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authorHerbert Xu <herbert@gondor.apana.org.au>2007-11-20 20:32:56 +0800
committerHerbert Xu <herbert@gondor.apana.org.au>2008-01-11 08:16:20 +1100
commit3f8214ea335e422702340d7e835921e78367f99d (patch)
treeef8b7ef5c7e2d079e05e2a048db22eb183498235 /crypto/ctr.c
parentd0b9007a27206fe944d9db72e13dab157b8e118c (diff)
downloadlinux-stericsson-3f8214ea335e422702340d7e835921e78367f99d.tar.gz
[CRYPTO] ctr: Use crypto_inc and crypto_xor
This patch replaces the custom inc/xor in CTR with the generic functions. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/ctr.c')
-rw-r--r--crypto/ctr.c71
1 files changed, 16 insertions, 55 deletions
diff --git a/crypto/ctr.c b/crypto/ctr.c
index b974a9f9b879..b816e959fa55 100644
--- a/crypto/ctr.c
+++ b/crypto/ctr.c
@@ -31,51 +31,6 @@ struct crypto_ctr_ctx {
u8 *nonce;
};
-static inline void __ctr_inc_byte(u8 *a, unsigned int size)
-{
- u8 *b = (a + size);
- u8 c;
-
- for (; size; size--) {
- c = *--b + 1;
- *b = c;
- if (c)
- break;
- }
-}
-
-static void ctr_inc_quad(u8 *a, unsigned int size)
-{
- __be32 *b = (__be32 *)(a + size);
- u32 c;
-
- for (; size >= 4; size -=4) {
- c = be32_to_cpu(*--b) + 1;
- *b = cpu_to_be32(c);
- if (c)
- return;
- }
-
- __ctr_inc_byte(a, size);
-}
-
-static void xor_byte(u8 *a, const u8 *b, unsigned int bs)
-{
- for (; bs; bs--)
- *a++ ^= *b++;
-}
-
-static void xor_quad(u8 *dst, const u8 *src, unsigned int bs)
-{
- u32 *a = (u32 *)dst;
- u32 *b = (u32 *)src;
-
- for (; bs >= 4; bs -= 4)
- *a++ ^= *b++;
-
- xor_byte((u8 *)a, (u8 *)b, bs);
-}
-
static int crypto_ctr_setkey(struct crypto_tfm *parent, const u8 *key,
unsigned int keylen)
{
@@ -111,7 +66,8 @@ static int crypto_ctr_crypt_segment(struct blkcipher_walk *walk,
void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
crypto_cipher_alg(tfm)->cia_encrypt;
unsigned int bsize = crypto_cipher_blocksize(tfm);
- unsigned long alignmask = crypto_cipher_alignmask(tfm);
+ unsigned long alignmask = crypto_cipher_alignmask(tfm) |
+ (__alignof__(u32) - 1);
u8 ks[bsize + alignmask];
u8 *keystream = (u8 *)ALIGN((unsigned long)ks, alignmask + 1);
u8 *src = walk->src.virt.addr;
@@ -121,13 +77,13 @@ static int crypto_ctr_crypt_segment(struct blkcipher_walk *walk,
do {
/* create keystream */
fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
- xor_quad(keystream, src, min(nbytes, bsize));
+ crypto_xor(keystream, src, min(nbytes, bsize));
/* copy result into dst */
memcpy(dst, keystream, min(nbytes, bsize));
/* increment counter in counterblock */
- ctr_inc_quad(ctrblk + (bsize - countersize), countersize);
+ crypto_inc(ctrblk + bsize - countersize, countersize);
if (nbytes < bsize)
break;
@@ -148,7 +104,8 @@ static int crypto_ctr_crypt_inplace(struct blkcipher_walk *walk,
void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
crypto_cipher_alg(tfm)->cia_encrypt;
unsigned int bsize = crypto_cipher_blocksize(tfm);
- unsigned long alignmask = crypto_cipher_alignmask(tfm);
+ unsigned long alignmask = crypto_cipher_alignmask(tfm) |
+ (__alignof__(u32) - 1);
unsigned int nbytes = walk->nbytes;
u8 *src = walk->src.virt.addr;
u8 ks[bsize + alignmask];
@@ -157,10 +114,10 @@ static int crypto_ctr_crypt_inplace(struct blkcipher_walk *walk,
do {
/* create keystream */
fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
- xor_quad(src, keystream, min(nbytes, bsize));
+ crypto_xor(src, keystream, min(nbytes, bsize));
/* increment counter in counterblock */
- ctr_inc_quad(ctrblk + (bsize - countersize), countersize);
+ crypto_inc(ctrblk + bsize - countersize, countersize);
if (nbytes < bsize)
break;
@@ -184,7 +141,8 @@ static int crypto_ctr_crypt(struct blkcipher_desc *desc,
unsigned int bsize = crypto_cipher_blocksize(child);
struct ctr_instance_ctx *ictx =
crypto_instance_ctx(crypto_tfm_alg_instance(&tfm->base));
- unsigned long alignmask = crypto_cipher_alignmask(child);
+ unsigned long alignmask = crypto_cipher_alignmask(child) |
+ (__alignof__(u32) - 1);
u8 cblk[bsize + alignmask];
u8 *counterblk = (u8 *)ALIGN((unsigned long)cblk, alignmask + 1);
int err;
@@ -198,8 +156,7 @@ static int crypto_ctr_crypt(struct blkcipher_desc *desc,
memcpy(counterblk + ictx->noncesize, walk.iv, ictx->ivsize);
/* initialize counter portion of counter block */
- ctr_inc_quad(counterblk + (bsize - ictx->countersize),
- ictx->countersize);
+ crypto_inc(counterblk + bsize - ictx->countersize, ictx->countersize);
while (walk.nbytes) {
if (walk.src.virt.addr == walk.dst.virt.addr)
@@ -284,6 +241,10 @@ static struct crypto_instance *crypto_ctr_alloc(struct rtattr **tb)
(countersize > alg->cra_blocksize) || (countersize < 4))
goto out_put_alg;
+ /* If this is false we'd fail the alignment of crypto_inc. */
+ if ((alg->cra_blocksize - countersize) % 4)
+ goto out_put_alg;
+
inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
err = -ENOMEM;
if (!inst)
@@ -316,7 +277,7 @@ static struct crypto_instance *crypto_ctr_alloc(struct rtattr **tb)
inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
inst->alg.cra_priority = alg->cra_priority;
inst->alg.cra_blocksize = 1;
- inst->alg.cra_alignmask = 3;
+ inst->alg.cra_alignmask = __alignof__(u32) - 1;
inst->alg.cra_type = &crypto_blkcipher_type;
inst->alg.cra_blkcipher.ivsize = ivsize;