#!/bin/sh
#################################################################################
#
# Lynis
# ------------------
#
# Copyright 2007-2015, Michael Boelen, CISOfy (michael.boelen@cisofy.com)
# Web site: https://cisofy.com
#
# 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.
#
#################################################################################
#
# Networking
#
#################################################################################
#
FOUNDPROMISC=0 # Promiscuous interfaces
LOCAL_DNSRESOLVER_FOUND=0 # Local DNS resolver
NUMBERACTIVENS=0 # Number of active nameservers
DHCP_CLIENT_RUNNING=0 # DHCP client availability
#
#################################################################################
#
InsertSection "Networking"
#
#################################################################################
#
# Test : NETW-2704
# Description : Basic nameserver configuration tests (connectivity)
Register --test-no NETW-2704 --weight L --network YES --description "Basic nameserver configuration tests"
if [ ${SKIPTEST} -eq 0 ]; then
Display --indent 2 --text "- Checking configured nameservers"
logtext "Test: Checking /etc/resolv.conf file"
if [ -f /etc/resolv.conf ]; then
logtext "Result: Found /etc/resolv.conf file"
FIND=`grep '^nameserver' /etc/resolv.conf | tr -d '\t' | sed 's/nameserver*//g' | uniq`
if [ ! "${FIND}" = "" ]; then
Display --indent 4 --text "- Testing nameservers"
logtext "Test: Querying nameservers"
for I in ${FIND}; do
logtext "Found nameserver: ${I}"
report "nameserver[]=${I}"
# Check if a local resolver is available (like DNSMasq)
if [ "${I}" = "::1" -o "${I}" = "127.0.0.1" -o "${I}" = "0.0.0.0" ]; then
LOCAL_DNSRESOLVER_FOUND=1
fi
if [ ! "${DIGBINARY}" = "" ]; then
# See if we can query something at the nameserver
# 0=good, other=bad
DNSRESPONSE=`${DIGBINARY} +noall +time=3 +retry=0 @${I} ${I} > /dev/null ; echo $?`
if [ "${DNSRESPONSE}" = "0" ]; then
Display --indent 8 --text "Nameserver: ${I}" --result OK --color GREEN
logtext "Nameserver ${I} seems to respond to queries from this host."
# Count responsive nameservers
NUMBERACTIVENS=`expr ${NUMBERACTIVENS} + 1`
else
Display --indent 8 --text "Nameserver: ${I}" --result "NO RESPONSE" --color RED
logtext "Result: nameserver ${I} does NOT respond"
logtext "Exit-code from dig: ${DNSRESPONSE}"
ReportSuggestion ${TEST_NO} "Check connection to this nameserver and make sure no outbound DNS queries are blocked (port 53 UDP and TCP)."
ReportWarning ${TEST_NO} "L" "Nameserver ${I} does not respond"
fi
else
logtext "Result: Nameserver test for ${I} skipped, 'dig' not installed"
Display --indent 6 --text "Nameserver: ${I}" --result SKIPPED --color YELLOW
fi
done
fi
fi
fi
#
#################################################################################
#
# Test : NETW-2705
# Description : Basic nameserver configuration tests (connectivity)
if [ ${LOCAL_DNSRESOLVER_FOUND} -eq 0 ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no NETW-2705 --preqs-met ${PREQS_MET} --weight L --network YES --description "Check availability two nameservers"
if [ ${SKIPTEST} -eq 0 ]; then
if [ ! "${DIGBINARY}" = "" ]; then
if [ ${NUMBERACTIVENS} -lt 2 ]; then
Display --indent 4 --text "- Minimal of 2 responsive nameservers" --result WARNING --color RED
logtext "Result: less than 2 responsive nameservers found"
ReportWarning ${TEST_NO} "L" "Couldn't find 2 responsive nameservers"
logtext "Note: Non responsive nameservers can give problems for your system(s). Like the lack of recursive lookups, bad connectivity to update servers etc."
