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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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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 : private 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 (u32 host); |
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bool can (SOCKADDR *sa) { return can((u32)sa->sin_addr.s_addr); } |
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bool can (sockinfo &si) { return can((u32)si.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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} |
308 |
|
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static unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
310 |
|
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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); |
328 |
} |
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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); |
345 |
} |
346 |
|
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struct vpn_packet : hmac_packet |
348 |
{ |
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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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}; |
361 |
|
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u8 type; |
363 |
u8 srcdst, src1, dst1; |
364 |
|
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void set_hdr (ptype type, unsigned int dst); |
366 |
|
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unsigned int src () |
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{ |
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return src1 | ((srcdst >> 4) << 8); |
370 |
} |
371 |
|
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unsigned int dst () |
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{ |
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return dst1 | ((srcdst & 0xf) << 8); |
375 |
} |
376 |
|
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ptype typ () |
378 |
{ |
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return (ptype) type; |
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} |
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}; |
382 |
|
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void vpn_packet::set_hdr (ptype type, unsigned int dst) |
384 |
{ |
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this->type = type; |
386 |
|
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int src = THISNODE->id; |
388 |
|
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src1 = src; |
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srcdst = ((src >> 8) << 4) | (dst >> 8); |
391 |
dst1 = dst; |
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} |
393 |
|
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#define MAXVPNDATA (MAX_MTU - 6 - 6) |
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#define DATAHDR (sizeof (u32) + RAND_SIZE) |
396 |
|
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struct vpndata_packet:vpn_packet |
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{ |
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u8 data[MAXVPNDATA + DATAHDR]; // seqno |
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|
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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: |
404 |
|
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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; |
408 |
} |
409 |
}; |
410 |
|
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void |
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vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
413 |
{ |
414 |
EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
415 |
int outl = 0, outl2; |
416 |
ptype type = PT_DATA_UNCOMPRESSED; |
417 |
|
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#if ENABLE_COMPRESSION |
419 |
u8 cdata[MAX_MTU]; |
420 |
u32 cl; |
421 |
|
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cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
423 |
if (cl) |
424 |
{ |
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type = PT_DATA_COMPRESSED; |
426 |
d = cdata; |
427 |
l = cl + 2; |
428 |
|
429 |
d[0] = cl >> 8; |
430 |
d[1] = cl; |
431 |
} |
432 |
#endif |
433 |
|
434 |
EVP_EncryptInit_ex (cctx, 0, 0, 0, 0); |
435 |
|
436 |
struct { |
437 |
#if RAND_SIZE |
438 |
u8 rnd[RAND_SIZE]; |
439 |
#endif |
440 |
u32 seqno; |
441 |
} datahdr; |
442 |
|
443 |
datahdr.seqno = ntohl (seqno); |
444 |
#if RAND_SIZE |
445 |
RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE); |
446 |
#endif |
447 |
|
448 |
EVP_EncryptUpdate (cctx, |
449 |
(unsigned char *) data + outl, &outl2, |
450 |
(unsigned char *) &datahdr, DATAHDR); |
451 |
outl += outl2; |
452 |
|
453 |
EVP_EncryptUpdate (cctx, |
454 |
(unsigned char *) data + outl, &outl2, |
455 |
(unsigned char *) d, l); |
456 |
outl += outl2; |
457 |
|
458 |
EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2); |
459 |
outl += outl2; |
460 |
|
461 |
len = outl + data_hdr_size (); |
462 |
|
463 |
set_hdr (type, dst); |
464 |
|
465 |
hmac_set (conn->octx); |
466 |
} |
467 |
|
468 |
tap_packet * |
469 |
vpndata_packet::unpack (connection *conn, u32 &seqno) |
470 |
{ |
471 |
EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; |
472 |
int outl = 0, outl2; |
473 |
tap_packet *p = new tap_packet; |
474 |
u8 *d; |
475 |
u32 l = len - data_hdr_size (); |
476 |
|
477 |
EVP_DecryptInit_ex (cctx, 0, 0, 0, 0); |
478 |
|
479 |
#if ENABLE_COMPRESSION |
480 |
u8 cdata[MAX_MTU]; |
481 |
|
482 |
if (type == PT_DATA_COMPRESSED) |
483 |
d = cdata; |
484 |
else |
485 |
#endif |
486 |
d = &(*p)[6 + 6 - DATAHDR]; |
487 |
|
488 |
/* this overwrites part of the src mac, but we fix that later */ |
489 |
EVP_DecryptUpdate (cctx, |
490 |
d, &outl2, |
491 |
(unsigned char *)&data, len - data_hdr_size ()); |
492 |
outl += outl2; |
493 |
|
494 |
EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2); |
495 |
outl += outl2; |
496 |
|
497 |
seqno = ntohl (*(u32 *)(d + RAND_SIZE)); |
498 |
|
499 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
500 |
id2mac (src (), p->src); |
501 |
|
502 |
#if ENABLE_COMPRESSION |
503 |
if (type == PT_DATA_COMPRESSED) |
504 |
{ |
505 |
u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; |
506 |
|
507 |
p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0, |
508 |
&(*p)[6 + 6], MAX_MTU) |
509 |
+ 6 + 6; |
510 |
} |
511 |
else |
512 |
p->len = outl + (6 + 6 - DATAHDR); |
513 |
#endif |
514 |
|
515 |
return p; |
516 |
} |
517 |
|
518 |
struct ping_packet : vpn_packet |
519 |
{ |
520 |
void setup (int dst, ptype type) |
521 |
{ |
522 |
set_hdr (type, dst); |
523 |
len = sizeof (*this) - sizeof (net_packet); |
524 |
} |
525 |
}; |
526 |
|
527 |
struct config_packet : vpn_packet |
528 |
{ |
529 |
// actually, hmaclen cannot be checked because the hmac |
530 |
// field comes before this data, so peers with other |
531 |
// hmacs simply will not work. |
532 |
u8 prot_major, prot_minor, randsize, hmaclen; |
533 |
u8 flags, challengelen, pad2, pad3; |
534 |
u32 cipher_nid, digest_nid, hmac_nid; |
535 |
|
536 |
const u8 curflags () const |
537 |
{ |
538 |
return 0x80 |
539 |
| (ENABLE_COMPRESSION ? 0x01 : 0x00); |
540 |
} |
541 |
|
542 |
void setup (ptype type, int dst) |
543 |
{ |
544 |
prot_major = PROTOCOL_MAJOR; |
545 |
prot_minor = PROTOCOL_MINOR; |
546 |
randsize = RAND_SIZE; |
547 |
hmaclen = HMACLENGTH; |
548 |
flags = curflags (); |
549 |
challengelen = sizeof (rsachallenge); |
550 |
|
551 |
cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); |
552 |
digest_nid = htonl (EVP_MD_type (RSA_HASH)); |
553 |
hmac_nid = htonl (EVP_MD_type (DIGEST)); |
554 |
|
555 |
len = sizeof (*this) - sizeof (net_packet); |
556 |
set_hdr (type, dst); |
557 |
} |
558 |
|
559 |
bool chk_config () |
560 |
{ |
561 |
return prot_major == PROTOCOL_MAJOR |
562 |
&& randsize == RAND_SIZE |
563 |
&& hmaclen == HMACLENGTH |
564 |
&& flags == curflags () |
565 |
&& challengelen == sizeof (rsachallenge) |
566 |
&& cipher_nid == htonl (EVP_CIPHER_nid (CIPHER)) |
567 |
&& digest_nid == htonl (EVP_MD_type (RSA_HASH)) |
568 |
&& hmac_nid == htonl (EVP_MD_type (DIGEST)); |
569 |
} |
570 |
}; |
571 |
|
572 |
struct auth_req_packet : config_packet |
573 |
{ |
574 |
char magic[8]; |
575 |
u8 initiate; // false if this is just an automatic reply |
576 |
u8 pad1, pad2, pad3; |
577 |
rsaid id; |
578 |
rsaencrdata encr; |
579 |
|
580 |
auth_req_packet (int dst, bool initiate_) |
581 |
{ |
582 |
config_packet::setup (PT_AUTH_REQ, dst); |
583 |
initiate = !!initiate_; |
584 |
strncpy (magic, MAGIC, 8); |
585 |
len = sizeof (*this) - sizeof (net_packet); |
586 |
} |
587 |
}; |
588 |
|
589 |
struct auth_res_packet : config_packet |
