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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 1.30 by pcg, Mon Mar 14 17:40:01 2005 UTC

… …
25 25
26// dns processing is EXTREMELY ugly. For obvious(?) reasons. 26// dns processing is EXTREMELY ugly. For obvious(?) reasons.
27// it's a hack, use only in emergency situations please. 27// it's a hack, use only in emergency situations please.
28 28
29#include <cstring> 29#include <cstring>
30#include <cassert>
30 31
31#include <sys/types.h> 32#include <sys/types.h>
32#include <sys/socket.h> 33#include <sys/socket.h>
33#include <sys/wait.h> 34#include <sys/wait.h>
34#include <sys/uio.h> 35#include <sys/uio.h>
… …
43 44
44#include "netcompat.h" 45#include "netcompat.h"
45 46
46#include "vpn.h" 47#include "vpn.h"
47 48
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 49#define MAX_POLL_INTERVAL 5. // how often to poll minimally when the server has no data
50#define ACTIVITY_INTERVAL 5. 50#define ACTIVITY_INTERVAL 5.
51 51
52#define INITIAL_TIMEOUT 0.1 // retry timeouts 52#define INITIAL_TIMEOUT 0.1 // retry timeouts
53#define INITIAL_SYN_TIMEOUT 10. // retry timeout for initial syn 53#define INITIAL_SYN_TIMEOUT 10. // retry timeout for initial syn
54 54
55#define MIN_SEND_INTERVAL 0.01 // wait at least this time between sending requests 55#define MIN_SEND_INTERVAL 0.001 // wait at least this time between sending requests
56#define MAX_SEND_INTERVAL 0.5 // optimistic? 56#define MAX_SEND_INTERVAL 2. // optimistic?
57 57
58#define LATENCY_FACTOR 0.5 // RTT * LATENCY_FACTOR == sending rate
58#define MAX_OUTSTANDING 10 // max. outstanding requests 59#define MAX_OUTSTANDING 2 // max. outstanding requests
59#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING, and backlog 60#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 61#define MAX_BACKLOG (100*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE
61 62
62#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well 63#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 64// 240 leaves about 4 bytes of server reply data
64// every two request bytes less give room for one reply byte 65// every two request bytes less give room for one reply byte
65 66
66#define SEQNO_MASK 0x3fff 67#define SEQNO_MASK 0x3fff
67#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) ) 68#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )
… …
264static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO"); 265static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");
265 266
266///////////////////////////////////////////////////////////////////////////// 267/////////////////////////////////////////////////////////////////////////////
267 268
268#define HDRSIZE 6 269#define HDRSIZE 6
269 270
270inline void encode_header (char *data, int clientid, int seqno, int retry = 0) 271inline void encode_header (char *data, int clientid, int seqno, int retry = 0)
271{ 272{
272 seqno &= SEQNO_MASK; 273 seqno &= SEQNO_MASK;
273 274
274 u8 hdr[3] = { 275 u8 hdr[3] = {
… …
408struct dns_cfg 409struct dns_cfg
409{ 410{
410 static int next_uid; 411 static int next_uid;
411 412
412 u8 id1, id2, id3, id4; 413 u8 id1, id2, id3, id4;
414
413 u8 version; 415 u8 version;
416 u8 flags;
414 u8 rrtype; 417 u8 rrtype;
415 u8 flags;
416 u8 def_ttl; 418 u8 def_ttl;
417 u8 rcv_cdc; 419
418 u8 snd_cdc;
419 u16 max_size;
420 u16 client; 420 u16 client;
421 u16 uid; // to make request unique 421 u16 uid; // to make request unique
422 422
423 u8 reserved[8]; 423 u16 max_size;
424 u8 seq_cdc;
425 u8 req_cdc;
426
427 u8 rep_cdc;
428 u8 delay; // time in 0.01s units that the server may delay replying packets
429 u8 r3, r4;
430
431 u8 r5, r6, r7, r8;
424 432
425 void reset (int clientid); 433 void reset (int clientid);
426 bool valid (); 434 bool valid ();
427}; 435};
428 436
… …
437 445
438 version = 1; 446 version = 1;
439 447
440 rrtype = RR_TYPE_TXT; 448 rrtype = RR_TYPE_TXT;
441 flags = 0; 449 flags = 0;
442 def_ttl = 1; 450 def_ttl = 0;
451 seq_cdc = 26;
452 req_cdc = 62;
443 rcv_cdc = 0; 453 rep_cdc = 0;
444 snd_cdc = 62;
445 max_size = ntohs (MAX_PKT_SIZE); 454 max_size = htons (MAX_PKT_SIZE);
446 client = ntohs (clientid); 455 client = htons (clientid);
447 uid = next_uid++; 456 uid = next_uid++;
457 delay = 0;
448 458
449 memset (reserved, 0, 8); 459 r3 = r4 = 0;
460 r4 = r5 = r6 = r7 = 0;
450} 461}
451 462
452bool dns_cfg::valid () 463bool dns_cfg::valid ()
453{ 464{
454 return id1 == 'G' 465 return id1 == 'G'
455 && id2 == 'V' 466 && id2 == 'V'
456 && id3 == 'P' 467 && id3 == 'P'
457 && id4 == 'E' 468 && id4 == 'E'
469 && seq_cdc == 26
470 && req_cdc == 62
471 && rep_cdc == 0
458 && version == 1 472 && version == 1;
459 && flags == 0
460 && rcv_cdc == 0
461 && snd_cdc == 62
462 && max_size == ntohs (MAX_PKT_SIZE);
463} 473}
464 474
465struct dns_packet : net_packet 475struct dns_packet : net_packet
466{ 476{
467 u16 id; 477 u16 id;
468 u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4 478 u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4
469 u16 qdcount, ancount, nscount, arcount; 479 u16 qdcount, ancount, nscount, arcount;
470 480
471 u8 data[MAXSIZE - 6 * 2]; 481 u8 data [MAXSIZE - 6 * 2];
472 482
473 int decode_label (char *data, int size, int &offs); 483 int decode_label (char *data, int size, int &offs);
474}; 484};
475 485
476int dns_packet::decode_label (char *data, int size, int &offs) 486int dns_packet::decode_label (char *data, int size, int &offs)
… …
538 548
539 bool established; 549 bool established;
540 550
541 tstamp last_received; 551 tstamp last_received;
542 tstamp last_sent; 552 tstamp last_sent;
543 double last_latency; 553 double min_latency;
544 double poll_interval, send_interval; 554 double poll_interval, send_interval;
545 555
546 vector<dns_rcv *> rcvpq; 556 vector<dns_rcv *> rcvpq;
547 557
548 byte_stream rcvdq; int rcvseq; 558 byte_stream rcvdq; int rcvseq;
… …
622 632
623 pkt->flags = htons (DEFAULT_CLIENT_FLAGS); 633 pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
624 pkt->qdcount = htons (1); 634 pkt->qdcount = htons (1);
625 635
626 int offs = 6*2; 636 int offs = 6*2;
627 int dlen = MAX_DOMAIN_SIZE - (strlen (THISNODE->domain) + 2); 637 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, 638 // 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 639 // so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra
630 640
631 char enc[256], *encp = enc; 641 char enc[256], *encp = enc;
632 encode_header (enc, THISNODE->id, seqno); 642 encode_header (enc, THISNODE->id, seqno);
… …
650 encp += lbllen; 660 encp += lbllen;
651 661
652 enclen -= lbllen; 662 enclen -= lbllen;
653 } 663 }
654 664
655 append_domain (*pkt, offs, THISNODE->domain); 665 append_domain (*pkt, offs, dns->c->conf->domain);
656 666
657 (*pkt)[offs++] = 0; 667 (*pkt)[offs++] = 0;
658 (*pkt)[offs++] = RR_TYPE_ANY >> 8; (*pkt)[offs++] = RR_TYPE_ANY; 668 (*pkt)[offs++] = RR_TYPE_ANY >> 8; (*pkt)[offs++] = RR_TYPE_ANY;
659 (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN; 669 (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN;
660 670
… …
663 673
664void dns_snd::gen_syn_req () 674void dns_snd::gen_syn_req ()
665{ 675{
666 timeout = NOW + INITIAL_SYN_TIMEOUT; 676 timeout = NOW + INITIAL_SYN_TIMEOUT;
667 677
668 printf ("send syn\n");//D
669
670 pkt->flags = htons (DEFAULT_CLIENT_FLAGS); 678 pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
671 pkt->qdcount = htons (1); 679 pkt->qdcount = htons (1);
672 680
673 int offs = 6 * 2; 681 int offs = 6 * 2;
674 682
… …
676 684
677 assert (elen <= MAX_LBL_SIZE); 685 assert (elen <= MAX_LBL_SIZE);
678 686
679 (*pkt)[offs] = elen; 687 (*pkt)[offs] = elen;
