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/* |
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connection.C -- manage a single connection |
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Copyright (C) 2003-2008,2010,2011,2013,2016 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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#include "config.h" |
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|
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#include <list> |
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#include <queue> |
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#include <utility> |
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|
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#include <openssl/opensslv.h> |
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#include <openssl/rand.h> |
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#include <openssl/evp.h> |
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#include <openssl/rsa.h> |
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#include <openssl/err.h> |
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|
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#include "conf.h" |
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#include "slog.h" |
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#include "crypto.h" |
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#include "device.h" |
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#include "vpn.h" |
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#include "connection.h" |
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#include "hkdf.h" |
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|
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#include "netcompat.h" |
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|
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#define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic |
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|
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#define ULTRA_FAST 1 |
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#define HLOG 15 |
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#include "lzf/lzf.h" |
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#include "lzf/lzf_c.c" |
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#include "lzf/lzf_d.c" |
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|
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////////////////////////////////////////////////////////////////////////////// |
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|
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static std::queue< std::pair<run_script_cb *, const char *> > rs_queue; |
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static ev::child rs_child_ev; |
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|
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namespace |
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{ |
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void // c++ requires external linkage here, apparently :( |
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rs_child_cb (ev::child &w, int revents) |
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{ |
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w.stop (); |
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|
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if (rs_queue.empty ()) |
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return; |
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|
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pid_t pid = run_script (*rs_queue.front ().first, false); |
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if (pid) |
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{ |
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w.set (pid); |
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w.start (); |
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} |
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else |
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slog (L_WARN, rs_queue.front ().second); |
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|
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delete rs_queue.front ().first; |
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rs_queue.pop (); |
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} |
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}; |
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|
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// despite the fancy name, this is quite a hack |
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static void |
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run_script_queued (run_script_cb *cb, const char *warnmsg) |
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{ |
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rs_queue.push (std::make_pair (cb, warnmsg)); |
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|
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if (!rs_child_ev.is_active ()) |
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{ |
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rs_child_ev.set<rs_child_cb> (); |
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rs_child_ev (); |
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} |
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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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EVP_CIPHER_CTX cctx; |
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hmac hctx; |
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|
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crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc); |
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~crypto_ctx (); |
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}; |
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|
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crypto_ctx::crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc) |
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{ |
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ecdh_key s; |
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|
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curve25519_combine (a, b, s); |
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|
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{ |
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u8 mac_key[MAC_KEYSIZE]; |
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static const unsigned char mac_info[] = "gvpe mac key"; |
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|
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hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ()); |
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kdf.extract (auth1.rsa.mac_key, sizeof (auth1.rsa.mac_key)); |
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kdf.extract (s, sizeof (s)); |
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kdf.extract_done (HKDF_PRF_HASH ()); |
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kdf.expand (mac_key, sizeof (mac_key), mac_info, sizeof (mac_info)); |
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|
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hctx.init (mac_key, MAC_KEYSIZE, MAC_DIGEST ()); |
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} |
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|
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{ |
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u8 cipher_key[CIPHER_KEYSIZE]; |
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static const unsigned char cipher_info[] = "gvpe cipher key"; |
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|
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hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ()); |
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kdf.extract (auth1.rsa.cipher_key, sizeof (auth1.rsa.cipher_key)); |
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kdf.extract (s, sizeof (s)); |
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kdf.extract_done (HKDF_PRF_HASH ()); |
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kdf.expand (cipher_key, sizeof (cipher_key), cipher_info, sizeof (cipher_info)); |
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|
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EVP_CIPHER_CTX_init (&cctx); |
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require (EVP_CipherInit_ex (&cctx, CIPHER (), 0, cipher_key, 0, enc)); |
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} |
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} |
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|
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crypto_ctx::~crypto_ctx () |
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{ |
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require (EVP_CIPHER_CTX_cleanup (&cctx)); |
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} |
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|
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static inline void |
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auth_encrypt (RSA *key, const auth_data &auth, auth_encr &encr) |
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{ |
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if (RSA_public_encrypt (sizeof (auth.rsa), |
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(unsigned char *)&auth.rsa, (unsigned char *)&encr.rsa, |
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key, RSA_PKCS1_OAEP_PADDING) < 0) |
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fatal ("RSA_public_encrypt error"); |
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|
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memcpy (&encr.ecdh, &auth.ecdh, sizeof (encr.ecdh)); |
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} |
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|
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static inline bool |
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auth_decrypt (RSA *key, const auth_encr &encr, auth_data &auth) |
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{ |
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u8 rsa_decrypt[RSA_KEYLEN]; |
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|
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if (RSA_private_decrypt (sizeof (encr.rsa), |
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(const unsigned char *)&encr.rsa, (unsigned char *)rsa_decrypt, |
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key, RSA_PKCS1_OAEP_PADDING) != sizeof (auth.rsa)) |
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return 0; |
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|
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memcpy (&auth.rsa, rsa_decrypt, sizeof (auth.rsa)); |
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memcpy (&auth.ecdh, &encr.ecdh, sizeof (auth.ecdh)); |
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|
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return 1; |
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} |
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|
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static void |
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auth_hash (const auth_data &auth, const ecdh_key &b, auth_mac &mac) |
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{ |
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hkdf kdf (b, sizeof b, AUTH_DIGEST ()); // use response ecdh b as salt |
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kdf.extract (&auth.rsa, sizeof (auth.rsa)); |
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kdf.extract_done (); |
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kdf.expand (mac, sizeof mac, auth.ecdh, sizeof (auth.ecdh)); // use challenge ecdh b as info |
188 |
} |
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|
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void |
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connection::generate_auth_data () |
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{ |
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if (auth_expire < ev_now ()) |
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{ |
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// request data |
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rand_fill (snd_auth.rsa); |
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curve25519_generate (snd_ecdh_a, snd_auth.ecdh); |
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|
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// eventual response data |
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curve25519_generate (rcv_ecdh_a, rcv_ecdh_b); |
201 |
} |
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|
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// every use prolongs the expiry |
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auth_expire = ev_now () + AUTH_TTL; |
205 |
} |
206 |
|
207 |
////////////////////////////////////////////////////////////////////////////// |
208 |
|
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pkt_queue::pkt_queue (double max_ttl, int max_queue) |
210 |
: max_ttl (max_ttl), max_queue (max_queue) |
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{ |
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queue = new pkt [max_queue]; |
213 |
|
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i = 0; |
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j = 0; |
216 |
|
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expire.set<pkt_queue, &pkt_queue::expire_cb> (this); |
218 |
} |
219 |
|
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pkt_queue::~pkt_queue () |
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{ |
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while (net_packet *p = get ()) |
223 |
delete p; |
224 |
|
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delete [] queue; |
226 |
} |
227 |
|
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void |
229 |
pkt_queue::expire_cb (ev::timer &w, int revents) |
230 |
{ |
231 |
ev_tstamp expire = ev_now () - max_ttl; |
232 |
|
233 |
for (;;) |
234 |
{ |
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if (empty ()) |
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break; |
237 |
|
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double diff = queue[j].tstamp - expire; |
239 |
|
240 |
if (diff >= 0.) |
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{ |
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w.start (diff > 0.5 ? diff : 0.5); |
243 |
break; |
244 |
} |
245 |
|
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delete get (); |
247 |
} |
248 |
} |
249 |
|
250 |
void |
251 |
pkt_queue::put (net_packet *p) |
252 |
{ |
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ev_tstamp now = ev_now (); |
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|
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// start expiry timer |
256 |
if (empty ()) |
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expire.start (max_ttl); |
258 |
|
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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 |
|
270 |
net_packet * |
271 |
pkt_queue::get () |
272 |
{ |
273 |
if (empty ()) |
274 |
return 0; |
275 |
|
276 |
net_packet *p = queue[j].pkt; |
277 |
queue[j].pkt = 0; |
278 |
|
279 |
j = j + 1 == max_queue ? 0 : j + 1; |
280 |
|
281 |
return p; |
282 |
} |
283 |
|
284 |
struct net_rateinfo |
285 |
{ |
286 |
u32 host; |
287 |
double pcnt, diff; |
288 |
tstamp last; |
289 |
}; |
290 |
|
291 |
// only do action once every x seconds per host whole allowing bursts. |
292 |
// this implementation ("splay list" ;) is inefficient, |
293 |
// but low on resources. |
294 |
struct net_rate_limiter : list<net_rateinfo> |
295 |
{ |
296 |
# define NRL_ALPHA (1. - 1. / 600.) // allow bursts |
297 |
# define NRL_CUTOFF 10. // one event every CUTOFF seconds |
298 |
# define NRL_EXPIRE (NRL_CUTOFF * 30.) // expire entries after this time |
299 |
# define NRL_MAXDIF (NRL_CUTOFF * (1. / (1. - NRL_ALPHA))) // maximum diff /count value |
300 |
|
301 |
bool can (const sockinfo &si) { return can((u32)si.host); } |
302 |
bool can (u32 host); |
303 |
}; |
304 |
|
305 |
static net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
306 |
|
307 |
bool |
308 |
net_rate_limiter::can (u32 host) |
309 |
{ |
310 |
iterator i; |
311 |
|
312 |
for (i = begin (); i != end (); ) |
313 |
if (i->host == host) |
314 |
break; |
315 |
else if (i->last < ev_now () - NRL_EXPIRE) |
316 |
i = erase (i); |
317 |
else |
318 |
i++; |
319 |
|
320 |
if (i == end ()) |
321 |
{ |
322 |
net_rateinfo ri; |
323 |
|
324 |
ri.host = host; |
325 |
ri.pcnt = 1.; |
326 |
ri.diff = NRL_MAXDIF; |
327 |
ri.last = ev_now (); |
328 |
|
329 |
push_front (ri); |
330 |
|
331 |
return true; |
332 |
} |
333 |
else |
334 |
{ |
335 |
net_rateinfo ri (*i); |
336 |
erase (i); |
337 |
|
338 |
ri.pcnt = ri.pcnt * NRL_ALPHA; |
339 |
ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last); |
340 |
|
341 |
ri.last = ev_now (); |
342 |
|
343 |
double dif = ri.diff / ri.pcnt; |
344 |
|
345 |
bool send = dif > NRL_CUTOFF; |
346 |
|
347 |
if (dif > NRL_MAXDIF) |
348 |
{ |
349 |
ri.pcnt = 1.; |
350 |
ri.diff = NRL_MAXDIF; |
351 |
} |
352 |
else if (send) |
353 |
ri.pcnt++; |
354 |
|
355 |
push_front (ri); |
356 |
|
357 |
return send; |
358 |
} |
359 |
} |
360 |
|
361 |
///////////////////////////////////////////////////////////////////////////// |
362 |
|
363 |
void |
364 |
hmac_packet::hmac_gen (crypto_ctx *ctx, u8 *hmac_digest) |
365 |
{ |
366 |
ctx->hctx.init (); |
367 |
ctx->hctx.add (((unsigned char *) this) + sizeof (hmac_packet), len - sizeof (hmac_packet)); |
368 |
ctx->hctx.digest (hmac_digest); |
369 |
} |
370 |
|
371 |
void |
372 |
hmac_packet::hmac_set (crypto_ctx *ctx) |
373 |
{ |
374 |
unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
375 |
hmac_gen (ctx, hmac_digest); |
376 |
memcpy (hmac, hmac_digest, HMACLENGTH); |
377 |
} |
378 |
|
379 |
bool |
380 |
hmac_packet::hmac_chk (crypto_ctx *ctx) |
381 |
{ |
382 |
unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
383 |
hmac_gen (ctx, hmac_digest); |
384 |
return slow_memeq (hmac, hmac_digest, HMACLENGTH); |
385 |
} |
386 |
|
387 |
void |
388 |
vpn_packet::set_hdr (ptype type_, unsigned int dst) |
389 |
{ |
390 |
type = type_; |
391 |
|
392 |
int src = THISNODE->id; |
393 |
|
394 |
src1 = src; |
395 |
srcdst = ((src >> 8) << 4) | (dst >> 8); |
396 |
dst1 = dst; |
397 |
} |
398 |
|
399 |
#define MAXVPNDATA (MAX_MTU - 6 - 6) |
400 |
|
401 |
struct vpndata_packet : vpn_packet |
402 |
{ |
403 |
u32 ctr; // seqno |
404 |
u8 data[MAXVPNDATA]; |
405 |
|
406 |
void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno); |
407 |
tap_packet *unpack (connection *conn, u32 &seqno); |
408 |
|
409 |
private: |
410 |
const u32 data_hdr_size () const |
411 |
{ |
412 |
// the distance from beginning of packet to data member |
413 |
return data - at (0); |
414 |
} |
415 |
}; |
416 |
|
417 |
// expands packet counter (unlike seqno, in network byte order) to counter mode IV |
418 |
static unsigned char * |
419 |
expand_iv (u32 ctr) |
420 |
{ |
421 |
static u32 iv[IV_SIZE (CIPHER) / 4]; |
422 |
|
423 |
require (sizeof (iv) == 4 * 4); |
424 |
require (IV_SIZE (CIPHER) % 4 == 0); |
425 |
|
426 |
iv[0] = |
427 |
iv[1] = |
428 |
iv[2] = ctr; |
429 |
|
430 |
// I would reuse ctr here to to avoid potential endianness issues, |
431 |
// but it seems openssl wraps around. While this would be still ok, |
432 |
// and I don't even know if its true, let's play safe and initialise |
433 |
// to 0. |
434 |
iv[3] = 0; |
435 |
|
436 |
return (unsigned char *)iv; |
437 |
} |
438 |
|
439 |
void |
440 |
vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
441 |
{ |
442 |
EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
443 |
int outl = 0, outl2; |
444 |
ptype type = PT_DATA_UNCOMPRESSED; |
445 |
|
446 |
#if ENABLE_COMPRESSION |
447 |
u8 cdata[MAX_MTU]; |
448 |
|
449 |
if (conn->features & FEATURE_COMPRESSION) |
450 |
{ |
451 |
u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
452 |
|
453 |
if (cl) |
454 |
{ |
455 |
type = PT_DATA_COMPRESSED; |
456 |
d = cdata; |
457 |
l = cl + 2; |
458 |
|
459 |
d[0] = cl >> 8; |
460 |
d[1] = cl; |
461 |
} |
462 |
} |
463 |
#endif |
464 |
|
465 |
ctr = htonl (seqno); |
466 |
|
467 |
require (EVP_EncryptInit_ex (cctx, 0, 0, 0, expand_iv (ctr))); |
468 |
|
469 |
require (EVP_EncryptUpdate (cctx, |
470 |
(unsigned char *)data + outl, &outl2, |
471 |
(unsigned char *)d, l)); |
472 |
outl += outl2; |
473 |
|
474 |
// it seems this is a nop for us, but we do it anyways |
475 |
require (EVP_EncryptFinal_ex (cctx, (unsigned char *)data + outl, &outl2)); |
476 |
outl += outl2; |
477 |
|
478 |
len = data_hdr_size () + outl; |
479 |
|
480 |
set_hdr (type, dst); |
481 |
|
482 |
hmac_set (conn->octx); |
483 |
} |
484 |
|
485 |
tap_packet * |
486 |
vpndata_packet::unpack (connection *conn, u32 &seqno) |
487 |
{ |
488 |
EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; |
489 |
int outl = 0, outl2; |
490 |
tap_packet *p = new tap_packet; |
491 |
u8 *d; |
492 |
|
493 |
seqno = ntohl (ctr); |
494 |
|
495 |
require (EVP_DecryptInit_ex (cctx, 0, 0, 0, expand_iv (ctr))); |
496 |
|
497 |
#if ENABLE_COMPRESSION |
498 |
u8 cdata[MAX_MTU]; |
499 |
|
500 |
if (type == PT_DATA_COMPRESSED) |
501 |
d = cdata; |
502 |
else |
503 |
#endif |
504 |
d = &(*p)[6 + 6]; |
505 |
|
506 |
// this can overwrite the len/dst/src fields |
507 |
require (EVP_DecryptUpdate (cctx, |
508 |
d, &outl2, |
509 |
(unsigned char *)&data, len - data_hdr_size ())); |
510 |
outl += outl2; |
511 |
|
512 |
// it seems this is a nop for us, but we do it anyways |
513 |
require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2)); |
514 |
outl += outl2; |
515 |
|
516 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
517 |
id2mac (src (), p->src); |
518 |
|
519 |
#if ENABLE_COMPRESSION |
520 |
if (type == PT_DATA_COMPRESSED) |
521 |
{ |
522 |
u32 cl = (d[0] << 8) | d[1]; |
523 |
|
524 |
p->len = lzf_decompress (d + 2, cl < MAX_MTU - 2 ? cl : 0, |
525 |
&(*p)[6 + 6], MAX_MTU) |
526 |
+ 6 + 6; |
527 |
} |
528 |
else |
529 |
p->len = outl + (6 + 6); |
530 |
#endif |
531 |
|
532 |
return p; |
533 |
} |
534 |
|
535 |
struct ping_packet : vpn_packet |
536 |
{ |
537 |
void setup (int dst, ptype type) |
538 |
{ |
539 |
set_hdr (type, dst); |
540 |
len = sizeof (*this) - sizeof (net_packet); |
541 |
} |
542 |
}; |
543 |
|
544 |
struct config_packet : vpn_packet |
545 |
{ |
546 |
u8 serial[SERIAL_SIZE]; |
547 |
u8 prot_major, prot_minor, randsize; |
548 |
u8 flags, features, pad6, pad7, pad8; |
549 |
u32 cipher_nid, mac_nid, auth_nid; |
550 |
|
551 |
void setup (ptype type, int dst); |
552 |
bool chk_config (const conf_node *conf, const sockinfo &rsi) const; |
553 |
|
554 |
static u8 get_features () |
555 |
{ |
556 |
u8 f = 0; |
557 |
#if ENABLE_COMPRESSION |
558 |
f |= FEATURE_COMPRESSION; |
559 |
#endif |
560 |
#if ENABLE_ROHC |
561 |
f |= FEATURE_ROHC; |
562 |
#endif |
563 |
#if ENABLE_BRIDGING |
564 |
f |= FEATURE_BRIDGING; |
565 |
#endif |
566 |
return f; |
567 |
} |
568 |
}; |
569 |
|
570 |
void |
571 |
config_packet::setup (ptype type, int dst) |
572 |
{ |
573 |
prot_major = PROTOCOL_MAJOR; |
574 |
prot_minor = PROTOCOL_MINOR; |
575 |
flags = 0; |
576 |
features = get_features (); |
577 |
|
578 |
strncpy ((char *)serial, conf.serial, sizeof (serial)); |
579 |
|
580 |
cipher_nid = htonl (EVP_CIPHER_nid (CIPHER ())); |
581 |
mac_nid = htonl (EVP_MD_type (MAC_DIGEST ())); |
582 |
auth_nid = htonl (EVP_MD_type (AUTH_DIGEST ())); |
583 |
|
584 |
len = sizeof (*this) - sizeof (net_packet); |
585 |
set_hdr (type, dst); |
586 |
} |
587 |
|
588 |
bool |
589 |
config_packet::chk_config (const conf_node *conf, const sockinfo &rsi) const |
590 |
{ |
591 |
if (prot_major != PROTOCOL_MAJOR) |
592 |
slog (L_WARN, _("%s(%s): major version mismatch (remote %d <=> local %d)"), |
593 |
conf->nodename, (const char *)rsi, prot_major, PROTOCOL_MAJOR); |
594 |
else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER ()))) |
595 |
slog (L_WARN, _("%s(%s): cipher algo mismatch (remote %x <=> local %x)"), |
596 |
conf->nodename, (const char *)rsi, ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER ())); |
597 |
else if (mac_nid != htonl (EVP_MD_type (MAC_DIGEST ()))) |
598 |
slog (L_WARN, _("%s(%s): mac algo mismatch (remote %x <=> local %x)"), |
599 |
conf->nodename, (const char *)rsi, ntohl (mac_nid), EVP_MD_type (MAC_DIGEST ())); |
600 |
else if (auth_nid != htonl (EVP_MD_type (AUTH_DIGEST ()))) |
601 |
slog (L_WARN, _("%s(%s): auth algo mismatch (remote %x <=> local %x)"), |
602 |
conf->nodename, (const char *)rsi, ntohl (auth_nid), EVP_MD_type (AUTH_DIGEST ())); |
603 |
else |
604 |
{ |
605 |
int cmp = memcmp (serial, ::conf.serial, sizeof (serial)); |
606 |
|
607 |
if (cmp > 0) |
608 |
slog (L_WARN, _("%s(%s): remote serial newer than local serial - outdated config?"), |
609 |
conf->nodename, (const char *)rsi); |
610 |
else if (cmp == 0) |
611 |
return true; |
612 |
} |
613 |
|
614 |
return false; |
615 |
} |
616 |
|
617 |
struct auth_req_packet : config_packet // UNPROTECTED |
618 |
{ |
619 |
char magic[8]; |
620 |
u8 initiate; // false if this is just an automatic reply |
621 |
u8 protocols; // supported protocols (will be patched on forward) |
622 |
u8 pad2, pad3; |
623 |
auth_encr encr; |
624 |
|
625 |
auth_req_packet (int dst, bool initiate_, u8 protocols_) |
626 |
{ |
627 |
config_packet::setup (PT_AUTH_REQ, dst); |
628 |
memcpy (magic, MAGIC, 8); |
629 |
initiate = !!initiate_; |
630 |
protocols = protocols_; |
631 |
|
632 |
len = sizeof (*this) - sizeof (net_packet); |
633 |
} |
634 |
}; |
635 |
|
636 |
struct auth_res_packet : vpn_packet // UNPROTECTED |
637 |
{ |
638 |
auth_response response; |
639 |
|
640 |
auth_res_packet (int dst) |
641 |
{ |
642 |
set_hdr (PT_AUTH_RES, dst); |
643 |
|
644 |
len = sizeof (*this) - sizeof (net_packet); |
645 |
} |
646 |
}; |
647 |
|
648 |
struct connect_req_packet : vpn_packet |
649 |
{ |
650 |
u8 id, protocols; |
651 |
u8 pad1, pad2; |
652 |
|
653 |
connect_req_packet (int dst, int id_, u8 protocols_) |
654 |
: id(id_) |
655 |
, protocols(protocols_) |
656 |
{ |
657 |
set_hdr (PT_CONNECT_REQ, dst); |
658 |
len = sizeof (*this) - sizeof (net_packet); |
659 |
} |
660 |
}; |
661 |
|
662 |
struct connect_info_packet : vpn_packet |
663 |
{ |
664 |
u8 id, protocols; |
665 |
u8 pad1, pad2; |
666 |
sockinfo si; |
667 |
|
668 |
connect_info_packet (int dst, int id_, const sockinfo &si_, u8 protocols_) |
669 |
: id(id_) |
670 |
, protocols(protocols_) |
671 |
, si(si_) |
672 |
{ |
673 |
set_hdr (PT_CONNECT_INFO, dst); |
674 |
|
675 |
len = sizeof (*this) - sizeof (net_packet); |
676 |
} |
677 |
}; |
678 |
|
679 |
///////////////////////////////////////////////////////////////////////////// |
680 |
|
681 |
void |
682 |
connection::connection_established (const sockinfo &rsi) |
683 |
{ |
684 |
if (!have_snd_auth || !have_rcv_auth) |
685 |
return; |
686 |
|
687 |
si = rsi; |
688 |
protocol = rsi.prot; |
689 |
|
690 |
slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), |
691 |
conf->nodename, (const char *)rsi, |
692 |
vpn->can_direct (THISNODE, conf) ? "direct" : "forwarded", |
693 |
PROTOCOL_MAJOR, prot_minor); |
694 |
|
695 |
if (::conf.script_node_up) |
696 |
{ |
697 |
run_script_cb *cb = new run_script_cb; |
698 |
cb->set<connection, &connection::script_node_up> (this); |
699 |
run_script_queued (cb, _("node-up command execution failed, continuing.")); |
700 |
} |
701 |
|
702 |
delete ictx; ictx = new crypto_ctx (rcv_auth, snd_auth, rcv_ecdh_a, rcv_auth.ecdh, 0); |
703 |
iseqno.reset (ntohl (rcv_auth.rsa.seqno) & 0x7fffffff); |
704 |
|
705 |
delete octx; octx = new crypto_ctx (snd_auth, rcv_auth, snd_ecdh_a, snd_ecdh_b , 1); |
706 |
oseqno = ntohl (snd_auth.rsa.seqno) & 0x7fffffff; |
707 |
|
708 |
// make sure rekeying timeouts are slightly asymmetric |
709 |
ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); |
710 |
rekey.start (rekey_interval, rekey_interval); |
711 |
|
712 |
hmac_error = 0.; |
713 |
|
714 |
keepalive.start (::conf.keepalive); |
715 |
|
716 |
// send queued packets |
717 |
while (tap_packet *p = (tap_packet *)data_queue.get ()) |
718 |
{ |
719 |
if (p->len) send_data_packet (p); |
720 |
delete p; |
721 |
} |
722 |
|
723 |
while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
724 |
{ |
725 |
if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); |
726 |
delete p; |
727 |
} |
728 |
|
729 |
vpn->connection_established (this); |
730 |
} |
731 |
|
732 |
void |
733 |
connection::reset_si () |
734 |
{ |
735 |
if (vpn->can_direct (THISNODE, conf)) |
736 |
protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ()); |
737 |
else |
738 |
{ |
739 |
slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename); |
740 |
protocol = 0; |
741 |
} |
742 |
|
743 |
si.set (conf, protocol); |
744 |
} |
745 |
|
746 |
// ensure sockinfo is valid, forward if necessary |
747 |
const sockinfo & |
748 |
connection::forward_si (const sockinfo &si) const |
749 |
{ |
750 |
if (!si.valid ()) |
751 |
{ |
752 |
connection *r = vpn->find_router_for (this); |
753 |
|
754 |
if (r) |
755 |
{ |
756 |
slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."), |
757 |
conf->nodename, r->conf->nodename); |
758 |
return r->si; |
759 |
} |
760 |
else |
761 |
slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."), |
762 |
conf->nodename); |
763 |
} |
764 |
|
765 |
return si; |
766 |
} |
767 |
|
768 |
void |
769 |
connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
770 |
{ |
771 |
if (!vpn->send_vpn_packet (pkt, si, tos)) |
772 |
reset_connection ("packet send error"); |
773 |
} |
774 |
|
775 |
void |
776 |
connection::send_ping (const sockinfo &si, u8 pong) |
777 |
{ |
778 |
ping_packet *pkt = new ping_packet; |
779 |
|
780 |
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
781 |
|
782 |
slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); |
783 |
send_vpn_packet (pkt, si, IPTOS_LOWDELAY); |
784 |
|
785 |
delete pkt; |
786 |
} |
787 |
|
788 |
void |
789 |
connection::send_reset (const sockinfo &si) |
790 |
{ |
791 |
if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED) |
792 |
{ |
793 |
config_packet *pkt = new config_packet; |
794 |
|
795 |
pkt->setup (vpn_packet::PT_RESET, conf->id); |
796 |
send_vpn_packet (pkt, si, IPTOS_MINCOST); |
797 |
|
798 |
delete pkt; |
799 |
} |
800 |
} |
801 |
|
802 |
void |
803 |
connection::send_auth_request (const sockinfo &si, bool initiate) |
804 |
{ |
805 |
auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); |
806 |
|
807 |
generate_auth_data (); |
808 |
auth_encrypt (conf->rsa_key, snd_auth, pkt->encr); |
809 |
|
810 |
slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); |
811 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly |
812 |
|
813 |
delete pkt; |
814 |
} |
815 |
|
816 |
void |
817 |
connection::send_auth_response (const sockinfo &si) |
818 |
{ |
819 |
auth_res_packet *pkt = new auth_res_packet (conf->id); |
820 |
|
821 |
memcpy (pkt->response.ecdh, rcv_ecdh_b, sizeof rcv_ecdh_b); |
822 |
auth_hash (rcv_auth, rcv_ecdh_b, pkt->response.mac); |
823 |
|
824 |
slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); |
825 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
826 |
|
827 |
delete pkt; |
828 |
} |
829 |
|
830 |
void |
831 |
connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) |
832 |
{ |
833 |
slog (L_TRACE, "%s << PT_CONNECT_INFO(%s,%s,p%02x)", conf->nodename, |
834 |
vpn->conns[rid - 1]->conf->nodename, (const char *)rsi, |
835 |
conf->protocols); |
836 |
|
837 |
connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); |
838 |
|
839 |
r->hmac_set (octx); |
840 |
send_vpn_packet (r, si); |
841 |
|
842 |
delete r; |
843 |
} |
844 |
|
845 |
inline void |
846 |
connection::establish_connection_cb (ev::timer &w, int revents) |
847 |
{ |
848 |
if (!(ictx && octx) |
849 |
&& conf != THISNODE |
850 |
&& connectmode != conf_node::C_NEVER |
851 |
&& connectmode != conf_node::C_DISABLED |
852 |
&& !w.is_active ()) |
853 |
{ |
854 |
// a bit hacky, if ondemand, and packets are no longer queued, then reset the connection |
855 |
// and stop trying. should probably be handled by a per-connection expire handler. |
856 |
if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ()) |
857 |
{ |
858 |
reset_connection ("no demand"); |
859 |
return; |
860 |
} |
861 |
|
862 |
last_establish_attempt = ev_now (); |
863 |
|
864 |
ev::tstamp retry_int = ev::tstamp (retry_cnt & 3 |
865 |
? (retry_cnt & 3) + 1 |
866 |
: 1 << (retry_cnt >> 2)); |
867 |
|
868 |
reset_si (); |
869 |
|
870 |
bool slow = (si.prot & PROT_SLOW) || (conf->low_power || THISNODE->low_power); |
871 |
|
872 |
if (si.prot && !si.host && vpn->can_direct (THISNODE, conf)) |
873 |
{ |
874 |
/*TODO*/ /* start the timer so we don't recurse endlessly */ |
875 |
w.start (1); |
876 |
vpn->send_connect_request (this); |
877 |
} |
878 |
else |
879 |
{ |
880 |
if (si.valid ()) |
881 |
slog (L_DEBUG, _("%s: sending direct connection request to %s."), |
882 |
conf->nodename, (const char *)si); |
883 |
|
884 |
const sockinfo &dsi = forward_si (si); |
885 |
|
886 |
slow = slow || (dsi.prot & PROT_SLOW); |
887 |
|
888 |
if (dsi.valid () && auth_rate_limiter.can (dsi)) |
889 |
{ |
890 |
// use ping after the first few retries |
891 |
// TODO: on rekeys, the other node might not interpret ping correctly, |
892 |
// TODO: as it will still have a valid connection |
893 |
if (retry_cnt < 4 && (!conf->low_power || THISNODE->low_power)) |
894 |
send_auth_request (dsi, true); |
895 |
else |
896 |
send_ping (dsi, 0); |
897 |
} |
898 |
} |
899 |
|
900 |
retry_int *= slow ? 4. : 0.9; |
901 |
|
902 |
if (retry_int < conf->max_retry) |
903 |
retry_cnt++; |
904 |
else |
905 |
retry_int = conf->max_retry; |
906 |
|
907 |
w.start (retry_int); |
908 |
} |
909 |
} |
910 |
|
911 |
void |
912 |
connection::reset_connection (const char *reason) |
913 |
{ |
914 |
if (ictx && octx) |
915 |
{ |
916 |
slog (L_INFO, _("%s(%s): connection lost (%s)"), |
917 |
conf->nodename, (const char *)si, reason); |
918 |
|
919 |
if (::conf.script_node_down) |
920 |
{ |
921 |
run_script_cb *cb = new run_script_cb; |
922 |
cb->set<connection, &connection::script_node_down> (this); |
923 |
run_script_queued (cb, _("node-down command execution failed, continuing.")); |
924 |
} |
925 |
} |
926 |
|
927 |
delete ictx; ictx = 0; |
928 |
delete octx; octx = 0; |
929 |
|
930 |
si.host = 0; |
931 |
|
932 |
have_snd_auth = false; |
933 |
have_rcv_auth = false; |
934 |
auth_expire = 0.; |
935 |
|
936 |
last_activity = 0.; |
937 |
//last_si_change = 0.; |
938 |
retry_cnt = 0; |
939 |
|
940 |
rekey.stop (); |
941 |
keepalive.stop (); |
942 |
establish_connection.stop (); |
943 |
} |
944 |
|
945 |
void |
946 |
connection::shutdown () |
947 |
{ |
948 |
if (ictx && octx) |
949 |
send_reset (si); |
950 |
|
951 |
reset_connection ("shutdown"); |
952 |
} |
953 |
|
954 |
// poor-man's rekeying |
955 |
inline void |
956 |
connection::rekey_cb (ev::timer &w, int revents) |
957 |
{ |
958 |
reset_connection ("rekeying"); |
959 |
establish_connection (); |
960 |
} |
961 |
|
962 |
void |
963 |
connection::send_data_packet (tap_packet *pkt) |
964 |
{ |
965 |
vpndata_packet *p = new vpndata_packet; |
966 |
int tos = 0; |
967 |
|
968 |
// I am not hilarious about peeking into packets, but so be it. |
969 |
if (conf->inherit_tos && pkt->is_ipv4 ()) |
970 |
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
971 |
|
972 |
p->setup (this, conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
973 |
send_vpn_packet (p, si, tos); |
974 |
|
975 |
delete p; |
976 |
|
977 |
if (oseqno > MAX_SEQNO) |
978 |
rekey (); |
979 |
} |
980 |
|
981 |
void |
982 |
connection::post_inject_queue () |
983 |
{ |
984 |
// force a connection every now and when when packets are sent (max 1/s) |
985 |
if (ev_now () - last_establish_attempt >= (conf->low_power || THISNODE->low_power ? 2.95 : 0.95)) // arbitrary |
986 |
establish_connection.stop (); |
987 |
|
988 |
establish_connection (); |
989 |
} |
990 |
|
991 |
void |
992 |
connection::inject_data_packet (tap_packet *pkt) |
993 |
{ |
994 |
if (ictx && octx) |
995 |
send_data_packet (pkt); |
996 |
else |
997 |
{ |
998 |
data_queue.put (new tap_packet (*pkt)); |
999 |
post_inject_queue (); |
1000 |
} |
1001 |
} |
1002 |
|
1003 |
void |
1004 |
connection::inject_vpn_packet (vpn_packet *pkt, int tos) |
1005 |
{ |
1006 |
if (ictx && octx) |
1007 |
send_vpn_packet (pkt, si, tos); |
1008 |
else |
1009 |
{ |
1010 |
vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); |
1011 |
post_inject_queue (); |
1012 |
} |
1013 |
} |
1014 |
|
1015 |
void |
1016 |
connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
1017 |
{ |
1018 |
last_activity = ev_now (); |
1019 |
|
1020 |
slog (L_NOISE, "%s >> received packet type %d from %d to %d.", |
1021 |
conf->nodename, pkt->typ (), pkt->src (), pkt->dst ()); |
1022 |
|
1023 |
if (connectmode == conf_node::C_DISABLED) |
1024 |
return; |
1025 |
|
1026 |
switch (pkt->typ ()) |
1027 |
{ |
1028 |
case vpn_packet::PT_PING: |
1029 |
slog (L_TRACE, "%s >> PT_PING", conf->nodename); |
1030 |
|
1031 |
// we send pings instead of auth packets after some retries, |
1032 |
// so reset the retry counter and establish a connection |
1033 |
// when we receive a ping. |
1034 |
if (!ictx) |
1035 |
{ |
1036 |
if (auth_rate_limiter.can (rsi)) |
1037 |
send_auth_request (rsi, true); |
1038 |
} |
1039 |
else |
1040 |
// we would love to change the socket address here, but ping's aren't |
1041 |
// authenticated, so we best ignore it. |
1042 |
send_ping (rsi, 1); // pong |
1043 |
|
1044 |
break; |
1045 |
|
1046 |
case vpn_packet::PT_PONG: |
1047 |
slog (L_TRACE, "%s >> PT_PONG", conf->nodename); |
1048 |
|
1049 |
// a PONG might mean that the other side doesn't really know |
1050 |
// about our desire for communication. |
1051 |
establish_connection (); |
1052 |
break; |
1053 |
|
1054 |
case vpn_packet::PT_RESET: |
1055 |
slog (L_TRACE, "%s >> PT_RESET", conf->nodename); |
1056 |
|
1057 |
if (ictx && octx) |
1058 |
{ |
1059 |
reset_connection ("remote reset"); |
1060 |
|
1061 |
config_packet *p = (config_packet *) pkt; |
1062 |
|
1063 |
if (p->chk_config (conf, rsi) && connectmode == conf_node::C_ALWAYS) |
1064 |
establish_connection (); |
1065 |
} |
1066 |
|
1067 |
break; |
1068 |
|
1069 |
case vpn_packet::PT_AUTH_REQ: |
1070 |
if (auth_rate_limiter.can (rsi)) |
1071 |
{ |
1072 |
auth_req_packet *p = (auth_req_packet *)pkt; |
1073 |
|
1074 |
slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)", |
1075 |
conf->nodename, p->initiate ? "initiate" : "reply", |
1076 |
p->protocols, p->features); |
1077 |
|
1078 |
if (memcmp (p->magic, MAGIC, 8)) |
1079 |
{ |
1080 |
slog (L_WARN, _("%s(%s): protocol magic mismatch - stray packet?"), |
1081 |
conf->nodename, (const char *)rsi); |
1082 |
} |
1083 |
else if (p->chk_config (conf, rsi)) |
1084 |
{ |
1085 |
if (p->prot_minor != PROTOCOL_MINOR) |
1086 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1087 |
conf->nodename, (const char *)rsi, |
1088 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1089 |
|
1090 |
if (p->initiate) |
1091 |
{ |
1092 |
send_auth_request (rsi, false); |
1093 |
|
1094 |
if (ictx && octx) |
1095 |
reset_connection ("reconnect"); |
1096 |
} |
1097 |
|
1098 |
auth_data auth; |
1099 |
|
1100 |
if (!auth_decrypt (::conf.rsa_key, p->encr, auth)) |
1101 |
{ |
1102 |
slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
1103 |
conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
1104 |
} |
1105 |
else |
1106 |
{ |
1107 |
bool chg = !have_rcv_auth || !slow_memeq (&rcv_auth, &auth, sizeof auth); |
1108 |
|
1109 |
rcv_auth = auth; |
1110 |
have_rcv_auth = true; |
1111 |
|
1112 |
send_auth_response (rsi); |
1113 |
|
1114 |
if (chg) |
1115 |
{ |
1116 |
conf->protocols = p->protocols; |
1117 |
features = p->features & config_packet::get_features (); |
1118 |
|
1119 |
connection_established (rsi); |
1120 |
} |
1121 |
} |
1122 |
|
1123 |
break; |
1124 |
} |
1125 |
|
1126 |
send_reset (rsi); |
1127 |
} |
1128 |
|
1129 |
break; |
1130 |
|
1131 |
case vpn_packet::PT_AUTH_RES: |
1132 |
{ |
1133 |
auth_res_packet *p = (auth_res_packet *)pkt; |
1134 |
|
1135 |
slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); |
1136 |
|
1137 |
auth_mac local_mac; |
1138 |
auth_hash (snd_auth, p->response.ecdh, local_mac); |
1139 |
|
1140 |
if (!slow_memeq (&p->response.mac, local_mac, sizeof local_mac)) |
1141 |
{ |
1142 |
slog (L_ERR, _("%s(%s): unrequested or outdated auth response, ignoring."), |
1143 |
conf->nodename, (const char *)rsi); |
1144 |
} |
1145 |
else if (!have_snd_auth) |
1146 |
{ |
1147 |
memcpy (snd_ecdh_b, p->response.ecdh, sizeof snd_ecdh_b); |
1148 |
|
1149 |
have_snd_auth = true; |
1150 |
connection_established (rsi); |
1151 |
} |
1152 |
} |
1153 |
break; |
1154 |
|
1155 |
case vpn_packet::PT_DATA_COMPRESSED: |
1156 |
#if !ENABLE_COMPRESSION |
1157 |
send_reset (rsi); |
1158 |
break; |
1159 |
#endif |
1160 |
|
1161 |
case vpn_packet::PT_DATA_UNCOMPRESSED: |
1162 |
|
1163 |
if (ictx && octx) |
1164 |
{ |
1165 |
vpndata_packet *p = (vpndata_packet *)pkt; |
1166 |
|
1167 |
if (!p->hmac_chk (ictx)) |
1168 |
{ |
1169 |
// rekeying often creates temporary hmac auth floods |
1170 |
// we assume they don't take longer than a few seconds normally, |
1171 |
// and suppress messages and resets during that time. |
1172 |
//TODO: should be done per source address |
1173 |
if (!hmac_error) |
1174 |
{ |
1175 |
hmac_error = ev_now () + 3; |
1176 |
break; |
1177 |
} |
1178 |
else if (hmac_error >= ev_now ()) |
1179 |
break; // silently suppress |
1180 |
else |
1181 |
{ |
1182 |
slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" |
1183 |
"could be an attack, or just corruption or a synchronization error."), |
1184 |
conf->nodename, (const char *)rsi); |
1185 |
// reset |
1186 |
} |
1187 |
} |
1188 |
else |
1189 |
{ |
1190 |
u32 seqno; |
1191 |
tap_packet *d = p->unpack (this, seqno); |
1192 |
int seqclass = iseqno.seqno_classify (seqno); |
1193 |
|
1194 |
hmac_error = 0; |
1195 |
|
1196 |
if (seqclass == 0) // ok |
1197 |
{ |
1198 |
vpn->tap->send (d); |
1199 |
|
1200 |
if (si != rsi) |
1201 |
{ |
1202 |
// fast re-sync on source address changes, useful especially for tcp/ip |
1203 |
//if (last_si_change < ev_now () + 5.) |
1204 |
// { |
1205 |
slog (L_INFO, _("%s(%s): changing socket address to %s."), |
1206 |
conf->nodename, (const char *)si, (const char *)rsi); |
1207 |
|
1208 |
si = rsi; |
1209 |
|
1210 |
if (::conf.script_node_change) |
1211 |
{ |
1212 |
run_script_cb *cb = new run_script_cb; |
1213 |
cb->set<connection, &connection::script_node_change> (this); |
1214 |
run_script_queued (cb, _("node-change command execution failed, continuing.")); |
1215 |
} |
1216 |
|
1217 |
// } |
1218 |
//else |
1219 |
// slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."), |
1220 |
// conf->nodename, (const char *)si, (const char *)rsi); |
1221 |
} |
1222 |
} |
1223 |
else if (seqclass == 1) // far history |
1224 |
slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). " |
1225 |
"possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1); |
1226 |
else if (seqclass == 2) // in-window duplicate, happens often on wireless |
1227 |
slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). " |
1228 |
"possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1); |
1229 |
else if (seqclass == 3) // reset |
1230 |
{ |
1231 |
slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). " |
1232 |
"probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1); |
1233 |
send_reset (rsi); |
1234 |
} |
1235 |
|
1236 |
delete d; |
1237 |
break; |
1238 |
} |
1239 |
} |
1240 |
|
1241 |
send_reset (rsi); |
1242 |
break; |
1243 |
|
1244 |
case vpn_packet::PT_CONNECT_REQ: |
1245 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1246 |
{ |
1247 |
connect_req_packet *p = (connect_req_packet *)pkt; |
1248 |
|
1249 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1250 |
{ |
1251 |
connection *c = vpn->conns[p->id - 1]; |
1252 |
conf->protocols = p->protocols; |
1253 |
|
1254 |
slog (L_TRACE, "%s >> PT_CONNECT_REQ(%s,p%02x) [%d]", |
1255 |
conf->nodename, vpn->conns[p->id - 1]->conf->nodename, |
1256 |
p->protocols, |
1257 |
c->ictx && c->octx); |
1258 |
|
1259 |
if (c->ictx && c->octx) |
