diff --git a/conf/freeswitch.xml b/conf/freeswitch.xml index 32b474cb64..ce1570c5b6 100644 --- a/conf/freeswitch.xml +++ b/conf/freeswitch.xml @@ -22,6 +22,10 @@ + + + + @@ -77,7 +81,6 @@ - @@ -404,6 +407,19 @@ + + + + + + + + + + + + +
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See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with this library, in file named COPYING.LGPL; if not, +# write to the Free Software Foundation, Inc., 59 Temple Place, +# Suite 330, Boston, MA 02111-1307 USA + +VERS = 0.0.9pre +SRCS = udns_dn.c udns_dntosp.c udns_parse.c udns_resolver.c udns_misc.c \ + udns_rr_a.c udns_rr_ptr.c udns_rr_mx.c udns_rr_txt.c udns_bl.c \ + udns_rr_srv.c udns_rr_naptr.c udns_codes.c +USRCS = dnsget.c rblcheck.c ex-rdns.c +DEB = debian/copyright debian/changelog debian/control debian/rules +DIST = COPYING.LGPL udns.h udns.3 dnsget.1 rblcheck.1 $(SRCS) $(USRCS) \ + Makefile TODO NOTES + +OBJS = $(SRCS:.c=.o) $(GEN:.c=.o) +LIB = libudns.a + +SOVER = 0 +SOBJS = $(OBJS:.o=.lo) +SOLIB = libudns.so +SOLIBV = $(SOLIB).$(SOVER) + +LIBS = $(LIB) $(SOLIBV) + +UTILS = $(USRCS:.c=) +SOUTILS = $(USRCS:.c=.shared) + +NAMEPFX = udns-$(VERS) + +CC = gcc +CFLAGS = -Wall -W -Wmissing-prototypes -O2 -fPIC +CDEFS = -DHAVE_POLL +PICFLAGS = -fPIC +AWK = awk + +all: static + +.SUFFIXES: .c .o .lo .shared + +static: $(LIB) $(UTILS) +staticlib: $(LIB) +$(LIB): $(OBJS) + -rm -f $@ + $(AR) rv $@ $(OBJS) +.c.o: + $(CC) $(CFLAGS) $(CDEFS) -c $< +$(OBJS): udns.h + +$(UTILS): udns.h $(LIB) +.c: + $(CC) $(CFLAGS) $(CDEFS) -o $@ $< $(LIB) + +shared: $(SOLIBV) $(SOUTILS) +sharedlib: $(SOLIBV) + +$(SOLIBV): $(SOBJS) + $(CC) -shared -Wl,--soname,$(SOLIBV) -o $@ $(SOBJS) + rm -f $(SOLIB) + ln -s $(SOLIBV) $(SOLIB) +.c.lo: + $(CC) $(CFLAGS) $(PICFLAGS) $(CDEFS) -o $@ -c $< +$(SOBJS): udns.h + +$(SOUTILS): udns.h $(SOLIB) +.c.shared: + $(CC) $(CFLAGS) $(CDEFS) -o $@ $< $(SOLIB) + +# udns_codes.c is generated from udns.h +udns_codes.c: udns.h Makefile + @echo Generating $@ + @set -e; exec >$@.tmp; \ + set T type C class R rcode; \ + echo "/* Automatically generated. */"; \ + echo "#include \"udns.h\""; \ + while [ "$$1" ]; do \ + echo; \ + echo "const struct dns_nameval dns_$${2}tab[] = {"; \ + $(AWK) "/^ DNS_$${1}_[A-Z0-9_]+[ ]*=/ \ + { printf \" {%s,\\\"%s\\\"},\\n\", \$$1, substr(\$$1,7) }" \ + udns.h ; \ + echo " {0,0}};"; \ + echo "const char *dns_$${2}name(enum dns_$${2} code) {"; \ + echo " static char nm[20];"; \ + echo " switch(code) {"; \ + $(AWK) "BEGIN{i=0} \ + /^ DNS_$${1}_[A-Z0-9_]+[ ]*=/ \ + {printf \" case %s: return dns_$${2}tab[%d].name;\\n\",\$$1,i++}\ + " udns.h ; \ + echo " }"; \ + echo " return _dns_format_code(nm,\"$$2\",code);"; \ + echo "}"; \ + shift 2; \ + done + @mv $@.tmp $@ + +udns.3.html: udns.3 + groff -man -Thtml udns.3 > $@.tmp + mv $@.tmp $@ + +dist: $(NAMEPFX).tar.gz +$(NAMEPFX).tar.gz: $(DIST) $(DEB) + mkdir $(NAMEPFX) $(NAMEPFX)/debian + ln $(DIST) $(NAMEPFX) + ln $(DEB) $(NAMEPFX)/debian + tar cvfz $@ $(NAMEPFX) + rm -rf $(NAMEPFX) +subdist: + cp -p $(DIST) $(TARGET)/ + +clean: + rm -f $(OBJS) $(SOBJS) build-stamp +distclean: clean + rm -f $(LIBS) libudns.so udns.3.html $(UTILS) $(SOUTILS) + +.PHONY: all static staticlib shared sharedlib dist clean distclean subdist diff --git a/libs/udns/NOTES b/libs/udns/NOTES new file mode 100644 index 0000000000..3fe75c1f32 --- /dev/null +++ b/libs/udns/NOTES @@ -0,0 +1,193 @@ +Assorted notes about udns (library). + +UDP-only mode +~~~~~~~~~~~~~ + +First of all, since udns is (currently) UDP-only, there are some +shortcomings. + +It assumes that a reply will fit into a UDP buffer. With adoption of EDNS0, +and general robustness of IP stacks, in most cases it's not an issue. But +in some cases there may be problems: + + - if an RRset is "very large" so it does not fit even in buffer of size + requested by the library (current default is 4096; some servers limits + it further), we will not see the reply, or will only see "damaged" + reply (depending on the server) + + - many DNS servers ignores EDNS0 option requests. In this case, no matter + which buffer size udns library will request, such servers reply is limited + to 512 bytes (standard pre-EDNS0 DNS packet size). + + - some DNS servers, notable the ones used by Verisign for certain top-level + domains, chokes on EDNS0-enabled queries, returning FORMERR. Such + behavior isn't prohibited by DNS standards, but in my opinion it's at + least weird - the server can easily ignore EDNS0 options and send a + reply, instead of sending error. + Currently, udns does nothing in this situation, completely ignoring the + error returned by the server, and continue waiting for reply. It probably + should grok that this server does not understand EDNS0 and retry w/o the + options, but it does not. The end result - esp. if your local DNS + server or - worse - broken firewall which inspects DNS packets and drops + the ones which - from its point of view - are "broken" - is that you + see only TEMPFAIL errors from the library trying to resolve ANY names. + +Implementing TCP mode (together with non-EDNS0 fall-back as above) isn't +difficult, but it complicates API significantly. Currently udns uses only +single UDP socket (or - maybe in the future - two, see below), but in case of +TCP, it will need to open and close sockets for TCP connections left and +right, and that have to be integrated into an application's event loop in +an easy and efficient way. Plus all the timeouts - different for connect(), +write, and several stages of read. + +IPv6 vs IPv4 usage +~~~~~~~~~~~~~~~~~~ + +This is only relevant for nameservers reachable over IPv6, NOT for IPv6 +queries. I.e., if you've IPv6 addresses in 'nameservers' line in your +/etc/resolv.conf file. Even more: if you have BOTH IPv6 AND IPv4 addresses +there. Or pass them to udns initialization routines. + +Since udns uses a single UDP socket to communicate with all nameservers, +it should support both v4 and v6 communications. Most current platforms +supports this mode - using PF_INET6 socket and V4MAPPED addresses, i.e, +"tunnelling" IPv4 inside IPv6. But not all systems supports this. And +more, it has been said that such mode is deprecated. + +So, list only IPv4 or only IPv6 addresses, but don't mix them, in your +/etc/resolv.conf. + +An alternative is to use two sockets instead of 1 - one for IPv6 and one +for IPv4. For now I'm not sure if it's worth the complexity - again, of +the API, not the library itself (but this will not simplify library either). + +Single socket for all queries +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Using single UDP socket for sending queries to all nameservers has obvious +advantages. First it's, again, trivial, simple to use API. And simple +library too. Also, after sending queries to all nameservers (in case first +didn't reply in time), we will be able to receive late reply from first +nameserver and accept it. + +But this mode has disadvantages too. Most important is that it's much easier +to send fake reply to us, as the UDP port where we expects the reply to come +to is constant during the whole lifetime of an application. More secure +implementations uses random port for every single query. While port number +(16 bits integer) can not hold much randomness, it's still of some help. +Ok, udns is a stub resolver, so it expects sorta friendly environment, but +on LAN it's usually much easier to fire an attack, due to the speed of local +network, where a bad guy can generate alot of packets in a short time. + +Choosing of DNS QueryID +~~~~~~~~~~~~~~~~~~~~~~~ + +This is more a TODO item really. Currently, udns uses sequential number for +query IDs. Which simplifies attacks even more (c.f. the previous item about +single UDP port), making them nearly trivial. The library should use random +number for query ID. But there's no portable way to get random numbers, even +on various flavors of Unix. It's possible to use low bits from tv_nsec field +returned by gettimeofday() (current time, nanoseconds), but I wrote the library +in a way to avoid making system calls where possible, because many syscalls +means many context switches and slow processes as a result. Maybe use some +application-supplied callback to get random values will be a better way, +defaulting to gettimeofday() method. + +Note that a single query - even if (re)sent to different nameservers, several +times (due to no reply received in time), uses the same qID assigned when it +was first dispatched. So we have: single UDP socket (fixed port number), +sequential (= trivially predictable) qIDs, and long lifetime of those qIDs. +This all makes (local) attacks against the library really trivial. + +Assumptions about RRs returned +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Currently udns processes records in the reply it received sequentially. +This means that order of the records is significant. For example, if +we asked for foo.bar A, but the server returned that foo.bar is a CNAME +(alias) for bar.baz, and bar.baz, in turn, has address 1.2.3.4, when +the CNAME should come first in reply, followed by A. While DNS specs +does not say anything about order of records - it's an rrSET - unordered, - +I think an implementation which returns the records in "wrong" order is +somewhat insane... Well ok, to be fair, I don't really remember how +udns handles this now - need to check this in source... ;) + +CNAME recursion +~~~~~~~~~~~~~~~ + +Another dark point of udns is the handling of CNAMEs returned as replies +to non-CNAME queries. If we asked for foo.bar A, but it's a CNAME, udns +expects BOTH the CNAME itself and the target DN to be present in the reply. +In other words, udns DOES NOT RECURSE CNAMES. If we asked for foo.bar A, +but only record in reply was that foo.bar is a CNAME for bar.baz, udns will +return no records to an application (NXDOMAIN). Strictly speaking, udns +should repeat the query asking for bar.baz A, and recurse. But since it's +stub resolver, recursive resolver should recurse for us instead. + +It's not very difficult to implement, however. Probably with some (global?) +flag to en/dis-able the feature. Provided there's some demand for it. + +To clarify: udns handles CNAME recursion in a single reply packet just fine. + +Error reporting +~~~~~~~~~~~~~~~ + +Too many places in the code (various failure paths) sets generic "TEMPFAIL" +error condition. For example, if no nameserver replied to our query, an +application will get generic TEMPFAIL, instead of something like TIMEDOUT. +This probably should be fixed, but most applications don't care about the +exact reasons of failure - 4 common cases are already too much: + - query returned some valid data + - NXDOMAIN + - valid domain but no data of requested type - =NXDOMAIN in most cases + - temporary error - this one sometimes (incorrectly!) treated as NXDOMAIN + by (naive) applications. +DNS isn't yes/no, it's at least 3 variants, temp err being the 3rd important +case! And adding more variations for the temp error case is complicating things +even more - again, from an application writer standpoint. For diagnostics, +such more specific error cases are of good help. + +Planned API changes +~~~~~~~~~~~~~~~~~~~ + +At least one thing I want to change for 0.1 version is a way how queries are +submitted. + +I want to made dns_query object to be owned by an application. So that instead +of udns library allocating it for the lifetime of query, it will be pre- +allocated by an application. This simplifies and enhances query submitting +interface, and complicates it a bit too, in simplest cases. + +Currently, we have: + +dns_submit_dn(dn, cls, typ, flags, parse, cbck, data) +dns_submit_p(name, cls, typ, flags, parse, cbck, data) +dns_submit_a4(ctx, name, flags, cbck, data) + +and so on -- with many parameters missed for type-specific cases, but generic +cases being too complex for most common usage. + +Instead, with dns_query being owned by an app, we will be able to separately +set up various parts of the query - domain name (various forms), type&class, +parser, flags, callback... and even change them at runtime. And we will also +be able to reuse query structures, instead of allocating/freeing them every +time. So the whole thing will look something like: + + q = dns_alloc_query(); + dns_submit(dns_q_flags(dns_q_a4(q, name, cbck), DNS_F_NOSRCH), data); + +The idea is to have a set of functions accepting struct dns_query* and +returning it (so the calls can be "nested" like the above), to set up +relevant parts of the query - specific type of callback, conversion from +(type-specific) query parameters into a domain name (this is for type- +specific query initializers), and setting various flags and options and +type&class things. + +One example where this is almost essential - if we want to support +per-query set of nameservers (which isn't at all useless: imagine a +high-volume mail server, were we want to direct DNSBL queries to a separate +set of nameservers, and rDNS queries to their own set and so on). Adding +another argument (set of nameservers to use) to EVERY query submitting +routine is.. insane. Especially since in 99% cases it will be set to +default NULL. But with such "nesting" of query initializers, it becomes +trivial. diff --git a/libs/udns/TODO b/libs/udns/TODO new file mode 100644 index 0000000000..ce5bba1272 --- /dev/null +++ b/libs/udns/TODO @@ -0,0 +1,74 @@ +$Id: TODO,v 1.10 2005/04/19 21:48:09 mjt Exp $ + +The following is mostly an internal, not user-visible stuff. + +* rearrange an API to make dns_query object owned by application, + so that it'll look like this: + struct dns_query *q; + q = udns_query_alloc(ctx); + udns_query_set(q, options, domain_name, flags, ...); + udns_query_submit(ctx, q); + or + udns_query_resolve(ctx, q); + +* allow NULL callbacks? Or provide separate resolver + context list of queries which are done but wich did not + have callback, and dns_pick() routine to retrieve results + from this query, i.e. allow non-callback usage? The + non-callback usage may be handy sometimes (any *good* + example?), but it will be difficult to provide type-safe + non-callback interface due to various RR-specific types + in use. + +* DNS_OPT_FLAGS should be DNS_OPT_ADDFLAGS and DNS_OPT_SETFLAGS. + Currently one can't add a single flag bit but preserve + existing bits... at least not without retrieving all current + flags before, which isn't that bad anyway. + +* dns_set_opts() may process flags too (such as aaonly etc) + +* a way to disable $NSCACHEIP et al processing? + +* initialize/open the context automatically, and be more + liberal about initialization in general? + +* dns_init(do_open) - make the parameter opposite, aka + dns_init(skip_open) ? + +* for the above. Use separate routine for initializing the context + from system files, to not link stuff reading resolv.conf if it's + not needed. So that automatic init will not be possible. + +* allow TCP queue? + +* detect servers which don't understand EDNS0 (returning FORMERR), + and fall back to pre-EDNS0 for them. + +* for the above to work, we have to be able to find query object by + only ID, not ID + qdn. + +* And oh, qID should really be random. + +* more accurate error reporting. Currently, udns always returns TEMPFAIL, + but don't specify why it happened (ENOMEM, timeout, etc). + +* check the error value returned by recvfrom() and + sendto() and determine which errors to ignore. + +* maybe merge dns_timeouts() and dns_ioevent(), to have + only one entry point for everything? For traditional + select-loop-based eventloop it may be easier, but for + callback-driven event loops the two should be separate. + Provide an option, or a single dns_events() entry point + for select-loop approach, or just call dns_ioevent() + from within dns_timeouts() (probably after renaming + it to be dns_events()) ? + +* implement /etc/hosts lookup too, ala [c-]ares?? + +* sortlist support? + +* windows port? Oh no please!.. At least, I can't do it myself + because of the lack of platform. + Ok ok, the Windows port is in progress. Christian Prahauser + from cosy.sbg.ac.at is helping with that. diff --git a/libs/udns/debian/changelog b/libs/udns/debian/changelog new file mode 100644 index 0000000000..c393fea06a --- /dev/null +++ b/libs/udns/debian/changelog @@ -0,0 +1,94 @@ +udns (0.0.9pre) unstable; urgency=low + + * s/EOVERFLOW/ENFILE, partly to make win32 happy + + * several win32 fixes + + * don't use `class' in udns.h, to make C++ happy + (thanks Markus Koetter for pointing this out) + + * fixed CNAME handling in dnsget tool. Another Thank You! goes + to Markus Koetter. + + * NAPTR (RFC3403) support, thanks to Mikael Magnusson + for this. + + * more Win32 fixes from Mikael Magnusson. I have to admit + I never tried to compile it on Win32. + + * added NOTES file + + -- Michael Tokarev Wed, 29 Nov 2006 04:16:21 +0300 + +udns (0.0.8) unstable; urgency=low + + * don't compare sockaddr_in's, but individual parts only + (on some OSes, there are additional fields in this structure + so memcmp() does not quite work) + + * use dnsc_t instead of unsigned char for DNs everywhere + + * SRV records (rfc2782) parsing, thanks to + Thadeu Lima de Souza Cascardo. + + * manpage fixes + + -- Michael Tokarev Mon, 12 Sep 2005 16:06:45 +0400 + +udns (0.0.7) unstable; urgency=low + + * added dnsget.1 and rblcheck.1 manpages. + + * internal: use generic list implementation in udns_resolver.c + + * don't assume only backward DN pointers in replies, allow forward + pointers too. This is quite large change, involves changing + parsing API all over the places. + + * internal: typedef dnsc_t and dnscc_t for [const] unsigned char, to + make function prototypes shorter to better fit on a single line. + + * in parsing routines, verify (assert) that the query type + is the one we can handle. + + * recognize names (and resolve them) as nameservers in dnsget. + + * when new request is submitted, don't send it immediately, but + add it into the head of the active queue with deadline=0. + This will allow us to tweak some query settings before it will + be processed. + Note API change: removed `now' argument from all dns_submit_*() + routines. + + * use single per-context user timer, not per-query. + Note API change: different user timer callback + + * add dnsc_salen field -- length of the socket address used + + * fix dns_set_opt(DNS_OPT_FLAGS) which didn't work before + + * allow to set some options for a context wich is open but with no + active queries + + -- Michael Tokarev Thu, 5 May 2005 23:14:29 +0400 + +udns (0.0.6) unstable; urgency=low + + * 0.0.6 release. + ALOT of changes all over. Keep 'em in CVS logs! + + -- Michael Tokarev Fri, 8 Apr 2005 19:51:38 +0400 + +udns (0.0.5) unstable; urgency=low + + * Initial Release. + * Provides 3 packages: + libudns0 - shared library + libudns-dev - development files and static library + udns-utils - dnsget, rblcheck + + -- Michael Tokarev Thu, 7 Apr 2005 00:05:24 +0400 + +Local variables: +mode: debian-changelog +End: diff --git a/libs/udns/debian/control b/libs/udns/debian/control new file mode 100644 index 0000000000..f7234f54ac --- /dev/null +++ b/libs/udns/debian/control @@ -0,0 +1,33 @@ +Source: udns +Priority: optional +Maintainer: Michael Tokarev +Build-Depends: debhelper (>= 4.0.0) +Standards-Version: 3.6.1 + +Package: libudns0 +Section: lib +Architecture: any +Depends: ${shlibs:Depends} +Description: async-capable DNS stub resolver library + libudns0 package provides libudns shared library needed + to run programs using it + +Package: libudns-dev +Section: libdev +Architecture: any +Depends: libudns0 (= ${Source-Version}) +Description: async-capable DNS stub resolver library, development files + This package provides development files needed + to build programs using udns library + +Package: udns-utils +Section: net +Architecture: any +Depends: ${shlibs:Depends} +Conflicts: rblcheck +Description: Several DNS-related utilities built on top of udns library + This package includes the following utilities: + dnsget - a simple DNS query tool, like `host' or `dig' for usage from + a command line, and dnsip, dnsname etc for usage in scripts + rblcheck - DNSBL (rbl) checker + All the utilities are built using udns library diff --git a/libs/udns/debian/copyright b/libs/udns/debian/copyright new file mode 100644 index 0000000000..089491bc69 --- /dev/null +++ b/libs/udns/debian/copyright @@ -0,0 +1,24 @@ +This is udns, written and maintained by Michael Tokarev + +The original source can always be found at: + http://www.corpit.ru/mjt/udns.html + +Copyright (C) 2005 Michael Tokarev + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this package; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA + 02111-1307, USA. + +On Debian systems, the complete text of the GNU General +Public License can be found in `/usr/share/common-licenses/GPL'. diff --git a/libs/udns/debian/rules b/libs/udns/debian/rules new file mode 100755 index 0000000000..07dc8b874f --- /dev/null +++ b/libs/udns/debian/rules @@ -0,0 +1,91 @@ +#!/usr/bin/make -f +# -*- makefile -*- +# This file was originally written by Joey Hess and Craig Small. +# As a special exception, when this file is copied by dh-make into a +# dh-make output file, you may use that output file without restriction. +# This special exception was added by Craig Small in version 0.37 of dh-make. + +# Uncomment this to turn on verbose mode. +#export DH_VERBOSE=1 +export DH_COMPAT=4 + +CFLAGS = -Wall -W -Wmissing-prototypes -g +CDEFS = -DHAVE_POOL + +INSTALL = install +INSTALL_PROGRAM = $(INSTALL) -p +INSTALL_DATA = $(INSTALL) -p -m0644 + +ifneq (,$(findstring noopt,$(DEB_BUILD_OPTIONS))) + CFLAGS += -O0 +else + CFLAGS += -O2 +endif +ifeq (,$(findstring nostrip,$(DEB_BUILD_OPTIONS))) + INSTALL_PROGRAM += -s +endif +ifeq (,$(findstring debug,$(DEB_BUILD_OPTIONS))) +# CDEFS += -DNDEBUG +endif + +SOVER = 0 + +configure: # nothing + dh_testdir + +build: build-stamp +build-stamp: + dh_testdir + $(MAKE) CFLAGS="$(CFLAGS)" CDEFS="$(CDEFS)" SOVER=$(SOVER) \ + staticlib sharedlib rblcheck.shared dnsget.shared + mv -f rblcheck.shared rblcheck + mv -f dnsget.shared dnsget + touch $@ + +clean: + dh_testdir + rm -f build-stamp + $(MAKE) distclean + dh_clean + +install: build + dh_testdir + dh_testroot + dh_clean + dh_installdirs + dh_installdocs -A NEWS + +# libudns + dh_install -plibudns$(SOVER) libudns.so.$(SOVER) usr/lib + +# libudns-dev + dh_install -plibudns-dev libudns.a libudns.so usr/lib + dh_install -plibudns-dev udns.h usr/include + dh_installman -plibudns-dev udns.3 + dh_installdocs -plibudns-dev TODO NOTES + dh_installexamples -plibudns-dev ex-rdns.c + +# udns-utils + dh_installdirs -pudns-utils usr/bin + dh_install -pudns-utils dnsget rblcheck usr/bin + dh_installman -pudns-utils dnsget.1 rblcheck.1 + +binary-indep: build install + +binary-arch: build install + dh_testdir + dh_testroot + dh_installchangelogs + dh_installdocs + dh_strip + dh_compress + dh_fixperms + dh_makeshlibs + dh_installdeb + dh_shlibdeps -L libudns$(SOVER) -l debian/libudns$(SOVER)/usr/lib + dh_gencontrol + dh_md5sums + dh_builddeb + +binary: binary-indep binary-arch +.PHONY: build clean binary-indep binary-arch binary install configure diff --git a/libs/udns/dnsget.1 b/libs/udns/dnsget.1 new file mode 100644 index 0000000000..711f29769e --- /dev/null +++ b/libs/udns/dnsget.1 @@ -0,0 +1,182 @@ +.\" $Id: dnsget.1,v 1.3 2005/04/20 00:55:34 mjt Exp $ +.\" dnsget manpage +.\" +.\" Copyright (C) 2005 Michael Tokarev +.\" This file is part of UDNS library, an async DNS stub resolver. +.\" +.\" This library is free software; you can redistribute it and/or +.\" modify it under the terms of the GNU Lesser General Public +.\" License as published by the Free Software Foundation; either +.\" version 2.1 of the License, or (at your option) any later version. +.\" +.\" This library is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +.\" Lesser General Public License for more details. +.\" +.\" You should have received a copy of the GNU Lesser General Public +.\" License along with this library, in file named COPYING.LGPL; if not, +.\" write to the Free Software Foundation, Inc., 59 Temple Place, +.\" Suite 330, Boston, MA 02111-1307 USA + +.TH dnsget 1 "Apr 2005" "User Utilities" + +.SH NAME +dnsget \- DNS lookup utility + +.SH SYNOPSYS +.B dnsget +.RB [\| \-v \||\| \-q \|] +.RB [\| \-c +.IR class \|] +.RB [\| \-t +.IR type \|] +.RB [\| \-o +.IR option : value \] +.IR name \|.\|.\|. + +.SH DESCRIPTION +.B dnsget +is a simple command-line to perform DNS lookups, similar to +.BR host (1) +and +.BR dig (1). +It is useable for both interactive/debugging scenarious and +in scripts. +The program is implemented using +.BR udns (3) +library. + +.PP +By default, +.B dnsget +produces a human-readable output, similar to +.RS +.nf +alias.example.com. CNAME www.example.com. +www.example.com. A 192.168.1.1 +www.example.com. MX 10 mx.example.com. +.fi +.RE +which is just sufficient to see how a given name resolves. +Output format is controllable with +.B \-v +and +.B \-q +options -- the former increases verbosity level up to printing +the whole DNS contents of all packets sent and received, which +is suitable for debugging DNS problems, while the latter reduces +the level, making output more quiet, up to bare result with no +error messages, which is good for scripts. + +.SH OPTIONS + +The following options are recognized by +.BR dnsget : + +.TP +.B \-v +produce more detailed output. More +.BR \-v 's +means more details will be produced. With single +.BR \-v , dnsget +will print contents of all received DNS packets (in a readable format), +while with +.BR \-vv , +it will output all outgoing DNS packets too. + +.TP +.B \-q +the opposite for \fB\-v\fR -- produce less detailed output. +With single +.BR \-q , dnsget +will only show (decoded) data from final DNS resource records (RR), +while +.B \-qq +also suppresses error messages. + +.TP +\fB\-t \fItype\fR +request record(s) of the given type \fItype\fR. By default, +.B dnsget +will ask for IPv4 address (A) record, or for PTR record if the +argument in question is an IPv4 or IPv6 address. Recognized +types include A, AAAA, MX, TXT, CNAME, PTR, NS, SOA, ANY and +others. + +.TP +\fB\-c \fIclass\fR +request DNS record(s) of the given class \fIclass\fR. By +default +.B dnsget +uses IN class. Valid classes include IN, CH, HS, ANY. + +.TP +.B \-a +(compatibility option). Equivalent to setting query type to +.B ANY +and increasing verbosity level +.RB ( \-v ). + +.TP +.B \-C +(planned) + +.TP +.B \-x +(planned) + +.TP +\fB\-o \fIoption\fR:\fIvalue\fR +Set resolver option \fIoption\fR to the value \fIvalue\fR +(may be specified several times). The same as setting +.RB $ RES_OPTIONS +environment variable. The following options are recognized: +.RS +.TP +\fBtimeout\fR:\fIsec\fR +Set initial query timeout to \fIsec\fR. +.TP +\fBattempts\fR:\fInum\fR +(re)try every query \fInum\fR times before failing. +.TP +\fBudpbuf\fR:\fIbytes\fR +set DNS UDP buffer size to \fIbytes\fR bytes. Valid values +are from 512 to 65535. If \fIbytes\fR is greather than 512, +EDNS0 (RFC 2671) extensions will be used. +.TP +\fBport\fR:\fInum\fR +Use given UDP port number \fInum\fR instead of the default port 53 (domain). +.RE + +.TP +\fB\-n \fInameserver\fR +Use the given nameserver(s) (may be specified more than once) +instead of the default. Using this option has the same same effect as +.RB $ NSCACHEIP +or +.RB $ NAMESERVERS +environment variables, with the only difference that only IPv4 addresses +are recognized for now, and it is possible to specify names (which will +be resolved using default settings) instead of IP addresses. + +.TP +.B \-h +print short help and exit. + +.SH "RETURN VALUE" +When all names where resovled successefully, +.B dnsget +exits with zero exit status. If at least one name was not found, +.B dnsget +will exit with return code 100. If some other error occured during +name resolution, it will exit with code 99. In case of usage or +initialization error, +.B dnsget +will return 1. + +.SH "SEE ALSO" +.BR host (1) +.BR dig (1) +.BR resolv.conf (5) +.BR udns (3). diff --git a/libs/udns/dnsget.c b/libs/udns/dnsget.c new file mode 100644 index 0000000000..1d89a52808 --- /dev/null +++ b/libs/udns/dnsget.c @@ -0,0 +1,709 @@ +/* $Id: dnsget.c,v 1.22 2006/11/29 21:28:49 mjt Exp $ + simple host/dig-like application using UDNS library + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "udns.h" + +static char *progname; +static int verbose = 1; +static int errors; +static int notfound; + +/* verbosity level: + * <0 - bare result + * 0 - bare result and error messages + * 1 - readable result + * 2 - received packet contents and `trying ...' stuff + * 3 - sent and received packet contents + */ + +static void die(int errnum, const char *fmt, ...) { + va_list ap; + fprintf(stderr, "%s: ", progname); + va_start(ap, fmt); vfprintf(stderr, fmt, ap); va_end(ap); + if (errnum) fprintf(stderr, ": %s\n", strerror(errnum)); + else putc('\n', stderr); + fflush(stderr); + exit(1); +} + +struct query { + const char *name; /* original query string */ + unsigned char *dn; /* the DN being looked up */ + enum dns_type qtyp; /* type of the query */ +}; + +static void query_free(struct query *q) { + free(q->dn); + free(q); +} + +static struct query * +query_new(const char *name, const unsigned char *dn, enum dns_type qtyp) { + struct query *q = malloc(sizeof(*q)); + unsigned l = dns_dnlen(dn); + unsigned char *cdn = malloc(l); + if (!q || !cdn) die(0, "out of memory"); + memcpy(cdn, dn, l); + q->name = name; + q->dn = cdn; + q->qtyp = qtyp; + return q; +} + +static enum dns_class qcls = DNS_C_IN; + +static void +dnserror(struct query *q, int errnum) { + if (verbose >= 0) + fprintf(stderr, "%s: unable to lookup %s record for %s: %s\n", progname, + dns_typename(q->qtyp), dns_dntosp(q->dn), dns_strerror(errnum)); + if (errnum == DNS_E_NXDOMAIN || errnum == DNS_E_NODATA) + ++notfound; + else + ++errors; + query_free(q); +} + +static const unsigned char * +printtxt(const unsigned char *c) { + unsigned n = *c++; + const unsigned char *e = c + n; + if (verbose > 0) while(c < e) { + if (*c < ' ' || *c >= 127) printf("\\%02x", *c); + else if (*c == '\\' || *c == '"') printf("\\%c", *c); + else putchar(*c); + ++c; + } + else + fwrite(c, n, 1, stdout); + return e; +} + +static void +printhex(const unsigned char *c, const unsigned char *e) { + while(c < e) + printf("%02x", *c++); +} + +static unsigned char to_b64[] = +"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +static void +printb64(const unsigned char *c, const unsigned char *e) { + while(c < e) { + putchar(to_b64[c[0] >> 2]); + if (c+1 < e) { + putchar(to_b64[(c[0] & 0x3) << 4 | c[1] >> 4]); + if (c+2 < e) { + putchar(to_b64[(c[1] & 0xf) << 2 | c[2] >> 6]); + putchar(to_b64[c[2] & 0x3f]); + } + else { + putchar(to_b64[(c[1] & 0xf) << 2]); + putchar('='); + break; + } + } + else { + putchar(to_b64[(c[0] & 0x3) << 4]); + putchar('='); + putchar('='); + break; + } + c += 3; + } +} + +static void +printdate(time_t time) { + struct tm *tm = gmtime(&time); + printf("%04d%02d%02d%02d%02d%02d", + tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, + tm->tm_hour, tm->tm_min, tm->tm_sec); +} + +static void +printrr(const struct dns_parse *p, struct dns_rr *rr) { + const unsigned char *pkt = p->dnsp_pkt; + const unsigned char *end = p->dnsp_end; + const unsigned char *dptr = rr->dnsrr_dptr; + const unsigned char *dend = rr->dnsrr_dend; + unsigned char *dn = rr->dnsrr_dn; + const unsigned char *c; + unsigned n; + + if (verbose > 0) { + if (verbose > 1) { + if (!p->dnsp_rrl && !rr->dnsrr_dn[0] && rr->dnsrr_typ == DNS_T_OPT) { + printf(";EDNS0 OPT record (UDPsize: %d): %d bytes\n", + rr->dnsrr_cls, rr->dnsrr_dsz); + return; + } + n = printf("%s.", dns_dntosp(rr->dnsrr_dn)); + printf("%s%u\t%s\t%s\t", + n > 15 ? "\t" : n > 7 ? "\t\t" : "\t\t\t", + rr->dnsrr_ttl, + dns_classname(rr->dnsrr_cls), + dns_typename(rr->dnsrr_typ)); + } + else + printf("%s. %s ", dns_dntosp(rr->dnsrr_dn), dns_typename(rr->dnsrr_typ)); + } + + switch(rr->dnsrr_typ) { + + case DNS_T_CNAME: + case DNS_T_PTR: + case DNS_T_NS: + case DNS_T_MB: + case DNS_T_MD: + case DNS_T_MF: + case DNS_T_MG: + case DNS_T_MR: + if (dns_getdn(pkt, &dptr, end, dn, DNS_MAXDN) <= 0) goto xperr; + printf("%s.", dns_dntosp(dn)); + break; + + case DNS_T_A: + if (rr->dnsrr_dsz != 4) goto xperr; + printf("%d.