2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
33 * @(#)state.c 8.5 (Berkeley) 5/30/95
34 * $FreeBSD: src/crypto/telnet/telnetd/state.c,v 1.4.2.3 2002/04/13 10:59:08 markm Exp $
35 * $DragonFly: src/crypto/telnet/telnetd/state.c,v 1.3 2006/01/17 23:50:35 dillon Exp $
41 #include <libtelnet/auth.h>
44 #include <libtelnet/encrypt.h>
47 unsigned char doopt[] = { IAC, DO, '%', 'c', 0 };
48 unsigned char dont[] = { IAC, DONT, '%', 'c', 0 };
49 unsigned char will[] = { IAC, WILL, '%', 'c', 0 };
50 unsigned char wont[] = { IAC, WONT, '%', 'c', 0 };
54 * Buffer for sub-options, and macros
55 * for suboptions buffer manipulations
57 unsigned char subbuffer[512], *subpointer= subbuffer, *subend= subbuffer;
59 #define SB_CLEAR() subpointer = subbuffer
60 #define SB_TERM() { subend = subpointer; SB_CLEAR(); }
61 #define SB_ACCUM(c) if (subpointer < (subbuffer+sizeof subbuffer)) { \
62 *subpointer++ = (c); \
64 #define SB_GET() ((*subpointer++)&0xff)
65 #define SB_EOF() (subpointer >= subend)
66 #define SB_LEN() (subend - subpointer)
69 unsigned char *subsave;
70 #define SB_SAVE() subsave = subpointer;
71 #define SB_RESTORE() subpointer = subsave;
78 #define TS_DATA 0 /* base state */
79 #define TS_IAC 1 /* look for double IAC's */
80 #define TS_CR 2 /* CR-LF ->'s CR */
81 #define TS_SB 3 /* throw away begin's... */
82 #define TS_SE 4 /* ...end's (suboption negotiation) */
83 #define TS_WILL 5 /* will option negotiation */
84 #define TS_WONT 6 /* wont " */
85 #define TS_DO 7 /* do " */
86 #define TS_DONT 8 /* dont " */
88 static void doclientstat(void);
94 static int state = TS_DATA;
97 if ((&ptyobuf[BUFSIZ] - pfrontp) < 2)
99 c = *netip++ & 0377, ncc--;
102 c = (*decrypt_input)(c);
103 #endif /* ENCRYPTION */
108 /* Strip off \n or \0 after a \r */
109 if ((c == 0) || (c == '\n')) {
120 * We now map \r\n ==> \r for pragmatic reasons.
121 * Many client implementations send \r\n when
122 * the user hits the CarriageReturn key.
124 * We USED to map \r\n ==> \n, since \r\n says
125 * that we want to be in column 1 of the next
126 * printable line, and \n is the standard
127 * unix way of saying that (\r is only good
128 * if CRMOD is set, which it normally is).
130 if ((c == '\r') && his_state_is_wont(TELOPT_BINARY)) {
134 nc = (*decrypt_input)(nc & 0xff);
135 #endif /* ENCRYPTION */
138 * If we are operating in linemode,
139 * convert to local end-of-line.
141 if (linemode && (ncc > 0) && (('\n' == nc) ||
142 ((0 == nc) && tty_iscrnl())) ) {
150 (void)(*decrypt_input)(-1);
151 #endif /* ENCRYPTION */
162 * Send the process on the pty side an
163 * interrupt. Do this with a NULL or
164 * interrupt char; depending on the tty mode.
