[linux.git] / crypto / crypto_user_base.c

/*
 * Crypto user configuration API.
 *
 * Copyright (C) 2011 secunet Security Networks AG
 * Copyright (C) 2011 Steffen Klassert <[email protected]>
 *
 * 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/skcipher.h>
#include <crypto/internal/rng.h>
#include <crypto/akcipher.h>
#include <crypto/kpp.h>
#include <crypto/internal/cryptouser.h>

#include "internal.h"

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

static DEFINE_MUTEX(crypto_cfg_mutex);

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

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

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;

	memset(&rcipher, 0, sizeof(rcipher));

	strscpy(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;

	return nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
		       sizeof(rcipher), &rcipher);
}

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

	memset(&rcomp, 0, sizeof(rcomp));

	strscpy(rcomp.type, "compression", sizeof(rcomp.type));

	return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS, sizeof(rcomp), &rcomp);
}

static int crypto_report_one(struct crypto_alg *alg,
			     struct crypto_user_alg *ualg, struct sk_buff *skb)
{
	memset(ualg, 0, sizeof(*ualg));

	strscpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
	strscpy(ualg->cru_driver_name, alg->cra_driver_name,
		sizeof(ualg->cru_driver_name));
	strscpy(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 = refcount_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;

		memset(&rl, 0, sizeof(rl));
		strscpy(rl.type, "larval", sizeof(rl.type));
		if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL, sizeof(rl), &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_KERNEL);
	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)
{
	const size_t start_pos = cb->args[0];
	size_t pos = 0;
	struct crypto_dump_info info;
	struct crypto_alg *alg;
	int res;

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

	down_read(&crypto_alg_sem);
	list_for_each_entry(alg, &crypto_alg_list, cra_list) {
		if (pos >= start_pos) {
			res = crypto_report_alg(alg, &info);
			if (res == -EMSGSIZE)
				break;
			if (res)
				goto out;
		}
		pos++;
	}
	cb->args[0] = pos;
	res = skb->len;
out:
	up_read(&crypto_alg_sem);
	return res;
}

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 (refcount_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 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;

	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;
}

static int crypto_del_rng(struct sk_buff *skb, struct nlmsghdr *nlh,
			  struct nlattr **attrs)
{
	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;
	return crypto_del_default_rng();
}

#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),
	[CRYPTO_MSG_DELRNG	- CRYPTO_MSG_BASE] = 0,
	[CRYPTO_MSG_GETSTAT	- 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},
	[CRYPTO_MSG_DELRNG	- CRYPTO_MSG_BASE] = { .doit = crypto_del_rng },
	[CRYPTO_MSG_GETSTAT	- CRYPTO_MSG_BASE] = { .doit = crypto_reportstat},
};

static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
			       struct netlink_ext_ack *extack)
{
	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;
		unsigned long dump_alloc = 0;

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

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

		{
			struct netlink_dump_control c = {
				.dump = link->dump,
				.done = link->done,
				.min_dump_alloc = min(dump_alloc, 65535UL),
			};
			err = netlink_dump_start(crypto_nlsk, skb, nlh, &c);
		}

