[mirror_ubuntu-zesty-kernel.git] / crypto / cryptomgr.c

/*
 * Create default crypto algorithm instances.
 *
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * 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/crypto.h>
#include <linux/ctype.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/rtnetlink.h>
#include <linux/sched.h>
#include <linux/string.h>

#include "internal.h"

struct cryptomgr_param {
	struct rtattr *tb[CRYPTO_MAX_ATTRS + 2];

	struct {
		struct rtattr attr;
		struct crypto_attr_type data;
	} type;

	union {
		struct rtattr attr;
		struct {
			struct rtattr attr;
			struct crypto_attr_alg data;
		} alg;
		struct {
			struct rtattr attr;
			struct crypto_attr_u32 data;
		} nu32;
	} attrs[CRYPTO_MAX_ATTRS];

	char larval[CRYPTO_MAX_ALG_NAME];
	char template[CRYPTO_MAX_ALG_NAME];
};

static int cryptomgr_probe(void *data)
{
	struct cryptomgr_param *param = data;
	struct crypto_template *tmpl;
	struct crypto_instance *inst;
	int err;

	tmpl = crypto_lookup_template(param->template);
	if (!tmpl)
		goto err;

	do {
		inst = tmpl->alloc(param->tb);
		if (IS_ERR(inst))
			err = PTR_ERR(inst);
		else if ((err = crypto_register_instance(tmpl, inst)))
			tmpl->free(inst);
	} while (err == -EAGAIN && !signal_pending(current));

	crypto_tmpl_put(tmpl);

	if (err)
		goto err;

out:
	kfree(param);
	module_put_and_exit(0);

err:
	crypto_larval_error(param->larval, param->type.data.type,
			    param->type.data.mask);
	goto out;
}

static int cryptomgr_schedule_probe(struct crypto_larval *larval)
{
	struct task_struct *thread;
	struct cryptomgr_param *param;
	const char *name = larval->alg.cra_name;
	const char *p;
	unsigned int len;
	int i;

	if (!try_module_get(THIS_MODULE))
		goto err;

	param = kzalloc(sizeof(*param), GFP_KERNEL);
	if (!param)
		goto err_put_module;

	for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++)
		;

	len = p - name;
	if (!len || *p != '(')
		goto err_free_param;

	memcpy(param->template, name, len);

	i = 0;
	for (;;) {
		int notnum = 0;

		name = ++p;
		len = 0;

		for (; isalnum(*p) || *p == '-' || *p == '_'; p++)
			notnum |= !isdigit(*p);

		if (*p == '(') {
			int recursion = 0;

			for (;;) {
				if (!*++p)
					goto err_free_param;
				if (*p == '(')
					recursion++;
				else if (*p == ')' && !recursion--)
					break;
			}

			notnum = 1;
		}

		len = p - name;
		if (!len)
			goto err_free_param;

		if (notnum) {
			param->attrs[i].alg.attr.rta_len =
				sizeof(param->attrs[i].alg);
			param->attrs[i].alg.attr.rta_type = CRYPTOA_ALG;
			memcpy(param->attrs[i].alg.data.name, name, len);
		} else {
			param->attrs[i].nu32.attr.rta_len =
				sizeof(param->attrs[i].nu32);
			param->attrs[i].nu32.attr.rta_type = CRYPTOA_U32;
			param->attrs[i].nu32.data.num =
				simple_strtol(name, NULL, 0);
		}

		param->tb[i + 1] = &param->attrs[i].attr;
		i++;

		if (WARN_ON(i >= CRYPTO_MAX_ATTRS))
			goto err_free_param;

		if (*p == ')')
			break;

		if (*p != ',')
			goto err_free_param;
	}

	if (!i)
		goto err_free_param;

	param->tb[i + 1] = NULL;

	param->type.attr.rta_len = sizeof(param->type);
	param->type.attr.rta_type = CRYPTOA_TYPE;
	param->type.data.type = larval->alg.cra_flags;
	param->type.data.mask = larval->mask;
	param->tb[0] = &param->type.attr;

	memcpy(param->larval, larval->alg.cra_name, CRYPTO_MAX_ALG_NAME);

	thread = kthread_run(cryptomgr_probe, param, "cryptomgr");
	if (IS_ERR(thread))
		goto err_free_param;

	return NOTIFY_STOP;

err_free_param:
	kfree(param);
err_put_module:
	module_put(THIS_MODULE);
err:
	return NOTIFY_OK;
}