%d.%d.%d", dptr[0], dptr[1], dptr[2], dptr[3]); + break; + + case DNS_T_AAAA: + if (rr->dnsrr_dsz != 16) goto xperr; + printf("%s", inet_ntop(AF_INET6, dptr, (char*)dn, DNS_MAXDN)); + break; + + case DNS_T_MX: + c = dptr + 2; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || c != dend) goto xperr; + printf("%d %s.", dns_get16(dptr), dns_dntosp(dn)); + break; + + case DNS_T_TXT: + /* first verify it */ + for(c = dptr; c < dend; c += n) { + n = *c++; + if (c + n > dend) goto xperr; + } + c = dptr; n = 0; + while (c < dend) { + if (verbose > 0) printf(n++ ? "\" \"":"\""); + c = printtxt(c); + } + if (verbose > 0) putchar('"'); + break; + + case DNS_T_HINFO: /* CPU, OS */ + c = dptr; + n = *c++; if ((c += n) >= dend) goto xperr; + n = *c++; if ((c += n) != dend) goto xperr; + c = dptr; + if (verbose > 0) putchar('"'); + c = printtxt(c); + if (verbose > 0) printf("\" \""); else putchar(' '); + printtxt(c); + if (verbose > 0) putchar('"'); + break; + + case DNS_T_WKS: + c = dptr; + if (dptr + 4 + 2 >= end) goto xperr; + printf("%s %d", inet_ntoa(*((struct in_addr*)dptr)), dptr[4]); + c = dptr + 5; + for (n = 0; c < dend; ++c, n += 8) { + if (*c) { + unsigned b; + for (b = 0; b < 8; ++b) + if (*c & (1 << (7-b))) printf(" %d", n + b); + } + } + break; + + case DNS_T_SRV: /* prio weight port targetDN */ + c = dptr; + c += 2 + 2 + 2; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || c != dend) goto xperr; + c = dptr; + printf("%d %d %d %s.", + dns_get16(c+0), dns_get16(c+2), dns_get16(c+4), + dns_dntosp(dn)); + break; + + case DNS_T_NAPTR: /* order pref flags serv regexp repl */ + c = dptr; + c += 4; /* order, pref */ + for (n = 0; n < 3; ++n) + if (c >= dend) goto xperr; + else c += *c + 1; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || c != dend) goto xperr; + c = dptr; + printf("%u %u", dns_get16(c+0), dns_get16(c+2)); + c += 4; + for(n = 0; n < 3; ++n) { + putchar(' '); + if (verbose > 0) putchar('"'); + c = printtxt(c); + if (verbose > 0) putchar('"'); + } + printf(" %s.", dns_dntosp(dn)); + break; + + case DNS_T_KEY: /* flags(2) proto(1) algo(1) pubkey */ + c = dptr; + if (c + 2 + 1 + 1 > dend) goto xperr; + printf("%d %d %d", dns_get16(c), c[2], c[3]); + c += 2 + 1 + 1; + if (c < dend) { + putchar(' '); + printb64(c, dend); + } + break; + + case DNS_T_SIG: + /* type(2) algo(1) labels(1) ottl(4) sexp(4) sinc(4) tag(2) sdn sig */ + c = dptr; + c += 2 + 1 + 1 + 4 + 4 + 4 + 2; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0) goto xperr; + printf("%d %u %u %u ", + dns_get16(dptr), dptr[2], dptr[3], dns_get32(dptr+4)); + printdate(dns_get32(dptr+8)); + putchar(' '); + printdate(dns_get32(dptr+12)); + printf(" %d %s. ", dns_get16(dptr+10), dns_dntosp(dn)); + printb64(c, dend); + break; + +#if 0 /* unused RR types? */ + case DNS_T_DS: + c = dptr; + if (c + 2 + 2 >= dend) goto xperr; + printf("%u %u %u ", dns_get16(c), c[2], c[3]); + printhex(c + 4, dend); + break; + + case DNS_T_NSEC: + c = dptr; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0) goto xperr; + printf("%s.", dns_dntosp(dn)); + unfinished. + break; +#endif + + + case DNS_T_SOA: + c = dptr; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || + dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || + c + 4*5 != dend) + goto xperr; + dns_getdn(pkt, &dptr, end, dn, DNS_MAXDN); + printf("%s. ", dns_dntosp(dn)); + dns_getdn(pkt, &dptr, end, dn, DNS_MAXDN); + printf("%s. ", dns_dntosp(dn)); + printf("%u %u %u %u %u", + dns_get32(dptr), dns_get32(dptr+4), dns_get32(dptr+8), + dns_get32(dptr+12), dns_get32(dptr+16)); + break; + + case DNS_T_MINFO: + c = dptr; + if (dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || + dns_getdn(pkt, &c, end, dn, DNS_MAXDN) <= 0 || + c != dend) + goto xperr; + dns_getdn(pkt, &dptr, end, dn, DNS_MAXDN); + printf("%s. ", dns_dntosp(dn)); + dns_getdn(pkt, &dptr, end, dn, DNS_MAXDN); + printf("%s.", dns_dntosp(dn)); + break; + + case DNS_T_NULL: + default: + printhex(dptr, dend); + break; + } + putchar('\n'); + return; + +xperr: + printf("\n"); + ++errors; +} + +static int +printsection(struct dns_parse *p, int nrr, const char *sname) { + struct dns_rr rr; + int r; + if (!nrr) return 0; + if (verbose > 1) printf("\n;; %s section (%d):\n", sname, nrr); + + p->dnsp_rrl = nrr; + while((r = dns_nextrr(p, &rr)) > 0) + printrr(p, &rr); + if (r < 0) printf("<>\n"); + return r; +} + +/* dbgcb will only be called if verbose > 1 */ +static void +dbgcb(int code, const struct sockaddr *sa, unsigned slen, + const unsigned char *pkt, int r, + const struct dns_query *unused_q, void *unused_data) { + struct dns_parse p; + const unsigned char *cur, *end; + int numqd; + + if (code > 0) { + printf(";; trying %s.\n", dns_dntosp(dns_payload(pkt))); + printf(";; sending %d bytes query to ", r); + } + else + printf(";; received %d bytes response from ", r); + if (sa->sa_family == AF_INET && slen >= sizeof(struct sockaddr_in)) { + char buf[4*4]; + printf("%s port %d\n", + inet_ntop(AF_INET, &((struct sockaddr_in*)sa)->sin_addr, + buf, sizeof(buf)), + htons(((struct sockaddr_in*)sa)->sin_port)); + } +#ifdef AF_INET6 + else if (sa->sa_family == AF_INET6 && slen >= sizeof(struct sockaddr_in6)) { + char buf[6*5+4*4]; + printf("%s port %d\n", + inet_ntop(AF_INET6, &((struct sockaddr_in6*)sa)->sin6_addr, + buf, sizeof(buf)), + htons(((struct sockaddr_in6*)sa)->sin6_port)); + } +#endif + else + printf("<>\n", sa->sa_family); + if (code > 0 && verbose < 3) { + putchar('\n'); + return; + } + + if (code == -2) printf(";; reply from unexpected source\n"); + if (code == -5) printf(";; reply to a query we didn't sent (or old)\n"); + if (r < DNS_HSIZE) { + printf(";; short packet (%d bytes)\n", r); + return; + } + if (dns_opcode(pkt) != 0) + printf(";; unexpected opcode %d\n", dns_opcode(pkt)); + if (dns_tc(pkt) != 0) + printf(";; warning: TC bit set, probably incomplete reply\n"); + + printf(";; ->>HEADER<<- opcode: "); + switch(dns_opcode(pkt)) { + case 0: printf("QUERY"); break; + case 1: printf("IQUERY"); break; + case 2: printf("STATUS"); break; + default: printf("UNKNOWN(%u)", dns_opcode(pkt)); break; + } + printf(", status: %s, id: %d, size: %d\n;; flags:", + dns_rcodename(dns_rcode(pkt)), dns_qid(pkt), r); + if (dns_qr(pkt)) printf(" qr"); + if (dns_rd(pkt)) printf(" rd"); + if (dns_ra(pkt)) printf(" ra"); + if (dns_aa(pkt)) printf(" aa"); + if (dns_tc(pkt)) printf(" tc"); + numqd = dns_numqd(pkt); + printf("; QUERY: %d, ANSWER: %d, AUTHORITY: %d, ADDITIONAL: %d\n", + numqd, dns_numan(pkt), dns_numns(pkt), dns_numar(pkt)); + if (numqd != 1) + printf(";; unexpected number of entries in QUERY section: %d\n", + numqd); + printf("\n;; QUERY SECTION (%d):\n", numqd); + cur = dns_payload(pkt); + end = pkt + r; + while(numqd--) { + if (dns_getdn(pkt, &cur, end, p.dnsp_dnbuf, DNS_MAXDN) <= 0 || + cur + 4 > end) { + printf("; invalid query section\n"); + return; + } + r = printf(";%s.", dns_dntosp(p.dnsp_dnbuf)); + printf("%s%s\t%s\n", + r > 23 ? "\t" : r > 15 ? "\t\t" : r > 7 ? "\t\t\t" : "\t\t\t\t", + dns_classname(dns_get16(cur+2)), dns_typename(dns_get16(cur))); + cur += 4; + } + + p.dnsp_pkt = pkt; + p.dnsp_cur = p.dnsp_ans = cur; + p.dnsp_end = end; + p.dnsp_qdn = NULL; + p.dnsp_qcls = p.dnsp_qtyp = 0; + p.dnsp_ttl = 0xffffffffu; + p.dnsp_nrr = 0; + + r = printsection(&p, dns_numan(pkt), "ANSWER"); + if (r == 0) + r = printsection(&p, dns_numns(pkt), "AUTHORITY"); + if (r == 0) + r = printsection(&p, dns_numar(pkt), "ADDITIONAL"); + putchar('\n'); +} + +static void dnscb(struct dns_ctx *ctx, void *result, void *data) { + int r = dns_status(ctx); + struct query *q = data; + struct dns_parse p; + struct dns_rr rr; + unsigned nrr; + unsigned char dn[DNS_MAXDN]; + const unsigned char *pkt, *cur, *end; + if (!result) { + dnserror(q, r); + return; + } + pkt = result; end = pkt + r; cur = dns_payload(pkt); + dns_getdn(pkt, &cur, end, dn, sizeof(dn)); + dns_initparse(&p, NULL, pkt, cur, end); + p.dnsp_qcls = p.dnsp_qtyp = 0; + nrr = 0; + while((r = dns_nextrr(&p, &rr)) > 0) { + if (!dns_dnequal(dn, rr.dnsrr_dn)) continue; + if ((qcls == DNS_C_ANY || qcls == rr.dnsrr_cls) && + (q->qtyp == DNS_T_ANY || q->qtyp == rr.dnsrr_typ)) + ++nrr; + else if (rr.dnsrr_typ == DNS_T_CNAME && !nrr) { + if (dns_getdn(pkt, &rr.dnsrr_dptr, end, + p.dnsp_dnbuf, sizeof(p.dnsp_dnbuf)) <= 0 || + rr.dnsrr_dptr != rr.dnsrr_dend) { + r = DNS_E_PROTOCOL; + break; + } + else { + if (verbose == 1) { + printf("%s.", dns_dntosp(dn)); + printf(" CNAME %s.\n", dns_dntosp(p.dnsp_dnbuf)); + } + dns_dntodn(p.dnsp_dnbuf, dn, sizeof(dn)); + } + } + } + if (!r && !nrr) + r = DNS_E_NODATA; + if (r < 0) { + dnserror(q, r); + free(result); + return; + } + if (verbose < 2) { /* else it is already printed by dbgfn */ + dns_rewind(&p, NULL); + p.dnsp_qtyp = q->qtyp; + p.dnsp_qcls = qcls; + while(dns_nextrr(&p, &rr)) + printrr(&p, &rr); + } + free(result); + query_free(q); +} + +int main(int argc, char **argv) { + int i; + int fd; + fd_set fds; + struct timeval tv; + time_t now; + char *ns[DNS_MAXSERV]; + int nns = 0; + struct query *q; + enum dns_type qtyp = 0; + struct dns_ctx *nctx = NULL; + + if (!(progname = strrchr(argv[0], '/'))) progname = argv[0]; + else argv[0] = ++progname; + + if (argc <= 1) + die(0, "try `%s -h' for help", progname); + + if (dns_init(0) < 0 || !(nctx = dns_new(NULL))) + die(errno, "unable to initialize dns library"); + /* we keep two dns contexts: one may be needed to resolve + * nameservers if given as names, using default options. + */ + + while((i = getopt(argc, argv, "vqt:c:an:o:h")) != EOF) switch(i) { + case 'v': ++verbose; break; + case 'q': --verbose; break; + case 't': + if (optarg[0] == '*' && !optarg[1]) + i = DNS_T_ANY; + else if ((i = dns_findtypename(optarg)) <= 0) + die(0, "unrecognized query type `%s'", optarg); + qtyp = i; + break; + case 'c': + if (optarg[0] == '*' && !optarg[1]) + i = DNS_C_ANY; + else if ((i = dns_findclassname(optarg)) < 0) + die(0, "unrecognized query class `%s'", optarg); + qcls = i; + break; + case 'a': + qtyp = DNS_T_ANY; + ++verbose; + break; + case 'n': + if (nns >= DNS_MAXSERV) + die(0, "too many nameservers, %d max", DNS_MAXSERV); + ns[nns++] = optarg; + break; + case 'o': + if (dns_set_opts(NULL, optarg) != 0) + die(0, "invalid option string: `%s'", optarg); + break; + case 'h': + printf( +"%s: simple DNS query tool (using udns version %s)\n" +"Usage: %s [options] domain-name...\n" +"where options are:\n" +" -h - print this help and exit\n" +" -v - be more verbose\n" +" -q - be less verbose\n" +" -t type - set query type (A, AA, PTR etc)\n" +" -c class - set query class (IN (default), CH, HS, *)\n" +" -a - equivalent to -t ANY -v\n" +" -n ns - use given nameserver(s) instead of default\n" +" (may be specified multiple times)\n" +" -o option:value - set resovler option (the same as setting $RES_OPTIONS):\n" +" timeout:sec - initial query timeout\n" +" attempts:num - number of attempt to resovle a query\n" +" ndots:num - if name has more than num dots, lookup it before search\n" +" port:num - port number for queries instead of default 53\n" +" udpbuf:num - size of UDP buffer (use EDNS0 if >512)\n" +" (may be specified more than once)\n" + , progname, dns_version(), progname); + return 0; + default: + die(0, "try `%s -h' for help", progname); + } + + argc -= optind; argv += optind; + if (!argc) + die(0, "no name(s) to query specified"); + + if (nns) { + /* if nameservers given as names, resolve them. + * We only allow IPv4 nameservers as names for now. + * Ok, it is easy enouth to try both AAAA and A, + * but the question is what to do by default. + */ + struct sockaddr_in sin; + int j, r = 0, opened = 0; + memset(&sin, 0, sizeof(sin)); + sin.sin_family = AF_INET; + sin.sin_port = htons(dns_set_opt(NULL, DNS_OPT_PORT, -1)); + dns_add_serv(NULL, NULL); + for(i = 0; i < nns; ++i) { + if (!inet_aton(ns[i], &sin.sin_addr)) { + struct dns_rr_a4 *rr; + if (!opened) { + if (dns_open(nctx) < 0) + die(errno, "unable to initialize dns context"); + opened = 1; + } + rr = dns_resolve_a4(nctx, ns[i], 0); + if (!rr) + die(0, "unable to resolve nameserver %s: %s", + ns[i], dns_strerror(dns_status(nctx))); + for(j = 0; j < rr->dnsa4_nrr; ++j) { + sin.sin_addr = rr->dnsa4_addr[j]; + if ((r = dns_add_serv_s(NULL, (struct sockaddr *)&sin)) < 0) + break; + } + free(rr); + } + else + r = dns_add_serv_s(NULL, (struct sockaddr *)&sin); + if (r < 0) + die(errno, "unable to add nameserver %s", inet_ntoa(sin.sin_addr)); + } + } + dns_free(nctx); + + fd = dns_open(NULL); + if (fd < 0) + die(errno, "unable to initialize dns context"); + + if (verbose > 1) + dns_set_dbgfn(NULL, dbgcb); + + for (i = 0; i < argc; ++i) { + char *name = argv[i]; + union { + struct in_addr addr; + struct in6_addr addr6; + } a; + unsigned char dn[DNS_MAXDN]; + enum dns_type l_qtyp = 0; + int abs; + if (inet_pton(AF_INET, name, &a.addr) > 0) { + dns_a4todn(&a.addr, 0, dn, sizeof(dn)); + l_qtyp = DNS_T_PTR; + abs = 1; + } + else if (inet_pton(AF_INET6, name, &a.addr6) > 0) { + dns_a6todn(&a.addr6, 0, dn, sizeof(dn)); + l_qtyp = DNS_T_PTR; + abs = 1; + } + else if (!dns_ptodn(name, strlen(name), dn, sizeof(dn), &abs)) + die(0, "invalid name `%s'\n", name); + else + l_qtyp = DNS_T_A; + if (qtyp) l_qtyp = qtyp; + q = query_new(name, dn, l_qtyp); + if (abs) abs = DNS_NOSRCH; + if (!dns_submit_dn(NULL, dn, qcls, l_qtyp, abs, 0, dnscb, q)) + dnserror(q, dns_status(NULL)); + } + + FD_ZERO(&fds); + now = 0; + while((i = dns_timeouts(NULL, -1, now)) > 0) { + FD_SET(fd, &fds); + tv.tv_sec = i; + tv.tv_usec = 0; + i = select(fd+1, &fds, 0, 0, &tv); + now = time(NULL); + if (i > 0) dns_ioevent(NULL, now); + } + + return errors ? 1 : notfound ? 100 : 0; +} diff --git a/libs/udns/ex-rdns.c b/libs/udns/ex-rdns.c new file mode 100644 index 0000000000..bc705c74d7 --- /dev/null +++ b/libs/udns/ex-rdns.c @@ -0,0 +1,111 @@ +/* $Id: ex-rdns.c,v 1.6 2005/05/07 12:21:42 mjt Exp $ + parallel rDNS resolver example - read IP addresses from stdin, + write domain names to stdout + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "udns.h" + +static int curq; + +static const char *n2ip(const unsigned char *c) { + static char b[sizeof("255.255.255.255")]; + sprintf(b, "%u.%u.%u.%u", c[0], c[1], c[2], c[3]); + return b; +} +static void dnscb(struct dns_ctx *ctx, struct dns_rr_ptr *rr, void *data) { + const char *ip = n2ip((unsigned char *)&data); + int i; + --curq; + if (rr) { + printf("%s", ip); + for(i = 0; i < rr->dnsptr_nrr; ++i) + printf(" %s", rr->dnsptr_ptr[i]); + putchar('\n'); + free(rr); + } + else + fprintf(stderr, "%s: %s\n", ip, dns_strerror(dns_status(ctx))); +} + +int main(int argc, char **argv) { + int c, t; + time_t now; + int maxq = 10; + struct pollfd pfd; + char linebuf[1024]; + char *eol; + int eof; + + if (dns_init(1) < 0) return 1; + while((c = getopt(argc, argv, "m:r")) != EOF) switch(c) { + case 'm': maxq = atoi(optarg); break; + case 'r': + dns_set_opt(0, DNS_OPT_FLAGS, + dns_set_opt(0, DNS_OPT_FLAGS, -1) | DNS_NORD); + break; + default: return 1; + } + if (argc != optind) return 1; + + pfd.fd = dns_sock(0); + pfd.events = POLLIN; + now = time(NULL); + c = optind; + eof = 0; + while(curq || !eof) { + if (!eof && curq < maxq) { + union { struct in_addr a; void *p; } pa; + if (!fgets(linebuf, sizeof(linebuf), stdin)) { + eof = 1; + continue; + } + eol = strchr(linebuf, '\n'); + if (eol) *eol = '\0'; + if (!linebuf[0]) continue; + if (!inet_aton(linebuf, &pa.a)) + fprintf(stderr, "%s: invalid address\n", linebuf); + else if (dns_submit_a4ptr(0, &pa.a, dnscb, pa.p) == 0) + fprintf(stderr, "%s: unable to submit query: %s\n", + linebuf, dns_strerror(dns_status(0))); + else + ++curq; + continue; + } + if (curq) { + t = dns_timeouts(0, -1, now); + t = poll(&pfd, 1, c * 1000); + now = time(NULL); + if (t) dns_ioevent(0, now); + } + } + return 0; +} diff --git a/libs/udns/rblcheck.1 b/libs/udns/rblcheck.1 new file mode 100644 index 0000000000..0e427e4395 --- /dev/null +++ b/libs/udns/rblcheck.1 @@ -0,0 +1,151 @@ +.\" $Id: rblcheck.1,v 1.1 2005/04/24 23:14:23 mjt Exp $ +.\" rblckeck manpage +.\" +.\" Copyright (C) 2005 Michael Tokarev +.\" This file is part of UDNS library, an async DNS stub resolver. +.\" +.\" This library is free software; you can redistribute it and/or +.\" modify it under the terms of the GNU Lesser General Public +.\" License as published by the Free Software Foundation; either +.\" version 2.1 of the License, or (at your option) any later version. +.\" +.\" This library is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +.\" Lesser General Public License for more details. +.\" +.\" You should have received a copy of the GNU Lesser General Public +.\" License along with this library, in file named COPYING.LGPL; if not, +.\" write to the Free Software Foundation, Inc., 59 Temple Place, +.\" Suite 330, Boston, MA 02111-1307 USA + +.TH rblckeck 1 "Apr 2005" "User Utilities" + +.SH NAME +rblckeck \- DNSBL lookup utility + +.SH SYNOPSYS +.B rblcheck +.RB [\| \-s +.IR zone \|] +.RB [\| \-S +.IR zone\-file \|] +.RB [\| \-c \|] +.RB [\| \-tmvq \|] +.RB [\| \-n +.IR nsaddr \|] +.IR address \|.\|.\|. + +.SH DESCRIPTION +.B rblcheck +is a simple command-line to perform DNSBL (DNS-based blocklists) lookups. +For every IP address (or a name, in which case it will be resolved to an +address first), the utility verifies whenever it is listed in a (list of) +DNS blocklists specified with +.B \-s +or +.B \-S +options, optionally obtains text assotiated with the listing (usually it +is either some description about the reason of the listing or an URL +referring to such a description), and displays results on standard output. +.PP +The program is implemented on top of +.BR udns (3) +library. + +.SH OPTIONS + +The following options are recognized by +.BR rblcheck : + +.TP +.B \-s \fIzone\fR +add the given \fIzone\fR DNSBL name to the list of active zones. +.TP +.B \-S \fIzone-file\fR +add list of zones from the named \fIzone-file\fR to the list of +active zones (the file specifies one zone as the first word on a +line, empty lines and lines starting with `#' character are ignored). +.TP +.B \-c +reset active zone list. +.TP +.B \-v +be more verbose, produce more detailed output. +.TP +.B \-q +the opposite for \fB\-v\fR -- produce less detailed output. +.TP +.B \-t +obtain text for listed addresses. +.TP +.B \-n \fInsaddr\fR +Use the given nameserver (given as IPv4 or IPv6 address) instead of the +default. The same effect may be achieved by setting $NSCACHEIP environment +variable. +.TP +.B \-m +stop after first hit, ie after the first address which is found to be +listed. + +.TP +.B \-h +print short help and exit. + +.PP +If no +.BR \-s , +.BR \-S +and +.B \-c +options are given, +.B rblcheck +will try to obtain list of zones using $RBLCHECK_ZONES environment variable, +or ~/.rblcheckrc, or /etc/rblckechrc files, in that order. If no zones are +found, it will exit unsuccessefully. + +.SH "RETURN VALUE" +When no addresses given are listed and no errors occured, +.B rblcheck +exits with code 0. If at least one address is listed, +.B rblcheck +returns 100. In case of DNS errors, +.B rblcheck +returns 2. + +.SH ENVIRONMENT + +.TP +.B $RBLCHECK_ZONES +if no +.BR \-s , +.B \-S +or +.B \-c +option is given, +.B rblcheck +tries this variable to obtain list of DNSBL zones to check against. + +.SH FILES + +.TP +$HOME/.rblcheckrc and /etc/rblcheckrc +if no +.BR \-s , +.B \-S +or +.B \-c +option is given, and no $RBLCHECK_ZONES environment variable is set, +.B rblcheck +will try the two files (the first one that exists) to obtain list of +DNSBL zones to check against. +Each line specifies one zone (only first word in each line is used). +Empty lines and lines starting with `#' character are ignored. + +.SH "SEE ALSO" +.BR dnsget (1) +.BR resolv.conf (5) +.BR udns (3). + +.SH AUTHOR +This program and manual pages are written by Michael Tokarev. diff --git a/libs/udns/rblcheck.c b/libs/udns/rblcheck.c new file mode 100644 index 0000000000..77bc1bfd7f --- /dev/null +++ b/libs/udns/rblcheck.c @@ -0,0 +1,364 @@ +/* $Id: rblcheck.c,v 1.9 2005/04/24 22:49:10 mjt Exp $ + dnsbl (rbl) checker application + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "udns.h" + +static const char *version = "udns-rblcheck 0.1"; +static char *progname; + +struct rblookup { + struct ipcheck *parent; + struct in_addr key; + const char *zone; + struct dns_rr_a4 *addr; + struct dns_rr_txt *txt; +}; + +struct ipcheck { + const char *name; + int naddr; + int listed; + struct rblookup *lookup; +}; + +#define notlisted ((void*)1) + +static int nzones, nzalloc; +static const char **zones; + +static int do_txt; +static int stopfirst; +static int verbose = 1; +/* verbosity level: + * <0 - only bare As/TXTs + * 0 - what RBL result + * 1(default) - what is listed by RBL: result + * 2 - what is[not ]listed by RBL: result, name lookups + */ + +static int listed; +static int failures; + +static void *ecalloc(int size, int cnt) { + void *t = calloc(size, cnt); + if (!t) { + fprintf(stderr, "%s: out of memory\n", progname); + exit(1); + } + return t; +} + +static void addzone(const char *zone) { + if (nzones >= nzalloc) { + const char **zs = (const char**)ecalloc(sizeof(char*), (nzalloc += 16)); + if (zones) { + memcpy(zs, zones, nzones * sizeof(char*)); + free(zones); + } + zones = zs; + } + zones[nzones++] = zone; +} + +static int addzonefile(const char *fname) { + FILE *f = fopen(fname, "r"); + char linebuf[2048]; + if (!f) + return 0; + while(fgets(linebuf, sizeof(linebuf), f)) { + char *p = linebuf, *e; + while(*p == ' ' || *p == '\t') ++p; + if (*p == '#' || *p == '\n') continue; + e = p; + while(*e && *e != ' ' && *e != '\t' && *e != '\n') + ++e; + *e = '\0'; + addzone(p); + } + fclose(f); + return 1; +} + +static void dnserror(struct rblookup *ipl, const char *what) { + fprintf(stderr, "%s: unable to %s for %s (%s): %s\n", + progname, what, inet_ntoa(ipl->key), ipl->zone, + dns_strerror(dns_status(0))); + ++failures; +} + +static void display_result(struct ipcheck *ipc) { + int j; + struct rblookup *l, *le; + if (!ipc->naddr) return; + for (l = ipc->lookup, le = l + nzones * ipc->naddr; l < le; ++l) { + if (!l->addr) continue; + if (verbose < 2 && l->addr == notlisted) continue; + if (verbose >= 0) { + if (ipc->name) printf("%s[%s]", ipc->name, inet_ntoa(l->key)); + else printf("%s", inet_ntoa(l->key)); + } + if (l->addr == notlisted) { + printf(" is NOT listed by %s\n", l->zone); + continue; + } + else if (verbose >= 1) + printf(" is listed by %s: ", l->zone); + else if (verbose >= 0) + printf(" %s ", l->zone); + if (verbose >= 1 || !do_txt) + for (j = 0; j < l->addr->dnsa4_nrr; ++j) + printf("%s%s", j ? " " : "", inet_ntoa(l->addr->dnsa4_addr[j])); + if (!do_txt) ; + else if (l->txt) { + for(j = 0; j < l->txt->dnstxt_nrr; ++j) { + unsigned char *t = l->txt->dnstxt_txt[j].txt; + unsigned char *e = t + l->txt->dnstxt_txt[j].len; + printf("%s\"", verbose > 0 ? "\n\t" : j ? " " : ""); + while(t < e) { + if (*t < ' ' || *t >= 127) printf("\\x%02x", *t); + else if (*t == '\\' || *t == '"') printf("\\%c", *t); + else putchar(*t); + ++t; + } + putchar('"'); + } + free(l->txt); + } + else + printf("%s", verbose > 0 ? "\n\t" : ""); + free(l->addr); + putchar('\n'); + } + free(ipc->lookup); +} + +static void txtcb(struct dns_ctx *ctx, struct dns_rr_txt *r, void *data) { + struct rblookup *ipl = data; + if (r) { + ipl->txt = r; + ++ipl->parent->listed; + } + else if (dns_status(ctx) != DNS_E_NXDOMAIN) + dnserror(ipl, "lookup DNSBL TXT record"); +} + +static void a4cb(struct dns_ctx *ctx, struct dns_rr_a4 *r, void *data) { + struct rblookup *ipl = data; + if (r) { + ipl->addr = r; + ++listed; + if (do_txt) { + if (dns_submit_a4dnsbl_txt(0, &ipl->key, ipl->zone, txtcb, ipl)) + return; + dnserror(ipl, "submit DNSBL TXT record"); + } + ++ipl->parent->listed; + } + else if (dns_status(ctx) != DNS_E_NXDOMAIN) + dnserror(ipl, "lookup DNSBL A record"); + else + ipl->addr = notlisted; +} + +static int +submit_a_queries(struct ipcheck *ipc, + int naddr, const struct in_addr *addr) { + int z, a; + struct rblookup *rl = ecalloc(sizeof(*rl), nzones * naddr); + ipc->lookup = rl; + ipc->naddr = naddr; + for(a = 0; a < naddr; ++a) { + for(z = 0; z < nzones; ++z) { + rl->key = addr[a]; + rl->zone = zones[z]; + rl->parent = ipc; + if (!dns_submit_a4dnsbl(0, &rl->key, rl->zone, a4cb, rl)) + dnserror(rl, "submit DNSBL A query"); + ++rl; + } + } + return 0; +} + +static void namecb(struct dns_ctx *ctx, struct dns_rr_a4 *rr, void *data) { + struct ipcheck *ipc = data; + if (rr) { + submit_a_queries(ipc, rr->dnsa4_nrr, rr->dnsa4_addr); + free(rr); + } + else + fprintf(stderr, "%s: unable to lookup %s: %s\n", + progname, ipc->name, dns_strerror(dns_status(ctx))); +} + +static int submit(struct ipcheck *ipc) { + struct in_addr addr; + if (inet_aton(ipc->name, &addr)) { + submit_a_queries(ipc, 1, &addr); + ipc->name = NULL; + } + else if (!dns_submit_a4(0, ipc->name, 0, namecb, ipc)) + fprintf(stderr, "%s: unable to submit name query for %s: %s\n", + progname, ipc->name, dns_strerror(dns_status(0))); + return 0; +} + +static void waitdns(struct ipcheck *ipc) { + struct timeval tv; + fd_set fds; + int c; + int fd = dns_sock(NULL); + time_t now = 0; + FD_ZERO(&fds); + while((c = dns_timeouts(NULL, -1, now)) > 0) { + FD_SET(fd, &fds); + tv.tv_sec = c; + tv.tv_usec = 0; + c = select(fd+1, &fds, NULL, NULL, &tv); + now = time(NULL); + if (c > 0) + dns_ioevent(NULL, now); + if (stopfirst && ipc->listed) + break; + } +} + +int main(int argc, char **argv) { + int c; + struct ipcheck ipc; + char *nameserver = NULL; + int zgiven = 0; + + if (!(progname = strrchr(argv[0], '/'))) progname = argv[0]; + else argv[0] = ++progname; + + while((c = getopt(argc, argv, "hqtvms:S:cn:")) != EOF) switch(c) { + case 's': ++zgiven; addzone(optarg); break; + case 'S': + ++zgiven; + if (addzonefile(optarg)) break; + fprintf(stderr, "%s: unable to read %s\n", progname, optarg); + return 1; + case 'c': ++zgiven; nzones = 0; break; + case 'q': --verbose; break; + case 'v': ++verbose; break; + case 't': do_txt = 1; break; + case 'n': nameserver = optarg; break; + case 'm': ++stopfirst; break; + case 'h': + printf("%s: %s.\n", progname, version); + printf("Usage is: %s [options] address..\n", progname); + printf( +"Where options are:\n" +" -h - print this help and exit\n" +" -s service - add the service (DNSBL zone) to the serice list\n" +" -S service-file - add the DNSBL zone(s) read from the given file\n" +" -c - clear service list\n" +" -v - increase verbosity level (more -vs => more verbose)\n" +" -q - decrease verbosity level (opposite of -v)\n" +" -t - obtain and print TXT records if any\n" +" -m - stop checking after first address match in any list\n" +" -n ipaddr - use the given nameserver instead of the default\n" +"(if no -s or -S option is given, use $RBLCHECK_ZONES, ~/.rblcheckrc\n" +"or /etc/rblcheckrc in that order)\n" + ); + return 0; + default: + fprintf(stderr, "%s: use `%s -h' for help\n", progname, progname); + return 1; + } + + if (!zgiven) { + char *s = getenv("RBLCHECK_ZONES"); + if (s) { + char *k; + s = strdup(s); + k = strtok(s, " \t"); + while(k) { + addzone(k); + k = strtok(NULL, " \t"); + } + free(s); + } + else { + char *path; + char *home = getenv("HOME"); + if (!home) home = "."; + path = malloc(strlen(home) + 1 + sizeof(".rblcheckrc")); + sprintf(path, "%s/.rblcheckrc", home); + if (!addzonefile(path)) + addzonefile("/etc/rblcheckrc"); + free(path); + } + } + if (!nzones) { + fprintf(stderr, "%s: no service (zone) list specified (-s or -S option)\n", + progname); + return 1; + } + + argv += optind; + argc -= optind; + + if (!argc) + return 0; + + if (dns_init(0) < 0) { + fprintf(stderr, "%s: unable to initialize DNS library: %s\n", + progname, strerror(errno)); + return 1; + } + if (nameserver) { + dns_add_serv(NULL, NULL); + if (dns_add_serv(NULL, nameserver) < 0) + fprintf(stderr, "%s: unable to use nameserver %s: %s\n", + progname, nameserver, strerror(errno)); + } + if (dns_open(NULL) < 0) { + fprintf(stderr, "%s: unable to initialize DNS library: %s\n", + progname, strerror(errno)); + return 1; + } + + for (c = 0; c < argc; ++c) { + if (c && (verbose > 1 || (verbose == 1 && do_txt))) putchar('\n'); + ipc.name = argv[c]; + submit(&ipc); + waitdns(&ipc); + display_result(&ipc); + if (stopfirst > 1 && listed) break; + } + + return listed ? 100 : failures ? 2 : 0; +} diff --git a/libs/udns/udns.3 b/libs/udns/udns.3 new file mode 100644 index 0000000000..06d2a146c4 --- /dev/null +++ b/libs/udns/udns.3 @@ -0,0 +1,1284 @@ +.\" $Id: udns.3,v 1.26 2006/11/28 22:58:04 mjt Exp $ +.\" udns library manpage +.\" +.\" Copyright (C) 2005 Michael Tokarev +.\" This file is part of UDNS library, an async DNS stub resolver. +.\" +.\" This library is free software; you can redistribute it and/or +.\" modify it under the terms of the GNU Lesser General Public +.\" License as published by the Free Software Foundation; either +.\" version 2.1 of the License, or (at your option) any later version. +.\" +.\" This library is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +.\" Lesser General Public License for more details. +.\" +.\" You should have received a copy of the GNU Lesser General Public +.\" License along with this library, in file named COPYING.LGPL; if not, +.\" write to the Free Software Foundation, Inc., 59 Temple Place, +.\" Suite 330, Boston, MA 02111-1307 USA + +.TH udns 3 "Apr 2005" "Library Functions" + +.SH NAME +udns \- stub DNS resolver library + +.SH SYNOPSYS +.nf +#include +struct \fBdns_ctx\fR; +struct \fBdns_query\fR; +extern struct dns_ctx \fBdns_defctx\fR; +struct dns_ctx *\fIctx\fR; +typedef void \fBdns_query_fn\fR(\fIctx\fR, void *\fIresult\fR, void *\fIdata\fR); +typedef int +\fBdns_parse_fn\fR(const unsigned char *\fIqnd\fR, + const unsigned char *\fIpkt\fR, + const unsigned char *\fIcur\fR, + const unsigned char *\fIend\fR, + void **\fIresultp\fR); + +\fBcc\fR ... -l\fBudns\fR +.fi + +.SH DESCRIPTION + +.PP +The DNS library, \fBudns\fR, implements thread-safe stub DNS resolver +functionality, which may be used both traditional, syncronous way +and asyncronously, with application-supplied event loop. + +.PP +While DNS works with both TCP and UDP, performing UDP query first and +if the result does not fit in UDP buffer (512 bytes max for original +DNS protocol), retrying the query over TCP, the library uses UDP only, +but uses EDNS0 (RFC2671) extensions which allows larger UDP buffers. + +.PP +The library uses single UDP socket to perform all operations even when +asking multiple nameservers. This way, it is very simple to use the +library in asyncronous event-loop applications: an application should +add only single socket to the set of filedescriptors it monitors for I/O. + +.PP +The library uses two main objects, \fIresolver context\fR of type +\fBstruct\ dns_ctx\fR, and \fIquery structure\fR of type +\fBstruct\ dns_query\fR, both are opaque for an application. +Resolver context holds global information about the resolver, +such as list of nameservers to use, list of active requests and the like. +Query objects holds information about a single DNS query in progress and +are allocated/processed/freed by the library. Pointer to query structure +may be treated as an identifier of an in-progress query and may be used +to cancel the asyncronous query or to wait for it to complete. + +.PP +Asyncronous interface works as follows. An application initializes +resolver context, submits any number of queries for it using one of +supplied \fBdns_submit_\fIXXX\fR() routines (each return the query +identifier as pointer to query structure), waits for input on the +UDP socket used by the library, and gives some control to the library +by calling \fBdns_ioevent\fR() and \fBdns_timeouts\fR() routines when +appropriate. The library performs all necessary processing and executes +application supplied callback routine when a query completes (either +successefully or not), giving it the result if any, pointer to the +resolver context (from which completion status may be obtained), and +the data pointer supplied by an application when the query has been +submitted. When submitting a query, an application requests how to +handle the reply -- to either return raw DNS reply packet for its +own low-level processing, or it may provide an address of \fIparsing +routine\fR of type \fBdns_parse_fn\fR to perform conversion of on-wire +format into easy to use data structure (the library provides parsing +routines for several commonly used resource record types, as well as +type-safe higher-level inteface that requests parsing automatically). +The I/O monitoring and timeout handling may be either traditional +select() or poll() based, or any callback-driven technique may be +used. + +.PP +Additionally, the library provides traditional syncronous interface, +which may be intermixed with asyncronous calls (during syncronous +query processing, other asyncronous queries for the same resolver +context continued to be processed as usual). An application uses +one of numerous \fBdns_resolve_\fIXXX\fR() routines provided by the +library to perform a query. As with asyncronous interface, an +application may either request to return raw DNS packet or type-specific +data structure by providing the parsing routine to handle the reply. +Every routine from \fBdns_resolve_\fIXXX\fR() series return pointer +to result or NULL in case of any error. Query completion status +(or length of the raw DNS packet) is available from the resolver +context using \fBdns_status\fR() routine, the same way as for the +asyncronous interface. + +.PP +Internally, library uses on-wire format of domain names, referred +to as \fIDN format\fR in this manual page. This is a series of domain +\fIlabels\fR whith preceeding length byte, terminated by zero-length +label wich is integral part of the DN format. There are several routines +provided to convert from traditional asciiz string to DN and back. +Higher-level type-specific query interface hides the DN format from +an application. + +.SH "COMMON DEFINITIONS" + +.PP +Every DNS Resource Record (RR) has a \fItype\fR and a \fIclass\fR. +The library defines several integer constants, \fBDNS_C_\fIXXX\fR and +\fBDNS_T_\fIXXX\fR, to use as symbolic names for RR classes and types, +such as \fBDNS_C_IN\fR for Internet class, \fBDNS_T_A\fR for IPv4 +address record type and so on. See udns.h header file for complete list +of all such constants. + +.PP +The following constants are defined in dns.h header file: +.IP "\fBDNS_MAXDN\fR (255 bytes)" +Maximum length of the domain name in internal (on-wire) DN format. +.IP "\fBDNS_MAXLABEL\fR (63 bytes)" +Maximum length of a single label in DN format. +.IP "\fBDNS_MAXNAME\fR (1024 bytes)" +Maximum length of asciiz format of a domain name. +.IP "\fBDNS_HSIZE\fR (12 bytes)" +Size of header in DNS packet. +.IP "\fBDNS_PORT\fR (53)" +Default port to use when contacting a DNS server. +.IP "\fBDNS_MAXSERV\fR (6 servers)" +Maximum number of DNS servers to use. +.IP "\fBDNS_MAXSRCH\fR (5 search list entries)" +Maximum number of domain search list +.IP "\fBDNS_MAXPACKET\fR (512 bytes)" +Maximum length of DNS UDP packet as specified by original DNS protocol +.IP "\fBDNS_EDNS0PACKET\fR (4096 bytes)" +Default length of DNS UDP packet (with EDNS0 extensions) the library uses. +Note that recursive nameservers usually resides near the client asking them +to resolve names, e.g. on the same LAN segment or even on the same host, so +UDP packet fragmentation isn't a problem in most cases. Note also that +the size of actual packets will be as many bytes as actual reply size requires, +which is smaller than this value in almost all cases. + +.PP +Additionally, several constants are defined to simplify work with raw DNS +packets, such as DNS response codes (\fBDNS_R_\fIXXX\fR), DNS header layout +(\fBDNS_H_\fIXXX\fR) and others. Again, see udns.h for complete list. +Library error codes (\fBDNS_E_\fIXXX\fR) are described later in this +manual page. + +.SH "RESOLVER CONTEXT" + +.PP +Resolver context, of type \fBstruct\ dns_ctx\fR, is an object which is +opaque to an application. Several routines provided by the library +to initialize, copy and free resolver contexts. Most other high-level +routines in this library expects a pointer to resolver context, \fIctx\fR, +as the first argument. There is a default resolver context available, +named \fBdns_defctx\fR. When the context pointer \fIctx\fR passed to +a routine is NULL, \fBdns_defctx\fR is used. Several resolver contexts +may be active at the same time, for example, when an application is +multi-threaded and each thread uses resolver. +.PP +When initializing resolver context, the library uses information from +system file /etc/resolv.conf (see \fBresolv.conf\fR(5)), consults +environment variables \fB$LOCALDOMAIN\fR, \fB$DNSCACHEIP\fR, +\fB$NAMESERVERS\fR and \fB$RES_OPTIONS\fR, and local host name to obtain +list of local nameservers, domain name search list and various resolver +options. +.PP +The following routines to initialize resolver context are available: +.PP +.nf +int \fBdns_init\fR(int \fIdo_open\fR) +struct dns_ctx *\fBdns_new\fR(struct dns_ctx *\fIcopy\fR) +void \fBdns_free\fR(\fIctx\fR) +.fi +.RS +\fBdns_init\fR() initializes default resolver context, \fBdns_defctx\fR, +and optionally opens it (if \fIdo_open\fR is true) using \fBdns_open\fR(), +returning negative value on error. +\fBdns_new\fR() makes a copy of a given resolver context \fIcopy\fR, or +default context if \fIcopy\fR is NULL, and returns pointer to it. +\fBdns_new\fR() may fail if there's no memory available to make a copy +of \fIcopy\fR, in which case the routine will return NULL pointer. +\fBdns_free\fR() is used to close assotiated socket and free resolver +context resources and cancelling (abandoming) all active queries +assotiated with it. It's ok to free \fBdns_defctx\fR as well as +dynamically allocated contexts returned by \fBdns_new\fR(). +.RE +.PP +.nf +int \fBdns_add_serv\fR(\fIctx\fR, const char *\fIserv\fR) +int \fBdns_add_serv_s\fR(\fIctx\fR, const struct sockaddr *\fIsa\fR) +int \fBdns_add_srch\fR(\fIctx\fR, const char *\fIsrch\fR) +.fi +.RS +Add an element to list of nameservers (\fBdns_add_serv\fR(), as +asciiz-string \fIserv\fR with an IP address of the nameserver, +and \fBdns_add_serv_s\fR(), as initialized socket address \fIsa\fR), +or search list (\fBdns_add_srch\fR(), as a pointer to domain name) +for the given context \fIctx\fR. If the last argument is a NULL +pointer, the corresponding list (search or nameserver) is reset +instead. Upon successeful completion, each routine returns new +number of elements in the list in question. On error, negative +value is returned and global variable \fBerrno\fR is set appropriately. +It is an error to call any of this functions if the context is +opened (after \fBdns_open\fR() or \fBdns_init\fR() with non-zero argument). +.RE +.PP +.nf +int \fBdns_set_opts\fR(\fIctx\fR, const char *\fIopts\fR) +.fi +.RS +set resolver context options from \fIopts\fR string, in the same way as +processing \fBoptions\fR statement in resolv.conf and \fB$RES_OPTIONS\fR +environment variable. +.RE +.PP +.nf +void \fBdns_set_opt\fR(\fIctx\fR, int \fIopt\fR, \fIval\fR) +.fi +.RS +.B TODO +The \fIflags\fR argument is a bitmask with the following bits defined: +.IP \fBDNS_NOSRCH\fR +do not perform domain name search in search list. +.IP \fBDNS_NORD\fR +do not request recursion when performing queries +(i.e. don't set RD flag in querues). +.IP \fBDNS_AAONLY\fR +request authoritative answers only (i.e. set AA +flag in queries). +.RE + +.PP +.nf +int \fBdns_open\fR(\fIctx\fR) +int \fBdns_sock\fR(const \fIctx\fR) +void \fBdns_close\fR(\fIctx\fR) +.fi +.RS +\fBdns_open\fR() opens the UDP socket used for queries if not already +open, and return assotiated filedescriptor (or negative value in case +of error). +\fBdns_sock\fR() return the UDP socket if open, or -1 if not. +\fBdns_close\fR() closes the UDP socket if it was open. +.RE + +.PP +.nf +int \fBdns_active\fR(const \fIctx\fR) +.fi +.RS +return number of active queries queued for the given context +\fIctx\fR, or zero if none. +.RE + +.PP +.nf +int \fBdns_status\fR(const \fIctx\fR) +.fi +.RS +return status code from last operation. When using syncronous +interface, this is the query completion status of the last query. +With asyncronous interface, from within the callback routine, +this is the query completion status of the query for which the +callback is being called. When query submission fails, this +is the error code indicating failure reason. All error codes +are negative and are represented by \fBDNS_E_\fIXXX\fR constants +described below. +.RE + +.PP +.nf +void \fBdns_ioevent\fR(\fIctx\fR, time_t \fInow\fR) +.fi +.RS +this routine may be called by an application to process I/O +events on the UDP socket used by the library, as returned +by \fBdns_sock\fR(). The routine tries to receive incoming +UDP datagram from the socket and process it. The socket is +set up to be non-blocking, so it is safe to call the routine +even if there's no data to read. The routine will process +as many datagrams as are queued for the socket, so it is +safe to use it with either level-triggered or edge-triggered +I/O monitoring model. The \fInow\fR argument is either a +current time as returned by \fBtime\fR(), or 0, in which +case the routine will obtain current time by it's own. +.RE + +.PP +.nf +int \fBdns_timeouts\fR(\fIctx\fR, int \fImaxwait\fR, time_t \fInow\fR) +.fi +.RS +process any pending timeouts and return number of secounds +from current time (\fInow\fR if it is not 0) to the time when +the library wants the application to pass it control to process +more queued requests. In case when there are no requests pending, +this time is -1. The routine will not request a time larger than +\fImaxwait\fR secounds if it is greather or equal to zero. If +\fInow\fR is 0, the routine will obtain current time by it's own; +when it is not 0, it should contain current time as returned by +\fBtime\fR(). +.RE + +.PP +.nf +typedef void \fBdns_utm_fn\fR(\fIctx\fR, int \fItimeout\fR, void *\fIdata\fR) +void \fBdns_set_cbck\fR(\fIctx\fR, dns_utm_fn *\fIutmfn\fR, void *\fIdata\fR) +.fi +.RS +An application may use custom callback-based I/O multiplexing mechanism. +Usually such a mechanism have concept of a \fItimer\fR, and an ability +to register a timer event in a form of a callback routine which will +be executed after certain amount of time. In order to use such an +event mechanism, udns provides an ability to register and de-register +timer events necessary for internal processing using whatever event +mechanism an application uses. For this to work, it is possible to +assotiate a pointer to a routine that will perform necessary work for +(de)registering timer events with a given resolver context, and +udns will call that routine at appropriate times. Prototype of +such a routine is shown by \fBdns_utm_fn\fR typedef above. Libudns +assotiates single timer with resolver context. User-supplied \fIutmfn\fR +routine will be called by the library with the following arguments: +.IP "\fIctx\fR == NULL" +delete user timer, at context free time or when an application changes +user timer request routine using \fBdns_set_cbck\fR(); +.IP "\fIctx\fR != NULL, \fItimeout\fR < 0" +don't fire timer anymore, when there are no active requests; +.IP "\fIctx\fR != NULL, \fItimeout\fR == 0" +fire timer at the next possibility, but not immediately; +.IP "\fIctx\fR != NULL, \fItimeout\fR > 0" +fire timer after \fItimeout\fR seconds after now. +.PP +The \fIdata\fR argument passed to the routine will be the same +as passed to \fBdns_set_cbck\fR(). +.PP +When a timer expires, an application should call \fBdns_tmeouts\fR() +routine (see below). Non-callback timer usage is provided too. +.RE + +.PP +.B XXXX TODO: some more resolver context routines, like dns_set_dbgfn() etc. + +.SH "QUERY INTERFACE" + +.PP +There are two ways to perform DNS queries: traditional syncronous +way, when udns performs all the necessary processing and return +control to the application only when the query completes, and +asyncronous way, when an application submits one or more queries +to the library using given resolver context, and waits for completion +by monitoring filedescriptor used by library and calling library +routines to process input on that filedescriptor. Asyncronous mode +works with callback routines: an application supplies an address of +a routine to execute when the query completes, and a data pointer, +which is passed to the callback routine. + +.PP +Queries are submitted to the library in a form of \fBstruct\ dns_query\fR. +To perform asyncronous query, an application allocates memory for the +\fIquery structure\fR and passes it to the library using \fBdns_submit\fR() +routines, together with all the query parameters. When the query completes, +library will call application-supplied callback routine, giving it the +resolver context (wich holds query completion status), dynamically allocated +result (which will be either raw DNS packet or, if applicatin requested parsing +the result by specifying non-NULL parse routine, ready-to-use type-specific +structure), and a data pointer provided by an application when it submitted the +query. It is the application who's responsible for freeing the result memory. +.PP +Generic query callback routine looks like this: +.nf +typedef void +\fBdns_query_fn\fR(\fIctx\fR, void *\fIresult\fR, void *\fIdata\fR) +.fi +Type-specific query interface expects similar form of callback +routine with the only difference in type of \fBresult\fR argument, +which will be pointer to specific data structure (decoded reply) +instead of this void pointer to raw DNS packet data. + +.PP +Result parsing routine looks like this: +.nf +typedef int +\fBdns_parse_fn\fR(const unsigned char *\fIqdn\fR, + const unsigned char *\fIpkt\fR, + const unsigned char *\fIcur\fR, + const unsigned char *\fIend\fR, + void **\fIresultp\fR); +.fi +When called by the library, the arguments are as follows: +\fIpkt\fR points to the start of the packet received; +\fIend\fR points past the end of the packet received; +\fIcur\fR points past the query DN in the query section of the +packet; +\fIqdn\fR points to the original query DN. +The routine should allocate a single buffer to hold the result, +parse the reply filling in the buffer, and return the buffer +using \fIresultp\fR argument. It returns 0 in case of error, +or udns error code (\fBDNS_E_\fIXXX\fR constants) in case of +error. +Note that by the time when the parse routine is called by the +library, packet is already verified to be a reply to the +original query, by matching query DN, query class and query type. + +.PP +Type-specific query inteface supplies necessary parsing routines +automatically. + +.PP +In case of error, query completion status as returned by +\fBdns_status\fR(\fIctx\fR), will contain one of the following values: +.IP "positive value" +length of raw DNS packet if parsing is not requested. +.IP 0 +the query was successeful and the \fIreply\fR points to type-specific +data structure. +.IP \fBDNS_E_TEMPFAIL\fR +temporary error, the resolver nameserver was not able to +process our query or timed out. +.IP \fBDNS_E_PROTOCOL\fR +protocol error, a nameserver returned malformed reply. +.IP \fBDNS_E_NXDOMAIN\fR +the domain name does not exist. +.IP \fBDNS_E_NODATA\fR +there is no data of requested type found. +.IP \fBDNS_E_NOMEM\fR +out of memory while processing request. +.IP \fBDNS_E_BADQUERY\fR +some aspect of the query (most common is the domain name in question) +is invalid, and the library can't even start a query. + +.PP +Library provides two series of routines which uses similar interface -- +one for asyncronous queries and another for syncronous queries. There +are two general low-level routines in each series to submit (asyncronous +interface) and resolve (syncronous interface) queries, as well as several +type-specific routines with more easy-to-use interfaces. To submit +an asyncronous query, use one of \fBdns_submit_\fIXXX\fR() routine, each +of which accepts query parameters, pointers to callback routine and to +callback data, and optional current time hint. Note type-specific +\fBdns_submit_\fIXXX\fR() routines expects specific type of the callback +routine as well, which accepts reply as a pointer to corresponding +structure, not a void pointer). Every \fBdns_submit_\fIXXX\fR() routine +return pointer to internal query structure of type struct\ dns_query, +used as an identifier for the given query. + +.PP +To resolve a query syncronously, use one of \fBdns_resolve_\fIXXX\fR() +routines, which accepts the same query parameters (but not the +callback pointers) as corresponding \fBdns_submit_\fIXXX\fR(), and +return the query result, which is the same as passed to the callback +routine in case of asyncronous interface. + +.PP +In either case, the result memory (if the query completed successefully) +is dynamically allocated and should be freed by an application. If +the query failed for any reason, the result will be NULL, and error +status will be available from \fBdns_status\fR(\fIctx\fR) routine +as shown above. + +.PP +.nf +struct dns_query * +\fBdns_submit_dn\fR(\fIctx\fR, + const unsigned char *\fIdn\fR, \fIqcls\fR, \fIqtyp\fR, \fIflags\fR, + \fIparse\fR, \fIcbck\fR, \fIdata\fR) +struct dns_query * +\fBdns_submit_p\fR(\fIctx\fR, + const char *\fIname\fR, \fIqcls\fR, \fIqtyp\fR, \fIflags\fR, + \fIparse\fR, \fIcbck\fR, \fIdata\fR) + enum dns_class \fIqcls\fR; + enum dns_type \fIqtyp\fR; + int \fIflags\fR; + dns_parse_fn *\fIparse\fR; + dns_query_fn *\fIcbck\fR; + void *\fIdata\fR; +.fi +.RS +submit a query for processing for the given resolver context \fIctx\fR. +Two routines differs only in 3rd argument, which is domain name in +DN format (\fIdn\fR) or asciiz string (\fIname\fR). The query will be +performed for the given domain name, with type \fIqtyp\fR in class \fIqcls\fR, +using option bits in \fIflags\fR, using RR parsing routine pointed by +\fIparse\fR if not-NULL, and upon completion, \fIcbck\fR function will +be called with the \fIdata\fR argument. +In case of successeful query submission, +the routine return pointer to internal query structure which may be treated +as an identifier of the query as used by the library, and may be used as an +argument for \fBdns_cancel\fR() routine. In case of error, NULL will be +returned, and context error status (available using \fIdns_status\fR() routine) +will be set to corresponding error code, which in this case may be +DNS_E_BADQUERY if the \fIname\fR of \fIdn\fR is invalid, DNS_E_NOMEM if +there's no memory available to allocate query structure, or DNS_E_TEMPFAIL +if an internal error occured. +.RE + +.PP +.nf +void *\fBdns_resolve_dn\fR(\fIctx\fR, + const unsigned char *\fIdn\fR, \fIqcls\fR, \fIqtyp\fR, \fIflags\fR, \fIparse\fR); +void *\fBdns_resolve_p\fR(\fIctx\fR, + const char *\fIname\fR, \fIqcls\fR, \fIqtyp\fR, \fIflags\fR, \fIparse\fR) + enum dns_class \fIqcls\fR; + enum dns_type \fIqtyp\fR; + int \fIflags\fR; + dns_parse_fn *\fIparse\fR; +.fi +.RS +syncronous interface. The routines perform all the steps necessary to resolve +the given query and return the result. If there's no positive result for any +reason, all the routines return NULL, and set context error status (available +using \fBdns_status\fR() routine) to indicate the error code. If the query +was successeful, context status code will contain either the length of the +raw DNS reply packet if \fIparse\fR argument was NULL (in which case the return +value is pointer to the reply DNS packet), or 0 (in which case the return value +is the result of \fIparse\fR routine). If the query successeful (return value +is not NULL), the memory returned was dynamically allocated by the library +and should be free()d by application after use. +.RE + +.PP +.nf +void *\fBdns_resolve\fR(\fIctx\fR, struct dns_query *\fIq\fR) +.fi +.RS +wait for the given query \fIq\fR, as returned by one of +\fBdns_submit_\fIXXX\fR() routines, for completion, and +return the result. The callback routine will not be called +for this query. After completion, the query identifier \fIq\fI +is not valid. Both \fBdns_resolve_dn\fR() and \fBdns_resolve_p\fR() +are just wrappers around corresponding submit routines and this +\fBdns_resolve\fR() routine. +.RE + +.PP +.nf +void \fBdns_cancel\fR(\fIctx\fR, struct dns_query *\fIq\fR) +.fi +.RS +cancel an active query \fIq\fR, without calling a callback routine. +After completion, the query identifier \fIq\fR is not valid. +.RE + +.SH "TYPE-SPECIFIC QUERIES" + +.PP +In addition to the generic low-level query interface, the library provides +a set of routines to perform specific queries in a type-safe manner, as +well as parsers for several well-known resource record types. The library +implements high-level interface for A, AAAA, PTR, MX and TXT records +and DNSBL and RHSBL functionality. These routines returns specific types +as result of a query, instead of raw DNS packets. The following types +and routines are available. + +.PP +.nf +struct \fBdns_rr_null\fR { + char *\fBdnsn_qname\fR; /* original query name */ + char *\fBdnsn_cname\fR; /* canonical name */ + unsigned \fBdnsn_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnsn_nrr\fR; /* number of records in the set */ +}; +.fi +.PP +NULL RR set, used as a base for all other RR type structures. +Every RR structure as used by the library have four standard +fields as in struct\ \fBdns_rr_null\fR. + +.SS "IN A Queries" +.PP +.nf +struct \fBdns_rr_a4\fR { /* IN A RRset */ + char *\fBdnsa4_qname\fR; /* original query name */ + char *\fBdnsa4_cname\fR; /* canonical name */ + unsigned \fBdnsa4_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnsa4_nrr\fR; /* number of addresses in the set */ + struct in_addr \fBdnsa4_addr\fR[]; /* array of addresses */ +}; +typedef void + \fBdns_query_a4_fn\fR(\fIctx\fR, struct dns_rr_a4 *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_a4\fB; +struct dns_query * +\fBdns_submit_a4\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR, + dns_query_a4_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_a4 * +\fBdns_resolve_a4\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR); +.fi +.PP +The \fBdns_rr_a4\fR structure holds a result of an \fBIN A\fR query, +which is an array of IPv4 addresses. Callback routine for IN A queries +expected to be of type \fBdns_query_a4_fn\fR, which expects pointer to +\fBdns_rr_a4\fR structure as query result instead of raw DNS packet. +The \fBdns_parse_a4\fR() is used to convert raw DNS reply packet into +\fBdns_rr_a4\fR structure (it is used internally and may be used directly too +with generic query interface). Routines \fBdns_submit_a4\fR() and +\fBdns_resolve_a4\fR() are used to perform A IN queries in a type-safe +manner. The \fIname\fR parameter is the domain name in question, and +\fIflags\fR is query flags bitmask, with one bit, DNS_NOSRCH, of practical +interest (if the \fIname\fR is absolute, that is, it ends up with a dot, +DNS_NOSRCH flag will be set automatically). + +.SS "IN AAAA Queries" +.PP +.nf +struct \fBdns_rr_a6\fR { /* IN AAAA RRset */ + char *\fBdnsa6_qname\fR; /* original query name */ + char *\fBdnsa6_cname\fR; /* canonical name */ + unsigned \fBdnsa6_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnsa6_nrr\fR; /* number of addresses in the set */ + struct in6_addr \fBdnsa6_addr\fR[]; /* array of addresses */ +}; +typedef void + \fBdns_query_a6_fn\fR(\fIctx\fR, struct dns_rr_a6 *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_a6\fB; +struct dns_query * +\fBdns_submit_a6\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR, + dns_query_a6_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_a6 * +\fBdns_resolve_a6\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR); +.fi +.PP +The \fBdns_rr_a6\fR structure holds a result