crypto: morus - fix handling chunked inputs
authorEric Biggers <ebiggers@google.com>
Fri, 1 Feb 2019 07:51:37 +0000 (23:51 -0800)
committerHerbert Xu <herbert@gondor.apana.org.au>
Fri, 8 Feb 2019 07:30:08 +0000 (15:30 +0800)
The generic MORUS implementations all fail the improved AEAD tests
because they produce the wrong result with some data layouts.  The issue
is that they assume that if the skcipher_walk API gives 'nbytes' not
aligned to the walksize (a.k.a. walk.stride), then it is the end of the
data.  In fact, this can happen before the end.  Fix them.

Fixes: 396be41f16fd ("crypto: morus - Add generic MORUS AEAD implementations")
Cc: <stable@vger.kernel.org> # v4.18+
Cc: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto/morus1280.c
crypto/morus640.c

index 78ba09db7328c79c0240aa8566e2f45d5c6856c7..0747732d5b78a6adb5b4f7bcafd3209ae4ebdbff 100644 (file)
@@ -362,18 +362,19 @@ static void crypto_morus1280_process_crypt(struct morus1280_state *state,
                                           const struct morus1280_ops *ops)
 {
        struct skcipher_walk walk;
-       u8 *dst;
-       const u8 *src;
 
        ops->skcipher_walk_init(&walk, req, false);
 
        while (walk.nbytes) {
-               src = walk.src.virt.addr;
-               dst = walk.dst.virt.addr;
+               unsigned int nbytes = walk.nbytes;
 
-               ops->crypt_chunk(state, dst, src, walk.nbytes);
+               if (nbytes < walk.total)
+                       nbytes = round_down(nbytes, walk.stride);
 
-               skcipher_walk_done(&walk, 0);
+               ops->crypt_chunk(state, walk.dst.virt.addr, walk.src.virt.addr,
+                                nbytes);
+
+               skcipher_walk_done(&walk, walk.nbytes - nbytes);
        }
 }
 
index 5cf530139b271fd1678a9ccce5a9bd14de76e8e9..1617a1eb8be13137007e043a38da34e9c6574105 100644 (file)
@@ -361,18 +361,19 @@ static void crypto_morus640_process_crypt(struct morus640_state *state,
                                          const struct morus640_ops *ops)
 {
        struct skcipher_walk walk;
-       u8 *dst;
-       const u8 *src;
 
        ops->skcipher_walk_init(&walk, req, false);
 
        while (walk.nbytes) {
-               src = walk.src.virt.addr;
-               dst = walk.dst.virt.addr;
+               unsigned int nbytes = walk.nbytes;
 
-               ops->crypt_chunk(state, dst, src, walk.nbytes);
+               if (nbytes < walk.total)
+                       nbytes = round_down(nbytes, walk.stride);
 
-               skcipher_walk_done(&walk, 0);
+               ops->crypt_chunk(state, walk.dst.virt.addr, walk.src.virt.addr,
+                                nbytes);
+
+               skcipher_walk_done(&walk, walk.nbytes - nbytes);
        }
 }