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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 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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// openssl 0.9.8 compatibility |
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#if OPENSSL_VERSION_NUMBER < 0x10100000 |
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#define require101(exp) exp |
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#else |
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#define require101(exp) equire (exp) |
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#endif |
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|
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#include "conf.h" |
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#include "slog.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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#define MAGIC "HUHN\xbd\xc6\xdb\x82" // 8 bytes of magic//D |
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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_CTX 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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HMAC_CTX_init (&hctx); |
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require101 (HMAC_Init_ex (&hctx, mac_key, MAC_KEYSIZE, MAC_DIGEST (), 0)); |
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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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HMAC_CTX_cleanup (&hctx); |
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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 |
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} |
198 |
|
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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); |
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} |
211 |
|
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// every use prolongs the expiry |
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auth_expire = ev_now () + AUTH_TTL; |
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} |
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|
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////////////////////////////////////////////////////////////////////////////// |
217 |
|
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pkt_queue::pkt_queue (double max_ttl, int max_queue) |
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: max_ttl (max_ttl), max_queue (max_queue) |
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{ |
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queue = new pkt [max_queue]; |
222 |
|
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i = 0; |
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j = 0; |
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|
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expire.set<pkt_queue, &pkt_queue::expire_cb> (this); |
227 |
} |
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|
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pkt_queue::~pkt_queue () |
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{ |
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while (net_packet *p = get ()) |
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delete p; |
233 |
|
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delete [] queue; |
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} |
236 |
|
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void |
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pkt_queue::expire_cb (ev::timer &w, int revents) |
239 |
{ |
240 |
ev_tstamp expire = ev_now () - max_ttl; |
241 |
|
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for (;;) |
243 |
{ |
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if (empty ()) |
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break; |
246 |
|
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double diff = queue[j].tstamp - expire; |
248 |
|
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if (diff >= 0.) |
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{ |
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w.start (diff > 0.5 ? diff : 0.5); |
252 |
break; |
253 |
} |
254 |
|
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delete get (); |
256 |
} |
257 |
} |
258 |
|
259 |
void |
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pkt_queue::put (net_packet *p) |
261 |
{ |
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ev_tstamp now = ev_now (); |
263 |
|
264 |
// start expiry timer |
265 |
if (empty ()) |
266 |
expire.start (max_ttl); |
267 |
|
268 |
int ni = i + 1 == max_queue ? 0 : i + 1; |
269 |
|
270 |
if (ni == j) |
271 |
delete get (); |
272 |
|
273 |
queue[i].pkt = p; |
274 |
queue[i].tstamp = now; |
275 |
|
276 |
i = ni; |
277 |
} |
278 |
|
279 |
net_packet * |
280 |
pkt_queue::get () |
281 |
{ |
282 |
if (empty ()) |
283 |
return 0; |
284 |
|
285 |
net_packet *p = queue[j].pkt; |
286 |
queue[j].pkt = 0; |
287 |
|
288 |
