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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/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 "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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require (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, auth_mac &mac) |
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{ |
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HMAC_CTX ctx; |
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|
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HMAC_CTX_init (&ctx); |
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require (HMAC_Init_ex (&ctx, auth.rsa.auth_key, sizeof (auth.rsa.auth_key), AUTH_DIGEST (), 0)); |
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require (HMAC_Update (&ctx, (const unsigned char *)&auth, sizeof auth)); |
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require (HMAC_Final (&ctx, (unsigned char *)&mac, 0)); |
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HMAC_CTX_cleanup (&ctx); |
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} |
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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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auth_hash (snd_auth, snd_auth_mac); |
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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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} |
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|
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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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////////////////////////////////////////////////////////////////////////////// |
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|
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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]; |
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|
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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); |
223 |
} |
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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; |
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|
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delete [] queue; |
231 |
} |
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|
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void |
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pkt_queue::expire_cb (ev::timer &w, int revents) |
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{ |
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ev_tstamp expire = ev_now () - max_ttl; |
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|
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for (;;) |
239 |
{ |
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if (empty ()) |
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break; |
242 |
|
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double diff = queue[j].tstamp - expire; |
244 |
|
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if (diff >= 0.) |
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{ |
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w.start (diff > 0.5 ? diff : 0.5); |
248 |
break; |
249 |
} |
250 |
|
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delete get (); |
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} |
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} |
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|
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void |
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pkt_queue::put (net_packet *p) |
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{ |
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ev_tstamp now = ev_now (); |
259 |
|
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// start expiry timer |
261 |
if (empty ()) |
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expire.start (max_ttl); |
263 |
|
264 |
int ni = i + 1 == max_queue ? 0 : i + 1; |
265 |
|
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if (ni == j) |
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delete get (); |
268 |
|
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queue[i].pkt = p; |
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queue[i].tstamp = now; |
271 |
|
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i = ni; |
273 |
} |
274 |
|
275 |
net_packet * |
276 |
pkt_queue::get () |
277 |
{ |
278 |
if (empty ()) |
279 |
return 0; |
280 |
|
281 |
net_packet *p = queue[j].pkt; |
282 |
queue[j].pkt = 0; |
283 |
|
284 |
j = j + 1 == max_queue ? 0 : j + 1; |
285 |
|
286 |
return p; |
287 |
} |
288 |
|
289 |
struct net_rateinfo |
290 |
{ |
291 |
u32 host; |
292 |
double pcnt, diff; |
293 |
tstamp last; |
294 |
}; |
295 |
|
296 |
// only do action once every x seconds per host whole allowing bursts. |
297 |
// this implementation ("splay list" ;) is inefficient, |
298 |
// but low on resources. |
299 |
struct net_rate_limiter : list<net_rateinfo> |
300 |
{ |
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# define NRL_ALPHA (1. - 1. / 600.) // allow bursts |
302 |
# define NRL_CUTOFF 10. // one event every CUTOFF seconds |
303 |
# define NRL_EXPIRE (NRL_CUTOFF * 30.) // expire entries after this time |
304 |
# define NRL_MAXDIF (NRL_CUTOFF * (1. / (1. - NRL_ALPHA))) // maximum diff /count value |
305 |
|
306 |
bool can (const sockinfo &si) { return can((u32)si.host); } |
307 |
bool can (u32 host); |
308 |
}; |
309 |
|
310 |
static net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
311 |
|
312 |
bool |
313 |
net_rate_limiter::can (u32 host) |
314 |
{ |
315 |
iterator i; |
316 |
|
317 |
for (i = begin (); i != end (); ) |
318 |
if (i->host == host) |
319 |
break; |
320 |
else if (i->last < ev_now () - NRL_EXPIRE) |
321 |
i = erase (i); |
322 |
else |
323 |
i++; |
324 |
|
325 |
if (i == end ()) |
326 |
{ |
327 |
net_rateinfo ri; |
328 |
|
329 |
ri.host = host; |
330 |
ri.pcnt = 1.; |
331 |
ri.diff = NRL_MAXDIF; |
332 |
ri.last = ev_now (); |
333 |
|
334 |
push_front (ri); |
335 |
|
336 |
return true; |
337 |
} |
338 |
else |
339 |
{ |
340 |
net_rateinfo ri (*i); |
341 |
erase (i); |
342 |
|
343 |
ri.pcnt = ri.pcnt * NRL_ALPHA; |
344 |
ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last); |
345 |
|
346 |
ri.last = ev_now (); |
347 |
|
348 |
double dif = ri.diff / ri.pcnt; |
349 |
|
350 |
bool send = dif > NRL_CUTOFF; |
351 |
|
352 |
if (dif > NRL_MAXDIF) |
353 |
{ |
354 |
ri.pcnt = 1.; |
355 |
ri.diff = NRL_MAXDIF; |
356 |
} |
357 |
else if (send) |
358 |
ri.pcnt++; |
359 |
|
360 |
push_front (ri); |
361 |
|
362 |
return send; |
363 |
} |
364 |
} |
365 |
|
366 |
///////////////////////////////////////////////////////////////////////////// |
367 |
|
368 |
unsigned char hmac_packet::hmac_digest[EVP_MAX_MD_SIZE]; |
369 |
|
370 |
void |
371 |
hmac_packet::hmac_gen (crypto_ctx *ctx) |
372 |
{ |
373 |
unsigned int xlen; |
374 |
|
375 |
HMAC_CTX *hctx = &ctx->hctx; |
376 |
|
377 |
require (HMAC_Init_ex (hctx, 0, 0, 0, 0)); |
378 |
require (HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), |
379 |
len - sizeof (hmac_packet))); |
380 |
require (HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen)); |
381 |
} |
382 |
|
383 |
void |
384 |
hmac_packet::hmac_set (crypto_ctx *ctx) |
385 |
{ |
386 |
hmac_gen (ctx); |
387 |
|
388 |
memcpy (hmac, hmac_digest, HMACLENGTH); |
389 |
} |
390 |
|
391 |
bool |
392 |
hmac_packet::hmac_chk (crypto_ctx *ctx) |
393 |
{ |
394 |
hmac_gen (ctx); |
395 |
|
396 |
return !memcmp (hmac, hmac_digest, HMACLENGTH); |
397 |
} |
398 |
|
399 |
void |
400 |
vpn_packet::set_hdr (ptype type_, unsigned int dst) |
401 |
{ |
402 |
type = type_; |
403 |
|
404 |
int src = THISNODE->id; |
405 |
|
406 |
src1 = src; |
407 |
srcdst = ((src >> 8) << 4) | (dst >> 8); |
408 |
dst1 = dst; |
409 |
} |
410 |
|
411 |
#define MAXVPNDATA (MAX_MTU - 6 - 6) |
412 |
#define DATAHDR (sizeof (u32) + RAND_SIZE) |
413 |
|
414 |
struct vpndata_packet : vpn_packet |
415 |
{ |
416 |
u8 data[MAXVPNDATA + DATAHDR]; // seqno |
417 |
|
418 |
void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno); |
419 |
tap_packet *unpack (connection *conn, u32 &seqno); |
420 |
|
421 |
private: |
422 |
const u32 data_hdr_size () const |
423 |
{ |
424 |
return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; |
425 |
} |
426 |
}; |
427 |
|
428 |
void |
429 |
vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
430 |
{ |
431 |
EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
432 |
int outl = 0, outl2; |
433 |
ptype type = PT_DATA_UNCOMPRESSED; |
434 |
|
435 |
#if ENABLE_COMPRESSION |
436 |
u8 cdata[MAX_MTU]; |
437 |
|
438 |
if (conn->features & FEATURE_COMPRESSION) |
439 |
{ |
440 |
u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
441 |
|
442 |
if (cl) |
443 |
{ |
444 |
type = PT_DATA_COMPRESSED; |
445 |
d = cdata; |
446 |
l = cl + 2; |
447 |
|
448 |
d[0] = cl >> 8; |
449 |
d[1] = cl; |
450 |
} |
451 |
} |
452 |
#endif |
453 |
|
454 |
require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 1)); |
455 |
|
456 |
struct { |
457 |
#if RAND_SIZE |
458 |
u8 rnd[RAND_SIZE]; |
459 |
#endif |
460 |
u32 seqno; |
461 |
} datahdr; |
462 |
|
463 |
datahdr.seqno = ntohl (seqno); |
464 |
#if RAND_SIZE |
465 |
// NB: a constant (per session) random prefix |
466 |
// is likely enough, but we don't take any chances. |
467 |
conn->oiv.get (datahdr.rnd, RAND_SIZE); |
468 |
#endif |
469 |
|
470 |
require (EVP_EncryptUpdate (cctx, |
471 |
(unsigned char *) data + outl, &outl2, |
472 |
(unsigned char *) &datahdr, DATAHDR)); |
473 |
outl += outl2; |
474 |
|
475 |
require (EVP_EncryptUpdate (cctx, |
476 |
(unsigned char *) data + outl, &outl2, |
477 |
(unsigned char *) d, l)); |
478 |
outl += outl2; |
479 |
|
480 |
require (EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2)); |
481 |
outl += outl2; |
482 |
|
483 |
len = outl + data_hdr_size (); |
484 |
|
485 |
set_hdr (type, dst); |
486 |
|
487 |
hmac_set (conn->octx); |
488 |
} |
489 |
|
490 |
tap_packet * |
491 |
vpndata_packet::unpack (connection *conn, u32 &seqno) |
492 |
{ |
493 |
EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; |
494 |
int outl = 0, outl2; |
495 |
tap_packet *p = new tap_packet; |
496 |
u8 *d; |
497 |
u32 l = len - data_hdr_size (); |
498 |
|
499 |
require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 0)); |
500 |
|
501 |
#if ENABLE_COMPRESSION |
502 |
u8 cdata[MAX_MTU]; |
503 |
|
504 |
if (type == PT_DATA_COMPRESSED) |
505 |
d = cdata; |
506 |
else |
507 |
#endif |
508 |
d = &(*p)[6 + 6] - DATAHDR; |
509 |
|
510 |
// we play do evil games with the struct layout atm. |
511 |
// pending better solutions, we at least do some verification. |
512 |
// this is fine, as we left ISO territory long ago. |
513 |
require (DATAHDR <= 16); |
514 |
require ((u8 *)(&p->len + 1) == &(*p)[0]); |
515 |
|
516 |
// this can overwrite the len/dst/src fields |
517 |
require (EVP_DecryptUpdate (cctx, |
518 |
d, &outl2, |
519 |
(unsigned char *)&data, len - data_hdr_size ())); |
520 |
outl += outl2; |
521 |
|
522 |
require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2)); |
523 |
outl += outl2; |
524 |
|
525 |
seqno = ntohl (*(u32 *)(d + RAND_SIZE)); |
526 |
|
527 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
528 |
id2mac (src (), p->src); |
529 |
|
530 |
#if ENABLE_COMPRESSION |
531 |
if (type == PT_DATA_COMPRESSED) |
532 |
{ |
533 |
u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; |
534 |
|
535 |
p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0, |
536 |
&(*p)[6 + 6], MAX_MTU) |
537 |
+ 6 + 6; |
538 |
} |
539 |
else |
540 |
p->len = outl + (6 + 6 - DATAHDR); |
541 |
#endif |
542 |
|
543 |
return p; |
544 |
} |
545 |
|
546 |
struct ping_packet : vpn_packet |
547 |
{ |
548 |
void setup (int dst, ptype type) |
549 |
{ |
550 |
set_hdr (type, dst); |
551 |
len = sizeof (*this) - sizeof (net_packet); |
552 |
} |
553 |
}; |
554 |
|
555 |
struct config_packet : vpn_packet |
556 |
{ |
557 |
u8 serial[SERIAL_SIZE]; |
558 |
u8 prot_major, prot_minor, randsize; |
559 |
u8 flags, features, pad6, pad7, pad8; |
560 |
u32 cipher_nid, mac_nid, auth_nid; |
561 |
|
562 |
void setup (ptype type, int dst); |
563 |
bool chk_config (const conf_node *conf, const sockinfo &rsi) const; |
564 |
|
565 |
static u8 get_features () |
566 |
{ |
567 |
u8 f = 0; |
568 |
#if ENABLE_COMPRESSION |
569 |
f |= FEATURE_COMPRESSION; |
570 |
#endif |
571 |
#if ENABLE_ROHC |
572 |
f |= FEATURE_ROHC; |
573 |
#endif |
574 |
#if ENABLE_BRIDGING |
575 |
f |= FEATURE_BRIDGING; |
576 |
#endif |
577 |
return f; |
578 |
} |
579 |
}; |
580 |
|
581 |
void |
582 |
config_packet::setup (ptype type, int dst) |
583 |
{ |
584 |
prot_major = PROTOCOL_MAJOR; |
585 |
prot_minor = PROTOCOL_MINOR; |
586 |
randsize = RAND_SIZE; |
587 |
flags = 0; |
588 |
features = get_features (); |
589 |
|
590 |
strncpy ((char *)serial, conf.serial, sizeof (serial)); |
591 |
|
592 |
cipher_nid = htonl (EVP_CIPHER_nid (CIPHER ())); |
593 |
mac_nid = htonl (EVP_MD_type (MAC_DIGEST ())); |
594 |
auth_nid = htonl (EVP_MD_type (AUTH_DIGEST ())); |
595 |
|
596 |
len = sizeof (*this) - sizeof (net_packet); |
597 |
set_hdr (type, dst); |
598 |
} |
599 |
|
600 |
bool |
601 |
config_packet::chk_config (const conf_node *conf, const sockinfo &rsi) const |
602 |
{ |
603 |
if (prot_major != PROTOCOL_MAJOR) |
604 |
slog (L_WARN, _("%s(%s): major version mismatch (remote %d <=> local %d)"), |
605 |
conf->nodename, (const char *)rsi, prot_major, PROTOCOL_MAJOR); |
606 |
else if (randsize != RAND_SIZE) |
607 |
slog (L_WARN, _("%s(%s): rand size mismatch (remote %d <=> local %d)"), |
608 |
conf->nodename, (const char *)rsi, randsize, RAND_SIZE); |
609 |
else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER ()))) |
610 |
slog (L_WARN, _("%s(%s): cipher algo mismatch (remote %x <=> local %x)"), |
611 |
conf->nodename, (const char *)rsi, ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER ())); |
612 |
else if (mac_nid != htonl (EVP_MD_type (MAC_DIGEST ()))) |
613 |
slog (L_WARN, _("%s(%s): mac algo mismatch (remote %x <=> local %x)"), |
614 |
conf->nodename, (const char *)rsi, ntohl (mac_nid), EVP_MD_type (MAC_DIGEST ())); |
615 |
else if (auth_nid != htonl (EVP_MD_type (AUTH_DIGEST ()))) |
616 |
slog (L_WARN, _("%s(%s): auth algo mismatch (remote %x <=> local %x)"), |
617 |
conf->nodename, (const char *)rsi, ntohl (auth_nid), EVP_MD_type (AUTH_DIGEST ())); |
618 |
else |
619 |
{ |
620 |
int cmp = memcmp (serial, ::conf.serial, sizeof (serial)); |
621 |
|
622 |
if (cmp > 0) |
623 |
slog (L_WARN, _("%s(%s): remote serial newer than local serial - outdated config?"), |
624 |
conf->nodename, (const char *)rsi); |
625 |
else if (cmp == 0) |
626 |
return true; |
627 |
} |
628 |
|
629 |
return false; |
630 |
} |
631 |
|
632 |
struct auth_req_packet : config_packet // UNPROTECTED |
633 |
{ |
634 |
char magic[8]; |
635 |
u8 initiate; // false if this is just an automatic reply |
636 |
u8 protocols; // supported protocols (will be patched on forward) |
637 |
u8 pad2, pad3; |
638 |
auth_encr encr; |
639 |
|
640 |
auth_req_packet (int dst, bool initiate_, u8 protocols_) |
641 |
{ |
642 |
config_packet::setup (PT_AUTH_REQ, dst); |
643 |
memcpy (magic, MAGIC, 8); |
644 |
initiate = !!initiate_; |
645 |
protocols = protocols_; |
646 |
|
647 |
len = sizeof (*this) - sizeof (net_packet); |
648 |
} |
649 |
}; |
650 |
|
651 |
struct auth_res_packet : vpn_packet // UNPROTECTED |
652 |
{ |
653 |
auth_response response; |
654 |
|
655 |
auth_res_packet (int dst) |
656 |
{ |
657 |
set_hdr (PT_AUTH_RES, dst); |
658 |
|
659 |
len = sizeof (*this) - sizeof (net_packet); |
660 |
} |
661 |
}; |
662 |
|
663 |
struct connect_req_packet : vpn_packet |
664 |
{ |
665 |
u8 id, protocols; |
666 |
u8 pad1, pad2; |
667 |
|
668 |
connect_req_packet (int dst, int id_, u8 protocols_) |
669 |
: id(id_) |
670 |
, protocols(protocols_) |
671 |
{ |
672 |
set_hdr (PT_CONNECT_REQ, dst); |
673 |
len = sizeof (*this) - sizeof (net_packet); |
674 |
} |
675 |
}; |
676 |
|
677 |
struct connect_info_packet : vpn_packet |
678 |
{ |
679 |
u8 id, protocols; |
680 |
u8 pad1, pad2; |
681 |
sockinfo si; |
682 |
|
683 |
connect_info_packet (int dst, int id_, const sockinfo &si_, u8 protocols_) |
684 |
: id(id_) |
685 |
, protocols(protocols_) |
686 |
, si(si_) |
687 |
{ |
688 |
set_hdr (PT_CONNECT_INFO, dst); |
689 |
|
690 |
len = sizeof (*this) - sizeof (net_packet); |
691 |
} |
692 |
}; |
693 |
|
694 |
///////////////////////////////////////////////////////////////////////////// |
695 |
|
696 |
void |
697 |
connection::connection_established (const sockinfo &rsi) |
698 |
{ |
699 |
if (!have_snd_auth || !have_rcv_auth) |
700 |
return; |
701 |
|
702 |
si = rsi; |
703 |
protocol = rsi.prot; |
704 |
|
705 |
slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), |
706 |
conf->nodename, (const char *)rsi, |
707 |
is_direct ? "direct" : "forwarded", |
708 |
PROTOCOL_MAJOR, prot_minor); |
709 |
|
710 |
if (::conf.script_node_up) |
711 |
{ |
712 |
run_script_cb *cb = new run_script_cb; |
713 |
cb->set<connection, &connection::script_node_up> (this); |
714 |
run_script_queued (cb, _("node-up command execution failed, continuing.")); |
715 |
} |
716 |
|
717 |
delete ictx; ictx = new crypto_ctx (rcv_auth, snd_auth, rcv_ecdh_a, rcv_auth.ecdh, 0); |
718 |
iseqno.reset (ntohl (rcv_auth.rsa.seqno) & 0x7fffffff); |
719 |
|
720 |
delete octx; octx = new crypto_ctx (snd_auth, rcv_auth, snd_ecdh_a, snd_ecdh_b , 1); |
721 |
oseqno = ntohl (snd_auth.rsa.seqno) & 0x7fffffff; |
722 |
|
723 |
oiv.reset (); |
724 |
|
725 |
// make sure rekeying timeouts are slightly asymmetric |
726 |
ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); |
727 |
rekey.start (rekey_interval, rekey_interval); |
728 |
|
729 |
keepalive.start (::conf.keepalive); |
730 |
|
731 |
// send queued packets |
732 |
if (ictx && octx) |
733 |
{ |
734 |
while (tap_packet *p = (tap_packet *)data_queue.get ()) |
735 |
{ |
736 |
if (p->len) send_data_packet (p); |
737 |
delete p; |
738 |
} |
739 |
|
740 |
while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
741 |
{ |
742 |
if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); |
743 |
delete p; |
744 |
} |
745 |
} |
746 |
|
747 |
vpn->connection_established (this); |
748 |
} |
749 |
|
750 |
void |
751 |
connection::reset_si () |
752 |
{ |
753 |
if (vpn->can_direct (THISNODE, conf)) |
754 |
protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ()); |
755 |
else |
756 |
{ |
757 |
slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename); |
758 |
protocol = 0; |
759 |
} |
760 |
|
761 |
si.set (conf, protocol); |
762 |
|
763 |
is_direct = si.valid (); |
764 |
} |
765 |
|
766 |
// ensure sockinfo is valid, forward if necessary |
767 |
const sockinfo & |
768 |
connection::forward_si (const sockinfo &si) const |
769 |
{ |
770 |
if (!si.valid ()) |
771 |
{ |
772 |
connection *r = vpn->find_router_for (this); |
773 |
|
774 |
if (r) |
775 |
{ |
776 |
slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."), |
777 |
conf->nodename, r->conf->nodename); |
778 |
return r->si; |
779 |
} |
780 |
else |
781 |
slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."), |
782 |
conf->nodename); |
783 |
} |
784 |
|
785 |
return si; |
786 |
} |
787 |
|
788 |
void |
789 |
connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
790 |
{ |
791 |
if (!vpn->send_vpn_packet (pkt, si, tos)) |
792 |
reset_connection (); |
793 |
} |
794 |
|
795 |
void |
796 |
connection::send_ping (const sockinfo &si, u8 pong) |
797 |
{ |
798 |
ping_packet *pkt = new ping_packet; |
799 |
|
800 |
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
801 |
|
802 |
slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); |
803 |
send_vpn_packet (pkt, si, IPTOS_LOWDELAY); |
804 |
|
805 |
delete pkt; |
806 |
} |
807 |
|
808 |
void |
809 |
connection::send_reset (const sockinfo &si) |
810 |
{ |
811 |
if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED) |
812 |
{ |
813 |
config_packet *pkt = new config_packet; |
814 |
|
815 |
pkt->setup (vpn_packet::PT_RESET, conf->id); |
816 |
send_vpn_packet (pkt, si, IPTOS_MINCOST); |
817 |
|
818 |
delete pkt; |
819 |
} |
820 |
} |
821 |
|
822 |
void |
823 |
connection::send_auth_request (const sockinfo &si, bool initiate) |
824 |
{ |
825 |
auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); |
826 |
|
827 |
generate_auth_data (); |
828 |
auth_encrypt (conf->rsa_key, snd_auth, pkt->encr); |
829 |
|
830 |
slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); |
831 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly |
832 |
|
833 |
delete pkt; |
834 |
} |
835 |
|
836 |
void |
837 |
connection::send_auth_response (const sockinfo &si) |
838 |
{ |
839 |
auth_res_packet *pkt = new auth_res_packet (conf->id); |
840 |
|
841 |
auth_hash (rcv_auth, pkt->response.mac); |
842 |
memcpy (pkt->response.ecdh, rcv_ecdh_b, sizeof (rcv_ecdh_b)); |
843 |
|
844 |
slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); |
845 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
846 |
|
847 |
delete pkt; |
848 |
} |
849 |
|
850 |
void |
851 |
connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) |
852 |
{ |
853 |
slog (L_TRACE, "%s << PT_CONNECT_INFO(%s,%s,p%02x)", conf->nodename, |
854 |
vpn->conns[rid - 1]->conf->nodename, (const char *)rsi, |
855 |
conf->protocols); |
856 |
|
857 |
connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); |
858 |
|
859 |
r->hmac_set (octx); |
860 |
send_vpn_packet (r, si); |
861 |
|
862 |
delete r; |
863 |
} |
864 |
|
865 |
inline void |
866 |
connection::establish_connection_cb (ev::timer &w, int revents) |
867 |
{ |
868 |
if (!(ictx && octx) |
869 |
&& conf != THISNODE |
870 |
&& connectmode != conf_node::C_NEVER |
871 |
&& connectmode != conf_node::C_DISABLED |
872 |
&& !w.is_active ()) |
873 |
{ |
874 |
// a bit hacky, if ondemand, and packets are no longer queued, then reset the connection |
875 |
// and stop trying. should probably be handled by a per-connection expire handler. |
876 |
if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ()) |
877 |
{ |
878 |
reset_connection (); |
879 |
return; |
880 |
} |
881 |
|
882 |
last_establish_attempt = ev_now (); |
883 |
|
884 |
ev::tstamp retry_int = ev::tstamp (retry_cnt & 3 |
885 |
? (retry_cnt & 3) + 1 |
886 |
: 1 << (retry_cnt >> 2)); |
887 |
|
888 |
reset_si (); |
889 |
|
890 |
bool slow = si.prot & PROT_SLOW; |
891 |
|
892 |
if (si.prot && !si.host && vpn->can_direct (THISNODE, conf)) |
893 |
{ |
894 |
/*TODO*/ /* start the timer so we don't recurse endlessly */ |
895 |
w.start (1); |
896 |
vpn->send_connect_request (this); |
897 |
} |
898 |
else |
899 |
{ |
900 |
if (si.valid ()) |
901 |
slog (L_DEBUG, _("%s: sending direct connection request to %s."), |
902 |
conf->nodename, (const char *)si); |
903 |
|
904 |
const sockinfo &dsi = forward_si (si); |
905 |
|
906 |
slow = slow || (dsi.prot & PROT_SLOW); |
907 |
|
908 |
if (dsi.valid () && auth_rate_limiter.can (dsi)) |
909 |
{ |
910 |
if (retry_cnt < 4) |
911 |
send_auth_request (dsi, true); |
912 |
else |
913 |
send_ping (dsi, 0); |
914 |
} |
915 |
} |
916 |
|
917 |
retry_int *= slow ? 8. : 0.9; |
918 |
|
919 |
if (retry_int < conf->max_retry) |
920 |
retry_cnt++; |
921 |
else |
922 |
retry_int = conf->max_retry; |
923 |
|
924 |
w.start (retry_int); |
925 |
} |
926 |
} |
927 |
|
928 |
void |
929 |
connection::reset_connection () |
930 |
{ |
931 |
if (ictx && octx) |
932 |
{ |
933 |
slog (L_INFO, _("%s(%s): connection lost"), |
934 |
conf->nodename, (const char *)si); |
935 |
|
936 |
if (::conf.script_node_down) |
937 |
{ |
938 |
run_script_cb *cb = new run_script_cb; |
939 |
cb->set<connection, &connection::script_node_down> (this); |
940 |
run_script_queued (cb, _("node-down command execution failed, continuing.")); |
941 |
} |
942 |
} |
943 |
|
944 |
delete ictx; ictx = 0; |
945 |
delete octx; octx = 0; |
946 |
|
947 |
si.host = 0; |
948 |
|
949 |
have_snd_auth = false; |
950 |
have_rcv_auth = false; |
951 |
auth_expire = 0.; |
952 |
|
953 |
last_activity = 0.; |
954 |
//last_si_change = 0.; |
955 |
retry_cnt = 0; |
956 |
|
957 |
rekey.stop (); |
958 |
keepalive.stop (); |
959 |
establish_connection.stop (); |
960 |
} |
961 |
|
962 |
void |
963 |
connection::shutdown () |
964 |
{ |
965 |
if (ictx && octx) |
966 |
send_reset (si); |
967 |
|
968 |
reset_connection (); |
969 |
} |
970 |
|
971 |
// poor-man's rekeying |
972 |
inline void |
973 |
connection::rekey_cb (ev::timer &w, int revents) |
974 |
{ |
975 |
reset_connection (); |
976 |
establish_connection (); |
977 |
} |
978 |
|
979 |
void |
980 |
connection::send_data_packet (tap_packet *pkt) |
981 |
{ |
982 |
vpndata_packet *p = new vpndata_packet; |
983 |
int tos = 0; |
984 |
|
985 |
// I am not hilarious about peeking into packets, but so be it. |
986 |
if (conf->inherit_tos && pkt->is_ipv4 ()) |
987 |
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
988 |
|
989 |
p->setup (this, conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
990 |
send_vpn_packet (p, si, tos); |
991 |
|
992 |
delete p; |
993 |
|
994 |
if (oseqno > MAX_SEQNO) |
995 |
rekey (); |
996 |
} |
997 |
|
998 |
void |
999 |
connection::post_inject_queue () |
1000 |
{ |
1001 |
// force a connection every now and when when packets are sent (max 1/s) |
1002 |
if (ev_now () - last_establish_attempt >= 0.95) // arbitrary |
1003 |
establish_connection.stop (); |
1004 |
|
1005 |
establish_connection (); |
1006 |
} |
1007 |
|
1008 |
void |
1009 |
connection::inject_data_packet (tap_packet *pkt) |
1010 |
{ |
1011 |
if (ictx && octx) |
1012 |
send_data_packet (pkt); |
1013 |
else |
1014 |
{ |
1015 |
data_queue.put (new tap_packet (*pkt)); |
1016 |
post_inject_queue (); |
1017 |
} |
1018 |
} |
1019 |
|
1020 |
void |
1021 |
connection::inject_vpn_packet (vpn_packet *pkt, int tos) |
1022 |
{ |
1023 |
if (ictx && octx) |
1024 |
send_vpn_packet (pkt, si, tos); |
1025 |
else |
1026 |
{ |
1027 |
vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); |
1028 |
post_inject_queue (); |
1029 |
} |
1030 |
} |
1031 |
|
1032 |
void |
1033 |
connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
1034 |
{ |
1035 |
last_activity = ev_now (); |
1036 |
|
1037 |
slog (L_NOISE, "%s >> received packet type %d from %d to %d.", |
1038 |
conf->nodename, pkt->typ (), pkt->src (), pkt->dst ()); |
1039 |
|
1040 |
if (connectmode == conf_node::C_DISABLED) |
1041 |
return; |
1042 |
|
1043 |
switch (pkt->typ ()) |
1044 |
{ |
1045 |
case vpn_packet::PT_PING: |
1046 |
slog (L_TRACE, "%s >> PT_PING", conf->nodename); |
1047 |
|
1048 |
// we send pings instead of auth packets after some retries, |
1049 |
// so reset the retry counter and establish a connection |
1050 |
// when we receive a ping. |
1051 |
if (!ictx) |
1052 |
{ |
1053 |
if (auth_rate_limiter.can (rsi)) |
1054 |
send_auth_request (rsi, true); |
1055 |
} |
1056 |
else |
1057 |
// we would love to change the socket address here, but ping's aren't |
1058 |
// authenticated, so we best ignore it. |
1059 |
send_ping (rsi, 1); // pong |
1060 |
|
1061 |
break; |
1062 |
|
1063 |
case vpn_packet::PT_PONG: |
1064 |
slog (L_TRACE, "%s >> PT_PONG", conf->nodename); |
1065 |
|
1066 |
// a PONG might mean that the other side doesn't really know |
1067 |
// about our desire for communication. |
1068 |
establish_connection (); |
1069 |
break; |
1070 |
|
1071 |
case vpn_packet::PT_RESET: |
1072 |
{ |
1073 |
reset_connection (); |
1074 |
|
1075 |
config_packet *p = (config_packet *) pkt; |
1076 |
|
1077 |
if (p->chk_config (conf, rsi) && connectmode == conf_node::C_ALWAYS) |
1078 |
establish_connection (); |
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 |
send_auth_request (rsi, false); |
1105 |
|
1106 |
auth_data auth; |
1107 |
|
1108 |
if (!auth_decrypt (::conf.rsa_key, p->encr, auth)) |
1109 |
{ |
1110 |
slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
1111 |
conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
1112 |
} |
1113 |
else |
1114 |
{ |
1115 |
bool chg = !have_rcv_auth || memcmp (&rcv_auth, &auth, sizeof auth); |
1116 |
|
1117 |
rcv_auth = auth; |
1118 |
have_rcv_auth = true; |
1119 |
|
1120 |
send_auth_response (rsi); |
1121 |
|
1122 |
if (chg) |
1123 |
{ |
1124 |
conf->protocols = p->protocols; |
1125 |
features = p->features & config_packet::get_features (); |
1126 |
|
1127 |
connection_established (rsi); |
1128 |
} |
1129 |
} |
1130 |
|
1131 |
break; |
1132 |
} |
1133 |
|
1134 |
send_reset (rsi); |
1135 |
} |
1136 |
|
1137 |
break; |
1138 |
|
1139 |
case vpn_packet::PT_AUTH_RES: |
1140 |
{ |
1141 |
auth_res_packet *p = (auth_res_packet *)pkt; |
1142 |
|
1143 |
slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); |
1144 |
|
1145 |
if (memcmp (&p->response.mac, snd_auth_mac, sizeof (snd_auth_mac))) |
1146 |
{ |
1147 |
slog (L_ERR, _("%s(%s): unrequested or outdated auth response, ignoring."), |
1148 |
conf->nodename, (const char *)rsi); |
1149 |
} |
1150 |
else if (!have_snd_auth) |
1151 |
{ |
1152 |
memcpy (snd_ecdh_b, p->response.ecdh, sizeof (snd_ecdh_b)); |
1153 |
|
1154 |
have_snd_auth = true; |
1155 |
connection_established (rsi); |
1156 |
} |
1157 |
|
1158 |
break; |
1159 |
} |
1160 |
|
1161 |
send_reset (rsi); |
1162 |
break; |
1163 |
|
1164 |
case vpn_packet::PT_DATA_COMPRESSED: |
1165 |
#if !ENABLE_COMPRESSION |
1166 |
send_reset (rsi); |
1167 |
break; |
1168 |
#endif |
1169 |
|
1170 |
case vpn_packet::PT_DATA_UNCOMPRESSED: |
1171 |
|
1172 |
if (ictx && octx) |
1173 |
{ |
1174 |
vpndata_packet *p = (vpndata_packet *)pkt; |
1175 |
|
1176 |
if (!p->hmac_chk (ictx)) |
1177 |
slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" |
1178 |
"could be an attack, or just corruption or a synchronization error."), |
1179 |
conf->nodename, (const char *)rsi); |
1180 |
else |
1181 |
{ |
1182 |
u32 seqno; |
1183 |
tap_packet *d = p->unpack (this, seqno); |
1184 |
int seqclass = iseqno.seqno_classify (seqno); |
1185 |
|
1186 |
if (seqclass == 0) // ok |
1187 |
{ |
1188 |
vpn->tap->send (d); |
1189 |
|
1190 |
if (si != rsi) |
1191 |
{ |
1192 |
// fast re-sync on source address changes, useful especially for tcp/ip |
1193 |
//if (last_si_change < ev_now () + 5.) |
1194 |
// { |
1195 |
slog (L_INFO, _("%s(%s): changing socket address to %s."), |
1196 |
conf->nodename, (const char *)si, (const char *)rsi); |
1197 |
|
1198 |
si = rsi; |
1199 |
|
1200 |
if (::conf.script_node_change) |
1201 |
{ |
1202 |
run_script_cb *cb = new run_script_cb; |
1203 |
cb->set<connection, &connection::script_node_change> (this); |
1204 |
run_script_queued (cb, _("node-change command execution failed, continuing.")); |
1205 |
} |
1206 |
|
1207 |
// } |
1208 |
//else |
1209 |
// slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."), |
1210 |
// conf->nodename, (const char *)si, (const char *)rsi); |
1211 |
} |
1212 |
} |
1213 |
else if (seqclass == 1) // far history |
1214 |
slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). " |
1215 |
"possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1); |
1216 |
else if (seqclass == 2) // in-window duplicate, happens often on wireless |
1217 |
slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). " |
1218 |
"possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1); |
1219 |
else if (seqclass == 3) // reset |
1220 |
{ |
1221 |
slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). " |
1222 |
"probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1); |
1223 |
send_reset (rsi); |
1224 |
} |
1225 |
|
1226 |
delete d; |
1227 |
break; |
1228 |
} |
1229 |
} |
1230 |
|
1231 |
send_reset (rsi); |
1232 |
break; |
1233 |
|
1234 |
case vpn_packet::PT_CONNECT_REQ: |
1235 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1236 |
{ |
1237 |
connect_req_packet *p = (connect_req_packet *)pkt; |
1238 |
|
1239 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1240 |
{ |
1241 |
connection *c = vpn->conns[p->id - 1]; |
1242 |
conf->protocols = p->protocols; |
1243 |
|
1244 |
slog (L_TRACE, "%s >> PT_CONNECT_REQ(%s,p%02x) [%d]", |
1245 |
conf->nodename, vpn->conns[p->id - 1]->conf->nodename, |
1246 |
p->protocols, |
1247 |
c->ictx && c->octx); |
1248 |
|
1249 |
if (c->ictx && c->octx) |
1250 |
{ |
1251 |
// send connect_info packets to both sides, in case one is |
1252 |
// behind a nat firewall (or both ;) |
1253 |
c->send_connect_info (conf->id, si, conf->protocols); |
1254 |
send_connect_info (c->conf->id, c->si, c->conf->protocols); |
1255 |
} |
1256 |
else |
1257 |
c->establish_connection (); |
1258 |
} |
1259 |
else |
1260 |
slog (L_WARN, |
1261 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1262 |
p->id); |
1263 |
} |
1264 |
|
1265 |
break; |
1266 |
|
1267 |
case vpn_packet::PT_CONNECT_INFO: |
1268 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1269 |
{ |
1270 |
connect_info_packet *p = (connect_info_packet *)pkt; |
1271 |
|
1272 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1273 |
{ |
1274 |
connection *c = vpn->conns[p->id - 1]; |
1275 |
|
1276 |
c->conf->protocols = p->protocols; |
1277 |
protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); |
1278 |
p->si.upgrade_protocol (protocol, c->conf); |
1279 |
|
1280 |
slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s,protocols=%02x,protocol=%02x,upgradable=%02x) [%d]", |
1281 |
conf->nodename, |
1282 |
vpn->conns[p->id - 1]->conf->nodename, |
1283 |
(const char *)p->si, |
1284 |
p->protocols, |
1285 |
protocol, |
1286 |
p->si.supported_protocols (c->conf), |
1287 |
!c->ictx && !c->octx); |
1288 |
|
1289 |
const sockinfo &dsi = forward_si (p->si); |
1290 |
|
1291 |
if (dsi.valid ()) |
1292 |
c->send_auth_request (dsi, true); |
1293 |
else |
1294 |
slog (L_INFO, "connect info for %s received (%s), but still unable to contact.", |
