diff options
author | Gaurav Shah <gauravsh@chromium.org> | 2011-03-15 16:36:29 -0700 |
---|---|---|
committer | Gaurav Shah <gauravsh@chromium.org> | 2011-03-15 16:36:29 -0700 |
commit | b64faaa7f4167344765eb32baebb0aa01a03bc29 (patch) | |
tree | 22831f297ab859e0a4c31500fb0685f6933cf74b | |
parent | 55db6a67176a4933427d2ee556180f6e814f60d9 (diff) | |
download | vboot-b64faaa7f4167344765eb32baebb0aa01a03bc29.tar.gz |
Update PCR state with the state of the firmware keyblock flags too.
I re-factored the extend call into its own module, since it doesn't necessarily
need to be couple with rollbackfirmwaresetup.
BUG=chrome-os-partner:2372
TEST=Tried emerge-x86-generic and emerge-arm-generic vboot_reference.
Change-Id: I0d3115b10b686133e63e304570325ebdbd50ae3a
Review URL: http://codereview.chromium.org/6696006
-rw-r--r-- | firmware/Makefile | 1 | ||||
-rw-r--r-- | firmware/include/tlcl.h | 2 | ||||
-rw-r--r-- | firmware/lib/include/tpm_bootmode.h | 25 | ||||
-rw-r--r-- | firmware/lib/rollback_index.c | 42 | ||||
-rw-r--r-- | firmware/lib/tpm_bootmode.c | 133 | ||||
-rw-r--r-- | firmware/lib/tpm_lite/tlcl.c | 3 | ||||
-rw-r--r-- | firmware/lib/vboot_firmware.c | 18 | ||||
-rw-r--r-- | firmware/linktest/main.c | 4 |
8 files changed, 190 insertions, 38 deletions
diff --git a/firmware/Makefile b/firmware/Makefile index fcff8bb7..b3a198b5 100644 --- a/firmware/Makefile +++ b/firmware/Makefile @@ -40,6 +40,7 @@ LIB_SRCS = \ ./lib/cryptolib/sha2.c \ ./lib/cryptolib/sha_utility.c \ ./lib/rollback_index.c \ + ./lib/tpm_bootmode.c \ ./lib/stateful_util.c \ ./lib/tpm_lite/tlcl.c \ ./lib/utility.c \ diff --git a/firmware/include/tlcl.h b/firmware/include/tlcl.h index 95310541..8e2af2c6 100644 --- a/firmware/include/tlcl.h +++ b/firmware/include/tlcl.h @@ -127,7 +127,7 @@ uint32_t TlclSetGlobalLock(void); /* Performs a TPM_Extend. */ -uint32_t TlclExtend(int pcr_num, uint8_t* in_digest, uint8_t* out_digest); +uint32_t TlclExtend(int pcr_num, const uint8_t* in_digest, uint8_t* out_digest); /* Gets the permission bits for the NVRAM space with |index|. */ diff --git a/firmware/lib/include/tpm_bootmode.h b/firmware/lib/include/tpm_bootmode.h new file mode 100644 index 00000000..6213cfe7 --- /dev/null +++ b/firmware/lib/include/tpm_bootmode.h @@ -0,0 +1,25 @@ +/* Copyright (c) 2011 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. + */ + +#ifndef VBOOT_REFERENCE_TPM_BOOTMODE_H_ +#define VBOOT_REFERENCE_TPM_BOOTMODE_H_ + +#include "sysincludes.h" + +/* Update TPM PCR State with the boot path status. + * [developer_mode]: State of the developer switch. + * [recovery_mode}: State of the recovery mode. + * [fw_keyblock_flags]: Keyblock flags on the to-be-booted + * RW firmware keyblock. + * + * Returns: TPM_SUCCESS if the TPM extend operation succeeds. + */ + +uint32_t SetTPMBootModeState(int developer_mode, int recovery_mode, + int fw_keyblock_flags); + +#endif /* VBOOT_REFERENCE_TPM_BOOTMODE_H_ */ diff --git a/firmware/lib/rollback_index.c b/firmware/lib/rollback_index.c index 0d9dc8c7..1d532f88 100644 --- a/firmware/lib/rollback_index.c +++ b/firmware/lib/rollback_index.c @@ -9,28 +9,10 @@ #include "rollback_index.h" #include "tlcl.h" +#include "tpm_bootmode.h" #include "tss_constants.h" #include "utility.h" -/* TPM PCR to use for storing dev mode measurements */ -#define DEV_REC_MODE_PCR 0 -/* Input