crypto: algif_aead - use memcpy_sglist() instead of null skcipher

For copying data between two scatterlists, just use memcpy_sglist()
instead of the so-called "null skcipher".  This is much simpler.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 7bfad077f3084c93b82bd65cb86f037eb1b563c7..551eeeab3a0a6ac7ff54060d8a871b2f4712a1e0 100644 (file)
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1392,7 +1392,6 @@ config CRYPTO_USER_API_AEAD
        depends on NET
        select CRYPTO_AEAD
        select CRYPTO_SKCIPHER
-       select CRYPTO_NULL
        select CRYPTO_USER_API
        help
          Enable the userspace interface for AEAD cipher algorithms.

diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index 7d58cbbce4af28bbaec153ca31feabe0345df516..79b016a899a1ef70c0252db6aad68723966041d2 100644 (file)
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -27,7 +27,6 @@
 #include <crypto/scatterwalk.h>
 #include <crypto/if_alg.h>
 #include <crypto/skcipher.h>
-#include <crypto/null.h>
 #include <linux/init.h>
 #include <linux/list.h>
 #include <linux/kernel.h>
@@ -36,19 +35,13 @@
 #include <linux/net.h>
 #include <net/sock.h>
 
-struct aead_tfm {
-       struct crypto_aead *aead;
-       struct crypto_sync_skcipher *null_tfm;
-};
-
 static inline bool aead_sufficient_data(struct sock *sk)
 {
        struct alg_sock *ask = alg_sk(sk);
        struct sock *psk = ask->parent;
        struct alg_sock *pask = alg_sk(psk);
        struct af_alg_ctx *ctx = ask->private;
-       struct aead_tfm *aeadc = pask->private;
-       struct crypto_aead *tfm = aeadc->aead;
+       struct crypto_aead *tfm = pask->private;
        unsigned int as = crypto_aead_authsize(tfm);
 
        /*
@@ -64,27 +57,12 @@ static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
        struct alg_sock *ask = alg_sk(sk);
        struct sock *psk = ask->parent;
        struct alg_sock *pask = alg_sk(psk);
-       struct aead_tfm *aeadc = pask->private;
-       struct crypto_aead *tfm = aeadc->aead;
+       struct crypto_aead *tfm = pask->private;
        unsigned int ivsize = crypto_aead_ivsize(tfm);
 
        return af_alg_sendmsg(sock, msg, size, ivsize);
 }
 
-static int crypto_aead_copy_sgl(struct crypto_sync_skcipher *null_tfm,
-                               struct scatterlist *src,
-                               struct scatterlist *dst, unsigned int len)
-{
-       SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, null_tfm);
-
-       skcipher_request_set_sync_tfm(skreq, null_tfm);
-       skcipher_request_set_callback(skreq, CRYPTO_TFM_REQ_MAY_SLEEP,
-                                     NULL, NULL);
-       skcipher_request_set_crypt(skreq, src, dst, len, NULL);
-
-       return crypto_skcipher_encrypt(skreq);
-}
-
 static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
                         size_t ignored, int flags)
 {
@@ -93,9 +71,7 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
        struct sock *psk = ask->parent;
        struct alg_sock *pask = alg_sk(psk);
        struct af_alg_ctx *ctx = ask->private;
-       struct aead_tfm *aeadc = pask->private;
-       struct crypto_aead *tfm = aeadc->aead;
-       struct crypto_sync_skcipher *null_tfm = aeadc->null_tfm;
+       struct crypto_aead *tfm = pask->private;
        unsigned int i, as = crypto_aead_authsize(tfm);
        struct af_alg_async_req *areq;
        struct af_alg_tsgl *tsgl, *tmp;
@@ -223,11 +199,8 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
                 *          v      v
                 * RX SGL: AAD || PT || Tag
                 */
-               err = crypto_aead_copy_sgl(null_tfm, tsgl_src,
-                                          areq->first_rsgl.sgl.sgt.sgl,
-                                          processed);
-               if (err)
-                       goto free;
+               memcpy_sglist(areq->first_rsgl.sgl.sgt.sgl, tsgl_src,
+                             processed);
                af_alg_pull_tsgl(sk, processed, NULL, 0);
        } else {
                /*
@@ -241,12 +214,8 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
                 * RX SGL: AAD || CT ----+
                 */
 
-                /* Copy AAD || CT to RX SGL buffer for in-place operation. */
-               err = crypto_aead_copy_sgl(null_tfm, tsgl_src,
-                                          areq->first_rsgl.sgl.sgt.sgl,
-                                          outlen);
-               if (err)
-                       goto free;
+               /* Copy AAD || CT to RX SGL buffer for in-place operation. */
+               memcpy_sglist(areq->first_rsgl.sgl.sgt.sgl, tsgl_src, outlen);
 
