zapret/nfq/darkmagic.c

1941 lines
52 KiB
C

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/param.h>
#include <errno.h>
#include <fcntl.h>
#ifndef IP_NODEFRAG
// for very old toolchains
#define IP_NODEFRAG 22
#endif
#include "darkmagic.h"
#include "helpers.h"
#include "params.h"
#include "nfqws.h"
#ifdef __CYGWIN__
#include <wlanapi.h>
#include <netlistmgr.h>
#endif
uint32_t net32_add(uint32_t netorder_value, uint32_t cpuorder_increment)
{
return htonl(ntohl(netorder_value) + cpuorder_increment);
}
uint32_t net16_add(uint16_t netorder_value, uint16_t cpuorder_increment)
{
return htons(ntohs(netorder_value) + cpuorder_increment);
}
uint8_t *tcp_find_option(struct tcphdr *tcp, uint8_t kind)
{
uint8_t *t = (uint8_t *)(tcp + 1);
uint8_t *end = (uint8_t *)tcp + (tcp->th_off << 2);
while (t < end)
{
switch (*t)
{
case 0: // end
return NULL;
case 1: // noop
t++;
break;
default: // kind,len,data
if ((t + 1) >= end || t[1] < 2 || (t + t[1]) > end)
return NULL;
if (*t == kind)
return t;
t += t[1];
break;
}
}
return NULL;
}
uint32_t *tcp_find_timestamps(struct tcphdr *tcp)
{
uint8_t *t = tcp_find_option(tcp, 8);
return (t && t[1] == 10) ? (uint32_t *)(t + 2) : NULL;
}
uint8_t tcp_find_scale_factor(const struct tcphdr *tcp)
{
uint8_t *scale = tcp_find_option((struct tcphdr *)tcp, 3); // tcp option 3 - scale factor
if (scale && scale[1] == 3)
return scale[2];
return SCALE_NONE;
}
bool tcp_has_fastopen(const struct tcphdr *tcp)
{
uint8_t *opt;
// new style RFC7413
opt = tcp_find_option((struct tcphdr *)tcp, 34);
if (opt)
return true;
// old style RFC6994
opt = tcp_find_option((struct tcphdr *)tcp, 254);
return opt && opt[1] >= 4 && opt[2] == 0xF9 && opt[3] == 0x89;
}
// n prefix (nsport, nwsize) means network byte order
static void fill_tcphdr(
struct tcphdr *tcp, uint32_t fooling, uint8_t tcp_flags,
uint32_t nseq, uint32_t nack_seq,
uint16_t nsport, uint16_t ndport,
uint16_t nwsize, uint8_t scale_factor,
uint32_t *timestamps,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
uint16_t data_len)
{
char *tcpopt = (char *)(tcp + 1);
uint8_t t = 0;
memset(tcp, 0, sizeof(*tcp));
tcp->th_sport = nsport;
tcp->th_dport = ndport;
if (fooling & FOOL_BADSEQ)
{
tcp->th_seq = net32_add(nseq, badseq_increment);
tcp->th_ack = net32_add(nack_seq, badseq_ack_increment);
}
else
{
tcp->th_seq = nseq;
tcp->th_ack = nack_seq;
}
tcp->th_off = 5;
if ((fooling & FOOL_DATANOACK) && !(tcp_flags & (TH_SYN | TH_RST)) && data_len)
tcp_flags &= ~TH_ACK;
*((uint8_t *)tcp + 13) = tcp_flags;
tcp->th_win = nwsize;
if (fooling & FOOL_MD5SIG)
{
tcpopt[0] = 19; // kind
tcpopt[1] = 18; // len
*(uint32_t *)(tcpopt + 2) = random();
*(uint32_t *)(tcpopt + 6) = random();
*(uint32_t *)(tcpopt + 10) = random();
*(uint32_t *)(tcpopt + 14) = random();
t = 18;
}
if (timestamps || (fooling & FOOL_TS))
{
tcpopt[t] = 8; // kind
tcpopt[t + 1] = 10; // len
// forge only TSecr if orig timestamp is present
*(uint32_t *)(tcpopt + t + 2) = timestamps ? timestamps[0] : -1;
*(uint32_t *)(tcpopt + t + 6) = (timestamps && !(fooling & FOOL_TS)) ? timestamps[1] : -1;
t += 10;
}
if (scale_factor != SCALE_NONE)
{
tcpopt[t++] = 3;
tcpopt[t++] = 3;
tcpopt[t++] = scale_factor;
}
while (t & 3)
tcpopt[t++] = 1; // noop
tcp->th_off += t >> 2;
tcp->th_sum = 0;
}
static uint16_t tcpopt_len(uint32_t fooling, const uint32_t *timestamps, uint8_t scale_factor)
{
uint16_t t = 0;
if (fooling & FOOL_MD5SIG)
t = 18;
if ((fooling & FOOL_TS) || timestamps)
t += 10;
if (scale_factor != SCALE_NONE)
t += 3;
return (t + 3) & ~3;
}
// n prefix (nsport, nwsize) means network byte order
static void fill_udphdr(struct udphdr *udp, uint16_t nsport, uint16_t ndport, uint16_t len_payload)
{
udp->uh_sport = nsport;
udp->uh_dport = ndport;
udp->uh_ulen = htons(len_payload + sizeof(struct udphdr));
udp->uh_sum = 0;
}
static void fill_iphdr(struct ip *ip, const struct in_addr *src, const struct in_addr *dst, uint16_t pktlen, uint8_t proto, uint8_t ttl)
{
ip->ip_tos = 0;
ip->ip_sum = 0;
ip->ip_off = 0;
ip->ip_v = 4;
ip->ip_hl = 5;
ip->ip_len = htons(pktlen);
ip->ip_id = 0;
ip->ip_ttl = ttl;
ip->ip_p = proto;
ip->ip_src = *src;
ip->ip_dst = *dst;
}
static void fill_ip6hdr(struct ip6_hdr *ip6, const struct in6_addr *src, const struct in6_addr *dst, uint16_t payloadlen, uint8_t proto, uint8_t ttl)
{
ip6->ip6_ctlun.ip6_un1.ip6_un1_flow = htonl(0x60000000);
ip6->ip6_ctlun.ip6_un1.ip6_un1_plen = htons(payloadlen);
ip6->ip6_ctlun.ip6_un1.ip6_un1_nxt = proto;
ip6->ip6_ctlun.ip6_un1.ip6_un1_hlim = ttl;
ip6->ip6_src = *src;
ip6->ip6_dst = *dst;
}
bool prepare_tcp_segment4(
const struct sockaddr_in *src, const struct sockaddr_in *dst,
uint8_t tcp_flags,
uint32_t nseq, uint32_t nack_seq,
uint16_t nwsize,
uint8_t scale_factor,
uint32_t *timestamps,
uint8_t ttl,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
const void *data, uint16_t len,
uint8_t *buf, size_t *buflen)
{
uint16_t tcpoptlen = tcpopt_len(fooling, timestamps, scale_factor);
uint16_t ip_payload_len = sizeof(struct tcphdr) + tcpoptlen + len;
uint16_t pktlen = sizeof(struct ip) + ip_payload_len;
if (pktlen > *buflen)
return false;
struct ip *ip = (struct ip *)buf;
struct tcphdr *tcp = (struct tcphdr *)(ip + 1);
uint8_t *payload = (uint8_t *)(tcp + 1) + tcpoptlen;
fill_iphdr(ip, &src->sin_addr, &dst->sin_addr, pktlen, IPPROTO_TCP, ttl);
fill_tcphdr(tcp, fooling, tcp_flags, nseq, nack_seq, src->sin_port, dst->sin_port, nwsize, scale_factor, timestamps, badseq_increment, badseq_ack_increment, len);
memcpy(payload, data, len);
tcp4_fix_checksum(tcp, ip_payload_len, &ip->ip_src, &ip->ip_dst);
if (fooling & FOOL_BADSUM)
tcp->th_sum ^= htons(0xBEAF);
*buflen = pktlen;
return true;
}
bool prepare_tcp_segment6(
const struct sockaddr_in6 *src, const struct sockaddr_in6 *dst,
uint8_t tcp_flags,
uint32_t nseq, uint32_t nack_seq,
uint16_t nwsize,
uint8_t scale_factor,
uint32_t *timestamps,
