| /* |
| * Copyright 2016 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include <arch/early_variables.h> |
| #include <commonlib/endian.h> |
| #include <console/console.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "tpm2_marshaling.h" |
| |
| static uint16_t tpm_tag CAR_GLOBAL; /* Depends on the command type. */ |
| |
| /* |
| * Each unmarshaling function receives a pointer to the buffer pointer and a |
| * pointer to the size of data still in the buffer. The function extracts data |
| * from the buffer and adjusts both buffer pointer and remaining data size. |
| * |
| * Should there be not enough data in the buffer to unmarshal the required |
| * object, the remaining data size is set to -1 to indicate the error. The |
| * remaining data size is expected to be set to zero once the last data item |
| * has been extracted from the receive buffer. |
| */ |
| static uint16_t unmarshal_u16(void **buffer, int *buffer_space) |
| { |
| uint16_t value; |
| |
| if (*buffer_space < 0) |
| return 0; |
| |
| if (*buffer_space < sizeof(value)) { |
| *buffer_space = -1; /* Indicate a failure. */ |
| return 0; |
| } |
| |
| value = read_be16(*buffer); |
| *buffer = (void *) ((uintptr_t) (*buffer) + sizeof(value)); |
| *buffer_space -= sizeof(value); |
| |
| return value; |
| } |
| |
| static uint16_t unmarshal_u32(void **buffer, int *buffer_space) |
| { |
| uint32_t value; |
| |
| if (*buffer_space < 0) |
| return 0; |
| |
| if (*buffer_space < sizeof(value)) { |
| *buffer_space = -1; /* Indicate a failure. */ |
| return 0; |
| } |
| |
| value = read_be32(*buffer); |
| *buffer = (void *) ((uintptr_t) (*buffer) + sizeof(value)); |
| *buffer_space -= sizeof(value); |
| |
| return value; |
| } |
| |
| static uint8_t unmarshal_u8(void **buffer, int *buffer_space) |
| { |
| uint8_t value; |
| |
| if (*buffer_space < 0) |
| return 0; |
| |
| if (*buffer_space < sizeof(value)) { |
| *buffer_space = -1; /* Indicate a failure. */ |
| return 0; |
| } |
| |
| value = ((uint8_t *)(*buffer))[0]; |
| *buffer = (void *) ((uintptr_t) (*buffer) + sizeof(value)); |
| *buffer_space -= sizeof(value); |
| |
| return value; |
| } |
| |
| #define unmarshal_TPM_CAP(a, b) unmarshal_u32(a, b) |
| #define unmarshal_TPM_CC(a, b) unmarshal_u32(a, b) |
| #define unmarshal_TPM_PT(a, b) unmarshal_u32(a, b) |
| #define unmarshal_TPM_HANDLE(a, b) unmarshal_u32(a, b) |
| |
| /* |
| * Each marshaling function receives a pointer to the buffer to marshal into, |
| * a pointer to the data item to be marshaled, and a pointer to the remaining |
| * room in the buffer. |
| */ |
| |
| /* |
| * Marshaling an arbitrary blob requires its size in addition to common |
| * parameter set. |
| */ |
| static void marshal_blob(void **buffer, void *blob, |
| size_t blob_size, size_t *buffer_space) |
| { |
| if (*buffer_space < blob_size) { |
| *buffer_space = -1; |
| return; |
| } |
| |
| memcpy(*buffer, blob, blob_size); |
| *buffer_space -= blob_size; |
| *buffer = (void *)((uintptr_t)(*buffer) + blob_size); |
