LCX端口转发源码分析
Posted ruingking
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了LCX端口转发源码分析相关的知识，希望对你有一定的参考价值。
lcx.exe算是端口转发工具中普及率特别高的吧。当然，最近也出了好些Web端口转发工具，这个待后续再分析一下。我从网上下载了一个lcx的源码片段，结合源码谈谈自己的认识。
lcx工作原理是使不同端口之间形成一个回路，这样就可以进行端口转发。常用于外网连接内网3389端口。具体使用方法网上一堆。
这个程序主要采用Socket来实现，有几个比较重要的函数：bind2bind、bind2conn、conn2conn及transmitdata。transmitdata函数是核心，这个函数作用是使得不同端口之间的数据形成一个回路。
注意源代码中的setsocket函数，其中设置了SO_REUSEADDR。设置SO_REUSEADDR之后，可以应用的一种场景就是同一个端口可以绑定多个socket。查看相关资料可以得知，其实设置SO_REUSEADDR之后，还有其他几种应用场景。我试了一下，你把setsocket函数注释掉，在运行这个端口转发程序时，本地listen的时候设置的两个端口不一样程序还是可以正常运行的。启用setsocket函数之后，本地listen的时候，可以设置两个端口为同一个值，但是这样设置的时候，我在虚拟机中无法远程连接，一直就是尝试连接也不报错。原因不因，未深入分析。
网上很多的源码其实是有问题的，下面我分享一个稍作修改的源代码，能够在windows xp +vc6.0下编译通过，理论上是可以在windows系列所有32位版本下运行的。对于64位系统，我也修改了一个版本，在windows 7 x64+vs2013编译通过，主要用于64位windows下运行。可执行文件我就不放出来了，自己编译运行差不多就OK了。
Windows XP +VC6.0下编译通过的源码：
/*
************************************************************************************
*
* HTran.cpp - HUC Packet Transmit Tool.
*
* Copyright (C) 2000-2004 HUC All Rights Reserved.
*
* Author : lion
* : lion#cnhonker.net
* : <a href="http://www.cnhonker.com" target="_blank">http://www.cnhonker.com</a>
* :
* Notice : Thx to bkbll (bkbll#cnhonker.net)
* :
* Date : 2003-10-20
* :
* Complie : cl HTran.cpp
* :
* Usage : E:>HTran
* : ======================== HUC Packet Transmit Tool V1.00 =======================
* : =========== Code by lion & bkbll, Welcome to <a href="http://www.cnhonker.com" target="_blank">http://www.cnhonker.com</a> ==========
* :
* : [Usage of Packet Transmit:]
* : HTran - [-log logfile]
* :
* : [option:]
* : -listen
* : -tran
* : -slave
*
************************************************************************************
*/
#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>
#include <signal.h>
#include <errno.h>
#include <io.h>
#pragma comment(lib, "ws2_32.lib")
#define VERSION "1.00"
#define TIMEOUT 300
#define MAXSIZE 20480
#define HOSTLEN 40
#define CONNECTNUM 5
// define 2 socket struct
struct transocket
{
SOCKET fd1;
SOCKET fd2;
};
// define function
void ver();
void usage(char *prog);
void transmitdata(LPVOID data);
void getctrlc(int j);
void closeallfd();
void makelog(char *buffer, int length);
void proxy(int port);
void bind2bind(int port1, int port2);
void bind2conn(int port1, char *host, int port2);
void conn2conn(char *host1, int port1, char *host2, int port2);
int testifisvalue(char *str);
int create_socket();
int create_server(int sockfd, int port);
int client_connect(int sockfd, char* server, int port);
// define GLOBAL variable here
extern int errno;
FILE *fp;
int method=0;
//int connectnum=0;
//************************************************************************************
//
// function main 主要是处理用户参数输入的问题
//
//************************************************************************************
VOID main(int argc, char* argv[])
{
char **p;
char sConnectHost[HOSTLEN], sTransmitHost[HOSTLEN];
int iConnectPort=0, iTransmitPort=0;
char *logfile=NULL;
ver();
memset(sConnectHost, 0, HOSTLEN);
memset(sTransmitHost, 0, HOSTLEN);
p=argv;
while(*p)
{
if(stricmp(*p, "-log") == 0)
{
if(testifisvalue(*(p+1)))
{
logfile = *(++p);
}
else
{
printf("[-] ERROR: Must supply logfile name.
");
return;
}
p++;
continue;
}
p++;
}
if(logfile !=NULL)
{
fp=fopen(logfile,"a");
if(fp == NULL )
{
printf("[-] ERROR: open logfile");
return;
}
makelog("====== Start ======
", 22);
}
// Win Start Winsock.
