[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);
		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);
	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)
{
	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)
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);

	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
		return -ENOKEY;

	return crypto_ahash_op(req, tfm->digest);
}
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 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->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;
		if (!(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
			crypto_ahash_set_flags(hash, CRYPTO_TFM_NEED_KEY);
	}
	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 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 > 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 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 HX	94	walk->offset = ALIGN(walk->offset, alignmask + 1);
	95	walk->data += walk->offset;
	96
	97	nbytes = min(nbytes,
	98	((unsigned int)(PAGE_SIZE)) - walk->offset);
	99	walk->entrylen -= nbytes;
	100
	101	return nbytes;
	102	}
	103
75ecb231 HX	104	if (walk->flags & CRYPTO_ALG_ASYNC)
	105	kunmap(walk->pg);
	106	else {
	107	kunmap_atomic(walk->data);
	108	/*
	109	* The may sleep test only makes sense for sync users.
	110	* Async users don't need to sleep here anyway.
	111	*/
	112	crypto_yield(walk->flags);
	113	}
20036252 HX	114
	115	if (err)
	116	return err;
	117
d315a0e0 HX	118	if (nbytes) {
	119	walk->offset = 0;
	120	walk->pg++;
20036252	121	return hash_walk_next(walk);
d315a0e0	122	}
20036252 HX	123
	124	if (!walk->total)
	125	return 0;
	126
5be4d4c9	127	walk->sg = sg_next(walk->sg);
20036252 HX	128
	129	return hash_walk_new_entry(walk);
	130	}
	131	EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
	132
	133	int crypto_hash_walk_first(struct ahash_request *req,
	134	struct crypto_hash_walk *walk)
	135	{
	136	walk->total = req->nbytes;
	137
6d9529c5 TC	138	if (!walk->total) {
6d9529c5 TC	139	walk->entrylen = 0;
20036252	140	return 0;
6d9529c5	141	}
20036252 HX	142
	143	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	144	walk->sg = req->src;
75ecb231	145	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
20036252 HX	146
	147	return hash_walk_new_entry(walk);
	148	}
	149	EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
	150
75ecb231 HX	151	int crypto_ahash_walk_first(struct ahash_request *req,
	152	struct crypto_hash_walk *walk)
	153	{
	154	walk->total = req->nbytes;
	155
6d9529c5 TC	156	if (!walk->total) {
6d9529c5 TC	157	walk->entrylen = 0;
75ecb231	158	return 0;
6d9529c5	159	}
75ecb231 HX	160
	161	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	162	walk->sg = req->src;
	163	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
	164	walk->flags \|= CRYPTO_ALG_ASYNC;
	165
	166	BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
	167
	168	return hash_walk_new_entry(walk);
	169	}
	170	EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
	171
004a403c LH	172	static int ahash_setkey_unaligned(struct crypto_ahash tfm, const u8 key,
	173	unsigned int keylen)
	174	{
004a403c LH	175	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	176	int ret;
	177	u8 buffer, alignbuffer;
	178	unsigned long absize;
	179
	180	absize = keylen + alignmask;
093900c2	181	buffer = kmalloc(absize, GFP_KERNEL);
004a403c LH	182	if (!buffer)
	183	return -ENOMEM;
	184
	185	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	186	memcpy(alignbuffer, key, keylen);
a70c5225	187	ret = tfm->setkey(tfm, alignbuffer, keylen);
8c32c516	188	kzfree(buffer);
004a403c LH	189	return ret;
	190	}
	191
66f6ce5e	192	int crypto_ahash_setkey(struct crypto_ahash tfm, const u8 key,
004a403c LH	193	unsigned int keylen)
004a403c LH	194	{
004a403c	195	unsigned long alignmask = crypto_ahash_alignmask(tfm);
9fa68f62	196	int err;
004a403c LH	197
004a403c LH	198	if ((unsigned long)key & alignmask)
9fa68f62 EB	199	err = ahash_setkey_unaligned(tfm, key, keylen);
	200	else
	201	err = tfm->setkey(tfm, key, keylen);
	202
	203	if (err)
	204	return err;
004a403c	205
9fa68f62 EB	206	crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
9fa68f62 EB	207	return 0;
004a403c	208	}
66f6ce5e	209	EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
004a403c	210
3751f402 HX	211	static int ahash_nosetkey(struct crypto_ahash tfm, const u8 key,
	212	unsigned int keylen)
	213	{
	214	return -ENOSYS;
	215	}
	216
66f6ce5e HX	217	static inline unsigned int ahash_align_buffer_size(unsigned len,
	218	unsigned long mask)
	219	{
	220	return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
	221	}
	222
1ffc9fbd	223	static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
66f6ce5e HX	224	{
	225	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	226	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	227	unsigned int ds = crypto_ahash_digestsize(tfm);
	228	struct ahash_request_priv *priv;
66f6ce5e HX	229
	230	priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
	231	(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
5befbd5a	232	GFP_KERNEL : GFP_ATOMIC);
66f6ce5e HX	233	if (!priv)
	234	return -ENOMEM;
	235
ab6bf4e5 MV	236	/*
	237	* WARNING: Voodoo programming below!
