--- gvpe/src/connection.C 2003/04/02 21:02:25 1.4 +++ gvpe/src/connection.C 2003/08/08 07:52:26 1.13 @@ -149,7 +149,7 @@ ////////////////////////////////////////////////////////////////////////////// -void pkt_queue::put (tap_packet *p) +void pkt_queue::put (net_packet *p) { if (queue[i]) { @@ -162,9 +162,9 @@ i = (i + 1) % QUEUEDEPTH; } -tap_packet *pkt_queue::get () +net_packet *pkt_queue::get () { - tap_packet *p = queue[j]; + net_packet *p = queue[j]; if (p) { @@ -199,9 +199,10 @@ // 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 + static const double ALPHA = 1. - 1. / 180.; // allow bursts + static const double CUTOFF = 10.; // one event every CUTOFF seconds + static const double EXPIRE = CUTOFF * 30.; // expire entries after this time + static const double MAXDIF = CUTOFF * (1. / (1. - ALPHA)); // maximum diff /count value bool can (const sockinfo &si) { return can((u32)si.host); } bool can (u32 host); @@ -227,7 +228,7 @@ ri.host = host; ri.pcnt = 1.; - ri.diff = CUTOFF * (1. / (1. - ALPHA)); + ri.diff = MAXDIF; ri.last = NOW; push_front (ri); @@ -244,9 +245,16 @@ ri.last = NOW; - bool send = ri.diff / ri.pcnt > CUTOFF; + double dif = ri.diff / ri.pcnt; - if (send) + bool send = dif > CUTOFF; + + if (dif > MAXDIF) + { + ri.pcnt = 1.; + ri.diff = MAXDIF; + } + else if (send) ri.pcnt++; push_front (ri); @@ -287,9 +295,9 @@ 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; @@ -548,9 +556,79 @@ ///////////////////////////////////////////////////////////////////////////// void -connection::reset_dstaddr () +connection::connection_established () { - si.set (conf); + if (ictx && octx) + { + connectmode = conf->connectmode; + + rekey.start (NOW + ::conf.rekey); + keepalive.start (NOW + ::conf.keepalive); + + // send queued packets + if (ictx && octx) + { + while (tap_packet *p = (tap_packet *)data_queue.get ()) + { + send_data_packet (p); + delete p; + } + + while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) + { + send_vpn_packet (p, si, IPTOS_RELIABILITY); + delete p; + } + } + } + else + { + retry_cnt = 0; + establish_connection.start (NOW + 5); + keepalive.reset (); + rekey.reset (); + } +} + +void +connection::reset_si () +{ + 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; + + si.set (conf, protocol); +} + +// ensure sockinfo is valid, forward if necessary +const sockinfo & +connection::forward_si (const sockinfo &si) const +{ + if (!si.valid ()) + { + connection *r = vpn->find_router (); + + if (r) + { + slog (L_DEBUG, _("%s: no common protocol, trying indirectly through %s"), + conf->nodename, r->conf->nodename); + return r->si; + } + else + slog (L_DEBUG, _("%s: node unreachable, no common protocol"), + conf->nodename); + } + + return si; +} + +void +connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) +{ + if (!vpn->send_vpn_packet (pkt, si, tos)) + reset_connection (); } void @@ -583,31 +661,20 @@ { 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; + rsachallenge chg; - rsa_cache.gen (pkt->id, 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"); + 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"); - slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)si); + slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (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 @@ -658,19 +725,22 @@ w.at = NOW + retry_int; - if (conf->hostname) + reset_si (); + + if (si.prot && !si.host) + vpn->send_connect_request (conf->id); + else { - reset_dstaddr (); - if (si.host && auth_rate_limiter.can (si)) - { - if (retry_cnt < 4) - send_auth_request (si, true); - else - send_ping (si, 0); - } + const sockinfo &dsi = forward_si (si); + + if (dsi.valid () && auth_rate_limiter.can (dsi)) + { + if (retry_cnt < 4) + send_auth_request (dsi, true); + else + send_ping (dsi, 0); + } } - else - vpn->connect_request (conf->id); } } @@ -723,6 +793,7 @@ vpndata_packet *p = new