[linux.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 <[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 <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 <linux/compiler.h>
#include <net/netlink.h>

#include "internal.h"

struct ahash_request_priv {
	crypto_completion_t complete;
	void *data;
	u8 *result;
	u32 flags;
	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);
		nbytes = min(nbytes,
			     ((unsigned int)(PAGE_SIZE)) - walk->offset);
		walk->entrylen -= nbytes;

		if (nbytes) {
			walk->data += walk->offset;
			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);
	int err;

	if ((unsigned long)key & alignmask)
		err = ahash_setkey_unaligned(tfm, key, keylen);
	else
		err = tfm->setkey(tfm, key, keylen);

	if (err)
		return err;

	crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
	return 0;
}
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;
	priv->flags = req->base.flags;

	/*
	 * 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, int err)
{
	struct ahash_request_priv *priv = req->priv;

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

	/* Restore the original crypto request. */
	req->result = priv->result;

	ahash_request_set_callback(req, priv->flags,
				   priv->complete, priv->data);
	req->priv = NULL;

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

static void ahash_notify_einprogress(struct ahash_request *req)
{
	struct ahash_request_priv *priv = req->priv;
	struct crypto_async_request oreq;

	oreq.data = priv->data;

	priv->complete(&oreq, -EINPROGRESS);
}

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

	if (err == -EINPROGRESS) {
		ahash_notify_einprogress(areq);
		return;
	}

	/*
	 * 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_restore_req(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);
	if (err == -EINPROGRESS || err == -EBUSY)
		return err;

	ahash_restore_req(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)
{
	int ret;

	ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
	crypto_stat_ahash_final(req, ret);
	return ret;
}
EXPORT_SYMBOL_GPL(crypto_ahash_final);

int crypto_ahash_finup(struct ahash_request *req)
{
	int ret;

	ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
	crypto_stat_ahash_final(req, ret);
	return ret;
}
EXPORT_SYMBOL_GPL(crypto_ahash_finup);

int crypto_ahash_digest(struct ahash_request *req)
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	int ret;

	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
		ret = -ENOKEY;
	else
		ret = crypto_ahash_op(req, tfm->digest);
	crypto_stat_ahash_final(req, ret);
	return ret;
}
EXPORT_SYMBOL_GPL(crypto_ahash_digest);

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

	if (err == -EINPROGRESS)
		return;

	ahash_restore_req(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;

	err = crypto_ahash_reqtfm(req)->final(req);
	if (err == -EINPROGRESS || err == -EBUSY)
		return err;

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

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

	if (err == -EINPROGRESS) {
		ahash_notify_einprogress(areq);
		return;
	}

	areq->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	err = ahash_def_finup_finish1(areq, err);
	if (areq->priv)
		return;

	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);
	if (err == -EINPROGRESS || err == -EBUSY)
		return err;

	return ahash_def_finup_finish1(req, err);
}

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;

	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;
	hash->export = alg->export;
	hash->import = alg->import;

	if (alg->setkey) {
		hash->setkey = alg->setkey;
		if (!(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
			crypto_ahash_set_flags(hash, CRYPTO_TFM_NEED_KEY);
	}

	return 0;
}

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

	return crypto_alg_extsize(alg);
}

#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)
	__maybe_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 > HASH_MAX_DIGESTSIZE ||
	    alg->halg.statesize > HASH_MAX_STATESIZE ||
	    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 crypto_register_ahashes(struct ahash_alg *algs, int count)
{
	int i, ret;

	for (i = 0; i < count; i++) {
		ret = crypto_register_ahash(&algs[i]);
		if (ret)
			goto err;
	}

	return 0;

err:
	for (--i; i >= 0; --i)
		crypto_unregister_ahash(&algs[i]);

	return ret;
}
EXPORT_SYMBOL_GPL(crypto_register_ahashes);

void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
{
	int i;

	for (i = count - 1; i >= 0; --i)
		crypto_unregister_ahash(&algs[i]);
}
EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);