| } |
| |
| static void marshal_u8(void **buffer, uint8_t value, size_t *buffer_space) |
| { |
| uint8_t *bp = *buffer; |
| |
| if (*buffer_space < sizeof(value)) { |
| *buffer_space = 0; |
| return; |
| } |
| |
| *bp++ = value; |
| *buffer = bp; |
| *buffer_space -= sizeof(value); |
| } |
| |
| static void marshal_u16(void **buffer, uint16_t value, size_t *buffer_space) |
| { |
| if (*buffer_space < sizeof(value)) { |
| *buffer_space = 0; |
| return; |
| } |
| write_be16(*buffer, value); |
| *buffer = (void *)((uintptr_t)(*buffer) + sizeof(value)); |
| *buffer_space -= sizeof(value); |
| } |
| |
| static void marshal_u32(void **buffer, uint32_t value, size_t *buffer_space) |
| { |
| if (*buffer_space < sizeof(value)) { |
| *buffer_space = 0; |
| return; |
| } |
| |
| write_be32(*buffer, value); |
| *buffer = (void *)((uintptr_t)(*buffer) + sizeof(value)); |
| *buffer_space -= sizeof(value); |
| } |
| |
| #define marshal_TPM_HANDLE(a, b, c) marshal_u32(a, b, c) |
| #define marshal_TPMI_RH_NV_AUTH(a, b, c) marshal_TPM_HANDLE(a, b, c) |
| #define marshal_TPMI_RH_NV_INDEX(a, b, c) marshal_TPM_HANDLE(a, b, c) |
| #define marshal_TPMI_SH_AUTH_SESSION(a, b, c) marshal_TPM_HANDLE(a, b, c) |
| #define marshal_TPMI_ALG_HASH(a, b, c) marshal_u16(a, b, c) |
| |
| static void marshal_startup(void **buffer, |
| struct tpm2_startup *cmd_body, |
| size_t *buffer_space) |
| { |
| marshal_u16(buffer, cmd_body->startup_type, buffer_space); |
| } |
| |
| static void marshal_get_capability(void **buffer, |
| struct tpm2_get_capability *cmd_body, |
| size_t *buffer_space) |
| { |
| marshal_u32(buffer, cmd_body->capability, buffer_space); |
| marshal_u32(buffer, cmd_body->property, buffer_space); |
| marshal_u32(buffer, cmd_body->propertyCount, buffer_space); |
| } |
| |
| static void marshal_TPM2B(void **buffer, |
| TPM2B *data, |
| size_t *buffer_space) |
| { |
| size_t total_size = data->size + sizeof(data->size); |
| |
| if (total_size > *buffer_space) { |
| *buffer_space = 0; |
| return; |
| } |
| marshal_u16(buffer, data->size, buffer_space); |
| memcpy(*buffer, data->buffer, data->size); |
| *buffer = ((uint8_t *)(*buffer)) + data->size; |
| *buffer_space -= data->size; |
| } |
| |
| static void marshal_TPMA_NV(void **buffer, |
| TPMA_NV *nv, |
| size_t *buffer_space) |
| { |
| marshal_u32(buffer, *((uint32_t *)nv), buffer_space); |
| } |
| |
| static void marshal_TPMS_NV_PUBLIC(void **buffer, |
| TPMS_NV_PUBLIC *nvpub, |
| size_t *buffer_space) |
| { |
| marshal_TPM_HANDLE(buffer, nvpub->nvIndex, buffer_space); |
| marshal_TPMI_ALG_HASH(buffer, nvpub->nameAlg, buffer_space); |
| marshal_TPMA_NV(buffer, &nvpub->attributes, buffer_space); |
| marshal_TPM2B(buffer, &nvpub->authPolicy.b, buffer_space); |
| marshal_u16(buffer, nvpub->dataSize, buffer_space); |
| } |
| |
| static void marshal_TPMT_HA(void **buffer, |
| TPMT_HA *tpmtha, |
| size_t *buffer_space) |
| { |
| marshal_TPMI_ALG_HASH(buffer, tpmtha->hashAlg, buffer_space); |
| marshal_blob(buffer, tpmtha->digest.sha256, |
