[CRYPTO] xcbc: New algorithm (333b0d7e) · Commits · e / devices / android_kernel_xiaomi_nabu

crypto/Kconfig

+11 −0

Original line number	Diff line number	Diff line
		@@ -39,6 +39,17 @@ config CRYPTO_HMAC
		HMAC: Keyed-Hashing for Message Authentication (RFC2104).
		This is required for IPSec.

		config CRYPTO_XCBC
		tristate "XCBC support"
		depends on EXPERIMENTAL
		select CRYPTO_HASH
		select CRYPTO_MANAGER
		help
		XCBC: Keyed-Hashing with encryption algorithm
		http://www.ietf.org/rfc/rfc3566.txt
		http://csrc.nist.gov/encryption/modes/proposedmodes/
		xcbc-mac/xcbc-mac-spec.pdf

		config CRYPTO_NULL
		tristate "Null algorithms"
		select CRYPTO_ALGAPI

crypto/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -15,6 +15,7 @@ obj-$(CONFIG_CRYPTO_HASH) += crypto_hash.o

		obj-$(CONFIG_CRYPTO_MANAGER) += cryptomgr.o
		obj-$(CONFIG_CRYPTO_HMAC) += hmac.o
		obj-$(CONFIG_CRYPTO_XCBC) += xcbc.o
		obj-$(CONFIG_CRYPTO_NULL) += crypto_null.o
		obj-$(CONFIG_CRYPTO_MD4) += md4.o
		obj-$(CONFIG_CRYPTO_MD5) += md5.o

crypto/xcbc.c

0 → 100644

+346 −0

Original line number	Diff line number	Diff line
		/*
		* 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/kernel.h>
		#include <linux/mm.h>
		#include <linux/rtnetlink.h>
		#include <linux/slab.h>
		#include <linux/scatterlist.h>
		#include "internal.h"

		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_tfm *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;

		ctx->child->__crt_alg->cra_cipher.cia_encrypt(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_tfm_alg_blocksize(ctx->child))
		return -EINVAL;

		ctx->keylen = keylen;
		memcpy(ctx->key, inkey, keylen);
		ctx->consts = (u8*)ks;

		return _crypto_xcbc_digest_setkey(parent, ctx);
		}

		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;
		}

		int crypto_xcbc_digest_update(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_tfm *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(tfm->crt_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);
		tfm->__crt_alg->cra_cipher.cia_encrypt(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);
		tfm->__crt_alg->cra_cipher.cia_encrypt(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(tfm->crt_flags);
		slen -= min(slen, ((unsigned int)(PAGE_SIZE)) - offset);
		offset = 0;
		pg++;
		}
		nbytes-=sg[i].length;
		i++;
		} while (nbytes>0);

		return 0;
		}

		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_tfm *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;

		tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, key2, (const u8*)(ctx->consts+bs));

		ctx->xor(ctx->prev, ctx->odds, bs);
		ctx->xor(ctx->prev, key2, bs);
		_crypto_xcbc_digest_setkey(parent, ctx);

		tfm->__crt_alg->cra_cipher.cia_encrypt(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;

		tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, key3, (const u8)(ctx->consts+bs2));

		ctx->xor(ctx->prev, ctx->odds, bs);
		ctx->xor(ctx->prev, key3, bs);

		_crypto_xcbc_digest_setkey(parent, ctx);

		tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, out, ctx->prev);
		}

		return 0;
		}

		static int crypto_xcbc_digest(struct hash_desc *pdesc,
		struct scatterlist sg, unsigned int nbytes, u8 out)
		{
		crypto_xcbc_digest_init(pdesc);
		crypto_xcbc_digest_update(pdesc, sg, nbytes);
		return crypto_xcbc_digest_final(pdesc, out);
		}

		static int xcbc_init_tfm(struct crypto_tfm *tfm)
		{
		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));

		tfm = crypto_spawn_tfm(spawn);
		if (IS_ERR(tfm))
		return PTR_ERR(tfm);

		switch(bs) {
		case 16:
		ctx->xor = xor_128;
		break;
		default:
		return -EINVAL;
		}

		ctx->child = crypto_cipher_cast(tfm);
		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");