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Comparing gvpe/src/connection.C (file contents):
Revision 1.46 by pcg, Sat Mar 5 19:13:15 2005 UTC vs.
Revision 1.78 by pcg, Mon Aug 11 16:44:47 2008 UTC

1/* 1/*
2 connection.C -- manage a single connection 2 connection.C -- manage a single connection
3 Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de> 3 Copyright (C) 2003-2008 Marc Lehmann <gvpe@schmorp.de>
4 4
5 This file is part of GVPE. 5 This file is part of GVPE.
6 6
7 GVPE is free software; you can redistribute it and/or modify 7 GVPE is free software; you can redistribute it and/or modify it
8 it under the terms of the GNU General Public License as published by 8 under the terms of the GNU General Public License as published by the
9 the Free Software Foundation; either version 2 of the License, or 9 Free Software Foundation; either version 3 of the License, or (at your
10 (at your option) any later version. 10 option) any later version.
11 11
12 This program is distributed in the hope that it will be useful, 12 This program is distributed in the hope that it will be useful, but
13 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
15 GNU General Public License for more details. 15 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 along
18 along with gvpe; if not, write to the Free Software 18 with this program; if not, see <http://www.gnu.org/licenses/>.
19 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19
20 Additional permission under GNU GPL version 3 section 7
21
22 If you modify this Program, or any covered work, by linking or
23 combining it with the OpenSSL project's OpenSSL library (or a modified
24 version of that library), containing parts covered by the terms of the
25 OpenSSL or SSLeay licenses, the licensors of this Program grant you
26 additional permission to convey the resulting work. Corresponding
27 Source for a non-source form of such a combination shall include the
28 source code for the parts of OpenSSL used as well as that of the
29 covered work.
20*/ 30*/
21 31
22#include "config.h" 32#include "config.h"
23 33
24#include <cassert>
25
26#include <list> 34#include <list>
35#include <queue>
36#include <utility>
27 37
28#include <openssl/rand.h> 38#include <openssl/rand.h>
29#include <openssl/evp.h> 39#include <openssl/evp.h>
30#include <openssl/rsa.h> 40#include <openssl/rsa.h>
31#include <openssl/err.h> 41#include <openssl/err.h>
32
33#include "gettext.h"
34 42
35#include "conf.h" 43#include "conf.h"
36#include "slog.h" 44#include "slog.h"
37#include "device.h" 45#include "device.h"
38#include "vpn.h" 46#include "vpn.h"
… …
49#define ULTRA_FAST 1 57#define ULTRA_FAST 1
50#define HLOG 15 58#define HLOG 15
51#include "lzf/lzf.h" 59#include "lzf/lzf.h"
52#include "lzf/lzf_c.c" 60#include "lzf/lzf_c.c"
53#include "lzf/lzf_d.c" 61#include "lzf/lzf_d.c"
62
63//////////////////////////////////////////////////////////////////////////////
64
65static std::queue< std::pair<run_script_cb *, const char *> > rs_queue;
66static ev::child rs_child_ev;
67
68void // c++ requires external linkage here, apparently :(
69rs_child_cb (ev::child &w, int revents)
70{
71 w.stop ();
72
73 if (rs_queue.empty ())
74 return;
75
76 pid_t pid = run_script (*rs_queue.front ().first, false);
77 if (pid)
78 {
79 w.set (pid);
80 w.start ();
81 }
82 else
83 slog (L_WARN, rs_queue.front ().second);
84
85 delete rs_queue.front ().first;
86 rs_queue.pop ();
87}
88
89// despite the fancy name, this is quite a hack
90static void
91run_script_queued (run_script_cb *cb, const char *warnmsg)
92{
93 rs_queue.push (std::make_pair (cb, warnmsg));
94
95 if (!rs_child_ev.is_active ())
96 {
97 rs_child_ev.set<rs_child_cb> ();
98 rs_child_ev ();
99 }
100}
101
102//////////////////////////////////////////////////////////////////////////////
54 103
55struct crypto_ctx 104struct crypto_ctx
56{ 105{
57 EVP_CIPHER_CTX cctx; 106 EVP_CIPHER_CTX cctx;
58 HMAC_CTX hctx; 107 HMAC_CTX hctx;
… …
86 require (EVP_DigestUpdate(&ctx, &id, sizeof id)); 135 require (EVP_DigestUpdate(&ctx, &id, sizeof id));
