[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 1.40 by pcg, Sat Jul 9 20:29:29 2005 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>
…		…
43		48
44	#include "netcompat.h"	49	#include "netcompat.h"
45		50
46	#include "vpn.h"	51	#include "vpn.h"
47		52
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	53	#define MAX_POLL_INTERVAL 5. // how often to poll minimally when the server has no data
50	#define ACTIVITY_INTERVAL 5.	54	#define ACTIVITY_INTERVAL 5.
51		55
52	#define INITIAL_TIMEOUT 0.1 // retry timeouts	56	#define INITIAL_TIMEOUT 0.1 // retry timeouts
53	#define INITIAL_SYN_TIMEOUT 10. // retry timeout for initial syn	57	#define INITIAL_SYN_TIMEOUT 2. // retry timeout for initial syn
54		58
55	#define MIN_SEND_INTERVAL 0.01 // wait at least this time between sending requests
56	#define MAX_SEND_INTERVAL 0.5 // optimistic?	59	#define MAX_SEND_INTERVAL 2. // optimistic?
57		60
58	#define MAX_OUTSTANDING 10 // max. outstanding requests
59	#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING, and backlog	61	#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	62	#define MAX_BACKLOG (64*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE
61		63
62	#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well	64	#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	65	// 240 leaves about 4 bytes of server reply data
64	// every two request bytes less give room for one reply byte	66	// every request byte less give room for two reply bytes
65		67
66	#define SEQNO_MASK 0x3fff	68	#define SEQNO_MASK 0x3fff
67	#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )	69	#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )
68		70
69	#define MAX_LBL_SIZE 63	71	#define MAX_LBL_SIZE 63
…		…
264	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");	266	static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");
265		267
266	/////////////////////////////////////////////////////////////////////////////	268	/////////////////////////////////////////////////////////////////////////////
267		269
268	#define HDRSIZE 6	270	#define HDRSIZE 6
269		271
270	inline void encode_header (char *data, int clientid, int seqno, int retry = 0)	272	inline void encode_header (char *data, int clientid, int seqno, int retry = 0)
271	{	273	{
272	seqno &= SEQNO_MASK;	274	seqno &= SEQNO_MASK;
273		275
274	u8 hdr[3] = {	276	u8 hdr[3] = {
…		…
408	struct dns_cfg	410	struct dns_cfg
409	{	411	{
410	static int next_uid;	412	static int next_uid;
411		413
412	u8 id1, id2, id3, id4;	414	u8 id1, id2, id3, id4;
		415
413	u8 version;	416	u8 version;
		417	u8 flags;
414	u8 rrtype;	418	u8 rrtype;
415	u8 flags;
416	u8 def_ttl;	419	u8 def_ttl;
417	u8 rcv_cdc;	420
418	u8 snd_cdc;
419	u16 max_size;
420	u16 client;	421	u16 client;
421	u16 uid; // to make request unique	422	u16 uid; // to make request unique
422		423
423	u8 reserved[8];	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;
424		433
425	void reset (int clientid);	434	void reset (int clientid);
426	bool valid ();	435	bool valid ();
427	};	436	};
428		437
…		…
437		446
438	version = 1;	447	version = 1;
439		448
440	rrtype = RR_TYPE_TXT;	449	rrtype = RR_TYPE_TXT;
441	flags = 0;	450	flags = 0;
442	def_ttl = 1;	451	def_ttl = 0;
		452	seq_cdc = 26;
		453	req_cdc = 62;
443	rcv_cdc = 0;	454	rep_cdc = 0;
444	snd_cdc = 62;
445	max_size = ntohs (MAX_PKT_SIZE);	455	max_size = htons (MAX_PKT_SIZE);
446	client = ntohs (clientid);	456	client = htons (clientid);
447	uid = next_uid++;	457	uid = next_uid++;
		458	delay = 0;
448		459
449	memset (reserved, 0, 8);	460	r3 = r4 = 0;
		461	r4 = r5 = r6 = r7 = 0;
450	}	462	}
451		463
452	bool dns_cfg::valid ()	464	bool dns_cfg::valid ()
453	{	465	{
		466	// although the protocol itself allows for some configurability,
		467	// only the following encoding/decoding settings are implemented.
