diff options
Diffstat (limited to 'src/security/vboot/secdata_tpm.c')
| -rw-r--r-- | src/security/vboot/secdata_tpm.c | 554 |
1 files changed, 6 insertions, 548 deletions
diff --git a/src/security/vboot/secdata_tpm.c b/src/security/vboot/secdata_tpm.c index f60a5e2ee0..8714dd8fed 100644 --- a/src/security/vboot/secdata_tpm.c +++ b/src/security/vboot/secdata_tpm.c @@ -5,28 +5,12 @@ * stored in the TPM NVRAM. */ -#include <security/vboot/antirollback.h> -#include <security/vboot/tpm_common.h> +#include <console/console.h> #include <security/tpm/tspi.h> -#include <security/tpm/tss.h> -#include <security/tpm/tss/tcg-1.2/tss_structures.h> -#include <security/tpm/tss/tcg-2.0/tss_structures.h> +#include <security/vboot/antirollback.h> #include <vb2_api.h> -#include <console/console.h> -#define VBDEBUG(format, args...) \ - printk(BIOS_INFO, "%s():%d: " format, __func__, __LINE__, ## args) - -#define RETURN_ON_FAILURE(tpm_cmd) do { \ - tpm_result_t rc_; \ - if ((rc_ = (tpm_cmd)) != TPM_SUCCESS) { \ - VBDEBUG("Antirollback: %08x returned by " #tpm_cmd \ - "\n", (tpm_result_t)rc_); \ - return rc_; \ - } \ - } while (0) - -static tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length); +#include "secdata_tpm_private.h" tpm_result_t antirollback_read_space_kernel(struct vb2_context *ctx) { @@ -69,529 +53,7 @@ tpm_result_t antirollback_read_space_kernel(struct vb2_context *ctx) return TPM_SUCCESS; } -#if CONFIG(TPM2) - -static tpm_result_t read_space_mrc_hash(uint32_t index, uint8_t *data) -{ - RETURN_ON_FAILURE(tlcl_read(index, data, - HASH_NV_SIZE)); - return TPM_SUCCESS; -} - -/* - * This is used to initialize the TPM space for recovery hash after defining - * it. Since there is no data available to calculate hash at the point where TPM - * space is defined, initialize it to all 0s. - */ -static const uint8_t mrc_hash_data[HASH_NV_SIZE] = { }; - -/* - * Different sets of NVRAM space attributes apply to the "ro" spaces, - * i.e. those which should not be possible to delete or modify once - * the RO exits, and the rest of the NVRAM spaces. - */ -static const TPMA_NV ro_space_attributes = { - .TPMA_NV_PPWRITE = 1, - .TPMA_NV_AUTHREAD = 1, - .TPMA_NV_PPREAD = 1, - .TPMA_NV_PLATFORMCREATE = 1, - .TPMA_NV_WRITE_STCLEAR = 1, - .TPMA_NV_POLICY_DELETE = 1, -}; - -static const TPMA_NV rw_space_attributes = { - .TPMA_NV_PPWRITE = 1, - .TPMA_NV_AUTHREAD = 1, - .TPMA_NV_PPREAD = 1, - .TPMA_NV_PLATFORMCREATE = 1, - .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, - .TPMA_NV_AUTHREAD = 1, - .TPMA_NV_PPREAD = 1, - .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, -}; - -static const TPMA_NV rw_orderly_counter_attributes = { - .TPMA_NV_COUNTER = 1, - .TPMA_NV_ORDERLY = 1, - .TPMA_NV_AUTHREAD = 1, - .TPMA_NV_AUTHWRITE = 1, - .TPMA_NV_PLATFORMCREATE = 1, - .TPMA_NV_WRITE_STCLEAR = 1, - .TPMA_NV_PPREAD = 1, - .TPMA_NV_PPWRITE = 1, - .TPMA_NV_NO_DA = 1, -}; - -/* - * This policy digest was obtained using TPM2_PolicyOR on 3 digests - * corresponding to a sequence of - * -) TPM2_PolicyCommandCode(TPM_CC_NV_UndefineSpaceSpecial), - * -) TPM2_PolicyPCR(PCR0, <extended_value>). - * where <extended value> is - * 1) all zeros = initial, unextended state: - * - Value to extend to initial PCR0: - * <none> - * - Resulting PCR0: - * 0000000000000000000000000000000000000000000000000000000000000000 - * - Policy digest for PolicyCommandCode + PolicyPCR: - * 4B44FC4192DB5AD7167E0135708FD374890A06BFB56317DF01F24F2226542A3F - * 2) result of extending (SHA1(0x00|0x01|0x00) | 00s to SHA256 size) - * - Value to extend to initial PCR0: - * 62571891215b4efc1ceab744ce59dd0b66ea6f73000000000000000000000000 - * - Resulting PCR0: - * 9F9EA866D3F34FE3A3112AE9CB1FBABC6FFE8CD261D42493BC6842A9E4F93B3D - * - Policy digest for PolicyCommandCode + PolicyPCR: - * CB5C8014E27A5F7586AAE42DB4F9776A977BCBC952CA61E33609DA2B2C329418 - * 3) result of extending (SHA1(0x01|0x01|0x00) | 00s to SHA256 size) - * - Value to extend to initial PCR0: - * 47ec8d98366433dc002e7721c9e37d5067547937000000000000000000000000 - * - Resulting PCR0: - * 2A7580E5DA289546F4D2E0509CC6DE155EA131818954D36D49E027FD42B8C8F8 - * - Policy digest for PolicyCommandCode + PolicyPCR: - * E6EF4F0296AC3EF0F53906480985B1BE8058E0E517E5F74A5B8A415EFE339D87 - * Values #2 and #3 correspond to two forms of recovery mode as extended by - * vb2api_get_pcr_digest(). - * As a result, the digest allows deleting the space with UndefineSpaceSpecial - * at early RO stages (before extending PCR0) or from recovery mode. - */ -static const uint8_t pcr0_allowed_policy[] = { - 0x44, 0x44, 0x79, 0x00, 0xCB, 0xB8, 0x3F, 0x5B, 0x15, 0x76, 0x56, - 0x50, 0xEF, 0x96, 0x98, 0x0A, 0x2B, 0x96, 0x6E, 0xA9, 0x09, 0x04, - 0x4A, 0x01, 0xB8, 0x5F, 0xA5, 0x4A, 0x96, 0xFC, 0x59, 0x84}; - -static const uint8_t unsatisfiable_policy[VB2_SHA256_DIGEST_SIZE] = - "hmwhat if RBR beat merc in 2021"; - -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) -{ - tpm_result_t rc; - - rc = tlcl2_define_space(index, length, nv_attributes, nv_policy, nv_policy_size); - if (rc == TPM_CB_NV_DEFINED) { - /* - * Continue with writing: it may be defined, but not written - * to. In that case a subsequent tlcl_read() would still return - * TPM_BADINDEX on TPM 2.0. The cases when some non-firmware - * space is defined while the firmware space is not there - * should be rare (interrupted initialization), so no big harm - * in writing once again even if it was written already. - */ - VBDEBUG("%s: %s space already exists\n", __func__, name); - rc = TPM_SUCCESS; - } - - return rc; -} - -static tpm_result_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) -{ - tpm_result_t rc; - - rc = define_space(name, index, length, nv_attributes, nv_policy, - nv_policy_size); - if (rc != TPM_SUCCESS) - return rc; - - return safe_write(index, data, length); -} - -static tpm_result_t setup_firmware_space(struct vb2_context *ctx) -{ - uint32_t firmware_space_size = vb2api_secdata_firmware_create(ctx); - - return setup_space("firmware", FIRMWARE_NV_INDEX, - ctx->secdata_firmware, firmware_space_size, - ro_space_attributes, pcr0_allowed_policy, - sizeof(pcr0_allowed_policy)); -} - -static tpm_result_t setup_fwmp_space(struct vb2_context *ctx) -{ - uint32_t fwmp_space_size = vb2api_secdata_fwmp_create(ctx); - - return setup_space("FWMP", FWMP_NV_INDEX, ctx->secdata_fwmp, fwmp_space_size, - fwmp_attr, NULL, 0); -} - -static tpm_result_t setup_kernel_space(struct vb2_context *ctx) -{ - uint32_t kernel_space_size = vb2api_secdata_kernel_create(ctx); - - return setup_space("kernel", KERNEL_NV_INDEX, ctx->secdata_kernel, - kernel_space_size, rw_space_attributes, NULL, 0); -} - -static tpm_result_t set_mrc_hash_space(uint32_t index, const uint8_t *data) -{ - if (index == MRC_REC_HASH_NV_INDEX) { - return setup_space("RO MRC Hash", index, data, HASH_NV_SIZE, - ro_space_attributes, pcr0_allowed_policy, - sizeof(pcr0_allowed_policy)); - } else { - return setup_space("RW MRC Hash", index, data, HASH_NV_SIZE, - rw_space_attributes, NULL, 0); - } -} - -/** - * Set up the Zero-Touch Enrollment(ZTE) related spaces. - * - * These spaces are not used by firmware, but we do need to initialize them. - */ -static tpm_result_t setup_zte_spaces(void) -{ - tpm_result_t rc; - 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 */ - rc = 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 (rc != TPM_SUCCESS) { - VBDEBUG("%s: Failed to set up RMA + SN Bits space with error %#x\n", __func__, rc); - return rc; - } - - rc = setup_space("Board ID", ZTE_BOARD_ID_NV_INDEX, - board_id_default, sizeof(board_id_default), - zte_attr, - unsatisfiable_policy, sizeof(unsatisfiable_policy)); - if (rc != TPM_SUCCESS) { - VBDEBUG("%s: Failed to set up Board ID space with error %#x\n", __func__, rc); - return rc; - } - - /* Set up RMA Bytes counter */ - rc = 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 (rc != TPM_SUCCESS) { - VBDEBUG("%s: Failed to define RMA Bytes space with error %#x\n", __func__, rc); - return rc; - } - - /* - * Since the RMA counter has the BITS attribute, we need to call - * TPM2_NV_SetBits() in order to initialize it. - */ - rc = tlcl2_set_bits(ZTE_RMA_BYTES_COUNTER_INDEX, rma_bytes_counter_default); - if (rc != TPM_SUCCESS) { - VBDEBUG("%s: Failed to init RMA Bytes counter space wit error %#x\n", - __func__, rc); - return rc; - } - - return rc; -} - -/* - * 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 tpm_result_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 tpm_result_t setup_widevine_counter_spaces(void) -{ - uint32_t index; - tpm_result_t rc; - - for (index = 0; index < NUM_WIDEVINE_COUNTERS; index++) { - rc = define_space(WIDEVINE_COUNTER_NAME, - WIDEVINE_COUNTER_NV_INDEX(index), - WIDEVINE_COUNTER_SIZE, - rw_orderly_counter_attributes, - NULL, - 0); - if (rc != TPM_SUCCESS) - return rc; - } - return rc; -} - -static tpm_result_t _factory_initialize_tpm2(struct vb2_context *ctx) -{ - RETURN_ON_FAILURE(tlcl_force_clear()); - - /* - * Of all NVRAM spaces defined by this function the firmware space - * must be defined last, because its existence is considered an - * indication that TPM factory initialization was successfully - * completed. - */ - RETURN_ON_FAILURE(setup_kernel_space(ctx)); - - /* - * Define and set rec hash space, if available. No need to - * create the RW hash space because we will definitely boot - * once