ReportSuggestion ${TEST_NO} "Check your resolv.conf file and fill in a backup nameserver if possible"
AddHP 1 2
else
Display --indent 4 --text "- Minimal of 2 responsive nameservers" --result OK --color GREEN
logtext "Result: found at least 2 responsive nameservers"
AddHP 3 3
fi
else
Display --indent 4 --text "- Minimal of 2 responsive nameservers" --result SKIPPED --color YELLOW
logtext "Result: dig not installed, test can't be fully performed"
fi
else
logtext "Result: Test most likely skipped due having local resolver in /etc/resolv.conf"
fi
#
#################################################################################
#
# Test : NETW-3001
# Description : Find default gateway (route)
# More info : BSD: ^default Linux: 0.0.0.0
if [ ! "${NETSTATBINARY}" = "" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no NETW-3001 --preqs-met ${PREQS_MET} --weight L --network NO --description "Find default gateway (route)"
if [ $SKIPTEST -eq 0 ]; then
logtext "Test: Searching default gateway(s)"
FIND=`${NETSTATBINARY} -rn | egrep "^0.0.0.0|default" | tr -s ' ' | cut -d ' ' -f2`
if [ ! "${FIND}" = "" ]; then
for I in ${FIND}; do
logtext "Result: Found default gateway ${I}"
report "default_gateway[]=${I}"
done
Display --indent 2 --text "- Checking default gateway" --result DONE --color GREEN
else
logtext "Result: No default gateway found"
Display --indent 2 --text "- Checking default gateway" --result "NONE FOUND" --color WHITE
fi
fi
#
#################################################################################
#
# Test : NETW-3004
# Description : Find available network interfaces on FreeBSD and others
if [ "${OS}" = "DragonFly" -o "${OS}" = "FreeBSD" -o "${OS}" = "NetBSD" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no NETW-3004 --preqs-met ${PREQS_MET} --weight L --network NO --description "Search available network interfaces on FreeBSD and others"
if [ ${SKIPTEST} -eq 0 ]; then
FIND=`${IFCONFIGBINARY} -l`
N=0
for I in ${FIND}; do
logtext "Found network interface: ${I}"
N=`expr ${N} + 1`
report "network_interface[]=${I}"
done
fi
#
#################################################################################
#
# Test : NETW-3006
# Description : Get network MAC addresses
Register --test-no NETW-3006 --weight L --network NO --description "Get network MAC addresses"
if [ ${SKIPTEST} -eq 0 ]; then
FIND=""
case ${OS} in
AIX)
FIND=`lscfg -vl ent* | fgrep "Network Address" | cut -d"." -f14 | awk '{ ctr=1; i=1; while (ctr <= 6) { d[ctr++]=substr($0,i,2);i=i+2 } printf("%s:%s:%s:%s:%s:%s\n",d[1],d[2],d[3],d[4],d[5],d[6]) }'`
;;
DragonFly|FreeBSD)
FIND=`${IFCONFIGBINARY} -a | ${AWKBINARY} '{ if ($1=="ether") print $2 }' | sort | uniq`
;;
Linux)
if [ ! "${IFCONFIGBINARY}" = "" ]; then
FIND=`${IFCONFIGBINARY} -a | ${GREPBINARY} "HWaddr" | awk '{ if ($4=="HWaddr") print $5 }' | sort | uniq`
else
if [ ! "${IPBINARY}" = "" ]; then
logtext "Test: Using ip binary to gather hardware addresses"
FIND=`${IPBINARY} link | ${GREPBINARY} "link/ether" | ${AWKBINARY} '{ print $2 }'`
else
ReportException "${TEST_NO}:2" "Missing ifconfig or ip command to collect hardware address (MAC)"
fi
fi
;;
MacOS)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="lladdr" || $1=="ether") print $2 }' | sort | uniq`
;;
NetBSD)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="address:") print $2 }' | sort | uniq`
;;
OpenBSD)
FIND=`${IFCONFIGBINARY} -A | awk '{ if ($1=="lladdr") print $2 }' | sort | uniq`
;;
Solaris)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="ether") print $2 }' | sort | uniq`
;;
*)
# Having a system currently unsupported? Share your details to determine MAC information
ReportException "${TEST_NO}:1" "No support for this OS (${OS}) to find MAC information"
;;
esac
N=0
for I in ${FIND}; do
logtext "Found MAC address: ${I}"
N=`expr ${N} + 1`
report "network_mac_address[]=${I}"
done
fi
#
#################################################################################
#
# Test : NETW-3008
# Description : Get network IPv4/6 addresses
Register --test-no NETW-3008 --weight L --network NO --description "Get network IP addresses"
