diff options
Diffstat (limited to 'src/drivers/intel')
| -rw-r--r-- | src/drivers/intel/fsp2_0/Kconfig | 6 | ||||
| -rw-r--r-- | src/drivers/intel/fsp2_0/memory_init.c | 121 |
2 files changed, 127 insertions, 0 deletions
diff --git a/src/drivers/intel/fsp2_0/Kconfig b/src/drivers/intel/fsp2_0/Kconfig index c653148696..4f40c3fa25 100644 --- a/src/drivers/intel/fsp2_0/Kconfig +++ b/src/drivers/intel/fsp2_0/Kconfig @@ -94,4 +94,10 @@ config RESET_ON_INVALID_RAMSTAGE_CACHE bool "Reset the system on S3 wake when ramstage cache invalid." default n +config FSP2_0_USES_TPM_MRC_HASH + bool + default y if HAS_RECOVERY_MRC_CACHE + default n + select VBOOT_HAS_REC_HASH_SPACE + endif diff --git a/src/drivers/intel/fsp2_0/memory_init.c b/src/drivers/intel/fsp2_0/memory_init.c index 3ea1897646..30da906819 100644 --- a/src/drivers/intel/fsp2_0/memory_init.c +++ b/src/drivers/intel/fsp2_0/memory_init.c @@ -11,6 +11,8 @@ * (at your option) any later version. */ +#include <antirollback.h> +#include <arch/early_variables.h> #include <arch/io.h> #include <arch/cpu.h> #include <arch/symbols.h> @@ -28,7 +30,79 @@ #include <string.h> #include <symbols.h> #include <timestamp.h> +#include <tpm_lite/tlcl.h> #include <vboot/vboot_common.h> +#include <vb2_api.h> + +static uint8_t tpm_init_done CAR_GLOBAL; + +static int mrc_cache_tpm_init(void) +{ + uint8_t done = car_get_var(tpm_init_done); + + if (done) + return 0; + + if (tlcl_lib_init() != VB2_SUCCESS) + return -1; + + car_set_var(tpm_init_done, 1); + return 0; +} + +static void mrc_cache_update_tpm_hash(const uint8_t *data, size_t size) +{ + uint8_t data_hash[VB2_SHA256_DIGEST_SIZE]; + static const uint8_t dead_hash[VB2_SHA256_DIGEST_SIZE] = { + 0xba, 0xad, 0xda, 0x1a, /* BAADDA1A */ + 0xde, 0xad, 0xde, 0xad, /* DEADDEAD */ + 0xde, 0xad, 0xda, 0x1a, /* DEADDA1A */ + 0xba, 0xad, 0xba, 0xad, /* BAADBAAD */ + 0xba, 0xad, 0xda, 0x1a, /* BAADDA1A */ + 0xde, 0xad, 0xde, 0xad, /* DEADDEAD */ + 0xde, 0xad, 0xda, 0x1a, /* DEADDA1A */ + 0xba, 0xad, 0xba, 0xad, /* BAADBAAD */ + }; + const uint8_t *hash_ptr = data_hash; + + /* We do not store normal mode data hash in TPM. */ + if (!vboot_recovery_mode_enabled()) + return; + + /* Bail out early if no mrc hash space is supported in TPM. */ + if (!IS_ENABLED(CONFIG_FSP2_0_USES_TPM_MRC_HASH)) + return; + + /* Initialize TPM driver. */ + if (mrc_cache_tpm_init()) { + printk(BIOS_ERR, "MRC: TPM driver initialization failed.\n"); + return; + } + + /* Calculate hash of data generated by MRC. */ + if (vb2_digest_buffer(data, size, VB2_HASH_SHA256, data_hash, + sizeof(data_hash))) { + printk(BIOS_ERR, "MRC: SHA-256 calculation failed for data. " + "Not updating TPM hash space.\n"); + /* + * Since data is being updated in recovery cache, the hash + * currently stored in TPM recovery hash space is no longer + * valid. If we are not able to calculate hash of the data being + * updated, reset all the bits in TPM recovery hash space to + * pre-defined hash pattern. + */ + hash_ptr = dead_hash; + } + + /* Write hash of data to TPM space. */ + if (antirollback_write_space_rec_hash(hash_ptr, VB2_SHA256_DIGEST_SIZE) + != TPM_SUCCESS) { + printk(BIOS_ERR, "MRC: Could not save hash to TPM.\n"); + return; + } + + printk(BIOS_INFO, "MRC: TPM MRC hash updated successfully.\n"); +} static void save_memory_training_data(bool s3wake, uint32_t fsp_version) { @@ -53,6 +127,8 @@ static void save_memory_training_data(bool s3wake, uint32_t fsp_version) if (mrc_cache_stash_data_with_version(mrc_data, mrc_data_size, fsp_version) < 0) printk(BIOS_ERR, "Failed to stash MRC data\n"); + + mrc_cache_update_tpm_hash(mrc_data, mrc_data_size); } static void do_fsp_post_memory_init(bool s3wake, uint32_t fsp_version) @@ -110,6 +186,48 @@ static const char *mrc_cache_get_region_name(void) return RECOVERY_MRC_CACHE; } +static int mrc_cache_verify_tpm_hash(const uint8_t *data, size_t size) +{ + uint8_t data_hash[VB2_SHA256_DIGEST_SIZE]; + uint8_t tpm_hash[VB2_SHA256_DIGEST_SIZE]; + + /* We do not store normal mode data hash in TPM. */ + if (!vboot_recovery_mode_enabled()) + return 1; + + if (!IS_ENABLED(CONFIG_FSP2_0_USES_TPM_MRC_HASH)) + return 1; + + /* Calculate hash of data read from RECOVERY_MRC_CACHE. */ + if (vb2_digest_buffer(data, size, VB2_HASH_SHA256, data_hash, + sizeof(data_hash))) { + printk(BIOS_ERR, "MRC: SHA-256 calculation failed for data.\n"); + return 0; + } + + /* Initialize TPM driver. */ + if (mrc_cache_tpm_init()) { + printk(BIOS_ERR, "MRC: TPM driver initialization failed.\n"); + return 0; + } + + /* Read hash of MRC data saved in TPM. */ + if (antirollback_read_space_rec_hash(tpm_hash, sizeof(tpm_hash)) + != TPM_SUCCESS) { + printk(BIOS_ERR, "MRC: Could not read hash from TPM.\n"); + return 0; + } + + if (memcmp(tpm_hash, data_hash, sizeof(tpm_hash))) { + printk(BIOS_ERR, "MRC: Hash comparison failed.\n"); + return 0; + } + + printk(BIOS_INFO, "MRC: Hash comparison successful. " + "Using data from RECOVERY_MRC_CACHE\n"); + return 1; +} + static void fsp_fill_mrc_cache(FSPM_ARCH_UPD *arch_upd, bool s3wake, uint32_t fsp_version) { @@ -126,6 +244,9 @@ static void fsp_fill_mrc_cache(FSPM_ARCH_UPD *arch_upd, bool s3wake, if (mrc_cache_get_current_from_region(&mrc_cache, fsp_version, name)) return; + if (!mrc_cache_verify_tpm_hash(mrc_cache->data, mrc_cache->size)) + return; + /* MRC cache found */ arch_upd->NvsBufferPtr = (void *)mrc_cache->data; arch_upd->BootMode = s3wake ? |