/*
- *
- * 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).
- *
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
+ *
+ * Copyright (c) 1999 Theo de Raadt. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * SSH2 support added by Markus Friedl.
+ * Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
-RCSID("$Id$");
+RCSID("$OpenBSD: clientloop.c,v 1.39 2000/10/27 07:48:22 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"
+
+#include "buffer.h"
+#include "bufaux.h"
+
+
+/* import options */
+extern Options options;
+
/* 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. */
+/*
+ * 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. */
+/*
+ * 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. */
+/*
+ * 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 quit_pending; /* Set to non-zero to quit the client loop. */
+static int escape_char; /* Escape character. */
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 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 long stdin_bytes, stdout_bytes, stderr_bytes;
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. */
-/* Returns the user\'s terminal to normal mode if it had been put in raw
- mode. */
-void
+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)
/* Puts the user\'s terminal in raw mode. */
-void
+void
enter_raw_mode()
{
struct termios tio;
/* Restores stdin to blocking mode. */
-void
+void
leave_non_blocking()
{
if (in_non_blocking_mode) {
/* Puts stdin terminal in non-blocking mode. */
-void
+void
enter_non_blocking()
{
in_non_blocking_mode = 1;
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. */
+/*
+ * Signal handler for the window change signal (SIGWINCH). This just sets a
+ * flag indicating that the window has changed.
+ */
-void
+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. */
+/*
+ * Signal handler for signals that cause the program to terminate. These
+ * signals must be trapped to restore terminal modes.
+ */
-void
+void
signal_handler(int sig)
{
if (in_raw_mode)
fatal("Killed by signal %d.", sig);
}
-/* Returns current time in seconds from Jan 1, 1970 with the maximum available
- resolution. */
+/*
+ * Returns current time in seconds from Jan 1, 1970 with the maximum
+ * available resolution.
+ */
-double
+double
get_current_time()
{
struct timeval tv;
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. */
+/*
+ * 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
+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 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.");
packet_start(SSH_CMSG_EOF);
packet_send();
} else {
- /* Enter non-blocking mode for stdin. */
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. */
+ /* 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. */
+ /*
+ * 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 {
stdin_bytes += 1;
}
}
- /* Leave non-blocking mode. */
leave_non_blocking();
}
}
-/* Get packets from the connection input buffer, and process them as long
- as there are packets available. */
-void
-client_process_buffered_input_packets()
-{
- int type;
- char *data;
- unsigned int data_len;
- int payload_len;
-
- /* Process any buffered packets from the server. */
- while (!quit_pending &&
- (type = packet_read_poll(&payload_len)) != SSH_MSG_NONE) {
- switch (type) {
-
- case SSH_SMSG_STDOUT_DATA:
- data = packet_get_string(&data_len);
- packet_integrity_check(payload_len, 4 + data_len, type);
- buffer_append(&stdout_buffer, data, data_len);
- stdout_bytes += data_len;
- memset(data, 0, data_len);
- xfree(data);
- break;
-
- case SSH_SMSG_STDERR_DATA:
- data = packet_get_string(&data_len);
- packet_integrity_check(payload_len, 4 + data_len, type);
- buffer_append(&stderr_buffer, data, data_len);
- stdout_bytes += data_len;
- memset(data, 0, data_len);
- xfree(data);
- break;
-
- case SSH_SMSG_EXITSTATUS:
- packet_integrity_check(payload_len, 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;
- break;
-
- case SSH_SMSG_X11_OPEN:
- x11_input_open(payload_len);
- break;
-
- case SSH_MSG_PORT_OPEN:
- channel_input_port_open(payload_len);
- break;
-
- case SSH_SMSG_AGENT_OPEN:
- packet_integrity_check(payload_len, 4, type);
- auth_input_open_request();
- break;
-
- case SSH_MSG_CHANNEL_OPEN_CONFIRMATION:
- packet_integrity_check(payload_len, 4 + 4, type);
- channel_input_open_confirmation();
- break;
-
- case SSH_MSG_CHANNEL_OPEN_FAILURE:
- packet_integrity_check(payload_len, 4, type);
- channel_input_open_failure();
- break;
-
- case SSH_MSG_CHANNEL_DATA:
- channel_input_data(payload_len);
- break;
-
- case SSH_MSG_CHANNEL_CLOSE:
- packet_integrity_check(payload_len, 4, type);
- channel_input_close();
- break;
-
- case SSH_MSG_CHANNEL_CLOSE_CONFIRMATION:
- packet_integrity_check(payload_len, 4, type);
- channel_input_close_confirmation();
- break;
-
- default:
- /* 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. */
- packet_disconnect("Protocol error during session: type %d",
- type);
- }
- }
-}
-
-/* Make packets from buffered stdin data, and buffer them for sending to
- the connection. */
+/*
+ * Make packets from buffered stdin data, and buffer them for sending to the
+ * connection.
