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

/*
 * Crypto user configuration API.
 *
 * Copyright (C) 2011 secunet Security Networks AG
 * Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/module.h>
#include <linux/crypto.h>
#include <linux/cryptouser.h>
#include <linux/sched.h>
#include <net/netlink.h>
#include <linux/security.h>
#include <net/net_namespace.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h>

#include "internal.h"

#define null_terminated(x)	(strnlen(x, sizeof(x)) < sizeof(x))

static DEFINE_MUTEX(crypto_cfg_mutex);

/* The crypto netlink socket */
static struct sock *crypto_nlsk;

struct crypto_dump_info {
	struct sk_buff *in_skb;
	struct sk_buff *out_skb;
	u32 nlmsg_seq;
	u16 nlmsg_flags;
};

static struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact)
{
	struct crypto_alg *q, *alg = NULL;

	down_read(&crypto_alg_sem);

	list_for_each_entry(q, &crypto_alg_list, cra_list) {
		int match = 0;

		if ((q->cra_flags ^ p->cru_type) & p->cru_mask)
			continue;

		if (strlen(p->cru_driver_name))
			match = !strcmp(q->cra_driver_name,
					p->cru_driver_name);
		else if (!exact)
			match = !strcmp(q->cra_name, p->cru_name);

		if (!match)
			continue;

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

		alg = q;
		break;
	}

	up_read(&crypto_alg_sem);

	return alg;
}

static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_cipher rcipher;

	strncpy(rcipher.type, "cipher", sizeof(rcipher.type));

	rcipher.blocksize = alg->cra_blocksize;
	rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
	rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;

	if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
		    sizeof(struct crypto_report_cipher), &rcipher))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}

static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_comp rcomp;

	strncpy(rcomp.type, "compression", sizeof(rcomp.type));
	if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
		    sizeof(struct crypto_report_comp), &rcomp))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}

static int crypto_report_one(struct crypto_alg *alg,
			     struct crypto_user_alg *ualg, struct sk_buff *skb)
{
	strncpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
	strncpy(ualg->cru_driver_name, alg->cra_driver_name,
		sizeof(ualg->cru_driver_name));
	strncpy(ualg->cru_module_name, module_name(alg->cra_module),
		sizeof(ualg->cru_module_name));

	ualg->cru_type = 0;
	ualg->cru_mask = 0;
	ualg->cru_flags = alg->cra_flags;
	ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);

	if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
		goto nla_put_failure;
	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
		struct crypto_report_larval rl;

		strncpy(rl.type, "larval", sizeof(rl.type));
		if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL,
			    sizeof(struct crypto_report_larval), &rl))
			goto nla_put_failure;
		goto out;
	}

	if (alg->cra_type && alg->cra_type->report) {
		if (alg->cra_type->report(skb, alg))
			goto nla_put_failure;

		goto out;
	}

	switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_LARVAL)) {
	case CRYPTO_ALG_TYPE_CIPHER:
		if (crypto_report_cipher(skb, alg))
			goto nla_put_failure;

		break;
	case CRYPTO_ALG_TYPE_COMPRESS:
		if (crypto_report_comp(skb, alg))
			goto nla_put_failure;

		break;
	}

out:
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}

static int crypto_report_alg(struct crypto_alg *alg,
			     struct crypto_dump_info *info)
{
	struct sk_buff *in_skb = info->in_skb;
	struct sk_buff *skb = info->out_skb;
	struct nlmsghdr *nlh;
	struct crypto_user_alg *ualg;
	int err = 0;

	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
			CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
	if (!nlh) {
		err = -EMSGSIZE;
		goto out;
	}

	ualg = nlmsg_data(nlh);

	err = crypto_report_one(alg, ualg, skb);
	if (err) {
		nlmsg_cancel(skb, nlh);
		goto out;
	}

	nlmsg_end(skb, nlh);

out:
	return err;
}

static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
			 struct nlattr **attrs)
{
	struct crypto_user_alg *p = nlmsg_data(in_nlh);
	struct crypto_alg *alg;
	struct sk_buff *skb;
	struct crypto_dump_info info;
	int err;

