[deliverable/linux.git] / net / tipc / udp_media.c

/* net/tipc/udp_media.c: IP bearer support for TIPC
 *
 * Copyright (c) 2015, Ericsson AB
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the names of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/socket.h>
#include <linux/ip.h>
#include <linux/udp.h>
#include <linux/inet.h>
#include <linux/inetdevice.h>
#include <linux/igmp.h>
#include <linux/kernel.h>
#include <linux/workqueue.h>
#include <linux/list.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/udp_tunnel.h>
#include <net/addrconf.h>
#include <linux/tipc_netlink.h>
#include "core.h"
#include "bearer.h"

/* IANA assigned UDP port */
#define UDP_PORT_DEFAULT	6118

static const struct nla_policy tipc_nl_udp_policy[TIPC_NLA_UDP_MAX + 1] = {
	[TIPC_NLA_UDP_UNSPEC]	= {.type = NLA_UNSPEC},
	[TIPC_NLA_UDP_LOCAL]	= {.type = NLA_BINARY,
				   .len = sizeof(struct sockaddr_storage)},
	[TIPC_NLA_UDP_REMOTE]	= {.type = NLA_BINARY,
				   .len = sizeof(struct sockaddr_storage)},
};

/**
 * struct udp_media_addr - IP/UDP addressing information
 *
 * This is the bearer level originating address used in neighbor discovery
 * messages, and all fields should be in network byte order
 */
struct udp_media_addr {
	__be16	proto;
	__be16	udp_port;
	union {
		struct in_addr ipv4;
		struct in6_addr ipv6;
	};
};

/**
 * struct udp_bearer - ip/udp bearer data structure
 * @bearer:	associated generic tipc bearer
 * @ubsock:	bearer associated socket
 * @ifindex:	local address scope
 * @work:	used to schedule deferred work on a bearer
 */
struct udp_bearer {
	struct tipc_bearer __rcu *bearer;
	struct socket *ubsock;
	u32 ifindex;
	struct work_struct work;
};

/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
				    struct udp_media_addr *ua)
{
	memset(addr, 0, sizeof(struct tipc_media_addr));
	addr->media_id = TIPC_MEDIA_TYPE_UDP;
	memcpy(addr->value, ua, sizeof(struct udp_media_addr));
	if (ntohs(ua->proto) == ETH_P_IP) {
		if (ipv4_is_multicast(ua->ipv4.s_addr))
			addr->broadcast = 1;
	} else if (ntohs(ua->proto) == ETH_P_IPV6) {
		if (ipv6_addr_type(&ua->ipv6) & IPV6_ADDR_MULTICAST)
			addr->broadcast = 1;
	} else {
		pr_err("Invalid UDP media address\n");
	}
}

/* tipc_udp_addr2str - convert ip/udp address to string */
static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
{
	struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;

	if (ntohs(ua->proto) == ETH_P_IP)
		snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->udp_port));
	else if (ntohs(ua->proto) == ETH_P_IPV6)
		snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->udp_port));
	else
		pr_err("Invalid UDP media address\n");
	return 0;
}

/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
			     char *msg)
{
	struct udp_media_addr *ua;

	ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
	if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
		return -EINVAL;
	tipc_udp_media_addr_set(a, ua);
	return 0;
}

/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
{
	memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
	msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
	memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
	       sizeof(struct udp_media_addr));
	return 0;
}

/* tipc_send_msg - enqueue a send request */
static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
			     struct tipc_bearer *b,
			     struct tipc_media_addr *dest)
{
	int ttl, err = 0;
	struct udp_bearer *ub;
	struct udp_media_addr *dst = (struct udp_media_addr *)&dest->value;
	struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
	struct sk_buff *clone;
	struct rtable *rt;

	clone = skb_clone(skb, GFP_ATOMIC);
	skb_set_inner_protocol(clone, htons(ETH_P_TIPC));
	ub = rcu_dereference_rtnl(b->media_ptr);
	if (!ub) {
		err = -ENODEV;
		goto tx_error;
	}
	if (dst->proto == htons(ETH_P_IP)) {
		struct flowi4 fl = {
			.daddr = dst->ipv4.s_addr,
			.saddr = src->ipv4.s_addr,
			.flowi4_mark = clone->mark,
			.flowi4_proto = IPPROTO_UDP
		};
		rt = ip_route_output_key(net, &fl);
		if (IS_ERR(rt)) {
			err = PTR_ERR(rt);
			goto tx_error;
		}
		ttl = ip4_dst_hoplimit(&rt->dst);
		err = udp_tunnel_xmit_skb(rt, clone, src->ipv4.s_addr,
					  dst->ipv4.s_addr, 0, ttl, 0,
					  src->udp_port, dst->udp_port,
					  false, true);
		if (err < 0) {
			ip_rt_put(rt);
			goto tx_error;
		}
#if IS_ENABLED(CONFIG_IPV6)
	} else {
		struct dst_entry *ndst;
		struct flowi6 fl6 = {
			.flowi6_oif = ub->ifindex,
			.daddr = dst->ipv6,
			.saddr = src->ipv6,
			.flowi6_proto = IPPROTO_UDP
		};
		err = ip6_dst_lookup(ub->ubsock->sk, &ndst, &fl6);
		if (err)
			goto tx_error;
		ttl = ip6_dst_hoplimit(ndst);
		err = udp_tunnel6_xmit_skb(ndst, clone, ndst->dev, &src->ipv6,
					   &dst->ipv6, 0, ttl, src->udp_port,
					   dst->udp_port, false);
#endif
	}
	return err;

tx_error:
	kfree_skb(clone);
	return err;
}

/* tipc_udp_recv - read data from bearer socket */
static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
{
	struct udp_bearer *ub;
	struct tipc_bearer *b;

	ub = rcu_dereference_sk_user_data(sk);
	if (!ub) {
		pr_err_ratelimited("Failed to get UDP bearer reference");
		kfree_skb(skb);
		return 0;
	}

	skb_pull(skb, sizeof(struct udphdr));
	rcu_read_lock();
	b = rcu_dereference_rtnl(ub->bearer);

	if (b) {
		tipc_rcv(sock_net(sk), skb, b);
		rcu_read_unlock();
		return 0;
	}
	rcu_read_unlock();
	kfree_skb(skb);
	return 0;
}

static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
{
	int err = 0;
	struct ip_mreqn mreqn;
	struct sock *sk = ub->ubsock->sk;

	if (ntohs(remote->proto) == ETH_P_IP) {
		if (!ipv4_is_multicast(remote->ipv4.s_addr))
			return 0;
		mreqn.imr_multiaddr = remote->ipv4;
		mreqn.imr_ifindex = ub->ifindex;
		err = ip_mc_join_group(sk, &mreqn);
#if IS_ENABLED(CONFIG_IPV6)
	} else {
		if (!ipv6_addr_is_multicast(&remote->ipv6))
			return 0;
		err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
						   &remote->ipv6);
#endif
	}
	return err;
}

/**
 * parse_options - build local/remote addresses from configuration
 * @attrs:	netlink config data
 * @ub:		UDP bearer instance
 * @local:	local bearer IP address/port
 * @remote:	peer or multicast IP/port
 */
static int parse_options(struct nlattr *attrs[], struct udp_bearer *ub,
			 struct udp_media_addr *local,
			 struct udp_media_addr *remote)
{
	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
	struct sockaddr_storage *sa_local, *sa_remote;

	if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
		goto err;
	if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX,
			     attrs[TIPC_NLA_BEARER_UDP_OPTS],
			     tipc_nl_udp_policy))
		goto err;
	if (opts[TIPC_NLA_UDP_LOCAL] && opts[TIPC_NLA_UDP_REMOTE]) {
		sa_local = nla_data(opts[TIPC_NLA_UDP_LOCAL]);
		sa_remote = nla_data(opts[TIPC_NLA_UDP_REMOTE]);
	} else {
err:
		pr_err("Invalid UDP bearer configuration");
		return -EINVAL;
	}
	if ((sa_local->ss_family & sa_remote->ss_family) == AF_INET) {
		struct sockaddr_in *ip4;

		ip4 = (struct sockaddr_in *)sa_local;
		local->proto = htons(ETH_P_IP);
		local->udp_port = ip4->sin_port;
		local->ipv4.s_addr = ip4->sin_addr.s_addr;

		ip4 = (struct sockaddr_in *)sa_remote;
		remote->proto = htons(ETH_P_IP);
		remote->udp_port = ip4->sin_port;
		remote->ipv4.s_addr = ip4->sin_addr.s_addr;
		return 0;

#if IS_ENABLED(CONFIG_IPV6)
	} else if ((sa_local->ss_family & sa_remote->ss_family) == AF_INET6) {
		struct sockaddr_in6 *ip6;

		ip6 = (struct sockaddr_in6 *)sa_local;
		local->proto = htons(ETH_P_IPV6);
		local->udp_port = ip6->sin6_port;
		local->ipv6 = ip6->sin6_addr;
		ub->ifindex = ip6->sin6_scope_id;

		ip6 = (struct sockaddr_in6 *)sa_remote;
		remote->proto = htons(ETH_P_IPV6);
		remote->udp_port = ip6->sin6_port;
		remote->ipv6 = ip6->sin6_addr;
		return 0;
#endif
	}
	return -EADDRNOTAVAIL;
}

/**
 * tipc_udp_enable - callback to create a new udp bearer instance
 * @net:	network namespace
 * @b:		pointer to generic tipc_bearer
 * @attrs:	netlink bearer configuration
 *
 * validate the bearer parameters and initialize the udp bearer
 * rtnl_lock should be held
 */
static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
			   struct nlattr *attrs[])
{
	int err = -EINVAL;
	struct udp_bearer *ub;
	struct udp_media_addr *remote;
	struct udp_media_addr local = {0};
	struct udp_port_cfg udp_conf = {0};
	struct udp_tunnel_sock_cfg tuncfg = {NULL};

	ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
	if (!ub)
		return -ENOMEM;

	remote = (struct udp_media_addr *)&b->bcast_addr.value;
	memset(remote, 0, sizeof(struct udp_media_addr));
	err = parse_options(attrs, ub, &local, remote);
	if (err)
		goto err;

	b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
	b->bcast_addr.broadcast = 1;
	rcu_assign_pointer(b->media_ptr, ub);
	rcu_assign_pointer(ub->bearer, b);
	tipc_udp_media_addr_set(&b->addr, &local);
	if (local.proto == htons(ETH_P_IP)) {
		struct net_device *dev;

		dev = __ip_dev_find(net, local.ipv4.s_addr, false);
		if (!dev) {
			err = -ENODEV;
			goto err;
		}
		udp_conf.family = AF_INET;
		udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
		udp_conf.use_udp_checksums = false;
		ub->ifindex = dev->ifindex;
		b->mtu = dev->mtu - sizeof(struct iphdr)
			- sizeof(struct udphdr);
#if IS_ENABLED(CONFIG_IPV6)
	} else if (local.proto == htons(ETH_P_IPV6)) {
		udp_conf.family = AF_INET6;
		udp_conf.use_udp6_tx_checksums = true;
		udp_conf.use_udp6_rx_checksums = true;
		udp_conf.local_ip6 = in6addr_any;
		b->mtu = 1280;
#endif
	} else {
		err = -EAFNOSUPPORT;
		goto err;
	}
	udp_conf.local_udp_port = local.udp_port;
	err = udp_sock_create(net, &udp_conf, &ub->ubsock);
	if (err)
		goto err;
	tuncfg.sk_user_data = ub;
	tuncfg.encap_type = 1;
	tuncfg.encap_rcv = tipc_udp_recv;
	tuncfg.encap_destroy = NULL;
	setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);

	if (enable_mcast(ub, remote))
		goto err;
	return 0;
err:
	kfree(ub);
	return err;
}

