crypto/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 #ifndef lint
  35 #if 0
  36 static const char sccsid[] = "@(#)utility.c     8.4 (Berkeley) 5/30/95";
  37 #endif
  38 static const char rcsid[] =
  39   "$FreeBSD: src/crypto/telnet/telnetd/utility.c,v 1.5.2.4 2002/04/13 10:59:09 markm Exp $";
  40 #endif /* not lint */
  41
  42 #ifdef __FreeBSD__
  43 #include <locale.h>
  44 #include <sys/utsname.h>
  45 #endif
  46 #include <string.h>
  47 #define PRINTOPTIONS
  48 #include "telnetd.h"
  49
  50 #ifdef  AUTHENTICATION
  51 #include <libtelnet/auth.h>
  52 #endif
  53 #ifdef  ENCRYPTION
  54 #include <libtelnet/encrypt.h>
  55 #endif
  56
  57 /*
  58  * utility functions performing io related tasks
  59  */
  60
  61 /*
  62  * ttloop
  63  *
  64  *      A small subroutine to flush the network output buffer, get some data
  65  * from the network, and pass it through the telnet state machine.  We
  66  * also flush the pty input buffer (by dropping its data) if it becomes
  67  * too full.
  68  */
  69
  70     void
  71 ttloop()
  72 {
  73
  74     DIAG(TD_REPORT, output_data("td: ttloop\r\n"));
  75     if (nfrontp - nbackp > 0) {
  76         netflush();
  77     }
  78     ncc = read(net, netibuf, sizeof netibuf);
  79     if (ncc < 0) {
  80         syslog(LOG_INFO, "ttloop:  read: %m");
  81         exit(1);
  82     } else if (ncc == 0) {
  83         syslog(LOG_INFO, "ttloop:  peer died: %m");
  84         exit(1);
  85     }
  86     DIAG(TD_REPORT, output_data("td: ttloop read %d chars\r\n", ncc));
  87     netip = netibuf;
  88     telrcv();                   /* state machine */
  89     if (ncc > 0) {
  90         pfrontp = pbackp = ptyobuf;
  91         telrcv();
  92     }
  93 }  /* end of ttloop */
  94
  95 /*
  96  * Check a descriptor to see if out of band data exists on it.
  97  */
  98 int
  99 stilloob(int s)
 100 {
 101     static struct timeval timeout = { 0, 0 };
 102     fd_set      excepts;
 103     int value;
 104
 105     do {
 106         FD_ZERO(&excepts);
 107         FD_SET(s, &excepts);
 108         memset((char *)&timeout, 0, sizeof timeout);
 109         value = select(s+1, (fd_set *)0, (fd_set *)0, &excepts, &timeout);
 110     } while ((value == -1) && (errno == EINTR));
 111
 112     if (value < 0) {
 113         fatalperror(pty, "select");
 114     }
 115     if (FD_ISSET(s, &excepts)) {
 116         return 1;
 117     } else {
 118         return 0;
 119     }
 120 }
 121
 122 void
 123 ptyflush(void)
 124 {
 125         int n;
 126
 127         if ((n = pfrontp - pbackp) > 0) {
 128                 DIAG(TD_REPORT | TD_PTYDATA,
 129                     output_data("td: ptyflush %d chars\r\n", n));
 130                 DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
 131                 n = write(pty, pbackp, n);
 132         }
 133         if (n < 0) {
 134                 if (errno == EWOULDBLOCK || errno == EINTR)
 135                         return;
 136                 cleanup(0);
 137         }
 138         pbackp += n;
 139         if (pbackp == pfrontp)
 140                 pbackp = pfrontp = ptyobuf;
 141 }
 142
 143 /*
 144  * nextitem()
 145  *
 146  *      Return the address of the next "item" in the TELNET data
 147  * stream.  This will be the address of the next character if
 148  * the current address is a user data character, or it will
 149  * be the address of the character following the TELNET command
 150  * if the current address is a TELNET IAC ("I Am a Command")
 151  * character.