		return err;
	}

	err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
			  crypto_policy, extack);
	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 <[email protected]>");
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 <[email protected]>
	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	28	#include <crypto/internal/skcipher.h>
9aa867e4	29	#include <crypto/internal/rng.h>
3c339ab8	30	#include <crypto/akcipher.h>
4e5f2c40	31	#include <crypto/kpp.h>
cac5818c	32	#include <crypto/internal/cryptouser.h>
1e122994	33
a38f7907 SK	34	#include "internal.h"
a38f7907 SK	35
8fd61d34 MK	36	#define null_terminated(x) (strnlen(x, sizeof(x)) < sizeof(x))
8fd61d34 MK	37
66ce0b0f	38	static DEFINE_MUTEX(crypto_cfg_mutex);
a38f7907 SK	39
a38f7907 SK	40	/* The crypto netlink socket */
cac5818c	41	struct sock *crypto_nlsk;
a38f7907 SK	42
	43	struct crypto_dump_info {
	44	struct sk_buff *in_skb;
	45	struct sk_buff *out_skb;
	46	u32 nlmsg_seq;
	47	u16 nlmsg_flags;
	48	};
	49
cac5818c	50	struct crypto_alg crypto_alg_match(struct crypto_user_alg p, int exact)
a38f7907	51	{
a38f7907 SK	52	struct crypto_alg q, alg = NULL;
	53
	54	down_read(&crypto_alg_sem);
	55
a38f7907	56	list_for_each_entry(q, &crypto_alg_list, cra_list) {
e6ea64ec	57	int match = 0;
a38f7907 SK	58
	59	if ((q->cra_flags ^ p->cru_type) & p->cru_mask)
	60	continue;
	61
	62	if (strlen(p->cru_driver_name))
	63	match = !strcmp(q->cra_driver_name,
	64	p->cru_driver_name);
	65	else if (!exact)
	66	match = !strcmp(q->cra_name, p->cru_name);
	67
016baaa1 HX	68	if (!match)
	69	continue;
	70
	71	if (unlikely(!crypto_mod_get(q)))
	72	continue;
	73
	74	alg = q;
	75	break;
a38f7907 SK	76	}
	77
	78	up_read(&crypto_alg_sem);
	79
	80	return alg;
	81	}
	82
07a5fa4a SK	83	static int crypto_report_cipher(struct sk_buff skb, struct crypto_alg alg)
	84	{
	85	struct crypto_report_cipher rcipher;
	86
37db69e0 EB	87	memset(&rcipher, 0, sizeof(rcipher));
	88
	89	strscpy(rcipher.type, "cipher", sizeof(rcipher.type));
07a5fa4a SK	90
	91	rcipher.blocksize = alg->cra_blocksize;
	92	rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
	93	rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
	94
37db69e0 EB	95	return nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
37db69e0 EB	96	sizeof(rcipher), &rcipher);
07a5fa4a SK	97	}
07a5fa4a SK	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
37db69e0 EB	103	memset(&rcomp, 0, sizeof(rcomp));
	104
	105	strscpy(rcomp.type, "compression", sizeof(rcomp.type));
540b97c1	106
37db69e0	107	return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS, sizeof(rcomp), &rcomp);
540b97c1 SK	108	}
540b97c1 SK	109
a38f7907 SK	110	static int crypto_report_one(struct crypto_alg *alg,
	111	struct crypto_user_alg ualg, struct sk_buff skb)
	112	{
37db69e0 EB	113	memset(ualg, 0, sizeof(*ualg));
	114
	115	strscpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
	116	strscpy(ualg->cru_driver_name, alg->cra_driver_name,
9a5467bf	117	sizeof(ualg->cru_driver_name));
37db69e0	118	strscpy(ualg->cru_module_name, module_name(alg->cra_module),
9a5467bf MK	119	sizeof(ualg->cru_module_name));
	120
	121	ualg->cru_type = 0;
	122	ualg->cru_mask = 0;
a38f7907	123	ualg->cru_flags = alg->cra_flags;
ce8614a3	124	ualg->cru_refcnt = refcount_read(&alg->cra_refcnt);
a38f7907	125
6662df33 DM	126	if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
6662df33 DM	127	goto nla_put_failure;
6c5a86f5 SK	128	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
	129	struct crypto_report_larval rl;
	130
37db69e0 EB	131	memset(&rl, 0, sizeof(rl));
	132	strscpy(rl.type, "larval", sizeof(rl.type));
	133	if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL, sizeof(rl), &rl))
6662df33	134	goto nla_put_failure;
