1/* vi: set sw=4 ts=4: */ 2/* agetty.c - another getty program for Linux. By W. Z. Venema 1989 3 * Ported to Linux by Peter Orbaek <poe@daimi.aau.dk> 4 * This program is freely distributable. The entire man-page used to 5 * be here. Now read the real man-page agetty.8 instead. 6 * 7 * option added by Eric Rasmussen <ear@usfirst.org> - 12/28/95 8 * 9 * 1999-02-22 Arkadiusz Mi�kiewicz <misiek@misiek.eu.org> 10 * - added Native Language Support 11 12 * 1999-05-05 Thorsten Kranzkowski <dl8bcu@gmx.net> 13 * - enable hardware flow control before displaying /etc/issue 14 * 15 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. 16 * 17 */ 18 19#include "libbb.h" 20#include <syslog.h> 21 22#if ENABLE_FEATURE_UTMP 23#include <utmp.h> 24#endif 25 26/* 27 * Some heuristics to find out what environment we are in: if it is not 28 * System V, assume it is SunOS 4. 29 */ 30#ifdef LOGIN_PROCESS /* defined in System V utmp.h */ 31#define SYSV_STYLE /* select System V style getty */ 32#include <sys/utsname.h> 33#include <time.h> 34#if ENABLE_FEATURE_WTMP 35extern void updwtmp(const char *filename, const struct utmp *ut); 36static void update_utmp(const char *line); 37#endif 38#endif /* LOGIN_PROCESS */ 39 40/* 41 * Things you may want to modify. 42 * 43 * You may disagree with the default line-editing etc. characters defined 44 * below. Note, however, that DEL cannot be used for interrupt generation 45 * and for line editing at the same time. 46 */ 47 48/* I doubt there are systems which still need this */ 49#undef HANDLE_ALLCAPS 50 51#define _PATH_LOGIN "/bin/login" 52 53/* If ISSUE is not defined, getty will never display the contents of the 54 * /etc/issue file. You will not want to spit out large "issue" files at the 55 * wrong baud rate. 56 */ 57#define ISSUE "/etc/issue" /* displayed before the login prompt */ 58 59/* Some shorthands for control characters. */ 60#define CTL(x) (x ^ 0100) /* Assumes ASCII dialect */ 61#define CR CTL('M') /* carriage return */ 62#define NL CTL('J') /* line feed */ 63#define BS CTL('H') /* back space */ 64#define DEL CTL('?') /* delete */ 65 66/* Defaults for line-editing etc. characters; you may want to change this. */ 67#define DEF_ERASE DEL /* default erase character */ 68#define DEF_INTR CTL('C') /* default interrupt character */ 69#define DEF_QUIT CTL('\\') /* default quit char */ 70#define DEF_KILL CTL('U') /* default kill char */ 71#define DEF_EOF CTL('D') /* default EOF char */ 72#define DEF_EOL '\n' 73#define DEF_SWITCH 0 /* default switch char */ 74 75/* 76 * When multiple baud rates are specified on the command line, the first one 77 * we will try is the first one specified. 78 */ 79#define FIRST_SPEED 0 80 81/* Storage for command-line options. */ 82 83#define MAX_SPEED 10 /* max. nr. of baud rates */ 84 85struct options { 86 int flags; /* toggle switches, see below */ 87 unsigned timeout; /* time-out period */ 88 const char *login; /* login program */ 89 const char *tty; /* name of tty */ 90 const char *initstring; /* modem init string */ 91 const char *issue; /* alternative issue file */ 92 int numspeed; /* number of baud rates to try */ 93 int speeds[MAX_SPEED]; /* baud rates to be tried */ 94}; 95 96static const char opt_string[] ALIGN1 = "I:LH:f:hil:mt:wn"; 97#define F_INITSTRING (1<<0) /* initstring is set */ 98#define F_LOCAL (1<<1) /* force local */ 99#define F_FAKEHOST (1<<2) /* force fakehost */ 100#define F_CUSTISSUE (1<<3) /* give alternative issue file */ 101#define F_RTSCTS (1<<4) /* enable RTS/CTS flow control */ 102#define F_ISSUE (1<<5) /* display /etc/issue */ 103#define F_LOGIN (1<<6) /* non-default login program */ 104#define F_PARSE (1<<7) /* process modem status messages */ 105#define F_TIMEOUT (1<<8) /* time out */ 106#define F_WAITCRLF (1<<9) /* wait for CR or LF */ 107#define F_NOPROMPT (1<<10) /* don't ask for login name! */ 108 109/* Storage for things detected while the login name was read. */ 110struct chardata { 111 unsigned char erase; /* erase character */ 112 unsigned char kill; /* kill character */ 113 unsigned char eol; /* end-of-line character */ 114 unsigned char parity; /* what parity did we see */ 115#ifdef HANDLE_ALLCAPS 116 unsigned char capslock; /* upper case without lower case */ 117#endif 118}; 119 120/* Initial values for the above. */ 121static const struct chardata init_chardata = { 122 DEF_ERASE, /* default erase character */ 123 DEF_KILL, /* default kill character */ 124 13, /* default eol char */ 125 0, /* space parity */ 126#ifdef HANDLE_ALLCAPS 127 0, /* no capslock */ 128#endif 129}; 130 131/* The following is used for understandable diagnostics. */ 132 133/* Fake hostname for ut_host specified on command line. */ 134static char *fakehost = NULL; 135 136/* ... */ 137#ifdef DEBUGGING 138#define debug(s) fprintf(dbf,s); fflush(dbf) 139#define DEBUGTERM "/dev/ttyp0" 140static FILE *dbf; 141#else 142#define debug(s) /* nothing */ 143#endif 144 145 146/* bcode - convert speed string to speed code; return 0 on failure */ 147static int bcode(const char *s) 148{ 149 int r; 150 unsigned value = bb_strtou(s, NULL, 10); 151 if (errno) { 152 return -1; 153 } 154 r = tty_value_to_baud(value); 155 if (r > 0) { 156 return r; 157 } 158 return 0; 159} 160 161 162/* parse_speeds - parse alternate baud rates */ 163static void parse_speeds(struct options *op, char *arg) 164{ 165 char *cp; 166 167 debug("entered parse_speeds\n"); 168 for (cp = strtok(arg, ","); cp != 0; cp = strtok((char *) 0, ",")) { 169 if ((op->speeds[op->numspeed++] = bcode(cp)) <= 0) 170 bb_error_msg_and_die("bad speed: %s", cp); 171 if (op->numspeed > MAX_SPEED) 172 bb_error_msg_and_die("too many alternate speeds"); 173 } 174 debug("exiting parsespeeds\n"); 175} 176 177 178/* parse_args - parse command-line arguments */ 179static void parse_args(int argc, char **argv, struct options *op) 180{ 181 char *ts; 182 183 op->flags = getopt32(argv, opt_string, 184 &(op->initstring), &fakehost, &(op->issue), 185 &(op->login), &ts); 186 if (op->flags & F_INITSTRING) { 187 const char *p = op->initstring; 188 char *q; 189 190 op->initstring = q = xstrdup(op->initstring); 191 /* copy optarg into op->initstring decoding \ddd 192 octal codes into chars */ 193 while (*p) { 194 if (*p == '\\') { 195 p++; 196 *q++ = bb_process_escape_sequence(&p); 197 } else { 198 *q++ = *p++; 199 } 200 } 201 *q = '\0'; 202 } 203 op->flags ^= F_ISSUE; /* revert flag show /etc/issue */ 204 if (op->flags & F_TIMEOUT) { 205 op->timeout = xatoul_range(ts, 1, INT_MAX); 206 } 207 argv += optind; 208 argc -= optind; 209 debug("after getopt loop\n"); 210 if (argc < 2) /* check parameter count */ 211 bb_show_usage(); 212 213 /* we loosen up a bit and accept both "baudrate tty" and "tty baudrate" */ 214 if (isdigit(argv[0][0])) { 215 /* a number first, assume it's a speed (BSD style) */ 216 parse_speeds(op, argv[0]); /* baud rate(s) */ 217 op->tty = argv[1]; /* tty name */ 218 } else { 219 op->tty = argv[0]; /* tty name */ 220 parse_speeds(op, argv[1]); /* baud