diff options
Diffstat (limited to 'src/security/vboot')
-rw-r--r-- | src/security/vboot/antirollback.h | 4 | ||||
-rw-r--r-- | src/security/vboot/secdata_tpm.c | 122 |
2 files changed, 118 insertions, 8 deletions
diff --git a/src/security/vboot/antirollback.h b/src/security/vboot/antirollback.h index fcfa7a270c..a208c04610 100644 --- a/src/security/vboot/antirollback.h +++ b/src/security/vboot/antirollback.h @@ -28,6 +28,10 @@ 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 +/* Zero-Touch Enrollment related spaces */ +#define ZTE_BOARD_ID_NV_INDEX 0x3fff00 +#define ZTE_RMA_SN_BITS_INDEX 0x3fff01 +#define ZTE_RMA_BYTES_COUNTER_INDEX 0x3fff04 /* Structure definitions for TPM spaces */ diff --git a/src/security/vboot/secdata_tpm.c b/src/security/vboot/secdata_tpm.c index dd367964cc..bedead7a81 100644 --- a/src/security/vboot/secdata_tpm.c +++ b/src/security/vboot/secdata_tpm.c @@ -117,6 +117,29 @@ static const TPMA_NV fwmp_attr = { .TPMA_NV_PPWRITE = 1, }; +/* Attributes for spaces that enable zero-touch enrollment (ZTE) */ +static const TPMA_NV zte_attr = { + .TPMA_NV_PLATFORMCREATE = 1, + .TPMA_NV_WRITEDEFINE = 1, + .TPMA_NV_AUTHWRITE = 1, + .TPMA_NV_AUTHREAD = 1, + .TPMA_NV_PPWRITE = 1, + .TPMA_NV_PPREAD = 1, + .TPMA_NV_NO_DA = 1, + .TPMA_NV_POLICY_DELETE = 1, +}; + +static const TPMA_NV zte_rma_bytes_attr = { + .TPMA_NV_PLATFORMCREATE = 1, + .TPMA_NV_BITS = 1, + .TPMA_NV_AUTHWRITE = 1, + .TPMA_NV_AUTHREAD = 1, + .TPMA_NV_PPWRITE = 1, + .TPMA_NV_PPREAD = 1, + .TPMA_NV_NO_DA = 1, + .TPMA_NV_POLICY_DELETE = 1, +}; + /* * This policy digest was obtained using TPM2_PolicyOR on 3 digests * corresponding to a sequence of @@ -154,15 +177,12 @@ static const uint8_t pcr0_allowed_policy[] = { 0x50, 0xEF, 0x96, 0x98, 0x0A, 0x2B, 0x96, 0x6E, 0xA9, 0x09, 0x04, 0x4A, 0x01, 0xB8, 0x5F, 0xA5, 0x4A, 0x96, 0xFC, 0x59, 0x84}; -/* Nothing special in the TPM2 path yet. */ -static uint32_t safe_write(uint32_t index, const void *data, uint32_t length) -{ - return tlcl_write(index, data, length); -} +static const uint8_t unsatisfiable_policy[VB2_SHA256_DIGEST_SIZE] = + "hmwhat if RBR beat merc in 2021"; -static uint32_t setup_space(const char *name, uint32_t index, const void *data, - uint32_t length, const TPMA_NV nv_attributes, - const uint8_t *nv_policy, size_t nv_policy_size) +static uint32_t define_space(const char *name, uint32_t index, uint32_t length, + const TPMA_NV nv_attributes, + const uint8_t *nv_policy, size_t nv_policy_size) { uint32_t rv; @@ -181,6 +201,23 @@ static uint32_t setup_space(const char *name, uint32_t index, const void *data, rv = TPM_SUCCESS; } + return rv; +} + +/* Nothing special in the TPM2 path yet. */ +static uint32_t safe_write(uint32_t index, const void *data, uint32_t length) +{ + return tlcl_write(index, data, length); +} + +static uint32_t setup_space(const char *name, uint32_t index, const void *data, + uint32_t length, const TPMA_NV nv_attributes, + const uint8_t *nv_policy, size_t nv_policy_size) +{ + uint32_t rv; + + rv = define_space(name, index, length, nv_attributes, nv_policy, + nv_policy_size); if (rv != TPM_SUCCESS) return rv; @@ -225,6 +262,67 @@ static uint32_t set_mrc_hash_space(uint32_t index, const uint8_t *data) } } +/** + * Set up the Zero-Touch Enrollment(ZTE) related spaces. + * + * These spaces are not used by firmware, but we do need to initialize them. + */ +static uint32_t setup_zte_spaces(void) +{ + uint32_t rv; + uint64_t rma_bytes_counter_default = 0; + uint8_t rma_sn_bits_default[16]; + uint8_t board_id_default[12]; + + /* Initialize defaults: Board ID and RMA+SN Bits must be initialized + to all 0xFFs. */ + memset(rma_sn_bits_default, 0xFF, ARRAY_SIZE(rma_sn_bits_default)); + memset(board_id_default, 0xFF, ARRAY_SIZE(board_id_default)); + + /* Set up RMA + SN Bits */ + rv = setup_space("RMA + SN Bits", ZTE_RMA_SN_BITS_INDEX, + rma_sn_bits_default, sizeof(rma_sn_bits_default), + zte_attr, + unsatisfiable_policy, sizeof(unsatisfiable_policy)); + if (rv != TPM_SUCCESS) { + VBDEBUG("%s: Failed to set up RMA + SN Bits space\n", __func__); + return rv; + } + + rv = setup_space("Board ID", ZTE_BOARD_ID_NV_INDEX, + board_id_default, sizeof(board_id_default), + zte_attr, + unsatisfiable_policy, sizeof(unsatisfiable_policy)); + if (rv != TPM_SUCCESS) { + VBDEBUG("%s: Failed to set up Board ID space\n", __func__); + return rv; + } + + /* Set up RMA Bytes counter */ + rv = define_space("RMA Bytes Counter", ZTE_RMA_BYTES_COUNTER_INDEX, + sizeof(rma_bytes_counter_default), + zte_rma_bytes_attr, + unsatisfiable_policy, sizeof(unsatisfiable_policy)); + if (rv != TPM_SUCCESS) { + VBDEBUG("%s: Failed to define RMA Bytes space\n", __func__); + return rv; + } + + /* + * Since the RMA counter has the BITS attribute, we need to call + * TPM2_NV_SetBits() in order to initialize it. + */ + rv = tlcl_set_bits(ZTE_RMA_BYTES_COUNTER_INDEX, + rma_bytes_counter_default); + if (rv != TPM_SUCCESS) { + VBDEBUG("%s: Failed to init RMA Bytes counter space\n", + __func__); + return rv; + } + + return rv; +} + static uint32_t _factory_initialize_tpm(struct vb2_context *ctx) { RETURN_ON_FAILURE(tlcl_force_clear()); @@ -250,6 +348,14 @@ static uint32_t _factory_initialize_tpm(struct vb2_context *ctx) /* Define and write firmware management parameters space. */ RETURN_ON_FAILURE(setup_fwmp_space(ctx)); + /* + * Define and write zero-touch enrollment (ZTE) spaces. For Cr50 devices, + * these are set up elsewhere via TPM vendor commands. + */ + if (CONFIG(CHROMEOS) && (!(CONFIG(MAINBOARD_HAS_SPI_TPM_CR50) || + CONFIG(MAINBOARD_HAS_I2C_TPM_CR50)))) + RETURN_ON_FAILURE(setup_zte_spaces()); + RETURN_ON_FAILURE(setup_firmware_space(ctx)); return TPM_SUCCESS; |