* 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
#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)[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)
+
+static unsigned int crypt_slow(const struct cipher_desc *desc,
+ struct scatter_walk *in,
+ struct scatter_walk *out, unsigned int bsize)
{
- void *src = walk->data;
- int n = bsize;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm);
+ u8 buffer[bsize * 2 + alignmask];
+ u8 *src = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ u8 *dst = src + bsize;
+ unsigned int n;
- if (unlikely(scatterwalk_across_pages(walk, bsize))) {
- src = tmp;
- n = scatterwalk_copychunks(src, walk, bsize, 0);
- }
- scatterwalk_advance(walk, n);
- return src;
+ n = scatterwalk_copychunks(src, in, bsize, 0);
+ scatterwalk_advance(in, n);
+
+ desc->prfn(desc, dst, src, bsize);
+
+ n = scatterwalk_copychunks(dst, out, bsize, 1);
+ scatterwalk_advance(out, n);
+
+ return bsize;
}
-static inline void *prepare_dst(struct scatter_walk *walk, int bsize,
- void *tmp, int in_place)
+static inline unsigned int crypt_fast(const struct cipher_desc *desc,
+ struct scatter_walk *in,
+ struct scatter_walk *out,
+ unsigned int nbytes, u8 *tmp)
{
- void *dst = walk->data;
+ u8 *src, *dst;
- if (unlikely(scatterwalk_across_pages(walk, bsize)) || in_place)
+ src = in->data;
+ dst = scatterwalk_samebuf(in, out) ? src : out->data;
+
+ if (tmp) {
+ memcpy(tmp, in->data, nbytes);
+ src = tmp;
dst = tmp;
- return dst;
-}
+ }
-static inline void complete_src(struct scatter_walk *walk, int bsize,
- void *src, int in_place)
-{
-}
+ nbytes = desc->prfn(desc, dst, src, nbytes);
-static inline void complete_dst(struct scatter_walk *walk, int bsize,
- void *dst, int in_place)
-{
- int n = bsize;
+ if (tmp)
+ memcpy(out->data, tmp, nbytes);
- 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);
+ scatterwalk_advance(in, nbytes);
+ scatterwalk_advance(out, nbytes);
+
+ return nbytes;
}
/*
* 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.
+ * the kernel is given a chance to schedule us once per page.
*/
-static int crypt(struct crypto_tfm *tfm,
+static int crypt(const struct cipher_desc *desc,
struct scatterlist *dst,
struct scatterlist *src,
- unsigned int nbytes, cryptfn_t crfn,
- procfn_t prfn, void *info)
+ unsigned int nbytes)
{
struct scatter_walk walk_in, walk_out;
+ struct crypto_tfm *tfm = desc->tfm;
const unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
- u8 tmp_src[bsize];
- u8 tmp_dst[bsize];
+ unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
+ unsigned long buffer = 0;
if (!nbytes)
return 0;
scatterwalk_start(&walk_out, dst);
for(;;) {
- u8 *src_p, *dst_p;
- int in_place;
+ unsigned int n = nbytes;
+ u8 *tmp = NULL;
+
+ if (!scatterwalk_aligned(&walk_in, alignmask) ||
+ !scatterwalk_aligned(&walk_out, alignmask)) {
+ if (!buffer) {
+ buffer = __get_free_page(GFP_ATOMIC);
+ if (!buffer)
+ n = 0;
+ }
+ tmp = (u8 *)buffer;
+ }
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);
+ n = scatterwalk_clamp(&walk_in, n);
+ n = scatterwalk_clamp(&walk_out, n);
- prfn(tfm, dst_p, src_p, crfn, info);
+ if (likely(n >= bsize))
+ n = crypt_fast(desc, &walk_in, &walk_out, n, tmp);
+ else
+ n = crypt_slow(desc, &walk_in, &walk_out, bsize);
- 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));
+ nbytes -= n;
scatterwalk_done(&walk_in, 0, nbytes);
scatterwalk_done(&walk_out, 1, nbytes);
if (!nbytes)
- return 0;
+ break;
crypto_yield(tfm);
}
+
+ if (buffer)
+ free_page(buffer);
+
+ return 0;
+}
+
+static int crypt_iv_unaligned(struct cipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ struct crypto_tfm *tfm = desc->tfm;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ u8 *iv = desc->info;
+
+ if (unlikely(((unsigned long)iv & alignmask))) {
+ unsigned int ivsize = tfm->crt_cipher.cit_ivsize;
+ u8 buffer[ivsize + alignmask];
+ u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ int err;
+
+ desc->info = memcpy(tmp, iv, ivsize);
+ err = crypt(desc, dst, src, nbytes);
+ memcpy(iv, tmp, ivsize);
+
+ return err;
+ }
+
+ return crypt(desc, dst, src, nbytes);
}
-static void cbc_process_encrypt(struct crypto_tfm *tfm, u8 *dst, u8 *src,
- cryptfn_t fn, void *info)
+static unsigned int cbc_process_encrypt(const struct cipher_desc *desc,
+ u8 *dst, const u8 *src,
+ unsigned int nbytes)
{
- u8 *iv = info;
+ struct crypto_tfm *tfm = desc->tfm;
+ void (*xor)(u8 *, const u8 *) = tfm->crt_u.cipher.cit_xor_block;
+ int bsize = crypto_tfm_alg_blocksize(tfm);
- tfm->crt_u.cipher.cit_xor_block(iv, src);
- fn(crypto_tfm_ctx(tfm), dst, iv);
- memcpy(iv, dst, crypto_tfm_alg_blocksize(tfm));
+ void (*fn)(void *, u8 *, const u8 *) = desc->crfn;
+ u8 *iv = desc->info;
+ unsigned int done = 0;
+
+ nbytes -= bsize;
+
+ do {
+ xor(iv, src);
+ fn(crypto_tfm_ctx(tfm), dst, iv);
+ memcpy(iv, dst, bsize);
+
+ src += bsize;
+ dst += bsize;
+ } while ((done += bsize) <= nbytes);
+
+ return done;
}
-static void cbc_process_decrypt(struct crypto_tfm *tfm, u8 *dst, u8 *src,
- cryptfn_t fn, void *info)
+static unsigned int cbc_process_decrypt(const struct cipher_desc *desc,
+ u8 *dst, const u8 *src,
+ unsigned int nbytes)
{
- u8 *iv = info;
+ struct crypto_tfm *tfm = desc->tfm;
+ void (*xor)(u8 *, const u8 *) = tfm->crt_u.cipher.cit_xor_block;
+ int bsize = crypto_tfm_alg_blocksize(tfm);
+ unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm);
+
+ u8 stack[src == dst ? bsize + alignmask : 0];
+ u8 *buf = (u8 *)ALIGN((unsigned long)stack, alignmask + 1);
+ u8 **dst_p = src == dst ? &buf : &dst;
+
+ void (*fn)(void *, u8 *, const u8 *) = desc->crfn;
+ u8 *iv = desc->info;
+ unsigned int done = 0;
+
+ nbytes -= bsize;
- fn(crypto_tfm_ctx(tfm), dst, src);
- tfm->crt_u.cipher.cit_xor_block(dst, iv);
- memcpy(iv, src, crypto_tfm_alg_blocksize(tfm));
+ do {
+ u8 *tmp_dst = *dst_p;
+
+ fn(crypto_tfm_ctx(tfm), tmp_dst, src);
+ xor(tmp_dst, iv);
+ memcpy(iv, src, bsize);
+ if (tmp_dst != dst)
+ memcpy(dst, tmp_dst, bsize);
+
+ src += bsize;
+ dst += bsize;
+ } while ((done += bsize) <= nbytes);
+
+ return done;
}
-static void ecb_process(struct crypto_tfm *tfm, u8 *dst, u8 *src,
- cryptfn_t fn, void *info)
+static unsigned int ecb_process(const struct cipher_desc *desc, u8 *dst,
+ const u8 *src, unsigned int nbytes)
{
- fn(crypto_tfm_ctx(tfm), dst, src);
+ struct crypto_tfm *tfm = desc->tfm;
+ int bsize = crypto_tfm_alg_blocksize(tfm);
+ void (*fn)(void *, u8 *, const u8 *) = desc->crfn;
+ unsigned int done = 0;
+
+ nbytes -= bsize;
+
+ do {
+ fn(crypto_tfm_ctx(tfm), dst, src);
+
+ src += bsize;
+ dst += bsize;
