appl/telnet/telnetd/utility.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 #define PRINTOPTIONS
  35 #include "telnetd.h"
  36
  37 RCSID("$Id$");
  38
  39 /*
  40  * utility functions performing io related tasks
  41  */
  42
  43 /*
  44  * ttloop
  45  *
  46  * A small subroutine to flush the network output buffer, get some
  47  * data from the network, and pass it through the telnet state
  48  * machine.  We also flush the pty input buffer (by dropping its data)
  49  * if it becomes too full.
  50  *
  51  * return 0 if OK or 1 if interrupted by a signal.
  52  */
  53
  54 int
  55 ttloop(void)
  56 {
  57     DIAG(TD_REPORT, {
  58         output_data("td: ttloop\r\n");
  59     });
  60     if (nfrontp-nbackp)
  61         netflush();
  62     ncc = read(net, netibuf, sizeof netibuf);
  63     if (ncc < 0) {
  64         if (errno == EINTR)
  65             return 1;
  66         syslog(LOG_INFO, "ttloop:  read: %m\n");
  67         exit(1);
  68     } else if (ncc == 0) {
  69         syslog(LOG_INFO, "ttloop:  peer died\n");
  70         exit(1);
  71     }
  72     DIAG(TD_REPORT, {
  73         output_data("td: ttloop read %d chars\r\n", ncc);
  74     });
  75     netip = netibuf;
  76     telrcv();                   /* state machine */
  77     if (ncc > 0) {
  78         pfrontp = pbackp = ptyobuf;
  79         telrcv();
  80     }
  81     return 0;
  82 }  /* end of ttloop */
  83
  84 /*
  85  * Check a descriptor to see if out of band data exists on it.
  86  */
  87 int
  88 stilloob(int s)
  89 {
  90     static struct timeval timeout = { 0 };
  91     fd_set      excepts;
  92     int value;
  93
  94     if (s >= FD_SETSIZE)
  95         fatal(ourpty, "fd too large");
  96
  97     do {
  98         FD_ZERO(&excepts);
  99         FD_SET(s, &excepts);
 100         value = select(s+1, 0, 0, &excepts, &timeout);
 101     } while ((value == -1) && (errno == EINTR));
 102
 103     if (value < 0) {
 104         fatalperror(ourpty, "select");
 105     }
 106     if (FD_ISSET(s, &excepts)) {
 107         return 1;
 108     } else {
 109         return 0;
 110     }
 111 }
 112
 113 void
 114 ptyflush(void)
 115 {
 116     int n;
 117
 118     if ((n = pfrontp - pbackp) > 0) {
 119         DIAG((TD_REPORT | TD_PTYDATA), {
 120             output_data("td: ptyflush %d chars\r\n", n);
 121         });
 122         DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
 123         n = write(ourpty, pbackp, n);
 124     }
 125     if (n < 0) {
 126         if (errno == EWOULDBLOCK || errno == EINTR)
 127             return;
 128         cleanup(0);
 129     }
 130     pbackp += n;
 131     if (pbackp == pfrontp)
 132         pbackp = pfrontp = ptyobuf;
 133 }
 134
 135 /*
 136  * nextitem()
 137  *
 138  *      Return the address of the next "item" in the TELNET data
 139  * stream.  This will be the address of the next character if
 140  * the current address is a user data character, or it will
 141  * be the address of the character following the TELNET command
 142  * if the current address is a TELNET IAC ("I Am a Command")
 143  * character.
 144  */
 145 char *
 146 nextitem(char *current)
 147 {
 148     if ((*current&0xff) != IAC) {
 149         return current+1;
 150     }
 151     switch (*(current+1)&0xff) {
 152     case DO:
 153     case DONT:
 154     case WILL:
 155     case WONT:
 156         return current+3;
 157     case SB:{
 158         /* loop forever looking for the SE */
 159         char *look = current+2;
 160
 161         for (;;) {
 162             if ((*look++&0xff) == IAC) {
 163                 if ((*look++&0xff) == SE) {
 164                     return look;
 165                 }
 166             }
 167         }
 168     }
 169     default:
 170         return current+2;
 171     }
 172 }
 173
 174
 175 /*
 176  * netclear()
 177  *
 178  *      We are about to do a TELNET SYNCH operation.  Clear
 179  * the path to the network.