rate(s) */ 221 } 222 223 if (argv[2]) 224 setenv("TERM", argv[2], 1); 225 226 debug("exiting parseargs\n"); 227} 228 229/* open_tty - set up tty as standard { input, output, error } */ 230static void open_tty(const char *tty, struct termios *tp, int local) 231{ 232 int chdir_to_root = 0; 233 234 /* Set up new standard input, unless we are given an already opened port. */ 235 if (NOT_LONE_DASH(tty)) { 236 struct stat st; 237 int fd; 238 239 /* Sanity checks... */ 240 xchdir("/dev"); 241 chdir_to_root = 1; 242 xstat(tty, &st); 243 if ((st.st_mode & S_IFMT) != S_IFCHR) 244 bb_error_msg_and_die("%s: not a character device", tty); 245 246 /* Open the tty as standard input. */ 247 debug("open(2)\n"); 248 fd = xopen(tty, O_RDWR | O_NONBLOCK); 249 xdup2(fd, 0); 250 while (fd > 2) 251 close(fd--); 252 } else { 253 /* 254 * Standard input should already be connected to an open port. Make 255 * sure it is open for read/write. 256 */ 257 if ((fcntl(0, F_GETFL) & O_RDWR) != O_RDWR) 258 bb_error_msg_and_die("stdin is not open for read/write"); 259 } 260 261 /* Replace current standard output/error fd's with new ones */ 262 debug("duping\n"); 263 xdup2(0, 1); 264 xdup2(0, 2); 265 266 /* 267 * The following ioctl will fail if stdin is not a tty, but also when 268 * there is noise on the modem control lines. In the latter case, the 269 * common course of action is (1) fix your cables (2) give the modem more 270 * time to properly reset after hanging up. SunOS users can achieve (2) 271 * by patching the SunOS kernel variable "zsadtrlow" to a larger value; 272 * 5 seconds seems to be a good value. 273 */ 274 ioctl_or_perror_and_die(0, TCGETS, tp, "%s: TCGETS", tty); 275 276 /* 277 * It seems to be a terminal. Set proper protections and ownership. Mode 278 * 0622 is suitable for SYSV <4 because /bin/login does not change 279 * protections. SunOS 4 login will change the protections to 0620 (write 280 * access for group tty) after the login has succeeded. 281 */ 282 283#ifdef DEBIAN 284#warning Debian /dev/vcs[a]NN hack is deprecated and will be removed 285 { 286 /* tty to root.dialout 660 */ 287 struct group *gr; 288 int id; 289 290 gr = getgrnam("dialout"); 291 id = gr ? gr->gr_gid : 0; 292 chown(tty, 0, id); 293 chmod(tty, 0660); 294 295 /* vcs,vcsa to root.sys 600 */ 296 if (!strncmp(tty, "tty", 3) && isdigit(tty[3])) { 297 char *vcs, *vcsa; 298 299 vcs = xstrdup(tty); 300 vcsa = xmalloc(strlen(tty) + 2); 301 strcpy(vcs, "vcs"); 302 strcpy(vcs + 3, tty + 3); 303 strcpy(vcsa, "vcsa"); 304 strcpy(vcsa + 4, tty + 3); 305 306 gr = getgrnam("sys"); 307 id = gr ? gr->gr_gid : 0; 308 chown(vcs, 0, id); 309 chmod(vcs, 0600); 310 chown(vcsa, 0, id); 311 chmod(vcs, 0600); 312 313 free(vcs); 314 free(vcsa); 315 } 316 } 317#else 318 if (NOT_LONE_DASH(tty)) { 319 chown(tty, 0, 0); /* 0:0 */ 320 chmod(tty, 0622); /* crw--w--w- */ 321 } 322#endif 323 if (chdir_to_root) 324 xchdir("/"); 325} 326 327/* termios_init - initialize termios settings */ 328static void termios_init(struct termios *tp, int speed, struct options *op) 329{ 330 /* 331 * Initial termios settings: 8-bit characters, raw-mode, blocking i/o. 332 * Special characters are set after we have read the login name; all 333 * reads will be done in raw mode anyway. Errors will be dealt with 334 * later on. 335 */ 336#ifdef __linux__ 337 /* flush input and output queues, important for modems! */ 338 ioctl(0, TCFLSH, TCIOFLUSH); 339#endif 340 341 tp->c_cflag = CS8 | HUPCL | CREAD | speed; 342 if (op->flags & F_LOCAL) { 343 tp->c_cflag |= CLOCAL; 344 } 345 346 tp->c_iflag = tp->c_lflag = tp->c_line = 0; 347 tp->c_oflag = OPOST | ONLCR; 348 tp->c_cc[VMIN] = 1; 349 tp->c_cc[VTIME] = 0; 350 351 /* Optionally enable hardware flow control */ 352 353#ifdef CRTSCTS 354 if (op->flags & F_RTSCTS) 355 tp->c_cflag |= CRTSCTS; 356#endif 357 358 ioctl(0, TCSETS, tp); 359 360 /* go to blocking input even in local mode */ 361 ndelay_off(0); 362 363 debug("term_io 2\n"); 364} 365 366/* auto_baud - extract baud rate from modem status message */ 367static void auto_baud(char *buf, unsigned size_buf, struct termios *tp) 368{ 369 int speed; 370 int vmin; 371 unsigned iflag; 372 char *bp; 373 int nread; 374 375 /* 376 * This works only if the modem produces its status code AFTER raising 377 * the DCD line, and if the computer is fast enough to set the proper 378 * baud rate before the message has gone by. We expect a message of the 379 * following format: 380 * 381 * <junk><number><junk> 382 * 383 * The number is interpreted as the baud rate of the incoming call. If the 384 * modem does not tell us the baud rate within one second, we will keep 385 * using the current baud rate. It is advisable to enable BREAK 386 * processing (comma-separated list of baud rates) if the processing of 387 * modem status messages is enabled. 388 */ 389 390 /* 391 * Use 7-bit characters, don't block if input queue is empty. Errors will 392 * be dealt with later on. 393 */ 394 395 iflag = tp->c_iflag; 396 tp->c_iflag |= ISTRIP; /* enable 8th-bit stripping */ 397 vmin = tp->c_cc[VMIN]; 398 tp->c_cc[VMIN] = 0; /* don't block if queue empty */ 399 ioctl(0, TCSETS, tp); 400 401 /* 402 * Wait for a while, then read everything the modem has said so far and 403 * try to extract the speed of the dial-in call. 404 */ 405 406 sleep(1); 407 nread = read(0, buf, size_buf - 1); 408 if (nread > 0) { 409 buf[nread] = '\0'; 410 for (bp = buf; bp < buf + nread; bp++) { 411 if (isascii(*bp) && isdigit(*bp)) { 412 speed = bcode(bp); 413 if (speed) { 414 tp->c_cflag &= ~CBAUD; 415 tp->c_cflag |= speed; 416 } 417 break; 418 } 419 } 420 } 421 /* Restore terminal settings. Errors will be dealt with later on. */ 422 423 tp->c_iflag = iflag; 424 tp->c_cc[VMIN] = vmin; 425 ioctl(0, TCSETS, tp); 426} 427 428/* next_speed - select next baud rate */ 429static void next_speed(struct termios *tp, struct options *op) 430{ 431 static int baud_index = FIRST_SPEED; /* current speed index */ 432 433 baud_index = (baud_index + 1) % op->numspeed; 434 tp->c_cflag &= ~CBAUD; 435 tp->c_cflag |= op->speeds[baud_index]; 436 ioctl(0, TCSETS, tp); 437} 438 439 440/* do_prompt - show login prompt, optionally preceded by /etc/issue contents */ 441static void do_prompt(struct options *op, struct termios *tp) 442{ 443#ifdef ISSUE 444 print_login_issue(op->issue, op->tty); 445#endif 446 print_login_prompt(); 447} 448 449#ifdef HANDLE_ALLCAPS 450/* caps_lock - string contains upper case without lower case */ 451/* returns 1 if true, 0 if false */ 452static int caps_lock(const char *s) 453{ 454 while (*s) 455 if (islower(*s++)) 456 return 0; 457 return 1; 458} 459#endif 460 461/* get_logname - get user name, establish parity, speed, erase, kill, eol */ 462/* return NULL on failure, logname on success */ 463static char *get_logname(char *logname, unsigned size_logname, 464 struct options *op, struct chardata *cp, struct termios *tp) 465{ 466 char *bp; 467 char c; /* input character, full eight