/**
* Initialize the state descriptor for the specified hash algorithm.
*
* An internal routine to allocate the hash-specific state in \a hdesc for
* use with cfs_crypto_hash_digest() to compute the hash of a single message,
* though possibly in multiple chunks. The descriptor internal state should
* be freed with cfs_crypto_hash_final().
*
* \param[in] hash_alg hash algorithm id (CFS_HASH_ALG_*)
* \param[out] type pointer to the hash description in hash_types[] array
* \param[in,out] req ahash request to be initialized
* \param[in] key initial hash value/state, NULL to use default value
* \param[in] key_len length of \a key
*
* \retval 0 on success
* \retval negative errno on failure
*/
static int cfs_crypto_hash_alloc(enum cfs_crypto_hash_alg hash_alg,
const struct cfs_crypto_hash_type **type,
struct ahash_request **req,
unsigned char *key,
unsigned int key_len)
{
struct crypto_ahash *tfm;
int err = 0;
*type = cfs_crypto_hash_type(hash_alg);
if (*type == NULL) {
CWARN("Unsupported hash algorithm id = %d, max id is %d\n",
hash_alg, CFS_HASH_ALG_MAX);
return -EINVAL;
}
tfm = crypto_alloc_ahash((*type)->cht_name, 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm)) {
CDEBUG(D_INFO, "Failed to alloc crypto hash %s\n",
(*type)->cht_name);
return PTR_ERR(tfm);
}
*req = ahash_request_alloc(tfm, GFP_KERNEL);
if (!*req) {
CDEBUG(D_INFO, "Failed to alloc ahash_request for %s\n",
(*type)->cht_name);
crypto_free_ahash(tfm);
return -ENOMEM;
}
ahash_request_set_callback(*req, 0, NULL, NULL);
if (key)
err = crypto_ahash_setkey(tfm, key, key_len);
else if ((*type)->cht_key != 0)
err = crypto_ahash_setkey(tfm,
(unsigned char *)&((*type)->cht_key),
(*type)->cht_size);
if (err != 0) {
ahash_request_free(*req);
crypto_free_ahash(tfm);
return err;
}
CDEBUG(D_INFO, "Using crypto hash: %s (%s) speed %d MB/s\n",
crypto_ahash_alg_name(tfm), crypto_ahash_driver_name(tfm),
cfs_crypto_hash_speeds[hash_alg]);
err = crypto_ahash_init(*req);
if (err) {
ahash_request_free(*req);
crypto_free_ahash(tfm);
}
return err;
}
/**
* Initialize the state descriptor for the specified hash algorithm.
*
* An internal routine to allocate the hash-specific state in \a hdesc for
* use with cfs_crypto_hash_digest() to compute the hash of a single message,
* though possibly in multiple chunks. The descriptor internal state should
* be freed with cfs_crypto_hash_final().
*
* \param[in] hash_alg hash algorithm id (CFS_HASH_ALG_*)
* \param[out] type pointer to the hash description in hash_types[] array
* \param[in,out] req ahash request to be initialized
* \param[in] key initial hash value/state, NULL to use default value
* \param[in] key_len length of \a key
*
* \retval 0 on success
* \retval negative errno on failure
*/
static int cfs_crypto_hash_alloc(enum cfs_crypto_hash_alg hash_alg,
const struct cfs_crypto_hash_type **type,
struct ahash_request **req,
unsigned char *key,
unsigned int key_len)
{
struct crypto_ahash *tfm;
int err = 0;
*type = cfs_crypto_hash_type(hash_alg);
if (!*type) {
CWARN("Unsupported hash algorithm id = %d, max id is %d\n",
hash_alg, CFS_HASH_ALG_MAX);
return -EINVAL;
}
/* Keys are only supported for the hmac version */
if (key && key_len > 0) {
char *algo_name;
algo_name = kasprintf(GFP_KERNEL, "hmac(%s)",
(*type)->cht_name);
if (!algo_name)
return -ENOMEM;
tfm = crypto_alloc_ahash(algo_name, 0, CRYPTO_ALG_ASYNC);
kfree(algo_name);
} else {
tfm = crypto_alloc_ahash((*type)->cht_name, 0,
CRYPTO_ALG_ASYNC);
}
if (IS_ERR(tfm)) {
CDEBUG(D_INFO, "Failed to alloc crypto hash %s\n",
(*type)->cht_name);
return PTR_ERR(tfm);
}
*req = ahash_request_alloc(tfm, GFP_KERNEL);
if (!*req) {
CDEBUG(D_INFO, "Failed to alloc ahash_request for %s\n",
(*type)->cht_name);
GOTO(out_free_tfm, err = -ENOMEM);
}
ahash_request_set_callback(*req, 0, NULL, NULL);
if (key)
err = crypto_ahash_setkey(tfm, key, key_len);
else if ((*type)->cht_key != 0)
err = crypto_ahash_setkey(tfm,
(unsigned char *)&((*type)->cht_key),
(*type)->cht_size);
if (err)
GOTO(out_free_req, err);
CDEBUG(D_INFO, "Using crypto hash: %s (%s) speed %d MB/s\n",
crypto_ahash_alg_name(tfm), crypto_ahash_driver_name(tfm),
cfs_crypto_hash_speeds[hash_alg]);
err = crypto_ahash_init(*req);
if (err) {
out_free_req:
ahash_request_free(*req);
out_free_tfm:
crypto_free_ahash(tfm);
}
return err;
}
