xref: /freebsd/usr.sbin/ppp/ipcp.c (revision 8e95079e175854b84e57c521b34b4b52f7ae9cb1)
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 
31 #include <sys/param.h>
32 #include <netinet/in_systm.h>
33 #include <netinet/in.h>
34 #include <netinet/ip.h>
35 #include <arpa/inet.h>
36 #include <sys/socket.h>
37 #include <net/if.h>
38 #include <net/route.h>
39 #include <netdb.h>
40 #include <sys/un.h>
41 
42 #include <errno.h>
43 #include <fcntl.h>
44 #include <resolv.h>
45 #include <stdarg.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <sys/stat.h>
49 #include <termios.h>
50 #include <unistd.h>
51 
52 #ifndef NONAT
53 #ifdef LOCALNAT
54 #include "alias.h"
55 #else
56 #include <alias.h>
57 #endif
58 #endif
59 
60 #include "layer.h"
61 #include "ua.h"
62 #include "defs.h"
63 #include "command.h"
64 #include "mbuf.h"
65 #include "log.h"
66 #include "timer.h"
67 #include "fsm.h"
68 #include "proto.h"
69 #include "iplist.h"
70 #include "throughput.h"
71 #include "slcompress.h"
72 #include "lqr.h"
73 #include "hdlc.h"
74 #include "lcp.h"
75 #include "ncpaddr.h"
76 #include "ip.h"
77 #include "ipcp.h"
78 #include "filter.h"
79 #include "descriptor.h"
80 #include "vjcomp.h"
81 #include "async.h"
82 #include "ccp.h"
83 #include "link.h"
84 #include "physical.h"
85 #include "mp.h"
86 #ifndef NORADIUS
87 #include "radius.h"
88 #endif
89 #include "ipv6cp.h"
90 #include "ncp.h"
91 #include "bundle.h"
92 #include "id.h"
93 #include "arp.h"
94 #include "systems.h"
95 #include "prompt.h"
96 #include "route.h"
97 #include "iface.h"
98 
99 #undef REJECTED
100 #define	REJECTED(p, x)	((p)->peer_reject & (1<<(x)))
101 #define issep(ch) ((ch) == ' ' || (ch) == '\t')
102 #define isip(ch) (((ch) >= '0' && (ch) <= '9') || (ch) == '.')
103 
104 struct compreq {
105   u_short proto;
106   u_char slots;
107   u_char compcid;
108 };
109 
110 static int IpcpLayerUp(struct fsm *);
111 static void IpcpLayerDown(struct fsm *);
112 static void IpcpLayerStart(struct fsm *);
113 static void IpcpLayerFinish(struct fsm *);
114 static void IpcpInitRestartCounter(struct fsm *, int);
115 static void IpcpSendConfigReq(struct fsm *);
116 static void IpcpSentTerminateReq(struct fsm *);
117 static void IpcpSendTerminateAck(struct fsm *, u_char);
118 static void IpcpDecodeConfig(struct fsm *, u_char *, u_char *, int,
119                              struct fsm_decode *);
120 
121 extern struct libalias *la;
122 
123 static struct fsm_callbacks ipcp_Callbacks = {
124   IpcpLayerUp,
125   IpcpLayerDown,
126   IpcpLayerStart,
127   IpcpLayerFinish,
128   IpcpInitRestartCounter,
129   IpcpSendConfigReq,
130   IpcpSentTerminateReq,
131   IpcpSendTerminateAck,
132   IpcpDecodeConfig,
133   fsm_NullRecvResetReq,
134   fsm_NullRecvResetAck
135 };
136 
137 static const char *
138 protoname(int proto)
139 {
140   static struct {
141     int id;
142     const char *txt;
143   } cftypes[] = {
144     /* Check out the latest ``Assigned numbers'' rfc (rfc1700.txt) */
145     { 1, "IPADDRS" },		/* IP-Addresses */	/* deprecated */
146     { 2, "COMPPROTO" },		/* IP-Compression-Protocol */
147     { 3, "IPADDR" },		/* IP-Address */
148     { 129, "PRIDNS" },		/* 129: Primary DNS Server Address */
149     { 130, "PRINBNS" },		/* 130: Primary NBNS Server Address */
150     { 131, "SECDNS" },		/* 131: Secondary DNS Server Address */
151     { 132, "SECNBNS" }		/* 132: Secondary NBNS Server Address */
152   };
153   unsigned f;
154 
155   for (f = 0; f < sizeof cftypes / sizeof *cftypes; f++)
156     if (cftypes[f].id == proto)
157       return cftypes[f].txt;
158 
159   return NumStr(proto, NULL, 0);
160 }
161 
162 void
163 ipcp_AddInOctets(struct ipcp *ipcp, int n)
164 {
165   throughput_addin(&ipcp->throughput, n);
166 }
167 
168 void
169 ipcp_AddOutOctets(struct ipcp *ipcp, int n)
170 {
171   throughput_addout(&ipcp->throughput, n);
172 }
173 
174 void
175 ipcp_LoadDNS(struct ipcp *ipcp)
176 {
177   int fd;
178 
179   ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr = INADDR_NONE;
180 
181   if (ipcp->ns.resolv != NULL) {
182     free(ipcp->ns.resolv);
183     ipcp->ns.resolv = NULL;
184   }
185   if (ipcp->ns.resolv_nons != NULL) {
186     free(ipcp->ns.resolv_nons);
187     ipcp->ns.resolv_nons = NULL;
188   }
189   ipcp->ns.resolver = 0;
190 
191   if ((fd = open(_PATH_RESCONF, O_RDONLY)) != -1) {
192     struct stat st;
193 
194     if (fstat(fd, &st) == 0) {
195       ssize_t got;
196 
197       /*
198        * Note, ns.resolv and ns.resolv_nons are assumed to always point to
199        * buffers of the same size!  See the strcpy() below.
200        */
201       if ((ipcp->ns.resolv_nons = (char *)malloc(st.st_size + 1)) == NULL)
202         log_Printf(LogERROR, "Failed to malloc %lu for %s: %s\n",
203                    (unsigned long)st.st_size, _PATH_RESCONF, strerror(errno));
204       else if ((ipcp->ns.resolv = (char *)malloc(st.st_size + 1)) == NULL) {
205         log_Printf(LogERROR, "Failed(2) to malloc %lu for %s: %s\n",
206                    (unsigned long)st.st_size, _PATH_RESCONF, strerror(errno));
207         free(ipcp->ns.resolv_nons);
208         ipcp->ns.resolv_nons = NULL;
209       } else if ((got = read(fd, ipcp->ns.resolv, st.st_size)) != st.st_size) {
210         if (got == -1)
211           log_Printf(LogERROR, "Failed to read %s: %s\n",
212                      _PATH_RESCONF, strerror(errno));
213         else
214           log_Printf(LogERROR, "Failed to read %s, got %lu not %lu\n",
215                      _PATH_RESCONF, (unsigned long)got,
216                      (unsigned long)st.st_size);
217         free(ipcp->ns.resolv_nons);
218         ipcp->ns.resolv_nons = NULL;
219         free(ipcp->ns.resolv);
220         ipcp->ns.resolv = NULL;
221       } else {
222         char *cp, *cp_nons, *ncp, ch;
223         int n;
224 
225         ipcp->ns.resolv[st.st_size] = '\0';
226         ipcp->ns.resolver = 1;
227 
228         cp_nons = ipcp->ns.resolv_nons;
229         cp = ipcp->ns.resolv;
230         n = 0;
231 
232         while ((ncp = strstr(cp, "nameserver")) != NULL) {
233           if (ncp != cp) {
234             memcpy(cp_nons, cp, ncp - cp);
235             cp_nons += ncp - cp;
236           }
237           if ((ncp != cp && ncp[-1] != '\n') || !issep(ncp[10])) {
238             memcpy(cp_nons, ncp, 9);
239             cp_nons += 9;
240             cp = ncp + 9;	/* Can't match "nameserver" at cp... */
241             continue;
242           }
243 
244           for (cp = ncp + 11; issep(*cp); cp++)	/* Skip whitespace */
245             ;
246 
247           for (ncp = cp; isip(*ncp); ncp++)		/* Jump over IP */
248             ;
249 
250           ch = *ncp;
251           *ncp = '\0';
252           if (n < 2 && inet_aton(cp, ipcp->ns.dns))
253             n++;
254           *ncp = ch;
255 
256           if ((cp = strchr(ncp, '\n')) == NULL)	/* Point at next line */
257             cp = ncp + strlen(ncp);
258           else
259             cp++;
260         }
261         /*
262          * Note, cp_nons and cp always point to buffers of the same size, so
263          * strcpy is ok!
