[linux-2.6-block.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/signal.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/completion.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 struct crypto_alg *crypto_larval_wait(struct crypto_alg *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);

	refcount_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);
		if (crypto_is_larval(alg))
			alg = crypto_larval_wait(alg);
	}

	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_killable_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;
}

static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
					    u32 mask)
{
	struct crypto_alg *alg;
	u32 test = 0;

	if (!((type | mask) & CRYPTO_ALG_TESTED))
		test |= CRYPTO_ALG_TESTED;

	down_read(&crypto_alg_sem);
	alg = __crypto_alg_lookup(name, type | test, mask | test);
	if (!alg && test) {
		alg = __crypto_alg_lookup(name, type, mask);
		if (alg && !crypto_is_larval(alg)) {
			/* Test failed */
			crypto_mod_put(alg);
			alg = ERR_PTR(-ELIBBAD);
		}
	}
	up_read(&crypto_alg_sem);

	return alg;
}

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

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

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

	alg = crypto_alg_lookup(name, type, mask);
	if (!alg && !(mask & CRYPTO_NOLOAD)) {
		request_module("crypto-%s", name);

		if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
		      CRYPTO_ALG_NEED_FALLBACK))
			request_module("crypto-%s-all", name);

		alg = crypto_alg_lookup(name, type, mask);
	}

	if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
		alg = crypto_larval_wait(alg);
	else if (!alg)
		alg = crypto_larval_add(name, type, mask);

	return alg;
}

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 the internal flag is set for a cipher, require a caller to
	 * to invoke the cipher with the internal flag to use that cipher.
	 * Also, if a caller wants to allocate a cipher that may or may
	 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
	 * !(mask & CRYPTO_ALG_INTERNAL).
	 */
	if (!((type | mask) & CRYPTO_ALG_INTERNAL))
		mask |= CRYPTO_ALG_INTERNAL;

	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_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 && tfm->exit)
		tfm->exit(tfm);
}

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_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.
 *	Please 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 (fatal_signal_pending(current)) {
			err = -EINTR;
			break;
		}
	}

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

void *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);

	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);
	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:
	mem = ERR_PTR(err);
out:
	return mem;
}
EXPORT_SYMBOL_GPL(crypto_create_tfm);

struct crypto_alg *crypto_find_alg(const char *alg_name,
				   const struct crypto_type *frontend,
				   u32 type, u32 mask)
{
	if (frontend) {
		type &= frontend->maskclear;
		mask &= frontend->maskclear;
		type |= frontend->type;
		mask |= frontend->maskset;
	}

	return crypto_alg_mod_lookup(alg_name, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_find_alg);

/*
 *	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.
 */
void *crypto_alloc_tfm(const char *alg_name,
		       const struct crypto_type *frontend, u32 type, u32 mask)
{
	void *tfm;
	int err;

	for (;;) {
		struct crypto_alg *alg;

		alg = crypto_find_alg(alg_name, frontend, 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 (fatal_signal_pending(current)) {
			err = -EINTR;
			break;
		}
	}

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

/*
 *	crypto_destroy_tfm - Free crypto transform
 *	@mem: Start of tfm slab
 *	@tfm: Transform to free
 *
 *	This function frees up the transform and any associated resources,
 *	then drops the refcount on the associated algorithm.
 */
void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
{
	struct crypto_alg *alg;

	if (unlikely(!mem))
		return;

	alg = tfm->__crt_alg;

	if (!tfm->exit && alg->cra_exit)
		alg->cra_exit(tfm);
	crypto_exit_ops(tfm);
	crypto_mod_put(alg);
	kzfree(mem);
}
EXPORT_SYMBOL_GPL(crypto_destroy_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);

void crypto_req_done(struct crypto_async_request *req, int err)
{
	struct crypto_wait *wait = req->data;

	if (err == -EINPROGRESS)
		return;

	wait->err = err;
	complete(&wait->completion);
}
EXPORT_SYMBOL_GPL(crypto_req_done);

