* Cipher operations.
*
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* any later version.
*
*/
-#include <linux/compiler.h>
+
#include <linux/kernel.h>
#include <linux/crypto.h>
#include <linux/errno.h>
-#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/string.h>
-#include <asm/scatterlist.h>
#include "internal.h"
-#include "scatterwalk.h"
-
-typedef void (cryptfn_t)(void *, u8 *, const u8 *);
-typedef void (procfn_t)(struct crypto_tfm *, u8 *,
- u8*, cryptfn_t, void *);
-
-static inline void xor_64(u8 *a, const u8 *b)
-{
- ((u32 *)a)[0] ^= ((u32 *)b)[0];
- ((u32 *)a)[1] ^= ((u32 *)b)[1];
-}
-
-static inline void xor_128(u8 *a, const u8 *b)
-{
- ((u32 *)a)[0] ^= ((u32 *)b)[0];
- ((u32 *)a)[1] ^= ((u32 *)b)[1];
- ((u32 *)a)[2] ^= ((u32 *)b)[2];
- ((u32 *)a)[3] ^= ((u32 *)b)[3];
-}
-
-static inline void *prepare_src(struct scatter_walk *walk, int bsize,
- void *tmp, int in_place)
-{
- void *src = walk->data;
- int n = bsize;
-
- if (unlikely(scatterwalk_across_pages(walk, bsize))) {
- src = tmp;
- n = scatterwalk_copychunks(src, walk, bsize, 0);
- }
- scatterwalk_advance(walk, n);
- return src;
-}
-
-static inline void *prepare_dst(struct scatter_walk *walk, int bsize,
- void *tmp, int in_place)
-{
- void *dst = walk->data;
-
- if (unlikely(scatterwalk_across_pages(walk, bsize)) || in_place)
- dst = tmp;
- return dst;
-}
-
-static inline void complete_src(struct scatter_walk *walk, int bsize,
- void *src, int in_place)
-{
-}
-
-static inline void complete_dst(struct scatter_walk *walk, int bsize,
- void *dst, int in_place)
-{
- int n = bsize;
-
- if (unlikely(scatterwalk_across_pages(walk, bsize)))
- n = scatterwalk_copychunks(dst, walk, bsize, 1);
- else if (in_place)
- memcpy(walk->data, dst, bsize);
- scatterwalk_advance(walk, n);
-}
-
-/*
- * Generic encrypt/decrypt wrapper for ciphers, handles operations across
- * multiple page boundaries by using temporary blocks. In user context,
- * the kernel is given a chance to schedule us once per block.
- */
-static int crypt(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes, cryptfn_t crfn,
- procfn_t prfn, void *info)
-{
- struct scatter_walk walk_in, walk_out;
- const unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
- u8 tmp_src[bsize];
- u8 tmp_dst[bsize];
-
- if (!nbytes)
- return 0;
-
- if (nbytes % bsize) {
- tfm->crt_flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
- return -EINVAL;
- }
-
- scatterwalk_start(&walk_in, src);
- scatterwalk_start(&walk_out, dst);
-
- for(;;) {
- u8 *src_p, *dst_p;
- int in_place;
-
- scatterwalk_map(&walk_in, 0);
- scatterwalk_map(&walk_out, 1);
-
- in_place = scatterwalk_samebuf(&walk_in, &walk_out);
-
- do {
- src_p = prepare_src(&walk_in, bsize, tmp_src,
- in_place);
- dst_p = prepare_dst(&walk_out, bsize, tmp_dst,
- in_place);
-
- prfn(tfm, dst_p, src_p, crfn, info);
-
- complete_src(&walk_in, bsize, src_p, in_place);
- complete_dst(&walk_out, bsize, dst_p, in_place);
-
- nbytes -= bsize;
- } while (nbytes &&
- !scatterwalk_across_pages(&walk_in, bsize) &&
- !scatterwalk_across_pages(&walk_out, bsize));
- scatterwalk_done(&walk_in, 0, nbytes);
- scatterwalk_done(&walk_out, 1, nbytes);
-
- if (!nbytes)
- return 0;
-
- crypto_yield(tfm);
- }
-}
-
-static void cbc_process_encrypt(struct crypto_tfm *tfm, u8 *dst, u8 *src,
- cryptfn_t fn, void *info)
+static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int keylen)
{
- u8 *iv = info;
-
- tfm->crt_u.cipher.cit_xor_block(iv, src);
- fn(crypto_tfm_ctx(tfm), dst, iv);
- memcpy(iv, dst, crypto_tfm_alg_blocksize(tfm));
-}
-
-static void cbc_process_decrypt(struct crypto_tfm *tfm, u8 *dst, u8 *src,
- cryptfn_t fn, void *info)
-{
- u8 *iv = info;
-
- fn(crypto_tfm_ctx(tfm), dst, src);
- tfm->crt_u.cipher.cit_xor_block(dst, iv);
- memcpy(iv, src, crypto_tfm_alg_blocksize(tfm));
-}
+ 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, keylen);
+ kfree(buffer);
+ return ret;
-static void ecb_process(struct crypto_tfm *tfm, u8 *dst, u8 *src,
- cryptfn_t fn, void *info)
-{
- fn(crypto_tfm_ctx(tfm), dst, src);
}
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(crypto_tfm_ctx(tfm), key, keylen,
- &tfm->crt_flags);
-}
+ }
-static int ecb_encrypt(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src, unsigned int nbytes)
-{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_encrypt,
- ecb_process, NULL);
-}
+ if ((unsigned long)key & alignmask)
