[ViewVC] Diff of: cvs/gvpe/src/vpn

Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.9 by pcg, Fri Mar 4 04:52:38 2005 UTC vs.
Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC

…		…
43		43
44	#include "netcompat.h"	44	#include "netcompat.h"
45		45
46	#include "vpn.h"	46	#include "vpn.h"
47		47
48	#define MIN_RETRY 1.	48	#define MIN_POLL_INTERVAL .02 // how often to poll minimally when the server has data
49	#define MAX_RETRY 6.	49	#define MAX_POLL_INTERVAL 6. // how often to poll minimally when the server has no data
		50	#define ACTIVITY_INTERVAL 5.
50		51
		52	#define INITIAL_TIMEOUT 0.1 // retry timeouts
		53	#define INITIAL_SYN_TIMEOUT 10. // retry timeout for initial syn
		54
		55	#define MIN_SEND_INTERVAL 0.01 // wait at least this time between sending requests
		56	#define MAX_SEND_INTERVAL 0.5 // optimistic?
		57
51	#define MAX_OUTSTANDING 400 // max. outstanding requests	58	#define MAX_OUTSTANDING 10 // max. outstanding requests
52	#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING	59	#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING, and backlog
53	#define MAX_RATE 100 // requests/s
54	#define MAX_BACKLOG (10*1024) // size of protocol backlog, must be > MAXSIZE	60	#define MAX_BACKLOG (100*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE
55		61
56	#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well	62	#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well
57	// 240 leaves about 4 bytes of server reply data	63	// 240 leaves about 4 bytes of server reply data
58	// every two request byte sless give room for one reply byte	64	// every two request bytes less give room for one reply byte
59		65
60	#define SEQNO_MASK 0xffff	66	#define SEQNO_MASK 0x3fff
61	#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )	67	#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )
62		68
63	#define MAX_LBL_SIZE 63	69	#define MAX_LBL_SIZE 63
64	#define MAX_PKT_SIZE 512	70	#define MAX_PKT_SIZE 512
65		71
		72	#define RR_TYPE_A 1
		73	#define RR_TYPE_NULL 10
66	#define RR_TYPE_TXT 16	74	#define RR_TYPE_TXT 16
67	#define RR_TYPE_ANY 255	75	#define RR_TYPE_ANY 255
		76
68	#define RR_CLASS_IN 1	77	#define RR_CLASS_IN 1
		78
		79	#define CMD_IP_1 207
		80	#define CMD_IP_2 46
		81	#define CMD_IP_3 236
		82	#define CMD_IP_RST 29
		83	#define CMD_IP_SYN 113
		84	#define CMD_IP_REJ 32
69		85
70	// works for cmaps up to 255 (not 256!)	86	// works for cmaps up to 255 (not 256!)
71	struct charmap	87	struct charmap
72	{	88	{
73	enum { INVALID = (u8)255 };	89	enum { INVALID = (u8)255 };
…		…
153	return dec_len [len];	169	return dec_len [len];
154	}	170	}
155		171
156	unsigned int basecoder::encode (char dst, u8 src, unsigned int len)	172	unsigned int basecoder::encode (char dst, u8 src, unsigned int len)
157	{	173	{
158	if (!len)	174	if (!len \|\| len > MAX_DEC_LEN)
159	return 0;	175	return 0;
160		176
161	int elen = encode_len (len);	177	int elen = encode_len (len);
162		178
163	mp_limb_t m [MAX_LIMBS];	179	mp_limb_t m [MAX_LIMBS];
…		…
182	return elen;	198	return elen;
183	}	199	}
184		200
185	unsigned int basecoder::decode (u8 dst, char src, unsigned int len)	201	unsigned int basecoder::decode (u8 dst, char src, unsigned int len)
186	{	202	{
187	if (!len)	203	if (!len \|\| len > MAX_ENC_LEN)
188	return 0;	204	return 0;
189		205
190	u8 src_ [MAX_ENC_LEN];	206	u8 src_ [MAX_ENC_LEN];
191	unsigned int elen = 0;	207	unsigned int elen = 0;
192		208
…		…
239	}	255	}
240	abort ();	256	abort ();
241	}	257	}
242	#endif	258	#endif
243		259
244	// the following sequence has been crafted to	260	//static basecoder cdc64 ("_dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI-");
245	// a) look somewhat random
246	// b) the even (and odd) indices never share the same character as upper/lowercase
247	// the "_" is not valid but widely accepted (all octets should be supported, but let's be conservative)
248	// the other sequences are obviously derived
249	//static basecoder cdc63 ("_dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI");	261	//static basecoder cdc63 ("_dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI");
250	static basecoder cdc62 ("dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI");	262	static basecoder cdc62 ("dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI");
251	//static basecoder cdc36 ("dphzr06qmjkb34tsvl81xaef92wgyo57ucni"); // unused as of yet	263	//static basecoder cdc36 ("dphzr06qmjkb34tsvl81xaef92wgyo57ucni"); // unused as of yet
252	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");	264	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");
253		265
254	/////////////////////////////////////////////////////////////////////////////	266	/////////////////////////////////////////////////////////////////////////////
255		267
256	#define HDRSIZE 6	268	#define HDRSIZE 6
257		269
258	inline void encode_header (char *data, int clientid, int seqno)	270	inline void encode_header (char *data, int clientid, int seqno, int retry = 0)
259	{	271	{
260	u8 hdr[3] = { clientid, seqno >> 8, seqno };	272	seqno &= SEQNO_MASK;
		273
		274	u8 hdr[3] = {
		275	clientid,
		276	(seqno >> 8) \| (retry << 6),
		277	seqno,
		278	};
261		279
262	assert (clientid < 256);	280	assert (clientid < 256);
263		281
264	cdc26.encode (data, hdr, 3);	282	cdc26.encode (data, hdr, 3);
265	}	283	}
…		…
269	u8 hdr[3];	287	u8 hdr[3];
270		288
271	cdc26.decode (hdr, data, HDRSIZE);	289	cdc26.decode (hdr, data, HDRSIZE);
272		290
273	clientid = hdr[0];	291	clientid = hdr[0];
274	seqno = (hdr[1] << 8) \| hdr[2];	292	seqno = ((hdr[1] << 8) \| hdr[2]) & SEQNO_MASK;
275	}	293	}
276		294
277	/////////////////////////////////////////////////////////////////////////////	295	/////////////////////////////////////////////////////////////////////////////
278		296
279	struct byte_stream	297	struct byte_stream
…		…
308	}	326	}
309		327
310	void byte_stream::remove (int count)	328	void byte_stream::remove (int count)
311	{	329	{
312	if (count > fill)	330	if (count > fill)
313	abort ();	331	assert (count <= fill);
314		332
315	memmove (data, data + count, fill -= count);	333	memmove (data, data + count, fill -= count);
316	}	334	}
317		335
318	bool byte_stream::put (u8 *data, unsigned int datalen)	336	bool byte_stream::put (u8 *data, unsigned int datalen)
…		…
331	return false;	349	return false;
332		350
333	data [fill++] = pkt->len >> 8;	351	data [fill++] = pkt->len >> 8;
334	data [fill++] = pkt->len;	352	data [fill++] = pkt->len;
335		353
336	memcpy (data + fill, &((*pkt)[0]), pkt->len); fill += pkt->len;	354	memcpy (data + fill, pkt->at (0), pkt->len); fill += pkt->len;
337		355
338	return true;	356	return true;
339	}	357	}
340		358
341	vpn_packet *byte_stream::get ()	359	vpn_packet *byte_stream::get ()
342	{	360	{
		361	unsigned int len;
		362
		363	for (;;)
		364	{
343	int len = (data [0] << 8) \| data [1];	365	len = (data [0] << 8) \| data [1];
344		366
345	if (len > MAXSIZE && fill >= 2)	367	if (len <= MAXSIZE \|\| fill < 2)
346	abort (); // TODO handle this gracefully, connection reset	368	break;
347		369
		370	// TODO: handle this better than skipping, e.g. by reset
		371	slog (L_DEBUG, _("DNS: corrupted packet stream skipping a byte..."));
		372	remove (1);
		373	}
		374
348	if (fill < len + 2)	375	if (fill < len + 2)
349	return 0;	376	return 0;
350		377
351	vpn_packet *pkt = new vpn_packet;	378	vpn_packet *pkt = new vpn_packet;
352		379
353	pkt->len = len;	380	pkt->len = len;
354	memcpy (&((*pkt)[0]), data + 2, len);	381	memcpy (pkt->at (0), data + 2, len);
355	remove (len + 2);	382	remove (len + 2);
356		383
357	return pkt;	384	return pkt;
358	}	385	}
359		386
…		…
376	#define FLAG_RCODE_REFUSED ( 5 << 0)	403	#define FLAG_RCODE_REFUSED ( 5 << 0)
377		404
378	#define DEFAULT_CLIENT_FLAGS (FLAG_QUERY \| FLAG_OP_QUERY \| FLAG_RD)	405	#define DEFAULT_CLIENT_FLAGS (FLAG_QUERY \| FLAG_OP_QUERY \| FLAG_RD)
379	#define DEFAULT_SERVER_FLAGS (FLAG_RESPONSE \| FLAG_OP_QUERY \| FLAG_AA \| FLAG_RD \| FLAG_RA)	406	#define DEFAULT_SERVER_FLAGS (FLAG_RESPONSE \| FLAG_OP_QUERY \| FLAG_AA \| FLAG_RD \| FLAG_RA)
380		407
		408	struct dns_cfg
		409	{
		410	static int next_uid;
		411
		412	u8 id1, id2, id3, id4;
		413	u8 version;
		414	u8 rrtype;
		415	u8 flags;
		416	u8 def_ttl;
		417	u8 rcv_cdc;
		418	u8 snd_cdc;
		419	u16 max_size;
		420	u16 client;
		421	u16 uid; // to make request unique
		422
		423	u8 reserved[8];
		424
		425	void reset (int clientid);
		426	bool valid ();
		427	};
		428
		429	int dns_cfg::next_uid;
		430
		431	void dns_cfg::reset (int clientid)
		432	{
		433	id1 = 'G';
		434	id2 = 'V';
		435	id3 = 'P';
		436	id4 = 'E';
		437
		438	version = 1;
		439
		440	rrtype = RR_TYPE_TXT;
		441	flags = 0;
		442	def_ttl = 1;
		443	rcv_cdc = 0;
		444	snd_cdc = 62;
		445	max_size = ntohs (MAX_PKT_SIZE);
		446	client = ntohs (clientid);
		447	uid = next_uid++;
		448
		449	memset (reserved, 0, 8);
		450	}
		451
		452	bool dns_cfg::valid ()
		453	{
		454	return id1 == 'G'
		455	&& id2 == 'V'
		456	&& id3 == 'P'
		457	&& id4 == 'E'
		458	&& version == 1
		459	&& flags == 0
		460	&& rcv_cdc == 0
		461	&& snd_cdc == 62
		462	&& max_size == ntohs (MAX_PKT_SIZE);
		463	}
		464
381	struct dns_packet : net_packet	465	struct dns_packet : net_packet
382	{	466	{
383	u16 id;	467	u16 id;
384	u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4	468	u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4
385	u16 qdcount, ancount, nscount, arcount;	469	u16 qdcount, ancount, nscount, arcount;
…		…
423	return data - orig;	507	return data - orig;
424	}	508	}
425		509
426	/////////////////////////////////////////////////////////////////////////////	510	/////////////////////////////////////////////////////////////////////////////
427		511
428	struct dns_req
429	{
430	dns_packet *pkt;
431	tstamp next;
432	int retry;
