xref: /freebsd/usr.sbin/ppp/ipcp.c (revision a35d88931c87cfe6bd38f01d7bad22140b3b38f3)
1 /*-
2  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
3  *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
4  *                           Internet Initiative Japan, Inc (IIJ)
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
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 static struct fsm_callbacks ipcp_Callbacks = {
122   IpcpLayerUp,
123   IpcpLayerDown,
124   IpcpLayerStart,
125   IpcpLayerFinish,
126   IpcpInitRestartCounter,
127   IpcpSendConfigReq,
128   IpcpSentTerminateReq,
129   IpcpSendTerminateAck,
130   IpcpDecodeConfig,
131   fsm_NullRecvResetReq,
132   fsm_NullRecvResetAck
133 };
134 
135 static const char *
136 protoname(int proto)
137 {
138   static struct {
139     int id;
140     const char *txt;
141   } cftypes[] = {
142     /* Check out the latest ``Assigned numbers'' rfc (rfc1700.txt) */
143     { 1, "IPADDRS" },		/* IP-Addresses */	/* deprecated */
144     { 2, "COMPPROTO" },		/* IP-Compression-Protocol */
145     { 3, "IPADDR" },		/* IP-Address */
146     { 129, "PRIDNS" },		/* 129: Primary DNS Server Address */
147     { 130, "PRINBNS" },		/* 130: Primary NBNS Server Address */
148     { 131, "SECDNS" },		/* 131: Secondary DNS Server Address */
149     { 132, "SECNBNS" }		/* 132: Secondary NBNS Server Address */
150   };
151   unsigned f;
152 
153   for (f = 0; f < sizeof cftypes / sizeof *cftypes; f++)
154     if (cftypes[f].id == proto)
155       return cftypes[f].txt;
156 
157   return NumStr(proto, NULL, 0);
158 }
159 
160 void
161 ipcp_AddInOctets(struct ipcp *ipcp, int n)
162 {
163   throughput_addin(&ipcp->throughput, n);
164 }
165 
166 void
167 ipcp_AddOutOctets(struct ipcp *ipcp, int n)
168 {
169   throughput_addout(&ipcp->throughput, n);
170 }
171 
172 void
173 ipcp_LoadDNS(struct ipcp *ipcp)
174 {
175   int fd;
176 
177   ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr = INADDR_NONE;
178 
179   if (ipcp->ns.resolv != NULL) {
180     free(ipcp->ns.resolv);
181     ipcp->ns.resolv = NULL;
182   }
183   if (ipcp->ns.resolv_nons != NULL) {
184     free(ipcp->ns.resolv_nons);
185     ipcp->ns.resolv_nons = NULL;
186   }
187   ipcp->ns.resolver = 0;
188 
189   if ((fd = open(_PATH_RESCONF, O_RDONLY)) != -1) {
190     struct stat st;
191 
192     if (fstat(fd, &st) == 0) {
193       ssize_t got;
194 
195       if ((ipcp->ns.resolv_nons = (char *)malloc(st.st_size + 1)) == NULL)
196         log_Printf(LogERROR, "Failed to malloc %lu for %s: %s\n",
197                    (unsigned long)st.st_size, _PATH_RESCONF, strerror(errno));
198       else if ((ipcp->ns.resolv = (char *)malloc(st.st_size + 1)) == NULL) {
199         log_Printf(LogERROR, "Failed(2) to malloc %lu for %s: %s\n",
200                    (unsigned long)st.st_size, _PATH_RESCONF, strerror(errno));
201         free(ipcp->ns.resolv_nons);
202         ipcp->ns.resolv_nons = NULL;
203       } else if ((got = read(fd, ipcp->ns.resolv, st.st_size)) != st.st_size) {
204         if (got == -1)
205           log_Printf(LogERROR, "Failed to read %s: %s\n",
206                      _PATH_RESCONF, strerror(errno));
207         else
208           log_Printf(LogERROR, "Failed to read %s, got %lu not %lu\n",
209                      _PATH_RESCONF, (unsigned long)got,
210                      (unsigned long)st.st_size);
211         free(ipcp->ns.resolv_nons);
212         ipcp->ns.resolv_nons = NULL;
213         free(ipcp->ns.resolv);
214         ipcp->ns.resolv = NULL;
215       } else {
216         char *cp, *cp_nons, *ncp, ch;
217         int n;
218 
219         ipcp->ns.resolv[st.st_size] = '\0';
220         ipcp->ns.resolver = 1;
221 
222         cp_nons = ipcp->ns.resolv_nons;
223         cp = ipcp->ns.resolv;
224         n = 0;
225 
226         while ((ncp = strstr(cp, "nameserver")) != NULL) {
227           if (ncp != cp) {
228             memcpy(cp_nons, cp, ncp - cp);
229             cp_nons += ncp - cp;
230           }
231           if ((ncp != cp && ncp[-1] != '\n') || !issep(ncp[10])) {
232             memcpy(cp_nons, ncp, 9);
233             cp_nons += 9;
234             cp = ncp + 9;	/* Can't match "nameserver" at cp... */
235             continue;
236           }
237 
238           for (cp = ncp + 11; issep(*cp); cp++)	/* Skip whitespace */
239             ;
240 
241           for (ncp = cp; isip(*ncp); ncp++)		/* Jump over IP */
242             ;
243 
244           ch = *ncp;
245           *ncp = '\0';
246           if (n < 2 && inet_aton(cp, ipcp->ns.dns))
247             n++;
248           *ncp = ch;
249 
250           if ((cp = strchr(ncp, '\n')) == NULL)	/* Point at next line */
251             cp = ncp + strlen(ncp);
252           else
253             cp++;
254         }
255         strcpy(cp_nons, cp);	/* Copy the end - including the NUL */
256         cp_nons += strlen(cp_nons) - 1;
257         while (cp_nons >= ipcp->ns.resolv_nons && *cp_nons == '\n')
258           *cp_nons-- = '\0';
259         if (n == 2 && ipcp->ns.dns[0].s_addr == INADDR_ANY) {
260           ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr;