264          */
265         strcpy(cp_nons, cp);	/* Copy the end - including the NUL */
266         cp_nons += strlen(cp_nons) - 1;
267         while (cp_nons >= ipcp->ns.resolv_nons && *cp_nons == '\n')
268           *cp_nons-- = '\0';
269         if (n == 2 && ipcp->ns.dns[0].s_addr == INADDR_ANY) {
270           ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr;
271           ipcp->ns.dns[1].s_addr = INADDR_ANY;
272         }
273         bundle_AdjustDNS(ipcp->fsm.bundle);
274       }
275     } else
276       log_Printf(LogERROR, "Failed to stat opened %s: %s\n",
277                  _PATH_RESCONF, strerror(errno));
278 
279     close(fd);
280   }
281 }
282 
283 int
284 ipcp_WriteDNS(struct ipcp *ipcp)
285 {
286   const char *paddr;
287   mode_t mask;
288   FILE *fp;
289 
290   if (ipcp->ns.dns[0].s_addr == INADDR_ANY &&
291       ipcp->ns.dns[1].s_addr == INADDR_ANY) {
292     log_Printf(LogIPCP, "%s not modified: All nameservers NAKd\n",
293               _PATH_RESCONF);
294     return 0;
295   }
296 
297   if (ipcp->ns.dns[0].s_addr == INADDR_ANY) {
298     ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr;
299     ipcp->ns.dns[1].s_addr = INADDR_ANY;
300   }
301 
302   mask = umask(022);
303   if ((fp = ID0fopen(_PATH_RESCONF, "w")) != NULL) {
304     umask(mask);
305     if (ipcp->ns.resolv_nons)
306       fputs(ipcp->ns.resolv_nons, fp);
307     paddr = inet_ntoa(ipcp->ns.dns[0]);
308     log_Printf(LogIPCP, "Primary nameserver set to %s\n", paddr);
309     fprintf(fp, "\nnameserver %s\n", paddr);
310     if (ipcp->ns.dns[1].s_addr != INADDR_ANY &&
311         ipcp->ns.dns[1].s_addr != INADDR_NONE &&
312         ipcp->ns.dns[1].s_addr != ipcp->ns.dns[0].s_addr) {
313       paddr = inet_ntoa(ipcp->ns.dns[1]);
314       log_Printf(LogIPCP, "Secondary nameserver set to %s\n", paddr);
315       fprintf(fp, "nameserver %s\n", paddr);
316     }
317     if (fclose(fp) == EOF) {
318       log_Printf(LogERROR, "write(): Failed updating %s: %s\n", _PATH_RESCONF,
319                  strerror(errno));
320       return 0;
321     }
322   } else {
323     umask(mask);
324     log_Printf(LogERROR,"fopen(\"%s\", \"w\") failed: %s\n", _PATH_RESCONF,
325                  strerror(errno));
326   }
327 
328   return 1;
329 }
330 
331 void
332 ipcp_RestoreDNS(struct ipcp *ipcp)
333 {
334   if (ipcp->ns.resolver) {
335     ssize_t got, len;
336     int fd;
337 
338     if ((fd = ID0open(_PATH_RESCONF, O_WRONLY|O_TRUNC, 0644)) != -1) {
339       len = strlen(ipcp->ns.resolv);
340       if ((got = write(fd, ipcp->ns.resolv, len)) != len) {
341         if (got == -1)
342           log_Printf(LogERROR, "Failed rewriting %s: write: %s\n",
343                      _PATH_RESCONF, strerror(errno));
344         else
345           log_Printf(LogERROR, "Failed rewriting %s: wrote %ld of %ld\n",
346                      _PATH_RESCONF, (long)got, (long)len);
347       }
348       close(fd);
349     } else
350       log_Printf(LogERROR, "Failed rewriting %s: open: %s\n", _PATH_RESCONF,
351                  strerror(errno));
352   } else if (remove(_PATH_RESCONF) == -1)
353     log_Printf(LogERROR, "Failed removing %s: %s\n", _PATH_RESCONF,
354                strerror(errno));
355 
356 }
357 
358 int
359 ipcp_Show(struct cmdargs const *arg)
360 {
361   struct ipcp *ipcp = &arg->bundle->ncp.ipcp;
362 
363   prompt_Printf(arg->prompt, "%s [%s]\n", ipcp->fsm.name,
364                 State2Nam(ipcp->fsm.state));
365   if (ipcp->fsm.state == ST_OPENED) {
366     prompt_Printf(arg->prompt, " His side:        %s, %s\n",
367                   inet_ntoa(ipcp->peer_ip), vj2asc(ipcp->peer_compproto));
368     prompt_Printf(arg->prompt, " My side:         %s, %s\n",
369                   inet_ntoa(ipcp->my_ip), vj2asc(ipcp->my_compproto));
370     prompt_Printf(arg->prompt, " Queued packets:  %lu\n",
371                   (unsigned long)ipcp_QueueLen(ipcp));
372   }
373 
374   prompt_Printf(arg->prompt, "\nDefaults:\n");
375   prompt_Printf(arg->prompt, " FSM retry = %us, max %u Config"
376                 " REQ%s, %u Term REQ%s\n", ipcp->cfg.fsm.timeout,
377                 ipcp->cfg.fsm.maxreq, ipcp->cfg.fsm.maxreq == 1 ? "" : "s",
378                 ipcp->cfg.fsm.maxtrm, ipcp->cfg.fsm.maxtrm == 1 ? "" : "s");
379   prompt_Printf(arg->prompt, " My Address:      %s\n",
380                 ncprange_ntoa(&ipcp->cfg.my_range));
381   if (ipcp->cfg.HaveTriggerAddress)
382     prompt_Printf(arg->prompt, " Trigger address: %s\n",
383                   inet_ntoa(ipcp->cfg.TriggerAddress));
384 
385   prompt_Printf(arg->prompt, " VJ compression:  %s (%d slots %s slot "
386                 "compression)\n", command_ShowNegval(ipcp->cfg.vj.neg),
387                 ipcp->cfg.vj.slots, ipcp->cfg.vj.slotcomp ? "with" : "without");
388 
389   if (iplist_isvalid(&ipcp->cfg.peer_list))
390     prompt_Printf(arg->prompt, " His Address:     %s\n",
391                   ipcp->cfg.peer_list.src);
392   else
393     prompt_Printf(arg->prompt, " His Address:     %s\n",
394                   ncprange_ntoa(&ipcp->cfg.peer_range));
395 
396   prompt_Printf(arg->prompt, " DNS:             %s",
397                 ipcp->cfg.ns.dns[0].s_addr == INADDR_NONE ?
