Commit | Line | Data |
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8c5eec2f | 1 | /* |
897ce52e KB |
2 | * Copyright (c) 1983, 1986 Regents of the University of California. |
3 | * All rights reserved. | |
4 | * | |
5 | * Redistribution and use in source and binary forms are permitted | |
b8c620d6 KB |
6 | * provided that the above copyright notice and this paragraph are |
7 | * duplicated in all such forms and that any documentation, | |
8 | * advertising materials, and other materials related to such | |
9 | * distribution and use acknowledge that the software was developed | |
10 | * by the University of California, Berkeley. The name of the | |
11 | * University may not be used to endorse or promote products derived | |
12 | * from this software without specific prior written permission. | |
13 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR | |
14 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED | |
15 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. | |
8c5eec2f DF |
16 | */ |
17 | ||
18 | #ifndef lint | |
19 | char copyright[] = | |
897ce52e | 20 | "@(#) Copyright (c) 1983, 1986 Regents of the University of California.\n\ |
8c5eec2f | 21 | All rights reserved.\n"; |
897ce52e | 22 | #endif /* not lint */ |
8c5eec2f | 23 | |
ac6e6727 | 24 | #ifndef lint |
c847f2e1 | 25 | static char sccsid[] = "@(#)telnetd.c 5.30 (Berkeley) %G%"; |
897ce52e | 26 | #endif /* not lint */ |
ac6e6727 | 27 | |
66b878f6 | 28 | /* |
5eddff6d | 29 | * Telnet server. |
66b878f6 | 30 | */ |
5eddff6d | 31 | #include <sys/param.h> |
de3b21e8 | 32 | #include <sys/socket.h> |
ce4fd43b | 33 | #include <sys/wait.h> |
1a33b848 | 34 | #include <sys/file.h> |
c29f876c | 35 | #include <sys/stat.h> |
5d78ef73 | 36 | #include <sys/time.h> |
de3b21e8 SL |
37 | |
38 | #include <netinet/in.h> | |
39 | ||
2b597a6b SL |
40 | #include <arpa/telnet.h> |
41 | ||
66b878f6 BJ |
42 | #include <stdio.h> |
43 | #include <signal.h> | |
44 | #include <errno.h> | |
45 | #include <sgtty.h> | |
9f005877 | 46 | #include <netdb.h> |
3f99c0f7 | 47 | #include <syslog.h> |
affdaa4e | 48 | #include <ctype.h> |
de3b21e8 | 49 | |
d8b5e42c GM |
50 | #define OPT_NO 0 /* won't do this option */ |
51 | #define OPT_YES 1 /* will do this option */ | |
52 | #define OPT_YES_BUT_ALWAYS_LOOK 2 | |
53 | #define OPT_NO_BUT_ALWAYS_LOOK 3 | |
66b878f6 BJ |
54 | char hisopts[256]; |
55 | char myopts[256]; | |
56 | ||
57 | char doopt[] = { IAC, DO, '%', 'c', 0 }; | |
58 | char dont[] = { IAC, DONT, '%', 'c', 0 }; | |
59 | char will[] = { IAC, WILL, '%', 'c', 0 }; | |
60 | char wont[] = { IAC, WONT, '%', 'c', 0 }; | |
61 | ||
62 | /* | |
63 | * I/O data buffers, pointers, and counters. | |
64 | */ | |
65 | char ptyibuf[BUFSIZ], *ptyip = ptyibuf; | |
affdaa4e | 66 | |
66b878f6 | 67 | char ptyobuf[BUFSIZ], *pfrontp = ptyobuf, *pbackp = ptyobuf; |
affdaa4e | 68 | |
66b878f6 | 69 | char netibuf[BUFSIZ], *netip = netibuf; |
affdaa4e GM |
70 | #define NIACCUM(c) { *netip++ = c; \ |
71 | ncc++; \ | |
72 | } | |
73 | ||
9ef3087d | 74 | char netobuf[BUFSIZ], *nfrontp = netobuf, *nbackp = netobuf; |
5d78ef73 | 75 | char *neturg = 0; /* one past last bye of urgent data */ |
affdaa4e GM |
76 | /* the remote system seems to NOT be an old 4.2 */ |
77 | int not42 = 1; | |
78 | ||
d0a64c71 | 79 | #define BANNER "\r\n\r\n4.3 BSD UNIX (%s)\r\n\r\r\n\r" |
10dc182f | 80 | |
d8b5e42c GM |
81 | /* buffer for sub-options */ |
82 | char subbuffer[100], *subpointer= subbuffer, *subend= subbuffer; | |
affdaa4e | 83 | #define SB_CLEAR() subpointer = subbuffer; |
d8b5e42c | 84 | #define SB_TERM() { subend = subpointer; SB_CLEAR(); } |
affdaa4e GM |
85 | #define SB_ACCUM(c) if (subpointer < (subbuffer+sizeof subbuffer)) { \ |
86 | *subpointer++ = (c); \ | |
87 | } | |
d8b5e42c GM |
88 | #define SB_GET() ((*subpointer++)&0xff) |
89 | #define SB_EOF() (subpointer >= subend) | |
affdaa4e | 90 | |
66b878f6 BJ |
91 | int pcc, ncc; |
92 | ||
93 | int pty, net; | |
94 | int inter; | |
fe5c5547 | 95 | extern char **environ; |
66b878f6 | 96 | extern int errno; |
c29f876c | 97 | char *line; |
5d78ef73 GM |
98 | int SYNCHing = 0; /* we are in TELNET SYNCH mode */ |
99 | /* | |
100 | * The following are some clocks used to decide how to interpret | |
101 | * the relationship between various variables. | |
102 | */ | |
66b878f6 | 103 | |
5d78ef73 GM |
104 | struct { |
105 | int | |
106 | system, /* what the current time is */ | |
107 | echotoggle, /* last time user entered echo character */ | |
108 | modenegotiated, /* last time operating mode negotiated */ | |
109 | didnetreceive, /* last time we read data from network */ | |
d8b5e42c GM |
110 | ttypeopt, /* ttype will/won't received */ |
111 | ttypesubopt, /* ttype subopt is received */ | |
112 | getterminal, /* time started to get terminal information */ | |
5d78ef73 GM |
113 | gotDM; /* when did we last see a data mark */ |
114 | } clocks; | |
115 | ||
d8b5e42c GM |
116 | #define settimer(x) (clocks.x = ++clocks.system) |
117 | #define sequenceIs(x,y) (clocks.x < clocks.y) | |
5d78ef73 | 118 | \f |
66b878f6 BJ |
119 | main(argc, argv) |
120 | char *argv[]; | |
121 | { | |
bb933cc2 | 122 | struct sockaddr_in from; |
bcb894cb | 123 | int on = 1, fromlen; |
bb933cc2 | 124 | |
5d78ef73 GM |
125 | #if defined(DEBUG) |
126 | { | |
127 | int s, ns, foo; | |
128 | struct servent *sp; | |
