#!/bin/sh ################################################################################# # # Lynis # ------------------ # # Copyright 2007-2013, Michael Boelen # Copyright 2007-2021, CISOfy # # Website : https://cisofy.com # Blog : http://linux-audit.com # GitHub : https://github.com/CISOfy/lynis # # Lynis comes with ABSOLUTELY NO WARRANTY. This is free software, and you are # welcome to redistribute it under the terms of the GNU General Public License. # See LICENSE file for usage of this software. # ################################################################################# # # Squid # ################################################################################# # SQUID_DAEMON_CONFIG_LOCS="${ROOTDIR}etc ${ROOTDIR}etc/squid ${ROOTDIR}etc/squid3 ${ROOTDIR}usr/local/etc/squid ${ROOTDIR}usr/local/squid/etc" SQUID_DAEMON_CONFIG="" SQUID_DAEMON_UNSAFE_PORTS_LIST="22 23 25" SQUID_DAEMON_RUNNING=0 # ################################################################################# # InsertSection "${SECTION_SQUID_SUPPORT}" # ################################################################################# # # Test : SQD-3602 # Description : Check for a running Squid daemon # Notes : Search for squid(3) with a space, to avoid SquidGuard and other # programs. Register --test-no SQD-3602 --weight L --network NO --category security --description "Check for running Squid daemon" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: Searching for a Squid daemon" FOUND=0 # Check running processes FIND=$(${PSBINARY} ax | ${GREPBINARY} -E "(squid|squid3) " | ${GREPBINARY} -v "grep") if [ -n "${FIND}" ]; then SQUID_DAEMON_RUNNING=1 LogText "Result: Squid daemon is running" Display --indent 2 --text "- Checking running Squid daemon" --result "${STATUS_FOUND}" --color GREEN else LogText "Result: No running Squid daemon found" Display --indent 2 --text "- Checking running Squid daemon" --result "${STATUS_NOT_FOUND}" --color WHITE fi fi # ################################################################################# # # Test : SQD-3604 # Description : Determine Squid daemon configuration file location if [ ${SQUID_DAEMON_RUNNING} -eq 1 ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3604 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid daemon file location" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: searching for squid.conf or squid3.conf file" for I in ${SQUID_DAEMON_CONFIG_LOCS}; do # Checking squid.conf if [ -f "${I}/squid.conf" ]; then LogText "Result: ${I}/squid.conf exists" SQUID_DAEMON_CONFIG="${I}/squid.conf" fi # Checking squid3.conf if [ -f "${I}/squid3.conf" ]; then LogText "Result: ${I}/squid3.conf exists" SQUID_DAEMON_CONFIG="${I}/squid3.conf" fi done if [ -z "${SQUID_DAEMON_CONFIG}" ]; then LogText "Result: No Squid configuration file found" Display --indent 4 --text "- Searching Squid configuration file" --result "${STATUS_NOT_FOUND}" --color YELLOW else LogText "Result: using last found configuration file: ${SQUID_DAEMON_CONFIG}" Display --indent 4 --text "- Searching Squid configuration" --result "${STATUS_FOUND}" --color GREEN fi fi # ################################################################################# # # Test : SQD-3606 # Description : Check Squid version if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3606 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid version" if [ ${SKIPTEST} -eq 0 ]; then if [ -n "${SQUIDBINARY}" ]; then LogText "Result: Squid binary found (${SQUIDBINARY})" # Skip check if a setuid/setgid bit is found FIND=$(${FINDBINARY} ${SQUIDBINARY} \( -perm 4000 -o -perm 2000 \) -print) if [ -z "${FIND}" ]; then FIND2=$(${SQUIDBINARY} -v | ${AWKBINARY} '{ if ($3=="Version") { print $4 } }') Display --indent 4 --text "- Checking Squid version" --result "${STATUS_FOUND}" --color GREEN SQUID_VERSION="${FIND2}" else LogText "Result: test skipped for security reasons, setuid/setgid bit set" Display --indent 4 --text "- Checking Squid version" --result "${STATUS_SKIPPED}" --color RED fi else LogText "Result: no Squid binary found" fi fi # ################################################################################# # # Test : SQD-3610 # Description : Check Squid configuration options if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3610 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Gather Squid settings" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: Checking all specific defined options in ${SQUID_DAEMON_CONFIG}" FIND=$(${GREPBINARY} -v "^#" ${SQUID_DAEMON_CONFIG} | ${GREPBINARY} -v "^$" | ${AWKBINARY} '{gsub("\t"," ");print}' | ${SEDBINARY} 's/ /!space!/g') for I in ${FIND}; do I=$(echo ${I} | ${SEDBINARY} 's/!space!