TFTP服务器接收文件

最近看到很多UDP可靠文件传输的文章，其中有提到TFTP协议，在CodeProject上面搜到一个客户端的，觉得很不错，http://www.codeproject.com/KB/IP/tftp_client.aspx

这里模仿者写了个服务器端，只实现了服务器端的接受文件，配合着基本上就可以作为一般的UDP文件接发例子了，大致代码如下

头文件：

#pragma comment(lib,"ws2_32.lib")#define TFTP_DEFAULT_PORT 69#define TFTP_OPCODE_READ 1#define TFTP_OPCODE_WRITE 2#define TFTP_OPCODE_DATA 3#define TFTP_OPCODE_ACK 4#define TFTP_OPCODE_ERROR 5#define TFTP_DEFAULT_MODE "octet"#define TFTP_DATA_PKT_SIZE 512#define TFTP_ERROR_MSG_MAX1024#define TFTP_PACKET_DATA_MAX1024#define TFTP_RETRY 3#define TFTP_RESULT_ERROR1#define TFTP_RESULT_CONTINUE 2#define TFTP_RESULT_DONE3#define TFTP_STATUS_NOTHING1#define TFTP_STATUS_GET2#define TFTP_STATUS_PUT3#define TFTP_STATUS_ERROR4#define TFTP_TIMEOUT5000 //ms,5Ãë#include <fstream>class CTFTPServer {protected:class CPacket{public:CPacket();~CPacket();bool AddByte(BYTE c);bool AddWord(WORD c);bool AddString(char* str);bool AddMem(char* mem,int len);unsigned char* GetData(int pos=0);WORD GetWord(int pos);BYTE GetByte(int pos);bool GetMem(int pos,char* mem,int len);int GetSize();void SetSize(int N);void Clear();bool IsValid();bool IsNull();bool IsACK(int blocknum);bool IsDATA(int blocknum);bool IsError();bool GetError(char* buf,unsigned int buflen);void MakeACK(int blocknum);void MakeDATA(int blocknum,char* data,int size);bool MakeWRQ(int opcode,char* filename);protected:unsigned char n_dataBuf[TFTP_PACKET_DATA_MAX];int m_nSize;};public:CTFTPServer();virtual ~CTFTPServer();bool Start(std::string strIP,USHORT nPort = TFTP_DEFAULT_PORT);bool Stop();protected:static DWORD WINAPI WorkThread(LPVOID lParam);HANDLE m_hWorkThread;private:SOCKETm_sockSvr;SOCKADDR_INm_sockAddr;SOCKADDR_INm_clientAddr;boolm_bRunning;CPacketm_packetRecv;CPacketm_packetSend;FILE*m_fileRecv;unsigned intm_nPackNum;unsigned intm_nTotalBytes;charm_chFileName[64];std::ofstreamm_logFile;void ProcessRecvData();};

实现文件：

 // TFTPServer.cpp: implementation of the CTFTPServer class.////////////////////////////////////////////////////////////////////////#include "stdafx.h"#include "TFTPServer.h"//////////////////////////////////////////////////////////////////////// TFTP packet class functions//////////////////////////////////////////////////////////////////////CTFTPServer::CPacket::CPacket(){Clear();}CTFTPServer::CPacket::~CPacket(){}unsigned char* CTFTPServer::CPacket::GetData(int pos){return &(n_dataBuf[pos]);}int CTFTPServer::CPacket::GetSize(){return m_nSize;}void CTFTPServer::CPacket::Clear(){m_nSize=0;memset(n_dataBuf,0,TFTP_PACKET_DATA_MAX);}bool CTFTPServer::CPacket::IsValid(){return (m_nSize!=-1);}bool CTFTPServer::CPacket::IsNull(){return (m_nSize == 0);}void CTFTPServer::CPacket::SetSize(int N){if ( N > TFTP_PACKET_DATA_MAX) {m_nSize =-1;} else{m_nSize =N;}}bool CTFTPServer::CPacket::AddByte(BYTE c){if (!IsValid()) return false;if (m_nSize >= TFTP_PACKET_DATA_MAX){m_nSize=-1;return false;}n_dataBuf[m_nSize] = (unsigned char)c;m_nSize++;return true;}bool CTFTPServer::CPacket::AddMem(char* mem,int len){if (!IsValid()) return false;if ( m_nSize+len>= TFTP_PACKET_DATA_MAX){m_nSize=-1;return false;}memcpy(&(n_dataBuf[m_nSize]),mem,len);m_nSize+=len;return true;}bool CTFTPServer::CPacket::AddWord(WORD c){//一个Word等于两个Byte,先存高一个Byte,再存低Byteif (!AddByte( *(((BYTE*)&c)+1) )) return false; return (!AddByte( *((BYTE*)&c) ));}bool CTFTPServer::CPacket::AddString(char* str){if ((str==NULL)||(strlen(str)==0)) return true;int n=strlen(str);for (int i=0;i<n;i++) if (!AddByte(*(str+i))) return false;return true;//AddByte(0);}bool CTFTPServer::CPacket::GetMem(int pos,char* mem,int len){if (pos>m_nSize) return false;if (len<m_nSize-pos) return false;memcpy(mem,&(n_dataBuf[pos]),m_nSize-pos);return true;}WORD CTFTPServer::CPacket::GetWord(int pos){WORD hi = GetByte(pos);WORD lo = GetByte(pos+1);return ((hi<<8)|lo);}BYTE CTFTPServer::CPacket::GetByte(int pos){return (BYTE)n_dataBuf[pos];}bool CTFTPServer::CPacket::IsACK(int blocknum){if (GetSize()!=4) return false;WORD opcode = GetWord(0);WORD block = GetWord(2);if (opcode != TFTP_OPCODE_ACK) return false;if (blocknum != block) return false;return true;}bool CTFTPServer::CPacket::IsDATA(int blocknum){if (GetSize()<4) return false;WORD opcode = GetWord(0);WORD block = GetWord(2);if (opcode != TFTP_OPCODE_DATA) return false;if (blocknum != block) return false;return true;}bool CTFTPServer::CPacket::IsError(){if (GetSize()<4) return false;WORD opcode = GetWord(0);return (opcode == TFTP_OPCODE_ERROR);}bool CTFTPServer::CPacket::GetError(char* buf,unsigned int buflen){if (!IsError()) return false;WORD errcode = GetWord(2);char* errmsg = (char*)GetData(4);if (buf==NULL) return false;if (strlen(errmsg)+10>buflen) return false;sprintf(buf,"#%i:%s",errcode,errmsg);return true;}void CTFTPServer::CPacket::MakeACK(int blocknum){Clear();AddWord(TFTP_OPCODE_ACK);AddWord(blocknum);}bool CTFTPServer::CPacket::MakeWRQ(int opcode,char* filename){ATLASSERT(filename!=NULL);if (strlen(filename)>TFTP_DATA_PKT_SIZE) return false;Clear();AddWord(opcode);AddString(filename);AddByte(0);AddString(TFTP_DEFAULT_MODE);AddByte(0);return true;}void CTFTPServer::CPacket::MakeDATA(int blocknum,char* data,int size){ATLASSERT(data!=NULL);ATLASSERT(size<=TFTP_DATA_PKT_SIZE);Clear();AddWord(TFTP_OPCODE_DATA);AddWord(blocknum);AddMem(data,size);}//////////////////////////////////////////////////////////////////////// Construction/Destruction//////////////////////////////////////////////////////////////////////CTFTPServer::CTFTPServer():m_bRunning(false),m_sockSvr(INVALID_SOCKET){::ZeroMemory(&m_sockAddr,sizeof(m_sockAddr));::ZeroMemory(m_chFileName,64);m_fileRecv = NULL;m_logFile.open("TFTPSvr.log");}CTFTPServer::~CTFTPServer(){}bool CTFTPServer::Start(std::string strIP,USHORT nPort/* = TFTP_DEFAULT_PORT*/){int nError = 0;int nRet = 0;m_sockSvr = ::socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);if(INVALID_SOCKET == m_sockSvr){nError = ::WSAGetLastError();return false;}//绑定到端口m_sockAddr.sin_family = AF_INET;m_sockAddr.sin_addr.s_addr = ::inet_addr(strIP.c_str());m_sockAddr.sin_port = ::htons(nPort);nRet = ::bind(m_sockSvr,(sockaddr*)&m_sockAddr,sizeof(m_sockAddr));if (SOCKET_ERROR == nRet){nError = ::WSAGetLastError();return false;}m_bRunning = true;m_hWorkThread = ::CreateThread(NULL,0,WorkThread,this,0,0);if (m_hWorkThread != NULL){::CloseHandle(m_hWorkThread);}return true;}bool CTFTPServer::Stop(){if (m_bRunning){m_bRunning = false;::closesocket(m_sockSvr);}return true;}DWORD WINAPI CTFTPServer::WorkThread( LPVOID lParam ){CTFTPServer *pSvr = reinterpret_cast<CTFTPServer*>(lParam);if (pSvr != NULL){while (pSvr->m_bRunning){int nRecvLen;int SenderAddrSize = sizeof(sockaddr_in);nRecvLen = recvfrom(pSvr->m_sockSvr, (char*)pSvr->m_packetRecv.GetData(), TFTP_PACKET_DATA_MAX, 0, (SOCKADDR *)&pSvr->m_clientAddr, &SenderAddrSize);pSvr->m_logFile<<"CTFTPServer::WorkThread 接收到来自"<<::inet_ntoa(pSvr->m_clientAddr.sin_addr)<<":"<<::ntohs(pSvr->m_clientAddr.sin_port)<<std::endl;if ( ( nRecvLen == 0) || (nRecvLen == WSAECONNRESET ) ) {ATLTRACE("Connection Closed./n");//break;}if ( nRecvLen == SOCKET_ERROR){ATLTRACE("recv error./n");//break;}char bufTrace[1024] = {0};::sprintf(bufTrace,"%s/n",pSvr->m_packetRecv.GetData());ATLTRACE(bufTrace);pSvr->m_packetRecv.SetSize(nRecvLen);pSvr->ProcessRecvData();//Sleep(1);}}return 0;}void CTFTPServer::ProcessRecvData(){//处理接收数据DWORD dwOpCode = m_packetRecv.GetWord(0);switch (dwOpCode){case TFTP_OPCODE_READ:{ATLTRACE("客户端下载文件/n");break;}case TFTP_OPCODE_WRITE:{//获取文件名::strcpy(m_chFileName,(const char*)m_packetRecv.GetData(2));m_packetRecv.Clear();char bufTrace[1024] = {0};::sprintf(bufTrace,"客户端上传文件:%s/n",m_chFileName);ATLTRACE(bufTrace);if( (m_fileRecv = fopen( m_chFileName, "wb" )) == NULL ){ATLTRACE("创建文件失败!/n");}//上传文件服务器确认包m_packetSend.MakeACK(0);//发送数据int nLenSended = ::sendto(m_sockSvr,(char*)m_packetSend.GetData(),m_packetSend.GetSize(),0,(SOCKADDR *)&m_clientAddr,sizeof(m_clientAddr));m_packetSend.Clear();//下一个数据序号为1m_nPackNum = 1;m_nTotalBytes = 0;break;}case TFTP_OPCODE_DATA:{DWORD dwDataNum = m_packetRecv.GetWord(2);if (m_nPackNum != dwDataNum){m_logFile<<"TFTP_OPCODE_DATA 期望数据序号:"<<m_nPackNum<<" 与发过来的不一致:"<<dwDataNum<<std::endl;break;}char bufTrace[1024] = {0};::sprintf(bufTrace,"客户端上传文件数据序号:%d/n",dwDataNum);ATLTRACE(bufTrace);char dataBuf[TFTP_DATA_PKT_SIZE] = {0};if (!m_packetRecv.GetMem(4,dataBuf,TFTP_DATA_PKT_SIZE)){ATLTRACE("复制数据错误/n");}//数据前面4个字节为opcode和packnumint nDataLen = m_packetRecv.GetSize() - 4;m_nTotalBytes += nDataLen;m_nPackNum++;//m_logFile<<"CTFTPServer::ProcessRecvData() 接收数据大小为:"<<nDataLen<<std::endl;size_t nWrited = fwrite(dataBuf,1,nDataLen,m_fileRecv);//m_logFile<<"CTFTPServer::ProcessRecvData() 写入文件大小为:"<<nWrited<<std::endl;//发完了if (nDataLen < TFTP_DATA_PKT_SIZE){fclose(m_fileRecv);m_logFile<<"CTFTPServer::ProcessRecvData() 文件接收完毕,关闭文件……,接收大小为:"<<m_nTotalBytes<<std::endl;m_logFile<<"CTFTPServer::ProcessRecvData() 文件接收完毕,关闭文件……,接收数据块大小为:"<<m_nPackNum<<std::endl;}m_packetRecv.Clear();m_packetSend.MakeACK(dwDataNum);//发送数据int nLenSended = ::sendto(m_sockSvr,(char*)m_packetSend.GetData(),m_packetSend.GetSize(),0,(SOCKADDR *)&m_clientAddr,sizeof(m_clientAddr));m_packetSend.Clear();break;}case TFTP_OPCODE_ACK:{ATLTRACE("确认包/n");break;}case TFTP_OPCODE_ERROR:{ATLTRACE("/n");break;}default:{ATLTRACE("/n");break;}}}

只在本机测试了下，不知道在internet上面是啥效果。