Travis Geiselbrecht | 1d0df69 | 2008-09-01 02:26:09 -0700 | [diff] [blame^] | 1 | /***************************************************************************** |
| 2 | * fsm.c - Network Control Protocol Finite State Machine program file. |
| 3 | * |
| 4 | * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc. |
| 5 | * portions Copyright (c) 1997 by Global Election Systems Inc. |
| 6 | * |
| 7 | * The authors hereby grant permission to use, copy, modify, distribute, |
| 8 | * and license this software and its documentation for any purpose, provided |
| 9 | * that existing copyright notices are retained in all copies and that this |
| 10 | * notice and the following disclaimer are included verbatim in any |
| 11 | * distributions. No written agreement, license, or royalty fee is required |
| 12 | * for any of the authorized uses. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR |
| 15 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 16 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 17 | * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 18 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 19 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 20 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 21 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 23 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 24 | * |
| 25 | ****************************************************************************** |
| 26 | * REVISION HISTORY |
| 27 | * |
| 28 | * 03-01-01 Marc Boucher <marc@mbsi.ca> |
| 29 | * Ported to lwIP. |
| 30 | * 97-12-01 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc. |
| 31 | * Original based on BSD fsm.c. |
| 32 | *****************************************************************************/ |
| 33 | /* |
| 34 | * fsm.c - {Link, IP} Control Protocol Finite State Machine. |
| 35 | * |
| 36 | * Copyright (c) 1989 Carnegie Mellon University. |
| 37 | * All rights reserved. |
| 38 | * |
| 39 | * Redistribution and use in source and binary forms are permitted |
| 40 | * provided that the above copyright notice and this paragraph are |
| 41 | * duplicated in all such forms and that any documentation, |
| 42 | * advertising materials, and other materials related to such |
| 43 | * distribution and use acknowledge that the software was developed |
| 44 | * by Carnegie Mellon University. The name of the |
| 45 | * University may not be used to endorse or promote products derived |
| 46 | * from this software without specific prior written permission. |
| 47 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
| 48 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
| 49 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 50 | */ |
| 51 | |
| 52 | |
| 53 | /* |
| 54 | * TODO: |
| 55 | * Randomize fsm id on link/init. |
| 56 | * Deal with variable outgoing MTU. |
| 57 | */ |
| 58 | |
| 59 | #include "ppp.h" |
| 60 | #if PPP_SUPPORT > 0 |
| 61 | #include "fsm.h" |
| 62 | #include "pppdebug.h" |
| 63 | |
| 64 | |
| 65 | /*************************/ |
| 66 | /*** LOCAL DEFINITIONS ***/ |
| 67 | /*************************/ |
| 68 | |
| 69 | |
| 70 | /************************/ |
| 71 | /*** LOCAL DATA TYPES ***/ |
| 72 | /************************/ |
| 73 | |
| 74 | |
| 75 | /***********************************/ |
| 76 | /*** LOCAL FUNCTION DECLARATIONS ***/ |
