LU-8602 libcfs: call proper crypto algo when keys are passed in

In most cases keys are not passed to cfs_crypto_hash_alloc()
but if they are then crypto_ahash_setkey() will fail. Keys
are only handled by the hmac version of the algorithm requested.
If a key is passed into cfs_crypto_hash_alloc() then we should
request the hmac version of the algorithm when calling
crypto_alloc_ahash().

Change-Id: I080d89bc864b236524ef11f50df41b750ecab9fe
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/25199
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Alexandr Boyko <c17825@cray.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/libcfs/libcfs/linux/linux-crypto.c b/libcfs/libcfs/linux/linux-crypto.c
index 1991a86..ab80142 100644 (file)
--- a/libcfs/libcfs/linux/linux-crypto.c
+++ b/libcfs/libcfs/linux/linux-crypto.c
@@ -77,13 +77,27 @@ static int cfs_crypto_hash_alloc(enum cfs_crypto_hash_alg hash_alg,
        int err = 0;
 
        *type = cfs_crypto_hash_type(hash_alg);
        int err = 0;
 
        *type = cfs_crypto_hash_type(hash_alg);

-
-       if (*type == NULL) {
+       if (!*type) {

                CWARN("Unsupported hash algorithm id = %d, max id is %d\n",
                      hash_alg, CFS_HASH_ALG_MAX);
                return -EINVAL;
        }
                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);
+
+       /* 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);
        if (IS_ERR(tfm)) {
                CDEBUG(D_INFO, "Failed to alloc crypto hash %s\n",
                       (*type)->cht_name);


@@ -94,8 +108,7 @@ static int cfs_crypto_hash_alloc(enum cfs_crypto_hash_alg hash_alg,
        if (!*req) {
                CDEBUG(D_INFO, "Failed to alloc ahash_request for %s\n",
                       (*type)->cht_name);
        if (!*req) {
                CDEBUG(D_INFO, "Failed to alloc ahash_request for %s\n",
                       (*type)->cht_name);

-               crypto_free_ahash(tfm);
-               return -ENOMEM;
+               GOTO(out_free_tfm, err = -ENOMEM);

        }
 
        ahash_request_set_callback(*req, 0, NULL, NULL);
        }
 
        ahash_request_set_callback(*req, 0, NULL, NULL);


@@ -106,12 +119,8 @@ static int cfs_crypto_hash_alloc(enum cfs_crypto_hash_alg hash_alg,
                err = crypto_ahash_setkey(tfm,
                                         (unsigned char *)&((*type)->cht_key),
                                         (*type)->cht_size);
                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;
-       }
+       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),
 
        CDEBUG(D_INFO, "Using crypto hash: %s (%s) speed %d MB/s\n",
               crypto_ahash_alg_name(tfm), crypto_ahash_driver_name(tfm),


@@ -119,7 +128,9 @@ static int cfs_crypto_hash_alloc(enum cfs_crypto_hash_alg hash_alg,
 
        err = crypto_ahash_init(*req);
        if (err) {
 
        err = crypto_ahash_init(*req);
        if (err) {

+out_free_req:

                ahash_request_free(*req);
                ahash_request_free(*req);

+out_free_tfm:

                crypto_free_ahash(tfm);
        }
        return err;
                crypto_free_ahash(tfm);
        }
        return err;