of an \fBIN AAAA\fR query, +which is an array of IPv6 addresses. Callback routine for IN AAAA queries +expected to be of type \fBdns_query_a6_fn\fR, which expects pointer to +\fBdns_rr_a6\fR structure as query result instead of raw DNS packet. +The \fBdns_parse_a6\fR() is used to convert raw DNS reply packet into +\fBdns_rr_a6\fR structure (it is used internally and may be used directly too +with generic query interface). Routines \fBdns_submit_a6\fR() and +\fBdns_resolve_a6\fR() are used to perform AAAA IN queries in a type-safe +manner. The \fIname\fR parameter is the domain name in question, and +\fIflags\fR is query flags bitmask, with one bit, DNS_NOSRCH, of practical +interest (if the \fIname\fR is absolute, that is, it ends up with a dot, +DNS_NOSRCH flag will be set automatically). + +.SS "IN PTR Queries" +.PP +.nf +struct \fBdns_rr_ptr\fR { /* IN PTR RRset */ + char *\fBdnsptr_qname\fR; /* original query name */ + char *\fBdnsptr_cname\fR; /* canonical name */ + unsigned \fBdnsptr_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnsptr_nrr\fR; /* number of domain name pointers */ + char *\fBdnsptr_ptr\fR[]; /* array of domain name pointers */ +}; +typedef void + \fBdns_query_ptr_fn\fR(\fIctx\fR, struct dns_rr_ptr *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_ptr\fB; +struct dns_query * +\fBdns_submit_a4ptr\fB(\fIctx\fR, const struct in_addr *\fBaddr\fR, + dns_query_ptr_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_ptr * +\fBdns_resolve_a4ptr\fB(\fIctx\fR, const struct in_addr *\fBaddr\fR); +struct dns_query * +\fBdns_submit_a6ptr\fB(\fIctx\fR, const struct in6_addr *\fBaddr\fR, + dns_query_ptr_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_ptr * +\fBdns_resolve_a6ptr\fB(\fIctx\fR, const struct in6_addr *\fBaddr\fR); +.fi +.PP +The \fBdns_rr_ptr\fR structure holds a result of an IN PTR query, which +is an array of domain name pointers for a given IPv4 or IPv6 address. +Callback routine for IN PTR queries expected to be of type +\fBdns_query_ptr_fn\fR, which expects pointer to \fBdns_rr_ptr\fR +structure as query result instead of raw DNS packet. The \fBdns_parse_ptr\fR() +is used to convert raw DNS reply packet into \fBdns_rr_ptr\fR structure +(it is used internally and may be used directly too with generic query +interface). Routines \fBdns_submit_a4ptr\fR() and \fBdns_resolve_a4ptr\fR() +are used to perform IN PTR queries for IPv4 addresses in a type-safe +manner. Routines \fBdns_submit_a6ptr\fR() and \fBdns_resolve_a6ptr\fR() +are used to perform IN PTR queries for IPv6 addresses. + +.SS "IN MX Queries" +.PP +.nf +struct \fBdns_mx\fR { /* single MX record */ + int \fBpriority\fR; /* priority value of this MX */ + char *\fBname\fR; /* domain name of this MX */ +}; +struct \fBdns_rr_mx\fR { /* IN MX RRset */ + char *\fBdnsmx_qname\fR; /* original query name */ + char *\fBdnsmx_cname\fR; /* canonical name */ + unsigned \fBdnsmx_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnsmx_nrr\fR; /* number of mail exchangers in the set */ + struct dns_mx \fBdnsmx_mx\fR[]; /* array of mail exchangers */ +}; +typedef void + \fBdns_query_mx_fn\fR(\fIctx\fR, struct dns_rr_mx *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_mx\fB; +struct dns_query * +\fBdns_submit_mx\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR, + dns_query_mx_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_mx * +\fBdns_resolve_mx\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR); +.fi +.PP +The \fBdns_rr_mx\fR structure holds a result of an IN MX query, which +is an array of mail exchangers for a given domain. Callback routine for IN MX +queries expected to be of type \fBdns_query_mx_fn\fR, which expects pointer to +\fBdns_rr_mx\fR structure as query result instead of raw DNS packet. +The \fBdns_parse_mx\fR() is used to convert raw DNS reply packet into +\fBdns_rr_mx\fR structure (it is used internally and may be used directly too +with generic query interface). Routines \fBdns_submit_mx\fR() and +\fBdns_resolve_mx\fR() are used to perform IN MX queries in a type-safe +manner. The \fIname\fR parameter is the domain name in question, and +\fIflags\fR is query flags bitmask, with one bit, DNS_NOSRCH, of practical +interest (if the \fIname\fR is absolute, that is, it ends up with a dot, +DNS_NOSRCH flag will be set automatically). + +.SS "TXT Queries" +.PP +.nf +struct \fBdns_txt\fR { /* single TXT record */ + int \fBlen\fR; /* length of the text */ + unsigned char *\fBtxt\fR; /* pointer to the text */ +}; +struct \fBdns_rr_txt\fR { /* TXT RRset */ + char *\fBdnstxt_qname\fR; /* original query name */ + char *\fBdnstxt_cname\fR; /* canonical name */ + unsigned \fBdnstxt_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnstxt_nrr\fR; /* number of text records in the set */ + struct dns_txt \fBdnstxt_txt\fR[]; /* array of TXT records */ +}; +typedef void + \fBdns_query_txt_fn\fR(\fIctx\fR, struct dns_rr_txt *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_txt\fB; +struct dns_query * +\fBdns_submit_txt\fB(\fIctx\fR, const char *\fIname\fR, enum dns_class \fIqcls\fR, + int \fIflags\fR, dns_query_txt_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_txt * +\fBdns_resolve_txt\fB(\fIctx\fR, const char *\fIname\fR, + enum dns_class \fIqcls\fR, int \fIflags\fR); +.fi +.PP +The \fBdns_rr_txt\fR structure holds a result of a TXT query, which is an +array of text records for a given domain name. Callback routine for TXT +queries expected to be of type \fBdns_query_txt_fn\fR, which expects pointer +to \fBdns_rr_txt\fR structure as query result instead of raw DNS packet. +The \fBdns_parse_txt\fR() is used to convert raw DNS reply packet into +\fBdns_rr_txt\fR structure (it is used internally and may be used directly too +with generic query interface). Routines \fBdns_submit_txt\fR() and +\fBdns_resolve_txt\fR() are used to perform IN MX queries in a type-safe +manner. The \fIname\fR parameter is the domain name in question, and +\fIflags\fR is query flags bitmask, with one bit, DNS_NOSRCH, of practical +interest (if the \fIname\fR is absolute, that is, it ends up with a dot, +DNS_NOSRCH flag will be set automatically). Note that each TXT string +is represented by \fBstruct\ dns_txt\fR, while zero-terminated (and the +len field of the structure does not include the terminator), may contain +embedded null characters -- content of TXT records is not interpreted +by the library in any way. + +.SS "SRV Queries" +.PP +.nf +struct \fBdns_srv\fR { /* single SRV record */ + int \fBpriority\fR; /* priority of the record */ + int \fBweight\fR; /* weight of the record */ + int \fBport\fR; /* the port number to connect to */ + char *\fBname\fR; /* target host name */ +}; +struct \fBdns_rr_srv\fR { /* SRV RRset */ + char *\fBdnssrv_qname\fR; /* original query name */ + char *\fBdnssrv_cname\fR; /* canonical name */ + unsigned \fBdnssrv_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnssrv_nrr\fR; /* number of text records in the set */ + struct dns_srv \fBdnssrv_srv\fR[]; /* array of SRV records */ +}; +typedef void + \fBdns_query_srv_fn\fR(\fIctx\fR, struct dns_rr_srv *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_srv\fB; +struct dns_query * +\fBdns_submit_srv\fB(\fIctx\fR, const char *\fIname\fR, const char *\fIservice\fR, const char *\fIprotocol\fR, + int \fIflags\fR, dns_query_txt_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_srv * +\fBdns_resolve_srv\fB(\fIctx\fR, const char *\fIname\fR, const char *\fIservice\fR, const char *\fIprotocol\fR, + int \fIflags\fR); +.fi +.PP +The \fBdns_rr_srv\fR structure holds a result of an IN SRV (rfc2782) query, +which is an array of servers (together with port numbers) which are performing +operations for a given \fIservice\fR using given \fIprotocol\fR on a target +domain \fIname\fR. Callback routine for IN SRV queries expected to be of type +\fBdns_query_srv_fn\fR, which expects pointer to \fBdns_rr_srv\fR structure as +query result instead of raw DNS packet. The \fBdns_parse_srv\fR() is used to +convert raw DNS reply packet into \fBdns_rr_srv\fR structure (it is used +internally and may be used directly too with generic query interface). +Routines \fBdns_submit_srv\fR() and \fBdns_resolve_srv\fR() are used to +perform IN SRV queries in a type-safe manner. The \fIname\fR parameter +is the domain name in question, \fIservice\fR and \fRprotocl\fR specifies the +service and the protocol in question (the library will construct query DN +according to rfc2782 rules) and may be NULL (in this case the library +assumes \fIname\fR parameter holds the complete SRV query), and +\fIflags\fR is query flags bitmask, with one bit, DNS_NOSRCH, of practical +interest (if the \fIname\fR is absolute, that is, it ends up with a dot, +DNS_NOSRCH flag will be set automatically). + +.SS "NAPTR Queries" +.PP +.nf +struct \fBdns_naptr\fR { /* single NAPTR record */ + int \fBorder\fR; /* record order */ + int \fBpreference\fR; /* preference of this record */ + char *\fBflags\fR; /* application-specific flags */ + char *\fBservices\fR; /* service parameters */ + char *\fBregexp\fR; /* substitutional regular expression */ + char *\fBreplacement\fR; /* replacement string */ +}; +struct \fBdns_rr_naptr\fR { /* NAPTR RRset */ + char *\fBdnsnaptr_qname\fR; /* original query name */ + char *\fBdnsnaptr_cname\fR; /* canonical name */ + unsigned \fBdnsnaptr_ttl\fR; /* Time-To-Live (TTL) value */ + int \fBdnsnaptr_nrr\fR; /* number of text records in the set */ + struct dns_naptr \fBdnsnaptr_naptr\fR[]; /* array of NAPTR records */ +}; +typedef void + \fBdns_query_naptr_fn\fR(\fIctx\fR, struct dns_rr_naptr *\fIresult\fR, \fIdata\fR) +dns_parse_fn \fBdns_parse_naptr\fB; +struct dns_query * +\fBdns_submit_naptr\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR, + dns_query_txt_fn *\fIcbck\fR, \fIdata\fR); +struct dns_rr_naptr * +\fBdns_resolve_naptr\fB(\fIctx\fR, const char *\fIname\fR, int \fIflags\fR); +.fi +.PP +The \fBdns_rr_naptr\fR structure holds a result of an IN NAPTR (rfc3403) query. +Callback routine for IN NAPTR queries expected to be of type +\fBdns_query_naptr_fn\fR, expects pointer to \fBdns_rr_naptr\fR +structure as query result instead of raw DNS packet. +The \fBdns_parse_naptr\fR() is used to convert raw DNS reply packet into +\fBdns_rr_naptr\fR structure (it is used +internally and may be used directly too with generic query interface). +Routines \fBdns_submit_naptr\fR() and \fBdns_resolve_naptr\fR() are used to +perform IN NAPTR queries in a type-safe manner. The \fIname\fR parameter +is the domain name in question, and \fIflags\fR is query flags bitmask, +with one bit, DNS_NOSRCH, of practical interest (if the \fIname\fR is +absolute, that is, it ends up with a dot, DNS_NOSRCH flag will be set +automatically). + +.SS "DNSBL Interface" +.PP +A DNS-based blocklists, or a DNSBLs, are in wide use nowadays, especially +to protect mailservers from spammers. The library provides DNSBL interface, +a set of routines to perform queries against DNSBLs. Routines accepts an +IP address (IPv4 and IPv6 are both supported) and a base DNSBL zone as +query parameters, and returns either \fBdns_rr_a4\fR or \fBdns_rr_txt\fR +structure. Note that IPv6 interface return IPv4 RRset. +.PP +.nf +struct dns_query * +\fBdns_submit_a4dnsbl\fR(\fIctx\fR, + const struct in_addr *\fIaddr\fR, const char *\fIdnsbl\fR, + dns_query_a4_fn *\fIcbck\fR, void *\fIdata\fR); +struct dns_query * +\fBdns_submit_a4dnsbl_txt\fR(\fIctx\fR, + const struct in_addr *\fIaddr\fR, const char *\fIdnsbl\fR, + dns_query_txt_fn *\fIcbck\fR, void *\fIdata\fR); +struct dns_query * +\fBdns_submit_a6dnsbl\fR(\fIctx\fR, + const struct in6_addr *\fIaddr\fR, const char *\fIdnsbl\fR, + dns_query_a4_fn *\fIcbck\fR, void *\fIdata\fR); +struct dns_query * +\fBdns_submit_a6dnsbl_txt\fR(\fIctx\fR, + const struct in6_addr *\fIaddr\fR, const char *\fIdnsbl\fR, + dns_query_txt_fn *\fIcbck\fR, void *\fIdata\fR); +struct dns_rr_a4 *\fBdns_resolve_a4dnsbl\fR(\fIctx\fR, + const struct in_addr *\fIaddr\fR, const char *\fIdnsbl\fR) +struct dns_rr_txt *\fBdns_resolve_a4dnsbl_txt\fR(\fIctx\fR, + const struct in_addr *\fIaddr\fR, const char *\fIdnsbl\fR) +struct dns_rr_a4 *\fBdns_resolve_a6dnsbl\fR(\fIctx\fR, + const struct in6_addr *\fIaddr\fR, const char *\fIdnsbl\fR) +struct dns_rr_txt *\fBdns_resolve_a6dnsbl_txt\fR(\fIctx\fR, + const struct in6_addr *\fIaddr\fR, const char *\fIdnsbl\fR) +.fi +Perform (submit or resolve) a DNSBL query for the given \fIdnsbl\fR +domain and an IP \fIaddr\fR in question, requesting either A or TXT +records. + +.SS "RHSBL Interface" +.PP +RHSBL is similar to DNSBL, but instead of an IP address, the +parameter is a domain name. +.PP +.nf +struct dns_query * +\fBdns_submit_rhsbl\fR(\fIctx\fR, const char *\fIname\fR, const char *\fIrhsbl\fR, + dns_query_a4_fn *\fIcbck\fR, void *\fIdata\fR); +struct dns_query * +\fBdns_submit_rhsbl_txt\fR(\fIctx\fR, const char *\fIname\fR, const char *\fIrhsbl\fR, + dns_query_txt_fn *\fIcbck\fR, void *\fIdata\fR); +struct dns_rr_a4 * +\fBdns_resolve_rhsbl\fR(\fIctx\fR, const char *\fIname\fR, const char *\fIrhsbl\fR); +struct dns_rr_txt * +\fBdns_resolve_rhsbl_txt\fR(\fIctx\fR, const char *\fIname\fR, const char *\fIrhsbl\fR); +.fi +Perform (submit or resolve) a RHSBL query for the given \fIrhsbl\fR +domain and \fIname\fR in question, requesting either A or TXT records. + + +.SH "LOW-LEVEL INTERFACE" + +.SS "Domain Names (DNs)" + +.PP +A DN is a series of domain name labels each starts with length byte, +followed by empty label (label with zero length). The following +routines to work with DNs are provided. + +.PP +.nf +unsigned \fBdns_dnlen\fR(const unsigned char *\fIdn\fR) +.fi +.RS +return length of the domain name \fIdn\fR, including the terminating label. +.RE + +.PP +.nf +unsigned \fBdns_dnlabels\fR(const unsigned char *\fIdn\fR) +.fi +.RS +return number of non-zero labels in domain name \fIdn\fR. +.RE + +.PP +.nf +unsigned \fBdns_dnequal\fR(\fIdn1\fR, \fIdn2\fR) + const unsigned char *\fIdn1\fR, *\fIdn2\fR; +.fi +.RS +test whenever the two domain names, \fIdn1\fR and \fIdn2\fR, are +equal (case-insensitive). Return domain name length if equal +or 0 if not. +.RE + +.PP +.nf +unsigned \fBdns_dntodn\fR(\fIsdn\fR, \fIddn\fR, \fIdnsiz\fR) + const unsigned char *\fIsdn\fR; + unsigned char *\fIddn\fR; + unsigned \fIdnsiz\fR; +.fi +.RS +copies the source domain name \fIsdn\fR to destination buffer \fIddn\fR +of size \fIdnsiz\fR. Return domain name length or 0 if \fIddn\fR is +too small. +.RE + +.PP +.nf +int \fBdns_ptodn\fR(\fIname\fR, \fInamelen\fR, \fIdn\fR, \fIdnsiz\fR, \fIisabs\fR) +int \fBdns_sptodn\fR(\fIname\fR, \fIdn\fR, \fIdnsiz\fR) + const char *\fIname\fR; unsigned \fInamelen\fR; + unsigned char *\fIdn\fR; unsigned \fIdnsiz\fR; + int *\fIisabs\fR; +.fi +.RS +convert asciiz name \fIname\fR of length \fInamelen\fR to DN format, +placing result into buffer \fIdn\fR of size \fIdnsiz\fR. Return +length of the DN if successeful, 0 if the \fIdn\fR buffer supplied is +too small, or negative value if \fIname\fR is invalid. If \fIisabs\fR +is non-NULL and conversion was successeful, *\fIisabs\fR will be set to +either 1 or 0 depending whenever \fIname\fR was absolute (i.e. ending with +a dot) or not. Name length, \fInamelength\fR, may be zero, in which case +strlen(\fIname\fR) will be used. Second form, \fBdns_sptodn\fR(), is a +simplified form of \fBdns_ptodn\fR(), equivalent to +.br +.nf +\fBdns_ptodn\fR(\fIname\fR, 0, \fIdn\fR, \fIdnlen\fR, 0). +.fi +.RE + +.PP +.nf +extern const unsigned char \fBdns_inaddr_arpa_dn\fR[] +int \fBdns_a4todn\fR(const struct in_addr *\fIaddr\fR, const unsigned char *\fItdn\fR, + unsigned char *\fIdn\fR, unsigned \fIdnsiz\fR) +int \fBdns_a4ptodn\fR(const struct in_addr *\fIaddr\fR, const char *\fItname\fR, + unsigned char *\fIdn\fR, unsigned \fIdnsiz\fR) +extern const unsigned char \fBdns_ip6_arpa_dn\fR[] +int \fBdns_a6todn\fR(const struct in6_addr *\fIaddr\fR, const unsigned char *\fItdn\fR, + unsigned char *\fIdn\fR, unsigned \fIdnsiz\fR) +int \fBdns_a6ptodn\fR(const struct in6_addr *\fIaddr\fR, const char *\fItname\fR, + unsigned char *\fIdn\fR, unsigned \fIdnsiz\fR) +.fi +.RS +several variants of routines to convert IPv4 and IPv6 address \fIaddr\fR +into reverseDNS-like domain name in DN format, storing result in \fIdn\fR +of size \fIdnsiz\fR. \fItdn\fR (or \fItname\fR) is the base zone name, +like in-addr.arpa for IPv4 or in6.arpa for IPv6. If \fItdn\fR (or \fItname\fR) +is NULL, \fBdns_inaddr_arpa_dn\fR (or \fBdns_ip6_arpa_dn\fR) will be used. +The routines may be used to construct a DN for a DNSBL lookup for example. +All routines return length of the resulting DN on success, -1 if resulting +DN is invalid, or 0 if the \fIdn\fR buffer (\fIdnsiz\fR) is too small. +To hold standard rDNS DN, a buffer of size \fBDNS_A4RSIZE\fR (30 bytes) for +IPv4 address, or \fBDNS_A6RSIZE\fR (74 bytes) for IPv6 address, is sufficient. +.RE + +.PP +.nf +int \fBdns_dntop\fR(\fIdn\fR, \fIname\fR, \fInamesiz\fR) + const unsigned char *\fIdn\fR; + const char *\fIname\fR; unsigned \fInamesiz\fR; +.fi +.RS +convert domain name \fIdn\fR in DN format to asciiz string, placing result +into \fIname\fR buffer of size \fInamesiz\fR. Maximum length of asciiz +representation of domain name is \fBDNS_MAXNAME\fR (1024) bytes. Root +domain is represented as empty string. Return length of the resulting name +(including terminating character, i.e. strlen(name)+1) on success, 0 if the +\fIname\fR buffer is too small, or negative value if \fIdn\fR is invalid +(last case should never happen since all routines in this library which +produce domain names ensure the DNs generated are valid). +.RE + +.PP +.nf +const char *\fBdns_dntosp\fR(const unsigned char *\fIdn\fR) +.fi +.RS +convert domain name \fIdn\fR in DN format to asciiz string using static +buffer. Return the resulting asciiz string on success or NULL on failure. +Note since this routine uses static buffer, it is not thread-safe. +.RE + +.PP +.nf +unsigned \fBdns_dntop_size\fR(const unsigned char *\fIdn\fR) +.fi +.RS +return the buffer size needed to convert the \fIdn\fR domain name +in DN format to asciiz string, for \fBdns_dntop\fR(). The routine +return either the size of buffer required, including the trailing +zero byte, or 0 if \fIdn\fR is invalid. +.RE + +.SS "Working with DNS Packets" + +.PP +The following routines are provided to encode and decode DNS on-wire +packets. This is low-level interface. + +.PP +DNS response codes (returned by \fBdns_rcode\fR() routine) are +defined as constants prefixed with \fBDNS_R_\fR. See dns.h +header file for the complete list. In particular, constants +\fBDNS_R_NOERROR\fR (0), \fBDNS_R_SERVFAIL\fR, \fBDNS_R_NXDOMAIN\fR +may be of interest to an application. + +.PP +.nf +unsigned \fBdns_get16\fR(const unsigned char *\fIp\fR) +unsigned \fBdns_get32\fR(const unsigned char *\fIp\fR) +.fi +.RS +helper routines, convert 16-bit or 32-bit integer in on-wire +format pointed to by \fIp\fR to unsigned. +.RE + +.PP +.nf +unsigned char *\fBdns_put16\fR(unsigned char *\fId\fR, unsigned \fIn\fR) +unsigned char *\fBdns_put32\fR(unsigned char *\fId\fR, unsigned \fIn\fR) +.fi +.RS +helper routine, convert unsigned 16-bit or 32-bit integer \fIn\fR to +on-wire format to buffer pointed to by \fId\fR, return \fId\fR+2 or +\fId\fR+4. +.RE + +.PP +.nf +\fBDNS_HSIZE\fR (12) +.fi +.RS +defines size of DNS header. Data section +in the DNS packet immediately follows the header. In the header, +there are query identifier (id), various flags and codes, +and number of resource records in various data sections. +See dns.h header file for complete list of DNS header definitions. +.RE + +.PP +.nf +unsigned \fBdns_qid\fR(const unsigned char *\fIpkt\fR) +int \fBdns_rd\fR(const unsigned char *\fIpkt\fR) +int \fBdns_tc\fR(const unsigned char *\fIpkt\fR) +int \fBdns_aa\fR(const unsigned char *\fIpkt\fR) +int \fBdns_qr\fR(const unsigned char *\fIpkt\fR) +int \fBdns_ra\fR(const unsigned char *\fIpkt\fR) +unsigned \fBdns_opcode\fR(const unsigned char *\fIpkt\fR) +unsigned \fBdns_rcode\fR(const unsigned char *\fIpkt\fR) +unsigned \fBdns_numqd\fR(const unsigned char *\fIpkt\fR) +unsigned \fBdns_numan\fR(const unsigned char *\fIpkt\fR) +unsigned \fBdns_numns\fR(const unsigned char *\fIpkt\fR) +unsigned \fBdns_numar\fR(const unsigned char *\fIpkt\fR) +const unsigned char *\fBdns_payload\fR(const unsigned char *\fIpkt\fR) +.fi +.RS +return various parts from the DNS packet header \fIpkt\fR: +query identifier (qid), +recursion desired (rd) flag, +truncation occured (tc) flag, +authoritative answer (aa) flag, +query response (qr) flag, +recursion available (ra) flag, +operation code (opcode), +result code (rcode), +number of entries in question section (numqd), +number of answers (numan), +number of authority records (numns), +number of additional records (numar), +and the pointer to the packet data (payload). +.RE + +.PP +.nf +int \fBdns_getdn\fR(\fIpkt\fR, \fIcurp\fR, \fIpkte\fR, \fIdn\fR, \fIdnsiz\fR) +const unsigned char *\fBdns_skipdn\fR(\fIcur\fR, \fIpkte\fR) + const unsigned char *\fIpkt\fR, *\fIpkte\fR, **\fIcurp\fR, *\fIcur\fR; + unsigned char *\fIdn\fR; unsigned \fIdnsiz\fR; +.fi +.RS +\fBdns_getdn\fR() extract DN from DNS packet \fIpkt\fR which ends before +\fIpkte\fR starting at position *\fIcurp\fR into buffer pointed to by +\fIdn\fR of size \fIdnsiz\fR. Upon successeful completion, *\fIcurp\fR +will point to the next byte in the packet after the extracted domain name. +It return positive number (length of the DN if \fIdn\fR) upon successeful +completion, negative value on error (when the packet contains invalid data), +or zero if the \fIdnsiz\fR is too small (maximum length of a domain name is +\fBDNS_MAXDN\fR). \fBdns_skipdn\fR() return pointer to the next byte in +DNS packet which ends up before \fIpkte\fR after a domain name which starts +at the \fIcur\fP byte, or NULL if the packet is invalid. \fBdns_skipdn\fR() +is more or less equivalent to what \fBdns_getdn\fR() does, except it does not +actually extract the domain name in question, and uses simpler interface. +.RE + +.PP +.nf +struct \fBdns_rr\fR { + unsigned char \fBdnsrr_dn\fR[DNS_MAXDN]; /* the RR DN name */ + enum dns_class \fBdnsrr_cls\fR; /* class of the RR */ + enum dns_type \fBdnsrr_typ\fR; /* type of the RR */ + unsigned \fBdnsrr_ttl\fR; /* TTL value */ + unsigned \fBdnsrr_dsz\fR; /* size of data in bytes */ + const unsigned char *\fBdnsrr_dptr\fR; /* pointer to the first data byte */ + const unsigned char *\fBdnsrr_dend\fR; /* next byte after RR */ +}; +.fi +.RS +The \fBdns_rr\fR structure is used to hold information about +single DNS Resource Record (RR) in an easy to use form. +.RE + +.PP +.nf +struct \fBdns_parse\fR { + const unsigned char *\fBdnsp_pkt\fR; /* pointer to the packet being parsed */ + const unsigned char *\fBdnsp_end\fR; /* end of the packet pointer */ + const unsigned char *\fBdnsp_cur\fR; /* current packet positionn */ + const unsigned char *\fBdnsp_ans\fR; /* pointer to the answer section */ + int \fBdnsp_rrl\fR; /* number of RRs left */ + int \fBdnsp_nrr\fR; /* number of relevant RRs seen so far */ + unsigned \fBdnsp_ttl\fR; /* TTL value so far */ + const unsigned char *\fBdnsp_qdn\fR; /* the domain of interest or NULL */ + enum dns_class \fBdnsp_qcls\fR; /* class of interest or 0 for any */ + enum dns_type \fBdnsp_qtyp\fR; /* type of interest or 0 for any */ + unsigned char \fBdnsp_dnbuf\fR[DNS_MAXDN]; /* domain name buffer */ +}; +.fi +.RS +The \fBdns_parse\fR structure is used to parse DNS reply packet. +It holds information about the packet being parsed (dnsp_pkt, dnsp_end and +dnsp_cur fields), number of RRs in the current section left to do, and +the information about specific RR which we're looking for (dnsp_qdn, +dnsp_qcls and dnsp_qtyp fields). +.RE + +.PP +.nf +int \fBdns_initparse\fR(struct dns_parse *\fIp\fR, + const unsigned char *\fIqdn\fR, + const unsigned char *\fIpkt\fR, + const unsigned char *\fIcur\fR, + const unsigned char *\fIend\fR) +.fi +.RS +initializes the RR parsing structure \fIp\fR. Arguments \fIpkt\fR, \fIcur\fR +and \fIend\fR should describe the received packet: \fIpkt\fR is the start of +the packet, \fIend\fR points to the next byte after the end of the packet, +and \fIcur\fR points past the query DN in query section (to query class+type +information). And \fIqdn\fR points to the query DN. This is the arguments +passed to \fBdns_parse_fn\fR() routine. \fBdns_initparse\fR() initializes +\fBdnsp_pkt\fR, \fBdnsp_end\fR and \fBdnsp_qdn\fR fields to the corresponding +arguments, extracts and initializes \fBdnsp_qcls\fR and \fBdnsp_qtyp\fR +fields to the values found at \fIcur\fR pointer, initializes +\fBdnsp_cur\fR and \fBdnsp_ans\fR fields to be \fIcur\fR+4 (to the start of +answer section), and initializes \fBdnsp_rrl\fR field to be number of entries +in answer section. \fBdnsp_ttl\fR will be set to max TTL value, 0xffffffff, +and \fBdnsp_nrr\fR to 0. +.RE + +.PP +.nf +int \fBdns_nextrr\fR(struct dns_parse *\fIp\fR, struct dns_rr *\fIrr\fR); +.fi +.RS +searches for next RR in the packet based on the criteria provided in +the \fIp\fR structure, filling in the \fIrr\fR structure and +advancing \fIp\fR->\fBdnsp_cur\fR to the next RR in the packet. +RR selection is based on dnsp_qdn, dnsp_qcls and dnsp_qtyp fields in +the dns_parse structure. Any (or all) of the 3 fields may be 0, +which means any actual value from the packet is acceptable. In case +the field isn't 0 (or NULL for dnsp_qdn), only RRs with corresponding +characteristics are acceptable. Additionally, when dnsp_qdn is non-NULL, +\fBdns_nextrr\fR() performs automatic CNAME expansion. +Routine will return positive value on success, 0 in case it reached the end +of current section in the packet (\fIp\fR->\fBdnsp_rrl\fR is zero), or +negative value if next RR can not be decoded (packet format is invalid). +The routine updates \fIp\fR->\fBdnsp_qdn\fR automatically when this +field is non-NULL and it encounters appropriate CNAME RRs (saving CNAME +target in \fIp\fR->\fBdnsp_dnbuf\fR), so after end of the process, +\fIp\fR->\fBdnsp_qdn\fR will point to canonical name of the domain +in question. The routine updates \fIp\fR->\fBdnsp_ttl\fR value to +be the minimum TTL of all RRs found. +.RE + +.PP +.nf +void \fBdns_rewind\fR(struct dns_parse *\fIp\fR, const unsigned char *\fIqdn\fR) +.fi +.RS +this routine "rewinds" the packet parse state structure to be at the +same state as after a call to \fBdns_initparse\fR(), i.e. reposition +the parse structure \fIp\fR to the start of answer section and +initialize \fIp\fR->\fBdnsp_rrl\fR to the number of entries in +answer section. +.RE + +.PP +.nf +int \fBdns_stdrr_size\fR(const struct dns_parse *\fIp\fR); +.fi +.RS +return size to hold standard RRset structure information, as shown +in \fBdns_rr_null\fR structure (for the query and canonical +names). Used to calculate amount of memory to allocate for common +part of type-specific RR structures in parsing routines. +.RE + +.PP +.nf +void *\fBdns_stdrr_finish\fR(struct dns_rr_null *\fIret\fR, char *\fIcp\fR, + const struct dns_parse *\fIp\fR); +.fi +.RS +initializes standard RRset fields in \fIret\fR structure using buffer +pointed to by \fIcp\fR, which should have at least as many bytes +as \fBdns_stdrr_size\fR(\fIp\fR) returned. Used to finalize common +part of type-specific RR structures in parsing routines. +.RE + +.PP +See library source for usage examples of all the above low-level routines, +especially source of the parsing routines. + +.SH AUTHOR +.PP +The \fBudns\fR library has been written by Michael Tokarev, mjt@corpit.ru. diff --git a/libs/udns/udns.h b/libs/udns/udns.h new file mode 100644 index 0000000000..7e89b853c8 --- /dev/null +++ b/libs/udns/udns.h @@ -0,0 +1,736 @@ +/* $Id: udns.h,v 1.41 2006/11/29 01:20:30 mjt Exp $ + header file for the UDNS library. + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#ifndef UDNS_VERSION /* include guard */ + +#define UDNS_VERSION "0.0.9pre" + +#ifdef WIN32 +# ifdef UDNS_DYNAMIC_LIBRARY +# ifdef DNS_LIBRARY_BUILD +# define UDNS_API __declspec(dllexport) +# define UDNS_DATA_API __declspec(dllexport) +# else +# define UDNS_API __declspec(dllimport) +# define UDNS_DATA_API __declspec(dllimport) +# endif +# endif +#endif + +#ifndef UDNS_API +# define UDNS_API +#endif +#ifndef UDNS_DATA_API +# define UDNS_DATA_API +#endif + +#include /* for time_t */ + +#ifdef __cplusplus +extern "C" { +#endif + +/* forward declarations if sockets stuff isn't #include'd */ +struct in_addr; +struct in6_addr; +struct sockaddr; + +/**************************************************************************/ +/**************** Common definitions **************************************/ + +UDNS_API const char * +dns_version(void); + +struct dns_ctx; +struct dns_query; + +/* shorthand for [const] unsigned char */ +typedef unsigned char dnsc_t; +typedef const unsigned char dnscc_t; + +#define DNS_MAXDN 255 /* max DN length */ +#define DNS_MAXLABEL 63 /* max DN label length */ +#define DNS_MAXNAME 1024 /* max asciiz domain name length */ +#define DNS_HSIZE 12 /* DNS packet header size */ +#define DNS_PORT 53 /* default domain port */ +#define DNS_MAXSERV 6 /* max servers to consult */ +#define DNS_MAXSRCH 5 /* max searchlist entries */ +#define DNS_MAXPACKET 512 /* max traditional-DNS UDP packet size */ +#define DNS_EDNS0PACKET 4096 /* EDNS0 packet size to use */ + +enum dns_class { /* DNS RR Classes */ + DNS_C_INVALID = 0, /* invalid class */ + DNS_C_IN = 1, /* Internet */ + DNS_C_CH = 3, /* CHAOS */ + DNS_C_HS = 4, /* HESIOD */ + DNS_C_ANY = 255 /* wildcard */ +}; + +enum dns_type { /* DNS RR Types */ + DNS_T_INVALID = 0, /* Cookie. */ + DNS_T_A = 1, /* Host address. */ + DNS_T_NS = 2, /* Authoritative server. */ + DNS_T_MD = 3, /* Mail destination. */ + DNS_T_MF = 4, /* Mail forwarder. */ + DNS_T_CNAME = 5, /* Canonical name. */ + DNS_T_SOA = 6, /* Start of authority zone. */ + DNS_T_MB = 7, /* Mailbox domain name. */ + DNS_T_MG = 8, /* Mail group member. */ + DNS_T_MR = 9, /* Mail rename name. */ + DNS_T_NULL = 10, /* Null resource record. */ + DNS_T_WKS = 11, /* Well known service. */ + DNS_T_PTR = 12, /* Domain name pointer. */ + DNS_T_HINFO = 13, /* Host information. */ + DNS_T_MINFO = 14, /* Mailbox information. */ + DNS_T_MX = 15, /* Mail routing information. */ + DNS_T_TXT = 16, /* Text strings. */ + DNS_T_RP = 17, /* Responsible person. */ + DNS_T_AFSDB = 18, /* AFS cell database. */ + DNS_T_X25 = 19, /* X_25 calling address. */ + DNS_T_ISDN = 20, /* ISDN calling address. */ + DNS_T_RT = 21, /* Router. */ + DNS_T_NSAP = 22, /* NSAP address. */ + DNS_T_NSAP_PTR = 23, /* Reverse NSAP lookup (deprecated). */ + DNS_T_SIG = 24, /* Security signature. */ + DNS_T_KEY = 25, /* Security key. */ + DNS_T_PX = 26, /* X.400 mail mapping. */ + DNS_T_GPOS = 27, /* Geographical position (withdrawn). */ + DNS_T_AAAA = 28, /* Ip6 Address. */ + DNS_T_LOC = 29, /* Location Information. */ + DNS_T_NXT = 30, /* Next domain (security). */ + DNS_T_EID = 31, /* Endpoint identifier. */ + DNS_T_NIMLOC = 32, /* Nimrod Locator. */ + DNS_T_SRV = 33, /* Server Selection. */ + DNS_T_ATMA = 34, /* ATM Address */ + DNS_T_NAPTR = 35, /* Naming Authority PoinTeR */ + DNS_T_KX = 36, /* Key Exchange */ + DNS_T_CERT = 37, /* Certification record */ + DNS_T_A6 = 38, /* IPv6 address (deprecates AAAA) */ + DNS_T_DNAME = 39, /* Non-terminal DNAME (for IPv6) */ + DNS_T_SINK = 40, /* Kitchen sink (experimentatl) */ + DNS_T_OPT = 41, /* EDNS0 option (meta-RR) */ + DNS_T_DS = 43, /* DNSSEC */ + DNS_T_NSEC = 47, /* DNSSEC */ + DNS_T_TSIG = 250, /* Transaction signature. */ + DNS_T_IXFR = 251, /* Incremental zone transfer. */ + DNS_T_AXFR = 252, /* Transfer zone of authority. */ + DNS_T_MAILB = 253, /* Transfer mailbox records. */ + DNS_T_MAILA = 254, /* Transfer mail agent records. */ + DNS_T_ANY = 255, /* Wildcard match. */ + DNS_T_ZXFR = 256, /* BIND-specific, nonstandard. */ + DNS_T_MAX = 65536 +}; + +/**************************************************************************/ +/**************** Domain Names (DNs) **************************************/ + +/* return length of the DN */ +UDNS_API unsigned +dns_dnlen(dnscc_t *dn); + +/* return #of labels in a DN */ +UDNS_API unsigned +dns_dnlabels(dnscc_t *dn); + +/* lower- and uppercase single DN char */ +#define DNS_DNLC(c) ((c) >= 'A' && (c) <= 'Z' ? (c) - 'A' + 'a' : (c)) +#define DNS_DNUC(c) ((c) >= 'a' && (c) <= 'z' ? (c) - 'a' + 'A' : (c)) + +/* compare the DNs, return dnlen of equal or 0 if not */ +UDNS_API unsigned +dns_dnequal(dnscc_t *dn1, dnscc_t *dn2); + +/* copy one DN to another, size checking */ +UDNS_API unsigned +dns_dntodn(dnscc_t *sdn, dnsc_t *ddn, unsigned ddnsiz); + +/* convert asciiz string of length namelen (0 to use strlen) to DN */ +UDNS_API int +dns_ptodn(const char *name, unsigned namelen, + dnsc_t *dn, unsigned dnsiz, int *isabs); + +/* simpler form of dns_ptodn() */ +#define dns_sptodn(name,dn,dnsiz) dns_ptodn((name),0,(dn),(dnsiz),0) + +UDNS_DATA_API extern dnscc_t dns_inaddr_arpa_dn[14]; +#define DNS_A4RSIZE 30 +UDNS_API int +dns_a4todn(const struct in_addr *addr, dnscc_t *tdn, + dnsc_t *dn, unsigned dnsiz); +UDNS_API int +dns_a4ptodn(const struct in_addr *addr, const char *tname, + dnsc_t *dn, unsigned dnsiz); +UDNS_API dnsc_t * +dns_a4todn_(const struct in_addr *addr, dnsc_t *dn, dnsc_t *dne); + +UDNS_DATA_API extern dnscc_t dns_ip6_arpa_dn[10]; +#define DNS_A6RSIZE 74 +UDNS_API int +dns_a6todn(const struct in6_addr *addr, dnscc_t *tdn, + dnsc_t *dn, unsigned dnsiz); +UDNS_API int +dns_a6ptodn(const struct in6_addr *addr, const char *tname, + dnsc_t *dn, unsigned dnsiz); +UDNS_API dnsc_t * +dns_a6todn_(const struct in6_addr *addr, dnsc_t *dn, dnsc_t *dne); + +/* convert DN into asciiz string */ +UDNS_API int +dns_dntop(dnscc_t *dn, char *name, unsigned namesiz); + +/* convert DN into asciiz string, using static buffer (NOT thread-safe!) */ +UDNS_API const char * +dns_dntosp(dnscc_t *dn); + +/* return buffer size (incl. null byte) required for asciiz form of a DN */ +UDNS_API unsigned +dns_dntop_size(dnscc_t *dn); + +/**************************************************************************/ +/**************** DNS raw packet layout ***********************************/ + +enum dns_rcode { /* reply codes */ + DNS_R_NOERROR = 0, /* ok, no error */ + DNS_R_FORMERR = 1, /* format error */ + DNS_R_SERVFAIL = 2, /* server failed */ + DNS_R_NXDOMAIN = 3, /* domain does not exists */ + DNS_R_NOTIMPL = 4, /* not implemented */ + DNS_R_REFUSED = 5, /* query refused */ + /* these are for BIND_UPDATE */ + DNS_R_YXDOMAIN = 6, /* Name exists */ + DNS_R_YXRRSET = 7, /* RRset exists */ + DNS_R_NXRRSET = 8, /* RRset does not exist */ + DNS_R_NOTAUTH = 9, /* Not authoritative for zone */ + DNS_R_NOTZONE = 10, /* Zone of record different from zone section */ + /*ns_r_max = 11,*/ + /* The following are TSIG extended errors */ + DNS_R_BADSIG = 16, + DNS_R_BADKEY = 17, + DNS_R_BADTIME = 18 +}; + +static __inline unsigned dns_get16(dnscc_t *s) { + return ((unsigned)s[0]<<8) | s[1]; +} +static __inline unsigned dns_get32(dnscc_t *s) { + return ((unsigned)s[0]<<24) | ((unsigned)s[1]<<16) + | ((unsigned)s[2]<<8) | s[3]; +} +static __inline dnsc_t *dns_put16(dnsc_t *d, unsigned n) { + *d++ = (n >> 8) & 255; *d++ = n & 255; return d; +} +static __inline dnsc_t *dns_put32(dnsc_t *d, unsigned n) { + *d++ = (n >> 24) & 255; *d++ = (n >> 16) & 255; + *d++ = (n >> 8) & 255; *d++ = n & 255; + return d; +} + +/* DNS Header layout */ +enum { + /* bytes 0:1 - query ID */ + DNS_H_QID1 = 0, + DNS_H_QID2 = 1, + DNS_H_QID = DNS_H_QID1, +#define dns_qid(pkt) dns_get16((pkt)+DNS_H_QID) + /* byte 2: flags1 */ + DNS_H_F1 = 2, + DNS_HF1_QR = 0x80, /* query response flag */ +#define dns_qr(pkt) ((pkt)[DNS_H_F1]&DNS_HF1_QR) + DNS_HF1_OPCODE = 0x78, /* opcode, 0 = query */ +#define dns_opcode(pkt) (((pkt)[DNS_H_F1]&DNS_HF1_OPCODE)>>3) + DNS_HF1_AA = 0x04, /* auth answer */ +#define dns_aa(pkt) ((pkt)[DNS_H_F1]&DNS_HF1_AA) + DNS_HF1_TC = 0x02, /* truncation flag */ +#define dns_tc(pkt) ((pkt)[DNS_H_F1]&DNS_HF1_TC) + DNS_HF1_RD = 0x01, /* recursion desired (may be set in query) */ +#define dns_rd(pkt) ((pkt)[DNS_H_F1]&DNS_HF1_RD) + /* byte 3: flags2 */ + DNS_H_F2 = 3, + DNS_HF2_RA = 0x80, /* recursion available */ +#define dns_ra(pkt) ((pkt)[DNS_H_F2]&DNS_HF2_RA) + DNS_HF2_Z = 0x70, /* reserved */ + DNS_HF2_RCODE = 0x0f, /* response code, DNS_R_XXX above */ +#define dns_rcode(pkt) ((pkt)[DNS_H_F2]&DNS_HF2_RCODE) + /* bytes 4:5: qdcount, numqueries */ + DNS_H_QDCNT1 = 4, + DNS_H_QDCNT2 = 5, + DNS_H_QDCNT = DNS_H_QDCNT1, +#define dns_numqd(pkt) dns_get16((pkt)+4) + /* bytes 6:7: ancount, numanswers */ + DNS_H_ANCNT1 = 6, + DNS_H_ANCNT2 = 7, + DNS_H_ANCNT = DNS_H_ANCNT1, +#define dns_numan(pkt) dns_get16((pkt)+6) + /* bytes 8:9: nscount, numauthority */ + DNS_H_NSCNT1 = 8, + DNS_H_NSCNT2 = 9, + DNS_H_NSCNT = DNS_H_NSCNT1, +#define dns_numns(pkt) dns_get16((pkt)+8) + /* bytes 10:11: arcount, numadditional */ + DNS_H_ARCNT1 = 10, + DNS_H_ARCNT2 = 11, + DNS_H_ARCNT = DNS_H_ARCNT1, +#define dns_numar(pkt) dns_get16((pkt)+10) +#define dns_payload(pkt) ((pkt)+DNS_HSIZE) +}; + +/* packet buffer: start at pkt, end before pkte, current pos *curp. + * extract a DN and set *curp to the next byte after DN in packet. + * return -1 on error, 0 if dnsiz is too small, or dnlen on ok. + */ +UDNS_API int +dns_getdn(dnscc_t *pkt, dnscc_t **curp, dnscc_t *end, + dnsc_t *dn, unsigned dnsiz); + +/* skip the DN at position cur in packet ending before pkte, + * return pointer to the next byte after the DN or NULL on error */ +UDNS_API dnscc_t * +dns_skipdn(dnscc_t *end, dnscc_t *cur); + +struct dns_rr { /* DNS Resource Record */ + dnsc_t dnsrr_dn[DNS_MAXDN]; /* the DN of the RR */ + enum dns_class dnsrr_cls; /* Class */ + enum dns_type dnsrr_typ; /* Type */ + unsigned dnsrr_ttl; /* Time-To-Live (TTL) */ + unsigned dnsrr_dsz; /* data size */ + dnscc_t *dnsrr_dptr; /* pointer to start of data */ + dnscc_t *dnsrr_dend; /* past end of data */ +}; + +struct dns_parse { /* RR/packet parsing state */ + dnscc_t *dnsp_pkt; /* start of the packet */ + dnscc_t *dnsp_end; /* end of the packet */ + dnscc_t *dnsp_cur; /* current packet position */ + dnscc_t *dnsp_ans; /* start of answer section */ + int dnsp_rrl; /* number of RRs left to go */ + int dnsp_nrr; /* RR count so far */ + unsigned dnsp_ttl; /* TTL value so far */ + dnscc_t *dnsp_qdn; /* the RR DN we're looking for */ + enum dns_class dnsp_qcls; /* RR class we're looking for or 0 */ + enum dns_type dnsp_qtyp; /* RR type we're looking for or 0 */ + dnsc_t dnsp_dnbuf[DNS_MAXDN]; /* domain buffer */ +}; + +/* initialize the parse structure */ +UDNS_API void +dns_initparse(struct dns_parse *p, dnscc_t *qdn, + dnscc_t *pkt, dnscc_t *cur, dnscc_t *end); + +/* search next RR, <0=error, 0=no more RRs, >0 = found. */ +UDNS_API int +dns_nextrr(struct dns_parse *p, struct dns_rr *rr); + +UDNS_API void +dns_rewind(struct dns_parse *p, dnscc_t *qdn); + + +/**************************************************************************/ +/**************** Resolver Context ****************************************/ + +/* default resolver context */ +UDNS_DATA_API extern struct dns_ctx dns_defctx; + +/* initialize default resolver context and open it if do_open is true. + * <0 on failure. */ +UDNS_API int +dns_init(int do_open); + +/* return new resolver context with the same settings as copy */ +UDNS_API struct dns_ctx * +dns_new(const struct dns_ctx *copy); + +/* free resolver context; all queries are dropped */ +UDNS_API void +dns_free(struct dns_ctx *ctx); + +/* add nameserver for a resolver context (or reset nslist if serv==NULL) */ +UDNS_API int +dns_add_serv(struct dns_ctx *ctx, const char *serv); + +/* add nameserver using struct sockaddr array (with ports etc) */ +UDNS_API int +dns_add_serv_s(struct dns_ctx *ctx, const struct sockaddr *sa); + +/* add search list element for a resolver context (or reset it if srch==NULL) */ +UDNS_API int +dns_add_srch(struct dns_ctx *ctx, const char *srch); + +/* set options for a resolver context */ +UDNS_API int +dns_set_opts(struct dns_ctx *ctx, const char *opts); + +enum dns_opt { /* options */ + DNS_OPT_FLAGS, /* flags, DNS_F_XXX */ + DNS_OPT_TIMEOUT, /* timeout in secounds */ + DNS_OPT_NTRIES, /* number of retries */ + DNS_OPT_NDOTS, /* ndots */ + DNS_OPT_UDPSIZE, /* EDNS0 UDP size */ + DNS_OPT_PORT, /* port to use */ +}; + +/* set or get (if val<0) an option */ +UDNS_API int +dns_set_opt(struct dns_ctx *ctx, enum dns_opt opt, int val); + +enum dns_flags { + DNS_NOSRCH = 0x00010000, /* do not perform search */ + DNS_NORD = 0x00020000, /* request no recursion */ + DNS_AAONLY = 0x00040000, /* set AA flag in queries */ + DNS_PASSALL = 0x00080000, /* pass all replies to application */ +}; + +/* set the debug function pointer */ +typedef void +(dns_dbgfn)(int code, const struct sockaddr *sa, unsigned salen, + dnscc_t *pkt, int plen, + const struct dns_query *q, void *data); +UDNS_API void +dns_set_dbgfn(struct dns_ctx *ctx, dns_dbgfn *dbgfn); + +/* open and return UDP socket */ +UDNS_API int +dns_open(struct dns_ctx *ctx); + +/* return UDP socket or -1 if not open */ +UDNS_API int +dns_sock(const struct dns_ctx *ctx); + +/* close the UDP socket */ +UDNS_API void +dns_close(struct dns_ctx *ctx); + +/* return number of requests queued */ +UDNS_API int +dns_active(const struct dns_ctx *ctx); + +/* return status of the last operation */ +UDNS_API int +dns_status(const struct dns_ctx *ctx); +UDNS_API void +dns_setstatus(struct dns_ctx *ctx, int status); + +/* handle I/O event on UDP socket */ +UDNS_API void +dns_ioevent(struct dns_ctx *ctx, time_t now); + +/* process any timeouts, return time in secounds to the + * next timeout (or -1 if none) but not greather than maxwait */ +UDNS_API int +dns_timeouts(struct dns_ctx *ctx, int maxwait, time_t now); + +/* define timer requesting routine to use */ +typedef void dns_utm_fn(struct dns_ctx *ctx, int timeout, void *data); +UDNS_API void +dns_set_tmcbck(struct dns_ctx *ctx, dns_utm_fn *fn, void *data); + +/**************************************************************************/ +/**************** Making Queries ******************************************/ + +/* query callback routine */ +typedef void dns_query_fn(struct dns_ctx *ctx, void *result, void *data); + +/* query parse routine: raw DNS => application structure */ +typedef int +dns_parse_fn(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **res); + +enum dns_status { + DNS_E_NOERROR = 0, /* ok, not an error */ + DNS_E_TEMPFAIL = -1, /* timeout, SERVFAIL or similar */ + DNS_E_PROTOCOL = -2, /* got garbled reply */ + DNS_E_NXDOMAIN = -3, /* domain does not exists */ + DNS_E_NODATA = -4, /* domain exists but no data of reqd type */ + DNS_E_NOMEM = -5, /* out of memory while processing */ + DNS_E_BADQUERY = -6 /* the query is malformed */ +}; + +/* submit generic DN query */ +UDNS_API struct dns_query * +dns_submit_dn(struct dns_ctx *ctx, + dnscc_t *dn, int qcls, int qtyp, int flags, + dns_parse_fn *parse, dns_query_fn *cbck, void *data); +/* submit generic name query */ +UDNS_API struct dns_query * +dns_submit_p(struct dns_ctx *ctx, + const char *name, int qcls, int qtyp, int flags, + dns_parse_fn *parse, dns_query_fn *cbck, void *data); + +/* cancel the given async query in progress */ +UDNS_API int +dns_cancel(struct dns_ctx *ctx, struct dns_query *q); + +/* resolve a generic query, return the answer */ +UDNS_API void * +dns_resolve_dn(struct dns_ctx *ctx, + dnscc_t *qdn, int qcls, int qtyp, int flags, + dns_parse_fn *parse); +UDNS_API void * +dns_resolve_p(struct dns_ctx *ctx, + const char *qname, int qcls, int qtyp, int flags, + dns_parse_fn *parse); +UDNS_API void * +dns_resolve(struct dns_ctx *ctx, struct dns_query *q); + + +/* Specific RR handlers */ + +#define dns_rr_common(prefix) \ + char *prefix##_cname; /* canonical name */ \ + char *prefix##_qname; /* original query name */ \ + unsigned prefix##_ttl; /* TTL value */ \ + int prefix##_nrr /* number of records */ + +struct dns_rr_null { /* NULL RRset, aka RRset template */ + dns_rr_common(dnsn); +}; + +UDNS_API int +dns_stdrr_size(const struct dns_parse *p); +UDNS_API void * +dns_stdrr_finish(struct dns_rr_null *ret, char *cp, const struct dns_parse *p); + +struct dns_rr_a4 { /* the A RRset */ + dns_rr_common(dnsa4); + struct in_addr *dnsa4_addr; /* array of addresses, naddr elements */ +}; + +UDNS_API dns_parse_fn dns_parse_a4; /* A RR parsing routine */ +typedef void /* A query callback routine */ +dns_query_a4_fn(struct dns_ctx *ctx, struct dns_rr_a4 *result, void *data); + +/* submit A IN query */ +UDNS_API struct dns_query * +dns_submit_a4(struct dns_ctx *ctx, const char *name, int flags, + dns_query_a4_fn *cbck, void *data); + +/* resolve A IN query */ +UDNS_API struct dns_rr_a4 * +dns_resolve_a4(struct dns_ctx *ctx, const char *name, int flags); + + +struct dns_rr_a6 { /* the AAAA RRset */ + dns_rr_common(dnsa6); + struct in6_addr *dnsa6_addr; /* array of addresses, naddr elements */ +}; + +UDNS_API dns_parse_fn dns_parse_a6; /* A RR parsing routine */ +typedef void /* A query callback routine */ +dns_query_a6_fn(struct dns_ctx *ctx, struct dns_rr_a6 *result, void *data); + +/* submit AAAA IN query */ +UDNS_API struct dns_query * +dns_submit_a6(struct dns_ctx *ctx, const char *name, int flags, + dns_query_a6_fn *cbck, void *data); + +/* resolve AAAA IN query */ +UDNS_API struct dns_rr_a6 * +dns_resolve_a6(struct dns_ctx *ctx, const char *name, int flags); + + +struct dns_rr_ptr { /* the PTR RRset */ + dns_rr_common(dnsptr); + char **dnsptr_ptr; /* array of PTRs */ +}; + +UDNS_API dns_parse_fn dns_parse_ptr; /* PTR RR parsing routine */ +typedef void /* PTR query callback */ +dns_query_ptr_fn(struct dns_ctx *ctx, struct dns_rr_ptr *result, void *data); +/* submit PTR IN in-addr.arpa query */ +UDNS_API struct dns_query * +dns_submit_a4ptr(struct dns_ctx *ctx, const struct in_addr *addr, + dns_query_ptr_fn *cbck, void *data); +/* resolve PTR IN in-addr.arpa query */ +UDNS_API struct dns_rr_ptr * +dns_resolve_a4ptr(struct dns_ctx *ctx, const struct in_addr *addr); + +/* the same as above, but for ip6.arpa */ +UDNS_API struct dns_query * +dns_submit_a6ptr(struct dns_ctx *ctx, const struct in6_addr *addr, + dns_query_ptr_fn *cbck, void *data); +UDNS_API struct dns_rr_ptr * +dns_resolve_a6ptr(struct dns_ctx *ctx, const struct in6_addr *addr); + + +struct dns_mx { /* single MX RR */ + int priority; /* MX priority */ + char *name; /* MX name */ +}; +struct dns_rr_mx { /* the MX RRset */ + dns_rr_common(dnsmx); + struct dns_mx *dnsmx_mx; /* array of MXes */ +}; +UDNS_API dns_parse_fn dns_parse_mx; /* MX RR parsing routine */ +typedef void /* MX RR callback */ +dns_query_mx_fn(struct dns_ctx *ctx, struct dns_rr_mx *result, void *data); +/* submit MX IN query */ +UDNS_API struct dns_query * +dns_submit_mx(struct dns_ctx *ctx, const char *name, int flags, + dns_query_mx_fn *cbck, void *data); +/* resolve MX IN query */ +UDNS_API struct dns_rr_mx * +dns_resolve_mx(struct dns_ctx *ctx, const char *name, int flags); + + +struct dns_txt { /* single TXT record */ + int len; /* length of the text */ + dnsc_t *txt; /* pointer to text buffer. May contain nulls. */ +}; +struct dns_rr_txt { /* the TXT RRset */ + dns_rr_common(dnstxt); + struct dns_txt *dnstxt_txt; /* array of TXT records */ +}; +UDNS_API dns_parse_fn dns_parse_txt; /* TXT RR parsing routine */ +typedef void /* TXT RR callback */ +dns_query_txt_fn(struct dns_ctx *ctx, struct dns_rr_txt *result, void *data); +/* submit TXT query */ +UDNS_API struct dns_query * +dns_submit_txt(struct dns_ctx *ctx, const char *name, int qcls, int flags, + dns_query_txt_fn *cbck, void *data); +/* resolve TXT query */ +UDNS_API struct dns_rr_txt * +dns_resolve_txt(struct dns_ctx *ctx, const char *name, int qcls, int flags); + + +struct dns_srv { /* single SRV RR */ + int priority; /* SRV priority */ + int weight; /* SRV weight */ + int port; /* SRV port */ + char *name; /* SRV name */ +}; +struct dns_rr_srv { /* the SRV RRset */ + dns_rr_common(dnssrv); + struct dns_srv *dnssrv_srv; /* array of SRVes */ +}; +UDNS_API dns_parse_fn dns_parse_srv; /* SRV RR parsing routine */ +typedef void /* SRV RR callback */ +dns_query_srv_fn(struct dns_ctx *ctx, struct dns_rr_srv *result, void *data); +/* submit SRV IN query */ +UDNS_API struct dns_query * +dns_submit_srv(struct dns_ctx *ctx, + const char *name, const char *srv, const char *proto, + int flags, dns_query_srv_fn *cbck, void *data); +/* resolve SRV IN query */ +UDNS_API struct dns_rr_srv * +dns_resolve_srv(struct dns_ctx *ctx, + const char *name, const char *srv, const char *proto, + int flags); + +/* NAPTR (RFC3403) RR type */ +struct dns_naptr { /* single NAPTR RR */ + int order; /* NAPTR order */ + int preference; /* NAPTR preference */ + char *flags; /* NAPTR flags */ + char *service; /* NAPTR service */ + char *regexp; /* NAPTR regexp */ + char *replacement; /* NAPTR replacement */ +}; + +struct dns_rr_naptr { /* the NAPTR RRset */ + dns_rr_common(dnsnaptr); + struct dns_naptr *dnsnaptr_naptr; /* array of NAPTRes */ +}; +UDNS_API dns_parse_fn dns_parse_naptr; /* NAPTR RR parsing routine */ +typedef void /* NAPTR RR callback */ +dns_query_naptr_fn(struct dns_ctx *ctx, + struct dns_rr_naptr *result, void *data); +/* submit NAPTR IN query */ +UDNS_API struct dns_query * +dns_submit_naptr(struct dns_ctx *ctx, const char *name, int flags, + dns_query_naptr_fn *cbck, void *data); +/* resolve NAPTR IN query */ +UDNS_API struct dns_rr_naptr * +dns_resolve_naptr(struct dns_ctx *ctx, const char *name, int flags); + + +UDNS_API struct dns_query * +dns_submit_a4dnsbl(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl, + dns_query_a4_fn *cbck, void *data); +UDNS_API struct dns_query * +dns_submit_a4dnsbl_txt(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl, + dns_query_txt_fn *cbck, void *data); +UDNS_API struct dns_rr_a4 * +dns_resolve_a4dnsbl(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl); +UDNS_API struct dns_rr_txt * +dns_resolve_a4dnsbl_txt(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl); + +UDNS_API struct dns_query * +dns_submit_a6dnsbl(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl, + dns_query_a4_fn *cbck, void *data); +UDNS_API struct dns_query * +dns_submit_a6dnsbl_txt(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl, + dns_query_txt_fn *cbck, void *data); +UDNS_API struct dns_rr_a4 * +dns_resolve_a6dnsbl(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl); +UDNS_API struct dns_rr_txt * +dns_resolve_a6dnsbl_txt(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl); + +UDNS_API struct dns_query * +dns_submit_rhsbl(struct dns_ctx *ctx, + const char *name, const char *rhsbl, + dns_query_a4_fn *cbck, void *data); +UDNS_API struct dns_query * +dns_submit_rhsbl_txt(struct dns_ctx *ctx, + const char *name, const char *rhsbl, + dns_query_txt_fn *cbck, void *data); +UDNS_API struct dns_rr_a4 * +dns_resolve_rhsbl(struct dns_ctx *ctx, const char *name, const char *rhsbl); +UDNS_API struct dns_rr_txt * +dns_resolve_rhsbl_txt(struct dns_ctx *ctx, const char *name, const char *rhsbl); + +/**************************************************************************/ +/**************** Names, Names ********************************************/ + +struct dns_nameval { + int val; + const char *name; +}; + +UDNS_DATA_API extern const struct dns_nameval dns_classtab[]; +UDNS_DATA_API extern const struct dns_nameval dns_typetab[]; +UDNS_DATA_API extern const struct dns_nameval dns_rcodetab[]; +UDNS_API int +dns_findname(const struct dns_nameval *nv, const char *name); +#define dns_findclassname(cls) dns_findname(dns_classtab, (cls)) +#define dns_findtypename(type) dns_findname(dns_typetab, (type)) +#define dns_findrcodename(rcode) dns_findname(dns_rcodetab, (rcode)) + +UDNS_API const char *dns_classname(enum dns_class cls); +UDNS_API const char *dns_typename(enum dns_type type); +UDNS_API const char *dns_rcodename(enum dns_rcode rcode); +const char *_dns_format_code(char *buf, const char *prefix, int code); + +UDNS_API const char *dns_strerror(int errnum); + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* include guard */ diff --git a/libs/udns/udns_bl.c b/libs/udns/udns_bl.c new file mode 100644 index 0000000000..dc6f53b164 --- /dev/null +++ b/libs/udns/udns_bl.c @@ -0,0 +1,160 @@ +/* $Id: udns_bl.c,v 1.10 2005/09/12 10:55:21 mjt Exp $ + DNSBL stuff + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include "udns.h" +#ifndef NULL +# define NULL 0 +#endif + +struct dns_query * +dns_submit_a4dnsbl(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl, + dns_query_a4_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + if (dns_a4ptodn(addr, dnsbl, dn, sizeof(dn)) <= 0) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_A, DNS_NOSRCH, + dns_parse_a4, (dns_query_fn*)cbck, data); +} + +struct dns_query * +dns_submit_a4dnsbl_txt(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl, + dns_query_txt_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + if (dns_a4ptodn(addr, dnsbl, dn, sizeof(dn)) <= 0) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_TXT, DNS_NOSRCH, + dns_parse_txt, (dns_query_fn*)cbck, data); +} + +struct dns_rr_a4 * +dns_resolve_a4dnsbl(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl) { + return (struct dns_rr_a4 *) + dns_resolve(ctx, dns_submit_a4dnsbl(ctx, addr, dnsbl, 0, 0)); +} + +struct dns_rr_txt * +dns_resolve_a4dnsbl_txt(struct dns_ctx *ctx, + const struct in_addr *addr, const char *dnsbl) { + return (struct dns_rr_txt *) + dns_resolve(ctx, dns_submit_a4dnsbl_txt(ctx, addr, dnsbl, 0, 0)); +} + + +struct dns_query * +dns_submit_a6dnsbl(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl, + dns_query_a4_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + if (dns_a6ptodn(addr, dnsbl, dn, sizeof(dn)) <= 0) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_A, DNS_NOSRCH, + dns_parse_a4, (dns_query_fn*)cbck, data); +} + +struct dns_query * +dns_submit_a6dnsbl_txt(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl, + dns_query_txt_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + if (dns_a6ptodn(addr, dnsbl, dn, sizeof(dn)) <= 0) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_TXT, DNS_NOSRCH, + dns_parse_txt, (dns_query_fn*)cbck, data); +} + +struct dns_rr_a4 * +dns_resolve_a6dnsbl(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl) { + return (struct dns_rr_a4 *) + dns_resolve(ctx, dns_submit_a6dnsbl(ctx, addr, dnsbl, 0, 0)); +} + +struct dns_rr_txt * +dns_resolve_a6dnsbl_txt(struct dns_ctx *ctx, + const struct in6_addr *addr, const char *dnsbl) { + return (struct dns_rr_txt *) + dns_resolve(ctx, dns_submit_a6dnsbl_txt(ctx, addr, dnsbl, 0, 0)); +} + +static int +dns_rhsbltodn(const char *name, const char *rhsbl, dnsc_t dn[DNS_MAXDN]) +{ + int l = dns_sptodn(name, dn, DNS_MAXDN); + if (l <= 0) return 0; + l = dns_sptodn(rhsbl, dn+l-1, DNS_MAXDN-l+1); + if (l <= 0) return 0; + return 1; +} + +struct dns_query * +dns_submit_rhsbl(struct dns_ctx *ctx, const char *name, const char *rhsbl, + dns_query_a4_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + if (!dns_rhsbltodn(name, rhsbl, dn)) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_A, DNS_NOSRCH, + dns_parse_a4, (dns_query_fn*)cbck, data); +} +struct dns_query * +dns_submit_rhsbl_txt(struct dns_ctx *ctx, const char *name, const char *rhsbl, + dns_query_txt_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + if (!dns_rhsbltodn(name, rhsbl, dn)) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_TXT, DNS_NOSRCH, + dns_parse_txt, (dns_query_fn*)cbck, data); +} + +struct dns_rr_a4 * +dns_resolve_rhsbl(struct dns_ctx *ctx, const char *name, const char *rhsbl) { + return (struct dns_rr_a4*) + dns_resolve(ctx, dns_submit_rhsbl(ctx, name, rhsbl, 0, 0)); +} + +struct dns_rr_txt * +dns_resolve_rhsbl_txt(struct dns_ctx *ctx, const char *name, const char *rhsbl) +{ + return (struct dns_rr_txt*) + dns_resolve(ctx, dns_submit_rhsbl_txt(ctx, name, rhsbl, 0, 0)); +} diff --git a/libs/udns/udns_codes.c b/libs/udns/udns_codes.c new file mode 100644 index 0000000000..a5ffce7eda --- /dev/null +++ b/libs/udns/udns_codes.c @@ -0,0 +1,171 @@ +/* Automatically generated. */ +#include "udns.h" + +const struct dns_nameval dns_typetab[] = { + {DNS_T_INVALID,"INVALID"}, + {DNS_T_A,"A"}, + {DNS_T_NS,"NS"}, + {DNS_T_MD,"MD"}, + {DNS_T_MF,"MF"}, + {DNS_T_CNAME,"CNAME"}, + {DNS_T_SOA,"SOA"}, + {DNS_T_MB,"MB"}, + {DNS_T_MG,"MG"}, + {DNS_T_MR,"MR"}, + {DNS_T_NULL,"NULL"}, + {DNS_T_WKS,"WKS"}, + {DNS_T_PTR,"PTR"}, + {DNS_T_HINFO,"HINFO"}, + {DNS_T_MINFO,"MINFO"}, + {DNS_T_MX,"MX"}, + {DNS_T_TXT,"TXT"}, + {DNS_T_RP,"RP"}, + {DNS_T_AFSDB,"AFSDB"}, + {DNS_T_X25,"X25"}, + {DNS_T_ISDN,"ISDN"}, + {DNS_T_RT,"RT"}, + {DNS_T_NSAP,"NSAP"}, + {DNS_T_NSAP_PTR,"NSAP_PTR"}, + {DNS_T_SIG,"SIG"}, + {DNS_T_KEY,"KEY"}, + {DNS_T_PX,"PX"}, + {DNS_T_GPOS,"GPOS"}, + {DNS_T_AAAA,"AAAA"}, + {DNS_T_LOC,"LOC"}, + {DNS_T_NXT,"NXT"}, + {DNS_T_EID,"EID"}, + {DNS_T_NIMLOC,"NIMLOC"}, + {DNS_T_SRV,"SRV"}, + {DNS_T_ATMA,"ATMA"}, + {DNS_T_NAPTR,"NAPTR"}, + {DNS_T_KX,"KX"}, + {DNS_T_CERT,"CERT"}, + {DNS_T_A6,"A6"}, + {DNS_T_DNAME,"DNAME"}, + {DNS_T_SINK,"SINK"}, + {DNS_T_OPT,"OPT"}, + {DNS_T_DS,"DS"}, + {DNS_T_NSEC,"NSEC"}, + {DNS_T_TSIG,"TSIG"}, + {DNS_T_IXFR,"IXFR"}, + {DNS_T_AXFR,"AXFR"}, + {DNS_T_MAILB,"MAILB"}, + {DNS_T_MAILA,"MAILA"}, + {DNS_T_ANY,"ANY"}, + {DNS_T_ZXFR,"ZXFR"}, + {DNS_T_MAX,"MAX"}, + {0,0}}; +const char *dns_typename(enum dns_type code) { + static char nm[20]; + switch(code) { + case DNS_T_INVALID: return dns_typetab[0].name; + case DNS_T_A: return dns_typetab[1].name; + case DNS_T_NS: return dns_typetab[2].name; + case DNS_T_MD: return dns_typetab[3].name; + case DNS_T_MF: return dns_typetab[4].name; + case DNS_T_CNAME: return dns_typetab[5].name; + case DNS_T_SOA: return dns_typetab[6].name; + case DNS_T_MB: return dns_typetab[7].name; + case DNS_T_MG: return dns_typetab[8].name; + case DNS_T_MR: return dns_typetab[9].name; + case DNS_T_NULL: return dns_typetab[10].name; + case DNS_T_WKS: return dns_typetab[11].name; + case DNS_T_PTR: return dns_typetab[12].name; + case DNS_T_HINFO: return dns_typetab[13].name; + case DNS_T_MINFO: return dns_typetab[14].name; + case DNS_T_MX: return dns_typetab[15].name; + case DNS_T_TXT: return dns_typetab[16].name; + case DNS_T_RP: return dns_typetab[17].name; + case DNS_T_AFSDB: return dns_typetab[18].name; + case DNS_T_X25: return dns_typetab[19].name; + case DNS_T_ISDN: return dns_typetab[20].name; + case DNS_T_RT: return dns_typetab[21].name; + case DNS_T_NSAP: return dns_typetab[22].name; + case DNS_T_NSAP_PTR: return dns_typetab[23].name; + case DNS_T_SIG: return dns_typetab[24].name; + case DNS_T_KEY: return dns_typetab[25].name; + case DNS_T_PX: return dns_typetab[26].name; + case DNS_T_GPOS: return dns_typetab[27].name; + case DNS_T_AAAA: return dns_typetab[28].name; + case DNS_T_LOC: return dns_typetab[29].name; + case