[deliverable/linux.git] / crypto / api.c

/*
 * Scatterlist Cryptographic API.
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
 * and Nettle, by Niels Möller.
 *
 * 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 <linux/err.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/module.h>
#include <linux/param.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/string.h>
#include "internal.h"

LIST_HEAD(crypto_alg_list);
EXPORT_SYMBOL_GPL(crypto_alg_list);
DECLARE_RWSEM(crypto_alg_sem);
EXPORT_SYMBOL_GPL(crypto_alg_sem);

BLOCKING_NOTIFIER_HEAD(crypto_chain);
EXPORT_SYMBOL_GPL(crypto_chain);

static inline struct crypto_alg *crypto_alg_get(struct crypto_alg *alg)
{
	atomic_inc(&alg->cra_refcnt);
	return alg;
}

struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
{
	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
}
EXPORT_SYMBOL_GPL(crypto_mod_get);

void crypto_mod_put(struct crypto_alg *alg)
{
	struct module *module = alg->cra_module;

	crypto_alg_put(alg);
	module_put(module);
}
EXPORT_SYMBOL_GPL(crypto_mod_put);

static inline int crypto_is_test_larval(struct crypto_larval *larval)
{
	return larval->alg.cra_driver_name[0];
}

static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
					      u32 mask)
{
	struct crypto_alg *q, *alg = NULL;
	int best = -2;

	list_for_each_entry(q, &crypto_alg_list, cra_list) {
		int exact, fuzzy;

		if (crypto_is_moribund(q))
			continue;

		if ((q->cra_flags ^ type) & mask)
			continue;

		if (crypto_is_larval(q) &&
		    !crypto_is_test_larval((struct crypto_larval *)q) &&
		    ((struct crypto_larval *)q)->mask != mask)
			continue;

		exact = !strcmp(q->cra_driver_name, name);
		fuzzy = !strcmp(q->cra_name, name);
		if (!exact && !(fuzzy && q->cra_priority > best))
			continue;

		if (unlikely(!crypto_mod_get(q)))
			continue;

		best = q->cra_priority;
		if (alg)
			crypto_mod_put(alg);
		alg = q;

		if (exact)
			break;
	}

	return alg;
}

static void crypto_larval_destroy(struct crypto_alg *alg)
{
	struct crypto_larval *larval = (void *)alg;

	BUG_ON(!crypto_is_larval(alg));
	if (larval->adult)
		crypto_mod_put(larval->adult);
	kfree(larval);
}

struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
{
	struct crypto_larval *larval;

	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
	if (!larval)
		return ERR_PTR(-ENOMEM);

	larval->mask = mask;
	larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
	larval->alg.cra_priority = -1;
	larval->alg.cra_destroy = crypto_larval_destroy;

	strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
	init_completion(&larval->completion);

	return larval;
}
EXPORT_SYMBOL_GPL(crypto_larval_alloc);

static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
					    u32 mask)
{
	struct crypto_alg *alg;
	struct crypto_larval *larval;

	larval = crypto_larval_alloc(name, type, mask);
	if (IS_ERR(larval))
		return ERR_CAST(larval);

	atomic_set(&larval->alg.cra_refcnt, 2);

	down_write(&crypto_alg_sem);
	alg = __crypto_alg_lookup(name, type, mask);
	if (!alg) {
		alg = &larval->alg;
		list_add(&alg->cra_list, &crypto_alg_list);
	}
	up_write(&crypto_alg_sem);

	if (alg != &larval->alg)
		kfree(larval);

	return alg;
}

void crypto_larval_kill(struct crypto_alg *alg)
{
	struct crypto_larval *larval = (void *)alg;

	down_write(&crypto_alg_sem);
	list_del(&alg->cra_list);
	up_write(&crypto_alg_sem);
	complete_all(&larval->completion);
	crypto_alg_put(alg);
}
EXPORT_SYMBOL_GPL(crypto_larval_kill);

static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
{
	struct crypto_larval *larval = (void *)alg;
	long timeout;

	timeout = wait_for_completion_interruptible_timeout(
		&larval->completion, 60 * HZ);

	alg = larval->adult;
	if (timeout < 0)
		alg = ERR_PTR(-EINTR);
	else if (!timeout)
		alg = ERR_PTR(-ETIMEDOUT);
	else if (!alg)
		alg = ERR_PTR(-ENOENT);
	else if (crypto_is_test_larval(larval) &&
		 !(alg->cra_flags & CRYPTO_ALG_TESTED))
		alg = ERR_PTR(-EAGAIN);
	else if (!crypto_mod_get(alg))
		alg = ERR_PTR(-EAGAIN);
	crypto_mod_put(&larval->alg);

	return alg;
}

struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask)
{
	struct crypto_alg *alg;

	down_read(&crypto_alg_sem);
	alg = __crypto_alg_lookup(name, type, mask);
	up_read(&crypto_alg_sem);

	return alg;
}
EXPORT_SYMBOL_GPL(crypto_alg_lookup);

struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask)
{
	struct crypto_alg *alg;

	if (!name)
		return ERR_PTR(-ENOENT);

	mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
	type &= mask;

	alg = try_then_request_module(crypto_alg_lookup(name, type, mask),
				      name);
	if (alg)
		return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;

	return crypto_larval_add(name, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_larval_lookup);

int crypto_probing_notify(unsigned long val, void *v)
{
	int ok;

