1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#) Copyright (c) 1983, 1993 The Regents of the University of California. All rights reserved. 34 * @(#)tip.c 8.1 (Berkeley) 6/6/93 35 * $FreeBSD: src/usr.bin/tip/tip/tip.c,v 1.12.2.2 2001/06/02 08:08:24 phk Exp $ 36 */ 37 38 /* 39 Forward declarations 40 */ 41 void ttysetup (int speed); 42 43 /* 44 * tip - UNIX link to other systems 45 * tip [-v] [-speed] system-name 46 * or 47 * cu phone-number [-s speed] [-l line] [-a acu] 48 */ 49 50 #include <err.h> 51 #include <errno.h> 52 #include <sys/types.h> 53 #include <libutil.h> 54 #include "tip.h" 55 #include "pathnames.h" 56 57 static void intprompt(int); 58 static void killchild(void); 59 static void tipdone(int); 60 static char *sname(char *); 61 char PNbuf[256]; /* This limits the size of a number */ 62 63 static void usage(void); 64 void setparity(char *); 65 void xpwrite(int, char *, int); 66 char escape(void); 67 void tipin(void); 68 int prompt(char *, char *, size_t); 69 void unraw(void); 70 void shell_uid(void); 71 void daemon_uid(void); 72 void user_uid(void); 73 74 int 75 main(int argc, char *argv[]) 76 { 77 char *system = NULL; 78 int i; 79 char *p; 80 char sbuf[12]; 81 82 gid = getgid(); 83 egid = getegid(); 84 uid = getuid(); 85 euid = geteuid(); 86 87 if (equal(sname(argv[0]), "cu")) { 88 cumode = 1; 89 cumain(argc, argv); 90 goto cucommon; 91 } 92 93 if (argc > 4) 94 usage(); 95 if (!isatty(0)) 96 errx(1, "must be interactive"); 97 98 for (; argc > 1; argv++, argc--) { 99 if (argv[1][0] != '-') 100 system = argv[1]; 101 else switch (argv[1][1]) { 102 103 case 'v': 104 vflag++; 105 break; 106 107 case '0': case '1': case '2': case '3': case '4': 108 case '5': case '6': case '7': case '8': case '9': 109 BR = atoi(&argv[1][1]); 110 break; 111 112 default: 113 warnx("%s, unknown option", argv[1]); 114 break; 115 } 116 } 117 118 if (system == NULL) 119 goto notnumber; 120 if (isalpha(*system)) 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(system) > sizeof(PNbuf) - 1) 128 errx(1, "phone number too long (max = %zd bytes)", sizeof PNbuf - 1); 129 strncpy(PNbuf, system, sizeof(PNbuf) - 1); 130 for (p = system; *p; p++) 131 *p = '\0'; 132 PN = PNbuf; 133 (void)snprintf(sbuf, sizeof(sbuf), "tip%ld", BR); 134 system = sbuf; 135 136 notnumber: 137 (void)signal(SIGINT, cleanup); 138 (void)signal(SIGQUIT, cleanup); 139 (void)signal(SIGHUP, cleanup); 140 (void)signal(SIGTERM, cleanup); 141 (void)signal(SIGUSR1, tipdone); 142 143 if ((i = hunt(system)) == 0) { 144 printf("all ports busy\n"); 145 exit(3); 146 } 147 if (i == -1) { 148 printf("link down\n"); 149 (void)uu_unlock(uucplock); 150 exit(3); 151 } 152 setbuf(stdout, NULL); 153 loginit(); 154 155 /* 156 * Kludge, their's no easy way to get the initialization 157 * in the right order, so force it here 158 */ 159 if ((PH = getenv("PHONES")) == NULL) 160 PH = _PATH_PHONES; 161 vinit(); /* init variables */ 162 setparity("even"); /* set the parity table */ 163 if ((i = speed(number(value(BAUDRATE)))) == 0) { 164 printf("tip: bad baud rate %d\n", number(value(BAUDRATE))); 165 (void)uu_unlock(uucplock); 166 exit(3); 167 } 168 169 /* 170 * Now that we have the logfile and the ACU open 171 * return to the real uid and gid. These things will 172 * be closed on exit. Swap real and effective uid's 173 * so we can get the original permissions back 174 * for removing the uucp lock. 175 */ 176 user_uid(); 177 178 /* 179 * Hardwired connections require the 180 * line speed set before they make any transmissions 181 * (this is particularly true of things like a DF03-AC) 182 */ 183 if (HW) 184 ttysetup(i); 185 if ((p = connect())) { 186 printf("\07%s\n[EOT]\n", p); 187 daemon_uid(); 188 (void)uu_unlock(uucplock); 189 exit(1); 190 } 191 if (!HW) 192 ttysetup(i); 193 cucommon: 194 /* 195 * From here down the code is shared with 196 * the "cu" version of tip. 197 */ 198 199 tcgetattr (0, &otermios); 200 ctermios = otermios; 201 ctermios.c_iflag = (IMAXBEL|IXANY|ISTRIP|IXON|BRKINT); 202 ctermios.c_lflag = (PENDIN|IEXTEN|ISIG|ECHOCTL|ECHOE|ECHOKE); 203 ctermios.c_cflag = (CLOCAL|HUPCL|CREAD|CS8); 204 ctermios.c_cc[VINTR] = ctermios.c_cc[VQUIT] = -1; 205 ctermios.c_cc[VSUSP] = ctermios.c_cc[VDSUSP] = ctermios.c_cc[VDISCARD] = 206 ctermios.c_cc[VLNEXT] = -1; 207 raw(); 208 209 pipe(fildes); pipe(repdes); 210 (void)signal(SIGALRM, timeoutfunc); 211 212 /* 213 * Everything's set up now: 214 * connection established (hardwired or dialup) 215 * line conditioned (baud rate, mode, etc.) 216 * internal data structures (variables) 217 * so, fork one process for local side and one for remote. 218 */ 219 printf(cumode ? "Connected\r\n" : "\07connected\r\n"); 220 221 if (LI != NULL && tiplink (LI, 0) != 0) { 222 tipabort ("login failed"); 223 } 224 225 if ((pid = fork())) 226 tipin(); 227 else 228 tipout(); 229 /*NOTREACHED*/ 230 } 231 232 static void 233 usage(void) 234 { 235 fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n"); 236 exit(1); 237 } 238 239 void 240 killchild(void) 241 { 242 if (pid != 0) { 243 kill(pid, SIGTERM); 244 pid = 0; 245 } 246 } 247 248 void 249 cleanup(int signo) 250 { 251 252 daemon_uid(); 253 (void)uu_unlock(uucplock); 254 exit(0); 255 } 256 257 void 258 tipdone(int signo) 259 { 260 tipabort("Hangup."); 261 } 262 /* 263 * Muck with user ID's. We are setuid to the owner of the lock 264 * directory when we start. user_uid() reverses real and effective 265 * ID's after startup, to run with the user's permissions. 266 * daemon_uid() switches back to the privileged uid for unlocking. 267 * Finally, to avoid running a shell with the wrong real uid, 268 * shell_uid() sets real and effective uid's to the user's real ID. 269 */ 270 static int uidswapped; 271 272 void 273 user_uid(void) 274 { 275 if (uidswapped == 0) { 276 seteuid(uid); 277 uidswapped = 1; 278 } 279 } 280 281 void 282 daemon_uid(void) 283 { 284 if (uidswapped) { 285 seteuid(euid); 286 uidswapped = 0; 287 } 288 } 289 290 void 291 shell_uid(void) 292 { 293 setegid(gid); 294 seteuid(uid); 295 } 296 297 /* 298 * put the controlling keyboard into raw mode 299 */ 300 void 301 raw(void) 302 { 303 tcsetattr (0, TCSANOW, &ctermios); 304 } 305 306 307 /* 308 * return keyboard to normal mode 309 */ 310 void 311 unraw(void) 312 { 313 tcsetattr (0, TCSANOW, &otermios); 314 } 315 316 static jmp_buf promptbuf; 317 318 /* 319 * Print string ``s'', then read a string 320 * in from the terminal. Handles signals & allows use of 321 * normal erase and kill characters. 