129 | static struct sockaddr_in sin = { AF_INET }; | |
130 | ||
131 | sp = getservbyname("telnet", "tcp"); | |
132 | if (sp == 0) { | |
133 | fprintf(stderr, "telnetd: tcp/telnet: unknown service\n"); | |
134 | exit(1); | |
135 | } | |
136 | sin.sin_port = sp->s_port; | |
137 | argc--, argv++; | |
138 | if (argc > 0) { | |
139 | sin.sin_port = atoi(*argv); | |
140 | sin.sin_port = htons((u_short)sin.sin_port); | |
141 | } | |
142 | ||
143 | s = socket(AF_INET, SOCK_STREAM, 0); | |
144 | if (s < 0) { | |
145 | perror("telnetd: socket");; | |
146 | exit(1); | |
147 | } | |
148 | if (bind(s, &sin, sizeof sin) < 0) { | |
149 | perror("bind"); | |
150 | exit(1); | |
151 | } | |
152 | if (listen(s, 1) < 0) { | |
153 | perror("listen"); | |
154 | exit(1); | |
155 | } | |
156 | foo = sizeof sin; | |
157 | ns = accept(s, &sin, &foo); | |
158 | if (ns < 0) { | |
159 | perror("accept"); | |
160 | exit(1); | |
161 | } | |
162 | dup2(ns, 0); | |
163 | close(s); | |
164 | } | |
165 | #endif /* defined(DEBUG) */ | |
076ae92c | 166 | openlog("telnetd", LOG_PID | LOG_ODELAY, LOG_DAEMON); |
bb933cc2 MK |
167 | fromlen = sizeof (from); |
168 | if (getpeername(0, &from, &fromlen) < 0) { | |
169 | fprintf(stderr, "%s: ", argv[0]); | |
170 | perror("getpeername"); | |
171 | _exit(1); | |
de3b21e8 | 172 | } |
bcb894cb | 173 | if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof (on)) < 0) { |
3f99c0f7 | 174 | syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m"); |
de3b21e8 | 175 | } |
bb933cc2 | 176 | doit(0, &from); |
f553aca8 SL |
177 | } |
178 | ||
d8b5e42c GM |
179 | char *terminaltype = 0; |
180 | char *envinit[2]; | |
181 | int cleanup(); | |
affdaa4e GM |
182 | |
183 | /* | |
d8b5e42c | 184 | * ttloop |
affdaa4e | 185 | * |
d8b5e42c GM |
186 | * A small subroutine to flush the network output buffer, get some data |
187 | * from the network, and pass it through the telnet state machine. We | |
188 | * also flush the pty input buffer (by dropping its data) if it becomes | |
189 | * too full. | |
190 | */ | |
191 | ||
192 | void | |
193 | ttloop() | |
194 | { | |
195 | if (nfrontp-nbackp) { | |
196 | netflush(); | |
197 | } | |
198 | ncc = read(net, netibuf, sizeof netibuf); | |
199 | if (ncc < 0) { | |
200 | syslog(LOG_INFO, "ttloop: read: %m\n"); | |
10a3b37e GM |
201 | exit(1); |
202 | } else if (ncc == 0) { | |
203 | syslog(LOG_INFO, "ttloop: peer died: %m\n"); | |
204 | exit(1); | |
d8b5e42c GM |
205 | } |
206 | netip = netibuf; | |
207 | telrcv(); /* state machine */ | |
208 | if (ncc > 0) { | |
209 | pfrontp = pbackp = ptyobuf; | |
210 | telrcv(); | |
211 | } | |
212 | } | |
213 | ||
214 | /* | |
215 | * getterminaltype | |
affdaa4e | 216 | * |
d8b5e42c GM |
217 | * Ask the other end to send along its terminal type. |
218 | * Output is the variable terminaltype filled in. | |
affdaa4e GM |
219 | */ |
220 | ||
d8b5e42c GM |
221 | void |
222 | getterminaltype() | |
affdaa4e | 223 | { |
d8b5e42c | 224 | static char sbuf[] = { IAC, DO, TELOPT_TTYPE }; |
affdaa4e | 225 | |
d8b5e42c GM |
226 | settimer(getterminal); |
227 | bcopy(sbuf, nfrontp, sizeof sbuf); | |
228 | nfrontp += sizeof sbuf; | |
10a3b37e | 229 | hisopts[TELOPT_TTYPE] = OPT_YES_BUT_ALWAYS_LOOK; |
d8b5e42c GM |
230 | while (sequenceIs(ttypeopt, getterminal)) { |
231 | ttloop(); | |
affdaa4e | 232 | } |
d8b5e42c GM |
233 | if (hisopts[TELOPT_TTYPE] == OPT_YES) { |
234 | static char sbbuf[] = { IAC, SB, TELOPT_TTYPE, TELQUAL_SEND, IAC, SE }; | |
affdaa4e | 235 | |
d8b5e42c GM |
236 | bcopy(sbbuf, nfrontp, sizeof sbbuf); |
237 | nfrontp += sizeof sbbuf; | |
238 | while (sequenceIs(ttypesubopt, getterminal)) { | |
239 | ttloop(); | |
240 | } | |
241 | } | |
242 | } | |
66b878f6 BJ |
243 | |
244 | /* | |
245 | * Get a pty, scan input lines. | |
246 | */ | |
37c640e2 SL |
247 | doit(f, who) |
248 | int f; | |
249 | struct sockaddr_in *who; | |
66b878f6 | 250 | { |
c29f876c | 251 | char *host, *inet_ntoa(); |
1a33b848 | 252 | int i, p, t; |
66b878f6 | 253 | struct sgttyb b; |
37c640e2 | 254 | struct hostent *hp; |
affdaa4e | 255 | int c; |
1a33b848 | 256 | |
c29f876c MK |
257 | for (c = 'p'; c <= 's'; c++) { |
258 | struct stat stb; | |
259 | ||
260 | line = "/dev/ptyXX"; | |
261 | line[strlen("/dev/pty")] = c; | |
262 | line[strlen("/dev/ptyp")] = '0'; | |
263 | if (stat(line, &stb) < 0) | |
264 | break; | |
1a33b848 | 265 | for (i = 0; i < 16; i++) { |
312b6ead KB |
266 | line[sizeof("/dev/ptyp") - 1] = "0123456789abcdef"[i]; |
267 | p = open(line, O_RDWR); | |
1a33b848 SL |
268 | if (p > 0) |
269 | goto gotpty; | |
270 | } | |
66b878f6 | 271 | } |
8f2758db SL |
272 | fatal(f, "All network ports in use"); |
273 | /*NOTREACHED*/ | |
66b878f6 BJ |
274 | gotpty: |
275 | dup2(f, 0); | |
c29f876c | 276 | line[strlen("/dev/")] = 't'; |
1a33b848 | 277 | t = open("/dev/tty", O_RDWR); |
66b878f6 BJ |
278 | if (t >= 0) { |
279 | ioctl(t, TIOCNOTTY, 0); | |
280 | close(t); | |
281 | } | |
c29f876c | 282 | t = open(line, O_RDWR); |
8f2758db | 283 | if (t < 0) |
312b6ead KB |
284 | fatalperror(f, line); |
285 | if (fchmod(t, 0)) | |
286 | fatalperror(f, line); | |
287 | (void)signal(SIGHUP, SIG_IGN); | |
288 | vhangup(); | |
289 | (void)signal(SIGHUP, SIG_DFL); | |
290 | t = open(line, O_RDWR); | |
291 | if (t < 0) | |
292 | fatalperror(f, line); | |
66b878f6 | 293 | ioctl(t, TIOCGETP, &b); |
9ef3087d | 294 | b.sg_flags = CRMOD|XTABS|ANYP; |
