[linux.git] / crypto / cipher.c

/*
 * Cryptographic API.
 *
 * Cipher operations.
 *
 * Copyright (c) 2002 James Morris <[email protected]>
 * Copyright (c) 2005 Herbert Xu <[email protected]>
 *
 * 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"

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 int 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;

	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 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;

	src = in->data;
	dst = scatterwalk_samebuf(in, out) ? src : out->data;

	if (tmp) {
		memcpy(tmp, in->data, nbytes);
		src = tmp;
		dst = tmp;
	}

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

	if (tmp)
		memcpy(out->data, tmp, nbytes);

	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;
		}

		scatterwalk_map(&walk_in, 0);
		scatterwalk_map(&walk_out, 1);

		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);
	}

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

	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 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);

	u8 stack[src == dst ? bsize : 0];
	u8 *buf = stack;
	u8 **dst_p = src == dst ? &buf : &dst;

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

	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 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)(void *, u8 *, const u8 *) = desc->crfn;
	unsigned int done = 0;

	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 cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	
	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)
{
	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 *dst,
                       struct scatterlist *src,
		       unsigned int nbytes)
{
	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 *dst,
                       struct scatterlist *src,
		       unsigned int nbytes)
{
	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 *dst,
                          struct scatterlist *src,
                          unsigned int nbytes, u8 *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 *dst,
                       struct scatterlist *src,
		       unsigned int nbytes)
{
	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 *dst,
                          struct scatterlist *src,
                          unsigned int nbytes, u8 *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,
                   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;
	if (flags & CRYPTO_TFM_REQ_WEAK_KEY)
		tfm->crt_flags = CRYPTO_TFM_REQ_WEAK_KEY;
	
	return 0;
}

int crypto_init_cipher_ops(struct crypto_tfm *tfm)
{
	int ret = 0;
	struct cipher_tfm *ops = &tfm->crt_cipher;

	ops->cit_setkey = setkey;

