keys, trusted: seal/unseal with TPM 2.0 chips

Call tpm_seal_trusted() and tpm_unseal_trusted() for TPM 2.0 chips.
We require explicit 'keyhandle=' option because there's no a fixed
storage root key inside TPM2 chips.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Andreas Fuchs <andreas.fuchs@sit.fraunhofer.de>
Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (on TPM 1.2)
Tested-by: Chris J Arges <chris.j.arges@canonical.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Kevin Strasser <kevin.strasser@intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

security/keys/trusted.c

@@ -862,11 +862,18 @@ static int datablob_parse(char *datablob, struct trusted_key_payload *p,
 static struct trusted_key_options *trusted_options_alloc(void)
 {
 	struct trusted_key_options *options;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(TPM_ANY_NUM);
+	if (tpm2 < 0)
+		return NULL;
 
 	options = kzalloc(sizeof *options, GFP_KERNEL);
 	if (options) {
 		/* set any non-zero defaults */
 		options->keytype = SRK_keytype;
+
+		if (!tpm2)
 			options->keyhandle = SRKHANDLE;
 	}
 	return options;
@@ -905,6 +912,11 @@ static int trusted_instantiate(struct key *key,
 	int ret = 0;
 	int key_cmd;
 	size_t key_len;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(TPM_ANY_NUM);
+	if (tpm2 < 0)
+		return tpm2;
 
 	if (datalen <= 0 || datalen > 32767 || !prep->data)
 		return -EINVAL;
@@ -932,11 +944,19 @@ static int trusted_instantiate(struct key *key,
 		goto out;
 	}
 
+	if (!options->keyhandle) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	dump_payload(payload);
 	dump_options(options);
 
 	switch (key_cmd) {
 	case Opt_load:
+		if (tpm2)
+			ret = tpm_unseal_trusted(TPM_ANY_NUM, payload, options);
+		else
 			ret = key_unseal(payload, options);
 		dump_payload(payload);
 		dump_options(options);
@@ -950,6 +970,9 @@ static int trusted_instantiate(struct key *key,
 			pr_info("trusted_key: key_create failed (%d)\n", ret);
 			goto out;
 		}
+		if (tpm2)
+			ret = tpm_seal_trusted(TPM_ANY_NUM, payload, options);
+		else
 			ret = key_seal(payload, options);
 		if (ret < 0)
 			pr_info("trusted_key: key_seal failed (%d)\n", ret);
@@ -1018,6 +1041,13 @@ static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
 		kfree(new_p);
 		goto out;
 	}
+
+	if (!new_o->keyhandle) {
+		ret = -EINVAL;
+		kfree(new_p);
+		goto out;
+	}
+
 	/* copy old key values, and reseal with new pcrs */
 	new_p->migratable = p->migratable;
 	new_p->key_len = p->key_len;