2003-09-02 08:06:18 +05:30
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/* $Id: telnetd.c,v 1.7 2003/09/02 02:36:16 bug1 Exp $
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2002-10-01 02:22:10 +05:30
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*
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* Simple telnet server
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* Bjorn Wesen, Axis Communications AB (bjornw@axis.com)
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*
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* This file is distributed under the Gnu Public License (GPL),
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* please see the file LICENSE for further information.
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*
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* ---------------------------------------------------------------------------
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* (C) Copyright 2000, Axis Communications AB, LUND, SWEDEN
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****************************************************************************
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*
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* The telnetd manpage says it all:
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*
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* Telnetd operates by allocating a pseudo-terminal device (see pty(4)) for
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* a client, then creating a login process which has the slave side of the
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* pseudo-terminal as stdin, stdout, and stderr. Telnetd manipulates the
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* master side of the pseudo-terminal, implementing the telnet protocol and
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* passing characters between the remote client and the login process.
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*
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* Vladimir Oleynik <dzo@simtreas.ru> 2001
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* Set process group corrections, initial busybox port
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*/
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/*#define DEBUG 1 */
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#include <sys/time.h>
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#include <sys/socket.h>
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#include <sys/wait.h>
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#include <string.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <errno.h>
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#include <netinet/in.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <signal.h>
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#include <termios.h>
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#ifdef DEBUG
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#define TELCMDS
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#define TELOPTS
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#endif
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#include <arpa/telnet.h>
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#include <ctype.h>
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#include <sys/syslog.h>
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#include "busybox.h"
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#define BUFSIZE 4000
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2003-01-22 02:25:56 +05:30
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static const char *loginpath =
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#ifdef CONFIG_LOGIN
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"/bin/login";
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#else
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2003-09-02 08:06:18 +05:30
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DEFAULT_SHELL;
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2003-01-22 02:25:56 +05:30
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#endif
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static const char *issuefile = "/etc/issue.net";
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2002-10-01 02:22:10 +05:30
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/* shell name and arguments */
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static const char *argv_init[] = {NULL, NULL};
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/* structure that describes a session */
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struct tsession {
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2003-01-22 02:25:56 +05:30
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#ifdef CONFIG_FEATURE_TELNETD_INETD
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int sockfd_read, sockfd_write, ptyfd;
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#else /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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struct tsession *next;
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int sockfd, ptyfd;
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2003-01-22 02:25:56 +05:30
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#endif /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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int shell_pid;
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/* two circular buffers */
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char *buf1, *buf2;
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int rdidx1, wridx1, size1;
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int rdidx2, wridx2, size2;
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};
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/*
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This is how the buffers are used. The arrows indicate the movement
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of data.
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+-------+ wridx1++ +------+ rdidx1++ +----------+
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| | <-------------- | buf1 | <-------------- | |
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| | size1-- +------+ size1++ | |
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| pty | | socket |
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| | rdidx2++ +------+ wridx2++ | |
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| | --------------> | buf2 | --------------> | |
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+-------+ size2++ +------+ size2-- +----------+
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Each session has got two buffers.
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*/
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static int maxfd;
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static struct tsession *sessions;
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/*
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Remove all IAC's from the buffer pointed to by bf (recieved IACs are ignored
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and must be removed so as to not be interpreted by the terminal). Make an
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uninterrupted string of characters fit for the terminal. Do this by packing
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all characters meant for the terminal sequentially towards the end of bf.
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Return a pointer to the beginning of the characters meant for the terminal.
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and make *num_totty the number of characters that should be sent to
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the terminal.
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Note - If an IAC (3 byte quantity) starts before (bf + len) but extends
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past (bf + len) then that IAC will be left unprocessed and *processed will be
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less than len.
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FIXME - if we mean to send 0xFF to the terminal then it will be escaped,
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what is the escape character? We aren't handling that situation here.
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*/
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static char *
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remove_iacs(struct tsession *ts, int *pnum_totty) {
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unsigned char *ptr0 = ts->buf1 + ts->wridx1;
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unsigned char *ptr = ptr0;
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unsigned char *totty = ptr;
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unsigned char *end = ptr + MIN(BUFSIZE - ts->wridx1, ts->size1);
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int processed;
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int num_totty;
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while (ptr < end) {
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if (*ptr != IAC) {
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*totty++ = *ptr++;
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}
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else {
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if ((ptr+2) < end) {
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/* the entire IAC is contained in the buffer
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we were asked to process. */
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#ifdef DEBUG
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fprintf(stderr, "Ignoring IAC %s,%s\n",
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*ptr, TELCMD(*(ptr+1)), TELOPT(*(ptr+2)));
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#endif
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ptr += 3;
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} else {
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/* only the beginning of the IAC is in the
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buffer we were asked to process, we can't
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process this char. */
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break;
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}
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}
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}
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processed = ptr - ptr0;
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num_totty = totty - ptr0;
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/* the difference between processed and num_to tty
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is all the iacs we removed from the stream.
