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authorandersen <andersen@69ca8d6d-28ef-0310-b511-8ec308f3f277>2000-06-14 20:42:57 +0000
committerandersen <andersen@69ca8d6d-28ef-0310-b511-8ec308f3f277>2000-06-14 20:42:57 +0000
commit7d7a99ca6e7ee92dcd29be4ea8e7b0563ca024eb (patch)
tree672d4d34162d111ef8166bfdb45d3cad28545bd4 /networking
parentd6ff3328a280c7ea475daa52e8ae4d181c599506 (diff)
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Integrate Tomi Ollila's telnet. Costs 3k. :)
-Erik git-svn-id: svn://busybox.net/trunk/busybox@648 69ca8d6d-28ef-0310-b511-8ec308f3f277
Diffstat (limited to 'networking')
-rw-r--r--networking/telnet.c1026
1 files changed, 596 insertions, 430 deletions
diff --git a/networking/telnet.c b/networking/telnet.c
index 8b6d5f5dc..f27603527 100644
--- a/networking/telnet.c
+++ b/networking/telnet.c
@@ -1,8 +1,12 @@
1/* vi: set sw=4 ts=4: */
1/* 2/*
2 * $Id: telnet.c,v 1.3 2000/05/12 19:41:47 erik Exp $ 3 * telnet implementation for busybox
3 * Mini telnet implementation for busybox
4 * 4 *
5 * Copyright (C) 2000 by Randolph Chung <tausq@debian.org> 5 * Author: Tomi Ollila <too@iki.fi>
6 * Copyright (C) 1994-2000 by Tomi Ollila
7 *
8 * Created: Thu Apr 7 13:29:41 1994 too
9 * Last modified: Fri Jun 9 14:34:24 2000 too
6 * 10 *
7 * This program is free software; you can redistribute it and/or modify 11 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by 12 * it under the terms of the GNU General Public License as published by
@@ -18,490 +22,652 @@
18 * along with this program; if not, write to the Free Software 22 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * 24 *
21 * This version of telnet is adapted (but very heavily modified) from the 25 * HISTORY
22 * telnet in netkit-telnet 0.16, which is: 26 * Revision 3.1 1994/04/17 11:31:54 too
23 * 27 * initial revision
24 * Copyright (c) 1989 The Regents of the University of California. 28 * Modified 2000/06/13 for inclusion into BusyBox by Erik Andersen
25 * All rights reserved. 29 * <andersen@lineo.com>
26 * 30 *
27 * Original copyright notice is retained at the end of this file.
28 */ 31 */
29 32
33
30#include "internal.h" 34#include "internal.h"
31#include <stdio.h> 35#include <termios.h>
32#include <stdlib.h>
33#include <unistd.h> 36#include <unistd.h>
34#include <ctype.h>
35#include <signal.h>
36#include <errno.h> 37#include <errno.h>
37#include <netdb.h> 38#include <stdlib.h>
38#include <termios.h> 39#include <stdarg.h>
39#include <netinet/in.h> 40#include <string.h>
41#include <signal.h>
42#include <arpa/telnet.h>
40#include <sys/types.h> 43#include <sys/types.h>
41#include <sys/socket.h> 44#include <sys/socket.h>
42#include <sys/ioctl.h> 45#include <netinet/in.h>
43#define TELOPTS 46#include <netdb.h>
44#include <arpa/telnet.h> 47
45#include <arpa/inet.h> 48#if 0
49#define DOTRACE 1
50#endif
51
52#if DOTRACE
53#include <arpa/inet.h> /* for inet_ntoa()... */
54#define TRACE(x, y) do { if (x) printf y; } while (0)
55#else
56#define TRACE(x, y)
57#endif
58
59#if 0
60#define USE_POLL
61#include <sys/poll.h>
62#else
63#include <sys/time.h>
64#endif
65
66#define DATABUFSIZE 128
67#define IACBUFSIZE 128
46 68
47static int STDIN = 0; 69#define CHM_TRY 0
48static int STDOUT = 1; 70#define CHM_ON 1
49static const char *telnet_usage = "telnet host [port]\n" 71#define CHM_OFF 2
72
73#define UF_ECHO 0x01
74#define UF_SGA 0x02
75
76#define TS_0 1
77#define TS_IAC 2
78#define TS_OPT 3
79#define TS_SUB1 4
80#define TS_SUB2 5
81
82#define WriteCS(fd, str) write(fd, str, sizeof str -1)
