From 80961af4b6888ff31aacaae0753969db4a8fb734 Mon Sep 17 00:00:00 2001 From: Philipp Deppenwiese Date: Tue, 27 Feb 2018 22:14:34 +0100 Subject: security/vboot: Add interface for FSP 2.0 mrc caching * Move vboot/tpm specific implementation to vboot. * Only call functions if CONFIG_FSP2_0_USES_TPM_MRC_HASH is set. * Preparation for software hash function support, no logic changed. Change-Id: I41a458186c7981adaf3fea8974adec2ca8668f14 Signed-off-by: Philipp Deppenwiese Reviewed-on: https://review.coreboot.org/24904 Reviewed-by: Aaron Durbin Reviewed-by: Philipp Deppenwiese Tested-by: build bot (Jenkins) --- src/drivers/intel/fsp2_0/include/fsp/memory_init.h | 32 +++++++ src/drivers/intel/fsp2_0/memory_init.c | 105 ++------------------- 2 files changed, 38 insertions(+), 99 deletions(-) create mode 100644 src/drivers/intel/fsp2_0/include/fsp/memory_init.h (limited to 'src/drivers/intel') diff --git a/src/drivers/intel/fsp2_0/include/fsp/memory_init.h b/src/drivers/intel/fsp2_0/include/fsp/memory_init.h new file mode 100644 index 0000000000..05ea440275 --- /dev/null +++ b/src/drivers/intel/fsp2_0/include/fsp/memory_init.h @@ -0,0 +1,32 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2018 Facebook Inc + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _FSP2_0_MEMORY_INIT_H_ +#define _FSP2_0_MEMORY_INIT_H_ + +#include + +/* + * Updates mrc cache hash if it differs. + */ +void mrc_cache_update_hash(const uint8_t *data, size_t size); + +/* + * Verifies mrc cache hash which is stored somewhere. + * return 1 verification was successful and 0 for error. + */ +int mrc_cache_verify_hash(const uint8_t *data, size_t size); + +#endif /* _FSP2_0_MEMORY_INIT_H_ */ diff --git a/src/drivers/intel/fsp2_0/memory_init.c b/src/drivers/intel/fsp2_0/memory_init.c index 1ca52085a7..cf033d7077 100644 --- a/src/drivers/intel/fsp2_0/memory_init.c +++ b/src/drivers/intel/fsp2_0/memory_init.c @@ -31,63 +31,10 @@ #include #include #include -#include #include +#include #include - -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 (tlcl_lib_init() != VB2_SUCCESS) { - 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"); -} +#include static void save_memory_training_data(bool s3wake, uint32_t fsp_version) { @@ -113,7 +60,8 @@ static void save_memory_training_data(bool s3wake, uint32_t fsp_version) mrc_data_size) < 0) printk(BIOS_ERR, "Failed to stash MRC data\n"); - mrc_cache_update_tpm_hash(mrc_data, mrc_data_size); + if (IS_ENABLED(CONFIG_FSP2_0_USES_TPM_MRC_HASH)) + mrc_cache_update_hash(mrc_data, mrc_data_size); } static void do_fsp_post_memory_init(bool s3wake, uint32_t fsp_version) @@ -156,48 +104,6 @@ static void do_fsp_post_memory_init(bool s3wake, uint32_t fsp_version) tpm_setup(s3wake); } -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 (tlcl_lib_init() != VB2_SUCCESS) { - 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, uint32_t fsp_version) { struct region_device rdev; @@ -230,7 +136,8 @@ static void fsp_fill_mrc_cache(FSPM_ARCH_UPD *arch_upd, uint32_t fsp_version) if (data == NULL) return; - if (!mrc_cache_verify_tpm_hash(data, region_device_sz(&rdev))) + if (IS_ENABLED(CONFIG_FSP2_0_USES_TPM_MRC_HASH) && + !mrc_cache_verify_hash(data, region_device_sz(&rdev))) return; /* MRC cache found */ -- cgit v1.2.3