[net-next-2.6.git] / crypto / cipher.c

/*
 * Cryptographic API.
 *
 * 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
 * Software Foundation; either version 2 of the License, or (at your option) 
 * 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"

struct cipher_alg_compat {
	unsigned int cia_min_keysize;
	unsigned int cia_max_keysize;
	int (*cia_setkey)(struct crypto_tfm *tfm, const u8 *key,
	                  unsigned int keylen);
	void (*cia_encrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
	void (*cia_decrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);

	unsigned int (*cia_encrypt_ecb)(const struct cipher_desc *desc,
					u8 *dst, const u8 *src,
					unsigned int nbytes);
	unsigned int (*cia_decrypt_ecb)(const struct cipher_desc *desc,
					u8 *dst, const u8 *src,
					unsigned int nbytes);
	unsigned int (*cia_encrypt_cbc)(const struct cipher_desc *desc,
					u8 *dst, const u8 *src,
					unsigned int nbytes);
	unsigned int (*cia_decrypt_cbc)(const struct cipher_desc *desc,
					u8 *dst, const u8 *src,
					unsigned int nbytes);
};

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 unsigned int crypt_slow(const struct cipher_desc *desc,
			       struct scatter_walk *in,
			       struct scatter_walk *out, unsigned int 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;

	scatterwalk_copychunks(src, in, bsize, 0);
	desc->prfn(desc, dst, src, bsize);
	scatterwalk_copychunks(dst, out, bsize, 1);

	return bsize;
}

static inline unsigned int crypt_fast(const struct cipher_desc *desc,
				      struct scatter_walk *in,
				      struct scatter_walk *out,
				      unsigned int nbytes, u8 *tmp)
{
	u8 *src, *dst;
	u8 *real_src, *real_dst;

	real_src = scatterwalk_map(in, 0);
	real_dst = scatterwalk_map(out, 1);

	src = real_src;
	dst = scatterwalk_samebuf(in, out) ? src : real_dst;

	if (tmp) {
		memcpy(tmp, src, nbytes);
		src = tmp;
		dst = tmp;
	}

	nbytes = desc->prfn(desc, dst, src, nbytes);

	if (tmp)
		memcpy(real_dst, tmp, nbytes);

	scatterwalk_unmap(real_src, 0);
	scatterwalk_unmap(real_dst, 1);

	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 page.
 */
static int crypt(const struct cipher_desc *desc,
		 struct scatterlist *dst,
		 struct scatterlist *src,
		 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);
	unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
	unsigned long buffer = 0;

	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(;;) {
		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;
		}

		n = scatterwalk_clamp(&walk_in, n);
		n = scatterwalk_clamp(&walk_out, n);

		if (likely(n >= bsize))
			n = crypt_fast(desc, &walk_in, &walk_out, n, tmp);
		else
			n = crypt_slow(desc, &walk_in, &walk_out, bsize);

		nbytes -= n;

		scatterwalk_done(&walk_in, 0, nbytes);
		scatterwalk_done(&walk_out, 1, nbytes);

		if (!nbytes)
			break;

		crypto_yield(tfm->crt_flags);
	}

	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 unsigned int cbc_process_encrypt(const struct cipher_desc *desc,
					u8 *dst, const u8 *src,
					unsigned int nbytes)
{
	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);

	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn;
	u8 *iv = desc->info;
	unsigned int done = 0;

	nbytes -= bsize;

	do {
		xor(iv, src);
		fn(tfm, dst, iv);
		memcpy(iv, dst, bsize);

		src += bsize;
		dst += bsize;
	} while ((done += bsize) <= nbytes);

	return done;
}

static unsigned int cbc_process_decrypt(const struct cipher_desc *desc,
					u8 *dst, const u8 *src,
					unsigned int nbytes)
{
	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)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn;
	u8 *iv = desc->info;
	unsigned int done = 0;

	nbytes -= bsize;

	do {
		u8 *tmp_dst = *dst_p;

