diff options
| author | Julius Werner <jwerner@chromium.org> | 2015-01-30 18:45:27 -0800 |
|---|---|---|
| committer | Aaron Durbin <adurbin@chromium.org> | 2015-04-20 17:06:28 +0200 |
| commit | 76e3303290f7f17d5318e87321567188f165cc2a (patch) | |
| tree | 43efe41ca19f18bb4f96899b91a86da221fb0a70 /src/vendorcode/google | |
| parent | 5aecacca053c3ce8bdb7b8ce94473703b3240e37 (diff) | |
| download | coreboot-76e3303290f7f17d5318e87321567188f165cc2a.tar.xz | |
chromeos: vboot2: Add TPM PCR extension support
ChromeOS/vboot devices expect the TPM PCRs 0 and 1 to be extended with
digests that attest the chosen boot mode (developer/recovery) and the
HWID in a secure way. This patch uses the newly added vboot2 support
functions to fetch these digests and store them in the TPM.
CQ-DEPEND=CL:244542
BRANCH=veyron
BUG=chromium:451609
TEST=Booted Jerry. Confirmed that PCR0 contains the same value as on my
vboot1 Blaze and Falco (and PCR1 contains some non-zero hash).
Original-Change-Id: I7037b8198c09fccee5440c4c85f0821166784cec
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/245119
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>
(cherry picked from commit 8b44e13098cb7493091f2ce6c4ab423f2cbf0177)
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Change-Id: I549de8c07353683633fbf73e4ee62ba0ed72ff89
Reviewed-on: http://review.coreboot.org/9706
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Diffstat (limited to 'src/vendorcode/google')
| -rw-r--r-- | src/vendorcode/google/chromeos/vboot2/antirollback.c | 17 | ||||
| -rw-r--r-- | src/vendorcode/google/chromeos/vboot2/verstage.c | 15 |
2 files changed, 32 insertions, 0 deletions
diff --git a/src/vendorcode/google/chromeos/vboot2/antirollback.c b/src/vendorcode/google/chromeos/vboot2/antirollback.c index f420d16114..407b19cecd 100644 --- a/src/vendorcode/google/chromeos/vboot2/antirollback.c +++ b/src/vendorcode/google/chromeos/vboot2/antirollback.c @@ -35,6 +35,23 @@ } \ } while (0) + +uint32_t tpm_extend_pcr(struct vb2_context *ctx, int pcr, + enum vb2_pcr_digest which_digest) +{ + uint8_t buffer[VB2_PCR_DIGEST_RECOMMENDED_SIZE]; + uint32_t size = sizeof(buffer); + int rv; + + rv = vb2api_get_pcr_digest(ctx, which_digest, buffer, &size); + if (rv != VB2_SUCCESS) + return rv; + if (size < TPM_PCR_DIGEST) + return VB2_ERROR_UNKNOWN; + + return tlcl_extend(pcr, buffer, NULL); +} + uint32_t tpm_clear_and_reenable(void) { VBDEBUG("TPM: Clear and re-enable\n"); diff --git a/src/vendorcode/google/chromeos/vboot2/verstage.c b/src/vendorcode/google/chromeos/vboot2/verstage.c index 06d76fe24a..0ce4e89246 100644 --- a/src/vendorcode/google/chromeos/vboot2/verstage.c +++ b/src/vendorcode/google/chromeos/vboot2/verstage.c @@ -205,6 +205,12 @@ static void save_if_needed(struct vb2_context *ctx) } } +static uint32_t extend_pcrs(struct vb2_context *ctx) +{ + return tpm_extend_pcr(ctx, 0, BOOT_MODE_PCR) || + tpm_extend_pcr(ctx, 1, HWID_DIGEST_PCR); +} + /** * Verify and select the firmware in the RW image * @@ -248,6 +254,7 @@ void verstage_main(void) printk(BIOS_INFO, "Recovery requested (%x)\n", rv); /* If we need recovery mode, leave firmware selection now */ save_if_needed(&ctx); + extend_pcrs(&ctx); /* ignore failures */ timestamp_add_now(TS_END_VBOOT); return; } @@ -284,6 +291,14 @@ void verstage_main(void) vboot_reboot(); } + rv = extend_pcrs(&ctx); + if (rv) { + printk(BIOS_WARNING, "Failed to extend TPM PCRs (%#x)\n", rv); + vb2api_fail(&ctx, VB2_RECOVERY_RO_TPM_U_ERROR, rv); + save_if_needed(&ctx); + vboot_reboot(); + } + /* Lock TPM */ rv = antirollback_lock_space_firmware(); if (rv) { |