1 /* $OpenBSD: ipcp.c,v 1.17 2024/08/10 05:32:28 jsg Exp $ */ 2 3 /* 4 * ipcp.c - PPP IP Control Protocol. 5 * 6 * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. The name "Carnegie Mellon University" must not be used to 21 * endorse or promote products derived from this software without 22 * prior written permission. For permission or any legal 23 * details, please contact 24 * Office of Technology Transfer 25 * Carnegie Mellon University 26 * 5000 Forbes Avenue 27 * Pittsburgh, PA 15213-3890 28 * (412) 268-4387, fax: (412) 268-7395 29 * tech-transfer@andrew.cmu.edu 30 * 31 * 4. Redistributions of any form whatsoever must retain the following 32 * acknowledgment: 33 * "This product includes software developed by Computing Services 34 * at Carnegie Mellon University (http://www.cmu.edu/computing/)." 35 * 36 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO 37 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 38 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE 39 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 40 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 41 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 42 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 43 */ 44 45 /* 46 * TODO: 47 */ 48 49 #include <sys/types.h> 50 #include <sys/socket.h> 51 #include <netinet/in.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <syslog.h> 56 #include <netdb.h> 57 58 #include "pppd.h" 59 #include "fsm.h" 60 #include "ipcp.h" 61 #include "pathnames.h" 62 63 /* global vars */ 64 ipcp_options ipcp_wantoptions[NUM_PPP]; /* Options that we want to request */ 65 ipcp_options ipcp_gotoptions[NUM_PPP]; /* Options that peer ack'd */ 66 ipcp_options ipcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */ 67 ipcp_options ipcp_hisoptions[NUM_PPP]; /* Options that we ack'd */ 68 69 /* local vars */ 70 static int cis_received[NUM_PPP]; /* # Conf-Reqs received */ 71 static int default_route_set[NUM_PPP]; /* Have set up a default route */ 72 static int proxy_arp_set[NUM_PPP]; /* Have created proxy arp entry */ 73 74 /* 75 * Callbacks for fsm code. (CI = Configuration Information) 76 */ 77 static void ipcp_resetci(fsm *); /* Reset our CI */ 78 static int ipcp_cilen(fsm *); /* Return length of our CI */ 79 static void ipcp_addci(fsm *, u_char *, int *); /* Add our CI */ 80 static int ipcp_ackci(fsm *, u_char *, int); /* Peer ack'd our CI */ 81 static int ipcp_nakci(fsm *, u_char *, int); /* Peer nak'd our CI */ 82 static int ipcp_rejci(fsm *, u_char *, int); /* Peer rej'd our CI */ 83 static int ipcp_reqci(fsm *, u_char *, int *, int); /* Rcv CI */ 84 static void ipcp_up(fsm *); /* We're UP */ 85 static void ipcp_down(fsm *); /* We're DOWN */ 86 static void ipcp_script(fsm *, char *); /* Run an up/down script */ 87 static void ipcp_finished(fsm *); /* Don't need lower layer */ 88 89 fsm ipcp_fsm[NUM_PPP]; /* IPCP fsm structure */ 90 91 static fsm_callbacks ipcp_callbacks = { /* IPCP callback routines */ 92 ipcp_resetci, /* Reset our Configuration Information */ 93 ipcp_cilen, /* Length of our Configuration Information */ 94 ipcp_addci, /* Add our Configuration Information */ 95 ipcp_ackci, /* ACK our Configuration Information */ 96 ipcp_nakci, /* NAK our Configuration Information */ 97 ipcp_rejci, /* Reject our Configuration Information */ 98 ipcp_reqci, /* Request peer's Configuration Information */ 99 ipcp_up, /* Called when fsm reaches OPENED state */ 100 ipcp_down, /* Called when fsm leaves OPENED state */ 101 NULL, /* Called when we want the lower layer up */ 102 ipcp_finished, /* Called when we want the lower layer down */ 103 NULL, /* Called when Protocol-Reject received */ 104 NULL, /* Retransmission is necessary */ 105 NULL, /* Called to handle protocol-specific codes */ 106 "IPCP" /* String name of protocol */ 107 }; 108 109 /* 110 * Protocol entry points from main code. 111 */ 112 static void ipcp_init(int); 113 static void ipcp_open(int); 114 static void ipcp_close(int, char *); 115 static void ipcp_lowerup(int); 116 static void ipcp_lowerdown(int); 117 static void ipcp_input(int, u_char *, int); 118 static void ipcp_protrej(int); 119 static int ipcp_printpkt(u_char *, int, void (*)(void *, char *, ...), void *); 120 static void ip_check_options(void); 121 static int ip_demand_conf(int); 122 static int ip_active_pkt(u_char *, int); 123 124 struct protent ipcp_protent = { 125 PPP_IPCP, 126 ipcp_init, 127 ipcp_input, 128 ipcp_protrej, 129 ipcp_lowerup, 130 ipcp_lowerdown, 131 ipcp_open, 132 ipcp_close, 133 ipcp_printpkt, 134 NULL, 135 1, 136 "IPCP", 137 ip_check_options, 138 ip_demand_conf, 139 ip_active_pkt 140 }; 141 142 static void ipcp_clear_addrs(int); 143 144 /* 145 * Lengths of configuration options. 146 */ 147 #define CILEN_VOID 2 148 #define CILEN_COMPRESS 4 /* min length for compression protocol opt. */ 149 #define CILEN_VJ 6 /* length for RFC1332 Van-Jacobson opt. */ 150 #define CILEN_ADDR 6 /* new-style single address option */ 151 #define CILEN_ADDRS 10 /* old-style dual address option */ 152 153 154 #define CODENAME(x) ((x) == CONFACK ? "ACK" : \ 155 (x) == CONFNAK ? "NAK" : "REJ") 156 157 158 /* 159 * Make a string representation of a network IP address. 