261           ipcp->ns.dns[1].s_addr = INADDR_ANY;
262         }
263         bundle_AdjustDNS(ipcp->fsm.bundle);
264       }
265     } else
266       log_Printf(LogERROR, "Failed to stat opened %s: %s\n",
267                  _PATH_RESCONF, strerror(errno));
268 
269     close(fd);
270   }
271 }
272 
273 int
274 ipcp_WriteDNS(struct ipcp *ipcp)
275 {
276   const char *paddr;
277   mode_t mask;
278   FILE *fp;
279 
280   if (ipcp->ns.dns[0].s_addr == INADDR_ANY &&
281       ipcp->ns.dns[1].s_addr == INADDR_ANY) {
282     log_Printf(LogIPCP, "%s not modified: All nameservers NAKd\n",
283               _PATH_RESCONF);
284     return 0;
285   }
286 
287   if (ipcp->ns.dns[0].s_addr == INADDR_ANY) {
288     ipcp->ns.dns[0].s_addr = ipcp->ns.dns[1].s_addr;
289     ipcp->ns.dns[1].s_addr = INADDR_ANY;
290   }
291 
292   mask = umask(022);
293   if ((fp = ID0fopen(_PATH_RESCONF, "w")) != NULL) {
294     umask(mask);
295     if (ipcp->ns.resolv_nons)
296       fputs(ipcp->ns.resolv_nons, fp);
297     paddr = inet_ntoa(ipcp->ns.dns[0]);
298     log_Printf(LogIPCP, "Primary nameserver set to %s\n", paddr);
299     fprintf(fp, "\nnameserver %s\n", paddr);
300     if (ipcp->ns.dns[1].s_addr != INADDR_ANY &&
301         ipcp->ns.dns[1].s_addr != INADDR_NONE &&
302         ipcp->ns.dns[1].s_addr != ipcp->ns.dns[0].s_addr) {
303       paddr = inet_ntoa(ipcp->ns.dns[1]);
304       log_Printf(LogIPCP, "Secondary nameserver set to %s\n", paddr);
305       fprintf(fp, "nameserver %s\n", paddr);
306     }
307     if (fclose(fp) == EOF) {
308       log_Printf(LogERROR, "write(): Failed updating %s: %s\n", _PATH_RESCONF,
309                  strerror(errno));
310       return 0;
311     }
312   } else
313     umask(mask);
314 
315   return 1;
316 }
317 
318 void
319 ipcp_RestoreDNS(struct ipcp *ipcp)
320 {
321   if (ipcp->ns.resolver) {
322     ssize_t got, len;
323     int fd;
324 
325     if ((fd = ID0open(_PATH_RESCONF, O_WRONLY|O_TRUNC, 0644)) != -1) {
326       len = strlen(ipcp->ns.resolv);
327       if ((got = write(fd, ipcp->ns.resolv, len)) != len) {
328         if (got == -1)
329           log_Printf(LogERROR, "Failed rewriting %s: write: %s\n",
330                      _PATH_RESCONF, strerror(errno));
331         else
332           log_Printf(LogERROR, "Failed rewriting %s: wrote %ld of %ld\n",
333                      _PATH_RESCONF, (long)got, (long)len);
334       }
335       close(fd);
336     } else
337       log_Printf(LogERROR, "Failed rewriting %s: open: %s\n", _PATH_RESCONF,
338                  strerror(errno));
339   } else if (remove(_PATH_RESCONF) == -1)
340     log_Printf(LogERROR, "Failed removing %s: %s\n", _PATH_RESCONF,
341                strerror(errno));
342 
343 }
344 
345 int
346 ipcp_Show(struct cmdargs const *arg)
347 {
348   struct ipcp *ipcp = &arg->bundle->ncp.ipcp;
349 
350   prompt_Printf(arg->prompt, "%s [%s]\n", ipcp->fsm.name,
351                 State2Nam(ipcp->fsm.state));
352   if (ipcp->fsm.state == ST_OPENED) {
353     prompt_Printf(arg->prompt, " His side:        %s, %s\n",
354                   inet_ntoa(ipcp->peer_ip), vj2asc(ipcp->peer_compproto));
355     prompt_Printf(arg->prompt, " My side:         %s, %s\n",
356                   inet_ntoa(ipcp->my_ip), vj2asc(ipcp->my_compproto));
357     prompt_Printf(arg->prompt, " Queued packets:  %lu\n",
358                   (unsigned long)ipcp_QueueLen(ipcp));
359   }
360 
361   prompt_Printf(arg->prompt, "\nDefaults:\n");
362   prompt_Printf(arg->prompt, " FSM retry = %us, max %u Config"
363                 " REQ%s, %u Term REQ%s\n", ipcp->cfg.fsm.timeout,
364                 ipcp->cfg.fsm.maxreq, ipcp->cfg.fsm.maxreq == 1 ? "" : "s",
365                 ipcp->cfg.fsm.maxtrm, ipcp->cfg.fsm.maxtrm == 1 ? "" : "s");
366   prompt_Printf(arg->prompt, " My Address:      %s\n",
367                 ncprange_ntoa(&ipcp->cfg.my_range));
368   if (ipcp->cfg.HaveTriggerAddress)
369     prompt_Printf(arg->prompt, " Trigger address: %s\n",
370                   inet_ntoa(ipcp->cfg.TriggerAddress));
371 
372   prompt_Printf(arg->prompt, " VJ compression:  %s (%d slots %s slot "
373                 "compression)\n", command_ShowNegval(ipcp->cfg.vj.neg),
374                 ipcp->cfg.vj.slots, ipcp->cfg.vj.slotcomp ? "with" : "without");
375 
376   if (iplist_isvalid(&ipcp->cfg.peer_list))
377     prompt_Printf(arg->prompt, " His Address:     %s\n",
378                   ipcp->cfg.peer_list.src);
379   else
380     prompt_Printf(arg->prompt, " His Address:     %s\n",
381                   ncprange_ntoa(&ipcp->cfg.peer_range));
382 
383   prompt_Printf(arg->prompt, " DNS:             %s",
384                 ipcp->cfg.ns.dns[0].s_addr == INADDR_NONE ?
385                 "none" : inet_ntoa(ipcp->cfg.ns.dns[0]));
386   if (ipcp->cfg.ns.dns[1].s_addr != INADDR_NONE)
387     prompt_Printf(arg->prompt, ", %s",
388                   inet_ntoa(ipcp->cfg.ns.dns[1]));
389   prompt_Printf(arg->prompt, ", %s\n",
390                 command_ShowNegval(ipcp->cfg.ns.dns_neg));
391   prompt_Printf(arg->prompt, " Resolver DNS:    %s",
392                 ipcp->ns.dns[0].s_addr == INADDR_NONE ?
