ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/gvpe/src/vpn_dns.C
(Generate patch)

Comparing gvpe/src/vpn_dns.C (file contents):
Revision 1.19 by pcg, Sun Mar 6 18:34:46 2005 UTC vs.
Revision 1.37 by pcg, Wed Mar 23 17:03:58 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 2. // retry timeout for initial syn
54 54
55#define MIN_SEND_INTERVAL 0.01 // wait at least this time between sending requests
56#define MAX_SEND_INTERVAL 0.5 // optimistic? 55#define MAX_SEND_INTERVAL 2. // optimistic?
57 56
58#define MAX_OUTSTANDING 10 // max. outstanding requests
59#define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING, and backlog 57#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 58#define MAX_BACKLOG (64*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE
61 59
62#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well 60#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 61// 240 leaves about 4 bytes of server reply data
64// every two request bytes less give room for one reply byte 62// every request byte less give room for two reply bytes
65 63
66#define SEQNO_MASK 0x3fff 64#define SEQNO_MASK 0x3fff
67#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) ) 65#define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) )
68 66
69#define MAX_LBL_SIZE 63 67#define MAX_LBL_SIZE 63
… …
264static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO"); 262static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO");
265 263
266///////////////////////////////////////////////////////////////////////////// 264/////////////////////////////////////////////////////////////////////////////
267 265
268#define HDRSIZE 6 266#define HDRSIZE 6
269 267
270inline void encode_header (char *data, int clientid, int seqno, int retry = 0) 268inline void encode_header (char *data, int clientid, int seqno, int retry = 0)
271{ 269{
272 seqno &= SEQNO_MASK; 270 seqno &= SEQNO_MASK;
273 271
274 u8 hdr[3] = { 272 u8 hdr[3] = {
… …
408struct dns_cfg 406struct dns_cfg
409{ 407{
410 static int next_uid; 408 static int next_uid;
411 409
412 u8 id1, id2, id3, id4; 410 u8 id1, id2, id3, id4;
411
413 u8 version; 412 u8 version;
413 u8 flags;
414 u8 rrtype; 414 u8 rrtype;
415 u8 flags;
416 u8 def_ttl; 415 u8 def_ttl;
417 u8 rcv_cdc; 416
418 u8 snd_cdc;
419 u16 max_size;
420 u16 client; 417 u16 client;
421 u16 uid; // to make request unique 418 u16 uid; // to make request unique
422 419
423 u8 reserved[8]; 420 u16 max_size;
421 u8 seq_cdc;
422 u8 req_cdc;
423
424 u8 rep_cdc;
425 u8 delay; // time in 0.01s units that the server may delay replying packets
426 u8 r3, r4;
427
428 u8 r5, r6, r7, r8;
424 429
425 void reset (int clientid); 430 void reset (int clientid);
426 bool valid (); 431 bool valid ();
427}; 432};
428 433
… …
437 442
438 version = 1; 443 version = 1;
439 444
440 rrtype = RR_TYPE_TXT; 445 rrtype = RR_TYPE_TXT;
441 flags = 0; 446 flags = 0;
442 def_ttl = 1; 447 def_ttl = 0;
448 seq_cdc = 26;
449 req_cdc = 62;
443 rcv_cdc = 0; 450 rep_cdc = 0;
444 snd_cdc = 62;
445 max_size = ntohs (MAX_PKT_SIZE); 451 max_size = htons (MAX_PKT_SIZE);
446 client = ntohs (clientid); 452 client = htons (clientid);
447 uid = next_uid++; 453 uid = next_uid++;
454 delay = 0;
448 455
449 memset (reserved, 0, 8); 456 r3 = r4 = 0;
457 r4 = r5 = r6 = r7 = 0;
450} 458}
451 459
452bool dns_cfg::valid () 460bool dns_cfg::valid ()
453{ 461{
454 return id1 == 'G' 462 return id1 == 'G'
455 && id2 == 'V' 463 && id2 == 'V'
456 && id3 == 'P' 464 && id3 == 'P'
457 && id4 == 'E' 465 && id4 == 'E'
