Commit 706dd7b2 authored by bol-van's avatar bol-van
Browse files

nfqws: hostfakesplit send second fake

parent b2468a90

nfq/desync.c

+29 −11
Original line number Diff line number Diff line
@@ -835,7 +835,7 @@ static bool ipcache_get_hostname(const struct in_addr *a4, const struct in6_addr 
}





#ifdef BSD

#if defined(BSD)

// BSD pass to divert socket ip_id=0 and does not auto set it if sent via divert socket

static uint16_t IP4_IP_ID_FIX(const struct ip *ip)

{
@@ -2003,6 +2003,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint 
				// if 3 split pos : host, endhost, midhost

				if (multisplit_count>=2)

				{

					uint16_t ip_id_fake = (uint16_t)random();

					uint8_t *seg;

					size_t seg_len, host_size, pos_host, pos_endhost, pos_split_host, sz;

					char *fakehost;
@@ -2040,37 +2041,43 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint 
					if (host_size>=7) fakehost[host_size-4] = '.';

					DLOG("generated fake host: %s\n",fakehost);



					pkt1_len = sizeof(pkt1);

					pkt2_len = sizeof(pkt2);

					if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, false, 0,

							net32_add(dis->tcp->th_seq,pos_host), dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,

							DF,ttl_fake,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),

							DF,ttl_fake,IP4_TOS(dis->ip),ip_id_fake,IP6_FLOW(dis->ip6),

							dp->desync_fooling_mode,dp->desync_ts_increment,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,

							fakehost, host_size, pkt1, &pkt1_len))

							fakehost, host_size, pkt2, &pkt2_len))

					{

						free(fakehost);

						goto send_orig;

					}

					ip_id=IP4_IP_ID_NEXT(ip_id);

					DLOG("sending hostfakesplit fake host %zu-%zu len=%zu : ",pos_host,pos_endhost-1,host_size);

					hexdump_limited_dlog(fakehost,host_size,PKTDATA_MAXDUMP); DLOG("\n");

					if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt2, pkt2_len))

					{

						free(fakehost);

					if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))

						goto send_orig;

					}



					sz = pos_split_host ? pos_split_host-pos_host : host_size;

					pkt1_len = sizeof(pkt1);

					if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, false, 0,

								net32_add(dis->tcp->th_seq,pos_host), dis->tcp->th_ack,

								dis->tcp->th_win, scale_factor, timestamps,

								DF,ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),

								DF,ttl_orig,IP4_TOS(dis->ip),ip_id_fake,IP6_FLOW(dis->ip6),

								fooling_orig,0,0,0,

								seg+pos_host, sz, pkt1, &pkt1_len))

					{

						free(fakehost);

						goto send_orig;

					ip_id=IP4_IP_ID_NEXT(ip_id);

					}

					DLOG("sending hostfakesplit real host %s%zu-%zu len=%zu : ",pos_split_host ? "part 1 " : "",pos_host,pos_host+sz-1,sz);

					hexdump_limited_dlog(seg+pos_host,sz,PKTDATA_MAXDUMP); DLOG("\n");

					if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))

					{

						free(fakehost);

						goto send_orig;

					}



					if (pos_split_host)

					{
@@ -2079,16 +2086,27 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint 
						if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, false, 0,

									net32_add(dis->tcp->th_seq,pos_split_host), dis->tcp->th_ack,

									dis->tcp->th_win, scale_factor, timestamps,

									DF,ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),

									DF,ttl_orig,IP4_TOS(dis->ip),net16_add(ip_id_fake,1),IP6_FLOW(dis->ip6),

									fooling_orig,0,0,0,

									seg+pos_split_host, sz, pkt1, &pkt1_len))

						{

							free(fakehost);

							goto send_orig;

						ip_id=IP4_IP_ID_NEXT(ip_id);

						}

						DLOG("sending hostfakesplit real host part 2 %zu-%zu len=%zu : ",pos_split_host,pos_endhost-1,sz);

						hexdump_limited_dlog(seg+pos_split_host,sz,PKTDATA_MAXDUMP); DLOG("\n");

						if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))

						{

							free(fakehost);

							goto send_orig;

						}

					}



					DLOG("sending hostfakesplit fake(2) host %zu-%zu len=%zu : ",pos_host,pos_endhost-1,host_size);

					free(fakehost);

					hexdump_limited_dlog(fakehost,host_size,PKTDATA_MAXDUMP); DLOG("\n");

					if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt2, pkt2_len))

						goto send_orig;

						

					pkt1_len = sizeof(pkt1);

					if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, false, 0,