 152  */
 153 static char *
 154 nextitem(char *current)
 155 {
 156     if ((*current&0xff) != IAC) {
 157         return current+1;
 158     }
 159     switch (*(current+1)&0xff) {
 160     case DO:
 161     case DONT:
 162     case WILL:
 163     case WONT:
 164         return current+3;
 165     case SB:            /* loop forever looking for the SE */
 166         {
 167             char *look = current+2;
 168
 169             for (;;) {
 170                 if ((*look++&0xff) == IAC) {
 171                     if ((*look++&0xff) == SE) {
 172                         return look;
 173                     }
 174                 }
 175             }
 176         }
 177     default:
 178         return current+2;
 179     }
 180 }  /* end of nextitem */
 181
 182 /*
 183  * netclear()
 184  *
 185  *      We are about to do a TELNET SYNCH operation.  Clear
 186  * the path to the network.
 187  *
 188  *      Things are a bit tricky since we may have sent the first
 189  * byte or so of a previous TELNET command into the network.
 190  * So, we have to scan the network buffer from the beginning
 191  * until we are up to where we want to be.
 192  *
 193  *      A side effect of what we do, just to keep things
 194  * simple, is to clear the urgent data pointer.  The principal
 195  * caller should be setting the urgent data pointer AFTER calling
 196  * us in any case.
 197  */
 198 void
 199 netclear(void)
 200 {
 201     char *thisitem, *next;
 202     char *good;
 203 #define wewant(p)       ((nfrontp > p) && ((*p&0xff) == IAC) && \
 204                                 ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
 205
 206 #ifdef  ENCRYPTION
 207     thisitem = nclearto > netobuf ? nclearto : netobuf;
 208 #else   /* ENCRYPTION */
 209     thisitem = netobuf;
 210 #endif  /* ENCRYPTION */
 211
 212     while ((next = nextitem(thisitem)) <= nbackp) {
 213         thisitem = next;
 214     }
 215
 216     /* Now, thisitem is first before/at boundary. */
 217
 218 #ifdef  ENCRYPTION
 219     good = nclearto > netobuf ? nclearto : netobuf;
 220 #else   /* ENCRYPTION */
 221     good = netobuf;     /* where the good bytes go */
 222 #endif  /* ENCRYPTION */
 223
 224     while (nfrontp > thisitem) {
 225         if (wewant(thisitem)) {
 226             int length;
 227
 228             next = thisitem;
 229             do {
 230                 next = nextitem(next);
 231             } while (wewant(next) && (nfrontp > next));
 232             length = next-thisitem;
 233             memmove(good, thisitem, length);
 234             good += length;
 235             thisitem = next;
 236         } else {
 237             thisitem = nextitem(thisitem);
 238         }
 239     }
 240
 241     nbackp = netobuf;
 242     nfrontp = good;             /* next byte to be sent */
 243     neturg = 0;
 244 }  /* end of netclear */
 245
 246 /*
 247  *  netflush
 248  *              Send as much data as possible to the network,
 249  *      handling requests for urgent data.
 250  */
 251 void
 252 netflush(void)
 253 {
 254     int n;
 255     extern int not42;
 256
 257     while ((n = nfrontp - nbackp) > 0) {
 258 #if 0
 259         /* XXX This causes output_data() to recurse and die */
 260         DIAG(TD_REPORT, {
 261             n += output_data("td: netflush %d chars\r\n", n);
 262         });
 263 #endif
 264 #ifdef  ENCRYPTION
 265         if (encrypt_output) {
 266                 char *s = nclearto ? nclearto : nbackp;
 267                 if (nfrontp - s > 0) {
 268                         (*encrypt_output)((unsigned char *)s, nfrontp-s);
 269                         nclearto = nfrontp;
 270                 }
 271         }
 272 #endif  /* ENCRYPTION */
 273         /*
 274          * if no urgent data, or if the other side appears to be an
 275          * old 4.2 client (and thus unable to survive TCP urgent data),
 276          * write the entire buffer in non-OOB mode.
 277          */
 278         if ((neturg == 0) || (not42 == 0)) {
 279             n = write(net, nbackp, n);  /* normal write */
 280         } else {
 281             n = neturg - nbackp;
 282             /*
 283              * In 4.2 (and 4.3) systems, there is some question about
 284              * what byte in a sendOOB operation is the "OOB" data.