uint8_t ttl,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
const void *data, uint16_t len,
uint8_t *buf, size_t *buflen)
{
uint16_t tcpoptlen = tcpopt_len(fooling, timestamps, scale_factor);
uint16_t transport_payload_len = sizeof(struct tcphdr) + tcpoptlen + len;
uint16_t ip_payload_len = transport_payload_len +
8 * !!((fooling & (FOOL_HOPBYHOP | FOOL_HOPBYHOP2)) == FOOL_HOPBYHOP) +
16 * !!(fooling & FOOL_HOPBYHOP2) +
8 * !!(fooling & FOOL_DESTOPT) +
8 * !!(fooling & FOOL_IPFRAG1);
uint16_t pktlen = sizeof(struct ip6_hdr) + ip_payload_len;
if (pktlen > *buflen)
return false;
struct ip6_hdr *ip6 = (struct ip6_hdr *)buf;
struct tcphdr *tcp = (struct tcphdr *)(ip6 + 1);
uint8_t proto = IPPROTO_TCP, *nexttype = NULL;
if (fooling & (FOOL_HOPBYHOP | FOOL_HOPBYHOP2))
{
struct ip6_hbh *hbh = (struct ip6_hbh *)tcp;
tcp = (struct tcphdr *)((uint8_t *)tcp + 8);
memset(hbh, 0, 8);
// extra HOPBYHOP header. standard violation
if (fooling & FOOL_HOPBYHOP2)
{
hbh = (struct ip6_hbh *)tcp;
tcp = (struct tcphdr *)((uint8_t *)tcp + 8);
memset(hbh, 0, 8);
}
hbh->ip6h_nxt = IPPROTO_TCP;
nexttype = &hbh->ip6h_nxt;
proto = IPPROTO_HOPOPTS;
}
if (fooling & FOOL_DESTOPT)
{
struct ip6_dest *dest = (struct ip6_dest *)tcp;
tcp = (struct tcphdr *)((uint8_t *)tcp + 8);
memset(dest, 0, 8);
dest->ip6d_nxt = IPPROTO_TCP;
if (nexttype)
*nexttype = IPPROTO_DSTOPTS;
else
proto = IPPROTO_DSTOPTS;
nexttype = &dest->ip6d_nxt;
}
if (fooling & FOOL_IPFRAG1)
{
struct ip6_frag *frag = (struct ip6_frag *)tcp;
tcp = (struct tcphdr *)((uint8_t *)tcp + sizeof(struct ip6_frag));
frag->ip6f_nxt = IPPROTO_TCP;
frag->ip6f_ident = htonl(1 + random() % 0xFFFFFFFF);
frag->ip6f_reserved = 0;
frag->ip6f_offlg = 0;
if (nexttype)
*nexttype = IPPROTO_FRAGMENT;
else
proto = IPPROTO_FRAGMENT;
}
uint8_t *payload = (uint8_t *)(tcp + 1) + tcpoptlen;
fill_ip6hdr(ip6, &src->sin6_addr, &dst->sin6_addr, ip_payload_len, proto, ttl);
fill_tcphdr(tcp, fooling, tcp_flags, nseq, nack_seq, src->sin6_port, dst->sin6_port, nwsize, scale_factor, timestamps, badseq_increment, badseq_ack_increment, len);
memcpy(payload, data, len);
tcp6_fix_checksum(tcp, transport_payload_len, &ip6->ip6_src, &ip6->ip6_dst);
if (fooling & FOOL_BADSUM)
tcp->th_sum ^= htons(0xBEAF);
*buflen = pktlen;
return true;
}
bool prepare_tcp_segment(
const struct sockaddr *src, const struct sockaddr *dst,
uint8_t tcp_flags,
uint32_t nseq, uint32_t nack_seq,
uint16_t nwsize,
uint8_t scale_factor,
uint32_t *timestamps,
uint8_t ttl,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
const void *data, uint16_t len,
uint8_t *buf, size_t *buflen)
{
return (src->sa_family == AF_INET && dst->sa_family == AF_INET) ? prepare_tcp_segment4((struct sockaddr_in *)src, (struct sockaddr_in *)dst, tcp_flags, nseq, nack_seq, nwsize, scale_factor, timestamps, ttl, fooling, badseq_increment, badseq_ack_increment, data, len, buf, buflen) : (src->sa_family == AF_INET6 && dst->sa_family == AF_INET6) ? prepare_tcp_segment6((struct sockaddr_in6 *)src, (struct sockaddr_in6 *)dst, tcp_flags, nseq, nack_seq, nwsize, scale_factor, timestamps, ttl, fooling, badseq_increment, badseq_ack_increment, data, len, buf, buflen)
: false;
}
// padlen<0 means payload shrinking
bool prepare_udp_segment4(
const struct sockaddr_in *src, const struct sockaddr_in *dst,
uint8_t ttl,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,
const void *data, uint16_t len,
uint8_t *buf, size_t *buflen)
{
if ((len + padlen) <= 0)
padlen = -(int)len + 1; // do not allow payload to be less that 1 byte
if ((len + padlen) > 0xFFFF)
padlen = 0xFFFF - len; // do not allow payload size to exceed u16 range
if (padlen < 0)
{
len += padlen;
padlen = 0;
}
uint16_t datalen = (uint16_t)(len + padlen);
uint16_t ip_payload_len = sizeof(struct udphdr) + datalen;
uint16_t pktlen = sizeof(struct ip) + ip_payload_len;
if (pktlen > *buflen)
return false;
struct ip *ip = (struct ip *)buf;
struct udphdr *udp = (struct udphdr *)(ip + 1);
uint8_t *payload = (uint8_t *)(udp + 1);
fill_iphdr(ip, &src->sin_addr, &dst->sin_addr, pktlen, IPPROTO_UDP, ttl);
fill_udphdr(udp, src->sin_port, dst->sin_port, datalen);
memcpy(payload, data, len);
if (padding)
fill_pattern(payload + len, padlen, padding, padding_size);
else
memset(payload + len, 0, padlen);
udp4_fix_checksum(udp, ip_payload_len, &ip->ip_src, &ip->ip_dst);
if (fooling & FOOL_BADSUM)
udp->uh_sum ^= htons(0xBEAF);
*buflen = pktlen;
return true;
}
bool prepare_udp_segment6(
const struct sockaddr_in6 *src, const struct sockaddr_in6 *dst,
uint8_t ttl,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,
const void *data, uint16_t len,
uint8_t *buf, size_t *buflen)
{
if ((len + padlen) <= 0)
padlen = -(int)len + 1; // do not allow payload to be less that 1 byte
if ((len + padlen) > 0xFFFF)
padlen = 0xFFFF - len; // do not allow payload size to exceed u16 range
if (padlen < 0)
{
len += padlen;
padlen = 0;
}
uint16_t datalen = (uint16_t)(len + padlen);
uint16_t transport_payload_len = sizeof(struct udphdr) + datalen;
uint16_t ip_payload_len = transport_payload_len +
8 * !!((fooling & (FOOL_HOPBYHOP | FOOL_HOPBYHOP2)) == FOOL_HOPBYHOP) +
16 * !!(fooling & FOOL_HOPBYHOP2) +
8 * !!(fooling & FOOL_DESTOPT) +
8 * !!(fooling & FOOL_IPFRAG1);
uint16_t pktlen = sizeof(struct ip6_hdr) + ip_payload_len;
if (pktlen > *buflen)
return false;
struct ip6_hdr *ip6 = (struct ip6_hdr *)buf;
struct udphdr *udp = (struct udphdr *)(ip6 + 1);
uint8_t proto = IPPROTO_UDP, *nexttype = NULL;
if (fooling & (FOOL_HOPBYHOP | FOOL_HOPBYHOP2))
{
struct ip6_hbh *hbh = (struct ip6_hbh *)udp;
udp = (struct udphdr *)((uint8_t *)udp + 8);
memset(hbh, 0, 8);
// extra HOPBYHOP header. standard violation
if (fooling & FOOL_HOPBYHOP2)
{
hbh = (struct ip6_hbh *)udp;
udp = (struct udphdr *)((uint8_t *)udp + 8);
memset(hbh, 0, 8);
}
hbh->ip6h_nxt = IPPROTO_UDP;
nexttype = &hbh->ip6h_nxt;
