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security/vboot: extract secdata_tpm{1,2}.c

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Most of the original secdata_tpm.c was TPM2-specific implementation.

Just moving the code around, with trivial tweaks:
 - drop now unnecessary #ifdef directives from _factory_initialize_tpm()
 - drop leading underscore from _factory_initialize_tpm{1,2}() (external
   identifiers should not start with an underscore in C)
 - drop unused <security/vboot/tpm_common.h> include and sub-includes of
   tss.h which should be considered its part (so this isn't an indirect
   inclusion)
 - fixed formatting of RETURN_ON_FAILURE() which didn't have slashes
   aligned no matter what tab width was used

Change-Id: I0090b748d7d3b2d76a941b87b5885682fd81c4fc
Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/81415
Reviewed-by: Julius Werner <jwerner@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
This commit is contained in:
Sergii Dmytruk
2024-03-21 21:06:49 +02:00
committed by Martin L Roth
parent 47e9e8cde1
commit efc615e239
5 changed files with 572 additions and 549 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
src/security/vboot/Makefile.mk
View File

@@ -118,6 +118,14 @@ else
verstage-y += secdata_tpm.c
romstage-y += secdata_tpm.c
ramstage-y += secdata_tpm.c
verstage-$(CONFIG_TPM1) += secdata_tpm1.c
romstage-$(CONFIG_TPM1) += secdata_tpm1.c
ramstage-$(CONFIG_TPM1) += secdata_tpm1.c
verstage-$(CONFIG_TPM2) += secdata_tpm2.c
romstage-$(CONFIG_TPM2) += secdata_tpm2.c
ramstage-$(CONFIG_TPM2) += secdata_tpm2.c
endif
verstage-$(CONFIG_TPM) += tpm_common.c

556
src/security/vboot/secdata_tpm.c
View File

@@ -5,28 +5,12 @@
* stored in the TPM NVRAM.
*/
#include <security/vboot/antirollback.h>
#include <security/vboot/tpm_common.h>
#include <security/tpm/tspi.h>
#include <security/tpm/tss.h>
#include <security/tpm/tss/tcg-1.2/tss_structures.h>
#include <security/tpm/tss/tcg-2.0/tss_structures.h>
#include <vb2_api.h>
#include <console/console.h>
#include <security/tpm/tspi.h>
#include <security/vboot/antirollback.h>
#include <vb2_api.h>
#define VBDEBUG(format, args...) \
printk(BIOS_INFO, "%s():%d: " format, __func__, __LINE__, ## args)
#define RETURN_ON_FAILURE(tpm_cmd) do { \
tpm_result_t rc_; \
if ((rc_ = (tpm_cmd)) != TPM_SUCCESS) { \
VBDEBUG("Antirollback: %08x returned by " #tpm_cmd \
"\n", (tpm_result_t)rc_); \
return rc_; \
} \
} while (0)
static tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length);
#include "secdata_tpm_private.h"
tpm_result_t antirollback_read_space_kernel(struct vb2_context *ctx)
{
@@ -69,529 +53,7 @@ tpm_result_t antirollback_read_space_kernel(struct vb2_context *ctx)
return TPM_SUCCESS;
}
#if CONFIG(TPM2)
static tpm_result_t read_space_mrc_hash(uint32_t index, uint8_t *data)
{
RETURN_ON_FAILURE(tlcl_read(index, data,
HASH_NV_SIZE));
return TPM_SUCCESS;
}
/*
* This is used to initialize the TPM space for recovery hash after defining
* it. Since there is no data available to calculate hash at the point where TPM
* space is defined, initialize it to all 0s.
*/
static const uint8_t mrc_hash_data[HASH_NV_SIZE] = { };
/*
* Different sets of NVRAM space attributes apply to the "ro" spaces,
* i.e. those which should not be possible to delete or modify once
* the RO exits, and the rest of the NVRAM spaces.
*/
static const TPMA_NV ro_space_attributes = {
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV rw_space_attributes = {
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
};
static const TPMA_NV rw_auth_space_attributes = {
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_NO_DA = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV fwmp_attr = {
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_OWNERWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PPWRITE = 1,
};
/* Attributes for spaces that enable zero-touch enrollment (ZTE) */
static const TPMA_NV zte_attr = {
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITEDEFINE = 1,
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_NO_DA = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV zte_rma_bytes_attr = {
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_BITS = 1,
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_NO_DA = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV rw_orderly_counter_attributes = {
.TPMA_NV_COUNTER = 1,
.TPMA_NV_ORDERLY = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_NO_DA = 1,
};
/*
* This policy digest was obtained using TPM2_PolicyOR on 3 digests
* corresponding to a sequence of
* -) TPM2_PolicyCommandCode(TPM_CC_NV_UndefineSpaceSpecial),
* -) TPM2_PolicyPCR(PCR0, <extended_value>).