static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
			    void *data)
{
	switch (msg) {
	case CRYPTO_MSG_ALG_REQUEST:
		return cryptomgr_schedule_probe(data);
	}

	return NOTIFY_DONE;
}

static struct notifier_block cryptomgr_notifier = {
	.notifier_call = cryptomgr_notify,
};

static int __init cryptomgr_init(void)
{
	return crypto_register_notifier(&cryptomgr_notifier);
}

static void __exit cryptomgr_exit(void)
{
	int err = crypto_unregister_notifier(&cryptomgr_notifier);
	BUG_ON(err);
}

module_init(cryptomgr_init);
module_exit(cryptomgr_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Crypto Algorithm Manager");
Commit	Line	Data
2b8c19db HX	1	/*
	2	* Create default crypto algorithm instances.
	3	*
	4	* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License as published by the Free
	8	* Software Foundation; either version 2 of the License, or (at your option)
	9	* any later version.
	10	*
	11	*/
	12
	13	#include <linux/crypto.h>
	14	#include <linux/ctype.h>
	15	#include <linux/err.h>
	16	#include <linux/init.h>
cf02f5da	17	#include <linux/kthread.h>
2b8c19db HX	18	#include <linux/module.h>
	19	#include <linux/notifier.h>
	20	#include <linux/rtnetlink.h>
6bfd4809	21	#include <linux/sched.h>
2b8c19db	22	#include <linux/string.h>
2b8c19db HX	23
	24	#include "internal.h"
	25
	26	struct cryptomgr_param {
39e1ee01	27	struct rtattr *tb[CRYPTO_MAX_ATTRS + 2];
ebc610e5 HX	28
	29	struct {
	30	struct rtattr attr;
	31	struct crypto_attr_type data;
	32	} type;
	33
39e1ee01	34	union {
2b8c19db	35	struct rtattr attr;
39e1ee01 HX	36	struct {
	37	struct rtattr attr;
	38	struct crypto_attr_alg data;
	39	} alg;
	40	struct {
	41	struct rtattr attr;
	42	struct crypto_attr_u32 data;
	43	} nu32;
	44	} attrs[CRYPTO_MAX_ATTRS];
	45
	46	char larval[CRYPTO_MAX_ALG_NAME];
2b8c19db HX	47	char template[CRYPTO_MAX_ALG_NAME];
	48	};
	49
cf02f5da	50	static int cryptomgr_probe(void *data)
2b8c19db	51	{
cf02f5da	52	struct cryptomgr_param *param = data;
2b8c19db HX	53	struct crypto_template *tmpl;
2b8c19db HX	54	struct crypto_instance *inst;
6bfd4809	55	int err;
2b8c19db HX	56
	57	tmpl = crypto_lookup_template(param->template);
	58	if (!tmpl)
	59	goto err;
	60
6bfd4809	61	do {
ebc610e5	62	inst = tmpl->alloc(param->tb);
6bfd4809 HX	63	if (IS_ERR(inst))
	64	err = PTR_ERR(inst);
	65	else if ((err = crypto_register_instance(tmpl, inst)))
	66	tmpl->free(inst);
	67	} while (err == -EAGAIN && !signal_pending(current));
2b8c19db HX	68
	69	crypto_tmpl_put(tmpl);
	70
6bfd4809 HX	71	if (err)
	72	goto err;
	73
2b8c19db HX	74	out:
2b8c19db HX	75	kfree(param);
cf02f5da	76	module_put_and_exit(0);
2b8c19db HX	77
2b8c19db HX	78	err:
39e1ee01	79	crypto_larval_error(param->larval, param->type.data.type,
ebc610e5	80	param->type.data.mask);
2b8c19db HX	81	goto out;
	82	}
	83
	84	static int cryptomgr_schedule_probe(struct crypto_larval *larval)
	85	{
1605b847	86	struct task_struct *thread;
2b8c19db HX	87	struct cryptomgr_param *param;
	88	const char *name = larval->alg.cra_name;
	89	const char *p;
	90	unsigned int len;
39e1ee01	91	int i;
2b8c19db	92
cf02f5da HX	93	if (!try_module_get(THIS_MODULE))
	94	goto err;
	95
ebc610e5	96	param = kzalloc(sizeof(*param), GFP_KERNEL);
