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 1.39 1997/03/13 14:53:55 brian Exp $ 21 * 22 * TODO: 23 * o Add commands for traffic summary, version display, etc. 24 * o Add signal handler for misc controls. 25 */ 26 #include "fsm.h" 27 #include <fcntl.h> 28 #include <paths.h> 29 #include <sys/time.h> 30 #include <termios.h> 31 #include <signal.h> 32 #include <sys/wait.h> 33 #include <errno.h> 34 #include <netdb.h> 35 #include <unistd.h> 36 #include <sys/socket.h> 37 #include <arpa/inet.h> 38 #include <netinet/in_systm.h> 39 #include <netinet/ip.h> 40 #include "modem.h" 41 #include "os.h" 42 #include "hdlc.h" 43 #include "ccp.h" 44 #include "lcp.h" 45 #include "ipcp.h" 46 #include "vars.h" 47 #include "auth.h" 48 #include "filter.h" 49 #include "systems.h" 50 #include "ip.h" 51 #include "alias.h" 52 #include "sig.h" 53 54 #define LAUTH_M1 "Warning: No password entry for this host in ppp.secret\n" 55 #define LAUTH_M2 "Warning: All manipulation is allowed by anyone in the world\n" 56 57 #ifndef O_NONBLOCK 58 #ifdef O_NDELAY 59 #define O_NONBLOCK O_NDELAY 60 #endif 61 #endif 62 63 extern void VjInit(), AsyncInit(); 64 extern void AsyncInput(), IpOutput(); 65 extern int SelectSystem(); 66 67 extern void DecodeCommand(), Prompt(); 68 extern int aft_cmd; 69 extern int IsInteractive(); 70 extern struct in_addr ifnetmask; 71 static void DoLoop(void); 72 static void TerminalStop(); 73 74 static struct termios oldtio; /* Original tty mode */ 75 static struct termios comtio; /* Command level tty mode */ 76 int TermMode; 77 static int server; 78 static pid_t BGPid = 0; 79 struct sockaddr_in ifsin; 80 char pid_filename[128]; 81 82 static void 83 TtyInit() 84 { 85 struct termios newtio; 86 int stat; 87 88 stat = fcntl(0, F_GETFL, 0); 89 stat |= O_NONBLOCK; 90 fcntl(0, F_SETFL, stat); 91 newtio = oldtio; 92 newtio.c_lflag &= ~(ECHO|ISIG|ICANON); 93 newtio.c_iflag = 0; 94 newtio.c_oflag &= ~OPOST; 95 newtio.c_cc[VEOF] = _POSIX_VDISABLE; 96 newtio.c_cc[VINTR] = _POSIX_VDISABLE; 97 newtio.c_cc[VMIN] = 1; 98 newtio.c_cc[VTIME] = 0; 99 newtio.c_cflag |= CS8; 100 tcsetattr(0, TCSADRAIN, &newtio); 101 comtio = newtio; 102 } 103 104 /* 105 * Set tty into command mode. We allow canonical input and echo processing. 106 */ 107 void 108 TtyCommandMode(prompt) 109 int prompt; 110 { 111 struct termios newtio; 112 int stat; 113 114 if (!(mode & MODE_INTER)) 115 return; 116 tcgetattr(0, &newtio); 117 newtio.c_lflag |= (ECHO|ISIG|ICANON); 118 newtio.c_iflag = oldtio.c_iflag; 119 newtio.c_oflag |= OPOST; 120 tcsetattr(0, TCSADRAIN, &newtio); 121 stat = fcntl(0, F_GETFL, 0); 122 stat |= O_NONBLOCK; 123 fcntl(0, F_SETFL, stat); 124 TermMode = 0; 125 if(prompt) Prompt(0); 126 } 127 128 /* 129 * Set tty into terminal mode which is used while we invoke term command. 130 */ 131 void 132 TtyTermMode() 133 { 134 int stat; 135 136 tcsetattr(0, TCSADRAIN, &comtio); 137 stat = fcntl(0, F_GETFL, 0); 138 stat &= ~O_NONBLOCK; 139 fcntl(0, F_SETFL, stat); 140 TermMode = 1; 141 } 142 143 void 144 TtyOldMode() 145 { 146 int stat; 147 148 stat = fcntl(0, F_GETFL, 0); 149 stat &= ~O_NONBLOCK; 150 fcntl(0, F_SETFL, stat); 151 tcsetattr(0, TCSANOW, &oldtio); 152 } 153 154 void 155 Cleanup(excode) 156 int excode; 157 { 158 159 OsLinkdown(); 160 OsCloseLink(1); 161 sleep(1); 162 if (mode & (MODE_AUTO | MODE_BACKGROUND)) { 163 DeleteIfRoutes(1); 164 unlink(pid_filename); 165 } 166 OsInterfaceDown(1); 167 if (mode & MODE_BACKGROUND && BGFiledes[1] != -1) { 168 char c = EX_ERRDEAD; 169 if (write(BGFiledes[1],&c,1) == 1) 170 LogPrintf(LOG_PHASE_BIT,"Parent notified of failure.\n"); 171 else 172 LogPrintf(LOG_PHASE_BIT,"Failed to notify parent of failure.\n"); 173 close(BGFiledes[1]); 174 } 175 LogPrintf(LOG_PHASE_BIT, "PPP Terminated.\n"); 176 LogClose(); 177 if (server >= 0) { 178 close(server); 179 server = -1; 180 } 181 TtyOldMode(); 182 183 exit(excode); 184 } 185 186 static void 187 Hangup(signo) 188 int signo; 189 { 190 if (signo == SIGSEGV) { 191 LogPrintf(LOG_PHASE_BIT, "Signal %d, core dump.\n", signo); 192 LogClose(); 193 abort(); 194 } 195 if (BGPid) { 196 kill (BGPid, SIGTERM); 197 exit (EX_HANGUP); 198 } 199 else { 200 LogPrintf(LOG_PHASE_BIT, "Signal %d, hangup.\n", signo); 201 Cleanup(EX_HANGUP); 202 } 203 } 204 205 static void 206 CloseSession(signo) 207 int signo; 208 { 209 if (BGPid) { 210 kill (BGPid, SIGINT); 211 exit (EX_TERM); 212 } 213 else { 214 LogPrintf(LOG_PHASE_BIT, "Signal %d, terminate.\n", signo); 215 LcpClose(); 216 Cleanup(EX_TERM); 217 } 218 } 219 220 static void 221 TerminalCont() 222 { 223 pending_signal(SIGCONT, SIG_DFL); 224 pending_signal(SIGTSTP, TerminalStop); 225 TtyCommandMode(getpgrp() == tcgetpgrp(0)); 226 } 227 228 static void 229 TerminalStop(signo) 230 int signo; 231 { 232 pending_signal(SIGCONT, TerminalCont); 233 TtyOldMode(); 234 pending_signal(SIGTSTP, SIG_DFL); 235 kill(getpid(), signo); 236 } 237 238 239 void 240 Usage() 241 { 242 fprintf(stderr, 243 "Usage: ppp [-auto | -background | -direct | -dedicated | -ddial ] [ -alias ] [system]\n"); 244 exit(EX_START); 245 } 246 247 void 248 ProcessArgs(int argc, char **argv) 249 { 250 int optc; 251 char *cp; 252 253 optc = 0; 254 while (argc > 0 && **argv == '-') { 255 cp = *argv + 1; 256 if (strcmp(cp, "auto") == 0) 257 mode |= MODE_AUTO; 258 else if (strcmp(cp, "background") == 0) 259 mode |= MODE_BACKGROUND; 260 else if (strcmp(cp, "direct") == 0) 261 mode |= MODE_DIRECT; 262 else if (strcmp(cp, "dedicated") == 0) 263 mode |= MODE_DEDICATED; 264 else if (strcmp(cp, "ddial") == 0) 265 mode |= MODE_DDIAL|MODE_AUTO; 266 else if (strcmp(cp, "alias") == 0) { 267 mode |= MODE_ALIAS; 268 optc--; /* this option isn't exclusive */ 269 } 270 else 271 Usage(); 272 optc++; 273 argv++; argc--; 274 } 275 if (argc > 1) { 276 fprintf(stderr, "specify only one system label.