[linux-2.6-block.git] / crypto / ahash.c

/*
 * Asynchronous Cryptographic Hash operations.
 *
 * This is the asynchronous version of hash.c with notification of
 * completion via a callback.
 *
 * Copyright (c) 2008 Loc Ho <lho@amcc.com>
 *
 * 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 <crypto/internal/hash.h>
#include <crypto/scatterwalk.h>
#include <linux/bug.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/cryptouser.h>
#include <net/netlink.h>

#include "internal.h"

struct ahash_request_priv {
	crypto_completion_t complete;
	void *data;
	u8 *result;
	void *ubuf[] CRYPTO_MINALIGN_ATTR;
};

static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash)
{
	return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
			    halg);
}

static int hash_walk_next(struct crypto_hash_walk *walk)
{
	unsigned int alignmask = walk->alignmask;
	unsigned int offset = walk->offset;
	unsigned int nbytes = min(walk->entrylen,
				  ((unsigned int)(PAGE_SIZE)) - offset);

	if (walk->flags & CRYPTO_ALG_ASYNC)
		walk->data = kmap(walk->pg);
	else
		walk->data = kmap_atomic(walk->pg);
	walk->data += offset;

	if (offset & alignmask) {
		unsigned int unaligned = alignmask + 1 - (offset & alignmask);

		if (nbytes > unaligned)
			nbytes = unaligned;
	}

	walk->entrylen -= nbytes;
	return nbytes;
}

static int hash_walk_new_entry(struct crypto_hash_walk *walk)
{
	struct scatterlist *sg;

	sg = walk->sg;
	walk->offset = sg->offset;
	walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
	walk->offset = offset_in_page(walk->offset);
	walk->entrylen = sg->length;

	if (walk->entrylen > walk->total)
		walk->entrylen = walk->total;
	walk->total -= walk->entrylen;

	return hash_walk_next(walk);
}

int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
{
	unsigned int alignmask = walk->alignmask;
	unsigned int nbytes = walk->entrylen;

	walk->data -= walk->offset;

	if (nbytes && walk->offset & alignmask && !err) {
		walk->offset = ALIGN(walk->offset, alignmask + 1);
		walk->data += walk->offset;

		nbytes = min(nbytes,
			     ((unsigned int)(PAGE_SIZE)) - walk->offset);
		walk->entrylen -= nbytes;

		return nbytes;
	}

	if (walk->flags & CRYPTO_ALG_ASYNC)
		kunmap(walk->pg);
	else {
		kunmap_atomic(walk->data);
		/*
		 * The may sleep test only makes sense for sync users.
		 * Async users don't need to sleep here anyway.
		 */
		crypto_yield(walk->flags);
	}

	if (err)
		return err;

	if (nbytes) {
		walk->offset = 0;
		walk->pg++;
		return hash_walk_next(walk);
	}

	if (!walk->total)
		return 0;

	walk->sg = sg_next(walk->sg);

	return hash_walk_new_entry(walk);
}
EXPORT_SYMBOL_GPL(crypto_hash_walk_done);

int crypto_hash_walk_first(struct ahash_request *req,
			   struct crypto_hash_walk *walk)
{
	walk->total = req->nbytes;

	if (!walk->total) {
		walk->entrylen = 0;
		return 0;
	}

	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	walk->sg = req->src;
	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;

	return hash_walk_new_entry(walk);
}
EXPORT_SYMBOL_GPL(crypto_hash_walk_first);

int crypto_ahash_walk_first(struct ahash_request *req,
			    struct crypto_hash_walk *walk)
{
	walk->total = req->nbytes;

	if (!walk->total) {
		walk->entrylen = 0;
		return 0;
	}

	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	walk->sg = req->src;
	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
	walk->flags |= CRYPTO_ALG_ASYNC;

	BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);

	return hash_walk_new_entry(walk);
}
EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);

static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
				unsigned int keylen)
{
	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	int ret;
	u8 *buffer, *alignbuffer;
	unsigned long absize;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_KERNEL);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = tfm->setkey(tfm, alignbuffer, keylen);
	kzfree(buffer);
	return ret;
}

int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
			unsigned int keylen)
{
	unsigned long alignmask = crypto_ahash_alignmask(tfm);

	if ((unsigned long)key & alignmask)
		return ahash_setkey_unaligned(tfm, key, keylen);

	return tfm->setkey(tfm, key, keylen);
}
EXPORT_SYMBOL_GPL(crypto_ahash_setkey);

static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
			  unsigned int keylen)
{
	return -ENOSYS;
}

static inline unsigned int ahash_align_buffer_size(unsigned len,
						   unsigned long mask)
{
	return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
}

static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	unsigned int ds = crypto_ahash_digestsize(tfm);
	struct ahash_request_priv *priv;

	priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
		       (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
		       GFP_KERNEL : GFP_ATOMIC);
	if (!priv)
		return -ENOMEM;

	/*
	 * WARNING: Voodoo programming below!
	 *
	 * The code below is obscure and hard to understand, thus explanation
	 * is necessary. See include/crypto/hash.h and include/linux/crypto.h
	 * to understand the layout of structures used here!
	 *
	 * The code here will replace portions of the ORIGINAL request with
	 * pointers to new code and buffers so the hashing operation can store
	 * the result in aligned buffer. We will call the modified request
	 * an ADJUSTED request.
	 *
	 * The newly mangled request will look as such:
	 *
	 * req {
	 *   .result        = ADJUSTED[new aligned buffer]
	 *   .base.complete = ADJUSTED[pointer to completion function]
	 *   .base.data     = ADJUSTED[*req (pointer to self)]
	 *   .priv          = ADJUSTED[new priv] {
	 *           .result   = ORIGINAL(result)
	 *           .complete = ORIGINAL(base.complete)
	 *           .data     = ORIGINAL(base.data)
	 *   }
	 */

	priv->result = req->result;
	priv->complete = req->base.complete;
	priv->data = req->base.data;
	/*
	 * WARNING: We do not backup req->priv here! The req->priv
	 *          is for internal use of the Crypto API and the
	 *          user must _NOT_ _EVER_ depend on it's content!
	 */

	req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
	req->base.complete = cplt;
	req->base.data = req;
	req->priv = priv;

	return 0;
}

static void ahash_restore_req(struct ahash_request *req)
{
	struct ahash_request_priv *priv = req->priv;

	/* Restore the original crypto request. */
	req->result = priv->result;
	req->base.complete = priv->complete;
	req->base.data = priv->data;
	req->priv = NULL;

	/* Free the req->priv.priv from the ADJUSTED request. */
	kzfree(priv);
}

static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
{
	struct ahash_request_priv *priv = req->priv;

	if (err == -EINPROGRESS)
		return;

	if (!err)
		memcpy(priv->result, req->result,
		       crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));

	ahash_restore_req(req);
}

static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
{
	struct ahash_request *areq = req->data;

	/*
	 * Restore the original request, see ahash_op_unaligned() for what
	 * goes where.
	 *
	 * The "struct ahash_request *req" here is in fact the "req.base"
	 * from the ADJUSTED request from ahash_op_unaligned(), thus as it
	 * is a pointer to self, it is also the ADJUSTED "req" .
	 */

	/* First copy req->result into req->priv.result */
	ahash_op_unaligned_finish(areq, err);

	/* Complete the ORIGINAL request. */
	areq->base.complete(&areq->base, err);
}

static int ahash_op_unaligned(struct ahash_request *req,
			      int (*op)(struct ahash_request *))
{
	int err;

	err = ahash_save_req(req, ahash_op_unaligned_done);
	if (err)
		return err;

	err = op(req);
	ahash_op_unaligned_finish(req, err);

	return err;
}

static int crypto_ahash_op(struct ahash_request *req,
			   int (*op)(struct ahash_request *))
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	unsigned long alignmask = crypto_ahash_alignmask(tfm);

	if ((unsigned long)req->result & alignmask)
		return ahash_op_unaligned(req, op);

	return op(req);
}

int crypto_ahash_final(struct ahash_request *req)
{
	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
}
EXPORT_SYMBOL_GPL(crypto_ahash_final);

int crypto_ahash_finup(struct ahash_request *req)
{
	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
}
EXPORT_SYMBOL_GPL(crypto_ahash_finup);

int crypto_ahash_digest(struct ahash_request *req)
{
	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
}
EXPORT_SYMBOL_GPL(crypto_ahash_digest);

