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

Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.40 by pcg, Sat Jul 9 20:29:29 2005 UTC vs.
Revision 1.51 by root, Sun Mar 6 19:40:28 2011 UTC

…		…
1	/*	1	/*
2	vpn_dns.C -- handle the dns tunnel part of the protocol.	2	vpn_dns.C -- handle the dns tunnel part of the protocol.
3	Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de>	3	Copyright (C) 2003-2011 Marc Lehmann <gvpe@schmorp.de>
4		4
5	This file is part of GVPE.	5	This file is part of GVPE.
6		6
7	GVPE is free software; you can redistribute it and/or modify	7	GVPE is free software; you can redistribute it and/or modify it
8	it under the terms of the GNU General Public License as published by	8	under the terms of the GNU General Public License as published by the
9	the Free Software Foundation; either version 2 of the License, or	9	Free Software Foundation; either version 3 of the License, or (at your
10	(at your option) any later version.	10	option) any later version.
11		11
12	This program is distributed in the hope that it will be useful,	12	This program is distributed in the hope that it will be useful, but
13	but WITHOUT ANY WARRANTY; without even the implied warranty of	13	WITHOUT ANY WARRANTY; without even the implied warranty of
14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
15	GNU General Public License for more details.	15	Public License for more details.
16		16
17	You should have received a copy of the GNU General Public License	17	You should have received a copy of the GNU General Public License along
18	along with gvpe; if not, write to the Free Software	18	with this program; if not, see <http://www.gnu.org/licenses/>.
19	Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA	19
		20	Additional permission under GNU GPL version 3 section 7
		21
		22	If you modify this Program, or any covered work, by linking or
		23	combining it with the OpenSSL project's OpenSSL library (or a modified
		24	version of that library), containing parts covered by the terms of the
		25	OpenSSL or SSLeay licenses, the licensors of this Program grant you
		26	additional permission to convey the resulting work. Corresponding
		27	Source for a non-source form of such a combination shall include the
		28	source code for the parts of OpenSSL used as well as that of the
		29	covered work.
20	*/	30	*/
21		31
22	// TODO: EDNS0 option to increase dns mtu?	32	// TODO: EDNS0 option to increase dns mtu?
23	// TODO: re-write dns packet parsing/creation using a safe mem-buffer	33	// TODO: re-write dns packet parsing/creation using a safe mem-buffer
24	// to ensure no buffer overflows or similar problems.	34	// to ensure no buffer overflows or similar problems.
42	#include <unistd.h>	52	#include <unistd.h>
43	#include <fcntl.h>	53	#include <fcntl.h>
44		54
45	#include <map>	55	#include <map>
46		56
		57	#include <cstdio> /* bug in libgmp: gmp.h relies on cstdio being included */
47	#include <gmp.h>	58	#include <gmp.h>
48		59
49	#include "netcompat.h"	60	#include "netcompat.h"
50		61
51	#include "vpn.h"	62	#include "vpn.h"
52		63
		64	#define MIN_POLL_INTERVAL 0.1 // poll at most this often when no data received
53	#define MAX_POLL_INTERVAL 5. // how often to poll minimally when the server has no data	65	#define MAX_POLL_INTERVAL 1. // how often to poll minimally when the server has no data
54	#define ACTIVITY_INTERVAL 5.
55		66
56	#define INITIAL_TIMEOUT 0.1 // retry timeouts	67	#define INITIAL_TIMEOUT 0.1 // retry timeouts
57	#define INITIAL_SYN_TIMEOUT 2. // retry timeout for initial syn	68	#define INITIAL_SYN_TIMEOUT 2. // retry timeout for initial syn
58		69
59	#define MAX_SEND_INTERVAL 2. // optimistic?	70	#define MAX_SEND_INTERVAL 2. // optimistic?
…		…
72	#define MAX_PKT_SIZE 512	83	#define MAX_PKT_SIZE 512
73		84
74	#define RR_TYPE_A 1	85	#define RR_TYPE_A 1
75	#define RR_TYPE_NULL 10	86	#define RR_TYPE_NULL 10
76	#define RR_TYPE_TXT 16	87	#define RR_TYPE_TXT 16
		88	#define RR_TYPE_AAAA 28
77	#define RR_TYPE_ANY 255	89	#define RR_TYPE_ANY 255
78		90
79	#define RR_CLASS_IN 1	91	#define RR_CLASS_IN 1
80		92
81	#define CMD_IP_1 207	93	#define CMD_IP_1 207
82	#define CMD_IP_2 46	94	#define CMD_IP_2 46
83	#define CMD_IP_3 236	95	#define CMD_IP_3 236
84	#define CMD_IP_RST 29	96
85	#define CMD_IP_SYN 113	97	#define CMD_IP_RST 29 // some error, reset and retry
86	#define CMD_IP_REJ 32	98	#define CMD_IP_REJ 32 // do not want you
		99	#define CMD_IP_SYN 113 // connection established
		100	#define CMD_IP_CSE 213 // connection established, but likely case mismatch
		101
		102	static bool
		103	is_uc (char c)
		104	{
		105	return 'A' <= c && c <= 'Z';
		106	}
		107
		108	static bool
		109	is_lc (char c)
		110	{
		111	return 'a' <= c && c <= 'z';
		112	}
87		113
88	// works for cmaps up to 255 (not 256!)	114	// works for cmaps up to 255 (not 256!)
