ether.c revision 71006 
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: head/usr.sbin/ppp/ether.c 71006 2001-01-14 00:54:48Z brian $
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 <netinet/in_systm.h>
38#include <netinet/ip.h>
39#include <netgraph/ng_ether.h>
40#include <netgraph/ng_message.h>
41#include <netgraph/ng_pppoe.h>
42#include <netgraph/ng_socket.h>
43
44#include <errno.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include <string.h>
48#include <sysexits.h>
49#include <sys/fcntl.h>
50#if defined(__FreeBSD__) && !defined(NOKLDLOAD)
51#include <sys/linker.h>
52#include <sys/module.h>
53#endif
54#include <sys/stat.h>
55#include <sys/uio.h>
56#include <termios.h>
57#include <sys/time.h>
58#include <unistd.h>
59
60#include "layer.h"
61#include "defs.h"
62#include "mbuf.h"
63#include "log.h"
64#include "timer.h"
65#include "lqr.h"
66#include "hdlc.h"
67#include "throughput.h"
68#include "fsm.h"
69#include "lcp.h"
70#include "ccp.h"
71#include "link.h"
72#include "async.h"
73#include "descriptor.h"
74#include "physical.h"
75#include "main.h"
76#include "mp.h"
77#include "chat.h"
78#include "auth.h"
79#include "chap.h"
80#include "cbcp.h"
81#include "datalink.h"
82#include "slcompress.h"
83#include "iplist.h"
84#include "ipcp.h"
85#include "filter.h"
86#ifndef NORADIUS
87#include "radius.h"
88#endif
89#include "bundle.h"
90#include "id.h"
91#include "ether.h"
92
93
94#define PPPOE_NODE_TYPE_LEN (sizeof NG_PPPOE_NODE_TYPE - 1) /* "PPPoE" */
95
96struct etherdevice {
97  struct device dev;			/* What struct physical knows about */
98  int cs;				/* Control socket */
99  int connected;			/* Are we connected yet ? */
100  int timeout;				/* Seconds attempting to connect */
101  char hook[sizeof TUN_NAME + 11];	/* Our socket node hook */
102};
103
104#define device2ether(d) \
105  ((d)->type == ETHER_DEVICE ? (struct etherdevice *)d : NULL)
106
107int
108ether_DeviceSize(void)
109{
110  return sizeof(struct etherdevice);
111}
112
113static ssize_t
114ether_Write(struct physical *p, const void *v, size_t n)
115{
116  struct etherdevice *dev = device2ether(p->handler);
117
118  return NgSendData(p->fd, dev->hook, v, n) == -1 ? -1 : n;
119}
120
121static ssize_t
122ether_Read(struct physical *p, void *v, size_t n)
123{
124  char hook[sizeof TUN_NAME + 11];
125
126  return NgRecvData(p->fd, v, n, hook);
127}
128
129static int
130ether_RemoveFromSet(struct physical *p, fd_set *r, fd_set *w, fd_set *e)
131{
132  struct etherdevice *dev = device2ether(p->handler);
133  int result;
134
135  if (r && dev->cs >= 0 && FD_ISSET(dev->cs, r)) {
136    FD_CLR(dev->cs, r);
137    log_Printf(LogTIMER, "%s: fdunset(ctrl) %d\n", p->link.name, dev->cs);
138    result = 1;
139  } else
140    result = 0;
141
142  /* Careful... physical_RemoveFromSet() called us ! */
143
144  p->handler->removefromset = NULL;
145  result += physical_RemoveFromSet(p, r, w, e);
146  p->handler->removefromset = ether_RemoveFromSet;
147
148  return result;
149}
150
151static void
152ether_Free(struct physical *p)
153{
154  struct etherdevice *dev = device2ether(p->handler);
155
156  physical_SetDescriptor(p);
157  if (dev->cs != -1)
158    close(dev->cs);
159  free(dev);
160}
161
162static const char *
163ether_OpenInfo(struct physical *p)
164{
165  struct etherdevice *dev = device2ether(p->handler);
166
167  switch (dev->connected) {
168    case CARRIER_PENDING:
169      return "negotiating";
170    case CARRIER_OK:
171      return "established";
172  }
173
174  return "disconnected";
175}
176
177static void
178ether_device2iov(struct device *d, struct iovec *iov, int *niov,
179                 int maxiov, int *auxfd, int *nauxfd)
180{
181  struct etherdevice *dev = device2ether(d);
182  int sz = physical_MaxDeviceSize();
183
184  iov[*niov].iov_base = realloc(d, sz);
185  if (iov[*niov].iov_base == NULL) {
186    log_Printf(LogALERT, "Failed to allocate memory: %d\n", sz);
187    AbortProgram(EX_OSERR);
188  }
189  iov[*niov].iov_len = sz;
190  (*niov)++;
191
192  if (dev->cs >= 0) {
193    *auxfd = dev->cs;
194    (*nauxfd)++;
195  }
196}
197
198static void
199ether_MessageIn(struct etherdevice *dev)
200{
201  char msgbuf[sizeof(struct ng_mesg) + sizeof(struct ngpppoe_sts)];
202  struct ng_mesg *rep = (struct ng_mesg *)msgbuf;
203  struct ngpppoe_sts *sts = (struct ngpppoe_sts *)(msgbuf + sizeof *rep);
204  char unknown[14];
205  const char *msg;
206  struct timeval t;
207  fd_set *r;
208  int ret;
209
210  if (dev->cs < 0)
211    return;
212
213  if ((r = mkfdset()) == NULL) {
214    log_Printf(LogERROR, "DoLoop: Cannot create fd_set\n");
215    return;
216  }
217  zerofdset(r);
218  FD_SET(dev->cs, r);
219  t.tv_sec = t.tv_usec = 0;
220  ret = select(dev->cs + 1, r, NULL, NULL, &t);
221  free(r);
222
223  if (ret <= 0)
224    return;
225
226  if (NgRecvMsg(dev->cs, rep, sizeof msgbuf, NULL) < 0)
227    return;
228
229  if (rep->header.version != NG_VERSION) {
230    log_Printf(LogWARN, "%ld: Unexpected netgraph version, expected %ld\n",
231               (long)rep->header.version, (long)NG_VERSION);
232    return;
233  }
234
235  if (rep->header.typecookie != NGM_PPPOE_COOKIE) {
236    log_Printf(LogWARN, "%ld: Unexpected netgraph cookie, expected %ld\n",
237               (long)rep->header.typecookie, (long)NGM_PPPOE_COOKIE);
238    return;
239  }
240
241  switch (rep->header.cmd) {
242    case NGM_PPPOE_SET_FLAG:	msg = "SET_FLAG";	break;
243    case NGM_PPPOE_CONNECT:	msg = "CONNECT";	break;
244    case NGM_PPPOE_LISTEN:	msg = "LISTEN";		break;
245    case NGM_PPPOE_OFFER:	msg = "OFFER";		break;
246    case NGM_PPPOE_SUCCESS:	msg = "SUCCESS";	break;
247    case NGM_PPPOE_FAIL:	msg = "FAIL";		break;
248    case NGM_PPPOE_CLOSE:	msg = "CLOSE";		break;
249    case NGM_PPPOE_GET_STATUS:	msg = "GET_STATUS";	break;
250    default:
251      snprintf(unknown, sizeof unknown, "<%d>", (int)rep->header.cmd);
252      msg = unknown;
253      break;
254  }
255
256  log_Printf(LogPHASE, "Received NGM_PPPOE_%s (hook \"%s\")\n", msg, sts->hook);
257
258  switch (rep->header.cmd) {
259    case NGM_PPPOE_SUCCESS:
260      dev->connected = CARRIER_OK;
261      break;
262    case NGM_PPPOE_FAIL:
263    case NGM_PPPOE_CLOSE:
264      dev->connected = CARRIER_LOST;
265      break;
266  }
267}
268
269static int
270ether_AwaitCarrier(struct physical *p)
271{
272  struct etherdevice *dev = device2ether(p->handler);
273
274  if (dev->connected != CARRIER_OK && !dev->timeout--)
275    dev->connected = CARRIER_LOST;
276  else if (dev->connected == CARRIER_PENDING)
277    ether_MessageIn(dev);
278
279  return dev->connected;
280}
281
282static const struct device baseetherdevice = {
283  ETHER_DEVICE,
284  "ether",
285  { CD_REQUIRED, DEF_ETHERCDDELAY },
286  ether_AwaitCarrier,
287  ether_RemoveFromSet,
288  NULL,
289  NULL,
290  NULL,
291  NULL,
292  ether_Free,
293  ether_Read,
294  ether_Write,
295  ether_device2iov,
296  NULL,
297  ether_OpenInfo
298};
299
300struct device *
301ether_iov2device(int type, struct physical *p, struct iovec *iov, int *niov,
302                 int maxiov, int *auxfd, int *nauxfd)
303{
304  if (type == ETHER_DEVICE) {
305    struct etherdevice *dev = (struct etherdevice *)iov[(*niov)++].iov_base;
306
307    dev = realloc(dev, sizeof *dev);	/* Reduce to the correct size */
308    if (dev == NULL) {
309      log_Printf(LogALERT, "Failed to allocate memory: %d\n",
310                 (int)(sizeof *dev));
311      AbortProgram(EX_OSERR);
312    }
313
314    if (*nauxfd) {
315      dev->cs = *auxfd;
316      (*nauxfd)--;
317    } else
318      dev->cs = -1;
319
320    /* Refresh function pointers etc */
321    memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
322
323    physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNCNOACF);
324    return &dev->dev;
325  }
326
327  return NULL;
328}
329
330static int
331ether_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w, fd_set *e, int *n)
332{
333  struct physical *p = descriptor2physical(d);
334  struct etherdevice *dev = device2ether(p->handler);
335  int result;
336
337  if (r && dev->cs >= 0) {
338    FD_SET(dev->cs, r);
339    log_Printf(LogTIMER, "%s(ctrl): fdset(r) %d\n", p->link.name, dev->cs);
340    result = 1;
341  } else
342    result = 0;
343
344  result += physical_doUpdateSet(d, r, w, e, n, 0);
345
346  return result;
347}
348
349static int
350ether_IsSet(struct fdescriptor *d, const fd_set *fdset)
351{
352  struct physical *p = descriptor2physical(d);
353  struct etherdevice *dev = device2ether(p->handler);
354  int result;
355
356  result = dev->cs >= 0 && FD_ISSET(dev->cs, fdset);
357  result += physical_IsSet(d, fdset);
358
359  return result;
360}
361
362static void
363ether_DescriptorRead(struct fdescriptor *d, struct bundle *bundle,
364                     const fd_set *fdset)
365{
366  struct physical *p = descriptor2physical(d);
367  struct etherdevice *dev = device2ether(p->handler);
368
369  if (dev->cs >= 0 && FD_ISSET(dev->cs, fdset)) {
370    ether_MessageIn(dev);
371    if (dev->connected == CARRIER_LOST) {
372      log_Printf(LogPHASE, "%s: Device disconnected\n", p->link.name);
373      datalink_Down(p->dl, CLOSE_NORMAL);
374      return;
375    }
376  }
377
378  if (physical_IsSet(d, fdset))
379    physical_DescriptorRead(d, bundle, fdset);
380}
381
382static struct device *
383ether_Abandon(struct etherdevice *dev, struct physical *p)
384{
385  /* Abandon our node construction */
386  close(dev->cs);
387  close(p->fd);
388  p->fd = -2;	/* Nobody else need try.. */
389  free(dev);
390
391  return NULL;
392}
393
394struct device *
395ether_Create(struct physical *p)
396{
397  u_char rbuf[2048];
398  struct etherdevice *dev;
399  struct ng_mesg *resp;
400  const struct hooklist *hlist;
401  const struct nodeinfo *ninfo;
402  int f;
403
404  dev = NULL;
405  if (p->fd < 0 && !strncasecmp(p->name.full, NG_PPPOE_NODE_TYPE,
406                                PPPOE_NODE_TYPE_LEN) &&
407      p->name.full[PPPOE_NODE_TYPE_LEN] == ':') {
408    const struct linkinfo *nlink;
409    struct ngpppoe_init_data *data;
410    struct ngm_mkpeer mkp;
411    struct ngm_connect ngc;
412    const char *iface, *provider;
413    char *path, etherid[12];
414    int ifacelen, providerlen;
415    char connectpath[sizeof dev->hook + 2];	/* .:<hook> */
416
417    p->fd--;				/* We own the device - change fd */
418
419#if defined(__FreeBSD__) && !defined(NOKLDLOAD)
420    if (modfind("netgraph") == -1) {
421      log_Printf(LogWARN, "Netgraph is not built into the kernel\n");
422      return NULL;
423    }
424
425    if (modfind("ng_ether") == -1 && ID0kldload("ng_ether") == -1)
426      /*
427       * Don't treat this as an error as older kernels have this stuff
428       * built in as part of the netgraph node itself.
429       */
430      log_Printf(LogWARN, "kldload: ng_ether: %s\n", strerror(errno));
431
432    if (modfind("ng_socket") == -1 && ID0kldload("ng_socket") == -1) {
433      log_Printf(LogWARN, "kldload: ng_socket: %s\n", strerror(errno));
434      return NULL;
435    }
436#endif
437
438    if ((dev = malloc(sizeof *dev)) == NULL)
439      return NULL;
440
441    iface = p->name.full + PPPOE_NODE_TYPE_LEN + 1;
442
443    provider = strchr(iface, ':');
444    if (provider) {
445      ifacelen = provider - iface;
446      provider++;
447      providerlen = strlen(provider);
448    } else {
449      ifacelen = strlen(iface);
450      provider = "";
451      providerlen = 0;
452    }
453
454    /*
455     * We're going to do this (where tunN is our tunnel device):
456     *
457     * .---------.
458     * |  ether  |
459     * | <iface> |                         dev->cs
460     * `---------'                           |
461     *  (orphan)                     p->fd   |
462     *     |                           |     |
463     *     |                           |     |
464     * (ethernet)                      |     |
465     * .---------.                  .-----------.
466     * |  pppoe  |                  |  socket   |
467     * | <iface> |(tunN)<---->(tunN)| <unnamed> |
468     * `---------                   `-----------'
469     *   (tunX)
470     *     ^
471     *     |
472     *     `--->(tunX)
473     */
474
475    /* Create a socket node */
476    if (ID0NgMkSockNode(NULL, &dev->cs, &p->fd) == -1) {
477      log_Printf(LogWARN, "Cannot create netgraph socket node: %s\n",
478                 strerror(errno));
479      free(dev);
480      return NULL;
481    }
482
483    /*
484     * Ask for a list of hooks attached to the "ether" node.  This node should
485     * magically exist as a way of hooking stuff onto an ethernet device
486     */
487    path = (char *)alloca(ifacelen + 2);
488    sprintf(path, "%.*s:", ifacelen, iface);
489    if (NgSendMsg(dev->cs, path, NGM_GENERIC_COOKIE, NGM_LISTHOOKS,
490                  NULL, 0) < 0) {
491      log_Printf(LogWARN, "%s Cannot send a netgraph message: %s\n",
492                 path, strerror(errno));
493      return ether_Abandon(dev, p);
494    }
495
496    /* Get our list back */
497    resp = (struct ng_mesg *)rbuf;
498    if (NgRecvMsg(dev->cs, resp, sizeof rbuf, NULL) < 0) {
499      log_Printf(LogWARN, "Cannot get netgraph response: %s\n",
500                 strerror(errno));
501      return ether_Abandon(dev, p);
502    }
503
504    hlist = (const struct hooklist *)resp->data;
505    ninfo = &hlist->nodeinfo;
506
507    /* Make sure we've got the right type of node */
508    if (strncmp(ninfo->type, NG_ETHER_NODE_TYPE,
509                sizeof NG_ETHER_NODE_TYPE - 1)) {
510      log_Printf(LogWARN, "%s Unexpected node type ``%s'' (wanted ``"
511                 NG_ETHER_NODE_TYPE "'')\n", path, ninfo->type);
512      return ether_Abandon(dev, p);
513    }
514
515    log_Printf(LogDEBUG, "List of netgraph node ``%s'' (id %x) hooks:\n",
516               path, ninfo->id);
517
518    /* look for a hook already attached.  */
519    for (f = 0; f < ninfo->hooks; f++) {
520      nlink = &hlist->link[f];
521
522      log_Printf(LogDEBUG, "  Found %s -> %s\n", nlink->ourhook,
523                 nlink->peerhook);
524
525      if (!strcmp(nlink->ourhook, NG_ETHER_HOOK_ORPHAN) ||
526          !strcmp(nlink->ourhook, NG_ETHER_HOOK_DIVERT)) {
527        /*
528         * Something is using the data coming out of this ``ether'' node.
529         * If it's a PPPoE node, we use that node, otherwise we complain that
530         * someone else is using the node.
531         */
532        if (!strcmp(nlink->nodeinfo.type, NG_PPPOE_NODE_TYPE))
533          /* Use this PPPoE node ! */
534          snprintf(ngc.path, sizeof ngc.path, "[%x]:", nlink->nodeinfo.id);
535        else {
536          log_Printf(LogWARN, "%s Node type ``%s'' is currently active\n",
537                     path, nlink->nodeinfo.type);
538          return ether_Abandon(dev, p);
539        }
540        break;
541      }
542    }
543
544    if (f == ninfo->hooks) {
545      /*
546       * Create a new ``PPPoE'' node connected to the ``ether'' node using
547       * the magic ``orphan'' and ``ethernet'' hooks
548       */
549      snprintf(mkp.type, sizeof mkp.type, "%s", NG_PPPOE_NODE_TYPE);
550      snprintf(mkp.ourhook, sizeof mkp.ourhook, "%s", NG_ETHER_HOOK_ORPHAN);
551      snprintf(mkp.peerhook, sizeof mkp.peerhook, "%s", NG_PPPOE_HOOK_ETHERNET);
552      snprintf(etherid, sizeof etherid, "[%x]:", ninfo->id);
553
554      log_Printf(LogDEBUG, "Creating PPPoE netgraph node %s%s -> %s\n",
555                 etherid, mkp.ourhook, mkp.peerhook);
556
557      if (NgSendMsg(dev->cs, etherid, NGM_GENERIC_COOKIE,
558                    NGM_MKPEER, &mkp, sizeof mkp) < 0) {
559        log_Printf(LogWARN, "%s Cannot create PPPoE netgraph node: %s\n",
560                   etherid, strerror(errno));
561        return ether_Abandon(dev, p);
562      }
563
564      snprintf(ngc.path, sizeof ngc.path, "%s%s", path, NG_ETHER_HOOK_ORPHAN);
565    }
566
567    snprintf(dev->hook, sizeof dev->hook, "%s%d",
568             TUN_NAME, p->dl->bundle->unit);
569
570    /*
571     * Connect the PPPoE node to our socket node.
572     * ngc.path has already been set up
573     */
574    snprintf(ngc.ourhook, sizeof ngc.ourhook, "%s", dev->hook);
575    memcpy(ngc.peerhook, ngc.ourhook, sizeof ngc.peerhook);
576
577    log_Printf(LogDEBUG, "Connecting netgraph socket .:%s -> %s:%s\n",
578               ngc.ourhook, ngc.path, ngc.peerhook);
579    if (NgSendMsg(dev->cs, ".:", NGM_GENERIC_COOKIE,
580                  NGM_CONNECT, &ngc, sizeof ngc) < 0) {
581      log_Printf(LogWARN, "Cannot connect PPPoE and socket netgraph "
582                 "nodes: %s\n", strerror(errno));
583      return ether_Abandon(dev, p);
584    }
585
586    /* And finally, request a connection to the given provider */
587
588    data = (struct ngpppoe_init_data *)alloca(sizeof *data + providerlen);
589    snprintf(data->hook, sizeof data->hook, "%s", dev->hook);
590    memcpy(data->data, provider, providerlen);
591    data->data_len = providerlen;
592
593    snprintf(connectpath, sizeof connectpath, ".:%s", dev->hook);
594    log_Printf(LogDEBUG, "Sending PPPOE_CONNECT to %s\n", connectpath);
595    if (NgSendMsg(dev->cs, connectpath, NGM_PPPOE_COOKIE,
596                  NGM_PPPOE_CONNECT, data, sizeof *data + providerlen) == -1) {
597      log_Printf(LogWARN, "``%s'': Cannot start netgraph node: %s\n",
598                 connectpath, strerror(errno));
599      return ether_Abandon(dev, p);
600    }
601
602    /* Hook things up so that we monitor dev->cs */
603    p->desc.UpdateSet = ether_UpdateSet;
604    p->desc.IsSet = ether_IsSet;
605    p->desc.Read = ether_DescriptorRead;
606
607    memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
608    switch (p->cfg.cd.necessity) {
609      case CD_VARIABLE:
610        dev->dev.cd.delay = p->cfg.cd.delay;
611        break;
612      case CD_REQUIRED:
613        dev->dev.cd = p->cfg.cd;
614        break;
615      case CD_NOTREQUIRED:
616        log_Printf(LogWARN, "%s: Carrier must be set, using ``set cd %d!''\n",
617                   p->link.name, dev->dev.cd.delay);
618      case CD_DEFAULT:
619        break;
620    }
621
622    dev->timeout = dev->dev.cd.delay;
623    dev->connected = CARRIER_PENDING;
624
625  } else {
626    /* See if we're a netgraph socket */
627    struct stat st;
628
629    if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
630      struct sockaddr_storage ssock;
631      struct sockaddr *sock = (struct sockaddr *)&ssock;
632      int sz;
633
634      sz = sizeof ssock;
635      if (getsockname(p->fd, sock, &sz) == -1) {
636        log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
637        close(p->fd);
638        p->fd = -1;
639        return NULL;
640      }
641
642      if (sock->sa_family == AF_NETGRAPH) {
643        /*
644         * It's a netgraph node... We can't determine hook names etc, so we
645         * stay pretty impartial....
646         */
647        log_Printf(LogPHASE, "%s: Link is a netgraph node\n", p->link.name);
648
649        if ((dev = malloc(sizeof *dev)) == NULL) {
650          log_Printf(LogWARN, "%s: Cannot allocate an ether device: %s\n",
651                     p->link.name, strerror(errno));
652          return NULL;
653        }
654
655        memcpy(&dev->dev, &baseetherdevice, sizeof dev->dev);
656        dev->cs = -1;
657        dev->timeout = 0;
658        dev->connected = CARRIER_OK;
659        *dev->hook = '\0';
660      }
661    }
662  }
663
664  if (dev) {
665    physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNCNOACF);
666
667    /* Moan about (and fix) invalid LCP configurations */
668    if (p->link.lcp.cfg.mru > 1492) {
669      log_Printf(LogWARN, "%s: Reducing MRU to 1492\n", p->link.name);
670      p->link.lcp.cfg.mru = 1492;
671    }
672    if (p->dl->bundle->cfg.mtu > 1492) {
673      log_Printf(LogWARN, "%s: Reducing MTU to 1492\n", p->link.name);
674      p->dl->bundle->cfg.mtu = 1492;
675    }
676
677    return &dev->dev;
678  }
679
680  return NULL;
681}
682