in normal mode before shipping, meaning that the space - * will get created with correct permissions while still in - * our hands. - */ - if (CONFIG(VBOOT_HAS_REC_HASH_SPACE)) - RETURN_ON_FAILURE(set_mrc_hash_space(MRC_REC_HASH_NV_INDEX, mrc_hash_data)); - - /* Define and write firmware management parameters space. */ - RETURN_ON_FAILURE(setup_fwmp_space(ctx)); - - /* - * Define and write zero-touch enrollment (ZTE) spaces. For ChromeOS devices with - * Google TPM, these are set up elsewhere via TPM vendor commands. - */ - 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)) - RETURN_ON_FAILURE(setup_widevine_counter_spaces()); - - RETURN_ON_FAILURE(setup_firmware_space(ctx)); - - return TPM_SUCCESS; -} - -tpm_result_t antirollback_read_space_mrc_hash(uint32_t index, uint8_t *data, uint32_t size) -{ - if (size != HASH_NV_SIZE) { - VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. " - "(Expected=%#x Actual=%#x).\n", index, HASH_NV_SIZE, - size); - return TPM_CB_READ_FAILURE; - } - return read_space_mrc_hash(index, data); -} - -tpm_result_t antirollback_write_space_mrc_hash(uint32_t index, const uint8_t *data, uint32_t size) -{ - uint8_t spc_data[HASH_NV_SIZE]; - tpm_result_t rc; - - if (size != HASH_NV_SIZE) { - VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. " - "(Expected=%#x Actual=%#x).\n", index, HASH_NV_SIZE, - size); - return TPM_CB_WRITE_FAILURE; - } - - rc = read_space_mrc_hash(index, spc_data); - if (rc == TPM_BADINDEX) { - /* - * If space is not defined already for hash, define - * new space. - */ - VBDEBUG("TPM: Initializing hash space.\n"); - return set_mrc_hash_space(index, data); - } - - if (rc != TPM_SUCCESS) - return rc; - - return safe_write(index, data, size); -} - -tpm_result_t antirollback_lock_space_mrc_hash(uint32_t index) -{ - return tlcl2_lock_nv_write(index); -} - -static tpm_result_t read_space_vbios_hash(uint8_t *data) -{ - RETURN_ON_FAILURE(tlcl_read(VBIOS_CACHE_NV_INDEX, data, HASH_NV_SIZE)); - return TPM_SUCCESS; -} - -tpm_result_t antirollback_read_space_vbios_hash(uint8_t *data, uint32_t size) -{ - if (size != HASH_NV_SIZE) { - VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. " - "(Expected=%#x Actual=%#x).\n", VBIOS_CACHE_NV_INDEX, HASH_NV_SIZE, - size); - return TPM_CB_READ_FAILURE; - } - return read_space_vbios_hash(data); -} - -tpm_result_t antirollback_write_space_vbios_hash(const uint8_t *data, uint32_t size) -{ - uint8_t spc_data[HASH_NV_SIZE]; - tpm_result_t rc; - - if (size != HASH_NV_SIZE) { - VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. " - "(Expected=%#x Actual=%#x).\n", VBIOS_CACHE_NV_INDEX, HASH_NV_SIZE, - size); - return TPM_CB_WRITE_FAILURE; - } - - rc = read_space_vbios_hash(spc_data); - if (rc == TPM_BADINDEX) { - /* - * If space is not defined already for hash, define - * new space. - */ - VBDEBUG("TPM: Initializing hash space.