1
2This is a distribution of both client and server telnet. These programs
3have been compiled on:
4 telnet telnetd
5 4.4 BSD-Lite x x
6 4.3 BSD Reno X X
7 UNICOS 9.1 X X
8 UNICOS 9.0 X X
9 UNICOS 8.0 X X
10 BSDI 2.0 X X
11 Solaris 2.4 x x (no linemode in server)
12 SunOs 4.1.4 X X (no linemode in server)
13 Ultrix 4.3 X X (no linemode in server)
14 Ultrix 4.1 X X (no linemode in server)
15
16In addition, previous versions have been compiled on the following
17machines, but were not available for testing this version.
18 telnet telnetd
19 Next1.0 X X
20 UNICOS 8.3 X X
21 UNICOS 7.C X X
22 UNICOS 7.0 X X
23 SunOs 4.0.3c X X (no linemode in server)
24 4.3 BSD X X (no linemode in server)
25 DYNIX V3.0.12 X X (no linemode in server)
26 Ultrix 3.1 X X (no linemode in server)
27 Ultrix 4.0 X X (no linemode in server)
28 SunOs 3.5 X X (no linemode in server)
29 SunOs 4.1.3 X X (no linemode in server)
30 Solaris 2.2 x x (no linemode in server)
31 Solaris 2.3 x x (no linemode in server)
32 BSDI 1.0 X X
33 BSDI 1.1 X X
34 DYNIX V3.0.17.9 X X (no linemode in server)
35 HP-UX 8.0 x x (no linemode in server)
36
37This code should work, but there are no guarantees.
38
39Oct 23, 1995
40
41This is a bugfix release.
42
43 The change in the previous release from using makeutx() to
44 pututxline() caused problems on SunOS/Solaris. It has been
45 changed back to using makeutx(). Symptoms include users
46 getting error messages when logging in about not being able
47 to open the tty.
48
49 Using memmove() instead of memcpy() caused problems under
50 SunOS 4.x, since it doesn't have memmove(). Config.generic
51 has been modified to include mem.o for SunOS 4.x.
52
53 Some new code was added to telnetd to do some environment
54 variable cleanup before execing login. Thanks to Sam Hartman
55 at MIT for pointing this out.
56
57 A couple of other minor bugfixes.
58
59May 30, 1995
60
61This release represents what is on the 4.4BSD-Lite2 release, which
62should be the final BSD release. I will continue to support of
63telnet, The code (without encryption) is available via anonymous ftp
64from ftp.cray.com, in src/telnet/telnet.YY.MM.DD.NE.tar.Z, where
65YY.MM.DD is replaced with the year, month and day of the release.
66If you can't find it at one of these places, at some point in the
67near future information about the latest releases should be available
68from ftp.borman.com.
69
70In addition, the version with the encryption code is available via
71ftp from net-dist.mit.edu, in the directory /pub/telnet. There
72is a README file there that gives further information on how
73to get the distribution.
74
75Questions, comments, bug reports and bug fixes can be sent to
76one of these addresses:
77 dab@borman.com
78 dab@cray.com
79 dab@bsdi.com
80
81This release is mainly bug fixes and code cleanup.
82
83 Replace all calls to bcopy()/bzero() with calls to
84 memmove()/memset() and all calls to index()/rindex()
85 with calls to strchr()/strrchr().
86
87 Add some missing diagnostics for option tracing
88 to telnetd.
89
90 Add support for BSDI 2.0 and Solaris 2.4.
91
92 Add support for UNICOS 8.0
93
94 Get rid of expanded tabs and trailing white spaces.
95
96 From Paul Vixie:
97 Fix for telnet going into an endless spin
98 when the session dies abnormally.
99
100 From Jef Poskanzer:
101 Changes to allow telnet to compile
102 under SunOS 3.5.
103
104 From Philip Guenther:
105 makeutx() doesn't expand utmpx,
106 use pututxline() instead.
107
108 From Chris Torek:
109 Add a sleep(1) before execing login
110 to avoid race condition that can eat
111 up the login prompt.
112 Use terminal speed directly if it is
113 not an encoded value.
114
115 From Steve Parker:
116 Fix to realloc() call. Fix for execing
117 login on solaris with no user name.
118
119January 19, 1994
120
121This is a list of some of the changes since the last tar release
122of telnet/telnetd. There are probably other changes that aren't
123listed here, but this should hit a lot of the main ones.
124
125 General:
126 Changed #define for AUTHENTICATE to AUTHENTICATION
127 Changed #define for ENCRYPT to ENCRYPTION
128 Changed #define for DES_ENCRYPT to DES_ENCRYPTION
129
130 Added support for SPX authentication: -DSPX
131
132 Added support for Kerberos Version 5 authentication: -DKRB5
133
134 Added support for ANSI C function prototypes
135
136 Added support for the NEW-ENVIRON option (RFC-1572)
137 including support for USERVAR.
138
139 Made support for the old Environment Option (RFC-1408)
140 conditional on -DOLD_ENVIRON
141
142 Added #define ENV_HACK - support for RFC 1571
143
144 The encryption code is removed from the public distributions.
145 Domestic 4.4 BSD distributions contain the encryption code.
146
147 ENV_HACK: Code to deal with systems that only implement
148 the old ENVIRON option, and have reversed definitions
149 of ENV_VAR and ENV_VAL. Also fixes ENV processing in
150 client to handle things besides just the default set...
151
152 NO_BSD_SETJMP: UNICOS configuration for
153 UNICOS 6.1/6.0/5.1/5.0 systems.
154
155 STREAMSPTY: Use /dev/ptmx to get a clean pty. This
156 is for SVr4 derivatives (Like Solaris)
157
158 UTMPX: For systems that have /etc/utmpx. This is for
159 SVr4 derivatives (Like Solaris)
160
161 Definitions for BSDI 1.0
162
163 Definitions for 4.3 Reno and 4.4 BSD.
164
165 Definitions for UNICOS 8.0 and UNICOS 7.C
166
167 Definitions for Solaris 2.0
168
169 Definitions for HP-UX 8.0
170
171 Latest Copyright notices from Berkeley.
172
173 FLOW-CONTROL: support for RFC-XXXx
174
175
176 Client Specific:
177
178 Fix the "send" command to not send garbage...
179
180 Fix status message for "skiprc"
181
182 Make sure to send NAWS after telnet has been suspended
183 or an external command has been run, if the window size
184 has changed.
185
186 sysV88 support.
187
188 Server Specific:
189
190 Support flowcontrol option in non-linemode servers.
191
192 -k Server supports Kludge Linemode, but will default to
193 either single character mode or real Linemode support.
194 The user will have to explicitly ask to switch into
195 kludge linemode. ("stty extproc", or escape back to
196 to telnet and say "mode line".)
197
198 -u Specify the length of the hostname field in the utmp
199 file. Hostname longer than this length will be put
200 into the utmp file in dotted decimal notation, rather
201 than putting in a truncated hostname.
202
203 -U Registered hosts only. If a reverse hostname lookup
204 fails, the connection will be refused.
205
206 -f/-F
207 Allows forwarding of credentials for KRB5.
208
209February 22, 1991:
210
211 Features:
212
213 This version of telnet/telnetd has support for both
214 the AUTHENTICATION and ENCRYPTION options. The
215 AUTHENTICATION option is fairly well defined, and
216 an option number has been assigned to it. The
217 ENCRYPTION option is still in a state of flux; an
218 option number has been assigned to, but it is still
219 subject to change. The code is provided in this release
220 for experimental and testing purposes.
221
222 The telnet "send" command can now be used to send
223 do/dont/will/wont commands, with any telnet option
224 name. The rules for when do/dont/will/wont are sent
225 are still followed, so just because the user requests
226 that one of these be sent doesn't mean that it will
227 be sent...
228
229 The telnet "getstatus" command no longer requires
230 that option printing be enabled to see the response
231 to the "DO STATUS" command.
232
233 A -n flag has been added to telnetd to disable
234 keepalives.
235
236 A new telnet command, "auth" has been added (if
237 AUTHENTICATE is defined). It has four sub-commands,
238 "status", "disable", "enable" and "help".
239
240 A new telnet command, "encrypt" has been added (if
241 ENCRYPT is defined). It has many sub-commands:
242 "enable", "type", "start", "stop", "input",
243 "-input", "output", "-output", "status", and "help".
244
245 The LOGOUT option is now supported by both telnet
246 and telnetd, a new command, "logout", was added
247 to support this.
248
249 Several new toggle options were added:
250 "autoencrypt", "autodecrypt", "autologin", "authdebug",
251 "encdebug", "skiprc", "verbose_encrypt"
252
253 An "rlogin" interface has been added. If the program
254 is named "rlogin", or the "-r" flag is given, then
255 an rlogin type of interface will be used.
256 ~. Terminates the session
257 ~<susp> Suspend the session
258 ~^] Escape to telnet command mode
259 ~~ Pass through the ~.
260 BUG: If you type the rlogin escape character
261 in the middle of a line while in rlogin
262 mode, you cannot erase it or any characters
263 before it. Hopefully this can be fixed
264 in a future release...
265
266 General changes:
267
268 A "libtelnet.a" has now been created. This library
269 contains code that is common to both telnet and
270 telnetd. This is also where library routines that
271 are needed, but are not in the standard C library,
272 are placed.
273
274 The makefiles have been re-done. All of the site
275 specific configuration information has now been put
276 into a single "Config.generic" file, in the top level
277 directory. Changing this one file will take care of
278 all three subdirectories. Also, to add a new/local
279 definition, a "Config.local" file may be created
280 at the top level; if that file exists, the subdirectories
281 will use that file instead of "Config.generic".
282
283 Many 1-2 line functions in commands.c have been
284 removed, and just inserted in-line, or replaced
285 with a macro.
286
287 Bug Fixes:
288
289 The non-termio code in both telnet and telnetd was
290 setting/clearing CTLECH in the sg_flags word. This
291 was incorrect, and has been changed to set/clear the
292 LCTLECH bit in the local mode word.
293
294 The SRCRT #define has been removed. If IP_OPTIONS
295 and IPPROTO_IP are defined on the system, then the
296 source route code is automatically enabled.
297
298 The NO_GETTYTAB #define has been removed; there
299 is a compatibility routine that can be built into
300 libtelnet to achieve the same results.
301
302 The server, telnetd, has been switched to use getopt()
303 for parsing the argument list.
304
305 The code for getting the input/output speeds via
306 cfgetispeed()/cfgetospeed() was still not quite
307 right in telnet. Posix says if the ispeed is 0,
308 then it is really equal to the ospeed.
309
310 The suboption processing code in telnet now has
311 explicit checks to make sure that we received
312 the entire suboption (telnetd was already doing this).
313
314 The telnet code for processing the terminal type
315 could cause a core dump if an existing connection
316 was closed, and a new connection opened without
317 exiting telnet.
318
319 Telnetd was doing a TCSADRAIN when setting the new
320 terminal settings; This is not good, because it means
321 that the tcsetattr() will hang waiting for output to
322 drain, and telnetd is the only one that will drain
323 the output... The fix is to use TCSANOW which does
324 not wait.
325
326 Telnetd was improperly setting/clearing the ISTRIP
327 flag in the c_lflag field, it should be using the
328 c_iflag field.
329
330 When the child process of telnetd was opening the
331 slave side of the pty, it was re-setting the EXTPROC
332 bit too early, and some of the other initialization
333 code was wiping it out. This would cause telnetd
334 to go out of linemode and into single character mode.
335
336 One instance of leaving linemode in telnetd forgot
337 to send a WILL ECHO to the client, the net result
338 would be that the user would see double character
339 echo.