168 printoption("td: recv IAC", c));
174 printoption("td: recv IAC", c));
183 printoption("td: recv IAC", c));
193 printoption("td: recv IAC", c));
194 ptyflush(); /* half-hearted */
197 if (slctab[SLC_AO].sptr &&
198 *slctab[SLC_AO].sptr != (cc_t)(_POSIX_VDISABLE)) {
200 (unsigned char)*slctab[SLC_AO].sptr;
203 netclear(); /* clear buffer back */
204 output_data("%c%c", IAC, DM);
205 neturg = nfrontp-1; /* off by one XXX */
207 printoption("td: send IAC", DM));
212 * Erase Character and
221 printoption("td: recv IAC", c));
222 ptyflush(); /* half-hearted */
225 ch = *slctab[SLC_EC].sptr;
227 ch = *slctab[SLC_EL].sptr;
228 if (ch != (cc_t)(_POSIX_VDISABLE))
229 *pfrontp++ = (unsigned char)ch;
234 * Check for urgent data...
238 printoption("td: recv IAC", c));
239 SYNCHing = stilloob(net);
245 * Begin option subnegotiation...
268 if (his_state_is_will(TELOPT_EOR))
273 * Handle RFC 10xx Telnet linemode option additions
274 * to command stream (EOF, SUSP, ABORT).
307 * bad form of suboption negotiation.
308 * handle it in such a way as to avoid
309 * damage to local state. Parse
310 * suboption buffer found so far,
311 * then treat remaining stream as
312 * another command sequence.
315 /* for DIAGNOSTICS */
328 /* for DIAGNOSTICS */
334 suboption(); /* handle sub-option */
360 syslog(LOG_ERR, "panic state=%d", state);
361 printf("telnetd: panic state=%d\n", state);
365 } /* end of telrcv */
368 * The will/wont/do/dont state machines are based on Dave Borman's
369 * Telnet option processing state machine.
371 * These correspond to the following states:
372 * my_state = the last negotiated state
373 * want_state = what I want the state to go to
374 * want_resp = how many requests I have sent
375 * All state defaults are negative, and resp defaults to 0.
377 * When initiating a request to change state to new_state:
379 * if ((want_resp == 0 && new_state == my_state) || want_state == new_state) {
382 * want_state = new_state;
387 * When receiving new_state:
391 * if (want_resp && (new_state == my_state))
394 * if ((want_resp == 0) && (new_state != want_state)) {
395 * if (ok_to_switch_to new_state)
396 * want_state = new_state;
401 * my_state = new_state;
403 * Note that new_state is implied in these functions by the function itself.
404 * will and do imply positive new_state, wont and dont imply negative.
406 * Finally, there is one catch. If we send a negative response to a
407 * positive request, my_state will be the positive while want_state will
408 * remain negative. my_state will revert to negative when the negative
409 * acknowlegment arrives from the peer. Thus, my_state generally tells
410 * us not only the last negotiated state, but also tells us what the peer
411 * wants to be doing as well. It is important to understand this difference
412 * as we may wish to be processing data streams based on our desired state
413 * (want_state) or based on what the peer thinks the state is (my_state).
415 * This all works fine because if the peer sends a positive request, the data
416 * that we receive prior to negative acknowlegment will probably be affected
417 * by the positive state, and we can process it as such (if we can; if we
418 * can't then it really doesn't matter). If it is that important, then the
419 * peer probably should be buffering until this option state negotiation
424 send_do(int option, int init)
427 if ((do_dont_resp[option] == 0 && his_state_is_will(option)) ||
428 his_want_state_is_will(option))
431 * Special case for TELOPT_TM: We send a DO, but pretend
432 * that we sent a DONT, so that we can send more DOs if
435 if (option == TELOPT_TM)
436 set_his_want_state_wont(option);
438 set_his_want_state_will(option);
439 do_dont_resp[option]++;
441 output_data((const char *)doopt, option);
443 DIAG(TD_OPTIONS, printoption("td: send do", option));
447 willoption(int option)
450 void (*func)(void) = 0;
453 * process input from peer.
456 DIAG(TD_OPTIONS, printoption("td: recv will", option));
458 if (do_dont_resp[option]) {
459 do_dont_resp[option]--;
460 if (do_dont_resp[option] && his_state_is_will(option))
461 do_dont_resp[option]--;
463 if (do_dont_resp[option] == 0) {
464 if (his_want_state_is_wont(option)) {
476 * See comments below for more info.
