telnetd.tproj/telnetd.c

   1 /*
   2  * Copyright (c) 1989, 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
  34 #ifndef lint
  35 static const char copyright[] =
  36 "@(#) Copyright (c) 1989, 1993\n\
  37         The Regents of the University of California.  All rights reserved.\n";
  38 #endif /* not lint */
  39
  40 #ifndef lint
  41 #if 0
  42 static char sccsid[] = "@(#)telnetd.c   8.2 (Berkeley) 12/15/93";
  43 #endif
  44 static const char rcsid[] =
  45   "$FreeBSD: src/libexec/telnetd/telnetd.c,v 1.28 2001/07/20 15:14:03 ru Exp $";
  46 #endif /* not lint */
  47
  48 #include "telnetd.h"
  49 #include "pathnames.h"
  50
  51 #if     defined(_SC_CRAY_SECURE_SYS) && !defined(SCM_SECURITY)
  52 /*
  53  * UNICOS 6.0/6.1 do not have SCM_SECURITY defined, so we can
  54  * use it to tell us to turn off all the socket security code,
  55  * since that is only used in UNICOS 7.0 and later.
  56  */
  57 # undef _SC_CRAY_SECURE_SYS
  58 #endif
  59
  60 #include <err.h>
  61 #include <arpa/inet.h>
  62 #include <util.h>
  63 #include <sys/mman.h>
  64 #include <paths.h>
  65 #include <utmp.h>
  66 #include <sys/types.h>
  67
  68 #if     defined(_SC_CRAY_SECURE_SYS)
  69 #include <sys/sysv.h>
  70 #include <sys/secdev.h>
  71 # ifdef SO_SEC_MULTI            /* 8.0 code */
  72 #include <sys/secparm.h>
  73 #include <sys/usrv.h>
  74 # endif /* SO_SEC_MULTI */
  75
  76 /* wrapper for KAME-special getnameinfo() */
  77 #ifndef NI_WITHSCOPEID
  78 #define NI_WITHSCOPEID  0
  79 #endif
  80
  81 int     secflag;
  82 char    tty_dev[16];
  83 struct  secdev dv;
  84 struct  sysv sysv;
  85 # ifdef SO_SEC_MULTI            /* 8.0 code */
  86 struct  socksec ss;
  87 # else /* SO_SEC_MULTI */       /* 7.0 code */
  88 struct  socket_security ss;
  89 # endif /* SO_SEC_MULTI */
  90 #endif  /* _SC_CRAY_SECURE_SYS */
  91
  92 #if     defined(AUTHENTICATION)
  93 #include <libtelnet/auth.h>
  94 int     auth_level = 0;
  95 #endif
  96 #if     defined(SecurID)
  97 int     require_SecurID = 0;
  98 #endif
  99
 100 char    remote_hostname[MAXHOSTNAMELEN];
 101 int     utmp_len = sizeof(remote_hostname) - 1;
 102 int     registerd_host_only = 0;
 103
 104 #ifdef  STREAMSPTY
 105 # include <stropts.h>
 106 # include <termio.h>
 107 /* make sure we don't get the bsd version */
 108 # include "/usr/include/sys/tty.h"
 109 # include <sys/ptyvar.h>
 110
 111 /*
 112  * Because of the way ptyibuf is used with streams messages, we need
 113  * ptyibuf+1 to be on a full-word boundary.  The following weirdness
 114  * is simply to make that happen.
 115  */
 116 long    ptyibufbuf[BUFSIZ/sizeof(long)+1];
 117 char    *ptyibuf = ((char *)&ptyibufbuf[1])-1;
 118 char    *ptyip = ((char *)&ptyibufbuf[1])-1;
 119 char    ptyibuf2[BUFSIZ];
 120 unsigned char ctlbuf[BUFSIZ];
 121 struct  strbuf strbufc, strbufd;
 122
 123 int readstream();
 124
 125 #else   /* ! STREAMPTY */
 126
 127 /*
 128  * I/O data buffers,
 129  * pointers, and counters.
 130  */
 131 char    ptyibuf[BUFSIZ], *ptyip = ptyibuf;
 132 char    ptyibuf2[BUFSIZ];
 133
 134 #endif /* ! STREAMPTY */
 135
 136 int     hostinfo = 1;                   /* do we print login banner? */
 137
 138 #ifdef  CRAY
 139 extern int      newmap; /* nonzero if \n maps to ^M^J */
 140 int     lowpty = 0, highpty;    /* low, high pty numbers */
 141 #endif /* CRAY */
 142
 143 int debug = 0;
 144 int keepalive = 1;
 145 char *altlogin;
 146
 147 void doit __P((struct sockaddr *));
 148 int terminaltypeok __P((char *));
 149 void startslave __P((char *, int, char *));
 150 extern void usage P((void));
 151
 152 /*
 153  * The string to pass to getopt().  We do it this way so
 154  * that only the actual options that we support will be
 155  * passed off to getopt().
 156  */
 157 char valid_opts[] = {
 158         'd', ':', 'h', 'k', 'n', 'p', ':', 'S', ':', 'u', ':', 'U',
 159         '4', '6',
 160 #ifdef  AUTHENTICATION
 161         'a', ':', 'X', ':',
 162 #endif
 163 #ifdef BFTPDAEMON
 164         'B',
 165 #endif
 166 #ifdef DIAGNOSTICS
 167         'D', ':',
 168 #endif
 169 #if     defined(CRAY) && defined(NEWINIT)
 170         'I', ':',
 171 #endif
 172 #ifdef  LINEMODE
 173         'l',
 174 #endif
 175 #ifdef CRAY
 176         'r', ':',
 177 #endif
 178 #ifdef  SecurID
 179         's',
 180 #endif
 181         '\0'
 182 };
 183
 184 int family = AF_INET;
 185
 186 int
 187 main(argc, argv)
 188         char *argv[];
 189 {
 190         struct sockaddr_storage from;
 191         int on = 1, fromlen;
 192         register int ch;
 193 #if     defined(IPPROTO_IP) && defined(IP_TOS)
 194         int tos = -1;
 195 #endif
 196
 197         pfrontp = pbackp = ptyobuf;
 198         netip = netibuf;
 199         nfrontp = nbackp = netobuf;
 200
 201         /*
 202          * This initialization causes linemode to default to a configuration
 203          * that works on all telnet clients, including the FreeBSD client.
 204          * This is not quite the same as the telnet client issuing a "mode
 205          * character" command, but has most of the same benefits, and is
 206          * preferable since some clients (like usofts) don't have the
 207          * mode character command anyway and linemode breaks things.
 208          * The most notable symptom of fix is that csh "set filec" operations
 209          * like <ESC> (filename completion) and ^D (choices) keys now work
 210          * in telnet sessions and can be used more than once on the same line.
 211          * CR/LF handling is also corrected in some termio modes.  This
 212          * change resolves problem reports bin/771 and bin/1037.
 213          */
 214
 215         linemode=1;     /*Default to mode that works on bulk of clients*/
 216
 217 #ifdef CRAY
 218         /*
 219          * Get number of pty's before trying to process options,
 220          * which may include changing pty range.