 180  *
 181  *      Things are a bit tricky since we may have sent the first
 182  * byte or so of a previous TELNET command into the network.
 183  * So, we have to scan the network buffer from the beginning
 184  * until we are up to where we want to be.
 185  *
 186  *      A side effect of what we do, just to keep things
 187  * simple, is to clear the urgent data pointer.  The principal
 188  * caller should be setting the urgent data pointer AFTER calling
 189  * us in any case.
 190  */
 191 void
 192 netclear(void)
 193 {
 194     char *thisitem, *next;
 195     char *good;
 196 #define wewant(p)       ((nfrontp > p) && ((*p&0xff) == IAC) && \
 197                          ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
 198
 199 #ifdef ENCRYPTION
 200         thisitem = nclearto > netobuf ? nclearto : netobuf;
 201 #else
 202         thisitem = netobuf;
 203 #endif
 204
 205         while ((next = nextitem(thisitem)) <= nbackp) {
 206             thisitem = next;
 207         }
 208
 209         /* Now, thisitem is first before/at boundary. */
 210
 211 #ifdef ENCRYPTION
 212         good = nclearto > netobuf ? nclearto : netobuf;
 213 #else
 214         good = netobuf; /* where the good bytes go */
 215 #endif
 216
 217         while (nfrontp > thisitem) {
 218             if (wewant(thisitem)) {
 219                 int length;
 220
 221                 next = thisitem;
 222                 do {
 223                     next = nextitem(next);
 224                 } while (wewant(next) && (nfrontp > next));
 225                 length = next-thisitem;
 226                 memmove(good, thisitem, length);
 227                 good += length;
 228                 thisitem = next;
 229             } else {
 230                 thisitem = nextitem(thisitem);
 231             }
 232         }
 233
 234         nbackp = netobuf;
 235         nfrontp = good;         /* next byte to be sent */
 236         neturg = 0;
 237 }  /* end of netclear */
 238
 239 extern int not42;
 240
 241 /*
 242  *  netflush
 243  *              Send as much data as possible to the network,
 244  *      handling requests for urgent data.
 245  */
 246 void
 247 netflush(void)
 248 {
 249     int n;
 250
 251     if ((n = nfrontp - nbackp) > 0) {
 252         DIAG(TD_REPORT,
 253              { n += output_data("td: netflush %d chars\r\n", n);
 254              });
 255 #ifdef ENCRYPTION
 256         if (encrypt_output) {
 257             char *s = nclearto ? nclearto : nbackp;
 258             if (nfrontp - s > 0) {
 259                 (*encrypt_output)((unsigned char *)s, nfrontp-s);
 260                 nclearto = nfrontp;
 261             }
 262         }
 263 #endif
 264         /*
 265          * if no urgent data, or if the other side appears to be an
 266          * old 4.2 client (and thus unable to survive TCP urgent data),
 267          * write the entire buffer in non-OOB mode.
 268          */
 269 #if 1 /* remove this to make it work between solaris 2.6 and linux */
 270         if ((neturg == 0) || (not42 == 0)) {
 271 #endif
 272             n = write(net, nbackp, n);  /* normal write */
 273 #if 1 /* remove this to make it work between solaris 2.6 and linux */
 274         } else {
 275             n = neturg - nbackp;
 276             /*
 277              * In 4.2 (and 4.3) systems, there is some question about
 278              * what byte in a sendOOB operation is the "OOB" data.
 279              * To make ourselves compatible, we only send ONE byte
 280              * out of band, the one WE THINK should be OOB (though
 281              * we really have more the TCP philosophy of urgent data
 282              * rather than the Unix philosophy of OOB data).