static void ahash_def_finup_finish2(struct ahash_request *req, int err)
{
	struct ahash_request_priv *priv = req->priv;

	if (err == -EINPROGRESS)
		return;

	if (!err)
		memcpy(priv->result, req->result,
		       crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));

	ahash_restore_req(req);
}

static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
{
	struct ahash_request *areq = req->data;

	ahash_def_finup_finish2(areq, err);

	areq->base.complete(&areq->base, err);
}

static int ahash_def_finup_finish1(struct ahash_request *req, int err)
{
	if (err)
		goto out;

	req->base.complete = ahash_def_finup_done2;
	req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	err = crypto_ahash_reqtfm(req)->final(req);

out:
	ahash_def_finup_finish2(req, err);
	return err;
}

static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
{
	struct ahash_request *areq = req->data;

	err = ahash_def_finup_finish1(areq, err);

	areq->base.complete(&areq->base, err);
}

static int ahash_def_finup(struct ahash_request *req)
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	int err;

	err = ahash_save_req(req, ahash_def_finup_done1);
	if (err)
		return err;

	err = tfm->update(req);
	return ahash_def_finup_finish1(req, err);
}

static int ahash_no_export(struct ahash_request *req, void *out)
{
	return -ENOSYS;
}

static int ahash_no_import(struct ahash_request *req, const void *in)
{
	return -ENOSYS;
}

static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
{
	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
	struct ahash_alg *alg = crypto_ahash_alg(hash);

	hash->setkey = ahash_nosetkey;
	hash->has_setkey = false;
	hash->export = ahash_no_export;
	hash->import = ahash_no_import;

	if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
		return crypto_init_shash_ops_async(tfm);

	hash->init = alg->init;
	hash->update = alg->update;
	hash->final = alg->final;
	hash->finup = alg->finup ?: ahash_def_finup;
	hash->digest = alg->digest;

	if (alg->setkey) {
		hash->setkey = alg->setkey;
		hash->has_setkey = true;
	}
	if (alg->export)
		hash->export = alg->export;
	if (alg->import)
		hash->import = alg->import;

	return 0;
}

static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
{
	if (alg->cra_type == &crypto_ahash_type)
		return alg->cra_ctxsize;

	return sizeof(struct crypto_shash *);
}

#ifdef CONFIG_NET
static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_hash rhash;

	strncpy(rhash.type, "ahash", sizeof(rhash.type));

	rhash.blocksize = alg->cra_blocksize;
	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;

	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
		    sizeof(struct crypto_report_hash), &rhash))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}
#else
static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	return -ENOSYS;
}
#endif

static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));
static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
{
	seq_printf(m, "type         : ahash\n");
	seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
					     "yes" : "no");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "digestsize   : %u\n",
		   __crypto_hash_alg_common(alg)->digestsize);
}

const struct crypto_type crypto_ahash_type = {
	.extsize = crypto_ahash_extsize,
	.init_tfm = crypto_ahash_init_tfm,
#ifdef CONFIG_PROC_FS
	.show = crypto_ahash_show,
#endif
	.report = crypto_ahash_report,
	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	.type = CRYPTO_ALG_TYPE_AHASH,
	.tfmsize = offsetof(struct crypto_ahash, base),
};
EXPORT_SYMBOL_GPL(crypto_ahash_type);

struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
					u32 mask)
{
	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_alloc_ahash);

int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
{
	return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_has_ahash);

static int ahash_prepare_alg(struct ahash_alg *alg)
{
	struct crypto_alg *base = &alg->halg.base;

	if (alg->halg.digestsize > PAGE_SIZE / 8 ||
	    alg->halg.statesize > PAGE_SIZE / 8 ||
	    alg->halg.statesize == 0)
		return -EINVAL;

	base->cra_type = &crypto_ahash_type;
	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;

	return 0;
}

int crypto_register_ahash(struct ahash_alg *alg)
{
	struct crypto_alg *base = &alg->halg.base;
	int err;

	err = ahash_prepare_alg(alg);
	if (err)
		return err;

	return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_ahash);

int crypto_unregister_ahash(struct ahash_alg *alg)
{
	return crypto_unregister_alg(&alg->halg.base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_ahash);

int ahash_register_instance(struct crypto_template *tmpl,
			    struct ahash_instance *inst)
{
	int err;

	err = ahash_prepare_alg(&inst->alg);
	if (err)
		return err;

	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
}
EXPORT_SYMBOL_GPL(ahash_register_instance);

void ahash_free_instance(struct crypto_instance *inst)
{
	crypto_drop_spawn(crypto_instance_ctx(inst));
	kfree(ahash_instance(inst));
}
EXPORT_SYMBOL_GPL(ahash_free_instance);

int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
			    struct hash_alg_common *alg,
			    struct crypto_instance *inst)
{
	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
				  &crypto_ahash_type);
}
EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);

struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
{
	struct crypto_alg *alg;

	alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
	return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
}
EXPORT_SYMBOL_GPL(ahash_attr_alg);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Asynchronous cryptographic hash type");
Commit	Line	Data
004a403c LH	1	/*
	2	* Asynchronous Cryptographic Hash operations.
	3	*
	4	* This is the asynchronous version of hash.c with notification of
	5	* completion via a callback.
	6	*
	7	* Copyright (c) 2008 Loc Ho <lho@amcc.com>
	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
20036252 HX	16	#include <crypto/internal/hash.h>
20036252 HX	17	#include <crypto/scatterwalk.h>
75ecb231	18	#include <linux/bug.h>
004a403c LH	19	#include <linux/err.h>
	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
	22	#include <linux/sched.h>
	23	#include <linux/slab.h>
	24	#include <linux/seq_file.h>
6238cbae SK	25	#include <linux/cryptouser.h>
6238cbae SK	26	#include <net/netlink.h>
004a403c LH	27
	28	#include "internal.h"
	29
66f6ce5e HX	30	struct ahash_request_priv {
	31	crypto_completion_t complete;
	32	void *data;
	33	u8 *result;
	34	void *ubuf[] CRYPTO_MINALIGN_ATTR;
	35	};
	36
88056ec3 HX	37	static inline struct ahash_alg crypto_ahash_alg(struct crypto_ahash hash)
	38	{
	39	return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
	40	halg);
	41	}
	42
20036252 HX	43	static int hash_walk_next(struct crypto_hash_walk *walk)
	44	{
	45	unsigned int alignmask = walk->alignmask;
	46	unsigned int offset = walk->offset;
	47	unsigned int nbytes = min(walk->entrylen,
	48	((unsigned int)(PAGE_SIZE)) - offset);
	49
75ecb231 HX	50	if (walk->flags & CRYPTO_ALG_ASYNC)
	51	walk->data = kmap(walk->pg);
	52	else
	53	walk->data = kmap_atomic(walk->pg);
20036252 HX	54	walk->data += offset;
20036252 HX	55
23a75eee SÖ	56	if (offset & alignmask) {
23a75eee SÖ	57	unsigned int unaligned = alignmask + 1 - (offset & alignmask);
b516d514	58
23a75eee SÖ	59	if (nbytes > unaligned)
	60	nbytes = unaligned;
	61	}
20036252 HX	62
	63	walk->entrylen -= nbytes;
	64	return nbytes;
	65	}
	66
	67	static int hash_walk_new_entry(struct crypto_hash_walk *walk)
	68	{
	69	struct scatterlist *sg;
	70
	71	sg = walk->sg;
20036252	72	walk->offset = sg->offset;
13f4bb78 HX	73	walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
13f4bb78 HX	74	walk->offset = offset_in_page(walk->offset);
20036252 HX	75	walk->entrylen = sg->length;
	76
	77	if (walk->entrylen > walk->total)
	78	walk->entrylen = walk->total;
	79	walk->total -= walk->entrylen;
	80
	81	return hash_walk_next(walk);
	82	}
	83
	84	int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
	85	{
	86	unsigned int alignmask = walk->alignmask;
	87	unsigned int nbytes = walk->entrylen;
	88
	89	walk->data -= walk->offset;
	90
	91	if (nbytes && walk->offset & alignmask && !err) {
20036252 HX	92	walk->offset = ALIGN(walk->offset, alignmask + 1);
	93	walk->data += walk->offset;
	94
	95	nbytes = min(nbytes,
	96	((unsigned int)(PAGE_SIZE)) - walk->offset);
	97	walk->entrylen -= nbytes;
	98
	99	return nbytes;
	100	}
	101
75ecb231 HX	102	if (walk->flags & CRYPTO_ALG_ASYNC)
	103	kunmap(walk->pg);
	104	else {
	105	kunmap_atomic(walk->data);
	106	/*