 221          */
 222         highpty = getnpty();
 223 #endif /* CRAY */
 224
 225         while ((ch = getopt(argc, argv, valid_opts)) != -1) {
 226                 switch(ch) {
 227
 228 #ifdef  AUTHENTICATION
 229                 case 'a':
 230                         /*
 231                          * Check for required authentication level
 232                          */
 233                         if (strcmp(optarg, "debug") == 0) {
 234                                 extern int auth_debug_mode;
 235                                 auth_debug_mode = 1;
 236                         } else if (strcasecmp(optarg, "none") == 0) {
 237                                 auth_level = 0;
 238                         } else if (strcasecmp(optarg, "other") == 0) {
 239                                 auth_level = AUTH_OTHER;
 240                         } else if (strcasecmp(optarg, "user") == 0) {
 241                                 auth_level = AUTH_USER;
 242                         } else if (strcasecmp(optarg, "valid") == 0) {
 243                                 auth_level = AUTH_VALID;
 244                         } else if (strcasecmp(optarg, "off") == 0) {
 245                                 /*
 246                                  * This hack turns off authentication
 247                                  */
 248                                 auth_level = -1;
 249                         } else {
 250                                 warnx("unknown authorization level for -a");
 251                         }
 252                         break;
 253 #endif  /* AUTHENTICATION */
 254
 255 #ifdef BFTPDAEMON
 256                 case 'B':
 257                         bftpd++;
 258                         break;
 259 #endif /* BFTPDAEMON */
 260
 261                 case 'd':
 262                         if (strcmp(optarg, "ebug") == 0) {
 263                                 debug++;
 264                                 break;
 265                         }
 266                         usage();
 267                         /* NOTREACHED */
 268                         break;
 269
 270 #ifdef DIAGNOSTICS
 271                 case 'D':
 272                         /*
 273                          * Check for desired diagnostics capabilities.
 274                          */
 275                         if (!strcmp(optarg, "report")) {
 276                                 diagnostic |= TD_REPORT|TD_OPTIONS;
 277                         } else if (!strcmp(optarg, "exercise")) {
 278                                 diagnostic |= TD_EXERCISE;
 279                         } else if (!strcmp(optarg, "netdata")) {
 280                                 diagnostic |= TD_NETDATA;
 281                         } else if (!strcmp(optarg, "ptydata")) {
 282                                 diagnostic |= TD_PTYDATA;
 283                         } else if (!strcmp(optarg, "options")) {
 284                                 diagnostic |= TD_OPTIONS;
 285                         } else {
 286                                 usage();
 287                                 /* NOT REACHED */
 288                         }
 289                         break;
 290 #endif /* DIAGNOSTICS */
 291
 292
 293                 case 'h':
 294                         hostinfo = 0;
 295                         break;
 296
 297 #if     defined(CRAY) && defined(NEWINIT)
 298                 case 'I':
 299                     {
 300                         extern char *gen_id;
 301                         gen_id = optarg;
 302                         break;
 303                     }
 304 #endif  /* defined(CRAY) && defined(NEWINIT) */
 305
 306 #ifdef  LINEMODE
 307                 case 'l':
 308                         alwayslinemode = 1;
 309                         break;
 310 #endif  /* LINEMODE */
 311
 312                 case 'k':
 313 #if     defined(LINEMODE) && defined(KLUDGELINEMODE)
 314                         lmodetype = NO_AUTOKLUDGE;
 315 #else
 316                         /* ignore -k option if built without kludge linemode */
 317 #endif  /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
 318                         break;
 319
 320                 case 'n':
 321                         keepalive = 0;
 322                         break;
 323
 324                 case 'p':
 325                         altlogin = optarg;
 326                         break;
 327
 328 #ifdef CRAY
 329                 case 'r':
 330                     {
 331                         char *strchr();
 332                         char *c;
 333
 334                         /*
 335                          * Allow the specification of alterations
 336                          * to the pty search range.  It is legal to
 337                          * specify only one, and not change the
 338                          * other from its default.
 339                          */
 340                         c = strchr(optarg, '-');
 341                         if (c) {
 342                                 *c++ = '\0';
 343                                 highpty = atoi(c);
 344                         }
 345                         if (*optarg != '\0')
 346                                 lowpty = atoi(optarg);
 347                         if ((lowpty > highpty) || (lowpty < 0) ||
 348                                                         (highpty > 32767)) {
 349                                 usage();
 350                                 /* NOT REACHED */
 351                         }
 352                         break;
 353                     }
 354 #endif  /* CRAY */
 355
 356 #ifdef  SecurID
 357                 case 's':
 358                         /* SecurID required */
 359                         require_SecurID = 1;
 360                         break;
 361 #endif  /* SecurID */
 362                 case 'S':
 363 #ifdef  HAS_GETTOS
 364                         if ((tos = parsetos(optarg, "tcp")) < 0)
 365                                 warnx("%s%s%s",
 366                                         "bad TOS argument '", optarg,
 367                                         "'; will try to use default TOS");
 368 #else
 369                         warnx("TOS option unavailable; -S flag not supported");
 370 #endif
 371                         break;
 372
 373                 case 'u':
 374                         utmp_len = atoi(optarg);
 375                         if (utmp_len < 0)
 376                                 utmp_len = -utmp_len;
 377                         if (utmp_len >= sizeof(remote_hostname))
 378                                 utmp_len = sizeof(remote_hostname) - 1;
 379                         break;
 380
 381                 case 'U':
 382                         registerd_host_only = 1;
 383                         break;
 384
 385 #ifdef  AUTHENTICATION
 386                 case 'X':
 387                         /*
 388                          * Check for invalid authentication types
 389                          */
 390                         auth_disable_name(optarg);
 391                         break;
 392 #endif  /* AUTHENTICATION */
 393
 394                 case '4':
 395                         family = AF_INET;
 396                         break;
 397
 398 #ifdef INET6
 399                 case '6':
 400                         family = AF_INET6;
 401                         break;
 402 #endif
 403
 404                 default:
 405                         warnx("%c: unknown option", ch);
 406                         /* FALLTHROUGH */
 407                 case '?':
 408                         usage();
 409                         /* NOTREACHED */
 410                 }
 411         }
 412
 413         argc -= optind;
 414         argv += optind;
 415
 416         if (debug) {