89	struct charmap	115	struct charmap
90	{	116	{
91	enum { INVALID = (u8)255 };	117	enum { INVALID = (u8)255 };
…		…
105	memset (enc, (char) 0, 256);	131	memset (enc, (char) 0, 256);
106	memset (dec, (char)INVALID, 256);	132	memset (dec, (char)INVALID, 256);
107		133
108	for (size = 0; cmap [size]; size++)	134	for (size = 0; cmap [size]; size++)
109	{	135	{
		136	char c = cmap [size];
		137
110	enc [size] = cmap [size];	138	enc [size] = c;
111	dec [(u8)enc [size]] = size;	139	dec [(u8)c] = size;
		140
		141	// allow lowercase/uppercase aliases if possible
		142	if (is_uc (c) && dec [c + ('a' - 'A')] == INVALID) dec [c + ('a' - 'A')] = size;
		143	if (is_lc (c) && dec [c - ('a' - 'A')] == INVALID) dec [c - ('a' - 'A')] = size;
112	}	144	}
113		145
114	assert (size < 256);	146	assert (size < 256);
115	}	147	}
116		148
…		…
123	{	155	{
124	charmap cmap;	156	charmap cmap;
125	unsigned int enc_len [MAX_DEC_LEN];	157	unsigned int enc_len [MAX_DEC_LEN];
126	unsigned int dec_len [MAX_ENC_LEN];	158	unsigned int dec_len [MAX_ENC_LEN];
127		159
128	unsigned int encode_len (unsigned int len);	160	unsigned int encode_len (unsigned int len) const;
129	unsigned int decode_len (unsigned int len);	161	unsigned int decode_len (unsigned int len) const;
130		162
131	unsigned int encode (char dst, u8 src, unsigned int len);	163	unsigned int encode (char dst, u8 src, unsigned int len) const;
132	unsigned int decode (u8 dst, char src, unsigned int len);	164	unsigned int decode (u8 dst, char src, unsigned int len) const;
133		165
134	basecoder (const char *cmap);	166	basecoder (const char *cmap);
135	};	167	};
136		168
137	basecoder::basecoder (const char *cmap)	169	basecoder::basecoder (const char *cmap)
…		…
156	enc_len [len] = n;	188	enc_len [len] = n;
157	dec_len [n] = len;	189	dec_len [n] = len;
158	}	190	}
159	}	191	}
160		192
		193	unsigned int
161	unsigned int basecoder::encode_len (unsigned int len)	194	basecoder::encode_len (unsigned int len) const
162	{	195	{
163	return enc_len [len];	196	return enc_len [len];
164	}	197	}
165		198
		199	unsigned int
166	unsigned int basecoder::decode_len (unsigned int len)	200	basecoder::decode_len (unsigned int len) const
167	{	201	{
168	while (len && !dec_len [len])	202	while (len && !dec_len [len])
169	--len;	203	--len;
170		204
171	return dec_len [len];	205	return dec_len [len];
172	}	206	}
173		207
		208	unsigned int
174	unsigned int basecoder::encode (char dst, u8 src, unsigned int len)	209	basecoder::encode (char dst, u8 src, unsigned int len) const
175	{	210	{
176	if (!len \|\| len > MAX_DEC_LEN)	211	if (!len \|\| len > MAX_DEC_LEN)
177	return 0;	212	return 0;
178		213
179	int elen = encode_len (len);	214	int elen = encode_len (len);
…		…
198	*dst++ = cmap.encode [dst_ [i]];	233	*dst++ = cmap.encode [dst_ [i]];
199		234
200	return elen;	235	return elen;
201	}	236	}
202		237
		238	unsigned int
203	unsigned int basecoder::decode (u8 dst, char src, unsigned int len)	239	basecoder::decode (u8 dst, char src, unsigned int len) const
204	{	240	{
205	if (!len \|\| len > MAX_ENC_LEN)	241	if (!len \|\| len > MAX_ENC_LEN)
206	return 0;	242	return 0;
207		243
208	u8 src_ [MAX_ENC_LEN];	244	u8 src_ [MAX_ENC_LEN];
…		…
257	}	293	}
258	abort ();	294	abort ();
259	}	295	}
260	#endif	296	#endif
261		297
262	//static basecoder cdc64 ("_dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI-");
263	//static basecoder cdc63 ("_dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI");
264	static basecoder cdc62 ("dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI");	298	static basecoder cdc62 ("dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI"); // a-zA-Z0-9
265	//static basecoder cdc36 ("dphzr06qmjkb34tsvl81xaef92wgyo57ucni"); // unused as of yet	299	static basecoder cdc36 ("dPhZr06QmJkB34tSvL81xAeF92wGyO57uCnI"); // a-z0-9 for case-changers
266	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");	300	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyOuCnI"); // a-z
267		301
268	/////////////////////////////////////////////////////////////////////////////	302	/////////////////////////////////////////////////////////////////////////////
269		303
270	#define HDRSIZE 6	304	#define HDRSIZE 5
271		305
		306	inline void
272	inline void encode_header (char *data, int clientid, int seqno, int retry = 0)	307	encode_header (char *data, int clientid, int seqno, int retry = 0)
273	{	308	{
		309	assert (clientid < 256);
		310
274	seqno &= SEQNO_MASK;	311	seqno &= SEQNO_MASK;
275		312
276	u8 hdr[3] = {	313	u8 hdr[3] = {
		314	seqno,
		315	(seqno >> 8) \| (retry << 6),
277	clientid,	316	clientid,
278	(seqno >> 8) \| (retry << 6),
279	seqno,
280	};	317	};
281		318
282	assert (clientid < 256);
283
284	cdc26.encode (data, hdr, 3);	319	cdc36.encode (data, hdr, 3);
285	}	320	}
