int doit(int argc, char* argv[])
{
// Check for correct command-line args
if (argc < 2) {
cerr << "usage: ping <host>" << endl;
return 1;
}
// Load the ICMP.DLL
HINSTANCE hIcmp = LoadLibrary("ICMP.DLL");
if (hIcmp == 0) {
cerr << "Unable to locate ICMP.DLL!" << endl;
return 2;
}
// Look up an IP address for the given host name
struct hostent* phe;
if ((phe = gethostbyname(argv[1])) == 0) {
cerr << "Could not find IP address for " << argv[1] << endl;
return 3;
}
// Get handles to the functions inside ICMP.DLL that we'll need
typedef HANDLE (WINAPI* pfnHV)(VOID);
typedef BOOL (WINAPI* pfnBH)(HANDLE);
typedef DWORD (WINAPI* pfnDHDPWPipPDD)(HANDLE, DWORD, LPVOID, WORD,
PIP_OPTION_INFORMATION, LPVOID, DWORD, DWORD); // evil, no?
pfnHV pIcmpCreateFile;
pfnBH pIcmpCloseHandle;
pfnDHDPWPipPDD pIcmpSendEcho;
pIcmpCreateFile = (pfnHV)GetProcAddress(hIcmp,
"IcmpCreateFile");
pIcmpCloseHandle = (pfnBH)GetProcAddress(hIcmp,
"IcmpCloseHandle");
pIcmpSendEcho = (pfnDHDPWPipPDD)GetProcAddress(hIcmp,
"IcmpSendEcho");
if ((pIcmpCreateFile == 0) || (pIcmpCloseHandle == 0) ||
(pIcmpSendEcho == 0)) {
cerr << "Failed to get proc addr for function." << endl;
return 4;
}
// Open the ping service
HANDLE hIP = pIcmpCreateFile();
if (hIP == INVALID_HANDLE_VALUE) {
cerr << "Unable to open ping service." << endl;
return 5;
}
int main(int argc, char* argv[])
{
WSAData wsaData;
if (WSAStartup(MAKEWORD(1, 1), &wsaData) != 0) {
return 255;
}
int retval = doit(argc, argv);
WSACleanup();
return retval;
}
icmpdefs.h
// Structures required to use functions in ICMP.DLL
typedef struct {
unsigned char Ttl; // Time To Live
unsigned char Tos; // Type Of Service
unsigned char Flags; // IP header flags
unsigned char OptionsSize; // Size in bytes of options data
unsigned char *OptionsData; // Pointer to options data
} IP_OPTION_INFORMATION, * PIP_OPTION_INFORMATION;
typedef struct {
DWORD Address; // Replying address
unsigned long Status; // Reply status
unsigned long RoundTripTime; // RTT in milliseconds
unsigned short DataSize; // Echo data size
unsigned short Reserved; // Reserved for system use
void *Data; // Pointer to the echo data
IP_OPTION_INFORMATION Options; // Reply options
} IP_ECHO_REPLY, * PIP_ECHO_REPLY;