main.c revision 37010
1/* 2 * User Process PPP 3 * 4 * Written by Toshiharu OHNO (tony-o@iij.ad.jp) 5 * 6 * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the Internet Initiative Japan, Inc. The name of the 14 * IIJ may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * $Id: main.c,v 1.132 1998/06/15 19:05:46 brian Exp $ 21 * 22 * TODO: 23 */ 24 25#include <sys/types.h> 26#include <sys/socket.h> 27#include <netinet/in.h> 28#include <netinet/in_systm.h> 29#include <netinet/ip.h> 30#include <sys/un.h> 31#include <net/if_tun.h> 32 33#include <errno.h> 34#include <fcntl.h> 35#include <paths.h> 36#include <signal.h> 37#include <stdio.h> 38#include <string.h> 39#include <sys/time.h> 40#include <termios.h> 41#include <unistd.h> 42 43#include "mbuf.h" 44#include "log.h" 45#include "defs.h" 46#include "id.h" 47#include "timer.h" 48#include "fsm.h" 49#include "lqr.h" 50#include "hdlc.h" 51#include "lcp.h" 52#include "ccp.h" 53#include "iplist.h" 54#include "throughput.h" 55#include "slcompress.h" 56#include "ipcp.h" 57#include "filter.h" 58#include "descriptor.h" 59#include "link.h" 60#include "mp.h" 61#include "bundle.h" 62#include "loadalias.h" 63#include "auth.h" 64#include "systems.h" 65#include "ip.h" 66#include "sig.h" 67#include "main.h" 68#include "tun.h" 69#include "server.h" 70#include "prompt.h" 71#include "chat.h" 72#include "chap.h" 73#include "datalink.h" 74 75#ifndef O_NONBLOCK 76#ifdef O_NDELAY 77#define O_NONBLOCK O_NDELAY 78#endif 79#endif 80 81static void DoLoop(struct bundle *); 82static void TerminalStop(int); 83static const char *ex_desc(int); 84 85static struct bundle *SignalBundle; 86static struct prompt *SignalPrompt; 87 88void 89Cleanup(int excode) 90{ 91 SignalBundle->CleaningUp = 1; 92 if (bundle_Phase(SignalBundle) != PHASE_DEAD) 93 bundle_Close(SignalBundle, NULL, CLOSE_STAYDOWN); 94} 95 96void 97AbortProgram(int excode) 98{ 99 server_Close(SignalBundle); 100 log_Printf(LogPHASE, "PPP Terminated (%s).\n", ex_desc(excode)); 101 bundle_Close(SignalBundle, NULL, CLOSE_STAYDOWN); 102 bundle_Destroy(SignalBundle); 103 log_Close(); 104 exit(excode); 105} 106 107static void 108CloseConnection(int signo) 109{ 110 /* NOTE, these are manual, we've done a setsid() */ 111 sig_signal(SIGINT, SIG_IGN); 112 log_Printf(LogPHASE, "Caught signal %d, abort connection(s)\n", signo); 113 bundle_Down(SignalBundle); 114 sig_signal(SIGINT, CloseConnection); 115} 116 117static void 118CloseSession(int signo) 119{ 120 log_Printf(LogPHASE, "Signal %d, terminate.\n", signo); 121 Cleanup(EX_TERM); 122} 123 124static pid_t BGPid = 0; 125 126static void 127KillChild(int signo) 128{ 129 log_Printf(LogPHASE, "Parent: Signal %d\n", signo); 130 kill(BGPid, SIGINT); 131} 132 133static void 134TerminalCont(int signo) 135{ 136 signal(SIGCONT, SIG_DFL); 137 prompt_Continue(SignalPrompt); 138} 139 140static void 141TerminalStop(int signo) 142{ 143 prompt_Suspend(SignalPrompt); 144 signal(SIGCONT, TerminalCont); 145 raise(SIGSTOP); 146} 147 148static void 149BringDownServer(int signo) 150{ 151 /* Drops all child prompts too ! */ 152 server_Close(SignalBundle); 153} 154 155static const char * 156ex_desc(int ex) 157{ 158 static char num[12]; /* Used immediately if returned */ 159 static const char *desc[] = { 160 "normal", "start", "sock", "modem", "dial", "dead", "done", 161 "reboot", "errdead", "hangup", "term", "nodial", "nologin" 162 }; 163 164 if (ex >= 0 && ex < sizeof desc / sizeof *desc) 165 return desc[ex]; 166 snprintf(num, sizeof num, "%d", ex); 167 return num; 168} 169 170static void 171Usage(void) 172{ 173 fprintf(stderr, 174 "Usage: ppp [-auto | -background | -direct | -dedicated | -ddial ]" 175#ifndef NOALIAS 176 " [ -alias ]" 177#endif 178 " [system]\n"); 179 exit(EX_START); 180} 181 182static char * 183ProcessArgs(int argc, char **argv, int *mode) 184{ 185 int optc, labelrequired, newmode; 186 char *cp; 187 188 optc = labelrequired = 0; 189 *mode = PHYS_INTERACTIVE; 190 while (argc > 0 && **argv == '-') { 191 cp = *argv + 1; 192 newmode = Nam2mode(cp); 193 switch (newmode) { 194 case PHYS_NONE: 195 if (strcmp(cp, "alias") == 0) { 196#ifndef NOALIAS 197 if (alias_Load() != 0) 198#endif 199 log_Printf(LogWARN, "Cannot load alias library\n"); 200 optc--; /* this option isn't exclusive */ 201 } else 202 Usage(); 203 break; 204 205 case PHYS_ALL: 206 Usage(); 207 break; 208 209 case PHYS_AUTO: 210 case PHYS_BACKGROUND: 211 case PHYS_DDIAL: 212 labelrequired = 1; 213 /* fall through */ 214 215 default: 216 *mode = newmode; 217 } 218 optc++; 219 argv++; 220 argc--; 221 } 222 223 if (argc > 1) { 224 fprintf(stderr, "You may specify only one system label.\n"); 225 exit(EX_START); 226 } 227 228 if (optc > 1) { 229 fprintf(stderr, "You may specify only one mode.\n"); 230 exit(EX_START); 231 } 232 233 if (labelrequired && argc != 1) { 234 fprintf(stderr, "Destination system must be specified in" 235 " auto, background or ddial mode.\n"); 236 exit(EX_START); 237 } 238 239 return argc == 1 ? *argv : NULL; /* Don't SetLabel yet ! */ 240} 241 242int 243main(int argc, char **argv) 244{ 245 char *name, *label; 246 int nfds, mode; 247 struct bundle *bundle; 248 struct prompt *prompt; 249 250 nfds = getdtablesize(); 251 if (nfds >= FD_SETSIZE) 252 /* 253 * If we've got loads of file descriptors, make sure they're all 254 * closed. If they aren't, we may end up with a seg fault when our 255 * `fd_set's get too big when select()ing ! 256 */ 257 while (--nfds > 2) 258 close(nfds); 259 260 name = strrchr(argv[0], '/'); 261 log_Open(name ? name + 1 : argv[0]); 262 263 label = ProcessArgs(argc - 1, argv + 1, &mode); 264 265#ifdef __FreeBSD__ 266 /* 267 * A FreeBSD hack to dodge a bug in the tty driver that drops output 268 * occasionally.... I must find the real reason some time. To display 269 * the dodgy behaviour, comment out this bit, make yourself a large 270 * routing table and then run ppp in interactive mode. The `show route' 271 * command will drop chunks of data !!! 272 */ 273 if (mode == PHYS_INTERACTIVE) { 274 close(STDIN_FILENO); 275 if (open(_PATH_TTY, O_RDONLY) != STDIN_FILENO) { 276 fprintf(stderr, "Cannot open %s for input !\n", _PATH_TTY); 277 return 2; 278 } 279 } 280#endif 281 282 /* Allow output for the moment (except in direct mode) */ 283 if (mode == PHYS_DIRECT) 284 prompt = NULL; 285 else { 286 SignalPrompt = prompt = prompt_Create(NULL, NULL, PROMPT_STD); 287 prompt_Printf(prompt, "Working in %s mode\n", mode2Nam(mode)); 288 } 289 290 ID0init(); 291 if (ID0realuid() != 0) { 292 char conf[200], *ptr; 293 294 snprintf(conf, sizeof conf, "%s/%s", _PATH_PPP, CONFFILE); 295 do { 296 if (!access(conf, W_OK)) { 297 log_Printf(LogALERT, "ppp: Access violation: Please protect %s\n", conf); 298 return -1; 299 } 300 ptr = conf + strlen(conf)-2; 301 while (ptr > conf && *ptr != '/') 302 *ptr-- = '\0'; 303 } while (ptr >= conf); 304 } 305 306 if (!system_IsValid(label, prompt, mode)) { 307 fprintf(stderr, "You may not use ppp in this mode with this label\n"); 308 if (mode == PHYS_DIRECT) { 309 const char *l; 310 l = label ? label : "default"; 311 log_Printf(LogWARN, "Label %s rejected -direct connection\n", l); 312 } 313 log_Close(); 314 return 1; 315 } 316 317 if ((bundle = bundle_Create(TUN_PREFIX, mode, (const char **)argv)) == NULL) { 318 log_Printf(LogWARN, "bundle_Create: %s\n", strerror(errno)); 319 return EX_START; 320 } 321 if (prompt) { 322 prompt->bundle = bundle; /* couldn't do it earlier */ 323 prompt_Printf(prompt, "Using interface: %s\n", bundle->ifp.Name); 324 } 325 SignalBundle = bundle; 326 327 if (system_Select(bundle, "default", CONFFILE, prompt, NULL) < 0) 328 prompt_Printf(prompt, "Warning: No default entry found in config file.\n"); 329 330 sig_signal(SIGHUP, CloseSession); 331 sig_signal(SIGTERM, CloseSession); 332 sig_signal(SIGINT, CloseConnection); 333 sig_signal(SIGQUIT, CloseSession); 334 sig_signal(SIGALRM, SIG_IGN); 335 signal(SIGPIPE, SIG_IGN); 336 337 if (mode == PHYS_INTERACTIVE) 338 sig_signal(SIGTSTP, TerminalStop); 339 340 sig_signal(SIGUSR2, BringDownServer); 341 342 if (label) { 343 /* 344 * Set label both before and after system_Select ! 345 * This way, "set enddisc label" works during system_Select, and we 346 * also end up with the correct label if we have embedded load 347 * commands. 348 */ 349 bundle_SetLabel(bundle, label); 350 if (system_Select(bundle, label, CONFFILE, prompt, NULL) < 0) { 351 prompt_Printf(prompt, "Destination system (%s) not found.\n", label); 352 AbortProgram(EX_START); 353 } 354 bundle_SetLabel(bundle, label); 355 if (mode == PHYS_AUTO && 356 bundle->ncp.ipcp.cfg.peer_range.ipaddr.s_addr == INADDR_ANY) { 357 prompt_Printf(prompt, "You must \"set ifaddr\" with a peer address " 358 "in label %s for auto mode.\n", label); 359 AbortProgram(EX_START); 360 } 361 } 362 363 if (mode != PHYS_INTERACTIVE) { 364 if (mode != PHYS_DIRECT) { 365 int bgpipe[2]; 366 pid_t bgpid; 367 368 if (mode == PHYS_BACKGROUND && pipe(bgpipe)) { 369 log_Printf(LogERROR, "pipe: %s\n", strerror(errno)); 370 AbortProgram(EX_SOCK); 371 } 372 373 bgpid = fork(); 374 if (bgpid == -1) { 375 log_Printf(LogERROR, "fork: %s\n", strerror(errno)); 376 AbortProgram(EX_SOCK); 377 } 378 379 if (bgpid) { 380 char c = EX_NORMAL; 381 382 if (mode == PHYS_BACKGROUND) { 383 close(bgpipe[1]); 384 BGPid = bgpid; 385 /* If we get a signal, kill the child */ 386 signal(SIGHUP, KillChild); 387 signal(SIGTERM, KillChild); 388 signal(SIGINT, KillChild); 389 signal(SIGQUIT, KillChild); 390 391 /* Wait for our child to close its pipe before we exit */ 392 if (read(bgpipe[0], &c, 1) != 1) { 393 prompt_Printf(prompt, "Child exit, no status.\n"); 394 log_Printf(LogPHASE, "Parent: Child exit, no status.\n"); 395 } else if (c == EX_NORMAL) { 396 prompt_Printf(prompt, "PPP enabled.\n"); 397 log_Printf(LogPHASE, "Parent: PPP enabled.\n"); 398 } else { 399 prompt_Printf(prompt, "Child failed (%s).\n", ex_desc((int) c)); 400 log_Printf(LogPHASE, "Parent: Child failed (%s).\n", 401 ex_desc((int) c)); 402 } 403 close(bgpipe[0]); 404 } 405 return c; 406 } else if (mode == PHYS_BACKGROUND) { 407 close(bgpipe[0]); 408 bundle->notify.fd = bgpipe[1]; 409 } 410 411 bundle_LockTun(bundle); /* we have a new pid */ 412 413 /* -auto, -dedicated, -ddial & -background */ 414 prompt_Destroy(prompt, 0); 415 close(STDOUT_FILENO); 416 close(STDERR_FILENO); 417 close(STDIN_FILENO); 418 setsid(); 419 } else { 420 /* -direct: STDIN_FILENO gets used by modem_Open */ 421 prompt_TtyInit(NULL); 422 close(STDOUT_FILENO); 423 close(STDERR_FILENO); 424 } 425 } else { 426 /* Interactive mode */ 427 close(STDERR_FILENO); 428 prompt_TtyInit(prompt); 429 prompt_TtyCommandMode(prompt); 430 prompt_Required(prompt); 431 } 432 433 log_Printf(LogPHASE, "PPP Started (%s mode).\n", mode2Nam(mode)); 434 DoLoop(bundle); 435 AbortProgram(EX_NORMAL); 436 437 return EX_NORMAL; 438} 439 440static void 441DoLoop(struct bundle *bundle) 442{ 443 fd_set rfds, wfds, efds; 444 int i, nfds; 445 446 do { 447 nfds = 0; 448 FD_ZERO(&rfds); 449 FD_ZERO(&wfds); 450 FD_ZERO(&efds); 451 452 /* All our datalinks, the tun device and the MP socket */ 453 descriptor_UpdateSet(&bundle->desc, &rfds, &wfds, &efds, &nfds); 454 455 /* All our prompts and the diagnostic socket */ 456 descriptor_UpdateSet(&server.desc, &rfds, NULL, NULL, &nfds); 457 458 if (bundle_IsDead(bundle)) 459 /* Don't select - we'll be here forever */ 460 break; 461 462 i = select(nfds, &rfds, &wfds, &efds, NULL); 463 464 if (i < 0 && errno != EINTR) { 465 log_Printf(LogERROR, "DoLoop: select(): %s\n", strerror(errno)); 466 if (log_IsKept(LogTIMER)) { 467 struct timeval t; 468 469 for (i = 0; i <= nfds; i++) { 470 if (FD_ISSET(i, &rfds)) { 471 log_Printf(LogTIMER, "Read set contains %d\n", i); 472 FD_CLR(i, &rfds); 473 t.tv_sec = t.tv_usec = 0; 474 if (select(nfds, &rfds, &wfds, &efds, &t) != -1) { 475 log_Printf(LogTIMER, "The culprit !\n"); 476 break; 477 } 478 } 479 if (FD_ISSET(i, &wfds)) { 480 log_Printf(LogTIMER, "Write set contains %d\n", i); 481 FD_CLR(i, &wfds); 482 t.tv_sec = t.tv_usec = 0; 483 if (select(nfds, &rfds, &wfds, &efds, &t) != -1) { 484 log_Printf(LogTIMER, "The culprit !\n"); 485 break; 486 } 487 } 488 if (FD_ISSET(i, &efds)) { 489 log_Printf(LogTIMER, "Error set contains %d\n", i); 490 FD_CLR(i, &efds); 491 t.tv_sec = t.tv_usec = 0; 492 if (select(nfds, &rfds, &wfds, &efds, &t) != -1) { 493 log_Printf(LogTIMER, "The culprit !\n"); 494 break; 495 } 496 } 497 } 498 } 499 break; 500 } 501 502 sig_Handle(); 503 504 if (i <= 0) 505 continue; 506 507 for (i = 0; i <= nfds; i++) 508 if (FD_ISSET(i, &efds)) { 509 log_Printf(LogALERT, "Exception detected on descriptor %d\n", i); 510 break; 511 } 512 513 if (i <= nfds) 514 break; 515 516 if (descriptor_IsSet(&server.desc, &rfds)) 517 descriptor_Read(&server.desc, bundle, &rfds); 518 519 if (descriptor_IsSet(&bundle->desc, &wfds)) 520 descriptor_Write(&bundle->desc, bundle, &wfds); 521 522 if (descriptor_IsSet(&bundle->desc, &rfds)) 523 descriptor_Read(&bundle->desc, bundle, &rfds); 524 525 } while (bundle_CleanDatalinks(bundle), !bundle_IsDead(bundle)); 526 527 log_Printf(LogDEBUG, "DoLoop done.\n"); 528} 529