bits */ 468 char ascval; /* low 7 bits of input character */ 469 int bits; /* # of "1" bits per character */ 470 int mask; /* mask with 1 bit up */ 471 static const char erase[][3] = { /* backspace-space-backspace */ 472 "\010\040\010", /* space parity */ 473 "\010\040\010", /* odd parity */ 474 "\210\240\210", /* even parity */ 475 "\210\240\210", /* no parity */ 476 }; 477 478 /* Initialize kill, erase, parity etc. (also after switching speeds). */ 479 480 *cp = init_chardata; 481 482 /* Flush pending input (esp. after parsing or switching the baud rate). */ 483 484 sleep(1); 485 ioctl(0, TCFLSH, TCIFLUSH); 486 487 /* Prompt for and read a login name. */ 488 489 logname[0] = '\0'; 490 while (!logname[0]) { 491 492 /* Write issue file and prompt, with "parity" bit == 0. */ 493 494 do_prompt(op, tp); 495 496 /* Read name, watch for break, parity, erase, kill, end-of-line. */ 497 498 bp = logname; 499 cp->eol = '\0'; 500 while (cp->eol == '\0') { 501 502 /* Do not report trivial EINTR/EIO errors. */ 503 if (read(0, &c, 1) < 1) { 504 if (errno == EINTR || errno == EIO) 505 exit(0); 506 bb_perror_msg_and_die("%s: read", op->tty); 507 } 508 509 /* Do BREAK handling elsewhere. */ 510 if (c == '\0' && op->numspeed > 1) 511 return NULL; 512 513 /* Do parity bit handling. */ 514 ascval = c & 0177; 515 if (c != ascval) { /* "parity" bit on ? */ 516 bits = 1; 517 mask = 1; 518 while (mask & 0177) { 519 if (mask & ascval) 520 bits++; /* count "1" bits */ 521 mask <<= 1; 522 } 523 /* ... |= 2 - even, 1 - odd */ 524 cp->parity |= 2 - (bits & 1); 525 } 526 527 /* Do erase, kill and end-of-line processing. */ 528 switch (ascval) { 529 case CR: 530 case NL: 531 *bp = '\0'; /* terminate logname */ 532 cp->eol = ascval; /* set end-of-line char */ 533 break; 534 case BS: 535 case DEL: 536 case '#': 537 cp->erase = ascval; /* set erase character */ 538 if (bp > logname) { 539 write(1, erase[cp->parity], 3); 540 bp--; 541 } 542 break; 543 case CTL('U'): 544 case '@': 545 cp->kill = ascval; /* set kill character */ 546 while (bp > logname) { 547 write(1, erase[cp->parity], 3); 548 bp--; 549 } 550 break; 551 case CTL('D'): 552 exit(0); 553 default: 554 if (!isascii(ascval) || !isprint(ascval)) { 555 /* ignore garbage characters */ 556 } else if (bp - logname >= size_logname - 1) { 557 bb_error_msg_and_die("%s: input overrun", op->tty); 558 } else { 559 write(1, &c, 1); /* echo the character */ 560 *bp++ = ascval; /* and store it */ 561 } 562 break; 563 } 564 } 565 } 566 /* Handle names with upper case and no lower case. */ 567 568#ifdef HANDLE_ALLCAPS 569 cp->capslock = caps_lock(logname); 570 if (cp->capslock) { 571 for (bp = logname; *bp; bp++) 572 if (isupper(*bp)) 573 *bp = tolower(*bp); /* map name to lower case */ 574 } 575#endif 576 return logname; 577} 578 579/* termios_final - set the final tty mode bits */ 580static void termios_final(struct options *op, struct termios *tp, struct chardata *cp) 581{ 582 /* General terminal-independent stuff. */ 583 584 tp->c_iflag |= IXON | IXOFF; /* 2-way flow control */ 585 tp->c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE; 586 /* no longer| ECHOCTL | ECHOPRT */ 587 tp->c_oflag |= OPOST; 588 /* tp->c_cflag = 0; */ 589 tp->c_cc[VINTR] = DEF_INTR; /* default interrupt */ 590 tp->c_cc[VQUIT] = DEF_QUIT; /* default quit */ 591 tp->c_cc[VEOF] = DEF_EOF; /* default EOF character */ 592 tp->c_cc[VEOL] = DEF_EOL; 593 tp->c_cc[VSWTC] = DEF_SWITCH; /* default switch character */ 594 595 /* Account