diff mbox series

[5/9] crypto: camellia - use unaligned accessors instead of alignmask

Message ID 20210201180237.3171-6-ardb@kernel.org (mailing list archive)
State Accepted
Delegated to: Herbert Xu
Headers show
Series crypto: fix alignmask handling | expand

Commit Message

Ard Biesheuvel Feb. 1, 2021, 6:02 p.m. UTC
Instead of using an alignmask of 0x3 to ensure 32-bit alignment of the
Camellia input and output blocks, which propagates to mode drivers, and
results in pointless copying on architectures that don't care about
alignment, use the unaligned accessors, which will do the right thing on
each respective architecture, avoiding the need for double buffering.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 crypto/camellia_generic.c | 45 +++++++-------------
 1 file changed, 16 insertions(+), 29 deletions(-)
diff mbox series

Patch

diff --git a/crypto/camellia_generic.c b/crypto/camellia_generic.c
index 0b9f409f7370..fd1a88af9e77 100644
--- a/crypto/camellia_generic.c
+++ b/crypto/camellia_generic.c
@@ -9,14 +9,6 @@ 
  *  https://info.isl.ntt.co.jp/crypt/eng/camellia/specifications.html
  */
 
-/*
- *
- * NOTE --- NOTE --- NOTE --- NOTE
- * This implementation assumes that all memory addresses passed
- * as parameters are four-byte aligned.
- *
- */
-
 #include <linux/crypto.h>
 #include <linux/errno.h>
 #include <linux/init.h>
@@ -994,16 +986,14 @@  camellia_set_key(struct crypto_tfm *tfm, const u8 *in_key,
 static void camellia_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	const struct camellia_ctx *cctx = crypto_tfm_ctx(tfm);
-	const __be32 *src = (const __be32 *)in;
-	__be32 *dst = (__be32 *)out;
 	unsigned int max;
 
 	u32 tmp[4];
 
-	tmp[0] = be32_to_cpu(src[0]);
-	tmp[1] = be32_to_cpu(src[1]);
-	tmp[2] = be32_to_cpu(src[2]);
-	tmp[3] = be32_to_cpu(src[3]);
+	tmp[0] = get_unaligned_be32(in);
+	tmp[1] = get_unaligned_be32(in + 4);
+	tmp[2] = get_unaligned_be32(in + 8);
+	tmp[3] = get_unaligned_be32(in + 12);
 
 	if (cctx->key_length == 16)
 		max = 24;
@@ -1013,25 +1003,23 @@  static void camellia_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 	camellia_do_encrypt(cctx->key_table, tmp, max);
 
 	/* do_encrypt returns 0,1 swapped with 2,3 */
-	dst[0] = cpu_to_be32(tmp[2]);
-	dst[1] = cpu_to_be32(tmp[3]);
-	dst[2] = cpu_to_be32(tmp[0]);
-	dst[3] = cpu_to_be32(tmp[1]);
+	put_unaligned_be32(tmp[2], out);
+	put_unaligned_be32(tmp[3], out + 4);
+	put_unaligned_be32(tmp[0], out + 8);
+	put_unaligned_be32(tmp[1], out + 12);
 }
 
 static void camellia_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	const struct camellia_ctx *cctx = crypto_tfm_ctx(tfm);
-	const __be32 *src = (const __be32 *)in;
-	__be32 *dst = (__be32 *)out;
 	unsigned int max;
 
 	u32 tmp[4];
 
-	tmp[0] = be32_to_cpu(src[0]);
-	tmp[1] = be32_to_cpu(src[1]);
-	tmp[2] = be32_to_cpu(src[2]);
-	tmp[3] = be32_to_cpu(src[3]);
+	tmp[0] = get_unaligned_be32(in);
+	tmp[1] = get_unaligned_be32(in + 4);
+	tmp[2] = get_unaligned_be32(in + 8);
+	tmp[3] = get_unaligned_be32(in + 12);
 
 	if (cctx->key_length == 16)
 		max = 24;
@@ -1041,10 +1029,10 @@  static void camellia_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 	camellia_do_decrypt(cctx->key_table, tmp, max);
 
 	/* do_decrypt returns 0,1 swapped with 2,3 */
-	dst[0] = cpu_to_be32(tmp[2]);
-	dst[1] = cpu_to_be32(tmp[3]);
-	dst[2] = cpu_to_be32(tmp[0]);
-	dst[3] = cpu_to_be32(tmp[1]);
+	put_unaligned_be32(tmp[2], out);
+	put_unaligned_be32(tmp[3], out + 4);
+	put_unaligned_be32(tmp[0], out + 8);
+	put_unaligned_be32(tmp[1], out + 12);
 }
 
 static struct crypto_alg camellia_alg = {
@@ -1054,7 +1042,6 @@  static struct crypto_alg camellia_alg = {
 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
 	.cra_blocksize		=	CAMELLIA_BLOCK_SIZE,
 	.cra_ctxsize		=	sizeof(struct camellia_ctx),
-	.cra_alignmask		=	3,
 	.cra_module		=	THIS_MODULE,
 	.cra_u			=	{
 		.cipher = {