tool/mbed/mbed-sdk/libraries/net/lwip/lwip/netif/ppp/ipcp.c

   1 /** In contrast to pppd 2.3.1, DNS support has been added, proxy-ARP and
   2     dial-on-demand has been stripped. */
   3 /*****************************************************************************
   4 * ipcp.c - Network PPP IP Control Protocol program file.
   5 *
   6 * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
   7 * portions Copyright (c) 1997 by Global Election Systems Inc.
   8 *
   9 * The authors hereby grant permission to use, copy, modify, distribute,
  10 * and license this software and its documentation for any purpose, provided
  11 * that existing copyright notices are retained in all copies and that this
  12 * notice and the following disclaimer are included verbatim in any
  13 * distributions. No written agreement, license, or royalty fee is required
  14 * for any of the authorized uses.
  15 *
  16 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
  17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19 * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26 *
  27 ******************************************************************************
  28 * REVISION HISTORY
  29 *
  30 * 03-01-01 Marc Boucher <marc@mbsi.ca>
  31 *   Ported to lwIP.
  32 * 97-12-08 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
  33 *   Original.
  34 *****************************************************************************/
  35 /*
  36  * ipcp.c - PPP IP Control Protocol.
  37  *
  38  * Copyright (c) 1989 Carnegie Mellon University.
  39  * All rights reserved.
  40  *
  41  * Redistribution and use in source and binary forms are permitted
  42  * provided that the above copyright notice and this paragraph are
  43  * duplicated in all such forms and that any documentation,
  44  * advertising materials, and other materials related to such
  45  * distribution and use acknowledge that the software was developed
  46  * by Carnegie Mellon University.  The name of the
  47  * University may not be used to endorse or promote products derived
  48  * from this software without specific prior written permission.
  49  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  50  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  51  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  52  */
  53
  54 #include "lwip/opt.h"
  55
  56 #if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
  57
  58 #include "ppp.h"
  59 #include "pppdebug.h"
  60
  61 #include "auth.h"
  62 #include "fsm.h"
  63 #include "vj.h"
  64 #include "ipcp.h"
  65
  66 #include "lwip/inet.h"
  67
  68 #include <string.h>
  69
  70 /* #define OLD_CI_ADDRS 1 */ /* Support deprecated address negotiation. */
  71
  72 /* global vars */
  73 ipcp_options ipcp_wantoptions[NUM_PPP];  /* Options that we want to request */
  74 ipcp_options ipcp_gotoptions[NUM_PPP];   /* Options that peer ack'd */
  75 ipcp_options ipcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */
  76 ipcp_options ipcp_hisoptions[NUM_PPP];   /* Options that we ack'd */
  77
  78 /* local vars */
  79 static int default_route_set[NUM_PPP]; /* Have set up a default route */
  80 static int cis_received[NUM_PPP];      /* # Conf-Reqs received */
  81
  82
  83 /*
  84  * Callbacks for fsm code.  (CI = Configuration Information)
  85  */
  86 static void ipcp_resetci (fsm *);                     /* Reset our CI */
  87 static int  ipcp_cilen (fsm *);                       /* Return length of our CI */
  88 static void ipcp_addci (fsm *, u_char *, int *);      /* Add our CI */
  89 static int  ipcp_ackci (fsm *, u_char *, int);        /* Peer ack'd our CI */
  90 static int  ipcp_nakci (fsm *, u_char *, int);        /* Peer nak'd our CI */
  91 static int  ipcp_rejci (fsm *, u_char *, int);        /* Peer rej'd our CI */
  92 static int  ipcp_reqci (fsm *, u_char *, int *, int); /* Rcv CI */
  93 static void ipcp_up (fsm *);                          /* We're UP */
  94 static void ipcp_down (fsm *);                        /* We're DOWN */
  95 #if PPP_ADDITIONAL_CALLBACKS
  96 static void ipcp_script (fsm *, char *); /* Run an up/down script */
  97 #endif
  98 static void ipcp_finished (fsm *);                    /* Don't need lower layer */
  99
 100
 101 fsm ipcp_fsm[NUM_PPP]; /* IPCP fsm structure */
 102
 103
 104 static fsm_callbacks ipcp_callbacks = { /* IPCP callback routines */
 105   ipcp_resetci,  /* Reset our Configuration Information */
 106   ipcp_cilen,    /* Length of our Configuration Information */
 107   ipcp_addci,    /* Add our Configuration Information */
 108   ipcp_ackci,    /* ACK our Configuration Information */
 109   ipcp_nakci,    /* NAK our Configuration Information */
 110   ipcp_rejci,    /* Reject our Configuration Information */
 111   ipcp_reqci,    /* Request peer's Configuration Information */
 112   ipcp_up,       /* Called when fsm reaches LS_OPENED state */
 113   ipcp_down,     /* Called when fsm leaves LS_OPENED state */
 114   NULL,          /* Called when we want the lower layer up */
 115   ipcp_finished, /* Called when we want the lower layer down */
 116   NULL,          /* Called when Protocol-Reject received */
 117   NULL,          /* Retransmission is necessary */
 118   NULL,          /* Called to handle protocol-specific codes */
 119   "IPCP"         /* String name of protocol */
 120 };
 121
 122 /*
 123  * Protocol entry points from main code.
 124  */
 125 static void ipcp_init (int);
 126 static void ipcp_open (int);
 127 static void ipcp_close (int, char *);
 128 static void ipcp_lowerup (int);
 129 static void ipcp_lowerdown (int);
 130 static void ipcp_input (int, u_char *, int);
 131 static void ipcp_protrej (int);
 132
 133
 134 struct protent ipcp_protent = {
 135   PPP_IPCP,
 136   ipcp_init,
 137   ipcp_input,
 138   ipcp_protrej,
 139   ipcp_lowerup,
 140   ipcp_lowerdown,
 141   ipcp_open,
 142   ipcp_close,
 143 #if PPP_ADDITIONAL_CALLBACKS
 144   ipcp_printpkt,
 145   NULL,
 146 #endif /* PPP_ADDITIONAL_CALLBACKS */
 147   1,
 148   "IPCP",
 149 #if PPP_ADDITIONAL_CALLBACKS
 150   ip_check_options,
 151   NULL,
 152   ip_active_pkt
 153 #endif /* PPP_ADDITIONAL_CALLBACKS */
 154 };
 155
 156 static void ipcp_clear_addrs (int);
 157
 158 /*
 159  * Lengths of configuration options.