160 */ 161 char * 162 ip_ntoa(u_int32_t ipaddr) 163 { 164 static char b[64]; 165 166 ipaddr = ntohl(ipaddr); 167 168 snprintf(b, sizeof b, "%d.%d.%d.%d", 169 (u_char)(ipaddr >> 24), 170 (u_char)(ipaddr >> 16), 171 (u_char)(ipaddr >> 8), 172 (u_char)(ipaddr)); 173 return b; 174 } 175 176 177 /* 178 * ipcp_init - Initialize IPCP. 179 */ 180 static void 181 ipcp_init(int unit) 182 { 183 fsm *f = &ipcp_fsm[unit]; 184 ipcp_options *wo = &ipcp_wantoptions[unit]; 185 ipcp_options *ao = &ipcp_allowoptions[unit]; 186 187 f->unit = unit; 188 f->protocol = PPP_IPCP; 189 f->callbacks = &ipcp_callbacks; 190 fsm_init(&ipcp_fsm[unit]); 191 192 memset(wo, 0, sizeof(*wo)); 193 memset(ao, 0, sizeof(*ao)); 194 195 wo->neg_addr = 1; 196 wo->neg_vj = 1; 197 wo->vj_protocol = IPCP_VJ_COMP; 198 wo->maxslotindex = MAX_STATES - 1; /* really max index */ 199 wo->cflag = 1; 200 201 /* max slots and slot-id compression are currently hardwired in */ 202 /* ppp_if.c to 16 and 1, this needs to be changed (among other */ 203 /* things) gmc */ 204 205 ao->neg_addr = 1; 206 ao->neg_vj = 1; 207 ao->maxslotindex = MAX_STATES - 1; 208 ao->cflag = 1; 209 210 /* 211 * XXX These control whether the user may use the proxyarp 212 * and defaultroute options. 213 */ 214 ao->proxy_arp = 1; 215 ao->default_route = 1; 216 } 217 218 219 /* 220 * ipcp_open - IPCP is allowed to come up. 221 */ 222 static void 223 ipcp_open(int unit) 224 { 225 fsm_open(&ipcp_fsm[unit]); 226 } 227 228 229 /* 230 * ipcp_close - Take IPCP down. 231 */ 232 static void 233 ipcp_close(int unit, char *reason) 234 { 235 fsm_close(&ipcp_fsm[unit], reason); 236 } 237 238 239 /* 240 * ipcp_lowerup - The lower layer is up. 241 */ 242 static void 243 ipcp_lowerup(int unit) 244 { 245 fsm_lowerup(&ipcp_fsm[unit]); 246 } 247 248 249 /* 250 * ipcp_lowerdown - The lower layer is down. 251 */ 252 static void 253 ipcp_lowerdown(int unit) 254 { 255 fsm_lowerdown(&ipcp_fsm[unit]); 256 } 257 258 259 /* 260 * ipcp_input - Input IPCP packet. 261 */ 262 static void 263 ipcp_input(int unit, u_char *p, int len) 264 { 265 fsm_input(&ipcp_fsm[unit], p, len); 266 } 267 268 269 /* 270 * ipcp_protrej - A Protocol-Reject was received for IPCP. 271 * 272 * Pretend the lower layer went down, so we shut up. 273 */ 274 static void 275 ipcp_protrej(int unit) 276 { 277 fsm_lowerdown(&ipcp_fsm[unit]); 278 } 279 280 281 /* 282 * ipcp_resetci - Reset our CI. 283 */ 284 static void 285 ipcp_resetci(fsm *f) 286 { 287 ipcp_options *wo = &ipcp_wantoptions[f->unit]; 288 289 wo->req_addr = wo->neg_addr && ipcp_allowoptions[f->unit].neg_addr; 290 if (wo->ouraddr == 0) 291 wo->accept_local = 1; 292 if (wo->hisaddr == 0) 293 wo->accept_remote = 1; 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) 311 312 /* 313 * First see if we want to change our options to the old 314 * forms because we have received old forms from the peer. 315 */ 316 if (wo->neg_addr && !go->neg_addr && !go->old_addrs) { 317 /* use the old style of address negotiation */ 318 go->neg_addr = 1; 319 go->old_addrs = 1; 320 } 321 if (wo->neg_vj && !go->neg_vj && !go->old_vj) { 322 /* try an older style of VJ negotiation */ 323 if (cis_received[f->unit] == 0) { 324 /* keep trying the new style until we see some CI from the peer */ 325 go->neg_vj = 1; 326 } else { 327 /* use the old style only if the peer did */ 328 if (ho->neg_vj && ho->old_vj) { 329 go->neg_vj = 1; 330 go->old_vj = 1; 331 go->vj_protocol = ho->vj_protocol; 332 } 333 } 334 } 335 336 return (LENCIADDR(go->neg_addr, go->old_addrs) + 337 LENCIVJ(go->neg_vj, go->old_vj)); 338 } 339 340 341 /* 342 * ipcp_addci - Add our desired CIs to a packet. 343 */ 344 static void 345 ipcp_addci(fsm *f, u_char *ucp, int *lenp) 346 { 347 ipcp_options *go = &ipcp_gotoptions[f->unit]; 348 int len = *lenp; 349 350 #define ADDCIVJ(opt, neg, val, old, maxslotindex, cflag) \ 351 if (neg) { \ 352 int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \ 353 if (len >= vjlen) { \ 354 PUTCHAR(opt, ucp); \ 355 PUTCHAR(vjlen, ucp); \ 356 PUTSHORT(val, ucp); \ 357 if (!old) { \ 358 PUTCHAR(maxslotindex, ucp); \ 359 PUTCHAR(cflag, ucp); \ 360 } \ 361 len -= vjlen; \ 362 } else \ 363 neg = 0; \ 364 } 365 366 #define ADDCIADDR(opt, neg, old, val1, val2) \ 367 if (neg) { \ 368 int addrlen = (old? CILEN_ADDRS: CILEN_ADDR); \ 369 if (len >= addrlen) { \ 370 u_int32_t l; \ 371 PUTCHAR(opt, ucp); \ 372 PUTCHAR(addrlen, ucp); \ 373 l = ntohl(val1); \ 374 PUTLONG(l, ucp); \ 375 if (old) { \ 376 l = ntohl(val2); \ 377 PUTLONG(l, ucp); \ 378 } \ 379 len -= addrlen; \ 380 } else \ 381 neg = 0; \ 382 } 383 384 ADDCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), go->neg_addr, 385 go->old_addrs, go->ouraddr, go->hisaddr); 386 387 ADDCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj, 388 go->maxslotindex, go->cflag); 389 390 *lenp -= len; 391 } 392 393 394 /* 395 * ipcp_ackci - Ack