Philipp Deppenwiese merged this change.

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Approvals: build bot (Jenkins): Verified Patrick Rudolph: Looks good to me, approved
security/vboot: Enable TCPA log extension

* Implement TCPA log for tspi extend function.
* Hook tcpa_log_init into vboot tpm_setup function.
* Add TCPA log output for vboot GBB flags and HWID

Change-Id: I22b1aa8da1a95380c39715727615ce5ce4c9443f
Signed-off-by: Philipp Deppenwiese <zaolin@das-labor.org>
Reviewed-on: https://review.coreboot.org/27727
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
---
M src/security/tpm/tspi.h
M src/security/tpm/tspi/tspi.c
M src/security/vboot/secdata_tpm.c
3 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/src/security/tpm/tspi.h b/src/security/tpm/tspi.h
index 01b2984..43254c1 100644
--- a/src/security/tpm/tspi.h
+++ b/src/security/tpm/tspi.h
@@ -35,10 +35,12 @@
* Ask vboot for a digest and extend a TPM PCR with it.
* @param pcr sets the pcr index
* @param digest sets the hash to extend into the tpm
- * @param out_digest get extended hash
+ * @param digest_len the length of the digest
+ * @param name sets additional info where the digest comes from
* @return TPM_SUCCESS on success. If not a tpm error is returned
*/
-uint32_t tpm_extend_pcr(int pcr, uint8_t *digest, uint8_t *out_digest);
+uint32_t tpm_extend_pcr(int pcr, uint8_t *digest, size_t digest_len,
+ const char *name);

/**
* Issue a TPM_Clear and reenable/reactivate the TPM.
diff --git a/src/security/tpm/tspi/tspi.c b/src/security/tpm/tspi/tspi.c
index 407e1fa..48b6219 100644
--- a/src/security/tpm/tspi/tspi.c
+++ b/src/security/tpm/tspi/tspi.c
@@ -178,13 +178,21 @@
return TPM_SUCCESS;
}

-uint32_t tpm_extend_pcr(int pcr, uint8_t *digest, uint8_t *out_digest)
+uint32_t tpm_extend_pcr(int pcr, uint8_t *digest,
+ size_t digest_len, const char *name)
{
+ uint32_t result;
+
if (!digest)
return TPM_E_IOERROR;

- if (out_digest)
- return tlcl_extend(pcr, digest, out_digest);
+ result = tlcl_extend(pcr, digest, NULL);
+ if (result != TPM_SUCCESS)
+ return result;

- return tlcl_extend(pcr, digest, NULL);
+ result = tcpa_log_add_table_entry(name, pcr, digest, digest_len);
+ if (result != 0)
+ printk(BIOS_ERR, "ERROR: Couldn't create TCPA log entry\n");
+
+ return 0;
}
diff --git a/src/security/vboot/secdata_tpm.c b/src/security/vboot/secdata_tpm.c
index 57c107b..d3f4a11 100644
--- a/src/security/vboot/secdata_tpm.c
+++ b/src/security/vboot/secdata_tpm.c
@@ -61,11 +61,13 @@
} \
} while (0)

+#define TPM_PCR_GBB_FLAGS_NAME "GBB flags"
+#define TPM_PCR_GBB_HWID_NAME "GBB HWID"

static uint32_t safe_write(uint32_t index, const void *data, uint32_t length);

uint32_t vboot_extend_pcr(struct vb2_context *ctx, int pcr,
- enum vb2_pcr_digest which_digest)
+ enum vb2_pcr_digest which_digest)
{
uint8_t buffer[VB2_PCR_DIGEST_RECOMMENDED_SIZE];
uint32_t size = sizeof(buffer);
@@ -77,7 +79,15 @@
if (size < TPM_PCR_MINIMUM_DIGEST_SIZE)
return VB2_ERROR_UNKNOWN;

- return tpm_extend_pcr(pcr, buffer, NULL);
+ switch (which_digest) {
+ case BOOT_MODE_PCR:
+ return tpm_extend_pcr(pcr, buffer, size,
+ TPM_PCR_GBB_FLAGS_NAME);
+ case HWID_DIGEST_PCR:
+ return tpm_extend_pcr(pcr, buffer, size, TPM_PCR_GBB_HWID_NAME);
+ default:
+ return VB2_ERROR_UNKNOWN;
+ }
}

static uint32_t read_space_firmware(struct vb2_context *ctx)
@@ -441,6 +451,9 @@
if (result == TPM_E_MUST_REBOOT)
ctx->flags |= VB2_CONTEXT_SECDATA_WANTS_REBOOT;

+ // TCPA cbmem log
+ tcpa_log_init();
+
return result;
}


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Gerrit-Project: coreboot
Gerrit-Branch: master
Gerrit-MessageType: merged
Gerrit-Change-Id: I22b1aa8da1a95380c39715727615ce5ce4c9443f
Gerrit-Change-Number: 27727
Gerrit-PatchSet: 10
Gerrit-Owner: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Gerrit-Reviewer: Patrick Rudolph <siro@das-labor.org>
Gerrit-Reviewer: Paul Menzel <paulepanter@users.sourceforge.net>
Gerrit-Reviewer: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Gerrit-Reviewer: build bot (Jenkins) <no-reply@coreboot.org>