[mirror_ubuntu-bionic-kernel.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->pg = sg_page(sg);
	walk->offset = sg->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);

int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
				  struct crypto_hash_walk *walk,
				  struct scatterlist *sg, unsigned int len)
{
	walk->total = len;

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

	walk->alignmask = crypto_hash_alignmask(hdesc->tfm);
	walk->sg = sg;
	walk->flags = hdesc->flags & CRYPTO_TFM_REQ_MASK;

	return hash_walk_new_entry(walk);
}

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->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->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);

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;
	72	walk->pg = sg_page(sg);
	73	walk->offset = sg->offset;
	74	walk->entrylen = sg->length;
	75
	76	if (walk->entrylen > walk->total)
	77	walk->entrylen = walk->total;
	78	walk->total -= walk->entrylen;
	79
	80	return hash_walk_next(walk);
	81	}
	82
	83	int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
	84	{
	85	unsigned int alignmask = walk->alignmask;
	86	unsigned int nbytes = walk->entrylen;
	87
	88	walk->data -= walk->offset;
	89
	90	if (nbytes && walk->offset & alignmask && !err) {
20036252 HX	91	walk->offset = ALIGN(walk->offset, alignmask + 1);
	92	walk->data += walk->offset;
	93
	94	nbytes = min(nbytes,
	95	((unsigned int)(PAGE_SIZE)) - walk->offset);
	96	walk->entrylen -= nbytes;
	97
	98	return nbytes;
	99	}
	100
75ecb231 HX	101	if (walk->flags & CRYPTO_ALG_ASYNC)
	102	kunmap(walk->pg);
	103	else {
	104	kunmap_atomic(walk->data);
	105	/*
	106	* The may sleep test only makes sense for sync users.
	107	* Async users don't need to sleep here anyway.
	108	*/
	109	crypto_yield(walk->flags);
	110	}
20036252 HX	111
	112	if (err)
	113	return err;
	114
d315a0e0 HX	115	if (nbytes) {
	116	walk->offset = 0;
	117	walk->pg++;
20036252	118	return hash_walk_next(walk);
d315a0e0	119	}
20036252 HX	120
	121	if (!walk->total)
	122	return 0;
	123
5be4d4c9	124	walk->sg = sg_next(walk->sg);
20036252 HX	125
	126	return hash_walk_new_entry(walk);
	127	}
	128	EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
	129
	130	int crypto_hash_walk_first(struct ahash_request *req,
	131	struct crypto_hash_walk *walk)
	132	{
	133	walk->total = req->nbytes;
	134
6d9529c5 TC	135	if (!walk->total) {
6d9529c5 TC	136	walk->entrylen = 0;
20036252	137	return 0;
6d9529c5	138	}
20036252 HX	139
	140	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	141	walk->sg = req->src;
75ecb231	142	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
20036252 HX	143
	144	return hash_walk_new_entry(walk);
	145	}
	146	EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
	147
75ecb231 HX	148	int crypto_ahash_walk_first(struct ahash_request *req,
	149	struct crypto_hash_walk *walk)
	150	{
	151	walk->total = req->nbytes;
	152
6d9529c5 TC	153	if (!walk->total) {
6d9529c5 TC	154	walk->entrylen = 0;
75ecb231	155	return 0;
6d9529c5	156	}
75ecb231 HX	157
	158	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	159	walk->sg = req->src;
	160	walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
	161	walk->flags \|= CRYPTO_ALG_ASYNC;
	162
	163	BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
	164
	165	return hash_walk_new_entry(walk);
	166	}
	167	EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
	168
5f7082ed HX	169	int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
	170	struct crypto_hash_walk *walk,
	171	struct scatterlist *sg, unsigned int len)
	172	{
