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pcg |
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/* |
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protocol.C -- handle the protocol, encryption, handshaking etc. |
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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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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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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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#include "config.h" |
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#include <cstdlib> |
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#include <cstring> |
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#include <cstdio> |
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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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#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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extern "C" { |
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# include "lzf/lzf.h" |
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} |
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#include "gettext.h" |
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#include "pidfile.h" |
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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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#if !HAVE_RAND_PSEUDO_BYTES |
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# define RAND_pseudo_bytes RAND_bytes |
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#endif |
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static time_t next_timecheck; |
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#define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic |
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static const rsachallenge & |
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challenge_bytes () |
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{ |
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static rsachallenge challenge; |
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static time_t challenge_ttl; // time this challenge needs to be recreated |
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if (now > challenge_ttl) |
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{ |
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RAND_bytes ((unsigned char *)&challenge, sizeof (challenge)); |
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challenge_ttl = now + CHALLENGE_TTL; |
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} |
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return challenge; |
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} |
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// run a script. yes, it's a template function. yes, c++ |
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// is not a functional language. yes, this suxx. |
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template<class owner> |
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static void |
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run_script (owner *obj, const char *(owner::*setup)(), bool wait) |
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{ |
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int pid; |
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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, (obj->*setup) ()); |
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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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// xor the socket address into the challenge to ensure different challenges |
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// per host. we could rely on the OAEP padding, but this doesn't hurt. |
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void |
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xor_sa (rsachallenge &k, SOCKADDR *sa) |
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{ |
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((u32 *) k)[(CHG_CIPHER_KEY + 0) / 4] ^= sa->sin_addr.s_addr; |
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((u16 *) k)[(CHG_CIPHER_KEY + 4) / 2] ^= sa->sin_port; |
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((u32 *) k)[(CHG_HMAC_KEY + 0) / 4] ^= sa->sin_addr.s_addr; |
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((u16 *) k)[(CHG_HMAC_KEY + 4) / 2] ^= sa->sin_port; |
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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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crypto_ctx (rsachallenge &challenge, int enc); |
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~crypto_ctx (); |
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}; |
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crypto_ctx::crypto_ctx (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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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 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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static unsigned char hmac_digest[EVP_MAX_MD_SIZE]; |
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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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void hmac_set (crypto_ctx * ctx); |
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bool hmac_chk (crypto_ctx * ctx); |
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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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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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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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memcpy (hmac, hmac_digest, HMACLENGTH); |
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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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return !memcmp (hmac, hmac_digest, HMACLENGTH); |
