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/*
* Dropbear SSH
*
* 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 "ssh.h"
#include "tcpfwd.h"
#include "dbutil.h"
#include "session.h"
#include "buffer.h"
#include "packet.h"
#include "listener.h"
#include "runopts.h"
#ifdef DROPBEAR_TCP_ACCEPT
static void cleanup_tcp(struct Listener *listener) {
struct TCPListener *tcpinfo = (struct TCPListener*)(listener->typedata);
m_free(tcpinfo->sendaddr);
m_free(tcpinfo->listenaddr);
m_free(tcpinfo);
}
static void tcp_acceptor(struct Listener *listener, int sock) {
int fd;
struct sockaddr_storage addr;
socklen_t len;
char ipstring[NI_MAXHOST], portstring[NI_MAXSERV];
struct TCPListener *tcpinfo = (struct TCPListener*)(listener->typedata);
len = sizeof(addr);
fd = accept(sock, (struct sockaddr*)&addr, &len);
if (fd < 0) {
return;
}
if (getnameinfo((struct sockaddr*)&addr, len, ipstring, sizeof(ipstring),
portstring, sizeof(portstring),
NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
return;
}
if (send_msg_channel_open_init(fd, tcpinfo->chantype) == DROPBEAR_SUCCESS) {
unsigned char* addr = NULL;
unsigned int port = 0;
if (tcpinfo->tcp_type == direct) {
/* "direct-tcpip" */
/* host to connect, port to connect */
addr = tcpinfo->sendaddr;
port = tcpinfo->sendport;
} else {
dropbear_assert(tcpinfo->tcp_type == forwarded);
/* "forwarded-tcpip" */
/* address that was connected, port that was connected */
addr = tcpinfo->listenaddr;
port = tcpinfo->listenport;
}
buf_putstring(ses.writepayload, addr, strlen(addr));
buf_putint(ses.writepayload, port);
/* originator ip */
buf_putstring(ses.writepayload, ipstring, strlen(ipstring));
/* originator port */
buf_putint(ses.writepayload, atol(portstring));
encrypt_packet();
} else {
/* XXX debug? */
close(fd);
}
}
int listen_tcpfwd(struct TCPListener* tcpinfo) {
char portstring[NI_MAXSERV];
int socks[DROPBEAR_MAX_SOCKS];
struct Listener *listener = NULL;
int nsocks;
char* errstring = NULL;
// listen_spec = NULL indicates localhost
const char* listen_spec = NULL;
TRACE(("enter listen_tcpfwd"))
/* first we try to bind, so don't need to do so much cleanup on failure */
snprintf(portstring, sizeof(portstring), "%d", tcpinfo->listenport);
/* a listenaddr of "" will indicate all interfaces */
if (opts.listen_fwd_all
&& (strcmp(tcpinfo->listenaddr, "localhost") != 0) ) {
listen_spec = tcpinfo->listenaddr;
}
nsocks = dropbear_listen(listen_spec, portstring, socks,
DROPBEAR_MAX_SOCKS, &errstring, &ses.maxfd);
if (nsocks < 0) {
dropbear_log(LOG_INFO, "TCP forward failed: %s", errstring);
m_free(errstring);
TRACE(("leave listen_tcpfwd: dropbear_listen failed"))
return DROPBEAR_FAILURE;
}
m_free(errstring);
/* new_listener will close the socks if it fails */
listener = new_listener(socks, nsocks, CHANNEL_ID_TCPFORWARDED, tcpinfo,
tcp_acceptor, cleanup_tcp);
if (listener == NULL) {
TRACE(("leave listen_tcpfwd: listener failed"))
return DROPBEAR_FAILURE;
}
TRACE(("leave listen_tcpfwd: success"))
return DROPBEAR_SUCCESS;
}
#endif /* DROPBEAR_TCP_ACCEPT */
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