j = j + 1 == max_queue ? 0 : j + 1; |
289 |
|
290 |
return p; |
291 |
} |
292 |
|
293 |
struct net_rateinfo |
294 |
{ |
295 |
u32 host; |
296 |
double pcnt, diff; |
297 |
tstamp last; |
298 |
}; |
299 |
|
300 |
// only do action once every x seconds per host whole allowing bursts. |
301 |
// this implementation ("splay list" ;) is inefficient, |
302 |
// but low on resources. |
303 |
struct net_rate_limiter : list<net_rateinfo> |
304 |
{ |
305 |
# define NRL_ALPHA (1. - 1. / 600.) // allow bursts |
306 |
# define NRL_CUTOFF 10. // one event every CUTOFF seconds |
307 |
# define NRL_EXPIRE (NRL_CUTOFF * 30.) // expire entries after this time |
308 |
# define NRL_MAXDIF (NRL_CUTOFF * (1. / (1. - NRL_ALPHA))) // maximum diff /count value |
309 |
|
310 |
bool can (const sockinfo &si) { return can((u32)si.host); } |
311 |
bool can (u32 host); |
312 |
}; |
313 |
|
314 |
static net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
315 |
|
316 |
bool |
317 |
net_rate_limiter::can (u32 host) |
318 |
{ |
319 |
iterator i; |
320 |
|
321 |
for (i = begin (); i != end (); ) |
322 |
if (i->host == host) |
323 |
break; |
324 |
else if (i->last < ev_now () - NRL_EXPIRE) |
325 |
i = erase (i); |
326 |
else |
327 |
i++; |
328 |
|
329 |
if (i == end ()) |
330 |
{ |
331 |
net_rateinfo ri; |
332 |
|
333 |
ri.host = host; |
334 |
ri.pcnt = 1.; |
335 |
ri.diff = NRL_MAXDIF; |
336 |
ri.last = ev_now (); |
337 |
|
338 |
push_front (ri); |
339 |
|
340 |
return true; |
341 |
} |
342 |
else |
343 |
{ |
344 |
net_rateinfo ri (*i); |
345 |
erase (i); |
346 |
|
347 |
ri.pcnt = ri.pcnt * NRL_ALPHA; |
348 |
ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last); |
349 |
|
350 |
ri.last = ev_now (); |
351 |
|
352 |
double dif = ri.diff / ri.pcnt; |
353 |
|
354 |
bool send = dif > NRL_CUTOFF; |
355 |
|
356 |
if (dif > NRL_MAXDIF) |
357 |
{ |
358 |
ri.pcnt = 1.; |
359 |
ri.diff = NRL_MAXDIF; |
360 |
} |
361 |
else if (send) |
362 |
ri.pcnt++; |
363 |
|
364 |
push_front (ri); |
365 |
|
366 |
return send; |
367 |
} |
368 |
} |
369 |
|
370 |
///////////////////////////////////////////////////////////////////////////// |
371 |
|
372 |
void |
373 |
hmac_packet::hmac_gen (crypto_ctx *ctx, u8 *hmac_digest) |
374 |
{ |
375 |
HMAC_CTX *hctx = &ctx->hctx; |
376 |
|
377 |
require101 (HMAC_Init_ex (hctx, 0, 0, 0, 0)); |
378 |
require101 (HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), len - sizeof (hmac_packet))); |
379 |
require101 (HMAC_Final (hctx, hmac_digest, 0)); |
380 |
} |
381 |
|
382 |
void |
383 |
hmac_packet::hmac_set (crypto_ctx *ctx) |
384 |
{ |
385 |
unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
386 |
hmac_gen (ctx, hmac_digest); |
387 |
memcpy (hmac, hmac_digest, HMACLENGTH); |
388 |
} |
389 |
|
390 |
bool |
391 |
hmac_packet::hmac_chk (crypto_ctx *ctx) |
392 |
{ |
393 |
unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
394 |
hmac_gen (ctx, hmac_digest); |
395 |
return !memcmp (hmac, hmac_digest, HMACLENGTH); |
396 |
} |
397 |
|
398 |
void |
399 |
vpn_packet::set_hdr (ptype type_, unsigned int dst) |
400 |
{ |
401 |
type = type_; |
402 |
|
403 |
int src = THISNODE->id; |
404 |
|
405 |
src1 = src; |
406 |
srcdst = ((src >> 8) << 4) | (dst >> 8); |
407 |
dst1 = dst; |
408 |
} |
409 |
|
410 |
#define MAXVPNDATA (MAX_MTU - 6 - 6) |
411 |
#define DATAHDR (sizeof (u32) + RAND_SIZE) |
412 |
|
413 |
struct vpndata_packet : vpn_packet |
414 |
{ |
415 |
u8 data[MAXVPNDATA + DATAHDR]; // seqno |
416 |
|
417 |
void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno); |
418 |
tap_packet *unpack (connection *conn, u32 &seqno); |
419 |
|
420 |
private: |
421 |
const u32 data_hdr_size () const |
422 |
{ |
423 |
return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; |
424 |
} |
425 |
}; |
426 |
|
427 |
void |
428 |
vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
429 |
{ |
430 |
EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
431 |
int outl = 0, outl2; |
432 |
ptype type = PT_DATA_UNCOMPRESSED; |
433 |
|
434 |
#if ENABLE_COMPRESSION |
435 |
u8 cdata[MAX_MTU]; |
436 |
|
437 |
if (conn->features & FEATURE_COMPRESSION) |
438 |
{ |
439 |
u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
440 |
|
441 |
if (cl) |
442 |
{ |
443 |
type = PT_DATA_COMPRESSED; |
444 |
d = cdata; |
445 |
l = cl + 2; |
446 |
|
447 |
d[0] = cl >> 8; |
448 |
d[1] = cl; |
449 |
} |
450 |
} |
451 |
#endif |
452 |
|
453 |
require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 1)); |
454 |
|
455 |
struct { |
456 |
#if RAND_SIZE |
457 |
u8 rnd[RAND_SIZE]; |
458 |
#endif |
459 |
u32 seqno; |
460 |
} datahdr; |
461 |
|
462 |
datahdr.seqno = ntohl (seqno); |
463 |
#if RAND_SIZE |
464 |
// NB: a constant (per session) random prefix |
465 |
// is likely enough, but we don't take any chances. |
466 |
conn->oiv.get (datahdr.rnd, RAND_SIZE); |
467 |
#endif |
468 |
|
469 |
require (EVP_EncryptUpdate (cctx, |
470 |
(unsigned char *) data + outl, &outl2, |
471 |
(unsigned char *) &datahdr, DATAHDR)); |
472 |
outl += outl2; |
473 |
|
474 |
require (EVP_EncryptUpdate (cctx, |
475 |
(unsigned char *) data + outl, &outl2, |
