2 * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
3 * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU Lesser General Public License version 2.1
7 * as published by the Free Software Foundation
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
15 #include <sys/socket.h>
16 #include <sys/ioctl.h>
17 #include <sys/types.h>
19 #include <sys/utsname.h>
21 #include <linux/sockios.h>
22 #include <arpa/inet.h>
30 #include <libubox/usock.h>
31 #include <libubox/uloop.h>
32 #include <libubox/avl-cmp.h>
33 #include <libubox/utils.h>
34 #include "interface.h"
40 interface_send_packet(struct interface
*iface
, struct iovec
*iov
, int iov_len
)
42 static size_t cmsg_data
[( CMSG_SPACE(sizeof(struct in_pktinfo
)) / sizeof(size_t)) + 1];
43 static struct sockaddr_in a
= {
44 .sin_family
= AF_INET
,
45 .sin_port
= htons(MCAST_PORT
),
47 static struct msghdr m
= {
48 .msg_name
= (struct sockaddr
*) &a
,
49 .msg_namelen
= sizeof(a
),
50 .msg_control
= cmsg_data
,
51 .msg_controllen
= CMSG_LEN(sizeof(struct in_pktinfo
)),
53 struct in_pktinfo
*pkti
;
55 int fd
= iface
->fd
.fd
;
58 m
.msg_iovlen
= iov_len
;
60 memset(cmsg_data
, 0, sizeof(cmsg_data
));
61 cmsg
= CMSG_FIRSTHDR(&m
);
62 cmsg
->cmsg_len
= m
.msg_controllen
;
63 cmsg
->cmsg_level
= IPPROTO_IP
;
64 cmsg
->cmsg_type
= IP_PKTINFO
;
66 pkti
= (struct in_pktinfo
*) CMSG_DATA(cmsg
);
67 pkti
->ipi_ifindex
= iface
->ifindex
;
69 a
.sin_addr
.s_addr
= inet_addr(MCAST_ADDR
);
71 return sendmsg(fd
, &m
, 0);
74 static void interface_close(struct interface
*iface
)
80 uloop_fd_delete(&iface
->fd
);
85 static void interface_free(struct interface
*iface
)
87 interface_close(iface
);
92 read_socket(struct uloop_fd
*u
, unsigned int events
)
94 struct interface
*iface
= container_of(u
, struct interface
, fd
);
95 static uint8_t buffer
[8 * 1024];
99 interface_close(iface
);
100 uloop_timeout_set(&iface
->reconnect
, 1000);
104 len
= read(u
->fd
, buffer
, sizeof(buffer
));
106 fprintf(stderr
, "read failed: %s\n", strerror(errno
));
110 dns_handle_packet(iface
, buffer
, len
);
114 interface_socket_setup(struct interface
*iface
)
116 struct ip_mreqn mreq
;
120 struct sockaddr_in sa
= { 0 };
121 int fd
= iface
->fd
.fd
;
123 sa
.sin_family
= AF_INET
;
124 sa
.sin_port
= htons(MCAST_PORT
);
125 inet_pton(AF_INET
, MCAST_ADDR
, &sa
.sin_addr
);
127 memset(&mreq
, 0, sizeof(mreq
));
128 mreq
.imr_address
.s_addr
= iface
->v4_addr
.s_addr
;
129 mreq
.imr_multiaddr
= sa
.sin_addr
;
130 mreq
.imr_ifindex
= iface
->ifindex
;
132 if (setsockopt(fd
, IPPROTO_IP
, IP_MULTICAST_TTL
, &ttl
, sizeof(ttl
)) < 0)
133 fprintf(stderr
, "ioctl failed: IP_MULTICAST_TTL\n");
135 if (setsockopt(fd
, SOL_SOCKET
, SO_REUSEADDR
, &yes
, sizeof(yes
)) < 0)
136 fprintf(stderr
, "ioctl failed: SO_REUSEADDR\n");
