summaryrefslogtreecommitdiff
path: root/lib/sockopt.c
blob: 1d4063a615e004dab64f7d5c96ad75951d94616e (plain)
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
/* setsockopt functions
 * Copyright (C) 1999 Kunihiro Ishiguro
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra 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, or (at your option) any
 * later version.
 *
 * GNU Zebra 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 GNU Zebra; see the file COPYING.  If not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.  
 */

#include <zebra.h>
#include "log.h"
#include "sockopt.h"

int
setsockopt_so_recvbuf (int sock, int size)
{
  int ret;
  
  if ( (ret = setsockopt (sock, SOL_SOCKET, SO_RCVBUF, (char *)
                          &size, sizeof (int))) < 0);
    zlog_err ("can't setsockopt SO_RCVBUF");

  return ret;
}

static void *
getsockopt_cmsg_data (struct msghdr *msgh, int level, int type)
{
  struct cmsghdr *cmsg;
  void *ptr = NULL;
  
  for (cmsg = CMSG_FIRSTHDR(msgh); 
       cmsg != NULL;
       cmsg = CMSG_NXTHDR(msgh, cmsg))
    if (cmsg->cmsg_level == level && cmsg->cmsg_type)
      return (ptr = CMSG_DATA(cmsg));

  return NULL;
}

#ifdef HAVE_IPV6
/* Set IPv6 packet info to the socket. */
int
setsockopt_ipv6_pktinfo (int sock, int val)
{
  int ret;
    
#ifdef IPV6_RECVPKTINFO		/*2292bis-01*/
  ret = setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_RECVPKTINFO : %s", strerror (errno));
#else	/*RFC2292*/
  ret = setsockopt(sock, IPPROTO_IPV6, IPV6_PKTINFO, &val, sizeof(val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_PKTINFO : %s", strerror (errno));
#endif /* INIA_IPV6 */
  return ret;
}

/* Set multicast hops val to the socket. */
int
setsockopt_ipv6_checksum (int sock, int val)
{
  int ret;

#ifdef GNU_LINUX
  ret = setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
#else
  ret = setsockopt(sock, IPPROTO_IPV6, IPV6_CHECKSUM, &val, sizeof(val));
#endif /* GNU_LINUX */
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_CHECKSUM");
  return ret;
}

/* Set multicast hops val to the socket. */
int
setsockopt_ipv6_multicast_hops (int sock, int val)
{
  int ret;

  ret = setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_MULTICAST_HOPS");
  return ret;
}

/* Set multicast hops val to the socket. */
int
setsockopt_ipv6_unicast_hops (int sock, int val)
{
  int ret;

  ret = setsockopt(sock, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &val, sizeof(val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_UNICAST_HOPS");
  return ret;
}

int
setsockopt_ipv6_hoplimit (int sock, int val)
{
  int ret;

#ifdef IPV6_RECVHOPLIMIT	/*2292bis-01*/
  ret = setsockopt (sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val, sizeof(val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_RECVHOPLIMIT");
#else	/*RFC2292*/
  ret = setsockopt (sock, IPPROTO_IPV6, IPV6_HOPLIMIT, &val, sizeof(val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_HOPLIMIT");
#endif
  return ret;
}

/* Set multicast loop zero to the socket. */
int
setsockopt_ipv6_multicast_loop (int sock, int val)
{
  int ret;
    
  ret = setsockopt (sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val,
		    sizeof (val));
  if (ret < 0)
    zlog_warn ("can't setsockopt IPV6_MULTICAST_LOOP");
  return ret;
}

static int
getsockopt_ipv6_ifindex (struct msghdr *msgh)
{
  struct in6_pktinfo *pktinfo;
  
  pktinfo = getsockopt_cmsg_data (msgh, IPPROTO_IPV6, IPV6_PKTINFO);
  
  return pktinfo->ipi6_ifindex;
}
#endif /* HAVE_IPV6 */


/* Set up a multicast socket options for IPv4
   This is here so that people only have to do their OS multicast mess 
   in one place rather than all through zebra, ospfd, and ripd 
   NB: This is a hookpoint for specific OS functionality */
int
setsockopt_multicast_ipv4(int sock, 
			int optname, 
			struct in_addr if_addr,
			unsigned int mcast_addr,
			unsigned int ifindex)
{

  /* Linux 2.2.0 and up */
#if defined(GNU_LINUX) && LINUX_VERSION_CODE > 131584
  /* This is better because it uses ifindex directly */
  struct ip_mreqn mreqn;
  
  switch (optname)
    {
    case IP_MULTICAST_IF:
    case IP_ADD_MEMBERSHIP:
    case IP_DROP_MEMBERSHIP:
      memset (&mreqn, 0, sizeof(mreqn));

      if (mcast_addr)
	mreqn.imr_multiaddr.s_addr = mcast_addr;
      
      if (ifindex)
	mreqn.imr_ifindex = ifindex;
      else
	mreqn.imr_address = if_addr;
      
      return setsockopt(sock, IPPROTO_IP, optname, (void *)&mreqn, sizeof(mreqn));
      break;

    default:
      /* Can out and give an understandable error */
      errno = EINVAL;
      return -1;
      break;
    }

  /* Example defines for another OS, boilerplate off other code in this
     function, AND handle optname as per other sections for consistency !! */
  /* #elif  defined(BOGON_NIX) && EXAMPLE_VERSION_CODE > -100000 */
  /* Add your favourite OS here! */

