其他

开发平台：
Delphi

ProxySocket.pas：源码内容
							unit ProxySocket;
{$define SYNC}
{
UDP Proxy core unit
copyright (C) 2000-2002 NetGale
}
interface
uses SysUtils,WIndows,WinSock,Classes,Dialogs;
type
    TProxySock=class;
    TProxyReadThread=class(TThread)
        private
        FProxySock:TProxySock;
        FBuffer:array [0..2048] of char;
        FBuflen:Integer;
        FFromAddr:TSockAddr;
        procedure DoNotify;
        protected
        procedure DoTerminate; override;
        procedure Execute; override;
        public
        constructor Create(CreateSuspended:Boolean;ASock:TProxySock);
        destructor  Destroy;override;
        end;
    TSwitchDirection=(sdRecv,sdSend);
    TSockNotifyEvent=procedure (buf:array of char;buflen:integer;from:TSockAddr;Dest:TSockAddr;var drop:Boolean) of object;
    TUDPSwitcher=class;
    PUDPSwitcher=^TUDPSwitcher;
    TProxySock=class
        private
        FDirection:TSwitchDirection;
        FSocket:TSocket;
        FReadThread:TProxyReadThread;
        FSwitcher:TUDPSwitcher;
        procedure   Init;
        public
        Tag:Integer;
        ThisAddr,ProxyAddr:TSockAddr;
        constructor Create(aProxyAddr:TSockAddr);overload;
        constructor Create(aThisAddr:TSockAddr;aProxyAddr:TSockAddr);overload;
        constructor Create(ThisPort:WORD;aProxyAddr:TSockAddr);overload;
        constructor Create(ThisPort:WORD;ProxyIp:String;ProxyPort:WORD);overload;
        destructor  Destroy;override;
        function    CreateSocket:Boolean;
        procedure   OnRecv(buf:array of char;buflen:Integer;from:TSockAddr);
        function    SendBuf(buf:array of char;buflen:Integer;Dest:TSockAddr):Boolean;overload;
        function    SendBuf(buf:array of char;buflen:Integer;DestIp:String;DestPort:Word):Boolean;overload;
        function    StartThread:Boolean;
        procedure   StopThread;
        end;
    PProxySock=^TProxySock;
    TUDPSwitcher=class
        private
        FSockets:array of TProxySock;
        FInternalFlag:array of boolean;
        FOnSend: TSockNotifyEvent;
        FOnRecv: TSockNotifyEvent;
        FOnNewSocket: TNotifyEvent;
{$ifdef SYNC}
        FSockLock:TMultiReadExclusiveWriteSynchronizer;
{$endif}
        FInternalProxyCount: Integer;
        FExternalProxyCount: Integer;
        procedure SetOnRecv(const Value: TSockNotifyEvent);
        procedure SetOnSend(const Value: TSockNotifyEvent);
        procedure SetOnNewSocket(const Value: TNotifyEvent);
        function  GetSocketByDirection(index:integer;direction:TSwitchDirection):TProxySock;
        public
        property  OnNewSocket:TNotifyEvent read FOnNewSocket write SetOnNewSocket;
        property  OnRecv:TSockNotifyEvent read FOnRecv write SetOnRecv;
        property  OnSend:TSockNotifyEvent read FOnSend write SetOnSend;
        property  InternalProxyCount:Integer read FInternalProxyCount;
        property  ExternalProxyCount:Integer read FExternalProxyCount;
        function  RegisterSocket(sock:TProxySock;Direction:TSwitchDirection;InternalFlag:Boolean=false):Integer;