433	struct dns_connection *dns;
434	int seqno;
435
436	dns_req (dns_connection *dns);
437	void gen_stream_req (int seqno, byte_stream &stream);
438	};
439
440	static u16 dns_id = 12098; // TODO: should be per-vpn	512	static u16 dns_id = 0; // TODO: should be per-vpn
441		513
442	static u16 next_id ()	514	static u16 next_id ()
443	{	515	{
		516	if (!dns_id)
		517	dns_id = time (0);
		518
444	// the simplest lsfr with periodicity 65535 i could find	519	// the simplest lsfr with periodicity 65535 i could find
445	dns_id = (dns_id << 1)	520	dns_id = (dns_id << 1)
446	\| (((dns_id >> 1)	521	\| (((dns_id >> 1)
447	^ (dns_id >> 2)	522	^ (dns_id >> 2)
448	^ (dns_id >> 4)	523	^ (dns_id >> 4)
449	^ (dns_id >> 15)) & 1);	524	^ (dns_id >> 15)) & 1);
450		525
451	return dns_id;	526	return dns_id;
452	}	527	}
453		528
		529	struct dns_rcv;
		530	struct dns_snd;
		531
		532	struct dns_connection
		533	{
		534	connection *c;
		535	struct vpn *vpn;
		536
		537	dns_cfg cfg;
		538
		539	bool established;
		540
		541	tstamp last_received;
		542	tstamp last_sent;
		543	double last_latency;
		544	double poll_interval, send_interval;
		545
		546	vector<dns_rcv *> rcvpq;
		547
		548	byte_stream rcvdq; int rcvseq;
		549	byte_stream snddq; int sndseq;
		550
		551	void time_cb (time_watcher &w); time_watcher tw;
		552	void receive_rep (dns_rcv *r);
		553
		554	dns_connection (connection *c);
		555	~dns_connection ();
		556	};
		557
		558	struct dns_snd
		559	{
		560	dns_packet *pkt;
		561	tstamp timeout, sent;
		562	int retry;
		563	struct dns_connection *dns;
		564	int seqno;
		565	bool stdhdr;
		566
		567	void gen_stream_req (int seqno, byte_stream &stream);
		568	void gen_syn_req ();
		569
		570	dns_snd (dns_connection *dns);
		571	~dns_snd ();
		572	};
		573
454	dns_req::dns_req (dns_connection *dns)	574	dns_snd::dns_snd (dns_connection *dns)
455	: dns (dns)	575	: dns (dns)
456	{	576	{
457	next = 0;	577	timeout = 0;
458	retry = 0;	578	retry = 0;
		579	seqno = 0;
		580	sent = NOW;
		581	stdhdr = false;
459		582
460	pkt = new dns_packet;	583	pkt = new dns_packet;
461		584
462	pkt->id = next_id ();	585	pkt->id = next_id ();
463	}	586	}
464		587
		588	dns_snd::~dns_snd ()
		589	{
		590	delete pkt;
		591	}
		592
		593	static void append_domain (dns_packet &pkt, int &offs, const char *domain)
		594	{
		595	// add tunnel domain
		596	for (;;)
		597	{
		598	const char *end = strchr (domain, '.');
		599
		600	if (!end)
		601	end = domain + strlen (domain);
		602
		603	int len = end - domain;
		604
		605	pkt [offs++] = len;
		606	memcpy (pkt.at (offs), domain, len);
		607	offs += len;
		608
		609	if (!*end)
		610	break;
		611
		612	domain = end + 1;
		613	}
		614	}
		615
465	void dns_req::gen_stream_req (int seqno, byte_stream &stream)	616	void dns_snd::gen_stream_req (int seqno, byte_stream &stream)
466	{	617	{
		618	stdhdr = true;
467	this->seqno = seqno;	619	this->seqno = seqno;
		620
		621	timeout = NOW + INITIAL_TIMEOUT;
468		622
469	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	623	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
470	pkt->qdcount = htons (1);	624	pkt->qdcount = htons (1);
471		625
472	int offs = 6*2;	626	int offs = 6*2;
…		…
496	encp += lbllen;	650	encp += lbllen;
497		651
498	enclen -= lbllen;	652	enclen -= lbllen;
499	}	653	}
500		654
501	const char *suffix = THISNODE->domain;	655	append_domain (*pkt, offs, THISNODE->domain);
502
503	// add tunnel domain
504	for (;;)
505	{
506	const char *end = strchr (suffix, '.');
507
508	if (!end)
509	end = suffix + strlen (suffix);
510
511	int len = end - suffix;
512
513	(*pkt)[offs++] = len;
514	memcpy (&((*pkt)[offs]), suffix, len);
515	offs += len;
516
517	if (!*end)
518	break;
519
520	suffix = end + 1;
521	}
522		656
523	(*pkt)[offs++] = 0;	657	(*pkt)[offs++] = 0;
524	(pkt)[offs++] = RR_TYPE_ANY >> 8; (pkt)[offs++] = RR_TYPE_ANY;	658	(pkt)[offs++] = RR_TYPE_ANY >> 8; (pkt)[offs++] = RR_TYPE_ANY;
		659	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
		660
		661	pkt->len = offs;
		662	}
		663
		664	void dns_snd::gen_syn_req ()
		665	{
		666	timeout = NOW + INITIAL_SYN_TIMEOUT;
		667
		668	printf ("send syn\n");//D
		669
		670	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
		671	pkt->qdcount = htons (1);
		672
		673	int offs = 6 * 2;
		674
		675	int elen = cdc26.encode ((char )pkt->at (offs + 1), (u8 )&dns->cfg, sizeof (dns_cfg));
		676
		677	assert (elen <= MAX_LBL_SIZE);
		678
		679	(*pkt)[offs] = elen;
		680	offs += elen + 1;
		681	append_domain (*pkt, offs, THISNODE->domain);
		682
		683	(*pkt)[offs++] = 0;
		684	(pkt)[offs++] = RR_TYPE_A >> 8; (pkt)[offs++] = RR_TYPE_A;
525	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;	685	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
526		686
527	pkt->len = offs;	687	pkt->len = offs;
528	}	688	}
529		689
…		…
549	delete pkt;	709	delete pkt;
550	}	710	}
551		711
552	/////////////////////////////////////////////////////////////////////////////	712	/////////////////////////////////////////////////////////////////////////////
553		713
554	struct dns_connection
555	{
556	connection *c;
557	struct vpn *vpn;
558
559	vector<dns_rcv *> rcvpq;
560
561	int rcvseq;
562	int sndseq;
563
564	byte_stream rcvdq;
565	byte_stream snddq;
566
567	void time_cb (time_watcher &w); time_watcher tw;
568	void receive_rep (dns_rcv *r);
569
570	dns_connection (connection *c);
571	~dns_connection ();
572	};
573
574	dns_connection::dns_connection (connection *c)	714	dns_connection::dns_connection (connection *c)
575	: c (c)	715	: c (c)
576	, rcvdq (MAX_BACKLOG * 2)	716	, rcvdq (MAX_BACKLOG * 2)
577	, snddq (MAX_BACKLOG * 2)	717	, snddq (MAX_BACKLOG * 2)
578	, tw (this, &dns_connection::time_cb)	718	, tw (this, &dns_connection::time_cb)
579	{	719	{
580	vpn = c->vpn;	720	vpn = c->vpn;
581		721
		722	established = false;
		723
582	rcvseq = sndseq = 0;	724	rcvseq = sndseq = 0;
		725
		726	last_sent = last_received = 0;
		727	poll_interval = MIN_POLL_INTERVAL;
		728	send_interval = 0.5; // starting rate
		729	last_latency = INITIAL_TIMEOUT;
583	}	730	}
584		731
585	dns_connection::~dns_connection ()	732	dns_connection::~dns_connection ()
586	{	733	{
587	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();	734	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();
588	i != rcvpq.end ();	735	i != rcvpq.end ();
589	++i)	736	++i)
590	delete *i;	737	delete *i;
591	}	738	}
592		739
593	struct dns_cfg
594	{
595	u8 id1, id2, id3;
596	u8 def_ttl;
597	u8 unused1;
598	u16 max_size;
599	u8 flags1, flags2;
600	};
601
602	void dns_connection::receive_rep (dns_rcv *r)	740	void dns_connection::receive_rep (dns_rcv *r)
603	{	741	{
		742	if (r->datalen)
		743	{
		744	last_received = NOW;
		745	tw.trigger ();
		746
		747	poll_interval = send_interval;
		748	}
		749	else
		750	{
		751	poll_interval *= 1.5;
		752	if (poll_interval > MAX_POLL_INTERVAL)
		753	poll_interval = MAX_POLL_INTERVAL;
		754	}
		755
604	rcvpq.push_back (r);	756	rcvpq.push_back (r);
605		757
606	redo:	758	redo:
607		759
608	// find next packet	760	// find next packet
…		…
622	}	774	}
623		775
624	rcvseq = (rcvseq + 1) & SEQNO_MASK;	776	rcvseq = (rcvseq + 1) & SEQNO_MASK;
625		777
626	if (!rcvdq.put (r->data, r->datalen))	778	if (!rcvdq.put (r->data, r->datalen))
		779	{
		780	slog (L_ERR, "DNS: !rcvdq.put (r->data, r->datalen)");
627	abort (); // MUST never overflow, can be caused by data corruption, TODO	781	abort (); // MUST never overflow, can be caused by data corruption, TODO
		782	}
628		783
629	while (vpn_packet *pkt = rcvdq.get ())	784	while (vpn_packet *pkt = rcvdq.get ())
630	{	785	{
631	sockinfo si;	786	sockinfo si;
632	si.host = 0; si.port = 0; si.prot = PROT_DNSv4;	787	si.host = 0x01010101; si.port = htons (c->conf->id); si.prot = PROT_DNSv4;
633		788
634	vpn->recv_vpn_packet (pkt, si);	789	vpn->recv_vpn_packet (pkt, si);
		790
		791	delete pkt;
635	}	792	}
636		793
637	// check for further packets	794	// check for further packets
638	goto redo;	795	goto redo;
639	}	796	}
640	}	797	}
641		798
642	dns_packet *	799	void
643	vpn::dnsv4_server (dns_packet *pkt)	800	vpn::dnsv4_server (dns_packet &pkt)
644	{	801	{
645	u16 flags = ntohs (pkt->flags);	802	u16 flags = ntohs (pkt.flags);
646		803
647	//memcpy (&((rep)[0]), &((pkt)[0]), pkt->len);
648	int offs = 6 * 2; // skip header	804	int offs = 6 * 2; // skip header
649		805
650	pkt->flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);	806	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);
651		807
652	if (0 == (flags & (FLAG_RESPONSE \| FLAG_OP_MASK \| FLAG_TC))	808	if (0 == (flags & (FLAG_RESPONSE \| FLAG_OP_MASK))
653	&& pkt->qdcount == htons (1))	809	&& pkt.qdcount == htons (1))
654	{	810	{
655	char qname[MAXSIZE];	811	char qname[MAXSIZE];
656	int qlen = pkt->decode_label ((char *)qname, MAXSIZE - offs, offs);	812	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
657		813
658	u16 qtype = (pkt) [offs++] << 8; qtype \|= (pkt) [offs++];	814	u16 qtype = pkt [offs++] << 8; qtype \|= pkt [offs++];
659	u16 qclass = (pkt) [offs++] << 8; qclass \|= (pkt) [offs++];	815	u16 qclass = pkt [offs++] << 8; qclass \|= pkt [offs++];
660		816
661	pkt->qdcount = htons (1);	817	pkt.qdcount = htons (1);
662	pkt->ancount = 0;	818	pkt.ancount = 0;
663	pkt->nscount = 0; // should be self, as other nameservers reply like this	819	pkt.nscount = 0; // should be self, as other nameservers reply like this
664	pkt->arcount = 0; // a record for self, as other nameservers reply like this	820	pkt.arcount = 0; // a record for self, as other nameservers reply like this
665		821
666	pkt->flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_NXDOMAIN);	822	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_SERVFAIL);
667		823
668	int dlen = strlen (THISNODE->domain);	824	int dlen = strlen (THISNODE->domain);
669		825
670	if (qclass == RR_CLASS_IN	826	if (qclass == RR_CLASS_IN
671	&& (qtype == RR_TYPE_ANY \|\| qtype == RR_TYPE_TXT)
672	&& qlen > dlen + 1 + HDRSIZE	827	&& qlen > dlen + 1
673	&& !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen))	828	&& !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen))
674	{	829	{
675	// correct class, domain: parse	830	// now generate reply
676	int client, seqno;	831	pkt.ancount = htons (1); // one answer RR
677	decode_header (qname, client, seqno);	832	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_OK);
678		833
679	u8 data[MAXSIZE];	834	if ((qtype == RR_TYPE_ANY
680	int datalen = cdc62.decode (data, qname + HDRSIZE, qlen - (dlen + 1 + HDRSIZE));	835	\|\| qtype == RR_TYPE_TXT
681		836	\|\| qtype == RR_TYPE_NULL)
682	if (0 < client && client <= conns.size ())	837	&& qlen > dlen + 1 + HDRSIZE)
683	{	838	{
684	connection *c = conns [client - 1];	839	// correct class, domain: parse
		840	int client, seqno;
		841	decode_header (qname, client, seqno);
685		842
686	if (!c->dns)	843	u8 data[MAXSIZE];
687	c->dns = new dns_connection (c);	844	int datalen = cdc62.decode (data, qname + HDRSIZE, qlen - (dlen + 1 + HDRSIZE));
688		845
689	dns_connection *dns = c->dns;	846	if (0 < client && client <= conns.size ())
690
691	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )
692	if (SEQNO_EQ ((*i)->seqno, seqno))
693	{
694	// already seen that request: simply reply with the cached reply
695	dns_rcv r = i;
696
697	printf ("DUPLICATE %d\n", htons (r->pkt->id));//D
698
699	memcpy (pkt->at (0), r->pkt->at (0), offs = r->pkt->len);
700	pkt->id = r->pkt->id;
701	goto duplicate_request;
702	}
703
704	// new packet, queue
705	dns_rcv *rcv = new dns_rcv (seqno, data, datalen);
706	dns->receive_rep (rcv);
707
708	// now generate reply
709	pkt->ancount = htons (1); // one answer RR
710	pkt->flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_OK);
711
712	(*pkt) [offs++] = 0xc0;
713	(pkt) [offs++] = 6 2; // same as in query section
714
715	(pkt) [offs++] = RR_TYPE_TXT >> 8; (pkt) [offs++] = RR_TYPE_TXT;
716	(pkt) [offs++] = RR_CLASS_IN >> 8; (pkt) [offs++] = RR_CLASS_IN;
717
718	(pkt) [offs++] = 0; (pkt) [offs++] = 0;
719	(pkt) [offs++] = 0; (pkt) [offs++] = 0; // TTL
720
721	int dlen = MAX_PKT_SIZE - offs - 2;
722
723	// bind doesn't compress well, so reduce further by one label length
724	dlen -= qlen;
725
726	int rdlen_offs = offs += 2;
727
728	while (dlen > 1 && !dns->snddq.empty ())
729	{	847	{
		848	connection *c = conns [client - 1];
		849	dns_connection *dns = c->dns;
		850	dns_rcv *rcv;
		851	bool in_seq;
		852
		853	if (dns)
		854	{
		855	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )
		856	if (SEQNO_EQ ((*i)->seqno, seqno))
		857	{
		858	// already seen that request: simply reply with the cached reply
		859	dns_rcv r = i;
		860
		861	slog (L_DEBUG, "DNS: duplicate packet received ID %d, SEQ %d", htons (r->pkt->id), seqno);
		862
		863	// refresh header & id, as the retry count could have changed
		864	memcpy (r->pkt->at (6 * 2 + 1), pkt.at (6 * 2 + 1), HDRSIZE);
		865	r->pkt->id = pkt.id;
		866
		867	memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len);
		868
		869	goto duplicate_request;
		870	}
		871
		872	in_seq = dns->rcvseq == seqno;
		873
		874	// new packet, queue
		875	rcv = new dns_rcv (seqno, data, datalen);
		876	dns->receive_rep (rcv);
		877	}
		878
		879	pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section
		880
		881	int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A;
		882	pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type
		883	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
		884	pkt [offs++] = 0; pkt [offs++] = 0;
		885	pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL
		886
		887	int rdlen_offs = offs += 2;
		888
		889	int dlen = (dns ? ntohs (dns->cfg.max_size) : MAX_PKT_SIZE) - offs;
		890	// bind doesn't compress well, so reduce further by one label length
		891	dlen -= qlen;
		892
		893	if (dns)
		894	{
		895	// only put data into in-order sequence packets, if
		896	// we receive out-of-order packets we generate empty
		897	// replies
		898	while (dlen > 1 && !dns->snddq.empty () && in_seq)
		899	{
730	int txtlen = dlen <= 255 ? dlen - 1 : 255;	900	int txtlen = dlen <= 255 ? dlen - 1 : 255;
731		901
732	if (txtlen > dns->snddq.size ())	902	if (txtlen > dns->snddq.size ())
733	txtlen = dns->snddq.size ();	903	txtlen = dns->snddq.size ();
734		904
735	(*pkt)[offs++] = txtlen;	905	pkt[offs++] = txtlen;
736	memcpy (pkt->at (offs), dns->snddq.begin (), txtlen);	906	memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);
737	offs += txtlen;	907	offs += txtlen;
738	dns->snddq.remove (txtlen);	908	dns->snddq.remove (txtlen);
739		909
740	dlen -= txtlen + 1;	910	dlen -= txtlen + 1;
		911	}
		912
		913	// avoid empty TXT rdata
		914	if (offs == rdlen_offs)
		915	pkt[offs++] = 0;
		916
		917	slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ());
		918	}
		919	else
		920	{
		921	// send RST
		922	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
		923	pkt [offs++] = CMD_IP_RST;
		924	}
		925
		926	int rdlen = offs - rdlen_offs;
		927
		928	pkt [rdlen_offs - 2] = rdlen >> 8;
		929	pkt [rdlen_offs - 1] = rdlen;
		930
		931	if (dns)
		932	{
		933	// now update dns_rcv copy
		934	rcv->pkt->len = offs;
		935	memcpy (rcv->pkt->at (0), pkt.at (0), offs);
		936	}
		937
		938	duplicate_request: ;
741	}	939	}
742		940	else
743	// avoid empty TXT rdata	941	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);
744	if (offs == rdlen_offs)
745	(*pkt)[offs++] = 0;
746
747	int rdlen = offs - rdlen_offs;
748
749	(*pkt) [rdlen_offs - 2] = rdlen >> 8;
750	(*pkt) [rdlen_offs - 1] = rdlen;
751
752	// now update dns_rcv copy
753	rcv->pkt->len = offs;
754	memcpy (rcv->pkt->at (0), pkt->at (0), offs);
755
756	duplicate_request: ;
757	}	942	}
758	else	943	else if (qtype == RR_TYPE_A
759	pkt->flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);	944	&& qlen > dlen + 1 + cdc26.encode_len (sizeof (dns_cfg)))
		945	{
		946	dns_cfg cfg;
		947	cdc26.decode ((u8 *)&cfg, qname, cdc26.encode_len (sizeof (dns_cfg)));
		948	int client = ntohs (cfg.client);
		949
		950	pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section
		951
		952	pkt [offs++] = RR_TYPE_A >> 8; pkt [offs++] = RR_TYPE_A; // type
		953	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
		954	pkt [offs++] = 0; pkt [offs++] = 0;
		955	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL
		956	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength
		957
		958	slog (L_INFO, _("DNS: client %d tries to connect"), client);
		959
		960	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
		961	pkt [offs++] = CMD_IP_REJ;
		962
		963	if (0 < client && client <= conns.size ())
		964	{
		965	connection *c = conns [client - 1];
		966
		967	if (cfg.valid ())
		968	{
		969	pkt [offs - 1] = CMD_IP_SYN;
		970
		971	delete c->dns;
		972	c->dns = new dns_connection (c);
		973	c->dns->cfg = cfg;
		974	}
		975	}
		976	}
760	}	977	}
761		978
762	pkt->len = offs;	979	pkt.len = offs;
763	}	980	}
764
765	return pkt;
766	}	981	}
767		982
768	void	983	void
769	vpn::dnsv4_client (dns_packet *pkt)	984	vpn::dnsv4_client (dns_packet &pkt)
770	{	985	{
771	u16 flags = ntohs (pkt->flags);	986	u16 flags = ntohs (pkt.flags);
772	int offs = 6 * 2; // skip header	987	int offs = 6 * 2; // skip header
773		988
774	pkt->qdcount = ntohs (pkt->qdcount);	989	pkt.qdcount = ntohs (pkt.qdcount);
775	pkt->ancount = ntohs (pkt->ancount);	990	pkt.ancount = ntohs (pkt.ancount);
776		991
777	// go through our request list and find the corresponding request	992	// go through our request list and find the corresponding request
778	for (vector<dns_req *>::iterator i = dns_sndpq.begin ();	993	for (vector<dns_snd *>::iterator i = dns_sndpq.begin ();
779	i != dns_sndpq.end ();	994	i != dns_sndpq.end ();
780	++i)	995	++i)
781	if ((*i)->pkt->id == pkt->id)	996	if ((*i)->pkt->id == pkt.id)
782	{	997	{
783	dns_connection dns = (i)->dns;	998	dns_connection dns = (i)->dns;
		999	connection *c = dns->c;
784	int seqno = (*i)->seqno;	1000	int seqno = (*i)->seqno;
785	u8 data[MAXSIZE], *datap = data;	1001	u8 data[MAXSIZE], *datap = data;
786		1002
		1003	if ((*i)->retry)
		1004	{
		1005	dns->send_interval *= 1.01;
		1006	if (dns->send_interval > MAX_SEND_INTERVAL)
		1007	dns->send_interval = MAX_SEND_INTERVAL;
		1008	}
		1009	else
		1010	{
		1011	#if 1
		1012	dns->send_interval *= 0.999;
		1013	#endif
		1014	if (dns->send_interval < MIN_SEND_INTERVAL)
		1015	dns->send_interval = MIN_SEND_INTERVAL;
		1016
		1017	// the latency surely puts an upper bound on
		1018	// the minimum send interval
		1019	double latency = NOW - (*i)->sent;
		1020	dns->last_latency = latency;
		1021
		1022	if (dns->send_interval > latency)
		1023	dns->send_interval = latency;
		1024	}
		1025
787	delete *i;	1026	delete *i;
788	dns_sndpq.erase (i);	1027	dns_sndpq.erase (i);
789		1028
790	if (flags & FLAG_RESPONSE && !(flags & (FLAG_OP_MASK \| FLAG_TC)))	1029	if (flags & FLAG_RESPONSE && !(flags & FLAG_OP_MASK))
791	{	1030	{
792	char qname[MAXSIZE];	1031	char qname[MAXSIZE];
793		1032
794	while (pkt->qdcount-- && offs < MAXSIZE - 4)	1033	while (pkt.qdcount-- && offs < MAXSIZE - 4)
795	{	1034	{
796	int qlen = pkt->decode_label ((char *)qname, MAXSIZE - offs, offs);	1035	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
797	offs += 4; // skip qtype, qclass	1036	offs += 4; // skip qtype, qclass
798	}	1037	}
799		1038
800	while (pkt->ancount-- && offs < MAXSIZE - 10 && datap)	1039	while (pkt.ancount-- && offs < MAXSIZE - 10 && datap)
801	{	1040	{
802	int qlen = pkt->decode_label ((char *)qname, MAXSIZE - offs, offs);	1041	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
803		1042
804	u16 qtype = (pkt) [offs++] << 8; qtype \|= (pkt) [offs++];	1043	u16 qtype = pkt [offs++] << 8; qtype \|= pkt [offs++];
805	u16 qclass = (pkt) [offs++] << 8; qclass \|= (pkt) [offs++];	1044	u16 qclass = pkt [offs++] << 8; qclass \|= pkt [offs++];
806	u32 ttl = (*pkt) [offs++] << 24;	1045	u32 ttl = pkt [offs++] << 24;
807	ttl \|= (*pkt) [offs++] << 16;	1046	ttl \|= pkt [offs++] << 16;
808	ttl \|= (*pkt) [offs++] << 8;	1047	ttl \|= pkt [offs++] << 8;
809	ttl \|= (*pkt) [offs++];	1048	ttl \|= pkt [offs++];
810
811	u16 rdlen = (pkt) [offs++] << 8; rdlen \|= (pkt) [offs++];	1049	u16 rdlen = pkt [offs++] << 8; rdlen \|= pkt [offs++];
812		1050
813	if (rdlen <= MAXSIZE - offs)	1051	if (qtype == RR_TYPE_NULL \|\| qtype == RR_TYPE_TXT)
814	{	1052	{
815	// decode bytes, finally	1053	if (rdlen <= MAXSIZE - offs)
816
817	while (rdlen)
818	{	1054	{
		1055	// decode bytes, finally
		1056
		1057	while (rdlen)
		1058	{
819	int txtlen = (*pkt) [offs++];	1059	int txtlen = pkt [offs++];
820		1060
821	assert (txtlen + offs < MAXSIZE - 1);	1061	assert (txtlen + offs < MAXSIZE - 1);
822		1062
823	memcpy (datap, pkt->at (offs), txtlen);	1063	memcpy (datap, pkt.at (offs), txtlen);
824	datap += txtlen; offs += txtlen;	1064	datap += txtlen; offs += txtlen;
825		1065
826	rdlen -= txtlen + 1;	1066	rdlen -= txtlen + 1;
		1067	}
827	}	1068	}
828	}	1069	}
		1070	else if (qtype == RR_TYPE_A)
		1071	{
		1072	u8 ip [4];
		1073
		1074	ip [0] = pkt [offs++];
		1075	ip [1] = pkt [offs++];
		1076	ip [2] = pkt [offs++];
		1077	ip [3] = pkt [offs++];
		1078
		1079	if (ip [0] == CMD_IP_1
		1080	&& ip [1] == CMD_IP_2
		1081	&& ip [2] == CMD_IP_3)
		1082	{
		1083	slog (L_TRACE, _("DNS: got tunnel meta command %02x"), ip [3]);
		1084
		1085	if (ip [3] == CMD_IP_RST)
		1086	{
		1087	slog (L_DEBUG, _("DNS: got tunnel RST request"));
		1088
		1089	delete dns; c->dns = 0;
		1090
		1091	return;
		1092	}
		1093	else if (ip [3] == CMD_IP_SYN)
		1094	{
		1095	slog (L_DEBUG, _("DNS: got tunnel SYN reply, server likes us."));
		1096	dns->established = true;
		1097	}
		1098	else if (ip [3] == CMD_IP_REJ)
		1099	{
		1100	slog (L_DEBUG, _("DNS: got tunnel REJ reply, server does not like us, aborting."));
		1101	abort ();
		1102	}
		1103	else
		1104	slog (L_INFO, _("DNS: got unknown meta command %02x"), ip [3]);
		1105	}
		1106	else
		1107	slog (L_INFO, _("DNS: got spurious a record %d.%d.%d.%d"),
		1108	ip [0], ip [1], ip [2], ip [3]);
		1109
		1110	return;
		1111	}
829		1112
830	int client, rseqno;	1113	int client, rseqno;
831	decode_header (qname, client, rseqno);	1114	decode_header (qname, client, rseqno);
832		1115
833	if (client != THISNODE->id)	1116	if (client != THISNODE->id)
834	{	1117	{
835	slog (L_INFO, _("got dns tunnel response with wrong clientid, ignoring"));	1118	slog (L_INFO, _("DNS: got dns tunnel response with wrong clientid, ignoring"));
836	datap = 0;	1119	datap = 0;
837	}	1120	}
838	else if (rseqno != seqno)	1121	else if (rseqno != seqno)
839	{	1122	{
840	slog (L_DEBUG, _("got dns tunnel response with wrong seqno, badly caching nameserver?"));	1123	slog (L_DEBUG, _("DNS: got dns tunnel response with wrong seqno, badly caching nameserver?"));
841	datap = 0;	1124	datap = 0;
842	}	1125	}
843	}	1126	}
844	}	1127	}
845		1128
…		…
847	if (datap)	1130	if (datap)
848	dns->receive_rep (new dns_rcv (seqno, data, datap - data));	1131	dns->receive_rep (new dns_rcv (seqno, data, datap - data));
849		1132
850	break;	1133	break;
851	}	1134	}
852
853	delete pkt;
854	}	1135	}
855		1136
856	void	1137	void
857	vpn::dnsv4_ev (io_watcher &w, short revents)	1138	vpn::dnsv4_ev (io_watcher &w, short revents)
858	{	1139	{
…		…
860	{	1141	{
861	dns_packet *pkt = new dns_packet;	1142	dns_packet *pkt = new dns_packet;
862	struct sockaddr_in sa;	1143	struct sockaddr_in sa;
863	socklen_t sa_len = sizeof (sa);	1144	socklen_t sa_len = sizeof (sa);
864		1145
865	pkt->len = recvfrom (w.fd, &((pkt)[0]), MAXSIZE, 0, (sockaddr )&sa, &sa_len);	1146	pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len);
866		1147
867	if (pkt->len > 0)	1148	if (pkt->len > 0)
868	{	1149	{
869	if (pkt->flags & htons (FLAG_TC))
870	{
871	slog (L_WARN, _("DNS request/response truncated, check protocol settings."));
872	//TODO connection reset
873	}
874
875	if (THISNODE->dns_port)	1150	if (THISNODE->dns_port)
876	{	1151	{
877	pkt = dnsv4_server (pkt);	1152	dnsv4_server (*pkt);
878	sendto (w.fd, &((pkt)[0]), pkt->len, 0, (sockaddr )&sa, sa_len);	1153	sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len);
879	}	1154	}
880	else	1155	else
881	dnsv4_client (pkt);	1156	dnsv4_client (*pkt);
		1157
		1158	delete pkt;
882	}	1159	}
883	}	1160	}
884	}	1161	}
885		1162
886	bool	1163	bool
887	connection::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)	1164	vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)
888	{	1165	{
		1166	int client = ntohs (si.port);
		1167
		1168	assert (0 < client && client <= conns.size ());
		1169
		1170	connection *c = conns [client - 1];
		1171
889	if (!dns)	1172	if (!c->dns)
890	dns = new dns_connection (this);	1173	c->dns = new dns_connection (c);
891		1174
892	if (!dns->snddq.put (pkt))	1175	if (!c->dns->snddq.put (pkt))
893	return false;	1176	return false;
894		1177
895	// start timer if neccessary
896	if (!THISNODE->dns_port && !dns->tw.active)
897	dns->tw.trigger ();	1178	c->dns->tw.trigger ();
898		1179
899	return true;	1180	return true;
900	}	1181	}
		1182
		1183	void
		1184	connection::dnsv4_reset_connection ()
		1185	{
		1186	//delete dns; dns = 0; //TODO
		1187	}
		1188
		1189	#define NEXT(w) do { if (next > (w)) next = w; } while (0)
901		1190
902	void	1191	void
903	dns_connection::time_cb (time_watcher &w)	1192	dns_connection::time_cb (time_watcher &w)
904	{	1193	{
		1194	// servers have to be polled
		1195	if (THISNODE->dns_port)
		1196	return;
		1197
905	// check for timeouts and (re)transmit	1198	// check for timeouts and (re)transmit
906	tstamp next = NOW + 60;	1199	tstamp next = NOW + poll_interval;
907	dns_req *send = 0;	1200	dns_snd *send = 0;
908		1201
909	for (vector<dns_req *>::iterator i = vpn->dns_sndpq.begin ();	1202	for (vector<dns_snd *>::iterator i = vpn->dns_sndpq.begin ();
910	i != vpn->dns_sndpq.end ();	1203	i != vpn->dns_sndpq.end ();
911	++i)	1204	++i)
912	{	1205	{
913	dns_req r = i;	1206	dns_snd r = i;
914		1207
915	if (r->next <= NOW)	1208	if (r->timeout <= NOW)
916	{	1209	{
917	if (!send)	1210	if (!send)
918	{	1211	{
919	send = r;	1212	send = r;
920		1213
921	if (r->retry)//D
922	printf ("req %d:%d, retry %d\n", r->seqno, r->pkt->id, r->retry);
923	r->retry++;	1214	r->retry++;
924	r->next = NOW + r->retry;	1215	r->timeout = NOW + (r->retry * last_latency * 8.);
		1216
		1217	// the following code changes the query section a bit, forcing
		1218	// the forwarder to generate a new request
		1219	if (r->stdhdr)
		1220	{
		1221	//printf ("reencoded header for ID %d retry %d:%d:%d\n", htons (r->pkt->id), THISNODE->id, r->seqno, r->retry);printf ("reencoded header for ID %d retry %d:%d:%d\n", htons (r->pkt->id), THISNODE->id, r->seqno, r->retry);
		1222	//encode_header ((char )r->pkt->at (6 2 + 1), THISNODE->id, r->seqno, r->retry);
		1223	}
925	}	1224	}
926	}	1225	}
		1226	else
		1227	NEXT (r->timeout);
		1228	}
927		1229
928	if (r->next < next)	1230	if (last_sent + send_interval <= NOW)
929	next = r->next;
930	}	1231	{
931
932	if (!send	1232	if (!send)
		1233	{
		1234	// generate a new packet, if wise
		1235
		1236	if (!established)
		1237	{
		1238	if (vpn->dns_sndpq.empty ())
		1239	{
		1240	send = new dns_snd (this);
		1241
		1242	printf ("new conn %p %d\n", this, c->conf->id);//D
		1243	cfg.reset (THISNODE->id);
		1244	send->gen_syn_req ();
		1245	}
		1246	}
933	&& vpn->dns_sndpq.size () < MAX_OUTSTANDING)	1247	else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING
934	{	1248	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
		1249	{
		1250	//printf ("sending data request etc.\n"); //D
		1251	if (!snddq.empty ())
		1252	{
		1253	poll_interval = send_interval;
		1254	NEXT (NOW + send_interval);
		1255	}
		1256
935	send = new dns_req (this);	1257	send = new dns_snd (this);
936	send->gen_stream_req (sndseq, snddq);	1258	send->gen_stream_req (sndseq, snddq);
		1259	send->timeout = NOW + last_latency * 8.;
		1260
		1261	sndseq = (sndseq + 1) & SEQNO_MASK;
		1262	}
		1263
		1264	if (send)
937	vpn->dns_sndpq.push_back (send);	1265	vpn->dns_sndpq.push_back (send);
		1266	}
938		1267
939	sndseq = (sndseq + 1) & SEQNO_MASK;
940	}
941
942	tstamp min_next = NOW + (1. / (tstamp)MAX_RATE);
943
944	if (send)	1268	if (send)
945	{	1269	{
946	dns_packet *pkt = send->pkt;	1270	last_sent = NOW;
947		1271	sendto (vpn->dnsv4_fd,
948	next = min_next;	1272	send->pkt->at (0), send->pkt->len, 0,
949
950	sendto (vpn->dnsv4_fd, &((*pkt)[0]), pkt->len, 0,
951	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());	1273	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
		1274	}
952	}	1275	}
953	else if (next < min_next)	1276	else
954	next = min_next;	1277	NEXT (last_sent + send_interval);
		1278
		1279	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d)",
		1280	poll_interval, send_interval, next - NOW,
		1281	vpn->dns_sndpq.size (), snddq.size ());
		1282
		1283	// TODO: no idea when this happens, but when next < NOW, we have a problem
		1284	if (next < NOW + 0.0001)
		1285	next = NOW + 0.1;
955		1286
956	w.start (next);	1287	w.start (next);
957	}	1288	}
958		1289
959	#endif	1290	#endif

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Comparing gvpe/src/vpn_dns.C (file contents): Revision 1.9 by pcg, Fri Mar 4 04:52:38 2005 UTC vs. Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC

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Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.9 by pcg, Fri Mar 4 04:52:38 2005 UTC vs.
Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC