for TPM 2.0 and support more evmctl versions. Because exporting PCR registers for TPM 2.0 has not been upstreamed [1], we use user space code, which requires evmctl >= 1.3.1 and tsspcrread. Using evmctl allows to test for TPM devices which does not export event log (/sys/kernel/security/tpm0/binary_bios_measurements). For TPM 1.2 read tpm0 device pcrs file from kernel. (tss1pcrread could be also used, but it's not yet packaged by distros.) For old kernels which use SHA1/MD5, any evmctl version is required (evmctl ima_measurement was introduced in very old v0.7), but * newer sysctl path /sys/class/tpm/tpm0/device/pcrs requires evmctl 1.1 * using ima_policy=tcb requires 1.3.1 due --ignore-violations We now support output format of ima_measurement command for various evmctl versions: * 1.3: "sha256: TPM PCR-10:" (or other algorithm, e.g. "sha1:") * 1.1-1.2.1: "HW PCR-10:" (the only previously supported format) * 0.7-1.0: "PCR-10:" NOTE: we ignore evmctl failure for evmctl < 1.3.1 (missing --ignore-violations, also evmctl < 1.1 fails with "PCRAgg does not match PCR-10") [1] https://patchwork.kernel.org/patch/11759729/ Signed-off-by: Petr Vorel <pvorel@xxxxxxx> --- changes v3->v4: * use --ignore-violations if evmctl >= 1.3.1 available * check error only for 1.3.1, for others check only the result * check for ima_policy=tcb (or ima_tcb) and require 1.3.1 if used (to get --ignore-violations) .../security/integrity/ima/tests/ima_setup.sh | 14 +- .../security/integrity/ima/tests/ima_tpm.sh | 151 +++++++++++++----- 2 files changed, 118 insertions(+), 47 deletions(-) diff --git a/testcases/kernel/security/integrity/ima/tests/ima_setup.sh b/testcases/kernel/security/integrity/ima/tests/ima_setup.sh index 83ea62d4f..b801c4371 100644 --- a/testcases/kernel/security/integrity/ima/tests/ima_setup.sh +++ b/testcases/kernel/security/integrity/ima/tests/ima_setup.sh @@ -93,7 +93,7 @@ require_ima_policy_content() fi } -require_ima_policy_cmdline() +check_ima_policy_cmdline() { local policy="$1" local i @@ -101,10 +101,18 @@ require_ima_policy_cmdline() grep -q "ima_$policy" /proc/cmdline && return for i in $(cat /proc/cmdline); do if echo "$i" | grep -q '^ima_policy='; then - echo "$i" | grep -q -e "|[ ]*$policy" -e "$policy[ ]*|" -e "=$policy" && return + echo "$i" | grep -q -e "|[ ]*$policy" -e "$policy[ ]*|" -e "=$policy" && return 0 fi done - tst_brk TCONF "IMA measurement tests require builtin IMA $policy policy (e.g. ima_policy=$policy kernel parameter)" + return 1 +} + +require_ima_policy_cmdline() +{ + local policy="$1" + + check_ima_policy_cmdline $policy || \ + tst_brk TCONF "IMA measurement tests require builtin IMA $policy policy (e.g. ima_policy=$policy kernel parameter)" } mount_helper() diff --git a/testcases/kernel/security/integrity/ima/tests/ima_tpm.sh b/testcases/kernel/security/integrity/ima/tests/ima_tpm.sh index ce35a8e27..43d330802 100755 --- a/testcases/kernel/security/integrity/ima/tests/ima_tpm.sh +++ b/testcases/kernel/security/integrity/ima/tests/ima_tpm.sh @@ -13,7 +13,8 @@ TST_SETUP="setup" . ima_setup.sh EVMCTL_REQUIRED='1.3.1' -ERRMSG_EVMCTL="install evmctl >= $EVMCTL_REQUIRED" +ERRMSG_EVMCTL="=> install evmctl >= $EVMCTL_REQUIRED" +ERRMSG_TPM="TPM hardware support not enabled in kernel or no TPM chip found" setup() { @@ -101,11 +102,91 @@ get_tpm_version() fi } +read_pcr_tpm1() +{ + local pcr_path="/sys/class/tpm/tpm0/device/pcrs" + local evmctl_required="1.1" + local pcr hash + + if [ ! -f "$pcrs_path" ]; then + pcrs_path="/sys/class/misc/tpm0/device/pcrs" + elif ! check_evmctl $evmctl_required; then + tst_res TCONF "evmctl >= $evmctl_required required" + return 1 + fi + + if [ ! -f "$pcr_path" ]; then + tst_res TCONF "missing PCR file $pcrs_path ($ERRMSG_TPM)" + return + fi + + while read line; do + pcr="$(echo $line | cut -d':' -f1)" + hash="$(echo $line | cut -d':' -f2 | awk '{ gsub (" ", "", $0); print tolower($0) }')" + echo "$pcr: $hash" + done < $pcr_path +} + +# NOTE: TPM 1.2 would require to use tss1pcrread which is not fully adopted +# by distros yet. +read_pcr_tpm2() +{ + local pcrmax=23 + local pcrread="tsspcrread -halg $ALGORITHM" + local i pcr + + tst_check_cmds tsspcrread || return 1 + + for i in $(seq 0 $pcrmax); do + pcr=$($pcrread -ha "$i" -ns) + if [ $? -ne 0 ]; then + tst_brk TBROK "tsspcrread failed: $pcr" + fi + printf "PCR-%02d: %s\n" $i "$pcr" + done +} + +get_pcr10_aggregate() +{ + local params pcr + local msg="$ERRMSG_EVMCTL" + local res=TCONF + + if [ -z "$MISSING_EVMCTL" ]; then + params="--ignore-violations" + msg= + res=TFAIL + elif check_ima_policy_cmdline "tcb"; then + tst_res TCONF "using builtin IMA TCB policy $ERRMSG_EVMCTL" + return + fi + + evmctl -v ima_measurement $params $BINARY_MEASUREMENTS > hash.txt 2>&1 + if [ $? -ne 0 -a -z "$MISSING_EVMCTL" ]; then + tst_res TFAIL "evmctl failed $ERRMSG_EVMCTL" + tst_res TINFO "hash file:" + cat hash.txt >&2 + return + fi + + pcr=$(grep -E "^($ALGORITHM: )*PCRAgg.*:" hash.txt \ + | awk '{print $NF}') + + if [ -z "$pcr" ]; then + tst_res $res "failed to find aggregate PCR-10 $msg" + tst_res TINFO "hash file:" + cat hash.txt >&2 + return + fi + + echo "$pcr" +} + test1_virtual_tpm() { local zero=$(echo $DIGEST | awk '{gsub(/./, "0")}; {print}') - tst_res TINFO "TPM hardware support not enabled in kernel or no TPM chip found, testing TPM-bypass" + tst_res TINFO "$ERRMSG_TPM, testing TPM-bypass" if [ "$DIGEST" = "$zero" ]; then tst_res TPASS "bios boot aggregate is $zero" @@ -122,7 +203,7 @@ test1_hw_tpm() if [ "$MISSING_EVMCTL" = 1 ]; then if [ ! -f "$tpm_bios" ]; then - tst_res TCONF "missing $tpm_bios, $ERRMSG_EVMCTL" + tst_res TCONF "missing $tpm_bios $ERRMSG_EVMCTL" return fi tst_check_cmds ima_boot_aggregate || return @@ -151,57 +232,39 @@ test1() [ -z "$TPM_VERSION" ] && test1_virtual_tpm || test1_hw_tpm } -# Probably cleaner to programmatically read the PCR values directly -# from the TPM, but that would require a TPM library. For now, use -# the PCR values from /sys/devices. -validate_pcr() +test2() { - tst_res TINFO "verify PCR (Process Control Register)" + local hash pcr_aggregate - local dev_pcrs="$1" - local pcr hash aggregate_pcr + tst_res TINFO "verify PCR values" - aggregate_pcr="$(evmctl -v ima_measurement $BINARY_MEASUREMENTS 2>&1 | \ - grep 'HW PCR-10:' | awk '{print $3}')" - if [ -z "$aggregate_pcr" ]; then - tst_res TFAIL "failed to get PCR-10" - return 1 + if [ -z "$TPM_VERSION" ]; then + tst_brk TCONF "TMP version not detected ($ERRMSG_TPM)" fi - while read line; do - pcr="$(echo $line | cut -d':' -f1)" - if [ "$pcr" = "PCR-10" ]; then - hash="$(echo $line | cut -d':' -f2 | awk '{ gsub (" ", "", $0); print tolower($0) }')" - [ "$hash" = "$aggregate_pcr" ] - return $? - fi - done < $dev_pcrs - return 1 -} - -test2() -{ - tst_res TINFO "verify PCR values" - tst_check_cmds evmctl || return + if [ "$ALGORITHM" = "sha1" -a "$MISSING_EVMCTL" = 1 ]; then + tst_check_cmds evmctl || return 1 + fi - tst_res TINFO "evmctl version: $(evmctl --version)" + read_pcr_tpm$TPM_VERSION > pcr.txt || return + hash=$(grep "^PCR-10" pcr.txt | cut -d' ' -f2) + if [ -z "$hash" ]; then + tst_res TFAIL "PCR-10 hash not found" + cat pcr.txt + return + fi + tst_res TINFO "real PCR-10: '$hash'" - local pcrs_path="/sys/class/tpm/tpm0/device/pcrs" - if [ -f "$pcrs_path" ]; then - tst_res TINFO "new PCRS path, evmctl >= 1.1 required" - else - pcrs_path="/sys/class/misc/tpm0/device/pcrs" + pcr_aggregate="$(get_pcr10_aggregate)" + if [ -z "$pcr_aggregate" ]; then + return fi + tst_res TINFO "aggregate PCR-10: '$hash'" - if [ -f "$pcrs_path" ]; then - validate_pcr $pcrs_path - if [ $? -eq 0 ]; then - tst_res TPASS "aggregate PCR value matches real PCR value" - else - tst_res TFAIL "aggregate PCR value does not match real PCR value" - fi + if [ "$hash" = "$pcr_aggregate" ]; then + tst_res TPASS "aggregate PCR value matches real PCR value" else - tst_res TCONF "TPM Hardware Support not enabled in kernel or no TPM chip found" + tst_res TFAIL "aggregate PCR value does not match real PCR value" fi } -- 2.28.0