/* cleanup_bearer - break the socket/bearer association */
static void cleanup_bearer(struct work_struct *work)
{
	struct udp_bearer *ub = container_of(work, struct udp_bearer, work);

	if (ub->ubsock)
		udp_tunnel_sock_release(ub->ubsock);
	synchronize_net();
	kfree(ub);
}

/* tipc_udp_disable - detach bearer from socket */
static void tipc_udp_disable(struct tipc_bearer *b)
{
	struct udp_bearer *ub;

	ub = rcu_dereference_rtnl(b->media_ptr);
	if (!ub) {
		pr_err("UDP bearer instance not found\n");
		return;
	}
	if (ub->ubsock)
		sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
	RCU_INIT_POINTER(b->media_ptr, NULL);
	RCU_INIT_POINTER(ub->bearer, NULL);

	/* sock_release need to be done outside of rtnl lock */
	INIT_WORK(&ub->work, cleanup_bearer);
	schedule_work(&ub->work);
}

struct tipc_media udp_media_info = {
	.send_msg	= tipc_udp_send_msg,
	.enable_media	= tipc_udp_enable,
	.disable_media	= tipc_udp_disable,
	.addr2str	= tipc_udp_addr2str,
	.addr2msg	= tipc_udp_addr2msg,
	.msg2addr	= tipc_udp_msg2addr,
	.priority	= TIPC_DEF_LINK_PRI,
	.tolerance	= TIPC_DEF_LINK_TOL,
	.window		= TIPC_DEF_LINK_WIN,
	.type_id	= TIPC_MEDIA_TYPE_UDP,
	.hwaddr_len	= 0,
	.name		= "udp"
};
Commit	Line	Data
d0f91938 EH	1	/* net/tipc/udp_media.c: IP bearer support for TIPC
	2	*
	3	* Copyright (c) 2015, Ericsson AB
	4	* All rights reserved.
	5	*
	6	* Redistribution and use in source and binary forms, with or without
	7	* modification, are permitted provided that the following conditions are met:
	8	*
	9	* 1. Redistributions of source code must retain the above copyright
	10	* notice, this list of conditions and the following disclaimer.
	11	* 2. Redistributions in binary form must reproduce the above copyright
	12	* notice, this list of conditions and the following disclaimer in the
	13	* documentation and/or other materials provided with the distribution.
	14	* 3. Neither the names of the copyright holders nor the names of its
	15	* contributors may be used to endorse or promote products derived from
	16	* this software without specific prior written permission.
	17	*
	18	* Alternatively, this software may be distributed under the terms of the
	19	* GNU General Public License ("GPL") version 2 as published by the Free
	20	* Software Foundation.
	21	*
	22	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	23	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	24	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	25	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	26	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	27	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	28	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	29	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	30	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	31	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	32	* POSSIBILITY OF SUCH DAMAGE.
	33	*/
	34
	35	#include <linux/socket.h>
	36	#include <linux/ip.h>
	37	#include <linux/udp.h>
	38	#include <linux/inet.h>
	39	#include <linux/inetdevice.h>
	40	#include <linux/igmp.h>
	41	#include <linux/kernel.h>
