xref: /freebsd/usr.sbin/ppp/ipcp.c (revision b306c604df541dede4d0f3cc96188bbf5b6719fe)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
5  *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
6  *                           Internet Initiative Japan, Inc (IIJ)
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #include <sys/param.h>
34 #include <netinet/in_systm.h>
35 #include <netinet/in.h>
36 #include <netinet/ip.h>
37 #include <arpa/inet.h>
38 #include <sys/socket.h>
39 #include <net/if.h>
40 #include <net/route.h>
41 #include <netdb.h>
42 #include <sys/un.h>
43 
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <resolv.h>
47 #include <stdarg.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <sys/stat.h>
51 #include <termios.h>
52 #include <unistd.h>
53 
54 #ifndef NONAT
55 #ifdef LOCALNAT
56 #include "alias.h"
57 #else
58 #include <alias.h>
59 #endif
60 #endif
61 
62 #include "layer.h"
63 #include "ua.h"
64 #include "defs.h"
65 #include "command.h"
66 #include "mbuf.h"
67 #include "log.h"
68 #include "timer.h"
69 #include "fsm.h"
70 #include "proto.h"
71 #include "iplist.h"
72 #include "throughput.h"
73 #include "slcompress.h"
74 #include "lqr.h"
75 #include "hdlc.h"
76 #include "lcp.h"
77 #include "ncpaddr.h"
78 #include "ip.h"
79 #include "ipcp.h"
80 #include "filter.h"
81 #include "descriptor.h"
82 #include "vjcomp.h"
83 #include "async.h"
84 #include "ccp.h"
85 #include "link.h"
86 #include "physical.h"
87 #include "mp.h"
88 #ifndef NORADIUS
89 #include "radius.h"
90 #endif
91 #include "ipv6cp.h"
92 #include "ncp.h"
93 #include "bundle.h"
94 #include "id.h"
95 #include "arp.h"
96 #include "systems.h"
97 #include "prompt.h"
98 #include "route.h"
99 #include "iface.h"
100 
101 #undef REJECTED
102 #define	REJECTED(p, x)	((p)->peer_reject & (1<<(x)))
103 #define issep(ch) ((ch) == ' ' || (ch) == '\t')
104 #define isip(ch) (((ch) >= '0' && (ch) <= '9') || (ch) == '.')
105 
106 struct compreq {
107   u_short proto;
108   u_char slots;
109   u_char compcid;
110 };
111 
112 static int IpcpLayerUp(struct fsm *);
113 static void IpcpLayerDown(struct fsm *);
114 static void IpcpLayerStart(struct fsm *);
115 static void IpcpLayerFinish(struct fsm *);
116 static void IpcpInitRestartCounter(struct fsm *, int);
117 static void IpcpSendConfigReq(struct fsm *);
118 static void IpcpSentTerminateReq(struct fsm *);
119 static void IpcpSendTerminateAck(struct fsm *, u_char);
120 static void IpcpDecodeConfig(struct fsm *, u_char *, u_char *, int,
121                              struct fsm_decode *);
122 
123 extern struct libalias *la;
124 
125 static struct fsm_callbacks ipcp_Callbacks = {
126   IpcpLayerUp,
127   IpcpLayerDown,
128   IpcpLayerStart,
129   IpcpLayerFinish,
130   IpcpInitRestartCounter,
131   IpcpSendConfigReq,
132   IpcpSentTerminateReq,
133   IpcpSendTerminateAck,
134   IpcpDecodeConfig,
135   fsm_NullRecvResetReq,
136   fsm_NullRecvResetAck
137 };
138 
139 static const char *
140 protoname(int proto)
141 {
142   static struct {
143     int id;
144     const char *txt;
145   } cftypes[] = {
146     /* Check out the latest ``Assigned numbers'' rfc (rfc1700.txt) */
147     { 1, "IPADDRS" },		/* IP-Addresses */	/* deprecated */
148     { 2, "COMPPROTO" },		/* IP-Compression-Protocol */
149     { 3, "IPADDR" },		/* IP-Address */
150     { 129, "PRIDNS" },		/* 129: Primary DNS Server Address */
151     { 130, "PRINBNS" },		/* 130: Primary NBNS Server Address */
152     { 131, "SECDNS" },		/* 131: Secondary DNS Server Address */
153     { 132, "SECNBNS" }		/* 132: Secondary NBNS Server Address */
154   };
155   unsigned f;
156 
157   for (f = 0; f < sizeof cftypes / sizeof *cftypes; f++)
158     if (cftypes[f].id == proto)
159       return cftypes[f].txt;
160 
161   return NumStr(proto, NULL, 0);
162 }
163 
164 void
165 ipcp_AddInOctets(struct ipcp *ipcp, int n)
166 {
167   throughput_addin(&ipcp->throughput, n);
168 }
169 
170 void
171 ipcp_AddOutOctets(struct ipcp *ipcp, int n)
172 {
173   throughput_addout(&ipcp->throughput, n);
174 }
175 
176 void
177 ipcp_LoadDNS(struct ipcp *ipcp)
178 {
179   int fd;
180 
181   ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr = INADDR_NONE;
182 
183   if (ipcp->ns.resolv != NULL) {
184     free(ipcp->ns.resolv);
185     ipcp->ns.resolv = NULL;
186   }
187   if (ipcp->ns.resolv_nons != NULL) {
188     free(ipcp->ns.resolv_nons);
189     ipcp->ns.resolv_nons = NULL;
190   }
191   ipcp->ns.resolver = 0;
192 
193   if ((fd = open(_PATH_RESCONF, O_RDONLY)) != -1) {
194     struct stat st;
195 
196     if (fstat(fd, &st) == 0) {
197       ssize_t got;
198 
199       /*
200        * Note, ns.resolv and ns.resolv_nons are assumed to always point to
201        * buffers of the same size!  See the strcpy() below.
202        */
203       if ((ipcp->ns.resolv_nons = (char *)malloc(st.st_size + 1)) == NULL)
204         log_Printf(LogERROR, "Failed to malloc %lu for %s: %s\n",
205                    (unsigned long)st.st_size, _PATH_RESCONF, strerror(errno));
206       else if ((ipcp->ns.resolv = (char *)malloc(st.st_size + 1)) == NULL) {
207         log_Printf(LogERROR, "Failed(2) to malloc %lu for %s: %s\n",
208                    (unsigned long)st.st_size, _PATH_RESCONF, strerror(errno));
209         free(ipcp->ns.resolv_nons);
210         ipcp->ns.resolv_nons = NULL;
211       } else if ((got = read(fd, ipcp->ns.resolv, st.st_size)) != st.st_size) {
212         if (got == -1)
213           log_Printf(LogERROR, "Failed to read %s: %s\n",
214                      _PATH_RESCONF, strerror(errno));
215         else
216           log_Printf(LogERROR, "Failed to read %s, got %lu not %lu\n",
217                      _PATH_RESCONF, (unsigned long)got,
218                      (unsigned long)st.st_size);
219         free(ipcp->ns.resolv_nons);
220         ipcp->ns.resolv_nons = NULL;
221         free(ipcp->ns.resolv);
222         ipcp->ns.resolv = NULL;
223       } else {
224         char *cp, *cp_nons, *ncp, ch;
225         int n;
226 
227         ipcp->ns.resolv[st.st_size] = '\0';
228         ipcp->ns.resolver = 1;
229 
230         cp_nons = ipcp->ns.resolv_nons;
231         cp = ipcp->ns.resolv;
232         n = 0;
233 
234         while ((ncp = strstr(cp, "nameserver")) != NULL) {
235           if (ncp != cp) {
236             memcpy(cp_nons, cp, ncp - cp);
237             cp_nons += ncp - cp;
238           }
239           if ((ncp != cp && ncp[-1] != '\n') || !issep(ncp[10])) {
240             memcpy(cp_nons, ncp, 9);
241             cp_nons += 9;
242             cp = ncp + 9;	/* Can't match "nameserver" at cp... */
243             continue;
244           }
245 
246           for (cp = ncp + 11; issep(*cp); cp++)	/* Skip whitespace */
247             ;
248 
249           for (ncp = cp; isip(*ncp); ncp++)		/* Jump over IP */
250             ;
251 
252           ch = *ncp;
253           *ncp = '\0';
254           if (n < 2 && inet_aton(cp, ipcp->ns.dns))
255             n++;
256           *ncp = ch;
257 
258           if ((cp = strchr(ncp, '\n')) == NULL)	/* Point at next line */
259             cp = ncp + strlen(ncp);
260           else
261             cp++;
262         }
263         /*
264          * Note, cp_nons and cp always point to buffers of the same size, so
265          * strcpy is ok!
