[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/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);

	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;
	}

	kunmap_atomic(walk->data);
	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 = scatterwalk_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)
		return 0;

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

	return hash_walk_new_entry(walk);
}
EXPORT_SYMBOL_GPL(crypto_hash_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)
		return 0;

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

	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)
		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>
004a403c LH	18	#include <linux/err.h>
	19	#include <linux/kernel.h>
	20	#include <linux/module.h>
	21	#include <linux/sched.h>
	22	#include <linux/slab.h>
	23	#include <linux/seq_file.h>
6238cbae SK	24	#include <linux/cryptouser.h>
6238cbae SK	25	#include <net/netlink.h>
004a403c LH	26
	27	#include "internal.h"
	28
66f6ce5e HX	29	struct ahash_request_priv {
	30	crypto_completion_t complete;
	31	void *data;
	32	u8 *result;
	33	void *ubuf[] CRYPTO_MINALIGN_ATTR;
	34	};
	35
88056ec3 HX	36	static inline struct ahash_alg crypto_ahash_alg(struct crypto_ahash hash)
	37	{
	38	return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
	39	halg);
	40	}
	41
20036252 HX	42	static int hash_walk_next(struct crypto_hash_walk *walk)
	43	{
	44	unsigned int alignmask = walk->alignmask;
	45	unsigned int offset = walk->offset;
	46	unsigned int nbytes = min(walk->entrylen,
	47	((unsigned int)(PAGE_SIZE)) - offset);
	48
f0dfc0b0	49	walk->data = kmap_atomic(walk->pg);
20036252 HX	50	walk->data += offset;
20036252 HX	51
23a75eee SÖ	52	if (offset & alignmask) {
	53	unsigned int unaligned = alignmask + 1 - (offset & alignmask);
	54	if (nbytes > unaligned)
	55	nbytes = unaligned;
	56	}
20036252 HX	57
	58	walk->entrylen -= nbytes;
	59	return nbytes;
	60	}
	61
	62	static int hash_walk_new_entry(struct crypto_hash_walk *walk)
	63	{
	64	struct scatterlist *sg;
	65
	66	sg = walk->sg;
	67	walk->pg = sg_page(sg);
	68	walk->offset = sg->offset;
	69	walk->entrylen = sg->length;
	70
	71	if (walk->entrylen > walk->total)
	72	walk->entrylen = walk->total;
	73	walk->total -= walk->entrylen;
	74
	75	return hash_walk_next(walk);
	76	}
	77
	78	int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
	79	{
	80	unsigned int alignmask = walk->alignmask;
	81	unsigned int nbytes = walk->entrylen;
	82
	83	walk->data -= walk->offset;
	84
	85	if (nbytes && walk->offset & alignmask && !err) {
20036252 HX	86	walk->offset = ALIGN(walk->offset, alignmask + 1);
	87	walk->data += walk->offset;
	88
	89	nbytes = min(nbytes,
	90	((unsigned int)(PAGE_SIZE)) - walk->offset);
	91	walk->entrylen -= nbytes;
	92
	93	return nbytes;
	94	}
	95
f0dfc0b0	96	kunmap_atomic(walk->data);
20036252 HX	97	crypto_yield(walk->flags);
	98
	99	if (err)
	100	return err;
	101
d315a0e0 HX	102	if (nbytes) {
	103	walk->offset = 0;
	104	walk->pg++;
20036252	105	return hash_walk_next(walk);
d315a0e0	106	}
20036252 HX	107
	108	if (!walk->total)
	109	return 0;
	110
	111	walk->sg = scatterwalk_sg_next(walk->sg);
	112
	113	return hash_walk_new_entry(walk);
	114	}
	115	EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
	116
	117	int crypto_hash_walk_first(struct ahash_request *req,
	118	struct crypto_hash_walk *walk)
	119	{
	120	walk->total = req->nbytes;
	121
	122	if (!walk->total)
	123	return 0;
	124
	125	walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
	126	walk->sg = req->src;
	127	walk->flags = req->base.flags;
	128
	129	return hash_walk_new_entry(walk);
	130	}
	131	EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
	132
5f7082ed HX	133	int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
	134	struct crypto_hash_walk *walk,
	135	struct scatterlist *sg, unsigned int len)
	136	{
	137	walk->total = len;
	138
	139	if (!walk->total)
	140	return 0;
	141
	142	walk->alignmask = crypto_hash_alignmask(hdesc->tfm);
	143	walk->sg = sg;
	144	walk->flags = hdesc->flags;
	145
	146	return hash_walk_new_entry(walk);
	147	}
	148
004a403c LH	149	static int ahash_setkey_unaligned(struct crypto_ahash tfm, const u8 key,
	150	unsigned int keylen)
	151	{
004a403c LH	152	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	153	int ret;
	154	u8 buffer, alignbuffer;
	155	unsigned long absize;
