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|
/*
*
* clientloop.c
*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
*
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
*
*
* Created: Sat Sep 23 12:23:57 1995 ylo
*
* The main loop for the interactive session (client side).
*
* SSH2 support added by Markus Friedl.
*/
#include "includes.h"
RCSID("$Id: clientloop.c,v 1.26 2000/05/08 17:42:24 markus Exp $");
#include "xmalloc.h"
#include "ssh.h"
#include "packet.h"
#include "buffer.h"
#include "authfd.h"
#include "readconf.h"
#include "ssh2.h"
#include "compat.h"
#include "channels.h"
#include "dispatch.h"
/* Flag indicating that stdin should be redirected from /dev/null. */
extern int stdin_null_flag;
/*
* Name of the host we are connecting to. This is the name given on the
* command line, or the HostName specified for the user-supplied name in a
* configuration file.
*/
extern char *host;
/*
* Flag to indicate that we have received a window change signal which has
* not yet been processed. This will cause a message indicating the new
* window size to be sent to the server a little later. This is volatile
* because this is updated in a signal handler.
*/
static volatile int received_window_change_signal = 0;
/* Terminal modes, as saved by enter_raw_mode. */
static struct termios saved_tio;
/*
* Flag indicating whether we are in raw mode. This is used by
* enter_raw_mode and leave_raw_mode.
*/
static int in_raw_mode = 0;
/* Flag indicating whether the user\'s terminal is in non-blocking mode. */
static int in_non_blocking_mode = 0;
/* Common data for the client loop code. */
static int escape_pending; /* Last character was the escape character */
static int last_was_cr; /* Last character was a newline. */
static int exit_status; /* Used to store the exit status of the command. */
static int stdin_eof; /* EOF has been encountered on standard error. */
static Buffer stdin_buffer; /* Buffer for stdin data. */
static Buffer stdout_buffer; /* Buffer for stdout data. */
static Buffer stderr_buffer; /* Buffer for stderr data. */
static unsigned int buffer_high;/* Soft max buffer size. */
static int max_fd; /* Maximum file descriptor number in select(). */
static int connection_in; /* Connection to server (input). */
static int connection_out; /* Connection to server (output). */
static unsigned long stdin_bytes, stdout_bytes, stderr_bytes;
static int quit_pending; /* Set to non-zero to quit the client loop. */
static int escape_char; /* Escape character. */
void client_init_dispatch(void);
int session_ident = -1;
/* Returns the user\'s terminal to normal mode if it had been put in raw mode. */
void
leave_raw_mode()
{
if (!in_raw_mode)
return;
in_raw_mode = 0;
if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0)
perror("tcsetattr");
fatal_remove_cleanup((void (*) (void *)) leave_raw_mode, NULL);
}
/* Puts the user\'s terminal in raw mode. */
void
enter_raw_mode()
{
struct termios tio;
if (tcgetattr(fileno(stdin), &tio) < 0)
perror("tcgetattr");
saved_tio = tio;
tio.c_iflag |= IGNPAR;
tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
#ifdef IEXTEN
tio.c_lflag &= ~IEXTEN;
#endif /* IEXTEN */
tio.c_oflag &= ~OPOST;
tio.c_cc[VMIN] = 1;
tio.c_cc[VTIME] = 0;
if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0)
perror("tcsetattr");
in_raw_mode = 1;
fatal_add_cleanup((void (*) (void *)) leave_raw_mode, NULL);
}
/* Restores stdin to blocking mode. */
void
leave_non_blocking()
{
if (in_non_blocking_mode) {
(void) fcntl(fileno(stdin), F_SETFL, 0);
in_non_blocking_mode = 0;
fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
}
}
/* Puts stdin terminal in non-blocking mode. */
void
enter_non_blocking()
{
in_non_blocking_mode = 1;
(void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
}
/*
* Signal handler for the window change signal (SIGWINCH). This just sets a
* flag indicating that the window has changed.
*/
void
window_change_handler(int sig)
{
received_window_change_signal = 1;
signal(SIGWINCH, window_change_handler);
}
/*
* Signal handler for signals that cause the program to terminate. These
* signals must be trapped to restore terminal modes.
*/
void
signal_handler(int sig)
{
if (in_raw_mode)
leave_raw_mode();
if (in_non_blocking_mode)
leave_non_blocking();
channel_stop_listening();
packet_close();
fatal("Killed by signal %d.", sig);
}
/*
* Returns current time in seconds from Jan 1, 1970 with the maximum
* available resolution.
*/
double
get_current_time()
{
struct timeval tv;
gettimeofday(&tv, NULL);
return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
}
/*
* This is called when the interactive is entered. This checks if there is
* an EOF coming on stdin. We must check this explicitly, as select() does
* not appear to wake up when redirecting from /dev/null.
*/
void
client_check_initial_eof_on_stdin()
{
int len;
char buf[1];
/*
* If standard input is to be "redirected from /dev/null", we simply
* mark that we have seen an EOF and send an EOF message to the
* server. Otherwise, we try to read a single character; it appears
* that for some files, such /dev/null, select() never wakes up for
* read for this descriptor, which means that we never get EOF. This
* way we will get the EOF if stdin comes from /dev/null or similar.
*/
if (stdin_null_flag) {
/* Fake EOF on stdin. */
debug("Sending eof.");
stdin_eof = 1;
packet_start(SSH_CMSG_EOF);
packet_send();
} else {
enter_non_blocking();
/* Check for immediate EOF on stdin. */
len = read(fileno(stdin), buf, 1);
if (len == 0) {
/* EOF. Record that we have seen it and send EOF to server. */
debug("Sending eof.");
stdin_eof = 1;
packet_start(SSH_CMSG_EOF);
packet_send();
} else if (len > 0) {
/*
* Got data. We must store the data in the buffer,
* and also process it as an escape character if
* appropriate.
*/
if ((unsigned char) buf[0] == escape_char)
escape_pending = 1;
else {
buffer_append(&stdin_buffer, buf, 1);
stdin_bytes += 1;
}
}
leave_non_blocking();
}
}
/*
* Make packets from buffered stdin data, and buffer them for sending to the
* connection.
*/
void
client_make_packets_from_stdin_data()
{
unsigned int len;
/* Send buffered stdin data to the server. */
while (buffer_len(&stdin_buffer) > 0 &&
packet_not_very_much_data_to_write()) {
len = buffer_len(&stdin_buffer);
/* Keep the packets at reasonable size. */
if (len > packet_get_maxsize())
len = packet_get_maxsize();
packet_start(SSH_CMSG_STDIN_DATA);
packet_put_string(buffer_ptr(&stdin_buffer), len);
packet_send();
buffer_consume(&stdin_buffer, len);
/* If we have a pending EOF, send it now. */
if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
packet_start(SSH_CMSG_EOF);
packet_send();
}
}
}
/*
* Checks if the client window has changed, and sends a packet about it to
* the server if so. The actual change is detected elsewhere (by a software
* interrupt on Unix); this just checks the flag and sends a message if
* appropriate.
*/
void
client_check_window_change()
{
struct winsize ws;
if (! received_window_change_signal)
return;
/** XXX race */
received_window_change_signal = 0;
if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
return;
debug("client_check_window_change: changed");
if (compat20) {
channel_request_start(session_ident, "window-change", 0);
packet_put_int(ws.ws_col);
packet_put_int(ws.ws_row);
packet_put_int(ws.ws_xpixel);
packet_put_int(ws.ws_ypixel);
packet_send();
} else {
packet_start(SSH_CMSG_WINDOW_SIZE);
packet_put_int(ws.ws_row);
packet_put_int(ws.ws_col);
packet_put_int(ws.ws_xpixel);
packet_put_int(ws.ws_ypixel);
packet_send();
}
}
/*
* Waits until the client can do something (some data becomes available on
* one of the file descriptors).
*/
void
client_wait_until_can_do_something(fd_set * readset, fd_set * writeset)
{
/*debug("client_wait_until_can_do_something"); */
/* Initialize select masks. */
FD_ZERO(readset);
FD_ZERO(writeset);
if (!compat20) {
/* Read from the connection, unless our buffers are full. */
if (buffer_len(&stdout_buffer) < buffer_high &&
buffer_len(&stderr_buffer) < buffer_high &&
channel_not_very_much_buffered_data())
FD_SET(connection_in, readset);
/*
* Read from stdin, unless we have seen EOF or have very much
* buffered data to send to the server.
*/
if (!stdin_eof && packet_not_very_much_data_to_write())
FD_SET(fileno(stdin), readset);
/* Select stdout/stderr if have data in buffer. */
if (buffer_len(&stdout_buffer) > 0)
FD_SET(fileno(stdout), writeset);
if (buffer_len(&stderr_buffer) > 0)
FD_SET(fileno(stderr), writeset);
} else {
FD_SET(connection_in, readset);
}
/* Add any selections by the channel mechanism. */
channel_prepare_select(readset, writeset);
/* Select server connection if have data to write to the server. */
if (packet_have_data_to_write())
FD_SET(connection_out, writeset);
/* move UP XXX */
/* Update maximum file descriptor number, if appropriate. */
if (channel_max_fd() > max_fd)
max_fd = channel_max_fd();
/*
* Wait for something to happen. This will suspend the process until
* some selected descriptor can be read, written, or has some other
* event pending. Note: if you want to implement SSH_MSG_IGNORE
* messages to fool traffic analysis, this might be the place to do
* it: just have a random timeout for the select, and send a random
* SSH_MSG_IGNORE packet when the timeout expires.
*/
if (select(max_fd + 1, readset, writeset, NULL, NULL) < 0) {
char buf[100];
/* Some systems fail to clear these automatically. */
FD_ZERO(readset);
FD_ZERO(writeset);
if (errno == EINTR)
return;
/* Note: we might still have data in the buffers. */
snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
buffer_append(&stderr_buffer, buf, strlen(buf));
stderr_bytes += strlen(buf);
quit_pending = 1;
}
}
void
client_suspend_self()
{
struct winsize oldws, newws;
/* Flush stdout and stderr buffers. */
if (buffer_len(&stdout_buffer) > 0)
atomicio(write, fileno(stdout), buffer_ptr(&stdout_buffer),
buffer_len(&stdout_buffer));
if (buffer_len(&stderr_buffer) > 0)
atomicio(write, fileno(stderr), buffer_ptr(&stderr_buffer),
buffer_len(&stderr_buffer));
leave_raw_mode();
/*
* Free (and clear) the buffer to reduce the amount of data that gets
* written to swap.
*/
buffer_free(&stdin_buffer);
buffer_free(&stdout_buffer);
buffer_free(&stderr_buffer);
/* Save old window size. */
ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
/* Send the suspend signal to the program itself. */
kill(getpid(), SIGTSTP);
/* Check if the window size has changed. */
if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
(oldws.ws_row != newws.ws_row ||
oldws.ws_col != newws.ws_col ||
oldws.ws_xpixel != newws.ws_xpixel ||
oldws.ws_ypixel != newws.ws_ypixel))
received_window_change_signal = 1;
/* OK, we have been continued by the user. Reinitialize buffers. */
buffer_init(&stdin_buffer);
buffer_init(&stdout_buffer);
buffer_init(&stderr_buffer);
enter_raw_mode();
}
void
client_process_net_input(fd_set * readset)
{
int len;
char buf[8192];
/*
* Read input from the server, and add any such data to the buffer of
* the packet subsystem.
*/
if (FD_ISSET(connection_in, readset)) {
/* Read as much as possible. */
len = read(connection_in, buf, sizeof(buf));
/*debug("read connection_in len %d", len); XXX */
if (len == 0) {
/* Received EOF. The remote host has closed the connection. */
snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
host);
buffer_append(&stderr_buffer, buf, strlen(buf));
stderr_bytes += strlen(buf);
quit_pending = 1;
return;
}
/*
* There is a kernel bug on Solaris that causes select to
* sometimes wake up even though there is no data available.
*/
if (len < 0 && errno == EAGAIN)
len = 0;
if (len < 0) {
/* An error has encountered. Perhaps there is a network problem. */
snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
host, strerror(errno));
buffer_append(&stderr_buffer, buf, strlen(buf));
stderr_bytes += strlen(buf);
quit_pending = 1;
return;
}
packet_process_incoming(buf, len);
}
}
void
client_process_input(fd_set * readset)
{
int len;
pid_t pid;
char buf[8192], *s;
/* Read input from stdin. */
if (FD_ISSET(fileno(stdin), readset)) {
/* Read as much as possible. */
len = read(fileno(stdin), buf, sizeof(buf));
if (len <= 0) {
/*
* Received EOF or error. They are treated
* similarly, except that an error message is printed
* if it was an error condition.
*/
if (len < 0) {
snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
buffer_append(&stderr_buffer, buf, strlen(buf));
stderr_bytes += strlen(buf);
}
/* Mark that we have seen EOF. */
stdin_eof = 1;
/*
* Send an EOF message to the server unless there is
* data in the buffer. If there is data in the
* buffer, no message will be sent now. Code
* elsewhere will send the EOF when the buffer
* becomes empty if stdin_eof is set.
*/
if (buffer_len(&stdin_buffer) == 0) {
packet_start(SSH_CMSG_EOF);
packet_send();
}
} else if (escape_char == -1) {
/*
* Normal successful read, and no escape character.
* Just append the data to buffer.
*/
buffer_append(&stdin_buffer, buf, len);
stdin_bytes += len;
} else {
/*
* Normal, successful read. But we have an escape character
* and have to process the characters one by one.
*/
unsigned int i;
for (i = 0; i < len; i++) {
unsigned char ch;
/* Get one character at a time. */
ch = buf[i];
if (escape_pending) {
/* 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);
}
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