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[CRYP-7930] Modify to use 'lsblk' and 'cryptsetup' 

There are several challenges with the existing method of using
/etc/crypttab:

1)encrypted rootfs partitions are not typically listed in this
file (users are prompted for password in early boot instead)

2)the 'luks' option is the default option so it is possible for
/etc/crypttab entries to never have this set explicitly and any
block device configured as such will be missed currently

3)any device mounted manually, or using any other mechanism aside
from /etc/crypttab will be missed

This commit executes 'cryptsetup isLuks' on every block device in
the system to determine whether it is a LUKS device. This handles
all 3 cases mentioned above.

Test case wording was also updated to reflect the fact that it
only checks for LUKS entrypted block devices. So, plain dm-crypt
and TrueCrypt/VeraCrypt block device encryption is not detected.
Nor is any file system level encryption such as eCryptfs, EncFs,
gocryptfs.
This commit is contained in:
Julian Phillips 2019-07-17 16:18:12 -07:00
parent 2576bc8fca
commit 84dd024887
2 changed files with 16 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/binaries
View File

@ -141,6 +141,7 @@
cfagent) CFAGENTBINARY="${BINARY}"; FILE_INT_TOOL_FOUND=1; LogText " Found known binary: cfengine agent (configuration tool) - ${BINARY}" ;;
chkrootkit) CHKROOTKITBINARY="${BINARY}"; MALWARE_SCANNER_INSTALLED=1; LogText " Found known binary: chkrootkit (malware scanner) - ${BINARY}" ;;
comm) COMMBINARY="${BINARY}"; LogText " Found known binary: comm (file compare) - ${BINARY}" ;;
cryptsetup) CRYPTSETUPBINARY="${BINARY}"; LogText " Found known binary: cryptsetup (block device encryption) - ${BINARY}" ;;
csum) CSUMBINARY="${BINARY}"; LogText " Found known binary: csum (hashing tool on AIX) - ${BINARY}" ;;
curl) CURLBINARY="${BINARY}"; CURLVERSION=$(${BINARY} --version | grep "^curl" | awk '{ if ($1=="curl") { print $2 }}'); LogText " Found known binary: curl (browser, download utility) - ${BINARY}" ;;
cut) CUTBINARY="${BINARY}"; LogText " Found known binary: cut (text stream editor) - ${BINARY}" ;;
@ -186,6 +187,7 @@
logrotate) LOGROTATEBINARY="${BINARY}"; LogText " Found known binary: logrotate (log rotation tool) - ${BINARY}" ;;
ls) LSBINARY="${BINARY}"; LogText " Found known binary: ls (file listing) - ${BINARY}" ;;
lsattr) LSATTRBINARY="${BINARY}"; LogText " Found known binary: lsattr (file attributes) - ${BINARY}" ;;
lsblk) LSBLKBINARY="${BINARY}"; LogText " Found known binary: lsblk (block devices) - ${BINARY}" ;;
lsmod) LSMODBINARY="${BINARY}"; LogText " Found known binary: lsmod (kernel modules) - ${BINARY}" ;;
lsof) LSOFBINARY="${BINARY}"; LogText " Found known binary: lsof (open files) - ${BINARY}" ;;
lsvg) LSVGBINARY=${BINARY}; LogText " Found known binary: lsvg (volume manager) - ${BINARY}" ;;

34
include/tests_crypto
View File

@ -126,34 +126,28 @@
ReportSuggestion ${TEST_NO} "Check available certificates for expiration"
fi
fi
#
#################################################################################
#
# Test : CRYP-7930
# Description : Determine if system uses disk or file encryption
Register --test-no CRYP-7930 --weight L --network NO --category security --description "Determine if system uses disk or file encryption"
# Description : Determine if system uses LUKS block device encryption
if [ ! "${LSBLKBINARY}" = "" -a ! "${CRYPTSETUPBINARY}" = "" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no CRYP-7930 --preqs-met ${PREQS_MET} --weight L --network NO --root-only YES --category security --description "Determine if system uses LUKS block device encryption"
if [ ${SKIPTEST} -eq 0 ]; then
FILE="${ROOTDIR}etc/crypttab"
if [ -f ${FILE} ]; then
LogText "Result: crypttab file (${FILE}) exists"
DATA=$(${GREPBINARY} "^[a-z]" ${FILE} | ${TRBINARY} -cd '[:alnum:]_\-=,\n\t ' | ${SEDBINARY} 's/[[:blank:]]/__space__/g')
for LINE in ${DATA}; do
LINE=$(echo ${LINE} | ${SEDBINARY} 's/__space__/ /g')
if ContainsString "luks," "${LINE}"; then
PARTITION=$(echo ${LINE} | ${AWKBINARY} '{print $1}' | ${AWKBINARY} -F_ '{print $1}')
LogText "Result: Found LUKS encryption on partition ${PARTITION}"
Report "encryption[]=luks,partition,${PARTITION}"
fi
done
unset DATA LINE PARTITION
else
LogText "Result: crypttab file (${FILE}) does not exist"
fi
FOUND=0
for BLOCK_DEV in $(${LSBLKBINARY} --noheadings -o PATH); do
if ${CRYPTSETUPBINARY} isLuks ${BLOCK_DEV}; then
LogText "Result: Found LUKS encrypted block device: ${BLOCK_DEV}"
Report "encryption[]=luks,block_device,${BLOCK_DEV}"
((FOUND++))
fi
done
Display --indent 2 --text "- Found ${FOUND} LUKS encrypted block devices." --result OK --color WHITE
unset BLOCK_DEV
fi
#
#################################################################################
#
WaitForKeyPress
#