+ return setkey_unaligned(tfm, key, keylen);
-static int ecb_decrypt(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes)
-{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_decrypt,
- ecb_process, NULL);
+ return cia->cia_setkey(tfm, key, keylen);
}
-static int cbc_encrypt(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes)
+static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
+ const u8 *),
+ struct crypto_tfm *tfm,
+ u8 *dst, const u8 *src)
{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_encrypt,
- cbc_process_encrypt, tfm->crt_cipher.cit_iv);
-}
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ unsigned int size = crypto_tfm_alg_blocksize(tfm);
+ u8 buffer[size + alignmask];
+ u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
-static int cbc_encrypt_iv(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes, u8 *iv)
-{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_encrypt,
- cbc_process_encrypt, iv);
+ memcpy(tmp, src, size);
+ fn(tfm, tmp, tmp);
+ memcpy(dst, tmp, size);
}
-static int cbc_decrypt(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes)
+static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
+ u8 *dst, const u8 *src)
{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_decrypt,
- cbc_process_decrypt, tfm->crt_cipher.cit_iv);
-}
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
-static int cbc_decrypt_iv(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes, u8 *iv)
-{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_decrypt,
- cbc_process_decrypt, iv);
-}
+ if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
+ cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
+ return;
+ }
-static int nocrypt(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes)
-{
- return -ENOSYS;
+ cipher->cia_encrypt(tfm, dst, src);
}
-static int nocrypt_iv(struct crypto_tfm *tfm,
- struct scatterlist *dst,
- struct scatterlist *src,
- unsigned int nbytes, u8 *iv)
+static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
+ u8 *dst, const u8 *src)
{
- return -ENOSYS;
-}
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
-int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags)
-{
- u32 mode = flags & CRYPTO_TFM_MODE_MASK;
-
- tfm->crt_cipher.cit_mode = mode ? mode : CRYPTO_TFM_MODE_ECB;
- if (flags & CRYPTO_TFM_REQ_WEAK_KEY)
- tfm->crt_flags = CRYPTO_TFM_REQ_WEAK_KEY;
-
- return 0;
+ if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
+ cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
+ return;
+ }
+
+ cipher->cia_decrypt(tfm, dst, src);
}
int crypto_init_cipher_ops(struct crypto_tfm *tfm)
{
- int ret = 0;
struct cipher_tfm *ops = &tfm->crt_cipher;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
ops->cit_setkey = setkey;
+ ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
+ cipher_encrypt_unaligned : cipher->cia_encrypt;
+ ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
+ cipher_decrypt_unaligned : cipher->cia_decrypt;
- switch (tfm->crt_cipher.cit_mode) {
- case CRYPTO_TFM_MODE_ECB:
- ops->cit_encrypt = ecb_encrypt;
- ops->cit_decrypt = ecb_decrypt;
- break;
-
- case CRYPTO_TFM_MODE_CBC:
- ops->cit_encrypt = cbc_encrypt;
- ops->cit_decrypt = cbc_decrypt;
- ops->cit_encrypt_iv = cbc_encrypt_iv;
- ops->cit_decrypt_iv = cbc_decrypt_iv;
- break;
-
- case CRYPTO_TFM_MODE_CFB:
- ops->cit_encrypt = nocrypt;
- ops->cit_decrypt = nocrypt;
- ops->cit_encrypt_iv = nocrypt_iv;
- ops->cit_decrypt_iv = nocrypt_iv;
- break;
-
- case CRYPTO_TFM_MODE_CTR:
- ops->cit_encrypt = nocrypt;
- ops->cit_decrypt = nocrypt;
- ops->cit_encrypt_iv = nocrypt_iv;
- ops->cit_decrypt_iv = nocrypt_iv;
- break;
-
- default:
- BUG();
- }
-
- if (ops->cit_mode == CRYPTO_TFM_MODE_CBC) {
-
- switch (crypto_tfm_alg_blocksize(tfm)) {
- case 8:
- ops->cit_xor_block = xor_64;
- break;
-
- case 16:
- ops->cit_xor_block = xor_128;
- break;
-
- default:
- printk(KERN_WARNING "%s: block size %u not supported\n",
- crypto_tfm_alg_name(tfm),
- crypto_tfm_alg_blocksize(tfm));
- ret = -EINVAL;
- goto out;
- }
-
- ops->cit_ivsize = crypto_tfm_alg_blocksize(tfm);
- ops->cit_iv = kmalloc(ops->cit_ivsize, GFP_KERNEL);
- if (ops->cit_iv == NULL)
- ret = -ENOMEM;
- }
-
-out:
- return ret;
+ return 0;
}
void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
{
- if (tfm->crt_cipher.cit_iv)
- kfree(tfm->crt_cipher.cit_iv);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff