+/* vi: set sw=4 ts=4: */
/*
- * $Id: telnet.c,v 1.3 2000/05/12 19:41:47 erik Exp $
- * Mini telnet implementation for busybox
+ * telnet implementation for busybox
*
- * Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
+ * Author: Tomi Ollila <too@iki.fi>
+ * Copyright (C) 1994-2000 by Tomi Ollila
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * Created: Thu Apr 7 13:29:41 1994 too
+ * Last modified: Fri Jun 9 14:34:24 2000 too
*
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * HISTORY
+ * Revision 3.1 1994/04/17 11:31:54 too
+ * initial revision
+ * Modified 2000/06/13 for inclusion into BusyBox by Erik Andersen <andersen@codepoet.org>
+ * Modified 2001/05/07 to add ability to pass TTYPE to remote host by Jim McQuillan
+ * <jam@ltsp.org>
+ * Modified 2004/02/11 to add ability to pass the USER variable to remote host
+ * by Fernando Silveira <swrh@gmx.net>
*
- * This version of telnet is adapted (but very heavily modified) from the
- * telnet in netkit-telnet 0.16, which is:
- *
- * Copyright (c) 1989 The Regents of the University of California.
- * All rights reserved.
- *
- * Original copyright notice is retained at the end of this file.
*/
-#include "internal.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <ctype.h>
-#include <signal.h>
-#include <errno.h>
-#include <netdb.h>
-#include <termios.h>
-#include <netinet/in.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/ioctl.h>
-#define TELOPTS
+//usage:#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+//usage:#define telnet_trivial_usage
+//usage: "[-a] [-l USER] HOST [PORT]"
+//usage:#define telnet_full_usage "\n\n"
+//usage: "Connect to telnet server\n"
+//usage: "\n -a Automatic login with $USER variable"
+//usage: "\n -l USER Automatic login as USER"
+//usage:
+//usage:#else
+//usage:#define telnet_trivial_usage
+//usage: "HOST [PORT]"
+//usage:#define telnet_full_usage "\n\n"
+//usage: "Connect to telnet server"
+//usage:#endif
+
#include <arpa/telnet.h>
-#include <arpa/inet.h>
-
-static int STDIN = 0;
-static int STDOUT = 1;
-static const char *telnet_usage = "telnet host [port]\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
- "\nProvides interactive communication with another\n"
- "networked host using the TELNET protocol\n"
+#include <netinet/in.h>
+#include "libbb.h"
+
+#ifdef __BIONIC__
+/* should be in arpa/telnet.h */
+# define IAC 255 /* interpret as command: */
+# define DONT 254 /* you are not to use option */
+# define DO 253 /* please, you use option */
+# define WONT 252 /* I won't use option */
+# define WILL 251 /* I will use option */
+# define SB 250 /* interpret as subnegotiation */
+# define SE 240 /* end sub negotiation */
+# define TELOPT_ECHO 1 /* echo */
+# define TELOPT_SGA 3 /* suppress go ahead */
+# define TELOPT_TTYPE 24 /* terminal type */
+# define TELOPT_NAWS 31 /* window size */
#endif
- ;
-static struct termios saved_tc;
-static unsigned char options[NTELOPTS];
-static char tr_state = 0; /* telnet send and receive state */
-static unsigned char subbuffer[256];
-static unsigned char *subpointer, *subend;
-#define SB_CLEAR() subpointer = subbuffer;
-#define SB_TERM() { subend = subpointer; SB_CLEAR(); }
-#define SB_ACCUM(c) if (subpointer < (subbuffer+sizeof subbuffer)) { *subpointer++ = (c); }
-#define SB_GET() (*subpointer++)
-#define SB_PEEK() (*subpointer)
-#define SB_EOF() (subpointer >= subend)
-#define SB_LEN() (subend - subpointer)
-
-#define TELNETPORT 23
-#define MASK_WILL 0x01
-#define MASK_WONT 0x04
-#define MASK_DO 0x10
-#define MASK_DONT 0x40
-
-#define TFLAG_ISSET(opt, flag) (options[opt] & MASK_##flag)
