1/* $OpenBSD: tip.c,v 1.30 2006/08/18 03:06:18 jason Exp $ */ 2/* $NetBSD: tip.c,v 1.13 1997/04/20 00:03:05 mellon Exp $ */ 3 4/* 5 * Copyright (c) 1983, 1993 6 * The Regents of the University of California. 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 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD$"); 35 36#ifndef lint 37static const char copyright[] = 38"@(#) Copyright (c) 1983, 1993\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40#endif /* not lint */ 41 42#ifndef lint 43#if 0 44static char sccsid[] = "@(#)tip.c 8.1 (Berkeley) 6/6/93"; 45static const char rcsid[] = "$OpenBSD: tip.c,v 1.30 2006/08/18 03:06:18 jason Exp $"; 46#endif 47#endif /* not lint */ 48 49/* 50 * tip - UNIX link to other systems 51 * tip [-v] [-speed] system-name 52 * or 53 * cu phone-number [-s speed] [-l line] [-a acu] 54 */ 55#include "tip.h" 56#include "pathnames.h" 57 58int disc = TTYDISC; /* tip normally runs this way */ 59char PNbuf[256]; /* This limits the size of a number */ 60 61static void intprompt(int); 62static void tipin(void); 63static int escape(void); 64 65int 66main(int argc, char *argv[]) 67{ 68 char *sys = NOSTR, sbuf[12], *p; 69 int i; 70 71 /* XXX preserve previous braindamaged behavior */ 72 setboolean(value(DC), TRUE); 73 74 gid = getgid(); 75 egid = getegid(); 76 uid = getuid(); 77 euid = geteuid(); 78 if (equal(__progname, "cu")) { 79 cumode = 1; 80 cumain(argc, argv); 81 goto cucommon; 82 } 83 84 if (argc > 4) { 85 fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n"); 86 exit(1); 87 } 88 if (!isatty(0)) { 89 fprintf(stderr, "%s: must be interactive\n", __progname); 90 exit(1); 91 } 92 93 for (; argc > 1; argv++, argc--) { 94 if (argv[1][0] != '-') 95 sys = argv[1]; 96 else switch (argv[1][1]) { 97 98 case 'v': 99 vflag++; 100 break; 101 102 case 'n': 103 noesc++; 104 break; 105 106 case '0': case '1': case '2': case '3': case '4': 107 case '5': case '6': case '7': case '8': case '9': 108 BR = atoi(&argv[1][1]); 109 break; 110 111 default: 112 fprintf(stderr, "%s: %s, unknown option\n", __progname, 113 argv[1]); 114 break; 115 } 116 } 117 118 if (sys == NOSTR) 119 goto notnumber; 120 if (isalpha(*sys)) 121 goto notnumber; 122 /* 123 * System name is really a phone number... 124 * Copy the number then stomp on the original (in case the number 125 * is private, we don't want 'ps' or 'w' to find it). 126 */ 127 if (strlen(sys) > sizeof PNbuf - 1) { 128 fprintf(stderr, "%s: phone number too long (max = %d bytes)\n", 129 __progname, (int)sizeof(PNbuf) - 1); 130 exit(1); 131 } 132 strlcpy(PNbuf, sys, sizeof PNbuf - 1); 133 for (p = sys; *p; p++) 134 *p = '\0'; 135 PN = PNbuf; 136 (void)snprintf(sbuf, sizeof(sbuf), "tip%ld", BR); 137 sys = sbuf; 138 139notnumber: 140 (void)signal(SIGINT, cleanup); 141 (void)signal(SIGQUIT, cleanup); 142 (void)signal(SIGHUP, cleanup); 143 (void)signal(SIGTERM, cleanup); 144 (void)signal(SIGCHLD, SIG_DFL); 145 146 if ((i = hunt(sys)) == 0) { 147 printf("all ports busy\n"); 148 exit(3); 149 } 150 if (i == -1) { 151 printf("link down\n"); 152 (void)uu_unlock(uucplock); 153 exit(3); 154 } 155 setbuf(stdout, NULL); 156 loginit(); 157 158 /* 159 * Now that we have the logfile and the ACU open 160 * return to the real uid and gid. These things will 161 * be closed on exit. Swap real and effective uid's 162 * so we can get