        procedure UnregisterSocket(sock:TProxySock);
        function  FindSocket(addr:TSockAddr):TProxySock;overload;
        function  FindSocket(ip:String;port:WORD):TProxySock;overload;
        function  FindSocketByTag(tag:Integer):TProxySock;
        function  GetInternalProxy(index:Integer):TProxySock;
        function  GetExternalProxy(index:Integer):TProxySock;
        procedure SwitchPackage(buf:array of char;buflen:Integer;from:TSockAddr;Dest:TSockAddr;hint:TSwitchDirection);
        constructor Create(primary:TProxySock);overload;
        constructor Create(thisPort:Word;proxyAddr:String;proxyPort:Word);overload;
        destructor  Destroy;override;
        function  GetPrimarySocket:TProxySock;
        end;
implementation
uses IpHdr;
{ TProxySock }
constructor TProxySock.Create(aThisAddr, aProxyAddr: TSockAddr);
begin
Init;
ThisAddr:=aThisAddr;
ProxyAddr:=aProxyAddr;
end;
constructor TProxySock.Create(aProxyAddr: TSockAddr);
begin
Init;
ThisAddr.sin_family:=AF_INET;
ThisAddr.sin_addr.S_addr:=INADDR_ANY;
ThisAddr.sin_port:=0;
ProxyAddr:=aProxyAddr;
CreateSocket;
end;
constructor TProxySock.Create(ThisPort: WORD; ProxyIp: String;
  ProxyPort: WORD);
begin
Init;
ThisAddr.sin_family:=AF_INET;
ThisAddr.sin_addr.S_addr:=INADDR_ANY;
ThisAddr.sin_port:=htons(ThisPort);
ProxyAddr.sin_family:=AF_INET;
ProxyAddr.sin_port:=htons(ProxyPort);
LookupName(proxyIp,ProxyAddr.sin_addr);
CreateSocket;
end;
constructor TProxySock.Create(ThisPort: WORD; aProxyAddr: TSockAddr);
begin
Init;
ThisAddr.sin_family:=AF_INET;
ThisAddr.sin_port:=htons(ThisPort);
ThisAddr.sin_addr.S_addr:=INADDR_ANY;
ProxyAddr:=aProxyAddr;
CreateSocket;
end;
function TProxySock.CreateSocket: Boolean;
begin
FSocket:=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
if(FSocket<>INVALID_SOCKET)then
    begin
    if(bind(FSocket,ThisAddr,SizeOf(ThisAddr))<>SOCKET_ERROR)then
        begin
        if(not StartThread)then
            begin
            closesocket(FSocket);
            FSocket:=INVALID_SOCKET;
            Result:=False;
            end
        else Result:=TRUE;
        end
    else
        begin
        closesocket(FSocket);
        FSocket:=INVALID_SOCKET;
        Result:=False;
        end;
    end
else Result:=False;
end;
destructor TProxySock.Destroy;
begin
if(FSocket<>INVALID_SOCKET)then closesocket(FSocket);
if(Assigned(FReadThread))then FReadThread.Terminate;
if(FSwitcher<>nil)then FSwitcher.UnregisterSocket(self);
inherited;
end;
procedure TProxySock.Init;
begin
FReadThread:=nil;
FSocket:=INVALID_SOCKET;
FSwitcher:=nil;
end;
procedure TProxySock.OnRecv(buf: array of char; buflen: Integer;
  from: TSockAddr);
var
drop:Boolean;
begin
drop:=False;
case FDirection of
    sdSend:
        begin
        if(Assigned(FSwitcher) and Assigned(FSwitcher.FOnSend))then
            FSwitcher.FOnSend(buf,buflen,from,ProxyAddr,drop);
        end;
    sdRecv:
        begin
        if(Assigned(FSwitcher)and Assigned(FSwitcher.FOnRecv))then
            FSwitcher.FOnRecv(buf,buflen,from,ProxyAddr,drop);
        end;
    end;
if((not drop) and (FSwitcher<>nil))then