		fn(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 unsigned int ecb_process(const struct cipher_desc *desc, u8 *dst,
				const u8 *src, unsigned int nbytes)
{
	struct crypto_tfm *tfm = desc->tfm;
	int bsize = crypto_tfm_alg_blocksize(tfm);
	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn;
	unsigned int done = 0;

	nbytes -= bsize;

	do {
		fn(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 cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	
	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);
}

static int ecb_encrypt(struct crypto_tfm *tfm,
		       struct scatterlist *dst,
                       struct scatterlist *src, unsigned int nbytes)
{
	struct cipher_desc desc;
	struct cipher_alg_compat *cipher = (void *)&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 *dst,
                       struct scatterlist *src,
		       unsigned int nbytes)
{
	struct cipher_desc desc;
	struct cipher_alg_compat *cipher = (void *)&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 *dst,
                       struct scatterlist *src,
		       unsigned int nbytes)
{
	struct cipher_desc desc;
	struct cipher_alg_compat *cipher = (void *)&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 *dst,
                          struct scatterlist *src,
                          unsigned int nbytes, u8 *iv)
{
	struct cipher_desc desc;
	struct cipher_alg_compat *cipher = (void *)&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 *dst,
                       struct scatterlist *src,
		       unsigned int nbytes)
{
	struct cipher_desc desc;
	struct cipher_alg_compat *cipher = (void *)&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 *dst,
                          struct scatterlist *src,
                          unsigned int nbytes, u8 *iv)
{
	struct cipher_desc desc;
	struct cipher_alg_compat *cipher = (void *)&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,
                   struct scatterlist *dst,
                   struct scatterlist *src,
		   unsigned int nbytes)
{
	return -ENOSYS;
}

static int nocrypt_iv(struct crypto_tfm *tfm,
                      struct scatterlist *dst,
                      struct scatterlist *src,
                      unsigned int nbytes, u8 *iv)
{
	return -ENOSYS;
}

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;
	return 0;
}

static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
					      const u8 *),
				   struct crypto_tfm *tfm,
				   u8 *dst, const u8 *src)
{
	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);

	memcpy(tmp, src, size);
	fn(tfm, tmp, tmp);
	memcpy(dst, tmp, size);
}

static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
				     u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
		cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
		return;
	}

	cipher->cia_encrypt(tfm, dst, src);
}

static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
				     u8 *dst, const u8 *src)
{
	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;

	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;
		ops->cit_encrypt_iv = nocrypt_iv;
		ops->cit_decrypt_iv = nocrypt_iv;
		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) {
		unsigned long align;
		unsigned long addr;
	    	
	    	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);
		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:	
	return ret;
}