	42	#include <linux/workqueue.h>
	43	#include <linux/list.h>
	44	#include <net/sock.h>
	45	#include <net/ip.h>
	46	#include <net/udp_tunnel.h>
446981e5	47	#include <net/addrconf.h>
d0f91938 EH	48	#include <linux/tipc_netlink.h>
	49	#include "core.h"
	50	#include "bearer.h"
	51
	52	/* IANA assigned UDP port */
	53	#define UDP_PORT_DEFAULT 6118
	54
	55	static const struct nla_policy tipc_nl_udp_policy[TIPC_NLA_UDP_MAX + 1] = {
	56	[TIPC_NLA_UDP_UNSPEC] = {.type = NLA_UNSPEC},
	57	[TIPC_NLA_UDP_LOCAL] = {.type = NLA_BINARY,
	58	.len = sizeof(struct sockaddr_storage)},
	59	[TIPC_NLA_UDP_REMOTE] = {.type = NLA_BINARY,
	60	.len = sizeof(struct sockaddr_storage)},
	61	};
	62
	63	/**
	64	* struct udp_media_addr - IP/UDP addressing information
	65	*
	66	* This is the bearer level originating address used in neighbor discovery
	67	* messages, and all fields should be in network byte order
	68	*/
	69	struct udp_media_addr {
	70	__be16 proto;
	71	__be16 udp_port;
	72	union {
	73	struct in_addr ipv4;
	74	struct in6_addr ipv6;
	75	};
	76	};
	77
	78	/**
	79	* struct udp_bearer - ip/udp bearer data structure
	80	* @bearer: associated generic tipc bearer
	81	* @ubsock: bearer associated socket
	82	* @ifindex: local address scope
	83	* @work: used to schedule deferred work on a bearer
	84	*/
	85	struct udp_bearer {
	86	struct tipc_bearer __rcu *bearer;
	87	struct socket *ubsock;
	88	u32 ifindex;
	89	struct work_struct work;
	90	};
	91
	92	/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
	93	static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
	94	struct udp_media_addr *ua)
	95	{
	96	memset(addr, 0, sizeof(struct tipc_media_addr));
	97	addr->media_id = TIPC_MEDIA_TYPE_UDP;
	98	memcpy(addr->value, ua, sizeof(struct udp_media_addr));
	99	if (ntohs(ua->proto) == ETH_P_IP) {
	100	if (ipv4_is_multicast(ua->ipv4.s_addr))
	101	addr->broadcast = 1;
	102	} else if (ntohs(ua->proto) == ETH_P_IPV6) {
	103	if (ipv6_addr_type(&ua->ipv6) & IPV6_ADDR_MULTICAST)
	104	addr->broadcast = 1;
	105	} else {
	106	pr_err("Invalid UDP media address\n");
	107	}
	108	}
	109
	110	/* tipc_udp_addr2str - convert ip/udp address to string */
	111	static int tipc_udp_addr2str(struct tipc_media_addr a, char buf, int size)
112	{
113	struct udp_media_addr ua = (struct udp_media_addr )&a->value;
114
115	if (ntohs(ua->proto) == ETH_P_IP)
116	snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->udp_port));
117	else if (ntohs(ua->proto) == ETH_P_IPV6)
118	snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->udp_port));
119	else
120	pr_err("Invalid UDP media address\n");
121	return 0;
122	}
123
124	/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
125	static int tipc_udp_msg2addr(struct tipc_bearer b, struct tipc_media_addr a,
126	char *msg)
127	{
128	struct udp_media_addr *ua;
129
130	ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
131	if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
132	return -EINVAL;
133	tipc_udp_media_addr_set(a, ua);
134	return 0;
135	}
136
137	/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
138	static int tipc_udp_addr2msg(char msg, struct tipc_media_addr a)
139	{
140	memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
141	msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
142	memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
143	sizeof(struct udp_media_addr));
144	return 0;
145	}
146
147	/* tipc_send_msg - enqueue a send request */
148	static int tipc_udp_send_msg(struct net net, struct sk_buff skb,
149	struct tipc_bearer *b,
150	struct tipc_media_addr *dest)
151	{
152	int ttl, err = 0;
153	struct udp_bearer *ub;
154	struct udp_media_addr dst = (struct udp_media_addr )&dest->value;
155	struct udp_media_addr src = (struct udp_media_addr )&b->addr.value;
156	struct sk_buff *clone;
157	struct rtable *rt;
158
159	clone = skb_clone(skb, GFP_ATOMIC);
160	skb_set_inner_protocol(clone, htons(ETH_P_TIPC));
161	ub = rcu_dereference_rtnl(b->media_ptr);
162	if (!ub) {
163	err = -ENODEV;
164	goto tx_error;
165	}
4fee6be8	166	if (dst->proto == htons(ETH_P_IP)) {
d0f91938 EH	167	struct flowi4 fl = {
	168	.daddr = dst->ipv4.s_addr,
	169	.saddr = src->ipv4.s_addr,
	170	.flowi4_mark = clone->mark,
	171	.flowi4_proto = IPPROTO_UDP
	172	};
	173	rt = ip_route_output_key(net, &fl);
	174	if (IS_ERR(rt)) {
	175	err = PTR_ERR(rt);
	176	goto tx_error;
	177	}
	178	ttl = ip4_dst_hoplimit(&rt->dst);
	179	err = udp_tunnel_xmit_skb(rt, clone, src->ipv4.s_addr,
	180	dst->ipv4.s_addr, 0, ttl, 0,
	181	src->udp_port, dst->udp_port,
	182	false, true);
	183	if (err < 0) {
	184	ip_rt_put(rt);
	185	goto tx_error;
	186	}
	187	#if IS_ENABLED(CONFIG_IPV6)
	188	} else {
	189	struct dst_entry *ndst;
	190	struct flowi6 fl6 = {
	191	.flowi6_oif = ub->ifindex,
	192	.daddr = dst->ipv6,
	193	.saddr = src->ipv6,
	194	.flowi6_proto = IPPROTO_UDP
	195	};
	196	err = ip6_dst_lookup(ub->ubsock->sk, &ndst, &fl6);
	197	if (err)
	198	goto tx_error;
	199	ttl = ip6_dst_hoplimit(ndst);
	200	err = udp_tunnel6_xmit_skb(ndst, clone, ndst->dev, &src->ipv6,
	201	&dst->ipv6, 0, ttl, src->udp_port,
	202	dst->udp_port, false);
	203	#endif
	204	}
	205	return err;
	206
	207	tx_error:
	208	kfree_skb(clone);
	209	return err;
	210	}
	211
	212	/* tipc_udp_recv - read data from bearer socket */
	213	static int tipc_udp_recv(struct sock sk, struct sk_buff skb)
	214	{
	215	struct udp_bearer *ub;
	216	struct tipc_bearer *b;
	217
	218	ub = rcu_dereference_sk_user_data(sk);
	219	if (!ub) {
	220	pr_err_ratelimited("Failed to get UDP bearer reference");
	221	kfree_skb(skb);
	222	return 0;
	223	}
	224
	225	skb_pull(skb, sizeof(struct udphdr));
	226	rcu_read_lock();
	227	b = rcu_dereference_rtnl(ub->bearer);
	228
	229	if (b) {
	230	tipc_rcv(sock_net(sk), skb, b);
231	rcu_read_unlock();
232	return 0;
233	}
234	rcu_read_unlock();
235	kfree_skb(skb);
236	return 0;
237	}
238
239	static int enable_mcast(struct udp_bearer ub, struct udp_media_addr remote)
240	{
241	int err = 0;
242	struct ip_mreqn mreqn;
243	struct sock *sk = ub->ubsock->sk;
244
245	if (ntohs(remote->proto) == ETH_P_IP) {
246	if (!ipv4_is_multicast(remote->ipv4.s_addr))
247	return 0;
248	mreqn.imr_multiaddr = remote->ipv4;
249	mreqn.imr_ifindex = ub->ifindex;
54ff9ef3	250	err = ip_mc_join_group(sk, &mreqn);
446981e5	251	#if IS_ENABLED(CONFIG_IPV6)
d0f91938 EH	252	} else {
	253	if (!ipv6_addr_is_multicast(&remote->ipv6))
	254	return 0;
446981e5 MRL	255	err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
	256	&remote->ipv6);
	257	#endif
d0f91938 EH	258	}
	259	return err;
	260	}
	261
	262	/**
	263	* parse_options - build local/remote addresses from configuration
	264	* @attrs: netlink config data
	265	* @ub: UDP bearer instance
	266	* @local: local bearer IP address/port
	267	* @remote: peer or multicast IP/port
	268	*/
	269	static int parse_options(struct nlattr attrs[], struct udp_bearer ub,
	270	struct udp_media_addr *local,
	271	struct udp_media_addr *remote)
	272	{
	273	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
	274	struct sockaddr_storage sa_local, sa_remote;
	275
	276	if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
	277	goto err;
	278	if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX,
	279	attrs[TIPC_NLA_BEARER_UDP_OPTS],
	280	tipc_nl_udp_policy))
	281	goto err;
	282	if (opts[TIPC_NLA_UDP_LOCAL] && opts[TIPC_NLA_UDP_REMOTE]) {
	283	sa_local = nla_data(opts[TIPC_NLA_UDP_LOCAL]);
	284	sa_remote = nla_data(opts[TIPC_NLA_UDP_REMOTE]);
	285	} else {
	286	err:
	287	pr_err("Invalid UDP bearer configuration");
	288	return -EINVAL;
	289	}
	290	if ((sa_local->ss_family & sa_remote->ss_family) == AF_INET) {
	291	struct sockaddr_in *ip4;
	292
	293	ip4 = (struct sockaddr_in *)sa_local;
	294	local->proto = htons(ETH_P_IP);
	295	local->udp_port = ip4->sin_port;
	296	local->ipv4.s_addr = ip4->sin_addr.s_addr;
	297
	298	ip4 = (struct sockaddr_in *)sa_remote;
	299	remote->proto = htons(ETH_P_IP);
	300	remote->udp_port = ip4->sin_port;
	301	remote->ipv4.s_addr = ip4->sin_addr.s_addr;
	302	return 0;
	303
	304	#if IS_ENABLED(CONFIG_IPV6)
	305	} else if ((sa_local->ss_family & sa_remote->ss_family) == AF_INET6) {
	306	struct sockaddr_in6 *ip6;
	307
	308	ip6 = (struct sockaddr_in6 *)sa_local;
	309	local->proto = htons(ETH_P_IPV6);
	310	local->udp_port = ip6->sin6_port;
	311	local->ipv6 = ip6->sin6_addr;
	312	ub->ifindex = ip6->sin6_scope_id;
	313
	314	ip6 = (struct sockaddr_in6 *)sa_remote;
	315	remote->proto = htons(ETH_P_IPV6);
	316	remote->udp_port = ip6->sin6_port;
	317	remote->ipv6 = ip6->sin6_addr;
	318	return 0;
	319	#endif
	320	}
	321	return -EADDRNOTAVAIL;
322	}
323
324	/**
325	* tipc_udp_enable - callback to create a new udp bearer instance
326	* @net: network namespace
327	* @b: pointer to generic tipc_bearer
328	* @attrs: netlink bearer configuration
329	*
330	* validate the bearer parameters and initialize the udp bearer
331	* rtnl_lock should be held
332	*/
333	static int tipc_udp_enable(struct net net, struct tipc_bearer b,
334	struct nlattr *attrs[])
335	{
336	int err = -EINVAL;
337	struct udp_bearer *ub;
338	struct udp_media_addr *remote;
339	struct udp_media_addr local = {0};
340	struct udp_port_cfg udp_conf = {0};
4fee6be8	341	struct udp_tunnel_sock_cfg tuncfg = {NULL};
d0f91938 EH	342
	343	ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