the original permissions back 163 * for removing the uucp lock. 164 */ 165 user_uid(); 166 167 /* 168 * Kludge, their's no easy way to get the initialization 169 * in the right order, so force it here 170 */ 171 if ((PH = getenv("PHONES")) == NOSTR) 172 PH = _PATH_PHONES; 173 vinit(); /* init variables */ 174 setparity("none"); /* set the parity table */ 175 176 /* 177 * Hardwired connections require the 178 * line speed set before they make any transmissions 179 * (this is particularly true of things like a DF03-AC) 180 */ 181 if (HW && ttysetup(number(value(BAUDRATE)))) { 182 fprintf(stderr, "%s: bad baud rate %ld\n", __progname, 183 number(value(BAUDRATE))); 184 daemon_uid(); 185 (void)uu_unlock(uucplock); 186 exit(3); 187 } 188 if ((p = con())) { 189 printf("\07%s\n[EOT]\n", p); 190 daemon_uid(); 191 (void)uu_unlock(uucplock); 192 exit(1); 193 } 194 if (!HW && ttysetup(number(value(BAUDRATE)))) { 195 fprintf(stderr, "%s: bad baud rate %ld\n", __progname, 196 number(value(BAUDRATE))); 197 daemon_uid(); 198 (void)uu_unlock(uucplock); 199 exit(3); 200 } 201cucommon: 202 /* 203 * From here down the code is shared with 204 * the "cu" version of tip. 205 */ 206 207 i = fcntl(FD, F_GETFL); 208 if (i == -1) { 209 perror("fcntl"); 210 cleanup(0); 211 } 212 i = fcntl(FD, F_SETFL, i & ~O_NONBLOCK); 213 if (i == -1) { 214 perror("fcntl"); 215 cleanup(0); 216 } 217 218 tcgetattr(0, &defterm); 219 gotdefterm = 1; 220 term = defterm; 221 term.c_lflag &= ~(ICANON|IEXTEN|ECHO); 222 term.c_iflag &= ~(INPCK|ICRNL); 223 term.c_oflag &= ~OPOST; 224 term.c_cc[VMIN] = 1; 225 term.c_cc[VTIME] = 0; 226 defchars = term; 227 term.c_cc[VINTR] = term.c_cc[VQUIT] = term.c_cc[VSUSP] = 228 term.c_cc[VDSUSP] = term.c_cc[VDISCARD] = 229 term.c_cc[VLNEXT] = _POSIX_VDISABLE; 230 raw(); 231 232 pipe(fildes); pipe(repdes); 233 (void)signal(SIGALRM, timeout); 234 235 if (value(LINEDISC) != TTYDISC) { 236 int ld = (int)(intptr_t)value(LINEDISC); 237 ioctl(FD, TIOCSETD, &ld); 238 } 239 240 /* 241 * Everything's set up now: 242 * connection established (hardwired or dialup) 243 * line conditioned (baud rate, mode, etc.) 244 * internal data structures (variables) 245 * so, fork one process for local side and one for remote. 246 */ 247 printf(cumode ? "Connected\r\n" : "\07connected\r\n"); 248 tipin_pid = getpid(); 249 if ((tipout_pid = fork())) 250 tipin(); 251 else 252 tipout(); 253 /*NOTREACHED*/ 254 exit(0); 255} 256 257void 258cleanup(int signo) 259{ 260 daemon_uid(); 261 (void)uu_unlock(uucplock); 262 if (odisc) 263 ioctl(0, TIOCSETD, &odisc); 264 unraw(); 265 if (signo && tipout_pid) { 266 kill(tipout_pid, signo); 267 wait(NULL); 268 } 269 exit(0); 270} 271 272/* 273 * Muck with user ID's. We are setuid to the owner of the lock 274 * directory when we start. user_uid() reverses real and effective 275 * ID's after startup, to run with the user's permissions. 276 * daemon_uid() switches back to the privileged uid for unlocking. 