proto = IPPROTO_HOPOPTS;
}
if (fooling & FOOL_DESTOPT)
{
struct ip6_dest *dest = (struct ip6_dest *)udp;
udp = (struct udphdr *)((uint8_t *)udp + 8);
memset(dest, 0, 8);
dest->ip6d_nxt = IPPROTO_UDP;
if (nexttype)
*nexttype = IPPROTO_DSTOPTS;
else
proto = IPPROTO_DSTOPTS;
nexttype = &dest->ip6d_nxt;
}
if (fooling & FOOL_IPFRAG1)
{
struct ip6_frag *frag = (struct ip6_frag *)udp;
udp = (struct udphdr *)((uint8_t *)udp + sizeof(struct ip6_frag));
frag->ip6f_nxt = IPPROTO_UDP;
frag->ip6f_ident = htonl(1 + random() % 0xFFFFFFFF);
frag->ip6f_reserved = 0;
frag->ip6f_offlg = 0;
if (nexttype)
*nexttype = IPPROTO_FRAGMENT;
else
proto = IPPROTO_FRAGMENT;
}
uint8_t *payload = (uint8_t *)(udp + 1);
fill_ip6hdr(ip6, &src->sin6_addr, &dst->sin6_addr, ip_payload_len, proto, ttl);
fill_udphdr(udp, src->sin6_port, dst->sin6_port, datalen);
memcpy(payload, data, len);
if (padding)
fill_pattern(payload + len, padlen, padding, padding_size);
else
memset(payload + len, 0, padlen);
udp6_fix_checksum(udp, transport_payload_len, &ip6->ip6_src, &ip6->ip6_dst);
if (fooling & FOOL_BADSUM)
udp->uh_sum ^= htons(0xBEAF);
*buflen = pktlen;
return true;
}
bool prepare_udp_segment(
const struct sockaddr *src, const struct sockaddr *dst,
uint8_t ttl,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,
const void *data, uint16_t len,
uint8_t *buf, size_t *buflen)
{
return (src->sa_family == AF_INET && dst->sa_family == AF_INET) ? prepare_udp_segment4((struct sockaddr_in *)src, (struct sockaddr_in *)dst, ttl, fooling, padding, padding_size, padlen, data, len, buf, buflen) : (src->sa_family == AF_INET6 && dst->sa_family == AF_INET6) ? prepare_udp_segment6((struct sockaddr_in6 *)src, (struct sockaddr_in6 *)dst, ttl, fooling, padding, padding_size, padlen, data, len, buf, buflen)
: false;
}
bool ip6_insert_simple_hdr(uint8_t type, uint8_t *data_pkt, size_t len_pkt, uint8_t *buf, size_t *buflen)
{
if ((len_pkt + 8) <= *buflen && len_pkt >= sizeof(struct ip6_hdr))
{
struct ip6_hdr *ip6 = (struct ip6_hdr *)buf;
struct ip6_ext *hdr = (struct ip6_ext *)(ip6 + 1);
*ip6 = *(struct ip6_hdr *)data_pkt;
memset(hdr, 0, 8);
memcpy((uint8_t *)hdr + 8, data_pkt + sizeof(struct ip6_hdr), len_pkt - sizeof(struct ip6_hdr));
hdr->ip6e_nxt = ip6->ip6_ctlun.ip6_un1.ip6_un1_nxt;
ip6->ip6_ctlun.ip6_un1.ip6_un1_nxt = type;
ip6->ip6_ctlun.ip6_un1.ip6_un1_plen = net16_add(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen, 8);
*buflen = len_pkt + 8;
return true;
}
return false;
}
// split ipv4 packet into 2 fragments at data payload position frag_pos
bool ip_frag4(
const uint8_t *pkt, size_t pkt_size,
size_t frag_pos, uint32_t ident,
uint8_t *pkt1, size_t *pkt1_size,
uint8_t *pkt2, size_t *pkt2_size)
{
uint16_t hdrlen, payload_len;
// frag_pos must be 8-byte aligned
if (frag_pos & 7 || pkt_size < sizeof(struct ip))
return false;
payload_len = htons(((struct ip *)pkt)->ip_len);
hdrlen = ((struct ip *)pkt)->ip_hl << 2;
if (payload_len > pkt_size || hdrlen > pkt_size || hdrlen > payload_len)
return false;
payload_len -= hdrlen;
if (frag_pos >= payload_len || *pkt1_size < (hdrlen + frag_pos) || *pkt2_size < (hdrlen + payload_len - frag_pos))
return false;
memcpy(pkt1, pkt, hdrlen + frag_pos);
((struct ip *)pkt1)->ip_off = htons(IP_MF);
((struct ip *)pkt1)->ip_len = htons(hdrlen + frag_pos);
if (ident != (uint32_t)-1)
((struct ip *)pkt1)->ip_id = (uint16_t)ident;
*pkt1_size = hdrlen + frag_pos;
ip4_fix_checksum((struct ip *)pkt1);
memcpy(pkt2, pkt, hdrlen);
memcpy(pkt2 + hdrlen, pkt + hdrlen + frag_pos, payload_len - frag_pos);
((struct ip *)pkt2)->ip_off = htons((uint16_t)frag_pos >> 3 & IP_OFFMASK);
((struct ip *)pkt2)->ip_len = htons(hdrlen + payload_len - frag_pos);
if (ident != (uint32_t)-1)
((struct ip *)pkt2)->ip_id = (uint16_t)ident;
*pkt2_size = hdrlen + payload_len - frag_pos;
ip4_fix_checksum((struct ip *)pkt2);
return true;
}
bool ip_frag6(
const uint8_t *pkt, size_t pkt_size,
size_t frag_pos, uint32_t ident,
uint8_t *pkt1, size_t *pkt1_size,
uint8_t *pkt2, size_t *pkt2_size)
{
size_t payload_len, unfragmentable;
uint8_t *last_header_type;
uint8_t proto;
struct ip6_frag *frag;
const uint8_t *payload;
if (frag_pos & 7 || pkt_size < sizeof(struct ip6_hdr))
return false;
payload_len = sizeof(struct ip6_hdr) + htons(((struct ip6_hdr *)pkt)->ip6_ctlun.ip6_un1.ip6_un1_plen);
if (pkt_size < payload_len)
return false;
payload = pkt;
proto_skip_ipv6((uint8_t **)&payload, &payload_len, &proto, &last_header_type);
unfragmentable = payload - pkt;
// printf("pkt_size=%zu FRAG_POS=%zu payload_len=%zu unfragmentable=%zu dh=%zu\n",pkt_size,frag_pos,payload_len,unfragmentable,last_header_type - pkt);
if (frag_pos >= payload_len ||
*pkt1_size < (unfragmentable + sizeof(struct ip6_frag) + frag_pos) ||
*pkt2_size < (unfragmentable + sizeof(struct ip6_frag) + payload_len - frag_pos))
{
return false;
}
memcpy(pkt1, pkt, unfragmentable);
((struct ip6_hdr *)pkt1)->ip6_ctlun.ip6_un1.ip6_un1_plen = htons(unfragmentable - sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + frag_pos);
pkt1[last_header_type - pkt] = IPPROTO_FRAGMENT;
frag = (struct ip6_frag *)(pkt1 + unfragmentable);
frag->ip6f_nxt = proto;
frag->ip6f_reserved = 0;
frag->ip6f_offlg = IP6F_MORE_FRAG;
frag->ip6f_ident = ident;
memcpy(frag + 1, pkt + unfragmentable, frag_pos);
*pkt1_size = unfragmentable + sizeof(struct ip6_frag) + frag_pos;
memcpy(pkt2, pkt, sizeof(struct ip6_hdr));
((struct ip6_hdr *)pkt2)->ip6_ctlun.ip6_un1.ip6_un1_plen = htons(unfragmentable - sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + payload_len - frag_pos);
pkt2[last_header_type - pkt] = IPPROTO_FRAGMENT;
frag = (struct ip6_frag *)(pkt2 + unfragmentable);
frag->ip6f_nxt = proto;
frag->ip6f_reserved = 0;
frag->ip6f_offlg = htons(frag_pos);
frag->ip6f_ident = ident;
memcpy(frag + 1, pkt + unfragmentable + frag_pos, payload_len - frag_pos);
