1/*
2 * OSPF network related functions
3 *   Copyright (C) 1999 Toshiaki Takada
4 *
5 * This file is part of GNU Zebra.
6 *
7 * GNU Zebra is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2, or (at your option) any
10 * later version.
11 *
12 * GNU Zebra is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Zebra; see the file COPYING.  If not, write to the Free
19 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
20 * 02111-1307, USA.
21 */
22
23#include <zebra.h>
24
25#include "thread.h"
26#include "linklist.h"
27#include "prefix.h"
28#include "if.h"
29#include "sockunion.h"
30#include "log.h"
31#include "sockopt.h"
32#include "privs.h"
33
34extern struct zebra_privs_t ospfd_privs;
35
36#include "ospfd/ospfd.h"
37#include "ospfd/ospf_network.h"
38#include "ospfd/ospf_interface.h"
39#include "ospfd/ospf_asbr.h"
40#include "ospfd/ospf_lsa.h"
41#include "ospfd/ospf_lsdb.h"
42#include "ospfd/ospf_neighbor.h"
43#include "ospfd/ospf_packet.h"
44#include "ospfd/ospf_dump.h"
45
46
47
48/* Join to the OSPF ALL SPF ROUTERS multicast group. */
49int
50ospf_if_add_allspfrouters (struct ospf *top, struct prefix *p,
51			   unsigned int ifindex)
52{
53  int ret;
54
55  ret = setsockopt_ipv4_multicast (top->fd, IP_ADD_MEMBERSHIP,
56                                   htonl (OSPF_ALLSPFROUTERS),
57                                   ifindex);
58  if (ret < 0)
59    zlog_warn ("can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
60	       "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
61	       "on # of multicast group memberships has been exceeded?",
62               top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
63  else
64    zlog_debug ("interface %s [%u] join AllSPFRouters Multicast group.",
65	       inet_ntoa (p->u.prefix4), ifindex);
66
67  return ret;
68}
69
70int
71ospf_if_drop_allspfrouters (struct ospf *top, struct prefix *p,
72			    unsigned int ifindex)
73{
74  int ret;
75
76  ret = setsockopt_ipv4_multicast (top->fd, IP_DROP_MEMBERSHIP,
77                                   htonl (OSPF_ALLSPFROUTERS),
78                                   ifindex);
79  if (ret < 0)
80    zlog_warn ("can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
81	       "ifindex %u, AllSPFRouters): %s",
82               top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
83  else
84    zlog_debug ("interface %s [%u] leave AllSPFRouters Multicast group.",
85	        inet_ntoa (p->u.prefix4), ifindex);
86
87  return ret;
88}
89
90/* Join to the OSPF ALL Designated ROUTERS multicast group. */
91int
92ospf_if_add_alldrouters (struct ospf *top, struct prefix *p, unsigned int
93			 ifindex)
94{
95  int ret;
96
97  ret = setsockopt_ipv4_multicast (top->fd, IP_ADD_MEMBERSHIP,
98                                   htonl (OSPF_ALLDROUTERS),
99                                   ifindex);
100  if (ret < 0)
101    zlog_warn ("can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
102	       "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
103	       "on # of multicast group memberships has been exceeded?",
104               top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
105  else
106    zlog_debug ("interface %s [%u] join AllDRouters Multicast group.",
107	        inet_ntoa (p->u.prefix4), ifindex);
108
109  return ret;
110}
111
112int
113ospf_if_drop_alldrouters (struct ospf *top, struct prefix *p, unsigned int
114			  ifindex)
115{
116  int ret;
117
118  ret = setsockopt_ipv4_multicast (top->fd, IP_DROP_MEMBERSHIP,
119                                   htonl (OSPF_ALLDROUTERS),
120                                   ifindex);
121  if (ret < 0)
122    zlog_warn ("can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
123	       "ifindex %u, AllDRouters): %s",
124               top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
125  else
126    zlog_debug ("interface %s [%u] leave AllDRouters Multicast group.",
127	        inet_ntoa (p->u.prefix4), ifindex);
128
129  return ret;
130}
131
132int
133ospf_if_ipmulticast (struct ospf *top, struct prefix *p, unsigned int ifindex)
134{
135  u_char val;
136  int ret, len;
137
138  val = 0;
139  len = sizeof (val);
140
141  /* Prevent receiving self-origined multicast packets. */
142  ret = setsockopt (top->fd, IPPROTO_IP, IP_MULTICAST_LOOP, (void *)&val, len);
143  if (ret < 0)
144    zlog_warn ("can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