2b8c19db	97	if (!param)
cf02f5da	98	goto err_put_module;
2b8c19db HX	99
	100	for (p = name; isalnum(p) \|\| p == '-' \|\| *p == '_'; p++)
	101	;
	102
	103	len = p - name;
	104	if (!len \|\| *p != '(')
	105	goto err_free_param;
	106
	107	memcpy(param->template, name, len);
2b8c19db	108
39e1ee01 HX	109	i = 0;
	110	for (;;) {
	111	int notnum = 0;
2b8c19db	112
39e1ee01 HX	113	name = ++p;
	114	len = 0;
	115
	116	for (; isalnum(p) \|\| p == '-' \|\| *p == '_'; p++)
	117	notnum \|= !isdigit(*p);
	118
	119	if (*p == '(') {
	120	int recursion = 0;
	121
	122	for (;;) {
	123	if (!*++p)
	124	goto err_free_param;
	125	if (*p == '(')
	126	recursion++;
	127	else if (*p == ')' && !recursion--)
	128	break;
	129	}
	130
	131	notnum = 1;
	132	}
cf02f5da HX	133
cf02f5da HX	134	len = p - name;
39e1ee01 HX	135	if (!len)
	136	goto err_free_param;
	137
	138	if (notnum) {
	139	param->attrs[i].alg.attr.rta_len =
	140	sizeof(param->attrs[i].alg);
	141	param->attrs[i].alg.attr.rta_type = CRYPTOA_ALG;
	142	memcpy(param->attrs[i].alg.data.name, name, len);
	143	} else {
	144	param->attrs[i].nu32.attr.rta_len =
	145	sizeof(param->attrs[i].nu32);
	146	param->attrs[i].nu32.attr.rta_type = CRYPTOA_U32;
	147	param->attrs[i].nu32.data.num =
	148	simple_strtol(name, NULL, 0);
	149	}
	150
	151	param->tb[i + 1] = &param->attrs[i].attr;
	152	i++;
	153
	154	if (WARN_ON(i >= CRYPTO_MAX_ATTRS))
	155	goto err_free_param;
	156
	157	if (*p == ')')
	158	break;
	159
	160	if (*p != ',')
	161	goto err_free_param;
cf02f5da HX	162	}
cf02f5da HX	163
39e1ee01	164	if (!i)
2b8c19db HX	165	goto err_free_param;
2b8c19db HX	166
39e1ee01 HX	167	param->tb[i + 1] = NULL;
39e1ee01 HX	168
ebc610e5 HX	169	param->type.attr.rta_len = sizeof(param->type);
	170	param->type.attr.rta_type = CRYPTOA_TYPE;
	171	param->type.data.type = larval->alg.cra_flags;
	172	param->type.data.mask = larval->mask;
39e1ee01	173	param->tb[0] = &param->type.attr;
2b8c19db	174
39e1ee01	175	memcpy(param->larval, larval->alg.cra_name, CRYPTO_MAX_ALG_NAME);
2b8c19db	176
1605b847 HX	177	thread = kthread_run(cryptomgr_probe, param, "cryptomgr");
1605b847 HX	178	if (IS_ERR(thread))
cf02f5da	179	goto err_free_param;
2b8c19db HX	180
	181	return NOTIFY_STOP;
	182
	183	err_free_param:
	184	kfree(param);
cf02f5da HX	185	err_put_module:
cf02f5da HX	186	module_put(THIS_MODULE);
2b8c19db HX	187	err:
	188	return NOTIFY_OK;
	189	}
	190
	191	static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
	192	void *data)
	193	{
	194	switch (msg) {
	195	case CRYPTO_MSG_ALG_REQUEST:
	196	return cryptomgr_schedule_probe(data);
	197	}
	198
	199	return NOTIFY_DONE;
	200	}
	201
	202	static struct notifier_block cryptomgr_notifier = {
	203	.notifier_call = cryptomgr_notify,
	204	};
	205
	206	static int __init cryptomgr_init(void)
	207	{
	208	return crypto_register_notifier(&cryptomgr_notifier);
	209	}
	210
	211	static void __exit cryptomgr_exit(void)
	212	{
	213	int err = crypto_unregister_notifier(&cryptomgr_notifier);
	214	BUG_ON(err);
	215	}
	216
	217	module_init(cryptomgr_init);
	218	module_exit(cryptomgr_exit);
	219
	220	MODULE_LICENSE("GPL");
	221	MODULE_DESCRIPTION("Crypto Algorithm Manager");