66b878f6 | 295 | ioctl(t, TIOCSETP, &b); |
9ef3087d | 296 | ioctl(p, TIOCGETP, &b); |
da96b661 | 297 | b.sg_flags &= ~ECHO; |
9ef3087d | 298 | ioctl(p, TIOCSETP, &b); |
37c640e2 SL |
299 | hp = gethostbyaddr(&who->sin_addr, sizeof (struct in_addr), |
300 | who->sin_family); | |
301 | if (hp) | |
302 | host = hp->h_name; | |
303 | else | |
05fa5465 | 304 | host = inet_ntoa(who->sin_addr); |
d8b5e42c GM |
305 | |
306 | net = f; | |
307 | pty = p; | |
308 | ||
309 | /* | |
310 | * get terminal type. | |
311 | */ | |
312 | getterminaltype(); | |
313 | ||
8f2758db | 314 | if ((i = fork()) < 0) |
312b6ead | 315 | fatalperror(f, "fork"); |
66b878f6 BJ |
316 | if (i) |
317 | telnet(f, p); | |
318 | close(f); | |
319 | close(p); | |
320 | dup2(t, 0); | |
321 | dup2(t, 1); | |
322 | dup2(t, 2); | |
323 | close(t); | |
d8b5e42c GM |
324 | envinit[0] = terminaltype; |
325 | envinit[1] = 0; | |
fe5c5547 | 326 | environ = envinit; |
affdaa4e GM |
327 | /* |
328 | * -h : pass on name of host. | |
d8b5e42c GM |
329 | * WARNING: -h is accepted by login if and only if |
330 | * getuid() == 0. | |
affdaa4e GM |
331 | * -p : don't clobber the environment (so terminal type stays set). |
332 | */ | |
333 | execl("/bin/login", "login", "-h", host, | |
d8b5e42c | 334 | terminaltype ? "-p" : 0, 0); |
312b6ead | 335 | fatalperror(f, "/bin/login"); |
8f2758db SL |
336 | /*NOTREACHED*/ |
337 | } | |
338 | ||
339 | fatal(f, msg) | |
340 | int f; | |
341 | char *msg; | |
342 | { | |
343 | char buf[BUFSIZ]; | |
344 | ||
1a33b848 | 345 | (void) sprintf(buf, "telnetd: %s.\r\n", msg); |
8f2758db | 346 | (void) write(f, buf, strlen(buf)); |
66b878f6 BJ |
347 | exit(1); |
348 | } | |
349 | ||
312b6ead | 350 | fatalperror(f, msg) |
8f2758db SL |
351 | int f; |
352 | char *msg; | |
8f2758db SL |
353 | { |
354 | char buf[BUFSIZ]; | |
355 | extern char *sys_errlist[]; | |
356 | ||
1a33b848 | 357 | (void) sprintf(buf, "%s: %s\r\n", msg, sys_errlist[errno]); |
8f2758db SL |
358 | fatal(f, buf); |
359 | } | |
360 | ||
5d78ef73 GM |
361 | |
362 | /* | |
363 | * Check a descriptor to see if out of band data exists on it. | |
364 | */ | |
365 | ||
366 | ||
367 | stilloob(s) | |
368 | int s; /* socket number */ | |
369 | { | |
370 | static struct timeval timeout = { 0 }; | |
371 | fd_set excepts; | |
372 | int value; | |
373 | ||
374 | do { | |
375 | FD_ZERO(&excepts); | |
376 | FD_SET(s, &excepts); | |
377 | value = select(s+1, (fd_set *)0, (fd_set *)0, &excepts, &timeout); | |
5eddff6d | 378 | } while ((value == -1) && (errno == EINTR)); |
5d78ef73 GM |
379 | |
380 | if (value < 0) { | |
312b6ead | 381 | fatalperror(pty, "select"); |
5d78ef73 GM |
382 | } |
383 | if (FD_ISSET(s, &excepts)) { | |
384 | return 1; | |
385 | } else { | |
386 | return 0; | |
387 | } | |
388 | } | |
389 | \f | |
66b878f6 BJ |
390 | /* |
391 | * Main loop. Select from pty and network, and | |
392 | * hand data to telnet receiver finite state machine. | |
393 | */ | |
394 | telnet(f, p) | |
395 | { | |
396 | int on = 1; | |
5eddff6d | 397 | char hostname[MAXHOSTNAMELEN]; |
d0a64c71 GM |
398 | #define TABBUFSIZ 512 |
399 | char defent[TABBUFSIZ]; | |
400 | char defstrs[TABBUFSIZ]; | |
401 | #undef TABBUFSIZ | |
402 | char *HE; | |
403 | char *HN; | |
404 | char *IM; | |
66b878f6 | 405 | |
66b878f6 BJ |
406 | ioctl(f, FIONBIO, &on); |
407 | ioctl(p, FIONBIO, &on); | |
4701a1c1 | 408 | ioctl(p, TIOCPKT, &on); |
affdaa4e GM |
409 | #if defined(SO_OOBINLINE) |
410 | setsockopt(net, SOL_SOCKET, SO_OOBINLINE, &on, sizeof on); | |
411 | #endif /* defined(SO_OOBINLINE) */ | |
66b878f6 | 412 | signal(SIGTSTP, SIG_IGN); |
9eebc521 GM |
413 | /* |
414 | * Ignoring SIGTTOU keeps the kernel from blocking us | |
415 | * in ttioctl() in /sys/tty.c. | |
416 | */ | |
417 | signal(SIGTTOU, SIG_IGN); | |
8a53982e | 418 | signal(SIGCHLD, cleanup); |
f4c5d9f9 | 419 | setpgrp(0, 0); |
66b878f6 | 420 | |
da96b661 | 421 | /* |
5d78ef73 | 422 | * Request to do remote echo and to suppress go ahead. |
da96b661 | 423 | */ |
d8b5e42c GM |
424 | if (!myopts[TELOPT_ECHO]) { |
425 | dooption(TELOPT_ECHO); | |
426 | } | |
427 | if (!myopts[TELOPT_SGA]) { | |
428 | dooption(TELOPT_SGA); | |
429 | } | |
affdaa4e GM |
430 | /* |
431 | * Is the client side a 4.2 (NOT 4.3) system? We need to know this | |
432 | * because 4.2 clients are unable to deal with TCP urgent data. | |
433 | * | |
434 | * To find out, we send out a "DO ECHO". If the remote system | |
435 | * answers "WILL ECHO" it is probably a 4.2 client, and we note | |
436 | * that fact ("WILL ECHO" ==> that the client will echo what | |
437 | * WE, the server, sends it; it does NOT mean that the client will | |
438 | * echo the terminal input). | |
439 | */ | |
9bd38ba8 | 440 | (void) sprintf(nfrontp, doopt, TELOPT_ECHO); |
affdaa4e | 441 | nfrontp += sizeof doopt-2; |
d8b5e42c | 442 | hisopts[TELOPT_ECHO] = OPT_YES_BUT_ALWAYS_LOOK; |
affdaa4e | 443 | |
0c285f22 SL |
444 | /* |
445 | * Show banner that getty never gave. | |
10dc182f | 446 | * |
d0a64c71 GM |
447 | * We put the banner in the pty input buffer. This way, it |
448 | * gets carriage return null processing, etc., just like all | |
449 | * other pty --> client data. | |
0c285f22 | 450 | */ |
10dc182f | 451 | |
0c285f22 | 452 | gethostname(hostname, sizeof (hostname)); |
d0a64c71 GM |
453 | if (getent(defent, "default") == 1) { |
454 | char *getstr(); | |