83
84typedef unsigned char byte;
85
86/* use globals to reduce size ??? */ /* test this hypothesis later */
87struct Globalvars {
88 int netfd; /* console fd:s are 0 and 1 (and 2) */
89 /* same buffer used both for network and console read/write */
90 char * buf; /* allocating so static size is smaller */
91 short len;
92 byte telstate; /* telnet negotiation state from network input */
93 byte telwish; /* DO, DONT, WILL, WONT */
94 byte charmode;
95 byte telflags;
96 byte gotsig;
97 /* buffer to handle telnet negotiations */
98 char * iacbuf;
99 short iaclen; /* could even use byte */
100 struct termios termios_def;
101 struct termios termios_raw;
102} G;
103
104#define xUSE_GLOBALVAR_PTR /* xUSE... -> don't use :D (makes smaller code) */
105
106#ifdef USE_GLOBALVAR_PTR
107struct Globalvars * Gptr;
108#define G (*Gptr)
109#else
110struct Globalvars G;
111#endif
112
113static inline void iacflush()
114{
115 write(G.netfd, G.iacbuf, G.iaclen);
116 G.iaclen = 0;
117}
118
119/* Function prototypes */
120static int getport(char * p);
121static struct in_addr getserver(char * p);
122static int create_socket();
123static void setup_sockaddr_in(struct sockaddr_in * addr, int port);
124static int remote_connect(struct in_addr addr, int port);
125static void rawmode();
126static void cookmode();
127static void do_linemode();
128static void will_charmode();
129static void telopt(byte c);
130static int subneg(byte c);
131#if 0
132static int local_bind(int port);
133#endif
134
135/* Some globals */
136static int one = 1;
137static const char telnet_usage[] =
138 "telnet host [port]\n"
50#ifndef BB_FEATURE_TRIVIAL_HELP 139#ifndef BB_FEATURE_TRIVIAL_HELP
51 "\nProvides interactive communication with another\n" 140 "\nTelnet is used to establish interactive communication with another\n"
52 "networked host using the TELNET protocol\n" 141 "computer over a network using the TELNET protocol.\n"
53#endif 142#endif
54 ; 143 ;
55static struct termios saved_tc; 144
56static unsigned char options[NTELOPTS]; 145
57static char tr_state = 0; /* telnet send and receive state */ 146static void doexit(int ev)
58static unsigned char subbuffer[256]; 147{
59static unsigned char *subpointer, *subend; 148 cookmode();
60#define SB_CLEAR() subpointer = subbuffer; 149 exit(ev);
61#define SB_TERM() { subend = subpointer; SB_CLEAR(); } 150}
62#define SB_ACCUM(c) if (subpointer < (subbuffer+sizeof subbuffer)) { *subpointer++ = (c); } 151
63#define SB_GET() (*subpointer++) 152static void conescape()
64#define SB_PEEK() (*subpointer) 153{
65#define SB_EOF() (subpointer >= subend) 154 char b;
66#define SB_LEN() (subend - subpointer) 155
67 156 if (G.gotsig) /* came from line mode... go raw */
68#define TELNETPORT 23 157 rawmode();
69#define MASK_WILL 0x01 158
70#define MASK_WONT 0x04 159 WriteCS(1, "\r\nConsole escape. Commands are:\r\n\n"
71#define MASK_DO 0x10 160 " l go to line mode\r\n"
72#define MASK_DONT 0x40 161 " c go to character mode\r\n"
73 162 " z suspend telnet\r\n"
74#define TFLAG_ISSET(opt, flag) (options[opt] & MASK_##flag) 163 " e exit telnet\r\n");
75#define TFLAG_SET(opt, flag) (options[opt] |= MASK_##flag) 164
76#define TFLAG_CLR(opt, flag) (options[opt] &= ~MASK_##flag) 165 if (read(0, &b, 1) <= 0)
77 166 doexit(1);
78#define PERROR(ctx) do { fprintf(stderr, "%s: %s\n", ctx, strerror(errno)); \ 167
79 return; } while (0) 168 switch (b)
80 169 {
81#define TS_DATA 0 170 case 'l':
82#define TS_IAC 1 171 if (!G.gotsig)
83#define TS_WILL 2 172 {
84#define TS_WONT 3 173 do_linemode();
85#define TS_DO 4 174 goto rrturn;
86#define TS_DONT 5 175 }
87#define TS_CR 6 176 break;
88#define TS_SB 7 /* sub-option collection */ 177 case 'c':
89#define TS_SE 8 /* looking for sub-option end */ 178 if (G.gotsig)
90 179 {
91/* prototypes */ 180 will_charmode();
92static void telnet_init(void); 181 goto rrturn;
93static void telnet_start(char *host, int port); 182 }
94static void telnet_shutdown(void); 183 break;
95/* ******************************************************************* */ 184 case 'z':
96#define SENDCOMMAND(c,o) \ 185 cookmode();
97 char buf[3]; \ 186 kill(0, SIGTSTP);
98 buf[0] = IAC; buf[1] = c; buf[2] = o; \ 187 rawmode();
99 write(s, buf, sizeof(buf)); 188 break;
100 189 case 'e':
101static inline void telnet_sendwill(int s, int c) { SENDCOMMAND(WILL, c); } 190 doexit(0);
102static inline void telnet_sendwont(int s, int c) { SENDCOMMAND(WONT, c); } 191 }
103static inline void telnet_senddo(int s, int c) { SENDCOMMAND(DO, c); } 192
104static inline void telnet_senddont(int s, int c) { SENDCOMMAND(DONT, c); } 193 WriteCS(1, "continuing...\r\n");
105 194
106static void telnet_setoptions(int s) 195 if (G.gotsig)
196 cookmode();
197
198 rrturn:
199 G.gotsig = 0;
200
201}
202static void handlenetoutput()
107{ 203{
108 /* 204 /* here we could do smart tricks how to handle 0xFF:s in output
109 telnet_sendwill(s, TELOPT_NAWS); TFLAG_SET(TELOPT_NAWS, WILL); 205 * stream like writing twice every sequence of FF:s (thus doing
110 telnet_sendwill(s, TELOPT_TSPEED); TFLAG_SET(TELOPT_TSPEED, WILL); 206 * many write()s. But I think interactive telnet application does
111 telnet_sendwill(s, TELOPT_NEW_ENVIRON); TFLAG_SET(TELOPT_NEW_ENVIRON, WILL); 207 * not need to be 100% 8-bit clean, so changing every 0xff:s to
112 telnet_senddo(s, TELOPT_STATUS); TFLAG_SET(TELOPT_STATUS, DO); 208 * 0x7f:s */
113 telnet_sendwill(s, TELOPT_TTYPE); TFLAG_SET(TELOPT_TTYPE, WILL); 209
114 */ 210 int i;
115 telnet_senddo(s, TELOPT_SGA); TFLAG_SET(TELOPT_SGA, DO); 211 byte * p = G.buf;
116 telnet_sendwill(s, TELOPT_LFLOW); TFLAG_SET(TELOPT_LFLOW, WILL); 212
117 telnet_sendwill(s, TELOPT_LINEMODE); TFLAG_SET(TELOPT_LINEMODE, WILL); 213 for (i = G.len; i > 0; i--, p++)
118 telnet_senddo(s, TELOPT_BINARY); TFLAG_SET(TELOPT_BINARY, DO); 214 {
119 telnet_sendwill(s, TELOPT_BINARY); TFLAG_SET(TELOPT_BINARY, WILL); 215 if (*p == 0x1d)
216 {
217 conescape();
218 return;
219 }
220 if (*p == 0xff)
221 *p = 0x7f;
222 }
223 write(G.netfd, G.buf, G.len);
120} 224}
121 225
122static void telnet_suboptions(int net) 226
227static void handlenetinput()
123{ 228{
124 char buf[256]; 229 int i;
125 switch (SB_GET()) { 230 int cstart = 0;
126 case TELOPT_TTYPE: 231
127 if (TFLAG_ISSET(TELOPT_TTYPE, WONT)) return; 232 for (i = 0; i < G.len; i++)
128 if (SB_EOF() || SB_GET() != TELQUAL_SEND) { 233 {
129 return; 234 byte c = G.buf[i];
130 } else { 235
131 const char *name = getenv("TERM"); 236 if (G.telstate == 0) /* most of the time state == 0 */
132 if (name) { 237 {
133 snprintf(buf, sizeof(buf), "%c%c%c%c%s%c%c", IAC, SB, 238 if (c == IAC)
134 TELOPT_TTYPE, TELQUAL_IS, name, IAC, SE); 239 {
135 write(net, buf, strlen(name)+6); 240 cstart = i;
136 } 241 G.telstate = TS_IAC;
137 }
138 break;
139 case TELOPT_TSPEED:
140 if (TFLAG_ISSET(TELOPT_TSPEED, WONT)) return;
141 if (SB_EOF()) return;
142 if (SB_GET() == TELQUAL_SEND) {
143 /*
144 long oospeed, iispeed;
145 netoring.printf("%c%c%c%c%ld,%ld%c%c", IAC, SB, TELOPT_TSPEED,
146 TELQUAL_IS, oospeed, iispeed, IAC, SE);
147 */
148 }
149 break;
150 /*
151 case TELOPT_LFLOW:
152 if (TFLAG_ISSET(TELOPT_LFLOW, WONT)) return;
153 if (SB_EOF()) return;
154 switch(SB_GET()) {
155 case 1: localflow = 1; break;
156 case 0: localflow = 0; break;
157 default: return;
158 }
159 break;
160 case TELOPT_LINEMODE:
161 if (TFLAG_ISSET(TELOPT_LINEMODE, WONT)) return;
162 if (SB_EOF()) return;
163 switch (SB_GET()) {
164 case WILL: lm_will(subpointer, SB_LEN()); break;
165 case WONT: lm_wont(subpointer, SB_LEN()); break;
166 case DO: lm_do(subpointer, SB_LEN()); break;
167 case DONT: lm_dont(subpointer, SB_LEN()); break;
168 case LM_SLC: slc(subpointer, SB_LEN()); break;
169 case LM_MODE: lm_mode(subpointer, SB_LEN(), 0); break;
170 default: break;
171 }
172 break;
173 case TELOPT_ENVIRON:
174 if (SB_EOF()) return;
175 switch(SB_PEEK()) {
176 case TELQUAL_IS:
177 case TELQUAL_INFO:
178 if (TFLAG_ISSET(TELOPT_ENVIRON, DONT)) return;
179 break;
180 case TELQUAL_SEND:
181 if (TFLAG_ISSET(TELOPT_ENVIRON, WONT)) return;
182 break;
183 default:
184 return;
185 }
186 env_opt(subpointer, SB_LEN());
187 break;
188 */
189 case TELOPT_XDISPLOC:
190 if (TFLAG_ISSET(TELOPT_XDISPLOC, WONT)) return;
191 if (SB_EOF()) return;
192 if (SB_GET() == TELQUAL_SEND) {
193 const char *dp = getenv("DISPLAY");
194 if (dp) {
195 snprintf(buf, sizeof(buf), "%c%c%c%c%s%c%c", IAC, SB,
196 TELOPT_XDISPLOC, TELQUAL_IS, dp, IAC, SE);
197 write(net, buf, strlen(dp)+6);
198 }
199 } 242 }
200 break; 243 }
201 default: 244 else
202 break; 245 switch (G.telstate)
246 {
247 case TS_0:
248 if (c == IAC)
249 G.telstate = TS_IAC;
250 else
251 G.buf[cstart++] = c;
252 break;
253
254 case TS_IAC:
255 if (c == IAC) /* IAC IAC -> 0xFF */
256 {
257 G.buf[cstart++] = c;
258 G.telstate = TS_0;
259 break;
260 }
261 /* else */
262 switch (c)
263 {
264 case SB:
265 G.telstate = TS_SUB1;
266 break;
267 case DO:
268 case DONT:
269 case WILL:
270 case WONT:
271 G.telwish = c;
272 G.telstate = TS_OPT;
273 break;
274 default:
275 G.telstate = TS_0; /* DATA MARK must be added later */
276 }
277 break;
278 case TS_OPT: /* WILL, WONT, DO, DONT */
279 telopt(c);
280 G.telstate = TS_0;
281 break;
282 case TS_SUB1: /* Subnegotiation */
283 case TS_SUB2: /* Subnegotiation */
284 if (subneg(c) == TRUE)
285 G.telstate = TS_0;
286 break;
287 }
203 } 288 }
289 if (G.telstate)
290 {
291 if (G.iaclen) iacflush();
292 if (G.telstate == TS_0) G.telstate = 0;
293
294 G.len = cstart;
295 }
296
297 if (G.len)
298 write(1, G.buf, G.len);
204} 299}
205 300
206static void sighandler(int sig) 301
302/* ******************************* */
303
304static inline void putiac(int c)
207{ 305{
208 telnet_shutdown(); 306 G.iacbuf[G.iaclen++] = c;
209 exit(0);
210} 307}
211 308
212static int telnet_send(int tty, int net) 309
310static void putiac2(byte wwdd, byte c)
213{ 311{
214 int ret; 312 if (G.iaclen + 3 > IACBUFSIZE)
215 unsigned char ch; 313 iacflush();
216 314
217 while ((ret = read(tty, &ch, 1)) > 0) { 315 putiac(IAC);
218 if (ch == 29) { /* 29 -- ctrl-] */ 316 putiac(wwdd);
219 /* do something here? */ 317 putiac(c);
220 exit(0); 318}
221 } else { 319
222 ret = write(net, &ch, 1); 320#if 0
223 break; 321static void putiac1(byte c)
322{
323 if (G.iaclen + 2 > IACBUFSIZE)
324 iacflush();
325
326 putiac(IAC);
327 putiac(c);
328}
329#endif
330
331/* void putiacstring (subneg strings) */
332
333/* ******************************* */
334
335char const escapecharis[] = "\r\nEscape character is ";
336
337static void setConMode()
338{
339 if (G.telflags & UF_ECHO)
340 {
341 if (G.charmode == CHM_TRY) {
342 G.charmode = CHM_ON;
343 fprintf(stdout, "\r\nEntering character mode%s'^]'.\r\n", escapecharis);
344 rawmode();
345 }
346 }
347 else
348 {
349 if (G.charmode != CHM_OFF) {
350 G.charmode = CHM_OFF;
351 fprintf(stdout, "\r\nEntering line mode%s'^C'.\r\n", escapecharis);
352 cookmode();
224 } 353 }
225 } 354 }
226 if (ret == -1 && errno == EWOULDBLOCK) return 1;
227 return ret;
228} 355}
229 356
230static int telnet_recv(int net, int tty) 357/* ******************************* */
358
359static void will_charmode()
231{ 360{
232 /* globals: tr_state - telnet receive state */ 361 G.charmode = CHM_TRY;
233 int ret, c = 0; 362 G.telflags |= (UF_ECHO | UF_SGA);
234 unsigned char ch; 363 setConMode();
235 364
236 while ((ret = read(net, &ch, 1)) > 0) { 365 putiac2(DO, TELOPT_ECHO);
237 c = ch; 366 putiac2(DO, TELOPT_SGA);
238 /* printf("%02X ", c); fflush(stdout); */ 367 iacflush();
239 switch (tr_state) { 368}
240 case TS_DATA: 369
241 if (c == IAC) { 370static void do_linemode()
242 tr_state = TS_IAC; 371{
243 break; 372 G.charmode = CHM_TRY;
244 } else { 373 G.telflags &= ~(UF_ECHO | UF_SGA);
245 write(tty, &c, 1); 374 setConMode();
246 } 375
247 break; 376 putiac2(DONT, TELOPT_ECHO);
248 case TS_IAC: 377 putiac2(DONT, TELOPT_SGA);
249 switch (c) { 378 iacflush();
250 case WILL: 379}
251 tr_state = TS_WILL; break; 380
252 case WONT: 381/* ******************************* */
253 tr_state = TS_WONT; break; 382
254 case DO: 383static inline void to_notsup(char c)
255 tr_state = TS_DO; break; 384{
256 case DONT: 385 if (G.telwish == WILL) putiac2(DONT, c);
257 tr_state = TS_DONT; break; 386 else if (G.telwish == DO) putiac2(WONT, c);
258 case SB: 387}
259 SB_CLEAR(); 388
260 tr_state = TS_SB; break; 389static inline void to_echo()
261 case IAC: 390{
262 write(tty, &c, 1); /* fallthrough */ 391 /* if server requests ECHO, don't agree */
263 default: 392 if (G.telwish == DO) { putiac2(WONT, TELOPT_ECHO); return; }
264 tr_state = TS_DATA; 393 else if (G.telwish == DONT) return;
265 } 394
266 395 if (G.telflags & UF_ECHO)
267 /* subnegotiation -- ignored for now */ 396 {
268 case TS_SB: 397 if (G.telwish == WILL)
269 if (c == IAC) tr_state = TS_SE; 398 return;
270 else SB_ACCUM(c);
271 break;
272 case TS_SE:
273 if (c == IAC) {
274 SB_ACCUM(IAC);
275 tr_state = TS_SB;
276 } else if (c == SE) {
277 SB_ACCUM(IAC);
278 SB_ACCUM(SE);
279 subpointer -= 2;
280 SB_TERM();
281 telnet_suboptions(net);
282 tr_state = TS_DATA;
283 }
284 /* otherwise this is an error, but we ignore it for now */
285 break;
286 /* handle incoming requests */
287 case TS_WILL:
288 printf("WILL %s\n", telopts[c]);
289 if (!TFLAG_ISSET(c, DO)) {
290 if (c == TELOPT_BINARY) {
291 TFLAG_SET(c, DO);
292 TFLAG_CLR(c, DONT);
293 telnet_senddo(net, c);
294 } else {
295 TFLAG_SET(c, DONT);
296 telnet_senddont(net, c);
297 }
298 }
299 telnet_senddont(net, c);
300 tr_state = TS_DATA;
301 break;
302 case TS_WONT:
303 printf("WONT %s\n", telopts[c]);
304 if (!TFLAG_ISSET(c, DONT)) {
305 TFLAG_SET(c, DONT);
306 TFLAG_CLR(c, DO);
307 telnet_senddont(net, c);
308 }
309 tr_state = TS_DATA;
310 break;
311 case TS_DO:
312 printf("DO %s\n", telopts[c]);
313 if (!TFLAG_ISSET(c, WILL)) {
314 if (c == TELOPT_BINARY) {
315 TFLAG_SET(c, WILL);
316 TFLAG_CLR(c, WONT);
317 telnet_sendwill(net, c);
318 } else {
319 TFLAG_SET(c, WONT);
320 telnet_sendwont(net, c);
321 }
322 }
323 tr_state = TS_DATA;
324 break;
325 case TS_DONT:
326 printf("DONT %s\n", telopts[c]);
327 if (!TFLAG_ISSET(c, WONT)) {
