--- gvpe/src/connection.C 2003/04/02 03:25:17 1.2 +++ gvpe/src/connection.C 2008/08/15 18:35:24 1.82 @@ -1,48 +1,106 @@ /* connection.C -- manage a single connection + Copyright (C) 2003-2008 Marc Lehmann - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + This file is part of GVPE. + + GVPE is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by the + Free Software Foundation; either version 3 of the License, or (at your + option) any later version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General + Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, see . + + Additional permission under GNU GPL version 3 section 7 + + If you modify this Program, or any covered work, by linking or + combining it with the OpenSSL project's OpenSSL library (or a modified + version of that library), containing parts covered by the terms of the + OpenSSL or SSLeay licenses, the licensors of this Program grant you + additional permission to convey the resulting work. Corresponding + Source for a non-source form of such a combination shall include the + source code for the parts of OpenSSL used as well as that of the + covered work. */ #include "config.h" -extern "C" { -# include "lzf/lzf.h" -} - #include +#include +#include #include #include #include #include -#include "gettext.h" - #include "conf.h" #include "slog.h" #include "device.h" #include "vpn.h" #include "connection.h" +#include "netcompat.h" + #if !HAVE_RAND_PSEUDO_BYTES # define RAND_pseudo_bytes RAND_bytes #endif #define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic +#define ULTRA_FAST 1 +#define HLOG 15 +#include "lzf/lzf.h" +#include "lzf/lzf_c.c" +#include "lzf/lzf_d.c" + +////////////////////////////////////////////////////////////////////////////// + +static std::queue< std::pair > rs_queue; +static ev::child rs_child_ev; + +void // c++ requires external linkage here, apparently :( +rs_child_cb (ev::child &w, int revents) +{ + w.stop (); + + if (rs_queue.empty ()) + return; + + pid_t pid = run_script (*rs_queue.front ().first, false); + if (pid) + { + w.set (pid); + w.start (); + } + else + slog (L_WARN, rs_queue.front ().second); + + delete rs_queue.front ().first; + rs_queue.pop (); +} + +// despite the fancy name, this is quite a hack +static void +run_script_queued (run_script_cb *cb, const char *warnmsg) +{ + rs_queue.push (std::make_pair (cb, warnmsg)); + + if (!rs_child_ev.is_active ()) + { + rs_child_ev.set (); + rs_child_ev (); + } +} + +////////////////////////////////////////////////////////////////////////////// + struct crypto_ctx { EVP_CIPHER_CTX cctx; @@ -55,14 +113,14 @@ crypto_ctx::crypto_ctx (const rsachallenge &challenge, int enc) { EVP_CIPHER_CTX_init (&cctx); - EVP_CipherInit_ex (&cctx, CIPHER, 0, &challenge[CHG_CIPHER_KEY], 0, enc); + require (EVP_CipherInit_ex (&cctx, CIPHER, 0, &challenge[CHG_CIPHER_KEY], 0, enc)); HMAC_CTX_init (&hctx); HMAC_Init_ex (&hctx, &challenge[CHG_HMAC_KEY], HMAC_KEYLEN, DIGEST, 0); } crypto_ctx::~crypto_ctx () { - EVP_CIPHER_CTX_cleanup (&cctx); + require (EVP_CIPHER_CTX_cleanup (&cctx)); HMAC_CTX_cleanup (&hctx); } @@ -72,14 +130,15 @@ EVP_MD_CTX ctx; EVP_MD_CTX_init (&ctx); - EVP_DigestInit (&ctx, RSA_HASH); - EVP_DigestUpdate(&ctx, &chg, sizeof chg); - EVP_DigestUpdate(&ctx, &id, sizeof id); - EVP_DigestFinal (&ctx, (unsigned char *)&h, 0); + require (EVP_DigestInit (&ctx, RSA_HASH)); + require (EVP_DigestUpdate(&ctx, &chg, sizeof chg)); + require (EVP_DigestUpdate(&ctx, &id, sizeof id)); + require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0)); EVP_MD_CTX_cleanup (&ctx); } -struct rsa_entry { +struct rsa_entry +{ tstamp expire; rsaid id; rsachallenge chg; @@ -87,60 +146,60 @@ struct rsa_cache : list { - void cleaner_cb (tstamp &ts); time_watcher cleaner; + inline void cleaner_cb (ev::timer &w, int revents); ev::timer cleaner; bool find (const rsaid &id, rsachallenge &chg) - { - for (iterator i = begin (); i != end (); ++i) - { - if (!memcmp (&id, &i->id, sizeof id) && i->expire > NOW) - { - memcpy (&chg, &i->chg, sizeof chg); + { + for (iterator i = begin (); i != end (); ++i) + { + if (!memcmp (&id, &i->id, sizeof id) && i->expire > ev_now ()) + { + memcpy (&chg, &i->chg, sizeof chg); - erase (i); - return true; - } - } + erase (i); + return true; + } + } - if (cleaner.at < NOW) - cleaner.start (NOW + RSA_TTL); + if (!cleaner.is_active ()) + cleaner.again (); - return false; - } + return false; + } void gen (rsaid &id, rsachallenge &chg) - { - rsa_entry e; + { + rsa_entry e; - RAND_bytes ((unsigned char *)&id, sizeof id); - RAND_bytes ((unsigned char *)&chg, sizeof chg); + RAND_bytes ((unsigned char *)&id, sizeof id); + RAND_bytes ((unsigned char *)&chg, sizeof chg); - e.expire = NOW + RSA_TTL; - e.id = id; - memcpy (&e.chg, &chg, sizeof chg); + e.expire = ev_now () + RSA_TTL; + e.id = id; + memcpy (&e.chg, &chg, sizeof chg); - push_back (e); + push_back (e); - if (cleaner.at < NOW) - cleaner.start (NOW + RSA_TTL); - } + if (!cleaner.is_active ()) + cleaner.again (); + } rsa_cache () - : cleaner (this, &rsa_cache::cleaner_cb) - { } + { + cleaner.set (this); + cleaner.set (RSA_TTL, RSA_TTL); + } } rsa_cache; -void rsa_cache::cleaner_cb (tstamp &ts) +void rsa_cache::cleaner_cb (ev::timer &w, int revents) { if (empty ()) - ts = TSTAMP_CANCEL; + w.stop (); else { - ts = NOW + RSA_TTL; - for (iterator i = begin (); i != end (); ) - if (i->expire <= NOW) + if (i->expire <= ev_now ()) i = erase (i); else ++i; @@ -149,46 +208,80 @@ ////////////////////////////////////////////////////////////////////////////// -void pkt_queue::put (tap_packet *p) +pkt_queue::pkt_queue (double max_ttl, int max_queue) +: max_ttl (max_ttl), max_queue (max_queue) { - if (queue[i]) - { - delete queue[i]; - j = (j + 1) % QUEUEDEPTH; - } + queue = new pkt [max_queue]; - queue[i] = p; + i = 0; + j = 0; - i = (i + 1) % QUEUEDEPTH; + expire.set (this); } -tap_packet *pkt_queue::get () +pkt_queue::~pkt_queue () +{ + while (net_packet *p = get ()) + delete p; + + delete [] queue; +} + +void pkt_queue::expire_cb (ev::timer &w, int revents) { - tap_packet *p = queue[j]; + ev_tstamp expire = ev_now () - max_ttl; - if (p) + for (;;) { - queue[j] = 0; - j = (j + 1) % QUEUEDEPTH; - } + if (empty ()) + break; - return p; + double diff = queue[j].tstamp - expire; + + if (diff >= 0.) + { + w.start (diff > 0.5 ? diff : 0.5); + break; + } + + delete get (); + } } -pkt_queue::pkt_queue () +void pkt_queue::put (net_packet *p) { - memset (queue, 0, sizeof (queue)); - i = 0; - j = 0; + ev_tstamp now = ev_now (); + + // start expiry timer + if (empty ()) + expire.start (max_ttl); + + int ni = i + 1 == max_queue ? 0 : i + 1; + + if (ni == j) + delete get (); + + queue[i].pkt = p; + queue[i].tstamp = now; + + i = ni; } -pkt_queue::~pkt_queue () +net_packet *pkt_queue::get () { - for (i = QUEUEDEPTH; --i > 0; ) - delete queue[i]; + if (empty ()) + return 0; + + net_packet *p = queue[j].pkt; + queue[j].pkt = 0; + + j = j + 1 == max_queue ? 0 : j + 1; + + return p; } -struct net_rateinfo { +struct net_rateinfo +{ u32 host; double pcnt, diff; tstamp last; @@ -199,11 +292,12 @@ // but low on resources. struct net_rate_limiter : list { - static const double ALPHA = 1. - 1. / 90.; // allow bursts - static const double CUTOFF = 20.; // one event every CUTOFF seconds - static const double EXPIRE = CUTOFF * 30.; // expire entries after this time +# define NRL_ALPHA (1. - 1. / 600.) // allow bursts +# define NRL_CUTOFF 10. // one event every CUTOFF seconds +# define NRL_EXPIRE (NRL_CUTOFF * 30.) // expire entries after this time +# define NRL_MAXDIF (NRL_CUTOFF * (1. / (1. - NRL_ALPHA))) // maximum diff /count value - bool can (const sockinfo &si) { return can((u32)si.host); } + bool can (const sockinfo &si) { return can((u32)si.host); } bool can (u32 host); }; @@ -216,7 +310,7 @@ for (i = begin (); i != end (); ) if (i->host == host) break; - else if (i->last < NOW - EXPIRE) + else if (i->last < ev_now () - NRL_EXPIRE) i = erase (i); else i++; @@ -227,8 +321,8 @@ ri.host = host; ri.pcnt = 1.; - ri.diff = CUTOFF * (1. / (1. - ALPHA)); - ri.last = NOW; + ri.diff = NRL_MAXDIF; + ri.last = ev_now (); push_front (ri); @@ -239,14 +333,21 @@ net_rateinfo ri (*i); erase (i); - ri.pcnt = ri.pcnt * ALPHA; - ri.diff = ri.diff * ALPHA + (NOW - ri.last); + ri.pcnt = ri.pcnt * NRL_ALPHA; + ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last); + + ri.last = ev_now (); - ri.last = NOW; + double dif = ri.diff / ri.pcnt; - bool send = ri.diff / ri.pcnt > CUTOFF; + bool send = dif > NRL_CUTOFF; - if (send) + if (dif > NRL_MAXDIF) + { + ri.pcnt = 1.; + ri.diff = NRL_MAXDIF; + } + else if (send) ri.pcnt++; push_front (ri); @@ -287,9 +388,9 @@ return !memcmp (hmac, hmac_digest, HMACLENGTH); } -void vpn_packet::set_hdr (ptype type, unsigned int dst) +void vpn_packet::set_hdr (ptype type_, unsigned int dst) { - this->type = type; + type = type_; int src = THISNODE->id; @@ -301,7 +402,7 @@ #define MAXVPNDATA (MAX_MTU - 6 - 6) #define DATAHDR (sizeof (u32) + RAND_SIZE) -struct vpndata_packet:vpn_packet +struct vpndata_packet : vpn_packet { u8 data[MAXVPNDATA + DATAHDR]; // seqno @@ -324,21 +425,24 @@ #if ENABLE_COMPRESSION u8 cdata[MAX_MTU]; - u32 cl; - cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); - if (cl) + if (conn->features & ENABLE_COMPRESSION) { - type = PT_DATA_COMPRESSED; - d = cdata; - l = cl + 2; + u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); - d[0] = cl >> 8; - d[1] = cl; + if (cl) + { + type = PT_DATA_COMPRESSED; + d = cdata; + l = cl + 2; + + d[0] = cl >> 8; + d[1] = cl; + } } #endif - EVP_EncryptInit_ex (cctx, 0, 0, 0, 0); + require (EVP_EncryptInit_ex (cctx, 0, 0, 0, 0)); struct { #if RAND_SIZE @@ -352,17 +456,17 @@ RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE); #endif - EVP_EncryptUpdate (cctx, + require (EVP_EncryptUpdate (cctx, (unsigned char *) data + outl, &outl2, - (unsigned char *) &datahdr, DATAHDR); + (unsigned char *) &datahdr, DATAHDR)); outl += outl2; - EVP_EncryptUpdate (cctx, + require (EVP_EncryptUpdate (cctx, (unsigned char *) data + outl, &outl2, - (unsigned char *) d, l); + (unsigned char *) d, l)); outl += outl2; - EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2); + require (EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2)); outl += outl2; len = outl + data_hdr_size (); @@ -381,7 +485,7 @@ u8 *d; u32 l = len - data_hdr_size (); - EVP_DecryptInit_ex (cctx, 0, 0, 0, 0); + require (EVP_DecryptInit_ex (cctx, 0, 0, 0, 0)); #if ENABLE_COMPRESSION u8 cdata[MAX_MTU]; @@ -393,12 +497,12 @@ d = &(*p)[6 + 6 - DATAHDR]; /* this overwrites part of the src mac, but we fix that later */ - EVP_DecryptUpdate (cctx, + require (EVP_DecryptUpdate (cctx, d, &outl2, - (unsigned char *)&data, len - data_hdr_size ()); + (unsigned char *)&data, len - data_hdr_size ())); outl += outl2; - EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2); + require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2)); outl += outl2; seqno = ntohl (*(u32 *)(d + RAND_SIZE)); @@ -437,17 +541,26 @@ // field comes before this data, so peers with other // hmacs simply will not work. u8 prot_major, prot_minor, randsize, hmaclen; - u8 flags, challengelen, pad2, pad3; + u8 flags, challengelen, features, pad3; u32 cipher_nid, digest_nid, hmac_nid; - const u8 curflags () const - { - return 0x80 - | (ENABLE_COMPRESSION ? 0x01 : 0x00); - } - void setup (ptype type, int dst); bool chk_config () const; + + static u8 get_features () + { + u8 f = 0; +#if ENABLE_COMPRESSION + f |= FEATURE_COMPRESSION; +#endif +#if ENABLE_ROHC + f |= FEATURE_ROHC; +#endif +#if ENABLE_BRIDGING + f |= FEATURE_BRIDGING; +#endif + return f; + } }; void config_packet::setup (ptype type, int dst) @@ -456,8 +569,9 @@ prot_minor = PROTOCOL_MINOR; randsize = RAND_SIZE; hmaclen = HMACLENGTH; - flags = curflags (); + flags = 0; challengelen = sizeof (rsachallenge); + features = get_features (); cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); digest_nid = htonl (EVP_MD_type (RSA_HASH)); @@ -469,21 +583,31 @@ bool config_packet::chk_config () const { - return prot_major == PROTOCOL_MAJOR - && randsize == RAND_SIZE - && hmaclen == HMACLENGTH - && flags == curflags () - && challengelen == sizeof (rsachallenge) - && cipher_nid == htonl (EVP_CIPHER_nid (CIPHER)) - && digest_nid == htonl (EVP_MD_type (RSA_HASH)) - && hmac_nid == htonl (EVP_MD_type (DIGEST)); + if (prot_major != PROTOCOL_MAJOR) + slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); + else if (randsize != RAND_SIZE) + slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE); + else if (hmaclen != HMACLENGTH) + slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH); + else if (challengelen != sizeof (rsachallenge)) + slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge)); + else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER))) + slog (L_WARN, _("cipher mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER)); + else if (digest_nid != htonl (EVP_MD_type (RSA_HASH))) + slog (L_WARN, _("digest mismatch (remote %x <=> local %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH)); + else if (hmac_nid != htonl (EVP_MD_type (DIGEST))) + slog (L_WARN, _("hmac mismatch (remote %x <=> local %x)"), ntohl (hmac_nid), EVP_MD_type (DIGEST)); + else + return true; + + return false; } struct auth_req_packet : config_packet { char magic[8]; u8 initiate; // false if this is just an automatic reply - u8 protocols; // supported protocols (will get patches on forward) + u8 protocols; // supported protocols (will be patched on forward) u8 pad2, pad3; rsaid id; rsaencrdata encr; @@ -548,9 +672,87 @@ ///////////////////////////////////////////////////////////////////////////// void -connection::reset_dstaddr () +connection::connection_established () +{ + slog (L_NOISE, _("%s: possible connection establish (ictx %d, octx %d)"), conf->nodename, !!ictx, !!octx); + + if (ictx && octx) + { + // make sure rekeying timeouts are slightly asymmetric + ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); + rekey.start (rekey_interval, rekey_interval); + keepalive.start (::conf.keepalive); + + // send queued packets + if (ictx && octx) + { + while (tap_packet *p = (tap_packet *)data_queue.get ()) + { + if (p->len) send_data_packet (p); + delete p; + } + + while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) + { + if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); + delete p; + } + } + + vpn->connection_established (this); + } + else + { + retry_cnt = 0; + establish_connection.start (5); + keepalive.stop (); + rekey.stop (); + } +} + +void +connection::reset_si () +{ + if (vpn->can_direct (THISNODE, conf)) + protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ()); + else + { + slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename); + protocol = 0; + } + + si.set (conf, protocol); + + is_direct = si.valid (); +} + +// ensure sockinfo is valid, forward if necessary +const sockinfo & +connection::forward_si (const sockinfo &si) const +{ + if (!si.valid ()) + { + connection *r = vpn->find_router_for (this); + + if (r) + { + slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."), + conf->nodename, r->conf->nodename); + return r->si; + } + else + slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."), + conf->nodename); + } + + return si; +} + +void +connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) { - si.set (conf); + if (!vpn->send_vpn_packet (pkt, si, tos)) + reset_connection (); } void @@ -559,6 +761,9 @@ ping_packet *pkt = new ping_packet; pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); + + slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); + send_vpn_packet (pkt, si, IPTOS_LOWDELAY); delete pkt; @@ -583,31 +788,15 @@ { auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); - protocol = best_protocol (THISNODE->protocols & conf->protocols); - - // mask out protocols we cannot establish - if (!conf->udp_port) protocol &= ~PROT_UDPv4; - if (!conf->tcp_port) protocol &= ~PROT_TCPv4; - - if (protocol) - { - rsachallenge chg; - - rsa_cache.gen (pkt->id, chg); - - if (0 > RSA_public_encrypt (sizeof chg, - (unsigned char *)&chg, (unsigned char *)&pkt->encr, - conf->rsa_key, RSA_PKCS1_OAEP_PADDING)) - fatal ("RSA_public_encrypt error"); + rsachallenge chg; + rsa_cache.gen (pkt->id, chg); + rsa_encrypt (conf->rsa_key, chg, pkt->encr); - slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)si); + slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); - send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly + send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly - delete pkt; - } - else - ; // silently fail + delete pkt; } void @@ -621,7 +810,7 @@ pkt->hmac_set (octx); - slog (L_TRACE, ">>%d PT_AUTH_RES [%s]", conf->id, (const char *)si); + slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly @@ -631,8 +820,8 @@ void connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) { - slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", - conf->id, rid, (const char *)rsi); + slog (L_TRACE, "%s << PT_CONNECT_INFO(%s,%s)", conf->nodename, + vpn->conns[rid - 1]->conf->nodename, (const char *)rsi); connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); @@ -642,35 +831,66 @@ delete r; } -void -connection::establish_connection_cb (tstamp &ts) +inline void +connection::establish_connection_cb (ev::timer &w, int revents) { - if (ictx || conf == THISNODE - || connectmode == conf_node::C_NEVER - || connectmode == conf_node::C_DISABLED) - ts = TSTAMP_CANCEL; - else if (ts <= NOW) + if (!ictx + && conf != THISNODE + && connectmode != conf_node::C_NEVER + && connectmode != conf_node::C_DISABLED + && !w.is_active ()) { - double retry_int = double (retry_cnt & 3 ? (retry_cnt & 3) : 1 << (retry_cnt >> 2)) * 0.6; + // a bit hacky, if ondemand, and packets are no longer queued, then reset the connection + // and stop trying. should probably be handled by a per-connection expire handler. + if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ()) + { + reset_connection (); + return; + } - if (retry_int < 3600 * 8) - retry_cnt++; + last_establish_attempt = ev_now (); + + ev::tstamp retry_int = ev::tstamp (retry_cnt & 3 + ? (retry_cnt & 3) + 1 + : 1 << (retry_cnt >> 2)); + + reset_si (); - ts = NOW + retry_int; + bool slow = si.prot & PROT_SLOW; - if (conf->hostname) + if (si.prot && !si.host && vpn->can_direct (THISNODE, conf)) { - reset_dstaddr (); - if (si.host && auth_rate_limiter.can (si)) - { - if (retry_cnt < 4) - send_auth_request (si, true); - else - send_ping (si, 0); - } + /*TODO*/ /* start the timer so we don't recurse endlessly */ + w.start (1); + vpn->send_connect_request (this); + } + else + { + if (si.valid ()) + slog (L_DEBUG, _("%s: sending direct connection request to %s."), + conf->nodename, (const char *)si); + + const sockinfo &dsi = forward_si (si); + + slow = slow || (dsi.prot & PROT_SLOW); + + if (dsi.valid () && auth_rate_limiter.can (dsi)) + { + if (retry_cnt < 4) + send_auth_request (dsi, true); + else + send_ping (dsi, 0); + } } + + retry_int *= slow ? 8. : 0.9; + + if (retry_int < conf->max_retry) + retry_cnt++; else - vpn->connect_request (conf->id); + retry_int = conf->max_retry; + + w.start (retry_int); } } @@ -683,20 +903,28 @@ conf->nodename, (const char *)si); if (::conf.script_node_down) - run_script (run_script_cb (this, &connection::script_node_down), false); + { + run_script_cb *cb = new run_script_cb; + cb->set (this); + run_script_queued (cb, _("node-down command execution failed, continuing.")); + } } delete ictx; ictx = 0; delete octx; octx = 0; +#if ENABLE_DNS + dnsv4_reset_connection (); +#endif - si.host= 0; + si.host = 0; - last_activity = 0; + last_activity = 0.; + //last_si_change = 0.; retry_cnt = 0; - rekey.reset (); - keepalive.reset (); - establish_connection.reset (); + rekey.stop (); + keepalive.stop (); + establish_connection.stop (); } void @@ -708,27 +936,25 @@ reset_connection (); } -void -connection::rekey_cb (tstamp &ts) +// poor-man's rekeying +inline void +connection::rekey_cb (ev::timer &w, int revents) { - ts = TSTAMP_CANCEL; - reset_connection (); establish_connection (); } void -connection::send_data_packet (tap_packet *pkt, bool broadcast) +connection::send_data_packet (tap_packet *pkt) { vpndata_packet *p = new vpndata_packet; int tos = 0; - if (conf->inherit_tos - && (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP - && ((*pkt)[14] & 0xf0) == 0x40) // IPv4 + // I am not hilarious about peeking into packets, but so be it. + if (conf->inherit_tos && pkt->is_ipv4 ()) tos = (*pkt)[15] & IPTOS_TOS_MASK; - p->setup (this, broadcast ? 0 : conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs + p->setup (this, conf->id, &((*pkt)[6 + 6]), pkt->len - 6 - 6, ++oseqno); // skip 2 macs send_vpn_packet (p, si, tos); delete p; @@ -738,320 +964,397 @@ } void -connection::inject_data_packet (tap_packet *pkt, bool broadcast) +connection::post_inject_queue () +{ + // force a connection every now and when when packets are sent (max 1/s) + if (ev_now () - last_establish_attempt >= 0.95) // arbitrary + establish_connection.stop (); + + establish_connection (); +} + +void +connection::inject_data_packet (tap_packet *pkt) { if (ictx && octx) - send_data_packet (pkt, broadcast); + send_data_packet (pkt); else { - if (!broadcast)//DDDD - queue.put (new tap_packet (*pkt)); + data_queue.put (new tap_packet (*pkt)); + post_inject_queue (); + } +} - establish_connection (); +void connection::inject_vpn_packet (vpn_packet *pkt, int tos) +{ + if (ictx && octx) + send_vpn_packet (pkt, si, tos); + else + { + vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); + post_inject_queue (); } } void connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) { - last_activity = NOW; + last_activity = ev_now (); + + slog (L_NOISE, "%s >> received packet type %d from %d to %d.", + conf->nodename, pkt->typ (), pkt->src (), pkt->dst ()); - slog (L_NOISE, "<<%d received packet type %d from %d to %d", - conf->id, pkt->typ (), pkt->src (), pkt->dst ()); + if (connectmode == conf_node::C_DISABLED) + return; switch (pkt->typ ()) { - case vpn_packet::PT_PING: - // we send pings instead of auth packets after some retries, - // so reset the retry counter and establish a connection - // when we receive a ping. - if (!ictx) + case vpn_packet::PT_PING: + slog (L_TRACE, "%s >> PT_PING", conf->nodename); + + // we send pings instead of auth packets after some retries, + // so reset the retry counter and establish a connection + // when we receive a ping. + if (!ictx) + { + if (auth_rate_limiter.can (rsi)) + send_auth_request (rsi, true); + } + else + // we would love to change thre socket address here, but ping's aren't + // authenticated, so we best ignore it. + send_ping (rsi, 1); // pong + + break; + + case vpn_packet::PT_PONG: + slog (L_TRACE, "%s >> PT_PONG", conf->nodename); + break; + + case vpn_packet::PT_RESET: { - if (auth_rate_limiter.can (rsi)) - send_auth_request (rsi, true); + reset_connection (); + + config_packet *p = (config_packet *) pkt; + + if (!p->chk_config ()) + { + slog (L_WARN, _("%s(%s): protocol mismatch, disabling node."), + conf->nodename, (const char *)rsi); + connectmode = conf_node::C_DISABLED; + } + else if (connectmode == conf_node::C_ALWAYS) + establish_connection (); } - else - send_ping (rsi, 1); // pong + break; - break; + case vpn_packet::PT_AUTH_REQ: + if (auth_rate_limiter.can (rsi)) + { + auth_req_packet *p = (auth_req_packet *) pkt; - case vpn_packet::PT_PONG: - break; + slog (L_TRACE, "%s >> PT_AUTH_REQ(%s)", conf->nodename, p->initiate ? "initiate" : "reply"); - case vpn_packet::PT_RESET: - { - reset_connection (); + if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) + { + if (p->prot_minor != PROTOCOL_MINOR) + slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), + conf->nodename, (const char *)rsi, + PROTOCOL_MINOR, conf->nodename, p->prot_minor); - config_packet *p = (config_packet *) pkt; + if (p->initiate) + send_auth_request (rsi, false); - if (!p->chk_config ()) - { - slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"), - conf->nodename, (const char *)rsi); - connectmode = conf_node::C_DISABLED; + rsachallenge k; + + if (!rsa_decrypt (::conf.rsa_key, p->encr, k)) + { + slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), + conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); + break; + } + else + { + delete octx; + + octx = new crypto_ctx (k, 1); + oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; + + conf->protocols = p->protocols; + features = p->features & config_packet::get_features (); + + send_auth_response (rsi, p->id, k); + + connection_established (); + + break; + } + } + else + slog (L_WARN, _("%s(%s): protocol mismatch."), + conf->nodename, (const char *)rsi); + + send_reset (rsi); } - else if (connectmode == conf_node::C_ALWAYS) - establish_connection (); - } - break; - case vpn_packet::PT_AUTH_REQ: - if (auth_rate_limiter.can (rsi)) + break; + + case vpn_packet::PT_AUTH_RES: { - auth_req_packet *p = (auth_req_packet *) pkt; + auth_res_packet *p = (auth_res_packet *)pkt; - slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate); + slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); - if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) + if (p->chk_config ()) { if (p->prot_minor != PROTOCOL_MINOR) slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), conf->nodename, (const char *)rsi, PROTOCOL_MINOR, conf->nodename, p->prot_minor); - if (p->initiate) - send_auth_request (rsi, false); + rsachallenge chg; - rsachallenge k; - - if (0 > RSA_private_decrypt (sizeof (p->encr), - (unsigned char *)&p->encr, (unsigned char *)&k, - ::conf.rsa_key, RSA_PKCS1_OAEP_PADDING)) - slog (L_ERR, _("%s(%s): challenge illegal or corrupted"), - conf->nodename, (const char *)rsi); + if (!rsa_cache.find (p->id, chg)) + { + slog (L_ERR, _("%s(%s): unrequested auth response, ignoring."), + conf->nodename, (const char *)rsi); + break; + } else { - retry_cnt = 0; - establish_connection.set (NOW + 8); //? ;) - keepalive.reset (); - rekey.reset (); + crypto_ctx *cctx = new crypto_ctx (chg, 0); + + if (!p->hmac_chk (cctx)) + { + slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" + "could be an attack, or just corruption or a synchronization error."), + conf->nodename, (const char *)rsi); + break; + } + else + { + rsaresponse h; - delete ictx; - ictx = 0; + rsa_hash (p->id, chg, h); - delete octx; + if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) + { + prot_minor = p->prot_minor; - octx = new crypto_ctx (k, 1); - oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; + delete ictx; ictx = cctx; - conf->protocols = p->protocols; - send_auth_response (rsi, p->id, k); + iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid - break; + si = rsi; + protocol = rsi.prot; + + slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), + conf->nodename, (const char *)rsi, + is_direct ? "direct" : "forwarded", + p->prot_major, p->prot_minor); + + connection_established (); + + if (::conf.script_node_up) + { + run_script_cb *cb = new run_script_cb; + cb->set (this); + run_script_queued (cb, _("node-up command execution failed, continuing.")); + } + + break; + } + else + slog (L_ERR, _("%s(%s): sent and received challenge do not match."), + conf->nodename, (const char *)rsi); + } + + delete cctx; } } - - send_reset (rsi); } - break; + send_reset (rsi); + break; - case vpn_packet::PT_AUTH_RES: - { - auth_res_packet *p = (auth_res_packet *) pkt; + case vpn_packet::PT_DATA_COMPRESSED: +#if !ENABLE_COMPRESSION + send_reset (rsi); + break; +#endif - slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id); + case vpn_packet::PT_DATA_UNCOMPRESSED: - if (p->chk_config ()) + if (ictx && octx) { - if (p->prot_minor != PROTOCOL_MINOR) - slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), - conf->nodename, (const char *)rsi, - PROTOCOL_MINOR, conf->nodename, p->prot_minor); + vpndata_packet *p = (vpndata_packet *)pkt; - rsachallenge chg; - - if (!rsa_cache.find (p->id, chg)) - slog (L_ERR, _("%s(%s): unrequested auth response"), + if (!p->hmac_chk (ictx)) + slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" + "could be an attack, or just corruption or a synchronization error."), conf->nodename, (const char *)rsi); else { - crypto_ctx *cctx = new crypto_ctx (chg, 0); + u32 seqno; + tap_packet *d = p->unpack (this, seqno); + int seqclass = iseqno.seqno_classify (seqno); - if (!p->hmac_chk (cctx)) - slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" - "could be an attack, or just corruption or an synchronization error"), - conf->nodename, (const char *)rsi); - else + if (seqclass == 0) // ok { - rsaresponse h; + vpn->tap->send (d); - rsa_hash (p->id, chg, h); - - if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) + if (si != rsi) { - prot_minor = p->prot_minor; - - delete ictx; ictx = cctx; - - iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid - - si = rsi; - - rekey.set (NOW + ::conf.rekey); - keepalive.set (NOW + ::conf.keepalive); - - // send queued packets - while (tap_packet *p = queue.get ()) - { - send_data_packet (p); - delete p; - } - - connectmode = conf->connectmode; - - slog (L_INFO, _("%s(%s): %s connection established, protocol version %d.%d"), - conf->nodename, (const char *)rsi, - strprotocol (protocol), - p->prot_major, p->prot_minor); - - if (::conf.script_node_up) - run_script (run_script_cb (this, &connection::script_node_up), false); - - break; + // fast re-sync on source address changes, useful especially for tcp/ip + //if (last_si_change < ev_now () + 5.) + // { + slog (L_INFO, _("%s(%s): changing socket address to %s."), + conf->nodename, (const char *)si, (const char *)rsi); + + si = rsi; + // } + //else + // slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."), + // conf->nodename, (const char *)si, (const char *)rsi); } - else - slog (L_ERR, _("%s(%s): sent and received challenge do not match"), - conf->nodename, (const char *)rsi); + } + else if (seqclass == 1) // far history + slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). " + "possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1); + else if (seqclass == 2) // in-window duplicate, happens often on wireless + slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). " + "possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1); + else if (seqclass == 3) // reset + { + slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). " + "probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1); + send_reset (rsi); } - delete cctx; + delete d; + break; } } - } - send_reset (rsi); - break; - - case vpn_packet::PT_DATA_COMPRESSED: -#if !ENABLE_COMPRESSION - send_reset (rsi); - break; -#endif - - case vpn_packet::PT_DATA_UNCOMPRESSED: - - if (ictx && octx) - { - vpndata_packet *p = (vpndata_packet *)pkt; - - if (rsi == si) - { - if (!p->hmac_chk (ictx)) - slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" - "could be an attack, or just corruption or an synchronization error"), - conf->nodename, (const char *)rsi); - else - { - u32 seqno; - tap_packet *d = p->unpack (this, seqno); - - if (iseqno.recv_ok (seqno)) - { - vpn->tap->send (d); - - if (p->dst () == 0) // re-broadcast - for (vpn::conns_vector::iterator i = vpn->conns.begin (); i != vpn->conns.end (); ++i) - { - connection *c = *i; - - if (c->conf != THISNODE && c->conf != conf) - c->inject_data_packet (d); - } - - delete d; - - break; - } - } - } - else - slog (L_ERR, _("received data packet from unknown source %s"), (const char *)rsi); - } + send_reset (rsi); + break; - send_reset (rsi); - break; + case vpn_packet::PT_CONNECT_REQ: + if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) + { + connect_req_packet *p = (connect_req_packet *) pkt; - case vpn_packet::PT_CONNECT_REQ: - if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) - { - connect_req_packet *p = (connect_req_packet *) pkt; + if (p->id > 0 && p->id <= vpn->conns.size ()) + { + connection *c = vpn->conns[p->id - 1]; + conf->protocols = p->protocols; - assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything - conf->protocols = p->protocols; - connection *c = vpn->conns[p->id - 1]; + slog (L_TRACE, "%s >> PT_CONNECT_REQ(%s) [%d]", + conf->nodename, vpn->conns[p->id - 1]->conf->nodename, c->ictx && c->octx); - slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n", - conf->id, p->id, c->ictx && c->octx); + if (c->ictx && c->octx) + { + // send connect_info packets to both sides, in case one is + // behind a nat firewall (or both ;) + c->send_connect_info (conf->id, si, conf->protocols); + send_connect_info (c->conf->id, c->si, c->conf->protocols); + } + else + c->establish_connection (); + } + else + slog (L_WARN, + _("received authenticated connection request from unknown node #%d, config file mismatch?"), + p->id); + } - if (c->ictx && c->octx) - { - // send connect_info packets to both sides, in case one is - // behind a nat firewall (or both ;) - c->send_connect_info (conf->id, si, conf->protocols); - send_connect_info (c->conf->id, c->si, c->conf->protocols); - } - } + break; - break; + case vpn_packet::PT_CONNECT_INFO: + if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) + { + connect_info_packet *p = (connect_info_packet *)pkt; - case vpn_packet::PT_CONNECT_INFO: - if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) - { - connect_info_packet *p = (connect_info_packet *) pkt; + if (p->id > 0 && p->id <= vpn->conns.size ()) + { + connection *c = vpn->conns[p->id - 1]; - assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything - conf->protocols = p->protocols; - connection *c = vpn->conns[p->id - 1]; + c->conf->protocols = p->protocols; + protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); + p->si.upgrade_protocol (protocol, c->conf); - slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)", - conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx); + slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s) [%d]", + conf->nodename, vpn->conns[p->id - 1]->conf->nodename, + (const char *)p->si, !c->ictx && !c->octx); - c->send_auth_request (p->si, true); - } + const sockinfo &dsi = forward_si (p->si); - break; + if (dsi.valid ()) + c->send_auth_request (dsi, true); + } + else + slog (L_WARN, + _("received authenticated connection request from unknown node #%d, config file mismatch?"), + p->id); + } - default: - send_reset (rsi); - break; + break; + default: + send_reset (rsi); + break; } } -void connection::keepalive_cb (tstamp &ts) +inline void +connection::keepalive_cb (ev::timer &w, int revents) { - if (NOW >= last_activity + ::conf.keepalive + 30) + if (ev_now () >= last_activity + ::conf.keepalive + 30) { reset_connection (); establish_connection (); } - else if (NOW < last_activity + ::conf.keepalive) - ts = last_activity + ::conf.keepalive; + else if (ev_now () < last_activity + ::conf.keepalive) + w.start (last_activity + ::conf.keepalive - ev::now ()); else if (conf->connectmode != conf_node::C_ONDEMAND || THISNODE->connectmode != conf_node::C_ONDEMAND) { send_ping (si); - ts = NOW + 5; + w.start (5); } + else if (ev_now () < last_activity + ::conf.keepalive + 10) + // hold ondemand connections implicitly a few seconds longer + // should delete octx, though, or something like that ;) + w.start (last_activity + ::conf.keepalive + 10 - ev::now ()); else reset_connection (); } -void connection::connect_request (int id) +void connection::send_connect_request (int id) { connect_req_packet *p = new connect_req_packet (conf->id, id, conf->protocols); - slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", conf->id, id); + slog (L_TRACE, "%s << PT_CONNECT_REQ(%s)", + conf->nodename, vpn->conns[id - 1]->conf->nodename); p->hmac_set (octx); send_vpn_packet (p, si); delete p; } -void connection::script_node () +void connection::script_init_env (const char *ext) +{ + char *env; + asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env); + asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env); + asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext, + 0xfe, 0xfd, 0x80, 0x00, conf->id >> 8, + conf->id & 0xff); putenv (env); +} + +void connection::script_init_connect_env () { - vpn->script_if_up (0); + vpn->script_init_env (); char *env; asprintf (&env, "DESTID=%d", conf->id); putenv (env); @@ -1060,44 +1363,62 @@ asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); } -const char *connection::script_node_up (int) +inline const char * +connection::script_node_up () { - script_node (); + script_init_connect_env (); - putenv ("STATE=up"); + putenv ((char *)"STATE=up"); - return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; + char *filename; + asprintf (&filename, + "%s/%s", + confbase, + ::conf.script_node_up ? ::conf.script_node_up : "node-up"); + + return filename; } -const char *connection::script_node_down (int) +inline const char * +connection::script_node_down () { - script_node (); + script_init_connect_env (); - putenv ("STATE=down"); + putenv ((char *)"STATE=down"); - return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; -} + char *filename; + asprintf (&filename, + "%s/%s", + confbase, + ::conf.script_node_down ? ::conf.script_node_down : "node-down"); -// send a vpn packet out to other hosts -void -connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) -{ - if (protocol & PROT_IPv4) - vpn->send_ipv4_packet (pkt, si, tos); - else - vpn->send_udpv4_packet (pkt, si, tos); + return filename; } -connection::connection(struct vpn *vpn_) -: vpn(vpn_) -, rekey (this, &connection::rekey_cb) -, keepalive (this, &connection::keepalive_cb) -, establish_connection (this, &connection::establish_connection_cb) +connection::connection (struct vpn *vpn, conf_node *conf) +: vpn(vpn), conf(conf), +#if ENABLE_DNS + dns (0), +#endif + data_queue(conf->max_ttl, conf->max_queue + 1), + vpn_queue(conf->max_ttl, conf->max_queue + 1) { + rekey .set (this); + keepalive .set (this); + establish_connection.set (this); + + last_establish_attempt = 0.; octx = ictx = 0; - retry_cnt = 0; - connectmode = conf_node::C_ALWAYS; // initial setting + if (!conf->protocols) // make sure some protocol is enabled + conf->protocols = PROT_UDPv4; + + connectmode = conf->connectmode; + + // queue a dummy packet to force an initial connection attempt + if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED) + vpn_queue.put (new net_packet); + reset_connection (); }