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73298f420e
[clientloop.c mux.c]
channel_setup_local_fwd_listener() returns 0 on failure, not -ve
bz#2055 reported by mathieu.lacage AT gmail.com
2267 lines
61 KiB
C
2267 lines
61 KiB
C
/* $OpenBSD: clientloop.c,v 1.248 2013/01/02 00:32:07 djm Exp $ */
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/*
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* Author: Tatu Ylonen <ylo@cs.hut.fi>
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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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* The main loop for the interactive session (client side).
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*
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* As far as I am concerned, the code I have written for this software
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* can be used freely for any purpose. Any derived versions of this
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* software must be clearly marked as such, and if the derived work is
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* incompatible with the protocol description in the RFC file, it must be
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* called by a name other than "ssh" or "Secure Shell".
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*
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*
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* Copyright (c) 1999 Theo de Raadt. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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*
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* SSH2 support added by Markus Friedl.
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* Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
|
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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#include <sys/types.h>
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#include <sys/ioctl.h>
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#include <sys/param.h>
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#ifdef HAVE_SYS_STAT_H
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# include <sys/stat.h>
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#endif
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#ifdef HAVE_SYS_TIME_H
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# include <sys/time.h>
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#endif
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#include <sys/socket.h>
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#include <ctype.h>
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#include <errno.h>
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#ifdef HAVE_PATHS_H
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#include <paths.h>
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#endif
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#include <signal.h>
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#include <stdarg.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <termios.h>
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#include <pwd.h>
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#include <unistd.h>
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#include "openbsd-compat/sys-queue.h"
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#include "xmalloc.h"
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#include "ssh.h"
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#include "ssh1.h"
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#include "ssh2.h"
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#include "packet.h"
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#include "buffer.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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#include "key.h"
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#include "cipher.h"
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#include "kex.h"
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#include "log.h"
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#include "readconf.h"
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#include "clientloop.h"
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#include "sshconnect.h"
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#include "authfd.h"
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#include "atomicio.h"
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#include "sshpty.h"
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#include "misc.h"
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#include "match.h"
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#include "msg.h"
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#include "roaming.h"
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/* import options */
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extern Options options;
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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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/* Flag indicating that no shell has been requested */
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extern int no_shell_flag;
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/* Control socket */
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extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
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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 sig_atomic_t received_window_change_signal = 0;
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static volatile sig_atomic_t received_signal = 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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/* Time when backgrounded control master using ControlPersist should exit */
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static time_t control_persist_exit_time = 0;
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/* Common data for the client loop code. */
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volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
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static int escape_char1; /* Escape character. (proto1 only) */
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static int escape_pending1; /* Last character was an escape (proto1 only) */
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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 command exit status. */
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static int stdin_eof; /* EOF has been encountered on stderr. */
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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 u_int buffer_high; /* Soft max buffer size. */
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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 int need_rekeying; /* Set to non-zero if rekeying is requested. */
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static int session_closed; /* In SSH2: login session closed. */
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static int x11_refuse_time; /* If >0, refuse x11 opens after this time. */
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static void client_init_dispatch(void);
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int session_ident = -1;
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int session_resumed = 0;
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/* Track escape per proto2 channel */
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struct escape_filter_ctx {
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int escape_pending;
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int escape_char;
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};
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/* Context for channel confirmation replies */
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struct channel_reply_ctx {
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const char *request_type;
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int id;
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enum confirm_action action;
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};
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/* Global request success/failure callbacks */
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struct global_confirm {
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TAILQ_ENTRY(global_confirm) entry;
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global_confirm_cb *cb;
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void *ctx;
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int ref_count;
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};
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TAILQ_HEAD(global_confirms, global_confirm);
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static struct global_confirms global_confirms =
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TAILQ_HEAD_INITIALIZER(global_confirms);
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/*XXX*/
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extern Kex *xxx_kex;
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void ssh_process_session2_setup(int, int, int, Buffer *);
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/* Restores stdin to blocking mode. */
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static void
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leave_non_blocking(void)
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{
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if (in_non_blocking_mode) {
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unset_nonblock(fileno(stdin));
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in_non_blocking_mode = 0;
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}
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}
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/* Puts stdin terminal in non-blocking mode. */
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static void
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enter_non_blocking(void)
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{
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in_non_blocking_mode = 1;
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set_nonblock(fileno(stdin));
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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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/*ARGSUSED */
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static 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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/*ARGSUSED */
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static void
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signal_handler(int sig)
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{
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received_signal = sig;
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quit_pending = 1;
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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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static double
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get_current_time(void)
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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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* Sets control_persist_exit_time to the absolute time when the
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* backgrounded control master should exit due to expiry of the
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* ControlPersist timeout. Sets it to 0 if we are not a backgrounded
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* control master process, or if there is no ControlPersist timeout.
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*/
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static void
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set_control_persist_exit_time(void)
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{
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if (muxserver_sock == -1 || !options.control_persist
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|| options.control_persist_timeout == 0) {
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/* not using a ControlPersist timeout */
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control_persist_exit_time = 0;
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} else if (channel_still_open()) {
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/* some client connections are still open */
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if (control_persist_exit_time > 0)
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debug2("%s: cancel scheduled exit", __func__);
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control_persist_exit_time = 0;
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} else if (control_persist_exit_time <= 0) {
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/* a client connection has recently closed */
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control_persist_exit_time = time(NULL) +
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(time_t)options.control_persist_timeout;
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debug2("%s: schedule exit in %d seconds", __func__,
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options.control_persist_timeout);
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}
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/* else we are already counting down to the timeout */
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}
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#define SSH_X11_VALID_DISPLAY_CHARS ":/.-_"
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static int
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client_x11_display_valid(const char *display)
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{
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size_t i, dlen;
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dlen = strlen(display);
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for (i = 0; i < dlen; i++) {
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if (!isalnum(display[i]) &&
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strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) {
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debug("Invalid character '%c' in DISPLAY", display[i]);
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return 0;
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}
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}
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return 1;
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}
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#define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
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void
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client_x11_get_proto(const char *display, const char *xauth_path,
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u_int trusted, u_int timeout, char **_proto, char **_data)
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{
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char cmd[1024];
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char line[512];
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char xdisplay[512];
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static char proto[512], data[512];
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FILE *f;
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int got_data = 0, generated = 0, do_unlink = 0, i;
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char *xauthdir, *xauthfile;
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struct stat st;
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u_int now;
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xauthdir = xauthfile = NULL;
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*_proto = proto;
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*_data = data;
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proto[0] = data[0] = '\0';
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if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
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debug("No xauth program.");
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} else if (!client_x11_display_valid(display)) {
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logit("DISPLAY '%s' invalid, falling back to fake xauth data",
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display);
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} else {
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if (display == NULL) {
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debug("x11_get_proto: DISPLAY not set");
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return;
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}
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/*
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* Handle FamilyLocal case where $DISPLAY does
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* not match an authorization entry. For this we
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* just try "xauth list unix:displaynum.screennum".
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* XXX: "localhost" match to determine FamilyLocal
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* is not perfect.