680 offs += elen + 1; 688 offs += elen + 1;
681 append_domain (*pkt, offs, THISNODE->domain); 689 append_domain (*pkt, offs, dns->c->conf->domain);
682 690
683 (*pkt)[offs++] = 0; 691 (*pkt)[offs++] = 0;
684 (*pkt)[offs++] = RR_TYPE_A >> 8; (*pkt)[offs++] = RR_TYPE_A; 692 (*pkt)[offs++] = RR_TYPE_A >> 8; (*pkt)[offs++] = RR_TYPE_A;
685 (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN; 693 (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN;
686 694
… …
722 established = false; 730 established = false;
723 731
724 rcvseq = sndseq = 0; 732 rcvseq = sndseq = 0;
725 733
726 last_sent = last_received = 0; 734 last_sent = last_received = 0;
727 poll_interval = MIN_POLL_INTERVAL; 735 poll_interval = 0.5; // starting here
728 send_interval = 0.5; // starting rate 736 send_interval = 0.5; // starting rate
729 last_latency = INITIAL_TIMEOUT; 737 min_latency = INITIAL_TIMEOUT;
730} 738}
731 739
732dns_connection::~dns_connection () 740dns_connection::~dns_connection ()
733{ 741{
734 for (vector<dns_rcv *>::iterator i = rcvpq.begin (); 742 for (vector<dns_rcv *>::iterator i = rcvpq.begin ();
… …
747 poll_interval = send_interval; 755 poll_interval = send_interval;
748 } 756 }
749 else 757 else
750 { 758 {
751 poll_interval *= 1.5; 759 poll_interval *= 1.5;
760
752 if (poll_interval > MAX_POLL_INTERVAL) 761 if (poll_interval > MAX_POLL_INTERVAL)
753 poll_interval = MAX_POLL_INTERVAL; 762 poll_interval = MAX_POLL_INTERVAL;
754 } 763 }
755 764
756 rcvpq.push_back (r); 765 rcvpq.push_back (r);
… …
806 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR); 815 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR);
807 816
808 if (0 == (flags & (FLAG_RESPONSE | FLAG_OP_MASK)) 817 if (0 == (flags & (FLAG_RESPONSE | FLAG_OP_MASK))
809 && pkt.qdcount == htons (1)) 818 && pkt.qdcount == htons (1))
810 { 819 {
811 char qname[MAXSIZE]; 820 char qname [MAXSIZE];
812 int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs); 821 int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
813 822
814 u16 qtype = pkt [offs++] << 8; qtype |= pkt [offs++]; 823 u16 qtype = pkt [offs++] << 8; qtype |= pkt [offs++];
815 u16 qclass = pkt [offs++] << 8; qclass |= pkt [offs++]; 824 u16 qclass = pkt [offs++] << 8; qclass |= pkt [offs++];
816 825
… …
823 832
824 int dlen = strlen (THISNODE->domain); 833 int dlen = strlen (THISNODE->domain);
825 834
826 if (qclass == RR_CLASS_IN 835 if (qclass == RR_CLASS_IN
827 && qlen > dlen + 1 836 && qlen > dlen + 1
828 && !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen)) 837 && !memcmp (qname + qlen - (dlen + 1), THISNODE->domain, dlen))
829 { 838 {
830 // now generate reply 839 // now generate reply
831 pkt.ancount = htons (1); // one answer RR 840 pkt.ancount = htons (1); // one answer RR
832 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_OK); 841 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_OK);
833 842
… …
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 while (dlen > 1 && !dns->snddq.empty () && in_seq)
899 { 910 {
900 int txtlen = dlen <= 255 ? dlen - 1 : 255; 911 int txtlen = dlen <= 255 ? dlen - 1 : 255;
901 912
902 if (txtlen > dns->snddq.size ()) 913 if (txtlen > dns->snddq.size ())
903 txtlen = dns->snddq.size (); 914 txtlen = dns->snddq.size ();
904 915
905 pkt[offs++] = txtlen; 916 pkt[offs++] = txtlen;
906 memcpy (pkt.at (offs), dns->snddq.begin (), txtlen); 917 memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);
907 offs += txtlen; 918 offs += txtlen;
908 dns->snddq.remove (txtlen); 919 dns->snddq.remove (txtlen);
909 920
910 dlen -= txtlen + 1; 921 dlen -= txtlen + 1;
911 } 922 }
912 923
913 // avoid empty TXT rdata 924 // avoid empty TXT rdata
914 if (offs == rdlen_offs) 925 if (offs == rdlen_offs)
915 pkt[offs++] = 0; 926 pkt[offs++] = 0;
916 927
917 slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ()); 928 slog (L_NOISE, "DNS: snddq %d", dns->snddq.size ());
918 } 929 }
919 else 930 else
920 { 931 {
921 // send RST 932 // send RST
922 pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3; 933 pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
923 pkt [offs++] = CMD_IP_RST; 934 pkt [offs++] = CMD_IP_RST;
924 } 935 }
925 936
926 int rdlen = offs - rdlen_offs; 937 int rdlen = offs - rdlen_offs;
927 938
928 pkt [rdlen_offs - 2] = rdlen >> 8; 939 pkt [rdlen_offs - 2] = rdlen >> 8;
929 pkt [rdlen_offs - 1] = rdlen; 940 pkt [rdlen_offs - 1] = rdlen;
930 941
931 if (dns) 942 if (dns)
932 { 943 {
933 // now update dns_rcv copy 944 // now update dns_rcv copy
934 rcv->pkt->len = offs; 945 rcv->pkt->len = offs;
935 memcpy (rcv->pkt->at (0), pkt.at (0), offs); 946 memcpy (rcv->pkt->at (0), pkt.at (0), offs);
936 } 947 }
948 }
937 949
938 duplicate_request: ; 950 duplicate_request: ;
939 } 951 }
940 else 952 else
941 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR); 953 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR);
… …
953 pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class 965 pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
954 pkt [offs++] = 0; pkt [offs++] = 0; 966 pkt [offs++] = 0; pkt [offs++] = 0;
955 pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL 967 pkt [offs++] = 0; pkt [offs++] = cfg.def_ttl; // TTL
956 pkt [offs++] = 0; pkt [offs++] = 4; // rdlength 968 pkt [offs++] = 0; pkt [offs++] = 4; // rdlength
957 969
958 slog (L_INFO, _("DNS: client %d tries to connect"), client); 970 slog (L_INFO, _("DNS: client %d connects"), client);
959 971
960 pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3; 972 pkt [offs++] = CMD_IP_1; pkt [offs++] = CMD_IP_2; pkt [offs++] = CMD_IP_3;
961 pkt [offs++] = CMD_IP_REJ; 973 pkt [offs++] = CMD_IP_REJ;
962 974
963 if (0 < client && client <= conns.size ()) 975 if (0 < client && client <= conns.size ())
… …
1006 if (dns->send_interval > MAX_SEND_INTERVAL) 1018 if (dns->send_interval > MAX_SEND_INTERVAL)
1007 dns->send_interval = MAX_SEND_INTERVAL; 1019 dns->send_interval = MAX_SEND_INTERVAL;
1008 } 1020 }
1009 else 1021 else
1010 { 1022 {
1011#if 1 1023#if 0
1012 dns->send_interval *= 0.999; 1024 dns->send_interval *= 0.999;
1013#endif 1025#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 1026 // the latency surely puts an upper bound on
1018 // the minimum send interval 1027 // the minimum send interval
1019 double latency = NOW - (*i)->sent; 1028 double latency = NOW - (*i)->sent;
1029
1030 if (latency < dns->min_latency)
1020 dns->last_latency = latency; 1031 dns->min_latency = latency;
1021 1032
1022 if (dns->send_interval > latency) 1033 if (dns->send_interval > dns->min_latency * LATENCY_FACTOR)
1023 dns->send_interval = latency; 1034 dns->send_interval = dns->min_latency * LATENCY_FACTOR;
1035
1036 if (dns->send_interval < MIN_SEND_INTERVAL)
1037 dns->send_interval = MIN_SEND_INTERVAL;
1024 } 1038 }
1025 1039
1026 delete *i; 1040 delete *i;
1027 dns_sndpq.erase (i); 1041 dns_sndpq.erase (i);
1028 1042
… …
1145 1159
1146 pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); 1160 pkt->len = recvfrom (w.fd, pkt->at (0), MAXSIZE, 0, (sockaddr *)&sa, &sa_len);
1147 1161
1148 if (pkt->len > 0) 1162 if (pkt->len > 0)
1149 { 1163 {
1150 if (THISNODE->dns_port) 1164 if (ntohs (pkt->flags) & FLAG_RESPONSE)
1165 dnsv4_client (*pkt);
1166 else
1151 { 1167 {
1152 dnsv4_server (*pkt); 1168 dnsv4_server (*pkt);
1153 sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len); 1169 sendto (w.fd, pkt->at (0), pkt->len, 0, (sockaddr *)&sa, sa_len);
1154 } 1170 }
1155 else
1156 dnsv4_client (*pkt);
1157 1171
1158 delete pkt; 1172 delete pkt;
1159 } 1173 }
1160 } 1174 }
1161} 1175}
… …
1210 if (!send) 1224 if (!send)
1211 { 1225 {
1212 send = r; 1226 send = r;
1213 1227
1214 r->retry++; 1228 r->retry++;
1215 r->timeout = NOW + (r->retry * last_latency * 8.); 1229 r->timeout = NOW + (r->retry * min_latency * 8.);
1216 1230
1217 // the following code changes the query section a bit, forcing 1231 // the following code changes the query section a bit, forcing
1218 // the forwarder to generate a new request 1232 // the forwarder to generate a new request
1219 if (r->stdhdr) 1233 if (r->stdhdr)
1220 { 1234 {
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); 1235 //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); 1236 //encode_header ((char *)r->pkt->at (6 * 2 + 1), THISNODE->id, r->seqno, r->retry);
1223 } 1237 }
1224 } 1238 }
1225 } 1239 }
1226 else 1240 else
1227 NEXT (r->timeout); 1241 NEXT (r->timeout);
1228 } 1242 }
1229 1243
1230 if (last_sent + send_interval <= NOW)
1231 {
1232 if (!send) 1244 if (!send)
1245 {
1246 // generate a new packet, if wise
1247
1248 if (!established)
1233 { 1249 {
1234 // generate a new packet, if wise 1250 if (vpn->dns_sndpq.empty ())
1235
1236 if (!established)
1237 { 1251 {
1238 if (vpn->dns_sndpq.empty ())
1239 {
1240 send = new dns_snd (this); 1252 send = new dns_snd (this);
1241 1253
1242 printf ("new conn %p %d\n", this, c->conf->id);//D
1243 cfg.reset (THISNODE->id); 1254 cfg.reset (THISNODE->id);
1244 send->gen_syn_req (); 1255 send->gen_syn_req ();
1245 }
1246 } 1256 }
1257 }
1247 else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING 1258 else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING
1248 && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1))) 1259 && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
1260 {
1261 if (last_sent + send_interval <= NOW)
1249 { 1262 {
1250 //printf ("sending data request etc.\n"); //D 1263 //printf ("sending data request etc.\n"); //D
1251 if (!snddq.empty ()) 1264 if (!snddq.empty () || last_received + 1. > NOW)
1252 { 1265 {
1253 poll_interval = send_interval; 1266 poll_interval = send_interval;
1254 NEXT (NOW + send_interval); 1267 NEXT (NOW + send_interval);
1255 } 1268 }
1256 1269
1257 send = new dns_snd (this); 1270 send = new dns_snd (this);
1258 send->gen_stream_req (sndseq, snddq); 1271 send->gen_stream_req (sndseq, snddq);
1259 send->timeout = NOW + last_latency * 8.; 1272 send->timeout = NOW + min_latency * 8.;
1260 1273
1261 sndseq = (sndseq + 1) & SEQNO_MASK; 1274 sndseq = (sndseq + 1) & SEQNO_MASK;
1262 } 1275 }
1263 1276 else
1264 if (send) 1277 NEXT (last_sent + send_interval);
1265 vpn->dns_sndpq.push_back (send);
1266 } 1278 }
1267 1279
1268 if (send) 1280 if (send)
1269 { 1281 vpn->dns_sndpq.push_back (send);
1282 }
1283
1284 if (send)
1285 {
1270 last_sent = NOW; 1286 last_sent = NOW;
1271 sendto (vpn->dnsv4_fd, 1287 sendto (vpn->dnsv4_fd,
1272 send->pkt->at (0), send->pkt->len, 0, 1288 send->pkt->at (0), send->pkt->len, 0,
1273 vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ()); 1289 vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
1274 }
1275 } 1290 }
1276 else
1277 NEXT (last_sent + send_interval);
1278 1291
1279 slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d)", 1292 slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",
1280 poll_interval, send_interval, next - NOW, 1293 poll_interval, send_interval, next - NOW,
1281 vpn->dns_sndpq.size (), snddq.size ()); 1294 vpn->dns_sndpq.size (), snddq.size (),
1295 rcvpq.size ());
1282 1296
1283 // TODO: no idea when this happens, but when next < NOW, we have a problem 1297 // TODO: no idea when this happens, but when next < NOW, we have a problem
1284 if (next < NOW + 0.0001) 1298 if (next < NOW + 0.001)
1285 next = NOW + 0.1; 1299 next = NOW + 0.1;
1286 1300
1287 w.start (next); 1301 w.start (next);
1288} 1302}
1289 1303

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