393                 "none" : inet_ntoa(ipcp->ns.dns[0]));
394   if (ipcp->ns.dns[1].s_addr != INADDR_NONE &&
395       ipcp->ns.dns[1].s_addr != ipcp->ns.dns[0].s_addr)
396     prompt_Printf(arg->prompt, ", %s",
397                   inet_ntoa(ipcp->ns.dns[1]));
398   prompt_Printf(arg->prompt, "\n NetBIOS NS:      %s, ",
399                 inet_ntoa(ipcp->cfg.ns.nbns[0]));
400   prompt_Printf(arg->prompt, "%s\n\n",
401                 inet_ntoa(ipcp->cfg.ns.nbns[1]));
402 
403   throughput_disp(&ipcp->throughput, arg->prompt);
404 
405   return 0;
406 }
407 
408 int
409 ipcp_vjset(struct cmdargs const *arg)
410 {
411   if (arg->argc != arg->argn+2)
412     return -1;
413   if (!strcasecmp(arg->argv[arg->argn], "slots")) {
414     int slots;
415 
416     slots = atoi(arg->argv[arg->argn+1]);
417     if (slots < 4 || slots > 16)
418       return 1;
419     arg->bundle->ncp.ipcp.cfg.vj.slots = slots;
420     return 0;
421   } else if (!strcasecmp(arg->argv[arg->argn], "slotcomp")) {
422     if (!strcasecmp(arg->argv[arg->argn+1], "on"))
423       arg->bundle->ncp.ipcp.cfg.vj.slotcomp = 1;
424     else if (!strcasecmp(arg->argv[arg->argn+1], "off"))
425       arg->bundle->ncp.ipcp.cfg.vj.slotcomp = 0;
426     else
427       return 2;
428     return 0;
429   }
430   return -1;
431 }
432 
433 void
434 ipcp_Init(struct ipcp *ipcp, struct bundle *bundle, struct link *l,
435           const struct fsm_parent *parent)
436 {
437   struct hostent *hp;
438   struct in_addr host;
439   char name[MAXHOSTNAMELEN];
440   static const char * const timer_names[] =
441     {"IPCP restart", "IPCP openmode", "IPCP stopped"};
442 
443   fsm_Init(&ipcp->fsm, "IPCP", PROTO_IPCP, 1, IPCP_MAXCODE, LogIPCP,
444            bundle, l, parent, &ipcp_Callbacks, timer_names);
445 
446   ipcp->cfg.vj.slots = DEF_VJ_STATES;
447   ipcp->cfg.vj.slotcomp = 1;
448   memset(&ipcp->cfg.my_range, '\0', sizeof ipcp->cfg.my_range);
449 
450   host.s_addr = htonl(INADDR_LOOPBACK);
451   ipcp->cfg.netmask.s_addr = INADDR_ANY;
452   if (gethostname(name, sizeof name) == 0) {
453     hp = gethostbyname(name);
454     if (hp && hp->h_addrtype == AF_INET && hp->h_length == sizeof host.s_addr)
455       memcpy(&host.s_addr, hp->h_addr, sizeof host.s_addr);
456   }
457   ncprange_setip4(&ipcp->cfg.my_range, host, ipcp->cfg.netmask);
458   ncprange_setip4(&ipcp->cfg.peer_range, ipcp->cfg.netmask, ipcp->cfg.netmask);
459 
460   iplist_setsrc(&ipcp->cfg.peer_list, "");
461   ipcp->cfg.HaveTriggerAddress = 0;
462 
463   ipcp->cfg.ns.dns[0].s_addr = INADDR_NONE;
464   ipcp->cfg.ns.dns[1].s_addr = INADDR_NONE;
465   ipcp->cfg.ns.dns_neg = 0;
466   ipcp->cfg.ns.nbns[0].s_addr = INADDR_ANY;
467   ipcp->cfg.ns.nbns[1].s_addr = INADDR_ANY;
468 
469   ipcp->cfg.fsm.timeout = DEF_FSMRETRY;
470   ipcp->cfg.fsm.maxreq = DEF_FSMTRIES;
471   ipcp->cfg.fsm.maxtrm = DEF_FSMTRIES;
472   ipcp->cfg.vj.neg = NEG_ENABLED|NEG_ACCEPTED;
473 
474   memset(&ipcp->vj, '\0', sizeof ipcp->vj);
475 
476   ipcp->ns.resolv = NULL;
477   ipcp->ns.resolv_nons = NULL;
478   ipcp->ns.writable = 1;
479   ipcp_LoadDNS(ipcp);
480 
481   throughput_init(&ipcp->throughput, SAMPLE_PERIOD);
482   memset(ipcp->Queue, '\0', sizeof ipcp->Queue);
483   ipcp_Setup(ipcp, INADDR_NONE);
484 }
485 
486 void
487 ipcp_Destroy(struct ipcp *ipcp)
488 {
489   throughput_destroy(&ipcp->throughput);
490 
491   if (ipcp->ns.resolv != NULL) {
492     free(ipcp->ns.resolv);
493     ipcp->ns.resolv = NULL;
494   }
495   if (ipcp->ns.resolv_nons != NULL) {
496     free(ipcp->ns.resolv_nons);
497     ipcp->ns.resolv_nons = NULL;
498   }
499 }
500 
501 void
502 ipcp_SetLink(struct ipcp *ipcp, struct link *l)
503 {
504   ipcp->fsm.link = l;
505 }
506 
507 void
508 ipcp_Setup(struct ipcp *ipcp, u_int32_t mask)
509 {
510   struct iface *iface = ipcp->fsm.bundle->iface;
511   struct ncpaddr ipaddr;
512   struct in_addr peer;
513   int pos;
514   unsigned n;
515 
516   ipcp->fsm.open_mode = 0;
517   ipcp->ifmask.s_addr = mask == INADDR_NONE ? ipcp->cfg.netmask.s_addr : mask;
518 
519   if (iplist_isvalid(&ipcp->cfg.peer_list)) {
520     /* Try to give the peer a previously configured IP address */
521     for (n = 0; n < iface->addrs; n++) {
522       if (!ncpaddr_getip4(&iface->addr[n].peer, &peer))
523         continue;
524       if ((pos = iplist_ip2pos(&ipcp->cfg.peer_list, peer)) != -1) {
525         ncpaddr_setip4(&ipaddr, iplist_setcurpos(&ipcp->cfg.peer_list, pos));
526         break;
527       }
528     }
529     if (n == iface->addrs)
530       /* Ok, so none of 'em fit.... pick a random one */
531       ncpaddr_setip4(&ipaddr, iplist_setrandpos(&ipcp->cfg.peer_list));
532 
533     ncprange_sethost(&ipcp->cfg.peer_range, &ipaddr);
534   }
535 
536   ipcp->heis1172 = 0;
537   ipcp->peer_req = 0;
538   ncprange_getip4addr(&ipcp->cfg.peer_range, &ipcp->peer_ip);
539   ipcp->peer_compproto = 0;
540 
541   if (ipcp->cfg.HaveTriggerAddress) {
542     /*
543      * Some implementations of PPP require that we send a
544      * *special* value as our address, even though the rfc specifies
545      * full negotiation (e.g. "0.0.0.0" or Not "0.0.0.0").
546      */
547     ipcp->my_ip = ipcp->cfg.TriggerAddress;
548     log_Printf(LogIPCP, "Using trigger address %s\n",
549               inet_ntoa(ipcp->cfg.TriggerAddress));
550   } else {
551     /*
552      * Otherwise, if we've used an IP number before and it's still within
553      * the network specified on the ``set ifaddr'' line, we really
554      * want to keep that IP number so that we can keep any existing
555      * connections that are bound to that IP.
