From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masahisa Kojima Date: Thu, 15 Apr 2021 22:30:20 +0900 Subject: [PATCH 2/2] efi_loader: add PE/COFF image measurement In-Reply-To: <20210415133020.29175-1-masahisa.kojima@linaro.org> References: <20210415133020.29175-1-masahisa.kojima@linaro.org> Message-ID: <20210415133020.29175-3-masahisa.kojima@linaro.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de "TCG PC Client Platform Firmware Profile Specification" requires to measure every attempt to load and execute a OS Loader(a UEFI application) into PCR[4]. This commit adds the PE/COFF image measurement, extends PCR, and appends measurement into Event Log. Signed-off-by: Masahisa Kojima --- include/efi_loader.h | 4 + include/efi_tcg2.h | 10 ++ include/tpm-v2.h | 1 + lib/efi_loader/efi_image_loader.c | 7 ++ lib/efi_loader/efi_tcg2.c | 187 ++++++++++++++++++++++++++++-- 5 files changed, 199 insertions(+), 10 deletions(-) diff --git a/include/efi_loader.h b/include/efi_loader.h index de1a496a97..b02bc93c8e 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -426,6 +426,10 @@ efi_status_t efi_disk_register(void); efi_status_t efi_rng_register(void); /* Called by efi_init_obj_list() to install EFI_TCG2_PROTOCOL */ efi_status_t efi_tcg2_register(void); +/* measure the pe-coff image, extend PCR and add Event Log */ +efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size, + struct efi_loaded_image_obj *handle, + struct efi_loaded_image *loaded_image_info); /* Create handles and protocols for the partitions of a block device */ int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc, const char *if_typename, int diskid, diff --git a/include/efi_tcg2.h b/include/efi_tcg2.h index 40e241ce31..f8d46c5fd2 100644 --- a/include/efi_tcg2.h +++ b/include/efi_tcg2.h @@ -9,6 +9,8 @@ #if !defined _EFI_TCG2_PROTOCOL_H_ #define _EFI_TCG2_PROTOCOL_H_ +#include +#include #include #define EFI_TCG2_PROTOCOL_GUID \ @@ -53,6 +55,14 @@ struct efi_tcg2_event { u8 event[]; } __packed; +struct uefi_image_load_event { + efi_physical_addr_t image_location_in_memory; + u64 image_length_in_memory; + u64 image_link_time_address; + u64 length_of_device_path; + struct efi_device_path device_path[]; +} __packed; + struct efi_tcg2_boot_service_capability { u8 size; struct efi_tcg2_version structure_version; diff --git a/include/tpm-v2.h b/include/tpm-v2.h index df67a196cf..ab9c04dc0a 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -61,6 +61,7 @@ struct udevice; #define EV_S_CRTM_VERSION ((u32)0x00000008) #define EV_CPU_MICROCODE ((u32)0x00000009) #define EV_TABLE_OF_DEVICES ((u32)0x0000000B) +#define EV_EFI_BOOT_SERVICES_APPLICATION ((u32)0x80000003) /* TPMS_TAGGED_PROPERTY Structure */ struct tpms_tagged_property { diff --git a/lib/efi_loader/efi_image_loader.c b/lib/efi_loader/efi_image_loader.c index 2c35cb5651..b032ec5dd8 100644 --- a/lib/efi_loader/efi_image_loader.c +++ b/lib/efi_loader/efi_image_loader.c @@ -829,6 +829,13 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, goto err; } +#if CONFIG_IS_ENABLED(EFI_TCG2_PROTOCOL) + /* Measure an PE/COFF image */ + if (tcg2_measure_pe_image(efi, efi_size, handle, + loaded_image_info)) + log_err("PE image measurement failed\n"); +#endif + /* Copy PE headers */ memcpy(efi_reloc, efi, sizeof(*dos) diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c index ed86a220fb..9fab07605f 100644 --- a/lib/efi_loader/efi_tcg2.c +++ b/lib/efi_loader/efi_tcg2.c @@ -13,8 +13,10 @@ #include #include #include +#include #include #include +#include #include #include #include @@ -709,6 +711,172 @@ out: return EFI_EXIT(ret); } +static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size, + struct tpml_digest_values *digest_list) +{ + IMAGE_NT_HEADERS32 *nt; + WIN_CERTIFICATE *wincerts = NULL; + size_t wincerts_len; + struct efi_image_regions *regs = NULL; + void *new_efi = NULL; + size_t new_efi_size; + u8 hash[TPM2_SHA512_DIGEST_SIZE]; + efi_status_t ret; + u32 active; + int i; + + ret = efi_check_pe(efi, efi_size, (void **)&nt); + if (ret != EFI_SUCCESS) { + log_err("Not a valid PE-COFF file\n"); + return EFI_INVALID_PARAMETER; + } + + /* + * Size must be 8-byte aligned and the trailing bytes must be + * zero'ed. Otherwise hash value may be incorrect. + */ + if (!IS_ALIGNED(efi_size, 8)) { + new_efi_size = ALIGN(efi_size, 8); + new_efi = calloc(new_efi_size, 1); + if (!new_efi) + return EFI_OUT_OF_RESOURCES; + memcpy(new_efi, efi, efi_size); + efi = new_efi; + efi_size = new_efi_size; + } + + if (!efi_image_parse(efi, efi_size, ®s, &wincerts, + &wincerts_len)) { + log_err("Parsing PE executable image failed\n"); + ret = EFI_INVALID_PARAMETER; + goto out; + } + + ret = __get_active_pcr_banks(&active); + if (ret != EFI_SUCCESS) { + ret = EFI_DEVICE_ERROR; + goto out; + } + + digest_list->count = 0; + for (i = 0; i < MAX_HASH_COUNT; i++) { + u16 hash_alg = hash_algo_list[i].hash_alg; + + if (!