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*/
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if (strncmp(display, "localhost:", 10) == 0) {
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snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
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display + 10);
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display = xdisplay;
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}
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if (trusted == 0) {
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xauthdir = xmalloc(MAXPATHLEN);
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xauthfile = xmalloc(MAXPATHLEN);
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mktemp_proto(xauthdir, MAXPATHLEN);
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if (mkdtemp(xauthdir) != NULL) {
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do_unlink = 1;
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snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
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xauthdir);
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snprintf(cmd, sizeof(cmd),
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"%s -f %s generate %s " SSH_X11_PROTO
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" untrusted timeout %u 2>" _PATH_DEVNULL,
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xauth_path, xauthfile, display, timeout);
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debug2("x11_get_proto: %s", cmd);
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if (system(cmd) == 0)
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generated = 1;
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if (x11_refuse_time == 0) {
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now = time(NULL) + 1;
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if (UINT_MAX - timeout < now)
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x11_refuse_time = UINT_MAX;
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else
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x11_refuse_time = now + timeout;
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}
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}
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}
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/*
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* When in untrusted mode, we read the cookie only if it was
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* successfully generated as an untrusted one in the step
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* above.
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*/
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if (trusted || generated) {
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snprintf(cmd, sizeof(cmd),
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"%s %s%s list %s 2>" _PATH_DEVNULL,
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xauth_path,
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generated ? "-f " : "" ,
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generated ? xauthfile : "",
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display);
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debug2("x11_get_proto: %s", cmd);
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f = popen(cmd, "r");
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if (f && fgets(line, sizeof(line), f) &&
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sscanf(line, "%*s %511s %511s", proto, data) == 2)
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got_data = 1;
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if (f)
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pclose(f);
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} else
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error("Warning: untrusted X11 forwarding setup failed: "
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"xauth key data not generated");
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}
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if (do_unlink) {
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unlink(xauthfile);
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rmdir(xauthdir);
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}
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if (xauthdir)
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xfree(xauthdir);
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if (xauthfile)
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xfree(xauthfile);
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/*
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* If we didn't get authentication data, just make up some
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* data. The forwarding code will check the validity of the
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* response anyway, and substitute this data. The X11
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* server, however, will ignore this fake data and use
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* whatever authentication mechanisms it was using otherwise
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* for the local connection.
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*/
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if (!got_data) {
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u_int32_t rnd = 0;
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logit("Warning: No xauth data; "
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"using fake authentication data for X11 forwarding.");
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strlcpy(proto, SSH_X11_PROTO, sizeof proto);
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for (i = 0; i < 16; i++) {
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if (i % 4 == 0)
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rnd = arc4random();
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snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
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rnd & 0xff);
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rnd >>= 8;
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}
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}
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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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static void
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client_check_initial_eof_on_stdin(void)
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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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|
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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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/*
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* EOF. Record that we have seen it and send
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* EOF to server.
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*/
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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
|
|
* appropriate.
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*/
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if ((u_char) buf[0] == escape_char1)
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escape_pending1 = 1;
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else
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buffer_append(&stdin_buffer, buf, 1);
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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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/*
|
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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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|
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static void
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client_make_packets_from_stdin_data(void)
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{
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u_int len;
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|
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/* Send buffered stdin data to the server. */
|
|
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. */
|
|
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);
|
|
/* 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.
|
|
*/
|
|
|
|
static void
|
|
client_check_window_change(void)
|
|
{
|
|
struct winsize ws;
|
|
|
|
if (! received_window_change_signal)
|
|
return;
|
|
/** XXX race */
|
|
received_window_change_signal = 0;
|
|
|
|
debug2("client_check_window_change: changed");
|
|
|
|
if (compat20) {
|
|
channel_send_window_changes();
|
|
} else {
|
|
if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
|
|
return;
|
|
packet_start(SSH_CMSG_WINDOW_SIZE);
|
|
packet_put_int((u_int)ws.ws_row);
|
|
packet_put_int((u_int)ws.ws_col);
|
|
packet_put_int((u_int)ws.ws_xpixel);
|
|
packet_put_int((u_int)ws.ws_ypixel);
|
|
packet_send();
|
|
}
|
|
}
|
|
|
|
static void
|
|
client_global_request_reply(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
struct global_confirm *gc;
|
|
|
|
if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
|
|
return;
|
|
if (gc->cb != NULL)
|
|
gc->cb(type, seq, gc->ctx);
|
|
if (--gc->ref_count <= 0) {
|
|
TAILQ_REMOVE(&global_confirms, gc, entry);
|
|
bzero(gc, sizeof(*gc));
|
|
xfree(gc);
|
|
}
|
|
|
|
packet_set_alive_timeouts(0);
|
|
}
|
|
|
|
static void
|
|
server_alive_check(void)
|
|
{
|
|
if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
|
|
logit("Timeout, server %s not responding.", host);
|
|
cleanup_exit(255);
|
|
}
|
|
packet_start(SSH2_MSG_GLOBAL_REQUEST);
|
|
packet_put_cstring("keepalive@openssh.com");
|
|
packet_put_char(1); /* boolean: want reply */
|
|
packet_send();
|
|
/* Insert an empty placeholder to maintain ordering */
|
|
client_register_global_confirm(NULL, NULL);
|
|
}
|
|
|
|
/*
|
|
* Waits until the client can do something (some data becomes available on
|
|
* one of the file descriptors).
|
|
*/
|
|
static void
|
|
client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
|
|
int *maxfdp, u_int *nallocp, int rekeying)
|
|
{
|
|
struct timeval tv, *tvp;
|
|
int timeout_secs;
|
|
time_t minwait_secs = 0;
|
|
int ret;
|
|
|
|
/* Add any selections by the channel mechanism. */
|
|
channel_prepare_select(readsetp, writesetp, maxfdp, nallocp,
|
|
&minwait_secs, rekeying);
|
|
|
|
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, *readsetp);
|
|
/*
|
|
* 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), *readsetp);
|
|
|
|
/* Select stdout/stderr if have data in buffer. */
|
|
if (buffer_len(&stdout_buffer) > 0)
|
|
FD_SET(fileno(stdout), *writesetp);
|
|
if (buffer_len(&stderr_buffer) > 0)
|
|
FD_SET(fileno(stderr), *writesetp);
|
|
} else {
|
|
/* channel_prepare_select could have closed the last channel */
|
|
if (session_closed && !channel_still_open() &&
|
|
!packet_have_data_to_write()) {
|
|
/* clear mask since we did not call select() */
|
|
memset(*readsetp, 0, *nallocp);
|
|
memset(*writesetp, 0, *nallocp);
|
|
return;
|
|
} else {
|
|
FD_SET(connection_in, *readsetp);
|
|
}
|
|
}
|
|
|
|
/* Select server connection if have data to write to the server. */
|
|
if (packet_have_data_to_write())
|
|
FD_SET(connection_out, *writesetp);
|
|
|
|
/*
|
|
* Wait for something to happen. This will suspend the process until
|
|
* some selected descriptor can be read, written, or has some other
|
|
* event pending, or a timeout expires.