478 not42 = 0; /* looks like a 4.2 system */
482 #if defined(LINEMODE) && defined(KLUDGELINEMODE)
484 * This telnetd implementation does not really
485 * support timing marks, it just uses them to
486 * support the kludge linemode stuff. If we
487 * receive a will or wont TM in response to our
488 * do TM request that may have been sent to
489 * determine kludge linemode support, process
490 * it, otherwise TM should get a negative
494 * Handle the linemode kludge stuff.
495 * If we are not currently supporting any
496 * linemode at all, then we assume that this
497 * is the client telling us to use kludge
498 * linemode in response to our query. Set the
499 * linemode type that is to be supported, note
500 * that the client wishes to use linemode, and
501 * eat the will TM as though it never arrived.
503 if (lmodetype < KLUDGE_LINEMODE) {
504 lmodetype = KLUDGE_LINEMODE;
505 clientstat(TELOPT_LINEMODE, WILL, 0);
506 send_wont(TELOPT_SGA, 1);
507 } else if (lmodetype == NO_AUTOKLUDGE) {
508 lmodetype = KLUDGE_OK;
510 #endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
512 * We never respond to a WILL TM, and
513 * we leave the state WONT.
519 * If we are going to support flow control
520 * option, then don't worry peer that we can't
521 * change the flow control characters.
523 slctab[SLC_XON].defset.flag &= ~SLC_LEVELBITS;
524 slctab[SLC_XON].defset.flag |= SLC_DEFAULT;
525 slctab[SLC_XOFF].defset.flag &= ~SLC_LEVELBITS;
526 slctab[SLC_XOFF].defset.flag |= SLC_DEFAULT;
531 case TELOPT_XDISPLOC:
532 case TELOPT_NEW_ENVIRON:
533 case TELOPT_OLD_ENVIRON:
538 case TELOPT_LINEMODE:
539 # ifdef KLUDGELINEMODE
541 * Note client's desire to use linemode.
543 lmodetype = REAL_LINEMODE;
544 # endif /* KLUDGELINEMODE */
548 #endif /* LINEMODE */
550 #ifdef AUTHENTICATION
551 case TELOPT_AUTHENTICATION:
559 func = encrypt_send_support;
562 #endif /* ENCRYPTION */
568 set_his_want_state_will(option);
571 do_dont_resp[option]++;
572 send_dont(option, 0);
576 * Option processing that should happen when
577 * we receive conformation of a change in
578 * state that we had requested.
582 not42 = 0; /* looks like a 4.2 system */
584 * Egads, he responded "WILL ECHO". Turn
587 send_dont(option, 1);
589 * "WILL ECHO". Kludge upon kludge!
590 * A 4.2 client is now echoing user input at
591 * the tty. This is probably undesireable and
592 * it should be stopped. The client will
593 * respond WONT TM to the DO TM that we send to
594 * check for kludge linemode. When the WONT TM
595 * arrives, linemode will be turned off and a
596 * change propogated to the pty. This change
597 * will cause us to process the new pty state
598 * in localstat(), which will notice that
599 * linemode is off and send a WILL ECHO
600 * so that we are properly in character mode and
605 case TELOPT_LINEMODE:
606 # ifdef KLUDGELINEMODE
608 * Note client's desire to use linemode.
610 lmodetype = REAL_LINEMODE;
611 # endif /* KLUDGELINEMODE */
614 #endif /* LINEMODE */
616 #ifdef AUTHENTICATION
617 case TELOPT_AUTHENTICATION:
624 func = encrypt_send_support;
626 #endif /* ENCRYPTION */
633 set_his_state_will(option);
636 } /* end of willoption */
639 send_dont(int option, int init)
642 if ((do_dont_resp[option] == 0 && his_state_is_wont(option)) ||
643 his_want_state_is_wont(option))
645 set_his_want_state_wont(option);
646 do_dont_resp[option]++;
648 output_data((const char *)dont, option);
650 DIAG(TD_OPTIONS, printoption("td: send dont", option));
654 wontoption(int option)
657 * Process client input.