398                 "none" : inet_ntoa(ipcp->cfg.ns.dns[0]));
399   if (ipcp->cfg.ns.dns[1].s_addr != INADDR_NONE)
400     prompt_Printf(arg->prompt, ", %s",
401                   inet_ntoa(ipcp->cfg.ns.dns[1]));
402   prompt_Printf(arg->prompt, ", %s\n",
403                 command_ShowNegval(ipcp->cfg.ns.dns_neg));
404   prompt_Printf(arg->prompt, " Resolver DNS:    %s",
405                 ipcp->ns.dns[0].s_addr == INADDR_NONE ?
406                 "none" : inet_ntoa(ipcp->ns.dns[0]));
407   if (ipcp->ns.dns[1].s_addr != INADDR_NONE &&
408       ipcp->ns.dns[1].s_addr != ipcp->ns.dns[0].s_addr)
409     prompt_Printf(arg->prompt, ", %s",
410                   inet_ntoa(ipcp->ns.dns[1]));
411   prompt_Printf(arg->prompt, "\n NetBIOS NS:      %s, ",
412                 inet_ntoa(ipcp->cfg.ns.nbns[0]));
413   prompt_Printf(arg->prompt, "%s\n\n",
414                 inet_ntoa(ipcp->cfg.ns.nbns[1]));
415 
416   throughput_disp(&ipcp->throughput, arg->prompt);
417 
418   return 0;
419 }
420 
421 int
422 ipcp_vjset(struct cmdargs const *arg)
423 {
424   if (arg->argc != arg->argn+2)
425     return -1;
426   if (!strcasecmp(arg->argv[arg->argn], "slots")) {
427     int slots;
428 
429     slots = atoi(arg->argv[arg->argn+1]);
430     if (slots < 4 || slots > 16)
431       return 1;
432     arg->bundle->ncp.ipcp.cfg.vj.slots = slots;
433     return 0;
434   } else if (!strcasecmp(arg->argv[arg->argn], "slotcomp")) {
435     if (!strcasecmp(arg->argv[arg->argn+1], "on"))
436       arg->bundle->ncp.ipcp.cfg.vj.slotcomp = 1;
437     else if (!strcasecmp(arg->argv[arg->argn+1], "off"))
438       arg->bundle->ncp.ipcp.cfg.vj.slotcomp = 0;
439     else
440       return 2;
441     return 0;
442   }
443   return -1;
444 }
445 
446 void
447 ipcp_Init(struct ipcp *ipcp, struct bundle *bundle, struct link *l,
448           const struct fsm_parent *parent)
449 {
450   struct hostent *hp;
451   struct in_addr host;
452   char name[MAXHOSTNAMELEN];
453   static const char * const timer_names[] =
454     {"IPCP restart", "IPCP openmode", "IPCP stopped"};
455 
456   fsm_Init(&ipcp->fsm, "IPCP", PROTO_IPCP, 1, IPCP_MAXCODE, LogIPCP,
457            bundle, l, parent, &ipcp_Callbacks, timer_names);
458 
459   ipcp->cfg.vj.slots = DEF_VJ_STATES;
460   ipcp->cfg.vj.slotcomp = 1;
461   memset(&ipcp->cfg.my_range, '\0', sizeof ipcp->cfg.my_range);
462 
463   host.s_addr = htonl(INADDR_LOOPBACK);
464   ipcp->cfg.netmask.s_addr = INADDR_ANY;
465   if (gethostname(name, sizeof name) == 0) {
466     hp = gethostbyname(name);
467     if (hp && hp->h_addrtype == AF_INET && hp->h_length == sizeof host.s_addr)
468       memcpy(&host.s_addr, hp->h_addr, sizeof host.s_addr);
469   }
470   ncprange_setip4(&ipcp->cfg.my_range, host, ipcp->cfg.netmask);
471   ncprange_setip4(&ipcp->cfg.peer_range, ipcp->cfg.netmask, ipcp->cfg.netmask);
472 
473   iplist_setsrc(&ipcp->cfg.peer_list, "");
474   ipcp->cfg.HaveTriggerAddress = 0;
475 
476   ipcp->cfg.ns.dns[0].s_addr = INADDR_NONE;
477   ipcp->cfg.ns.dns[1].s_addr = INADDR_NONE;
478   ipcp->cfg.ns.dns_neg = 0;
479   ipcp->cfg.ns.nbns[0].s_addr = INADDR_ANY;
480   ipcp->cfg.ns.nbns[1].s_addr = INADDR_ANY;
481 
482   ipcp->cfg.fsm.timeout = DEF_FSMRETRY;
483   ipcp->cfg.fsm.maxreq = DEF_FSMTRIES;
484   ipcp->cfg.fsm.maxtrm = DEF_FSMTRIES;
485   ipcp->cfg.vj.neg = NEG_ENABLED|NEG_ACCEPTED;
486 
487   memset(&ipcp->vj, '\0', sizeof ipcp->vj);
488 
489   ipcp->ns.resolv = NULL;
490   ipcp->ns.resolv_nons = NULL;
491   ipcp->ns.writable = 1;
492   ipcp_LoadDNS(ipcp);
493 
494   throughput_init(&ipcp->throughput, SAMPLE_PERIOD);
495   memset(ipcp->Queue, '\0', sizeof ipcp->Queue);
496   ipcp_Setup(ipcp, INADDR_NONE);
497 }
498 
499 void
500 ipcp_Destroy(struct ipcp *ipcp)
501 {
502   throughput_destroy(&ipcp->throughput);
503 
504   if (ipcp->ns.resolv != NULL) {
505     free(ipcp->ns.resolv);
506     ipcp->ns.resolv = NULL;
507   }
508   if (ipcp->ns.resolv_nons != NULL) {
509     free(ipcp->ns.resolv_nons);
510     ipcp->ns.resolv_nons = NULL;
511   }
512 }
513 
514 void
515 ipcp_SetLink(struct ipcp *ipcp, struct link *l)
516 {
517   ipcp->fsm.link = l;
518 }
519 
520 void
521 ipcp_Setup(struct ipcp *ipcp, u_int32_t mask)
522 {
523   struct iface *iface = ipcp->fsm.bundle->iface;
524   struct ncpaddr ipaddr;
525   struct in_addr peer;
526   int pos;
527   unsigned n;
528 
529   ipcp->fsm.open_mode = 0;
530   ipcp->ifmask.s_addr = mask == INADDR_NONE ? ipcp->cfg.netmask.s_addr : mask;
531 
532   if (iplist_isvalid(&ipcp->cfg.peer_list)) {
533     /* Try to give the peer a previously configured IP address */
534     for (n = 0; n < iface->addrs; n++) {
535       if (!ncpaddr_getip4(&iface->addr[n].peer, &peer))
536         continue;
537       if ((pos = iplist_ip2pos(&ipcp->cfg.peer_list, peer)) != -1) {
538         ncpaddr_setip4(&ipaddr, iplist_setcurpos(&ipcp->cfg.peer_list, pos));
539         break;
540       }
541     }
542     if (n == iface->addrs)
543       /* Ok, so none of 'em fit.... pick a random one */
544       ncpaddr_setip4(&ipaddr, iplist_setrandpos(&ipcp->cfg.peer_list));
545 
546     ncprange_sethost(&ipcp->cfg.peer_range, &ipaddr);
547   }
548 
549   ipcp->heis1172 = 0;
550   ipcp->peer_req = 0;
551   ncprange_getip4addr(&ipcp->cfg.peer_range, &ipcp->peer_ip);
552   ipcp->peer_compproto = 0;
553 
554   if (ipcp->cfg.HaveTriggerAddress) {
555     /*
556      * Some implementations of PPP require that we send a
557      * *special* value as our address, even though the rfc specifies
558      * full negotiation (e.g. "0.0.0.0" or Not "0.0.0.0").
559      */
560     ipcp->my_ip = ipcp->cfg.TriggerAddress;
561     log_Printf(LogIPCP, "Using trigger address %s\n",
562               inet_ntoa(ipcp->cfg.TriggerAddress));
563   } else {
564     /*
565      * Otherwise, if we've used an IP number before and it's still within
566      * the network specified on the ``set ifaddr'' line, we really
567      * want to keep that IP number so that we can keep any existing
568      * connections that are bound to that IP.