	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	if (ok == NOTIFY_DONE) {
		request_module("cryptomgr");
		ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	}

	return ok;
}
EXPORT_SYMBOL_GPL(crypto_probing_notify);

struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
{
	struct crypto_alg *alg;
	struct crypto_alg *larval;
	int ok;

	if (!(mask & CRYPTO_ALG_TESTED)) {
		type |= CRYPTO_ALG_TESTED;
		mask |= CRYPTO_ALG_TESTED;
	}

	larval = crypto_larval_lookup(name, type, mask);
	if (IS_ERR(larval) || !crypto_is_larval(larval))
		return larval;

	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);

	if (ok == NOTIFY_STOP)
		alg = crypto_larval_wait(larval);
	else {
		crypto_mod_put(larval);
		alg = ERR_PTR(-ENOENT);
	}
	crypto_larval_kill(larval);
	return alg;
}
EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);

static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
{
	const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;

	if (type_obj)
		return type_obj->init(tfm, type, mask);

	switch (crypto_tfm_alg_type(tfm)) {
	case CRYPTO_ALG_TYPE_CIPHER:
		return crypto_init_cipher_ops(tfm);
		
	case CRYPTO_ALG_TYPE_DIGEST:
		if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) !=
		    CRYPTO_ALG_TYPE_HASH_MASK)
			return crypto_init_digest_ops_async(tfm);
		else
			return crypto_init_digest_ops(tfm);

	case CRYPTO_ALG_TYPE_COMPRESS:
		return crypto_init_compress_ops(tfm);
	
	default:
		break;
	}
	
	BUG();
	return -EINVAL;
}

static void crypto_exit_ops(struct crypto_tfm *tfm)
{
	const struct crypto_type *type = tfm->__crt_alg->cra_type;

	if (type) {
		if (tfm->exit)
			tfm->exit(tfm);
		return;
	}

	switch (crypto_tfm_alg_type(tfm)) {
	case CRYPTO_ALG_TYPE_CIPHER:
		crypto_exit_cipher_ops(tfm);
		break;
		
	case CRYPTO_ALG_TYPE_DIGEST:
		crypto_exit_digest_ops(tfm);
		break;
		
	case CRYPTO_ALG_TYPE_COMPRESS:
		crypto_exit_compress_ops(tfm);
		break;
	
	default:
		BUG();
		
	}
}

static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
{
	const struct crypto_type *type_obj = alg->cra_type;
	unsigned int len;

	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
	if (type_obj)
		return len + type_obj->ctxsize(alg, type, mask);

	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
	default:
		BUG();

	case CRYPTO_ALG_TYPE_CIPHER:
		len += crypto_cipher_ctxsize(alg);
		break;
		
	case CRYPTO_ALG_TYPE_DIGEST:
		len += crypto_digest_ctxsize(alg);
		break;
		
	case CRYPTO_ALG_TYPE_COMPRESS:
		len += crypto_compress_ctxsize(alg);
		break;
	}

	return len;
}

void crypto_shoot_alg(struct crypto_alg *alg)
{
	down_write(&crypto_alg_sem);
	alg->cra_flags |= CRYPTO_ALG_DYING;
	up_write(&crypto_alg_sem);
}
EXPORT_SYMBOL_GPL(crypto_shoot_alg);

struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
				      u32 mask)
{
	struct crypto_tfm *tfm = NULL;
	unsigned int tfm_size;
	int err = -ENOMEM;

	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
	tfm = kzalloc(tfm_size, GFP_KERNEL);
	if (tfm == NULL)
		goto out_err;

	tfm->__crt_alg = alg;

	err = crypto_init_ops(tfm, type, mask);
	if (err)
		goto out_free_tfm;

	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
		goto cra_init_failed;

	goto out;

cra_init_failed:
	crypto_exit_ops(tfm);
out_free_tfm:
	if (err == -EAGAIN)
		crypto_shoot_alg(alg);
	kfree(tfm);
out_err:
	tfm = ERR_PTR(err);
out:
	return tfm;
}
EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);

