rdns.c

非常高效的扫描器

// this a program i wrote awhile ago and modified to only check if an ip
// is resolvable and if it is, print it . . . -jsbach

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>

int printhost(char *host);
void class_a(char *ip);
void class_b(char *ip);
void class_c(char *ip);

main(int argc, char  **argv) 
{
char ch;
if ( argc < 3 )
  {
    printf("usage: %s -abc ip_address
    example: %s -c 206.171.90
    or %s -b 206.171
    or %s -a 206\n", argv[0], argv[0], argv[0], argv[0]);
    exit(1);
  }

ch=getopt(argc,argv,"abc");
        switch(ch)
          {
          case 'a':
            {
            class_a(argv[2]);
            break;
            }
          case 'b':
           {
           class_b(argv[2]);
           break;
           }
          case 'c':
           {
           class_c(argv[2]);
          break;
     }
  }
}

int printhost(char *host)
{
	struct in_addr *ip;
	struct hostent *hp;

	if (inet_aton((char *)host, (struct in_addr *)&ip) == 0) 
	{
       	printf("invalid ip\n");
		exit(0);
	}

	/* // htonl(ip->s_addr); */

	hp = gethostbyaddr((char *)&ip, sizeof(struct in_addr),AF_INET);

	if (hp != NULL) 
	{
		printf("%s\n", host);
	}
}

void class_a(char *ip)
{


char a[3], b[3], ipstring[32];
int count,count1,count2, ca;
/* parse the ip address */

for (count=0; count < 5; count++)
  {
  if (ip[count] == '.') break;
  a[count]=ip[count];
  }
ca=atoi(a);

for(count=255; count > 0; count--)
  {
    for(count1=255; count1 > 0; count1--)
      {
	for(count2=255; count2 > 0; count2--)
	  {
	  sprintf(ipstring, "%d.%d.%d.%d",ca, count, count1, count2);
	  printhost(ipstring);
	  fflush(stdout);
	  }
      }
  }
}

void class_b(char *ip)
{

  /* PARSING THE IP AND PUTTING IT IN INT'S CA AND CB "!!!" */
char a[3], b[3], ipstring[32];
int count,count2, ca, cb;
/* parse the ip address */


for (count=0; count < 5; count++)
  {
  if (ip[count] == '.') break;
  a[count]=ip[count];
  }
ca=atoi(a);

count++;
for (count2=0; count < 8; count++)
  {
  if (ip[count] == '\0') break;
  b[count2]=ip[count];
  count2++;
  }
strcat(b, "\0");
cb=atoi(b);
/* WE ARE NOW DONE PARSING Z IP ADDRESS */
for(count=0; count < 255; count++)
  {
  for(count2=0; count2 < 255; count2++)
    {
      sprintf(ipstring, "%d.%d.%d.%d", ca, cb, count, count2);
      printhost(ipstring);
	fflush(stdout);
    }
  }

}

void class_c(char *ip)
{

char a[3], b[3], c[3], ipstring[32];
int count,count2, count3, ca, cb, cc;
/* parse the ip address */


for (count=0; count < 5; count++)
  {
  if (ip[count] == '.') break;
  a[count]=ip[count];
  }
ca=atoi(a);

count++;
for (count2=0; count < 8; count++)
  {
  if (ip[count] == '.') break;
  b[count2]=ip[count];
  count2++;
  }
count++;
for(count3=0; count < 15; count++)
  {
    if(ip[count] == '\0') break;
    c[count3]=ip[count];
    count3++;
  }
strcat(c, "\0");
cb=atoi(b);
cc=atoi(c);


for (count=255; count > 0; count--)
  {
    sprintf(ipstring, "%d.%d.%d.%d", ca, cb, cc, count);
    printhost(ipstring);
	fflush(stdout);
  }

}