代理上网是怎样实现?愿给出原码。 那种通过浏览器设置代理上网和通过代理服务器上网 是怎么实现的? 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 用VC++6.0编写Proxy服务器(转) 我们一般常用的Internet代理服务器是用微软的Proxy Server 2.0 。但我们可以自己动手编写一个简单、小型的Proxy Server 。下面介绍具体的实现方法。 一. 原理 本程序的结构原理如下: 对于每一个用户的请求(Internet 请求,由浏览器发出),本程序将启动两个线程,一个把本地用户的请求数据发送到远程的Internet主机,另一个线程把远程主机的回应数据发送到本地请求用户。 二. 主要函数 UserToProxyThread ( void * pParam ): 它是用来把本地用户请求数据发送到远程主机的,起服务器线程角色。当接到本地(局域网)用户的请求,它就启动另一个自身线程,以侦听别的用户的请求,并读出已接收到的请求数据,接着启动第二个线程ProxyToServer()(这个线程用来连接远程主机),当远程主机连接成功后,它把已读出的本地用户请求数据发送到远程主机。 ProxyToServer ( void * pParam): 可以被当作是客户端服务,它把远程主机发送来的数据分发给本地请求用户。 三. 开发运行环境 本程序是在VC++6.0环境下开发的,在Win95 和 WinNT4.0下运行正常。 四. 详细代码#include "stdafx.h"#include "Proxy.h"#include < winsock2.h > //WINSOCKET API 2。0#include < stdlib.h >#include < stdio.h >#include < string.h >#ifdef _DEBUG#define new DEBUG_NEW#undef THIS_FILEstatic char THIS_FILE[] = __FILE__;#endif////////////////////////////////////////////////////////////////#define HTTP "http://"#define FTP "ftp://"#define PROXYPORT 5001 //Proxy 端口#define BUFSIZE 10240 //缓冲区大小CWinApp theApp;using namespace std;UINT ProxyToServer(LPVOID pParam);UINT UserToProxyThread(void *pParam);struct SocketPair{ SOCKET user_proxy; //socket : 本地机器到PROXY 服务机 SOCKET proxy_server; //socket : PROXY 服务机到远程主机 BOOL IsUser_ProxyClosed; // 本地机器到PROXY 服务机状态 BOOL IsProxy_ServerClosed; // PROXY 服务机到远程主机状态};struct ProxyParam{ char Address[256]; // 远程主机地址 HANDLE User_SvrOK; // PROXY 服务机到远程主机的联结状态 SocketPair *pPair; // 维护一组SOCKET的指针 int Port; // 用来联结远程主机的端口}; //这个结构用来PROXY SERVER与远程主机的信息交换.SOCKET gListen_Socket; //用来侦听的SOCKET。int StartServer() //启动服务{ WSADATA wsaData; sockaddr_in local; SOCKET listen_socket; if(::WSAStartup(0x202,&wsaData)!=0) { printf("\nError in Startup session.\n"); WSACleanup(); return -1; } local.sin_family=AF_INET; local.sin_addr.s_addr=INADDR_ANY; local.sin_port=htons(PROXYPORT); listen_socket=socket(AF_INET,SOCK_STREAM,0); if(listen_socket==INVALID_SOCKET) { printf("\nError in New a Socket."); WSACleanup(); return -2; } if(::bind(listen_socket,(sockaddr *)&local,sizeof(local))!=0) { printf("\n Error in Binding socket."); WSACleanup(); return -3; } if(::listen(listen_socket,5)!=0) { printf("\n Error in Listen."); WSACleanup(); return -4; } gListen_Socket=listen_socket; AfxBeginThread(UserToProxyThread,NULL); //启动侦听return 1;} int CloseServer() //关闭服务{closesocket(gListen_Socket); WSACleanup(); return 1;}//分析接收到的字符,得到远程主机地址int GetAddressAndPort( char * str, char *address, int * port){ char buf[BUFSIZE], command[512], proto[128], *p; int j; sscanf(str,"%s%s%s",command,buf,proto); p=strstr(buf,HTTP); //HTTP if(p) { p+=strlen(HTTP); for(int i=0;i< strlen(p);i++) if( *(p+i)==`/`) break; *(p+i)=0; strcpy(address,p); p=strstr(str,HTTP); for(int j=0;j< i+strlen(HTTP);j++) *(p+j)=` `; //去掉远程主机%C 补上面的:// 取到本地的数据,发往远程主机UINT UserToProxyThread(void *pParam){ char Buffer[BUFSIZE]; int