/*
 *	crypto_alloc_base - Locate algorithm and allocate transform
 *	@alg_name: Name of algorithm
 *	@type: Type of algorithm
 *	@mask: Mask for type comparison
 *
 *	This function should not be used by new algorithm types.
 *	Plesae use crypto_alloc_tfm instead.
 *
 *	crypto_alloc_base() will first attempt to locate an already loaded
 *	algorithm.  If that fails and the kernel supports dynamically loadable
 *	modules, it will then attempt to load a module of the same name or
 *	alias.  If that fails it will send a query to any loaded crypto manager
 *	to construct an algorithm on the fly.  A refcount is grabbed on the
 *	algorithm which is then associated with the new transform.
 *
 *	The returned transform is of a non-determinate type.  Most people
 *	should use one of the more specific allocation functions such as
 *	crypto_alloc_blkcipher.
 *
 *	In case of error the return value is an error pointer.
 */
struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
{
	struct crypto_tfm *tfm;
	int err;

	for (;;) {
		struct crypto_alg *alg;

		alg = crypto_alg_mod_lookup(alg_name, type, mask);
		if (IS_ERR(alg)) {
			err = PTR_ERR(alg);
			goto err;
		}

		tfm = __crypto_alloc_tfm(alg, type, mask);
		if (!IS_ERR(tfm))
			return tfm;

		crypto_mod_put(alg);
		err = PTR_ERR(tfm);

err:
		if (err != -EAGAIN)
			break;
		if (signal_pending(current)) {
			err = -EINTR;
			break;
		}
	}

	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_alloc_base);

struct crypto_tfm *crypto_create_tfm(struct crypto_alg *alg,
				     const struct crypto_type *frontend)
{
	char *mem;
	struct crypto_tfm *tfm = NULL;
	unsigned int tfmsize;
	unsigned int total;
	int err = -ENOMEM;

	tfmsize = frontend->tfmsize;
	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg, frontend);

	mem = kzalloc(total, GFP_KERNEL);
	if (mem == NULL)
		goto out_err;

	tfm = (struct crypto_tfm *)(mem + tfmsize);
	tfm->__crt_alg = alg;

	err = frontend->init_tfm(tfm, frontend);
	if (err)
		goto out_free_tfm;

	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
		goto cra_init_failed;

	goto out;

cra_init_failed:
	crypto_exit_ops(tfm);
out_free_tfm:
	if (err == -EAGAIN)
		crypto_shoot_alg(alg);
	kfree(mem);
out_err:
	tfm = ERR_PTR(err);
out:
	return tfm;
}
EXPORT_SYMBOL_GPL(crypto_create_tfm);

/*
 *	crypto_alloc_tfm - Locate algorithm and allocate transform
 *	@alg_name: Name of algorithm
 *	@frontend: Frontend algorithm type
 *	@type: Type of algorithm
 *	@mask: Mask for type comparison
 *
 *	crypto_alloc_tfm() will first attempt to locate an already loaded
 *	algorithm.  If that fails and the kernel supports dynamically loadable
 *	modules, it will then attempt to load a module of the same name or
 *	alias.  If that fails it will send a query to any loaded crypto manager
 *	to construct an algorithm on the fly.  A refcount is grabbed on the
 *	algorithm which is then associated with the new transform.
 *
 *	The returned transform is of a non-determinate type.  Most people
 *	should use one of the more specific allocation functions such as
 *	crypto_alloc_blkcipher.
 *
 *	In case of error the return value is an error pointer.
 */
struct crypto_tfm *crypto_alloc_tfm(const char *alg_name,
				    const struct crypto_type *frontend,
				    u32 type, u32 mask)
{
	struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask);
	struct crypto_tfm *tfm;
	int err;

	type &= frontend->maskclear;
	mask &= frontend->maskclear;
	type |= frontend->type;
	mask |= frontend->maskset;

	lookup = frontend->lookup ?: crypto_alg_mod_lookup;

	for (;;) {
		struct crypto_alg *alg;

		alg = lookup(alg_name, type, mask);
		if (IS_ERR(alg)) {
			err = PTR_ERR(alg);
			goto err;
		}

		tfm = crypto_create_tfm(alg, frontend);
		if (!IS_ERR(tfm))
			return tfm;

		crypto_mod_put(alg);
		err = PTR_ERR(tfm);

err:
		if (err != -EAGAIN)
			break;
		if (signal_pending(current)) {
			err = -EINTR;
			break;
		}
	}

	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
 
/*
 *	crypto_free_tfm - Free crypto transform
 *	@tfm: Transform to free
 *
 *	crypto_free_tfm() frees up the transform and any associated resources,
 *	then drops the refcount on the associated algorithm.
 */
void crypto_free_tfm(struct crypto_tfm *tfm)
{
	struct crypto_alg *alg;
	int size;

	if (unlikely(!tfm))
		return;

	alg = tfm->__crt_alg;
	size = sizeof(*tfm) + alg->cra_ctxsize;

	if (!tfm->exit && alg->cra_exit)
		alg->cra_exit(tfm);
	crypto_exit_ops(tfm);
	crypto_mod_put(alg);
	memset(tfm, 0, size);
	kfree(tfm);
}

