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-rw-r--r--src/security/tpm/tcg-1.2/tss.c353
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diff --git a/src/security/tpm/tcg-1.2/tss.c b/src/security/tpm/tcg-1.2/tss.c
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+++ b/src/security/tpm/tcg-1.2/tss.c
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+/* 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 <arch/early_variables.h>
+#include <assert.h>
+#include <string.h>
+#include <security/tpm/tis.h>
+#include <vb2_api.h>
+#include "tss_internal.h"
+#include "tss_structures.h"
+#include "../tss.h"
+
+#ifdef FOR_TEST
+#include <stdio.h>
+#define VBDEBUG(format, args...) printf(format, ## args)
+#else
+#include <console/console.h>
+#define VBDEBUG(format, args...) printk(BIOS_DEBUG, format, ## args)
+#endif
+
+static int tpm_send_receive(const uint8_t *request,
+ uint32_t request_length,
+ uint8_t *response,
+ uint32_t *response_length)
+{
+ size_t len = *response_length;
+ if (tis_sendrecv(request, request_length, response, &len))
+ return VB2_ERROR_UNKNOWN;
+ /* check 64->32bit overflow and (re)check response buffer overflow */
+ if (len > *response_length)
+ return VB2_ERROR_UNKNOWN;
+ *response_length = len;
+ return VB2_SUCCESS;
+}
+
+/* Sets the size field of a TPM command. */
+static inline void set_tpm_command_size(uint8_t *buffer, uint32_t size)
+{
+ to_tpm_uint32(buffer + sizeof(uint16_t), size);
+}
+
+/* Gets the size field of a TPM command. */
+__attribute__((unused))
+static inline int tpm_command_size(const uint8_t *buffer)
+{
+ uint32_t size;
+ from_tpm_uint32(buffer + sizeof(uint16_t), &size);
+ return (int) size;
+}
+
+/* Gets the code field of a TPM command. */
+static inline int tpm_command_code(const uint8_t *buffer)
+{
+ uint32_t code;
+ from_tpm_uint32(buffer + sizeof(uint16_t) + sizeof(uint32_t), &code);
+ return code;
+}
+
+/* Gets the return code field of a TPM result. */
+static inline int tpm_return_code(const uint8_t *buffer)
+{
+ return tpm_command_code(buffer);
+}
+
+/* Like TlclSendReceive below, but do not retry if NEEDS_SELFTEST or
+ * DOING_SELFTEST errors are returned.
+ */
+static uint32_t tlcl_send_receive_no_retry(const uint8_t *request,
+ uint8_t *response, int max_length)
+{
+ uint32_t response_length = max_length;
+ uint32_t result;
+
+ result = tpm_send_receive(request, tpm_command_size(request),
+ response, &response_length);
+ if (result != 0) {
+ /* Communication with TPM failed, so response is garbage */
+ VBDEBUG("TPM: command 0x%x send/receive failed: 0x%x\n",
+ tpm_command_code(request), result);
+ return result;
+ }
+ /* Otherwise, use the result code from the response */
+ result = tpm_return_code(response);
+
+ /* TODO: add paranoia about returned response_length vs. max_length
+ * (and possibly expected length from the response header). See
+ * crosbug.com/17017 */
+
+ VBDEBUG("TPM: command 0x%x returned 0x%x\n",
+ tpm_command_code(request), result);
+
+return result;
+}
+
+
+/* Sends a TPM command and gets a response. Returns 0 if success or the TPM
+ * error code if error. Waits for the self test to complete if needed. */
+uint32_t tlcl_send_receive(const uint8_t *request, uint8_t *response,
+ int max_length)
+{
+ uint32_t result = tlcl_send_receive_no_retry(request, response,
+ max_length);
+ /* 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 = tlcl_continue_self_test();
+ if (result != TPM_SUCCESS)
+ return result;
+#if defined(TPM_BLOCKING_CONTINUESELFTEST) || defined(VB_RECOVERY_MODE)
+ /* Retry only once */
+ result = tlcl_send_receive_no_retry(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 = tlcl_send_receive_no_retry(request, response,
+ max_length);
+ } while (result == TPM_E_DOING_SELFTEST);
+#endif
+ }
+ 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 tlcl_send_receive(command, response, sizeof(response));
+}
+
+/* Exported functions. */
+
+static uint8_t tlcl_init_done CAR_GLOBAL;
+
+uint32_t tlcl_lib_init(void)
+{
+ uint8_t done = car_get_var(tlcl_init_done);
+ if (done)
+ return VB2_SUCCESS;
+
+ if (tis_init())
+ return VB2_ERROR_UNKNOWN;
+ if (tis_open())
+ return VB2_ERROR_UNKNOWN;
+
+ car_set_var(tlcl_init_done, 1);
+
+ return VB2_SUCCESS;
+}
+
+uint32_t tlcl_startup(void)
+{
+ VBDEBUG("TPM: Startup\n");
+ return send(tpm_startup_cmd.buffer);
+}
+
+uint32_t tlcl_resume(void)
+{