266          */
267         strcpy(cp_nons, cp);	/* Copy the end - including the NUL */
268         cp_nons += strlen(cp_nons) - 1;
269         while (cp_nons >= ipcp->ns.resolv_nons && *cp_nons == '\n')
270           *cp_nons-- = '\0';
271         if (n == 2 && ipcp->ns.dns[0].s_addr == INADDR_ANY) {
272           ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr;
273           ipcp->ns.dns[1].s_addr = INADDR_ANY;
274         }
275         bundle_AdjustDNS(ipcp->fsm.bundle);
276       }
277     } else
278       log_Printf(LogERROR, "Failed to stat opened %s: %s\n",
279                  _PATH_RESCONF, strerror(errno));
280 
281     close(fd);
282   }
283 }
284 
285 int
286 ipcp_WriteDNS(struct ipcp *ipcp)
287 {
288   const char *paddr;
289   mode_t mask;
290   FILE *fp;
291 
292   if (ipcp->ns.dns[0].s_addr == INADDR_ANY &&
293       ipcp->ns.dns[1].s_addr == INADDR_ANY) {
294     log_Printf(LogIPCP, "%s not modified: All nameservers NAKd\n",
295               _PATH_RESCONF);
296     return 0;
297   }
298 
299   if (ipcp->ns.dns[0].s_addr == INADDR_ANY) {
300     ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr;
301     ipcp->ns.dns[1].s_addr = INADDR_ANY;
302   }
303 
304   mask = umask(022);
305   if ((fp = ID0fopen(_PATH_RESCONF, "w")) != NULL) {
306     umask(mask);
307     if (ipcp->ns.resolv_nons)
308       fputs(ipcp->ns.resolv_nons, fp);
309     paddr = inet_ntoa(ipcp->ns.dns[0]);
310     log_Printf(LogIPCP, "Primary nameserver set to %s\n", paddr);
311     fprintf(fp, "\nnameserver %s\n", paddr);
312     if (ipcp->ns.dns[1].s_addr != INADDR_ANY &&
313         ipcp->ns.dns[1].s_addr != INADDR_NONE &&
314         ipcp->ns.dns[1].s_addr != ipcp->ns.dns[0].s_addr) {
315       paddr = inet_ntoa(ipcp->ns.dns[1]);
316       log_Printf(LogIPCP, "Secondary nameserver set to %s\n", paddr);
317       fprintf(fp, "nameserver %s\n", paddr);
318     }
319     if (fclose(fp) == EOF) {
320       log_Printf(LogERROR, "write(): Failed updating %s: %s\n", _PATH_RESCONF,
321                  strerror(errno));
322       return 0;
323     }
324   } else {
325     umask(mask);
326     log_Printf(LogERROR,"fopen(\"%s\", \"w\") failed: %s\n", _PATH_RESCONF,
327                  strerror(errno));
328   }
329 
330   return 1;
331 }
332 
333 void
334 ipcp_RestoreDNS(struct ipcp *ipcp)
335 {
336   if (ipcp->ns.resolver) {
337     ssize_t got, len;
338     int fd;
339 
340     if ((fd = ID0open(_PATH_RESCONF, O_WRONLY|O_TRUNC, 0644)) != -1) {
341       len = strlen(ipcp->ns.resolv);
342       if ((got = write(fd, ipcp->ns.resolv, len)) != len) {
343         if (got == -1)
344           log_Printf(LogERROR, "Failed rewriting %s: write: %s\n",
345                      _PATH_RESCONF, strerror(errno));
346         else
347           log_Printf(LogERROR, "Failed rewriting %s: wrote %ld of %ld\n",
348                      _PATH_RESCONF, (long)got, (long)len);
349       }
350       close(fd);
351     } else
352       log_Printf(LogERROR, "Failed rewriting %s: open: %s\n", _PATH_RESCONF,
353                  strerror(errno));
354   } else if (remove(_PATH_RESCONF) == -1)
355     log_Printf(LogERROR, "Failed removing %s: %s\n", _PATH_RESCONF,
356                strerror(errno));
357 
358 }
359 
360 int
361 ipcp_Show(struct cmdargs const *arg)
362 {
363   struct ipcp *ipcp = &arg->bundle->ncp.ipcp;
364 
365   prompt_Printf(arg->prompt, "%s [%s]\n", ipcp->fsm.name,
366                 State2Nam(ipcp->fsm.state));
367   if (ipcp->fsm.state == ST_OPENED) {
368     prompt_Printf(arg->prompt, " His side:        %s, %s\n",
369                   inet_ntoa(ipcp->peer_ip), vj2asc(ipcp->peer_compproto));
370     prompt_Printf(arg->prompt, " My side:         %s, %s\n",
371                   inet_ntoa(ipcp->my_ip), vj2asc(ipcp->my_compproto));
372     prompt_Printf(arg->prompt, " Queued packets:  %lu\n",
373                   (unsigned long)ipcp_QueueLen(ipcp));
374   }
375 
376   prompt_Printf(arg->prompt, "\nDefaults:\n");
377   prompt_Printf(arg->prompt, " FSM retry = %us, max %u Config"
378                 " REQ%s, %u Term REQ%s\n", ipcp->cfg.fsm.timeout,
379                 ipcp->cfg.fsm.maxreq, ipcp->cfg.fsm.maxreq == 1 ? "" : "s",
380                 ipcp->cfg.fsm.maxtrm, ipcp->cfg.fsm.maxtrm == 1 ? "" : "s");
381   prompt_Printf(arg->prompt, " My Address:      %s\n",
382                 ncprange_ntoa(&ipcp->cfg.my_range));
383   if (ipcp->cfg.HaveTriggerAddress)
384     prompt_Printf(arg->prompt, " Trigger address: %s\n",
385                   inet_ntoa(ipcp->cfg.TriggerAddress));
386 
387   prompt_Printf(arg->prompt, " VJ compression:  %s (%d slots %s slot "
388                 "compression)\n", command_ShowNegval(ipcp->cfg.vj.neg),
389                 ipcp->cfg.vj.slots, ipcp->cfg.vj.slotcomp ? "with" : "without");
390 
391   if (iplist_isvalid(&ipcp->cfg.peer_list))
392     prompt_Printf(arg->prompt, " His Address:     %s\n",
393                   ipcp->cfg.peer_list.src);
394   else
395     prompt_Printf(arg->prompt, " His Address:     %s\n",
396                   ncprange_ntoa(&ipcp->cfg.peer_range));
397 
398   prompt_Printf(arg->prompt, " DNS:             %s",
399                 ipcp->cfg.ns.dns[0].s_addr == INADDR_NONE ?