 283              */
 284             if (n > 1) {
 285                 n = send(net, nbackp, n-1, 0);  /* send URGENT all by itself */
 286             } else {
 287                 n = send(net, nbackp, n, MSG_OOB);      /* URGENT data */
 288             }
 289         }
 290 #endif
 291     }
 292     if (n < 0) {
 293         if (errno == EWOULDBLOCK || errno == EINTR)
 294             return;
 295         cleanup(0);
 296     }
 297     nbackp += n;
 298 #ifdef ENCRYPTION
 299     if (nbackp > nclearto)
 300         nclearto = 0;
 301 #endif
 302     if (nbackp >= neturg) {
 303         neturg = 0;
 304     }
 305     if (nbackp == nfrontp) {
 306         nbackp = nfrontp = netobuf;
 307 #ifdef ENCRYPTION
 308         nclearto = 0;
 309 #endif
 310     }
 311     return;
 312 }
 313
 314
 315 /*
 316  * writenet
 317  *
 318  * Just a handy little function to write a bit of raw data to the net.
 319  * It will force a transmit of the buffer if necessary
 320  *
 321  * arguments
 322  *    ptr - A pointer to a character string to write
 323  *    len - How many bytes to write
 324  */
 325 void
 326 writenet(const void *ptr, size_t len)
 327 {
 328     /* flush buffer if no room for new data) */
 329     while ((&netobuf[BUFSIZ] - nfrontp) < len) {
 330         /* if this fails, don't worry, buffer is a little big */
 331         netflush();
 332     }
 333     if ((&netobuf[BUFSIZ] - nfrontp) < len)
 334         abort();
 335
 336     memmove(nfrontp, ptr, len);
 337     nfrontp += len;
 338 }
 339
 340
 341 /*
 342  * miscellaneous functions doing a variety of little jobs follow ...
 343  */
 344
 345
 346 void fatal(int f, char *msg)
 347 {
 348     char buf[BUFSIZ];
 349
 350     snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
 351 #ifdef ENCRYPTION
 352     if (encrypt_output) {
 353         /*
 354          * Better turn off encryption first....
 355          * Hope it flushes...
 356          */
 357         encrypt_send_end();
 358         netflush();
 359     }
 360 #endif
 361     write(f, buf, (int)strlen(buf));
 362     sleep(1);   /*XXX*/
 363     exit(1);
 364 }
 365
 366 void
 367 fatalperror_errno(int f, const char *msg, int error)
 368 {
 369     char buf[BUFSIZ];
 370
 371     snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(error));
 372     fatal(f, buf);
 373 }
 374
 375 void
 376 fatalperror(int f, const char *msg)
 377 {
 378     fatalperror_errno(f, msg, errno);
 379 }
 380
 381 char editedhost[32];
 382
 383 void edithost(char *pat, char *host)
 384 {
 385     char *res = editedhost;
 386
 387     if (!pat)
 388         pat = "";
 389     while (*pat) {
 390         switch (*pat) {
 391
 392         case '#':
 393             if (*host)
 394                 host++;
 395             break;
 396
 397         case '@':
 398             if (*host)
 399                 *res++ = *host++;
 400             break;
 401
 402         default:
 403             *res++ = *pat;
 404             break;
 405         }
 406         if (res == &editedhost[sizeof editedhost - 1]) {
 407             *res = '\0';
 408             return;
 409         }
 410         pat++;
 411     }
 412     if (*host)
 413         strlcpy (res, host,
 414                          sizeof editedhost - (res - editedhost));
 415     else
 416         *res = '\0';
 417     editedhost[sizeof editedhost - 1] = '\0';
 418 }
 419
 420 static char *putlocation;
 421
 422 void
 423 putstr(char *s)
 424 {
 425
 426     while (*s)
 427         putchr(*s++);
 428 }
 429
 430 void
 431 putchr(int cc)
 432 {
 433     *putlocation++ = cc;
 434 }
 435
 436 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
 437
 438 void putf(char *cp, char *where)
 439 {
 440 #ifdef HAVE_UNAME
 441     struct utsname name;
 442 #endif
 443     char *slash;
 444     time_t t;
 445     char db[100];
 446
 447     /* if we don't have uname, set these to sensible values */
 448     char *sysname = "Unix",
 449         *machine = "",
 450         *release = "",
 451         *version = "";
 452
 453 #ifdef HAVE_UNAME
 454     uname(&name);
 455     sysname=name.sysname;
 456     machine=name.machine;
 457     release=name.release;
 458     version=name.version;
 459 #endif
 460
 461     putlocation = where;
 462
 463     while (*cp) {
 464         if (*cp != '%') {
 465             putchr(*cp++);
 466             continue;
 467         }
 468         switch (*++cp) {
 469
 470         case 't':
 471             slash = strchr(line+1, '/');
 472             if (slash == (char *) 0)
 473                 putstr(line);
 474             else
 475                 putstr(&slash[1]);
 476             break;
 477
 478         case 'h':
 479             putstr(editedhost);
 480             break;
 481
 482         case 's':
 483             putstr(sysname);
 484             break;
 485
 486         case 'm':
 487             putstr(machine);
 488             break;
 489
 490         case 'r':
 491             putstr(release);
 492             break;
 493
 494         case 'v':
 495             putstr(version);
 496             break;
 497
 498         case 'd':
 499             time(&t);
 500             strftime(db, sizeof(db), fmtstr, localtime(&t));
 501             putstr(db);
 502             break;
 503
 504         case '%':
 505             putchr('%');
 506             break;
 507         }
 508         cp++;
 509     }
 510 }
 511
 512 #ifdef DIAGNOSTICS
 513 /*
 514  * Print telnet options and commands in plain text, if possible.