 285              * To make ourselves compatible, we only send ONE byte
 286              * out of band, the one WE THINK should be OOB (though
 287              * we really have more the TCP philosophy of urgent data
 288              * rather than the Unix philosophy of OOB data).
 289              */
 290             if (n > 1) {
 291                 n = send(net, nbackp, n-1, 0);  /* send URGENT all by itself */
 292             } else {
 293                 n = send(net, nbackp, n, MSG_OOB);      /* URGENT data */
 294             }
 295         }
 296         if (n == -1) {
 297             if (errno == EWOULDBLOCK || errno == EINTR)
 298                 continue;
 299             cleanup(0);
 300             /* NOTREACHED */
 301         }
 302         nbackp += n;
 303 #ifdef  ENCRYPTION
 304         if (nbackp > nclearto)
 305             nclearto = 0;
 306 #endif  /* ENCRYPTION */
 307         if (nbackp >= neturg) {
 308             neturg = 0;
 309         }
 310         if (nbackp == nfrontp) {
 311             nbackp = nfrontp = netobuf;
 312 #ifdef  ENCRYPTION
 313             nclearto = 0;
 314 #endif  /* ENCRYPTION */
 315         }
 316     }
 317     return;
 318 }  /* end of netflush */
 319
 320
 321 /*
 322  * miscellaneous functions doing a variety of little jobs follow ...
 323  */
 324
 325
 326 void
 327 fatal(int f, const char *msg)
 328 {
 329         char buf[BUFSIZ];
 330
 331         (void) snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
 332 #ifdef  ENCRYPTION
 333         if (encrypt_output) {
 334                 /*
 335                  * Better turn off encryption first....
 336                  * Hope it flushes...
 337                  */
 338                 encrypt_send_end();
 339                 netflush();
 340         }
 341 #endif  /* ENCRYPTION */
 342         (void) write(f, buf, (int)strlen(buf));
 343         sleep(1);       /*XXX*/
 344         exit(1);
 345 }
 346
 347 void
 348 fatalperror(int f, const char *msg)
 349 {
 350         char buf[BUFSIZ];
 351
 352         (void) snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(errno));
 353         fatal(f, buf);
 354 }
 355
 356 char editedhost[32];
 357
 358 void
 359 edithost(char *pat, char *host)
 360 {
 361         char *res = editedhost;
 362
 363         if (!pat)
 364                 pat = strdup("");
 365         while (*pat) {
 366                 switch (*pat) {
 367
 368                 case '#':
 369                         if (*host)
 370                                 host++;
 371                         break;
 372
 373                 case '@':
 374                         if (*host)
 375                                 *res++ = *host++;
 376                         break;
 377
 378                 default:
 379                         *res++ = *pat;
 380                         break;
 381                 }
 382                 if (res == &editedhost[sizeof editedhost - 1]) {
 383                         *res = '\0';
 384                         return;
 385                 }
 386                 pat++;
 387         }
 388         if (*host)
 389                 (void) strncpy(res, host,
 390                                 sizeof editedhost - (res - editedhost) -1);
 391         else
 392                 *res = '\0';
 393         editedhost[sizeof editedhost - 1] = '\0';
 394 }
 395
 396 static char *putlocation;
 397
 398 static void
 399 putstr(const char *s)
 400 {
 401
 402         while (*s)
 403                 putchr(*s++);
 404 }
 405
 406 void
 407 putchr(int cc)
 408 {
 409         *putlocation++ = cc;
 410 }
 411
 412 #ifdef __FreeBSD__
 413 static char fmtstr[] = { "%+" };
 414 #else
 415 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
 416 #endif
 417
 418 void
 419 putf(char *cp, char *where)
 420 {
 421         char *slash;
 422         time_t t;
 423         char db[100];
 424 #ifdef __FreeBSD__
 425         static struct utsname kerninfo;
 426
 427         if (!*kerninfo.sysname)
 428                 uname(&kerninfo);
 429 #endif
 430
 431         putlocation = where;
 432
 433         while (*cp) {
 434                 if (*cp =='\n') {
 435                         putstr("\r\n");
 436                         cp++;
 437                         continue;
 438                 } else if (*cp != '%') {
 439                         putchr(*cp++);
 440                         continue;
 441                 }
 442                 switch (*++cp) {
 443
 444                 case 't':
 445 #ifdef  STREAMSPTY
 446                         /* names are like /dev/pts/2 -- we want pts/2 */
 447                         slash = strchr(line+1, '/');
 448 #else
 449                         slash = strrchr(line, '/');
 450 #endif
 451                         if (slash == (char *) 0)
 452                                 putstr(line);
 453                         else