476 |
(unsigned char *) d, l)); |
477 |
outl += outl2; |
478 |
|
479 |
require (EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2)); |
480 |
outl += outl2; |
481 |
|
482 |
len = outl + data_hdr_size (); |
483 |
|
484 |
set_hdr (type, dst); |
485 |
|
486 |
hmac_set (conn->octx); |
487 |
} |
488 |
|
489 |
tap_packet * |
490 |
vpndata_packet::unpack (connection *conn, u32 &seqno) |
491 |
{ |
492 |
EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; |
493 |
int outl = 0, outl2; |
494 |
tap_packet *p = new tap_packet; |
495 |
u8 *d; |
496 |
u32 l = len - data_hdr_size (); |
497 |
|
498 |
require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 0)); |
499 |
|
500 |
#if ENABLE_COMPRESSION |
501 |
u8 cdata[MAX_MTU]; |
502 |
|
503 |
if (type == PT_DATA_COMPRESSED) |
504 |
d = cdata; |
505 |
else |
506 |
#endif |
507 |
d = &(*p)[6 + 6] - DATAHDR; |
508 |
|
509 |
// we play do evil games with the struct layout atm. |
510 |
// pending better solutions, we at least do some verification. |
511 |
// this is fine, as we left ISO territory long ago. |
512 |
require (DATAHDR <= 16); |
513 |
require ((u8 *)(&p->len + 1) == &(*p)[0]); |
514 |
|
515 |
// this can overwrite the len/dst/src fields |
516 |
require (EVP_DecryptUpdate (cctx, |
517 |
d, &outl2, |
518 |
(unsigned char *)&data, len - data_hdr_size ())); |
519 |
outl += outl2; |
520 |
|
521 |
require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2)); |
522 |
outl += outl2; |
523 |
|
524 |
seqno = ntohl (*(u32 *)(d + RAND_SIZE)); |
525 |
|
526 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
527 |
id2mac (src (), p->src); |
528 |
|
529 |
#if ENABLE_COMPRESSION |
530 |
if (type == PT_DATA_COMPRESSED) |
531 |
{ |
532 |
u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; |
533 |
|
534 |
p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0, |
535 |
&(*p)[6 + 6], MAX_MTU) |
536 |
+ 6 + 6; |
537 |
} |
538 |
else |
539 |
p->len = outl + (6 + 6 - DATAHDR); |
540 |
#endif |
541 |
|
542 |
return p; |
543 |
} |
544 |
|
545 |
struct ping_packet : vpn_packet |
546 |
{ |
547 |
void setup (int dst, ptype type) |
548 |
{ |
549 |
set_hdr (type, dst); |
550 |
len = sizeof (*this) - sizeof (net_packet); |
551 |
} |
552 |
}; |
553 |
|
554 |
struct config_packet : vpn_packet |
555 |
{ |
556 |
u8 serial[SERIAL_SIZE]; |
557 |
u8 prot_major, prot_minor, randsize; |
558 |
u8 flags, features, pad6, pad7, pad8; |
559 |
u32 cipher_nid, mac_nid, auth_nid; |
560 |
|
561 |
void setup (ptype type, int dst); |
562 |
bool chk_config (const conf_node *conf, const sockinfo &rsi) const; |
563 |
|
564 |
static u8 get_features () |
565 |
{ |
566 |
u8 f = 0; |
567 |
#if ENABLE_COMPRESSION |
568 |
f |= FEATURE_COMPRESSION; |
569 |
#endif |
570 |
#if ENABLE_ROHC |
571 |
f |= FEATURE_ROHC; |
572 |
#endif |
573 |
#if ENABLE_BRIDGING |
574 |
f |= FEATURE_BRIDGING; |
575 |
#endif |
576 |
return f; |
577 |
} |
578 |
}; |
579 |
|
580 |
void |
581 |
config_packet::setup (ptype type, int dst) |
582 |
{ |
583 |
prot_major = PROTOCOL_MAJOR; |
584 |
prot_minor = PROTOCOL_MINOR; |
585 |
randsize = RAND_SIZE; |
586 |
flags = 0; |
587 |
features = get_features (); |
588 |
|
589 |
strncpy ((char *)serial, conf.serial, sizeof (serial)); |
590 |
|
591 |
cipher_nid = htonl (EVP_CIPHER_nid (CIPHER ())); |
592 |
mac_nid = htonl (EVP_MD_type (MAC_DIGEST ())); |
593 |
auth_nid = htonl (EVP_MD_type (AUTH_DIGEST ())); |
594 |
|
595 |
len = sizeof (*this) - sizeof (net_packet); |
596 |
set_hdr (type, dst); |
597 |
} |
598 |
|
599 |
bool |
600 |
config_packet::chk_config (const conf_node *conf, const sockinfo &rsi) const |
601 |
{ |
602 |
if (prot_major != PROTOCOL_MAJOR) |
603 |
slog (L_WARN, _("%s(%s): major version mismatch (remote %d <=> local %d)"), |
604 |
conf->nodename, (const char *)rsi, prot_major, PROTOCOL_MAJOR); |
605 |
else if (randsize != RAND_SIZE) |
606 |
slog (L_WARN, _("%s(%s): rand size mismatch (remote %d <=> local %d)"), |
607 |
conf->nodename, (const char *)rsi, randsize, RAND_SIZE); |
608 |
else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER ()))) |
609 |
slog (L_WARN, _("%s(%s): cipher algo mismatch (remote %x <=> local %x)"), |
610 |
conf->nodename, (const char *)rsi, ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER ())); |
611 |
else if (mac_nid != htonl (EVP_MD_type (MAC_DIGEST ()))) |
612 |
slog (L_WARN, _("%s(%s): mac algo mismatch (remote %x <=> local %x)"), |
613 |
conf->nodename, (const char *)rsi, ntohl (mac_nid), EVP_MD_type (MAC_DIGEST ())); |
614 |
else if (auth_nid != htonl (EVP_MD_type (AUTH_DIGEST ()))) |
615 |
slog (L_WARN, _("%s(%s): auth algo mismatch (remote %x <=> local %x)"), |
616 |
conf->nodename, (const char *)rsi, ntohl (auth_nid), EVP_MD_type (AUTH_DIGEST ())); |
617 |
else |
618 |
{ |
619 |
int cmp = memcmp (serial, ::conf.serial, sizeof (serial)); |
620 |
|
621 |
if (cmp > 0) |
622 |
slog (L_WARN, _("%s(%s): remote serial newer than local serial - outdated config?"), |
623 |
conf->nodename, (const char *)rsi); |
624 |
else if (cmp == 0) |
625 |
return true; |
626 |
} |
627 |
|
628 |
return false; |
629 |
} |
630 |
|
631 |
struct auth_req_packet : config_packet // UNPROTECTED |
632 |
{ |
633 |
char magic[8]; |
634 |
u8 initiate; // false if this is just an automatic reply |
635 |
u8 protocols; // supported protocols (will be patched on forward) |
636 |
u8 pad2, pad3; |
637 |
auth_encr encr; |
638 |
|
639 |
auth_req_packet (int dst, bool initiate_, u8 protocols_) |
640 |
{ |
641 |
config_packet::setup (PT_AUTH_REQ, dst); |
642 |
memcpy (magic, MAGIC, 8); |
643 |
initiate = !!initiate_; |
644 |
protocols = protocols_; |
645 |
|
646 |
len = sizeof (*this) - sizeof (net_packet); |
647 |
} |
648 |
}; |
649 |
|
650 |
struct auth_res_packet : vpn_packet // UNPROTECTED |
651 |
{ |
652 |
auth_response response; |
653 |
|
654 |
auth_res_packet (int dst) |
655 |
{ |
656 |
set_hdr (PT_AUTH_RES, dst); |
657 |
|
658 |
len = sizeof (*this) - sizeof (net_packet); |
659 |
} |
660 |
}; |
661 |
|
662 |
struct connect_req_packet : vpn_packet |
663 |
{ |
664 |
u8 id, protocols; |
665 |
u8 pad1, pad2; |
666 |
|
667 |
connect_req_packet (int dst, int id_, u8 protocols_) |
668 |
: id(id_) |
669 |
, protocols(protocols_) |
670 |
{ |
671 |
set_hdr (PT_CONNECT_REQ, dst); |
672 |
len = sizeof (*this) - sizeof (net_packet); |
673 |
} |
674 |
}; |
675 |
|
676 |
struct connect_info_packet : vpn_packet |
677 |
{ |
678 |
u8 id, protocols; |
679 |
u8 pad1, pad2; |
680 |
sockinfo si; |
681 |
|
682 |
connect_info_packet (int dst, int id_, const sockinfo &si_, u8 protocols_) |
683 |
: id(id_) |
684 |
, protocols(protocols_) |
685 |
, si(si_) |
686 |
{ |
687 |
set_hdr (PT_CONNECT_INFO, dst); |
688 |
|
689 |
len = sizeof (*this) - sizeof (net_packet); |
690 |
} |
691 |
}; |
692 |
|
693 |
///////////////////////////////////////////////////////////////////////////// |
694 |
|
695 |
void |
696 |
connection::connection_established (const sockinfo &rsi) |
697 |
{ |
698 |
if (!have_snd_auth || !have_rcv_auth) |
699 |
return; |
700 |
|
701 |
si = rsi; |
702 |
protocol = rsi.prot; |
703 |
|
704 |
slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), |
705 |
conf->nodename, (const char *)rsi, |
706 |
vpn->can_direct (THISNODE, conf) ? "direct" : "forwarded", |
707 |
PROTOCOL_MAJOR, prot_minor); |
708 |
|
709 |
if (::conf.script_node_up) |
710 |
{ |
711 |
run_script_cb *cb = new run_script_cb; |
712 |
cb->set<connection, &connection::script_node_up> (this); |
713 |
run_script_queued (cb, _("node-up command execution failed, continuing.")); |
714 |
} |
715 |
|
716 |
delete ictx; ictx = new crypto_ctx (rcv_auth, snd_auth, rcv_ecdh_a, rcv_auth.ecdh, 0); |
717 |
iseqno.reset (ntohl (rcv_auth.rsa.seqno) & 0x7fffffff); |
718 |
|
719 |
delete octx; octx = new crypto_ctx (snd_auth, rcv_auth, snd_ecdh_a, snd_ecdh_b , 1); |
720 |
oseqno = ntohl (snd_auth.rsa.seqno) & 0x7fffffff; |
721 |
|
722 |
oiv.reset (); |
723 |
|
724 |
// make sure rekeying timeouts are slightly asymmetric |
725 |
ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); |
726 |
rekey.start (rekey_interval, rekey_interval); |
727 |
|
728 |
hmac_error = 0.; |
729 |
|
730 |
keepalive.start (::conf.keepalive); |
731 |
|
732 |
// send queued packets |
733 |
while (tap_packet *p = (tap_packet *)data_queue.get ()) |
734 |
{ |
735 |
if (p->len) send_data_packet (p); |
736 |
delete p; |
737 |
} |
738 |
|
739 |
while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
740 |
{ |
741 |
if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); |
742 |
delete p; |
743 |
} |
744 |
|
745 |
vpn->connection_established (this); |
746 |
} |
747 |
|
748 |
void |
749 |
connection::reset_si () |
750 |
{ |
751 |
if (vpn->can_direct (THISNODE, conf)) |
752 |
protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ()); |
753 |
else |
754 |
{ |
755 |
slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename); |
756 |
protocol = 0; |
757 |
} |
758 |
|
759 |
si.set (conf, protocol); |
760 |
} |
761 |
|
762 |
// ensure sockinfo is valid, forward if necessary |
763 |
const sockinfo & |
764 |
connection::forward_si (const sockinfo &si) const |
765 |
{ |
766 |
if (!si.valid ()) |
767 |
{ |
768 |
connection *r = vpn->find_router_for (this); |
769 |
|
770 |
if (r) |
771 |
{ |
772 |
slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."), |
773 |
conf->nodename, r->conf->nodename); |
774 |
return r->si; |
775 |
} |
776 |
else |
777 |
slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."), |
778 |
conf->nodename); |
779 |
} |
780 |
|
781 |
return si; |
782 |
} |
783 |
|
784 |
void |
785 |
connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
786 |
{ |
787 |
if (!vpn->send_vpn_packet (pkt, si, tos)) |
788 |
reset_connection ("packet send error"); |
789 |
} |
790 |
|
791 |
void |
792 |
connection::send_ping (const sockinfo &si, u8 pong) |
793 |
{ |
794 |
ping_packet *pkt = new ping_packet; |
795 |
|
796 |
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
797 |
|
798 |
slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); |
799 |
send_vpn_packet (pkt, si, IPTOS_LOWDELAY); |
800 |
|
801 |
delete pkt; |
802 |
} |
803 |
|
804 |
void |
805 |
connection::send_reset (const sockinfo &si) |
