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Comparing gvpe/src/connection.C (file contents):
Revision 1.2 by pcg, Wed Apr 2 03:25:17 2003 UTC vs.
Revision 1.20 by pcg, Tue Oct 14 15:48:15 2003 UTC

35#include "slog.h" 35#include "slog.h"
36#include "device.h" 36#include "device.h"
37#include "vpn.h" 37#include "vpn.h"
38#include "connection.h" 38#include "connection.h"
39 39
40#include "netcompat.h"
41
40#if !HAVE_RAND_PSEUDO_BYTES 42#if !HAVE_RAND_PSEUDO_BYTES
41# define RAND_pseudo_bytes RAND_bytes 43# define RAND_pseudo_bytes RAND_bytes
42#endif 44#endif
43 45
44#define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic 46#define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic
85 rsachallenge chg; 87 rsachallenge chg;
86}; 88};
87 89
88struct rsa_cache : list<rsa_entry> 90struct rsa_cache : list<rsa_entry>
89{ 91{
90 void cleaner_cb (tstamp &ts); time_watcher cleaner; 92 void cleaner_cb (time_watcher &w); time_watcher cleaner;
91 93
92 bool find (const rsaid &id, rsachallenge &chg) 94 bool find (const rsaid &id, rsachallenge &chg)
93 { 95 {
94 for (iterator i = begin (); i != end (); ++i) 96 for (iterator i = begin (); i != end (); ++i)
95 { 97 {
129 : cleaner (this, &rsa_cache::cleaner_cb) 131 : cleaner (this, &rsa_cache::cleaner_cb)
130 { } 132 { }
131 133
132} rsa_cache; 134} rsa_cache;
133 135
134void rsa_cache::cleaner_cb (tstamp &ts) 136void rsa_cache::cleaner_cb (time_watcher &w)
135{ 137{
136 if (empty ()) 138 if (empty ())
137 ts = TSTAMP_CANCEL; 139 w.at = TSTAMP_CANCEL;
138 else 140 else
139 { 141 {
140 ts = NOW + RSA_TTL; 142 w.at = NOW + RSA_TTL;
141 143
142 for (iterator i = begin (); i != end (); ) 144 for (iterator i = begin (); i != end (); )
143 if (i->expire <= NOW) 145 if (i->expire <= NOW)
144 i = erase (i); 146 i = erase (i);
145 else 147 else
147 } 149 }
148} 150}
149 151
150////////////////////////////////////////////////////////////////////////////// 152//////////////////////////////////////////////////////////////////////////////
151 153
152void pkt_queue::put (tap_packet *p) 154void pkt_queue::put (net_packet *p)
153{ 155{
154 if (queue[i]) 156 if (queue[i])
155 { 157 {
156 delete queue[i]; 158 delete queue[i];
157 j = (j + 1) % QUEUEDEPTH; 159 j = (j + 1) % QUEUEDEPTH;
160 queue[i] = p; 162 queue[i] = p;
161 163
162 i = (i + 1) % QUEUEDEPTH; 164 i = (i + 1) % QUEUEDEPTH;
163} 165}
164 166
165tap_packet *pkt_queue::get () 167net_packet *pkt_queue::get ()
166{ 168{
167 tap_packet *p = queue[j]; 169 net_packet *p = queue[j];
168 170
169 if (p) 171 if (p)
170 { 172 {
171 queue[j] = 0; 173 queue[j] = 0;
172 j = (j + 1) % QUEUEDEPTH; 174 j = (j + 1) % QUEUEDEPTH;
197// only do action once every x seconds per host whole allowing bursts. 199// only do action once every x seconds per host whole allowing bursts.
198// this implementation ("splay list" ;) is inefficient, 200// this implementation ("splay list" ;) is inefficient,
199// but low on resources. 201// but low on resources.