-#define TFLAG_SET(opt, flag) (options[opt] |= MASK_##flag)
-#define TFLAG_CLR(opt, flag) (options[opt] &= ~MASK_##flag)
-
-#define PERROR(ctx) do { fprintf(stderr, "%s: %s\n", ctx, strerror(errno)); \
- return; } while (0)
-
-#define TS_DATA 0
-#define TS_IAC 1
-#define TS_WILL 2
-#define TS_WONT 3
-#define TS_DO 4
-#define TS_DONT 5
-#define TS_CR 6
-#define TS_SB 7 /* sub-option collection */
-#define TS_SE 8 /* looking for sub-option end */
-
-/* prototypes */
-static void telnet_init(void);
-static void telnet_start(char *host, int port);
-static void telnet_shutdown(void);
-/* ******************************************************************* */
-#define SENDCOMMAND(c,o) \
- char buf[3]; \
- buf[0] = IAC; buf[1] = c; buf[2] = o; \
- write(s, buf, sizeof(buf));
-
-static inline void telnet_sendwill(int s, int c) { SENDCOMMAND(WILL, c); }
-static inline void telnet_sendwont(int s, int c) { SENDCOMMAND(WONT, c); }
-static inline void telnet_senddo(int s, int c) { SENDCOMMAND(DO, c); }
-static inline void telnet_senddont(int s, int c) { SENDCOMMAND(DONT, c); }
-
-static void telnet_setoptions(int s)
+
+#ifdef DOTRACE
+# define TRACE(x, y) do { if (x) printf y; } while (0)
+#else
+# define TRACE(x, y)
+#endif
+
+enum {
+ DATABUFSIZE = 128,
+ IACBUFSIZE = 128,
+
+ CHM_TRY = 0,
+ CHM_ON = 1,
+ CHM_OFF = 2,
+
+ UF_ECHO = 0x01,
+ UF_SGA = 0x02,
+
+ TS_NORMAL = 0,
+ TS_COPY = 1,
+ TS_IAC = 2,
+ TS_OPT = 3,
+ TS_SUB1 = 4,
+ TS_SUB2 = 5,
+ TS_CR = 6,
+};
+
+typedef unsigned char byte;
+
+enum { netfd = 3 };
+
+struct globals {
+ int iaclen; /* could even use byte, but it's a loss on x86 */
+ byte telstate; /* telnet negotiation state from network input */
+ byte telwish; /* DO, DONT, WILL, WONT */
+ byte charmode;
+ byte telflags;
+ byte do_termios;
+#if ENABLE_FEATURE_TELNET_TTYPE
+ char *ttype;
+#endif
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+ const char *autologin;
+#endif
+#if ENABLE_FEATURE_AUTOWIDTH
+ unsigned win_width, win_height;
+#endif
+ /* same buffer used both for network and console read/write */
+ char buf[DATABUFSIZE];
+ /* buffer to handle telnet negotiations */
+ char iacbuf[IACBUFSIZE];
+ struct termios termios_def;
+ struct termios termios_raw;
+} FIX_ALIASING;
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define INIT_G() do { \
+ struct G_sizecheck { \
+ char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
+ }; \
+} while (0)
+
+
+static void rawmode(void);
+static void cookmode(void);
+static void do_linemode(void);
+static void will_charmode(void);
+static void telopt(byte c);
+static void subneg(byte c);
+
+static void iac_flush(void)
{
- /*
- telnet_sendwill(s, TELOPT_NAWS); TFLAG_SET(TELOPT_NAWS, WILL);
- telnet_sendwill(s, TELOPT_TSPEED); TFLAG_SET(TELOPT_TSPEED, WILL);
- telnet_sendwill(s, TELOPT_NEW_ENVIRON); TFLAG_SET(TELOPT_NEW_ENVIRON, WILL);
- telnet_senddo(s, TELOPT_STATUS); TFLAG_SET(TELOPT_STATUS, DO);
- telnet_sendwill(s, TELOPT_TTYPE); TFLAG_SET(TELOPT_TTYPE, WILL);
- */
- telnet_senddo(s, TELOPT_SGA); TFLAG_SET(TELOPT_SGA, DO);
- telnet_sendwill(s, TELOPT_LFLOW); TFLAG_SET(TELOPT_LFLOW, WILL);
- telnet_sendwill(s, TELOPT_LINEMODE); TFLAG_SET(TELOPT_LINEMODE, WILL);
- telnet_senddo(s, TELOPT_BINARY); TFLAG_SET(TELOPT_BINARY, DO);
- telnet_sendwill(s, TELOPT_BINARY); TFLAG_SET(TELOPT_BINARY, WILL);
+ write(netfd, G.iacbuf, G.iaclen);
+ G.iaclen = 0;
}
-static void telnet_suboptions(int net)
+#define write_str(fd, str) write(fd, str, sizeof(str) - 1)
+
+static void doexit(int ev) NORETURN;
+static void doexit(int ev)
{
- char buf[256];
- switch (SB_GET()) {
- case TELOPT_TTYPE:
- if (TFLAG_ISSET(TELOPT_TTYPE, WONT)) return;
- if (SB_EOF() || SB_GET() != TELQUAL_SEND) {
- return;
- } else {
- const char *name = getenv("TERM");
- if (name) {
- snprintf(buf, sizeof(buf), "%c%c%c%c%s%c%c", IAC, SB,
- TELOPT_TTYPE, TELQUAL_IS, name, IAC, SE);
- write(net, buf, strlen(name)+6);
- }
- }
- break;
- case TELOPT_TSPEED:
- if (TFLAG_ISSET(TELOPT_TSPEED, WONT)) return;
- if (SB_EOF()) return;
- if (SB_GET() == TELQUAL_SEND) {
- /*
- long oospeed, iispeed;
- netoring.printf("%c%c%c%c%ld,%ld%c%c", IAC, SB, TELOPT_TSPEED,
- TELQUAL_IS, oospeed, iispeed, IAC, SE);
- */
+ cookmode();
+ exit(ev);
+}
+
+static void con_escape(void)
+{
+ char b;
+
+ if (bb_got_signal) /* came from line mode... go raw */
+ rawmode();
+
+ write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
+ " l go to line mode\r\n"
+ " c go to character mode\r\n"
+ " z suspend telnet\r\n"
+ " e exit telnet\r\n");
+
+ if (read(STDIN_FILENO, &b, 1) <= 0)
+ doexit(EXIT_FAILURE);
+
+ switch (b) {
+ case 'l':
+ if (!bb_got_signal) {
+ do_linemode();
+ goto ret;
+ }
+ break;
+ case 'c':
+ if (bb_got_signal) {
+ will_charmode();
+ goto ret;
+ }
+ break;
+ case 'z':
+ cookmode();
+ kill(0, SIGTSTP);
+ rawmode();
+ break;
+ case 'e':
+ doexit(EXIT_SUCCESS);
+ }
+
+ write_str(1, "continuing...\r\n");
+
+ if (bb_got_signal)
+ cookmode();
+ ret:
+ bb_got_signal = 0;
+}
+
+static void handle_net_output(int len)
+{
+ /* here we could do smart tricks how to handle 0xFF:s in output
+ * stream like writing twice every sequence of FF:s (thus doing
+ * many write()s. But I think interactive telnet application does
+ * not need to be 100% 8-bit clean, so changing every 0xff:s to
+ * 0x7f:s
+ *
+ * 2002-mar-21, Przemyslaw Czerpak (druzus@polbox.com)
+ * I don't agree.
+ * first - I cannot use programs like sz/rz
+ * second - the 0x0D is sent as one character and if the next
+ * char is 0x0A then it's eaten by a server side.
+ * third - why do you have to make 'many write()s'?
+ * I don't understand.
+ * So I implemented it. It's really useful for me. I hope that
+ * other people will find it interesting too.
+ */
+ byte outbuf[2 * DATABUFSIZE];
+ byte *p = (byte*)G.buf;
+ int j = 0;
+
+ for (; len > 0; len--, p++) {
+ byte c = *p;
+ if (c == 0x1d) {
+ con_escape();
+ return;
+ }
+ outbuf[j++] = c;
+ if (c == IAC)
+ outbuf[j++] = c; /* IAC -> IAC IAC */
+ else if (c == '\r')
+ outbuf[j++] = '\0'; /* CR -> CR NUL */
+ }
+ if (j > 0)
+ full_write(netfd, outbuf, j);
+}
+
+static void handle_net_input(int len)
+{
+ int i;
+ int cstart = 0;
+
+ for (i = 0; i < len; i++) {
+ byte c = G.buf[i];
+
+ if (G.telstate == TS_NORMAL) { /* most typical state */
+ if (c == IAC) {
+ cstart = i;
+ G.telstate = TS_IAC;
}
- break;
- /*
- case TELOPT_LFLOW:
- if (TFLAG_ISSET(TELOPT_LFLOW, WONT)) return;
- if (SB_EOF()) return;
- switch(SB_GET()) {
- case 1: localflow = 1; break;
- case 0: localflow = 0; break;
- default: return;
+ else if (c == '\r') {
+ cstart = i + 1;
+ G.telstate = TS_CR;
}
- break;
- case TELOPT_LINEMODE:
- if (TFLAG_ISSET(TELOPT_LINEMODE, WONT)) return;
- if (SB_EOF()) return;
- switch (SB_GET()) {
- case WILL: lm_will(subpointer, SB_LEN()); break;
- case WONT: lm_wont(subpointer, SB_LEN()); break;
- case DO: lm_do(subpointer, SB_LEN()); break;
- case DONT: lm_dont(subpointer, SB_LEN()); break;
- case LM_SLC: slc(subpointer, SB_LEN()); break;
- case LM_MODE: lm_mode(subpointer, SB_LEN(), 0); break;
- default: break;
+ /* No IACs were seen so far, no need to copy
+ * bytes within G.buf: */
+ continue;
+ }
+
+ switch (G.telstate) {
+ case TS_CR:
+ /* Prev char was CR. If cur one is NUL, ignore it.