*pkt2_size = unfragmentable + sizeof(struct ip6_frag) + payload_len - frag_pos;
return true;
}
bool ip_frag(
const uint8_t *pkt, size_t pkt_size,
size_t frag_pos, uint32_t ident,
uint8_t *pkt1, size_t *pkt1_size,
uint8_t *pkt2, size_t *pkt2_size)
{
if (proto_check_ipv4(pkt, pkt_size))
return ip_frag4(pkt, pkt_size, frag_pos, ident, pkt1, pkt1_size, pkt2, pkt2_size);
else if (proto_check_ipv6(pkt, pkt_size))
return ip_frag6(pkt, pkt_size, frag_pos, ident, pkt1, pkt1_size, pkt2, pkt2_size);
else
return false;
}
void rewrite_ttl(struct ip *ip, struct ip6_hdr *ip6, uint8_t ttl)
{
if (ip)
ip->ip_ttl = ttl;
if (ip6)
ip6->ip6_ctlun.ip6_un1.ip6_un1_hlim = ttl;
}
void extract_ports(const struct tcphdr *tcphdr, const struct udphdr *udphdr, uint8_t *proto, uint16_t *sport, uint16_t *dport)
{
if (sport)
*sport = htons(tcphdr ? tcphdr->th_sport : udphdr ? udphdr->uh_sport
: 0);
if (dport)
*dport = htons(tcphdr ? tcphdr->th_dport : udphdr ? udphdr->uh_dport
: 0);
if (proto)
*proto = tcphdr ? IPPROTO_TCP : udphdr ? IPPROTO_UDP
: -1;
}
void extract_endpoints(const struct ip *ip, const struct ip6_hdr *ip6hdr, const struct tcphdr *tcphdr, const struct udphdr *udphdr, struct sockaddr_storage *src, struct sockaddr_storage *dst)
{
if (ip)
{
struct sockaddr_in *si;
if (dst)
{
si = (struct sockaddr_in *)dst;
si->sin_family = AF_INET;
si->sin_port = tcphdr ? tcphdr->th_dport : udphdr ? udphdr->uh_dport
: 0;
si->sin_addr = ip->ip_dst;
}
if (src)
{
si = (struct sockaddr_in *)src;
si->sin_family = AF_INET;
si->sin_port = tcphdr ? tcphdr->th_sport : udphdr ? udphdr->uh_sport
: 0;
si->sin_addr = ip->ip_src;
}
}
else if (ip6hdr)
{
struct sockaddr_in6 *si;
if (dst)
{
si = (struct sockaddr_in6 *)dst;
si->sin6_family = AF_INET6;
si->sin6_port = tcphdr ? tcphdr->th_dport : udphdr ? udphdr->uh_dport
: 0;
si->sin6_addr = ip6hdr->ip6_dst;
si->sin6_flowinfo = 0;
si->sin6_scope_id = 0;
}
if (src)
{
si = (struct sockaddr_in6 *)src;
si->sin6_family = AF_INET6;
si->sin6_port = tcphdr ? tcphdr->th_sport : udphdr ? udphdr->uh_sport
: 0;
si->sin6_addr = ip6hdr->ip6_src;
si->sin6_flowinfo = 0;
si->sin6_scope_id = 0;
}
}
}
const char *proto_name(uint8_t proto)
{
switch (proto)
{
case IPPROTO_TCP:
return "tcp";
case IPPROTO_UDP:
return "udp";
case IPPROTO_ICMP:
return "icmp";
case IPPROTO_ICMPV6:
return "icmp6";
case IPPROTO_IGMP:
return "igmp";
case IPPROTO_ESP:
return "esp";
case IPPROTO_AH:
return "ah";
case IPPROTO_IPV6:
return "6in4";
case IPPROTO_IPIP:
return "4in4";
#ifdef IPPROTO_GRE
case IPPROTO_GRE:
return "gre";
#endif
#ifdef IPPROTO_SCTP
case IPPROTO_SCTP:
return "sctp";
#endif
default:
return NULL;
}
}
static void str_proto_name(char *s, size_t s_len, uint8_t proto)
{
const char *name = proto_name(proto);
if (name)
snprintf(s, s_len, "%s", name);
else
snprintf(s, s_len, "%u", proto);
}
uint16_t family_from_proto(uint8_t l3proto)
{
switch (l3proto)
{
case IPPROTO_IP:
return AF_INET;
case IPPROTO_IPV6:
return AF_INET6;
default:
return -1;
}
}
static void str_srcdst_ip(char *s, size_t s_len, const void *saddr, const void *daddr)
{
char s_ip[16], d_ip[16];
*s_ip = *d_ip = 0;
inet_ntop(AF_INET, saddr, s_ip, sizeof(s_ip));
inet_ntop(AF_INET, daddr, d_ip, sizeof(d_ip));
snprintf(s, s_len, "%s => %s", s_ip, d_ip);
}
void str_ip(char *s, size_t s_len, const struct ip *ip)
{
char ss[35], s_proto[16];
str_srcdst_ip(ss, sizeof(ss), &ip->ip_src, &ip->ip_dst);
str_proto_name(s_proto, sizeof(s_proto), ip->ip_p);
snprintf(s, s_len, "%s proto=%s ttl=%u", ss, s_proto, ip->ip_ttl);
}
void print_ip(const struct ip *ip)
{
char s[66];
str_ip(s, sizeof(s), ip);
printf("%s", s);
}
void str_srcdst_ip6(char *s, size_t s_len, const void *saddr, const void *daddr)
{
char s_ip[40], d_ip[40];
*s_ip = *d_ip = 0;
inet_ntop(AF_INET6, saddr, s_ip, sizeof(s_ip));
inet_ntop(AF_INET6, daddr, d_ip, sizeof(d_ip));
snprintf(s, s_len, "%s => %s", s_ip, d_ip);
}
void str_ip6hdr(char *s, size_t s_len, const struct ip6_hdr *ip6hdr, uint8_t proto)
{
char ss[83], s_proto[16];
str_srcdst_ip6(ss, sizeof(ss), &ip6hdr->ip6_src, &ip6hdr->ip6_dst);
str_proto_name(s_proto, sizeof(s_proto), proto);
snprintf(s, s_len, "%s proto=%s ttl=%u", ss, s_proto, ip6hdr->ip6_hlim);
}
void print_ip6hdr(const struct ip6_hdr *ip6hdr, uint8_t proto)
{
char s[128];
str_ip6hdr(s, sizeof(s), ip6hdr, proto);
printf("%s", s);
}
void str_tcphdr(char *s, size_t s_len, const struct tcphdr *tcphdr)
{
char flags[7], *f = flags;
if (tcphdr->th_flags & TH_SYN)
*f++ = 'S';
if (tcphdr->th_flags & TH_ACK)
*f++ = 'A';
if (tcphdr->th_flags & TH_RST)
*f++ = 'R';
if (tcphdr->th_flags & TH_FIN)
*f++ = 'F';
if (tcphdr->th_flags & TH_PUSH)
*f++ = 'P';
if (tcphdr->th_flags & TH_URG)
*f++ = 'U';
*f = 0;
snprintf(s, s_len, "sport=%u dport=%u flags=%s seq=%u ack_seq=%u", htons(tcphdr->th_sport), htons(tcphdr->th_dport), flags, htonl(tcphdr->th_seq), htonl(tcphdr->th_ack));
}
void print_tcphdr(const struct tcphdr *tcphdr)
{
char s[80];
str_tcphdr(s, sizeof(s), tcphdr);
printf("%s", s);
}
void str_udphdr(char *s, size_t s_len, const struct udphdr *udphdr)
{
snprintf(s, s_len, "sport=%u dport=%u", htons(udphdr->uh_sport), htons(udphdr->uh_dport));
}
void print_udphdr(const struct udphdr *udphdr)
{
char s[30];
str_udphdr(s, sizeof(s), udphdr);
printf("%s", s);
}
bool proto_check_ipv4(const uint8_t *data, size_t len)
{
return len >= 20 && (data[0] & 0xF0) == 0x40 &&
len >= ((data[0] & 0x0F) << 2);
}
// move to transport protocol
void proto_skip_ipv4(uint8_t **data, size_t *len)
{
size_t l;
l = (**data & 0x0F) << 2;
*data += l;
*len -= l;
}
bool proto_check_tcp(const uint8_t *data, size_t len)
{
return len >= 20 && len >= ((data[12] & 0xF0) >> 2);
}
void proto_skip_tcp(uint8_t **data, size_t *len)
{
size_t l;
l = ((*data)[12] & 0xF0) >> 2;
*data += l;
*len -= l;
}
bool proto_check_udp(const uint8_t *data, size_t len)
{
return len >= 8 && len >= (data[4] << 8 | data[5]);
}