	156
	157	absize = keylen + alignmask;
093900c2	158	buffer = kmalloc(absize, GFP_KERNEL);
004a403c LH	159	if (!buffer)
	160	return -ENOMEM;
	161
	162	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	163	memcpy(alignbuffer, key, keylen);
a70c5225	164	ret = tfm->setkey(tfm, alignbuffer, keylen);
8c32c516	165	kzfree(buffer);
004a403c LH	166	return ret;
	167	}
	168
66f6ce5e	169	int crypto_ahash_setkey(struct crypto_ahash tfm, const u8 key,
004a403c LH	170	unsigned int keylen)
004a403c LH	171	{
004a403c LH	172	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	173
	174	if ((unsigned long)key & alignmask)
	175	return ahash_setkey_unaligned(tfm, key, keylen);
	176
a70c5225	177	return tfm->setkey(tfm, key, keylen);
004a403c	178	}
66f6ce5e	179	EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
004a403c	180
3751f402 HX	181	static int ahash_nosetkey(struct crypto_ahash tfm, const u8 key,
	182	unsigned int keylen)
	183	{
	184	return -ENOSYS;
	185	}
	186
66f6ce5e HX	187	static inline unsigned int ahash_align_buffer_size(unsigned len,
	188	unsigned long mask)
	189	{
	190	return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
	191	}
	192
1ffc9fbd	193	static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
66f6ce5e HX	194	{
	195	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	196	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	197	unsigned int ds = crypto_ahash_digestsize(tfm);
	198	struct ahash_request_priv *priv;
66f6ce5e HX	199
	200	priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
	201	(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
5befbd5a	202	GFP_KERNEL : GFP_ATOMIC);
66f6ce5e HX	203	if (!priv)
	204	return -ENOMEM;
	205
ab6bf4e5 MV	206	/*
	207	* WARNING: Voodoo programming below!
	208	*
	209	* The code below is obscure and hard to understand, thus explanation
	210	* is necessary. See include/crypto/hash.h and include/linux/crypto.h
	211	* to understand the layout of structures used here!
	212	*
	213	* The code here will replace portions of the ORIGINAL request with
	214	* pointers to new code and buffers so the hashing operation can store
	215	* the result in aligned buffer. We will call the modified request
	216	* an ADJUSTED request.
	217	*
	218	* The newly mangled request will look as such:
	219	*
	220	* req {
	221	* .result = ADJUSTED[new aligned buffer]
	222	* .base.complete = ADJUSTED[pointer to completion function]
	223	* .base.data = ADJUSTED[*req (pointer to self)]
	224	* .priv = ADJUSTED[new priv] {
	225	* .result = ORIGINAL(result)
	226	* .complete = ORIGINAL(base.complete)
	227	* .data = ORIGINAL(base.data)
	228	* }
	229	*/
	230
66f6ce5e HX	231	priv->result = req->result;
	232	priv->complete = req->base.complete;
	233	priv->data = req->base.data;
ab6bf4e5 MV	234	/*
	235	* WARNING: We do not backup req->priv here! The req->priv
	236	* is for internal use of the Crypto API and the
	237	* user must _NOT_ _EVER_ depend on it's content!
	238	*/
66f6ce5e HX	239
66f6ce5e HX	240	req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
1ffc9fbd	241	req->base.complete = cplt;
66f6ce5e HX	242	req->base.data = req;
	243	req->priv = priv;
	244
1ffc9fbd MV	245	return 0;
	246	}
	247
	248	static void ahash_restore_req(struct ahash_request *req)
	249	{
	250	struct ahash_request_priv *priv = req->priv;
	251
	252	/* Restore the original crypto request. */
	253	req->result = priv->result;
	254	req->base.complete = priv->complete;
	255	req->base.data = priv->data;
	256	req->priv = NULL;
	257
	258	/* Free the req->priv.priv from the ADJUSTED request. */
	259	kzfree(priv);
	260	}
	261
	262	static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
	263	{
	264	struct ahash_request_priv *priv = req->priv;
	265
	266	if (err == -EINPROGRESS)
	267	return;
	268
	269	if (!err)
	270	memcpy(priv->result, req->result,
	271	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	272
	273	ahash_restore_req(req);
	274	}
	275
	276	static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
	277	{
	278	struct ahash_request *areq = req->data;
	279
	280	/*
	281	* Restore the original request, see ahash_op_unaligned() for what
	282	* goes where.
	283	*
	284	* The "struct ahash_request *req" here is in fact the "req.base"
	285	* from the ADJUSTED request from ahash_op_unaligned(), thus as it
	286	* is a pointer to self, it is also the ADJUSTED "req" .
	287	*/
	288
	289	/* First copy req->result into req->priv.result */
	290	ahash_op_unaligned_finish(areq, err);
	291
	292	/* Complete the ORIGINAL request. */
	293	areq->base.complete(&areq->base, err);
	294	}
	295
	296	static int ahash_op_unaligned(struct ahash_request *req,
	297	int (op)(struct ahash_request ))
	298	{
	299	int err;
	300
	301	err = ahash_save_req(req, ahash_op_unaligned_done);
	302	if (err)
	303	return err;
	304
66f6ce5e HX	305	err = op(req);
	306	ahash_op_unaligned_finish(req, err);
	307
	308	return err;
	309	}
	310
	311	static int crypto_ahash_op(struct ahash_request *req,
	312	int (op)(struct ahash_request ))
	313	{
	314	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	315	unsigned long alignmask = crypto_ahash_alignmask(tfm);
	316
	317	if ((unsigned long)req->result & alignmask)
	318	return ahash_op_unaligned(req, op);
	319
	320	return op(req);
	321	}
	322
	323	int crypto_ahash_final(struct ahash_request *req)
	324	{
	325	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
	326	}
	327	EXPORT_SYMBOL_GPL(crypto_ahash_final);
	328
	329	int crypto_ahash_finup(struct ahash_request *req)
	330	{
	331	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
	332	}
	333	EXPORT_SYMBOL_GPL(crypto_ahash_finup);
	334
	335	int crypto_ahash_digest(struct ahash_request *req)
	336	{
	337	return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
	338	}
	339	EXPORT_SYMBOL_GPL(crypto_ahash_digest);
	340
	341	static void ahash_def_finup_finish2(struct ahash_request *req, int err)
	342	{
	343	struct ahash_request_priv *priv = req->priv;
	344
	345	if (err == -EINPROGRESS)
	346	return;
	347
	348	if (!err)
	349	memcpy(priv->result, req->result,
	350	crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
	351
d4a7a0fb	352	ahash_restore_req(req);
66f6ce5e HX	353	}
	354
	355	static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
	356	{
	357	struct ahash_request *areq = req->data;
66f6ce5e HX	358
	359	ahash_def_finup_finish2(areq, err);
	360
d4a7a0fb	361	areq->base.complete(&areq->base, err);
66f6ce5e HX	362	}
	363
	364	static int ahash_def_finup_finish1(struct ahash_request *req, int err)
	365	{
	366	if (err)
	367	goto out;
	368
	369	req->base.complete = ahash_def_finup_done2;
	370	req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	371	err = crypto_ahash_reqtfm(req)->final(req);
	372
	373	out:
	374	ahash_def_finup_finish2(req, err);
	375	return err;
	376	}
	377
	378	static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
	379	{
	380	struct ahash_request *areq = req->data;
66f6ce5e HX	381
	382	err = ahash_def_finup_finish1(areq, err);
	383
d4a7a0fb	384	areq->base.complete(&areq->base, err);
66f6ce5e HX	385	}
	386
	387	static int ahash_def_finup(struct ahash_request *req)
	388	{
	389	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
d4a7a0fb	390	int err;
66f6ce5e	391
d4a7a0fb MV	392	err = ahash_save_req(req, ahash_def_finup_done1);
	393	if (err)
	394	return err;
66f6ce5e	395
d4a7a0fb MV	396	err = tfm->update(req);
d4a7a0fb MV	397	return ahash_def_finup_finish1(req, err);
66f6ce5e HX	398	}
	399
	400	static int ahash_no_export(struct ahash_request req, void out)
	401	{
	402	return -ENOSYS;
	403	}
	404
	405	static int ahash_no_import(struct ahash_request req, const void in)
	406	{
	407	return -ENOSYS;
	408	}
	409
88056ec3 HX	410	static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
	411	{
	412	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
	413	struct ahash_alg *alg = crypto_ahash_alg(hash);
88056ec3	414
66f6ce5e HX	415	hash->setkey = ahash_nosetkey;
	416	hash->export = ahash_no_export;
	417	hash->import = ahash_no_import;
	418
88056ec3 HX	419	if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
	420	return crypto_init_shash_ops_async(tfm);
	421
88056ec3 HX	422	hash->init = alg->init;
88056ec3 HX	423	hash->update = alg->update;
66f6ce5e HX	424	hash->final = alg->final;
66f6ce5e HX	425	hash->finup = alg->finup ?: ahash_def_finup;
88056ec3	426	hash->digest = alg->digest;
66f6ce5e HX	427
	428	if (alg->setkey)
	429	hash->setkey = alg->setkey;
	430	if (alg->export)
	431	hash->export = alg->export;
	432	if (alg->import)
	433	hash->import = alg->import;
88056ec3 HX	434
	435	return 0;
	436	}
	437
	438	static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
	439	{
	440	if (alg->cra_type == &crypto_ahash_type)