 454                                 putstr(&slash[1]);
 455                         break;
 456
 457                 case 'h':
 458                         putstr(editedhost);
 459                         break;
 460
 461                 case 'd':
 462 #ifdef __FreeBSD__
 463                         setlocale(LC_TIME, "");
 464 #endif
 465                         (void)time(&t);
 466                         (void)strftime(db, sizeof(db), fmtstr, localtime(&t));
 467                         putstr(db);
 468                         break;
 469
 470 #ifdef __FreeBSD__
 471                 case 's':
 472                         putstr(kerninfo.sysname);
 473                         break;
 474
 475                 case 'm':
 476                         putstr(kerninfo.machine);
 477                         break;
 478
 479                 case 'r':
 480                         putstr(kerninfo.release);
 481                         break;
 482
 483                 case 'v':
 484                         putstr(kerninfo.version);
 485                         break;
 486 #endif
 487
 488                 case '%':
 489                         putchr('%');
 490                         break;
 491                 }
 492                 cp++;
 493         }
 494 }
 495
 496 #ifdef DIAGNOSTICS
 497 /*
 498  * Print telnet options and commands in plain text, if possible.
 499  */
 500 void
 501 printoption(const char *fmt, int option)
 502 {
 503         if (TELOPT_OK(option))
 504                 output_data("%s %s\r\n", fmt, TELOPT(option));
 505         else if (TELCMD_OK(option))
 506                 output_data("%s %s\r\n", fmt, TELCMD(option));
 507         else
 508                 output_data("%s %d\r\n", fmt, option);
 509         return;
 510 }
 511
 512 void
 513 printsub(char direction, unsigned char *pointer, int length)
 514 {
 515     int i = 0;
 516
 517         if (!(diagnostic & TD_OPTIONS))
 518                 return;
 519
 520         if (direction) {
 521             output_data("td: %s suboption ",
 522                                         direction == '<' ? "recv" : "send");
 523             if (length >= 3) {
 524                 int j;
 525
 526                 i = pointer[length-2];
 527                 j = pointer[length-1];
 528
 529                 if (i != IAC || j != SE) {
 530                     output_data("(terminated by ");
 531                     if (TELOPT_OK(i))
 532                         output_data("%s ", TELOPT(i));
 533                     else if (TELCMD_OK(i))
 534                         output_data("%s ", TELCMD(i));
 535                     else
 536                         output_data("%d ", i);
 537                     if (TELOPT_OK(j))
 538                         output_data("%s", TELOPT(j));
 539                     else if (TELCMD_OK(j))
 540                         output_data("%s", TELCMD(j));
 541                     else
 542                         output_data("%d", j);
 543                     output_data(", not IAC SE!) ");
 544                 }
 545             }
 546             length -= 2;
 547         }
 548         if (length < 1) {
 549             output_data("(Empty suboption??\?)");
 550             return;
 551         }
 552         switch (pointer[0]) {
 553         case TELOPT_TTYPE:
 554             output_data("TERMINAL-TYPE ");
 555             switch (pointer[1]) {
 556             case TELQUAL_IS:
 557                 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
 558                 break;
 559             case TELQUAL_SEND:
 560                 output_data("SEND");
 561                 break;
 562             default:
 563                 output_data(
 564                                 "- unknown qualifier %d (0x%x).",
 565                                 pointer[1], pointer[1]);
 566             }
 567             break;
 568         case TELOPT_TSPEED:
 569             output_data("TERMINAL-SPEED");
 570             if (length < 2) {
 571                 output_data(" (empty suboption??\?)");
 572                 break;
 573             }
 574             switch (pointer[1]) {
 575             case TELQUAL_IS:
 576                 output_data(" IS %.*s", length-2, (char *)pointer+2);
 577                 break;
 578             default:
 579                 if (pointer[1] == 1)
 580                     output_data(" SEND");
 581                 else
 582                     output_data(" %d (unknown)", pointer[1]);
 583                 for (i = 2; i < length; i++) {
 584                     output_data(" ?%d?", pointer[i]);
 585                 }
 586                 break;
 587             }
 588             break;
 589
 590         case TELOPT_LFLOW:
 591             output_data("TOGGLE-FLOW-CONTROL");
 592             if (length < 2) {
 593                 output_data(" (empty suboption??\?)");
 594                 break;
 595             }
 596             switch (pointer[1]) {
 597             case LFLOW_OFF:
 598                 output_data(" OFF"); break;
 599             case LFLOW_ON:
 600                 output_data(" ON"); break;
 601             case LFLOW_RESTART_ANY:
 602                 output_data(" RESTART-ANY"); break;
 603             case LFLOW_RESTART_XON:
 604                 output_data(" RESTART-XON"); break;
 605             default:
 606                 output_data(" %d (unknown)", pointer[1]);
 607             }
 608             for (i = 2; i < length; i++) {
 609                 output_data(" ?%d?", pointer[i]);
 610             }
 611             break;
 612
 613         case TELOPT_NAWS:
 614             output_data("NAWS");
 615             if (length < 2) {
 616                 output_data(" (empty suboption??\?)");
 617                 break;
 618             }
 619             if (length == 2) {
 620                 output_data(" ?%d?", pointer[1]);
 621                 break;
 622             }
 623             output_data(" %d %d (%d)",
 624                 pointer[1], pointer[2],
 625                 (int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
 626             if (length == 4) {
 627                 output_data(" ?%d?", pointer[3]);
 628                 break;
 629             }
 630             output_data(" %d %d (%d)",
 631                 pointer[3], pointer[4],
 632                 (int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
 633             for (i = 5; i < length; i++) {
 634                 output_data(" ?%d?", pointer[i]);
 635             }
 636             break;
 637
 638         case TELOPT_LINEMODE:
 639             output_data("LINEMODE ");
 640             if (length < 2) {
 641                 output_data(" (empty suboption??\?)");
 642                 break;
 643             }
 644             switch (pointer[1]) {
 645             case WILL:
 646                 output_data("WILL ");
 647                 goto common;
 648             case WONT:
 649                 output_data("WONT ");
 650                 goto common;
 651             case DO:
 652                 output_data("DO ");
 653                 goto common;
 654             case DONT:
 655                 output_data("DONT ");
 656             common:
 657                 if (length < 3) {
 658                     output_data("(no option??\?)");
 659                     break;
 660                 }
 661                 switch (pointer[2]) {
 662                 case LM_FORWARDMASK:
 663                     output_data("Forward Mask");
 664                     for (i = 3; i < length; i++) {
 665                         output_data(" %x", pointer[i]);
 666                     }
 667                     break;
 668                 default:
 669                     output_data("%d (unknown)", pointer[2]);
 670                     for (i = 3; i < length; i++) {
 671                         output_data(" %d", pointer[i]);
 672                     }
 673                     break;
 674                 }
 675                 break;
 676
 677             case LM_SLC:
 678                 output_data("SLC");
 679                 for (i = 2; i < length - 2; i += 3) {
 680                     if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
 681                         output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
 682                     else
 683                         output_data(" %d", pointer[i+SLC_FUNC]);
 684                     switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
 685                     case SLC_NOSUPPORT:
 686                         output_data(" NOSUPPORT"); break;
 687                     case SLC_CANTCHANGE:
 688                         output_data(" CANTCHANGE"); break;
 689                     case SLC_VARIABLE:
 690                         output_data(" VARIABLE"); break;
 691                     case SLC_DEFAULT:
 692                         output_data(" DEFAULT"); break;
 693                     }
 694                     output_data("%s%s%s",
 695                         pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
 696                         pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
 697                         pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
 698                     if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
 699                                                 SLC_FLUSHOUT| SLC_LEVELBITS)) {
 700                         output_data("(0x%x)", pointer[i+SLC_FLAGS]);
 701                     }
 702                     output_data(" %d;", pointer[i+SLC_VALUE]);
 703                     if ((pointer[i+SLC_VALUE] == IAC) &&
 704                         (pointer[i+SLC_VALUE+1] == IAC))
 705                                 i++;
 706                 }
 707                 for (; i < length; i++) {