void proto_skip_udp(uint8_t **data, size_t *len)
{
*data += 8;
*len -= 8;
}
bool proto_check_ipv6(const uint8_t *data, size_t len)
{
return len >= 40 && (data[0] & 0xF0) == 0x60 &&
(len - 40) >= htons(*(uint16_t *)(data + 4)); // payload length
}
// move to transport protocol
// proto_type = 0 => error
void proto_skip_ipv6(uint8_t **data, size_t *len, uint8_t *proto_type, uint8_t **last_header_type)
{
size_t hdrlen;
uint8_t HeaderType;
if (proto_type)
*proto_type = 0; // put error in advance
HeaderType = (*data)[6]; // NextHeader field
if (last_header_type)
*last_header_type = (*data) + 6;
*data += 40;
*len -= 40; // skip IPv6 base header
while (*len > 0) // need at least one byte for NextHeader field
{
switch (HeaderType)
{
case 0: // Hop-by-Hop Options
case 43: // routing
case 51: // authentication
case 60: // Destination Options
case 135: // mobility
case 139: // Host Identity Protocol Version v2
case 140: // Shim6
if (*len < 2)
return; // error
hdrlen = 8 + ((*data)[1] << 3);
break;
case 44: // fragment. length fixed to 8, hdrlen field defined as reserved
hdrlen = 8;
break;
case 59: // no next header
return; // error
default:
// we found some meaningful payload. it can be TCP, UDP, ICMP or some another exotic shit
if (proto_type)
*proto_type = HeaderType;
return;
}
if (*len < hdrlen)
return; // error
HeaderType = **data;
if (last_header_type)
*last_header_type = *data;
// advance to the next header location
*len -= hdrlen;
*data += hdrlen;
}
// we have garbage
}
void proto_dissect_l3l4(
uint8_t *data, size_t len,
struct ip **ip, struct ip6_hdr **ip6,
uint8_t *proto,
struct tcphdr **tcp,
struct udphdr **udp,
size_t *transport_len,
uint8_t **data_payload, size_t *len_payload)
{
*ip = NULL;
*ip6 = NULL;
*proto = 0;
*tcp = NULL;
*transport_len = 0;
*udp = NULL;
*data_payload = NULL;
*len_payload = 0;
if (proto_check_ipv4(data, len))
{
*ip = (struct ip *)data;
*proto = (*ip)->ip_p;
proto_skip_ipv4(&data, &len);
}
else if (proto_check_ipv6(data, len))
{
*ip6 = (struct ip6_hdr *)data;
proto_skip_ipv6(&data, &len, proto, NULL);
}
else
{
return;
}
if (*proto == IPPROTO_TCP && proto_check_tcp(data, len))
{
*tcp = (struct tcphdr *)data;
*transport_len = len;
proto_skip_tcp(&data, &len);
*data_payload = data;
*len_payload = len;
}
else if (*proto == IPPROTO_UDP && proto_check_udp(data, len))
{
*udp = (struct udphdr *)data;
*transport_len = len;
proto_skip_udp(&data, &len);
*data_payload = data;
*len_payload = len;
}
}
bool tcp_synack_segment(const struct tcphdr *tcphdr)
{
/* check for set bits in TCP hdr */
return ((tcphdr->th_flags & (TH_URG | TH_ACK | TH_PUSH | TH_RST | TH_SYN | TH_FIN)) == (TH_ACK | TH_SYN));
}
bool tcp_syn_segment(const struct tcphdr *tcphdr)
{
/* check for set bits in TCP hdr */
return ((tcphdr->th_flags & (TH_URG | TH_ACK | TH_PUSH | TH_RST | TH_SYN | TH_FIN)) == TH_SYN);
}
bool tcp_ack_segment(const struct tcphdr *tcphdr)
{
/* check for set bits in TCP hdr */
return ((tcphdr->th_flags & (TH_URG | TH_ACK | TH_PUSH | TH_RST | TH_SYN | TH_FIN)) == TH_ACK);
}
void tcp_rewrite_wscale(struct tcphdr *tcp, uint8_t scale_factor)
{
uint8_t *scale, scale_factor_old;
if (scale_factor != SCALE_NONE)
{
scale = tcp_find_option(tcp, 3); // tcp option 3 - scale factor
if (scale && scale[1] == 3) // length should be 3
{
scale_factor_old = scale[2];
// do not allow increasing scale factor
if (scale_factor >= scale_factor_old)
DLOG("Scale factor %u unchanged\n", scale_factor_old);
else
{
scale[2] = scale_factor;
DLOG("Scale factor change %u => %u\n", scale_factor_old, scale_factor);
}
}
}
}
// scale_factor=SCALE_NONE - do not change
void tcp_rewrite_winsize(struct tcphdr *tcp, uint16_t winsize, uint8_t scale_factor)
{
uint16_t winsize_old;
winsize_old = htons(tcp->th_win); // << scale_factor;
tcp->th_win = htons(winsize);
DLOG("Window size change %u => %u\n", winsize_old, winsize);
tcp_rewrite_wscale(tcp, scale_factor);
}
#ifdef __CYGWIN__
static HANDLE w_filter = NULL;
static OVERLAPPED ovl = {.hEvent = NULL};
static const struct str_list_head *wlan_filter_ssid = NULL, *nlm_filter_net = NULL;
static DWORD logical_net_filter_tick = 0;
uint32_t w_win32_error = 0;
INetworkListManager *pNetworkListManager = NULL;
static void guid2str(const GUID *guid, char *str)
{
snprintf(str, 37, "%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X", guid->Data1, guid->Data2, guid->Data3, guid->Data4[0], guid->Data4[1], guid->Data4[2], guid->Data4[3], guid->Data4[4], guid->Data4[5], guid->Data4[6], guid->Data4[7]);
}
static bool str2guid(const char *str, GUID *guid)
{
unsigned int u[11], k;
if (36 != strlen(str) || 11 != sscanf(str, "%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X", u + 0, u + 1, u + 2, u + 3, u + 4, u + 5, u + 6, u + 7, u + 8, u + 9, u + 10))
return false;
guid->Data1 = u[0];
if ((u[1] & 0xFFFF0000) || (u[2] & 0xFFFF0000))
return false;
guid->Data2 = (USHORT)u[1];
guid->Data3 = (USHORT)u[2];
for (k = 0; k < 8; k++)
{
if (u[k + 3] & 0xFFFFFF00)
return false;
guid->Data4[k] = (UCHAR)u[k + 3];
}
return true;
}
static const char *sNetworkCards = "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\NetworkCards";
// get adapter name from guid string
static bool AdapterID2Name(const GUID *guid, char *name, DWORD name_len)
{
char sguid[39], sidx[32], val[256];
HKEY hkNetworkCards, hkCard;
DWORD dwIndex, dwLen;
bool bRet = false;
WCHAR namew[128];
DWORD namew_len;
if (name_len < 2)
return false;
if ((w_win32_error = RegOpenKeyExA(HKEY_LOCAL_MACHINE, sNetworkCards, 0, KEY_ENUMERATE_SUB_KEYS, &hkNetworkCards)) == ERROR_SUCCESS)
{
guid2str(guid, sguid + 1);
sguid[0] = '{';
sguid[37] = '}';
sguid[38] = '\0';
for (dwIndex = 0;; dwIndex++)
{
dwLen = sizeof(sidx) - 1;
w_win32_error = RegEnumKeyExA(hkNetworkCards, dwIndex, sidx, &dwLen, NULL, NULL, NULL, NULL);
if (w_win32_error == ERROR_SUCCESS)
{
sidx[dwLen] = '\0';
if ((w_win32_error = RegOpenKeyExA(hkNetworkCards, sidx, 0, KEY_QUERY_VALUE, &hkCard)) == ERROR_SUCCESS)
{
dwLen = sizeof(val) - 1;
if ((w_win32_error = RegQueryValueExA(hkCard, "ServiceName", NULL, NULL, val, &dwLen)) == ERROR_SUCCESS)
{
val[dwLen] = '\0';
if (!strcmp(val, sguid))
{
namew_len = sizeof(namew) - sizeof(WCHAR);
if ((w_win32_error = RegQueryValueExW(hkCard, L"Description", NULL, NULL, (LPBYTE)namew, &namew_len)) == ERROR_SUCCESS)
{
namew[namew_len / sizeof(WCHAR)] = L'\0';
if (WideCharToMultiByte(CP_UTF8, 0, namew, -1, name, name_len, NULL, NULL))
bRet = true;
}
}
}
RegCloseKey(hkCard);
}
if (bRet)
break;
}
else
break;
}
RegCloseKey(hkNetworkCards);
}
return bRet;
}
bool win_dark_init(const struct str_list_head *ssid_filter, const struct str_list_head *nlm_filter)
{
win_dark_deinit();
if (LIST_EMPTY(ssid_filter))
ssid_filter = NULL;
if (LIST_EMPTY(nlm_filter))
nlm_filter = NULL;
if (nlm_filter)
{
if (SUCCEEDED(w_win32_error = CoInitialize(NULL)))
{
if (FAILED(w_win32_error = CoCreateInstance(&CLSID_NetworkListManager, NULL, CLSCTX_ALL, &IID_INetworkListManager, (LPVOID *)&pNetworkListManager)))
{
CoUninitialize();
return false;
}
}
else
return false;
}
nlm_filter_net = nlm_filter;
wlan_filter_ssid = ssid_filter;
return true;
}
bool win_dark_deinit(void)
{
if (pNetworkListManager)
{
pNetworkListManager->lpVtbl->Release(pNetworkListManager);
pNetworkListManager = NULL;
}
if (nlm_filter_net)
CoUninitialize();
wlan_filter_ssid = nlm_filter_net = NULL;
}
bool nlm_list(bool bAll)
{
bool bRet = true;
if (SUCCEEDED(w_win32_error = CoInitialize(NULL)))
{
INetworkListManager *pNetworkListManager;
if (SUCCEEDED(w_win32_error = CoCreateInstance(&CLSID_NetworkListManager, NULL, CLSCTX_ALL, &IID_INetworkListManager, (LPVOID *)&pNetworkListManager)))
{
IEnumNetworks *pEnumNetworks;
if (SUCCEEDED(w_win32_error = pNetworkListManager->lpVtbl->GetNetworks(pNetworkListManager, NLM_ENUM_NETWORK_ALL, &pEnumNetworks)))
{
INetwork *pNet;
INetworkConnection *pConn;
IEnumNetworkConnections *pEnumConnections;
VARIANT_BOOL bIsConnected, bIsConnectedInet;
NLM_NETWORK_CATEGORY category;
GUID idNet, idAdapter;
BSTR bstrName;
char Name[128], Name2[128];
int connected;
for (connected = 1; connected >= !bAll; connected--)
{
for (;;)
{
if (FAILED(w_win32_error = pEnumNetworks->lpVtbl->Next(pEnumNetworks, 1, &pNet, NULL)))
{
bRet = false;
break;
}
if (w_win32_error != S_OK)
break;
if (SUCCEEDED(w_win32_error = pNet->lpVtbl->get_IsConnected(pNet, &bIsConnected)) &&
SUCCEEDED(w_win32_error = pNet->lpVtbl->get_IsConnectedToInternet(pNet, &bIsConnectedInet)) &&
SUCCEEDED(w_win32_error = pNet->lpVtbl->GetNetworkId(pNet, &idNet)) &&
SUCCEEDED(w_win32_error = pNet->lpVtbl->GetCategory(pNet, &category)) &&
SUCCEEDED(w_win32_error = pNet->lpVtbl->GetName(pNet, &bstrName)))
{
if (!!bIsConnected == connected)
{
if (WideCharToMultiByte(CP_UTF8, 0, bstrName, -1, Name, sizeof(Name), NULL, NULL))
{
printf("Name : %s", Name);
if (bIsConnected)
printf(" (connected)");
if (bIsConnectedInet)
printf(" (inet)");
printf(" (%s)\n",
category == NLM_NETWORK_CATEGORY_PUBLIC ? "public" : category == NLM_NETWORK_CATEGORY_PRIVATE ? "private"
: category == NLM_NETWORK_CATEGORY_DOMAIN_AUTHENTICATED ? "domain"
: "unknown");
guid2str(&idNet, Name);
printf("NetID : %s\n", Name);
if (connected && SUCCEEDED(w_win32_error = pNet->lpVtbl->GetNetworkConnections(pNet, &pEnumConnections)))
{
while ((w_win32_error = pEnumConnections->lpVtbl->Next(pEnumConnections, 1, &pConn, NULL)) == S_OK)
{
if (SUCCEEDED(w_win32_error = pConn->lpVtbl->GetAdapterId(pConn, &idAdapter)))
{
guid2str(&idAdapter, Name);
if (AdapterID2Name(&idAdapter, Name2, sizeof(Name2)))
printf("Adapter : %s (%s)\n", Name2, Name);
else
printf("Adapter : %s\n", Name);
}
pConn->lpVtbl->Release(pConn);
}
pEnumConnections->lpVtbl->Release(pEnumConnections);
}
printf("\n");
}
else
{
w_win32_error = HRESULT_FROM_WIN32(GetLastError());
bRet = false;
}
}
SysFreeString(bstrName);
}
else
bRet = false;
pNet->lpVtbl->Release(pNet);
if (!bRet)
break;
}
if (!bRet)
break;
pEnumNetworks->lpVtbl->Reset(pEnumNetworks);
}
pEnumNetworks->lpVtbl->Release(pEnumNetworks);
}
else
bRet = false;
pNetworkListManager->lpVtbl->Release(pNetworkListManager);
}
else
bRet = false;
}
else
bRet = false;
CoUninitialize();
return bRet;
}
static bool nlm_filter_match(const struct str_list_head *nlm_list)
{
// no filter given. always matches.
if (!nlm_list || LIST_EMPTY(nlm_list))
{
w_win32_error = 0;
return true;
}
bool bRet = true, bMatch = false;
IEnumNetworks *pEnum;
if (SUCCEEDED(w_win32_error = pNetworkListManager->lpVtbl->GetNetworks(pNetworkListManager, NLM_ENUM_NETWORK_CONNECTED, &pEnum)))
{
INetwork *pNet;
GUID idNet, g;
BSTR bstrName;
char Name[128];
struct str_list *nlm;
for (;;)
{
if (FAILED(w_win32_error = pEnum->lpVtbl->Next(pEnum, 1, &pNet, NULL)))
{
bRet = false;
break;
}
if (w_win32_error != S_OK)
break;
if (SUCCEEDED(w_win32_error = pNet->lpVtbl->GetNetworkId(pNet, &idNet)) &&
SUCCEEDED(w_win32_error = pNet->lpVtbl->GetName(pNet, &bstrName)))
{
if (WideCharToMultiByte(CP_UTF8, 0, bstrName, -1, Name, sizeof(Name), NULL, NULL))
{
LIST_FOREACH(nlm, nlm_list, next)
{
bMatch = !strcmp(Name, nlm->str) || str2guid(nlm->str, &g) && !memcmp(&idNet, &g, sizeof(GUID));
if (bMatch)
break;
}
}
else
{
w_win32_error = HRESULT_FROM_WIN32(GetLastError());
bRet = false;
}
SysFreeString(bstrName);
}
else
bRet = false;
pNet->lpVtbl->Release(pNet);
if (!bRet || bMatch)
break;
}
pEnum->lpVtbl->Release(pEnum);
}
else
bRet = false;
return bRet && bMatch;
}
static bool wlan_filter_match(const struct str_list_head *ssid_list)
{
DWORD dwCurVersion;
HANDLE hClient = NULL;
PWLAN_INTERFACE_INFO_LIST pIfList = NULL;
PWLAN_INTERFACE_INFO pIfInfo;
PWLAN_CONNECTION_ATTRIBUTES pConnectInfo;
DWORD connectInfoSize, k;
bool bRes;
struct str_list *ssid;
size_t len;
// no filter given. always matches.
if (!ssid_list || LIST_EMPTY(ssid_list))
{
w_win32_error = 0;
return true;
}
w_win32_error = WlanOpenHandle(2, NULL, &dwCurVersion, &hClient);
if (w_win32_error != ERROR_SUCCESS)
goto fail;
w_win32_error = WlanEnumInterfaces(hClient, NULL, &pIfList);
if (w_win32_error != ERROR_SUCCESS)
goto fail;
for (k = 0; k < pIfList->dwNumberOfItems; k++)
{
pIfInfo = pIfList->InterfaceInfo + k;
if (pIfInfo->isState == wlan_interface_state_connected)
{
w_win32_error = WlanQueryInterface(hClient,
&pIfInfo->InterfaceGuid,
wlan_intf_opcode_current_connection,
NULL,
&connectInfoSize,
(PVOID *)&pConnectInfo,
NULL);
if (w_win32_error != ERROR_SUCCESS)
goto fail;
// printf("%s\n", pConnectInfo->wlanAssociationAttributes.dot11Ssid.ucSSID);
LIST_FOREACH(ssid, ssid_list, next)
{
len = strlen(ssid->str);
if (len == pConnectInfo->wlanAssociationAttributes.dot11Ssid.uSSIDLength && !memcmp(ssid->str, pConnectInfo->wlanAssociationAttributes.dot11Ssid.ucSSID, len))
{
WlanFreeMemory(pConnectInfo);
goto found;
}
}
WlanFreeMemory(pConnectInfo);
}
}
w_win32_error = 0;
fail:
bRes = false;
ex:
if (pIfList)
WlanFreeMemory(pIfList);
if (hClient)
WlanCloseHandle(hClient, 0);
return bRes;
found:
w_win32_error = 0;
bRes = true;
goto ex;
}
bool logical_net_filter_match(void)
{
return wlan_filter_match(wlan_filter_ssid) && nlm_filter_match(nlm_filter_net);
}
static bool logical_net_filter_match_rate_limited(void)
{
DWORD dwTick = GetTickCount() / 1000;
if (logical_net_filter_tick == dwTick)
return true;
logical_net_filter_tick = dwTick;
return logical_net_filter_match();
}
static HANDLE windivert_init_filter(const char *filter, UINT64 flags)
{
LPSTR errormessage = NULL;
HANDLE h, hMutex;
const char *mutex_name = "Global\\winws_windivert_mutex";
// windivert driver start in windivert.dll has race conditions
hMutex = CreateMutexA(NULL, TRUE, mutex_name);
if (hMutex && GetLastError() == ERROR_ALREADY_EXISTS)
WaitForSingleObject(hMutex, INFINITE);
h = WinDivertOpen(filter, WINDIVERT_LAYER_NETWORK, 0, flags);
w_win32_error = GetLastError();
if (hMutex)
{
ReleaseMutex(hMutex);
CloseHandle(hMutex);
SetLastError(w_win32_error);
}
if (h != INVALID_HANDLE_VALUE)
return h;
FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, w_win32_error, MAKELANGID(LANG_ENGLISH, SUBLANG_DEFAULT), (LPSTR)&errormessage, 0, NULL);
DLOG_ERR("windivert: error opening filter: %s", errormessage);
LocalFree(errormessage);
if (w_win32_error == ERROR_INVALID_IMAGE_HASH)
DLOG_ERR("windivert: try to disable secure boot and install OS patches\n");
return NULL;
}
void rawsend_cleanup(void)
{
if (w_filter)
{
CancelIoEx(w_filter, &ovl);
WinDivertClose(w_filter);
w_filter = NULL;
}
if (ovl.hEvent)
{
CloseHandle(ovl.hEvent);
ovl.hEvent = NULL;
}
}
bool windivert_init(const char *filter)
{
rawsend_cleanup();
w_filter = windivert_init_filter(filter, 0);
if (w_filter)
{
ovl.hEvent = CreateEventW(NULL, FALSE, FALSE, NULL);
if (!ovl.hEvent)
{
w_win32_error = GetLastError();
rawsend_cleanup();
return false;
}
return true;
}
return false;
}
static bool windivert_recv_filter(HANDLE hFilter, uint8_t *packet, size_t *len, WINDIVERT_ADDRESS *wa)
{
UINT recv_len;
DWORD err;
DWORD rd;
char c;
if (bQuit)
{
errno = EINTR;
return false;
}
if (!logical_net_filter_match_rate_limited())
{
errno = ENODEV;
return false;
}
usleep(0);
if (WinDivertRecvEx(hFilter, packet, *len, &recv_len, 0, wa, NULL, &ovl))
{
*len = recv_len;
return true;
}
for (;;)
{
w_win32_error = GetLastError();
switch (w_win32_error)
{
case ERROR_IO_PENDING:
// make signals working
while (WaitForSingleObject(ovl.hEvent, 50) == WAIT_TIMEOUT)
{
if (bQuit)
{
errno = EINTR;
return false;
}
if (!logical_net_filter_match_rate_limited())
{
errno = ENODEV;
return false;
}
usleep(0);
}
if (!GetOverlappedResult(hFilter, &ovl, &rd, TRUE))
continue;
*len = rd;
return true;
case ERROR_INSUFFICIENT_BUFFER:
errno = ENOBUFS;
break;
case ERROR_NO_DATA:
errno = ESHUTDOWN;
break;
default:
errno = EIO;
}
break;
}
return false;
}
bool windivert_recv(uint8_t *packet, size_t *len, WINDIVERT_ADDRESS *wa)
{
return windivert_recv_filter(w_filter, packet, len, wa);
}
static bool windivert_send_filter(HANDLE hFilter, const uint8_t *packet, size_t len, const WINDIVERT_ADDRESS *wa)
{
bool b = WinDivertSend(hFilter, packet, (UINT)len, NULL, wa);
w_win32_error = GetLastError();
return b;
}
bool windivert_send(const uint8_t *packet, size_t len, const WINDIVERT_ADDRESS *wa)
{
return windivert_send_filter(w_filter, packet, len, wa);
}
bool rawsend(const struct sockaddr *dst, uint32_t fwmark, const char *ifout, const void *data, size_t len)
{
WINDIVERT_ADDRESS wa;
memset(&wa, 0, sizeof(wa));
// pseudo interface id IfIdx.SubIfIdx
if (sscanf(ifout, "%u.%u", &wa.Network.IfIdx, &wa.Network.SubIfIdx) != 2)
{
errno = EINVAL;
return false;
}
wa.Outbound = 1;
wa.IPChecksum = 1;
wa.TCPChecksum = 1;
wa.UDPChecksum = 1;
wa.IPv6 = (dst->sa_family == AF_INET6);
return windivert_send(data, len, &wa);
}
#else // *nix
static int rawsend_sock4 = -1, rawsend_sock6 = -1;
static bool b_bind_fix4 = false, b_bind_fix6 = false;
static void rawsend_clean_sock(int *sock)
{
if (sock && *sock != -1)
{
close(*sock);
*sock = -1;
}
}
void rawsend_cleanup(void)
{
rawsend_clean_sock(&rawsend_sock4);
rawsend_clean_sock(&rawsend_sock6);
}
static int *rawsend_family_sock(sa_family_t family)
{
switch (family)
{
case AF_INET:
return &rawsend_sock4;
case AF_INET6:
return &rawsend_sock6;
default:
return NULL;
}
}
#ifdef BSD
int socket_divert(sa_family_t family)
{
int fd;
#ifdef __FreeBSD__
// freebsd14+ way
// don't want to use ifdefs with os version to make binaries compatible with all versions
fd = socket(PF_DIVERT, SOCK_RAW, 0);
if (fd == -1 && (errno == EPROTONOSUPPORT || errno == EAFNOSUPPORT || errno == EPFNOSUPPORT))
#endif
// freebsd13- or openbsd way
fd = socket(family, SOCK_RAW, IPPROTO_DIVERT);
return fd;
}
static int rawsend_socket_divert(sa_family_t family)
{
// HACK HACK HACK HACK HACK HACK HACK HACK
// FreeBSD doesnt allow IP_HDRINCL for IPV6
// OpenBSD doesnt allow rawsending tcp frames
// we either have to go to the link layer (its hard, possible problems arise, compat testing, ...) or use some HACKING
// from my point of view disabling direct ability to send ip frames is not security. its SHIT
int fd = socket_divert(family);
if (fd != -1 && !set_socket_buffers(fd, 4096, RAW_SNDBUF))
{
close(fd);
return -1;
}
return fd;
}
static int rawsend_sendto_divert(sa_family_t family, int sock, const void *buf, size_t len)
{
struct sockaddr_storage sa;
socklen_t slen;
#ifdef __FreeBSD__
// since FreeBSD 14 it requires hardcoded ipv4 values, although can also send ipv6 frames
family = AF_INET;
slen = sizeof(struct sockaddr_in);
#else
// OpenBSD requires correct family and size
switch (family)
{
case AF_INET:
slen = sizeof(struct sockaddr_in);
break;
case AF_INET6:
slen = sizeof(struct sockaddr_in6);
break;
default:
return -1;
}
#endif
memset(&sa, 0, slen);
sa.ss_family = family;
return sendto(sock, buf, len, 0, (struct sockaddr *)&sa, slen);
}
#endif
static int rawsend_socket_raw(int domain, int proto)
{
int fd = socket(domain, SOCK_RAW, proto);
if (fd != -1)
{
#ifdef __linux__
int s = RAW_SNDBUF / 2;
int r = 2048;
#else
int s = RAW_SNDBUF;
int r = 4096;
#endif
if (!set_socket_buffers(fd, r, s))
{
close(fd);
return -1;
}
}
return fd;
}
static bool set_socket_fwmark(int sock, uint32_t fwmark)
{
#ifdef BSD
#ifdef SO_USER_COOKIE
if (setsockopt(sock, SOL_SOCKET, SO_USER_COOKIE, &fwmark, sizeof(fwmark)) == -1)
{
DLOG_PERROR("rawsend: setsockopt(SO_USER_COOKIE)");
return false;
}
#endif
#elif defined(__linux__)
if (setsockopt(sock, SOL_SOCKET, SO_MARK, &fwmark, sizeof(fwmark)) == -1)
{
DLOG_PERROR("rawsend: setsockopt(SO_MARK)");
return false;
}
#endif
return true;
}
static int rawsend_socket(sa_family_t family)
{
int *sock = rawsend_family_sock(family);
if (!sock)
return -1;
if (*sock == -1)
{
int yes = 1, pri = 6;
// printf("rawsend_socket: family %d",family);
#ifdef __FreeBSD__
// IPPROTO_RAW with ipv6 in FreeBSD always returns EACCES on sendto.
// must use IPPROTO_TCP for ipv6. IPPROTO_RAW works for ipv4
// divert sockets are always v4 but accept both v4 and v6
*sock = rawsend_socket_divert(AF_INET);
#elif defined(__OpenBSD__) || defined(__APPLE__)
// OpenBSD does not allow sending TCP frames through raw sockets
// I dont know about macos. They have dropped ipfw in recent versions and their PF does not support divert-packet
*sock = rawsend_socket_divert(family);
#else
*sock = rawsend_socket_raw(family, IPPROTO_RAW);
#endif
if (*sock == -1)
{
DLOG_PERROR("rawsend: socket()");
return -1;
}
#ifdef __linux__
if (setsockopt(*sock, SOL_SOCKET, SO_PRIORITY, &pri, sizeof(pri)) == -1)
{
DLOG_PERROR("rawsend: setsockopt(SO_PRIORITY)");
goto exiterr;
}
if (family == AF_INET && setsockopt(*sock, IPPROTO_IP, IP_NODEFRAG, &yes, sizeof(yes)) == -1)
{
DLOG_PERROR("rawsend: setsockopt(IP_NODEFRAG)");
goto exiterr;
}
if (family == AF_INET && setsockopt(*sock, IPPROTO_IP, IP_FREEBIND, &yes, sizeof(yes)) == -1)
{
DLOG_PERROR("rawsend: setsockopt(IP_FREEBIND)");
goto exiterr;
}
if (family == AF_INET6 && setsockopt(*sock, SOL_IPV6, IPV6_FREEBIND, &yes, sizeof(yes)) == -1)
{
// DLOG_PERROR("rawsend: setsockopt(IPV6_FREEBIND)");
// don't error because it's supported only from kernel 4.15
}
#endif
}
return *sock;
exiterr:
rawsend_clean_sock(sock);
return -1;
}
bool rawsend_preinit(bool bind_fix4, bool bind_fix6)
{
b_bind_fix4 = bind_fix4;
b_bind_fix6 = bind_fix6;
// allow IPv6 disabled systems
return rawsend_socket(AF_INET) != -1 && (rawsend_socket(AF_INET6) != -1 || errno == EAFNOSUPPORT);
}
bool rawsend(const struct sockaddr *dst, uint32_t fwmark, const char *ifout, const void *data, size_t len)
{
ssize_t bytes;
int sock = rawsend_socket(dst->sa_family);
if (sock == -1)
return false;
if (!set_socket_fwmark(sock, fwmark))
return false;
int salen = dst->sa_family == AF_INET ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6);
struct sockaddr_storage dst2;
memcpy(&dst2, dst, salen);
if (dst->sa_family == AF_INET6)
((struct sockaddr_in6 *)&dst2)->sin6_port = 0; // or will be EINVAL in Linux
#if defined(BSD)
bytes = rawsend_sendto_divert(dst->sa_family, sock, data, len);
if (bytes == -1)
{
DLOG_PERROR("rawsend: sendto_divert");
return false;
}
return true;
#else
#ifdef __linux__
struct sockaddr_storage sa_src;
switch (dst->sa_family)
{
case AF_INET:
if (!b_bind_fix4)
goto nofix;
extract_endpoints(data, NULL, NULL, NULL, &sa_src, NULL);
break;
case AF_INET6:
if (!b_bind_fix6)
goto nofix;
extract_endpoints(NULL, data, NULL, NULL, &sa_src, NULL);
break;
default:
return false; // should not happen
}
// printf("family %u dev %s bind : ", dst->sa_family, ifout); print_sockaddr((struct sockaddr *)&sa_src); printf("\n");
if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifout, ifout ? strlen(ifout) + 1 : 0) == -1)
{
DLOG_PERROR("rawsend: setsockopt(SO_BINDTODEVICE)");
return false;
}
if (bind(sock, (const struct sockaddr *)&sa_src, dst->sa_family == AF_INET ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6)))
{
DLOG_PERROR("rawsend: bind (ignoring)");
// do not fail. this can happen regardless of IP_FREEBIND
// rebind to any address
memset(&sa_src, 0, sizeof(sa_src));
sa_src.ss_family = dst->sa_family;
if (bind(sock, (const struct sockaddr *)&sa_src, dst->sa_family == AF_INET ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6)))
{
DLOG_PERROR("rawsend: bind to any");
return false;
}
}
nofix:
#endif
// normal raw socket sendto
bytes = sendto(sock, data, len, 0, (struct sockaddr *)&dst2, salen);
if (bytes == -1)
{
DLOG_PERROR("rawsend: sendto");
return false;
}
return true;
#endif
}
#endif // not CYGWIN
bool rawsend_rp(const struct rawpacket *rp)
{
return rawsend((struct sockaddr *)&rp->dst, rp->fwmark, rp->ifout, rp->packet, rp->len);
}
bool rawsend_queue(struct rawpacket_tailhead *q)
{
struct rawpacket *rp;
bool b;
for (b = true; (rp = rawpacket_dequeue(q)); rawpacket_free(rp))
b &= rawsend_rp(rp);
return b;
}
// return guessed fake ttl value. 0 means unsuccessfull, should not perform autottl fooling
// ttl = TTL of incoming packet
uint8_t autottl_guess(uint8_t ttl, const autottl *attl)
{
uint8_t orig, path, fake;
// 18.65.168.125 ( cloudfront ) 255
// 157.254.246.178 128
// 1.1.1.1 64
// guess original ttl. consider path lengths less than 32 hops
if (ttl > 223)
orig = 255;
else if (ttl < 128 && ttl > 96)
orig = 128;
else if (ttl < 64 && ttl > 32)
orig = 64;
else
return 0;
path = orig - ttl;
fake = path > attl->delta ? path - attl->delta : attl->min;
if (fake < attl->min)
fake = attl->min;
else if (fake > attl->max)
fake = attl->max;
if (fake >= path)
return 0;
return fake;
}
void do_nat(bool bOutbound, struct ip *ip, struct ip6_hdr *ip6, struct tcphdr *tcphdr, struct udphdr *udphdr, const struct sockaddr_in *target4, const struct sockaddr_in6 *target6)
{
uint16_t nport;
if (ip && target4)
{
nport = target4->sin_port;
if (bOutbound)
ip->ip_dst = target4->sin_addr;
else
ip->ip_src = target4->sin_addr;
ip4_fix_checksum(ip);
}
else if (ip6 && target6)
{
nport = target6->sin6_port;
if (bOutbound)
ip6->ip6_dst = target6->sin6_addr;
else
ip6->ip6_src = target6->sin6_addr;
}
else
return;
if (nport)
{
if (tcphdr)
{
if (bOutbound)
tcphdr->th_dport = nport;
else
tcphdr->th_sport = nport;
}
if (udphdr)
{
if (bOutbound)
udphdr->uh_dport = nport;
else
udphdr->uh_sport = nport;
}
}
}
void verdict_tcp_csum_fix(uint8_t verdict, struct tcphdr *tcphdr, size_t transport_len, struct ip *ip, struct ip6_hdr *ip6hdr)
{
if (!(verdict & VERDICT_NOCSUM))
{
// always fix csum for windivert. original can be partial or bad
#ifndef __CYGWIN__
#ifdef __FreeBSD__
// FreeBSD tend to pass IPv6 frames with wrong checksum
if ((verdict & VERDICT_MASK) == VERDICT_MODIFY || ip6hdr)
#else
// if original packet was tampered earlier it needs checksum fixed
if ((verdict & VERDICT_MASK) == VERDICT_MODIFY)
#endif
#endif
tcp_fix_checksum(tcphdr, transport_len, ip, ip6hdr);
}
}
void verdict_udp_csum_fix(uint8_t verdict, struct udphdr *udphdr, size_t transport_len, struct ip *ip, struct ip6_hdr *ip6hdr)
{
if (!(verdict & VERDICT_NOCSUM))
{
// always fix csum for windivert. original can be partial or bad
#ifndef __CYGWIN__
#ifdef __FreeBSD__
// FreeBSD tend to pass IPv6 frames with wrong checksum
if ((verdict & VERDICT_MASK) == VERDICT_MODIFY || ip6hdr)
#else
// if original packet was tampered earlier it needs checksum fixed
if ((verdict & VERDICT_MASK) == VERDICT_MODIFY)
#endif
#endif
udp_fix_checksum(udphdr, transport_len, ip, ip6hdr);
}
}