xref: /freebsd/usr.sbin/ppp/ether.c (revision c17d43407fe04133a94055b0dbc7ea8965654a9f)
1 /*-
2  * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/param.h>
30 #include <sys/socket.h>
31 #include <sys/un.h>
32 #include <netinet/in.h>
33 #include <arpa/inet.h>
34 #include <netdb.h>
35 #include <netgraph.h>
36 #include <net/ethernet.h>
37 #include <net/if.h>
38 #include <net/route.h>
39 #include <netinet/in_systm.h>
40 #include <netinet/ip.h>
41 #include <netgraph/ng_ether.h>
42 #include <netgraph/ng_message.h>
43 #include <netgraph/ng_pppoe.h>
44 #include <netgraph/ng_socket.h>
45 
46 #include <errno.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <sysexits.h>
51 #include <sys/fcntl.h>
52 #if defined(__FreeBSD__) && !defined(NOKLDLOAD)
53 #include <sys/linker.h>
54 #include <sys/module.h>
55 #endif
56 #include <sys/stat.h>
57 #include <sys/uio.h>
58 #include <termios.h>
59 #include <sys/time.h>
60 #include <unistd.h>
61 
62 #include "layer.h"
63 #include "defs.h"
64 #include "mbuf.h"
65 #include "log.h"
66 #include "timer.h"
67 #include "lqr.h"
68 #include "hdlc.h"
69 #include "throughput.h"
70 #include "fsm.h"
71 #include "lcp.h"
72 #include "ccp.h"
73 #include "link.h"
74 #include "async.h"
75 #include "descriptor.h"
76 #include "physical.h"
77 #include "main.h"
78 #include "mp.h"
79 #include "chat.h"
80 #include "auth.h"
81 #include "chap.h"
82 #include "cbcp.h"
83 #include "datalink.h"
84 #include "slcompress.h"
85 #include "iplist.h"
86 #include "ncpaddr.h"
87 #include "ip.h"
88 #include "ipcp.h"
89 #include "filter.h"
90 #ifndef NORADIUS
91 #include "radius.h"
92 #endif
93 #include "ipv6cp.h"
94 #include "ncp.h"
95 #include "bundle.h"
96 #include "id.h"
97 #include "iface.h"
98 #include "ether.h"
99 
100 
101 #define PPPOE_NODE_TYPE_LEN (sizeof NG_PPPOE_NODE_TYPE - 1) /* "PPPoE" */
102 
103 struct etherdevice {
104   struct device dev;			/* What struct physical knows about */
105   int cs;				/* Control socket */
106   int connected;			/* Are we connected yet ? */
107   int timeout;				/* Seconds attempting to connect */
108   char hook[sizeof TUN_NAME + 11];	/* Our socket node hook */
109 };
110 
111 #define device2ether(d) \
112   ((d)->type == ETHER_DEVICE ? (struct etherdevice *)d : NULL)
113 
114 int
115 ether_DeviceSize(void)
116 {
117   return sizeof(struct etherdevice);
118 }
119 
120 static ssize_t
121 ether_Write(struct physical *p, const void *v, size_t n)
122 {
123   struct etherdevice *dev = device2ether(p->handler);
124 
125   return NgSendData(p->fd, dev->hook, v, n) == -1 ? -1 : n;
126 }
127 
128 static ssize_t
129 ether_Read(struct physical *p, void *v, size_t n)
130 {
131   char hook[sizeof TUN_NAME + 11];
132 
133   return NgRecvData(p->fd, v, n, hook);
134 }
135 
136 static int
137 ether_RemoveFromSet(struct physical *p, fd_set *r, fd_set *w, fd_set *e)
138 {
139   struct etherdevice *dev = device2ether(p->handler);
140   int result;
141 
142   if (r && dev->cs >= 0 && FD_ISSET(dev->cs, r)) {
143     FD_CLR(dev->cs, r);
144     log_Printf(LogTIMER, "%s: fdunset(ctrl) %d\n", p->link.name, dev->cs);
145     result = 1;
146   } else
147     result = 0;
148 
149   /* Careful... physical_RemoveFromSet() called us ! */
150 
151   p->handler->removefromset = NULL;
152   result += physical_RemoveFromSet(p, r, w, e);
153   p->handler->removefromset = ether_RemoveFromSet;
154 
155   return result;
156 }
157 
158 static void
159 ether_Free(struct physical *p)
160 {
161   struct etherdevice *dev = device2ether(p->handler);
162 
163   physical_SetDescriptor(p);
164   if (dev->cs != -1)
165     close(dev->cs);
166   free(dev);
167 }
168 
169 static const char *
170 ether_OpenInfo(struct physical *p)
171 {
172   struct etherdevice *dev = device2ether(p->handler);
173 
174   switch (dev->connected) {
175     case CARRIER_PENDING:
176       return "negotiating";
177     case CARRIER_OK:
178       return "established";
179   }
180 
181   return "disconnected";
182 }
183 
184 static void
185 ether_device2iov(struct device *d, struct iovec *iov, int *niov,
186                  int maxiov, int *auxfd, int *nauxfd)
187 {
188   struct etherdevice *dev = device2ether(d);
189   int sz = physical_MaxDeviceSize();
190 
191   iov[*niov].iov_base = realloc(d, sz);
192   if (iov[*niov].iov_base == NULL) {
193     log_Printf(LogALERT, "Failed to allocate memory: %d\n", sz);
194     AbortProgram(EX_OSERR);
195   }
196   iov[*niov].iov_len = sz;
197   (*niov)++;
198 
199   if (dev->cs >= 0) {
200     *auxfd = dev->cs;
201     (*nauxfd)++;
202   }
203 }
204 
205 static void
206 ether_MessageIn(struct etherdevice *dev)
207 {
208   char msgbuf[sizeof(struct ng_mesg) + sizeof(struct ngpppoe_sts)];
209   struct ng_mesg *rep = (struct ng_mesg *)msgbuf;
210   struct ngpppoe_sts *sts = (struct ngpppoe_sts *)(msgbuf + sizeof *rep);
211   char unknown[14];
212   const char *msg;
213   struct timeval t;
214   fd_set *r;
215   int ret;
216 
217   if (dev->cs < 0)
218     return;
219 
220   if ((r = mkfdset()) == NULL) {
221     log_Printf(LogERROR, "DoLoop: Cannot create fd_set\n");
222     return;
223   }
224   zerofdset(r);
225   FD_SET(dev->cs, r);
226   t.tv_sec = t.tv_usec = 0;
227   ret = select(dev->cs + 1, r, NULL, NULL, &t);
228   free(r);
229 
230   if (ret <= 0)
231     return;
232 
233   if (NgRecvMsg(dev->cs, rep, sizeof msgbuf, NULL) <= 0)
234     return;
235 
236   if (rep->header.version != NG_VERSION) {
237     log_Printf(LogWARN, "%ld: Unexpected netgraph version, expected %ld\n",
238                (long)rep->header.version, (long)NG_VERSION);
239     return;
240   }
241 
242   if (rep->header.typecookie != NGM_PPPOE_COOKIE) {
243     log_Printf(LogWARN, "%ld: Unexpected netgraph cookie, expected %ld\n",
244                (long)rep->header.typecookie, (long)NGM_PPPOE_COOKIE);
245     return;
246   }
247 
248   switch (rep->header.cmd) {
249     case NGM_PPPOE_SET_FLAG:	msg = "SET_FLAG";	break;
250     case NGM_PPPOE_CONNECT:	msg = "CONNECT";	break;
251     case NGM_PPPOE_LISTEN:	msg = "LISTEN";		break;
252     case NGM_PPPOE_OFFER:	msg = "OFFER";		break;
253     case NGM_PPPOE_SUCCESS:	msg = "SUCCESS";	break;
254     case NGM_PPPOE_FAIL:	msg = "FAIL";		break;
255     case NGM_PPPOE_CLOSE:	msg = "CLOSE";		break;
256     case NGM_PPPOE_GET_STATUS:	msg = "GET_STATUS";	break;
257     case NGM_PPPOE_ACNAME:
258       msg = "ACNAME";
259       if (setenv("ACNAME", sts->hook, 1) != 0)
260         log_Printf(LogWARN, "setenv: cannot set ACNAME=%s: %m", sts->hook);
261       break;
262     default:
263       snprintf(unknown, sizeof unknown, "<%d>", (int)rep->header.cmd);
264       msg = unknown;
265       break;
266   }
267 
268   log_Printf(LogPHASE, "Received NGM_PPPOE_%s (hook \"%s\")\n", msg, sts->hook);
269 
270   switch (rep->header.cmd) {
271     case NGM_PPPOE_SUCCESS:
272       dev->connected = CARRIER_OK;
273       break;
274     case NGM_PPPOE_FAIL:
275     case NGM_PPPOE_CLOSE:
276       dev->connected = CARRIER_LOST;
277       break;
278   }
279 }
280 
281 static int
282 ether_AwaitCarrier(struct physical *p)
283 {
284   struct etherdevice *dev = device2ether(p->handler);
285 
286   if (dev->connected != CARRIER_OK && !dev->timeout--)
287     dev->connected = CARRIER_LOST;
288   else if (dev->connected == CARRIER_PENDING)
289     ether_MessageIn(dev);
290 
291   return dev->connected;
292 }
293 
294 static const struct device baseetherdevice = {
295   ETHER_DEVICE,
296   "ether",
297   1492,
298   { CD_REQUIRED, DEF_ETHERCDDELAY },
299   ether_AwaitCarrier,
300   ether_RemoveFromSet,
301   NULL,
302   NULL,
303   NULL,
304   NULL,
305   ether_Free,
306   ether_Read,
307   ether_Write,
308   ether_device2iov,
309   NULL,
310   ether_OpenInfo
311 };
312 
313 struct device *
314 ether_iov2device(int type, struct physical *p, struct iovec *iov, int *niov,
315                  int maxiov, int *auxfd, int *nauxfd)
316 {
317   if (type == ETHER_DEVICE) {
318     struct etherdevice *dev = (struct etherdevice *)iov[(*niov)++].iov_base;
319 
320     dev = realloc(dev, sizeof *dev);	/* Reduce to the correct size */
321     if (dev == NULL) {
322       log_Printf(LogALERT, "Failed to allocate memory: %d\n",
323                  (int)(sizeof *dev));
324       AbortProgram(EX_OSERR);
325     }
326 
327     if (*nauxfd) {
328       dev->cs = *auxfd;
329       (*nauxfd)--;
330     } else
331       dev->cs = -1;
332 
333     /* Refresh function pointers etc */
334     memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
335 
336     physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNCNOACF);
337     return &dev->dev;
338   }
339 
340   return NULL;
341 }
342 
343 static int
344 ether_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w, fd_set *e, int *n)
345 {
346   struct physical *p = descriptor2physical(d);
347   struct etherdevice *dev = device2ether(p->handler);
348   int result;
349 
350   if (r && dev->cs >= 0) {
351     FD_SET(dev->cs, r);
352     log_Printf(LogTIMER, "%s(ctrl): fdset(r) %d\n", p->link.name, dev->cs);
353     result = 1;
354   } else
355     result = 0;
356 
357   result += physical_doUpdateSet(d, r, w, e, n, 0);
358 
359   return result;
360 }
361 
362 static int
363 ether_IsSet(struct fdescriptor *d, const fd_set *fdset)
364 {
365   struct physical *p = descriptor2physical(d);
366   struct etherdevice *dev = device2ether(p->handler);
367   int result;
368 
369   result = dev->cs >= 0 && FD_ISSET(dev->cs, fdset);
370   result += physical_IsSet(d, fdset);
371 
372   return result;
373 }
374 
375 static void
376 ether_DescriptorRead(struct fdescriptor *d, struct bundle *bundle,
377                      const fd_set *fdset)
378 {
379   struct physical *p = descriptor2physical(d);
380   struct etherdevice *dev = device2ether(p->handler);
381 
382   if (dev->cs >= 0 && FD_ISSET(dev->cs, fdset)) {
383     ether_MessageIn(dev);
384     if (dev->connected == CARRIER_LOST) {
385       log_Printf(LogPHASE, "%s: Device disconnected\n", p->link.name);
386       datalink_Down(p->dl, CLOSE_NORMAL);
387       return;
388     }
389   }
390 
391   if (physical_IsSet(d, fdset))
392     physical_DescriptorRead(d, bundle, fdset);
393 }
394 
395 static struct device *
396 ether_Abandon(struct etherdevice *dev, struct physical *p)
397 {
398   /* Abandon our node construction */
399   close(dev->cs);
400   close(p->fd);
401   p->fd = -2;	/* Nobody else need try.. */
402   free(dev);
403 
404   return NULL;
405 }
406 
407 struct device *
408 ether_Create(struct physical *p)
409 {
410   u_char rbuf[2048];
411   struct etherdevice *dev;
412   struct ng_mesg *resp;
413   const struct hooklist *hlist;
414   const struct nodeinfo *ninfo;
415   char *path;
416   int ifacelen, f;
417 
418   dev = NULL;
419   path = NULL;
420   ifacelen = 0;
421   if (p->fd < 0 && !strncasecmp(p->name.full, NG_PPPOE_NODE_TYPE,
422                                 PPPOE_NODE_TYPE_LEN) &&
423       p->name.full[PPPOE_NODE_TYPE_LEN] == ':') {
424     const struct linkinfo *nlink;
425     struct ngpppoe_init_data *data;
426     struct ngm_mkpeer mkp;
427     struct ngm_connect ngc;
428     const char *iface, *provider;
429     char etherid[12];
430     int providerlen;
431     char connectpath[sizeof dev->hook + 2];	/* .:<hook> */
432 
433     p->fd--;				/* We own the device - change fd */
434 
435 #if defined(__FreeBSD__) && !defined(NOKLDLOAD)
436     if (modfind("netgraph") == -1 && ID0kldload("netgraph") == -1) {
437       log_Printf(LogWARN, "kldload: netgraph: %s\n", strerror(errno));
438       return NULL;
439     }
440 
441     if (modfind("ng_ether") == -1 && ID0kldload("ng_ether") == -1)
442       /*
443        * Don't treat this as an error as older kernels have this stuff
444        * built in as part of the netgraph node itself.
445        */
446       log_Printf(LogWARN, "kldload: ng_ether: %s\n", strerror(errno));
447 
448     if (modfind("ng_pppoe") == -1 && ID0kldload("ng_pppoe") == -1) {
449       log_Printf(LogWARN, "kldload: ng_pppoe: %s\n", strerror(errno));
450       return NULL;
451     }
452 
453     if (modfind("ng_socket") == -1 && ID0kldload("ng_socket") == -1) {
454       log_Printf(LogWARN, "kldload: ng_socket: %s\n", strerror(errno));
455       return NULL;
456     }
457 #endif
458 
459     if ((dev = malloc(sizeof *dev)) == NULL)
460       return NULL;
461 
462     iface = p->name.full + PPPOE_NODE_TYPE_LEN + 1;
463 
464     provider = strchr(iface, ':');
465     if (provider) {
466       ifacelen = provider - iface;
467       provider++;
468       providerlen = strlen(provider);
469     } else {
470       ifacelen = strlen(iface);
471       provider = "";
472       providerlen = 0;
473     }
474 
475     /*
476      * We're going to do this (where tunN is our tunnel device):
477      *
478      * .---------.
479      * |  ether  |
480      * | <iface> |                         dev->cs
481      * `---------'                           |
482      *  (orphan)                     p->fd   |
483      *     |                           |     |
484      *     |                           |     |
485      * (ethernet)                      |     |
486      * .---------.                  .-----------.