void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
{
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Cryptographic API.
	3	*
	4	* Cipher operations.
	5	*
	6	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
c774e93e	7	* Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4 LT	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
	11	* Software Foundation; either version 2 of the License, or (at your option)
	12	* any later version.
	13	*
	14	*/
	15	#include <linux/compiler.h>
	16	#include <linux/kernel.h>
	17	#include <linux/crypto.h>
	18	#include <linux/errno.h>
	19	#include <linux/mm.h>
	20	#include <linux/slab.h>
	21	#include <linux/string.h>
	22	#include <asm/scatterlist.h>
	23	#include "internal.h"
	24	#include "scatterwalk.h"
	25
7226bc87 HX	26	struct cipher_alg_compat {
	27	unsigned int cia_min_keysize;
	28	unsigned int cia_max_keysize;
	29	int (cia_setkey)(struct crypto_tfm tfm, const u8 *key,
	30	unsigned int keylen);
	31	void (cia_encrypt)(struct crypto_tfm tfm, u8 dst, const u8 src);
	32	void (cia_decrypt)(struct crypto_tfm tfm, u8 dst, const u8 src);
	33
	34	unsigned int (cia_encrypt_ecb)(const struct cipher_desc desc,
	35	u8 dst, const u8 src,
	36	unsigned int nbytes);
	37	unsigned int (cia_decrypt_ecb)(const struct cipher_desc desc,
	38	u8 dst, const u8 src,
	39	unsigned int nbytes);
	40	unsigned int (cia_encrypt_cbc)(const struct cipher_desc desc,
	41	u8 dst, const u8 src,
	42	unsigned int nbytes);
	43	unsigned int (cia_decrypt_cbc)(const struct cipher_desc desc,
	44	u8 dst, const u8 src,
	45	unsigned int nbytes);
	46	};
	47
1da177e4 LT	48	static inline void xor_64(u8 a, const u8 b)
	49	{
	50	((u32 )a)[0] ^= ((u32 )b)[0];
	51	((u32 )a)[1] ^= ((u32 )b)[1];
	52	}
	53
	54	static inline void xor_128(u8 a, const u8 b)
	55	{
	56	((u32 )a)[0] ^= ((u32 )b)[0];
	57	((u32 )a)[1] ^= ((u32 )b)[1];
	58	((u32 )a)[2] ^= ((u32 )b)[2];
	59	((u32 )a)[3] ^= ((u32 )b)[3];
	60	}
c774e93e HX	61
	62	static unsigned int crypt_slow(const struct cipher_desc *desc,
	63	struct scatter_walk *in,
	64	struct scatter_walk *out, unsigned int bsize)
1da177e4	65	{
9d853c37	66	unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm);
95477377 HX	67	u8 buffer[bsize * 2 + alignmask];
	68	u8 src = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	69	u8 *dst = src + bsize;
1da177e4	70
5c64097a	71	scatterwalk_copychunks(src, in, bsize, 0);
c774e93e	72	desc->prfn(desc, dst, src, bsize);
5c64097a	73	scatterwalk_copychunks(dst, out, bsize, 1);
1da177e4	74
c774e93e	75	return bsize;
1da177e4 LT	76	}
1da177e4 LT	77
c774e93e HX	78	static inline unsigned int crypt_fast(const struct cipher_desc *desc,
	79	struct scatter_walk *in,
	80	struct scatter_walk *out,
95477377	81	unsigned int nbytes, u8 *tmp)
1da177e4	82	{
c774e93e	83	u8 src, dst;
5c64097a HX	84	u8 real_src, real_dst;
	85
	86	real_src = scatterwalk_map(in, 0);
	87	real_dst = scatterwalk_map(out, 1);
c774e93e	88
5c64097a HX	89	src = real_src;
5c64097a HX	90	dst = scatterwalk_samebuf(in, out) ? src : real_dst;
c774e93e	91
95477377	92	if (tmp) {
5c64097a	93	memcpy(tmp, src, nbytes);
95477377 HX	94	src = tmp;
	95	dst = tmp;
	96	}
	97
c774e93e HX	98	nbytes = desc->prfn(desc, dst, src, nbytes);
c774e93e HX	99
95477377	100	if (tmp)
5c64097a HX	101	memcpy(real_dst, tmp, nbytes);
	102
	103	scatterwalk_unmap(real_src, 0);
	104	scatterwalk_unmap(real_dst, 1);
95477377	105
c774e93e HX	106	scatterwalk_advance(in, nbytes);
