… | |
… | |
356 | return true; |
356 | return true; |
357 | } |
357 | } |
358 | |
358 | |
359 | vpn_packet *byte_stream::get () |
359 | vpn_packet *byte_stream::get () |
360 | { |
360 | { |
|
|
361 | unsigned int len; |
|
|
362 | |
|
|
363 | for (;;) |
|
|
364 | { |
361 | unsigned int len = (data [0] << 8) | data [1]; |
365 | len = (data [0] << 8) | data [1]; |
362 | |
366 | |
363 | if (len > MAXSIZE && fill >= 2) |
367 | if (len <= MAXSIZE || fill < 2) |
364 | assert (len <= MAXSIZE || fill < 2); // TODO handle this gracefully, connection reset |
368 | break; |
365 | |
369 | |
|
|
370 | // TODO: handle this better than skipping, e.g. by reset |
|
|
371 | slog (L_DEBUG, _("DNS: corrupted packet stream skipping a byte...")); |
|
|
372 | remove (1); |
|
|
373 | } |
|
|
374 | |
366 | if (fill < len + 2) |
375 | if (fill < len + 2) |
367 | return 0; |
376 | return 0; |
368 | |
377 | |
369 | vpn_packet *pkt = new vpn_packet; |
378 | vpn_packet *pkt = new vpn_packet; |
370 | |
379 | |
… | |
… | |
498 | return data - orig; |
507 | return data - orig; |
499 | } |
508 | } |
500 | |
509 | |
501 | ///////////////////////////////////////////////////////////////////////////// |
510 | ///////////////////////////////////////////////////////////////////////////// |
502 | |
511 | |
|
|
512 | static u16 dns_id = 0; // TODO: should be per-vpn |
|
|
513 | |
|
|
514 | static u16 next_id () |
|
|
515 | { |
|
|
516 | if (!dns_id) |
|
|
517 | dns_id = time (0); |
|
|
518 | |
|
|
519 | // the simplest lsfr with periodicity 65535 i could find |
|
|
520 | dns_id = (dns_id << 1) |
|
|
521 | | (((dns_id >> 1) |
|
|
522 | ^ (dns_id >> 2) |
|
|
523 | ^ (dns_id >> 4) |
|
|
524 | ^ (dns_id >> 15)) & 1); |
|
|
525 | |
|
|
526 | return dns_id; |
|
|
527 | } |
|
|
528 | |
|
|
529 | struct dns_rcv; |
|
|
530 | struct dns_snd; |
|
|
531 | |
|
|
532 | struct dns_connection |
|
|
533 | { |
|
|
534 | connection *c; |
|
|
535 | struct vpn *vpn; |
|
|
536 | |
|
|
537 | dns_cfg cfg; |
|
|
538 | |
|
|
539 | bool established; |
|
|
540 | |
|
|
541 | tstamp last_received; |
|
|
542 | tstamp last_sent; |
|
|
543 | double last_latency; |
|
|
544 | double poll_interval, send_interval; |
|
|
545 | |
|
|
546 | vector<dns_rcv *> rcvpq; |
|
|
547 | |
|
|
548 | byte_stream rcvdq; int rcvseq; |
|
|
549 | byte_stream snddq; int sndseq; |
|
|
550 | |
|
|
551 | void time_cb (time_watcher &w); time_watcher tw; |
|
|
552 | void receive_rep (dns_rcv *r); |
|
|
553 | |
|
|
554 | dns_connection (connection *c); |
|
|
555 | ~dns_connection (); |
|
|
556 | }; |
|
|
557 | |
503 | struct dns_snd |
558 | struct dns_snd |
504 | { |
559 | { |
505 | dns_packet *pkt; |
560 | dns_packet *pkt; |
506 | tstamp timeout, sent; |
561 | tstamp timeout, sent; |
507 | int retry; |
562 | int retry; |
508 | struct dns_connection *dns; |
563 | struct dns_connection *dns; |
509 | int seqno; |
564 | int seqno; |
510 | bool stdhdr; |
565 | bool stdhdr; |
511 | |
566 | |
512 | void gen_stream_req (int seqno, byte_stream &stream); |
567 | void gen_stream_req (int seqno, byte_stream &stream); |
513 | void gen_syn_req (const dns_cfg &cfg); |
568 | void gen_syn_req (); |
514 | |
569 | |
515 | dns_snd (dns_connection *dns); |
570 | dns_snd (dns_connection *dns); |
516 | ~dns_snd (); |
571 | ~dns_snd (); |
517 | }; |
572 | }; |
518 | |
|
|
519 | static u16 dns_id = 12098; // TODO: should be per-vpn |
|
|
520 | |
|
|
521 | static u16 next_id () |
|
|
522 | { |
|
|
523 | // the simplest lsfr with periodicity 65535 i could find |
|
|
524 | dns_id = (dns_id << 1) |
|
|
525 | | (((dns_id >> 1) |
|
|
526 | ^ (dns_id >> 2) |
|
|
527 | ^ (dns_id >> 4) |
|
|
528 | ^ (dns_id >> 15)) & 1); |
|
|
529 | |
|
|
530 | return dns_id; |
|
|
531 | } |
|
|
532 | |
573 | |
533 | dns_snd::dns_snd (dns_connection *dns) |
574 | dns_snd::dns_snd (dns_connection *dns) |
534 | : dns (dns) |
575 | : dns (dns) |
535 | { |
576 | { |
536 | timeout = 0; |
577 | timeout = 0; |
… | |
… | |
618 | (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN; |
659 | (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN; |
619 | |
660 | |
620 | pkt->len = offs; |
661 | pkt->len = offs; |
621 | } |
662 | } |
622 | |
663 | |
623 | void dns_snd::gen_syn_req (const dns_cfg &cfg) |
664 | void dns_snd::gen_syn_req () |
624 | { |
665 | { |
625 | timeout = NOW + INITIAL_SYN_TIMEOUT; |
666 | timeout = NOW + INITIAL_SYN_TIMEOUT; |
|
|
667 | |
|
|
668 | printf ("send syn\n");//D |
626 | |
669 | |
627 | pkt->flags = htons (DEFAULT_CLIENT_FLAGS); |
670 | pkt->flags = htons (DEFAULT_CLIENT_FLAGS); |
628 | pkt->qdcount = htons (1); |
671 | pkt->qdcount = htons (1); |
629 | |
672 | |
630 | int offs = 6*2; |
673 | int offs = 6 * 2; |
631 | |
674 | |
632 | int elen = cdc26.encode ((char *)pkt->at (offs + 1), (u8 *)&cfg, sizeof (dns_cfg)); |
675 | int elen = cdc26.encode ((char *)pkt->at (offs + 1), (u8 *)&dns->cfg, sizeof (dns_cfg)); |
633 | |
676 | |
634 | assert (elen <= MAX_LBL_SIZE); |
677 | assert (elen <= MAX_LBL_SIZE); |
635 | |
678 | |
636 | (*pkt)[offs] = elen; |
679 | (*pkt)[offs] = elen; |
637 | offs += elen + 1; |
680 | offs += elen + 1; |
… | |
… | |
666 | delete pkt; |
709 | delete pkt; |
667 | } |
710 | } |
668 | |
711 | |
669 | ///////////////////////////////////////////////////////////////////////////// |
712 | ///////////////////////////////////////////////////////////////////////////// |
670 | |
713 | |
671 | struct dns_connection |
|
|
672 | { |
|
|
673 | connection *c; |
|
|
674 | struct vpn *vpn; |
|
|
675 | |
|
|
676 | dns_cfg cfg; |
|
|
677 | |
|
|
678 | bool established; |
|
|
679 | |
|
|
680 | tstamp last_received; |
|
|
681 | tstamp last_sent; |
|
|
682 | double last_latency; |
|
|
683 | double poll_interval, send_interval; |
|
|
684 | |
|
|
685 | vector<dns_rcv *> rcvpq; |
|
|
686 | |
|
|
687 | byte_stream rcvdq; int rcvseq; |
|
|
688 | byte_stream snddq; int sndseq; |
|
|
689 | |
|
|
690 | void time_cb (time_watcher &w); time_watcher tw; |
|
|
691 | void receive_rep (dns_rcv *r); |
|
|
692 | |
|
|
693 | dns_connection (connection *c); |
|
|
694 | ~dns_connection (); |
|
|
695 | }; |
|
|
696 | |
|
|
697 | dns_connection::dns_connection (connection *c) |
714 | dns_connection::dns_connection (connection *c) |
698 | : c (c) |
715 | : c (c) |
699 | , rcvdq (MAX_BACKLOG * 2) |
716 | , rcvdq (MAX_BACKLOG * 2) |
700 | , snddq (MAX_BACKLOG * 2) |
717 | , snddq (MAX_BACKLOG * 2) |
701 | , tw (this, &dns_connection::time_cb) |
718 | , tw (this, &dns_connection::time_cb) |
… | |
… | |
765 | } |
782 | } |
766 | |
783 | |
767 | while (vpn_packet *pkt = rcvdq.get ()) |
784 | while (vpn_packet *pkt = rcvdq.get ()) |
768 | { |
785 | { |
769 | sockinfo si; |
786 | sockinfo si; |
770 | si.host = 0; si.port = 0; si.prot = PROT_DNSv4; |
787 | si.host = 0x01010101; si.port = htons (c->conf->id); si.prot = PROT_DNSv4; |
771 | |
788 | |
772 | vpn->recv_vpn_packet (pkt, si); |
789 | vpn->recv_vpn_packet (pkt, si); |
773 | |
790 | |
774 | delete pkt; |
791 | delete pkt; |
775 | } |
792 | } |
… | |
… | |
1142 | } |
1159 | } |
1143 | } |
1160 | } |
1144 | } |
1161 | } |
1145 | |
1162 | |
1146 | bool |
1163 | bool |
1147 | connection::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
1164 | vpn::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
1148 | { |
1165 | { |
|
|
1166 | int client = ntohs (si.port); |
|
|
1167 | |
|
|
1168 | assert (0 < client && client <= conns.size ()); |
|
|
1169 | |
|
|
1170 | connection *c = conns [client - 1]; |
|
|
1171 | |
1149 | if (!dns) |
1172 | if (!c->dns) |
1150 | dns = new dns_connection (this); |
1173 | c->dns = new dns_connection (c); |
1151 | |
1174 | |
1152 | if (!dns->snddq.put (pkt)) |
1175 | if (!c->dns->snddq.put (pkt)) |
1153 | return false; |
1176 | return false; |
1154 | |
1177 | |
1155 | dns->tw.trigger (); |
1178 | c->dns->tw.trigger (); |
1156 | |
1179 | |
1157 | return true; |
1180 | return true; |
1158 | } |
1181 | } |
1159 | |
1182 | |
1160 | void |
1183 | void |
… | |
… | |
1214 | { |
1237 | { |
1215 | if (vpn->dns_sndpq.empty ()) |
1238 | if (vpn->dns_sndpq.empty ()) |
1216 | { |
1239 | { |
1217 | send = new dns_snd (this); |
1240 | send = new dns_snd (this); |
1218 | |
1241 | |
|
|
1242 | printf ("new conn %p %d\n", this, c->conf->id);//D |
1219 | cfg.reset (THISNODE->id); |
1243 | cfg.reset (THISNODE->id); |
1220 | send->gen_syn_req (cfg); |
1244 | send->gen_syn_req (); |
1221 | } |
1245 | } |
1222 | } |
1246 | } |
1223 | else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING |
1247 | else if (vpn->dns_sndpq.size () < MAX_OUTSTANDING |
1224 | && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1))) |
1248 | && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1))) |
1225 | { |
1249 | { |
|
|
1250 | //printf ("sending data request etc.\n"); //D |
1226 | if (!snddq.empty ()) |
1251 | if (!snddq.empty ()) |
1227 | { |
1252 | { |
1228 | poll_interval = send_interval; |
1253 | poll_interval = send_interval; |
1229 | NEXT (NOW + send_interval); |
1254 | NEXT (NOW + send_interval); |
1230 | } |
1255 | } |