660 DIAG(TD_OPTIONS, printoption("td: recv wont", option));
662 if (do_dont_resp[option]) {
663 do_dont_resp[option]--;
664 if (do_dont_resp[option] && his_state_is_wont(option))
665 do_dont_resp[option]--;
667 if (do_dont_resp[option] == 0) {
668 if (his_want_state_is_will(option)) {
669 /* it is always ok to change to negative state */
672 not42 = 1; /* doesn't seem to be a 4.2 system */
682 case TELOPT_LINEMODE:
683 # ifdef KLUDGELINEMODE
685 * If real linemode is supported, then client is
686 * asking to turn linemode off.
688 if (lmodetype != REAL_LINEMODE)
690 lmodetype = KLUDGE_LINEMODE;
691 # endif /* KLUDGELINEMODE */
692 clientstat(TELOPT_LINEMODE, WONT, 0);
694 #endif /* LINEMODE */
698 * If we get a WONT TM, and had sent a DO TM,
699 * don't respond with a DONT TM, just leave it
700 * as is. Short circut the state machine to
703 set_his_want_state_wont(TELOPT_TM);
708 * If we are not going to support flow control
709 * option, then let peer know that we can't
710 * change the flow control characters.
712 slctab[SLC_XON].defset.flag &= ~SLC_LEVELBITS;
713 slctab[SLC_XON].defset.flag |= SLC_CANTCHANGE;
714 slctab[SLC_XOFF].defset.flag &= ~SLC_LEVELBITS;
715 slctab[SLC_XOFF].defset.flag |= SLC_CANTCHANGE;
718 #ifdef AUTHENTICATION
719 case TELOPT_AUTHENTICATION:
720 auth_finished(0, AUTH_REJECT);
725 * For options that we might spin waiting for
726 * sub-negotiation, if the client turns off the
727 * option rather than responding to the request,
728 * we have to treat it here as if we got a response
729 * to the sub-negotiation, (by updating the timers)
730 * so that we'll break out of the loop.
733 settimer(ttypesubopt);
737 settimer(tspeedsubopt);
740 case TELOPT_XDISPLOC:
741 settimer(xdisplocsubopt);
744 case TELOPT_OLD_ENVIRON:
745 settimer(oenvironsubopt);
748 case TELOPT_NEW_ENVIRON:
749 settimer(environsubopt);
755 set_his_want_state_wont(option);
756 if (his_state_is_will(option))
757 send_dont(option, 0);
761 #if defined(LINEMODE) && defined(KLUDGELINEMODE)
762 if (lmodetype < NO_AUTOKLUDGE) {
763 lmodetype = NO_LINEMODE;
764 clientstat(TELOPT_LINEMODE, WONT, 0);
765 send_will(TELOPT_SGA, 1);
766 send_will(TELOPT_ECHO, 1);
768 #endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
771 #ifdef AUTHENTICATION
772 case TELOPT_AUTHENTICATION:
773 auth_finished(0, AUTH_REJECT);
781 set_his_state_wont(option);
783 } /* end of wontoption */
786 send_will(int option, int init)
789 if ((will_wont_resp[option] == 0 && my_state_is_will(option))||
790 my_want_state_is_will(option))
792 set_my_want_state_will(option);
793 will_wont_resp[option]++;
795 output_data((const char *)will, option);
797 DIAG(TD_OPTIONS, printoption("td: send will", option));
800 #if !defined(LINEMODE) || !defined(KLUDGELINEMODE)
802 * When we get a DONT SGA, we will try once to turn it
803 * back on. If the other side responds DONT SGA, we
804 * leave it at that. This is so that when we talk to
805 * clients that understand KLUDGELINEMODE but not LINEMODE,
806 * we'll keep them in char-at-a-time mode.
