libexec/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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)utility.c        8.4 (Berkeley) 5/30/95
  30  * $FreeBSD: src/crypto/telnet/telnetd/utility.c,v 1.5.2.4 2002/04/13 10:59:09 markm Exp $
  31  */
  32
  33 #if defined(__FreeBSD__) || defined(__DragonFly__)
  34 #include <locale.h>
  35 #include <sys/utsname.h>
  36 #endif
  37 #include <string.h>
  38 #define PRINTOPTIONS
  39 #include "telnetd.h"
  40
  41 #ifdef  AUTHENTICATION
  42 #include <libtelnet/auth.h>
  43 #endif
  44 #ifdef  ENCRYPTION
  45 #include <libtelnet/encrypt.h>
  46 #endif
  47
  48 /*
  49  * utility functions performing io related tasks
  50  */
  51
  52 /*
  53  * ttloop
  54  *
  55  *      A small subroutine to flush the network output buffer, get some data
  56  * from the network, and pass it through the telnet state machine.  We
  57  * also flush the pty input buffer (by dropping its data) if it becomes
  58  * too full.
  59  */
  60
  61 void
  62 ttloop(void)
  63 {
  64
  65     DIAG(TD_REPORT, output_data("td: ttloop\r\n"));
  66     if (nfrontp - nbackp > 0) {
  67         netflush();
  68     }
  69     ncc = read(net, netibuf, sizeof netibuf);
  70     if (ncc < 0) {
  71         syslog(LOG_INFO, "ttloop:  read: %m");
  72         exit(1);
  73     } else if (ncc == 0) {
  74         syslog(LOG_INFO, "ttloop:  peer died: %m");
  75         exit(1);
  76     }
  77     DIAG(TD_REPORT, output_data("td: ttloop read %d chars\r\n", ncc));
  78     netip = netibuf;
  79     telrcv();                   /* state machine */
  80     if (ncc > 0) {
  81         pfrontp = pbackp = ptyobuf;
  82         telrcv();
  83     }
  84 }  /* end of ttloop */
  85
  86 /*
  87  * Check a descriptor to see if out of band data exists on it.
  88  */
  89 int
  90 stilloob(int s)
  91 {
  92     static struct timeval timeout = { 0, 0 };
  93     fd_set      excepts;
  94     int value;
  95
  96     do {
  97         FD_ZERO(&excepts);
  98         FD_SET(s, &excepts);
  99         memset((char *)&timeout, 0, sizeof timeout);
 100         value = select(s+1, NULL, NULL, &excepts, &timeout);
 101     } while ((value == -1) && (errno == EINTR));
 102
 103     if (value < 0) {
 104         fatalperror(pty, "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                 DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
 122                 n = write(pty, pbackp, n);
 123         }
 124         if (n < 0) {
 125                 if (errno == EWOULDBLOCK || errno == EINTR)
 126                         return;
 127                 cleanup(0);
 128         }
 129         pbackp += n;
 130         if (pbackp == pfrontp)
 131                 pbackp = pfrontp = ptyobuf;
 132 }
 133
 134 /*
 135  * nextitem()
 136  *
 137  *      Return the address of the next "item" in the TELNET data
 138  * stream.  This will be the address of the next character if
 139  * the current address is a user data character, or it will
 140  * be the address of the character following the TELNET command
 141  * if the current address is a TELNET IAC ("I Am a Command")
 142  * character.
 143  */
 144 static char *
 145 nextitem(char *current)
 146 {
 147     if ((*current&0xff) != IAC) {
 148         return current+1;
 149     }
 150     switch (*(current+1)&0xff) {
 151     case DO:
 152     case DONT:
 153     case WILL:
 154     case WONT:
 155         return current+3;
 156     case SB:            /* loop forever looking for the SE */
 157         {
 158             char *look = current+2;
 159
 160             for (;;) {
 161                 if ((*look++&0xff) == IAC) {
 162                     if ((*look++&0xff) == SE) {
 163                         return look;
 164                     }
 165                 }
 166             }
 167         }
 168     default:
 169         return current+2;
 170     }
 171 }  /* end of nextitem */
 172
 173 /*
 174  * netclear()
 175  *
 176  *      We are about to do a TELNET SYNCH operation.  Clear
 177  * the path to the network.