	107	* The may sleep test only makes sense for sync users.
	108	* Async users don't need to sleep here anyway.
	109	*/
	110	crypto_yield(walk->flags);
	111	}
20036252 HX	112
	113	if (err)
	114	return err;
	115
d315a0e0 HX	116	if (nbytes) {
	117	walk->offset = 0;
	118	walk->pg++;
20036252	119	return hash_walk_next(walk);
d315a0e0	120	}
20036252 HX	121
	122	if (!walk->total)
	123	return 0;
	124
5be4d4c9	125	walk->sg = sg_next(walk->sg);
20036252 HX	126
	127	return hash_walk_new_entry(walk);
	128	}
	129	EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
	130
	131	int crypto_hash_walk_first(struct ahash_request *req,
	132	struct crypto_hash_walk *walk)
	133	{
	134	walk->total = req->nbytes;
	135
6d9529c5 TC	136	if (!walk->total) {
6d9529c5 TC	137	walk->entrylen = 0;
20036252	138	return 0;
6d9529c5	139	}
20036252 HX	140
	141	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	142	walk->sg = req->src;
75ecb231	143	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
20036252 HX	144
	145	return hash_walk_new_entry(walk);
	146	}
	147	EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
	148
75ecb231 HX	149	int crypto_ahash_walk_first(struct ahash_request *req,
	150	struct crypto_hash_walk *walk)
	151	{
	152	walk->total = req->nbytes;
	153
6d9529c5 TC	154	if (!walk->total) {
6d9529c5 TC	155	walk->entrylen = 0;
75ecb231	156	return 0;
6d9529c5	157	}
75ecb231 HX	158
	159	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	160	walk->sg = req->src;
	161	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
	162	walk->flags \|= CRYPTO_ALG_ASYNC;
	163
	164	BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
	165
	166	return hash_walk_new_entry(walk);
	167	}
	168	EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
	169
004a403c LH	170	static int ahash_setkey_unaligned(struct crypto_ahash tfm, const u8 key,
	171	unsigned int keylen)
	172	{
004a403c LH	173	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	174	int ret;
	175	u8 buffer, alignbuffer;
	176	unsigned long absize;
	177
	178	absize = keylen + alignmask;
093900c2	179	buffer = kmalloc(absize, GFP_KERNEL);
004a403c LH	180	if (!buffer)
	181	return -ENOMEM;
	182
	183	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	184	memcpy(alignbuffer, key, keylen);
a70c5225	185	ret = tfm->setkey(tfm, alignbuffer, keylen);
8c32c516	186	kzfree(buffer);
004a403c LH	187	return ret;
	188	}
	189
66f6ce5e	190	int crypto_ahash_setkey(struct crypto_ahash tfm, const u8 key,
004a403c LH	191	unsigned int keylen)
004a403c LH	192	{
004a403c LH	193	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	194
	195	if ((unsigned long)key & alignmask)
	196	return ahash_setkey_unaligned(tfm, key, keylen);
	197
a70c5225	198	return tfm->setkey(tfm, key, keylen);
004a403c	199	}
66f6ce5e	200	EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
004a403c	201
3751f402 HX	202	static int ahash_nosetkey(struct crypto_ahash tfm, const u8 key,
	203	unsigned int keylen)
	204	{
	205	return -ENOSYS;
	206	}
	207
66f6ce5e HX	208	static inline unsigned int ahash_align_buffer_size(unsigned len,
	209	unsigned long mask)
	210	{
	211	return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
	212	}
	213
1ffc9fbd	214	static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
66f6ce5e HX	215	{
	216	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	217	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	218	unsigned int ds = crypto_ahash_digestsize(tfm);
	219	struct ahash_request_priv *priv;
66f6ce5e HX	220
	221	priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
	222	(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
5befbd5a	223	GFP_KERNEL : GFP_ATOMIC);
66f6ce5e HX	224	if (!priv)
	225	return -ENOMEM;
	226
ab6bf4e5 MV	227	/*
	228	* WARNING: Voodoo programming below!
	229	*
	230	* The code below is obscure and hard to understand, thus explanation
