869 lines
25 KiB
C
869 lines
25 KiB
C
/*
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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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* Server main loop for handling the interactive session.
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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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* SSH2 support by Markus Friedl.
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* Copyright (c) 2000 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 "xmalloc.h"
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#include "ssh.h"
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#include "packet.h"
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#include "buffer.h"
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#include "servconf.h"
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#include "pty.h"
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#include "channels.h"
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#include "compat.h"
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#include "ssh2.h"
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#include "session.h"
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#include "dispatch.h"
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#include "auth-options.h"
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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 int fdin; /* Descriptor for stdin (for writing) */
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static int fdout; /* Descriptor for stdout (for reading);
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May be same number as fdin. */
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static int fderr; /* Descriptor for stderr. May be -1. */
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static long stdin_bytes = 0; /* Number of bytes written to stdin. */
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static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */
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static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */
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static long fdout_bytes = 0; /* Number of stdout bytes read from program. */
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static int stdin_eof = 0; /* EOF message received from client. */
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static int fdout_eof = 0; /* EOF encountered reading from fdout. */
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static int fderr_eof = 0; /* EOF encountered readung from fderr. */
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static int connection_in; /* Connection to client (input). */
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static int connection_out; /* Connection to client (output). */
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static unsigned int buffer_high;/* "Soft" max buffer size. */
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static int max_fd; /* Max file descriptor number for select(). */
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/*
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* This SIGCHLD kludge is used to detect when the child exits. The server
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* will exit after that, as soon as forwarded connections have terminated.
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*/
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static pid_t child_pid; /* Pid of the child. */
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static volatile int child_terminated; /* The child has terminated. */
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static volatile int child_wait_status; /* Status from wait(). */
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void server_init_dispatch(void);
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void
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sigchld_handler(int sig)
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{
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int save_errno = errno;
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pid_t wait_pid;
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debug("Received SIGCHLD.");
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wait_pid = wait((int *) &child_wait_status);
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if (wait_pid != -1) {
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if (wait_pid != child_pid)
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error("Strange, got SIGCHLD and wait returned pid %d but child is %d",
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wait_pid, child_pid);
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if (WIFEXITED(child_wait_status) ||
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WIFSIGNALED(child_wait_status))
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child_terminated = 1;
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}
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signal(SIGCHLD, sigchld_handler);
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errno = save_errno;
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}
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void
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sigchld_handler2(int sig)
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{
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int save_errno = errno;
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debug("Received SIGCHLD.");
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child_terminated = 1;
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signal(SIGCHLD, sigchld_handler2);
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errno = save_errno;
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}
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/*
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* Make packets from buffered stderr data, and buffer it for sending
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* to the client.
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*/
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void
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make_packets_from_stderr_data()
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{
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int len;
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/* Send buffered stderr data to the client. */
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while (buffer_len(&stderr_buffer) > 0 &&
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packet_not_very_much_data_to_write()) {
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len = buffer_len(&stderr_buffer);
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if (packet_is_interactive()) {
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if (len > 512)
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len = 512;
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} else {
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/* Keep the packets at reasonable size. */
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if (len > packet_get_maxsize())
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len = packet_get_maxsize();
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}
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packet_start(SSH_SMSG_STDERR_DATA);
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packet_put_string(buffer_ptr(&stderr_buffer), len);
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packet_send();
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buffer_consume(&stderr_buffer, len);
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stderr_bytes += len;
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}
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}
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/*
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* Make packets from buffered stdout data, and buffer it for sending to the
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* client.
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*/
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void
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make_packets_from_stdout_data()
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{
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int len;
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/* Send buffered stdout data to the client. */
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while (buffer_len(&stdout_buffer) > 0 &&
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packet_not_very_much_data_to_write()) {
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len = buffer_len(&stdout_buffer);
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if (packet_is_interactive()) {
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if (len > 512)
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len = 512;
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} else {
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/* Keep the packets at reasonable size. */
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if (len > packet_get_maxsize())
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len = packet_get_maxsize();
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}
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packet_start(SSH_SMSG_STDOUT_DATA);
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packet_put_string(buffer_ptr(&stdout_buffer), len);
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packet_send();
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buffer_consume(&stdout_buffer, len);
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stdout_bytes += len;
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}
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}
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/*
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* Sleep in select() until we can do something. This will initialize the
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* select masks. Upon return, the masks will indicate which descriptors
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* have data or can accept data. Optionally, a maximum time can be specified
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* for the duration of the wait (0 = infinite).
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*/
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void
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wait_until_can_do_something(fd_set * readset, fd_set * writeset,
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unsigned int max_time_milliseconds)
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{
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struct timeval tv, *tvp;
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int ret;
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/* When select fails we restart from here. */
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retry_select:
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/* Initialize select() masks. */
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FD_ZERO(readset);
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FD_ZERO(writeset);
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if (compat20) {
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/* wrong: bad condition XXX */
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if (channel_not_very_much_buffered_data())
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FD_SET(connection_in, readset);
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} else {
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/*
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* Read packets from the client unless we have too much
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* buffered stdin or channel data.
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*/
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if (buffer_len(&stdin_buffer) < buffer_high &&
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channel_not_very_much_buffered_data())
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FD_SET(connection_in, readset);
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/*
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* If there is not too much data already buffered going to
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* the client, try to get some more data from the program.
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*/
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if (packet_not_very_much_data_to_write()) {
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if (!fdout_eof)
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FD_SET(fdout, readset);
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if (!fderr_eof)
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FD_SET(fderr, readset);
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}
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/*
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* If we have buffered data, try to write some of that data
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* to the program.
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*/
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if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
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FD_SET(fdin, writeset);
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}
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/* Set masks for channel descriptors. */
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channel_prepare_select(readset, writeset);
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/*
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* If we have buffered packet data going to the client, mark that
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* descriptor.
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*/
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if (packet_have_data_to_write())
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FD_SET(connection_out, writeset);
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/* Update the maximum descriptor number if appropriate. */
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if (channel_max_fd() > max_fd)
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max_fd = channel_max_fd();
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/*
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* If child has terminated and there is enough buffer space to read
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* from it, then read as much as is available and exit.
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*/
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if (child_terminated && packet_not_very_much_data_to_write())
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if (max_time_milliseconds == 0)
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max_time_milliseconds = 100;
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if (max_time_milliseconds == 0)
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tvp = NULL;
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else {
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tv.tv_sec = max_time_milliseconds / 1000;
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tv.tv_usec = 1000 * (max_time_milliseconds % 1000);
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tvp = &tv;
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}
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if (tvp!=NULL)
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debug("tvp!=NULL kid %d mili %d", child_terminated, max_time_milliseconds);
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/* Wait for something to happen, or the timeout to expire. */
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ret = select(max_fd + 1, readset, writeset, NULL, tvp);
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if (ret < 0) {
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if (errno != EINTR)
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error("select: %.100s", strerror(errno));
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else
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goto retry_select;
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}
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}
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/*
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* Processes input from the client and the program. Input data is stored
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* in buffers and processed later.
