[linux-2.6-block.git] / crypto / api.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 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.
 */

#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);
	return 0;
}

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_skcipher().
 *
 *	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_skcipher().
 *
 *	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");
MODULE_SOFTDEP("pre: cryptomgr");
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* Scatterlist Cryptographic API.
	4	*
	5	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
	6	* Copyright (c) 2002 David S. Miller (davem@redhat.com)
5cb1454b	7	* Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4 LT	8	*
1da177e4 LT	9	* Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
991d1740	10	* and Nettle, by Niels Möller.
1da177e4	11	*/
a61cc448	12
6bfd4809	13	#include <linux/err.h>
1da177e4	14	#include <linux/errno.h>
5cb1454b	15	#include <linux/kernel.h>
176c3652	16	#include <linux/kmod.h>
2b8c19db	17	#include <linux/module.h>
2825982d	18	#include <linux/param.h>
174cd4b1	19	#include <linux/sched/signal.h>
1da177e4	20	#include <linux/slab.h>
5cb1454b	21	#include <linux/string.h>
ada69a16	22	#include <linux/completion.h>
1da177e4 LT	23	#include "internal.h"
	24
	25	LIST_HEAD(crypto_alg_list);
cce9e06d	26	EXPORT_SYMBOL_GPL(crypto_alg_list);
1da177e4	27	DECLARE_RWSEM(crypto_alg_sem);
cce9e06d	28	EXPORT_SYMBOL_GPL(crypto_alg_sem);
1da177e4	29
2825982d HX	30	BLOCKING_NOTIFIER_HEAD(crypto_chain);
	31	EXPORT_SYMBOL_GPL(crypto_chain);
	32
77dbd7a9 HX	33	static struct crypto_alg crypto_larval_wait(struct crypto_alg alg);
77dbd7a9 HX	34
2825982d	35	struct crypto_alg crypto_mod_get(struct crypto_alg alg)
6521f302 HX	36	{
6521f302 HX	37	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
1da177e4	38	}
2825982d	39	EXPORT_SYMBOL_GPL(crypto_mod_get);
1da177e4	40
2825982d	41	void crypto_mod_put(struct crypto_alg *alg)
1da177e4	42	{
da7cd59a HX	43	struct module *module = alg->cra_module;
da7cd59a HX	44
6521f302	45	crypto_alg_put(alg);
da7cd59a	46	module_put(module);
1da177e4	47	}
2825982d	48	EXPORT_SYMBOL_GPL(crypto_mod_put);
1da177e4	49
73d3864a HX	50	static inline int crypto_is_test_larval(struct crypto_larval *larval)
	51	{
	52	return larval->alg.cra_driver_name[0];
	53	}
	54
c51b6c81 HX	55	static struct crypto_alg __crypto_alg_lookup(const char name, u32 type,
c51b6c81 HX	56	u32 mask)
1da177e4 LT	57	{
1da177e4 LT	58	struct crypto_alg q, alg = NULL;
2825982d	59	int best = -2;
1da177e4	60
1da177e4	61	list_for_each_entry(q, &crypto_alg_list, cra_list) {
5cb1454b HX	62	int exact, fuzzy;
5cb1454b HX	63
6bfd4809 HX	64	if (crypto_is_moribund(q))
	65	continue;
	66
492e2b63 HX	67	if ((q->cra_flags ^ type) & mask)
	68	continue;
	69
	70	if (crypto_is_larval(q) &&
73d3864a	71	!crypto_is_test_larval((struct crypto_larval *)q) &&
492e2b63 HX	72	((struct crypto_larval *)q)->mask != mask)
	73	continue;
	74
5cb1454b HX	75	exact = !strcmp(q->cra_driver_name, name);