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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, // authentification |
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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_REKEY, // rekeying (not yet implemented) |
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PT_MAX |
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}; |
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u8 type; |
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u8 srcdst, src1, dst1; |
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void set_hdr (ptype type, unsigned int dst); |
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unsigned int src () |
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{ |
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return src1 | ((srcdst >> 4) << 8); |
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} |
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unsigned int dst () |
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{ |
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return dst1 | ((srcdst & 0xf) << 8); |
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} |
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ptype typ () |
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{ |
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return (ptype) type; |
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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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int src = THISNODE->id; |
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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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#define MAXVPNDATA (MAX_MTU - 6 - 6) |
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#define DATAHDR (sizeof (u32) + RAND_SIZE) |
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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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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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const u32 data_hdr_size () const |
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{ |
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return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; |
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} |
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}; |
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void |
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vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) |
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{ |
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EVP_CIPHER_CTX *cctx = &conn->octx->cctx; |
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int outl = 0, outl2; |
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ptype type = PT_DATA_UNCOMPRESSED; |
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#if ENABLE_COMPRESSION |
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u8 cdata[MAX_MTU]; |
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u32 cl; |
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cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); |
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if (cl) |
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{ |
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//printf ("compressed packet, %d => %d\n", l, cl);//D |
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type = PT_DATA_COMPRESSED; |
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d = cdata; |
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l = cl + 2; |
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d[0] = cl >> 8; |
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d[1] = cl; |
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} |
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#endif |
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EVP_EncryptInit_ex (cctx, 0, 0, 0, 0); |
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#if RAND_SIZE |
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struct { |
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u8 rnd[RAND_SIZE]; |
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u32 seqno; |
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} datahdr; |
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datahdr.seqno = seqno; |
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RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE); |
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EVP_EncryptUpdate (cctx, |
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(unsigned char *) data + outl, &outl2, |
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(unsigned char *) &datahdr, DATAHDR); |
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outl += outl2; |
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#else |
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EVP_EncryptUpdate (cctx, |
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(unsigned char *) data + outl, &outl2, |
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(unsigned char *) &seqno, DATAHDR); |
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outl += outl2; |
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#endif |
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EVP_EncryptUpdate (cctx, |
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(unsigned char *) data + outl, &outl2, |
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(unsigned char *) d, l); |
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outl += outl2; |
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EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2); |
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outl += outl2; |
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len = outl + data_hdr_size (); |
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set_hdr (type, dst); |
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hmac_set (conn->octx); |
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} |
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tap_packet * |
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vpndata_packet::unpack (connection *conn, u32 &seqno) |
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{ |