 160  */
 161 #define CILEN_VOID     2
 162 #define CILEN_COMPRESS 4  /* min length for compression protocol opt. */
 163 #define CILEN_VJ       6  /* length for RFC1332 Van-Jacobson opt. */
 164 #define CILEN_ADDR     6  /* new-style single address option */
 165 #define CILEN_ADDRS    10 /* old-style dual address option */
 166
 167
 168 #define CODENAME(x) ((x) == CONFACK ? "ACK" : \
 169                      (x) == CONFNAK ? "NAK" : "REJ")
 170
 171
 172 /*
 173  * ipcp_init - Initialize IPCP.
 174  */
 175 static void
 176 ipcp_init(int unit)
 177 {
 178   fsm           *f = &ipcp_fsm[unit];
 179   ipcp_options *wo = &ipcp_wantoptions[unit];
 180   ipcp_options *ao = &ipcp_allowoptions[unit];
 181
 182   f->unit      = unit;
 183   f->protocol  = PPP_IPCP;
 184   f->callbacks = &ipcp_callbacks;
 185   fsm_init(&ipcp_fsm[unit]);
 186
 187   memset(wo, 0, sizeof(*wo));
 188   memset(ao, 0, sizeof(*ao));
 189
 190   wo->neg_addr      = 1;
 191   wo->ouraddr       = 0;
 192 #if VJ_SUPPORT
 193   wo->neg_vj        = 1;
 194 #else  /* VJ_SUPPORT */
 195   wo->neg_vj        = 0;
 196 #endif /* VJ_SUPPORT */
 197   wo->vj_protocol   = IPCP_VJ_COMP;
 198   wo->maxslotindex  = MAX_SLOTS - 1;
 199   wo->cflag         = 0;
 200   wo->default_route = 1;
 201
 202   ao->neg_addr      = 1;
 203 #if VJ_SUPPORT
 204   ao->neg_vj        = 1;
 205 #else  /* VJ_SUPPORT */
 206   ao->neg_vj        = 0;
 207 #endif /* VJ_SUPPORT */
 208   ao->maxslotindex  = MAX_SLOTS - 1;
 209   ao->cflag         = 1;
 210   ao->default_route = 1;
 211 }
 212
 213
 214 /*
 215  * ipcp_open - IPCP is allowed to come up.
 216  */
 217 static void
 218 ipcp_open(int unit)
 219 {
 220   fsm_open(&ipcp_fsm[unit]);
 221 }
 222
 223
 224 /*
 225  * ipcp_close - Take IPCP down.
 226  */
 227 static void
 228 ipcp_close(int unit, char *reason)
 229 {
 230   fsm_close(&ipcp_fsm[unit], reason);
 231 }
 232
 233
 234 /*
 235  * ipcp_lowerup - The lower layer is up.
 236  */
 237 static void
 238 ipcp_lowerup(int unit)
 239 {
 240   fsm_lowerup(&ipcp_fsm[unit]);
 241 }
 242
 243
 244 /*
 245  * ipcp_lowerdown - The lower layer is down.
 246  */
 247 static void
 248 ipcp_lowerdown(int unit)
 249 {
 250   fsm_lowerdown(&ipcp_fsm[unit]);
 251 }
 252
 253
 254 /*
 255  * ipcp_input - Input IPCP packet.
 256  */
 257 static void
 258 ipcp_input(int unit, u_char *p, int len)
 259 {
 260   fsm_input(&ipcp_fsm[unit], p, len);
 261 }
 262
 263
 264 /*
 265  * ipcp_protrej - A Protocol-Reject was received for IPCP.
 266  *
 267  * Pretend the lower layer went down, so we shut up.
 268  */
 269 static void
 270 ipcp_protrej(int unit)
 271 {
 272   fsm_lowerdown(&ipcp_fsm[unit]);
 273 }
 274
 275
 276 /*
 277  * ipcp_resetci - Reset our CI.
 278  */
 279 static void
 280 ipcp_resetci(fsm *f)
 281 {
 282   ipcp_options *wo = &ipcp_wantoptions[f->unit];
 283
 284   wo->req_addr = wo->neg_addr && ipcp_allowoptions[f->unit].neg_addr;
 285   if (wo->ouraddr == 0) {
 286     wo->accept_local = 1;
 287   }
 288   if (wo->hisaddr == 0) {
 289     wo->accept_remote = 1;
 290   }
 291   /* Request DNS addresses from the peer */
 292   wo->req_dns1 = ppp_settings.usepeerdns;
 293   wo->req_dns2 = ppp_settings.usepeerdns;
 294   ipcp_gotoptions[f->unit] = *wo;
 295   cis_received[f->unit] = 0;
 296 }
 297
 298
 299 /*
 300  * ipcp_cilen - Return length of our CI.
 301  */
 302 static int
 303 ipcp_cilen(fsm *f)
 304 {
 305   ipcp_options *go = &ipcp_gotoptions[f->unit];
 306   ipcp_options *wo = &ipcp_wantoptions[f->unit];
 307   ipcp_options *ho = &ipcp_hisoptions[f->unit];
 308
 309 #define LENCIVJ(neg, old)   (neg ? (old? CILEN_COMPRESS : CILEN_VJ) : 0)
 310 #define LENCIADDR(neg, old) (neg ? (old? CILEN_ADDRS : CILEN_ADDR) : 0)
 311 #define LENCIDNS(neg)       (neg ? (CILEN_ADDR) : 0)
 312
 313   /*
 314    * First see if we want to change our options to the old
 315    * forms because we have received old forms from the peer.
 316    */
 317   if (wo->neg_addr && !go->neg_addr && !go->old_addrs) {
 318     /* use the old style of address negotiation */
 319     go->neg_addr = 1;
 320     go->old_addrs = 1;
 321   }
 322   if (wo->neg_vj && !go->neg_vj && !go->old_vj) {
 323     /* try an older style of VJ negotiation */
 324     if (cis_received[f->unit] == 0) {
 325       /* keep trying the new style until we see some CI from the peer */
 326       go->neg_vj = 1;
 327     } else {
 328       /* use the old style only if the peer did */
 329       if (ho->neg_vj && ho->old_vj) {
 330         go->neg_vj = 1;
 331         go->old_vj = 1;
 332         go->vj_protocol = ho->vj_protocol;
 333       }
 334     }
 335   }
 336
 337   return (LENCIADDR(go->neg_addr, go->old_addrs) +
 338           LENCIVJ(go->neg_vj, go->old_vj) +
 339           LENCIDNS(go->req_dns1) +
 340           LENCIDNS(go->req_dns2));
 341 }
 342
 343
 344 /*
 345  * ipcp_addci - Add our desired CIs to a packet.