87 require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0)); 136 require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0));
88 EVP_MD_CTX_cleanup (&ctx); 137 EVP_MD_CTX_cleanup (&ctx);
89} 138}
90 139
91struct rsa_entry { 140struct rsa_entry
141{
92 tstamp expire; 142 tstamp expire;
93 rsaid id; 143 rsaid id;
94 rsachallenge chg; 144 rsachallenge chg;
95}; 145};
96 146
97struct rsa_cache : list<rsa_entry> 147struct rsa_cache : list<rsa_entry>
98{ 148{
99 void cleaner_cb (time_watcher &w); time_watcher cleaner; 149 inline void cleaner_cb (ev::timer &w, int revents); ev::timer cleaner;
100 150
101 bool find (const rsaid &id, rsachallenge &chg) 151 bool find (const rsaid &id, rsachallenge &chg)
102 { 152 {
103 for (iterator i = begin (); i != end (); ++i) 153 for (iterator i = begin (); i != end (); ++i)
104 { 154 {
105 if (!memcmp (&id, &i->id, sizeof id) && i->expire > NOW) 155 if (!memcmp (&id, &i->id, sizeof id) && i->expire > ev_now ())
106 { 156 {
107 memcpy (&chg, &i->chg, sizeof chg); 157 memcpy (&chg, &i->chg, sizeof chg);
108 158
109 erase (i); 159 erase (i);
110 return true; 160 return true;
111 } 161 }
112 } 162 }
113 163
114 if (cleaner.at < NOW) 164 if (!cleaner.is_active ())
115 cleaner.start (NOW + RSA_TTL); 165 cleaner.again ();
116 166
117 return false; 167 return false;
118 } 168 }
119 169
120 void gen (rsaid &id, rsachallenge &chg) 170 void gen (rsaid &id, rsachallenge &chg)
121 { 171 {
122 rsa_entry e; 172 rsa_entry e;
123 173
124 RAND_bytes ((unsigned char *)&id, sizeof id); 174 RAND_bytes ((unsigned char *)&id, sizeof id);
125 RAND_bytes ((unsigned char *)&chg, sizeof chg); 175 RAND_bytes ((unsigned char *)&chg, sizeof chg);
126 176
127 e.expire = NOW + RSA_TTL; 177 e.expire = ev_now () + RSA_TTL;
128 e.id = id; 178 e.id = id;
129 memcpy (&e.chg, &chg, sizeof chg); 179 memcpy (&e.chg, &chg, sizeof chg);
130 180
131 push_back (e); 181 push_back (e);
132 182
133 if (cleaner.at < NOW) 183 if (!cleaner.is_active ())
134 cleaner.start (NOW + RSA_TTL); 184 cleaner.again ();
135 } 185 }
136 186
137 rsa_cache () 187 rsa_cache ()
138 : cleaner (this, &rsa_cache::cleaner_cb) 188 {
139 { } 189 cleaner.set<rsa_cache, &rsa_cache::cleaner_cb> (this);
190 cleaner.set (RSA_TTL, RSA_TTL);
191 }
140 192
141} rsa_cache; 193} rsa_cache;
142 194
143void rsa_cache::cleaner_cb (time_watcher &w) 195void rsa_cache::cleaner_cb (ev::timer &w, int revents)
144{ 196{
145 if (!empty ()) 197 if (empty ())
198 w.stop ();
199 else
146 { 200 {
147 w.start (NOW + RSA_TTL);
148
149 for (iterator i = begin (); i != end (); ) 201 for (iterator i = begin (); i != end (); )
150 if (i->expire <= NOW) 202 if (i->expire <= ev_now ())
151 i = erase (i); 203 i = erase (i);
152 else 204 else
153 ++i; 205 ++i;
154 } 206 }
155} 207}
156 208
157////////////////////////////////////////////////////////////////////////////// 209//////////////////////////////////////////////////////////////////////////////
158 210
159void pkt_queue::put (net_packet *p) 211pkt_queue::pkt_queue (double max_ttl, int max_queue)
212: max_ttl (max_ttl), max_queue (max_queue)
160{ 213{
161 if (queue[i]) 214 queue = new pkt [max_queue];
162 {
163 delete queue[i];
164 j = (j + 1) % QUEUEDEPTH;
165 }
166 215
167 queue[i] = p;
168
169 i = (i + 1) % QUEUEDEPTH;
170}
171
172net_packet *pkt_queue::get ()
173{
174 net_packet *p = queue[j];
175
176 if (p)
177 {
178 queue[j] = 0;
179 j = (j + 1) % QUEUEDEPTH;
180 }
181
182 return p;
183}
184
185pkt_queue::pkt_queue ()
186{
187 memset (queue, 0, sizeof (queue));
188 i = 0; 216 i = 0;
189 j = 0; 217 j = 0;
218
219 expire.set<pkt_queue, &pkt_queue::expire_cb> (this);
190} 220}
191 221
192pkt_queue::~pkt_queue () 222pkt_queue::~pkt_queue ()
193{ 223{
194 for (i = QUEUEDEPTH; --i > 0; ) 224 while (net_packet *p = get ())
225 delete p;
226
195 delete queue[i]; 227 delete [] queue;
196} 228}
197 229
230void pkt_queue::expire_cb (ev::timer &w, int revents)
231{
232 ev_tstamp expire = ev_now () - max_ttl;
233
234 for (;;)
235 {
236 if (empty ())
237 break;
238
239 double diff = queue[j].tstamp - expire;
240
241 if (diff >= 0.)
242 {
243 w.start (diff > 0.5 ? diff : 0.5);
244 break;
245 }
246
247 delete get ();
248 }
249}
250
251void pkt_queue::put (net_packet *p)
252{
253 ev_tstamp now = ev_now ();
254
255 // start expiry timer
256 if (empty ())
257 expire.start (max_ttl);
258
259 int ni = i + 1 == max_queue ? 0 : i + 1;
260
261 if (ni == j)
262 delete get ();
263
264 queue[i].pkt = p;
265 queue[i].tstamp = now;
266
267 i = ni;
268}
269
270net_packet *pkt_queue::get ()
271{
272 if (empty ())
273 return 0;
274
275 net_packet *p = queue[j].pkt;
276 queue[j].pkt = 0;
277
278 j = j + 1 == max_queue ? 0 : j + 1;
279
280 return p;
281}
282
198struct net_rateinfo { 283struct net_rateinfo
284{
199 u32 host; 285 u32 host;
200 double pcnt, diff; 286 double pcnt, diff;
201 tstamp last; 287 tstamp last;
202}; 288};
203 289
… …
222 iterator i; 308 iterator i;
223 309
224 for (i = begin (); i != end (); ) 310 for (i = begin (); i != end (); )
225 if (i->host == host) 311 if (i->host == host)
226 break; 312 break;
227 else if (i->last < NOW - NRL_EXPIRE) 313 else if (i->last < ev_now () - NRL_EXPIRE)
228 i = erase (i); 314 i = erase (i);
229 else 315 else
230 i++; 316 i++;
231 317
232 if (i == end ()) 318 if (i == end ())
… …
234 net_rateinfo ri; 320 net_rateinfo ri;
235 321
236 ri.host = host; 322 ri.host = host;
237 ri.pcnt = 1.; 323 ri.pcnt = 1.;
238 ri.diff = NRL_MAXDIF; 324 ri.diff = NRL_MAXDIF;
239 ri.last = NOW; 325 ri.last = ev_now ();
240 326
241 push_front (ri); 327 push_front (ri);
242 328
243 return true; 329 return true;
244 } 330 }
… …
246 { 332 {
247 net_rateinfo ri (*i); 333 net_rateinfo ri (*i);
248 erase (i); 334 erase (i);
249 335
250 ri.pcnt = ri.pcnt * NRL_ALPHA; 336 ri.pcnt = ri.pcnt * NRL_ALPHA;
251 ri.diff = ri.diff * NRL_ALPHA + (NOW - ri.last); 337 ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last);
252 338
253 ri.last = NOW; 339 ri.last = ev_now ();
254 340
255 double dif = ri.diff / ri.pcnt; 341 double dif = ri.diff / ri.pcnt;
256 342
257 bool send = dif > NRL_CUTOFF; 343 bool send = dif > NRL_CUTOFF;
258 344
… …
468 f |= FEATURE_COMPRESSION; 554 f |= FEATURE_COMPRESSION;
469#endif 555#endif
470#if ENABLE_ROHC 556#if ENABLE_ROHC
471 f |= FEATURE_ROHC; 557 f |= FEATURE_ROHC;
472#endif 558#endif
559#if ENABLE_BRIDGING
560 f |= FEATURE_BRIDGING;
561#endif
473 return f; 562 return f;
474 } 563 }
475}; 564};
476 565
477void config_packet::setup (ptype type, int dst) 566void config_packet::setup (ptype type, int dst)
478{ 567{
479 prot_major = PROTOCOL_MAJOR; 568 prot_major = PROTOCOL_MAJOR;
480 prot_minor = PROTOCOL_MINOR; 569 prot_minor = PROTOCOL_MINOR;
481 randsize = RAND_SIZE; 570 randsize = RAND_SIZE;
482 hmaclen = HMACLENGTH; 571 hmaclen = HMACLENGTH;
483 flags = ENABLE_COMPRESSION ? 0x81 : 0x80; 572 flags = 0;
484 challengelen = sizeof (rsachallenge); 573 challengelen = sizeof (rsachallenge);
485 features = get_features (); 574 features = get_features ();
486 575
487 cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); 576 cipher_nid = htonl (EVP_CIPHER_nid (CIPHER));
488 digest_nid = htonl (EVP_MD_type (RSA_HASH)); 577 digest_nid = htonl (EVP_MD_type (RSA_HASH));
… …
498 slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); 587 slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR);
499 else if (randsize != RAND_SIZE) 588 else if (randsize != RAND_SIZE)
500 slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE); 589 slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE);
501 else if (hmaclen != HMACLENGTH) 590 else if (hmaclen != HMACLENGTH)
502 slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH); 591 slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH);
503#if 0 // this implementation should handle all flag settings
504 else if (flags != curflags ())
505 slog (L_WARN, _("flag mismatch (remote %x <=> local %x)"), flags, curflags ());
506#endif
507 else if (challengelen != sizeof (rsachallenge)) 592 else if (challengelen != sizeof (rsachallenge))
508 slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge)); 593 slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge));
509 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER))) 594 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER)))
510 slog (L_WARN, _("cipher mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER)); 595 slog (L_WARN, _("cipher mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER));
511 else if (digest_nid != htonl (EVP_MD_type (RSA_HASH))) 596 else if (digest_nid != htonl (EVP_MD_type (RSA_HASH)))
… …
587///////////////////////////////////////////////////////////////////////////// 672/////////////////////////////////////////////////////////////////////////////
588 673
589void 674void
590connection::connection_established () 675connection::connection_established ()
591{ 676{
677 slog (L_TRACE, _("%s: possible connection establish (ictx %d, octx %d)"), conf->nodename, !!ictx, !!octx);
678
592 if (ictx && octx) 679 if (ictx && octx)
593 { 680 {
594 connectmode = conf->connectmode;
595