	238	*
	239	* The code below is obscure and hard to understand, thus explanation
	240	* is necessary. See include/crypto/hash.h and include/linux/crypto.h
	241	* to understand the layout of structures used here!
	242	*
	243	* The code here will replace portions of the ORIGINAL request with
	244	* pointers to new code and buffers so the hashing operation can store
	245	* the result in aligned buffer. We will call the modified request
	246	* an ADJUSTED request.
	247	*
	248	* The newly mangled request will look as such:
	249	*
	250	* req {
	251	* .result = ADJUSTED[new aligned buffer]
	252	* .base.complete = ADJUSTED[pointer to completion function]
	253	* .base.data = ADJUSTED[*req (pointer to self)]
	254	* .priv = ADJUSTED[new priv] {
	255	* .result = ORIGINAL(result)
	256	* .complete = ORIGINAL(base.complete)
	257	* .data = ORIGINAL(base.data)
	258	* }
	259	*/
	260
66f6ce5e HX	261	priv->result = req->result;
	262	priv->complete = req->base.complete;
	263	priv->data = req->base.data;
ef0579b6 HX	264	priv->flags = req->base.flags;
ef0579b6 HX	265
ab6bf4e5 MV	266	/*
	267	* WARNING: We do not backup req->priv here! The req->priv
	268	* is for internal use of the Crypto API and the
	269	* user must _NOT_ _EVER_ depend on it's content!
	270	*/
66f6ce5e HX	271
66f6ce5e HX	272	req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
1ffc9fbd	273	req->base.complete = cplt;
66f6ce5e HX	274	req->base.data = req;
	275	req->priv = priv;
	276
1ffc9fbd MV	277	return 0;
	278	}
	279
ef0579b6	280	static void ahash_restore_req(struct ahash_request *req, int err)
1ffc9fbd MV	281	{
	282	struct ahash_request_priv *priv = req->priv;
	283
ef0579b6 HX	284	if (!err)
	285	memcpy(priv->result, req->result,
	286	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	287
1ffc9fbd MV	288	/* Restore the original crypto request. */
1ffc9fbd MV	289	req->result = priv->result;
ef0579b6 HX	290
	291	ahash_request_set_callback(req, priv->flags,
	292	priv->complete, priv->data);
1ffc9fbd MV	293	req->priv = NULL;
	294
	295	/* Free the req->priv.priv from the ADJUSTED request. */
	296	kzfree(priv);
	297	}
	298
ef0579b6	299	static void ahash_notify_einprogress(struct ahash_request *req)
1ffc9fbd MV	300	{
1ffc9fbd MV	301	struct ahash_request_priv *priv = req->priv;
ef0579b6	302	struct crypto_async_request oreq;
1ffc9fbd	303
ef0579b6	304	oreq.data = priv->data;
1ffc9fbd	305
ef0579b6	306	priv->complete(&oreq, -EINPROGRESS);
1ffc9fbd MV	307	}
	308
	309	static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
	310	{
	311	struct ahash_request *areq = req->data;
	312
ef0579b6 HX	313	if (err == -EINPROGRESS) {
	314	ahash_notify_einprogress(areq);
	315	return;
	316	}
	317
1ffc9fbd MV	318	/*
	319	* Restore the original request, see ahash_op_unaligned() for what
	320	* goes where.
	321	*
	322	* The "struct ahash_request *req" here is in fact the "req.base"
	323	* from the ADJUSTED request from ahash_op_unaligned(), thus as it
	324	* is a pointer to self, it is also the ADJUSTED "req" .
	325	*/
	326
	327	/* First copy req->result into req->priv.result */
ef0579b6	328	ahash_restore_req(areq, err);
1ffc9fbd MV	329
	330	/* Complete the ORIGINAL request. */
	331	areq->base.complete(&areq->base, err);
	332	}
	333
	334	static int ahash_op_unaligned(struct ahash_request *req,
	335	int (op)(struct ahash_request ))
	336	{
	337	int err;
	338
	339	err = ahash_save_req(req, ahash_op_unaligned_done);
	340	if (err)
	341	return err;
	342
66f6ce5e	343	err = op(req);
4e5b0ad5	344	if (err == -EINPROGRESS \|\| err == -EBUSY)
ef0579b6 HX	345	return err;
	346
	347	ahash_restore_req(req, err);
66f6ce5e HX	348
	349	return err;
	350	}
	351
	352	static int crypto_ahash_op(struct ahash_request *req,
	353	int (op)(struct ahash_request ))
	354	{
	355	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	356	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	357
	358	if ((unsigned long)req->result & alignmask)
	359	return ahash_op_unaligned(req, op);
	360
	361	return op(req);
	362	}
	363
	364	int crypto_ahash_final(struct ahash_request *req)
	365	{
	366	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
	367	}
	368	EXPORT_SYMBOL_GPL(crypto_ahash_final);
	369
	370	int crypto_ahash_finup(struct ahash_request *req)
	371	{
	372	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
	373	}
	374	EXPORT_SYMBOL_GPL(crypto_ahash_finup);
	375
	376	int crypto_ahash_digest(struct ahash_request *req)
	377	{
9fa68f62 EB	378	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	379
	380	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
	381	return -ENOKEY;
	382
	383	return crypto_ahash_op(req, tfm->digest);
66f6ce5e HX	384	}
	385	EXPORT_SYMBOL_GPL(crypto_ahash_digest);
	386
ef0579b6	387	static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
66f6ce5e	388	{
ef0579b6	389	struct ahash_request *areq = req->data;
66f6ce5e HX	390
	391	if (err == -EINPROGRESS)
	392	return;
	393
ef0579b6	394	ahash_restore_req(areq, err);
66f6ce5e	395
d4a7a0fb	396	areq->base.complete(&areq->base, err);
66f6ce5e HX	397	}
	398
	399	static int ahash_def_finup_finish1(struct ahash_request *req, int err)
	400	{
	401	if (err)
	402	goto out;
	403
	404	req->base.complete = ahash_def_finup_done2;
ef0579b6	405
66f6ce5e	406	err = crypto_ahash_reqtfm(req)->final(req);
4e5b0ad5	407	if (err == -EINPROGRESS \|\| err == -EBUSY)
ef0579b6	408	return err;
66f6ce5e HX	409
66f6ce5e HX	410	out:
ef0579b6	411	ahash_restore_req(req, err);
66f6ce5e HX	412	return err;
	413	}
	414
	415	static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
	416	{
	417	struct ahash_request *areq = req->data;
66f6ce5e	418
ef0579b6 HX	419	if (err == -EINPROGRESS) {
	420	ahash_notify_einprogress(areq);
	421	return;
	422	}
	423
	424	areq->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	425
66f6ce5e	426	err = ahash_def_finup_finish1(areq, err);
ef0579b6 HX	427	if (areq->priv)
ef0579b6 HX	428	return;
66f6ce5e	429
d4a7a0fb	430	areq->base.complete(&areq->base, err);
66f6ce5e HX	431	}
	432
	433	static int ahash_def_finup(struct ahash_request *req)
	434	{
	435	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
d4a7a0fb	436	int err;
66f6ce5e	437
d4a7a0fb MV	438	err = ahash_save_req(req, ahash_def_finup_done1);
	439	if (err)
	440	return err;
66f6ce5e	441
d4a7a0fb	442	err = tfm->update(req);
4e5b0ad5	443	if (err == -EINPROGRESS \|\| err == -EBUSY)
ef0579b6 HX	444	return err;
ef0579b6 HX	445
d4a7a0fb	446	return ahash_def_finup_finish1(req, err);
66f6ce5e HX	447	}
	448
	449	static int ahash_no_export(struct ahash_request req, void out)
	450	{
	451	return -ENOSYS;
	452	}
	453
	454	static int ahash_no_import(struct ahash_request req, const void in)
	455	{
	456	return -ENOSYS;
	457	}
	458
88056ec3 HX	459	static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
	460	{
	461	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
	462	struct ahash_alg *alg = crypto_ahash_alg(hash);
88056ec3	463
66f6ce5e HX	464	hash->setkey = ahash_nosetkey;
	465	hash->export = ahash_no_export;
	466	hash->import = ahash_no_import;
	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;
66f6ce5e	476
a5596d63	477	if (alg->setkey) {
66f6ce5e	478	hash->setkey = alg->setkey;
9fa68f62 EB	479	if (!(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
9fa68f62 EB	480	crypto_ahash_set_flags(hash, CRYPTO_TFM_NEED_KEY);
a5596d63	481	}
66f6ce5e HX	482	if (alg->export)
	483	hash->export = alg->export;
	484	if (alg->import)
	485	hash->import = alg->import;
88056ec3 HX	486
	487	return 0;
	488	}
	489
	490	static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
	491	{
2495cf25 HX	492	if (alg->cra_type != &crypto_ahash_type)
2495cf25 HX	493	return sizeof(struct crypto_shash *);
88056ec3	494
2495cf25	495	return crypto_alg_extsize(alg);
88056ec3 HX	496	}
88056ec3 HX	497
3acc8473	498	#ifdef CONFIG_NET
6238cbae SK	499	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	500	{
	501	struct crypto_report_hash rhash;
	502
9a5467bf	503	strncpy(rhash.type, "ahash", sizeof(rhash.type));
6238cbae SK	504
	505	rhash.blocksize = alg->cra_blocksize;
	506	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
	507
6662df33 DM	508	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
	509	sizeof(struct crypto_report_hash), &rhash))
	510	goto nla_put_failure;
6238cbae SK	511	return 0;
	512
	513	nla_put_failure:
	514	return -EMSGSIZE;
	515	}
3acc8473 HX	516	#else
	517	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	518	{
	519	return -ENOSYS;
	520	}
	521	#endif
6238cbae	522
004a403c	523	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
d8c34b94	524	__maybe_unused;
004a403c LH	525	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	526	{
	527	seq_printf(m, "type : ahash\n");
	528	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
	529	"yes" : "no");
	530	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
88056ec3 HX	531	seq_printf(m, "digestsize : %u\n",
88056ec3 HX	532	__crypto_hash_alg_common(alg)->digestsize);
004a403c LH	533	}
	534
	535	const struct crypto_type crypto_ahash_type = {
88056ec3 HX	536	.extsize = crypto_ahash_extsize,
88056ec3 HX	537	.init_tfm = crypto_ahash_init_tfm,
004a403c LH	538	#ifdef CONFIG_PROC_FS
	539	.show = crypto_ahash_show,
	540	#endif
6238cbae	541	.report = crypto_ahash_report,
88056ec3 HX	542	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	543	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	544	.type = CRYPTO_ALG_TYPE_AHASH,
	545	.tfmsize = offsetof(struct crypto_ahash, base),
004a403c LH	546	};
	547	EXPORT_SYMBOL_GPL(crypto_ahash_type);
	548
88056ec3 HX	549	struct crypto_ahash crypto_alloc_ahash(const char alg_name, u32 type,
	550	u32 mask)
	551	{
	552	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
	553	}
	554	EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