454	return id1 == 'G'	468	return id1 == 'G'
455	&& id2 == 'V'	469	&& id2 == 'V'
456	&& id3 == 'P'	470	&& id3 == 'P'
457	&& id4 == 'E'	471	&& id4 == 'E'
		472	&& seq_cdc == 26
		473	&& req_cdc == 62
		474	&& rep_cdc == 0
458	&& version == 1	475	&& version == 1;
459	&& flags == 0
460	&& rcv_cdc == 0
461	&& snd_cdc == 62
462	&& max_size == ntohs (MAX_PKT_SIZE);
463	}	476	}
464		477
465	struct dns_packet : net_packet	478	struct dns_packet : net_packet
466	{	479	{
467	u16 id;	480	u16 id;
468	u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4	481	u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4
469	u16 qdcount, ancount, nscount, arcount;	482	u16 qdcount, ancount, nscount, arcount;
470		483
471	u8 data[MAXSIZE - 6 * 2];	484	u8 data [MAXSIZE - 6 * 2];
472		485
473	int decode_label (char *data, int size, int &offs);	486	int decode_label (char *data, int size, int &offs);
474	};	487	};
475		488
476	int dns_packet::decode_label (char *data, int size, int &offs)	489	int dns_packet::decode_label (char *data, int size, int &offs)
…		…
538		551
539	bool established;	552	bool established;
540		553
541	tstamp last_received;	554	tstamp last_received;
542	tstamp last_sent;	555	tstamp last_sent;
543	double last_latency;	556	double min_latency;
544	double poll_interval, send_interval;	557	double poll_interval, send_interval;
545		558
546	vector<dns_rcv *> rcvpq;	559	vector<dns_rcv *> rcvpq;
547		560
548	byte_stream rcvdq; int rcvseq;	561	byte_stream rcvdq; int rcvseq; int repseq;
549	byte_stream snddq; int sndseq;	562	byte_stream snddq; int sndseq;
550		563
551	void time_cb (time_watcher &w); time_watcher tw;	564	void time_cb (time_watcher &w); time_watcher tw;
552	void receive_rep (dns_rcv *r);	565	void receive_rep (dns_rcv *r);
553		566
…		…
622		635
623	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	636	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
624	pkt->qdcount = htons (1);	637	pkt->qdcount = htons (1);
625		638
626	int offs = 6*2;	639	int offs = 6*2;
627	int dlen = MAX_DOMAIN_SIZE - (strlen (THISNODE->domain) + 2);	640	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,	641	// 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	642	// so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra
630		643
631	char enc[256], *encp = enc;	644	char enc[256], *encp = enc;
632	encode_header (enc, THISNODE->id, seqno);	645	encode_header (enc, THISNODE->id, seqno);
…		…
650	encp += lbllen;	663	encp += lbllen;
651		664
652	enclen -= lbllen;	665	enclen -= lbllen;
653	}	666	}
654		667
655	append_domain (*pkt, offs, THISNODE->domain);	668	append_domain (*pkt, offs, dns->c->conf->domain);
656		669
657	(*pkt)[offs++] = 0;	670	(*pkt)[offs++] = 0;
658	(pkt)[offs++] = RR_TYPE_ANY >> 8; (pkt)[offs++] = RR_TYPE_ANY;	671	(pkt)[offs++] = RR_TYPE_ANY >> 8; (pkt)[offs++] = RR_TYPE_ANY;
659	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;	672	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
660		673
…		…
663		676
664	void dns_snd::gen_syn_req ()	677	void dns_snd::gen_syn_req ()
665	{	678	{
666	timeout = NOW + INITIAL_SYN_TIMEOUT;	679	timeout = NOW + INITIAL_SYN_TIMEOUT;
667		680
668	printf ("send syn\n");//D
669
670	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);	681	pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
671	pkt->qdcount = htons (1);	682	pkt->qdcount = htons (1);
672		683
673	int offs = 6 * 2;	684	int offs = 6 * 2;
674		685
…		…
676		687
677	assert (elen <= MAX_LBL_SIZE);	688	assert (elen <= MAX_LBL_SIZE);
678		689
679	(*pkt)[offs] = elen;	690	(*pkt)[offs] = elen;
680	offs += elen + 1;	691	offs += elen + 1;
681	append_domain (*pkt, offs, THISNODE->domain);	692	append_domain (*pkt, offs, dns->c->conf->domain);
682		693
683	(*pkt)[offs++] = 0;	694	(*pkt)[offs++] = 0;
684	(pkt)[offs++] = RR_TYPE_A >> 8; (pkt)[offs++] = RR_TYPE_A;	695	(pkt)[offs++] = RR_TYPE_A >> 8; (pkt)[offs++] = RR_TYPE_A;
685	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;	696	(pkt)[offs++] = RR_CLASS_IN >> 8; (pkt)[offs++] = RR_CLASS_IN;
686		697
…		…
712	/////////////////////////////////////////////////////////////////////////////	723	/////////////////////////////////////////////////////////////////////////////
713		724
714	dns_connection::dns_connection (connection *c)	725	dns_connection::dns_connection (connection *c)
715	: c (c)	726	: c (c)
716	, rcvdq (MAX_BACKLOG * 2)	727	, rcvdq (MAX_BACKLOG * 2)
717	, snddq (MAX_BACKLOG * 2)	728	, snddq (MAX_BACKLOG)
718	, tw (this, &dns_connection::time_cb)	729	, tw (this, &dns_connection::time_cb)
719	{	730	{
720	vpn = c->vpn;	731	vpn = c->vpn;
721		732
722	established = false;	733	established = false;
723		734
724	rcvseq = sndseq = 0;	735	rcvseq = repseq = sndseq = 0;
725		736
726	last_sent = last_received = 0;	737	last_sent = last_received = 0;
727	poll_interval = MIN_POLL_INTERVAL;	738	poll_interval = 0.5; // starting here
728	send_interval = 0.5; // starting rate	739	send_interval = 0.5; // starting rate
729	last_latency = INITIAL_TIMEOUT;	740	min_latency = INITIAL_TIMEOUT;
730	}	741	}
731		742
732	dns_connection::~dns_connection ()	743	dns_connection::~dns_connection ()
733	{	744	{
734	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();	745	for (vector<dns_rcv *>::iterator i = rcvpq.begin ();
…		…
747	poll_interval = send_interval;	758	poll_interval = send_interval;
748	}	759	}
749	else	760	else
750	{	761	{
751	poll_interval *= 1.5;	762	poll_interval *= 1.5;
		763
752	if (poll_interval > MAX_POLL_INTERVAL)	764	if (poll_interval > MAX_POLL_INTERVAL)
753	poll_interval = MAX_POLL_INTERVAL;	765	poll_interval = MAX_POLL_INTERVAL;
754	}	766	}
755		767
756	rcvpq.push_back (r);	768	rcvpq.push_back (r);
…		…
782	}	794	}
783		795
784	while (vpn_packet *pkt = rcvdq.get ())	796	while (vpn_packet *pkt = rcvdq.get ())
785	{	797	{
786	sockinfo si;	798	sockinfo si;
787	si.host = 0x01010101; si.port = htons (c->conf->id); si.prot = PROT_DNSv4;	799	si.host = htonl (c->conf->id); si.port = 0; si.prot = PROT_DNSv4;
788		800
789	vpn->recv_vpn_packet (pkt, si);	801	vpn->recv_vpn_packet (pkt, si);
790		802
791	delete pkt;	803	delete pkt;
792	}	804	}
…		…
806	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);	818	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);
807		819
808	if (0 == (flags & (FLAG_RESPONSE \| FLAG_OP_MASK))	820	if (0 == (flags & (FLAG_RESPONSE \| FLAG_OP_MASK))
809	&& pkt.qdcount == htons (1))	821	&& pkt.qdcount == htons (1))
810	{	822	{
811	char qname[MAXSIZE];	823	char qname [MAXSIZE];
812	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);	824	int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
813		825
814	u16 qtype = pkt [offs++] << 8; qtype \|= pkt [offs++];	826	u16 qtype = pkt [offs++] << 8; qtype \|= pkt [offs++];
815	u16 qclass = pkt [offs++] << 8; qclass \|= pkt [offs++];	827	u16 qclass = pkt [offs++] << 8; qclass \|= pkt [offs++];
816		828
…		…
823		835
824	int dlen = strlen (THISNODE->domain);	836	int dlen = strlen (THISNODE->domain);
825		837
826	if (qclass == RR_CLASS_IN	838	if (qclass == RR_CLASS_IN
827	&& qlen > dlen + 1	839	&& qlen > dlen + 1
828	&& !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen))	840	&& !memcmp (qname + qlen - (dlen + 1), THISNODE->domain, dlen))
829	{	841	{
830	// now generate reply	842	// now generate reply
831	pkt.ancount = htons (1); // one answer RR	843	pkt.ancount = htons (1); // one answer RR
832	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_OK);	844	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_OK);
833		845
…		…
846	if (0 < client && client <= conns.size ())	858	if (0 < client && client <= conns.size ())
847	{	859	{
848	connection *c = conns [client - 1];	860	connection *c = conns [client - 1];
849	dns_connection *dns = c->dns;	861	dns_connection *dns = c->dns;
850	dns_rcv *rcv;	862	dns_rcv *rcv;
851	bool in_seq;
852		863
853	if (dns)	864	if (dns)
854	{	865	{
855	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )	866	for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )
856	if (SEQNO_EQ ((*i)->seqno, seqno))	867	if (SEQNO_EQ ((*i)->seqno, seqno))
…		…
867	memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len);	878	memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len);
868		879
869	goto duplicate_request;	880	goto duplicate_request;
870	}	881	}
871		882
872	in_seq = dns->rcvseq == seqno;
873
874	// new packet, queue	883	// new packet, queue
875	rcv = new dns_rcv (seqno, data, datalen);	884	rcv = new dns_rcv (seqno, data, datalen);
876	dns->receive_rep (rcv);	885	dns->receive_rep (rcv);
877	}	886	}
878		887
		888	{
879	pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section	889	pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section
880		890
881	int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A;	891	int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A;
882	pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type	892	pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type
883	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class	893	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
884	pkt [offs++] = 0; pkt [offs++] = 0;	894	pkt [offs++] = 0; pkt [offs++] = 0;
885	pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL	895	pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL
886		896
887	int rdlen_offs = offs += 2;	897	int rdlen_offs = offs += 2;
888		898
		899	if (dns)
		900	{
889	int dlen = (dns ? ntohs (dns->cfg.max_size) : MAX_PKT_SIZE) - offs;	901	int dlen = ntohs (dns->cfg.max_size) - offs;
		902
890	// bind doesn't compress well, so reduce further by one label length	903	// bind doesn't compress well, so reduce further by one label length
891	dlen -= qlen;	904	dlen -= qlen;
892		905
893	if (dns)
894	{
895	// only put data into in-order sequence packets, if	906	// only put data into in-order sequence packets, if
896	// we receive out-of-order packets we generate empty	907	// we receive out-of-order packets we generate empty
897	// replies	908	// replies
898	while (dlen > 1 && !dns->snddq.empty () && in_seq)	909	//printf ("%d - %d & %x (=%d) < %d\n", seqno, dns->repseq, SEQNO_MASK, (seqno - dns->repseq) & SEQNO_MASK, MAX_WINDOW);//D
		910	if (((seqno - dns->repseq) & SEQNO_MASK) <= MAX_WINDOW)
899	{	911	{
		912	dns->repseq = seqno;
		913
		914	while (dlen > 1 && !dns->snddq.empty ())
		915	{
900	int txtlen = dlen <= 255 ? dlen - 1 : 255;	916	int txtlen = dlen <= 255 ? dlen - 1 : 255;
901		917
902	if (txtlen > dns->snddq.size ())	918	if (txtlen > dns->snddq.size ())
903	txtlen = dns->snddq.size ();	919	txtlen = dns->snddq.size ();
904		920
905	pkt[offs++] = txtlen;	921	pkt[offs++] = txtlen;
906	memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);	922	memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);
907	offs += txtlen;	923	offs += txtlen;
908	dns->snddq.remove (txtlen);	924	dns->snddq.remove (txtlen);
909		925
910	dlen -= txtlen + 1;	926	dlen -= txtlen + 1;
		927	}
911	}	928	}
912		929
913	// avoid empty TXT rdata	930	// avoid completely empty TXT rdata
914	if (offs == rdlen_offs)	931	if (offs == rdlen_offs)
915	pkt[offs++] = 0;	932	pkt[offs++] = 0;
916		933
917	slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ());	934	slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ());
918	}	935	}
919	else	936	else
920	{	937	{
921	// send RST	938	// send RST
922	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;	939	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
923	pkt [offs++] = CMD_IP_RST;	940	pkt [offs++] = CMD_IP_RST;
924	}	941	}
925		942
926	int rdlen = offs - rdlen_offs;	943	int rdlen = offs - rdlen_offs;
927		944
928	pkt [rdlen_offs - 2] = rdlen >> 8;	945	pkt [rdlen_offs - 2] = rdlen >> 8;
929	pkt [rdlen_offs - 1] = rdlen;	946	pkt [rdlen_offs - 1] = rdlen;
930		947
931	if (dns)	948	if (dns)
932	{	949	{
933	// now update dns_rcv copy	950	// now update dns_rcv copy
934	rcv->pkt->len = offs;	951	rcv->pkt->len = offs;
935	memcpy (rcv->pkt->at (0), pkt.at (0), offs);	952	memcpy (rcv->pkt->at (0), pkt.at (0), offs);
936	}	953	}
		954	}
937		955
938	duplicate_request: ;	956	duplicate_request: ;
939	}	957	}
940	else	958	else
941	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);	959	pkt.flags = htons (DEFAULT_SERVER_FLAGS \| FLAG_RCODE_FORMERR);
…		…
953	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class	971	pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
954	pkt [offs++] = 0; pkt [offs++] = 0;	972	pkt [offs++] = 0; pkt [offs++] = 0;
955	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL	973	pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL
956	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength	974	pkt [offs++] = 0; pkt [offs++] = 4; // rdlength
957		975
958	slog (L_INFO, _("DNS: client %d tries to connect"), client);	976	slog (L_INFO, _("DNS: client %d connects"), client);
959		977
960	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;	978	pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
961	pkt [offs++] = CMD_IP_REJ;	979	pkt [offs++] = CMD_IP_REJ;
962		980
963	if (0 < client && client <= conns.size ())	981	if (0 < client && client <= conns.size ())
…		…
1006	if (dns->send_interval > MAX_SEND_INTERVAL)	1024	if (dns->send_interval > MAX_SEND_INTERVAL)
1007	dns->send_interval = MAX_SEND_INTERVAL;	1025	dns->send_interval = MAX_SEND_INTERVAL;
1008	}	1026	}
1009	else	1027	else
1010	{	1028	{
1011	#if 1	1029	#if 0
1012	dns->send_interval *= 0.999;	1030	dns->send_interval *= 0.999;
1013	#endif	1031	#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	1032	// the latency surely puts an upper bound on
1018	// the minimum send interval	1033	// the minimum send interval
1019	double latency = NOW - (*i)->sent;	1034	double latency = NOW - (*i)->sent;
		1035
		1036	if (latency < dns->min_latency)
1020	dns->last_latency = latency;	1037	dns->min_latency = latency;
1021		1038
1022	if (dns->send_interval > latency)	1039	if (dns->send_interval > dns->min_latency * conf.dns_overlap_factor)
		1040	dns->send_interval = dns->min_latency * conf.dns_overlap_factor;
		1041
		1042	if (dns->send_interval < conf.dns_send_interval)
1023	dns->send_interval = latency;	1043	dns->send_interval = conf.dns_send_interval;
1024	}	1044	}
1025		1045
1026	delete *i;	1046	delete *i;
1027	dns_sndpq.erase (i);	1047	dns_sndpq.erase (i);
1028		1048
…		…
1145		1165
1146	pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len);	1166	pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len);
1147		1167
1148	if (pkt->len > 0)	1168	if (pkt->len > 0)
1149	{	1169	{
1150	if (THISNODE->dns_port)	1170	if (ntohs (pkt->flags) & FLAG_RESPONSE)
		1171	dnsv4_client (*pkt);
		1172	else
1151	{	1173	{
1152	dnsv4_server (*pkt);	1174	dnsv4_server (*pkt);
1153	sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len);	1175	sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len);
1154	}	1176	}
1155	else
1156	dnsv4_client (*pkt);
1157		1177
1158	delete pkt;	1178	delete pkt;
1159	}	1179	}
1160	}	1180	}
1161	}	1181	}
1162		1182
1163	bool	1183	bool
1164	vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)	1184	vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)
1165	{	1185	{
1166	int client = ntohs (si.port);	1186	int client = ntohl (si.host);
1167		1187
1168	assert (0 < client && client <= conns.size ());	1188	assert (0 < client && client <= conns.size ());
1169		1189
1170	connection *c = conns [client - 1];	1190	connection *c = conns [client - 1];
1171		1191
1172	if (!c->dns)	1192	if (!c->dns)
1173	c->dns = new dns_connection (c);	1193	c->dns = new dns_connection (c);
1174		1194
1175	if (!c->dns->snddq.put (pkt))	1195	if (c->dns->snddq.put (pkt))
1176	return false;
1177
1178	c->dns->tw.trigger ();	1196	c->dns->tw.trigger ();
1179		1197
		1198	// always return true even if the buffer overflows
1180	return true;	1199	return true;
1181	}	1200	}
1182		1201
1183	void	1202	void
1184	connection::dnsv4_reset_connection ()	1203	connection::dnsv4_reset_connection ()
…		…
1210	if (!send)	1229	if (!send)
1211	{	1230	{
1212	send = r;	1231	send = r;
1213		1232
1214	r->retry++;	1233	r->retry++;
1215	r->timeout = NOW + (r->retry * last_latency * 8.);	1234	r->timeout = NOW + (r->retry * min_latency * conf.dns_timeout_factor);
1216		1235
1217	// the following code changes the query section a bit, forcing	1236	// the following code changes the query section a bit, forcing
1218	// the forwarder to generate a new request	1237	// the forwarder to generate a new request
1219	if (r->stdhdr)	1238	if (r->stdhdr)
1220	{	1239	{
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);	1240	//printf ("reencoded header for ID %d retry %d:%d:%d (%p)\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);	1241	//encode_header ((char )r->pkt->at (6 2 + 1), THISNODE->id, r->seqno, r->retry);
1223	}	1242	}
1224	}	1243	}
1225	}	1244	}
1226	else	1245	else
1227	NEXT (r->timeout);	1246	NEXT (r->timeout);
1228	}	1247	}
1229		1248
1230	if (last_sent + send_interval <= NOW)
1231	{
1232	if (!send)	1249	if (!send)
		1250	{
		1251	// generate a new packet, if wise
		1252
		1253	if (!established)
1233	{	1254	{
1234	// generate a new packet, if wise	1255	if (vpn->dns_sndpq.empty ())
1235
1236	if (!established)
1237	{	1256	{
1238	if (vpn->dns_sndpq.empty ())
1239	{
1240	send = new dns_snd (this);	1257	send = new dns_snd (this);
1241		1258
1242	printf ("new conn %p %d\n", this, c->conf->id);//D
1243	cfg.reset (THISNODE->id);	1259	cfg.reset (THISNODE->id);
1244	send->gen_syn_req ();	1260	send->gen_syn_req ();
1245	}
1246	}	1261	}
1247	else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING	1262	}
		1263	else if (vpn->dns_sndpq.size () < conf.dns_max_outstanding
1248	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))	1264	&& !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
		1265	{
		1266	if (last_sent + send_interval <= NOW)
1249	{	1267	{
1250	//printf ("sending data request etc.\n"); //D	1268	//printf ("sending data request etc.\n"); //D
1251	if (!snddq.empty ())	1269	if (!snddq.empty () \|\| last_received + 1. > NOW)
1252	{	1270	{
1253	poll_interval = send_interval;	1271	poll_interval = send_interval;
1254	NEXT (NOW + send_interval);	1272	NEXT (NOW + send_interval);
1255	}	1273	}
1256		1274
1257	send = new dns_snd (this);	1275	send = new dns_snd (this);
1258	send->gen_stream_req (sndseq, snddq);	1276	send->gen_stream_req (sndseq, snddq);
1259	send->timeout = NOW + last_latency * 8.;	1277	send->timeout = NOW + min_latency * conf.dns_timeout_factor;
1260		1278
1261	sndseq = (sndseq + 1) & SEQNO_MASK;	1279	sndseq = (sndseq + 1) & SEQNO_MASK;
1262	}	1280	}
1263		1281	else
1264	if (send)	1282	NEXT (last_sent + send_interval);
1265	vpn->dns_sndpq.push_back (send);
1266	}	1283	}
1267		1284
1268	if (send)	1285	if (send)
1269	{	1286	vpn->dns_sndpq.push_back (send);
		1287	}
		1288
		1289	if (send)
		1290	{
1270	last_sent = NOW;	1291	last_sent = NOW;
1271	sendto (vpn->dnsv4_fd,	1292	sendto (vpn->dnsv4_fd,
1272	send->pkt->at (0), send->pkt->len, 0,	1293	send->pkt->at (0), send->pkt->len, 0,
1273	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());	1294	vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
1274	}
1275	}	1295	}
1276	else
1277	NEXT (last_sent + send_interval);
1278		1296
1279	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d)",	1297	slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",
1280	poll_interval, send_interval, next - NOW,	1298	poll_interval, send_interval, next - NOW,
1281	vpn->dns_sndpq.size (), snddq.size ());	1299	vpn->dns_sndpq.size (), snddq.size (),
		1300	rcvpq.size ());
1282		1301
1283	// TODO: no idea when this happens, but when next < NOW, we have a problem	1302	// TODO: no idea when this happens, but when next < NOW, we have a problem
		1303	// doesn't seem to happen anymore
1284	if (next < NOW + 0.0001)	1304	if (next < NOW + 0.001)
1285	next = NOW + 0.1;	1305	next = NOW + 0.1;
1286		1306
1287	w.start (next);	1307	w.start (next);
1288	}	1308	}
1289		1309

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Comparing gvpe/src/vpn_dns.C (file contents): Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC vs. Revision 1.40 by pcg, Sat Jul 9 20:29:29 2005 UTC

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Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.18 by pcg, Sat Mar 5 19:13:16 2005 UTC vs.
Revision 1.40 by pcg, Sat Jul 9 20:29:29 2005 UTC