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1118 lines
29 KiB
C
1118 lines
29 KiB
C
/*
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*
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* clientloop.c
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*
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* Author: Tatu Ylonen <ylo@cs.hut.fi>
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*
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* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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* All rights reserved
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*
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*
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* Created: Sat Sep 23 12:23:57 1995 ylo
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*
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* The main loop for the interactive session (client side).
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*
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* SSH2 support added by Markus Friedl.
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*/
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#include "includes.h"
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RCSID("$Id: clientloop.c,v 1.26 2000/05/08 17:42:24 markus Exp $");
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#include "xmalloc.h"
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#include "ssh.h"
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#include "packet.h"
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#include "buffer.h"
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#include "authfd.h"
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#include "readconf.h"
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#include "ssh2.h"
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#include "compat.h"
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#include "channels.h"
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#include "dispatch.h"
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/* Flag indicating that stdin should be redirected from /dev/null. */
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extern int stdin_null_flag;
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/*
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* Name of the host we are connecting to. This is the name given on the
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* command line, or the HostName specified for the user-supplied name in a
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* configuration file.
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*/
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extern char *host;
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/*
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* Flag to indicate that we have received a window change signal which has
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* not yet been processed. This will cause a message indicating the new
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* window size to be sent to the server a little later. This is volatile
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* because this is updated in a signal handler.
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*/
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static volatile int received_window_change_signal = 0;
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/* Terminal modes, as saved by enter_raw_mode. */
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static struct termios saved_tio;
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/*
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* Flag indicating whether we are in raw mode. This is used by
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* enter_raw_mode and leave_raw_mode.
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*/
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static int in_raw_mode = 0;
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/* Flag indicating whether the user\'s terminal is in non-blocking mode. */
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static int in_non_blocking_mode = 0;
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/* Common data for the client loop code. */
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static int escape_pending; /* Last character was the escape character */
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static int last_was_cr; /* Last character was a newline. */
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static int exit_status; /* Used to store the exit status of the command. */
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static int stdin_eof; /* EOF has been encountered on standard error. */
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static Buffer stdin_buffer; /* Buffer for stdin data. */
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static Buffer stdout_buffer; /* Buffer for stdout data. */
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static Buffer stderr_buffer; /* Buffer for stderr data. */
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static unsigned int buffer_high;/* Soft max buffer size. */
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static int max_fd; /* Maximum file descriptor number in select(). */
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static int connection_in; /* Connection to server (input). */
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static int connection_out; /* Connection to server (output). */
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static unsigned long stdin_bytes, stdout_bytes, stderr_bytes;
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static int quit_pending; /* Set to non-zero to quit the client loop. */
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static int escape_char; /* Escape character. */
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void client_init_dispatch(void);
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int session_ident = -1;
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/* Returns the user\'s terminal to normal mode if it had been put in raw mode. */
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void
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leave_raw_mode()
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{
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if (!in_raw_mode)
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return;
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in_raw_mode = 0;
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if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0)
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perror("tcsetattr");
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fatal_remove_cleanup((void (*) (void *)) leave_raw_mode, NULL);
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}
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/* Puts the user\'s terminal in raw mode. */
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void
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enter_raw_mode()
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{
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struct termios tio;
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if (tcgetattr(fileno(stdin), &tio) < 0)
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perror("tcgetattr");
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saved_tio = tio;
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tio.c_iflag |= IGNPAR;
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tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
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tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
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#ifdef IEXTEN
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tio.c_lflag &= ~IEXTEN;
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#endif /* IEXTEN */
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tio.c_oflag &= ~OPOST;
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tio.c_cc[VMIN] = 1;
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tio.c_cc[VTIME] = 0;
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if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0)
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perror("tcsetattr");
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in_raw_mode = 1;
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fatal_add_cleanup((void (*) (void *)) leave_raw_mode, NULL);
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}
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/* Restores stdin to blocking mode. */
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void
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leave_non_blocking()
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{
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if (in_non_blocking_mode) {
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(void) fcntl(fileno(stdin), F_SETFL, 0);
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in_non_blocking_mode = 0;
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fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
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}
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}
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/* Puts stdin terminal in non-blocking mode. */
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void
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enter_non_blocking()
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{
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in_non_blocking_mode = 1;
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(void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
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fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
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}
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/*
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* Signal handler for the window change signal (SIGWINCH). This just sets a
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* flag indicating that the window has changed.
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*/
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void
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window_change_handler(int sig)
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{
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received_window_change_signal = 1;
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signal(SIGWINCH, window_change_handler);
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}
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/*
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* Signal handler for signals that cause the program to terminate. These
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* signals must be trapped to restore terminal modes.
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*/
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void
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signal_handler(int sig)
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{
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if (in_raw_mode)
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leave_raw_mode();
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if (in_non_blocking_mode)
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leave_non_blocking();
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channel_stop_listening();
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packet_close();
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fatal("Killed by signal %d.", sig);
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}
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/*
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* Returns current time in seconds from Jan 1, 1970 with the maximum
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* available resolution.
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*/
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double
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get_current_time()
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{
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struct timeval tv;
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gettimeofday(&tv, NULL);
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return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
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}
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/*
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* This is called when the interactive is entered. This checks if there is
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* an EOF coming on stdin. We must check this explicitly, as select() does
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* not appear to wake up when redirecting from /dev/null.
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*/
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void
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client_check_initial_eof_on_stdin()
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{
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int len;
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char buf[1];
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/*
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* If standard input is to be "redirected from /dev/null", we simply
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* mark that we have seen an EOF and send an EOF message to the
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* server. Otherwise, we try to read a single character; it appears
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* that for some files, such /dev/null, select() never wakes up for
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* read for this descriptor, which means that we never get EOF. This
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* way we will get the EOF if stdin comes from /dev/null or similar.
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*/
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if (stdin_null_flag) {
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/* Fake EOF on stdin. */
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debug("Sending eof.");
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stdin_eof = 1;
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packet_start(SSH_CMSG_EOF);
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packet_send();
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} else {
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enter_non_blocking();
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/* Check for immediate EOF on stdin. */
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len = read(fileno(stdin), buf, 1);
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if (len == 0) {
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/* EOF. Record that we have seen it and send EOF to server. */
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debug("Sending eof.");
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stdin_eof = 1;
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packet_start(SSH_CMSG_EOF);
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packet_send();
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} else if (len > 0) {
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/*
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* Got data. We must store the data in the buffer,
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* and also process it as an escape character if
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* appropriate.
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*/
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if ((unsigned char) buf[0] == escape_char)
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escape_pending = 1;
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else {
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buffer_append(&stdin_buffer, buf, 1);
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stdin_bytes += 1;
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}
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}
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leave_non_blocking();
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}
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}
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/*
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* Make packets from buffered stdin data, and buffer them for sending to the
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* connection.
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*/
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void
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client_make_packets_from_stdin_data()
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{
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unsigned int len;
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/* Send buffered stdin data to the server. */
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while (buffer_len(&stdin_buffer) > 0 &&
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packet_not_very_much_data_to_write()) {
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len = buffer_len(&stdin_buffer);
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/* Keep the packets at reasonable size. */
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if (len > packet_get_maxsize())
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len = packet_get_maxsize();
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packet_start(SSH_CMSG_STDIN_DATA);
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packet_put_string(buffer_ptr(&stdin_buffer), len);
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packet_send();
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buffer_consume(&stdin_buffer, len);
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/* If we have a pending EOF, send it now. */
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if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
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packet_start(SSH_CMSG_EOF);
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packet_send();
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}
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}
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}
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/*
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* Checks if the client window has changed, and sends a packet about it to
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* the server if so. The actual change is detected elsewhere (by a software
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* interrupt on Unix); this just checks the flag and sends a message if
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* appropriate.
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*/
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void
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client_check_window_change()
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{
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struct winsize ws;
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if (! received_window_change_signal)
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return;
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/** XXX race */
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received_window_change_signal = 0;
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if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
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return;
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debug("client_check_window_change: changed");
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if (compat20) {
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channel_request_start(session_ident, "window-change", 0);
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packet_put_int(ws.ws_col);
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packet_put_int(ws.ws_row);
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packet_put_int(ws.ws_xpixel);
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packet_put_int(ws.ws_ypixel);
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packet_send();
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} else {
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packet_start(SSH_CMSG_WINDOW_SIZE);
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packet_put_int(ws.ws_row);
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packet_put_int(ws.ws_col);
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packet_put_int(ws.ws_xpixel);
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packet_put_int(ws.ws_ypixel);
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packet_send();
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}
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}
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/*
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* Waits until the client can do something (some data becomes available on
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* one of the file descriptors).
