summaryrefslogtreecommitdiffstats
path: root/sysdep/unix/krt-iface.c
blob: 3a50e8b213837e411980342fe503a022f8f12823 (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
/*
 *	BIRD -- Unix Interface Scanning and Syncing
 *
 *	(c) 1998--1999 Martin Mares <mj@ucw.cz>
 *
 *	Can be freely distributed and used under the terms of the GNU GPL.
 */

#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <errno.h>

#define LOCAL_DEBUG

#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "lib/timer.h"
#include "lib/krt.h"

#include "unix.h"

int if_scan_sock = -1;

static void
scan_ifs(struct ifreq *r, int cnt)
{
  struct iface i, *pi;
  struct ifa a;
  char *err, *colon;
  unsigned fl;
  ip_addr netmask;
  int l;
  int sec = 0;

  if_start_update();
  for (cnt /= sizeof(struct ifreq); cnt; cnt--, r++)
    {
      bzero(&i, sizeof(i));
      bzero(&a, sizeof(a));
      DBG("%s\n", r->ifr_name);
      if (colon = strchr(r->ifr_name, ':'))
	{
	  /* It's an alias -- let's interpret it as a secondary interface address */
	  sec = 1;
	  *colon = 0;
	}
      strncpy(i.name, r->ifr_name, sizeof(i.name) - 1);
      get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.ip, NULL);
      if (ipa_nonzero(a.ip))
	{
	  l = ipa_classify(a.ip);
	  if (l < 0 || !(l & IADDR_HOST))
	    {
	      log(L_ERR "%s: Invalid interface address", i.name);
	      a.ip = IPA_NONE;
	    }
	  else
	    {
	      a.scope = l & IADDR_SCOPE_MASK;
	      if (a.scope == SCOPE_HOST)
		i.flags |= IF_LOOPBACK | IF_IGNORE;
	    }
	}

      if (ioctl(if_scan_sock, SIOCGIFFLAGS, r) < 0)
	{
	  err = "SIOCGIFFLAGS";
	faulty:
	  log(L_ERR "%s(%s): %m", err, i.name);
	bad:
	  i.flags = (i.flags & ~IF_LINK_UP) | IF_ADMIN_DOWN;
	  continue;
	}
      fl = r->ifr_flags;
      if (fl & IFF_UP)
	i.flags |= IF_LINK_UP;

      if (ioctl(if_scan_sock, SIOCGIFNETMASK, r) < 0)
	{ err = "SIOCGIFNETMASK"; goto faulty; }
      get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &netmask, NULL);
      l = ipa_mklen(netmask);
      if (l < 0 || l == 31)
	{
	  log(L_ERR "%s: Invalid netmask", i.name);
	  goto bad;
	}
      a.pxlen = l;

      if (fl & IFF_POINTOPOINT)
	{
	  i.flags |= IF_UNNUMBERED;
	  a.pxlen = BITS_PER_IP_ADDRESS;
	  if (ioctl(if_scan_sock, SIOCGIFDSTADDR, r) < 0)
	    { err = "SIOCGIFDSTADDR"; goto faulty; }
	  get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.opposite, NULL);
	}
      if (fl & IFF_LOOPBACK)
	i.flags |= IF_LOOPBACK | IF_IGNORE;
      if (1
#ifndef CONFIG_ALL_MULTICAST
	  && (fl & IFF_MULTICAST)
#endif
#ifndef CONFIG_UNNUM_MULTICAST
	  && !(i.flags & IF_UNNUMBERED)
#endif
	 )
	i.flags |= IF_MULTICAST;

      a.prefix = ipa_and(a.ip, ipa_mkmask(a.pxlen));
      if (a.pxlen < 32)
	{
	  a.brd = ipa_or(a.prefix, ipa_not(ipa_mkmask(a.pxlen)));
	  if (ipa_equal(a.ip, a.prefix) || ipa_equal(a.ip, a.brd))
	    {
	      log(L_ERR "%s: Using network or broadcast address for interface", i.name);
	      goto bad;
	    }
	  if (fl & IFF_BROADCAST)
	    i.flags |= IF_BROADCAST;
	  if (a.pxlen < 30)
	    i.flags |= IF_MULTIACCESS;
	  else
	    a.opposite = ipa_opposite(a.ip);
	}
      else
	a.brd = a.opposite;

      if (ioctl(if_scan_sock, SIOCGIFMTU, r) < 0)
	{ err = "SIOCGIFMTU"; goto faulty; }
      i.mtu = r->ifr_mtu;

#ifdef SIOCGIFINDEX
      if (ioctl(if_scan_sock, SIOCGIFINDEX, r) < 0)
	DBG("SIOCGIFINDEX failed: %m\n");
      else
	i.index = r->ifr_ifindex;
#else
      /*
       *  The kernel doesn't give us real ifindices, but we still need them
       *  at least for OSPF unnumbered links. So let's make them up ourselves.
       */
      if (pi = if_find_by_name(i.name))
	i.index = pi->index;
      else
	{
	  static int if_index_counter = 1;
	  i.index = if_index_counter++;
	}
#endif

      pi = NULL;
      if (sec)
	{
	  a.flags |= IA_SECONDARY;
	  pi = if_find_by_index(i.index);
	}
      if (!pi)
	pi = if_update(&i);
      a.iface = pi;
      ifa_update(&a);
    }
  if_end_update();
}

void
krt_if_scan(struct kif_proto *p)
{
  struct ifconf ic;
  static int last_ifbuf_size = 4*sizeof(struct ifreq);
  int res;

  for(;;)
    {
      if (last_ifbuf_size)
	{
	  struct ifreq *r = alloca(last_ifbuf_size);
	  ic.ifc_ifcu.ifcu_req = r;
	  ic.ifc_len = last_ifbuf_size;
	  res = ioctl(if_scan_sock, SIOCGIFCONF, &ic);
	  if (res < 0 && errno != EFAULT)
	    die("SIOCCGIFCONF: %m");
	  if (res >= 0 && ic.ifc_len < last_ifbuf_size)
	    {
	      scan_ifs(r, ic.ifc_len);
	      break;
	    }
	}
#ifdef CLEAN_WAY_WORKING_ONLY_ON_LINUX_2_1	/* FIXME */
      ic.ifc_req = NULL;
      ic.ifc_len = 999999999;
      if (ioctl(if_scan_sock, SIOCGIFCONF, &ic) < 0)
	die("SIOCIFCONF: %m");
      ic.ifc_len += sizeof(struct ifreq);
      if (last_ifbuf_size < ic.ifc_len)
	{
	  last_ifbuf_size = ic.ifc_len;
	  DBG("Increased ifconf buffer size to %d\n", last_ifbuf_size);
	}
#else
      last_ifbuf_size *= 2;
      DBG("Increased ifconf buffer size to %d\n", last_ifbuf_size);
#endif
    }
}

void
krt_if_construct(struct kif_config *c)
{
}

void
krt_if_start(struct kif_proto *p)
{
}

void
krt_if_shutdown(struct kif_proto *p)
{
}

void
krt_if_io_init(void)
{
  if_scan_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
  DBG("Using socket %d for interface and route scanning\n", if_scan_sock);
  if (if_scan_sock < 0)
    die("Cannot create scanning socket: %m");
}