 178  *
 179  *      Things are a bit tricky since we may have sent the first
 180  * byte or so of a previous TELNET command into the network.
 181  * So, we have to scan the network buffer from the beginning
 182  * until we are up to where we want to be.
 183  *
 184  *      A side effect of what we do, just to keep things
 185  * simple, is to clear the urgent data pointer.  The principal
 186  * caller should be setting the urgent data pointer AFTER calling
 187  * us in any case.
 188  */
 189 void
 190 netclear(void)
 191 {
 192     char *thisitem, *next;
 193     char *good;
 194 #define wewant(p)       ((nfrontp > p) && ((*p&0xff) == IAC) && \
 195                                 ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
 196
 197 #ifdef  ENCRYPTION
 198     thisitem = nclearto > netobuf ? nclearto : netobuf;
 199 #else   /* ENCRYPTION */
 200     thisitem = netobuf;
 201 #endif  /* ENCRYPTION */
 202
 203     while ((next = nextitem(thisitem)) <= nbackp) {
 204         thisitem = next;
 205     }
 206
 207     /* Now, thisitem is first before/at boundary. */
 208
 209 #ifdef  ENCRYPTION
 210     good = nclearto > netobuf ? nclearto : netobuf;
 211 #else   /* ENCRYPTION */
 212     good = netobuf;     /* where the good bytes go */
 213 #endif  /* ENCRYPTION */
 214
 215     while (nfrontp > thisitem) {
 216         if (wewant(thisitem)) {
 217             int length;
 218
 219             next = thisitem;
 220             do {
 221                 next = nextitem(next);
 222             } while (wewant(next) && (nfrontp > next));
 223             length = next-thisitem;
 224             memmove(good, thisitem, length);
 225             good += length;
 226             thisitem = next;
 227         } else {
 228             thisitem = nextitem(thisitem);
 229         }
 230     }
 231
 232     nbackp = netobuf;
 233     nfrontp = good;             /* next byte to be sent */
 234     neturg = 0;
 235 }  /* end of netclear */
 236
 237 /*
 238  *  netflush
 239  *              Send as much data as possible to the network,
 240  *      handling requests for urgent data.
 241  */
 242 void
 243 netflush(void)
 244 {
 245     int n;
 246     extern int not42;
 247
 248     while ((n = nfrontp - nbackp) > 0) {
 249 #if 0
 250         /* XXX This causes output_data() to recurse and die */
 251         DIAG(TD_REPORT, {
 252             n += output_data("td: netflush %d chars\r\n", n);
 253         });
 254 #endif
 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  /* ENCRYPTION */
 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 ((neturg == 0) || (not42 == 0)) {
 270             n = write(net, nbackp, n);  /* normal write */
 271         } else {
 272             n = neturg - nbackp;
 273             /*
 274              * In 4.2 (and 4.3) systems, there is some question about
 275              * what byte in a sendOOB operation is the "OOB" data.
 276              * To make ourselves compatible, we only send ONE byte
 277              * out of band, the one WE THINK should be OOB (though
 278              * we really have more the TCP philosophy of urgent data
 279              * rather than the Unix philosophy of OOB data).
 280              */
 281             if (n > 1) {
 282                 n = send(net, nbackp, n-1, 0);  /* send URGENT all by itself */
 283             } else {
 284                 n = send(net, nbackp, n, MSG_OOB);      /* URGENT data */
 285             }
 286         }
 287         if (n == -1) {
 288             if (errno == EWOULDBLOCK || errno == EINTR)
 289                 continue;
 290             cleanup(0);
 291             /* NOTREACHED */
 292         }
 293         nbackp += n;
 294 #ifdef  ENCRYPTION
 295         if (nbackp > nclearto)
 296             nclearto = 0;
 297 #endif  /* ENCRYPTION */
 298         if (nbackp >= neturg) {
 299             neturg = 0;
 300         }
 301         if (nbackp == nfrontp) {
 302             nbackp = nfrontp = netobuf;
 303 #ifdef  ENCRYPTION
 304             nclearto = 0;
 305 #endif  /* ENCRYPTION */
 306         }
 307     }
 308     return;
 309 }  /* end of netflush */
 310
 311
 312 /*
 313  * miscellaneous functions doing a variety of little jobs follow ...