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EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; |
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int outl = 0, outl2; |
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tap_packet *p = new tap_packet; |
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u8 *d; |
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u32 l = len - data_hdr_size (); |
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EVP_DecryptInit_ex (cctx, 0, 0, 0, 0); |
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#if ENABLE_COMPRESSION |
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u8 cdata[MAX_MTU]; |
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if (type == PT_DATA_COMPRESSED) |
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d = cdata; |
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else |
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#endif |
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d = &(*p)[6 + 6 - DATAHDR]; |
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/* this overwrites part of the src mac, but we fix that later */ |
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EVP_DecryptUpdate (cctx, |
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d, &outl2, |
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(unsigned char *)&data, len - data_hdr_size ()); |
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outl += outl2; |
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EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2); |
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outl += outl2; |
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seqno = *(u32 *)(d + RAND_SIZE); |
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335 |
pcg |
1.2 |
id2mac (dst () ? dst() : THISNODE->id, p->dst); |
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id2mac (src (), p->src); |
337 |
pcg |
1.1 |
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#if ENABLE_COMPRESSION |
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if (type == PT_DATA_COMPRESSED) |
340 |
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{ |
341 |
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u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; |
342 |
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p->len = lzf_decompress (d + DATAHDR + 2, cl, &(*p)[6 + 6], MAX_MTU) + 6 + 6; |
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//printf ("decompressxed %d(%d) => %d\n", cl, len - data_hdr_size (), p->len);//D |
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} |
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else |
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p->len = outl + (6 + 6 - DATAHDR); |
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#endif |
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return p; |
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} |
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struct ping_packet : vpn_packet |
353 |
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{ |
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void setup (int dst, ptype type) |
355 |
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{ |
356 |
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set_hdr (type, dst); |
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len = sizeof (*this) - sizeof (net_packet); |
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} |
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}; |
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struct config_packet : vpn_packet |
362 |
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{ |
363 |
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// actually, hmaclen cannot be checked because the hmac |
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// field comes before this data, so peers with other |
365 |
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// hmacs simply will not work. |
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u8 prot_major, prot_minor, randsize, hmaclen; |
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u8 flags, challengelen, pad2, pad3; |
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u32 cipher_nid; |
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u32 digest_nid; |
370 |
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371 |
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const u8 curflags () const |
372 |
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{ |
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return 0x80 |
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| (ENABLE_COMPRESSION ? 0x01 : 0x00) |
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| (ENABLE_TRUST ? 0x02 : 0x00); |
376 |
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} |
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378 |
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void setup (ptype type, int dst) |
379 |
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{ |
380 |
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prot_major = PROTOCOL_MAJOR; |
381 |
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prot_minor = PROTOCOL_MINOR; |
382 |
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randsize = RAND_SIZE; |
383 |
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hmaclen = HMACLENGTH; |
384 |
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flags = curflags (); |
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challengelen = sizeof (rsachallenge); |
386 |
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387 |
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cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); |
388 |
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digest_nid = htonl (EVP_MD_type (DIGEST)); |
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390 |
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len = sizeof (*this) - sizeof (net_packet); |
391 |
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set_hdr (type, dst); |
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} |
393 |
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394 |
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bool chk_config () |
395 |