if [ ${SKIPTEST} -eq 0 ]; then
FIND=""; FIND2=""
case ${OS} in
AIX)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet") print $2 }'`
FIND2=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet6") print $2 }'`
;;
DragonFly|FreeBSD|NetBSD)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet") print $2 }'`
FIND2=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet6") print $2 }'`
;;
Linux)
if [ ! "${IFCONFIGBINARY}" = "" ]; then
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet") print $2 }' | cut -d ':' -f2`
# Version which works for multiple types of ifconfig (e.g. Slackware)
FIND2=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet6" && $2=="addr:") { print $3 } else { if ($1=="inet6" && $3=="prefixlen") { print $2 } } }'`
else
if [ ! "${IPBINARY}" = "" ]; then
logtext "Test: Using ip binary to gather IP addresses"
FIND=`${IPBINARY} addr | ${AWKBINARY} '{ if ($1=="inet") { print $2 }}' | sed 's/\/.*//'`
FIND2=`${IPBINARY} addr | ${AWKBINARY} '{ if ($1=="inet6") { print $2 }}' | sed 's/\/.*//'`
else
ReportException "${TEST_NO}:2" "Missing ifconfig or ip command to collect hardware address (MAC)"
fi
fi
;;
MacOS)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet") print $2 }'`
FIND2=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet6") print $2 }'`
;;
OpenBSD)
FIND=`${IFCONFIGBINARY} -A | awk '{ if ($1=="inet") print $2 }'`
FIND2=`${IFCONFIGBINARY} -A | awk '{ if ($1=="inet6") print $2 }'`
;;
Solaris)
FIND=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet") print $2 }'`
FIND2=`${IFCONFIGBINARY} -a | awk '{ if ($1=="inet6") print $2 }'`
;;
*)
logtext "Result: no support yet for this OS (${OS}) to find IP address information. You can help improving this test by submitting your details."
ReportException "${TEST_NO}:1" "IP address information test not implemented for this operating system"
;;
esac
N=0
# IPv4
for I in ${FIND}; do
logtext "Found IPv4 address: ${I}"
N=`expr ${N} + 1`
report "network_ipv4_address[]=${I}"
done
# IPv6
for I in ${FIND2}; do
logtext "Found IPv6 address: ${I}"
N=`expr ${N} + 1`
report "network_ipv6_address[]=${I}"
done
fi
#
#################################################################################
#
# Test : NETW-3012
# Description : Check listening ports
Register --test-no NETW-3012 --weight L --network NO --description "Check listening ports"
if [ ${SKIPTEST} -eq 0 ]; then
FIND=""; FIND2=""
N=0
case ${OS} in
DragonFly|FreeBSD)
if [ ! "${SOCKSTATBINARY}" = "" ]; then
FIND=`${SOCKSTATBINARY} | awk '{ if ($7 ~ /\*:\*/) print $5"|"$6"|"$2"|" }' | sort | uniq`
# To strip off IP's: sed 's/|.*:/|/'
else
FIND=""
fi
FIND2=""
;;
Linux)
if [ ! "${NETSTATBINARY}" = "" ]; then
# UDP
FIND=`${NETSTATBINARY} -nlp 2> /dev/null | grep "^udp" | awk '{ print $4"|"$1"|"$6"|" }' | sed 's:|[0-9]*/:|:'`
# TCP
FIND2=`${NETSTATBINARY} -nlp 2> /dev/null | grep "^tcp" | awk '{ if($6=="LISTEN") { print $4"|"$1"|"$7"|" }}' | sed 's:|[0-9]*/:|:'`
else
if [ ! "${SSBINARY}" = "" ]; then
# UDP
FIND=`${SSBINARY} -u -a -n | awk '{ print $4 }' | grep -v Local`
# TCP
FIND2=`${SSBINARY} -t -a -n | awk '{ print $4 }' | grep -v Local`
else
ReportException "${TEST_NO}:1" "netstat and ss binary missing to gather listening ports"
fi
fi
;;
MacOS)
if [ ! "${LSOFBINARY}" = "" ]; then
# UDP and TCP combined
FIND=`${LSOFBINARY} -i -P | awk '{ print $9"|"$8"|"$1"|" }' | sed 's/\(.*\)\-\>.*\(\|.*\)/\1\2/' | sed 's/\*/'$IP'/' | sort -u | grep -v "NAME"`
else
FIND=""
fi
# Not needed as we have a combined test
FIND2=""
;;
NetBSD)
if [ ! "${SOCKSTATBINARY}" = "" ]; then
FIND=`${SOCKSTATBINARY} | awk '{ if ($7 ~ /\*.\*/) print $5"|"$6"|"$2"|" }' | sort | uniq`
else
FIND=""
fi
FIND2=""
;;
OpenBSD)
if [ ! "${NETSTATBINARY}" = "" ]; then
# UDP
FIND=`${NETSTATBINARY} -an 2> /dev/null | grep "^udp" | awk '{ print $4"|"$1"||" }'`
# TCP
FIND2=`${NETSTATBINARY} -an 2> /dev/null | grep "^tcp" | awk '{ if($6=="LISTEN") { print $4"|"$1"||" }}'`
else
ReportException "${TEST_NO}:3" "netstat missing to gather listening ports"
fi
;;
*)