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);

bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
{
	struct crypto_alg *alg = &halg->base;

	if (alg->cra_type != &crypto_ahash_type)
		return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));

	return __crypto_ahash_alg(alg)->setkey != NULL;
}
EXPORT_SYMBOL_GPL(crypto_hash_alg_has_setkey);

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 <[email protected]>
	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	25	#include <linux/cryptouser.h>
d8c34b94	26	#include <linux/compiler.h>
6238cbae	27	#include <net/netlink.h>
004a403c LH	28
	29	#include "internal.h"
	30
66f6ce5e HX	31	struct ahash_request_priv {
	32	crypto_completion_t complete;
	33	void *data;
	34	u8 *result;
ef0579b6	35	u32 flags;
66f6ce5e HX	36	void *ubuf[] CRYPTO_MINALIGN_ATTR;
	37	};
	38
88056ec3 HX	39	static inline struct ahash_alg crypto_ahash_alg(struct crypto_ahash hash)
	40	{
	41	return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
	42	halg);
	43	}
	44
20036252 HX	45	static int hash_walk_next(struct crypto_hash_walk *walk)
	46	{
	47	unsigned int alignmask = walk->alignmask;
	48	unsigned int offset = walk->offset;
	49	unsigned int nbytes = min(walk->entrylen,
	50	((unsigned int)(PAGE_SIZE)) - offset);
	51
75ecb231 HX	52	if (walk->flags & CRYPTO_ALG_ASYNC)
	53	walk->data = kmap(walk->pg);
	54	else
	55	walk->data = kmap_atomic(walk->pg);
20036252 HX	56	walk->data += offset;
20036252 HX	57
23a75eee SÖ	58	if (offset & alignmask) {
23a75eee SÖ	59	unsigned int unaligned = alignmask + 1 - (offset & alignmask);
b516d514	60
23a75eee SÖ	61	if (nbytes > unaligned)
	62	nbytes = unaligned;
	63	}
20036252 HX	64
	65	walk->entrylen -= nbytes;
	66	return nbytes;
	67	}
	68
	69	static int hash_walk_new_entry(struct crypto_hash_walk *walk)
	70	{
	71	struct scatterlist *sg;
	72
	73	sg = walk->sg;
20036252	74	walk->offset = sg->offset;
13f4bb78 HX	75	walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
13f4bb78 HX	76	walk->offset = offset_in_page(walk->offset);
20036252 HX	77	walk->entrylen = sg->length;
	78
	79	if (walk->entrylen > walk->total)
	80	walk->entrylen = walk->total;
	81	walk->total -= walk->entrylen;
	82
	83	return hash_walk_next(walk);
	84	}
	85
	86	int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
	87	{
	88	unsigned int alignmask = walk->alignmask;
	89	unsigned int nbytes = walk->entrylen;
	90
	91	walk->data -= walk->offset;
	92
	93	if (nbytes && walk->offset & alignmask && !err) {
20036252	94	walk->offset = ALIGN(walk->offset, alignmask + 1);
20036252 HX	95	nbytes = min(nbytes,
	96	((unsigned int)(PAGE_SIZE)) - walk->offset);
	97	walk->entrylen -= nbytes;
	98
900a081f HX	99	if (nbytes) {
	100	walk->data += walk->offset;
	101	return nbytes;
	102	}
20036252 HX	103	}
20036252 HX	104
75ecb231 HX	105	if (walk->flags & CRYPTO_ALG_ASYNC)
	106	kunmap(walk->pg);
	107	else {
	108	kunmap_atomic(walk->data);
	109	/*
	110	* The may sleep test only makes sense for sync users.
	111	* Async users don't need to sleep here anyway.
	112	*/
	113	crypto_yield(walk->flags);
	114	}
20036252 HX	115
	116	if (err)
	117	return err;
	118
d315a0e0 HX	119	if (nbytes) {
	120	walk->offset = 0;
	121	walk->pg++;
20036252	122	return hash_walk_next(walk);
d315a0e0	123	}
20036252 HX	124
	125	if (!walk->total)
	126	return 0;
	127
5be4d4c9	128	walk->sg = sg_next(walk->sg);
20036252 HX	129
	130	return hash_walk_new_entry(walk);