556      */
557     for (n = 0; n < iface->addrs; n++) {
558       ncprange_getaddr(&iface->addr[n].ifa, &ipaddr);
559       if (ncprange_contains(&ipcp->cfg.my_range, &ipaddr)) {
560         ncpaddr_getip4(&ipaddr, &ipcp->my_ip);
561         break;
562       }
563     }
564     if (n == iface->addrs)
565       ncprange_getip4addr(&ipcp->cfg.my_range, &ipcp->my_ip);
566   }
567 
568   if (IsEnabled(ipcp->cfg.vj.neg)
569 #ifndef NORADIUS
570       || (ipcp->fsm.bundle->radius.valid && ipcp->fsm.bundle->radius.vj)
571 #endif
572      )
573     ipcp->my_compproto = (PROTO_VJCOMP << 16) +
574                          ((ipcp->cfg.vj.slots - 1) << 8) +
575                          ipcp->cfg.vj.slotcomp;
576   else
577     ipcp->my_compproto = 0;
578   sl_compress_init(&ipcp->vj.cslc, ipcp->cfg.vj.slots - 1);
579 
580   ipcp->peer_reject = 0;
581   ipcp->my_reject = 0;
582 
583   /* Copy startup values into ipcp->ns.dns */
584   if (ipcp->cfg.ns.dns[0].s_addr != INADDR_NONE)
585     memcpy(ipcp->ns.dns, ipcp->cfg.ns.dns, sizeof ipcp->ns.dns);
586 }
587 
588 static int
589 numaddresses(struct in_addr mask)
590 {
591   u_int32_t bit, haddr;
592   int n;
593 
594   haddr = ntohl(mask.s_addr);
595   bit = 1;
596   n = 1;
597 
598   do {
599     if (!(haddr & bit))
600       n <<= 1;
601   } while (bit <<= 1);
602 
603   return n;
604 }
605 
606 static int
607 ipcp_proxyarp(struct ipcp *ipcp,
608               int (*proxyfun)(struct bundle *, struct in_addr),
609               const struct iface_addr *addr)
610 {
611   struct bundle *bundle = ipcp->fsm.bundle;
612   struct in_addr peer, mask, ip;
613   int n, ret;
614 
615   if (!ncpaddr_getip4(&addr->peer, &peer)) {
616     log_Printf(LogERROR, "Oops, ipcp_proxyarp() called with unexpected addr\n");
617     return 0;
618   }
619 
620   ret = 0;
621 
622   if (Enabled(bundle, OPT_PROXYALL)) {
623     ncprange_getip4mask(&addr->ifa, &mask);
624     if ((n = numaddresses(mask)) > 256) {
625       log_Printf(LogWARN, "%s: Too many addresses for proxyall\n",
626                  ncprange_ntoa(&addr->ifa));
627       return 0;
628     }
629     ip.s_addr = peer.s_addr & mask.s_addr;
630     if (n >= 4) {
631       ip.s_addr = htonl(ntohl(ip.s_addr) + 1);
632       n -= 2;
633     }
634     while (n) {
635       if (!((ip.s_addr ^ peer.s_addr) & mask.s_addr)) {
636         if (!(ret = (*proxyfun)(bundle, ip)))
637           break;
638         n--;
639       }
640       ip.s_addr = htonl(ntohl(ip.s_addr) + 1);
641     }
642     ret = !n;
643   } else if (Enabled(bundle, OPT_PROXY))
644     ret = (*proxyfun)(bundle, peer);
645 
646   return ret;
647 }
648 
649 static int
650 ipcp_SetIPaddress(struct ipcp *ipcp, struct in_addr myaddr,
651                   struct in_addr hisaddr)
652 {
653   struct bundle *bundle = ipcp->fsm.bundle;
654   struct ncpaddr myncpaddr, hisncpaddr;
655   struct ncprange myrange;
656   struct in_addr mask;
657   struct sockaddr_storage ssdst, ssgw, ssmask;
658   struct sockaddr *sadst, *sagw, *samask;
659 
660   sadst = (struct sockaddr *)&ssdst;
661   sagw = (struct sockaddr *)&ssgw;
662   samask = (struct sockaddr *)&ssmask;
663 
664   ncpaddr_setip4(&hisncpaddr, hisaddr);
665   ncpaddr_setip4(&myncpaddr, myaddr);
666   ncprange_sethost(&myrange, &myncpaddr);
667 
668   mask = addr2mask(myaddr);
669 
670   if (ipcp->ifmask.s_addr != INADDR_ANY &&
671       (ipcp->ifmask.s_addr & mask.s_addr) == mask.s_addr)
672     ncprange_setip4mask(&myrange, ipcp->ifmask);
673 
674   if (!iface_Add(bundle->iface, &bundle->ncp, &myrange, &hisncpaddr,
675                  IFACE_ADD_FIRST|IFACE_FORCE_ADD|IFACE_SYSTEM))
676     return 0;
677 
678   if (!Enabled(bundle, OPT_IFACEALIAS))
679     iface_Clear(bundle->iface, &bundle->ncp, AF_INET,
680                 IFACE_CLEAR_ALIASES|IFACE_SYSTEM);
681 
682   if (bundle->ncp.cfg.sendpipe > 0 || bundle->ncp.cfg.recvpipe > 0) {
683     ncprange_getsa(&myrange, &ssgw, &ssmask);
684     ncpaddr_getsa(&hisncpaddr, &ssdst);
685     rt_Update(bundle, sadst, sagw, samask);
686   }
687 
688   if (Enabled(bundle, OPT_SROUTES))
689     route_Change(bundle, bundle->ncp.route, &myncpaddr, &hisncpaddr);
690 
691 #ifndef NORADIUS
692   if (bundle->radius.valid)
693     route_Change(bundle, bundle->radius.routes, &myncpaddr, &hisncpaddr);
694 #endif
695 
696   return 1;	/* Ok */
697 }
698 
699 static struct in_addr
700 ChooseHisAddr(struct bundle *bundle, struct in_addr gw)
701 {
702   struct in_addr try;
703   u_long f;
704 
705   for (f = 0; f < bundle->ncp.ipcp.cfg.peer_list.nItems; f++) {
706     try = iplist_next(&bundle->ncp.ipcp.cfg.peer_list);
707     log_Printf(LogDEBUG, "ChooseHisAddr: Check item %ld (%s)\n",
708               f, inet_ntoa(try));
709     if (ipcp_SetIPaddress(&bundle->ncp.ipcp, gw, try)) {
710       log_Printf(LogIPCP, "Selected IP address %s\n", inet_ntoa(try));
711       break;
712     }
713   }
714 
715   if (f == bundle->ncp.ipcp.cfg.peer_list.nItems) {
716     log_Printf(LogDEBUG, "ChooseHisAddr: All addresses in use !\n");
717     try.s_addr = INADDR_ANY;
718   }
719 
720   return try;
721 }
722 
723 static void
724 IpcpInitRestartCounter(struct fsm *fp, int what)
725 {
726   /* Set fsm timer load */
727   struct ipcp *ipcp = fsm2ipcp(fp);
728 
729   fp->FsmTimer.load = ipcp->cfg.fsm.timeout * SECTICKS;
730   switch (what) {
731     case FSM_REQ_TIMER:
732       fp->restart = ipcp->cfg.fsm.maxreq;
733       break;
734     case FSM_TRM_TIMER:
735       fp->restart = ipcp->cfg.fsm.maxtrm;
736       break;
737     default:
738       fp->restart = 1;
739       break;
740   }
741 }
742 
743 static void
744 IpcpSendConfigReq(struct fsm *fp)
745 {
746   /* Send config REQ please */
747   struct physical *p = link2physical(fp->link);
748   struct ipcp *ipcp = fsm2ipcp(fp);
749   u_char buff[24];
750   struct fsm_opt *o;
751 
752   o = (struct fsm_opt *)buff;
753 
754   if ((p && !physical_IsSync(p)) || !REJECTED(ipcp, TY_IPADDR)) {
755     memcpy(o->data, &ipcp->my_ip.s_addr, 4);
756     INC_FSM_OPT(TY_IPADDR, 6, o);
757   }
758 
759   if (ipcp->my_compproto && !REJECTED(ipcp, TY_COMPPROTO)) {
760     if (ipcp->heis1172) {
761       u_int16_t proto = PROTO_VJCOMP;
762 
763       ua_htons(&proto, o->data);
764       INC_FSM_OPT(TY_COMPPROTO, 4, o);
765     } else {
766       struct compreq req;
767 
768       req.proto = htons(ipcp->my_compproto >> 16);
769       req.slots = (ipcp->my_compproto >> 8) & 255;
770       req.compcid = ipcp->my_compproto & 1;
771       memcpy(o->data, &req, 4);
772       INC_FSM_OPT(TY_COMPPROTO, 6, o);
773     }
774   }
775 
776   if (IsEnabled(ipcp->cfg.ns.dns_neg)) {
777     if (!REJECTED(ipcp, TY_PRIMARY_DNS - TY_ADJUST_NS)) {
778       memcpy(o->data, &ipcp->ns.dns[0].s_addr, 4);
779       INC_FSM_OPT(TY_PRIMARY_DNS, 6, o);
780     }
781 
782     if (!REJECTED(ipcp, TY_SECONDARY_DNS - TY_ADJUST_NS)) {
783       memcpy(o->data, &ipcp->ns.dns[1].s_addr, 4);
784       INC_FSM_OPT(TY_SECONDARY_DNS, 6, o);
785     }
786   }
787 
788   fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, (u_char *)o - buff,
789              MB_IPCPOUT);
790 }
791 
792 static void
793 IpcpSentTerminateReq(struct fsm *fp __unused)
794 {
795   /* Term REQ just sent by FSM */
796 }
797 
798 static void
799 IpcpSendTerminateAck(struct fsm *fp, u_char id)
800 {
801   /* Send Term ACK please */
802   fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_IPCPOUT);
803 }
804 
805 static void
806 IpcpLayerStart(struct fsm *fp)
807 {
808   /* We're about to start up ! */
809   struct ipcp *ipcp = fsm2ipcp(fp);
810 
811   log_Printf(LogIPCP, "%s: LayerStart.\n", fp->link->name);
812   throughput_start(&ipcp->throughput, "IPCP throughput",
813                    Enabled(fp->bundle, OPT_THROUGHPUT));
814   fp->more.reqs = fp->more.naks = fp->more.rejs = ipcp->cfg.fsm.maxreq * 3;
815   ipcp->peer_req = 0;
816 }
817 
818 static void
819 IpcpLayerFinish(struct fsm *fp)
820 {
821   /* We're now down */
822   struct ipcp *ipcp = fsm2ipcp(fp);
823 
824   log_Printf(LogIPCP, "%s: LayerFinish.\n", fp->link->name);
825   throughput_stop(&ipcp->throughput);
826   throughput_log(&ipcp->throughput, LogIPCP, NULL);
827 }
828 
829 /*
830  * Called from iface_Add() via ncp_IfaceAddrAdded()
831  */
832 void
833 ipcp_IfaceAddrAdded(struct ipcp *ipcp, const struct iface_addr *addr)
834 {
835   struct bundle *bundle = ipcp->fsm.bundle;
836 
837   if (Enabled(bundle, OPT_PROXY) || Enabled(bundle, OPT_PROXYALL))
838     ipcp_proxyarp(ipcp, arp_SetProxy, addr);
839 }
840 
841 /*
842  * Called from iface_Clear() and iface_Delete() via ncp_IfaceAddrDeleted()
843  */
844 void
845 ipcp_IfaceAddrDeleted(struct ipcp *ipcp, const struct iface_addr *addr)
846 {
847   struct bundle *bundle = ipcp->fsm.bundle;
848 
849   if (Enabled(bundle, OPT_PROXY) || Enabled(bundle, OPT_PROXYALL))
850     ipcp_proxyarp(ipcp, arp_ClearProxy, addr);
851 }
852 
853 static void
854 IpcpLayerDown(struct fsm *fp)
855 {
856   /* About to come down */
857   struct ipcp *ipcp = fsm2ipcp(fp);
858   static int recursing;
859   char addr[16];
860 
861   if (!recursing++) {
862     snprintf(addr, sizeof addr, "%s", inet_ntoa(ipcp->my_ip));
863     log_Printf(LogIPCP, "%s: LayerDown: %s\n", fp->link->name, addr);
864 
865 #ifndef NORADIUS
866     radius_Account(&fp->bundle->radius, &fp->bundle->radacct,
867                    fp->bundle->links, RAD_STOP, &ipcp->throughput);
868 
869     if (fp->bundle->radius.cfg.file && fp->bundle->radius.filterid)
870       system_Select(fp->bundle, fp->bundle->radius.filterid, LINKDOWNFILE,
871                     NULL, NULL);
872     radius_StopTimer(&fp->bundle->radius);
873 #endif
874 
875     /*
876      * XXX this stuff should really live in the FSM.  Our config should
877      * associate executable sections in files with events.
878      */
879     if (system_Select(fp->bundle, addr, LINKDOWNFILE, NULL, NULL) < 0) {
880       if (bundle_GetLabel(fp->bundle)) {
881          if (system_Select(fp->bundle, bundle_GetLabel(fp->bundle),
882                           LINKDOWNFILE, NULL, NULL) < 0)
883          system_Select(fp->bundle, "MYADDR", LINKDOWNFILE, NULL, NULL);
884       } else
885         system_Select(fp->bundle, "MYADDR", LINKDOWNFILE, NULL, NULL);
886     }
887 
888     ipcp_Setup(ipcp, INADDR_NONE);
889   }
890   recursing--;
891 }
892 
893 int
894 ipcp_InterfaceUp(struct ipcp *ipcp)
895 {
896   if (!ipcp_SetIPaddress(ipcp, ipcp->my_ip, ipcp->peer_ip)) {
897     log_Printf(LogERROR, "ipcp_InterfaceUp: unable to set ip address\n");
898     return 0;
899   }
900 
901   if (!iface_SetFlags(ipcp->fsm.bundle->iface->name, IFF_UP)) {
902     log_Printf(LogERROR, "ipcp_InterfaceUp: Can't set the IFF_UP flag on %s\n",
903                ipcp->fsm.bundle->iface->name);
904     return 0;
905   }
906 
907 #ifndef NONAT
908   if (ipcp->fsm.bundle->NatEnabled)
909     PacketAliasSetAddress(ipcp->my_ip);
910 #endif
911 
912   return 1;
913 }
914 
915 static int
916 IpcpLayerUp(struct fsm *fp)
917 {
918   /* We're now up */
919   struct ipcp *ipcp = fsm2ipcp(fp);
920   char tbuff[16];
921 
922   log_Printf(LogIPCP, "%s: LayerUp.\n", fp->link->name);
923   snprintf(tbuff, sizeof tbuff, "%s", inet_ntoa(ipcp->my_ip));
924   log_Printf(LogIPCP, "myaddr %s hisaddr = %s\n",
925              tbuff, inet_ntoa(ipcp->peer_ip));
926 
927   if (ipcp->peer_compproto >> 16 == PROTO_VJCOMP)
928     sl_compress_init(&ipcp->vj.cslc, (ipcp->peer_compproto >> 8) & 255);
929 
930   if (!ipcp_InterfaceUp(ipcp))
931     return 0;
932 
933 #ifndef NORADIUS
934   radius_Account_Set_Ip(&fp->bundle->radacct, &ipcp->peer_ip, &ipcp->ifmask);
935   radius_Account(&fp->bundle->radius, &fp->bundle->radacct, fp->bundle->links,
936                  RAD_START, &ipcp->throughput);
937 
938   if (fp->bundle->radius.cfg.file && fp->bundle->radius.filterid)
939     system_Select(fp->bundle, fp->bundle->radius.filterid, LINKUPFILE,
940                   NULL, NULL);
941   radius_StartTimer(fp->bundle);
942 #endif
943 
944   /*
945    * XXX this stuff should really live in the FSM.  Our config should
946    * associate executable sections in files with events.
947    */
948   if (system_Select(fp->bundle, tbuff, LINKUPFILE, NULL, NULL) < 0) {
949     if (bundle_GetLabel(fp->bundle)) {
950       if (system_Select(fp->bundle, bundle_GetLabel(fp->bundle),
951                        LINKUPFILE, NULL, NULL) < 0)
952         system_Select(fp->bundle, "MYADDR", LINKUPFILE, NULL, NULL);
953     } else
954       system_Select(fp->bundle, "MYADDR", LINKUPFILE, NULL, NULL);
955   }
956 
957   fp->more.reqs = fp->more.naks = fp->more.rejs = ipcp->cfg.fsm.maxreq * 3;
958   log_DisplayPrompts();
959 
960   return 1;
961 }
962 
963 static void
964 ipcp_ValidateReq(struct ipcp *ipcp, struct in_addr ip, struct fsm_decode *dec)
965 {
966   struct bundle *bundle = ipcp->fsm.bundle;
967   struct iface *iface = bundle->iface;
968   struct in_addr myaddr, peer;
969   unsigned n;
970 
971   if (iplist_isvalid(&ipcp->cfg.peer_list)) {
972     ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
973     if (ip.s_addr == INADDR_ANY ||
974         iplist_ip2pos(&ipcp->cfg.peer_list, ip) < 0 ||
975         !ipcp_SetIPaddress(ipcp, myaddr, ip)) {
976       log_Printf(LogIPCP, "%s: Address invalid or already in use\n",
977                  inet_ntoa(ip));
978       /*
979        * If we've already had a valid address configured for the peer,
980        * try NAKing with that so that we don't have to upset things
981        * too much.
982        */
983       for (n = 0; n < iface->addrs; n++) {
984         if (!ncpaddr_getip4(&iface->addr[n].peer, &peer))
985           continue;
986         if (iplist_ip2pos(&ipcp->cfg.peer_list, peer) >= 0) {
987           ipcp->peer_ip = peer;
988           break;
989         }
990       }
991 
992       if (n == iface->addrs) {
993         /* Just pick an IP number from our list */
994         ipcp->peer_ip = ChooseHisAddr(bundle, myaddr);
995       }
996 
997       if (ipcp->peer_ip.s_addr == INADDR_ANY) {
998         *dec->rejend++ = TY_IPADDR;
999         *dec->rejend++ = 6;
1000         memcpy(dec->rejend, &ip.s_addr, 4);
1001         dec->rejend += 4;
1002       } else {
1003         *dec->nakend++ = TY_IPADDR;
1004         *dec->nakend++ = 6;
1005         memcpy(dec->nakend, &ipcp->peer_ip.s_addr, 4);
1006         dec->nakend += 4;
1007       }
1008       return;
1009     }
1010   } else if (ip.s_addr == INADDR_ANY ||
1011              !ncprange_containsip4(&ipcp->cfg.peer_range, ip)) {
1012     /*
1013      * If the destination address is not acceptable, NAK with what we
1014      * want to use.
1015      */
1016     *dec->nakend++ = TY_IPADDR;
1017     *dec->nakend++ = 6;
1018     for (n = 0; n < iface->addrs; n++)
1019       if (ncprange_contains(&ipcp->cfg.peer_range, &iface->addr[n].peer)) {
1020         /* We prefer the already-configured address */
1021         ncpaddr_getip4addr(&iface->addr[n].peer, (u_int32_t *)dec->nakend);
1022         break;
1023       }
1024 
1025     if (n == iface->addrs)
1026       memcpy(dec->nakend, &ipcp->peer_ip.s_addr, 4);
1027 
1028     dec->nakend += 4;
1029     return;
1030   }
1031 
1032   ipcp->peer_ip = ip;
1033   *dec->ackend++ = TY_IPADDR;
1034   *dec->ackend++ = 6;
1035   memcpy(dec->ackend, &ip.s_addr, 4);
1036   dec->ackend += 4;
1037 }
1038 
1039 static void
1040 IpcpDecodeConfig(struct fsm *fp, u_char *cp, u_char *end, int mode_type,
1041                  struct fsm_decode *dec)
1042 {
1043   /* Deal with incoming PROTO_IPCP */
1044   struct ncpaddr ncpaddr;
1045   struct ipcp *ipcp = fsm2ipcp(fp);
1046   int gotdnsnak;
1047   u_int32_t compproto;
1048   struct compreq *pcomp;
1049   struct in_addr ipaddr, dstipaddr, have_ip;
1050   char tbuff[100], tbuff2[100];
1051   struct fsm_opt *opt, nak;
1052 
1053   gotdnsnak = 0;
1054 
1055   while (end - cp >= (int)sizeof(opt->hdr)) {
1056     if ((opt = fsm_readopt(&cp)) == NULL)
1057       break;
1058 
1059     snprintf(tbuff, sizeof tbuff, " %s[%d]", protoname(opt->hdr.id),
1060              opt->hdr.len);
1061 
1062     switch (opt->hdr.id) {
1063     case TY_IPADDR:		/* RFC1332 */
1064       memcpy(&ipaddr.s_addr, opt->data, 4);
1065       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1066 
1067       switch (mode_type) {
1068       case MODE_REQ:
1069         ipcp->peer_req = 1;
1070         ipcp_ValidateReq(ipcp, ipaddr, dec);
1071         break;
1072 
1073       case MODE_NAK:
1074         if (ncprange_containsip4(&ipcp->cfg.my_range, ipaddr)) {
1075           /* Use address suggested by peer */
1076           snprintf(tbuff2, sizeof tbuff2, "%s changing address: %s ", tbuff,
1077                    inet_ntoa(ipcp->my_ip));
1078           log_Printf(LogIPCP, "%s --> %s\n", tbuff2, inet_ntoa(ipaddr));
1079           ipcp->my_ip = ipaddr;
1080           ncpaddr_setip4(&ncpaddr, ipcp->my_ip);
1081           bundle_AdjustFilters(fp->bundle, &ncpaddr, NULL);
1082         } else {
1083           log_Printf(log_IsKept(LogIPCP) ? LogIPCP : LogPHASE,
1084                     "%s: Unacceptable address!\n", inet_ntoa(ipaddr));
1085           fsm_Close(&ipcp->fsm);
1086         }
1087         break;
1088 
1089       case MODE_REJ:
1090         ipcp->peer_reject |= (1 << opt->hdr.id);
1091         break;
1092       }
1093       break;
1094 
1095     case TY_COMPPROTO:
1096       pcomp = (struct compreq *)opt->data;
1097       compproto = (ntohs(pcomp->proto) << 16) + ((int)pcomp->slots << 8) +
1098                   pcomp->compcid;
1099       log_Printf(LogIPCP, "%s %s\n", tbuff, vj2asc(compproto));
1100 
1101       switch (mode_type) {
1102       case MODE_REQ:
1103         if (!IsAccepted(ipcp->cfg.vj.neg))
1104           fsm_rej(dec, opt);
1105         else {
1106           switch (opt->hdr.len) {
1107           case 4:		/* RFC1172 */
1108             if (ntohs(pcomp->proto) == PROTO_VJCOMP) {
1109               log_Printf(LogWARN, "Peer is speaking RFC1172 compression "
1110                          "protocol !\n");
1111               ipcp->heis1172 = 1;
1112               ipcp->peer_compproto = compproto;
1113               fsm_ack(dec, opt);
1114             } else {
1115               pcomp->proto = htons(PROTO_VJCOMP);
1116               nak.hdr.id = TY_COMPPROTO;
1117               nak.hdr.len = 4;
1118               memcpy(nak.data, &pcomp, 2);
1119               fsm_nak(dec, &nak);
1120             }
1121             break;
1122           case 6:		/* RFC1332 */
1123             if (ntohs(pcomp->proto) == PROTO_VJCOMP) {
1124 	      /* We know pcomp->slots' max value == MAX_VJ_STATES */
1125               if (pcomp->slots >= MIN_VJ_STATES) {
1126                 /* Ok, we can do that */
