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/*
* active port forwarder - software for secure forwarding
* Copyright (C) 2003-2007 jeremian <jeremian [at] poczta.fm>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include <config.h>
#include "client_reverse_udp.h"
#include <stdlib.h>
/*
* Function name: initialize_client_reverse_udp
* Description: Initializes the realm for reverse udp connection.
* Arguments: cr - pointer to ClientRealm structure
* Returns: 0 - connection was initialized successfully,
* 1 - connection initialization failed.
*/
int
initialize_client_reverse_udp(ClientRealm* cr)
{
int tmp;
int wanttoexit = (ArOptions_get_arStart(ClientRealm_get_arOptions(cr)) == AR_OPTION_ENABLED) ? 0 : 1;
ClientRealm_set_usersLimit(cr, 1);
if (ip_connect(&tmp, ClientRealm_get_serverName(cr),
ClientRealm_get_managePort(cr),
ClientRealm_get_ipFamily(cr), NULL, NULL)) {
#ifdef AF_INET6
aflog(LOG_T_INIT, LOG_I_CRIT,
"tcp_connect_%s error for %s, %s",
(ClientRealm_get_ipFamily(cr) & 0x02) ?
"ipv4" : (ClientRealm_get_ipFamily(cr) & 0x04) ?
"ipv6":"unspec", ClientRealm_get_serverName(cr), ClientRealm_get_managePort(cr));
#else
aflog(LOG_T_INIT, LOG_I_CRIT,
"tcp_connect error for %s, %s", ClientRealm_get_serverName(cr), ClientRealm_get_managePort(cr));
#endif
if (wanttoexit) {
exit(1);
}
else {
return 1;
}
}
SslFd_set_fd(ClientRealm_get_masterSslFd(cr), tmp);
SslFd_set_ssl(ClientRealm_get_masterSslFd(cr), NULL);
return 0;
}
/*
* Function name: client_reverse_udp
* Description: This function is responsible for the client part of the reverse udp tunnel.
* Arguments: cr - pointer to ClientRealm structure
* buff - buffer which will be used for communication
* buflength - socket send buffer size
*/
void
client_reverse_udp(ClientRealm* cr, unsigned char* buff, int buflength)
{
socklen_t len, addrlen;
int maxfdp1, temp, n, length;
#ifdef HAVE_LINUX_SOCKIOS_H
int notsent;
#endif
struct sockaddr* cliaddr;
fd_set rset, allset;
if (ip_listen(&temp, ClientRealm_get_hostName(cr),
PortListNode_get_portName(PortList_get_nth(ClientRealm_get_destinationPorts(cr), 0)), &addrlen,
ClientRealm_get_ipFamily(cr) & 0xfe)) {
#ifdef AF_INET6
aflog(LOG_T_INIT, LOG_I_DEBUG,
"udp_listen_%s error for %s, %s",
(ClientRealm_get_ipFamily(cr) & 0x02) ?
"ipv4":(ClientRealm_get_ipFamily(cr) & 0x04) ?
"ipv6":"unspec", ClientRealm_get_hostName(cr),
PortListNode_get_portName(PortList_get_nth(ClientRealm_get_destinationPorts(cr), 0)));
#else
aflog(LOG_T_INIT, LOG_I_DEBUG,
"udp_listen error for %s, %s", ClientRealm_get_hostName(cr),
PortListNode_get_portName(PortList_get_nth(ClientRealm_get_destinationPorts(cr), 0)));
#endif
exit(1);
}
ConnectUser_set_connFd(ClientRealm_get_usersTable(cr)[0], temp);
cliaddr = malloc(addrlen);
FD_ZERO(&allset);
FD_SET(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), &allset);
maxfdp1 = SslFd_get_fd(ClientRealm_get_masterSslFd(cr)) + 1;
maxfdp1 = (maxfdp1 > (ConnectUser_get_connFd(ClientRealm_get_usersTable(cr)[0]) + 1)) ?
maxfdp1 : (ConnectUser_get_connFd(ClientRealm_get_usersTable(cr)[0]) + 1);
FD_SET(ConnectUser_get_connFd(ClientRealm_get_usersTable(cr)[0]), &allset);
aflog(LOG_T_CLIENT, LOG_I_INFO,
"CLIENT STARTED mode: udp reverse");
for ( ; ; ) {
len = 4;
if (getsockopt(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), SOL_SOCKET, SO_SNDBUF, &temp, &len) != -1) {
if (temp != buflength) {
buflength = temp;
aflog(LOG_T_CLIENT, LOG_I_WARNING,
"Send buffer size changed...");
}
}
len = addrlen;
rset = allset;
aflog(LOG_T_MAIN, LOG_I_DEBUG,
"select");
select(maxfdp1, &rset, NULL, NULL, NULL);
aflog(LOG_T_MAIN, LOG_I_DEBUG,
"after select...");
if (FD_ISSET(ConnectUser_get_connFd(ClientRealm_get_usersTable(cr)[0]), &rset)) { /* FD_ISSET CONTABLE[0].CONNFD RSET*/
n = recvfrom(ConnectUser_get_connFd(ClientRealm_get_usersTable(cr)[0]), &buff[5], 8091, 0, cliaddr, &len);
#ifdef HAVE_LINUX_SOCKIOS_H
# ifdef SIOCOUTQ
aflog(LOG_T_MAIN, LOG_I_DDEBUG,
"SIOCOUTQ is defined");
if (ioctl(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), SIOCOUTQ, ¬sent)) {
aflog(LOG_T_CLIENT, LOG_I_CRIT,
"ioctl error -> exiting...");
exit(1);
}
if (buflength <= notsent + n + 5) { /* when we can't do this */
aflog(LOG_T_CLIENT, LOG_I_INFO,
"drop: size:%d, buf:%d, w:%d/%d", n, buflength, notsent, buflength);
# else
aflog(LOG_T_MAIN< LOG_I_DDEBUG,
"TIOCOUTQ is defined");
if (ioctl(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), TIOCOUTQ, ¬sent)) {
aflog(LOG_T_CLIENT, LOG_I_CRIT,
"ioctl error -> exiting...");
exit(1);
}
if (notsent <= n + 5) { /* when we can't do this */
aflog(LOG_T_CLIENT, LOG_I_INFO,
"drop: size:%d, buf:%d, w:%d/%d", n, buflength, buflength - notsent, buflength);
# endif
}
else {
#endif
if (n > 0) {
#ifdef HAVE_LINUX_SOCKIOS_H
aflog(LOG_T_CLIENT, LOG_I_INFO,
"Sending %d bytes to service (w:%d/%d) (FROM:%s)", n,
# ifdef SIOCOUTQ
notsent
# else
buflength - notsent
# endif
, buflength, sock_ntop(cliaddr, len, NULL, NULL, 0));
#else
aflog(LOG_T_CLIENT, LOG_I_INFO,
"Sending %d bytes to service (FROM:%s)", n, sock_ntop(cliaddr, len, NULL, NULL, 0));
#endif
buff[0] = AF_S_MESSAGE;
buff[1] = AF_S_LOGIN;
buff[2] = AF_S_MESSAGE;
buff[3] = n >> 8;
buff[4] = n;
writen(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), buff, n + 5);
}
#ifdef HAVE_LINUX_SOCKIOS_H
}
#endif
} /* - FD_ISSET CONTABLE[0].CONNFD RSET */
if (FD_ISSET(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), &rset)) { /* FD_ISSET MASTER.COMMFD RSET */
n = readn(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), buff, 5);
if (n == 5) {
if ((buff[0] != AF_S_MESSAGE) || (buff[1] != AF_S_LOGIN) || (buff[2] != AF_S_MESSAGE)) {
aflog(LOG_T_CLIENT, LOG_I_CRIT,
"Incompatible server type (not udp?) or data corruption -> exiting...");
exit(1);
}
length = buff[3];
length = length << 8;
length += buff[4]; /* this is length of message */
n = readn(SslFd_get_fd(ClientRealm_get_masterSslFd(cr)), buff, length);
}
else {
n = 0;
}
if (n == 0) { /* server quits -> we do the same... */
aflog(LOG_T_CLIENT, LOG_I_CRIT,
"premature quit of the server -> exiting...");
exit(1);
}
aflog(LOG_T_CLIENT, LOG_I_INFO,
"Sending %d bytes to user (TO:%s)", n, sock_ntop(cliaddr, addrlen, NULL, NULL, 0));
sendto(ConnectUser_get_connFd(ClientRealm_get_usersTable(cr)[0]), buff, n, 0, cliaddr, addrlen);
} /* - FD_ISSET MASTER.COMMFD RSET */
}
exit(0); /* we shouldn't get here */
}
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