vpndata_packet; int tos = 0; + // I am not hilarious about peeking into packets, but so be it. if (conf->inherit_tos && (*pkt)[12] == 0x08 && (*pkt)[13] == 0x00 // IP && ((*pkt)[14] & 0xf0) == 0x40) // IPv4 @@ -745,7 +816,19 @@ else { if (!broadcast)//DDDD - queue.put (new tap_packet (*pkt)); + data_queue.put (new tap_packet (*pkt)); + + 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 (new vpn_packet (*pkt)); establish_connection (); } @@ -821,22 +904,17 @@ conf->nodename, (const char *)rsi); else { - retry_cnt = 0; - establish_connection.set (NOW + 8); //? ;) - keepalive.reset (); - rekey.reset (); - - delete ictx; - ictx = 0; - delete octx; octx = new crypto_ctx (k, 1); oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; conf->protocols = p->protocols; + send_auth_response (rsi, p->id, k); + connection_established (); + break; } } @@ -862,8 +940,11 @@ rsachallenge chg; if (!rsa_cache.find (p->id, chg)) - slog (L_ERR, _("%s(%s): unrequested auth response"), - conf->nodename, (const char *)rsi); + { + slog (L_ERR, _("%s(%s): unrequested auth response"), + conf->nodename, (const char *)rsi); + break; + } else { crypto_ctx *cctx = new crypto_ctx (chg, 0); @@ -887,22 +968,12 @@ iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid si = rsi; + protocol = rsi.prot; - rekey.set (NOW + ::conf.rekey); - keepalive.set (NOW + ::conf.keepalive); + connection_established (); - // 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"), + slog (L_INFO, _("%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) @@ -935,38 +1006,42 @@ { 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 { - 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); + u32 seqno; + tap_packet *d = p->unpack (this, seqno); - if (iseqno.recv_ok (seqno)) - { - vpn->tap->send (d); + 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 (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); - } + if (c->conf != THISNODE && c->conf != conf) + c->inject_data_packet (d); + } - delete d; + if (si != rsi) + { + // fast re-sync on conneciton changes, useful especially for tcp/ip + si = rsi; - break; + slog (L_INFO, _("%s(%s): socket address changed to %s"), + conf->nodename, (const char *)si, (const char *)rsi); } + + delete d; + + break; } } - else - slog (L_ERR, _("received data packet from unknown source %s"), (const char *)rsi); } send_reset (rsi); @@ -978,8 +1053,8 @@ connect_req_packet *p = (connect_req_packet *) pkt; 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]; + conf->protocols = p->protocols; slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n", conf->id, p->id, c->ictx && c->octx); @@ -991,6 +1066,8 @@ c->send_connect_info (conf->id, si, conf->protocols); send_connect_info (c->conf->id, c->si, c->conf->protocols); } + else + c->establish_connection (); } break; @@ -1001,13 +1078,20 @@ connect_info_packet *p = (connect_info_packet *) pkt; 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); - c->send_auth_request (p->si, true); + const sockinfo &dsi = forward_si (p->si); + + if (dsi.valid ()) + c->send_auth_request (dsi, true); } break; @@ -1033,11 +1117,15 @@ send_ping (si); w.at = NOW + 5; } + else if (NOW < last_activity + ::conf.keepalive + 10) + // hold ondemand connections implicitly a few seconds longer + // should delete octx, though, or something like that ;) + w.at = last_activity + ::conf.keepalive + 10; 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); @@ -1077,26 +1165,6 @@ return ::conf.script_node_up ? ::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) -{ - switch (protocol) - { - case PROT_IPv4: - vpn->send_ipv4_packet (pkt, si, tos); - break; - - case PROT_UDPv4: - vpn->send_udpv4_packet (pkt, si, tos); - break; - - case PROT_TCPv4: - vpn->send_tcpv4_packet (pkt, si, tos); - break; - } -} - connection::connection(struct vpn *vpn_) : vpn(vpn_) , rekey (this, &connection::rekey_cb)