340
341 If the MODE was being changed several times very
342 quickly, telnetd could get out of sync with the
343 state changes and the returning acks; and wind up
344 being left in the wrong state.
345
346September 14, 1990:
347
348 Switch the client to use getopt() for parsing the
349 argument list. The 4.3Reno getopt.c is included for
350 systems that don't have getopt().
351
352 Use the posix _POSIX_VDISABLE value for what value
353 to use when disabling special characters. If this
354 is undefined, it defaults to 0x3ff.
355
356 For non-termio systems, TIOCSETP was being used to
357 change the state of the terminal. This causes the
358 input queue to be flushed, which we don't want. This
359 is now changed to TIOCSETN.
360
361 Take out the "#ifdef notdef" around the code in the
362 server that generates a "sync" when the pty output
363 is flushed. The potential problem is that some older
364 telnet clients may go into an infinite loop when they
365 receive a "sync", if so, the server can be compiled
366 with "NO_URGENT" defined.
367
368 Fix the client where it was setting/clearing the OPOST
369 bit in the c_lflag field, not the c_oflag field.
370
371 Fix the client where it was setting/clearing the ISTRIP
372 bit in the c_lflag field, not the c_iflag field. (On
373 4.3Reno, this is the ECHOPRT bit in the c_lflag field.)
374 The client also had its interpretation of WILL BINARY
375 and DO BINARY reversed.
376
377 Fix a bug in client that would cause a core dump when
378 attempting to remove the last environment variable.
379
380 In the client, there were a few places were switch()
381 was being passed a character, and if it was a negative
382 value, it could get sign extended, and not match
383 the 8 bit case statements. The fix is to and the
384 switch value with 0xff.
385
386 Add a couple more printoption() calls in the client, I
387 don't think there are any more places were a telnet
388 command can be received and not printed out when
389 "options" is on.
390
391 A new flag has been added to the client, "-a". Currently,
392 this just causes the USER name to be sent across, in
393 the future this may be used to signify that automatic
394 authentication is requested.
395
396 The USER variable is now only sent by the client if
397 the "-a" or "-l user" options are explicitly used, or
398 if the user explicitly asks for the "USER" environment
399 variable to be exported. In the server, if it receives
400 the "USER" environment variable, it won't print out the
401 banner message, so that only "Password:" will be printed.
402 This makes the semantics more like rlogin, and should be
403 more familiar to the user. (People are not used to
404 getting a banner message, and then getting just a
405 "Password:" prompt.)
406
407 Re-vamp the code for starting up the child login
408 process. The code was getting ugly, and it was
409 hard to tell what was really going on. What we
410 do now is after the fork(), in the child:
411 1) make sure we have no controlling tty
412 2) open and initialize the tty
413 3) do a setsid()/setpgrp()
414 4) makes the tty our controlling tty.
415 On some systems, #2 makes the tty our controlling
416 tty, and #4 is a no-op. The parent process does
417 a gets rid of any controlling tty after the child
418 is fork()ed.
419
420 Use the strdup() library routine in telnet, instead
421 of the local savestr() routine. If you don't have
422 strdup(), you need to define NO_STRDUP.
423
424 Add support for ^T (SIGINFO/VSTATUS), found in the
425 4.3Reno distribution. This maps to the AYT character.
426 You need a 4-line bugfix in the kernel to get this
427 to work properly:
428
429 > *** tty_pty.c.ORG Tue Sep 11 09:41:53 1990
430 > --- tty_pty.c Tue Sep 11 17:48:03 1990
431 > ***************
432 > *** 609,613 ****
433 > if ((tp->t_lflag&NOFLSH) == 0)
434 > ttyflush(tp, FREAD|FWRITE);
435 > ! pgsignal(tp->t_pgrp, *(unsigned int *)data);
436 > return(0);
437 > }
438 > --- 609,616 ----
439 > if ((tp->t_lflag&NOFLSH) == 0)
440 > ttyflush(tp, FREAD|FWRITE);
441 > ! pgsignal(tp->t_pgrp, *(unsigned int *)data, 1);
442 > ! if ((*(unsigned int *)data == SIGINFO) &&
443 > ! ((tp->t_lflag&NOKERNINFO) == 0))
444 > ! ttyinfo(tp);
445 > return(0);
446 > }
447
448 The client is now smarter when setting the telnet escape
449 character; it only sets it to one of VEOL and VEOL2 if
450 one of them is undefined, and the other one is not already
451 defined to the telnet escape character.