# Got this exception? Provide your details and output of netstat or any other tool to determine this information.
ReportException "${TEST_NO}:2" "Unclear what method to use, to determine listening port information"
;;
esac
# Retrieve information from sockstat, when available
logtext "Test: Retrieving sockstat information to find listening ports"
if [ ! "${FIND}" = "" ]; then
for I in ${FIND}; do
N=`expr ${N} + 1`
logtext "Found listening info: ${I}"
report "network_listen_port[]=${I}"
done
fi
if [ ! "${FIND2}" = "" ]; then
for I in ${FIND2}; do
N=`expr ${N} + 1`
logtext "Found listening info: ${I}"
report "network_listen_port[]=${I}"
done
fi
if [ "${FIND}" = "" -a "${FIND2}" = "" ]; then
Display --indent 2 --text "- Getting listening ports (TCP/UDP)" --result SKIPPED --color YELLOW
else
Display --indent 2 --text "- Getting listening ports (TCP/UDP)" --result DONE --color GREEN
Display --indent 6 --text "* Found ${N} ports"
fi
fi
#
#################################################################################
#
# Test : NETW-3014
# Description : Checking promiscuous interfaces (BSD)
# Note : FreeBSD and others
if [ "${OS}" = "DragonFly" -o "${OS}" = "FreeBSD" -o "${OS}" = "NetBSD" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no NETW-3014 --preqs-met ${PREQS_MET} --weight L --network NO --description "Checking promiscuous interfaces (BSD)"
if [ ${SKIPTEST} -eq 0 ]; then
logtext "Test: Checking promiscuous interfaces (FreeBSD)"
FIND=`${IFCONFIGBINARY} | grep PROMISC | cut -d ':' -f1`
if [ ! "${FIND}" = "" ]; then
logtext "Result: Promiscuous interfaces: ${FIND}"
for I in ${FIND}; do
ISWHITELISTED=`grep "^if_promisc:${I}:" ${PROFILE}`
if [ "${ISWHITELISTED}" = "" ]; then
FOUNDPROMISC=1
ReportWarning ${TEST_NO} "H" "Found promiscuous interface (${I})"
logtext "Note: some tools put an interface into promiscuous mode, to capture/log network traffic"
else
logtext "Result: Found promiscuous interface ${I} (*whitelisted via profile*)"
fi
done
fi
# Show result
if [ ${FOUNDPROMISC} -eq 0 ]; then
Display --indent 2 --text "- Checking promiscuous interfaces" --result OK --color GREEN
logtext "Result: No promiscuous interfaces found"
else
Display --indent 2 --text "- Checking promiscuous interfaces" --result WARNING --color RED
fi
fi
#
#################################################################################
#
# Test : NETW-3015
# Description : Checking promiscuous interfaces (Linux)
# Note : Need ifconfig binary at this moment (does not work on Arch Linux)
if [ ! "${IFCONFIGBINARY}" = "" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no NETW-3015 --os Linux --preqs-met ${PREQS_MET} --weight L --network NO --description "Checking promiscuous interfaces (Linux)"
if [ ${SKIPTEST} -eq 0 ]; then
logtext "Test: Checking promiscuous interfaces (Linux)"
NETWORK=`${IFCONFIGBINARY} | grep Link | tr -s ' ' | cut -d ' ' -f1`
if [ ! "${NETWORK}" = "" ]; then
for I in ${NETWORK}; do
FIND=`${IFCONFIGBINARY} ${I} | grep PROMISC`
if [ ! "${FIND}" = "" ]; then
logtext "Result: Promiscuous interface: ${I}"
ISWHITELISTED=`grep "^if_promisc:${I}:" ${PROFILE}`
if [ "${ISWHITELISTED}" = "" ]; then
FOUNDPROMISC=1
ReportWarning ${TEST_NO} "H" "Found promiscuous interface (${I})"
logtext "Note: some tools put an interface into promiscuous mode, to capture/log network traffic"
else
logtext "Result: Found promiscuous interface ${I} (*whitelisted via profile*)"
