1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
|
/*
* PIM for Quagga
* Copyright (C) 2008 Everton da Silva Marques
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that 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; see the file COPYING; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <zebra.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/igmp.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <netdb.h>
#include <errno.h>
#include "log.h"
#include "privs.h"
#include "if.h"
#include "vrf.h"
#include "sockopt.h"
#include "pimd.h"
#include "pim_mroute.h"
#include "pim_sock.h"
#include "pim_str.h"
#include "pim_igmp_join.h"
/* GLOBAL VARS */
int pim_socket_raw(int protocol)
{
int fd;
if (pimd_privs.change(ZPRIVS_RAISE))
zlog_err("pim_sockek_raw: could not raise privs, %s",
safe_strerror(errno));
fd = socket(AF_INET, SOCK_RAW, protocol);
if (pimd_privs.change(ZPRIVS_LOWER))
zlog_err("pim_socket_raw: could not lower privs, %s",
safe_strerror(errno));
if (fd < 0) {
zlog_warn("Could not create raw socket: errno=%d: %s", errno,
safe_strerror(errno));
return PIM_SOCK_ERR_SOCKET;
}
return fd;
}
int pim_socket_ip_hdr(int fd)
{
const int on = 1;
int ret;
if (pimd_privs.change(ZPRIVS_RAISE))
zlog_err("%s: could not raise privs, %s", __PRETTY_FUNCTION__,
safe_strerror(errno));
ret = setsockopt(fd, IPPROTO_IP, IP_HDRINCL, &on, sizeof(on));
if (pimd_privs.change(ZPRIVS_LOWER))
zlog_err("%s: could not lower privs, %s", __PRETTY_FUNCTION__,
safe_strerror(errno));
return ret;
}
/*
* Given a socket and a interface,
* Bind that socket to that interface
*/
int pim_socket_bind(int fd, struct interface *ifp)
{
int ret = 0;
#ifdef SO_BINDTODEVICE
if (pimd_privs.change(ZPRIVS_RAISE))
zlog_err("%s: could not raise privs, %s", __PRETTY_FUNCTION__,
safe_strerror(errno));
ret = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, ifp->name,
strlen(ifp->name));
if (pimd_privs.change(ZPRIVS_LOWER))
zlog_err("%s: could not lower privs, %s", __PRETTY_FUNCTION__,
safe_strerror(errno));
#endif
return ret;
}
int pim_socket_mcast(int protocol, struct in_addr ifaddr, struct interface *ifp,
u_char loop)
{
int rcvbuf = 1024 * 1024 * 8;
#ifdef HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
struct ip_mreqn mreq;
#else
struct ip_mreq mreq;
#endif
int fd;
fd = pim_socket_raw(protocol);
if (fd < 0) {
zlog_warn("Could not create multicast socket: errno=%d: %s",
errno, safe_strerror(errno));
return PIM_SOCK_ERR_SOCKET;
}
#ifdef SO_BINDTODEVICE
if (protocol == IPPROTO_PIM) {
int ret;
ret = pim_socket_bind(fd, ifp);
if (ret) {
close(fd);
zlog_warn(
"Could not set fd: %d for interface: %s to device",
fd, ifp->name);
return PIM_SOCK_ERR_BIND;
}
}
#else
/* XXX: use IP_PKTINFO / IP_RECVIF to emulate behaviour? Or change to
* only use 1 socket for all interfaces? */
#endif
/* Needed to obtain destination address from recvmsg() */
{
#if defined(HAVE_IP_PKTINFO)
/* Linux and Solaris IP_PKTINFO */
int opt = 1;
if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &opt, sizeof(opt))) {
zlog_warn(
"Could not set IP_PKTINFO on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
}
#elif defined(HAVE_IP_RECVDSTADDR)
/* BSD IP_RECVDSTADDR */
int opt = 1;
if (setsockopt(fd, IPPROTO_IP, IP_RECVDSTADDR, &opt,
sizeof(opt))) {
zlog_warn(
"Could not set IP_RECVDSTADDR on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
}
#else
zlog_err(
"%s %s: Missing IP_PKTINFO and IP_RECVDSTADDR: unable to get dst addr from recvmsg()",
__FILE__, __PRETTY_FUNCTION__);
close(fd);
return PIM_SOCK_ERR_DSTADDR;
#endif
}
/* Set router alert (RFC 2113) for all IGMP messages (RFC 3376 4.