138 /* Some network drivers have issues with dropping membership of
139 * mcast groups when the iface is down, but don't allow rejoining
140 * when it comes back up. This is an ugly workaround
141 * -- this was copied from avahi --
143 setsockopt(fd
, IPPROTO_IP
, IP_DROP_MEMBERSHIP
, &mreq
, sizeof(mreq
));
145 if (setsockopt(fd
, IPPROTO_IP
, IP_ADD_MEMBERSHIP
, &mreq
, sizeof(mreq
)) < 0) {
146 fprintf(stderr
, "failed to join multicast group: %s\n", strerror(errno
));
152 if (setsockopt(fd
, IPPROTO_IP
, IP_RECVTTL
, &yes
, sizeof(yes
)) < 0)
153 fprintf(stderr
, "ioctl failed: IP_RECVTTL\n");
155 if (setsockopt(fd
, IPPROTO_IP
, IP_PKTINFO
, &yes
, sizeof(yes
)) < 0)
156 fprintf(stderr
, "ioctl failed: IP_PKTINFO\n");
158 if (setsockopt(fd
, IPPROTO_IP
, IP_MULTICAST_LOOP
, &no
, sizeof(no
)) < 0)
159 fprintf(stderr
, "ioctl failed: IP_MULTICAST_LOOP\n");
165 reconnect_socket(struct uloop_timeout
*timeout
)
167 struct interface
*iface
= container_of(timeout
, struct interface
, reconnect
);
169 iface
->fd
.fd
= usock(USOCK_UDP
| USOCK_SERVER
| USOCK_NONBLOCK
, MCAST_ADDR
, "5353");
170 if (iface
->fd
.fd
< 0) {
171 fprintf(stderr
, "failed to add listener: %s\n", strerror(errno
));
175 if (interface_socket_setup(iface
)) {
180 uloop_fd_add(&iface
->fd
, ULOOP_READ
);
181 dns_send_question(iface
, "_services._dns-sd._udp.local", TYPE_PTR
);
182 announce_init(iface
);
186 uloop_timeout_set(timeout
, 1000);
190 static void interface_start(struct interface
*iface
)
192 iface
->fd
.cb
= read_socket
;
193 iface
->reconnect
.cb
= reconnect_socket
;
194 uloop_timeout_set(&iface
->reconnect
, 100);
198 iface_update_cb(struct vlist_tree
*tree
, struct vlist_node
*node_new
,
199 struct vlist_node
*node_old
)
201 struct interface
*iface
;
204 iface
= container_of(node_old
, struct interface
, node
);
205 interface_free(iface
);
209 iface
= container_of(node_new
, struct interface
, node
);
210 interface_start(iface
);
215 get_iface_ipv4(struct interface
*iface
)
217 struct sockaddr_in
*sin
;
221 sock
= socket(AF_INET
, SOCK_DGRAM
, 0);
225 memset(&ir
, 0, sizeof(struct ifreq
));
226 strncpy(ir
.ifr_name
, iface
->name
, sizeof(ir
.ifr_name
));
228 ret
= ioctl(sock
, SIOCGIFADDR
, &ir
);
232 sin
= (struct sockaddr_in
*) &ir
.ifr_addr
;
233 memcpy(&iface
->v4_addr
, &sin
->sin_addr
, sizeof(iface
->v4_addr
));
240 int interface_add(const char *name
)
242 struct interface
*iface
;
245 iface
= calloc_a(sizeof(*iface
),
246 &name_buf
, strlen(name
) + 1);
248 iface
->name
= strcpy(name_buf
, name
);
249 iface
->ifindex
= if_nametoindex(name
);
252 if (iface
->ifindex
<= 0)
255 if (get_iface_ipv4(iface
))
258 vlist_add(&interfaces
, &iface
->node
, name
);
266 VLIST_TREE(interfaces
, avl_strcmp
, iface_update_cb
, false, false);