286		321
		322	inline void
287	inline void decode_header (char *data, int &clientid, int &seqno)	323	decode_header (char *data, int &clientid, int &seqno)
288	{	324	{
289	u8 hdr[3];	325	u8 hdr[3];
290		326
291	cdc26.decode (hdr, data, HDRSIZE);	327	cdc36.decode (hdr, data, HDRSIZE);
292		328
293	clientid = hdr[0];	329	clientid = hdr[2];
294	seqno = ((hdr[1] << 8) \| hdr[2]) & SEQNO_MASK;	330	seqno = ((hdr[1] << 8) \| hdr[0]) & SEQNO_MASK;
295	}	331	}
296		332
297	/////////////////////////////////////////////////////////////////////////////	333	/////////////////////////////////////////////////////////////////////////////
298		334
299	struct byte_stream	335	struct byte_stream
…		…
325	byte_stream::~byte_stream ()	361	byte_stream::~byte_stream ()
326	{	362	{
327	delete data;	363	delete data;
328	}	364	}
329		365
		366	void
330	void byte_stream::remove (int count)	367	byte_stream::remove (int count)
331	{	368	{
332	if (count > fill)	369	if (count > fill)
333	assert (count <= fill);	370	assert (count <= fill);
334		371
335	memmove (data, data + count, fill -= count);	372	memmove (data, data + count, fill -= count);
336	}	373	}
337		374
		375	bool
338	bool byte_stream::put (u8 *data, unsigned int datalen)	376	byte_stream::put (u8 *data, unsigned int datalen)
339	{	377	{
340	if (maxsize - fill < datalen)	378	if (maxsize - fill < datalen)
341	return false;	379	return false;
342		380
343	memcpy (this->data + fill, data, datalen); fill += datalen;	381	memcpy (this->data + fill, data, datalen); fill += datalen;
344		382
345	return true;	383	return true;
346	}	384	}
347		385
		386	bool
348	bool byte_stream::put (vpn_packet *pkt)	387	byte_stream::put (vpn_packet *pkt)
349	{	388	{
350	if (maxsize - fill < pkt->len + 2)	389	if (maxsize - fill < pkt->len + 2)
351	return false;	390	return false;
352		391
353	data [fill++] = pkt->len >> 8;	392	data [fill++] = pkt->len >> 8;
…		…
409		448
410	struct dns_cfg	449	struct dns_cfg
411	{	450	{
412	static int next_uid;	451	static int next_uid;
413		452
414	u8 id1, id2, id3, id4;	453	u8 chksum;
		454	u8 rrtype;
		455	u16 uid; // to make request unique
415		456
416	u8 version;	457	u8 version;
417	u8 flags;	458	u8 flags;
418	u8 rrtype;	459	u16 max_size;
		460
		461	u8 id1, id2, id3, id4;
		462
		463	u16 client;
419	u8 def_ttl;	464	u8 def_ttl;
		465	u8 r0;
420		466
421	u16 client;	467	u8 syn_cdc; // cdc en/decoder for syn (A?) requests
422	u16 uid; // to make request unique	468	u8 hdr_cdc; // cdc en/decoder for regular request headers
		469	u8 req_cdc; // cdc en/decoder for regular (ANY?) request data
		470	u8 rep_cdc; // cdc en/decoder for regular (TXT) replies, 0 == 8 bit encoding
423		471
424	u16 max_size;
425	u8 seq_cdc;
426	u8 req_cdc;
427
428	u8 rep_cdc;
429	u8 delay; // time in 0.01s units that the server may delay replying packets
430	u8 r3, r4;
431
432	u8 r5, r6, r7, r8;	472	u8 r1, r2, r3, r4;
433		473
434	void reset (int clientid);	474	void reset (int clientid);
435	bool valid ();	475	bool valid ();
		476	u8 get_chksum ();
436	};	477	};
437		478
438	int dns_cfg::next_uid;	479	int dns_cfg::next_uid;
439		480
		481	void
440	void dns_cfg::reset (int clientid)	482	dns_cfg::reset (int clientid)
441	{	483	{
		484	// this ID must result in some mixed-case characters in cdc26-encoding
442	id1 = 'G';	485	id1 = 'G';
443	id2 = 'V';	486	id2 = 'V';
444	id3 = 'P';	487	id3 = 'P';
445	id4 = 'E';	488	id4 = 'E';
446		489
447	version = 1;	490	version = 2;
448		491
449	rrtype = RR_TYPE_TXT;	492	rrtype = RR_TYPE_TXT;
450	flags = 0;	493	flags = 0;
451	def_ttl = 0;	494	def_ttl = 0;
452	seq_cdc = 26;	495	syn_cdc = 26;
453	req_cdc = 62;	496	hdr_cdc = 36;
		497	req_cdc = conf.dns_case_preserving ? 62 : 36;
454	rep_cdc = 0;	498	rep_cdc = 0;
455	max_size = htons (MAX_PKT_SIZE);	499	max_size = htons (MAX_PKT_SIZE);
456	client = htons (clientid);	500	client = htons (clientid);
457	uid = next_uid++;	501	uid = ++next_uid;
458	delay = 0;
459		502
460	r3 = r4 = 0;	503	r0 = r1 = r2 = r3 = r4 = 0;
461	r4 = r5 = r6 = r7 = 0;
462	}
463		504
		505	chksum = get_chksum ();
		506	}
		507
		508	// simple but not trivial chksum
		509	u8
		510	dns_cfg::get_chksum ()
		511	{
		512	unsigned int sum = 0xff00; // only 16 bits required
		513
		514	u8 old_chksum = chksum;
		515	chksum = 0;
		516
		517	for (unsigned int i = 0; i < sizeof (*this); ++i)
		518	sum += ((u8 )this)[i] (i + 1);
		519
		520	chksum = old_chksum;
		521
		522	return sum + (sum >> 8);
		523	}
		524
		525	bool
464	bool dns_cfg::valid ()	526	dns_cfg::valid ()
465	{	527	{
466	// although the protocol itself allows for some configurability,	528	// although the protocol itself allows for some configurability,
467	// only the following encoding/decoding settings are implemented.	529	// only the following encoding/decoding settings are implemented.
468	return id1 == 'G'	530	return id1 == 'G'
469	&& id2 == 'V'	531	&& id2 == 'V'
470	&& id3 == 'P'	532	&& id3 == 'P'
471	&& id4 == 'E'	533	&& id4 == 'E'
		534	&& version == 2
472	&& seq_cdc == 26	535	&& syn_cdc == 26
473	&& req_cdc == 62	536	&& hdr_cdc == 36
		537	&& (req_cdc == 36 \|\| req_cdc == 62)
474	&& rep_cdc == 0	538	&& rep_cdc == 0
475	&& version == 1;	539	&& chksum == get_chksum ();
476	}	540	}
477		541
478	struct dns_packet : net_packet	542	struct dns_packet : net_packet
479	{	543	{
480	u16 id;	544	u16 id;
…		…
484	u8 data [MAXSIZE - 6 * 2];	548	u8 data [MAXSIZE - 6 * 2];
485		549
486	int decode_label (char *data, int size, int &offs);	550	int decode_label (char *data, int size, int &offs);
487	};	551	};
488		552
		553	int
489	int dns_packet::decode_label (char *data, int size, int &offs)	554	dns_packet::decode_label (char *data, int size, int &offs)
490	{	555	{
491	char *orig = data;	556	char *orig = data;
492		557
493	memset (data, 0, size);	558	memset (data, 0, size);
494		559
…		…
520	return data - orig;	585	return data - orig;
521	}	586	}
522		587
523	/////////////////////////////////////////////////////////////////////////////	588	/////////////////////////////////////////////////////////////////////////////
524		589
		590	static
		591	u16 next_id ()
		592	{
525	static u16 dns_id = 0; // TODO: should be per-vpn	593	static u16 dns_id = 0; // TODO: should be per-vpn
526		594
527	static u16 next_id ()
528	{
529	if (!dns_id)	595	if (!dns_id)
530	dns_id = time (0);	596	dns_id = time (0);
531		597
532	// the simplest lsfr with periodicity 65535 i could find	598	// the simplest lsfr with periodicity 65535 i could find
533	dns_id = (dns_id << 1)	599	dns_id = (dns_id << 1)
…		…
548	struct vpn *vpn;	614	struct vpn *vpn;
549		615
550	dns_cfg cfg;	616	dns_cfg cfg;
551		617
552	bool established;	618	bool established;
		619	const basecoder *cdc;
553		620
554	tstamp last_received;	621	tstamp last_received;
555	tstamp last_sent;	622	tstamp last_sent;
556	double min_latency;	623	double min_latency;
557	double poll_interval, send_interval;	624	double poll_interval, send_interval;
…		…
559	vector<dns_rcv *> rcvpq;	626	vector<dns_rcv *> rcvpq;
560		627
561	byte_stream rcvdq; int rcvseq; int repseq;	628	byte_stream rcvdq; int rcvseq; int repseq;
562	byte_stream snddq; int sndseq;	629	byte_stream snddq; int sndseq;
563		630
564	void time_cb (time_watcher &w); time_watcher tw;	631	inline void time_cb (ev::timer &w, int revents); ev::timer tw;
565	void receive_rep (dns_rcv *r);	632	void receive_rep (dns_rcv *r);
		633
		634	void reset (); // quite like tcp RST
		635	void set_cfg (); // to be called after any cfg changes
566		636
567	dns_connection (connection *c);	637	dns_connection (connection *c);
568	~dns_connection ();	638	~dns_connection ();
569	};	639	};
570		640
…		…
588	: dns (dns)	658	: dns (dns)
589	{	659	{
590	timeout = 0;	660	timeout = 0;
591	retry = 0;	661	retry = 0;
592	seqno = 0;	662	seqno = 0;
593	sent = NOW;	663	sent = ev_now ();
594	stdhdr = false;	664	stdhdr = false;
595		665
596	pkt = new dns_packet;	666	pkt = new dns_packet;
597		667
598	pkt->id = next_id ();	668	pkt->id = next_id ();
…		…
601	dns_snd::~dns_snd ()	671	dns_snd::~dns_snd ()
602	{	672	{
603	delete pkt;	673	delete pkt;
604	}	674	}
605		675
		676	static void
606	static void append_domain (dns_packet &pkt, int &offs, const char *domain)	677	append_domain (dns_packet &pkt, int &offs, const char *domain)
607	{	678	{
608	// add tunnel domain	679	// add tunnel domain
609	for (;;)	680	for (;;)
610	{	681	{
611	const char *end = strchr (domain, '.');	682	const char *end = strchr (domain, '.');
…		…
624		695
625	domain = end + 1;	696	domain = end + 1;
626	}	697	}
627	}	698	}
628		699
		700	void
629	void dns_snd::gen_stream_req (int seqno, byte_stream &stream)	701	dns_snd::gen_stream_req (int seqno, byte_stream &stream)
630	{	702	{
631	stdhdr = true;	703	stdhdr = true;
632	this->seqno = seqno;	704	this->seqno = seqno;
633		705
634	timeout = NOW + INITIAL_TIMEOUT;	706	timeout = ev_now () + INITIAL_TIMEOUT;
635		707
636	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	708	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
637	pkt->qdcount = htons (1);	709	pkt->qdcount = htons (1);
638		710
639	int offs = 6*2;	711	int offs = 6*2;
…		…
642	// so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra	714	// so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra
643		715
644	char enc[256], *encp = enc;	716	char enc[256], *encp = enc;
645	encode_header (enc, THISNODE->id, seqno);	717	encode_header (enc, THISNODE->id, seqno);
646		718
647	int datalen = cdc62.decode_len (dlen - (dlen + MAX_LBL_SIZE - 1) / MAX_LBL_SIZE - HDRSIZE);	719	int datalen = dns->cdc->decode_len (dlen - (dlen + MAX_LBL_SIZE - 1) / MAX_LBL_SIZE - HDRSIZE);
648		720
649	if (datalen > stream.size ())	721	if (datalen > stream.size ())
650	datalen = stream.size ();	722	datalen = stream.size ();
651		723
652	int enclen = cdc62.encode (enc + HDRSIZE, stream.begin (), datalen) + HDRSIZE;	724	int enclen = dns->cdc->encode (enc + HDRSIZE, stream.begin (), datalen) + HDRSIZE;
653	stream.remove (datalen);	725	stream.remove (datalen);
654		726
655	while (enclen)	727	while (enclen)
656	{	728	{
657	int lbllen = enclen < MAX_LBL_SIZE ? enclen : MAX_LBL_SIZE;	729	int lbllen = enclen < MAX_LBL_SIZE ? enclen : MAX_LBL_SIZE;
…		…
672	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;	744	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
673		745
674	pkt->len = offs;	746	pkt->len = offs;
675	}	747	}
676		748
		749	void
677	void dns_snd::gen_syn_req ()	750	dns_snd::gen_syn_req ()
678	{	751	{
679	timeout = NOW + INITIAL_SYN_TIMEOUT;	752	timeout = ev_now () + INITIAL_SYN_TIMEOUT;
680		753
681	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	754	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
682	pkt->qdcount = htons (1);	755	pkt->qdcount = htons (1);
683		756
684	int offs = 6 * 2;	757	int offs = 6 * 2;
…		…
724		797
725	dns_connection::dns_connection (connection *c)	798	dns_connection::dns_connection (connection *c)
726	: c (c)	799	: c (c)
727	, rcvdq (MAX_BACKLOG * 2)	800	, rcvdq (MAX_BACKLOG * 2)
728	, snddq (MAX_BACKLOG)	801	, snddq (MAX_BACKLOG)
729	, tw (this, &dns_connection::time_cb)
730	{	802	{
		803	tw.set<dns_connection, &dns_connection::time_cb> (this);
		804
731	vpn = c->vpn;	805	vpn = c->vpn;
		806
		807	reset ();
		808	}
		809
		810	dns_connection::~dns_connection ()
		811	{
		812	reset ();
		813	}
		814
		815	void
		816	dns_connection::reset ()
		817	{
		818	while (!rcvpq.empty ())
		819	{
		820	delete rcvpq.back ();
		821	rcvpq.pop_back ();
		822	}
		823
		824	for (int i = vpn->dns_sndpq.size (); i--; )
		825	if (vpn->dns_sndpq [i]->dns == this)
		826	{
		827	vpn->dns_sndpq [i] = vpn->dns_sndpq.back ();
		828	vpn->dns_sndpq.pop_back ();
		829	}
732		830
733	established = false;	831	established = false;
734		832
735	rcvseq = repseq = sndseq = 0;	833	rcvseq = repseq = sndseq = 0;
736		834
…		…
738	poll_interval = 0.5; // starting here	836	poll_interval = 0.5; // starting here
739	send_interval = 0.5; // starting rate	837	send_interval = 0.5; // starting rate
740	min_latency = INITIAL_TIMEOUT;	838	min_latency = INITIAL_TIMEOUT;
741	}	839	}
742		840
743	dns_connection::~dns_connection ()	841	void
		842	dns_connection::set_cfg ()
744	{	843	{
745	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();	844	cdc = cfg.req_cdc == 36 ? &cdc36 : &cdc62;
746	i != rcvpq.end ();
747	++i)
748	delete *i;
749	}	845	}
750		846
		847	void
751	void dns_connection::receive_rep (dns_rcv *r)	848	dns_connection::receive_rep (dns_rcv *r)
752	{	849	{
753	if (r->datalen)	850	if (r->datalen)
754	{	851	{
755	last_received = NOW;	852	last_received = ev_now ();
756	tw.trigger ();	853	tw ();
757		854
758	poll_interval = send_interval;	855	poll_interval = send_interval;
759	}	856	}
760	else	857	else
761	{	858	{
…		…
771		868
772	// find next packet	869	// find next packet
773	for (vector<dns_rcv *>::iterator i = rcvpq.end (); i-- != rcvpq.begin (); )	870	for (vector<dns_rcv *>::iterator i = rcvpq.end (); i-- != rcvpq.begin (); )
774	if (SEQNO_EQ (rcvseq, (*i)->seqno))	871	if (SEQNO_EQ (rcvseq, (*i)->seqno))
775	{	872	{
		873	//printf ("seqno eq %x %x\n", rcvseq, (*i)->seqno);//D
776	// enter the packet into our input stream	874	// enter the packet into our input stream
777	r = *i;	875	r = *i;
778		876
779	// remove the oldest packet, look forward, as it's oldest first	877	// remove the oldest packet, look forward, as it's oldest first
780	for (vector<dns_rcv *>::iterator j = rcvpq.begin (); j != rcvpq.end (); ++j)	878	for (vector<dns_rcv *>::iterator j = rcvpq.begin (); j != rcvpq.end (); ++j)
781	if (SEQNO_EQ ((*j)->seqno, rcvseq - MAX_WINDOW))	879	if (SEQNO_EQ ((*j)->seqno, rcvseq - MAX_WINDOW))
782	{	880	{
		881	//printf ("seqno RR %x %x\n", (*j)->seqno, rcvseq - MAX_WINDOW);//D
783	delete *j;	882	delete *j;
784	rcvpq.erase (j);	883	rcvpq.erase (j);
785	break;	884	break;
786	}	885	}
787		886
788	rcvseq = (rcvseq + 1) & SEQNO_MASK;	887	rcvseq = (rcvseq + 1) & SEQNO_MASK;
789		888
790	if (!rcvdq.put (r->data, r->datalen))	889	if (!rcvdq.put (r->data, r->datalen))
791	{	890	{
		891	// MUST never overflow, can be caused by data corruption, TODO
792	slog (L_ERR, "DNS: !rcvdq.put (r->data, r->datalen)");	892	slog (L_CRIT, "DNS: !rcvdq.put (r->data, r->datalen)");
793	abort (); // MUST never overflow, can be caused by data corruption, TODO	893	reset ();
		894	return;
794	}	895	}
795		896
796	while (vpn_packet *pkt = rcvdq.get ())	897	while (vpn_packet *pkt = rcvdq.get ())
797	{	898	{
798	sockinfo si;	899	sockinfo si;
799	si.host = htonl (c->conf->id); si.port = 0; si.prot = PROT_DNSv4;	900	si.host = htonl (c->conf->id); si.port = 0; si.prot = PROT_DNSv4;
800		901
801	vpn->recv_vpn_packet (pkt, si);	902	vpn->recv_vpn_packet (pkt, si);
802
803	delete pkt;	903	delete pkt;
804	}	904	}
805		905
806	// check for further packets	906	// check for further packets
807	goto redo;	907	goto redo;
…		…
850	{	950	{
851	// correct class, domain: parse	951	// correct class, domain: parse
852	int client, seqno;	952	int client, seqno;
853	decode_header (qname, client, seqno);	953	decode_header (qname, client, seqno);
854		954
855	u8 data[MAXSIZE];
856	int datalen = cdc62.decode (data, qname + HDRSIZE, qlen - (dlen + 1 + HDRSIZE));
857
858	if (0 < client && client <= conns.size ())	955	if (0 < client && client <= conns.size ())
859	{	956	{
860	connection *c = conns [client - 1];	957	connection *c = conns [client - 1];
861	dns_connection *dns = c->dns;	958	dns_connection *dns = c->dns;
862	dns_rcv *rcv;	959	dns_rcv *rcv;
863		960
864	if (dns)	961	if (dns)
865	{	962	{
		963	u8 data[MAXSIZE];
		964	int datalen = dns->cdc->decode (data, qname + HDRSIZE, qlen - (dlen + 1 + HDRSIZE));
		965
866	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )	966	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )
867	if (SEQNO_EQ ((*i)->seqno, seqno))	967	if (SEQNO_EQ ((*i)->seqno, seqno))
868	{	968	{
869	// already seen that request: simply reply with the cached reply	969	// already seen that request: simply reply with the cached reply
870	dns_rcv r = i;	970	dns_rcv r = i;
…		…
971	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class	1071	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
972	pkt [offs++] = 0; pkt [offs++] = 0;	1072	pkt [offs++] = 0; pkt [offs++] = 0;
973	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL	1073	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL
974	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength	1074	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength
975		1075
976	slog (L_INFO, _("DNS: client %d connects"), client);
977
978	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;	1076	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
979	pkt [offs++] = CMD_IP_REJ;	1077	pkt [offs++] = CMD_IP_REJ;
980		1078
981	if (0 < client && client <= conns.size ())	1079	if (0 < client && client <= conns.size ())
982	{	1080	{
983	connection *c = conns [client - 1];	1081	connection *c = conns [client - 1];
984		1082
985	if (cfg.valid ())	1083	if (cfg.valid ())
986	{	1084	{
987	pkt [offs - 1] = CMD_IP_SYN;	1085	slog (L_INFO, _("DNS: client %d connects (version %d, req_cdc %d)"), client, cfg.version, cfg.req_cdc);
		1086
		1087	// check for any encoding mismatches - hints at a case problem
		1088	char qname2 [MAX_ENC_LEN];
		1089	cdc26.encode (qname2, (u8 *)&cfg, sizeof (dns_cfg));
988		1090
989	delete c->dns;	1091	delete c->dns;
		1092
		1093	pkt [offs - 1] = memcmp (qname, qname2, cdc26.encode_len (sizeof (dns_cfg)))
		1094	? CMD_IP_CSE : CMD_IP_SYN;
		1095
990	c->dns = new dns_connection (c);	1096	c->dns = new dns_connection (c);
991	c->dns->cfg = cfg;	1097	c->dns->cfg = cfg;
		1098	c->dns->set_cfg ();
992	}	1099	}
993	}	1100	}
994	}	1101	}
995	}	1102	}
996		1103
…		…
1015	{	1122	{
1016	dns_connection dns = (i)->dns;	1123	dns_connection dns = (i)->dns;
1017	connection *c = dns->c;	1124	connection *c = dns->c;
1018	int seqno = (*i)->seqno;	1125	int seqno = (*i)->seqno;
1019	u8 data[MAXSIZE], *datap = data;	1126	u8 data[MAXSIZE], *datap = data;
		1127	//printf ("rcv pkt %x\n", seqno);//D
		1128	bool back_off = (*i)->retry;
1020		1129
1021	if ((*i)->retry)	1130	if (back_off)
1022	{	1131	{
1023	dns->send_interval *= 1.01;	1132	dns->send_interval *= 1.01;
1024	if (dns->send_interval > MAX_SEND_INTERVAL)	1133	if (dns->send_interval > MAX_SEND_INTERVAL)
1025	dns->send_interval = MAX_SEND_INTERVAL;	1134	dns->send_interval = MAX_SEND_INTERVAL;
1026	}	1135	}
…		…
1029	#if 0	1138	#if 0
1030	dns->send_interval *= 0.999;	1139	dns->send_interval *= 0.999;
1031	#endif	1140	#endif
1032	// the latency surely puts an upper bound on	1141	// the latency surely puts an upper bound on
1033	// the minimum send interval	1142	// the minimum send interval
1034	double latency = NOW - (*i)->sent;	1143	double latency = ev_now () - (*i)->sent;
1035		1144
1036	if (latency < dns->min_latency)	1145	if (latency < dns->min_latency)
1037	dns->min_latency = latency;	1146	dns->min_latency = latency;
1038		1147
1039	if (dns->send_interval > dns->min_latency * conf.dns_overlap_factor)	1148	if (dns->send_interval > dns->min_latency * conf.dns_overlap_factor)
…		…
1066	ttl \|= pkt [offs++] << 16;	1175	ttl \|= pkt [offs++] << 16;
1067	ttl \|= pkt [offs++] << 8;	1176	ttl \|= pkt [offs++] << 8;
1068	ttl \|= pkt [offs++];	1177	ttl \|= pkt [offs++];
1069	u16 rdlen = pkt [offs++] << 8; rdlen \|= pkt [offs++];	1178	u16 rdlen = pkt [offs++] << 8; rdlen \|= pkt [offs++];
1070		1179
1071	if (qtype == RR_TYPE_NULL \|\| qtype == RR_TYPE_TXT)	1180	if (qtype == RR_TYPE_NULL \|\| qtype == RR_TYPE_TXT \|\| qtype == dns->cfg.rrtype)
1072	{	1181	{
1073	if (rdlen <= MAXSIZE - offs)	1182	if (rdlen <= MAXSIZE - offs)
1074	{	1183	{
1075	// decode bytes, finally	1184	// decode bytes, finally
1076		1185
…		…
1102	{	1211	{
1103	slog (L_TRACE, _("DNS: got tunnel meta command %02x"), ip [3]);	1212	slog (L_TRACE, _("DNS: got tunnel meta command %02x"), ip [3]);
1104		1213
1105	if (ip [3] == CMD_IP_RST)	1214	if (ip [3] == CMD_IP_RST)
1106	{	1215	{
1107	slog (L_DEBUG, _("DNS: got tunnel RST request"));	1216	slog (L_DEBUG, _("DNS: got tunnel RST request."));
1108		1217
1109	delete dns; c->dns = 0;	1218	dns->reset ();
1110
1111	return;	1219	return;
1112	}	1220	}
1113	else if (ip [3] == CMD_IP_SYN)	1221	else if (ip [3] == CMD_IP_SYN)
1114	{	1222	{
1115	slog (L_DEBUG, _("DNS: got tunnel SYN reply, server likes us."));	1223	slog (L_DEBUG, _("DNS: got tunnel SYN reply, server likes us."));
1116	dns->established = true;	1224	dns->established = true;
1117	}	1225	}
		1226	else if (ip [3] == CMD_IP_CSE)
		1227	{
		1228	if (conf.dns_case_preserving)
		1229	{
		1230	slog (L_INFO, _("DNS: got tunnel CSE reply, globally downgrading to case-insensitive protocol."));
		1231	conf.dns_case_preserving = false;
		1232	dns->reset ();
		1233	return;
		1234	}
		1235	else
		1236	{
		1237	slog (L_DEBUG, _("DNS: got tunnel CSE reply, server likes us."));
		1238	dns->established = true;
		1239	}
		1240	}
1118	else if (ip [3] == CMD_IP_REJ)	1241	else if (ip [3] == CMD_IP_REJ)
1119	{	1242	{
1120	slog (L_DEBUG, _("DNS: got tunnel REJ reply, server does not like us, aborting."));	1243	slog (L_ERR, _("DNS: got tunnel REJ reply, server does not like us."));
1121	abort ();	1244	dns->tw.start (60.);
1122	}	1245	}
1123	else	1246	else
		1247	{
1124	slog (L_INFO, _("DNS: got unknown meta command %02x"), ip [3]);	1248	slog (L_INFO, _("DNS: got unknown meta command %02x"), ip [3]);
		1249	dns->tw.start (60.);
		1250	}
1125	}	1251	}
1126	else	1252	else
1127	slog (L_INFO, _("DNS: got spurious a record %d.%d.%d.%d"),	1253	slog (L_INFO, _("DNS: got spurious a record %d.%d.%d.%d"),
1128	ip [0], ip [1], ip [2], ip [3]);	1254	ip [0], ip [1], ip [2], ip [3]);
1129		1255
…		…
1147	}	1273	}
1148		1274
1149	// todo: pkt now used	1275	// todo: pkt now used
1150	if (datap)	1276	if (datap)
1151	dns->receive_rep (new dns_rcv (seqno, data, datap - data));	1277	dns->receive_rep (new dns_rcv (seqno, data, datap - data));
		1278	else if (dns_sndpq.empty ()) // no data received, and nothing to send - idle
		1279	{
		1280	dns->send_interval *= 1.1;
		1281
		1282	if (dns->send_interval < MIN_POLL_INTERVAL)
		1283	dns->send_interval = MIN_POLL_INTERVAL;
		1284
		1285	if (dns->send_interval > MAX_POLL_INTERVAL && !back_off)
		1286	dns->send_interval = MAX_POLL_INTERVAL;
		1287	}
1152		1288
1153	break;	1289	break;
1154	}	1290	}
1155	}	1291	}
1156		1292
1157	void	1293	void
1158	vpn::dnsv4_ev (io_watcher &w, short revents)	1294	vpn::dnsv4_ev (ev::io &w, int revents)
1159	{	1295	{
1160	if (revents & EVENT_READ)	1296	if (revents & EV_READ)
1161	{	1297	{
1162	dns_packet *pkt = new dns_packet;	1298	dns_packet *pkt = new dns_packet;
1163	struct sockaddr_in sa;	1299	struct sockaddr_in sa;
1164	socklen_t sa_len = sizeof (sa);	1300	socklen_t sa_len = sizeof (sa);
1165		1301
…		…
1191		1327
1192	if (!c->dns)	1328	if (!c->dns)
1193	c->dns = new dns_connection (c);	1329	c->dns = new dns_connection (c);
1194		1330
1195	if (c->dns->snddq.put (pkt))	1331	if (c->dns->snddq.put (pkt))
1196	c->dns->tw.trigger ();	1332	c->dns->tw ();
1197		1333
1198	// always return true even if the buffer overflows	1334	// always return true even if the buffer overflows
1199	return true;	1335	return true;
1200	}	1336	}
1201		1337
		1338	#define NEXT(w) do { if (next > (w)) next = w; } while (0)
		1339
1202	void	1340	void
1203	connection::dnsv4_reset_connection ()	1341	dns_connection::time_cb (ev::timer &w, int revents)
1204	{
1205	//delete dns; dns = 0; //TODO
1206	}
1207
1208	#define NEXT(w) do { if (next > (w)) next = w; } while (0)
1209
1210	void
1211	dns_connection::time_cb (time_watcher &w)
1212	{	1342	{
1213	// servers have to be polled	1343	// servers have to be polled
1214	if (THISNODE->dns_port)	1344	if (THISNODE->dns_port)
1215	return;	1345	return;
1216		1346
1217	// check for timeouts and (re)transmit	1347	// check for timeouts and (re)transmit
1218	tstamp next = NOW + poll_interval;	1348	tstamp next = ev::now () + poll_interval;
1219	dns_snd *send = 0;	1349	dns_snd *send = 0;
1220		1350
1221	for (vector<dns_snd *>::iterator i = vpn->dns_sndpq.begin ();	1351	for (vector<dns_snd *>::iterator i = vpn->dns_sndpq.begin ();
1222	i != vpn->dns_sndpq.end ();	1352	i != vpn->dns_sndpq.end ();
1223	++i)	1353	++i)
1224	{	1354	{
1225	dns_snd r = i;	1355	dns_snd r = i;
1226		1356
1227	if (r->timeout <= NOW)	1357	if (r->timeout <= ev_now ())
1228	{	1358	{
1229	if (!send)	1359	if (!send)
1230	{	1360	{
1231	send = r;	1361	send = r;
1232		1362
1233	r->retry++;	1363	r->retry++;
1234	r->timeout = NOW + (r->retry * min_latency * conf.dns_timeout_factor);	1364	r->timeout = ev_now () + (r->retry * min_latency * conf.dns_timeout_factor);
		1365	//printf ("RETRY %x (%d, %f)\n", r->seqno, r->retry, r->timeout - ev_now ());//D
1235		1366
1236	// the following code changes the query section a bit, forcing	1367	// the following code changes the query section a bit, forcing
1237	// the forwarder to generate a new request	1368	// the forwarder to generate a new request
1238	if (r->stdhdr)	1369	if (r->stdhdr)
1239	{
1240	//printf ("reencoded header for ID %d retry %d:%d:%d (%p)\n", htons (r->pkt->id), THISNODE->id, r->seqno, r->retry);
1241	//encode_header ((char )r->pkt->at (6 2 + 1), THISNODE->id, r->seqno, r->retry);	1370	encode_header ((char )r->pkt->at (6 2 + 1), THISNODE->id, r->seqno, r->retry);
1242	}
1243	}	1371	}
1244	}	1372	}
1245	else	1373	else
1246	NEXT (r->timeout);	1374	NEXT (r->timeout);
1247	}	1375	}
…		…
1255	if (vpn->dns_sndpq.empty ())	1383	if (vpn->dns_sndpq.empty ())
1256	{	1384	{
1257	send = new dns_snd (this);	1385	send = new dns_snd (this);
1258		1386
1259	cfg.reset (THISNODE->id);	1387	cfg.reset (THISNODE->id);
		1388	set_cfg ();
1260	send->gen_syn_req ();	1389	send->gen_syn_req ();
1261	}	1390	}
1262	}	1391	}
1263	else if (vpn->dns_sndpq.size () < conf.dns_max_outstanding	1392	else if (vpn->dns_sndpq.size () < conf.dns_max_outstanding
1264	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))	1393	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
1265	{	1394	{
1266	if (last_sent + send_interval <= NOW)	1395	if (last_sent + send_interval <= ev_now ())
1267	{	1396	{
1268	//printf ("sending data request etc.\n"); //D	1397	//printf ("sending data request etc.\n"); //D
1269	if (!snddq.empty () \|\| last_received + 1. > NOW)	1398	if (!snddq.empty () \|\| last_received + 1. > ev_now ())
1270	{	1399	{
1271	poll_interval = send_interval;	1400	poll_interval = send_interval;
1272	NEXT (NOW + send_interval);	1401	NEXT (ev_now () + send_interval);
1273	}	1402	}
1274		1403
1275	send = new dns_snd (this);	1404	send = new dns_snd (this);
1276	send->gen_stream_req (sndseq, snddq);	1405	send->gen_stream_req (sndseq, snddq);
1277	send->timeout = NOW + min_latency * conf.dns_timeout_factor;	1406	send->timeout = ev_now () + min_latency * conf.dns_timeout_factor;
		1407	//printf ("SEND %x (%f)\n", send->seqno, send->timeout - ev_now (), min_latency, conf.dns_timeout_factor);//D
1278		1408
1279	sndseq = (sndseq + 1) & SEQNO_MASK;	1409	sndseq = (sndseq + 1) & SEQNO_MASK;
1280	}	1410	}
1281	else	1411	else
1282	NEXT (last_sent + send_interval);	1412	NEXT (last_sent + send_interval);
…		…
1286	vpn->dns_sndpq.push_back (send);	1416	vpn->dns_sndpq.push_back (send);
1287	}	1417	}
1288		1418
1289	if (send)	1419	if (send)
1290	{	1420	{
1291	last_sent = NOW;	1421	last_sent = ev_now ();
1292	sendto (vpn->dnsv4_fd,	1422	sendto (vpn->dnsv4_fd,
1293	send->pkt->at (0), send->pkt->len, 0,	1423	send->pkt->at (0), send->pkt->len, 0,
1294	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());	1424	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
1295	}	1425	}
1296		1426
1297	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",	1427	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",
1298	poll_interval, send_interval, next - NOW,	1428	poll_interval, send_interval, next - ev_now (),
1299	vpn->dns_sndpq.size (), snddq.size (),	1429	vpn->dns_sndpq.size (), snddq.size (),
1300	rcvpq.size ());	1430	rcvpq.size ());
1301		1431
1302	// TODO: no idea when this happens, but when next < NOW, we have a problem	1432	// TODO: no idea when this happens, but when next < ev_now (), we have a problem
1303	// doesn't seem to happen anymore	1433	// doesn't seem to happen anymore
1304	if (next < NOW + 0.001)	1434	if (next < ev_now () + 0.001)
1305	next = NOW + 0.1;	1435	next = ev_now () + 0.1;
1306		1436
1307	w.start (next);	1437	w.start (next - ev_now ());
1308	}	1438	}
1309		1439
1310	#endif	1440	#endif
1311		1441

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Comparing gvpe/src/vpn_dns.C (file contents): Revision 1.40 by pcg, Sat Jul 9 20:29:29 2005 UTC vs. Revision 1.51 by root, Sun Mar 6 19:40:28 2011 UTC

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Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.40 by pcg, Sat Jul 9 20:29:29 2005 UTC vs.
Revision 1.51 by root, Sun Mar 6 19:40:28 2011 UTC