466 && seq_cdc == 26
467 && req_cdc == 62
468 && rep_cdc == 0
458 && version == 1 469 && version == 1;
459 && flags == 0
460 && rcv_cdc == 0
461 && snd_cdc == 62
462 && max_size == ntohs (MAX_PKT_SIZE);
463} 470}
464 471
465struct dns_packet : net_packet 472struct dns_packet : net_packet
466{ 473{
467 u16 id; 474 u16 id;
468 u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4 475 u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4
469 u16 qdcount, ancount, nscount, arcount; 476 u16 qdcount, ancount, nscount, arcount;
470 477
471 u8 data[MAXSIZE - 6 * 2]; 478 u8 data [MAXSIZE - 6 * 2];
472 479
473 int decode_label (char *data, int size, int &offs); 480 int decode_label (char *data, int size, int &offs);
474}; 481};
475 482
476int dns_packet::decode_label (char *data, int size, int &offs) 483int dns_packet::decode_label (char *data, int size, int &offs)
… …
538 545
539 bool established; 546 bool established;
540 547
541 tstamp last_received; 548 tstamp last_received;
542 tstamp last_sent; 549 tstamp last_sent;
543 double last_latency; 550 double min_latency;
544 double poll_interval, send_interval; 551 double poll_interval, send_interval;
545 552
546 vector<dns_rcv *> rcvpq; 553 vector<dns_rcv *> rcvpq;
547 554
548 byte_stream rcvdq; int rcvseq; 555 byte_stream rcvdq; int rcvseq; int repseq;
549 byte_stream snddq; int sndseq; 556 byte_stream snddq; int sndseq;
550 557
551 void time_cb (time_watcher &w); time_watcher tw; 558 void time_cb (time_watcher &w); time_watcher tw;
552 void receive_rep (dns_rcv *r); 559 void receive_rep (dns_rcv *r);
553 560
… …
663 670
664void dns_snd::gen_syn_req () 671void dns_snd::gen_syn_req ()
665{ 672{
666 timeout = NOW + INITIAL_SYN_TIMEOUT; 673 timeout = NOW + INITIAL_SYN_TIMEOUT;
667 674
668 printf ("send syn\n");//D
669
670 pkt->flags = htons (DEFAULT_CLIENT_FLAGS); 675 pkt->flags = htons (DEFAULT_CLIENT_FLAGS);
671 pkt->qdcount = htons (1); 676 pkt->qdcount = htons (1);
672 677
673 int offs = 6 * 2; 678 int offs = 6 * 2;
674 679
… …
712///////////////////////////////////////////////////////////////////////////// 717/////////////////////////////////////////////////////////////////////////////
713 718
714dns_connection::dns_connection (connection *c) 719dns_connection::dns_connection (connection *c)
715: c (c) 720: c (c)
716, rcvdq (MAX_BACKLOG * 2) 721, rcvdq (MAX_BACKLOG * 2)
717, snddq (MAX_BACKLOG * 2) 722, snddq (MAX_BACKLOG)
718, tw (this, &dns_connection::time_cb) 723, tw (this, &dns_connection::time_cb)
719{ 724{
720 vpn = c->vpn; 725 vpn = c->vpn;
721 726
722 established = false; 727 established = false;
723 728
724 rcvseq = sndseq = 0; 729 rcvseq = repseq = sndseq = 0;
725 730
726 last_sent = last_received = 0; 731 last_sent = last_received = 0;
727 poll_interval = MIN_POLL_INTERVAL; 732 poll_interval = 0.5; // starting here
728 send_interval = 0.5; // starting rate 733 send_interval = 0.5; // starting rate
729 last_latency = INITIAL_TIMEOUT; 734 min_latency = INITIAL_TIMEOUT;
730} 735}
731 736
732dns_connection::~dns_connection () 737dns_connection::~dns_connection ()
733{ 738{
734 for (vector<dns_rcv *>::iterator i = rcvpq.begin (); 739 for (vector<dns_rcv *>::iterator i = rcvpq.begin ();
… …
747 poll_interval = send_interval; 752 poll_interval = send_interval;
748 } 753 }
749 else 754 else
750 { 755 {
751 poll_interval *= 1.5; 756 poll_interval *= 1.5;
757
752 if (poll_interval > MAX_POLL_INTERVAL) 758 if (poll_interval > MAX_POLL_INTERVAL)
753 poll_interval = MAX_POLL_INTERVAL; 759 poll_interval = MAX_POLL_INTERVAL;