	76	fuzzy = !strcmp(q->cra_name, name);
	77	if (!exact && !(fuzzy && q->cra_priority > best))
	78	continue;
	79
72fa4919	80	if (unlikely(!crypto_mod_get(q)))
5cb1454b HX	81	continue;
	82
	83	best = q->cra_priority;
	84	if (alg)
72fa4919	85	crypto_mod_put(alg);
5cb1454b HX	86	alg = q;
	87
	88	if (exact)
1da177e4	89	break;
1da177e4	90	}
2825982d HX	91
	92	return alg;
	93	}
2825982d HX	94
	95	static void crypto_larval_destroy(struct crypto_alg *alg)
	96	{
	97	struct crypto_larval larval = (void )alg;
	98
	99	BUG_ON(!crypto_is_larval(alg));
	100	if (larval->adult)
	101	crypto_mod_put(larval->adult);
	102	kfree(larval);
	103	}
	104
73d3864a	105	struct crypto_larval crypto_larval_alloc(const char name, u32 type, u32 mask)
2825982d	106	{
2825982d HX	107	struct crypto_larval *larval;
	108
	109	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
	110	if (!larval)
6bfd4809	111	return ERR_PTR(-ENOMEM);
2825982d	112
492e2b63 HX	113	larval->mask = mask;
492e2b63 HX	114	larval->alg.cra_flags = CRYPTO_ALG_LARVAL \| type;
2825982d HX	115	larval->alg.cra_priority = -1;
	116	larval->alg.cra_destroy = crypto_larval_destroy;
	117
2825982d HX	118	strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
	119	init_completion(&larval->completion);
	120
73d3864a HX	121	return larval;
	122	}
	123	EXPORT_SYMBOL_GPL(crypto_larval_alloc);
	124
	125	static struct crypto_alg crypto_larval_add(const char name, u32 type,
	126	u32 mask)
	127	{
	128	struct crypto_alg *alg;
	129	struct crypto_larval *larval;
	130
	131	larval = crypto_larval_alloc(name, type, mask);
	132	if (IS_ERR(larval))
	133	return ERR_CAST(larval);
	134
ce8614a3	135	refcount_set(&larval->alg.cra_refcnt, 2);
73d3864a	136
2825982d	137	down_write(&crypto_alg_sem);
492e2b63	138	alg = __crypto_alg_lookup(name, type, mask);
2825982d HX	139	if (!alg) {
	140	alg = &larval->alg;
	141	list_add(&alg->cra_list, &crypto_alg_list);
	142	}
	143	up_write(&crypto_alg_sem);
	144
77dbd7a9	145	if (alg != &larval->alg) {
2825982d	146	kfree(larval);
77dbd7a9 HX	147	if (crypto_is_larval(alg))
	148	alg = crypto_larval_wait(alg);
	149	}
2825982d HX	150
	151	return alg;
	152	}
	153
b9c55aa4	154	void crypto_larval_kill(struct crypto_alg *alg)
2825982d HX	155	{
	156	struct crypto_larval larval = (void )alg;
	157
	158	down_write(&crypto_alg_sem);
	159	list_del(&alg->cra_list);
	160	up_write(&crypto_alg_sem);
fe3c5206	161	complete_all(&larval->completion);
2825982d HX	162	crypto_alg_put(alg);
2825982d HX	163	}
b9c55aa4	164	EXPORT_SYMBOL_GPL(crypto_larval_kill);
2825982d HX	165
	166	static struct crypto_alg crypto_larval_wait(struct crypto_alg alg)
	167	{
	168	struct crypto_larval larval = (void )alg;
73d3864a HX	169	long timeout;
73d3864a HX	170
3fc89adb	171	timeout = wait_for_completion_killable_timeout(
73d3864a	172	&larval->completion, 60 * HZ);
2825982d	173
2825982d	174	alg = larval->adult;
73d3864a HX	175	if (timeout < 0)
	176	alg = ERR_PTR(-EINTR);
	177	else if (!timeout)
