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/* |
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connection.C -- manage a single connection |
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Copyright (C) 2003-2008,2010 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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|
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#include "netcompat.h" |
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|
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#if !HAVE_RAND_PSEUDO_BYTES |
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# define RAND_pseudo_bytes RAND_bytes |
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#endif |
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|
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#define MAGIC_OLD "vped\xbd\xc6\xdb\x82" // 8 bytes of magic (still used in the protocol) |
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#define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic (understood but not generated) |
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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 rsachallenge &challenge, 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 rsachallenge &challenge, int enc) |
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{ |
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EVP_CIPHER_CTX_init (&cctx); |
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require (EVP_CipherInit_ex (&cctx, CIPHER, 0, &challenge[CHG_CIPHER_KEY], 0, enc)); |
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HMAC_CTX_init (&hctx); |
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HMAC_Init_ex (&hctx, &challenge[CHG_HMAC_KEY], HMAC_KEYLEN, DIGEST, 0); |
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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 void |
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rsa_hash (const rsaid &id, const rsachallenge &chg, rsaresponse &h) |
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{ |
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EVP_MD_CTX ctx; |
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|
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EVP_MD_CTX_init (&ctx); |
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require (EVP_DigestInit (&ctx, RSA_HASH)); |
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require (EVP_DigestUpdate(&ctx, &chg, sizeof chg)); |
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require (EVP_DigestUpdate(&ctx, &id, sizeof id)); |
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require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0)); |
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EVP_MD_CTX_cleanup (&ctx); |
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} |
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|
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struct rsa_entry |
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{ |
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tstamp expire; |
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rsaid id; |
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rsachallenge chg; |
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}; |
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|
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struct rsa_cache : list<rsa_entry> |
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{ |
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inline void cleaner_cb (ev::timer &w, int revents); ev::timer cleaner; |
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|
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bool find (const rsaid &id, rsachallenge &chg) |
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{ |
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for (iterator i = begin (); i != end (); ++i) |
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{ |
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if (!memcmp (&id, &i->id, sizeof id) && i->expire > ev_now ()) |
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{ |
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memcpy (&chg, &i->chg, sizeof chg); |
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|
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erase (i); |
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return true; |
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} |
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} |
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|
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if (!cleaner.is_active ()) |
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cleaner.again (); |
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|
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return false; |
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} |
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|
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void gen (rsaid &id, rsachallenge &chg) |
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{ |
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rsa_entry e; |
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|
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RAND_bytes ((unsigned char *)&id, sizeof id); |
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RAND_bytes ((unsigned char *)&chg, sizeof chg); |