	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) {
		unsigned int 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 <[email protected]>
c774e93e	7	* Copyright (c) 2005 Herbert Xu <[email protected]>
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
1da177e4 LT	26	static inline void xor_64(u8 a, const u8 b)
	27	{
	28	((u32 )a)[0] ^= ((u32 )b)[0];
	29	((u32 )a)[1] ^= ((u32 )b)[1];
	30	}
	31
	32	static inline void xor_128(u8 a, const u8 b)
	33	{
	34	((u32 )a)[0] ^= ((u32 )b)[0];
	35	((u32 )a)[1] ^= ((u32 )b)[1];
	36	((u32 )a)[2] ^= ((u32 )b)[2];
	37	((u32 )a)[3] ^= ((u32 )b)[3];
	38	}
c774e93e HX	39
	40	static unsigned int crypt_slow(const struct cipher_desc *desc,
	41	struct scatter_walk *in,
	42	struct scatter_walk *out, unsigned int bsize)
1da177e4	43	{
fbdae9f3	44	unsigned int alignmask = crypto_tfm_alg_alignmask(desc->tfm);
95477377 HX	45	u8 buffer[bsize * 2 + alignmask];
	46	u8 src = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	47	u8 *dst = src + bsize;
c774e93e	48	unsigned int n;
1da177e4	49
c774e93e HX	50	n = scatterwalk_copychunks(src, in, bsize, 0);
c774e93e HX	51	scatterwalk_advance(in, n);
1da177e4	52
c774e93e	53	desc->prfn(desc, dst, src, bsize);
1da177e4	54
c774e93e HX	55	n = scatterwalk_copychunks(dst, out, bsize, 1);
c774e93e HX	56	scatterwalk_advance(out, n);
1da177e4	57
c774e93e	58	return bsize;
1da177e4 LT	59	}
1da177e4 LT	60
c774e93e HX	61	static inline unsigned int crypt_fast(const struct cipher_desc *desc,
	62	struct scatter_walk *in,
	63	struct scatter_walk *out,
95477377	64	unsigned int nbytes, u8 *tmp)
1da177e4	65	{
c774e93e HX	66	u8 src, dst;
	67
	68	src = in->data;
	69	dst = scatterwalk_samebuf(in, out) ? src : out->data;
	70
95477377 HX	71	if (tmp) {
	72	memcpy(tmp, in->data, nbytes);
	73	src = tmp;
	74	dst = tmp;
	75	}
	76
c774e93e HX	77	nbytes = desc->prfn(desc, dst, src, nbytes);
c774e93e HX	78
95477377 HX	79	if (tmp)
	80	memcpy(out->data, tmp, nbytes);
	81
c774e93e HX	82	scatterwalk_advance(in, nbytes);
c774e93e HX	83	scatterwalk_advance(out, nbytes);
1da177e4	84
c774e93e	85	return nbytes;
1da177e4 LT	86	}
	87
	88	/*
	89	* Generic encrypt/decrypt wrapper for ciphers, handles operations across
	90	* multiple page boundaries by using temporary blocks. In user context,
c774e93e	91	* the kernel is given a chance to schedule us once per page.
1da177e4	92	*/
c774e93e	93	static int crypt(const struct cipher_desc *desc,
1da177e4 LT	94	struct scatterlist *dst,
1da177e4 LT	95	struct scatterlist *src,
c774e93e	96	unsigned int nbytes)
1da177e4 LT	97	{
1da177e4 LT	98	struct scatter_walk walk_in, walk_out;
c774e93e	99	struct crypto_tfm *tfm = desc->tfm;
1da177e4	100	const unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
fbdae9f3	101	unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
95477377	102	unsigned long buffer = 0;
1da177e4 LT	103
	104	if (!nbytes)
	105	return 0;
	106
	107	if (nbytes % bsize) {
	108	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
	109	return -EINVAL;
	110	}
	111
	112	scatterwalk_start(&walk_in, src);
	113	scatterwalk_start(&walk_out, dst);
	114
	115	for(;;) {
95477377 HX	116	unsigned int n = nbytes;
	117	u8 *tmp = NULL;
	118
	119	if (!scatterwalk_aligned(&walk_in, alignmask) \|\|
	120	!scatterwalk_aligned(&walk_out, alignmask)) {
	121	if (!buffer) {