328 TFLAG_SET(c, WONT);
329 TFLAG_CLR(c, WILL);
330 telnet_sendwont(net, c);
331 }
332 tr_state = TS_DATA;
333 break;
334 }
335
336 } 399 }
337 if (ret == -1 && errno == EWOULDBLOCK) return 1; 400 else
338 return ret; 401 if (G.telwish == WONT)
402 return;
403
404 if (G.charmode != CHM_OFF)
405 G.telflags ^= UF_ECHO;
406
407 if (G.telflags & UF_ECHO)
408 putiac2(DO, TELOPT_ECHO);
409 else
410 putiac2(DONT, TELOPT_ECHO);
411
412 setConMode();
413 WriteCS(1, "\r\n"); /* sudden modec */
339} 414}
340 415
341/* ******************************************************************* */ 416static inline void to_sga()
342static void telnet_init(void)
343{ 417{
344 struct termios tmp_tc; 418 /* daemon always sends will/wont, client do/dont */
345 cc_t esc = (']' & 0x1f); /* ctrl-] */ 419
346 420 if (G.telflags & UF_SGA)
347 memset(options, 0, sizeof(options)); 421 {
348 SB_CLEAR(); 422 if (G.telwish == WILL)
349 423 return;
350 tcgetattr(STDIN, &saved_tc); 424 }
351 425 else
352 tmp_tc = saved_tc; 426 if (G.telwish == WONT)
353 tmp_tc.c_lflag &= ~ECHO; /* echo */ 427 return;
354 tmp_tc.c_oflag |= ONLCR; /* NL->CRLF translation */ 428
355 tmp_tc.c_iflag |= ICRNL; 429 if ((G.telflags ^= UF_SGA) & UF_SGA) /* toggle */
356 tmp_tc.c_iflag &= ~(IXANY|IXOFF|IXON); /* no flow control */ 430 putiac2(DO, TELOPT_SGA);
357 tmp_tc.c_lflag |= ISIG; /* trap signals */ 431 else
358 tmp_tc.c_lflag &= ~ICANON; /* edit mode */ 432 putiac2(DONT, TELOPT_SGA);
359 433
360 /* misc settings, compat with default telnet stuff */ 434 return;
361 tmp_tc.c_oflag &= ~TABDLY;
362
363 /* 8-bit clean */
364 tmp_tc.c_iflag &= ~ISTRIP;
365 tmp_tc.c_cflag &= ~(CSIZE|PARENB);
366 tmp_tc.c_cflag |= saved_tc.c_cflag & (CSIZE|PARENB);
367 tmp_tc.c_oflag |= OPOST;
368
369 /* set escape character */
370 tmp_tc.c_cc[VEOL] = esc;
371 tcsetattr(STDIN, TCSADRAIN, &tmp_tc);
372} 435}
373 436
374static void telnet_start(char *hostname, int port) 437static void telopt(byte c)
375{ 438{
376 struct hostent *host = 0; 439 switch (c)
377 struct sockaddr_in addr; 440 {
378 int s, c; 441 case TELOPT_ECHO: to_echo(c); break;
379 fd_set rfds, wfds; 442 case TELOPT_SGA: to_sga(c); break;
380 443 default: to_notsup(c); break;
381 memset(&addr, 0, sizeof(addr));
382 host = gethostbyname(hostname);
383 if (!host) {
384 fprintf(stderr, "Unknown host: %s\n", hostname);
385 return;
386 } 444 }
387 addr.sin_family = host->h_addrtype; 445}
388 memcpy(&addr.sin_addr, host->h_addr, sizeof(addr.sin_addr)); 446
389 addr.sin_port = htons(port); 447
448/* ******************************* */
390 449
391 printf("Trying %s...\n", inet_ntoa(addr.sin_addr)); 450/* subnegotiation -- ignore all */
451
452static int subneg(byte c)
453{
454 switch (G.telstate)
455 {
456 case TS_SUB1:
457 if (c == IAC)
458 G.telstate = TS_SUB2;
459 break;
460 case TS_SUB2:
461 if (c == SE)
462 return TRUE;
463 G.telstate = TS_SUB1;
464 /* break; */
465 }
466 return FALSE;
467}
468
469/* ******************************* */
470
471static void fgotsig(int sig)
472{
473 G.gotsig = sig;
474}
475
476
477static void rawmode()
478{
479 tcsetattr(0, TCSADRAIN, &G.termios_raw);
480}
481
482static void cookmode()
483{
484 tcsetattr(0, TCSADRAIN, &G.termios_def);
485}
486
487extern int telnet_main(int argc, char** argv)
488{
489 struct in_addr host;
490 int port;
491#ifdef USE_POLL
492 struct pollfd ufds[2];
493#else
494 fd_set readfds;
495 int maxfd;
496#endif
497
498
499 memset(&G, 0, sizeof G);
500
501 if (tcgetattr(0, &G.termios_def) < 0)
502 exit(1);
392 503
393 if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) PERROR("socket"); 504 G.termios_raw = G.termios_def;
394 if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) 505
395 PERROR("connect"); 506 cfmakeraw(&G.termios_raw);
396 printf("Connected to %s\n", hostname);
397 printf("Escape character is ^]\n");
398
399 signal(SIGINT, sighandler);
400 signal(SIGQUIT, sighandler);
401 signal(SIGPIPE, sighandler);
402 signal(SIGWINCH, sighandler);
403
404 /* make inputs nonblocking */
405 c = 1;
406 ioctl(s, FIONBIO, &c);
407 ioctl(STDIN, FIONBIO, &c);
408 507
409 if (port == TELNETPORT) telnet_setoptions(s); 508 if (argc < 2) usage(telnet_usage);
509 port = (argc > 2)? getport(argv[2]): 23;
410 510
411 /* shuttle data back and forth between tty and socket */ 511 G.buf = xmalloc(DATABUFSIZE);
412 while (1) { 512 G.iacbuf = xmalloc(IACBUFSIZE);
413 FD_ZERO(&rfds);
414 FD_ZERO(&wfds);
415 513
416 FD_SET(s, &rfds); 514 host = getserver(argv[1]);
417 /* FD_SET(s, &wfds); */ 515
418 FD_SET(STDIN, &rfds); 516 G.netfd = remote_connect(host, port);
419 /* FD_SET(STDOUT, &wfds); */ 517
518 signal(SIGINT, fgotsig);
519
520#ifdef USE_POLL
521 ufds[0].fd = 0; ufds[1].fd = G.netfd;
522 ufds[0].events = ufds[1].events = POLLIN;
523#else
524 FD_ZERO(&readfds);
525 FD_SET(0, &readfds);
526 FD_SET(G.netfd, &readfds);
527 maxfd = G.netfd + 1;
528#endif
420 529
421 if ((c = select(s+1, &rfds, &wfds, 0, 0))) { 530 while (1)
422 if (c == -1) { 531 {
423 /* handle errors */ 532#ifndef USE_POLL
424 PERROR("select"); 533 fd_set rfds = readfds;
425 } 534
426 if (FD_ISSET(s, &rfds)) { 535 switch (select(maxfd, &rfds, NULL, NULL, NULL))
427 /* input from network */ 536#else
428 FD_CLR(s, &rfds); 537 switch (poll(ufds, 2, -1))
429 c = telnet_recv(s, STDOUT); 538#endif
430 if (c == 0) break; 539 {
431 if (c < 0) PERROR("telnet_recv"); 540 case 0:
541 /* timeout */
542 case -1:
543 /* error, ignore and/or log something, bay go to loop */
544 if (G.gotsig)
545 conescape();
546 else
547 sleep(1);
548 break;
549 default:
550
551#ifdef USE_POLL
552 if (ufds[0].revents) /* well, should check POLLIN, but ... */
553#else
554 if (FD_ISSET(0, &rfds))
555#endif
556 {
557 G.len = read(0, G.buf, DATABUFSIZE);
558
559 if (G.len <= 0)
560 doexit(0);
561
562 TRACE(0, ("Read con: %d\n", G.len));
563
564 handlenetoutput();
432 } 565 }
433 if (FD_ISSET(STDIN, &rfds)) { 566
434 /* input from tty */ 567#ifdef USE_POLL
435 FD_CLR(STDIN, &rfds); 568 if (ufds[1].revents) /* well, should check POLLIN, but ... */
436 c = telnet_send(STDIN, s); 569#else
437 if (c == 0) break; 570 if (FD_ISSET(G.netfd, &rfds))
438 if (c < 0) PERROR("telnet_send"); 571#endif
572 {
573 G.len = read(G.netfd, G.buf, DATABUFSIZE);
574
575 if (G.len <= 0)
576 {
577 WriteCS(1, "Connection closed by foreign host.\r\n");
578 doexit(1);
579 }
580 TRACE(0, ("Read netfd (%d): %d\n", G.netfd, G.len));
581
582 handlenetinput();
439 } 583 }
440 } 584 }
441 } 585 }
442
443 return;
444} 586}
445 587
446static void telnet_shutdown(void) 588static int getport(char * p)
447{ 589{
448 printf("\n"); 590 unsigned int port = atoi(p);
449 tcsetattr(STDIN, TCSANOW, &saved_tc); 591
592 if ((unsigned)(port - 1 ) > 65534)
593 {
594 fatalError("%s: bad port number\n", p);
595 }
596 return port;
450} 597}
451 598
452#ifdef STANDALONE_TELNET 599static struct in_addr getserver(char * host)
453void usage(const char *msg)
454{ 600{
455 printf("%s", msg); 601 struct in_addr addr;
456 exit(0); 602
603 struct hostent * he;
604 if ((he = gethostbyname(host)) == NULL)