	344	if (!ub)
	345	return -ENOMEM;
	346
	347	remote = (struct udp_media_addr *)&b->bcast_addr.value;
	348	memset(remote, 0, sizeof(struct udp_media_addr));
	349	err = parse_options(attrs, ub, &local, remote);
	350	if (err)
	351	goto err;
	352
	353	b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
	354	b->bcast_addr.broadcast = 1;
	355	rcu_assign_pointer(b->media_ptr, ub);
	356	rcu_assign_pointer(ub->bearer, b);
	357	tipc_udp_media_addr_set(&b->addr, &local);
4fee6be8	358	if (local.proto == htons(ETH_P_IP)) {
d0f91938 EH	359	struct net_device *dev;
	360
	361	dev = __ip_dev_find(net, local.ipv4.s_addr, false);
	362	if (!dev) {
	363	err = -ENODEV;
	364	goto err;
	365	}
	366	udp_conf.family = AF_INET;
	367	udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
	368	udp_conf.use_udp_checksums = false;
	369	ub->ifindex = dev->ifindex;
	370	b->mtu = dev->mtu - sizeof(struct iphdr)
	371	- sizeof(struct udphdr);
	372	#if IS_ENABLED(CONFIG_IPV6)
4fee6be8	373	} else if (local.proto == htons(ETH_P_IPV6)) {
d0f91938 EH	374	udp_conf.family = AF_INET6;
	375	udp_conf.use_udp6_tx_checksums = true;
	376	udp_conf.use_udp6_rx_checksums = true;
	377	udp_conf.local_ip6 = in6addr_any;
	378	b->mtu = 1280;
	379	#endif
	380	} else {
	381	err = -EAFNOSUPPORT;
	382	goto err;
	383	}
	384	udp_conf.local_udp_port = local.udp_port;
	385	err = udp_sock_create(net, &udp_conf, &ub->ubsock);
	386	if (err)
	387	goto err;
	388	tuncfg.sk_user_data = ub;
	389	tuncfg.encap_type = 1;
	390	tuncfg.encap_rcv = tipc_udp_recv;
	391	tuncfg.encap_destroy = NULL;
	392	setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
	393
	394	if (enable_mcast(ub, remote))
	395	goto err;
	396	return 0;
	397	err:
	398	kfree(ub);
	399	return err;
	400	}
	401
	402	/* cleanup_bearer - break the socket/bearer association */
	403	static void cleanup_bearer(struct work_struct *work)
	404	{
	405	struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
	406
	407	if (ub->ubsock)
	408	udp_tunnel_sock_release(ub->ubsock);
	409	synchronize_net();
	410	kfree(ub);
	411	}
	412
	413	/* tipc_udp_disable - detach bearer from socket */
	414	static void tipc_udp_disable(struct tipc_bearer *b)
	415	{
	416	struct udp_bearer *ub;
	417
	418	ub = rcu_dereference_rtnl(b->media_ptr);
	419	if (!ub) {
	420	pr_err("UDP bearer instance not found\n");
	421	return;
	422	}
	423	if (ub->ubsock)
	424	sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
	425	RCU_INIT_POINTER(b->media_ptr, NULL);
	426	RCU_INIT_POINTER(ub->bearer, NULL);
	427
	428	/* sock_release need to be done outside of rtnl lock */
	429	INIT_WORK(&ub->work, cleanup_bearer);
	430	schedule_work(&ub->work);
	431	}
	432
	433	struct tipc_media udp_media_info = {
	434	.send_msg = tipc_udp_send_msg,
	435	.enable_media = tipc_udp_enable,
	436	.disable_media = tipc_udp_disable,
	437	.addr2str = tipc_udp_addr2str,
438	.addr2msg = tipc_udp_addr2msg,
439	.msg2addr = tipc_udp_msg2addr,
440	.priority = TIPC_DEF_LINK_PRI,
441	.tolerance = TIPC_DEF_LINK_TOL,
442	.window = TIPC_DEF_LINK_WIN,
443	.type_id = TIPC_MEDIA_TYPE_UDP,
444	.hwaddr_len = 0,
445	.name = "udp"
446	};