 314  */
 315
 316
 317 void
 318 fatal(int f, const char *msg)
 319 {
 320         char buf[BUFSIZ];
 321
 322         (void) snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
 323 #ifdef  ENCRYPTION
 324         if (encrypt_output) {
 325                 /*
 326                  * Better turn off encryption first....
 327                  * Hope it flushes...
 328                  */
 329                 encrypt_send_end();
 330                 netflush();
 331         }
 332 #endif  /* ENCRYPTION */
 333         (void) write(f, buf, (int)strlen(buf));
 334         sleep(1);       /*XXX*/
 335         exit(1);
 336 }
 337
 338 void
 339 fatalperror(int f, const char *msg)
 340 {
 341         char buf[BUFSIZ];
 342
 343         (void) snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(errno));
 344         fatal(f, buf);
 345 }
 346
 347 char editedhost[32];
 348
 349 void
 350 edithost(char *pat, char *host)
 351 {
 352         char *res = editedhost;
 353
 354         if (!pat)
 355                 pat = strdup("");
 356         while (*pat) {
 357                 switch (*pat) {
 358
 359                 case '#':
 360                         if (*host)
 361                                 host++;
 362                         break;
 363
 364                 case '@':
 365                         if (*host)
 366                                 *res++ = *host++;
 367                         break;
 368
 369                 default:
 370                         *res++ = *pat;
 371                         break;
 372                 }
 373                 if (res == &editedhost[sizeof editedhost - 1]) {
 374                         *res = '\0';
 375                         return;
 376                 }
 377                 pat++;
 378         }
 379         if (*host)
 380                 (void) strncpy(res, host,
 381                                 sizeof editedhost - (res - editedhost) -1);
 382         else
 383                 *res = '\0';
 384         editedhost[sizeof editedhost - 1] = '\0';
 385 }
 386
 387 static char *putlocation;
 388
 389 static void
 390 putstr(const char *s)
 391 {
 392
 393         while (*s)
 394                 putchr(*s++);
 395 }
 396
 397 void
 398 putchr(int cc)
 399 {
 400         *putlocation++ = cc;
 401 }
 402
 403 #if defined(__FreeBSD__) || defined(__DragonFly__)
 404 static char fmtstr[] = { "%+" };
 405 #else
 406 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
 407 #endif
 408
 409 void
 410 putf(char *cp, char *where)
 411 {
 412         char *slash;
 413         time_t t;
 414         char db[100];
 415 #if defined(__FreeBSD__) || defined(__DragonFly__)
 416         static struct utsname kerninfo;
 417
 418         if (!*kerninfo.sysname)
 419                 uname(&kerninfo);
 420 #endif
 421
 422         putlocation = where;
 423
 424         while (*cp) {
 425                 if (*cp =='\n') {
 426                         putstr("\r\n");
 427                         cp++;
 428                         continue;
 429                 } else if (*cp != '%') {
 430                         putchr(*cp++);
 431                         continue;
 432                 }
 433                 switch (*++cp) {
 434
 435                 case 't':
 436 #ifdef  STREAMSPTY
 437                         /* names are like /dev/pts/2 -- we want pts/2 */
 438                         slash = strchr(line+1, '/');
 439 #else
 440                         slash = strrchr(line, '/');
 441 #endif
 442                         if (slash == (char *) 0)
 443                                 putstr(line);
 444                         else
 445                                 putstr(&slash[1]);
 446                         break;
 447
 448                 case 'h':
 449                         putstr(editedhost);
 450                         break;
 451
 452                 case 'd':
 453 #if defined(__FreeBSD__) || defined(__DragonFly__)
 454                         setlocale(LC_TIME, "");
 455 #endif
 456                         (void)time(&t);
 457                         (void)strftime(db, sizeof(db), fmtstr, localtime(&t));
 458                         putstr(db);
 459                         break;
 460
 461 #if defined(__FreeBSD__) || defined(__DragonFly__)
 462                 case 's':
 463                         putstr(kerninfo.sysname);
 464                         break;
 465
 466                 case 'm':
 467                         putstr(kerninfo.machine);
 468                         break;
 469
 470                 case 'r':
 471                         putstr(kerninfo.release);
 472                         break;
 473
 474                 case 'v':
 475                         putstr(kerninfo.version);
 476                         break;
 477 #endif
 478
 479                 case '%':
 480                         putchr('%');
 481                         break;
 482                 }
 483                 cp++;
 484         }
 485 }
 486
 487 #ifdef DIAGNOSTICS
 488 /*
 489  * Print telnet options and commands in plain text, if possible.