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{ |
396 |
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return prot_major == PROTOCOL_MAJOR |
397 |
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&& randsize == RAND_SIZE |
398 |
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&& hmaclen == HMACLENGTH |
399 |
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&& flags == curflags () |
400 |
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|
&& challengelen == sizeof (rsachallenge) |
401 |
|
|
&& cipher_nid == htonl (EVP_CIPHER_nid (CIPHER)) |
402 |
|
|
&& digest_nid == htonl (EVP_MD_type (DIGEST)); |
403 |
|
|
} |
404 |
|
|
}; |
405 |
|
|
|
406 |
|
|
struct auth_packet : config_packet |
407 |
|
|
{ |
408 |
|
|
char magic[8]; |
409 |
|
|
u8 subtype; |
410 |
|
|
u8 pad1, pad2; |
411 |
|
|
rsaencrdata challenge; |
412 |
|
|
|
413 |
|
|
auth_packet (int dst, auth_subtype stype) |
414 |
|
|
{ |
415 |
|
|
config_packet::setup (PT_AUTH, dst); |
416 |
|
|
subtype = stype; |
417 |
|
|
len = sizeof (*this) - sizeof (net_packet); |
418 |
|
|
strncpy (magic, MAGIC, 8); |
419 |
|
|
} |
420 |
|
|
}; |
421 |
|
|
|
422 |
|
|
struct connect_req_packet : vpn_packet |
423 |
|
|
{ |
424 |
|
|
u8 id; |
425 |
|
|
u8 pad1, pad2, pad3; |
426 |
|
|
|
427 |
|
|
connect_req_packet (int dst, int id) |
428 |
|
|
{ |
429 |
|
|
this->id = id; |
430 |
|
|
set_hdr (PT_CONNECT_REQ, dst); |
431 |
|
|
len = sizeof (*this) - sizeof (net_packet); |
432 |
|
|
} |
433 |
|
|
}; |
434 |
|
|
|
435 |
|
|
struct connect_info_packet : vpn_packet |
436 |
|
|
{ |
437 |
|
|
u8 id; |
438 |
|
|
u8 pad1, pad2, pad3; |
439 |
|
|
sockinfo si; |
440 |
|
|
|
441 |
|
|
connect_info_packet (int dst, int id, sockinfo &si) |
442 |
|
|
{ |
443 |
|
|
this->id = id; |
444 |
|
|
this->si = si; |
445 |
|
|
set_hdr (PT_CONNECT_INFO, dst); |
446 |
|
|
len = sizeof (*this) - sizeof (net_packet); |
447 |
|
|
} |
448 |
|
|
}; |
449 |
|
|
|
450 |
|
|
///////////////////////////////////////////////////////////////////////////// |
451 |
|
|
|
452 |
|
|
void |
453 |
|
|
fill_sa (SOCKADDR *sa, conf_node *conf) |
454 |
|
|
{ |
455 |
|
|
sa->sin_family = AF_INET; |
456 |
|
|
sa->sin_port = htons (conf->port); |
457 |
|
|
sa->sin_addr.s_addr = 0; |
458 |
|
|
|
459 |
|
|
if (conf->hostname) |
460 |
|
|
{ |
461 |
|
|
struct hostent *he = gethostbyname (conf->hostname); |
462 |
|
|
|
463 |
|
|
if (he |
464 |
|
|
&& he->h_addrtype == AF_INET && he->h_length == 4 && he->h_addr_list[0]) |
465 |
|
|
{ |
466 |
|
|
//sa->sin_family = he->h_addrtype; |
467 |
|
|
memcpy (&sa->sin_addr, he->h_addr_list[0], 4); |
468 |
|
|
} |
469 |
|
|
else |
470 |
|
|
slog (L_NOTICE, _("unable to resolve host '%s'"), conf->hostname); |
471 |
|
|
} |
472 |
|
|
} |
473 |
|
|
|
474 |
|
|
void |
475 |
|
|
connection::reset_dstaddr () |
476 |
|
|
{ |
477 |
|
|
fill_sa (&sa, conf); |
478 |
|
|
} |
479 |
|
|
|
480 |
|
|
void |
481 |
|
|
connection::send_ping (SOCKADDR *dsa, u8 pong) |
482 |
|
|
{ |
483 |
|
|
ping_packet *pkt = new ping_packet; |
484 |
|
|
|
485 |
|
|
pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
486 |
pcg |
1.6 |
vpn->send_vpn_packet (pkt, dsa, IPTOS_LOWDELAY); |
487 |
pcg |
1.1 |
|
488 |
|
|
delete pkt; |
489 |
|
|
} |
490 |
|
|
|
491 |
|
|
void |
492 |
|
|
connection::send_reset (SOCKADDR *dsa) |
493 |
|
|
{ |
494 |
|
|
static net_rate_limiter limiter(1); |
495 |
|
|
|
496 |
|
|
if (limiter.can (dsa)) |
497 |
|
|
{ |
498 |
|
|
config_packet *pkt = new config_packet; |
499 |
|
|
|
500 |
|
|
pkt->setup (vpn_packet::PT_RESET, conf->id); |
501 |
pcg |
1.6 |
vpn->send_vpn_packet (pkt, dsa, IPTOS_MINCOST); |
502 |
pcg |
1.1 |
|
503 |
|
|
delete pkt; |
504 |
|
|
} |
505 |
|
|
} |
506 |
|
|
|
507 |
|
|
static rsachallenge * |
508 |
|
|
gen_challenge (SOCKADDR *sa) |
509 |
|
|
{ |
510 |
|
|
static rsachallenge k; |
511 |
|
|
|
512 |
|
|
memcpy (&k, &challenge_bytes (), sizeof (k)); |
513 |
|
|
RAND_bytes ((unsigned char *)&k[CHG_SEQNO], sizeof (u32)); |
514 |
|
|
xor_sa (k, sa); |
515 |
|
|
|
516 |
|
|
return &k; |
517 |
|
|
} |
518 |
|
|
|
519 |
|
|
void |
520 |
|
|
connection::send_auth (auth_subtype subtype, SOCKADDR *sa, rsachallenge *k) |
521 |
|
|
{ |
522 |
|
|
static net_rate_limiter limiter(2); |
523 |
|
|
|
524 |
|
|
if (subtype != AUTH_INIT || limiter.can (sa)) |
525 |
|
|
{ |
526 |
|
|
auth_packet *pkt = new auth_packet (conf->id, subtype); |
527 |
|
|
|
528 |
|
|
//printf ("send auth_packet subtype %d\n", subtype);//D |
529 |
|
|
|
530 |
|
|
if (!k) |
531 |
|
|
k = gen_challenge (sa); |
532 |
|
|
|
533 |
|
|
#if ENABLE_TRUST |
534 |
|
|
if (0 > RSA_public_encrypt (sizeof (*k), |
535 |
|
|
(unsigned char *)k, (unsigned char *)&pkt->challenge, |
536 |
|
|
conf->rsa_key, RSA_PKCS1_OAEP_PADDING)) |
537 |
|
|
fatal ("RSA_public_encrypt error"); |
538 |
|
|
#else |
539 |
|
|
# error untrusted mode not yet implemented: programemr does not know how to |
540 |
|
|
rsaencrdata enc; |
541 |
|
|
|
542 |
|
|
if (0 > RSA_private_encrypt (sizeof (*k), |
543 |
|
|
(unsigned char *)k, (unsigned char *)&enc, |
544 |
|
|
::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
545 |
|
|
fatal ("RSA_private_encrypt error"); |
546 |
|
|
|
547 |
|
|
if (0 > RSA_public_encrypt (sizeof (enc), |
548 |
|
|
(unsigned char *)enc, (unsigned char *)&pkt->challenge, |
549 |
|
|
conf->rsa_key, RSA_NO_PADDING)) |
550 |
|
|
fatal ("RSA_public_encrypt error"); |
551 |
|
|
#endif |
552 |
|
|
|
553 |
|
|
slog (L_TRACE, ">>%d PT_AUTH(%d) [%s]", conf->id, subtype, (const char *)sockinfo (sa)); |
554 |
|
|
|
555 |
pcg |
1.6 |
vpn->send_vpn_packet (pkt, sa, IPTOS_RELIABILITY); |
556 |
pcg |
1.1 |
|
557 |
|
|
delete pkt; |
558 |
|
|
} |
559 |
|
|
} |
560 |
|
|
|
561 |
|
|
void |
562 |
|
|
connection::establish_connection () |
563 |
|
|
{ |
564 |
pcg |
1.5 |
if (!ictx && conf != THISNODE && connectmode != conf_node::C_NEVER) |
565 |
pcg |
1.1 |
{ |
566 |
|
|
if (now >= next_retry) |
567 |
|
|
{ |
568 |
|
|
int retry_int = retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2); |
569 |
|
|
|
570 |
|
|
if (retry_cnt < (17 << 2) | 3) |
571 |
|
|
retry_cnt++; |
572 |
|
|
|
573 |
pcg |
1.5 |
if (connectmode == conf_node::C_ONDEMAND |
574 |
pcg |
1.1 |
&& retry_int > ::conf.keepalive) |
575 |
|
|
retry_int = ::conf.keepalive; |
576 |
|
|
|
577 |
|
|
next_retry = now + retry_int; |
578 |
|
|
next_wakeup (next_retry); |
579 |
|
|
|
580 |
|
|
if (conf->hostname) |