EXPORT_SYMBOL_GPL(crypto_free_tfm);

int crypto_has_alg(const char *name, u32 type, u32 mask)
{
	int ret = 0;
	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
	
	if (!IS_ERR(alg)) {
		crypto_mod_put(alg);
		ret = 1;
	}
	
	return ret;
}
EXPORT_SYMBOL_GPL(crypto_has_alg);

MODULE_DESCRIPTION("Cryptographic core API");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Scatterlist Cryptographic API.
	3	*
	4	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
	5	* Copyright (c) 2002 David S. Miller (davem@redhat.com)
5cb1454b	6	* Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4 LT	7	*
1da177e4 LT	8	* Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
991d1740	9	* and Nettle, by Niels Möller.
1da177e4 LT	10	*
	11	* This program is free software; you can redistribute it and/or modify it
	12	* under the terms of the GNU General Public License as published by the Free
	13	* Software Foundation; either version 2 of the License, or (at your option)
	14	* any later version.
	15	*
	16	*/
a61cc448	17
6bfd4809	18	#include <linux/err.h>
1da177e4	19	#include <linux/errno.h>
5cb1454b	20	#include <linux/kernel.h>
176c3652	21	#include <linux/kmod.h>
2b8c19db	22	#include <linux/module.h>
2825982d	23	#include <linux/param.h>
6bfd4809	24	#include <linux/sched.h>
1da177e4	25	#include <linux/slab.h>
5cb1454b	26	#include <linux/string.h>
1da177e4 LT	27	#include "internal.h"
	28
	29	LIST_HEAD(crypto_alg_list);
cce9e06d	30	EXPORT_SYMBOL_GPL(crypto_alg_list);
1da177e4	31	DECLARE_RWSEM(crypto_alg_sem);
cce9e06d	32	EXPORT_SYMBOL_GPL(crypto_alg_sem);
1da177e4	33
2825982d HX	34	BLOCKING_NOTIFIER_HEAD(crypto_chain);
	35	EXPORT_SYMBOL_GPL(crypto_chain);
	36
6521f302	37	static inline struct crypto_alg crypto_alg_get(struct crypto_alg alg)
1da177e4	38	{
6521f302 HX	39	atomic_inc(&alg->cra_refcnt);
	40	return alg;
	41	}
	42
2825982d	43	struct crypto_alg crypto_mod_get(struct crypto_alg alg)
6521f302 HX	44	{
6521f302 HX	45	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
1da177e4	46	}
2825982d	47	EXPORT_SYMBOL_GPL(crypto_mod_get);
1da177e4	48
2825982d	49	void crypto_mod_put(struct crypto_alg *alg)
1da177e4	50	{
da7cd59a HX	51	struct module *module = alg->cra_module;
da7cd59a HX	52
6521f302	53	crypto_alg_put(alg);
da7cd59a	54	module_put(module);
1da177e4	55	}
2825982d	56	EXPORT_SYMBOL_GPL(crypto_mod_put);
1da177e4	57
73d3864a HX	58	static inline int crypto_is_test_larval(struct crypto_larval *larval)
	59	{
	60	return larval->alg.cra_driver_name[0];
	61	}
	62
c51b6c81 HX	63	static struct crypto_alg __crypto_alg_lookup(const char name, u32 type,
c51b6c81 HX	64	u32 mask)
1da177e4 LT	65	{
1da177e4 LT	66	struct crypto_alg q, alg = NULL;
2825982d	67	int best = -2;
1da177e4	68
1da177e4	69	list_for_each_entry(q, &crypto_alg_list, cra_list) {
5cb1454b HX	70	int exact, fuzzy;
5cb1454b HX	71
6bfd4809 HX	72	if (crypto_is_moribund(q))
	73	continue;
	74
492e2b63 HX	75	if ((q->cra_flags ^ type) & mask)
	76	continue;
	77
	78	if (crypto_is_larval(q) &&
73d3864a	79	!crypto_is_test_larval((struct crypto_larval *)q) &&
492e2b63 HX	80	((struct crypto_larval *)q)->mask != mask)
	81	continue;
	82
5cb1454b HX	83	exact = !strcmp(q->cra_driver_name, name);
	84	fuzzy = !strcmp(q->cra_name, name);
	85	if (!exact && !(fuzzy && q->cra_priority > best))
	86	continue;
	87
72fa4919	88	if (unlikely(!crypto_mod_get(q)))
5cb1454b HX	89	continue;
	90
	91	best = q->cra_priority;
	92	if (alg)
72fa4919	93	crypto_mod_put(alg);
5cb1454b HX	94	alg = q;
	95
	96	if (exact)
1da177e4	97	break;
1da177e4	98	}
2825982d HX	99
	100	return alg;
	101	}
2825982d HX	102
	103	static void crypto_larval_destroy(struct crypto_alg *alg)
	104	{