 490  */
 491 void
 492 printoption(const char *fmt, int option)
 493 {
 494         if (TELOPT_OK(option))
 495                 output_data("%s %s\r\n", fmt, TELOPT(option));
 496         else if (TELCMD_OK(option))
 497                 output_data("%s %s\r\n", fmt, TELCMD(option));
 498         else
 499                 output_data("%s %d\r\n", fmt, option);
 500         return;
 501 }
 502
 503 void
 504 printsub(char direction, unsigned char *pointer, int length)
 505 {
 506     int i = 0;
 507
 508         if (!(diagnostic & TD_OPTIONS))
 509                 return;
 510
 511         if (direction) {
 512             output_data("td: %s suboption ",
 513                                         direction == '<' ? "recv" : "send");
 514             if (length >= 3) {
 515                 int j;
 516
 517                 i = pointer[length-2];
 518                 j = pointer[length-1];
 519
 520                 if (i != IAC || j != SE) {
 521                     output_data("(terminated by ");
 522                     if (TELOPT_OK(i))
 523                         output_data("%s ", TELOPT(i));
 524                     else if (TELCMD_OK(i))
 525                         output_data("%s ", TELCMD(i));
 526                     else
 527                         output_data("%d ", i);
 528                     if (TELOPT_OK(j))
 529                         output_data("%s", TELOPT(j));
 530                     else if (TELCMD_OK(j))
 531                         output_data("%s", TELCMD(j));
 532                     else
 533                         output_data("%d", j);
 534                     output_data(", not IAC SE!) ");
 535                 }
 536             }
 537             length -= 2;
 538         }
 539         if (length < 1) {
 540             output_data("(Empty suboption??\?)");
 541             return;
 542         }
 543         switch (pointer[0]) {
 544         case TELOPT_TTYPE:
 545             output_data("TERMINAL-TYPE ");
 546             switch (pointer[1]) {
 547             case TELQUAL_IS:
 548                 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
 549                 break;
 550             case TELQUAL_SEND:
 551                 output_data("SEND");
 552                 break;
 553             default:
 554                 output_data(
 555                                 "- unknown qualifier %d (0x%x).",
 556                                 pointer[1], pointer[1]);
 557             }
 558             break;
 559         case TELOPT_TSPEED:
 560             output_data("TERMINAL-SPEED");
 561             if (length < 2) {
 562                 output_data(" (empty suboption??\?)");
 563                 break;
 564             }
 565             switch (pointer[1]) {
 566             case TELQUAL_IS:
 567                 output_data(" IS %.*s", length-2, (char *)pointer+2);
 568                 break;
 569             default:
 570                 if (pointer[1] == 1)
 571                     output_data(" SEND");
 572                 else
 573                     output_data(" %d (unknown)", pointer[1]);
 574                 for (i = 2; i < length; i++) {
 575                     output_data(" ?%d?", pointer[i]);
 576                 }
 577                 break;
 578             }
 579             break;
 580
 581         case TELOPT_LFLOW:
 582             output_data("TOGGLE-FLOW-CONTROL");
 583             if (length < 2) {
 584                 output_data(" (empty suboption??\?)");
 585                 break;
 586             }
 587             switch (pointer[1]) {
 588             case LFLOW_OFF:
 589                 output_data(" OFF"); break;
 590             case LFLOW_ON:
 591                 output_data(" ON"); break;
 592             case LFLOW_RESTART_ANY:
 593                 output_data(" RESTART-ANY"); break;
 594             case LFLOW_RESTART_XON:
 595                 output_data(" RESTART-XON"); break;
 596             default:
 597                 output_data(" %d (unknown)", pointer[1]);
 598             }
 599             for (i = 2; i < length; i++) {
 600                 output_data(" ?%d?", pointer[i]);
 601             }
 602             break;
 603
 604         case TELOPT_NAWS:
 605             output_data("NAWS");
 606             if (length < 2) {
 607                 output_data(" (empty suboption??\?)");
 608                 break;
 609             }
 610             if (length == 2) {
 611                 output_data(" ?%d?", pointer[1]);
 612                 break;
 613             }
 614             output_data(" %d %d (%d)",
 615                 pointer[1], pointer[2],
