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

Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC vs.
Revision 1.46 by pcg, Thu Dec 6 00:35:29 2007 UTC

…		…
14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15	GNU General Public License for more details.	15	GNU General 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
18	along with gvpe; if not, write to the Free Software	18	along with gvpe; if not, write to the Free Software
19	Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA	19	Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20	*/	20	*/
		21
		22	// TODO: EDNS0 option to increase dns mtu?
		23	// TODO: re-write dns packet parsing/creation using a safe mem-buffer
		24	// to ensure no buffer overflows or similar problems.
21		25
22	#include "config.h"	26	#include "config.h"
23		27
24	#if ENABLE_DNS	28	#if ENABLE_DNS
25		29
26	// dns processing is EXTREMELY ugly. For obvious(?) reasons.	30	// dns processing is EXTREMELY ugly. For obvious(?) reasons.
27	// it's a hack, use only in emergency situations please.	31	// it's a hack, use only in emergency situations please.
28		32
29	#include <cstring>	33	#include <cstring>
		34	#include <cassert>
30		35
31	#include <sys/types.h>	36	#include <sys/types.h>
32	#include <sys/socket.h>	37	#include <sys/socket.h>
33	#include <sys/wait.h>	38	#include <sys/wait.h>
34	#include <sys/uio.h>	39	#include <sys/uio.h>
…		…
37	#include <unistd.h>	42	#include <unistd.h>
38	#include <fcntl.h>	43	#include <fcntl.h>
39		44
40	#include <map>	45	#include <map>
41		46
		47	#include <cstdio> /* bug in libgmp: gmp.h relies on cstdio being included */
42	#include <gmp.h>	48	#include <gmp.h>
43		49
44	#include "netcompat.h"	50	#include "netcompat.h"
45		51
46	#include "vpn.h"	52	#include "vpn.h"
47		53
48	#define MIN_POLL_INTERVAL .02 // how often to poll minimally when the server has data
49	#define MAX_POLL_INTERVAL 6. // how often to poll minimally when the server has no data	54	#define MAX_POLL_INTERVAL 5. // how often to poll minimally when the server has no data
50	#define ACTIVITY_INTERVAL 5.	55	#define ACTIVITY_INTERVAL 5.
51		56
52	#define INITIAL_TIMEOUT 0.1 // retry timeouts	57	#define INITIAL_TIMEOUT 0.1 // retry timeouts
53	#define INITIAL_SYN_TIMEOUT 10. // retry timeout for initial syn	58	#define INITIAL_SYN_TIMEOUT 2. // retry timeout for initial syn
54		59
55	#define MIN_SEND_INTERVAL 0.01 // wait at least this time between sending requests
56	#define MAX_SEND_INTERVAL 0.5 // optimistic?	60	#define MAX_SEND_INTERVAL 2. // optimistic?
57		61
58	#define MAX_OUTSTANDING 10 // max. outstanding requests
59	#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING, and backlog	62	#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING, and backlog
60	#define MAX_BACKLOG (100*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE	63	#define MAX_BACKLOG (64*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE
61		64
62	#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well	65	#define MAX_DOMAIN_SIZE 240 // 255 is legal limit, but bind doesn't compress well
63	// 240 leaves about 4 bytes of server reply data	66	// 240 leaves about 4 bytes of server reply data
64	// every two request bytes less give room for one reply byte	67	// every request byte less give room for two reply bytes
65		68
66	#define SEQNO_MASK 0x3fff	69	#define SEQNO_MASK 0x3fff
67	#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )	70	#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )
68		71
69	#define MAX_LBL_SIZE 63	72	#define MAX_LBL_SIZE 63
…		…
264	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");	267	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");
265		268
266	/////////////////////////////////////////////////////////////////////////////	269	/////////////////////////////////////////////////////////////////////////////
267		270
268	#define HDRSIZE 6	271	#define HDRSIZE 6
269		272
270	inline void encode_header (char *data, int clientid, int seqno, int retry = 0)	273	inline void encode_header (char *data, int clientid, int seqno, int retry = 0)
271	{	274	{
272	seqno &= SEQNO_MASK;	275	seqno &= SEQNO_MASK;
273		276
274	u8 hdr[3] = {	277	u8 hdr[3] = {
…		…
408	struct dns_cfg	411	struct dns_cfg
409	{	412	{
410	static int next_uid;	413	static int next_uid;
411		414
412	u8 id1, id2, id3, id4;	415	u8 id1, id2, id3, id4;
		416
413	u8 version;	417	u8 version;
		418	u8 flags;
414	u8 rrtype;	419	u8 rrtype;
415	u8 flags;
416	u8 def_ttl;	420	u8 def_ttl;
417	u8 rcv_cdc;	421
418	u8 snd_cdc;
419	u16 max_size;
420	u16 client;	422	u16 client;
421	u16 uid; // to make request unique	423	u16 uid; // to make request unique
422		424
423	u8 reserved[8];	425	u16 max_size;
		426	u8 seq_cdc;
		427	u8 req_cdc;
		428
		429	u8 rep_cdc;
		430	u8 delay; // time in 0.01s units that the server may delay replying packets
		431	u8 r3, r4;
		432
		433	u8 r5, r6, r7, r8;
424		434
425	void reset (int clientid);	435	void reset (int clientid);
426	bool valid ();	436	bool valid ();
427	};	437	};
428		438
…		…
437		447
438	version = 1;	448	version = 1;
439		449
440	rrtype = RR_TYPE_TXT;	450	rrtype = RR_TYPE_TXT;
441	flags = 0;	451	flags = 0;
442	def_ttl = 1;	452	def_ttl = 0;
		453	seq_cdc = 26;
		454	req_cdc = 62;
443	rcv_cdc = 0;	455	rep_cdc = 0;
444	snd_cdc = 62;
445	max_size = ntohs (MAX_PKT_SIZE);	456	max_size = htons (MAX_PKT_SIZE);
446	client = ntohs (clientid);	457	client = htons (clientid);
447	uid = next_uid++;	458	uid = next_uid++;
		459	delay = 0;
448		460
449	memset (reserved, 0, 8);	461	r3 = r4 = 0;
		462	r4 = r5 = r6 = r7 = 0;
450	}	463	}
451		464
452	bool dns_cfg::valid ()	465	bool dns_cfg::valid ()
453	{	466	{
		467	// although the protocol itself allows for some configurability,
		468	// only the following encoding/decoding settings are implemented.
454	return id1 == 'G'	469	return id1 == 'G'
455	&& id2 == 'V'	470	&& id2 == 'V'
456	&& id3 == 'P'	471	&& id3 == 'P'
457	&& id4 == 'E'	472	&& id4 == 'E'
		473	&& seq_cdc == 26
		474	&& req_cdc == 62
		475	&& rep_cdc == 0
458	&& version == 1	476	&& version == 1;
459	&& flags == 0
460	&& rcv_cdc == 0
461	&& snd_cdc == 62
462	&& max_size == ntohs (MAX_PKT_SIZE);
463	}	477	}
464		478
465	struct dns_packet : net_packet	479	struct dns_packet : net_packet
466	{	480	{
467	u16 id;	481	u16 id;
468	u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4	482	u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4
469	u16 qdcount, ancount, nscount, arcount;	483	u16 qdcount, ancount, nscount, arcount;
470		484
471	u8 data[MAXSIZE - 6 * 2];	485	u8 data [MAXSIZE - 6 * 2];
472		486
473	int decode_label (char *data, int size, int &offs);	487	int decode_label (char *data, int size, int &offs);
474	};	488	};
475		489
476	int dns_packet::decode_label (char *data, int size, int &offs)	490	int dns_packet::decode_label (char *data, int size, int &offs)
…		…
538		552
539	bool established;	553	bool established;
540		554
541	tstamp last_received;	555	tstamp last_received;
542	tstamp last_sent;	556	tstamp last_sent;
543	double last_latency;	557	double min_latency;
544	double poll_interval, send_interval;	558	double poll_interval, send_interval;
545		559
546	vector<dns_rcv *> rcvpq;	560	vector<dns_rcv *> rcvpq;
547		561
548	byte_stream rcvdq; int rcvseq;	562	byte_stream rcvdq; int rcvseq; int repseq;
549	byte_stream snddq; int sndseq;	563	byte_stream snddq; int sndseq;
550		564
551	void time_cb (time_watcher &w); time_watcher tw;	565	inline void time_cb (ev::timer &w, int revents); ev::timer tw;
552	void receive_rep (dns_rcv *r);	566	void receive_rep (dns_rcv *r);
553		567
554	dns_connection (connection *c);	568	dns_connection (connection *c);
555	~dns_connection ();	569	~dns_connection ();
556	};	570	};
…		…
575	: dns (dns)	589	: dns (dns)
576	{	590	{
577	timeout = 0;	591	timeout = 0;
578	retry = 0;	592	retry = 0;
579	seqno = 0;	593	seqno = 0;
580	sent = NOW;	594	sent = ev_now ();
581	stdhdr = false;	595	stdhdr = false;
582		596
583	pkt = new dns_packet;	597	pkt = new dns_packet;
584		598
585	pkt->id = next_id ();	599	pkt->id = next_id ();
…		…
616	void dns_snd::gen_stream_req (int seqno, byte_stream &stream)	630	void dns_snd::gen_stream_req (int seqno, byte_stream &stream)
617	{	631	{
618	stdhdr = true;	632	stdhdr = true;
619	this->seqno = seqno;	633	this->seqno = seqno;
620		634
621	timeout = NOW + INITIAL_TIMEOUT;	635	timeout = ev_now () + INITIAL_TIMEOUT;
622		636
623	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	637	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
624	pkt->qdcount = htons (1);	638	pkt->qdcount = htons (1);
625		639
626	int offs = 6*2;	640	int offs = 6*2;
627	int dlen = MAX_DOMAIN_SIZE - (strlen (THISNODE->domain) + 2);	641	int dlen = MAX_DOMAIN_SIZE - (strlen (dns->c->conf->domain) + 2);
628	// MAX_DOMAIN_SIZE is technically 255, but bind doesn't compress responses well,	642	// MAX_DOMAIN_SIZE is technically 255, but bind doesn't compress responses well,
629	// so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra	643	// so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra
630		644
631	char enc[256], *encp = enc;	645	char enc[256], *encp = enc;
632	encode_header (enc, THISNODE->id, seqno);	646	encode_header (enc, THISNODE->id, seqno);
…		…
650	encp += lbllen;	664	encp += lbllen;
651		665
652	enclen -= lbllen;	666	enclen -= lbllen;
653	}	667	}
654		668
655	append_domain (*pkt, offs, THISNODE->domain);	669	append_domain (*pkt, offs, dns->c->conf->domain);
656		670
657	(*pkt)[offs++] = 0;	671	(*pkt)[offs++] = 0;
658	(pkt)[offs++] = RR_TYPE_ANY >> 8; (pkt)[offs++] = RR_TYPE_ANY;	672	(pkt)[offs++] = RR_TYPE_ANY >> 8; (pkt)[offs++] = RR_TYPE_ANY;
659	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;	673	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
660		674
661	pkt->len = offs;	675	pkt->len = offs;
662	}	676	}
663		677
664	void dns_snd::gen_syn_req ()	678	void dns_snd::gen_syn_req ()
665	{	679	{
666	timeout = NOW + INITIAL_SYN_TIMEOUT;	680	timeout = ev_now () + INITIAL_SYN_TIMEOUT;
667
668	printf ("send syn\n");//D
669		681
670	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	682	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
671	pkt->qdcount = htons (1);	683	pkt->qdcount = htons (1);
672		684
673	int offs = 6 * 2;	685	int offs = 6 * 2;
…		…
676		688
677	assert (elen <= MAX_LBL_SIZE);	689	assert (elen <= MAX_LBL_SIZE);
678		690
679	(*pkt)[offs] = elen;	691	(*pkt)[offs] = elen;
680	offs += elen + 1;	692	offs += elen + 1;
681	append_domain (*pkt, offs, THISNODE->domain);	693	append_domain (*pkt, offs, dns->c->conf->domain);
682		694
683	(*pkt)[offs++] = 0;	695	(*pkt)[offs++] = 0;
684	(pkt)[offs++] = RR_TYPE_A >> 8; (pkt)[offs++] = RR_TYPE_A;	696	(pkt)[offs++] = RR_TYPE_A >> 8; (pkt)[offs++] = RR_TYPE_A;
685	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;	697	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
686		698
…		…
712	/////////////////////////////////////////////////////////////////////////////	724	/////////////////////////////////////////////////////////////////////////////
713		725
714	dns_connection::dns_connection (connection *c)	726	dns_connection::dns_connection (connection *c)
715	: c (c)	727	: c (c)
716	, rcvdq (MAX_BACKLOG * 2)	728	, rcvdq (MAX_BACKLOG * 2)
717	, snddq (MAX_BACKLOG * 2)	729	, snddq (MAX_BACKLOG)
718	, tw (this, &dns_connection::time_cb)
719	{	730	{
		731	tw.set<dns_connection, &dns_connection::time_cb> (this);
		732
720	vpn = c->vpn;	733	vpn = c->vpn;
721		734
722	established = false;	735	established = false;
723		736
724	rcvseq = sndseq = 0;	737	rcvseq = repseq = sndseq = 0;
725		738
726	last_sent = last_received = 0;	739	last_sent = last_received = 0;
727	poll_interval = MIN_POLL_INTERVAL;	740	poll_interval = 0.5; // starting here
728	send_interval = 0.5; // starting rate	741	send_interval = 0.5; // starting rate
729	last_latency = INITIAL_TIMEOUT;	742	min_latency = INITIAL_TIMEOUT;
730	}	743	}
731		744
732	dns_connection::~dns_connection ()	745	dns_connection::~dns_connection ()
733	{	746	{
734	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();	747	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();
…		…
739		752
740	void dns_connection::receive_rep (dns_rcv *r)	753	void dns_connection::receive_rep (dns_rcv *r)
741	{	754	{
742	if (r->datalen)	755	if (r->datalen)
743	{	756	{
744	last_received = NOW;	757	last_received = ev_now ();
745	tw.trigger ();	758	tw ();
746		759
747	poll_interval = send_interval;	760	poll_interval = send_interval;
748	}	761	}
749	else	762	else
750	{	763	{
751	poll_interval *= 1.5;	764	poll_interval *= 1.5;
		765
752	if (poll_interval > MAX_POLL_INTERVAL)	766	if (poll_interval > MAX_POLL_INTERVAL)
753	poll_interval = MAX_POLL_INTERVAL;	767	poll_interval = MAX_POLL_INTERVAL;
754	}	768	}
755		769
756	rcvpq.push_back (r);	770	rcvpq.push_back (r);
…		…
759		773
760	// find next packet	774	// find next packet
761	for (vector<dns_rcv *>::iterator i = rcvpq.end (); i-- != rcvpq.begin (); )	775	for (vector<dns_rcv *>::iterator i = rcvpq.end (); i-- != rcvpq.begin (); )
762	if (SEQNO_EQ (rcvseq, (*i)->seqno))	776	if (SEQNO_EQ (rcvseq, (*i)->seqno))
763	{	777	{
		778	//printf ("seqno eq %x %x\n", rcvseq, (*i)->seqno);//D
764	// enter the packet into our input stream	779	// enter the packet into our input stream
765	r = *i;	780	r = *i;
766		781
767	// remove the oldest packet, look forward, as it's oldest first	782	// remove the oldest packet, look forward, as it's oldest first
768	for (vector<dns_rcv *>::iterator j = rcvpq.begin (); j != rcvpq.end (); ++j)	783	for (vector<dns_rcv *>::iterator j = rcvpq.begin (); j != rcvpq.end (); ++j)
769	if (SEQNO_EQ ((*j)->seqno, rcvseq - MAX_WINDOW))	784	if (SEQNO_EQ ((*j)->seqno, rcvseq - MAX_WINDOW))
770	{	785	{
		786	//printf ("seqno RR %x %x\n", (*j)->seqno, rcvseq - MAX_WINDOW);//D
771	delete *j;	787	delete *j;
772	rcvpq.erase (j);	788	rcvpq.erase (j);
773	break;	789	break;
774	}	790	}
775		791
…		…
782	}	798	}
783		799
784	while (vpn_packet *pkt = rcvdq.get ())	800	while (vpn_packet *pkt = rcvdq.get ())
785	{	801	{
786	sockinfo si;	802	sockinfo si;
787	si.host = 0x01010101; si.port = htons (c->conf->id); si.prot = PROT_DNSv4;	803	si.host = htonl (c->conf->id); si.port = 0; si.prot = PROT_DNSv4;
788		804
789	vpn->recv_vpn_packet (pkt, si);	805	vpn->recv_vpn_packet (pkt, si);
790		806
791	delete pkt;	807	delete pkt;
792	}	808	}
…		…
806	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);	822	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);
807		823
808	if (0 == (flags & (FLAG_RESPONSE \| FLAG_OP_MASK))	824	if (0 == (flags & (FLAG_RESPONSE \| FLAG_OP_MASK))
809	&& pkt.qdcount == htons (1))	825	&& pkt.qdcount == htons (1))
810	{	826	{
811	char qname[MAXSIZE];	827	char qname [MAXSIZE];
812	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);	828	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
813		829
814	u16 qtype = pkt [offs++] << 8; qtype \|= pkt [offs++];	830	u16 qtype = pkt [offs++] << 8; qtype \|= pkt [offs++];
815	u16 qclass = pkt [offs++] << 8; qclass \|= pkt [offs++];	831	u16 qclass = pkt [offs++] << 8; qclass \|= pkt [offs++];
816		832
…		…
823		839
824	int dlen = strlen (THISNODE->domain);	840	int dlen = strlen (THISNODE->domain);
825		841
826	if (qclass == RR_CLASS_IN	842	if (qclass == RR_CLASS_IN
827	&& qlen > dlen + 1	843	&& qlen > dlen + 1
828	&& !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen))	844	&& !memcmp (qname + qlen - (dlen + 1), THISNODE->domain, dlen))
829	{	845	{
830	// now generate reply	846	// now generate reply
831	pkt.ancount = htons (1); // one answer RR	847	pkt.ancount = htons (1); // one answer RR
832	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_OK);	848	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_OK);
833		849
…		…
846	if (0 < client && client <= conns.size ())	862	if (0 < client && client <= conns.size ())
847	{	863	{
848	connection *c = conns [client - 1];	864	connection *c = conns [client - 1];
849	dns_connection *dns = c->dns;	865	dns_connection *dns = c->dns;
850	dns_rcv *rcv;	866	dns_rcv *rcv;
851	bool in_seq;
852		867
853	if (dns)	868	if (dns)
854	{	869	{
855	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )	870	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )
856	if (SEQNO_EQ ((*i)->seqno, seqno))	871	if (SEQNO_EQ ((*i)->seqno, seqno))
…		…
867	memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len);	882	memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len);
868		883
869	goto duplicate_request;	884	goto duplicate_request;
870	}	885	}
871		886
872	in_seq = dns->rcvseq == seqno;
873
874	// new packet, queue	887	// new packet, queue
875	rcv = new dns_rcv (seqno, data, datalen);	888	rcv = new dns_rcv (seqno, data, datalen);
876	dns->receive_rep (rcv);	889	dns->receive_rep (rcv);
877	}	890	}
878		891
		892	{
879	pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section	893	pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section
880		894
881	int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A;	895	int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A;
882	pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type	896	pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type
883	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class	897	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
884	pkt [offs++] = 0; pkt [offs++] = 0;	898	pkt [offs++] = 0; pkt [offs++] = 0;
885	pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL	899	pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL
886		900
887	int rdlen_offs = offs += 2;	901	int rdlen_offs = offs += 2;
888		902
		903	if (dns)
		904	{
889	int dlen = (dns ? ntohs (dns->cfg.max_size) : MAX_PKT_SIZE) - offs;	905	int dlen = ntohs (dns->cfg.max_size) - offs;
		906
890	// bind doesn't compress well, so reduce further by one label length	907	// bind doesn't compress well, so reduce further by one label length
891	dlen -= qlen;	908	dlen -= qlen;
892		909
893	if (dns)
894	{
895	// only put data into in-order sequence packets, if	910	// only put data into in-order sequence packets, if
896	// we receive out-of-order packets we generate empty	911	// we receive out-of-order packets we generate empty
897	// replies	912	// replies
898	while (dlen > 1 && !dns->snddq.empty () && in_seq)	913	//printf ("%d - %d & %x (=%d) < %d\n", seqno, dns->repseq, SEQNO_MASK, (seqno - dns->repseq) & SEQNO_MASK, MAX_WINDOW);//D
		914	if (((seqno - dns->repseq) & SEQNO_MASK) <= MAX_WINDOW)
899	{	915	{
		916	dns->repseq = seqno;
		917
		918	while (dlen > 1 && !dns->snddq.empty ())
		919	{
900	int txtlen = dlen <= 255 ? dlen - 1 : 255;	920	int txtlen = dlen <= 255 ? dlen - 1 : 255;
901		921
902	if (txtlen > dns->snddq.size ())	922	if (txtlen > dns->snddq.size ())
903	txtlen = dns->snddq.size ();	923	txtlen = dns->snddq.size ();
904		924
905	pkt[offs++] = txtlen;	925	pkt[offs++] = txtlen;
906	memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);	926	memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);
907	offs += txtlen;	927	offs += txtlen;
908	dns->snddq.remove (txtlen);	928	dns->snddq.remove (txtlen);
909		929
910	dlen -= txtlen + 1;	930	dlen -= txtlen + 1;
		931	}
911	}	932	}
912		933
913	// avoid empty TXT rdata	934	// avoid completely empty TXT rdata
914	if (offs == rdlen_offs)	935	if (offs == rdlen_offs)
915	pkt[offs++] = 0;	936	pkt[offs++] = 0;
916		937
917	slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ());	938	slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ());
918	}	939	}
919	else	940	else
920	{	941	{
921	// send RST	942	// send RST
922	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;	943	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
923	pkt [offs++] = CMD_IP_RST;	944	pkt [offs++] = CMD_IP_RST;
924	}	945	}
925		946
926	int rdlen = offs - rdlen_offs;	947	int rdlen = offs - rdlen_offs;
927		948
928	pkt [rdlen_offs - 2] = rdlen >> 8;	949	pkt [rdlen_offs - 2] = rdlen >> 8;
929	pkt [rdlen_offs - 1] = rdlen;	950	pkt [rdlen_offs - 1] = rdlen;
930		951
931	if (dns)	952	if (dns)
932	{	953	{
933	// now update dns_rcv copy	954	// now update dns_rcv copy
934	rcv->pkt->len = offs;	955	rcv->pkt->len = offs;
935	memcpy (rcv->pkt->at (0), pkt.at (0), offs);	956	memcpy (rcv->pkt->at (0), pkt.at (0), offs);
936	}	957	}
		958	}
937		959
938	duplicate_request: ;	960	duplicate_request: ;
939	}	961	}
940	else	962	else
941	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);	963	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);
…		…
953	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class	975	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
954	pkt [offs++] = 0; pkt [offs++] = 0;	976	pkt [offs++] = 0; pkt [offs++] = 0;
955	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL	977	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL
956	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength	978	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength
957		979
958	slog (L_INFO, _("DNS: client %d tries to connect"), client);	980	slog (L_INFO, _("DNS: client %d connects"), client);
959		981
960	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;	982	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
961	pkt [offs++] = CMD_IP_REJ;	983	pkt [offs++] = CMD_IP_REJ;
962		984
963	if (0 < client && client <= conns.size ())	985	if (0 < client && client <= conns.size ())
…		…
997	{	1019	{
998	dns_connection dns = (i)->dns;	1020	dns_connection dns = (i)->dns;
999	connection *c = dns->c;	1021	connection *c = dns->c;
1000	int seqno = (*i)->seqno;	1022	int seqno = (*i)->seqno;
1001	u8 data[MAXSIZE], *datap = data;	1023	u8 data[MAXSIZE], *datap = data;
		1024	//printf ("rcv pkt %x\n", seqno);//D
1002		1025
1003	if ((*i)->retry)	1026	if ((*i)->retry)
1004	{	1027	{
1005	dns->send_interval *= 1.01;	1028	dns->send_interval *= 1.01;
1006	if (dns->send_interval > MAX_SEND_INTERVAL)	1029	if (dns->send_interval > MAX_SEND_INTERVAL)
1007	dns->send_interval = MAX_SEND_INTERVAL;	1030	dns->send_interval = MAX_SEND_INTERVAL;
1008	}	1031	}
1009	else	1032	else
1010	{	1033	{
1011	#if 1	1034	#if 0
1012	dns->send_interval *= 0.999;	1035	dns->send_interval *= 0.999;
1013	#endif	1036	#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	1037	// the latency surely puts an upper bound on
1018	// the minimum send interval	1038	// the minimum send interval
1019	double latency = NOW - (*i)->sent;	1039	double latency = ev_now () - (*i)->sent;
		1040
		1041	if (latency < dns->min_latency)
1020	dns->last_latency = latency;	1042	dns->min_latency = latency;
1021		1043
1022	if (dns->send_interval > latency)	1044	if (dns->send_interval > dns->min_latency * conf.dns_overlap_factor)
		1045	dns->send_interval = dns->min_latency * conf.dns_overlap_factor;
		1046
		1047	if (dns->send_interval < conf.dns_send_interval)
1023	dns->send_interval = latency;	1048	dns->send_interval = conf.dns_send_interval;
1024	}	1049	}
1025		1050
1026	delete *i;	1051	delete *i;
1027	dns_sndpq.erase (i);	1052	dns_sndpq.erase (i);
1028		1053
…		…
1133	break;	1158	break;
1134	}	1159	}
1135	}	1160	}
1136		1161
1137	void	1162	void
1138	vpn::dnsv4_ev (io_watcher &w, short revents)	1163	vpn::dnsv4_ev (ev::io &w, int revents)
1139	{	1164	{
1140	if (revents & EVENT_READ)	1165	if (revents & EV_READ)
1141	{	1166	{
1142	dns_packet *pkt = new dns_packet;	1167	dns_packet *pkt = new dns_packet;
1143	struct sockaddr_in sa;	1168	struct sockaddr_in sa;
1144	socklen_t sa_len = sizeof (sa);	1169	socklen_t sa_len = sizeof (sa);
1145		1170
1146	pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len);	1171	pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len);
1147		1172
1148	if (pkt->len > 0)	1173	if (pkt->len > 0)
1149	{	1174	{
1150	if (THISNODE->dns_port)	1175	if (ntohs (pkt->flags) & FLAG_RESPONSE)
		1176	dnsv4_client (*pkt);
		1177	else
1151	{	1178	{
1152	dnsv4_server (*pkt);	1179	dnsv4_server (*pkt);
1153	sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len);	1180	sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len);
1154	}	1181	}
1155	else
1156	dnsv4_client (*pkt);
1157		1182
1158	delete pkt;	1183	delete pkt;
1159	}	1184	}
1160	}	1185	}
1161	}	1186	}
1162		1187
1163	bool	1188	bool
1164	vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)	1189	vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)
1165	{	1190	{
1166	int client = ntohs (si.port);	1191	int client = ntohl (si.host);
1167		1192
1168	assert (0 < client && client <= conns.size ());	1193	assert (0 < client && client <= conns.size ());
1169		1194
1170	connection *c = conns [client - 1];	1195	connection *c = conns [client - 1];
1171		1196
1172	if (!c->dns)	1197	if (!c->dns)
1173	c->dns = new dns_connection (c);	1198	c->dns = new dns_connection (c);
1174		1199
1175	if (!c->dns->snddq.put (pkt))	1200	if (c->dns->snddq.put (pkt))
1176	return false;
1177
1178	c->dns->tw.trigger ();	1201	c->dns->tw ();
1179		1202
		1203	// always return true even if the buffer overflows
1180	return true;	1204	return true;
1181	}	1205	}
1182		1206
1183	void	1207	void
1184	connection::dnsv4_reset_connection ()	1208	connection::dnsv4_reset_connection ()
…		…
1187	}	1211	}
1188		1212
1189	#define NEXT(w) do { if (next > (w)) next = w; } while (0)	1213	#define NEXT(w) do { if (next > (w)) next = w; } while (0)
1190		1214
1191	void	1215	void
1192	dns_connection::time_cb (time_watcher &w)	1216	dns_connection::time_cb (ev::timer &w, int revents)
1193	{	1217	{
1194	// servers have to be polled	1218	// servers have to be polled
1195	if (THISNODE->dns_port)	1219	if (THISNODE->dns_port)
1196	return;	1220	return;
1197		1221
1198	// check for timeouts and (re)transmit	1222	// check for timeouts and (re)transmit
1199	tstamp next = NOW + poll_interval;	1223	tstamp next = ev::now () + poll_interval;
1200	dns_snd *send = 0;	1224	dns_snd *send = 0;
1201		1225
1202	for (vector<dns_snd *>::iterator i = vpn->dns_sndpq.begin ();	1226	for (vector<dns_snd *>::iterator i = vpn->dns_sndpq.begin ();
1203	i != vpn->dns_sndpq.end ();	1227	i != vpn->dns_sndpq.end ();
1204	++i)	1228	++i)
1205	{	1229	{
1206	dns_snd r = i;	1230	dns_snd r = i;
1207		1231
1208	if (r->timeout <= NOW)	1232	if (r->timeout <= ev_now ())
1209	{	1233	{
1210	if (!send)	1234	if (!send)
1211	{	1235	{
1212	send = r;	1236	send = r;
1213		1237
1214	r->retry++;	1238	r->retry++;
1215	r->timeout = NOW + (r->retry * last_latency * 8.);	1239	r->timeout = ev_now () + (r->retry * min_latency * conf.dns_timeout_factor);
		1240	//printf ("RETRY %x (%d, %f)\n", r->seqno, r->retry, r->timeout - ev_now ());//D
1216		1241
1217	// the following code changes the query section a bit, forcing	1242	// the following code changes the query section a bit, forcing
1218	// the forwarder to generate a new request	1243	// the forwarder to generate a new request
1219	if (r->stdhdr)	1244	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);	1245	encode_header ((char )r->pkt->at (6 2 + 1), THISNODE->id, r->seqno, r->retry);
1223	}
1224	}	1246	}
1225	}	1247	}
1226	else	1248	else
1227	NEXT (r->timeout);	1249	NEXT (r->timeout);
1228	}	1250	}
1229		1251
1230	if (last_sent + send_interval <= NOW)
1231	{
1232	if (!send)	1252	if (!send)
		1253	{
		1254	// generate a new packet, if wise
		1255
		1256	if (!established)
1233	{	1257	{
1234	// generate a new packet, if wise	1258	if (vpn->dns_sndpq.empty ())
1235
1236	if (!established)
1237	{	1259	{
1238	if (vpn->dns_sndpq.empty ())
1239	{
1240	send = new dns_snd (this);	1260	send = new dns_snd (this);
1241		1261
1242	printf ("new conn %p %d\n", this, c->conf->id);//D
1243	cfg.reset (THISNODE->id);	1262	cfg.reset (THISNODE->id);
1244	send->gen_syn_req ();	1263	send->gen_syn_req ();
1245	}
1246	}	1264	}
1247	else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING	1265	}
		1266	else if (vpn->dns_sndpq.size () < conf.dns_max_outstanding
1248	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))	1267	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
		1268	{
		1269	if (last_sent + send_interval <= ev_now ())
1249	{	1270	{
1250	//printf ("sending data request etc.\n"); //D	1271	//printf ("sending data request etc.\n"); //D
1251	if (!snddq.empty ())	1272	if (!snddq.empty () \|\| last_received + 1. > ev_now ())
1252	{	1273	{
1253	poll_interval = send_interval;	1274	poll_interval = send_interval;
1254	NEXT (NOW + send_interval);	1275	NEXT (ev_now () + send_interval);
1255	}	1276	}
1256		1277
1257	send = new dns_snd (this);	1278	send = new dns_snd (this);
1258	send->gen_stream_req (sndseq, snddq);	1279	send->gen_stream_req (sndseq, snddq);
1259	send->timeout = NOW + last_latency * 8.;	1280	send->timeout = ev_now () + min_latency * conf.dns_timeout_factor;
		1281	//printf ("SEND %x (%f)\n", send->seqno, send->timeout - ev_now (), min_latency, conf.dns_timeout_factor);//D
1260		1282
1261	sndseq = (sndseq + 1) & SEQNO_MASK;	1283	sndseq = (sndseq + 1) & SEQNO_MASK;
1262	}	1284	}
1263		1285	else
1264	if (send)	1286	NEXT (last_sent + send_interval);
1265	vpn->dns_sndpq.push_back (send);
1266	}	1287	}
1267		1288
1268	if (send)	1289	if (send)
1269	{	1290	vpn->dns_sndpq.push_back (send);
1270	last_sent = NOW;	1291	}
		1292
		1293	if (send)
		1294	{
		1295	last_sent = ev_now ();
1271	sendto (vpn->dnsv4_fd,	1296	sendto (vpn->dnsv4_fd,
1272	send->pkt->at (0), send->pkt->len, 0,	1297	send->pkt->at (0), send->pkt->len, 0,
1273	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());	1298	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
1274	}
1275	}	1299	}
1276	else
1277	NEXT (last_sent + send_interval);
1278		1300
1279	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d)",	1301	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",
1280	poll_interval, send_interval, next - NOW,	1302	poll_interval, send_interval, next - ev_now (),
1281	vpn->dns_sndpq.size (), snddq.size ());	1303	vpn->dns_sndpq.size (), snddq.size (),
		1304	rcvpq.size ());
1282		1305
1283	// TODO: no idea when this happens, but when next < NOW, we have a problem	1306	// TODO: no idea when this happens, but when next < ev_now (), we have a problem
		1307	// doesn't seem to happen anymore
1284	if (next < NOW + 0.0001)	1308	if (next < ev_now () + 0.001)
1285	next = NOW + 0.1;	1309	next = ev_now () + 0.1;
1286		1310
1287	w.start (next);	1311	w.start (next - ev_now ());
1288	}	1312	}
1289		1313
1290	#endif	1314	#endif
1291		1315

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing gvpe/src/vpn_dns.C (file contents): Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC vs. Revision 1.46 by pcg, Thu Dec 6 00:35:29 2007 UTC

Diff Legend

Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC vs.
Revision 1.46 by pcg, Thu Dec 6 00:35:29 2007 UTC