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
3d01a33b	13	* Software Foundation; either version 2 of the License, or (at your option)
1da177e4 LT	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>
174cd4b1	24	#include <linux/sched/signal.h>
1da177e4	25	#include <linux/slab.h>
5cb1454b	26	#include <linux/string.h>
ada69a16	27	#include <linux/completion.h>
1da177e4 LT	28	#include "internal.h"
	29
	30	LIST_HEAD(crypto_alg_list);
cce9e06d	31	EXPORT_SYMBOL_GPL(crypto_alg_list);
1da177e4	32	DECLARE_RWSEM(crypto_alg_sem);
cce9e06d	33	EXPORT_SYMBOL_GPL(crypto_alg_sem);
1da177e4	34
2825982d HX	35	BLOCKING_NOTIFIER_HEAD(crypto_chain);
	36	EXPORT_SYMBOL_GPL(crypto_chain);
	37
77dbd7a9 HX	38	static struct crypto_alg crypto_larval_wait(struct crypto_alg alg);
77dbd7a9 HX	39
2825982d	40	struct crypto_alg crypto_mod_get(struct crypto_alg alg)
6521f302 HX	41	{
6521f302 HX	42	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
1da177e4	43	}
2825982d	44	EXPORT_SYMBOL_GPL(crypto_mod_get);
1da177e4	45
2825982d	46	void crypto_mod_put(struct crypto_alg *alg)
1da177e4	47	{
da7cd59a HX	48	struct module *module = alg->cra_module;
da7cd59a HX	49
6521f302	50	crypto_alg_put(alg);
da7cd59a	51	module_put(module);
1da177e4	52	}
2825982d	53	EXPORT_SYMBOL_GPL(crypto_mod_put);
1da177e4	54
73d3864a HX	55	static inline int crypto_is_test_larval(struct crypto_larval *larval)
	56	{
	57	return larval->alg.cra_driver_name[0];
	58	}
	59
c51b6c81 HX	60	static struct crypto_alg __crypto_alg_lookup(const char name, u32 type,
c51b6c81 HX	61	u32 mask)
1da177e4 LT	62	{
1da177e4 LT	63	struct crypto_alg q, alg = NULL;
2825982d	64	int best = -2;
1da177e4	65
1da177e4	66	list_for_each_entry(q, &crypto_alg_list, cra_list) {
5cb1454b HX	67	int exact, fuzzy;
5cb1454b HX	68
6bfd4809 HX	69	if (crypto_is_moribund(q))
	70	continue;
	71
492e2b63 HX	72	if ((q->cra_flags ^ type) & mask)
	73	continue;
	74
	75	if (crypto_is_larval(q) &&
73d3864a	76	!crypto_is_test_larval((struct crypto_larval *)q) &&
492e2b63 HX	77	((struct crypto_larval *)q)->mask != mask)
	78	continue;
	79
5cb1454b HX	80	exact = !strcmp(q->cra_driver_name, name);
	81	fuzzy = !strcmp(q->cra_name, name);
	82	if (!exact && !(fuzzy && q->cra_priority > best))
	83	continue;
	84
72fa4919	85	if (unlikely(!crypto_mod_get(q)))
5cb1454b HX	86	continue;
	87
	88	best = q->cra_priority;
	89	if (alg)
72fa4919	90	crypto_mod_put(alg);
5cb1454b HX	91	alg = q;
	92
	93	if (exact)
1da177e4	94	break;
1da177e4	95	}
2825982d HX	96
	97	return alg;
	98	}
2825982d HX	99
	100	static void crypto_larval_destroy(struct crypto_alg *alg)
	101	{
	102	struct crypto_larval larval = (void )alg;
	103
	104	BUG_ON(!crypto_is_larval(alg));
	105	if (larval->adult)
	106	crypto_mod_put(larval->adult);
	107	kfree(larval);
	108	}
	109
73d3864a	110	struct crypto_larval crypto_larval_alloc(const char name, u32 type, u32 mask)
2825982d	111	{
2825982d HX	112	struct crypto_larval *larval;
	113
	114	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
	115	if (!larval)
6bfd4809	116	return ERR_PTR(-ENOMEM);
2825982d	117
492e2b63 HX	118	larval->mask = mask;
492e2b63 HX	119	larval->alg.cra_flags = CRYPTO_ALG_LARVAL \| type;
2825982d HX	120	larval->alg.cra_priority = -1;
	121	larval->alg.cra_destroy = crypto_larval_destroy;
	122
2825982d HX	123	strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
	124	init_completion(&larval->completion);
	125
73d3864a HX	126	return larval;