 417             int s, ns, foo, error;
 418             char *service = "telnet";
 419             struct addrinfo hints, *res;
 420
 421             if (argc > 1) {
 422                 usage();
 423                 /* NOT REACHED */
 424             } else if (argc == 1)
 425                 service = *argv;
 426
 427             memset(&hints, 0, sizeof(hints));
 428             hints.ai_flags = AI_PASSIVE;
 429             hints.ai_family = family;
 430             hints.ai_socktype = SOCK_STREAM;
 431             hints.ai_protocol = 0;
 432             error = getaddrinfo(NULL, service, &hints, &res);
 433
 434             if (error) {
 435                 errx(1, "tcp/%s: %s\n", service, gai_strerror(error));
 436                 if (error == EAI_SYSTEM)
 437                     errx(1, "tcp/%s: %s\n", service, strerror(errno));
 438                 usage();
 439             }
 440
 441             s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
 442             if (s < 0)
 443                     err(1, "socket");
 444             (void) setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
 445                                 (char *)&on, sizeof(on));
 446             if (bind(s, res->ai_addr, res->ai_addrlen) < 0)
 447                 err(1, "bind");
 448             if (listen(s, 1) < 0)
 449                 err(1, "listen");
 450             foo = res->ai_addrlen;
 451             ns = accept(s, res->ai_addr, &foo);
 452             if (ns < 0)
 453                 err(1, "accept");
 454             (void) dup2(ns, 0);
 455             (void) close(ns);
 456             (void) close(s);
 457 #ifdef convex
 458         } else if (argc == 1) {
 459                 ; /* VOID*/             /* Just ignore the host/port name */
 460 #endif
 461         } else if (argc > 0) {
 462                 usage();
 463                 /* NOT REACHED */
 464         }
 465
 466 #if     defined(_SC_CRAY_SECURE_SYS)
 467         secflag = sysconf(_SC_CRAY_SECURE_SYS);
 468
 469         /*
 470          *      Get socket's security label
 471          */
 472         if (secflag)  {
 473                 int szss = sizeof(ss);
 474 #ifdef SO_SEC_MULTI                     /* 8.0 code */
 475                 int sock_multi;
 476                 int szi = sizeof(int);
 477 #endif /* SO_SEC_MULTI */
 478
 479                 bzero((char *)&dv, sizeof(dv));
 480
 481                 if (getsysv(&sysv, sizeof(struct sysv)) != 0)
 482                         err(1, "getsysv");
 483
 484                 /*
 485                  *      Get socket security label and set device values
 486                  *         {security label to be set on ttyp device}
 487                  */
 488 #ifdef SO_SEC_MULTI                     /* 8.0 code */
 489                 if ((getsockopt(0, SOL_SOCKET, SO_SECURITY,
 490                                (char *)&ss, &szss) < 0) ||
 491                     (getsockopt(0, SOL_SOCKET, SO_SEC_MULTI,
 492                                 (char *)&sock_multi, &szi) < 0)) {
 493                         err(1, "getsockopt");
 494                 } else {
 495                         dv.dv_actlvl = ss.ss_actlabel.lt_level;
 496                         dv.dv_actcmp = ss.ss_actlabel.lt_compart;
 497                         if (!sock_multi) {
 498                                 dv.dv_minlvl = dv.dv_maxlvl = dv.dv_actlvl;
 499                                 dv.dv_valcmp = dv.dv_actcmp;
 500                         } else {
 501                                 dv.dv_minlvl = ss.ss_minlabel.lt_level;
 502                                 dv.dv_maxlvl = ss.ss_maxlabel.lt_level;
 503                                 dv.dv_valcmp = ss.ss_maxlabel.lt_compart;
 504                         }
 505                         dv.dv_devflg = 0;
 506                 }
 507 #else /* SO_SEC_MULTI */                /* 7.0 code */
 508                 if (getsockopt(0, SOL_SOCKET, SO_SECURITY,
 509                                 (char *)&ss, &szss) >= 0) {
 510                         dv.dv_actlvl = ss.ss_slevel;
 511                         dv.dv_actcmp = ss.ss_compart;
 512                         dv.dv_minlvl = ss.ss_minlvl;
 513                         dv.dv_maxlvl = ss.ss_maxlvl;
 514                         dv.dv_valcmp = ss.ss_maxcmp;
 515                 }
 516 #endif /* SO_SEC_MULTI */
 517         }
 518 #endif  /* _SC_CRAY_SECURE_SYS */
 519
 520         openlog("telnetd", LOG_PID | LOG_ODELAY, LOG_DAEMON);
 521         fromlen = sizeof (from);
 522         if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) {
 523                 warn("getpeername");
 524                 _exit(1);
 525         }
 526         if (keepalive &&
 527             setsockopt(0, SOL_SOCKET, SO_KEEPALIVE,
 528                         (char *)&on, sizeof (on)) < 0) {
 529                 syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
 530         }
 531
 532 #if     defined(IPPROTO_IP) && defined(IP_TOS)
 533         if (from.ss_family == AF_INET) {
 534 # if    defined(HAS_GETTOS)
 535                 struct tosent *tp;
 536                 if (tos < 0 && (tp = gettosbyname("telnet", "tcp")))
 537                         tos = tp->t_tos;
 538 # endif
 539                 if (tos < 0)
 540                         tos = 020;      /* Low Delay bit */
 541                 if (tos
 542                    && (setsockopt(0, IPPROTO_IP, IP_TOS,
 543                                   (char *)&tos, sizeof(tos)) < 0)
 544                    && (errno != ENOPROTOOPT) )
 545                         syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
 546         }
 547 #endif  /* defined(IPPROTO_IP) && defined(IP_TOS) */
 548         net = 0;
 549         doit((struct sockaddr *)&from);
 550         /* NOTREACHED */
 551         return(0);
 552 }  /* end of main */
 553
 554         void
 555 usage()
 556 {
 557         fprintf(stderr, "usage: telnetd");
 558 #ifdef  AUTHENTICATION
 559         fprintf(stderr, " [-a (debug|other|user|valid|off|none)]\n\t");
 560 #endif
 561 #ifdef BFTPDAEMON
 562         fprintf(stderr, " [-B]");
 563 #endif
 564         fprintf(stderr, " [-debug]");
 565 #ifdef DIAGNOSTICS
 566         fprintf(stderr, " [-D (options|report|exercise|netdata|ptydata)]\n\t");
 567 #endif
 568 #ifdef  AUTHENTICATION
 569         fprintf(stderr, " [-edebug]");
 570 #endif
 571         fprintf(stderr, " [-h]");
 572 #if     defined(CRAY) && defined(NEWINIT)
 573         fprintf(stderr, " [-Iinitid]");
 574 #endif
 575 #if     defined(LINEMODE) && defined(KLUDGELINEMODE)
 576         fprintf(stderr, " [-k]");
 577 #endif
 578 #ifdef LINEMODE
 579         fprintf(stderr, " [-l]");
 580 #endif
 581         fprintf(stderr, " [-n]");
 582 #ifdef  CRAY
 583         fprintf(stderr, " [-r[lowpty]-[highpty]]");
 584 #endif
 585         fprintf(stderr, "\n\t");
 586 #ifdef  SecurID
 587         fprintf(stderr, " [-s]");
 588 #endif
 589 #ifdef  HAS_GETTOS
 590         fprintf(stderr, " [-S tos]");
 591 #endif
 592 #ifdef  AUTHENTICATION
 593         fprintf(stderr, " [-X auth-type]");
 594 #endif
 595         fprintf(stderr, " [-u utmp_hostname_length] [-U]");
 596         fprintf(stderr, " [port]\n");
 597         exit(1);
 598 }
 599
 600 /*
 601  * getterminaltype
 602  *
 603  *      Ask the other end to send along its terminal type and speed.
 604  * Output is the variable terminaltype filled in.
 605  */
 606 static unsigned char ttytype_sbbuf[] = {
 607         IAC, SB, TELOPT_TTYPE, TELQUAL_SEND, IAC, SE
 608 };
 609
 610     int
 611 getterminaltype(name)
 612     char *name;
 613 {
 614     int retval = -1;
 615     void _gettermname();
 616
 617     settimer(baseline);
 618 #if     defined(AUTHENTICATION)
 619     /*
 620      * Handle the Authentication option before we do anything else.
 621      */
 622     send_do(TELOPT_AUTHENTICATION, 1);
 623     while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
 624         ttloop();
 625     if (his_state_is_will(TELOPT_AUTHENTICATION)) {
 626         retval = auth_wait(name);
 627     }
 628 #endif
 629
 630     send_do(TELOPT_TTYPE, 1);
 631     send_do(TELOPT_TSPEED, 1);
 632     send_do(TELOPT_XDISPLOC, 1);
 633     send_do(TELOPT_NEW_ENVIRON, 1);
 634     send_do(TELOPT_OLD_ENVIRON, 1);
 635     while (
 636            his_will_wont_is_changing(TELOPT_TTYPE) ||
 637            his_will_wont_is_changing(TELOPT_TSPEED) ||
 638            his_will_wont_is_changing(TELOPT_XDISPLOC) ||
 639            his_will_wont_is_changing(TELOPT_NEW_ENVIRON) ||
 640            his_will_wont_is_changing(TELOPT_OLD_ENVIRON)) {
 641         ttloop();
 642     }
 643     if (his_state_is_will(TELOPT_TSPEED)) {
 644         static unsigned char sb[] =
 645                         { IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE };
 646
 647         output_datalen(sb, sizeof sb);
 648     }
 649     if (his_state_is_will(TELOPT_XDISPLOC)) {
 650         static unsigned char sb[] =
 651                         { IAC, SB, TELOPT_XDISPLOC, TELQUAL_SEND, IAC, SE };
 652
 653         output_datalen(sb, sizeof sb);
 654     }
 655     if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
 656         static unsigned char sb[] =
 657                         { IAC, SB, TELOPT_NEW_ENVIRON, TELQUAL_SEND, IAC, SE };
 658
 659         output_datalen(sb, sizeof sb);
 660     }
 661     else if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
 662         static unsigned char sb[] =
 663                         { IAC, SB, TELOPT_OLD_ENVIRON, TELQUAL_SEND, IAC, SE };
 664
 665         output_datalen(sb, sizeof sb);
 666     }
 667     if (his_state_is_will(TELOPT_TTYPE)) {
 668
 669         output_datalen(ttytype_sbbuf, sizeof ttytype_sbbuf);
 670     }
 671     if (his_state_is_will(TELOPT_TSPEED)) {
 672         while (sequenceIs(tspeedsubopt, baseline))
 673             ttloop();
 674     }
 675     if (his_state_is_will(TELOPT_XDISPLOC)) {
 676         while (sequenceIs(xdisplocsubopt, baseline))
 677             ttloop();
 678     }
 679     if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
 680         while (sequenceIs(environsubopt, baseline))
 681             ttloop();
 682     }
 683     if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
 684         while (sequenceIs(oenvironsubopt, baseline))
 685             ttloop();
 686     }
 687     if (his_state_is_will(TELOPT_TTYPE)) {
 688         char first[256], last[256];
 689
 690         while (sequenceIs(ttypesubopt, baseline))
 691             ttloop();
 692
 693         /*
 694          * If the other side has already disabled the option, then
 695          * we have to just go with what we (might) have already gotten.
 696          */
 697         if (his_state_is_will(TELOPT_TTYPE) && !terminaltypeok(terminaltype)) {
 698             (void) strncpy(first, terminaltype, sizeof(first)-1);
 699             first[sizeof(first)-1] = '\0';
 700             for(;;) {
 701                 /*
 702                  * Save the unknown name, and request the next name.
 703                  */
 704                 (void) strncpy(last, terminaltype, sizeof(last)-1);
 705                 last[sizeof(last)-1] = '\0';
 706                 _gettermname();
 707                 if (terminaltypeok(terminaltype))
 708                     break;
 709                 if ((strncmp(last, terminaltype, sizeof(last)) == 0) ||
 710                     his_state_is_wont(TELOPT_TTYPE)) {
 711                     /*
 712                      * We've hit the end.  If this is the same as
 713                      * the first name, just go with it.
 714                      */
 715                     if (strncmp(first, terminaltype, sizeof(first)) == 0)
 716                         break;
 717                     /*
 718                      * Get the terminal name one more time, so that
 719                      * RFC1091 compliant telnets will cycle back to
 720                      * the start of the list.
 721                      */
 722                      _gettermname();
 723                     if (strncmp(first, terminaltype, sizeof(first)) != 0) {
 724                         (void) strncpy(terminaltype, first, sizeof(terminaltype)-1);
 725                         terminaltype[sizeof(terminaltype)-1] = '\0';
 726                     }
 727                     break;
 728                 }
 729             }
 730         }
 731     }
 732     return(retval);
 733 }  /* end of getterminaltype */
 734
 735     void
 736 _gettermname()
 737 {
 738     /*
 739      * If the client turned off the option,
 740      * we can't send another request, so we
 741      * just return.
 742      */
 743     if (his_state_is_wont(TELOPT_TTYPE))
 744         return;
 745     settimer(baseline);
 746     output_datalen(ttytype_sbbuf, sizeof ttytype_sbbuf);
 747     while (sequenceIs(ttypesubopt, baseline))
 748         ttloop();
 749 }
 750
 751     int
 752 terminaltypeok(s)
 753     char *s;
 754 {
 755     char buf[1024];
 756
 757     if (terminaltype == NULL)
 758         return(1);
 759
 760     /*
 761      * tgetent() will return 1 if the type is known, and
 762      * 0 if it is not known.  If it returns -1, it couldn't
 763      * open the database.  But if we can't open the database,
 764      * it won't help to say we failed, because we won't be
 765      * able to verify anything else.  So, we treat -1 like 1.
 766      */
 767     if (tgetent(buf, s) == 0)
 768         return(0);
 769     return(1);
 770 }
 771
 772 #ifndef MAXHOSTNAMELEN
 773 #define MAXHOSTNAMELEN 256
 774 #endif  /* MAXHOSTNAMELEN */
 775
 776 char *hostname;
 777 char host_name[MAXHOSTNAMELEN];
 778
 779 extern void telnet P((int, int, char *));
 780
 781 int level;
 782 char user_name[256];
 783 /*
 784  * Get a pty, scan input lines.
 785  */
 786         void
 787 doit(who)
 788         struct sockaddr *who;
 789 {
 790         char *host = NULL;
 791         int err;
 792         struct hostent *hp;
 793         int ptynum;
 794
 795         /*
 796          * Find an available pty to use.
 797          */
 798 #ifndef convex
 799         pty = getpty(&ptynum);
 800         if (pty < 0)
 801                 fatal(net, "All network ports in use");
 802 #else
 803         for (;;) {
 804                 char *lp;
 805
 806                 if ((lp = getpty()) == NULL)
 807                         fatal(net, "Out of ptys");
 808
 809                 if ((pty = open(lp, 2)) >= 0) {
 810                         strlcpy(line,lp,sizeof(line));
 811                         line[5] = 't';
 812                         break;
 813                 }
 814         }
 815 #endif
 816
 817 #if     defined(_SC_CRAY_SECURE_SYS)
 818         /*
 819          *      set ttyp line security label
 820          */
 821         if (secflag) {
 822                 char slave_dev[16];
 823
 824                 sprintf(tty_dev, "%spty/%03d", _PATH_DEV, ptynum);
 825                 if (setdevs(tty_dev, &dv) < 0)
 826                         fatal(net, "cannot set pty security");
 827                 sprintf(slave_dev, "%sp%03d", _PATH_TTY, ptynum);
 828                 if (setdevs(slave_dev, &dv) < 0)
 829                         fatal(net, "cannot set tty security");
 830         }
 831 #endif  /* _SC_CRAY_SECURE_SYS */
 832
 833         /* get name of connected client */
 834         hp = gethostbyaddr((char *)&((struct sockaddr_in *)who)->sin_addr, sizeof (struct in_addr),
 835                 ((struct sockaddr_in *)who)->sin_family);
 836
 837         if (hp == NULL && registerd_host_only) {
 838                 fatal(net, "Couldn't resolve your address into a host name.\r\n\
 839          Please contact your net administrator");
 840         } else if (hp &&
 841             (strlen(hp->h_name) <= (unsigned int)((utmp_len < 0) ? -utmp_len
 842                                                                  : utmp_len))) {
 843                 host = hp->h_name;
 844         } else {
 845                 host = inet_ntoa(((struct sockaddr_in *)who)->sin_addr);
 846         }
 847         /*
 848          * We must make a copy because Kerberos is probably going
 849          * to also do a gethost* and overwrite the static data...
 850          */
 851         strncpy(remote_hostname, host, sizeof(remote_hostname)-1);
 852         remote_hostname[sizeof(remote_hostname)-1] = 0;
 853         host = remote_hostname;
 854
 855         (void) gethostname(host_name, sizeof(host_name) - 1);
 856         host_name[sizeof(host_name) - 1] = '\0';
 857         hostname = host_name;
 858
 859 #if     defined(AUTHENTICATION)
 860         auth_encrypt_init(hostname, remote_hostname, "TELNETD", 1);
 861 #endif
 862
 863         init_env();
 864         /*
 865          * get terminal type.
 866          */
 867         *user_name = 0;
 868         level = getterminaltype(user_name);
 869         setenv("TERM", terminaltype ? terminaltype : "network", 1);
 870
 871 #if     defined(_SC_CRAY_SECURE_SYS)
 872         if (secflag) {
 873                 if (setulvl(dv.dv_actlvl) < 0)
 874                         fatal(net,"cannot setulvl()");
 875                 if (setucmp(dv.dv_actcmp) < 0)
 876                         fatal(net, "cannot setucmp()");
 877         }
 878 #endif  /* _SC_CRAY_SECURE_SYS */
 879
 880         telnet(net, pty, remote_hostname);      /* begin server process */
 881
 882         /*NOTREACHED*/
 883 }  /* end of doit */
 884
 885 #if     defined(CRAY2) && defined(UNICOS5) && defined(UNICOS50)
 886         int
 887 Xterm_output(ibufp, obuf, icountp, ocount)
 888         char **ibufp, *obuf;
 889         int *icountp, ocount;
 890 {
 891         int ret;
 892         ret = term_output(*ibufp, obuf, *icountp, ocount);
 893         *ibufp += *icountp;
 894         *icountp = 0;
 895         return(ret);
 896 }
 897 #define term_output     Xterm_output
 898 #endif  /* defined(CRAY2) && defined(UNICOS5) && defined(UNICOS50) */
 899
 900 /*
 901  * Main loop.  Select from pty and network, and
 902  * hand data to telnet receiver finite state machine.
 903  */
 904         void
 905 telnet(f, p, host)
 906         int f, p;
 907         char *host;
 908 {
 909         int on = 1;
 910 #define TABBUFSIZ       512
 911         char    defent[TABBUFSIZ];
 912         char    defstrs[TABBUFSIZ];
 913 #undef  TABBUFSIZ
 914         char *HE;
 915         char *HN;
 916         char *IM;
 917         char *IF;
 918         char *if_buf;
 919         int if_fd;
 920         struct stat statbuf;
 921
 922         void netflush();
 923
 924         /*
 925          * Initialize the slc mapping table.
 926          */
 927         get_slc_defaults();
 928
 929         /*
 930          * Do some tests where it is desireable to wait for a response.
 931          * Rather than doing them slowly, one at a time, do them all
 932          * at once.
 933          */
 934         if (my_state_is_wont(TELOPT_SGA))
 935                 send_will(TELOPT_SGA, 1);
 936         /*
 937          * Is the client side a 4.2 (NOT 4.3) system?  We need to know this
 938          * because 4.2 clients are unable to deal with TCP urgent data.
 939          *
 940          * To find out, we send out a "DO ECHO".  If the remote system
 941          * answers "WILL ECHO" it is probably a 4.2 client, and we note
 942          * that fact ("WILL ECHO" ==> that the client will echo what
 943          * WE, the server, sends it; it does NOT mean that the client will
 944          * echo the terminal input).
 945          */
 946         send_do(TELOPT_ECHO, 1);
 947
 948 #ifdef  LINEMODE
 949         if (his_state_is_wont(TELOPT_LINEMODE)) {
 950                 /* Query the peer for linemode support by trying to negotiate
 951                  * the linemode option.
 952                  */
 953                 linemode = 0;
 954                 editmode = 0;
 955                 send_do(TELOPT_LINEMODE, 1);  /* send do linemode */
 956         }
 957 #endif  /* LINEMODE */
 958
 959         /*
 960          * Send along a couple of other options that we wish to negotiate.
 961          */
 962         send_do(TELOPT_NAWS, 1);
 963         send_will(TELOPT_STATUS, 1);
 964         flowmode = 1;           /* default flow control state */
 965         restartany = -1;        /* uninitialized... */
 966         send_do(TELOPT_LFLOW, 1);
 967
 968         /*
 969          * Spin, waiting for a response from the DO ECHO.  However,
 970          * some REALLY DUMB telnets out there might not respond
 971          * to the DO ECHO.  So, we spin looking for NAWS, (most dumb
 972          * telnets so far seem to respond with WONT for a DO that
 973          * they don't understand...) because by the time we get the
 974          * response, it will already have processed the DO ECHO.
 975          * Kludge upon kludge.
 976          */
 977         while (his_will_wont_is_changing(TELOPT_NAWS))
 978                 ttloop();
 979
 980         /*
 981          * But...
 982          * The client might have sent a WILL NAWS as part of its
 983          * startup code; if so, we'll be here before we get the
 984          * response to the DO ECHO.  We'll make the assumption
 985          * that any implementation that understands about NAWS
 986          * is a modern enough implementation that it will respond
 987          * to our DO ECHO request; hence we'll do another spin
 988          * waiting for the ECHO option to settle down, which is
 989          * what we wanted to do in the first place...
 990          */
 991         if (his_want_state_is_will(TELOPT_ECHO) &&
 992             his_state_is_will(TELOPT_NAWS)) {
 993                 while (his_will_wont_is_changing(TELOPT_ECHO))
 994                         ttloop();
 995         }
 996         /*
 997          * On the off chance that the telnet client is broken and does not
 998          * respond to the DO ECHO we sent, (after all, we did send the
 999          * DO NAWS negotiation after the DO ECHO, and we won't get here
1000          * until a response to the DO NAWS comes back) simulate the
1001          * receipt of a will echo.  This will also send a WONT ECHO
1002          * to the client, since we assume that the client failed to
1003          * respond because it believes that it is already in DO ECHO
1004          * mode, which we do not want.