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*/
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void
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client_wait_until_can_do_something(fd_set * readset, fd_set * writeset)
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{
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/*debug("client_wait_until_can_do_something"); */
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/* Initialize select masks. */
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FD_ZERO(readset);
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FD_ZERO(writeset);
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if (!compat20) {
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/* Read from the connection, unless our buffers are full. */
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if (buffer_len(&stdout_buffer) < buffer_high &&
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buffer_len(&stderr_buffer) < buffer_high &&
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channel_not_very_much_buffered_data())
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FD_SET(connection_in, readset);
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/*
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* Read from stdin, unless we have seen EOF or have very much
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* buffered data to send to the server.
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*/
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if (!stdin_eof && packet_not_very_much_data_to_write())
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FD_SET(fileno(stdin), readset);
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/* Select stdout/stderr if have data in buffer. */
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if (buffer_len(&stdout_buffer) > 0)
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FD_SET(fileno(stdout), writeset);
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if (buffer_len(&stderr_buffer) > 0)
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FD_SET(fileno(stderr), writeset);
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} else {
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FD_SET(connection_in, readset);
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}
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/* Add any selections by the channel mechanism. */
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channel_prepare_select(readset, writeset);
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/* Select server connection if have data to write to the server. */
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if (packet_have_data_to_write())
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FD_SET(connection_out, writeset);
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/* move UP XXX */
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/* Update maximum file descriptor number, if appropriate. */
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if (channel_max_fd() > max_fd)
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max_fd = channel_max_fd();
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/*
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* Wait for something to happen. This will suspend the process until
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* some selected descriptor can be read, written, or has some other
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* event pending. Note: if you want to implement SSH_MSG_IGNORE
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* messages to fool traffic analysis, this might be the place to do
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* it: just have a random timeout for the select, and send a random
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* SSH_MSG_IGNORE packet when the timeout expires.
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*/
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if (select(max_fd + 1, readset, writeset, NULL, NULL) < 0) {
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char buf[100];
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/* Some systems fail to clear these automatically. */
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FD_ZERO(readset);
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FD_ZERO(writeset);
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if (errno == EINTR)
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return;
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/* Note: we might still have data in the buffers. */
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snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
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buffer_append(&stderr_buffer, buf, strlen(buf));
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stderr_bytes += strlen(buf);
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quit_pending = 1;
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}
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}
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void
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client_suspend_self()
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{
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struct winsize oldws, newws;
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/* Flush stdout and stderr buffers. */
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if (buffer_len(&stdout_buffer) > 0)
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atomicio(write, fileno(stdout), buffer_ptr(&stdout_buffer),
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buffer_len(&stdout_buffer));
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if (buffer_len(&stderr_buffer) > 0)
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atomicio(write, fileno(stderr), buffer_ptr(&stderr_buffer),
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buffer_len(&stderr_buffer));
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leave_raw_mode();
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/*
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* Free (and clear) the buffer to reduce the amount of data that gets
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* written to swap.
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*/
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buffer_free(&stdin_buffer);
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buffer_free(&stdout_buffer);
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buffer_free(&stderr_buffer);
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/* Save old window size. */
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ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
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/* Send the suspend signal to the program itself. */
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kill(getpid(), SIGTSTP);
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/* Check if the window size has changed. */
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if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
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(oldws.ws_row != newws.ws_row ||
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oldws.ws_col != newws.ws_col ||
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oldws.ws_xpixel != newws.ws_xpixel ||
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oldws.ws_ypixel != newws.ws_ypixel))
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received_window_change_signal = 1;
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/* OK, we have been continued by the user. Reinitialize buffers. */
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buffer_init(&stdin_buffer);
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buffer_init(&stdout_buffer);
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buffer_init(&stderr_buffer);
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enter_raw_mode();
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}
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void
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client_process_net_input(fd_set * readset)
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{
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int len;
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char buf[8192];
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/*
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* Read input from the server, and add any such data to the buffer of
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* the packet subsystem.
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*/
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if (FD_ISSET(connection_in, readset)) {
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/* Read as much as possible. */
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len = read(connection_in, buf, sizeof(buf));
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/*debug("read connection_in len %d", len); XXX */
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if (len == 0) {
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/* Received EOF. The remote host has closed the connection. */
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snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
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host);
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buffer_append(&stderr_buffer, buf, strlen(buf));
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stderr_bytes += strlen(buf);
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quit_pending = 1;
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return;
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}
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/*
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* There is a kernel bug on Solaris that causes select to
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* sometimes wake up even though there is no data available.