596 // make sure rekeying timeouts are slightly asymmetric 681 // make sure rekeying timeouts are slightly asymmetric
597 rekey.start (NOW + ::conf.rekey 682 ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0);
598 + (conf->id > THISNODE->id ? 10 : 0)); 683 rekey.start (rekey_interval, rekey_interval);
599 keepalive.start (NOW + ::conf.keepalive); 684 keepalive.start (::conf.keepalive);
600 685
601 // send queued packets 686 // send queued packets
602 if (ictx && octx) 687 if (ictx && octx)
603 { 688 {
604 while (tap_packet *p = (tap_packet *)data_queue.get ()) 689 while (tap_packet *p = (tap_packet *)data_queue.get ())
605 { 690 {
606 send_data_packet (p); 691 if (p->len) send_data_packet (p);
607 delete p; 692 delete p;
608 } 693 }
609 694
610 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) 695 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ())
611 { 696 {
612 send_vpn_packet (p, si, IPTOS_RELIABILITY); 697 if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY);
613 delete p; 698 delete p;
614 } 699 }
615 } 700 }
701
702 vpn->connection_established (this);
616 } 703 }
617 else 704 else
618 { 705 {
619 retry_cnt = 0; 706 retry_cnt = 0;
620 establish_connection.start (NOW + 5); 707 establish_connection.start (5);
621 keepalive.stop (); 708 keepalive.stop ();
622 rekey.stop (); 709 rekey.stop ();
623 } 710 }
624} 711}
625 712
626void 713void
627connection::reset_si () 714connection::reset_si ()
628{ 715{
716 if (vpn->can_direct (THISNODE, conf))
629 protocol = best_protocol (THISNODE->protocols & conf->protocols); 717 protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ());
630 718 else
631 // mask out protocols we cannot establish 719 {
632 if (!conf->udp_port) protocol &= ~PROT_UDPv4; 720 slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename);
633 if (!conf->tcp_port) protocol &= ~PROT_TCPv4; 721 protocol = 0;
634 if (!conf->dns_port) protocol &= ~PROT_DNSv4; 722 }
635 723
636 si.set (conf, protocol); 724 si.set (conf, protocol);
725
726 is_direct = si.valid ();
637} 727}
638 728
639// ensure sockinfo is valid, forward if necessary 729// ensure sockinfo is valid, forward if necessary
640const sockinfo & 730const sockinfo &
641connection::forward_si (const sockinfo &si) const 731connection::forward_si (const sockinfo &si) const
642{ 732{
643 if (!si.valid ()) 733 if (!si.valid ())
644 { 734 {
645 connection *r = vpn->find_router (); 735 connection *r = vpn->find_router_for (this);
646 736
647 if (r) 737 if (r)
648 { 738 {
649 slog (L_DEBUG, _("%s: no common protocol, trying indirectly through %s (%s)"), 739 slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."),
650 conf->nodename, r->conf->nodename, (const char *)r->si); 740 conf->nodename, r->conf->nodename);
651 return r->si; 741 return r->si;
652 } 742 }
653 else 743 else
654 slog (L_DEBUG, _("%s: node unreachable, no common protocol"), 744 slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."),
655 conf->nodename); 745 conf->nodename);
656 } 746 }
657 747
658 return si; 748 return si;
659} 749}
… …
669connection::send_ping (const sockinfo &si, u8 pong) 759connection::send_ping (const sockinfo &si, u8 pong)
670{ 760{
671 ping_packet *pkt = new ping_packet; 761 ping_packet *pkt = new ping_packet;
672 762
673 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); 763 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING);
764
765 slog (L_TRACE, ">>%d %s [%s]", conf->id, pong ? "PT_PONG" : "PT_PING", (const char *)si);
766
674 send_vpn_packet (pkt, si, IPTOS_LOWDELAY); 767 send_vpn_packet (pkt, si, IPTOS_LOWDELAY);
675 768
676 delete pkt; 769 delete pkt;
677} 770}
678 771
… …
725} 818}
726 819
727void 820void
728connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) 821connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols)
729{ 822{
730 slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", 823 slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)",
731 conf->id, rid, (const char *)rsi); 824 conf->id, rid, (const char *)rsi);
732 825
733 connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); 826 connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols);
734 827
735 r->hmac_set (octx); 828 r->hmac_set (octx);
736 send_vpn_packet (r, si); 829 send_vpn_packet (r, si);
737 830
738 delete r; 831 delete r;
739} 832}
740 833
741void 834inline void
742connection::establish_connection_cb (time_watcher &w) 835connection::establish_connection_cb (ev::timer &w, int revents)
743{ 836{
744 if (!ictx 837 if (!ictx
745 && conf != THISNODE 838 && conf != THISNODE
746 && connectmode != conf_node::C_NEVER 839 && connectmode != conf_node::C_NEVER
747 && connectmode != conf_node::C_DISABLED 840 && connectmode != conf_node::C_DISABLED
748 && NOW > w.at) 841 && !w.is_active ())
749 { 842 {
750 double retry_int = double (retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2)) * 0.6; 843 // a bit hacky, if ondemand, and packets are no longer queued, then reset the connection
751 844 // and stop trying. should probably be handled by a per-connection expire handler.