| 77 | /***********************************/ |
| 78 | static void fsm_timeout (void *); |
| 79 | static void fsm_rconfreq (fsm *, u_char, u_char *, int); |
| 80 | static void fsm_rconfack (fsm *, int, u_char *, int); |
| 81 | static void fsm_rconfnakrej (fsm *, int, int, u_char *, int); |
| 82 | static void fsm_rtermreq (fsm *, int, u_char *, int); |
| 83 | static void fsm_rtermack (fsm *); |
| 84 | static void fsm_rcoderej (fsm *, u_char *, int); |
| 85 | static void fsm_sconfreq (fsm *, int); |
| 86 | |
| 87 | #define PROTO_NAME(f) ((f)->callbacks->proto_name) |
| 88 | |
| 89 | |
| 90 | /******************************/ |
| 91 | /*** PUBLIC DATA STRUCTURES ***/ |
| 92 | /******************************/ |
| 93 | |
| 94 | |
| 95 | /*****************************/ |
| 96 | /*** LOCAL DATA STRUCTURES ***/ |
| 97 | /*****************************/ |
| 98 | int peer_mru[NUM_PPP]; |
| 99 | |
| 100 | |
| 101 | /***********************************/ |
| 102 | /*** PUBLIC FUNCTION DEFINITIONS ***/ |
| 103 | /***********************************/ |
| 104 | |
| 105 | /* |
| 106 | * fsm_init - Initialize fsm. |
| 107 | * |
| 108 | * Initialize fsm state. |
| 109 | */ |
| 110 | void fsm_init(fsm *f) |
| 111 | { |
| 112 | f->state = INITIAL; |
| 113 | f->flags = 0; |
| 114 | f->id = 0; /* XXX Start with random id? */ |
| 115 | f->timeouttime = FSM_DEFTIMEOUT; |
| 116 | f->maxconfreqtransmits = FSM_DEFMAXCONFREQS; |
| 117 | f->maxtermtransmits = FSM_DEFMAXTERMREQS; |
| 118 | f->maxnakloops = FSM_DEFMAXNAKLOOPS; |
| 119 | f->term_reason_len = 0; |
| 120 | } |
| 121 | |
| 122 | |
| 123 | /* |
| 124 | * fsm_lowerup - The lower layer is up. |
| 125 | */ |
| 126 | void fsm_lowerup(fsm *f) |
| 127 | { |
| 128 | int oldState = f->state; |
| 129 | |
| 130 | switch( f->state ){ |
| 131 | case INITIAL: |
| 132 | f->state = CLOSED; |
| 133 | break; |
| 134 | |
| 135 | case STARTING: |
| 136 | if( f->flags & OPT_SILENT ) |
| 137 | f->state = STOPPED; |
| 138 | else { |
| 139 | /* Send an initial configure-request */ |
| 140 | fsm_sconfreq(f, 0); |
| 141 | f->state = REQSENT; |
| 142 | } |
| 143 | break; |
| 144 | |
| 145 | default: |
| 146 | FSMDEBUG((LOG_INFO, "%s: Up event in state %d!\n", |
| 147 | PROTO_NAME(f), f->state)); |
| 148 | } |
| 149 | |
| 150 | FSMDEBUG((LOG_INFO, "%s: lowerup state %d -> %d\n", |
| 151 | PROTO_NAME(f), oldState, f->state)); |
| 152 | } |
| 153 | |
| 154 | |
| 155 | /* |
| 156 | * fsm_lowerdown - The lower layer is down. |
| 157 | * |
| 158 | * Cancel all timeouts and inform upper layers. |
| 159 | */ |
| 160 | void fsm_lowerdown(fsm *f) |
| 161 | { |
| 162 | int oldState = f->state; |
| 163 | |
| 164 | switch( f->state ){ |
| 165 | case CLOSED: |
| 166 | f->state = INITIAL; |
| 167 | break; |
| 168 | |
| 169 | case STOPPED: |
| 170 | f->state = STARTING; |
| 171 | if( f->callbacks->starting ) |
| 172 | (*f->callbacks->starting)(f); |
| 173 | break; |
| 174 | |
| 175 | case CLOSING: |
| 176 | f->state = INITIAL; |
| 177 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 178 | break; |
| 179 | |
| 180 | case STOPPING: |
| 181 | case REQSENT: |
| 182 | case ACKRCVD: |
| 183 | case ACKSENT: |
| 184 | f->state = STARTING; |
| 185 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 186 | break; |
| 187 | |
| 188 | case OPENED: |
| 189 | if( f->callbacks->down ) |