Len; sockaddr_in from; SOCKET msg_socket; int fromlen,retval; SocketPair SPair; ProxyParam ProxyP; CWinThread *pChildThread; fromlen=sizeof(from); msg_socket=accept(gListen_Socket,(struct sockaddr*)&from,&fromlen); AfxBeginThread(UserToProxyThread,pParam); //启动另一侦听. if( msg_socket==INVALID_SOCKET) { printf( "\nError in accept "); return -5; } //读客户的第一行数据 SPair.IsUser_ProxyClosed=FALSE; SPair.IsProxy_ServerClosed=TRUE; SPair.user_proxy=msg_socket; retval=recv(SPair.user_proxy,Buffer,sizeof(Buffer),0); if(retval==SOCKET_ERROR) { printf("\nError Recv"); if(SPair.IsUser_ProxyClosed==FALSE) { closesocket(SPair.user_proxy); SPair.IsUser_ProxyClosed=TRUE; } } if(retval==0) { printf("Client Close connection\n"); if(SPair.IsUser_ProxyClosed==FALSE) { closesocket(SPair.user_proxy); SPair.IsUser_ProxyClosed=TRUE; } } Len=retval; #ifdef _DEBUG Buffer[Len]=0; printf("\n Received %d bytes,data[%s]from client\n",retval,Buffer); #endif // SPair.IsUser_ProxyClosed=FALSE; SPair.IsProxy_ServerClosed=TRUE; SPair.user_proxy=msg_socket; ProxyP.pPair=&SPair; ProxyP.User_SvrOK=CreateEvent(NULL,TRUE,FALSE,NULL); GetAddressAndPort( Buffer,ProxyP.Address,&ProxyP.Port); pChildThread=AfxBeginThread(ProxyToServer,(LPVOID)&ProxyP); ::WaitForSingleObject(ProxyP.User_SvrOK,60000); //等待联结 ::CloseHandle(ProxyP.User_SvrOK); while(SPair.IsProxy_ServerClosed ==FALSE && SPair.IsUser_ProxyClosed==FALSE) { retval=send(SPair.proxy_server,Buffer,Len,0); if(retval==SOCKET_ERROR) { printf("\n send() failed:error%d\n",WSAGetLastError()); if(SPair.IsProxy_ServerClosed==FALSE) { closesocket(SPair.proxy_server); SPair.IsProxy_ServerClosed=TRUE; } continue; } retval=recv(SPair.user_proxy,Buffer,sizeof(Buffer),0); if(retval==SOCKET_ERROR) { printf("\nError Recv"); if(SPair.IsUser_ProxyClosed==FALSE) { closesocket(SPair.user_proxy); SPair.IsUser_ProxyClosed=TRUE; } continue; } if(retval==0) { printf("Client Close connection\n"); if(SPair.IsUser_ProxyClosed==FALSE) { closesocket(SPair.user_proxy); SPair.IsUser_ProxyClosed=TRUE; } break; } Len=retval; #ifdef _DEBUG Buffer[Len]=0; printf("\n Received %d bytes,data[%s]from client\n",retval,Buffer); #endif } //End While if(SPair.IsProxy_ServerClosed==FALSE) { closesocket(SPair.proxy_server); SPair.IsProxy_ServerClosed=TRUE; } if(SPair.IsUser_ProxyClosed==FALSE) { closesocket(SPair.user_proxy); SPair.IsUser_ProxyClosed=TRUE; } ::WaitForSingleObject(pChildThread- >m_hThread,20000); //Should check the return value return 0;}// 读取远程主机数据,并发往本地客户机UINT ProxyToServer(LPVOID pParam){ ProxyParam * pPar=(ProxyParam*)pParam; char Buffer[BUFSIZE]; char *server_name= "localhost"; unsigned short port ; int retval,Len; unsigned int addr; int socket_type ; struct sockaddr_in server; struct hostent *hp; SOCKET conn_socket; socket_type = SOCK_STREAM; server_name = pPar- >Address; port = pPar- >Port; if (isalpha(server_name[0])) { /* server