1005          */
1006         if (his_want_state_is_will(TELOPT_ECHO)) {
1007                 DIAG(TD_OPTIONS, output_data("td: simulating recv\r\n"));
1008                 willoption(TELOPT_ECHO);
1009         }
1010
1011         /*
1012          * Finally, to clean things up, we turn on our echo.  This
1013          * will break stupid 4.2 telnets out of local terminal echo.
1014          */
1015
1016         if (my_state_is_wont(TELOPT_ECHO))
1017                 send_will(TELOPT_ECHO, 1);
1018
1019 #ifndef STREAMSPTY
1020         /*
1021          * Turn on packet mode
1022          */
1023         (void) ioctl(p, TIOCPKT, (char *)&on);
1024 #endif
1025
1026 #if     defined(LINEMODE) && defined(KLUDGELINEMODE)
1027         /*
1028          * Continuing line mode support.  If client does not support
1029          * real linemode, attempt to negotiate kludge linemode by sending
1030          * the do timing mark sequence.
1031          */
1032         if (lmodetype < REAL_LINEMODE)
1033                 send_do(TELOPT_TM, 1);
1034 #endif  /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
1035
1036         /*
1037          * Call telrcv() once to pick up anything received during
1038          * terminal type negotiation, 4.2/4.3 determination, and
1039          * linemode negotiation.
1040          */
1041         telrcv();
1042
1043         (void) ioctl(f, FIONBIO, (char *)&on);
1044         (void) ioctl(p, FIONBIO, (char *)&on);
1045 #if     defined(CRAY2) && defined(UNICOS5)
1046         init_termdriver(f, p, interrupt, sendbrk);
1047 #endif
1048
1049 #if     defined(SO_OOBINLINE)
1050         (void) setsockopt(net, SOL_SOCKET, SO_OOBINLINE,
1051                                 (char *)&on, sizeof on);
1052 #endif  /* defined(SO_OOBINLINE) */
1053
1054 #ifdef  SIGTSTP
1055         (void) signal(SIGTSTP, SIG_IGN);
1056 #endif
1057 #ifdef  SIGTTOU
1058         /*
1059          * Ignoring SIGTTOU keeps the kernel from blocking us
1060          * in ttioct() in /sys/tty.c.
1061          */
1062         (void) signal(SIGTTOU, SIG_IGN);
1063 #endif
1064
1065         (void) signal(SIGCHLD, cleanup);
1066
1067 #if     defined(CRAY2) && defined(UNICOS5)
1068         /*
1069          * Cray-2 will send a signal when pty modes are changed by slave
1070          * side.  Set up signal handler now.
1071          */
1072         if ((int)signal(SIGUSR1, termstat) < 0)
1073                 warn("signal");
1074         else if (ioctl(p, TCSIGME, (char *)SIGUSR1) < 0)
1075                 warn("ioctl:TCSIGME");
1076         /*
1077          * Make processing loop check terminal characteristics early on.
1078          */
1079         termstat();
1080 #endif
1081
1082 #ifdef  TIOCNOTTY
1083         {
1084                 register int t;
1085                 t = open(_PATH_TTY, O_RDWR);
1086                 if (t >= 0) {
1087                         (void) ioctl(t, TIOCNOTTY, (char *)0);
1088                         (void) close(t);
1089                 }
1090         }
1091 #endif
1092
1093 #if     defined(CRAY) && defined(NEWINIT) && defined(TIOCSCTTY)
1094         (void) setsid();
1095         ioctl(p, TIOCSCTTY, 0);
1096 #endif
1097
1098         /*
1099          * Show banner that getty never gave.
1100          *
1101          * We put the banner in the pty input buffer.  This way, it
1102          * gets carriage return null processing, etc., just like all
1103          * other pty --> client data.
1104          */
1105
1106 #if     !defined(CRAY) || !defined(NEWINIT)
1107         if (getenv("USER"))
1108                 hostinfo = 0;
1109 #endif
1110
1111         if (getent(defent, "default") == 1) {
1112                 char *Getstr();
1113                 char *cp=defstrs;
1114
1115                 HE = Getstr("he", &cp);
1116                 HN = Getstr("hn", &cp);
1117                 IM = Getstr("im", &cp);
1118                 IF = Getstr("if", &cp);
1119                 if (HN && *HN)
1120                         (void) strlcpy(host_name, HN, sizeof(host_name));
1121                 if (IF && (if_fd = open(IF, O_RDONLY, 000)) != -1)
1122                         IM = 0;
1123                 if (IM == 0)
1124                         IM = "";
1125         } else {
1126                 IM = DEFAULT_IM;
1127                 HE = 0;
1128         }
1129         edithost(HE, host_name);
1130         if (hostinfo && *IM)
1131                 putf(IM, ptyibuf2);
1132         else if (IF && if_fd != -1) {
1133                 fstat (if_fd, &statbuf);
1134                 if_buf = (char *) mmap (0, statbuf.st_size, PROT_READ,
1135                     0, if_fd, 0);
1136                 putf(if_buf, ptyibuf2);
1137                 munmap (if_buf, statbuf.st_size);
1138                 close (if_fd);
1139         }
1140
1141         if (pcc)
1142                 (void) strncat(ptyibuf2, ptyip, pcc+1);
1143         ptyip = ptyibuf2;
1144         pcc = strlen(ptyip);
1145 #ifdef  LINEMODE
1146         /*
1147          * Last check to make sure all our states are correct.
1148          */
1149         init_termbuf();
1150         localstat();
1151 #endif  /* LINEMODE */
1152
1153         DIAG(TD_REPORT, output_data("td: Entering processing loop\r\n"));
1154
1155         /*
1156          * Startup the login process on the slave side of the terminal
1157          * now.  We delay this until here to insure option negotiation
1158          * is complete.
1159          */
1160         startslave(host, level, user_name);
1161
1162         for (;;) {
1163                 fd_set ibits, obits, xbits;
1164                 register int c;
1165
1166                 if (ncc < 0 && pcc < 0)
1167                         break;
1168
1169 #if     defined(CRAY2) && defined(UNICOS5)
1170                 if (needtermstat)
1171                         _termstat();
1172 #endif  /* defined(CRAY2) && defined(UNICOS5) */
1173                 FD_ZERO(&ibits);
1174                 FD_ZERO(&obits);
1175                 FD_ZERO(&xbits);
1176                 /*
1177                  * Never look for input if there's still
1178                  * stuff in the corresponding output buffer
1179                  */
1180                 if (nfrontp - nbackp || pcc > 0) {
1181                         FD_SET(f, &obits);
1182                 } else {
1183                         FD_SET(p, &ibits);
1184                 }
1185                 if (pfrontp - pbackp || ncc > 0) {
1186                         FD_SET(p, &obits);
1187                 } else {
1188                         FD_SET(f, &ibits);
1189                 }
1190                 if (!SYNCHing) {
1191                         FD_SET(f, &xbits);
1192                 }
1193                 if ((c = select(16, &ibits, &obits, &xbits,
1194                                                 (struct timeval *)0)) < 1) {
1195                         if (c == -1) {
1196                                 if (errno == EINTR) {
1197                                         continue;
1198                                 }
1199                         }
1200                         sleep(5);
1201                         continue;
1202                 }
1203
1204                 /*
1205                  * Any urgent data?
1206                  */
1207                 if (FD_ISSET(net, &xbits)) {
1208                     SYNCHing = 1;
1209                 }
1210
1211                 /*
1212                  * Something to read from the network...
1213                  */
1214                 if (FD_ISSET(net, &ibits)) {
1215 #if     !defined(SO_OOBINLINE)
1216                         /*
1217                          * In 4.2 (and 4.3 beta) systems, the
1218                          * OOB indication and data handling in the kernel
1219                          * is such that if two separate TCP Urgent requests
1220                          * come in, one byte of TCP data will be overlaid.
1221                          * This is fatal for Telnet, but we try to live
1222                          * with it.
1223                          *
1224                          * In addition, in 4.2 (and...), a special protocol
1225                          * is needed to pick up the TCP Urgent data in
1226                          * the correct sequence.
1227                          *
1228                          * What we do is:  if we think we are in urgent
1229                          * mode, we look to see if we are "at the mark".
1230                          * If we are, we do an OOB receive.  If we run
1231                          * this twice, we will do the OOB receive twice,
1232                          * but the second will fail, since the second
1233                          * time we were "at the mark", but there wasn't
1234                          * any data there (the kernel doesn't reset
1235                          * "at the mark" until we do a normal read).
1236                          * Once we've read the OOB data, we go ahead
1237                          * and do normal reads.
1238                          *
1239                          * There is also another problem, which is that
1240                          * since the OOB byte we read doesn't put us
1241                          * out of OOB state, and since that byte is most
1242                          * likely the TELNET DM (data mark), we would
1243                          * stay in the TELNET SYNCH (SYNCHing) state.
1244                          * So, clocks to the rescue.  If we've "just"
1245                          * received a DM, then we test for the
1246                          * presence of OOB data when the receive OOB
1247                          * fails (and AFTER we did the normal mode read
1248                          * to clear "at the mark").
1249                          */
1250                     if (SYNCHing) {
1251                         int atmark;
1252
1253                         (void) ioctl(net, SIOCATMARK, (char *)&atmark);
1254                         if (atmark) {
1255                             ncc = recv(net, netibuf, sizeof (netibuf), MSG_OOB);
1256                             if ((ncc == -1) && (errno == EINVAL)) {
1257                                 ncc = read(net, netibuf, sizeof (netibuf));
1258                                 if (sequenceIs(didnetreceive, gotDM)) {
1259                                     SYNCHing = stilloob(net);
1260                                 }
1261                             }
1262                         } else {
1263                             ncc = read(net, netibuf, sizeof (netibuf));
1264                         }
1265                     } else {
1266                         ncc = read(net, netibuf, sizeof (netibuf));
1267                     }
1268                     settimer(didnetreceive);
1269 #else   /* !defined(SO_OOBINLINE)) */
1270                     ncc = read(net, netibuf, sizeof (netibuf));
1271 #endif  /* !defined(SO_OOBINLINE)) */
1272                     if (ncc < 0 && errno == EWOULDBLOCK)
1273                         ncc = 0;
1274                     else {
1275                         if (ncc <= 0) {
1276                             break;
1277                         }
1278                         netip = netibuf;
1279                     }
1280                     DIAG((TD_REPORT | TD_NETDATA),
1281                         output_data("td: netread %d chars\r\n", ncc));
1282                     DIAG(TD_NETDATA, printdata("nd", netip, ncc));
1283                 }
1284
1285                 /*
1286                  * Something to read from the pty...
1287                  */
1288                 if (FD_ISSET(p, &ibits)) {
1289 #ifndef STREAMSPTY
1290                         pcc = read(p, ptyibuf, BUFSIZ);
1291 #else
1292                         pcc = readstream(p, ptyibuf, BUFSIZ);
1293 #endif
1294                         /*
1295                          * On some systems, if we try to read something
1296                          * off the master side before the slave side is
1297                          * opened, we get EIO.
1298                          */
1299                         if (pcc < 0 && (errno == EWOULDBLOCK ||
1300 #ifdef  EAGAIN
1301                                         errno == EAGAIN ||
1302 #endif
1303                                         errno == EIO)) {
1304                                 pcc = 0;
1305                         } else {
1306                                 if (pcc <= 0)
1307                                         break;
1308 #if     !defined(CRAY2) || !defined(UNICOS5)
1309 #ifdef  LINEMODE
1310                                 /*
1311                                  * If ioctl from pty, pass it through net
1312                                  */
1313                                 if (ptyibuf[0] & TIOCPKT_IOCTL) {
1314                                         copy_termbuf(ptyibuf+1, pcc-1);
1315                                         localstat();
1316                                         pcc = 1;
1317                                 }
1318 #endif  /* LINEMODE */
1319                                 if (ptyibuf[0] & TIOCPKT_FLUSHWRITE) {
1320                                         netclear();     /* clear buffer back */
1321 #ifndef NO_URGENT
1322                                         /*
1323                                          * There are client telnets on some
1324                                          * operating systems get screwed up
1325                                          * royally if we send them urgent
1326                                          * mode data.
1327                                          */
1328                                         output_data("%c%c", IAC, DM);
1329                                         neturg = nfrontp-1; /* off by one XXX */
1330 #endif
1331                                 }
1332                                 if (his_state_is_will(TELOPT_LFLOW) &&
1333                                     (ptyibuf[0] &
1334                                      (TIOCPKT_NOSTOP|TIOCPKT_DOSTOP))) {
1335                                         int newflow =
1336                                             ptyibuf[0] & TIOCPKT_DOSTOP ? 1 : 0;
1337                                         if (newflow != flowmode) {
1338                                                 flowmode = newflow;
1339                                                 output_data("%c%c%c%c%c%c",
1340                                                         IAC, SB, TELOPT_LFLOW,
1341                                                         flowmode ? LFLOW_ON
1342                                                                  : LFLOW_OFF,
1343                                                         IAC, SE);
1344                                         }
1345                                 }
1346                                 pcc--;
1347                                 ptyip = ptyibuf+1;
1348 #else   /* defined(CRAY2) && defined(UNICOS5) */
1349                                 if (!uselinemode) {
1350                                         unpcc = pcc;
1351                                         unptyip = ptyibuf;
1352                                         pcc = term_output(&unptyip, ptyibuf2,
1353                                                                 &unpcc, BUFSIZ);
1354                                         ptyip = ptyibuf2;
1355                                 } else
1356                                         ptyip = ptyibuf;
1357 #endif  /* defined(CRAY2) && defined(UNICOS5) */
1358                         }
1359                 }
1360
1361                 while (pcc > 0) {
1362                         if ((&netobuf[BUFSIZ] - nfrontp) < 2)
1363                                 break;
1364                         c = *ptyip++ & 0377, pcc--;
1365                         if (c == IAC)
1366                                 output_data("%c", c);
1367 #if     defined(CRAY2) && defined(UNICOS5)
1368                         else if (c == '\n' &&
1369                                      my_state_is_wont(TELOPT_BINARY) && newmap)
1370                                 output_data("\r");
1371 #endif  /* defined(CRAY2) && defined(UNICOS5) */
1372                         output_data("%c", c);
1373                         if ((c == '\r') && (my_state_is_wont(TELOPT_BINARY))) {
1374                                 if (pcc > 0 && ((*ptyip & 0377) == '\n')) {
1375                                         output_data("%c", *ptyip++ & 0377);
1376                                         pcc--;
1377                                 } else
1378                                         output_data("%c", '\0');
1379                         }
1380                 }
1381 #if     defined(CRAY2) && defined(UNICOS5)
1382                 /*
1383                  * If chars were left over from the terminal driver,
1384                  * note their existence.
1385                  */
1386                 if (!uselinemode && unpcc) {
1387                         pcc = unpcc;
1388                         unpcc = 0;
1389                         ptyip = unptyip;
1390                 }
1391 #endif  /* defined(CRAY2) && defined(UNICOS5) */
1392
1393                 if (FD_ISSET(f, &obits) && (nfrontp - nbackp) > 0)
1394                         netflush();
1395                 if (ncc > 0)
1396                         telrcv();
1397                 if (FD_ISSET(p, &obits) && (pfrontp - pbackp) > 0)
1398                         ptyflush();
1399         }
1400         cleanup(0);
1401 }  /* end of telnet */
1402
1403 #ifndef TCSIG
1404 # ifdef TIOCSIG
1405 #  define TCSIG TIOCSIG
1406 # endif
1407 #endif
1408
1409 #ifdef  STREAMSPTY
1410
1411 int flowison = -1;  /* current state of flow: -1 is unknown */
1412
1413 int readstream(p, ibuf, bufsize)
1414         int p;
1415         char *ibuf;
1416         int bufsize;
1417 {
1418         int flags = 0;
1419         int ret = 0;
1420         struct termios *tsp;
1421         struct termio *tp;
1422         struct iocblk *ip;
1423         char vstop, vstart;
1424         int ixon;
1425         int newflow;
1426
1427         strbufc.maxlen = BUFSIZ;
1428         strbufc.buf = (char *)ctlbuf;
1429         strbufd.maxlen = bufsize-1;
1430         strbufd.len = 0;
1431         strbufd.buf = ibuf+1;
1432         ibuf[0] = 0;
1433
1434         ret = getmsg(p, &strbufc, &strbufd, &flags);
1435         if (ret < 0)  /* error of some sort -- probably EAGAIN */
1436                 return(-1);
1437
1438         if (strbufc.len <= 0 || ctlbuf[0] == M_DATA) {
1439                 /* data message */
1440                 if (strbufd.len > 0) {                  /* real data */
1441                         return(strbufd.len + 1);        /* count header char */
1442                 } else {
1443                         /* nothing there */
1444                         errno = EAGAIN;
1445                         return(-1);
1446                 }
1447         }
1448
1449         /*
1450          * It's a control message.  Return 1, to look at the flag we set
1451          */
1452
1453         switch (ctlbuf[0]) {
1454         case M_FLUSH:
1455                 if (ibuf[1] & FLUSHW)
1456                         ibuf[0] = TIOCPKT_FLUSHWRITE;
1457                 return(1);
1458
1459         case M_IOCTL:
1460                 ip = (struct iocblk *) (ibuf+1);
1461
1462                 switch (ip->ioc_cmd) {
1463                 case TCSETS:
1464                 case TCSETSW:
1465                 case TCSETSF:
1466                         tsp = (struct termios *)
1467                                         (ibuf+1 + sizeof(struct iocblk));
1468                         vstop = tsp->c_cc[VSTOP];
1469                         vstart = tsp->c_cc[VSTART];
1470                         ixon = tsp->c_iflag & IXON;
1471                         break;
1472                 case TCSETA:
1473                 case TCSETAW:
1474                 case TCSETAF:
1475                         tp = (struct termio *) (ibuf+1 + sizeof(struct iocblk));
1476                         vstop = tp->c_cc[VSTOP];
1477                         vstart = tp->c_cc[VSTART];
1478                         ixon = tp->c_iflag & IXON;
1479                         break;
1480                 default:
1481                         errno = EAGAIN;
1482                         return(-1);
1483                 }
1484
1485                 newflow =  (ixon && (vstart == 021) && (vstop == 023)) ? 1 : 0;
1486                 if (newflow != flowison) {  /* it's a change */
1487                         flowison = newflow;
1488                         ibuf[0] = newflow ? TIOCPKT_DOSTOP : TIOCPKT_NOSTOP;
1489                         return(1);
1490                 }
1491         }
1492
1493         /* nothing worth doing anything about */
1494         errno = EAGAIN;
1495         return(-1);
1496 }
1497 #endif /* STREAMSPTY */
1498
1499 /*
1500  * Send interrupt to process on other side of pty.
1501  * If it is in raw mode, just write NULL;
1502  * otherwise, write intr char.
1503  */
1504         void
1505 interrupt()
1506 {
1507         ptyflush();     /* half-hearted */
1508
1509 #ifdef  TCSIG
1510         (void) ioctl(pty, TCSIG, (char *)SIGINT);
1511 #else   /* TCSIG */
1512         init_termbuf();
1513         *pfrontp++ = slctab[SLC_IP].sptr ?
1514                         (unsigned char)*slctab[SLC_IP].sptr : '\177';
1515 #endif  /* TCSIG */
1516 }
1517
1518 /*
1519  * Send quit to process on other side of pty.
1520  * If it is in raw mode, just write NULL;
1521  * otherwise, write quit char.
1522  */
1523         void
1524 sendbrk()
1525 {
1526         ptyflush();     /* half-hearted */
1527 #ifdef  TCSIG
1528         (void) ioctl(pty, TCSIG, (char *)SIGQUIT);
1529 #else   /* TCSIG */
1530         init_termbuf();
1531         *pfrontp++ = slctab[SLC_ABORT].sptr ?
1532                         (unsigned char)*slctab[SLC_ABORT].sptr : '\034';
1533 #endif  /* TCSIG */
1534 }
1535
1536         void
1537 sendsusp()
1538 {
1539 #ifdef  SIGTSTP
1540         ptyflush();     /* half-hearted */
1541 # ifdef TCSIG
1542         (void) ioctl(pty, TCSIG, (char *)SIGTSTP);
1543 # else  /* TCSIG */
1544         *pfrontp++ = slctab[SLC_SUSP].sptr ?
1545                         (unsigned char)*slctab[SLC_SUSP].sptr : '\032';
1546 # endif /* TCSIG */
1547 #endif  /* SIGTSTP */
1548 }
1549
1550 /*
1551  * When we get an AYT, if ^T is enabled, use that.  Otherwise,
1552  * just send back "[Yes]".
1553  */
1554         void
1555 recv_ayt()
1556 {
1557 #if     defined(SIGINFO) && defined(TCSIG)
1558         if (slctab[SLC_AYT].sptr && *slctab[SLC_AYT].sptr != _POSIX_VDISABLE) {
1559                 (void) ioctl(pty, TCSIG, (char *)SIGINFO);
1560                 return;
1561         }
1562 #endif
1563         output_data("\r\n[Yes]\r\n");
1564 }
1565
1566         void
1567 doeof()
1568 {
1569         init_termbuf();
1570
1571 #if     defined(LINEMODE) && defined(USE_TERMIO) && (VEOF == VMIN)
1572         if (!tty_isediting()) {
1573                 extern char oldeofc;
1574                 *pfrontp++ = oldeofc;
1575                 return;
1576         }
1577 #endif
1578         *pfrontp++ = slctab[SLC_EOF].sptr ?
1579                         (unsigned char)*slctab[SLC_EOF].sptr : '\004';
1580 }