1260 |
{ |
1261 |
// send connect_info packets to both sides, in case one is |
1262 |
// behind a nat firewall (or both ;) |
1263 |
c->send_connect_info (conf->id, si, conf->protocols); |
1264 |
send_connect_info (c->conf->id, c->si, c->conf->protocols); |
1265 |
} |
1266 |
else |
1267 |
c->establish_connection (); |
1268 |
} |
1269 |
else |
1270 |
slog (L_WARN, |
1271 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1272 |
p->id); |
1273 |
} |
1274 |
|
1275 |
break; |
1276 |
|
1277 |
case vpn_packet::PT_CONNECT_INFO: |
1278 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1279 |
{ |
1280 |
connect_info_packet *p = (connect_info_packet *)pkt; |
1281 |
|
1282 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1283 |
{ |
1284 |
connection *c = vpn->conns[p->id - 1]; |
1285 |
|
1286 |
c->conf->protocols = p->protocols; |
1287 |
protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); |
1288 |
p->si.upgrade_protocol (protocol, c->conf); |
1289 |
|
1290 |
slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s,protocols=%02x,protocol=%02x,upgradable=%02x) [%d]", |
1291 |
conf->nodename, |
1292 |
vpn->conns[p->id - 1]->conf->nodename, |
1293 |
(const char *)p->si, |
1294 |
p->protocols, |
1295 |
protocol, |
1296 |
p->si.supported_protocols (c->conf), |
1297 |
!c->ictx && !c->octx); |
1298 |
|
1299 |
const sockinfo &dsi = forward_si (p->si); |
1300 |
|
1301 |
if (dsi.valid ()) |
1302 |
c->send_auth_request (dsi, true); |
1303 |
else |
1304 |
slog (L_INFO, "connect info for %s received (%s), but still unable to contact.", |
1305 |
vpn->conns[p->id - 1]->conf->nodename, |
1306 |
(const char *)p->si); |
1307 |
} |
1308 |
else |
1309 |
slog (L_WARN, |
1310 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1311 |
p->id); |
1312 |
} |
1313 |
|
1314 |
break; |
1315 |
|
1316 |
default: |
1317 |
send_reset (rsi); |
1318 |
break; |
1319 |
} |
1320 |
} |
1321 |
|
1322 |
inline void |
1323 |
connection::keepalive_cb (ev::timer &w, int revents) |
1324 |
{ |
1325 |
ev_tstamp when = last_activity + ::conf.keepalive - ev::now (); |
1326 |
|
1327 |
if (when >= 0) |
1328 |
w.start (when); |
1329 |
else if (when < -15) |
1330 |
{ |
1331 |
reset_connection ("keepalive overdue"); |
1332 |
establish_connection (); |
1333 |
} |
1334 |
else if (conf->connectmode != conf_node::C_ONDEMAND |
1335 |
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
1336 |
{ |
1337 |
w.start (3); |
1338 |
send_ping (si); |
1339 |
} |
1340 |
else if (when >= -10) |
1341 |
// hold ondemand connections implicitly a few seconds longer |
1342 |
// should delete octx, though, or something like that ;) |
1343 |
w.start (when + 10); |
1344 |
else |
1345 |
reset_connection ("keepalive timeout"); |
1346 |
} |
1347 |
|
1348 |
void |
1349 |
connection::send_connect_request (int id) |
1350 |
{ |
1351 |
connect_req_packet *p = new connect_req_packet (conf->id, id, THISNODE->protocols); |
1352 |
|
1353 |
slog (L_TRACE, "%s << PT_CONNECT_REQ(%s,p%02x)", |
1354 |
conf->nodename, vpn->conns[id - 1]->conf->nodename, |
1355 |
THISNODE->protocols); |
1356 |
p->hmac_set (octx); |
1357 |
send_vpn_packet (p, si); |
1358 |
|
1359 |
delete p; |
1360 |
} |
1361 |
|
1362 |
void |
1363 |
connection::script_init_env (const char *ext) |
1364 |
{ |
1365 |
char *env; |
1366 |
asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env); |
1367 |
asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env); |
1368 |
asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext, |
1369 |
0xfe, 0xfd, 0x80, 0x00, conf->id >> 8, |
1370 |
conf->id & 0xff); putenv (env); |
1371 |
} |
1372 |
|
1373 |
void |
1374 |
connection::script_init_connect_env () |
1375 |
{ |
1376 |
vpn->script_init_env (); |
1377 |
|
1378 |
char *env; |
1379 |
asprintf (&env, "DESTID=%d", conf->id); putenv (env); |
1380 |
asprintf (&env, "DESTSI=%s", (const char *)si); putenv (env); |
1381 |
asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); |
1382 |
asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); |
1383 |
asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); |
1384 |
} |
1385 |
|
1386 |
inline const char * |
1387 |
connection::script_node_up () |
1388 |
{ |
1389 |
script_init_connect_env (); |
1390 |
|
1391 |
putenv ((char *)"STATE=up"); |
1392 |
|
1393 |
char *filename; |
1394 |
asprintf (&filename, |
1395 |
"%s/%s", |
1396 |
confbase, |
1397 |
::conf.script_node_up ? ::conf.script_node_up : "node-up"); |
1398 |
|
1399 |
return filename; |
1400 |
} |
1401 |
|
1402 |
inline const char * |
1403 |
connection::script_node_change () |
1404 |
{ |
1405 |
script_init_connect_env (); |
1406 |
|
1407 |
putenv ((char *)"STATE=change"); |
1408 |
|
1409 |
char *filename; |
1410 |
asprintf (&filename, |
1411 |
"%s/%s", |
1412 |
confbase, |
1413 |
::conf.script_node_change ? ::conf.script_node_change : "node-change"); |
1414 |
|
1415 |
return filename; |
1416 |
} |
1417 |
|
1418 |
inline const char * |
1419 |
connection::script_node_down () |
1420 |
{ |
1421 |
script_init_connect_env (); |
1422 |
|
1423 |
putenv ((char *)"STATE=down"); |
1424 |
|
1425 |
char *filename; |
1426 |
asprintf (&filename, |
1427 |
"%s/%s", |
1428 |
confbase, |
1429 |
::conf.script_node_down ? ::conf.script_node_down : "node-down"); |
1430 |
|
1431 |
return filename; |
1432 |
} |
1433 |
|
1434 |
connection::connection (struct vpn *vpn, conf_node *conf) |
1435 |
: vpn(vpn), conf(conf), |
1436 |
#if ENABLE_DNS |
1437 |
dns (0), |
1438 |
#endif |
1439 |
data_queue(conf->max_ttl, conf->max_queue + 1), |
1440 |
vpn_queue(conf->max_ttl, conf->max_queue + 1) |
1441 |
{ |
1442 |
rekey .set<connection, &connection::rekey_cb > (this); |
1443 |
keepalive .set<connection, &connection::keepalive_cb > (this); |
1444 |
establish_connection.set<connection, &connection::establish_connection_cb> (this); |
1445 |
|
1446 |
last_establish_attempt = 0.; |
1447 |
octx = ictx = 0; |
1448 |
|
1449 |
connectmode = conf->connectmode; |
1450 |
|
1451 |
// queue a dummy packet to force an initial connection attempt |
1452 |
if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED) |
1453 |
vpn_queue.put (new net_packet); |
1454 |
|
1455 |
reset_connection ("startup"); |
1456 |
} |
1457 |
|
1458 |
connection::~connection () |
1459 |
{ |
1460 |
shutdown (); |
1461 |
} |
1462 |
|
1463 |
void |
1464 |
connection_init () |
1465 |
{ |
1466 |
auth_rate_limiter.clear (); |
1467 |
reset_rate_limiter.clear (); |
1468 |
} |
1469 |
|