| sizeof(tpmtha->digest.sha256), |
| buffer_space); |
| } |
| |
| static void marshal_TPML_DIGEST_VALUES(void **buffer, |
| TPML_DIGEST_VALUES *dvalues, |
| size_t *buffer_space) |
| { |
| int i; |
| |
| marshal_u32(buffer, dvalues->count, buffer_space); |
| for (i = 0; i < dvalues->count; i++) |
| marshal_TPMT_HA(buffer, &dvalues->digests[i], buffer_space); |
| } |
| |
| static void marshal_session_header(void **buffer, |
| struct tpm2_session_header *session_header, |
| size_t *buffer_space) |
| { |
| size_t base_size; |
| void *size_location = *buffer; |
| |
| /* Skip room for the session header size. */ |
| if (*buffer_space < sizeof(uint32_t)) { |
| *buffer_space = 0; |
| return; |
| } |
| |
| *buffer_space -= sizeof(uint32_t); |
| *buffer = (void *)(((uintptr_t) *buffer) + sizeof(uint32_t)); |
| |
| base_size = *buffer_space; |
| |
| marshal_u32(buffer, session_header->session_handle, buffer_space); |
| marshal_u16(buffer, session_header->nonce_size, buffer_space); |
| marshal_blob(buffer, session_header->nonce, |
| session_header->nonce_size, buffer_space); |
| marshal_u8(buffer, session_header->session_attrs, buffer_space); |
| marshal_u16(buffer, session_header->auth_size, buffer_space); |
| marshal_blob(buffer, session_header->auth, |
| session_header->auth_size, buffer_space); |
| |
| if (!*buffer_space) |
| return; /* The structure did not fit. */ |
| |
| /* Paste in the session size. */ |
| marshal_u32(&size_location, base_size - *buffer_space, &base_size); |
| } |
| |
| /* |
| * Common session header can include one or two handles and an empty |
| * session_header structure. |
| */ |
| static void marshal_common_session_header(void **buffer, |
| const uint32_t *handles, |
| size_t handle_count, |
| size_t *buffer_space) |
| { |
| int i; |
| struct tpm2_session_header session_header; |
| |
| car_set_var(tpm_tag, TPM_ST_SESSIONS); |
| |
| for (i = 0; i < handle_count; i++) |
| marshal_TPM_HANDLE(buffer, handles[i], buffer_space); |
| |
| memset(&session_header, 0, sizeof(session_header)); |
| session_header.session_handle = TPM_RS_PW; |
| marshal_session_header(buffer, &session_header, buffer_space); |
| } |
| |
| static void marshal_nv_define_space(void **buffer, |
| struct tpm2_nv_define_space_cmd *nvd_in, |
| size_t *buffer_space) |
| { |
| void *size_location; |
| size_t base_size; |
| size_t sizeof_nv_public_size = sizeof(uint16_t); |
| const uint32_t handle[] = { TPM_RH_PLATFORM }; |
| |
| marshal_common_session_header(buffer, handle, |
| ARRAY_SIZE(handle), buffer_space); |
| marshal_TPM2B(buffer, &nvd_in->auth.b, buffer_space); |
| |
| /* This is where the TPMS_NV_PUBLIC size will be stored. */ |
| size_location = *buffer; |
| |
| /* Allocate room for the size. */ |
| *buffer = ((uint8_t *)(*buffer)) + sizeof(uint16_t); |
| |
| if (*buffer_space < sizeof_nv_public_size) { |
| *buffer_space = 0; |
| return; |
| } |
| *buffer_space -= sizeof_nv_public_size; |
| base_size = *buffer_space; |
| |