	131	}
	132	EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
	133
	134	int crypto_hash_walk_first(struct ahash_request *req,
	135	struct crypto_hash_walk *walk)
	136	{
	137	walk->total = req->nbytes;
	138
6d9529c5 TC	139	if (!walk->total) {
6d9529c5 TC	140	walk->entrylen = 0;
20036252	141	return 0;
6d9529c5	142	}
20036252 HX	143
	144	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	145	walk->sg = req->src;
75ecb231	146	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
20036252 HX	147
	148	return hash_walk_new_entry(walk);
	149	}
	150	EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
	151
75ecb231 HX	152	int crypto_ahash_walk_first(struct ahash_request *req,
	153	struct crypto_hash_walk *walk)
	154	{
	155	walk->total = req->nbytes;
	156
6d9529c5 TC	157	if (!walk->total) {
6d9529c5 TC	158	walk->entrylen = 0;
75ecb231	159	return 0;
6d9529c5	160	}
75ecb231 HX	161
	162	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	163	walk->sg = req->src;
	164	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
	165	walk->flags \|= CRYPTO_ALG_ASYNC;
	166
	167	BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
	168
	169	return hash_walk_new_entry(walk);
	170	}
	171	EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
	172
004a403c LH	173	static int ahash_setkey_unaligned(struct crypto_ahash tfm, const u8 key,
	174	unsigned int keylen)
	175	{
004a403c LH	176	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	177	int ret;
	178	u8 buffer, alignbuffer;
	179	unsigned long absize;
	180
	181	absize = keylen + alignmask;
093900c2	182	buffer = kmalloc(absize, GFP_KERNEL);
004a403c LH	183	if (!buffer)
	184	return -ENOMEM;
	185
	186	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	187	memcpy(alignbuffer, key, keylen);
a70c5225	188	ret = tfm->setkey(tfm, alignbuffer, keylen);
8c32c516	189	kzfree(buffer);
004a403c LH	190	return ret;
	191	}
	192
66f6ce5e	193	int crypto_ahash_setkey(struct crypto_ahash tfm, const u8 key,
004a403c LH	194	unsigned int keylen)
004a403c LH	195	{
004a403c	196	unsigned long alignmask = crypto_ahash_alignmask(tfm);
9fa68f62	197	int err;
004a403c LH	198
004a403c LH	199	if ((unsigned long)key & alignmask)
9fa68f62 EB	200	err = ahash_setkey_unaligned(tfm, key, keylen);
	201	else
	202	err = tfm->setkey(tfm, key, keylen);
	203
	204	if (err)
	205	return err;
004a403c	206
9fa68f62 EB	207	crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
9fa68f62 EB	208	return 0;
004a403c	209	}
66f6ce5e	210	EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
004a403c	211
3751f402 HX	212	static int ahash_nosetkey(struct crypto_ahash tfm, const u8 key,
	213	unsigned int keylen)
	214	{
	215	return -ENOSYS;
	216	}
	217
66f6ce5e HX	218	static inline unsigned int ahash_align_buffer_size(unsigned len,
	219	unsigned long mask)
	220	{
	221	return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
	222	}
	223
1ffc9fbd	224	static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
66f6ce5e HX	225	{
	226	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	227	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	228	unsigned int ds = crypto_ahash_digestsize(tfm);
	229	struct ahash_request_priv *priv;
66f6ce5e HX	230
	231	priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
	232	(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
5befbd5a	233	GFP_KERNEL : GFP_ATOMIC);
66f6ce5e HX	234	if (!priv)
