1 | /* |
1 | /* |
2 | connection.C -- manage a single connection |
2 | connection.C -- manage a single connection |
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3 | Copyright (C) 2003 Marc Lehmann <pcg@goof.com> |
3 | |
4 | |
4 | This program is free software; you can redistribute it and/or modify |
5 | This program is free software; you can redistribute it and/or modify |
5 | it under the terms of the GNU General Public License as published by |
6 | it under the terms of the GNU General Public License as published by |
6 | the Free Software Foundation; either version 2 of the License, or |
7 | the Free Software Foundation; either version 2 of the License, or |
7 | (at your option) any later version. |
8 | (at your option) any later version. |
… | |
… | |
35 | #include "slog.h" |
36 | #include "slog.h" |
36 | #include "device.h" |
37 | #include "device.h" |
37 | #include "vpn.h" |
38 | #include "vpn.h" |
38 | #include "connection.h" |
39 | #include "connection.h" |
39 | |
40 | |
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41 | #include "netcompat.h" |
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42 | |
40 | #if !HAVE_RAND_PSEUDO_BYTES |
43 | #if !HAVE_RAND_PSEUDO_BYTES |
41 | # define RAND_pseudo_bytes RAND_bytes |
44 | # define RAND_pseudo_bytes RAND_bytes |
42 | #endif |
45 | #endif |
43 | |
46 | |
44 | #define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic |
47 | #define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic |
… | |
… | |
147 | } |
150 | } |
148 | } |
151 | } |
149 | |
152 | |
150 | ////////////////////////////////////////////////////////////////////////////// |
153 | ////////////////////////////////////////////////////////////////////////////// |
151 | |
154 | |
152 | void pkt_queue::put (tap_packet *p) |
155 | void pkt_queue::put (net_packet *p) |
153 | { |
156 | { |
154 | if (queue[i]) |
157 | if (queue[i]) |
155 | { |
158 | { |
156 | delete queue[i]; |
159 | delete queue[i]; |
157 | j = (j + 1) % QUEUEDEPTH; |
160 | j = (j + 1) % QUEUEDEPTH; |
… | |
… | |
160 | queue[i] = p; |
163 | queue[i] = p; |
161 | |
164 | |
162 | i = (i + 1) % QUEUEDEPTH; |
165 | i = (i + 1) % QUEUEDEPTH; |
163 | } |
166 | } |
164 | |
167 | |
165 | tap_packet *pkt_queue::get () |
168 | net_packet *pkt_queue::get () |
166 | { |
169 | { |
167 | tap_packet *p = queue[j]; |
170 | net_packet *p = queue[j]; |
168 | |
171 | |
169 | if (p) |
172 | if (p) |
170 | { |
173 | { |
171 | queue[j] = 0; |
174 | queue[j] = 0; |
172 | j = (j + 1) % QUEUEDEPTH; |
175 | j = (j + 1) % QUEUEDEPTH; |
… | |
… | |
197 | // only do action once every x seconds per host whole allowing bursts. |
200 | // only do action once every x seconds per host whole allowing bursts. |
198 | // this implementation ("splay list" ;) is inefficient, |
201 | // this implementation ("splay list" ;) is inefficient, |
199 | // but low on resources. |
202 | // but low on resources. |
200 | struct net_rate_limiter : list<net_rateinfo> |
203 | struct net_rate_limiter : list<net_rateinfo> |
201 | { |
204 | { |
202 | static const double ALPHA = 1. - 1. / 180.; // allow bursts |
205 | static const double ALPHA = 1. - 1. / 600.; // allow bursts |
203 | static const double CUTOFF = 10.; // one event every CUTOFF seconds |
206 | static const double CUTOFF = 10.; // one event every CUTOFF seconds |
204 | static const double EXPIRE = CUTOFF * 30.; // expire entries after this time |
207 | static const double EXPIRE = CUTOFF * 30.; // expire entries after this time |
205 | static const double MAXDIF = CUTOFF * (1. / (1. - ALPHA)); // maximum diff /count value |
208 | static const double MAXDIF = CUTOFF * (1. / (1. - ALPHA)); // maximum diff /count value |
206 | |
209 | |
207 | bool can (const sockinfo &si) { return can((u32)si.host); } |
210 | bool can (const sockinfo &si) { return can((u32)si.host); } |
208 | bool can (u32 host); |
211 | bool can (u32 host); |
209 | }; |
212 | }; |
210 | |
213 | |
211 | net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
214 | net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
212 | |
215 | |
… | |
… | |
475 | set_hdr (type, dst); |
478 | set_hdr (type, dst); |
