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security/tpm: Fix TCPA log feature

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Until now the TCPA log wasn't working correctly.

* Refactor TCPA log code.
* Add TCPA log dump fucntion.
* Make TCPA log available in bootblock.
* Fix TCPA log formatting.
* Add x86 and Cavium memory for early log.

Change-Id: Ic93133531b84318f48940d34bded48cbae739c44
Signed-off-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/29563
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
This commit is contained in:
Philipp Deppenwiese
2018-11-10 00:35:02 +01:00
parent 7a732b4781
commit c9b7d1fb57
20 changed files with 376 additions and 92 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
src/security/tpm/Makefile.inc
View File

@@ -12,11 +12,16 @@ postcar-$(CONFIG_VBOOT) += tss/tcg-1.2/tss.c
## TSPI
ramstage-y += tspi/tspi.c tspi/log.c
romstage-y += tspi/tspi.c tspi/log.c
ramstage-y += tspi/tspi.c
romstage-y += tspi/tspi.c
verstage-$(CONFIG_VBOOT) += tspi/tspi.c tspi/log.c
postcar-$(CONFIG_VBOOT) += tspi/tspi.c tspi/log.c
verstage-$(CONFIG_VBOOT) += tspi/tspi.c
postcar-$(CONFIG_VBOOT) += tspi/tspi.c
ramstage-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
romstage-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
verstage-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
postcar-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
endif # CONFIG_TPM1
@@ -36,10 +41,15 @@ postcar-$(CONFIG_VBOOT) += tss/tcg-2.0/tss.c
## TSPI
ramstage-y += tspi/tspi.c tspi/log.c
romstage-y += tspi/tspi.c tspi/log.c
ramstage-y += tspi/tspi.c
romstage-y += tspi/tspi.c
verstage-$(CONFIG_VBOOT) += tspi/tspi.c tspi/log.c
postcar-$(CONFIG_VBOOT) += tspi/tspi.c tspi/log.c
verstage-$(CONFIG_VBOOT) += tspi/tspi.c
postcar-$(CONFIG_VBOOT) += tspi/tspi.c
ramstage-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
romstage-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
verstage-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
postcar-$(CONFIG_VBOOT_MEASURED_BOOT) += tspi/log.c
endif # CONFIG_TPM2

28
src/security/tpm/tspi.h
View File

@@ -21,26 +21,46 @@
#include <security/tpm/tss.h>
#include <commonlib/tcpa_log_serialized.h>
#include <commonlib/region.h>
#include <vb2_api.h>
#define TPM_PCR_MAX_LEN 64
#define HASH_DATA_CHUNK_SIZE 1024
#define TPM_PCR_MAX_LEN 64
#define HASH_DATA_CHUNK_SIZE 1024
/**
* Clears the pre-RAM tcpa log data and initializes
* any content with default values
*/
void tcpa_preram_log_clear(void);
/**
* Add table entry for cbmem TCPA log.
* @param name Name of the hashed data
* @param pcr PCR used to extend hashed data
* @param diget_algo sets the digest algorithm
* @param digest sets the hash extended into the tpm
* @param digest_len the length of the digest
*/
void tcpa_log_add_table_entry(const char *name, const uint32_t pcr,
enum vb2_hash_algorithm digest_algo,
const uint8_t *digest,
const size_t digest_length);
const size_t digest_len);
/**
* Dump TCPA log entries on console
*/
void tcpa_log_dump(void *unused);
/**
* Ask vboot for a digest and extend a TPM PCR with it.
* @param pcr sets the pcr index
* @param diget_algo sets the digest algorithm
* @param digest sets the hash to extend into the tpm
* @param digest_len the length of the digest
* @param name sets additional info where the digest comes from
* @return TPM_SUCCESS on success. If not a tpm error is returned
*/
uint32_t tpm_extend_pcr(int pcr, uint8_t *digest, size_t digest_len,
uint32_t tpm_extend_pcr(int pcr, enum vb2_hash_algorithm digest_algo,
uint8_t *digest, size_t digest_len,
const char *name);
/**

165
src/security/tpm/tspi/log.c
View File

@@ -14,67 +14,162 @@
*/
#include <string.h>
#include <cbmem.h>
#include <console/console.h>
#include <security/tpm/tspi.h>
#include <arch/early_variables.h>
#include <fmap.h>
#include <region_file.h>
#include <string.h>
#include <security/vboot/symbols.h>
#include <cbmem.h>
#include <bootstate.h>
static struct tcpa_table *tcpa_cbmem_init(void)
{
MAYBE_STATIC struct tcpa_table *tclt = NULL;
if (tclt)
return tclt;
if (cbmem_possibly_online()) {
tclt = cbmem_find(CBMEM_ID_TCPA_LOG);
if (!tclt) {
size_t tcpa_log_len = sizeof(struct tcpa_table) +
MAX_TCPA_LOG_ENTRIES * sizeof(struct tcpa_entry);
tclt = cbmem_add(CBMEM_ID_TCPA_LOG, tcpa_log_len);
if (tclt) {
tclt->max_entries = MAX_TCPA_LOG_ENTRIES;
tclt->num_entries = 0;
}
}
}
return tclt;
}
static struct tcpa_table *tcpa_log_init(void)
{
MAYBE_STATIC struct tcpa_table *tclt = NULL;
if (!cbmem_possibly_online())
return NULL;
if (tclt != NULL)
return tclt;
tclt = (struct tcpa_table *) cbmem_entry_find(CBMEM_ID_TCPA_LOG);
if (tclt)
return tclt;
tclt = cbmem_add(CBMEM_ID_TCPA_LOG,
sizeof(struct tcpa_table) +
MAX_TCPA_LOG_ENTRIES *
sizeof(struct tcpa_entry));
if (!tclt) {
printk(BIOS_ERR, "ERROR: Could not create TCPA log table\n");
return NULL;
/* We are dealing here with pre CBMEM environment.
* If cbmem isn't available use CAR or SRAM */
if (!cbmem_possibly_online() &&
!IS_ENABLED(CONFIG_VBOOT_RETURN_FROM_VERSTAGE))
return (struct tcpa_table *)_vboot2_tpm_log;
else if (ENV_ROMSTAGE &&
!IS_ENABLED(CONFIG_VBOOT_RETURN_FROM_VERSTAGE)) {
tclt = tcpa_cbmem_init();
if (!tclt)
return (struct tcpa_table *)_vboot2_tpm_log;
} else {
tclt = tcpa_cbmem_init();
}
tclt->max_entries = MAX_TCPA_LOG_ENTRIES;
tclt->num_entries = 0;
printk(BIOS_DEBUG, "TCPA log created at %p\n", tclt);
return tclt;
}
void tcpa_log_add_table_entry(const char *name, const uint32_t pcr,
const uint8_t *digest, const size_t digest_length)
void tcpa_log_dump(void *unused)
{
int i, j;
struct tcpa_table *tclt;
struct tcpa_entry *tce;
tclt = tcpa_log_init();
if (!tclt)
return;
if (tclt->num_entries == tclt->max_entries) {
printk(BIOS_WARNING, "ERROR: TCPA log table is full\n");
printk(BIOS_INFO, "coreboot TCPA measurements:\n\n");
for (i = 0; i < tclt->num_entries; i++) {
struct tcpa_entry *tce = &tclt->entries[i];
if (tce) {
printk(BIOS_INFO, " PCR-%u ", tce->pcr);
for (j = 0; j < tce->digest_length; j++)
printk(BIOS_INFO, "%02x", tce->digest[j]);
printk(BIOS_INFO, " %s [%s]\n",
tce->digest_type, tce->name);
}
}
printk(BIOS_INFO, "\n");
}
void tcpa_log_add_table_entry(const char *name, const uint32_t pcr,
enum vb2_hash_algorithm digest_algo,
const uint8_t *digest,
const size_t digest_len)
{
struct tcpa_table *tclt = tcpa_log_init();
if (!tclt) {
printk(BIOS_WARNING, "TCPA: Log non-existent!\n");
return;
}
tce = &tclt->entries[tclt->num_entries++];
if (tclt->num_entries >= tclt->max_entries) {
printk(BIOS_WARNING, "TCPA: TCPA log table is full\n");
return;
}
if (!name) {
printk(BIOS_WARNING, "TCPA: TCPA entry name not set\n");
return;
}
struct tcpa_entry *tce = &tclt->entries[tclt->num_entries++];
strncpy(tce->name, name, TCPA_PCR_HASH_NAME - 1);
tce->pcr = pcr;
if (digest_length > TCPA_DIGEST_MAX_LENGTH) {
printk(BIOS_WARNING, "ERROR: PCR digest too long for TCPA log entry\n");
if (digest_len > TCPA_DIGEST_MAX_LENGTH) {
printk(BIOS_WARNING, "TCPA: PCR digest too long for TCPA log entry\n");
return;
}
memcpy(tce->digest, digest, digest_length);
tce->digest_length = digest_length;
strncpy(tce->digest_type,
vb2_get_hash_algorithm_name(digest_algo),
TCPA_PCR_HASH_LEN - 1);
tce->digest_length = digest_len;
memcpy(tce->digest, digest, tce->digest_length);
}
void tcpa_preram_log_clear(void)
{
printk(BIOS_INFO, "TCPA: Clearing coreboot TCPA log\n");
struct tcpa_table *tclt = (struct tcpa_table *)_vboot2_tpm_log;
tclt->max_entries = MAX_TCPA_LOG_ENTRIES;
tclt->num_entries = 0;
}
#if !IS_ENABLED(CONFIG_VBOOT_RETURN_FROM_VERSTAGE)
static void recover_tcpa_log(int is_recovery)
{
struct tcpa_table *preram_log = (struct tcpa_table *)_vboot2_tpm_log;
struct tcpa_table *ram_log = NULL;
int i;
if (preram_log->num_entries > MAX_PRERAM_TCPA_LOG_ENTRIES) {
printk(BIOS_WARNING, "TCPA: Pre-RAM TCPA log is too full, possible corruption\n");
return;
}
ram_log = tcpa_cbmem_init();
if (!ram_log) {
printk(BIOS_WARNING, "TCPA: CBMEM not available something went wrong\n");
return;
}
for (i = 0; i < preram_log->num_entries; i++) {
struct tcpa_entry *tce = &ram_log->entries[ram_log->num_entries++];
strncpy(tce->name, preram_log->entries[i].name, TCPA_PCR_HASH_NAME - 1);
tce->pcr = preram_log->entries[i].pcr;
if (preram_log->entries[i].digest_length > TCPA_DIGEST_MAX_LENGTH) {
printk(BIOS_WARNING, "TCPA: PCR digest too long for TCPA log entry\n");
return;
}
strncpy(tce->digest_type, preram_log->entries[i].digest_type, TCPA_PCR_HASH_LEN - 1);
tce->digest_length = MIN(preram_log->entries[i].digest_length, TCPA_DIGEST_MAX_LENGTH);
memcpy(tce->digest, preram_log->entries[i].digest, tce->digest_length);
}
}
ROMSTAGE_CBMEM_INIT_HOOK(recover_tcpa_log);
#endif
BOOT_STATE_INIT_ENTRY(BS_PAYLOAD_BOOT, BS_ON_ENTRY, tcpa_log_dump, NULL);

15
src/security/tpm/tspi/tspi.c
View File

@@ -202,8 +202,8 @@ uint32_t tpm_clear_and_reenable(void)
return TPM_SUCCESS;
}
uint32_t tpm_extend_pcr(int pcr, uint8_t *digest,
size_t digest_len, const char *name)
uint32_t tpm_extend_pcr(int pcr, enum vb2_hash_algorithm digest_algo,
uint8_t *digest, size_t digest_len, const char *name)
{
uint32_t result;
@@ -214,6 +214,10 @@ uint32_t tpm_extend_pcr(int pcr, uint8_t *digest,
if (result != TPM_SUCCESS)
return result;
if (IS_ENABLED(CONFIG_VBOOT_MEASURED_BOOT))
tcpa_log_add_table_entry(name, pcr, digest_algo,
digest, digest_len);
return TPM_SUCCESS;
}
@@ -235,10 +239,11 @@ uint32_t tpm_measure_region(const struct region_device *rdev, uint8_t pcr,
printk(BIOS_ERR, "TPM: Can't initialize library.\n");
return result;
}
if (IS_ENABLED(CONFIG_TPM1))
if (IS_ENABLED(CONFIG_TPM1)) {
hash_alg = VB2_HASH_SHA1;
else /* CONFIG_TPM2 */
} else { /* CONFIG_TPM2 */
hash_alg = VB2_HASH_SHA256;
}
digest_len = vb2_digest_size(hash_alg);
assert(digest_len <= sizeof(digest));
@@ -267,7 +272,7 @@ uint32_t tpm_measure_region(const struct region_device *rdev, uint8_t pcr,
printk(BIOS_ERR, "TPM: Error finalizing hash.\n");
return TPM_E_HASH_ERROR;
}
result = tpm_extend_pcr(pcr, digest, digest_len, rname);
result = tpm_extend_pcr(pcr, hash_alg, digest, digest_len, rname);
if (result != TPM_SUCCESS) {
printk(BIOS_ERR, "TPM: Extending hash into PCR failed.\n");
return result;

5
src/security/vboot/secdata_tpm.c
View File

@@ -80,10 +80,11 @@ uint32_t vboot_extend_pcr(struct vb2_context *ctx, int pcr,
switch (which_digest) {
case BOOT_MODE_PCR:
return tpm_extend_pcr(pcr, buffer, size,
return tpm_extend_pcr(pcr, VB2_HASH_SHA1, buffer, size,
TPM_PCR_GBB_FLAGS_NAME);
case HWID_DIGEST_PCR:
return tpm_extend_pcr(pcr, buffer, size, TPM_PCR_GBB_HWID_NAME);
return tpm_extend_pcr(pcr, VB2_HASH_SHA256, buffer,
size, TPM_PCR_GBB_HWID_NAME);
default:
return VB2_ERROR_UNKNOWN;
}

2
src/security/vboot/symbols.h
View File

@@ -20,4 +20,6 @@
DECLARE_REGION(vboot2_work)
DECLARE_REGION(vboot2_tpm_log)
#endif /* __VBOOT_SYMBOLS_H__ */

67
src/security/vboot/vboot_crtm.c
View File

@@ -18,6 +18,36 @@
#include <security/vboot/vboot_crtm.h>
#include <security/vboot/misc.h>
/*
* This functions sets the TCPA log namespace
* for the cbfs file (region) lookup.
*/
static int create_tcpa_metadata(const struct region_device *rdev,
const char *cbfs_name, char log_string[TCPA_PCR_HASH_NAME])
{
int i;
struct region_device fmap;
const static char *fmap_cbfs_names[] = {
"COREBOOT",
"FW_MAIN_A",
"FW_MAIN_B",
"RW_LEGACY"};
for (i = 0; i < ARRAY_SIZE(fmap_cbfs_names); i++) {
if (fmap_locate_area_as_rdev(fmap_cbfs_names[i], &fmap) == 0) {
if (region_is_subregion(region_device_region(&fmap),
region_device_region(rdev))) {
snprintf(log_string, TCPA_PCR_HASH_NAME,
"FMAP: %s CBFS: %s",
fmap_cbfs_names[i], cbfs_name);
return 0;
}
}
}
return -1;
}
uint32_t vboot_init_crtm(void)
{
struct prog bootblock = PROG_INIT(PROG_BOOTBLOCK, "bootblock");
@@ -25,6 +55,10 @@ uint32_t vboot_init_crtm(void)
PROG_INIT(PROG_VERSTAGE, CONFIG_CBFS_PREFIX "/verstage");
struct prog romstage =
PROG_INIT(PROG_ROMSTAGE, CONFIG_CBFS_PREFIX "/romstage");
char tcpa_metadata[TCPA_PCR_HASH_NAME];
/* Initialize TCPE PRERAM log. */
tcpa_preram_log_clear();
/* measure bootblock from RO */
struct cbfsf bootblock_data;
@@ -32,16 +66,20 @@ uint32_t vboot_init_crtm(void)
if (fmap_locate_area_as_rdev("BOOTBLOCK", &bootblock_fmap) == 0) {
if (tpm_measure_region(&bootblock_fmap,
TPM_CRTM_PCR,
prog_name(&bootblock)))
"FMAP: BOOTBLOCK"))
return VB2_ERROR_UNKNOWN;
} else {
if (cbfs_boot_locate(&bootblock_data,
prog_name(&bootblock), NULL) == 0) {
cbfs_file_data(prog_rdev(&bootblock), &bootblock_data);
if (create_tcpa_metadata(prog_rdev(&bootblock),
prog_name(&bootblock), tcpa_metadata) < 0)
return VB2_ERROR_UNKNOWN;
if (tpm_measure_region(prog_rdev(&bootblock),
TPM_CRTM_PCR,
prog_name(&bootblock)))
TPM_CRTM_PCR,
tcpa_metadata))
return VB2_ERROR_UNKNOWN;
} else {
printk(BIOS_INFO,
@@ -57,9 +95,13 @@ uint32_t vboot_init_crtm(void)
prog_name(&romstage), NULL) == 0) {
cbfs_file_data(prog_rdev(&romstage), &romstage_data);
if (create_tcpa_metadata(prog_rdev(&romstage),
prog_name(&romstage), tcpa_metadata) < 0)
return VB2_ERROR_UNKNOWN;
if (tpm_measure_region(prog_rdev(&romstage),
TPM_CRTM_PCR,
CONFIG_CBFS_PREFIX "/romstage"))
TPM_CRTM_PCR,
tcpa_metadata))
return VB2_ERROR_UNKNOWN;
} else {
printk(BIOS_INFO,
@@ -76,9 +118,13 @@ uint32_t vboot_init_crtm(void)
prog_name(&verstage), NULL) == 0) {
cbfs_file_data(prog_rdev(&verstage), &verstage_data);
if (create_tcpa_metadata(prog_rdev(&verstage),
prog_name(&verstage), tcpa_metadata) < 0)
return VB2_ERROR_UNKNOWN;
if (tpm_measure_region(prog_rdev(&verstage),
TPM_CRTM_PCR,
CONFIG_CBFS_PREFIX "/verstage"))
TPM_CRTM_PCR,
tcpa_metadata))
return VB2_ERROR_UNKNOWN;
} else {
printk(BIOS_INFO,
@@ -114,6 +160,7 @@ uint32_t vboot_measure_cbfs_hook(struct cbfsf *fh, const char *name)
uint32_t pcr_index;
uint32_t cbfs_type;
struct region_device rdev;
char tcpa_metadata[TCPA_PCR_HASH_NAME];
if (!vb2_logic_executed())
return 0;
@@ -139,6 +186,8 @@ uint32_t vboot_measure_cbfs_hook(struct cbfsf *fh, const char *name)
break;
}
return tpm_measure_region(&rdev, pcr_index,
name);
if (create_tcpa_metadata(&rdev, name, tcpa_metadata) < 0)
return VB2_ERROR_UNKNOWN;
return tpm_measure_region(&rdev, pcr_index, tcpa_metadata);
}