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*/
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if (len < 0 && errno == EAGAIN)
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len = 0;
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if (len < 0) {
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/* An error has encountered. Perhaps there is a network problem. */
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snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
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host, strerror(errno));
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buffer_append(&stderr_buffer, buf, strlen(buf));
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stderr_bytes += strlen(buf);
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quit_pending = 1;
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return;
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}
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packet_process_incoming(buf, len);
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}
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}
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void
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client_process_input(fd_set * readset)
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{
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int len;
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pid_t pid;
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char buf[8192], *s;
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/* Read input from stdin. */
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if (FD_ISSET(fileno(stdin), readset)) {
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/* Read as much as possible. */
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len = read(fileno(stdin), buf, sizeof(buf));
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if (len <= 0) {
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/*
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* Received EOF or error. They are treated
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* similarly, except that an error message is printed
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* if it was an error condition.
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*/
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if (len < 0) {
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snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
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buffer_append(&stderr_buffer, buf, strlen(buf));
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stderr_bytes += strlen(buf);
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}
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/* Mark that we have seen EOF. */
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stdin_eof = 1;
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/*
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* Send an EOF message to the server unless there is
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* data in the buffer. If there is data in the
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* buffer, no message will be sent now. Code
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* elsewhere will send the EOF when the buffer
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* becomes empty if stdin_eof is set.
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*/
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if (buffer_len(&stdin_buffer) == 0) {
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packet_start(SSH_CMSG_EOF);
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packet_send();
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}
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} else if (escape_char == -1) {
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/*
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* Normal successful read, and no escape character.
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* Just append the data to buffer.
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*/
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buffer_append(&stdin_buffer, buf, len);
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stdin_bytes += len;
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} else {
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/*
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* Normal, successful read. But we have an escape character
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* and have to process the characters one by one.
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*/
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unsigned int i;
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for (i = 0; i < len; i++) {
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unsigned char ch;
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/* Get one character at a time. */
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ch = buf[i];
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|
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if (escape_pending) {
|
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/* We have previously seen an escape character. */
|
|
/* Clear the flag now. */
|
|
escape_pending = 0;
|
|
/* Process the escaped character. */
|
|
switch (ch) {
|
|
case '.':
|
|
/* Terminate the connection. */
|
|
snprintf(buf, sizeof buf, "%c.\r\n", escape_char);
|
|
buffer_append(&stderr_buffer, buf, strlen(buf));
|
|
stderr_bytes += strlen(buf);
|
|
quit_pending = 1;
|
|
return;
|
|
|
|
case 'Z' - 64:
|
|
/* Suspend the program. */
|
|
/* Print a message to that effect to the user. */
|
|
snprintf(buf, sizeof buf, "%c^Z\r\n", escape_char);
|
|
buffer_append(&stderr_buffer, buf, strlen(buf));
|
|
stderr_bytes += strlen(buf);
|
|
|
|
/* Restore terminal modes and suspend. */
|
|
client_suspend_self();
|
|
|
|
/* We have been continued. */
|
|
continue;
|
|
|
|
case '&':
|
|
/*
|
|
* Detach the program (continue to serve connections,
|
|
* but put in background and no more new connections).
|
|
*/
|
|
if (!stdin_eof) {
|
|
/*
|
|
* Sending SSH_CMSG_EOF alone does not always appear
|
|
* to be enough. So we try to send an EOF character
|
|
* first.