581 |
|
|
{ |
582 |
|
|
reset_dstaddr (); |
583 |
|
|
if (sa.sin_addr.s_addr) |
584 |
|
|
if (retry_cnt < 4) |
585 |
|
|
send_auth (AUTH_INIT, &sa); |
586 |
|
|
else |
587 |
|
|
send_ping (&sa, 0); |
588 |
|
|
} |
589 |
|
|
else |
590 |
|
|
vpn->connect_request (conf->id); |
591 |
|
|
} |
592 |
|
|
} |
593 |
|
|
} |
594 |
|
|
|
595 |
|
|
void |
596 |
|
|
connection::reset_connection () |
597 |
|
|
{ |
598 |
|
|
if (ictx && octx) |
599 |
|
|
{ |
600 |
|
|
slog (L_INFO, _("connection to %d (%s) lost"), conf->id, conf->nodename); |
601 |
|
|
|
602 |
|
|
if (::conf.script_node_down) |
603 |
|
|
run_script (this, &connection::script_node_down, false); |
604 |
|
|
} |
605 |
|
|
|
606 |
|
|
delete ictx; |
607 |
|
|
ictx = 0; |
608 |
|
|
|
609 |
|
|
delete octx; |
610 |
|
|
octx = 0; |
611 |
|
|
|
612 |
|
|
sa.sin_port = 0; |
613 |
|
|
sa.sin_addr.s_addr = 0; |
614 |
|
|
|
615 |
|
|
next_retry = 0; |
616 |
|
|
next_rekey = 0; |
617 |
|
|
last_activity = 0; |
618 |
|
|
} |
619 |
|
|
|
620 |
|
|
void |
621 |
|
|
connection::shutdown () |
622 |
|
|
{ |
623 |
|
|
if (ictx && octx) |
624 |
|
|
send_reset (&sa); |
625 |
|
|
|
626 |
|
|
reset_connection (); |
627 |
|
|
} |
628 |
|
|
|
629 |
|
|
void |
630 |
|
|
connection::rekey () |
631 |
|
|
{ |
632 |
|
|
reset_connection (); |
633 |
|
|
establish_connection (); |
634 |
|
|
} |
635 |
|
|
|
636 |
|
|
void |
637 |
|
|
connection::send_data_packet (tap_packet * pkt, bool broadcast) |
638 |
|
|
{ |
639 |
|
|
vpndata_packet *p = new vpndata_packet; |
640 |
pcg |
1.6 |
int tos = 0; |
641 |
|
|
|
642 |
|
|
if (conf->inherit_tos |
643 |
|
|
&& (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP |
644 |
|
|
&& ((*pkt)[14] & 0xf0) == 0x40) // IPv4 |
645 |
|
|
tos = (*pkt)[15] & IPTOS_TOS_MASK; |
646 |
pcg |
1.1 |
|
647 |
|
|
p->setup (this, broadcast ? 0 : conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs |
648 |
pcg |
1.6 |
vpn->send_vpn_packet (p, &sa, tos); |
649 |
pcg |
1.1 |
|
650 |
|
|
delete p; |
651 |
|
|
|
652 |
|
|
if (oseqno > MAX_SEQNO) |
653 |
|
|
rekey (); |
654 |
|
|
} |
655 |
|
|
|
656 |
|
|
void |
657 |
|
|
connection::inject_data_packet (tap_packet *pkt, bool broadcast) |
658 |
|
|
{ |
659 |
|
|
if (ictx && octx) |
660 |
|
|
send_data_packet (pkt, broadcast); |
661 |
|
|
else |
662 |
|
|
{ |
663 |
|
|
if (!broadcast)//DDDD |
664 |
|
|
queue.put (new tap_packet (*pkt)); |
665 |
|
|
|
666 |
|
|
establish_connection (); |
667 |
|
|
} |
668 |
|
|
} |
669 |
|
|
|
670 |
|
|
void |
671 |
|
|
connection::recv_vpn_packet (vpn_packet *pkt, SOCKADDR *ssa) |
672 |
|
|
{ |
673 |
|
|
last_activity = now; |
674 |
|
|
|
675 |
|
|
slog (L_NOISE, "<<%d received packet type %d from %d to %d", |
676 |
|
|
conf->id, pkt->typ (), pkt->src (), pkt->dst ()); |
677 |
|
|
|
678 |
|
|
switch (pkt->typ ()) |
679 |
|
|
{ |
680 |
|
|
case vpn_packet::PT_PING: |
681 |
|
|
send_ping (ssa, 1); // pong |
682 |
|
|
break; |
683 |
|
|
|
684 |
|
|
case vpn_packet::PT_PONG: |
685 |
|
|
// we send pings instead of auth packets after some retries, |
686 |
|
|
// so reset the retry counter and establish a conenction |
687 |
|
|
// when we receive a pong. |
688 |
|
|
if (!ictx && !octx) |
689 |
|
|
{ |
690 |
|
|
retry_cnt = 0; |
691 |
|
|
next_retry = 0; |
692 |
|
|
establish_connection (); |
693 |
|
|
} |
694 |
|
|
|
695 |
|
|
break; |
696 |
|
|
|
697 |
|
|
case vpn_packet::PT_RESET: |
698 |
|
|
{ |
699 |
|
|
reset_connection (); |
700 |
|
|
|
701 |
|
|
config_packet *p = (config_packet *) pkt; |
702 |
|
|
if (p->chk_config ()) |
703 |
pcg |
1.5 |
if (connectmode == conf_node::C_ALWAYS) |
704 |
pcg |
1.1 |
establish_connection (); |
705 |
|
|
|
706 |
|
|
//D slog the protocol mismatch? |
707 |
|
|
} |
708 |
|
|
break; |
709 |
|
|
|
710 |
|
|
case vpn_packet::PT_AUTH: |
711 |
|
|
{ |
712 |
|
|
auth_packet *p = (auth_packet *) pkt; |
713 |
|
|
|
714 |
|
|
slog (L_TRACE, "<<%d PT_AUTH(%d)", conf->id, p->subtype); |
715 |
|
|
|
716 |
|
|
if (p->chk_config () |
717 |
|
|
&& !strncmp (p->magic, MAGIC, 8)) |
718 |
|
|
{ |
719 |
|
|
if (p->prot_minor != PROTOCOL_MINOR) |
720 |
|
|
slog (L_INFO, _("protocol minor version mismatch: ours is %d, %s's is %d."), |
721 |
|
|
PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
722 |
|
|
|
723 |
|
|
if (p->subtype == AUTH_INIT) |
724 |
|
|
send_auth (AUTH_INITREPLY, ssa); |
725 |
|
|
|
726 |
|
|
rsachallenge k; |
727 |
|
|
|
728 |
|
|
#if ENABLE_TRUST |
729 |
|
|
if (0 > RSA_private_decrypt (sizeof (rsaencrdata), |
730 |
|
|
(unsigned char *)&p->challenge, (unsigned char *)&k, |
731 |
|
|
::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) |
732 |
|
|
// continued below |
733 |
|
|
#else |
734 |
|
|
rsaencrdata j; |
735 |
|
|
|
736 |
|
|
if (0 > RSA_private_decrypt (sizeof (rsaencrdata), |
737 |
|
|
(unsigned char *)&p->challenge, (unsigned char *)&j, |
738 |
|
|
::conf.rsa_key, RSA_NO_PADDING)) |
739 |
|
|
fatal ("RSA_private_decrypt error"); |
740 |
|
|
|
741 |
|
|
if (0 > RSA_public_decrypt (sizeof (k), |
742 |
|
|
(unsigned char *)&j, (unsigned char *)&k, |
743 |
|
|
conf->rsa_key, RSA_PKCS1_OAEP_PADDING)) |
744 |
|
|
// continued below |
745 |
|
|
#endif |
746 |
|
|
{ |
747 |
|
|
slog (L_ERR, _("challenge from %s (%s) illegal or corrupted"), |
748 |
|
|
conf->nodename, (const char *)sockinfo (ssa)); |
749 |
|
|
break; |
750 |
|
|
} |
751 |
|
|
|
752 |
|
|
retry_cnt = 0; |
753 |
|
|
next_retry = now + 8; |
754 |
|
|
|
755 |
|
|
switch (p->subtype) |
756 |
|
|
{ |
757 |
|
|
case AUTH_INIT: |
758 |
|
|
case AUTH_INITREPLY: |
759 |
|
|
delete ictx; |
760 |
|
|
ictx = 0; |
761 |
|
|
|
762 |
|
|
delete octx; |
763 |
|
|
|
764 |
|
|
octx = new crypto_ctx (k, 1); |
765 |
|
|
oseqno = *(u32 *)&k[CHG_SEQNO] & 0x7fffffff; |
766 |
|
|
|
767 |
|
|
send_auth (AUTH_REPLY, ssa, &k); |
768 |
|
|
break; |
769 |
|
|
|
770 |
|
|
case AUTH_REPLY: |
771 |
|
|
|
772 |
|
|
if (!memcmp ((u8 *)gen_challenge (ssa) + sizeof (u32), (u8 *)&k + sizeof (u32), |
773 |
|
|
sizeof (rsachallenge) - sizeof (u32))) |
774 |
|
|
{ |
775 |
|
|
delete ictx; |
776 |
|
|
|
777 |
|
|
ictx = new crypto_ctx (k, 0); |
778 |
|
|
iseqno = *(u32 *)&k[CHG_SEQNO] & 0x7fffffff; // at least 2**31 sequence numbers are valid |
779 |
|
|
ismask = 0xffffffff; // initially, all lower sequence numbers are invalid |
780 |
|
|
|
781 |
|
|
sa = *ssa; |
782 |
|
|
|
783 |
|
|
next_rekey = now + ::conf.rekey; |
784 |
|
|
next_wakeup (next_rekey); |
785 |
|
|
