[linux.git] / crypto / crypto_user.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/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) {
			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;

	if (!p->cru_driver_name[0])
		return -EINVAL;

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

	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
	if (!skb)
		return -ENOMEM;

	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);
	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 (!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_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);

	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. */
	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
		return -EINVAL;

	if (atomic_read(&alg->cra_refcnt) != 1)
		return -EBUSY;

	return crypto_unregister_instance(alg);
}

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 (!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)
		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 (!capable(CAP_NET_ADMIN))
		return -EPERM;

	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 <[email protected]>");
MODULE_DESCRIPTION("Crypto userspace configuration API");
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 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
	65	if (match) {
	66	alg = q;
	67	break;
	68	}
	69	}
	70
	71	up_read(&crypto_alg_sem);
	72
	73	return alg;
	74	}
	75
07a5fa4a SK	76	static int crypto_report_cipher(struct sk_buff skb, struct crypto_alg alg)
	77	{
	78	struct crypto_report_cipher rcipher;
	79
9a5467bf	80	strncpy(rcipher.type, "cipher", sizeof(rcipher.type));
07a5fa4a SK	81
	82	rcipher.blocksize = alg->cra_blocksize;
	83	rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
	84	rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
	85
6662df33 DM	86	if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
	87	sizeof(struct crypto_report_cipher), &rcipher))
	88	goto nla_put_failure;
07a5fa4a SK	89	return 0;
	90
	91	nla_put_failure:
	92	return -EMSGSIZE;
	93	}
	94
540b97c1 SK	95	static int crypto_report_comp(struct sk_buff skb, struct crypto_alg alg)
	96	{
	97	struct crypto_report_comp rcomp;
	98
9a5467bf	99	strncpy(rcomp.type, "compression", sizeof(rcomp.type));
6662df33 DM	100	if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
	101	sizeof(struct crypto_report_comp), &rcomp))
	102	goto nla_put_failure;
540b97c1 SK	103	return 0;
	104
	105	nla_put_failure:
	106	return -EMSGSIZE;
	107	}
	108
a38f7907 SK	109	static int crypto_report_one(struct crypto_alg *alg,
	110	struct crypto_user_alg ualg, struct sk_buff skb)
	111	{
9a5467bf MK	112	strncpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
	113	strncpy(ualg->cru_driver_name, alg->cra_driver_name,
	114	sizeof(ualg->cru_driver_name));
	115	strncpy(ualg->cru_module_name, module_name(alg->cra_module),
	116	sizeof(ualg->cru_module_name));
	117
	118	ualg->cru_type = 0;
	119	ualg->cru_mask = 0;
a38f7907 SK	120	ualg->cru_flags = alg->cra_flags;
	121	ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);
	122
6662df33 DM	123	if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
6662df33 DM	124	goto nla_put_failure;
6c5a86f5 SK	125	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
	126	struct crypto_report_larval rl;
	127
9a5467bf	128	strncpy(rl.type, "larval", sizeof(rl.type));
6662df33 DM	129	if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL,
	130	sizeof(struct crypto_report_larval), &rl))
	131	goto nla_put_failure;
6c5a86f5 SK	132	goto out;
	133	}
	134
b6aa63c0 SK	135	if (alg->cra_type && alg->cra_type->report) {