address is a name */ hp = gethostbyname(server_name); } else { /* Convert nnn.nnn address to a usable one */ addr = inet_addr(server_name); hp = gethostbyaddr((char *)&addr,4,AF_INET); } if (hp == NULL ) { fprintf(stderr, "Client: Cannot resolve address [%s]: Error %d\n", server_name, WSAGetLastError()); ::SetEvent(pPar- >User_SvrOK); return 0; } // // Copy the resolved information into the sockaddr_in structure // memset(&server,0,sizeof(server)); memcpy(&(server.sin_addr),hp- >h_addr,hp- >h_length); server.sin_family = hp- >h_addrtype; server.sin_port = htons(port); conn_socket = socket(AF_INET,socket_type,0); /* 打开一个 socket */ if (conn_socket < 0 ) { fprintf(stderr, "Client: Error Opening socket: Error %d\n", WSAGetLastError()); pPar- >pPair- >IsProxy_ServerClosed=TRUE; ::SetEvent(pPar- >User_SvrOK); return -1; } #ifdef _DEBUG printf("Client connecting to: %s\n",hp- >h_name); #endif if (connect(conn_socket,(struct sockaddr*)&server,sizeof(server)) == SOCKET_ERROR) { fprintf(stderr,"connect() failed: %d\n",WSAGetLastError()); pPar- >pPair- >IsProxy_ServerClosed=TRUE; ::SetEvent(pPar- >User_SvrOK); return -1; } pPar- >pPair- >proxy_server=conn_socket; pPar- >pPair- >IsProxy_ServerClosed=FALSE; ::SetEvent(pPar- >User_SvrOK); // cook up a string to send while(!pPar- >pPair- >IsProxy_ServerClosed &&!pPar- >pPair- >IsUser_ProxyClosed) { retval = recv(conn_socket,Buffer,sizeof (Buffer),0 ); if (retval == SOCKET_ERROR ) { fprintf(stderr,"recv() failed: error %d\n",WSAGetLastError()); closesocket(conn_socket); pPar- >pPair- >IsProxy_ServerClosed=TRUE; break; } Len=retval; if (retval == 0) { printf("Server closed connection\n"); closesocket(conn_socket); pPar- >pPair- >IsProxy_ServerClosed=TRUE; break; } retval = send(pPar- >pPair- >user_proxy,Buffer,Len,0); if (retval == SOCKET_ERROR) { fprintf(stderr,"send() failed: error %d\n",WSAGetLastError()); closesocket(pPar- >pPair- >user_proxy); pPar- >pPair- >IsUser_ProxyClosed=TRUE; break; } #ifdef _DEBUG Buffer[Len]=0; printf("Received %d bytes, data [%s] from server\n",retval,Buffer); #endif } if(pPar- >pPair- >IsProxy_ServerClosed==FALSE) { closesocket(pPar- >pPair- >proxy_server); pPar- >pPair- >IsProxy_ServerClosed=TRUE; } if(pPar- >pPair- >IsUser_ProxyClosed==FALSE) { closesocket(pPar- >pPair- >user_proxy); pPar- >pPair- >IsUser_ProxyClosed=TRUE; } return 1;}int _tmain(int argc, TCHAR* argv[], TCHAR* envp[]){ int nRetCode = 0; // 初始化SOCKET if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0)) { // 错误处理 cerr < < _T("Fatal Error: MFC initialization failed") < < endl; nRetCode = 1; } else { // 主程序开始. StartServer(); while(1) if(getchar()=='q') break; CloseServer(); } return nRetCode;} 图片加载不正常是什么原因呢? 求助:关于对vector重新赋值问题。 高难度:分割状态条 IWebBrowser2 的指针,能指向一个iframe么?怎么做到? 急救时间格式化问题!! 奇怪的映射模式! 关于头文件的引用 谁有Windows CE.Net 的CD Key. 文档都写些什么? 又见操作符重载,高分请教 30岁程序员的薪水 请问如何用wininet通过有认证的代理服务器访问http?
我们一般常用的Internet代理服务器是用微软的Proxy Server 2.0 。但我们可以自己动手编写一个简单、小型的Proxy Server 。下面介绍具体的实现方法。
一. 原理 本程序的结构原理如下: 对于每一个用户的请求(Internet 请求,由浏览器发出),本程序将启动两个线程,一个把本地用户的请求数据发送到远程的Internet主机,另一个线程把远程主机的回应数据发送到本地请求用户。 二. 主要函数 UserToProxyThread ( void * pParam ): 它是用来把本地用户请求数据发送到远程主机的,起服务器线程角色。当接到本地(局域网)用户的请求,它就启动另一个自身线程,以侦听别的用户的请求,并读出已接收到的请求数据,接着启动第二个线程ProxyToServer()(这个线程用来连接远程主机),当远程主机连接成功后,它把已读出的本地用户请求数据发送到远程主机。 ProxyToServer ( void * pParam): 可以被当作是客户端服务,它把远程主机发送来的数据分发给本地请求用户。 三. 开发运行环境 本程序是在VC++6.0环境下开发的,在Win95 和 WinNT4.0下运行正常。 四. 详细代码#include "stdafx.h"#include "Proxy.h"
#include < winsock2.h > //WINSOCKET API 2。0#include < stdlib.h >
#include < stdio.h >
#include < string.h >
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
////////////////////////////////////////////////////////////////
#define HTTP "http://"
#define FTP "ftp://"
#define PROXYPORT 5001 //Proxy 端口#define BUFSIZE 10240 //缓冲区大小CWinApp theApp;using namespace std;
UINT ProxyToServer(LPVOID pParam);
UINT UserToProxyThread(void *pParam);
struct SocketPair
{
SOCKET user_proxy; //socket : 本地机器到PROXY 服务机
SOCKET proxy_server; //socket : PROXY 服务机到远程主机
BOOL IsUser_ProxyClosed; // 本地机器到PROXY 服务机状态
BOOL IsProxy_ServerClosed; // PROXY 服务机到远程主机状态
};
struct ProxyParam
{
char Address[256]; // 远程主机地址
HANDLE User_SvrOK; // PROXY 服务机到远程主机的联结状态
SocketPair *pPair; // 维护一组SOCKET的指针
int Port; // 用来联结远程主机的端口
}; //这个结构用来PROXY SERVER与远程主机的信息交换.
SOCKET gListen_Socket; //用来侦听的SOCKET。
int StartServer() //启动服务
{
WSADATA wsaData;
sockaddr_in local;
SOCKET listen_socket;
if(::WSAStartup(0x202,&wsaData)!=0)
{
printf("\nError in Startup session.\n");
WSACleanup();
return -1;
}
local.sin_family=AF_INET;
local.sin_addr.s_addr=INADDR_ANY;
local.sin_port=htons(PROXYPORT);
listen_socket=socket(AF_INET,SOCK_STREAM,0);
if(listen_socket==INVALID_SOCKET)
{
printf("\nError in New a Socket.");
WSACleanup();
return -2;
}
if(::bind(listen_socket,(sockaddr *)&local,sizeof(local))!=0)
{
printf("\n Error in Binding socket.");
WSACleanup();
return -3;
}
if(::listen(listen_socket,5)!=0)
{
printf("\n Error in Listen.");
WSACleanup();
return -4;
}
gListen_Socket=listen_socket;
AfxBeginThread(UserToProxyThread,NULL); //启动侦听return 1;}
int CloseServer() //关闭服务{closesocket(gListen_Socket);
WSACleanup();
return 1;
}
//分析接收到的字符,得到远程主机地址
int GetAddressAndPort( char * str, char *address, int * port)
{
char buf[BUFSIZE], command[512], proto[128], *p;
int j;
sscanf(str,"%s%s%s",command,buf,proto);
p=strstr(buf,HTTP);
//HTTP
if(p)
{
p+=strlen(HTTP);
for(int i=0;i< strlen(p);i++)
if( *(p+i)==`/`) break;
*(p+i)=0;
strcpy(address,p);
p=strstr(str,HTTP);
for(int j=0;j< i+strlen(HTTP);j++)
*(p+j)=` `; //去掉远程主机%C
UINT UserToProxyThread(void *pParam)
{
char Buffer[BUFSIZE];
int Len;
sockaddr_in from;
SOCKET msg_socket;
int fromlen,retval;
SocketPair SPair;
ProxyParam ProxyP;
CWinThread *pChildThread;
fromlen=sizeof(from);
msg_socket=accept(gListen_Socket,(struct sockaddr*)&from,&fromlen);
AfxBeginThread(UserToProxyThread,pParam); //启动另一侦听.
if( msg_socket==INVALID_SOCKET)
{
printf( "\nError in accept ");
return -5;
}
//读客户的第一行数据
SPair.IsUser_ProxyClosed=FALSE;
SPair.IsProxy_ServerClosed=TRUE;
SPair.user_proxy=msg_socket;
retval=recv(SPair.user_proxy,Buffer,sizeof(Buffer),0);
if(retval==SOCKET_ERROR)
{
printf("\nError Recv");
if(SPair.IsUser_ProxyClosed==FALSE)
{
closesocket(SPair.user_proxy);
SPair.IsUser_ProxyClosed=TRUE;
}
}
if(retval==0)
{
printf("Client Close connection\n");
if(SPair.IsUser_ProxyClosed==FALSE)
{
closesocket(SPair.user_proxy);
SPair.IsUser_ProxyClosed=TRUE;
}
}
Len=retval;
#ifdef _DEBUG
Buffer[Len]=0;
printf("\n Received %d bytes,data[%s]from client\n",retval,Buffer);
#endif
//
SPair.IsUser_ProxyClosed=FALSE;
SPair.IsProxy_ServerClosed=TRUE;
SPair.user_proxy=msg_socket;
ProxyP.pPair=&SPair;
ProxyP.User_SvrOK=CreateEvent(NULL,TRUE,FALSE,NULL);
GetAddressAndPort( Buffer,ProxyP.Address,&ProxyP.Port);
pChildThread=AfxBeginThread(ProxyToServer,(LPVOID)&ProxyP);
::WaitForSingleObject(ProxyP.User_SvrOK,60000); //等待联结
::CloseHandle(ProxyP.User_SvrOK);
while(SPair.IsProxy_ServerClosed ==FALSE && SPair.IsUser_ProxyClosed==FALSE)
{
retval=send(SPair.proxy_server,Buffer,Len,0);
if(retval==SOCKET_ERROR)
{
printf("\n send() failed:error%d\n",WSAGetLastError());
if(SPair.IsProxy_ServerClosed==FALSE)
{
closesocket(SPair.proxy_server);
SPair.IsProxy_ServerClosed=TRUE;
}
continue;
}
retval=recv(SPair.user_proxy,Buffer,sizeof(Buffer),0);
if(retval==SOCKET_ERROR)
{
printf("\nError Recv");
if(SPair.IsUser_ProxyClosed==FALSE)
{
closesocket(SPair.user_proxy);
SPair.IsUser_ProxyClosed=TRUE;
}
continue;
}
if(retval==0)
{
printf("Client Close connection\n");
if(SPair.IsUser_ProxyClosed==FALSE)
{
closesocket(SPair.user_proxy);
SPair.IsUser_ProxyClosed=TRUE;
}
break;
}
Len=retval;
#ifdef _DEBUG
Buffer[Len]=0;
printf("\n Received %d bytes,data[%s]from client\n",retval,Buffer);
#endif
} //End While
if(SPair.IsProxy_ServerClosed==FALSE)
{
closesocket(SPair.proxy_server);
SPair.IsProxy_ServerClosed=TRUE;
}
if(SPair.IsUser_ProxyClosed==FALSE)
{
closesocket(SPair.user_proxy);
SPair.IsUser_ProxyClosed=TRUE;
}
::WaitForSingleObject(pChildThread- >m_hThread,20000); //Should check the return value
return 0;
}
// 读取远程主机数据,并发往本地客户机
UINT ProxyToServer(LPVOID pParam)
{
ProxyParam * pPar=(ProxyParam*)pParam;
char Buffer[BUFSIZE];
char *server_name= "localhost";
unsigned short port ;
int retval,Len;
unsigned int addr;
int socket_type ;
struct sockaddr_in server;
struct hostent *hp;
SOCKET conn_socket;
socket_type = SOCK_STREAM;
server_name = pPar- >Address;
port = pPar- >Port;
if (isalpha(server_name[0]))
{
/* server address is a name */
hp = gethostbyname(server_name);
}
else
{
/* Convert nnn.nnn address to a usable one */
addr = inet_addr(server_name);
hp = gethostbyaddr((char *)&addr,4,AF_INET);
}
if (hp == NULL )
{
fprintf(stderr,
"Client: Cannot resolve address [%s]: Error %d\n",
server_name,
WSAGetLastError());
::SetEvent(pPar- >User_SvrOK);
return 0;
}
//
// Copy the resolved information into the sockaddr_in structure
//
memset(&server,0,sizeof(server));
memcpy(&(server.sin_addr),hp- >h_addr,hp- >h_length);
server.sin_family = hp- >h_addrtype;
server.sin_port = htons(port);
conn_socket = socket(AF_INET,socket_type,0); /* 打开一个 socket */
if (conn_socket < 0 )
{
fprintf(stderr,
"Client: Error Opening socket: Error %d\n",
WSAGetLastError());
pPar- >pPair- >IsProxy_ServerClosed=TRUE;
::SetEvent(pPar- >User_SvrOK);
return -1;
}
#ifdef _DEBUG
printf("Client connecting to: %s\n",hp- >h_name);
#endif
if (connect(conn_socket,(struct sockaddr*)&server,sizeof(server))
== SOCKET_ERROR)
{
fprintf(stderr,"connect() failed: %d\n",WSAGetLastError());
pPar- >pPair- >IsProxy_ServerClosed=TRUE;
::SetEvent(pPar- >User_SvrOK);
return -1;
}
pPar- >pPair- >proxy_server=conn_socket;
pPar- >pPair- >IsProxy_ServerClosed=FALSE;
::SetEvent(pPar- >User_SvrOK);
// cook up a string to send
while(!pPar- >pPair- >IsProxy_ServerClosed &&!pPar- >pPair- >IsUser_ProxyClosed)
{
retval = recv(conn_socket,Buffer,sizeof (Buffer),0 );
if (retval == SOCKET_ERROR )
{
fprintf(stderr,"recv() failed: error %d\n",WSAGetLastError());
closesocket(conn_socket);
pPar- >pPair- >IsProxy_ServerClosed=TRUE;
break;
}
Len=retval;
if (retval == 0)
{
printf("Server closed connection\n");
closesocket(conn_socket);
pPar- >pPair- >IsProxy_ServerClosed=TRUE;
break;
}
retval = send(pPar- >pPair- >user_proxy,Buffer,Len,0);
if (retval == SOCKET_ERROR)
{
fprintf(stderr,"send() failed: error %d\n",WSAGetLastError());
closesocket(pPar- >pPair- >user_proxy);
pPar- >pPair- >IsUser_ProxyClosed=TRUE;
break;
}
#ifdef _DEBUG
Buffer[Len]=0;
printf("Received %d bytes, data [%s] from server\n",retval,Buffer);
#endif
}
if(pPar- >pPair- >IsProxy_ServerClosed==FALSE)
{
closesocket(pPar- >pPair- >proxy_server);
pPar- >pPair- >IsProxy_ServerClosed=TRUE;
}
if(pPar- >pPair- >IsUser_ProxyClosed==FALSE)
{
closesocket(pPar- >pPair- >user_proxy);
pPar- >pPair- >IsUser_ProxyClosed=TRUE;
}
return 1;
}
int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
{
int nRetCode = 0;
// 初始化SOCKET
if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0))
{
// 错误处理
cerr < < _T("Fatal Error: MFC initialization failed") < < endl;
nRetCode = 1;
}
else
{
// 主程序开始.
StartServer();
while(1)
if(getchar()=='q') break;
CloseServer();
}
return nRetCode;
}