	173	walk->total = len;
	174
6d9529c5 TC	175	if (!walk->total) {
6d9529c5 TC	176	walk->entrylen = 0;
5f7082ed	177	return 0;
6d9529c5	178	}
5f7082ed HX	179
	180	walk->alignmask = crypto_hash_alignmask(hdesc->tfm);
	181	walk->sg = sg;
75ecb231	182	walk->flags = hdesc->flags & CRYPTO_TFM_REQ_MASK;
5f7082ed HX	183
	184	return hash_walk_new_entry(walk);
	185	}
	186
004a403c LH	187	static int ahash_setkey_unaligned(struct crypto_ahash tfm, const u8 key,
	188	unsigned int keylen)
	189	{
004a403c LH	190	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	191	int ret;
	192	u8 buffer, alignbuffer;
	193	unsigned long absize;
	194
	195	absize = keylen + alignmask;
093900c2	196	buffer = kmalloc(absize, GFP_KERNEL);
004a403c LH	197	if (!buffer)
	198	return -ENOMEM;
	199
	200	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	201	memcpy(alignbuffer, key, keylen);
a70c5225	202	ret = tfm->setkey(tfm, alignbuffer, keylen);
8c32c516	203	kzfree(buffer);
004a403c LH	204	return ret;
	205	}
	206
66f6ce5e	207	int crypto_ahash_setkey(struct crypto_ahash tfm, const u8 key,
004a403c LH	208	unsigned int keylen)
004a403c LH	209	{
004a403c LH	210	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	211
	212	if ((unsigned long)key & alignmask)
	213	return ahash_setkey_unaligned(tfm, key, keylen);
	214
a70c5225	215	return tfm->setkey(tfm, key, keylen);
004a403c	216	}
66f6ce5e	217	EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
004a403c	218
3751f402 HX	219	static int ahash_nosetkey(struct crypto_ahash tfm, const u8 key,
	220	unsigned int keylen)
	221	{
	222	return -ENOSYS;
	223	}
	224
66f6ce5e HX	225	static inline unsigned int ahash_align_buffer_size(unsigned len,
	226	unsigned long mask)
	227	{
	228	return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
	229	}
	230
1ffc9fbd	231	static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
66f6ce5e HX	232	{
	233	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	234	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	235	unsigned int ds = crypto_ahash_digestsize(tfm);
	236	struct ahash_request_priv *priv;
66f6ce5e HX	237
	238	priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
	239	(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
5befbd5a	240	GFP_KERNEL : GFP_ATOMIC);
66f6ce5e HX	241	if (!priv)
	242	return -ENOMEM;
	243
ab6bf4e5 MV	244	/*
	245	* WARNING: Voodoo programming below!
	246	*
	247	* The code below is obscure and hard to understand, thus explanation
	248	* is necessary. See include/crypto/hash.h and include/linux/crypto.h
	249	* to understand the layout of structures used here!
	250	*
	251	* The code here will replace portions of the ORIGINAL request with
	252	* pointers to new code and buffers so the hashing operation can store
	253	* the result in aligned buffer. We will call the modified request
	254	* an ADJUSTED request.
	255	*
	256	* The newly mangled request will look as such:
	257	*
	258	* req {
	259	* .result = ADJUSTED[new aligned buffer]
	260	* .base.complete = ADJUSTED[pointer to completion function]
	261	* .base.data = ADJUSTED[*req (pointer to self)]
	262	* .priv = ADJUSTED[new priv] {
	263	* .result = ORIGINAL(result)
	264	* .complete = ORIGINAL(base.complete)
	265	* .data = ORIGINAL(base.data)
	266	* }
	267	*/
	268
66f6ce5e HX	269	priv->result = req->result;
	270	priv->complete = req->base.complete;
	271	priv->data = req->base.data;
ab6bf4e5 MV	272	/*
	273	* WARNING: We do not backup req->priv here! The req->priv
	274	* is for internal use of the Crypto API and the
	275	* user must _NOT_ _EVER_ depend on it's content!
	276	*/
66f6ce5e HX	277
66f6ce5e HX	278	req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
1ffc9fbd	279	req->base.complete = cplt;
66f6ce5e HX	280	req->base.data = req;
	281	req->priv = priv;
	282
1ffc9fbd MV	283	return 0;
	284	}
	285
	286	static void ahash_restore_req(struct ahash_request *req)
	287	{
	288	struct ahash_request_priv *priv = req->priv;
	289
	290	/* Restore the original crypto request. */
	291	req->result = priv->result;
	292	req->base.complete = priv->complete;
	293	req->base.data = priv->data;
	294	req->priv = NULL;
	295
	296	/* Free the req->priv.priv from the ADJUSTED request. */
	297	kzfree(priv);
	298	}
	299
	300	static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
	301	{
	302	struct ahash_request_priv *priv = req->priv;
	303
	304	if (err == -EINPROGRESS)
	305	return;
	306
	307	if (!err)
	308	memcpy(priv->result, req->result,
	309	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	310
	311	ahash_restore_req(req);
	312	}
	313
	314	static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
	315	{
	316	struct ahash_request *areq = req->data;
	317
	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 */
	328	ahash_op_unaligned_finish(areq, err);
	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 HX	343	err = op(req);
	344	ahash_op_unaligned_finish(req, err);
	345
	346	return err;
	347	}
	348
	349	static int crypto_ahash_op(struct ahash_request *req,
	350	int (op)(struct ahash_request ))
	351	{
	352	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	353	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	354
	355	if ((unsigned long)req->result & alignmask)
	356	return ahash_op_unaligned(req, op);
	357
	358	return op(req);
	359	}
	360
	361	int crypto_ahash_final(struct ahash_request *req)
	362	{
	363	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
	364	}
	365	EXPORT_SYMBOL_GPL(crypto_ahash_final);
	366
	367	int crypto_ahash_finup(struct ahash_request *req)
	368	{
	369	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
	370	}
	371	EXPORT_SYMBOL_GPL(crypto_ahash_finup);
	372
	373	int crypto_ahash_digest(struct ahash_request *req)
	374	{
	375	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
	376	}
	377	EXPORT_SYMBOL_GPL(crypto_ahash_digest);
	378
	379	static void ahash_def_finup_finish2(struct ahash_request *req, int err)
	380	{
	381	struct ahash_request_priv *priv = req->priv;
	382
	383	if (err == -EINPROGRESS)
	384	return;
	385
	386	if (!err)
	387	memcpy(priv->result, req->result,
	388	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	389
d4a7a0fb	390	ahash_restore_req(req);
66f6ce5e HX	391	}
	392
	393	static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
	394	{
	395	struct ahash_request *areq = req->data;
66f6ce5e HX	396
	397	ahash_def_finup_finish2(areq, err);
	398
d4a7a0fb	399	areq->base.complete(&areq->base, err);
66f6ce5e HX	400	}
	401
	402	static int ahash_def_finup_finish1(struct ahash_request *req, int err)
	403	{
	404	if (err)
	405	goto out;
	406
	407	req->base.complete = ahash_def_finup_done2;
	408	req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	409	err = crypto_ahash_reqtfm(req)->final(req);
	410
	411	out:
	412	ahash_def_finup_finish2(req, err);
	413	return err;
	414	}
	415
	416	static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
	417	{
	418	struct ahash_request *areq = req->data;
66f6ce5e HX	419
	420	err = ahash_def_finup_finish1(areq, err);
	421
d4a7a0fb	422	areq->base.complete(&areq->base, err);
66f6ce5e HX	423	}
	424
	425	static int ahash_def_finup(struct ahash_request *req)
	426	{
	427	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
d4a7a0fb	428	int err;
66f6ce5e	429
d4a7a0fb MV	430	err = ahash_save_req(req, ahash_def_finup_done1);
	431	if (err)
	432	return err;
66f6ce5e	433
d4a7a0fb MV	434	err = tfm->update(req);
d4a7a0fb MV	435	return ahash_def_finup_finish1(req, err);
66f6ce5e HX	436	}
	437
	438	static int ahash_no_export(struct ahash_request req, void out)
	439	{
	440	return -ENOSYS;
	441	}
	442
	443	static int ahash_no_import(struct ahash_request req, const void in)
	444	{
	445	return -ENOSYS;
	446	}
	447
88056ec3 HX	448	static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
	449	{
	450	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
	451	struct ahash_alg *alg = crypto_ahash_alg(hash);
88056ec3	452
66f6ce5e HX	453	hash->setkey = ahash_nosetkey;
	454	hash->export = ahash_no_export;
	455	hash->import = ahash_no_import;
	456
88056ec3 HX	457	if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
	458	return crypto_init_shash_ops_async(tfm);
	459
88056ec3 HX	460	hash->init = alg->init;
88056ec3 HX	461	hash->update = alg->update;
66f6ce5e HX	462	hash->final = alg->final;