452
453 Handle TERMIOS systems that have separate input and output
454 line speed settings embedded in the flags.
455
456 Many other minor bug fixes.
457
458June 20, 1990:
459 Re-organize makefiles and source tree. The telnet/Source
460 directory is now gone, and all the source that was in
461 telnet/Source is now just in the telnet directory.
462
463 Separate makefile for each system are now gone. There
464 are two makefiles, Makefile and Makefile.generic.
465 The "Makefile" has the definitions for the various
466 system, and "Makefile.generic" does all the work.
467 There is a variable called "WHAT" that is used to
468 specify what to make. For example, in the telnet
469 directory, you might say:
470 make 4.4bsd WHAT=clean
471 to clean out the directory.
472
473 Add support for the ENVIRON and XDISPLOC options.
474 In order for the server to work, login has to have
475 the "-p" option to preserve environment variables.
476
477 Add the SOFT_TAB and LIT_ECHO modes in the LINEMODE support.
478
479 Add the "-l user" option to command line and open command
480 (This is passed through the ENVIRON option).
481
482 Add the "-e" command line option, for setting the escape
483 character.
484
485 Add the "-D", diagnostic, option to the server. This allows
486 the server to print out debug information, which is very
487 useful when trying to debug a telnet that doesn't have any
488 debugging ability.
489
490 Turn off the literal next character when not in LINEMODE.
491
492 Don't recognize ^Y locally, just pass it through.
493
494 Make minor modifications for Sun4.0 and Sun4.1
495
496 Add support for both FORW1 and FORW2 characters. The
497 telnet escape character is set to whichever of the
498 two is not being used. If both are in use, the escape
499 character is not set, so when in linemode the user will
500 have to follow the escape character with a <CR> or <EOF)
501 to get it passed through.
502
503 Commands can now be put in single and double quotes, and
504 a backslash is now an escape character. This is needed
505 for allowing arbitrary strings to be assigned to environment
506 variables.
507
508 Switch telnetd to use macros like telnet for keeping
509 track of the state of all the options.
510
511 Fix telnetd's processing of options so that we always do
512 the right processing of the LINEMODE option, regardless
513 of who initiates the request to turn it on. Also, make
514 sure that if the other side went "WILL ECHO" in response
515 to our "DO ECHO", that we send a "DONT ECHO" to get the
516 option turned back off!
517
518 Fix the TERMIOS setting of the terminal speed to handle both
519 BSD's separate fields, and the SYSV method of CBAUD bits.
520
521 Change how we deal with the other side refusing to enable
522 an option. The sequence used to be: send DO option; receive
523 WONT option; send DONT option. Now, the sequence is: send
524 DO option; receive WONT option. Both should be valid
525 according to the spec, but there has been at least one
526 client implementation of telnet identified that can get
527 really confused by this. (The exact sequence, from a trace
528 on the server side, is (numbers are number of responses that
529 we expect to get after that line...):
530
531 send WILL ECHO 1 (initial request)
532 send WONT ECHO 2 (server is changing state)
533 recv DO ECHO 1 (first reply, ok. expect DONT ECHO next)
534 send WILL ECHO 2 (server changes state again)
535 recv DONT ECHO 1 (second reply, ok. expect DO ECHO next)
536 recv DONT ECHO 0 (third reply, wrong answer. got DONT!!!)