|
|
*/
|
|
|
|
timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
|
|
if (options.server_alive_interval > 0 && compat20)
|
|
timeout_secs = options.server_alive_interval;
|
|
set_control_persist_exit_time();
|
|
if (control_persist_exit_time > 0) {
|
|
timeout_secs = MIN(timeout_secs,
|
|
control_persist_exit_time - time(NULL));
|
|
if (timeout_secs < 0)
|
|
timeout_secs = 0;
|
|
}
|
|
if (minwait_secs != 0)
|
|
timeout_secs = MIN(timeout_secs, (int)minwait_secs);
|
|
if (timeout_secs == INT_MAX)
|
|
tvp = NULL;
|
|
else {
|
|
tv.tv_sec = timeout_secs;
|
|
tv.tv_usec = 0;
|
|
tvp = &tv;
|
|
}
|
|
|
|
ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
|
|
if (ret < 0) {
|
|
char buf[100];
|
|
|
|
/*
|
|
* We have to clear the select masks, because we return.
|
|
* We have to return, because the mainloop checks for the flags
|
|
* set by the signal handlers.
|
|
*/
|
|
memset(*readsetp, 0, *nallocp);
|
|
memset(*writesetp, 0, *nallocp);
|
|
|
|
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));
|
|
quit_pending = 1;
|
|
} else if (ret == 0)
|
|
server_alive_check();
|
|
}
|
|
|
|
static void
|
|
client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
|
|
{
|
|
/* Flush stdout and stderr buffers. */
|
|
if (buffer_len(bout) > 0)
|
|
atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
|
|
buffer_len(bout));
|
|
if (buffer_len(berr) > 0)
|
|
atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
|
|
buffer_len(berr));
|
|
|
|
leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
|
|
/*
|
|
* 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);
|
|
|
|
/* Send the suspend signal to the program itself. */
|
|
kill(getpid(), SIGTSTP);
|
|
|
|
/* Reset window sizes in case they have changed */
|
|
received_window_change_signal = 1;
|
|
|
|
/* OK, we have been continued by the user. Reinitialize buffers. */
|
|
buffer_init(bin);
|
|
buffer_init(bout);
|
|
buffer_init(berr);
|
|
|
|
enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
}
|
|
|
|
static void
|
|
client_process_net_input(fd_set *readset)
|
|
{
|
|
int len, cont = 0;
|
|
char buf[SSH_IOBUFSZ];
|
|
|
|
/*
|
|
* 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 = roaming_read(connection_in, buf, sizeof(buf), &cont);
|
|
if (len == 0 && cont == 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));
|
|
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 || errno == EINTR || errno == EWOULDBLOCK))
|
|
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));
|
|
quit_pending = 1;
|
|
return;
|
|
}
|
|
packet_process_incoming(buf, len);
|
|
}
|
|
}
|
|
|
|
static void
|
|
client_status_confirm(int type, Channel *c, void *ctx)
|
|
{
|
|
struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
|
|
char errmsg[256];
|
|
int tochan;
|
|
|
|
/*
|
|
* If a TTY was explicitly requested, then a failure to allocate
|
|
* one is fatal.
|
|
*/
|
|
if (cr->action == CONFIRM_TTY &&
|
|
(options.request_tty == REQUEST_TTY_FORCE ||
|
|
options.request_tty == REQUEST_TTY_YES))
|
|
cr->action = CONFIRM_CLOSE;
|
|
|
|
/* XXX supress on mux _client_ quietmode */
|
|
tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
|
|
c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
|
|
|
|
if (type == SSH2_MSG_CHANNEL_SUCCESS) {
|
|
debug2("%s request accepted on channel %d",
|
|
cr->request_type, c->self);
|
|
} else if (type == SSH2_MSG_CHANNEL_FAILURE) {
|
|
if (tochan) {
|
|
snprintf(errmsg, sizeof(errmsg),
|
|
"%s request failed\r\n", cr->request_type);
|
|
} else {
|
|
snprintf(errmsg, sizeof(errmsg),
|
|
"%s request failed on channel %d",
|
|
cr->request_type, c->self);
|
|
}
|
|
/* If error occurred on primary session channel, then exit */
|
|
if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
|
|
fatal("%s", errmsg);
|
|
/*
|
|
* If error occurred on mux client, append to
|
|
* their stderr.
|
|
*/
|
|
if (tochan) {
|
|
buffer_append(&c->extended, errmsg,
|
|
strlen(errmsg));
|
|
} else
|
|
error("%s", errmsg);
|
|
if (cr->action == CONFIRM_TTY) {
|
|
/*
|
|
* If a TTY allocation error occurred, then arrange
|
|
* for the correct TTY to leave raw mode.
|
|
*/
|
|
if (c->self == session_ident)
|
|
leave_raw_mode(0);
|
|
else
|
|
mux_tty_alloc_failed(c);
|
|
} else if (cr->action == CONFIRM_CLOSE) {
|
|
chan_read_failed(c);
|
|
chan_write_failed(c);
|
|
}
|
|
}
|
|
xfree(cr);
|
|
}
|
|
|
|
static void
|
|
client_abandon_status_confirm(Channel *c, void *ctx)
|
|
{
|
|
xfree(ctx);
|
|
}
|
|
|
|
void
|
|
client_expect_confirm(int id, const char *request,
|
|
enum confirm_action action)
|
|
{
|
|
struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
|
|
|
|
cr->request_type = request;
|
|
cr->action = action;
|
|
|
|
channel_register_status_confirm(id, client_status_confirm,
|
|
client_abandon_status_confirm, cr);
|
|
}
|
|
|
|
void
|
|
client_register_global_confirm(global_confirm_cb *cb, void *ctx)
|
|
{
|
|
struct global_confirm *gc, *last_gc;
|
|
|
|
/* Coalesce identical callbacks */
|
|
last_gc = TAILQ_LAST(&global_confirms, global_confirms);
|
|
if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
|
|
if (++last_gc->ref_count >= INT_MAX)
|
|
fatal("%s: last_gc->ref_count = %d",
|
|
__func__, last_gc->ref_count);
|
|
return;
|
|
}
|
|
|
|
gc = xmalloc(sizeof(*gc));
|
|
gc->cb = cb;
|
|
gc->ctx = ctx;
|
|
gc->ref_count = 1;
|
|
TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
|
|
}
|
|
|
|
static void
|
|
process_cmdline(void)
|
|
{
|
|
void (*handler)(int);
|
|
char *s, *cmd, *cancel_host;
|
|
int delete = 0, local = 0, remote = 0, dynamic = 0;
|
|
int cancel_port, ok;
|
|
Forward fwd;
|
|
|
|
bzero(&fwd, sizeof(fwd));
|
|
fwd.listen_host = fwd.connect_host = NULL;
|
|
|
|
leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
handler = signal(SIGINT, SIG_IGN);
|
|
cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
|
|
if (s == NULL)
|
|
goto out;
|
|
while (isspace(*s))
|
|
s++;
|
|
if (*s == '-')
|
|
s++; /* Skip cmdline '-', if any */
|
|
if (*s == '\0')
|
|
goto out;
|
|
|
|
if (*s == 'h' || *s == 'H' || *s == '?') {
|
|
logit("Commands:");
|
|
logit(" -L[bind_address:]port:host:hostport "
|
|
"Request local forward");
|
|
logit(" -R[bind_address:]port:host:hostport "
|
|
"Request remote forward");
|
|
logit(" -D[bind_address:]port "
|
|
"Request dynamic forward");
|
|
logit(" -KL[bind_address:]port "
|
|
"Cancel local forward");
|
|
logit(" -KR[bind_address:]port "
|
|
"Cancel remote forward");
|
|
logit(" -KD[bind_address:]port "
|
|
"Cancel dynamic forward");
|
|
if (!options.permit_local_command)
|
|
goto out;
|
|
logit(" !args "
|
|
"Execute local command");
|
|
goto out;
|
|
}
|
|
|
|
if (*s == '!' && options.permit_local_command) {
|
|
s++;
|
|
ssh_local_cmd(s);
|
|
goto out;
|
|
}
|
|
|
|
if (*s == 'K') {
|
|
delete = 1;
|
|
s++;
|
|
}
|
|
if (*s == 'L')
|
|
local = 1;
|
|
else if (*s == 'R')
|
|
remote = 1;
|
|
else if (*s == 'D')
|
|
dynamic = 1;
|
|
else {
|
|
logit("Invalid command.");
|
|
goto out;
|
|
}
|
|
|
|
if (delete && !compat20) {
|
|
logit("Not supported for SSH protocol version 1.");
|
|
goto out;
|
|
}
|
|
|
|
while (isspace(*++s))
|
|
;
|
|
|
|
/* XXX update list of forwards in options */
|
|
if (delete) {
|
|
cancel_port = 0;
|
|
cancel_host = hpdelim(&s); /* may be NULL */
|
|
if (s != NULL) {
|
|
cancel_port = a2port(s);
|
|
cancel_host = cleanhostname(cancel_host);
|
|
} else {
|
|
cancel_port = a2port(cancel_host);
|
|
cancel_host = NULL;
|
|
}
|
|
if (cancel_port <= 0) {
|
|
logit("Bad forwarding close port");
|
|
goto out;
|
|
}
|
|
if (remote)
|
|
ok = channel_request_rforward_cancel(cancel_host,
|
|
cancel_port) == 0;
|
|
else if (dynamic)
|
|
ok = channel_cancel_lport_listener(cancel_host,
|
|
cancel_port, 0, options.gateway_ports) > 0;
|
|
else
|
|
ok = channel_cancel_lport_listener(cancel_host,
|
|
cancel_port, CHANNEL_CANCEL_PORT_STATIC,
|
|
options.gateway_ports) > 0;
|
|
if (!ok) {
|
|
logit("Unkown port forwarding.");
|
|
goto out;
|
|
}
|
|
logit("Canceled forwarding.");
|
|
} else {
|
|
if (!parse_forward(&fwd, s, dynamic, remote)) {
|
|
logit("Bad forwarding specification.");
|
|
goto out;
|
|
}
|
|
if (local || dynamic) {
|
|
if (!channel_setup_local_fwd_listener(fwd.listen_host,
|
|
fwd.listen_port, fwd.connect_host,
|
|
fwd.connect_port, options.gateway_ports)) {
|
|
logit("Port forwarding failed.");
|
|
goto out;
|
|
}
|
|
} else {
|
|
if (channel_request_remote_forwarding(fwd.listen_host,
|
|
fwd.listen_port, fwd.connect_host,
|
|
fwd.connect_port) < 0) {
|
|
logit("Port forwarding failed.");
|
|
goto out;
|
|
}
|
|
}
|
|
logit("Forwarding port.");
|
|
}
|
|
|
|
out:
|
|
signal(SIGINT, handler);
|
|
enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
if (cmd)
|
|
xfree(cmd);
|
|
if (fwd.listen_host != NULL)
|
|
xfree(fwd.listen_host);
|
|
if (fwd.connect_host != NULL)
|
|
xfree(fwd.connect_host);
|
|
}
|
|
|
|
/* reasons to suppress output of an escape command in help output */
|
|
#define SUPPRESS_NEVER 0 /* never suppress, always show */
|
|
#define SUPPRESS_PROTO1 1 /* don't show in protocol 1 sessions */
|
|
#define SUPPRESS_MUXCLIENT 2 /* don't show in mux client sessions */
|
|
#define SUPPRESS_MUXMASTER 4 /* don't show in mux master sessions */
|
|
#define SUPPRESS_SYSLOG 8 /* don't show when logging to syslog */
|
|
struct escape_help_text {
|
|
const char *cmd;
|
|
const char *text;
|
|
unsigned int flags;
|
|
};
|
|
static struct escape_help_text esc_txt[] = {
|
|
{".", "terminate session", SUPPRESS_MUXMASTER},
|
|
{".", "terminate connection (and any multiplexed sessions)",
|
|
SUPPRESS_MUXCLIENT},
|
|
{"B", "send a BREAK to the remote system", SUPPRESS_PROTO1},
|
|
{"C", "open a command line", SUPPRESS_MUXCLIENT},
|
|
{"R", "request rekey", SUPPRESS_PROTO1},
|
|
{"V/v", "decrease/increase verbosity (LogLevel)", SUPPRESS_MUXCLIENT},
|
|
{"^Z", "suspend ssh", SUPPRESS_MUXCLIENT},
|
|
{"#", "list forwarded connections", SUPPRESS_NEVER},
|
|
{"&", "background ssh (when waiting for connections to terminate)",
|
|
SUPPRESS_MUXCLIENT},
|
|
{"?", "this message", SUPPRESS_NEVER},
|
|
};
|
|
|
|
static void
|
|
print_escape_help(Buffer *b, int escape_char, int protocol2, int mux_client,
|
|
int using_stderr)
|
|
{
|
|
unsigned int i, suppress_flags;
|
|
char string[1024];
|
|
|
|
snprintf(string, sizeof string, "%c?\r\n"
|
|
"Supported escape sequences:\r\n", escape_char);
|
|
buffer_append(b, string, strlen(string));
|
|
|
|
suppress_flags = (protocol2 ? 0 : SUPPRESS_PROTO1) |
|
|
(mux_client ? SUPPRESS_MUXCLIENT : 0) |
|
|
(mux_client ? 0 : SUPPRESS_MUXMASTER) |
|
|
(using_stderr ? 0 : SUPPRESS_SYSLOG);
|
|
|
|
for (i = 0; i < sizeof(esc_txt)/sizeof(esc_txt[0]); i++) {
|
|
if (esc_txt[i].flags & suppress_flags)
|
|
continue;
|
|
snprintf(string, sizeof string, " %c%-3s - %s\r\n",
|
|
escape_char, esc_txt[i].cmd, esc_txt[i].text);
|
|
buffer_append(b, string, strlen(string));
|
|
}
|
|
|
|
snprintf(string, sizeof string,
|
|
" %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);
|
|
buffer_append(b, string, strlen(string));
|
|
}
|
|
|
|
/*
|
|
* Process the characters one by one, call with c==NULL for proto1 case.
|
|
*/
|
|
static int
|
|
process_escapes(Channel *c, 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;
|
|
int *escape_pendingp, escape_char;
|
|
struct escape_filter_ctx *efc;
|
|
|
|
if (c == NULL) {
|
|
escape_pendingp = &escape_pending1;
|
|
escape_char = escape_char1;
|
|
} else {
|
|
if (c->filter_ctx == NULL)
|
|
return 0;
|
|
efc = (struct escape_filter_ctx *)c->filter_ctx;
|
|
escape_pendingp = &efc->escape_pending;
|
|
escape_char = efc->escape_char;
|
|
}
|
|
|
|
if (len <= 0)
|
|
return (0);
|
|
|
|
for (i = 0; i < (u_int)len; i++) {
|
|
/* Get one character at a time. */
|
|
ch = buf[i];
|
|
|
|
if (*escape_pendingp) {
|
|
/* We have previously seen an escape character. */
|
|
/* Clear the flag now. */
|
|
*escape_pendingp = 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));
|
|
|
|
if (c && c->ctl_chan != -1) {
|
|
chan_read_failed(c);
|
|
chan_write_failed(c);
|
|
mux_master_session_cleanup_cb(c->self,
|
|
NULL);
|
|
return 0;
|
|
} else
|
|
quit_pending = 1;
|
|
return -1;
|
|
|
|
case 'Z' - 64:
|
|
/* XXX support this for mux clients */
|
|
if (c && c->ctl_chan != -1) {
|
|
char b[16];
|
|
noescape:
|
|
if (ch == 'Z' - 64)
|
|
snprintf(b, sizeof b, "^Z");
|
|
else
|
|
snprintf(b, sizeof b, "%c", ch);
|
|
snprintf(string, sizeof string,
|
|
"%c%s escape not available to "
|
|
"multiplexed sessions\r\n",
|
|
escape_char, b);
|
|
buffer_append(berr, string,
|
|
strlen(string));
|
|
continue;
|
|
}
|
|
/* Suspend the program. Inform 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 'V':
|
|
/* FALLTHROUGH */
|
|
case 'v':
|
|
if (c && c->ctl_chan != -1)
|
|
goto noescape;
|
|
if (!log_is_on_stderr()) {
|
|
snprintf(string, sizeof string,
|
|
"%c%c [Logging to syslog]\r\n",
|
|
escape_char, ch);
|
|
buffer_append(berr, string,
|
|
strlen(string));
|
|
continue;
|
|
}
|
|
if (ch == 'V' && options.log_level >
|
|
SYSLOG_LEVEL_QUIET)
|
|
log_change_level(--options.log_level);
|
|
if (ch == 'v' && options.log_level <
|
|
SYSLOG_LEVEL_DEBUG3)
|
|
log_change_level(++options.log_level);
|
|
snprintf(string, sizeof string,
|
|
"%c%c [LogLevel %s]\r\n", escape_char, ch,
|
|
log_level_name(options.log_level));
|
|
buffer_append(berr, string, strlen(string));
|
|
continue;
|
|
|
|
case '&':
|
|
if (c && c->ctl_chan != -1)
|
|
goto noescape;
|
|
/*
|
|
* Detach the program (continue to serve
|
|
* connections, but put in background and no
|
|
* more new connections).
|
|
*/
|
|
/* Restore tty modes. */
|
|
leave_raw_mode(
|
|
options.request_tty == REQUEST_TTY_FORCE);
|
|
|
|
/* 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 '?':
|
|
print_escape_help(berr, escape_char, compat20,
|
|
(c && c->ctl_chan != -1),
|
|
log_is_on_stderr());
|
|
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':
|
|
if (c && c->ctl_chan != -1)
|
|
goto noescape;
|
|
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_pendingp = 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;
|
|
}
|
|
|
|
static void
|
|
client_process_input(fd_set *readset)
|
|
{
|
|
int len;
|
|
char buf[SSH_IOBUFSZ];
|
|
|
|
/* 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 &&
|
|
(errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
|
|
return; /* we'll try again later */
|
|
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));
|
|
}
|
|
/* 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_char1 == SSH_ESCAPECHAR_NONE) {
|
|
/*
|
|
* Normal successful read, and no escape character.
|
|
* Just append the data to buffer.
|
|
*/
|
|
buffer_append(&stdin_buffer, buf, len);
|
|
} else {
|
|
/*
|
|
* Normal, successful read. But we have an escape
|
|
* character and have to process the characters one
|
|
* by one.
|
|
*/
|
|
if (process_escapes(NULL, &stdin_buffer,
|
|
&stdout_buffer, &stderr_buffer, buf, len) == -1)
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
static 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 == EINTR || errno == EAGAIN ||
|
|
errno == EWOULDBLOCK)
|
|
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));
|
|
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 == EINTR || errno == EAGAIN ||
|
|
errno == EWOULDBLOCK)
|
|
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.
|
|
*/
|
|
|
|
static void
|
|
client_process_buffered_input_packets(void)
|
|
{
|
|
dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
|
|
compat20 ? xxx_kex : NULL);
|
|
}
|
|
|
|
/* scan buf[] for '~' before sending data to the peer */
|
|
|
|
/* Helper: allocate a new escape_filter_ctx and fill in its escape char */
|
|
void *
|
|
client_new_escape_filter_ctx(int escape_char)
|
|
{
|
|
struct escape_filter_ctx *ret;
|
|
|
|
ret = xmalloc(sizeof(*ret));
|
|
ret->escape_pending = 0;
|
|
ret->escape_char = escape_char;
|
|
return (void *)ret;
|
|
}
|
|
|
|
/* Free the escape filter context on channel free */
|
|
void
|
|
client_filter_cleanup(int cid, void *ctx)
|
|
{
|
|
xfree(ctx);
|
|
}
|
|
|
|
int
|
|
client_simple_escape_filter(Channel *c, char *buf, int len)
|
|
{
|
|
if (c->extended_usage != CHAN_EXTENDED_WRITE)
|
|
return 0;
|
|
|
|
return process_escapes(c, &c->input, &c->output, &c->extended,
|
|
buf, len);
|
|
}
|
|
|
|
static void
|
|
client_channel_closed(int id, void *arg)
|
|
{
|
|
channel_cancel_cleanup(id);
|
|
session_closed = 1;
|
|
leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
}
|
|
|
|
/*
|
|
* 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 != SSH_ESCAPECHAR_NONE, 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)
|
|
{
|
|
fd_set *readset = NULL, *writeset = NULL;
|
|
double start_time, total_time;
|
|
int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
|
|
u_int64_t ibytes, obytes;
|
|
u_int nalloc = 0;
|
|
char buf[100];
|
|
|
|
debug("Entering interactive session.");
|
|
|
|
start_time = get_current_time();
|
|
|
|
/* Initialize variables. */
|
|
escape_pending1 = 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 = MAX(connection_in, connection_out);
|
|
|
|
if (!compat20) {
|
|
/* enable nonblocking unless tty */
|
|
if (!isatty(fileno(stdin)))
|
|
set_nonblock(fileno(stdin));
|
|
if (!isatty(fileno(stdout)))
|
|
set_nonblock(fileno(stdout));
|
|
if (!isatty(fileno(stderr)))
|
|
set_nonblock(fileno(stderr));
|
|
max_fd = MAX(max_fd, fileno(stdin));
|
|
max_fd = MAX(max_fd, fileno(stdout));
|
|
max_fd = MAX(max_fd, fileno(stderr));
|
|
}
|
|
quit_pending = 0;
|
|
escape_char1 = escape_char_arg;
|
|
|
|
/* Initialize buffers. */
|
|
buffer_init(&stdin_buffer);
|
|
buffer_init(&stdout_buffer);
|
|
buffer_init(&stderr_buffer);
|
|
|
|
client_init_dispatch();
|
|
|
|
/*
|
|
* Set signal handlers, (e.g. to restore non-blocking mode)
|
|
* but don't overwrite SIG_IGN, matches behaviour from rsh(1)
|
|
*/
|
|
if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
|
|
signal(SIGHUP, signal_handler);
|
|
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
|
|
signal(SIGINT, signal_handler);
|
|
if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
|
|
signal(SIGQUIT, signal_handler);
|
|
if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
|
|
signal(SIGTERM, signal_handler);
|
|
signal(SIGWINCH, window_change_handler);
|
|
|
|
if (have_pty)
|
|
enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
|
|
if (compat20) {
|
|
session_ident = ssh2_chan_id;
|
|
if (session_ident != -1) {
|
|
if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
|
|
channel_register_filter(session_ident,
|
|
client_simple_escape_filter, NULL,
|
|
client_filter_cleanup,
|
|
client_new_escape_filter_ctx(
|
|
escape_char_arg));
|
|
}
|
|
channel_register_cleanup(session_ident,
|
|
client_channel_closed, 0);
|
|
}
|
|
} else {
|
|
/* Check if we should immediately send eof on stdin. */
|
|
client_check_initial_eof_on_stdin();
|
|
}
|
|
|
|
/* Main loop of the client for the interactive session mode. */
|
|
while (!quit_pending) {
|
|
|
|
/* Process buffered packets sent by the server. */
|
|
client_process_buffered_input_packets();
|
|
|
|
if (compat20 && session_closed && !channel_still_open())
|
|
break;
|
|
|
|
rekeying = (xxx_kex != NULL && !xxx_kex->done);
|
|
|
|
if (rekeying) {
|
|
debug("rekeying in progress");
|
|
} else {
|
|
/*
|
|
* 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
|
|
* enqueue 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).
|
|
*/
|
|
max_fd2 = max_fd;
|
|
client_wait_until_can_do_something(&readset, &writeset,
|
|
&max_fd2, &nalloc, rekeying);
|
|
|
|
if (quit_pending)
|
|
break;
|
|
|
|
/* Do channel operations unless rekeying in progress. */
|
|
if (!rekeying) {
|
|
channel_after_select(readset, writeset);
|
|
if (need_rekeying || packet_need_rekeying()) {
|
|
debug("need rekeying");
|
|
xxx_kex->done = 0;
|
|
kex_send_kexinit(xxx_kex);
|
|
need_rekeying = 0;
|
|
}
|
|
}
|
|
|
|
/* 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);
|
|
}
|
|
|
|
if (session_resumed) {
|
|
connection_in = packet_get_connection_in();
|
|
connection_out = packet_get_connection_out();
|
|
max_fd = MAX(max_fd, connection_out);
|
|
max_fd = MAX(max_fd, connection_in);
|
|
session_resumed = 0;
|
|
}
|
|
|
|
/*
|
|
* Send as much buffered packet data as possible to the
|
|
* sender.
|
|
*/
|
|
if (FD_ISSET(connection_out, writeset))
|
|
packet_write_poll();
|
|
|
|
/*
|
|
* If we are a backgrounded control master, and the
|
|
* timeout has expired without any active client
|
|
* connections, then quit.
|
|
*/
|
|
if (control_persist_exit_time > 0) {
|
|
if (time(NULL) >= control_persist_exit_time) {
|
|
debug("ControlPersist timeout expired");
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (readset)
|
|
xfree(readset);
|
|
if (writeset)
|
|
xfree(writeset);
|
|
|
|
/* Terminate the session. */
|
|
|
|
/* Stop watching for window change. */
|
|
signal(SIGWINCH, SIG_DFL);
|
|
|
|
if (compat20) {
|
|
packet_start(SSH2_MSG_DISCONNECT);
|
|
packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
|
|
packet_put_cstring("disconnected by user");
|
|
packet_put_cstring(""); /* language tag */
|
|
packet_send();
|
|
packet_write_wait();
|
|
}
|
|
|
|
channel_free_all();
|
|
|
|
if (have_pty)
|
|
leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
|
|
/* restore blocking io */
|
|
if (!isatty(fileno(stdin)))
|
|
unset_nonblock(fileno(stdin));
|
|
if (!isatty(fileno(stdout)))
|
|
unset_nonblock(fileno(stdout));
|
|
if (!isatty(fileno(stderr)))
|
|
unset_nonblock(fileno(stderr));
|
|
|
|
/*
|
|
* If there was no shell or command requested, there will be no remote
|
|
* exit status to be returned. In that case, clear error code if the
|
|
* connection was deliberately terminated at this end.
|
|
*/
|
|
if (no_shell_flag && received_signal == SIGTERM) {
|
|
received_signal = 0;
|
|
exit_status = 0;
|
|
}
|
|
|
|
if (received_signal)
|
|
fatal("Killed by signal %d.", (int) received_signal);
|
|
|
|
/*
|
|
* 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. */
|
|
if (buffer_len(&stdout_buffer) > 0) {
|
|
len = atomicio(vwrite, fileno(stdout),
|
|
buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
|
|
if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
|
|
error("Write failed flushing stdout buffer.");
|
|
else
|
|
buffer_consume(&stdout_buffer, len);
|
|
}
|
|
|
|
/* Output any buffered data for stderr. */
|
|
if (buffer_len(&stderr_buffer) > 0) {
|
|
len = atomicio(vwrite, fileno(stderr),
|
|
buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
|
|
if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
|
|
error("Write failed flushing stderr buffer.");
|
|
else
|
|
buffer_consume(&stderr_buffer, len);
|
|
}
|
|
|
|
/* 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;
|
|
packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
|
|
packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
|
|
verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
|
|
(unsigned long long)obytes, (unsigned long long)ibytes, total_time);
|
|
if (total_time > 0)
|
|
verbose("Bytes per second: sent %.1f, received %.1f",
|
|
obytes / total_time, ibytes / total_time);
|
|
/* Return the exit status of the program. */
|
|
debug("Exit status %d", exit_status);
|
|
return exit_status;
|
|
}
|
|
|
|
/*********/
|
|
|
|
static void
|
|
client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
u_int data_len;
|
|
char *data = packet_get_string(&data_len);
|
|
packet_check_eom();
|
|
buffer_append(&stdout_buffer, data, data_len);
|
|
memset(data, 0, data_len);
|
|
xfree(data);
|
|
}
|
|
static void
|
|
client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
u_int data_len;
|
|
char *data = packet_get_string(&data_len);
|
|
packet_check_eom();
|
|
buffer_append(&stderr_buffer, data, data_len);
|
|
memset(data, 0, data_len);
|
|
xfree(data);
|
|
}
|
|
static void
|
|
client_input_exit_status(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
exit_status = packet_get_int();
|
|
packet_check_eom();
|
|
/* 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;
|
|
}
|
|
static void
|
|
client_input_agent_open(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
Channel *c = NULL;
|
|
int remote_id, sock;
|
|
|
|
/* Read the remote channel number from the message. */
|
|
remote_id = packet_get_int();
|
|
packet_check_eom();
|
|
|
|
/*
|
|
* Get a connection to the local authentication agent (this may again
|
|
* get forwarded).
|
|
*/
|
|
sock = ssh_get_authentication_socket();
|
|
|
|
/*
|
|
* If we could not connect the agent, send an error message back to
|
|
* the server. This should never happen unless the agent dies,
|
|
* because authentication forwarding is only enabled if we have an
|
|
* agent.
|
|
*/
|
|
if (sock >= 0) {
|
|
c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
|
|
-1, 0, 0, 0, "authentication agent connection", 1);
|
|
c->remote_id = remote_id;
|
|
c->force_drain = 1;
|
|
}
|
|
if (c == NULL) {
|
|
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
|
|
packet_put_int(remote_id);
|
|
} else {
|
|
/* Send a confirmation to the remote host. */
|
|
debug("Forwarding authentication connection.");
|
|
packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
|
|
packet_put_int(remote_id);
|
|
packet_put_int(c->self);
|
|
}
|
|
packet_send();
|
|
}
|
|
|
|
static Channel *
|
|
client_request_forwarded_tcpip(const char *request_type, int rchan)
|
|
{
|
|
Channel *c = NULL;
|
|
char *listen_address, *originator_address;
|
|
u_short listen_port, originator_port;
|
|
|
|
/* Get rest of the packet */
|
|
listen_address = packet_get_string(NULL);
|
|
listen_port = packet_get_int();
|
|
originator_address = packet_get_string(NULL);
|
|
originator_port = packet_get_int();
|
|
packet_check_eom();
|
|
|
|
debug("client_request_forwarded_tcpip: listen %s port %d, "
|
|
"originator %s port %d", listen_address, listen_port,
|
|
originator_address, originator_port);
|
|
|
|
c = channel_connect_by_listen_address(listen_port,
|
|
"forwarded-tcpip", originator_address);
|
|
|
|
xfree(originator_address);
|
|
xfree(listen_address);
|
|
return c;
|
|
}
|
|
|
|
static Channel *
|
|
client_request_x11(const char *request_type, int rchan)
|
|
{
|
|
Channel *c = NULL;
|
|
char *originator;
|
|
u_short originator_port;
|
|
int sock;
|
|
|
|
if (!options.forward_x11) {
|
|
error("Warning: ssh server tried X11 forwarding.");
|
|
error("Warning: this is probably a break-in attempt by a "
|
|
"malicious server.");
|
|
return NULL;
|
|
}
|
|
if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
|
|
verbose("Rejected X11 connection after ForwardX11Timeout "
|
|
"expired");
|
|
return NULL;
|
|
}
|
|
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_check_eom();
|
|
/* XXX check permission */
|
|
debug("client_request_x11: request from %s %d", originator,
|
|
originator_port);
|
|
xfree(originator);
|
|
sock = x11_connect_display();
|
|
if (sock < 0)
|
|
return NULL;
|
|
c = channel_new("x11",
|
|
SSH_CHANNEL_X11_OPEN, sock, sock, -1,
|
|
CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
|
|
c->force_drain = 1;
|
|
return c;
|
|
}
|
|
|
|
static Channel *
|
|
client_request_agent(const char *request_type, int rchan)
|
|
{
|
|
Channel *c = NULL;
|
|
int sock;
|
|
|
|
if (!options.forward_agent) {
|
|
error("Warning: ssh server tried agent forwarding.");
|
|
error("Warning: this is probably a break-in attempt by a "
|
|
"malicious server.");
|
|
return NULL;
|
|
}
|
|
sock = ssh_get_authentication_socket();
|
|
if (sock < 0)
|
|
return NULL;
|
|
c = channel_new("authentication agent connection",
|
|
SSH_CHANNEL_OPEN, sock, sock, -1,
|
|
CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
|
|
"authentication agent connection", 1);
|
|
c->force_drain = 1;
|
|
return c;
|
|
}
|
|
|
|
int
|
|
client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
|
|
{
|
|
Channel *c;
|
|
int fd;
|
|
|
|
if (tun_mode == SSH_TUNMODE_NO)
|
|
return 0;
|
|
|
|
if (!compat20) {
|
|
error("Tunnel forwarding is not supported for protocol 1");
|
|
return -1;
|
|
}
|
|
|
|
debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
|
|
|
|
/* Open local tunnel device */
|
|
if ((fd = tun_open(local_tun, tun_mode)) == -1) {
|
|
error("Tunnel device open failed.");
|
|
return -1;
|
|
}
|
|
|
|
c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
|
|
CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
|
|
c->datagram = 1;
|
|
|
|
#if defined(SSH_TUN_FILTER)
|
|
if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
|
|
channel_register_filter(c->self, sys_tun_infilter,
|
|
sys_tun_outfilter, NULL, NULL);
|
|
#endif
|
|
|
|
packet_start(SSH2_MSG_CHANNEL_OPEN);
|
|
packet_put_cstring("tun@openssh.com");
|
|
packet_put_int(c->self);
|
|
packet_put_int(c->local_window_max);
|
|
packet_put_int(c->local_maxpacket);
|
|
packet_put_int(tun_mode);
|
|
packet_put_int(remote_tun);
|
|
packet_send();
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* XXXX move to generic input handler */
|
|
static void
|
|
client_input_channel_open(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
Channel *c = NULL;
|
|
char *ctype;
|
|
int rchan;
|
|
u_int rmaxpack, rwindow, len;
|
|
|
|
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, "forwarded-tcpip") == 0) {
|
|
c = client_request_forwarded_tcpip(ctype, rchan);
|
|
} else if (strcmp(ctype, "x11") == 0) {
|
|
c = client_request_x11(ctype, rchan);
|
|
} else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
|
|
c = client_request_agent(ctype, rchan);
|
|
}
|
|
/* XXX duplicate : */
|
|
if (c != NULL) {
|
|
debug("confirm %s", ctype);
|
|
c->remote_id = rchan;
|
|
c->remote_window = rwindow;
|
|
c->remote_maxpacket = rmaxpack;
|
|
if (c->type != SSH_CHANNEL_CONNECTING) {
|
|
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);
|
|
if (!(datafellows & SSH_BUG_OPENFAILURE)) {
|
|
packet_put_cstring("open failed");
|
|
packet_put_cstring("");
|
|
}
|
|
packet_send();
|
|
}
|
|
xfree(ctype);
|
|
}
|
|
static void
|
|
client_input_channel_req(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
Channel *c = NULL;
|
|
int exitval, id, reply, success = 0;
|
|
char *rtype;
|
|
|
|
id = packet_get_int();
|
|
rtype = packet_get_string(NULL);
|
|
reply = packet_get_char();
|
|
|
|
debug("client_input_channel_req: channel %d rtype %s reply %d",
|
|
id, rtype, reply);
|
|
|
|
if (id == -1) {
|
|
error("client_input_channel_req: request for channel -1");
|
|
} else if ((c = channel_lookup(id)) == NULL) {
|
|
error("client_input_channel_req: channel %d: "
|
|
"unknown channel", id);
|
|
} else if (strcmp(rtype, "eow@openssh.com") == 0) {
|
|
packet_check_eom();
|
|
chan_rcvd_eow(c);
|
|
} else if (strcmp(rtype, "exit-status") == 0) {
|
|
exitval = packet_get_int();
|
|
if (c->ctl_chan != -1) {
|
|
mux_exit_message(c, exitval);
|
|
success = 1;
|
|
} else if (id == session_ident) {
|
|
/* Record exit value of local session */
|
|
success = 1;
|
|
exit_status = exitval;
|
|
} else {
|
|
/* Probably for a mux channel that has already closed */
|
|
debug("%s: no sink for exit-status on channel %d",
|
|
__func__, id);
|
|
}
|
|
packet_check_eom();
|
|
}
|
|
if (reply && c != NULL) {
|
|
packet_start(success ?
|
|
SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
|
|
packet_put_int(c->remote_id);
|
|
packet_send();
|
|
}
|
|
xfree(rtype);
|
|
}
|
|
static void
|
|
client_input_global_request(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
char *rtype;
|
|
int want_reply;
|
|
int success = 0;
|
|
|
|
rtype = packet_get_string(NULL);
|
|
want_reply = packet_get_char();
|
|
debug("client_input_global_request: rtype %s want_reply %d",
|
|
rtype, want_reply);
|
|
if (want_reply) {
|
|
packet_start(success ?
|
|
SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
|
|
packet_send();
|
|
packet_write_wait();
|
|
}
|
|
xfree(rtype);
|
|
}
|
|
|
|
void
|
|
client_session2_setup(int id, int want_tty, int want_subsystem,
|
|
const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
|
|
{
|
|
int len;
|
|
Channel *c = NULL;
|
|
|
|
debug2("%s: id %d", __func__, id);
|
|
|
|
if ((c = channel_lookup(id)) == NULL)
|
|
fatal("client_session2_setup: channel %d: unknown channel", id);
|
|
|
|
packet_set_interactive(want_tty,
|
|
options.ip_qos_interactive, options.ip_qos_bulk);
|
|
|
|
if (want_tty) {
|
|
struct winsize ws;
|
|
|
|
/* Store window size in the packet. */
|
|
if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
|
|
memset(&ws, 0, sizeof(ws));
|
|
|
|
channel_request_start(id, "pty-req", 1);
|
|
client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
|
|
packet_put_cstring(term != NULL ? term : "");
|
|
packet_put_int((u_int)ws.ws_col);
|
|
packet_put_int((u_int)ws.ws_row);
|
|
packet_put_int((u_int)ws.ws_xpixel);
|
|
packet_put_int((u_int)ws.ws_ypixel);
|
|
if (tiop == NULL)
|
|
tiop = get_saved_tio();
|
|
tty_make_modes(-1, tiop);
|
|
packet_send();
|
|
/* XXX wait for reply */
|
|
c->client_tty = 1;
|
|
}
|
|
|
|
/* Transfer any environment variables from client to server */
|
|
if (options.num_send_env != 0 && env != NULL) {
|
|
int i, j, matched;
|
|
char *name, *val;
|
|
|
|
debug("Sending environment.");
|
|
for (i = 0; env[i] != NULL; i++) {
|
|
/* Split */
|
|
name = xstrdup(env[i]);
|
|
if ((val = strchr(name, '=')) == NULL) {
|
|
xfree(name);
|
|
continue;
|
|
}
|
|
*val++ = '\0';
|
|
|
|
matched = 0;
|
|
for (j = 0; j < options.num_send_env; j++) {
|
|
if (match_pattern(name, options.send_env[j])) {
|
|
matched = 1;
|
|
break;
|
|
}
|
|
}
|
|
if (!matched) {
|
|
debug3("Ignored env %s", name);
|
|
xfree(name);
|
|
continue;
|
|
}
|
|
|
|
debug("Sending env %s = %s", name, val);
|
|
channel_request_start(id, "env", 0);
|
|
packet_put_cstring(name);
|
|
packet_put_cstring(val);
|
|
packet_send();
|
|
xfree(name);
|
|
}
|
|
}
|
|
|
|
len = buffer_len(cmd);
|
|
if (len > 0) {
|
|
if (len > 900)
|
|
len = 900;
|
|
if (want_subsystem) {
|
|
debug("Sending subsystem: %.*s",
|
|
len, (u_char*)buffer_ptr(cmd));
|
|
channel_request_start(id, "subsystem", 1);
|
|
client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
|
|
} else {
|
|
debug("Sending command: %.*s",
|
|
len, (u_char*)buffer_ptr(cmd));
|
|
channel_request_start(id, "exec", 1);
|
|
client_expect_confirm(id, "exec", CONFIRM_CLOSE);
|
|
}
|
|
packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
|
|
packet_send();
|
|
} else {
|
|
channel_request_start(id, "shell", 1);
|
|
client_expect_confirm(id, "shell", CONFIRM_CLOSE);
|
|
packet_send();
|
|
}
|
|
}
|
|
|
|
static void
|
|
client_init_dispatch_20(void)
|
|
{
|
|
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, &client_input_channel_req);
|
|
dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
|
|
dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
|
|
dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
|
|
dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
|
|
|
|
/* rekeying */
|
|
dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
|
|
|
|
/* global request reply messages */
|
|
dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
|
|
dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
|
|
}
|
|
|
|
static void
|
|
client_init_dispatch_13(void)
|
|
{
|
|
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 ?
|
|
&client_input_agent_open : &deny_input_open);
|
|
dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
|
|
&x11_input_open : &deny_input_open);
|
|
}
|
|
|
|
static void
|
|
client_init_dispatch_15(void)
|
|
{
|
|
client_init_dispatch_13();
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
|
|
}
|
|
|
|
static void
|
|
client_init_dispatch(void)
|
|
{
|
|
if (compat20)
|
|
client_init_dispatch_20();
|
|
else if (compat13)
|
|
client_init_dispatch_13();
|
|
else
|
|
client_init_dispatch_15();
|
|
}
|
|
|
|
void
|
|
client_stop_mux(void)
|
|
{
|
|
if (options.control_path != NULL && muxserver_sock != -1)
|
|
unlink(options.control_path);
|
|
/*
|
|
* If we are in persist mode, or don't have a shell, signal that we
|
|
* should close when all active channels are closed.
|
|
*/
|
|
if (options.control_persist || no_shell_flag) {
|
|
session_closed = 1;
|
|
setproctitle("[stopped mux]");
|
|
}
|
|
}
|
|
|
|
/* client specific fatal cleanup */
|
|
void
|
|
cleanup_exit(int i)
|
|
{
|
|
leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
|
|
leave_non_blocking();
|
|
if (options.control_path != NULL && muxserver_sock != -1)
|
|
unlink(options.control_path);
|
|
ssh_kill_proxy_command();
|
|
_exit(i);
|
|
}
|