	441	return alg->cra_ctxsize;
	442
	443	return sizeof(struct crypto_shash *);
	444	}
	445
3acc8473	446	#ifdef CONFIG_NET
6238cbae SK	447	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	448	{
	449	struct crypto_report_hash rhash;
	450
9a5467bf	451	strncpy(rhash.type, "ahash", sizeof(rhash.type));
6238cbae SK	452
	453	rhash.blocksize = alg->cra_blocksize;
	454	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
	455
6662df33 DM	456	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
	457	sizeof(struct crypto_report_hash), &rhash))
	458	goto nla_put_failure;
6238cbae SK	459	return 0;
	460
	461	nla_put_failure:
	462	return -EMSGSIZE;
	463	}
3acc8473 HX	464	#else
	465	static int crypto_ahash_report(struct sk_buff skb, struct crypto_alg alg)
	466	{
	467	return -ENOSYS;
	468	}
	469	#endif
6238cbae	470
004a403c LH	471	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	472	__attribute__ ((unused));
	473	static void crypto_ahash_show(struct seq_file m, struct crypto_alg alg)
	474	{
	475	seq_printf(m, "type : ahash\n");
	476	seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
	477	"yes" : "no");
	478	seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
88056ec3 HX	479	seq_printf(m, "digestsize : %u\n",
88056ec3 HX	480	__crypto_hash_alg_common(alg)->digestsize);
004a403c LH	481	}
	482
	483	const struct crypto_type crypto_ahash_type = {
88056ec3 HX	484	.extsize = crypto_ahash_extsize,
88056ec3 HX	485	.init_tfm = crypto_ahash_init_tfm,
004a403c LH	486	#ifdef CONFIG_PROC_FS
	487	.show = crypto_ahash_show,
	488	#endif
6238cbae	489	.report = crypto_ahash_report,
88056ec3 HX	490	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	491	.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
	492	.type = CRYPTO_ALG_TYPE_AHASH,
	493	.tfmsize = offsetof(struct crypto_ahash, base),
004a403c LH	494	};
	495	EXPORT_SYMBOL_GPL(crypto_ahash_type);
	496
88056ec3 HX	497	struct crypto_ahash crypto_alloc_ahash(const char alg_name, u32 type,
	498	u32 mask)
	499	{
	500	return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
	501	}
	502	EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
	503
01c2dece HX	504	static int ahash_prepare_alg(struct ahash_alg *alg)
	505	{
	506	struct crypto_alg *base = &alg->halg.base;
	507
	508	if (alg->halg.digestsize > PAGE_SIZE / 8 \|\|
	509	alg->halg.statesize > PAGE_SIZE / 8)
	510	return -EINVAL;
	511
	512	base->cra_type = &crypto_ahash_type;
	513	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	514	base->cra_flags \|= CRYPTO_ALG_TYPE_AHASH;
	515
	516	return 0;
	517	}
	518
	519	int crypto_register_ahash(struct ahash_alg *alg)
	520	{
	521	struct crypto_alg *base = &alg->halg.base;
	522	int err;
	523
	524	err = ahash_prepare_alg(alg);
	525	if (err)
	526	return err;
	527
	528	return crypto_register_alg(base);
	529	}
	530	EXPORT_SYMBOL_GPL(crypto_register_ahash);
	531
	532	int crypto_unregister_ahash(struct ahash_alg *alg)
	533	{
	534	return crypto_unregister_alg(&alg->halg.base);
	535	}
	536	EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
	537
	538	int ahash_register_instance(struct crypto_template *tmpl,
	539	struct ahash_instance *inst)
	540	{
	541	int err;
	542
	543	err = ahash_prepare_alg(&inst->alg);
	544	if (err)
	545	return err;
	546
	547	return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
	548	}
	549	EXPORT_SYMBOL_GPL(ahash_register_instance);
	550
	551	void ahash_free_instance(struct crypto_instance *inst)
	552	{
	553	crypto_drop_spawn(crypto_instance_ctx(inst));
	554	kfree(ahash_instance(inst));
	555	}
	556	EXPORT_SYMBOL_GPL(ahash_free_instance);
	557
	558	int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
	559	struct hash_alg_common *alg,
	560	struct crypto_instance *inst)
	561	{
	562	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
	563	&crypto_ahash_type);
	564	}
	565	EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
	566
	567	struct hash_alg_common ahash_attr_alg(struct rtattr rta, u32 type, u32 mask)
568	{
569	struct crypto_alg *alg;
570
571	alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
572	return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
573	}
574	EXPORT_SYMBOL_GPL(ahash_attr_alg);
575
004a403c LH	576	MODULE_LICENSE("GPL");
004a403c LH	577	MODULE_DESCRIPTION("Asynchronous cryptographic hash type");