569      */
570     for (n = 0; n < iface->addrs; n++) {
571       ncprange_getaddr(&iface->addr[n].ifa, &ipaddr);
572       if (ncprange_contains(&ipcp->cfg.my_range, &ipaddr)) {
573         ncpaddr_getip4(&ipaddr, &ipcp->my_ip);
574         break;
575       }
576     }
577     if (n == iface->addrs)
578       ncprange_getip4addr(&ipcp->cfg.my_range, &ipcp->my_ip);
579   }
580 
581   if (IsEnabled(ipcp->cfg.vj.neg)
582 #ifndef NORADIUS
583       || (ipcp->fsm.bundle->radius.valid && ipcp->fsm.bundle->radius.vj)
584 #endif
585      )
586     ipcp->my_compproto = (PROTO_VJCOMP << 16) +
587                          ((ipcp->cfg.vj.slots - 1) << 8) +
588                          ipcp->cfg.vj.slotcomp;
589   else
590     ipcp->my_compproto = 0;
591   sl_compress_init(&ipcp->vj.cslc, ipcp->cfg.vj.slots - 1);
592 
593   ipcp->peer_reject = 0;
594   ipcp->my_reject = 0;
595 
596   /* Copy startup values into ipcp->ns.dns */
597   if (ipcp->cfg.ns.dns[0].s_addr != INADDR_NONE)
598     memcpy(ipcp->ns.dns, ipcp->cfg.ns.dns, sizeof ipcp->ns.dns);
599 }
600 
601 static int
602 numaddresses(struct in_addr mask)
603 {
604   u_int32_t bit, haddr;
605   int n;
606 
607   haddr = ntohl(mask.s_addr);
608   bit = 1;
609   n = 1;
610 
611   do {
612     if (!(haddr & bit))
613       n <<= 1;
614   } while (bit <<= 1);
615 
616   return n;
617 }
618 
619 static int
620 ipcp_proxyarp(struct ipcp *ipcp,
621               int (*proxyfun)(struct bundle *, struct in_addr),
622               const struct iface_addr *addr)
623 {
624   struct bundle *bundle = ipcp->fsm.bundle;
625   struct in_addr peer, mask, ip;
626   int n, ret;
627 
628   if (!ncpaddr_getip4(&addr->peer, &peer)) {
629     log_Printf(LogERROR, "Oops, ipcp_proxyarp() called with unexpected addr\n");
630     return 0;
631   }
632 
633   ret = 0;
634 
635   if (Enabled(bundle, OPT_PROXYALL)) {
636     ncprange_getip4mask(&addr->ifa, &mask);
637     if ((n = numaddresses(mask)) > 256) {
638       log_Printf(LogWARN, "%s: Too many addresses for proxyall\n",
639                  ncprange_ntoa(&addr->ifa));
640       return 0;
641     }
642     ip.s_addr = peer.s_addr & mask.s_addr;
643     if (n >= 4) {
644       ip.s_addr = htonl(ntohl(ip.s_addr) + 1);
645       n -= 2;
646     }
647     while (n) {
648       if (!((ip.s_addr ^ peer.s_addr) & mask.s_addr)) {
649         if (!(ret = (*proxyfun)(bundle, ip)))
650           break;
651         n--;
652       }
653       ip.s_addr = htonl(ntohl(ip.s_addr) + 1);
654     }
655     ret = !n;
656   } else if (Enabled(bundle, OPT_PROXY))
657     ret = (*proxyfun)(bundle, peer);
658 
659   return ret;
660 }
661 
662 static int
663 ipcp_SetIPaddress(struct ipcp *ipcp, struct in_addr myaddr,
664                   struct in_addr hisaddr)
665 {
666   struct bundle *bundle = ipcp->fsm.bundle;
667   struct ncpaddr myncpaddr, hisncpaddr;
668   struct ncprange myrange;
669   struct in_addr mask;
670   struct sockaddr_storage ssdst, ssgw, ssmask;
671   struct sockaddr *sadst, *sagw, *samask;
672 
673   sadst = (struct sockaddr *)&ssdst;
674   sagw = (struct sockaddr *)&ssgw;
675   samask = (struct sockaddr *)&ssmask;
676 
677   ncpaddr_setip4(&hisncpaddr, hisaddr);
678   ncpaddr_setip4(&myncpaddr, myaddr);
679   ncprange_sethost(&myrange, &myncpaddr);
680 
681   mask = addr2mask(myaddr);
682 
683   if (ipcp->ifmask.s_addr != INADDR_ANY &&
684       (ipcp->ifmask.s_addr & mask.s_addr) == mask.s_addr)
685     ncprange_setip4mask(&myrange, ipcp->ifmask);
686 
687   if (!iface_Add(bundle->iface, &bundle->ncp, &myrange, &hisncpaddr,
688                  IFACE_ADD_FIRST|IFACE_FORCE_ADD|IFACE_SYSTEM))
689     return 0;
690 
691   if (!Enabled(bundle, OPT_IFACEALIAS))
692     iface_Clear(bundle->iface, &bundle->ncp, AF_INET,
693                 IFACE_CLEAR_ALIASES|IFACE_SYSTEM);
694 
695   if (bundle->ncp.cfg.sendpipe > 0 || bundle->ncp.cfg.recvpipe > 0) {
696     ncprange_getsa(&myrange, &ssgw, &ssmask);
697     ncpaddr_getsa(&hisncpaddr, &ssdst);
698     rt_Update(bundle, sadst, sagw, samask, NULL, NULL);
699   }
700 
701   if (Enabled(bundle, OPT_SROUTES))
702     route_Change(bundle, bundle->ncp.route, &myncpaddr, &hisncpaddr);
703 
704 #ifndef NORADIUS
705   if (bundle->radius.valid)
706     route_Change(bundle, bundle->radius.routes, &myncpaddr, &hisncpaddr);
707 #endif
708 
709   return 1;	/* Ok */
710 }
711 
712 static struct in_addr
713 ChooseHisAddr(struct bundle *bundle, struct in_addr gw)
714 {
715   struct in_addr try;
716   u_long f;
717 
718   for (f = 0; f < bundle->ncp.ipcp.cfg.peer_list.nItems; f++) {
719     try = iplist_next(&bundle->ncp.ipcp.cfg.peer_list);
720     log_Printf(LogDEBUG, "ChooseHisAddr: Check item %ld (%s)\n",
721               f, inet_ntoa(try));
722     if (ipcp_SetIPaddress(&bundle->ncp.ipcp, gw, try)) {
723       log_Printf(LogIPCP, "Selected IP address %s\n", inet_ntoa(try));
724       break;
725     }
726   }
727 
728   if (f == bundle->ncp.ipcp.cfg.peer_list.nItems) {
729     log_Printf(LogDEBUG, "ChooseHisAddr: All addresses in use !\n");
730     try.s_addr = INADDR_ANY;
731   }
732 
733   return try;
734 }
735 
736 static void
737 IpcpInitRestartCounter(struct fsm *fp, int what)
738 {
739   /* Set fsm timer load */
740   struct ipcp *ipcp = fsm2ipcp(fp);
741 
742   fp->FsmTimer.load = ipcp->cfg.fsm.timeout * SECTICKS;
743   switch (what) {
744     case FSM_REQ_TIMER:
745       fp->restart = ipcp->cfg.fsm.maxreq;
746       break;
747     case FSM_TRM_TIMER:
748       fp->restart = ipcp->cfg.fsm.maxtrm;
749       break;
750     default:
751       fp->restart = 1;
752       break;
753   }
754 }
755 
756 static void
757 IpcpSendConfigReq(struct fsm *fp)
758 {
759   /* Send config REQ please */
760   struct physical *p = link2physical(fp->link);
761   struct ipcp *ipcp = fsm2ipcp(fp);
762   u_char buff[MAX_FSM_OPT_LEN];
763   struct fsm_opt *o;
764 
765   o = (struct fsm_opt *)buff;
766 
767   if ((p && !physical_IsSync(p)) || !REJECTED(ipcp, TY_IPADDR)) {
768     memcpy(o->data, &ipcp->my_ip.s_addr, 4);
769     INC_FSM_OPT(TY_IPADDR, 6, o);
770   }
771 
772   if (ipcp->my_compproto && !REJECTED(ipcp, TY_COMPPROTO)) {