817 * Process client input.
820 DIAG(TD_OPTIONS, printoption("td: recv do", option));
822 if (will_wont_resp[option]) {
823 will_wont_resp[option]--;
824 if (will_wont_resp[option] && my_state_is_will(option))
825 will_wont_resp[option]--;
827 if ((will_wont_resp[option] == 0) && (my_want_state_is_wont(option))) {
831 # ifdef KLUDGELINEMODE
832 if (lmodetype == NO_LINEMODE)
834 if (his_state_is_wont(TELOPT_LINEMODE))
853 #if defined(LINEMODE) && defined(KLUDGELINEMODE)
855 * If kludge linemode is in use, then we must
856 * process an incoming do SGA for linemode
859 if (lmodetype == KLUDGE_LINEMODE) {
861 * Receipt of "do SGA" in kludge
862 * linemode is the peer asking us to
863 * turn off linemode. Make note of
866 clientstat(TELOPT_LINEMODE, WONT, 0);
868 * If linemode did not get turned off
869 * then don't tell peer that we did.
870 * Breaking here forces a wont SGA to
878 #endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
888 * Special case for TM. We send a WILL, but
889 * pretend we sent a WONT.
891 send_will(option, 0);
892 set_my_want_state_wont(option);
893 set_my_state_wont(option);
898 * When we get a LOGOUT option, respond
899 * with a WILL LOGOUT, make sure that
900 * it gets written out to the network,
901 * and then just go away...
903 set_my_want_state_will(TELOPT_LOGOUT);
904 send_will(TELOPT_LOGOUT, 0);
905 set_my_state_will(TELOPT_LOGOUT);
915 #endif /* ENCRYPTION */
916 case TELOPT_LINEMODE:
921 case TELOPT_XDISPLOC:
922 #ifdef TELOPT_ENVIRON
923 case TELOPT_NEW_ENVIRON:
925 case TELOPT_OLD_ENVIRON:
930 set_my_want_state_will(option);
931 send_will(option, 0);
933 will_wont_resp[option]++;
934 send_wont(option, 0);
937 set_my_state_will(option);
939 } /* end of dooption */
942 send_wont(int option, int init)
945 if ((will_wont_resp[option] == 0 && my_state_is_wont(option)) ||
946 my_want_state_is_wont(option))
948 set_my_want_state_wont(option);
949 will_wont_resp[option]++;
951 output_data((const char *)wont, option);
953 DIAG(TD_OPTIONS, printoption("td: send wont", option));
957 dontoption(int option)
960 * Process client input.
964 DIAG(TD_OPTIONS, printoption("td: recv dont", option));
966 if (will_wont_resp[option]) {
967 will_wont_resp[option]--;
968 if (will_wont_resp[option] && my_state_is_wont(option))
969 will_wont_resp[option]--;
971 if ((will_wont_resp[option] == 0) && (my_want_state_is_will(option))) {
979 case TELOPT_ECHO: /* we should stop echoing */
981 # ifdef KLUDGELINEMODE
982 if ((lmodetype != REAL_LINEMODE) &&
983 (lmodetype != KLUDGE_LINEMODE))
985 if (his_state_is_wont(TELOPT_LINEMODE))
996 #if defined(LINEMODE) && defined(KLUDGELINEMODE)
998 * If kludge linemode is in use, then we
999 * must process an incoming do SGA for
1000 * linemode purposes.
1002 if ((lmodetype == KLUDGE_LINEMODE) ||
1003 (lmodetype == KLUDGE_OK)) {
1005 * The client is asking us to turn
1008 lmodetype = KLUDGE_LINEMODE;
1009 clientstat(TELOPT_LINEMODE, WILL, 0);
1011 * If we did not turn line mode on,
1012 * then what do we say? Will SGA?