200struct net_rate_limiter : list<net_rateinfo> 202struct net_rate_limiter : list<net_rateinfo>
201{ 203{
202 static const double ALPHA = 1. - 1. / 90.; // allow bursts 204 static const double ALPHA = 1. - 1. / 600.; // allow bursts
203 static const double CUTOFF = 20.; // one event every CUTOFF seconds 205 static const double CUTOFF = 10.; // one event every CUTOFF seconds
204 static const double EXPIRE = CUTOFF * 30.; // expire entries after this time 206 static const double EXPIRE = CUTOFF * 30.; // expire entries after this time
207 static const double MAXDIF = CUTOFF * (1. / (1. - ALPHA)); // maximum diff /count value
205 208
206 bool can (const sockinfo &si) { return can((u32)si.host); } 209 bool can (const sockinfo &si) { return can((u32)si.host); }
207 bool can (u32 host); 210 bool can (u32 host);
208}; 211};
209 212
210net_rate_limiter auth_rate_limiter, reset_rate_limiter; 213net_rate_limiter auth_rate_limiter, reset_rate_limiter;
211 214
225 { 228 {
226 net_rateinfo ri; 229 net_rateinfo ri;
227 230
228 ri.host = host; 231 ri.host = host;
229 ri.pcnt = 1.; 232 ri.pcnt = 1.;
230 ri.diff = CUTOFF * (1. / (1. - ALPHA)); 233 ri.diff = MAXDIF;
231 ri.last = NOW; 234 ri.last = NOW;
232 235
233 push_front (ri); 236 push_front (ri);
234 237
235 return true; 238 return true;
242 ri.pcnt = ri.pcnt * ALPHA; 245 ri.pcnt = ri.pcnt * ALPHA;
243 ri.diff = ri.diff * ALPHA + (NOW - ri.last); 246 ri.diff = ri.diff * ALPHA + (NOW - ri.last);
244 247
245 ri.last = NOW; 248 ri.last = NOW;
246 249
250 double dif = ri.diff / ri.pcnt;
251
247 bool send = ri.diff / ri.pcnt > CUTOFF; 252 bool send = dif > CUTOFF;
248 253
254 if (dif > MAXDIF)
255 {
256 ri.pcnt = 1.;
257 ri.diff = MAXDIF;
258 }
249 if (send) 259 else if (send)
250 ri.pcnt++; 260 ri.pcnt++;
251 261
252 push_front (ri); 262 push_front (ri);
253 263
254 return send; 264 return send;
285 hmac_gen (ctx); 295 hmac_gen (ctx);
286 296
287 return !memcmp (hmac, hmac_digest, HMACLENGTH); 297 return !memcmp (hmac, hmac_digest, HMACLENGTH);
288} 298}
289 299
290void vpn_packet::set_hdr (ptype type, unsigned int dst) 300void vpn_packet::set_hdr (ptype type_, unsigned int dst)
291{ 301{
292 this->type = type; 302 type = type_;
293 303
294 int src = THISNODE->id; 304 int src = THISNODE->id;
295 305
296 src1 = src; 306 src1 = src;
297 srcdst = ((src >> 8) << 4) | (dst >> 8); 307 srcdst = ((src >> 8) << 4) | (dst >> 8);
467 set_hdr (type, dst); 477 set_hdr (type, dst);
468} 478}
469 479
470bool config_packet::chk_config () const 480bool config_packet::chk_config () const
471{ 481{
472 return prot_major == PROTOCOL_MAJOR 482 if (prot_major != PROTOCOL_MAJOR)
473 && randsize == RAND_SIZE 483 slog (L_WARN, _("major version mismatch (%d <=> %d)"), prot_major, PROTOCOL_MAJOR);
474 && hmaclen == HMACLENGTH 484 else if (randsize != RAND_SIZE)
475 && flags == curflags () 485 slog (L_WARN, _("rand size mismatch (%d <=> %d)"), randsize, RAND_SIZE);
486 else if (hmaclen != HMACLENGTH)
487 slog (L_WARN, _("hmac length mismatch (%d <=> %d)"), hmaclen, HMACLENGTH);
488 else if (flags != curflags ())
489 slog (L_WARN, _("flag mismatch (%x <=> %x)"), flags, curflags ());
476 && challengelen == sizeof (rsachallenge) 490 else if (challengelen != sizeof (rsachallenge))
491 slog (L_WARN, _("challenge length mismatch (%d <=> %d)"), challengelen, sizeof (rsachallenge));
477 && cipher_nid == htonl (EVP_CIPHER_nid (CIPHER)) 492 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER)))
493 slog (L_WARN, _("cipher mismatch (%x <=> %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER));
478 && digest_nid == htonl (EVP_MD_type (RSA_HASH)) 494 else if (digest_nid != htonl (EVP_MD_type (RSA_HASH)))
495 slog (L_WARN, _("digest mismatch (%x <=> %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH));
479 && hmac_nid == htonl (EVP_MD_type (DIGEST)); 496 else if (hmac_nid != htonl (EVP_MD_type (DIGEST)))
497 slog (L_WARN, _("hmac mismatch (%x <=> %x)"), ntohl (hmac_nid), EVP_MD_type (DIGEST));
498 else
499 return true;
500
501 return false;
480} 502}
481 503
482struct auth_req_packet : config_packet 504struct auth_req_packet : config_packet
483{ 505{
484 char magic[8]; 506 char magic[8];
546}; 568};
547 569