 515  */
 516 void
 517 printoption(char *fmt, int option)
 518 {
 519     if (TELOPT_OK(option))
 520         output_data("%s %s\r\n",
 521                     fmt,
 522                     TELOPT(option));
 523     else if (TELCMD_OK(option))
 524         output_data("%s %s\r\n",
 525                     fmt,
 526                     TELCMD(option));
 527     else
 528         output_data("%s %d\r\n",
 529                     fmt,
 530                     option);
 531     return;
 532 }
 533
 534 void
 535 printsub(int direction, unsigned char *pointer, int length)
 536                                         /* '<' or '>' */
 537                                         /* where suboption data sits */
 538                                         /* length of suboption data */
 539 {
 540     int i = 0;
 541     unsigned char buf[512];
 542
 543     if (!(diagnostic & TD_OPTIONS))
 544         return;
 545
 546     if (direction) {
 547         output_data("td: %s suboption ",
 548                     direction == '<' ? "recv" : "send");
 549         if (length >= 3) {
 550             int j;
 551
 552             i = pointer[length-2];
 553             j = pointer[length-1];
 554
 555             if (i != IAC || j != SE) {
 556                 output_data("(terminated by ");
 557                 if (TELOPT_OK(i))
 558                     output_data("%s ",
 559                                 TELOPT(i));
 560                 else if (TELCMD_OK(i))
 561                     output_data("%s ",
 562                                 TELCMD(i));
 563                 else
 564                     output_data("%d ",
 565                                 i);
 566                 if (TELOPT_OK(j))
 567                     output_data("%s",
 568                                 TELOPT(j));
 569                 else if (TELCMD_OK(j))
 570                     output_data("%s",
 571                                 TELCMD(j));
 572                 else
 573                     output_data("%d",
 574                                 j);
 575                 output_data(", not IAC SE!) ");
 576             }
 577         }
 578         length -= 2;
 579     }
 580     if (length < 1) {
 581         output_data("(Empty suboption??\?)");
 582         return;
 583     }
 584     switch (pointer[0]) {
 585     case TELOPT_TTYPE:
 586         output_data("TERMINAL-TYPE ");
 587         switch (pointer[1]) {
 588         case TELQUAL_IS:
 589             output_data("IS \"%.*s\"",
 590                         length-2,
 591                         (char *)pointer+2);
 592             break;
 593         case TELQUAL_SEND:
 594             output_data("SEND");
 595             break;
 596         default:
 597             output_data("- unknown qualifier %d (0x%x).",
 598                         pointer[1], pointer[1]);
 599         }
 600         break;
 601     case TELOPT_TSPEED:
 602         output_data("TERMINAL-SPEED");
 603         if (length < 2) {
 604             output_data(" (empty suboption??\?)");
 605             break;
 606         }
 607         switch (pointer[1]) {
 608         case TELQUAL_IS:
 609             output_data(" IS %.*s", length-2, (char *)pointer+2);
 610             break;
 611         default:
 612             if (pointer[1] == 1)
 613                 output_data(" SEND");
 614             else
 615                 output_data(" %d (unknown)", pointer[1]);
 616             for (i = 2; i < length; i++) {
 617                 output_data(" ?%d?", pointer[i]);
 618             }
 619             break;
 620         }
 621         break;
 622
 623     case TELOPT_LFLOW:
 624         output_data("TOGGLE-FLOW-CONTROL");
 625         if (length < 2) {
 626             output_data(" (empty suboption??\?)");
 627             break;
 628         }
 629         switch (pointer[1]) {
 630         case LFLOW_OFF:
 631             output_data(" OFF");
 632             break;
 633         case LFLOW_ON:
 634             output_data(" ON");
 635             break;
 636         case LFLOW_RESTART_ANY:
 637             output_data(" RESTART-ANY");
 638             break;
 639         case LFLOW_RESTART_XON:
 640             output_data(" RESTART-XON");
 641             break;
 642         default:
 643             output_data(" %d (unknown)",
 644                         pointer[1]);
 645         }
 646         for (i = 2; i < length; i++) {
 647             output_data(" ?%d?",
 648                         pointer[i]);
 649         }
 650         break;
 651
 652     case TELOPT_NAWS:
 653         output_data("NAWS");
 654         if (length < 2) {
 655             output_data(" (empty suboption??\?)");
 656             break;
 657         }
 658         if (length == 2) {
 659             output_data(" ?%d?",
 660                         pointer[1]);
 661             break;
 662         }
 663         output_data(" %u %u(%u)",
 664                     pointer[1],