(active & alg_to_mask(hash_alg))) + continue; + switch (hash_alg) { + case TPM2_ALG_SHA1: + hash_calculate("sha1", regs->reg, regs->num, hash); + digest_list->count++; + break; + case TPM2_ALG_SHA256: + hash_calculate("sha256", regs->reg, regs->num, hash); + digest_list->count++; + break; + case TPM2_ALG_SHA384: + hash_calculate("sha384", regs->reg, regs->num, hash); + digest_list->count++; + break; + case TPM2_ALG_SHA512: + hash_calculate("sha512", regs->reg, regs->num, hash); + digest_list->count++; + break; + default: + 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)); + } + +out: + free(new_efi); + free(regs); + + return ret; +} + +efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size, + struct efi_loaded_image_obj *handle, + struct efi_loaded_image *loaded_image) +{ + struct tpml_digest_values digest_list; + efi_status_t ret; + struct udevice *dev; + u32 pcr_index, event_type, event_size; + struct uefi_image_load_event *image_load_event; + u8 *event; + struct efi_device_path *device_path; + u32 device_path_length; + IMAGE_DOS_HEADER *dos; + IMAGE_NT_HEADERS32 *nt; + + ret = platform_get_tpm2_device(&dev); + if (ret != EFI_SUCCESS) + return ret; + + if (handle->image_type == IMAGE_SUBSYSTEM_EFI_APPLICATION) { + pcr_index = 4; + event_type = EV_EFI_BOOT_SERVICES_APPLICATION; + } else { + return EFI_UNSUPPORTED; + } + + ret = tcg2_hash_pe_image(efi, efi_size, &digest_list); + if (ret != EFI_SUCCESS) + return ret; + + ret = tcg2_pcr_extend(dev, pcr_index, &digest_list); + if (ret != EFI_SUCCESS) + return ret; + + loaded_image->system_table->boottime->handle_protocol(&handle->header, + &efi_guid_loaded_image_device_path, + (void **)&device_path); + device_path_length = efi_dp_size(device_path); + if (device_path_length > 0) { + /* add end node size */ + device_path_length += sizeof(struct efi_device_path); + } + event_size = sizeof(struct uefi_image_load_event) + device_path_length; + event = malloc(event_size); + if (!event) + return EFI_OUT_OF_RESOURCES; + + image_load_event = (struct uefi_image_load_event *)event; + image_load_event->image_location_in_memory = (efi_physical_addr_t)efi; + image_load_event->image_length_in_memory = efi_size; + image_load_event->length_of_device_path = device_path_length; + + dos = (IMAGE_DOS_HEADER *)efi; + nt = (IMAGE_NT_HEADERS32 *)(efi + dos->e_lfanew); + if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) { + IMAGE_NT_HEADERS64 *nt64 = (IMAGE_NT_HEADERS64 *)nt; + + image_load_event->image_link_time_address = + nt64->OptionalHeader.ImageBase; + } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) { + image_load_event->image_link_time_address = + nt->OptionalHeader.ImageBase; + } else { + ret = EFI_INVALID_PARAMETER; + goto out; + } + + if (device_path_length > 0) { + memcpy(image_load_event->device_path, device_path, + device_path_length); + } + + ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list, + event_size, event); + +out: + free(event); + + return ret; +} + /** * efi_tcg2_hash_log_extend_event() - extend and optionally log events * @@ -761,24 +929,23 @@ efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags, /* * if PE_COFF_IMAGE is set we need to make sure the image is not * corrupted, verify it and hash the PE/COFF image in accordance with - * the procedure specified in "Calculating the PE Image Hash" - * section of the "Windows Authenticode Portable Executable Signature + * the procedure specified in "Calculating the PE Image Hash" + * section of the "Windows Authenticode Portable Executable Signature * Format" - * Not supported for now */ if (flags & PE_COFF_IMAGE) { - ret = EFI_UNSUPPORTED; - goto out; + ret = tcg2_hash_pe_image((void *)data_to_hash, data_to_hash_len, + &digest_list); + } else { + ret = tcg2_create_digest((u8 *)data_to_hash, data_to_hash_len, + &digest_list); } + if (ret != EFI_SUCCESS) + goto out; pcr_index = efi_tcg_event->header.pcr_index; event_type = efi_tcg_event->header.event_type; - ret = tcg2_create_digest((u8 *)data_to_hash, data_to_hash_len, - &digest_list); - if (ret != EFI_SUCCESS) - goto out; - ret = tcg2_pcr_extend(dev, pcr_index, &digest_list); if (ret != EFI_SUCCESS) goto out; -- 2.17.1