145	       top->fd, safe_strerror(errno));
146
147  /* Explicitly set multicast ttl to 1 -- endo. */
148  val = 1;
149  ret = setsockopt (top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val, len);
150  if (ret < 0)
151    zlog_warn ("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
152	       top->fd, safe_strerror (errno));
153
154  ret = setsockopt_ipv4_multicast_if (top->fd, ifindex);
155  if (ret < 0)
156    zlog_warn("can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
157	      "ifindex %u): %s",
158	      top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
159
160  return ret;
161}
162
163int
164ospf_sock_init (void)
165{
166  int ospf_sock;
167  int ret, hincl = 1;
168
169  if ( ospfd_privs.change (ZPRIVS_RAISE) )
170    zlog_err ("ospf_sock_init: could not raise privs, %s",
171               safe_strerror (errno) );
172
173  ospf_sock = socket (AF_INET, SOCK_RAW, IPPROTO_OSPFIGP);
174  if (ospf_sock < 0)
175    {
176      int save_errno = errno;
177      if ( ospfd_privs.change (ZPRIVS_LOWER) )
178        zlog_err ("ospf_sock_init: could not lower privs, %s",
179                   safe_strerror (errno) );
180      zlog_err ("ospf_read_sock_init: socket: %s", safe_strerror (save_errno));
181      exit(1);
182    }
183
184#ifdef IP_HDRINCL
185  /* we will include IP header with packet */
186  ret = setsockopt (ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl, sizeof (hincl));
187  if (ret < 0)
188    {
189      int save_errno = errno;
190      if ( ospfd_privs.change (ZPRIVS_LOWER) )
191        zlog_err ("ospf_sock_init: could not lower privs, %s",
192                   safe_strerror (errno) );
193      zlog_warn ("Can't set IP_HDRINCL option for fd %d: %s",
194      		 ospf_sock, safe_strerror(save_errno));
195    }
196#elif defined (IPTOS_PREC_INTERNETCONTROL)
197#warning "IP_HDRINCL not available on this system"
198#warning "using IPTOS_PREC_INTERNETCONTROL"
199  ret = setsockopt_ipv4_tos(ospf_sock, IPTOS_PREC_INTERNETCONTROL);
200  if (ret < 0)
201    {
202      int save_errno = errno;
203      if ( ospfd_privs.change (ZPRIVS_LOWER) )
204        zlog_err ("ospf_sock_init: could not lower privs, %s",
205                   safe_strerror (errno) );
206      zlog_warn ("can't set sockopt IP_TOS %d to socket %d: %s",
207      		 tos, ospf_sock, safe_strerror(save_errno));
208      close (ospf_sock);	/* Prevent sd leak. */
209      return ret;
210    }
211#else /* !IPTOS_PREC_INTERNETCONTROL */
212#warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
213  zlog_warn ("IP_HDRINCL option not available");
214#endif /* IP_HDRINCL */
215
216  ret = setsockopt_ifindex (AF_INET, ospf_sock, 1);
217
218  if (ret < 0)
219     zlog_warn ("Can't set pktinfo option for fd %d", ospf_sock);
220
221  if (ospfd_privs.change (ZPRIVS_LOWER))
222    {
223      zlog_err ("ospf_sock_init: could not lower privs, %s",
224               safe_strerror (errno) );
225    }
226
227  return ospf_sock;
228}
229
230void
231ospf_adjust_sndbuflen (struct ospf * ospf, unsigned int buflen)
232{
233  int ret, newbuflen;
234  /* Check if any work has to be done at all. */
235  if (ospf->maxsndbuflen >= buflen)
236    return;
237  if (IS_DEBUG_OSPF (zebra, ZEBRA_INTERFACE))
238    zlog_debug ("%s: adjusting OSPF send buffer size to %d",
239      __func__, buflen);
240  if (ospfd_privs.change (ZPRIVS_RAISE))
241    zlog_err ("%s: could not raise privs, %s", __func__,
242      safe_strerror (errno));
243  /* Now we try to set SO_SNDBUF to what our caller has requested
244   * (the MTU of a newly added interface). However, if the OS has
245   * truncated the actual buffer size to somewhat less size, try
246   * to detect it and update our records appropriately. The OS
247   * may allocate more buffer space, than requested, this isn't
248   * a error.
249   */
250  ret = setsockopt_so_sendbuf (ospf->fd, buflen);
251  newbuflen = getsockopt_so_sendbuf (ospf->fd);
252  if (ret < 0 || newbuflen < 0 || newbuflen < (int) buflen)
253    zlog_warn ("%s: tried to set SO_SNDBUF to %u, but got %d",
254      __func__, buflen, newbuflen);
255  if (newbuflen >= 0)
256    ospf->maxsndbuflen = (unsigned int)newbuflen;
257  else
258    zlog_warn ("%s: failed to get SO_SNDBUF", __func__);
259  if (ospfd_privs.change (ZPRIVS_LOWER))
260    zlog_err ("%s: could not lower privs, %s", __func__,
261      safe_strerror (errno));
262}
263