+ VBDEBUG("TPM: Resume\n");
+ return send(tpm_resume_cmd.buffer);
+}
+
+uint32_t tlcl_self_test_full(void)
+{
+ VBDEBUG("TPM: Self test full\n");
+ return send(tpm_selftestfull_cmd.buffer);
+}
+
+uint32_t tlcl_continue_self_test(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 tlcl_send_receive_no_retry(tpm_continueselftest_cmd.buffer,
+ response, sizeof(response));
+}
+
+uint32_t tlcl_define_space(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));
+ to_tpm_uint32(cmd.buffer + tpm_nv_definespace_cmd.index, index);
+ to_tpm_uint32(cmd.buffer + tpm_nv_definespace_cmd.perm, perm);
+ to_tpm_uint32(cmd.buffer + tpm_nv_definespace_cmd.size, size);
+ return send(cmd.buffer);
+}
+
+uint32_t tlcl_write(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: tlcl_write(0x%x, %d)\n", index, length);
+ memcpy(&cmd, &tpm_nv_write_cmd, sizeof(cmd));
+ assert(total_length <= TPM_LARGE_ENOUGH_COMMAND_SIZE);
+ set_tpm_command_size(cmd.buffer, total_length);
+
+ to_tpm_uint32(cmd.buffer + tpm_nv_write_cmd.index, index);
+ to_tpm_uint32(cmd.buffer + tpm_nv_write_cmd.length, length);
+ memcpy(cmd.buffer + tpm_nv_write_cmd.data, data, length);
+
+ return tlcl_send_receive(cmd.buffer, response, sizeof(response));
+}
+
+uint32_t tlcl_read(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: tlcl_read(0x%x, %d)\n", index, length);
+ memcpy(&cmd, &tpm_nv_read_cmd, sizeof(cmd));
+ to_tpm_uint32(cmd.buffer + tpm_nv_read_cmd.index, index);
+ to_tpm_uint32(cmd.buffer + tpm_nv_read_cmd.length, length);
+
+ result = tlcl_send_receive(cmd.buffer, response, sizeof(response));
+ if (result == TPM_SUCCESS && length > 0) {
+ uint8_t *nv_read_cursor = response + kTpmResponseHeaderLength;
+ from_tpm_uint32(nv_read_cursor, &result_length);
+ nv_read_cursor += sizeof(uint32_t);
+ memcpy(data, nv_read_cursor, result_length);
+ }
+
+ return result;
+}
+
+
+uint32_t tlcl_assert_physical_presence(void)
+{
+ VBDEBUG("TPM: Asserting physical presence\n");
+ return send(tpm_ppassert_cmd.buffer);
+}
+
+uint32_t tlcl_physical_presence_cmd_enable(void)
+{
+ VBDEBUG("TPM: Enable the physical presence command\n");
+ return send(tpm_ppenable_cmd.buffer);
+}
+
+uint32_t tlcl_finalize_physical_presence(void)
+{
+ VBDEBUG("TPM: Enable PP cmd, disable HW pp, and set lifetime lock\n");
+ return send(tpm_finalizepp_cmd.buffer);
+}
+
+uint32_t tlcl_set_nv_locked(void)
+{
+ VBDEBUG("TPM: Set NV locked\n");
+ return tlcl_define_space(TPM_NV_INDEX_LOCK, 0, 0);
+}
+
+uint32_t tlcl_force_clear(void)
+{
+ VBDEBUG("TPM: Force clear\n");
+ return send(tpm_forceclear_cmd.buffer);
+}
+
+uint32_t tlcl_set_enable(void)
+{
+ VBDEBUG("TPM: Enabling TPM\n");
+ return send(tpm_physicalenable_cmd.buffer);
+}
+
+uint32_t tlcl_set_deactivated(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 tlcl_get_permanent_flags(TPM_PERMANENT_FLAGS *pflags)
+{
+ uint8_t response[TPM_LARGE_ENOUGH_COMMAND_SIZE];
+ uint32_t size;
+ uint32_t result = tlcl_send_receive(tpm_getflags_cmd.buffer, response,
+ sizeof(response));
+ if (result != TPM_SUCCESS)
+ return result;
+ from_tpm_uint32(response + kTpmResponseHeaderLength, &size);
+ assert(size == sizeof(TPM_PERMANENT_FLAGS));
+ memcpy(pflags, response + kTpmResponseHeaderLength + sizeof(size),
+ sizeof(TPM_PERMANENT_FLAGS));
+ return result;
+}
+
+uint32_t tlcl_get_flags(uint8_t *disable, uint8_t *deactivated,
+ uint8_t *nvlocked)
+{
+ TPM_PERMANENT_FLAGS pflags;
+ uint32_t result = tlcl_get_permanent_flags(&pflags);
+ if (result == TPM_SUCCESS) {
+ if (disable)
+ *disable = pflags.disable;
+ if (deactivated)
+ *deactivated = pflags.deactivated;
+ if (nvlocked)
+ *nvlocked = pflags.nvLocked;
+ VBDEBUG("TPM: flags disable=%d, deactivated=%d, nvlocked=%d\n",
+ pflags.disable, pflags.deactivated, pflags.nvLocked);
+ }
+ return result;
+}
+
+uint32_t tlcl_set_global_lock(void)
+{
+ uint32_t x;
+ VBDEBUG("TPM: Set global lock\n");
+ return tlcl_write(TPM_NV_INDEX0, (uint8_t *) &x, 0);
+}
+
+uint32_t tlcl_extend(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));
+ to_tpm_uint32(cmd.buffer + tpm_extend_cmd.pcrNum, pcr_num);
+ memcpy(cmd.buffer + cmd.inDigest, in_digest, kPcrDigestLength);
+
+ result = tlcl_send_receive(cmd.buffer, response, sizeof(response));
+ if (result != TPM_SUCCESS)
+ return result;
+
+ if (out_digest)
+ memcpy(out_digest, response + kTpmResponseHeaderLength,
+ kPcrDigestLength);
+ return result;
+}