	136	if (alg->cra_type->report(skb, alg))
	137	goto nla_put_failure;
07a5fa4a SK	138
	139	goto out;
	140	}
	141
	142	switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_LARVAL)) {
	143	case CRYPTO_ALG_TYPE_CIPHER:
	144	if (crypto_report_cipher(skb, alg))
	145	goto nla_put_failure;
	146
540b97c1 SK	147	break;
	148	case CRYPTO_ALG_TYPE_COMPRESS:
	149	if (crypto_report_comp(skb, alg))
	150	goto nla_put_failure;
	151
07a5fa4a	152	break;
b6aa63c0 SK	153	}
b6aa63c0 SK	154
6c5a86f5	155	out:
a38f7907 SK	156	return 0;
	157
	158	nla_put_failure:
	159	return -EMSGSIZE;
	160	}
	161
	162	static int crypto_report_alg(struct crypto_alg *alg,
	163	struct crypto_dump_info *info)
	164	{
	165	struct sk_buff *in_skb = info->in_skb;
	166	struct sk_buff *skb = info->out_skb;
	167	struct nlmsghdr *nlh;
	168	struct crypto_user_alg *ualg;
	169	int err = 0;
	170
15e47304	171	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
a38f7907 SK	172	CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
	173	if (!nlh) {
	174	err = -EMSGSIZE;
	175	goto out;
	176	}
	177
	178	ualg = nlmsg_data(nlh);
	179
	180	err = crypto_report_one(alg, ualg, skb);
	181	if (err) {
	182	nlmsg_cancel(skb, nlh);
	183	goto out;
	184	}
	185
	186	nlmsg_end(skb, nlh);
	187
	188	out:
	189	return err;
	190	}
	191
	192	static int crypto_report(struct sk_buff in_skb, struct nlmsghdr in_nlh,
	193	struct nlattr **attrs)
	194	{
	195	struct crypto_user_alg *p = nlmsg_data(in_nlh);
	196	struct crypto_alg *alg;
	197	struct sk_buff *skb;
	198	struct crypto_dump_info info;
	199	int err;
	200
8fd61d34 MK	201	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	202	return -EINVAL;
	203
e336ed96	204	if (!p->cru_driver_name[0])
a38f7907 SK	205	return -EINVAL;
	206
	207	alg = crypto_alg_match(p, 1);
	208	if (!alg)
	209	return -ENOENT;
	210
	211	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
	212	if (!skb)
	213	return -ENOMEM;
	214
	215	info.in_skb = in_skb;
	216	info.out_skb = skb;
	217	info.nlmsg_seq = in_nlh->nlmsg_seq;
	218	info.nlmsg_flags = 0;
	219
	220	err = crypto_report_alg(alg, &info);
	221	if (err)
	222	return err;
	223
15e47304	224	return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
a38f7907 SK	225	}
	226
	227	static int crypto_dump_report(struct sk_buff skb, struct netlink_callback cb)
	228	{
	229	struct crypto_alg *alg;
	230	struct crypto_dump_info info;
	231	int err;
	232
	233	if (cb->args[0])
	234	goto out;
	235
	236	cb->args[0] = 1;
	237
	238	info.in_skb = cb->skb;
	239	info.out_skb = skb;
	240	info.nlmsg_seq = cb->nlh->nlmsg_seq;
	241	info.nlmsg_flags = NLM_F_MULTI;
	242
	243	list_for_each_entry(alg, &crypto_alg_list, cra_list) {
	244	err = crypto_report_alg(alg, &info);
	245	if (err)
	246	goto out_err;
	247	}
	248
	249	out:
	250	return skb->len;
	251	out_err:
	252	return err;
	253	}
	254
	255	static int crypto_dump_report_done(struct netlink_callback *cb)
	256	{
	257	return 0;
	258	}
	259
	260	static int crypto_update_alg(struct sk_buff skb, struct nlmsghdr nlh,
	261	struct nlattr **attrs)
	262	{
	263	struct crypto_alg *alg;
	264	struct crypto_user_alg *p = nlmsg_data(nlh);
	265	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	266	LIST_HEAD(list);
	267
8fd61d34 MK	268	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	269	return -EINVAL;
	270
a38f7907 SK	271	if (priority && !strlen(p->cru_driver_name))
	272	return -EINVAL;
	273
	274	alg = crypto_alg_match(p, 1);
	275	if (!alg)
	276	return -ENOENT;
	277
	278	down_write(&crypto_alg_sem);
	279
	280	crypto_remove_spawns(alg, &list, NULL);
	281