|
786 |
|
|
// send queued packets |
787 |
|
|
while (tap_packet *p = queue.get ()) |
788 |
|
|
{ |
789 |
|
|
send_data_packet (p); |
790 |
|
|
delete p; |
791 |
|
|
} |
792 |
|
|
|
793 |
pcg |
1.5 |
connectmode = conf->connectmode; |
794 |
|
|
|
795 |
pcg |
1.1 |
slog (L_INFO, _("connection to %d (%s %s) established"), |
796 |
|
|
conf->id, conf->nodename, (const char *)sockinfo (ssa)); |
797 |
|
|
|
798 |
|
|
if (::conf.script_node_up) |
799 |
|
|
run_script (this, &connection::script_node_up, false); |
800 |
|
|
} |
801 |
|
|
else |
802 |
|
|
slog (L_ERR, _("sent and received challenge do not match with (%s %s))"), |
803 |
|
|
conf->nodename, (const char *)sockinfo (ssa)); |
804 |
|
|
|
805 |
|
|
break; |
806 |
|
|
default: |
807 |
|
|
slog (L_ERR, _("authentification illegal subtype error (%s %s)"), |
808 |
|
|
conf->nodename, (const char *)sockinfo (ssa)); |
809 |
|
|
break; |
810 |
|
|
} |
811 |
|
|
} |
812 |
|
|
else |
813 |
|
|
send_reset (ssa); |
814 |
|
|
|
815 |
|
|
break; |
816 |
|
|
} |
817 |
|
|
|
818 |
|
|
case vpn_packet::PT_DATA_COMPRESSED: |
819 |
|
|
#if !ENABLE_COMPRESSION |
820 |
|
|
send_reset (ssa); |
821 |
|
|
break; |
822 |
|
|
#endif |
823 |
|
|
case vpn_packet::PT_DATA_UNCOMPRESSED: |
824 |
|
|
|
825 |
|
|
if (ictx && octx) |
826 |
|
|
{ |
827 |
|
|
vpndata_packet *p = (vpndata_packet *)pkt; |
828 |
|
|
|
829 |
|
|
if (*ssa == sa) |
830 |
|
|
{ |
831 |
|
|
if (!p->hmac_chk (ictx)) |
832 |
|
|
slog (L_ERR, _("hmac authentication error, received invalid packet\n" |
833 |
|
|
"could be an attack, or just corruption or an synchronization error")); |
834 |
|
|
else |
835 |
|
|
{ |
836 |
|
|
u32 seqno; |
837 |
|
|
tap_packet *d = p->unpack (this, seqno); |
838 |
|
|
|
839 |
|
|
if (seqno <= iseqno - 32) |
840 |
|
|
slog (L_ERR, _("received duplicate or outdated packet (received %08lx, expected %08lx)\n" |
841 |
|
|
"possible replay attack, or just massive packet reordering"), seqno, iseqno + 1);//D |
842 |
|
|
else if (seqno > iseqno + 32) |
843 |
|
|
slog (L_ERR, _("received duplicate or out-of-sync packet (received %08lx, expected %08lx)\n" |
844 |
|
|
"possible replay attack, or just massive packet loss"), seqno, iseqno + 1);//D |
845 |
|
|
else |
846 |
|
|
{ |
847 |
|
|
if (seqno > iseqno) |
848 |
|
|
{ |
849 |
|
|
ismask <<= seqno - iseqno; |
850 |
|
|
iseqno = seqno; |
851 |
|
|
} |
852 |
|
|
|
853 |
|
|
u32 mask = 1 << (iseqno - seqno); |
854 |
|
|
|
855 |
|
|
//printf ("received seqno %08lx, iseqno %08lx, mask %08lx is %08lx\n", seqno, iseqno, mask, ismask); |
856 |
|
|
if (ismask & mask) |
857 |
|
|
slog (L_ERR, _("received duplicate packet (received %08lx, expected %08lx)\n" |
858 |
|
|
"possible replay attack, or just packet duplication"), seqno, iseqno + 1);//D |
859 |
|
|
else |
860 |
|
|
{ |
861 |
|
|
ismask |= mask; |
862 |
|
|
|
863 |
|
|
vpn->tap->send (d); |
864 |
|
|
|
865 |
|
|
if (p->dst () == 0) // re-broadcast |
866 |
|
|
for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i) |
867 |
|
|
{ |
868 |
|
|
connection *c = *i; |
869 |
|
|
|
870 |
|
|
if (c->conf != THISNODE && c->conf != conf) |
871 |
|
|
c->inject_data_packet (d); |
872 |
|
|
} |
873 |
|
|
|
874 |
|
|
delete d; |
875 |
|
|
|
876 |
|
|
break; |
877 |
|
|
} |
878 |
|
|
} |
879 |
|
|
} |
880 |
|
|
} |
881 |
|
|
else |
882 |
|
|
slog (L_ERR, _("received data packet from unknown source %s"), (const char *)sockinfo (ssa));//D |
883 |
|
|
} |
884 |
|
|
|
885 |
|
|
send_reset (ssa); |
886 |
|
|
break; |
887 |
|
|
|
888 |
|
|
case vpn_packet::PT_CONNECT_REQ: |
889 |
|
|
if (ictx && octx && *ssa == sa && pkt->hmac_chk (ictx)) |
890 |
|
|
{ |
891 |
|
|
connect_req_packet *p = (connect_req_packet *) pkt; |
892 |
|
|
|
893 |
|
|
assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything |
894 |
|
|
|
895 |
|
|
connection *c = vpn->conns[p->id - 1]; |
896 |
|
|
|
897 |
|
|
slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n", |
898 |
|
|
conf->id, p->id, c->ictx && c->octx); |
899 |
|
|
|
900 |
|
|
if (c->ictx && c->octx) |
901 |
|
|
{ |
902 |
pcg |
1.4 |
// send connect_info packets to both sides, in case one is |
903 |
|
|
// behind a nat firewall (or both ;) |
904 |
|
|
{ |
905 |
|
|
sockinfo si(sa); |
906 |
|
|
|
907 |
|
|
slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", |
908 |
|
|
c->conf->id, conf->id, (const char *)si); |
909 |
pcg |
1.1 |
|
910 |
pcg |
1.4 |
connect_info_packet *r = new connect_info_packet (c->conf->id, conf->id, si); |
911 |
pcg |
1.1 |
|
912 |
pcg |
1.4 |
r->hmac_set (c->octx); |
913 |
|
|
vpn->send_vpn_packet (r, &c->sa); |
914 |
pcg |
1.1 |
|
915 |
pcg |
1.4 |
delete r; |
916 |
|
|
} |
917 |
|
|
|
918 |
|
|
{ |
919 |
|
|
sockinfo si(c->sa); |
920 |
|
|
|
921 |
|
|
slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", |
922 |
|
|
conf->id, c->conf->id, (const char *)si); |
923 |
|
|
|
924 |
|
|
connect_info_packet *r = new connect_info_packet (conf->id, c->conf->id, si); |
925 |
|
|
|
926 |
|
|
r->hmac_set (octx); |
927 |
|
|
vpn->send_vpn_packet (r, &sa); |
928 |
|
|
|
929 |
|
|
delete r; |
930 |
|
|
} |
931 |
pcg |
1.1 |
} |
932 |
|
|
} |
933 |
|
|
|
934 |
|
|
break; |
935 |
|
|
|
936 |
|
|
case vpn_packet::PT_CONNECT_INFO: |
937 |
|
|
if (ictx && octx && *ssa == sa && pkt->hmac_chk (ictx)) |
938 |
|
|
{ |
939 |
|
|
connect_info_packet *p = (connect_info_packet *) pkt; |
940 |
|
|
|
941 |
|
|
assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything |
942 |
|
|
|
943 |
|
|
connection *c = vpn->conns[p->id - 1]; |
944 |
|
|
|
945 |
|
|
slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)", |
946 |
|
|
conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx); |
947 |
|
|
|
948 |
|
|
c->send_auth (AUTH_INIT, p->si.sa ()); |
949 |
|
|
} |
950 |
|
|
break; |
951 |
|
|
|
952 |
|
|
default: |
953 |
|
|
send_reset (ssa); |
954 |
|
|
break; |
955 |
|
|
} |
956 |
|
|
} |
957 |
|
|
|
958 |
|
|
void connection::timer () |
959 |
|
|
{ |
960 |
|
|
if (conf != THISNODE) |
961 |
|
|
{ |
962 |
pcg |
1.5 |
if (now >= next_retry && connectmode == conf_node::C_ALWAYS) |
963 |
pcg |
1.1 |
establish_connection (); |
964 |
|
|
|
965 |
|
|
if (ictx && octx) |
966 |
|
|
{ |
967 |
|
|
if (now >= next_rekey) |
968 |
|
|
rekey (); |
969 |
|
|
else if (now >= last_activity + ::conf.keepalive + 30) |
970 |
|
|
{ |
971 |
|
|
reset_connection (); |
972 |
|
|
establish_connection (); |
973 |
|
|
} |
974 |
|
|
