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/*
* Dropbear - a SSH2 server
*
* Copyright (c) 2002,2003 Matt Johnston
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE. */
#include "includes.h"
#include "packet.h"
#include "session.h"
#include "dbutil.h"
#include "ssh.h"
#include "algo.h"
#include "buffer.h"
#include "kex.h"
#include "random.h"
#include "service.h"
#include "auth.h"
#include "channel.h"
static void svr_process_postauth_packet(unsigned int type);
/* process a decrypted packet, call the appropriate handler */
void svr_process_packet() {
unsigned char type;
TRACE(("enter process_packet"));
type = buf_getbyte(ses.payload);
TRACE(("process_packet: packet type = %d", type));
/* these packets we can receive at any time, regardless of expecting
* other packets: */
switch(type) {
case SSH_MSG_IGNORE:
case SSH_MSG_DEBUG:
TRACE(("received SSH_MSG_IGNORE or SSH_MSG_DEBUG"));
goto out;
case SSH_MSG_UNIMPLEMENTED:
/* debugging XXX */
TRACE(("SSH_MSG_UNIMPLEMENTED"));
dropbear_exit("received SSH_MSG_UNIMPLEMENTED");
case SSH_MSG_DISCONNECT:
/* TODO cleanup? */
dropbear_close("Disconnect received");
}
/* Check if we should ignore this packet. Used currently only for
* KEX code, with first_kex_packet_follows */
if (ses.ignorenext) {
TRACE(("Ignoring packet, type = %d", type));
ses.ignorenext = 0;
goto out;
}
/* check that we aren't expecting a particular packet */
if (ses.expecting && ses.expecting != type) {
/* TODO send disconnect? */
dropbear_exit("unexpected packet type %d, expected %d", type,
ses.expecting);
}
/* handle the packet depending on type */
ses.expecting = 0;
switch (type) {
case SSH_MSG_SERVICE_REQUEST:
recv_msg_service_request();
break;
case SSH_MSG_USERAUTH_REQUEST:
recv_msg_userauth_request();
break;
case SSH_MSG_KEXINIT:
recv_msg_kexinit();
break;
case SSH_MSG_KEXDH_INIT:
recv_msg_kexdh_init();
break;
case SSH_MSG_NEWKEYS:
recv_msg_newkeys();
break;
/* this is ugly, need to make a cleaner way to do it */
case SSH_MSG_CHANNEL_DATA:
case SSH_MSG_CHANNEL_WINDOW_ADJUST:
case SSH_MSG_CHANNEL_REQUEST:
case SSH_MSG_CHANNEL_OPEN:
case SSH_MSG_CHANNEL_EOF:
case SSH_MSG_CHANNEL_CLOSE:
case SSH_MSG_CHANNEL_OPEN_CONFIRMATION:
case SSH_MSG_CHANNEL_OPEN_FAILURE:
case SSH_MSG_GLOBAL_REQUEST:
/* these should be checked for authdone below */
svr_process_postauth_packet(type);
break;
default:
/* TODO this possibly should be handled */
TRACE(("preauth unknown packet"));
recv_unimplemented();
break;
}
out:
buf_free(ses.payload);
ses.payload = NULL;
TRACE(("leave process_packet"));
}
/* process a packet, and also check that auth has been done */
static void svr_process_postauth_packet(unsigned int type) {
/* messages following here require userauth before use */
/* IF YOU ADD MORE PACKET TYPES, MAKE SURE THEY'RE ALSO ADDED TO THE LIST
* IN process_packet() XXX XXX XXX */
if (!svr_ses.authstate.authdone) {
dropbear_exit("received message %d before userauth", type);
}
switch (type) {
case SSH_MSG_CHANNEL_DATA:
recv_msg_channel_data();
break;
case SSH_MSG_CHANNEL_WINDOW_ADJUST:
recv_msg_channel_window_adjust();
break;
#ifndef DISABLE_REMOTETCPFWD
case SSH_MSG_GLOBAL_REQUEST:
/* currently only used for remote tcp, so we cheat a little */
recv_msg_global_request_remotetcp();
break;
#endif
case SSH_MSG_CHANNEL_REQUEST:
recv_msg_channel_request();
break;
case SSH_MSG_CHANNEL_OPEN:
recv_msg_channel_open();
break;
case SSH_MSG_CHANNEL_EOF:
recv_msg_channel_eof();
break;
case SSH_MSG_CHANNEL_CLOSE:
recv_msg_channel_close();
break;
#ifdef USE_LISTENERS /* for x11, tcp fwd etc */
case SSH_MSG_CHANNEL_OPEN_CONFIRMATION:
recv_msg_channel_open_confirmation();
break;
case SSH_MSG_CHANNEL_OPEN_FAILURE:
recv_msg_channel_open_failure();
break;
#endif
default:
TRACE(("unknown packet()"));
recv_unimplemented();
break;
}
}
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