Question

这是程序代码，它应该发送一个简单的'ping'。我知道我可以使用IcmpSendEcho2()函数，但我决定这样做：

struct ICMPh
{
unsigned char typ;
unsigned char kod;
unsigned short suma_spr;
unsigned short id;
unsigned short seq;
};
unsigned short CalcChecksum (char *pBuffer, int nLen)
 { 
  ////Checksum for ICMP is calculated in the same way as for IP header
  //This code was taken from: http://www.netfor2.com/ipsum.htm

  unsigned short nWord;
  unsigned int nSum = 0;
  int i;


  for (i = 0; i < nLen; i = i + 2)
  {
      nWord =((pBuffer [i] << 8)& 0xFF00) + (pBuffer [i + 1] & 0xFF);
      nSum = nSum + (unsigned int)nWord;  
  }


 while (nSum >> 16)
  {
      nSum = (nSum & 0xFFFF) + (nSum >> 16);
  }

  //One's complement the result
  nSum = ~nSum;

  return ((unsigned short) nSum);
 }
int _tmain(int argc, _TCHAR* argv[])
{
WSADATA wsaData;
if(WSAStartup(MAKEWORD(2,2),&wsaData)==SOCKET_ERROR)
{
    cout<<"ERROR at startup:\n";
    cout<<WSAGetLastError()<<"\n";
    system("pause");
    WSACleanup();
    return -1;
}
SOCKET soc;
int seq=0;

soc=socket(AF_INET,SOCK_RAW,IPPROTO_ICMP);
if(soc==INVALID_SOCKET)
{
    cout<<"ERROR: INVALID SOCKET\n";
    cout<<WSAGetLastError()<<"\n";
    system("pause");
    WSACleanup();
    return -1;
}
char* addres=new char;
cin>>addres;

SOCKADDR_IN adr;
adr.sin_addr.S_un.S_addr=inet_addr(addres);
adr.sin_family=AF_INET;
adr.sin_port=rand();

ICMPh icmp;
icmp.kod=0;
icmp.seq=htons(seq++);
icmp.typ=8;
icmp.suma_spr=0;
icmp.id=htons(rand());

int size=32;
char *buffer;

buffer=new char[sizeof(ICMPh)+size];
memcpy_s(buffer,sizeof(ICMPh),&icmp,sizeof(ICMPh));
memset(buffer+sizeof(ICMPh),'x',size);

icmp.suma_spr=htons(CalcChecksum(buffer,sizeof(ICMPh)+size));

memcpy_s(buffer,sizeof(ICMPh),&icmp,sizeof(ICMPh));

if(sendto(soc,buffer,sizeof(ICMPh)+size,0,(SOCKADDR*)&adr,sizeof(SOCKADDR_IN))==SOCKET_ERROR)
{
    cout<<"FAIL at 'sendto':\n";
    cout<<WSAGetLastError()<<"\n";
    system("pause");
    WSACleanup();
    delete []buffer;
    return -1;
}
else
    cout<<"FINE";
WSACleanup();
system("pause");
delete []buffer;
return 0;
}

这就是问题所在。一切都很好，直到sendto()功能。我收到10013错误代码表单WSAGetLastError()，表示WSAEACCES Permission denied
我启动这个应用程序管理员权限，所以我不知道为什么我不能使用此套接字配置发送数据。

Answer 1

对于sendto()，WSAEACCES与用户权限无关。如果您没有足够的权限使用RAW套接字，则会在socket()上出现错误。 Read the documentation。当sendto()报告WSAEACCES时，表示您的sockaddr_in结构未正确填写。我看到你的代码中有三个与此相关的错误：

1）在使用之前，您没有将sockaddr_in归零。这样做非常重要。

2）您正在分配1个字符的缓冲区以从用户接收目标地址。对于IPv4地址（包括空终止符），缓冲区需要为16个字符。所以你有一个缓冲区溢出。

3）分配htons()字段时，您没有致电sin_port。

Windows套接字错误10013

1 个答案: