/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Server main loop for handling the interactive session.
*
* 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".
*
* SSH2 support by Markus Friedl.
* Copyright (c) 2000, 2001 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("$OpenBSD: serverloop.c,v 1.106 2003/04/01 10:22:21 markus Exp $");
#include "xmalloc.h"
#include "packet.h"
#include "buffer.h"
#include "log.h"
#include "servconf.h"
#include "canohost.h"
#include "sshpty.h"
#include "channels.h"
#include "compat.h"
#include "ssh1.h"
#include "ssh2.h"
#include "auth.h"
#include "session.h"
#include "dispatch.h"
#include "auth-options.h"
#include "serverloop.h"
#include "misc.h"
#include "kex.h"
extern ServerOptions options;
/* XXX */
extern Kex *xxx_kex;
static Authctxt *xxx_authctxt;
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 int fdin; /* Descriptor for stdin (for writing) */
static int fdout; /* Descriptor for stdout (for reading);
May be same number as fdin. */
static int fderr; /* Descriptor for stderr. May be -1. */
static long stdin_bytes = 0; /* Number of bytes written to stdin. */
static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */
static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */
static long fdout_bytes = 0; /* Number of stdout bytes read from program. */
static int stdin_eof = 0; /* EOF message received from client. */
static int fdout_eof = 0; /* EOF encountered reading from fdout. */
static int fderr_eof = 0; /* EOF encountered readung from fderr. */
static int fdin_is_tty = 0; /* fdin points to a tty. */
static int connection_in; /* Connection to client (input). */
static int connection_out; /* Connection to client (output). */
static int connection_closed = 0; /* Connection to client closed. */
static u_int buffer_high; /* "Soft" max buffer size. */
static int client_alive_timeouts = 0;
/*
* This SIGCHLD kludge is used to detect when the child exits. The server
* will exit after that, as soon as forwarded connections have terminated.
*/
static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */
/* prototypes */
static void server_init_dispatch(void);
/*
* we write to this pipe if a SIGCHLD is caught in order to avoid
* the race between select() and child_terminated
*/
static int notify_pipe[2];
static void
notify_setup(void)
{
if (pipe(notify_pipe) < 0) {
error("pipe(notify_pipe) failed %s", strerror(errno));
} else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) ||
(fcntl(notify_pipe[1], F_SETFD, 1) == -1)) {
error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno));
close(notify_pipe[0]);
close(notify_pipe[1]);
} else {
set_nonblock(notify_pipe[0]);
set_nonblock(notify_pipe[1]);
return;
}
notify_pipe[0] = -1; /* read end */
notify_pipe[1] = -1; /* write end */
}
static void
notify_parent(void)
{
if (notify_pipe[1] != -1)
write(notify_pipe[1], "", 1);
}