773     if (ipcp->heis1172) {
774       u_int16_t proto = PROTO_VJCOMP;
775 
776       ua_htons(&proto, o->data);
777       INC_FSM_OPT(TY_COMPPROTO, 4, o);
778     } else {
779       struct compreq req;
780 
781       req.proto = htons(ipcp->my_compproto >> 16);
782       req.slots = (ipcp->my_compproto >> 8) & 255;
783       req.compcid = ipcp->my_compproto & 1;
784       memcpy(o->data, &req, 4);
785       INC_FSM_OPT(TY_COMPPROTO, 6, o);
786     }
787   }
788 
789   if (IsEnabled(ipcp->cfg.ns.dns_neg)) {
790     if (!REJECTED(ipcp, TY_PRIMARY_DNS - TY_ADJUST_NS)) {
791       memcpy(o->data, &ipcp->ns.dns[0].s_addr, 4);
792       INC_FSM_OPT(TY_PRIMARY_DNS, 6, o);
793     }
794 
795     if (!REJECTED(ipcp, TY_SECONDARY_DNS - TY_ADJUST_NS)) {
796       memcpy(o->data, &ipcp->ns.dns[1].s_addr, 4);
797       INC_FSM_OPT(TY_SECONDARY_DNS, 6, o);
798     }
799   }
800 
801   fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, (u_char *)o - buff,
802              MB_IPCPOUT);
803 }
804 
805 static void
806 IpcpSentTerminateReq(struct fsm *fp __unused)
807 {
808   /* Term REQ just sent by FSM */
809 }
810 
811 static void
812 IpcpSendTerminateAck(struct fsm *fp, u_char id)
813 {
814   /* Send Term ACK please */
815   fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_IPCPOUT);
816 }
817 
818 static void
819 IpcpLayerStart(struct fsm *fp)
820 {
821   /* We're about to start up ! */
822   struct ipcp *ipcp = fsm2ipcp(fp);
823 
824   log_Printf(LogIPCP, "%s: LayerStart.\n", fp->link->name);
825   throughput_start(&ipcp->throughput, "IPCP throughput",
826                    Enabled(fp->bundle, OPT_THROUGHPUT));
827   fp->more.reqs = fp->more.naks = fp->more.rejs = ipcp->cfg.fsm.maxreq * 3;
828   ipcp->peer_req = 0;
829 }
830 
831 static void
832 IpcpLayerFinish(struct fsm *fp)
833 {
834   /* We're now down */
835   struct ipcp *ipcp = fsm2ipcp(fp);
836 
837   log_Printf(LogIPCP, "%s: LayerFinish.\n", fp->link->name);
838   throughput_stop(&ipcp->throughput);
839   throughput_log(&ipcp->throughput, LogIPCP, NULL);
840 }
841 
842 /*
843  * Called from iface_Add() via ncp_IfaceAddrAdded()
844  */
845 void
846 ipcp_IfaceAddrAdded(struct ipcp *ipcp, const struct iface_addr *addr)
847 {
848   struct bundle *bundle = ipcp->fsm.bundle;
849 
850   if (Enabled(bundle, OPT_PROXY) || Enabled(bundle, OPT_PROXYALL))
851     ipcp_proxyarp(ipcp, arp_SetProxy, addr);
852 }
853 
854 /*
855  * Called from iface_Clear() and iface_Delete() via ncp_IfaceAddrDeleted()
856  */
857 void
858 ipcp_IfaceAddrDeleted(struct ipcp *ipcp, const struct iface_addr *addr)
859 {
860   struct bundle *bundle = ipcp->fsm.bundle;
861 
862   if (Enabled(bundle, OPT_PROXY) || Enabled(bundle, OPT_PROXYALL))
863     ipcp_proxyarp(ipcp, arp_ClearProxy, addr);
864 }
865 
866 static void
867 IpcpLayerDown(struct fsm *fp)
868 {
869   /* About to come down */
870   struct ipcp *ipcp = fsm2ipcp(fp);
871   static int recursing;
872   char addr[16];
873 
874   if (!recursing++) {
875     snprintf(addr, sizeof addr, "%s", inet_ntoa(ipcp->my_ip));
876     log_Printf(LogIPCP, "%s: LayerDown: %s\n", fp->link->name, addr);
877 
878 #ifndef NORADIUS
879     radius_Flush(&fp->bundle->radius);
880     radius_Account(&fp->bundle->radius, &fp->bundle->radacct,
881                    fp->bundle->links, RAD_STOP, &ipcp->throughput);
882 
883     if (*fp->bundle->radius.cfg.file && fp->bundle->radius.filterid)
884       system_Select(fp->bundle, fp->bundle->radius.filterid, LINKDOWNFILE,
885                     NULL, NULL);
886     radius_StopTimer(&fp->bundle->radius);
887 #endif
888 
889     /*
890      * XXX this stuff should really live in the FSM.  Our config should
891      * associate executable sections in files with events.
892      */
893     if (system_Select(fp->bundle, addr, LINKDOWNFILE, NULL, NULL) < 0) {
894       if (bundle_GetLabel(fp->bundle)) {
895          if (system_Select(fp->bundle, bundle_GetLabel(fp->bundle),
896                           LINKDOWNFILE, NULL, NULL) < 0)
897          system_Select(fp->bundle, "MYADDR", LINKDOWNFILE, NULL, NULL);
898       } else
899         system_Select(fp->bundle, "MYADDR", LINKDOWNFILE, NULL, NULL);
900     }
901 
902     ipcp_Setup(ipcp, INADDR_NONE);
903   }
904   recursing--;
905 }
906 
907 int
908 ipcp_InterfaceUp(struct ipcp *ipcp)
909 {
910   if (!ipcp_SetIPaddress(ipcp, ipcp->my_ip, ipcp->peer_ip)) {
911     log_Printf(LogERROR, "ipcp_InterfaceUp: unable to set ip address\n");
912     return 0;
913   }
914 
915   if (!iface_SetFlags(ipcp->fsm.bundle->iface->name, IFF_UP)) {
916     log_Printf(LogERROR, "ipcp_InterfaceUp: Can't set the IFF_UP flag on %s\n",
917                ipcp->fsm.bundle->iface->name);
918     return 0;
919   }
920 
921 #ifndef NONAT
922   if (ipcp->fsm.bundle->NatEnabled)
923     LibAliasSetAddress(la, ipcp->my_ip);
924 #endif
925 
926   return 1;
927 }
928 
929 static int
930 IpcpLayerUp(struct fsm *fp)
931 {
932   /* We're now up */
933   struct ipcp *ipcp = fsm2ipcp(fp);
934   char tbuff[16];
935 
936   log_Printf(LogIPCP, "%s: LayerUp.\n", fp->link->name);
937   snprintf(tbuff, sizeof tbuff, "%s", inet_ntoa(ipcp->my_ip));
938   log_Printf(LogIPCP, "myaddr %s hisaddr = %s\n",
939              tbuff, inet_ntoa(ipcp->peer_ip));
940 
941   if (ipcp->peer_compproto >> 16 == PROTO_VJCOMP)
942     sl_compress_init(&ipcp->vj.cslc, (ipcp->peer_compproto >> 8) & 255);
943 
944   if (!ipcp_InterfaceUp(ipcp))
945     return 0;
946 
947 #ifndef NORADIUS
948   radius_Account_Set_Ip(&fp->bundle->radacct, &ipcp->peer_ip, &ipcp->ifmask);
949   radius_Account(&fp->bundle->radius, &fp->bundle->radacct, fp->bundle->links,
950                  RAD_START, &ipcp->throughput);
951 
952   if (*fp->bundle->radius.cfg.file && fp->bundle->radius.filterid)
953     system_Select(fp->bundle, fp->bundle->radius.filterid, LINKUPFILE,
954                   NULL, NULL);
955   radius_StartTimer(fp->bundle);
956 #endif
957 
958   /*
959    * XXX this stuff should really live in the FSM.  Our config should
960    * associate executable sections in files with events.