 708                     output_data(" ?%d?", pointer[i]);
 709                 }
 710                 break;
 711
 712             case LM_MODE:
 713                 output_data("MODE ");
 714                 if (length < 3) {
 715                     output_data("(no mode??\?)");
 716                     break;
 717                 }
 718                 {
 719                     char tbuf[32];
 720                     sprintf(tbuf, "%s%s%s%s%s",
 721                         pointer[2]&MODE_EDIT ? "|EDIT" : "",
 722                         pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
 723                         pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
 724                         pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
 725                         pointer[2]&MODE_ACK ? "|ACK" : "");
 726                     output_data("%s", tbuf[1] ? &tbuf[1] : "0");
 727                 }
 728                 if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
 729                     output_data(" (0x%x)", pointer[2]);
 730                 }
 731                 for (i = 3; i < length; i++) {
 732                     output_data(" ?0x%x?", pointer[i]);
 733                 }
 734                 break;
 735             default:
 736                 output_data("%d (unknown)", pointer[1]);
 737                 for (i = 2; i < length; i++) {
 738                     output_data(" %d", pointer[i]);
 739                 }
 740             }
 741             break;
 742
 743         case TELOPT_STATUS: {
 744             const char *cp;
 745             int j, k;
 746
 747             output_data("STATUS");
 748
 749             switch (pointer[1]) {
 750             default:
 751                 if (pointer[1] == TELQUAL_SEND)
 752                     output_data(" SEND");
 753                 else
 754                     output_data(" %d (unknown)", pointer[1]);
 755                 for (i = 2; i < length; i++) {
 756                     output_data(" ?%d?", pointer[i]);
 757                 }
 758                 break;
 759             case TELQUAL_IS:
 760                 output_data(" IS\r\n");
 761
 762                 for (i = 2; i < length; i++) {
 763                     switch(pointer[i]) {
 764                     case DO:    cp = "DO"; goto common2;
 765                     case DONT:  cp = "DONT"; goto common2;
 766                     case WILL:  cp = "WILL"; goto common2;
 767                     case WONT:  cp = "WONT"; goto common2;
 768                     common2:
 769                         i++;
 770                         if (TELOPT_OK(pointer[i]))
 771                             output_data(" %s %s", cp, TELOPT(pointer[i]));
 772                         else
 773                             output_data(" %s %d", cp, pointer[i]);
 774
 775                         output_data("\r\n");
 776                         break;
 777
 778                     case SB:
 779                         output_data(" SB ");
 780                         i++;
 781                         j = k = i;
 782                         while (j < length) {
 783                             if (pointer[j] == SE) {
 784                                 if (j+1 == length)
 785                                     break;
 786                                 if (pointer[j+1] == SE)
 787                                     j++;
 788                                 else
 789                                     break;
 790                             }
 791                             pointer[k++] = pointer[j++];
 792                         }
 793                         printsub(0, &pointer[i], k - i);
 794                         if (i < length) {
 795                             output_data(" SE");
 796                             i = j;
 797                         } else
 798                             i = j - 1;
 799
 800                         output_data("\r\n");
 801
 802                         break;
 803
 804                     default:
 805                         output_data(" %d", pointer[i]);
 806                         break;
 807                     }
 808                 }
 809                 break;
 810             }
 811             break;
 812           }
 813
 814         case TELOPT_XDISPLOC:
 815             output_data("X-DISPLAY-LOCATION ");
 816             switch (pointer[1]) {
 817             case TELQUAL_IS:
 818                 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
 819                 break;
 820             case TELQUAL_SEND:
 821                 output_data("SEND");
 822                 break;
 823             default:
 824                 output_data("- unknown qualifier %d (0x%x).",
 825                                 pointer[1], pointer[1]);
 826             }
 827             break;
 828
 829         case TELOPT_NEW_ENVIRON:
 830             output_data("NEW-ENVIRON ");
 831             goto env_common1;
 832         case TELOPT_OLD_ENVIRON:
 833             output_data("OLD-ENVIRON");
 834         env_common1:
 835             switch (pointer[1]) {
 836             case TELQUAL_IS:
 837                 output_data("IS ");
 838                 goto env_common;
 839             case TELQUAL_SEND:
 840                 output_data("SEND ");
 841                 goto env_common;
 842             case TELQUAL_INFO:
 843                 output_data("INFO ");
 844             env_common:
 845                 {
 846                     int noquote = 2;
 847                     for (i = 2; i < length; i++ ) {
 848                         switch (pointer[i]) {
 849                         case NEW_ENV_VAR:
 850                             output_data("\" VAR " + noquote);
 851                             noquote = 2;
 852                             break;
 853
 854                         case NEW_ENV_VALUE:
 855                             output_data("\" VALUE " + noquote);
 856                             noquote = 2;
 857                             break;
 858
 859                         case ENV_ESC:
 860                             output_data("\" ESC " + noquote);
 861                             noquote = 2;
 862                             break;
 863
 864                         case ENV_USERVAR:
 865                             output_data("\" USERVAR " + noquote);
 866                             noquote = 2;
 867                             break;
 868
 869                         default:
 870                             if (isprint(pointer[i]) && pointer[i] != '"') {
 871                                 if (noquote) {
 872                                     output_data("\"");
 873                                     noquote = 0;
 874                                 }
 875                                 output_data("%c", pointer[i]);
 876                             } else {
 877                                 output_data("\" %03o " + noquote,
 878                                                         pointer[i]);
 879                                 noquote = 2;
 880                             }
 881                             break;
 882                         }
 883                     }
 884                     if (!noquote)
 885                         output_data("\"");
 886                     break;
 887                 }
 888             }
 889             break;
 890
 891 #ifdef  AUTHENTICATION
 892         case TELOPT_AUTHENTICATION:
 893             output_data("AUTHENTICATION");
 894
 895             if (length < 2) {
 896                 output_data(" (empty suboption??\?)");
 897                 break;
 898             }
 899             switch (pointer[1]) {
 900             case TELQUAL_REPLY:
 901             case TELQUAL_IS:
 902                 output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
 903                                                         "IS" : "REPLY");
 904                 if (AUTHTYPE_NAME_OK(pointer[2]))
 905                     output_data("%s ", AUTHTYPE_NAME(pointer[2]));
 906                 else
 907                     output_data("%d ", pointer[2]);
 908                 if (length < 3) {
 909                     output_data("(partial suboption??\?)");
 910                     break;
 911                 }
 912                 output_data("%s|%s",
 913                         ((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
 914                         "CLIENT" : "SERVER",
 915                         ((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
 916                         "MUTUAL" : "ONE-WAY");
 917
 918                 {
 919                     char buf[512];
 920                     auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
 921                     output_data("%s", buf);
 922                 }
 923                 break;
 924
 925             case TELQUAL_SEND:
 926                 i = 2;
 927                 output_data(" SEND ");
 928                 while (i < length) {
 929                     if (AUTHTYPE_NAME_OK(pointer[i]))
 930                         output_data("%s ", AUTHTYPE_NAME(pointer[i]));
 931                     else
 932                         output_data("%d ", pointer[i]);
 933                     if (++i >= length) {
 934                         output_data("(partial suboption??\?)");
 935                         break;
 936                     }
 937                     output_data("%s|%s ",
 938                         ((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
 939                                                         "CLIENT" : "SERVER",
 940                         ((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
 941                                                         "MUTUAL" : "ONE-WAY");
