login-utils/agetty.c

   1 /* agetty.c - another getty program for Linux. By W. Z. Venema 1989
   2    Ported to Linux by Peter Orbaek <poe@daimi.aau.dk>
   3    This program is freely distributable. The entire man-page used to
   4    be here. Now read the real man-page agetty.8 instead.
   5
   6    -f option added by Eric Rasmussen <ear@usfirst.org> - 12/28/95
   7 */
   8
   9 #include <stdio.h>
  10 #include <unistd.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/ioctl.h>
  14 #include <termio.h>
  15 #include <signal.h>
  16 #include <errno.h>
  17 #include <sys/types.h>
  18 #include <sys/stat.h>
  19 #include <fcntl.h>
  20 #include <varargs.h>
  21 #include <ctype.h>
  22 #include <utmp.h>
  23 #include <getopt.h>
  24 #include <memory.h>
  25 #include <sys/file.h>
  26
  27 #ifdef __linux__
  28 #include "pathnames.h"
  29 #include <sys/param.h>
  30 #define USE_SYSLOG
  31 #endif
  32
  33  /* If USE_SYSLOG is undefined all diagnostics go directly to /dev/console. */
  34
  35 #ifdef  USE_SYSLOG
  36 #include <syslog.h>
  37 extern void closelog();
  38 #endif
  39
  40  /*
  41   * Some heuristics to find out what environment we are in: if it is not
  42   * System V, assume it is SunOS 4.
  43   */
  44
  45 #ifdef LOGIN_PROCESS                    /* defined in System V utmp.h */
  46 #define SYSV_STYLE                      /* select System V style getty */
  47 #endif
  48
  49  /*
  50   * Things you may want to modify.
  51   *
  52   * If ISSUE is not defined, agetty will never display the contents of the
  53   * /etc/issue file. You will not want to spit out large "issue" files at the
  54   * wrong baud rate. Relevant for System V only.
  55   *
  56   * You may disagree with the default line-editing etc. characters defined
  57   * below. Note, however, that DEL cannot be used for interrupt generation
  58   * and for line editing at the same time.
  59   */
  60
  61 #ifdef  SYSV_STYLE
  62 #define ISSUE "/etc/issue"              /* displayed before the login prompt */
  63 #include <sys/utsname.h>
  64 #include <time.h>
  65 #endif
  66
  67 #define LOGIN " login: "                /* login prompt */
  68
  69 /* Some shorthands for control characters. */
  70
  71 #define CTL(x)          (x ^ 0100)      /* Assumes ASCII dialect */
  72 #define CR              CTL('M')        /* carriage return */
  73 #define NL              CTL('J')        /* line feed */
  74 #define BS              CTL('H')        /* back space */
  75 #define DEL             CTL('?')        /* delete */
  76
  77 /* Defaults for line-editing etc. characters; you may want to change this. */
  78
  79 #define DEF_ERASE       DEL             /* default erase character */
  80 #define DEF_INTR        CTL('C')        /* default interrupt character */
  81 #define DEF_QUIT        CTL('\\')       /* default quit char */
  82 #define DEF_KILL        CTL('U')        /* default kill char */
  83 #define DEF_EOF         CTL('D')        /* default EOF char */
  84 #define DEF_EOL         0
  85 #define DEF_SWITCH      0               /* default switch char */
  86
  87  /*
  88   * SunOS 4.1.1 termio is broken. We must use the termios stuff instead,
  89   * because the termio -> termios translation does not clear the termios
  90   * CIBAUD bits. Therefore, the tty driver would sometimes report that input
  91   * baud rate != output baud rate. I did not notice that problem with SunOS
  92   * 4.1. We will use termios where available, and termio otherwise.
  93   */
  94
  95 /* linux 0.12 termio is broken too, if we use it c_cc[VERASE] isn't set
  96    properly, but all is well if we use termios?! */
  97
  98 #ifdef  TCGETS
  99 #undef  TCGETA
 100 #undef  TCSETA
 101 #undef  TCSETAW
 102 #define termio  termios
 103 #define TCGETA  TCGETS
 104 #define TCSETA  TCSETS
 105 #define TCSETAW TCSETSW
 106 #endif
 107
 108  /*
 109   * This program tries to not use the standard-i/o library.  This keeps the
 110   * executable small on systems that do not have shared libraries (System V
 111   * Release <3).
 112   */
 113 #ifndef BUFSIZ
 114 #define BUFSIZ          1024
 115 #endif
 116
 117  /*
 118   * When multiple baud rates are specified on the command line, the first one
 119   * we will try is the first one specified.
 120   */
 121
 122 #define FIRST_SPEED     0
 123
 124 /* Storage for command-line options. */
 125
 126 #define MAX_SPEED       10              /* max. nr. of baud rates */
 127
 128 struct options {
 129     int     flags;                      /* toggle switches, see below */
 130     int     timeout;                    /* time-out period */
 131     char   *login;                      /* login program */
 132     char   *tty;                        /* name of tty */
 133     char   *initstring;                 /* modem init string */
 134     char   *issue;                      /* alternative issue file */
 135     int     numspeed;                   /* number of baud rates to try */
 136     int     speeds[MAX_SPEED];          /* baud rates to be tried */
 137 };
 138
 139 #define F_PARSE         (1<<0)          /* process modem status messages */
 140 #define F_ISSUE         (1<<1)          /* display /etc/issue */
 141 #define F_RTSCTS        (1<<2)          /* enable RTS/CTS flow control */
 142 #define F_LOCAL         (1<<3)          /* force local */
 143 #define F_INITSTRING    (1<<4)          /* initstring is set */
 144 #define F_WAITCRLF      (1<<5)          /* wait for CR or LF */
 145 #define F_CUSTISSUE     (1<<6)          /* give alternative issue file */
 146 #define F_NOPROMPT      (1<<7)          /* don't ask for login name! */
 147
 148 /* Storage for things detected while the login name was read. */
 149
 150 struct chardata {
 151     int     erase;                      /* erase character */
 152     int     kill;                       /* kill character */
 153     int     eol;                        /* end-of-line character */
 154     int     parity;                     /* what parity did we see */
 155     int     capslock;                   /* upper case without lower case */
 156 };
 157
 158 /* Initial values for the above. */
 159
 160 struct chardata init_chardata = {
 161     DEF_ERASE,                          /* default erase character */
 162     DEF_KILL,                           /* default kill character */
 163     13,                                 /* default eol char */
 164     0,                                  /* space parity */
 165     0,                                  /* no capslock */
 166 };
 167
 168 struct Speedtab {
 169     long    speed;
 170     int     code;
 171 };
 172
 173 static struct Speedtab speedtab[] = {
 174     { 50, B50 },
 175     { 75, B75 },
 176     { 110, B110 },
 177     { 134, B134 },
 178     { 150, B150 },
 179     { 200, B200 },
 180     { 300, B300 },
 181     { 600, B600 },
 182     { 1200, B1200 },
 183     { 1800, B1800 },
 184     { 2400, B2400 },
 185     { 4800, B4800 },
 186     { 9600, B9600 },
 187 #ifdef  B19200
 188     { 19200, B19200 },
 189 #endif
 190 #ifdef  B38400
 191     { 38400, B38400 },
 192 #endif
 193 #ifdef  EXTA
 194     { 19200, EXTA },
 195 #endif
 196 #ifdef  EXTB
 197     { 38400, EXTB },
 198 #endif
 199 #ifdef B57600
 200     { 57600, B57600 },
 201 #endif
 202 #ifdef B115200
 203     { 115200, B115200 },
 204 #endif
 205 #ifdef B230400
 206     { 230400, B230400 },
 207 #endif
 208     { 0, 0 },
 209 };
 210
 211 #define P_(s) ()
 212 void parse_args P_((int argc, char **argv, struct options *op));
 213 void parse_speeds P_((struct options *op, char *arg));
 214 void update_utmp P_((char *line));
 215 void open_tty P_((char *tty, struct termio *tp, int local));
 216 void termio_init P_((struct termio *tp, int speed, int local));
 217 void auto_baud P_((struct termio *tp));
 218 void do_prompt P_((struct options *op, struct termio *tp));
 219 void next_speed P_((struct termio *tp, struct options *op));
 220 char *get_logname P_((struct options *op, struct chardata *cp, struct termio *tp));
 221 void termio_final P_((struct options *op, struct termio *tp, struct chardata *cp));
 222 int caps_lock P_((char *s));
 223 int bcode P_((char *s));
 224 void usage P_((void));
 225 void error P_((int va_alist));
 226 #undef P_
 227
 228 /* The following is used for understandable diagnostics. */
 229
 230 char *progname;
 231
 232 /* ... */
 233 #ifdef DEBUGGING
 234 #define debug(s) fprintf(dbf,s); fflush(dbf)
 235 FILE *dbf;
 236 #else
 237 #define debug(s) /* nothing */
 238 #endif
 239
 240 int
 241 main(argc, argv)
 242      int     argc;
 243      char  **argv;
 244 {
 245     char   *logname = NULL;             /* login name, given to /bin/login */
 246     struct chardata chardata;           /* set by get_logname() */
 247     struct termio termio;               /* terminal mode bits */
 248     static struct options options = {
 249         F_ISSUE,                        /* show /etc/issue (SYSV_STYLE) */
 250         0,                              /* no timeout */
 251         _PATH_LOGIN,                    /* default login program */
 252         "tty1",                         /* default tty line */
 253         "",                             /* modem init string */
 254         ISSUE,                          /* default issue file */
 255         0,                              /* no baud rates known yet */
 256     };
 257
 258     /* The BSD-style init command passes us a useless process name. */
 259
 260 #ifdef  SYSV_STYLE
 261     progname = argv[0];
 262 #else
 263     progname = "agetty";
 264 #endif
 265
 266 #ifdef DEBUGGING
 267         dbf = fopen("/dev/ttyp0", "w");
 268
 269         {       int i;
 270
 271                 for(i = 1; i < argc; i++) {
 272                         debug(argv[i]);
 273                 }
 274         }
 275 #endif
 276
 277     /* Parse command-line arguments. */
 278
 279     parse_args(argc, argv, &options);
 280
 281 #ifdef __linux__
 282         setsid();
 283 #endif
 284
 285     /* Update the utmp file. */
 286
 287 #ifdef  SYSV_STYLE
 288     update_utmp(options.tty);
 289 #endif
 290
 291     debug("calling open_tty\n");
 292     /* Open the tty as standard { input, output, error }. */