	127	}
	128	EXPORT_SYMBOL_GPL(crypto_larval_alloc);
	129
	130	static struct crypto_alg crypto_larval_add(const char name, u32 type,
	131	u32 mask)
	132	{
	133	struct crypto_alg *alg;
	134	struct crypto_larval *larval;
	135
	136	larval = crypto_larval_alloc(name, type, mask);
	137	if (IS_ERR(larval))
	138	return ERR_CAST(larval);
	139
ce8614a3	140	refcount_set(&larval->alg.cra_refcnt, 2);
73d3864a	141
2825982d	142	down_write(&crypto_alg_sem);
492e2b63	143	alg = __crypto_alg_lookup(name, type, mask);
2825982d HX	144	if (!alg) {
	145	alg = &larval->alg;
	146	list_add(&alg->cra_list, &crypto_alg_list);
	147	}
	148	up_write(&crypto_alg_sem);
	149
77dbd7a9	150	if (alg != &larval->alg) {
2825982d	151	kfree(larval);
77dbd7a9 HX	152	if (crypto_is_larval(alg))
	153	alg = crypto_larval_wait(alg);
	154	}
2825982d HX	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;
73d3864a HX	175
3fc89adb	176	timeout = wait_for_completion_killable_timeout(
73d3864a	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
3ca1e994 HX	196	static struct crypto_alg crypto_alg_lookup(const char name, u32 type,
3ca1e994 HX	197	u32 mask)
2825982d HX	198	{
2825982d HX	199	struct crypto_alg *alg;
eb02c38f HX	200	u32 test = 0;
	201
	202	if (!((type \| mask) & CRYPTO_ALG_TESTED))
	203	test \|= CRYPTO_ALG_TESTED;
2825982d	204
2825982d	205	down_read(&crypto_alg_sem);
eb02c38f	206	alg = __crypto_alg_lookup(name, type \| test, mask \| test);
b346e492 EB	207	if (!alg && test) {
	208	alg = __crypto_alg_lookup(name, type, mask);
	209	if (alg && !crypto_is_larval(alg)) {
	210	/* Test failed */
	211	crypto_mod_put(alg);
	212	alg = ERR_PTR(-ELIBBAD);
	213	}
	214	}
1da177e4	215	up_read(&crypto_alg_sem);
2825982d	216
1da177e4 LT	217	return alg;
	218	}
	219
cadc9ab5 EB	220	static struct crypto_alg crypto_larval_lookup(const char name, u32 type,
cadc9ab5 EB	221	u32 mask)
176c3652	222	{
2825982d	223	struct crypto_alg *alg;
2825982d	224
6bfd4809 HX	225	if (!name)
	226	return ERR_PTR(-ENOENT);
	227
430b441c	228	type &= ~(CRYPTO_ALG_LARVAL \| CRYPTO_ALG_DEAD);
6bfd4809	229	mask &= ~(CRYPTO_ALG_LARVAL \| CRYPTO_ALG_DEAD);
492e2b63	230
a760a665	231	alg = crypto_alg_lookup(name, type, mask);
e2861fa7	232	if (!alg && !(mask & CRYPTO_NOLOAD)) {
5d26a105	233	request_module("crypto-%s", name);
a760a665	234
37fc334c	235	if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
aa07a699	236	CRYPTO_ALG_NEED_FALLBACK))
5d26a105	237	request_module("crypto-%s-all", name);
a760a665 HX	238
	239	alg = crypto_alg_lookup(name, type, mask);
	240	}
	241
eb02c38f HX	242	if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
	243	alg = crypto_larval_wait(alg);
	244	else if (!alg)
	245	alg = crypto_larval_add(name, type, mask);
2825982d	246
eb02c38f	247	return alg;
b9c55aa4	248	}
b9c55aa4	249
73d3864a HX	250	int crypto_probing_notify(unsigned long val, void *v)
	251	{
	252	int ok;
	253
	254	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	255	if (ok == NOTIFY_DONE) {
	256	request_module("cryptomgr");
	257	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	258	}
	259
	260	return ok;
	261	}
	262	EXPORT_SYMBOL_GPL(crypto_probing_notify);
	263
b9c55aa4 HX	264	struct crypto_alg crypto_alg_mod_lookup(const char name, u32 type, u32 mask)
	265	{
	266	struct crypto_alg *alg;
	267	struct crypto_alg *larval;
	268	int ok;
	269
06ca7f68 SM	270	/*
	271	* If the internal flag is set for a cipher, require a caller to