    begin
    FSwitcher.SwitchPackage(buf,buflen,from,ProxyAddr,FDirection);
    end;
end;
function TProxySock.SendBuf(buf: array of char; buflen: Integer;
  Dest: TSockAddr): Boolean;
begin
if(FSocket<>INVALID_SOCKET)then
    begin
    Result:=(WinSock.sendto(FSocket,buf,buflen,0,Dest,SizeOf(Dest))<>SOCKET_ERROR);
    end
else Result:=False;
end;
function TProxySock.SendBuf(buf: array of char; buflen: Integer;
  DestIp: String; DestPort: Word): Boolean;
var
addr:TSockAddr;
begin
addr.sin_family:=AF_INET;
addr.sin_addr.S_addr:=inet_addr(PChar(DestIp));
addr.sin_port:=DestPort;
Result:=SendBuf(buf,buflen,addr);
end;
function TProxySock.StartThread: Boolean;
begin
try
    FReadThread:=TProxyReadThread.Create(False,self);
    Result:=True;
except
    Result:=False;
    end;
end;
procedure TProxySock.StopThread;
begin
FReadThread.Terminate;
end;
{ TUDPSwitcher }
constructor TUDPSwitcher.Create(primary: TProxySock);
begin
FOnRecv:=nil;
FOnSend:=nil;
{$ifdef SYNC}
FSockLock:=TMultiReadExclusiveWriteSynchronizer.Create;
{$endif}
RegisterSocket(primary,sdSend,true);
end;
constructor TUDPSwitcher.Create(thisPort: Word; proxyAddr: String;
  proxyPort: Word);
var
s:TProxySock;
begin
FOnRecv:=nil;
FOnSend:=nil;
{$ifdef SYNC}
FSockLock:=TMultiReadExclusiveWriteSynchronizer.Create;
{$endif}
s:=TProxySock.Create(thisPort,ProxyAddr,ProxyPort);
RegisterSocket(s,sdSend,true);
end;
destructor TUDPSwitcher.Destroy;
var
i,len:Integer;
begin
len:=Length(FSockets);
for i:=0 to len-1 do
    begin
    UnregisterSocket(FSockets[i]);
    end;
end;
function TUDPSwitcher.FindSocket(addr: TSockAddr): TProxySock;
var
i,len:Integer;
begin
Result:=nil;
{$ifdef SYNC}
FSockLock.BeginRead;
{$endif}
len:=Length(FSockets);
for i:=0 to len-1 do
    begin
    if((FSockets[i].ProxyAddr.sin_addr.S_addr=addr.sin_addr.S_addr)
        and(FSockets[i].ProxyAddr.sin_port=addr.sin_port)
        and(FSockets[i].ProxyAddr.sin_family=addr.sin_family))then
        begin
        Result:=FSockets[i];
        end;
    end;
{$ifdef SYNC}
FSockLock.EndRead;
{$endif}
end;
function TUDPSwitcher.FindSocket(ip: String; port: WORD): TProxySock;
var
addr:TSockAddr;
begin
addr.sin_family:=AF_INET;
addr.sin_addr.S_addr:=inet_addr(PChar(ip));
addr.sin_port:=htons(port);
Result:=FindSocket(addr);
end;
function TUDPSwitcher.FindSocketByTag(tag: Integer): TProxySock;
var
i,len:Integer;
begin
Result:=nil;
len:=Length(FSockets);
for i:=0 to len-1 do
    begin
    if(FSockets[i].Tag=tag)then
        begin
        Result:=FSockets[i];
        end;
    end;
end;
function TUDPSwitcher.GetExternalProxy(index: Integer): TProxySock;
begin
Result:=GetSocketByDirection(index,sdRecv);
end;
function TUDPSwitcher.GetInternalProxy(index: Integer): TProxySock;
begin
Result:=GetSocketByDirection(index,sdSend);
end;
function TUDPSwitcher.GetPrimarySocket: TProxySock;
begin
Result:=FSockets[0];
end;
function TUDPSwitcher.GetSocketByDirection(index: integer;
  direction: TSwitchDirection): TProxySock;
var
cnt,i,len:Integer;
begin
Result:=nil;
cnt:=0;
len:=Length(FSockets);
for i:=0 to len-1 do
    begin
    if(FSockets[i].FDirection=direction)then
        begin
        if(cnt=index)then
            begin
            Result:=FSockets[i];
            Break;
            end;
        Inc(cnt);
        end;
    end;
end;
function TUDPSwitcher.RegisterSocket(sock: TProxySock;Direction:TSwitchDirection;InternalFlag:Boolean=false):Integer;
var
len,i:Integer;
begin
Result:=-1;
{$ifdef SYNC}
FSockLock.BeginWrite;
{$endif}
sock.FSwitcher:=self;
sock.FDirection:=Direction;
len:=Length(FSockets);
for i:=0 to len-1 do
    begin
    if(FSockets[i]=nil)then
        begin
        FSockets[i]:=sock;
        FInternalFlag[i]:=InternalFlag;
        Result:=i;
        end;
    end;
if(Result=-1)then
    begin
    SetLength(FSockets,len+1);
    SetLength(FInternalFlag,len+1);
    FSockets[len]:=sock;
    FInternalFlag[len]:=InternalFlag;
    Result:=len;
    end;
{$ifdef SYNC}
FSockLock.EndWrite;
{$endif}
end;
procedure TUDPSwitcher.SetOnNewSocket(const Value: TNotifyEvent);
begin
  FOnNewSocket := Value;
end;
procedure TUDPSwitcher.SetOnRecv(const Value: TSockNotifyEvent);
begin
  FOnRecv := Value;
end;
procedure TUDPSwitcher.SetOnSend(const Value: TSockNotifyEvent);
begin
  FOnSend := Value;
end;
procedure TUDPSwitcher.SwitchPackage(buf: array of char; buflen: Integer;
  from, Dest: TSockAddr;hint:TSwitchDirection);
var
sock:TProxySock;
begin
sock:=FindSocket(from);
if(sock=nil)then
    begin
    if(hint=sdSend)then hint:=sdRecv
    else hint:=sdSend;
    sock:=TProxySock.Create(from);
    if(sock<>nil)then
        begin
        RegisterSocket(sock,hint,true);
        if(Assigned(OnNewSocket))then  OnNewSocket(sock);
        end;
    end;
sock.SendBuf(buf,buflen,Dest);
end;
procedure TUDPSwitcher.UnregisterSocket(sock: TProxySock);
var
i,len:Integer;
begin
{$ifdef SYNC}
FSockLock.BeginWrite;
{$endif}
len:=Length(FSockets);
sock.FSwitcher:=nil;
for i:=0 to len-1 do
    begin
    if(FSockets[i]=sock)then
        begin
        if(FInternalFlag[i])then sock.Destroy;
        FSockets[i]:=nil;
        Break;
        end;
    end;
{$ifdef SYNC}
FSockLock.EndWrite;
{$endif}
end;
{ TProxyReadThread }
constructor TProxyReadThread.Create(CreateSuspended: Boolean;
  ASock: TProxySock);
begin
FreeOnTerminate := True;
FProxySock:=ASock;
inherited Create(CreateSuspended);
end;
destructor TProxyReadThread.Destroy;
begin
inherited;
end;
procedure TProxyReadThread.DoNotify;
begin
if(Assigned(FProxySock))then
    FProxySock.OnRecv(FBuffer,FBuflen,FFromAddr);
end;
procedure TProxyReadThread.DoTerminate;
begin
  inherited;
if(Assigned(FProxySock)
    and Assigned(FProxySock.FReadThread)
    and (FProxySock.FReadThread=self))then
    begin
    FProxySock.FReadThread:=nil;
    end;
end;
procedure TProxyReadThread.Execute;
var
fromlen:Integer;
begin
while((not Terminated) and Assigned(FProxySock))do
    begin
    fromlen:=sizeof(FFromAddr);
    FBufLen:=recvfrom(FProxySock.FSocket,FBuffer,2048,0,FFromAddr,fromlen);
    if(FBuflen<>SOCKET_ERROR)then
        begin
        Synchronize(DoNotify);
        end;
    end;
end;
end.

						