66f6ce5e HX	463	hash->finup = alg->finup ?: ahash_def_finup;
88056ec3	464	hash->digest = alg->digest;
66f6ce5e HX	465
	466	if (alg->setkey)
	467	hash->setkey = alg->setkey;
	468	if (alg->export)
	469	hash->export = alg->export;
	470	if (alg->import)
	471	hash->import = alg->import;
88056ec3 HX	472
	473	return 0;
	474	}
	475
	476	static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
	477	{
	478	if (alg->cra_type == &crypto_ahash_type)
	479	return alg->cra_ctxsize;
	480
	481	return sizeof(struct crypto_shash *);
	482	}
	483
3acc8473	484	#ifdef CONFIG_NET
6238cbae SK	485	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	486	{
	487	struct crypto_report_hash rhash;
	488
9a5467bf	489	strncpy(rhash.type, "ahash", sizeof(rhash.type));
6238cbae SK	490
	491	rhash.blocksize = alg->cra_blocksize;
	492	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
	493
6662df33 DM	494	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
	495	sizeof(struct crypto_report_hash), &rhash))
	496	goto nla_put_failure;
6238cbae SK	497	return 0;
	498
	499	nla_put_failure:
	500	return -EMSGSIZE;
	501	}
3acc8473 HX	502	#else
	503	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	504	{
	505	return -ENOSYS;
	506	}
	507	#endif
6238cbae	508
004a403c LH	509	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	510	__attribute__ ((unused));
	511	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	512	{
	513	seq_printf(m, "type : ahash\n");
	514	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
	515	"yes" : "no");
	516	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
88056ec3 HX	517	seq_printf(m, "digestsize : %u\n",
88056ec3 HX	518	__crypto_hash_alg_common(alg)->digestsize);
004a403c LH	519	}
	520
	521	const struct crypto_type crypto_ahash_type = {
88056ec3 HX	522	.extsize = crypto_ahash_extsize,
88056ec3 HX	523	.init_tfm = crypto_ahash_init_tfm,
004a403c LH	524	#ifdef CONFIG_PROC_FS
	525	.show = crypto_ahash_show,
	526	#endif
6238cbae	527	.report = crypto_ahash_report,
88056ec3 HX	528	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	529	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	530	.type = CRYPTO_ALG_TYPE_AHASH,
	531	.tfmsize = offsetof(struct crypto_ahash, base),
004a403c LH	532	};
	533	EXPORT_SYMBOL_GPL(crypto_ahash_type);
	534
88056ec3 HX	535	struct crypto_ahash crypto_alloc_ahash(const char alg_name, u32 type,
	536	u32 mask)
	537	{
	538	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
	539	}
	540	EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
	541
01c2dece HX	542	static int ahash_prepare_alg(struct ahash_alg *alg)
	543	{
	544	struct crypto_alg *base = &alg->halg.base;
	545
	546	if (alg->halg.digestsize > PAGE_SIZE / 8 \|\|
8996eafd RK	547	alg->halg.statesize > PAGE_SIZE / 8 \|\|
8996eafd RK	548	alg->halg.statesize == 0)
01c2dece HX	549	return -EINVAL;
	550
	551	base->cra_type = &crypto_ahash_type;
	552	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	553	base->cra_flags \|= CRYPTO_ALG_TYPE_AHASH;
	554
	555	return 0;
	556	}
	557
	558	int crypto_register_ahash(struct ahash_alg *alg)
	559	{
	560	struct crypto_alg *base = &alg->halg.base;
	561	int err;
	562
	563	err = ahash_prepare_alg(alg);
	564	if (err)
	565	return err;
	566
	567	return crypto_register_alg(base);
	568	}
	569	EXPORT_SYMBOL_GPL(crypto_register_ahash);
	570
	571	int crypto_unregister_ahash(struct ahash_alg *alg)
	572	{
	573	return crypto_unregister_alg(&alg->halg.base);
	574	}
	575	EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
	576
	577	int ahash_register_instance(struct crypto_template *tmpl,
	578	struct ahash_instance *inst)
	579	{
	580	int err;
	581
	582	err = ahash_prepare_alg(&inst->alg);
	583	if (err)
	584	return err;
	585
	586	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
	587	}
	588	EXPORT_SYMBOL_GPL(ahash_register_instance);
	589
	590	void ahash_free_instance(struct crypto_instance *inst)
	591	{
	592	crypto_drop_spawn(crypto_instance_ctx(inst));
	593	kfree(ahash_instance(inst));
	594	}
	595	EXPORT_SYMBOL_GPL(ahash_free_instance);
	596
	597	int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
	598	struct hash_alg_common *alg,
	599	struct crypto_instance *inst)
	600	{
	601	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
	602	&crypto_ahash_type);
	603	}
	604	EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
	605
	606	struct hash_alg_common ahash_attr_alg(struct rtattr rta, u32 type, u32 mask)
	607	{
	608	struct crypto_alg *alg;
	609
	610	alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
	611	return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
	612	}
613	EXPORT_SYMBOL_GPL(ahash_attr_alg);
614
004a403c LH	615	MODULE_LICENSE("GPL");
004a403c LH	616	MODULE_DESCRIPTION("Asynchronous cryptographic hash type");