322 */ 323 int 324 prompt(char *s, char *p, size_t sz) 325 { 326 char *b = p; 327 sig_t oint, oquit; 328 329 stoprompt = 0; 330 oint = signal(SIGINT, intprompt); 331 oquit = signal(SIGQUIT, SIG_IGN); 332 unraw(); 333 printf("%s", s); 334 if (setjmp(promptbuf) == 0) 335 while ((*p = getchar()) != EOF && *p != '\n' && --sz > 0) 336 p++; 337 *p = '\0'; 338 339 raw(); 340 (void)signal(SIGINT, oint); 341 (void)signal(SIGQUIT, oquit); 342 return (stoprompt || p == b); 343 } 344 345 /* 346 * Interrupt service routine during prompting 347 */ 348 void 349 intprompt(int signo) 350 { 351 352 (void)signal(SIGINT, SIG_IGN); 353 stoprompt = 1; 354 printf("\r\n"); 355 longjmp(promptbuf, 1); 356 } 357 358 /* 359 * ****TIPIN TIPIN**** 360 */ 361 void 362 tipin(void) 363 { 364 int i; 365 char gch, bol = 1; 366 367 atexit(killchild); 368 369 /* 370 * Kinda klugey here... 371 * check for scripting being turned on from the .tiprc file, 372 * but be careful about just using setscript(), as we may 373 * send a SIGEMT before tipout has a chance to set up catching 374 * it; so wait a second, then setscript() 375 */ 376 if (boolean(value(SCRIPT))) { 377 sleep(1); 378 setscript(); 379 } 380 381 while (1) { 382 i = getchar(); 383 if (i == EOF) 384 break; 385 gch = i&0177; 386 if ((gch == character(value(ESCAPE))) && bol) { 387 if (!(gch = escape())) 388 continue; 389 } else if (!cumode && gch == character(value(RAISECHAR))) { 390 boolean(value(RAISE)) = !boolean(value(RAISE)); 391 continue; 392 } else if (gch == '\r') { 393 bol = 1; 394 xpwrite(FD, &gch, 1); 395 if (boolean(value(HALFDUPLEX))) 396 printf("\r\n"); 397 continue; 398 } else if (!cumode && gch == character(value(FORCE))) { 399 i = getchar(); 400 if (i == EOF) 401 break; 402 gch = i & 0177; 403 } 404 bol = any(gch, value(EOL)); 405 if (boolean(value(RAISE)) && islower(gch)) 406 gch = toupper(gch); 407 xpwrite(FD, &gch, 1); 408 if (boolean(value(HALFDUPLEX))) 409 printf("%c", gch); 410 } 411 } 412 413 extern esctable_t etable[]; 414 415 /* 416 * Escape handler -- 417 * called on recognition of ``escapec'' at the beginning of a line 418 */ 419 char 420 escape(void) 421 { 422 char gch; 423 esctable_t *p; 424 char c = character(value(ESCAPE)); 425 int i; 426 427 i = getchar(); 428 if (i == EOF) 429 return 0; 430 gch = (i&0177); 431 for (p = etable; p->e_char; p++) 432 if (p->e_char == gch) { 433 if ((p->e_flags&PRIV) && uid) 434 continue; 435 printf("%s", ctrl(c)); 436 (*p->e_func)(gch); 437 return (0); 438 } 439 /* ESCAPE ESCAPE forces ESCAPE */ 440 if (c != gch) 441 xpwrite(FD, &c, 1); 442 return (gch); 443 } 444 445 int 446 speed(int n) 447 { 448 return (n); 449 } 450 451 int 452 any(char c, char *p) 453 { 454 while (p && *p) 455 if (*p++ == c) 456 return (1); 457 return (0); 458 } 459 460 int 461 size(char *s) 462 { 463 int i = 0; 464 465 while (s && *s++) 466 i++; 467 return (i); 468 } 469 470 char * 471 interp(char *s) 472 { 473 static char buf[256]; 