	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
		return -EINVAL;

	alg = crypto_alg_match(p, 0);
	if (!alg)
		return -ENOENT;

	err = -ENOMEM;
	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
	if (!skb)
		goto drop_alg;

	info.in_skb = in_skb;
	info.out_skb = skb;
	info.nlmsg_seq = in_nlh->nlmsg_seq;
	info.nlmsg_flags = 0;

	err = crypto_report_alg(alg, &info);

drop_alg:
	crypto_mod_put(alg);

	if (err)
		return err;

	return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
}

static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct crypto_alg *alg;
	struct crypto_dump_info info;
	int err;

	if (cb->args[0])
		goto out;

	cb->args[0] = 1;

	info.in_skb = cb->skb;
	info.out_skb = skb;
	info.nlmsg_seq = cb->nlh->nlmsg_seq;
	info.nlmsg_flags = NLM_F_MULTI;

	list_for_each_entry(alg, &crypto_alg_list, cra_list) {
		err = crypto_report_alg(alg, &info);
		if (err)
			goto out_err;
	}

out:
	return skb->len;
out_err:
	return err;
}

static int crypto_dump_report_done(struct netlink_callback *cb)
{
	return 0;
}

static int crypto_update_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
			     struct nlattr **attrs)
{
	struct crypto_alg *alg;
	struct crypto_user_alg *p = nlmsg_data(nlh);
	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	LIST_HEAD(list);

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
		return -EINVAL;

	if (priority && !strlen(p->cru_driver_name))
		return -EINVAL;

	alg = crypto_alg_match(p, 1);
	if (!alg)
		return -ENOENT;

	down_write(&crypto_alg_sem);

	crypto_remove_spawns(alg, &list, NULL);

	if (priority)
		alg->cra_priority = nla_get_u32(priority);

	up_write(&crypto_alg_sem);

	crypto_mod_put(alg);
	crypto_remove_final(&list);

	return 0;
}

static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
			  struct nlattr **attrs)
{
	struct crypto_alg *alg;
	struct crypto_user_alg *p = nlmsg_data(nlh);
	int err;

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
		return -EINVAL;

	alg = crypto_alg_match(p, 1);
	if (!alg)
		return -ENOENT;

	/* We can not unregister core algorithms such as aes-generic.
	 * We would loose the reference in the crypto_alg_list to this algorithm
	 * if we try to unregister. Unregistering such an algorithm without
	 * removing the module is not possible, so we restrict to crypto
	 * instances that are build from templates. */
	err = -EINVAL;
	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
		goto drop_alg;

	err = -EBUSY;
	if (atomic_read(&alg->cra_refcnt) > 2)
		goto drop_alg;

	err = crypto_unregister_instance((struct crypto_instance *)alg);

drop_alg:
	crypto_mod_put(alg);
	return err;
}

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

	type = crypto_skcipher_type(type);
	mask = crypto_skcipher_mask(mask);

	for (;;) {
		alg = crypto_lookup_skcipher(name,  type, mask);
		if (!IS_ERR(alg))
			return alg;

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

	return ERR_PTR(err);
}

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

	type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
	type |= CRYPTO_ALG_TYPE_AEAD;
	mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
	mask |= CRYPTO_ALG_TYPE_MASK;

	for (;;) {
		alg = crypto_lookup_aead(name,  type, mask);
		if (!IS_ERR(alg))
			return alg;

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

	return ERR_PTR(err);
}

static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
			  struct nlattr **attrs)
{
	int exact = 0;
	const char *name;
	struct crypto_alg *alg;
	struct crypto_user_alg *p = nlmsg_data(nlh);
	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
		return -EINVAL;

	if (strlen(p->cru_driver_name))
		exact = 1;

	if (priority && !exact)
		return -EINVAL;

	alg = crypto_alg_match(p, exact);
	if (alg) {
		crypto_mod_put(alg);
		return -EEXIST;
	}

	if (strlen(p->cru_driver_name))
		name = p->cru_driver_name;
	else
		name = p->cru_name;

	switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) {
	case CRYPTO_ALG_TYPE_AEAD:
		alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask);
		break;
	case CRYPTO_ALG_TYPE_GIVCIPHER:
	case CRYPTO_ALG_TYPE_BLKCIPHER:
	case CRYPTO_ALG_TYPE_ABLKCIPHER:
		alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask);
		break;
	default:
		alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
	}

	if (IS_ERR(alg))
		return PTR_ERR(alg);

	down_write(&crypto_alg_sem);

	if (priority)
		alg->cra_priority = nla_get_u32(priority);

	up_write(&crypto_alg_sem);

	crypto_mod_put(alg);

	return 0;
}

#define MSGSIZE(type) sizeof(struct type)

static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
	[CRYPTO_MSG_NEWALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	[CRYPTO_MSG_DELALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	[CRYPTO_MSG_UPDATEALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	[CRYPTO_MSG_GETALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
};

static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
	[CRYPTOCFGA_PRIORITY_VAL]   = { .type = NLA_U32},
};

#undef MSGSIZE

static const struct crypto_link {
	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
	int (*dump)(struct sk_buff *, struct netlink_callback *);
	int (*done)(struct netlink_callback *);
} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
	[CRYPTO_MSG_NEWALG	- CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
	[CRYPTO_MSG_DELALG	- CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
	[CRYPTO_MSG_UPDATEALG	- CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
	[CRYPTO_MSG_GETALG	- CRYPTO_MSG_BASE] = { .doit = crypto_report,
						       .dump = crypto_dump_report,
						       .done = crypto_dump_report_done},
};

static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
	struct nlattr *attrs[CRYPTOCFGA_MAX+1];
	const struct crypto_link *link;
	int type, err;

	type = nlh->nlmsg_type;
	if (type > CRYPTO_MSG_MAX)
		return -EINVAL;

	type -= CRYPTO_MSG_BASE;
	link = &crypto_dispatch[type];

	if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
	    (nlh->nlmsg_flags & NLM_F_DUMP))) {
		struct crypto_alg *alg;
		u16 dump_alloc = 0;

		if (link->dump == NULL)
			return -EINVAL;

		list_for_each_entry(alg, &crypto_alg_list, cra_list)
			dump_alloc += CRYPTO_REPORT_MAXSIZE;

		{
			struct netlink_dump_control c = {
				.dump = link->dump,
				.done = link->done,
				.min_dump_alloc = dump_alloc,
			};
			return netlink_dump_start(crypto_nlsk, skb, nlh, &c);
		}
	}

	err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
			  crypto_policy);
	if (err < 0)
		return err;

	if (link->doit == NULL)
		return -EINVAL;

	return link->doit(skb, nlh, attrs);
}

static void crypto_netlink_rcv(struct sk_buff *skb)
{
	mutex_lock(&crypto_cfg_mutex);
	netlink_rcv_skb(skb, &crypto_user_rcv_msg);
	mutex_unlock(&crypto_cfg_mutex);
}

static int __init crypto_user_init(void)
{
	struct netlink_kernel_cfg cfg = {
		.input	= crypto_netlink_rcv,
	};

	crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg);
	if (!crypto_nlsk)
		return -ENOMEM;

	return 0;
}

static void __exit crypto_user_exit(void)
{
	netlink_kernel_release(crypto_nlsk);
}

