[PATCH 3/3] tpm: add the crypto algorithm identifier to active_bank_info

In preparation for the patch introducing a function to pass supported TPM
algorithms and digest sizes to TPM users, the crypto algorithm identifier
is added to the active_bank_info structure.

All members of active_bank_info are necessary: TPM algorithm identifiers
will be used to create an event log (they are included in the Crypto Agile
format defined by TCG); crypto identifiers will be used to calculate
digests using the crypto subsystem; digest sizes will be used to truncate
digests calculated with different algorithms.

Signed-off-by: Roberto Sassu <[email protected]>
---
 drivers/char/tpm/tpm2-cmd.c | 2 ++
 include/linux/tpm.h         | 1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index b1356be..8c58f6e 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -946,6 +946,7 @@ static int tpm2_init_active_bank_info(struct tpm_chip *chip, u16 alg_id,
 	int rc, i;
 
 	active_bank->alg_id = alg_id;
+	active_bank->crypto_id = HASH_ALGO__LAST;
 
 	for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
 		enum hash_algo crypto_algo = tpm2_hash_map[i].crypto_id;
@@ -954,6 +955,7 @@ static int tpm2_init_active_bank_info(struct tpm_chip *chip, u16 alg_id,
 			continue;
 
 		active_bank->digest_size = hash_digest_size[crypto_algo];
+		active_bank->crypto_id = crypto_algo;
 		return 0;
 	}
 
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 3ecce21..fc927f3 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -54,6 +54,7 @@ struct tpm_class_ops {
 
 struct active_bank_info {
 	u16 alg_id;
+	u16 crypto_id;
 	u16 digest_size;
 };
 
-- 
2.9.3