static void
client_alive_check(void)
{
static int had_channel = 0;
int id;
id = channel_find_open();
if (id == -1) {
if (!had_channel)
return;
packet_disconnect("No open channels after timeout!");
}
had_channel = 1;
/* timeout, check to see how many we have had */
if (++client_alive_timeouts > options.client_alive_count_max)
packet_disconnect("Timeout, your session not responding.");
/*
* send a bogus channel request with "wantreply",
* we should get back a failure
*/
channel_request_start(id, "*****@*****.**", 1);
packet_send();
}
/* request pty/x11/agent/tcpfwd/shell for channel */
static void
ssh_session2_setup(int id, int success, void *arg)
{
extern char **environ;
const char *display;
int interactive = tty_flag;
if (!success)
return; /* No need for error message, channels code sens one */
display = getenv("DISPLAY");
if (options.forward_x11 && display != NULL) {
char *proto, *data;
/* Get reasonable local authentication information. */
client_x11_get_proto(display, options.xauth_location,
options.forward_x11_trusted,
options.forward_x11_timeout, &proto, &data);
/* Request forwarding with authentication spoofing. */
debug("Requesting X11 forwarding with authentication "
"spoofing.");
x11_request_forwarding_with_spoofing(id, display, proto, data);
interactive = 1;
/* XXX wait for reply */
}
check_agent_present();
if (options.forward_agent) {
debug("Requesting authentication agent forwarding.");
channel_request_start(id, "*****@*****.**", 0);
packet_send();
}
client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
NULL, fileno(stdin), &command, environ);
}
static void
client_check_window_change(void)
{
struct winsize ws;
if (! received_window_change_signal)
return;
/** XXX race */
received_window_change_signal = 0;
if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
return;
debug2("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();
}
}
static void
client_alive_check(struct ssh *ssh)
{
u_int channel_id;
int r;
/* timeout, check to see how many we have had */
if (ssh_packet_inc_alive_timeouts(ssh) > options.client_alive_count_max) {
logit("Timeout, client not responding.");
cleanup_exit(255);
}
/*
* send a bogus global/channel request with "wantreply",
* we should get back a failure
*/
if ((channel_id = channel_find_open()) == CHANNEL_ID_NONE) {
if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
(r = sshpkt_put_cstring(ssh, "*****@*****.**"))
!= 0 ||
(r = sshpkt_put_u8(ssh, 1)) != 0) /* boolean: want reply */
fatal("%s: %s", __func__, ssh_err(r));
} else {
channel_request_start(channel_id, "*****@*****.**", 1);
}
if ((r = sshpkt_send(ssh)) != 0)
fatal("%s: %s", __func__, ssh_err(r));
}
/* request pty/x11/agent/tcpfwd/shell for channel */
static void
ssh_session2_setup(int id, int success, void *arg)
{
extern char **environ;
const char *display;
int interactive = tty_flag;
if (!success)
return; /* No need for error message, channels code sens one */
display = getenv("DISPLAY");
if (options.forward_x11 && display != NULL) {
char *proto, *data;
/* Get reasonable local authentication information. */
client_x11_get_proto(display, options.xauth_location,
options.forward_x11_trusted,
options.forward_x11_timeout, &proto, &data);
/* Request forwarding with authentication spoofing. */
debug("Requesting X11 forwarding with authentication "
"spoofing.");
x11_request_forwarding_with_spoofing(id, display, proto,
data, 1);
client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
/* XXX exit_on_forward_failure */
interactive = 1;
}
check_agent_present();
if (options.forward_agent) {
debug("Requesting authentication agent forwarding.");
channel_request_start(id, "*****@*****.**", 0);
packet_send();
}
/* Tell the packet module whether this is an interactive session. */
packet_set_interactive(interactive,
options.ip_qos_interactive, options.ip_qos_bulk);
client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
NULL, fileno(stdin), &command, environ);
}
static void
client_alive_check(void)
{
int channel_id;
/* timeout, check to see how many we have had */
if (packet_inc_alive_timeouts() > options.client_alive_count_max) {
logit("Timeout, client not responding.");
cleanup_exit(255);
}
/*
* send a bogus global/channel request with "wantreply",
* we should get back a failure
*/
if ((channel_id = channel_find_open()) == -1) {
packet_start(SSH2_MSG_GLOBAL_REQUEST);
packet_put_cstring("*****@*****.**");
packet_put_char(1); /* boolean: want reply */
} else {
channel_request_start(channel_id, "*****@*****.**", 1);
}
packet_send();
}
/* process the characters one by one */
static int
process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
{
char string[1024];
pid_t pid;
int bytes = 0;
u_int i;
u_char ch;
char *s;
for (i = 0; i < len; i++) {
/* 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(string, sizeof string, "%c.\r\n", escape_char);
buffer_append(berr, string, strlen(string));
quit_pending = 1;
return -1;
case 'Z' - 64:
/* Suspend the program. */
/* Print a message to that effect to the user. */
snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
buffer_append(berr, string, strlen(string));
/* Restore terminal modes and suspend. */
client_suspend_self(bin, bout, berr);
/* We have been continued. */
continue;
case 'B':
if (compat20) {
snprintf(string, sizeof string,
"%cB\r\n", escape_char);
buffer_append(berr, string,
strlen(string));
channel_request_start(session_ident,
"break", 0);
packet_put_int(1000);
packet_send();
}
continue;
case 'R':
if (compat20) {
if (datafellows & SSH_BUG_NOREKEY)
logit("Server does not support re-keying");
else
need_rekeying = 1;
}
continue;
case '&':
/*
* Detach the program (continue to serve connections,
* but put in background and no more new connections).
*/
/* Restore tty modes. */
leave_raw_mode();
/* Stop listening for new connections. */
channel_stop_listening();
snprintf(string, sizeof string,
"%c& [backgrounded]\n", escape_char);
buffer_append(berr, string, strlen(string));
/* 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. */
if (compat20) {
buffer_append(bin, "\004", 1);
/* fake EOF on stdin */
return -1;
} else 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(bin) == 0) {
packet_start(SSH_CMSG_EOF);
packet_send();
}
}
continue;
case '?':
snprintf(string, sizeof string,
"%c?\r\n\
Supported escape sequences:\r\n\
%c. - terminate connection\r\n\
%cB - send a BREAK to the remote system\r\n\
%cC - open a command line\r\n\
%cR - Request rekey (SSH protocol 2 only)\r\n\
%c^Z - suspend ssh\r\n\
%c# - list forwarded connections\r\n\
%c& - background ssh (when waiting for connections to terminate)\r\n\
%c? - this message\r\n\
%c%c - send the escape character by typing it twice\r\n\
(Note that escapes are only recognized immediately after newline.)\r\n",
escape_char, escape_char, escape_char, escape_char,
escape_char, escape_char, escape_char, escape_char,
escape_char, escape_char, escape_char);
buffer_append(berr, string, strlen(string));
continue;
case '#':
snprintf(string, sizeof string, "%c#\r\n", escape_char);
buffer_append(berr, string, strlen(string));
s = channel_open_message();
buffer_append(berr, s, strlen(s));
xfree(s);
continue;
case 'C':
process_cmdline();
continue;
default:
if (ch != escape_char) {
buffer_put_char(bin, escape_char);
bytes++;
}
/* Escaped characters fall through here */
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');
buffer_put_char(bin, ch);
bytes++;
}