 665                     pointer[2],
 666                     (((unsigned int)pointer[1])<<8) + pointer[2]);
 667         if (length == 4) {
 668             output_data(" ?%d?",
 669                         pointer[3]);
 670             break;
 671         }
 672         output_data(" %u %u(%u)",
 673                     pointer[3],
 674                     pointer[4],
 675                     (((unsigned int)pointer[3])<<8) + pointer[4]);
 676         for (i = 5; i < length; i++) {
 677             output_data(" ?%d?",
 678                         pointer[i]);
 679         }
 680         break;
 681
 682     case TELOPT_LINEMODE:
 683         output_data("LINEMODE ");
 684         if (length < 2) {
 685             output_data(" (empty suboption??\?)");
 686             break;
 687         }
 688         switch (pointer[1]) {
 689         case WILL:
 690             output_data("WILL ");
 691             goto common;
 692         case WONT:
 693             output_data("WONT ");
 694             goto common;
 695         case DO:
 696             output_data("DO ");
 697             goto common;
 698         case DONT:
 699             output_data("DONT ");
 700         common:
 701             if (length < 3) {
 702                 output_data("(no option??\?)");
 703                 break;
 704             }
 705             switch (pointer[2]) {
 706             case LM_FORWARDMASK:
 707                 output_data("Forward Mask");
 708                 for (i = 3; i < length; i++) {
 709                     output_data(" %x", pointer[i]);
 710                 }
 711                 break;
 712             default:
 713                 output_data("%d (unknown)",
 714                             pointer[2]);
 715                 for (i = 3; i < length; i++) {
 716                     output_data(" %d",
 717                                 pointer[i]);
 718                 }
 719                 break;
 720             }
 721             break;
 722
 723         case LM_SLC:
 724             output_data("SLC");
 725             for (i = 2; i < length - 2; i += 3) {
 726                 if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
 727                     output_data(" %s",
 728                                 SLC_NAME(pointer[i+SLC_FUNC]));
 729                 else
 730                     output_data(" %d",
 731                                 pointer[i+SLC_FUNC]);
 732                 switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
 733                 case SLC_NOSUPPORT:
 734                     output_data(" NOSUPPORT");
 735                     break;
 736                 case SLC_CANTCHANGE:
 737                     output_data(" CANTCHANGE");
 738                     break;
 739                 case SLC_VARIABLE:
 740                     output_data(" VARIABLE");
 741                     break;
 742                 case SLC_DEFAULT:
 743                     output_data(" DEFAULT");
 744                     break;
 745                 }
 746                 output_data("%s%s%s",
 747                             pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
 748                             pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
 749                             pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
 750                 if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
 751                                             SLC_FLUSHOUT| SLC_LEVELBITS)) {
 752                     output_data("(0x%x)",
 753                                 pointer[i+SLC_FLAGS]);
 754                 }
 755                 output_data(" %d;",
 756                             pointer[i+SLC_VALUE]);
 757                 if ((pointer[i+SLC_VALUE] == IAC) &&
 758                     (pointer[i+SLC_VALUE+1] == IAC))
 759                     i++;
 760             }
 761             for (; i < length; i++) {
 762                 output_data(" ?%d?",
 763                             pointer[i]);
 764             }
 765             break;
 766
 767         case LM_MODE:
 768             output_data("MODE ");
 769             if (length < 3) {
 770                 output_data("(no mode??\?)");
 771                 break;
 772             }
 773             {
 774                 char tbuf[32];
 775                 snprintf(tbuf,
 776                          sizeof(tbuf),
 777                          "%s%s%s%s%s",
 778                          pointer[2]&MODE_EDIT ? "|EDIT" : "",
 779                          pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
 780                          pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
 781                          pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
 782                          pointer[2]&MODE_ACK ? "|ACK" : "");
 783                 output_data("%s",
 784                             tbuf[1] ? &tbuf[1] : "0");
 785             }
 786             if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
 787                 output_data(" (0x%x)",
 788                             pointer[2]);
 789             }
 790             for (i = 3; i < length; i++) {
 791                 output_data(" ?0x%x?",
 792                          pointer[i]);
 793             }
 794             break;
 795         default:
 796             output_data("%d (unknown)",
 797                         pointer[1]);
 798             for (i = 2; i < length; i++) {
 799                 output_data(" %d", pointer[i]);
 800             }
 801         }
 802         break;
 803
 804     case TELOPT_STATUS: {
 805         char *cp;
 806         int j, k;
 807
 808         output_data("STATUS");
 809
 810         switch (pointer[1]) {
 811         default:
 812             if (pointer[1] == TELQUAL_SEND)
 813                 output_data(" SEND");
 814             else
 815                 output_data(" %d (unknown)",
 816                             pointer[1]);
 817             for (i = 2; i < length; i++) {
 818                 output_data(" ?%d?",
 819                             pointer[i]);
 820             }
 821             break;
 822         case TELQUAL_IS:
 823             output_data(" IS\r\n");
 824
 825             for (i = 2; i < length; i++) {
 826                 switch(pointer[i]) {
 827                 case DO:        cp = "DO"; goto common2;
 828                 case DONT:      cp = "DONT"; goto common2;
 829                 case WILL:      cp = "WILL"; goto common2;
 830                 case WONT:      cp = "WONT"; goto common2;
 831                 common2:
 832                 i++;
 833                 if (TELOPT_OK(pointer[i]))
 834                     output_data(" %s %s",
 835                                 cp,
 836                                 TELOPT(pointer[i]));
 837                 else
 838                     output_data(" %s %d",
 839                                 cp,
 840                                 pointer[i]);
 841
 842                 output_data("\r\n");
 843                 break;
 844
 845                 case SB:
 846                     output_data(" SB ");
 847                     i++;
 848                     j = k = i;
 849                     while (j < length) {
 850                         if (pointer[j] == SE) {
 851                             if (j+1 == length)
 852                                 break;
 853                             if (pointer[j+1] == SE)
 854                                 j++;
 855                             else
 856                                 break;
 857                         }
 858                         pointer[k++] = pointer[j++];
 859                     }
 860                     printsub(0, &pointer[i], k - i);
 861                     if (i < length) {
 862                         output_data(" SE");
 863                         i = j;
 864                     } else
 865                         i = j - 1;
 866
 867                     output_data("\r\n");
 868
 869                     break;
 870
 871                 default:
 872                     output_data(" %d",
 873                                 pointer[i]);
 874                     break;
 875                 }
 876             }
 877             break;
 878         }
 879         break;
 880     }
 881
 882     case TELOPT_XDISPLOC:
 883         output_data("X-DISPLAY-LOCATION ");
 884         switch (pointer[1]) {
 885         case TELQUAL_IS:
 886             output_data("IS \"%.*s\"",
 887                         length-2,
 888                         (char *)pointer+2);
 889             break;
 890         case TELQUAL_SEND:
 891             output_data("SEND");
 892             break;
 893         default:
 894             output_data("- unknown qualifier %d (0x%x).",
 895                         pointer[1], pointer[1]);
 896         }
 897         break;
 898
 899     case TELOPT_NEW_ENVIRON:
 900         output_data("NEW-ENVIRON ");
 901         goto env_common1;
 902     case TELOPT_OLD_ENVIRON:
 903         output_data("OLD-ENVIRON");
 904     env_common1:
 905         switch (pointer[1]) {
 906         case TELQUAL_IS:
 907             output_data("IS ");
 908             goto env_common;
 909         case TELQUAL_SEND:
 910             output_data("SEND ");
 911             goto env_common;
 912         case TELQUAL_INFO:
 913             output_data("INFO ");
 914         env_common:
 915             {
 916                 int noquote = 2;
 917                 for (i = 2; i < length; i++ ) {
 918                     switch (pointer[i]) {
 919                     case NEW_ENV_VAR:
 920                         output_data("\" VAR " + noquote);
 921                         noquote = 2;
 922                         break;
 923
 924                     case NEW_ENV_VALUE:
 925                         output_data("\" VALUE " + noquote);
 926                         noquote = 2;
 927                         break;
 928
 929                     case ENV_ESC:
 930                         output_data("\" ESC " + noquote);
 931                         noquote = 2;
 932                         break;
 933
 934                     case ENV_USERVAR:
 935                         output_data("\" USERVAR " + noquote);
 936                         noquote = 2;
 937                         break;
 938
 939                     default:
 940                         if (isprint(pointer[i]) && pointer[i] != '"') {
 941                             if (noquote) {
 942                                 output_data ("\"");
 943                                 noquote = 0;
 944                             }
 945                             output_data ("%c", pointer[i]);
 946                         } else {
 947                             output_data("\" %03o " + noquote,
 948                                         pointer[i]);
 949                             noquote = 2;
 950                         }
 951                         break;
 952                     }
 953                 }
 954                 if (!noquote)
 955                     output_data ("\"");
 956                 break;
 957             }
 958         }
 959         break;
 960
 961 #ifdef AUTHENTICATION
 962     case TELOPT_AUTHENTICATION:
 963         output_data("AUTHENTICATION");
 964
 965         if (length < 2) {
 966             output_data(" (empty suboption??\?)");
 967             break;
 968         }
 969         switch (pointer[1]) {
 970         case TELQUAL_REPLY:
 971         case TELQUAL_IS:
 972             output_data(" %s ",
 973                         (pointer[1] == TELQUAL_IS) ?
 974                         "IS" : "REPLY");
 975             if (AUTHTYPE_NAME_OK(pointer[2]))
 976                 output_data("%s ",
 977                             AUTHTYPE_NAME(pointer[2]));
 978             else
 979                 output_data("%d ",
 980                             pointer[2]);
 981             if (length < 3) {
 982                 output_data("(partial suboption??\?)");
 983                 break;
 984             }
 985             output_data("%s|%s",
 986                         ((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
 987                         "CLIENT" : "SERVER",
 988                         ((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
 989                         "MUTUAL" : "ONE-WAY");
 990
 991             auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
 992             output_data("%s",
 993                         buf);
 994             break;
 995
 996         case TELQUAL_SEND:
 997             i = 2;
 998             output_data(" SEND ");
 999             while (i < length) {
1000                 if (AUTHTYPE_NAME_OK(pointer[i]))
1001                     output_data("%s ",
1002                                 AUTHTYPE_NAME(pointer[i]));
1003                 else
1004                     output_data("%d ",
1005                                 pointer[i]);
1006                 if (++i >= length) {
1007                     output_data("(partial suboption??\?)");
1008                     break;
1009                 }
1010                 output_data("%s|%s ",
1011                             ((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
1012                             "CLIENT" : "SERVER",
1013                             ((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
1014                             "MUTUAL" : "ONE-WAY");
1015                 ++i;
1016             }
1017             break;
1018
1019         case TELQUAL_NAME:
1020             i = 2;
1021             output_data(" NAME \"%.*s\"",
1022                         length - 2,
1023                         pointer);
1024             break;
1025
1026         default:
1027             for (i = 2; i < length; i++) {
1028                 output_data(" ?%d?",
1029                             pointer[i]);
1030             }
1031             break;
1032         }
1033         break;
1034 #endif
1035
1036 #ifdef ENCRYPTION
1037     case TELOPT_ENCRYPT:
1038         output_data("ENCRYPT");
1039         if (length < 2) {
1040             output_data(" (empty suboption?)");
1041             break;
1042         }
1043         switch (pointer[1]) {
1044         case ENCRYPT_START:
1045             output_data(" START");
1046             break;
1047
1048         case ENCRYPT_END:
1049             output_data(" END");
1050             break;
1051
1052         case ENCRYPT_REQSTART:
1053             output_data(" REQUEST-START");
1054             break;
1055
1056         case ENCRYPT_REQEND:
1057             output_data(" REQUEST-END");
1058             break;
1059
1060         case ENCRYPT_IS:
1061         case ENCRYPT_REPLY:
1062             output_data(" %s ",
1063                         (pointer[1] == ENCRYPT_IS) ?
1064                         "IS" : "REPLY");
1065             if (length < 3) {
1066                 output_data(" (partial suboption?)");
1067                 break;
1068             }
1069             if (ENCTYPE_NAME_OK(pointer[2]))
1070                 output_data("%s ",
1071                             ENCTYPE_NAME(pointer[2]));
1072             else
1073                 output_data(" %d (unknown)",
1074                             pointer[2]);
1075
1076             encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
1077             output_data("%s",
1078                         buf);
1079             break;
1080
1081         case ENCRYPT_SUPPORT:
1082             i = 2;
1083             output_data(" SUPPORT ");
1084             while (i < length) {
1085                 if (ENCTYPE_NAME_OK(pointer[i]))
1086                     output_data("%s ",
1087                                 ENCTYPE_NAME(pointer[i]));
1088                 else
1089                     output_data("%d ",
1090                                 pointer[i]);
1091                 i++;
1092             }
1093             break;
1094
1095         case ENCRYPT_ENC_KEYID:
1096             output_data(" ENC_KEYID %d", pointer[1]);
1097             goto encommon;
1098
1099         case ENCRYPT_DEC_KEYID:
1100             output_data(" DEC_KEYID %d", pointer[1]);
1101             goto encommon;
1102
1103         default:
1104             output_data(" %d (unknown)", pointer[1]);
1105         encommon:
1106             for (i = 2; i < length; i++) {
1107                 output_data(" %d", pointer[i]);
1108             }
1109             break;
1110         }
1111         break;
1112 #endif
1113
1114     default:
1115         if (TELOPT_OK(pointer[0]))
1116             output_data("%s (unknown)",
1117                         TELOPT(pointer[0]));
1118         else
1119             output_data("%d (unknown)",
1120                         pointer[i]);
1121         for (i = 1; i < length; i++) {
1122             output_data(" %d", pointer[i]);
1123         }
1124         break;
1125     }
1126     output_data("\r\n");
1127 }
1128
1129 /*
1130  * Dump a data buffer in hex and ascii to the output data stream.
1131  */
1132 void
1133 printdata(char *tag, char *ptr, int cnt)
1134 {
1135     int i;
1136     char xbuf[30];
1137
1138     while (cnt) {
1139         /* flush net output buffer if no room for new data) */
1140         if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1141             netflush();
1142         }
1143
1144         /* add a line of output */
1145         output_data("%s: ", tag);
1146         for (i = 0; i < 20 && cnt; i++) {
1147             output_data("%02x", *ptr);
1148             if (isprint((unsigned char)*ptr)) {
1149                 xbuf[i] = *ptr;
1150             } else {
1151                 xbuf[i] = '.';
1152             }
1153             if (i % 2) {
1154                 output_data(" ");
1155             }
1156             cnt--;
1157             ptr++;
1158         }
1159         xbuf[i] = '\0';
1160         output_data(" %s\r\n", xbuf);
1161     }
1162 }
1163 #endif /* DIAGNOSTICS */