c774e93e HX	107	scatterwalk_advance(out, nbytes);
1da177e4	108
c774e93e	109	return nbytes;
1da177e4 LT	110	}
	111
	112	/*
	113	* Generic encrypt/decrypt wrapper for ciphers, handles operations across
	114	* multiple page boundaries by using temporary blocks. In user context,
c774e93e	115	* the kernel is given a chance to schedule us once per page.
1da177e4	116	*/
c774e93e	117	static int crypt(const struct cipher_desc *desc,
1da177e4 LT	118	struct scatterlist *dst,
1da177e4 LT	119	struct scatterlist *src,
c774e93e	120	unsigned int nbytes)
1da177e4 LT	121	{
1da177e4 LT	122	struct scatter_walk walk_in, walk_out;
c774e93e	123	struct crypto_tfm *tfm = desc->tfm;
1da177e4	124	const unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
fbdae9f3	125	unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
95477377	126	unsigned long buffer = 0;
1da177e4 LT	127
	128	if (!nbytes)
	129	return 0;
	130
	131	if (nbytes % bsize) {
	132	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
	133	return -EINVAL;
	134	}
	135
	136	scatterwalk_start(&walk_in, src);
	137	scatterwalk_start(&walk_out, dst);
	138
	139	for(;;) {
95477377 HX	140	unsigned int n = nbytes;
	141	u8 *tmp = NULL;
	142
	143	if (!scatterwalk_aligned(&walk_in, alignmask) \|\|
	144	!scatterwalk_aligned(&walk_out, alignmask)) {
	145	if (!buffer) {
	146	buffer = __get_free_page(GFP_ATOMIC);
	147	if (!buffer)
	148	n = 0;
	149	}
	150	tmp = (u8 *)buffer;
	151	}
1da177e4	152
95477377	153	n = scatterwalk_clamp(&walk_in, n);
c774e93e	154	n = scatterwalk_clamp(&walk_out, n);
1da177e4	155
c774e93e	156	if (likely(n >= bsize))
95477377	157	n = crypt_fast(desc, &walk_in, &walk_out, n, tmp);
c774e93e HX	158	else
c774e93e HX	159	n = crypt_slow(desc, &walk_in, &walk_out, bsize);
1da177e4	160
c774e93e	161	nbytes -= n;
1da177e4 LT	162
	163	scatterwalk_done(&walk_in, 0, nbytes);
	164	scatterwalk_done(&walk_out, 1, nbytes);
	165
	166	if (!nbytes)
95477377	167	break;
1da177e4	168
8f21cf0d	169	crypto_yield(tfm->crt_flags);
1da177e4	170	}
95477377 HX	171
	172	if (buffer)
	173	free_page(buffer);
	174
	175	return 0;
1da177e4 LT	176	}
1da177e4 LT	177
915e8561 HX	178	static int crypt_iv_unaligned(struct cipher_desc *desc,
	179	struct scatterlist *dst,
	180	struct scatterlist *src,
	181	unsigned int nbytes)
	182	{
	183	struct crypto_tfm *tfm = desc->tfm;
9d853c37	184	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
915e8561 HX	185	u8 *iv = desc->info;
	186
	187	if (unlikely(((unsigned long)iv & alignmask))) {
	188	unsigned int ivsize = tfm->crt_cipher.cit_ivsize;
	189	u8 buffer[ivsize + alignmask];
	190	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	191	int err;
	192
	193	desc->info = memcpy(tmp, iv, ivsize);
	194	err = crypt(desc, dst, src, nbytes);
	195	memcpy(iv, tmp, ivsize);
	196
	197	return err;
	198	}
	199
	200	return crypt(desc, dst, src, nbytes);
	201	}
	202
c774e93e HX	203	static unsigned int cbc_process_encrypt(const struct cipher_desc *desc,
	204	u8 dst, const u8 src,
	205	unsigned int nbytes)
1da177e4	206	{
c774e93e HX	207	struct crypto_tfm *tfm = desc->tfm;
	208	void (xor)(u8 , const u8 *) = tfm->crt_u.cipher.cit_xor_block;
	209	int bsize = crypto_tfm_alg_blocksize(tfm);
	210
6c2bb98b	211	void (fn)(struct crypto_tfm , u8 , const u8 ) = desc->crfn;
c774e93e HX	212	u8 *iv = desc->info;
	213	unsigned int done = 0;
	214
fe2d5295 HX	215	nbytes -= bsize;
fe2d5295 HX	216
c774e93e HX	217	do {