+ */
-void
+void
client_make_packets_from_stdin_data()
{
unsigned int len;
}
}
-/* 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. */
+/*
+ * 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
+void
client_check_window_change()
{
- /* Send possible window change message to the server. */
- if (received_window_change_signal) {
- struct winsize ws;
-
- /* Clear the window change indicator. */
- received_window_change_signal = 0;
-
- /* Read new window size. */
- if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) >= 0) {
- /* Successful, send the packet now. */
- 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();
- }
+ 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();
}
}
-/* Waits until the client can do something (some data becomes available on
- one of the file descriptors). */
+/*
+ * Waits until the client can do something (some data becomes available on
+ * one of the file descriptors).
+ */
-void
+void
client_wait_until_can_do_something(fd_set * readset, fd_set * writeset)
{
/* Initialize select masks. */
FD_ZERO(readset);
+ FD_ZERO(writeset);
- /* 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())
+ 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);
-
- /* 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);
-
- FD_ZERO(writeset);
+ }
/* Add any selections by the channel mechanism. */
channel_prepare_select(readset, writeset);
if (packet_have_data_to_write())
FD_SET(connection_out, writeset);
- /* Select stdout if have data in buffer. */
- if (buffer_len(&stdout_buffer) > 0)
- FD_SET(fileno(stdout), writeset);
-
- /* Select stderr if have data in buffer. */
- if (buffer_len(&stderr_buffer) > 0)
- FD_SET(fileno(stderr), 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. */
+ /*
+ * 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];
}
}
-void
-client_suspend_self()
+void
+client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
{
struct winsize oldws, newws;
/* Flush stdout and stderr buffers. */
- if (buffer_len(&stdout_buffer) > 0)
- write(fileno(stdout),
- buffer_ptr(&stdout_buffer),
- buffer_len(&stdout_buffer));
- if (buffer_len(&stderr_buffer) > 0)
- write(fileno(stderr),
- buffer_ptr(&stderr_buffer),
- buffer_len(&stderr_buffer));
-
- /* Leave raw mode. */
+ if (buffer_len(bout) > 0)
+ atomicio(write, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
+ if (buffer_len(berr) > 0)
+ atomicio(write, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
+
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);
+ /*
+ * Free (and clear) the buffer to reduce the amount of data that gets
+ * written to swap.
+ */
+ buffer_free(bin);
+ buffer_free(bout);
+ buffer_free(berr);
/* Save old window size. */
ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
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);
+ buffer_init(bin);
+ buffer_init(bout);
+ buffer_init(berr);
- /* Re-enter raw mode. */
enter_raw_mode();
}
-void
-client_process_input(fd_set * readset)
+void
+client_process_net_input(fd_set * readset)
{
- int len, pid;
- char buf[8192], *s;
+ int len;
+ char buf[8192];
- /* Read input from the server, and add any such data to the buffer
- of the packet subsystem. */
+ /*
+ * 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));
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. */
+ /*
+ * 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;
}
packet_process_incoming(buf, len);
}
+}
+
+/* process the characters one by one */
+int
+process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
+{
+ char string[1024];
+ pid_t pid;
+ int bytes = 0;
+ unsigned int i;
+ unsigned 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));
+ /*stderr_bytes += strlen(string); XXX*/
+
+ 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));
+ /*stderr_bytes += strlen(string); XXX*/
+
+ /* Restore terminal modes and suspend. */
+ client_suspend_self(bin, bout, berr);
+
+ /* We have been continued. */
+ continue;
+
+ case '&':
+ /* XXX does not work yet with proto 2 */
+ if (compat20)
+ continue;
+ /*
+ * 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(bin) == 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; /*XXX ? */
+
+ case '?':
+ snprintf(string, sizeof string,
+"%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(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;
+
+ 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++;
+ }
+ return bytes;
+}
+
+void
+client_process_input(fd_set * readset)
+{
+ int ret;
+ int len;
+ char buf[8192];
+
/* 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. */
+ /*
+ * 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));
}
/* 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. */
+ /*
+ * 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. */
+ /*
+ * 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];
-
- /* Check if we have a pending escape
- character. */
- 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;
- }
+ /*
+ * Normal, successful read. But we have an escape character
+ * and have to process the characters one by one.
+ */
+ ret = process_escapes(&stdin_buffer, &stdout_buffer, &stderr_buffer, buf, len);
+ if (ret == -1)
+ return;
+ stdout_bytes += ret;
}
}
}
-void
+void
client_process_output(fd_set * writeset)
{
int len;
if (FD_ISSET(fileno(stdout), writeset)) {
/* Write as much data as possible. */
len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
- buffer_len(&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. */
+ /*
+ * 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);
if (FD_ISSET(fileno(stderr), writeset)) {
/* Write as much data as possible. */
len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
- buffer_len(&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. */
+ /* EOF or error, but can't even print error message. */
quit_pending = 1;
return;
}
}
}
-/* 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. */
+/*
+ * 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.
+ */
-int
-client_loop(int have_pty, int escape_char_arg)
+void
+client_process_buffered_input_packets()
+{
+ dispatch_run(DISPATCH_NONBLOCK, &quit_pending, NULL);
+}
+
+/* scan buf[] for '~' before sending data to the peer */
+
+int
+simple_escape_filter(Channel *c, char *buf, int len)
+{
+ /* XXX we assume c->extended is writeable */
+ return process_escapes(&c->input, &c->output, &c->extended, buf, len);
+}
+
+/*
+ * 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, int ssh2_chan_id)
{
- extern Options options;
double start_time, total_time;
int len;
char buf[100];
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);
if (have_pty)
signal(SIGWINCH, window_change_handler);
- /* Enter raw mode if have a pseudo terminal. */
if (have_pty)
enter_raw_mode();
- /* Check if we should immediately send of on stdin. */
- client_check_initial_eof_on_stdin();
+ /* Check if we should immediately send eof on stdin. */
+ if (!compat20)
+ client_check_initial_eof_on_stdin();
+
+ if (compat20 && escape_char != -1)
+ channel_register_filter(ssh2_chan_id, simple_escape_filter);
/* Main loop of the client for the interactive session mode. */
while (!quit_pending) {
fd_set readset, writeset;
- /* Precess buffered packets sent by the server. */
+ /* Process buffered packets sent by the server. */
client_process_buffered_input_packets();
- /* Make packets of buffered stdin data, and buffer them
- for sending to the server. */
- client_make_packets_from_stdin_data();
+ if (compat20 && !channel_still_open()) {
+ debug2("!channel_still_open.");
+ break;
+ }
- /* Make packets from buffered channel data, and buffer
- them for sending to the server. */
+ /*
+ * 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. */
+ /*
+ * 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). */
+ /*
+ * 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)
/* Do channel operations. */
channel_after_select(&readset, &writeset);
- /* Process input from the connection and from stdin.
- Buffer any data that is available. */
- client_process_input(&readset);
+ /* Buffer input from the connection. */
+ client_process_net_input(&readset);
- /* Process output to stdout and stderr. Output to the
- connection is processed elsewhere (above). */
- client_process_output(&writeset);
+ if (quit_pending)
+ break;
- /* Send as much buffered packet data as possible to the
- sender. */
+ 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();
}
/* Stop listening for connections. */
channel_stop_listening();
- /* In interactive mode (with pseudo tty) display a message
- indicating that the connection has been closed. */
+ /*
+ * 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));
/* Output any buffered data for stdout. */
while (buffer_len(&stdout_buffer) > 0) {
len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
- buffer_len(&stdout_buffer));
+ buffer_len(&stdout_buffer));
if (len <= 0) {
error("Write failed flushing stdout buffer.");
break;
/* Output any buffered data for stderr. */
while (buffer_len(&stderr_buffer) > 0) {
len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
- buffer_len(&stderr_buffer));
+ buffer_len(&stderr_buffer));
if (len <= 0) {
error("Write failed flushing stderr buffer.");
break;
buffer_consume(&stderr_buffer, len);
}
- /* Leave raw mode. */
if (have_pty)
leave_raw_mode();
debug("Exit status %d", exit_status);
return exit_status;
}
+
+/*********/
+
+void
+client_input_stdout_data(int type, int plen, void *ctxt)
+{
+ 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, void *ctxt)
+{
+ 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, void *ctxt)
+{
+ 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, void *ctxt)
+{
+ 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 && options.forward_x11) {
+ int sock;
+ char *originator;
+ int originator_port;
+ originator = packet_get_string(NULL);
+ if (datafellows & SSH_BUG_X11FWD) {
+ debug2("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, CHAN_X11_WINDOW_DEFAULT,
+ CHAN_X11_PACKET_DEFAULT, 0, xstrdup("x11"), 1);
+ 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_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_AGENT_OPEN, options.forward_agent ?
+ &auth_input_open_request : &deny_input_open);
+ dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
+ &x11_input_open : &deny_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("client_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)
+{
+ debug2("client_set_session_ident: id %d", id);
+ session_ident = id;
+ channel_register_callback(id, SSH2_MSG_CHANNEL_REQUEST,
+ client_input_channel_req, (void *)0);
+}
andersk / openssh.git / blobdiff