module_init(crypto_user_init);
module_exit(crypto_user_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
MODULE_DESCRIPTION("Crypto userspace configuration API");
MODULE_ALIAS("net-pf-16-proto-21");
Commit	Line	Data
a38f7907 SK	1	/*
	2	* Crypto user configuration API.
	3	*
	4	* Copyright (C) 2011 secunet Security Networks AG
	5	* Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify it
	8	* under the terms and conditions of the GNU General Public License,
	9	* version 2, as published by the Free Software Foundation.
	10	*
	11	* This program is distributed in the hope it will be useful, but WITHOUT
	12	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	13	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	14	* more details.
	15	*
	16	* You should have received a copy of the GNU General Public License along with
	17	* this program; if not, write to the Free Software Foundation, Inc.,
	18	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	19	*/
	20
	21	#include <linux/module.h>
	22	#include <linux/crypto.h>
	23	#include <linux/cryptouser.h>
1e122994	24	#include <linux/sched.h>
a38f7907 SK	25	#include <net/netlink.h>
	26	#include <linux/security.h>
	27	#include <net/net_namespace.h>
1e122994 SK	28	#include <crypto/internal/aead.h>
	29	#include <crypto/internal/skcipher.h>
	30
a38f7907 SK	31	#include "internal.h"
a38f7907 SK	32
8fd61d34 MK	33	#define null_terminated(x) (strnlen(x, sizeof(x)) < sizeof(x))
8fd61d34 MK	34
66ce0b0f	35	static DEFINE_MUTEX(crypto_cfg_mutex);
a38f7907 SK	36
	37	/* The crypto netlink socket */
	38	static struct sock *crypto_nlsk;
	39
	40	struct crypto_dump_info {
	41	struct sk_buff *in_skb;
	42	struct sk_buff *out_skb;
	43	u32 nlmsg_seq;
	44	u16 nlmsg_flags;
	45	};
	46
	47	static struct crypto_alg crypto_alg_match(struct crypto_user_alg p, int exact)
	48	{
a38f7907 SK	49	struct crypto_alg q, alg = NULL;
	50
	51	down_read(&crypto_alg_sem);
	52
a38f7907	53	list_for_each_entry(q, &crypto_alg_list, cra_list) {
e6ea64ec	54	int match = 0;
a38f7907 SK	55
	56	if ((q->cra_flags ^ p->cru_type) & p->cru_mask)
	57	continue;
	58
	59	if (strlen(p->cru_driver_name))
	60	match = !strcmp(q->cra_driver_name,
	61	p->cru_driver_name);
	62	else if (!exact)
	63	match = !strcmp(q->cra_name, p->cru_name);
	64
016baaa1 HX	65	if (!match)
	66	continue;
	67
	68	if (unlikely(!crypto_mod_get(q)))
	69	continue;
	70
	71	alg = q;
	72	break;
a38f7907 SK	73	}
	74
	75	up_read(&crypto_alg_sem);
	76
	77	return alg;
	78	}
	79
07a5fa4a SK	80	static int crypto_report_cipher(struct sk_buff skb, struct crypto_alg alg)
	81	{
	82	struct crypto_report_cipher rcipher;
	83
9a5467bf	84	strncpy(rcipher.type, "cipher", sizeof(rcipher.type));
07a5fa4a SK	85
	86	rcipher.blocksize = alg->cra_blocksize;
	87	rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
	88	rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
	89
6662df33 DM	90	if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
	91	sizeof(struct crypto_report_cipher), &rcipher))
	92	goto nla_put_failure;
07a5fa4a SK	93	return 0;
	94
	95	nla_put_failure:
	96	return -EMSGSIZE;
	97	}
	98
540b97c1 SK	99	static int crypto_report_comp(struct sk_buff skb, struct crypto_alg alg)
	100	{
	101	struct crypto_report_comp rcomp;
	102
9a5467bf	103	strncpy(rcomp.type, "compression", sizeof(rcomp.type));
6662df33 DM	104	if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
	105	sizeof(struct crypto_report_comp), &rcomp))
	106	goto nla_put_failure;
540b97c1 SK	107	return 0;
	108
	109	nla_put_failure:
	110	return -EMSGSIZE;
	111	}
	112
a38f7907 SK	113	static int crypto_report_one(struct crypto_alg *alg,
	114	struct crypto_user_alg ualg, struct sk_buff skb)
	115	{
9a5467bf MK	116	strncpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
	117	strncpy(ualg->cru_driver_name, alg->cra_driver_name,
	118	sizeof(ualg->cru_driver_name));
	119	strncpy(ualg->cru_module_name, module_name(alg->cra_module),
	120	sizeof(ualg->cru_module_name));
	121
	122	ualg->cru_type = 0;
	123	ualg->cru_mask = 0;
a38f7907 SK	124	ualg->cru_flags = alg->cra_flags;
	125	ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);
	126
6662df33 DM	127	if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
6662df33 DM	128	goto nla_put_failure;
6c5a86f5 SK	129	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
	130	struct crypto_report_larval rl;
	131
9a5467bf	132	strncpy(rl.type, "larval", sizeof(rl.type));
6662df33 DM	133	if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL,
	134	sizeof(struct crypto_report_larval), &rl))
	135	goto nla_put_failure;
6c5a86f5 SK	136	goto out;
	137	}
	138
b6aa63c0 SK	139	if (alg->cra_type && alg->cra_type->report) {
	140	if (alg->cra_type->report(skb, alg))
	141	goto nla_put_failure;
07a5fa4a SK	142
	143	goto out;
	144	}
	145
	146	switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_LARVAL)) {
	147	case CRYPTO_ALG_TYPE_CIPHER:
	148	if (crypto_report_cipher(skb, alg))
	149	goto nla_put_failure;
	150
540b97c1 SK	151	break;
	152	case CRYPTO_ALG_TYPE_COMPRESS:
	153	if (crypto_report_comp(skb, alg))
	154	goto nla_put_failure;
	155
07a5fa4a	156	break;
b6aa63c0 SK	157	}
b6aa63c0 SK	158
6c5a86f5	159	out:
a38f7907 SK	160	return 0;
	161
	162	nla_put_failure:
	163	return -EMSGSIZE;
	164	}
	165
	166	static int crypto_report_alg(struct crypto_alg *alg,
	167	struct crypto_dump_info *info)
	168	{
	169	struct sk_buff *in_skb = info->in_skb;
	170	struct sk_buff *skb = info->out_skb;
	171	struct nlmsghdr *nlh;
	172	struct crypto_user_alg *ualg;
	173	int err = 0;
	174
15e47304	175	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
a38f7907 SK	176	CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
	177	if (!nlh) {
	178	err = -EMSGSIZE;
	179	goto out;
	180	}
	181
	182	ualg = nlmsg_data(nlh);
	183
	184	err = crypto_report_one(alg, ualg, skb);
	185	if (err) {
	186	nlmsg_cancel(skb, nlh);
	187	goto out;
	188	}
	189
	190	nlmsg_end(skb, nlh);
	191
	192	out:
	193	return err;
	194	}
	195
	196	static int crypto_report(struct sk_buff in_skb, struct nlmsghdr in_nlh,
	197	struct nlattr **attrs)
	198	{
	199	struct crypto_user_alg *p = nlmsg_data(in_nlh);
	200	struct crypto_alg *alg;
	201	struct sk_buff *skb;
	202	struct crypto_dump_info info;
	203	int err;
	204
8fd61d34 MK	205	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	206	return -EINVAL;
	207
5d4a5e77	208	alg = crypto_alg_match(p, 0);
a38f7907 SK	209	if (!alg)
	210	return -ENOENT;
	211
016baaa1	212	err = -ENOMEM;
a38f7907 SK	213	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
a38f7907 SK	214	if (!skb)
016baaa1	215	goto drop_alg;
a38f7907 SK	216
	217	info.in_skb = in_skb;
	218	info.out_skb = skb;
	219	info.nlmsg_seq = in_nlh->nlmsg_seq;
	220	info.nlmsg_flags = 0;
	221
	222	err = crypto_report_alg(alg, &info);
016baaa1 HX	223
	224	drop_alg:
	225	crypto_mod_put(alg);
	226
a38f7907 SK	227	if (err)
	228	return err;
	229
15e47304	230	return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
a38f7907 SK	231	}
	232
	233	static int crypto_dump_report(struct sk_buff skb, struct netlink_callback cb)
	234	{
	235	struct crypto_alg *alg;
	236	struct crypto_dump_info info;
	237	int err;
	238
	239	if (cb->args[0])
	240	goto out;
	241
	242	cb->args[0] = 1;
	243
	244	info.in_skb = cb->skb;
	245	info.out_skb = skb;
	246	info.nlmsg_seq = cb->nlh->nlmsg_seq;
	247	info.nlmsg_flags = NLM_F_MULTI;
	248
	249	list_for_each_entry(alg, &crypto_alg_list, cra_list) {
	250	err = crypto_report_alg(alg, &info);
	251	if (err)
	252	goto out_err;
	253	}
	254
	255	out:
	256	return skb->len;
	257	out_err:
	258	return err;
	259	}
	260
	261	static int crypto_dump_report_done(struct netlink_callback *cb)
	262	{
	263	return 0;
	264	}
	265
	266	static int crypto_update_alg(struct sk_buff skb, struct nlmsghdr nlh,
	267	struct nlattr **attrs)
	268	{
	269	struct crypto_alg *alg;
	270	struct crypto_user_alg *p = nlmsg_data(nlh);
	271	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	272	LIST_HEAD(list);
	273
639b4ac6	274	if (!netlink_capable(skb, CAP_NET_ADMIN))
c568398a MCO	275	return -EPERM;
c568398a MCO	276