| 190 | (*f->callbacks->down)(f); |
| 191 | f->state = STARTING; |
| 192 | break; |
| 193 | |
| 194 | default: |
| 195 | FSMDEBUG((LOG_INFO, "%s: Down event in state %d!\n", |
| 196 | PROTO_NAME(f), f->state)); |
| 197 | } |
| 198 | |
| 199 | FSMDEBUG((LOG_INFO, "%s: lowerdown state %d -> %d\n", |
| 200 | PROTO_NAME(f), oldState, f->state)); |
| 201 | } |
| 202 | |
| 203 | |
| 204 | /* |
| 205 | * fsm_open - Link is allowed to come up. |
| 206 | */ |
| 207 | void fsm_open(fsm *f) |
| 208 | { |
| 209 | int oldState = f->state; |
| 210 | |
| 211 | switch( f->state ){ |
| 212 | case INITIAL: |
| 213 | f->state = STARTING; |
| 214 | if( f->callbacks->starting ) |
| 215 | (*f->callbacks->starting)(f); |
| 216 | break; |
| 217 | |
| 218 | case CLOSED: |
| 219 | if( f->flags & OPT_SILENT ) |
| 220 | f->state = STOPPED; |
| 221 | else { |
| 222 | /* Send an initial configure-request */ |
| 223 | fsm_sconfreq(f, 0); |
| 224 | f->state = REQSENT; |
| 225 | } |
| 226 | break; |
| 227 | |
| 228 | case CLOSING: |
| 229 | f->state = STOPPING; |
| 230 | /* fall through */ |
| 231 | case STOPPED: |
| 232 | case OPENED: |
| 233 | if( f->flags & OPT_RESTART ){ |
| 234 | fsm_lowerdown(f); |
| 235 | fsm_lowerup(f); |
| 236 | } |
| 237 | break; |
| 238 | } |
| 239 | |
| 240 | FSMDEBUG((LOG_INFO, "%s: open state %d -> %d\n", |
| 241 | PROTO_NAME(f), oldState, f->state)); |
| 242 | } |
| 243 | |
| 244 | |
| 245 | /* |
| 246 | * fsm_close - Start closing connection. |
| 247 | * |
| 248 | * Cancel timeouts and either initiate close or possibly go directly to |
| 249 | * the CLOSED state. |
| 250 | */ |
| 251 | void fsm_close(fsm *f, char *reason) |
| 252 | { |
| 253 | int oldState = f->state; |
| 254 | |
| 255 | f->term_reason = reason; |
| 256 | f->term_reason_len = (reason == NULL? 0: strlen(reason)); |
| 257 | switch( f->state ){ |
| 258 | case STARTING: |
| 259 | f->state = INITIAL; |
| 260 | break; |
| 261 | case STOPPED: |
| 262 | f->state = CLOSED; |
| 263 | break; |
| 264 | case STOPPING: |
| 265 | f->state = CLOSING; |
| 266 | break; |
| 267 | |
| 268 | case REQSENT: |
| 269 | case ACKRCVD: |
| 270 | case ACKSENT: |
| 271 | case OPENED: |
| 272 | if( f->state != OPENED ) |
| 273 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 274 | else if( f->callbacks->down ) |
| 275 | (*f->callbacks->down)(f); /* Inform upper layers we're down */ |
| 276 | |
| 277 | /* Init restart counter, send Terminate-Request */ |
| 278 | f->retransmits = f->maxtermtransmits; |
| 279 | fsm_sdata(f, TERMREQ, f->reqid = ++f->id, |
| 280 | (u_char *) f->term_reason, f->term_reason_len); |
| 281 | TIMEOUT(fsm_timeout, f, f->timeouttime); |
| 282 | --f->retransmits; |
| 283 | |
| 284 | f->state = CLOSING; |
| 285 | break; |
| 286 | } |
| 287 | |
| 288 | FSMDEBUG((LOG_INFO, "%s: close reason=%s state %d -> %d\n", |
| 289 | PROTO_NAME(f), reason, oldState, f->state)); |
| 290 | } |
| 291 | |
| 292 | |
| 293 | /* |
| 294 | * fsm_sdata - Send some data. |
| 295 | * |
| 296 | * Used for all packets sent to our peer by this module. |
| 297 | */ |
| 298 | void fsm_sdata( |
| 299 | fsm *f, |
| 300 | u_char code, |
| 301 | u_char id, |
| 302 | u_char *data, |
| 303 | int datalen |
| 304 | ) |
| 305 | { |
| 306 | u_char *outp; |
| 307 | int outlen; |
| 308 | |
| 309 | /* Adjust length to be smaller than MTU */ |
| 310 | outp = outpacket_buf[f->unit]; |
| 311 | if (datalen > peer_mru[f->unit] - (int)HEADERLEN) |
| 312 | datalen = peer_mru[f->unit] - HEADERLEN; |
| 313 | if (datalen && data != outp + PPP_HDRLEN + HEADERLEN) |
| 314 | BCOPY(data, outp + PPP_HDRLEN + HEADERLEN, datalen); |
| 315 | outlen = datalen + HEADERLEN; |
| 316 | MAKEHEADER(outp, f->protocol); |
| 317 | PUTCHAR(code, outp); |
| 318 | PUTCHAR(id, outp); |
| 319 | PUTSHORT(outlen, outp); |
| 320 | pppWrite(f->unit, outpacket_buf[f->unit], outlen + PPP_HDRLEN); |
| 321 | FSMDEBUG((LOG_INFO, "fsm_sdata(%s): Sent code %d,%d,%d.\n", |
| 322 | PROTO_NAME(f), code, id, outlen)); |
| 323 | } |
| 324 | |
| 325 | |
| 326 | /* |
| 327 | * fsm_input - Input packet. |
| 328 | */ |
| 329 | void fsm_input(fsm *f, u_char *inpacket, int l) |
| 330 | { |
| 331 | u_char *inp = inpacket; |
| 332 | u_char code, id; |
| 333 | int len; |
| 334 | |
| 335 | /* |
| 336 | * Parse header (code, id and length). |
| 337 | * If packet too short, drop it. |
| 338 | */ |
| 339 | if (l < HEADERLEN) { |
| 340 | FSMDEBUG((LOG_WARNING, "fsm_input(%x): Rcvd short header.\n", |
| 341 | f->protocol)); |
| 342 | return; |
| 343 | } |
| 344 | GETCHAR(code, inp); |
| 345 | GETCHAR(id, inp); |
| 346 | GETSHORT(len, inp); |
| 347 | if (len < HEADERLEN) { |
| 348 | FSMDEBUG((LOG_INFO, "fsm_input(%x): Rcvd illegal length.\n", |
| 349 | f->protocol)); |
| 350 | return; |
| 351 | } |
| 352 | if (len > l) { |
| 353 | FSMDEBUG((LOG_INFO, "fsm_input(%x): Rcvd short packet.\n", |
| 354 | f->protocol)); |
| 355 | return; |
| 356 | } |
| 357 | len -= HEADERLEN; /* subtract header length */ |
| 358 | |
| 359 | if( f->state == INITIAL || f->state == STARTING ){ |
| 360 | FSMDEBUG((LOG_INFO, "fsm_input(%x): Rcvd packet in state %d.\n", |
| 361 | f->protocol, f->state)); |
| 362 | return; |
| 363 | } |
| 364 | FSMDEBUG((LOG_INFO, "fsm_input(%s):%d,%d,%d\n", PROTO_NAME(f), code, id, l)); |
| 365 | /* |
| 366 | * Action depends on code. |
| 367 | */ |
| 368 | switch (code) { |
| 369 | case CONFREQ: |
| 370 | fsm_rconfreq(f, id, inp, len); |
| 371 | break; |
| 372 | |
| 373 | case CONFACK: |
| 374 | fsm_rconfack(f, id, inp, len); |
| 375 | break; |
| 376 | |
| 377 | case CONFNAK: |
| 378 | case CONFREJ: |
| 379 | fsm_rconfnakrej(f, code, id, inp, len); |
| 380 | break; |
| 381 | |
| 382 | case TERMREQ: |
| 383 | fsm_rtermreq(f, id, inp, len); |
| 384 | break; |
| 385 | |
| 386 | case TERMACK: |
| 387 | fsm_rtermack(f); |
| 388 | break; |
| 389 | |
| 390 | case CODEREJ: |
| 391 | fsm_rcoderej(f, inp, len); |
| 392 | break; |
| 393 | |
| 394 | default: |
| 395 | if( !f->callbacks->extcode |
| 396 | || !(*f->callbacks->extcode)(f, code, id, inp, len) ) |
| 397 | fsm_sdata(f, CODEREJ, ++f->id, inpacket, len + HEADERLEN); |
| 398 | break; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | |
| 403 | /* |
| 404 | * fsm_protreject - Peer doesn't speak this protocol. |
| 405 | * |
| 406 | * Treat this as a catastrophic error (RXJ-). |
| 407 | */ |
| 408 | void fsm_protreject(fsm *f) |
| 409 | { |
| 410 | switch( f->state ){ |
| 411 | case CLOSING: |
| 412 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 413 | /* fall through */ |
| 414 | case CLOSED: |
| 415 | f->state = CLOSED; |
| 416 | if( f->callbacks->finished ) |
| 417 | (*f->callbacks->finished)(f); |
| 418 | break; |
| 419 | |
| 420 | case STOPPING: |
| 421 | case REQSENT: |