752 if (retry_int < conf->max_retry) 845 if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ())
846 {
847 reset_connection ();
753 retry_cnt++; 848 return;
754 else 849 }
755 retry_int = conf->max_retry;
756 850
757 w.start (NOW + retry_int); 851 last_establish_attempt = ev_now ();
852
853 ev::tstamp retry_int = ev::tstamp (retry_cnt & 3
854 ? (retry_cnt & 3) + 1
855 : 1 << (retry_cnt >> 2));
758 856
759 reset_si (); 857 reset_si ();
760 858
761 if (si.prot && !si.host) 859 bool slow = si.prot & PROT_SLOW;
860
861 if (si.prot && !si.host && vpn->can_direct (THISNODE, conf))
862 {
863 /*TODO*/ /* start the timer so we don't recurse endlessly */
864 w.start (1);
762 vpn->send_connect_request (conf->id); 865 vpn->send_connect_request (this);
866 }
763 else 867 else
764 { 868 {
869 if (si.valid ())
870 slog (L_DEBUG, _("%s: sending direct connection request to %s."),
871 conf->nodename, (const char *)si);
872
765 const sockinfo &dsi = forward_si (si); 873 const sockinfo &dsi = forward_si (si);
874
875 slow = slow || (dsi.prot & PROT_SLOW);
766 876
767 if (dsi.valid () && auth_rate_limiter.can (dsi)) 877 if (dsi.valid () && auth_rate_limiter.can (dsi))
768 { 878 {
769 if (retry_cnt < 4) 879 if (retry_cnt < 4)
770 send_auth_request (dsi, true); 880 send_auth_request (dsi, true);
771 else 881 else
772 send_ping (dsi, 0); 882 send_ping (dsi, 0);
773 } 883 }
774 } 884 }
885
886 retry_int *= slow ? 8. : 0.9;
887
888 if (retry_int < conf->max_retry)
889 retry_cnt++;
890 else
891 retry_int = conf->max_retry;
892
893 w.start (retry_int);
775 } 894 }
776} 895}
777 896
778void 897void
779connection::reset_connection () 898connection::reset_connection ()
… …
782 { 901 {
783 slog (L_INFO, _("%s(%s): connection lost"), 902 slog (L_INFO, _("%s(%s): connection lost"),
784 conf->nodename, (const char *)si); 903 conf->nodename, (const char *)si);
785 904
786 if (::conf.script_node_down) 905 if (::conf.script_node_down)
787 run_script (run_script_cb (this, &connection::script_node_down), false); 906 {
907 run_script_cb *cb = new run_script_cb;
908 cb->set<connection, &connection::script_node_down> (this);
909 run_script_queued (cb, _("node-down command execution failed, continuing."));
910 }
788 } 911 }
789 912
790 delete ictx; ictx = 0; 913 delete ictx; ictx = 0;
791 delete octx; octx = 0; 914 delete octx; octx = 0;
792#if ENABLE_DNS 915#if ENABLE_DNS
793 dnsv4_reset_connection (); 916 dnsv4_reset_connection ();
794#endif 917#endif
795 918
796 si.host = 0; 919 si.host = 0;
797 920
798 last_activity = 0; 921 last_activity = 0.;
922 //last_si_change = 0.;
799 retry_cnt = 0; 923 retry_cnt = 0;
800 924
801 rekey.stop (); 925 rekey.stop ();
802 keepalive.stop (); 926 keepalive.stop ();
803 establish_connection.stop (); 927 establish_connection.stop ();
… …
810 send_reset (si); 934 send_reset (si);
811 935
812 reset_connection (); 936 reset_connection ();
813} 937}
814 938
815void 939// poor-man's rekeying
816connection::rekey_cb (time_watcher &w) 940inline void
941connection::rekey_cb (ev::timer &w, int revents)
817{ 942{
818 reset_connection (); 943 reset_connection ();
819 establish_connection (); 944 establish_connection ();
820} 945}
821 946
… …
837 if (oseqno > MAX_SEQNO) 962 if (oseqno > MAX_SEQNO)
838 rekey (); 963 rekey ();
839} 964}
840 965
841void 966void
967connection::post_inject_queue ()
968{
969 // force a connection every now and when when packets are sent (max 1/s)
970 if (ev_now () - last_establish_attempt >= 0.95) // arbitrary
971 establish_connection.stop ();
972
973 establish_connection ();
974}
975
976void
842connection::inject_data_packet (tap_packet *pkt, bool broadcast/*TODO DDD*/) 977connection::inject_data_packet (tap_packet *pkt)
843{ 978{
844 if (ictx && octx) 979 if (ictx && octx)
845 send_data_packet (pkt); 980 send_data_packet (pkt);
846 else 981 else
847 { 982 {
848 if (!broadcast)//DDDD
849 data_queue.put (new tap_packet (*pkt)); 983 data_queue.put (new tap_packet (*pkt));
850 984 post_inject_queue ();
851 establish_connection ();
852 } 985 }
853} 986}
854 987
855void connection::inject_vpn_packet (vpn_packet *pkt, int tos) 988void connection::inject_vpn_packet (vpn_packet *pkt, int tos)
856{ 989{
857 if (ictx && octx) 990 if (ictx && octx)
858 send_vpn_packet (pkt, si, tos); 991 send_vpn_packet (pkt, si, tos);
859 else 992 else
860 { 993 {
861 vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); 994 vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt));
862 995 post_inject_queue ();
863 establish_connection ();
864 } 996 }
865} 997}
866 998
867void 999void
868connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) 1000connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi)
869{ 1001{
870 last_activity = NOW; 1002 last_activity = ev_now ();
871 1003
872 slog (L_NOISE, "<<%d received packet type %d from %d to %d", 1004 slog (L_NOISE, "<<%d received packet type %d from %d to %d.",
873 conf->id, pkt->typ (), pkt->src (), pkt->dst ()); 1005 conf->id, pkt->typ (), pkt->src (), pkt->dst ());
1006
1007 if (connectmode == conf_node::C_DISABLED)
1008 return;
874 1009
875 switch (pkt->typ ()) 1010 switch (pkt->typ ())
876 { 1011 {
877 case vpn_packet::PT_PING: 1012 case vpn_packet::PT_PING:
878 // we send pings instead of auth packets after some retries, 1013 // we send pings instead of auth packets after some retries,
… …
882 { 1017 {
883 if (auth_rate_limiter.can (rsi)) 1018 if (auth_rate_limiter.can (rsi))
884 send_auth_request (rsi, true); 1019 send_auth_request (rsi, true);
885 } 1020 }
886 else 1021 else
1022 // we would love to change thre socket address here, but ping's aren't
1023 // authenticated, so we best ignore it.
887 send_ping (rsi, 1); // pong 1024 send_ping (rsi, 1); // pong
888 1025
889 break; 1026 break;
890 1027
891 case vpn_packet::PT_PONG: 1028 case vpn_packet::PT_PONG:
… …
897 1034
898 config_packet *p = (config_packet *) pkt; 1035 config_packet *p = (config_packet *) pkt;
899 1036
900 if (!p->chk_config ()) 1037 if (!p->chk_config ())
901 { 1038 {
902 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"), 1039 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node."),
903 conf->nodename, (const char *)rsi); 1040 conf->nodename, (const char *)rsi);
904 connectmode = conf_node::C_DISABLED; 1041 connectmode = conf_node::C_DISABLED;
905 } 1042 }
906 else if (connectmode == conf_node::C_ALWAYS) 1043 else if (connectmode == conf_node::C_ALWAYS)
907 establish_connection (); 1044 establish_connection ();
… …
938 delete octx; 1075 delete octx;
939 1076
940 octx = new crypto_ctx (k, 1); 1077 octx = new crypto_ctx (k, 1);
941 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; 1078 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff;
942 1079
943 // compatibility code, remove when no longer required
944 if (p->flags & 1) p->features |= FEATURE_COMPRESSION;
945
946 conf->protocols = p->protocols; 1080 conf->protocols = p->protocols;
947 features = p->features & config_packet::get_features (); 1081 features = p->features & config_packet::get_features ();
948 1082
949 send_auth_response (rsi, p->id, k); 1083 send_auth_response (rsi, p->id, k);
950 1084
… …
952 1086
953 break; 1087 break;
954 } 1088 }
955 } 1089 }
956 else 1090 else
957 slog (L_WARN, _("%s(%s): protocol mismatch"), 1091 slog (L_WARN, _("%s(%s): protocol mismatch."),
958 conf->nodename, (const char *)rsi); 1092 conf->nodename, (const char *)rsi);
959 1093
960 send_reset (rsi); 1094 send_reset (rsi);
961 } 1095 }
962 1096
… …
977 1111
978 rsachallenge chg; 1112 rsachallenge chg;
979 1113
980 if (!rsa_cache.find (p->id, chg)) 1114 if (!rsa_cache.find (p->id, chg))
981 { 1115 {
982 slog (L_ERR, _("%s(%s): unrequested auth response ignored"), 1116 slog (L_ERR, _("%s(%s): unrequested auth response, ignoring."),
983 conf->nodename, (const char *)rsi); 1117 conf->nodename, (const char *)rsi);
984 break; 1118 break;
985 } 1119 }
986 else 1120 else
987 { 1121 {
988 crypto_ctx *cctx = new crypto_ctx (chg, 0); 1122 crypto_ctx *cctx = new crypto_ctx (chg, 0);
989 1123
990 if (!p->hmac_chk (cctx)) 1124 if (!p->hmac_chk (cctx))
991 { 1125 {
992 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" 1126 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n"
993 "could be an attack, or just corruption or a synchronization error"), 1127 "could be an attack, or just corruption or a synchronization error."),
994 conf->nodename, (const char *)rsi); 1128 conf->nodename, (const char *)rsi);
995 break; 1129 break;
996 } 1130 }
997 else 1131 else
998 { 1132 {
… …
1009 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid 1143 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
1010 1144
1011 si = rsi; 1145 si = rsi;
1012 protocol = rsi.prot; 1146 protocol = rsi.prot;
1013 1147
1148 slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."),
1149 conf->nodename, (const char *)rsi,
1150 is_direct ? "direct" : "routed",
1151 p->prot_major, p->prot_minor);
1152
1014 connection_established (); 1153 connection_established ();
1015 1154
1016 slog (L_INFO, _("%s(%s): connection established, protocol version %d.%d"),
1017 conf->nodename, (const char *)rsi,
1018 p->prot_major, p->prot_minor);
1019
1020 if (::conf.script_node_up) 1155 if (::conf.script_node_up)
1021 run_script (run_script_cb (this, &connection::script_node_up), false); 1156 {
1157 run_script_cb *cb = new run_script_cb;
1158 cb->set<connection, &connection::script_node_up> (this);
1159 run_script_queued (cb, _("node-up command execution failed, continuing."));
1160 }
1022 1161
1023 break; 1162 break;
1024 } 1163 }
1025 else 1164 else
1026 slog (L_ERR, _("%s(%s): sent and received challenge do not match"), 1165 slog (L_ERR, _("%s(%s): sent and received challenge do not match."),
1027 conf->nodename, (const char *)rsi); 1166 conf->nodename, (const char *)rsi);
1028 } 1167 }
1029 1168
1030 delete cctx; 1169 delete cctx;
1031 } 1170 }
… …
1047 { 1186 {
1048 vpndata_packet *p = (vpndata_packet *)pkt; 1187 vpndata_packet *p = (vpndata_packet *)pkt;
1049 1188
1050 if (!p->hmac_chk (ictx)) 1189 if (!p->hmac_chk (ictx))
1051 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" 1190 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n"
1052 "could be an attack, or just corruption or a synchronization error"), 1191 "could be an attack, or just corruption or a synchronization error."),
1053 conf->nodename, (const char *)rsi); 1192 conf->nodename, (const char *)rsi);
1054 else 1193 else
1055 { 1194 {
1056 u32 seqno; 1195 u32 seqno;
1057 tap_packet *d = p->unpack (this, seqno); 1196 tap_packet *d = p->unpack (this, seqno);
1197 int seqclass = iseqno.seqno_classify (seqno);
1058 1198
1059 if (iseqno.recv_ok (seqno)) 1199 if (seqclass == 0) // ok
1060 { 1200 {
1061 vpn->tap->send (d); 1201 vpn->tap->send (d);
1062 1202
1063 if (si != rsi) 1203 if (si != rsi)
1064 { 1204 {
1065 // fast re-sync on connection changes, useful especially for tcp/ip 1205 // fast re-sync on source address changes, useful especially for tcp/ip
1206 //if (last_si_change < ev_now () + 5.)