487      * |  pppoe  |                  |  socket   |
488      * | <iface> |(tunN)<---->(tunN)| <unnamed> |
489      * `---------                   `-----------'
490      *   (tunX)
491      *     ^
492      *     |
493      *     `--->(tunX)
494      */
495 
496     /* Create a socket node */
497     if (ID0NgMkSockNode(NULL, &dev->cs, &p->fd) == -1) {
498       log_Printf(LogWARN, "Cannot create netgraph socket node: %s\n",
499                  strerror(errno));
500       free(dev);
501       return NULL;
502     }
503 
504     /*
505      * Ask for a list of hooks attached to the "ether" node.  This node should
506      * magically exist as a way of hooking stuff onto an ethernet device
507      */
508     path = (char *)alloca(ifacelen + 2);
509     sprintf(path, "%.*s:", ifacelen, iface);
510     if (NgSendMsg(dev->cs, path, NGM_GENERIC_COOKIE, NGM_LISTHOOKS,
511                   NULL, 0) < 0) {
512       log_Printf(LogWARN, "%s Cannot send a netgraph message: %s\n",
513                  path, strerror(errno));
514       return ether_Abandon(dev, p);
515     }
516 
517     /* Get our list back */
518     resp = (struct ng_mesg *)rbuf;
519     if (NgRecvMsg(dev->cs, resp, sizeof rbuf, NULL) <= 0) {
520       log_Printf(LogWARN, "Cannot get netgraph response: %s\n",
521                  strerror(errno));
522       return ether_Abandon(dev, p);
523     }
524 
525     hlist = (const struct hooklist *)resp->data;
526     ninfo = &hlist->nodeinfo;
527 
528     /* Make sure we've got the right type of node */
529     if (strncmp(ninfo->type, NG_ETHER_NODE_TYPE,
530                 sizeof NG_ETHER_NODE_TYPE - 1)) {
531       log_Printf(LogWARN, "%s Unexpected node type ``%s'' (wanted ``"
532                  NG_ETHER_NODE_TYPE "'')\n", path, ninfo->type);
533       return ether_Abandon(dev, p);
534     }
535 
536     log_Printf(LogDEBUG, "List of netgraph node ``%s'' (id %x) hooks:\n",
537                path, ninfo->id);
538 
539     /* look for a hook already attached.  */
540     for (f = 0; f < ninfo->hooks; f++) {
541       nlink = &hlist->link[f];
542 
543       log_Printf(LogDEBUG, "  Found %s -> %s\n", nlink->ourhook,
544                  nlink->peerhook);
545 
546       if (!strcmp(nlink->ourhook, NG_ETHER_HOOK_ORPHAN) ||
547           !strcmp(nlink->ourhook, NG_ETHER_HOOK_DIVERT)) {
548         /*
549          * Something is using the data coming out of this ``ether'' node.
550          * If it's a PPPoE node, we use that node, otherwise we complain that
551          * someone else is using the node.
552          */
553         if (!strcmp(nlink->nodeinfo.type, NG_PPPOE_NODE_TYPE))
554           /* Use this PPPoE node ! */
555           snprintf(ngc.path, sizeof ngc.path, "[%x]:", nlink->nodeinfo.id);
556         else {
557           log_Printf(LogWARN, "%s Node type ``%s'' is currently active\n",
558                      path, nlink->nodeinfo.type);
559           return ether_Abandon(dev, p);
560         }
561         break;
562       }
563     }
564 
565     if (f == ninfo->hooks) {
566       /*
567        * Create a new ``PPPoE'' node connected to the ``ether'' node using
568        * the magic ``orphan'' and ``ethernet'' hooks
569        */
570       snprintf(mkp.type, sizeof mkp.type, "%s", NG_PPPOE_NODE_TYPE);
571       snprintf(mkp.ourhook, sizeof mkp.ourhook, "%s", NG_ETHER_HOOK_ORPHAN);
572       snprintf(mkp.peerhook, sizeof mkp.peerhook, "%s", NG_PPPOE_HOOK_ETHERNET);
573       snprintf(etherid, sizeof etherid, "[%x]:", ninfo->id);
574 
575       log_Printf(LogDEBUG, "Creating PPPoE netgraph node %s%s -> %s\n",
576                  etherid, mkp.ourhook, mkp.peerhook);
577 
578       if (NgSendMsg(dev->cs, etherid, NGM_GENERIC_COOKIE,
579                     NGM_MKPEER, &mkp, sizeof mkp) < 0) {
580         log_Printf(LogWARN, "%s Cannot create PPPoE netgraph node: %s\n",
581                    etherid, strerror(errno));
582         return ether_Abandon(dev, p);
583       }
584 
585       snprintf(ngc.path, sizeof ngc.path, "%s%s", path, NG_ETHER_HOOK_ORPHAN);
586     }
587 
588     snprintf(dev->hook, sizeof dev->hook, "%s%d",
589              TUN_NAME, p->dl->bundle->unit);
590 
591     /*
592      * Connect the PPPoE node to our socket node.
593      * ngc.path has already been set up
594      */
595     snprintf(ngc.ourhook, sizeof ngc.ourhook, "%s", dev->hook);
596     memcpy(ngc.peerhook, ngc.ourhook, sizeof ngc.peerhook);
597 
598     log_Printf(LogDEBUG, "Connecting netgraph socket .:%s -> %s:%s\n",
599                ngc.ourhook, ngc.path, ngc.peerhook);
600     if (NgSendMsg(dev->cs, ".:", NGM_GENERIC_COOKIE,
601                   NGM_CONNECT, &ngc, sizeof ngc) < 0) {
602       log_Printf(LogWARN, "Cannot connect PPPoE and socket netgraph "
603                  "nodes: %s\n", strerror(errno));
604       return ether_Abandon(dev, p);
605     }
606 
607     /* Bring the Ethernet interface up */
608     path[ifacelen] = '\0';	/* Remove the trailing ':' */
609     if (!iface_SetFlags(path, IFF_UP))
610       log_Printf(LogWARN, "%s: Failed to set the IFF_UP flag on %s\n",
611                  p->link.name, path);
612 
613     /* And finally, request a connection to the given provider */
614 
615     data = (struct ngpppoe_init_data *)alloca(sizeof *data + providerlen);
616     snprintf(data->hook, sizeof data->hook, "%s", dev->hook);
617     memcpy(data->data, provider, providerlen);
618     data->data_len = providerlen;
619 
620     snprintf(connectpath, sizeof connectpath, ".:%s", dev->hook);
621     log_Printf(LogDEBUG, "Sending PPPOE_CONNECT to %s\n", connectpath);
622     if (NgSendMsg(dev->cs, connectpath, NGM_PPPOE_COOKIE,
623                   NGM_PPPOE_CONNECT, data, sizeof *data + providerlen) == -1) {
624       log_Printf(LogWARN, "``%s'': Cannot start netgraph node: %s\n",
625                  connectpath, strerror(errno));
626       return ether_Abandon(dev, p);
627     }
628 
629     /* Hook things up so that we monitor dev->cs */
630     p->desc.UpdateSet = ether_UpdateSet;
631     p->desc.IsSet = ether_IsSet;
632     p->desc.Read = ether_DescriptorRead;
633 
634     memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
635     switch (p->cfg.cd.necessity) {
636       case CD_VARIABLE:
637         dev->dev.cd.delay = p->cfg.cd.delay;
638         break;
639       case CD_REQUIRED:
640         dev->dev.cd = p->cfg.cd;
641         break;
642       case CD_NOTREQUIRED:
643         log_Printf(LogWARN, "%s: Carrier must be set, using ``set cd %d!''\n",
644                    p->link.name, dev->dev.cd.delay);
645       case CD_DEFAULT:
646         break;
647     }
648 
649     dev->timeout = dev->dev.cd.delay;
650     dev->connected = CARRIER_PENDING;
651 
652   } else {
653     /* See if we're a netgraph socket */
654     struct stat st;
655 
656     if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
657       struct sockaddr_storage ssock;
658       struct sockaddr *sock = (struct sockaddr *)&ssock;
659       int sz;
660 
661       sz = sizeof ssock;
662       if (getsockname(p->fd, sock, &sz) == -1) {
663         log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
664         close(p->fd);
665         p->fd = -1;
666         return NULL;
667       }
668 
669       if (sock->sa_family == AF_NETGRAPH) {
670         /*
671          * It's a netgraph node... We can't determine hook names etc, so we
672          * stay pretty impartial....
673          */
674         log_Printf(LogPHASE, "%s: Link is a netgraph node\n", p->link.name);
675 
676         if ((dev = malloc(sizeof *dev)) == NULL) {
677           log_Printf(LogWARN, "%s: Cannot allocate an ether device: %s\n",
678                      p->link.name, strerror(errno));
679           return NULL;
680         }
681 
682         memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
683         dev->cs = -1;
684         dev->timeout = 0;
685         dev->connected = CARRIER_OK;
686         *dev->hook = '\0';
687       }
688     }
689   }
690 
691   if (dev) {
692     physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNCNOACF);
693     return &dev->dev;
694   }
695 
696   return NULL;
697 }
698