	235	return -ENOMEM;
	236
ab6bf4e5 MV	237	/*
	238	* WARNING: Voodoo programming below!
	239	*
	240	* The code below is obscure and hard to understand, thus explanation
	241	* is necessary. See include/crypto/hash.h and include/linux/crypto.h
	242	* to understand the layout of structures used here!
	243	*
	244	* The code here will replace portions of the ORIGINAL request with
	245	* pointers to new code and buffers so the hashing operation can store
	246	* the result in aligned buffer. We will call the modified request
	247	* an ADJUSTED request.
	248	*
	249	* The newly mangled request will look as such:
	250	*
	251	* req {
	252	* .result = ADJUSTED[new aligned buffer]
	253	* .base.complete = ADJUSTED[pointer to completion function]
	254	* .base.data = ADJUSTED[*req (pointer to self)]
	255	* .priv = ADJUSTED[new priv] {
	256	* .result = ORIGINAL(result)
	257	* .complete = ORIGINAL(base.complete)
	258	* .data = ORIGINAL(base.data)
	259	* }
	260	*/
	261
66f6ce5e HX	262	priv->result = req->result;
	263	priv->complete = req->base.complete;
	264	priv->data = req->base.data;
ef0579b6 HX	265	priv->flags = req->base.flags;
ef0579b6 HX	266
ab6bf4e5 MV	267	/*
	268	* WARNING: We do not backup req->priv here! The req->priv
	269	* is for internal use of the Crypto API and the
	270	* user must _NOT_ _EVER_ depend on it's content!
	271	*/
66f6ce5e HX	272
66f6ce5e HX	273	req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
1ffc9fbd	274	req->base.complete = cplt;
66f6ce5e HX	275	req->base.data = req;
	276	req->priv = priv;
	277
1ffc9fbd MV	278	return 0;
	279	}
	280
ef0579b6	281	static void ahash_restore_req(struct ahash_request *req, int err)
1ffc9fbd MV	282	{
	283	struct ahash_request_priv *priv = req->priv;
	284
ef0579b6 HX	285	if (!err)
	286	memcpy(priv->result, req->result,
	287	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	288
1ffc9fbd MV	289	/* Restore the original crypto request. */
1ffc9fbd MV	290	req->result = priv->result;
ef0579b6 HX	291
	292	ahash_request_set_callback(req, priv->flags,
	293	priv->complete, priv->data);
1ffc9fbd MV	294	req->priv = NULL;
	295
	296	/* Free the req->priv.priv from the ADJUSTED request. */
	297	kzfree(priv);
	298	}
	299
ef0579b6	300	static void ahash_notify_einprogress(struct ahash_request *req)
1ffc9fbd MV	301	{
1ffc9fbd MV	302	struct ahash_request_priv *priv = req->priv;
ef0579b6	303	struct crypto_async_request oreq;
1ffc9fbd	304
ef0579b6	305	oreq.data = priv->data;
1ffc9fbd	306
ef0579b6	307	priv->complete(&oreq, -EINPROGRESS);
1ffc9fbd MV	308	}
	309
	310	static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
	311	{
	312	struct ahash_request *areq = req->data;
	313
ef0579b6 HX	314	if (err == -EINPROGRESS) {
	315	ahash_notify_einprogress(areq);
	316	return;
	317	}
	318
1ffc9fbd MV	319	/*
	320	* Restore the original request, see ahash_op_unaligned() for what
	321	* goes where.
	322	*
	323	* The "struct ahash_request *req" here is in fact the "req.base"
	324	* from the ADJUSTED request from ahash_op_unaligned(), thus as it
	325	* is a pointer to self, it is also the ADJUSTED "req" .
	326	*/
	327
	328	/* First copy req->result into req->priv.result */
ef0579b6	329	ahash_restore_req(areq, err);
1ffc9fbd MV	330
	331	/* Complete the ORIGINAL request. */
	332	areq->base.complete(&areq->base, err);
	333	}
	334
	335	static int ahash_op_unaligned(struct ahash_request *req,
	336	int (op)(struct ahash_request ))
