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authorErik Andersen2000-02-22 17:17:45 +0000
committerErik Andersen2000-02-22 17:17:45 +0000
commitf7c49ef2d106eb38f648432e2cff2a81bb982437 (patch)
tree0860a3b7a85d769aa440eba43cf35e0560d153c6 /networking
parent3b9522f2af942c92eec638995268cccddd82c4f8 (diff)
downloadbusybox-f7c49ef2d106eb38f648432e2cff2a81bb982437.zip
busybox-f7c49ef2d106eb38f648432e2cff2a81bb982437.tar.gz
Sync up a few things. Add in a new telnet implementation (still
not perfect though). -Erik
Diffstat (limited to 'networking')
-rw-r--r--networking/telnet.c503
1 files changed, 503 insertions, 0 deletions
diff --git a/networking/telnet.c b/networking/telnet.c
new file mode 100644
index 0000000..076728f
--- /dev/null
+++ b/networking/telnet.c
@@ -0,0 +1,503 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * $Id: telnet.c,v 1.1 2000/02/22 17:17:45 erik Exp $
+ * Mini telnet implementation for busybox
+ *
+ * Copyright (C) 2000 by Randolph Chung <tausq@debian.org>
+ *
+ * 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
+ *
+ * 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
+#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\n";
+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)
+{
+ /*
+ telnet_senddo(s, TELOPT_SGA); TFLAG_SET(TELOPT_SGA, DO);
+ telnet_sendwill(s, TELOPT_NAWS); TFLAG_SET(TELOPT_NAWS, WILL);
+ telnet_sendwill(s, TELOPT_TSPEED); TFLAG_SET(TELOPT_TSPEED, WILL);
+ telnet_sendwill(s, TELOPT_LFLOW); TFLAG_SET(TELOPT_LFLOW, WILL);
+ telnet_sendwill(s, TELOPT_LINEMODE); TFLAG_SET(TELOPT_LINEMODE, 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_BINARY); TFLAG_SET(TELOPT_BINARY, DO);
+ telnet_sendwill(s, TELOPT_BINARY); TFLAG_SET(TELOPT_BINARY, WILL);
+}
+
+static void telnet_suboptions(int net)
+{
+ 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);
+ */
+ }
+ 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;
+ }
+ 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;
+ }
+ 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;
+ }
+ 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:
+ break;
+ }
+}
+
+static void sighandler(int sig)
+{
+ telnet_shutdown();
+ exit(0);
+}
+
+static int telnet_send(int tty, int net)
+{
+ 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;
+}
+
+static int telnet_recv(int net, int tty)
+{
+ /* 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;
+ }
+
+ }
+ if (ret == -1 && errno == EWOULDBLOCK) return 1;
+ return ret;
+}
+
+/* ******************************************************************* */
+static void telnet_init(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);
+}
+
+static void telnet_start(char *hostname, int port)
+{
+ 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);
+ 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");
+ }
+ }
+ }
+
+ return;
+}
+
+static void telnet_shutdown(void)
+{
+ printf("\n");
+ tcsetattr(STDIN, TCSANOW, &saved_tc);
+}
+
+#ifdef STANDALONE_TELNET
+void usage(const char *msg)
+{
+ printf("%s", msg);
+ exit(0);
+}
+
+int main(int argc, char **argv)
+#else
+int telnet_main(int argc, char **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;
+}
+
+/*
+ * 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.
+ */