WSADATA wsadata;
WSAStartup(MAKEWORD(2, 2), &wsadata);
signal(SIGINT, &getctrlc);
if(argc > 2)
{
if(stricmp(argv[1], "-listen") == 0 && argc >= 4)
{
iConnectPort = atoi(argv[2]);
iTransmitPort = atoi(argv[3]);
method = 1;
}
else
if(stricmp(argv[1], "-tran") == 0 && argc >= 5)
{
iConnectPort = atoi(argv[2]);
strncpy(sTransmitHost, argv[3], HOSTLEN);
iTransmitPort = atoi(argv[4]);
method = 2;
}
else
if(stricmp(argv[1], "-slave") == 0 && argc >= 6)
{
strncpy(sConnectHost, argv[2], HOSTLEN);
iConnectPort = atoi(argv[3]);
strncpy(sTransmitHost, argv[4], HOSTLEN);
iTransmitPort = atoi(argv[5]);
method = 3;
}
}
switch(method)
{
case 1:
bind2bind(iConnectPort, iTransmitPort);
break;
case 2:
bind2conn(iConnectPort, sTransmitHost, iTransmitPort);
break;
case 3:
conn2conn(sConnectHost, iConnectPort, sTransmitHost, iTransmitPort);
break;
default:
usage(argv[0]);
break;
}
if(method)
{
closeallfd();
}
WSACleanup();
return;
}
//************************************************************************************
//
// print version message
//
//************************************************************************************
VOID ver()
{
printf("======================== HUC Packet Transmit Tool V%s =======================
", VERSION);
printf("=========== Code by lion & bkbll, Welcome to http://www.cnhonker.com==========
");
}
//************************************************************************************
//
// print usage message
//
//************************************************************************************
VOID usage(char* prog)
{
printf("[Usage of Packet Transmit:]
");
printf(" %s - [-log logfile]
", prog);
printf("[option:]
");
printf(" -listen
");
printf(" -tran
");
printf(" -slave
");
return;
}
//************************************************************************************
//
// test if is value
//
//************************************************************************************
int testifisvalue(char *str)
{
if(str == NULL ) return(0);
if(str[0]==‘-‘) return(0);
return(1);
}
//************************************************************************************
//
// LocalHost:ConnectPort transmit to LocalHost:TransmitPort
//
//************************************************************************************
void bind2bind(int port1, int port2)
{
SOCKET fd1,fd2, sockfd1, sockfd2;
struct sockaddr_in client1,client2;
int size1,size2;
HANDLE hThread=NULL;
transocket sock;
DWORD dwThreadID;
if((fd1=create_socket())==0) return;
if((fd2=create_socket())==0) return;
printf("[+] Listening port %d ......
",port1);
fflush(stdout);
if(create_server(fd1, port1)==0)
{
closesocket(fd1);
return;
}
printf("[+] Listen OK!
");
printf("[+] Listening port %d ......
",port2);
fflush(stdout);
if(create_server(fd2, port2)==0)
{
closesocket(fd2);
return;
}
printf("[+] Listen OK!
");
size1=size2=sizeof(struct sockaddr);
while(1)
{
printf("[+] Waiting for Client on port:%d ......
",port1);
if((sockfd1 = accept(fd1,(struct sockaddr *)&client1,&size1))<0)
{
printf("[-] Accept1 error.
");
continue;
}
printf("[+] Accept a Client on port %d from %s ......
", port1, inet_ntoa(client1.sin_addr));
printf("[+] Waiting another Client on port:%d....
", port2);
if((sockfd2 = accept(fd2, (struct sockaddr *)&client2, &size2))<0)
{
printf("[-] Accept2 error.
");
closesocket(sockfd1);
continue;
}
printf("[+] Accept a Client on port %d from %s
",port2, inet_ntoa(client2.sin_addr));
printf("[+] Accept Connect OK!
");
sock.fd1 = sockfd1;
sock.fd2 = sockfd2;
hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)transmitdata, (LPVOID)&sock, 0, &dwThreadID);
if(hThread == NULL)
{
TerminateThread(hThread, 0);
return;
}
Sleep(1000);
printf("[+] CreateThread OK!
");
}
}
//************************************************************************************
//
// LocalHost:ConnectPort transmit to TransmitHost:TransmitPort
//
//************************************************************************************
void bind2conn(int port1, char *host, int port2)
{
SOCKET sockfd,sockfd1,sockfd2;
struct sockaddr_in remote;
int size;
char buffer[1024];
HANDLE hThread=NULL;
transocket sock;
DWORD dwThreadID;
if (port1 > 65535 || port1 < 1)
{
printf("[-] ConnectPort invalid.
");
return;
}
if (port2 > 65535 || port2 < 1)
{
printf("[-] TransmitPort invalid.
");
return;
}
memset(buffer,0,1024);
if((sockfd=create_socket()) == INVALID_SOCKET) return;
if(create_server(sockfd, port1) == 0)
{
closesocket(sockfd);
return;
}
size=sizeof(struct sockaddr);
while(1)
{
printf("[+] Waiting for Client ......
");
if((sockfd1=accept(sockfd,(struct sockaddr *)&remote,&size))<0)
{
printf("[-] Accept error.
");
continue;
}
printf("[+] Accept a Client from %s:%d ......
",
inet_ntoa(remote.sin_addr), ntohs(remote.sin_port));
if((sockfd2=create_socket())==0)
{
closesocket(sockfd1);
continue;
}
printf("[+] Make a Connection to %s:%d ......
",host,port2);
fflush(stdout);
if(client_connect(sockfd2,host,port2)==0)
{
closesocket(sockfd2);
sprintf(buffer,"[SERVER]connection to %s:%d error
", host, port2);
send(sockfd1,buffer,strlen(buffer),0);
memset(buffer, 0, 1024);
closesocket(sockfd1);
continue;
}
printf("[+] Connect OK!