+ * See RFC 1123 section 3.3.1 for discussion of telnet EOL handling.
+ */
+ G.telstate = TS_COPY;
+ if (c == '\0')
+ break;
+ /* else: fall through - need to handle CR IAC ... properly */
+
+ case TS_COPY: /* Prev char was ordinary */
+ /* Similar to NORMAL, but in TS_COPY we need to copy bytes */
+ if (c == IAC)
+ G.telstate = TS_IAC;
+ else
+ G.buf[cstart++] = c;
+ if (c == '\r')
+ G.telstate = TS_CR;
+ break;
+
+ case TS_IAC: /* Prev char was IAC */
+ if (c == IAC) { /* IAC IAC -> one IAC */
+ G.buf[cstart++] = c;
+ G.telstate = TS_COPY;
+ break;
}
- break;
- case TELOPT_ENVIRON:
- if (SB_EOF()) return;
- switch(SB_PEEK()) {
- case TELQUAL_IS:
- case TELQUAL_INFO:
- if (TFLAG_ISSET(TELOPT_ENVIRON, DONT)) return;
- break;
- case TELQUAL_SEND:
- if (TFLAG_ISSET(TELOPT_ENVIRON, WONT)) return;
- break;
- default:
- return;
+ /* else */
+ switch (c) {
+ case SB:
+ G.telstate = TS_SUB1;
+ break;
+ case DO:
+ case DONT:
+ case WILL:
+ case WONT:
+ G.telwish = c;
+ G.telstate = TS_OPT;
+ break;
+ /* DATA MARK must be added later */
+ default:
+ G.telstate = TS_COPY;
}
- env_opt(subpointer, SB_LEN());
break;
- */
- case TELOPT_XDISPLOC:
- if (TFLAG_ISSET(TELOPT_XDISPLOC, WONT)) return;
- if (SB_EOF()) return;
- if (SB_GET() == TELQUAL_SEND) {
- const char *dp = getenv("DISPLAY");
- if (dp) {
- snprintf(buf, sizeof(buf), "%c%c%c%c%s%c%c", IAC, SB,
- TELOPT_XDISPLOC, TELQUAL_IS, dp, IAC, SE);
- write(net, buf, strlen(dp)+6);
- }
- }
- break;
- default:
+
+ case TS_OPT: /* Prev chars were IAC WILL/WONT/DO/DONT */
+ telopt(c);
+ G.telstate = TS_COPY;
+ break;
+
+ case TS_SUB1: /* Subnegotiation */
+ case TS_SUB2: /* Subnegotiation */
+ subneg(c); /* can change G.telstate */
break;
+ }
}
+
+ if (G.telstate != TS_NORMAL) {
+ /* We had some IACs, or CR */
+ if (G.iaclen)
+ iac_flush();
+ if (G.telstate == TS_COPY) /* we aren't in the middle of IAC */
+ G.telstate = TS_NORMAL;
+ len = cstart;
+ }
+
+ if (len)
+ full_write(STDOUT_FILENO, G.buf, len);
}
-static void sighandler(int sig)
+static void put_iac(int c)
{
- telnet_shutdown();
- exit(0);
+ G.iacbuf[G.iaclen++] = c;
}
-static int telnet_send(int tty, int net)
+static void put_iac2(byte wwdd, byte c)
{
- int ret;
- unsigned char ch;
-
- while ((ret = read(tty, &ch, 1)) > 0) {
- if (ch == 29) { /* 29 -- ctrl-] */
- /* do something here? */
- exit(0);
- } else {
- ret = write(net, &ch, 1);
- break;
- }
- }
- if (ret == -1 && errno == EWOULDBLOCK) return 1;
- return ret;
+ if (G.iaclen + 3 > IACBUFSIZE)
+ iac_flush();
+
+ put_iac(IAC);
+ put_iac(wwdd);
+ put_iac(c);
}
-static int telnet_recv(int net, int tty)
+#if ENABLE_FEATURE_TELNET_TTYPE
+static void put_iac_subopt(byte c, char *str)
{
- /* globals: tr_state - telnet receive state */
- int ret, c = 0;
- unsigned char ch;
-
- while ((ret = read(net, &ch, 1)) > 0) {
- c = ch;
- /* printf("%02X ", c); fflush(stdout); */
- switch (tr_state) {
- case TS_DATA:
- if (c == IAC) {
- tr_state = TS_IAC;
- break;
- } else {
- write(tty, &c, 1);
- }
- break;
- case TS_IAC:
- switch (c) {
- case WILL:
- tr_state = TS_WILL; break;
- case WONT:
- tr_state = TS_WONT; break;
- case DO:
- tr_state = TS_DO; break;
- case DONT:
- tr_state = TS_DONT; break;
- case SB:
- SB_CLEAR();
- tr_state = TS_SB; break;
- case IAC:
- write(tty, &c, 1); /* fallthrough */
- default:
- tr_state = TS_DATA;
- }
-
- /* subnegotiation -- ignored for now */
- case TS_SB:
- if (c == IAC) tr_state = TS_SE;
- else SB_ACCUM(c);
- break;
- case TS_SE:
- if (c == IAC) {
- SB_ACCUM(IAC);
- tr_state = TS_SB;
- } else if (c == SE) {
- SB_ACCUM(IAC);
- SB_ACCUM(SE);
- subpointer -= 2;
- SB_TERM();
- telnet_suboptions(net);
- tr_state = TS_DATA;
- }
- /* otherwise this is an error, but we ignore it for now */
- break;
- /* handle incoming requests */
- case TS_WILL:
- printf("WILL %s\n", telopts[c]);
- if (!TFLAG_ISSET(c, DO)) {
- if (c == TELOPT_BINARY) {
- TFLAG_SET(c, DO);
- TFLAG_CLR(c, DONT);
- telnet_senddo(net, c);
- } else {
- TFLAG_SET(c, DONT);
- telnet_senddont(net, c);
- }
- }
- telnet_senddont(net, c);
- tr_state = TS_DATA;
- break;
- case TS_WONT:
- printf("WONT %s\n", telopts[c]);
- if (!TFLAG_ISSET(c, DONT)) {
- TFLAG_SET(c, DONT);
- TFLAG_CLR(c, DO);
- telnet_senddont(net, c);
- }
- tr_state = TS_DATA;
- break;
- case TS_DO:
- printf("DO %s\n", telopts[c]);
- if (!TFLAG_ISSET(c, WILL)) {
- if (c == TELOPT_BINARY) {
- TFLAG_SET(c, WILL);
- TFLAG_CLR(c, WONT);
- telnet_sendwill(net, c);
- } else {
- TFLAG_SET(c, WONT);
- telnet_sendwont(net, c);
- }
- }
- tr_state = TS_DATA;
- break;
- case TS_DONT:
- printf("DONT %s\n", telopts[c]);
- if (!TFLAG_ISSET(c, WONT)) {
- TFLAG_SET(c, WONT);
- TFLAG_CLR(c, WILL);
- telnet_sendwont(net, c);
- }
- tr_state = TS_DATA;
- break;
+ int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )
+
+ if (G.iaclen + len > IACBUFSIZE)
+ iac_flush();
+
+ put_iac(IAC);
+ put_iac(SB);
+ put_iac(c);
+ put_iac(0);
+
+ while (*str)
+ put_iac(*str++);
+
+ put_iac(IAC);
+ put_iac(SE);
+}
+#endif
+
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+static void put_iac_subopt_autologin(void)
+{
+ int len = strlen(G.autologin) + 6; // (2 + 1 + 1 + strlen + 2)
+ const char *p = "USER";
+
+ if (G.iaclen + len > IACBUFSIZE)
+ iac_flush();
+
+ put_iac(IAC);
+ put_iac(SB);
+ put_iac(TELOPT_NEW_ENVIRON);
+ put_iac(TELQUAL_IS);
+ put_iac(NEW_ENV_VAR);
+
+ while (*p)
+ put_iac(*p++);
+
+ put_iac(NEW_ENV_VALUE);
+
+ p = G.autologin;
+ while (*p)
+ put_iac(*p++);
+
+ put_iac(IAC);
+ put_iac(SE);
+}
+#endif
+
+#if ENABLE_FEATURE_AUTOWIDTH
+static void put_iac_naws(byte c, int x, int y)
+{
+ if (G.iaclen + 9 > IACBUFSIZE)
+ iac_flush();
+
+ put_iac(IAC);
+ put_iac(SB);
+ put_iac(c);
+
+ put_iac((x >> 8) & 0xff);
+ put_iac(x & 0xff);
+ put_iac((y >> 8) & 0xff);
+ put_iac(y & 0xff);
+
+ put_iac(IAC);
+ put_iac(SE);
+}
+#endif
+