for special characters seen in input. */ 596 597 if (cp->eol == CR) { 598 tp->c_iflag |= ICRNL; /* map CR in input to NL */ 599 tp->c_oflag |= ONLCR; /* map NL in output to CR-NL */ 600 } 601 tp->c_cc[VERASE] = cp->erase; /* set erase character */ 602 tp->c_cc[VKILL] = cp->kill; /* set kill character */ 603 604 /* Account for the presence or absence of parity bits in input. */ 605 606 switch (cp->parity) { 607 case 0: /* space (always 0) parity */ 608 break; 609 case 1: /* odd parity */ 610 tp->c_cflag |= PARODD; 611 /* FALLTHROUGH */ 612 case 2: /* even parity */ 613 tp->c_cflag |= PARENB; 614 tp->c_iflag |= INPCK | ISTRIP; 615 /* FALLTHROUGH */ 616 case (1 | 2): /* no parity bit */ 617 tp->c_cflag &= ~CSIZE; 618 tp->c_cflag |= CS7; 619 break; 620 } 621 622 /* Account for upper case without lower case. */ 623#ifdef HANDLE_ALLCAPS 624 if (cp->capslock) { 625 tp->c_iflag |= IUCLC; 626 tp->c_lflag |= XCASE; 627 tp->c_oflag |= OLCUC; 628 } 629#endif 630 /* Optionally enable hardware flow control */ 631 632#ifdef CRTSCTS 633 if (op->flags & F_RTSCTS) 634 tp->c_cflag |= CRTSCTS; 635#endif 636 637 /* Finally, make the new settings effective */ 638 639 ioctl_or_perror_and_die(0, TCSETS, tp, "%s: TCSETS", op->tty); 640} 641 642 643#ifdef SYSV_STYLE 644#if ENABLE_FEATURE_UTMP 645/* update_utmp - update our utmp entry */ 646static void update_utmp(const char *line) 647{ 648 struct utmp ut; 649 struct utmp *utp; 650 time_t t; 651 int mypid = getpid(); 652 653 /* 654 * The utmp file holds miscellaneous information about things started by 655 * /sbin/init and other system-related events. Our purpose is to update 656 * the utmp entry for the current process, in particular the process type 657 * and the tty line we are listening to. Return successfully only if the 658 * utmp file can be opened for update, and if we are able to find our 659 * entry in the utmp file. 660 */ 661 if (access(_PATH_UTMP, R_OK|W_OK) == -1) { 662 close(creat(_PATH_UTMP, 0664)); 663 } 664 utmpname(_PATH_UTMP); 665 setutent(); 666 while ((utp = getutent()) 667 && !(utp->ut_type == INIT_PROCESS && utp->ut_pid == mypid)) 668 /* nothing */; 669 670 if (utp) { 671 memcpy(&ut, utp, sizeof(ut)); 672 } else { 673 /* some inits don't initialize utmp... */ 674 memset(&ut, 0, sizeof(ut)); 675 safe_strncpy(ut.ut_id, line + 3, sizeof(ut.ut_id)); 676 } 677 /* endutent(); */ 678 679 strcpy(ut.ut_user, "LOGIN"); 680 safe_strncpy(ut.ut_line, line, sizeof(ut.ut_line)); 681 if (fakehost) 682 safe_strncpy(ut.ut_host, fakehost, sizeof(ut.ut_host)); 683 time(&t); 684 ut.ut_time = t; 685 ut.ut_type = LOGIN_PROCESS; 686 ut.ut_pid = mypid; 687 688 pututline(&ut); 689 endutent(); 690 691#if ENABLE_FEATURE_WTMP 692 if (access(bb_path_wtmp_file, R_OK|W_OK) == -1) 693 close(creat(bb_path_wtmp_file, 0664)); 694 updwtmp(bb_path_wtmp_file, &ut); 695#endif 696} 697 698#endif /* CONFIG_FEATURE_UTMP */ 699#endif /* SYSV_STYLE */ 700 701 702int getty_main(int argc, char **argv); 703int getty_main(int argc, char **argv) 704{ 705 int nullfd; 706 char *logname = NULL; /* login name, given to /bin/login */ 707 /* Merging these into "struct local" may _seem_ to reduce 708 * parameter passing, but today's gcc will inline 709 * statics which are called once anyway, so don't do that */ 710 struct chardata chardata; /* set by get_logname() */ 711 struct termios termios; /* terminal mode bits */ 712 struct options options = { 713 0, /* show /etc/issue (SYSV_STYLE) */ 714 0, /* no timeout */ 715 _PATH_LOGIN, /* default