our CIs. 396 * 397 * Returns: 398 * 0 - Ack was bad. 399 * 1 - Ack was good. 400 */ 401 static int 402 ipcp_ackci(fsm *f, u_char *p, int len) 403 { 404 ipcp_options *go = &ipcp_gotoptions[f->unit]; 405 u_short cilen, citype, cishort; 406 u_int32_t cilong; 407 u_char cimaxslotindex, cicflag; 408 409 /* 410 * CIs must be in exactly the same order that we sent... 411 * Check packet length and CI length at each step. 412 * If we find any deviations, then this packet is bad. 413 */ 414 415 #define ACKCIVJ(opt, neg, val, old, maxslotindex, cflag) \ 416 if (neg) { \ 417 int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \ 418 if ((len -= vjlen) < 0) \ 419 goto bad; \ 420 GETCHAR(citype, p); \ 421 GETCHAR(cilen, p); \ 422 if (cilen != vjlen || \ 423 citype != opt) \ 424 goto bad; \ 425 GETSHORT(cishort, p); \ 426 if (cishort != val) \ 427 goto bad; \ 428 if (!old) { \ 429 GETCHAR(cimaxslotindex, p); \ 430 if (cimaxslotindex != maxslotindex) \ 431 goto bad; \ 432 GETCHAR(cicflag, p); \ 433 if (cicflag != cflag) \ 434 goto bad; \ 435 } \ 436 } 437 438 #define ACKCIADDR(opt, neg, old, val1, val2) \ 439 if (neg) { \ 440 int addrlen = (old? CILEN_ADDRS: CILEN_ADDR); \ 441 u_int32_t l; \ 442 if ((len -= addrlen) < 0) \ 443 goto bad; \ 444 GETCHAR(citype, p); \ 445 GETCHAR(cilen, p); \ 446 if (cilen != addrlen || \ 447 citype != opt) \ 448 goto bad; \ 449 GETLONG(l, p); \ 450 cilong = htonl(l); \ 451 if (val1 != cilong) \ 452 goto bad; \ 453 if (old) { \ 454 GETLONG(l, p); \ 455 cilong = htonl(l); \ 456 if (val2 != cilong) \ 457 goto bad; \ 458 } \ 459 } 460 461 ACKCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), go->neg_addr, 462 go->old_addrs, go->ouraddr, go->hisaddr); 463 464 ACKCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj, 465 go->maxslotindex, go->cflag); 466 467 /* 468 * If there are any remaining CIs, then this packet is bad. 469 */ 470 if (len != 0) 471 goto bad; 472 return (1); 473 474 bad: 475 IPCPDEBUG((LOG_INFO, "ipcp_ackci: received bad Ack!")); 476 return (0); 477 } 478 479 /* 480 * ipcp_nakci - Peer has sent a NAK for some of our CIs. 481 * This should not modify any state if the Nak is bad 482 * or if IPCP is in the OPENED state. 483 * 484 * Returns: 485 * 0 - Nak was bad. 486 * 1 - Nak was good. 487 */ 488 static int 489 ipcp_nakci(fsm *f, u_char *p, int len) 490 { 491 ipcp_options *go = &ipcp_gotoptions[f->unit]; 492 u_char cimaxslotindex, cicflag; 493 u_char citype, cilen, *next; 494 u_short cishort; 495 u_int32_t ciaddr1, ciaddr2, l; 496 ipcp_options no; /* options we've seen Naks for */ 497 ipcp_options try; /* options to request next time */ 498 499 BZERO(&no, sizeof(no)); 500 try = *go; 501 502 /* 503 * Any Nak'd CIs must be in exactly the same order that we sent. 504 * Check packet length and CI length at each step. 505 * If we find any deviations, then this packet is bad. 506 */ 507 #define NAKCIADDR(opt, neg, old, code) \ 508 if (go->neg && \ 509 len >= (cilen = (old? CILEN_ADDRS: CILEN_ADDR)) && \ 510 p[1] == cilen && \ 511 p[0] == opt) { \ 512 len -= cilen; \ 513 INCPTR(2, p); \ 514 GETLONG(l, p); \ 515 ciaddr1 = htonl(l); \ 516 if (old) { \ 517 GETLONG(l, p); \ 518 ciaddr2 = htonl(l); \ 519 no.old_addrs = 1; \ 520 } else \ 521 ciaddr2 = 0; \ 522 no.neg = 1; \ 523 code \ 524 } 525 526 #define NAKCIVJ(opt, neg, code) \ 527 if (go->neg && \ 528 ((cilen = p[1]) == CILEN_COMPRESS || cilen == CILEN_VJ) && \ 529 len >= cilen && \ 530 p[0] == opt) { \ 531 len -= cilen; \ 532 INCPTR(2, p); \ 533 GETSHORT(cishort, p); \ 534 no.neg = 1; \ 535 code \ 536 } 537 538 /* 539 * Accept the peer's idea of {our,his} address, if different 540 * from our idea, only if the accept_{local,remote} flag is set. 541 */ 542 NAKCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), neg_addr, go->old_addrs, 543 if (go->accept_local && ciaddr1) { /* Do we know our address? */ 544 try.ouraddr = ciaddr1; 545 IPCPDEBUG((LOG_INFO, "local IP address %s", 546 ip_ntoa(ciaddr1))); 547 } 548 if (go->accept_remote && ciaddr2) { /* Does he know his? */ 549 try.hisaddr = ciaddr2; 550 IPCPDEBUG((LOG_INFO, "remote IP address %s", 551 ip_ntoa(ciaddr2))); 552 } 553 ); 554 555 /* 556 * Accept the peer's value of maxslotindex provided that it 557 * is less than what we asked for. Turn off slot-ID compression 558 * if the peer wants. Send old-style compress-type option if 559 * the peer wants. 560 */ 561 NAKCIVJ(CI_COMPRESSTYPE, neg_vj, 562 if (cilen == CILEN_VJ) { 563 GETCHAR(cimaxslotindex, p); 564 GETCHAR(cicflag, p); 565 if (cishort == IPCP_VJ_COMP) { 566 try.old_vj = 0; 567 if (cimaxslotindex < go->maxslotindex) 568 try.maxslotindex = cimaxslotindex; 569 if (!cicflag) 570 try.cflag = 0; 571 } else { 572 try.neg_vj = 0; 573 } 574 } else { 575 if (cishort == IPCP_VJ_COMP || cishort == IPCP_VJ_COMP_OLD) { 576 try.old_vj = 1; 577 try.vj_protocol = cishort; 578 } else { 579 try.neg_vj = 0; 580 } 581 } 582 ); 583 584 /* 585 * There may be remaining CIs, if the peer is requesting negotiation 586 * on an option that we didn't include in our request packet. 