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这是程序的代码，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。一切正常，直到它sendto()发挥作用。我收到一个 10013 错误代码表单WSAGetLastError()，这意味着WSAEACCES Permission denied
我以管理员权限启动了这个应用程序，所以我不知道为什么我不能使用这个套接字配置发送数据。

4

1 回答 1

3

对于sendto(),WSAEACCES与用户权限无关。socket()如果您没有足够的权限来使用 RAW 套接字， 则会收到错误消息。阅读文档。当sendto()报告时WSAEACCES，这意味着您的sockaddr_in结构没有正确填写。我在您的代码中看到三个与此相关的错误：

1）您没有sockaddr_in在使用它之前将其归零。这样做很重要。

2) 您正在分配一个 1 字符的缓冲区来接收来自用户的目标地址。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。

htons()3）分配sin_port字段时您没有调用。

于 2012-06-11T00:19:03.840 回答