 346  */
 347 static void
 348 ipcp_addci(fsm *f, u_char *ucp, int *lenp)
 349 {
 350   ipcp_options *go = &ipcp_gotoptions[f->unit];
 351   int len = *lenp;
 352
 353 #define ADDCIVJ(opt, neg, val, old, maxslotindex, cflag) \
 354   if (neg) { \
 355     int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \
 356     if (len >= vjlen) { \
 357       PUTCHAR(opt, ucp); \
 358       PUTCHAR(vjlen, ucp); \
 359       PUTSHORT(val, ucp); \
 360       if (!old) { \
 361         PUTCHAR(maxslotindex, ucp); \
 362         PUTCHAR(cflag, ucp); \
 363       } \
 364       len -= vjlen; \
 365     } else { \
 366       neg = 0; \
 367     } \
 368   }
 369
 370 #define ADDCIADDR(opt, neg, old, val1, val2) \
 371   if (neg) { \
 372     int addrlen = (old? CILEN_ADDRS: CILEN_ADDR); \
 373     if (len >= addrlen) { \
 374       u32_t l; \
 375       PUTCHAR(opt, ucp); \
 376       PUTCHAR(addrlen, ucp); \
 377       l = ntohl(val1); \
 378       PUTLONG(l, ucp); \
 379       if (old) { \
 380         l = ntohl(val2); \
 381         PUTLONG(l, ucp); \
 382       } \
 383       len -= addrlen; \
 384     } else { \
 385       neg = 0; \
 386     } \
 387   }
 388
 389 #define ADDCIDNS(opt, neg, addr) \
 390   if (neg) { \
 391     if (len >= CILEN_ADDR) { \
 392       u32_t l; \
 393       PUTCHAR(opt, ucp); \
 394       PUTCHAR(CILEN_ADDR, ucp); \
 395       l = ntohl(addr); \
 396       PUTLONG(l, ucp); \
 397       len -= CILEN_ADDR; \
 398     } else { \
 399       neg = 0; \
 400     } \
 401   }
 402
 403   ADDCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), go->neg_addr,
 404       go->old_addrs, go->ouraddr, go->hisaddr);
 405
 406   ADDCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj,
 407       go->maxslotindex, go->cflag);
 408
 409   ADDCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]);
 410
 411   ADDCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
 412
 413   *lenp -= len;
 414 }
 415
 416
 417 /*
 418  * ipcp_ackci - Ack our CIs.
 419  *
 420  * Returns:
 421  *  0 - Ack was bad.
 422  *  1 - Ack was good.
 423  */
 424 static int
 425 ipcp_ackci(fsm *f, u_char *p, int len)
 426 {
 427   ipcp_options *go = &ipcp_gotoptions[f->unit];
 428   u_short cilen, citype, cishort;
 429   u32_t cilong;
 430   u_char cimaxslotindex, cicflag;
 431
 432   /*
 433    * CIs must be in exactly the same order that we sent...
 434    * Check packet length and CI length at each step.
 435    * If we find any deviations, then this packet is bad.
 436    */
 437
 438 #define ACKCIVJ(opt, neg, val, old, maxslotindex, cflag) \
 439   if (neg) { \
 440     int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \
 441     if ((len -= vjlen) < 0) { \
 442       goto bad; \
 443     } \
 444     GETCHAR(citype, p); \
 445     GETCHAR(cilen, p); \
 446     if (cilen != vjlen || \
 447         citype != opt) { \
 448       goto bad; \
 449     } \
 450     GETSHORT(cishort, p); \
 451     if (cishort != val) { \
 452       goto bad; \
 453     } \
 454     if (!old) { \
 455       GETCHAR(cimaxslotindex, p); \
 456       if (cimaxslotindex != maxslotindex) { \
 457         goto bad; \
 458       } \
 459       GETCHAR(cicflag, p); \
 460       if (cicflag != cflag) { \
 461         goto bad; \
 462       } \
 463     } \
 464   }
 465
 466 #define ACKCIADDR(opt, neg, old, val1, val2) \
 467   if (neg) { \
 468     int addrlen = (old? CILEN_ADDRS: CILEN_ADDR); \
 469     u32_t l; \
 470     if ((len -= addrlen) < 0) { \
 471       goto bad; \
 472     } \
 473     GETCHAR(citype, p); \
 474     GETCHAR(cilen, p); \
 475     if (cilen != addrlen || \
 476         citype != opt) { \
 477       goto bad; \
 478     } \
 479     GETLONG(l, p); \
 480     cilong = htonl(l); \
 481     if (val1 != cilong) { \
 482       goto bad; \
 483     } \
 484     if (old) { \
 485       GETLONG(l, p); \
 486       cilong = htonl(l); \
 487       if (val2 != cilong) { \
 488         goto bad; \
 489       } \
 490     } \
 491   }
 492
 493 #define ACKCIDNS(opt, neg, addr) \
 494   if (neg) { \
 495     u32_t l; \
 496     if ((len -= CILEN_ADDR) < 0) { \
 497       goto bad; \
 498     } \
 499     GETCHAR(citype, p); \
 500     GETCHAR(cilen, p); \
 501     if (cilen != CILEN_ADDR || \
 502         citype != opt) { \
 503       goto bad; \
 504     } \
 505     GETLONG(l, p); \
 506     cilong = htonl(l); \
 507     if (addr != cilong) { \
 508       goto bad; \
 509     } \
 510   }
 511
 512   ACKCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), go->neg_addr,
 513         go->old_addrs, go->ouraddr, go->hisaddr);
 514
 515   ACKCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj,
 516       go->maxslotindex, go->cflag);
 517
 518   ACKCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]);
 519
 520   ACKCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
 521
 522   /*
 523    * If there are any remaining CIs, then this packet is bad.
 524    */
 525   if (len != 0) {
 526     goto bad;
 527   }
 528   return (1);
 529
 530 bad:
 531   IPCPDEBUG(LOG_INFO, ("ipcp_ackci: received bad Ack!\n"));
 532   return (0);
 533 }
 534
 535 /*
 536  * ipcp_nakci - Peer has sent a NAK for some of our CIs.
 537  * This should not modify any state if the Nak is bad
 538  * or if IPCP is in the LS_OPENED state.
 539  *
 540  * Returns:
 541  *  0 - Nak was bad.
 542  *  1 - Nak was good.
 543  */
 544 static int
 545 ipcp_nakci(fsm *f, u_char *p, int len)
 546 {
 547   ipcp_options *go = &ipcp_gotoptions[f->unit];
 548   u_char cimaxslotindex, cicflag;
 549   u_char citype, cilen, *next;
 550   u_short cishort;
 551   u32_t ciaddr1, ciaddr2, l, cidnsaddr;
 552   ipcp_options no;    /* options we've seen Naks for */
 553   ipcp_options try;    /* options to request next time */
 554
 555   BZERO(&no, sizeof(no));
 556   try = *go;
 557
 558   /*
 559    * Any Nak'd CIs must be in exactly the same order that we sent.