806 |
{ |
807 |
if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED) |
808 |
{ |
809 |
config_packet *pkt = new config_packet; |
810 |
|
811 |
pkt->setup (vpn_packet::PT_RESET, conf->id); |
812 |
send_vpn_packet (pkt, si, IPTOS_MINCOST); |
813 |
|
814 |
delete pkt; |
815 |
} |
816 |
} |
817 |
|
818 |
void |
819 |
connection::send_auth_request (const sockinfo &si, bool initiate) |
820 |
{ |
821 |
auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); |
822 |
|
823 |
generate_auth_data (); |
824 |
auth_encrypt (conf->rsa_key, snd_auth, pkt->encr); |
825 |
|
826 |
slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); |
827 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly |
828 |
|
829 |
delete pkt; |
830 |
} |
831 |
|
832 |
void |
833 |
connection::send_auth_response (const sockinfo &si) |
834 |
{ |
835 |
auth_res_packet *pkt = new auth_res_packet (conf->id); |
836 |
|
837 |
memcpy (pkt->response.ecdh, rcv_ecdh_b, sizeof rcv_ecdh_b); |
838 |
auth_hash (rcv_auth, rcv_ecdh_b, pkt->response.mac); |
839 |
|
840 |
slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); |
841 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
842 |
|
843 |
delete pkt; |
844 |
} |
845 |
|
846 |
void |
847 |
connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) |
848 |
{ |
849 |
slog (L_TRACE, "%s << PT_CONNECT_INFO(%s,%s,p%02x)", conf->nodename, |
850 |
vpn->conns[rid - 1]->conf->nodename, (const char *)rsi, |
851 |
conf->protocols); |
852 |
|
853 |
connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); |
854 |
|
855 |
r->hmac_set (octx); |
856 |
send_vpn_packet (r, si); |
857 |
|
858 |
delete r; |
859 |
} |
860 |
|
861 |
inline void |
862 |
connection::establish_connection_cb (ev::timer &w, int revents) |
863 |
{ |
864 |
if (!(ictx && octx) |
865 |
&& conf != THISNODE |
866 |
&& connectmode != conf_node::C_NEVER |
867 |
&& connectmode != conf_node::C_DISABLED |
868 |
&& !w.is_active ()) |
869 |
{ |
870 |
// a bit hacky, if ondemand, and packets are no longer queued, then reset the connection |
871 |
// and stop trying. should probably be handled by a per-connection expire handler. |
872 |
if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ()) |
873 |
{ |
874 |
reset_connection ("no demand"); |
875 |
return; |
876 |
} |
877 |
|
878 |
last_establish_attempt = ev_now (); |
879 |
|
880 |
ev::tstamp retry_int = ev::tstamp (retry_cnt & 3 |
881 |
? (retry_cnt & 3) + 1 |
882 |
: 1 << (retry_cnt >> 2)); |
883 |
|
884 |
reset_si (); |
885 |
|
886 |
bool slow = si.prot & PROT_SLOW; |
887 |
|
888 |
if (si.prot && !si.host && vpn->can_direct (THISNODE, conf)) |
889 |
{ |
890 |
/*TODO*/ /* start the timer so we don't recurse endlessly */ |
891 |
w.start (1); |
892 |
vpn->send_connect_request (this); |
893 |
} |
894 |
else |
895 |
{ |
896 |
if (si.valid ()) |
897 |
slog (L_DEBUG, _("%s: sending direct connection request to %s."), |
898 |
conf->nodename, (const char *)si); |
899 |
|
900 |
const sockinfo &dsi = forward_si (si); |
901 |
|
902 |
slow = slow || (dsi.prot & PROT_SLOW); |
903 |
|
904 |
if (dsi.valid () && auth_rate_limiter.can (dsi)) |
905 |
{ |
906 |
if (retry_cnt < 4) |
907 |
send_auth_request (dsi, true); |
908 |
else |
909 |
send_ping (dsi, 0); |
910 |
} |
911 |
} |
912 |
|
913 |
retry_int *= slow ? 8. : 0.9; |
914 |
|
915 |
if (retry_int < conf->max_retry) |
916 |
retry_cnt++; |
917 |
else |
918 |
retry_int = conf->max_retry; |
919 |
|
920 |
w.start (retry_int); |
921 |
} |
922 |
} |
923 |
|
924 |
void |
925 |
connection::reset_connection (const char *reason) |
926 |
{ |
927 |
if (ictx && octx) |
928 |
{ |
929 |
slog (L_INFO, _("%s(%s): connection lost (%s)"), |
930 |
conf->nodename, (const char *)si, reason); |
931 |
|
932 |
if (::conf.script_node_down) |
933 |
{ |
934 |
run_script_cb *cb = new run_script_cb; |
935 |
cb->set<connection, &connection::script_node_down> (this); |
936 |
run_script_queued (cb, _("node-down command execution failed, continuing.")); |
937 |
} |
938 |
} |
939 |
|
940 |
delete ictx; ictx = 0; |
941 |
delete octx; octx = 0; |
942 |
|
943 |
si.host = 0; |
944 |
|
945 |
have_snd_auth = false; |
946 |
have_rcv_auth = false; |
947 |
auth_expire = 0.; |
948 |
|
949 |
last_activity = 0.; |
950 |
//last_si_change = 0.; |
951 |
retry_cnt = 0; |
952 |
|
953 |
rekey.stop (); |
954 |
keepalive.stop (); |
955 |
establish_connection.stop (); |
956 |
} |
957 |
|
958 |
void |
959 |
connection::shutdown () |
960 |
{ |
961 |
if (ictx && octx) |
962 |
send_reset (si); |
963 |
|
964 |
reset_connection ("shutdown"); |
965 |
} |
966 |
|
967 |
// poor-man's rekeying |
968 |
inline void |
969 |
connection::rekey_cb (ev::timer &w, int revents) |
970 |
{ |
971 |
reset_connection ("rekeying"); |
972 |
establish_connection (); |
973 |
} |
974 |
|
975 |
void |
976 |
connection::send_data_packet (tap_packet *pkt) |
977 |
{ |
978 |
vpndata_packet *p = new vpndata_packet; |
979 |
int tos = 0; |
980 |
|
981 |
// I am not hilarious about peeking into packets, but so be it. |
982 |
if (conf->inherit_tos && pkt->is_ipv4 ()) |
983 |
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
984 |
|
985 |
p->setup (this, conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
986 |
send_vpn_packet (p, si, tos); |
987 |
|
988 |
delete p; |
989 |
|
990 |
if (oseqno > MAX_SEQNO) |
991 |
rekey (); |
992 |
} |
993 |
|
994 |
void |
995 |
connection::post_inject_queue () |
996 |
{ |
997 |
// force a connection every now and when when packets are sent (max 1/s) |
998 |
if (ev_now () - last_establish_attempt >= 0.95) // arbitrary |
999 |
establish_connection.stop (); |
1000 |
|
1001 |
establish_connection (); |
1002 |
} |
1003 |
|
1004 |
void |
1005 |
connection::inject_data_packet (tap_packet *pkt) |
1006 |
{ |
1007 |
if (ictx && octx) |
1008 |
send_data_packet (pkt); |
1009 |
else |
1010 |
{ |
1011 |
data_queue.put (new tap_packet (*pkt)); |
1012 |
post_inject_queue (); |
1013 |
} |
1014 |
} |
1015 |
|
1016 |
void |
1017 |
connection::inject_vpn_packet (vpn_packet *pkt, int tos) |
1018 |
{ |
1019 |
if (ictx && octx) |
1020 |
send_vpn_packet (pkt, si, tos); |
1021 |
else |
1022 |
{ |
1023 |
vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); |
1024 |
post_inject_queue (); |
1025 |
} |
1026 |
} |
1027 |
|
1028 |
void |
1029 |
connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
1030 |
{ |
1031 |
last_activity = ev_now (); |
1032 |
|
1033 |
slog (L_NOISE, "%s >> received packet type %d from %d to %d.", |
1034 |
conf->nodename, pkt->typ (), pkt->src (), pkt->dst ()); |
1035 |
|
1036 |
if (connectmode == conf_node::C_DISABLED) |
1037 |
return; |
1038 |
|
1039 |
switch (pkt->typ ()) |
1040 |
{ |
1041 |
case vpn_packet::PT_PING: |
1042 |
slog (L_TRACE, "%s >> PT_PING", conf->nodename); |
1043 |
|
1044 |
// we send pings instead of auth packets after some retries, |
1045 |
// so reset the retry counter and establish a connection |
1046 |
// when we receive a ping. |
1047 |
if (!ictx) |
1048 |
{ |
1049 |
if (auth_rate_limiter.can (rsi)) |
1050 |
send_auth_request (rsi, true); |
1051 |
} |
1052 |
else |
1053 |
// we would love to change the socket address here, but ping's aren't |
1054 |
// authenticated, so we best ignore it. |
1055 |
send_ping (rsi, 1); // pong |
1056 |
|
1057 |
break; |
1058 |
|
1059 |
case vpn_packet::PT_PONG: |
1060 |
slog (L_TRACE, "%s >> PT_PONG", conf->nodename); |
1061 |
|
1062 |
// a PONG might mean that the other side doesn't really know |
1063 |
// about our desire for communication. |
1064 |
establish_connection (); |
1065 |
break; |
1066 |
|
1067 |
case vpn_packet::PT_RESET: |
1068 |
slog (L_TRACE, "%s >> PT_RESET", conf->nodename); |
1069 |
|
1070 |
if (ictx && octx) |
1071 |
{ |
1072 |
reset_connection ("remote reset"); |
1073 |
|
1074 |
config_packet *p = (config_packet *) pkt; |
1075 |
|
1076 |
if (p->chk_config (conf, rsi) && connectmode == conf_node::C_ALWAYS) |
1077 |
establish_connection (); |
1078 |
} |
1079 |
|
1080 |
break; |
1081 |
|
1082 |
case vpn_packet::PT_AUTH_REQ: |
1083 |
if (auth_rate_limiter.can (rsi)) |
1084 |
{ |
1085 |
auth_req_packet *p = (auth_req_packet *)pkt; |
1086 |
|
1087 |
slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)", |
1088 |
conf->nodename, p->initiate ? "initiate" : "reply", |
1089 |
p->protocols, p->features); |
1090 |
|
1091 |
if (memcmp (p->magic, MAGIC, 8)) |
1092 |
{ |
1093 |
slog (L_WARN, _("%s(%s): protocol magic mismatch - stray packet?"), |
1094 |
conf->nodename, (const char *)rsi); |
1095 |
} |
1096 |
else if (p->chk_config (conf, rsi)) |
1097 |
{ |
1098 |
if (p->prot_minor != PROTOCOL_MINOR) |
1099 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1100 |
conf->nodename, (const char *)rsi, |
1101 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1102 |
|
1103 |
if (p->initiate) |
1104 |
{ |
1105 |
send_auth_request (rsi, false); |
1106 |
|
1107 |
if (ictx && octx) |
1108 |
reset_connection ("reconnect"); |
1109 |
} |
1110 |
|
1111 |
auth_data auth; |
1112 |
|
1113 |
if (!auth_decrypt (::conf.rsa_key, p->encr, auth)) |
1114 |
{ |
1115 |
slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
1116 |
conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
1117 |
} |
1118 |
else |
1119 |
{ |
1120 |
bool chg = !have_rcv_auth || memcmp (&rcv_auth, &auth, sizeof auth); |
1121 |
|
1122 |
rcv_auth = auth; |
1123 |
have_rcv_auth = true; |
1124 |
|
1125 |
send_auth_response (rsi); |
1126 |
|
1127 |
if (chg) |
1128 |
{ |
1129 |
conf->protocols = p->protocols; |
1130 |
features = p->features & config_packet::get_features (); |
1131 |
|
1132 |
connection_established (rsi); |
1133 |
} |
1134 |
} |
1135 |
|
1136 |
break; |
1137 |
} |
1138 |
|
1139 |
send_reset (rsi); |
1140 |
} |
1141 |
|
1142 |
break; |
1143 |
|
1144 |
case vpn_packet::PT_AUTH_RES: |
1145 |
{ |
1146 |
auth_res_packet *p = (auth_res_packet *)pkt; |
1147 |
|
1148 |
slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); |
1149 |
|
1150 |
auth_mac local_mac; |
1151 |
auth_hash (snd_auth, p->response.ecdh, local_mac); |
1152 |
|
1153 |
if (memcmp (&p->response.mac, local_mac, sizeof local_mac)) |
1154 |
{ |
1155 |
slog (L_ERR, _("%s(%s): unrequested or outdated auth response, ignoring."), |
1156 |
conf->nodename, (const char *)rsi); |
1157 |
} |
1158 |
else if (!have_snd_auth) |
1159 |
{ |
1160 |
memcpy (snd_ecdh_b, p->response.ecdh, sizeof snd_ecdh_b); |
1161 |
|
1162 |
have_snd_auth = true; |
1163 |
connection_established (rsi); |
1164 |
} |
1165 |
} |
1166 |
break; |
1167 |
|
1168 |
case vpn_packet::PT_DATA_COMPRESSED: |
1169 |
#if !ENABLE_COMPRESSION |
1170 |
send_reset (rsi); |
1171 |
break; |
1172 |
#endif |
1173 |
|
1174 |
case vpn_packet::PT_DATA_UNCOMPRESSED: |
1175 |
|
1176 |
if (ictx && octx) |
1177 |
{ |
1178 |
vpndata_packet *p = (vpndata_packet *)pkt; |
1179 |
|
1180 |
if (!p->hmac_chk (ictx)) |
1181 |
{ |
1182 |
// rekeying often creates temporary hmac auth floods |
1183 |
// we assume they don't take longer than a few seconds normally, |
1184 |
// and suppress messages and resets during that time. |
1185 |
//TODO: should be done per source address |
1186 |
if (!hmac_error) |
1187 |
{ |
1188 |
hmac_error = ev_now () + 3; |
1189 |
break; |
1190 |
} |
1191 |
else if (hmac_error >= ev_now ()) |
1192 |
break; // silently suppress |
1193 |
else |
1194 |
{ |
1195 |
slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" |
1196 |
"could be an attack, or just corruption or a synchronization error."), |
1197 |
conf->nodename, (const char *)rsi); |
1198 |
// reset |
1199 |
} |
1200 |
} |
1201 |
else |
1202 |
{ |
1203 |
u32 seqno; |
1204 |
tap_packet *d = p->unpack (this, seqno); |
1205 |
int seqclass = iseqno.seqno_classify (seqno); |
1206 |
|
1207 |
hmac_error = 0; |
1208 |
|
1209 |
if (seqclass == 0) // ok |
1210 |
{ |
1211 |
vpn->tap->send (d); |
1212 |
|
1213 |
if (si != rsi) |
1214 |
{ |
1215 |
// fast re-sync on source address changes, useful especially for tcp/ip |
1216 |
//if (last_si_change < ev_now () + 5.) |
1217 |
// { |
1218 |
slog (L_INFO, _("%s(%s): changing socket address to %s."), |
1219 |
conf->nodename, (const char *)si, (const char *)rsi); |
1220 |
|
1221 |
si = rsi; |
1222 |
|
1223 |
if (::conf.script_node_change) |
1224 |
{ |
1225 |
run_script_cb *cb = new run_script_cb; |
1226 |
cb->set<connection, &connection::script_node_change> (this); |
1227 |
run_script_queued (cb, _("node-change command execution failed, continuing.")); |
1228 |
} |
1229 |
|
1230 |
// } |
1231 |
//else |
1232 |
// slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."), |
1233 |
// conf->nodename, (const char *)si, (const char *)rsi); |
1234 |
} |
1235 |
} |
1236 |
else if (seqclass == 1) // far history |
1237 |
slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). " |
1238 |
"possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1); |
1239 |
else if (seqclass == 2) // in-window duplicate, happens often on wireless |
1240 |
slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). " |
1241 |
"possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1); |
1242 |
else if (seqclass == 3) // reset |
1243 |
{ |
1244 |
slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). " |
1245 |
"probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1); |
1246 |
send_reset (rsi); |
1247 |
} |
1248 |
|
1249 |
delete d; |
1250 |
break; |
1251 |
} |
1252 |
} |
1253 |
|
1254 |
send_reset (rsi); |
1255 |
break; |
1256 |
|
1257 |
case vpn_packet::PT_CONNECT_REQ: |
1258 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1259 |
{ |
1260 |
connect_req_packet *p = (connect_req_packet *)pkt; |
1261 |
|
1262 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1263 |
{ |
1264 |
connection *c = vpn->conns[p->id - 1]; |
1265 |
conf->protocols = p->protocols; |
1266 |
|
1267 |
slog (L_TRACE, "%s >> PT_CONNECT_REQ(%s,p%02x) [%d]", |
1268 |
conf->nodename, vpn->conns[p->id - 1]->conf->nodename, |
1269 |
p->protocols, |
1270 |
c->ictx && c->octx); |
1271 |
|
1272 |
if (c->ictx && c->octx) |
1273 |
{ |
1274 |
// send connect_info packets to both sides, in case one is |
1275 |
// behind a nat firewall (or both ;) |
1276 |
c->send_connect_info (conf->id, si, conf->protocols); |
1277 |
send_connect_info (c->conf->id, c->si, c->conf->protocols); |
1278 |
} |
1279 |
else |
1280 |
c->establish_connection (); |
1281 |
} |
1282 |
else |
1283 |
slog (L_WARN, |
1284 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1285 |
p->id); |
1286 |
} |
1287 |
|
1288 |
break; |
1289 |
|
1290 |
case vpn_packet::PT_CONNECT_INFO: |
1291 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1292 |
{ |
1293 |
connect_info_packet *p = (connect_info_packet *)pkt; |
1294 |
|
1295 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1296 |
{ |
1297 |
connection *c = vpn->conns[p->id - 1]; |
1298 |
|
1299 |
c->conf->protocols = p->protocols; |
1300 |
protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); |
1301 |
p->si.upgrade_protocol (protocol, c->conf); |
1302 |
|
1303 |
slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s,protocols=%02x,protocol=%02x,upgradable=%02x) [%d]", |
1304 |
conf->nodename, |
1305 |
vpn->conns[p->id - 1]->conf->nodename, |
1306 |
(const char *)p->si, |
1307 |
p->protocols, |
1308 |
protocol, |
1309 |
p->si.supported_protocols (c->conf), |
1310 |
!c->ictx && !c->octx); |
1311 |
|
1312 |
const sockinfo &dsi = forward_si (p->si); |
1313 |
|
1314 |
if (dsi.valid ()) |
1315 |
c->send_auth_request (dsi, true); |
1316 |
else |
1317 |
slog (L_INFO, "connect info for %s received (%s), but still unable to contact.", |
1318 |
vpn->conns[p->id - 1]->conf->nodename, |
1319 |
(const char *)p->si); |
1320 |
} |
1321 |
else |
1322 |
slog (L_WARN, |
1323 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1324 |
p->id); |
1325 |
} |
1326 |
|
1327 |
break; |
1328 |
|
1329 |
default: |
1330 |
send_reset (rsi); |
1331 |
break; |
1332 |
} |
1333 |
} |
1334 |
|
1335 |
inline void |
1336 |
connection::keepalive_cb (ev::timer &w, int revents) |
1337 |
{ |
1338 |
ev_tstamp when = last_activity + ::conf.keepalive - ev::now (); |
1339 |
|
1340 |
if (when >= 0) |
1341 |
w.start (when); |
1342 |
else if (when < -15) |
1343 |
{ |
1344 |
reset_connection ("keepalive overdue"); |
1345 |
establish_connection (); |
1346 |
} |
1347 |
else if (conf->connectmode != conf_node::C_ONDEMAND |
1348 |
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
1349 |
{ |
1350 |
w.start (3); |
1351 |
send_ping (si); |
1352 |
} |
1353 |
else if (when >= -10) |
1354 |
// hold ondemand connections implicitly a few seconds longer |
1355 |
// should delete octx, though, or something like that ;) |
1356 |
w.start (when + 10); |
1357 |
else |
1358 |
reset_connection ("keepalive timeout"); |
1359 |
} |
1360 |
|
1361 |
void |
1362 |
connection::send_connect_request (int id) |
1363 |
{ |
1364 |
connect_req_packet *p = new connect_req_packet (conf->id, id, THISNODE->protocols); |
1365 |
|
1366 |
slog (L_TRACE, "%s << PT_CONNECT_REQ(%s,p%02x)", |
1367 |
conf->nodename, vpn->conns[id - 1]->conf->nodename, |
1368 |
THISNODE->protocols); |
1369 |
p->hmac_set (octx); |
1370 |
send_vpn_packet (p, si); |
1371 |
|
1372 |
delete p; |
1373 |
} |
1374 |
|
1375 |
void |
1376 |
connection::script_init_env (const char *ext) |
1377 |
{ |
1378 |
char *env; |
1379 |
asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env); |
1380 |
asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env); |
1381 |
asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext, |
1382 |
0xfe, 0xfd, 0x80, 0x00, conf->id >> 8, |
1383 |
conf->id & 0xff); putenv (env); |
1384 |
} |
1385 |
|
1386 |
void |
1387 |
connection::script_init_connect_env () |
1388 |
{ |
1389 |
vpn->script_init_env (); |
1390 |
|
1391 |
char *env; |
1392 |
asprintf (&env, "DESTID=%d", conf->id); putenv (env); |
1393 |
asprintf (&env, "DESTSI=%s", (const char *)si); putenv (env); |
1394 |
asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); |
1395 |
asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); |
1396 |
asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); |
1397 |
} |
1398 |
|
1399 |
inline const char * |
1400 |
connection::script_node_up () |
1401 |
{ |
1402 |
script_init_connect_env (); |
1403 |
|
1404 |
putenv ((char *)"STATE=up"); |
1405 |
|
1406 |
char *filename; |
1407 |
asprintf (&filename, |
1408 |
"%s/%s", |
1409 |
confbase, |
1410 |
::conf.script_node_up ? ::conf.script_node_up : "node-up"); |
1411 |
|
1412 |
return filename; |
1413 |
} |
1414 |
|
1415 |
inline const char * |
1416 |
connection::script_node_change () |
1417 |
{ |
1418 |
script_init_connect_env (); |
1419 |
|
1420 |
putenv ((char *)"STATE=change"); |
1421 |
|
1422 |
char *filename; |
1423 |
asprintf (&filename, |
1424 |
"%s/%s", |
1425 |
confbase, |
1426 |
::conf.script_node_change ? ::conf.script_node_change : "node-change"); |
1427 |
|
1428 |
return filename; |
1429 |
} |
1430 |
|
1431 |
inline const char * |
1432 |
connection::script_node_down () |
1433 |
{ |
1434 |
script_init_connect_env (); |
1435 |
|
1436 |
putenv ((char *)"STATE=down"); |
1437 |
|
1438 |
char *filename; |
1439 |
asprintf (&filename, |
1440 |
"%s/%s", |
1441 |
confbase, |
1442 |
::conf.script_node_down ? ::conf.script_node_down : "node-down"); |
1443 |
|
1444 |
return filename; |
1445 |
} |
1446 |
|
1447 |
connection::connection (struct vpn *vpn, conf_node *conf) |
1448 |
: vpn(vpn), conf(conf), |
1449 |
#if ENABLE_DNS |
1450 |
dns (0), |
1451 |
#endif |
1452 |
data_queue(conf->max_ttl, conf->max_queue + 1), |
1453 |
vpn_queue(conf->max_ttl, conf->max_queue + 1) |
1454 |
{ |
1455 |
rekey .set<connection, &connection::rekey_cb > (this); |
1456 |
keepalive .set<connection, &connection::keepalive_cb > (this); |
1457 |
establish_connection.set<connection, &connection::establish_connection_cb> (this); |
1458 |
|
1459 |
last_establish_attempt = 0.; |
1460 |
octx = ictx = 0; |
1461 |
|
1462 |
connectmode = conf->connectmode; |
1463 |
|
1464 |
// queue a dummy packet to force an initial connection attempt |
1465 |
if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED) |
1466 |
vpn_queue.put (new net_packet); |
1467 |
|
1468 |
reset_connection ("startup"); |
1469 |
} |
1470 |
|
1471 |
connection::~connection () |
1472 |
{ |
1473 |
shutdown (); |
1474 |
} |
1475 |
|
1476 |
void |
1477 |
connection_init () |
1478 |
{ |
1479 |
auth_rate_limiter.clear (); |
1480 |
reset_rate_limiter.clear (); |
1481 |
} |
1482 |
|