#!/usr/bin/env bash

# Copyright 2018 Toni de la Fuente

# Prowler is a tool that provides automate auditing and hardening guidance of an
# AWS account. It is based on AWS-CLI commands. It follows some guidelines
# present in the CIS Amazon Web Services Foundations Benchmark at:
# https://d0.awsstatic.com/whitepapers/compliance/AWS_CIS_Foundations_Benchmark.pdf

# Contact the author at https://blyx.com/contact
# and open issues or ask questions at https://github.com/prowler-cloud/prowler

# Code is licensed as Apache License 2.0 as specified in
# each file. You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0

# Function to execute the check
execute_check() {
  if [[ -n "${ACCOUNT_TO_ASSUME}" || -n "${ROLE_TO_ASSUME}" || "${PROFILE}" == "INSTANCE-PROFILE" ]]; then
    # echo ******* I am here again to check on my role *******
    # Following logic looks for time remaining in the session and review it
    # if it is less than 600 seconds, 10 minutes.
    CURRENT_TIMESTAMP=$(date -u "+%s")
    SESSION_TIME_REMAINING=$(expr "${AWS_SESSION_EXPIRATION}" - "${CURRENT_TIMESTAMP}")
    MINIMUM_REMAINING_TIME_ALLOWED=600
    if (( "${MINIMUM_REMAINING_TIME_ALLOWED}" > "${SESSION_TIME_REMAINING}" )); then
      # echo LESS THAN 10 MIN LEFT: RE-ASSUMING...
      unset AWS_ACCESS_KEY_ID
      unset AWS_SECRET_ACCESS_KEY
      unset AWS_SESSION_TOKEN
      if [[ "${PROFILE}" == "INSTANCE-PROFILE" ]]; then
        if [[ -n "${AWS_CONTAINER_CREDENTIALS_RELATIVE_URI}" ]]; then
          INSTANCE_METADATA_URI="169.254.170.2${AWS_CONTAINER_CREDENTIALS_RELATIVE_URI}"
        else
          INSTANCE_METADATA_URI="http://169.254.169.254/latest/meta-data/iam/security-credentials/${INSTANCE_PROFILE}"
        fi
        set_metadata_credentials "${INSTANCE_METADATA_URI}"
      else
        assume_role
      fi
    fi
  fi

  CHECK_ID="$1"

  # See if this is an alternate name for a check
  # for example, we might have been passed 1.01 which is another name for 1.1
  local alternate_name_var=CHECK_ALTERNATE_$1
  local alternate_name=${!alternate_name_var}
  # See if this check defines an ASFF Type, if so, use this, falling back to a sane default
  # For a list of Types Taxonomy, see: https://docs.aws.amazon.com/securityhub/latest/userguide/securityhub-findings-format-type-taxonomy.html
  local asff_type_var=CHECK_ASFF_TYPE_$1
  CHECK_ASFF_TYPE="${!asff_type_var:-Software and Configuration Checks}"

  local asff_compliance_type_var=CHECK_ASFF_COMPLIANCE_TYPE_$1
  CHECK_ASFF_COMPLIANCE_TYPE="${!asff_compliance_type_var:-Software and Configuration Checks}"

  # See if this check defines an ASFF Resource Type, if so, use this, falling back to a sane default
  # For a list of Resource Types, see: https://docs.aws.amazon.com/securityhub/latest/userguide/securityhub-findings-format.html#asff-resources
  local asff_resource_type_var=CHECK_ASFF_RESOURCE_TYPE_$1
  CHECK_ASFF_RESOURCE_TYPE="${!asff_resource_type_var:-AwsAccount}"

  local severity_var=CHECK_SEVERITY_$1
  CHECK_SEVERITY="${!severity_var}"

  local servicename_var=CHECK_SERVICENAME_$1
  CHECK_SERVICENAME="${!servicename_var}"

  local risk_var=CHECK_RISK_$1
  CHECK_RISK="${!risk_var}"

  local remediation_var=CHECK_REMEDIATION_$1
  CHECK_REMEDIATION="${!remediation_var}"

  local doc_var=CHECK_DOC_$1
  CHECK_DOC="${!doc_var}"

  local caf_epic_var=CHECK_CAF_EPIC_$1
  CHECK_CAF_EPIC="${!caf_epic_var}"

  SECURITYHUB_NEW_FINDINGS_IDS=()

  # Generate the credential report, only if it is group1 related which checks we
  # run so that the checks can safely assume it's available
  # set the custom ignores list for this check
  ignores="$(awk "/${1}/{print}" <(echo "${ALLOWLIST}"))"

  if [ ${alternate_name} ];then
    if [[ ${alternate_name} == check1* || ${alternate_name} == extra71 || ${alternate_name} == extra774 || ${alternate_name} == extra7123 ]];then
      if [ ! -s $TEMP_REPORT_FILE ];then
        genCredReport
        saveReport
      fi
    fi
    show_check_title ${alternate_name}
    if [[ " ${MODE} " =~ "junit-xml" ]]; then
      prepare_junit_check_output "$1"
    fi
    # Execute the check
    IGNORES="${ignores}" CHECK_NAME="$1" ${alternate_name}
    if [[ " ${MODE} " =~ "junit-xml" ]]; then
      finalise_junit_check_output "$1"
    fi

    if [[ "$SEND_TO_SECURITY_HUB" -eq 1 ]]; then
      resolveSecurityHubPreviousFails "$1"
    fi
  else
    # Check to see if this is a real check
    local check_id_var=CHECK_ID_$1
    local check_id=${!check_id_var}
    if [ ${check_id} ]; then
      if [[ ${check_id} == 1* || ${check_id} == 7.1 || ${check_id} == 7.74 || ${check_id} == 7.123 ]];then
        if [ ! -s $TEMP_REPORT_FILE ];then
          genCredReport
          saveReport
        fi
      fi
      show_check_title "$1"
      if [[ " ${MODE} " =~ "junit-xml" ]]; then
        prepare_junit_check_output "$1"
      fi
      # Execute the check
      IGNORES="${ignores}" CHECK_NAME="$1" $1

      if [[ " ${MODE} " =~ "junit-xml" ]]; then
        finalise_junit_check_output "$1"
      fi

      if [[ "$SEND_TO_SECURITY_HUB" -eq 1 ]]; then
        resolveSecurityHubPreviousFails "$1"
      fi

    else
      textFail "Check ${CHECK_ID} does not exist. Use a valid check name (i.e. check41 or extra71)";
      exit $EXITCODE
    fi
  fi
}