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Comparing gvpe/src/protocol.C (file contents):
Revision 1.18 by pcg, Wed Mar 26 02:15:38 2003 UTC vs.
Revision 1.19 by pcg, Wed Mar 26 14:39:52 2003 UTC

… …
82 EVP_CIPHER_CTX_cleanup (&cctx); 82 EVP_CIPHER_CTX_cleanup (&cctx);
83 HMAC_CTX_cleanup (&hctx); 83 HMAC_CTX_cleanup (&hctx);
84} 84}
85 85
86static void 86static void
87rsa_hash (const rsachallenge &chg, rsaresponse &h) 87rsa_hash (const rsaid &id, const rsachallenge &chg, rsaresponse &h)
88{ 88{
89 EVP_MD_CTX ctx; 89 EVP_MD_CTX ctx;
90 90
91 EVP_MD_CTX_init (&ctx); 91 EVP_MD_CTX_init (&ctx);
92 EVP_DigestInit (&ctx, RSA_HASH); 92 EVP_DigestInit (&ctx, RSA_HASH);
93 EVP_DigestUpdate(&ctx, &chg, sizeof chg); 93 EVP_DigestUpdate(&ctx, &chg, sizeof chg);
94 EVP_DigestUpdate(&ctx, &id, sizeof id);
94 EVP_DigestFinal (&ctx, (unsigned char *)&h, 0); 95 EVP_DigestFinal (&ctx, (unsigned char *)&h, 0);
95 EVP_MD_CTX_cleanup (&ctx); 96 EVP_MD_CTX_cleanup (&ctx);
96} 97}
97 98
98struct rsa_entry { 99struct rsa_entry {
… …
500 501
501#if ENABLE_COMPRESSION 502#if ENABLE_COMPRESSION
502 if (type == PT_DATA_COMPRESSED) 503 if (type == PT_DATA_COMPRESSED)
503 { 504 {
504 u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; 505 u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1];
506
505 p->len = lzf_decompress (d + DATAHDR + 2, cl, &(*p)[6 + 6], MAX_MTU) + 6 + 6; 507 p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0,
508 &(*p)[6 + 6], MAX_MTU)
509 + 6 + 6;
506 } 510 }
507 else 511 else
508 p->len = outl + (6 + 6 - DATAHDR); 512 p->len = outl + (6 + 6 - DATAHDR);
509#endif 513#endif
510 514
… …
583}; 587};
584 588
585struct auth_res_packet : config_packet 589struct auth_res_packet : config_packet
586{ 590{
587 rsaid id; 591 rsaid id;
592 u8 pad1, pad2, pad3;
593 u8 response_len; // encrypted length
588 rsaresponse response; 594 rsaresponse response;
589 595
590 auth_res_packet (int dst) 596 auth_res_packet (int dst)
591 { 597 {
592 config_packet::setup (PT_AUTH_RES, dst); 598 config_packet::setup (PT_AUTH_RES, dst);
… …
678} 684}
679 685
680void 686void
681connection::send_auth_request (SOCKADDR *sa, bool initiate) 687connection::send_auth_request (SOCKADDR *sa, bool initiate)
682{ 688{
683 if (auth_rate_limiter.can (sa)) 689 if (!initiate || auth_rate_limiter.can (sa))
684 { 690 {
685 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate); 691 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate);
686 692
687 rsachallenge chg; 693 rsachallenge chg;
688 694
… …
702} 708}
703 709
704void 710void
705connection::send_auth_response (SOCKADDR *sa, const rsaid &id, const rsachallenge &chg) 711connection::send_auth_response (SOCKADDR *sa, const rsaid &id, const rsachallenge &chg)
706{ 712{
707 if (auth_rate_limiter.can (sa))
708 {
709 auth_res_packet *pkt = new auth_res_packet (conf->id); 713 auth_res_packet *pkt = new auth_res_packet (conf->id);
710 714
711 pkt->id = id; 715 pkt->id = id;
716
712 rsa_hash (chg, pkt->response); 717 rsa_hash (id, chg, pkt->response);
713 718
719 pkt->hmac_set (octx);
720
714 slog (L_TRACE, ">>%d PT_AUTH_RES [%s]", conf->id, (const char *)sockinfo (sa)); 721 slog (L_TRACE, ">>%d PT_AUTH_RES [%s]", conf->id, (const char *)sockinfo (sa));
715 722
716 vpn->send_vpn_packet (pkt, sa, IPTOS_RELIABILITY); // rsa is very very costly 723 vpn->send_vpn_packet (pkt, sa, IPTOS_RELIABILITY); // rsa is very very costly
717 724
718 delete pkt; 725 delete pkt;
719 }
720} 726}
721 727
722void 728void
723connection::establish_connection_cb (tstamp &ts) 729connection::establish_connection_cb (tstamp &ts)
724{ 730{
… …
752void 758void
753connection::reset_connection () 759connection::reset_connection ()
754{ 760{
755 if (ictx && octx) 761 if (ictx && octx)
756 { 762 {
