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Diffstat (limited to 'crypto/asymmetric_keys/asym_tpm.c')
-rw-r--r--crypto/asymmetric_keys/asym_tpm.c43
1 files changed, 14 insertions, 29 deletions
diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c
index 5d4c270463f6..76d2ce3a1b5b 100644
--- a/crypto/asymmetric_keys/asym_tpm.c
+++ b/crypto/asymmetric_keys/asym_tpm.c
@@ -276,6 +276,10 @@ static int tpm_sign(struct tpm_buf *tb,
return datalen;
}
+
+/* Room to fit two u32 zeros for algo id and parameters length. */
+#define SETKEY_PARAMS_SIZE (sizeof(u32) * 2)
+
/*
* Maximum buffer size for the BER/DER encoded public key. The public key
* is of the form SEQUENCE { INTEGER n, INTEGER e } where n is a maximum 2048
@@ -286,8 +290,9 @@ static int tpm_sign(struct tpm_buf *tb,
* - 257 bytes of n
* - max 2 bytes for INTEGER e type/length
* - 3 bytes of e
+ * - 4+4 of zeros for set_pub_key parameters (SETKEY_PARAMS_SIZE)
*/
-#define PUB_KEY_BUF_SIZE (4 + 4 + 257 + 2 + 3)
+#define PUB_KEY_BUF_SIZE (4 + 4 + 257 + 2 + 3 + SETKEY_PARAMS_SIZE)
/*
* Provide a part of a description of the key for /proc/keys.
@@ -364,6 +369,8 @@ static uint32_t derive_pub_key(const void *pub_key, uint32_t len, uint8_t *buf)
cur = encode_tag_length(cur, 0x02, sizeof(e));
memcpy(cur, e, sizeof(e));
cur += sizeof(e);
+ /* Zero parameters to satisfy set_pub_key ABI. */
+ memset(cur, 0, SETKEY_PARAMS_SIZE);
return cur - buf;
}
@@ -744,12 +751,10 @@ static int tpm_key_verify_signature(const struct key *key,
struct crypto_wait cwait;
struct crypto_akcipher *tfm;
struct akcipher_request *req;
- struct scatterlist sig_sg, digest_sg;
+ struct scatterlist src_sg[2];
char alg_name[CRYPTO_MAX_ALG_NAME];
uint8_t der_pub_key[PUB_KEY_BUF_SIZE];
uint32_t der_pub_key_len;
- void *output;
- unsigned int outlen;
int ret;
pr_devel("==>%s()\n", __func__);
@@ -781,37 +786,17 @@ static int tpm_key_verify_signature(const struct key *key,
if (!req)
goto error_free_tfm;
- ret = -ENOMEM;
- outlen = crypto_akcipher_maxsize(tfm);
- output = kmalloc(outlen, GFP_KERNEL);
- if (!output)
- goto error_free_req;
-
- sg_init_one(&sig_sg, sig->s, sig->s_size);
- sg_init_one(&digest_sg, output, outlen);
- akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size,
- outlen);
+ sg_init_table(src_sg, 2);
+ sg_set_buf(&src_sg[0], sig->s, sig->s_size);
+ sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
+ akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
+ sig->digest_size);
crypto_init_wait(&cwait);
akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
CRYPTO_TFM_REQ_MAY_SLEEP,
crypto_req_done, &cwait);
-
- /* Perform the verification calculation. This doesn't actually do the
- * verification, but rather calculates the hash expected by the
- * signature and returns that to us.
- */
ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
- if (ret)
- goto out_free_output;
-
- /* Do the actual verification step. */
- if (req->dst_len != sig->digest_size ||
- memcmp(sig->digest, output, sig->digest_size) != 0)
- ret = -EKEYREJECTED;
-out_free_output:
- kfree(output);
-error_free_req:
akcipher_request_free(req);
error_free_tfm:
crypto_free_akcipher(tfm);