DNS_T_NXT: return dns_typetab[30].name; + case DNS_T_EID: return dns_typetab[31].name; + case DNS_T_NIMLOC: return dns_typetab[32].name; + case DNS_T_SRV: return dns_typetab[33].name; + case DNS_T_ATMA: return dns_typetab[34].name; + case DNS_T_NAPTR: return dns_typetab[35].name; + case DNS_T_KX: return dns_typetab[36].name; + case DNS_T_CERT: return dns_typetab[37].name; + case DNS_T_A6: return dns_typetab[38].name; + case DNS_T_DNAME: return dns_typetab[39].name; + case DNS_T_SINK: return dns_typetab[40].name; + case DNS_T_OPT: return dns_typetab[41].name; + case DNS_T_DS: return dns_typetab[42].name; + case DNS_T_NSEC: return dns_typetab[43].name; + case DNS_T_TSIG: return dns_typetab[44].name; + case DNS_T_IXFR: return dns_typetab[45].name; + case DNS_T_AXFR: return dns_typetab[46].name; + case DNS_T_MAILB: return dns_typetab[47].name; + case DNS_T_MAILA: return dns_typetab[48].name; + case DNS_T_ANY: return dns_typetab[49].name; + case DNS_T_ZXFR: return dns_typetab[50].name; + case DNS_T_MAX: return dns_typetab[51].name; + } + return _dns_format_code(nm,"type",code); +} + +const struct dns_nameval dns_classtab[] = { + {DNS_C_INVALID,"INVALID"}, + {DNS_C_IN,"IN"}, + {DNS_C_CH,"CH"}, + {DNS_C_HS,"HS"}, + {DNS_C_ANY,"ANY"}, + {0,0}}; +const char *dns_classname(enum dns_class code) { + static char nm[20]; + switch(code) { + case DNS_C_INVALID: return dns_classtab[0].name; + case DNS_C_IN: return dns_classtab[1].name; + case DNS_C_CH: return dns_classtab[2].name; + case DNS_C_HS: return dns_classtab[3].name; + case DNS_C_ANY: return dns_classtab[4].name; + } + return _dns_format_code(nm,"class",code); +} + +const struct dns_nameval dns_rcodetab[] = { + {DNS_R_NOERROR,"NOERROR"}, + {DNS_R_FORMERR,"FORMERR"}, + {DNS_R_SERVFAIL,"SERVFAIL"}, + {DNS_R_NXDOMAIN,"NXDOMAIN"}, + {DNS_R_NOTIMPL,"NOTIMPL"}, + {DNS_R_REFUSED,"REFUSED"}, + {DNS_R_YXDOMAIN,"YXDOMAIN"}, + {DNS_R_YXRRSET,"YXRRSET"}, + {DNS_R_NXRRSET,"NXRRSET"}, + {DNS_R_NOTAUTH,"NOTAUTH"}, + {DNS_R_NOTZONE,"NOTZONE"}, + {DNS_R_BADSIG,"BADSIG"}, + {DNS_R_BADKEY,"BADKEY"}, + {DNS_R_BADTIME,"BADTIME"}, + {0,0}}; +const char *dns_rcodename(enum dns_rcode code) { + static char nm[20]; + switch(code) { + case DNS_R_NOERROR: return dns_rcodetab[0].name; + case DNS_R_FORMERR: return dns_rcodetab[1].name; + case DNS_R_SERVFAIL: return dns_rcodetab[2].name; + case DNS_R_NXDOMAIN: return dns_rcodetab[3].name; + case DNS_R_NOTIMPL: return dns_rcodetab[4].name; + case DNS_R_REFUSED: return dns_rcodetab[5].name; + case DNS_R_YXDOMAIN: return dns_rcodetab[6].name; + case DNS_R_YXRRSET: return dns_rcodetab[7].name; + case DNS_R_NXRRSET: return dns_rcodetab[8].name; + case DNS_R_NOTAUTH: return dns_rcodetab[9].name; + case DNS_R_NOTZONE: return dns_rcodetab[10].name; + case DNS_R_BADSIG: return dns_rcodetab[11].name; + case DNS_R_BADKEY: return dns_rcodetab[12].name; + case DNS_R_BADTIME: return dns_rcodetab[13].name; + } + return _dns_format_code(nm,"rcode",code); +} diff --git a/libs/udns/udns_dn.c b/libs/udns/udns_dn.c new file mode 100644 index 0000000000..1264a1dc82 --- /dev/null +++ b/libs/udns/udns_dn.c @@ -0,0 +1,382 @@ +/* $Id: udns_dn.c,v 1.7 2006/11/28 22:45:20 mjt Exp $ + domain names manipulation routines + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include "udns.h" + +unsigned dns_dnlen(dnscc_t *dn) { + register dnscc_t *d = dn; + while(*d) + d += 1 + *d; + return (unsigned)(d - dn) + 1; +} + +unsigned dns_dnlabels(register dnscc_t *dn) { + register unsigned l = 0; + while(*dn) + ++l, dn += 1 + *dn; + return l; +} + +unsigned dns_dnequal(register dnscc_t *dn1, register dnscc_t *dn2) { + register unsigned c; + dnscc_t *dn = dn1; + for(;;) { + if ((c = *dn1++) != *dn2++) + return 0; + if (!c) + return (unsigned)(dn1 - dn); + while(c--) { + if (DNS_DNLC(*dn1) != DNS_DNLC(*dn2)) + return 0; + ++dn1; ++dn2; + } + } +} + +unsigned +dns_dntodn(dnscc_t *sdn, dnsc_t *ddn, unsigned ddnsiz) { + unsigned sdnlen = dns_dnlen(sdn); + if (ddnsiz < sdnlen) + return 0; + memcpy(ddn, sdn, sdnlen); + return sdnlen; +} + +int +dns_ptodn(const char *name, unsigned namelen, + dnsc_t *dn, unsigned dnsiz, int *isabs) +{ + dnsc_t *dp; /* current position in dn (len byte first) */ + dnsc_t *const de /* end of dn: last byte that can be filled up */ + = dn + (dnsiz >= DNS_MAXDN ? DNS_MAXDN : dnsiz) - 1; + dnscc_t *np = (dnscc_t *)name; + dnscc_t *ne = np + (namelen ? namelen : strlen((char*)np)); + dnsc_t *llab; /* start of last label (llab[-1] will be length) */ + unsigned c; /* next input character, or length of last label */ + + if (!dnsiz) + return 0; + dp = llab = dn + 1; + + while(np < ne) { + + if (*np == '.') { /* label delimiter */ + c = dp - llab; /* length of the label */ + if (!c) { /* empty label */ + if (np == (dnscc_t *)name && np + 1 == ne) { + /* special case for root dn, aka `.' */ + ++np; + break; + } + return -1; /* zero label */ + } + if (c > DNS_MAXLABEL) + return -1; /* label too long */ + llab[-1] = (dnsc_t)c; /* update len of last label */ + llab = ++dp; /* start new label, llab[-1] will be len of it */ + ++np; + continue; + } + + /* check whenever we may put out one more byte */ + if (dp >= de) /* too long? */ + return dnsiz >= DNS_MAXDN ? -1 : 0; + if (*np != '\\') { /* non-escape, simple case */ + *dp++ = *np++; + continue; + } + /* handle \-style escape */ + /* note that traditionally, domain names (gethostbyname etc) + * used decimal \dd notation, not octal \ooo (RFC1035), so + * we're following this tradition here. + */ + if (++np == ne) + return -1; /* bad escape */ + else if (*np >= '0' && *np <= '9') { /* decimal number */ + /* we allow not only exactly 3 digits as per RFC1035, + * but also 2 or 1, for better usability. */ + c = *np++ - '0'; + if (np < ne && *np >= '0' && *np <= '9') { /* 2digits */ + c = c * 10 + *np++ - '0'; + if (np < ne && *np >= '0' && *np <= '9') { + c = c * 10 + *np++ - '0'; + if (c > 255) + return -1; /* bad escape */ + } + } + } + else + c = *np++; + *dp++ = (dnsc_t)c; /* place next out byte */ + } + + if ((c = dp - llab) > DNS_MAXLABEL) + return -1; /* label too long */ + if ((llab[-1] = (dnsc_t)c) != 0) { + *dp++ = 0; + if (isabs) + *isabs = 0; + } + else if (isabs) + *isabs = 1; + + return dp - dn; +} + +dnscc_t dns_inaddr_arpa_dn[14] = "\07in-addr\04arpa"; + +dnsc_t * +dns_a4todn_(const struct in_addr *addr, dnsc_t *dn, dnsc_t *dne) { + dnsc_t *p; + unsigned n; + dnscc_t *s = ((dnscc_t *)addr) + 4; + while(--s >= (dnscc_t *)addr) { + n = *s; + p = dn + 1; + if (n > 99) { + if (p + 2 > dne) return 0; + *p++ = n / 100 + '0'; + *p++ = (n % 100 / 10) + '0'; + *p = n % 10 + '0'; + } + else if (n > 9) { + if (p + 1 > dne) return 0; + *p++ = n / 10 + '0'; + *p = n % 10 + '0'; + } + else { + if (p > dne) return 0; + *p = n + '0'; + } + *dn = p - dn; + dn = p + 1; + } + return dn; +} + +int dns_a4todn(const struct in_addr *addr, dnscc_t *tdn, + dnsc_t *dn, unsigned dnsiz) { + dnsc_t *dne = dn + (dnsiz > DNS_MAXDN ? DNS_MAXDN : dnsiz); + dnsc_t *p; + unsigned l; + p = dns_a4todn_(addr, dn, dne); + if (!p) return 0; + if (!tdn) + tdn = dns_inaddr_arpa_dn; + l = dns_dnlen(tdn); + if (p + l > dne) return dnsiz >= DNS_MAXDN ? -1 : 0; + memcpy(p, tdn, l); + return (p + l) - dn; +} + +int dns_a4ptodn(const struct in_addr *addr, const char *tname, + dnsc_t *dn, unsigned dnsiz) { + dnsc_t *p; + int r; + if (!tname) + return dns_a4todn(addr, NULL, dn, dnsiz); + p = dns_a4todn_(addr, dn, dn + dnsiz); + if (!p) return 0; + r = dns_sptodn(tname, p, dnsiz - (p - dn)); + return r != 0 ? r : dnsiz >= DNS_MAXDN ? -1 : 0; +} + +dnscc_t dns_ip6_arpa_dn[10] = "\03ip6\04arpa"; + +dnsc_t * +dns_a6todn_(const struct in6_addr *addr, dnsc_t *dn, dnsc_t *dne) { + unsigned n; + dnscc_t *s = ((dnscc_t *)addr) + 16; + if (dn + 64 > dne) return 0; + while(--s >= (dnscc_t *)addr) { + *dn++ = 1; + n = *s & 0x0f; + *dn++ = n > 9 ? n + 'a' - 10 : n + '0'; + *dn++ = 1; + n = *s >> 4; + *dn++ = n > 9 ? n + 'a' - 10 : n + '0'; + } + return dn; +} + +int dns_a6todn(const struct in6_addr *addr, dnscc_t *tdn, + dnsc_t *dn, unsigned dnsiz) { + dnsc_t *dne = dn + (dnsiz > DNS_MAXDN ? DNS_MAXDN : dnsiz); + dnsc_t *p; + unsigned l; + p = dns_a6todn_(addr, dn, dne); + if (!p) return 0; + if (!tdn) + tdn = dns_ip6_arpa_dn; + l = dns_dnlen(tdn); + if (p + l > dne) return dnsiz >= DNS_MAXDN ? -1 : 0; + memcpy(p, tdn, l); + return (p + l) - dn; +} + +int dns_a6ptodn(const struct in6_addr *addr, const char *tname, + dnsc_t *dn, unsigned dnsiz) { + dnsc_t *p; + int r; + if (!tname) + return dns_a6todn(addr, NULL, dn, dnsiz); + p = dns_a6todn_(addr, dn, dn + dnsiz); + if (!p) return 0; + r = dns_sptodn(tname, p, dnsiz - (p - dn)); + return r != 0 ? r : dnsiz >= DNS_MAXDN ? -1 : 0; +} + +/* return size of buffer required to convert the dn into asciiz string. + * Keep in sync with dns_dntop() below. + */ +unsigned dns_dntop_size(dnscc_t *dn) { + unsigned size = 0; /* the size reqd */ + dnscc_t *le; /* label end */ + + while(*dn) { + /* *dn is the length of the next label, non-zero */ + if (size) + ++size; /* for the dot */ + le = dn + *dn + 1; + ++dn; + do { + switch(*dn) { + case '.': + case '\\': + /* Special modifiers in zone files. */ + case '"': + case ';': + case '@': + case '$': + size += 2; + break; + default: + if (*dn <= 0x20 || *dn >= 0x7f) + /* \ddd decimal notation */ + size += 4; + else + size += 1; + } + } while(++dn < le); + } + size += 1; /* zero byte at the end - string terminator */ + return size > DNS_MAXNAME ? 0 : size; +} + +/* Convert the dn into asciiz string. + * Keep in sync with dns_dntop_size() above. + */ +int dns_dntop(dnscc_t *dn, char *name, unsigned namesiz) { + char *np = name; /* current name ptr */ + char *const ne = name + namesiz; /* end of name */ + dnscc_t *le; /* label end */ + + while(*dn) { + /* *dn is the length of the next label, non-zero */ + if (np != name) { + if (np >= ne) goto toolong; + *np++ = '.'; + } + le = dn + *dn + 1; + ++dn; + do { + switch(*dn) { + case '.': + case '\\': + /* Special modifiers in zone files. */ + case '"': + case ';': + case '@': + case '$': + if (np + 2 > ne) goto toolong; + *np++ = '\\'; + *np++ = *dn; + break; + default: + if (*dn <= 0x20 || *dn >= 0x7f) { + /* \ddd decimal notation */ + if (np + 4 >= ne) goto toolong; + *np++ = '\\'; + *np++ = '0' + (*dn / 100); + *np++ = '0' + ((*dn % 100) / 10); + *np++ = '0' + (*dn % 10); + } + else { + if (np >= ne) goto toolong; + *np++ = *dn; + } + } + } while(++dn < le); + } + if (np >= ne) goto toolong; + *np++ = '\0'; + return np - name; +toolong: + return namesiz >= DNS_MAXNAME ? -1 : 0; +} + +#ifdef TEST +#include +#include + +int main(int argc, char **argv) { + int i; + int sz; + dnsc_t dn[DNS_MAXDN+10]; + dnsc_t *dl, *dp; + int isabs; + + sz = (argc > 1) ? atoi(argv[1]) : 0; + + for(i = 2; i < argc; ++i) { + int r = dns_ptodn(argv[i], 0, dn, sz, &isabs); + printf("%s: ", argv[i]); + if (r < 0) printf("error\n"); + else if (!r) printf("buffer too small\n"); + else { + printf("len=%d dnlen=%d size=%d name:", + r, dns_dnlen(dn), dns_dntop_size(dn)); + dl = dn; + while(*dl) { + printf(" %d=", *dl); + dp = dl + 1; + dl = dp + *dl; + while(dp < dl) { + if (*dp <= ' ' || *dp >= 0x7f) + printf("\\%03d", *dp); + else if (*dp == '.' || *dp == '\\') + printf("\\%c", *dp); + else + putchar(*dp); + ++dp; + } + } + if (isabs) putchar('.'); + putchar('\n'); + } + } + return 0; +} + +#endif /* TEST */ diff --git a/libs/udns/udns_dntosp.c b/libs/udns/udns_dntosp.c new file mode 100644 index 0000000000..933463e05a --- /dev/null +++ b/libs/udns/udns_dntosp.c @@ -0,0 +1,30 @@ +/* $Id: udns_dntosp.c,v 1.5 2005/04/19 21:48:09 mjt Exp $ + dns_dntosp() = convert DN to asciiz string using static buffer + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include "udns.h" + +static char name[DNS_MAXNAME]; + +const char *dns_dntosp(dnscc_t *dn) { + return dns_dntop(dn, name, sizeof(name)) > 0 ? name : 0; +} diff --git a/libs/udns/udns_misc.c b/libs/udns/udns_misc.c new file mode 100644 index 0000000000..0db7ffd145 --- /dev/null +++ b/libs/udns/udns_misc.c @@ -0,0 +1,67 @@ +/* $Id: udns_misc.c,v 1.8 2005/04/05 22:51:32 mjt Exp $ + miscellaneous routines + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include "udns.h" + +int dns_findname(const struct dns_nameval *nv, const char *name) { + register const char *a, *b; + for(; nv->name; ++nv) + for(a = name, b = nv->name; ; ++a, ++b) + if (DNS_DNUC(*a) != *b) break; + else if (!*a) return nv->val; + return -1; +} + +const char *_dns_format_code(char *buf, const char *prefix, int code) { + char *bp = buf; + unsigned c, n; + do *bp++ = DNS_DNUC(*prefix); + while(*++prefix); + *bp++ = '#'; + if (code < 0) code = -code, *bp++ = '-'; + n = 0; c = code; + do ++n; + while((c /= 10)); + c = code; + bp[n--] = '\0'; + do bp[n--] = c % 10 + '0'; + while((c /= 10)); + return buf; +} + +const char *dns_strerror(int err) { + if (err >= 0) return "successeful completion"; + switch(err) { + case DNS_E_TEMPFAIL: return "temporary failure in name resolution"; + case DNS_E_PROTOCOL: return "protocol error"; + case DNS_E_NXDOMAIN: return "domain name does not exist"; + case DNS_E_NODATA: return "valid domain but no data of requested type"; + case DNS_E_NOMEM: return "out of memory"; + case DNS_E_BADQUERY: return "malformed query"; + default: return "unknown error"; + } +} + +const char *dns_version(void) { + return UDNS_VERSION; +} diff --git a/libs/udns/udns_parse.c b/libs/udns/udns_parse.c new file mode 100644 index 0000000000..5440d92414 --- /dev/null +++ b/libs/udns/udns_parse.c @@ -0,0 +1,169 @@ +/* $Id: udns_parse.c,v 1.14 2005/09/12 10:55:21 mjt Exp $ + raw DNS packet parsing routines + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include "udns.h" + +dnscc_t *dns_skipdn(dnscc_t *cur, dnscc_t *end) { + unsigned c; + for(;;) { + if (cur >= end) + return NULL; + c = *cur++; + if (!c) + return cur; + if (c & 192) /* jump */ + return cur + 1 >= end ? NULL : cur + 1; + cur += c; + } +} + +int +dns_getdn(dnscc_t *pkt, dnscc_t **cur, dnscc_t *end, + register dnsc_t *dn, unsigned dnsiz) { + unsigned c; + dnscc_t *pp = *cur; /* current packet pointer */ + dnsc_t *dp = dn; /* current dn pointer */ + dnsc_t *const de /* end of the DN dest */ + = dn + (dnsiz < DNS_MAXDN ? dnsiz : DNS_MAXDN); + dnscc_t *jump = NULL; /* ptr after first jump if any */ + unsigned loop = 100; /* jump loop counter */ + + for(;;) { /* loop by labels */ + if (pp >= end) /* reached end of packet? */ + return -1; + c = *pp++; /* length of the label */ + if (!c) { /* empty label: terminate */ + if (dn >= de) /* can't fit terminator */ + goto noroom; + *dp++ = 0; + /* return next pos: either after the first jump or current */ + *cur = jump ? jump : pp; + return dp - dn; + } + if (c & 192) { /* jump */ + if (pp >= end) /* eop instead of jump pos */ + return -1; + if (!jump) jump = pp + 1; /* remember first jump */ + else if (!--loop) return -1; /* too many jumps */ + c = ((c & ~192) << 8) | *pp; /* new pos */ + if (c < DNS_HSIZE) /* don't allow jump into the header */ + return -1; + pp = pkt + c; + continue; + } + if (c > DNS_MAXLABEL) /* too long label? */ + return -1; + if (pp + c > end) /* label does not fit in packet? */ + return -1; + if (dp + c + 1 > de) /* if enouth room for the label */ + goto noroom; + *dp++ = c; /* label length */ + memcpy(dp, pp, c); /* and the label itself */ + dp += c; + pp += c; /* advance to the next label */ + } +noroom: + return dnsiz < DNS_MAXDN ? 0 : -1; +} + +void dns_rewind(struct dns_parse *p, dnscc_t *qdn) { + p->dnsp_qdn = qdn; + p->dnsp_cur = p->dnsp_ans; + p->dnsp_rrl = dns_numan(p->dnsp_pkt); + p->dnsp_ttl = 0xffffffffu; + p->dnsp_nrr = 0; +} + +void +dns_initparse(struct dns_parse *p, dnscc_t *qdn, + dnscc_t *pkt, dnscc_t *cur, dnscc_t *end) { + p->dnsp_pkt = pkt; + p->dnsp_end = end; + p->dnsp_rrl = dns_numan(pkt); + p->dnsp_qdn = qdn; + assert(cur + 4 <= end); + if ((p->dnsp_qtyp = dns_get16(cur+0)) == DNS_T_ANY) p->dnsp_qtyp = 0; + if ((p->dnsp_qcls = dns_get16(cur+2)) == DNS_C_ANY) p->dnsp_qcls = 0; + p->dnsp_cur = p->dnsp_ans = cur + 4; + p->dnsp_ttl = 0xffffffffu; + p->dnsp_nrr = 0; +} + +int dns_nextrr(struct dns_parse *p, struct dns_rr *rr) { + dnscc_t *cur = p->dnsp_cur; + while(p->dnsp_rrl > 0) { + --p->dnsp_rrl; + if (dns_getdn(p->dnsp_pkt, &cur, p->dnsp_end, + rr->dnsrr_dn, sizeof(rr->dnsrr_dn)) <= 0) + return -1; + if (cur + 10 > p->dnsp_end) + return -1; + rr->dnsrr_typ = dns_get16(cur); + rr->dnsrr_cls = dns_get16(cur+2); + rr->dnsrr_ttl = dns_get32(cur+4); + rr->dnsrr_dsz = dns_get16(cur+8); + rr->dnsrr_dptr = cur = cur + 10; + rr->dnsrr_dend = cur = cur + rr->dnsrr_dsz; + if (cur > p->dnsp_end) + return -1; + if (p->dnsp_qdn && !dns_dnequal(p->dnsp_qdn, rr->dnsrr_dn)) + continue; + if ((!p->dnsp_qcls || p->dnsp_qcls == rr->dnsrr_cls) && + (!p->dnsp_qtyp || p->dnsp_qtyp == rr->dnsrr_typ)) { + p->dnsp_cur = cur; + ++p->dnsp_nrr; + if (p->dnsp_ttl > rr->dnsrr_ttl) p->dnsp_ttl = rr->dnsrr_ttl; + return 1; + } + if (p->dnsp_qdn && rr->dnsrr_typ == DNS_T_CNAME && !p->dnsp_nrr) { + if (dns_getdn(p->dnsp_pkt, &rr->dnsrr_dptr, p->dnsp_end, + p->dnsp_dnbuf, sizeof(p->dnsp_dnbuf)) <= 0 || + rr->dnsrr_dptr != rr->dnsrr_dend) + return -1; + p->dnsp_qdn = p->dnsp_dnbuf; + if (p->dnsp_ttl > rr->dnsrr_ttl) p->dnsp_ttl = rr->dnsrr_ttl; + } + } + p->dnsp_cur = cur; + return 0; +} + +int dns_stdrr_size(const struct dns_parse *p) { + return + dns_dntop_size(p->dnsp_qdn) + + (p->dnsp_qdn == dns_payload(p->dnsp_pkt) ? 0 : + dns_dntop_size(dns_payload(p->dnsp_pkt))); +} + +void *dns_stdrr_finish(struct dns_rr_null *ret, char *cp, + const struct dns_parse *p) { + cp += dns_dntop(p->dnsp_qdn, (ret->dnsn_cname = cp), DNS_MAXNAME); + if (p->dnsp_qdn == dns_payload(p->dnsp_pkt)) + ret->dnsn_qname = ret->dnsn_cname; + else + dns_dntop(dns_payload(p->dnsp_pkt), (ret->dnsn_qname = cp), DNS_MAXNAME); + ret->dnsn_ttl = p->dnsp_ttl; + return ret; +} diff --git a/libs/udns/udns_resolver.c b/libs/udns/udns_resolver.c new file mode 100644 index 0000000000..f6a647e3cf --- /dev/null +++ b/libs/udns/udns_resolver.c @@ -0,0 +1,1334 @@ +/* $Id: udns_resolver.c,v 1.57 2006/11/29 01:17:43 mjt Exp $ + resolver stuff (main module) + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#ifdef WIN32 +# include /* includes */ +# include /* needed for struct in6_addr */ +# include /* for dns server addresses etc */ +# undef HAVE_POLL +#else +# include +# include +# include +# include /* for inet_pton() */ +# include +# include +# include +# ifdef HAVE_CONFIG_H +# include +# endif +# ifdef HAVE_POLL +# include +# endif +# define closesocket(sock) close(sock) +#endif /* !WIN32 */ + +#include +#include +#include +#include +#include +#include +#include "udns.h" + +#define DNS_QEXTRA 16 /* size of extra buffer space */ +#define DNS_QBUF DNS_HSIZE+DNS_MAXDN+DNS_QEXTRA + +#if !defined(HAVE_INET6) && defined(AF_INET6) +# define HAVE_INET6 1 +#endif +#ifdef NO_INET6 +# undef HAVE_INET6 +#endif + +#ifndef EAFNOSUPPORT +# define EAFNOSUPPORT EINVAL +#endif + +union sockaddr_ns { + struct sockaddr sa; + struct sockaddr_in sin; +#if HAVE_INET6 + struct sockaddr_in6 sin6; +#endif +}; + +struct dns_qlink { + struct dns_query *next, *prev; +}; + +struct dns_query { + struct dns_qlink dnsq_link; /* list entry (should be first) */ + dnsc_t dnsq_buf[DNS_QBUF]; /* the query buffer */ + enum dns_class dnsq_cls; /* requested RR class */ + enum dns_type dnsq_typ; /* requested RR type */ + unsigned dnsq_len; /* length of the query packet */ + unsigned dnsq_origdnl; /* original length of the dnsq_dn */ + unsigned dnsq_flags; /* control flags for this query */ + unsigned dnsq_servi; /* index of next server to try */ + unsigned dnsq_servwait; /* bitmask: servers left to wait */ + unsigned dnsq_servskip; /* bitmask: servers to skip */ + unsigned dnsq_try; /* number of tries made so far */ + unsigned dnsq_srchi; /* current search index */ + time_t dnsq_deadline; /* when current try will expire */ + dns_parse_fn *dnsq_parse; /* parse: raw => application */ + dns_query_fn *dnsq_cbck; /* the callback to call when done */ + void *dnsq_cbdata; /* user data for the callback */ +#ifndef NDEBUG + struct dns_ctx *dnsq_ctx; /* the resolver context */ +#endif +}; + +/* working with dns_query lists */ + +static __inline void qlist_init(struct dns_qlink *list) { + list->next = list->prev = (struct dns_query *)list; +} + +static __inline int qlist_empty(const struct dns_qlink *list) { + return list->next == (const struct dns_query *)list ? 1 : 0; +} + +static __inline struct dns_query *qlist_first(struct dns_qlink *list) { + return list->next == (struct dns_query *)list ? 0 : list->next; +} + +static __inline void qlist_remove(struct dns_query *q) { + q->dnsq_link.next->dnsq_link.prev = q->dnsq_link.prev; + q->dnsq_link.prev->dnsq_link.next = q->dnsq_link.next; +} + +static __inline struct dns_query *qlist_pop(struct dns_qlink *list) { + struct dns_query *q = list->next; + if (q == (struct dns_query *)list) + return NULL; + qlist_remove(q); + return q; +} + +/* insert q between prev and next */ +static __inline void +qlist_insert(struct dns_query *q, + struct dns_query *prev, struct dns_query *next) { + q->dnsq_link.next = next; + q->dnsq_link.prev = prev; + prev->dnsq_link.next = next->dnsq_link.prev = q; +} + +static __inline void +qlist_insert_after(struct dns_query *q, struct dns_query *prev) { + qlist_insert(q, prev, prev->dnsq_link.next); +} + +static __inline void +qlist_insert_before(struct dns_query *q, struct dns_query *next) { + qlist_insert(q, next->dnsq_link.prev, next); +} + +static __inline void +qlist_add_tail(struct dns_query *q, struct dns_qlink *top) { + qlist_insert_before(q, (struct dns_query *)top); +} + +static __inline void +qlist_add_head(struct dns_query *q, struct dns_qlink *top) { + qlist_insert_after(q, (struct dns_query *)top); +} + +#define QLIST_FIRST(list, direction) ((list)->direction) +#define QLIST_ISLAST(list, q) ((q) == (struct dns_query*)(list)) +#define QLIST_NEXT(q, direction) ((q)->dnsq_link.direction) + +#define QLIST_FOR_EACH(list, q, direction) \ + for(q = QLIST_FIRST(list, direction); \ + !QLIST_ISLAST(list, q); q = QLIST_NEXT(q, direction)) + +struct dns_ctx { /* resolver context */ + /* settings */ + unsigned dnsc_flags; /* various flags */ + unsigned dnsc_timeout; /* timeout (base value) for queries */ + unsigned dnsc_ntries; /* number of retries */ + unsigned dnsc_ndots; /* ndots to assume absolute name */ + unsigned dnsc_port; /* default port (DNS_PORT) */ + unsigned dnsc_udpbuf; /* size of UDP buffer */ + /* array of nameserver addresses */ + union sockaddr_ns dnsc_serv[DNS_MAXSERV]; + unsigned dnsc_nserv; /* number of nameservers */ + unsigned dnsc_salen; /* length of socket addresses */ + /* search list for unqualified names */ + dnsc_t dnsc_srch[DNS_MAXSRCH][DNS_MAXDN]; + unsigned dnsc_nsrch; /* number of srch[] */ + + dns_utm_fn *dnsc_utmfn; /* register/cancel timer events */ + void *dnsc_utmctx; /* user timer context for utmfn() */ + time_t dnsc_utmexp; /* when user timer expires */ + + dns_dbgfn *dnsc_udbgfn; /* debugging function */ + + /* dynamic data */ + unsigned short dnsc_nextid; /* next queue ID to use */ + int dnsc_udpsock; /* UDP socket */ + struct dns_qlink dnsc_qactive; /* active list sorted by deadline */ + int dnsc_nactive; /* number entries in dnsc_qactive */ + dnsc_t *dnsc_pbuf; /* packet buffer (udpbuf size) */ + int dnsc_qstatus; /* last query status value */ +}; + +static const struct { + const char *name; + enum dns_opt opt; + unsigned offset; + unsigned min, max; +} dns_opts[] = { +#define opt(name,opt,field,min,max) \ + {name,opt,offsetof(struct dns_ctx,field),min,max} + opt("retrans", DNS_OPT_TIMEOUT, dnsc_timeout, 1,300), + opt("timeout", DNS_OPT_TIMEOUT, dnsc_timeout, 1,300), + opt("retry", DNS_OPT_NTRIES, dnsc_ntries, 1,50), + opt("attempts", DNS_OPT_NTRIES, dnsc_ntries, 1,50), + opt("ndots", DNS_OPT_NDOTS, dnsc_ndots, 0,1000), + opt("port", DNS_OPT_PORT, dnsc_port, 1,0xffff), + opt("udpbuf", DNS_OPT_UDPSIZE, dnsc_udpbuf, DNS_MAXPACKET,65536), +#undef opt +}; +#define dns_ctxopt(ctx,offset) (*((unsigned*)(((char*)ctx)+offset))) + +#define ISSPACE(x) (x == ' ' || x == '\t' || x == '\r' || x == '\n') + +static const char space[] = " \t\r\n"; + +struct dns_ctx dns_defctx; + +#define SETCTX(ctx) if (!ctx) ctx = &dns_defctx +#define SETCTXINITED(ctx) SETCTX(ctx); assert(CTXINITED(ctx)) +#define CTXINITED(ctx) (ctx->dnsc_flags & DNS_INITED) +#define SETCTXFRESH(ctx) SETCTXINITED(ctx); assert(!CTXOPEN(ctx)) +#define SETCTXINACTIVE(ctx) SETCTXINITED(ctx); assert(qlist_empty(&ctx->dnsc_qactive)) +#define SETCTXOPEN(ctx) SETCTXINITED(ctx); assert(CTXOPEN(ctx)) +#define CTXOPEN(ctx) (ctx->dnsc_udpsock >= 0) + +#if defined(NDEBUG) || !defined(DEBUG) +#define dns_assert_ctx(ctx) +#else +static void dns_assert_ctx(const struct dns_ctx *ctx) { + int nactive = 0; + const struct dns_query *q; + QLIST_FOR_EACH(&ctx->dnsc_qactive, q, next) { + assert(q->dnsq_ctx == ctx); + assert(q->dnsq_link.next->dnsq_link.prev == q); + assert(q->dnsq_link.prev->dnsq_link.next == q); + ++nactive; + } + assert(nactive == ctx->dnsc_nactive); +} +#endif + +enum { + DNS_INTERNAL = 0xffff, /* internal flags mask */ + DNS_INITED = 0x0001, /* the context is initialized */ + DNS_ASIS_DONE = 0x0002, /* search: skip the last as-is query */ + DNS_SEEN_NODATA = 0x0004, /* search: NODATA has been received */ + DNS_SEEN_FAIL = 0x0008, /* search: SERVFAIL has been received */ + DNS_SEEN_WRONG = 0x0010, /* search: something wrong happened */ +}; + +static int dns_add_serv_internal(struct dns_ctx *ctx, const char *serv) { + union sockaddr_ns *sns; + if (!serv) + return (ctx->dnsc_nserv = 0); + if (ctx->dnsc_nserv >= DNS_MAXSERV) + return errno = ENFILE, -1; + sns = &ctx->dnsc_serv[ctx->dnsc_nserv]; + memset(sns, 0, sizeof(*sns)); +#if HAVE_INET6 + { struct in_addr addr; + struct in6_addr addr6; + if (inet_pton(AF_INET, serv, &addr) > 0) { + sns->sin.sin_family = AF_INET; + sns->sin.sin_addr = addr; + return ++ctx->dnsc_nserv; + } + if (inet_pton(AF_INET6, serv, &addr6) > 0) { + sns->sin6.sin6_family = AF_INET6; + sns->sin6.sin6_addr = addr6; + return ++ctx->dnsc_nserv; + } + } +#else + { struct in_addr addr; + if (inet_aton(serv, &addr) > 0) { + sns->sin.sin_family = AF_INET; + sns->sin.sin_addr = addr; + return ++ctx->dnsc_nserv; + } + } +#endif + errno = EINVAL; + return -1; +} + +int dns_add_serv(struct dns_ctx *ctx, const char *serv) { + SETCTXFRESH(ctx); + return dns_add_serv_internal(ctx, serv); +} + +static void dns_set_serv_internal(struct dns_ctx *ctx, char *serv) { + ctx->dnsc_nserv = 0; + for(serv = strtok(serv, space); serv; serv = strtok(NULL, space)) + dns_add_serv_internal(ctx, serv); +} + +static int +dns_add_serv_s_internal(struct dns_ctx *ctx, const struct sockaddr *sa) { + if (!sa) + return (ctx->dnsc_nserv = 0); + if (ctx->dnsc_nserv >= DNS_MAXSERV) + return errno = ENFILE, -1; +#if HAVE_INET6 + else if (sa->sa_family == AF_INET6) + ctx->dnsc_serv[ctx->dnsc_nserv].sin6 = *(struct sockaddr_in6*)sa; +#endif + else if (sa->sa_family == AF_INET) + ctx->dnsc_serv[ctx->dnsc_nserv].sin = *(struct sockaddr_in*)sa; + else + return errno = EAFNOSUPPORT, -1; + return ++ctx->dnsc_nserv; +} + +int dns_add_serv_s(struct dns_ctx *ctx, const struct sockaddr *sa) { + SETCTXFRESH(ctx); + return dns_add_serv_s_internal(ctx, sa); +} + +static void dns_set_opts_internal(struct dns_ctx *ctx, const char *opts) { + unsigned i, v; + for(;;) { + while(ISSPACE(*opts)) ++opts; + if (!