587 * If they want to negotiate about IP addresses, we comply. 588 * If they want us to ask for compression, we refuse. 589 */ 590 while (len > CILEN_VOID) { 591 GETCHAR(citype, p); 592 GETCHAR(cilen, p); 593 if( (len -= cilen) < 0 ) 594 goto bad; 595 next = p + cilen - 2; 596 597 switch (citype) { 598 case CI_COMPRESSTYPE: 599 if (go->neg_vj || no.neg_vj || 600 (cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) 601 goto bad; 602 no.neg_vj = 1; 603 break; 604 case CI_ADDRS: 605 if ((go->neg_addr && go->old_addrs) || no.old_addrs 606 || cilen != CILEN_ADDRS) 607 goto bad; 608 try.neg_addr = 1; 609 try.old_addrs = 1; 610 GETLONG(l, p); 611 ciaddr1 = htonl(l); 612 if (ciaddr1 && go->accept_local) 613 try.ouraddr = ciaddr1; 614 GETLONG(l, p); 615 ciaddr2 = htonl(l); 616 if (ciaddr2 && go->accept_remote) 617 try.hisaddr = ciaddr2; 618 no.old_addrs = 1; 619 break; 620 case CI_ADDR: 621 if (go->neg_addr || no.neg_addr || cilen != CILEN_ADDR) 622 goto bad; 623 try.old_addrs = 0; 624 GETLONG(l, p); 625 ciaddr1 = htonl(l); 626 if (ciaddr1 && go->accept_local) 627 try.ouraddr = ciaddr1; 628 if (try.ouraddr != 0) 629 try.neg_addr = 1; 630 no.neg_addr = 1; 631 break; 632 } 633 p = next; 634 } 635 636 /* If there is still anything left, this packet is bad. */ 637 if (len != 0) 638 goto bad; 639 640 /* 641 * OK, the Nak is good. Now we can update state. 642 */ 643 if (f->state != OPENED) 644 *go = try; 645 646 return 1; 647 648 bad: 649 IPCPDEBUG((LOG_INFO, "ipcp_nakci: received bad Nak!")); 650 return 0; 651 } 652 653 654 /* 655 * ipcp_rejci - Reject some of our CIs. 656 */ 657 static int 658 ipcp_rejci(fsm *f, u_char *p, int len) 659 { 660 ipcp_options *go = &ipcp_gotoptions[f->unit]; 661 u_char cimaxslotindex, ciflag, cilen; 662 u_short cishort; 663 u_int32_t cilong; 664 ipcp_options try; /* options to request next time */ 665 666 try = *go; 667 /* 668 * Any Rejected CIs must be in exactly the same order that we sent. 669 * Check packet length and CI length at each step. 670 * If we find any deviations, then this packet is bad. 671 */ 672 #define REJCIADDR(opt, neg, old, val1, val2) \ 673 if (go->neg && \ 674 len >= (cilen = old? CILEN_ADDRS: CILEN_ADDR) && \ 675 p[1] == cilen && \ 676 p[0] == opt) { \ 677 u_int32_t l; \ 678 len -= cilen; \ 679 INCPTR(2, p); \ 680 GETLONG(l, p); \ 681 cilong = htonl(l); \ 682 /* Check rejected value. */ \ 683 if (cilong != val1) \ 684 goto bad; \ 685 if (old) { \ 686 GETLONG(l, p); \ 687 cilong = htonl(l); \ 688 /* Check rejected value. */ \ 689 if (cilong != val2) \ 690 goto bad; \ 691 } \ 692 try.neg = 0; \ 693 } 694 695 #define REJCIVJ(opt, neg, val, old, maxslot, cflag) \ 696 if (go->neg && \ 697 p[1] == (old? CILEN_COMPRESS : CILEN_VJ) && \ 698 len >= p[1] && \ 699 p[0] == opt) { \ 700 len -= p[1]; \ 701 INCPTR(2, p); \ 702 GETSHORT(cishort, p); \ 703 /* Check rejected value. */ \ 704 if (cishort != val) \ 705 goto bad; \ 706 if (!old) { \ 707 GETCHAR(cimaxslotindex, p); \ 708 if (cimaxslotindex != maxslot) \ 709 goto bad; \ 710 GETCHAR(ciflag, p); \ 711 if (ciflag != cflag) \ 712 goto bad; \ 713 } \ 714 try.neg = 0; \ 715 } 716 717 REJCIADDR((go->old_addrs? CI_ADDRS: CI_ADDR), neg_addr, 718 go->old_addrs, go->ouraddr, go->hisaddr); 719 720 REJCIVJ(CI_COMPRESSTYPE, neg_vj, go->vj_protocol, go->old_vj, 721 go->maxslotindex, go->cflag); 722 723 /* 724 * If there are any remaining CIs, then this packet is bad. 725 */ 726 if (len != 0) 727 goto bad; 728 /* 729 * Now we can update state. 730 */ 731 if (f->state != OPENED) 732 *go = try; 733 return 1; 734 735 bad: 736 IPCPDEBUG((LOG_INFO, "ipcp_rejci: received bad Reject!")); 737 return 0; 738 } 739 740 741 /* 742 * ipcp_reqci - Check the peer's requested CIs and send appropriate response. 743 * 744 * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified 745 * appropriately. If reject_if_disagree is non-zero, doesn't return 746 * CONFNAK; returns CONFREJ if it can't return CONFACK. 747 */ 748 static int 749 ipcp_reqci(fsm *f, u_char *inp, int *len, int reject_if_disagree) 750 { 751 ipcp_options *wo = &ipcp_wantoptions[f->unit]; 752 ipcp_options *ho = &ipcp_hisoptions[f->unit]; 753 ipcp_options *ao = &ipcp_allowoptions[f->unit]; 754 ipcp_options *go = &ipcp_gotoptions[f->unit]; 755 u_char *cip, *next; /* Pointer to current and next CIs */ 756 u_short cilen, citype; /* Parsed len, type */ 757 u_short cishort; /* Parsed short value */ 758 u_int32_t tl, ciaddr1, ciaddr2;/* Parsed address values */ 759 int rc = CONFACK; /* Final packet return code */ 760 int orc; /* Individual option return code */ 761 u_char *p; /* Pointer to next char to parse */ 762 u_char *ucp = inp; /* Pointer to current output char */ 763 int l = *len; /* Length left */ 764 u_char maxslotindex, cflag; 765 int d; 766 767 cis_received[f->unit] = 1; 768 769 /* 770 * Reset all his options. 771 */ 772 BZERO(ho, sizeof(*ho)); 773 774 /* 775 * Process all his options. 776 */ 777 next = inp; 778 while (l) { 779 orc = CONFACK; /* Assume success */ 780 cip = p = next; /* Remember beginning of CI */ 781 if (l < 2 || /* Not enough data for CI header or */ 782 p[1] < 2 || /* CI length too small or */ 783 p[1] > l) { /* CI length too big? */ 784 IPCPDEBUG((LOG_INFO, "ipcp_reqci: bad CI length!")); 785 orc = CONFREJ; /* Reject bad CI */ 786 cilen = l; /* Reject till end of packet */ 787 l = 0; /* Don't loop again */ 788 goto endswitch; 789 } 790 GETCHAR(citype, p); /* Parse CI type */ 791 GETCHAR(cilen, p); /* Parse CI length */ 792 l -= cilen; /* Adjust remaining length */ 793 next += cilen; /* Step to next CI */ 794 795 switch (citype) { /* Check CI type */ 796 case CI_ADDRS: 797 IPCPDEBUG((LOG_INFO, "ipcp: received ADDRS ")); 798 if (!ao->neg_addr || 799 cilen != CILEN_ADDRS) { /* Check CI length */ 800 orc = CONFREJ; /* Reject CI */ 801 break; 802 } 803 804 /* 805 * If he has no address, or if we both have his address but 806 * disagree about it, then NAK it with our idea. 807 * In particular, if we don't know his address, but he does, 808 * then accept it. 809 */ 810 GETLONG(tl, p); /* Parse source address (his) */ 811 ciaddr1 = htonl(tl); 812 IPCPDEBUG((LOG_INFO, "(%s:", ip_ntoa(ciaddr1))); 813 if (ciaddr1 != wo->hisaddr 814 && (ciaddr1 == 0 || !wo->accept_remote)) { 815 orc = CONFNAK; 816 if (!reject_if_disagree) { 817 DECPTR(sizeof(u_int32_t), p); 818 tl = ntohl(wo->hisaddr); 819 PUTLONG(tl, p); 820 } 821 } else if (ciaddr1 == 0 && wo->hisaddr == 0) { 822 /* 823 * If neither we nor he knows his address, reject the option. 824 */ 825 orc = CONFREJ; 826 wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */ 827 break; 828 } 829 830 /* 831 * If he doesn't know our address, or if we both have our address 832 * but disagree about it, then NAK it with our idea. 833 */ 834 GETLONG(tl, p); /* Parse destination address (ours) */ 835 ciaddr2 = htonl(tl); 836 IPCPDEBUG((LOG_INFO, "%s)", ip_ntoa(ciaddr2))); 837 if (ciaddr2 != wo->ouraddr) { 838 if (ciaddr2 == 0 || !wo->accept_local) { 839 orc = CONFNAK; 840 if (!reject_if_disagree) { 841 DECPTR(sizeof(u_int32_t), p); 842 tl = ntohl(wo->ouraddr); 843 PUTLONG(tl, p); 844 } 845 } else { 846 go->ouraddr = ciaddr2; /* accept peer's idea */ 847 } 848 } 849 850 ho->neg_addr = 1; 851 ho->old_addrs = 1; 852 ho->hisaddr = ciaddr1; 853 ho->ouraddr = ciaddr2; 854 break; 855 856 case CI_ADDR: 857 IPCPDEBUG((LOG_INFO, "ipcp: received ADDR ")); 858 859 if (!ao->neg_addr || 860 cilen != CILEN_ADDR) { /* Check CI length */ 861 orc = CONFREJ; /* Reject CI */ 862 break; 863 } 864 865 /* 866 * If he has no address, or if we both have his address but 867 * disagree about it, then NAK it with our idea. 868 * In particular, if we don't know his address, but he does, 869 * then accept it. 870 */ 871 GETLONG(tl, p); /* Parse source address (his) */ 872 ciaddr1 = htonl(tl); 873 IPCPDEBUG((LOG_INFO, "(%s)", ip_ntoa(ciaddr1))); 874 if (ciaddr1 != wo->hisaddr 875 && (ciaddr1 == 0 || !wo->accept_remote)) { 876 orc = CONFNAK; 877 if (!reject_if_disagree) { 878 DECPTR(sizeof(u_int32_t), p); 879 tl = ntohl(wo->hisaddr); 880 PUTLONG(tl, p); 881 } 882 } else if (ciaddr1 == 0 && wo->hisaddr == 0) { 883 /* 884 * Don't ACK an address of 0.0.0.0 - reject it instead. 885 */ 886 orc = CONFREJ; 887 wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */ 888 break; 889 } 890 891 ho->neg_addr = 1; 892 ho->hisaddr = ciaddr1; 893 break; 894 895 case CI_MS_DNS1: 896 case CI_MS_DNS2: 897 /* Microsoft primary or secondary DNS request */ 898 d = citype == CI_MS_DNS2; 899 IPCPDEBUG((LOG_INFO, "ipcp: received DNS%d Request ", d+1)); 900 901 /* If we do not have a DNS address then we cannot send it */ 902 if (ao->dnsaddr[d] == 0 || 903 cilen != CILEN_ADDR) { /* Check CI length */ 904 orc = CONFREJ; /* Reject CI */ 905 break; 906 } 907 GETLONG(tl, p); 908 if (htonl(tl) != ao->dnsaddr[d]) { 909 DECPTR(sizeof(u_int32_t), p); 910 tl = ntohl(ao->dnsaddr[d]); 911 PUTLONG(tl, p); 912 orc = CONFNAK; 913 } 914 break; 915 916 case CI_MS_WINS1: 917 case CI_MS_WINS2: 918 /* Microsoft primary or secondary WINS request */ 919 d = citype == CI_MS_WINS2; 920 IPCPDEBUG((LOG_INFO, "ipcp: received WINS%d Request ", d+1)); 921 922 /* If we do not have a DNS address then we cannot send it */ 923 if (ao->winsaddr[d] == 0 || 924 cilen != CILEN_ADDR) { /* Check CI length */ 925 orc = CONFREJ; /* Reject CI */ 926 break; 927 } 928 GETLONG(tl, p); 929 if (htonl(tl) != ao->winsaddr[d]) { 930 DECPTR(sizeof(u_int32_t), p); 931 tl = ntohl(ao->winsaddr[d]); 932 PUTLONG(tl, p); 933 orc = CONFNAK; 934 } 935 break; 936 937 case CI_COMPRESSTYPE: 938 IPCPDEBUG((LOG_INFO, "ipcp: received COMPRESSTYPE ")); 939 if (!ao->neg_vj || 940 (cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) { 941 orc = CONFREJ; 942 break; 943 } 944 GETSHORT(cishort, p); 945 IPCPDEBUG((LOG_INFO, "(%d)", cishort)); 946 947 if (!(cishort == IPCP_VJ_COMP || 948 (cishort == IPCP_VJ_COMP_OLD && cilen == CILEN_COMPRESS))) { 949 orc = CONFREJ; 950 break; 951 } 952 953 ho->neg_vj = 1; 954 ho->vj_protocol = cishort; 955 if (cilen == CILEN_VJ) { 956 GETCHAR(maxslotindex, p); 957 if (maxslotindex > ao->maxslotindex) { 958 orc = CONFNAK; 959 if (!reject_if_disagree){ 960 DECPTR(1, p); 961 PUTCHAR(ao->maxslotindex, p); 962 } 963 } 964 GETCHAR(cflag, p); 965 if (cflag && !ao->cflag) { 966 orc = CONFNAK; 967 if (!reject_if_disagree){ 968 DECPTR(1, p); 969 PUTCHAR(wo->cflag, p); 970 } 971 } 972 ho->maxslotindex = maxslotindex; 973 ho->cflag = cflag; 974 } else { 975 ho->old_vj = 1; 976 ho->maxslotindex = MAX_STATES - 1; 977 ho->cflag = 1; 978 } 979 break; 980 981 default: 982 orc = CONFREJ; 983 break; 984 } 985 986 endswitch: 987 IPCPDEBUG((LOG_INFO, " (%s)\n", CODENAME(orc))); 988 989 if (orc == CONFACK && /* Good CI */ 990 rc != CONFACK) /* but prior CI wasnt? */ 991 continue; /* Don't send this one */ 992 993 if (orc == CONFNAK) { /* Nak this CI? */ 994 if (reject_if_disagree) /* Getting fed up with sending NAKs? */ 995 orc = CONFREJ; /* Get tough if so */ 996 else { 997 if (rc == CONFREJ) /* Rejecting prior CI? */ 998 continue; /* Don't send this one */ 999 if (rc == CONFACK) { /* Ack'd all prior CIs? */ 1000 rc = CONFNAK; /* Not anymore... */ 1001 ucp = inp; /* Backup */ 1002 } 1003 } 1004 } 1005 1006 if (orc == CONFREJ && /* Reject this CI */ 1007 rc != CONFREJ) { /* but no prior ones? */ 1008 rc = CONFREJ; 1009 ucp = inp; /* Backup */ 1010 } 1011 1012 /* Need to move CI? */ 1013 if (ucp != cip) 1014 BCOPY(cip, ucp, cilen); /* Move it */ 1015 1016 /* Update output pointer */ 1017 INCPTR(cilen, ucp); 1018 } 1019 1020 /* 1021 * If we aren't rejecting this packet, and we want to negotiate 1022 * their address, and they didn't send their address, then we 1023 * send a NAK with a CI_ADDR option appended. We assume the 1024 * input buffer is long enough that we can append the extra 1025 * option safely. 1026 */ 1027 if (rc != CONFREJ && !ho->neg_addr && 1028 wo->req_addr && !reject_if_disagree) { 1029 if (rc == CONFACK) { 1030 rc = CONFNAK; 1031 ucp = inp; /* reset pointer */ 1032 wo->req_addr = 0; /* don't ask again */ 1033 } 1034 PUTCHAR(CI_ADDR, ucp); 1035 PUTCHAR(CILEN_ADDR, ucp); 1036 tl = ntohl(wo->hisaddr); 1037 PUTLONG(tl, ucp); 1038 } 1039 1040 *len = ucp - inp; /* Compute output length */ 1041 IPCPDEBUG((LOG_INFO, "ipcp: returning Configure-%s", CODENAME(rc))); 1042 return (rc); /* Return final code */ 1043 } 1044 1045 1046 /* 1047 * ip_check_options - check that any IP-related options are OK, 1048 * and assign appropriate defaults. 1049 */ 1050 static void 1051 ip_check_options(void) 1052 { 1053 struct hostent *hp; 1054 u_int32_t local; 1055 ipcp_options *wo = &ipcp_wantoptions[0]; 1056 1057 /* 1058 * Default our local IP address based on our hostname. 1059 * If local IP address already given, don't bother. 1060 */ 1061 if (wo->ouraddr == 0 && !disable_defaultip) { 1062 /* 1063 * Look up our hostname (possibly with domain name appended) 1064 * and take the first IP address as our local IP address. 1065 * If there isn't an IP address for our hostname, too bad. 1066 */ 1067 wo->accept_local = 1; /* don't insist on this default value */ 1068 if ((hp = gethostbyname(hostname)) != NULL) { 1069 local = *(u_int32_t *)hp->h_addr; 1070 if (local != 0 && !bad_ip_adrs(local)) 1071 wo->ouraddr = local; 1072 } 1073 } 1074 1075 if (demand && wo->hisaddr == 0) { 1076 option_error("remote IP address required for demand-dialling\n"); 1077 exit(1); 1078 } 1079 #if 0 1080 if (demand && wo->accept_remote) { 1081 option_error("ipcp-accept-remote is incompatible with demand\n"); 1082 exit(1); 1083 } 1084 #endif 1085 } 1086 1087 1088 /* 1089 * ip_demand_conf - configure the interface as though 1090 * IPCP were up, for use with dial-on-demand. 1091 */ 1092 static int 1093 ip_demand_conf(int u) 1094 { 1095 ipcp_options *wo = &ipcp_wantoptions[u]; 1096 1097 if (!sifaddr(u, wo->ouraddr, wo->hisaddr, GetMask(wo->ouraddr))) 1098 return 0; 1099 if (!sifup(u)) 1100 return 0; 1101 if (!sifnpmode(u, PPP_IP, NPMODE_QUEUE)) 1102 return 0; 1103 if (wo->default_route) 1104 if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr)) 1105 default_route_set[u] = 1; 1106 if (wo->proxy_arp) 1107 if (sifproxyarp(u, wo->hisaddr)) 1108 proxy_arp_set[u] = 1; 1109 1110 syslog(LOG_NOTICE, "local IP address %s", ip_ntoa(wo->ouraddr)); 1111 syslog(LOG_NOTICE, "remote IP address %s", ip_ntoa(wo->hisaddr)); 1112 1113 return 1; 1114 } 1115 1116 1117 /* 1118 * ipcp_up - IPCP has come UP. 1119 * 1120 * Configure the IP network interface appropriately and bring it up. 1121 */ 1122 static void 1123 ipcp_up(fsm *f) 1124 { 1125 u_int32_t mask; 1126 ipcp_options *ho = &ipcp_hisoptions[f->unit]; 1127 ipcp_options *go = &ipcp_gotoptions[f->unit]; 1128 ipcp_options *wo = &ipcp_wantoptions[f->unit]; 1129 1130 np_up(f->unit, PPP_IP); 1131 IPCPDEBUG((LOG_INFO, "ipcp: up")); 1132 1133 /* 1134 * We must have a non-zero IP address for both ends of the link. 1135 */ 1136 if (!ho->neg_addr) 1137 ho->hisaddr = wo->hisaddr; 1138 1139 if (ho->hisaddr == 0) { 1140 syslog(LOG_ERR, "Could not determine remote IP address"); 1141 ipcp_close(f->unit, "Could not determine remote IP address"); 1142 return; 1143 } 1144 if (go->ouraddr == 0) { 1145 syslog(LOG_ERR, "Could not determine local IP address"); 1146 ipcp_close(f->unit, "Could not determine local IP address"); 1147 return; 1148 } 1149 script_setenv("IPLOCAL", ip_ntoa(go->ouraddr)); 1150 script_setenv("IPREMOTE", ip_ntoa(ho->hisaddr)); 1151 1152 /* 1153 * Check that the peer is allowed to use the IP address it wants. 1154 */ 1155 if (!auth_ip_addr(f->unit, ho->hisaddr)) { 1156 syslog(LOG_ERR, "Peer is not authorized to use remote address %s", 1157 ip_ntoa(ho->hisaddr)); 1158 ipcp_close(f->unit, "Unauthorized remote IP address"); 1159 return; 1160 } 1161 1162 /* set tcp compression */ 1163 sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex); 1164 1165 /* 1166 * If we are doing dial-on-demand, the interface is already 1167 * configured, so we put out any saved-up packets, then set the 1168 * interface to pass IP packets. 1169 */ 1170 if (demand) { 1171 if (go->ouraddr != wo->ouraddr || ho->hisaddr != wo->hisaddr) { 1172 if (go->ouraddr != wo->ouraddr) 1173 syslog(LOG_WARNING, "Local IP address changed to %s", 1174 ip_ntoa(go->ouraddr)); 1175 if (ho->hisaddr != wo->hisaddr) 1176 syslog(LOG_WARNING, "Remote IP address changed to %s", 1177 ip_ntoa(ho->hisaddr)); 1178 ipcp_clear_addrs(f->unit); 1179 1180 /* Set the interface to the new addresses */ 1181 mask = GetMask(go->ouraddr); 1182 if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) { 1183 IPCPDEBUG((LOG_WARNING, "sifaddr failed")); 1184 ipcp_close(f->unit, "Interface configuration failed"); 1185 return; 1186 } 1187 1188 /* assign a default route through the interface if required */ 1189 if (ipcp_wantoptions[f->unit].default_route) 1190 if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr)) 1191 default_route_set[f->unit] = 1; 1192 1193 /* Make a proxy ARP entry if requested. */ 1194 if (ipcp_wantoptions[f->unit].proxy_arp) 1195 if (sifproxyarp(f->unit, ho->hisaddr)) 1196 proxy_arp_set[f->unit] = 1; 1197 1198 } 1199 demand_rexmit(PPP_IP); 1200 sifnpmode(f->unit, PPP_IP, NPMODE_PASS); 1201 1202 } else { 1203 /* 1204 * Set IP addresses and (if specified) netmask. 1205 */ 1206 mask = GetMask(go->ouraddr); 1207 1208 #if !(defined(SVR4) && (defined(SNI) || defined(__USLC__))) 1209 if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) { 1210 IPCPDEBUG((LOG_WARNING, "sifaddr failed")); 1211 ipcp_close(f->unit, "Interface configuration failed"); 1212 return; 1213 } 1214 #endif 1215 1216 /* bring the interface up for IP */ 1217 if (!sifup(f->unit)) { 1218 IPCPDEBUG((LOG_WARNING, "sifup failed")); 1219 ipcp_close(f->unit, "Interface configuration failed"); 1220 return; 1221 } 1222 1223 #if (defined(SVR4) && (defined(SNI) || defined(__USLC__))) 1224 if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) { 1225 IPCPDEBUG((LOG_WARNING, "sifaddr failed")); 1226 ipcp_close(f->unit, "Interface configuration failed"); 1227 return; 1228 } 1229 #endif 1230 sifnpmode(f->unit, PPP_IP, NPMODE_PASS); 1231 1232 /* assign a default route through the interface if required */ 1233 if (ipcp_wantoptions[f->unit].default_route) 1234 if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr)) 1235 default_route_set[f->unit] = 1; 1236 1237 /* Make a proxy ARP entry if requested. */ 1238 if (ipcp_wantoptions[f->unit].proxy_arp) 1239 if (sifproxyarp(f->unit, ho->hisaddr)) 1240 proxy_arp_set[f->unit] = 1; 1241 1242 syslog(LOG_NOTICE, "local IP address %s", ip_ntoa(go->ouraddr)); 1243 syslog(LOG_NOTICE, "remote IP address %s", ip_ntoa(ho->hisaddr)); 1244 } 1245 1246 /* 1247 * Execute the ip-up script, like this: 1248 * /etc/ppp/ip-up interface tty speed local-IP remote-IP 1249 */ 1250 ipcp_script(f, _PATH_IPUP); 1251 1252 } 1253 1254 1255 /* 1256 * ipcp_down - IPCP has gone DOWN. 1257 * 1258 * Take the IP network interface down, clear its addresses 1259 * and delete routes through it. 1260 */ 1261 static void 1262 ipcp_down(fsm *f) 1263 { 1264 IPCPDEBUG((LOG_INFO, "ipcp: down")); 1265 np_down(f->unit, PPP_IP); 1266 sifvjcomp(f->unit, 0, 0, 0); 1267 1268 /* 1269 * If we are doing dial-on-demand, set the interface 1270 * to queue up outgoing packets (for now). 1271 */ 1272 if (demand) { 1273 sifnpmode(f->unit, PPP_IP, NPMODE_QUEUE); 1274 } else { 1275 sifdown(f->unit); 1276 ipcp_clear_addrs(f->unit); 1277 } 1278 1279 /* Execute the ip-down script */ 1280 ipcp_script(f, _PATH_IPDOWN); 1281 } 1282 1283 1284 /* 1285 * ipcp_clear_addrs() - clear the interface addresses, routes, 1286 * proxy arp entries, etc. 1287 */ 1288 static void 1289 ipcp_clear_addrs(int unit) 1290 { 1291 u_int32_t ouraddr, hisaddr; 1292 1293 ouraddr = ipcp_gotoptions[unit].ouraddr; 1294 hisaddr = ipcp_hisoptions[unit].hisaddr; 1295 if (proxy_arp_set[unit]) { 1296 cifproxyarp(unit, hisaddr); 1297 proxy_arp_set[unit] = 0; 1298 } 1299 if (default_route_set[unit]) { 1300 cifdefaultroute(unit, ouraddr, hisaddr); 1301 default_route_set[unit] = 0; 1302 } 1303 cifaddr(unit, ouraddr, hisaddr); 1304 } 1305 1306 1307 /* 1308 * ipcp_finished - possibly shut down the lower layers. 