	272	* to invoke the cipher with the internal flag to use that cipher.
	273	* Also, if a caller wants to allocate a cipher that may or may
	274	* not be an internal cipher, use type \| CRYPTO_ALG_INTERNAL and
	275	* !(mask & CRYPTO_ALG_INTERNAL).
	276	*/
	277	if (!((type \| mask) & CRYPTO_ALG_INTERNAL))
	278	mask \|= CRYPTO_ALG_INTERNAL;
	279
b9c55aa4	280	larval = crypto_larval_lookup(name, type, mask);
6bfd4809	281	if (IS_ERR(larval) \|\| !crypto_is_larval(larval))
2825982d HX	282	return larval;
2825982d HX	283
73d3864a	284	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
2b8c19db HX	285
2b8c19db HX	286	if (ok == NOTIFY_STOP)
2825982d HX	287	alg = crypto_larval_wait(larval);
	288	else {
	289	crypto_mod_put(larval);
6bfd4809	290	alg = ERR_PTR(-ENOENT);
2825982d HX	291	}
	292	crypto_larval_kill(larval);
	293	return alg;
176c3652	294	}
492e2b63	295	EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
176c3652	296
27d2a330	297	static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
1da177e4	298	{
27d2a330	299	const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
e853c3cf	300
27d2a330 HX	301	if (type_obj)
27d2a330 HX	302	return type_obj->init(tfm, type, mask);
e853c3cf	303
1da177e4 LT	304	switch (crypto_tfm_alg_type(tfm)) {
	305	case CRYPTO_ALG_TYPE_CIPHER:
	306	return crypto_init_cipher_ops(tfm);
004a403c	307
1da177e4 LT	308	case CRYPTO_ALG_TYPE_COMPRESS:
1da177e4 LT	309	return crypto_init_compress_ops(tfm);
3d01a33b	310
1da177e4 LT	311	default:
	312	break;
	313	}
3d01a33b	314
1da177e4 LT	315	BUG();
	316	return -EINVAL;
	317	}
	318
	319	static void crypto_exit_ops(struct crypto_tfm *tfm)
	320	{
e853c3cf HX	321	const struct crypto_type *type = tfm->__crt_alg->cra_type;
e853c3cf HX	322
9c8ae17b EB	323	if (type && tfm->exit)
9c8ae17b EB	324	tfm->exit(tfm);
1da177e4 LT	325	}
1da177e4 LT	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	342	break;
6941c3a0	343
fbdae9f3	344	case CRYPTO_ALG_TYPE_COMPRESS:
f1ddcaf3	345	len += crypto_compress_ctxsize(alg);
fbdae9f3 HX	346	break;
	347	}
	348
e853c3cf	349	return len;
fbdae9f3 HX	350	}
fbdae9f3 HX	351
6bfd4809 HX	352	void crypto_shoot_alg(struct crypto_alg *alg)
	353	{
	354	down_write(&crypto_alg_sem);
	355	alg->cra_flags \|= CRYPTO_ALG_DYING;
	356	up_write(&crypto_alg_sem);
	357	}
	358	EXPORT_SYMBOL_GPL(crypto_shoot_alg);
	359
27d2a330 HX	360	struct crypto_tfm __crypto_alloc_tfm(struct crypto_alg alg, u32 type,
27d2a330 HX	361	u32 mask)
1da177e4 LT	362	{
1da177e4 LT	363	struct crypto_tfm *tfm = NULL;
fbdae9f3	364	unsigned int tfm_size;
6bfd4809	365	int err = -ENOMEM;
fbdae9f3	366
27d2a330	367	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
bbeb563f	368	tfm = kzalloc(tfm_size, GFP_KERNEL);
1da177e4	369	if (tfm == NULL)
9765d262	370	goto out_err;
1da177e4	371
1da177e4	372	tfm->__crt_alg = alg;
6bfd4809	373
27d2a330	374	err = crypto_init_ops(tfm, type, mask);
6bfd4809	375	if (err)
1da177e4	376	goto out_free_tfm;
c7fc0599	377
4a779486	378	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
c7fc0599	379	goto cra_init_failed;
1da177e4 LT	380
	381	goto out;
	382
c7fc0599 HX	383	cra_init_failed:
c7fc0599 HX	384	crypto_exit_ops(tfm);
1da177e4	385	out_free_tfm:
4a779486 HX	386	if (err == -EAGAIN)
4a779486 HX	387	crypto_shoot_alg(alg);
1da177e4	388	kfree(tfm);
9765d262	389	out_err:
6bfd4809	390	tfm = ERR_PTR(err);
1da177e4 LT	391	out:
	392	return tfm;
	393	}
6bfd4809 HX	394	EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
6bfd4809 HX	395
6d7d684d HX	396	/*
	397	* crypto_alloc_base - Locate algorithm and allocate transform
	398	* @alg_name: Name of algorithm
	399	* @type: Type of algorithm
	400	* @mask: Mask for type comparison
	401	*
7b0bac64	402	* This function should not be used by new algorithm types.
fd1a1900	403	* Please use crypto_alloc_tfm instead.
7b0bac64	404	*
6d7d684d HX	405	* crypto_alloc_base() will first attempt to locate an already loaded
	406	* algorithm. If that fails and the kernel supports dynamically loadable
	407	* modules, it will then attempt to load a module of the same name or
	408	* alias. If that fails it will send a query to any loaded crypto manager
	409	* to construct an algorithm on the fly. A refcount is grabbed on the
	410	* algorithm which is then associated with the new transform.
	411	*
	412	* The returned transform is of a non-determinate type. Most people
	413	* should use one of the more specific allocation functions such as
	414	* crypto_alloc_blkcipher.
	415	*
	416	* In case of error the return value is an error pointer.
	417	*/
	418	struct crypto_tfm crypto_alloc_base(const char alg_name, u32 type, u32 mask)
	419	{
	420	struct crypto_tfm *tfm;
	421	int err;
	422
	423	for (;;) {
	424	struct crypto_alg *alg;
	425
	426	alg = crypto_alg_mod_lookup(alg_name, type, mask);
9765d262 AM	427	if (IS_ERR(alg)) {
9765d262 AM	428	err = PTR_ERR(alg);
6d7d684d	429	goto err;
9765d262	430	}
6d7d684d	431
27d2a330	432	tfm = __crypto_alloc_tfm(alg, type, mask);
6d7d684d	433	if (!IS_ERR(tfm))
9765d262	434	return tfm;
6d7d684d HX	435
	436	crypto_mod_put(alg);
	437	err = PTR_ERR(tfm);
	438
	439	err:
	440	if (err != -EAGAIN)
	441	break;
3fc89adb	442	if (fatal_signal_pending(current)) {
6d7d684d HX	443	err = -EINTR;
	444	break;
	445	}
9765d262	446	}
6d7d684d	447
9765d262	448	return ERR_PTR(err);
6d7d684d HX	449	}
6d7d684d HX	450	EXPORT_SYMBOL_GPL(crypto_alloc_base);
7b0bac64	451
3f683d61 HX	452	void crypto_create_tfm(struct crypto_alg alg,
3f683d61 HX	453	const struct crypto_type *frontend)
7b0bac64 HX	454	{
	455	char *mem;
	456	struct crypto_tfm *tfm = NULL;
	457	unsigned int tfmsize;
	458	unsigned int total;
	459	int err = -ENOMEM;
	460
	461	tfmsize = frontend->tfmsize;
2ca33da1	462	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
7b0bac64 HX	463
	464	mem = kzalloc(total, GFP_KERNEL);
	465	if (mem == NULL)
	466	goto out_err;
	467
	468	tfm = (struct crypto_tfm *)(mem + tfmsize);
	469	tfm->__crt_alg = alg;
	470
2ca33da1	471	err = frontend->init_tfm(tfm);
7b0bac64 HX	472	if (err)
	473	goto out_free_tfm;
	474
	475	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
	476	goto cra_init_failed;
	477
	478	goto out;
	479
	480	cra_init_failed:
	481	crypto_exit_ops(tfm);
	482	out_free_tfm:
	483	if (err == -EAGAIN)
	484	crypto_shoot_alg(alg);
	485	kfree(mem);
	486	out_err:
3f683d61	487	mem = ERR_PTR(err);
7b0bac64	488	out:
3f683d61	489	return mem;
7b0bac64 HX	490	}
	491	EXPORT_SYMBOL_GPL(crypto_create_tfm);
	492
d06854f0 HX	493	struct crypto_alg crypto_find_alg(const char alg_name,
	494	const struct crypto_type *frontend,
	495	u32 type, u32 mask)
	496	{
d06854f0 HX	497	if (frontend) {
	498	type &= frontend->maskclear;
	499	mask &= frontend->maskclear;
	500	type \|= frontend->type;
	501	mask \|= frontend->maskset;
d06854f0 HX	502	}
d06854f0 HX	503
4989d4f0	504	return crypto_alg_mod_lookup(alg_name, type, mask);
d06854f0 HX	505	}