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|
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e.expire = ev_now () + RSA_TTL; |
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e.id = id; |
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memcpy (&e.chg, &chg, sizeof chg); |
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|
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push_back (e); |
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|
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if (!cleaner.is_active ()) |
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cleaner.again (); |
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} |
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|
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rsa_cache () |
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{ |
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cleaner.set<rsa_cache, &rsa_cache::cleaner_cb> (this); |
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cleaner.set (RSA_TTL, RSA_TTL); |
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} |
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|
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} rsa_cache; |
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|
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void |
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rsa_cache::cleaner_cb (ev::timer &w, int revents) |
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{ |
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if (empty ()) |
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w.stop (); |
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else |
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{ |
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for (iterator i = begin (); i != end (); ) |
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if (i->expire <= ev_now ()) |
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i = erase (i); |
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else |
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++i; |
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} |
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} |
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|
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////////////////////////////////////////////////////////////////////////////// |
215 |
|
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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; |
223 |
|
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expire.set<pkt_queue, &pkt_queue::expire_cb> (this); |
225 |
} |
226 |
|
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pkt_queue::~pkt_queue () |
228 |
{ |
229 |
while (net_packet *p = get ()) |
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delete p; |
231 |
|
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delete [] queue; |
233 |
} |
234 |
|
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void |
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pkt_queue::expire_cb (ev::timer &w, int revents) |
237 |
{ |
238 |
ev_tstamp expire = ev_now () - max_ttl; |
239 |
|
240 |
for (;;) |
241 |
{ |
242 |
if (empty ()) |
243 |
break; |
244 |
|
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double diff = queue[j].tstamp - expire; |
246 |
|
247 |
if (diff >= 0.) |
248 |
{ |
249 |
w.start (diff > 0.5 ? diff : 0.5); |
250 |
break; |
251 |
} |
252 |
|
253 |
delete get (); |
254 |
} |
255 |
} |
256 |
|
257 |
void |
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pkt_queue::put (net_packet *p) |
259 |
{ |
260 |
ev_tstamp now = ev_now (); |
261 |
|
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// start expiry timer |
263 |
if (empty ()) |
264 |
expire.start (max_ttl); |
265 |
|
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int ni = i + 1 == max_queue ? 0 : i + 1; |
267 |
|
268 |
if (ni == j) |
269 |
delete get (); |
270 |
|
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queue[i].pkt = p; |
272 |
queue[i].tstamp = now; |
273 |
|
274 |
i = ni; |
275 |
} |
276 |
|
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net_packet * |
278 |
pkt_queue::get () |
279 |
{ |
280 |
if (empty ()) |
281 |
return 0; |
282 |
|
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net_packet *p = queue[j].pkt; |
284 |
queue[j].pkt = 0; |
285 |
|
286 |
j = j + 1 == max_queue ? 0 : j + 1; |
287 |
|
288 |
return p; |
289 |
} |
290 |
|
291 |
struct net_rateinfo |
292 |
{ |
293 |
u32 host; |
294 |
double pcnt, diff; |
295 |
tstamp last; |
296 |
}; |
297 |
|
298 |
// only do action once every x seconds per host whole allowing bursts. |
299 |
// this implementation ("splay list" ;) is inefficient, |
300 |
// but low on resources. |
301 |
struct net_rate_limiter : list<net_rateinfo> |
302 |
{ |
303 |
# define NRL_ALPHA (1. - 1. / 600.) // allow bursts |
304 |
# define NRL_CUTOFF 10. // one event every CUTOFF seconds |
305 |
# define NRL_EXPIRE (NRL_CUTOFF * 30.) // expire entries after this time |
306 |
# define NRL_MAXDIF (NRL_CUTOFF * (1. / (1. - NRL_ALPHA))) // maximum diff /count value |
307 |
|
308 |
bool can (const sockinfo &si) { return can((u32)si.host); } |
309 |
bool can (u32 host); |
310 |
}; |
311 |
|
312 |
static net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
313 |
|
314 |
bool |
315 |