	178	alg = ERR_PTR(-ETIMEDOUT);
	179	else if (!alg)
6bfd4809	180	alg = ERR_PTR(-ENOENT);
73d3864a HX	181	else if (crypto_is_test_larval(larval) &&
	182	!(alg->cra_flags & CRYPTO_ALG_TESTED))
	183	alg = ERR_PTR(-EAGAIN);
	184	else if (!crypto_mod_get(alg))
	185	alg = ERR_PTR(-EAGAIN);
2825982d HX	186	crypto_mod_put(&larval->alg);
	187
	188	return alg;
	189	}
	190
3ca1e994 HX	191	static struct crypto_alg crypto_alg_lookup(const char name, u32 type,
3ca1e994 HX	192	u32 mask)
2825982d HX	193	{
2825982d HX	194	struct crypto_alg *alg;
eb02c38f HX	195	u32 test = 0;
	196
	197	if (!((type \| mask) & CRYPTO_ALG_TESTED))
	198	test \|= CRYPTO_ALG_TESTED;
2825982d	199
2825982d	200	down_read(&crypto_alg_sem);
eb02c38f	201	alg = __crypto_alg_lookup(name, type \| test, mask \| test);
b346e492 EB	202	if (!alg && test) {
	203	alg = __crypto_alg_lookup(name, type, mask);
	204	if (alg && !crypto_is_larval(alg)) {
	205	/* Test failed */
	206	crypto_mod_put(alg);
	207	alg = ERR_PTR(-ELIBBAD);
	208	}
	209	}
1da177e4	210	up_read(&crypto_alg_sem);
2825982d	211
1da177e4 LT	212	return alg;
	213	}
	214
cadc9ab5 EB	215	static struct crypto_alg crypto_larval_lookup(const char name, u32 type,
cadc9ab5 EB	216	u32 mask)
176c3652	217	{
2825982d	218	struct crypto_alg *alg;
2825982d	219
6bfd4809 HX	220	if (!name)
	221	return ERR_PTR(-ENOENT);
	222
430b441c	223	type &= ~(CRYPTO_ALG_LARVAL \| CRYPTO_ALG_DEAD);
6bfd4809	224	mask &= ~(CRYPTO_ALG_LARVAL \| CRYPTO_ALG_DEAD);
492e2b63	225
a760a665	226	alg = crypto_alg_lookup(name, type, mask);
e2861fa7	227	if (!alg && !(mask & CRYPTO_NOLOAD)) {
5d26a105	228	request_module("crypto-%s", name);
a760a665	229
37fc334c	230	if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
aa07a699	231	CRYPTO_ALG_NEED_FALLBACK))
5d26a105	232	request_module("crypto-%s-all", name);
a760a665 HX	233
	234	alg = crypto_alg_lookup(name, type, mask);
	235	}
	236
eb02c38f HX	237	if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
	238	alg = crypto_larval_wait(alg);
	239	else if (!alg)
	240	alg = crypto_larval_add(name, type, mask);
2825982d	241
eb02c38f	242	return alg;
b9c55aa4	243	}
b9c55aa4	244
73d3864a HX	245	int crypto_probing_notify(unsigned long val, void *v)
	246	{
	247	int ok;
	248
	249	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	250	if (ok == NOTIFY_DONE) {
	251	request_module("cryptomgr");
	252	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
	253	}
	254
	255	return ok;
	256	}
	257	EXPORT_SYMBOL_GPL(crypto_probing_notify);
	258
b9c55aa4 HX	259	struct crypto_alg crypto_alg_mod_lookup(const char name, u32 type, u32 mask)
	260	{
	261	struct crypto_alg *alg;
	262	struct crypto_alg *larval;
	263	int ok;
	264
06ca7f68 SM	265	/*
	266	* If the internal flag is set for a cipher, require a caller to
	267	* to invoke the cipher with the internal flag to use that cipher.
	268	* Also, if a caller wants to allocate a cipher that may or may
	269	* not be an internal cipher, use type \| CRYPTO_ALG_INTERNAL and
	270	* !(mask & CRYPTO_ALG_INTERNAL).