	231	* is necessary. See include/crypto/hash.h and include/linux/crypto.h
	232	* to understand the layout of structures used here!
	233	*
	234	* The code here will replace portions of the ORIGINAL request with
	235	* pointers to new code and buffers so the hashing operation can store
	236	* the result in aligned buffer. We will call the modified request
	237	* an ADJUSTED request.
	238	*
	239	* The newly mangled request will look as such:
	240	*
	241	* req {
	242	* .result = ADJUSTED[new aligned buffer]
	243	* .base.complete = ADJUSTED[pointer to completion function]
	244	* .base.data = ADJUSTED[*req (pointer to self)]
	245	* .priv = ADJUSTED[new priv] {
	246	* .result = ORIGINAL(result)
	247	* .complete = ORIGINAL(base.complete)
	248	* .data = ORIGINAL(base.data)
	249	* }
	250	*/
	251
66f6ce5e HX	252	priv->result = req->result;
	253	priv->complete = req->base.complete;
	254	priv->data = req->base.data;
ab6bf4e5 MV	255	/*
	256	* WARNING: We do not backup req->priv here! The req->priv
	257	* is for internal use of the Crypto API and the
	258	* user must _NOT_ _EVER_ depend on it's content!
	259	*/
66f6ce5e HX	260
66f6ce5e HX	261	req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
1ffc9fbd	262	req->base.complete = cplt;
66f6ce5e HX	263	req->base.data = req;
	264	req->priv = priv;
	265
1ffc9fbd MV	266	return 0;
	267	}
	268
	269	static void ahash_restore_req(struct ahash_request *req)
	270	{
	271	struct ahash_request_priv *priv = req->priv;
	272
	273	/* Restore the original crypto request. */
	274	req->result = priv->result;
	275	req->base.complete = priv->complete;
	276	req->base.data = priv->data;
	277	req->priv = NULL;
	278
	279	/* Free the req->priv.priv from the ADJUSTED request. */
	280	kzfree(priv);
	281	}
	282
	283	static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
	284	{
	285	struct ahash_request_priv *priv = req->priv;
	286
	287	if (err == -EINPROGRESS)
	288	return;
	289
	290	if (!err)
	291	memcpy(priv->result, req->result,
	292	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	293
	294	ahash_restore_req(req);
	295	}
	296
	297	static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
	298	{
	299	struct ahash_request *areq = req->data;
	300
	301	/*
	302	* Restore the original request, see ahash_op_unaligned() for what
	303	* goes where.
	304	*
	305	* The "struct ahash_request *req" here is in fact the "req.base"
	306	* from the ADJUSTED request from ahash_op_unaligned(), thus as it
	307	* is a pointer to self, it is also the ADJUSTED "req" .
	308	*/
	309
	310	/* First copy req->result into req->priv.result */
	311	ahash_op_unaligned_finish(areq, err);
	312
	313	/* Complete the ORIGINAL request. */
	314	areq->base.complete(&areq->base, err);
	315	}
	316
	317	static int ahash_op_unaligned(struct ahash_request *req,
	318	int (op)(struct ahash_request ))
	319	{
	320	int err;
	321
	322	err = ahash_save_req(req, ahash_op_unaligned_done);
	323	if (err)
	324	return err;
	325
66f6ce5e HX	326	err = op(req);
	327	ahash_op_unaligned_finish(req, err);
	328
	329	return err;
	330	}
	331
	332	static int crypto_ahash_op(struct ahash_request *req,
	333	int (op)(struct ahash_request ))
	334	{
	335	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	336	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	337
	338	if ((unsigned long)req->result & alignmask)
	339	return ahash_op_unaligned(req, op);
	340
	341	return op(req);
	342	}
	343
	344	int crypto_ahash_final(struct ahash_request *req)
	345	{
	346	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
	347	}
	348	EXPORT_SYMBOL_GPL(crypto_ahash_final);
	349
	350	int crypto_ahash_finup(struct ahash_request *req)
	351	{
	352	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
	353	}
	354	EXPORT_SYMBOL_GPL(crypto_ahash_finup);
	355
	356	int crypto_ahash_digest(struct ahash_request *req)