1066 si = rsi; 1207 // {
1067
1068 slog (L_INFO, _("%s(%s): socket address changed to %s"), 1208 slog (L_INFO, _("%s(%s): changing socket address to %s."),
1069 conf->nodename, (const char *)si, (const char *)rsi); 1209 conf->nodename, (const char *)si, (const char *)rsi);
1210
1211 si = rsi;
1212 // }
1213 //else
1214 // slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."),
1215 // conf->nodename, (const char *)si, (const char *)rsi);
1070 } 1216 }
1217 }
1218 else if (seqclass == 1) // far history
1219 slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). "
1220 "possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1);
1221 else if (seqclass == 2) // in-window duplicate, happens often on wireless
1222 slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). "
1223 "possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1);
1224 else if (seqclass == 3) // reset
1225 {
1226 slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). "
1227 "probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1);
1228 send_reset (rsi);
1071 } 1229 }
1072 1230
1073 delete d; 1231 delete d;
1074 break; 1232 break;
1075 } 1233 }
… …
1081 case vpn_packet::PT_CONNECT_REQ: 1239 case vpn_packet::PT_CONNECT_REQ:
1082 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) 1240 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx))
1083 { 1241 {
1084 connect_req_packet *p = (connect_req_packet *) pkt; 1242 connect_req_packet *p = (connect_req_packet *) pkt;
1085 1243
1086 assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything 1244 if (p->id > 0 && p->id <= vpn->conns.size ())
1087 connection *c = vpn->conns[p->id - 1];
1088 conf->protocols = p->protocols;
1089
1090 slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n",
1091 conf->id, p->id, c->ictx && c->octx);
1092
1093 if (c->ictx && c->octx)
1094 { 1245 {
1246 connection *c = vpn->conns[p->id - 1];
1247 conf->protocols = p->protocols;
1248
1249 slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]",
1250 conf->id, p->id, c->ictx && c->octx);
1251
1252 if (c->ictx && c->octx)
1253 {
1095 // send connect_info packets to both sides, in case one is 1254 // send connect_info packets to both sides, in case one is
1096 // behind a nat firewall (or both ;) 1255 // behind a nat firewall (or both ;)
1097 c->send_connect_info (conf->id, si, conf->protocols); 1256 c->send_connect_info (conf->id, si, conf->protocols);
1098 send_connect_info (c->conf->id, c->si, c->conf->protocols); 1257 send_connect_info (c->conf->id, c->si, c->conf->protocols);
1258 }
1259 else
1260 c->establish_connection ();
1099 } 1261 }
1100 else 1262 else
1101 c->establish_connection (); 1263 slog (L_WARN,
1264 _("received authenticated connection request from unknown node #%d, config file mismatch?"),
1265 p->id);
1102 } 1266 }
1103 1267
1104 break; 1268 break;
1105 1269
1106 case vpn_packet::PT_CONNECT_INFO: 1270 case vpn_packet::PT_CONNECT_INFO:
1107 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) 1271 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx))
1108 { 1272 {
1109 connect_info_packet *p = (connect_info_packet *)pkt; 1273 connect_info_packet *p = (connect_info_packet *)pkt;
1110 1274
1111 if (p->id > 0 && p->id <= vpn->conns.size ()) // hmac-auth does not mean we accept anything 1275 if (p->id > 0 && p->id <= vpn->conns.size ())
1112 { 1276 {
1113 connection *c = vpn->conns[p->id - 1]; 1277 connection *c = vpn->conns[p->id - 1];
1114 1278
1115 c->conf->protocols = p->protocols; 1279 c->conf->protocols = p->protocols;
1116 protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); 1280 protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf));
… …
1122 const sockinfo &dsi = forward_si (p->si); 1286 const sockinfo &dsi = forward_si (p->si);
1123 1287
1124 if (dsi.valid ()) 1288 if (dsi.valid ())
1125 c->send_auth_request (dsi, true); 1289 c->send_auth_request (dsi, true);
1126 } 1290 }
1291 else
1292 slog (L_WARN,
1293 _("received authenticated connection request from unknown node #%d, config file mismatch?"),
1294 p->id);
1127 } 1295 }
1128 1296
1129 break; 1297 break;
1130 1298
1131 default: 1299 default:
1132 send_reset (rsi); 1300 send_reset (rsi);
1133 break; 1301 break;
1134 } 1302 }
1135} 1303}
1136 1304
1137void connection::keepalive_cb (time_watcher &w) 1305inline void
1306connection::keepalive_cb (ev::timer &w, int revents)
1138{ 1307{
1139 if (NOW >= last_activity + ::conf.keepalive + 30) 1308 if (ev_now () >= last_activity + ::conf.keepalive + 30)
1140 { 1309 {
1141 reset_connection (); 1310 reset_connection ();
1142 establish_connection (); 1311 establish_connection ();
1143 } 1312 }
1144 else if (NOW < last_activity + ::conf.keepalive) 1313 else if (ev_now () < last_activity + ::conf.keepalive)
1145 w.start (last_activity + ::conf.keepalive); 1314 w.start (last_activity + ::conf.keepalive - ev::now ());
