diff options
| -rw-r--r-- | crypto/ctr.c | 71 |
1 files changed, 16 insertions, 55 deletions
diff --git a/crypto/ctr.c b/crypto/ctr.c index b974a9f..b816e95 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; |