 616                 (int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
 617             if (length == 4) {
 618                 output_data(" ?%d?", pointer[3]);
 619                 break;
 620             }
 621             output_data(" %d %d (%d)",
 622                 pointer[3], pointer[4],
 623                 (int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
 624             for (i = 5; i < length; i++) {
 625                 output_data(" ?%d?", pointer[i]);
 626             }
 627             break;
 628
 629         case TELOPT_LINEMODE:
 630             output_data("LINEMODE ");
 631             if (length < 2) {
 632                 output_data(" (empty suboption??\?)");
 633                 break;
 634             }
 635             switch (pointer[1]) {
 636             case WILL:
 637                 output_data("WILL ");
 638                 goto common;
 639             case WONT:
 640                 output_data("WONT ");
 641                 goto common;
 642             case DO:
 643                 output_data("DO ");
 644                 goto common;
 645             case DONT:
 646                 output_data("DONT ");
 647             common:
 648                 if (length < 3) {
 649                     output_data("(no option??\?)");
 650                     break;
 651                 }
 652                 switch (pointer[2]) {
 653                 case LM_FORWARDMASK:
 654                     output_data("Forward Mask");
 655                     for (i = 3; i < length; i++) {
 656                         output_data(" %x", pointer[i]);
 657                     }
 658                     break;
 659                 default:
 660                     output_data("%d (unknown)", pointer[2]);
 661                     for (i = 3; i < length; i++) {
 662                         output_data(" %d", pointer[i]);
 663                     }
 664                     break;
 665                 }
 666                 break;
 667
 668             case LM_SLC:
 669                 output_data("SLC");
 670                 for (i = 2; i < length - 2; i += 3) {
 671                     if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
 672                         output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
 673                     else
 674                         output_data(" %d", pointer[i+SLC_FUNC]);
 675                     switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
 676                     case SLC_NOSUPPORT:
 677                         output_data(" NOSUPPORT"); break;
 678                     case SLC_CANTCHANGE:
 679                         output_data(" CANTCHANGE"); break;
 680                     case SLC_VARIABLE:
 681                         output_data(" VARIABLE"); break;
 682                     case SLC_DEFAULT:
 683                         output_data(" DEFAULT"); break;
 684                     }
 685                     output_data("%s%s%s",
 686                         pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
 687                         pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
 688                         pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
 689                     if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
 690                                                 SLC_FLUSHOUT| SLC_LEVELBITS)) {
 691                         output_data("(0x%x)", pointer[i+SLC_FLAGS]);
 692                     }
 693                     output_data(" %d;", pointer[i+SLC_VALUE]);
 694                     if ((pointer[i+SLC_VALUE] == IAC) &&
 695                         (pointer[i+SLC_VALUE+1] == IAC))
 696                                 i++;
 697                 }
 698                 for (; i < length; i++) {
 699                     output_data(" ?%d?", pointer[i]);
 700                 }
 701                 break;
 702
 703             case LM_MODE:
 704                 output_data("MODE ");
 705                 if (length < 3) {
 706                     output_data("(no mode??\?)");
 707                     break;
 708                 }
 709                 {
 710                     char tbuf[32];
 711                     sprintf(tbuf, "%s%s%s%s%s",
 712                         pointer[2]&MODE_EDIT ? "|EDIT" : "",
 713                         pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
 714                         pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
 715                         pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
 716                         pointer[2]&MODE_ACK ? "|ACK" : "");
 717                     output_data("%s", tbuf[1] ? &tbuf[1] : "0");
 718                 }
 719                 if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
 720                     output_data(" (0x%x)", pointer[2]);
 721                 }
 722                 for (i = 3; i < length; i++) {
 723                     output_data(" ?0x%x?", pointer[i]);
 724                 }
 725                 break;
 726             default:
 727                 output_data("%d (unknown)", pointer[1]);
 728                 for (i = 2; i < length; i++) {
 729                     output_data(" %d", pointer[i]);
 730                 }
 731             }
 732             break;
 733
 734         case TELOPT_STATUS: {
 735             const char *cp;
 736             int j, k;
 737
 738             output_data("STATUS");
 739
 740             switch (pointer[1]) {
 741             default:
 742                 if (pointer[1] == TELQUAL_SEND)
 743                     output_data(" SEND");
 744                 else
 745                     output_data(" %d (unknown)", pointer[1]);
 746                 for (i = 2; i < length; i++) {
 747                     output_data(" ?%d?", pointer[i]);
 748                 }
 749                 break;
 750             case TELQUAL_IS:
 751                 output_data(" IS\r\n");
 752
 753                 for (i = 2; i < length; i++) {
 754                     switch(pointer[i]) {
 755                     case DO:    cp = "DO"; goto common2;
 756                     case DONT:  cp = "DONT"; goto common2;
 757                     case WILL:  cp = "WILL"; goto common2;
 758                     case WONT:  cp = "WONT"; goto common2;
 759                     common2:
 760                         i++;
 761                         if (TELOPT_OK(pointer[i]))
 762                             output_data(" %s %s", cp, TELOPT(pointer[i]));
 763                         else
 764                             output_data(" %s %d", cp, pointer[i]);
 765
 766                         output_data("\r\n");
 767                         break;
 768
 769                     case SB:
 770                         output_data(" SB ");
 771                         i++;
 772                         j = k = i;
 773                         while (j < length) {
 774                             if (pointer[j] == SE) {
 775                                 if (j+1 == length)
 776                                     break;
 777                                 if (pointer[j+1] == SE)
 778                                     j++;
 779                                 else
 780                                     break;
 781                             }
 782                             pointer[k++] = pointer[j++];
 783                         }
 784                         printsub(0, &pointer[i], k - i);
 785                         if (i < length) {
 786                             output_data(" SE");
 787                             i = j;
 788                         } else
 789                             i = j - 1;
 790
 791                         output_data("\r\n");
 792
 793                         break;
 794
 795                     default:
 796                         output_data(" %d", pointer[i]);
 797                         break;
 798                     }
 799                 }
 800                 break;
 801             }
 802             break;
 803           }
 804
 805         case TELOPT_XDISPLOC:
 806             output_data("X-DISPLAY-LOCATION ");
 807             switch (pointer[1]) {
 808             case TELQUAL_IS:
 809                 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
 810                 break;
 811             case TELQUAL_SEND:
 812                 output_data("SEND");
 813                 break;
 814             default:
 815                 output_data("- unknown qualifier %d (0x%x).",
 816                                 pointer[1], pointer[1]);
 817             }
 818             break;
 819
 820         case TELOPT_NEW_ENVIRON:
 821             output_data("NEW-ENVIRON ");
 822             goto env_common1;
 823         case TELOPT_OLD_ENVIRON:
 824             output_data("OLD-ENVIRON");
 825         env_common1:
 826             switch (pointer[1]) {
 827             case TELQUAL_IS:
 828                 output_data("IS ");
 829                 goto env_common;
 830             case TELQUAL_SEND:
 831                 output_data("SEND ");
 832                 goto env_common;
 833             case TELQUAL_INFO:
 834                 output_data("INFO ");
 835             env_common:
 836                 {
 837                     int noquote = 2;
 838                     for (i = 2; i < length; i++ ) {
 839                         switch (pointer[i]) {
 840                         case NEW_ENV_VAR:
 841                             output_data("%s", "\" VAR " + noquote);
 842                             noquote = 2;
 843                             break;
 844
 845                         case NEW_ENV_VALUE:
 846                             output_data("%s", "\" VALUE " + noquote);
 847                             noquote = 2;
 848                             break;
 849
 850                         case ENV_ESC:
 851                             output_data("%s", "\" ESC " + noquote);
 852                             noquote = 2;
 853                             break;
 854
 855                         case ENV_USERVAR:
 856                             output_data("%s", "\" USERVAR " + noquote);
 857                             noquote = 2;
 858                             break;
 859
 860                         default:
 861                             if (isprint(pointer[i]) && pointer[i] != '"') {
 862                                 if (noquote) {
 863                                     output_data("\"");
 864                                     noquote = 0;
 865                                 }
 866                                 output_data("%c", pointer[i]);
 867                             } else {
 868                                 output_data("\" %03o " + noquote,
 869                                                         pointer[i]);
 870                                 noquote = 2;
 871                             }
 872                             break;
 873                         }
 874                     }
 875                     if (!noquote)
 876                         output_data("\"");
 877                     break;
 878                 }
 879             }
 880             break;
 881
 882 #ifdef  AUTHENTICATION
 883         case TELOPT_AUTHENTICATION:
 884             output_data("AUTHENTICATION");
 885
 886             if (length < 2) {
 887                 output_data(" (empty suboption??\?)");
 888                 break;
 889             }
 890             switch (pointer[1]) {
 891             case TELQUAL_REPLY:
 892             case TELQUAL_IS:
 893                 output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
 894                                                         "IS" : "REPLY");
 895                 if (AUTHTYPE_NAME_OK(pointer[2]))
 896                     output_data("%s ", AUTHTYPE_NAME(pointer[2]));
 897                 else
 898                     output_data("%d ", pointer[2]);
 899                 if (length < 3) {
 900                     output_data("(partial suboption??\?)");
 901                     break;
 902                 }
 903                 output_data("%s|%s",
 904                         ((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
 905                         "CLIENT" : "SERVER",
 906                         ((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
 907                         "MUTUAL" : "ONE-WAY");
 908
 909                 {
 910                     char buf[512];
 911                     auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
 912                     output_data("%s", buf);
 913                 }
 914                 break;
 915
 916             case TELQUAL_SEND:
 917                 i = 2;
 918                 output_data(" SEND ");
 919                 while (i < length) {
 920                     if (AUTHTYPE_NAME_OK(pointer[i]))
 921                         output_data("%s ", AUTHTYPE_NAME(pointer[i]));
 922                     else
 923                         output_data("%d ", pointer[i]);
 924                     if (++i >= length) {
 925                         output_data("(partial suboption??\?)");
 926                         break;
 927                     }
 928                     output_data("%s|%s ",
 929                         ((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
 930                                                         "CLIENT" : "SERVER",
 931                         ((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
 932                                                         "MUTUAL" : "ONE-WAY");
 933                     ++i;
 934                 }
 935                 break;
 936
 937             case TELQUAL_NAME:
 938                 output_data(" NAME \"%.*s\"", length - 2, pointer + 2);
 939                 break;
 940
 941             default:
 942                     for (i = 2; i < length; i++) {
 943                         output_data(" ?%d?", pointer[i]);
 944                     }
 945                     break;
 946             }
 947             break;
 948 #endif
 949
 950 #ifdef  ENCRYPTION
 951         case TELOPT_ENCRYPT:
 952             output_data("ENCRYPT");
 953             if (length < 2) {
 954                 output_data(" (empty suboption??\?)");
 955                 break;
 956             }
 957             switch (pointer[1]) {
 958             case ENCRYPT_START:
 959                 output_data(" START");
 960                 break;
 961
 962             case ENCRYPT_END:
 963                 output_data(" END");
 964                 break;
 965
 966             case ENCRYPT_REQSTART:
 967                 output_data(" REQUEST-START");
 968                 break;
 969
 970             case ENCRYPT_REQEND:
 971                 output_data(" REQUEST-END");
 972                 break;
 973
 974             case ENCRYPT_IS:
 975             case ENCRYPT_REPLY:
 976                 output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
 977                                                         "IS" : "REPLY");
 978                 if (length < 3) {
 979                     output_data(" (partial suboption??\?)");
 980                     break;
 981                 }
 982                 if (ENCTYPE_NAME_OK(pointer[2]))
 983                     output_data("%s ", ENCTYPE_NAME(pointer[2]));
 984                 else
 985                     output_data(" %d (unknown)", pointer[2]);
 986
 987                 {
 988                     char buf[512];
 989                     encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
 990                     output_data("%s", buf);
 991                 }
 992                 break;
 993
 994             case ENCRYPT_SUPPORT:
 995                 i = 2;
 996                 output_data(" SUPPORT ");
 997                 while (i < length) {
 998                     if (ENCTYPE_NAME_OK(pointer[i]))
 999                         output_data("%s ", ENCTYPE_NAME(pointer[i]));
1000                     else
1001                         output_data("%d ", pointer[i]);
1002                     i++;
1003                 }
1004                 break;
1005
1006             case ENCRYPT_ENC_KEYID:
1007                 output_data(" ENC_KEYID");
1008                 goto encommon;
1009
1010             case ENCRYPT_DEC_KEYID:
1011                 output_data(" DEC_KEYID");
1012                 goto encommon;
1013
1014             default:
1015                 output_data(" %d (unknown)", pointer[1]);
1016             encommon:
1017                 for (i = 2; i < length; i++) {
1018                     output_data(" %d", pointer[i]);
1019                 }
1020                 break;
1021             }
1022             break;
1023 #endif  /* ENCRYPTION */
1024
1025         default:
1026             if (TELOPT_OK(pointer[0]))
1027                 output_data("%s (unknown)", TELOPT(pointer[0]));
1028             else
1029                 output_data("%d (unknown)", pointer[i]);
1030             for (i = 1; i < length; i++) {
1031                 output_data(" %d", pointer[i]);
1032             }
1033             break;
1034         }
1035         output_data("\r\n");
1036 }
1037
1038 /*
1039  * Dump a data buffer in hex and ascii to the output data stream.
1040  */
1041 void
1042 printdata(const char *tag, char *ptr, int cnt)
1043 {
1044         int i;
1045         char xbuf[30];
1046
1047         while (cnt) {
1048                 /* flush net output buffer if no room for new data) */
1049                 if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1050                         netflush();
1051                 }
1052
1053                 /* add a line of output */
1054                 output_data("%s: ", tag);
1055                 for (i = 0; i < 20 && cnt; i++) {
1056                         output_data("%02x", *ptr);
1057                         if (isprint(*ptr)) {
1058                                 xbuf[i] = *ptr;
1059                         } else {
1060                                 xbuf[i] = '.';
1061                         }
1062                         if (i % 2) {
1063                                 output_data(" ");
1064                         }
1065                         cnt--;
1066                         ptr++;
1067                 }
1068                 xbuf[i] = '\0';
1069                 output_data(" %s\r\n", xbuf );
1070         }
1071 }
1072 #endif /* DIAGNOSTICS */