	506	EXPORT_SYMBOL_GPL(crypto_find_alg);
	507
7b0bac64 HX	508	/*
	509	* crypto_alloc_tfm - Locate algorithm and allocate transform
	510	* @alg_name: Name of algorithm
	511	* @frontend: Frontend algorithm type
	512	* @type: Type of algorithm
	513	* @mask: Mask for type comparison
	514	*
	515	* crypto_alloc_tfm() will first attempt to locate an already loaded
	516	* algorithm. If that fails and the kernel supports dynamically loadable
	517	* modules, it will then attempt to load a module of the same name or
	518	* alias. If that fails it will send a query to any loaded crypto manager
	519	* to construct an algorithm on the fly. A refcount is grabbed on the
	520	* algorithm which is then associated with the new transform.
	521	*
	522	* The returned transform is of a non-determinate type. Most people
	523	* should use one of the more specific allocation functions such as
	524	* crypto_alloc_blkcipher.
	525	*
	526	* In case of error the return value is an error pointer.
	527	*/
3f683d61 HX	528	void crypto_alloc_tfm(const char alg_name,
3f683d61 HX	529	const struct crypto_type *frontend, u32 type, u32 mask)
7b0bac64	530	{
3f683d61	531	void *tfm;
7b0bac64 HX	532	int err;
7b0bac64 HX	533
7b0bac64 HX	534	for (;;) {
	535	struct crypto_alg *alg;
	536
d06854f0	537	alg = crypto_find_alg(alg_name, frontend, type, mask);
7b0bac64 HX	538	if (IS_ERR(alg)) {
	539	err = PTR_ERR(alg);
	540	goto err;
	541	}
	542
	543	tfm = crypto_create_tfm(alg, frontend);
	544	if (!IS_ERR(tfm))
	545	return tfm;
	546
	547	crypto_mod_put(alg);
	548	err = PTR_ERR(tfm);
	549
	550	err:
	551	if (err != -EAGAIN)
	552	break;
3fc89adb	553	if (fatal_signal_pending(current)) {
7b0bac64 HX	554	err = -EINTR;
	555	break;
	556	}
	557	}
	558
	559	return ERR_PTR(err);
	560	}
	561	EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
7b2cd92a	562
6d7d684d	563	/*
7b2cd92a HX	564	* crypto_destroy_tfm - Free crypto transform
7b2cd92a HX	565	* @mem: Start of tfm slab
6d7d684d HX	566	* @tfm: Transform to free
6d7d684d HX	567	*
7b2cd92a	568	* This function frees up the transform and any associated resources,
6d7d684d HX	569	* then drops the refcount on the associated algorithm.
6d7d684d HX	570	*/
7b2cd92a	571	void crypto_destroy_tfm(void mem, struct crypto_tfm tfm)
1da177e4	572	{
a61cc448	573	struct crypto_alg *alg;
a61cc448	574
7b2cd92a	575	if (unlikely(!mem))
a61cc448 JJ	576	return;
	577
	578	alg = tfm->__crt_alg;
1da177e4	579
4a779486	580	if (!tfm->exit && alg->cra_exit)
c7fc0599	581	alg->cra_exit(tfm);
1da177e4	582	crypto_exit_ops(tfm);
72fa4919	583	crypto_mod_put(alg);
811d8f06	584	kzfree(mem);
1da177e4	585	}
7b2cd92a	586	EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
fce32d70 HX	587
	588	int crypto_has_alg(const char *name, u32 type, u32 mask)
	589	{
	590	int ret = 0;
	591	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
3d01a33b	592
fce32d70 HX	593	if (!IS_ERR(alg)) {
	594	crypto_mod_put(alg);
	595	ret = 1;
	596	}
3d01a33b	597
fce32d70 HX	598	return ret;
	599	}
	600	EXPORT_SYMBOL_GPL(crypto_has_alg);
c3715cb9	601
ada69a16 GBY	602	void crypto_req_done(struct crypto_async_request *req, int err)
	603	{
	604	struct crypto_wait *wait = req->data;
	605
	606	if (err == -EINPROGRESS)
	607	return;
	608
	609	wait->err = err;
	610	complete(&wait->completion);
	611	}
	612	EXPORT_SYMBOL_GPL(crypto_req_done);
	613
c3715cb9 SS	614	MODULE_DESCRIPTION("Cryptographic core API");
c3715cb9 SS	615	MODULE_LICENSE("GPL");