1013 * This violates design of telnet.
1014 * Gross. Very Gross.
1019 set_my_want_state_wont(option);
1020 if (my_state_is_will(option))
1021 send_wont(option, 0);
1022 set_my_state_wont(option);
1023 if (turn_on_sga ^= 1)
1024 send_will(option, 1);
1026 #endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
1032 set_my_want_state_wont(option);
1033 if (my_state_is_will(option))
1034 send_wont(option, 0);
1036 set_my_state_wont(option);
1038 } /* end of dontoption */
1042 int env_ovalue = -1;
1043 #else /* ENV_HACK */
1044 # define env_ovar OLD_ENV_VAR
1045 # define env_ovalue OLD_ENV_VALUE
1046 #endif /* ENV_HACK */
1051 * Look at the sub-option buffer, and try to be helpful to the other
1054 * Currently we recognize:
1066 DIAG(TD_OPTIONS, {netflush(); printsub('<', subpointer, SB_LEN()+2);});
1070 case TELOPT_TSPEED: {
1073 if (his_state_is_wont(TELOPT_TSPEED)) /* Ignore if option disabled */
1076 settimer(tspeedsubopt);
1078 if (SB_EOF() || SB_GET() != TELQUAL_IS)
1081 xspeed = atoi((char *)subpointer);
1083 while (SB_GET() != ',' && !SB_EOF());
1087 rspeed = atoi((char *)subpointer);
1088 clientstat(TELOPT_TSPEED, xspeed, rspeed);
1092 } /* end of case TELOPT_TSPEED */
1094 case TELOPT_TTYPE: { /* Yaaaay! */
1095 static char terminalname[TERMINAL_TYPE_SIZE];
1097 if (his_state_is_wont(TELOPT_TTYPE)) /* Ignore if option disabled */
1099 settimer(ttypesubopt);
1101 if (SB_EOF() || SB_GET() != TELQUAL_IS) {
1102 return; /* ??? XXX but, this is the most robust */
1105 terminaltype = terminalname;
1107 while ((terminaltype < (terminalname + sizeof terminalname-1)) &&
1115 *terminaltype++ = c; /* accumulate name */
1118 terminaltype = terminalname;
1120 } /* end of case TELOPT_TTYPE */
1123 int xwinsize, ywinsize;
1125 if (his_state_is_wont(TELOPT_NAWS)) /* Ignore if option disabled */
1130 xwinsize = SB_GET() << 8;
1133 xwinsize |= SB_GET();
1136 ywinsize = SB_GET() << 8;
1139 ywinsize |= SB_GET();
1140 clientstat(TELOPT_NAWS, xwinsize, ywinsize);
1144 } /* end of case TELOPT_NAWS */
1147 case TELOPT_LINEMODE: {
1150 if (his_state_is_wont(TELOPT_LINEMODE)) /* Ignore if option disabled */
1153 * Process linemode suboptions.
1156 break; /* garbage was sent */
1157 request = SB_GET(); /* get will/wont */
1160 break; /* another garbage check */
1162 if (request == LM_SLC) { /* SLC is not preceeded by WILL or WONT */
1164 * Process suboption buffer of slc's
1167 do_opt_slc(subpointer, subend - subpointer);
1170 } else if (request == LM_MODE) {
1173 useeditmode = SB_GET(); /* get mode flag */
1174 clientstat(LM_MODE, 0, 0);
1180 switch (SB_GET()) { /* what suboption? */
1181 case LM_FORWARDMASK:
1183 * According to spec, only server can send request for
1184 * forwardmask, and client can only return a positive response.
1185 * So don't worry about it.