| marshal_TPMS_NV_PUBLIC(buffer, &nvd_in->publicInfo, buffer_space); |
| if (!*buffer_space) |
| return; |
| |
| base_size = base_size - *buffer_space; |
| marshal_u16(&size_location, base_size, &sizeof_nv_public_size); |
| } |
| |
| static void marshal_nv_write(void **buffer, |
| struct tpm2_nv_write_cmd *command_body, |
| size_t *buffer_space) |
| { |
| uint32_t handles[] = { TPM_RH_PLATFORM, command_body->nvIndex }; |
| |
| marshal_common_session_header(buffer, handles, |
| ARRAY_SIZE(handles), buffer_space); |
| marshal_TPM2B(buffer, &command_body->data.b, buffer_space); |
| marshal_u16(buffer, command_body->offset, buffer_space); |
| } |
| |
| static void marshal_nv_write_lock(void **buffer, |
| struct tpm2_nv_write_lock_cmd *command_body, |
| size_t *buffer_space) |
| { |
| uint32_t handles[] = { TPM_RH_PLATFORM, command_body->nvIndex }; |
| marshal_common_session_header(buffer, handles, |
| ARRAY_SIZE(handles), buffer_space); |
| } |
| |
| static void marshal_pcr_extend(void **buffer, |
| struct tpm2_pcr_extend_cmd *command_body, |
| size_t *buffer_space) |
| { |
| uint32_t handle = command_body->pcrHandle; |
| |
| marshal_common_session_header(buffer, &handle, 1, buffer_space); |
| marshal_TPML_DIGEST_VALUES(buffer, |
| &command_body->digests, buffer_space); |
| } |
| |
| static void marshal_nv_read(void **buffer, |
| struct tpm2_nv_read_cmd *command_body, |
| size_t *buffer_space) |
| { |
| uint32_t handles[] = { TPM_RH_PLATFORM, command_body->nvIndex }; |
| |
| marshal_common_session_header(buffer, handles, |
| ARRAY_SIZE(handles), buffer_space); |
| marshal_u16(buffer, command_body->size, buffer_space); |
| marshal_u16(buffer, command_body->offset, buffer_space); |
| } |
| |
| /* TPM2_Clear command does not require paramaters. */ |
| static void marshal_clear(void **buffer, size_t *buffer_space) |
| { |
| const uint32_t handle[] = { TPM_RH_PLATFORM }; |
| |
| marshal_common_session_header(buffer, handle, |
| ARRAY_SIZE(handle), buffer_space); |
| } |
| |
| static void marshal_selftest(void **buffer, |
| struct tpm2_self_test *command_body, |
| size_t *buffer_space) |
| { |
| marshal_u8(buffer, command_body->yes_no, buffer_space); |
| } |
| |
| int tpm_marshal_command(TPM_CC command, void *tpm_command_body, |
| void *buffer, size_t buffer_size) |
| { |
| void *cmd_body = (uint8_t *)buffer + sizeof(struct tpm_header); |
| size_t max_body_size = buffer_size - sizeof(struct tpm_header); |
| size_t body_size = max_body_size; |
| |
| /* Will be modified when marshaling some commands. */ |
| car_set_var(tpm_tag, TPM_ST_NO_SESSIONS); |
| |
| switch (command) { |
| case TPM2_Startup: |
| marshal_startup(&cmd_body, tpm_command_body, &body_size); |
| break; |
| |
| case TPM2_GetCapability: |
| marshal_get_capability(&cmd_body, tpm_command_body, |
| &body_size); |
| break; |
| |
| case TPM2_NV_Read: |
| marshal_nv_read(&cmd_body, tpm_command_body, &body_size); |
| break; |
| |
| case TPM2_NV_DefineSpace: |
| marshal_nv_define_space(&cmd_body, |
| tpm_command_body, &body_size); |
| break; |
| |
| case TPM2_NV_Write: |
| marshal_nv_write(&cmd_body, tpm_command_body, &body_size); |
| break; |
| |
| case TPM2_NV_WriteLock: |
| marshal_nv_write_lock(&cmd_body, tpm_command_body, &body_size); |
| break; |
| |
| case TPM2_SelfTest: |
| marshal_selftest(&cmd_body, tpm_command_body, &body_size); |
| break; |
| |
| case TPM2_Clear: |
| marshal_clear(&cmd_body, &body_size); |
| break; |
| |
| case TPM2_PCR_Extend: |
| marshal_pcr_extend(&cmd_body, tpm_command_body, &body_size); |
| break; |
| |
| default: |
| body_size = 0; |
| printk(BIOS_INFO, "%s:%d:Request to marshal unsupported command %#x\n", |
| __FILE__, __LINE__, command); |
| } |
| |
| if (body_size > 0) { |
| size_t marshaled_size; |
| size_t header_room = sizeof(struct tpm_header); |
| |
| /* See how much room was taken by marshaling. */ |
| marshaled_size = max_body_size - body_size; |
| |
| /* Total size includes the header size. */ |
| marshaled_size += sizeof(struct tpm_header); |
| |
| uint16_t tpm_tag_value = car_get_var(tpm_tag); |
| |
| marshal_u16(&buffer, tpm_tag_value, &header_room); |
| marshal_u32(&buffer, marshaled_size, &header_room); |
| marshal_u32(&buffer, command, &header_room); |
| return marshaled_size; |
| } |
| |
| return -1; |
| } |
| |
| static void unmarshal_get_capability(void **buffer, int *size, |
| struct get_cap_response *gcr) |
| { |
| int i; |
| |
| gcr->more_data = unmarshal_u8(buffer, size); |
| |
| gcr->cd.capability = unmarshal_TPM_CAP(buffer, size); |
| if (*size < 0) |
| return; |
| |
| switch (gcr->cd.capability) { |
| case TPM_CAP_TPM_PROPERTIES: |
| gcr->cd.data.tpmProperties.count = |
| unmarshal_u32(buffer, size); |
| if (*size < 0) |
| return; |
| if (gcr->cd.data.tpmProperties.count > ARRAY_SIZE |
| (gcr->cd.data.tpmProperties.tpmProperty)) { |
| printk(BIOS_INFO, "%s:%s:%d - %d - too many properties\n", |
| __FILE__, __func__, __LINE__, |
| gcr->cd.data.tpmProperties.count); |
| *size = -1; |
| return; |
| } |
| for (i = 0; i < gcr->cd.data.tpmProperties.count; i++) { |
| TPMS_TAGGED_PROPERTY *pp; |
| |
| pp = gcr->cd.data.tpmProperties.tpmProperty + i; |
| pp->property = unmarshal_TPM_PT(buffer, size); |
| pp->value = unmarshal_u32(buffer, size); |
| } |
| break; |
| default: |
| printk(BIOS_ERR, |
| "%s:%d - unable to unmarshal capability response", |
| __func__, __LINE__); |
| printk(BIOS_ERR, " for %d\n", gcr->cd.capability); |
| *size = -1; |
| break; |
| } |
| } |
| |
| static void unmarshal_TPM2B_MAX_NV_BUFFER(void **buffer, |
| int *size, |
| TPM2B_MAX_NV_BUFFER *nv_buffer) |
| { |
| nv_buffer->t.size = unmarshal_u16(buffer, size); |
| if ((*size < 0) || (nv_buffer->t.size > *size)) { |
| printk(BIOS_ERR, "%s:%d - " |
| "size mismatch: expected %d, remaining %d\n", |
| __func__, __LINE__, nv_buffer->t.size, *size); |
| *size = -1; |
| return; |
| } |
| |
| nv_buffer->t.buffer = *buffer; |
| |
| *buffer = ((uint8_t *)(*buffer)) + nv_buffer->t.size; |
| *size -= nv_buffer->t.size; |
| } |
| |
| static void unmarshal_nv_read(void **buffer, int *size, |
| struct nv_read_response *nvr) |
| { |
| /* Total size of the parameter field. */ |
| nvr->params_size = unmarshal_u32(buffer, size); |
| unmarshal_TPM2B_MAX_NV_BUFFER(buffer, size, &nvr->buffer); |
| |
| if (nvr->params_size != |
| (nvr->buffer.t.size + sizeof(nvr->buffer.t.size))) { |
| printk(BIOS_ERR, |
| "%s:%d - parameter/buffer %d/%d size mismatch", |
| __func__, __LINE__, nvr->params_size, |
| nvr->buffer.t.size); |
| return; |
| } |
| |
| if (*size < 0) |
| return; |
| /* |
| * Let's ignore the authorisation section. It should be 5 bytes total, |
| * just confirm that this is the case and report any discrepancy. |
| */ |
| if (*size != 5) |
| printk(BIOS_ERR, |
| "%s:%d - unexpected authorisation seciton size %d\n", |
| __func__, __LINE__, *size); |
| |
| *buffer = ((uint8_t *)(*buffer)) + *size; |
| *size = 0; |
| } |
| |
| struct tpm2_response *tpm_unmarshal_response(TPM_CC command, |
| void *response_body, |
| size_t in_size) |
| { |
| static struct tpm2_response tpm2_static_resp CAR_GLOBAL; |
| struct tpm2_response *tpm2_resp = car_get_var_ptr(&tpm2_static_resp); |
| /* |
| * Should be 0 when done, positive and negaitive values indicate |
| * unmarshaling errors. |
| */ |
| int cr_size = in_size; |
| |
| if ((cr_size < 0) || (in_size < sizeof(struct tpm_header))) |
| return NULL; |
| |
| tpm2_resp->hdr.tpm_tag = unmarshal_u16(&response_body, &cr_size); |
| tpm2_resp->hdr.tpm_size = unmarshal_u32(&response_body, &cr_size); |
| tpm2_resp->hdr.tpm_code = unmarshal_TPM_CC(&response_body, &cr_size); |
| |
| if (!cr_size) { |
| if (tpm2_resp->hdr.tpm_size != sizeof(tpm2_resp->hdr)) |
| printk(BIOS_ERR, |
| "%s: size mismatch in response to command %#x\n", |
| __func__, command); |
| return tpm2_resp; |
| } |
| |
| switch (command) { |
| case TPM2_Startup: |
| break; |
| |
| case TPM2_GetCapability: |
| unmarshal_get_capability(&response_body, &cr_size, |
| &tpm2_resp->gc); |
| break; |
| |
| case TPM2_NV_Read: |
| unmarshal_nv_read(&response_body, &cr_size, |
| &tpm2_resp->nvr); |
| break; |
| |
| case TPM2_Clear: |
| case TPM2_NV_DefineSpace: |
| case TPM2_NV_Write: |
| case TPM2_NV_WriteLock: |
| case TPM2_PCR_Extend: |
| /* Session data included in response can be safely ignored. */ |
| cr_size = 0; |
| break; |
| |
| default: |
| { |
| int i; |
| |
| printk(BIOS_INFO, "%s:%d:" |
| "Request to unmarshal unexpected command %#x," |
| " code %#x", |
| __func__, __LINE__, command, |
| tpm2_resp->hdr.tpm_code); |
| |
| for (i = 0; i < cr_size; i++) { |
| if (!(i % 16)) |
| printk(BIOS_INFO, "\n"); |
| printk(BIOS_INFO, "%2.2x ", |
| ((uint8_t *)response_body)[i]); |
| } |
| } |
| printk(BIOS_INFO, "\n"); |
| return NULL; |
| } |
| |
| if (cr_size) { |
| printk(BIOS_INFO, |
| "%s:%d got %d bytes back in response to %#x," |
| " failed to parse (%d)\n", |
| __func__, __LINE__, tpm2_resp->hdr.tpm_size, |
| command, cr_size); |
| return NULL; |
| } |
| |
| /* The entire message have been parsed. */ |
| return tpm2_resp; |
| } |