/* * Copyright (C)2006 USAGI/WIDE Project * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA * * Author: * 	Kazunori Miyazawa <miyazawa@linux-ipv6.org> */ #include <linux/crypto.h>#include <linux/err.h>#include <linux/hardirq.h>#include <linux/kernel.h>#include <linux/mm.h>#include <linux/rtnetlink.h>#include <linux/slab.h>#include <linux/scatterlist.h>#include "internal.h" static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101,			   0x02020202, 0x02020202, 0x02020202, 0x02020202,			   0x03030303, 0x03030303, 0x03030303, 0x03030303};/* * +------------------------ * | <parent tfm> * +------------------------ * | crypto_xcbc_ctx * +------------------------ * | odds (block size) * +------------------------ * | prev (block size) * +------------------------ * | key (block size) * +------------------------ * | consts (block size * 3) * +------------------------ */struct crypto_xcbc_ctx {	struct crypto_cipher *child;	u8 *odds;	u8 *prev;	u8 *key;	u8 *consts;	void (*xor)(u8 *a, const u8 *b, unsigned int bs);	unsigned int keylen;	unsigned int len;}; static void xor_128(u8 *a, const u8 *b, unsigned int bs){	((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 int _crypto_xcbc_digest_setkey(struct crypto_hash *parent,				      struct crypto_xcbc_ctx *ctx){	int bs = crypto_hash_blocksize(parent);	int err = 0;	u8 key1[bs]; 	if ((err = crypto_cipher_setkey(ctx->child, ctx->key, ctx->keylen)))	    return err; 	crypto_cipher_encrypt_one(ctx->child, key1, ctx->consts); 	return crypto_cipher_setkey(ctx->child, key1, bs);} static int crypto_xcbc_digest_setkey(struct crypto_hash *parent,				     const u8 *inkey, unsigned int keylen){	struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent); 	if (keylen != crypto_cipher_blocksize(ctx->child))		return -EINVAL; 	ctx->keylen = keylen;	memcpy(ctx->key, inkey, keylen);	ctx->consts = (u8*)ks; 	return _crypto_xcbc_digest_setkey(parent, ctx);} static int crypto_xcbc_digest_init(struct hash_desc *pdesc){	struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(pdesc->tfm);	int bs = crypto_hash_blocksize(pdesc->tfm); 	ctx->len = 0;	memset(ctx->odds, 0, bs);	memset(ctx->prev, 0, bs); 	return 0;} static int crypto_xcbc_digest_update2(struct hash_desc *pdesc,				      struct scatterlist *sg,				      unsigned int nbytes){	struct crypto_hash *parent = pdesc->tfm;	struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);	struct crypto_cipher *tfm = ctx->child;	int bs = crypto_hash_blocksize(parent);	unsigned int i = 0; 	do { 		struct page *pg = sg[i].page;		unsigned int offset = sg[i].offset;		unsigned int slen = sg[i].length; 		while (slen > 0) {			unsigned int len = min(slen, ((unsigned int)(PAGE_SIZE)) - offset);			char *p = crypto_kmap(pg, 0) + offset; 			/* checking the data can fill the block */			if ((ctx->len + len) <= bs) {				memcpy(ctx->odds + ctx->len, p, len);				ctx->len += len;				slen -= len; 				/* checking the rest of the page */				if (len + offset >= PAGE_SIZE) {					offset = 0;					pg++;				} else					offset += len; 				crypto_kunmap(p, 0);				crypto_yield(pdesc->flags);				continue;			} 			/* filling odds with new data and encrypting it */			memcpy(ctx->odds + ctx->len, p, bs - ctx->len);			len -= bs - ctx->len;			p += bs - ctx->len; 			ctx->xor(ctx->prev, ctx->odds, bs);			crypto_cipher_encrypt_one(tfm, ctx->prev, ctx->prev); 			/* clearing the length */			ctx->len = 0; 			/* encrypting the rest of data */			while (len > bs) {				ctx->xor(ctx->prev, p, bs);				crypto_cipher_encrypt_one(tfm, ctx->prev,							  ctx->prev);				p += bs;				len -= bs;			} 			/* keeping the surplus of blocksize */			if (len) {				memcpy(ctx->odds, p, len);				ctx->len = len;			}			crypto_kunmap(p, 0);			crypto_yield(pdesc->flags);			slen -= min(slen, ((unsigned int)(PAGE_SIZE)) - offset);			offset = 0;			pg++;		}		nbytes-=sg[i].length;		i++;	} while (nbytes>0); 	return 0;} static int crypto_xcbc_digest_update(struct hash_desc *pdesc,				     struct scatterlist *sg,				     unsigned int nbytes){	if (WARN_ON_ONCE(in_irq()))		return -EDEADLK;	return crypto_xcbc_digest_update2(pdesc, sg, nbytes);} static int crypto_xcbc_digest_final(struct hash_desc *pdesc, u8 *out){	struct crypto_hash *parent = pdesc->tfm;	struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);	struct crypto_cipher *tfm = ctx->child;	int bs = crypto_hash_blocksize(parent);	int err = 0; 	if (ctx->len == bs) {		u8 key2[bs]; 		if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0)			return err; 		crypto_cipher_encrypt_one(tfm, key2,					  (u8 *)(ctx->consts + bs)); 		ctx->xor(ctx->prev, ctx->odds, bs);		ctx->xor(ctx->prev, key2, bs);		_crypto_xcbc_digest_setkey(parent, ctx); 		crypto_cipher_encrypt_one(tfm, out, ctx->prev);	} else {		u8 key3[bs];		unsigned int rlen;		u8 *p = ctx->odds + ctx->len;		*p = 0x80;		p++; 		rlen = bs - ctx->len -1;		if (rlen)			memset(p, 0, rlen); 		if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0)			return err; 		crypto_cipher_encrypt_one(tfm, key3,					  (u8 *)(ctx->consts + bs * 2)); 		ctx->xor(ctx->prev, ctx->odds, bs);		ctx->xor(ctx->prev, key3, bs); 		_crypto_xcbc_digest_setkey(parent, ctx); 		crypto_cipher_encrypt_one(tfm, out, ctx->prev);	} 	return 0;} static int crypto_xcbc_digest(struct hash_desc *pdesc,		  struct scatterlist *sg, unsigned int nbytes, u8 *out){	if (WARN_ON_ONCE(in_irq()))		return -EDEADLK; 	crypto_xcbc_digest_init(pdesc);	crypto_xcbc_digest_update2(pdesc, sg, nbytes);	return crypto_xcbc_digest_final(pdesc, out);} static int xcbc_init_tfm(struct crypto_tfm *tfm){	struct crypto_cipher *cipher;	struct crypto_instance *inst = (void *)tfm->__crt_alg;	struct crypto_spawn *spawn = crypto_instance_ctx(inst);	struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm));	int bs = crypto_hash_blocksize(__crypto_hash_cast(tfm)); 	cipher = crypto_spawn_cipher(spawn);	if (IS_ERR(cipher))		return PTR_ERR(cipher); 	switch(bs) {	case 16:		ctx->xor = xor_128;		break;	default:		return -EINVAL;	} 	ctx->child = cipher;	ctx->odds = (u8*)(ctx+1);	ctx->prev = ctx->odds + bs;	ctx->key = ctx->prev + bs; 	return 0;}; static void xcbc_exit_tfm(struct crypto_tfm *tfm){	struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm));	crypto_free_cipher(ctx->child);} static struct crypto_instance *xcbc_alloc(void *param, unsigned int len){	struct crypto_instance *inst;	struct crypto_alg *alg;	alg = crypto_get_attr_alg(param, len, CRYPTO_ALG_TYPE_CIPHER,				  CRYPTO_ALG_TYPE_HASH_MASK | CRYPTO_ALG_ASYNC);	if (IS_ERR(alg))		return ERR_PTR(PTR_ERR(alg)); 	switch(alg->cra_blocksize) {	case 16:		break;	default:		return ERR_PTR(PTR_ERR(alg));	} 	inst = crypto_alloc_instance("xcbc", alg);	if (IS_ERR(inst))		goto out_put_alg; 	inst->alg.cra_flags = CRYPTO_ALG_TYPE_HASH;	inst->alg.cra_priority = alg->cra_priority;	inst->alg.cra_blocksize = alg->cra_blocksize;	inst->alg.cra_alignmask = alg->cra_alignmask;	inst->alg.cra_type = &crypto_hash_type; 	inst->alg.cra_hash.digestsize =		(alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==		CRYPTO_ALG_TYPE_HASH ? alg->cra_hash.digestsize :				       alg->cra_blocksize;	inst->alg.cra_ctxsize = sizeof(struct crypto_xcbc_ctx) +				ALIGN(inst->alg.cra_blocksize * 3, sizeof(void *));	inst->alg.cra_init = xcbc_init_tfm;	inst->alg.cra_exit = xcbc_exit_tfm; 	inst->alg.cra_hash.init = crypto_xcbc_digest_init;	inst->alg.cra_hash.update = crypto_xcbc_digest_update;	inst->alg.cra_hash.final = crypto_xcbc_digest_final;	inst->alg.cra_hash.digest = crypto_xcbc_digest;	inst->alg.cra_hash.setkey = crypto_xcbc_digest_setkey; out_put_alg:	crypto_mod_put(alg);	return inst;} static void xcbc_free(struct crypto_instance *inst){	crypto_drop_spawn(crypto_instance_ctx(inst));	kfree(inst);} static struct crypto_template crypto_xcbc_tmpl = {	.name = "xcbc",	.alloc = xcbc_alloc,	.free = xcbc_free,	.module = THIS_MODULE,}; static int __init crypto_xcbc_module_init(void){	return crypto_register_template(&crypto_xcbc_tmpl);} static void __exit crypto_xcbc_module_exit(void){	crypto_unregister_template(&crypto_xcbc_tmpl);} module_init(crypto_xcbc_module_init);module_exit(crypto_xcbc_module_exit); MODULE_LICENSE("GPL");MODULE_DESCRIPTION("XCBC keyed hash algorithm");