/*
TCP port scanner
Written and Maintained by Michael Craze
TODO:
make it use threads..
make it check UDP
make it scan ip address ranges for public use
ip address ranges for private use:
Class Networks
A 10.0.0.0 through 10.255.255.255
B 172.16.0.0 through 172.31.0.0
C 192.168.0.0 through 192.168.255.0
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
typedef struct{
char *ip;
int sport;
int eport;
} Host;
void usage(char *a){
fprintf(stderr,"Invalid invocation of %s\n",a);
printf("Usage: %s \n",a);
exit(1);
}
/* Main programs starts*/
int main(int argc, char **argv){
int sd;
int port;
int rval;
int checkip;
int pcount = 0;
/* going to use these ints to iterate
through public IP classes to find all
open servers to automate attacks.
*/
/*
int A,B,C,D;
*/
/*
char *message="shell";
*/
/*
char response[1024];
*/
Host *h;
struct hostent *hostaddr;
struct sockaddr_in servaddr;
if (argc < 4 ){
usage(argv[0]);
}
h = (Host *)malloc(sizeof(Host));
if(h == NULL){
fprintf(stderr,"couldn't allocate memory for %s\n",argv[1]);
exit(1);
}
if(sscanf(argv[1],"%d",&checkip) != 1){
fprintf(stderr,"%s was not a valid ip address\n",argv[1]);
usage(argv[0]);
}
if(sscanf(argv[2],"%d",&h->sport) != 1){
fprintf(stderr,"%s was not a valid integer\n",argv[2]);
usage(argv[0]);
}
if(sscanf(argv[3],"%d",&h->eport) != 1){
fprintf(stderr,"%s was not a valid integer\n",argv[3]);
usage(argv[0]);
}
h->ip = strdup(argv[1]);
printf("Scanning host: %s on ports %d thru %d\n", h->ip,h->sport,h->eport);
/* Start scanning ports */
for (port = h->sport; port <= h->eport; port++){
/* creating the tcp socket */
sd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
if (sd == -1){
perror("Socket()\n");
return (errno);
}
memset( &servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(port);
hostaddr = gethostbyname(h->ip);
memcpy(&servaddr.sin_addr, hostaddr->h_addr, hostaddr->h_length);
/* below connects to the specified ip in hostaddr */
rval = connect(sd, (struct sockaddr *) &servaddr, sizeof(servaddr));
if(rval != -1){
printf(" %-7d %-10s\n",port,"is open");
pcount++;
}
close(sd);
}
if(pcount == 0){
printf("No ports in range %d-%d are open on host %s\n",h->sport,h->eport,h->ip);
}
else{
printf("%d ports in range %d-%d are open on host %s\n",pcount,h->sport,h->eport,h->ip);
}
free(h);
return 0;
}
