diff options
| author | Ruchika Gupta <ruchika.gupta@linaro.org> | 2021-11-29 10:39:45 +0300 |
|---|---|---|
| committer | Heinrich Schuchardt <heinrich.schuchardt@canonical.com> | 2021-11-30 11:23:49 +0300 |
| commit | 2957a1e22407a84a2cc7c4ea5a8136af1d0278d9 (patch) | |
| tree | 7f4cc42de253c761e6d94906a6f777e3216b8174 | |
| parent | 34287efdaf6ed186a64445f65227b5407a1dcd63 (diff) | |
| download | u-boot-2957a1e22407a84a2cc7c4ea5a8136af1d0278d9.tar.xz | |
tpm: use more algorithms than sha256 on pcr_read
The current tpm2_pcr_read is hardcoded using SHA256. Make the
actual command to TPM configurable to use wider range of algorithms.
The current command line is kept as is i.e limited to SHA-256 only.
Signed-off-by: Ruchika Gupta <ruchika.gupta@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
| -rw-r--r-- | cmd/tpm-v2.c | 3 | ||||
| -rw-r--r-- | include/tpm-v2.h | 5 | ||||
| -rw-r--r-- | lib/tpm-v2.c | 12 |
3 files changed, 14 insertions, 6 deletions
diff --git a/cmd/tpm-v2.c b/cmd/tpm-v2.c index daae91100a..4ea5f9f094 100644 --- a/cmd/tpm-v2.c +++ b/cmd/tpm-v2.c @@ -151,7 +151,8 @@ 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, data, &updates); + rc = tpm2_pcr_read(dev, index, priv->pcr_select_min, TPM2_ALG_SHA256, + data, TPM2_DIGEST_LEN, &updates); if (!rc) { printf("PCR #%u content (%u known updates):\n", index, updates); print_byte_string(data, TPM2_DIGEST_LEN); diff --git a/include/tpm-v2.h b/include/tpm-v2.h index ceff7d245e..4e9dd52cb6 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -512,13 +512,16 @@ u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data, * @dev TPM device * @idx Index of the PCR * @idx_min_sz Minimum size in bytes of the pcrSelect array + * @algorithm Algorithm used, defined in 'enum tpm2_algorithms' * @data Output buffer for contents of the named PCR + * @digest_len len of the data * @updates Optional out parameter: number of updates for this PCR * * @return code of the operation */ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz, - void *data, unsigned int *updates); + u16 algorithm, void *data, u32 digest_len, + unsigned int *updates); /** * Issue a TPM2_GetCapability command. This implementation is limited diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c index 2e7b27bd6b..1bf627853a 100644 --- a/lib/tpm-v2.c +++ b/lib/tpm-v2.c @@ -254,7 +254,8 @@ u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data, } u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz, - void *data, unsigned int *updates) + u16 algorithm, void *data, u32 digest_len, + unsigned int *updates) { u8 idx_array_sz = max(idx_min_sz, DIV_ROUND_UP(idx, 8)); u8 command_v2[COMMAND_BUFFER_SIZE] = { @@ -264,7 +265,7 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz, /* TPML_PCR_SELECTION */ tpm_u32(1), /* Number of selections */ - tpm_u16(TPM2_ALG_SHA256), /* Algorithm of the hash */ + tpm_u16(algorithm), /* Algorithm of the hash */ idx_array_sz, /* Array size for selection */ /* bitmap(idx) Selected PCR bitmap */ }; @@ -283,10 +284,13 @@ u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz, if (ret) return ret; + if (digest_len > response_len) + return TPM_LIB_ERROR; + if (unpack_byte_string(response, response_len, "ds", 10, &counter, - response_len - TPM2_DIGEST_LEN, data, - TPM2_DIGEST_LEN)) + response_len - digest_len, data, + digest_len)) return TPM_LIB_ERROR; if (updates) |