	271	*/
	272	if (!((type \| mask) & CRYPTO_ALG_INTERNAL))
	273	mask \|= CRYPTO_ALG_INTERNAL;
	274
b9c55aa4	275	larval = crypto_larval_lookup(name, type, mask);
6bfd4809	276	if (IS_ERR(larval) \|\| !crypto_is_larval(larval))
2825982d HX	277	return larval;
2825982d HX	278
73d3864a	279	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
2b8c19db HX	280
2b8c19db HX	281	if (ok == NOTIFY_STOP)
2825982d HX	282	alg = crypto_larval_wait(larval);
	283	else {
	284	crypto_mod_put(larval);
6bfd4809	285	alg = ERR_PTR(-ENOENT);
2825982d HX	286	}
	287	crypto_larval_kill(larval);
	288	return alg;
176c3652	289	}
492e2b63	290	EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
176c3652	291
27d2a330	292	static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
1da177e4	293	{
27d2a330	294	const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
e853c3cf	295
27d2a330 HX	296	if (type_obj)
27d2a330 HX	297	return type_obj->init(tfm, type, mask);
e8cfed5e	298	return 0;
1da177e4 LT	299	}
	300
	301	static void crypto_exit_ops(struct crypto_tfm *tfm)
	302	{
e853c3cf HX	303	const struct crypto_type *type = tfm->__crt_alg->cra_type;
e853c3cf HX	304
9c8ae17b EB	305	if (type && tfm->exit)
9c8ae17b EB	306	tfm->exit(tfm);
1da177e4 LT	307	}
1da177e4 LT	308
27d2a330	309	static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
fbdae9f3	310	{
27d2a330	311	const struct crypto_type *type_obj = alg->cra_type;
fbdae9f3 HX	312	unsigned int len;
fbdae9f3 HX	313
e853c3cf	314	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
27d2a330 HX	315	if (type_obj)
27d2a330 HX	316	return len + type_obj->ctxsize(alg, type, mask);
e853c3cf	317
fbdae9f3 HX	318	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
	319	default:
	320	BUG();
	321
	322	case CRYPTO_ALG_TYPE_CIPHER:
f1ddcaf3	323	len += crypto_cipher_ctxsize(alg);
fbdae9f3	324	break;
6941c3a0	325
fbdae9f3	326	case CRYPTO_ALG_TYPE_COMPRESS:
f1ddcaf3	327	len += crypto_compress_ctxsize(alg);
fbdae9f3 HX	328	break;
	329	}
	330
e853c3cf	331	return len;
fbdae9f3 HX	332	}
fbdae9f3 HX	333
6bfd4809 HX	334	void crypto_shoot_alg(struct crypto_alg *alg)
	335	{
	336	down_write(&crypto_alg_sem);
	337	alg->cra_flags \|= CRYPTO_ALG_DYING;
	338	up_write(&crypto_alg_sem);
	339	}
	340	EXPORT_SYMBOL_GPL(crypto_shoot_alg);
	341
27d2a330 HX	342	struct crypto_tfm __crypto_alloc_tfm(struct crypto_alg alg, u32 type,
27d2a330 HX	343	u32 mask)
1da177e4 LT	344	{
1da177e4 LT	345	struct crypto_tfm *tfm = NULL;
fbdae9f3	346	unsigned int tfm_size;
6bfd4809	347	int err = -ENOMEM;
fbdae9f3	348
27d2a330	349	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
bbeb563f	350	tfm = kzalloc(tfm_size, GFP_KERNEL);
1da177e4	351	if (tfm == NULL)
9765d262	352	goto out_err;
1da177e4	353
1da177e4	354	tfm->__crt_alg = alg;
6bfd4809	355
27d2a330	356	err = crypto_init_ops(tfm, type, mask);
6bfd4809	357	if (err)
1da177e4	358	goto out_free_tfm;
c7fc0599	359
4a779486	360	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
c7fc0599	361	goto cra_init_failed;
1da177e4 LT	362
	363	goto out;
	364
c7fc0599 HX	365	cra_init_failed:
c7fc0599 HX	366	crypto_exit_ops(tfm);
1da177e4	367	out_free_tfm:
4a779486 HX	368	if (err == -EAGAIN)
4a779486 HX	369	crypto_shoot_alg(alg);
1da177e4	370	kfree(tfm);
9765d262	371	out_err:
6bfd4809	372	tfm = ERR_PTR(err);
1da177e4 LT	373	out:
	374	return tfm;
	375	}
6bfd4809 HX	376	EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
6bfd4809 HX	377
6d7d684d HX	378	/*
	379	* crypto_alloc_base - Locate algorithm and allocate transform
	380	* @alg_name: Name of algorithm
	381	* @type: Type of algorithm
	382	* @mask: Mask for type comparison
	383	*
7b0bac64	384	* This function should not be used by new algorithm types.
fd1a1900	385	* Please use crypto_alloc_tfm instead.