605 {
606 fatalError("%s: Unkonwn host\n", host);
607 }
608 memcpy(&addr, he->h_addr, sizeof addr);
609
610 TRACE(1, ("addr: %s\n", inet_ntoa(addr)));
611
612 return addr;
613}
614
615static int create_socket()
616{
617 return socket(AF_INET, SOCK_STREAM, 0);
457} 618}
458 619
459int main(int argc, char **argv) 620static void setup_sockaddr_in(struct sockaddr_in * addr, int port)
460#else 621{
461int telnet_main(int argc, char **argv) 622 memset(addr, 0, sizeof addr);
462#endif 623 addr->sin_family = AF_INET;
624 addr->sin_port = htons(port);
625}
626
627#if 0
628static int local_bind(int port)
463{ 629{
464 int port = TELNETPORT; 630 struct sockaddr_in s_addr;
631 int s = create_socket();
632
633 setup_sockaddr_in(&s_addr, port);
634
635 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
636
637 if (bind(s, &s_addr, sizeof s_addr) < 0)
638 {
639 char * e = sys_errlist[errno];
640 syserrorexit("bind");
641 exit(1);
642 }
643 listen(s, 1);
465 644
466 argc--; argv++; 645 return s;
467 if (argc < 1) usage(telnet_usage); 646}
468 if (argc > 1) port = atoi(argv[1]); 647#endif
469 telnet_init(); 648
470 atexit(telnet_shutdown); 649static int remote_connect(struct in_addr addr, int port)
471 650{
472 telnet_start(argv[0], port); 651 struct sockaddr_in s_addr;
473 return 0; 652 int s = create_socket();
653
654 setup_sockaddr_in(&s_addr, port);
655 s_addr.sin_addr = addr;
656
657 setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof one);
658
659 if (connect(s, (struct sockaddr *)&s_addr, sizeof s_addr) < 0)
660 {
661 fatalError("Unable to connect to remote host: %s\n", strerror(errno));
662 }
663 return s;
474} 664}
475 665
476/* 666/*
477 * Copyright (c) 1988, 1990 Regents of the University of California. 667Local Variables:
478 * All rights reserved. 668c-file-style: "linux"
479 * 669c-basic-offset: 4
480 * Redistribution and use in source and binary forms, with or without 670tab-width: 4
481 * modification, are permitted provided that the following conditions 671End:
482 * are met: 672*/
483 * 1. Redistributions of source code must retain the above copyright 673
484 * notice, this list of conditions and the following disclaimer.
485 * 2. Redistributions in binary form must reproduce the above copyright
486 * notice, this list of conditions and the following disclaimer in the
487 * documentation and/or other materials provided with the distribution.
488 * 3. All advertising materials mentioning features or use of this software
489 * must display the following acknowledgement:
490 * This product includes software developed by the University of
491 * California, Berkeley and its contributors.
492 * 4. Neither the name of the University nor the names of its contributors
493 * may be used to endorse or promote products derived from this software
494 * without specific prior written permission.
495 *
496 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
497 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
498 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
499 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
500 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
501 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
502 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
503 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
504 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
505 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
506 * SUCH DAMAGE.
507 */
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