	337	{
	338	int err;
	339
	340	err = ahash_save_req(req, ahash_op_unaligned_done);
	341	if (err)
	342	return err;
	343
66f6ce5e	344	err = op(req);
4e5b0ad5	345	if (err == -EINPROGRESS \|\| err == -EBUSY)
ef0579b6 HX	346	return err;
	347
	348	ahash_restore_req(req, err);
66f6ce5e HX	349
	350	return err;
	351	}
	352
	353	static int crypto_ahash_op(struct ahash_request *req,
	354	int (op)(struct ahash_request ))
	355	{
	356	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	357	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	358
	359	if ((unsigned long)req->result & alignmask)
	360	return ahash_op_unaligned(req, op);
	361
	362	return op(req);
	363	}
	364
	365	int crypto_ahash_final(struct ahash_request *req)
	366	{
cac5818c CL	367	int ret;
	368
	369	ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
	370	crypto_stat_ahash_final(req, ret);
	371	return ret;
66f6ce5e HX	372	}
	373	EXPORT_SYMBOL_GPL(crypto_ahash_final);
	374
	375	int crypto_ahash_finup(struct ahash_request *req)
	376	{
cac5818c CL	377	int ret;
	378
	379	ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
	380	crypto_stat_ahash_final(req, ret);
	381	return ret;
66f6ce5e HX	382	}
	383	EXPORT_SYMBOL_GPL(crypto_ahash_finup);
	384
	385	int crypto_ahash_digest(struct ahash_request *req)
	386	{
9fa68f62	387	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
cac5818c	388	int ret;
9fa68f62 EB	389
9fa68f62 EB	390	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
cac5818c CL	391	ret = -ENOKEY;
	392	else
	393	ret = crypto_ahash_op(req, tfm->digest);
	394	crypto_stat_ahash_final(req, ret);
	395	return ret;
66f6ce5e HX	396	}
	397	EXPORT_SYMBOL_GPL(crypto_ahash_digest);
	398
ef0579b6	399	static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
66f6ce5e	400	{
ef0579b6	401	struct ahash_request *areq = req->data;
66f6ce5e HX	402
	403	if (err == -EINPROGRESS)
	404	return;
	405
ef0579b6	406	ahash_restore_req(areq, err);
66f6ce5e	407
d4a7a0fb	408	areq->base.complete(&areq->base, err);
66f6ce5e HX	409	}
	410
	411	static int ahash_def_finup_finish1(struct ahash_request *req, int err)
	412	{
	413	if (err)
	414	goto out;
	415
	416	req->base.complete = ahash_def_finup_done2;
ef0579b6	417
66f6ce5e	418	err = crypto_ahash_reqtfm(req)->final(req);
4e5b0ad5	419	if (err == -EINPROGRESS \|\| err == -EBUSY)
ef0579b6	420	return err;
66f6ce5e HX	421
66f6ce5e HX	422	out:
ef0579b6	423	ahash_restore_req(req, err);
66f6ce5e HX	424	return err;
	425	}
	426
	427	static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
	428	{
	429	struct ahash_request *areq = req->data;
66f6ce5e	430
ef0579b6 HX	431	if (err == -EINPROGRESS) {
	432	ahash_notify_einprogress(areq);
	433	return;
	434	}
	435
	436	areq->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	437
66f6ce5e	438	err = ahash_def_finup_finish1(areq, err);
ef0579b6 HX	439	if (areq->priv)
ef0579b6 HX	440	return;
66f6ce5e	441
d4a7a0fb	442	areq->base.complete(&areq->base, err);
66f6ce5e HX	443	}
	444
	445	static int ahash_def_finup(struct ahash_request *req)
	446	{
	447	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
d4a7a0fb	448	int err;
66f6ce5e	449
d4a7a0fb MV	450	err = ahash_save_req(req, ahash_def_finup_done1);
	451	if (err)
	452	return err;
66f6ce5e	453
d4a7a0fb	454	err = tfm->update(req);
4e5b0ad5	455	if (err == -EINPROGRESS \|\| err == -EBUSY)
ef0579b6 HX	456	return err;
ef0579b6 HX	457