455 | char *p=defstrs; | |
456 | ||
457 | HE = getstr("he", &p); | |
458 | HN = getstr("hn", &p); | |
459 | IM = getstr("im", &p); | |
460 | if (HN && *HN) | |
461 | strcpy(hostname, HN); | |
462 | edithost(HE, hostname); | |
463 | if (IM && *IM) | |
312b6ead | 464 | putf(IM, ptyibuf+1); |
d0a64c71 GM |
465 | } else { |
466 | sprintf(ptyibuf+1, BANNER, hostname); | |
467 | } | |
10dc182f | 468 | |
d0a64c71 GM |
469 | ptyip = ptyibuf+1; /* Prime the pump */ |
470 | pcc = strlen(ptyip); /* ditto */ | |
affdaa4e | 471 | |
4701a1c1 GM |
472 | /* Clear ptybuf[0] - where the packet information is received */ |
473 | ptyibuf[0] = 0; | |
d0a64c71 | 474 | |
affdaa4e GM |
475 | /* |
476 | * Call telrcv() once to pick up anything received during | |
477 | * terminal type negotiation. | |
478 | */ | |
479 | telrcv(); | |
480 | ||
66b878f6 | 481 | for (;;) { |
5d78ef73 | 482 | fd_set ibits, obits, xbits; |
66b878f6 BJ |
483 | register int c; |
484 | ||
5d78ef73 GM |
485 | if (ncc < 0 && pcc < 0) |
486 | break; | |
487 | ||
488 | FD_ZERO(&ibits); | |
489 | FD_ZERO(&obits); | |
490 | FD_ZERO(&xbits); | |
66b878f6 BJ |
491 | /* |
492 | * Never look for input if there's still | |
493 | * stuff in the corresponding output buffer | |
494 | */ | |
5d78ef73 GM |
495 | if (nfrontp - nbackp || pcc > 0) { |
496 | FD_SET(f, &obits); | |
4701a1c1 | 497 | FD_SET(p, &xbits); |
5d78ef73 GM |
498 | } else { |
499 | FD_SET(p, &ibits); | |
500 | } | |
501 | if (pfrontp - pbackp || ncc > 0) { | |
502 | FD_SET(p, &obits); | |
503 | } else { | |
504 | FD_SET(f, &ibits); | |
505 | } | |
506 | if (!SYNCHing) { | |
507 | FD_SET(f, &xbits); | |
508 | } | |
509 | if ((c = select(16, &ibits, &obits, &xbits, | |
510 | (struct timeval *)0)) < 1) { | |
511 | if (c == -1) { | |
512 | if (errno == EINTR) { | |
513 | continue; | |
514 | } | |
515 | } | |
66b878f6 BJ |
516 | sleep(5); |
517 | continue; | |
518 | } | |
519 | ||
5d78ef73 GM |
520 | /* |
521 | * Any urgent data? | |
522 | */ | |
523 | if (FD_ISSET(net, &xbits)) { | |
524 | SYNCHing = 1; | |
525 | } | |
526 | ||
66b878f6 BJ |
527 | /* |
528 | * Something to read from the network... | |
529 | */ | |
5d78ef73 | 530 | if (FD_ISSET(net, &ibits)) { |
affdaa4e | 531 | #if !defined(SO_OOBINLINE) |
5d78ef73 | 532 | /* |
5eddff6d | 533 | * In 4.2 (and 4.3 beta) systems, the |
5d78ef73 GM |
534 | * OOB indication and data handling in the kernel |
535 | * is such that if two separate TCP Urgent requests | |
536 | * come in, one byte of TCP data will be overlaid. | |
537 | * This is fatal for Telnet, but we try to live | |
538 | * with it. | |
539 | * | |
540 | * In addition, in 4.2 (and...), a special protocol | |
541 | * is needed to pick up the TCP Urgent data in | |
542 | * the correct sequence. | |
543 | * | |
544 | * What we do is: if we think we are in urgent | |
545 | * mode, we look to see if we are "at the mark". | |
546 | * If we are, we do an OOB receive. If we run | |
547 | * this twice, we will do the OOB receive twice, | |
548 | * but the second will fail, since the second | |
549 | * time we were "at the mark", but there wasn't | |
550 | * any data there (the kernel doesn't reset | |
551 | * "at the mark" until we do a normal read). | |
552 | * Once we've read the OOB data, we go ahead | |
553 | * and do normal reads. | |
554 | * | |
555 | * There is also another problem, which is that | |
556 | * since the OOB byte we read doesn't put us | |
557 | * out of OOB state, and since that byte is most | |
558 | * likely the TELNET DM (data mark), we would | |
559 | * stay in the TELNET SYNCH (SYNCHing) state. | |
560 | * So, clocks to the rescue. If we've "just" | |
561 | * received a DM, then we test for the | |
562 | * presence of OOB data when the receive OOB | |
563 | * fails (and AFTER we did the normal mode read | |
564 | * to clear "at the mark"). | |
565 | */ | |
566 | if (SYNCHing) { | |
567 | int atmark; | |
568 | ||
569 | ioctl(net, SIOCATMARK, (char *)&atmark); | |
570 | if (atmark) { | |
571 | ncc = recv(net, netibuf, sizeof (netibuf), MSG_OOB); | |
572 | if ((ncc == -1) && (errno == EINVAL)) { | |
573 | ncc = read(net, netibuf, sizeof (netibuf)); | |
d8b5e42c | 574 | if (sequenceIs(didnetreceive, gotDM)) { |
5d78ef73 GM |
575 | SYNCHing = stilloob(net); |
576 | } | |
577 | } | |
578 | } else { | |
579 | ncc = read(net, netibuf, sizeof (netibuf)); | |
66b878f6 | 580 | } |
5d78ef73 GM |
581 | } else { |
582 | ncc = read(net, netibuf, sizeof (netibuf)); | |
583 | } | |
584 | settimer(didnetreceive); | |
affdaa4e | 585 | #else /* !defined(SO_OOBINLINE)) */ |
5d78ef73 | 586 | ncc = read(net, netibuf, sizeof (netibuf)); |
affdaa4e | 587 | #endif /* !defined(SO_OOBINLINE)) */ |
5d78ef73 GM |
588 | if (ncc < 0 && errno == EWOULDBLOCK) |
589 | ncc = 0; | |
590 | else { | |
591 | if (ncc <= 0) { | |
592 | break; | |
593 | } | |
594 | netip = netibuf; | |
595 | } | |
66b878f6 BJ |
596 | } |
597 | ||
598 | /* | |
599 | * Something to read from the pty... | |
600 | */ | |
4701a1c1 GM |
601 | if (FD_ISSET(p, &xbits)) { |
602 | if (read(p, ptyibuf, 1) != 1) { | |
603 | break; | |
604 | } | |
605 | } | |
5d78ef73 | 606 | if (FD_ISSET(p, &ibits)) { |
66b878f6 BJ |
607 | pcc = read(p, ptyibuf, BUFSIZ); |
608 | if (pcc < 0 && errno == EWOULDBLOCK) | |
609 | pcc = 0; | |
610 | else { | |
611 | if (pcc <= 0) | |
612 | break; | |
4701a1c1 GM |
613 | /* Skip past "packet" */ |
614 | pcc--; | |
615 | ptyip = ptyibuf+1; | |
66b878f6 BJ |
616 | } |
617 | } | |
4701a1c1 GM |
618 | if (ptyibuf[0] & TIOCPKT_FLUSHWRITE) { |
619 | netclear(); /* clear buffer back */ | |
620 | *nfrontp++ = IAC; | |
621 | *nfrontp++ = DM; | |
622 | neturg = nfrontp-1; /* off by one XXX */ | |
623 | ptyibuf[0] = 0; | |
624 | } | |
66b878f6 BJ |
625 | |
626 | while (pcc > 0) { | |
627 | if ((&netobuf[BUFSIZ] - nfrontp) < 2) | |
628 | break; | |
629 | c = *ptyip++ & 0377, pcc--; | |
630 | if (c == IAC) | |
631 | *nfrontp++ = c; | |
632 | *nfrontp++ = c; | |
bdb993e7 KB |
633 | /* Don't do CR-NUL if we are in binary mode */ |
634 | if ((c == '\r') && (myopts[TELOPT_BINARY] == OPT_NO)) { | |
9f515693 GM |
635 | if (pcc > 0 && ((*ptyip & 0377) == '\n')) { |
636 | *nfrontp++ = *ptyip++ & 0377; | |
637 | pcc--; | |
638 | } else | |
639 | *nfrontp++ = '\0'; | |
640 | } | |
66b878f6 | 641 | } |
5d78ef73 | 642 | if (FD_ISSET(f, &obits) && (nfrontp - nbackp) > 0) |
66b878f6 BJ |
643 | netflush(); |
644 | if (ncc > 0) | |
645 | telrcv(); | |
5d78ef73 | 646 | if (FD_ISSET(p, &obits) && (pfrontp - pbackp) > 0) |
66b878f6 BJ |
647 | ptyflush(); |
648 | } | |
649 | cleanup(); | |
650 | } | |
651 | ||
652 | /* | |
653 | * State for recv fsm | |
654 | */ | |
655 | #define TS_DATA 0 /* base state */ | |
656 | #define TS_IAC 1 /* look for double IAC's */ | |
657 | #define TS_CR 2 /* CR-LF ->'s CR */ | |
affdaa4e GM |
658 | #define TS_SB 3 /* throw away begin's... */ |
659 | #define TS_SE 4 /* ...end's (suboption negotiation) */ | |
66b878f6 BJ |
660 | #define TS_WILL 5 /* will option negotiation */ |
661 | #define TS_WONT 6 /* wont " */ | |
662 | #define TS_DO 7 /* do " */ | |
663 | #define TS_DONT 8 /* dont " */ | |
664 | ||
665 | telrcv() | |
666 | { | |
667 | register int c; | |
668 | static int state = TS_DATA; | |
66b878f6 BJ |
669 | |
670 | while (ncc > 0) { | |
671 | if ((&ptyobuf[BUFSIZ] - pfrontp) < 2) | |
672 | return; | |
673 | c = *netip++ & 0377, ncc--; | |
674 | switch (state) { | |
675 | ||
8356bfad GM |
676 | case TS_CR: |
677 | state = TS_DATA; | |
07f70d31 | 678 | /* Strip off \n or \0 after a \r */ |
a6d8450f | 679 | if ((c == 0) || (c == '\n')) { |
8356bfad | 680 | break; |
a6d8450f | 681 | } |
8356bfad GM |
682 | /* FALL THROUGH */ |
683 | ||
66b878f6 BJ |
684 | case TS_DATA: |
685 | if (c == IAC) { | |
686 | state = TS_IAC; | |
687 | break; | |
688 | } | |
689 | if (inter > 0) | |
690 | break; | |
9f515693 | 691 | /* |
07f70d31 GM |
692 | * We now map \r\n ==> \r for pragmatic reasons. |
693 | * Many client implementations send \r\n when | |
694 | * the user hits the CarriageReturn key. | |
695 | * | |
696 | * We USED to map \r\n ==> \n, since \r\n says | |
9f515693 GM |
697 | * that we want to be in column 1 of the next |
698 | * printable line, and \n is the standard | |
699 | * unix way of saying that (\r is only good | |
700 | * if CRMOD is set, which it normally is). | |
701 | */ | |
bdb993e7 | 702 | if ((c == '\r') && (hisopts[TELOPT_BINARY] == OPT_NO)) { |
07f70d31 | 703 | state = TS_CR; |
a6d8450f GM |
704 | } |
705 | *pfrontp++ = c; | |
66b878f6 BJ |
706 | break; |
707 | ||
708 | case TS_IAC: | |
709 | switch (c) { | |
710 | ||
711 | /* | |
712 | * Send the process on the pty side an | |
713 | * interrupt. Do this with a NULL or | |
714 | * interrupt char; depending on the tty mode. | |
715 | */ | |
66b878f6 BJ |
716 | case IP: |
717 | interrupt(); | |
718 | break; | |
719 | ||
a65453b7 GM |
720 | case BREAK: |
721 | sendbrk(); | |
722 | break; | |
723 | ||
66b878f6 BJ |
724 | /* |
725 | * Are You There? | |
726 | */ | |
727 | case AYT: | |
1a33b848 SL |
728 | strcpy(nfrontp, "\r\n[Yes]\r\n"); |
729 | nfrontp += 9; | |
66b878f6 BJ |
730 | break; |
731 | ||
5d78ef73 GM |
732 | /* |
733 | * Abort Output | |
734 | */ | |
735 | case AO: { | |
736 | struct ltchars tmpltc; | |
737 | ||
738 | ptyflush(); /* half-hearted */ | |
739 | ioctl(pty, TIOCGLTC, &tmpltc); | |
740 | if (tmpltc.t_flushc != '\377') { | |
741 | *pfrontp++ = tmpltc.t_flushc; | |
742 | } | |
615dc3cd | 743 | netclear(); /* clear buffer back */ |
5d78ef73 GM |
744 | *nfrontp++ = IAC; |
745 | *nfrontp++ = DM; | |
c77c3bec | 746 | neturg = nfrontp-1; /* off by one XXX */ |
5d78ef73 GM |
747 | break; |
748 | } | |
749 | ||
66b878f6 BJ |
750 | /* |
751 | * Erase Character and | |
752 | * Erase Line | |
753 | */ | |
754 | case EC: | |
5d78ef73 GM |
755 | case EL: { |
756 | struct sgttyb b; | |
757 | char ch; | |
758 | ||
759 | ptyflush(); /* half-hearted */ | |
760 | ioctl(pty, TIOCGETP, &b); | |
761 | ch = (c == EC) ? | |
762 | b.sg_erase : b.sg_kill; | |
763 | if (ch != '\377') { | |
764 | *pfrontp++ = ch; | |
765 | } | |
766 | break; | |
767 | } | |
66b878f6 BJ |
768 | |
769 | /* | |
770 | * Check for urgent data... | |
771 | */ | |
772 | case DM: | |
5d78ef73 GM |
773 | SYNCHing = stilloob(net); |
774 | settimer(gotDM); | |
66b878f6 BJ |
775 | break; |
776 | ||
5d78ef73 | 777 | |
66b878f6 BJ |
778 | /* |
779 | * Begin option subnegotiation... | |
780 | */ | |
781 | case SB: | |
affdaa4e | 782 | state = TS_SB; |
66b878f6 BJ |
783 | continue; |
784 | ||
785 | case WILL: | |
0e376915 GM |
786 | state = TS_WILL; |
787 | continue; | |
788 | ||
66b878f6 | 789 | case WONT: |
0e376915 GM |
790 | state = TS_WONT; |
791 | continue; | |
792 | ||
66b878f6 | 793 | case DO: |
0e376915 GM |
794 | state = TS_DO; |
795 | continue; | |
796 | ||
66b878f6 | 797 | case DONT: |
0e376915 | 798 | state = TS_DONT; |
66b878f6 BJ |
799 | continue; |
800 | ||
801 | case IAC: | |
802 | *pfrontp++ = c; | |
803 | break; | |
804 | } | |
805 | state = TS_DATA; | |
806 | break; | |
807 | ||
affdaa4e GM |
808 | case TS_SB: |
809 | if (c == IAC) { | |
810 | state = TS_SE; | |
811 | } else { | |
812 | SB_ACCUM(c); | |
813 | } | |
66b878f6 BJ |
814 | break; |
815 | ||
affdaa4e GM |
816 | case TS_SE: |
817 | if (c != SE) { | |
818 | if (c != IAC) { | |
819 | SB_ACCUM(IAC); | |
820 | } | |
821 | SB_ACCUM(c); | |
822 | state = TS_SB; | |
823 | } else { | |
824 | SB_TERM(); | |
825 | suboption(); /* handle sub-option */ | |
826 | state = TS_DATA; | |
827 | } | |
66b878f6 BJ |
828 | break; |
829 | ||
830 | case TS_WILL: | |
d8b5e42c | 831 | if (hisopts[c] != OPT_YES) |
66b878f6 BJ |
832 | willoption(c); |
833 | state = TS_DATA; | |
834 | continue; | |
835 | ||
836 | case TS_WONT: | |
d8b5e42c | 837 | if (hisopts[c] != OPT_NO) |
66b878f6 BJ |
838 | wontoption(c); |
839 | state = TS_DATA; | |
840 | continue; | |
841 | ||
842 | case TS_DO: | |
d8b5e42c | 843 | if (myopts[c] != OPT_YES) |
66b878f6 BJ |
844 | dooption(c); |
845 | state = TS_DATA; | |
846 | continue; | |
847 | ||
848 | case TS_DONT: | |
d8b5e42c | 849 | if (myopts[c] != OPT_NO) { |
affdaa4e | 850 | dontoption(c); |
66b878f6 BJ |
851 | } |
852 | state = TS_DATA; | |
853 | continue; | |
854 | ||
855 | default: | |
5eddff6d | 856 | syslog(LOG_ERR, "telnetd: panic state=%d\n", state); |
de3b21e8 | 857 | printf("telnetd: panic state=%d\n", state); |
66b878f6 BJ |
858 | exit(1); |
859 | } | |
860 | } | |
861 | } | |
862 | ||
863 | willoption(option) | |
864 | int option; | |
865 | { | |
866 | char *fmt; | |
867 | ||
868 | switch (option) { | |
869 | ||
870 | case TELOPT_BINARY: | |
871 | mode(RAW, 0); | |
0e376915 GM |
872 | fmt = doopt; |
873 | break; | |
66b878f6 BJ |
874 | |
875 | case TELOPT_ECHO: | |
affdaa4e GM |
876 | not42 = 0; /* looks like a 4.2 system */ |
877 | /* | |
878 | * Now, in a 4.2 system, to break them out of ECHOing | |
879 | * (to the terminal) mode, we need to send a "WILL ECHO". | |
880 | * Kludge upon kludge! | |
881 | */ | |
d8b5e42c | 882 | if (myopts[TELOPT_ECHO] == OPT_YES) { |
affdaa4e GM |
883 | dooption(TELOPT_ECHO); |
884 | } | |
885 | fmt = dont; | |
0e376915 | 886 | break; |
66b878f6 | 887 | |
affdaa4e | 888 | case TELOPT_TTYPE: |
d8b5e42c GM |
889 | settimer(ttypeopt); |
890 | if (hisopts[TELOPT_TTYPE] == OPT_YES_BUT_ALWAYS_LOOK) { | |
891 | hisopts[TELOPT_TTYPE] = OPT_YES; | |
892 | return; | |
893 | } | |
894 | fmt = doopt; | |
895 | break; | |
896 | ||
66b878f6 | 897 | case TELOPT_SGA: |
66b878f6 BJ |
898 | fmt = doopt; |
899 | break; | |
900 | ||
901 | case TELOPT_TM: | |
902 | fmt = dont; | |
903 | break; | |
904 | ||
905 | default: | |
906 | fmt = dont; | |
907 | break; | |
908 | } | |
0e376915 | 909 | if (fmt == doopt) { |
d8b5e42c | 910 | hisopts[option] = OPT_YES; |
0e376915 | 911 | } else { |
d8b5e42c | 912 | hisopts[option] = OPT_NO; |
0e376915 | 913 | } |
9bd38ba8 | 914 | (void) sprintf(nfrontp, fmt, option); |
da96b661 | 915 | nfrontp += sizeof (dont) - 2; |
66b878f6 BJ |
916 | } |
917 | ||
918 | wontoption(option) | |
919 | int option; | |
920 | { | |
921 | char *fmt; | |
922 | ||
923 | switch (option) { | |
66b878f6 | 924 | case TELOPT_ECHO: |
affdaa4e | 925 | not42 = 1; /* doesn't seem to be a 4.2 system */ |
0e376915 | 926 | break; |
66b878f6 BJ |
927 | |
928 | case TELOPT_BINARY: | |
929 | mode(0, RAW); | |
66b878f6 | 930 | break; |
10a3b37e GM |
931 | |
932 | case TELOPT_TTYPE: | |
933 | settimer(ttypeopt); | |
934 | break; | |
66b878f6 | 935 | } |
10a3b37e | 936 | |
0e376915 | 937 | fmt = dont; |
d8b5e42c | 938 | hisopts[option] = OPT_NO; |
9bd38ba8 | 939 | (void) sprintf(nfrontp, fmt, option); |
da96b661 | 940 | nfrontp += sizeof (doopt) - 2; |
66b878f6 BJ |
941 | } |
942 | ||
943 | dooption(option) | |
944 | int option; | |
945 | { | |
946 | char *fmt; | |
947 | ||
948 | switch (option) { | |
949 | ||
950 | case TELOPT_TM: | |
951 | fmt = wont; | |
952 | break; | |
953 | ||
954 | case TELOPT_ECHO: | |
955 | mode(ECHO|CRMOD, 0); | |
0e376915 GM |
956 | fmt = will; |
957 | break; | |
66b878f6 BJ |
958 | |
959 | case TELOPT_BINARY: | |
960 | mode(RAW, 0); | |
0e376915 GM |
961 | fmt = will; |
962 | break; | |
66b878f6 BJ |
963 | |
964 | case TELOPT_SGA: | |
66b878f6 BJ |
965 | fmt = will; |
966 | break; | |
967 | ||
968 | default: | |
969 | fmt = wont; | |
970 | break; | |
971 | } | |
0e376915 | 972 | if (fmt == will) { |
d8b5e42c | 973 | myopts[option] = OPT_YES; |
0e376915 | 974 | } else { |
d8b5e42c | 975 | myopts[option] = OPT_NO; |
0e376915 | 976 | } |
9bd38ba8 | 977 | (void) sprintf(nfrontp, fmt, option); |
da96b661 | 978 | nfrontp += sizeof (doopt) - 2; |
66b878f6 BJ |
979 | } |
980 | ||
affdaa4e GM |
981 | |
982 | dontoption(option) | |
983 | int option; | |
984 | { | |
985 | char *fmt; | |
986 | ||
987 | switch (option) { | |
988 | case TELOPT_ECHO: /* we should stop echoing */ | |
38260ba2 | 989 | mode(0, ECHO); |
affdaa4e GM |
990 | fmt = wont; |
991 | break; | |
d8b5e42c | 992 | |
affdaa4e GM |
993 | default: |
994 | fmt = wont; | |
995 | break; | |
996 | } | |
d8b5e42c | 997 | |
affdaa4e | 998 | if (fmt = wont) { |
d8b5e42c | 999 | myopts[option] = OPT_NO; |