8fd61d34 MK	277	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	278	return -EINVAL;
	279
a38f7907 SK	280	if (priority && !strlen(p->cru_driver_name))
	281	return -EINVAL;
	282
	283	alg = crypto_alg_match(p, 1);
	284	if (!alg)
	285	return -ENOENT;
	286
	287	down_write(&crypto_alg_sem);
	288
	289	crypto_remove_spawns(alg, &list, NULL);
	290
	291	if (priority)
	292	alg->cra_priority = nla_get_u32(priority);
	293
	294	up_write(&crypto_alg_sem);
	295
016baaa1	296	crypto_mod_put(alg);
a38f7907 SK	297	crypto_remove_final(&list);
	298
	299	return 0;
	300	}
	301
	302	static int crypto_del_alg(struct sk_buff skb, struct nlmsghdr nlh,
	303	struct nlattr **attrs)
	304	{
	305	struct crypto_alg *alg;
	306	struct crypto_user_alg *p = nlmsg_data(nlh);
016baaa1	307	int err;
a38f7907	308
639b4ac6	309	if (!netlink_capable(skb, CAP_NET_ADMIN))
c568398a MCO	310	return -EPERM;
c568398a MCO	311
8fd61d34 MK	312	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	313	return -EINVAL;
	314
a38f7907 SK	315	alg = crypto_alg_match(p, 1);
	316	if (!alg)
	317	return -ENOENT;
	318
	319	/* We can not unregister core algorithms such as aes-generic.
	320	* We would loose the reference in the crypto_alg_list to this algorithm
	321	* if we try to unregister. Unregistering such an algorithm without
	322	* removing the module is not possible, so we restrict to crypto
	323	* instances that are build from templates. */
016baaa1	324	err = -EINVAL;
a38f7907	325	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
016baaa1	326	goto drop_alg;
a38f7907	327
016baaa1 HX	328	err = -EBUSY;
	329	if (atomic_read(&alg->cra_refcnt) > 2)
	330	goto drop_alg;
a38f7907	331
016baaa1 HX	332	err = crypto_unregister_instance((struct crypto_instance *)alg);
	333
	334	drop_alg:
	335	crypto_mod_put(alg);
	336	return err;
a38f7907 SK	337	}
a38f7907 SK	338
1e122994 SK	339	static struct crypto_alg crypto_user_skcipher_alg(const char name, u32 type,
	340	u32 mask)
	341	{
	342	int err;
	343	struct crypto_alg *alg;
	344
	345	type = crypto_skcipher_type(type);
	346	mask = crypto_skcipher_mask(mask);
	347
	348	for (;;) {
	349	alg = crypto_lookup_skcipher(name, type, mask);
	350	if (!IS_ERR(alg))
	351	return alg;
	352
	353	err = PTR_ERR(alg);
	354	if (err != -EAGAIN)
	355	break;
	356	if (signal_pending(current)) {
	357	err = -EINTR;
	358	break;
	359	}
	360	}
	361
	362	return ERR_PTR(err);
	363	}
	364
	365	static struct crypto_alg crypto_user_aead_alg(const char name, u32 type,
	366	u32 mask)
	367	{
	368	int err;
	369	struct crypto_alg *alg;
	370
	371	type &= ~(CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_GENIV);
	372	type \|= CRYPTO_ALG_TYPE_AEAD;
	373	mask &= ~(CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_GENIV);
	374	mask \|= CRYPTO_ALG_TYPE_MASK;
	375
	376	for (;;) {
	377	alg = crypto_lookup_aead(name, type, mask);
	378	if (!IS_ERR(alg))
	379	return alg;
	380
	381	err = PTR_ERR(alg);
	382	if (err != -EAGAIN)
	383	break;
	384	if (signal_pending(current)) {
	385	err = -EINTR;
	386	break;
	387	}
	388	}
	389
	390	return ERR_PTR(err);
	391	}
	392
a38f7907 SK	393	static int crypto_add_alg(struct sk_buff skb, struct nlmsghdr nlh,
	394	struct nlattr **attrs)
	395	{
0cfdec7a	396	int exact = 0;
a38f7907 SK	397	const char *name;
	398	struct crypto_alg *alg;
	399	struct crypto_user_alg *p = nlmsg_data(nlh);
	400	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	401
639b4ac6	402	if (!netlink_capable(skb, CAP_NET_ADMIN))
c568398a MCO	403	return -EPERM;
c568398a MCO	404
8fd61d34 MK	405	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	406	return -EINVAL;
	407
a38f7907 SK	408	if (strlen(p->cru_driver_name))
	409	exact = 1;
	410
	411	if (priority && !exact)
	412	return -EINVAL;
	413
	414	alg = crypto_alg_match(p, exact);
016baaa1 HX	415	if (alg) {
016baaa1 HX	416	crypto_mod_put(alg);
a38f7907	417	return -EEXIST;
016baaa1	418	}
a38f7907 SK	419
	420	if (strlen(p->cru_driver_name))
	421	name = p->cru_driver_name;
	422	else
	423	name = p->cru_name;
	424