	122	buffer = __get_free_page(GFP_ATOMIC);
	123	if (!buffer)
	124	n = 0;
	125	}
	126	tmp = (u8 *)buffer;
	127	}
1da177e4 LT	128
	129	scatterwalk_map(&walk_in, 0);
	130	scatterwalk_map(&walk_out, 1);
	131
95477377	132	n = scatterwalk_clamp(&walk_in, n);
c774e93e	133	n = scatterwalk_clamp(&walk_out, n);
1da177e4	134
c774e93e	135	if (likely(n >= bsize))
95477377	136	n = crypt_fast(desc, &walk_in, &walk_out, n, tmp);
c774e93e HX	137	else
c774e93e HX	138	n = crypt_slow(desc, &walk_in, &walk_out, bsize);
1da177e4	139
c774e93e	140	nbytes -= n;
1da177e4 LT	141
	142	scatterwalk_done(&walk_in, 0, nbytes);
	143	scatterwalk_done(&walk_out, 1, nbytes);
	144
	145	if (!nbytes)
95477377	146	break;
1da177e4 LT	147
	148	crypto_yield(tfm);
	149	}
95477377 HX	150
	151	if (buffer)
	152	free_page(buffer);
	153
	154	return 0;
1da177e4 LT	155	}
1da177e4 LT	156
915e8561 HX	157	static int crypt_iv_unaligned(struct cipher_desc *desc,
	158	struct scatterlist *dst,
	159	struct scatterlist *src,
	160	unsigned int nbytes)
	161	{
	162	struct crypto_tfm *tfm = desc->tfm;
	163	unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
	164	u8 *iv = desc->info;
	165
	166	if (unlikely(((unsigned long)iv & alignmask))) {
	167	unsigned int ivsize = tfm->crt_cipher.cit_ivsize;
	168	u8 buffer[ivsize + alignmask];
	169	u8 tmp = (u8 )ALIGN((unsigned long)buffer, alignmask + 1);
	170	int err;
	171
	172	desc->info = memcpy(tmp, iv, ivsize);
	173	err = crypt(desc, dst, src, nbytes);
	174	memcpy(iv, tmp, ivsize);
	175
	176	return err;
	177	}
	178
	179	return crypt(desc, dst, src, nbytes);
	180	}
	181
c774e93e HX	182	static unsigned int cbc_process_encrypt(const struct cipher_desc *desc,
	183	u8 dst, const u8 src,
	184	unsigned int nbytes)
1da177e4	185	{
c774e93e HX	186	struct crypto_tfm *tfm = desc->tfm;
	187	void (xor)(u8 , const u8 *) = tfm->crt_u.cipher.cit_xor_block;
	188	int bsize = crypto_tfm_alg_blocksize(tfm);
	189
	190	void (fn)(void , u8 , const u8 ) = desc->crfn;
	191	u8 *iv = desc->info;
	192	unsigned int done = 0;
	193
	194	do {
	195	xor(iv, src);
	196	fn(crypto_tfm_ctx(tfm), dst, iv);
	197	memcpy(iv, dst, bsize);
1da177e4	198
c774e93e HX	199	src += bsize;
	200	dst += bsize;
	201	} while ((done += bsize) < nbytes);
	202
	203	return done;
1da177e4 LT	204	}
1da177e4 LT	205
c774e93e HX	206	static unsigned int cbc_process_decrypt(const struct cipher_desc *desc,
	207	u8 dst, const u8 src,
	208	unsigned int nbytes)
1da177e4	209	{
c774e93e HX	210	struct crypto_tfm *tfm = desc->tfm;
	211	void (xor)(u8 , const u8 *) = tfm->crt_u.cipher.cit_xor_block;
	212	int bsize = crypto_tfm_alg_blocksize(tfm);
	213
	214	u8 stack[src == dst ? bsize : 0];
	215	u8 *buf = stack;
	216	u8 **dst_p = src == dst ? &buf : &dst;
	217
	218	void (fn)(void , u8 , const u8 ) = desc->crfn;
	219	u8 *iv = desc->info;
	220	unsigned int done = 0;
	221
	222	do {
	223	u8 tmp_dst = dst_p;
1da177e4	224
c774e93e HX	225	fn(crypto_tfm_ctx(tfm), tmp_dst, src);
	226	xor(tmp_dst, iv);
	227	memcpy(iv, src, bsize);
	228	if (tmp_dst != dst)
	229	memcpy(dst, tmp_dst, bsize);
	230
	231	src += bsize;
	232	dst += bsize;
	233	} while ((done += bsize) < nbytes);
	234
	235	return done;
1da177e4 LT	236	}
1da177e4 LT	237
c774e93e HX	238	static unsigned int ecb_process(const struct cipher_desc desc, u8 dst,
c774e93e HX	239	const u8 *src, unsigned int nbytes)