* where <extended value> is
* 1) all zeros = initial, unextended state:
* - Value to extend to initial PCR0:
* <none>
* - Resulting PCR0:
* 0000000000000000000000000000000000000000000000000000000000000000
* - Policy digest for PolicyCommandCode + PolicyPCR:
* 4B44FC4192DB5AD7167E0135708FD374890A06BFB56317DF01F24F2226542A3F
* 2) result of extending (SHA1(0x00|0x01|0x00) | 00s to SHA256 size)
* - Value to extend to initial PCR0:
* 62571891215b4efc1ceab744ce59dd0b66ea6f73000000000000000000000000
* - Resulting PCR0:
* 9F9EA866D3F34FE3A3112AE9CB1FBABC6FFE8CD261D42493BC6842A9E4F93B3D
* - Policy digest for PolicyCommandCode + PolicyPCR:
* CB5C8014E27A5F7586AAE42DB4F9776A977BCBC952CA61E33609DA2B2C329418
* 3) result of extending (SHA1(0x01|0x01|0x00) | 00s to SHA256 size)
* - Value to extend to initial PCR0:
* 47ec8d98366433dc002e7721c9e37d5067547937000000000000000000000000
* - Resulting PCR0:
* 2A7580E5DA289546F4D2E0509CC6DE155EA131818954D36D49E027FD42B8C8F8
* - Policy digest for PolicyCommandCode + PolicyPCR:
* E6EF4F0296AC3EF0F53906480985B1BE8058E0E517E5F74A5B8A415EFE339D87
* Values #2 and #3 correspond to two forms of recovery mode as extended by
* vb2api_get_pcr_digest().
* As a result, the digest allows deleting the space with UndefineSpaceSpecial
* at early RO stages (before extending PCR0) or from recovery mode.
*/
static const uint8_t pcr0_allowed_policy[] = {
0x44, 0x44, 0x79, 0x00, 0xCB, 0xB8, 0x3F, 0x5B, 0x15, 0x76, 0x56,
0x50, 0xEF, 0x96, 0x98, 0x0A, 0x2B, 0x96, 0x6E, 0xA9, 0x09, 0x04,
0x4A, 0x01, 0xB8, 0x5F, 0xA5, 0x4A, 0x96, 0xFC, 0x59, 0x84};
static const uint8_t unsatisfiable_policy[VB2_SHA256_DIGEST_SIZE] =
"hmwhat if RBR beat merc in 2021";
static uint32_t define_space(const char *name, uint32_t index, uint32_t length,
const TPMA_NV nv_attributes,
const uint8_t *nv_policy, size_t nv_policy_size)
{
tpm_result_t rc;
rc = tlcl2_define_space(index, length, nv_attributes, nv_policy, nv_policy_size);
if (rc == TPM_CB_NV_DEFINED) {
/*
* Continue with writing: it may be defined, but not written
* to. In that case a subsequent tlcl_read() would still return
* TPM_BADINDEX on TPM 2.0. The cases when some non-firmware
* space is defined while the firmware space is not there
* should be rare (interrupted initialization), so no big harm
* in writing once again even if it was written already.
*/
VBDEBUG("%s: %s space already exists\n", __func__, name);
rc = TPM_SUCCESS;
}
return rc;
}
static tpm_result_t setup_space(const char *name, uint32_t index, const void *data,
uint32_t length, const TPMA_NV nv_attributes,
const uint8_t *nv_policy, size_t nv_policy_size)
{
tpm_result_t rc;
rc = define_space(name, index, length, nv_attributes, nv_policy,
nv_policy_size);
if (rc != TPM_SUCCESS)
return rc;
return safe_write(index, data, length);
}
static tpm_result_t setup_firmware_space(struct vb2_context *ctx)
{
uint32_t firmware_space_size = vb2api_secdata_firmware_create(ctx);
return setup_space("firmware", FIRMWARE_NV_INDEX,
ctx->secdata_firmware, firmware_space_size,
ro_space_attributes, pcr0_allowed_policy,
sizeof(pcr0_allowed_policy));
}
static tpm_result_t setup_fwmp_space(struct vb2_context *ctx)
{
uint32_t fwmp_space_size = vb2api_secdata_fwmp_create(ctx);
return setup_space("FWMP", FWMP_NV_INDEX, ctx->secdata_fwmp, fwmp_space_size,
fwmp_attr, NULL, 0);
}
static tpm_result_t setup_kernel_space(struct vb2_context *ctx)
{
uint32_t kernel_space_size = vb2api_secdata_kernel_create(ctx);
return setup_space("kernel", KERNEL_NV_INDEX, ctx->secdata_kernel,
kernel_space_size, rw_space_attributes, NULL, 0);
}
static tpm_result_t set_mrc_hash_space(uint32_t index, const uint8_t *data)
{
if (index == MRC_REC_HASH_NV_INDEX) {
return setup_space("RO MRC Hash", index, data, HASH_NV_SIZE,
ro_space_attributes, pcr0_allowed_policy,
sizeof(pcr0_allowed_policy));
} else {
return setup_space("RW MRC Hash", index, data, HASH_NV_SIZE,
rw_space_attributes, NULL, 0);
}
}
/**
* Set up the Zero-Touch Enrollment(ZTE) related spaces.
*
* These spaces are not used by firmware, but we do need to initialize them.
*/
static tpm_result_t setup_zte_spaces(void)
{
tpm_result_t rc;
uint64_t rma_bytes_counter_default = 0;
uint8_t rma_sn_bits_default[16];
uint8_t board_id_default[12];
/* Initialize defaults: Board ID and RMA+SN Bits must be initialized
to all 0xFFs. */
memset(rma_sn_bits_default, 0xFF, ARRAY_SIZE(rma_sn_bits_default));
memset(board_id_default, 0xFF, ARRAY_SIZE(board_id_default));
/* Set up RMA + SN Bits */
rc = setup_space("RMA + SN Bits", ZTE_RMA_SN_BITS_INDEX,
rma_sn_bits_default, sizeof(rma_sn_bits_default),
zte_attr,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to set up RMA + SN Bits space with error %#x\n", __func__, rc);
return rc;
}
rc = setup_space("Board ID", ZTE_BOARD_ID_NV_INDEX,
board_id_default, sizeof(board_id_default),
zte_attr,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to set up Board ID space with error %#x\n", __func__, rc);
return rc;
}
/* Set up RMA Bytes counter */
rc = define_space("RMA Bytes Counter", ZTE_RMA_BYTES_COUNTER_INDEX,
sizeof(rma_bytes_counter_default),
zte_rma_bytes_attr,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to define RMA Bytes space with error %#x\n", __func__, rc);
return rc;
}
/*
* Since the RMA counter has the BITS attribute, we need to call
* TPM2_NV_SetBits() in order to initialize it.
*/
rc = tlcl2_set_bits(ZTE_RMA_BYTES_COUNTER_INDEX, rma_bytes_counter_default);
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to init RMA Bytes counter space wit error %#x\n",
__func__, rc);
return rc;
}
return rc;
}
/*
* Set up enterprise rollback space.
*
* This space is not used by firmware but needs to survive owner clear. Thus, it
* needs to be created here.
*/
static tpm_result_t enterprise_rollback_create_space(void)
{
uint8_t rollback_space_default[32] = {0};
return setup_space("Enterprise Rollback Space",
ENT_ROLLBACK_SPACE_INDEX, rollback_space_default,
sizeof(rollback_space_default), rw_auth_space_attributes,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
}
static tpm_result_t setup_widevine_counter_spaces(void)
{
uint32_t index;
tpm_result_t rc;
for (index = 0; index < NUM_WIDEVINE_COUNTERS; index++) {
rc = define_space(WIDEVINE_COUNTER_NAME,
WIDEVINE_COUNTER_NV_INDEX(index),
WIDEVINE_COUNTER_SIZE,
rw_orderly_counter_attributes,
NULL,
0);
if (rc != TPM_SUCCESS)
return rc;
}
return rc;
}
static tpm_result_t _factory_initialize_tpm2(struct vb2_context *ctx)
{
RETURN_ON_FAILURE(tlcl_force_clear());
/*
* Of all NVRAM spaces defined by this function the firmware space
* must be defined last, because its existence is considered an
* indication that TPM factory initialization was successfully
* completed.
*/
RETURN_ON_FAILURE(setup_kernel_space(ctx));
/*
* Define and set rec hash space, if available. No need to
* create the RW hash space because we will definitely boot
* once in normal mode before shipping, meaning that the space
* will get created with correct permissions while still in
* our hands.
*/
if (CONFIG(VBOOT_HAS_REC_HASH_SPACE))
RETURN_ON_FAILURE(set_mrc_hash_space(MRC_REC_HASH_NV_INDEX, mrc_hash_data));
/* Define and write firmware management parameters space. */
RETURN_ON_FAILURE(setup_fwmp_space(ctx));
/*
* Define and write zero-touch enrollment (ZTE) spaces. For ChromeOS devices with
* Google TPM, these are set up elsewhere via TPM vendor commands.
*/
if (CONFIG(CHROMEOS) && !(CONFIG(TPM_GOOGLE)))
RETURN_ON_FAILURE(setup_zte_spaces());
/*
* On TPM 2.0, create a space that survives TPM clear. This allows to
* securely lock data during enterprise rollback by binding to this
* space's value.
*/
if (CONFIG(CHROMEOS))
RETURN_ON_FAILURE(enterprise_rollback_create_space());
/* Define widevine counter space. No need to increment/write to the secure counters
and are expected to be incremented during the first use. */
if (CONFIG(VBOOT_DEFINE_WIDEVINE_COUNTERS))
RETURN_ON_FAILURE(setup_widevine_counter_spaces());
RETURN_ON_FAILURE(setup_firmware_space(ctx));
return TPM_SUCCESS;
}
tpm_result_t antirollback_read_space_mrc_hash(uint32_t index, uint8_t *data, uint32_t size)
{
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", index, HASH_NV_SIZE,
size);
return TPM_CB_READ_FAILURE;
}
return read_space_mrc_hash(index, data);
}
tpm_result_t antirollback_write_space_mrc_hash(uint32_t index, const uint8_t *data, uint32_t size)
{
uint8_t spc_data[HASH_NV_SIZE];
tpm_result_t rc;
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", index, HASH_NV_SIZE,
size);
return TPM_CB_WRITE_FAILURE;
}
rc = read_space_mrc_hash(index, spc_data);
if (rc == TPM_BADINDEX) {
/*
* If space is not defined already for hash, define
* new space.