476 | } |
479 | } |
477 | |
480 | |
478 | bool config_packet::chk_config () const |
481 | bool config_packet::chk_config () const |
479 | { |
482 | { |
480 | return prot_major == PROTOCOL_MAJOR |
483 | if (prot_major != PROTOCOL_MAJOR) |
481 | && randsize == RAND_SIZE |
484 | slog (L_WARN, _("major version mismatch (%d <=> %d)"), prot_major, PROTOCOL_MAJOR); |
482 | && hmaclen == HMACLENGTH |
485 | else if (randsize != RAND_SIZE) |
483 | && flags == curflags () |
486 | slog (L_WARN, _("rand size mismatch (%d <=> %d)"), randsize, RAND_SIZE); |
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487 | else if (hmaclen != HMACLENGTH) |
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488 | slog (L_WARN, _("hmac length mismatch (%d <=> %d)"), hmaclen, HMACLENGTH); |
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489 | else if (flags != curflags ()) |
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490 | slog (L_WARN, _("flag mismatch (%x <=> %x)"), flags, curflags ()); |
484 | && challengelen == sizeof (rsachallenge) |
491 | else if (challengelen != sizeof (rsachallenge)) |
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492 | slog (L_WARN, _("challenge length mismatch (%d <=> %d)"), challengelen, sizeof (rsachallenge)); |
485 | && cipher_nid == htonl (EVP_CIPHER_nid (CIPHER)) |
493 | else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER))) |
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|
494 | slog (L_WARN, _("cipher mismatch (%x <=> %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER)); |
486 | && digest_nid == htonl (EVP_MD_type (RSA_HASH)) |
495 | else if (digest_nid != htonl (EVP_MD_type (RSA_HASH))) |
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496 | slog (L_WARN, _("digest mismatch (%x <=> %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH)); |
487 | && hmac_nid == htonl (EVP_MD_type (DIGEST)); |
497 | else if (hmac_nid != htonl (EVP_MD_type (DIGEST))) |
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498 | slog (L_WARN, _("hmac mismatch (%x <=> %x)"), ntohl (hmac_nid), EVP_MD_type (DIGEST)); |
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499 | else |
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500 | return true; |
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501 | |
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502 | return false; |
488 | } |
503 | } |
489 | |
504 | |
490 | struct auth_req_packet : config_packet |
505 | struct auth_req_packet : config_packet |
491 | { |
506 | { |
492 | char magic[8]; |
507 | char magic[8]; |
… | |
… | |
565 | rekey.start (NOW + ::conf.rekey); |
580 | rekey.start (NOW + ::conf.rekey); |
566 | keepalive.start (NOW + ::conf.keepalive); |
581 | keepalive.start (NOW + ::conf.keepalive); |
567 | |
582 | |
568 | // send queued packets |
583 | // send queued packets |
569 | if (ictx && octx) |
584 | if (ictx && octx) |
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|
585 | { |
570 | while (tap_packet *p = queue.get ()) |
586 | while (tap_packet *p = (tap_packet *)data_queue.get ()) |
571 | { |
587 | { |
572 | send_data_packet (p); |
588 | send_data_packet (p); |
573 | delete p; |
589 | delete p; |
574 | } |
590 | } |
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591 | |
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592 | while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
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593 | { |
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594 | send_vpn_packet (p, si, IPTOS_RELIABILITY); |
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595 | delete p; |
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596 | } |
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597 | } |
575 | } |
598 | } |
576 | else |
599 | else |
577 | { |
600 | { |
578 | retry_cnt = 0; |
601 | retry_cnt = 0; |
579 | establish_connection.start (NOW + 5); |
602 | establish_connection.start (NOW + 5); |
… | |
… | |
778 | reset_connection (); |
801 | reset_connection (); |
779 | establish_connection (); |
802 | establish_connection (); |
780 | } |
803 | } |
781 | |
804 | |
782 | void |