/ /g') LogText "Found Squid option: ${I}" Report "squid_option=${I}" done Display --indent 4 --text "- Checking defined Squid options" --result "${STATUS_DONE}" --color GREEN fi # ################################################################################# # # Test : SQD-3613 # Description : Check Squid configuration file permissions if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3613 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid file permissions" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: Checking file permissions of ${SQUID_DAEMON_CONFIG}" FIND=$(find -L ${SQUID_DAEMON_CONFIG} -type f -a \( -perm -004 -o -perm -002 -o -perm -001 \)) if [ -n "${FIND}" ]; then LogText "Result: file ${SQUID_DAEMON_CONFIG} is world readable, writable or executable and could leak information or passwords" Display --indent 4 --text "- Checking Squid configuration file permissions" --result "${STATUS_WARNING}" --color RED ReportSuggestion "${TEST_NO}" "Check file permissions of ${SQUID_DAEMON_CONFIG} to limit access" ReportWarning "${TEST_NO}" "File permissions of ${SQUID_DAEMON_CONFIG} are not restrictive" AddHP 0 2 else LogText "Result: file ${SQUID_DAEMON_CONFIG} has proper file permissions" Display --indent 4 --text "- Checking Squid configuration file permissions" --result "${STATUS_OK}" --color GREEN AddHP 2 2 fi fi # ################################################################################# # if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then Display --indent 4 --text "- Checking Squid access control" fi # ################################################################################# # # Test : SQD-3614 # Description : Check Squid authentication if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3614 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid authentication methods" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: check auth_param option for authentication methods" FIND=$(${GREPBINARY} "^auth_param" ${SQUID_DAEMON_CONFIG} | ${AWKBINARY} '{ print $2 }') if [ -z "${FIND}" ]; then LogText "No auth_param option found, proxy access anonymous or based on other methods (like ACLs)" Display --indent 6 --text "- Checking Squid authentication methods" --result "${STATUS_NONE}" --color YELLOW else Display --indent 6 --text "- Checking Squid authentication methods" --result "${STATUS_FOUND}" --color GREEN for I in ${FIND}; do LogText "Result: found authentication method ${I}" Report "squid_auth_method=${I}" done fi fi # ################################################################################# # # Test : SQD-3616 # Description : Check external Squid authentication if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3616 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check external Squid authentication" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: check external_acl_type option for external authentication helpers" FIND=$(${GREPBINARY} "^external_acl_type" ${SQUID_DAEMON_CONFIG}) if [ -z "${FIND}" ]; then LogText "No external_acl_type found" Display --indent 6 --text "- Checking Squid external authentication methods" --result "${STATUS_NONE}" --color YELLOW else Display --indent 6 --text "- Checking Squid external authentication methods" --result "${STATUS_FOUND}" --color GREEN for I in ${FIND}; do LogText "Result: found external authentication method helper" LogText "Output: ${FIND}" #Report "squid_external_acl_type=TRUE" done fi fi # ################################################################################# # # Test : SQD-3620 # Description : Check ACLs if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a ! "${SQUID_DAEMON_CONFIG}" = "" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3620 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid access control lists" if [ ${SKIPTEST} -eq 0 ]; then COUNT=0 LogText "Test: checking ACLs" FIND=$(${GREPBINARY} "^acl " ${SQUID_DAEMON_CONFIG} | ${SEDBINARY} 's/ /!space!/g') if [ "${FIND}" = "" ]; then LogText "Result: No ACLs found" Display --indent 6 --text "- Checking Access Control Lists" --result "${STATUS_NONE}" --color RED else for ITEM in ${FIND}; do COUNT=$((COUNT + 1)) ITEM=$(echo ${ITEM} | ${SEDBINARY} 's/!space!