754 } 760 }
755 761
756 rcvpq.push_back (r); 762 rcvpq.push_back (r);
… …
782 } 788 }
783 789
784 while (vpn_packet *pkt = rcvdq.get ()) 790 while (vpn_packet *pkt = rcvdq.get ())
785 { 791 {
786 sockinfo si; 792 sockinfo si;
787 si.host = 0x01010101; si.port = htons (c->conf->id); si.prot = PROT_DNSv4; 793 si.host = htonl (c->conf->id); si.port = 0; si.prot = PROT_DNSv4;
788 794
789 vpn->recv_vpn_packet (pkt, si); 795 vpn->recv_vpn_packet (pkt, si);
790 796
791 delete pkt; 797 delete pkt;
792 } 798 }
… …
806 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR); 812 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR);
807 813
808 if (0 == (flags & (FLAG_RESPONSE | FLAG_OP_MASK)) 814 if (0 == (flags & (FLAG_RESPONSE | FLAG_OP_MASK))
809 && pkt.qdcount == htons (1)) 815 && pkt.qdcount == htons (1))
810 { 816 {
811 char qname[MAXSIZE]; 817 char qname [MAXSIZE];
812 int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs); 818 int qlen = pkt.decode_label ((char *)qname, MAXSIZE - offs, offs);
813 819
814 u16 qtype = pkt [offs++] << 8; qtype |= pkt [offs++]; 820 u16 qtype = pkt [offs++] << 8; qtype |= pkt [offs++];
815 u16 qclass = pkt [offs++] << 8; qclass |= pkt [offs++]; 821 u16 qclass = pkt [offs++] << 8; qclass |= pkt [offs++];
816 822
… …
823 829
824 int dlen = strlen (THISNODE->domain); 830 int dlen = strlen (THISNODE->domain);
825 831
826 if (qclass == RR_CLASS_IN 832 if (qclass == RR_CLASS_IN
827 && qlen > dlen + 1 833 && qlen > dlen + 1
828 && !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen)) 834 && !memcmp (qname + qlen - (dlen + 1), THISNODE->domain, dlen))
829 { 835 {
830 // now generate reply 836 // now generate reply
831 pkt.ancount = htons (1); // one answer RR 837 pkt.ancount = htons (1); // one answer RR
832 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_OK); 838 pkt.flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_OK);
833 839
… …
846 if (0 < client && client <= conns.size ()) 852 if (0 < client && client <= conns.size ())
847 { 853 {
848 connection *c = conns [client - 1]; 854 connection *c = conns [client - 1];
849 dns_connection *dns = c->dns; 855 dns_connection *dns = c->dns;
850 dns_rcv *rcv; 856 dns_rcv *rcv;
851 bool in_seq;
852 857
853 if (dns) 858 if (dns)
854 { 859 {
855 for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); ) 860 for (vector<dns_rcv *>::iterator i = dns->rcvpq.end (); i-- != dns->rcvpq.begin (); )
856 if (SEQNO_EQ ((*i)->seqno, seqno)) 861 if (SEQNO_EQ ((*i)->seqno, seqno))
… …
867 memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len); 872 memcpy (pkt.at (0), r->pkt->at (0), offs = r->pkt->len);
868 873
869 goto duplicate_request; 874 goto duplicate_request;
870 } 875 }
871 876
872 in_seq = dns->rcvseq == seqno;
873
874 // new packet, queue 877 // new packet, queue
875 rcv = new dns_rcv (seqno, data, datalen); 878 rcv = new dns_rcv (seqno, data, datalen);
876 dns->receive_rep (rcv); 879 dns->receive_rep (rcv);
877 } 880 }
878 881
882 {
879 pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section 883 pkt [offs++] = 0xc0; pkt [offs++] = 6 * 2; // refer to name in query section
880 884
881 int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A; 885 int rtype = dns ? dns->cfg.rrtype : RR_TYPE_A;
882 pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type 886 pkt [offs++] = rtype >> 8; pkt [offs++] = rtype; // type
883 pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class 887 pkt [offs++] = RR_CLASS_IN >> 8; pkt [offs++] = RR_CLASS_IN; // class
884 pkt [offs++] = 0; pkt [offs++] = 0; 888 pkt [offs++] = 0; pkt [offs++] = 0;
885 pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL 889 pkt [offs++] = 0; pkt [offs++] = dns ? dns->cfg.def_ttl : 0; // TTL
886 890
887 int rdlen_offs = offs += 2; 891 int rdlen_offs = offs += 2;
888 892
893 if (dns)
894 {
889 int dlen = (dns ? ntohs (dns->cfg.max_size) : MAX_PKT_SIZE) - offs; 895 int dlen = ntohs (dns->cfg.max_size) - offs;
896
890 // bind doesn't compress well, so reduce further by one label length 897 // bind doesn't compress well, so reduce further by one label length
891 dlen -= qlen; 898 dlen -= qlen;
892 899
893 if (dns)
894 {
895 // only put data into in-order sequence packets, if 900 // only put data into in-order sequence packets, if
896 // we receive out-of-order packets we generate empty 901 // we receive out-of-order packets we generate empty
897 // replies 902 // replies
898 while (dlen > 1 && !dns->snddq.empty () && in_seq) 903 //printf ("%d - %d & %x (=%d) < %d\n", seqno, dns->repseq, SEQNO_MASK, (seqno - dns->repseq) & SEQNO_MASK, MAX_WINDOW);//D
904 if (((seqno - dns->repseq) & SEQNO_MASK) <= MAX_WINDOW)
899 { 905 {
906 dns->repseq = seqno;
907
908 while (dlen > 1 && !dns->snddq.empty ())
909 {
900 int txtlen = dlen <= 255 ? dlen - 1 : 255; 910 int txtlen = dlen <= 255 ? dlen - 1 : 255;
901 911
902 if (txtlen > dns->snddq.size ()) 912 if (txtlen > dns->snddq.size ())
903 txtlen = dns->snddq.size (); 913 txtlen = dns->snddq.size ();
904 914
905 pkt[offs++] = txtlen; 915 pkt[offs++] = txtlen;
906 memcpy (pkt.at (offs), dns->snddq.begin (), txtlen); 916 memcpy (pkt.at (offs), dns->snddq.begin (), txtlen);
907 offs += txtlen; 917 offs += txtlen;
908 dns->snddq.remove (txtlen); 918 dns->snddq.remove (txtlen);
909 919
910 dlen -= txtlen + 1; 920 dlen -= txtlen + 1;
921 }
911 } 922 }
912 923
913 // avoid empty TXT rdata 924 // avoid completely 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 * conf.dns_overlap_factor)
1034 dns->send_interval = dns->min_latency * conf.dns_overlap_factor;
1035
1036 if (dns->send_interval < conf.dns_send_interval)
1023 dns->send_interval = latency; 1037 dns->send_interval = conf.dns_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}
1162 1176
1163bool 1177bool
1164vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) 1178vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)
1165{ 1179{
1166 int client = ntohs (si.port); 1180 int client = ntohl (si.host);
1167 1181
1168 assert (0 < client && client <= conns.size ()); 1182 assert (0 < client && client <= conns.size ());
1169 1183
1170 connection *c = conns [client - 1]; 1184 connection *c = conns [client - 1];
1171 1185
1172 if (!c->dns) 1186 if (!c->dns)
1173 c->dns = new dns_connection (c); 1187 c->dns = new dns_connection (c);
1174 1188
1175 if (!c->dns->snddq.put (pkt)) 1189 if (c->dns->snddq.put (pkt))
1176 return false;
1177
1178 c->dns->tw.trigger (); 1190 c->dns->tw.trigger ();
1179 1191
1192 // always return true even if the buffer overflows
1180 return true; 1193 return true;
1181} 1194}
1182 1195
1183void 1196void
1184connection::dnsv4_reset_connection () 1197connection::dnsv4_reset_connection ()
… …
1210 if (!send) 1223 if (!send)
1211 { 1224 {
1212 send = r; 1225 send = r;
1213 1226
1214 r->retry++; 1227 r->retry++;
1215 r->timeout = NOW + (r->retry * last_latency * 8.); 1228 r->timeout = NOW + (r->retry * min_latency * conf.dns_timeout_factor);
1216 1229
1217 // the following code changes the query section a bit, forcing 1230 // the following code changes the query section a bit, forcing
1218 // the forwarder to generate a new request 1231 // the forwarder to generate a new request
1219 if (r->stdhdr) 1232 if (r->stdhdr)
1220 { 1233 {
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); 1234 //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); 1235 //encode_header ((char *)r->pkt->at (6 * 2 + 1), THISNODE->id, r->seqno, r->retry);
1223 } 1236 }
1224 } 1237 }
1225 } 1238 }
1226 else 1239 else
1227 NEXT (r->timeout); 1240 NEXT (r->timeout);
1228 } 1241 }
1229 1242
1230 if (last_sent + send_interval <= NOW)
1231 {
1232 if (!send) 1243 if (!send)
1244 {
1245 // generate a new packet, if wise
1246
1247 if (!established)
1233 { 1248 {
1234 // generate a new packet, if wise 1249 if (vpn->dns_sndpq.empty ())
1235
1236 if (!established)
1237 { 1250 {
1238 if (vpn->dns_sndpq.empty ())
1239 {
1240 send = new dns_snd (this); 1251 send = new dns_snd (this);
1241 1252
1242 printf ("new conn %p %d\n", this, c->conf->id);//D
1243 cfg.reset (THISNODE->id); 1253 cfg.reset (THISNODE->id);
1244 send->gen_syn_req (); 1254 send->gen_syn_req ();
1245 }
1246 } 1255 }
1247 else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING 1256 }
1257 else if (vpn->dns_sndpq.size () < conf.dns_max_outstanding
1248 && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1))) 1258 && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
1259 {
1260 if (last_sent + send_interval <= NOW)
1249 { 1261 {
1250 //printf ("sending data request etc.\n"); //D 1262 //printf ("sending data request etc.\n"); //D
1251 if (!snddq.empty ()) 1263 if (!snddq.empty () || last_received + 1. > NOW)
1252 { 1264 {
1253 poll_interval = send_interval; 1265 poll_interval = send_interval;
1254 NEXT (NOW + send_interval); 1266 NEXT (NOW + send_interval);
1255 } 1267 }
1256 1268
1257 send = new dns_snd (this); 1269 send = new dns_snd (this);
1258 send->gen_stream_req (sndseq, snddq); 1270 send->gen_stream_req (sndseq, snddq);
1259 send->timeout = NOW + last_latency * 8.; 1271 send->timeout = NOW + min_latency * conf.dns_timeout_factor;
1260 1272
1261 sndseq = (sndseq + 1) & SEQNO_MASK; 1273 sndseq = (sndseq + 1) & SEQNO_MASK;
1262 } 1274 }
1263 1275 else
1264 if (send) 1276 NEXT (last_sent + send_interval);
1265 vpn->dns_sndpq.push_back (send);
1266 } 1277 }
1267 1278
1268 if (send) 1279 if (send)
1269 { 1280 vpn->dns_sndpq.push_back (send);
1281 }
1282
1283 if (send)
1284 {
1270 last_sent = NOW; 1285 last_sent = NOW;
1271 sendto (vpn->dnsv4_fd, 1286 sendto (vpn->dnsv4_fd,
1272 send->pkt->at (0), send->pkt->len, 0, 1287 send->pkt->at (0), send->pkt->len, 0,
1273 vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ()); 1288 vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
1274 }
1275 } 1289 }
1276 else
1277 NEXT (last_sent + send_interval);
1278 1290
1279 slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d)", 1291 slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",
1280 poll_interval, send_interval, next - NOW, 1292 poll_interval, send_interval, next - NOW,
1281 vpn->dns_sndpq.size (), snddq.size ()); 1293 vpn->dns_sndpq.size (), snddq.size (),
1294 rcvpq.size ());
1282 1295
1283 // TODO: no idea when this happens, but when next < NOW, we have a problem 1296 // TODO: no idea when this happens, but when next < NOW, we have a problem
1297 // doesn't seem to happen anymore
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

Diff Legend

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