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Adjust buf1 accordingly. */
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ts->wridx1 += processed - num_totty;
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ts->size1 -= processed - num_totty;
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*pnum_totty = num_totty;
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/* move the chars meant for the terminal towards the end of the
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buffer. */
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return memmove(ptr - num_totty, ptr0, num_totty);
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}
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static int
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getpty(char *line)
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{
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int p;
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2002-11-11 03:56:19 +05:30
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#ifdef CONFIG_FEATURE_DEVPTS
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2002-10-01 02:22:10 +05:30
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p = open("/dev/ptmx", 2);
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if (p > 0) {
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grantpt(p);
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unlockpt(p);
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strcpy(line, ptsname(p));
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return(p);
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}
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#else
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struct stat stb;
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int i;
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int j;
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strcpy(line, "/dev/ptyXX");
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for (i = 0; i < 16; i++) {
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line[8] = "pqrstuvwxyzabcde"[i];
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line[9] = '0';
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if (stat(line, &stb) < 0) {
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continue;
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}
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for (j = 0; j < 16; j++) {
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line[9] = j < 10 ? j + '0' : j - 10 + 'a';
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if ((p = open(line, O_RDWR | O_NOCTTY)) >= 0) {
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line[5] = 't';
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return p;
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}
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}
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}
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2002-11-11 03:56:19 +05:30
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#endif /* CONFIG_FEATURE_DEVPTS */
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2002-10-01 02:22:10 +05:30
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return -1;
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}
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static void
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send_iac(struct tsession *ts, unsigned char command, int option)
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{
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/* We rely on that there is space in the buffer for now. */
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char *b = ts->buf2 + ts->rdidx2;
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*b++ = IAC;
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*b++ = command;
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*b++ = option;
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ts->rdidx2 += 3;
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ts->size2 += 3;
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}
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static struct tsession *
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2003-01-22 02:25:56 +05:30
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#ifdef CONFIG_FEATURE_TELNETD_INETD
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make_new_session(void)
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#else /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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make_new_session(int sockfd)
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2003-01-22 02:25:56 +05:30
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#endif /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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{
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struct termios termbuf;
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int pty, pid;
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char tty_name[32];
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struct tsession *ts = malloc(sizeof(struct tsession) + BUFSIZE * 2);
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ts->buf1 = (char *)(&ts[1]);
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ts->buf2 = ts->buf1 + BUFSIZE;
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2003-01-22 02:25:56 +05:30
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#ifdef CONFIG_FEATURE_TELNETD_INETD
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ts->sockfd_read = 0;
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ts->sockfd_write = 1;
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#else /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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ts->sockfd = sockfd;
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2003-01-22 02:25:56 +05:30
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#endif /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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ts->rdidx1 = ts->wridx1 = ts->size1 = 0;
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ts->rdidx2 = ts->wridx2 = ts->size2 = 0;
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/* Got a new connection, set up a tty and spawn a shell. */
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pty = getpty(tty_name);
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if (pty < 0) {
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syslog_msg(LOG_USER, LOG_ERR, "All network ports in use!");
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return 0;
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}
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if (pty > maxfd)
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maxfd = pty;
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ts->ptyfd = pty;
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/* Make the telnet client understand we will echo characters so it
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* should not do it locally. We don't tell the client to run linemode,
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* because we want to handle line editing and tab completion and other
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* stuff that requires char-by-char support.
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*/
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send_iac(ts, DO, TELOPT_ECHO);
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send_iac(ts, DO, TELOPT_LFLOW);
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send_iac(ts, WILL, TELOPT_ECHO);
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send_iac(ts, WILL, TELOPT_SGA);
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if ((pid = fork()) < 0) {
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syslog_msg(LOG_USER, LOG_ERR, "Can`t forking");
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}
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if (pid == 0) {
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/* In child, open the child's side of the tty. */
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int i;
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for(i = 0; i <= maxfd; i++)
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close(i);
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/* make new process group */
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setsid();
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if (open(tty_name, O_RDWR /*| O_NOCTTY*/) < 0) {
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syslog_msg(LOG_USER, LOG_ERR, "Could not open tty");
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exit(1);
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}
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dup(0);
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dup(0);
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tcsetpgrp(0, getpid());
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/* The pseudo-terminal allocated to the client is configured to operate in
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* cooked mode, and with XTABS CRMOD enabled (see tty(4)).