7b0bac64	386	*
6d7d684d HX	387	* crypto_alloc_base() will first attempt to locate an already loaded
	388	* algorithm. If that fails and the kernel supports dynamically loadable
	389	* modules, it will then attempt to load a module of the same name or
	390	* alias. If that fails it will send a query to any loaded crypto manager
	391	* to construct an algorithm on the fly. A refcount is grabbed on the
	392	* algorithm which is then associated with the new transform.
	393	*
	394	* The returned transform is of a non-determinate type. Most people
	395	* should use one of the more specific allocation functions such as
c65058b7	396	* crypto_alloc_skcipher().
6d7d684d HX	397	*
	398	* In case of error the return value is an error pointer.
	399	*/
	400	struct crypto_tfm crypto_alloc_base(const char alg_name, u32 type, u32 mask)
	401	{
	402	struct crypto_tfm *tfm;
	403	int err;
	404
	405	for (;;) {
	406	struct crypto_alg *alg;
	407
	408	alg = crypto_alg_mod_lookup(alg_name, type, mask);
9765d262 AM	409	if (IS_ERR(alg)) {
9765d262 AM	410	err = PTR_ERR(alg);
6d7d684d	411	goto err;
9765d262	412	}
6d7d684d	413
27d2a330	414	tfm = __crypto_alloc_tfm(alg, type, mask);
6d7d684d	415	if (!IS_ERR(tfm))
9765d262	416	return tfm;
6d7d684d HX	417
	418	crypto_mod_put(alg);
	419	err = PTR_ERR(tfm);
	420
	421	err:
	422	if (err != -EAGAIN)
	423	break;
3fc89adb	424	if (fatal_signal_pending(current)) {
6d7d684d HX	425	err = -EINTR;
	426	break;
	427	}
9765d262	428	}
6d7d684d	429
9765d262	430	return ERR_PTR(err);
6d7d684d HX	431	}
6d7d684d HX	432	EXPORT_SYMBOL_GPL(crypto_alloc_base);
7b0bac64	433
3f683d61 HX	434	void crypto_create_tfm(struct crypto_alg alg,
3f683d61 HX	435	const struct crypto_type *frontend)
7b0bac64 HX	436	{
	437	char *mem;
	438	struct crypto_tfm *tfm = NULL;
	439	unsigned int tfmsize;
	440	unsigned int total;
	441	int err = -ENOMEM;
	442
	443	tfmsize = frontend->tfmsize;
2ca33da1	444	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
7b0bac64 HX	445
	446	mem = kzalloc(total, GFP_KERNEL);
	447	if (mem == NULL)
	448	goto out_err;
	449
	450	tfm = (struct crypto_tfm *)(mem + tfmsize);
	451	tfm->__crt_alg = alg;
	452
2ca33da1	453	err = frontend->init_tfm(tfm);
7b0bac64 HX	454	if (err)
	455	goto out_free_tfm;
	456
	457	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
	458	goto cra_init_failed;
	459
	460	goto out;
	461
	462	cra_init_failed:
	463	crypto_exit_ops(tfm);
	464	out_free_tfm:
	465	if (err == -EAGAIN)
	466	crypto_shoot_alg(alg);
	467	kfree(mem);
	468	out_err:
3f683d61	469	mem = ERR_PTR(err);
7b0bac64	470	out:
3f683d61	471	return mem;
7b0bac64 HX	472	}
	473	EXPORT_SYMBOL_GPL(crypto_create_tfm);
	474
d06854f0 HX	475	struct crypto_alg crypto_find_alg(const char alg_name,
	476	const struct crypto_type *frontend,
	477	u32 type, u32 mask)
	478	{
d06854f0 HX	479	if (frontend) {
	480	type &= frontend->maskclear;
	481	mask &= frontend->maskclear;
	482	type \|= frontend->type;
	483	mask \|= frontend->maskset;
d06854f0 HX	484	}
d06854f0 HX	485
4989d4f0	486	return crypto_alg_mod_lookup(alg_name, type, mask);
d06854f0 HX	487	}
	488	EXPORT_SYMBOL_GPL(crypto_find_alg);
	489
7b0bac64 HX	490	/*
	491	* crypto_alloc_tfm - Locate algorithm and allocate transform
	492	* @alg_name: Name of algorithm
	493	* @frontend: Frontend algorithm type
	494	* @type: Type of algorithm
	495	* @mask: Mask for type comparison
	496	*
	497	* crypto_alloc_tfm() will first attempt to locate an already loaded
	498	* algorithm. If that fails and the kernel supports dynamically loadable
	499	* modules, it will then attempt to load a module of the same name or
	500	* alias. If that fails it will send a query to any loaded crypto manager
	501	* to construct an algorithm on the fly. A refcount is grabbed on the
	502	* algorithm which is then associated with the new transform.
