2007-05-19 09:45:22

by Sebastian Andrzej Siewior

Subject: [Patch] [CRYPTO] add alignment for setkey() (rev 3)

setkey() in {cipher,blkcipher,ablkcipher,hash}.c does not respect the
requested alignment by the algorithm. This patch fixes it. The extra
memory is allocated by kmalloc() with GFP_ATOMIC flag.

Signed-off-by: Sebastian Siewior <[email protected]>
Index: crypto-2.6/crypto/cipher.c
===================================================================
--- crypto-2.6.orig/crypto/cipher.c
+++ crypto-2.6/crypto/cipher.c
@@ -20,16 +20,43 @@
#include <linux/string.h>
#include "internal.h"

+static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
+{
+ struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = cia->cia_setkey(tfm, alignbuffer, keylen);
+ memset(alignbuffer, 0, absize);
+ kfree(buffer);
+ return ret;
+
+}
+
static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
{
struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
-
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+
tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) {
tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
- } else
- return cia->cia_setkey(tfm, key, keylen);
+ }
+
+ if ((unsigned long)key & alignmask)
+ return setkey_unaligned(tfm, key, keylen);
+
+ return cia->cia_setkey(tfm, key, keylen);
}

static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
Index: crypto-2.6/crypto/ablkcipher.c
===================================================================
--- crypto-2.6.orig/crypto/ablkcipher.c
+++ crypto-2.6/crypto/ablkcipher.c
@@ -19,16 +19,41 @@
#include <linux/module.h>
#include <linux/seq_file.h>

+static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key, unsigned int keylen)
+{
+ struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
+ unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = cipher->setkey(tfm, alignbuffer, keylen);
+ memset(alignbuffer, 0, absize);
+ kfree(buffer);
+ return ret;
+}
+
static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
unsigned int keylen)
{
struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
+ unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);

if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
return -EINVAL;
}

+ if ((unsigned long)key & alignmask)
+ return setkey_unaligned(tfm, key, keylen);
+
return cipher->setkey(tfm, key, keylen);
}

Index: crypto-2.6/crypto/blkcipher.c
===================================================================
--- crypto-2.6.orig/crypto/blkcipher.c
+++ crypto-2.6/crypto/blkcipher.c
@@ -336,16 +336,41 @@ static int blkcipher_walk_first(struct b
return blkcipher_walk_next(desc, walk);
}

+static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
+{
+ struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = cipher->setkey(tfm, alignbuffer, keylen);
+ memset(alignbuffer, 0, absize);
+ kfree(buffer);
+ return ret;
+}
+
static int setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int keylen)
{
struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);

if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}

+ if ((unsigned long)key & alignmask)
+ return setkey_unaligned(tfm, key, keylen);
+
return cipher->setkey(tfm, key, keylen);
}

Index: crypto-2.6/crypto/hash.c
===================================================================
--- crypto-2.6.orig/crypto/hash.c
+++ crypto-2.6/crypto/hash.c
@@ -22,6 +22,42 @@ static unsigned int crypto_hash_ctxsize(
return alg->cra_ctxsize;
}

+static int hash_setkey_unaligned(struct crypto_hash *crt, const u8 *key,
+ unsigned int keylen)
+{
+ struct crypto_tfm *tfm = crypto_hash_tfm(crt);
+ struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
+ unsigned long alignmask = crypto_hash_alignmask(crt);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = alg->setkey(crt, alignbuffer, keylen);
+ memset(alignbuffer, 0, absize);
+ kfree(buffer);
+ return ret;
+}
+
+static int hash_setkey(struct crypto_hash *crt, const u8 *key,
+ unsigned int keylen)
+{
+ struct crypto_tfm *tfm = crypto_hash_tfm(crt);
+ struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
+ unsigned long alignmask = crypto_hash_alignmask(crt);
+
+ if ((unsigned long)key & alignmask)
+ return hash_setkey_unaligned(crt, key, keylen);
+
+ return alg->setkey(crt, key, keylen);
+}
+
static int crypto_init_hash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
{
struct hash_tfm *crt = &tfm->crt_hash;
@@ -34,7 +70,7 @@ static int crypto_init_hash_ops(struct c
crt->update = alg->update;
crt->final = alg->final;
crt->digest = alg->digest;
- crt->setkey = alg->setkey;
+ crt->setkey = hash_setkey;
crt->digestsize = alg->digestsize;

return 0;

2007-05-19 09:51:42

by Herbert Xu

Subject: Re: [Patch] [CRYPTO] add alignment for setkey() (rev 3)

On Sat, May 19, 2007 at 11:45:18AM +0200, Sebastian Siewior wrote:
> setkey() in {cipher,blkcipher,ablkcipher,hash}.c does not respect the
> requested alignment by the algorithm. This patch fixes it. The extra
> memory is allocated by kmalloc() with GFP_ATOMIC flag.
>
> Signed-off-by: Sebastian Siewior <[email protected]>

Patch applied. Thanks a lot!
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