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-rw-r--r--telnet.c711
1 files changed, 0 insertions, 711 deletions
diff --git a/telnet.c b/telnet.c
deleted file mode 100644
index ce82a0e..0000000
--- a/telnet.c
+++ /dev/null
@@ -1,711 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * telnet implementation for busybox
- *
- * Author: Tomi Ollila <too@iki.fi>
- * Copyright (C) 1994-2000 by Tomi Ollila
- *
- * Created: Thu Apr 7 13:29:41 1994 too
- * Last modified: Fri Jun 9 14:34:24 2000 too
- *
- * 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.
- *
- * 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.
- *
- * 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@lineo.com>
- * Modified 2001/05/07 to add ability to pass TTYPE to remote host by Jim McQuillan
- * <jam@ltsp.org>
- *
- */
-
-#include <termios.h>
-#include <unistd.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <signal.h>
-#include <arpa/telnet.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <netdb.h>
-#include "busybox.h"
-
-#if 0
-static const int DOTRACE = 1;
-#endif
-
-#ifdef DOTRACE
-#include <arpa/inet.h> /* for inet_ntoa()... */
-#define TRACE(x, y) do { if (x) printf y; } while (0)
-#else
-#define TRACE(x, y)
-#endif
-
-#if 0
-#define USE_POLL
-#include <sys/poll.h>
-#else
-#include <sys/time.h>
-#endif
-
-#define DATABUFSIZE 128
-#define IACBUFSIZE 128
-
-static const int CHM_TRY = 0;
-static const int CHM_ON = 1;
-static const int CHM_OFF = 2;
-
-static const int UF_ECHO = 0x01;
-static const int UF_SGA = 0x02;
-
-enum {
- TS_0 = 1,
- TS_IAC = 2,
- TS_OPT = 3,
- TS_SUB1 = 4,
- TS_SUB2 = 5,
-};
-
-#define WriteCS(fd, str) write(fd, str, sizeof str -1)
-
-typedef unsigned char byte;
-
-/* use globals to reduce size ??? */ /* test this hypothesis later */
-static struct Globalvars {
- int netfd; /* console fd:s are 0 and 1 (and 2) */
- /* same buffer used both for network and console read/write */
- char buf[DATABUFSIZE]; /* allocating so static size is smaller */
- byte telstate; /* telnet negotiation state from network input */
- byte telwish; /* DO, DONT, WILL, WONT */
- byte charmode;
- byte telflags;
- byte gotsig;
- /* buffer to handle telnet negotiations */
- char iacbuf[IACBUFSIZE];
- short iaclen; /* could even use byte */
- struct termios termios_def;
- struct termios termios_raw;
-} G;
-
-#define xUSE_GLOBALVAR_PTR /* xUSE... -> don't use :D (makes smaller code) */
-
-#ifdef USE_GLOBALVAR_PTR
-struct Globalvars * Gptr;
-#define G (*Gptr)
-#else
-static struct Globalvars G;
-#endif
-
-static inline void iacflush()
-{
- write(G.netfd, G.iacbuf, G.iaclen);
- G.iaclen = 0;
-}
-
-/* Function prototypes */
-static int getport(char * p);
-static struct in_addr getserver(char * p);
-static int create_socket();
-static void setup_sockaddr_in(struct sockaddr_in * addr, int port);
-static int remote_connect(struct in_addr addr, int port);
-static void rawmode();
-static void cookmode();
-static void do_linemode();
-static void will_charmode();
-static void telopt(byte c);
-static int subneg(byte c);
-#if 0
-static int local_bind(int port);
-#endif
-
-/* Some globals */
-static int one = 1;
-
-#ifdef BB_FEATURE_TELNET_TTYPE
-static char *ttype;
-#endif
-
-static void doexit(int ev)
-{
- cookmode();
- exit(ev);
-}
-
-static void conescape()
-{
- char b;
-
- if (G.gotsig) /* came from line mode... go raw */
- rawmode();
-
- WriteCS(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(0, &b, 1) <= 0)
- doexit(1);
-
- switch (b)
- {
- case 'l':
- if (!G.gotsig)
- {
- do_linemode();
- goto rrturn;
- }
- break;
- case 'c':
- if (G.gotsig)
- {
- will_charmode();
- goto rrturn;
- }
- break;
- case 'z':
- cookmode();
- kill(0, SIGTSTP);
- rawmode();
- break;
- case 'e':
- doexit(0);
- }
-
- WriteCS(1, "continuing...\r\n");
-
- if (G.gotsig)
- cookmode();
-
- rrturn:
- G.gotsig = 0;
-
-}
-static void handlenetoutput(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 */
-
- int i;
- byte * p = G.buf;
-
- for (i = len; i > 0; i--, p++)
- {
- if (*p == 0x1d)
- {
- conescape();
- return;
- }
- if (*p == 0xff)
- *p = 0x7f;
- }
- write(G.netfd, G.buf, len);
-}
-
-
-static void handlenetinput(int len)
-{
- int i;
- int cstart = 0;
-
- for (i = 0; i < len; i++)
- {
- byte c = G.buf[i];
-
- if (G.telstate == 0) /* most of the time state == 0 */
- {
- if (c == IAC)
- {
- cstart = i;
- G.telstate = TS_IAC;
- }
- }
- else
- switch (G.telstate)
- {
- case TS_0:
- if (c == IAC)
- G.telstate = TS_IAC;
- else
- G.buf[cstart++] = c;
- break;
-
- case TS_IAC:
- if (c == IAC) /* IAC IAC -> 0xFF */
- {
- G.buf[cstart++] = c;
- G.telstate = TS_0;
- break;
- }
- /* 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;
- default:
- G.telstate = TS_0; /* DATA MARK must be added later */
- }
- break;
- case TS_OPT: /* WILL, WONT, DO, DONT */
- telopt(c);
- G.telstate = TS_0;
- break;
- case TS_SUB1: /* Subnegotiation */
- case TS_SUB2: /* Subnegotiation */
- if (subneg(c) == TRUE)
- G.telstate = TS_0;
- break;
- }
- }
- if (G.telstate)
- {
- if (G.iaclen) iacflush();
- if (G.telstate == TS_0) G.telstate = 0;
-
- len = cstart;
- }
-
- if (len)
- write(1, G.buf, len);
-}
-
-
-/* ******************************* */
-
-static inline void putiac(int c)
-{
- G.iacbuf[G.iaclen++] = c;
-}
-
-
-static void putiac2(byte wwdd, byte c)
-{
- if (G.iaclen + 3 > IACBUFSIZE)
- iacflush();
-
- putiac(IAC);
- putiac(wwdd);
- putiac(c);
-}
-
-#if 0
-static void putiac1(byte c)
-{
- if (G.iaclen + 2 > IACBUFSIZE)
- iacflush();
-
- putiac(IAC);
- putiac(c);
-}
-#endif
-
-#ifdef BB_FEATURE_TELNET_TTYPE
-static void putiac_subopt(byte c, char *str)
-{
- int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )
-
- if (G.iaclen + len > IACBUFSIZE)
- iacflush();
-
- putiac(IAC);
- putiac(SB);
- putiac(c);
- putiac(0);
-
- while(*str)
- putiac(*str++);
-
- putiac(IAC);
- putiac(SE);
-}
-#endif
-
-/* void putiacstring (subneg strings) */
-
-/* ******************************* */
-
-static char const escapecharis[] = "\r\nEscape character is ";
-
-static void setConMode()
-{
- 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();
- }
- }
-}
-
-/* ******************************* */
-
-static void will_charmode()
-{
- G.charmode = CHM_TRY;
- G.telflags |= (UF_ECHO | UF_SGA);
- setConMode();
-
- putiac2(DO, TELOPT_ECHO);
- putiac2(DO, TELOPT_SGA);
- iacflush();
-}
-
-static void do_linemode()
-{
- G.charmode = CHM_TRY;
- G.telflags &= ~(UF_ECHO | UF_SGA);
- setConMode();
-
- putiac2(DONT, TELOPT_ECHO);
- putiac2(DONT, TELOPT_SGA);
- iacflush();
-}
-
-/* ******************************* */
-
-static inline void to_notsup(char c)
-{
- if (G.telwish == WILL) putiac2(DONT, c);
- else if (G.telwish == DO) putiac2(WONT, c);
-}
-
-static inline void to_echo()
-{
- /* if server requests ECHO, don't agree */
- if (G.telwish == DO) { putiac2(WONT, TELOPT_ECHO); return; }
- else 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)
- putiac2(DO, TELOPT_ECHO);
- else
- putiac2(DONT, TELOPT_ECHO);
-
- setConMode();
- WriteCS(1, "\r\n"); /* sudden modec */
-}
-
-static inline void to_sga()
-{
- /* daemon always sends will/wont, client do/dont */
-
- if (G.telflags & UF_SGA)
- {
- if (G.telwish == WILL)
- return;
- }
- else
- if (G.telwish == WONT)
- return;
-
- if ((G.telflags ^= UF_SGA) & UF_SGA) /* toggle */
- putiac2(DO, TELOPT_SGA);
- else
- putiac2(DONT, TELOPT_SGA);
-
- return;
-}
-
-#ifdef BB_FEATURE_TELNET_TTYPE
-static inline void to_ttype()
-{
- /* Tell server we will (or won't) do TTYPE */
-
- if(ttype)
- putiac2(WILL, TELOPT_TTYPE);
- else
- putiac2(WONT, TELOPT_TTYPE);
-
- return;
-}
-#endif
-
-static void telopt(byte c)
-{
- switch (c)
- {
- case TELOPT_ECHO: to_echo(c); break;
- case TELOPT_SGA: to_sga(c); break;
-#ifdef BB_FEATURE_TELNET_TTYPE
- case TELOPT_TTYPE: to_ttype(c); break;
-#endif
- default: to_notsup(c); break;
- }
-}
-
-
-/* ******************************* */
-
-/* subnegotiation -- ignore all (except TTYPE) */
-
-static int subneg(byte c)
-{
- switch (G.telstate)
- {
- case TS_SUB1:
- if (c == IAC)
- G.telstate = TS_SUB2;
-#ifdef BB_FEATURE_TELNET_TTYPE
- else
- if (c == TELOPT_TTYPE)
- putiac_subopt(TELOPT_TTYPE,ttype);
-#endif
- break;
- case TS_SUB2:
- if (c == SE)
- return TRUE;
- G.telstate = TS_SUB1;
- /* break; */
- }
- return FALSE;
-}
-
-/* ******************************* */
-
-static void fgotsig(int sig)
-{
- G.gotsig = sig;
-}
-
-
-static void rawmode()
-{
- tcsetattr(0, TCSADRAIN, &G.termios_raw);
-}
-
-static void cookmode()
-{
- tcsetattr(0, TCSADRAIN, &G.termios_def);
-}
-
-extern int telnet_main(int argc, char** argv)
-{
- struct in_addr host;
- int port;
- int len;
-#ifdef USE_POLL
- struct pollfd ufds[2];
-#else
- fd_set readfds;
- int maxfd;
-#endif
-
-#ifdef BB_FEATURE_TELNET_TTYPE
- ttype = getenv("TERM");
-#endif
-
- memset(&G, 0, sizeof G);
-
- if (tcgetattr(0, &G.termios_def) < 0)
- exit(1);
-
- G.termios_raw = G.termios_def;
- cfmakeraw(&G.termios_raw);
-
- if (argc < 2) show_usage();
- port = (argc > 2)? getport(argv[2]): 23;
-
- host = getserver(argv[1]);
-
- G.netfd = remote_connect(host, port);
-
- signal(SIGINT, fgotsig);
-
-#ifdef USE_POLL
- ufds[0].fd = 0; ufds[1].fd = G.netfd;
- ufds[0].events = ufds[1].events = POLLIN;
-#else
- FD_ZERO(&readfds);
- FD_SET(0, &readfds);
- FD_SET(G.netfd, &readfds);
- maxfd = G.netfd + 1;
-#endif
-
- while (1)
- {
-#ifndef USE_POLL
- fd_set rfds = readfds;
-
- switch (select(maxfd, &rfds, NULL, NULL, NULL))
-#else
- switch (poll(ufds, 2, -1))
-#endif
- {
- case 0:
- /* timeout */
- case -1:
- /* error, ignore and/or log something, bay go to loop */
- if (G.gotsig)
- conescape();
- else
- sleep(1);
- break;
- default:
-
-#ifdef USE_POLL
- if (ufds[0].revents) /* well, should check POLLIN, but ... */
-#else
- if (FD_ISSET(0, &rfds))
-#endif
- {
- len = read(0, G.buf, DATABUFSIZE);
-
- if (len <= 0)
- doexit(0);
-
- TRACE(0, ("Read con: %d\n", len));
-
- handlenetoutput(len);
- }
-
-#ifdef USE_POLL
- if (ufds[1].revents) /* well, should check POLLIN, but ... */
-#else
- if (FD_ISSET(G.netfd, &rfds))
-#endif
- {
- len = read(G.netfd, G.buf, DATABUFSIZE);
-
- if (len <= 0)
- {
- WriteCS(1, "Connection closed by foreign host.\r\n");
- doexit(1);
- }
- TRACE(0, ("Read netfd (%d): %d\n", G.netfd, len));
-
- handlenetinput(len);
- }
- }
- }
-}
-
-static int getport(char * p)
-{
- unsigned int port = atoi(p);
-
- if ((unsigned)(port - 1 ) > 65534)
- {
- error_msg_and_die("%s: bad port number", p);
- }
- return port;
-}
-
-static struct in_addr getserver(char * host)
-{
- struct in_addr addr;
-
- struct hostent * he;
- he = xgethostbyname(host);
- memcpy(&addr, he->h_addr, sizeof addr);
-
- TRACE(1, ("addr: %s\n", inet_ntoa(addr)));
-
- return addr;
-}
-
-static int create_socket()
-{
- return socket(AF_INET, SOCK_STREAM, 0);
-}
-
-static void setup_sockaddr_in(struct sockaddr_in * addr, int port)
-{
- memset(addr, 0, sizeof(struct sockaddr_in));
- addr->sin_family = AF_INET;
- addr->sin_port = htons(port);
-}
-
-#if 0
-static int local_bind(int port)
-{
- struct sockaddr_in s_addr;
- int s = create_socket();
-
- setup_sockaddr_in(&s_addr, port);
-
- setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
-
- if (bind(s, &s_addr, sizeof s_addr) < 0)
- {
- char * e = sys_errlist[errno];
- syserrorexit("bind");
- exit(1);
- }
- listen(s, 1);
-
- return s;
-}
-#endif
-
-static int remote_connect(struct in_addr addr, int port)
-{
- struct sockaddr_in s_addr;
- int s = create_socket();
-
- setup_sockaddr_in(&s_addr, port);
- s_addr.sin_addr = addr;
-
- setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof one);
-
- if (connect(s, (struct sockaddr *)&s_addr, sizeof s_addr) < 0)
- {
- perror_msg_and_die("Unable to connect to remote host");
- }
- return s;
-}
-
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
-
generated by cgit v1.1 at 2024-12-27 21:39:28 +0000