4 # check_clamav_signatures - Nagios plugin to monitor ClamAV signatures are up to date.
6 # Released under the MIT License.
8 # https://github.com/tommarshall/nagios-check-clamav-signatures
16 CLAM_LIB_DIR=/var/lib/clamav
17 NUMERICAL_REGEX='^[0-9]+$'
24 echo "check_clamav_signatures $VERSION"
28 # Output usage information.
32 echo 'Usage: ./check_clamav_signatures [options]'
36 # Output help information.
44 ./check_clamav_signatures
47 -p, --path <path> path to ClamAV lib directory, if not $CLAM_LIB_DIR
48 -V, --version output version
49 -h, --help output help information
51 For more information, see https://github.com/tommarshall/nagios-check-clamav-signatures
60 while test $# -ne 0; do
63 -p|--path) CLAM_LIB_DIR=$1; shift ;;
64 -V|--version) version; exit ;;
65 -h|--help) help; exit ;;
67 echo "UNKNOWN: Unrecognised argument: $ARG"
78 # ensure we have executable dependencies
79 for dependency in cut host grep sigtool sed; do
80 if ! hash $dependency >/dev/null 2>&1; then
81 echo "UNKNOWN: Missing dependency: ${dependency}"
86 # ensure the clam lib dir exists
87 if [ ! -d "$CLAM_LIB_DIR" ]; then
88 echo "UNKNOWN: Unable to locate ClamAV lib directory"
92 # ensure we have a daily signatures file
93 if [ -e ${CLAM_LIB_DIR}/daily.cld ]; then
94 DAILY_SIGNATURES_PATH="${CLAM_LIB_DIR}/daily.cld"
95 elif [ -e ${CLAM_LIB_DIR}/daily.cvd ]; then
96 DAILY_SIGNATURES_PATH="${CLAM_LIB_DIR}/daily.cvd"
98 echo "UNKNOWN: Unable to locate installed daily signatures"
102 # ensure we have a main signatures file
103 if [ -e ${CLAM_LIB_DIR}/main.cvd ]; then
104 MAIN_SIGNATURES_PATH="${CLAM_LIB_DIR}/main.cvd"
105 elif [ -e ${CLAM_LIB_DIR}/main.cld ]; then
106 MAIN_SIGNATURES_PATH="${CLAM_LIB_DIR}/main.cld"
108 echo "UNKNOWN: Unable to locate installed main signatures"
112 # extract the daily signatures version
113 INSTALLED_DAILY_VERSION=$(sigtool -i ${DAILY_SIGNATURES_PATH} 2>/dev/null | grep Version | sed -e 's/Version: //')
114 if ! [[ $INSTALLED_DAILY_VERSION =~ $NUMERICAL_REGEX ]]; then
115 echo "UNKNOWN: Unable to establish installed daily signatures version"
119 # extract the main signatures version
120 INSTALLED_MAIN_VERSION=$(sigtool -i ${MAIN_SIGNATURES_PATH} 2>/dev/null | grep Version | sed -e 's/Version: //')
121 if ! [[ $INSTALLED_MAIN_VERSION =~ $NUMERICAL_REGEX ]]; then
122 echo "UNKNOWN: Unable to establish installed main signatures version"
126 # query the DNS record
127 DNS_TXT_RECORD=$(host -t txt current.cvd.clamav.net)
128 if [ $? -ne 0 ]; then
129 echo "UNKNOWN: DNS query to current.cvd.clamav.net failed"
133 # extract the current daily signatures version from the DNS TXT record
134 CURRENT_DAILY_VERSION=$(echo $DNS_TXT_RECORD | cut -d : -f 3)
135 if ! [[ $CURRENT_DAILY_VERSION =~ $NUMERICAL_REGEX ]]; then
136 echo "UNKNOWN: Unable to establish current daily signatures version from DNS query"
140 # extract the current main signatures version from the DNS TXT record
141 CURRENT_MAIN_VERSION=$(echo $DNS_TXT_RECORD | cut -d : -f 2)
142 if ! [[ $CURRENT_MAIN_VERSION =~ $NUMERICAL_REGEX ]]; then
143 echo "UNKNOWN: Unable to establish current main signatures version from DNS query"
147 # determine the difference between the current and installed versions
148 DAILY_VERSION_DELTA=$((CURRENT_DAILY_VERSION-INSTALLED_DAILY_VERSION))
149 MAIN_VERSION_DELTA=$((CURRENT_MAIN_VERSION-INSTALLED_MAIN_VERSION))
151 if [ $DAILY_VERSION_DELTA -gt 0 -o $MAIN_VERSION_DELTA -gt 0 ]; then
152 echo "CRITICAL: Signatures expired;" \
153 "daily version: ${INSTALLED_DAILY_VERSION} (${DAILY_VERSION_DELTA} behind)," \
154 "main version: ${INSTALLED_MAIN_VERSION} (${MAIN_VERSION_DELTA} behind)"
158 echo "OK: Signatures up to date;"\
159 "daily version: ${INSTALLED_DAILY_VERSION}," \
160 "main version: ${INSTALLED_MAIN_VERSION}"