1e122994 SK	425	switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) {
	426	case CRYPTO_ALG_TYPE_AEAD:
	427	alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask);
	428	break;
	429	case CRYPTO_ALG_TYPE_GIVCIPHER:
	430	case CRYPTO_ALG_TYPE_BLKCIPHER:
	431	case CRYPTO_ALG_TYPE_ABLKCIPHER:
	432	alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask);
	433	break;
	434	default:
	435	alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
	436	}
	437
a38f7907 SK	438	if (IS_ERR(alg))
	439	return PTR_ERR(alg);
	440
	441	down_write(&crypto_alg_sem);
	442
	443	if (priority)
	444	alg->cra_priority = nla_get_u32(priority);
	445
	446	up_write(&crypto_alg_sem);
	447
	448	crypto_mod_put(alg);
	449
	450	return 0;
	451	}
	452
	453	#define MSGSIZE(type) sizeof(struct type)
	454
	455	static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
	456	[CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	457	[CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	458	[CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	459	[CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	460	};
	461
	462	static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
	463	[CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32},
	464	};
	465
	466	#undef MSGSIZE
	467
a84fb791	468	static const struct crypto_link {
a38f7907 SK	469	int (doit)(struct sk_buff , struct nlmsghdr , struct nlattr *);
	470	int (dump)(struct sk_buff , struct netlink_callback *);
	471	int (done)(struct netlink_callback );
	472	} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
	473	[CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
	474	[CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
	475	[CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
	476	[CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report,
	477	.dump = crypto_dump_report,
	478	.done = crypto_dump_report_done},
	479	};
	480
	481	static int crypto_user_rcv_msg(struct sk_buff skb, struct nlmsghdr nlh)
	482	{
	483	struct nlattr *attrs[CRYPTOCFGA_MAX+1];
a84fb791	484	const struct crypto_link *link;
a38f7907 SK	485	int type, err;
	486
	487	type = nlh->nlmsg_type;
	488	if (type > CRYPTO_MSG_MAX)
	489	return -EINVAL;
	490
	491	type -= CRYPTO_MSG_BASE;
	492	link = &crypto_dispatch[type];
	493
a38f7907 SK	494	if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
a38f7907 SK	495	(nlh->nlmsg_flags & NLM_F_DUMP))) {
5219a534 SK	496	struct crypto_alg *alg;
	497	u16 dump_alloc = 0;
	498
a38f7907 SK	499	if (link->dump == NULL)
a38f7907 SK	500	return -EINVAL;
5219a534 SK	501
	502	list_for_each_entry(alg, &crypto_alg_list, cra_list)
	503	dump_alloc += CRYPTO_REPORT_MAXSIZE;
	504
80d326fa PNA	505	{
	506	struct netlink_dump_control c = {
	507	.dump = link->dump,
	508	.done = link->done,
5219a534	509	.min_dump_alloc = dump_alloc,
80d326fa PNA	510	};
	511	return netlink_dump_start(crypto_nlsk, skb, nlh, &c);
	512	}
a38f7907 SK	513	}
	514
	515	err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
	516	crypto_policy);
	517	if (err < 0)
	518	return err;
	519
	520	if (link->doit == NULL)
	521	return -EINVAL;
	522
	523	return link->doit(skb, nlh, attrs);
	524	}
	525
	526	static void crypto_netlink_rcv(struct sk_buff *skb)
	527	{
	528	mutex_lock(&crypto_cfg_mutex);
	529	netlink_rcv_skb(skb, &crypto_user_rcv_msg);
	530	mutex_unlock(&crypto_cfg_mutex);
	531	}
	532
	533	static int __init crypto_user_init(void)
	534	{
a31f2d17 PNA	535	struct netlink_kernel_cfg cfg = {
	536	.input = crypto_netlink_rcv,
	537	};
	538
9f00d977	539	crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg);
a38f7907 SK	540	if (!crypto_nlsk)
	541	return -ENOMEM;
	542
	543	return 0;
	544	}
	545
	546	static void __exit crypto_user_exit(void)
	547	{
	548	netlink_kernel_release(crypto_nlsk);
	549	}
	550
	551	module_init(crypto_user_init);
	552	module_exit(crypto_user_exit);
	553	MODULE_LICENSE("GPL");
	554	MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
	555	MODULE_DESCRIPTION("Crypto userspace configuration API");
476c7fe2	556	MODULE_ALIAS("net-pf-16-proto-21");