	282	if (priority)
	283	alg->cra_priority = nla_get_u32(priority);
	284
	285	up_write(&crypto_alg_sem);
	286
	287	crypto_remove_final(&list);
	288
	289	return 0;
	290	}
	291
	292	static int crypto_del_alg(struct sk_buff skb, struct nlmsghdr nlh,
	293	struct nlattr **attrs)
	294	{
	295	struct crypto_alg *alg;
	296	struct crypto_user_alg *p = nlmsg_data(nlh);
	297
8fd61d34 MK	298	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	299	return -EINVAL;
	300
a38f7907 SK	301	alg = crypto_alg_match(p, 1);
	302	if (!alg)
	303	return -ENOENT;
	304
	305	/* We can not unregister core algorithms such as aes-generic.
	306	* We would loose the reference in the crypto_alg_list to this algorithm
	307	* if we try to unregister. Unregistering such an algorithm without
	308	* removing the module is not possible, so we restrict to crypto
	309	* instances that are build from templates. */
	310	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
	311	return -EINVAL;
	312
	313	if (atomic_read(&alg->cra_refcnt) != 1)
	314	return -EBUSY;
	315
ce3fd840	316	return crypto_unregister_instance(alg);
a38f7907 SK	317	}
a38f7907 SK	318
1e122994 SK	319	static struct crypto_alg crypto_user_skcipher_alg(const char name, u32 type,
	320	u32 mask)
	321	{
	322	int err;
	323	struct crypto_alg *alg;
	324
	325	type = crypto_skcipher_type(type);
	326	mask = crypto_skcipher_mask(mask);
	327
	328	for (;;) {
	329	alg = crypto_lookup_skcipher(name, type, mask);
	330	if (!IS_ERR(alg))
	331	return alg;
	332
	333	err = PTR_ERR(alg);
	334	if (err != -EAGAIN)
	335	break;
	336	if (signal_pending(current)) {
	337	err = -EINTR;
	338	break;
	339	}
	340	}
	341
	342	return ERR_PTR(err);
	343	}
	344
	345	static struct crypto_alg crypto_user_aead_alg(const char name, u32 type,
	346	u32 mask)
	347	{
	348	int err;
	349	struct crypto_alg *alg;
	350
	351	type &= ~(CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_GENIV);
	352	type \|= CRYPTO_ALG_TYPE_AEAD;
	353	mask &= ~(CRYPTO_ALG_TYPE_MASK \| CRYPTO_ALG_GENIV);
	354	mask \|= CRYPTO_ALG_TYPE_MASK;
	355
	356	for (;;) {
	357	alg = crypto_lookup_aead(name, type, mask);
	358	if (!IS_ERR(alg))
	359	return alg;
	360
	361	err = PTR_ERR(alg);
	362	if (err != -EAGAIN)
	363	break;
	364	if (signal_pending(current)) {
	365	err = -EINTR;
	366	break;
	367	}
	368	}
	369
	370	return ERR_PTR(err);
	371	}
	372
a38f7907 SK	373	static int crypto_add_alg(struct sk_buff skb, struct nlmsghdr nlh,
	374	struct nlattr **attrs)
	375	{
0cfdec7a	376	int exact = 0;
a38f7907 SK	377	const char *name;
	378	struct crypto_alg *alg;
	379	struct crypto_user_alg *p = nlmsg_data(nlh);
	380	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
	381
8fd61d34 MK	382	if (!null_terminated(p->cru_name) \|\| !null_terminated(p->cru_driver_name))
	383	return -EINVAL;
	384
a38f7907 SK	385	if (strlen(p->cru_driver_name))
	386	exact = 1;
	387
	388	if (priority && !exact)
	389	return -EINVAL;
	390
	391	alg = crypto_alg_match(p, exact);
	392	if (alg)
	393	return -EEXIST;
	394
	395	if (strlen(p->cru_driver_name))
	396	name = p->cru_driver_name;
	397	else
	398	name = p->cru_name;
	399
1e122994 SK	400	switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) {
	401	case CRYPTO_ALG_TYPE_AEAD:
	402	alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask);
	403	break;
	404	case CRYPTO_ALG_TYPE_GIVCIPHER:
	405	case CRYPTO_ALG_TYPE_BLKCIPHER:
	406	case CRYPTO_ALG_TYPE_ABLKCIPHER:
	407	alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask);
	408	break;
	409	default:
	410	alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
	411	}
	412