\n"); 277 exit(EX_START); 278 } 279 if (argc == 1) dstsystem = *argv; 280 281 if (optc > 1) { 282 fprintf(stderr, "specify only one mode.\n"); 283 exit(EX_START); 284 } 285 } 286 287 static void 288 Greetings() 289 { 290 printf("User Process PPP. Written by Toshiharu OHNO.\r\n"); 291 fflush(stdout); 292 } 293 294 void 295 main(argc, argv) 296 int argc; 297 char **argv; 298 { 299 int tunno; 300 301 argc--; argv++; 302 303 mode = MODE_INTER; /* default operation is interactive mode */ 304 netfd = server = modem = tun_in = -1; 305 ProcessArgs(argc, argv); 306 Greetings(); 307 GetUid(); 308 IpcpDefAddress(); 309 InitAlias(); 310 311 if (SelectSystem("default", CONFFILE) < 0) { 312 fprintf(stderr, "Warning: No default entry is given in config file.\n"); 313 } 314 315 if (LogOpen()) 316 exit(EX_START); 317 318 switch ( LocalAuthInit() ) { 319 case NOT_FOUND: 320 fprintf(stderr,LAUTH_M1); 321 fprintf(stderr,LAUTH_M2); 322 fflush (stderr); 323 /* Fall down */ 324 case VALID: 325 VarLocalAuth = LOCAL_AUTH; 326 break; 327 default: 328 break; 329 } 330 331 if (OpenTunnel(&tunno) < 0) { 332 perror("open_tun"); 333 exit(EX_START); 334 } 335 336 if (mode & (MODE_AUTO|MODE_DIRECT|MODE_DEDICATED|MODE_BACKGROUND)) 337 mode &= ~MODE_INTER; 338 if (mode & MODE_INTER) { 339 printf("Interactive mode\n"); 340 netfd = STDIN_FILENO; 341 } else if (mode & MODE_AUTO) { 342 printf("Automatic Dialer mode\n"); 343 if (dstsystem == NULL) { 344 fprintf(stderr, 345 "Destination system must be specified in auto or ddial mode.\n"); 346 exit(EX_START); 347 } 348 } else if (mode & MODE_BACKGROUND) { 349 printf("Background mode\n"); 350 if (dstsystem == NULL) { 351 fprintf(stderr, "Destination system must be specified in background mode.\n"); 352 exit(EX_START); 353 } 354 } 355 356 tcgetattr(0, &oldtio); /* Save original tty mode */ 357 358 pending_signal(SIGHUP, LogReOpen); 359 pending_signal(SIGTERM, CloseSession); 360 pending_signal(SIGINT, CloseSession); 361 pending_signal(SIGQUIT, CloseSession); 362 #ifdef SIGSEGV 363 signal(SIGSEGV, Hangup); 364 #endif 365 #ifdef SIGPIPE 366 signal(SIGPIPE, Hangup); 367 #endif 368 #ifdef SIGALRM 369 pending_signal(SIGALRM, SIG_IGN); 370 #endif 371 if(mode & MODE_INTER) 372 { 373 #ifdef SIGTSTP 374 pending_signal(SIGTSTP, TerminalStop); 375 #endif 376 #ifdef SIGTTIN 377 pending_signal(SIGTTIN, TerminalStop); 378 #endif 379 #ifdef SIGTTOU 380 pending_signal(SIGTTOU, SIG_IGN); 381 #endif 382 } 383 384 if (dstsystem) { 385 if (SelectSystem(dstsystem, CONFFILE) < 0) { 386 fprintf(stderr, "Destination system not found in conf file.