");
sock.fd1 = sockfd1;
sock.fd2 = sockfd2;
hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)transmitdata, (LPVOID)&sock, 0, &dwThreadID);
if(hThread == NULL)
{
TerminateThread(hThread, 0);
return;
}
Sleep(1000);
printf("[+] CreateThread OK!
");
}
}
//************************************************************************************
//
// ConnectHost:ConnectPort transmit to TransmitHost:TransmitPort
//
//************************************************************************************
void conn2conn(char *host1,int port1,char *host2,int port2)
{
SOCKET sockfd1,sockfd2;
HANDLE hThread=NULL;
transocket sock;
DWORD dwThreadID;
fd_set fds;
int l;
char buffer[MAXSIZE];
while(1)
{
if((sockfd1=create_socket())==0) return;
if((sockfd2=create_socket())==0) return;
printf("[+] Make a Connection to %s:%d....
",host1,port1);
fflush(stdout);
if(client_connect(sockfd1,host1,port1)==0)
{
closesocket(sockfd1);
closesocket(sockfd2);
continue;
}
// fix by bkbll
// if host1:port1 recved data, than connect to host2,port2
l=0;
memset(buffer,0,MAXSIZE);
while(1)
{
FD_ZERO(&fds);
FD_SET(sockfd1, &fds);
if (select(sockfd1+1, &fds, NULL, NULL, NULL) == SOCKET_ERROR)
{
if (errno == WSAEINTR) continue;
break;
}
if (FD_ISSET(sockfd1, &fds))
{
l=recv(sockfd1, buffer, MAXSIZE, 0);
break;
}
Sleep(5);
}
if(l<=0)
{
printf("[-] There is a error...Create a new connection.
");
continue;
}
while(1)
{
printf("[+] Connect OK!
");
printf("[+] Make a Connection to %s:%d....
", host2,port2);
fflush(stdout);
if(client_connect(sockfd2,host2,port2)==0)
{
closesocket(sockfd1);
closesocket(sockfd2);
continue;
}
if(send(sockfd2,buffer,l,0)==SOCKET_ERROR)
{
printf("[-] Send failed.
");
continue;
}
l=0;
memset(buffer,0,MAXSIZE);
break;
}
printf("[+] All Connect OK!
");
sock.fd1 = sockfd1;
sock.fd2 = sockfd2;
hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)transmitdata, (LPVOID)&sock, 0, &dwThreadID);
if(hThread == NULL)
{
TerminateThread(hThread, 0);
return;
}
// connectnum++;
Sleep(1000);
printf("[+] CreateThread OK!
");
}
}
//************************************************************************************
//
// Socket Transmit to Socket
//
//************************************************************************************
void transmitdata(LPVOID data)
{
SOCKET fd1, fd2;
transocket *sock;
struct timeval timeset;
fd_set readfd,writefd;
int result,i=0;
char read_in1[MAXSIZE],send_out1[MAXSIZE];
char read_in2[MAXSIZE],send_out2[MAXSIZE];
int read1=0,totalread1=0,send1=0;
int read2=0,totalread2=0,send2=0;
int sendcount1,sendcount2;
int maxfd;
struct sockaddr_in client1,client2;
int structsize1,structsize2;
char host1[20],host2[20];
int port1=0,port2=0;
char tmpbuf[100];
sock = (transocket *)data;
fd1 = sock->fd1;
fd2 = sock->fd2;
memset(host1,0,20);
memset(host2,0,20);
memset(tmpbuf,0,100);
structsize1=sizeof(struct sockaddr);
structsize2=sizeof(struct sockaddr);
if(getpeername(fd1,(struct sockaddr *)&client1,&structsize1)<0)
{
strcpy(host1, "fd1");
}
else
{
// printf("[+]got, ip:%s, port:%d
",inet_ntoa(client1.sin_addr),ntohs(client1.sin_port));
strcpy(host1, inet_ntoa(client1.sin_addr));
port1=ntohs(client1.sin_port);
}
if(getpeername(fd2,(struct sockaddr *)&client2,&structsize2)<0)
{
strcpy(host2,"fd2");
}
else
{
// printf("[+]got, ip:%s, port:%d
",inet_ntoa(client2.sin_addr),ntohs(client2.sin_port));
strcpy(host2, inet_ntoa(client2.sin_addr));
port2=ntohs(client2.sin_port);
}
printf("[+] Start Transmit (%s:%d <-> %s:%d) ......
", host1, port1, host2, port2);
maxfd=max(fd1,fd2)+1;
memset(read_in1,0,MAXSIZE);
memset(read_in2,0,MAXSIZE);
memset(send_out1,0,MAXSIZE);
memset(send_out2,0,MAXSIZE);
timeset.tv_sec=TIMEOUT;
timeset.tv_usec=0;
while(1)
{
FD_ZERO(&readfd);
FD_ZERO(&writefd);
FD_SET((UINT)fd1, &readfd);
FD_SET((UINT)fd1, &writefd);
FD_SET((UINT)fd2, &writefd);
FD_SET((UINT)fd2, &readfd);
result=select(maxfd,&readfd,&writefd,NULL,×et);
if((result<0) && (errno!=EINTR))
{
printf("[-] Select error.
");
break;
}
else if(result==0)
{
printf("[-] Socket time out.
