crypto: aegis - fix handling chunked inputs
authorEric Biggers <ebiggers@google.com>
Fri, 1 Feb 2019 07:51:36 +0000 (23:51 -0800)
committerHerbert Xu <herbert@gondor.apana.org.au>
Fri, 8 Feb 2019 07:30:08 +0000 (15:30 +0800)
The generic AEGIS 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: f606a88e5823 ("crypto: aegis - Add generic AEGIS 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/aegis128.c
crypto/aegis128l.c
crypto/aegis256.c

index 96e078a..3718a83 100644 (file)
@@ -286,19 +286,19 @@ static void crypto_aegis128_process_crypt(struct aegis_state *state,
                                          const struct aegis128_ops *ops)
 {
        struct skcipher_walk walk;
-       u8 *src, *dst;
-       unsigned int chunksize;
 
        ops->skcipher_walk_init(&walk, req, false);
 
        while (walk.nbytes) {
-               src = walk.src.virt.addr;
-               dst = walk.dst.virt.addr;
-               chunksize = walk.nbytes;
+               unsigned int nbytes = walk.nbytes;
 
-               ops->crypt_chunk(state, dst, src, chunksize);
+               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 a210e77..275a861 100644 (file)
@@ -349,19 +349,19 @@ static void crypto_aegis128l_process_crypt(struct aegis_state *state,
                                           const struct aegis128l_ops *ops)
 {
        struct skcipher_walk walk;
-       u8 *src, *dst;
-       unsigned int chunksize;
 
        ops->skcipher_walk_init(&walk, req, false);
 
        while (walk.nbytes) {
-               src = walk.src.virt.addr;
-               dst = walk.dst.virt.addr;
-               chunksize = walk.nbytes;
+               unsigned int nbytes = walk.nbytes;
 
-               ops->crypt_chunk(state, dst, src, chunksize);
+               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 49882a2..ecd6b7f 100644 (file)
@@ -299,19 +299,19 @@ static void crypto_aegis256_process_crypt(struct aegis_state *state,
                                          const struct aegis256_ops *ops)
 {
        struct skcipher_walk walk;
-       u8 *src, *dst;
-       unsigned int chunksize;
 
        ops->skcipher_walk_init(&walk, req, false);
 
        while (walk.nbytes) {
-               src = walk.src.virt.addr;
-               dst = walk.dst.virt.addr;
-               chunksize = walk.nbytes;
+               unsigned int nbytes = walk.nbytes;
 
-               ops->crypt_chunk(state, dst, src, chunksize);
+               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);
        }
 }