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 |
… | |
… | |
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]; |
… | |
… | |
786 | reset_connection (); |
801 | reset_connection (); |
787 | establish_connection (); |
802 | establish_connection (); |
788 | } |
803 | } |
789 | |
804 | |
790 | void |
805 | void |
791 | connection::send_data_packet (tap_packet *pkt, bool broadcast) |
806 | connection::send_data_packet (tap_packet *pkt) |
792 | { |
807 | { |
793 | vpndata_packet *p = new vpndata_packet; |
808 | vpndata_packet *p = new vpndata_packet; |
794 | int tos = 0; |
809 | int tos = 0; |
795 | |
810 | |
796 | // I am not hilarious about peeking into packets, but so be it. |
811 | // I am not hilarious about peeking into packets, but so be it. |
797 | if (conf->inherit_tos |
812 | if (conf->inherit_tos && pkt->is_ipv4 ()) |
798 | && (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP |
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799 | && ((*pkt)[14] & 0xf0) == 0x40) // IPv4 |
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800 | tos = (*pkt)[15] & IPTOS_TOS_MASK; |
813 | tos = (*pkt)[15] & IPTOS_TOS_MASK; |
801 | |
814 | |
802 | 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 |
803 | send_vpn_packet (p, si, tos); |
816 | send_vpn_packet (p, si, tos); |
804 | |
817 | |
805 | delete p; |
818 | delete p; |
806 | |
819 | |
807 | if (oseqno > MAX_SEQNO) |
820 | if (oseqno > MAX_SEQNO) |
808 | rekey (); |
821 | rekey (); |
809 | } |
822 | } |
810 | |
823 | |
811 | void |
824 | void |
812 | connection::inject_data_packet (tap_packet *pkt, bool broadcast) |
825 | connection::inject_data_packet (tap_packet *pkt, bool broadcast/*TODO DDD*/) |
813 | { |
826 | { |
814 | if (ictx && octx) |
827 | if (ictx && octx) |
815 | send_data_packet (pkt, broadcast); |
828 | send_data_packet (pkt); |
816 | else |
829 | else |
817 | { |
830 | { |
818 | if (!broadcast)//DDDD |
831 | if (!broadcast)//DDDD |
819 | data_queue.put (new tap_packet (*pkt)); |
832 | data_queue.put (new tap_packet (*pkt)); |
820 | |
833 | |
… | |
… | |
898 | rsachallenge k; |
911 | rsachallenge k; |
899 | |
912 | |
900 | if (0 > RSA_private_decrypt (sizeof (p->encr), |
913 | if (0 > RSA_private_decrypt (sizeof (p->encr), |
901 | (unsigned char *)&p->encr, (unsigned char *)&k, |
914 | (unsigned char *)&p->encr, (unsigned char *)&k, |
902 | ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
915 | ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
903 | 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?"), |
904 | conf->nodename, (const char *)rsi); |
917 | conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
905 | else |
918 | else |
906 | { |
919 | { |
907 | delete octx; |
920 | delete octx; |
908 | |
921 | |
909 | octx = new crypto_ctx (k, 1); |
922 | octx = new crypto_ctx (k, 1); |
… | |
… | |
916 | connection_established (); |
929 | connection_established (); |
917 | |
930 | |
918 | break; |
931 | break; |
919 | } |
932 | } |
920 | } |
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); |
921 | |
937 | |
922 | send_reset (rsi); |
938 | send_reset (rsi); |
923 | } |
939 | } |
924 | |
940 | |
925 | break; |
941 | break; |
… | |
… | |
938 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
954 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
939 | |
955 | |
940 | rsachallenge chg; |
956 | rsachallenge chg; |
941 | |
957 | |
942 | if (!rsa_cache.find (p->id, chg)) |
958 | if (!rsa_cache.find (p->id, chg)) |
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959 | { |
943 | slog (L_ERR, _("%s(%s): unrequested auth response"), |
960 | slog (L_ERR, _("%s(%s): unrequested auth response ignored"), |
944 | conf->nodename, (const char *)rsi); |
961 | conf->nodename, (const char *)rsi); |
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962 | break; |
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963 | } |
945 | else |
964 | else |
946 | { |
965 | { |
947 | crypto_ctx *cctx = new crypto_ctx (chg, 0); |
966 | crypto_ctx *cctx = new crypto_ctx (chg, 0); |
948 | |
967 | |
949 | if (!p->hmac_chk (cctx)) |
968 | if (!p->hmac_chk (cctx)) |
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969 | { |
950 | 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" |
951 | "could be an attack, or just corruption or an synchronization error"), |
971 | "could be an attack, or just corruption or an synchronization error"), |
952 | conf->nodename, (const char *)rsi); |
972 | conf->nodename, (const char *)rsi); |
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973 | break; |
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974 | } |
953 | else |
975 | else |
954 | { |
976 | { |
955 | rsaresponse h; |
977 | rsaresponse h; |
956 | |
978 | |
957 | rsa_hash (p->id, chg, h); |
979 | rsa_hash (p->id, chg, h); |
… | |
… | |
1014 | |
1036 | |
1015 | if (iseqno.recv_ok (seqno)) |
1037 | if (iseqno.recv_ok (seqno)) |
1016 | { |
1038 | { |
1017 | vpn->tap->send (d); |
1039 | vpn->tap->send (d); |
1018 | |
1040 | |
1019 | if (p->dst () == 0) // re-broadcast |
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1020 | for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i) |
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1021 | { |
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1022 | connection *c = *i; |
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1023 | |
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1024 | if (c->conf != THISNODE && c->conf != conf) |
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1025 | c->inject_data_packet (d); |
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1026 | } |
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1027 | |
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1028 | if (si != rsi) |
1041 | if (si != rsi) |
1029 | { |
1042 | { |
1030 | // fast re-sync on conneciton changes, useful especially for tcp/ip |
1043 | // fast re-sync on connection changes, useful especially for tcp/ip |
1031 | si = rsi; |
1044 | si = rsi; |
1032 | |
1045 | |
1033 | slog (L_INFO, _("%s(%s): socket address changed to %s"), |
1046 | slog (L_INFO, _("%s(%s): socket address changed to %s"), |
1034 | conf->nodename, (const char *)si, (const char *)rsi); |
1047 | conf->nodename, (const char *)si, (const char *)rsi); |
1035 | } |
1048 | } |