548///////////////////////////////////////////////////////////////////////////// 570/////////////////////////////////////////////////////////////////////////////
549 571
550void 572void
573connection::connection_established ()
574{
575 if (ictx && octx)
576 {
577 connectmode = conf->connectmode;
578
579 rekey.start (NOW + ::conf.rekey);
580 keepalive.start (NOW + ::conf.keepalive);
581
582 // send queued packets
583 if (ictx && octx)
584 {
585 while (tap_packet *p = (tap_packet *)data_queue.get ())
586 {
587 send_data_packet (p);
588 delete p;
589 }
590
591 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ())
592 {
593 send_vpn_packet (p, si, IPTOS_RELIABILITY);
594 delete p;
595 }
596 }
597 }
598 else
599 {
600 retry_cnt = 0;
601 establish_connection.start (NOW + 5);
602 keepalive.reset ();
603 rekey.reset ();
604 }
605}
606
607void
551connection::reset_dstaddr () 608connection::reset_si ()
552{ 609{
553 si.set (conf);
554}
555
556void
557connection::send_ping (const sockinfo &si, u8 pong)
558{
559 ping_packet *pkt = new ping_packet;
560
561 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING);
562 send_vpn_packet (pkt, si, IPTOS_LOWDELAY);
563
564 delete pkt;
565}
566
567void
568connection::send_reset (const sockinfo &si)
569{
570 if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED)
571 {
572 config_packet *pkt = new config_packet;
573
574 pkt->setup (vpn_packet::PT_RESET, conf->id);
575 send_vpn_packet (pkt, si, IPTOS_MINCOST);
576
577 delete pkt;
578 }
579}
580
581void
582connection::send_auth_request (const sockinfo &si, bool initiate)
583{
584 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols);
585
586 protocol = best_protocol (THISNODE->protocols & conf->protocols); 610 protocol = best_protocol (THISNODE->protocols & conf->protocols);
587 611
588 // mask out protocols we cannot establish 612 // mask out protocols we cannot establish
589 if (!conf->udp_port) protocol &= ~PROT_UDPv4; 613 if (!conf->udp_port) protocol &= ~PROT_UDPv4;
590 if (!conf->tcp_port) protocol &= ~PROT_TCPv4; 614 if (!conf->tcp_port) protocol &= ~PROT_TCPv4;
591 615
592 if (protocol) 616 si.set (conf, protocol);
617}
618
619// ensure sockinfo is valid, forward if necessary
620const sockinfo &
621connection::forward_si (const sockinfo &si) const
622{
623 if (!si.valid ())
624 {
625 connection *r = vpn->find_router ();
626
627 if (r)
628 {
629 slog (L_DEBUG, _("%s: no common protocol, trying indirectly through %s"),
630 conf->nodename, r->conf->nodename);
631 return r->si;
632 }
633 else
634 slog (L_DEBUG, _("%s: node unreachable, no common protocol"),
635 conf->nodename);
593 { 636 }
594 rsachallenge chg;
595 637
596 rsa_cache.gen (pkt->id, chg); 638 return si;
639}
597 640
598 if (0 > RSA_public_encrypt (sizeof chg, 641void
599 (unsigned char *)&chg, (unsigned char *)&pkt->encr, 642connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos)
600 conf->rsa_key, RSA_PKCS1_OAEP_PADDING)) 643{
601 fatal ("RSA_public_encrypt error"); 644 if (!vpn->send_vpn_packet (pkt, si, tos))
645 reset_connection ();
646}
602 647
603 slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)si); 648void
649connection::send_ping (const sockinfo &si, u8 pong)
650{
651 ping_packet *pkt = new ping_packet;
604 652
605 send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly 653 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING);
654 send_vpn_packet (pkt, si, IPTOS_LOWDELAY);
655
656 delete pkt;
657}
658
659void
660connection::send_reset (const sockinfo &si)
661{
662 if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED)
663 {
664 config_packet *pkt = new config_packet;
665
666 pkt->setup (vpn_packet::PT_RESET, conf->id);
667 send_vpn_packet (pkt, si, IPTOS_MINCOST);
606 668
607 delete pkt; 669 delete pkt;
608 } 670 }
609 else 671}
610 ; // silently fail 672
673void
674connection::send_auth_request (const sockinfo &si, bool initiate)
675{
676 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols);
677
678 rsachallenge chg;
679
680 rsa_cache.gen (pkt->id, chg);
681
682 if (0 > RSA_public_encrypt (sizeof chg,
683 (unsigned char *)&chg, (unsigned char *)&pkt->encr,
684 conf->rsa_key, RSA_PKCS1_OAEP_PADDING))
685 fatal ("RSA_public_encrypt error");
686
687 slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)si);