d4a7a0fb	458	return ahash_def_finup_finish1(req, err);
66f6ce5e HX	459	}
66f6ce5e HX	460
88056ec3 HX	461	static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
	462	{
	463	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
	464	struct ahash_alg *alg = crypto_ahash_alg(hash);
88056ec3	465
66f6ce5e	466	hash->setkey = ahash_nosetkey;
66f6ce5e	467
88056ec3 HX	468	if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
	469	return crypto_init_shash_ops_async(tfm);
	470
88056ec3 HX	471	hash->init = alg->init;
88056ec3 HX	472	hash->update = alg->update;
66f6ce5e HX	473	hash->final = alg->final;
66f6ce5e HX	474	hash->finup = alg->finup ?: ahash_def_finup;
88056ec3	475	hash->digest = alg->digest;
6f221f7e KK	476	hash->export = alg->export;
6f221f7e KK	477	hash->import = alg->import;
66f6ce5e	478
a5596d63	479	if (alg->setkey) {
66f6ce5e	480	hash->setkey = alg->setkey;
9fa68f62 EB	481	if (!(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
9fa68f62 EB	482	crypto_ahash_set_flags(hash, CRYPTO_TFM_NEED_KEY);
a5596d63	483	}
88056ec3 HX	484
	485	return 0;
	486	}
	487
	488	static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
	489	{
2495cf25 HX	490	if (alg->cra_type != &crypto_ahash_type)
2495cf25 HX	491	return sizeof(struct crypto_shash *);
88056ec3	492
2495cf25	493	return crypto_alg_extsize(alg);
88056ec3 HX	494	}
88056ec3 HX	495
3acc8473	496	#ifdef CONFIG_NET
6238cbae SK	497	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	498	{
	499	struct crypto_report_hash rhash;
	500
9a5467bf	501	strncpy(rhash.type, "ahash", sizeof(rhash.type));
6238cbae SK	502
	503	rhash.blocksize = alg->cra_blocksize;
	504	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
	505
6662df33 DM	506	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
	507	sizeof(struct crypto_report_hash), &rhash))
	508	goto nla_put_failure;
6238cbae SK	509	return 0;
	510
	511	nla_put_failure:
	512	return -EMSGSIZE;
	513	}
3acc8473 HX	514	#else
	515	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	516	{
	517	return -ENOSYS;
	518	}
	519	#endif
6238cbae	520
004a403c	521	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
d8c34b94	522	__maybe_unused;
004a403c LH	523	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	524	{
	525	seq_printf(m, "type : ahash\n");
	526	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
	527	"yes" : "no");
	528	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
88056ec3 HX	529	seq_printf(m, "digestsize : %u\n",
88056ec3 HX	530	__crypto_hash_alg_common(alg)->digestsize);
004a403c LH	531	}
	532
	533	const struct crypto_type crypto_ahash_type = {
88056ec3 HX	534	.extsize = crypto_ahash_extsize,
88056ec3 HX	535	.init_tfm = crypto_ahash_init_tfm,
004a403c LH	536	#ifdef CONFIG_PROC_FS
	537	.show = crypto_ahash_show,
	538	#endif
6238cbae	539	.report = crypto_ahash_report,
88056ec3 HX	540	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	541	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	542	.type = CRYPTO_ALG_TYPE_AHASH,
	543	.tfmsize = offsetof(struct crypto_ahash, base),
004a403c LH	544	};
	545	EXPORT_SYMBOL_GPL(crypto_ahash_type);
	546
88056ec3 HX	547	struct crypto_ahash crypto_alloc_ahash(const char alg_name, u32 type,
	548	u32 mask)
	549	{
	550	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
	551	}
	552	EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
	553
8d18e34c HX	554	int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