6c5a86f5 SK	135	goto out;
	136	}
	137
b6aa63c0 SK	138	if (alg->cra_type && alg->cra_type->report) {
	139	if (alg->cra_type->report(skb, alg))
	140	goto nla_put_failure;
07a5fa4a SK	141
	142	goto out;
	143	}
	144
	145	switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_LARVAL)) {
	146	case CRYPTO_ALG_TYPE_CIPHER:
	147	if (crypto_report_cipher(skb, alg))
	148	goto nla_put_failure;
	149
540b97c1 SK	150	break;
	151	case CRYPTO_ALG_TYPE_COMPRESS:
	152	if (crypto_report_comp(skb, alg))
	153	goto nla_put_failure;
	154
07a5fa4a	155	break;
b6aa63c0 SK	156	}
b6aa63c0 SK	157
6c5a86f5	158	out:
a38f7907 SK	159	return 0;
	160
	161	nla_put_failure:
	162	return -EMSGSIZE;
	163	}
	164
	165	static int crypto_report_alg(struct crypto_alg *alg,
	166	struct crypto_dump_info *info)
	167	{
	168	struct sk_buff *in_skb = info->in_skb;
	169	struct sk_buff *skb = info->out_skb;
	170	struct nlmsghdr *nlh;
	171	struct crypto_user_alg *ualg;
	172	int err = 0;
	173
15e47304	174	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
a38f7907 SK	175	CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
	176	if (!nlh) {
	177	err = -EMSGSIZE;
	178	goto out;
	179	}
	180
	181	ualg = nlmsg_data(nlh);
	182
	183	err = crypto_report_one(alg, ualg, skb);
	184	if (err) {
	185	nlmsg_cancel(skb, nlh);
	186	goto out;
	187	}
	188
	189	nlmsg_end(skb, nlh);
	190
	191	out:
	192	return err;
	193	}
	194
	195	static int crypto_report(struct sk_buff in_skb, struct nlmsghdr in_nlh,
	196	struct nlattr **attrs)
	197	{
	198	struct crypto_user_alg *p = nlmsg_data(in_nlh);
	199	struct crypto_alg *alg;
	200	struct sk_buff *skb;
	201	struct crypto_dump_info info;
	202	int err;
	203
8fd61d34 MK	204	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	205	return -EINVAL;
	206
5d4a5e77	207	alg = crypto_alg_match(p, 0);
a38f7907 SK	208	if (!alg)
	209	return -ENOENT;
	210
016baaa1	211	err = -ENOMEM;
9a69b7ae	212	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
a38f7907	213	if (!skb)
016baaa1	214	goto drop_alg;
a38f7907 SK	215
	216	info.in_skb = in_skb;
	217	info.out_skb = skb;
	218	info.nlmsg_seq = in_nlh->nlmsg_seq;
	219	info.nlmsg_flags = 0;
	220
	221	err = crypto_report_alg(alg, &info);
016baaa1 HX	222
	223	drop_alg:
	224	crypto_mod_put(alg);
	225
a38f7907 SK	226	if (err)
	227	return err;
	228
15e47304	229	return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
a38f7907 SK	230	}
	231
	232	static int crypto_dump_report(struct sk_buff skb, struct netlink_callback cb)
	233	{
0ac6b8fb EB	234	const size_t start_pos = cb->args[0];
0ac6b8fb EB	235	size_t pos = 0;
a38f7907	236	struct crypto_dump_info info;
0ac6b8fb EB	237	struct crypto_alg *alg;
0ac6b8fb EB	238	int res;
a38f7907 SK	239
	240	info.in_skb = cb->skb;
	241	info.out_skb = skb;
	242	info.nlmsg_seq = cb->nlh->nlmsg_seq;
	243	info.nlmsg_flags = NLM_F_MULTI;
	244
0ac6b8fb	245	down_read(&crypto_alg_sem);
a38f7907	246	list_for_each_entry(alg, &crypto_alg_list, cra_list) {
0ac6b8fb EB	247	if (pos >= start_pos) {
	248	res = crypto_report_alg(alg, &info);
	249	if (res == -EMSGSIZE)
	250	break;
	251	if (res)
	252	goto out;
	253	}
	254	pos++;
a38f7907	255	}
0ac6b8fb EB	256	cb->args[0] = pos;
0ac6b8fb EB	257	res = skb->len;
a38f7907	258	out:
0ac6b8fb EB	259	up_read(&crypto_alg_sem);
0ac6b8fb EB	260	return res;
a38f7907 SK	261	}
	262
	263	static int crypto_dump_report_done(struct netlink_callback *cb)
	264	{
	265	return 0;
	266	}
	267
	268	static int crypto_update_alg(struct sk_buff skb, struct nlmsghdr nlh,
	269	struct nlattr **attrs)
	270	{
	271	struct crypto_alg *alg;
	272	struct crypto_user_alg *p = nlmsg_data(nlh);
	273	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	274	LIST_HEAD(list);
	275