+static char const escapecharis[] ALIGN1 = "\r\nEscape character is ";
+
+static void setConMode(void)
+{
+ if (G.telflags & UF_ECHO) {
+ if (G.charmode == CHM_TRY) {
+ G.charmode = CHM_ON;
+ printf("\r\nEntering character mode%s'^]'.\r\n", escapecharis);
+ rawmode();
+ }
+ } else {
+ if (G.charmode != CHM_OFF) {
+ G.charmode = CHM_OFF;
+ printf("\r\nEntering line mode%s'^C'.\r\n", escapecharis);
+ cookmode();
}
-
}
- if (ret == -1 && errno == EWOULDBLOCK) return 1;
- return ret;
}
-/* ******************************************************************* */
-static void telnet_init(void)
+static void will_charmode(void)
+{
+ G.charmode = CHM_TRY;
+ G.telflags |= (UF_ECHO | UF_SGA);
+ setConMode();
+
+ put_iac2(DO, TELOPT_ECHO);
+ put_iac2(DO, TELOPT_SGA);
+ iac_flush();
+}
+
+static void do_linemode(void)
{
- struct termios tmp_tc;
- cc_t esc = (']' & 0x1f); /* ctrl-] */
-
- memset(options, 0, sizeof(options));
- SB_CLEAR();
-
- tcgetattr(STDIN, &saved_tc);
-
- tmp_tc = saved_tc;
- tmp_tc.c_lflag &= ~ECHO; /* echo */
- tmp_tc.c_oflag |= ONLCR; /* NL->CRLF translation */
- tmp_tc.c_iflag |= ICRNL;
- tmp_tc.c_iflag &= ~(IXANY|IXOFF|IXON); /* no flow control */
- tmp_tc.c_lflag |= ISIG; /* trap signals */
- tmp_tc.c_lflag &= ~ICANON; /* edit mode */
-
- /* misc settings, compat with default telnet stuff */
- tmp_tc.c_oflag &= ~TABDLY;
-
- /* 8-bit clean */
- tmp_tc.c_iflag &= ~ISTRIP;
- tmp_tc.c_cflag &= ~(CSIZE|PARENB);
- tmp_tc.c_cflag |= saved_tc.c_cflag & (CSIZE|PARENB);
- tmp_tc.c_oflag |= OPOST;
-
- /* set escape character */
- tmp_tc.c_cc[VEOL] = esc;
- tcsetattr(STDIN, TCSADRAIN, &tmp_tc);
+ G.charmode = CHM_TRY;
+ G.telflags &= ~(UF_ECHO | UF_SGA);
+ setConMode();
+
+ put_iac2(DONT, TELOPT_ECHO);
+ put_iac2(DONT, TELOPT_SGA);
+ iac_flush();
}
-static void telnet_start(char *hostname, int port)
+static void to_notsup(char c)
{
- struct hostent *host = 0;
- struct sockaddr_in addr;
- int s, c;
- fd_set rfds, wfds;
-
- memset(&addr, 0, sizeof(addr));
- host = gethostbyname(hostname);
- if (!host) {
- fprintf(stderr, "Unknown host: %s\n", hostname);
+ if (G.telwish == WILL)
+ put_iac2(DONT, c);
+ else if (G.telwish == DO)
+ put_iac2(WONT, c);
+}
+
+static void to_echo(void)
+{
+ /* if server requests ECHO, don't agree */
+ if (G.telwish == DO) {
+ put_iac2(WONT, TELOPT_ECHO);
return;
}
- addr.sin_family = host->h_addrtype;
- memcpy(&addr.sin_addr, host->h_addr, sizeof(addr.sin_addr));
- addr.sin_port = htons(port);
-
- printf("Trying %s...\n", inet_ntoa(addr.sin_addr));
-
- if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) PERROR("socket");
- if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) < 0)
- PERROR("connect");
- printf("Connected to %s\n", hostname);
- printf("Escape character is ^]\n");
-
- signal(SIGINT, sighandler);
- signal(SIGQUIT, sighandler);
- signal(SIGPIPE, sighandler);
- signal(SIGWINCH, sighandler);
-
- /* make inputs nonblocking */
- c = 1;
- ioctl(s, FIONBIO, &c);
- ioctl(STDIN, FIONBIO, &c);
-
- if (port == TELNETPORT) telnet_setoptions(s);
-
- /* shuttle data back and forth between tty and socket */
- while (1) {
- FD_ZERO(&rfds);
- FD_ZERO(&wfds);
-
- FD_SET(s, &rfds);
- /* FD_SET(s, &wfds); */
- FD_SET(STDIN, &rfds);
- /* FD_SET(STDOUT, &wfds); */
-
- if ((c = select(s+1, &rfds, &wfds, 0, 0))) {
- if (c == -1) {
- /* handle errors */
- PERROR("select");
- }
- if (FD_ISSET(s, &rfds)) {
- /* input from network */
- FD_CLR(s, &rfds);
- c = telnet_recv(s, STDOUT);
- if (c == 0) break;
- if (c < 0) PERROR("telnet_recv");
- }
- if (FD_ISSET(STDIN, &rfds)) {
- /* input from tty */
- FD_CLR(STDIN, &rfds);
- c = telnet_send(STDIN, s);
- if (c == 0) break;
- if (c < 0) PERROR("telnet_send");
- }
+ if (G.telwish == DONT)
+ return;
+
+ if (G.telflags & UF_ECHO) {
+ if (G.telwish == WILL)
+ return;
+ } else if (G.telwish == WONT)
+ return;
+
+ if (G.charmode != CHM_OFF)
+ G.telflags ^= UF_ECHO;
+
+ if (G.telflags & UF_ECHO)
+ put_iac2(DO, TELOPT_ECHO);
+ else
+ put_iac2(DONT, TELOPT_ECHO);
+
+ setConMode();
+ full_write1_str("\r\n"); /* sudden modec */
+}
+
+static void to_sga(void)
+{
+ /* daemon always sends will/wont, client do/dont */
+
+ if (G.telflags & UF_SGA) {
+ if (G.telwish == WILL)
+ return;
+ } else if (G.telwish == WONT)
+ return;
+
+ G.telflags ^= UF_SGA; /* toggle */
+ if (G.telflags & UF_SGA)
+ put_iac2(DO, TELOPT_SGA);
+ else
+ put_iac2(DONT, TELOPT_SGA);
+}
+
+#if ENABLE_FEATURE_TELNET_TTYPE
+static void to_ttype(void)
+{
+ /* Tell server we will (or won't) do TTYPE */
+ if (G.ttype)
+ put_iac2(WILL, TELOPT_TTYPE);
+ else
+ put_iac2(WONT, TELOPT_TTYPE);
+}
+#endif
+
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+static void to_new_environ(void)
+{
+ /* Tell server we will (or will not) do AUTOLOGIN */
+ if (G.autologin)
+ put_iac2(WILL, TELOPT_NEW_ENVIRON);
+ else
+ put_iac2(WONT, TELOPT_NEW_ENVIRON);
+}
+#endif
+
+#if ENABLE_FEATURE_AUTOWIDTH
+static void to_naws(void)
+{
+ /* Tell server we will do NAWS */
+ put_iac2(WILL, TELOPT_NAWS);
+}
+#endif
+
+static void telopt(byte c)
+{
+ switch (c) {
+ case TELOPT_ECHO:
+ to_echo(); break;
+ case TELOPT_SGA:
+ to_sga(); break;
+#if ENABLE_FEATURE_TELNET_TTYPE
+ case TELOPT_TTYPE:
+ to_ttype(); break;
+#endif
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+ case TELOPT_NEW_ENVIRON:
+ to_new_environ(); break;
+#endif
+#if ENABLE_FEATURE_AUTOWIDTH
+ case TELOPT_NAWS:
+ to_naws();
+ put_iac_naws(c, G.win_width, G.win_height);
+ break;
+#endif
+ default:
+ to_notsup(c);
+ break;
+ }
+}
+
+/* subnegotiation -- ignore all (except TTYPE,NAWS) */
+static void subneg(byte c)
+{
+ switch (G.telstate) {
+ case TS_SUB1:
+ if (c == IAC)
+ G.telstate = TS_SUB2;
+#if ENABLE_FEATURE_TELNET_TTYPE
+ else
+ if (c == TELOPT_TTYPE && G.ttype)
+ put_iac_subopt(TELOPT_TTYPE, G.ttype);
+#endif
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+ else
+ if (c == TELOPT_NEW_ENVIRON && G.autologin)
+ put_iac_subopt_autologin();
+#endif
+ break;
+ case TS_SUB2:
+ if (c == SE) {
+ G.telstate = TS_COPY;
+ return;
}
+ G.telstate = TS_SUB1;
+ break;
}
-
- return;
}
-static void telnet_shutdown(void)
+static void rawmode(void)
{
- printf("\n");
- tcsetattr(STDIN, TCSANOW, &saved_tc);
+ if (G.do_termios)
+ tcsetattr(0, TCSADRAIN, &G.termios_raw);
}
-#ifdef STANDALONE_TELNET
-void usage(const char *msg)
+static void cookmode(void)
{
- printf("%s", msg);
- exit(0);
+ if (G.do_termios)
+ tcsetattr(0, TCSADRAIN, &G.termios_def);
}
-int main(int argc, char **argv)
+int telnet_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int telnet_main(int argc UNUSED_PARAM, char **argv)
+{
+ char *host;
+ int port;
+ int len;
+ struct pollfd ufds[2];
+
+ INIT_G();
+
+#if ENABLE_FEATURE_AUTOWIDTH
+ get_terminal_width_height(0, &G.win_width, &G.win_height);
+#endif
+
+#if ENABLE_FEATURE_TELNET_TTYPE
+ G.ttype = getenv("TERM");
+#endif
+
+ if (tcgetattr(0, &G.termios_def) >= 0) {
+ G.do_termios = 1;
+ G.termios_raw = G.termios_def;
+ cfmakeraw(&G.termios_raw);
+ }
+
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+ if (1 & getopt32(argv, "al:", &G.autologin))
+ G.autologin = getenv("USER");
+ argv += optind;
#else
-int telnet_main(int argc, char **argv)
+ argv++;
#endif
-{
- int port = TELNETPORT;
-
- argc--; argv++;
- if (argc < 1) usage(telnet_usage);
- if (argc > 1) port = atoi(argv[1]);
- telnet_init();
- atexit(telnet_shutdown);
-
- telnet_start(argv[0], port);
- return 0;
-}
+ if (!*argv)
+ bb_show_usage();
+ host = *argv++;
+ port = bb_lookup_port(*argv ? *argv++ : "telnet", "tcp", 23);
+ if (*argv) /* extra params?? */
+ bb_show_usage();
-/*
- * Copyright (c) 1988, 1990 Regents of the University of California.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
+ xmove_fd(create_and_connect_stream_or_die(host, port), netfd);
+
+ setsockopt(netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
+
+ signal(SIGINT, record_signo);
+
+ ufds[0].fd = STDIN_FILENO;
+ ufds[0].events = POLLIN;
+ ufds[1].fd = netfd;
+ ufds[1].events = POLLIN;
+
+ while (1) {
+ if (poll(ufds, 2, -1) < 0) {
+ /* error, ignore and/or log something, bay go to loop */
+ if (bb_got_signal)
+ con_escape();
+ else
+ sleep(1);
+ continue;
+ }
+
+// FIXME: reads can block. Need full bidirectional buffering.
+
+ if (ufds[0].revents) {
+ len = safe_read(STDIN_FILENO, G.buf, DATABUFSIZE);
+ if (len <= 0)
+ doexit(EXIT_SUCCESS);
+ TRACE(0, ("Read con: %d\n", len));
+ handle_net_output(len);
+ }
+
+ if (ufds[1].revents) {
+ len = safe_read(netfd, G.buf, DATABUFSIZE);
+ if (len <= 0) {
+ full_write1_str("Connection closed by foreign host\r\n");
+ doexit(EXIT_FAILURE);
+ }
+ TRACE(0, ("Read netfd (%d): %d\n", netfd, len));
+ handle_net_input(len);
+ }
+ } /* while (1) */
+}
projects / oweals / busybox.git / blobdiff