1da177e4	240	{
c774e93e HX	241	struct crypto_tfm *tfm = desc->tfm;
	242	int bsize = crypto_tfm_alg_blocksize(tfm);
	243	void (fn)(void , u8 , const u8 ) = desc->crfn;
	244	unsigned int done = 0;
	245
	246	do {
	247	fn(crypto_tfm_ctx(tfm), dst, src);
	248
	249	src += bsize;
	250	dst += bsize;
	251	} while ((done += bsize) < nbytes);
	252
	253	return done;
1da177e4 LT	254	}
	255
	256	static int setkey(struct crypto_tfm tfm, const u8 key, unsigned int keylen)
	257	{
	258	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
	259
	260	if (keylen < cia->cia_min_keysize \|\| keylen > cia->cia_max_keysize) {
	261	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	262	return -EINVAL;
	263	} else
	264	return cia->cia_setkey(crypto_tfm_ctx(tfm), key, keylen,
	265	&tfm->crt_flags);
	266	}
	267
	268	static int ecb_encrypt(struct crypto_tfm *tfm,
	269	struct scatterlist *dst,
	270	struct scatterlist *src, unsigned int nbytes)
	271	{
c774e93e	272	struct cipher_desc desc;
40725181	273	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
c774e93e HX	274
c774e93e HX	275	desc.tfm = tfm;
40725181 HX	276	desc.crfn = cipher->cia_encrypt;
40725181 HX	277	desc.prfn = cipher->cia_encrypt_ecb ?: ecb_process;
c774e93e HX	278
c774e93e HX	279	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	280	}
	281
	282	static int ecb_decrypt(struct crypto_tfm *tfm,
	283	struct scatterlist *dst,
	284	struct scatterlist *src,
	285	unsigned int nbytes)
	286	{
c774e93e	287	struct cipher_desc desc;
40725181	288	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
c774e93e HX	289
c774e93e HX	290	desc.tfm = tfm;
40725181 HX	291	desc.crfn = cipher->cia_decrypt;
40725181 HX	292	desc.prfn = cipher->cia_decrypt_ecb ?: ecb_process;
c774e93e HX	293
c774e93e HX	294	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	295	}
	296
	297	static int cbc_encrypt(struct crypto_tfm *tfm,
	298	struct scatterlist *dst,
	299	struct scatterlist *src,
	300	unsigned int nbytes)
	301	{
c774e93e	302	struct cipher_desc desc;
40725181	303	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
c774e93e HX	304
c774e93e HX	305	desc.tfm = tfm;
40725181 HX	306	desc.crfn = cipher->cia_encrypt;
40725181 HX	307	desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
c774e93e HX	308	desc.info = tfm->crt_cipher.cit_iv;
	309
	310	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	311	}
	312
	313	static int cbc_encrypt_iv(struct crypto_tfm *tfm,
	314	struct scatterlist *dst,
	315	struct scatterlist *src,
	316	unsigned int nbytes, u8 *iv)
	317	{
c774e93e	318	struct cipher_desc desc;
40725181	319	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
c774e93e HX	320
c774e93e HX	321	desc.tfm = tfm;
40725181 HX	322	desc.crfn = cipher->cia_encrypt;
40725181 HX	323	desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
c774e93e HX	324	desc.info = iv;
c774e93e HX	325
915e8561	326	return crypt_iv_unaligned(&desc, dst, src, nbytes);
1da177e4 LT	327	}
	328
	329	static int cbc_decrypt(struct crypto_tfm *tfm,
	330	struct scatterlist *dst,
	331	struct scatterlist *src,
	332	unsigned int nbytes)
	333	{
c774e93e	334	struct cipher_desc desc;
40725181	335	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
c774e93e HX	336
c774e93e HX	337	desc.tfm = tfm;
40725181 HX	338	desc.crfn = cipher->cia_decrypt;
40725181 HX	339	desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
c774e93e HX	340	desc.info = tfm->crt_cipher.cit_iv;
	341
	342	return crypt(&desc, dst, src, nbytes);
1da177e4 LT	343	}
	344
	345	static int cbc_decrypt_iv(struct crypto_tfm *tfm,
	346	struct scatterlist *dst,
	347	struct scatterlist *src,
	348	unsigned int nbytes, u8 *iv)
	349	{
c774e93e	350	struct cipher_desc desc;
40725181	351	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
c774e93e HX	352
c774e93e HX	353	desc.tfm = tfm;
40725181 HX	354	desc.crfn = cipher->cia_decrypt;
40725181 HX	355	desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
c774e93e HX	356	desc.info = iv;
c774e93e HX	357
915e8561	358	return crypt_iv_unaligned(&desc, dst, src, nbytes);
1da177e4 LT	359	}
	360
	361	static int nocrypt(struct crypto_tfm *tfm,
	362	struct scatterlist *dst,
	363	struct scatterlist *src,
	364	unsigned int nbytes)
	365	{
	366	return -ENOSYS;
	367	}
	368
	369	static int nocrypt_iv(struct crypto_tfm *tfm,
	370	struct scatterlist *dst,
	371	struct scatterlist *src,
	372	unsigned int nbytes, u8 *iv)
	373	{
	374	return -ENOSYS;
	375	}
	376
	377	int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags)
	378	{
	379	u32 mode = flags & CRYPTO_TFM_MODE_MASK;
	380
	381	tfm->crt_cipher.cit_mode = mode ? mode : CRYPTO_TFM_MODE_ECB;
	382	if (flags & CRYPTO_TFM_REQ_WEAK_KEY)
	383	tfm->crt_flags = CRYPTO_TFM_REQ_WEAK_KEY;
	384
	385	return 0;
	386	}
	387
	388	int crypto_init_cipher_ops(struct crypto_tfm *tfm)
	389	{
	390	int ret = 0;
	391	struct cipher_tfm *ops = &tfm->crt_cipher;
	392
	393	ops->cit_setkey = setkey;
	394
	395	switch (tfm->crt_cipher.cit_mode) {
	396	case CRYPTO_TFM_MODE_ECB:
	397	ops->cit_encrypt = ecb_encrypt;
	398	ops->cit_decrypt = ecb_decrypt;
	399	break;
	400
	401	case CRYPTO_TFM_MODE_CBC:
	402	ops->cit_encrypt = cbc_encrypt;
	403	ops->cit_decrypt = cbc_decrypt;
	404	ops->cit_encrypt_iv = cbc_encrypt_iv;
	405	ops->cit_decrypt_iv = cbc_decrypt_iv;
	406	break;
	407
	408	case CRYPTO_TFM_MODE_CFB:
	409	ops->cit_encrypt = nocrypt;
	410	ops->cit_decrypt = nocrypt;
	411	ops->cit_encrypt_iv = nocrypt_iv;
	412	ops->cit_decrypt_iv = nocrypt_iv;
	413	break;
	414
	415	case CRYPTO_TFM_MODE_CTR:
	416	ops->cit_encrypt = nocrypt;
	417	ops->cit_decrypt = nocrypt;
	418	ops->cit_encrypt_iv = nocrypt_iv;
	419	ops->cit_decrypt_iv = nocrypt_iv;
	420	break;
	421
	422	default:
423	BUG();
424	}
425
426	if (ops->cit_mode == CRYPTO_TFM_MODE_CBC) {
fbdae9f3 HX	427	unsigned int align;
fbdae9f3 HX	428	unsigned long addr;
1da177e4 LT	429
	430	switch (crypto_tfm_alg_blocksize(tfm)) {
	431	case 8:
	432	ops->cit_xor_block = xor_64;
	433	break;
	434
	435	case 16:
	436	ops->cit_xor_block = xor_128;
	437	break;
	438
	439	default:
	440	printk(KERN_WARNING "%s: block size %u not supported\n",
	441	crypto_tfm_alg_name(tfm),
	442	crypto_tfm_alg_blocksize(tfm));
	443	ret = -EINVAL;
	444	goto out;
	445	}
	446
	447	ops->cit_ivsize = crypto_tfm_alg_blocksize(tfm);
fbdae9f3 HX	448	align = crypto_tfm_alg_alignmask(tfm) + 1;
	449	addr = (unsigned long)crypto_tfm_ctx(tfm);
	450	addr = ALIGN(addr, align);
	451	addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
	452	ops->cit_iv = (void *)addr;
1da177e4 LT	453	}
	454
	455	out:
	456	return ret;
	457	}
	458
	459	void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
	460	{
1da177e4	461	}