639b4ac6	276	if (!netlink_capable(skb, CAP_NET_ADMIN))
c568398a MCO	277	return -EPERM;
c568398a MCO	278
8fd61d34 MK	279	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	280	return -EINVAL;
	281
a38f7907 SK	282	if (priority && !strlen(p->cru_driver_name))
	283	return -EINVAL;
	284
	285	alg = crypto_alg_match(p, 1);
	286	if (!alg)
	287	return -ENOENT;
	288
	289	down_write(&crypto_alg_sem);
	290
	291	crypto_remove_spawns(alg, &list, NULL);
	292
	293	if (priority)
	294	alg->cra_priority = nla_get_u32(priority);
	295
	296	up_write(&crypto_alg_sem);
	297
016baaa1	298	crypto_mod_put(alg);
a38f7907 SK	299	crypto_remove_final(&list);
	300
	301	return 0;
	302	}
	303
	304	static int crypto_del_alg(struct sk_buff skb, struct nlmsghdr nlh,
	305	struct nlattr **attrs)
	306	{
	307	struct crypto_alg *alg;
	308	struct crypto_user_alg *p = nlmsg_data(nlh);
016baaa1	309	int err;
a38f7907	310
639b4ac6	311	if (!netlink_capable(skb, CAP_NET_ADMIN))
c568398a MCO	312	return -EPERM;
c568398a MCO	313
8fd61d34 MK	314	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	315	return -EINVAL;
	316
a38f7907 SK	317	alg = crypto_alg_match(p, 1);
	318	if (!alg)
	319	return -ENOENT;
	320
	321	/* We can not unregister core algorithms such as aes-generic.
	322	* We would loose the reference in the crypto_alg_list to this algorithm
	323	* if we try to unregister. Unregistering such an algorithm without
	324	* removing the module is not possible, so we restrict to crypto
	325	* instances that are build from templates. */
016baaa1	326	err = -EINVAL;
a38f7907	327	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
016baaa1	328	goto drop_alg;
a38f7907	329
016baaa1	330	err = -EBUSY;
ce8614a3	331	if (refcount_read(&alg->cra_refcnt) > 2)
016baaa1	332	goto drop_alg;
a38f7907	333
016baaa1 HX	334	err = crypto_unregister_instance((struct crypto_instance *)alg);
	335
	336	drop_alg:
	337	crypto_mod_put(alg);
	338	return err;
a38f7907 SK	339	}
	340
	341	static int crypto_add_alg(struct sk_buff skb, struct nlmsghdr nlh,
	342	struct nlattr **attrs)
	343	{
0cfdec7a	344	int exact = 0;
a38f7907 SK	345	const char *name;
	346	struct crypto_alg *alg;
	347	struct crypto_user_alg *p = nlmsg_data(nlh);
	348	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	349
639b4ac6	350	if (!netlink_capable(skb, CAP_NET_ADMIN))
c568398a MCO	351	return -EPERM;
c568398a MCO	352
8fd61d34 MK	353	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	354	return -EINVAL;
	355
a38f7907 SK	356	if (strlen(p->cru_driver_name))
	357	exact = 1;
	358
	359	if (priority && !exact)
	360	return -EINVAL;
	361
	362	alg = crypto_alg_match(p, exact);
016baaa1 HX	363	if (alg) {
016baaa1 HX	364	crypto_mod_put(alg);
a38f7907	365	return -EEXIST;
016baaa1	366	}
a38f7907 SK	367
	368	if (strlen(p->cru_driver_name))
	369	name = p->cru_driver_name;
	370	else
	371	name = p->cru_name;
	372
6cf80a29	373	alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
a38f7907 SK	374	if (IS_ERR(alg))
	375	return PTR_ERR(alg);
	376
	377	down_write(&crypto_alg_sem);
	378
	379	if (priority)
	380	alg->cra_priority = nla_get_u32(priority);
	381
	382	up_write(&crypto_alg_sem);
	383
	384	crypto_mod_put(alg);
	385
	386	return 0;
	387	}
	388
9aa867e4 HX	389	static int crypto_del_rng(struct sk_buff skb, struct nlmsghdr nlh,
	390	struct nlattr **attrs)
	391	{
	392	if (!netlink_capable(skb, CAP_NET_ADMIN))
	393	return -EPERM;
	394	return crypto_del_default_rng();
	395	}
	396
a38f7907 SK	397	#define MSGSIZE(type) sizeof(struct type)
	398
	399	static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
	400	[CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	401	[CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	402	[CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
