[CRYPTO] digest: Add alignment handling
Some hash modules load/store data words directly. The digest layer
should pass properly aligned buffer to update()/final() method. This
patch also add cra_alignmask to some hash modules.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/digest.c b/crypto/digest.c
index d9b6ac9..062d0a5 100644
--- a/crypto/digest.c
+++ b/crypto/digest.c
@@ -27,6 +27,7 @@
struct scatterlist *sg, unsigned int nsg)
{
unsigned int i;
+ unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
for (i = 0; i < nsg; i++) {
@@ -38,12 +39,24 @@
unsigned int bytes_from_page = min(l, ((unsigned int)
(PAGE_SIZE)) -
offset);
- char *p = crypto_kmap(pg, 0) + offset;
+ char *src = crypto_kmap(pg, 0);
+ char *p = src + offset;
+ if (unlikely(offset & alignmask)) {
+ unsigned int bytes =
+ alignmask + 1 - (offset & alignmask);
+ bytes = min(bytes, bytes_from_page);
+ tfm->__crt_alg->cra_digest.dia_update
+ (crypto_tfm_ctx(tfm), p,
+ bytes);
+ p += bytes;
+ bytes_from_page -= bytes;
+ l -= bytes;
+ }
tfm->__crt_alg->cra_digest.dia_update
(crypto_tfm_ctx(tfm), p,
bytes_from_page);
- crypto_kunmap(p, 0);
+ crypto_kunmap(src, 0);
crypto_yield(tfm);
offset = 0;
pg++;
@@ -54,7 +67,15 @@
static void final(struct crypto_tfm *tfm, u8 *out)
{
- tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), out);
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ if (unlikely((unsigned long)out & alignmask)) {
+ unsigned int size = crypto_tfm_alg_digestsize(tfm);
+ u8 buffer[size + alignmask];
+ u8 *dst = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), dst);
+ memcpy(out, dst, size);
+ } else
+ tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), out);
}
static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
@@ -69,18 +90,9 @@
static void digest(struct crypto_tfm *tfm,
struct scatterlist *sg, unsigned int nsg, u8 *out)
{
- unsigned int i;
-
- tfm->crt_digest.dit_init(tfm);
-
- for (i = 0; i < nsg; i++) {
- char *p = crypto_kmap(sg[i].page, 0) + sg[i].offset;
- tfm->__crt_alg->cra_digest.dia_update(crypto_tfm_ctx(tfm),
- p, sg[i].length);
- crypto_kunmap(p, 0);
- crypto_yield(tfm);
- }
- crypto_digest_final(tfm, out);
+ init(tfm);
+ update(tfm, sg, nsg);
+ final(tfm, out);
}
int crypto_init_digest_flags(struct crypto_tfm *tfm, u32 flags)