net_rate_limiter::can (u32 host) |
316 |
{ |
317 |
iterator i; |
318 |
|
319 |
for (i = begin (); i != end (); ) |
320 |
if (i->host == host) |
321 |
break; |
322 |
else if (i->last < ev_now () - NRL_EXPIRE) |
323 |
i = erase (i); |
324 |
else |
325 |
i++; |
326 |
|
327 |
if (i == end ()) |
328 |
{ |
329 |
net_rateinfo ri; |
330 |
|
331 |
ri.host = host; |
332 |
ri.pcnt = 1.; |
333 |
ri.diff = NRL_MAXDIF; |
334 |
ri.last = ev_now (); |
335 |
|
336 |
push_front (ri); |
337 |
|
338 |
return true; |
339 |
} |
340 |
else |
341 |
{ |
342 |
net_rateinfo ri (*i); |
343 |
erase (i); |
344 |
|
345 |
ri.pcnt = ri.pcnt * NRL_ALPHA; |
346 |
ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last); |
347 |
|
348 |
ri.last = ev_now (); |
349 |
|
350 |
double dif = ri.diff / ri.pcnt; |
351 |
|
352 |
bool send = dif > NRL_CUTOFF; |
353 |
|
354 |
if (dif > NRL_MAXDIF) |
355 |
{ |
356 |
ri.pcnt = 1.; |
357 |
ri.diff = NRL_MAXDIF; |
358 |
} |
359 |
else if (send) |
360 |
ri.pcnt++; |
361 |
|
362 |
push_front (ri); |
363 |
|
364 |
return send; |
365 |
} |
366 |
} |
367 |
|
368 |
///////////////////////////////////////////////////////////////////////////// |
369 |
|
370 |
unsigned char hmac_packet::hmac_digest[EVP_MAX_MD_SIZE]; |
371 |
|
372 |
void |
373 |
hmac_packet::hmac_gen (crypto_ctx *ctx) |
374 |
{ |
375 |
unsigned int xlen; |
376 |
|
377 |
HMAC_CTX *hctx = &ctx->hctx; |
378 |
|
379 |
HMAC_Init_ex (hctx, 0, 0, 0, 0); |
380 |
HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), |
381 |
len - sizeof (hmac_packet)); |
382 |
HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen); |
383 |
} |
384 |
|
385 |
void |
386 |
hmac_packet::hmac_set (crypto_ctx *ctx) |
387 |
{ |
388 |
hmac_gen (ctx); |
389 |
|
390 |
memcpy (hmac, hmac_digest, HMACLENGTH); |
391 |
} |
392 |
|
393 |
bool |
394 |
hmac_packet::hmac_chk (crypto_ctx *ctx) |
395 |
{ |
396 |
hmac_gen (ctx); |
397 |
|
398 |
return !memcmp (hmac, hmac_digest, HMACLENGTH); |
399 |
} |
400 |
|
401 |
void |
402 |
vpn_packet::set_hdr (ptype type_, unsigned int dst) |
403 |
{ |
404 |
type = type_; |
405 |
|
406 |
int src = THISNODE->id; |
407 |
|
408 |
src1 = src; |
409 |
srcdst = ((src >> 8) << 4) | (dst >> 8); |
410 |
dst1 = dst; |
411 |
} |
412 |
|
413 |
#define MAXVPNDATA (MAX_MTU - 6 - 6) |
414 |
#define DATAHDR (sizeof (u32) + RAND_SIZE) |
415 |
|
416 |
struct vpndata_packet : vpn_packet |
417 |
{ |
418 |
u8 data[MAXVPNDATA + DATAHDR]; // seqno |
419 |
|
420 |
void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno); |
421 |
tap_packet *unpack (connection *conn, u32 &seqno); |
422 |
|
423 |
private: |
424 |
const u32 data_hdr_size () const |
425 |
{ |
426 |
return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; |
427 |
} |
428 |
}; |
429 |
|
430 |
void |
431 |
vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
432 |
{ |
433 |
EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
434 |
int outl = 0, outl2; |
435 |
ptype type = PT_DATA_UNCOMPRESSED; |
436 |
|
437 |
#if ENABLE_COMPRESSION |
438 |
u8 cdata[MAX_MTU]; |
439 |
|
440 |
if (conn->features & FEATURE_COMPRESSION) |
441 |
{ |
442 |
u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
443 |
|
444 |
if (cl) |
445 |
{ |
446 |
type = PT_DATA_COMPRESSED; |
447 |
d = cdata; |
448 |
l = cl + 2; |
449 |
|
450 |
d[0] = cl >> 8; |
451 |
d[1] = cl; |
452 |
} |
453 |
} |
454 |
#endif |
455 |
|
456 |
require (EVP_EncryptInit_ex (cctx, 0, 0, 0, 0)); |
457 |
|
458 |
struct { |
459 |
#if RAND_SIZE |
460 |
u8 rnd[RAND_SIZE]; |
461 |
#endif |
462 |
u32 seqno; |
463 |
} datahdr; |
464 |
|
465 |
datahdr.seqno = ntohl (seqno); |
466 |
#if RAND_SIZE |
467 |
RAND_pseudo_bytes ((unsigned char *) 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_DecryptInit_ex (cctx, 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 |
/* this overwrites part of the src mac, but we fix that later */ |
511 |
require (EVP_DecryptUpdate (cctx, |
512 |
d, &outl2, |
513 |
(unsigned char *)&data, len - data_hdr_size ())); |
514 |
outl += outl2; |
515 |
|
516 |
require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2)); |
517 |
outl += outl2; |
518 |
|
519 |
seqno = ntohl (*(u32 *)(d + RAND_SIZE)); |
520 |
|
521 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
522 |
id2mac (src (), p->src); |
523 |
|
524 |
#if ENABLE_COMPRESSION |
525 |
if (type == PT_DATA_COMPRESSED) |
526 |
{ |
527 |
u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; |
528 |
|
529 |
p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0, |
530 |
&(*p)[6 + 6], MAX_MTU) |
531 |
+ 6 + 6; |
532 |
} |
533 |
else |
534 |
p->len = outl + (6 + 6 - DATAHDR); |
535 |
#endif |
536 |
|
537 |
return p; |
538 |
} |
539 |
|
540 |
struct ping_packet : vpn_packet |
541 |
{ |
542 |
void setup (int dst, ptype type) |
543 |
{ |
544 |
set_hdr (type, dst); |
545 |
len = sizeof (*this) - sizeof (net_packet); |
546 |
} |
547 |
}; |
548 |
|
549 |
struct config_packet : vpn_packet |
550 |
{ |
551 |
// actually, hmaclen cannot be checked because the hmac |
552 |
// field comes before this data, so peers with other |
553 |
// hmacs simply will not work. |
554 |
u8 prot_major, prot_minor, randsize, hmaclen; |
555 |
u8 flags, challengelen, features, pad3; |
556 |
u32 cipher_nid, digest_nid, hmac_nid; |
557 |
|
558 |
void setup (ptype type, int dst); |
559 |
bool chk_config () const; |
560 |
|
561 |
static u8 get_features () |
562 |
{ |
563 |
u8 f = 0; |
564 |
#if ENABLE_COMPRESSION |
565 |
f |= FEATURE_COMPRESSION; |
566 |
#endif |
567 |
#if ENABLE_ROHC |
568 |
f |= FEATURE_ROHC; |
569 |
#endif |
570 |
#if ENABLE_BRIDGING |
571 |
f |= FEATURE_BRIDGING; |
572 |
#endif |
573 |
return f; |
574 |
} |
575 |
}; |
576 |
|
577 |
void |
578 |
config_packet::setup (ptype type, int dst) |
579 |
{ |
580 |
prot_major = PROTOCOL_MAJOR; |
581 |
prot_minor = PROTOCOL_MINOR; |
582 |
randsize = RAND_SIZE; |
583 |
hmaclen = HMACLENGTH; |
584 |
flags = 0; |
585 |
challengelen = sizeof (rsachallenge); |
586 |
features = get_features (); |
587 |
|
588 |
cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); |
589 |
digest_nid = htonl (EVP_MD_type (RSA_HASH)); |
590 |
hmac_nid = htonl (EVP_MD_type (DIGEST)); |
591 |
|
592 |
len = sizeof (*this) - sizeof (net_packet); |
593 |
set_hdr (type, dst); |
594 |
} |
595 |
|
596 |
bool |
597 |
config_packet::chk_config () const |
598 |
{ |
599 |
if (prot_major != PROTOCOL_MAJOR) |
600 |
slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); |
601 |
else if (randsize != RAND_SIZE) |
602 |
slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE); |
603 |
else if (hmaclen != HMACLENGTH) |
604 |
slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH); |
605 |
else if (challengelen != sizeof (rsachallenge)) |
606 |
slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge)); |
607 |
else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER))) |
608 |
slog (L_WARN, _("cipher mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER)); |
609 |
else if (digest_nid != htonl (EVP_MD_type (RSA_HASH))) |
610 |
slog (L_WARN, _("digest mismatch (remote %x <=> local %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH)); |
611 |
else if (hmac_nid != htonl (EVP_MD_type (DIGEST))) |
612 |
slog (L_WARN, _("hmac mismatch (remote %x <=> local %x)"), ntohl (hmac_nid), EVP_MD_type (DIGEST)); |
613 |
else |
614 |
return true; |
615 |
|
616 |
return false; |
617 |
} |
618 |
|
619 |
struct auth_req_packet : config_packet |
620 |
{ |
621 |
char magic[8]; |
622 |
u8 initiate; // false if this is just an automatic reply |
623 |
u8 protocols; // supported protocols (will be patched on forward) |
624 |
u8 pad2, pad3; |
625 |
rsaid id; |
626 |
rsaencrdata encr; |
627 |
|
628 |
auth_req_packet (int dst, bool initiate_, u8 protocols_) |
629 |
{ |
630 |
config_packet::setup (PT_AUTH_REQ, dst); |
631 |
strncpy (magic, MAGIC_OLD, 8); |
632 |
initiate = !!initiate_; |
633 |
protocols = protocols_; |
634 |
|
635 |
len = sizeof (*this) - sizeof (net_packet); |
636 |
} |
637 |
}; |
638 |
|
639 |
struct auth_res_packet : config_packet |
640 |
{ |
641 |
rsaid id; |
642 |
u8 pad1, pad2, pad3; |
643 |
u8 response_len; // encrypted length |
644 |
rsaresponse response; |
645 |
|
646 |
auth_res_packet (int dst) |
647 |
{ |
648 |
config_packet::setup (PT_AUTH_RES, dst); |
649 |
|
650 |
len = sizeof (*this) - sizeof (net_packet); |
651 |
} |
652 |
}; |
653 |
|
654 |
struct connect_req_packet : vpn_packet |
655 |
{ |
656 |
u8 id, protocols; |
657 |
u8 pad1, pad2; |
658 |
|
659 |
connect_req_packet (int dst, int id_, u8 protocols_) |
660 |
: id(id_) |
661 |
, protocols(protocols_) |
662 |
{ |
663 |
set_hdr (PT_CONNECT_REQ, dst); |
664 |
len = sizeof (*this) - sizeof (net_packet); |
665 |
} |
666 |
}; |
667 |
|
668 |
struct connect_info_packet : vpn_packet |
669 |
{ |
670 |
u8 id, protocols; |
671 |
u8 pad1, pad2; |
672 |
sockinfo si; |
673 |
|
674 |
connect_info_packet (int dst, int id_, const sockinfo &si_, u8 protocols_) |
675 |
: id(id_) |
676 |
, protocols(protocols_) |
677 |
, si(si_) |
678 |
{ |
679 |
set_hdr (PT_CONNECT_INFO, dst); |
680 |
|
681 |
len = sizeof (*this) - sizeof (net_packet); |
682 |
} |
683 |
}; |
684 |
|
685 |
///////////////////////////////////////////////////////////////////////////// |
686 |
|
687 |
void |
688 |
connection::connection_established () |
689 |
{ |
690 |
slog (L_NOISE, _("%s: possible connection establish (ictx %d, octx %d)"), conf->nodename, !!ictx, !!octx); |
691 |
|
692 |
if (ictx && octx) |
693 |
{ |
694 |
// make sure rekeying timeouts are slightly asymmetric |
695 |
ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); |
696 |
rekey.start (rekey_interval, rekey_interval); |
697 |
keepalive.start (::conf.keepalive); |
698 |
|
699 |
// send queued packets |
700 |
if (ictx && octx) |
701 |
{ |
702 |
while (tap_packet *p = (tap_packet *)data_queue.get ()) |
703 |
{ |
704 |
if (p->len) send_data_packet (p); |
705 |
delete p; |
706 |
} |
707 |
|
708 |
while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
709 |
{ |
710 |
if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); |
711 |
delete p; |
712 |
} |
713 |
} |
714 |
|
715 |
vpn->connection_established (this); |
716 |
} |
717 |
else |
718 |
{ |
719 |
retry_cnt = 0; |
720 |
establish_connection.start (5); |
721 |
keepalive.stop (); |
722 |
rekey.stop (); |
723 |
} |
724 |
} |
725 |
|
726 |
void |
727 |
connection::reset_si () |
728 |
{ |
729 |
if (vpn->can_direct (THISNODE, conf)) |
730 |
protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ()); |
731 |
else |
732 |
{ |
733 |
slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename); |
734 |
protocol = 0; |
735 |
} |
736 |
|
737 |
si.set (conf, protocol); |
738 |
|
739 |
is_direct = si.valid (); |
740 |
} |
741 |
|
742 |
// ensure sockinfo is valid, forward if necessary |
743 |
const sockinfo & |
744 |
connection::forward_si (const sockinfo &si) const |
745 |
{ |
746 |
if (!si.valid ()) |
747 |
{ |
748 |