590 |
{ |
591 |
rsaid id; |
592 |
u8 pad1, pad2, pad3; |
593 |
u8 response_len; // encrypted length |
594 |
rsaresponse response; |
595 |
|
596 |
auth_res_packet (int dst) |
597 |
{ |
598 |
config_packet::setup (PT_AUTH_RES, dst); |
599 |
len = sizeof (*this) - sizeof (net_packet); |
600 |
} |
601 |
}; |
602 |
|
603 |
struct connect_req_packet : vpn_packet |
604 |
{ |
605 |
u8 id; |
606 |
u8 pad1, pad2, pad3; |
607 |
|
608 |
connect_req_packet (int dst, int id_) |
609 |
{ |
610 |
id = id_; |
611 |
set_hdr (PT_CONNECT_REQ, dst); |
612 |
len = sizeof (*this) - sizeof (net_packet); |
613 |
} |
614 |
}; |
615 |
|
616 |
struct connect_info_packet : vpn_packet |
617 |
{ |
618 |
u8 id; |
619 |
u8 pad1, pad2, pad3; |
620 |
sockinfo si; |
621 |
|
622 |
connect_info_packet (int dst, int id_, sockinfo &si_) |
623 |
{ |
624 |
id = id_; |
625 |
si = si_; |
626 |
set_hdr (PT_CONNECT_INFO, dst); |
627 |
len = sizeof (*this) - sizeof (net_packet); |
628 |
} |
629 |
}; |
630 |
|
631 |
///////////////////////////////////////////////////////////////////////////// |
632 |
|
633 |
void |
634 |
fill_sa (SOCKADDR *sa, conf_node *conf) |
635 |
{ |
636 |
sa->sin_family = AF_INET; |
637 |
sa->sin_port = htons (conf->port); |
638 |
sa->sin_addr.s_addr = 0; |
639 |
|
640 |
if (conf->hostname) |
641 |
{ |
642 |
struct hostent *he = gethostbyname (conf->hostname); |
643 |
|
644 |
if (he |
645 |
&& he->h_addrtype == AF_INET && he->h_length == 4 && he->h_addr_list[0]) |
646 |
{ |
647 |
//sa->sin_family = he->h_addrtype; |
648 |
memcpy (&sa->sin_addr, he->h_addr_list[0], 4); |
649 |
} |
650 |
else |
651 |
slog (L_NOTICE, _("unable to resolve host '%s'"), conf->hostname); |
652 |
} |
653 |
} |
654 |
|
655 |
void |
656 |
connection::reset_dstaddr () |
657 |
{ |
658 |
fill_sa (&sa, conf); |
659 |
} |
660 |
|
661 |
void |
662 |
connection::send_ping (SOCKADDR *dsa, u8 pong) |
663 |
{ |
664 |
ping_packet *pkt = new ping_packet; |
665 |
|
666 |
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
667 |
vpn->send_vpn_packet (pkt, dsa, IPTOS_LOWDELAY); |
668 |
|
669 |
delete pkt; |
670 |
} |
671 |
|
672 |
void |
673 |
connection::send_reset (SOCKADDR *dsa) |
674 |
{ |
675 |
if (reset_rate_limiter.can (dsa) && connectmode != conf_node::C_DISABLED) |
676 |
{ |
677 |
config_packet *pkt = new config_packet; |
678 |
|
679 |
pkt->setup (vpn_packet::PT_RESET, conf->id); |
680 |
vpn->send_vpn_packet (pkt, dsa, IPTOS_MINCOST); |
681 |
|
682 |
delete pkt; |
683 |
} |
684 |
} |
685 |
|
686 |
void |
687 |
connection::send_auth_request (SOCKADDR *sa, bool initiate) |
688 |
{ |
689 |
if (!initiate || auth_rate_limiter.can (sa)) |
690 |
{ |
691 |
auth_req_packet *pkt = new auth_req_packet (conf->id, initiate); |
692 |
|
693 |
rsachallenge chg; |
694 |
|
695 |
rsa_cache.gen (pkt->id, chg); |
696 |
|
697 |
if (0 > RSA_public_encrypt (sizeof chg, |
698 |
(unsigned char *)&chg, (unsigned char *)&pkt->encr, |
699 |
conf->rsa_key, RSA_PKCS1_OAEP_PADDING)) |
700 |
fatal ("RSA_public_encrypt error"); |
701 |
|
702 |
slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)sockinfo (sa)); |
703 |
|
704 |
vpn->send_vpn_packet (pkt, sa, IPTOS_RELIABILITY); // rsa is very very costly |
705 |
|
706 |
delete pkt; |
707 |
} |
708 |
} |
709 |
|
710 |
void |
711 |
connection::send_auth_response (SOCKADDR *sa, const rsaid &id, const rsachallenge &chg) |
712 |
{ |
713 |
auth_res_packet *pkt = new auth_res_packet (conf->id); |
714 |
|
715 |
pkt->id = id; |
716 |
|
717 |
rsa_hash (id, chg, pkt->response); |
718 |
|
719 |
pkt->hmac_set (octx); |
720 |
|
721 |
slog (L_TRACE, ">>%d PT_AUTH_RES [%s]", conf->id, (const char *)sockinfo (sa)); |
722 |
|
723 |
vpn->send_vpn_packet (pkt, sa, IPTOS_RELIABILITY); // rsa is very very costly |
724 |
|
725 |
delete pkt; |
726 |
} |
727 |
|
728 |
void |
729 |
connection::establish_connection_cb (tstamp &ts) |
730 |
{ |
731 |
if (ictx || conf == THISNODE |
732 |
|| connectmode == conf_node::C_NEVER |
733 |
|| connectmode == conf_node::C_DISABLED) |
734 |
ts = TSTAMP_CANCEL; |
735 |
else if (ts <= NOW) |
736 |
{ |
737 |
double retry_int = double (retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2)) * 0.6; |
738 |
|
739 |
if (retry_int < 3600 * 8) |
740 |
retry_cnt++; |
741 |
|
742 |
ts = NOW + retry_int; |
743 |
|
744 |
if (conf->hostname) |
745 |
{ |
746 |
reset_dstaddr (); |
747 |
if (sa.sin_addr.s_addr) |
748 |
if (retry_cnt < 4) |
749 |
send_auth_request (&sa, true); |
750 |
else if (auth_rate_limiter.can (&sa)) |
751 |
send_ping (&sa, 0); |
752 |
} |
753 |
else |
754 |
vpn->connect_request (conf->id); |
755 |
} |
756 |
} |
757 |
|
758 |
void |
759 |
connection::reset_connection () |
760 |
{ |
761 |
if (ictx && octx) |
762 |
{ |
763 |
slog (L_INFO, _("%s(%s): connection lost"), |
764 |
conf->nodename, (const char *)sockinfo (sa)); |
765 |
|
766 |
if (::conf.script_node_down) |
767 |
run_script (run_script_cb (this, &connection::script_node_down), false); |
768 |
} |
769 |
|
770 |
delete ictx; ictx = 0; |
771 |
delete octx; octx = 0; |
772 |
|
773 |
sa.sin_port = 0; |
774 |
sa.sin_addr.s_addr = 0; |
775 |
|
776 |
last_activity = 0; |
777 |
|
778 |
rekey.reset (); |
779 |
keepalive.reset (); |
780 |
establish_connection.reset (); |
781 |
} |
782 |
|
783 |
void |
784 |
connection::shutdown () |
785 |
{ |
786 |
if (ictx && octx) |
787 |
send_reset (&sa); |
788 |
|
789 |
reset_connection (); |
790 |
} |
791 |
|
792 |
void |
793 |
connection::rekey_cb (tstamp &ts) |
794 |
{ |
795 |
ts = TSTAMP_CANCEL; |
796 |
|
797 |
reset_connection (); |
798 |
establish_connection (); |
799 |
} |
800 |
|
801 |
void |
802 |
connection::send_data_packet (tap_packet * pkt, bool broadcast) |
803 |
{ |
804 |
vpndata_packet *p = new vpndata_packet; |
805 |
int tos = 0; |
806 |
|
807 |
if (conf->inherit_tos |
808 |
&& (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP |
809 |
&& ((*pkt)[14] & 0xf0) == 0x40) // IPv4 |
810 |
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
811 |
|
812 |
p->setup (this, broadcast ? 0 : conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
813 |
vpn->send_vpn_packet (p, &sa, tos); |
814 |
|
815 |
delete p; |
816 |
|
817 |
if (oseqno > MAX_SEQNO) |
818 |
rekey (); |
819 |
} |
820 |
|
821 |
void |
822 |
connection::inject_data_packet (tap_packet *pkt, bool broadcast) |
823 |
{ |
824 |
if (ictx && octx) |
825 |
send_data_packet (pkt, broadcast); |
826 |
else |
827 |
{ |
828 |
if (!broadcast)//DDDD |
829 |
queue.put (new tap_packet (*pkt)); |
830 |
|
831 |
establish_connection (); |
832 |
} |
833 |
} |
834 |
|
835 |
void |
836 |
connection::recv_vpn_packet (vpn_packet *pkt, SOCKADDR *ssa) |
837 |
{ |
838 |
last_activity = NOW; |
839 |
|
840 |
slog (L_NOISE, "<<%d received packet type %d from %d to %d", |
841 |
conf->id, pkt->typ (), pkt->src (), pkt->dst ()); |
842 |
|
843 |
switch (pkt->typ ()) |
844 |
{ |
845 |
case vpn_packet::PT_PING: |
846 |
// we send pings instead of auth packets after some retries, |
847 |
// so reset the retry counter and establish a conenction |
848 |
// when we receive a pong. |
849 |
if (!ictx && !octx) |
850 |
{ |
851 |
retry_cnt = 0; |
852 |
establish_connection.at = 0; |
853 |
establish_connection (); |
854 |
} |
855 |
else |
856 |
send_ping (ssa, 1); // pong |
857 |
|
858 |
break; |
859 |
|
860 |
case vpn_packet::PT_PONG: |
861 |
break; |
862 |
|
863 |
case vpn_packet::PT_RESET: |
864 |
{ |
865 |
reset_connection (); |
866 |
|
867 |
config_packet *p = (config_packet *) pkt; |
868 |
|
869 |
if (!p->chk_config ()) |
870 |
{ |
871 |
slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"), |
872 |
conf->nodename, (const char *)sockinfo (ssa)); |
873 |
connectmode = conf_node::C_DISABLED; |
874 |
} |
875 |
else if (connectmode == conf_node::C_ALWAYS) |
876 |
establish_connection (); |
877 |
} |
878 |
break; |
879 |
|
880 |
case vpn_packet::PT_AUTH_REQ: |
881 |
if (auth_rate_limiter.can (ssa)) |
882 |
{ |
883 |
auth_req_packet *p = (auth_req_packet *) pkt; |
884 |
|
885 |
slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate); |
886 |
|
887 |
if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) |
888 |
{ |
889 |
if (p->prot_minor != PROTOCOL_MINOR) |
890 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
891 |
conf->nodename, (const char *)sockinfo (ssa), |
892 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
893 |
|
894 |
if (p->initiate) |
895 |
send_auth_request (ssa, false); |
896 |
|
897 |
rsachallenge k; |
898 |
|
899 |
if (0 > RSA_private_decrypt (sizeof (p->encr), |
900 |
(unsigned char *)&p->encr, (unsigned char *)&k, |
901 |
::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
902 |
slog (L_ERR, _("%s(%s): challenge illegal or corrupted"), |
903 |
conf->nodename, (const char *)sockinfo (ssa)); |
904 |
else |
905 |
{ |
906 |
retry_cnt = 0; |
907 |