| 422 | case ACKRCVD: |
| 423 | case ACKSENT: |
| 424 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 425 | /* fall through */ |
| 426 | case STOPPED: |
| 427 | f->state = STOPPED; |
| 428 | if( f->callbacks->finished ) |
| 429 | (*f->callbacks->finished)(f); |
| 430 | break; |
| 431 | |
| 432 | case OPENED: |
| 433 | if( f->callbacks->down ) |
| 434 | (*f->callbacks->down)(f); |
| 435 | |
| 436 | /* Init restart counter, send Terminate-Request */ |
| 437 | f->retransmits = f->maxtermtransmits; |
| 438 | fsm_sdata(f, TERMREQ, f->reqid = ++f->id, |
| 439 | (u_char *) f->term_reason, f->term_reason_len); |
| 440 | TIMEOUT(fsm_timeout, f, f->timeouttime); |
| 441 | --f->retransmits; |
| 442 | |
| 443 | f->state = STOPPING; |
| 444 | break; |
| 445 | |
| 446 | default: |
| 447 | FSMDEBUG((LOG_INFO, "%s: Protocol-reject event in state %d!\n", |
| 448 | PROTO_NAME(f), f->state)); |
| 449 | } |
| 450 | } |
| 451 | |
| 452 | |
| 453 | |
| 454 | |
| 455 | |
| 456 | /**********************************/ |
| 457 | /*** LOCAL FUNCTION DEFINITIONS ***/ |
| 458 | /**********************************/ |
| 459 | |
| 460 | /* |
| 461 | * fsm_timeout - Timeout expired. |
| 462 | */ |
| 463 | static void fsm_timeout(void *arg) |
| 464 | { |
| 465 | fsm *f = (fsm *) arg; |
| 466 | |
| 467 | switch (f->state) { |
| 468 | case CLOSING: |
| 469 | case STOPPING: |
| 470 | if( f->retransmits <= 0 ){ |
| 471 | FSMDEBUG((LOG_WARNING, "%s: timeout sending Terminate-Request state=%d\n", |
| 472 | PROTO_NAME(f), f->state)); |
| 473 | /* |
| 474 | * We've waited for an ack long enough. Peer probably heard us. |
| 475 | */ |
| 476 | f->state = (f->state == CLOSING)? CLOSED: STOPPED; |
| 477 | if( f->callbacks->finished ) |
| 478 | (*f->callbacks->finished)(f); |
| 479 | } else { |
| 480 | FSMDEBUG((LOG_WARNING, "%s: timeout resending Terminate-Requests state=%d\n", |
| 481 | PROTO_NAME(f), f->state)); |
| 482 | /* Send Terminate-Request */ |
| 483 | fsm_sdata(f, TERMREQ, f->reqid = ++f->id, |
| 484 | (u_char *) f->term_reason, f->term_reason_len); |
| 485 | TIMEOUT(fsm_timeout, f, f->timeouttime); |
| 486 | --f->retransmits; |
| 487 | } |
| 488 | break; |
| 489 | |
| 490 | case REQSENT: |
| 491 | case ACKRCVD: |
| 492 | case ACKSENT: |
| 493 | if (f->retransmits <= 0) { |
| 494 | FSMDEBUG((LOG_WARNING, "%s: timeout sending Config-Requests state=%d\n", |
| 495 | PROTO_NAME(f), f->state)); |
| 496 | f->state = STOPPED; |
| 497 | if( (f->flags & OPT_PASSIVE) == 0 && f->callbacks->finished ) |
| 498 | (*f->callbacks->finished)(f); |
| 499 | |
| 500 | } else { |
| 501 | FSMDEBUG((LOG_WARNING, "%s: timeout resending Config-Request state=%d\n", |
| 502 | PROTO_NAME(f), f->state)); |
| 503 | /* Retransmit the configure-request */ |
| 504 | if (f->callbacks->retransmit) |
| 505 | (*f->callbacks->retransmit)(f); |
| 506 | fsm_sconfreq(f, 1); /* Re-send Configure-Request */ |
| 507 | if( f->state == ACKRCVD ) |
| 508 | f->state = REQSENT; |
| 509 | } |
| 510 | break; |
| 511 | |
| 512 | default: |
| 513 | FSMDEBUG((LOG_INFO, "%s: Timeout event in state %d!\n", |
| 514 | PROTO_NAME(f), f->state)); |
| 515 | } |
| 516 | } |
| 517 | |
| 518 | |
| 519 | /* |
| 520 | * fsm_rconfreq - Receive Configure-Request. |
| 521 | */ |
| 522 | static void fsm_rconfreq(fsm *f, u_char id, u_char *inp, int len) |
| 523 | { |
| 524 | int code, reject_if_disagree; |