	105	struct crypto_larval larval = (void )alg;
	106
	107	BUG_ON(!crypto_is_larval(alg));
	108	if (larval->adult)
	109	crypto_mod_put(larval->adult);
	110	kfree(larval);
	111	}
	112
73d3864a	113	struct crypto_larval crypto_larval_alloc(const char name, u32 type, u32 mask)
2825982d	114	{
2825982d HX	115	struct crypto_larval *larval;
	116
	117	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
	118	if (!larval)
6bfd4809	119	return ERR_PTR(-ENOMEM);
2825982d	120
492e2b63 HX	121	larval->mask = mask;
492e2b63 HX	122	larval->alg.cra_flags = CRYPTO_ALG_LARVAL \| type;
2825982d HX	123	larval->alg.cra_priority = -1;
	124	larval->alg.cra_destroy = crypto_larval_destroy;
	125
2825982d HX	126	strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
	127	init_completion(&larval->completion);
	128
73d3864a HX	129	return larval;
	130	}
	131	EXPORT_SYMBOL_GPL(crypto_larval_alloc);
	132
	133	static struct crypto_alg crypto_larval_add(const char name, u32 type,
	134	u32 mask)
	135	{
	136	struct crypto_alg *alg;
	137	struct crypto_larval *larval;
	138
	139	larval = crypto_larval_alloc(name, type, mask);
	140	if (IS_ERR(larval))
	141	return ERR_CAST(larval);
	142
	143	atomic_set(&larval->alg.cra_refcnt, 2);
	144
2825982d	145	down_write(&crypto_alg_sem);
492e2b63	146	alg = __crypto_alg_lookup(name, type, mask);
2825982d HX	147	if (!alg) {
	148	alg = &larval->alg;
	149	list_add(&alg->cra_list, &crypto_alg_list);
	150	}
	151	up_write(&crypto_alg_sem);
	152
	153	if (alg != &larval->alg)
	154	kfree(larval);
	155
	156	return alg;
	157	}
	158
b9c55aa4	159	void crypto_larval_kill(struct crypto_alg *alg)
2825982d HX	160	{
	161	struct crypto_larval larval = (void )alg;
	162
	163	down_write(&crypto_alg_sem);
	164	list_del(&alg->cra_list);
	165	up_write(&crypto_alg_sem);
fe3c5206	166	complete_all(&larval->completion);
2825982d HX	167	crypto_alg_put(alg);
2825982d HX	168	}
b9c55aa4	169	EXPORT_SYMBOL_GPL(crypto_larval_kill);
2825982d HX	170
	171	static struct crypto_alg crypto_larval_wait(struct crypto_alg alg)
	172	{
	173	struct crypto_larval larval = (void )alg;
73d3864a HX	174	long timeout;
	175
	176	timeout = wait_for_completion_interruptible_timeout(
	177	&larval->completion, 60 * HZ);
2825982d	178
2825982d	179	alg = larval->adult;
73d3864a HX	180	if (timeout < 0)
	181	alg = ERR_PTR(-EINTR);
	182	else if (!timeout)
	183	alg = ERR_PTR(-ETIMEDOUT);
	184	else if (!alg)
6bfd4809	185	alg = ERR_PTR(-ENOENT);
73d3864a HX	186	else if (crypto_is_test_larval(larval) &&
	187	!(alg->cra_flags & CRYPTO_ALG_TESTED))
	188	alg = ERR_PTR(-EAGAIN);
	189	else if (!crypto_mod_get(alg))
	190	alg = ERR_PTR(-EAGAIN);
2825982d HX	191	crypto_mod_put(&larval->alg);
	192
	193	return alg;
	194	}
	195
c51b6c81	196	struct crypto_alg crypto_alg_lookup(const char name, u32 type, u32 mask)
2825982d HX	197	{
	198	struct crypto_alg *alg;
	199
2825982d	200	down_read(&crypto_alg_sem);
492e2b63	201	alg = __crypto_alg_lookup(name, type, mask);
1da177e4	202	up_read(&crypto_alg_sem);
2825982d	203
1da177e4 LT	204	return alg;
1da177e4 LT	205	}
c51b6c81	206	EXPORT_SYMBOL_GPL(crypto_alg_lookup);
1da177e4	207
b9c55aa4	208	struct crypto_alg crypto_larval_lookup(const char name, u32 type, u32 mask)
176c3652	209	{
2825982d	210	struct crypto_alg *alg;
2825982d	211
6bfd4809 HX	212	if (!name)
	213	return ERR_PTR(-ENOENT);
	214
	215	mask &= ~(CRYPTO_ALG_LARVAL \| CRYPTO_ALG_DEAD);
492e2b63 HX	216	type &= mask;
	217
	218	alg = try_then_request_module(crypto_alg_lookup(name, type, mask),
	219	name);
2825982d HX	220	if (alg)
	221	return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
	222
73d3864a	223	return crypto_larval_add(name, type, mask);
b9c55aa4 HX	224	}