login program */ 716 "tty1", /* default tty line */ 717 "", /* modem init string */ 718#ifdef ISSUE 719 ISSUE, /* default issue file */ 720#else 721 NULL, 722#endif 723 0, /* no baud rates known yet */ 724 }; 725 726 /* Already too late because of theoretical 727 * possibility of getty --help somehow triggered 728 * inadvertently before we reach this. Oh well. */ 729 logmode = LOGMODE_NONE; 730 setsid(); 731 nullfd = xopen(bb_dev_null, O_RDWR); 732 /* dup2(nullfd, 0); - no, because of possible "getty - 9600" */ 733 /* open_tty() will take care of fd# 0 anyway */ 734 dup2(nullfd, 1); 735 dup2(nullfd, 2); 736 while (nullfd > 2) close(nullfd--); 737 /* We want special flavor of error_msg_and_die */ 738 die_sleep = 10; 739 msg_eol = "\r\n"; 740 openlog(applet_name, LOG_PID, LOG_AUTH); 741 logmode = LOGMODE_BOTH; 742 743#ifdef DEBUGGING 744 dbf = xfopen(DEBUGTERM, "w"); 745 746 { 747 int i; 748 749 for (i = 1; i < argc; i++) { 750 debug(argv[i]); 751 debug("\n"); 752 } 753 } 754#endif 755 756 /* Parse command-line arguments. */ 757 parse_args(argc, argv, &options); 758 759#ifdef SYSV_STYLE 760#if ENABLE_FEATURE_UTMP 761 /* Update the utmp file. */ 762 update_utmp(options.tty); 763#endif 764#endif 765 766 debug("calling open_tty\n"); 767 /* Open the tty as standard { input, output, error }. */ 768 open_tty(options.tty, &termios, options.flags & F_LOCAL); 769 770#ifdef __linux__ 771 { 772 int iv; 773 774 iv = getpid(); 775 ioctl(0, TIOCSPGRP, &iv); 776 } 777#endif 778 /* Initialize the termios settings (raw mode, eight-bit, blocking i/o). */ 779 debug("calling termios_init\n"); 780 termios_init(&termios, options.speeds[FIRST_SPEED], &options); 781 782 /* write the modem init string and DON'T flush the buffers */ 783 if (options.flags & F_INITSTRING) { 784 debug("writing init string\n"); 785 write(1, options.initstring, strlen(options.initstring)); 786 } 787 788 if (!(options.flags & F_LOCAL)) { 789 /* go to blocking write mode unless -L is specified */ 790 ndelay_off(1); 791 } 792 793 /* Optionally detect the baud rate from the modem status message. */ 794 debug("before autobaud\n"); 795 if (options.flags & F_PARSE) 796 auto_baud(bb_common_bufsiz1, sizeof(bb_common_bufsiz1), &termios); 797 798 /* Set the optional timer. */ 799 if (options.timeout) 800 alarm(options.timeout); 801 802 /* optionally wait for CR or LF before writing /etc/issue */ 803 if (options.flags & F_WAITCRLF) { 804 char ch; 805 806 debug("waiting for cr-lf\n"); 807 while (read(0, &ch, 1) == 1) { 808 ch &= 0x7f; /* strip "parity bit" */ 809#ifdef DEBUGGING 810 fprintf(dbf, "read %c\n", ch); 811#endif 812 if (ch == '\n' || ch == '\r') 813 break; 814 } 815 } 816 817 chardata = init_chardata; 818 if (!(options.flags & F_NOPROMPT)) { 819 /* Read the login name. */ 820 debug("reading login name\n"); 821 logname = get_logname(bb_common_bufsiz1, sizeof(bb_common_bufsiz1), 822 &options, &chardata, &termios); 823 while (logname == NULL) 824 next_speed(&termios, &options); 825 } 826 827 /* Disable timer. */ 828 829 if (options.timeout) 830 alarm(0); 831 832 /* Finalize the termios settings. */ 833 834 termios_final(&options, &termios, &chardata); 835 836 /* Now the newline character should be properly written. */ 837 838 write(1, "\n", 1); 839 840 /* Let the login program take care of password validation. */ 841 842 execl(options.login, options.login, "--", logname, (char *) 0); 843 bb_error_msg_and_die("%s: can't exec %s", options.tty, options.login); 844} 845