|
|
*/
|
|
packet_start(SSH_CMSG_STDIN_DATA);
|
|
packet_put_string("\004", 1);
|
|
packet_send();
|
|
/* Close stdin. */
|
|
stdin_eof = 1;
|
|
if (buffer_len(&stdin_buffer) == 0) {
|
|
packet_start(SSH_CMSG_EOF);
|
|
packet_send();
|
|
}
|
|
}
|
|
/* Restore tty modes. */
|
|
leave_raw_mode();
|
|
|
|
/* Stop listening for new connections. */
|
|
channel_stop_listening();
|
|
|
|
printf("%c& [backgrounded]\n", escape_char);
|
|
|
|
/* Fork into background. */
|
|
pid = fork();
|
|
if (pid < 0) {
|
|
error("fork: %.100s", strerror(errno));
|
|
continue;
|
|
}
|
|
if (pid != 0) { /* This is the parent. */
|
|
/* The parent just exits. */
|
|
exit(0);
|
|
}
|
|
/* The child continues serving connections. */
|
|
continue;
|
|
|
|
case '?':
|
|
snprintf(buf, sizeof buf,
|
|
"%c?\r\n\
|
|
Supported escape sequences:\r\n\
|
|
~. - terminate connection\r\n\
|
|
~^Z - suspend ssh\r\n\
|
|
~# - list forwarded connections\r\n\
|
|
~& - background ssh (when waiting for connections to terminate)\r\n\
|
|
~? - this message\r\n\
|
|
~~ - send the escape character by typing it twice\r\n\
|
|
(Note that escapes are only recognized immediately after newline.)\r\n",
|
|
escape_char);
|
|
buffer_append(&stderr_buffer, buf, strlen(buf));
|
|
continue;
|
|
|
|
case '#':
|
|
snprintf(buf, sizeof buf, "%c#\r\n", escape_char);
|
|
buffer_append(&stderr_buffer, buf, strlen(buf));
|
|
s = channel_open_message();
|
|
buffer_append(&stderr_buffer, s, strlen(s));
|
|
xfree(s);
|
|
continue;
|
|
|
|
default:
|
|
if (ch != escape_char) {
|
|
/*
|
|
* Escape character followed by non-special character.
|
|
* Append both to the input buffer.
|
|
*/
|
|
buf[0] = escape_char;
|
|
buf[1] = ch;
|
|
buffer_append(&stdin_buffer, buf, 2);
|
|
stdin_bytes += 2;
|
|
continue;
|
|
}
|
|
/*
|
|
* Note that escape character typed twice
|
|
* falls through here; the latter gets processed
|
|
* as a normal character below.
|
|
*/
|
|
break;
|
|
}
|
|
} else {
|
|
/*
|
|
* The previous character was not an escape char. Check if this
|
|
* is an escape.
|
|
*/
|
|
if (last_was_cr && ch == escape_char) {
|
|
/* It is. Set the flag and continue to next character. */
|
|
escape_pending = 1;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Normal character. Record whether it was a newline,
|
|
* and append it to the buffer.
|
|
*/
|
|
last_was_cr = (ch == '\r' || ch == '\n');
|
|
buf[0] = ch;
|
|
buffer_append(&stdin_buffer, buf, 1);
|
|
stdin_bytes += 1;
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
client_process_output(fd_set * writeset)
|
|
{
|
|
int len;
|
|
char buf[100];
|
|
|
|
/* Write buffered output to stdout. */
|
|
if (FD_ISSET(fileno(stdout), writeset)) {
|
|
/* Write as much data as possible. */
|
|
len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
|
|
buffer_len(&stdout_buffer));
|
|
if (len <= 0) {
|
|
if (errno == EAGAIN)
|
|
len = 0;
|
|
else {
|
|
/*
|
|
* An error or EOF was encountered. Put an
|
|
* error message to stderr buffer.
|
|
*/
|
|
snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
|
|
buffer_append(&stderr_buffer, buf, strlen(buf));
|
|
stderr_bytes += strlen(buf);
|
|
quit_pending = 1;
|
|
return;
|
|
}
|
|
}
|
|
/* Consume printed data from the buffer. */
|
|
buffer_consume(&stdout_buffer, len);
|
|
}
|
|
/* Write buffered output to stderr. */
|
|
if (FD_ISSET(fileno(stderr), writeset)) {
|
|
/* Write as much data as possible. */
|
|
len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
|
|
buffer_len(&stderr_buffer));
|
|
if (len <= 0) {
|
|
if (errno == EAGAIN)
|
|
len = 0;
|
|
else {
|
|
/* EOF or error, but can't even print error message. */
|
|
quit_pending = 1;
|
|
return;
|
|
}
|
|
}
|
|
/* Consume printed characters from the buffer. */
|
|
buffer_consume(&stderr_buffer, len);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Get packets from the connection input buffer, and process them as long as
|
|
* there are packets available.
|
|
*
|
|
* Any unknown packets received during the actual
|
|
* session cause the session to terminate. This is
|
|
* intended to make debugging easier since no
|
|
* confirmations are sent. Any compatible protocol
|
|
* extensions must be negotiated during the
|
|
* preparatory phase.