	503	*
	504	* The returned transform is of a non-determinate type. Most people
	505	* should use one of the more specific allocation functions such as
0a940d4e	506	* crypto_alloc_skcipher().
7b0bac64 HX	507	*
	508	* In case of error the return value is an error pointer.
	509	*/
3f683d61 HX	510	void crypto_alloc_tfm(const char alg_name,
3f683d61 HX	511	const struct crypto_type *frontend, u32 type, u32 mask)
7b0bac64	512	{
3f683d61	513	void *tfm;
7b0bac64 HX	514	int err;
7b0bac64 HX	515
7b0bac64 HX	516	for (;;) {
	517	struct crypto_alg *alg;
	518
d06854f0	519	alg = crypto_find_alg(alg_name, frontend, type, mask);
7b0bac64 HX	520	if (IS_ERR(alg)) {
	521	err = PTR_ERR(alg);
	522	goto err;
	523	}
	524
	525	tfm = crypto_create_tfm(alg, frontend);
	526	if (!IS_ERR(tfm))
	527	return tfm;
	528
	529	crypto_mod_put(alg);
	530	err = PTR_ERR(tfm);
	531
	532	err:
	533	if (err != -EAGAIN)
	534	break;
3fc89adb	535	if (fatal_signal_pending(current)) {
7b0bac64 HX	536	err = -EINTR;
	537	break;
	538	}
	539	}
	540
	541	return ERR_PTR(err);
	542	}
	543	EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
7b2cd92a	544
6d7d684d	545	/*
7b2cd92a HX	546	* crypto_destroy_tfm - Free crypto transform
7b2cd92a HX	547	* @mem: Start of tfm slab
6d7d684d HX	548	* @tfm: Transform to free
6d7d684d HX	549	*
7b2cd92a	550	* This function frees up the transform and any associated resources,
6d7d684d HX	551	* then drops the refcount on the associated algorithm.
6d7d684d HX	552	*/
7b2cd92a	553	void crypto_destroy_tfm(void mem, struct crypto_tfm tfm)
1da177e4	554	{
a61cc448	555	struct crypto_alg *alg;
a61cc448	556
7b2cd92a	557	if (unlikely(!mem))
a61cc448 JJ	558	return;
	559
	560	alg = tfm->__crt_alg;
1da177e4	561
4a779486	562	if (!tfm->exit && alg->cra_exit)
c7fc0599	563	alg->cra_exit(tfm);
1da177e4	564	crypto_exit_ops(tfm);
72fa4919	565	crypto_mod_put(alg);
811d8f06	566	kzfree(mem);
1da177e4	567	}
7b2cd92a	568	EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
fce32d70 HX	569
	570	int crypto_has_alg(const char *name, u32 type, u32 mask)
	571	{
	572	int ret = 0;
	573	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
3d01a33b	574
fce32d70 HX	575	if (!IS_ERR(alg)) {
	576	crypto_mod_put(alg);
	577	ret = 1;
	578	}
3d01a33b	579
fce32d70 HX	580	return ret;
	581	}
	582	EXPORT_SYMBOL_GPL(crypto_has_alg);
c3715cb9	583
ada69a16 GBY	584	void crypto_req_done(struct crypto_async_request *req, int err)
	585	{
	586	struct crypto_wait *wait = req->data;
	587
	588	if (err == -EINPROGRESS)
	589	return;
	590
	591	wait->err = err;
	592	complete(&wait->completion);
	593	}
	594	EXPORT_SYMBOL_GPL(crypto_req_done);
	595
c3715cb9 SS	596	MODULE_DESCRIPTION("Cryptographic core API");
c3715cb9 SS	597	MODULE_LICENSE("GPL");
8ab23d54	598	MODULE_SOFTDEP("pre: cryptomgr");