055ddaac	403	[CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
9aa867e4	404	[CRYPTO_MSG_DELRNG - CRYPTO_MSG_BASE] = 0,
cac5818c	405	[CRYPTO_MSG_GETSTAT - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
a38f7907 SK	406	};
	407
	408	static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
	409	[CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32},
	410	};
	411
	412	#undef MSGSIZE
	413
a84fb791	414	static const struct crypto_link {
a38f7907 SK	415	int (doit)(struct sk_buff , struct nlmsghdr , struct nlattr *);
	416	int (dump)(struct sk_buff , struct netlink_callback *);
	417	int (done)(struct netlink_callback );
	418	} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
	419	[CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
	420	[CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
	421	[CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
	422	[CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report,
	423	.dump = crypto_dump_report,
	424	.done = crypto_dump_report_done},
9aa867e4	425	[CRYPTO_MSG_DELRNG - CRYPTO_MSG_BASE] = { .doit = crypto_del_rng },
0c99c2a0	426	[CRYPTO_MSG_GETSTAT - CRYPTO_MSG_BASE] = { .doit = crypto_reportstat},
a38f7907 SK	427	};
a38f7907 SK	428
2d4bc933 JB	429	static int crypto_user_rcv_msg(struct sk_buff skb, struct nlmsghdr nlh,
2d4bc933 JB	430	struct netlink_ext_ack *extack)
a38f7907 SK	431	{
a38f7907 SK	432	struct nlattr *attrs[CRYPTOCFGA_MAX+1];
a84fb791	433	const struct crypto_link *link;
a38f7907 SK	434	int type, err;
	435
	436	type = nlh->nlmsg_type;
	437	if (type > CRYPTO_MSG_MAX)
	438	return -EINVAL;
	439
	440	type -= CRYPTO_MSG_BASE;
	441	link = &crypto_dispatch[type];
	442
a38f7907 SK	443	if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
a38f7907 SK	444	(nlh->nlmsg_flags & NLM_F_DUMP))) {
5219a534	445	struct crypto_alg *alg;
0ac6b8fb	446	unsigned long dump_alloc = 0;
5219a534	447
a38f7907 SK	448	if (link->dump == NULL)
a38f7907 SK	449	return -EINVAL;
5219a534	450
63e41ebc	451	down_read(&crypto_alg_sem);
5219a534 SK	452	list_for_each_entry(alg, &crypto_alg_list, cra_list)
5219a534 SK	453	dump_alloc += CRYPTO_REPORT_MAXSIZE;
0ac6b8fb	454	up_read(&crypto_alg_sem);
5219a534	455
80d326fa PNA	456	{
	457	struct netlink_dump_control c = {
	458	.dump = link->dump,
	459	.done = link->done,
0ac6b8fb	460	.min_dump_alloc = min(dump_alloc, 65535UL),
80d326fa	461	};
63e41ebc	462	err = netlink_dump_start(crypto_nlsk, skb, nlh, &c);
80d326fa	463	}
63e41ebc MK	464
63e41ebc MK	465	return err;
a38f7907 SK	466	}
a38f7907 SK	467
fd2efd93	468	err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
fe52145f	469	crypto_policy, extack);
fd2efd93 HX	470	if (err < 0)
fd2efd93 HX	471	return err;
a38f7907 SK	472
	473	if (link->doit == NULL)
	474	return -EINVAL;
	475
	476	return link->doit(skb, nlh, attrs);
	477	}
	478
	479	static void crypto_netlink_rcv(struct sk_buff *skb)
	480	{
	481	mutex_lock(&crypto_cfg_mutex);
	482	netlink_rcv_skb(skb, &crypto_user_rcv_msg);
	483	mutex_unlock(&crypto_cfg_mutex);
	484	}
	485
	486	static int __init crypto_user_init(void)
	487	{
a31f2d17 PNA	488	struct netlink_kernel_cfg cfg = {
	489	.input = crypto_netlink_rcv,
	490	};
	491
9f00d977	492	crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg);
a38f7907 SK	493	if (!crypto_nlsk)
	494	return -ENOMEM;
	495
	496	return 0;
	497	}
	498
	499	static void __exit crypto_user_exit(void)
	500	{
	501	netlink_kernel_release(crypto_nlsk);
	502	}
	503
	504	module_init(crypto_user_init);
	505	module_exit(crypto_user_exit);
	506	MODULE_LICENSE("GPL");
	507	MODULE_AUTHOR("Steffen Klassert <[email protected]>");
	508	MODULE_DESCRIPTION("Crypto userspace configuration API");
476c7fe2	509	MODULE_ALIAS("net-pf-16-proto-21");