/ /g') LogText "Found ACL: ${ITEM}" #Report "squid_acl=${ITEM}" # TODO done LogText "Result: Found ${COUNT} ACLs" Display --indent 6 --text "- Checking Access Control Lists" --result "${COUNT} ACLs FOUND" --color GREEN fi fi # ################################################################################# # # Test : SQD-3624 # Description : Check insecure ports in Safe_ports list if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a ! "${SQUID_DAEMON_CONFIG}" = "" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3624 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid safe ports" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: checking ACL Safe_ports http_access option" FIND=$(${GREPBINARY} "^http_access" ${SQUID_DAEMON_CONFIG} | ${GREPBINARY} "Safe_ports") if IsEmpty "${FIND}"; then LogText "Result: no Safe_ports found" Display --indent 6 --text "- Checking ACL 'Safe_ports' http_access option" --result "${STATUS_NOT_FOUND}" --color YELLOW ReportSuggestion "${TEST_NO}" "Check if Squid has been configured to restrict access to all safe ports" else LogText "Result: checking ACL safe ports" FIND2=$(${GREPBINARY} "^acl Safe_ports port" ${SQUID_DAEMON_CONFIG} | ${AWKBINARY} '{ print $4 }') if IsEmpty "${FIND2}"; then Display --indent 6 --text "- Checking ACL 'Safe_ports' ports" --result "NONE FOUND" --color YELLOW ReportSuggestion "${TEST_NO}" "Check if Squid has been configured for which ports it can allow outgoing traffic (Safe_ports)" AddHP 0 1 else LogText "Result: Safe_ports found" for ITEM in ${FIND}; do LogText "Found safe port: ${ITEM}" done Display --indent 6 --text "- Checking ACL 'Safe_ports' ports" --result "${STATUS_FOUND}" --color GREEN AddHP 1 1 fi for ITEM in ${SQUID_DAEMON_UNSAFE_PORTS_LIST}; do LogText "Test: Checking port ${ITEM} in Safe_ports list" FIND2=$(${GREPBINARY} -w "^acl Safe_ports port ${ITEM}" ${SQUID_DAEMON_CONFIG}) if IsEmpty "${FIND2}"; then Display --indent 6 --text "- Checking ACL 'Safe_ports' (port ${ITEM})" --result "${STATUS_NOT_FOUND}" --color GREEN AddHP 1 1 else Display --indent 6 --text "- Checking ACL 'Safe_ports' (port ${ITEM})" --result "${STATUS_FOUND}" --color RED ReportWarning "${TEST_NO}" "Squid configuration possibly allows relaying traffic via configured Safe_port ${ITEM}" AddHP 0 1 fi done fi fi # ################################################################################# # if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then Display --indent 4 --text "- Checking Squid Denial of Service tuning options" fi # ################################################################################# # # Test : SQD-3630 [T] # Description : Check reply_body_max_size value if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3630 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid reply_body_max_size option" if [ ${SKIPTEST} -eq 0 ]; then LogText "Test: checking option reply_body_max_size" FIND=$(${GREPBINARY} "^reply_body_max_size " ${SQUID_DAEMON_CONFIG} | ${SEDBINARY} 's/ /!space!/g') if IsEmpty "${FIND}"; then LogText "Result: option reply_body_max_size not configured" Display --indent 6 --text "- Checking option: reply_body_max_size" --result "${STATUS_NONE}" --color RED AddHP 1 2 ReportSuggestion "${TEST_NO}" "Configure Squid option reply_body_max_size to limit the upper size of requests." else LogText "Result: option reply_body_max_size configured" LogText "Output: ${FIND}" Display --indent 6 --text "- Checking option: reply_body_max_size" --result "${STATUS_FOUND}" --color GREEN AddHP 2 2 fi fi # ################################################################################# # if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then Display --indent 4 --text "- Checking Squid general options" fi # ################################################################################# # # Test : SQD-3680 # Description : Check httpd_suppress_version_string if [ ${SQUID_DAEMON_RUNNING} -eq 1 -a -n "${SQUID_DAEMON_CONFIG}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi Register --test-no SQD-3680 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check Squid version suppression" if [ ${SKIPTEST} -eq 0 ]; then FIND=$(${GREPBINARY} "^httpd_suppress_version_string " ${SQUID_DAEMON_CONFIG} | ${GREPBINARY} " on") if [ -z "${FIND}" ]; then LogText "Result: option httpd_suppress_version_string not configured" Display --indent 6 --text "- Checking option: httpd_suppress_version_string" --result "${STATUS_NOT_FOUND}" --color YELLOW AddHP 1 2 ReportSuggestion "${TEST_NO}" "Configure Squid option httpd_suppress_version_string (on) to suppress the version." else LogText "Result: option httpd_suppress_version_string configured" LogText "Output: ${FIND}" Display --indent 6 --text "- Checking option: httpd_suppress_version_string" --result "${STATUS_FOUND}" --color GREEN AddHP 2 2 fi fi # ################################################################################# # WaitForKeyPress # #================================================================================ # Lynis - Copyright 2007-2021 Michael Boelen, CISOfy - https://cisofy.com