else if (now >= last_activity + ::conf.keepalive) |
975 |
|
|
if (conf->connectmode != conf_node::C_ONDEMAND |
976 |
|
|
|| THISNODE->connectmode != conf_node::C_ONDEMAND) |
977 |
|
|
send_ping (&sa); |
978 |
|
|
else |
979 |
|
|
reset_connection (); |
980 |
|
|
|
981 |
|
|
} |
982 |
|
|
} |
983 |
|
|
} |
984 |
|
|
|
985 |
|
|
void connection::connect_request (int id) |
986 |
|
|
{ |
987 |
|
|
connect_req_packet *p = new connect_req_packet (conf->id, id); |
988 |
|
|
|
989 |
|
|
slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", id, conf->id); |
990 |
|
|
p->hmac_set (octx); |
991 |
|
|
vpn->send_vpn_packet (p, &sa); |
992 |
|
|
|
993 |
|
|
delete p; |
994 |
|
|
} |
995 |
|
|
|
996 |
|
|
void connection::script_node () |
997 |
|
|
{ |
998 |
|
|
vpn->script_if_up (); |
999 |
|
|
|
1000 |
|
|
char *env; |
1001 |
|
|
asprintf (&env, "DESTID=%d", conf->id); |
1002 |
|
|
putenv (env); |
1003 |
|
|
asprintf (&env, "DESTNODE=%s", conf->nodename); |
1004 |
|
|
putenv (env); |
1005 |
|
|
asprintf (&env, "DESTIP=%s", inet_ntoa (sa.sin_addr)); |
1006 |
|
|
putenv (env); |
1007 |
|
|
asprintf (&env, "DESTPORT=%d", ntohs (sa.sin_port)); |
1008 |
|
|
putenv (env); |
1009 |
|
|
} |
1010 |
|
|
|
1011 |
|
|
const char *connection::script_node_up () |
1012 |
|
|
{ |
1013 |
|
|
script_node (); |
1014 |
|
|
|
1015 |
|
|
putenv ("STATE=up"); |
1016 |
|
|
|
1017 |
|
|
return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; |
1018 |
|
|
} |
1019 |
|
|
|
1020 |
|
|
const char *connection::script_node_down () |
1021 |
|
|
{ |
1022 |
|
|
script_node (); |
1023 |
|
|
|
1024 |
|
|
putenv ("STATE=down"); |
1025 |
|
|
|
1026 |
|
|
return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; |
1027 |
|
|
} |
1028 |
|
|
|
1029 |
|
|
///////////////////////////////////////////////////////////////////////////// |
1030 |
|
|
|
1031 |
|
|
vpn::vpn (void) |
1032 |
|
|
{} |
1033 |
|
|
|
1034 |
|
|
const char *vpn::script_if_up () |
1035 |
|
|
{ |
1036 |
|
|
// the tunnel device mtu should be the physical mtu - overhead |
1037 |
|
|
// the tricky part is rounding to the cipher key blocksize |
1038 |
|
|
int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - UDP_OVERHEAD; |
1039 |
|
|
mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
1040 |
|
|
mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round |
1041 |
|
|
mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
1042 |
|
|
|
1043 |
|
|
char *env; |
1044 |
|
|
asprintf (&env, "CONFBASE=%s", confbase); |
1045 |
|
|
putenv (env); |
1046 |
|
|
asprintf (&env, "NODENAME=%s", THISNODE->nodename); |
1047 |
|
|
putenv (env); |
1048 |
|
|
asprintf (&env, "NODEID=%d", THISNODE->id); |
1049 |
|
|
putenv (env); |
1050 |
|
|
asprintf (&env, "IFNAME=%s", tap->interface ()); |
1051 |
|
|
putenv (env); |
1052 |
|
|
asprintf (&env, "MTU=%d", mtu); |
1053 |
|
|
putenv (env); |
1054 |
|
|
asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x", |
1055 |
|
|
0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8, |
1056 |
|
|
THISNODE->id & 0xff); |
1057 |
|
|
putenv (env); |
1058 |
|
|
|
1059 |
|
|
return ::conf.script_if_up ? ::conf.script_if_up : "if-up"; |
1060 |
|
|
} |
1061 |
|
|
|
1062 |
|
|
int |
1063 |
|
|
vpn::setup (void) |
1064 |
|
|
{ |
1065 |
|
|
struct sockaddr_in sa; |
1066 |
|
|
|
1067 |
|
|
socket_fd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
1068 |
|
|
if (socket_fd < 0) |
1069 |
|
|
return -1; |
1070 |
|
|
|
1071 |
|
|
fill_sa (&sa, THISNODE); |
1072 |
|
|
|
1073 |
|
|
if (bind (socket_fd, (sockaddr *)&sa, sizeof (sa))) |
1074 |
|
|
{ |
1075 |
|
|
slog (L_ERR, _("can't bind to %s: %s"), (const char *)sockinfo(sa), strerror (errno)); |
1076 |
|
|
exit (1); |
1077 |
|
|
} |
1078 |
|
|
|
1079 |
|
|
#ifdef IP_MTU_DISCOVER |
1080 |
|
|
// this I really consider a linux bug. I am neither connected |
1081 |
|
|
// nor do I fragment myself. Linux still sets DF and doesn't |
1082 |
|
|
// fragment for me sometimes. |
1083 |
|
|
{ |
1084 |
|
|
int oval = IP_PMTUDISC_DONT; |
1085 |
|
|
setsockopt (socket_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
1086 |
|
|
} |
1087 |
|
|
#endif |
1088 |
|
|
{ |
1089 |
|
|
int oval = 1; |
1090 |
|
|
setsockopt (socket_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
1091 |
|
|
} |
1092 |
|
|
|
1093 |
|
|
tap = new tap_device (); |
1094 |
|
|
if (!tap) //D this, of course, never catches |
1095 |
|
|
{ |
1096 |
|
|
slog (L_ERR, _("cannot create network interface '%s'"), conf.ifname); |
1097 |
|
|
exit (1); |
1098 |
|
|
} |
1099 |
|
|
|
1100 |
|
|
run_script (this, &vpn::script_if_up, true); |
1101 |
|
|
|
1102 |
|
|
return 0; |
1103 |
|
|
} |
1104 |
|
|
|
1105 |
|
|
void |
1106 |
pcg |
1.6 |
vpn::send_vpn_packet (vpn_packet *pkt, SOCKADDR *sa, int tos) |
1107 |
pcg |
1.1 |
{ |
1108 |
pcg |
1.6 |
setsockopt (socket_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
1109 |
pcg |
1.1 |
sendto (socket_fd, &((*pkt)[0]), pkt->len, 0, (sockaddr *)sa, sizeof (*sa)); |
1110 |
|
|
} |
1111 |
|
|
|
1112 |
|
|
void |
1113 |
|
|
vpn::shutdown_all () |
1114 |
|
|
{ |
1115 |
|
|
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1116 |
|
|
(*c)->shutdown (); |
1117 |
|
|
} |
1118 |
|
|
|
1119 |
|
|
void |
1120 |
|
|
vpn::reconnect_all () |
1121 |
|
|
{ |
1122 |
|
|
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1123 |
|
|
delete *c; |
1124 |
|
|
|
1125 |
|
|
conns.clear (); |
1126 |
|
|
|
1127 |
|
|
for (configuration::node_vector::iterator i = conf.nodes.begin (); |
1128 |
|
|
i != conf.nodes.end (); ++i) |
1129 |
|
|
{ |
1130 |
|
|
connection *conn = new connection (this); |
1131 |
|
|
|
1132 |
|
|
conn->conf = *i; |
1133 |
|
|
conns.push_back (conn); |
1134 |
|
|
|
1135 |
pcg |
1.5 |
conn->establish_connection (); |
1136 |
pcg |
1.1 |
} |
1137 |
|
|
} |
1138 |
|
|
|
1139 |
|
|
connection *vpn::find_router () |
1140 |
|
|
{ |
1141 |
|
|
u32 prio = 0; |
1142 |
|
|
connection *router = 0; |
1143 |
|
|
|
1144 |
|
|
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
1145 |
|
|
{ |
1146 |
|
|
connection *c = *i; |
1147 |
|
|
|
1148 |
|
|
if (c->conf->routerprio > prio |
1149 |
pcg |
1.5 |
&& c->connectmode == conf_node::C_ALWAYS |
1150 |
pcg |
1.1 |
&& c->conf != THISNODE |
1151 |
|
|
&& c->ictx && c->octx) |
1152 |
|
|
{ |
1153 |
|
|
prio = c->conf->routerprio; |
1154 |
|
|
router = c; |
1155 |
|
|
} |
1156 |
|
|
} |
1157 |
|
|
|
1158 |
|
|
return router; |
1159 |
|
|
} |
1160 |
|
|
|
1161 |
|
|
void vpn::connect_request (int id) |
1162 |
|
|
{ |
1163 |
|
|
connection *c = find_router (); |
1164 |
|
|
|
1165 |
|
|
if (c) |
1166 |
|
|
c->connect_request (id); |
1167 |
pcg |
1.3 |
//else // does not work, because all others must connect to the same router |
1168 |
|
|
// // no router found, aggressively connect to all routers |
1169 |
|
|
// for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
1170 |
|
|
// if ((*i)->conf->routerprio) |
1171 |
|
|
// (*i)->establish_connection (); |
1172 |
pcg |
1.1 |
} |
1173 |
|
|
|
1174 |
|
|
void |
1175 |
|
|
vpn::main_loop () |
1176 |
|
|
{ |
1177 |
|
|
struct pollfd pollfd[2]; |
1178 |
|
|
|
1179 |
|
|
pollfd[0].fd = tap->fd; |
1180 |
|
|
pollfd[0].events = POLLIN; |
1181 |
|
|
pollfd[1].fd = socket_fd; |
1182 |
|
|
pollfd[1].events = POLLIN; |
1183 |
|
|
|
1184 |
|
|
events = 0; |
1185 |
|
|
now = time (0); |
1186 |
|
|
next_timecheck = now + 1; |
1187 |
|
|
|
1188 |
|
|
reconnect_all (); |
1189 |
|
|
|
1190 |
|
|
for (;;) |
1191 |
|
|
{ |
1192 |
|
|
int npoll = poll (pollfd, 2, (next_timecheck - now) * 1000); |
1193 |
|
|
|
1194 |
|
|
now = time (0); |
1195 |
|
|
|
1196 |
|
|
if (npoll > 0) |
1197 |
|
|
{ |
1198 |
|
|
if (pollfd[1].revents) |
1199 |
|
|
{ |
1200 |
|
|
if (pollfd[1].revents & (POLLIN | POLLERR)) |
1201 |
|
|
{ |
1202 |
|
|
vpn_packet *pkt = new vpn_packet; |
1203 |
|
|
struct sockaddr_in sa; |
1204 |
|
|
socklen_t sa_len = sizeof (sa); |
1205 |
|
|
int len; |
1206 |
|
|
|
1207 |
|
|
len = recvfrom (socket_fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
1208 |
|
|
|
1209 |
|
|
if (len > 0) |
1210 |
|
|
{ |
1211 |
|
|
pkt->len = len; |
1212 |
|
|
|
1213 |
|
|
unsigned int src = pkt->src (); |
1214 |
|
|
unsigned int dst = pkt->dst (); |
1215 |
|
|
|
1216 |
|
|
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d"), |
1217 |
|
|
(const char *)sockinfo (sa), pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
1218 |
|
|
|
1219 |
|
|
if (dst > conns.size () || pkt->typ () >= vpn_packet::PT_MAX) |
1220 |
|
|
slog (L_WARN, _("<<? received CORRUPTED packet type %d from %d to %d"), |
1221 |
|
|
pkt->typ (), pkt->src (), pkt->dst ()); |
1222 |
|
|
else if (dst == 0 && !THISNODE->routerprio) |
1223 |
|
|
slog (L_WARN, _("<<%d received broadcast, but we are no router"), dst); |
1224 |
|
|
else if (dst != 0 && dst != THISNODE->id) |
1225 |
|
|
slog (L_WARN, |
1226 |
|
|
_("received frame for node %d ('%s') from %s, but this is node %d ('%s')"), |
1227 |
|
|
dst, conns[dst - 1]->conf->nodename, |
1228 |
|
|
(const char *)sockinfo (sa), |
1229 |
|
|
THISNODE->id, THISNODE->nodename); |
1230 |
|
|
else if (src == 0 || src > conns.size ()) |
1231 |
|
|
slog (L_WARN, _("received frame from unknown node %d (%s)"), src, (const char *)sockinfo (sa)); |
1232 |
|
|
else |
1233 |
|
|
conns[src - 1]->recv_vpn_packet (pkt, &sa); |
1234 |
|
|
} |
1235 |
|
|
else |
1236 |
|
|
{ |
1237 |
|
|
// probably ECONNRESET or somesuch |
1238 |
|
|
slog (L_DEBUG, _("%s: %s"), (const char *)sockinfo(sa), strerror (errno)); |
1239 |
|
|
} |
1240 |
|
|
|
1241 |
|
|
delete pkt; |
1242 |
|
|
} |
1243 |
|
|
else if (pollfd[1].revents & POLLHUP) |
1244 |
|
|
{ |
1245 |
|
|
// this cannot ;) happen on udp sockets |
1246 |
|
|
slog (L_ERR, _("FATAL: POLLHUP on socket fd, terminating.")); |
1247 |
|
|
exit (1); |
1248 |
|
|
} |
1249 |
|
|
else |
1250 |
|
|
{ |
1251 |
|
|
slog (L_ERR, |
1252 |
|
|
_("FATAL: unknown revents %08x in socket, terminating\n"), |
1253 |
|
|
pollfd[1].revents); |
1254 |
|
|
exit (1); |
1255 |
|
|
} |
1256 |
|
|
} |
1257 |
|
|
|
1258 |
|
|
// I use else here to give vpn_packets absolute priority |
1259 |
|
|
else if (pollfd[0].revents) |
1260 |
|
|
{ |
1261 |
|
|
if (pollfd[0].revents & POLLIN) |
1262 |
|
|
{ |
1263 |
|
|
/* process data */ |
1264 |
|
|
tap_packet *pkt; |
1265 |
|
|
|
1266 |
|
|
pkt = tap->recv (); |
1267 |
|
|
|
1268 |
|
|
int dst = mac2id (pkt->dst); |
1269 |
|
|
int src = mac2id (pkt->src); |
1270 |
|
|
|
1271 |
|
|
if (src != THISNODE->id) |
1272 |
|
|
{ |
1273 |
|
|
slog (L_ERR, _("FATAL: tap packet not originating on current node received, terminating.")); |
1274 |
|
|
exit (1); |
1275 |
|
|
} |
1276 |
|
|
|
1277 |
|
|
if (dst == THISNODE->id) |
1278 |
|
|
{ |
1279 |
|
|
slog (L_ERR, _("FATAL: tap packet destined for current node received, terminating.")); |
1280 |
|
|
exit (1); |
1281 |
|
|
} |
1282 |
|
|
|
1283 |
|
|
if (dst > conns.size ()) |
1284 |
|
|
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
1285 |
|
|
else |
1286 |
|
|
{ |
1287 |
|
|
if (dst) |
1288 |
|
|
{ |
1289 |
|
|
// unicast |
1290 |
|
|
if (dst != THISNODE->id) |
1291 |
|
|
conns[dst - 1]->inject_data_packet (pkt); |
1292 |
|
|
} |
1293 |
|
|
else |
1294 |
|
|
{ |
1295 |
|
|
// broadcast, first check router, then self, then english |
1296 |
|
|
connection *router = find_router (); |
1297 |
|
|
|
1298 |
|
|
if (router) |
1299 |
|
|
router->inject_data_packet (pkt, true); |
1300 |
|
|
else |
1301 |
|
|
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
1302 |
|
|
if ((*c)->conf != THISNODE) |
1303 |
|
|
(*c)->inject_data_packet (pkt); |
1304 |
|
|
} |
1305 |
|
|
} |
1306 |
|
|
|
1307 |
|
|
delete pkt; |
1308 |
|
|
} |
1309 |
|
|
else if (pollfd[0].revents & (POLLHUP | POLLERR)) |
1310 |
|
|
{ |
1311 |
|
|
slog (L_ERR, _("FATAL: POLLHUP or POLLERR on network device fd, terminating.")); |
1312 |
|
|
exit (1); |
1313 |
|
|
} |
1314 |
|
|
else |
1315 |
|
|
abort (); |
1316 |
|
|
} |
1317 |
|
|
} |
1318 |
|
|
|
1319 |
|
|
if (events) |
1320 |
|
|
{ |
1321 |
|
|
if (events & EVENT_SHUTDOWN) |
1322 |
|
|
{ |
1323 |
|
|
shutdown_all (); |
1324 |
|
|
|
1325 |
|
|
remove_pid (pidfilename); |
1326 |
|
|
|
1327 |
|
|
slog (L_INFO, _("vped terminating")); |
1328 |
|
|
|
1329 |
|
|
exit (0); |
1330 |
|
|
} |
1331 |
|
|
|
1332 |
|
|
if (events & EVENT_RECONNECT) |
1333 |
|
|
reconnect_all (); |
1334 |
|
|
|
1335 |
|
|
events = 0; |
1336 |
|
|
} |
1337 |
|
|
|
1338 |
|
|
// very very very dumb and crude and inefficient timer handling, or maybe not? |
1339 |
|
|
if (now >= next_timecheck) |
1340 |
|
|
{ |
1341 |
|
|
next_timecheck = now + TIMER_GRANULARITY; |
1342 |
|
|
|
1343 |
|
|
for (conns_vector::iterator c = conns.begin (); |
1344 |
|
|
c != conns.end (); ++c) |
1345 |
|
|
(*c)->timer (); |
1346 |
|
|
} |
1347 |
|
|
} |
1348 |
|
|
} |
1349 |
|
|
|
1350 |
|
|
vpn::~vpn () |
1351 |
|
|
{} |
1352 |
|
|
|