	555	{
	556	return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
	557	}
	558	EXPORT_SYMBOL_GPL(crypto_has_ahash);
	559
01c2dece HX	560	static int ahash_prepare_alg(struct ahash_alg *alg)
	561	{
	562	struct crypto_alg *base = &alg->halg.base;
	563
b68a7ec1 KC	564	if (alg->halg.digestsize > HASH_MAX_DIGESTSIZE \|\|
b68a7ec1 KC	565	alg->halg.statesize > HASH_MAX_STATESIZE \|\|
8996eafd	566	alg->halg.statesize == 0)
01c2dece HX	567	return -EINVAL;
	568
	569	base->cra_type = &crypto_ahash_type;
	570	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	571	base->cra_flags \|= CRYPTO_ALG_TYPE_AHASH;
	572
	573	return 0;
	574	}
	575
	576	int crypto_register_ahash(struct ahash_alg *alg)
	577	{
	578	struct crypto_alg *base = &alg->halg.base;
	579	int err;
	580
	581	err = ahash_prepare_alg(alg);
	582	if (err)
	583	return err;
	584
	585	return crypto_register_alg(base);
	586	}
	587	EXPORT_SYMBOL_GPL(crypto_register_ahash);
	588
	589	int crypto_unregister_ahash(struct ahash_alg *alg)
	590	{
	591	return crypto_unregister_alg(&alg->halg.base);
	592	}
	593	EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
	594
6f7473c5 RV	595	int crypto_register_ahashes(struct ahash_alg *algs, int count)
	596	{
	597	int i, ret;
	598
	599	for (i = 0; i < count; i++) {
	600	ret = crypto_register_ahash(&algs[i]);
	601	if (ret)
	602	goto err;
	603	}
	604
	605	return 0;
	606
	607	err:
	608	for (--i; i >= 0; --i)
	609	crypto_unregister_ahash(&algs[i]);
	610
	611	return ret;
	612	}
	613	EXPORT_SYMBOL_GPL(crypto_register_ahashes);
	614
	615	void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
	616	{
	617	int i;
	618
	619	for (i = count - 1; i >= 0; --i)
	620	crypto_unregister_ahash(&algs[i]);
	621	}
	622	EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);
	623
01c2dece HX	624	int ahash_register_instance(struct crypto_template *tmpl,
	625	struct ahash_instance *inst)
	626	{
	627	int err;
	628
	629	err = ahash_prepare_alg(&inst->alg);
	630	if (err)
	631	return err;
	632
	633	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
	634	}
	635	EXPORT_SYMBOL_GPL(ahash_register_instance);
	636
	637	void ahash_free_instance(struct crypto_instance *inst)
	638	{
	639	crypto_drop_spawn(crypto_instance_ctx(inst));
	640	kfree(ahash_instance(inst));
	641	}
	642	EXPORT_SYMBOL_GPL(ahash_free_instance);
	643
	644	int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
	645	struct hash_alg_common *alg,
	646	struct crypto_instance *inst)
	647	{
	648	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
	649	&crypto_ahash_type);
	650	}
	651	EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
	652
	653	struct hash_alg_common ahash_attr_alg(struct rtattr rta, u32 type, u32 mask)
	654	{
	655	struct crypto_alg *alg;
	656
	657	alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
	658	return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
	659	}
	660	EXPORT_SYMBOL_GPL(ahash_attr_alg);
	661
cd6ed77a EB	662	bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
	663	{
	664	struct crypto_alg *alg = &halg->base;
	665
	666	if (alg->cra_type != &crypto_ahash_type)
	667	return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));
	668
	669	return __crypto_ahash_alg(alg)->setkey != NULL;
	670	}
	671	EXPORT_SYMBOL_GPL(crypto_hash_alg_has_setkey);
	672
004a403c LH	673	MODULE_LICENSE("GPL");
004a403c LH	674	MODULE_DESCRIPTION("Asynchronous cryptographic hash type");