 560    * Check packet length and CI length at each step.
 561    * If we find any deviations, then this packet is bad.
 562    */
 563 #define NAKCIADDR(opt, neg, old, code) \
 564   if (go->neg && \
 565       len >= (cilen = (old? CILEN_ADDRS: CILEN_ADDR)) && \
 566       p[1] == cilen && \
 567       p[0] == opt) { \
 568     len -= cilen; \
 569     INCPTR(2, p); \
 570     GETLONG(l, p); \
 571     ciaddr1 = htonl(l); \
 572     if (old) { \
 573       GETLONG(l, p); \
 574       ciaddr2 = htonl(l); \
 575       no.old_addrs = 1; \
 576     } else { \
 577       ciaddr2 = 0; \
 578     } \
 579     no.neg = 1; \
 580     code \
 581   }
 582
 583 #define NAKCIVJ(opt, neg, code) \
 584   if (go->neg && \
 585       ((cilen = p[1]) == CILEN_COMPRESS || cilen == CILEN_VJ) && \
 586       len >= cilen && \
 587       p[0] == opt) { \
 588     len -= cilen; \
 589     INCPTR(2, p); \
 590     GETSHORT(cishort, p); \
 591     no.neg = 1; \
 592     code \
 593   }
 594
 595 #define NAKCIDNS(opt, neg, code) \
 596   if (go->neg && \
 597       ((cilen = p[1]) == CILEN_ADDR) && \
 598       len >= cilen && \
 599       p[0] == opt) { \
 600     len -= cilen; \
 601     INCPTR(2, p); \
 602     GETLONG(l, p); \
 603     cidnsaddr = htonl(l); \
 604     no.neg = 1; \
 605     code \
 606   }
 607
 608   /*
 609    * Accept the peer's idea of {our,his} address, if different
 610    * from our idea, only if the accept_{local,remote} flag is set.
 611    */
 612   NAKCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), neg_addr, go->old_addrs,
 613     if (go->accept_local && ciaddr1) { /* Do we know our address? */
 614       try.ouraddr = ciaddr1;
 615       IPCPDEBUG(LOG_INFO, ("local IP address %s\n",
 616            inet_ntoa(ciaddr1)));
 617     }
 618     if (go->accept_remote && ciaddr2) { /* Does he know his? */
 619       try.hisaddr = ciaddr2;
 620       IPCPDEBUG(LOG_INFO, ("remote IP address %s\n",
 621            inet_ntoa(ciaddr2)));
 622     }
 623   );
 624
 625   /*
 626    * Accept the peer's value of maxslotindex provided that it
 627    * is less than what we asked for.  Turn off slot-ID compression
 628    * if the peer wants.  Send old-style compress-type option if
 629    * the peer wants.
 630    */
 631   NAKCIVJ(CI_COMPRESSTYPE, neg_vj,
 632     if (cilen == CILEN_VJ) {
 633       GETCHAR(cimaxslotindex, p);
 634       GETCHAR(cicflag, p);
 635       if (cishort == IPCP_VJ_COMP) {
 636         try.old_vj = 0;
 637         if (cimaxslotindex < go->maxslotindex) {
 638           try.maxslotindex = cimaxslotindex;
 639         }
 640         if (!cicflag) {
 641           try.cflag = 0;
 642         }
 643       } else {
 644         try.neg_vj = 0;
 645       }
 646     } else {
 647       if (cishort == IPCP_VJ_COMP || cishort == IPCP_VJ_COMP_OLD) {
 648         try.old_vj = 1;
 649         try.vj_protocol = cishort;
 650       } else {
 651         try.neg_vj = 0;
 652       }
 653     }
 654   );
 655
 656   NAKCIDNS(CI_MS_DNS1, req_dns1,
 657       try.dnsaddr[0] = cidnsaddr;
 658         IPCPDEBUG(LOG_INFO, ("primary DNS address %s\n", inet_ntoa(cidnsaddr)));
 659       );
 660
 661   NAKCIDNS(CI_MS_DNS2, req_dns2,
 662       try.dnsaddr[1] = cidnsaddr;
 663         IPCPDEBUG(LOG_INFO, ("secondary DNS address %s\n", inet_ntoa(cidnsaddr)));
 664       );
 665
 666   /*
 667   * There may be remaining CIs, if the peer is requesting negotiation
 668   * on an option that we didn't include in our request packet.
 669   * If they want to negotiate about IP addresses, we comply.
 670   * If they want us to ask for compression, we refuse.
 671   */
 672   while (len > CILEN_VOID) {
 673     GETCHAR(citype, p);
 674     GETCHAR(cilen, p);
 675     if( (len -= cilen) < 0 ) {
 676       goto bad;
 677     }
 678     next = p + cilen - 2;
 679
 680     switch (citype) {
 681       case CI_COMPRESSTYPE:
 682         if (go->neg_vj || no.neg_vj ||
 683             (cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) {
 684           goto bad;
 685         }
 686         no.neg_vj = 1;
 687         break;
 688       case CI_ADDRS:
 689         if ((go->neg_addr && go->old_addrs) || no.old_addrs
 690             || cilen != CILEN_ADDRS) {
 691           goto bad;
 692         }
 693         try.neg_addr = 1;
 694         try.old_addrs = 1;
 695         GETLONG(l, p);
 696         ciaddr1 = htonl(l);
 697         if (ciaddr1 && go->accept_local) {
 698           try.ouraddr = ciaddr1;
 699         }
 700         GETLONG(l, p);
 701         ciaddr2 = htonl(l);
 702         if (ciaddr2 && go->accept_remote) {
 703           try.hisaddr = ciaddr2;
 704         }
 705         no.old_addrs = 1;
 706         break;
 707       case CI_ADDR:
 708         if (go->neg_addr || no.neg_addr || cilen != CILEN_ADDR) {
 709           goto bad;
 710         }
 711         try.old_addrs = 0;
 712         GETLONG(l, p);
 713         ciaddr1 = htonl(l);
 714         if (ciaddr1 && go->accept_local) {
 715           try.ouraddr = ciaddr1;
 716         }
 717         if (try.ouraddr != 0) {
 718           try.neg_addr = 1;
 719         }
 720         no.neg_addr = 1;
 721         break;
 722     }
 723     p = next;
 724   }
 725
 726   /* If there is still anything left, this packet is bad. */
 727   if (len != 0) {
 728     goto bad;
 729   }
 730
 731   /*
 732    * OK, the Nak is good.  Now we can update state.
 733    */
 734   if (f->state != LS_OPENED) {
 735     *go = try;
 736   }
 737
 738   return 1;
 739
 740 bad:
 741   IPCPDEBUG(LOG_INFO, ("ipcp_nakci: received bad Nak!\n"));
 742   return 0;
 743 }
 744
 745
 746 /*
 747  * ipcp_rejci - Reject some of our CIs.
 748  */
 749 static int
 750 ipcp_rejci(fsm *f, u_char *p, int len)
 751 {
 752   ipcp_options *go = &ipcp_gotoptions[f->unit];
 753   u_char cimaxslotindex, ciflag, cilen;
 754   u_short cishort;
 755   u32_t cilong;
 756   ipcp_options try;    /* options to request next time */
 757
 758   try = *go;
 759   /*
 760    * Any Rejected CIs must be in exactly the same order that we sent.
 761    * Check packet length and CI length at each step.
 762    * If we find any deviations, then this packet is bad.
 763    */
 764 #define REJCIADDR(opt, neg, old, val1, val2) \
 765   if (go->neg && \
 766       len >= (cilen = old? CILEN_ADDRS: CILEN_ADDR) && \
 767       p[1] == cilen && \
 768       p[0] == opt) { \
 769     u32_t l; \
 770     len -= cilen; \
 771     INCPTR(2, p); \
 772     GETLONG(l, p); \
 773     cilong = htonl(l); \
 774     /* Check rejected value. */ \
 775     if (cilong != val1) { \
 776       goto bad; \
 777     } \
 778     if (old) { \
 779       GETLONG(l, p); \
 780       cilong = htonl(l); \
 781       /* Check rejected value. */ \
 782       if (cilong != val2) { \
 783         goto bad; \
 784       } \
 785     } \
 786     try.neg = 0; \
 787   }
 788
 789 #define REJCIVJ(opt, neg, val, old, maxslot, cflag) \
 790   if (go->neg && \
 791       p[1] == (old? CILEN_COMPRESS : CILEN_VJ) && \
 792       len >= p[1] && \
 793       p[0] == opt) { \
 794     len -= p[1]; \
 795     INCPTR(2, p); \
 796     GETSHORT(cishort, p); \
 797     /* Check rejected value. */  \
 798     if (cishort != val) { \
 799       goto bad; \
 800     } \
 801     if (!old) { \
 802       GETCHAR(cimaxslotindex, p); \
 803       if (cimaxslotindex != maxslot) { \
 804         goto bad; \
 805       } \
 806       GETCHAR(ciflag, p); \
 807       if (ciflag != cflag) { \
 808         goto bad; \
 809       } \
 810     } \
 811     try.neg = 0; \
 812   }
 813
 814 #define REJCIDNS(opt, neg, dnsaddr) \
 815   if (go->neg && \
 816       ((cilen = p[1]) == CILEN_ADDR) && \
 817       len >= cilen && \
 818       p[0] == opt) { \
 819     u32_t l; \
 820     len -= cilen; \
 821     INCPTR(2, p); \
 822     GETLONG(l, p); \
 823     cilong = htonl(l); \
 824     /* Check rejected value. */ \
 825     if (cilong != dnsaddr) { \
 826       goto bad; \
 827     } \
 828     try.neg = 0; \
 829   }
 830
 831   REJCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), neg_addr,
 832         go->old_addrs, go->ouraddr, go->hisaddr);
 833
 834   REJCIVJ(CI_COMPRESSTYPE, neg_vj, go->vj_protocol, go->old_vj,
 835       go->maxslotindex, go->cflag);
 836
 837   REJCIDNS(CI_MS_DNS1, req_dns1, go->dnsaddr[0]);
 838
 839   REJCIDNS(CI_MS_DNS2, req_dns2, go->dnsaddr[1]);
 840
 841   /*
 842    * If there are any remaining CIs, then this packet is bad.
 843    */
 844   if (len != 0) {
 845     goto bad;
 846   }
 847   /*
 848    * Now we can update state.
 849    */
 850   if (f->state != LS_OPENED) {
 851     *go = try;
 852   }
 853   return 1;
 854
 855 bad:
 856   IPCPDEBUG(LOG_INFO, ("ipcp_rejci: received bad Reject!\n"));
 857   return 0;
 858 }
 859
 860
 861 /*
 862  * ipcp_reqci - Check the peer's requested CIs and send appropriate response.
 863  *
 864  * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified
 865  * appropriately.  If reject_if_disagree is non-zero, doesn't return
 866  * CONFNAK; returns CONFREJ if it can't return CONFACK.
 867  */
 868 static int
 869 ipcp_reqci(fsm *f, u_char *inp/* Requested CIs */,int *len/* Length of requested CIs */,int reject_if_disagree)
 870 {
 871   ipcp_options *wo = &ipcp_wantoptions[f->unit];
 872   ipcp_options *ho = &ipcp_hisoptions[f->unit];
 873   ipcp_options *ao = &ipcp_allowoptions[f->unit];
 874 #ifdef OLD_CI_ADDRS
 875   ipcp_options *go = &ipcp_gotoptions[f->unit];
 876 #endif
 877   u_char *cip, *next;     /* Pointer to current and next CIs */
 878   u_short cilen, citype;  /* Parsed len, type */
 879   u_short cishort;        /* Parsed short value */
 880   u32_t tl, ciaddr1;      /* Parsed address values */
 881 #ifdef OLD_CI_ADDRS
 882   u32_t ciaddr2;          /* Parsed address values */
 883 #endif
 884   int rc = CONFACK;       /* Final packet return code */
 885   int orc;                /* Individual option return code */
 886   u_char *p;              /* Pointer to next char to parse */
 887   u_char *ucp = inp;      /* Pointer to current output char */
 888   int l = *len;           /* Length left */
 889   u_char maxslotindex, cflag;
 890   int d;
 891
 892   cis_received[f->unit] = 1;
 893
 894   /*
 895    * Reset all his options.
 896    */
 897   BZERO(ho, sizeof(*ho));
 898
 899   /*
 900    * Process all his options.
 901    */
 902   next = inp;
 903   while (l) {
 904     orc = CONFACK;       /* Assume success */
 905     cip = p = next;      /* Remember begining of CI */
 906     if (l < 2 ||         /* Not enough data for CI header or */
 907         p[1] < 2 ||      /*  CI length too small or */
 908         p[1] > l) {      /*  CI length too big? */
 909       IPCPDEBUG(LOG_INFO, ("ipcp_reqci: bad CI length!\n"));
 910       orc = CONFREJ;     /* Reject bad CI */
 911       cilen = (u_short)l;/* Reject till end of packet */
 912       l = 0;             /* Don't loop again */
 913       goto endswitch;
 914     }
 915     GETCHAR(citype, p);  /* Parse CI type */
 916     GETCHAR(cilen, p);   /* Parse CI length */
 917     l -= cilen;          /* Adjust remaining length */
 918     next += cilen;       /* Step to next CI */
 919
 920     switch (citype) {      /* Check CI type */
 921 #ifdef OLD_CI_ADDRS /* Need to save space... */
 922       case CI_ADDRS:
 923         IPCPDEBUG(LOG_INFO, ("ipcp_reqci: received ADDRS\n"));
 924         if (!ao->neg_addr ||
 925             cilen != CILEN_ADDRS) {  /* Check CI length */
 926           orc = CONFREJ;    /* Reject CI */
 927           break;
 928         }
 929
 930         /*
 931          * If he has no address, or if we both have his address but
 932          * disagree about it, then NAK it with our idea.
 933          * In particular, if we don't know his address, but he does,
 934          * then accept it.
 935          */
 936         GETLONG(tl, p);    /* Parse source address (his) */
 937         ciaddr1 = htonl(tl);
 938         IPCPDEBUG(LOG_INFO, ("his addr %s\n", inet_ntoa(ciaddr1)));
 939         if (ciaddr1 != wo->hisaddr
 940             && (ciaddr1 == 0 || !wo->accept_remote)) {
 941           orc = CONFNAK;
 942           if (!reject_if_disagree) {
 943             DECPTR(sizeof(u32_t), p);
 944             tl = ntohl(wo->hisaddr);
 945             PUTLONG(tl, p);
 946           }
 947         } else if (ciaddr1 == 0 && wo->hisaddr == 0) {
 948           /*
 949            * If neither we nor he knows his address, reject the option.
 950            */
 951           orc = CONFREJ;
 952           wo->req_addr = 0;  /* don't NAK with 0.0.0.0 later */
 953           break;
 954         }
 955
 956         /*
 957          * If he doesn't know our address, or if we both have our address
 958          * but disagree about it, then NAK it with our idea.
 959          */
 960         GETLONG(tl, p);    /* Parse desination address (ours) */
 961         ciaddr2 = htonl(tl);
 962         IPCPDEBUG(LOG_INFO, ("our addr %s\n", inet_ntoa(ciaddr2)));
 963         if (ciaddr2 != wo->ouraddr) {
 964           if (ciaddr2 == 0 || !wo->accept_local) {
 965             orc = CONFNAK;
 966             if (!reject_if_disagree) {
 967               DECPTR(sizeof(u32_t), p);
 968               tl = ntohl(wo->ouraddr);
 969               PUTLONG(tl, p);
 970             }
 971           } else {
 972             go->ouraddr = ciaddr2;  /* accept peer's idea */
 973           }
 974         }
 975
 976         ho->neg_addr = 1;
 977         ho->old_addrs = 1;
 978         ho->hisaddr = ciaddr1;
 979         ho->ouraddr = ciaddr2;
 980         break;
 981 #endif
 982
 983       case CI_ADDR:
 984         if (!ao->neg_addr) {
 985           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Reject ADDR not allowed\n"));
 986           orc = CONFREJ;        /* Reject CI */
 987           break;
 988         } else if (cilen != CILEN_ADDR) {  /* Check CI length */
 989           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Reject ADDR bad len\n"));
 990           orc = CONFREJ;        /* Reject CI */
 991           break;
 992         }
 993
 994         /*
 995          * If he has no address, or if we both have his address but
 996          * disagree about it, then NAK it with our idea.
 997          * In particular, if we don't know his address, but he does,
 998          * then accept it.
 999          */
1000         GETLONG(tl, p);  /* Parse source address (his) */
1001         ciaddr1 = htonl(tl);
1002         if (ciaddr1 != wo->hisaddr
1003             && (ciaddr1 == 0 || !wo->accept_remote)) {
1004           orc = CONFNAK;
1005           if (!reject_if_disagree) {
1006             DECPTR(sizeof(u32_t), p);
1007             tl = ntohl(wo->hisaddr);
1008             PUTLONG(tl, p);
1009           }
1010           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Nak ADDR %s\n", inet_ntoa(ciaddr1)));
1011         } else if (ciaddr1 == 0 && wo->hisaddr == 0) {
1012           /*
1013            * Don't ACK an address of 0.0.0.0 - reject it instead.
1014            */
1015           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Reject ADDR %s\n", inet_ntoa(ciaddr1)));
1016           orc = CONFREJ;
1017           wo->req_addr = 0;  /* don't NAK with 0.0.0.0 later */
1018           break;
1019         }
1020
1021         ho->neg_addr = 1;
1022         ho->hisaddr = ciaddr1;
1023         IPCPDEBUG(LOG_INFO, ("ipcp_reqci: ADDR %s\n", inet_ntoa(ciaddr1)));
1024         break;
1025
1026       case CI_MS_DNS1:
1027       case CI_MS_DNS2:
1028         /* Microsoft primary or secondary DNS request */
1029         d = citype == CI_MS_DNS2;
1030
1031         /* If we do not have a DNS address then we cannot send it */
1032         if (ao->dnsaddr[d] == 0 ||
1033             cilen != CILEN_ADDR) {  /* Check CI length */
1034           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting DNS%d Request\n", d+1));
1035           orc = CONFREJ;        /* Reject CI */
1036           break;
1037         }
1038         GETLONG(tl, p);
1039         if (htonl(tl) != ao->dnsaddr[d]) {
1040           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Naking DNS%d Request %s\n",
1041                 d+1, inet_ntoa(tl)));
1042           DECPTR(sizeof(u32_t), p);
1043           tl = ntohl(ao->dnsaddr[d]);
1044           PUTLONG(tl, p);
1045           orc = CONFNAK;
1046         }
1047         IPCPDEBUG(LOG_INFO, ("ipcp_reqci: received DNS%d Request\n", d+1));
1048         break;
1049
1050       case CI_MS_WINS1:
1051       case CI_MS_WINS2:
1052         /* Microsoft primary or secondary WINS request */
1053         d = citype == CI_MS_WINS2;
1054         IPCPDEBUG(LOG_INFO, ("ipcp_reqci: received WINS%d Request\n", d+1));
1055
1056         /* If we do not have a DNS address then we cannot send it */
1057         if (ao->winsaddr[d] == 0 ||
1058           cilen != CILEN_ADDR) {  /* Check CI length */
1059           orc = CONFREJ;      /* Reject CI */
1060           break;
1061         }
1062         GETLONG(tl, p);
1063         if (htonl(tl) != ao->winsaddr[d]) {
1064           DECPTR(sizeof(u32_t), p);
1065           tl = ntohl(ao->winsaddr[d]);
1066           PUTLONG(tl, p);
1067           orc = CONFNAK;
1068         }
1069         break;
1070
1071       case CI_COMPRESSTYPE:
1072         if (!ao->neg_vj) {
1073           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting COMPRESSTYPE not allowed\n"));
1074           orc = CONFREJ;
1075           break;
1076         } else if (cilen != CILEN_VJ && cilen != CILEN_COMPRESS) {
1077           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting COMPRESSTYPE len=%d\n", cilen));
1078           orc = CONFREJ;
1079           break;
1080         }
1081         GETSHORT(cishort, p);
1082
1083         if (!(cishort == IPCP_VJ_COMP ||
1084             (cishort == IPCP_VJ_COMP_OLD && cilen == CILEN_COMPRESS))) {
1085           IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting COMPRESSTYPE %d\n", cishort));
1086           orc = CONFREJ;
1087           break;
1088         }
1089
1090         ho->neg_vj = 1;
1091         ho->vj_protocol = cishort;
1092         if (cilen == CILEN_VJ) {
1093           GETCHAR(maxslotindex, p);
1094           if (maxslotindex > ao->maxslotindex) {
1095             IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Naking VJ max slot %d\n", maxslotindex));
1096             orc = CONFNAK;
1097             if (!reject_if_disagree) {
1098               DECPTR(1, p);
1099               PUTCHAR(ao->maxslotindex, p);
1100             }
1101           }
1102           GETCHAR(cflag, p);
1103           if (cflag && !ao->cflag) {
1104             IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Naking VJ cflag %d\n", cflag));
1105             orc = CONFNAK;
1106             if (!reject_if_disagree) {
1107               DECPTR(1, p);
1108               PUTCHAR(wo->cflag, p);
1109             }
1110           }
1111           ho->maxslotindex = maxslotindex;
1112           ho->cflag = cflag;
1113         } else {
1114           ho->old_vj = 1;
1115           ho->maxslotindex = MAX_SLOTS - 1;
1116           ho->cflag = 1;
1117         }
1118         IPCPDEBUG(LOG_INFO, (
1119               "ipcp_reqci: received COMPRESSTYPE p=%d old=%d maxslot=%d cflag=%d\n",
1120               ho->vj_protocol, ho->old_vj, ho->maxslotindex, ho->cflag));
1121         break;
1122
1123       default:
1124         IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting unknown CI type %d\n", citype));
1125         orc = CONFREJ;
1126         break;
1127     }
1128
1129 endswitch:
1130     if (orc == CONFACK &&    /* Good CI */
1131         rc != CONFACK) {     /*  but prior CI wasnt? */
1132       continue;              /* Don't send this one */
1133     }
1134
1135     if (orc == CONFNAK) {    /* Nak this CI? */
1136       if (reject_if_disagree) {  /* Getting fed up with sending NAKs? */
1137         IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Rejecting too many naks\n"));
1138         orc = CONFREJ;       /* Get tough if so */
1139       } else {
1140         if (rc == CONFREJ) { /* Rejecting prior CI? */
1141           continue;          /* Don't send this one */
1142         }
1143         if (rc == CONFACK) { /* Ack'd all prior CIs? */
1144           rc = CONFNAK;      /* Not anymore... */
1145           ucp = inp;         /* Backup */
1146         }
1147       }
1148     }
1149
1150     if (orc == CONFREJ &&    /* Reject this CI */
1151         rc != CONFREJ) {  /*  but no prior ones? */
1152       rc = CONFREJ;
1153       ucp = inp;        /* Backup */
1154     }
1155
1156     /* Need to move CI? */
1157     if (ucp != cip) {
1158       BCOPY(cip, ucp, cilen);  /* Move it */
1159     }
1160
1161     /* Update output pointer */
1162     INCPTR(cilen, ucp);
1163   }
1164
1165   /*
1166    * If we aren't rejecting this packet, and we want to negotiate
1167    * their address, and they didn't send their address, then we
1168    * send a NAK with a CI_ADDR option appended.  We assume the
1169    * input buffer is long enough that we can append the extra
1170    * option safely.
1171    */
1172   if (rc != CONFREJ && !ho->neg_addr &&
1173       wo->req_addr && !reject_if_disagree) {
1174     IPCPDEBUG(LOG_INFO, ("ipcp_reqci: Requesting peer address\n"));
1175     if (rc == CONFACK) {
1176       rc = CONFNAK;
1177       ucp = inp;        /* reset pointer */
1178       wo->req_addr = 0;    /* don't ask again */
1179     }
1180     PUTCHAR(CI_ADDR, ucp);
1181     PUTCHAR(CILEN_ADDR, ucp);
1182     tl = ntohl(wo->hisaddr);
1183     PUTLONG(tl, ucp);
1184   }
1185
1186   *len = (int)(ucp - inp);    /* Compute output length */
1187   IPCPDEBUG(LOG_INFO, ("ipcp_reqci: returning Configure-%s\n", CODENAME(rc)));
1188   return (rc);      /* Return final code */
1189 }
1190
1191
1192 #if 0
1193 /*
1194  * ip_check_options - check that any IP-related options are OK,
1195  * and assign appropriate defaults.
1196  */
1197 static void
1198 ip_check_options(u_long localAddr)
1199 {
1200   ipcp_options *wo = &ipcp_wantoptions[0];
1201
1202   /*
1203    * Load our default IP address but allow the remote host to give us
1204    * a new address.
1205    */
1206   if (wo->ouraddr == 0 && !ppp_settings.disable_defaultip) {
1207     wo->accept_local = 1;  /* don't insist on this default value */
1208     wo->ouraddr = htonl(localAddr);
1209   }
1210 }
1211 #endif
1212
1213
1214 /*
1215  * ipcp_up - IPCP has come UP.
1216  *
1217  * Configure the IP network interface appropriately and bring it up.
1218  */
1219 static void
1220 ipcp_up(fsm *f)
1221 {
1222   u32_t mask;
1223   ipcp_options *ho = &ipcp_hisoptions[f->unit];
1224   ipcp_options *go = &ipcp_gotoptions[f->unit];
1225   ipcp_options *wo = &ipcp_wantoptions[f->unit];
1226
1227   np_up(f->unit, PPP_IP);
1228   IPCPDEBUG(LOG_INFO, ("ipcp: up\n"));
1229
1230   /*
1231    * We must have a non-zero IP address for both ends of the link.
1232    */
1233   if (!ho->neg_addr) {
1234     ho->hisaddr = wo->hisaddr;
1235   }
1236
1237   if (ho->hisaddr == 0) {
1238 #if 0
1239     IPCPDEBUG(LOG_ERR, ("Could not determine remote IP address\n"));
1240     ipcp_close(f->unit, "Could not determine remote IP address");
1241     return;
1242 #else //Kludge
1243     ho->hisaddr = 0; //Set remote IP to 0.0.0.0, this is needed as most 3g providers do not advertise the remote IP to the user
1244 #endif
1245   }
1246   if (go->ouraddr == 0) {
1247     IPCPDEBUG(LOG_ERR, ("Could not determine local IP address\n"));
1248     ipcp_close(f->unit, "Could not determine local IP address");
1249     return;
1250   }
1251
1252   if (ppp_settings.usepeerdns && (go->dnsaddr[0] || go->dnsaddr[1])) {
1253     /*pppGotDNSAddrs(go->dnsaddr[0], go->dnsaddr[1]);*/
1254   }
1255
1256   /*
1257    * Check that the peer is allowed to use the IP address it wants.
1258    */
1259   if (!auth_ip_addr(f->unit, ho->hisaddr)) {
1260     IPCPDEBUG(LOG_ERR, ("Peer is not authorized to use remote address %s\n",
1261         inet_ntoa(ho->hisaddr)));
1262     ipcp_close(f->unit, "Unauthorized remote IP address");
1263     return;
1264   }
1265
1266   /* set tcp compression */
1267   sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex);
1268
1269   /*
1270    * Set IP addresses and (if specified) netmask.
1271    */
1272   mask = GetMask(go->ouraddr);
1273
1274   if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask, go->dnsaddr[0], go->dnsaddr[1])) {
1275     IPCPDEBUG(LOG_WARNING, ("sifaddr failed\n"));
1276     ipcp_close(f->unit, "Interface configuration failed");
1277     return;
1278   }
1279
1280   /* bring the interface up for IP */
1281   if (!sifup(f->unit)) {
1282     IPCPDEBUG(LOG_WARNING, ("sifup failed\n"));
1283     ipcp_close(f->unit, "Interface configuration failed");
1284     return;
1285   }
1286
1287   sifnpmode(f->unit, PPP_IP, NPMODE_PASS);
1288
1289   /* assign a default route through the interface if required */
1290   if (ipcp_wantoptions[f->unit].default_route) {
1291     if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr)) {
1292       default_route_set[f->unit] = 1;
1293     }
1294   }
1295
1296   IPCPDEBUG(LOG_NOTICE, ("local  IP address %s\n", inet_ntoa(go->ouraddr)));
1297   IPCPDEBUG(LOG_NOTICE, ("remote IP address %s\n", inet_ntoa(ho->hisaddr)));
1298   if (go->dnsaddr[0]) {
1299     IPCPDEBUG(LOG_NOTICE, ("primary   DNS address %s\n", inet_ntoa(go->dnsaddr[0])));
1300   }
1301   if (go->dnsaddr[1]) {
1302     IPCPDEBUG(LOG_NOTICE, ("secondary DNS address %s\n", inet_ntoa(go->dnsaddr[1])));
1303   }
1304 }
1305
1306
1307 /*
1308  * ipcp_down - IPCP has gone DOWN.
1309  *
1310  * Take the IP network interface down, clear its addresses
1311  * and delete routes through it.
1312  */
1313 static void
1314 ipcp_down(fsm *f)
1315 {
1316   IPCPDEBUG(LOG_INFO, ("ipcp: down\n"));
1317   np_down(f->unit, PPP_IP);
1318   sifvjcomp(f->unit, 0, 0, 0);
1319
1320   sifdown(f->unit);
1321   ipcp_clear_addrs(f->unit);
1322 }
1323
1324
1325 /*
1326  * ipcp_clear_addrs() - clear the interface addresses, routes, etc.
1327  */
1328 static void
1329 ipcp_clear_addrs(int unit)
1330 {
1331   u32_t ouraddr, hisaddr;
1332
1333   ouraddr = ipcp_gotoptions[unit].ouraddr;
1334   hisaddr = ipcp_hisoptions[unit].hisaddr;
1335   if (default_route_set[unit]) {
1336     cifdefaultroute(unit, ouraddr, hisaddr);
1337     default_route_set[unit] = 0;
1338   }
1339   cifaddr(unit, ouraddr, hisaddr);
1340 }
1341
1342
1343 /*
1344  * ipcp_finished - possibly shut down the lower layers.
1345  */
1346 static void
1347 ipcp_finished(fsm *f)
1348 {
1349   np_finished(f->unit, PPP_IP);
1350 }
1351
1352 #if PPP_ADDITIONAL_CALLBACKS
1353 static int
1354 ipcp_printpkt(u_char *p, int plen, void (*printer) (void *, char *, ...), void *arg)
1355 {
1356   LWIP_UNUSED_ARG(p);
1357   LWIP_UNUSED_ARG(plen);
1358   LWIP_UNUSED_ARG(printer);
1359   LWIP_UNUSED_ARG(arg);
1360   return 0;
1361 }
1362
1363 /*
1364  * ip_active_pkt - see if this IP packet is worth bringing the link up for.
1365  * We don't bring the link up for IP fragments or for TCP FIN packets
1366  * with no data.
1367  */
1368 #define IP_HDRLEN   20  /* bytes */
1369 #define IP_OFFMASK  0x1fff
1370 #define IPPROTO_TCP 6
1371 #define TCP_HDRLEN  20
1372 #define TH_FIN      0x01
1373
1374 /*
1375  * We use these macros because the IP header may be at an odd address,
1376  * and some compilers might use word loads to get th_off or ip_hl.
1377  */
1378
1379 #define net_short(x)    (((x)[0] << 8) + (x)[1])
1380 #define get_iphl(x)     (((unsigned char *)(x))[0] & 0xF)
1381 #define get_ipoff(x)    net_short((unsigned char *)(x) + 6)
1382 #define get_ipproto(x)  (((unsigned char *)(x))[9])
1383 #define get_tcpoff(x)   (((unsigned char *)(x))[12] >> 4)
1384 #define get_tcpflags(x) (((unsigned char *)(x))[13])
1385
1386 static int
1387 ip_active_pkt(u_char *pkt, int len)
1388 {
1389   u_char *tcp;
1390   int hlen;
1391
1392   len -= PPP_HDRLEN;
1393   pkt += PPP_HDRLEN;
1394   if (len < IP_HDRLEN) {
1395     return 0;
1396   }
1397   if ((get_ipoff(pkt) & IP_OFFMASK) != 0) {
1398     return 0;
1399   }
1400   if (get_ipproto(pkt) != IPPROTO_TCP) {
1401     return 1;
1402   }
1403   hlen = get_iphl(pkt) * 4;
1404   if (len < hlen + TCP_HDRLEN) {
1405     return 0;
1406   }
1407   tcp = pkt + hlen;
1408   if ((get_tcpflags(tcp) & TH_FIN) != 0 && len == hlen + get_tcpoff(tcp) * 4) {
1409     return 0;
1410   }
1411   return 1;
1412 }
1413 #endif /* PPP_ADDITIONAL_CALLBACKS */
1414
1415 #endif /* PPP_SUPPORT */