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*/
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tcgetattr(0, &termbuf);
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termbuf.c_lflag |= ECHO; /* if we use readline we dont want this */
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termbuf.c_oflag |= ONLCR|XTABS;
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termbuf.c_iflag |= ICRNL;
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termbuf.c_iflag &= ~IXOFF;
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/*termbuf.c_lflag &= ~ICANON;*/
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tcsetattr(0, TCSANOW, &termbuf);
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2003-01-22 02:25:56 +05:30
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print_login_issue(issuefile, NULL);
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2002-10-01 02:22:10 +05:30
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/* exec shell, with correct argv and env */
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execv(loginpath, (char *const *)argv_init);
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/* NOT REACHED */
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syslog_msg(LOG_USER, LOG_ERR, "execv error");
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exit(1);
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}
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ts->shell_pid = pid;
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return ts;
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}
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2003-01-22 02:25:56 +05:30
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#ifndef CONFIG_FEATURE_TELNETD_INETD
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2002-10-01 02:22:10 +05:30
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static void
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free_session(struct tsession *ts)
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{
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struct tsession *t = sessions;
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/* Unlink this telnet session from the session list. */
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if(t == ts)
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sessions = ts->next;
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else {
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while(t->next != ts)
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t = t->next;
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t->next = ts->next;
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}
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kill(ts->shell_pid, SIGKILL);
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wait4(ts->shell_pid, NULL, 0, NULL);
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close(ts->ptyfd);
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close(ts->sockfd);
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if(ts->ptyfd == maxfd || ts->sockfd == maxfd)
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maxfd--;
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if(ts->ptyfd == maxfd || ts->sockfd == maxfd)
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maxfd--;
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free(ts);
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}
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2003-01-22 02:25:56 +05:30
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#endif /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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int
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telnetd_main(int argc, char **argv)
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{
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2003-01-22 02:25:56 +05:30
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#ifndef CONFIG_FEATURE_TELNETD_INETD
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2002-10-01 02:22:10 +05:30
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struct sockaddr_in sa;
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int master_fd;
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2003-01-22 02:25:56 +05:30
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#endif /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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fd_set rdfdset, wrfdset;
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int selret;
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2003-01-22 02:25:56 +05:30
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#ifndef CONFIG_FEATURE_TELNETD_INETD
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2002-10-01 02:22:10 +05:30
