Add a testcase that verifies that the IMA subsystem has correctly measured keys added to keyrings specified in the IMA policy file. Additionally, add support for handling a new IMA template descriptor, namely ima-buf[1], in the IMA measurement tests. [1]: https://www.kernel.org/doc/html/latest/security/IMA-templates.html#use Signed-off-by: Lachlan Sneff <t-josne@xxxxxxxxxxxxxxxxxxx> --- runtest/ima | 1 + .../integrity/ima/tests/compute_digest.sh | 38 ++++++++++ .../security/integrity/ima/tests/ima_keys.sh | 72 +++++++++++++++++++ .../integrity/ima/tests/ima_measurements.sh | 37 +--------- 4 files changed, 113 insertions(+), 35 deletions(-) create mode 100644 testcases/kernel/security/integrity/ima/tests/compute_digest.sh create mode 100644 testcases/kernel/security/integrity/ima/tests/ima_keys.sh diff --git a/runtest/ima b/runtest/ima index f3ea88cf0..939fb40f0 100644 --- a/runtest/ima +++ b/runtest/ima @@ -4,3 +4,4 @@ ima_policy ima_policy.sh ima_tpm ima_tpm.sh ima_violations ima_violations.sh evm_overlay evm_overlay.sh +ima_keys ima_keys.sh diff --git a/testcases/kernel/security/integrity/ima/tests/compute_digest.sh b/testcases/kernel/security/integrity/ima/tests/compute_digest.sh new file mode 100644 index 000000000..85f6bf3da --- /dev/null +++ b/testcases/kernel/security/integrity/ima/tests/compute_digest.sh @@ -0,0 +1,38 @@ +# SPDX-License-Identifier: GPL-2.0-or-later +# Copyright (c) 2009 IBM Corporation +# Copyright (c) 2018-2020 Petr Vorel <pvorel@xxxxxxx> +# Author: Mimi Zohar <zohar@xxxxxxxxxxxxx> + +# TODO: find support for rmd128 rmd256 rmd320 wp256 wp384 tgr128 tgr160 +compute_digest() +{ + local algorithm="$1" + local file="$2" + local digest + + digest="$(${algorithm}sum $file 2>/dev/null | cut -f1 -d ' ')" + if [ -n "$digest" ]; then + echo "$digest" + return 0 + fi + + digest="$(openssl $algorithm $file 2>/dev/null | cut -f2 -d ' ')" + if [ -n "$digest" ]; then + echo "$digest" + return 0 + fi + + # uncommon ciphers + local arg="$algorithm" + case "$algorithm" in + tgr192) arg="tiger" ;; + wp512) arg="whirlpool" ;; + esac + + digest="$(rdigest --$arg $file 2>/dev/null | cut -f1 -d ' ')" + if [ -n "$digest" ]; then + echo "$digest" + return 0 + fi + return 1 +} diff --git a/testcases/kernel/security/integrity/ima/tests/ima_keys.sh b/testcases/kernel/security/integrity/ima/tests/ima_keys.sh new file mode 100644 index 000000000..1b0dd0aed --- /dev/null +++ b/testcases/kernel/security/integrity/ima/tests/ima_keys.sh @@ -0,0 +1,72 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0-or-later +# Copyright (c) 2020 Microsoft Corporation +# Author: Lachlan Sneff <t-josne@xxxxxxxxxxxxxxxxxxx> +# +# Verify that keys are measured correctly based on policy. + +TST_NEEDS_CMDS="awk cut" +TST_SETUP="setup" +TST_CNT=1 +TST_NEEDS_DEVICE=1 + +. ima_setup.sh +. compute_digest.sh + +setup() +{ + TEST_FILE="$PWD/test.txt" +} + +# Based on https://lkml.org/lkml/2019/12/13/564. +test1() +{ + local keyrings keycheck_line templates + + tst_res TINFO "verifying key measurement for keyrings and \ +templates specified in ima policy file" + + IMA_POLICY="$IMA_DIR/policy" + [ -f $IMA_POLICY ] || tst_brk TCONF "missing $IMA_POLICY" + + keycheck_line=$(grep "func=KEY_CHECK" $IMA_POLICY) + if [ -z "$keycheck_line" ]; then + tst_brk TCONF "ima policy does not specify \"func=KEY_CHECK\"" + fi + + if echo "$keycheck_line" | grep -q "*keyrings*"; then + tst_brk TCONF "ima policy does not specify a keyrings to check" + fi + + keyrings=$(echo "$keycheck_line" | tr " " "\n" | grep "keyrings" | \ + sed "s/\./\\\./g" | cut -d'=' -f2) + if [ -z "$keyrings" ]; then + tst_brk TCONF "ima policy has a keyring key-value specifier, \ +but no specified keyrings" + fi + + templates=$(echo "$keycheck_line" | tr " " "\n" | grep "template" | \ + cut -d'=' -f2) + + grep -E "($templates)*($keyrings)" $ASCII_MEASUREMENTS | while read line + do + local digest expected_digest algorithm + + digest=$(echo "$line" | cut -d' ' -f4 | cut -d':' -f2) + algorithm=$(echo "$line" | cut -d' ' -f4 | cut -d':' -f1) + + echo "$line" | cut -d' ' -f6 | xxd -r -p > $TEST_FILE + + expected_digest="$(compute_digest $algorithm $TEST_FILE)" || \ + tst_brk TCONF "cannot compute digest for $algorithm" + + if [ "$digest" != "$expected_digest" ]; then + tst_res TFAIL "incorrect digest was found for the \ +$(echo "$line" | cut -d' ' -f5) keyring" + fi + done + + tst_res TPASS "specified keyrings were measured correctly" +} + +tst_run diff --git a/testcases/kernel/security/integrity/ima/tests/ima_measurements.sh b/testcases/kernel/security/integrity/ima/tests/ima_measurements.sh index 54237d688..0a58d021d 100755 --- a/testcases/kernel/security/integrity/ima/tests/ima_measurements.sh +++ b/testcases/kernel/security/integrity/ima/tests/ima_measurements.sh @@ -12,6 +12,7 @@ TST_CNT=3 TST_NEEDS_DEVICE=1 . ima_setup.sh +. compute_digest.sh setup() { @@ -28,7 +29,7 @@ setup() # parse digest index # https://www.kernel.org/doc/html/latest/security/IMA-templates.html#use case "$template" in - ima|ima-ng|ima-sig) DIGEST_INDEX=4 ;; + ima|ima-ng|ima-sig|ima-buf) DIGEST_INDEX=4 ;; *) # using ima_template_fmt kernel parameter local IFS="|" @@ -46,40 +47,6 @@ setup() "Cannot find digest index (template: '$template')" } -# TODO: find support for rmd128 rmd256 rmd320 wp256 wp384 tgr128 tgr160 -compute_digest() -{ - local algorithm="$1" - local file="$2" - local digest - - digest="$(${algorithm}sum $file 2>/dev/null | cut -f1 -d ' ')" - if [ -n "$digest" ]; then - echo "$digest" - return 0 - fi - - digest="$(openssl $algorithm $file 2>/dev/null | cut -f2 -d ' ')" - if [ -n "$digest" ]; then - echo "$digest" - return 0 - fi - - # uncommon ciphers - local arg="$algorithm" - case "$algorithm" in - tgr192) arg="tiger" ;; - wp512) arg="whirlpool" ;; - esac - - digest="$(rdigest --$arg $file 2>/dev/null | cut -f1 -d ' ')" - if [ -n "$digest" ]; then - echo "$digest" - return 0 - fi - return 1 -} - ima_check() { local delimiter=':' -- 2.25.1
