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Diffstat (limited to 'lib/tpm_tcg2.c')
-rw-r--r--lib/tpm_tcg2.c190
1 files changed, 99 insertions, 91 deletions
diff --git a/lib/tpm_tcg2.c b/lib/tpm_tcg2.c
index 7f868cc8837..4134d93a358 100644
--- a/lib/tpm_tcg2.c
+++ b/lib/tpm_tcg2.c
@@ -20,38 +20,36 @@
#include <linux/unaligned/le_byteshift.h>
#include "tpm-utils.h"
-int tcg2_get_pcr_info(struct udevice *dev, u32 *supported_pcr, u32 *active_pcr,
- u32 *pcr_banks)
+int tcg2_get_pcr_info(struct udevice *dev, u32 *supported_bank, u32 *active_bank,
+ u32 *bank_num)
{
- u8 response[(sizeof(struct tpms_capability_data) -
- offsetof(struct tpms_capability_data, data))];
struct tpml_pcr_selection pcrs;
size_t i;
u32 ret;
- *supported_pcr = 0;
- *active_pcr = 0;
- *pcr_banks = 0;
- memset(response, 0, sizeof(response));
+ *supported_bank = 0;
+ *active_bank = 0;
+ *bank_num = 0;
ret = tpm2_get_pcr_info(dev, &pcrs);
if (ret)
return ret;
for (i = 0; i < pcrs.count; i++) {
- u32 hash_mask = tcg2_algorithm_to_mask(pcrs.selection[i].hash);
+ struct tpms_pcr_selection *sel = &pcrs.selection[i];
+ u32 hash_mask = tcg2_algorithm_to_mask(sel->hash);
- if (hash_mask) {
- *supported_pcr |= hash_mask;
- if (tpm2_is_active_pcr(&pcrs.selection[i]))
- *active_pcr |= hash_mask;
- } else {
- printf("%s: unknown algorithm %x\n", __func__,
- pcrs.selection[i].hash);
- }
+ if (tpm2_algorithm_supported(sel->hash))
+ *supported_bank |= hash_mask;
+ else
+ log_warning("%s: unknown algorithm %x\n", __func__,
+ sel->hash);
+
+ if (tpm2_is_active_bank(sel))
+ *active_bank |= hash_mask;
}
- *pcr_banks = pcrs.count;
+ *bank_num = pcrs.count;
return 0;
}
@@ -95,57 +93,64 @@ u32 tcg2_event_get_size(struct tpml_digest_values *digest_list)
int tcg2_create_digest(struct udevice *dev, const u8 *input, u32 length,
struct tpml_digest_values *digest_list)
{
+ struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
u8 final[sizeof(union tpmu_ha)];
+#if IS_ENABLED(CONFIG_SHA256)
sha256_context ctx_256;
+#endif
+#if IS_ENABLED(CONFIG_SHA512)
sha512_context ctx_512;
+#endif
+#if IS_ENABLED(CONFIG_SHA1)
sha1_context ctx;
- u32 active;
+#endif
size_t i;
u32 len;
- int rc;
-
- rc = tcg2_get_active_pcr_banks(dev, &active);
- if (rc)
- return rc;
digest_list->count = 0;
- for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
- if (!(active & hash_algo_list[i].hash_mask))
- continue;
+ for (i = 0; i < priv->active_bank_count; i++) {
- switch (hash_algo_list[i].hash_alg) {
+ switch (priv->active_banks[i]) {
+#if IS_ENABLED(CONFIG_SHA1)
case TPM2_ALG_SHA1:
sha1_starts(&ctx);
sha1_update(&ctx, input, length);
sha1_finish(&ctx, final);
len = TPM2_SHA1_DIGEST_SIZE;
break;
+#endif
+#if IS_ENABLED(CONFIG_SHA256)
case TPM2_ALG_SHA256:
sha256_starts(&ctx_256);
sha256_update(&ctx_256, input, length);
sha256_finish(&ctx_256, final);
len = TPM2_SHA256_DIGEST_SIZE;
break;
+#endif
+#if IS_ENABLED(CONFIG_SHA384)
case TPM2_ALG_SHA384:
sha384_starts(&ctx_512);
sha384_update(&ctx_512, input, length);
sha384_finish(&ctx_512, final);
len = TPM2_SHA384_DIGEST_SIZE;
break;
+#endif
+#if IS_ENABLED(CONFIG_SHA512)
case TPM2_ALG_SHA512:
sha512_starts(&ctx_512);
sha512_update(&ctx_512, input, length);
sha512_finish(&ctx_512, final);
len = TPM2_SHA512_DIGEST_SIZE;
break;
+#endif
default:
printf("%s: unsupported algorithm %x\n", __func__,
- hash_algo_list[i].hash_alg);
+ priv->active_banks[i]);
continue;
}
digest_list->digests[digest_list->count].hash_alg =
- hash_algo_list[i].hash_alg;
+ priv->active_banks[i];
memcpy(&digest_list->digests[digest_list->count].digest, final,
len);
digest_list->count++;
@@ -216,37 +221,17 @@ static int tcg2_log_append_check(struct tcg2_event_log *elog, u32 pcr_index,
static int tcg2_log_init(struct udevice *dev, struct tcg2_event_log *elog)
{
+ struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
struct tcg_efi_spec_id_event *ev;
struct tcg_pcr_event *log;
u32 event_size;
u32 count = 0;
u32 log_size;
- u32 active;
size_t i;
u16 len;
- int rc;
-
- rc = tcg2_get_active_pcr_banks(dev, &active);
- if (rc)
- return rc;
+ count = priv->active_bank_count;
event_size = offsetof(struct tcg_efi_spec_id_event, digest_sizes);
- for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
- if (!(active & hash_algo_list[i].hash_mask))
- continue;
-
- switch (hash_algo_list[i].hash_alg) {
- case TPM2_ALG_SHA1:
- case TPM2_ALG_SHA256:
- case TPM2_ALG_SHA384:
- case TPM2_ALG_SHA512:
- count++;
- break;
- default:
- continue;
- }
- }
-
event_size += 1 +
(sizeof(struct tcg_efi_spec_id_event_algorithm_size) * count);
log_size = offsetof(struct tcg_pcr_event, event) + event_size;
@@ -273,19 +258,11 @@ static int tcg2_log_init(struct udevice *dev, struct tcg2_event_log *elog)
ev->uintn_size = sizeof(size_t) / sizeof(u32);
put_unaligned_le32(count, &ev->number_of_algorithms);
- count = 0;
- for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
- if (!(active & hash_algo_list[i].hash_mask))
- continue;
-
- len = hash_algo_list[i].hash_len;
- if (!len)
- continue;
-
- put_unaligned_le16(hash_algo_list[i].hash_alg,
- &ev->digest_sizes[count].algorithm_id);
- put_unaligned_le16(len, &ev->digest_sizes[count].digest_size);
- count++;
+ for (i = 0; i < count; ++i) {
+ len = tpm2_algorithm_to_len(priv->active_banks[i]);
+ put_unaligned_le16(priv->active_banks[i],
+ &ev->digest_sizes[i].algorithm_id);
+ put_unaligned_le16(len, &ev->digest_sizes[i].digest_size);
}
*((u8 *)ev + (event_size - 1)) = 0;
@@ -396,7 +373,6 @@ static int tcg2_log_parse(struct udevice *dev, struct tcg2_event_log *elog)
u16 len;
int rc;
u32 i;
- u16 j;
if (elog->log_size <= offsetof(struct tcg_pcr_event, event))
return 0;
@@ -435,40 +411,51 @@ static int tcg2_log_parse(struct udevice *dev, struct tcg2_event_log *elog)
if (evsz != calc_size)
return 0;
- rc = tcg2_get_active_pcr_banks(dev, &active);
- if (rc)
- return rc;
-
+ /*
+ * Go through the algorithms the EventLog contains. If the EventLog
+ * algorithms don't match the active TPM ones exit and report the
+ * erroneous banks.
+ * We've already checked that U-Boot supports all the enabled TPM
+ * algorithms, so just check the EvenLog against the TPM active ones.
+ */
digest_list.count = 0;
log_active = 0;
-
for (i = 0; i < count; ++i) {
algo = get_unaligned_le16(&event->digest_sizes[i].algorithm_id);
mask = tcg2_algorithm_to_mask(algo);
- if (!(active & mask))
- return 0;
-
switch (algo) {
case TPM2_ALG_SHA1:
case TPM2_ALG_SHA256:
case TPM2_ALG_SHA384:
case TPM2_ALG_SHA512:
len = get_unaligned_le16(&event->digest_sizes[i].digest_size);
- if (tpm2_algorithm_to_len(algo) != len)
- return 0;
+ if (tpm2_algorithm_to_len(algo) != len) {
+ log_err("EventLog invalid algorithm length\n");
+ return -1;
+ }
digest_list.digests[digest_list.count++].hash_alg = algo;
break;
default:
- return 0;
+ /*
+ * We can ignore this if the TPM PCRs is not extended
+ * by the previous bootloader. But for now just exit
+ */
+ log_err("EventLog has unsupported algorithm 0x%x\n",
+ algo);
+ return -1;
}
-
log_active |= mask;
}
- /* Ensure the previous firmware extended all the PCRs. */
- if (log_active != active)
- return 0;
+ rc = tcg2_get_active_pcr_banks(dev, &active);
+ if (rc)
+ return rc;
+ /* If the EventLog and active algorithms don't match exit */
+ if (log_active != active) {
+ log_err("EventLog doesn't contain all active PCR banks\n");
+ return -1;
+ }
/* Read PCR0 to check if previous firmware extended the PCRs or not. */
rc = tcg2_pcr_read(dev, 0, &digest_list);
@@ -476,17 +463,13 @@ static int tcg2_log_parse(struct udevice *dev, struct tcg2_event_log *elog)
return rc;
for (i = 0; i < digest_list.count; ++i) {
- len = tpm2_algorithm_to_len(digest_list.digests[i].hash_alg);
- for (j = 0; j < len; ++j) {
- if (digest_list.digests[i].digest.sha512[j])
- break;
- }
+ u8 hash_buf[TPM2_SHA512_DIGEST_SIZE] = { 0 };
+ u16 hash_alg = digest_list.digests[i].hash_alg;
- /* PCR is non-zero; it has been extended, so skip extending. */
- if (j != len) {
+ if (memcmp((u8 *)&digest_list.digests[i].digest, hash_buf,
+ tpm2_algorithm_to_len(hash_alg)))
digest_list.count = 0;
- break;
- }
+
}
return tcg2_replay_eventlog(elog, dev, &digest_list,
@@ -569,11 +552,36 @@ int tcg2_log_prepare_buffer(struct udevice *dev, struct tcg2_event_log *elog,
bool ignore_existing_log)
{
struct tcg2_event_log log;
- int rc;
+ int rc, i;
elog->log_position = 0;
elog->found = false;
+ /*
+ * Make sure U-Boot is compiled with all the active PCRs
+ * since we are about to create an EventLog and we won't
+ * measure anything if the PCR banks don't match
+ */
+ if (!tpm2_check_active_banks(dev)) {
+ log_err("Cannot create EventLog\n");
+ log_err("Mismatch between U-Boot and TPM hash algos\n");
+ log_info("TPM:\n");
+ tpm2_print_active_banks(dev);
+ log_info("U-Boot:\n");
+ for (i = 0; i < ARRAY_SIZE(hash_algo_list); i++) {
+ const struct digest_info *algo = &hash_algo_list[i];
+ const char *str;
+
+ if (!algo->supported)
+ continue;
+
+ str = tpm2_algorithm_name(algo->hash_alg);
+ if (str)
+ log_info("%s\n", str);
+ }
+ return -EINVAL;
+ }
+
rc = tcg2_platform_get_log(dev, (void **)&log.log, &log.log_size);
if (!rc) {
log.log_position = 0;