 942                     ++i;
 943                 }
 944                 break;
 945
 946             case TELQUAL_NAME:
 947                 output_data(" NAME \"%.*s\"", length - 2, pointer + 2);
 948                 break;
 949
 950             default:
 951                     for (i = 2; i < length; i++) {
 952                         output_data(" ?%d?", pointer[i]);
 953                     }
 954                     break;
 955             }
 956             break;
 957 #endif
 958
 959 #ifdef  ENCRYPTION
 960         case TELOPT_ENCRYPT:
 961             output_data("ENCRYPT");
 962             if (length < 2) {
 963                 output_data(" (empty suboption??\?)");
 964                 break;
 965             }
 966             switch (pointer[1]) {
 967             case ENCRYPT_START:
 968                 output_data(" START");
 969                 break;
 970
 971             case ENCRYPT_END:
 972                 output_data(" END");
 973                 break;
 974
 975             case ENCRYPT_REQSTART:
 976                 output_data(" REQUEST-START");
 977                 break;
 978
 979             case ENCRYPT_REQEND:
 980                 output_data(" REQUEST-END");
 981                 break;
 982
 983             case ENCRYPT_IS:
 984             case ENCRYPT_REPLY:
 985                 output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
 986                                                         "IS" : "REPLY");
 987                 if (length < 3) {
 988                     output_data(" (partial suboption??\?)");
 989                     break;
 990                 }
 991                 if (ENCTYPE_NAME_OK(pointer[2]))
 992                     output_data("%s ", ENCTYPE_NAME(pointer[2]));
 993                 else
 994                     output_data(" %d (unknown)", pointer[2]);
 995
 996                 {
 997                     char buf[512];
 998                     encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
 999                     output_data("%s", buf);
1000                 }
1001                 break;
1002
1003             case ENCRYPT_SUPPORT:
1004                 i = 2;
1005                 output_data(" SUPPORT ");
1006                 while (i < length) {
1007                     if (ENCTYPE_NAME_OK(pointer[i]))
1008                         output_data("%s ", ENCTYPE_NAME(pointer[i]));
1009                     else
1010                         output_data("%d ", pointer[i]);
1011                     i++;
1012                 }
1013                 break;
1014
1015             case ENCRYPT_ENC_KEYID:
1016                 output_data(" ENC_KEYID");
1017                 goto encommon;
1018
1019             case ENCRYPT_DEC_KEYID:
1020                 output_data(" DEC_KEYID");
1021                 goto encommon;
1022
1023             default:
1024                 output_data(" %d (unknown)", pointer[1]);
1025             encommon:
1026                 for (i = 2; i < length; i++) {
1027                     output_data(" %d", pointer[i]);
1028                 }
1029                 break;
1030             }
1031             break;
1032 #endif  /* ENCRYPTION */
1033
1034         default:
1035             if (TELOPT_OK(pointer[0]))
1036                 output_data("%s (unknown)", TELOPT(pointer[0]));
1037             else
1038                 output_data("%d (unknown)", pointer[i]);
1039             for (i = 1; i < length; i++) {
1040                 output_data(" %d", pointer[i]);
1041             }
1042             break;
1043         }
1044         output_data("\r\n");
1045 }
1046
1047 /*
1048  * Dump a data buffer in hex and ascii to the output data stream.
1049  */
1050 void
1051 printdata(const char *tag, char *ptr, int cnt)
1052 {
1053         int i;
1054         char xbuf[30];
1055
1056         while (cnt) {
1057                 /* flush net output buffer if no room for new data) */
1058                 if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1059                         netflush();
1060                 }
1061
1062                 /* add a line of output */
1063                 output_data("%s: ", tag);
1064                 for (i = 0; i < 20 && cnt; i++) {
1065                         output_data("%02x", *ptr);
1066                         if (isprint(*ptr)) {
1067                                 xbuf[i] = *ptr;
1068                         } else {
1069                                 xbuf[i] = '.';
1070                         }
1071                         if (i % 2) {
1072                                 output_data(" ");
1073                         }
1074                         cnt--;
1075                         ptr++;
1076                 }
1077                 xbuf[i] = '\0';
1078                 output_data(" %s\r\n", xbuf );
1079         }
1080 }
1081 #endif /* DIAGNOSTICS */