688
689 send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly
690
691 delete pkt;
611} 692}
612 693
613void 694void
614connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg) 695connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg)
615{ 696{
641 722
642 delete r; 723 delete r;
643} 724}
644 725
645void 726void
646connection::establish_connection_cb (tstamp &ts) 727connection::establish_connection_cb (time_watcher &w)
647{ 728{
648 if (ictx || conf == THISNODE 729 if (ictx || conf == THISNODE
649 || connectmode == conf_node::C_NEVER 730 || connectmode == conf_node::C_NEVER
650 || connectmode == conf_node::C_DISABLED) 731 || connectmode == conf_node::C_DISABLED)
651 ts = TSTAMP_CANCEL; 732 w.at = TSTAMP_CANCEL;
652 else if (ts <= NOW) 733 else if (w.at <= NOW)
653 { 734 {
654 double retry_int = double (retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2)) * 0.6; 735 double retry_int = double (retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2)) * 0.6;
655 736
656 if (retry_int < 3600 * 8) 737 if (retry_int < 3600 * 8)
657 retry_cnt++; 738 retry_cnt++;
658 739
659 ts = NOW + retry_int; 740 w.at = NOW + retry_int;
660 741
661 if (conf->hostname) 742 reset_si ();
743
744 if (si.prot && !si.host)
745 vpn->send_connect_request (conf->id);
746 else
662 { 747 {
663 reset_dstaddr (); 748 const sockinfo &dsi = forward_si (si);
749
664 if (si.host && auth_rate_limiter.can (si)) 750 if (dsi.valid () && auth_rate_limiter.can (dsi))
665 { 751 {
666 if (retry_cnt < 4) 752 if (retry_cnt < 4)
667 send_auth_request (si, true); 753 send_auth_request (dsi, true);
668 else 754 else
669 send_ping (si, 0); 755 send_ping (dsi, 0);
670 } 756 }
671 } 757 }
672 else
673 vpn->connect_request (conf->id);
674 } 758 }
675} 759}
676 760
677void 761void
678connection::reset_connection () 762connection::reset_connection ()
707 791
708 reset_connection (); 792 reset_connection ();
709} 793}
710 794
711void 795void
712connection::rekey_cb (tstamp &ts) 796connection::rekey_cb (time_watcher &w)
713{ 797{
714 ts = TSTAMP_CANCEL; 798 w.at = TSTAMP_CANCEL;
715 799
716 reset_connection (); 800 reset_connection ();
717 establish_connection (); 801 establish_connection ();
718} 802}
719 803
721connection::send_data_packet (tap_packet *pkt, bool broadcast) 805connection::send_data_packet (tap_packet *pkt, bool broadcast)
722{ 806{
723 vpndata_packet *p = new vpndata_packet; 807 vpndata_packet *p = new vpndata_packet;
724 int tos = 0; 808 int tos = 0;
725 809
810 // I am not hilarious about peeking into packets, but so be it.
726 if (conf->inherit_tos 811 if (conf->inherit_tos
727 && (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP 812 && (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP
728 && ((*pkt)[14] & 0xf0) == 0x40) // IPv4 813 && ((*pkt)[14] & 0xf0) == 0x40) // IPv4
729 tos = (*pkt)[15] & IPTOS_TOS_MASK; 814 tos = (*pkt)[15] & IPTOS_TOS_MASK;
730 815
743 if (ictx && octx) 828 if (ictx && octx)
744 send_data_packet (pkt, broadcast); 829 send_data_packet (pkt, broadcast);
745 else 830 else
746 { 831 {
747 if (!broadcast)//DDDD 832 if (!broadcast)//DDDD
748 queue.put (new tap_packet (*pkt)); 833 data_queue.put (new tap_packet (*pkt));
834
835 establish_connection ();
836 }
837}
838
839void connection::inject_vpn_packet (vpn_packet *pkt, int tos)
840{
841 if (ictx && octx)
842 send_vpn_packet (pkt, si, tos);
843 else
844 {
845 vpn_queue.put (new vpn_packet (*pkt));
749 846
750 establish_connection (); 847 establish_connection ();
751 } 848 }
752} 849}
753 850
759 slog (L_NOISE, "<<%d received packet type %d from %d to %d", 856 slog (L_NOISE, "<<%d received packet type %d from %d to %d",
760 conf->id, pkt->typ (), pkt->src (), pkt->dst ()); 857 conf->id, pkt->typ (), pkt->src (), pkt->dst ());
761 858
762 switch (pkt->typ ()) 859 switch (pkt->typ ())
763 { 860 {
764 case vpn_packet::PT_PING: 861 case vpn_packet::PT_PING:
765 // we send pings instead of auth packets after some retries, 862 // we send pings instead of auth packets after some retries,
766 // so reset the retry counter and establish a connection 863 // so reset the retry counter and establish a connection
767 // when we receive a ping. 864 // when we receive a ping.