805 | void |
783 | connection::send_data_packet (tap_packet *pkt, bool broadcast) |
806 | connection::send_data_packet (tap_packet *pkt) |
784 | { |
807 | { |
785 | vpndata_packet *p = new vpndata_packet; |
808 | vpndata_packet *p = new vpndata_packet; |
786 | int tos = 0; |
809 | int tos = 0; |
787 | |
810 | |
788 | if (conf->inherit_tos |
811 | // I am not hilarious about peeking into packets, but so be it. |
789 | && (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP |
812 | if (conf->inherit_tos && pkt->is_ipv4 ()) |
790 | && ((*pkt)[14] & 0xf0) == 0x40) // IPv4 |
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|
791 | tos = (*pkt)[15] & IPTOS_TOS_MASK; |
813 | tos = (*pkt)[15] & IPTOS_TOS_MASK; |
792 | |
814 | |
793 | p->setup (this, broadcast ? 0 : conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
815 | p->setup (this, conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
794 | send_vpn_packet (p, si, tos); |
816 | send_vpn_packet (p, si, tos); |
795 | |
817 | |
796 | delete p; |
818 | delete p; |
797 | |
819 | |
798 | if (oseqno > MAX_SEQNO) |
820 | if (oseqno > MAX_SEQNO) |
799 | rekey (); |
821 | rekey (); |
800 | } |
822 | } |
801 | |
823 | |
802 | void |
824 | void |
803 | connection::inject_data_packet (tap_packet *pkt, bool broadcast) |
825 | connection::inject_data_packet (tap_packet *pkt, bool broadcast/*TODO DDD*/) |
804 | { |
826 | { |
805 | if (ictx && octx) |
827 | if (ictx && octx) |
806 | send_data_packet (pkt, broadcast); |
828 | send_data_packet (pkt); |
807 | else |
829 | else |
808 | { |
830 | { |
809 | if (!broadcast)//DDDD |
831 | if (!broadcast)//DDDD |
810 | queue.put (new tap_packet (*pkt)); |
832 | data_queue.put (new tap_packet (*pkt)); |
811 | |
833 | |
812 | establish_connection (); |
834 | establish_connection (); |
813 | } |
835 | } |
814 | } |
836 | } |
815 | |
837 | |
816 | void connection::inject_vpn_packet (vpn_packet *pkt, int tos) |
838 | void connection::inject_vpn_packet (vpn_packet *pkt, int tos) |
817 | { |
839 | { |
818 | if (ictx && octx) |
840 | if (ictx && octx) |
819 | send_vpn_packet (pkt, si, tos); |
841 | send_vpn_packet (pkt, si, tos); |
820 | else |
842 | else |
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843 | { |
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844 | vpn_queue.put (new vpn_packet (*pkt)); |
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|
845 | |
821 | establish_connection (); |
846 | establish_connection (); |
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|
847 | } |
822 | } |
848 | } |
823 | |
849 | |
824 | void |
850 | void |
825 | connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
851 | connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
826 | { |
852 | { |
… | |
… | |
885 | rsachallenge k; |
911 | rsachallenge k; |
886 | |
912 | |
887 | if (0 > RSA_private_decrypt (sizeof (p->encr), |
913 | if (0 > RSA_private_decrypt (sizeof (p->encr), |
888 | (unsigned char *)&p->encr, (unsigned char *)&k, |
914 | (unsigned char *)&p->encr, (unsigned char *)&k, |
889 | ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
915 | ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
890 | slog (L_ERR, _("%s(%s): challenge illegal or corrupted"), |
916 | slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
891 | conf->nodename, (const char *)rsi); |
917 | conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
892 | else |
918 | else |
893 | { |
919 | { |
894 | delete octx; |
920 | delete octx; |
895 | |
921 | |
896 | octx = new crypto_ctx (k, 1); |
922 | octx = new crypto_ctx (k, 1); |
… | |
… | |
903 | connection_established (); |
929 | connection_established (); |
904 | |
930 | |
905 | break; |
931 | break; |
906 | } |
932 | } |
907 | } |
933 | } |
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|
934 | else |
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935 | slog (L_WARN, _("%s(%s): protocol mismatch"), |
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936 | conf->nodename, (const char *)rsi); |
908 | |
937 | |
909 | send_reset (rsi); |
938 | send_reset (rsi); |
910 | } |
939 | } |
911 | |
940 | |
912 | break; |
941 | break; |