400                 "none" : inet_ntoa(ipcp->cfg.ns.dns[0]));
401   if (ipcp->cfg.ns.dns[1].s_addr != INADDR_NONE)
402     prompt_Printf(arg->prompt, ", %s",
403                   inet_ntoa(ipcp->cfg.ns.dns[1]));
404   prompt_Printf(arg->prompt, ", %s\n",
405                 command_ShowNegval(ipcp->cfg.ns.dns_neg));
406   prompt_Printf(arg->prompt, " Resolver DNS:    %s",
407                 ipcp->ns.dns[0].s_addr == INADDR_NONE ?
408                 "none" : inet_ntoa(ipcp->ns.dns[0]));
409   if (ipcp->ns.dns[1].s_addr != INADDR_NONE &&
410       ipcp->ns.dns[1].s_addr != ipcp->ns.dns[0].s_addr)
411     prompt_Printf(arg->prompt, ", %s",
412                   inet_ntoa(ipcp->ns.dns[1]));
413   prompt_Printf(arg->prompt, "\n NetBIOS NS:      %s, ",
414                 inet_ntoa(ipcp->cfg.ns.nbns[0]));
415   prompt_Printf(arg->prompt, "%s\n\n",
416                 inet_ntoa(ipcp->cfg.ns.nbns[1]));
417 
418   throughput_disp(&ipcp->throughput, arg->prompt);
419 
420   return 0;
421 }
422 
423 int
424 ipcp_vjset(struct cmdargs const *arg)
425 {
426   if (arg->argc != arg->argn+2)
427     return -1;
428   if (!strcasecmp(arg->argv[arg->argn], "slots")) {
429     int slots;
430 
431     slots = atoi(arg->argv[arg->argn+1]);
432     if (slots < 4 || slots > 16)
433       return 1;
434     arg->bundle->ncp.ipcp.cfg.vj.slots = slots;
435     return 0;
436   } else if (!strcasecmp(arg->argv[arg->argn], "slotcomp")) {
437     if (!strcasecmp(arg->argv[arg->argn+1], "on"))
438       arg->bundle->ncp.ipcp.cfg.vj.slotcomp = 1;
439     else if (!strcasecmp(arg->argv[arg->argn+1], "off"))
440       arg->bundle->ncp.ipcp.cfg.vj.slotcomp = 0;
441     else
442       return 2;
443     return 0;
444   }
445   return -1;
446 }
447 
448 void
449 ipcp_Init(struct ipcp *ipcp, struct bundle *bundle, struct link *l,
450           const struct fsm_parent *parent)
451 {
452   struct hostent *hp;
453   struct in_addr host;
454   char name[MAXHOSTNAMELEN];
455   static const char * const timer_names[] =
456     {"IPCP restart", "IPCP openmode", "IPCP stopped"};
457 
458   fsm_Init(&ipcp->fsm, "IPCP", PROTO_IPCP, 1, IPCP_MAXCODE, LogIPCP,
459            bundle, l, parent, &ipcp_Callbacks, timer_names);
460 
461   ipcp->cfg.vj.slots = DEF_VJ_STATES;
462   ipcp->cfg.vj.slotcomp = 1;
463   memset(&ipcp->cfg.my_range, '\0', sizeof ipcp->cfg.my_range);
464 
465   host.s_addr = htonl(INADDR_LOOPBACK);
466   ipcp->cfg.netmask.s_addr = INADDR_ANY;
467   if (gethostname(name, sizeof name) == 0) {
468     hp = gethostbyname(name);
469     if (hp && hp->h_addrtype == AF_INET && hp->h_length == sizeof host.s_addr)
470       memcpy(&host.s_addr, hp->h_addr, sizeof host.s_addr);
471   }
472   ncprange_setip4(&ipcp->cfg.my_range, host, ipcp->cfg.netmask);
473   ncprange_setip4(&ipcp->cfg.peer_range, ipcp->cfg.netmask, ipcp->cfg.netmask);
474 
475   iplist_setsrc(&ipcp->cfg.peer_list, "");
476   ipcp->cfg.HaveTriggerAddress = 0;
477 
478   ipcp->cfg.ns.dns[0].s_addr = INADDR_NONE;
479   ipcp->cfg.ns.dns[1].s_addr = INADDR_NONE;
480   ipcp->cfg.ns.dns_neg = 0;
481   ipcp->cfg.ns.nbns[0].s_addr = INADDR_ANY;
482   ipcp->cfg.ns.nbns[1].s_addr = INADDR_ANY;
483 
484   ipcp->cfg.fsm.timeout = DEF_FSMRETRY;
485   ipcp->cfg.fsm.maxreq = DEF_FSMTRIES;
486   ipcp->cfg.fsm.maxtrm = DEF_FSMTRIES;
487   ipcp->cfg.vj.neg = NEG_ENABLED|NEG_ACCEPTED;
488 
489   memset(&ipcp->vj, '\0', sizeof ipcp->vj);
490 
491   ipcp->ns.resolv = NULL;
492   ipcp->ns.resolv_nons = NULL;
493   ipcp->ns.writable = 1;
494   ipcp_LoadDNS(ipcp);
495 
496   throughput_init(&ipcp->throughput, SAMPLE_PERIOD);
497   memset(ipcp->Queue, '\0', sizeof ipcp->Queue);
498   ipcp_Setup(ipcp, INADDR_NONE);
499 }
500 
501 void
502 ipcp_Destroy(struct ipcp *ipcp)
503 {
504   throughput_destroy(&ipcp->throughput);
505 
506   if (ipcp->ns.resolv != NULL) {
507     free(ipcp->ns.resolv);
508     ipcp->ns.resolv = NULL;
509   }
510   if (ipcp->ns.resolv_nons != NULL) {
511     free(ipcp->ns.resolv_nons);
512     ipcp->ns.resolv_nons = NULL;
513   }
514 }
515 
516 void
517 ipcp_SetLink(struct ipcp *ipcp, struct link *l)
518 {
519   ipcp->fsm.link = l;
520 }
521 
522 void
523 ipcp_Setup(struct ipcp *ipcp, u_int32_t mask)
524 {
525   struct iface *iface = ipcp->fsm.bundle->iface;
526   struct ncpaddr ipaddr;
527   struct in_addr peer;
528   int pos;
529   unsigned n;
530 
531   ipcp->fsm.open_mode = 0;
532   ipcp->ifmask.s_addr = mask == INADDR_NONE ? ipcp->cfg.netmask.s_addr : mask;
533 
534   if (iplist_isvalid(&ipcp->cfg.peer_list)) {
535     /* Try to give the peer a previously configured IP address */
536     for (n = 0; n < iface->addrs; n++) {
537       if (!ncpaddr_getip4(&iface->addr[n].peer, &peer))
538         continue;
539       if ((pos = iplist_ip2pos(&ipcp->cfg.peer_list, peer)) != -1) {
540         ncpaddr_setip4(&ipaddr, iplist_setcurpos(&ipcp->cfg.peer_list, pos));
541         break;
542       }
543     }
544     if (n == iface->addrs)
545       /* Ok, so none of 'em fit.... pick a random one */
546       ncpaddr_setip4(&ipaddr, iplist_setrandpos(&ipcp->cfg.peer_list));
547 
548     ncprange_sethost(&ipcp->cfg.peer_range, &ipaddr);
549   }
550 
551   ipcp->heis1172 = 0;
552   ipcp->peer_req = 0;
553   ncprange_getip4addr(&ipcp->cfg.peer_range, &ipcp->peer_ip);
554   ipcp->peer_compproto = 0;
555 
556   if (ipcp->cfg.HaveTriggerAddress) {
557     /*
558      * Some implementations of PPP require that we send a
559      * *special* value as our address, even though the rfc specifies
560      * full negotiation (e.g. "0.0.0.0" or Not "0.0.0.0").
561      */
562     ipcp->my_ip = ipcp->cfg.TriggerAddress;
563     log_Printf(LogIPCP, "Using trigger address %s\n",
564               inet_ntoa(ipcp->cfg.TriggerAddress));
565   } else {
566     /*
567      * Otherwise, if we've used an IP number before and it's still within
568      * the network specified on the ``set ifaddr'' line, we really
569      * want to keep that IP number so that we can keep any existing
570      * connections that are bound to that IP.