768 if (!ictx) 865 if (!ictx)
866 {
867 if (auth_rate_limiter.can (rsi))
868 send_auth_request (rsi, true);
869 }
870 else
871 send_ping (rsi, 1); // pong
872
873 break;
874
875 case vpn_packet::PT_PONG:
876 break;
877
878 case vpn_packet::PT_RESET:
769 { 879 {
770 if (auth_rate_limiter.can (rsi)) 880 reset_connection ();
771 send_auth_request (rsi, true); 881
882 config_packet *p = (config_packet *) pkt;
883
884 if (!p->chk_config ())
885 {
886 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"),
887 conf->nodename, (const char *)rsi);
888 connectmode = conf_node::C_DISABLED;
889 }
890 else if (connectmode == conf_node::C_ALWAYS)
891 establish_connection ();
772 } 892 }
773 else
774 send_ping (rsi, 1); // pong
775
776 break; 893 break;
777 894
778 case vpn_packet::PT_PONG:
779 break;
780
781 case vpn_packet::PT_RESET: 895 case vpn_packet::PT_AUTH_REQ:
782 { 896 if (auth_rate_limiter.can (rsi))
783 reset_connection ();
784
785 config_packet *p = (config_packet *) pkt;
786
787 if (!p->chk_config ())
788 { 897 {
898 auth_req_packet *p = (auth_req_packet *) pkt;
899
900 slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate);
901
902 if (p->chk_config () && !strncmp (p->magic, MAGIC, 8))
903 {
904 if (p->prot_minor != PROTOCOL_MINOR)
905 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
906 conf->nodename, (const char *)rsi,
907 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
908
909 if (p->initiate)
910 send_auth_request (rsi, false);
911
912 rsachallenge k;
913
914 if (0 > RSA_private_decrypt (sizeof (p->encr),
915 (unsigned char *)&p->encr, (unsigned char *)&k,
916 ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING))
917 slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"),
918 conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0));
919 else
920 {
921 delete octx;
922
923 octx = new crypto_ctx (k, 1);
924 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff;
925
926 conf->protocols = p->protocols;
927
928 send_auth_response (rsi, p->id, k);
929
930 connection_established ();
931
932 break;
933 }
934 }
935 else
789 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"), 936 slog (L_WARN, _("%s(%s): protocol mismatch"),
790 conf->nodename, (const char *)rsi); 937 conf->nodename, (const char *)rsi);
791 connectmode = conf_node::C_DISABLED; 938
939 send_reset (rsi);
792 } 940 }
793 else if (connectmode == conf_node::C_ALWAYS) 941
794 establish_connection ();
795 }
796 break; 942 break;
797 943
798 case vpn_packet::PT_AUTH_REQ: 944 case vpn_packet::PT_AUTH_RES:
799 if (auth_rate_limiter.can (rsi))
800 { 945 {
801 auth_req_packet *p = (auth_req_packet *) pkt; 946 auth_res_packet *p = (auth_res_packet *) pkt;
802 947
803 slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate); 948 slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id);
804 949
805 if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) 950 if (p->chk_config ())
806 { 951 {
807 if (p->prot_minor != PROTOCOL_MINOR) 952 if (p->prot_minor != PROTOCOL_MINOR)
808 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), 953 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
809 conf->nodename, (const char *)rsi, 954 conf->nodename, (const char *)rsi,
810 PROTOCOL_MINOR, conf->nodename, p->prot_minor); 955 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
811 956
812 if (p->initiate)
813 send_auth_request (rsi, false);
814
815 rsachallenge k; 957 rsachallenge chg;
816 958
817 if (0 > RSA_private_decrypt (sizeof (p->encr), 959 if (!rsa_cache.find (p->id, chg))
818 (unsigned char *)&p->encr, (unsigned char *)&k, 960 {
819 ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) 961 slog (L_ERR, _("%s(%s): unrequested auth response ignored"),
820 slog (L_ERR, _("%s(%s): challenge illegal or corrupted"),
821 conf->nodename, (const char *)rsi); 962 conf->nodename, (const char *)rsi);
963 break;
964 }
822 else 965 else
823 { 966 {
824 retry_cnt = 0; 967 crypto_ctx *cctx = new crypto_ctx (chg, 0);
825 establish_connection.set (NOW + 8); //? ;) 968
826 keepalive.reset (); 969 if (!p->hmac_chk (cctx))