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*/
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void
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process_input(fd_set * readset)
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{
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int len;
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char buf[16384];
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/* Read and buffer any input data from the client. */
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if (FD_ISSET(connection_in, readset)) {
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len = read(connection_in, buf, sizeof(buf));
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if (len == 0) {
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verbose("Connection closed by remote host.");
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fatal_cleanup();
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} else if (len < 0) {
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if (errno != EINTR && errno != EAGAIN) {
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verbose("Read error from remote host: %.100s", strerror(errno));
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fatal_cleanup();
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}
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} else {
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/* Buffer any received data. */
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packet_process_incoming(buf, len);
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}
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}
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if (compat20)
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return;
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/* Read and buffer any available stdout data from the program. */
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if (!fdout_eof && FD_ISSET(fdout, readset)) {
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len = read(fdout, buf, sizeof(buf));
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if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
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/* do nothing */
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} else if (len <= 0) {
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fdout_eof = 1;
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} else {
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buffer_append(&stdout_buffer, buf, len);
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fdout_bytes += len;
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}
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}
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/* Read and buffer any available stderr data from the program. */
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if (!fderr_eof && FD_ISSET(fderr, readset)) {
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len = read(fderr, buf, sizeof(buf));
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if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
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/* do nothing */
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} else if (len <= 0) {
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fderr_eof = 1;
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} else {
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buffer_append(&stderr_buffer, buf, len);
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}
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}
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}
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/*
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* Sends data from internal buffers to client program stdin.
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*/
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void
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process_output(fd_set * writeset)
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{
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int len;
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/* Write buffered data to program stdin. */
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if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) {
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len = write(fdin, buffer_ptr(&stdin_buffer),
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buffer_len(&stdin_buffer));
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if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
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/* do nothing */
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} else if (len <= 0) {
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#ifdef USE_PIPES
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close(fdin);
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#else
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if (fdin != fdout)
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close(fdin);
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else
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shutdown(fdin, SHUT_WR); /* We will no longer send. */
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#endif
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fdin = -1;
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} else {
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/* Successful write. Consume the data from the buffer. */
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buffer_consume(&stdin_buffer, len);
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/* Update the count of bytes written to the program. */
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stdin_bytes += len;
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}
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}
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/* Send any buffered packet data to the client. */
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if (FD_ISSET(connection_out, writeset))
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packet_write_poll();
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}
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/*
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* Wait until all buffered output has been sent to the client.
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* This is used when the program terminates.
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*/
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void
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drain_output()
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{
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/* Send any buffered stdout data to the client. */
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if (buffer_len(&stdout_buffer) > 0) {
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packet_start(SSH_SMSG_STDOUT_DATA);
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packet_put_string(buffer_ptr(&stdout_buffer),
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buffer_len(&stdout_buffer));
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packet_send();
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/* Update the count of sent bytes. */
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stdout_bytes += buffer_len(&stdout_buffer);
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}
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/* Send any buffered stderr data to the client. */
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if (buffer_len(&stderr_buffer) > 0) {
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packet_start(SSH_SMSG_STDERR_DATA);
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packet_put_string(buffer_ptr(&stderr_buffer),
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buffer_len(&stderr_buffer));
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packet_send();
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/* Update the count of sent bytes. */
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stderr_bytes += buffer_len(&stderr_buffer);
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}
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/* Wait until all buffered data has been written to the client. */
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packet_write_wait();
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}
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void
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process_buffered_input_packets()
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{
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dispatch_run(DISPATCH_NONBLOCK, NULL);
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}
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/*
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* Performs the interactive session. This handles data transmission between
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* the client and the program. Note that the notion of stdin, stdout, and
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* stderr in this function is sort of reversed: this function writes to
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* stdin (of the child program), and reads from stdout and stderr (of the
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* child program).