	225	EXPORT_SYMBOL_GPL(crypto_larval_lookup);
	226
73d3864a HX	227	int crypto_probing_notify(unsigned long val, void *v)
	228	{
	229	int ok;
	230
	231	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	232	if (ok == NOTIFY_DONE) {
	233	request_module("cryptomgr");
	234	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	235	}
	236
	237	return ok;
	238	}
	239	EXPORT_SYMBOL_GPL(crypto_probing_notify);
	240
b9c55aa4 HX	241	struct crypto_alg crypto_alg_mod_lookup(const char name, u32 type, u32 mask)
	242	{
	243	struct crypto_alg *alg;
	244	struct crypto_alg *larval;
	245	int ok;
	246
73d3864a HX	247	if (!(mask & CRYPTO_ALG_TESTED)) {
	248	type \|= CRYPTO_ALG_TESTED;
	249	mask \|= CRYPTO_ALG_TESTED;
	250	}
	251
b9c55aa4	252	larval = crypto_larval_lookup(name, type, mask);
6bfd4809	253	if (IS_ERR(larval) \|\| !crypto_is_larval(larval))
2825982d HX	254	return larval;
2825982d HX	255
73d3864a	256	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
2b8c19db HX	257
2b8c19db HX	258	if (ok == NOTIFY_STOP)
2825982d HX	259	alg = crypto_larval_wait(larval);
	260	else {
	261	crypto_mod_put(larval);
6bfd4809	262	alg = ERR_PTR(-ENOENT);
2825982d HX	263	}
	264	crypto_larval_kill(larval);
	265	return alg;
176c3652	266	}
492e2b63	267	EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
176c3652	268
27d2a330	269	static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
1da177e4	270	{
27d2a330	271	const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
e853c3cf	272
27d2a330 HX	273	if (type_obj)
27d2a330 HX	274	return type_obj->init(tfm, type, mask);
e853c3cf	275
1da177e4 LT	276	switch (crypto_tfm_alg_type(tfm)) {
	277	case CRYPTO_ALG_TYPE_CIPHER:
	278	return crypto_init_cipher_ops(tfm);
	279
	280	case CRYPTO_ALG_TYPE_DIGEST:
004a403c LH	281	if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) !=
	282	CRYPTO_ALG_TYPE_HASH_MASK)
	283	return crypto_init_digest_ops_async(tfm);
	284	else
	285	return crypto_init_digest_ops(tfm);
	286
1da177e4 LT	287	case CRYPTO_ALG_TYPE_COMPRESS:
	288	return crypto_init_compress_ops(tfm);
	289
	290	default:
	291	break;
	292	}
	293
	294	BUG();
	295	return -EINVAL;
	296	}
	297
	298	static void crypto_exit_ops(struct crypto_tfm *tfm)
	299	{
e853c3cf HX	300	const struct crypto_type *type = tfm->__crt_alg->cra_type;
	301
	302	if (type) {
4a779486 HX	303	if (tfm->exit)
4a779486 HX	304	tfm->exit(tfm);
e853c3cf HX	305	return;
	306	}
	307
1da177e4 LT	308	switch (crypto_tfm_alg_type(tfm)) {
	309	case CRYPTO_ALG_TYPE_CIPHER:
	310	crypto_exit_cipher_ops(tfm);
	311	break;
	312
	313	case CRYPTO_ALG_TYPE_DIGEST:
	314	crypto_exit_digest_ops(tfm);
	315	break;
	316
	317	case CRYPTO_ALG_TYPE_COMPRESS:
	318	crypto_exit_compress_ops(tfm);
	319	break;
	320
	321	default:
	322	BUG();
	323
	324	}
	325	}
	326
27d2a330	327	static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
fbdae9f3	328	{
27d2a330	329	const struct crypto_type *type_obj = alg->cra_type;
fbdae9f3 HX	330	unsigned int len;
fbdae9f3 HX	331
e853c3cf	332	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
27d2a330 HX	333	if (type_obj)
27d2a330 HX	334	return len + type_obj->ctxsize(alg, type, mask);
e853c3cf	335
fbdae9f3 HX	336	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
	337	default:
	338	BUG();
	339
	340	case CRYPTO_ALG_TYPE_CIPHER:
f1ddcaf3	341	len += crypto_cipher_ctxsize(alg);
fbdae9f3 HX	342	break;
	343
	344	case CRYPTO_ALG_TYPE_DIGEST:
f1ddcaf3	345	len += crypto_digest_ctxsize(alg);
fbdae9f3 HX	346	break;
	347
	348	case CRYPTO_ALG_TYPE_COMPRESS:
f1ddcaf3	349	len += crypto_compress_ctxsize(alg);
fbdae9f3 HX	350	break;
	351	}
	352
e853c3cf	353	return len;
fbdae9f3 HX	354	}
fbdae9f3 HX	355