fi
fi
done
fi
# Show result
if [ ${FOUNDPROMISC} -eq 0 ]; then
Display --indent 2 --text "- Checking promiscuous interfaces" --result OK --color GREEN
logtext "Result: No promiscuous interfaces found"
else
Display --indent 2 --text "- Checking promiscuous interfaces" --result WARNING --color RED
fi
fi
#
#################################################################################
#
# Test : NETW-3020
# Description : Checking multipath configuration (Solaris)
#
#################################################################################
#
# Test : NETW-3024
# Description : Netstat/socktstat compare (FreeBSD)
# echo -n " - Comparing output sockstat and netstat"
# logtext "Comparing output of sockstat and netstat"
# NETSTATOUTPUT=`netstat -an | grep -v 'TIME_WAIT' | grep -v 'ESTABLISHED' | grep -v 'SYN_SENT' | grep -v 'CLOSE_WAIT' | grep -v 'LAST_ACK' | grep -v 'SYN_RECV' | grep -v 'CLOSING' | cut -c 1-44 | grep '*.' | cut -c 24-32 | tr -d ' ' | tr -d '\t' | grep -v '*' | sort | uniq`
#
# if [ "${SOCKSTATOUTPUT}" = "${NETSTATOUTPUT}" ]; then
# ShowResult OK
# else
# echo "[ ${BAD}Warning!${NORMAL} ]"
# logtext "WARNING!"
# logtext "Sockstat tested output: ${SOCKSTAT}"
# logtext "Netstat tested output: ${NETSTAT}"
# fi
#
#################################################################################
#
# Test : NETW-3028
# Description : Checking for many waiting connections
# Type : Performance
# Notes : It is common to see a healthy web server seeing to have several thousands of TCP connections in WAIT state
if [ ! "${NETSTATBINARY}" = "" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no NETW-3028 --preqs-met ${PREQS_MET} --weight L --network NO --description "Checking connections in WAIT state"
if [ ${SKIPTEST} -eq 0 ]; then
logtext "Test: Using netstat for check for connections in WAIT state"
FIND=`${NETSTATBINARY} -an | grep WAIT | wc -l | awk '{ print $1 }'`
if [ "${OPTIONS_CONN_MAX_WAIT_STATE}" = "" ]; then OPTIONS_CONN_MAX_WAIT_STATE="5000"; fi
logtext "Result: currently ${FIND} connections are in a waiting state (max configured: ${OPTIONS_CONN_MAX_WAIT_STATE})."
if [ ${FIND} -gt ${OPTIONS_CONN_MAX_WAIT_STATE} ]; then
Display --indent 2 --text "- Checking waiting connections" --result WARNING --color YELLOW
ReportSuggestion "${TEST_NO}" "Determine why system has many connections in WAIT state (${FIND})"
else
Display --indent 2 --text "- Checking waiting connections" --result OK --color GREEN
logtext "Result: ${FIND} connections are in WAIT state"
fi
fi
#
#################################################################################
#
# Test : NETW-3030
# Description : Checking for DHCP client
Register --test-no NETW-3030 --weight L --network NO --description "Checking DHCP client status"
if [ ${SKIPTEST} -eq 0 ]; then
IsRunning dhclient
if [ ${RUNNING} -eq 1 ]; then
Display --indent 2 --text "- Checking status DHCP client" --result RUNNING --color WHITE
DHCP_CLIENT_RUNNING=1
else
Display --indent 2 --text "- Checking status DHCP client" --result "NOT ACTIVE" --color WHITE
fi
fi
#
#################################################################################
#
report "dhcp_client_running=${DHCP_CLIENT_RUNNING}"
wait_for_keypress
#
#================================================================================
# Lynis - Copyright 2007-2015, Michael Boelen, CISOfy - https://cisofy.com