757 slog (L_INFO, _("connection to %d (%s) lost"), conf->id, conf->nodename); 763 slog (L_INFO, _("%s(%s): connection lost"),
764 conf->nodename, (const char *)sockinfo (sa));
758 765
759 if (::conf.script_node_down) 766 if (::conf.script_node_down)
760 run_script (run_script_cb (this, &connection::script_node_down), false); 767 run_script (run_script_cb (this, &connection::script_node_down), false);
761 } 768 }
762 769
… …
859 866
860 config_packet *p = (config_packet *) pkt; 867 config_packet *p = (config_packet *) pkt;
861 868
862 if (!p->chk_config ()) 869 if (!p->chk_config ())
863 { 870 {
864 slog (L_WARN, _("protocol mismatch, disabling node '%s'"), conf->nodename); 871 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"),
872 conf->nodename, (const char *)sockinfo (ssa));
865 connectmode = conf_node::C_DISABLED; 873 connectmode = conf_node::C_DISABLED;
866 } 874 }
867 else if (connectmode == conf_node::C_ALWAYS) 875 else if (connectmode == conf_node::C_ALWAYS)
868 establish_connection (); 876 establish_connection ();
869 } 877 }
870 break; 878 break;
871 879
872 case vpn_packet::PT_AUTH_REQ: 880 case vpn_packet::PT_AUTH_REQ:
881 if (auth_rate_limiter.can (ssa))
882 {
883 auth_req_packet *p = (auth_req_packet *) pkt;
884
885 slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate);
886
887 if (p->chk_config () && !strncmp (p->magic, MAGIC, 8))
888 {
889 if (p->prot_minor != PROTOCOL_MINOR)
890 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
891 conf->nodename, (const char *)sockinfo (ssa),
892 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
893
894 if (p->initiate)
895 send_auth_request (ssa, false);
896
897 rsachallenge k;
898
899 if (0 > RSA_private_decrypt (sizeof (p->encr),
900 (unsigned char *)&p->encr, (unsigned char *)&k,
901 ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING))
902 slog (L_ERR, _("%s(%s): challenge illegal or corrupted"),
903 conf->nodename, (const char *)sockinfo (ssa));
904 else
905 {
906 retry_cnt = 0;
907 establish_connection.set (NOW + 8); //? ;)
908 keepalive.reset ();
909 rekey.reset ();
910
911 delete ictx;
912 ictx = 0;
913
914 delete octx;
915
916 octx = new crypto_ctx (k, 1);
917 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff;
918
919 send_auth_response (ssa, p->id, k);
920
921 break;
922 }
923 }
924
925 send_reset (ssa);
926 }
927
928 break;
929
930 case vpn_packet::PT_AUTH_RES:
873 { 931 {
874 auth_req_packet *p = (auth_req_packet *) pkt; 932 auth_res_packet *p = (auth_res_packet *) pkt;
875 933
876 slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate); 934 slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id);
877 935
878 if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) 936 if (p->chk_config ())
879 { 937 {
880 if (p->prot_minor != PROTOCOL_MINOR) 938 if (p->prot_minor != PROTOCOL_MINOR)
881 slog (L_INFO, _("protocol minor version mismatch: ours is %d, %s's is %d."), 939 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
940 conf->nodename, (const char *)sockinfo (ssa),
882 PROTOCOL_MINOR, conf->nodename, p->prot_minor); 941 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
883 942
884 if (p->initiate)
885 send_auth_request (ssa, false);
886
887 rsachallenge k; 943 rsachallenge chg;
888 944
889 if (0 > RSA_private_decrypt (sizeof (p->encr), 945 if (!rsa_cache.find (p->id, chg))
890 (unsigned char *)&p->encr, (unsigned char *)&k, 946 slog (L_ERR, _("%s(%s): unrequested auth response"),
891 ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING))
892 slog (L_ERR, _("challenge from %s (%s) illegal or corrupted"),
893 conf->nodename, (const char *)sockinfo (ssa)); 947 conf->nodename, (const char *)sockinfo (ssa));
894 else 948 else
895 { 949 {
896 retry_cnt = 0; 950 crypto_ctx *cctx = new crypto_ctx (chg, 0);
897 establish_connection.set (NOW + 8); //? ;)
898 keepalive.reset ();
899 rekey.reset ();
900 951
901 delete ictx; 952 if (!p->hmac_chk (cctx))
902 ictx = 0; 953 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n"
903 954 "could be an attack, or just corruption or an synchronization error"),
904 delete octx;
905
906 octx = new crypto_ctx (k, 1);
907 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff;
908
909 send_auth_response (ssa, p->id, k);
910
911 break;
912 }
913 }
914 }
915
916 send_reset (ssa);
917 break;
918
919 case vpn_packet::PT_AUTH_RES:
920 {
921 auth_res_packet *p = (auth_res_packet *) pkt;
922
923 slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id);
924
925 if (p->chk_config ())
926 {
927 if (p->prot_minor != PROTOCOL_MINOR)
928 slog (L_INFO, _("protocol minor version mismatch: ours is %d, %s's is %d."),
929 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
930
931 rsachallenge chg;
932
933 if (!rsa_cache.find (p->id, chg))
934 slog (L_ERR, _("unrequested auth response from %s (%s)"),
935 conf->nodename, (const char *)sockinfo (ssa)); 955 conf->nodename, (const char *)sockinfo (ssa));
936 else 956 else
937 {
938 rsaresponse h;
939
940 rsa_hash (chg, h);
941
942 if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h))
943 { 957 {
944 delete ictx;
945
946 ictx = new crypto_ctx (chg, 0);
947 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
948
949 sa = *ssa; 958 rsaresponse h;
950 959
951 rekey.set (NOW + ::conf.rekey); 960 rsa_hash (p->id, chg, h);
952 keepalive.set (NOW + ::conf.keepalive);
953 961
954 // send queued packets 962 if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h))
955 while (tap_packet *p = queue.get ())
956 { 963 {
964 prot_minor = p->prot_minor;
965
966 delete ictx; ictx = cctx;
967
968 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
969
970 sa = *ssa;
971
972 rekey.set (NOW + ::conf.rekey);
973 keepalive.set (NOW + ::conf.keepalive);
974
975 // send queued packets
976 while (tap_packet *p = queue.get ())
977 {
957 send_data_packet (p); 978 send_data_packet (p);
958 delete p; 979 delete p;
980 }
981
982 connectmode = conf->connectmode;
983
984 slog (L_INFO, _("%s(%s): connection established, protocol version %d:%d"),
985 conf->nodename, (const char *)sockinfo (ssa),
986 p->prot_major, p->prot_minor);
987
988 if (::conf.script_node_up)
989 run_script (run_script_cb (this, &connection::script_node_up), false);
990
991 break;
959 } 992 }
960 993 else
961 connectmode = conf->connectmode; 994 slog (L_ERR, _("%s(%s): sent and received challenge do not match"),
962
963 slog (L_INFO, _("connection to %d (%s %s) established"),
964 conf->id, conf->nodename, (const char *)sockinfo (ssa)); 995 conf->nodename, (const char *)sockinfo (ssa));
965
966 if (::conf.script_node_up)
967 run_script (run_script_cb (this, &connection::script_node_up), false);
968
969 break;
970 } 996 }
997
971 else 998 delete cctx;
972 slog (L_ERR, _("sent and received challenge do not match with (%s %s))"),
973 conf->nodename, (const char *)sockinfo (ssa));
974 } 999 }
975 } 1000 }
976 } 1001 }
977 1002
978 send_reset (ssa); 1003 send_reset (ssa);
… …
991 vpndata_packet *p = (vpndata_packet *)pkt; 1016 vpndata_packet *p = (vpndata_packet *)pkt;
992 1017
993 if (*ssa == sa) 1018 if (*ssa == sa)
994 { 1019 {
995 if (!p->hmac_chk (ictx)) 1020 if (!p->hmac_chk (ictx))
996 slog (L_ERR, _("hmac authentication error, received invalid packet\n" 1021 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n"
997 "could be an attack, or just corruption or an synchronization error")); 1022 "could be an attack, or just corruption or an synchronization error"),
1023 conf->nodename, (const char *)sockinfo (ssa));
998 else 1024 else
999 { 1025 {
1000 u32 seqno; 1026 u32 seqno;
1001 tap_packet *d = p->unpack (this, seqno); 1027 tap_packet *d = p->unpack (this, seqno);
1002 1028

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