6bfd4809 HX	356	void crypto_shoot_alg(struct crypto_alg *alg)
	357	{
	358	down_write(&crypto_alg_sem);
	359	alg->cra_flags \|= CRYPTO_ALG_DYING;
	360	up_write(&crypto_alg_sem);
	361	}
	362	EXPORT_SYMBOL_GPL(crypto_shoot_alg);
	363
27d2a330 HX	364	struct crypto_tfm __crypto_alloc_tfm(struct crypto_alg alg, u32 type,
27d2a330 HX	365	u32 mask)
1da177e4 LT	366	{
1da177e4 LT	367	struct crypto_tfm *tfm = NULL;
fbdae9f3	368	unsigned int tfm_size;
6bfd4809	369	int err = -ENOMEM;
fbdae9f3	370
27d2a330	371	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
bbeb563f	372	tfm = kzalloc(tfm_size, GFP_KERNEL);
1da177e4	373	if (tfm == NULL)
9765d262	374	goto out_err;
1da177e4	375
1da177e4	376	tfm->__crt_alg = alg;
6bfd4809	377
27d2a330	378	err = crypto_init_ops(tfm, type, mask);
6bfd4809	379	if (err)
1da177e4	380	goto out_free_tfm;
c7fc0599	381
4a779486	382	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
c7fc0599	383	goto cra_init_failed;
1da177e4 LT	384
	385	goto out;
	386
c7fc0599 HX	387	cra_init_failed:
c7fc0599 HX	388	crypto_exit_ops(tfm);
1da177e4	389	out_free_tfm:
4a779486 HX	390	if (err == -EAGAIN)
4a779486 HX	391	crypto_shoot_alg(alg);
1da177e4	392	kfree(tfm);
9765d262	393	out_err:
6bfd4809	394	tfm = ERR_PTR(err);
1da177e4 LT	395	out:
	396	return tfm;
	397	}
6bfd4809 HX	398	EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
6bfd4809 HX	399
6d7d684d HX	400	/*
	401	* crypto_alloc_base - Locate algorithm and allocate transform
	402	* @alg_name: Name of algorithm
	403	* @type: Type of algorithm
	404	* @mask: Mask for type comparison
	405	*
7b0bac64 HX	406	* This function should not be used by new algorithm types.
	407	* Plesae use crypto_alloc_tfm instead.
	408	*
6d7d684d HX	409	* crypto_alloc_base() will first attempt to locate an already loaded
	410	* algorithm. If that fails and the kernel supports dynamically loadable
	411	* modules, it will then attempt to load a module of the same name or
	412	* alias. If that fails it will send a query to any loaded crypto manager
	413	* to construct an algorithm on the fly. A refcount is grabbed on the
	414	* algorithm which is then associated with the new transform.
	415	*
	416	* The returned transform is of a non-determinate type. Most people
	417	* should use one of the more specific allocation functions such as
	418	* crypto_alloc_blkcipher.
	419	*
	420	* In case of error the return value is an error pointer.
	421	*/
	422	struct crypto_tfm crypto_alloc_base(const char alg_name, u32 type, u32 mask)
	423	{
	424	struct crypto_tfm *tfm;
	425	int err;
	426
	427	for (;;) {
	428	struct crypto_alg *alg;
	429
	430	alg = crypto_alg_mod_lookup(alg_name, type, mask);
9765d262 AM	431	if (IS_ERR(alg)) {
9765d262 AM	432	err = PTR_ERR(alg);
6d7d684d	433	goto err;
9765d262	434	}
6d7d684d	435
27d2a330	436	tfm = __crypto_alloc_tfm(alg, type, mask);
6d7d684d	437	if (!IS_ERR(tfm))
9765d262	438	return tfm;
6d7d684d HX	439
	440	crypto_mod_put(alg);
	441	err = PTR_ERR(tfm);
	442
	443	err:
	444	if (err != -EAGAIN)
	445	break;
	446	if (signal_pending(current)) {
	447	err = -EINTR;
	448	break;
	449	}
9765d262	450	}
6d7d684d	451
9765d262	452	return ERR_PTR(err);
6d7d684d HX	453	}
6d7d684d HX	454	EXPORT_SYMBOL_GPL(crypto_alloc_base);
7b0bac64 HX	455
	456	struct crypto_tfm crypto_create_tfm(struct crypto_alg alg,
	457	const struct crypto_type *frontend)
	458	{
	459	char *mem;
	460	struct crypto_tfm *tfm = NULL;
	461	unsigned int tfmsize;
	462	unsigned int total;
	463	int err = -ENOMEM;
	464
	465	tfmsize = frontend->tfmsize;
	466	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg, frontend);
	467
	468	mem = kzalloc(total, GFP_KERNEL);
	469	if (mem == NULL)