537 *** send WONT ECHO (send WONT to acknowledge the DONT)
538 send WILL ECHO 1 (ask again to enable option)
539 recv DO ECHO 0
540
541 recv DONT ECHO 0
542 send WONT ECHO 1
543 recv DONT ECHO 0
544 recv DO ECHO 1
545 send WILL ECHO 0
546 (and the last 5 lines loop forever)
547
548 The line with the "***" is last of the WILL/DONT/WONT sequence.
549 The change to the server to not generate that makes this same
550 example become:
551
552 send will ECHO 1
553 send wont ECHO 2
554 recv do ECHO 1
555 send will ECHO 2
556 recv dont ECHO 1
557 recv dont ECHO 0
558 recv do ECHO 1
559 send will ECHO 0
560
561 There is other option negotiation going on, and not sending
562 the third part changes some of the timings, but this specific
563 example no longer gets stuck in a loop. The "telnet.state"
564 file has been modified to reflect this change to the algorithm.
565
566 A bunch of miscellaneous bug fixes and changes to make
567 lint happier.
568
569 This version of telnet also has some KERBEROS stuff in
570 it. This has not been tested, it uses an un-authorized
571 telnet option number, and uses an out-of-date version
572 of the (still being defined) AUTHENTICATION option.
573 There is no support for this code, do not enable it.
574
575
576March 1, 1990:
577CHANGES/BUGFIXES SINCE LAST RELEASE:
578 Some support for IP TOS has been added. Requires that the
579 kernel support the IP_TOS socket option (currently this
580 is only in UNICOS 6.0).
581
582 Both telnet and telnetd now use the cc_t typedef. typedefs are
583 included for systems that don't have it (in termios.h).
584
585 SLC_SUSP was not supported properly before. It is now.
586
587 IAC EOF was not translated properly in telnetd for SYSV_TERMIO
588 when not in linemode. It now saves a copy of the VEOF character,
589 so that when ICANON is turned off and we can't trust it anymore
590 (because it is now the VMIN character) we use the saved value.
591
592 There were two missing "break" commands in the linemode
593 processing code in telnetd.
594
595 Telnetd wasn't setting the kernel window size information
596 properly. It was using the rows for both rows and columns...
597
598Questions/comments go to
599 David Borman
600 Cray Research, Inc.
601 655F Lone Oak Drive
602 Eagan, MN 55123
603 dab@cray.com.
604
605README: You are reading it.
606
607Config.generic:
608 This file contains all the OS specific definitions. It
609 has pre-definitions for many common system types, and is
610 in standard makefile format. See the comments at the top
611 of the file for more information.
612
613Config.local:
614 This is not part of the distribution, but if this file exists,
615 it is used instead of "Config.generic". This allows site
616 specific configuration without having to modify the distributed
617 "Config.generic" file.
618
619kern.diff:
620 This file contains the diffs for the changes needed for the
621 kernel to support LINEMODE is the server. These changes are
622 for a 4.3BSD system. You may need to make some changes for
623 your particular system.
624
625 There is a new bit in the terminal state word, TS_EXTPROC.
626 When this bit is set, several aspects of the terminal driver
627 are disabled. Input line editing, character echo, and
628 mapping of signals are all disabled. This allows the telnetd
629 to turn of these functions when in linemode, but still keep
630 track of what state the user wants the terminal to be in.
631
632 New ioctl()s:
633
634 TIOCEXT Turn on/off the TS_EXTPROC bit
635 TIOCGSTATE Get t_state of tty to look at TS_EXTPROC bit
636 TIOCSIG Generate a signal to processes in the
637 current process group of the pty.
638
639 There is a new mode for packet driver, the TIOCPKT_IOCTL bit.
640 When packet mode is turned on in the pty, and the TS_EXTPROC
641 bit is set, then whenever the state of the pty is changed, the
642 next read on the master side of the pty will have the TIOCPKT_IOCTL
643 bit set, and the data will contain the following:
644 struct xx {
645 struct sgttyb a;
646 struct tchars b;
647 struct ltchars c;
648 int t_state;
649 int t_flags;
650 }
651 This allows the process on the server side of the pty to know
652 when the state of the terminal has changed, and what the new
653 state is.