establish_connection.set (NOW + 8); //? ;) |
908 |
keepalive.reset (); |
909 |
rekey.reset (); |
910 |
|
911 |
delete ictx; |
912 |
ictx = 0; |
913 |
|
914 |
delete octx; |
915 |
|
916 |
octx = new crypto_ctx (k, 1); |
917 |
oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; |
918 |
|
919 |
send_auth_response (ssa, p->id, k); |
920 |
|
921 |
break; |
922 |
} |
923 |
} |
924 |
|
925 |
send_reset (ssa); |
926 |
} |
927 |
|
928 |
break; |
929 |
|
930 |
case vpn_packet::PT_AUTH_RES: |
931 |
{ |
932 |
auth_res_packet *p = (auth_res_packet *) pkt; |
933 |
|
934 |
slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id); |
935 |
|
936 |
if (p->chk_config ()) |
937 |
{ |
938 |
if (p->prot_minor != PROTOCOL_MINOR) |
939 |
slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
940 |
conf->nodename, (const char *)sockinfo (ssa), |
941 |
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
942 |
|
943 |
rsachallenge chg; |
944 |
|
945 |
if (!rsa_cache.find (p->id, chg)) |
946 |
slog (L_ERR, _("%s(%s): unrequested auth response"), |
947 |
conf->nodename, (const char *)sockinfo (ssa)); |
948 |
else |
949 |
{ |
950 |
crypto_ctx *cctx = new crypto_ctx (chg, 0); |
951 |
|
952 |
if (!p->hmac_chk (cctx)) |
953 |
slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" |
954 |
"could be an attack, or just corruption or an synchronization error"), |
955 |
conf->nodename, (const char *)sockinfo (ssa)); |
956 |
else |
957 |
{ |
958 |
rsaresponse h; |
959 |
|
960 |
rsa_hash (p->id, chg, h); |
961 |
|
962 |
if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) |
963 |
{ |
964 |
prot_minor = p->prot_minor; |
965 |
|
966 |
delete ictx; ictx = cctx; |
967 |
|
968 |
iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid |
969 |
|
970 |
sa = *ssa; |
971 |
|
972 |
rekey.set (NOW + ::conf.rekey); |
973 |
keepalive.set (NOW + ::conf.keepalive); |
974 |
|
975 |
// send queued packets |
976 |
while (tap_packet *p = queue.get ()) |
977 |
{ |
978 |
send_data_packet (p); |
979 |
delete p; |
980 |
} |
981 |
|
982 |
connectmode = conf->connectmode; |
983 |
|
984 |
slog (L_INFO, _("%s(%s): connection established, protocol version %d:%d"), |
985 |
conf->nodename, (const char *)sockinfo (ssa), |
986 |
p->prot_major, p->prot_minor); |
987 |
|
988 |
if (::conf.script_node_up) |
989 |
run_script (run_script_cb (this, &connection::script_node_up), false); |
990 |
|
991 |
break; |
992 |
} |
993 |
else |
994 |
slog (L_ERR, _("%s(%s): sent and received challenge do not match"), |
995 |
conf->nodename, (const char *)sockinfo (ssa)); |
996 |
} |
997 |
|
998 |
delete cctx; |
999 |
} |
1000 |
} |
1001 |
} |
1002 |
|
1003 |
send_reset (ssa); |
1004 |
break; |
1005 |
|
1006 |
case vpn_packet::PT_DATA_COMPRESSED: |
1007 |
#if !ENABLE_COMPRESSION |
1008 |
send_reset (ssa); |
1009 |
break; |
1010 |
#endif |
1011 |
|
1012 |
case vpn_packet::PT_DATA_UNCOMPRESSED: |
1013 |
|
1014 |
if (ictx && octx) |
1015 |
{ |
1016 |
vpndata_packet *p = (vpndata_packet *)pkt; |
1017 |
|
1018 |
if (*ssa == sa) |
1019 |
{ |
1020 |
if (!p->hmac_chk (ictx)) |
1021 |
slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" |
1022 |
"could be an attack, or just corruption or an synchronization error"), |
1023 |
conf->nodename, (const char *)sockinfo (ssa)); |
1024 |
else |
1025 |
{ |
1026 |
u32 seqno; |
1027 |
tap_packet *d = p->unpack (this, seqno); |
1028 |
|
1029 |
if (iseqno.recv_ok (seqno)) |
1030 |
{ |
1031 |
vpn->tap->send (d); |
1032 |
|
1033 |
if (p->dst () == 0) // re-broadcast |
1034 |
for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i) |
1035 |
{ |
1036 |
connection *c = *i; |
1037 |
|
1038 |
if (c->conf != THISNODE && c->conf != conf) |
1039 |
c->inject_data_packet (d); |
1040 |
} |
1041 |
|
1042 |
delete d; |
1043 |
|
1044 |
break; |
1045 |
} |
1046 |
} |
1047 |
} |
1048 |
else |
1049 |
slog (L_ERR, _("received data packet from unknown source %s"), (const char *)sockinfo (ssa));//D |
1050 |
} |
1051 |
|
1052 |
send_reset (ssa); |
1053 |
break; |
1054 |
|
1055 |
case vpn_packet::PT_CONNECT_REQ: |
1056 |
if (ictx && octx && *ssa == sa && pkt->hmac_chk (ictx)) |
1057 |
{ |
1058 |
connect_req_packet *p = (connect_req_packet *) pkt; |
1059 |
|
1060 |
assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything |
1061 |
|
1062 |
connection *c = vpn->conns[p->id - 1]; |
1063 |
|
1064 |
slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n", |
1065 |
