| /* Copyright (c) 2012 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. |
| */ |
| |
| /* A lightweight TPM command library. |
| * |
| * The general idea is that TPM commands are array of bytes whose |
| * fields are mostly compile-time constant. The goal is to build much |
| * of the commands at compile time (or build time) and change some of |
| * the fields at run time as needed. The code in |
| * utility/tlcl_generator.c builds structures containing the commands, |
| * as well as the offsets of the fields that need to be set at run |
| * time. |
| */ |
| |
| #include "sysincludes.h" |
| |
| #include "tlcl.h" |
| #include "tlcl_internal.h" |
| #include "tlcl_structures.h" |
| #include "utility.h" |
| #include "vboot_api.h" |
| |
| #ifdef FOR_TEST |
| /* Allow unit testing implementation of TlclSendReceive() */ |
| #undef CHROMEOS_ENVIRONMENT |
| #endif |
| |
| /* Sets the size field of a TPM command. */ |
| static inline void SetTpmCommandSize(uint8_t* buffer, uint32_t size) { |
| ToTpmUint32(buffer + sizeof(uint16_t), size); |
| } |
| |
| /* Gets the size field of a TPM command. */ |
| __attribute__((unused)) |
| static inline int TpmCommandSize(const uint8_t* buffer) { |
| uint32_t size; |
| FromTpmUint32(buffer + sizeof(uint16_t), &size); |
| return (int) size; |
| } |
| |
| /* Gets the size field of a TPM request or response. */ |
| int TlclPacketSize(const uint8_t* packet) { |
| return TpmCommandSize(packet); |
| } |
| |
| /* Gets the code field of a TPM command. */ |
| static inline int TpmCommandCode(const uint8_t* buffer) { |
| uint32_t code; |
| FromTpmUint32(buffer + sizeof(uint16_t) + sizeof(uint32_t), &code); |
| return code; |
| } |
| |
| /* Gets the return code field of a TPM result. */ |
| static inline int TpmReturnCode(const uint8_t* buffer) { |
| return TpmCommandCode(buffer); |
| } |
| |
| /* Like TlclSendReceive below, but do not retry if NEEDS_SELFTEST or |
| * DOING_SELFTEST errors are returned. |
| */ |
| static uint32_t TlclSendReceiveNoRetry(const uint8_t* request, |
| uint8_t* response, int max_length) { |
| |
| uint32_t response_length = max_length; |
| uint32_t result; |
| |
| #ifdef EXTRA_LOGGING |
| VBDEBUG(("TPM: command: %x%x %x%x%x%x %x%x%x%x\n", |
| request[0], request[1], |
| request[2], request[3], request[4], request[5], |
| request[6], request[7], request[8], request[9])); |
| #endif |
| |
| result = VbExTpmSendReceive(request, TpmCommandSize(request), |
| response, &response_length); |
| if (0 != result) { |
| /* Communication with TPM failed, so response is garbage */ |
| VBDEBUG(("TPM: command 0x%x send/receive failed: 0x%x\n", |
| TpmCommandCode(request), result)); |
| return result; |
| } |
| /* Otherwise, use the result code from the response */ |
| result = TpmReturnCode(response); |
| |
| /* TODO: add paranoia about returned response_length vs. max_length |
| * (and possibly expected length from the response header). See |
| * crosbug.com/17017 */ |
| |
| #ifdef EXTRA_LOGGING |
| VBDEBUG(("TPM: response: %x%x %x%x%x%x %x%x%x%x\n", |
| response[0], response[1], |
| response[2], response[3], response[4], response[5], |
| response[6], response[7], response[8], response[9])); |
| #endif |
| |
| VBDEBUG(("TPM: command 0x%x returned 0x%x\n", |
| TpmCommandCode(request), result)); |
| |
| return result; |
| } |
| |
| |
| /* Sends a TPM command and gets a response. Returns 0 if success or the TPM |
| * error code if error. In the firmware, waits for the self test to complete |
| * if needed. In the host, reports the first error without retries. */ |
| uint32_t TlclSendReceive(const uint8_t* request, uint8_t* response, |
| int max_length) { |
| uint32_t result = TlclSendReceiveNoRetry(request, response, max_length); |
| /* When compiling for the firmware, hide command failures due to the self |
| * test not having run or completed. */ |
| #ifndef CHROMEOS_ENVIRONMENT |
| /* If the command fails because the self test has not completed, try it |
| * again after attempting to ensure that the self test has completed. */ |
| if (result == TPM_E_NEEDS_SELFTEST || result == TPM_E_DOING_SELFTEST) { |
| result = TlclContinueSelfTest(); |
| if (result != TPM_SUCCESS) { |
| return result; |
| } |
| #if defined(TPM_BLOCKING_CONTINUESELFTEST) || defined(VB_RECOVERY_MODE) |
| /* Retry only once */ |
| result = TlclSendReceiveNoRetry(request, response, max_length); |
| #else |
| /* This needs serious testing. The TPM specification says: "iii. The |
| * caller MUST wait for the actions of TPM_ContinueSelfTest to complete |
| * before reissuing the command C1." But, if ContinueSelfTest is |
| * non-blocking, how do we know that the actions have completed other than |
| * trying again? */ |
| do { |
| result = TlclSendReceiveNoRetry(request, response, max_length); |
| } while (result == TPM_E_DOING_SELFTEST); |
| #endif |
| } |
| #endif /* ! defined(CHROMEOS_ENVIRONMENT) */ |
| return result; |
| } |
| |
| /* Sends a command and returns the error code. */ |
| static uint32_t Send(const uint8_t* command) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| return TlclSendReceive(command, response, sizeof(response)); |
| } |
| |
| /* Exported functions. */ |
| |
| uint32_t TlclLibInit(void) { |
| return VbExTpmInit(); |
| } |
| |
| uint32_t TlclLibClose(void) { |
| return VbExTpmClose(); |
| } |
| |
| uint32_t TlclStartup(void) { |
| VBDEBUG(("TPM: Startup\n")); |
| return Send(tpm_startup_cmd.buffer); |
| } |
| |
| uint32_t TlclSaveState(void) { |
| VBDEBUG(("TPM: SaveState\n")); |
| return Send(tpm_savestate_cmd.buffer); |
| } |
| |
| uint32_t TlclResume(void) { |
| VBDEBUG(("TPM: Resume\n")); |
| return Send(tpm_resume_cmd.buffer); |
| } |
| |
| uint32_t TlclSelfTestFull(void) { |
| VBDEBUG(("TPM: Self test full\n")); |
| return Send(tpm_selftestfull_cmd.buffer); |
| } |
| |
| uint32_t TlclContinueSelfTest(void) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| VBDEBUG(("TPM: Continue self test\n")); |
| /* Call the No Retry version of SendReceive to avoid recursion. */ |
| return TlclSendReceiveNoRetry(tpm_continueselftest_cmd.buffer, |
| response, sizeof(response)); |
| } |
| |
| uint32_t TlclDefineSpace(uint32_t index, uint32_t perm, uint32_t size) { |
| struct s_tpm_nv_definespace_cmd cmd; |
| VBDEBUG(("TPM: TlclDefineSpace(0x%x, 0x%x, %d)\n", index, perm, size)); |
| Memcpy(&cmd, &tpm_nv_definespace_cmd, sizeof(cmd)); |
| ToTpmUint32(cmd.buffer + tpm_nv_definespace_cmd.index, index); |
| ToTpmUint32(cmd.buffer + tpm_nv_definespace_cmd.perm, perm); |
| ToTpmUint32(cmd.buffer + tpm_nv_definespace_cmd.size, size); |
| return Send(cmd.buffer); |
| } |
| |
| uint32_t TlclWrite(uint32_t index, const void* data, uint32_t length) { |
| struct s_tpm_nv_write_cmd cmd; |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| const int total_length = |
| kTpmRequestHeaderLength + kWriteInfoLength + length; |
| |
| VBDEBUG(("TPM: TlclWrite(0x%x, %d)\n", index, length)); |
| Memcpy(&cmd, &tpm_nv_write_cmd, sizeof(cmd)); |
| VbAssert(total_length <= TPM_LARGE_ENOUGH_COMMAND_SIZE); |
| SetTpmCommandSize(cmd.buffer, total_length); |
| |
| ToTpmUint32(cmd.buffer + tpm_nv_write_cmd.index, index); |
| ToTpmUint32(cmd.buffer + tpm_nv_write_cmd.length, length); |
| Memcpy(cmd.buffer + tpm_nv_write_cmd.data, data, length); |
| |
| return TlclSendReceive(cmd.buffer, response, sizeof(response)); |
| } |
| |
| uint32_t TlclRead(uint32_t index, void* data, uint32_t length) { |
| struct s_tpm_nv_read_cmd cmd; |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint32_t result_length; |
| uint32_t result; |
| |
| VBDEBUG(("TPM: TlclRead(0x%x, %d)\n", index, length)); |
| Memcpy(&cmd, &tpm_nv_read_cmd, sizeof(cmd)); |
| ToTpmUint32(cmd.buffer + tpm_nv_read_cmd.index, index); |
| ToTpmUint32(cmd.buffer + tpm_nv_read_cmd.length, length); |
| |
| result = TlclSendReceive(cmd.buffer, response, sizeof(response)); |
| if (result == TPM_SUCCESS && length > 0) { |
| uint8_t* nv_read_cursor = response + kTpmResponseHeaderLength; |
| FromTpmUint32(nv_read_cursor, &result_length); |
| nv_read_cursor += sizeof(uint32_t); |
| Memcpy(data, nv_read_cursor, result_length); |
| } |
| |
| return result; |
| } |
| |
| uint32_t TlclPCRRead(uint32_t index, void* data, uint32_t length) { |
| struct s_tpm_pcr_read_cmd cmd; |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint32_t result; |
| |
| VBDEBUG(("TPM: TlclPCRRead(0x%x, %d)\n", index, length)); |
| if (length < kPcrDigestLength) { |
| return TPM_E_IOERROR; |
| } |
| Memcpy(&cmd, &tpm_pcr_read_cmd, sizeof(cmd)); |
| ToTpmUint32(cmd.buffer + tpm_pcr_read_cmd.pcrNum, index); |
| |
| result = TlclSendReceive(cmd.buffer, response, sizeof(response)); |
| if (result == TPM_SUCCESS) { |
| uint8_t* pcr_read_cursor = response + kTpmResponseHeaderLength; |
| Memcpy(data, pcr_read_cursor, kPcrDigestLength); |
| } |
| |
| return result; |
| } |
| |
| uint32_t TlclWriteLock(uint32_t index) { |
| VBDEBUG(("TPM: Write lock 0x%x\n", index)); |
| return TlclWrite(index, NULL, 0); |
| } |
| |
| uint32_t TlclReadLock(uint32_t index) { |
| VBDEBUG(("TPM: Read lock 0x%x\n", index)); |
| return TlclRead(index, NULL, 0); |
| } |
| |
| uint32_t TlclAssertPhysicalPresence(void) { |
| VBDEBUG(("TPM: Asserting physical presence\n")); |
| return Send(tpm_ppassert_cmd.buffer); |
| } |
| |
| uint32_t TlclPhysicalPresenceCMDEnable(void) { |
| VBDEBUG(("TPM: Enable the physical presence command\n")); |
| return Send(tpm_ppenable_cmd.buffer); |
| } |
| |
| uint32_t TlclFinalizePhysicalPresence(void) { |
| VBDEBUG(("TPM: Enable PP cmd, disable HW pp, and set lifetime lock\n")); |
| return Send(tpm_finalizepp_cmd.buffer); |
| } |
| |
| uint32_t TlclAssertPhysicalPresenceResult(void) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| return TlclSendReceive(tpm_ppassert_cmd.buffer, response, sizeof(response)); |
| } |
| |
| uint32_t TlclLockPhysicalPresence(void) { |
| VBDEBUG(("TPM: Lock physical presence\n")); |
| return Send(tpm_pplock_cmd.buffer); |
| } |
| |
| uint32_t TlclSetNvLocked(void) { |
| VBDEBUG(("TPM: Set NV locked\n")); |
| return TlclDefineSpace(TPM_NV_INDEX_LOCK, 0, 0); |
| } |
| |
| int TlclIsOwned(void) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE + TPM_PUBEK_SIZE]; |
| uint32_t result; |
| result = TlclSendReceive(tpm_readpubek_cmd.buffer, |
| response, sizeof(response)); |
| return (result != TPM_SUCCESS); |
| } |
| |
| uint32_t TlclForceClear(void) { |
| VBDEBUG(("TPM: Force clear\n")); |
| return Send(tpm_forceclear_cmd.buffer); |
| } |
| |
| uint32_t TlclSetEnable(void) { |
| VBDEBUG(("TPM: Enabling TPM\n")); |
| return Send(tpm_physicalenable_cmd.buffer); |
| } |
| |
| uint32_t TlclClearEnable(void) { |
| VBDEBUG(("TPM: Disabling TPM\n")); |
| return Send(tpm_physicaldisable_cmd.buffer); |
| } |
| |
| uint32_t TlclSetDeactivated(uint8_t flag) { |
| struct s_tpm_physicalsetdeactivated_cmd cmd; |
| VBDEBUG(("TPM: SetDeactivated(%d)\n", flag)); |
| Memcpy(&cmd, &tpm_physicalsetdeactivated_cmd, sizeof(cmd)); |
| *(cmd.buffer + cmd.deactivated) = flag; |
| return Send(cmd.buffer); |
| } |
| |
| uint32_t TlclGetPermanentFlags(TPM_PERMANENT_FLAGS* pflags) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint32_t size; |
| uint32_t result = |
| TlclSendReceive(tpm_getflags_cmd.buffer, response, sizeof(response)); |
| if (result != TPM_SUCCESS) |
| return result; |
| FromTpmUint32(response + kTpmResponseHeaderLength, &size); |
| /* TODO(crbug.com/379255): This fails. Find out why. |
| * VbAssert(size == sizeof(TPM_PERMANENT_FLAGS)); |
| */ |
| Memcpy(pflags, |
| response + kTpmResponseHeaderLength + sizeof(size), |
| sizeof(TPM_PERMANENT_FLAGS)); |
| return result; |
| } |
| |
| uint32_t TlclGetSTClearFlags(TPM_STCLEAR_FLAGS* vflags) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint32_t size; |
| uint32_t result = |
| TlclSendReceive(tpm_getstclearflags_cmd.buffer, response, sizeof(response)); |
| if (result != TPM_SUCCESS) |
| return result; |
| FromTpmUint32(response + kTpmResponseHeaderLength, &size); |
| /* Ugly assertion, but the struct is padded up by one byte. */ |
| /* TODO(crbug.com/379255): This fails. Find out why. |
| * VbAssert(size == 7 && sizeof(TPM_STCLEAR_FLAGS) - 1 == 7); |
| */ |
| Memcpy(vflags, |
| response + kTpmResponseHeaderLength + sizeof(size), |
| sizeof(TPM_STCLEAR_FLAGS)); |
| return result; |
| } |
| |
| uint32_t TlclGetFlags(uint8_t* disable, |
| uint8_t* deactivated, |
| uint8_t *nvlocked) { |
| TPM_PERMANENT_FLAGS pflags; |
| uint32_t result = TlclGetPermanentFlags(&pflags); |
| if (result == TPM_SUCCESS) { |
| if (disable) |
| *disable = pflags.disable; |
| if (deactivated) |
| *deactivated = pflags.deactivated; |
| if (nvlocked) |
| *nvlocked = pflags.nvLocked; |
| VBDEBUG(("TPM: Got flags disable=%d, deactivated=%d, nvlocked=%d\n", |
| pflags.disable, pflags.deactivated, pflags.nvLocked)); |
| } |
| return result; |
| } |
| |
| uint32_t TlclSetGlobalLock(void) { |
| uint32_t x; |
| VBDEBUG(("TPM: Set global lock\n")); |
| return TlclWrite(TPM_NV_INDEX0, (uint8_t*) &x, 0); |
| } |
| |
| uint32_t TlclExtend(int pcr_num, const uint8_t* in_digest, |
| uint8_t* out_digest) { |
| struct s_tpm_extend_cmd cmd; |
| uint8_t response[kTpmResponseHeaderLength + kPcrDigestLength]; |
| uint32_t result; |
| |
| Memcpy(&cmd, &tpm_extend_cmd, sizeof(cmd)); |
| ToTpmUint32(cmd.buffer + tpm_extend_cmd.pcrNum, pcr_num); |
| Memcpy(cmd.buffer + cmd.inDigest, in_digest, kPcrDigestLength); |
| |
| result = TlclSendReceive(cmd.buffer, response, sizeof(response)); |
| if (result != TPM_SUCCESS) |
| return result; |
| |
| Memcpy(out_digest, response + kTpmResponseHeaderLength, kPcrDigestLength); |
| return result; |
| } |
| |
| uint32_t TlclGetPermissions(uint32_t index, uint32_t* permissions) { |
| struct s_tpm_getpermissions_cmd cmd; |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint8_t* nvdata; |
| uint32_t result; |
| uint32_t size; |
| |
| Memcpy(&cmd, &tpm_getpermissions_cmd, sizeof(cmd)); |
| ToTpmUint32(cmd.buffer + tpm_getpermissions_cmd.index, index); |
| result = TlclSendReceive(cmd.buffer, response, sizeof(response)); |
| if (result != TPM_SUCCESS) |
| return result; |
| |
| nvdata = response + kTpmResponseHeaderLength + sizeof(size); |
| FromTpmUint32(nvdata + kNvDataPublicPermissionsOffset, permissions); |
| return result; |
| } |
| |
| uint32_t TlclGetOwnership(uint8_t* owned) { |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint32_t size; |
| uint32_t result = |
| TlclSendReceive(tpm_getownership_cmd.buffer, response, sizeof(response)); |
| if (result != TPM_SUCCESS) |
| return result; |
| FromTpmUint32(response + kTpmResponseHeaderLength, &size); |
| /* TODO(crbug.com/379255): This fails. Find out why. |
| * VbAssert(size == sizeof(*owned)); |
| */ |
| Memcpy(owned, |
| response + kTpmResponseHeaderLength + sizeof(size), |
| sizeof(*owned)); |
| return result; |
| } |
| |
| uint32_t TlclGetRandom(uint8_t* data, uint32_t length, uint32_t *size) { |
| struct s_tpm_get_random_cmd cmd; |
| uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE]; |
| uint32_t result; |
| |
| VBDEBUG(("TPM: TlclGetRandom(%d)\n", length)); |
| Memcpy(&cmd, &tpm_get_random_cmd, sizeof(cmd)); |
| ToTpmUint32(cmd.buffer + tpm_get_random_cmd.bytesRequested, length); |
| /* There must be room in the response buffer for the bytes. */ |
| if (length > TPM_LARGE_ENOUGH_COMMAND_SIZE - kTpmResponseHeaderLength |
| - sizeof(uint32_t)) { |
| return TPM_E_IOERROR; |
| } |
| |
| result = TlclSendReceive(cmd.buffer, response, sizeof(response)); |
| if (result == TPM_SUCCESS) { |
| uint8_t* get_random_cursor; |
| FromTpmUint32(response + kTpmResponseHeaderLength, size); |
| |
| /* There must be room in the target buffer for the bytes. */ |
| if (*size > length) { |
| return TPM_E_RESPONSE_TOO_LARGE; |
| } |
| get_random_cursor = response + kTpmResponseHeaderLength |
| + sizeof(uint32_t); |
| Memcpy(data, get_random_cursor, *size); |
| } |
| |
| return result; |
| } |