本文以实例形式讲述了Delphi下木马的文件传输方法的实现过程，具体步骤如下：
服务器端代码:
unit ServerFrm;
interfaceuses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, ComCtrls, StdCtrls, ExtCtrls,WinSock;
type TfrmMain = class(TForm) Panel1: TPanel;
Label1: TLabel;
edtPort: TEdit;
Panel2: TPanel;
stabar: TStatusBar;
SaveDialog: TSaveDialog;
btnListen: TButton;
btnReceive: TButton;
btnStop: TButton;
btnExit: TButton;
procedure FormCreate(Sender: TObject);
procedure btnExitClick(Sender: TObject);
procedure FormClose(Sender: TObject;
var Action: TCloseAction);
procedure btnListenClick(Sender: TObject);
procedure btnReceiveClick(Sender: TObject);
procedure btnStopClick(Sender: TObject);
private {
Private declarations }
public {
Public declarations }
StopTrans:Boolean;
//是否停止传送开关 InTrans:Boolean;
//表示正在接收文件 Server:TSocket;
//定义服务器端的socket句柄 //自定义过程接收文件 procedure RecvFile(FileName:String);
end;
var frmMain: TfrmMain;
const BlockLen=1024*4;
implementation{
$R *.dfm}
procedure tfrmmain.RecvFile(FileName:String);
var Ftrans:file of Byte;
Recelen:Integer;
Blockbuf:array[0..BlockLen-1] of Byte;
RecvSocket:TSocket;
ra:Sockaddr_in;
ra_len:integer;
begin ra_len:=sizeof(ra);
Recvsocket:=accept(server,@ra,@ra_len);
assignFile(Ftrans,filename);
rewrite(ftrans);
stoptrans:=false;
intrans:=true;
recelen:=recv(recvsocket,Blockbuf,BlockLen,0);
while (recelen>0) and (not StopTrans) do begin BlockWrite(Ftrans,Blockbuf[0],BlockLen);
application.ProcessMessages;
recelen:=recv(recvsocket,Blockbuf,Blocklen,0);
if stoptrans then begin CloseFile(Ftrans);
CloseSocket(RecvSocket);
InTrans:=False;
MessageBox(Handle,'停止传输!','提示',MB_OK);
EXIT;
END;
END;
//关闭文件,接收的SOCKET CloseFile(Ftrans);
Closesocket(recvsocket);
InTrans:=False;
if (Recelen=SOCKET_ERROR) then messagebox(handle,'传输异常终止!','提示',MB_OK) ELSE MESSAGEBOX(HANDLE,'客户端已经关闭连接1,文件可能已经传送完毕了!','提示',MB_OK);
end;
procedure TfrmMain.FormCreate(Sender: TObject);
var aWSAData:TWSAData;
begin if WSAStartup($0101,aWSAData)<>0 then raise Exception.Create('不能启动WinSock动态链接库');
messageBox(Handle,aWSAdata.szDescription ,'WinSock动态链接库版本',mb_ok);
end;
procedure TfrmMain.btnExitClick(Sender: TObject);
begin Close;
end;
procedure TfrmMain.FormClose(Sender: TObject;
var Action: TCloseAction);
begin if InTrans then if MessageBox(handle,'正在接收文件,停止吗？','提示',MB_YESNO)=IDNO then abort;
IF SERVER<>INVALID_SOCKET THEN CLOSESOCKET(SERVER);
//释放winsock动态链接库所创建的资源 if WSACleanup<>0 then messagebox(handle,'清除Winsock动态链接库错误！','提示',MB_OK) ELSE messagebox(handle,'清除Winsock动态链接库成功！','提示',MB_OK);
end;
procedure TfrmMain.btnListenClick(Sender: TObject);
var ca:SOCKADDR_IN;
begin //创建服务器端SOCKET Server:=Socket(PF_INET,SOCK_STREAM,IPPROTO_IP);
IF server=invalid_socket then begin stabar.SimpleText :='创建接收SOCKET错误1';
exit;
end;
//绑定服务器端SOCKET ca.sin_family :=PF_INET;
CA.sin_port :=htons(strtoint(trim(edtPort.Text )));
ca.sin_addr.S_addr :=INADDR_ANY;
if bind(server,ca,sizeof(ca))=socket_error then begin stabar.SimpleText :='绑定socket错误,请更改接收端口';
closeSocket(server);
exit;
end else stabar.SimpleText :='绑定接收端socket成功!';
//开始监听 listen(server,5);
btnlisten.Enabled :=False;
btnstop.Enabled :=true;
end;
procedure TfrmMain.btnReceiveClick(Sender: TObject);
begin if (server=INVALID_SOCKET) THEN BEGIN MESSAGEBOX(HANDLE,'还没有进行监听,请先进行监听!','提示',MB_OK);
EXIT;
END;
IF SaveDialog.Execute THEN RECVFILE(SaveDialog.FileName );
end;
procedure TfrmMain.btnStopClick(Sender: TObject);
begin STOPTRANS:=TRUE;
IF SERVER<>INVALID_SOCKET THEN cLOSESOCKET(SERVER);
//此处需要说明 server:=INVALID_SOCKET;
bTNSTOP.Enabled :=fALSE;
BTNlISTEN.Enabled :=TRUE;
end;
end.
客户端代码:
unit ClientFrm;
interfaceuses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls, ComCtrls,WinSock;
type TfrmMain = class(TForm) opendfile: TOpenDialog;
Label1: TLabel;
edtIP: TEdit;
Label2: TLabel;
edtPort: TEdit;
StatusBar: TStatusBar;
btnConnect: TButton;
btnSend: TButton;
btnStop: TButton;
btnExit: TButton;
ProgressBar: TProgressBar;
procedure FormCreate(Sender: TObject);
procedure btnExitClick(Sender: TObject);
procedure FormClose(Sender: TObject;
var Action: TCloseAction);
procedure btnConnectClick(Sender: TObject);
procedure btnSendClick(Sender: TObject);
procedure btnStopClick(Sender: TObject);
private {
Private declarations }
Client:TSocket;
public {
Public declarations }
StopTrans:Boolean;
//是否停止发送的开发 InTrans:Boolean;
//表示是否正在传送文件 procedure TransFile(FileName:String);
//传递文件的过程 end;
const BlockLen=1024*4;
//每次发送的最大数据量var frmMain: TfrmMain;
implementation{
$R *.dfm}
procedure TfrmMain.TransFile(FileName:String);
//传递文件的过程var Ftrans:file of Byte;
Flen:integer;
BlockNum,RemainLen:integer;
BlockBuf:array[0..BlockLen-1] of Byte;
i:integer;
SendLen:Integer;
begin assignFile(Ftrans,filename);
reset(Ftrans);
Flen:=FileSize(Ftrans);
BlockNum:=Flen div BlockLen;
progressBar.Max :=1+BlockNum;
RemainLen:=Flen mod BlockLen;
StopTrans:=False;
InTrans:=True;
SendLen:=1;
for i:=0 to BlockNum-1 do begin if (StopTrans) or (SendLen<=0) then Break;
BlockRead(Ftrans,Blockbuf[0],BlockLen);
SendLen:=Send(Client,Blockbuf,BlockLen,0);
ProgressBar.Position :=i;
Application.processMessages;
end;
if StopTrans then begin CloseFile(Ftrans);
InTrans:=False;
StatusBar.SimpleText :='';
MessageBox(Handle,'停止传输!','提示',mb_ok);
progressbar.Position :=0;
exit;
end;
if (SendLen<=0) then begin CloseFile(Ftrans);
InTrans:=False;
StatusBar.SimpleText :='';
messagebox(handle,'传出异常终止!','提示',MB_OK);
progressBar.Position :=0;
exit;
end;
if remainLen>0 then begin BlockRead(Ftrans,BlockBuf[0],RemainLen);
SendLen:=send(client,BlockBuf,Remainlen,0);
if (sendLen<=0) then begin closeFile(Ftrans);
InTrans:=False;
StatusBar.SimpleText :='';
messagebox(handle,'传输异常终止!','提示',mb_ok);
progressBar.Position :=0;
exit;
end;
end;
progressBar.Position :=ProgressBar.Max ;
CloseFile(Ftrans);
InTrans:=False;
StatusBar.SimpleText :='';
messagebox(handle,'传输完成!','提示',mb_ok);
progressbar.Position :=0;
end;
procedure TfrmMain.FormCreate(Sender: TObject);
var aWSAData:TWSAData;
begin if WSAStartup($0101,aWSAData)<>0 then raise Exception.Create('不能启动WinSock动态链接库');
messageBox(Handle,aWSAdata.szDescription ,'WinSock动态链接库版本',mb_ok);
end;
procedure TfrmMain.btnExitClick(Sender: TObject);
begin Close;
end;
procedure TfrmMain.FormClose(Sender: TObject;
var Action: TCloseAction);
begin if InTrans then if MessageBox(handle,'正在传输文件,停止吗？','提示',MB_YESNO)=IDNO then abort;
//释放winsock动态链接库所创建的资源 if WSACleanup<>0 then messagebox(handle,'清除Winsock动态链接库错误！','提示',MB_OK) ELSE messagebox(handle,'清除Winsock动态链接库成功！','提示',MB_OK);
CloseSocket(Client);
end;
procedure TfrmMain.btnConnectClick(Sender: TObject);
var ca:SOCKADDR_IN;
hostaddr:u_long;
begin Client:=Socket(PF_INET,SOCK_STREAM,IPPROTO_IP);
IF CLIENT=INVALID_SOCKET THEN BEGIN StatusBar.SimpleText :='为连接远程服务器端创建COSKET错误!';
exit;
end;
ca.sin_family :=PF_INET;
CA.sin_port :=HTONS(STRTOINT(TRIM(EDTpORT.Text )));
HOSTADDR:=INET_ADDR(PCHAR(TRIM(EDTIP.Text )));
//判断IP是否合法 if (hostaddr= -1) then begin StatusBar.SimpleText :='主机IP地址：'+trim(edtip.Text )+'错误';
exit;
end else ca.sin_addr.S_addr :=hostaddr;
//连接服务器 if connect(Client,ca,sizeof(ca))<>0 then begin StatusBar.SimpleText :='连接服务器端SOCKET错误!';
exit;
end else StatusBar.SimpleText :='连接远程SOCKET成功!';
end;
procedure TfrmMain.btnSendClick(Sender: TObject);
begin if (opendfile.Execute ) and (FileExists(opendfile.FileName )) then transFile(opendfile.FileName );
end;
procedure TfrmMain.btnStopClick(Sender: TObject);
begin Stoptrans:=True;
end;
end.
