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/* |
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protocol.C -- handle the protocol, encryption, handshaking etc. |
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|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
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(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General 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 |
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along with this program; if not, write to the Free Software |
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Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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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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|
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#include <cstdlib> |
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#include <cstring> |
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#include <cstdio> |
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|
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <sys/poll.h> |
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#include <sys/wait.h> |
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#include <netinet/in.h> |
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#include <arpa/inet.h> |
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#include <errno.h> |
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#include <time.h> |
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#include <unistd.h> |
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|
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#include <openssl/rand.h> |
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#include <openssl/hmac.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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extern "C" { |
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# include "lzf/lzf.h" |
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} |
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|
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#include "gettext.h" |
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#include "pidfile.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 "protocol.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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static time_t next_timecheck; |
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|
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#define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic |
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|
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static u8 |
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best_protocol (u8 protset) |
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{ |
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if (protset & PROT_IPv4) |
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return PROT_IPv4; |
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|
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return PROT_UDPv4; |
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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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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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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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EVP_DigestInit (&ctx, RSA_HASH); |
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EVP_DigestUpdate(&ctx, &chg, sizeof chg); |
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EVP_DigestUpdate(&ctx, &id, sizeof id); |
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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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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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void cleaner_cb (tstamp &ts); time_watcher 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 > 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.at < NOW) |
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cleaner.start (NOW + RSA_TTL); |
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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 = 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.at < NOW) |
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cleaner.start (NOW + RSA_TTL); |
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} |
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|
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rsa_cache () |
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: cleaner (this, &rsa_cache::cleaner_cb) |
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{ } |
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|
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} rsa_cache; |
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|
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void rsa_cache::cleaner_cb (tstamp &ts) |
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{ |
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if (empty ()) |
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ts = TSTAMP_CANCEL; |
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else |
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{ |
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ts = NOW + RSA_TTL; |
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|
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for (iterator i = begin (); i != end (); ) |
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if (i->expire <= 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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typedef callback<const char *, int> run_script_cb; |
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|
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// run a shell script (or actually an external program). |
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static void |
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run_script (const run_script_cb &cb, bool wait) |
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{ |
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int pid; |
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|
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if ((pid = fork ()) == 0) |
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{ |
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char *filename; |
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asprintf (&filename, "%s/%s", confbase, cb(0)); |
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execl (filename, filename, (char *) 0); |
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exit (255); |
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} |
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else if (pid > 0) |
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{ |
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if (wait) |
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{ |
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waitpid (pid, 0, 0); |
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/* TODO: check status */ |
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} |
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} |
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} |
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|
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////////////////////////////////////////////////////////////////////////////// |
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|
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void pkt_queue::put (tap_packet *p) |
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{ |
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if (queue[i]) |
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{ |
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delete queue[i]; |
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j = (j + 1) % QUEUEDEPTH; |
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} |
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|
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queue[i] = p; |
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|
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i = (i + 1) % QUEUEDEPTH; |
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} |
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|
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tap_packet *pkt_queue::get () |
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{ |
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tap_packet *p = queue[j]; |
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|
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if (p) |
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{ |
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queue[j] = 0; |
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j = (j + 1) % QUEUEDEPTH; |
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} |
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|
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return p; |
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} |
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|
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pkt_queue::pkt_queue () |
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{ |
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memset (queue, 0, sizeof (queue)); |
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i = 0; |
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j = 0; |
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} |
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|
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pkt_queue::~pkt_queue () |
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{ |
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for (i = QUEUEDEPTH; --i > 0; ) |
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delete queue[i]; |
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} |
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|
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struct net_rateinfo { |
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u32 host; |
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double pcnt, diff; |
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tstamp last; |
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}; |
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|
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// only do action once every x seconds per host whole allowing bursts. |
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// this implementation ("splay list" ;) is inefficient, |
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// but low on resources. |
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struct net_rate_limiter : list<net_rateinfo> |
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{ |
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static const double ALPHA = 1. - 1. / 90.; // allow bursts |
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static const double CUTOFF = 20.; // one event every CUTOFF seconds |
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static const double EXPIRE = CUTOFF * 30.; // expire entries after this time |
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|
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bool can (const sockinfo &si) { return can((u32)si.host); } |
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bool can (u32 host); |
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}; |
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|
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net_rate_limiter auth_rate_limiter, reset_rate_limiter; |
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|
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bool net_rate_limiter::can (u32 host) |
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{ |
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iterator i; |
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|
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for (i = begin (); i != end (); ) |
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if (i->host == host) |
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break; |
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else if (i->last < NOW - EXPIRE) |
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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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if (i == end ()) |
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{ |
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net_rateinfo ri; |
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|
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ri.host = host; |
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ri.pcnt = 1.; |
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ri.diff = CUTOFF * (1. / (1. - ALPHA)); |
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ri.last = NOW; |
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|
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push_front (ri); |
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|
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return true; |
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} |
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else |
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{ |
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net_rateinfo ri (*i); |
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erase (i); |
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|
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ri.pcnt = ri.pcnt * ALPHA; |
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ri.diff = ri.diff * ALPHA + (NOW - ri.last); |
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|
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ri.last = NOW; |
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|
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bool send = ri.diff / ri.pcnt > CUTOFF; |
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|
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if (send) |
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ri.pcnt++; |
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|
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push_front (ri); |
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|
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return send; |
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} |
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} |
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|
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///////////////////////////////////////////////////////////////////////////// |
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|
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static void next_wakeup (time_t next) |
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{ |
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if (next_timecheck > next) |
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next_timecheck = next; |
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} |
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|
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static unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
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|
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struct hmac_packet:net_packet |
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{ |
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u8 hmac[HMACLENGTH]; // each and every packet has a hmac field, but that is not (yet) checked everywhere |
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|
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void hmac_set (crypto_ctx * ctx); |
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bool hmac_chk (crypto_ctx * ctx); |
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|
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private: |
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void hmac_gen (crypto_ctx * ctx) |
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{ |
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unsigned int xlen; |
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HMAC_CTX *hctx = &ctx->hctx; |
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|
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HMAC_Init_ex (hctx, 0, 0, 0, 0); |
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HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), |
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len - sizeof (hmac_packet)); |
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HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen); |
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} |
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}; |
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|
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void |
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hmac_packet::hmac_set (crypto_ctx * ctx) |
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{ |
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hmac_gen (ctx); |
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|
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memcpy (hmac, hmac_digest, HMACLENGTH); |
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} |
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|
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bool |
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hmac_packet::hmac_chk (crypto_ctx * ctx) |
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{ |
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hmac_gen (ctx); |
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|
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return !memcmp (hmac, hmac_digest, HMACLENGTH); |
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} |
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|
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struct vpn_packet : hmac_packet |
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{ |
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enum ptype |
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{ |
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PT_RESET = 0, |
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PT_DATA_UNCOMPRESSED, |
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PT_DATA_COMPRESSED, |
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PT_PING, PT_PONG, // wasting namespace space? ;) |
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PT_AUTH_REQ, // authentification request |
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PT_AUTH_RES, // authentification response |
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PT_CONNECT_REQ, // want other host to contact me |
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PT_CONNECT_INFO, // request connection to some node |
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PT_MAX |
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}; |
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|
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u8 type; |
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u8 srcdst, src1, dst1; |
372 |
|
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void set_hdr (ptype type, unsigned int dst); |
374 |
|
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unsigned int src () const |
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{ |
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return src1 | ((srcdst >> 4) << 8); |
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} |
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|
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unsigned int dst () const |
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{ |
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return dst1 | ((srcdst & 0xf) << 8); |
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} |
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|
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ptype typ () const |
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{ |
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return (ptype) type; |
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} |
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}; |
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|
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void vpn_packet::set_hdr (ptype type, unsigned int dst) |
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{ |
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this->type = type; |
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|
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int src = THISNODE->id; |
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|
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src1 = src; |
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srcdst = ((src >> 8) << 4) | (dst >> 8); |
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dst1 = dst; |
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} |
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|
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#define MAXVPNDATA (MAX_MTU - 6 - 6) |
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#define DATAHDR (sizeof (u32) + RAND_SIZE) |
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|
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struct vpndata_packet:vpn_packet |
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{ |
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u8 data[MAXVPNDATA + DATAHDR]; // seqno |
408 |
|
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void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno); |
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tap_packet *unpack (connection *conn, u32 &seqno); |
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private: |
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|
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const u32 data_hdr_size () const |
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{ |
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return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; |
416 |
} |
417 |
}; |
418 |
|
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void |
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vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
421 |
{ |
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EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
423 |
int outl = 0, outl2; |
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ptype type = PT_DATA_UNCOMPRESSED; |
425 |
|
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#if ENABLE_COMPRESSION |
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u8 cdata[MAX_MTU]; |
428 |
u32 cl; |
429 |
|
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cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
431 |
if (cl) |
432 |
{ |
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type = PT_DATA_COMPRESSED; |
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d = cdata; |
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l = cl + 2; |
436 |
|
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d[0] = cl >> 8; |
438 |
d[1] = cl; |
439 |
} |
440 |
#endif |
441 |
|
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EVP_EncryptInit_ex (cctx, 0, 0, 0, 0); |
443 |
|
444 |
struct { |
445 |
#if RAND_SIZE |
446 |
u8 rnd[RAND_SIZE]; |
447 |
#endif |
448 |
u32 seqno; |
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} datahdr; |
450 |
|
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datahdr.seqno = ntohl (seqno); |
452 |
#if RAND_SIZE |
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RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE); |
454 |
#endif |
455 |
|
456 |
EVP_EncryptUpdate (cctx, |
457 |
(unsigned char *) data + outl, &outl2, |
458 |
(unsigned char *) &datahdr, DATAHDR); |
459 |
outl += outl2; |
460 |
|
461 |
EVP_EncryptUpdate (cctx, |
462 |
(unsigned char *) data + outl, &outl2, |
463 |
(unsigned char *) d, l); |
464 |
outl += outl2; |
465 |
|
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EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2); |
467 |
outl += outl2; |
468 |
|
469 |
len = outl + data_hdr_size (); |
470 |
|
471 |
set_hdr (type, dst); |
472 |
|
473 |
hmac_set (conn->octx); |
474 |
} |
475 |
|
476 |
tap_packet * |
477 |
vpndata_packet::unpack (connection *conn, u32 &seqno) |
478 |
{ |
479 |
EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; |
480 |
int outl = 0, outl2; |
481 |
tap_packet *p = new tap_packet; |
482 |
u8 *d; |
483 |
u32 l = len - data_hdr_size (); |
484 |
|
485 |
EVP_DecryptInit_ex (cctx, 0, 0, 0, 0); |
486 |
|
487 |
#if ENABLE_COMPRESSION |
488 |
u8 cdata[MAX_MTU]; |
489 |
|
490 |
if (type == PT_DATA_COMPRESSED) |
491 |
d = cdata; |
492 |
else |
493 |
#endif |
494 |
d = &(*p)[6 + 6 - DATAHDR]; |
495 |
|
496 |
/* this overwrites part of the src mac, but we fix that later */ |
497 |
EVP_DecryptUpdate (cctx, |
498 |
d, &outl2, |
499 |
(unsigned char *)&data, len - data_hdr_size ()); |
500 |
outl += outl2; |
501 |
|
502 |
EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2); |
503 |
outl += outl2; |
504 |
|
505 |
seqno = ntohl (*(u32 *)(d + RAND_SIZE)); |
506 |
|
507 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
508 |
id2mac (src (), p->src); |
509 |
|
510 |
#if ENABLE_COMPRESSION |
511 |
if (type == PT_DATA_COMPRESSED) |
512 |
{ |
513 |
u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; |
514 |
|
515 |
p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0, |
516 |
&(*p)[6 + 6], MAX_MTU) |
517 |
+ 6 + 6; |
518 |
} |
519 |
else |
520 |
p->len = outl + (6 + 6 - DATAHDR); |
521 |
#endif |
522 |
|
523 |
return p; |
524 |
} |
525 |
|
526 |
struct ping_packet : vpn_packet |
527 |
{ |
528 |
void setup (int dst, ptype type) |
529 |
{ |
530 |
set_hdr (type, dst); |
531 |
len = sizeof (*this) - sizeof (net_packet); |
532 |
} |
533 |
}; |
534 |
|
535 |
struct config_packet : vpn_packet |
536 |
{ |
537 |
// actually, hmaclen cannot be checked because the hmac |
538 |
// field comes before this data, so peers with other |
539 |
// hmacs simply will not work. |
540 |
u8 prot_major, prot_minor, randsize, hmaclen; |
541 |
u8 flags, challengelen, pad2, pad3; |
542 |
u32 cipher_nid, digest_nid, hmac_nid; |
543 |
|
544 |
const u8 curflags () const |
545 |
{ |
546 |
return 0x80 |
547 |
| (ENABLE_COMPRESSION ? 0x01 : 0x00); |
548 |
} |
549 |
|
550 |
void setup (ptype type, int dst); |
551 |
bool chk_config () const; |
552 |
}; |
553 |
|
554 |
void config_packet::setup (ptype type, int dst) |
555 |
{ |
556 |
prot_major = PROTOCOL_MAJOR; |
557 |
prot_minor = PROTOCOL_MINOR; |
558 |
randsize = RAND_SIZE; |
559 |
hmaclen = HMACLENGTH; |
560 |
flags = curflags (); |
561 |
challengelen = sizeof (rsachallenge); |
562 |
|
563 |
cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); |
564 |
digest_nid = htonl (EVP_MD_type (RSA_HASH)); |
565 |
hmac_nid = htonl (EVP_MD_type (DIGEST)); |
566 |
|
567 |
len = sizeof (*this) - sizeof (net_packet); |
568 |
set_hdr (type, dst); |
569 |
} |
570 |
|
571 |
bool config_packet::chk_config () const |
572 |
{ |
573 |
return prot_major == PROTOCOL_MAJOR |
574 |
&& randsize == RAND_SIZE |
575 |
&& hmaclen == HMACLENGTH |
576 |
&& flags == curflags () |
577 |
&& challengelen == sizeof (rsachallenge) |
578 |
&& cipher_nid == htonl (EVP_CIPHER_nid (CIPHER)) |
579 |
&& digest_nid == htonl (EVP_MD_type (RSA_HASH)) |
580 |
&& hmac_nid == htonl (EVP_MD_type (DIGEST)); |
581 |
} |
582 |
|
583 |
struct auth_req_packet : config_packet |
584 |
{ |
585 |
char magic[8]; |
586 |
u8 initiate, can_recv; // false if this is just an automatic reply |
587 |
u8 pad2, pad3; |
588 |
rsaid id; |
589 |
rsaencrdata encr; |
590 |
|
591 |
auth_req_packet (int dst, bool initiate_, u8 can_recv_) |
592 |
{ |
593 |
config_packet::setup (PT_AUTH_REQ, dst); |
594 |
strncpy (magic, MAGIC, 8); |
595 |
initiate = !!initiate_; |
596 |
can_recv = can_recv_; |
597 |
|
598 |
len = sizeof (*this) - sizeof (net_packet); |
599 |
} |
600 |
}; |
601 |
|
602 |
struct auth_res_packet : config_packet |
603 |
{ |
604 |
rsaid id; |
605 |
u8 pad1, pad2, pad3; |
606 |
u8 response_len; // encrypted length |
607 |
rsaresponse response; |
608 |
|
609 |
auth_res_packet (int dst) |
610 |
{ |
611 |
config_packet::setup (PT_AUTH_RES, dst); |
612 |
|
613 |
len = sizeof (*this) - sizeof (net_packet); |
614 |
} |
615 |
}; |
616 |
|
617 |
struct connect_req_packet : vpn_packet |
618 |
{ |
619 |
u8 id; |
620 |
u8 pad1, pad2, pad3; |
621 |
|
622 |
connect_req_packet (int dst, int id_) |
623 |
{ |
624 |
id = id_; |
625 |
set_hdr (PT_CONNECT_REQ, dst); |
626 |
len = sizeof (*this) - sizeof (net_packet); |
627 |
} |
628 |
}; |
629 |
|
630 |
struct connect_info_packet : vpn_packet |
631 |
{ |
632 |
u8 id, can_recv; |
633 |
u8 pad1, pad2; |
634 |
sockinfo si; |
635 |
|
636 |
connect_info_packet (int dst, int id_, sockinfo &si_, u8 can_recv_) |
637 |
{ |
638 |
id = id_; |
639 |
can_recv = can_recv_; |
640 |
si = si_; |
641 |
set_hdr (PT_CONNECT_INFO, dst); |
642 |
|
643 |
len = sizeof (*this) - sizeof (net_packet); |
644 |
} |
645 |
}; |
646 |
|
647 |
///////////////////////////////////////////////////////////////////////////// |
648 |
|
649 |
void |
650 |
connection::reset_dstaddr () |
651 |
{ |
652 |
si.set (conf); |
653 |
} |
654 |
|
655 |
void |
656 |
connection::send_ping (const sockinfo &si, u8 pong) |
657 |
{ |
658 |
ping_packet *pkt = new ping_packet; |
659 |
|
660 |
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
661 |
send_vpn_packet (pkt, si, IPTOS_LOWDELAY); |
662 |
|
663 |
delete pkt; |
664 |
} |
665 |
|
666 |
void |
667 |
connection::send_reset (const sockinfo &si) |
668 |
{ |
669 |
if (reset_rate_limiter.can (si) && connectmode != conf_node::C_DISABLED) |
670 |
{ |
671 |
config_packet *pkt = new config_packet; |
672 |
|
673 |
pkt->setup (vpn_packet::PT_RESET, conf->id); |
674 |
send_vpn_packet (pkt, si, IPTOS_MINCOST); |
675 |
|
676 |
delete pkt; |
677 |
} |
678 |
} |
679 |
|
680 |
void |
681 |
connection::send_auth_request (const sockinfo &si, bool initiate) |
682 |
{ |
683 |
auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->can_recv); |
684 |
|
685 |
// the next line is very conservative |
686 |
prot_send = best_protocol (THISNODE->can_send & THISNODE->can_recv & conf->can_recv); |
687 |
|
688 |
rsachallenge chg; |
689 |
|
690 |
rsa_cache.gen (pkt->id, chg); |
691 |
|
692 |
if (0 > RSA_public_encrypt (sizeof chg, |
693 |
(unsigned char *)&chg, (unsigned char *)&pkt->encr, |
694 |
conf->rsa_key, RSA_PKCS1_OAEP_PADDING)) |
695 |
fatal ("RSA_public_encrypt error"); |
696 |
|
697 |
slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)si); |
698 |
|
699 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
700 |
|
701 |
delete pkt; |
702 |
} |
703 |
|
704 |
void |
705 |
connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg) |
706 |
{ |
707 |
auth_res_packet *pkt = new auth_res_packet (conf->id); |
708 |
|
709 |
pkt->id = id; |
710 |
|
711 |
rsa_hash (id, chg, pkt->response); |
712 |
|
713 |
pkt->hmac_set (octx); |
714 |
|
715 |
slog (L_TRACE, ">>%d PT_AUTH_RES [%s]", conf->id, (const char *)si); |
716 |
|
717 |
send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
718 |
|
719 |
delete pkt; |
720 |
} |
721 |
|
722 |
void |
723 |
connection::establish_connection_cb (tstamp &ts) |
724 |
{ |
725 |
if (ictx || conf == THISNODE |
726 |
|| connectmode == conf_node::C_NEVER |
727 |
|| connectmode == conf_node::C_DISABLED) |
728 |
ts = TSTAMP_CANCEL; |
729 |
else if (ts <= NOW) |
730 |
{ |
731 |
double retry_int = double (retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2)) * 0.6; |
732 |
|
733 |
if (retry_int < 3600 * 8) |
734 |
retry_cnt++; |
735 |
|
736 |
ts = NOW + retry_int; |
737 |
|
738 |
if (conf->hostname) |
739 |
{ |
740 |
reset_dstaddr (); |
741 |
if (si.host && auth_rate_limiter.can (si)) |
742 |
{ |
743 |
if (retry_cnt < 4) |
744 |
send_auth_request (si, true); |
745 |
else |
746 |
send_ping (si, 0); |
747 |
} |
748 |
} |
749 |
else |
750 |
vpn->connect_request (conf->id); |
751 |
} |
752 |
} |
753 |
|
754 |
void |
755 |
connection::reset_connection () |
756 |
{ |
757 |
if (ictx && octx) |
758 |
{ |
759 |
slog (L_INFO, _("%s(%s): connection lost"), |
760 |
conf->nodename, (const char *)si); |
761 |
|
762 |
if (::conf.script_node_down) |
763 |
run_script (run_script_cb (this, &connection::script_node_down), false); |
764 |
} |
765 |
|
766 |
delete ictx; ictx = 0; |
767 |
delete octx; octx = 0; |
768 |
|
769 |
si.host= 0; |
770 |
|
771 |
last_activity = 0; |
772 |
retry_cnt = 0; |
773 |
|
774 |
rekey.reset (); |
775 |
keepalive.reset (); |
776 |
establish_connection.reset (); |
777 |
} |
778 |
|
779 |
void |
780 |
connection::shutdown () |
781 |
{ |
782 |
if (ictx && octx) |
783 |
send_reset (si); |
784 |
|
785 |
reset_connection (); |
786 |
} |
787 |
|
788 |
void |
789 |
connection::rekey_cb (tstamp &ts) |
790 |
{ |
791 |
ts = TSTAMP_CANCEL; |
792 |
|
793 |
reset_connection (); |
794 |
establish_connection (); |
795 |
} |
796 |
|
797 |
void |
798 |
connection::send_data_packet (tap_packet *pkt, bool broadcast) |
799 |
{ |
800 |
vpndata_packet *p = new vpndata_packet; |
801 |
int tos = 0; |
802 |
|
803 |
if (conf->inherit_tos |
804 |
&& (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP |
805 |
&& ((*pkt)[14] & 0xf0) == 0x40) // IPv4 |
806 |
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
807 |
|
808 |
p->setup (this, broadcast ? 0 : conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
809 |
send_vpn_packet (p, si, tos); |
810 |
|
811 |
delete p; |
812 |
|
813 |
if (oseqno > MAX_SEQNO) |
814 |
rekey (); |
815 |
} |
816 |
|
817 |
void |
818 |
connection::inject_data_packet (tap_packet *pkt, bool broadcast) |
819 |
{ |
820 |
if (ictx && octx) |
821 |
send_data_packet (pkt, broadcast); |
822 |
else |
823 |
{ |
824 |
if (!broadcast)//DDDD |
825 |
queue.put (new tap_packet (*pkt)); |
826 |
|
827 |
establish_connection (); |
828 |
} |
829 |
} |
830 |
|
831 |
void |
832 |
connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
833 |
{ |
834 |
last_activity = NOW; |
835 |
|
836 |
slog (L_NOISE, "<<%d received packet type %d from %d to %d", |
837 |
conf->id, pkt->typ (), pkt->src (), pkt->dst ()); |
838 |
|
839 |
switch (pkt->typ ()) |
840 |
{ |
841 |
case vpn_packet::PT_PING: |
842 |
// we send pings instead of auth packets after some retries, |
843 |
// so reset the retry counter and establish a connection |
844 |
// when we receive a ping. |
845 |
if (!ictx) |
846 |
{ |
847 |
if (auth_rate_limiter.can (rsi)) |
848 |
send_auth_request (rsi, true); |
849 |
} |
850 |
else |
851 |
send_ping (rsi, 1); // pong |
852 |
|
853 |
break; |
854 |
|
855 |
case vpn_packet::PT_PONG: |
856 |
break; |
857 |
|
858 |
case vpn_packet::PT_RESET: |
859 |
{ |
860 |
reset_connection (); |
861 |
|
862 |
config_packet *p = (config_packet *) pkt; |
863 |
|
864 |
if (!p->chk_config ()) |
865 |
{ |
866 |
slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"), |
867 |
conf->nodename, (const char *)rsi); |
868 |
connectmode = conf_node::C_DISABLED; |
869 |
} |
870 |
else if (connectmode == conf_node::C_ALWAYS) |
871 |
establish_connection (); |
872 |
} |
873 |
break; |
874 |
|
875 |
case vpn_packet::PT_AUTH_REQ: |
876 |
if (auth_rate_limiter.can (rsi)) |
877 |
{ |
878 |
auth_req_packet *p = (auth_req_packet *) pkt; |
879 |
|
880 |
slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate); |
881 |
|
882 |
if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) |
883 |
{ |
884 |
if (p->prot_minor != PROTOCOL_MINOR) |
885 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
886 |
conf->nodename, (const char *)rsi, |
887 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
888 |
|
889 |
if (p->initiate) |
890 |
send_auth_request (rsi, false); |
891 |
|
892 |
rsachallenge k; |
893 |
|
894 |
if (0 > RSA_private_decrypt (sizeof (p->encr), |
895 |
(unsigned char *)&p->encr, (unsigned char *)&k, |
896 |
::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
897 |
slog (L_ERR, _("%s(%s): challenge illegal or corrupted"), |
898 |
conf->nodename, (const char *)rsi); |
899 |
else |
900 |
{ |
901 |
retry_cnt = 0; |
902 |
establish_connection.set (NOW + 8); //? ;) |
903 |
keepalive.reset (); |
904 |
rekey.reset (); |
905 |
|
906 |
delete ictx; |
907 |
ictx = 0; |
908 |
|
909 |
delete octx; |
910 |
|
911 |
octx = new crypto_ctx (k, 1); |
912 |
oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; |
913 |
|
914 |
conf->can_recv = p->can_recv; |
915 |
send_auth_response (rsi, p->id, k); |
916 |
|
917 |
break; |
918 |
} |
919 |
} |
920 |
|
921 |
send_reset (rsi); |
922 |
} |
923 |
|
924 |
break; |
925 |
|
926 |
case vpn_packet::PT_AUTH_RES: |
927 |
{ |
928 |
auth_res_packet *p = (auth_res_packet *) pkt; |
929 |
|
930 |
slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id); |
931 |
|
932 |
if (p->chk_config ()) |
933 |
{ |
934 |
if (p->prot_minor != PROTOCOL_MINOR) |
935 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
936 |
conf->nodename, (const char *)rsi, |
937 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
938 |
|
939 |
rsachallenge chg; |
940 |
|
941 |
if (!rsa_cache.find (p->id, chg)) |
942 |
slog (L_ERR, _("%s(%s): unrequested auth response"), |
943 |
conf->nodename, (const char *)rsi); |
944 |
else |
945 |
{ |
946 |
crypto_ctx *cctx = new crypto_ctx (chg, 0); |
947 |
|
948 |
if (!p->hmac_chk (cctx)) |
949 |
slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" |
950 |
"could be an attack, or just corruption or an synchronization error"), |
951 |
conf->nodename, (const char *)rsi); |
952 |
else |
953 |
{ |
954 |
rsaresponse h; |
955 |
|
956 |
rsa_hash (p->id, chg, h); |
957 |
|
958 |
if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) |
959 |
{ |
960 |
prot_minor = p->prot_minor; |
961 |
|
962 |
delete ictx; ictx = cctx; |
963 |
|
964 |
iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid |
965 |
|
966 |
si = rsi; |
967 |
|
968 |
rekey.set (NOW + ::conf.rekey); |
969 |
keepalive.set (NOW + ::conf.keepalive); |
970 |
|
971 |
// send queued packets |
972 |
while (tap_packet *p = queue.get ()) |
973 |
{ |
974 |
send_data_packet (p); |
975 |
delete p; |
976 |
} |
977 |
|
978 |
connectmode = conf->connectmode; |
979 |
|
980 |
slog (L_INFO, _("%s(%s): connection established, protocol version %d.%d"), |
981 |
conf->nodename, (const char *)rsi, |
982 |
p->prot_major, p->prot_minor); |
983 |
|
984 |
if (::conf.script_node_up) |
985 |
run_script (run_script_cb (this, &connection::script_node_up), false); |
986 |
|
987 |
break; |
988 |
} |
989 |
else |
990 |
slog (L_ERR, _("%s(%s): sent and received challenge do not match"), |
991 |
conf->nodename, (const char *)rsi); |
992 |
} |
993 |
|
994 |
delete cctx; |
995 |
} |
996 |
} |
997 |
} |
998 |
|
999 |
send_reset (rsi); |
1000 |
break; |
1001 |
|
1002 |
case vpn_packet::PT_DATA_COMPRESSED: |
1003 |
#if !ENABLE_COMPRESSION |
1004 |
send_reset (rsi); |
1005 |
break; |
1006 |
#endif |
1007 |
|
1008 |
case vpn_packet::PT_DATA_UNCOMPRESSED: |
1009 |
|
1010 |
if (ictx && octx) |
1011 |
{ |
1012 |
vpndata_packet *p = (vpndata_packet *)pkt; |
1013 |
|
1014 |
if (rsi == si) |
1015 |
{ |
1016 |
if (!p->hmac_chk (ictx)) |
1017 |
slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" |
1018 |
"could be an attack, or just corruption or an synchronization error"), |
1019 |
conf->nodename, (const char *)rsi); |
1020 |
else |
1021 |
{ |
1022 |
u32 seqno; |
1023 |
tap_packet *d = p->unpack (this, seqno); |
1024 |
|
1025 |
if (iseqno.recv_ok (seqno)) |
1026 |
{ |
1027 |
vpn->tap->send (d); |
1028 |
|
1029 |
if (p->dst () == 0) // re-broadcast |
1030 |
for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i) |
1031 |
{ |
1032 |
connection *c = *i; |
1033 |
|
1034 |
if (c->conf != THISNODE && c->conf != conf) |
1035 |
c->inject_data_packet (d); |
1036 |
} |
1037 |
|
1038 |
delete d; |
1039 |
|
1040 |
break; |
1041 |
} |
1042 |
} |
1043 |
} |
1044 |
else |
1045 |
slog (L_ERR, _("received data packet from unknown source %s"), (const char *)rsi); |
1046 |
} |
1047 |
|
1048 |
send_reset (rsi); |
1049 |
break; |
1050 |
|
1051 |
case vpn_packet::PT_CONNECT_REQ: |
1052 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1053 |
{ |
1054 |
connect_req_packet *p = (connect_req_packet *) pkt; |
1055 |
|
1056 |
assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything |
1057 |
|
1058 |
connection *c = vpn->conns[p->id - 1]; |
1059 |
|
1060 |
slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n", |
1061 |
conf->id, p->id, c->ictx && c->octx); |
1062 |
|
1063 |
if (c->ictx && c->octx) |
1064 |
{ |
1065 |
// send connect_info packets to both sides, in case one is |
1066 |
// behind a nat firewall (or both ;) |
1067 |
{ |
1068 |
slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", |
1069 |
c->conf->id, conf->id, (const char *)si); |
1070 |
|
1071 |
connect_info_packet *r = new connect_info_packet (c->conf->id, conf->id, si, conf->can_recv); |
1072 |
|
1073 |
r->hmac_set (c->octx); |
1074 |
send_vpn_packet (r, c->si); |
1075 |
|
1076 |
delete r; |
1077 |
} |
1078 |
|
1079 |
{ |
1080 |
slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", |
1081 |
conf->id, c->conf->id, (const char *)c->si); |
1082 |
|
1083 |
connect_info_packet *r = new connect_info_packet (conf->id, c->conf->id, c->si, c->conf->can_recv); |
1084 |
|
1085 |
r->hmac_set (octx); |
1086 |
send_vpn_packet (r, si); |
1087 |
|
1088 |
delete r; |
1089 |
} |
1090 |
} |
1091 |
} |
1092 |
|
1093 |
break; |
1094 |
|
1095 |
case vpn_packet::PT_CONNECT_INFO: |
1096 |
if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) |
1097 |
{ |
1098 |
connect_info_packet *p = (connect_info_packet *) pkt; |
1099 |
|
1100 |
assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything |
1101 |
|
1102 |
connection *c = vpn->conns[p->id - 1]; |
1103 |
|
1104 |
slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)", |
1105 |
conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx); |
1106 |
|
1107 |
c->conf->can_recv = p->can_recv; |
1108 |
c->send_auth_request (p->si, true); |
1109 |
} |
1110 |
|
1111 |
break; |
1112 |
|
1113 |
default: |
1114 |
send_reset (rsi); |
1115 |
break; |
1116 |
|
1117 |
} |
1118 |
} |
1119 |
|
1120 |
void connection::keepalive_cb (tstamp &ts) |
1121 |
{ |
1122 |
if (NOW >= last_activity + ::conf.keepalive + 30) |
1123 |
{ |
1124 |
reset_connection (); |
1125 |
establish_connection (); |
1126 |
} |
1127 |
else if (NOW < last_activity + ::conf.keepalive) |
1128 |
ts = last_activity + ::conf.keepalive; |
1129 |
else if (conf->connectmode != conf_node::C_ONDEMAND |
1130 |
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
1131 |
{ |
1132 |
send_ping (si); |
1133 |
ts = NOW + 5; |
1134 |
} |
1135 |
else |
1136 |
reset_connection (); |
1137 |
|
1138 |
} |
1139 |
|
1140 |
void connection::connect_request (int id) |
1141 |
{ |
1142 |
connect_req_packet *p = new connect_req_packet (conf->id, id); |
1143 |
|
1144 |
slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", id, conf->id); |
1145 |
p->hmac_set (octx); |
1146 |
send_vpn_packet (p, si); |
1147 |
|
1148 |
delete p; |
1149 |
} |
1150 |
|
1151 |
void connection::script_node () |
1152 |
{ |
1153 |
vpn->script_if_up (0); |
1154 |
|
1155 |
char *env; |
1156 |
asprintf (&env, "DESTID=%d", conf->id); putenv (env); |
1157 |
asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); |
1158 |
asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); |
1159 |
asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); |
1160 |
} |
1161 |
|
1162 |
const char *connection::script_node_up (int) |
1163 |
{ |
1164 |
script_node (); |
1165 |
|
1166 |
putenv ("STATE=up"); |
1167 |
|
1168 |
return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; |
1169 |
} |
1170 |
|
1171 |
const char *connection::script_node_down (int) |
1172 |
{ |
1173 |
script_node (); |
1174 |
|
1175 |
putenv ("STATE=down"); |
1176 |
|
1177 |
return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; |
1178 |
} |
1179 |
|
1180 |
// send a vpn packet out to other hosts |
1181 |
void |
1182 |
connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
1183 |
{ |
1184 |
if (prot_send & PROT_IPv4) |
1185 |
vpn->send_ipv4_packet (pkt, si, tos); |
1186 |
else |
1187 |
vpn->send_udpv4_packet (pkt, si, tos); |
1188 |
} |
1189 |
|
1190 |
connection::connection(struct vpn *vpn_) |
1191 |
: vpn(vpn_) |
1192 |
, rekey (this, &connection::rekey_cb) |
1193 |
, keepalive (this, &connection::keepalive_cb) |
1194 |
, establish_connection (this, &connection::establish_connection_cb) |
1195 |
{ |
1196 |
octx = ictx = 0; |
1197 |
retry_cnt = 0; |
1198 |
|
1199 |
connectmode = conf_node::C_ALWAYS; // initial setting |
1200 |
reset_connection (); |
1201 |
} |
1202 |
|
1203 |
connection::~connection () |
1204 |
{ |
1205 |
shutdown (); |
1206 |
} |
1207 |
|
1208 |
///////////////////////////////////////////////////////////////////////////// |
1209 |
|
1210 |
const char *vpn::script_if_up (int) |
1211 |
{ |
1212 |
// the tunnel device mtu should be the physical mtu - overhead |
1213 |
// the tricky part is rounding to the cipher key blocksize |
1214 |
int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - MAX_OVERHEAD; |
1215 |
mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
1216 |
mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round |
1217 |
mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
1218 |
|
1219 |
char *env; |
1220 |
asprintf (&env, "CONFBASE=%s", confbase); |
1221 |
putenv (env); |
1222 |
asprintf (&env, "NODENAME=%s", THISNODE->nodename); |
1223 |
putenv (env); |
1224 |
asprintf (&env, "NODEID=%d", THISNODE->id); |
1225 |
putenv (env); |
1226 |
asprintf (&env, "IFNAME=%s", tap->interface ()); |
1227 |
putenv (env); |
1228 |
asprintf (&env, "MTU=%d", mtu); |
1229 |
putenv (env); |
1230 |
asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x", |
1231 |
0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8, |
1232 |
THISNODE->id & 0xff); |
1233 |
putenv (env); |
1234 |
|
1235 |
return ::conf.script_if_up ? ::conf.script_if_up : "if-up"; |
1236 |
} |
1237 |
|
1238 |
int |
1239 |
vpn::setup () |
1240 |
{ |
1241 |
u8 prots = 0; |
1242 |
|
1243 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); |
1244 |
i != conf.nodes.end (); ++i) |
1245 |
prots |= (*i)->can_send | (*i)->can_recv; |
1246 |
|
1247 |
sockinfo si; |
1248 |
|
1249 |
si.set (THISNODE); |
1250 |
|
1251 |
udpv4_fd = -1; |
1252 |
|
1253 |
if (prots & PROT_UDPv4) |
1254 |
{ |
1255 |
udpv4_fd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
1256 |
|
1257 |
if (udpv4_fd < 0) |
1258 |
return -1; |
1259 |
|
1260 |
if (bind (udpv4_fd, si.sav4 (), si.salenv4 ())) |
1261 |
{ |
1262 |
slog (L_ERR, _("can't bind udpv4 to %s: %s"), (const char *)si, strerror (errno)); |
1263 |
exit (1); |
1264 |
} |
1265 |
|
1266 |
#ifdef IP_MTU_DISCOVER |
1267 |
// this I really consider a linux bug. I am neither connected |
1268 |
// nor do I fragment myself. Linux still sets DF and doesn't |
1269 |
// fragment for me sometimes. |
1270 |
{ |
1271 |
int oval = IP_PMTUDISC_DONT; |
1272 |
setsockopt (udpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
1273 |
} |
1274 |
#endif |
1275 |
|
1276 |
// standard daemon practise... |
1277 |
{ |
1278 |
int oval = 1; |
1279 |
setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
1280 |
} |
1281 |
|
1282 |
udpv4_ev_watcher.start (udpv4_fd, POLLIN); |
1283 |
} |
1284 |
|
1285 |
ipv4_fd = -1; |
1286 |
if (prots & PROT_IPv4) |
1287 |
{ |
1288 |
ipv4_fd = socket (PF_INET, SOCK_RAW, ::conf.ip_proto); |
1289 |
|
1290 |
if (ipv4_fd < 0) |
1291 |
return -1; |
1292 |
|
1293 |
if (bind (ipv4_fd, si.sav4 (), si.salenv4 ())) |
1294 |
{ |
1295 |
slog (L_ERR, _("can't bind ipv4 socket to %s: %s"), (const char *)si, strerror (errno)); |
1296 |
exit (1); |
1297 |
} |
1298 |
|
1299 |
#ifdef IP_MTU_DISCOVER |
1300 |
// this I really consider a linux bug. I am neither connected |
1301 |
// nor do I fragment myself. Linux still sets DF and doesn't |
1302 |
// fragment for me sometimes. |
1303 |
{ |
1304 |
int oval = IP_PMTUDISC_DONT; |
1305 |
setsockopt (ipv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
1306 |
} |
1307 |
#endif |
1308 |
|
1309 |
ipv4_ev_watcher.start (ipv4_fd, POLLIN); |
1310 |
} |
1311 |
|
1312 |
tap = new tap_device (); |
1313 |
if (!tap) //D this, of course, never catches |
1314 |
{ |
1315 |
slog (L_ERR, _("cannot create network interface '%s'"), conf.ifname); |
1316 |
exit (1); |
1317 |
} |
1318 |
|
1319 |
run_script (run_script_cb (this, &vpn::script_if_up), true); |
1320 |
|
1321 |
tap_ev_watcher.start (tap->fd, POLLIN); |
1322 |
|
1323 |
reconnect_all (); |
1324 |
|
1325 |
return 0; |
1326 |
} |
1327 |
|
1328 |
void |
1329 |
vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
1330 |
{ |
1331 |
setsockopt (ipv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
1332 |
sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
1333 |
} |
1334 |
|
1335 |
void |
1336 |
vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
1337 |
{ |
1338 |
setsockopt (udpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
1339 |
sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
1340 |
} |
1341 |
|
1342 |
void |
1343 |
vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
1344 |
{ |
1345 |
unsigned int src = pkt->src (); |
1346 |
unsigned int dst = pkt->dst (); |
1347 |
|
1348 |
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d"), |
1349 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
1350 |
|
1351 |
if (dst > conns.size () || pkt->typ () >= vpn_packet::PT_MAX) |
1352 |
slog (L_WARN, _("<<? received CORRUPTED packet type %d from %d to %d"), |
1353 |
pkt->typ (), pkt->src (), pkt->dst ()); |
1354 |
else if (dst == 0 && !THISNODE->routerprio) |
1355 |
slog (L_WARN, _("<<%d received broadcast, but we are no router"), dst); |
1356 |
else if (dst != 0 && dst != THISNODE->id) |
1357 |
slog (L_WARN, |
1358 |
_("received frame for node %d ('%s') from %s, but this is node %d ('%s')"), |
1359 |
dst, conns[dst - 1]->conf->nodename, |
1360 |
(const char *)rsi, |
1361 |
THISNODE->id, THISNODE->nodename); |
1362 |
else if (src == 0 || src > conns.size ()) |
1363 |
slog (L_WARN, _("received frame from unknown node %d (%s)"), |
1364 |
src, (const char *)rsi); |
1365 |
else |
1366 |
conns[src - 1]->recv_vpn_packet (pkt, rsi); |
1367 |
} |
1368 |
|
1369 |
void |
1370 |
vpn::udpv4_ev (short revents) |
1371 |
{ |
1372 |
if (revents & (POLLIN | POLLERR)) |
1373 |
{ |
1374 |
vpn_packet *pkt = new vpn_packet; |
1375 |
struct sockaddr_in sa; |
1376 |
socklen_t sa_len = sizeof (sa); |
1377 |
int len; |
1378 |
|
1379 |
len = recvfrom (udpv4_fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
1380 |
|
1381 |
sockinfo si(sa); |
1382 |
|
1383 |
if (len > 0) |
1384 |
{ |
1385 |
pkt->len = len; |
1386 |
|
1387 |
recv_vpn_packet (pkt, si); |
1388 |
} |
1389 |
else |
1390 |
{ |
1391 |
// probably ECONNRESET or somesuch |
1392 |
slog (L_DEBUG, _("%s: %s"), (const char *)si, strerror (errno)); |
1393 |
} |
1394 |
|
1395 |
delete pkt; |
1396 |
} |
1397 |
else if (revents & POLLHUP) |
1398 |
{ |
1399 |
// this cannot ;) happen on udp sockets |
1400 |
slog (L_ERR, _("FATAL: POLLHUP on udp v4 fd, terminating.")); |
1401 |
exit (1); |
1402 |
} |
1403 |
else |
1404 |
{ |
1405 |
slog (L_ERR, |
1406 |
_("FATAL: unknown revents %08x in socket, terminating\n"), |
1407 |
revents); |
1408 |
exit (1); |
1409 |
} |
1410 |
} |
1411 |
|
1412 |
void |
1413 |
vpn::ipv4_ev (short revents) |
1414 |
{ |
1415 |
if (revents & (POLLIN | POLLERR)) |
1416 |
{ |
1417 |
vpn_packet *pkt = new vpn_packet; |
1418 |
struct sockaddr_in sa; |
1419 |
socklen_t sa_len = sizeof (sa); |
1420 |
int len; |
1421 |
|
1422 |
len = recvfrom (ipv4_fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
1423 |
|
1424 |
sockinfo si(sa, PROT_IPv4); |
1425 |
|
1426 |
if (len > 0) |
1427 |
{ |
1428 |
pkt->len = len; |
1429 |
|
1430 |
// raw sockets deliver the ipv4, but don't expect it on sends |
1431 |
// this is slow, but... |
1432 |
pkt->skip_hdr (IP_OVERHEAD); |
1433 |
|
1434 |
recv_vpn_packet (pkt, si); |
1435 |
} |
1436 |
else |
1437 |
{ |
1438 |
// probably ECONNRESET or somesuch |
1439 |
slog (L_DEBUG, _("%s: %s"), (const char *)si, strerror (errno)); |
1440 |
} |
1441 |
|
1442 |
delete pkt; |
1443 |
} |
1444 |
else if (revents & POLLHUP) |
1445 |
{ |
1446 |
// this cannot ;) happen on udp sockets |
1447 |
slog (L_ERR, _("FATAL: POLLHUP on ipv4 fd, terminating.")); |
1448 |
exit (1); |
1449 |
} |
1450 |
else |
1451 |
{ |
1452 |
slog (L_ERR, |
1453 |
_("FATAL: unknown revents %08x in socket, terminating\n"), |
1454 |
revents); |
1455 |
exit (1); |
1456 |
} |
1457 |
} |
1458 |
|
1459 |
void |
1460 |
vpn::tap_ev (short revents) |
1461 |
{ |
1462 |
if (revents & POLLIN) |
1463 |
{ |
1464 |
/* process data */ |
1465 |
tap_packet *pkt; |
1466 |
|
1467 |
pkt = tap->recv (); |
1468 |
|
1469 |
int dst = mac2id (pkt->dst); |
1470 |
int src = mac2id (pkt->src); |
1471 |
|
1472 |
if (src != THISNODE->id) |
1473 |
{ |
1474 |
slog (L_ERR, _("FATAL: tap packet not originating on current node received, terminating.")); |
1475 |
exit (1); |
1476 |
} |
1477 |
|
1478 |
if (dst == THISNODE->id) |
1479 |
{ |
1480 |
slog (L_ERR, _("FATAL: tap packet destined for current node received, terminating.")); |
1481 |
exit (1); |
1482 |
} |
1483 |
|
1484 |
if (dst > conns.size ()) |
1485 |
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
1486 |
else |
1487 |
{ |
1488 |
if (dst) |
1489 |
{ |
1490 |
// unicast |
1491 |
if (dst != THISNODE->id) |
1492 |
conns[dst - 1]->inject_data_packet (pkt); |
1493 |
} |
1494 |
else |
1495 |
{ |
1496 |
// broadcast, first check router, then self, then english |
1497 |
connection *router = find_router (); |
1498 |
|
1499 |
if (router) |
1500 |
router->inject_data_packet (pkt, true); |
1501 |
else |
1502 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1503 |
if ((*c)->conf != THISNODE) |
1504 |
(*c)->inject_data_packet (pkt); |
1505 |
} |
1506 |
} |
1507 |
|
1508 |
delete pkt; |
1509 |
} |
1510 |
else if (revents & (POLLHUP | POLLERR)) |
1511 |
{ |
1512 |
slog (L_ERR, _("FATAL: POLLHUP or POLLERR on network device fd, terminating.")); |
1513 |
exit (1); |
1514 |
} |
1515 |
else |
1516 |
abort (); |
1517 |
} |
1518 |
|
1519 |
void |
1520 |
vpn::event_cb (tstamp &ts) |
1521 |
{ |
1522 |
if (events) |
1523 |
{ |
1524 |
if (events & EVENT_SHUTDOWN) |
1525 |
{ |
1526 |
slog (L_INFO, _("preparing shutdown...")); |
1527 |
|
1528 |
shutdown_all (); |
1529 |
|
1530 |
remove_pid (pidfilename); |
1531 |
|
1532 |
slog (L_INFO, _("terminating")); |
1533 |
|
1534 |
exit (0); |
1535 |
} |
1536 |
|
1537 |
if (events & EVENT_RECONNECT) |
1538 |
{ |
1539 |
slog (L_INFO, _("forced reconnect")); |
1540 |
|
1541 |
reconnect_all (); |
1542 |
} |
1543 |
|
1544 |
events = 0; |
1545 |
} |
1546 |
|
1547 |
ts = TSTAMP_CANCEL; |
1548 |
} |
1549 |
|
1550 |
void |
1551 |
vpn::shutdown_all () |
1552 |
{ |
1553 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1554 |
(*c)->shutdown (); |
1555 |
} |
1556 |
|
1557 |
void |
1558 |
vpn::reconnect_all () |
1559 |
{ |
1560 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1561 |
delete *c; |
1562 |
|
1563 |
conns.clear (); |
1564 |
|
1565 |
auth_rate_limiter.clear (); |
1566 |
reset_rate_limiter.clear (); |
1567 |
|
1568 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); |
1569 |
i != conf.nodes.end (); ++i) |
1570 |
{ |
1571 |
connection *conn = new connection (this); |
1572 |
|
1573 |
conn->conf = *i; |
1574 |
conns.push_back (conn); |
1575 |
|
1576 |
conn->establish_connection (); |
1577 |
} |
1578 |
} |
1579 |
|
1580 |
connection *vpn::find_router () |
1581 |
{ |
1582 |
u32 prio = 0; |
1583 |
connection *router = 0; |
1584 |
|
1585 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
1586 |
{ |
1587 |
connection *c = *i; |
1588 |
|
1589 |
if (c->conf->routerprio > prio |
1590 |
&& c->connectmode == conf_node::C_ALWAYS |
1591 |
&& c->conf != THISNODE |
1592 |
&& c->ictx && c->octx) |
1593 |
{ |
1594 |
prio = c->conf->routerprio; |
1595 |
router = c; |
1596 |
} |
1597 |
} |
1598 |
|
1599 |
return router; |
1600 |
} |
1601 |
|
1602 |
void vpn::connect_request (int id) |
1603 |
{ |
1604 |
connection *c = find_router (); |
1605 |
|
1606 |
if (c) |
1607 |
c->connect_request (id); |
1608 |
//else // does not work, because all others must connect to the same router |
1609 |
// // no router found, aggressively connect to all routers |
1610 |
// for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
1611 |
// if ((*i)->conf->routerprio) |
1612 |
// (*i)->establish_connection (); |
1613 |
} |
1614 |
|
1615 |
void |
1616 |
connection::dump_status () |
1617 |
{ |
1618 |
slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id); |
1619 |
slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"), |
1620 |
connectmode, conf->connectmode, (const char *)si, (int)prot_minor); |
1621 |
slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"), |
1622 |
(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt); |
1623 |
slog (L_NOTICE, _(" establish_conn %ld / rekey %ld / keepalive %ld"), |
1624 |
(long)(establish_connection.at), (long)(rekey.at), (long)(keepalive.at)); |
1625 |
} |
1626 |
|
1627 |
void |
1628 |
vpn::dump_status () |
1629 |
{ |
1630 |
slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)NOW); |
1631 |
|
1632 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1633 |
(*c)->dump_status (); |
1634 |
|
1635 |
slog (L_NOTICE, _("END status dump")); |
1636 |
} |
1637 |
|
1638 |
vpn::vpn (void) |
1639 |
: udpv4_ev_watcher(this, &vpn::udpv4_ev) |
1640 |
, ipv4_ev_watcher(this, &vpn::ipv4_ev) |
1641 |
, tap_ev_watcher(this, &vpn::tap_ev) |
1642 |
, event(this, &vpn::event_cb) |
1643 |
{ |
1644 |
} |
1645 |
|
1646 |
vpn::~vpn () |
1647 |
{ |
1648 |
} |
1649 |
|