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int on = 1;
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int portnbr = 23;
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2003-01-22 02:25:56 +05:30
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#endif /* CONFIG_FEATURE_TELNETD_INETD */
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2002-10-01 02:22:10 +05:30
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int c;
|
2003-01-22 02:25:56 +05:30
|
|
|
static const char options[] =
|
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
"f:l:";
|
|
|
|
#else /* CONFIG_EATURE_TELNETD_INETD */
|
|
|
|
"f:l:p:";
|
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2003-04-25 18:02:37 +05:30
|
|
|
int maxlen, w, r;
|
2002-10-01 02:22:10 +05:30
|
|
|
|
|
|
|
for (;;) {
|
2003-01-22 02:25:56 +05:30
|
|
|
c = getopt( argc, argv, options);
|
2002-10-01 02:22:10 +05:30
|
|
|
if (c == EOF) break;
|
|
|
|
switch (c) {
|
2003-01-22 02:25:56 +05:30
|
|
|
case 'f':
|
|
|
|
issuefile = strdup (optarg);
|
2002-10-01 02:22:10 +05:30
|
|
|
break;
|
|
|
|
case 'l':
|
|
|
|
loginpath = strdup (optarg);
|
|
|
|
break;
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
case 'p':
|
|
|
|
portnbr = atoi(optarg);
|
|
|
|
break;
|
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
default:
|
2003-03-19 14:43:01 +05:30
|
|
|
bb_show_usage();
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (access(loginpath, X_OK) < 0) {
|
2003-03-19 14:43:01 +05:30
|
|
|
bb_error_msg_and_die ("'%s' unavailable.", loginpath);
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
|
|
|
|
argv_init[0] = loginpath;
|
2003-01-22 02:25:56 +05:30
|
|
|
|
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
maxfd = 1;
|
2003-01-23 02:39:48 +05:30
|
|
|
sessions = make_new_session();
|
2003-01-22 02:25:56 +05:30
|
|
|
#else /* CONFIG_EATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
sessions = 0;
|
|
|
|
|
|
|
|
/* Grab a TCP socket. */
|
|
|
|
|
|
|
|
master_fd = socket(AF_INET, SOCK_STREAM, 0);
|
|
|
|
if (master_fd < 0) {
|
2003-03-19 14:43:01 +05:30
|
|
|
bb_perror_msg_and_die("socket");
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
(void)setsockopt(master_fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
|
|
|
|
|
|
|
|
/* Set it to listen to specified port. */
|
|
|
|
|
|
|
|
memset((void *)&sa, 0, sizeof(sa));
|
|
|
|
sa.sin_family = AF_INET;
|
|
|
|
sa.sin_port = htons(portnbr);
|
|
|
|
|
|
|
|
if (bind(master_fd, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
|
2003-03-19 14:43:01 +05:30
|
|
|
bb_perror_msg_and_die("bind");
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
|
|
|
|
if (listen(master_fd, 1) < 0) {
|
2003-03-19 14:43:01 +05:30
|
|
|
bb_perror_msg_and_die("listen");
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
|
|
|
|
if (daemon(0, 0) < 0)
|
2003-03-19 14:43:01 +05:30
|
|
|
bb_perror_msg_and_die("daemon");
|
2002-10-01 02:22:10 +05:30
|
|
|
|
|
|
|
|
|
|
|
maxfd = master_fd;
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
|
|
|
|
do {
|
|
|
|
struct tsession *ts;
|
|
|
|
|
|
|
|
FD_ZERO(&rdfdset);
|
|
|
|
FD_ZERO(&wrfdset);
|
|
|
|
|
|
|
|
/* select on the master socket, all telnet sockets and their
|
|
|
|
* ptys if there is room in their respective session buffers.
|
|
|
|
*/
|
|
|
|
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
2002-10-01 02:22:10 +05:30
|
|
|
FD_SET(master_fd, &rdfdset);
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
|
|
|
|
ts = sessions;
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
2002-10-01 02:22:10 +05:30
|
|
|
while (ts) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
/* buf1 is used from socket to pty
|
|
|
|
* buf2 is used from pty to socket
|
|
|
|
*/
|
|
|
|
if (ts->size1 > 0) {
|
|
|
|
FD_SET(ts->ptyfd, &wrfdset); /* can write to pty */
|
|
|
|
}
|
|
|
|
if (ts->size1 < BUFSIZE) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
FD_SET(ts->sockfd_read, &rdfdset); /* can read from socket */
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
FD_SET(ts->sockfd, &rdfdset); /* can read from socket */
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
if (ts->size2 > 0) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
FD_SET(ts->sockfd_write, &wrfdset); /* can write to socket */
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
FD_SET(ts->sockfd, &wrfdset); /* can write to socket */
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
if (ts->size2 < BUFSIZE) {
|
|
|
|
FD_SET(ts->ptyfd, &rdfdset); /* can read from pty */
|
|
|
|
}
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
2002-10-01 02:22:10 +05:30
|
|
|
ts = ts->next;
|
|
|
|
}
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
|
|
|
|
selret = select(maxfd + 1, &rdfdset, &wrfdset, 0, 0);
|
|
|
|
|
|
|
|
if (!selret)
|
|
|
|
break;
|
|
|
|