1192 } /* end of case TELOPT_LINEMODE */
1194 case TELOPT_STATUS: {
1202 if (my_state_is_will(TELOPT_STATUS))
1213 } /* end of case TELOPT_STATUS */
1215 case TELOPT_XDISPLOC: {
1216 if (SB_EOF() || SB_GET() != TELQUAL_IS)
1218 settimer(xdisplocsubopt);
1219 subpointer[SB_LEN()] = '\0';
1220 (void)setenv("DISPLAY", (char *)subpointer, 1);
1222 } /* end of case TELOPT_XDISPLOC */
1224 #ifdef TELOPT_NEW_ENVIRON
1225 case TELOPT_NEW_ENVIRON:
1227 case TELOPT_OLD_ENVIRON: {
1229 char *cp, *varp, *valp;
1234 if (c == TELQUAL_IS) {
1235 if (subchar == TELOPT_OLD_ENVIRON)
1236 settimer(oenvironsubopt);
1238 settimer(environsubopt);
1239 } else if (c != TELQUAL_INFO) {
1243 #ifdef TELOPT_NEW_ENVIRON
1244 if (subchar == TELOPT_NEW_ENVIRON) {
1247 if ((c == NEW_ENV_VAR) || (c == ENV_USERVAR))
1255 * We only want to do this if we haven't already decided
1256 * whether or not the other side has its VALUE and VAR
1260 int last = -1; /* invalid value */
1262 int got_var = 0, got_value = 0, got_uservar = 0;
1265 * The other side might have its VALUE and VAR values
1266 * reversed. To be interoperable, we need to determine
1267 * which way it is. If the first recognized character
1268 * is a VAR or VALUE, then that will tell us what
1269 * type of client it is. If the fist recognized
1270 * character is a USERVAR, then we continue scanning
1271 * the suboption looking for two consecutive
1272 * VAR or VALUE fields. We should not get two
1273 * consecutive VALUE fields, so finding two
1274 * consecutive VALUE or VAR fields will tell us
1275 * what the client is.
1282 if (last < 0 || last == OLD_ENV_VAR
1283 || (empty && (last == OLD_ENV_VALUE)))
1289 if (last < 0 || last == OLD_ENV_VALUE
1290 || (empty && (last == OLD_ENV_VAR)))
1291 goto env_ovar_wrong;
1293 last = OLD_ENV_VALUE;
1296 /* count strings of USERVAR as one */
1297 if (last != ENV_USERVAR)
1300 if (last == OLD_ENV_VALUE)
1302 if (last == OLD_ENV_VAR)
1303 goto env_ovar_wrong;
1318 if (last == OLD_ENV_VALUE)
1320 if (last == OLD_ENV_VAR)
1321 goto env_ovar_wrong;
1324 * Ok, the first thing was a USERVAR, and there
1325 * are not two consecutive VAR or VALUE commands,
1326 * and none of the VAR or VALUE commands are empty.
1327 * If the client has sent us a well-formed option,
1328 * then the number of VALUEs received should always
1329 * be less than or equal to the number of VARs and
1330 * USERVARs received.
1332 * If we got exactly as many VALUEs as VARs and
1333 * USERVARs, the client has the same definitions.
1335 * If we got exactly as many VARs as VALUEs and
1336 * USERVARS, the client has reversed definitions.