affdaa4e | 1000 | } else { |
d8b5e42c | 1001 | myopts[option] = OPT_YES; |
affdaa4e | 1002 | } |
9bd38ba8 | 1003 | (void) sprintf(nfrontp, fmt, option); |
affdaa4e GM |
1004 | nfrontp += sizeof (wont) - 2; |
1005 | } | |
1006 | ||
1007 | /* | |
1008 | * suboption() | |
1009 | * | |
1010 | * Look at the sub-option buffer, and try to be helpful to the other | |
1011 | * side. | |
1012 | * | |
1013 | * Currently we recognize: | |
1014 | * | |
d8b5e42c | 1015 | * Terminal type is |
affdaa4e GM |
1016 | */ |
1017 | ||
1018 | suboption() | |
1019 | { | |
d8b5e42c GM |
1020 | switch (SB_GET()) { |
1021 | case TELOPT_TTYPE: { /* Yaaaay! */ | |
1022 | static char terminalname[5+41] = "TERM="; | |
1023 | ||
1024 | settimer(ttypesubopt); | |
1025 | ||
1026 | if (SB_GET() != TELQUAL_IS) { | |
1027 | return; /* ??? XXX but, this is the most robust */ | |
1028 | } | |
1029 | ||
1030 | terminaltype = terminalname+strlen(terminalname); | |
1031 | ||
1032 | while ((terminaltype < (terminalname + sizeof terminalname-1)) && | |
1033 | !SB_EOF()) { | |
1034 | register int c; | |
1035 | ||
1036 | c = SB_GET(); | |
1037 | if (isupper(c)) { | |
1038 | c = tolower(c); | |
1039 | } | |
1040 | *terminaltype++ = c; /* accumulate name */ | |
1041 | } | |
1042 | *terminaltype = 0; | |
1043 | terminaltype = terminalname; | |
1044 | break; | |
1045 | } | |
1046 | ||
affdaa4e GM |
1047 | default: |
1048 | ; | |
1049 | } | |
1050 | } | |
1051 | ||
66b878f6 BJ |
1052 | mode(on, off) |
1053 | int on, off; | |
1054 | { | |
1055 | struct sgttyb b; | |
1056 | ||
1057 | ptyflush(); | |
1058 | ioctl(pty, TIOCGETP, &b); | |
1059 | b.sg_flags |= on; | |
1060 | b.sg_flags &= ~off; | |
1061 | ioctl(pty, TIOCSETP, &b); | |
1062 | } | |
1063 | ||
1064 | /* | |
1065 | * Send interrupt to process on other side of pty. | |
1066 | * If it is in raw mode, just write NULL; | |
1067 | * otherwise, write intr char. | |
1068 | */ | |
1069 | interrupt() | |
1070 | { | |
1071 | struct sgttyb b; | |
1072 | struct tchars tchars; | |
1073 | ||
1074 | ptyflush(); /* half-hearted */ | |
1075 | ioctl(pty, TIOCGETP, &b); | |
1076 | if (b.sg_flags & RAW) { | |
1077 | *pfrontp++ = '\0'; | |
1078 | return; | |
1079 | } | |
1080 | *pfrontp++ = ioctl(pty, TIOCGETC, &tchars) < 0 ? | |
1081 | '\177' : tchars.t_intrc; | |
1082 | } | |
1083 | ||
a65453b7 GM |
1084 | /* |
1085 | * Send quit to process on other side of pty. | |
1086 | * If it is in raw mode, just write NULL; | |
1087 | * otherwise, write quit char. | |
1088 | */ | |
1089 | sendbrk() | |
1090 | { | |
1091 | struct sgttyb b; | |
1092 | struct tchars tchars; | |
1093 | ||
1094 | ptyflush(); /* half-hearted */ | |
1095 | ioctl(pty, TIOCGETP, &b); | |
1096 | if (b.sg_flags & RAW) { | |
1097 | *pfrontp++ = '\0'; | |
1098 | return; | |
1099 | } | |
1100 | *pfrontp++ = ioctl(pty, TIOCGETC, &tchars) < 0 ? | |
1101 | '\034' : tchars.t_quitc; | |
1102 | } | |
1103 | ||
66b878f6 BJ |
1104 | ptyflush() |
1105 | { | |
1106 | int n; | |
1107 | ||
1108 | if ((n = pfrontp - pbackp) > 0) | |
1109 | n = write(pty, pbackp, n); | |
9f005877 SL |
1110 | if (n < 0) |
1111 | return; | |
66b878f6 BJ |
1112 | pbackp += n; |
1113 | if (pbackp == pfrontp) | |
1114 | pbackp = pfrontp = ptyobuf; | |
1115 | } | |
615dc3cd GM |
1116 | \f |
1117 | /* | |
1118 | * nextitem() | |
1119 | * | |
1120 | * Return the address of the next "item" in the TELNET data | |
1121 | * stream. This will be the address of the next character if | |
1122 | * the current address is a user data character, or it will | |
1123 | * be the address of the character following the TELNET command | |
1124 | * if the current address is a TELNET IAC ("I Am a Command") | |
1125 | * character. | |
1126 | */ | |
66b878f6 | 1127 | |
615dc3cd GM |
1128 | char * |
1129 | nextitem(current) | |
1130 | char *current; | |
66b878f6 | 1131 | { |
615dc3cd GM |
1132 | if ((*current&0xff) != IAC) { |
1133 | return current+1; | |
1134 | } | |
1135 | switch (*(current+1)&0xff) { | |
1136 | case DO: | |
1137 | case DONT: | |
1138 | case WILL: | |
1139 | case WONT: | |
1140 | return current+3; | |
1141 | case SB: /* loop forever looking for the SE */ | |
1142 | { | |
1143 | register char *look = current+2; | |
66b878f6 | 1144 | |
615dc3cd GM |
1145 | for (;;) { |
1146 | if ((*look++&0xff) == IAC) { | |
1147 | if ((*look++&0xff) == SE) { | |
1148 | return look; | |
1149 | } | |
1150 | } | |
1151 | } | |
9f005877 | 1152 | } |
615dc3cd GM |
1153 | default: |
1154 | return current+2; | |
1155 | } | |
66b878f6 | 1156 | } |
5d78ef73 GM |
1157 | |
1158 | ||
615dc3cd GM |
1159 | /* |
1160 | * netclear() | |
1161 | * | |
1162 | * We are about to do a TELNET SYNCH operation. Clear | |
1163 | * the path to the network. | |
1164 | * | |
1165 | * Things are a bit tricky since we may have sent the first | |
1166 | * byte or so of a previous TELNET command into the network. | |
1167 | * So, we have to scan the network buffer from the beginning | |
1168 | * until we are up to where we want to be. | |
1169 | * | |
1170 | * A side effect of what we do, just to keep things | |
1171 | * simple, is to clear the urgent data pointer. The principal | |
1172 | * caller should be setting the urgent data pointer AFTER calling | |
1173 | * us in any case. | |
1174 | */ | |
1175 | ||
1176 | netclear() | |
1177 | { | |
1178 | register char *thisitem, *next; | |