 293     open_tty(options.tty, &termio, options.flags & F_LOCAL);
 294
 295 #ifdef __linux__
 296         {
 297                 int iv;
 298
 299                 iv = getpid();
 300                 (void) ioctl(0, TIOCSPGRP, &iv);
 301         }
 302 #endif
 303     /* Initialize the termio settings (raw mode, eight-bit, blocking i/o). */
 304     debug("calling termio_init\n");
 305     termio_init(&termio, options.speeds[FIRST_SPEED], options.flags & F_LOCAL);
 306
 307     /* write the modem init string and DON'T flush the buffers */
 308     if (options.flags & F_INITSTRING) {
 309         debug("writing init string\n");
 310         write(1, options.initstring, strlen(options.initstring));
 311     }
 312
 313     if (!(options.flags & F_LOCAL)) {
 314         /* go to blocking write mode unless -L is specified */
 315         fcntl(1, F_SETFL, fcntl(1, F_GETFL, 0) & ~O_NONBLOCK);
 316     }
 317
 318     /* Optionally detect the baud rate from the modem status message. */
 319     debug("before autobaud\n");
 320     if (options.flags & F_PARSE)
 321         auto_baud(&termio);
 322
 323     /* Set the optional timer. */
 324     if (options.timeout)
 325         (void) alarm((unsigned) options.timeout);
 326
 327     /* optionally wait for CR or LF before writing /etc/issue */
 328     if (options.flags & F_WAITCRLF) {
 329         char ch;
 330
 331         debug("waiting for cr-lf\n");
 332         while(read(0, &ch, 1) == 1) {
 333             ch &= 0x7f;   /* strip "parity bit" */
 334 #ifdef DEBUGGING
 335             fprintf(dbf, "read %c\n", ch);
 336 #endif
 337             if (ch == '\n' || ch == '\r') break;
 338         }
 339     }
 340
 341     chardata = init_chardata;
 342     if (!(options.flags & F_NOPROMPT)) {
 343         /* Read the login name. */
 344         debug("reading login name\n");
 345         while ((logname = get_logname(&options, &chardata, &termio)) == 0)
 346           next_speed(&termio, &options);
 347     }
 348
 349     /* Disable timer. */
 350
 351     if (options.timeout)
 352         (void) alarm(0);
 353
 354     /* Finalize the termio settings. */
 355
 356     termio_final(&options, &termio, &chardata);
 357
 358     /* Now the newline character should be properly written. */
 359
 360     (void) write(1, "\n", 1);
 361
 362     /* Let the login program take care of password validation. */
 363
 364     (void) execl(options.login, options.login, "--", logname, (char *) 0);
 365     error("%s: can't exec %s: %m", options.tty, options.login);
 366     exit(0);  /* quiet GCC */
 367 }
 368
 369 /* parse-args - parse command-line arguments */
 370
 371 void
 372 parse_args(argc, argv, op)
 373      int     argc;
 374      char  **argv;
 375      struct options *op;
 376 {
 377     extern char *optarg;                /* getopt */
 378     extern int optind;                  /* getopt */
 379     int     c;
 380
 381     while (isascii(c = getopt(argc, argv, "I:Lf:hil:mt:wn"))) {
 382         switch (c) {
 383         case 'I':
 384             if (!(op->initstring = malloc(strlen(optarg)))) {
 385                 error("can't malloc initstring");
 386                 break;
 387             }
 388             {
 389                 char ch, *p, *q;
 390                 int i;
 391
 392                 /* copy optarg into op->initstring decoding \ddd
 393                    octal codes into chars */
 394                 q = op->initstring;
 395                 p = optarg;
 396                 while (*p) {
 397                     if (*p == '\\') {           /* know \\ means \ */
 398                         p++;
 399                         if (*p == '\\') {
 400                             ch = '\\';
 401                             p++;
 402                         } else {                /* handle \000 - \177 */
 403                             ch = 0;
 404                             for (i = 1; i <= 3; i++) {
 405                                 if (*p >= '0' && *p <= '7') {
 406                                     ch <<= 3;
 407                                     ch += *p - '0';
 408                                     p++;
 409                                 } else
 410                                   break;
 411                             }
 412                         }
 413                         *q++ = ch;
 414                     } else {
 415                         *q++ = *p++;
 416                     }
 417                 }
 418                 *q = '\0';
 419             }
 420             op->flags |= F_INITSTRING;
 421             break;
 422
 423         case 'L':                               /* force local */
 424             op->flags |= F_LOCAL;
 425             break;
 426         case 'f':                               /* custom issue file */
 427             op->flags |= F_CUSTISSUE;
 428             op->issue = optarg;
 429             break;
 430         case 'h':                               /* enable h/w flow control */
 431             op->flags |= F_RTSCTS;
 432             break;
 433         case 'i':                               /* do not show /etc/issue */
 434             op->flags &= ~F_ISSUE;
 435             break;
 436         case 'l':
 437             op->login = optarg;                 /* non-default login program */
 438             break;
 439         case 'm':                               /* parse modem status message */
 440             op->flags |= F_PARSE;
 441             break;
 442         case 'n':
 443             op->flags |= F_NOPROMPT;
 444             break;
 445         case 't':                               /* time out */
 446             if ((op->timeout = atoi(optarg)) <= 0)
 447                 error("bad timeout value: %s", optarg);
 448             break;
 449         case 'w':
 450             op->flags |= F_WAITCRLF;
 451             break;
 452         default:
 453             usage();
 454         }
 455     }