970 {
971 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n"
972 "could be an attack, or just corruption or an synchronization error"),
973 conf->nodename, (const char *)rsi);
974 break;
975 }
827 rekey.reset (); 976 else
977 {
978 rsaresponse h;
828 979
980 rsa_hash (p->id, chg, h);
981
982 if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h))
983 {
984 prot_minor = p->prot_minor;
985
986 delete ictx; ictx = cctx;
987
988 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
989
990 si = rsi;
991 protocol = rsi.prot;
992
993 connection_established ();
994
995 slog (L_INFO, _("%s(%s): connection established, protocol version %d.%d"),
996 conf->nodename, (const char *)rsi,
997 p->prot_major, p->prot_minor);
998
999 if (::conf.script_node_up)
1000 run_script (run_script_cb (this, &connection::script_node_up), false);
1001
1002 break;
1003 }
1004 else
1005 slog (L_ERR, _("%s(%s): sent and received challenge do not match"),
1006 conf->nodename, (const char *)rsi);
1007 }
1008
829 delete ictx; 1009 delete cctx;
830 ictx = 0;
831
832 delete octx;
833
834 octx = new crypto_ctx (k, 1);
835 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff;
836
837 conf->protocols = p->protocols;
838 send_auth_response (rsi, p->id, k);
839
840 break;
841 } 1010 }
842 } 1011 }
843
844 send_reset (rsi);
845 } 1012 }
846 1013
1014 send_reset (rsi);
847 break; 1015 break;
848 1016
849 case vpn_packet::PT_AUTH_RES: 1017 case vpn_packet::PT_DATA_COMPRESSED:
850 { 1018#if !ENABLE_COMPRESSION
851 auth_res_packet *p = (auth_res_packet *) pkt; 1019 send_reset (rsi);
1020 break;
1021#endif
852 1022
853 slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id); 1023 case vpn_packet::PT_DATA_UNCOMPRESSED:
854 1024
855 if (p->chk_config ()) 1025 if (ictx && octx)
856 { 1026 {
857 if (p->prot_minor != PROTOCOL_MINOR) 1027 vpndata_packet *p = (vpndata_packet *)pkt;
858 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
859 conf->nodename, (const char *)rsi,
860 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
861 1028
862 rsachallenge chg; 1029 if (!p->hmac_chk (ictx))
863 1030 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n"
864 if (!rsa_cache.find (p->id, chg)) 1031 "could be an attack, or just corruption or an synchronization error"),
865 slog (L_ERR, _("%s(%s): unrequested auth response"),
866 conf->nodename, (const char *)rsi); 1032 conf->nodename, (const char *)rsi);
867 else 1033 else
868 { 1034 {
869 crypto_ctx *cctx = new crypto_ctx (chg, 0);
870
871 if (!p->hmac_chk (cctx))
872 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n"
873 "could be an attack, or just corruption or an synchronization error"),
874 conf->nodename, (const char *)rsi);
875 else 1035 u32 seqno;
1036 tap_packet *d = p->unpack (this, seqno);
1037
1038 if (iseqno.recv_ok (seqno))
876 { 1039 {
877 rsaresponse h; 1040 vpn->tap->send (d);
878 1041
879 rsa_hash (p->id, chg, h); 1042 if (p->dst () == 0) // re-broadcast
1043 for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i)
1044 {
1045 connection *c = *i;
880 1046
881 if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) 1047 if (c->conf != THISNODE && c->conf != conf)
1048 c->inject_data_packet (d);
1049 }
1050
1051 if (si != rsi)
882 { 1052 {
883 prot_minor = p->prot_minor; 1053 // fast re-sync on connection changes, useful especially for tcp/ip
884
885 delete ictx; ictx = cctx;
886
887 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
888
889 si = rsi; 1054 si = rsi;
890 1055
891 rekey.set (NOW + ::conf.rekey); 1056 slog (L_INFO, _("%s(%s): socket address changed to %s"),
892 keepalive.set (NOW + ::conf.keepalive);
893
894 // send queued packets
895 while (tap_packet *p = queue.get ())
896 {
897 send_data_packet (p);
898 delete p;
899 }
900
901 connectmode = conf->connectmode;
902
903 slog (L_INFO, _("%s(%s): %s connection established, protocol version %d.%d"),
904 conf->nodename, (const char *)rsi, 1057 conf->nodename, (const char *)si, (const char *)rsi);
905 strprotocol (protocol),
906 p->prot_major, p->prot_minor);
907
908 if (::conf.script_node_up)