1295 |
vpn->conns[p->id - 1]->conf->nodename, |
1296 |
(const char *)p->si); |
1297 |
} |
1298 |
else |
1299 |
slog (L_WARN, |
1300 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1301 |
p->id); |
1302 |
} |
1303 |
|
1304 |
break; |
1305 |
|
1306 |
default: |
1307 |
send_reset (rsi); |
1308 |
break; |
1309 |
} |
1310 |
} |
1311 |
|
1312 |
inline void |
1313 |
connection::keepalive_cb (ev::timer &w, int revents) |
1314 |
{ |
1315 |
ev_tstamp when = last_activity + ::conf.keepalive - ev::now (); |
1316 |
|
1317 |
if (when >= 0) |
1318 |
w.start (when); |
1319 |
else if (when < -15) |
1320 |
{ |
1321 |
reset_connection (); |
1322 |
establish_connection (); |
1323 |
} |
1324 |
else if (conf->connectmode != conf_node::C_ONDEMAND |
1325 |
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
1326 |
{ |
1327 |
w.start (3); |
1328 |
send_ping (si); |
1329 |
} |
1330 |
else if (when >= -10) |
1331 |
// hold ondemand connections implicitly a few seconds longer |
1332 |
// should delete octx, though, or something like that ;) |
1333 |
w.start (when + 10); |
1334 |
else |
1335 |
reset_connection (); |
1336 |
} |
1337 |
|
1338 |
void |
1339 |
connection::send_connect_request (int id) |
1340 |
{ |
1341 |
connect_req_packet *p = new connect_req_packet (conf->id, id, THISNODE->protocols); |
1342 |
|
1343 |
slog (L_TRACE, "%s << PT_CONNECT_REQ(%s,p%02x)", |
1344 |
conf->nodename, vpn->conns[id - 1]->conf->nodename, |
1345 |
THISNODE->protocols); |
1346 |
p->hmac_set (octx); |
1347 |
send_vpn_packet (p, si); |
1348 |
|
1349 |
delete p; |
1350 |
} |
1351 |
|
1352 |
void |
1353 |
connection::script_init_env (const char *ext) |
1354 |
{ |
1355 |
char *env; |
1356 |
asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env); |
1357 |
asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env); |
1358 |
asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext, |
1359 |
0xfe, 0xfd, 0x80, 0x00, conf->id >> 8, |
1360 |
conf->id & 0xff); putenv (env); |
1361 |
} |
1362 |
|
1363 |
void |
1364 |
connection::script_init_connect_env () |
1365 |
{ |
1366 |
vpn->script_init_env (); |
1367 |
|
1368 |
char *env; |
1369 |
asprintf (&env, "DESTID=%d", conf->id); putenv (env); |
1370 |
asprintf (&env, "DESTSI=%s", (const char *)si); putenv (env); |
1371 |
asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); |
1372 |
asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); |
1373 |
asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); |
1374 |
} |
1375 |
|
1376 |
inline const char * |
1377 |
connection::script_node_up () |
1378 |
{ |
1379 |
script_init_connect_env (); |
1380 |
|
1381 |
putenv ((char *)"STATE=up"); |
1382 |
|
1383 |
char *filename; |
1384 |
asprintf (&filename, |
1385 |
"%s/%s", |
1386 |
confbase, |
1387 |
::conf.script_node_up ? ::conf.script_node_up : "node-up"); |
1388 |
|
1389 |
return filename; |
1390 |
} |
1391 |
|
1392 |
inline const char * |
1393 |
connection::script_node_change () |
1394 |
{ |
1395 |
script_init_connect_env (); |
1396 |
|
1397 |
putenv ((char *)"STATE=change"); |
1398 |
|
1399 |
char *filename; |
1400 |
asprintf (&filename, |
1401 |
"%s/%s", |
1402 |
confbase, |
1403 |
::conf.script_node_change ? ::conf.script_node_change : "node-change"); |
1404 |
|
1405 |
return filename; |
1406 |
} |
1407 |
|
1408 |
inline const char * |
1409 |
connection::script_node_down () |
1410 |
{ |
1411 |
script_init_connect_env (); |
1412 |
|
1413 |
putenv ((char *)"STATE=down"); |
1414 |
|
1415 |
char *filename; |
1416 |
asprintf (&filename, |
1417 |
"%s/%s", |
1418 |
confbase, |
1419 |
::conf.script_node_down ? ::conf.script_node_down : "node-down"); |
1420 |
|
1421 |
return filename; |
1422 |
} |
1423 |
|
1424 |
connection::connection (struct vpn *vpn, conf_node *conf) |
1425 |
: vpn(vpn), conf(conf), |
1426 |
#if ENABLE_DNS |
1427 |
dns (0), |
1428 |
#endif |
1429 |
data_queue(conf->max_ttl, conf->max_queue + 1), |
1430 |
vpn_queue(conf->max_ttl, conf->max_queue + 1) |
1431 |
{ |
1432 |
rekey .set<connection, &connection::rekey_cb > (this); |
1433 |
keepalive .set<connection, &connection::keepalive_cb > (this); |
1434 |
establish_connection.set<connection, &connection::establish_connection_cb> (this); |
1435 |
|
1436 |
last_establish_attempt = 0.; |
1437 |
octx = ictx = 0; |
1438 |
|
1439 |
connectmode = conf->connectmode; |
1440 |
|
1441 |
// queue a dummy packet to force an initial connection attempt |
1442 |
if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED) |
1443 |
vpn_queue.put (new net_packet); |
1444 |
|
1445 |
reset_connection (); |
1446 |
} |
1447 |
|
1448 |
connection::~connection () |
1449 |
{ |
1450 |
shutdown (); |
1451 |
} |
1452 |
|
1453 |
void |
1454 |
connection_init () |
1455 |
{ |
1456 |
auth_rate_limiter.clear (); |
1457 |
reset_rate_limiter.clear (); |
1458 |
} |
1459 |
|