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/* |
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connection.h -- header for connection.C |
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Copyright (C) 2003-2008,2013 Marc Lehmann <gvpe@schmorp.de> |
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|
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This file is part of GVPE. |
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|
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GVPE is free software; you can redistribute it and/or modify it |
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under the terms of the GNU General Public License as published by the |
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Free Software Foundation; either version 3 of the License, or (at your |
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option) any later version. |
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|
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This program is distributed in the hope that it will be useful, but |
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WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General |
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Public License for more details. |
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|
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You should have received a copy of the GNU General Public License along |
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with this program; if not, see <http://www.gnu.org/licenses/>. |
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|
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Additional permission under GNU GPL version 3 section 7 |
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|
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If you modify this Program, or any covered work, by linking or |
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combining it with the OpenSSL project's OpenSSL library (or a modified |
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version of that library), containing parts covered by the terms of the |
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OpenSSL or SSLeay licenses, the licensors of this Program grant you |
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additional permission to convey the resulting work. Corresponding |
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Source for a non-source form of such a combination shall include the |
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source code for the parts of OpenSSL used as well as that of the |
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covered work. |
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*/ |
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|
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#ifndef GVPE_CONNECTION_H__ |
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#define GVPE_CONNECTION_H__ |
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|
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#include <openssl/hmac.h> |
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|
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#include "global.h" |
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#include "conf.h" |
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#include "sockinfo.h" |
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#include "util.h" |
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#include "device.h" |
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#include "curve25519.h" |
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#include "iv_gen.h" |
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|
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struct vpn; |
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|
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// called after HUP etc. to (re-)initialize global data structures |
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void connection_init (); |
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|
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typedef curve25519_key ecdh_key; |
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|
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struct rsa_data |
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{ |
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u32 seqno; // (ictx) initial sequence nr (31 bits) |
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u8 mac_key[MAC_IKMSIZE]; // (ictx) used to generate hmac key |
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u8 cipher_key[CIPHER_IKMSIZE]; // (ictx) used to generate cipher key |
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u8 hkdf_salt[HKDF_SALT]; // (octx) used as hkdf salt |
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u8 extra_auth[ // (ictx) additional auth randomness |
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(RSABITS >> 3) |
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- RSA_OAEP_SIZE |
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- sizeof (u32) // seqno |
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- MAC_IKMSIZE |
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- CIPHER_IKMSIZE |
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- HKDF_SALT |
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- 3 // struct alignment... |
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]; |
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}; |
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|
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struct auth_data |
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{ |
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rsa_data rsa; |
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ecdh_key ecdh; |
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}; |
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|
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typedef u8 rsa_crypt[RSA_KEYLEN]; // encrypted challenge |
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|
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struct auth_encr |
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{ |
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rsa_crypt rsa; |
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ecdh_key ecdh; |
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}; |
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|
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typedef u8 auth_mac[AUTH_SIZE]; |
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|
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struct auth_response |
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{ |
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auth_mac mac; |
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ecdh_key ecdh; |
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}; |
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|
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//////////////////////////////////////////////////////////////////////////////////////// |
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|
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struct crypto_ctx; |
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|
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struct hmac_packet : net_packet |
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{ |
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u8 hmac[HMACLENGTH]; // each and every packet has a hmac field, but that is not (yet) checked everywhere |
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|
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void hmac_set (crypto_ctx * ctx); |
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bool hmac_chk (crypto_ctx * ctx); |
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|
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private: |
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void hmac_gen (crypto_ctx * ctx, u8 *hmac_digest); |
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}; |
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|
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struct vpn_packet : hmac_packet |
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{ |
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enum ptype |
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{ |
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PT_RESET = 0, |
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PT_DATA_UNCOMPRESSED, |
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PT_DATA_COMPRESSED, |
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PT_PING, PT_PONG, // wasting namespace space? ;) |
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PT_AUTH_REQ, // authentification request |
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PT_AUTH_RES, // authentification response |
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PT_CONNECT_REQ, // want other node to contact me |
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PT_CONNECT_INFO, // request connection to some node |
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PT_DATA_BRIDGED, // uncompressed packet with foreign mac pot. larger than path mtu (NYI) |
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PT_MAX |
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}; |
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|
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u8 type; |
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u8 srcdst, src1, dst1; |
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|
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void set_hdr (ptype type_, unsigned int dst); |
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|
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unsigned int src () const |
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{ |
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return src1 | ((srcdst >> 4) << 8); |
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} |
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|
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unsigned int dst () const |
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{ |
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return dst1 | ((srcdst & 0xf) << 8); |
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} |
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|
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ptype typ () const |
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{ |
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return (ptype) type; |
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} |
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}; |
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|
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//////////////////////////////////////////////////////////////////////////////////////// |
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|
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// a very simple fifo pkt-queue |
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class pkt_queue |
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{ |
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int i, j; |
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int max_queue; |
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double max_ttl; |
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|
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struct pkt { |
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ev_tstamp tstamp; |
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net_packet *pkt; |
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} *queue; |
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|
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void expire_cb (ev::timer &w, int revents); ev::timer expire; |
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|
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public: |
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|
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void put (net_packet *p); |
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net_packet *get (); |
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|
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bool empty () |
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{ |
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return i == j; |
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} |
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|
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pkt_queue (double max_ttl, int max_queue); |
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~pkt_queue (); |
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}; |
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|
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enum |
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{ |
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FEATURE_COMPRESSION = 0x01, |
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FEATURE_ROHC = 0x02, |
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FEATURE_BRIDGING = 0x04, |
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}; |
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|
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struct connection |
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{ |
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conf_node *conf; |
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struct vpn *vpn; |
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|
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sockinfo si; // the current(!) destination ip to send packets to |
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int retry_cnt; |
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|
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tstamp last_activity; // time of last packet received |
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tstamp last_establish_attempt; |
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//tstamp last_si_change; // time we last changed the socket address |
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|
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u32 oseqno; |
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sliding_window iseqno; |
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|
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u8 protocol; |
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u8 features; |
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bool is_direct; // current connection (si) is direct? |
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|
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pkt_queue data_queue, vpn_queue; |
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|
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crypto_ctx *octx, *ictx; |
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iv_gen oiv; // generator for random byte prefix |
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|
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void generate_auth_data (); |
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|
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ev_tstamp auth_expire; // when the snd_* and *_ecdh values expire |
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|
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// send auth data - used for octx |
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auth_data snd_auth; |
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ecdh_key snd_ecdh_a; // the secret ecdh key we used for our request |
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ecdh_key snd_ecdh_b; // the public ecdh key we received in the response |
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bool have_snd_auth; // received response for our req |
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|
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// receive auth data - used for ictx |
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auth_data rcv_auth; |
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ecdh_key rcv_ecdh_a; // the secret ecdh key we used for our response |
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ecdh_key rcv_ecdh_b; // the public ecdh key we sent in our response |
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bool have_rcv_auth; // received auth from other side |
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|
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#if ENABLE_DNS |
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struct dns_connection *dns; |
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#endif |
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|
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enum conf_node::connectmode connectmode; |
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u8 prot_minor; // minor number of other side |
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|
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void reset_si (); |
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const sockinfo &forward_si (const sockinfo &si) const; |
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|
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void shutdown (); |
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void connection_established (const sockinfo &rsi); |
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void reset_connection (); |
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|
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void establish_connection_cb (ev::timer &w, int revents); ev::timer establish_connection; |
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void rekey_cb (ev::timer &w, int revents); ev::timer rekey; // next rekying (actually current reset + reestablishing) |
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void keepalive_cb (ev::timer &w, int revents); ev::timer keepalive; // next keepalive probe |
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|
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void send_connect_request (int id); |
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void send_auth_request (const sockinfo &si, bool initiate); |
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void send_auth_response (const sockinfo &si); |
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void send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols); |
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void send_reset (const sockinfo &dsi); |
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void send_ping (const sockinfo &dsi, u8 pong = 0); |
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void send_data_packet (tap_packet *pkt); |
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|
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void post_inject_queue (); |
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void inject_data_packet (tap_packet *pkt); |
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void inject_vpn_packet (vpn_packet *pkt, int tos = 0); // for forwarding |
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|
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void recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi); |
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void send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos = 0); |
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|
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void script_init_env (const char *ext); |
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void script_init_connect_env (); |
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const char *script_node_up (); |
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const char *script_node_change (); |
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const char *script_node_down (); |
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|
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void dump_status (); |
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|
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connection (struct vpn *vpn, conf_node *conf); |
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~connection (); |
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}; |
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|
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#endif |
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