1 files changed, 33 insertions, 31 deletions

diff --git a/crypto/ctr.c b/crypto/ctr.c
index b816e95..57da7d0 100644
--- a/crypto/ctr.c
+++ b/crypto/ctr.c
@@ -59,6 +59,21 @@ static int crypto_ctr_setkey(struct crypto_tfm *parent, const u8 *key,
 	return err;
 }
 
+static void crypto_ctr_crypt_final(struct blkcipher_walk *walk,
+				   struct crypto_cipher *tfm, u8 *ctrblk,
+				   unsigned int countersize)
+{
+	unsigned int bsize = crypto_cipher_blocksize(tfm);
+	u8 *keystream = ctrblk + bsize;
+	u8 *src = walk->src.virt.addr;
+	u8 *dst = walk->dst.virt.addr;
+	unsigned int nbytes = walk->nbytes;
+
+	crypto_cipher_encrypt_one(tfm, keystream, ctrblk);
+	crypto_xor(keystream, src, nbytes);
+	memcpy(dst, keystream, nbytes);
+}
+
 static int crypto_ctr_crypt_segment(struct blkcipher_walk *walk,
 				    struct crypto_cipher *tfm, u8 *ctrblk,
 				    unsigned int countersize)
@@ -66,35 +81,23 @@ 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) |
-				  (__alignof__(u32) - 1);
-	u8 ks[bsize + alignmask];
-	u8 *keystream = (u8 *)ALIGN((unsigned long)ks, alignmask + 1);
 	u8 *src = walk->src.virt.addr;
 	u8 *dst = walk->dst.virt.addr;
 	unsigned int nbytes = walk->nbytes;
 
 	do {
 		/* create keystream */
-		fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
-		crypto_xor(keystream, src, min(nbytes, bsize));
-
-		/* copy result into dst */
-		memcpy(dst, keystream, min(nbytes, bsize));
+		fn(crypto_cipher_tfm(tfm), dst, ctrblk);
+		crypto_xor(dst, src, bsize);
 
 		/* increment counter in counterblock */
 		crypto_inc(ctrblk + bsize - countersize, countersize);
 
-		if (nbytes < bsize)
-			break;
-
 		src += bsize;
 		dst += bsize;
-		nbytes -= bsize;
-
-	} while (nbytes);
+	} while ((nbytes -= bsize) >= bsize);
 
-	return 0;
+	return nbytes;
 }
 
 static int crypto_ctr_crypt_inplace(struct blkcipher_walk *walk,
@@ -104,30 +107,22 @@ 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) |
-				  (__alignof__(u32) - 1);
 	unsigned int nbytes = walk->nbytes;
 	u8 *src = walk->src.virt.addr;
-	u8 ks[bsize + alignmask];
-	u8 *keystream = (u8 *)ALIGN((unsigned long)ks, alignmask + 1);
+	u8 *keystream = ctrblk + bsize;
 
 	do {
 		/* create keystream */
 		fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
-		crypto_xor(src, keystream, min(nbytes, bsize));
+		crypto_xor(src, keystream, bsize);
 
 		/* increment counter in counterblock */
 		crypto_inc(ctrblk + bsize - countersize, countersize);
 
-		if (nbytes < bsize)
-			break;
-
 		src += bsize;
-		nbytes -= bsize;
+	} while ((nbytes -= bsize) >= bsize);
 
-	} while (nbytes);
-
-	return 0;
+	return nbytes;
 }
 
 static int crypto_ctr_crypt(struct blkcipher_desc *desc,
@@ -143,7 +138,7 @@ static int crypto_ctr_crypt(struct blkcipher_desc *desc,
 		crypto_instance_ctx(crypto_tfm_alg_instance(&tfm->base));
 	unsigned long alignmask = crypto_cipher_alignmask(child) |
 				  (__alignof__(u32) - 1);
-	u8 cblk[bsize + alignmask];
+	u8 cblk[bsize * 2 + alignmask];
 	u8 *counterblk = (u8 *)ALIGN((unsigned long)cblk, alignmask + 1);
 	int err;
 
@@ -158,7 +153,7 @@ static int crypto_ctr_crypt(struct blkcipher_desc *desc,
 	/* initialize counter portion of counter block */
 	crypto_inc(counterblk + bsize - ictx->countersize, ictx->countersize);
 
-	while (walk.nbytes) {
+	while (walk.nbytes >= bsize) {
 		if (walk.src.virt.addr == walk.dst.virt.addr)
 			nbytes = crypto_ctr_crypt_inplace(&walk, child,
 							  counterblk,
@@ -170,6 +165,13 @@ static int crypto_ctr_crypt(struct blkcipher_desc *desc,
 
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}
+
+	if (walk.nbytes) {
+		crypto_ctr_crypt_final(&walk, child, counterblk,
+				       ictx->countersize);
+		err = blkcipher_walk_done(desc, &walk, 0);
+	}
+
 	return err;
 }
 
@@ -277,7 +279,7 @@ 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 = __alignof__(u32) - 1;
+	inst->alg.cra_alignmask = alg->cra_alignmask | (__alignof__(u32) - 1);
 	inst->alg.cra_type = &crypto_blkcipher_type;
 
 	inst->alg.cra_blkcipher.ivsize = ivsize;