1127                 ipcp->peer_compproto = compproto;
1128                 ipcp->heis1172 = 0;
1129                 fsm_ack(dec, opt);
1130               } else {
1131                 /* Get as close as we can to what he wants */
1132                 ipcp->heis1172 = 0;
1133                 pcomp->slots = MIN_VJ_STATES;
1134                 nak.hdr.id = TY_COMPPROTO;
1135                 nak.hdr.len = 4;
1136                 memcpy(nak.data, &pcomp, 2);
1137                 fsm_nak(dec, &nak);
1138               }
1139             } else {
1140               /* What we really want */
1141               pcomp->proto = htons(PROTO_VJCOMP);
1142               pcomp->slots = DEF_VJ_STATES;
1143               pcomp->compcid = 1;
1144               nak.hdr.id = TY_COMPPROTO;
1145               nak.hdr.len = 6;
1146               memcpy(nak.data, &pcomp, sizeof pcomp);
1147               fsm_nak(dec, &nak);
1148             }
1149             break;
1150           default:
1151             fsm_rej(dec, opt);
1152             break;
1153           }
1154         }
1155         break;
1156 
1157       case MODE_NAK:
1158         if (ntohs(pcomp->proto) == PROTO_VJCOMP) {
1159 	  /* We know pcomp->slots' max value == MAX_VJ_STATES */
1160           if (pcomp->slots < MIN_VJ_STATES)
1161             pcomp->slots = MIN_VJ_STATES;
1162           compproto = (ntohs(pcomp->proto) << 16) + (pcomp->slots << 8) +
1163                       pcomp->compcid;
1164         } else
1165           compproto = 0;
1166         log_Printf(LogIPCP, "%s changing compproto: %08x --> %08x\n",
1167                    tbuff, ipcp->my_compproto, compproto);
1168         ipcp->my_compproto = compproto;
1169         break;
1170 
1171       case MODE_REJ:
1172         ipcp->peer_reject |= (1 << opt->hdr.id);
1173         break;
1174       }
1175       break;
1176 
1177     case TY_IPADDRS:		/* RFC1172 */
1178       memcpy(&ipaddr.s_addr, opt->data, 4);
1179       memcpy(&dstipaddr.s_addr, opt->data + 4, 4);
1180       snprintf(tbuff2, sizeof tbuff2, "%s %s,", tbuff, inet_ntoa(ipaddr));
1181       log_Printf(LogIPCP, "%s %s\n", tbuff2, inet_ntoa(dstipaddr));
1182 
1183       switch (mode_type) {
1184       case MODE_REQ:
1185         fsm_rej(dec, opt);
1186         break;
1187 
1188       case MODE_NAK:
1189       case MODE_REJ:
1190         break;
1191       }
1192       break;
1193 
1194     case TY_PRIMARY_DNS:	/* DNS negotiation (rfc1877) */
1195     case TY_SECONDARY_DNS:
1196       memcpy(&ipaddr.s_addr, opt->data, 4);
1197       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1198 
1199       switch (mode_type) {
1200       case MODE_REQ:
1201         if (!IsAccepted(ipcp->cfg.ns.dns_neg)) {
1202           ipcp->my_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1203           fsm_rej(dec, opt);
1204           break;
1205         }
1206         have_ip = ipcp->ns.dns[opt->hdr.id == TY_PRIMARY_DNS ? 0 : 1];
1207 
1208         if (opt->hdr.id == TY_PRIMARY_DNS && ipaddr.s_addr != have_ip.s_addr &&
1209             ipaddr.s_addr == ipcp->ns.dns[1].s_addr) {
1210           /* Swap 'em 'round */
1211           ipcp->ns.dns[0] = ipcp->ns.dns[1];
1212           ipcp->ns.dns[1] = have_ip;
1213           have_ip = ipcp->ns.dns[0];
1214         }
1215 
1216         if (ipaddr.s_addr != have_ip.s_addr) {
1217           /*
1218            * The client has got the DNS stuff wrong (first request) so
1219            * we'll tell 'em how it is
1220            */
1221           nak.hdr.id = opt->hdr.id;
1222           nak.hdr.len = 6;
1223           memcpy(nak.data, &have_ip.s_addr, 4);
1224           fsm_nak(dec, &nak);
1225         } else {
1226           /*
1227            * Otherwise they have it right (this time) so we send an ack packet
1228            * back confirming it... end of story
1229            */
1230           fsm_ack(dec, opt);
1231         }
1232         break;
1233 
1234       case MODE_NAK:
1235         if (IsEnabled(ipcp->cfg.ns.dns_neg)) {
1236           gotdnsnak = 1;
1237           memcpy(&ipcp->ns.dns[opt->hdr.id == TY_PRIMARY_DNS ? 0 : 1].s_addr,
1238                  opt->data, 4);
1239         }
1240         break;
1241 
1242       case MODE_REJ:		/* Can't do much, stop asking */
1243         ipcp->peer_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1244         break;
1245       }
1246       break;
1247 
1248     case TY_PRIMARY_NBNS:	/* M$ NetBIOS nameserver hack (rfc1877) */
1249     case TY_SECONDARY_NBNS:
1250       memcpy(&ipaddr.s_addr, opt->data, 4);
1251       log_Printf(LogIPCP, "%s %s\n", tbuff, inet_ntoa(ipaddr));
1252 
1253       switch (mode_type) {
1254       case MODE_REQ:
1255         have_ip.s_addr =
1256           ipcp->cfg.ns.nbns[opt->hdr.id == TY_PRIMARY_NBNS ? 0 : 1].s_addr;
1257 
1258         if (have_ip.s_addr == INADDR_ANY) {
1259           log_Printf(LogIPCP, "NBNS REQ - rejected - nbns not set\n");
1260           ipcp->my_reject |= (1 << (opt->hdr.id - TY_ADJUST_NS));
1261           fsm_rej(dec, opt);
1262           break;
1263         }
1264 
1265         if (ipaddr.s_addr != have_ip.s_addr) {
1266           nak.hdr.id = opt->hdr.id;
1267           nak.hdr.len = 6;
1268           memcpy(nak.data, &have_ip.s_addr, 4);
1269           fsm_nak(dec, &nak);
1270         } else
1271           fsm_ack(dec, opt);
1272         break;
1273 
1274       case MODE_NAK:
1275         log_Printf(LogIPCP, "MS NBNS req %d - NAK??\n", opt->hdr.id);
1276         break;
1277 
1278       case MODE_REJ:
1279         log_Printf(LogIPCP, "MS NBNS req %d - REJ??\n", opt->hdr.id);
1280         break;
1281       }
1282       break;
1283 
1284     default:
1285       if (mode_type != MODE_NOP) {
1286         ipcp->my_reject |= (1 << opt->hdr.id);
1287         fsm_rej(dec, opt);
1288       }
1289       break;
1290     }
1291   }
1292 
1293   if (gotdnsnak) {
1294     if (ipcp->ns.writable) {
1295       log_Printf(LogDEBUG, "Updating resolver\n");
1296       if (!ipcp_WriteDNS(ipcp)) {
1297         ipcp->peer_reject |= (1 << (TY_PRIMARY_DNS - TY_ADJUST_NS));
1298         ipcp->peer_reject |= (1 << (TY_SECONDARY_DNS - TY_ADJUST_NS));
1299       } else
1300         bundle_AdjustDNS(fp->bundle);
1301     } else {
1302       log_Printf(LogDEBUG, "Not updating resolver (readonly)\n");
1303       bundle_AdjustDNS(fp->bundle);
1304     }
1305   }
1306 
1307   if (mode_type != MODE_NOP) {
1308     if (mode_type == MODE_REQ && !ipcp->peer_req) {
1309       if (dec->rejend == dec->rej && dec->nakend == dec->nak) {
1310         /*
1311          * Pretend the peer has requested an IP.