a38f7907 SK	413	if (IS_ERR(alg))
	414	return PTR_ERR(alg);
	415
	416	down_write(&crypto_alg_sem);
	417
	418	if (priority)
	419	alg->cra_priority = nla_get_u32(priority);
	420
	421	up_write(&crypto_alg_sem);
	422
	423	crypto_mod_put(alg);
	424
	425	return 0;
	426	}
	427
	428	#define MSGSIZE(type) sizeof(struct type)
	429
	430	static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
	431	[CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	432	[CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	433	[CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	434	[CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
	435	};
	436
	437	static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
	438	[CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32},
	439	};
	440
	441	#undef MSGSIZE
	442
a84fb791	443	static const struct crypto_link {
a38f7907 SK	444	int (doit)(struct sk_buff , struct nlmsghdr , struct nlattr *);
	445	int (dump)(struct sk_buff , struct netlink_callback *);
	446	int (done)(struct netlink_callback );
	447	} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
	448	[CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
	449	[CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
	450	[CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
	451	[CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report,
	452	.dump = crypto_dump_report,
	453	.done = crypto_dump_report_done},
	454	};
	455
	456	static int crypto_user_rcv_msg(struct sk_buff skb, struct nlmsghdr nlh)
	457	{
	458	struct nlattr *attrs[CRYPTOCFGA_MAX+1];
a84fb791	459	const struct crypto_link *link;
a38f7907 SK	460	int type, err;
	461
	462	type = nlh->nlmsg_type;
	463	if (type > CRYPTO_MSG_MAX)
	464	return -EINVAL;
	465
	466	type -= CRYPTO_MSG_BASE;
	467	link = &crypto_dispatch[type];
	468
c49c41a4	469	if (!capable(CAP_NET_ADMIN))
a38f7907 SK	470	return -EPERM;
	471
	472	if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
	473	(nlh->nlmsg_flags & NLM_F_DUMP))) {
5219a534 SK	474	struct crypto_alg *alg;
	475	u16 dump_alloc = 0;
	476
a38f7907 SK	477	if (link->dump == NULL)
a38f7907 SK	478	return -EINVAL;
5219a534 SK	479
	480	list_for_each_entry(alg, &crypto_alg_list, cra_list)
	481	dump_alloc += CRYPTO_REPORT_MAXSIZE;
	482
80d326fa PNA	483	{
	484	struct netlink_dump_control c = {
	485	.dump = link->dump,
	486	.done = link->done,
5219a534	487	.min_dump_alloc = dump_alloc,
80d326fa PNA	488	};
	489	return netlink_dump_start(crypto_nlsk, skb, nlh, &c);
	490	}
a38f7907 SK	491	}
	492
	493	err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
	494	crypto_policy);
	495	if (err < 0)
	496	return err;
	497
	498	if (link->doit == NULL)
	499	return -EINVAL;
	500
	501	return link->doit(skb, nlh, attrs);
	502	}
	503
	504	static void crypto_netlink_rcv(struct sk_buff *skb)
	505	{
	506	mutex_lock(&crypto_cfg_mutex);
	507	netlink_rcv_skb(skb, &crypto_user_rcv_msg);
	508	mutex_unlock(&crypto_cfg_mutex);
	509	}
	510
	511	static int __init crypto_user_init(void)
	512	{
a31f2d17 PNA	513	struct netlink_kernel_cfg cfg = {
	514	.input = crypto_netlink_rcv,
	515	};
	516
9f00d977	517	crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg);
a38f7907 SK	518	if (!crypto_nlsk)
	519	return -ENOMEM;
	520
	521	return 0;
	522	}
	523
	524	static void __exit crypto_user_exit(void)
	525	{
	526	netlink_kernel_release(crypto_nlsk);
	527	}
	528
	529	module_init(crypto_user_init);
	530	module_exit(crypto_user_exit);
	531	MODULE_LICENSE("GPL");
	532	MODULE_AUTHOR("Steffen Klassert <[email protected]>");
	533	MODULE_DESCRIPTION("Crypto userspace configuration API");