c774e93e HX	218	xor(iv, src);
6c2bb98b	219	fn(tfm, dst, iv);
c774e93e	220	memcpy(iv, dst, bsize);
1da177e4	221
c774e93e HX	222	src += bsize;
c774e93e HX	223	dst += bsize;
fe2d5295	224	} while ((done += bsize) <= nbytes);
c774e93e HX	225
c774e93e HX	226	return done;
1da177e4 LT	227	}
1da177e4 LT	228
c774e93e HX	229	static unsigned int cbc_process_decrypt(const struct cipher_desc *desc,
	230	u8 dst, const u8 src,
	231	unsigned int nbytes)
1da177e4	232	{
c774e93e HX	233	struct crypto_tfm *tfm = desc->tfm;
	234	void (xor)(u8 , const u8 *) = tfm->crt_u.cipher.cit_xor_block;
	235	int bsize = crypto_tfm_alg_blocksize(tfm);
827c3911	236	unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm);
c774e93e	237
827c3911 HX	238	u8 stack[src == dst ? bsize + alignmask : 0];
827c3911 HX	239	u8 buf = (u8 )ALIGN((unsigned long)stack, alignmask + 1);
c774e93e HX	240	u8 **dst_p = src == dst ? &buf : &dst;
c774e93e HX	241
6c2bb98b	242	void (fn)(struct crypto_tfm , u8 , const u8 ) = desc->crfn;
c774e93e HX	243	u8 *iv = desc->info;
	244	unsigned int done = 0;
	245
fe2d5295 HX	246	nbytes -= bsize;
fe2d5295 HX	247
c774e93e HX	248	do {
c774e93e HX	249	u8 tmp_dst = dst_p;
1da177e4	250
6c2bb98b	251	fn(tfm, tmp_dst, src);
c774e93e HX	252	xor(tmp_dst, iv);
	253	memcpy(iv, src, bsize);
	254	if (tmp_dst != dst)
	255	memcpy(dst, tmp_dst, bsize);
	256
	257	src += bsize;
	258	dst += bsize;
fe2d5295	259	} while ((done += bsize) <= nbytes);
c774e93e HX	260
c774e93e HX	261	return done;
1da177e4 LT	262	}
1da177e4 LT	263
c774e93e HX	264	static unsigned int ecb_process(const struct cipher_desc desc, u8 dst,
c774e93e HX	265	const u8 *src, unsigned int nbytes)
1da177e4	266	{
c774e93e HX	267	struct crypto_tfm *tfm = desc->tfm;
c774e93e HX	268	int bsize = crypto_tfm_alg_blocksize(tfm);
6c2bb98b	269	void (fn)(struct crypto_tfm , u8 , const u8 ) = desc->crfn;
c774e93e HX	270	unsigned int done = 0;
c774e93e HX	271
fe2d5295 HX	272	nbytes -= bsize;
fe2d5295 HX	273
c774e93e	274	do {
6c2bb98b	275	fn(tfm, dst, src);
c774e93e HX	276
	277	src += bsize;
	278	dst += bsize;
fe2d5295	279	} while ((done += bsize) <= nbytes);
c774e93e HX	280
c774e93e HX	281	return done;
1da177e4 LT	282	}
	283
	284	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
	285	{
	286	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	287
560c06ae	288	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
1da177e4 LT	289	if (keylen < cia->cia_min_keysize \|\| keylen > cia->cia_max_keysize) {
	290	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	291	return -EINVAL;
	292	} else
560c06ae	293	return cia->cia_setkey(tfm, key, keylen);
1da177e4 LT	294	}
	295
	296	static int ecb_encrypt(struct crypto_tfm *tfm,
	297	struct scatterlist *dst,
	298	struct scatterlist *src, unsigned int nbytes)
	299	{
c774e93e	300	struct cipher_desc desc;
7226bc87	301	struct cipher_alg_compat cipher = (void )&tfm->__crt_alg->cra_cipher;
c774e93e HX	302
c774e93e HX	303	desc.tfm = tfm;
40725181 HX	304	desc.crfn = cipher->cia_encrypt;
40725181 HX	305	desc.prfn = cipher->cia_encrypt_ecb ?: ecb_process;
c774e93e HX	306
c774e93e HX	307	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	308	}
	309
	310	static int ecb_decrypt(struct crypto_tfm *tfm,
	311	struct scatterlist *dst,
	312	struct scatterlist *src,
	313	unsigned int nbytes)
	314	{
c774e93e	315	struct cipher_desc desc;
7226bc87	316	struct cipher_alg_compat cipher = (void )&tfm->__crt_alg->cra_cipher;
c774e93e HX	317
c774e93e HX	318	desc.tfm = tfm;
40725181 HX	319	desc.crfn = cipher->cia_decrypt;
40725181 HX	320	desc.prfn = cipher->cia_decrypt_ecb ?: ecb_process;
c774e93e HX	321
c774e93e HX	322	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	323	}
	324
	325	static int cbc_encrypt(struct crypto_tfm *tfm,
	326	struct scatterlist *dst,
	327	struct scatterlist *src,
	328	unsigned int nbytes)
	329	{
c774e93e	330	struct cipher_desc desc;
7226bc87	331	struct cipher_alg_compat cipher = (void )&tfm->__crt_alg->cra_cipher;
c774e93e HX	332
c774e93e HX	333	desc.tfm = tfm;
40725181 HX	334	desc.crfn = cipher->cia_encrypt;
40725181 HX	335	desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
c774e93e HX	336	desc.info = tfm->crt_cipher.cit_iv;
	337
	338	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	339	}
	340
	341	static int cbc_encrypt_iv(struct crypto_tfm *tfm,
	342	struct scatterlist *dst,
	343	struct scatterlist *src,
	344	unsigned int nbytes, u8 *iv)
	345	{
c774e93e	346	struct cipher_desc desc;
7226bc87	347	struct cipher_alg_compat cipher = (void )&tfm->__crt_alg->cra_cipher;
c774e93e HX	348
c774e93e HX	349	desc.tfm = tfm;
40725181 HX	350	desc.crfn = cipher->cia_encrypt;
40725181 HX	351	desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
c774e93e HX	352	desc.info = iv;
c774e93e HX	353
915e8561	354	return crypt_iv_unaligned(&desc, dst, src, nbytes);
1da177e4 LT	355	}
	356
	357	static int cbc_decrypt(struct crypto_tfm *tfm,
	358	struct scatterlist *dst,
	359	struct scatterlist *src,
	360	unsigned int nbytes)
	361	{
c774e93e	362	struct cipher_desc desc;
7226bc87	363	struct cipher_alg_compat cipher = (void )&tfm->__crt_alg->cra_cipher;
c774e93e HX	364
c774e93e HX	365	desc.tfm = tfm;
40725181 HX	366	desc.crfn = cipher->cia_decrypt;
40725181 HX	367	desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
c774e93e HX	368	desc.info = tfm->crt_cipher.cit_iv;
	369
	370	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	371	}
	372
	373	static int cbc_decrypt_iv(struct crypto_tfm *tfm,
	374	struct scatterlist *dst,
	375	struct scatterlist *src,
	376	unsigned int nbytes, u8 *iv)
	377	{
c774e93e	378	struct cipher_desc desc;
7226bc87	379	struct cipher_alg_compat cipher = (void )&tfm->__crt_alg->cra_cipher;
c774e93e HX	380
c774e93e HX	381	desc.tfm = tfm;
40725181 HX	382	desc.crfn = cipher->cia_decrypt;
40725181 HX	383	desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
c774e93e HX	384	desc.info = iv;
c774e93e HX	385
915e8561	386	return crypt_iv_unaligned(&desc, dst, src, nbytes);
1da177e4 LT	387	}
	388
	389	static int nocrypt(struct crypto_tfm *tfm,
	390	struct scatterlist *dst,
	391	struct scatterlist *src,
	392	unsigned int nbytes)
	393	{
	394	return -ENOSYS;
	395	}
	396
	397	static int nocrypt_iv(struct crypto_tfm *tfm,
	398	struct scatterlist *dst,
	399	struct scatterlist *src,
	400	unsigned int nbytes, u8 *iv)
	401	{
	402	return -ENOSYS;
	403	}
	404
	405	int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags)
	406	{
	407	u32 mode = flags & CRYPTO_TFM_MODE_MASK;
1da177e4	408	tfm->crt_cipher.cit_mode = mode ? mode : CRYPTO_TFM_MODE_ECB;
1da177e4 LT	409	return 0;
	410	}
	411
f28776a3 HX	412	static void cipher_crypt_unaligned(void (fn)(struct crypto_tfm , u8 *,
	413	const u8 *),
	414	struct crypto_tfm *tfm,
	415	u8 dst, const u8 src)
	416	{
	417	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	418	unsigned int size = crypto_tfm_alg_blocksize(tfm);