| 525 | |
| 526 | FSMDEBUG((LOG_INFO, "fsm_rconfreq(%s): Rcvd id %d state=%d\n", |
| 527 | PROTO_NAME(f), id, f->state)); |
| 528 | switch( f->state ){ |
| 529 | case CLOSED: |
| 530 | /* Go away, we're closed */ |
| 531 | fsm_sdata(f, TERMACK, id, NULL, 0); |
| 532 | return; |
| 533 | case CLOSING: |
| 534 | case STOPPING: |
| 535 | return; |
| 536 | |
| 537 | case OPENED: |
| 538 | /* Go down and restart negotiation */ |
| 539 | if( f->callbacks->down ) |
| 540 | (*f->callbacks->down)(f); /* Inform upper layers */ |
| 541 | fsm_sconfreq(f, 0); /* Send initial Configure-Request */ |
| 542 | break; |
| 543 | |
| 544 | case STOPPED: |
| 545 | /* Negotiation started by our peer */ |
| 546 | fsm_sconfreq(f, 0); /* Send initial Configure-Request */ |
| 547 | f->state = REQSENT; |
| 548 | break; |
| 549 | } |
| 550 | |
| 551 | /* |
| 552 | * Pass the requested configuration options |
| 553 | * to protocol-specific code for checking. |
| 554 | */ |
| 555 | if (f->callbacks->reqci){ /* Check CI */ |
| 556 | reject_if_disagree = (f->nakloops >= f->maxnakloops); |
| 557 | code = (*f->callbacks->reqci)(f, inp, &len, reject_if_disagree); |
| 558 | } |
| 559 | else if (len) |
| 560 | code = CONFREJ; /* Reject all CI */ |
| 561 | else |
| 562 | code = CONFACK; |
| 563 | |
| 564 | /* send the Ack, Nak or Rej to the peer */ |
| 565 | fsm_sdata(f, (u_char)code, id, inp, len); |
| 566 | |
| 567 | if (code == CONFACK) { |
| 568 | if (f->state == ACKRCVD) { |
| 569 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 570 | f->state = OPENED; |
| 571 | if (f->callbacks->up) |
| 572 | (*f->callbacks->up)(f); /* Inform upper layers */ |
| 573 | } |
| 574 | else |
| 575 | f->state = ACKSENT; |
| 576 | f->nakloops = 0; |
| 577 | } |
| 578 | else { |
| 579 | /* we sent CONFACK or CONFREJ */ |
| 580 | if (f->state != ACKRCVD) |
| 581 | f->state = REQSENT; |
| 582 | if( code == CONFNAK ) |
| 583 | ++f->nakloops; |
| 584 | } |
| 585 | } |
| 586 | |
| 587 | |
| 588 | /* |
| 589 | * fsm_rconfack - Receive Configure-Ack. |
| 590 | */ |
| 591 | static void fsm_rconfack(fsm *f, int id, u_char *inp, int len) |
| 592 | { |
| 593 | FSMDEBUG((LOG_INFO, "fsm_rconfack(%s): Rcvd id %d state=%d\n", |
| 594 | PROTO_NAME(f), id, f->state)); |
| 595 | |
| 596 | if (id != f->reqid || f->seen_ack) /* Expected id? */ |
| 597 | return; /* Nope, toss... */ |
| 598 | if( !(f->callbacks->ackci? (*f->callbacks->ackci)(f, inp, len): |
| 599 | (len == 0)) ){ |
| 600 | /* Ack is bad - ignore it */ |
| 601 | FSMDEBUG((LOG_INFO, "%s: received bad Ack (length %d)\n", |
| 602 | PROTO_NAME(f), len)); |
| 603 | return; |
| 604 | } |
| 605 | f->seen_ack = 1; |
| 606 | |
| 607 | switch (f->state) { |
| 608 | case CLOSED: |
| 609 | case STOPPED: |
| 610 | fsm_sdata(f, TERMACK, (u_char)id, NULL, 0); |
| 611 | break; |
| 612 | |
| 613 | case REQSENT: |
| 614 | f->state = ACKRCVD; |
| 615 | f->retransmits = f->maxconfreqtransmits; |
| 616 | break; |
| 617 | |
| 618 | case ACKRCVD: |
| 619 | /* Huh? an extra valid Ack? oh well... */ |
| 620 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 621 | fsm_sconfreq(f, 0); |
| 622 | f->state = REQSENT; |
| 623 | break; |
| 624 | |
| 625 | case ACKSENT: |
| 626 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 627 | f->state = OPENED; |
| 628 | f->retransmits = f->maxconfreqtransmits; |