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*/
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void
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server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
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{
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fd_set readset, writeset;
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int wait_status; /* Status returned by wait(). */
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pid_t wait_pid; /* pid returned by wait(). */
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int waiting_termination = 0; /* Have displayed waiting close message. */
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unsigned int max_time_milliseconds;
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unsigned int previous_stdout_buffer_bytes;
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unsigned int stdout_buffer_bytes;
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int type;
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debug("Entering interactive session.");
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/* Initialize the SIGCHLD kludge. */
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child_pid = pid;
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child_terminated = 0;
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signal(SIGCHLD, sigchld_handler);
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/* Initialize our global variables. */
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fdin = fdin_arg;
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fdout = fdout_arg;
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fderr = fderr_arg;
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/* nonblocking IO */
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set_nonblock(fdin);
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set_nonblock(fdout);
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/* we don't have stderr for interactive terminal sessions, see below */
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if (fderr != -1)
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set_nonblock(fderr);
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connection_in = packet_get_connection_in();
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connection_out = packet_get_connection_out();
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previous_stdout_buffer_bytes = 0;
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|
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/* Set approximate I/O buffer size. */
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if (packet_is_interactive())
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buffer_high = 4096;
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else
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buffer_high = 64 * 1024;
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|
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/* Initialize max_fd to the maximum of the known file descriptors. */
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max_fd = fdin;
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if (fdout > max_fd)
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max_fd = fdout;
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if (fderr != -1 && fderr > max_fd)
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max_fd = fderr;
|
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if (connection_in > max_fd)
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max_fd = connection_in;
|
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if (connection_out > max_fd)
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max_fd = connection_out;
|
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|
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/* Initialize Initialize buffers. */
|
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buffer_init(&stdin_buffer);
|
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buffer_init(&stdout_buffer);
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buffer_init(&stderr_buffer);
|
|
|
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/*
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* If we have no separate fderr (which is the case when we have a pty
|
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* - there we cannot make difference between data sent to stdout and
|
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* stderr), indicate that we have seen an EOF from stderr. This way
|
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* we don\'t need to check the descriptor everywhere.
|
|
*/
|
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if (fderr == -1)
|
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fderr_eof = 1;
|
|
|
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server_init_dispatch();
|
|
|
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/* Main loop of the server for the interactive session mode. */
|
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for (;;) {
|
|
|
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/* Process buffered packets from the client. */
|
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process_buffered_input_packets();
|
|
|
|
/*
|
|
* If we have received eof, and there is no more pending
|
|
* input data, cause a real eof by closing fdin.
|
|
*/
|
|
if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
|
|
#ifdef USE_PIPES
|
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close(fdin);
|
|
#else
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if (fdin != fdout)
|
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close(fdin);
|
|
else
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shutdown(fdin, SHUT_WR); /* We will no longer send. */
|
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#endif
|
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fdin = -1;
|
|
}
|
|
/* Make packets from buffered stderr data to send to the client. */
|
|
make_packets_from_stderr_data();
|
|
|
|
/*
|
|
* Make packets from buffered stdout data to send to the
|
|
* client. If there is very little to send, this arranges to
|
|
* not send them now, but to wait a short while to see if we
|
|
* are getting more data. This is necessary, as some systems
|
|
* wake up readers from a pty after each separate character.
|
|
*/
|
|
max_time_milliseconds = 0;
|
|
stdout_buffer_bytes = buffer_len(&stdout_buffer);
|
|
if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
|
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stdout_buffer_bytes != previous_stdout_buffer_bytes) {
|
|
/* try again after a while */
|
|
max_time_milliseconds = 10;
|
|
} else {
|
|
/* Send it now. */
|
|
make_packets_from_stdout_data();
|
|
}
|
|
previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);
|
|
|
|
/* Send channel data to the client. */
|
|
if (packet_not_very_much_data_to_write())
|
|
channel_output_poll();
|
|
|
|
/*
|
|
* Bail out of the loop if the program has closed its output
|
|
* descriptors, and we have no more data to send to the
|
|
* client, and there is no pending buffered data.
