nfqws: do not reconstruct synack-split in syn mode (6d52b49b) · Commits · git-mirror / Zapret

nfq/desync.c

+31 −29

Original line number	Diff line number	Diff line
		@@ -1188,11 +1188,20 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint

		//ConntrackPoolDump(&params.conntrack);

		if (dp->wsize && tcp_synack_segment(dis->tcp))
		if (tcp_synack_segment(dis->tcp))
		{
		if (dp->wsize)
		{
		tcp_rewrite_winsize(dis->tcp, dp->wsize, dp->wscale);
		verdict=VERDICT_MODIFY;
		}
		if (dp->synack_split==SS_SYN)
		{
		DLOG("split SYNACK : clearing ACK bit\n");
		dis->tcp->th_flags &= ~TH_ACK;
		verdict=VERDICT_MODIFY;
		}
		}

		if (bReverse)
		{
		@@ -1280,20 +1289,14 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
		}
		}

		if (dp->synack_split!=SS_NONE && tcp_synack_segment(dis->tcp))
		if ((dp->synack_split==SS_SYNACK \|\| dp->synack_split==SS_ACKSYN) && tcp_synack_segment(dis->tcp))
		{
		// reconstruct required

		dis->tcp->th_flags &= ~TH_ACK;
		tcp_fix_checksum(dis->tcp,dis->transport_len, dis->ip, dis->ip6);

		char ss[2],i,ct;
		if (dp->synack_split==SS_SYN)
		{
		ct=1;
		ss[0] = 'S';
		}
		else
		{
		ct=2;
		char ss[2],i;
		if (dp->synack_split==SS_SYNACK)
		{
		ss[0] = 'S';
		@@ -1312,18 +1315,17 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
		DLOG_ERR("cannot prepare split SYNACK ACK part\n");
		goto send_orig;
		}
		}
		for (int i=0;i<ct;i++)
		for (int i=0;i<2;i++)
		{
		switch(ss[i])
		{
		case 'S':
		DLOG("sending split SYNACK : SYN\n");
		DLOG("split SYNACK : SYN\n");
		if (!rawsend_rep(dp->desync_repeats,(struct sockaddr *)&dst, desync_fwmark, ifout , dis->data_pkt, dis->len_pkt))
		goto send_orig;
		break;
		case 'A':
		DLOG("sending split SYNACK : ACK\n");
		DLOG("split SYNACK : ACK\n");
		if (!rawsend_rep(dp->desync_repeats,(struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
		goto send_orig;
		break;

nfq/nfqws.c

+1 −7

Original line number	Diff line number	Diff line
		@@ -527,13 +527,7 @@ static int win_main(const char *windivert_filter)
		WINDIVERT_ADDRESS wa;
		char ifname[IFNAMSIZ];

		if (params.daemon)
		{
		// cygwin loses current dir
		char *cwd = get_current_dir_name();
		daemonize();
		chdir(cwd);
		}
		if (params.daemon) daemonize();

		if (*params.pidfile && !writepid(params.pidfile))
		{

nfq/sec.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -343,9 +343,13 @@ void print_id(void)
		#endif



		void daemonize(void)
		{
		int pid;
		#ifdef __CYGWIN__
		char *cwd = get_current_dir_name();
		#endif

		pid = fork();
		if (pid == -1)
		@@ -356,6 +360,10 @@ void daemonize(void)
		else if (pid != 0)
		exit(0);

		#ifdef __CYGWIN__
		chdir(get_current_dir_name());
		#endif

		if (setsid() == -1)
		exit(2);
		if (chdir("/") == -1)