You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
170 lines
4.6 KiB
170 lines
4.6 KiB
/* Copyright (c) 2013 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.
|
|
*
|
|
* Functions for updating the TPM state with the status of boot path.
|
|
*/
|
|
|
|
#include "sysincludes.h"
|
|
|
|
#include "tlcl.h"
|
|
#include "tpm_bootmode.h"
|
|
#include "utility.h"
|
|
#include "vboot_api.h"
|
|
|
|
/* TPM PCRs to use for storing boot mode measurements. */
|
|
#define BOOT_MODE_PCR 0
|
|
#define HWID_DIGEST_PCR 1
|
|
|
|
/*
|
|
* Input digests for PCR extend.
|
|
* These are calculated as:
|
|
* SHA1("|Developer_Mode||Recovery_Mode||Keyblock_Mode|").
|
|
* Developer_Mode can be 0 or 1.
|
|
* Recovery_Mode can be 0 or 1.
|
|
* Keyblock flags are defined in vboot_struct.h
|
|
*
|
|
* We map them to Keyblock_Mode as follows:
|
|
* -----------------------------------------
|
|
* Keyblock Flags | Keyblock Mode
|
|
* -----------------------------------------
|
|
* 6 (Dev-signed firmware) | 2
|
|
* 7 Normal-signed firmware | 1
|
|
* (anything else) | 0
|
|
*/
|
|
|
|
const char* kBootStateSHA1Digests[] = {
|
|
/* SHA1("\x00\x00\x00") */
|
|
"\x29\xe2\xdc\xfb\xb1\x6f\x63\xbb\x02\x54\xdf\x75\x85\xa1\x5b\xb6"
|
|
"\xfb\x5e\x92\x7d",
|
|
|
|
/* SHA1("\x00\x00\x01") */
|
|
"\x25\x47\xcc\x73\x6e\x95\x1f\xa4\x91\x98\x53\xc4\x3a\xe8\x90\x86"
|
|
"\x1a\x3b\x32\x64",
|
|
|
|
/* SHA1("\x00\x00\x02") */
|
|
"\x1e\xf6\x24\x48\x2d\x62\x0e\x43\xe6\xd3\x4d\xa1\xaf\xe4\x62\x67"
|
|
"\xfc\x69\x5d\x9b",
|
|
|
|
/* SHA1("\x00\x01\x00") */
|
|
"\x62\x57\x18\x91\x21\x5b\x4e\xfc\x1c\xea\xb7\x44\xce\x59\xdd\x0b"
|
|
"\x66\xea\x6f\x73",
|
|
|
|
/* SHA1("\x00\x01\x01") */
|
|
"\xee\xe4\x47\xed\xc7\x9f\xea\x1c\xa7\xc7\xd3\x4e\x46\x32\x61\xcd"
|
|
"\xa4\xba\x33\x9e",
|
|
|
|
/* SHA1("\x00\x01\x02") */
|
|
"\x0c\x7a\x62\x3f\xd2\xbb\xc0\x5b\x06\x42\x3b\xe3\x59\xe4\x02\x1d"
|
|
"\x36\xe7\x21\xad",
|
|
|
|
/* SHA1("\x01\x00\x00") */
|
|
"\x95\x08\xe9\x05\x48\xb0\x44\x0a\x4a\x61\xe5\x74\x3b\x76\xc1\xe3"
|
|
"\x09\xb2\x3b\x7f",
|
|
|
|
/* SHA1("\x01\x00\x01") */
|
|
"\xc4\x2a\xc1\xc4\x6f\x1d\x4e\x21\x1c\x73\x5c\xc7\xdf\xad\x4f\xf8"
|
|
"\x39\x11\x10\xe9",
|
|
|
|
/* SHA1("\x01\x00\x02") */
|
|
"\xfa\x01\x0d\x26\x64\xcc\x5b\x3b\x82\xee\x48\x8f\xe2\xb9\xf5\x0f"
|
|
"\x49\x32\xeb\x8f",
|
|
|
|
/* SHA1("\x01\x01\x00") */
|
|
"\x47\xec\x8d\x98\x36\x64\x33\xdc\x00\x2e\x77\x21\xc9\xe3\x7d\x50"
|
|
"\x67\x54\x79\x37",
|
|
|
|
/* SHA1("\x01\x01\x01") */
|
|
"\x28\xd8\x6c\x56\xb3\xbf\x26\xd2\x36\x56\x9b\x8d\xc8\xc3\xf9\x1f"
|
|
"\x32\xf4\x7b\xc7",
|
|
|
|
/* SHA1("\x01\x01\x02") */
|
|
"\x12\xa3\x40\xd7\x89\x7f\xe7\x13\xfc\x8f\x02\xac\x53\x65\xb8\x6e"
|
|
"\xbf\x35\x31\x78",
|
|
};
|
|
|
|
#define MAX_BOOT_STATE_INDEX (sizeof(kBootStateSHA1Digests)/sizeof(char *))
|
|
|
|
/*
|
|
* Used for PCR extend when the passed-in boot state is invalid or if there is
|
|
* an internal error.
|
|
*/
|
|
const uint8_t kBootInvalidSHA1Digest[] = {
|
|
"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"
|
|
"\xff\xff\xff\xff"
|
|
};
|
|
|
|
/**
|
|
* Given the boot state, return the correct SHA1 digest index for TPMExtend
|
|
* in kBootStateSHA1Digests[].
|
|
*/
|
|
static int GetBootStateIndex(int dev_mode, int rec_mode,
|
|
uint64_t keyblock_flags)
|
|
{
|
|
int index = 0;
|
|
|
|
/*
|
|
* Convert keyblock flags into keyblock mode which we use to index into
|
|
* kBootStateSHA1Digest[].
|
|
*/
|
|
switch(keyblock_flags) {
|
|
case 6:
|
|
/*
|
|
* KEY_BLOCK_FLAG_RECOVERY_0 | KEY_BLOCK_FLAG_DEVELOPER_1
|
|
*
|
|
* Developer firmware. */
|
|
index = 2;
|
|
break;
|
|
case 7:
|
|
/*
|
|
* KEY_BLOCK_FLAG_RECOVERY_0 | KEY_BLOCK_FLAG_DEVELOPER_0
|
|
* | KEY_BLOCK_FLAGS_DEVELOPER_1
|
|
*/
|
|
index = 1;
|
|
break;
|
|
default:
|
|
/* Any other keyblock flags. */
|
|
index = 0;
|
|
};
|
|
|
|
if (rec_mode)
|
|
index += 3;
|
|
if (dev_mode)
|
|
index += 6;
|
|
return index;
|
|
}
|
|
|
|
uint32_t SetTPMBootModeState(int developer_mode, int recovery_mode,
|
|
uint64_t fw_keyblock_flags,
|
|
GoogleBinaryBlockHeader *gbb)
|
|
{
|
|
uint32_t result0, result1 = 0;
|
|
const uint8_t *in_digest = NULL;
|
|
uint8_t out_digest[20]; /* For PCR extend output. */
|
|
int digest_index = GetBootStateIndex(developer_mode, recovery_mode,
|
|
fw_keyblock_flags);
|
|
|
|
if (digest_index >= 0 && digest_index < MAX_BOOT_STATE_INDEX) {
|
|
in_digest = (const uint8_t*)
|
|
kBootStateSHA1Digests[digest_index];
|
|
} else {
|
|
/* Internal out of bounds error. */
|
|
in_digest = kBootInvalidSHA1Digest;
|
|
}
|
|
|
|
result0 = TlclExtend(BOOT_MODE_PCR, in_digest, out_digest);
|
|
VBDEBUG(("TPM: SetTPMBootModeState boot mode PCR%d result %d\n",
|
|
BOOT_MODE_PCR, result0));
|
|
|
|
/* Extend the HWID Digest into PCR1 (GBB v1.2 and later only) */
|
|
if (gbb && gbb->minor_version >= 2) {
|
|
result1 = TlclExtend(HWID_DIGEST_PCR, gbb->hwid_digest,
|
|
out_digest);
|
|
VBDEBUG(("TPM: SetTPMBootModeState HWID PCR%d result %d\n",
|
|
HWID_DIGEST_PCR, result1));
|
|
}
|
|
|
|
/* The caller only looks for nonzero results, not error codes. */
|
|
return result0 || result1;
|
|
}
|