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
2002-10-01 02:22:10 +05:30
|
|
|
/* First check for and accept new sessions. */
|
|
|
|
if (FD_ISSET(master_fd, &rdfdset)) {
|
|
|
|
int fd, salen;
|
|
|
|
|
|
|
|
salen = sizeof(sa);
|
|
|
|
if ((fd = accept(master_fd, (struct sockaddr *)&sa,
|
|
|
|
&salen)) < 0) {
|
|
|
|
continue;
|
|
|
|
} else {
|
|
|
|
/* Create a new session and link it into
|
|
|
|
our active list. */
|
|
|
|
struct tsession *new_ts = make_new_session(fd);
|
|
|
|
if (new_ts) {
|
|
|
|
new_ts->next = sessions;
|
|
|
|
sessions = new_ts;
|
|
|
|
if (fd > maxfd)
|
|
|
|
maxfd = fd;
|
|
|
|
} else {
|
|
|
|
close(fd);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Then check for data tunneling. */
|
|
|
|
|
|
|
|
ts = sessions;
|
|
|
|
while (ts) { /* For all sessions... */
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
2002-10-01 02:22:10 +05:30
|
|
|
struct tsession *next = ts->next; /* in case we free ts. */
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
|
|
|
|
2002-10-01 02:22:10 +05:30
|
|
|
if (ts->size1 && FD_ISSET(ts->ptyfd, &wrfdset)) {
|
|
|
|
int num_totty;
|
|
|
|
char *ptr;
|
|
|
|
/* Write to pty from buffer 1. */
|
|
|
|
|
|
|
|
ptr = remove_iacs(ts, &num_totty);
|
|
|
|
|
|
|
|
w = write(ts->ptyfd, ptr, num_totty);
|
|
|
|
if (w < 0) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
exit(0);
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
free_session(ts);
|
|
|
|
ts = next;
|
|
|
|
continue;
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
ts->wridx1 += w;
|
|
|
|
ts->size1 -= w;
|
|
|
|
if (ts->wridx1 == BUFSIZE)
|
|
|
|
ts->wridx1 = 0;
|
|
|
|
}
|
|
|
|
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
if (ts->size2 && FD_ISSET(ts->sockfd_write, &wrfdset)) {
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
if (ts->size2 && FD_ISSET(ts->sockfd, &wrfdset)) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
/* Write to socket from buffer 2. */
|
|
|
|
maxlen = MIN(BUFSIZE - ts->wridx2, ts->size2);
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
w = write(ts->sockfd_write, ts->buf2 + ts->wridx2, maxlen);
|
|
|
|
if (w < 0)
|
|
|
|
exit(0);
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
w = write(ts->sockfd, ts->buf2 + ts->wridx2, maxlen);
|
|
|
|
if (w < 0) {
|
|
|
|
free_session(ts);
|
|
|
|
ts = next;
|
|
|
|
continue;
|
|
|
|
}
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
ts->wridx2 += w;
|
|
|
|
ts->size2 -= w;
|
|
|
|
if (ts->wridx2 == BUFSIZE)
|
|
|
|
ts->wridx2 = 0;
|
|
|
|
}
|
|
|
|
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
if (ts->size1 < BUFSIZE && FD_ISSET(ts->sockfd_read, &rdfdset)) {
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
if (ts->size1 < BUFSIZE && FD_ISSET(ts->sockfd, &rdfdset)) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
/* Read from socket to buffer 1. */
|
|
|
|
maxlen = MIN(BUFSIZE - ts->rdidx1,
|
|
|
|
BUFSIZE - ts->size1);
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
r = read(ts->sockfd_read, ts->buf1 + ts->rdidx1, maxlen);
|
|
|
|
if (!r || (r < 0 && errno != EINTR))
|
|
|
|
exit(0);
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
r = read(ts->sockfd, ts->buf1 + ts->rdidx1, maxlen);
|
|
|
|
if (!r || (r < 0 && errno != EINTR)) {
|
|
|
|
free_session(ts);
|
|
|
|
ts = next;
|
|
|
|
continue;
|
|
|
|
}
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
if(!*(ts->buf1 + ts->rdidx1 + r - 1)) {
|
|
|
|
r--;
|
|
|
|
if(!r)
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
ts->rdidx1 += r;
|
|
|
|
ts->size1 += r;
|
|
|
|
if (ts->rdidx1 == BUFSIZE)
|
|
|
|
ts->rdidx1 = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (ts->size2 < BUFSIZE && FD_ISSET(ts->ptyfd, &rdfdset)) {
|
|
|
|
/* Read from pty to buffer 2. */
|
|
|
|
maxlen = MIN(BUFSIZE - ts->rdidx2,
|
|
|
|
BUFSIZE - ts->size2);
|
|
|
|
r = read(ts->ptyfd, ts->buf2 + ts->rdidx2, maxlen);
|
|
|
|
if (!r || (r < 0 && errno != EINTR)) {
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifdef CONFIG_FEATURE_TELNETD_INETD
|
|
|
|
exit(0);
|
|
|
|
#else /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
free_session(ts);
|
|
|
|
ts = next;
|
|
|
|
continue;
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
}
|
|
|
|
ts->rdidx2 += r;
|
|
|
|
ts->size2 += r;
|
|
|
|
if (ts->rdidx2 == BUFSIZE)
|
|
|
|
ts->rdidx2 = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (ts->size1 == 0) {
|
|
|
|
ts->rdidx1 = 0;
|
|
|
|
ts->wridx1 = 0;
|
|
|
|
}
|
|
|
|
if (ts->size2 == 0) {
|
|
|
|
ts->rdidx2 = 0;
|
|
|
|
ts->wridx2 = 0;
|
|
|
|
}
|
2003-01-22 02:25:56 +05:30
|
|
|
#ifndef CONFIG_FEATURE_TELNETD_INETD
|
2002-10-01 02:22:10 +05:30
|
|
|
ts = next;
|
|
|
|
}
|
2003-01-22 02:25:56 +05:30
|
|
|
#endif /* CONFIG_FEATURE_TELNETD_INETD */
|
2002-10-01 02:22:10 +05:30
|
|
|
|
|
|
|
} while (1);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|