+ } while ((done += bsize) <= nbytes);
+
+ return done;
}
static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
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);
+ struct cipher_desc desc;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ desc.tfm = tfm;
+ desc.crfn = cipher->cia_encrypt;
+ desc.prfn = cipher->cia_encrypt_ecb ?: ecb_process;
+
+ return crypt(&desc, dst, src, nbytes);
}
static int ecb_decrypt(struct crypto_tfm *tfm,
struct scatterlist *src,
unsigned int nbytes)
{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_decrypt,
- ecb_process, NULL);
+ struct cipher_desc desc;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ desc.tfm = tfm;
+ desc.crfn = cipher->cia_decrypt;
+ desc.prfn = cipher->cia_decrypt_ecb ?: ecb_process;
+
+ return crypt(&desc, dst, src, nbytes);
}
static int cbc_encrypt(struct crypto_tfm *tfm,
struct scatterlist *src,
unsigned int nbytes)
{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_encrypt,
- cbc_process_encrypt, tfm->crt_cipher.cit_iv);
+ struct cipher_desc desc;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ desc.tfm = tfm;
+ desc.crfn = cipher->cia_encrypt;
+ desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
+ desc.info = tfm->crt_cipher.cit_iv;
+
+ return crypt(&desc, dst, src, nbytes);
}
static int cbc_encrypt_iv(struct crypto_tfm *tfm,
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);
+ struct cipher_desc desc;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ desc.tfm = tfm;
+ desc.crfn = cipher->cia_encrypt;
+ desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
+ desc.info = iv;
+
+ return crypt_iv_unaligned(&desc, dst, src, nbytes);
}
static int cbc_decrypt(struct crypto_tfm *tfm,
struct scatterlist *src,
unsigned int nbytes)
{
- return crypt(tfm, dst, src, nbytes,
- tfm->__crt_alg->cra_cipher.cia_decrypt,
- cbc_process_decrypt, tfm->crt_cipher.cit_iv);
+ struct cipher_desc desc;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ desc.tfm = tfm;
+ desc.crfn = cipher->cia_decrypt;
+ desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
+ desc.info = tfm->crt_cipher.cit_iv;
+
+ return crypt(&desc, dst, src, nbytes);
}
static int cbc_decrypt_iv(struct crypto_tfm *tfm,
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);
+ struct cipher_desc desc;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ desc.tfm = tfm;
+ desc.crfn = cipher->cia_decrypt;
+ desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
+ desc.info = iv;
+
+ return crypt_iv_unaligned(&desc, dst, src, nbytes);
}
static int nocrypt(struct crypto_tfm *tfm,
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 (ops->cit_mode == CRYPTO_TFM_MODE_CBC) {
+ unsigned long align;
+ unsigned long addr;
switch (crypto_tfm_alg_blocksize(tfm)) {
case 8:
}
ops->cit_ivsize = crypto_tfm_alg_blocksize(tfm);
- ops->cit_iv = kmalloc(ops->cit_ivsize, GFP_KERNEL);
- if (ops->cit_iv == NULL)
- ret = -ENOMEM;
+ align = crypto_tfm_alg_alignmask(tfm) + 1;
+ addr = (unsigned long)crypto_tfm_ctx(tfm);
+ addr = ALIGN(addr, align);
+ addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
+ ops->cit_iv = (void *)addr;
}
out:
void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
{
- if (tfm->crt_cipher.cit_iv)
- kfree(tfm->crt_cipher.cit_iv);
}
git://git.onelab.eu / linux-2.6.git / blobdiff