909 run_script (run_script_cb (this, &connection::script_node_up), false);
910
911 break;
912 } 1058 }
1059
913 else 1060 delete d;
914 slog (L_ERR, _("%s(%s): sent and received challenge do not match"), 1061
915 conf->nodename, (const char *)rsi); 1062 break;
916 } 1063 }
917
918 delete cctx;
919 } 1064 }
920 } 1065 }
921 }
922 1066
923 send_reset (rsi); 1067 send_reset (rsi);
924 break; 1068 break;
925 1069
926 case vpn_packet::PT_DATA_COMPRESSED:
927#if !ENABLE_COMPRESSION
928 send_reset (rsi);
929 break;
930#endif
931
932 case vpn_packet::PT_DATA_UNCOMPRESSED:
933
934 if (ictx && octx)
935 {
936 vpndata_packet *p = (vpndata_packet *)pkt;
937
938 if (rsi == si)
939 {
940 if (!p->hmac_chk (ictx))
941 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n"
942 "could be an attack, or just corruption or an synchronization error"),
943 conf->nodename, (const char *)rsi);
944 else
945 {
946 u32 seqno;
947 tap_packet *d = p->unpack (this, seqno);
948
949 if (iseqno.recv_ok (seqno))
950 {
951 vpn->tap->send (d);
952
953 if (p->dst () == 0) // re-broadcast
954 for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i)
955 {
956 connection *c = *i;
957
958 if (c->conf != THISNODE && c->conf != conf)
959 c->inject_data_packet (d);
960 }
961
962 delete d;
963
964 break;
965 }
966 }
967 }
968 else
969 slog (L_ERR, _("received data packet from unknown source %s"), (const char *)rsi);
970 }
971
972 send_reset (rsi);
973 break;
974
975 case vpn_packet::PT_CONNECT_REQ: 1070 case vpn_packet::PT_CONNECT_REQ:
976 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) 1071 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx))
977 { 1072 {
978 connect_req_packet *p = (connect_req_packet *) pkt; 1073 connect_req_packet *p = (connect_req_packet *) pkt;
979 1074
980 assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything 1075 assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything
981 conf->protocols = p->protocols;
982 connection *c = vpn->conns[p->id - 1]; 1076 connection *c = vpn->conns[p->id - 1];
1077 conf->protocols = p->protocols;
983 1078
984 slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n", 1079 slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n",
985 conf->id, p->id, c->ictx && c->octx); 1080 conf->id, p->id, c->ictx && c->octx);
986 1081
987 if (c->ictx && c->octx) 1082 if (c->ictx && c->octx)
988 { 1083 {
989 // send connect_info packets to both sides, in case one is 1084 // send connect_info packets to both sides, in case one is
990 // behind a nat firewall (or both ;) 1085 // behind a nat firewall (or both ;)
991 c->send_connect_info (conf->id, si, conf->protocols); 1086 c->send_connect_info (conf->id, si, conf->protocols);
992 send_connect_info (c->conf->id, c->si, c->conf->protocols); 1087 send_connect_info (c->conf->id, c->si, c->conf->protocols);
993 } 1088 }
1089 else
1090 c->establish_connection ();
994 } 1091 }
995 1092
996 break; 1093 break;
997 1094
998 case vpn_packet::PT_CONNECT_INFO: 1095 case vpn_packet::PT_CONNECT_INFO:
999 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) 1096 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx))
1000 { 1097 {
1001 connect_info_packet *p = (connect_info_packet *) pkt; 1098 connect_info_packet *p = (connect_info_packet *) pkt;
1002 1099
1003 assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything 1100 assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything
1004 conf->protocols = p->protocols; 1101
1005 connection *c = vpn->conns[p->id - 1]; 1102 connection *c = vpn->conns[p->id - 1];
1006 1103
1104 c->conf->protocols = p->protocols;
1105 protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf));
1106 p->si.upgrade_protocol (protocol, c->conf);
1107
1007 slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)", 1108 slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)",
1008 conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx); 1109 conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx);
1009 1110
1111 const sockinfo &dsi = forward_si (p->si);
1112
1113 if (dsi.valid ())
1010 c->send_auth_request (p->si, true); 1114 c->send_auth_request (dsi, true);
1011 } 1115 }
1012 1116
1013 break; 1117 break;
1014 1118
1015 default: 1119 default:
1016 send_reset (rsi); 1120 send_reset (rsi);
1017 break; 1121 break;
1018
1019 } 1122 }
1020} 1123}
1021 1124
1022void connection::keepalive_cb (tstamp &ts) 1125void connection::keepalive_cb (time_watcher &w)
1023{ 1126{
1024 if (NOW >= last_activity + ::conf.keepalive + 30) 1127 if (NOW >= last_activity + ::conf.keepalive + 30)
1025 { 1128 {
1026 reset_connection (); 1129 reset_connection ();
1027 establish_connection (); 1130 establish_connection ();
1028 } 1131 }
1029 else if (NOW < last_activity + ::conf.keepalive) 1132 else if (NOW < last_activity + ::conf.keepalive)
1030 ts = last_activity + ::conf.keepalive; 1133 w.at = last_activity + ::conf.keepalive;
1031 else if (conf->connectmode != conf_node::C_ONDEMAND 1134 else if (conf->connectmode != conf_node::C_ONDEMAND
1032 || THISNODE->connectmode != conf_node::C_ONDEMAND) 1135 || THISNODE->connectmode != conf_node::C_ONDEMAND)
1033 { 1136 {
1034 send_ping (si); 1137 send_ping (si);
1035 ts = NOW + 5; 1138 w.at = NOW + 5;
1036 } 1139 }
1140 else if (NOW < last_activity + ::conf.keepalive + 10)
1141 // hold ondemand connections implicitly a few seconds longer
1142 // should delete octx, though, or something like that ;)
1143 w.at = last_activity + ::conf.keepalive + 10;
1037 else 1144 else
1038 reset_connection (); 1145 reset_connection ();
1039} 1146}
1040 1147
1041void connection::connect_request (int id) 1148void connection::send_connect_request (int id)
1042{ 1149{
1043 connect_req_packet *p = new connect_req_packet (conf->id, id, conf->protocols); 1150 connect_req_packet *p = new connect_req_packet (conf->id, id, conf->protocols);
1044 1151
1045 slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", conf->id, id); 1152 slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", conf->id, id);
1046 p->hmac_set (octx); 1153 p->hmac_set (octx);
1049 delete p; 1156 delete p;
1050} 1157}
1051 1158
1052void connection::script_node () 1159void connection::script_node ()
1053{ 1160{
1054 vpn->script_if_up (0); 1161 vpn->script_if_up ();
1055 1162
1056 char *env; 1163 char *env;
1057 asprintf (&env, "DESTID=%d", conf->id); putenv (env); 1164 asprintf (&env, "DESTID=%d", conf->id); putenv (env);
1058 asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); 1165 asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env);
1059 asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); 1166 asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env);
1060 asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); 1167 asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env);
1061} 1168}
1062 1169
1063const char *connection::script_node_up (int) 1170const char *connection::script_node_up ()
1064{ 1171{
1065 script_node (); 1172 script_node ();
1066 1173
1067 putenv ("STATE=up"); 1174 putenv ("STATE=up");
1068 1175
1069 return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; 1176 return ::conf.script_node_up ? ::conf.script_node_up : "node-up";
1070} 1177}
1071 1178
1072const char *connection::script_node_down (int) 1179const char *connection::script_node_down ()
1073{ 1180{
1074 script_node (); 1181 script_node ();
1075 1182
1076 putenv ("STATE=down"); 1183 putenv ("STATE=down");
1077 1184
1078 return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; 1185 return ::conf.script_node_up ? ::conf.script_node_down : "node-down";
1079}
1080
1081// send a vpn packet out to other hosts
1082void
1083connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos)
1084{
1085 if (protocol & PROT_IPv4)
1086 vpn->send_ipv4_packet (pkt, si, tos);
1087 else
1088 vpn->send_udpv4_packet (pkt, si, tos);
1089} 1186}
1090 1187
1091connection::connection(struct vpn *vpn_) 1188connection::connection(struct vpn *vpn_)
1092: vpn(vpn_) 1189: vpn(vpn_)
1093, rekey (this, &connection::rekey_cb) 1190, rekey (this, &connection::rekey_cb)

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