	357	{
	358	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
	359	}
	360	EXPORT_SYMBOL_GPL(crypto_ahash_digest);
	361
	362	static void ahash_def_finup_finish2(struct ahash_request *req, int err)
	363	{
	364	struct ahash_request_priv *priv = req->priv;
	365
	366	if (err == -EINPROGRESS)
	367	return;
	368
	369	if (!err)
	370	memcpy(priv->result, req->result,
	371	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	372
d4a7a0fb	373	ahash_restore_req(req);
66f6ce5e HX	374	}
	375
	376	static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
	377	{
	378	struct ahash_request *areq = req->data;
66f6ce5e HX	379
	380	ahash_def_finup_finish2(areq, err);
	381
d4a7a0fb	382	areq->base.complete(&areq->base, err);
66f6ce5e HX	383	}
	384
	385	static int ahash_def_finup_finish1(struct ahash_request *req, int err)
	386	{
	387	if (err)
	388	goto out;
	389
	390	req->base.complete = ahash_def_finup_done2;
	391	req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	392	err = crypto_ahash_reqtfm(req)->final(req);
	393
	394	out:
	395	ahash_def_finup_finish2(req, err);
	396	return err;
	397	}
	398
	399	static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
	400	{
	401	struct ahash_request *areq = req->data;
66f6ce5e HX	402
	403	err = ahash_def_finup_finish1(areq, err);
	404
d4a7a0fb	405	areq->base.complete(&areq->base, err);
66f6ce5e HX	406	}
	407
	408	static int ahash_def_finup(struct ahash_request *req)
	409	{
	410	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
d4a7a0fb	411	int err;
66f6ce5e	412
d4a7a0fb MV	413	err = ahash_save_req(req, ahash_def_finup_done1);
	414	if (err)
	415	return err;
66f6ce5e	416
d4a7a0fb MV	417	err = tfm->update(req);
d4a7a0fb MV	418	return ahash_def_finup_finish1(req, err);
66f6ce5e HX	419	}
	420
	421	static int ahash_no_export(struct ahash_request req, void out)
	422	{
	423	return -ENOSYS;
	424	}
	425
	426	static int ahash_no_import(struct ahash_request req, const void in)
	427	{
	428	return -ENOSYS;
	429	}
	430
88056ec3 HX	431	static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
	432	{
	433	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
	434	struct ahash_alg *alg = crypto_ahash_alg(hash);
88056ec3	435
66f6ce5e	436	hash->setkey = ahash_nosetkey;
a5596d63	437	hash->has_setkey = false;
66f6ce5e HX	438	hash->export = ahash_no_export;
	439	hash->import = ahash_no_import;
	440
88056ec3 HX	441	if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
	442	return crypto_init_shash_ops_async(tfm);
	443
88056ec3 HX	444	hash->init = alg->init;
88056ec3 HX	445	hash->update = alg->update;
66f6ce5e HX	446	hash->final = alg->final;
66f6ce5e HX	447	hash->finup = alg->finup ?: ahash_def_finup;
88056ec3	448	hash->digest = alg->digest;
66f6ce5e	449
a5596d63	450	if (alg->setkey) {
66f6ce5e	451	hash->setkey = alg->setkey;
a5596d63 HX	452	hash->has_setkey = true;
a5596d63 HX	453	}
66f6ce5e HX	454	if (alg->export)
	455	hash->export = alg->export;
	456	if (alg->import)
	457	hash->import = alg->import;
88056ec3 HX	458
	459	return 0;
	460	}
	461
	462	static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
	463	{
	464	if (alg->cra_type == &crypto_ahash_type)
	465	return alg->cra_ctxsize;
	466
	467	return sizeof(struct crypto_shash *);
	468	}
	469
3acc8473	470	#ifdef CONFIG_NET
6238cbae SK	471	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	472	{
	473	struct crypto_report_hash rhash;
	474
9a5467bf	475	strncpy(rhash.type, "ahash", sizeof(rhash.type));
6238cbae SK	476
	477	rhash.blocksize = alg->cra_blocksize;
	478	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
	479
6662df33 DM	480	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
	481	sizeof(struct crypto_report_hash), &rhash))
	482	goto nla_put_failure;
6238cbae SK	483	return 0;
	484
	485	nla_put_failure:
	486	return -EMSGSIZE;
	487	}
3acc8473 HX	488	#else