| 629 | if (f->callbacks->up) |
| 630 | (*f->callbacks->up)(f); /* Inform upper layers */ |
| 631 | break; |
| 632 | |
| 633 | case OPENED: |
| 634 | /* Go down and restart negotiation */ |
| 635 | if (f->callbacks->down) |
| 636 | (*f->callbacks->down)(f); /* Inform upper layers */ |
| 637 | fsm_sconfreq(f, 0); /* Send initial Configure-Request */ |
| 638 | f->state = REQSENT; |
| 639 | break; |
| 640 | } |
| 641 | } |
| 642 | |
| 643 | |
| 644 | /* |
| 645 | * fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject. |
| 646 | */ |
| 647 | static void fsm_rconfnakrej(fsm *f, int code, int id, u_char *inp, int len) |
| 648 | { |
| 649 | int (*proc) (fsm *, u_char *, int); |
| 650 | int ret; |
| 651 | |
| 652 | FSMDEBUG((LOG_INFO, "fsm_rconfnakrej(%s): Rcvd id %d state=%d\n", |
| 653 | PROTO_NAME(f), id, f->state)); |
| 654 | |
| 655 | if (id != f->reqid || f->seen_ack) /* Expected id? */ |
| 656 | return; /* Nope, toss... */ |
| 657 | proc = (code == CONFNAK)? f->callbacks->nakci: f->callbacks->rejci; |
| 658 | if (!proc || !(ret = proc(f, inp, len))) { |
| 659 | /* Nak/reject is bad - ignore it */ |
| 660 | FSMDEBUG((LOG_INFO, "%s: received bad %s (length %d)\n", |
| 661 | PROTO_NAME(f), (code==CONFNAK? "Nak": "reject"), len)); |
| 662 | return; |
| 663 | } |
| 664 | f->seen_ack = 1; |
| 665 | |
| 666 | switch (f->state) { |
| 667 | case CLOSED: |
| 668 | case STOPPED: |
| 669 | fsm_sdata(f, TERMACK, (u_char)id, NULL, 0); |
| 670 | break; |
| 671 | |
| 672 | case REQSENT: |
| 673 | case ACKSENT: |
| 674 | /* They didn't agree to what we wanted - try another request */ |
| 675 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 676 | if (ret < 0) |
| 677 | f->state = STOPPED; /* kludge for stopping CCP */ |
| 678 | else |
| 679 | fsm_sconfreq(f, 0); /* Send Configure-Request */ |
| 680 | break; |
| 681 | |
| 682 | case ACKRCVD: |
| 683 | /* Got a Nak/reject when we had already had an Ack?? oh well... */ |
| 684 | UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */ |
| 685 | fsm_sconfreq(f, 0); |
| 686 | f->state = REQSENT; |
| 687 | break; |
| 688 | |
| 689 | case OPENED: |
| 690 | /* Go down and restart negotiation */ |
| 691 | if (f->callbacks->down) |
| 692 | (*f->callbacks->down)(f); /* Inform upper layers */ |
| 693 | fsm_sconfreq(f, 0); /* Send initial Configure-Request */ |
| 694 | f->state = REQSENT; |
| 695 | break; |
| 696 | } |
| 697 | } |
| 698 | |
| 699 | |
| 700 | /* |
| 701 | * fsm_rtermreq - Receive Terminate-Req. |
| 702 | */ |
| 703 | static void fsm_rtermreq(fsm *f, int id, u_char *p, int len) |
| 704 | { |
| 705 | FSMDEBUG((LOG_INFO, "fsm_rtermreq(%s): Rcvd id %d state=%d\n", |
| 706 | PROTO_NAME(f), id, f->state)); |
| 707 | |
| 708 | switch (f->state) { |
| 709 | case ACKRCVD: |
| 710 | case ACKSENT: |
| 711 | f->state = REQSENT; /* Start over but keep trying */ |
| 712 | break; |
| 713 | |
| 714 | case OPENED: |
| 715 | if (len > 0) { |
| 716 | FSMDEBUG((LOG_INFO, "%s terminated by peer (%x)\n", PROTO_NAME(f), p)); |
| 717 | } else { |
| 718 | FSMDEBUG((LOG_INFO, "%s terminated by peer\n", PROTO_NAME(f))); |
| 719 | } |
| 720 | if (f->callbacks->down) |
| 721 | (*f->callbacks->down)(f); /* Inform upper layers */ |
| 722 | f->retransmits = 0; |
| 723 | f->state = STOPPING; |
| 724 | TIMEOUT(fsm_timeout, f, f->timeouttime); |
| 725 | break; |
| 726 | } |
| 727 | |