#else /* #if OS_TYPE */ 
  /* default OS support */

  struct in_addr m;
  struct ip_mreq mreq;

  switch (optname)
    {
    case IP_MULTICAST_IF:
      m = if_addr;
      
      return setsockopt (sock, IPPROTO_IP, optname, (void *)&m, sizeof(m)); 
      break;

    case IP_ADD_MEMBERSHIP:
    case IP_DROP_MEMBERSHIP:
      memset (&mreq, 0, sizeof(mreq));
      mreq.imr_multiaddr.s_addr = mcast_addr;
      mreq.imr_interface = if_addr;
      
      return setsockopt (sock, 
			 IPPROTO_IP, 
			 optname, 
			 (void *)&mreq, 
			 sizeof(mreq));
      break;
      
    default:
      /* Can out and give an understandable error */
      errno = EINVAL;
      return -1;
      break;
    }
#endif /* #if OS_TYPE */

}

static int
setsockopt_ipv4_ifindex (int sock, int val)
{
  int ret;

#if defined (IP_PKTINFO)
  ret = setsockopt (sock, IPPROTO_IP, IP_PKTINFO, &val, sizeof (val));
#elif defined (IP_RECVIF)
  ret = setsockopt (sock, IPPROTO_IP, IP_RECVIF, &val, sizeof (val));
#else
#warning "Neither IP_PKTINFO nor IP_RECVIF is available."
#warning "Will not be able to receive link info."
#warning "Things might be seriously broken.."
#endif

  if (ret < 0)
    zlog_warn ("Can't set IP_PKTINFO option");
  return ret;
}

/* set appropriate pktinfo socket option 
 * on systems without PKTINFO, sets RECVIF, which only retrieves
 * interface index.
 * Not portable for IPv4, use only setsockopt_ifindex for v4.
 */
static int 
setsockopt_pktinfo (int af, int sock, int val)
{
  int ret = -1;
  
  switch (af)
    {
      case AF_INET:
        /* _ifindex will use PKTINFO if available.. */
        ret = setsockopt_ipv4_ifindex (sock, val);
        break;
#ifdef HAVE_IPV6
      case AF_INET6:
        ret = setsockopt_ipv6_pktinfo (sock, val);
        break;
#endif
      default:
        zlog_warn ("setsockopt_pktinfo: unknown address family %d", af);
    }
  return ret;
}

int
setsockopt_ifindex (int af, int sock, int val)
{
  int ret = -1;
  
  switch (af)
    {
      case AF_INET:
        ret = setsockopt_ipv4_ifindex (sock, val);
        break;
#ifdef HAVE_IPV6
      case AF_INET6:
        ret = setsockopt_ipv6_pktinfo (sock, val);
        break;
#endif
      default:
        zlog_warn ("setsockopt_ifindex: unknown address family %d", af);
    }
  return ret;
}
  
static int
getsockopt_ipv4_ifindex (struct msghdr *msgh)
{
  int ifindex = -1;
#if defined(IP_PKTINFO)
/* Linux pktinfo based ifindex retrieval */
  struct in_pktinfo *pktinfo;
  
  pktinfo = 
    (struct in_pktinfo *)getsockopt_cmsg_data (msgh, IPPROTO_IP, IP_PKTINFO);
  ifindex = pktinfo->ipi_ifindex;
  
#elif defined(IP_RECVIF)
/* BSD/other IP_RECVIF based ifindex retrieval */
#ifndef SUNOS_5
  /* RECVIF, but not SUNOS, so BSD */
  struct sockaddr_dl *sdl;
#endif /* SUNOS_5 */
  /* SUNOS_5 doesn't need a structure to extract ifindex */

#ifndef SUNOS_5
  sdl = 
    (struct sockaddr_dl *)getsockopt_cmsg_data (msgh, IPPROTO_IP, IP_RECVIF);
  ifindex = sdl->sdl_index;
#else /* !SUNOS_5 */
  ifindex = *(uint_t *)getsockopt_cmsg_data (msgh, IPPROTO_IP, IP_RECVIF);
#endif /* SUNOS_5 */

#else /* neither IP_PKTINFO nor IP_RECVIF, broken */

#warning "getsockopt_ipv4_pktinfo_ifindex: dont have PKTINFO or RECVIF"
#warning "things probably will be broken on this platform!"
  /* XXX why not -1 - this is a failure condition. */
  ifindex = 0;
#endif /* IP_PKTINFO */ 
  return ifindex;
}

/* return ifindex, 0 if none found */
int
getsockopt_ifindex (int af, struct msghdr *msgh)
{
  int ifindex = 0;
  
  switch (af)
    {
      case AF_INET:
        return (getsockopt_ipv4_ifindex (msgh));
        break;
#ifdef HAVE_IPV6
      case AF_INET6:
        return (getsockopt_ipv6_ifindex (msgh));
        break;
#endif
      default:
        zlog_warn ("getsockopt_ifindex: unknown address family %d", af);
        return (ifindex = 0);
    }
}

/* swab iph between order system uses for IP_HDRINCL and host order */
void
sockopt_iphdrincl_swab_htosys (struct ip *iph)
{
  /* BSD and derived take iph in network order, except for 
   * ip_len and ip_off
   */
#ifndef HAVE_IP_HDRINCL_BSD_ORDER
  iph->ip_len = htons(iph->ip_len);
  iph->ip_off = htons(iph->ip_off);
#endif /* HAVE_IP_HDRINCL_BSD_ORDER */

  iph->ip_id = htons(iph->ip_id);
}

void
sockopt_iphdrincl_swab_systoh (struct ip *iph)
{
#ifndef HAVE_IP_HDRINCL_BSD_ORDER
  iph->ip_len = ntohs(iph->ip_len);
  iph->ip_off = ntohs(iph->ip_off);
#endif /* HAVE_IP_HDRINCL_BSD_ORDER */

  iph->ip_id = ntohs(iph->ip_id);
}