From: Tim Harvey <tharvey@gateworks.com>
Date: Sat, 25 May 2024 20:00:49 +0000 (-0700)
Subject: tpm-v2: allow algorithm name to be configured for pcr_read and pcr_extend
X-Git-Tag: v2025.01-rc5-pxa1908~468^2
X-Git-Url: http://git.dujemihanovic.xyz/img/static//%22brlog.php?a=commitdiff_plain;h=89aa8463cdf3919ca4f04fc24ec8b154ff56d97e;p=u-boot.git
tpm-v2: allow algorithm name to be configured for pcr_read and pcr_extend
For pcr_read and pcr_extend commands allow the digest algorithm to be
specified by an additional argument. If not specified it will default to
SHA256 for backwards compatibility.
Additionally update test_tpm2.py for the changes in output in pcr_read
which now shows the algo and algo length in the output.
A follow-on to this could be to extend all PCR banks with the detected
algo when the <digest_algo> argument is 'auto'.
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
---
diff --git a/cmd/tpm-v2.c b/cmd/tpm-v2.c
index 7e479b9dfe..2343b4d9cb 100644
--- a/cmd/tpm-v2.c
+++ b/cmd/tpm-v2.c
@@ -99,11 +99,19 @@ static int do_tpm2_pcr_extend(struct cmd_tbl *cmdtp, int flag, int argc,
struct tpm_chip_priv *priv;
u32 index = simple_strtoul(argv[1], NULL, 0);
void *digest = map_sysmem(simple_strtoul(argv[2], NULL, 0), 0);
+ int algo = TPM2_ALG_SHA256;
+ int algo_len;
int ret;
u32 rc;
- if (argc != 3)
+ if (argc < 3 || argc > 4)
return CMD_RET_USAGE;
+ if (argc == 4) {
+ algo = tpm2_name_to_algorithm(argv[3]);
+ if (algo < 0)
+ return CMD_RET_FAILURE;
+ }
+ algo_len = tpm2_algorithm_to_len(algo);
ret = get_tpm(&dev);
if (ret)
@@ -116,8 +124,12 @@ static int do_tpm2_pcr_extend(struct cmd_tbl *cmdtp, int flag, int argc,
if (index >= priv->pcr_count)
return -EINVAL;
- rc = tpm2_pcr_extend(dev, index, TPM2_ALG_SHA256, digest,
- TPM2_DIGEST_LEN);
+ rc = tpm2_pcr_extend(dev, index, algo, digest, algo_len);
+ if (!rc) {
+ printf("PCR #%u extended with %d byte %s digest\n", index,
+ algo_len, tpm2_algorithm_name(algo));
+ print_byte_string(digest, algo_len);
+ }
unmap_sysmem(digest);
@@ -127,15 +139,23 @@ static int do_tpm2_pcr_extend(struct cmd_tbl *cmdtp, int flag, int argc,
static int do_tpm_pcr_read(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
+ enum tpm2_algorithms algo = TPM2_ALG_SHA256;
struct udevice *dev;
struct tpm_chip_priv *priv;
u32 index, rc;
+ int algo_len;
unsigned int updates;
void *data;
int ret;
- if (argc != 3)
+ if (argc < 3 || argc > 4)
return CMD_RET_USAGE;
+ if (argc == 4) {
+ algo = tpm2_name_to_algorithm(argv[3]);
+ if (algo < 0)
+ return CMD_RET_FAILURE;
+ }
+ algo_len = tpm2_algorithm_to_len(algo);
ret = get_tpm(&dev);
if (ret)
@@ -151,11 +171,12 @@ static int do_tpm_pcr_read(struct cmd_tbl *cmdtp, int flag, int argc,
data = map_sysmem(simple_strtoul(argv[2], NULL, 0), 0);
- rc = tpm2_pcr_read(dev, index, priv->pcr_select_min, TPM2_ALG_SHA256,
- data, TPM2_DIGEST_LEN, &updates);
+ rc = tpm2_pcr_read(dev, index, priv->pcr_select_min, algo,
+ data, algo_len, &updates);
if (!rc) {
- printf("PCR #%u content (%u known updates):\n", index, updates);
- print_byte_string(data, TPM2_DIGEST_LEN);
+ printf("PCR #%u %s %d byte content (%u known updates):\n", index,
+ tpm2_algorithm_name(algo), algo_len, updates);
+ print_byte_string(data, algo_len);
}
unmap_sysmem(data);
@@ -415,14 +436,14 @@ U_BOOT_CMD(tpm2, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command",
" <hierarchy> is one of:\n"
" * TPM2_RH_LOCKOUT\n"
" * TPM2_RH_PLATFORM\n"
-"pcr_extend <pcr> <digest_addr>\n"
-" Extend PCR #<pcr> with digest at <digest_addr>.\n"
+"pcr_extend <pcr> <digest_addr> [<digest_algo>]\n"
+" Extend PCR #<pcr> with digest at <digest_addr> with digest_algo.\n"
" <pcr>: index of the PCR\n"
-" <digest_addr>: address of a 32-byte SHA256 digest\n"
-"pcr_read <pcr> <digest_addr>\n"
-" Read PCR #<pcr> to memory address <digest_addr>.\n"
+" <digest_addr>: address of digest of digest_algo type (defaults to SHA256)\n"
+"pcr_read <pcr> <digest_addr> [<digest_algo>]\n"
+" Read PCR #<pcr> to memory address <digest_addr> with <digest_algo>.\n"
" <pcr>: index of the PCR\n"
-" <digest_addr>: address to store the a 32-byte SHA256 digest\n"
+" <digest_addr>: address of digest of digest_algo type (defaults to SHA256)\n"
"get_capability <capability> <property> <addr> <count>\n"
" Read and display <count> entries indexed by <capability>/<property>.\n"
" Values are 4 bytes long and are written at <addr>.\n"
diff --git a/test/py/tests/test_tpm2.py b/test/py/tests/test_tpm2.py
index 1d654cd4a2..75f5d31fc6 100644
--- a/test/py/tests/test_tpm2.py
+++ b/test/py/tests/test_tpm2.py
@@ -257,7 +257,7 @@ def test_tpm2_pcr_read(u_boot_console):
updates = int(re.findall(r'\d+', str)[0])
# Check the output value
- assert 'PCR #10 content' in read_pcr
+ assert 'PCR #10 sha256 32 byte content' in read_pcr
assert '00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00' in read_pcr
@pytest.mark.buildconfigspec('cmd_tpm_v2')