conf->id, p->id, c->ictx && c->octx); |
1066 |
|
1067 |
if (c->ictx && c->octx) |
1068 |
{ |
1069 |
// send connect_info packets to both sides, in case one is |
1070 |
// behind a nat firewall (or both ;) |
1071 |
{ |
1072 |
sockinfo si(sa); |
1073 |
|
1074 |
slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", |
1075 |
c->conf->id, conf->id, (const char *)si); |
1076 |
|
1077 |
connect_info_packet *r = new connect_info_packet (c->conf->id, conf->id, si); |
1078 |
|
1079 |
r->hmac_set (c->octx); |
1080 |
vpn->send_vpn_packet (r, &c->sa); |
1081 |
|
1082 |
delete r; |
1083 |
} |
1084 |
|
1085 |
{ |
1086 |
sockinfo si(c->sa); |
1087 |
|
1088 |
slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", |
1089 |
conf->id, c->conf->id, (const char *)si); |
1090 |
|
1091 |
connect_info_packet *r = new connect_info_packet (conf->id, c->conf->id, si); |
1092 |
|
1093 |
r->hmac_set (octx); |
1094 |
vpn->send_vpn_packet (r, &sa); |
1095 |
|
1096 |
delete r; |
1097 |
} |
1098 |
} |
1099 |
} |
1100 |
|
1101 |
break; |
1102 |
|
1103 |
case vpn_packet::PT_CONNECT_INFO: |
1104 |
if (ictx && octx && *ssa == sa && pkt->hmac_chk (ictx)) |
1105 |
{ |
1106 |
connect_info_packet *p = (connect_info_packet *) pkt; |
1107 |
|
1108 |
assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything |
1109 |
|
1110 |
connection *c = vpn->conns[p->id - 1]; |
1111 |
|
1112 |
slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)", |
1113 |
conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx); |
1114 |
|
1115 |
c->send_auth_request (p->si.sa (), true); |
1116 |
} |
1117 |
|
1118 |
break; |
1119 |
|
1120 |
default: |
1121 |
send_reset (ssa); |
1122 |
break; |
1123 |
|
1124 |
} |
1125 |
} |
1126 |
|
1127 |
void connection::keepalive_cb (tstamp &ts) |
1128 |
{ |
1129 |
if (NOW >= last_activity + ::conf.keepalive + 30) |
1130 |
{ |
1131 |
reset_connection (); |
1132 |
establish_connection (); |
1133 |
} |
1134 |
else if (NOW < last_activity + ::conf.keepalive) |
1135 |
ts = last_activity + ::conf.keepalive; |
1136 |
else if (conf->connectmode != conf_node::C_ONDEMAND |
1137 |
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
1138 |
{ |
1139 |
send_ping (&sa); |
1140 |
ts = NOW + 5; |
1141 |
} |
1142 |
else |
1143 |
reset_connection (); |
1144 |
|
1145 |
} |
1146 |
|
1147 |
void connection::connect_request (int id) |
1148 |
{ |
1149 |
connect_req_packet *p = new connect_req_packet (conf->id, id); |
1150 |
|
1151 |
slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", id, conf->id); |
1152 |
p->hmac_set (octx); |
1153 |
vpn->send_vpn_packet (p, &sa); |
1154 |
|
1155 |
delete p; |
1156 |
} |
1157 |
|
1158 |
void connection::script_node () |
1159 |
{ |
1160 |
vpn->script_if_up (0); |
1161 |
|
1162 |
char *env; |
1163 |
asprintf (&env, "DESTID=%d", conf->id); |
1164 |
putenv (env); |
1165 |
asprintf (&env, "DESTNODE=%s", conf->nodename); |
1166 |
putenv (env); |
1167 |
asprintf (&env, "DESTIP=%s", inet_ntoa (sa.sin_addr)); |
1168 |
putenv (env); |
1169 |
asprintf (&env, "DESTPORT=%d", ntohs (sa.sin_port)); |
1170 |
putenv (env); |
1171 |
} |
1172 |
|
1173 |
const char *connection::script_node_up (int) |
1174 |
{ |
1175 |
script_node (); |
1176 |
|
1177 |
putenv ("STATE=up"); |
1178 |
|
1179 |
return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; |
1180 |
} |
1181 |
|
1182 |
const char *connection::script_node_down (int) |
1183 |
{ |
1184 |
script_node (); |
1185 |
|
1186 |
putenv ("STATE=down"); |
1187 |
|
1188 |
return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; |
1189 |
} |
1190 |
|
1191 |
connection::connection(struct vpn *vpn_) |
1192 |
: vpn(vpn_) |
1193 |
, rekey (this, &connection::rekey_cb) |
1194 |
, keepalive (this, &connection::keepalive_cb) |
1195 |
, establish_connection (this, &connection::establish_connection_cb) |
1196 |
{ |
1197 |
octx = ictx = 0; |
1198 |
retry_cnt = 0; |
1199 |
|
1200 |
connectmode = conf_node::C_ALWAYS; // initial setting |
1201 |
reset_connection (); |
1202 |
} |
1203 |
|
1204 |
connection::~connection () |
1205 |
{ |
1206 |
shutdown (); |
1207 |
} |
1208 |
|
1209 |
///////////////////////////////////////////////////////////////////////////// |
1210 |
|
1211 |
const char *vpn::script_if_up (int) |
1212 |
{ |
1213 |
// the tunnel device mtu should be the physical mtu - overhead |
1214 |
// the tricky part is rounding to the cipher key blocksize |
1215 |
int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - MAX_OVERHEAD; |
1216 |
mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
1217 |
mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round |
1218 |
mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
1219 |
|
1220 |
char *env; |
1221 |
asprintf (&env, "CONFBASE=%s", confbase); |
1222 |
putenv (env); |
1223 |
asprintf (&env, "NODENAME=%s", THISNODE->nodename); |
1224 |
putenv (env); |
1225 |
asprintf (&env, "NODEID=%d", THISNODE->id); |
1226 |
putenv (env); |
1227 |
asprintf (&env, "IFNAME=%s", tap->interface ()); |
1228 |
putenv (env); |
1229 |
asprintf (&env, "MTU=%d", mtu); |
1230 |
putenv (env); |
1231 |
asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x", |
1232 |
0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8, |
1233 |
THISNODE->id & 0xff); |
1234 |
putenv (env); |
1235 |
|
1236 |
return ::conf.script_if_up ? ::conf.script_if_up : "if-up"; |
1237 |
} |
1238 |
|
1239 |
int |
1240 |
vpn::setup (void) |
1241 |
{ |
1242 |
struct sockaddr_in sa; |
1243 |
|
1244 |
socket_fd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
1245 |
if (socket_fd < 0) |
1246 |
return -1; |
1247 |
|
1248 |
fill_sa (&sa, THISNODE); |
1249 |
|
1250 |
if (bind (socket_fd, (sockaddr *)&sa, sizeof (sa))) |
1251 |
{ |
1252 |
slog (L_ERR, _("can't bind to %s: %s"), (const char *)sockinfo(sa), strerror (errno)); |
1253 |
exit (1); |
1254 |
} |
1255 |
|
1256 |
#ifdef IP_MTU_DISCOVER |
1257 |
// this I really consider a linux bug. I am neither connected |
1258 |
// nor do I fragment myself. Linux still sets DF and doesn't |
1259 |
// fragment for me sometimes. |
1260 |
{ |
1261 |
int oval = IP_PMTUDISC_DONT; |
1262 |
setsockopt (socket_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
1263 |
} |
1264 |
#endif |
1265 |
{ |
1266 |
int oval = 1; |
1267 |
setsockopt (socket_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
1268 |
} |
1269 |
|
1270 |
udp_ev_watcher.start (socket_fd, POLLIN); |
1271 |
|
1272 |
tap = new tap_device (); |
1273 |
if (!tap) //D this, of course, never catches |
1274 |
{ |
1275 |
slog (L_ERR, _("cannot create network interface '%s'"), conf.ifname); |
1276 |
exit (1); |
1277 |
} |
1278 |
|
1279 |
run_script (run_script_cb (this, &vpn::script_if_up), true); |
1280 |
|
1281 |
vpn_ev_watcher.start (tap->fd, POLLIN); |
1282 |
|
1283 |
reconnect_all (); |
1284 |
|
1285 |
return 0; |
1286 |
} |
1287 |
|
1288 |
void |
1289 |
vpn::send_vpn_packet (vpn_packet *pkt, SOCKADDR *sa, int tos) |
1290 |
{ |
1291 |
setsockopt (socket_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
1292 |
sendto (socket_fd, &((*pkt)[0]), pkt->len, 0, (sockaddr *)sa, sizeof (*sa)); |
1293 |
} |
1294 |
|
1295 |
void |
1296 |
vpn::shutdown_all () |
1297 |
{ |
1298 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1299 |
(*c)->shutdown (); |
1300 |
} |
1301 |
|
1302 |
void |
1303 |
vpn::reconnect_all () |
1304 |
{ |
1305 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1306 |
delete *c; |
1307 |
|
1308 |
conns.clear (); |
1309 |
|
1310 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); |
1311 |
i != conf.nodes.end (); ++i) |
1312 |
{ |
1313 |
connection *conn = new connection (this); |
1314 |
|
1315 |
conn->conf = *i; |
1316 |
conns.push_back (conn); |
1317 |
|
1318 |
conn->establish_connection (); |
1319 |
} |
1320 |
} |
1321 |
|
1322 |
connection *vpn::find_router () |
1323 |
{ |
1324 |
u32 prio = 0; |
1325 |
connection *router = 0; |
1326 |
|
1327 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
1328 |
{ |
1329 |
connection *c = *i; |
1330 |
|
1331 |
if (c->conf->routerprio > prio |
1332 |
&& c->connectmode == conf_node::C_ALWAYS |
1333 |
&& c->conf != THISNODE |
1334 |
&& c->ictx && c->octx) |
1335 |
{ |
1336 |
prio = c->conf->routerprio; |
1337 |
router = c; |
1338 |
} |
1339 |
} |
1340 |
|
1341 |
return router; |
1342 |
} |
1343 |
|
1344 |
void vpn::connect_request (int id) |
1345 |
{ |
1346 |
connection *c = find_router (); |
1347 |
|
1348 |
if (c) |
1349 |
c->connect_request (id); |
1350 |
//else // does not work, because all others must connect to the same router |
1351 |
// // no router found, aggressively connect to all routers |
1352 |
// for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
1353 |
// if ((*i)->conf->routerprio) |
1354 |
// (*i)->establish_connection (); |
1355 |
} |
1356 |
|
1357 |
void |
1358 |
vpn::udp_ev (short revents) |
1359 |
{ |
1360 |
if (revents & (POLLIN | POLLERR)) |
1361 |
{ |
1362 |
vpn_packet *pkt = new vpn_packet; |
1363 |
struct sockaddr_in sa; |
1364 |
socklen_t sa_len = sizeof (sa); |
1365 |
int len; |
1366 |
|
1367 |
len = recvfrom (socket_fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
1368 |
|
1369 |
if (len > 0) |
1370 |
{ |
1371 |
pkt->len = len; |
1372 |
|
1373 |
unsigned int src = pkt->src (); |
1374 |
unsigned int dst = pkt->dst (); |
1375 |
|
1376 |
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d"), |
1377 |
(const char *)sockinfo (sa), pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
1378 |
|
1379 |
if (dst > conns.size () || pkt->typ () >= vpn_packet::PT_MAX) |
1380 |
slog (L_WARN, _("<<? received CORRUPTED packet type %d from %d to %d"), |
1381 |
pkt->typ (), pkt->src (), pkt->dst ()); |
1382 |
else if (dst == 0 && !THISNODE->routerprio) |
1383 |
slog (L_WARN, _("<<%d received broadcast, but we are no router"), dst); |
1384 |
else if (dst != 0 && dst != THISNODE->id) |
1385 |
slog (L_WARN, |
1386 |
_("received frame for node %d ('%s') from %s, but this is node %d ('%s')"), |
1387 |
dst, conns[dst - 1]->conf->nodename, |
1388 |
(const char *)sockinfo (sa), |
1389 |
THISNODE->id, THISNODE->nodename); |
1390 |
else if (src == 0 || src > conns.size ()) |
1391 |
slog (L_WARN, _("received frame from unknown node %d (%s)"), src, (const char *)sockinfo (sa)); |
1392 |
else |
1393 |
conns[src - 1]->recv_vpn_packet (pkt, &sa); |
1394 |
} |
1395 |
else |
1396 |
{ |
1397 |
// probably ECONNRESET or somesuch |
1398 |
slog (L_DEBUG, _("%s: %s"), (const char *)sockinfo(sa), strerror (errno)); |
1399 |
} |
1400 |
|
1401 |
delete pkt; |
1402 |
} |
1403 |
else if (revents & POLLHUP) |
1404 |
{ |
1405 |
// this cannot ;) happen on udp sockets |
1406 |
slog (L_ERR, _("FATAL: POLLHUP on socket fd, terminating.")); |
1407 |
exit (1); |
1408 |
} |
1409 |
else |
1410 |
{ |
1411 |
slog (L_ERR, |
1412 |
_("FATAL: unknown revents %08x in socket, terminating\n"), |
1413 |
revents); |
1414 |
exit (1); |
1415 |
} |
1416 |
} |
1417 |
|
1418 |
void |
1419 |
vpn::vpn_ev (short revents) |
1420 |
{ |
1421 |
if (revents & POLLIN) |
1422 |
{ |
1423 |
/* process data */ |
1424 |
tap_packet *pkt; |
1425 |
|
1426 |
pkt = tap->recv (); |
1427 |
|
1428 |
int dst = mac2id (pkt->dst); |
1429 |
int src = mac2id (pkt->src); |
1430 |
|
1431 |
if (src != THISNODE->id) |
1432 |
{ |
1433 |
slog (L_ERR, _("FATAL: tap packet not originating on current node received, terminating.")); |
1434 |
exit (1); |
1435 |
} |
1436 |
|
1437 |
if (dst == THISNODE->id) |
1438 |
{ |
1439 |
slog (L_ERR, _("FATAL: tap packet destined for current node received, terminating.")); |
1440 |
exit (1); |
1441 |
} |
1442 |
|
1443 |
if (dst > conns.size ()) |
1444 |
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
1445 |
else |
1446 |
{ |
1447 |
if (dst) |
1448 |
{ |
1449 |
// unicast |
1450 |
if (dst != THISNODE->id) |
1451 |
conns[dst - 1]->inject_data_packet (pkt); |
1452 |
} |
1453 |
else |
1454 |
{ |
1455 |
// broadcast, first check router, then self, then english |
1456 |
connection *router = find_router (); |
1457 |
|
1458 |
if (router) |
1459 |
router->inject_data_packet (pkt, true); |
1460 |
else |
1461 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1462 |
if ((*c)->conf != THISNODE) |
1463 |
(*c)->inject_data_packet (pkt); |
1464 |
} |
1465 |
} |
1466 |
|
1467 |
delete pkt; |
1468 |
} |
1469 |
else if (revents & (POLLHUP | POLLERR)) |
1470 |
{ |
1471 |
slog (L_ERR, _("FATAL: POLLHUP or POLLERR on network device fd, terminating.")); |
1472 |
exit (1); |
1473 |
} |
1474 |
else |
1475 |
abort (); |
1476 |
} |
1477 |
|
1478 |
void |
1479 |
vpn::event_cb (tstamp &ts) |
1480 |
{ |
1481 |
if (events) |
1482 |
{ |
1483 |
if (events & EVENT_SHUTDOWN) |
1484 |
{ |
1485 |
shutdown_all (); |
1486 |
|
1487 |
remove_pid (pidfilename); |
1488 |
|
1489 |
slog (L_INFO, _("vped terminating")); |
1490 |
|
1491 |
exit (0); |
1492 |
} |
1493 |
|
1494 |
if (events & EVENT_RECONNECT) |
1495 |
reconnect_all (); |
1496 |
|
1497 |
events = 0; |
1498 |
} |
1499 |
|
1500 |
ts = TSTAMP_CANCEL; |
1501 |
} |
1502 |
|
1503 |
vpn::vpn (void) |
1504 |
: udp_ev_watcher (this, &vpn::udp_ev) |
1505 |
, vpn_ev_watcher (this, &vpn::vpn_ev) |
1506 |
, event (this, &vpn::event_cb) |
1507 |
{ |
1508 |
} |
1509 |
|
1510 |
vpn::~vpn () |
1511 |
{ |
1512 |
} |
1513 |
|