 456         debug("after getopt loop\n");
 457     if (argc < optind + 2)                      /* check parameter count */
 458         usage();
 459
 460     /* we loosen up a bit and accept both "baudrate tty" and "tty baudrate" */
 461     if('0' <= argv[optind][0] && argv[optind][0] <= '9') {
 462         /* a number first, assume it's a speed (BSD style) */
 463         parse_speeds(op, argv[optind++]);       /* baud rate(s) */
 464         op->tty = argv[optind];                 /* tty name */
 465     } else {
 466         op->tty = argv[optind++];               /* tty name */
 467         parse_speeds(op, argv[optind]);         /* baud rate(s) */
 468     }
 469
 470     optind++;
 471     if (argc > optind && argv[optind])
 472         setenv ("TERM", argv[optind], 1);
 473
 474     debug("exiting parseargs\n");
 475 }
 476
 477 /* parse_speeds - parse alternate baud rates */
 478
 479 void
 480 parse_speeds(op, arg)
 481      struct options *op;
 482      char   *arg;
 483 {
 484     char   *strtok();
 485     char   *cp;
 486
 487         debug("entered parse_speeds\n");
 488     for (cp = strtok(arg, ","); cp != 0; cp = strtok((char *) 0, ",")) {
 489         if ((op->speeds[op->numspeed++] = bcode(cp)) <= 0)
 490             error("bad speed: %s", cp);
 491         if (op->numspeed > MAX_SPEED)
 492             error("too many alternate speeds");
 493     }
 494     debug("exiting parsespeeds\n");
 495 }
 496
 497 #ifdef  SYSV_STYLE
 498
 499 /* update_utmp - update our utmp entry */
 500 void
 501 update_utmp(line)
 502      char   *line;
 503 {
 504     struct  utmp ut;
 505     time_t  t;
 506     int     ut_fd;
 507     int     mypid = getpid();
 508     long    time();
 509     long    lseek();
 510     struct  utmp *utp;
 511
 512     /*
 513      * The utmp file holds miscellaneous information about things started by
 514      * /sbin/init and other system-related events. Our purpose is to update
 515      * the utmp entry for the current process, in particular the process type
 516      * and the tty line we are listening to. Return successfully only if the
 517      * utmp file can be opened for update, and if we are able to find our
 518      * entry in the utmp file.
 519      */
 520
 521 #ifdef __linux__
 522     utmpname(_PATH_UTMP);
 523     setutent();
 524     while ((utp = getutent())
 525            && !(utp->ut_type == INIT_PROCESS
 526                 && utp->ut_pid == mypid)) /* nothing */;
 527
 528     if (utp) {
 529         memcpy(&ut, utp, sizeof(ut));
 530     } else {
 531         /* some inits don't initialize utmp... */
 532         memset(&ut, 0, sizeof(ut));
 533         strncpy(ut.ut_id, line + 3, sizeof(ut.ut_id));
 534     }
 535     /*endutent();*/
 536
 537     strncpy(ut.ut_user, "LOGIN", sizeof(ut.ut_user));
 538     strncpy(ut.ut_line, line, sizeof(ut.ut_line));
 539     time(&t);
 540     ut.ut_time = t;
 541     ut.ut_type = LOGIN_PROCESS;
 542     ut.ut_pid = mypid;
 543
 544     pututline(&ut);
 545     endutent();
 546
 547     {
 548 #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1)
 549         updwtmp(_PATH_WTMP, &ut);
 550 #else
 551         int lf;
 552
 553         if ((lf = open(_PATH_WTMPLOCK, O_CREAT|O_WRONLY, 0660)) >= 0) {
 554             flock(lf, LOCK_EX);
 555             if ((ut_fd = open(_PATH_WTMP, O_APPEND|O_WRONLY)) >= 0) {
 556                 write(ut_fd, &ut, sizeof(ut));
 557                 close(ut_fd);
 558             }
 559             flock(lf, LOCK_UN);
 560             close(lf);
 561         }
 562 #endif
 563     }
 564 #else /* not __linux__ */
 565     if ((ut_fd = open(UTMP_FILE, 2)) < 0) {
 566         error("%s: open for update: %m", UTMP_FILE);
 567     } else {
 568         long    ut_size = sizeof(ut);       /* avoid nonsense */
 569
 570         while (read(ut_fd, (char *) &ut, sizeof(ut)) == sizeof(ut)) {
 571             if (ut.ut_type == INIT_PROCESS && ut.ut_pid == mypid) {
 572                 ut.ut_type = LOGIN_PROCESS;
 573                 ut.ut_time = time((long *) 0);
 574                 (void) strncpy(ut.ut_name, "LOGIN", sizeof(ut.ut_name));
 575                 (void) strncpy(ut.ut_line, line, sizeof(ut.ut_line));
 576                 (void) lseek(ut_fd, -ut_size, 1);
 577                 (void) write(ut_fd, (char *) &ut, sizeof(ut));
 578                 (void) close(ut_fd);
 579                 return;
 580             }
 581         }
 582         error("%s: no utmp entry", line);
 583     }
 584 #endif /* __linux__ */
 585 }
 586
 587 #endif
 588
 589 /* open_tty - set up tty as standard { input, output, error } */
 590 void
 591 open_tty(tty, tp, local)
 592      char   *tty;
 593      struct termio *tp;
 594      int    local;
 595 {
 596     /* Get rid of the present standard { output, error} if any. */
 597
 598     (void) close(1);
 599     (void) close(2);
 600     errno = 0;                                  /* ignore above errors */
 601
 602     /* Set up new standard input, unless we are given an already opened port. */
 603
 604     if (strcmp(tty, "-")) {
 605         struct stat st;
 606
 607         /* Sanity checks... */
 608
 609         if (chdir("/dev"))
 610             error("/dev: chdir() failed: %m");
 611         if (stat(tty, &st) < 0)
 612             error("/dev/%s: %m", tty);
 613         if ((st.st_mode & S_IFMT) != S_IFCHR)
 614             error("/dev/%s: not a character device", tty);
 615
 616         /* Open the tty as standard input. */
 617
 618         (void) close(0);
 619         errno = 0;                              /* ignore close(2) errors */
 620
 621         debug("open(2)\n");
 622         if (open(tty, O_RDWR|O_NONBLOCK, 0) != 0)
 623             error("/dev/%s: cannot open as standard input: %m", tty);
 624
 625     } else {
 626
 627         /*
 628          * Standard input should already be connected to an open port. Make
 629          * sure it is open for read/write.
 630          */
 631
 632         if ((fcntl(0, F_GETFL, 0) & O_RDWR) != O_RDWR)
 633             error("%s: not open for read/write", tty);
 634     }
 635
 636     /* Set up standard output and standard error file descriptors. */
 637     debug("duping\n");
 638     if (dup(0) != 1 || dup(0) != 2)             /* set up stdout and stderr */
 639         error("%s: dup problem: %m", tty);      /* we have a problem */
 640
 641     /*
 642      * The following ioctl will fail if stdin is not a tty, but also when
 643      * there is noise on the modem control lines. In the latter case, the
 644      * common course of action is (1) fix your cables (2) give the modem more
 645      * time to properly reset after hanging up. SunOS users can achieve (2)
 646      * by patching the SunOS kernel variable "zsadtrlow" to a larger value;
 647      * 5 seconds seems to be a good value.
 648      */
 649
 650     if (ioctl(0, TCGETA, tp) < 0)
 651         error("%s: ioctl: %m", tty);
 652
 653     /*
 654      * It seems to be a terminal. Set proper protections and ownership. Mode
 655      * 0622 is suitable for SYSV <4 because /bin/login does not change
 656      * protections. SunOS 4 login will change the protections to 0620 (write
 657      * access for group tty) after the login has succeeded.
 658      */
 659
 660     (void) chown(tty, 0, 0);                    /* root, sys */
 661     (void) chmod(tty, 0622);                    /* crw--w--w- */
 662     errno = 0;                                  /* ignore above errors */
 663 }
 664
 665 /* termio_init - initialize termio settings */
 666
 667 char gbuf[1024];
 668 char area[1024];
 669
 670 void
 671 termio_init(tp, speed, local)
 672      struct termio *tp;
 673      int     speed;
 674      int        local;
 675 {
 676
 677     /*
 678      * Initial termio settings: 8-bit characters, raw-mode, blocking i/o.
 679      * Special characters are set after we have read the login name; all
 680      * reads will be done in raw mode anyway. Errors will be dealt with
 681      * lateron.
 682      */
 683 #ifdef __linux__
 684     /* flush input and output queues, important for modems! */
 685     (void) ioctl(0, TCFLSH, TCIOFLUSH);
 686 #endif
 687
 688     tp->c_cflag = CS8 | HUPCL | CREAD | speed;
 689     if (local) {
 690         tp->c_cflag |= CLOCAL;
 691     }
 692
 693     tp->c_iflag = tp->c_lflag = tp->c_oflag = tp->c_line = 0;
 694     tp->c_cc[VMIN] = 1;
 695     tp->c_cc[VTIME] = 0;
 696     (void) ioctl(0, TCSETA, tp);
 697
 698     /* go to blocking input even in local mode */
 699     fcntl(0, F_SETFL, fcntl(0, F_GETFL, 0) & ~O_NONBLOCK);
 700
 701     debug("term_io 2\n");
 702 }
 703
 704 /* auto_baud - extract baud rate from modem status message */
 705 void
 706 auto_baud(tp)
 707      struct termio *tp;
 708 {
 709     int     speed;
 710     int     vmin;
 711     unsigned iflag;
 712     char    buf[BUFSIZ];
 713     char   *bp;
 714     int     nread;
 715
 716     /*
 717      * This works only if the modem produces its status code AFTER raising
 718      * the DCD line, and if the computer is fast enough to set the proper
 719      * baud rate before the message has gone by. We expect a message of the
 720      * following format:
 721      *
 722      * <junk><number><junk>
 723      *
 724      * The number is interpreted as the baud rate of the incoming call. If the
 725      * modem does not tell us the baud rate within one second, we will keep
 726      * using the current baud rate. It is advisable to enable BREAK
 727      * processing (comma-separated list of baud rates) if the processing of
 728      * modem status messages is enabled.
 729      */
 730
 731     /*
 732      * Use 7-bit characters, don't block if input queue is empty. Errors will
 733      * be dealt with lateron.
 734      */
 735
 736     iflag = tp->c_iflag;
 737     tp->c_iflag |= ISTRIP;                      /* enable 8th-bit stripping */
 738     vmin = tp->c_cc[VMIN];
 739     tp->c_cc[VMIN] = 0;                         /* don't block if queue empty */
 740     (void) ioctl(0, TCSETA, tp);
 741
 742     /*
 743      * Wait for a while, then read everything the modem has said so far and
 744      * try to extract the speed of the dial-in call.
 745      */
 746
 747     (void) sleep(1);
 748     if ((nread = read(0, buf, sizeof(buf) - 1)) > 0) {
 749         buf[nread] = '\0';
 750         for (bp = buf; bp < buf + nread; bp++) {
 751             if (isascii(*bp) && isdigit(*bp)) {
 752                 if ((speed = bcode(bp))) {
 753                     tp->c_cflag &= ~CBAUD;
 754                     tp->c_cflag |= speed;
 755                 }
 756                 break;
 757             }
 758         }
 759     }
 760     /* Restore terminal settings. Errors will be dealt with lateron. */
 761
 762     tp->c_iflag = iflag;
 763     tp->c_cc[VMIN] = vmin;
 764     (void) ioctl(0, TCSETA, tp);
 765 }
 766
 767 /* do_prompt - show login prompt, optionally preceded by /etc/issue contents */
 768 void
 769 do_prompt(op, tp)
 770      struct options *op;
 771      struct termio *tp;
 772 {
 773 #ifdef  ISSUE
 774     FILE    *fd;
 775     int     oflag;
 776     int     c;
 777     struct utsname uts;
 778
 779     (void) uname(&uts);
 780 #endif
 781
 782     (void) write(1, "\r\n", 2);                 /* start a new line */
 783 #ifdef  ISSUE                                   /* optional: show /etc/issue */
 784     if ((op->flags & F_ISSUE) && (fd = fopen(op->issue, "r"))) {
 785         oflag = tp->c_oflag;                    /* save current setting */
 786         tp->c_oflag |= (ONLCR | OPOST);         /* map NL in output to CR-NL */
 787         (void) ioctl(0, TCSETAW, tp);
 788
 789
 790         while ((c = getc(fd)) != EOF)
 791         {
 792             if (c == '\\')
 793               {
 794                 c = getc(fd);
 795
 796                 switch (c)
 797                   {
 798                   case 's':
 799                     (void) printf ("%s", uts.sysname);
 800                     break;
 801
 802                   case 'n':
 803                     (void) printf ("%s", uts.nodename);
 804                     break;
 805
 806                   case 'r':
 807                     (void) printf ("%s", uts.release);
 808                     break;
 809
 810                   case 'v':
 811                     (void) printf ("%s", uts.version);
 812                     break;
 813
 814                   case 'm':
 815                     (void) printf ("%s", uts.machine);
 816                     break;
 817
 818                   case 'o':
 819                    {
 820                      char domainname[256];
 821
 822                      getdomainname(domainname, sizeof(domainname));
 823                      domainname[sizeof(domainname)-1] = '\0';
 824                      printf ("%s", domainname);
 825                    }
 826                   break;
 827
 828                   case 'd':
 829                   case 't':
 830                     {
 831                       char *weekday[] = { "Sun", "Mon", "Tue", "Wed", "Thu",
 832                                           "Fri", "Sat" };
 833                       char *month[] = { "Jan", "Feb", "Mar", "Apr", "May",
 834                                         "Jun", "Jul", "Aug", "Sep", "Oct",
 835                                         "Nov", "Dec" };
 836                       time_t now;
 837                       struct tm *tm;
 838
 839                       (void) time (&now);
 840                       tm = localtime(&now);
 841
 842                       if (c == 'd')
 843                         (void) printf ("%s %s %d  %d",
 844                                 weekday[tm->tm_wday], month[tm->tm_mon],
 845                                 tm->tm_mday,
 846                                 tm->tm_year < 70 ? tm->tm_year + 2000 :
 847                                 tm->tm_year + 1900);
 848                       else
 849                         (void) printf ("%02d:%02d:%02d",
 850                                 tm->tm_hour, tm->tm_min, tm->tm_sec);
 851
 852                       break;
 853                     }
 854
 855                   case 'l':
 856                       (void) printf ("%s", op->tty);
 857                       break;
 858
 859                   case 'b':
 860                     {
 861                         int i;
 862
 863                         for (i = 0; speedtab[i].speed; i++) {
 864                             if (speedtab[i].code == (tp->c_cflag & CBAUD)) {
 865                                 printf("%ld", speedtab[i].speed);
 866                                 break;
 867                             }
 868                         }
 869                         break;
 870                     }
 871                   case 'u':
 872                   case 'U':
 873                     {
 874                       int users = 0;
 875                       struct utmp *ut;
 876                       setutent();
 877                       while ((ut = getutent()))
 878                         if (ut->ut_type == USER_PROCESS)
 879                           users++;
 880                       endutent();
 881                       printf ("%d", users);
 882                       if (c == 'U')
 883                         printf (" user%s", users == 1 ? "" : "s");
 884                       break;
 885                     }
 886                   default:
 887                     (void) putchar(c);
 888                   }
 889               }
 890             else
 891               (void) putchar(c);
 892         }
 893         fflush(stdout);
 894
 895         tp->c_oflag = oflag;                    /* restore settings */
 896         (void) ioctl(0, TCSETAW, tp);           /* wait till output is gone */
 897         (void) fclose(fd);
 898     }
 899 #endif
 900 #ifdef __linux__
 901         {
 902                 char hn[MAXHOSTNAMELEN+1];
 903
 904                 (void) gethostname(hn, MAXHOSTNAMELEN);
 905                 write(1, hn, strlen(hn));
 906         }
 907 #endif
 908     (void) write(1, LOGIN, sizeof(LOGIN) - 1);  /* always show login prompt */
 909 }
 910
 911 /* next_speed - select next baud rate */
 912 void
 913 next_speed(tp, op)
 914      struct termio *tp;
 915      struct options *op;
 916 {
 917     static int baud_index = FIRST_SPEED;/* current speed index */
 918
 919     baud_index = (baud_index + 1) % op->numspeed;
 920     tp->c_cflag &= ~CBAUD;
 921     tp->c_cflag |= op->speeds[baud_index];
 922     (void) ioctl(0, TCSETA, tp);
 923 }
 924
 925 /* get_logname - get user name, establish parity, speed, erase, kill, eol */
 926
 927 char   *get_logname(op, cp, tp)
 928      struct options *op;
 929      struct chardata *cp;
 930      struct termio *tp;
 931 {
 932     static char logname[BUFSIZ];
 933     char   *bp;
 934     char    c;                          /* input character, full eight bits */
 935     char    ascval;                     /* low 7 bits of input character */
 936     int     bits;                       /* # of "1" bits per character */
 937     int     mask;                       /* mask with 1 bit up */
 938     static char *erase[] = {            /* backspace-space-backspace */
 939         "\010\040\010",                 /* space parity */
 940         "\010\040\010",                 /* odd parity */
 941         "\210\240\210",                 /* even parity */
 942         "\210\240\210",                 /* no parity */
 943     };
 944
 945     /* Initialize kill, erase, parity etc. (also after switching speeds). */
 946
 947     *cp = init_chardata;
 948
 949     /* Flush pending input (esp. after parsing or switching the baud rate). */
 950
 951     (void) sleep(1);
 952     (void) ioctl(0, TCFLSH, TCIFLUSH);
 953
 954     /* Prompt for and read a login name. */
 955
 956     for (*logname = 0; *logname == 0; /* void */ ) {
 957
 958         /* Write issue file and prompt, with "parity" bit == 0. */
 959
 960         do_prompt(op, tp);
 961
 962         /* Read name, watch for break, parity, erase, kill, end-of-line. */
 963
 964         for (bp = logname, cp->eol = 0; cp->eol == 0; /* void */ ) {
 965
 966             /* Do not report trivial EINTR/EIO errors. */
 967
 968             if (read(0, &c, 1) < 1) {
 969                 if (errno == EINTR || errno == EIO)
 970                     exit(0);
 971                 error("%s: read: %m", op->tty);
 972             }
 973             /* Do BREAK handling elsewhere. */
 974
 975             if ((c == 0) && op->numspeed > 1)
 976                 return (0);
 977
 978             /* Do parity bit handling. */
 979
 980             if (c != (ascval = (c & 0177))) {   /* "parity" bit on ? */
 981                 for (bits = 1, mask = 1; mask & 0177; mask <<= 1)
 982                     if (mask & ascval)
 983                         bits++;                 /* count "1" bits */
 984                 cp->parity |= ((bits & 1) ? 1 : 2);
 985             }
 986             /* Do erase, kill and end-of-line processing. */
 987
 988             switch (ascval) {
 989             case CR:
 990             case NL:
 991                 *bp = 0;                        /* terminate logname */
 992                 cp->eol = ascval;               /* set end-of-line char */
 993                 break;
 994             case BS:
 995             case DEL:
 996             case '#':
 997                 cp->erase = ascval;             /* set erase character */
 998                 if (bp > logname) {
 999                     (void) write(1, erase[cp->parity], 3);
1000                     bp--;
1001                 }
1002                 break;
1003             case CTL('U'):
1004             case '@':
1005                 cp->kill = ascval;              /* set kill character */
1006                 while (bp > logname) {
1007                     (void) write(1, erase[cp->parity], 3);
1008                     bp--;
1009                 }
1010                 break;
1011             case CTL('D'):
1012                 exit(0);
1013             default:
1014                 if (!isascii(ascval) || !isprint(ascval)) {
1015                      /* ignore garbage characters */ ;
1016                 } else if (bp - logname >= sizeof(logname) - 1) {
1017                     error("%s: input overrun", op->tty);
1018                 } else {
1019                     (void) write(1, &c, 1);     /* echo the character */
1020                     *bp++ = ascval;             /* and store it */
1021                 }
1022                 break;
1023             }
1024         }
1025     }
1026     /* Handle names with upper case and no lower case. */
1027
1028     if ((cp->capslock = caps_lock(logname))) {
1029         for (bp = logname; *bp; bp++)
1030             if (isupper(*bp))
1031                 *bp = tolower(*bp);             /* map name to lower case */
1032     }
1033     return (logname);
1034 }
1035
1036 /* termio_final - set the final tty mode bits */
1037 void
1038 termio_final(op, tp, cp)
1039      struct options *op;
1040      struct termio *tp;
1041      struct chardata *cp;
1042 {
1043     /* General terminal-independent stuff. */
1044
1045     tp->c_iflag |= IXON | IXOFF;                /* 2-way flow control */
1046     tp->c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK| ECHOKE;
1047       /* no longer| ECHOCTL | ECHOPRT*/
1048     tp->c_oflag |= OPOST;
1049     /* tp->c_cflag = 0; */
1050     tp->c_cc[VINTR] = DEF_INTR;                 /* default interrupt */
1051     tp->c_cc[VQUIT] = DEF_QUIT;                 /* default quit */
1052     tp->c_cc[VEOF] = DEF_EOF;                   /* default EOF character */
1053     tp->c_cc[VEOL] = DEF_EOL;
1054 #ifdef __linux__
1055     tp->c_cc[VSWTC] = DEF_SWITCH;               /* default switch character */
1056 #else
1057     tp->c_cc[VSWTCH] = DEF_SWITCH;              /* default switch character */
1058 #endif
1059
1060     /* Account for special characters seen in input. */
1061
1062     if (cp->eol == CR) {
1063         tp->c_iflag |= ICRNL;                   /* map CR in input to NL */
1064         tp->c_oflag |= ONLCR;                   /* map NL in output to CR-NL */
1065     }
1066     tp->c_cc[VERASE] = cp->erase;               /* set erase character */
1067     tp->c_cc[VKILL] = cp->kill;                 /* set kill character */
1068
1069     /* Account for the presence or absence of parity bits in input. */
1070
1071     switch (cp->parity) {
1072     case 0:                                     /* space (always 0) parity */
1073         break;
1074     case 1:                                     /* odd parity */
1075         tp->c_cflag |= PARODD;
1076         /* FALLTHROUGH */
1077     case 2:                                     /* even parity */
1078         tp->c_cflag |= PARENB;
1079         tp->c_iflag |= INPCK | ISTRIP;
1080         /* FALLTHROUGH */
1081     case (1 | 2):                               /* no parity bit */
1082         tp->c_cflag &= ~CSIZE;
1083         tp->c_cflag |= CS7;
1084         break;
1085     }
1086     /* Account for upper case without lower case. */
1087
1088     if (cp->capslock) {
1089         tp->c_iflag |= IUCLC;
1090         tp->c_lflag |= XCASE;
1091         tp->c_oflag |= OLCUC;
1092     }
1093     /* Optionally enable hardware flow control */
1094
1095 #ifdef  CRTSCTS
1096     if (op->flags & F_RTSCTS)
1097         tp->c_cflag |= CRTSCTS;
1098 #endif
1099
1100     /* Finally, make the new settings effective */
1101
1102     if (ioctl(0, TCSETA, tp) < 0)
1103         error("%s: ioctl: TCSETA: %m", op->tty);
1104 }
1105
1106 /* caps_lock - string contains upper case without lower case */
1107 int
1108 caps_lock(s)
1109      char   *s;
1110 {
1111     int     capslock;
1112
1113     for (capslock = 0; *s; s++) {
1114         if (islower(*s))
1115             return (0);
1116         if (capslock == 0)
1117             capslock = isupper(*s);
1118     }
1119     return (capslock);
1120 }
1121
1122 /* bcode - convert speed string to speed code; return 0 on failure */
1123 int
1124 bcode(s)
1125      char   *s;
1126 {
1127     struct Speedtab *sp;
1128     long    speed = atol(s);
1129
1130     for (sp = speedtab; sp->speed; sp++)
1131         if (sp->speed == speed)
1132             return (sp->code);
1133     return (0);
1134 }
1135
1136 /* usage - explain */
1137
1138 void
1139 usage()
1140 {
1141     static char msg[] =
1142     "[-hiLmw] [-l login_program] [-t timeout] [-I initstring] baud_rate,... line [termtype]\nor\t[-hiLmw] [-l login_program] [-t timeout] [-I initstring] line baud_rate,... [termtype]";
1143
1144     fprintf(stderr, "Usage: %s %s\n", progname, msg);
1145     exit(1);
1146 }
1147
1148 /* error - report errors to console or syslog; only understands %s and %m */
1149
1150 #define str2cpy(b,s1,s2)        strcat(strcpy(b,s1),s2)
1151
1152 /* VARARGS */
1153 void
1154 error(va_alist)
1155      va_dcl
1156 {
1157     va_list ap;
1158     char   *fmt;
1159 #ifndef USE_SYSLOG
1160     int     fd;
1161 #endif
1162     char    buf[BUFSIZ];
1163     char   *bp;
1164
1165     /*
1166      * If the diagnostic is reported via syslog(3), the process name is
1167      * automatically prepended to the message. If we write directly to
1168      * /dev/console, we must prepend the process name ourselves.
1169      */
1170
1171 #ifdef USE_SYSLOG
1172     buf[0] = '\0';
1173     bp = buf;
1174 #else
1175     (void) str2cpy(buf, progname, ": ");
1176     bp = buf + strlen(buf);
1177 #endif
1178
1179     /*
1180      * %s expansion is done by hand. On a System V Release 2 system without
1181      * shared libraries and without syslog(3), linking with the the stdio
1182      * library would make the program three times as big...
1183      *
1184      * %m expansion is done here as well. Too bad syslog(3) does not have a
1185      * vsprintf() like interface.
1186      */
1187
1188     va_start(ap);
1189     fmt = va_arg(ap, char *);
1190     while (*fmt) {
1191         if (strncmp(fmt, "%s", 2) == 0) {
1192             (void) strcpy(bp, va_arg(ap, char *));
1193             bp += strlen(bp);
1194             fmt += 2;
1195         } else if (strncmp(fmt, "%m", 2) == 0) {
1196             (void) strcpy(bp, sys_errlist[errno]);
1197             bp += strlen(bp);
1198             fmt += 2;
1199         } else {
1200             *bp++ = *fmt++;
1201         }
1202     }
1203     *bp = 0;
1204     va_end(ap);
1205
1206     /*
1207      * Write the diagnostic directly to /dev/console if we do not use the
1208      * syslog(3) facility.
1209      */
1210
1211 #ifdef  USE_SYSLOG
1212     (void) openlog(progname, LOG_PID, LOG_AUTHPRIV);
1213     (void) syslog(LOG_ERR, "%s", buf);
1214     closelog();
1215 #else
1216     /* Terminate with CR-LF since the console mode is unknown. */
1217     (void) strcat(bp, "\r\n");
1218     if ((fd = open("/dev/console", 1)) >= 0) {
1219         (void) write(fd, buf, strlen(buf));
1220         (void) close(fd);
1221     }
1222 #endif
1223     (void) sleep((unsigned) 10);                        /* be kind to init(8) */
1224     exit(1);
1225 }