1179 | char *good; | |
1180 | #define wewant(p) ((nfrontp > p) && ((*p&0xff) == IAC) && \ | |
1181 | ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL)) | |
1182 | ||
1183 | thisitem = netobuf; | |
1184 | ||
1185 | while ((next = nextitem(thisitem)) <= nbackp) { | |
1186 | thisitem = next; | |
1187 | } | |
1188 | ||
1189 | /* Now, thisitem is first before/at boundary. */ | |
1190 | ||
1191 | good = netobuf; /* where the good bytes go */ | |
1192 | ||
1193 | while (nfrontp > thisitem) { | |
1194 | if (wewant(thisitem)) { | |
1195 | int length; | |
1196 | ||
1197 | next = thisitem; | |
1198 | do { | |
1199 | next = nextitem(next); | |
1200 | } while (wewant(next) && (nfrontp > next)); | |
1201 | length = next-thisitem; | |
1202 | bcopy(thisitem, good, length); | |
1203 | good += length; | |
1204 | thisitem = next; | |
1205 | } else { | |
1206 | thisitem = nextitem(thisitem); | |
1207 | } | |
1208 | } | |
1209 | ||
1210 | nbackp = netobuf; | |
1211 | nfrontp = good; /* next byte to be sent */ | |
1212 | neturg = 0; | |
1213 | } | |
1214 | \f | |
5d78ef73 GM |
1215 | /* |
1216 | * netflush | |
1217 | * Send as much data as possible to the network, | |
1218 | * handling requests for urgent data. | |
1219 | */ | |
1220 | ||
1221 | ||
1222 | netflush() | |
1223 | { | |
1224 | int n; | |
1225 | ||
1226 | if ((n = nfrontp - nbackp) > 0) { | |
affdaa4e GM |
1227 | /* |
1228 | * if no urgent data, or if the other side appears to be an | |
1229 | * old 4.2 client (and thus unable to survive TCP urgent data), | |
1230 | * write the entire buffer in non-OOB mode. | |
1231 | */ | |
1232 | if ((neturg == 0) || (not42 == 0)) { | |
5d78ef73 GM |
1233 | n = write(net, nbackp, n); /* normal write */ |
1234 | } else { | |
1235 | n = neturg - nbackp; | |
1236 | /* | |
1237 | * In 4.2 (and 4.3) systems, there is some question about | |
1238 | * what byte in a sendOOB operation is the "OOB" data. | |
1239 | * To make ourselves compatible, we only send ONE byte | |
1240 | * out of band, the one WE THINK should be OOB (though | |
1241 | * we really have more the TCP philosophy of urgent data | |
1242 | * rather than the Unix philosophy of OOB data). | |
1243 | */ | |
1244 | if (n > 1) { | |
1245 | n = send(net, nbackp, n-1, 0); /* send URGENT all by itself */ | |
1246 | } else { | |
1247 | n = send(net, nbackp, n, MSG_OOB); /* URGENT data */ | |
1248 | } | |
1249 | } | |
1250 | } | |
1251 | if (n < 0) { | |
1252 | if (errno == EWOULDBLOCK) | |
1253 | return; | |
1254 | /* should blow this guy away... */ | |
1255 | return; | |
1256 | } | |
1257 | nbackp += n; | |
1258 | if (nbackp >= neturg) { | |
1259 | neturg = 0; | |
1260 | } | |
1261 | if (nbackp == nfrontp) { | |
1262 | nbackp = nfrontp = netobuf; | |
1263 | } | |
1264 | } | |
66b878f6 BJ |
1265 | |
1266 | cleanup() | |
1267 | { | |
c847f2e1 KB |
1268 | char *p; |
1269 | ||
1270 | p = line + sizeof("/dev/") - 1; | |
1271 | if (logout(p)) | |
1272 | logwtmp(p, "", ""); | |
1273 | (void)chmod(line, 0666); | |
1274 | (void)chown(line, 0, 0); | |
1275 | *p = 'p'; | |
1276 | (void)chmod(line, 0666); | |
1277 | (void)chown(line, 0, 0); | |
ff24c640 | 1278 | shutdown(net, 2); |
66b878f6 BJ |
1279 | exit(1); |
1280 | } | |
1281 | ||
d0a64c71 GM |
1282 | char editedhost[32]; |
1283 | ||
1284 | edithost(pat, host) | |
1285 | register char *pat; | |
1286 | register char *host; | |
1287 | { | |
1288 | register char *res = editedhost; | |
1289 | ||
1290 | if (!pat) | |
1291 | pat = ""; | |
1292 | while (*pat) { | |
1293 | switch (*pat) { | |
1294 | ||
1295 | case '#': | |
1296 | if (*host) | |
1297 | host++; | |
1298 | break; | |
1299 | ||
1300 | case '@': | |
1301 | if (*host) | |
1302 | *res++ = *host++; | |
1303 | break; | |
1304 | ||
1305 | default: | |
1306 | *res++ = *pat; | |
1307 | break; | |
1308 | ||
1309 | } | |
1310 | if (res == &editedhost[sizeof editedhost - 1]) { | |
1311 | *res = '\0'; | |
1312 | return; | |
1313 | } | |
1314 | pat++; | |
1315 | } | |
1316 | if (*host) | |
1317 | strncpy(res, host, sizeof editedhost - (res - editedhost) - 1); | |
1318 | else | |
1319 | *res = '\0'; | |
1320 | editedhost[sizeof editedhost - 1] = '\0'; | |
1321 | } | |
1322 | ||
1323 | static char *putlocation; | |
1324 | ||
1325 | puts(s) | |
1326 | register char *s; | |
1327 | { | |
1328 | ||
1329 | while (*s) | |
1330 | putchr(*s++); | |
1331 | } | |
1332 | ||
1333 | putchr(cc) | |
1334 | { | |
1335 | *putlocation++ = cc; | |
1336 | } | |
1337 | ||
312b6ead | 1338 | putf(cp, where) |
d0a64c71 GM |
1339 | register char *cp; |
1340 | char *where; | |
d0a64c71 GM |
1341 | { |
1342 | char *slash; | |
1343 | char datebuffer[60]; | |
1344 | extern char *rindex(); | |
1345 | ||
1346 | putlocation = where; | |
1347 | ||
1348 | while (*cp) { | |
1349 | if (*cp != '%') { | |
1350 | putchr(*cp++); | |
1351 | continue; | |
1352 | } | |
1353 | switch (*++cp) { | |
1354 | ||
1355 | case 't': | |
1356 | slash = rindex(line, '/'); | |
1357 | if (slash == (char *) 0) | |
1358 | puts(line); | |
1359 | else | |
1360 | puts(&slash[1]); | |
1361 | break; | |
1362 | ||
1363 | case 'h': | |
1364 | puts(editedhost); | |
1365 | break; | |
1366 | ||
1367 | case 'd': | |
1368 | get_date(datebuffer); | |
1369 | puts(datebuffer); | |
1370 | break; | |
1371 | ||
1372 | case '%': | |
1373 | putchr('%'); | |
1374 | break; | |
1375 | } | |
1376 | cp++; | |
1377 | } | |
1378 | } |