654
655 However, if you define USE_TERMIO or SYSV_TERMIO, the code will
656 expect that the structure returned in the TIOCPKT_IOCTL is
657 the termio/termios structure.
658
659stty.diff:
660 This file contains the changes needed for the stty(1) program
661 to report on the current status of the TS_EXTPROC bit. It also
662 allows the user to turn on/off the TS_EXTPROC bit. This is useful
663 because it allows the user to say "stty -extproc", and the
664 LINEMODE option will be automatically disabled, and saying "stty
665 extproc" will re-enable the LINEMODE option.
666
667telnet.state:
668 Both the client and server have code in them to deal
669 with option negotiation loops. The algorithm that is
670 used is described in this file.
671
672telnet:
673 This directory contains the client code. No kernel changes are
674 needed to use this code.
675
676telnetd:
677 This directory contains the server code. If LINEMODE or KLUDGELINEMODE
678 are defined, then the kernel modifications listed above are needed.
679
680libtelnet:
681 This directory contains code that is common to both the client
682 and the server.
683
684arpa:
685 This directory has a new <arpa/telnet.h>
686
687libtelnet/Makefile.4.4:
688telnet/Makefile.4.4:
689telnetd/Makefile.4.4:
690 These are the makefiles that can be used on a 4.3Reno
691 system when this software is installed in /usr/src/lib/libtelnet,
692 /usr/src/libexec/telnetd, and /usr/src/usr.bin/telnet.
693
694
695The following TELNET options are supported:
696
697 LINEMODE:
698 The LINEMODE option is supported as per RFC1116. The
699 FORWARDMASK option is not currently supported.
700
701 BINARY: The client has the ability to turn on/off the BINARY
702 option in each direction. Turning on BINARY from
703 server to client causes the LITOUT bit to get set in
704 the terminal driver on both ends, turning on BINARY
705 from the client to the server causes the PASS8 bit
706 to get set in the terminal driver on both ends.
707
708 TERMINAL-TYPE:
709 This is supported as per RFC1091. On the server side,
710 when a terminal type is received, termcap/terminfo
711 is consulted to determine if it is a known terminal
712 type. It keeps requesting terminal types until it
713 gets one that it recognizes, or hits the end of the
714 list. The server side looks up the entry in the
715 termcap/terminfo data base, and generates a list of
716 names which it then passes one at a time to each
717 request for a terminal type, duplicating the last
718 entry in the list before cycling back to the beginning.
719
720 NAWS: The Negotiate about Window Size, as per RFC 1073.
721
722 TERMINAL-SPEED:
723 Implemented as per RFC 1079
724
725 TOGGLE-FLOW-CONTROL:
726 Implemented as per RFC 1080
727
728 TIMING-MARK:
729 As per RFC 860
730
731 SGA: As per RFC 858
732
733 ECHO: As per RFC 857
734
735 LOGOUT: As per RFC 727
736
737 STATUS:
738 The server will send its current status upon
739 request. It does not ask for the clients status.
740 The client will request the servers current status
741 from the "send getstatus" command.
742
743 ENVIRON:
744 This option is currently being defined by the IETF
745 Telnet Working Group, and an RFC has not yet been
746 issued, but should be in the near future...
747
748 X-DISPLAY-LOCATION:
749 This functionality can be done through the ENVIRON
750 option, it is added here for completeness.
751
752 AUTHENTICATION:
753 This option is currently being defined by the IETF
754 Telnet Working Group, and an RFC has not yet been
755 issued. The basic framework is pretty much decided,
756 but the definitions for the specific authentication
757 schemes is still in a state of flux.
758
759 ENCRYPTION:
760 This option is currently being defined by the IETF
761 Telnet Working Group, and an RFC has not yet been
762 issued. The draft RFC is still in a state of flux,
763 so this code may change in the future.
764