diff options
Diffstat (limited to 'src/security')
| -rw-r--r-- | src/security/vboot/antirollback.h | 1 | ||||
| -rw-r--r-- | src/security/vboot/secdata_tpm.c | 35 |
2 files changed, 36 insertions, 0 deletions
diff --git a/src/security/vboot/antirollback.h b/src/security/vboot/antirollback.h index 75bfcdc7c7..10a9e21e37 100644 --- a/src/security/vboot/antirollback.h +++ b/src/security/vboot/antirollback.h @@ -28,6 +28,7 @@ enum vb2_pcr_digest; /* 0x100d: Hash of MRC_CACHE training data for non-recovery boot */ #define MRC_RW_HASH_NV_INDEX 0x100d #define HASH_NV_SIZE VB2_SHA256_DIGEST_SIZE +#define ENT_ROLLBACK_SPACE_INDEX 0x100e /* Widevine Secure Counter space */ #define WIDEVINE_COUNTER_NV_INDEX(n) (0x3000 + (n)) #define NUM_WIDEVINE_COUNTERS 4 diff --git a/src/security/vboot/secdata_tpm.c b/src/security/vboot/secdata_tpm.c index 3ad7fc8a75..78850696c4 100644 --- a/src/security/vboot/secdata_tpm.c +++ b/src/security/vboot/secdata_tpm.c @@ -116,6 +116,17 @@ static const TPMA_NV rw_space_attributes = { .TPMA_NV_WRITE_STCLEAR = 1, }; +static const TPMA_NV rw_auth_space_attributes = { + .TPMA_NV_AUTHWRITE = 1, + .TPMA_NV_AUTHREAD = 1, + .TPMA_NV_NO_DA = 1, + .TPMA_NV_PPREAD = 1, + .TPMA_NV_PPWRITE = 1, + .TPMA_NV_PLATFORMCREATE = 1, + .TPMA_NV_WRITE_STCLEAR = 1, + .TPMA_NV_POLICY_DELETE = 1, +}; + static const TPMA_NV fwmp_attr = { .TPMA_NV_PLATFORMCREATE = 1, .TPMA_NV_OWNERWRITE = 1, @@ -342,6 +353,22 @@ static uint32_t setup_zte_spaces(void) return rv; } +/* + * Set up enterprise rollback space. + * + * This space is not used by firmware but needs to survive owner clear. Thus, it + * needs to be created here. + */ +static uint32_t enterprise_rollback_create_space(void) +{ + uint8_t rollback_space_default[32] = {0}; + + return setup_space("Enterprise Rollback Space", + ENT_ROLLBACK_SPACE_INDEX, rollback_space_default, + sizeof(rollback_space_default), rw_auth_space_attributes, + unsatisfiable_policy, sizeof(unsatisfiable_policy)); +} + static uint32_t setup_widevine_counter_spaces(void) { uint32_t index, rv; @@ -387,6 +414,14 @@ static uint32_t _factory_initialize_tpm(struct vb2_context *ctx) if (CONFIG(CHROMEOS) && !(CONFIG(TPM_GOOGLE))) RETURN_ON_FAILURE(setup_zte_spaces()); + /* + * On TPM 2.0, create a space that survives TPM clear. This allows to + * securely lock data during enterprise rollback by binding to this + * space's value. + */ + if (CONFIG(CHROMEOS)) + RETURN_ON_FAILURE(enterprise_rollback_create_space()); + /* Define widevine counter space. No need to increment/write to the secure counters and are expected to be incremented during the first use. */ if (CONFIG(VBOOT_DEFINE_WIDEVINE_COUNTERS)) |