* Message Formats)*/
if (protocol == IPPROTO_IGMP) {
uint8_t ra[4];
ra[0] = 148;
ra[1] = 4;
ra[2] = 0;
ra[3] = 0;
if (setsockopt(fd, IPPROTO_IP, IP_OPTIONS, ra, 4)) {
zlog_warn(
"Could not set Router Alert Option on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_RA;
}
}
{
int reuse = 1;
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (void *)&reuse,
sizeof(reuse))) {
zlog_warn(
"Could not set Reuse Address Option on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_REUSE;
}
}
{
const int MTTL = 1;
int ttl = MTTL;
if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&ttl,
sizeof(ttl))) {
zlog_warn(
"Could not set multicast TTL=%d on socket fd=%d: errno=%d: %s",
MTTL, fd, errno, safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_TTL;
}
}
if (setsockopt_ipv4_multicast_loop(fd, loop)) {
zlog_warn(
"Could not %s Multicast Loopback Option on socket fd=%d: errno=%d: %s",
loop ? "enable" : "disable", fd, errno,
safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_LOOP;
}
memset(&mreq, 0, sizeof(mreq));
#ifdef HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
mreq.imr_ifindex = ifp->ifindex;
#else
/*
* I am not sure what to do here yet for *BSD
*/
// mreq.imr_interface = ifindex;
#endif
if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF, (void *)&mreq,
sizeof(mreq))) {
zlog_warn(
"Could not set Outgoing Interface Option on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_IFACE;
}
if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf)))
zlog_warn("%s: Failure to set buffer size to %d",
__PRETTY_FUNCTION__, rcvbuf);
{
long flags;
flags = fcntl(fd, F_GETFL, 0);
if (flags < 0) {
zlog_warn(
"Could not get fcntl(F_GETFL,O_NONBLOCK) on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_NONBLOCK_GETFL;
}
if (fcntl(fd, F_SETFL, flags | O_NONBLOCK)) {
zlog_warn(
"Could not set fcntl(F_SETFL,O_NONBLOCK) on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
close(fd);
return PIM_SOCK_ERR_NONBLOCK_SETFL;
}
}
return fd;
}
int pim_socket_join(int fd, struct in_addr group, struct in_addr ifaddr,
ifindex_t ifindex)
{
int ret;
#ifdef HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
struct ip_mreqn opt;
#else
struct ip_mreq opt;
#endif
opt.imr_multiaddr = group;
#ifdef HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
opt.imr_address = ifaddr;
opt.imr_ifindex = ifindex;
#else
opt.imr_interface = ifaddr;
#endif
ret = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &opt, sizeof(opt));
if (ret) {
char group_str[INET_ADDRSTRLEN];
char ifaddr_str[INET_ADDRSTRLEN];
if (!inet_ntop(AF_INET, &group, group_str, sizeof(group_str)))
sprintf(group_str, "<group?>");
if (!inet_ntop(AF_INET, &ifaddr, ifaddr_str,
sizeof(ifaddr_str)))
sprintf(ifaddr_str, "<ifaddr?>");
zlog_err(
"Failure socket joining fd=%d group %s on interface address %s: errno=%d: %s",
fd, group_str, ifaddr_str, errno, safe_strerror(errno));
return ret;
}
if (PIM_DEBUG_TRACE) {
char group_str[INET_ADDRSTRLEN];
char ifaddr_str[INET_ADDRSTRLEN];
if (!inet_ntop(AF_INET, &group, group_str, sizeof(group_str)))
sprintf(group_str, "<group?>");
if (!inet_ntop(AF_INET, &ifaddr, ifaddr_str,
sizeof(ifaddr_str)))
sprintf(ifaddr_str, "<ifaddr?>");
zlog_debug(
"Socket fd=%d joined group %s on interface address %s",
fd, group_str, ifaddr_str);
}
return ret;
}
int pim_socket_join_source(int fd, ifindex_t ifindex, struct in_addr group_addr,
struct in_addr source_addr, const char *ifname)
{
if (pim_igmp_join_source(fd, ifindex, group_addr, source_addr)) {
char group_str[INET_ADDRSTRLEN];
char source_str[INET_ADDRSTRLEN];
pim_inet4_dump("<grp?>", group_addr, group_str,
sizeof(group_str));
pim_inet4_dump("<src?>", source_addr, source_str,
sizeof(source_str));
zlog_warn(
"%s: setsockopt(fd=%d) failure for IGMP group %s source %s ifindex %d on interface %s: errno=%d: %s",
__PRETTY_FUNCTION__, fd, group_str, source_str, ifindex,
ifname, errno, safe_strerror(errno));
return -1;
}
return 0;
}
int pim_socket_recvfromto(int fd, uint8_t *buf, size_t len,
struct sockaddr_in *from, socklen_t *fromlen,
struct sockaddr_in *to, socklen_t *tolen,
ifindex_t *ifindex)
{
struct msghdr msgh;
struct cmsghdr *cmsg;
struct iovec iov;
char cbuf[1000];
int err;
/*
* IP_PKTINFO / IP_RECVDSTADDR don't yield sin_port.