digests for PCR extend */ -#define DEV_OFF_REC_OFF_SHA1_DIGEST ((uint8_t*) "\x14\x89\xf9\x23\xc4\xdc\xa7" \ - "\x29\x17\x8b\x3e\x32\x33\x45\x85\x50" \ - "\xd8\xdd\xdf\x29") /* SHA1("\x00\x00") */ - -#define DEV_OFF_REC_ON_SHA1_DIGEST ((uint8_t*) "\x3f\x29\x54\x64\x53\x67\x8b" \ - "\x85\x59\x31\xc1\x74\xa9\x7d\x6c\x08" \ - "\x94\xb8\xf5\x46") /* SHA1("\x00\x01") */ - -#define DEV_ON_REC_OFF_SHA1_DIGEST ((uint8_t*) "\x0e\x35\x6b\xa5\x05\x63\x1f" \ - "\xbf\x71\x57\x58\xbe\xd2\x7d\x50\x3f" \ - "\x8b\x26\x0e\x3a") /* SHA1("\x01\x00") */ - -#define DEV_ON_REC_ON_SHA1_DIGEST ((uint8_t*) "\x91\x59\xcb\x8b\xce\xe7\xfc" \ - "\xb9\x55\x82\xf1\x40\x96\x0c\xda\xe7" \ - "\x27\x88\xd3\x26") /* SHA1("\x01\x01") */ - static int g_rollback_recovery_mode = 0; /* disable MSVC warning on const logical expression (as in } while(0);) */ @@ -294,7 +276,6 @@ uint32_t RollbackFirmwareSetup(int developer_mode, uint32_t* version) { TlclStartup(); TlclContinueSelfTest(); #endif - *version = 0; return TPM_SUCCESS; } @@ -348,23 +329,14 @@ uint32_t RollbackS3Resume(void) { uint32_t RollbackFirmwareSetup(int developer_mode, uint32_t* version) { RollbackSpaceFirmware rsf; - uint8_t out_digest[20]; /* For PCR extend output */ RETURN_ON_FAILURE(SetupTPM(0, developer_mode, &rsf)); *version = rsf.fw_versions; VBDEBUG(("TPM: RollbackFirmwareSetup %x\n", (int)rsf.fw_versions)); - if (developer_mode) - RETURN_ON_FAILURE(TlclExtend(DEV_REC_MODE_PCR, DEV_ON_REC_OFF_SHA1_DIGEST, - out_digest)); - else - RETURN_ON_FAILURE(TlclExtend(DEV_REC_MODE_PCR, DEV_OFF_REC_OFF_SHA1_DIGEST, - out_digest)); - VBDEBUG(("TPM: RollbackFirmwareSetup dev mode PCR out_digest %02x %02x %02x " - "%02x\n", out_digest, out_digest+1, out_digest+2, out_digest+3)); - return TPM_SUCCESS; } + uint32_t RollbackFirmwareWrite(uint32_t version) { RollbackSpaceFirmware rsf; @@ -390,12 +362,10 @@ uint32_t RollbackKernelRecovery(int developer_mode) { * kernel will fix the TPM (if needed) and lock it ASAP. We leave * Physical Presence on in either case. */ rvs = SetupTPM(1, developer_mode, &rsf); - if (developer_mode) - rve = TlclExtend(DEV_REC_MODE_PCR, DEV_ON_REC_ON_SHA1_DIGEST, out_digest); - else - rve = TlclExtend(DEV_REC_MODE_PCR, DEV_OFF_REC_ON_SHA1_DIGEST, out_digest); - VBDEBUG(("TPM: RollbackKernelRecovery dev mode PCR out_digest %02x %02x %02x " - "%02x\n", out_digest, out_digest+1, out_digest+2, out_digest+3)); + rve = SetTPMBootModeState(developer_mode, + 1, /* Recovery Mode Status. */ + 0); /* In recovery mode, there is no RW firmware + * keyblock flag. */ return (TPM_SUCCESS == rvs) ? rve : rvs; } diff --git a/firmware/lib/tpm_bootmode.c b/firmware/lib/tpm_bootmode.c new file mode 100644 index 00000000..77731355 --- /dev/null +++ b/firmware/lib/tpm_bootmode.c @@ -0,0 +1,133 @@ +/* Copyright (c) 2011 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 "tpm_bootmode.h" + +#include "tlcl.h" +#include "utility.h" + +/* TPM PCR to use for storing boot mode measurements. */ +#define BOOT_MODE_PCR 0 + +/* 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 uint8_t kBootStateSHA1Digests[][20] = { + /* 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[20])) + +/* Used for PCR extend when the passed-in boot state is invalid or + * if there is an internal error. */ +const uint8_t kBootInvalidSHA1Digest[20] = { + "\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[]. */ +int GetBootStateIndex(int dev_mode, int rec_mode, int 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: + index = 0; /* Any other keyblock flags. */ + }; + + if (rec_mode) + index += 3; + if (dev_mode) + index += 6; + return index; +} + +uint32_t SetTPMBootModeState(int developer_mode, int recovery_mode, + int fw_keyblock_flags) { + uint32_t result; + 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 = kBootStateSHA1Digests[digest_index]; + else + in_digest = kBootInvalidSHA1Digest; /* Internal out of bounds error. */ + result = TlclExtend(BOOT_MODE_PCR, in_digest, out_digest); + VBDEBUG(("TPM: SetTPMBootModeState boot mode PCR out_digest %02x %02x %02x " + "%02x\n", out_digest, out_digest+1, out_digest+2, out_digest+3)); + return result; +} diff --git a/firmware/lib/tpm_lite/tlcl.c b/firmware/lib/tpm_lite/tlcl.c index 12742d8e..a3af5b5a 100644 --- a/firmware/lib/tpm_lite/tlcl.c +++ b/firmware/lib/tpm_lite/tlcl.c @@ -291,7 +291,8 @@ uint32_t TlclSetGlobalLock(void) { return TlclWrite(TPM_NV_INDEX0, (uint8_t*) &x, 0); } -uint32_t TlclExtend(int pcr_num, uint8_t* in_digest, uint8_t* out_digest) { +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; diff --git a/firmware/lib/vboot_firmware.c b/firmware/lib/vboot_firmware.c index bfe91866..95db892c 100644 --- a/firmware/lib/vboot_firmware.c +++ b/firmware/lib/vboot_firmware.c @@ -9,6 +9,7 @@ #include "gbb_header.h" #include "load_firmware_fw.h" #include "rollback_index.h" +#include "tpm_bootmode.h" #include "utility.h" #include "vboot_common.h" #include "vboot_nvstorage.h" @@ -53,6 +54,7 @@ int LoadFirmware(LoadFirmwareParams* params) { uint32_t status; uint32_t test_err = 0; int good_index = -1; + int boot_fw_keyblock_flags = 0; int is_dev; int index; int i; @@ -274,6 +276,9 @@ int LoadFirmware(LoadFirmwareParams* params) { * this firmware. That's the one we'll boot. */ good_index = index; params->firmware_index = index; + /* Since we now know which firmware to boot, we can update the + * bootable firmware key block mode. */ + boot_fw_keyblock_flags = key_block->key_block_flags; /* If the good firmware's key version is the same as the tpm, * then the TPM doesn't need updating; we can stop now. @@ -284,6 +289,19 @@ int LoadFirmware(LoadFirmwareParams* params) { } } + /* At this point, we have a good idea of how we are going to boot. Update the + * TPM with this state information. + */ + status = SetTPMBootModeState(is_dev, 0, boot_fw_keyblock_flags); + if (0 != status) { + VBDEBUG(("Unable to update the TPM with boot mode information.\n")); + if (status == TPM_E_MUST_REBOOT) + retval = LOAD_FIRMWARE_REBOOT; + else + recovery = VBNV_RECOVERY_RO_TPM_ERROR; + goto LoadFirmwareExit; + } + /* Free internal data */ Free(lfi); params->load_firmware_internal = NULL; diff --git a/firmware/linktest/main.c b/firmware/linktest/main.c index 6f5b83e4..16c4bf50 100644 --- a/firmware/linktest/main.c +++ b/firmware/linktest/main.c @@ -8,6 +8,7 @@ #include "load_kernel_fw.h" #include "rollback_index.h" #include "tlcl.h" +#include "tpm_bootmode.h" #include "vboot_common.h" #include "vboot_kernel.h" #include "vboot_nvstorage.h" @@ -37,6 +38,9 @@ int main(void) RollbackKernelWrite(0); RollbackKernelLock(); + /* tpm_bootmode.c */ + SetTPMBootModeState(0, 0, 0); + /* tlcl.h */ TlclLibInit(); TlclCloseDevice(); |