*opts) break; + for(i = 0; i < sizeof(dns_opts)/sizeof(dns_opts[0]); ++i) { + v = strlen(dns_opts[i].name); + if (strncmp(dns_opts[i].name, opts, v) != 0 || + (opts[v] != ':' && opts[v] != '=')) + continue; + opts += v + 1; + v = 0; + if (*opts < '0' || *opts > '9') break; + do v = v * 10 + (*opts++ - '0'); + while (*opts >= '0' && *opts <= '9'); + if (dns_opts[i].min && v < dns_opts[i].min) v = dns_opts[i].min; + else if (v > dns_opts[i].max) v = dns_opts[i].max; + dns_ctxopt(ctx, dns_opts[i].offset) = v; + break; + } + while(*opts && !ISSPACE(*opts)) ++opts; + } +} + +int dns_set_opts(struct dns_ctx *ctx, const char *opts) { + SETCTXINACTIVE(ctx); + dns_set_opts_internal(ctx, opts); + return 0; +} + +int dns_set_opt(struct dns_ctx *ctx, enum dns_opt opt, int val) { + int prev; + unsigned i; + SETCTXINACTIVE(ctx); + for(i = 0; i < sizeof(dns_opts)/sizeof(dns_opts[0]); ++i) { + if (dns_opts[i].opt != opt) continue; + prev = dns_ctxopt(ctx, dns_opts[i].offset); + if (val >= 0) { + unsigned v = val; + if (v < dns_opts[i].min || v > dns_opts[i].max) { + errno = EINVAL; + return -1; + } + dns_ctxopt(ctx, dns_opts[i].offset) = v; + } + return prev; + } + if (opt == DNS_OPT_FLAGS) { + prev = ctx->dnsc_flags & ~DNS_INTERNAL; + if (val >= 0) + ctx->dnsc_flags = + (ctx->dnsc_flags & DNS_INTERNAL) | (val & ~DNS_INTERNAL); + return prev; + } + errno = ENOSYS; + return -1; +} + +static int dns_add_srch_internal(struct dns_ctx *ctx, const char *srch) { + if (!srch) + return (ctx->dnsc_nsrch = 0); + else if (ctx->dnsc_nsrch >= DNS_MAXSRCH) + return errno = ENFILE, -1; + else if (dns_sptodn(srch, ctx->dnsc_srch[ctx->dnsc_nsrch], DNS_MAXDN) <= 0) + return errno = EINVAL, -1; + else + return ++ctx->dnsc_nsrch; +} + +int dns_add_srch(struct dns_ctx *ctx, const char *srch) { + SETCTXINACTIVE(ctx); + return dns_add_srch_internal(ctx, srch); +} + +static void dns_set_srch_internal(struct dns_ctx *ctx, char *srch) { + ctx->dnsc_nsrch = 0; + for(srch = strtok(srch, space); srch; srch = strtok(NULL, space)) + dns_add_srch_internal(ctx, srch); +} + +static void dns_drop_utm(struct dns_ctx *ctx) { + if (ctx->dnsc_utmfn) + ctx->dnsc_utmfn(NULL, -1, ctx->dnsc_utmctx); + ctx->dnsc_utmctx = NULL; + ctx->dnsc_utmexp = -1; +} + +static void +dns_request_utm(struct dns_ctx *ctx, time_t now) { + struct dns_query *q; + time_t deadline; + int timeout; + if (!ctx->dnsc_utmfn) + return; + q = QLIST_FIRST(&ctx->dnsc_qactive, next); + if (QLIST_ISLAST(&ctx->dnsc_qactive, q)) + deadline = -1, timeout = -1; + else if (!now || q->dnsq_deadline <= now) + deadline = 0, timeout = 0; + else + deadline = q->dnsq_deadline, timeout = deadline - now; + if (ctx->dnsc_utmexp == deadline) + return; + ctx->dnsc_utmfn(ctx, timeout, ctx->dnsc_utmctx); + ctx->dnsc_utmexp = deadline; +} + +void dns_set_dbgfn(struct dns_ctx *ctx, dns_dbgfn *dbgfn) { + SETCTXINITED(ctx); + ctx->dnsc_udbgfn = dbgfn; +} + +void +dns_set_tmcbck(struct dns_ctx *ctx, dns_utm_fn *fn, void *data) { + SETCTXINITED(ctx); + dns_drop_utm(ctx); + ctx->dnsc_utmfn = fn; + ctx->dnsc_utmctx = data; +} + +static void dns_firstid(struct dns_ctx *ctx) { + struct timeval tv; + gettimeofday(&tv, NULL); + ctx->dnsc_nextid = (tv.tv_usec ^ getpid()) & 0xffff; +} + +#ifdef WIN32 + +typedef DWORD (WINAPI *GetAdaptersAddressesFunc)( + ULONG Family, DWORD Flags, PVOID Reserved, + PIP_ADAPTER_ADDRESSES pAdapterAddresses, + PULONG pOutBufLen); + +static int dns_initns_iphlpapi(struct dns_ctx *ctx) { + HANDLE h_iphlpapi; + GetAdaptersAddressesFunc pfnGetAdAddrs; + PIP_ADAPTER_ADDRESSES pAddr, pAddrBuf; + PIP_ADAPTER_DNS_SERVER_ADDRESS pDnsAddr; + ULONG ulOutBufLen; + DWORD dwRetVal; + int ret = -1; + + h_iphlpapi = LoadLibrary("iphlpapi.dll"); + if (!h_iphlpapi) + return -1; + pfnGetAdAddrs = (GetAdaptersAddressesFunc) + GetProcAddress(h_iphlpapi, "GetAdaptersAddresses"); + if (!pfnGetAdAddrs) goto freelib; + ulOutBufLen = 0; + dwRetVal = pfnGetAdAddrs(AF_UNSPEC, 0, NULL, NULL, &ulOutBufLen); + if (dwRetVal != ERROR_BUFFER_OVERFLOW) goto freelib; + pAddrBuf = malloc(ulOutBufLen); + if (!pAddrBuf) goto freelib; + dwRetVal = pfnGetAdAddrs(AF_UNSPEC, 0, NULL, pAddrBuf, &ulOutBufLen); + if (dwRetVal != ERROR_SUCCESS) goto freemem; + for (pAddr = pAddrBuf; + pAddr && ctx->dnsc_nserv <= DNS_MAXSERV; + pAddr = pAddr->Next) + for (pDnsAddr = pAddr->FirstDnsServerAddress; + pDnsAddr && ctx->dnsc_nserv <= DNS_MAXSERV; + pDnsAddr = pDnsAddr->Next) + dns_add_serv_s_internal(ctx, pDnsAddr->Address.lpSockaddr); + ret = 0; +freemem: + free(pAddrBuf); +freelib: + FreeLibrary(h_iphlpapi); + return ret; +} + +static int dns_initns_registry(struct dns_ctx *ctx) { + LONG res; + HKEY hk; + DWORD type = REG_EXPAND_SZ | REG_SZ; + DWORD len; + char valBuf[1024]; + +#define REGKEY_WINNT "SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters" +#define REGKEY_WIN9x "SYSTEM\\CurrentControlSet\\Services\\VxD\\MSTCP" + res = RegOpenKeyEx(HKEY_LOCAL_MACHINE, REGKEY_WINNT, 0, KEY_QUERY_VALUE, &hk); + if (res != ERROR_SUCCESS) + res = RegOpenKeyEx(HKEY_LOCAL_MACHINE, REGKEY_WIN9x, + 0, KEY_QUERY_VALUE, &hk); + if (res != ERROR_SUCCESS) + return -1; + len = sizeof(valBuf) - 1; + res = RegQueryValueEx(hk, "NameServer", NULL, &type, valBuf, &len); + if (res != ERROR_SUCCESS || !len || !valBuf[0]) { + len = sizeof(valBuf) - 1; + res = RegQueryValueEx(hk, "DhcpNameServer", NULL, &type, valBuf, &len); + } + RegCloseKey(hk); + if (res != ERROR_SUCCESS || !len || !valBuf[0]) + return -1; + valBuf[len] = '\0'; + /* nameservers are stored as a whitespace-seperate list: + * "192.168.1.1 123.21.32.12" */ + dns_set_serv_internal(ctx, valBuf); + return 0; +} + +static int dns_init_internal(struct dns_ctx *ctx) { + if (dns_initns_iphlpapi(ctx) != 0) + dns_initns_registry(ctx); + /*XXX WIN32: probably good to get default domain and search list too... + * And options. Something is in registry. */ + /*XXX WIN32: maybe environment variables are also useful? */ + return 0; +} + +#else /* !WIN32 */ + +static int dns_init_internal(struct dns_ctx *ctx) { + char *v; + char buf[2049]; /* this buffer is used to hold /etc/resolv.conf */ + + /* read resolv.conf... */ + { int fd = open("/etc/resolv.conf", O_RDONLY); + if (fd >= 0) { + int l = read(fd, buf, sizeof(buf) - 1); + close(fd); + buf[l < 0 ? 0 : l] = '\0'; + } + else + buf[0] = '\0'; + } + if (buf[0]) { /* ...and parse it */ + char *line, *nextline; + line = buf; + do { + nextline = strchr(line, '\n'); + if (nextline) *nextline++ = '\0'; + v = line; + while(*v && !ISSPACE(*v)) ++v; + if (!*v) continue; + *v++ = '\0'; + while(ISSPACE(*v)) ++v; + if (!*v) continue; + if (strcmp(line, "domain") == 0) + dns_set_srch_internal(ctx, strtok(v, space)); + else if (strcmp(line, "search") == 0) + dns_set_srch_internal(ctx, v); + else if (strcmp(line, "nameserver") == 0) + dns_add_serv_internal(ctx, strtok(v, space)); + else if (strcmp(line, "options") == 0) + dns_set_opts_internal(ctx, v); + } while((line = nextline) != NULL); + } + + buf[sizeof(buf)-1] = '\0'; + + /* get list of nameservers from env. vars. */ + if ((v = getenv("NSCACHEIP")) != NULL || + (v = getenv("NAMESERVERS")) != NULL) { + strncpy(buf, v, sizeof(buf) - 1); + dns_set_serv_internal(ctx, buf); + } + /* if $LOCALDOMAIN is set, use it for search list */ + if ((v = getenv("LOCALDOMAIN")) != NULL) { + strncpy(buf, v, sizeof(buf) - 1); + dns_set_srch_internal(ctx, buf); + } + if ((v = getenv("RES_OPTIONS")) != NULL) + dns_set_opts_internal(ctx, v); + + /* if still no search list, use local domain name */ + if (!ctx->dnsc_nsrch && + gethostname(buf, sizeof(buf) - 1) == 0 && + (v = strchr(buf, '.')) != NULL && + *++v != '\0') + dns_add_srch_internal(ctx, v); + + return 0; +} + +#endif /* dns_init_internal() for !WIN32 */ + +int dns_init(int do_open) { + struct dns_ctx *ctx = &dns_defctx; + assert(!CTXINITED(ctx)); + memset(ctx, 0, sizeof(*ctx)); + ctx->dnsc_timeout = 4; + ctx->dnsc_ntries = 3; + ctx->dnsc_ndots = 1; + ctx->dnsc_udpbuf = DNS_EDNS0PACKET; + ctx->dnsc_port = DNS_PORT; + ctx->dnsc_udpsock = -1; + qlist_init(&ctx->dnsc_qactive); + if (dns_init_internal(ctx) != 0) + return -1; + dns_firstid(ctx); + ctx->dnsc_flags |= DNS_INITED; + return do_open ? dns_open(ctx) : 0; +} + +struct dns_ctx *dns_new(const struct dns_ctx *ctx) { + struct dns_ctx *n; + SETCTXINITED(ctx); + dns_assert_ctx(ctx); + n = malloc(sizeof(*n)); + if (!n) + return NULL; + *n = *ctx; + n->dnsc_udpsock = -1; + qlist_init(&n->dnsc_qactive); + n->dnsc_nactive = 0; + n->dnsc_pbuf = NULL; + n->dnsc_qstatus = 0; + n->dnsc_utmfn = NULL; + n->dnsc_utmctx = NULL; + dns_firstid(n); + return n; +} + +void dns_free(struct dns_ctx *ctx) { + struct dns_query *q; + SETCTXINITED(ctx); + dns_assert_ctx(ctx); + dns_drop_utm(ctx); + if (ctx->dnsc_udpsock >= 0) + closesocket(ctx->dnsc_udpsock); + if (ctx->dnsc_pbuf) + free(ctx->dnsc_pbuf); + while((q = qlist_pop(&ctx->dnsc_qactive))) + free(q); + if (ctx != &dns_defctx) + free(ctx); + else + memset(ctx, 0, sizeof(*ctx)); +} + +int dns_open(struct dns_ctx *ctx) { + int sock; + unsigned i; + int port; + union sockaddr_ns *sns; +#if HAVE_INET6 + unsigned have_inet6 = 0; +#endif + + SETCTXINITED(ctx); + assert(!CTXOPEN(ctx)); + + port = htons(ctx->dnsc_port); + /* ensure we have at least one server */ + if (!ctx->dnsc_nserv) { + sns = ctx->dnsc_serv; + sns->sin.sin_family = AF_INET; + sns->sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK); + ctx->dnsc_nserv = 1; + } + + for (i = 0; i < ctx->dnsc_nserv; ++i) { + sns = &ctx->dnsc_serv[i]; + /* set port for each sockaddr */ +#if HAVE_INET6 + if (sns->sa.sa_family == AF_INET6) { + if (!sns->sin6.sin6_port) sns->sin6.sin6_port = port; + ++have_inet6; + } + else +#endif + { + assert(sns->sa.sa_family == AF_INET); + if (!sns->sin.sin_port) sns->sin.sin_port = port; + } + } + +#if !HAVE_INET6 + ctx->dnsc_salen = sizeof(struct sockaddr_in); +#else + if (have_inet6 && have_inet6 < ctx->dnsc_nserv) { + /* convert all IPv4 addresses to IPv6 V4MAPPED */ + struct sockaddr_in6 sin6; + memset(&sin6, 0, sizeof(sin6)); + sin6.sin6_family = AF_INET6; + /* V4MAPPED: ::ffff:1.2.3.4 */ + sin6.sin6_addr.s6_addr[10] = 0xff; + sin6.sin6_addr.s6_addr[11] = 0xff; + for(i = 0; i < ctx->dnsc_nserv; ++i) { + sns = &ctx->dnsc_serv[i]; + if (sns->sa.sa_family == AF_INET) { + sin6.sin6_port = sns->sin.sin_port; + ((struct in_addr*)&sin6.sin6_addr)[3] = sns->sin.sin_addr; + sns->sin6 = sin6; + } + } + } + + ctx->dnsc_salen = have_inet6 ? + sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in); + + if (have_inet6) + sock = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP); + else +#endif /* HAVE_INET6 */ + sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP); + + if (sock < 0) { + ctx->dnsc_qstatus = DNS_E_TEMPFAIL; + return -1; + } +#ifdef WIN32 + { unsigned long on = 1; + if (ioctlsocket(sock, FIONBIO, &on) == SOCKET_ERROR) { + closesocket(sock); + ctx->dnsc_qstatus = DNS_E_TEMPFAIL; + return -1; + } + } +#else /* !WIN32 */ + if (fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_NONBLOCK) < 0 || + fcntl(sock, F_SETFD, FD_CLOEXEC) < 0) { + closesocket(sock); + ctx->dnsc_qstatus = DNS_E_TEMPFAIL; + return -1; + } +#endif /* WIN32 */ + /* allocate the packet buffer */ + if (!(ctx->dnsc_pbuf = malloc(ctx->dnsc_udpbuf))) { + closesocket(sock); + ctx->dnsc_qstatus = DNS_E_NOMEM; + errno = ENOMEM; + return -1; + } + + ctx->dnsc_udpsock = sock; + return sock; +} + +void dns_close(struct dns_ctx *ctx) { + SETCTXINITED(ctx); + if (ctx->dnsc_udpsock < 0) return; + closesocket(ctx->dnsc_udpsock); + ctx->dnsc_udpsock = -1; + free(ctx->dnsc_pbuf); + ctx->dnsc_pbuf = NULL; +} + +int dns_sock(const struct dns_ctx *ctx) { + SETCTXINITED(ctx); + return ctx->dnsc_udpsock; +} + +int dns_active(const struct dns_ctx *ctx) { + SETCTXINITED(ctx); + dns_assert_ctx(ctx); + return ctx->dnsc_nactive; +} + +int dns_status(const struct dns_ctx *ctx) { + SETCTX(ctx); + return ctx->dnsc_qstatus; +} +void dns_setstatus(struct dns_ctx *ctx, int status) { + SETCTX(ctx); + ctx->dnsc_qstatus = status; +} + +/* End the query and return the result to the caller. + */ +static void +dns_end_query(struct dns_ctx *ctx, struct dns_query *q, + int status, void *result) { + dns_query_fn *cbck = q->dnsq_cbck; + void *cbdata = q->dnsq_cbdata; + ctx->dnsc_qstatus = status; + assert((status < 0 && result == 0) || (status >= 0 && result != 0)); + assert(cbck != 0); /*XXX callback may be NULL */ + assert(ctx->dnsc_nactive > 0); + --ctx->dnsc_nactive; + /* force the query to be unconnected */ + /*memset(q, 0, sizeof(*q));*/ +#ifndef NDEBUG + q->dnsq_ctx = NULL; +#endif + free(q); + cbck(ctx, result, cbdata); +} + +#define DNS_DBG(ctx, code, sa, slen, pkt, plen) \ + do { \ + if (ctx->dnsc_udbgfn) \ + ctx->dnsc_udbgfn(code, (sa), slen, pkt, plen, 0, 0); \ + } while(0) +#define DNS_DBGQ(ctx, q, code, sa, slen, pkt, plen) \ + do { \ + if (ctx->dnsc_udbgfn) \ + ctx->dnsc_udbgfn(code, (sa), slen, pkt, plen, q, q->dnsq_cbdata); \ + } while(0) + +/* Try next search, filling in qDN in query. + * Return new qDN len or 0 if no more to search. + * Caller should fill up the rest of the query. + */ +static unsigned dns_next_srch(const struct dns_ctx *ctx, struct dns_query *q) { + unsigned ol = q->dnsq_origdnl - 1; /* origdnl is at least 1 */ + dnsc_t *p = dns_payload(q->dnsq_buf) + ol; + dnscc_t *dn; + int n; + while (q->dnsq_srchi < ctx->dnsc_nsrch) { + dn = ctx->dnsc_srch[q->dnsq_srchi++]; + if (!*dn) { /* root dn */ + if (!(q->dnsq_flags & DNS_ASIS_DONE)) + break; + } + else if ((n = dns_dntodn(dn, p, DNS_MAXDN - ol)) > 0) + return n + ol; + } + if (q->dnsq_flags & DNS_ASIS_DONE) + return 0; + q->dnsq_flags |= DNS_ASIS_DONE; + *p = '\0'; + return ol + 1; +} + +/* find the next server which isn't skipped starting from current. + * return 0 if ok, >0 if ok but we started next cycle, or <0 if + * number of tries exceeded or no more servers. + */ +static int dns_find_serv(const struct dns_ctx *ctx, struct dns_query *q) { + int cycle; + if (q->dnsq_try < ctx->dnsc_ntries) for(cycle = 0;;) { + if (q->dnsq_servi < ctx->dnsc_nserv) { + if (!(q->dnsq_servskip & (1 << q->dnsq_servi))) + return cycle; + ++q->dnsq_servi; + } + else if (cycle || ++q->dnsq_try >= ctx->dnsc_ntries) + break; + else { + cycle = 1; + q->dnsq_servi = 0; + } + } + return -1; +} + +/* send the query out and add it to the active list. */ +static void dns_send(struct dns_ctx *ctx, struct dns_query *q, time_t now) { + int n; + struct dns_query *p; + + /* if we can't send the query, return TEMPFAIL even when searching: + * we can't be sure whenever the name we tried to search exists or not, + * so don't continue searching, or we may find the wrong name. */ + + /* if there's no more servers, fail the query */ + n = dns_find_serv(ctx, q); + if (n < 0) { + dns_end_query(ctx, q, DNS_E_TEMPFAIL, 0); + return; + } + + /* send the query */ + n = 10; + while (sendto(ctx->dnsc_udpsock, q->dnsq_buf, q->dnsq_len, 0, + &ctx->dnsc_serv[q->dnsq_servi].sa, ctx->dnsc_salen) < 0) { + /*XXX just ignore the sendto() error for now and try again. + * In the future, it may be possible to retrieve the error code + * and find which operation/query failed. + *XXX try the next server too? + */ + if (--n) continue; + /* if we can't send the query, fail it. */ + dns_end_query(ctx, q, DNS_E_TEMPFAIL, 0); + return; + } + DNS_DBGQ(ctx, q, 1, + &ctx->dnsc_serv[q->dnsq_servi].sa, sizeof(union sockaddr_ns), + q->dnsq_buf, q->dnsq_len); + q->dnsq_servwait |= 1 << q->dnsq_servi; /* expect reply from this ns */ + + /* advance to the next server, and choose a timeout. + * we will try next server in 1 secound, but start next + * cycle waiting for proper timeout. */ + ++q->dnsq_servi; + n = dns_find_serv(ctx, q) ? ctx->dnsc_timeout << (q->dnsq_try - 1) : 1; + + q->dnsq_deadline = now = now + n; + + /* insert the query to the tail of the list */ + QLIST_FOR_EACH(&ctx->dnsc_qactive, p, prev) + if (p->dnsq_deadline <= now) + break; + qlist_insert_after(q, p); + +} + +static void dns_dummy_cb(struct dns_ctx *ctx, void *result, void *data) { + if (result) free(result); + data = ctx = 0; /* used */ +} + +struct dns_query * +dns_submit_dn(struct dns_ctx *ctx, + dnscc_t *dn, int qcls, int qtyp, int flags, + dns_parse_fn *parse, dns_query_fn *cbck, void *data) { + dnsc_t *p; + unsigned dnl; + struct dns_query *q; + SETCTXOPEN(ctx); + dns_assert_ctx(ctx); + + q = calloc(sizeof(*q), 1); + if (!q) { + ctx->dnsc_qstatus = DNS_E_NOMEM; + return NULL; + } + +#ifndef NDEBUG + q->dnsq_ctx = ctx; +#endif + q->dnsq_parse = parse; + q->dnsq_cbck = cbck ? cbck : dns_dummy_cb; + q->dnsq_cbdata = data; + + flags = (flags | ctx->dnsc_flags) & ~DNS_INTERNAL; + if (!ctx->dnsc_nsrch) q->dnsq_flags |= DNS_NOSRCH; + if (!(flags & DNS_NORD)) q->dnsq_buf[DNS_H_F1] |= DNS_HF1_RD; + if (flags & DNS_AAONLY) q->dnsq_buf[DNS_H_F1] |= DNS_HF1_AA; + q->dnsq_buf[DNS_H_QDCNT2] = 1; + dns_put16(q->dnsq_buf + DNS_H_QID, ctx->dnsc_nextid++); + + q->dnsq_origdnl = dns_dnlen(dn); + assert(q->dnsq_origdnl > 0 && q->dnsq_origdnl <= DNS_MAXDN); + memcpy(dns_payload(q->dnsq_buf), dn, q->dnsq_origdnl); + p = dns_payload(q->dnsq_buf) + q->dnsq_origdnl; + if (flags & DNS_NOSRCH || dns_dnlabels(dn) > ctx->dnsc_ndots) + flags |= DNS_ASIS_DONE; + else if ((dnl = dns_next_srch(ctx, q)) > 0) + p = dns_payload(q->dnsq_buf) + dnl; + else + p[-1] = '\0'; + q->dnsq_flags = flags; + q->dnsq_typ = qtyp; + p = dns_put16(p, qtyp); + q->dnsq_cls = qcls; + p = dns_put16(p, qcls); + if (ctx->dnsc_udpbuf > DNS_MAXPACKET) { + p++; /* empty (root) DN */ + p = dns_put16(p, DNS_T_OPT); + p = dns_put16(p, ctx->dnsc_udpbuf); + p += 2; /* EDNS0 RCODE & VERSION */ + p += 2; /* rest of the TTL field */ + p += 2; /* RDLEN */ + q->dnsq_buf[DNS_H_ARCNT2] = 1; + } + assert(p <= q->dnsq_buf + DNS_QBUF); + q->dnsq_len = p - q->dnsq_buf; + + qlist_add_head(q, &ctx->dnsc_qactive); + ++ctx->dnsc_nactive; + dns_request_utm(ctx, 0); + + return q; +} + +struct dns_query * +dns_submit_p(struct dns_ctx *ctx, + const char *name, int qcls, int qtyp, int flags, + dns_parse_fn *parse, dns_query_fn *cbck, void *data) { + int isabs; + SETCTXOPEN(ctx); + if (dns_ptodn(name, 0, ctx->dnsc_pbuf, DNS_MAXDN, &isabs) <= 0) { + ctx->dnsc_qstatus = DNS_E_BADQUERY; + return NULL; + } + if (isabs) + flags |= DNS_NOSRCH; + return + dns_submit_dn(ctx, ctx->dnsc_pbuf, qcls, qtyp, flags, parse, cbck, data); +} + +/* process readable fd condition. + * To be usable in edge-triggered environment, the routine + * should consume all input so it should loop over. + * Note it isn't really necessary to loop here, because + * an application may perform the loop just fine by it's own, + * but in this case we should return some sensitive result, + * to indicate when to stop calling and error conditions. + * Note also we may encounter all sorts of recvfrom() + * errors which aren't fatal, and at the same time we may + * loop forever if an error IS fatal. + * Current loop/goto looks just terrible... */ +void dns_ioevent(struct dns_ctx *ctx, time_t now) { + int r; + unsigned servi, l; + struct dns_query *q; + dnsc_t *pbuf; + dnscc_t *pend, *pcur; + void *result; + union sockaddr_ns sns; + socklen_t slen; + + SETCTX(ctx); + if (!CTXOPEN(ctx)) + return; + dns_assert_ctx(ctx); + pbuf = ctx->dnsc_pbuf; + + if (!now) now = time(NULL); + +again: + + for(;;) { /* receive the reply */ + dnsc_t dn[DNS_MAXDN]; + + slen = sizeof(sns); + r = recvfrom(ctx->dnsc_udpsock, pbuf, ctx->dnsc_udpbuf, 0, &sns.sa, &slen); + if (r < 0) { + /*XXX just ignore recvfrom() errors for now. + * in the future it may be possible to determine which + * query failed and requeue it. + * Note there may be various error conditions, triggered + * by both local problems and remote problems. It isn't + * quite trivial to determine whenever an error is local + * or remote. On local errors, we should stop, while + * remote errors should be ignored (for now anyway). + */ +#ifdef WIN32 + if (WSAGetLastError() == WSAEWOULDBLOCK) +#else + if (errno == EAGAIN) +#endif + { + dns_request_utm(ctx, now); + return; + } + continue; + } + /* ignore replies from wrong server */ +#if HAVE_INET6 + if (sns.sa.sa_family == AF_INET6 && slen >= sizeof(sns.sin6)) { + for (servi = 0; servi < ctx->dnsc_nserv; ++servi) + if (ctx->dnsc_serv[servi].sin6.sin6_port == sns.sin6.sin6_port && + memcmp(&ctx->dnsc_serv[servi].sin6.sin6_addr, + &sns.sin6.sin6_addr, sizeof(sns.sin6.sin6_addr)) == 0) + break; + } + else +#endif + if (sns.sa.sa_family == AF_INET && slen >= sizeof(sns.sin)) { + for (servi = 0; servi < ctx->dnsc_nserv; ++servi) + if (ctx->dnsc_serv[servi].sin.sin_addr.s_addr == sns.sin.sin_addr.s_addr && + ctx->dnsc_serv[servi].sin.sin_port == sns.sin.sin_port) + break; + } + else { + DNS_DBG(ctx, -1, &sns.sa, slen, pbuf, r); + continue; + } + if (servi >= ctx->dnsc_nserv) { + DNS_DBG(ctx, -2, &sns.sa, slen, pbuf, r); + continue; + } + + pend = pbuf + r; + pcur = dns_payload(pbuf); + if (pcur >= pend || dns_numqd(pbuf) != 1 || dns_opcode(pbuf) != 0 || + dns_getdn(pbuf, &pcur, pend, dn, sizeof(dn)) < 0 || + pcur + 4 > pend) { + /*XXX ignore non-query replies and replies with numqd!=1? */ + DNS_DBG(ctx, -3, &sns.sa, slen, pbuf, r); + continue; + } + + /* truncation bit (TC). Ooh, we don't handle TCP (yet?), + * but we do handle larger UDP sizes. + * Note that e.g. djbdns will only send header if resp. + * does not fit, not whatever is fit in 512 bytes. */ + if (dns_tc(pbuf)) { + DNS_DBG(ctx, -4, &sns.sa, slen, pbuf, r); + continue; /* just ignore response for now.. any hope? */ + } + + /* find the request for this reply in active queue + * Note we pick any request, even queued for another + * server - in case first server replies a bit later + * than we expected. */ + for (q = QLIST_FIRST(&ctx->dnsc_qactive, next);; q = QLIST_NEXT(q, next)) { + if (QLIST_ISLAST(&ctx->dnsc_qactive, q)) { + /* no more requests: old reply? */ + DNS_DBG(ctx, -5, &sns.sa, slen, pbuf, r); + goto again; + } + /* ignore replies that has not been sent to this server. + * Note dnsq_servi is the *next* server to try. */ + if (!q->dnsq_try && q->dnsq_servi <= servi) + continue; + /*XXX ignore replies from servers we're ignoring? o/ + if (q->dnsq_servskip & (1 << servi)) + continue; */ + /* check qID */ + if (q->dnsq_buf[DNS_H_QID1] != pbuf[DNS_H_QID1] || + q->dnsq_buf[DNS_H_QID2] != pbuf[DNS_H_QID2]) + continue; + /* check qDN, qCLS and qTYP */ + if (!(l = dns_dnequal(dn, dns_payload(q->dnsq_buf))) || + memcmp(pcur, dns_payload(q->dnsq_buf) + l, 4) != 0) + continue; + /* ok, this is expected reply with matching query. */ + break; + } + + break; + + } + + DNS_DBGQ(ctx, q, 0, &sns.sa, slen, pbuf, r); + + /* we got a reply for our query */ + q->dnsq_servwait &= ~(1 << servi); /* don't expect reply from this serv */ + + /* process the RCODE */ + switch(dns_rcode(pbuf)) { + + case DNS_R_NOERROR: + qlist_remove(q); + if (!dns_numan(pbuf)) { /* no data of requested type */ + q->dnsq_flags |= DNS_SEEN_NODATA; + r = DNS_E_NODATA; + break; + } + /* the only case where we may succeed */ + if (q->dnsq_parse) { + r = q->dnsq_parse(dns_payload(q->dnsq_buf), pbuf, pcur, pend, &result); + if (r < 0) + result = NULL; + } + else if ((result = malloc(r)) != NULL) + memcpy(result, pbuf, r); + else + r = DNS_E_NOMEM; + /* (maybe) successeful answer (modulo nomem and parsing probs) */ + /* note we pass DNS_E_NODATA here */ + dns_end_query(ctx, q, r, result); + goto again; + + case DNS_R_NXDOMAIN: + qlist_remove(q); + r = DNS_E_NXDOMAIN; + break; + + case DNS_R_SERVFAIL: + q->dnsq_flags |= DNS_SEEN_FAIL; + case DNS_R_NOTIMPL: + case DNS_R_REFUSED: + /* for these rcodes, advance this request + * to the next server and reschedule */ + default: /* unknown rcode? hmmm... */ + /* try next server */ + q->dnsq_servskip |= 1 << servi; /* don't retry this server */ + if (!q->dnsq_servwait) { + qlist_remove(q); + dns_send(ctx, q, now); + } + else { + /* else this is the only place where q will be left unconnected + * if we will move qlist_remove() before the switch{}. */ + } + goto again; + + } + + /* here we have either NODATA or NXDOMAIN */ + if (!(q->dnsq_flags & DNS_NOSRCH)) { + /* try next element from search list */ + unsigned sl; + + l = dns_dnlen(dns_payload(q->dnsq_buf)) + DNS_HSIZE; /* past qDN */ + /* save qcls, qtyp and EDNS0 stuff (of len sl) in pbuf */ + sl = q->dnsq_len - l; + memcpy(pbuf, q->dnsq_buf + l, sl); + /* try next search list */ + l = dns_next_srch(ctx, q); + if (l) { /* something else to try, of len l */ + l += DNS_HSIZE; + memcpy(q->dnsq_buf + l, pbuf, sl); + q->dnsq_len = l + sl; + q->dnsq_try = 0; q->dnsq_servi = 0; + q->dnsq_servwait = q->dnsq_servskip = 0; + dns_send(ctx, q, now); + goto again; + } + /* else we have nothing more to search, end the query. */ + if (q->dnsq_flags & DNS_SEEN_FAIL) + /* at least one server/query failed, fail the query */ + r = DNS_E_TEMPFAIL; + else if (q->dnsq_flags & DNS_SEEN_NODATA) + /* for one domain we have seen NODATA, return it */ + r = DNS_E_NODATA; + else /* else all should be NXDOMAINs */ + r = DNS_E_NXDOMAIN; + } + + dns_end_query(ctx, q, r, 0); + goto again; +} + +/* handle all timeouts */ +int dns_timeouts(struct dns_ctx *ctx, int maxwait, time_t now) { + struct dns_query *q; + int w; + SETCTX(ctx); + dns_assert_ctx(ctx); + if (!now) now = time(NULL); + while((q = qlist_first(&ctx->dnsc_qactive)) && q->dnsq_deadline <= now) { + qlist_remove(q); + dns_send(ctx, q, now); + } + dns_request_utm(ctx, now); + if (!q) + return maxwait; + w = q->dnsq_deadline - now; + return maxwait < 0 || maxwait > w ? w : maxwait; +} + +struct dns_resolve_data { + int dnsrd_done; + void *dnsrd_result; +}; + +static void dns_resolve_cb(struct dns_ctx *ctx, void *result, void *data) { + struct dns_resolve_data *d = data; + d->dnsrd_result = result; + d->dnsrd_done = 1; + ctx = ctx; +} + +void *dns_resolve(struct dns_ctx *ctx, struct dns_query *q) { + time_t now; +#ifdef HAVE_POLL + struct pollfd pfd; +#else + fd_set rfd; + struct timeval tv; +#endif + struct dns_resolve_data d; + int n; + SETCTXOPEN(ctx); + + if (!q) + return NULL; + + assert(ctx == q->dnsq_ctx); + dns_assert_ctx(ctx); + /* do not allow re-resolving syncronous queries */ + assert(q->dnsq_cbck != dns_resolve_cb && "can't resolve syncronous query"); + if (q->dnsq_cbck == dns_resolve_cb) { + ctx->dnsc_qstatus = DNS_E_BADQUERY; + return NULL; + } + q->dnsq_cbck = dns_resolve_cb; + q->dnsq_cbdata = &d; + d.dnsrd_done = 0; + +#ifdef HAVE_POLL + pfd.fd = ctx->dnsc_udpsock; + pfd.events = POLLIN; +#else + FD_ZERO(&rfd); +#endif + + now = time(NULL); + while(!d.dnsrd_done && (n = dns_timeouts(ctx, -1, now)) >= 0) { +#ifdef HAVE_POLL + n = poll(&pfd, 1, n * 1000); +#else + tv.tv_sec = n; + tv.tv_usec = 0; + FD_SET(ctx->dnsc_udpsock, &rfd); + n = select(ctx->dnsc_udpsock + 1, &rfd, NULL, NULL, &tv); +#endif + now = time(NULL); + if (n > 0) + dns_ioevent(ctx, now); + } + + return d.dnsrd_result; +} + +void *dns_resolve_dn(struct dns_ctx *ctx, + dnscc_t *dn, int qcls, int qtyp, int flags, + dns_parse_fn *parse) { + return + dns_resolve(ctx, + dns_submit_dn(ctx, dn, qcls, qtyp, flags, parse, NULL, NULL)); +} + +void *dns_resolve_p(struct dns_ctx *ctx, + const char *name, int qcls, int qtyp, int flags, + dns_parse_fn *parse) { + return + dns_resolve(ctx, + dns_submit_p(ctx, name, qcls, qtyp, flags, parse, NULL, NULL)); +} + +int dns_cancel(struct dns_ctx *ctx, struct dns_query *q) { + SETCTX(ctx); + dns_assert_ctx(ctx); + assert(q->dnsq_ctx == ctx); + /* do not allow cancelling syncronous queries */ + assert(q->dnsq_cbck != dns_resolve_cb && "can't cancel syncronous query"); + if (q->dnsq_cbck == dns_resolve_cb) + return (ctx->dnsc_qstatus = DNS_E_BADQUERY); + qlist_remove(q); + --ctx->dnsc_nactive; + dns_request_utm(ctx, 0); + return 0; +} + diff --git a/libs/udns/udns_rr_a.c b/libs/udns/udns_rr_a.c new file mode 100644 index 0000000000..2266252614 --- /dev/null +++ b/libs/udns/udns_rr_a.c @@ -0,0 +1,124 @@ +/* $Id: udns_rr_a.c,v 1.14 2005/04/20 06:44:34 mjt Exp $ + parse/query A/AAAA IN records + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#ifdef WIN32 +# include /* includes */ +# include /* needed for struct in6_addr */ +#else +# include +# include +#endif +#include "udns.h" + +/* here, we use common routine to parse both IPv4 and IPv6 addresses. + */ + +/* this structure should match dns_rr_a[46] */ +struct dns_rr_a { + dns_rr_common(dnsa); + unsigned char *dnsa_addr; +}; + +static int +dns_parse_a(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result, unsigned dsize) { + struct dns_rr_a *ret; + struct dns_parse p; + struct dns_rr rr; + int r; + + /* first, validate and count number of addresses */ + dns_initparse(&p, qdn, pkt, cur, end); + while((r = dns_nextrr(&p, &rr)) > 0) + if (rr.dnsrr_dsz != dsize) + return DNS_E_PROTOCOL; + if (r < 0) + return DNS_E_PROTOCOL; + else if (!p.dnsp_nrr) + return DNS_E_NODATA; + + ret = malloc(sizeof(*ret) + dsize * p.dnsp_nrr + dns_stdrr_size(&p)); + if (!ret) + return DNS_E_NOMEM; + + ret->dnsa_nrr = p.dnsp_nrr; + ret->dnsa_addr = (unsigned char*)(ret+1); + + /* copy the RRs */ + for (dns_rewind(&p, qdn), r = 0; dns_nextrr(&p, &rr); ++r) + memcpy(ret->dnsa_addr + dsize * r, rr.dnsrr_dptr, dsize); + + dns_stdrr_finish((struct dns_rr_null *)ret, + (char *)(ret->dnsa_addr + dsize * p.dnsp_nrr), &p); + *result = ret; + return 0; +} + +int +dns_parse_a4(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { + assert(sizeof(struct in_addr) == 4); + assert(dns_get16(cur+2) == DNS_C_IN && dns_get16(cur+0) == DNS_T_A); + return dns_parse_a(qdn, pkt, cur, end, result, 4); +} + +struct dns_query * +dns_submit_a4(struct dns_ctx *ctx, const char *name, int flags, + dns_query_a4_fn *cbck, void *data) { + return + dns_submit_p(ctx, name, DNS_C_IN, DNS_T_A, flags, + dns_parse_a4, (dns_query_fn*)cbck, data); +} + +struct dns_rr_a4 * +dns_resolve_a4(struct dns_ctx *ctx, const char *name, int flags) { + return (struct dns_rr_a4 *) + dns_resolve_p(ctx, name, DNS_C_IN, DNS_T_A, flags, dns_parse_a4); +} + +int +dns_parse_a6(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { +#ifdef AF_INET6 + assert(sizeof(struct in6_addr) == 16); +#endif + assert(dns_get16(cur+2) == DNS_C_IN && dns_get16(cur+0) == DNS_T_AAAA); + return dns_parse_a(qdn, pkt, cur, end, result, 16); +} + +struct dns_query * +dns_submit_a6(struct dns_ctx *ctx, const char *name, int flags, + dns_query_a6_fn *cbck, void *data) { + return + dns_submit_p(ctx, name, DNS_C_IN, DNS_T_AAAA, flags, + dns_parse_a6, (dns_query_fn*)cbck, data); +} + +struct dns_rr_a6 * +dns_resolve_a6(struct dns_ctx *ctx, const char *name, int flags) { + return (struct dns_rr_a6 *) + dns_resolve_p(ctx, name, DNS_C_IN, DNS_T_AAAA, flags, dns_parse_a6); +} diff --git a/libs/udns/udns_rr_mx.c b/libs/udns/udns_rr_mx.c new file mode 100644 index 0000000000..cf8348354f --- /dev/null +++ b/libs/udns/udns_rr_mx.c @@ -0,0 +1,91 @@ +/* $Id: udns_rr_mx.c,v 1.13 2005/04/20 06:44:34 mjt Exp $ + parse/query MX IN records + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#include "udns.h" + +int +dns_parse_mx(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { + struct dns_rr_mx *ret; + struct dns_parse p; + struct dns_rr rr; + int r, l; + char *sp; + dnsc_t mx[DNS_MAXDN]; + + assert(dns_get16(cur+2) == DNS_C_IN && dns_get16(cur+0) == DNS_T_MX); + + /* first, validate the answer and count size of the result */ + l = 0; + dns_initparse(&p, qdn, pkt, cur, end); + while((r = dns_nextrr(&p, &rr)) > 0) { + cur = rr.dnsrr_dptr + 2; + r = dns_getdn(pkt, &cur, end, mx, sizeof(mx)); + if (r <= 0 || cur != rr.dnsrr_dend) + return DNS_E_PROTOCOL; + l += dns_dntop_size(mx); + } + if (r < 0) + return DNS_E_PROTOCOL; + if (!p.dnsp_nrr) + return DNS_E_NODATA; + + /* next, allocate and set up result */ + l += dns_stdrr_size(&p); + ret = malloc(sizeof(*ret) + sizeof(struct dns_mx) * p.dnsp_nrr + l); + if (!ret) + return DNS_E_NOMEM; + ret->dnsmx_nrr = p.dnsp_nrr; + ret->dnsmx_mx = (struct dns_mx *)(ret+1); + + /* and 3rd, fill in result, finally */ + sp = (char*)(ret->dnsmx_mx + p.dnsp_nrr); + for (dns_rewind(&p, qdn), r = 0; dns_nextrr(&p, &rr); ++r) { + ret->dnsmx_mx[r].name = sp; + cur = rr.dnsrr_dptr; + ret->dnsmx_mx[r].priority = dns_get16(cur); + cur += 2; + dns_getdn(pkt, &cur, end, mx, sizeof(mx)); + sp += dns_dntop(mx, sp, DNS_MAXNAME); + } + dns_stdrr_finish((struct dns_rr_null *)ret, sp, &p); + *result = ret; + return 0; +} + +struct dns_query * +dns_submit_mx(struct dns_ctx *ctx, const char *name, int flags, + dns_query_mx_fn *cbck, void *data) { + return + dns_submit_p(ctx, name, DNS_C_IN, DNS_T_MX, flags, + dns_parse_mx, (dns_query_fn *)cbck, data); +} + +struct dns_rr_mx * +dns_resolve_mx(struct dns_ctx *ctx, const char *name, int flags) { + return (struct dns_rr_mx *) + dns_resolve_p(ctx, name, DNS_C_IN, DNS_T_MX, flags, dns_parse_mx); +} diff --git a/libs/udns/udns_rr_naptr.c b/libs/udns/udns_rr_naptr.c new file mode 100644 index 0000000000..ec4f514601 --- /dev/null +++ b/libs/udns/udns_rr_naptr.c @@ -0,0 +1,128 @@ +/* $Id: udns_rr_naptr.c,v 1.1 2006/11/28 22:58:04 mjt Exp $ + parse/query NAPTR IN records + + Copyright (C) 2005 Michael Tokarev + Copyright (C) 2006 Mikael Magnusson + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#include "udns.h" + +/* Get a single string for NAPTR record, pretty much like a DN label. + * String length is in first byte in *cur, so it can't be >255. + */ +static int dns_getstr(dnscc_t **cur, dnscc_t *ep, char *buf) +{ + unsigned l; + dnscc_t *cp = *cur; + + l = *cp++; + if (cp + l > ep) + return DNS_E_PROTOCOL; + if (buf) { + memcpy(buf, cp, l); + buf[l] = '\0'; + } + cp += l; + + *cur = cp; + return l + 1; +} + +int +dns_parse_naptr(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { + struct dns_rr_naptr *ret; + struct dns_parse p; + struct dns_rr rr; + int r, l; + char *sp; + dnsc_t dn[DNS_MAXDN]; + + assert(dns_get16(cur+2) == DNS_C_IN && dns_get16(cur+0) == DNS_T_NAPTR); + + /* first, validate the answer and count size of the result */ + l = 0; + dns_initparse(&p, qdn, pkt, cur, end); + while((r = dns_nextrr(&p, &rr)) > 0) { + int i; + dnscc_t *ep = rr.dnsrr_dend; + + /* first 4 bytes: order & preference */ + cur = rr.dnsrr_dptr + 4; + + /* flags, services and regexp */ + for (i = 0; i < 3; i++) { + r = dns_getstr(&cur, ep, NULL); + if (r < 0) + return r; + l += r; + } + /* replacement */ + r = dns_getdn(pkt, &cur, end, dn, sizeof(dn)); + if (r <= 0 || cur != rr.dnsrr_dend) + return DNS_E_PROTOCOL; + l += dns_dntop_size(dn); + } + if (r < 0) + return DNS_E_PROTOCOL; + if (!p.dnsp_nrr) + return DNS_E_NODATA; + + /* next, allocate and set up result */ + l += dns_stdrr_size(&p); + ret = malloc(sizeof(*ret) + sizeof(struct dns_naptr) * p.dnsp_nrr + l); + if (!ret) + return DNS_E_NOMEM; + ret->dnsnaptr_nrr = p.dnsp_nrr; + ret->dnsnaptr_naptr = (struct dns_naptr *)(ret+1); + + /* and 3rd, fill in result, finally */ + sp = (char*)(&ret->dnsnaptr_naptr[p.dnsp_nrr]); + for (dns_rewind(&p, qdn), r = 0; dns_nextrr(&p, &rr); ++r) { + cur = rr.dnsrr_dptr; + ret->dnsnaptr_naptr[r].order = dns_get16(cur); cur += 2; + ret->dnsnaptr_naptr[r].preference = dns_get16(cur); cur += 2; + sp += dns_getstr(&cur, end, (ret->dnsnaptr_naptr[r].flags = sp)); + sp += dns_getstr(&cur, end, (ret->dnsnaptr_naptr[r].service = sp)); + sp += dns_getstr(&cur, end, (ret->dnsnaptr_naptr[r].regexp = sp)); + dns_getdn(pkt, &cur, end, dn, sizeof(dn)); + sp += dns_dntop(dn, (ret->dnsnaptr_naptr[r].replacement = sp), DNS_MAXNAME); + } + dns_stdrr_finish((struct dns_rr_null *)ret, sp, &p); + *result = ret; + return 0; +} + +struct dns_query * +dns_submit_naptr(struct dns_ctx *ctx, const char *name, int flags, + dns_query_naptr_fn *cbck, void *data) { + return + dns_submit_p(ctx, name, DNS_C_IN, DNS_T_NAPTR, flags, + dns_parse_naptr, (dns_query_fn *)cbck, data); +} + +struct dns_rr_naptr * +dns_resolve_naptr(struct dns_ctx *ctx, const char *name, int flags) { + return (struct dns_rr_naptr *) + dns_resolve_p(ctx, name, DNS_C_IN, DNS_T_NAPTR, flags, dns_parse_naptr); +} diff --git a/libs/udns/udns_rr_ptr.c b/libs/udns/udns_rr_ptr.c new file mode 100644 index 0000000000..410af656a5 --- /dev/null +++ b/libs/udns/udns_rr_ptr.c @@ -0,0 +1,109 @@ +/* $Id: udns_rr_ptr.c,v 1.15 2005/09/12 11:21:06 mjt Exp $ + parse/query PTR records + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include "udns.h" + +int +dns_parse_ptr(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { + struct dns_rr_ptr *ret; + struct dns_parse p; + struct dns_rr rr; + int r, l, c; + char *sp; + dnsc_t ptr[DNS_MAXDN]; + + assert(dns_get16(cur+2) == DNS_C_IN && dns_get16(cur+0) == DNS_T_PTR); + + /* first, validate the answer and count size of the result */ + l = c = 0; + dns_initparse(&p, qdn, pkt, cur, end); + while((r = dns_nextrr(&p, &rr)) > 0) { + cur = rr.dnsrr_dptr; + r = dns_getdn(pkt, &cur, end, ptr, sizeof(ptr)); + if (r <= 0 || cur != rr.dnsrr_dend) + return DNS_E_PROTOCOL; + l += dns_dntop_size(ptr); + ++c; + } + if (r < 0) + return DNS_E_PROTOCOL; + if (!c) + return DNS_E_NODATA; + + /* next, allocate and set up result */ + ret = malloc(sizeof(*ret) + sizeof(char **) * c + l + dns_stdrr_size(&p)); + if (!ret) + return DNS_E_NOMEM; + ret->dnsptr_nrr = c; + ret->dnsptr_ptr = (char **)(ret+1); + + /* and 3rd, fill in result, finally */ + sp = (char*)(ret->dnsptr_ptr + c); + c = 0; + dns_rewind(&p, qdn); + while((r = dns_nextrr(&p, &rr)) > 0) { + ret->dnsptr_ptr[c] = sp; + cur = rr.dnsrr_dptr; + dns_getdn(pkt, &cur, end, ptr, sizeof(ptr)); + sp += dns_dntop(ptr, sp, DNS_MAXNAME); + ++c; + } + dns_stdrr_finish((struct dns_rr_null *)ret, sp, &p); + *result = ret; + return 0; +} + +struct dns_query * +dns_submit_a4ptr(struct dns_ctx *ctx, const struct in_addr *addr, + dns_query_ptr_fn *cbck, void *data) { + dnsc_t dn[DNS_A4RSIZE]; + dns_a4todn(addr, 0, dn, sizeof(dn)); + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_PTR, DNS_NOSRCH, + dns_parse_ptr, (dns_query_fn *)cbck, data); +} + +struct dns_rr_ptr * +dns_resolve_a4ptr(struct dns_ctx *ctx, const struct in_addr *addr) { + return (struct dns_rr_ptr *) + dns_resolve(ctx, dns_submit_a4ptr(ctx, addr, NULL, NULL)); +} + +struct dns_query * +dns_submit_a6ptr(struct dns_ctx *ctx, const struct in6_addr *addr, + dns_query_ptr_fn *cbck, void *data) { + dnsc_t dn[DNS_A6RSIZE]; + dns_a6todn(addr, 0, dn, sizeof(dn)); + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_PTR, DNS_NOSRCH, + dns_parse_ptr, (dns_query_fn *)cbck, data); +} + +struct dns_rr_ptr * +dns_resolve_a6ptr(struct dns_ctx *ctx, const struct in6_addr *addr) { + return (struct dns_rr_ptr *) + dns_resolve(ctx, dns_submit_a6ptr(ctx, addr, NULL, NULL)); +} diff --git a/libs/udns/udns_rr_srv.c b/libs/udns/udns_rr_srv.c new file mode 100644 index 0000000000..56bbbf7f78 --- /dev/null +++ b/libs/udns/udns_rr_srv.c @@ -0,0 +1,154 @@ +/* $Id: udns_rr_srv.c,v 1.2 2005/09/12 12:26:22 mjt Exp $ + parse/query SRV IN (rfc2782) records + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + Copyright 2005 Thadeu Lima de Souza Cascardo + + 2005-09-11: + Changed MX parser file into a SRV parser file + + */ + +#include +#include +#include +#include "udns.h" + +int +dns_parse_srv(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { + struct dns_rr_srv *ret; + struct dns_parse p; + struct dns_rr rr; + int r, l; + char *sp; + dnsc_t srv[DNS_MAXDN]; + + assert(dns_get16(cur+2) == DNS_C_IN && dns_get16(cur+0) == DNS_T_SRV); + + /* first, validate the answer and count size of the result */ + l = 0; + dns_initparse(&p, qdn, pkt, cur, end); + while((r = dns_nextrr(&p, &rr)) > 0) { + cur = rr.dnsrr_dptr + 6; + r = dns_getdn(pkt, &cur, end, srv, sizeof(srv)); + if (r <= 0 || cur != rr.dnsrr_dend) + return DNS_E_PROTOCOL; + l += dns_dntop_size(srv); + } + if (r < 0) + return DNS_E_PROTOCOL; + if (!p.dnsp_nrr) + return DNS_E_NODATA; + + /* next, allocate and set up result */ + l += dns_stdrr_size(&p); + ret = malloc(sizeof(*ret) + sizeof(struct dns_srv) * p.dnsp_nrr + l); + if (!ret) + return DNS_E_NOMEM; + ret->dnssrv_nrr = p.dnsp_nrr; + ret->dnssrv_srv = (struct dns_srv *)(ret+1); + + /* and 3rd, fill in result, finally */ + sp = (char*)(ret->dnssrv_srv + p.dnsp_nrr); + for (dns_rewind(&p, qdn), r = 0; dns_nextrr(&p, &rr); ++r) { + ret->dnssrv_srv[r].name = sp; + cur = rr.dnsrr_dptr; + ret->dnssrv_srv[r].priority = dns_get16(cur); + ret->dnssrv_srv[r].weight = dns_get16(cur+2); + ret->dnssrv_srv[r].port = dns_get16(cur+4); + cur += 6; + dns_getdn(pkt, &cur, end, srv, sizeof(srv)); + sp += dns_dntop(srv, sp, DNS_MAXNAME); + } + dns_stdrr_finish((struct dns_rr_null *)ret, sp, &p); + *result = ret; + return 0; +} + +/* Add a single service or proto name prepending an undescore (_), + * according to rfc2782 rules. + * Return 0 or the label length. + * Routing assumes dn holds enouth space for a single DN label. */ +static unsigned add_sname(dnsc_t *dn, const char *sn) { + unsigned l; + l = dns_ptodn(sn, 0, dn + 1, DNS_MAXLABEL-1, NULL); + if (l <= 1 || l - 2 != dn[1]) + /* Should we really check if sn is exactly one label? Do we care? */ + return 0; + dn[0] = l - 1; + dn[1] = '_'; + return l; +} + +/* Construct a domain name for SRV query from the given name, service and + * protocol (service may be NULL in which case protocol isn't used). + * Return negative value on error (malformed query), + * or addition query flag(s) to use. + */ +static int +build_srv_dn(dnsc_t *dn, const char *name, const char *srv, const char *proto) +{ + unsigned p = 0, l; + int isabs; + if (srv) { + l = add_sname(dn + p, srv); + if (!l) + return -1; + p += l; + l = add_sname(dn + p, proto); + if (!l) + return -1; + p += l; + } + l = dns_ptodn(name, 0, dn + p, DNS_MAXDN - p, &isabs); + if (!l) + return -1; + return isabs ? DNS_NOSRCH : 0; +} + +struct dns_query * +dns_submit_srv(struct dns_ctx *ctx, + const char *name, const char *srv, const char *proto, + int flags, dns_query_srv_fn *cbck, void *data) { + dnsc_t dn[DNS_MAXDN]; + int r = build_srv_dn(dn, name, srv, proto); + if (r < 0) { + dns_setstatus (ctx, DNS_E_BADQUERY); + return NULL; + } + return + dns_submit_dn(ctx, dn, DNS_C_IN, DNS_T_SRV, flags | r, + dns_parse_srv, (dns_query_fn *)cbck, data); +} + +struct dns_rr_srv * +dns_resolve_srv(struct dns_ctx *ctx, + const char *name, const char *srv, const char *proto, int flags) +{ + dnsc_t dn[DNS_MAXDN]; + int r = build_srv_dn(dn, name, srv, proto); + if (r < 0) { + dns_setstatus(ctx, DNS_E_BADQUERY); + return NULL; + } + return (struct dns_rr_srv *) + dns_resolve_dn(ctx, dn, DNS_C_IN, DNS_T_SRV, flags | r, dns_parse_srv); +} diff --git a/libs/udns/udns_rr_txt.c b/libs/udns/udns_rr_txt.c new file mode 100644 index 0000000000..ecc71f06ed --- /dev/null +++ b/libs/udns/udns_rr_txt.c @@ -0,0 +1,98 @@ +/* $Id: udns_rr_txt.c,v 1.15 2006/11/28 22:45:20 mjt Exp $ + parse/query TXT records + + Copyright (C) 2005 Michael Tokarev + This file is part of UDNS library, an async DNS stub resolver. + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library, in file named COPYING.LGPL; if not, + write to the Free Software Foundation, Inc., 59 Temple Place, + Suite 330, Boston, MA 02111-1307 USA + + */ + +#include +#include +#include +#include "udns.h" + +int +dns_parse_txt(dnscc_t *qdn, dnscc_t *pkt, dnscc_t *cur, dnscc_t *end, + void **result) { + struct dns_rr_txt *ret; + struct dns_parse p; + struct dns_rr rr; + int r, l; + dnsc_t *sp; + dnscc_t *cp, *ep; + + assert(dns_get16(cur+0) == DNS_T_TXT); + + /* first, validate the answer and count size of the result */ + l = 0; + dns_initparse(&p, qdn, pkt, cur, end); + while((r = dns_nextrr(&p, &rr)) > 0) { + cp = rr.dnsrr_dptr; ep = rr.dnsrr_dend; + while(cp < ep) { + r = *cp++; + if (cp + r > ep) + return DNS_E_PROTOCOL; + l += r; + cp += r; + } + } + if (r < 0) + return DNS_E_PROTOCOL; + if (!p.dnsp_nrr) + return DNS_E_NODATA; + + /* next, allocate and set up result */ + l += (sizeof(struct dns_txt) + 1) * p.dnsp_nrr + dns_stdrr_size(&p); + ret = malloc(sizeof(*ret) + l); + if (!ret) + return DNS_E_NOMEM; + ret->dnstxt_nrr = p.dnsp_nrr; + ret->dnstxt_txt = (struct dns_txt *)(ret+1); + + /* and 3rd, fill in result, finally */ + sp = (dnsc_t*)(ret->dnstxt_txt + p.dnsp_nrr); + for(dns_rewind(&p, qdn), r = 0; dns_nextrr(&p, &rr) > 0; ++r) { + ret->dnstxt_txt[r].txt = sp; + cp = rr.dnsrr_dptr; ep = rr.dnsrr_dend; + while(cp < ep) { + l = *cp++; + memcpy(sp, cp, l); + sp += l; + cp += l; + } + ret->dnstxt_txt[r].len = sp - ret->dnstxt_txt[r].txt; + *sp++ = '\0'; + } + dns_stdrr_finish((struct dns_rr_null *)ret, (char*)sp, &p); + *result = ret; + return 0; +} + +struct dns_query * +dns_submit_txt(struct dns_ctx *ctx, const char *name, int qcls, int flags, + dns_query_txt_fn *cbck, void *data) { + return + dns_submit_p(ctx, name, qcls, DNS_T_TXT, flags, + dns_parse_txt, (dns_query_fn *)cbck, data); +} + +struct dns_rr_txt * +dns_resolve_txt(struct dns_ctx *ctx, const char *name, int qcls, int flags) { + return (struct dns_rr_txt *) + dns_resolve_p(ctx, name, qcls, DNS_T_TXT, flags, dns_parse_txt); +} diff --git a/src/include/switch_types.h b/src/include/switch_types.h index 06e803b1f4..1b08cbe5a8 100644 --- a/src/include/switch_types.h +++ b/src/include/switch_types.h @@ -86,6 +86,8 @@ SWITCH_BEGIN_EXTERN_C #define SWITCH_LOCAL_MEDIA_PORT_VARIABLE "_local_media_port_" #define SWITCH_REMOTE_MEDIA_IP_VARIABLE "_remote_media_ip_" #define SWITCH_REMOTE_MEDIA_PORT_VARIABLE "_remote_media_port_" +#define SWITCH_HANGUP_AFTER_BRIDGE_VARIABLE "hangup_after_bridge" + #define SWITCH_SPEECH_KEY "_speech_" #define SWITCH_UUID_BRIDGE "_uuid_bridge_" #define SWITCH_BITS_PER_BYTE 8 diff --git a/src/include/switch_utils.h b/src/include/switch_utils.h index 2ff270eb8f..8886eaa552 100644 --- a/src/include/switch_utils.h +++ b/src/include/switch_utils.h @@ -39,6 +39,7 @@ #define SWITCH_UTILS_H #include +#include SWITCH_BEGIN_EXTERN_C @@ -231,8 +232,15 @@ SWITCH_DECLARE(int) switch_socket_waitfor(switch_pollfd_t *poll, int ms); */ SWITCH_DECLARE(char *) switch_cut_path(char *in); +#define switch_clean_re(re) if (re) {\ + pcre_free(re);\ + re = NULL;\ + } + SWITCH_DECLARE(char *) switch_string_replace(const char *string, const char *search, const char *replace); SWITCH_DECLARE(switch_status_t) switch_string_match(const char *string, size_t string_len, const char *search, size_t search_len); +SWITCH_DECLARE(int) switch_perform_regex(char *field, char *expression, pcre **new_re, int *ovector, uint32_t olen); +SWITCH_DECLARE(void) switch_perform_substitution(pcre *re, int match_count, char *data, char *field_data, char *substituted, uint32_t len, int *ovector); #define SWITCH_READ_ACCEPTABLE(status) status == SWITCH_STATUS_SUCCESS || status == SWITCH_STATUS_BREAK SWITCH_DECLARE(size_t) switch_url_encode(char *url, char *buf, size_t len); diff --git a/src/mod/applications/mod_bridgecall/mod_bridgecall.c b/src/mod/applications/mod_bridgecall/mod_bridgecall.c index 52281bd489..87039ff408 100644 --- a/src/mod/applications/mod_bridgecall/mod_bridgecall.c +++ b/src/mod/applications/mod_bridgecall/mod_bridgecall.c @@ -45,6 +45,10 @@ static void audio_bridge_function(switch_core_session_t *session, char *data) uint8_t no_media_bridge = 0; switch_call_cause_t cause = SWITCH_CAUSE_NORMAL_CLEARING; + if (switch_strlen_zero(data)) { + return; + } + caller_channel = switch_core_session_get_channel(session); assert(caller_channel != NULL); diff --git a/src/mod/codecs/mod_gsm/mod_gsm.c b/src/mod/codecs/mod_gsm/mod_gsm.c index e64d4e387c..f0e4063a71 100644 --- a/src/mod/codecs/mod_gsm/mod_gsm.c +++ b/src/mod/codecs/mod_gsm/mod_gsm.c @@ -135,7 +135,7 @@ static switch_status_t switch_gsm_decode(switch_codec_t *codec, switch_codec_t * static const switch_codec_implementation_t gsm_8k_implementation = { /*.codec_type */ SWITCH_CODEC_TYPE_AUDIO, /*.ianacode */ 3, - /*.iananame */ "gsm", + /*.iananame */ "GSM", /*.fmtp */ NULL, /*.samples_per_second */ 8000, /*.bits_per_second */ 13200, diff --git a/src/mod/dialplans/mod_dialplan_xml/mod_dialplan_xml.c b/src/mod/dialplans/mod_dialplan_xml/mod_dialplan_xml.c index 9d6488f4bb..5897b66861 100644 --- a/src/mod/dialplans/mod_dialplan_xml/mod_dialplan_xml.c +++ b/src/mod/dialplans/mod_dialplan_xml/mod_dialplan_xml.c @@ -37,96 +37,8 @@ static const char modname[] = "mod_dialplan_xml"; -#define cleanre(re) if (re) {\ - pcre_free(re);\ - re = NULL;\ - } -static int perform_regex(switch_channel_t *channel, char *field, char *expression, pcre **new_re, int *ovector, uint32_t olen) -{ - const char *error = NULL; - int erroffset = 0; - pcre *re = NULL; - int match_count = 0; - - if (!(field && expression)) { - return 0; - } - - re = pcre_compile(expression, /* the pattern */ - 0, /* default options */ - &error, /* for error message */ - &erroffset, /* for error offset */ - NULL); /* use default character tables */ - if (error) { - switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "COMPILE ERROR: %d [%s]\n", erroffset, error); - cleanre(re); - return 0; - } - - match_count = pcre_exec(re, /* result of pcre_compile() */ - NULL, /* we didn't study the pattern */ - field, /* the subject string */ - (int) strlen(field), /* the length of the subject string */ - 0, /* start at offset 0 in the subject */ - 0, /* default options */ - ovector, /* vector of integers for substring information */ - olen); /* number of elements (NOT size in bytes) */ - - if (match_count <= 0) { - cleanre(re); - match_count = 0; - } - - *new_re = re; - - return match_count; -} - - -static void perform_substitution(pcre *re, int match_count, char *data, char *field_data, char *substituted, uint32_t len, int *ovector) -{ - char index[10] = ""; - char replace[1024] = ""; - uint32_t x, y = 0, z = 0, num = 0; - - for (x = 0; x < (len-1) && x < strlen(data);) { - if (data[x] == '$') { - x++; - - if (!(data[x] > 47 && data[x] < 58)) { - substituted[y++] = data[x-1]; - continue; - } - - while (data[x] > 47 && data[x] < 58) { - index[z++] = data[x]; - x++; - } - index[z++] = '\0'; - z = 0; - num = atoi(index); - - if (pcre_copy_substring(field_data, - ovector, - match_count, - num, - replace, - sizeof(replace)) > 0) { - unsigned int r; - for (r = 0; r < strlen(replace); r++) { - substituted[y++] = replace[r]; - } - } - } else { - substituted[y++] = data[x]; - x++; - } - } - substituted[y++] = '\0'; -} - typedef enum { BREAK_ON_TRUE, BREAK_ON_FALSE, @@ -197,7 +109,7 @@ static int parse_exten(switch_core_session_t *session, switch_xml_t xexten, swit field_data = ""; } switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "test conditions %s(%s) =~ /%s/\n", field, field_data, expression); - if (!(proceed = perform_regex(channel, field_data, expression, &re, ovector, sizeof(ovector) / sizeof(ovector[0])))) { + if (!(proceed = switch_perform_regex(field_data, expression, &re, ovector, sizeof(ovector) / sizeof(ovector[0])))) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Regex mismatch\n"); for (xaction = switch_xml_child(xcond, "anti-action"); xaction; xaction = xaction->next) { @@ -232,7 +144,7 @@ static int parse_exten(switch_core_session_t *session, switch_xml_t xexten, swit char *app_data = NULL; if (field && strchr(expression, '(')) { - perform_substitution(re, proceed, data, field_data, substituted, sizeof(substituted), ovector); + switch_perform_substitution(re, proceed, data, field_data, substituted, sizeof(substituted), ovector); app_data = substituted; } else { app_data = data; @@ -249,7 +161,7 @@ static int parse_exten(switch_core_session_t *session, switch_xml_t xexten, swit switch_caller_extension_add_application(session, *extension, application, app_data); } - cleanre(re); + switch_clean_re(re); if (do_break_i == BREAK_ON_TRUE || do_break_i == BREAK_ALWAYS) { break; diff --git a/src/switch_ivr.c b/src/switch_ivr.c index 646cd96f88..d8ffc7d591 100644 --- a/src/switch_ivr.c +++ b/src/switch_ivr.c @@ -137,7 +137,7 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_park(switch_core_session_t *session) switch_status_t status = SWITCH_STATUS_SUCCESS; switch_channel_t *channel; switch_frame_t *frame; - int stream_id; + int stream_id = 0; switch_event_t *event; channel = switch_core_session_get_channel(session); @@ -152,19 +152,18 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_park(switch_core_session_t *session) switch_channel_set_flag(channel, CF_CONTROLLED); while (switch_channel_ready(channel)) { - for (stream_id = 0; stream_id < switch_core_session_get_stream_count(session); stream_id++) { - if ((status = switch_core_session_read_frame(session, &frame, -1, stream_id)) == SWITCH_STATUS_SUCCESS) { - if (!SWITCH_READ_ACCEPTABLE(status)) { - break; - } - - if (switch_core_session_dequeue_private_event(session, &event) == SWITCH_STATUS_SUCCESS) { - switch_ivr_parse_event(session, event); - switch_event_destroy(&event); - } - - } - } + + if ((status = switch_core_session_read_frame(session, &frame, -1, stream_id)) == SWITCH_STATUS_SUCCESS) { + if (!SWITCH_READ_ACCEPTABLE(status)) { + break; + } + + if (switch_core_session_dequeue_private_event(session, &event) == SWITCH_STATUS_SUCCESS) { + switch_ivr_parse_event(session, event); + switch_event_destroy(&event); + } + } + } switch_channel_clear_flag(channel, CF_CONTROLLED); @@ -966,7 +965,7 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_play_file(switch_core_session_t *sess switch_codec_t codec; switch_memory_pool_t *pool = switch_core_session_get_pool(session); char *codec_name; - int stream_id; + int stream_id = 0; switch_status_t status = SWITCH_STATUS_SUCCESS; switch_file_handle_t lfh; switch_codec_t *read_codec = switch_core_session_get_read_codec(session); @@ -975,11 +974,6 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_play_file(switch_core_session_t *sess uint8_t asis = 0; char *ext; - if (fh->samples > 0) { - sample_start = fh->samples; - fh->samples = 0; - } - if (file) { if ((ext = strrchr(file, '.'))) { ext++; @@ -1000,6 +994,13 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_play_file(switch_core_session_t *sess memset(fh, 0, sizeof(lfh)); } + + if (fh->samples > 0) { + sample_start = fh->samples; + fh->samples = 0; + } + + channel = switch_core_session_get_channel(session); assert(channel != NULL); @@ -1259,21 +1260,23 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_play_file(switch_core_session_t *sess if (!asis) {switch_swap_linear(write_frame.data, (int) write_frame.datalen / 2);} #endif #endif - for (stream_id = 0; stream_id < switch_core_session_get_stream_count(session); stream_id++) { - status = switch_core_session_write_frame(session, &write_frame, -1, stream_id); + stream_id = 0; - if (status == SWITCH_STATUS_MORE_DATA) { - status = SWITCH_STATUS_SUCCESS; - continue; - } else if (status != SWITCH_STATUS_SUCCESS) { - switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); - done = 1; - break; - } - if (done) { - break; - } - } + status = switch_core_session_write_frame(session, &write_frame, -1, stream_id); + + if (status == SWITCH_STATUS_MORE_DATA) { + status = SWITCH_STATUS_SUCCESS; + continue; + } else if (status != SWITCH_STATUS_SUCCESS) { + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); + done = 1; + break; + } + + if (done) { + break; + } + if (timer_name) { if (switch_core_timer_next(&timer) < 0) { @@ -1487,7 +1490,7 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_speak_text_handle(switch_core_session switch_size_t ilen = 0; switch_frame_t write_frame = {0}; int x; - int stream_id; + int stream_id = 0; int done = 0; int lead_in_out = 10; switch_status_t status = SWITCH_STATUS_SUCCESS; @@ -1522,13 +1525,11 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_speak_text_handle(switch_core_session write_frame.codec = codec; for( x = 0; !done && x < lead_in_out; x++) { - for (stream_id = 0; stream_id < switch_core_session_get_stream_count(session); stream_id++) { - if (switch_core_session_write_frame(session, &write_frame, -1, stream_id) != SWITCH_STATUS_SUCCESS) { - switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); - done = 1; - break; - } - } + if (switch_core_session_write_frame(session, &write_frame, -1, stream_id) != SWITCH_STATUS_SUCCESS) { + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); + done = 1; + break; + } } ilen = len; @@ -1606,13 +1607,11 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_speak_text_handle(switch_core_session if (status != SWITCH_STATUS_SUCCESS) { for( x = 0; !done && x < lead_in_out; x++) { - for (stream_id = 0; stream_id < switch_core_session_get_stream_count(session); stream_id++) { - if (switch_core_session_write_frame(session, &write_frame, -1, stream_id) != SWITCH_STATUS_SUCCESS) { - switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); - done = 1; - break; - } - } + if (switch_core_session_write_frame(session, &write_frame, -1, stream_id) != SWITCH_STATUS_SUCCESS) { + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); + done = 1; + break; + } } if (status == SWITCH_STATUS_BREAK) { status = SWITCH_STATUS_SUCCESS; @@ -1627,17 +1626,15 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_speak_text_handle(switch_core_session write_frame.datalen = (uint32_t)ilen; write_frame.samples = (uint32_t)(ilen / 2); - for (stream_id = 0; stream_id < switch_core_session_get_stream_count(session); stream_id++) { - if (switch_core_session_write_frame(session, &write_frame, -1, stream_id) != SWITCH_STATUS_SUCCESS) { - switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); - done = 1; - break; - } + if (switch_core_session_write_frame(session, &write_frame, -1, stream_id) != SWITCH_STATUS_SUCCESS) { + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Write\n"); + done = 1; + break; + } - if (done) { - break; - } - } + if (done) { + break; + } if (timer) { if ((x = switch_core_timer_next(timer)) < 0) { @@ -1686,7 +1683,7 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_speak_text(switch_core_session_t *ses switch_codec_t codec; switch_memory_pool_t *pool = switch_core_session_get_pool(session); char *codec_name; - int stream_id; + int stream_id = 0; switch_status_t status = SWITCH_STATUS_SUCCESS; switch_speech_handle_t sh; switch_speech_flag_t flags = SWITCH_SPEECH_FLAG_NONE; @@ -3130,8 +3127,6 @@ static const switch_state_handler_table_t signal_bridge_state_handlers = { /*.on_hibernate*/ signal_bridge_on_hibernate }; - - SWITCH_DECLARE(switch_status_t) switch_ivr_signal_bridge(switch_core_session_t *session, switch_core_session_t *peer_session) { switch_channel_t *caller_channel, *peer_channel; @@ -3319,9 +3314,15 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_multi_threaded_bridge(switch_core_ses switch_channel_get_name(peer_channel) ); switch_channel_hangup(peer_channel, SWITCH_CAUSE_NO_ANSWER); - } + } done: + + if (switch_channel_get_state(caller_channel) < CS_HANGUP && + switch_true(switch_channel_get_variable(caller_channel, SWITCH_HANGUP_AFTER_BRIDGE_VARIABLE))) { + switch_channel_hangup(caller_channel, SWITCH_CAUSE_NORMAL_CLEARING); + } + return status; } diff --git a/src/switch_utils.c b/src/switch_utils.c index 623942898c..baeed869eb 100644 --- a/src/switch_utils.c +++ b/src/switch_utils.c @@ -35,6 +35,92 @@ #include + +SWITCH_DECLARE(int) switch_perform_regex(char *field, char *expression, pcre **new_re, int *ovector, uint32_t olen) +{ + const char *error = NULL; + int erroffset = 0; + pcre *re = NULL; + int match_count = 0; + + if (!(field && expression)) { + return 0; + } + + re = pcre_compile(expression, /* the pattern */ + 0, /* default options */ + &error, /* for error message */ + &erroffset, /* for error offset */ + NULL); /* use default character tables */ + if (error) { + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "COMPILE ERROR: %d [%s]\n", erroffset, error); + switch_clean_re(re); + return 0; + } + + match_count = pcre_exec(re, /* result of pcre_compile() */ + NULL, /* we didn't study the pattern */ + field, /* the subject string */ + (int) strlen(field), /* the length of the subject string */ + 0, /* start at offset 0 in the subject */ + 0, /* default options */ + ovector, /* vector of integers for substring information */ + olen); /* number of elements (NOT size in bytes) */ + + if (match_count <= 0) { + switch_clean_re(re); + match_count = 0; + } + + *new_re = re; + + return match_count; +} + + +SWITCH_DECLARE(void) switch_perform_substitution(pcre *re, int match_count, char *data, char *field_data, char *substituted, uint32_t len, int *ovector) +{ + char index[10] = ""; + char replace[1024] = ""; + uint32_t x, y = 0, z = 0, num = 0; + + for (x = 0; x < (len-1) && x < strlen(data);) { + if (data[x] == '$') { + x++; + + if (!(data[x] > 47 && data[x] < 58)) { + substituted[y++] = data[x-1]; + continue; + } + + while (data[x] > 47 && data[x] < 58) { + index[z++] = data[x]; + x++; + } + index[z++] = '\0'; + z = 0; + num = atoi(index); + + if (pcre_copy_substring(field_data, + ovector, + match_count, + num, + replace, + sizeof(replace)) > 0) { + unsigned int r; + for (r = 0; r < strlen(replace); r++) { + substituted[y++] = replace[r]; + } + } + } else { + substituted[y++] = data[x]; + x++; + } + } + substituted[y++] = '\0'; +} + + SWITCH_DECLARE(char *) switch_priority_name(switch_priority_t priority) { switch(priority) { /*lol*/