                /* Create TX SGL for tag and chain it to RX SGL. */
                areq->tsgl_entries = af_alg_count_tsgl(sk, processed,
@@ -379,7 +348,7 @@ static int aead_check_key(struct socket *sock)
        int err = 0;
        struct sock *psk;
        struct alg_sock *pask;
-       struct aead_tfm *tfm;
+       struct crypto_aead *tfm;
        struct sock *sk = sock->sk;
        struct alg_sock *ask = alg_sk(sk);
 
@@ -393,7 +362,7 @@ static int aead_check_key(struct socket *sock)
 
        err = -ENOKEY;
        lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
-       if (crypto_aead_get_flags(tfm->aead) & CRYPTO_TFM_NEED_KEY)
+       if (crypto_aead_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
                goto unlock;
 
        atomic_dec(&pask->nokey_refcnt);
@@ -454,54 +423,22 @@ static struct proto_ops algif_aead_ops_nokey = {
 
 static void *aead_bind(const char *name, u32 type, u32 mask)
 {
-       struct aead_tfm *tfm;
-       struct crypto_aead *aead;
-       struct crypto_sync_skcipher *null_tfm;
-
-       tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
-       if (!tfm)
-               return ERR_PTR(-ENOMEM);
-
-       aead = crypto_alloc_aead(name, type, mask);
-       if (IS_ERR(aead)) {
-               kfree(tfm);
-               return ERR_CAST(aead);
-       }
-
-       null_tfm = crypto_get_default_null_skcipher();
-       if (IS_ERR(null_tfm)) {
-               crypto_free_aead(aead);
-               kfree(tfm);
-               return ERR_CAST(null_tfm);
-       }
-
-       tfm->aead = aead;
-       tfm->null_tfm = null_tfm;
-
-       return tfm;
+       return crypto_alloc_aead(name, type, mask);
 }
 
 static void aead_release(void *private)
 {
-       struct aead_tfm *tfm = private;
-
-       crypto_free_aead(tfm->aead);
-       crypto_put_default_null_skcipher();
-       kfree(tfm);
+       crypto_free_aead(private);
 }
 
 static int aead_setauthsize(void *private, unsigned int authsize)
 {
-       struct aead_tfm *tfm = private;
-
-       return crypto_aead_setauthsize(tfm->aead, authsize);
+       return crypto_aead_setauthsize(private, authsize);
 }
 
 static int aead_setkey(void *private, const u8 *key, unsigned int keylen)
 {
-       struct aead_tfm *tfm = private;
-
-       return crypto_aead_setkey(tfm->aead, key, keylen);
+       return crypto_aead_setkey(private, key, keylen);
 }
 
 static void aead_sock_destruct(struct sock *sk)
@@ -510,8 +447,7 @@ static void aead_sock_destruct(struct sock *sk)
        struct af_alg_ctx *ctx = ask->private;
        struct sock *psk = ask->parent;
        struct alg_sock *pask = alg_sk(psk);
-       struct aead_tfm *aeadc = pask->private;
-       struct crypto_aead *tfm = aeadc->aead;
+       struct crypto_aead *tfm = pask->private;
        unsigned int ivlen = crypto_aead_ivsize(tfm);
 
        af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
@@ -524,10 +460,9 @@ static int aead_accept_parent_nokey(void *private, struct sock *sk)
 {
        struct af_alg_ctx *ctx;
        struct alg_sock *ask = alg_sk(sk);
-       struct aead_tfm *tfm = private;
-       struct crypto_aead *aead = tfm->aead;
+       struct crypto_aead *tfm = private;
        unsigned int len = sizeof(*ctx);
-       unsigned int ivlen = crypto_aead_ivsize(aead);
+       unsigned int ivlen = crypto_aead_ivsize(tfm);
 
        ctx = sock_kmalloc(sk, len, GFP_KERNEL);
        if (!ctx)
@@ -554,9 +489,9 @@ static int aead_accept_parent_nokey(void *private, struct sock *sk)
 
 static int aead_accept_parent(void *private, struct sock *sk)
 {
-       struct aead_tfm *tfm = private;
+       struct crypto_aead *tfm = private;
 
-       if (crypto_aead_get_flags(tfm->aead) & CRYPTO_TFM_NEED_KEY)
+       if (crypto_aead_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
                return -ENOKEY;
 
        return aead_accept_parent_nokey(private, sk);