277 * Finally, to avoid running a shell with the wrong real uid, 278 * shell_uid() sets real and effective uid's to the user's real ID. 279 */ 280static int uidswapped; 281 282void 283user_uid(void) 284{ 285 if (uidswapped == 0) { 286 seteuid(uid); 287 uidswapped = 1; 288 } 289} 290 291void 292daemon_uid(void) 293{ 294 295 if (uidswapped) { 296 seteuid(euid); 297 uidswapped = 0; 298 } 299} 300 301void 302shell_uid(void) 303{ 304 setegid(gid); 305 seteuid(uid); 306} 307 308/* 309 * put the controlling keyboard into raw mode 310 */ 311void 312raw(void) 313{ 314 tcsetattr(0, TCSADRAIN, &term); 315} 316 317 318/* 319 * return keyboard to normal mode 320 */ 321void 322unraw(void) 323{ 324 if (gotdefterm) 325 tcsetattr(0, TCSADRAIN, &defterm); 326} 327 328/* 329 * give up exclusive tty access 330 */ 331void 332unexcl() 333{ 334 ioctl(FD, TIOCNXCL, 0); 335} 336 337static jmp_buf promptbuf; 338 339/* 340 * Print string ``s'', then read a string 341 * in from the terminal. Handles signals & allows use of 342 * normal erase and kill characters. 343 */ 344int 345prompt(char *s, char *p, size_t sz) 346{ 347 int c; 348 char *b = p; 349 sig_t oint, oquit; 350 351 stoprompt = 0; 352 oint = signal(SIGINT, intprompt); 353 oquit = signal(SIGQUIT, SIG_IGN); 354 unraw(); 355 printf("%s", s); 356 if (setjmp(promptbuf) == 0) 357 while ((c = getchar()) != EOF && (*p = c) != '\n' && --sz > 0) 358 p++; 359 *p = '\0'; 360 361 raw(); 362 (void)signal(SIGINT, oint); 363 (void)signal(SIGQUIT, oquit); 364 return (stoprompt || p == b); 365} 366 367/* 368 * Interrupt service routine during prompting 369 */ 370/*ARGSUSED*/ 371static void 372intprompt(int signo) 373{ 374 (void)signal(SIGINT, SIG_IGN); 375 stoprompt = 1; 376 printf("\r\n"); 377 longjmp(promptbuf, 1); 378} 379 380/* 381 * ****TIPIN TIPIN**** 382 */ 383static void 384tipin(void) 385{ 386 int bol = 1; 387 int gch; 388 char ch; 389 390 /* 391 * Kinda klugey here... 392 * check for scripting being turned on from the .tiprc file, 393 * but be careful about just using setscript(), as we may 394 * send a SIGEMT before tipout has a chance to set up catching 395 * it; so wait a second, then setscript() 396 */ 397 if (boolean(value(SCRIPT))) { 398 sleep(1); 399 setscript(); 400 } 401 402 while (1) { 403 gch = getchar()&STRIP_PAR; 404 /* XXX does not check for EOF */ 405 if ((gch == character(value(ESCAPE))) && bol) { 406 if (!noesc) { 407 if (!(gch = escape())) 408 continue; 409 } 410 } else if (!cumode && gch == character(value(RAISECHAR))) { 411 setboolean(value(RAISE), !boolean(value(RAISE))); 412 continue; 413 } else if (gch == '\r') { 414 bol = 1; 415 ch = gch; 416 parwrite(FD, &ch, 1); 417 if (boolean(value(HALFDUPLEX))) 418 printf("\r\n"); 419 continue; 420 } else if (!cumode && gch == character(value(FORCE))) 421 gch = getchar()&STRIP_PAR; 422 bol = any(gch, value(EOL)); 423 if (boolean(value(RAISE)) && islower(gch)) 424 gch = toupper(gch); 425 ch = gch; 426 parwrite(FD, &ch, 1); 427 if (boolean(value(HALFDUPLEX))) 428 printf("%c", ch); 429 } 430} 431 432extern esctable_t etable[]; 433 434/* 435 * Escape handler -- 436 * called on recognition of ``escapec'' at the beginning of a line 437 */ 438static int 439escape(void) 440{ 441 int gch; 442 esctable_t *p; 443 char c = character(value(ESCAPE)); 444 445 gch = (getchar()&STRIP_PAR); 446 /* XXX does not check for EOF */ 447 for (p = etable; p->e_char; p++) 448 if (p->e_char == gch) { 449 if ((p->e_flags&PRIV) && uid) 450 continue; 451 printf("%s", ctrl(c)); 452 (*p->e_func)(gch); 453 return (0); 454 } 455 /* ESCAPE ESCAPE forces ESCAPE */ 456 if (c != gch) 457 parwrite(FD, &c, 1); 458 return (gch); 459} 460 461int 462any(int cc, char *p) 463{ 464 char c = cc; 465 