474 char *p = buf, c, *q; 475 476 while ((c = *s++)) { 477 for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++) 478 if (*q++ == c) { 479 *p++ = '\\'; *p++ = *q; 480 goto next; 481 } 482 if (c < 040) { 483 *p++ = '^'; *p++ = c + 'A'-1; 484 } else if (c == 0177) { 485 *p++ = '^'; *p++ = '?'; 486 } else 487 *p++ = c; 488 next: 489 ; 490 } 491 *p = '\0'; 492 return (buf); 493 } 494 495 char * 496 ctrl(char c) 497 { 498 static char s[3]; 499 500 if (c < 040 || c == 0177) { 501 s[0] = '^'; 502 s[1] = c == 0177 ? '?' : c+'A'-1; 503 s[2] = '\0'; 504 } else { 505 s[0] = c; 506 s[1] = '\0'; 507 } 508 return (s); 509 } 510 511 /* 512 * Help command 513 */ 514 void 515 help(int c) 516 { 517 esctable_t *p; 518 519 printf("%c\r\n", c); 520 for (p = etable; p->e_char; p++) { 521 if ((p->e_flags&PRIV) && uid) 522 continue; 523 printf("%2s", ctrl(character(value(ESCAPE)))); 524 printf("%-2s %c %s\r\n", ctrl(p->e_char), 525 (p->e_flags&EXP) ? '*': ' ', p->e_help); 526 } 527 } 528 529 /* 530 * Set up the "remote" tty's state 531 */ 532 void 533 ttysetup (int speed) 534 { 535 struct termios termios; 536 tcgetattr (FD, &termios); 537 if (boolean(value(TAND))) 538 termios.c_iflag = IXOFF; 539 else 540 termios.c_iflag = 0; 541 termios.c_lflag = (PENDIN|ECHOKE|ECHOE); 542 termios.c_cflag = (CLOCAL|HUPCL|CREAD|CS8); 543 termios.c_ispeed = termios.c_ospeed = speed; 544 tcsetattr (FD, TCSANOW, &termios); 545 } 546 547 /* 548 * Return "simple" name from a file name, 549 * strip leading directories. 550 */ 551 char * 552 sname(char *s) 553 { 554 char *p = s; 555 556 while (*s) 557 if (*s++ == '/') 558 p = s; 559 return (p); 560 } 561 562 static char partab[0200]; 563 static int bits8; 564 565 /* 566 * Do a write to the remote machine with the correct parity. 567 * We are doing 8 bit wide output, so we just generate a character 568 * with the right parity and output it. 569 */ 570 void 571 xpwrite(int fd, char *buf, int n) 572 { 573 int i; 574 char *bp; 575 576 bp = buf; 577 if (bits8 == 0) 578 for (i = 0; i < n; i++) { 579 *bp = partab[(*bp) & 0177]; 580 bp++; 581 } 582 if (write(fd, buf, n) < 0) { 583 if (errno == EIO) 584 tipabort("Lost carrier."); 585 if (errno == ENODEV) 586 tipabort("tty not available."); 587 tipabort("Something wrong..."); 588 } 589 } 590 591 /* 592 * Build a parity table with appropriate high-order bit. 593 */ 594 void 595 setparity(char *defparity) 596 { 597 int i, flip, clr, set; 598 char *parity; 599 extern char evenpartab[]; 600 601 if (value(PARITY) == NULL) 602 value(PARITY) = defparity; 603 parity = value(PARITY); 604 if (equal(parity, "none")) { 605 bits8 = 1; 606 return; 607 } 608 bits8 = 0; 609 flip = 0; 610 clr = 0377; 611 set = 0; 612 if (equal(parity, "odd")) 613 flip = 0200; /* reverse bit 7 */ 614 else if (equal(parity, "zero")) 615 clr = 0177; /* turn off bit 7 */ 616 else if (equal(parity, "one")) 617 set = 0200; /* turn on bit 7 */ 618 else if (!equal(parity, "even")) { 619 (void) fprintf(stderr, "%s: unknown parity value\r\n", parity); 620 (void) fflush(stderr); 621 } 622 for (i = 0; i < 0200; i++) 623 partab[i] = (evenpartab[i] ^ flip) | (set & clr); 624 } 625