|
|
*/
|
|
if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
|
|
buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
|
|
if (!channel_still_open())
|
|
break;
|
|
if (!waiting_termination) {
|
|
const char *s = "Waiting for forwarded connections to terminate...\r\n";
|
|
char *cp;
|
|
waiting_termination = 1;
|
|
buffer_append(&stderr_buffer, s, strlen(s));
|
|
|
|
/* Display list of open channels. */
|
|
cp = channel_open_message();
|
|
buffer_append(&stderr_buffer, cp, strlen(cp));
|
|
xfree(cp);
|
|
}
|
|
}
|
|
/* Sleep in select() until we can do something. */
|
|
wait_until_can_do_something(&readset, &writeset,
|
|
max_time_milliseconds);
|
|
|
|
/* Process any channel events. */
|
|
channel_after_select(&readset, &writeset);
|
|
|
|
/* Process input from the client and from program stdout/stderr. */
|
|
process_input(&readset);
|
|
|
|
/* Process output to the client and to program stdin. */
|
|
process_output(&writeset);
|
|
}
|
|
|
|
/* Cleanup and termination code. */
|
|
|
|
/* Wait until all output has been sent to the client. */
|
|
drain_output();
|
|
|
|
debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
|
|
stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);
|
|
|
|
/* Free and clear the buffers. */
|
|
buffer_free(&stdin_buffer);
|
|
buffer_free(&stdout_buffer);
|
|
buffer_free(&stderr_buffer);
|
|
|
|
/* Close the file descriptors. */
|
|
if (fdout != -1)
|
|
close(fdout);
|
|
fdout = -1;
|
|
fdout_eof = 1;
|
|
if (fderr != -1)
|
|
close(fderr);
|
|
fderr = -1;
|
|
fderr_eof = 1;
|
|
if (fdin != -1)
|
|
close(fdin);
|
|
fdin = -1;
|
|
|
|
/* Stop listening for channels; this removes unix domain sockets. */
|
|
channel_stop_listening();
|
|
|
|
/* Wait for the child to exit. Get its exit status. */
|
|
wait_pid = wait(&wait_status);
|
|
if (wait_pid < 0) {
|
|
/*
|
|
* It is possible that the wait was handled by SIGCHLD
|
|
* handler. This may result in either: this call
|
|
* returning with EINTR, or: this call returning ECHILD.
|
|
*/
|
|
if (child_terminated)
|
|
wait_status = child_wait_status;
|
|
else
|
|
packet_disconnect("wait: %.100s", strerror(errno));
|
|
} else {
|
|
/* Check if it matches the process we forked. */
|
|
if (wait_pid != pid)
|
|
error("Strange, wait returned pid %d, expected %d",
|
|
wait_pid, pid);
|
|
}
|
|
|
|
/* We no longer want our SIGCHLD handler to be called. */
|
|
signal(SIGCHLD, SIG_DFL);
|
|
|
|
/* Check if it exited normally. */
|
|
if (WIFEXITED(wait_status)) {
|
|
/* Yes, normal exit. Get exit status and send it to the client. */
|
|
debug("Command exited with status %d.", WEXITSTATUS(wait_status));
|
|
packet_start(SSH_SMSG_EXITSTATUS);
|
|
packet_put_int(WEXITSTATUS(wait_status));
|
|
packet_send();
|
|
packet_write_wait();
|
|
|
|
/*
|
|
* Wait for exit confirmation. Note that there might be
|
|
* other packets coming before it; however, the program has
|
|
* already died so we just ignore them. The client is
|
|
* supposed to respond with the confirmation when it receives
|
|
* the exit status.
|
|
*/
|
|
do {
|
|
int plen;
|
|
type = packet_read(&plen);
|
|
}
|
|
while (type != SSH_CMSG_EXIT_CONFIRMATION);
|
|
|
|
debug("Received exit confirmation.");
|
|
return;
|
|
}
|
|
/* Check if the program terminated due to a signal. */
|
|
if (WIFSIGNALED(wait_status))
|
|
packet_disconnect("Command terminated on signal %d.",
|
|
WTERMSIG(wait_status));
|
|
|
|
/* Some weird exit cause. Just exit. */
|
|
packet_disconnect("wait returned status %04x.", wait_status);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
void
|
|
server_loop2(void)
|
|
{
|
|
fd_set readset, writeset;
|
|
int had_channel = 0;
|
|
int status;
|
|
pid_t pid;
|
|
|
|
debug("Entering interactive session for SSH2.");
|
|
|
|
signal(SIGCHLD, sigchld_handler2);
|
|
child_terminated = 0;
|
|
connection_in = packet_get_connection_in();
|
|
connection_out = packet_get_connection_out();
|
|
max_fd = connection_in;
|
|
if (connection_out > max_fd)
|
|
max_fd = connection_out;
|
|
server_init_dispatch();
|
|
|
|
for (;;) {
|
|
process_buffered_input_packets();
|
|
if (!had_channel && channel_still_open())
|
|
had_channel = 1;
|
|
if (had_channel && !channel_still_open()) {
|
|
debug("!channel_still_open.");
|
|
break;
|
|
}
|
|
if (packet_not_very_much_data_to_write())
|
|
channel_output_poll();
|
|
wait_until_can_do_something(&readset, &writeset, 0);
|
|
if (child_terminated) {
|
|
while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
|
|
session_close_by_pid(pid, status);
|
|
child_terminated = 0;
|
|
}
|
|
channel_after_select(&readset, &writeset);
|
|
process_input(&readset);
|
|
process_output(&writeset);
|
|
}
|
|
signal(SIGCHLD, SIG_DFL);
|
|
while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
|
|
session_close_by_pid(pid, status);
|
|
channel_stop_listening();
|
|
}
|
|
|
|
void
|
|
server_input_stdin_data(int type, int plen)
|
|
{
|
|
char *data;
|
|
unsigned int data_len;
|
|
|
|
/* Stdin data from the client. Append it to the buffer. */
|
|
/* Ignore any data if the client has closed stdin. */
|
|
if (fdin == -1)
|
|
return;
|
|
data = packet_get_string(&data_len);
|
|
packet_integrity_check(plen, (4 + data_len), type);
|
|
buffer_append(&stdin_buffer, data, data_len);
|
|
memset(data, 0, data_len);
|
|
xfree(data);
|
|
}
|
|
|
|
void
|
|
server_input_eof(int type, int plen)
|
|
{
|
|
/*
|
|
* Eof from the client. The stdin descriptor to the
|
|
* program will be closed when all buffered data has
|
|
* drained.
|
|
*/
|
|
debug("EOF received for stdin.");
|
|
packet_integrity_check(plen, 0, type);
|
|
stdin_eof = 1;
|
|
}
|
|
|
|
void
|
|
server_input_window_size(int type, int plen)
|
|
{
|
|
int row = packet_get_int();
|
|
int col = packet_get_int();
|
|
int xpixel = packet_get_int();
|
|
int ypixel = packet_get_int();
|
|
|
|
debug("Window change received.");
|
|
packet_integrity_check(plen, 4 * 4, type);
|
|
if (fdin != -1)
|
|
pty_change_window_size(fdin, row, col, xpixel, ypixel);
|
|
}
|
|
|
|
int
|
|
input_direct_tcpip(void)
|
|
{
|
|
int sock;
|
|
char *target, *originator;
|
|
int target_port, originator_port;
|
|
|
|
target = packet_get_string(NULL);
|
|
target_port = packet_get_int();
|
|
originator = packet_get_string(NULL);
|
|
originator_port = packet_get_int();
|
|
packet_done();
|
|
|
|
debug("open direct-tcpip: from %s port %d to %s port %d",
|
|
originator, originator_port, target, target_port);
|
|
|
|
/* XXX check permission */
|
|
if (no_port_forwarding_flag) {
|
|
xfree(target);
|
|
xfree(originator);
|
|
return -1;
|
|
}
|
|
sock = channel_connect_to(target, target_port);
|
|
xfree(target);
|
|
xfree(originator);
|
|
if (sock < 0)
|
|
return -1;
|
|
return channel_new("direct-tcpip", SSH_CHANNEL_OPEN,
|
|
sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
|
|
CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("direct-tcpip"));
|
|
}
|
|
|
|
void
|
|
server_input_channel_open(int type, int plen)
|
|
{
|
|
Channel *c = NULL;
|
|
char *ctype;
|
|
int id;
|
|
unsigned int len;
|
|
int rchan;
|
|
int rmaxpack;
|
|
int rwindow;
|
|
|
|
ctype = packet_get_string(&len);
|
|
rchan = packet_get_int();
|
|
rwindow = packet_get_int();
|
|
rmaxpack = packet_get_int();
|
|
|
|
debug("channel_input_open: ctype %s rchan %d win %d max %d",
|
|
ctype, rchan, rwindow, rmaxpack);
|
|
|
|
if (strcmp(ctype, "session") == 0) {
|
|
debug("open session");
|
|
packet_done();
|
|
/*
|
|
* A server session has no fd to read or write
|
|
* until a CHANNEL_REQUEST for a shell is made,
|
|
* so we set the type to SSH_CHANNEL_LARVAL.
|
|
* Additionally, a callback for handling all
|
|
* CHANNEL_REQUEST messages is registered.
|
|
*/
|
|
id = channel_new(ctype, SSH_CHANNEL_LARVAL,
|
|
-1, -1, -1, 0, CHAN_SES_PACKET_DEFAULT,
|
|
0, xstrdup("server-session"));
|
|
if (session_open(id) == 1) {
|
|
channel_register_callback(id, SSH2_MSG_CHANNEL_REQUEST,
|
|
session_input_channel_req, (void *)0);
|
|
channel_register_cleanup(id, session_close_by_channel);
|
|
c = channel_lookup(id);
|
|
} else {
|
|
debug("session open failed, free channel %d", id);
|
|
channel_free(id);
|
|
}
|
|
} else if (strcmp(ctype, "direct-tcpip") == 0) {
|
|
id = input_direct_tcpip();
|
|
if (id >= 0)
|
|
c = channel_lookup(id);
|
|
}
|
|
if (c != NULL) {
|
|
debug("confirm %s", ctype);
|
|
c->remote_id = rchan;
|
|
c->remote_window = rwindow;
|
|
c->remote_maxpacket = rmaxpack;
|
|
|
|
packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
|
|
packet_put_int(c->remote_id);
|
|
packet_put_int(c->self);
|
|
packet_put_int(c->local_window);
|
|
packet_put_int(c->local_maxpacket);
|
|
packet_send();
|
|
} else {
|
|
debug("failure %s", ctype);
|
|
packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
|
|
packet_put_int(rchan);
|
|
packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
|
|
packet_put_cstring("bla bla");
|
|
packet_put_cstring("");
|
|
packet_send();
|
|
}
|
|
xfree(ctype);
|
|
}
|
|
|
|
void
|
|
server_init_dispatch_20()
|
|
{
|
|
debug("server_init_dispatch_20");
|
|
dispatch_init(&dispatch_protocol_error);
|
|
dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
|
|
dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
|
|
dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
|
|
dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
|
|
dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open);
|
|
dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
|
|
dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
|
|
dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &channel_input_channel_request);
|
|
dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
|
|
}
|
|
void
|
|
server_init_dispatch_13()
|
|
{
|
|
debug("server_init_dispatch_13");
|
|
dispatch_init(NULL);
|
|
dispatch_set(SSH_CMSG_EOF, &server_input_eof);
|
|
dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
|
|
dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
|
|
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);
|
|
}
|
|
void
|
|
server_init_dispatch_15()
|
|
{
|
|
server_init_dispatch_13();
|
|
debug("server_init_dispatch_15");
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
|
|
dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
|
|
}
|
|
void
|
|
server_init_dispatch()
|
|
{
|
|
if (compat20)
|
|
server_init_dispatch_20();
|
|
else if (compat13)
|
|
server_init_dispatch_13();
|
|
else
|
|
server_init_dispatch_15();
|
|
}
|