|
|
*/
|
|
|
|
void
|
|
client_process_buffered_input_packets()
|
|
{
|
|
dispatch_run(DISPATCH_NONBLOCK, &quit_pending);
|
|
}
|
|
|
|
/*
|
|
* Implements the interactive session with the server. This is called after
|
|
* the user has been authenticated, and a command has been started on the
|
|
* remote host. If escape_char != -1, it is the character used as an escape
|
|
* character for terminating or suspending the session.
|
|
*/
|
|
|
|
int
|
|
client_loop(int have_pty, int escape_char_arg)
|
|
{
|
|
extern Options options;
|
|
double start_time, total_time;
|
|
int len;
|
|
char buf[100];
|
|
|
|
debug("Entering interactive session.");
|
|
|
|
start_time = get_current_time();
|
|
|
|
/* Initialize variables. */
|
|
escape_pending = 0;
|
|
last_was_cr = 1;
|
|
exit_status = -1;
|
|
stdin_eof = 0;
|
|
buffer_high = 64 * 1024;
|
|
connection_in = packet_get_connection_in();
|
|
connection_out = packet_get_connection_out();
|
|
max_fd = connection_in;
|
|
if (connection_out > max_fd)
|
|
max_fd = connection_out;
|
|
stdin_bytes = 0;
|
|
stdout_bytes = 0;
|
|
stderr_bytes = 0;
|
|
quit_pending = 0;
|
|
escape_char = escape_char_arg;
|
|
|
|
/* Initialize buffers. */
|
|
buffer_init(&stdin_buffer);
|
|
buffer_init(&stdout_buffer);
|
|
buffer_init(&stderr_buffer);
|
|
|
|
client_init_dispatch();
|
|
|
|
/* Set signal handlers to restore non-blocking mode. */
|
|
signal(SIGINT, signal_handler);
|
|
signal(SIGQUIT, signal_handler);
|
|
signal(SIGTERM, signal_handler);
|
|
signal(SIGPIPE, SIG_IGN);
|
|
if (have_pty)
|
|
signal(SIGWINCH, window_change_handler);
|
|
|
|
if (have_pty)
|
|
enter_raw_mode();
|
|
|
|
/* Check if we should immediately send of on stdin. */
|
|
if (!compat20)
|
|
client_check_initial_eof_on_stdin();
|
|
|
|
/* Main loop of the client for the interactive session mode. */
|
|
while (!quit_pending) {
|
|
fd_set readset, writeset;
|
|
|
|
/* Process buffered packets sent by the server. */
|
|
client_process_buffered_input_packets();
|
|
|
|
if (compat20 && !channel_still_open()) {
|
|
debug("!channel_still_open.");
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Make packets of buffered stdin data, and buffer them for
|
|
* sending to the server.
|
|
*/
|
|
if (!compat20)
|
|
client_make_packets_from_stdin_data();
|
|
|
|
/*
|
|
* Make packets from buffered channel data, and buffer them
|
|
* for sending to the server.
|
|
*/
|
|
if (packet_not_very_much_data_to_write())
|
|
channel_output_poll();
|
|
|
|
/*
|
|
* Check if the window size has changed, and buffer a message
|
|
* about it to the server if so.
|
|
*/
|
|
client_check_window_change();
|
|
|
|
if (quit_pending)
|
|
break;
|
|
|
|
/*
|
|
* Wait until we have something to do (something becomes
|
|
* available on one of the descriptors).
|
|
*/
|
|
client_wait_until_can_do_something(&readset, &writeset);
|
|
|
|
if (quit_pending)
|
|
break;
|
|
|
|
/* Do channel operations. */
|
|
channel_after_select(&readset, &writeset);
|
|
|
|
/* Buffer input from the connection. */
|
|
client_process_net_input(&readset);
|
|
|
|
if (quit_pending)
|
|
break;
|
|
|
|
if (!compat20) {
|
|
/* Buffer data from stdin */
|
|
client_process_input(&readset);
|
|
/*
|
|
* Process output to stdout and stderr. Output to
|
|
* the connection is processed elsewhere (above).
|
|
*/
|
|
client_process_output(&writeset);
|
|
}
|
|
|
|
/* Send as much buffered packet data as possible to the sender. */
|
|
if (FD_ISSET(connection_out, &writeset))
|
|
packet_write_poll();
|
|
}
|
|
|
|
/* Terminate the session. */
|
|
|
|
/* Stop watching for window change. */
|
|
if (have_pty)
|
|
signal(SIGWINCH, SIG_DFL);
|
|
|
|
/* Stop listening for connections. */
|
|
channel_stop_listening();
|
|
|
|
/*
|
|
* In interactive mode (with pseudo tty) display a message indicating
|
|
* that the connection has been closed.
|
|
*/
|
|
if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
|
|
snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
|
|
buffer_append(&stderr_buffer, buf, strlen(buf));
|
|
stderr_bytes += strlen(buf);
|
|
}
|
|
/* Output any buffered data for stdout. */
|
|
while (buffer_len(&stdout_buffer) > 0) {
|
|
len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
|
|
buffer_len(&stdout_buffer));
|
|
if (len <= 0) {
|
|
error("Write failed flushing stdout buffer.");
|
|
break;
|
|
}
|
|
buffer_consume(&stdout_buffer, len);
|
|
}
|
|
|
|
/* Output any buffered data for stderr. */
|
|
while (buffer_len(&stderr_buffer) > 0) {
|
|
len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
|
|
buffer_len(&stderr_buffer));
|
|
if (len <= 0) {
|
|
error("Write failed flushing stderr buffer.");
|
|
break;
|
|
}
|
|
buffer_consume(&stderr_buffer, len);
|
|
}
|
|
|
|
if (have_pty)
|
|
leave_raw_mode();
|
|
|
|
/* Clear and free any buffers. */
|
|
memset(buf, 0, sizeof(buf));
|
|
buffer_free(&stdin_buffer);
|
|
buffer_free(&stdout_buffer);
|
|
buffer_free(&stderr_buffer);
|
|
|
|
/* Report bytes transferred, and transfer rates. */
|
|
total_time = get_current_time() - start_time;
|
|
debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
|
|
stdin_bytes, stdout_bytes, stderr_bytes, total_time);
|
|
if (total_time > 0)
|
|
debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
|
|
stdin_bytes / total_time, stdout_bytes / total_time,
|
|
stderr_bytes / total_time);
|
|
|
|
/* Return the exit status of the program. */
|
|
debug("Exit status %d", exit_status);
|
|
return exit_status;
|
|
}
|
|
|
|
/*********/
|
|
|
|
void
|
|
client_input_stdout_data(int type, int plen)
|
|
{
|
|
unsigned int data_len;
|
|
char *data = packet_get_string(&data_len);
|
|
packet_integrity_check(plen, 4 + data_len, type);
|
|
buffer_append(&stdout_buffer, data, data_len);
|
|
stdout_bytes += data_len;
|
|
memset(data, 0, data_len);
|
|
xfree(data);
|
|
}
|
|
void
|
|
client_input_stderr_data(int type, int plen)
|
|
{
|
|
unsigned int data_len;
|
|
char *data = packet_get_string(&data_len);
|
|
packet_integrity_check(plen, 4 + data_len, type);
|
|
buffer_append(&stderr_buffer, data, data_len);
|
|
stdout_bytes += data_len;
|
|
memset(data, 0, data_len);
|
|
xfree(data);
|
|
}
|
|
void
|
|
client_input_exit_status(int type, int plen)
|
|
{
|
|
packet_integrity_check(plen, 4, type);
|
|
exit_status = packet_get_int();
|
|
/* Acknowledge the exit. */
|
|
packet_start(SSH_CMSG_EXIT_CONFIRMATION);
|
|
packet_send();
|
|
/*
|
|
* Must wait for packet to be sent since we are
|
|
* exiting the loop.
|
|
*/
|
|
packet_write_wait();
|
|
/* Flag that we want to exit. */
|
|
quit_pending = 1;
|
|
}
|
|
|
|
/* XXXX move to generic input handler */
|
|
void
|
|
client_input_channel_open(int type, int plen)
|
|
{
|
|
Channel *c = NULL;
|
|
char *ctype;
|
|
int id;
|
|
unsigned int len;
|
|
int rchan;
|
|
int rmaxpack;
|
|
int rwindow;
|
|
|
|
ctype = packet_get_string(&len);
|
|
rchan = packet_get_int();
|
|
rwindow = packet_get_int();
|
|
rmaxpack = packet_get_int();
|
|
|
|
debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
|
|
ctype, rchan, rwindow, rmaxpack);
|
|
|
|
if (strcmp(ctype, "x11") == 0) {
|
|
int sock;
|
|
char *originator;
|
|
int originator_port;
|
|
originator = packet_get_string(NULL);
|
|
if (datafellows & SSH_BUG_X11FWD) {
|
|
debug("buggy server: x11 request w/o originator_port");
|
|
originator_port = 0;
|
|
} else {
|
|
originator_port = packet_get_int();
|
|
}
|
|
packet_done();
|
|
/* XXX check permission */
|
|
xfree(originator);
|
|
/* XXX move to channels.c */
|
|
sock = x11_connect_display();
|
|
if (sock >= 0) {
|
|
id = channel_new("x11", SSH_CHANNEL_X11_OPEN,
|
|
sock, sock, -1, 4*1024, 32*1024, 0,
|
|
xstrdup("x11"));
|
|
c = channel_lookup(id);
|
|
}
|
|
}
|
|
/* XXX duplicate : */
|
|
if (c != NULL) {
|
|
debug("confirm %s", ctype);
|
|
c->remote_id = rchan;
|
|
c->remote_window = rwindow;
|
|
c->remote_maxpacket = rmaxpack;
|
|
|
|
packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
|
|
packet_put_int(c->remote_id);
|
|
packet_put_int(c->self);
|
|
packet_put_int(c->local_window);
|
|
packet_put_int(c->local_maxpacket);
|
|
packet_send();
|
|
} else {
|
|
debug("failure %s", ctype);
|
|
packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
|
|
packet_put_int(rchan);
|
|
packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
|
|
packet_put_cstring("bla bla");
|
|
packet_put_cstring("");
|
|
packet_send();
|
|
}
|
|
xfree(ctype);
|
|
}
|
|
|
|
void
|
|
client_init_dispatch_20()
|
|
{
|
|
dispatch_init(&dispatch_protocol_error);
|
|
dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
|
|
dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
|
|
dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
|
|
dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
|
|
dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
|
|
dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
|
|
dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
|
|
dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &channel_input_channel_request);
|
|
dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
|
|
}
|
|
void
|
|
client_init_dispatch_13()
|
|
{
|
|
dispatch_init(NULL);
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
|
|
dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
|
|
dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
|
|
dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
|
|
dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
|
|
dispatch_set(SSH_SMSG_AGENT_OPEN, &auth_input_open_request);
|
|
dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
|
|
dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
|
|
dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
|
|
dispatch_set(SSH_SMSG_X11_OPEN, &x11_input_open);
|
|
}
|
|
void
|
|
client_init_dispatch_15()
|
|
{
|
|
client_init_dispatch_13();
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
|
|
}
|
|
void
|
|
client_init_dispatch()
|
|
{
|
|
if (compat20)
|
|
client_init_dispatch_20();
|
|
else if (compat13)
|
|
client_init_dispatch_13();
|
|
else
|
|
client_init_dispatch_15();
|
|
}
|
|
|
|
void
|
|
client_input_channel_req(int id, void *arg)
|
|
{
|
|
Channel *c = NULL;
|
|
unsigned int len;
|
|
int success = 0;
|
|
int reply;
|
|
char *rtype;
|
|
|
|
rtype = packet_get_string(&len);
|
|
reply = packet_get_char();
|
|
|
|
debug("client_input_channel_req: rtype %s reply %d", rtype, reply);
|
|
|
|
c = channel_lookup(id);
|
|
if (c == NULL)
|
|
fatal("session_input_channel_req: channel %d: bad channel", id);
|
|
|
|
if (session_ident == -1) {
|
|
error("client_input_channel_req: no channel %d", id);
|
|
} else if (id != session_ident) {
|
|
error("client_input_channel_req: bad channel %d != %d",
|
|
id, session_ident);
|
|
} else if (strcmp(rtype, "exit-status") == 0) {
|
|
success = 1;
|
|
exit_status = packet_get_int();
|
|
packet_done();
|
|
}
|
|
if (reply) {
|
|
packet_start(success ?
|
|
SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
|
|
packet_put_int(c->remote_id);
|
|
packet_send();
|
|
}
|
|
xfree(rtype);
|
|
}
|
|
|
|
void
|
|
client_set_session_ident(int id)
|
|
{
|
|
debug("client_set_session_ident: id %d", id);
|
|
session_ident = id;
|
|
channel_register_callback(id, SSH2_MSG_CHANNEL_REQUEST,
|
|
client_input_channel_req, (void *)0);
|
|
}
|