961    */
962   if (system_Select(fp->bundle, tbuff, LINKUPFILE, NULL, NULL) < 0) {
963     if (bundle_GetLabel(fp->bundle)) {
964       if (system_Select(fp->bundle, bundle_GetLabel(fp->bundle),
965                        LINKUPFILE, NULL, NULL) < 0)
966         system_Select(fp->bundle, "MYADDR", LINKUPFILE, NULL, NULL);
967     } else
968       system_Select(fp->bundle, "MYADDR", LINKUPFILE, NULL, NULL);
969   }
970 
971   fp->more.reqs = fp->more.naks = fp->more.rejs = ipcp->cfg.fsm.maxreq * 3;
972   log_DisplayPrompts();
973 
974   return 1;
975 }
976 
977 static void
978 ipcp_ValidateReq(struct ipcp *ipcp, struct in_addr ip, struct fsm_decode *dec)
979 {
980   struct bundle *bundle = ipcp->fsm.bundle;
981   struct iface *iface = bundle->iface;
982   struct in_addr myaddr, peer;
983   unsigned n;
984 
985   if (iplist_isvalid(&ipcp->cfg.peer_list)) {
986     ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
987     if (ip.s_addr == INADDR_ANY ||
988         iplist_ip2pos(&ipcp->cfg.peer_list, ip) < 0 ||
989         !ipcp_SetIPaddress(ipcp, myaddr, ip)) {
990       log_Printf(LogIPCP, "%s: Address invalid or already in use\n",
991                  inet_ntoa(ip));
992       /*
993        * If we've already had a valid address configured for the peer,
994        * try NAKing with that so that we don't have to upset things
995        * too much.
996        */
997       for (n = 0; n < iface->addrs; n++) {
998         if (!ncpaddr_getip4(&iface->addr[n].peer, &peer))
999           continue;
1000         if (iplist_ip2pos(&ipcp->cfg.peer_list, peer) >= 0) {
1001           ipcp->peer_ip = peer;
1002           break;
1003         }
1004       }
1005 
1006       if (n == iface->addrs) {
1007         /* Just pick an IP number from our list */
1008         ipcp->peer_ip = ChooseHisAddr(bundle, myaddr);
1009       }
1010 
1011       if (ipcp->peer_ip.s_addr == INADDR_ANY) {
1012         *dec->rejend++ = TY_IPADDR;
1013         *dec->rejend++ = 6;
1014         memcpy(dec->rejend, &ip.s_addr, 4);
1015         dec->rejend += 4;
1016       } else {
1017         *dec->nakend++ = TY_IPADDR;
1018         *dec->nakend++ = 6;
1019         memcpy(dec->nakend, &ipcp->peer_ip.s_addr, 4);
1020         dec->nakend += 4;
1021       }
1022       return;
1023     }
1024   } else if (ip.s_addr == INADDR_ANY ||
1025              !ncprange_containsip4(&ipcp->cfg.peer_range, ip)) {
1026     /*
1027      * If the destination address is not acceptable, NAK with what we
1028      * want to use.
1029      */
1030     *dec->nakend++ = TY_IPADDR;
1031     *dec->nakend++ = 6;
1032     for (n = 0; n < iface->addrs; n++)
1033       if (ncprange_contains(&ipcp->cfg.peer_range, &iface->addr[n].peer)) {
1034         /* We prefer the already-configured address */
1035         ncpaddr_getip4addr(&iface->addr[n].peer, (u_int32_t *)dec->nakend);
1036         break;
1037       }
1038 
1039     if (n == iface->addrs)
1040       memcpy(dec->nakend, &ipcp->peer_ip.s_addr, 4);
1041 
1042     dec->nakend += 4;
1043     return;
1044   }
1045 
1046   ipcp->peer_ip = ip;
1047   *dec->ackend++ = TY_IPADDR;
1048   *dec->ackend++ = 6;
1049   memcpy(dec->ackend, &ip.s_addr, 4);
1050   dec->ackend += 4;
1051 }
1052 
1053 static void
1054 IpcpDecodeConfig(struct fsm *fp, u_char *cp, u_char *end, int mode_type,
1055                  struct fsm_decode *dec)
1056 {
1057   /* Deal with incoming PROTO_IPCP */
1058   struct ncpaddr ncpaddr;
1059   struct ipcp *ipcp = fsm2ipcp(fp);
1060   int gotdnsnak;
1061   u_int32_t compproto;
1062   struct compreq pcomp;
1063   struct in_addr ipaddr, dstipaddr, have_ip;
1064   char tbuff[100], tbuff2[100];
1065   struct fsm_opt *opt, nak;
1066 
1067   gotdnsnak = 0;
1068 
1069   while (end - cp >= (int)sizeof(opt->hdr)) {
1070     if ((opt = fsm_readopt(&cp)) == NULL)
1071       break;
1072 
1073     snprintf(tbuff, sizeof tbuff, " %s[%d]", protoname(opt->hdr.id),
1074              opt->hdr.len);
1075 
1076     switch (opt->hdr.id) {
1077     case TY_IPADDR:		/* RFC1332 */
1078       memcpy(&ipaddr.s_addr, opt->data, 4);
1079       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1080 
1081       switch (mode_type) {
1082       case MODE_REQ:
1083         ipcp->peer_req = 1;
1084         ipcp_ValidateReq(ipcp, ipaddr, dec);
1085         break;
1086 
1087       case MODE_NAK:
1088         if (ncprange_containsip4(&ipcp->cfg.my_range, ipaddr)) {
1089           /* Use address suggested by peer */
1090           snprintf(tbuff2, sizeof tbuff2, "%s changing address: %s ", tbuff,
1091                    inet_ntoa(ipcp->my_ip));
1092           log_Printf(LogIPCP, "%s --> %s\n", tbuff2, inet_ntoa(ipaddr));
1093           ipcp->my_ip = ipaddr;
1094           ncpaddr_setip4(&ncpaddr, ipcp->my_ip);
1095           bundle_AdjustFilters(fp->bundle, &ncpaddr, NULL);
1096         } else {
1097           log_Printf(log_IsKept(LogIPCP) ? LogIPCP : LogPHASE,
1098                     "%s: Unacceptable address!\n", inet_ntoa(ipaddr));
1099           fsm_Close(&ipcp->fsm);
1100         }
1101         break;
1102 
1103       case MODE_REJ:
1104         ipcp->peer_reject |= (1 << opt->hdr.id);
1105         break;
1106       }
1107       break;
1108 
1109     case TY_COMPPROTO:
1110       memcpy(&pcomp, opt->data, sizeof pcomp);
1111       compproto = (ntohs(pcomp.proto) << 16) + ((int)pcomp.slots << 8) +
1112                   pcomp.compcid;
1113       log_Printf(LogIPCP, "%s %s\n", tbuff, vj2asc(compproto));
1114 
1115       switch (mode_type) {
1116       case MODE_REQ:
1117         if (!IsAccepted(ipcp->cfg.vj.neg))
1118           fsm_rej(dec, opt);
1119         else {
1120           switch (opt->hdr.len) {
1121           case 4:		/* RFC1172 */
1122             if (ntohs(pcomp.proto) == PROTO_VJCOMP) {
1123               log_Printf(LogWARN, "Peer is speaking RFC1172 compression "
1124                          "protocol !\n");
1125               ipcp->heis1172 = 1;
1126               ipcp->peer_compproto = compproto;
1127               fsm_ack(dec, opt);
1128             } else {
1129               pcomp.proto = htons(PROTO_VJCOMP);
1130               nak.hdr.id = TY_COMPPROTO;
1131               nak.hdr.len = 4;
1132               memcpy(nak.data, &pcomp, 2);
1133               fsm_nak(dec, &nak);
1134             }
1135             break;
1136           case 6:		/* RFC1332 */
1137             if (ntohs(pcomp.proto) == PROTO_VJCOMP) {
1138 	      /* We know pcomp.slots' max value == MAX_VJ_STATES */
1139               if (pcomp.slots >= MIN_VJ_STATES) {
1140                 /* Ok, we can do that */
1141                 ipcp->peer_compproto = compproto;
1142                 ipcp->heis1172 = 0;
1143                 fsm_ack(dec, opt);
1144               } else {
1145                 /* Get as close as we can to what he wants */
1146                 ipcp->heis1172 = 0;
1147                 pcomp.slots = MIN_VJ_STATES;
1148                 nak.hdr.id = TY_COMPPROTO;
1149                 nak.hdr.len = 4;
1150                 memcpy(nak.data, &pcomp, 2);
1151                 fsm_nak(dec, &nak);
1152               }
1153             } else {
1154               /* What we really want */
1155               pcomp.proto = htons(PROTO_VJCOMP);
1156               pcomp.slots = DEF_VJ_STATES;
1157               pcomp.compcid = 1;
1158               nak.hdr.id = TY_COMPPROTO;
1159               nak.hdr.len = 6;
1160               memcpy(nak.data, &pcomp, sizeof pcomp);
1161               fsm_nak(dec, &nak);
1162             }
1163             break;
1164           default:
1165             fsm_rej(dec, opt);
1166             break;
1167           }
1168         }
1169         break;
1170 
1171       case MODE_NAK:
1172         if (ntohs(pcomp.proto) == PROTO_VJCOMP) {
1173 	  /* We know pcomp.slots' max value == MAX_VJ_STATES */
1174           if (pcomp.slots < MIN_VJ_STATES)
1175             pcomp.slots = MIN_VJ_STATES;
1176           compproto = (ntohs(pcomp.proto) << 16) + (pcomp.slots << 8) +
1177                       pcomp.compcid;
1178         } else
1179           compproto = 0;
1180         log_Printf(LogIPCP, "%s changing compproto: %08x --> %08x\n",
1181                    tbuff, ipcp->my_compproto, compproto);
1182         ipcp->my_compproto = compproto;
1183         break;
1184 
1185       case MODE_REJ:
1186         ipcp->peer_reject |= (1 << opt->hdr.id);
1187         break;
1188       }
1189       break;
1190 
1191     case TY_IPADDRS:		/* RFC1172 */
1192       memcpy(&ipaddr.s_addr, opt->data, 4);
1193       memcpy(&dstipaddr.s_addr, opt->data + 4, 4);
1194       snprintf(tbuff2, sizeof tbuff2, "%s %s,", tbuff, inet_ntoa(ipaddr));
1195       log_Printf(LogIPCP, "%s %s\n", tbuff2, inet_ntoa(dstipaddr));
1196 
1197       switch (mode_type) {
1198       case MODE_REQ:
1199         fsm_rej(dec, opt);
1200         break;
1201 
1202       case MODE_NAK:
1203       case MODE_REJ:
1204         break;
1205       }
1206       break;
1207 
1208     case TY_PRIMARY_DNS:	/* DNS negotiation (rfc1877) */
1209     case TY_SECONDARY_DNS:
1210       memcpy(&ipaddr.s_addr, opt->data, 4);
1211       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1212 
1213       switch (mode_type) {
1214       case MODE_REQ:
1215         if (!IsAccepted(ipcp->cfg.ns.dns_neg)) {
1216           ipcp->my_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1217           fsm_rej(dec, opt);
1218           break;
1219         }
1220         have_ip = ipcp->ns.dns[opt->hdr.id == TY_PRIMARY_DNS ? 0 : 1];
1221 
1222         if (opt->hdr.id == TY_PRIMARY_DNS && ipaddr.s_addr != have_ip.s_addr &&
1223             ipaddr.s_addr == ipcp->ns.dns[1].s_addr) {
1224           /* Swap 'em 'round */
1225           ipcp->ns.dns[0] = ipcp->ns.dns[1];
1226           ipcp->ns.dns[1] = have_ip;
1227           have_ip = ipcp->ns.dns[0];
1228         }
1229 
1230         if (ipaddr.s_addr != have_ip.s_addr) {
1231           /*
1232            * The client has got the DNS stuff wrong (first request) so
1233            * we'll tell 'em how it is
1234            */
1235           nak.hdr.id = opt->hdr.id;
1236           nak.hdr.len = 6;
1237           memcpy(nak.data, &have_ip.s_addr, 4);
1238           fsm_nak(dec, &nak);
1239         } else {
1240           /*
1241            * Otherwise they have it right (this time) so we send an ack packet
1242            * back confirming it... end of story
1243            */
1244           fsm_ack(dec, opt);
1245         }
1246         break;
1247 
1248       case MODE_NAK:
1249         if (IsEnabled(ipcp->cfg.ns.dns_neg)) {
1250           gotdnsnak = 1;
1251           memcpy(&ipcp->ns.dns[opt->hdr.id == TY_PRIMARY_DNS ? 0 : 1].s_addr,
1252                  opt->data, 4);
1253         }
1254         break;
1255 
1256       case MODE_REJ:		/* Can't do much, stop asking */
1257         ipcp->peer_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1258         break;
1259       }
1260       break;
1261 
1262     case TY_PRIMARY_NBNS:	/* M$ NetBIOS nameserver hack (rfc1877) */
1263     case TY_SECONDARY_NBNS:
1264       memcpy(&ipaddr.s_addr, opt->data, 4);
1265       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1266 
1267       switch (mode_type) {
1268       case MODE_REQ:
1269         have_ip.s_addr =
1270           ipcp->cfg.ns.nbns[opt->hdr.id == TY_PRIMARY_NBNS ? 0 : 1].s_addr;
1271 
1272         if (have_ip.s_addr == INADDR_ANY) {
1273           log_Printf(LogIPCP, "NBNS REQ - rejected - nbns not set\n");
1274           ipcp->my_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1275           fsm_rej(dec, opt);
1276           break;
1277         }
1278 
1279         if (ipaddr.s_addr != have_ip.s_addr) {
1280           nak.hdr.id = opt->hdr.id;
1281           nak.hdr.len = 6;
1282           memcpy(nak.data, &have_ip.s_addr, 4);
1283           fsm_nak(dec, &nak);
1284         } else
1285           fsm_ack(dec, opt);
1286         break;
1287 
1288       case MODE_NAK:
1289         log_Printf(LogIPCP, "MS NBNS req %d - NAK??\n", opt->hdr.id);
1290         break;
1291 
1292       case MODE_REJ:
1293         log_Printf(LogIPCP, "MS NBNS req %d - REJ??\n", opt->hdr.id);
1294         break;
1295       }
1296       break;
1297 
1298     default:
1299       if (mode_type != MODE_NOP) {
1300         ipcp->my_reject |= (1 << opt->hdr.id);
1301         fsm_rej(dec, opt);
1302       }
1303       break;
1304     }
1305   }
1306 
1307   if (gotdnsnak) {
1308     if (ipcp->ns.writable) {
1309       log_Printf(LogDEBUG, "Updating resolver\n");
1310       if (!ipcp_WriteDNS(ipcp)) {
1311         ipcp->peer_reject |= (1 << (TY_PRIMARY_DNS - TY_ADJUST_NS));
1312         ipcp->peer_reject |= (1 << (TY_SECONDARY_DNS - TY_ADJUST_NS));
1313       } else
1314         bundle_AdjustDNS(fp->bundle);
1315     } else {
1316       log_Printf(LogDEBUG, "Not updating resolver (readonly)\n");
1317       bundle_AdjustDNS(fp->bundle);
1318     }
1319   }
1320 
1321   if (mode_type != MODE_NOP) {
1322     if (mode_type == MODE_REQ && !ipcp->peer_req) {
1323       if (dec->rejend == dec->rej && dec->nakend == dec->nak) {
1324         /*
1325          * Pretend the peer has requested an IP.
1326          * We do this to ensure that we only send one NAK if the only
1327          * reason for the NAK is because the peer isn't sending a
1328          * TY_IPADDR REQ.  This stops us from repeatedly trying to tell
1329          * the peer that we have to have an IP address on their end.
1330          */
1331         ipcp->peer_req = 1;
1332       }
1333       ipaddr.s_addr = INADDR_ANY;
1334       ipcp_ValidateReq(ipcp, ipaddr, dec);
1335     }
1336     fsm_opt_normalise(dec);
1337   }
1338 }
1339 
1340 extern struct mbuf *
1341 ipcp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
1342 {
1343   /* Got PROTO_IPCP from link */
1344   m_settype(bp, MB_IPCPIN);
1345   if (bundle_Phase(bundle) == PHASE_NETWORK)
1346     fsm_Input(&bundle->ncp.ipcp.fsm, bp);
1347   else {
1348     if (bundle_Phase(bundle) < PHASE_NETWORK)
1349       log_Printf(LogIPCP, "%s: Error: Unexpected IPCP in phase %s (ignored)\n",
1350                  l->name, bundle_PhaseName(bundle));
1351     m_freem(bp);
1352   }
1353   return NULL;
1354 }
1355 
1356 int
1357 ipcp_UseHisIPaddr(struct bundle *bundle, struct in_addr hisaddr)
1358 {
1359   struct ipcp *ipcp = &bundle->ncp.ipcp;
1360   struct in_addr myaddr;
1361 
1362   memset(&ipcp->cfg.peer_range, '\0', sizeof ipcp->cfg.peer_range);
1363   iplist_reset(&ipcp->cfg.peer_list);
1364   ipcp->peer_ip = hisaddr;
1365   ncprange_setip4host(&ipcp->cfg.peer_range, hisaddr);
1366   ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
1367 
1368   return ipcp_SetIPaddress(ipcp, myaddr, hisaddr);
1369 }
1370 
1371 int
1372 ipcp_UseHisaddr(struct bundle *bundle, const char *hisaddr, int setaddr)
1373 {
1374   struct in_addr myaddr;
1375   struct ncp *ncp = &bundle->ncp;
1376   struct ipcp *ipcp = &ncp->ipcp;
1377   struct ncpaddr ncpaddr;
1378 
1379   /* Use `hisaddr' for the peers address (set iface if `setaddr') */
1380   memset(&ipcp->cfg.peer_range, '\0', sizeof ipcp->cfg.peer_range);
1381   iplist_reset(&ipcp->cfg.peer_list);
1382   if (strpbrk(hisaddr, ",-")) {
1383     iplist_setsrc(&ipcp->cfg.peer_list, hisaddr);
1384     if (iplist_isvalid(&ipcp->cfg.peer_list)) {
1385       iplist_setrandpos(&ipcp->cfg.peer_list);
1386       ipcp->peer_ip = ChooseHisAddr(bundle, ipcp->my_ip);
1387       if (ipcp->peer_ip.s_addr == INADDR_ANY) {
1388         log_Printf(LogWARN, "%s: None available !\n", ipcp->cfg.peer_list.src);
1389         return 0;
1390       }
1391       ncprange_setip4host(&ipcp->cfg.peer_range, ipcp->peer_ip);
1392     } else {
1393       log_Printf(LogWARN, "%s: Invalid range !\n", hisaddr);
1394       return 0;
1395     }
1396   } else if (ncprange_aton(&ipcp->cfg.peer_range, ncp, hisaddr) != 0) {
1397     if (ncprange_family(&ipcp->cfg.my_range) != AF_INET) {
1398       log_Printf(LogWARN, "%s: Not an AF_INET address !\n", hisaddr);
1399       return 0;
1400     }
1401     ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
1402     ncprange_getip4addr(&ipcp->cfg.peer_range, &ipcp->peer_ip);
1403 
1404     if (setaddr && !ipcp_SetIPaddress(ipcp, myaddr, ipcp->peer_ip))
1405       return 0;
1406   } else
1407     return 0;
1408 
1409   ncpaddr_setip4(&ncpaddr, ipcp->peer_ip);
1410   bundle_AdjustFilters(bundle, NULL, &ncpaddr);
1411 
1412   return 1;	/* Ok */
1413 }
1414 
1415 struct in_addr
1416 addr2mask(struct in_addr addr)
1417 {
1418   u_int32_t haddr = ntohl(addr.s_addr);
1419 
1420   haddr = IN_CLASSA(haddr) ? IN_CLASSA_NET :
1421           IN_CLASSB(haddr) ? IN_CLASSB_NET :
1422           IN_CLASSC_NET;
1423   addr.s_addr = htonl(haddr);
1424 
1425   return addr;
1426 }
1427 
1428 size_t
1429 ipcp_QueueLen(struct ipcp *ipcp)
1430 {
1431   struct mqueue *q;
1432   size_t result;
1433 
1434   result = 0;
1435   for (q = ipcp->Queue; q < ipcp->Queue + IPCP_QUEUES(ipcp); q++)
1436     result += q->len;
1437 
1438   return result;
1439 }
1440 
1441 int
1442 ipcp_PushPacket(struct ipcp *ipcp, struct link *l)
1443 {
1444   struct bundle *bundle = ipcp->fsm.bundle;
1445   struct mqueue *queue;
1446   struct mbuf *bp;
1447   int m_len;
1448   u_int32_t secs = 0;
1449   unsigned alivesecs = 0;
1450 
1451   if (ipcp->fsm.state != ST_OPENED)
1452     return 0;
1453 
1454   /*
1455    * If ccp is not open but is required, do nothing.
1456    */
1457   if (l->ccp.fsm.state != ST_OPENED && ccp_Required(&l->ccp)) {
1458     log_Printf(LogPHASE, "%s: Not transmitting... waiting for CCP\n", l->name);
1459     return 0;
1460   }
1461 
1462   queue = ipcp->Queue + IPCP_QUEUES(ipcp) - 1;
1463   do {
1464     if (queue->top) {
1465       bp = m_dequeue(queue);
1466       bp = mbuf_Read(bp, &secs, sizeof secs);
1467       bp = m_pullup(bp);
1468       m_len = m_length(bp);
1469       if (!FilterCheck(MBUF_CTOP(bp), AF_INET, &bundle->filter.alive,
1470                        &alivesecs)) {
1471         if (secs == 0)
1472           secs = alivesecs;
1473         bundle_StartIdleTimer(bundle, secs);
1474       }
1475       link_PushPacket(l, bp, bundle, 0, PROTO_IP);
1476       ipcp_AddOutOctets(ipcp, m_len);
1477       return 1;
1478     }
1479   } while (queue-- != ipcp->Queue);
1480 
1481   return 0;
1482 }
1483