connection *r = vpn->find_router_for (this); |
749 |
|
750 |
if (r) |
751 |
{ |
752 |
slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."), |
753 |
conf->nodename, r->conf->nodename); |
754 |
return r->si; |
755 |
} |
756 |
else |
757 |
slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."), |
758 |
conf->nodename); |
759 |
} |
760 |
|
761 |
return si; |
762 |
} |
763 |
|
764 |
void |
765 |
connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
766 |
{ |
767 |
if (!vpn->send_vpn_packet (pkt, si, tos)) |
768 |
reset_connection (); |
769 |
} |
770 |
|
771 |
void |
772 |
connection::send_ping (const sockinfo &si, u8 pong) |
773 |
{ |
774 |
ping_packet *pkt = new ping_packet; |
775 |
|
776 |
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
777 |
|
778 |
slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); |
779 |
|
780 |
send_vpn_packet (pkt, si, IPTOS_LOWDELAY); |
781 |
|
782 |
delete pkt; |
783 |
} |
784 |
|
785 |
void |
786 |
connection::send_reset (const sockinfo &si) |
787 |
{ |
788 |
if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED) |
789 |
{ |
790 |
config_packet *pkt = new config_packet; |
791 |
|
792 |
pkt->setup (vpn_packet::PT_RESET, conf->id); |
793 |
send_vpn_packet (pkt, si, IPTOS_MINCOST); |
794 |
|
795 |
delete pkt; |
796 |
} |
797 |
} |
798 |
|
799 |
void |
800 |
connection::send_auth_request (const sockinfo &si, bool initiate) |
801 |
{ |
802 |
auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); |
803 |
|
804 |
rsachallenge chg; |
805 |
rsa_cache.gen (pkt->id, chg); |
806 |
rsa_encrypt (conf->rsa_key, chg, pkt->encr); |
807 |
|
808 |
slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); |
809 |
|
810 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly |
811 |
|
812 |
delete pkt; |
813 |
} |
814 |
|
815 |
void |
816 |
connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg) |
817 |
{ |
818 |
auth_res_packet *pkt = new auth_res_packet (conf->id); |
819 |
|
820 |
pkt->id = id; |
821 |
|
822 |
rsa_hash (id, chg, pkt->response); |
823 |
|
824 |
pkt->hmac_set (octx); |
825 |
|
826 |
slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); |
827 |
|
828 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
829 |
|
830 |
delete pkt; |
831 |
} |
832 |
|
833 |
void |
834 |
connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) |
835 |
{ |
836 |
slog (L_TRACE, "%s << PT_CONNECT_INFO(%s,%s)", conf->nodename, |
837 |
vpn->conns[rid - 1]->conf->nodename, (const char *)rsi); |
838 |
|
839 |
connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); |
840 |
|
841 |
r->hmac_set (octx); |
842 |
send_vpn_packet (r, si); |
843 |
|
844 |
delete r; |
845 |
} |
846 |
|
847 |
inline void |
848 |
connection::establish_connection_cb (ev::timer &w, int revents) |
849 |
{ |
850 |
if (!ictx |
851 |
&& conf != THISNODE |
852 |
&& connectmode != conf_node::C_NEVER |
853 |
&& connectmode != conf_node::C_DISABLED |
854 |
&& !w.is_active ()) |
855 |
{ |
856 |
// a bit hacky, if ondemand, and packets are no longer queued, then reset the connection |
857 |
// and stop trying. should probably be handled by a per-connection expire handler. |
858 |
if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ()) |
859 |
{ |
860 |
reset_connection (); |
861 |
return; |
862 |
} |
863 |
|
864 |
last_establish_attempt = ev_now (); |
865 |
|
866 |
ev::tstamp retry_int = ev::tstamp (retry_cnt & 3 |
867 |
? (retry_cnt & 3) + 1 |
868 |
: 1 << (retry_cnt >> 2)); |
869 |
|
870 |
reset_si (); |
871 |
|
872 |
bool slow = si.prot & PROT_SLOW; |
873 |
|
874 |
if (si.prot && !si.host && vpn->can_direct (THISNODE, conf)) |
875 |
{ |
876 |
/*TODO*/ /* start the timer so we don't recurse endlessly */ |
877 |
w.start (1); |
878 |
vpn->send_connect_request (this); |
879 |
} |
880 |
else |
881 |
{ |
882 |
if (si.valid ()) |
883 |
slog (L_DEBUG, _("%s: sending direct connection request to %s."), |
884 |
conf->nodename, (const char *)si); |
885 |
|
886 |
const sockinfo &dsi = forward_si (si); |
887 |
|
888 |
slow = slow || (dsi.prot & PROT_SLOW); |
889 |
|
890 |
if (dsi.valid () && auth_rate_limiter.can (dsi)) |
891 |
{ |
892 |
if (retry_cnt < 4) |
893 |
send_auth_request (dsi, true); |
894 |
else |
895 |
send_ping (dsi, 0); |
896 |
} |
897 |
} |
898 |
|
899 |
retry_int *= slow ? 8. : 0.9; |
900 |
|
901 |
if (retry_int < conf->max_retry) |
902 |
retry_cnt++; |
903 |
else |
904 |
retry_int = conf->max_retry; |
905 |
|
906 |
w.start (retry_int); |
907 |
} |
908 |
} |
909 |
|
910 |
void |
911 |
connection::reset_connection () |
912 |
{ |
913 |
if (ictx && octx) |
914 |
{ |
915 |
slog (L_INFO, _("%s(%s): connection lost"), |
916 |
conf->nodename, (const char *)si); |
917 |
|
918 |
if (::conf.script_node_down) |
919 |
{ |
920 |
run_script_cb *cb = new run_script_cb; |
921 |
cb->set<connection, &connection::script_node_down> (this); |
922 |
run_script_queued (cb, _("node-down command execution failed, continuing.")); |
923 |
} |
924 |
} |
925 |
|
926 |
delete ictx; ictx = 0; |
927 |
delete octx; octx = 0; |
928 |
#if ENABLE_DNS |
929 |
dnsv4_reset_connection (); |
930 |
#endif |
931 |
|
932 |
si.host = 0; |
933 |
|
934 |
last_activity = 0.; |
935 |
//last_si_change = 0.; |
936 |
retry_cnt = 0; |
937 |
|
938 |
rekey.stop (); |
939 |
keepalive.stop (); |
940 |
establish_connection.stop (); |
941 |
} |
942 |
|
943 |
void |
944 |
connection::shutdown () |
945 |
{ |
946 |
if (ictx && octx) |
947 |
send_reset (si); |
948 |
|
949 |
reset_connection (); |
950 |
} |
951 |
|
952 |
// poor-man's rekeying |
953 |
inline void |
954 |
connection::rekey_cb (ev::timer &w, int revents) |
955 |
{ |
956 |
reset_connection (); |
957 |
establish_connection (); |
958 |
} |
959 |
|
960 |
void |
961 |
connection::send_data_packet (tap_packet *pkt) |
962 |
{ |
963 |
vpndata_packet *p = new vpndata_packet; |
964 |
int tos = 0; |
965 |
|
966 |
// I am not hilarious about peeking into packets, but so be it. |
967 |
if (conf->inherit_tos && pkt->is_ipv4 ()) |
968 |
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
969 |
|
970 |
p->setup (this, conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
971 |
send_vpn_packet (p, si, tos); |
972 |
|
973 |
delete p; |
974 |
|
975 |
if (oseqno > MAX_SEQNO) |
976 |
rekey (); |
977 |
} |
978 |
|
979 |
void |
980 |
connection::post_inject_queue () |
981 |
{ |
982 |
// force a connection every now and when when packets are sent (max 1/s) |
983 |
if (ev_now () - last_establish_attempt >= 0.95) // arbitrary |
984 |
establish_connection.stop (); |
985 |
|
986 |
establish_connection (); |
987 |
} |
988 |
|
989 |
void |
990 |
connection::inject_data_packet (tap_packet *pkt) |
991 |
{ |
992 |
if (ictx && octx) |
993 |
send_data_packet (pkt); |
994 |
else |
995 |
{ |
996 |
data_queue.put (new tap_packet (*pkt)); |
997 |
post_inject_queue (); |
998 |
} |
999 |
} |
1000 |
|
1001 |
void |
1002 |
connection::inject_vpn_packet (vpn_packet *pkt, int tos) |
1003 |
{ |
1004 |
if (ictx && octx) |
1005 |
send_vpn_packet (pkt, si, tos); |
1006 |
else |
1007 |
{ |
1008 |
vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); |
1009 |
post_inject_queue (); |
1010 |
} |
1011 |
} |
1012 |
|
1013 |
void |
1014 |
connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
1015 |
{ |
1016 |
last_activity = ev_now (); |
1017 |
|
1018 |
slog (L_NOISE, "%s >> received packet type %d from %d to %d.", |
1019 |
conf->nodename, pkt->typ (), pkt->src (), pkt->dst ()); |
1020 |
|
1021 |
if (connectmode == conf_node::C_DISABLED) |
1022 |
return; |
1023 |
|
1024 |
switch (pkt->typ ()) |
1025 |
{ |
1026 |
case vpn_packet::PT_PING: |
1027 |
slog (L_TRACE, "%s >> PT_PING", conf->nodename); |
1028 |
|
1029 |
// we send pings instead of auth packets after some retries, |
1030 |
// so reset the retry counter and establish a connection |
1031 |
// when we receive a ping. |
1032 |
if (!ictx) |
1033 |
{ |
1034 |
if (auth_rate_limiter.can (rsi)) |
1035 |
send_auth_request (rsi, true); |
1036 |
} |
1037 |
else |
1038 |
// we would love to change the socket address here, but ping's aren't |
1039 |
// authenticated, so we best ignore it. |
1040 |
send_ping (rsi, 1); // pong |
1041 |
|
1042 |
break; |
1043 |
|
1044 |
case vpn_packet::PT_PONG: |
1045 |
slog (L_TRACE, "%s >> PT_PONG", conf->nodename); |
1046 |
|
1047 |
// a PONG might mean that the other side doesn't really know |
1048 |
// about our desire for communication. |
1049 |
establish_connection (); |
1050 |
break; |
1051 |
|
1052 |
case vpn_packet::PT_RESET: |
1053 |
{ |
1054 |
reset_connection (); |
1055 |
|
1056 |
config_packet *p = (config_packet *) pkt; |
1057 |
|
1058 |
if (!p->chk_config ()) |
1059 |
{ |
1060 |
slog (L_WARN, _("%s(%s): protocol mismatch, disabling node."), |
1061 |
conf->nodename, (const char *)rsi); |
1062 |
connectmode = conf_node::C_DISABLED; |
1063 |
} |
1064 |
else if (connectmode == conf_node::C_ALWAYS) |
1065 |
establish_connection (); |
1066 |
} |
1067 |
break; |
1068 |
|
1069 |
case vpn_packet::PT_AUTH_REQ: |
1070 |
if (auth_rate_limiter.can (rsi)) |
1071 |
{ |
1072 |
auth_req_packet *p = (auth_req_packet *) pkt; |
1073 |
|
1074 |
slog (L_TRACE, "%s >> PT_AUTH_REQ(%s)", conf->nodename, p->initiate ? "initiate" : "reply"); |
1075 |
|
1076 |
if (p->chk_config () |
1077 |
&& (!strncmp (p->magic, MAGIC_OLD, 8) || !strncmp (p->magic, MAGIC, 8))) |
1078 |
{ |
1079 |
if (p->prot_minor != PROTOCOL_MINOR) |
1080 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1081 |
conf->nodename, (const char *)rsi, |
1082 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1083 |
|
1084 |
if (p->initiate) |
1085 |
send_auth_request (rsi, false); |
1086 |
|
1087 |
rsachallenge k; |
1088 |
|
1089 |
if (!rsa_decrypt (::conf.rsa_key, p->encr, k)) |
1090 |
{ |
1091 |
slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
1092 |
conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
1093 |
break; |
1094 |
} |
1095 |
else |
1096 |
{ |
1097 |
delete octx; |
1098 |
|
1099 |
octx = new crypto_ctx (k, 1); |
1100 |
oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; |
1101 |
|
1102 |
conf->protocols = p->protocols; |
1103 |
features = p->features & config_packet::get_features (); |
1104 |
|
1105 |
send_auth_response (rsi, p->id, k); |
1106 |
|
1107 |
connection_established (); |
1108 |
|
1109 |
break; |
1110 |
} |
1111 |
} |
1112 |
else |
1113 |
slog (L_WARN, _("%s(%s): protocol mismatch."), |
1114 |
conf->nodename, (const char *)rsi); |
1115 |
|
1116 |
send_reset (rsi); |
1117 |
} |
1118 |
|
1119 |
break; |
1120 |
|
1121 |
case vpn_packet::PT_AUTH_RES: |
1122 |
{ |
1123 |
auth_res_packet *p = (auth_res_packet *)pkt; |
1124 |
|
1125 |
slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); |
1126 |
|
1127 |
if (p->chk_config ()) |
1128 |
{ |
1129 |
if (p->prot_minor != PROTOCOL_MINOR) |
1130 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1131 |
conf->nodename, (const char *)rsi, |
1132 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1133 |
|
1134 |
rsachallenge chg; |
1135 |
|
1136 |
if (!rsa_cache.find (p->id, chg)) |
1137 |
{ |
1138 |
slog (L_ERR, _("%s(%s): unrequested auth response, ignoring."), |
1139 |
conf->nodename, (const char *)rsi); |
1140 |
break; |
1141 |
} |
1142 |
else |
1143 |
{ |
1144 |
crypto_ctx *cctx = new crypto_ctx (chg, 0); |
1145 |
|
1146 |
if (!p->hmac_chk (cctx)) |
1147 |
{ |
1148 |
slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" |
1149 |
"could be an attack, or just corruption or a synchronization error."), |
1150 |
conf->nodename, (const char *)rsi); |
1151 |
break; |
1152 |
} |
1153 |
else |
1154 |
{ |
1155 |
rsaresponse h; |
1156 |
|
1157 |
rsa_hash (p->id, chg, h); |
1158 |
|
1159 |
if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) |
1160 |
{ |
1161 |
prot_minor = p->prot_minor; |
1162 |
|
1163 |
delete ictx; ictx = cctx; |
1164 |
|
1165 |
iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid |
1166 |
|
1167 |
si = rsi; |
1168 |
protocol = rsi.prot; |
1169 |
|
1170 |
slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), |
1171 |
conf->nodename, (const char *)rsi, |
1172 |
is_direct ? "direct" : "forwarded", |
1173 |
p->prot_major, p->prot_minor); |
1174 |
|
1175 |
connection_established (); |
1176 |
|
1177 |
if (::conf.script_node_up) |
1178 |
{ |
1179 |
run_script_cb *cb = new run_script_cb; |
1180 |
cb->set<connection, &connection::script_node_up> (this); |
1181 |
run_script_queued (cb, _("node-up command execution failed, continuing.")); |
1182 |
} |
1183 |
|
1184 |
break; |
1185 |
} |
1186 |
else |
1187 |
slog (L_ERR, _("%s(%s): sent and received challenge do not match."), |
1188 |
conf->nodename, (const char *)rsi); |
1189 |
} |
1190 |
|
1191 |
delete cctx; |
1192 |
} |
1193 |
} |
1194 |
} |
1195 |
|
1196 |
send_reset (rsi); |
1197 |
break; |
1198 |
|
1199 |
case vpn_packet::PT_DATA_COMPRESSED: |
1200 |
#if !ENABLE_COMPRESSION |
1201 |
send_reset (rsi); |
1202 |
break; |
1203 |
#endif |
1204 |
|
1205 |
case vpn_packet::PT_DATA_UNCOMPRESSED: |
1206 |
|
1207 |
if (ictx && octx) |
1208 |
{ |
1209 |
vpndata_packet *p = (vpndata_packet *)pkt; |
1210 |
|
1211 |
if (!p->hmac_chk (ictx)) |
1212 |
slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" |
1213 |
"could be an attack, or just corruption or a synchronization error."), |
1214 |
conf->nodename, (const char *)rsi); |
1215 |
else |
1216 |
{ |
1217 |
u32 seqno; |
1218 |
tap_packet *d = p->unpack (this, seqno); |
1219 |
int seqclass = iseqno.seqno_classify (seqno); |
1220 |
|
1221 |
if (seqclass == 0) // ok |
1222 |
{ |
1223 |
vpn->tap->send (d); |
1224 |
|
1225 |
if (si != rsi) |
1226 |
{ |
1227 |
// fast re-sync on source address changes, useful especially for tcp/ip |
1228 |
//if (last_si_change < ev_now () + 5.) |
1229 |
// { |
1230 |
slog (L_INFO, _("%s(%s): changing socket address to %s."), |
1231 |
conf->nodename, (const char *)si, (const char *)rsi); |
1232 |
|
1233 |
si = rsi; |
1234 |
|
1235 |
if (::conf.script_node_change) |
1236 |
{ |
1237 |
run_script_cb *cb = new run_script_cb; |
1238 |
cb->set<connection, &connection::script_node_change> (this); |
1239 |
run_script_queued (cb, _("node-change command execution failed, continuing.")); |
1240 |
} |
1241 |
|
1242 |
// } |
1243 |
//else |
1244 |
// slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."), |
1245 |
// conf->nodename, (const char *)si, (const char *)rsi); |
1246 |
} |
1247 |
} |
1248 |
else if (seqclass == 1) // far history |
1249 |
slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). " |
1250 |
"possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1); |
1251 |
else if (seqclass == 2) // in-window duplicate, happens often on wireless |
1252 |
slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). " |
1253 |
"possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1); |
1254 |
else if (seqclass == 3) // reset |
1255 |
{ |
1256 |
slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). " |
1257 |
"probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1); |
1258 |
send_reset (rsi); |
1259 |
} |
1260 |
|
1261 |
delete d; |
1262 |
break; |
1263 |
} |
1264 |
} |
1265 |
|
1266 |
send_reset (rsi); |
1267 |
break; |
1268 |
|
1269 |
case vpn_packet::PT_CONNECT_REQ: |
1270 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1271 |
{ |
1272 |
connect_req_packet *p = (connect_req_packet *)pkt; |
1273 |
|
1274 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1275 |
{ |
1276 |
connection *c = vpn->conns[p->id - 1]; |
1277 |
conf->protocols = p->protocols; |
1278 |
|
1279 |
slog (L_TRACE, "%s >> PT_CONNECT_REQ(%s) [%d]", |
1280 |
conf->nodename, vpn->conns[p->id - 1]->conf->nodename, c->ictx && c->octx); |
1281 |
|
1282 |
if (c->ictx && c->octx) |
1283 |
{ |
1284 |
// send connect_info packets to both sides, in case one is |
1285 |
// behind a nat firewall (or both ;) |
1286 |
c->send_connect_info (conf->id, si, conf->protocols); |
1287 |
send_connect_info (c->conf->id, c->si, c->conf->protocols); |
1288 |
} |
1289 |
else |
1290 |
c->establish_connection (); |
1291 |
} |
1292 |
else |
1293 |
slog (L_WARN, |
1294 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1295 |
p->id); |
1296 |
} |
1297 |
|
1298 |
break; |
1299 |
|
1300 |
case vpn_packet::PT_CONNECT_INFO: |
1301 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1302 |
{ |
1303 |
connect_info_packet *p = (connect_info_packet *)pkt; |
1304 |
|
1305 |
if (p->id > 0 && p->id <= vpn->conns.size ()) |
1306 |
{ |
1307 |