	555
8d18e34c HX	556	int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
	557	{
	558	return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
	559	}
	560	EXPORT_SYMBOL_GPL(crypto_has_ahash);
	561
01c2dece HX	562	static int ahash_prepare_alg(struct ahash_alg *alg)
	563	{
	564	struct crypto_alg *base = &alg->halg.base;
	565
	566	if (alg->halg.digestsize > PAGE_SIZE / 8 \|\|
8996eafd RK	567	alg->halg.statesize > PAGE_SIZE / 8 \|\|
8996eafd RK	568	alg->halg.statesize == 0)
01c2dece HX	569	return -EINVAL;
	570
	571	base->cra_type = &crypto_ahash_type;
	572	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	573	base->cra_flags \|= CRYPTO_ALG_TYPE_AHASH;
	574
	575	return 0;
	576	}
	577
	578	int crypto_register_ahash(struct ahash_alg *alg)
	579	{
	580	struct crypto_alg *base = &alg->halg.base;
	581	int err;
	582
	583	err = ahash_prepare_alg(alg);
	584	if (err)
	585	return err;
	586
	587	return crypto_register_alg(base);
	588	}
	589	EXPORT_SYMBOL_GPL(crypto_register_ahash);
	590
	591	int crypto_unregister_ahash(struct ahash_alg *alg)
	592	{
	593	return crypto_unregister_alg(&alg->halg.base);
	594	}
	595	EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
	596
6f7473c5 RV	597	int crypto_register_ahashes(struct ahash_alg *algs, int count)
	598	{
	599	int i, ret;
	600
	601	for (i = 0; i < count; i++) {
	602	ret = crypto_register_ahash(&algs[i]);
	603	if (ret)
	604	goto err;
	605	}
	606
	607	return 0;
	608
	609	err:
	610	for (--i; i >= 0; --i)
	611	crypto_unregister_ahash(&algs[i]);
	612
	613	return ret;
	614	}
	615	EXPORT_SYMBOL_GPL(crypto_register_ahashes);
	616
	617	void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
	618	{
	619	int i;
	620
	621	for (i = count - 1; i >= 0; --i)
	622	crypto_unregister_ahash(&algs[i]);
	623	}
	624	EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);
	625
01c2dece HX	626	int ahash_register_instance(struct crypto_template *tmpl,
	627	struct ahash_instance *inst)
	628	{
	629	int err;
	630
	631	err = ahash_prepare_alg(&inst->alg);
	632	if (err)
	633	return err;
	634
	635	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
	636	}
	637	EXPORT_SYMBOL_GPL(ahash_register_instance);
	638
	639	void ahash_free_instance(struct crypto_instance *inst)
	640	{
	641	crypto_drop_spawn(crypto_instance_ctx(inst));
	642	kfree(ahash_instance(inst));
	643	}
	644	EXPORT_SYMBOL_GPL(ahash_free_instance);
	645
	646	int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
	647	struct hash_alg_common *alg,
	648	struct crypto_instance *inst)
	649	{
	650	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
	651	&crypto_ahash_type);
	652	}
	653	EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
	654
	655	struct hash_alg_common ahash_attr_alg(struct rtattr rta, u32 type, u32 mask)
	656	{
	657	struct crypto_alg *alg;
	658
	659	alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
	660	return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
	661	}
	662	EXPORT_SYMBOL_GPL(ahash_attr_alg);
	663
cd6ed77a EB	664	bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
	665	{
	666	struct crypto_alg *alg = &halg->base;
	667
	668	if (alg->cra_type != &crypto_ahash_type)
	669	return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));
	670
	671	return __crypto_ahash_alg(alg)->setkey != NULL;
	672	}
	673	EXPORT_SYMBOL_GPL(crypto_hash_alg_has_setkey);
	674
004a403c LH	675	MODULE_LICENSE("GPL");
004a403c LH	676	MODULE_DESCRIPTION("Asynchronous cryptographic hash type");