	489	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	490	{
	491	return -ENOSYS;
	492	}
	493	#endif
6238cbae	494
004a403c LH	495	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	496	__attribute__ ((unused));
	497	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	498	{
	499	seq_printf(m, "type : ahash\n");
	500	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
	501	"yes" : "no");
	502	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
88056ec3 HX	503	seq_printf(m, "digestsize : %u\n",
88056ec3 HX	504	__crypto_hash_alg_common(alg)->digestsize);
004a403c LH	505	}
	506
	507	const struct crypto_type crypto_ahash_type = {
88056ec3 HX	508	.extsize = crypto_ahash_extsize,
88056ec3 HX	509	.init_tfm = crypto_ahash_init_tfm,
004a403c LH	510	#ifdef CONFIG_PROC_FS
	511	.show = crypto_ahash_show,
	512	#endif
6238cbae	513	.report = crypto_ahash_report,
88056ec3 HX	514	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	515	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	516	.type = CRYPTO_ALG_TYPE_AHASH,
	517	.tfmsize = offsetof(struct crypto_ahash, base),
004a403c LH	518	};
	519	EXPORT_SYMBOL_GPL(crypto_ahash_type);
	520
88056ec3 HX	521	struct crypto_ahash crypto_alloc_ahash(const char alg_name, u32 type,
	522	u32 mask)
	523	{
	524	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
	525	}
	526	EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
	527
8d18e34c HX	528	int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
	529	{
	530	return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
	531	}
	532	EXPORT_SYMBOL_GPL(crypto_has_ahash);
	533
01c2dece HX	534	static int ahash_prepare_alg(struct ahash_alg *alg)
	535	{
	536	struct crypto_alg *base = &alg->halg.base;
	537
	538	if (alg->halg.digestsize > PAGE_SIZE / 8 \|\|
8996eafd RK	539	alg->halg.statesize > PAGE_SIZE / 8 \|\|
8996eafd RK	540	alg->halg.statesize == 0)
01c2dece HX	541	return -EINVAL;
	542
	543	base->cra_type = &crypto_ahash_type;
	544	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	545	base->cra_flags \|= CRYPTO_ALG_TYPE_AHASH;
	546
	547	return 0;
	548	}
	549
	550	int crypto_register_ahash(struct ahash_alg *alg)
	551	{
	552	struct crypto_alg *base = &alg->halg.base;
	553	int err;
	554
	555	err = ahash_prepare_alg(alg);
	556	if (err)
	557	return err;
	558
	559	return crypto_register_alg(base);
	560	}
	561	EXPORT_SYMBOL_GPL(crypto_register_ahash);
	562
	563	int crypto_unregister_ahash(struct ahash_alg *alg)
	564	{
	565	return crypto_unregister_alg(&alg->halg.base);
	566	}
	567	EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
	568
	569	int ahash_register_instance(struct crypto_template *tmpl,
	570	struct ahash_instance *inst)
	571	{
	572	int err;
	573
	574	err = ahash_prepare_alg(&inst->alg);
	575	if (err)
	576	return err;
	577
	578	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
	579	}
	580	EXPORT_SYMBOL_GPL(ahash_register_instance);
	581
	582	void ahash_free_instance(struct crypto_instance *inst)
	583	{
	584	crypto_drop_spawn(crypto_instance_ctx(inst));
	585	kfree(ahash_instance(inst));
	586	}
	587	EXPORT_SYMBOL_GPL(ahash_free_instance);
	588
	589	int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
	590	struct hash_alg_common *alg,
	591	struct crypto_instance *inst)
	592	{
	593	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
	594	&crypto_ahash_type);
	595	}
	596	EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
	597
	598	struct hash_alg_common ahash_attr_alg(struct rtattr rta, u32 type, u32 mask)
	599	{
	600	struct crypto_alg *alg;
	601
	602	alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
	603	return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
	604	}
605	EXPORT_SYMBOL_GPL(ahash_attr_alg);
606
004a403c LH	607	MODULE_LICENSE("GPL");
004a403c LH	608	MODULE_DESCRIPTION("Asynchronous cryptographic hash type");