| 728 | fsm_sdata(f, TERMACK, (u_char)id, NULL, 0); |
| 729 | } |
| 730 | |
| 731 | |
| 732 | /* |
| 733 | * fsm_rtermack - Receive Terminate-Ack. |
| 734 | */ |
| 735 | static void fsm_rtermack(fsm *f) |
| 736 | { |
| 737 | FSMDEBUG((LOG_INFO, "fsm_rtermack(%s): state=%d\n", |
| 738 | PROTO_NAME(f), f->state)); |
| 739 | |
| 740 | switch (f->state) { |
| 741 | case CLOSING: |
| 742 | UNTIMEOUT(fsm_timeout, f); |
| 743 | f->state = CLOSED; |
| 744 | if( f->callbacks->finished ) |
| 745 | (*f->callbacks->finished)(f); |
| 746 | break; |
| 747 | case STOPPING: |
| 748 | UNTIMEOUT(fsm_timeout, f); |
| 749 | f->state = STOPPED; |
| 750 | if( f->callbacks->finished ) |
| 751 | (*f->callbacks->finished)(f); |
| 752 | break; |
| 753 | |
| 754 | case ACKRCVD: |
| 755 | f->state = REQSENT; |
| 756 | break; |
| 757 | |
| 758 | case OPENED: |
| 759 | if (f->callbacks->down) |
| 760 | (*f->callbacks->down)(f); /* Inform upper layers */ |
| 761 | fsm_sconfreq(f, 0); |
| 762 | break; |
| 763 | } |
| 764 | } |
| 765 | |
| 766 | |
| 767 | /* |
| 768 | * fsm_rcoderej - Receive an Code-Reject. |
| 769 | */ |
| 770 | static void fsm_rcoderej(fsm *f, u_char *inp, int len) |
| 771 | { |
| 772 | u_char code, id; |
| 773 | |
| 774 | FSMDEBUG((LOG_INFO, "fsm_rcoderej(%s): state=%d\n", |
| 775 | PROTO_NAME(f), f->state)); |
| 776 | |
| 777 | if (len < HEADERLEN) { |
| 778 | FSMDEBUG((LOG_INFO, "fsm_rcoderej: Rcvd short Code-Reject packet!\n")); |
| 779 | return; |
| 780 | } |
| 781 | GETCHAR(code, inp); |
| 782 | GETCHAR(id, inp); |
| 783 | FSMDEBUG((LOG_WARNING, "%s: Rcvd Code-Reject for code %d, id %d\n", |
| 784 | PROTO_NAME(f), code, id)); |
| 785 | |
| 786 | if( f->state == ACKRCVD ) |
| 787 | f->state = REQSENT; |
| 788 | } |
| 789 | |
| 790 | |
| 791 | /* |
| 792 | * fsm_sconfreq - Send a Configure-Request. |
| 793 | */ |
| 794 | static void fsm_sconfreq(fsm *f, int retransmit) |
| 795 | { |
| 796 | u_char *outp; |
| 797 | int cilen; |
| 798 | |
| 799 | if( f->state != REQSENT && f->state != ACKRCVD && f->state != ACKSENT ){ |
| 800 | /* Not currently negotiating - reset options */ |
| 801 | if( f->callbacks->resetci ) |
| 802 | (*f->callbacks->resetci)(f); |
| 803 | f->nakloops = 0; |
| 804 | } |
| 805 | |
| 806 | if( !retransmit ){ |
| 807 | /* New request - reset retransmission counter, use new ID */ |
| 808 | f->retransmits = f->maxconfreqtransmits; |
| 809 | f->reqid = ++f->id; |
| 810 | } |
| 811 | |
| 812 | f->seen_ack = 0; |
| 813 | |
| 814 | /* |
| 815 | * Make up the request packet |
| 816 | */ |
| 817 | outp = outpacket_buf[f->unit] + PPP_HDRLEN + HEADERLEN; |
| 818 | if( f->callbacks->cilen && f->callbacks->addci ){ |
| 819 | cilen = (*f->callbacks->cilen)(f); |
| 820 | if( cilen > peer_mru[f->unit] - (int)HEADERLEN ) |
| 821 | cilen = peer_mru[f->unit] - HEADERLEN; |
| 822 | if (f->callbacks->addci) |
| 823 | (*f->callbacks->addci)(f, outp, &cilen); |
| 824 | } else |
| 825 | cilen = 0; |
| 826 | |
| 827 | /* send the request to our peer */ |
| 828 | fsm_sdata(f, CONFREQ, f->reqid, outp, cilen); |
| 829 | |
| 830 | /* start the retransmit timer */ |
| 831 | --f->retransmits; |
| 832 | TIMEOUT(fsm_timeout, f, f->timeouttime); |
| 833 | |
| 834 | FSMDEBUG((LOG_INFO, "%s: sending Configure-Request, id %d\n", |
| 835 | PROTO_NAME(f), f->reqid)); |
| 836 | } |
| 837 | |
| 838 | #endif /* PPP_SUPPORT */ |