1338 if (got_uservar + got_var == got_value) {
1340 env_ovar = OLD_ENV_VAR;
1341 env_ovalue = OLD_ENV_VALUE;
1342 } else if (got_uservar + got_value == got_var) {
1344 env_ovar = OLD_ENV_VALUE;
1345 env_ovalue = OLD_ENV_VAR;
1347 output_data("ENVIRON VALUE and VAR are reversed!\r\n"));
1356 if ((c == env_ovar) || (c == ENV_USERVAR))
1364 cp = varp = (char *)subpointer;
1369 if (subchar == TELOPT_OLD_ENVIRON) {
1372 else if (c == env_ovalue)
1379 cp = valp = (char *)subpointer;
1386 (void)setenv(varp, valp, 1);
1389 cp = varp = (char *)subpointer;
1405 (void)setenv(varp, valp, 1);
1409 } /* end of case TELOPT_NEW_ENVIRON */
1410 #ifdef AUTHENTICATION
1411 case TELOPT_AUTHENTICATION:
1418 * These are sent by us and cannot be sent by
1423 auth_is(subpointer, SB_LEN());
1426 auth_name(subpointer, SB_LEN());
1432 case TELOPT_ENCRYPT:
1436 case ENCRYPT_SUPPORT:
1437 encrypt_support(subpointer, SB_LEN());
1440 encrypt_is(subpointer, SB_LEN());
1443 encrypt_reply(subpointer, SB_LEN());
1446 encrypt_start(subpointer, SB_LEN());
1451 case ENCRYPT_REQSTART:
1452 encrypt_request_start(subpointer, SB_LEN());
1454 case ENCRYPT_REQEND:
1456 * We can always send an REQEND so that we cannot
1457 * get stuck encrypting. We should only get this
1458 * if we have been able to get in the correct mode
1461 encrypt_request_end();
1463 case ENCRYPT_ENC_KEYID:
1464 encrypt_enc_keyid(subpointer, SB_LEN());
1466 case ENCRYPT_DEC_KEYID:
1467 encrypt_dec_keyid(subpointer, SB_LEN());
1473 #endif /* ENCRYPTION */
1477 } /* end of switch */
1479 } /* end of suboption */
1484 clientstat(TELOPT_LINEMODE, WILL, 0);
1487 #define ADD(c) *ncp++ = c
1488 #define ADD_DATA(c) { *ncp++ = c; if (c == SE || c == IAC) *ncp++ = c; }
1492 unsigned char statusbuf[256];
1498 netflush(); /* get rid of anything waiting to go out */
1506 * We check the want_state rather than the current state,
1507 * because if we received a DO/WILL for an option that we
1508 * don't support, and the other side didn't send a DONT/WONT
1509 * in response to our WONT/DONT, then the "state" will be
1510 * WILL/DO, and the "want_state" will be WONT/DONT. We
1511 * need to go by the latter.
1513 for (i = 0; i < (unsigned char)NTELOPTS; i++) {
1514 if (my_want_state_is_will(i)) {
1520 if (his_want_state_is_will(i)) {
1528 if (his_want_state_is_will(TELOPT_LFLOW)) {
1538 if (restartany >= 0) {
1542 ADD(LFLOW_RESTART_ANY);
1544 ADD(LFLOW_RESTART_XON);
1551 if (his_want_state_is_will(TELOPT_LINEMODE)) {
1552 unsigned char *cp, *cpe;
1556 ADD(TELOPT_LINEMODE);
1562 ADD(TELOPT_LINEMODE);
1567 for (cpe = cp + len; cp < cpe; cp++)
1571 #endif /* LINEMODE */
1576 output_datalen(statusbuf, ncp - statusbuf);
1577 netflush(); /* Send it on its way */
1580 {printsub('>', statusbuf, ncp - statusbuf); netflush();});
1584 * This function appends data to nfrontp and advances nfrontp.
1585 * Returns the number of characters written altogether (the
1586 * buffer may have been flushed in the process).
1590 output_data(const char *format, ...)
1596 va_start(args, format);
1597 if ((len = vasprintf(&buf, format, args)) == -1)
1599 output_datalen(buf, len);
1606 output_datalen(const char *buf, int len)
1608 int remaining, copied;
1610 remaining = BUFSIZ - (nfrontp - netobuf);
1612 /* Free up enough space if the room is too low*/
1613 if ((len > BUFSIZ ? BUFSIZ : len) > remaining) {
1615 remaining = BUFSIZ - (nfrontp - netobuf);
1618 /* Copy out as much as will fit */
1619 copied = remaining > len ? len : remaining;
1620 memmove(nfrontp, buf, copied);
1623 remaining -= copied;