571      */
572     for (n = 0; n < iface->addrs; n++) {
573       ncprange_getaddr(&iface->addr[n].ifa, &ipaddr);
574       if (ncprange_contains(&ipcp->cfg.my_range, &ipaddr)) {
575         ncpaddr_getip4(&ipaddr, &ipcp->my_ip);
576         break;
577       }
578     }
579     if (n == iface->addrs)
580       ncprange_getip4addr(&ipcp->cfg.my_range, &ipcp->my_ip);
581   }
582 
583   if (IsEnabled(ipcp->cfg.vj.neg)
584 #ifndef NORADIUS
585       || (ipcp->fsm.bundle->radius.valid && ipcp->fsm.bundle->radius.vj)
586 #endif
587      )
588     ipcp->my_compproto = (PROTO_VJCOMP << 16) +
589                          ((ipcp->cfg.vj.slots - 1) << 8) +
590                          ipcp->cfg.vj.slotcomp;
591   else
592     ipcp->my_compproto = 0;
593   sl_compress_init(&ipcp->vj.cslc, ipcp->cfg.vj.slots - 1);
594 
595   ipcp->peer_reject = 0;
596   ipcp->my_reject = 0;
597 
598   /* Copy startup values into ipcp->ns.dns */
599   if (ipcp->cfg.ns.dns[0].s_addr != INADDR_NONE)
600     memcpy(ipcp->ns.dns, ipcp->cfg.ns.dns, sizeof ipcp->ns.dns);
601 }
602 
603 static int
604 numaddresses(struct in_addr mask)
605 {
606   u_int32_t bit, haddr;
607   int n;
608 
609   haddr = ntohl(mask.s_addr);
610   bit = 1;
611   n = 1;
612 
613   do {
614     if (!(haddr & bit))
615       n <<= 1;
616   } while (bit <<= 1);
617 
618   return n;
619 }
620 
621 static int
622 ipcp_proxyarp(struct ipcp *ipcp,
623               int (*proxyfun)(struct bundle *, struct in_addr),
624               const struct iface_addr *addr)
625 {
626   struct bundle *bundle = ipcp->fsm.bundle;
627   struct in_addr peer, mask, ip;
628   int n, ret;
629 
630   if (!ncpaddr_getip4(&addr->peer, &peer)) {
631     log_Printf(LogERROR, "Oops, ipcp_proxyarp() called with unexpected addr\n");
632     return 0;
633   }
634 
635   ret = 0;
636 
637   if (Enabled(bundle, OPT_PROXYALL)) {
638     ncprange_getip4mask(&addr->ifa, &mask);
639     if ((n = numaddresses(mask)) > 256) {
640       log_Printf(LogWARN, "%s: Too many addresses for proxyall\n",
641                  ncprange_ntoa(&addr->ifa));
642       return 0;
643     }
644     ip.s_addr = peer.s_addr & mask.s_addr;
645     if (n >= 4) {
646       ip.s_addr = htonl(ntohl(ip.s_addr) + 1);
647       n -= 2;
648     }
649     while (n) {
650       if (!((ip.s_addr ^ peer.s_addr) & mask.s_addr)) {
651         if (!(ret = (*proxyfun)(bundle, ip)))
652           break;
653         n--;
654       }
655       ip.s_addr = htonl(ntohl(ip.s_addr) + 1);
656     }
657     ret = !n;
658   } else if (Enabled(bundle, OPT_PROXY))
659     ret = (*proxyfun)(bundle, peer);
660 
661   return ret;
662 }
663 
664 static int
665 ipcp_SetIPaddress(struct ipcp *ipcp, struct in_addr myaddr,
666                   struct in_addr hisaddr)
667 {
668   struct bundle *bundle = ipcp->fsm.bundle;
669   struct ncpaddr myncpaddr, hisncpaddr;
670   struct ncprange myrange;
671   struct in_addr mask;
672   struct sockaddr_storage ssdst, ssgw, ssmask;
673   struct sockaddr *sadst, *sagw, *samask;
674 
675   sadst = (struct sockaddr *)&ssdst;
676   sagw = (struct sockaddr *)&ssgw;
677   samask = (struct sockaddr *)&ssmask;
678 
679   ncpaddr_setip4(&hisncpaddr, hisaddr);
680   ncpaddr_setip4(&myncpaddr, myaddr);
681   ncprange_sethost(&myrange, &myncpaddr);
682 
683   mask = addr2mask(myaddr);
684 
685   if (ipcp->ifmask.s_addr != INADDR_ANY &&
686       (ipcp->ifmask.s_addr & mask.s_addr) == mask.s_addr)
687     ncprange_setip4mask(&myrange, ipcp->ifmask);
688 
689   if (!iface_Add(bundle->iface, &bundle->ncp, &myrange, &hisncpaddr,
690                  IFACE_ADD_FIRST|IFACE_FORCE_ADD|IFACE_SYSTEM))
691     return 0;
692 
693   if (!Enabled(bundle, OPT_IFACEALIAS))
694     iface_Clear(bundle->iface, &bundle->ncp, AF_INET,
695                 IFACE_CLEAR_ALIASES|IFACE_SYSTEM);
696 
697   if (bundle->ncp.cfg.sendpipe > 0 || bundle->ncp.cfg.recvpipe > 0) {
698     ncprange_getsa(&myrange, &ssgw, &ssmask);
699     ncpaddr_getsa(&hisncpaddr, &ssdst);
700     rt_Update(bundle, sadst, sagw, samask, NULL, NULL);
701   }
702 
703   if (Enabled(bundle, OPT_SROUTES))
704     route_Change(bundle, bundle->ncp.route, &myncpaddr, &hisncpaddr);
705 
706 #ifndef NORADIUS
707   if (bundle->radius.valid)
708     route_Change(bundle, bundle->radius.routes, &myncpaddr, &hisncpaddr);
709 #endif
710 
711   return 1;	/* Ok */
712 }
713 
714 static struct in_addr
715 ChooseHisAddr(struct bundle *bundle, struct in_addr gw)
716 {
717   struct in_addr try;
718   u_long f;
719 
720   for (f = 0; f < bundle->ncp.ipcp.cfg.peer_list.nItems; f++) {
721     try = iplist_next(&bundle->ncp.ipcp.cfg.peer_list);
722     log_Printf(LogDEBUG, "ChooseHisAddr: Check item %ld (%s)\n",
723               f, inet_ntoa(try));
724     if (ipcp_SetIPaddress(&bundle->ncp.ipcp, gw, try)) {
725       log_Printf(LogIPCP, "Selected IP address %s\n", inet_ntoa(try));
726       break;
727     }
728   }
729 
730   if (f == bundle->ncp.ipcp.cfg.peer_list.nItems) {
731     log_Printf(LogDEBUG, "ChooseHisAddr: All addresses in use !\n");
732     try.s_addr = INADDR_ANY;
733   }
734 
735   return try;
736 }
737 
738 static void
739 IpcpInitRestartCounter(struct fsm *fp, int what)
740 {
741   /* Set fsm timer load */
742   struct ipcp *ipcp = fsm2ipcp(fp);
743 
744   fp->FsmTimer.load = ipcp->cfg.fsm.timeout * SECTICKS;
745   switch (what) {
746     case FSM_REQ_TIMER:
747       fp->restart = ipcp->cfg.fsm.maxreq;
748       break;
749     case FSM_TRM_TIMER:
750       fp->restart = ipcp->cfg.fsm.maxtrm;
751       break;
752     default:
753       fp->restart = 1;
754       break;
755   }
756 }
757 
758 static void
759 IpcpSendConfigReq(struct fsm *fp)
760 {
761   /* Send config REQ please */
762   struct physical *p = link2physical(fp->link);
763   struct ipcp *ipcp = fsm2ipcp(fp);
764   u_char buff[MAX_FSM_OPT_LEN];
765   struct fsm_opt *o;
766 
767   o = (struct fsm_opt *)buff;
768 
769   if ((p && !physical_IsSync(p)) || !REJECTED(ipcp, TY_IPADDR)) {
770     memcpy(o->data, &ipcp->my_ip.s_addr, 4);
771     INC_FSM_OPT(TY_IPADDR, 6, o);
772   }
773 
774   if (ipcp->my_compproto && !REJECTED(ipcp, TY_COMPPROTO)) {
775     if (ipcp->heis1172) {
776       u_int16_t proto = PROTO_VJCOMP;
777 
778       ua_htons(&proto, o->data);
779       INC_FSM_OPT(TY_COMPPROTO, 4, o);
780     } else {
781       struct compreq req;
782 
783       req.proto = htons(ipcp->my_compproto >> 16);
784       req.slots = (ipcp->my_compproto >> 8) & 255;
785       req.compcid = ipcp->my_compproto & 1;
786       memcpy(o->data, &req, 4);
787       INC_FSM_OPT(TY_COMPPROTO, 6, o);
788     }
789   }
790 
791   if (IsEnabled(ipcp->cfg.ns.dns_neg)) {
792     if (!REJECTED(ipcp, TY_PRIMARY_DNS - TY_ADJUST_NS)) {
793       memcpy(o->data, &ipcp->ns.dns[0].s_addr, 4);
794       INC_FSM_OPT(TY_PRIMARY_DNS, 6, o);
795     }
796 
797     if (!REJECTED(ipcp, TY_SECONDARY_DNS - TY_ADJUST_NS)) {
798       memcpy(o->data, &ipcp->ns.dns[1].s_addr, 4);
799       INC_FSM_OPT(TY_SECONDARY_DNS, 6, o);
800     }
801   }
802 
803   fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, (u_char *)o - buff,
804              MB_IPCPOUT);
805 }
806 
807 static void
808 IpcpSentTerminateReq(struct fsm *fp __unused)
809 {
810   /* Term REQ just sent by FSM */
811 }
812 
813 static void
814 IpcpSendTerminateAck(struct fsm *fp, u_char id)
815 {
816   /* Send Term ACK please */
817   fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_IPCPOUT);
818 }
819 
820 static void
821 IpcpLayerStart(struct fsm *fp)
822 {
823   /* We're about to start up ! */
824   struct ipcp *ipcp = fsm2ipcp(fp);
825 
826   log_Printf(LogIPCP, "%s: LayerStart.\n", fp->link->name);
827   throughput_start(&ipcp->throughput, "IPCP throughput",
828                    Enabled(fp->bundle, OPT_THROUGHPUT));
829   fp->more.reqs = fp->more.naks = fp->more.rejs = ipcp->cfg.fsm.maxreq * 3;
830   ipcp->peer_req = 0;
831 }
832 
833 static void
834 IpcpLayerFinish(struct fsm *fp)
835 {
836   /* We're now down */
837   struct ipcp *ipcp = fsm2ipcp(fp);
838 
839   log_Printf(LogIPCP, "%s: LayerFinish.\n", fp->link->name);
840   throughput_stop(&ipcp->throughput);
841   throughput_log(&ipcp->throughput, LogIPCP, NULL);
842 }
843 
844 /*
845  * Called from iface_Add() via ncp_IfaceAddrAdded()
846  */
847 void
848 ipcp_IfaceAddrAdded(struct ipcp *ipcp, const struct iface_addr *addr)
849 {
850   struct bundle *bundle = ipcp->fsm.bundle;
851 
852   if (Enabled(bundle, OPT_PROXY) || Enabled(bundle, OPT_PROXYALL))
853     ipcp_proxyarp(ipcp, arp_SetProxy, addr);
854 }
855 
856 /*
857  * Called from iface_Clear() and iface_Delete() via ncp_IfaceAddrDeleted()
858  */
859 void
860 ipcp_IfaceAddrDeleted(struct ipcp *ipcp, const struct iface_addr *addr)
861 {
862   struct bundle *bundle = ipcp->fsm.bundle;
863 
864   if (Enabled(bundle, OPT_PROXY) || Enabled(bundle, OPT_PROXYALL))
865     ipcp_proxyarp(ipcp, arp_ClearProxy, addr);
866 }
867 
868 static void
869 IpcpLayerDown(struct fsm *fp)
870 {
871   /* About to come down */
872   struct ipcp *ipcp = fsm2ipcp(fp);
873   static int recursing;
874   char addr[16];
875 
876   if (!recursing++) {
877     snprintf(addr, sizeof addr, "%s", inet_ntoa(ipcp->my_ip));
878     log_Printf(LogIPCP, "%s: LayerDown: %s\n", fp->link->name, addr);
879 
880 #ifndef NORADIUS
881     radius_Flush(&fp->bundle->radius);
882     radius_Account(&fp->bundle->radius, &fp->bundle->radacct,
883                    fp->bundle->links, RAD_STOP, &ipcp->throughput);
884 
885     if (*fp->bundle->radius.cfg.file && fp->bundle->radius.filterid)
886       system_Select(fp->bundle, fp->bundle->radius.filterid, LINKDOWNFILE,
887                     NULL, NULL);
888     radius_StopTimer(&fp->bundle->radius);
889 #endif
890 
891     /*
892      * XXX this stuff should really live in the FSM.  Our config should
893      * associate executable sections in files with events.
894      */
895     if (system_Select(fp->bundle, addr, LINKDOWNFILE, NULL, NULL) < 0) {
896       if (bundle_GetLabel(fp->bundle)) {
897          if (system_Select(fp->bundle, bundle_GetLabel(fp->bundle),
898                           LINKDOWNFILE, NULL, NULL) < 0)
899          system_Select(fp->bundle, "MYADDR", LINKDOWNFILE, NULL, NULL);
900       } else
901         system_Select(fp->bundle, "MYADDR", LINKDOWNFILE, NULL, NULL);
902     }
903 
904     ipcp_Setup(ipcp, INADDR_NONE);
905   }
906   recursing--;
907 }
908 
909 int
910 ipcp_InterfaceUp(struct ipcp *ipcp)
911 {
912   if (!ipcp_SetIPaddress(ipcp, ipcp->my_ip, ipcp->peer_ip)) {
913     log_Printf(LogERROR, "ipcp_InterfaceUp: unable to set ip address\n");
914     return 0;
915   }
916 
917   if (!iface_SetFlags(ipcp->fsm.bundle->iface->name, IFF_UP)) {
918     log_Printf(LogERROR, "ipcp_InterfaceUp: Can't set the IFF_UP flag on %s\n",
919                ipcp->fsm.bundle->iface->name);
920     return 0;
921   }
922 
923 #ifndef NONAT
924   if (ipcp->fsm.bundle->NatEnabled)
925     LibAliasSetAddress(la, ipcp->my_ip);
926 #endif
927 
928   return 1;
929 }
930 
931 static int
932 IpcpLayerUp(struct fsm *fp)
933 {
934   /* We're now up */
935   struct ipcp *ipcp = fsm2ipcp(fp);
936   char tbuff[16];
937 
938   log_Printf(LogIPCP, "%s: LayerUp.\n", fp->link->name);
939   snprintf(tbuff, sizeof tbuff, "%s", inet_ntoa(ipcp->my_ip));
940   log_Printf(LogIPCP, "myaddr %s hisaddr = %s\n",
941              tbuff, inet_ntoa(ipcp->peer_ip));
942 
943   if (ipcp->peer_compproto >> 16 == PROTO_VJCOMP)
944     sl_compress_init(&ipcp->vj.cslc, (ipcp->peer_compproto >> 8) & 255);
945 
946   if (!ipcp_InterfaceUp(ipcp))
947     return 0;
948 
949 #ifndef NORADIUS
950   radius_Account_Set_Ip(&fp->bundle->radacct, &ipcp->peer_ip, &ipcp->ifmask);
951   radius_Account(&fp->bundle->radius, &fp->bundle->radacct, fp->bundle->links,
952                  RAD_START, &ipcp->throughput);
953 
954   if (*fp->bundle->radius.cfg.file && fp->bundle->radius.filterid)
955     system_Select(fp->bundle, fp->bundle->radius.filterid, LINKUPFILE,
956                   NULL, NULL);
957   radius_StartTimer(fp->bundle);
958 #endif
959 
960   /*
961    * XXX this stuff should really live in the FSM.  Our config should
962    * associate executable sections in files with events.
963    */
964   if (system_Select(fp->bundle, tbuff, LINKUPFILE, NULL, NULL) < 0) {
965     if (bundle_GetLabel(fp->bundle)) {
966       if (system_Select(fp->bundle, bundle_GetLabel(fp->bundle),
967                        LINKUPFILE, NULL, NULL) < 0)
968         system_Select(fp->bundle, "MYADDR", LINKUPFILE, NULL, NULL);
969     } else
970       system_Select(fp->bundle, "MYADDR", LINKUPFILE, NULL, NULL);
971   }
972 
973   fp->more.reqs = fp->more.naks = fp->more.rejs = ipcp->cfg.fsm.maxreq * 3;
974   log_DisplayPrompts();
975 
976   return 1;
977 }
978 
979 static void
980 ipcp_ValidateReq(struct ipcp *ipcp, struct in_addr ip, struct fsm_decode *dec)
981 {
982   struct bundle *bundle = ipcp->fsm.bundle;
983   struct iface *iface = bundle->iface;
984   struct in_addr myaddr, peer;
985   unsigned n;
986 
987   if (iplist_isvalid(&ipcp->cfg.peer_list)) {
988     ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
989     if (ip.s_addr == INADDR_ANY ||
990         iplist_ip2pos(&ipcp->cfg.peer_list, ip) < 0 ||
991         !ipcp_SetIPaddress(ipcp, myaddr, ip)) {
992       log_Printf(LogIPCP, "%s: Address invalid or already in use\n",
993                  inet_ntoa(ip));
994       /*
995        * If we've already had a valid address configured for the peer,
996        * try NAKing with that so that we don't have to upset things
997        * too much.
998        */
999       for (n = 0; n < iface->addrs; n++) {
1000         if (!ncpaddr_getip4(&iface->addr[n].peer, &peer))
1001           continue;
1002         if (iplist_ip2pos(&ipcp->cfg.peer_list, peer) >= 0) {
1003           ipcp->peer_ip = peer;
1004           break;
1005         }
1006       }
1007 
1008       if (n == iface->addrs) {
1009         /* Just pick an IP number from our list */
1010         ipcp->peer_ip = ChooseHisAddr(bundle, myaddr);
1011       }
1012 
1013       if (ipcp->peer_ip.s_addr == INADDR_ANY) {
1014         *dec->rejend++ = TY_IPADDR;
1015         *dec->rejend++ = 6;
1016         memcpy(dec->rejend, &ip.s_addr, 4);
1017         dec->rejend += 4;
1018       } else {
1019         *dec->nakend++ = TY_IPADDR;
1020         *dec->nakend++ = 6;
1021         memcpy(dec->nakend, &ipcp->peer_ip.s_addr, 4);
1022         dec->nakend += 4;
1023       }
1024       return;
1025     }
1026   } else if (ip.s_addr == INADDR_ANY ||
1027              !ncprange_containsip4(&ipcp->cfg.peer_range, ip)) {
1028     /*
1029      * If the destination address is not acceptable, NAK with what we
1030      * want to use.
1031      */
1032     *dec->nakend++ = TY_IPADDR;
1033     *dec->nakend++ = 6;
1034     for (n = 0; n < iface->addrs; n++)
1035       if (ncprange_contains(&ipcp->cfg.peer_range, &iface->addr[n].peer)) {
1036         /* We prefer the already-configured address */
1037         ncpaddr_getip4addr(&iface->addr[n].peer, (u_int32_t *)dec->nakend);
1038         break;
1039       }
1040 
1041     if (n == iface->addrs)
1042       memcpy(dec->nakend, &ipcp->peer_ip.s_addr, 4);
1043 
1044     dec->nakend += 4;
1045     return;
1046   }
1047 
1048   ipcp->peer_ip = ip;
1049   *dec->ackend++ = TY_IPADDR;
1050   *dec->ackend++ = 6;
1051   memcpy(dec->ackend, &ip.s_addr, 4);
1052   dec->ackend += 4;
1053 }
1054 
1055 static void
1056 IpcpDecodeConfig(struct fsm *fp, u_char *cp, u_char *end, int mode_type,
1057                  struct fsm_decode *dec)
1058 {
1059   /* Deal with incoming PROTO_IPCP */
1060   struct ncpaddr ncpaddr;
1061   struct ipcp *ipcp = fsm2ipcp(fp);
1062   int gotdnsnak;
1063   u_int32_t compproto;
1064   struct compreq pcomp;
1065   struct in_addr ipaddr, dstipaddr, have_ip;
1066   char tbuff[100], tbuff2[100];
1067   struct fsm_opt *opt, nak;
1068 
1069   gotdnsnak = 0;
1070 
1071   while (end - cp >= (int)sizeof(opt->hdr)) {
1072     if ((opt = fsm_readopt(&cp)) == NULL)
1073       break;
1074 
1075     snprintf(tbuff, sizeof tbuff, " %s[%d]", protoname(opt->hdr.id),
1076              opt->hdr.len);
1077 
1078     switch (opt->hdr.id) {
1079     case TY_IPADDR:		/* RFC1332 */
1080       memcpy(&ipaddr.s_addr, opt->data, 4);
1081       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1082 
1083       switch (mode_type) {
1084       case MODE_REQ:
1085         ipcp->peer_req = 1;
1086         ipcp_ValidateReq(ipcp, ipaddr, dec);
1087         break;
1088 
1089       case MODE_NAK:
1090         if (ncprange_containsip4(&ipcp->cfg.my_range, ipaddr)) {
1091           /* Use address suggested by peer */
1092           snprintf(tbuff2, sizeof tbuff2, "%s changing address: %s ", tbuff,
1093                    inet_ntoa(ipcp->my_ip));
1094           log_Printf(LogIPCP, "%s --> %s\n", tbuff2, inet_ntoa(ipaddr));
1095           ipcp->my_ip = ipaddr;
1096           ncpaddr_setip4(&ncpaddr, ipcp->my_ip);
1097           bundle_AdjustFilters(fp->bundle, &ncpaddr, NULL);
1098         } else {
1099           log_Printf(log_IsKept(LogIPCP) ? LogIPCP : LogPHASE,
1100                     "%s: Unacceptable address!\n", inet_ntoa(ipaddr));
1101           fsm_Close(&ipcp->fsm);
1102         }
1103         break;
1104 
1105       case MODE_REJ:
1106         ipcp->peer_reject |= (1 << opt->hdr.id);
1107         break;
1108       }
1109       break;
1110 
1111     case TY_COMPPROTO:
1112       memcpy(&pcomp, opt->data, sizeof pcomp);
1113       compproto = (ntohs(pcomp.proto) << 16) + ((int)pcomp.slots << 8) +
1114                   pcomp.compcid;
1115       log_Printf(LogIPCP, "%s %s\n", tbuff, vj2asc(compproto));
1116 
1117       switch (mode_type) {
1118       case MODE_REQ:
1119         if (!IsAccepted(ipcp->cfg.vj.neg))
1120           fsm_rej(dec, opt);
1121         else {
1122           switch (opt->hdr.len) {
1123           case 4:		/* RFC1172 */
1124             if (ntohs(pcomp.proto) == PROTO_VJCOMP) {
1125               log_Printf(LogWARN, "Peer is speaking RFC1172 compression "
1126                          "protocol !\n");
1127               ipcp->heis1172 = 1;
1128               ipcp->peer_compproto = compproto;
1129               fsm_ack(dec, opt);
1130             } else {
1131               pcomp.proto = htons(PROTO_VJCOMP);
1132               nak.hdr.id = TY_COMPPROTO;
1133               nak.hdr.len = 4;
1134               memcpy(nak.data, &pcomp, 2);
1135               fsm_nak(dec, &nak);
1136             }
1137             break;
1138           case 6:		/* RFC1332 */
1139             if (ntohs(pcomp.proto) == PROTO_VJCOMP) {
1140 	      /* We know pcomp.slots' max value == MAX_VJ_STATES */
1141               if (pcomp.slots >= MIN_VJ_STATES) {
1142                 /* Ok, we can do that */
1143                 ipcp->peer_compproto = compproto;
1144                 ipcp->heis1172 = 0;
1145                 fsm_ack(dec, opt);
1146               } else {
1147                 /* Get as close as we can to what he wants */
1148                 ipcp->heis1172 = 0;
1149                 pcomp.slots = MIN_VJ_STATES;
1150                 nak.hdr.id = TY_COMPPROTO;
1151                 nak.hdr.len = 4;
1152                 memcpy(nak.data, &pcomp, 2);
1153                 fsm_nak(dec, &nak);
1154               }
1155             } else {
1156               /* What we really want */
1157               pcomp.proto = htons(PROTO_VJCOMP);
1158               pcomp.slots = DEF_VJ_STATES;
1159               pcomp.compcid = 1;
1160               nak.hdr.id = TY_COMPPROTO;
1161               nak.hdr.len = 6;
1162               memcpy(nak.data, &pcomp, sizeof pcomp);
1163               fsm_nak(dec, &nak);
1164             }
1165             break;
1166           default:
1167             fsm_rej(dec, opt);
1168             break;
1169           }
1170         }
1171         break;
1172 
1173       case MODE_NAK:
1174         if (ntohs(pcomp.proto) == PROTO_VJCOMP) {
1175 	  /* We know pcomp.slots' max value == MAX_VJ_STATES */
1176           if (pcomp.slots < MIN_VJ_STATES)
1177             pcomp.slots = MIN_VJ_STATES;
1178           compproto = (ntohs(pcomp.proto) << 16) + (pcomp.slots << 8) +
1179                       pcomp.compcid;
1180         } else
1181           compproto = 0;
1182         log_Printf(LogIPCP, "%s changing compproto: %08x --> %08x\n",
1183                    tbuff, ipcp->my_compproto, compproto);
1184         ipcp->my_compproto = compproto;
1185         break;
1186 
1187       case MODE_REJ:
1188         ipcp->peer_reject |= (1 << opt->hdr.id);
1189         break;
1190       }
1191       break;
1192 
1193     case TY_IPADDRS:		/* RFC1172 */
1194       memcpy(&ipaddr.s_addr, opt->data, 4);
1195       memcpy(&dstipaddr.s_addr, opt->data + 4, 4);
1196       snprintf(tbuff2, sizeof tbuff2, "%s %s,", tbuff, inet_ntoa(ipaddr));
1197       log_Printf(LogIPCP, "%s %s\n", tbuff2, inet_ntoa(dstipaddr));
1198 
1199       switch (mode_type) {
1200       case MODE_REQ:
1201         fsm_rej(dec, opt);
1202         break;
1203 
1204       case MODE_NAK:
1205       case MODE_REJ:
1206         break;
1207       }
1208       break;
1209 
1210     case TY_PRIMARY_DNS:	/* DNS negotiation (rfc1877) */
1211     case TY_SECONDARY_DNS:
1212       memcpy(&ipaddr.s_addr, opt->data, 4);
1213       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1214 
1215       switch (mode_type) {
1216       case MODE_REQ:
1217         if (!IsAccepted(ipcp->cfg.ns.dns_neg)) {
1218           ipcp->my_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1219           fsm_rej(dec, opt);
1220           break;
1221         }
1222         have_ip = ipcp->ns.dns[opt->hdr.id == TY_PRIMARY_DNS ? 0 : 1];
1223 
1224         if (opt->hdr.id == TY_PRIMARY_DNS && ipaddr.s_addr != have_ip.s_addr &&
1225             ipaddr.s_addr == ipcp->ns.dns[1].s_addr) {
1226           /* Swap 'em 'round */
1227           ipcp->ns.dns[0] = ipcp->ns.dns[1];
1228           ipcp->ns.dns[1] = have_ip;
1229           have_ip = ipcp->ns.dns[0];
1230         }
1231 
1232         if (ipaddr.s_addr != have_ip.s_addr) {
1233           /*
1234            * The client has got the DNS stuff wrong (first request) so
1235            * we'll tell 'em how it is
1236            */
1237           nak.hdr.id = opt->hdr.id;
1238           nak.hdr.len = 6;
1239           memcpy(nak.data, &have_ip.s_addr, 4);
1240           fsm_nak(dec, &nak);
1241         } else {
1242           /*
1243            * Otherwise they have it right (this time) so we send an ack packet
1244            * back confirming it... end of story
1245            */
1246           fsm_ack(dec, opt);
1247         }
1248         break;
1249 
1250       case MODE_NAK:
1251         if (IsEnabled(ipcp->cfg.ns.dns_neg)) {
1252           gotdnsnak = 1;
1253           memcpy(&ipcp->ns.dns[opt->hdr.id == TY_PRIMARY_DNS ? 0 : 1].s_addr,
1254                  opt->data, 4);
1255         }
1256         break;
1257 
1258       case MODE_REJ:		/* Can't do much, stop asking */
1259         ipcp->peer_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1260         break;
1261       }
1262       break;
1263 
1264     case TY_PRIMARY_NBNS:	/* M$ NetBIOS nameserver hack (rfc1877) */
1265     case TY_SECONDARY_NBNS:
1266       memcpy(&ipaddr.s_addr, opt->data, 4);
1267       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1268 
1269       switch (mode_type) {
1270       case MODE_REQ:
1271         have_ip.s_addr =
1272           ipcp->cfg.ns.nbns[opt->hdr.id == TY_PRIMARY_NBNS ? 0 : 1].s_addr;
1273 
1274         if (have_ip.s_addr == INADDR_ANY) {
1275           log_Printf(LogIPCP, "NBNS REQ - rejected - nbns not set\n");
1276           ipcp->my_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1277           fsm_rej(dec, opt);
1278           break;
1279         }
1280 
1281         if (ipaddr.s_addr != have_ip.s_addr) {
1282           nak.hdr.id = opt->hdr.id;
1283           nak.hdr.len = 6;
1284           memcpy(nak.data, &have_ip.s_addr, 4);
1285           fsm_nak(dec, &nak);
1286         } else
1287           fsm_ack(dec, opt);
1288         break;
1289 
1290       case MODE_NAK:
1291         log_Printf(LogIPCP, "MS NBNS req %d - NAK??\n", opt->hdr.id);
1292         break;
1293 
1294       case MODE_REJ:
1295         log_Printf(LogIPCP, "MS NBNS req %d - REJ??\n", opt->hdr.id);
1296         break;
1297       }
1298       break;
1299 
1300     default:
1301       if (mode_type != MODE_NOP) {
1302         ipcp->my_reject |= (1 << opt->hdr.id);
1303         fsm_rej(dec, opt);
1304       }
1305       break;
1306     }
1307   }
1308 
1309   if (gotdnsnak) {
1310     if (ipcp->ns.writable) {
1311       log_Printf(LogDEBUG, "Updating resolver\n");
1312       if (!ipcp_WriteDNS(ipcp)) {
1313         ipcp->peer_reject |= (1 << (TY_PRIMARY_DNS - TY_ADJUST_NS));
1314         ipcp->peer_reject |= (1 << (TY_SECONDARY_DNS - TY_ADJUST_NS));
1315       } else
1316         bundle_AdjustDNS(fp->bundle);
1317     } else {
1318       log_Printf(LogDEBUG, "Not updating resolver (readonly)\n");
1319       bundle_AdjustDNS(fp->bundle);
1320     }
1321   }
1322 
1323   if (mode_type != MODE_NOP) {
1324     if (mode_type == MODE_REQ && !ipcp->peer_req) {
1325       if (dec->rejend == dec->rej && dec->nakend == dec->nak) {
1326         /*
1327          * Pretend the peer has requested an IP.
1328          * We do this to ensure that we only send one NAK if the only
1329          * reason for the NAK is because the peer isn't sending a
1330          * TY_IPADDR REQ.  This stops us from repeatedly trying to tell
1331          * the peer that we have to have an IP address on their end.
1332          */
1333         ipcp->peer_req = 1;
1334       }
1335       ipaddr.s_addr = INADDR_ANY;
1336       ipcp_ValidateReq(ipcp, ipaddr, dec);
1337     }
1338     fsm_opt_normalise(dec);
1339   }
1340 }
1341 
1342 extern struct mbuf *
1343 ipcp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
1344 {
1345   /* Got PROTO_IPCP from link */
1346   m_settype(bp, MB_IPCPIN);
1347   if (bundle_Phase(bundle) == PHASE_NETWORK)
1348     fsm_Input(&bundle->ncp.ipcp.fsm, bp);
1349   else {
1350     if (bundle_Phase(bundle) < PHASE_NETWORK)
1351       log_Printf(LogIPCP, "%s: Error: Unexpected IPCP in phase %s (ignored)\n",
1352                  l->name, bundle_PhaseName(bundle));
1353     m_freem(bp);
1354   }
1355   return NULL;
1356 }
1357 
1358 int
1359 ipcp_UseHisIPaddr(struct bundle *bundle, struct in_addr hisaddr)
1360 {
1361   struct ipcp *ipcp = &bundle->ncp.ipcp;
1362   struct in_addr myaddr;
1363 
1364   memset(&ipcp->cfg.peer_range, '\0', sizeof ipcp->cfg.peer_range);
1365   iplist_reset(&ipcp->cfg.peer_list);
1366   ipcp->peer_ip = hisaddr;
1367   ncprange_setip4host(&ipcp->cfg.peer_range, hisaddr);
1368   ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
1369 
1370   return ipcp_SetIPaddress(ipcp, myaddr, hisaddr);
1371 }
1372 
1373 int
1374 ipcp_UseHisaddr(struct bundle *bundle, const char *hisaddr, int setaddr)
1375 {
1376   struct in_addr myaddr;
1377   struct ncp *ncp = &bundle->ncp;
1378   struct ipcp *ipcp = &ncp->ipcp;
1379   struct ncpaddr ncpaddr;
1380 
1381   /* Use `hisaddr' for the peers address (set iface if `setaddr') */
1382   memset(&ipcp->cfg.peer_range, '\0', sizeof ipcp->cfg.peer_range);
1383   iplist_reset(&ipcp->cfg.peer_list);
1384   if (strpbrk(hisaddr, ",-")) {
1385     iplist_setsrc(&ipcp->cfg.peer_list, hisaddr);
1386     if (iplist_isvalid(&ipcp->cfg.peer_list)) {
1387       iplist_setrandpos(&ipcp->cfg.peer_list);
1388       ipcp->peer_ip = ChooseHisAddr(bundle, ipcp->my_ip);
1389       if (ipcp->peer_ip.s_addr == INADDR_ANY) {
1390         log_Printf(LogWARN, "%s: None available !\n", ipcp->cfg.peer_list.src);
1391         return 0;
1392       }
1393       ncprange_setip4host(&ipcp->cfg.peer_range, ipcp->peer_ip);
1394     } else {
1395       log_Printf(LogWARN, "%s: Invalid range !\n", hisaddr);
1396       return 0;
1397     }
1398   } else if (ncprange_aton(&ipcp->cfg.peer_range, ncp, hisaddr) != 0) {
1399     if (ncprange_family(&ipcp->cfg.my_range) != AF_INET) {
1400       log_Printf(LogWARN, "%s: Not an AF_INET address !\n", hisaddr);
1401       return 0;
1402     }
1403     ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
1404     ncprange_getip4addr(&ipcp->cfg.peer_range, &ipcp->peer_ip);
1405 
1406     if (setaddr && !ipcp_SetIPaddress(ipcp, myaddr, ipcp->peer_ip))
1407       return 0;
1408   } else
1409     return 0;
1410 
1411   ncpaddr_setip4(&ncpaddr, ipcp->peer_ip);
1412   bundle_AdjustFilters(bundle, NULL, &ncpaddr);
1413 
1414   return 1;	/* Ok */
1415 }
1416 
1417 struct in_addr
1418 addr2mask(struct in_addr addr)
1419 {
1420   u_int32_t haddr = ntohl(addr.s_addr);
1421 
1422   haddr = IN_CLASSA(haddr) ? IN_CLASSA_NET :
1423           IN_CLASSB(haddr) ? IN_CLASSB_NET :
1424           IN_CLASSC_NET;
1425   addr.s_addr = htonl(haddr);
1426 
1427   return addr;
1428 }
1429 
1430 size_t
1431 ipcp_QueueLen(struct ipcp *ipcp)
1432 {
1433   struct mqueue *q;
1434   size_t result;
1435 
1436   result = 0;
1437   for (q = ipcp->Queue; q < ipcp->Queue + IPCP_QUEUES(ipcp); q++)
1438     result += q->len;
1439 
1440   return result;
1441 }
1442 
1443 int
1444 ipcp_PushPacket(struct ipcp *ipcp, struct link *l)
1445 {
1446   struct bundle *bundle = ipcp->fsm.bundle;
1447   struct mqueue *queue;
1448   struct mbuf *bp;
1449   int m_len;
1450   u_int32_t secs = 0;
1451   unsigned alivesecs = 0;
1452 
1453   if (ipcp->fsm.state != ST_OPENED)
1454     return 0;
1455 
1456   /*
1457    * If ccp is not open but is required, do nothing.
1458    */
1459   if (l->ccp.fsm.state != ST_OPENED && ccp_Required(&l->ccp)) {
1460     log_Printf(LogPHASE, "%s: Not transmitting... waiting for CCP\n", l->name);
1461     return 0;
1462   }
1463 
1464   queue = ipcp->Queue + IPCP_QUEUES(ipcp) - 1;
1465   do {
1466     if (queue->top) {
1467       bp = m_dequeue(queue);
1468       bp = mbuf_Read(bp, &secs, sizeof secs);
1469       bp = m_pullup(bp);
1470       m_len = m_length(bp);
1471       if (!FilterCheck(MBUF_CTOP(bp), AF_INET, &bundle->filter.alive,
1472                        &alivesecs)) {
1473         if (secs == 0)
1474           secs = alivesecs;
1475         bundle_StartIdleTimer(bundle, secs);
1476       }
1477       link_PushPacket(l, bp, bundle, 0, PROTO_IP);
1478       ipcp_AddOutOctets(ipcp, m_len);
1479       return 1;
1480     }
1481   } while (queue-- != ipcp->Queue);
1482 
1483   return 0;
1484 }
1485