… | |
… | |
925 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
954 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
926 | |
955 | |
927 | rsachallenge chg; |
956 | rsachallenge chg; |
928 | |
957 | |
929 | if (!rsa_cache.find (p->id, chg)) |
958 | if (!rsa_cache.find (p->id, chg)) |
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|
959 | { |
930 | slog (L_ERR, _("%s(%s): unrequested auth response"), |
960 | slog (L_ERR, _("%s(%s): unrequested auth response ignored"), |
931 | conf->nodename, (const char *)rsi); |
961 | conf->nodename, (const char *)rsi); |
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|
962 | break; |
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|
963 | } |
932 | else |
964 | else |
933 | { |
965 | { |
934 | crypto_ctx *cctx = new crypto_ctx (chg, 0); |
966 | crypto_ctx *cctx = new crypto_ctx (chg, 0); |
935 | |
967 | |
936 | if (!p->hmac_chk (cctx)) |
968 | if (!p->hmac_chk (cctx)) |
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|
969 | { |
937 | slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" |
970 | slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" |
938 | "could be an attack, or just corruption or an synchronization error"), |
971 | "could be an attack, or just corruption or an synchronization error"), |
939 | conf->nodename, (const char *)rsi); |
972 | conf->nodename, (const char *)rsi); |
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|
973 | break; |
|
|
974 | } |
940 | else |
975 | else |
941 | { |
976 | { |
942 | rsaresponse h; |
977 | rsaresponse h; |
943 | |
978 | |
944 | rsa_hash (p->id, chg, h); |
979 | rsa_hash (p->id, chg, h); |
… | |
… | |
1001 | |
1036 | |
1002 | if (iseqno.recv_ok (seqno)) |
1037 | if (iseqno.recv_ok (seqno)) |
1003 | { |
1038 | { |
1004 | vpn->tap->send (d); |
1039 | vpn->tap->send (d); |
1005 | |
1040 | |
1006 | if (p->dst () == 0) // re-broadcast |
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|
1007 | for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i) |
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|
1008 | { |
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1009 | connection *c = *i; |
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1010 | |
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1011 | if (c->conf != THISNODE && c->conf != conf) |
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1012 | c->inject_data_packet (d); |
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1013 | } |
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1014 | |
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1015 | if (si != rsi) |
1041 | if (si != rsi) |
1016 | { |
1042 | { |
1017 | // fast re-sync on conneciton changes, useful especially for tcp/ip |
1043 | // fast re-sync on connection changes, useful especially for tcp/ip |
1018 | si = rsi; |
1044 | si = rsi; |
1019 | |
1045 | |
1020 | slog (L_INFO, _("%s(%s): socket address changed to %s"), |
1046 | slog (L_INFO, _("%s(%s): socket address changed to %s"), |
1021 | conf->nodename, (const char *)si, (const char *)rsi); |
1047 | conf->nodename, (const char *)si, (const char *)rsi); |
1022 | } |
1048 | } |
… | |
… | |
1099 | || THISNODE->connectmode != conf_node::C_ONDEMAND) |
1125 | || THISNODE->connectmode != conf_node::C_ONDEMAND) |
1100 | { |
1126 | { |
1101 | send_ping (si); |
1127 | send_ping (si); |
1102 | w.at = NOW + 5; |
1128 | w.at = NOW + 5; |
1103 | } |
1129 | } |
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1130 | else if (NOW < last_activity + ::conf.keepalive + 10) |
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1131 | // hold ondemand connections implicitly a few seconds longer |
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1132 | // should delete octx, though, or something like that ;) |
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1133 | w.at = last_activity + ::conf.keepalive + 10; |
1104 | else |
1134 | else |
1105 | reset_connection (); |
1135 | reset_connection (); |
1106 | } |
1136 | } |
1107 | |
1137 | |
1108 | void connection::send_connect_request (int id) |
1138 | void connection::send_connect_request (int id) |