tpm-v2: add support for mapping algorithm names to algos

replace tpm2_supported_algorithms with an array of structures
relating algorithm names, to TCG id's, digest length and mask values.

While at it fix the tpm2_algorithm_to_mask to return the proper value.

Cc: Eddie James <eajames@linux.ibm.com>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Fixes: 97707f12fdab ("tpm: Support boot measurements")
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index 33dd103767c402809729b188297daf370b79435d..c9d5cb6d3e5a86937299205779fcba563ab7fc99 100644 (file)
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -386,7 +386,54 @@ enum tpm2_algorithms {
        TPM2_ALG_SM3_256        = 0x12,
 };
 
-extern const enum tpm2_algorithms tpm2_supported_algorithms[4];
+/**
+ * struct digest_info - details of supported digests
+ *
+ * @hash_name:                 hash name
+ * @hash_alg:                  hash algorithm id
+ * @hash_mask:                 hash registry mask
+ * @hash_len:                  hash digest length
+ */
+struct digest_info {
+       const char *hash_name;
+       u16 hash_alg;
+       u32 hash_mask;
+       u16 hash_len;
+};
+
+/* Algorithm Registry */
+#define TCG2_BOOT_HASH_ALG_SHA1    0x00000001
+#define TCG2_BOOT_HASH_ALG_SHA256  0x00000002
+#define TCG2_BOOT_HASH_ALG_SHA384  0x00000004
+#define TCG2_BOOT_HASH_ALG_SHA512  0x00000008
+#define TCG2_BOOT_HASH_ALG_SM3_256 0x00000010
+
+static const struct digest_info hash_algo_list[] = {
+       {
+               "sha1",
+               TPM2_ALG_SHA1,
+               TCG2_BOOT_HASH_ALG_SHA1,
+               TPM2_SHA1_DIGEST_SIZE,
+       },
+       {
+               "sha256",
+               TPM2_ALG_SHA256,
+               TCG2_BOOT_HASH_ALG_SHA256,
+               TPM2_SHA256_DIGEST_SIZE,
+       },
+       {
+               "sha384",
+               TPM2_ALG_SHA384,
+               TCG2_BOOT_HASH_ALG_SHA384,
+               TPM2_SHA384_DIGEST_SIZE,
+       },
+       {
+               "sha512",
+               TPM2_ALG_SHA512,
+               TCG2_BOOT_HASH_ALG_SHA512,
+               TPM2_SHA512_DIGEST_SIZE,
+       },
+};
 
 static inline u16 tpm2_algorithm_to_len(enum tpm2_algorithms a)
 {
@@ -404,8 +451,6 @@ static inline u16 tpm2_algorithm_to_len(enum tpm2_algorithms a)
        }
 }
 
-#define tpm2_algorithm_to_mask(a)      (1 << (a))
-
 /* NV index attributes */
 enum tpm_index_attrs {
        TPMA_NV_PPWRITE         = 1UL << 0,
@@ -965,4 +1010,30 @@ u32 tpm2_enable_nvcommits(struct udevice *dev, uint vendor_cmd,
  */
 u32 tpm2_auto_start(struct udevice *dev);
 
+/**
+ * tpm2_name_to_algorithm() - Return an algorithm id given a supported
+ *                           algorithm name
+ *
+ * @name: algorithm name
+ * Return: enum tpm2_algorithms or -EINVAL
+ */
+enum tpm2_algorithms tpm2_name_to_algorithm(const char *name);
+
+/**
+ * tpm2_algorithm_name() - Return an algorithm name string for a
+ *                        supported algorithm id
+ *
+ * @algorithm_id: algorithm defined in enum tpm2_algorithms
+ * Return: algorithm name string or ""
+ */
+const char *tpm2_algorithm_name(enum tpm2_algorithms);
+
+/**
+ * tpm2_algorithm_to_mask() - Get a TCG hash mask for algorithm
+ *
+ * @hash_alg: TCG defined algorithm
+ * Return: TCG hashing algorithm bitmaps (or 0 if algo not supported)
+ */
+u32 tpm2_algorithm_to_mask(enum tpm2_algorithms);
+
 #endif /* __TPM_V2_H */

diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c
index b07e0099c27e54b38d8cb11d2eedee14ede51907..945aafb847d85ecb13fa04d254d04a1dd0af9a7f 100644 (file)
--- a/lib/efi_loader/efi_tcg2.c
+++ b/lib/efi_loader/efi_tcg2.c
@@ -414,10 +414,10 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
        }
 
        digest_list->count = 0;
-       for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); i++) {
-               u16 hash_alg = tpm2_supported_algorithms[i];
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); i++) {
+               u16 hash_alg = hash_algo_list[i].hash_alg;
 
-               if (!(active & tpm2_algorithm_to_mask(hash_alg)))
+               if (!(active & hash_algo_list[i].hash_mask))
                        continue;
                switch (hash_alg) {
                case TPM2_ALG_SHA1:

diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index 68eaaa639f89d97965eaccda5d67ff3723f6c4ea..a67daed2f3c1d3e1a5ea65b72aefb98e9f3bd99b 100644 (file)
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -22,13 +22,6 @@
 
 #include "tpm-utils.h"
 
-const enum tpm2_algorithms tpm2_supported_algorithms[4] = {
-       TPM2_ALG_SHA1,
-       TPM2_ALG_SHA256,
-       TPM2_ALG_SHA384,
-       TPM2_ALG_SHA512,
-};
-
 int tcg2_get_active_pcr_banks(struct udevice *dev, u32 *active_pcr_banks)
 {
        u32 supported = 0;
@@ -82,14 +75,11 @@ int tcg2_create_digest(struct udevice *dev, const u8 *input, u32 length,
                return rc;
 
        digest_list->count = 0;
-       for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); ++i) {
-               u32 mask =
-                       tpm2_algorithm_to_mask(tpm2_supported_algorithms[i]);
-
-               if (!(active & mask))
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
+               if (!(active & hash_algo_list[i].hash_mask))
                        continue;
 
-               switch (tpm2_supported_algorithms[i]) {
+               switch (hash_algo_list[i].hash_alg) {
                case TPM2_ALG_SHA1:
                        sha1_starts(&ctx);
                        sha1_update(&ctx, input, length);
@@ -116,12 +106,12 @@ int tcg2_create_digest(struct udevice *dev, const u8 *input, u32 length,
                        break;
                default:
                        printf("%s: unsupported algorithm %x\n", __func__,
-                              tpm2_supported_algorithms[i]);
+                              hash_algo_list[i].hash_alg);
                        continue;
                }
 
                digest_list->digests[digest_list->count].hash_alg =
-                       tpm2_supported_algorithms[i];
+                       hash_algo_list[i].hash_alg;
                memcpy(&digest_list->digests[digest_list->count].digest, final,
                       len);
                digest_list->count++;
@@ -198,7 +188,6 @@ static int tcg2_log_init(struct udevice *dev, struct tcg2_event_log *elog)
        u32 count = 0;
        u32 log_size;
        u32 active;
-       u32 mask;
        size_t i;
        u16 len;
        int rc;
@@ -208,13 +197,11 @@ static int tcg2_log_init(struct udevice *dev, struct tcg2_event_log *elog)
                return rc;
 
        event_size = offsetof(struct tcg_efi_spec_id_event, digest_sizes);
-       for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); ++i) {
-               mask = tpm2_algorithm_to_mask(tpm2_supported_algorithms[i]);
-
-               if (!(active & mask))
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
+               if (!(active & hash_algo_list[i].hash_mask))
                        continue;
 
-               switch (tpm2_supported_algorithms[i]) {
+               switch (hash_algo_list[i].hash_alg) {
                case TPM2_ALG_SHA1:
                case TPM2_ALG_SHA256:
                case TPM2_ALG_SHA384:
@@ -253,17 +240,15 @@ static int tcg2_log_init(struct udevice *dev, struct tcg2_event_log *elog)
        put_unaligned_le32(count, &ev->number_of_algorithms);
 
        count = 0;
-       for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); ++i) {
-               mask = tpm2_algorithm_to_mask(tpm2_supported_algorithms[i]);
-
-               if (!(active & mask))
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
+               if (!(active & hash_algo_list[i].hash_mask))
                        continue;
 
-               len = tpm2_algorithm_to_len(tpm2_supported_algorithms[i]);
+               len = hash_algo_list[i].hash_len;
                if (!len)
                        continue;
 
-               put_unaligned_le16(tpm2_supported_algorithms[i],
+               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++;
@@ -304,7 +289,7 @@ static int tcg2_replay_eventlog(struct tcg2_event_log *elog,
                pos = offsetof(struct tcg_pcr_event2, digests) +
                        offsetof(struct tpml_digest_values, count);
                count = get_unaligned_le32(log + pos);
-               if (count > ARRAY_SIZE(tpm2_supported_algorithms) ||
+               if (count > ARRAY_SIZE(hash_algo_list) ||
                    (digest_list->count && digest_list->count != count))
                        return 0;
 
@@ -407,7 +392,7 @@ static int tcg2_log_parse(struct udevice *dev, struct tcg2_event_log *elog)
                return 0;
 
        count = get_unaligned_le32(&event->number_of_algorithms);
-       if (count > ARRAY_SIZE(tpm2_supported_algorithms))
+       if (count > ARRAY_SIZE(hash_algo_list))
                return 0;
 
        calc_size = offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
@@ -1110,7 +1095,7 @@ int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr, u32 *active_pcr,
         * We only support 5 algorithms for now so check against that
         * instead of TPM2_NUM_PCR_BANKS
         */
-       if (pcrs.count > ARRAY_SIZE(tpm2_supported_algorithms) ||
+       if (pcrs.count > ARRAY_SIZE(hash_algo_list) ||
            pcrs.count < 1) {
                printf("%s: too many pcrs: %u\n", __func__, pcrs.count);
                return -EMSGSIZE;
@@ -1555,3 +1540,40 @@ u32 tpm2_enable_nvcommits(struct udevice *dev, uint vendor_cmd,
 
        return 0;
 }
+
+enum tpm2_algorithms tpm2_name_to_algorithm(const char *name)
+{
+       size_t i;
+
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
+               if (!strcasecmp(name, hash_algo_list[i].hash_name))
+                       return hash_algo_list[i].hash_alg;
+       }
+       printf("%s: unsupported algorithm %s\n", __func__, name);
+
+       return -EINVAL;
+}
+
+const char *tpm2_algorithm_name(enum tpm2_algorithms algo)
+{
+       size_t i;
+
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); ++i) {
+               if (hash_algo_list[i].hash_alg == algo)
+                       return hash_algo_list[i].hash_name;
+       }
+
+       return "";
+}
+
+u32 tpm2_algorithm_to_mask(enum tpm2_algorithms algo)
+{
+       size_t i;
+
+       for (i = 0; i < ARRAY_SIZE(hash_algo_list); i++) {
+               if (hash_algo_list[i].hash_alg == algo)
+                       return hash_algo_list[i].hash_mask;
+       }
+
+       return 0;
+}