	470	goto out_err;
	471
	472	tfm = (struct crypto_tfm *)(mem + tfmsize);
	473	tfm->__crt_alg = alg;
	474
	475	err = frontend->init_tfm(tfm, frontend);
	476	if (err)
	477	goto out_free_tfm;
	478
	479	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
	480	goto cra_init_failed;
	481
	482	goto out;
	483
	484	cra_init_failed:
	485	crypto_exit_ops(tfm);
	486	out_free_tfm:
	487	if (err == -EAGAIN)
	488	crypto_shoot_alg(alg);
	489	kfree(mem);
	490	out_err:
	491	tfm = ERR_PTR(err);
	492	out:
	493	return tfm;
	494	}
	495	EXPORT_SYMBOL_GPL(crypto_create_tfm);
	496
	497	/*
	498	* crypto_alloc_tfm - Locate algorithm and allocate transform
	499	* @alg_name: Name of algorithm
	500	* @frontend: Frontend algorithm type
	501	* @type: Type of algorithm
	502	* @mask: Mask for type comparison
	503	*
	504	* crypto_alloc_tfm() will first attempt to locate an already loaded
	505	* algorithm. If that fails and the kernel supports dynamically loadable
	506	* modules, it will then attempt to load a module of the same name or
	507	* alias. If that fails it will send a query to any loaded crypto manager
	508	* to construct an algorithm on the fly. A refcount is grabbed on the
	509	* algorithm which is then associated with the new transform.
	510	*
	511	* The returned transform is of a non-determinate type. Most people
	512	* should use one of the more specific allocation functions such as
	513	* crypto_alloc_blkcipher.
	514	*
	515	* In case of error the return value is an error pointer.
	516	*/
	517	struct crypto_tfm crypto_alloc_tfm(const char alg_name,
	518	const struct crypto_type *frontend,
519	u32 type, u32 mask)
520	{
521	struct crypto_alg (lookup)(const char *name, u32 type, u32 mask);
522	struct crypto_tfm *tfm;
523	int err;
524
525	type &= frontend->maskclear;
526	mask &= frontend->maskclear;
527	type \|= frontend->type;
528	mask \|= frontend->maskset;
529
530	lookup = frontend->lookup ?: crypto_alg_mod_lookup;
531
532	for (;;) {
533	struct crypto_alg *alg;
534
535	alg = lookup(alg_name, type, mask);
536	if (IS_ERR(alg)) {
537	err = PTR_ERR(alg);
538	goto err;
539	}
540
541	tfm = crypto_create_tfm(alg, frontend);
542	if (!IS_ERR(tfm))
543	return tfm;
544
545	crypto_mod_put(alg);
546	err = PTR_ERR(tfm);
547
548	err:
549	if (err != -EAGAIN)
550	break;
551	if (signal_pending(current)) {
552	err = -EINTR;
553	break;
554	}
555	}
556
557	return ERR_PTR(err);
558	}
559	EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
6d7d684d HX	560
	561	/*
	562	* crypto_free_tfm - Free crypto transform
	563	* @tfm: Transform to free
	564	*
	565	* crypto_free_tfm() frees up the transform and any associated resources,
	566	* then drops the refcount on the associated algorithm.
	567	*/
1da177e4 LT	568	void crypto_free_tfm(struct crypto_tfm *tfm)
1da177e4 LT	569	{
a61cc448 JJ	570	struct crypto_alg *alg;
	571	int size;
	572
	573	if (unlikely(!tfm))
	574	return;
	575
	576	alg = tfm->__crt_alg;
	577	size = sizeof(*tfm) + alg->cra_ctxsize;
1da177e4	578
4a779486	579	if (!tfm->exit && alg->cra_exit)
c7fc0599	580	alg->cra_exit(tfm);
1da177e4	581	crypto_exit_ops(tfm);
72fa4919	582	crypto_mod_put(alg);
1da177e4 LT	583	memset(tfm, 0, size);
	584	kfree(tfm);
	585	}
	586
1da177e4	587	EXPORT_SYMBOL_GPL(crypto_free_tfm);
fce32d70 HX	588
	589	int crypto_has_alg(const char *name, u32 type, u32 mask)
	590	{
	591	int ret = 0;
	592	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
	593
	594	if (!IS_ERR(alg)) {
	595	crypto_mod_put(alg);
	596	ret = 1;
	597	}
	598
	599	return ret;
	600	}
	601	EXPORT_SYMBOL_GPL(crypto_has_alg);
c3715cb9 SS	602
	603	MODULE_DESCRIPTION("Cryptographic core API");
	604	MODULE_LICENSE("GPL");