1146 else if (conf->connectmode != conf_node::C_ONDEMAND 1315 else if (conf->connectmode != conf_node::C_ONDEMAND
1147 || THISNODE->connectmode != conf_node::C_ONDEMAND) 1316 || THISNODE->connectmode != conf_node::C_ONDEMAND)
1148 { 1317 {
1149 send_ping (si); 1318 send_ping (si);
1150 w.start (NOW + 5); 1319 w.start (5);
1151 } 1320 }
1152 else if (NOW < last_activity + ::conf.keepalive + 10) 1321 else if (ev_now () < last_activity + ::conf.keepalive + 10)
1153 // hold ondemand connections implicitly a few seconds longer 1322 // hold ondemand connections implicitly a few seconds longer
1154 // should delete octx, though, or something like that ;) 1323 // should delete octx, though, or something like that ;)
1155 w.start (last_activity + ::conf.keepalive + 10); 1324 w.start (last_activity + ::conf.keepalive + 10 - ev::now ());
1156 else 1325 else
1157 reset_connection (); 1326 reset_connection ();
1158} 1327}
1159 1328
1160void connection::send_connect_request (int id) 1329void connection::send_connect_request (int id)
… …
1166 send_vpn_packet (p, si); 1335 send_vpn_packet (p, si);
1167 1336
1168 delete p; 1337 delete p;
1169} 1338}
1170 1339
1340void connection::script_init_env (const char *ext)
1341{
1342 char *env;
1343 asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env);
1344 asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env);
1345 asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext,
1346 0xfe, 0xfd, 0x80, 0x00, conf->id >> 8,
1347 conf->id & 0xff); putenv (env);
1348}
1349
1171void connection::script_node () 1350void connection::script_init_connect_env ()
1172{ 1351{
1173 vpn->script_if_up (); 1352 vpn->script_init_env ();
1174 1353
1175 char *env; 1354 char *env;
1176 asprintf (&env, "DESTID=%d", conf->id); putenv (env); 1355 asprintf (&env, "DESTID=%d", conf->id); putenv (env);
1177 asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); 1356 asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env);
1178 asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); 1357 asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env);
1179 asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); 1358 asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env);
1180} 1359}
1181 1360
1361inline const char *
1182const char *connection::script_node_up () 1362connection::script_node_up ()
1183{ 1363{
1184 script_node (); 1364 script_init_connect_env ();
1185 1365
1186 putenv ("STATE=up"); 1366 putenv ((char *)"STATE=up");
1187 1367
1368 char *filename;
1369 asprintf (&filename,
1370 "%s/%s",
1371 confbase,
1188 return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; 1372 ::conf.script_node_up ? ::conf.script_node_up : "node-up");
1189}
1190 1373
1374 return filename;
1375}
1376
1377inline const char *
1191const char *connection::script_node_down () 1378connection::script_node_down ()
1192{ 1379{
1193 script_node (); 1380 script_init_connect_env ();
1194 1381
1195 putenv ("STATE=down"); 1382 putenv ((char *)"STATE=down");
1196 1383
1197 return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; 1384 char *filename;
1385 asprintf (&filename,
1386 "%s/%s",
1387 confbase,
1388 ::conf.script_node_down ? ::conf.script_node_down : "node-down");
1389
1390 return filename;
1198} 1391}
1199 1392
1200connection::connection (struct vpn *vpn, conf_node *conf) 1393connection::connection (struct vpn *vpn, conf_node *conf)
1201: vpn(vpn), conf(conf) 1394: vpn(vpn), conf(conf),
1202, rekey (this, &connection::rekey_cb)
1203, keepalive (this, &connection::keepalive_cb)
1204, establish_connection (this, &connection::establish_connection_cb)
1205#if ENABLE_DNS 1395#if ENABLE_DNS
1206, dns (0) 1396 dns (0),
1207#endif 1397#endif
1398 data_queue(conf->max_ttl, conf->max_queue + 1),
1399 vpn_queue(conf->max_ttl, conf->max_queue + 1)
1208{ 1400{
1401 rekey .set<connection, &connection::rekey_cb > (this);
1402 keepalive .set<connection, &connection::keepalive_cb > (this);
1403 establish_connection.set<connection, &connection::establish_connection_cb> (this);
1404
1405 last_establish_attempt = 0.;
1209 octx = ictx = 0; 1406 octx = ictx = 0;
1210 retry_cnt = 0;
1211 1407
1212 if (!conf->protocols) // make sure some protocol is enabled 1408 if (!conf->protocols) // make sure some protocol is enabled
1213 conf->protocols = PROT_UDPv4; 1409 conf->protocols = PROT_UDPv4;
1214 1410
1215 connectmode = conf_node::C_ALWAYS; // initial setting 1411 connectmode = conf->connectmode;
1412
1413 // queue a dummy packet to force an initial connection attempt
1414 if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED)
1415 vpn_queue.put (new net_packet);
1416
1216 reset_connection (); 1417 reset_connection ();
1217} 1418}
1218 1419
1219connection::~connection () 1420connection::~connection ()
1220{ 1421{

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