1312          * We do this to ensure that we only send one NAK if the only
1313          * reason for the NAK is because the peer isn't sending a
1314          * TY_IPADDR REQ.  This stops us from repeatedly trying to tell
1315          * the peer that we have to have an IP address on their end.
1316          */
1317         ipcp->peer_req = 1;
1318       }
1319       ipaddr.s_addr = INADDR_ANY;
1320       ipcp_ValidateReq(ipcp, ipaddr, dec);
1321     }
1322     fsm_opt_normalise(dec);
1323   }
1324 }
1325 
1326 extern struct mbuf *
1327 ipcp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
1328 {
1329   /* Got PROTO_IPCP from link */
1330   m_settype(bp, MB_IPCPIN);
1331   if (bundle_Phase(bundle) == PHASE_NETWORK)
1332     fsm_Input(&bundle->ncp.ipcp.fsm, bp);
1333   else {
1334     if (bundle_Phase(bundle) < PHASE_NETWORK)
1335       log_Printf(LogIPCP, "%s: Error: Unexpected IPCP in phase %s (ignored)\n",
1336                  l->name, bundle_PhaseName(bundle));
1337     m_freem(bp);
1338   }
1339   return NULL;
1340 }
1341 
1342 int
1343 ipcp_UseHisIPaddr(struct bundle *bundle, struct in_addr hisaddr)
1344 {
1345   struct ipcp *ipcp = &bundle->ncp.ipcp;
1346   struct in_addr myaddr;
1347 
1348   memset(&ipcp->cfg.peer_range, '\0', sizeof ipcp->cfg.peer_range);
1349   iplist_reset(&ipcp->cfg.peer_list);
1350   ipcp->peer_ip = hisaddr;
1351   ncprange_setip4host(&ipcp->cfg.peer_range, hisaddr);
1352   ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
1353 
1354   return ipcp_SetIPaddress(ipcp, myaddr, hisaddr);
1355 }
1356 
1357 int
1358 ipcp_UseHisaddr(struct bundle *bundle, const char *hisaddr, int setaddr)
1359 {
1360   struct in_addr myaddr;
1361   struct ncp *ncp = &bundle->ncp;
1362   struct ipcp *ipcp = &ncp->ipcp;
1363   struct ncpaddr ncpaddr;
1364 
1365   /* Use `hisaddr' for the peers address (set iface if `setaddr') */
1366   memset(&ipcp->cfg.peer_range, '\0', sizeof ipcp->cfg.peer_range);
1367   iplist_reset(&ipcp->cfg.peer_list);
1368   if (strpbrk(hisaddr, ",-")) {
1369     iplist_setsrc(&ipcp->cfg.peer_list, hisaddr);
1370     if (iplist_isvalid(&ipcp->cfg.peer_list)) {
1371       iplist_setrandpos(&ipcp->cfg.peer_list);
1372       ipcp->peer_ip = ChooseHisAddr(bundle, ipcp->my_ip);
1373       if (ipcp->peer_ip.s_addr == INADDR_ANY) {
1374         log_Printf(LogWARN, "%s: None available !\n", ipcp->cfg.peer_list.src);
1375         return 0;
1376       }
1377       ncprange_setip4host(&ipcp->cfg.peer_range, ipcp->peer_ip);
1378     } else {
1379       log_Printf(LogWARN, "%s: Invalid range !\n", hisaddr);
1380       return 0;
1381     }
1382   } else if (ncprange_aton(&ipcp->cfg.peer_range, ncp, hisaddr) != 0) {
1383     if (ncprange_family(&ipcp->cfg.my_range) != AF_INET) {
1384       log_Printf(LogWARN, "%s: Not an AF_INET address !\n", hisaddr);
1385       return 0;
1386     }
1387     ncprange_getip4addr(&ipcp->cfg.my_range, &myaddr);
1388     ncprange_getip4addr(&ipcp->cfg.peer_range, &ipcp->peer_ip);
1389 
1390     if (setaddr && !ipcp_SetIPaddress(ipcp, myaddr, ipcp->peer_ip))
1391       return 0;
1392   } else
1393     return 0;
1394 
1395   ncpaddr_setip4(&ncpaddr, ipcp->peer_ip);
1396   bundle_AdjustFilters(bundle, NULL, &ncpaddr);
1397 
1398   return 1;	/* Ok */
1399 }
1400 
1401 struct in_addr
1402 addr2mask(struct in_addr addr)
1403 {
1404   u_int32_t haddr = ntohl(addr.s_addr);
1405 
1406   haddr = IN_CLASSA(haddr) ? IN_CLASSA_NET :
1407           IN_CLASSB(haddr) ? IN_CLASSB_NET :
1408           IN_CLASSC_NET;
1409   addr.s_addr = htonl(haddr);
1410 
1411   return addr;
1412 }
1413 
1414 size_t
1415 ipcp_QueueLen(struct ipcp *ipcp)
1416 {
1417   struct mqueue *q;
1418   size_t result;
1419 
1420   result = 0;
1421   for (q = ipcp->Queue; q < ipcp->Queue + IPCP_QUEUES(ipcp); q++)
1422     result += q->len;
1423 
1424   return result;
1425 }
1426 
1427 int
1428 ipcp_PushPacket(struct ipcp *ipcp, struct link *l)
1429 {
1430   struct bundle *bundle = ipcp->fsm.bundle;
1431   struct mqueue *queue;
1432   struct mbuf *bp;
1433   int m_len;
1434   u_int32_t secs = 0;
1435   unsigned alivesecs = 0;
1436 
1437   if (ipcp->fsm.state != ST_OPENED)
1438     return 0;
1439 
1440   /*
1441    * If ccp is not open but is required, do nothing.
1442    */
1443   if (l->ccp.fsm.state != ST_OPENED && ccp_Required(&l->ccp)) {
1444     log_Printf(LogPHASE, "%s: Not transmitting... waiting for CCP\n", l->name);
1445     return 0;
1446   }
1447 
1448   queue = ipcp->Queue + IPCP_QUEUES(ipcp) - 1;
1449   do {
1450     if (queue->top) {
1451       bp = m_dequeue(queue);
1452       bp = mbuf_Read(bp, &secs, sizeof secs);
1453       bp = m_pullup(bp);
1454       m_len = m_length(bp);
1455       if (!FilterCheck(MBUF_CTOP(bp), AF_INET, &bundle->filter.alive,
1456                        &alivesecs)) {
1457         if (secs == 0)
1458           secs = alivesecs;
1459         bundle_StartIdleTimer(bundle, secs);
1460       }
1461       link_PushPacket(l, bp, bundle, 0, PROTO_IP);
1462       ipcp_AddOutOctets(ipcp, m_len);
1463       return 1;
1464     }
1465   } while (queue-- != ipcp->Queue);
1466 
1467   return 0;
1468 }
1469