c++ - Windows Socket 无法绑定(bind) VPN IP 地址

Question

我正在尝试绑定(bind)到 VPN 网络上的特定 IP，我能够 ping 它，连接它，也能够在特定端口上远程登录，但我的 Windows MFC 程序给出错误代码 10049，我无法进一步调试此问题的任何帮助将不胜感激，我在 Visual Studio 2012 Win 7 上运行它，远程客户端在 Linux 变体上运行。

这是我收到错误的代码的一部分，基本上 IP 地址是可配置的，但我正在对其进行硬编码以进行调试。

   CStarDoc          *p_doc = (CStarDoc*) lpparam; 
   BOOL              fFlag = TRUE;
   const int         MAX_MSGLEN = max(sizeof(DISP_INFO_T ), sizeof(REASON_STRING_T ));
   char              buffer[MAX_MSGLEN];
   DISP_INFO_T       *p_disp_info_buffer = (DISP_INFO_T *) buffer;
   DISP_INFO_T       disp_info_combined; //receiving combined butter
   DISP_INFO_T_1     *p_disp_info_buffer1; //receiving buffer pointer for DispInfo1
   DISP_INFO_T_2     *p_disp_info_buffer2; //receiving buffer pointer for DispInfo2
   int               msgReceived = 0; // Initially, is 0. 
   // For the same msgNumber, when the program receives the first portion of buffer, set to 1,
   // When the program receives both portions, set it to 0. 
   // When the program misses any portion for the same msgNumber, set to 0 also.
   int               currentMsgNum1 = 0;  
   int               currentMsgNum2 = 0;  
   int               err;
   CString           msg;
   SOCKADDR_IN       saUDPPortIn;
   SOCKADDR_IN       From;

   struct addrinfo *result = NULL;
   struct addrinfo *ptr = NULL;
   struct addrinfo hints;
   ::memset( &hints,0, sizeof(hints) );
   hints.ai_family = AF_UNSPEC;
   //hints.ai_socktype = SOCK_DGRAM;
   //hints.ai_protocol = IPPROTO_UDP;
   char asideip[] = "192.168.1.129";
   BOOL              OtherSideIsStandby = FALSE; 
   static BOOL       DoFirstMsg = TRUE; 

   //   p_disp_info_combined = & disp_info_combined;
   p_doc->ThreadRunning = TRUE;
   p_doc->udpsocket = socket(AF_INET, SOCK_DGRAM, 0);
   if (INVALID_SOCKET == p_doc->udpsocket)
   {
       CString msg =  "Invalid socket: "+ WSAGetLastError();
       AfxMessageBox(msg);
       return(-1);
   }

   long ip = 0;
   int sockbufsize = 0; 
   int timeout = 2000; 

   // This is the IP that matches the IP of the QNX machines in all but the last octet. 
   // Note: it is in host byte format. 
   int errcode = getaddrinfo(asideip,NULL,&hints,&result);
   for(ptr = result;ptr != NULL ;ptr=ptr->ai_next) 
   {
       switch (ptr->ai_family) 
       {
         default: break;
         case AF_INET :
           ip = p_doc->MyIP;
           saUDPPortIn.sin_family = AF_INET;
           saUDPPortIn.sin_addr.s_addr = (((SOCKADDR_IN*) ptr->ai_addr)->sin_addr).s_addr;
           saUDPPortIn.sin_port = htons(p_doc->port_addr );
           int length = sizeof(buffer) *2;
           //err = setsockopt(p_doc->udpsocket,SOL_SOCKET, SO_REUSEADDR, (char *)&fFlag, sizeof(fFlag));
           //err = setsockopt(p_doc->udpsocket,SOL_SOCKET, SO_BROADCAST, (char *)&fFlag, sizeof(fFlag));
           err = setsockopt(p_doc->udpsocket, SOL_SOCKET, SO_RCVBUF, (char *)&length, sizeof(length));

           // Keep from hanging forever. 
           err = setsockopt(p_doc->udpsocket, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
           err = bind(p_doc->udpsocket, (SOCKADDR FAR *)&saUDPPortIn, sizeof(SOCKADDR_IN));
           if (err == SOCKET_ERROR)
           {
             int errcode = WSAGetLastError();
             closesocket(p_doc->udpsocket); 
             /*    msg.Format("Network Connectivity failed, Please Check Network. "); 
             AfxMessageBox(msg);   
             closesocket(p_doc->udpsocket); 
         p_doc->udpsocket = -1;                                          // task is trying to attach to the port.   
             return(1);*/
           }
       }
   }

谢谢

Answer 1

您不能绑定(bind)到远程地址，如您的错误所示，就是这种情况。您使用具有本地 IP 和端口的绑定(bind)系统调用。

这是 MSDN 对您的错误的描述:

WSAEADDRNOTAVAIL 10049

Cannot assign requested address. The requested address is not valid in its context. This normally results from an attempt to bind to an address that is not valid for the local computer. This can also result from connect, sendto, WSAConnect, WSAJoinLeaf, or WSASendTo when the remote address or port is not valid for a remote computer (for example, address or port 0).