connection *c = vpn->conns[p->id - 1]; |
1308 |
|
1309 |
c->conf->protocols = p->protocols; |
1310 |
protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); |
1311 |
p->si.upgrade_protocol (protocol, c->conf); |
1312 |
|
1313 |
slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s) [%d]", |
1314 |
conf->nodename, vpn->conns[p->id - 1]->conf->nodename, |
1315 |
(const char *)p->si, !c->ictx && !c->octx); |
1316 |
|
1317 |
const sockinfo &dsi = forward_si (p->si); |
1318 |
|
1319 |
if (dsi.valid ()) |
1320 |
c->send_auth_request (dsi, true); |
1321 |
} |
1322 |
else |
1323 |
slog (L_WARN, |
1324 |
_("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1325 |
p->id); |
1326 |
} |
1327 |
|
1328 |
break; |
1329 |
|
1330 |
default: |
1331 |
send_reset (rsi); |
1332 |
break; |
1333 |
} |
1334 |
} |
1335 |
|
1336 |
inline void |
1337 |
connection::keepalive_cb (ev::timer &w, int revents) |
1338 |
{ |
1339 |
if (ev_now () >= last_activity + ::conf.keepalive + 15) |
1340 |
{ |
1341 |
reset_connection (); |
1342 |
establish_connection (); |
1343 |
} |
1344 |
else if (ev_now () < last_activity + ::conf.keepalive) |
1345 |
w.start (last_activity + ::conf.keepalive - ev::now ()); |
1346 |
else if (conf->connectmode != conf_node::C_ONDEMAND |
1347 |
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
1348 |
{ |
1349 |
send_ping (si); |
1350 |
w.start (3); |
1351 |
} |
1352 |
else if (ev_now () < last_activity + ::conf.keepalive + 10) |
1353 |
// hold ondemand connections implicitly a few seconds longer |
1354 |
// should delete octx, though, or something like that ;) |
1355 |
w.start (last_activity + ::conf.keepalive + 10 - ev::now ()); |
1356 |
else |
1357 |
reset_connection (); |
1358 |
} |
1359 |
|
1360 |
void |
1361 |
connection::send_connect_request (int id) |
1362 |
{ |
1363 |
connect_req_packet *p = new connect_req_packet (conf->id, id, conf->protocols); |
1364 |
|
1365 |
slog (L_TRACE, "%s << PT_CONNECT_REQ(%s)", |
1366 |
conf->nodename, vpn->conns[id - 1]->conf->nodename); |
1367 |
p->hmac_set (octx); |
1368 |
send_vpn_packet (p, si); |
1369 |
|
1370 |
delete p; |
1371 |
} |
1372 |
|
1373 |
void |
1374 |
connection::script_init_env (const char *ext) |
1375 |
{ |
1376 |
char *env; |
1377 |
asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env); |
1378 |
asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env); |
1379 |
asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext, |
1380 |
0xfe, 0xfd, 0x80, 0x00, conf->id >> 8, |
1381 |
conf->id & 0xff); putenv (env); |
1382 |
} |
1383 |
|
1384 |
void |
1385 |
connection::script_init_connect_env () |
1386 |
{ |
1387 |
vpn->script_init_env (); |
1388 |
|
1389 |
char *env; |
1390 |
asprintf (&env, "DESTID=%d", conf->id); putenv (env); |
1391 |
asprintf (&env, "DESTSI=%s", (const char *)si); putenv (env); |
1392 |
asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); |
1393 |
asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); |
1394 |
asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); |
1395 |
} |
1396 |
|
1397 |
inline const char * |
1398 |
connection::script_node_up () |
1399 |
{ |
1400 |
script_init_connect_env (); |
1401 |
|
1402 |
putenv ((char *)"STATE=up"); |
1403 |
|
1404 |
char *filename; |
1405 |
asprintf (&filename, |
1406 |
"%s/%s", |
1407 |
confbase, |
1408 |
::conf.script_node_up ? ::conf.script_node_up : "node-up"); |
1409 |
|
1410 |
return filename; |
1411 |
} |
1412 |
|
1413 |
inline const char * |
1414 |
connection::script_node_change () |
1415 |
{ |
1416 |
script_init_connect_env (); |
1417 |
|
1418 |
putenv ((char *)"STATE=change"); |
1419 |
|
1420 |
char *filename; |
1421 |
asprintf (&filename, |
1422 |
"%s/%s", |
1423 |
confbase, |
1424 |
::conf.script_node_change ? ::conf.script_node_change : "node-change"); |
1425 |
|
1426 |
return filename; |
1427 |
} |
1428 |
|
1429 |
inline const char * |
1430 |
connection::script_node_down () |
1431 |
{ |
1432 |
script_init_connect_env (); |
1433 |
|
1434 |
putenv ((char *)"STATE=down"); |
1435 |
|
1436 |
char *filename; |
1437 |
asprintf (&filename, |
1438 |
"%s/%s", |
1439 |
confbase, |
1440 |
::conf.script_node_down ? ::conf.script_node_down : "node-down"); |
1441 |
|
1442 |
return filename; |
1443 |
} |
1444 |
|
1445 |
connection::connection (struct vpn *vpn, conf_node *conf) |
1446 |
: vpn(vpn), conf(conf), |
1447 |
#if ENABLE_DNS |
1448 |
dns (0), |
1449 |
#endif |
1450 |
data_queue(conf->max_ttl, conf->max_queue + 1), |
1451 |
vpn_queue(conf->max_ttl, conf->max_queue + 1) |
1452 |
{ |
1453 |
rekey .set<connection, &connection::rekey_cb > (this); |
1454 |
keepalive .set<connection, &connection::keepalive_cb > (this); |
1455 |
establish_connection.set<connection, &connection::establish_connection_cb> (this); |
1456 |
|
1457 |
last_establish_attempt = 0.; |
1458 |
octx = ictx = 0; |
1459 |
|
1460 |
if (!conf->protocols) // make sure some protocol is enabled |
1461 |
conf->protocols = PROT_UDPv4; |
1462 |
|
1463 |
connectmode = conf->connectmode; |
1464 |
|
1465 |
// queue a dummy packet to force an initial connection attempt |
1466 |
if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED) |
1467 |
vpn_queue.put (new net_packet); |
1468 |
|
1469 |
reset_connection (); |
1470 |
} |
1471 |
|
1472 |
connection::~connection () |
1473 |
{ |
1474 |
shutdown (); |
1475 |
} |
1476 |
|
1477 |
void |
1478 |
connection_init () |
1479 |
{ |
1480 |
auth_rate_limiter.clear (); |
1481 |
reset_rate_limiter.clear (); |
1482 |
} |
1483 |
|