");
break;
}
if(FD_ISSET(fd1, &readfd))
{
/* must < MAXSIZE-totalread1, otherwise send_out1 will flow */
if(totalread1 < MAXSIZE
) {
read1=recv(fd1, read_in1, MAXSIZE-totalread1, 0);
if((read1==SOCKET_ERROR) || (read1==0))
{
printf("[-] Read fd1 data error,maybe close?
");
break;
}
memcpy(send_out1+totalread1,read_in1,read1);
sprintf(tmpbuf,"
Recv %5d bytes from %s:%d
", read1, host1, port1);
printf(" Recv %5d bytes %16s:%d
", read1, host1, port1);
makelog(tmpbuf,strlen(tmpbuf));
makelog(read_in1,read1);
totalread1+=read1;
memset(read_in1,0,MAXSIZE);
}
}
if(FD_ISSET(fd2, &writefd))
{
int err=0;
sendcount1=0;
while(totalread1>0)
{
send1=send(fd2, send_out1+sendcount1, totalread1, 0);
if(send1==0)break;
if((send1<0) && (errno!=EINTR))
{
printf("[-] Send to fd2 unknow error.
");
err=1;
break;
}
if((send1<0) && (errno==ENOSPC)) break;
sendcount1+=send1;
totalread1-=send1;
printf(" Send %5d bytes %16s:%d
", send1, host2, port2);
}
if(err==1) break;
if((totalread1>0) && (sendcount1>0))
{
/* move not sended data to start addr */
memcpy(send_out1,send_out1+sendcount1,totalread1);
memset(send_out1+totalread1,0,MAXSIZE-totalread1);
}
else
memset(send_out1,0,MAXSIZE);
}
if(FD_ISSET(fd2, &readfd))
{
if(totalread2 < MAXSIZE
) {
read2=recv(fd2,read_in2,MAXSIZE-totalread2, 0);
if(read2==0)break;
if((read2<0) && (errno!=EINTR))
{
printf("[-] Read fd2 data error,maybe close?
");
break;
}
memcpy(send_out2+totalread2,read_in2,read2);
sprintf(tmpbuf, "
Recv %5d bytes from %s:%d
", read2, host2, port2);
printf(" Recv %5d bytes %16s:%d
", read2, host2, port2);
makelog(tmpbuf,strlen(tmpbuf));
makelog(read_in2,read2);
totalread2+=read2;
memset(read_in2,0,MAXSIZE);
}
}
if(FD_ISSET(fd1, &writefd))
{
int err2=0;
sendcount2=0;
while(totalread2>0)
{
send2=send(fd1, send_out2+sendcount2, totalread2, 0);
if(send2==0)break;
if((send2<0) && (errno!=EINTR))
{
printf("[-] Send to fd1 unknow error.
");
err2=1;
break;
}
if((send2<0) && (errno==ENOSPC)) break;
sendcount2+=send2;
totalread2-=send2;
printf(" Send %5d bytes %16s:%d
", send2, host1, port1);
}
if(err2==1) break;
if((totalread2>0) && (sendcount2 > 0))
{
/* move not sended data to start addr */
memcpy(send_out2, send_out2+sendcount2, totalread2);
memset(send_out2+totalread2, 0, MAXSIZE-totalread2);
}
else
memset(send_out2,0,MAXSIZE);
}
Sleep(5);
}
closesocket(fd1);
closesocket(fd2);
// if(method == 3)
// connectnum --;
printf("
[+] OK! I Closed The Two Socket.
");
}
void getctrlc(int j)
{
printf("
[-] Received Ctrl+C
");
closeallfd();
exit(0);
}
void closeallfd()
{
int i;
printf("[+] Let me exit ......
");
fflush(stdout);
for(i=3; i<256; i++)
{
closesocket(i);
}
if(fp != NULL)
{
fprintf(fp,"
====== Exit ======
");
fclose(fp);
}
printf("[+] All Right!
");
}
int create_socket()
{
int sockfd;
sockfd=socket(AF_INET,SOCK_STREAM,0);
if(sockfd<0)
{
printf("[-] Create socket error.
");
return(0);
}
return(sockfd);
}
int create_server(int sockfd,int port)
{
struct sockaddr_in srvaddr;
int on=1;
memset(&srvaddr, 0, sizeof(struct sockaddr));
srvaddr.sin_port=htons(port);
srvaddr.sin_family=AF_INET;
srvaddr.sin_addr.s_addr=htonl(INADDR_ANY);
setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR, (char*)&on,sizeof(on)); //so I can rebind the port
if(bind(sockfd,(struct sockaddr *)&srvaddr,sizeof(struct sockaddr))<0)
{
printf("[-] Socket bind error.
");
return(0);
}
if(listen(sockfd,CONNECTNUM)<0)
{
printf("[-] Socket Listen error.
");
return(0);
}
return(1);
}
int client_connect(int sockfd,char* server,int port)
{
struct sockaddr_in cliaddr;
struct hostent *host;
if(!(host=gethostbyname(server)))
{
printf("[-] Gethostbyname(%s) error:%s
",server,strerror(errno));
return(0);
}
memset(&cliaddr, 0, sizeof(struct sockaddr));
cliaddr.sin_family=AF_INET;
cliaddr.sin_port=htons(port);
cliaddr.sin_addr=*((struct in_addr *)host->h_addr);
if(connect(sockfd,(struct sockaddr *)&cliaddr,sizeof(struct sockaddr))<0)
{
printf("[-] Connect error.
");
return(0);
}
return(1);
}
void makelog(char *buffer,int length)
{
if(fp !=NULL)
{
// fprintf(fp, "%s", buffer);
// printf("%s",buffer);
write(fileno(fp),buffer,length);
// fflush(fp);
}
}
附上效果图一张：
Windows7 64+VS2013编译通过的源码：
/*
************************************************************************************
*
* PortTrans.cpp - Port Forwarding.
*
* Copyright (C) 2015 HUC All Rights Reserved.
*
* Author : pandas
* :
* :
* Date : 2015-4-9
* :
* Complie : cl PortTrans.cpp
* :
* Usage : D:>PortTrans
* : ======================== Port Forwarding Tool V1.00 =======================
* : ========================== Improved by pandas ===========================
* :
* : [Usage of Port Forwarding:]
* : PortTrans - [-log logfile]
* :
* : [option:]
* : -listen
* : -tran
* : -slave
*
************************************************************************************
*/
#define _WINSOCK_DEPRECATED_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>
#include <signal.h>
#include <errno.h>
#include <io.h>
#pragma comment(lib, "ws2_32.lib")
#define VERSION "1.00"
#define TIMEOUT 300
#define MAXSIZE 20480
#define HOSTLEN 40
#define CONNECTNUM 5
// define 2 socket struct
struct transocket
{
SOCKET fd1;
SOCKET fd2;
};
// define function
void ver();
void usage(char *prog);
void transmitdata(LPVOID data);
void getctrlc(int j);
void closeallfd();
void makelog(char *buffer, int length);
void proxy(int port);
void bind2bind(int port1, int port2);
void bind2conn(int port1, char *host, int port2);
void conn2conn(char *host1, int port1, char *host2, int port2);
int testifisvalue(char *str);
int create_socket();
int create_server(int sockfd, int port);
int client_connect(int sockfd, char* server, int port);
// define GLOBAL variable here
//int error;
FILE *fp;
int method = 0;
//int connectnum=0;
//************************************************************************************
//
// function main 主要是处理用户参数输入的问题
//
//************************************************************************************
VOID main(int argc, char* argv[])
{
char **p;
char sConnectHost[HOSTLEN], sTransmitHost[HOSTLEN];
int iConnectPort = 0, iTransmitPort = 0;
char *logfile = NULL;
errno_t err;
ver();
memset(sConnectHost, 0, HOSTLEN);
memset(sTransmitHost, 0, HOSTLEN);
p = argv;
while (*p)
{
if (_stricmp(*p, "-log") == 0)
{
if (testifisvalue(*(p + 1)))
{
logfile = *(++p);
}
else
{
printf("[-] ERROR: Must supply logfile name.
");
return;
}
//p++;
continue;
}
p++;
}
if (logfile != NULL)
{
//fp = fopen(logfile, "a");
err = fopen_s(&fp, logfile, "a");
if (fp == NULL)
{
printf("[-] ERROR: open logfile");
return;
}
makelog("====== Start ======
", 22);
}
// Win Start Winsock.
WSADATA wsadata;
WSAStartup(MAKEWORD(2, 2), &wsadata);
signal(SIGINT, &getctrlc);
if (argc > 2)
{
if (_stricmp(argv[1], "-listen") == 0 && argc >= 4)
{
iConnectPort = atoi(argv[2]);
iTransmitPort = atoi(argv[3]);
method = 1;
}
else
if (_stricmp(argv[1], "-tran") == 0 && argc >= 5)
{
iConnectPort = atoi(argv[2]);
strncpy_s(sTransmitHost, argv[3], HOSTLEN);
iTransmitPort = atoi(argv[4]);
method = 2;
}
else
if (_stricmp(argv[1], "-slave") == 0 && argc >= 6)
{
strncpy_s(sConnectHost, argv[2], HOSTLEN);
iConnectPort = atoi(argv[3]);
strncpy_s(sTransmitHost, argv[4], HOSTLEN);
iTransmitPort = atoi(argv[5]);
method = 3;
}
}
switch (method)
{
case 1:
bind2bind(iConnectPort, iTransmitPort);
break;
case 2:
bind2conn(iConnectPort, sTransmitHost, iTransmitPort);
break;
case 3:
conn2conn(sConnectHost, iConnectPort, sTransmitHost, iTransmitPort);
break;
default:
usage(argv[0]);
break;
}
if (method)
{
closeallfd();
}
WSACleanup();
return;
}
//************************************************************************************
//
// print version message
//
//************************************************************************************
VOID ver()
{
printf("======================== Port Forwarding Tool V%s =======================
", VERSION);
printf("========================== Improved by pandas ===========================
");
}
//************************************************************************************
//
// print usage message
//
//************************************************************************************
VOID usage(char* prog)
{
printf("[Usage of Packet Transmit:]
");
printf(" %s - [-log logfile]
", prog);
printf("[option:]
");
printf(" -listen
");
printf(" -tran
");
printf(" -slave
");
return;
}
//************************************************************************************
//
// test if is value
//
//************************************************************************************
int testifisvalue(char *str)
{
if (str == NULL) return(0);
if (str[0] == ‘-‘) return(0);
return(1);
}
//************************************************************************************
//
// LocalHost:ConnectPort transmit to LocalHost:TransmitPort
//
//************************************************************************************
void bind2bind(int port1, int port2)
{
SOCKET fd1, fd2, sockfd1, sockfd2;
struct sockaddr_in client1, client2;
int size1, size2;
HANDLE hThread = NULL;
transocket sock;
DWORD dwThreadID;
if ((fd1 = create_socket()) == 0) return;
if ((fd2 = create_socket()) == 0) return;
printf("[+] Listening port %d ......
", port1);
fflush(stdout);
if (create_server(fd1, port1) == 0)
{
closesocket(fd1);
return;
}
printf("[+] Listen OK!
");
printf("[+] Listening port %d ......
", port2);
fflush(stdout);
if (create_server(fd2, port2) == 0)
{
closesocket(fd2);
return;
}
printf("[+] Listen OK!
");
size1 = size2 = sizeof(struct sockaddr);
while (1)
{
printf("[+] Waiting for Client on port:%d ......
", port1);
if ((sockfd1 = accept(fd1, (struct sockaddr *)&client1, &size1))<0)
{
printf("[-] Accept1 error.
");
continue;
}
printf("[+] Accept a Client on port %d from %s ......
", port1, inet_ntoa(client1.sin_addr));
printf("[+] Waiting another Client on port:%d....
", port2);
if ((sockfd2 = accept(fd2, (struct sockaddr *)&client2, &size2))<0)
{
printf("[-] Accept2 error.
");
closesocket(sockfd1);
continue;
}
printf("[+] Accept a Client on port %d from %s
", port2, inet_ntoa(client2.sin_addr));
printf("[+] Accept Connect OK!
");
sock.fd1 = sockfd1;
sock.fd2 = sockfd2;
hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)transmitdata, (LPVOID)&sock, 0, &dwThreadID);
if (hThread == NULL)
{
TerminateThread(hThread, 0);
return;
}
Sleep(1000);
printf("[+] CreateThread OK!
");
}
}
//************************************************************************************
//
// LocalHost:ConnectPort transmit to TransmitHost:TransmitPort
//
//************************************************************************************
void bind2conn(int port1, char *host, int port2)
{
SOCKET sockfd, sockfd1, sockfd2;
struct sockaddr_in remote;
int size;
char buffer[1024];
HANDLE hThread = NULL;
transocket sock;
DWORD dwThreadID;
if (port1 > 65535 || port1 < 1)
{
printf("[-] ConnectPort invalid.
");
return;
}
if (port2 > 65535 || port2 < 1)
{
printf("[-] TransmitPort invalid.
");
return;
}
memset(buffer, 0, 1024);
if ((sockfd = create_socket()) == INVALID_SOCKET) return;
if (create_server(sockfd, port1) == 0)
{
closesocket(sockfd);
return;
}
size = sizeof(struct sockaddr);
while (1)
{
printf("[+] Waiting for Client ......
");
if ((sockfd1 = accept(sockfd, (struct sockaddr *)&remote, &size))<0)
{
printf("[-] Accept error.
");
continue;
}
printf("[+] Accept a Client from %s:%d ......
",
inet_ntoa(remote.sin_addr), ntohs(remote.sin_port));
if ((sockfd2 = create_socket()) == 0)
{
closesocket(sockfd1);
continue;
}
printf("[+] Make a Connection to %s:%d ......
", host, port2);
fflush(stdout);
if (client_connect(sockfd2, host, port2) == 0)
{
closesocket(sockfd2);
sprintf_s(buffer, "[SERVER]connection to %s:%d error
", host, port2);
send(sockfd1, buffer, strlen(buffer), 0);
memset(buffer, 0, 1024);
closesocket(sockfd1);
continue;
}
printf("[+] Connect OK!
");
sock.fd1 = sockfd1;
sock.fd2 = sockfd2;
hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)transmitdata, (LPVOID)&sock, 0, &dwThreadID);
if (hThread == NULL)
{
TerminateThread(hThread, 0);
return;
}
Sleep(1000);
printf("[+] CreateThread OK!
");
}
}
//************************************************************************************
//
// ConnectHost:ConnectPort transmit to TransmitHost:TransmitPort
//
//************************************************************************************
void conn2conn(char *host1, int port1, char *host2, int port2)
{
SOCKET sockfd1, sockfd2;
HANDLE hThread = NULL;
transocket sock;
DWORD dwThreadID;
fd_set fds;
int l;
char buffer[MAXSIZE];
while (1)
{
/*
while(connectnum)
{
if(connectnum < CONNECTNUM)
{
Sleep(10000);
break;
}
else
{
Sleep(TIMEOUT*1000);
continue;
}
}
*/
if ((sockfd1 = create_socket()) == 0) return;
if ((sockfd2 = create_socket()) == 0) return;
printf("[+] Make a Connection to %s:%d....
", host1, port1);
fflush(stdout);
if (client_connect(sockfd1, host1, port1) == 0)
{
closesocket(sockfd1);
closesocket(sockfd2);
continue;
}
// fix by bkbll
// if host1:port1 recved data, than connect to host2,port2
l = 0;
memset(buffer, 0, MAXSIZE);
while (1)
{
FD_ZERO(&fds);
FD_SET(sockfd1, &fds);
if (select(sockfd1 + 1, &fds, NULL, NULL, NULL) == SOCKET_ERROR)
{
if (errno== WSAEINTR) continue;
break;
}
if (FD_ISSET(sockfd1, &fds))
{
l = recv(sockfd1, buffer, MAXSIZE, 0);
break;
}
Sleep(5);
}
if (l <= 0)
{
printf("[-] There is a error...Create a new connection.
");
continue;
}
while (1)
{
printf("[+] Connect OK!
");
printf("[+] Make a Connection to %s:%d....
", host2, port2);
fflush(stdout);
if (client_connect(sockfd2, host2, port2) == 0)
{
closesocket(sockfd1);
closesocket(sockfd2);
continue;
}
if (send(sockfd2, buffer, l, 0) == SOCKET_ERROR)
{
printf("[-] Send failed.
");
continue;
}
l = 0;
memset(buffer, 0, MAXSIZE);
break;
}
printf("[+] All Connect OK!
");
sock.fd1 = sockfd1;
sock.fd2 = sockfd2;
hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)transmitdata, (LPVOID)&sock, 0, &dwThreadID);
if (hThread == NULL)
{
TerminateThread(hThread, 0);
return;
}
// connectnum++;
Sleep(1000);
printf("[+] CreateThread OK!
");
}
}
//************************************************************************************
//
// Socket Transmit to Socket
//
//************************************************************************************
void transmitdata(LPVOID data)
{
SOCKET fd1, fd2;
transocket *sock;
struct timeval timeset;
fd_set readfd, writefd;
int result, i = 0;
char read_in1[MAXSIZE], send_out1[MAXSIZE];
char read_in2[MAXSIZE], send_out2[MAXSIZE];
int read1 = 0, totalread1 = 0, send1 = 0;
int read2 = 0, totalread2 = 0, send2 = 0;
int sendcount1, sendcount2;
int maxfd;
struct sockaddr_in client1, client2;
int structsize1, structsize2;
char host1[20], host2[20];
int port1 = 0, port2 = 0;
char tmpbuf[100];
sock = (transocket *)data;
fd1 = sock->fd1;
fd2 = sock->fd2;
memset(host1, 0, 20);
memset(host2, 0, 20);
memset(tmpbuf, 0, 100);
structsize1 = sizeof(struct sockaddr);
structsize2 = sizeof(struct sockaddr);
if (getpeername(fd1, (struct sockaddr *)&client1, &structsize1)<0)
{
strcpy_s(host1, "fd1");
}
else
{
// printf("[+]got, ip:%s, port:%d
",inet_ntoa(client1.sin_addr),ntohs(client1.sin_port));
strcpy_s(host1, inet_ntoa(client1.sin_addr));
port1 = ntohs(client1.sin_port);
}
if (getpeername(fd2, (struct sockaddr *)&client2, &structsize2)<0)
{
strcpy_s(host2, "fd2");
}
else
{
// printf("[+]got, ip:%s, port:%d
",inet_ntoa(client2.sin_addr),ntohs(client2.sin_port));
strcpy_s(host2, inet_ntoa(client2.sin_addr));
port2 = ntohs(client2.sin_port);
}
printf("[+] Start Transmit (%s:%d <-> %s:%d) ......
", host1, port1, host2, port2);
maxfd = max(fd1, fd2) + 1;
memset(read_in1, 0, MAXSIZE);
memset(read_in2, 0, MAXSIZE);
memset(send_out1, 0, MAXSIZE);
memset(send_out2, 0, MAXSIZE);
timeset.tv_sec = TIMEOUT;
timeset.tv_usec = 0;
while (1)
{
FD_ZERO(&readfd);
FD_ZERO(&writefd);
FD_SET((UINT)fd1, &readfd);
FD_SET((UINT)fd1, &writefd);
FD_SET((UINT)fd2, &writefd);
FD_SET((UINT)fd2, &readfd);
result = select(maxfd, &readfd, &writefd, NULL, ×et);
if ((result<0) && (errno!= EINTR))
{
printf("[-] Select error.
");
break;
}
else if (result == 0)
{
printf("[-] Socket time out.
");
break;
}
if (FD_ISSET(fd1, &readfd))
{
/* must < MAXSIZE-totalread1, otherwise send_out1 will flow */
if (totalread1 < MAXSIZE) {
read1 = recv(fd1, read_in1, MAXSIZE - totalread1, 0);
if ((read1 == SOCKET_ERROR) || (read1 == 0))
{
printf("[-] Read fd1 data error,maybe close?
");
break;
}
memcpy(send_out1 + totalread1, read_in1, read1);
sprintf_s(tmpbuf, "
Recv %5d bytes from %s:%d
", read1, host1, port1);
printf(" Recv %5d bytes %16s:%d
", read1, host1, port1);
makelog(tmpbuf, strlen(tmpbuf));
makelog(read_in1, read1);
totalread1 += read1;
memset(read_in1, 0, MAXSIZE);
}
}
if (FD_ISSET(fd2, &writefd))
{
int err = 0;
sendcount1 = 0;
while (totalread1>0)
{
send1 = send(fd2, send_out1 + sendcount1, totalread1, 0);
if (send1 == 0)break;
if ((send1<0) && (errno != EINTR))
{
printf("[-] Send to fd2 unknow error.
");
err = 1;
break;
}
if ((send1<0) && (errno == ENOSPC)) break;
sendcount1 += send1;
totalread1 -= send1;
printf(" Send %5d bytes %16s:%d
", send1, host2, port2);
}
if (err == 1) break;
if ((totalread1>0) && (sendcount1>0))
{
/* move not sended data to start addr */
memcpy(send_out1, send_out1 + sendcount1, totalread1);
memset(send_out1 + totalread1, 0, MAXSIZE - totalread1);
}
else
memset(send_out1, 0, MAXSIZE);
}
if (FD_ISSET(fd2, &readfd))
{
if (totalread2 < MAXSIZE) {
read2 = recv(fd2, read_in2, MAXSIZE - totalread2, 0);
if (read2 == 0)break;
if ((read2<0) && (errno != EINTR))
{
printf("[-] Read fd2 data error,maybe close?
");
break;
}
memcpy(send_out2 + totalread2, read_in2, read2);
sprintf_s(tmpbuf, "
Recv %5d bytes from %s:%d
", read2, host2, port2);
printf(" Recv %5d bytes %16s:%d
", read2, host2, port2);
makelog(tmpbuf, strlen(tmpbuf));
makelog(read_in2, read2);
totalread2 += read2;
memset(read_in2, 0, MAXSIZE);
}
}
if (FD_ISSET(fd1, &writefd))
{
int err2 = 0;
sendcount2 = 0;
while (totalread2>0)
{
send2 = send(fd1, send_out2 + sendcount2, totalread2, 0);
if (send2 == 0)break;
if ((send2<0) && (errno != EINTR))
{
printf("[-] Send to fd1 unknow error.
");
err2 = 1;
break;
}
if ((send2<0) && (errno == ENOSPC)) break;
sendcount2 += send2;
totalread2 -= send2;
printf(" Send %5d bytes %16s:%d
", send2, host1, port1);
}
if (err2 == 1) break;
if ((totalread2>0) && (sendcount2 > 0))
{
/* move not sended data to start addr */
memcpy(send_out2, send_out2 + sendcount2, totalread2);
memset(send_out2 + totalread2, 0, MAXSIZE - totalread2);
}
else
memset(send_out2, 0, MAXSIZE);
}
Sleep(5);
}
closesocket(fd1);
closesocket(fd2);
// if(method == 3)
// connectnum --;
printf("
[+] OK! I Closed The Two Socket.
");
}
void getctrlc(int j)
{
printf("
[-] Received Ctrl+C
");
closeallfd();
exit(0);
}
void closeallfd()
{
int i;
printf("[+] Let me exit ......
");
fflush(stdout);
for (i = 3; i<256; i++)
{
closesocket(i);
}
if (fp != NULL)
{
fprintf(fp, "
====== Exit ======
");
fclose(fp);
}
printf("[+] All Right!
");
}
int create_socket()
{
int sockfd;
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd<0)
{
printf("[-] Create socket error.
");
return(0);
}
return(sockfd);
}
int create_server(int sockfd, int port)
{
struct sockaddr_in srvaddr;
int on = 1;
memset(&srvaddr, 0, sizeof(struct sockaddr));
srvaddr.sin_port = htons(port);
srvaddr.sin_family = AF_INET;
srvaddr.sin_addr.s_addr = htonl(INADDR_ANY);
setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (char*)&on, sizeof(on)); //so I can rebind the port
if (bind(sockfd, (struct sockaddr *)&srvaddr, sizeof(struct sockaddr))<0)
{
printf("[-] Socket bind error.
");
return(0);
}
if (listen(sockfd, CONNECTNUM)<0)
{
printf("[-] Socket Listen error.
");
return(0);
}
return(1);
}
int client_connect(int sockfd, char* server, int port)
{
struct sockaddr_in cliaddr;
struct hostent *host;
if (!(host = gethostbyname(server)))
{
printf("[-] Gethostbyname(%s) error:%s
", server, strerror(errno));
return(0);
}
memset(&cliaddr, 0, sizeof(struct sockaddr));
cliaddr.sin_family = AF_INET;
cliaddr.sin_port = htons(port);
cliaddr.sin_addr = *((struct in_addr *)host->h_addr);
if (connect(sockfd, (struct sockaddr *)&cliaddr, sizeof(struct sockaddr))<0)
{
printf("[-] Connect error.
");
return(0);
}
return(1);
}
void makelog(char *buffer, int length)
{
if (fp != NULL)
{
_write(_fileno(fp), buffer, length);
}
}
注意，VS2013编译出来的程序在其他计算机上运行时，可能出现如下问题：
这是由于需要MSVCR120.dll这个动态链接库来支持C函数库和C++的STL标准库。对于这个问题的解决方法是：可以把C/C++运行时库MSVCR120编译到你的exe里，这样你的程序复制到任意windows上就能直接运行了。项目 - 属性 - 配置属性 - C/C++ - 代码生成 - 运行库 - 多线程(/MT)。这样生成的EXE会增大一些，取决于你用到了多少库函数。具体设置如下图所示：
最后，附上效果图一张：
采用这种方式进行端口转发，其实速度有些慢，有时候会比较卡。对于Web端口转发工具及HTTP版本的LCX，后续我再分析一下。
以上源码仅供学习之用，请不要用于非法途径。
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