1309 */ 1310 static void 1311 ipcp_finished(fsm *f) 1312 { 1313 np_finished(f->unit, PPP_IP); 1314 } 1315 1316 1317 /* 1318 * ipcp_script - Execute a script with arguments 1319 * interface-name tty-name speed local-IP remote-IP. 1320 */ 1321 static void 1322 ipcp_script(fsm *f, char *script) 1323 { 1324 char strspeed[32], strlocal[32], strremote[32]; 1325 char *argv[8]; 1326 1327 snprintf(strspeed, sizeof strspeed, "%d", baud_rate); 1328 strlcpy(strlocal, ip_ntoa(ipcp_gotoptions[f->unit].ouraddr), 1329 sizeof strlocal); 1330 strlcpy(strremote, ip_ntoa(ipcp_hisoptions[f->unit].hisaddr), 1331 sizeof strremote); 1332 1333 argv[0] = script; 1334 argv[1] = ifname; 1335 argv[2] = devnam; 1336 argv[3] = strspeed; 1337 argv[4] = strlocal; 1338 argv[5] = strremote; 1339 argv[6] = ipparam; 1340 argv[7] = NULL; 1341 run_program(script, argv, 0); 1342 } 1343 1344 /* 1345 * ipcp_printpkt - print the contents of an IPCP packet. 1346 */ 1347 static char *ipcp_codenames[] = { 1348 "ConfReq", "ConfAck", "ConfNak", "ConfRej", 1349 "TermReq", "TermAck", "CodeRej" 1350 }; 1351 1352 static int 1353 ipcp_printpkt(u_char *p, int plen, void (*printer)(void *, char *, ...), void *arg) 1354 { 1355 int code, id, len, olen; 1356 u_char *pstart, *optend; 1357 u_short cishort; 1358 u_int32_t cilong; 1359 1360 if (plen < HEADERLEN) 1361 return 0; 1362 pstart = p; 1363 GETCHAR(code, p); 1364 GETCHAR(id, p); 1365 GETSHORT(len, p); 1366 if (len < HEADERLEN || len > plen) 1367 return 0; 1368 1369 if (code >= 1 && code <= sizeof(ipcp_codenames) / sizeof(char *)) 1370 printer(arg, " %s", ipcp_codenames[code-1]); 1371 else 1372 printer(arg, " code=0x%x", code); 1373 printer(arg, " id=0x%x", id); 1374 len -= HEADERLEN; 1375 switch (code) { 1376 case CONFREQ: 1377 case CONFACK: 1378 case CONFNAK: 1379 case CONFREJ: 1380 /* print option list */ 1381 while (len >= 2) { 1382 GETCHAR(code, p); 1383 GETCHAR(olen, p); 1384 p -= 2; 1385 if (olen < 2 || olen > len) { 1386 break; 1387 } 1388 printer(arg, " <"); 1389 len -= olen; 1390 optend = p + olen; 1391 switch (code) { 1392 case CI_ADDRS: 1393 if (olen == CILEN_ADDRS) { 1394 p += 2; 1395 GETLONG(cilong, p); 1396 printer(arg, "addrs %I", htonl(cilong)); 1397 GETLONG(cilong, p); 1398 printer(arg, " %I", htonl(cilong)); 1399 } 1400 break; 1401 case CI_COMPRESSTYPE: 1402 if (olen >= CILEN_COMPRESS) { 1403 p += 2; 1404 GETSHORT(cishort, p); 1405 printer(arg, "compress "); 1406 switch (cishort) { 1407 case IPCP_VJ_COMP: 1408 printer(arg, "VJ"); 1409 break; 1410 case IPCP_VJ_COMP_OLD: 1411 printer(arg, "old-VJ"); 1412 break; 1413 default: 1414 printer(arg, "0x%x", cishort); 1415 } 1416 } 1417 break; 1418 case CI_ADDR: 1419 if (olen == CILEN_ADDR) { 1420 p += 2; 1421 GETLONG(cilong, p); 1422 printer(arg, "addr %I", htonl(cilong)); 1423 } 1424 break; 1425 case CI_MS_DNS1: 1426 case CI_MS_DNS2: 1427 p += 2; 1428 GETLONG(cilong, p); 1429 printer(arg, "ms-dns %I", htonl(cilong)); 1430 break; 1431 case CI_MS_WINS1: 1432 case CI_MS_WINS2: 1433 p += 2; 1434 GETLONG(cilong, p); 1435 printer(arg, "ms-wins %I", htonl(cilong)); 1436 break; 1437 } 1438 while (p < optend) { 1439 GETCHAR(code, p); 1440 printer(arg, " %.2x", code); 1441 } 1442 printer(arg, ">"); 1443 } 1444 break; 1445 1446 case TERMACK: 1447 case TERMREQ: 1448 if (len > 0 && *p >= ' ' && *p < 0x7f) { 1449 printer(arg, " "); 1450 print_string(p, len, printer, arg); 1451 p += len; 1452 len = 0; 1453 } 1454 break; 1455 } 1456 1457 /* print the rest of the bytes in the packet */ 1458 for (; len > 0; --len) { 1459 GETCHAR(code, p); 1460 printer(arg, " %.2x", code); 1461 } 1462 1463 return p - pstart; 1464 } 1465 1466 /* 1467 * ip_active_pkt - see if this IP packet is worth bringing the link up for. 1468 * We don't bring the link up for IP fragments or for TCP FIN packets 1469 * with no data. 1470 */ 1471 #define IP_HDRLEN 20 /* bytes */ 1472 #define IP_OFFMASK 0x1fff 1473 #define IPPROTO_TCP 6 1474 #define TCP_HDRLEN 20 1475 #define TH_FIN 0x01 1476 1477 /* 1478 * We use these macros because the IP header may be at an odd address, 1479 * and some compilers might use word loads to get th_off or ip_hl. 1480 */ 1481 1482 #define net_short(x) (((x)[0] << 8) + (x)[1]) 1483 #define get_iphl(x) (((unsigned char *)(x))[0] & 0xF) 1484 #define get_ipoff(x) net_short((unsigned char *)(x) + 6) 1485 #define get_ipproto(x) (((unsigned char *)(x))[9]) 1486 #define get_tcpoff(x) (((unsigned char *)(x))[12] >> 4) 1487 #define get_tcpflags(x) (((unsigned char *)(x))[13]) 1488 1489 static int 1490 ip_active_pkt(u_char *pkt, int len) 1491 { 1492 u_char *tcp; 1493 int hlen; 1494 1495 len -= PPP_HDRLEN; 1496 pkt += PPP_HDRLEN; 1497 if (len < IP_HDRLEN) 1498 return 0; 1499 if ((get_ipoff(pkt) & IP_OFFMASK) != 0) 1500 return 0; 1501 if (get_ipproto(pkt) != IPPROTO_TCP) 1502 return 1; 1503 hlen = get_iphl(pkt) * 4; 1504 if (len < hlen + TCP_HDRLEN) 1505 return 0; 1506 tcp = pkt + hlen; 1507 if ((get_tcpflags(tcp) & TH_FIN) != 0 && len == hlen + get_tcpoff(tcp) * 4) 1508 return 0; 1509 return 1; 1510 } 1511