\n"); - return setup_space("VBIOS Cache Hash", VBIOS_CACHE_NV_INDEX, data, HASH_NV_SIZE, - rw_space_attributes, NULL, 0); - } - - if (rc != TPM_SUCCESS) - return rc; - - return safe_write(VBIOS_CACHE_NV_INDEX, data, size); -} - -#endif /* CONFIG(TPM2) */ - -#if CONFIG(TPM1) - -/** - * Similarly to safe_write(), this ensures we don't fail a DefineSpace because - * we hit the TPM write limit. This is even less likely to happen than with - * writes because we only define spaces once at initialization, but we'd - * rather be paranoid about this. - */ -static tpm_result_t safe_define_space(uint32_t index, uint32_t perm, uint32_t size) -{ - tpm_result_t rc = tlcl1_define_space(index, perm, size); - if (rc == TPM_MAXNVWRITES) { - RETURN_ON_FAILURE(tpm_clear_and_reenable()); - return tlcl1_define_space(index, perm, size); - } else { - return rc; - } -} - -static tpm_result_t _factory_initialize_tpm1(struct vb2_context *ctx) -{ - TPM_PERMANENT_FLAGS pflags; - tpm_result_t rc; - - vb2api_secdata_firmware_create(ctx); - vb2api_secdata_kernel_create_v0(ctx); - - rc = tlcl1_get_permanent_flags(&pflags); - if (rc != TPM_SUCCESS) - return rc; - - /* - * TPM may come from the factory without physical presence finalized. - * Fix if necessary. - */ - VBDEBUG("TPM: physicalPresenceLifetimeLock=%d\n", - pflags.physicalPresenceLifetimeLock); - if (!pflags.physicalPresenceLifetimeLock) { - VBDEBUG("TPM: Finalizing physical presence\n"); - RETURN_ON_FAILURE(tlcl_finalize_physical_presence()); - } - - /* - * The TPM will not enforce the NV authorization restrictions until the - * execution of a TPM_NV_DefineSpace with the handle of - * TPM_NV_INDEX_LOCK. Here we create that space if it doesn't already - * exist. */ - VBDEBUG("TPM: nvLocked=%d\n", pflags.nvLocked); - if (!pflags.nvLocked) { - VBDEBUG("TPM: Enabling NV locking\n"); - RETURN_ON_FAILURE(tlcl1_set_nv_locked()); - } - - /* Clear TPM owner, in case the TPM is already owned for some reason. */ - VBDEBUG("TPM: Clearing owner\n"); - RETURN_ON_FAILURE(tpm_clear_and_reenable()); - - /* Define and write secdata_kernel space. */ - RETURN_ON_FAILURE(safe_define_space(KERNEL_NV_INDEX, - TPM_NV_PER_PPWRITE, - VB2_SECDATA_KERNEL_SIZE_V02)); - RETURN_ON_FAILURE(safe_write(KERNEL_NV_INDEX, - ctx->secdata_kernel, - VB2_SECDATA_KERNEL_SIZE_V02)); - - /* Define and write secdata_firmware space. */ - RETURN_ON_FAILURE(safe_define_space(FIRMWARE_NV_INDEX, - TPM_NV_PER_GLOBALLOCK | - TPM_NV_PER_PPWRITE, - VB2_SECDATA_FIRMWARE_SIZE)); - RETURN_ON_FAILURE(safe_write(FIRMWARE_NV_INDEX, - ctx->secdata_firmware, - VB2_SECDATA_FIRMWARE_SIZE)); - - return TPM_SUCCESS; -} - -#endif /* CONFIG(TPM1) */ - -static tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length) +tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length) { tpm_result_t rc = tlcl_write(index, data, length); if (tlcl_get_family() == TPM_1 && rc == TPM_MAXNVWRITES) { @@ -609,14 +71,10 @@ static tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length static uint32_t _factory_initialize_tpm(struct vb2_context *ctx) { -#if CONFIG(TPM1) if (tlcl_get_family() == TPM_1) - return _factory_initialize_tpm1(ctx); -#endif -#if CONFIG(TPM2) + return factory_initialize_tpm1(ctx); if (tlcl_get_family() == TPM_2) - return _factory_initialize_tpm2(ctx); -#endif + return factory_initialize_tpm2(ctx); return TPM_CB_CORRUPTED_STATE; } |