* Use getsockname() to get sin_port.
*/
if (to) {
struct sockaddr_in si;
socklen_t si_len = sizeof(si);
memset(&si, 0, sizeof(si));
to->sin_family = AF_INET;
pim_socket_getsockname(fd, (struct sockaddr *)&si, &si_len);
to->sin_port = si.sin_port;
to->sin_addr = si.sin_addr;
if (tolen)
*tolen = sizeof(si);
}
memset(&msgh, 0, sizeof(struct msghdr));
iov.iov_base = buf;
iov.iov_len = len;
msgh.msg_control = cbuf;
msgh.msg_controllen = sizeof(cbuf);
msgh.msg_name = from;
msgh.msg_namelen = fromlen ? *fromlen : 0;
msgh.msg_iov = &iov;
msgh.msg_iovlen = 1;
msgh.msg_flags = 0;
err = recvmsg(fd, &msgh, 0);
if (err < 0)
return err;
if (fromlen)
*fromlen = msgh.msg_namelen;
for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL;
cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
#ifdef HAVE_IP_PKTINFO
if ((cmsg->cmsg_level == IPPROTO_IP)
&& (cmsg->cmsg_type == IP_PKTINFO)) {
struct in_pktinfo *i =
(struct in_pktinfo *)CMSG_DATA(cmsg);
if (to)
((struct sockaddr_in *)to)->sin_addr =
i->ipi_addr;
if (tolen)
*tolen = sizeof(struct sockaddr_in);
if (ifindex)
*ifindex = i->ipi_ifindex;
break;
}
#endif
#ifdef HAVE_IP_RECVDSTADDR
if ((cmsg->cmsg_level == IPPROTO_IP)
&& (cmsg->cmsg_type == IP_RECVDSTADDR)) {
struct in_addr *i = (struct in_addr *)CMSG_DATA(cmsg);
if (to)
((struct sockaddr_in *)to)->sin_addr = *i;
if (tolen)
*tolen = sizeof(struct sockaddr_in);
break;
}
#endif
#if defined(HAVE_IP_RECVIF) && defined(CMSG_IFINDEX)
if (cmsg->cmsg_type == IP_RECVIF)
if (ifindex)
*ifindex = CMSG_IFINDEX(cmsg);
#endif
} /* for (cmsg) */
return err; /* len */
}
int pim_socket_mcastloop_get(int fd)
{
int loop;
socklen_t loop_len = sizeof(loop);
if (getsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &loop, &loop_len)) {
int e = errno;
zlog_warn(
"Could not get Multicast Loopback Option on socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
errno = e;
return PIM_SOCK_ERR_LOOP;
}
return loop;
}
int pim_socket_getsockname(int fd, struct sockaddr *name, socklen_t *namelen)
{
if (getsockname(fd, name, namelen)) {
int e = errno;
zlog_warn(
"Could not get Socket Name for socket fd=%d: errno=%d: %s",
fd, errno, safe_strerror(errno));
errno = e;
return PIM_SOCK_ERR_NAME;
}
return PIM_SOCK_ERR_NONE;
}
|