*/
VBDEBUG("TPM: Initializing hash space.\n");
return set_mrc_hash_space(index, data);
}
if (rc != TPM_SUCCESS)
return rc;
return safe_write(index, data, size);
}
tpm_result_t antirollback_lock_space_mrc_hash(uint32_t index)
{
return tlcl2_lock_nv_write(index);
}
static tpm_result_t read_space_vbios_hash(uint8_t *data)
{
RETURN_ON_FAILURE(tlcl_read(VBIOS_CACHE_NV_INDEX, data, HASH_NV_SIZE));
return TPM_SUCCESS;
}
tpm_result_t antirollback_read_space_vbios_hash(uint8_t *data, uint32_t size)
{
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", VBIOS_CACHE_NV_INDEX, HASH_NV_SIZE,
size);
return TPM_CB_READ_FAILURE;
}
return read_space_vbios_hash(data);
}
tpm_result_t antirollback_write_space_vbios_hash(const uint8_t *data, uint32_t size)
{
uint8_t spc_data[HASH_NV_SIZE];
tpm_result_t rc;
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", VBIOS_CACHE_NV_INDEX, HASH_NV_SIZE,
size);
return TPM_CB_WRITE_FAILURE;
}
rc = read_space_vbios_hash(spc_data);
if (rc == TPM_BADINDEX) {
/*
* If space is not defined already for hash, define
* new space.
*/
VBDEBUG("TPM: Initializing hash space.\n");
return setup_space("VBIOS Cache Hash", VBIOS_CACHE_NV_INDEX, data, HASH_NV_SIZE,
rw_space_attributes, NULL, 0);
}
if (rc != TPM_SUCCESS)
return rc;
return safe_write(VBIOS_CACHE_NV_INDEX, data, size);
}
#endif /* CONFIG(TPM2) */
#if CONFIG(TPM1)
/**
* Similarly to safe_write(), this ensures we don't fail a DefineSpace because
* we hit the TPM write limit. This is even less likely to happen than with
* writes because we only define spaces once at initialization, but we'd
* rather be paranoid about this.
*/
static tpm_result_t safe_define_space(uint32_t index, uint32_t perm, uint32_t size)
{
tpm_result_t rc = tlcl1_define_space(index, perm, size);
if (rc == TPM_MAXNVWRITES) {
RETURN_ON_FAILURE(tpm_clear_and_reenable());
return tlcl1_define_space(index, perm, size);
} else {
return rc;
}
}
static tpm_result_t _factory_initialize_tpm1(struct vb2_context *ctx)
{
TPM_PERMANENT_FLAGS pflags;
tpm_result_t rc;
vb2api_secdata_firmware_create(ctx);
vb2api_secdata_kernel_create_v0(ctx);
rc = tlcl1_get_permanent_flags(&pflags);
if (rc != TPM_SUCCESS)
return rc;
/*
* TPM may come from the factory without physical presence finalized.
* Fix if necessary.
*/
VBDEBUG("TPM: physicalPresenceLifetimeLock=%d\n",
pflags.physicalPresenceLifetimeLock);
if (!pflags.physicalPresenceLifetimeLock) {
VBDEBUG("TPM: Finalizing physical presence\n");
RETURN_ON_FAILURE(tlcl_finalize_physical_presence());
}
/*
* The TPM will not enforce the NV authorization restrictions until the
* execution of a TPM_NV_DefineSpace with the handle of
* TPM_NV_INDEX_LOCK. Here we create that space if it doesn't already
* exist. */
VBDEBUG("TPM: nvLocked=%d\n", pflags.nvLocked);
if (!pflags.nvLocked) {
VBDEBUG("TPM: Enabling NV locking\n");
RETURN_ON_FAILURE(tlcl1_set_nv_locked());
}
/* Clear TPM owner, in case the TPM is already owned for some reason. */
VBDEBUG("TPM: Clearing owner\n");
RETURN_ON_FAILURE(tpm_clear_and_reenable());
/* Define and write secdata_kernel space. */
RETURN_ON_FAILURE(safe_define_space(KERNEL_NV_INDEX,
TPM_NV_PER_PPWRITE,
VB2_SECDATA_KERNEL_SIZE_V02));
RETURN_ON_FAILURE(safe_write(KERNEL_NV_INDEX,
ctx->secdata_kernel,
VB2_SECDATA_KERNEL_SIZE_V02));
/* Define and write secdata_firmware space. */
RETURN_ON_FAILURE(safe_define_space(FIRMWARE_NV_INDEX,
TPM_NV_PER_GLOBALLOCK |
TPM_NV_PER_PPWRITE,
VB2_SECDATA_FIRMWARE_SIZE));
RETURN_ON_FAILURE(safe_write(FIRMWARE_NV_INDEX,
ctx->secdata_firmware,
VB2_SECDATA_FIRMWARE_SIZE));
return TPM_SUCCESS;
}
#endif /* CONFIG(TPM1) */
static tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length)
tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length)
{
tpm_result_t rc = tlcl_write(index, data, length);
if (tlcl_get_family() == TPM_1 && rc == TPM_MAXNVWRITES) {
@@ -609,14 +71,10 @@ static tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length
static uint32_t _factory_initialize_tpm(struct vb2_context *ctx)
{
#if CONFIG(TPM1)
if (tlcl_get_family() == TPM_1)
return _factory_initialize_tpm1(ctx);
#endif
#if CONFIG(TPM2)
return factory_initialize_tpm1(ctx);
if (tlcl_get_family() == TPM_2)
return _factory_initialize_tpm2(ctx);
#endif
return factory_initialize_tpm2(ctx);
return TPM_CB_CORRUPTED_STATE;
}

83
src/security/vboot/secdata_tpm1.c Normal file
View File

@@ -0,0 +1,83 @@
/* SPDX-License-Identifier: BSD-3-Clause */
#include <security/tpm/tspi.h>
#include <security/tpm/tss.h>
#include <security/vboot/antirollback.h>
#include <vb2_api.h>
#include "secdata_tpm_private.h"
/**
* Similarly to safe_write(), this ensures we don't fail a DefineSpace because
* we hit the TPM write limit. This is even less likely to happen than with
* writes because we only define spaces once at initialization, but we'd
* rather be paranoid about this.
*/
static tpm_result_t safe_define_space(uint32_t index, uint32_t perm, uint32_t size)
{
tpm_result_t rc = tlcl1_define_space(index, perm, size);
if (rc == TPM_MAXNVWRITES) {
RETURN_ON_FAILURE(tpm_clear_and_reenable());
return tlcl1_define_space(index, perm, size);
} else {
return rc;
}
}
tpm_result_t factory_initialize_tpm1(struct vb2_context *ctx)
{
TPM_PERMANENT_FLAGS pflags;
tpm_result_t rc;
vb2api_secdata_firmware_create(ctx);
vb2api_secdata_kernel_create_v0(ctx);
rc = tlcl1_get_permanent_flags(&pflags);
if (rc != TPM_SUCCESS)
return rc;
/*
* TPM may come from the factory without physical presence finalized.
* Fix if necessary.
*/
VBDEBUG("TPM: physicalPresenceLifetimeLock=%d\n",
pflags.physicalPresenceLifetimeLock);
if (!pflags.physicalPresenceLifetimeLock) {
VBDEBUG("TPM: Finalizing physical presence\n");
RETURN_ON_FAILURE(tlcl_finalize_physical_presence());
}
/*
* The TPM will not enforce the NV authorization restrictions until the
* execution of a TPM_NV_DefineSpace with the handle of
* TPM_NV_INDEX_LOCK. Here we create that space if it doesn't already
* exist. */
VBDEBUG("TPM: nvLocked=%d\n", pflags.nvLocked);
if (!pflags.nvLocked) {
VBDEBUG("TPM: Enabling NV locking\n");
RETURN_ON_FAILURE(tlcl1_set_nv_locked());
}
/* Clear TPM owner, in case the TPM is already owned for some reason. */
VBDEBUG("TPM: Clearing owner\n");
RETURN_ON_FAILURE(tpm_clear_and_reenable());
/* Define and write secdata_kernel space. */
RETURN_ON_FAILURE(safe_define_space(KERNEL_NV_INDEX,
TPM_NV_PER_PPWRITE,
VB2_SECDATA_KERNEL_SIZE_V02));
RETURN_ON_FAILURE(safe_write(KERNEL_NV_INDEX,
ctx->secdata_kernel,
VB2_SECDATA_KERNEL_SIZE_V02));
/* Define and write secdata_firmware space. */
RETURN_ON_FAILURE(safe_define_space(FIRMWARE_NV_INDEX,
TPM_NV_PER_GLOBALLOCK |
TPM_NV_PER_PPWRITE,
VB2_SECDATA_FIRMWARE_SIZE));
RETURN_ON_FAILURE(safe_write(FIRMWARE_NV_INDEX,
ctx->secdata_firmware,
VB2_SECDATA_FIRMWARE_SIZE));
return TPM_SUCCESS;
}

446
src/security/vboot/secdata_tpm2.c Normal file
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/* SPDX-License-Identifier: BSD-3-Clause */
#include <security/vboot/antirollback.h>
#include <security/tpm/tss.h>
#include <vb2_api.h>
#include "secdata_tpm_private.h"
static tpm_result_t read_space_mrc_hash(uint32_t index, uint8_t *data)
{
RETURN_ON_FAILURE(tlcl_read(index, data,
HASH_NV_SIZE));
return TPM_SUCCESS;
}
/*
* This is used to initialize the TPM space for recovery hash after defining
* it. Since there is no data available to calculate hash at the point where TPM
* space is defined, initialize it to all 0s.
*/
static const uint8_t mrc_hash_data[HASH_NV_SIZE] = { };
/*
* Different sets of NVRAM space attributes apply to the "ro" spaces,
* i.e. those which should not be possible to delete or modify once
* the RO exits, and the rest of the NVRAM spaces.
*/
static const TPMA_NV ro_space_attributes = {
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV rw_space_attributes = {
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
};
static const TPMA_NV rw_auth_space_attributes = {
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_NO_DA = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV fwmp_attr = {
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_OWNERWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PPWRITE = 1,
};
/* Attributes for spaces that enable zero-touch enrollment (ZTE) */
static const TPMA_NV zte_attr = {
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITEDEFINE = 1,
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_NO_DA = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV zte_rma_bytes_attr = {
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_BITS = 1,
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_NO_DA = 1,
.TPMA_NV_POLICY_DELETE = 1,
};
static const TPMA_NV rw_orderly_counter_attributes = {
.TPMA_NV_COUNTER = 1,
.TPMA_NV_ORDERLY = 1,
.TPMA_NV_AUTHREAD = 1,
.TPMA_NV_AUTHWRITE = 1,
.TPMA_NV_PLATFORMCREATE = 1,
.TPMA_NV_WRITE_STCLEAR = 1,
.TPMA_NV_PPREAD = 1,
.TPMA_NV_PPWRITE = 1,
.TPMA_NV_NO_DA = 1,
};
/*
* This policy digest was obtained using TPM2_PolicyOR on 3 digests
* corresponding to a sequence of
* -) TPM2_PolicyCommandCode(TPM_CC_NV_UndefineSpaceSpecial),
* -) TPM2_PolicyPCR(PCR0, <extended_value>).
* where <extended value> is
* 1) all zeros = initial, unextended state:
* - Value to extend to initial PCR0:
* <none>
* - Resulting PCR0:
* 0000000000000000000000000000000000000000000000000000000000000000
* - Policy digest for PolicyCommandCode + PolicyPCR:
* 4B44FC4192DB5AD7167E0135708FD374890A06BFB56317DF01F24F2226542A3F
* 2) result of extending (SHA1(0x00|0x01|0x00) | 00s to SHA256 size)
* - Value to extend to initial PCR0:
* 62571891215b4efc1ceab744ce59dd0b66ea6f73000000000000000000000000
* - Resulting PCR0:
* 9F9EA866D3F34FE3A3112AE9CB1FBABC6FFE8CD261D42493BC6842A9E4F93B3D
* - Policy digest for PolicyCommandCode + PolicyPCR:
* CB5C8014E27A5F7586AAE42DB4F9776A977BCBC952CA61E33609DA2B2C329418
* 3) result of extending (SHA1(0x01|0x01|0x00) | 00s to SHA256 size)
* - Value to extend to initial PCR0:
* 47ec8d98366433dc002e7721c9e37d5067547937000000000000000000000000
* - Resulting PCR0:
* 2A7580E5DA289546F4D2E0509CC6DE155EA131818954D36D49E027FD42B8C8F8
* - Policy digest for PolicyCommandCode + PolicyPCR:
* E6EF4F0296AC3EF0F53906480985B1BE8058E0E517E5F74A5B8A415EFE339D87
* Values #2 and #3 correspond to two forms of recovery mode as extended by
* vb2api_get_pcr_digest().
* As a result, the digest allows deleting the space with UndefineSpaceSpecial
* at early RO stages (before extending PCR0) or from recovery mode.
*/
static const uint8_t pcr0_allowed_policy[] = {
0x44, 0x44, 0x79, 0x00, 0xCB, 0xB8, 0x3F, 0x5B, 0x15, 0x76, 0x56,
0x50, 0xEF, 0x96, 0x98, 0x0A, 0x2B, 0x96, 0x6E, 0xA9, 0x09, 0x04,
0x4A, 0x01, 0xB8, 0x5F, 0xA5, 0x4A, 0x96, 0xFC, 0x59, 0x84};
static const uint8_t unsatisfiable_policy[VB2_SHA256_DIGEST_SIZE] =
"hmwhat if RBR beat merc in 2021";
static uint32_t define_space(const char *name, uint32_t index, uint32_t length,
const TPMA_NV nv_attributes,
const uint8_t *nv_policy, size_t nv_policy_size)
{
tpm_result_t rc;
rc = tlcl2_define_space(index, length, nv_attributes, nv_policy, nv_policy_size);
if (rc == TPM_CB_NV_DEFINED) {
/*
* Continue with writing: it may be defined, but not written
* to. In that case a subsequent tlcl_read() would still return
* TPM_BADINDEX on TPM 2.0. The cases when some non-firmware
* space is defined while the firmware space is not there
* should be rare (interrupted initialization), so no big harm
* in writing once again even if it was written already.
*/
VBDEBUG("%s: %s space already exists\n", __func__, name);
rc = TPM_SUCCESS;
}
return rc;
}
static tpm_result_t setup_space(const char *name, uint32_t index, const void *data,
uint32_t length, const TPMA_NV nv_attributes,
const uint8_t *nv_policy, size_t nv_policy_size)
{
tpm_result_t rc;
rc = define_space(name, index, length, nv_attributes, nv_policy,
nv_policy_size);
if (rc != TPM_SUCCESS)
return rc;
return safe_write(index, data, length);
}
static tpm_result_t setup_firmware_space(struct vb2_context *ctx)
{
uint32_t firmware_space_size = vb2api_secdata_firmware_create(ctx);
return setup_space("firmware", FIRMWARE_NV_INDEX,
ctx->secdata_firmware, firmware_space_size,
ro_space_attributes, pcr0_allowed_policy,
sizeof(pcr0_allowed_policy));
}
static tpm_result_t setup_fwmp_space(struct vb2_context *ctx)
{
uint32_t fwmp_space_size = vb2api_secdata_fwmp_create(ctx);
return setup_space("FWMP", FWMP_NV_INDEX, ctx->secdata_fwmp, fwmp_space_size,
fwmp_attr, NULL, 0);
}
static tpm_result_t setup_kernel_space(struct vb2_context *ctx)
{
uint32_t kernel_space_size = vb2api_secdata_kernel_create(ctx);
return setup_space("kernel", KERNEL_NV_INDEX, ctx->secdata_kernel,
kernel_space_size, rw_space_attributes, NULL, 0);
}
static tpm_result_t set_mrc_hash_space(uint32_t index, const uint8_t *data)
{
if (index == MRC_REC_HASH_NV_INDEX) {
return setup_space("RO MRC Hash", index, data, HASH_NV_SIZE,
ro_space_attributes, pcr0_allowed_policy,
sizeof(pcr0_allowed_policy));
} else {
return setup_space("RW MRC Hash", index, data, HASH_NV_SIZE,
rw_space_attributes, NULL, 0);
}
}
/**
* Set up the Zero-Touch Enrollment(ZTE) related spaces.
*
* These spaces are not used by firmware, but we do need to initialize them.
*/
static tpm_result_t setup_zte_spaces(void)
{
tpm_result_t rc;
uint64_t rma_bytes_counter_default = 0;
uint8_t rma_sn_bits_default[16];
uint8_t board_id_default[12];
/* Initialize defaults: Board ID and RMA+SN Bits must be initialized
to all 0xFFs. */
memset(rma_sn_bits_default, 0xFF, ARRAY_SIZE(rma_sn_bits_default));
memset(board_id_default, 0xFF, ARRAY_SIZE(board_id_default));
/* Set up RMA + SN Bits */
rc = setup_space("RMA + SN Bits", ZTE_RMA_SN_BITS_INDEX,
rma_sn_bits_default, sizeof(rma_sn_bits_default),
zte_attr,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to set up RMA + SN Bits space with error %#x\n", __func__, rc);
return rc;
}
rc = setup_space("Board ID", ZTE_BOARD_ID_NV_INDEX,
board_id_default, sizeof(board_id_default),
zte_attr,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to set up Board ID space with error %#x\n", __func__, rc);
return rc;
}
/* Set up RMA Bytes counter */
rc = define_space("RMA Bytes Counter", ZTE_RMA_BYTES_COUNTER_INDEX,
sizeof(rma_bytes_counter_default),
zte_rma_bytes_attr,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to define RMA Bytes space with error %#x\n", __func__, rc);
return rc;
}
/*
* Since the RMA counter has the BITS attribute, we need to call
* TPM2_NV_SetBits() in order to initialize it.
*/
rc = tlcl2_set_bits(ZTE_RMA_BYTES_COUNTER_INDEX, rma_bytes_counter_default);
if (rc != TPM_SUCCESS) {
VBDEBUG("%s: Failed to init RMA Bytes counter space wit error %#x\n",
__func__, rc);
return rc;
}
return rc;
}
/*
* Set up enterprise rollback space.
*
* This space is not used by firmware but needs to survive owner clear. Thus, it
* needs to be created here.
*/
static tpm_result_t enterprise_rollback_create_space(void)
{
uint8_t rollback_space_default[32] = {0};
return setup_space("Enterprise Rollback Space",
ENT_ROLLBACK_SPACE_INDEX, rollback_space_default,
sizeof(rollback_space_default), rw_auth_space_attributes,
unsatisfiable_policy, sizeof(unsatisfiable_policy));
}
static tpm_result_t setup_widevine_counter_spaces(void)
{
uint32_t index;
tpm_result_t rc;
for (index = 0; index < NUM_WIDEVINE_COUNTERS; index++) {
rc = define_space(WIDEVINE_COUNTER_NAME,
WIDEVINE_COUNTER_NV_INDEX(index),
WIDEVINE_COUNTER_SIZE,
rw_orderly_counter_attributes,
NULL,
0);
if (rc != TPM_SUCCESS)
return rc;
}
return rc;
}
tpm_result_t factory_initialize_tpm2(struct vb2_context *ctx)
{
RETURN_ON_FAILURE(tlcl_force_clear());
/*
* Of all NVRAM spaces defined by this function the firmware space
* must be defined last, because its existence is considered an
* indication that TPM factory initialization was successfully
* completed.
*/
RETURN_ON_FAILURE(setup_kernel_space(ctx));
/*
* Define and set rec hash space, if available. No need to
* create the RW hash space because we will definitely boot
* once in normal mode before shipping, meaning that the space
* will get created with correct permissions while still in
* our hands.
*/
if (CONFIG(VBOOT_HAS_REC_HASH_SPACE))
RETURN_ON_FAILURE(set_mrc_hash_space(MRC_REC_HASH_NV_INDEX, mrc_hash_data));
/* Define and write firmware management parameters space. */
RETURN_ON_FAILURE(setup_fwmp_space(ctx));
/*
* Define and write zero-touch enrollment (ZTE) spaces. For ChromeOS devices with
* Google TPM, these are set up elsewhere via TPM vendor commands.
*/
if (CONFIG(CHROMEOS) && !(CONFIG(TPM_GOOGLE)))
RETURN_ON_FAILURE(setup_zte_spaces());
/*
* On TPM 2.0, create a space that survives TPM clear. This allows to
* securely lock data during enterprise rollback by binding to this
* space's value.
*/
if (CONFIG(CHROMEOS))
RETURN_ON_FAILURE(enterprise_rollback_create_space());
/* Define widevine counter space. No need to increment/write to the secure counters
and are expected to be incremented during the first use. */
if (CONFIG(VBOOT_DEFINE_WIDEVINE_COUNTERS))
RETURN_ON_FAILURE(setup_widevine_counter_spaces());
RETURN_ON_FAILURE(setup_firmware_space(ctx));
return TPM_SUCCESS;
}
tpm_result_t antirollback_read_space_mrc_hash(uint32_t index, uint8_t *data, uint32_t size)
{
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", index, HASH_NV_SIZE,
size);
return TPM_CB_READ_FAILURE;
}
return read_space_mrc_hash(index, data);
}
tpm_result_t antirollback_write_space_mrc_hash(uint32_t index, const uint8_t *data, uint32_t size)
{
uint8_t spc_data[HASH_NV_SIZE];
tpm_result_t rc;
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", index, HASH_NV_SIZE,
size);
return TPM_CB_WRITE_FAILURE;
}
rc = read_space_mrc_hash(index, spc_data);
if (rc == TPM_BADINDEX) {
/*
* If space is not defined already for hash, define
* new space.
*/
VBDEBUG("TPM: Initializing hash space.\n");
return set_mrc_hash_space(index, data);
}
if (rc != TPM_SUCCESS)
return rc;
return safe_write(index, data, size);
}
tpm_result_t antirollback_lock_space_mrc_hash(uint32_t index)
{
return tlcl2_lock_nv_write(index);
}
static tpm_result_t read_space_vbios_hash(uint8_t *data)
{
RETURN_ON_FAILURE(tlcl_read(VBIOS_CACHE_NV_INDEX, data, HASH_NV_SIZE));
return TPM_SUCCESS;
}
tpm_result_t antirollback_read_space_vbios_hash(uint8_t *data, uint32_t size)
{
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", VBIOS_CACHE_NV_INDEX, HASH_NV_SIZE,
size);
return TPM_CB_READ_FAILURE;
}
return read_space_vbios_hash(data);
}
tpm_result_t antirollback_write_space_vbios_hash(const uint8_t *data, uint32_t size)
{
uint8_t spc_data[HASH_NV_SIZE];
tpm_result_t rc;
if (size != HASH_NV_SIZE) {
VBDEBUG("TPM: Incorrect buffer size for hash idx %#x. "
"(Expected=%#x Actual=%#x).\n", VBIOS_CACHE_NV_INDEX, HASH_NV_SIZE,
size);
return TPM_CB_WRITE_FAILURE;
}
rc = read_space_vbios_hash(spc_data);
if (rc == TPM_BADINDEX) {
/*
* If space is not defined already for hash, define
* new space.
*/
VBDEBUG("TPM: Initializing hash space.\n");
return setup_space("VBIOS Cache Hash", VBIOS_CACHE_NV_INDEX, data, HASH_NV_SIZE,
rw_space_attributes, NULL, 0);
}
if (rc != TPM_SUCCESS)
return rc;
return safe_write(VBIOS_CACHE_NV_INDEX, data, size);
}

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src/security/vboot/secdata_tpm_private.h Normal file
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/* SPDX-License-Identifier: BSD-3-Clause */
#ifndef __VBOOT_SECDATA_TPM_PRIVATE_H__
#define __VBOOT_SECDATA_TPM_PRIVATE_H__
#include <console/console.h>
#include <security/tpm/tis.h>
#include <vb2_api.h>
#define VBDEBUG(format, args...) \
printk(BIOS_INFO, "%s():%d: " format, __func__, __LINE__, ## args)
#define RETURN_ON_FAILURE(tpm_cmd) do { \
tpm_result_t rc_; \
if ((rc_ = (tpm_cmd)) != TPM_SUCCESS) { \
VBDEBUG("Antirollback: %08x returned by " #tpm_cmd "\n", \
(tpm_result_t)rc_); \
return rc_; \
} \
} while (0)
tpm_result_t safe_write(uint32_t index, const void *data, uint32_t length);
tpm_result_t factory_initialize_tpm1(struct vb2_context *ctx);
tpm_result_t factory_initialize_tpm2(struct vb2_context *ctx);
#endif /* __VBOOT_SECDATA_TPM_PRIVATE_H__ */