From 346cee3ac5782fefeaeda2b54914b029547adf52 Mon Sep 17 00:00:00 2001 From: Ruchika Gupta Date: Tue, 14 Sep 2021 12:14:31 +0530 Subject: [PATCH] efi_loader: Fix spec ID event creation TCG EFI Protocol Specification defines the number_of_algorithms field in spec ID event to be equal to the number of active algorithms supported by the TPM device. In current implementation, this field is populated with the count of all algorithms supported by the TPM which leads to incorrect spec ID event creation. Similarly, the algorithm array in spec ID event should be a variable length array with length being equal to the number_of_algorithms field. In current implementation this is defined as a fixed length array which has been fixed. Signed-off-by: Ruchika Gupta CC: Masahisa Kojima CC: Ilias Apalodimas CC: Heinrich Schuchardt Reviewed-by: Ilias Apalodimas --- include/efi_tcg2.h | 7 +------ lib/efi_loader/efi_tcg2.c | 40 ++++++++++++++++++++++----------------- 2 files changed, 24 insertions(+), 23 deletions(-) diff --git a/include/efi_tcg2.h b/include/efi_tcg2.h index 5a1a36212e..8f02d4fb0b 100644 --- a/include/efi_tcg2.h +++ b/include/efi_tcg2.h @@ -165,8 +165,6 @@ struct tcg_efi_spec_id_event_algorithm_size { * @digest_sizes: array of number_of_algorithms pairs * 1st member defines the algorithm id * 2nd member defines the algorithm size - * @vendor_info_size: size in bytes for vendor specific info - * @vendor_info: vendor specific info */ struct tcg_efi_spec_id_event { u8 signature[16]; @@ -176,10 +174,7 @@ struct tcg_efi_spec_id_event { u8 spec_errata; u8 uintn_size; u32 number_of_algorithms; - struct tcg_efi_spec_id_event_algorithm_size digest_sizes[TPM2_NUM_PCR_BANKS]; - u8 vendor_info_size; - /* U-Boot does not provide any vendor info */ - u8 vendor_info[]; + struct tcg_efi_spec_id_event_algorithm_size digest_sizes[]; } __packed; /** diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c index cb48919223..d3b8f93f14 100644 --- a/lib/efi_loader/efi_tcg2.c +++ b/lib/efi_loader/efi_tcg2.c @@ -575,9 +575,10 @@ static efi_status_t tcg2_create_digest(const u8 *input, u32 length, EFI_PRINT("Unsupported algorithm %x\n", hash_alg); return EFI_INVALID_PARAMETER; } + digest_list->digests[digest_list->count].hash_alg = hash_alg; + memcpy(&digest_list->digests[digest_list->count].digest, final, + (u32)alg_to_len(hash_alg)); digest_list->count++; - digest_list->digests[i].hash_alg = hash_alg; - memcpy(&digest_list->digests[i].digest, final, (u32)alg_to_len(hash_alg)); } return EFI_SUCCESS; @@ -798,8 +799,9 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size, EFI_PRINT("Unsupported algorithm %x\n", hash_alg); return EFI_INVALID_PARAMETER; } - digest_list->digests[i].hash_alg = hash_alg; - memcpy(&digest_list->digests[i].digest, hash, (u32)alg_to_len(hash_alg)); + digest_list->digests[digest_list->count].hash_alg = hash_alg; + memcpy(&digest_list->digests[digest_list->count].digest, hash, + (u32)alg_to_len(hash_alg)); digest_list->count++; } @@ -1120,7 +1122,7 @@ static efi_status_t create_specid_event(struct udevice *dev, void *buffer, struct tcg_efi_spec_id_event *spec_event; size_t spec_event_size; efi_status_t ret = EFI_DEVICE_ERROR; - u32 active = 0, supported = 0; + u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0; int err; size_t i; @@ -1142,25 +1144,29 @@ static efi_status_t create_specid_event(struct udevice *dev, void *buffer, TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2; spec_event->uintn_size = sizeof(efi_uintn_t) / sizeof(u32); - err = tpm2_get_pcr_info(dev, &supported, &active, - &spec_event->number_of_algorithms); + err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count); + if (err) goto out; - if (spec_event->number_of_algorithms > MAX_HASH_COUNT || - spec_event->number_of_algorithms < 1) - goto out; - for (i = 0; i < spec_event->number_of_algorithms; i++) { + for (i = 0; i < pcr_count; i++) { u16 hash_alg = hash_algo_list[i].hash_alg; u16 hash_len = hash_algo_list[i].hash_len; - if (active && alg_to_mask(hash_alg)) { + if (active & alg_to_mask(hash_alg)) { put_unaligned_le16(hash_alg, - &spec_event->digest_sizes[i].algorithm_id); + &spec_event->digest_sizes[alg_count].algorithm_id); put_unaligned_le16(hash_len, - &spec_event->digest_sizes[i].digest_size); + &spec_event->digest_sizes[alg_count].digest_size); + alg_count++; } } + + spec_event->number_of_algorithms = alg_count; + if (spec_event->number_of_algorithms > MAX_HASH_COUNT || + spec_event->number_of_algorithms < 1) + goto out; + /* * the size of the spec event and placement of vendor_info_size * depends on supported algoriths @@ -1169,9 +1175,9 @@ static efi_status_t create_specid_event(struct udevice *dev, void *buffer, offsetof(struct tcg_efi_spec_id_event, digest_sizes) + spec_event->number_of_algorithms * sizeof(spec_event->digest_sizes[0]); /* no vendor info for us */ - memset(buffer + spec_event_size, 0, - sizeof(spec_event->vendor_info_size)); - spec_event_size += sizeof(spec_event->vendor_info_size); + memset(buffer + spec_event_size, 0, 1); + /* add a byte for vendor_info_size in the spec event */ + spec_event_size += 1; *event_size = spec_event_size; return EFI_SUCCESS; -- 2.39.5