while (p && *p) 466 if (*p++ == c) 467 return (1); 468 return (0); 469} 470 471size_t 472size(char *s) 473{ 474 size_t i = 0; 475 476 while (s && *s++) 477 i++; 478 return (i); 479} 480 481char * 482interp(char *s) 483{ 484 static char buf[256]; 485 char *p = buf, c, *q; 486 487 while ((c = *s++)) { 488 for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++) 489 if (*q++ == c) { 490 *p++ = '\\'; *p++ = *q; 491 goto next; 492 } 493 if (c < 040) { 494 *p++ = '^'; *p++ = c + 'A'-1; 495 } else if (c == 0177) { 496 *p++ = '^'; *p++ = '?'; 497 } else 498 *p++ = c; 499 next: 500 ; 501 } 502 *p = '\0'; 503 return (buf); 504} 505 506char * 507ctrl(char c) 508{ 509 static char s[3]; 510 511 if (c < 040 || c == 0177) { 512 s[0] = '^'; 513 s[1] = c == 0177 ? '?' : c+'A'-1; 514 s[2] = '\0'; 515 } else { 516 s[0] = c; 517 s[1] = '\0'; 518 } 519 return (s); 520} 521 522/* 523 * Help command 524 */ 525void 526help(int c) 527{ 528 esctable_t *p; 529 530 printf("%c\r\n", c); 531 for (p = etable; p->e_char; p++) { 532 if ((p->e_flags&PRIV) && uid) 533 continue; 534 printf("%2s", ctrl(character(value(ESCAPE)))); 535 printf("%-2s %c %s\r\n", ctrl(p->e_char), 536 p->e_flags&EXP ? '*': ' ', p->e_help); 537 } 538} 539 540/* 541 * Set up the "remote" tty's state 542 */ 543int 544ttysetup(int speed) 545{ 546 struct termios cntrl; 547 548 if (tcgetattr(FD, &cntrl)) 549 return (-1); 550 cfsetspeed(&cntrl, speed); 551 cntrl.c_cflag &= ~(CSIZE|PARENB); 552 cntrl.c_cflag |= CS8; 553 if (boolean(value(DC))) 554 cntrl.c_cflag |= CLOCAL; 555 if (boolean(value(HARDWAREFLOW))) 556 cntrl.c_cflag |= CRTSCTS; 557 cntrl.c_iflag &= ~(ISTRIP|ICRNL); 558 cntrl.c_oflag &= ~OPOST; 559 cntrl.c_lflag &= ~(ICANON|ISIG|IEXTEN|ECHO); 560 cntrl.c_cc[VMIN] = 1; 561 cntrl.c_cc[VTIME] = 0; 562 if (boolean(value(TAND))) 563 cntrl.c_iflag |= IXOFF; 564 return (tcsetattr(FD, TCSAFLUSH, &cntrl)); 565} 566 567static char partab[0200]; 568 569/* 570 * Do a write to the remote machine with the correct parity. 571 * We are doing 8 bit wide output, so we just generate a character 572 * with the right parity and output it. 573 */ 574void 575parwrite(int fd, char *buf, size_t n) 576{ 577 size_t i; 578 char *bp; 579 580 bp = buf; 581 if (bits8 == 0) 582 for (i = 0; i < n; i++) { 583 *bp = partab[(*bp) & 0177]; 584 bp++; 585 } 586 if (write(fd, buf, n) < 0) { 587 if (errno == EIO) 588 tipabort("Lost carrier."); 589 /* this is questionable */ 590 perror("write"); 591 } 592} 593 594/* 595 * Build a parity table with appropriate high-order bit. 596 */ 597void 598setparity(char *defparity) 599{ 600 int i, flip, clr, set; 601 char *parity; 602 extern const unsigned char evenpartab[]; 603 604 if (value(PARITY) == NOSTR) 605 value(PARITY) = defparity; 606 parity = value(PARITY); 607 if (equal(parity, "none")) { 608 bits8 = 1; 609 return; 610 } 611 bits8 = 0; 612 flip = 0; 613 clr = 0377; 614 set = 0; 615 if (equal(parity, "odd")) 616 flip = 0200; /* reverse bit 7 */ 617 else if (equal(parity, "zero")) 618 clr = 0177; /* turn off bit 7 */ 619 else if (equal(parity, "one")) 620 set = 0200; /* turn on bit 7 */ 621 else if (!equal(parity, "even")) { 622 (void) fprintf(stderr, "%s: unknown parity value\r\n", parity); 623 (void) fflush(stderr); 624 } 625 for (i = 0; i < 0200; i++) 626 partab[i] = ((evenpartab[i] ^ flip) | set) & clr; 627} 628