[CRYPTO] Handle unaligned iv from encrypt_iv/decrypt_iv
Even though cit_iv is now always aligned, the user can still supply an
unaligned iv through crypto_cipher_encrypt_iv/crypto_cipher_decrypt_iv.
This patch will check the alignment of the user-supplied iv and copy
it if necessary.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/crypto/cipher.c b/crypto/cipher.c
index d3295ce..1c92c6b 100644
--- a/crypto/cipher.c
+++ b/crypto/cipher.c
@@ -154,6 +154,31 @@
return 0;
}
+static int crypt_iv_unaligned(struct cipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ struct crypto_tfm *tfm = desc->tfm;
+ unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
+ u8 *iv = desc->info;
+
+ if (unlikely(((unsigned long)iv & alignmask))) {
+ unsigned int ivsize = tfm->crt_cipher.cit_ivsize;
+ u8 buffer[ivsize + alignmask];
+ u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ int err;
+
+ desc->info = memcpy(tmp, iv, ivsize);
+ err = crypt(desc, dst, src, nbytes);
+ memcpy(iv, tmp, ivsize);
+
+ return err;
+ }
+
+ return crypt(desc, dst, src, nbytes);
+}
+
static unsigned int cbc_process_encrypt(const struct cipher_desc *desc,
u8 *dst, const u8 *src,
unsigned int nbytes)
@@ -298,7 +323,7 @@
desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
desc.info = iv;
- return crypt(&desc, dst, src, nbytes);
+ return crypt_iv_unaligned(&desc, dst, src, nbytes);
}
static int cbc_decrypt(struct crypto_tfm *tfm,
@@ -330,7 +355,7 @@
desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
desc.info = iv;
- return crypt(&desc, dst, src, nbytes);
+ return crypt_iv_unaligned(&desc, dst, src, nbytes);
}
static int nocrypt(struct crypto_tfm *tfm,