\n"); 387 Cleanup(EX_START); 388 } 389 if ((mode & MODE_AUTO) && DefHisAddress.ipaddr.s_addr == INADDR_ANY) { 390 fprintf(stderr, "Must specify dstaddr with auto or ddial mode.\n"); 391 Cleanup(EX_START); 392 } 393 } 394 if (mode & MODE_DIRECT) 395 printf("Packet mode enabled.\n"); 396 397 #ifdef notdef 398 if (mode & MODE_AUTO) { 399 OsSetIpaddress(IpcpInfo.want_ipaddr, IpcpInfo.his_ipaddr, ifnetmask); 400 } 401 #endif 402 403 if (!(mode & MODE_INTER)) { 404 int port = SERVER_PORT + tunno; 405 if (mode & MODE_BACKGROUND) { 406 if (pipe (BGFiledes)) { 407 perror("pipe"); 408 Cleanup(EX_SOCK); 409 } 410 } 411 else { 412 /* 413 * Create server socket and listen at there. 414 */ 415 server = socket(PF_INET, SOCK_STREAM, 0); 416 if (server < 0) { 417 perror("socket"); 418 Cleanup(EX_SOCK); 419 } 420 ifsin.sin_family = AF_INET; 421 ifsin.sin_addr.s_addr = INADDR_ANY; 422 ifsin.sin_port = htons(port); 423 if (bind(server, (struct sockaddr *) &ifsin, sizeof(ifsin)) < 0) { 424 perror("bind"); 425 if (errno == EADDRINUSE) 426 fprintf(stderr, "Wait for a while, then try again.\n"); 427 Cleanup(EX_SOCK); 428 } 429 listen(server, 5); 430 } 431 432 DupLog(); 433 if (!(mode & MODE_DIRECT)) { 434 int fd; 435 char pid[32]; 436 pid_t bgpid; 437 438 bgpid = fork (); 439 if (bgpid == -1) { 440 perror ("fork"); 441 Cleanup (EX_SOCK); 442 } 443 if (bgpid) { 444 char c = EX_NORMAL; 445 446 if (mode & MODE_BACKGROUND) { 447 /* Wait for our child to close its pipe before we exit. */ 448 BGPid = bgpid; 449 close (BGFiledes[1]); 450 if (read(BGFiledes[0], &c, 1) != 1) 451 LogPrintf (LOG_PHASE_BIT, "Parent: Child exit, no status.\n"); 452 else if (c == EX_NORMAL) 453 LogPrintf (LOG_PHASE_BIT, "Parent: PPP enabled.\n"); 454 else 455 LogPrintf (LOG_PHASE_BIT, "Parent: Child failed %d.\n",(int)c); 456 close (BGFiledes[0]); 457 } 458 exit(c); 459 } else if (mode & MODE_BACKGROUND) 460 close(BGFiledes[0]); 461 462 snprintf(pid_filename, sizeof (pid_filename), "%s/ppp.tun%d.pid", 463 _PATH_VARRUN, tunno); 464 unlink(pid_filename); 465 snprintf(pid, sizeof(pid), "%d\n", (int)getpid()); 466 467 if ((fd = open(pid_filename, O_RDWR|O_CREAT, 0666)) != -1) 468 { 469 write(fd, pid, strlen(pid)); 470 close(fd); 471 } 472 } 473 if (server >= 0) 474 LogPrintf(LOG_PHASE_BIT, "Listening at %d.\n", port); 475 #ifdef DOTTYINIT 476 if (mode & (MODE_DIRECT|MODE_DEDICATED)) { /* } */ 477 #else 478 if (mode & MODE_DIRECT) { 479 #endif 480 TtyInit(); 481 } else { 482 int fd; 483 484 setsid(); /* detach control tty */ 485 if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { 486 (void)dup2(fd, STDIN_FILENO); 487 (void)dup2(fd, STDOUT_FILENO); 488 (void)dup2(fd, STDERR_FILENO); 489 if (fd > 2) 490 (void)close (fd); 491 } 492 } 493 } else { 494 TtyInit(); 495 TtyCommandMode(1); 496 } 497 LogPrintf(LOG_PHASE_BIT, "PPP Started.\n"); 498 499 500 do 501 DoLoop(); 502 while (mode & MODE_DEDICATED); 503 504 Cleanup(EX_DONE); 505 } 506 507 /* 508 * Turn into packet mode, where we speak PPP. 509 */ 510 void 511 PacketMode() 512 { 513 if (RawModem(modem) < 0) { 514 fprintf(stderr, "Not connected.\r\n"); 515 return; 516 } 517 518 AsyncInit(); 519 VjInit(); 520 LcpInit(); 521 IpcpInit(); 522 CcpInit(); 523 LcpUp(); 524 525 if (mode & (MODE_DIRECT|MODE_DEDICATED)) 526 LcpOpen(OPEN_ACTIVE); 527 else 528 LcpOpen(VarOpenMode); 529 if ((mode & (MODE_INTER|MODE_AUTO)) == MODE_INTER) { 530 TtyCommandMode(1); 531 fprintf(stderr, "Packet mode.\r\n"); 532 aft_cmd = 1; 533 } 534 } 535 536 static void 537 ShowHelp() 538 { 539 fprintf(stderr, "The following commands are available:\r\n"); 540 fprintf(stderr, " ~p\tEnter to Packet mode\r\n"); 541 fprintf(stderr, " ~-\tDecrease log level\r\n"); 542 fprintf(stderr, " ~+\tIncrease log level\r\n"); 543 fprintf(stderr, " ~.\tTerminate program\r\n"); 544 fprintf(stderr, " ~?\tThis help\r\n"); 545 } 546 547 static void 548 ReadTty() 549 { 550 int n; 551 char ch; 552 static int ttystate; 553 #define MAXLINESIZE 200 554 char linebuff[MAXLINESIZE]; 555 556 #ifdef DEBUG 557 logprintf("termode = %d, netfd = %d, mode = %d\n", TermMode, netfd, mode); 558 #endif 559 if (!TermMode) { 560 n = read(netfd, linebuff, sizeof(linebuff)-1); 561 aft_cmd = 1; 562 if (n > 0) { 563 DecodeCommand(linebuff, n, 1); 564 } else { 565 #ifdef DEBUG 566 logprintf("connection closed.\n"); 567 #endif 568 close(netfd); 569 netfd = -1; 570 mode &= ~MODE_INTER; 571 } 572 return; 573 } 574 575 /* 576 * We are in terminal mode, decode special sequences 577 */ 578 n = read(0, &ch, 1); 579 #ifdef DEBUG 580 logprintf("got %d bytes\n", n); 581 #endif 582 583 if (n > 0) { 584 switch (ttystate) { 585 case 0: 586 if (ch == '~') 587 ttystate++; 588 else 589 write(modem, &ch, n); 590 break; 591 case 1: 592 switch (ch) { 593 case '?': 594 ShowHelp(); 595 break; 596 case '-': 597 if (loglevel > 0) { 598 loglevel--; 599 fprintf(stderr, "New loglevel is %d\r\n", loglevel); 600 } 601 break; 602 case '+': 603 loglevel++; 604 fprintf(stderr, "New loglevel is %d\r\n", loglevel); 605 break; 606 #ifdef DEBUG 607 case 'm': 608 ShowMemMap(); 609 break; 610 #endif 611 case 'p': 612 /* 613 * XXX: Should check carrier. 614 */ 615 if (LcpFsm.state <= ST_CLOSED) { 616 VarOpenMode = OPEN_ACTIVE; 617 PacketMode(); 618 } 619 break; 620 #ifdef DEBUG 621 case 't': 622 ShowTimers(); 623 break; 624 #endif 625 case '.': 626 TermMode = 1; 627 TtyCommandMode(1); 628 break; 629 default: 630 if (write(modem, &ch, n) < 0) 631 fprintf(stderr, "err in write.\r\n"); 632 break; 633 } 634 ttystate = 0; 635 break; 636 } 637 } 638 } 639 640 641 /* 642 * Here, we'll try to detect HDLC frame 643 */ 644 645 static char *FrameHeaders[] = { 646 "\176\377\003\300\041", 647 "\176\377\175\043\300\041", 648 "\176\177\175\043\100\041", 649 "\176\175\337\175\043\300\041", 650 "\176\175\137\175\043\100\041", 651 NULL, 652 }; 653 654 u_char * 655 HdlcDetect(cp, n) 656 u_char *cp; 657 int n; 658 { 659 char *ptr, *fp, **hp; 660 661 cp[n] = '\0'; /* be sure to null terminated */ 662 ptr = NULL; 663 for (hp = FrameHeaders; *hp; hp++) { 664 fp = *hp; 665 if (DEV_IS_SYNC) 666 fp++; 667 ptr = strstr((char *)cp, fp); 668 if (ptr) 669 break; 670 } 671 return((u_char *)ptr); 672 } 673 674 static struct pppTimer RedialTimer; 675 676 static void 677 RedialTimeout() 678 { 679 StopTimer(&RedialTimer); 680 LogPrintf(LOG_PHASE_BIT, "Redialing timer expired.\n"); 681 } 682 683 static void 684 StartRedialTimer() 685 { 686 StopTimer(&RedialTimer); 687 688 if (VarRedialTimeout) { 689 LogPrintf(LOG_PHASE_BIT, "Enter pause for redialing.\n"); 690 RedialTimer.state = TIMER_STOPPED; 691 692 if (VarRedialTimeout > 0) 693 RedialTimer.load = VarRedialTimeout * SECTICKS; 694 else 695 RedialTimer.load = (random() % REDIAL_PERIOD) * SECTICKS; 696 697 RedialTimer.func = RedialTimeout; 698 StartTimer(&RedialTimer); 699 } 700 } 701 702 703 static void 704 DoLoop() 705 { 706 fd_set rfds, wfds, efds; 707 int pri, i, n, wfd, nfds; 708 struct sockaddr_in hisaddr; 709 struct timeval timeout, *tp; 710 int ssize = sizeof(hisaddr); 711 u_char *cp; 712 u_char rbuff[MAX_MRU]; 713 int dial_up; 714 int tries; 715 int qlen; 716 pid_t pgroup; 717 718 pgroup = getpgrp(); 719 720 if (mode & (MODE_DIRECT|MODE_BACKGROUND)) { 721 modem = OpenModem(mode); 722 LogPrintf(LOG_PHASE_BIT, "Packet mode enabled\n"); 723 fflush(stderr); 724 PacketMode(); 725 } else if (mode & MODE_DEDICATED) { 726 if (modem < 0) 727 modem = OpenModem(mode); 728 } 729 730 fflush(stdout); 731 732 timeout.tv_sec = 0; 733 timeout.tv_usec = 0; 734 735 if (mode & MODE_BACKGROUND) 736 dial_up = TRUE; /* Bring the line up */ 737 else 738 dial_up = FALSE; /* XXXX */ 739 tries = 0; 740 for (;;) { 741 nfds = 0; 742 FD_ZERO(&rfds); FD_ZERO(&wfds); FD_ZERO(&efds); 743 744 /* 745 * If the link is down and we're in DDIAL mode, bring it back 746 * up. 747 */ 748 if (mode & MODE_DDIAL && LcpFsm.state <= ST_CLOSED) 749 dial_up = TRUE; 750 751 /* 752 * If Ip packet for output is enqueued and require dial up, 753 * Just do it! 754 */ 755 if ( dial_up && RedialTimer.state != TIMER_RUNNING ) { /* XXX */ 756 #ifdef DEBUG 757 logprintf("going to dial: modem = %d\n", modem); 758 #endif 759 modem = OpenModem(mode); 760 if (modem < 0) { 761 StartRedialTimer(); 762 } else { 763 tries++; 764 LogPrintf(LOG_CHAT_BIT, "Dial attempt %u\n", tries); 765 if (DialModem()) { 766 sleep(1); /* little pause to allow peer starts */ 767 ModemTimeout(); 768 PacketMode(); 769 dial_up = FALSE; 770 tries = 0; 771 } else { 772 CloseModem(); 773 /* Dial failed. Keep quite during redial wait period. */ 774 StartRedialTimer(); 775 776 if (VarDialTries && tries >= VarDialTries) { 777 dial_up = FALSE; 778 tries = 0; 779 } 780 } 781 } 782 } 783 qlen = ModemQlen(); 784 785 if (qlen == 0) { 786 IpStartOutput(); 787 qlen = ModemQlen(); 788 } 789 790 if (modem >= 0) { 791 if (modem + 1 > nfds) 792 nfds = modem + 1; 793 FD_SET(modem, &rfds); 794 FD_SET(modem, &efds); 795 if (qlen > 0) { 796 FD_SET(modem, &wfds); 797 } 798 } 799 if (server >= 0) { 800 if (server + 1 > nfds) 801 nfds = server + 1; 802 FD_SET(server, &rfds); 803 } 804 805 /* *** IMPORTANT *** 806 * 807 * CPU is serviced every TICKUNIT micro seconds. 808 * This value must be chosen with great care. If this values is 809 * too big, it results loss of characters from modem and poor responce. 810 * If this values is too small, ppp process eats many CPU time. 811 */ 812 #ifndef SIGALRM 813 usleep(TICKUNIT); 814 TimerService(); 815 #else 816 handle_signals(); 817 #endif 818 819 /* If there are aren't many packets queued, look for some more. */ 820 if (qlen < 20 && tun_in >= 0) { 821 if (tun_in + 1 > nfds) 822 nfds = tun_in + 1; 823 FD_SET(tun_in, &rfds); 824 } 825 826 if (netfd >= 0) { 827 if (netfd + 1 > nfds) 828 nfds = netfd + 1; 829 FD_SET(netfd, &rfds); 830 FD_SET(netfd, &efds); 831 } 832 833 #ifndef SIGALRM 834 /* 835 * Normally, select() will not block because modem is writable. 836 * In AUTO mode, select will block until we find packet from tun 837 */ 838 tp = (RedialTimer.state == TIMER_RUNNING)? &timeout : NULL; 839 i = select(nfds, &rfds, &wfds, &efds, tp); 840 #else 841 /* 842 * When SIGALRM timer is running, a select function will be 843 * return -1 and EINTR after a Time Service signal hundler 844 * is done. If the redial timer is not running and we are 845 * trying to dial, poll with a 0 value timer. 846 */ 847 tp = (dial_up && RedialTimer.state != TIMER_RUNNING) ? &timeout : NULL; 848 i = select(nfds, &rfds, &wfds, &efds, tp); 849 #endif 850 851 if ( i == 0 ) { 852 continue; 853 } 854 855 if ( i < 0 ) { 856 if ( errno == EINTR ) { 857 handle_signals(); 858 continue; 859 } 860 perror("select"); 861 break; 862 } 863 864 if ((netfd >= 0 && FD_ISSET(netfd, &efds)) || (modem >= 0 && FD_ISSET(modem, &efds))) { 865 logprintf("Exception detected.\n"); 866 break; 867 } 868 869 if (server >= 0 && FD_ISSET(server, &rfds)) { 870 #ifdef DEBUG 871 logprintf("connected to client.\n"); 872 #endif 873 wfd = accept(server, (struct sockaddr *)&hisaddr, &ssize); 874 if (netfd >= 0) { 875 write(wfd, "already in use.\n", 16); 876 close(wfd); 877 continue; 878 } else 879 netfd = wfd; 880 if (dup2(netfd, 1) < 0) 881 perror("dup2"); 882 mode |= MODE_INTER; 883 Greetings(); 884 switch ( LocalAuthInit() ) { 885 case NOT_FOUND: 886 fprintf(stdout,LAUTH_M1); 887 fprintf(stdout,LAUTH_M2); 888 fflush(stdout); 889 /* Fall down */ 890 case VALID: 891 VarLocalAuth = LOCAL_AUTH; 892 break; 893 default: 894 break; 895 } 896 (void) IsInteractive(); 897 Prompt(0); 898 } 899 900 if ((mode & MODE_INTER) && (netfd >= 0 && FD_ISSET(netfd, &rfds)) && 901 ((mode & MODE_AUTO) || pgroup == tcgetpgrp(0))) { 902 /* something to read from tty */ 903 ReadTty(); 904 } 905 if (modem >= 0) { 906 if (FD_ISSET(modem, &wfds)) { /* ready to write into modem */ 907 ModemStartOutput(modem); 908 } 909 if (FD_ISSET(modem, &rfds)) { /* something to read from modem */ 910 if (LcpFsm.state <= ST_CLOSED) 911 usleep(10000); 912 n = read(modem, rbuff, sizeof(rbuff)); 913 if ((mode & MODE_DIRECT) && n <= 0) { 914 DownConnection(); 915 } else 916 LogDumpBuff(LOG_ASYNC, "ReadFromModem", rbuff, n); 917 918 if (LcpFsm.state <= ST_CLOSED) { 919 /* 920 * In dedicated mode, we just discard input until LCP is started. 921 */ 922 if (!(mode & MODE_DEDICATED)) { 923 cp = HdlcDetect(rbuff, n); 924 if (cp) { 925 /* 926 * LCP packet is detected. Turn ourselves into packet mode. 927 */ 928 if (cp != rbuff) { 929 write(1, rbuff, cp - rbuff); 930 write(1, "\r\n", 2); 931 } 932 PacketMode(); 933 #ifdef notdef 934 AsyncInput(cp, n - (cp - rbuff)); 935 #endif 936 } else 937 write(1, rbuff, n); 938 } 939 } else { 940 if (n > 0) 941 AsyncInput(rbuff, n); 942 #ifdef notdef 943 continue; /* THIS LINE RESULT AS POOR PERFORMANCE */ 944 #endif 945 } 946 } 947 } 948 949 if (tun_in >= 0 && FD_ISSET(tun_in, &rfds)) { /* something to read from tun */ 950 n = read(tun_in, rbuff, sizeof(rbuff)); 951 if (n < 0) { 952 perror("read from tun"); 953 continue; 954 } 955 /* 956 * Process on-demand dialup. Output packets are queued within tunnel 957 * device until IPCP is opened. 958 */ 959 if (LcpFsm.state <= ST_CLOSED && (mode & MODE_AUTO)) { 960 pri = PacketCheck(rbuff, n, FL_DIAL); 961 if (pri >= 0) { 962 if (mode & MODE_ALIAS) { 963 PacketAliasOut((struct ip *)rbuff); 964 n = ntohs(((struct ip *)rbuff)->ip_len); 965 } 966 IpEnqueue(pri, rbuff, n); 967 dial_up = TRUE; /* XXX */ 968 } 969 continue; 970 } 971 pri = PacketCheck(rbuff, n, FL_OUT); 972 if (pri >= 0) { 973 if (mode & MODE_ALIAS) { 974 PacketAliasOut((struct ip *)rbuff); 975 n = ntohs(((struct ip *)rbuff)->ip_len); 976 } 977 IpEnqueue(pri, rbuff, n); 978 } 979 } 980 } 981 logprintf("job done.\n"); 982 } 983