	419	u8 buffer[size + alignmask];
	420	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	421
	422	memcpy(tmp, src, size);
	423	fn(tfm, tmp, tmp);
	424	memcpy(dst, tmp, size);
	425	}
	426
	427	static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
	428	u8 dst, const u8 src)
	429	{
	430	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	431	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	432
	433	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	434	cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
	435	return;
	436	}
	437
	438	cipher->cia_encrypt(tfm, dst, src);
	439	}
	440
	441	static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
	442	u8 dst, const u8 src)
	443	{
	444	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
	445	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
	446
	447	if (unlikely(((unsigned long)dst \| (unsigned long)src) & alignmask)) {
	448	cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
	449	return;
	450	}
	451
	452	cipher->cia_decrypt(tfm, dst, src);
	453	}
	454
1da177e4 LT	455	int crypto_init_cipher_ops(struct crypto_tfm *tfm)
	456	{
	457	int ret = 0;
	458	struct cipher_tfm *ops = &tfm->crt_cipher;
f28776a3	459	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
1da177e4 LT	460
1da177e4 LT	461	ops->cit_setkey = setkey;
f28776a3 HX	462	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	463	cipher_encrypt_unaligned : cipher->cia_encrypt;
	464	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
	465	cipher_decrypt_unaligned : cipher->cia_decrypt;
1da177e4 LT	466
	467	switch (tfm->crt_cipher.cit_mode) {
	468	case CRYPTO_TFM_MODE_ECB:
	469	ops->cit_encrypt = ecb_encrypt;
	470	ops->cit_decrypt = ecb_decrypt;
df89820e HX	471	ops->cit_encrypt_iv = nocrypt_iv;
df89820e HX	472	ops->cit_decrypt_iv = nocrypt_iv;
1da177e4 LT	473	break;
	474
	475	case CRYPTO_TFM_MODE_CBC:
	476	ops->cit_encrypt = cbc_encrypt;
	477	ops->cit_decrypt = cbc_decrypt;
	478	ops->cit_encrypt_iv = cbc_encrypt_iv;
	479	ops->cit_decrypt_iv = cbc_decrypt_iv;
	480	break;
	481
	482	case CRYPTO_TFM_MODE_CFB:
	483	ops->cit_encrypt = nocrypt;
	484	ops->cit_decrypt = nocrypt;
	485	ops->cit_encrypt_iv = nocrypt_iv;
	486	ops->cit_decrypt_iv = nocrypt_iv;
	487	break;
	488
	489	case CRYPTO_TFM_MODE_CTR:
	490	ops->cit_encrypt = nocrypt;
	491	ops->cit_decrypt = nocrypt;
	492	ops->cit_encrypt_iv = nocrypt_iv;
	493	ops->cit_decrypt_iv = nocrypt_iv;
	494	break;
	495
	496	default:
	497	BUG();
	498	}
	499
	500	if (ops->cit_mode == CRYPTO_TFM_MODE_CBC) {
9d853c37	501	unsigned long align;
fbdae9f3	502	unsigned long addr;
1da177e4 LT	503
	504	switch (crypto_tfm_alg_blocksize(tfm)) {
	505	case 8:
	506	ops->cit_xor_block = xor_64;
	507	break;
	508
	509	case 16:
	510	ops->cit_xor_block = xor_128;
	511	break;
	512
	513	default:
	514	printk(KERN_WARNING "%s: block size %u not supported\n",
	515	crypto_tfm_alg_name(tfm),
	516	crypto_tfm_alg_blocksize(tfm));
	517	ret = -EINVAL;
	518	goto out;
	519	}
	520
	521	ops->cit_ivsize = crypto_tfm_alg_blocksize(tfm);
fbdae9f3 HX	522	align = crypto_tfm_alg_alignmask(tfm) + 1;
	523	addr = (unsigned long)crypto_tfm_ctx(tfm);
	524	addr = ALIGN(addr, align);
	525	addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
	526	ops->cit_iv = (void *)addr;
1da177e4 LT	527	}
	528
	529	out:
	530	return ret;
	531	}
	532
	533	void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
	534	{
1da177e4	535	}