--- gvpe/src/vpn.C 2003/04/08 03:25:35 1.10 +++ gvpe/src/vpn.C 2004/07/25 18:11:40 1.25 @@ -1,5 +1,6 @@ /* vpn.C -- handle the protocol, encryption, handshaking etc. + Copyright (C) 2003-2004 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 @@ -20,20 +21,20 @@ #include -#include -#include #include +#include +#include #include #include -#include #include #include #include #include -#include -#include -#include +#include +#include + +#include "netcompat.h" #include "pidfile.h" @@ -41,6 +42,8 @@ #include "util.h" #include "vpn.h" +vpn network; // THE vpn (bad design...) + ///////////////////////////////////////////////////////////////////////////// const char *vpn::script_if_up () @@ -53,16 +56,13 @@ mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again char *env; - asprintf (&env, "CONFBASE=%s", confbase); - putenv (env); - asprintf (&env, "NODENAME=%s", THISNODE->nodename); - putenv (env); - asprintf (&env, "NODEID=%d", THISNODE->id); - putenv (env); - asprintf (&env, "IFNAME=%s", tap->interface ()); - putenv (env); - asprintf (&env, "MTU=%d", mtu); - putenv (env); + asprintf (&env, "CONFBASE=%s", confbase); putenv (env); + asprintf (&env, "NODENAME=%s", THISNODE->nodename); putenv (env); + asprintf (&env, "NODEID=%d", THISNODE->id); putenv (env); + asprintf (&env, "IFNAME=%s", tap->interface ()); putenv (env); + asprintf (&env, "IFTYPE=%s", IFTYPE); putenv (env); + asprintf (&env, "IFSUBTYPE=%s", IFSUBTYPE); putenv (env); + asprintf (&env, "MTU=%d", mtu); putenv (env); asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x", 0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8, THISNODE->id & 0xff); @@ -83,7 +83,9 @@ if (ipv4_fd < 0) return -1; -#ifdef IP_MTU_DISCOVER + fcntl (ipv4_fd, F_SETFL, O_NONBLOCK); + +#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) // this I really consider a linux bug. I am neither connected // nor do I fragment myself. Linux still sets DF and doesn't // fragment for me sometimes. @@ -98,10 +100,10 @@ if (bind (ipv4_fd, si.sav4 (), si.salenv4 ())) { slog (L_ERR, _("can't bind ipv4 socket on %s: %s"), (const char *)si, strerror (errno)); - exit (1); + exit (EXIT_FAILURE); } - ipv4_ev_watcher.start (ipv4_fd, POLLIN); + ipv4_ev_watcher.start (ipv4_fd, EVENT_READ); } udpv4_fd = -1; @@ -113,13 +115,15 @@ if (udpv4_fd < 0) return -1; + fcntl (udpv4_fd, F_SETFL, O_NONBLOCK); + // standard daemon practise... { int oval = 1; setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); } -#ifdef IP_MTU_DISCOVER +#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) // this I really consider a linux bug. I am neither connected // nor do I fragment myself. Linux still sets DF and doesn't // fragment for me sometimes. @@ -134,10 +138,10 @@ if (bind (udpv4_fd, si.sav4 (), si.salenv4 ())) { slog (L_ERR, _("can't bind udpv4 on %s: %s"), (const char *)si, strerror (errno)); - exit (1); + exit (EXIT_FAILURE); } - udpv4_ev_watcher.start (udpv4_fd, POLLIN); + udpv4_ev_watcher.start (udpv4_fd, EVENT_READ); } icmpv4_fd = -1; @@ -150,6 +154,8 @@ if (icmpv4_fd < 0) return -1; + fcntl (icmpv4_fd, F_SETFL, O_NONBLOCK); + #ifdef ICMP_FILTER { icmp_filter oval; @@ -161,7 +167,7 @@ } #endif -#ifdef IP_MTU_DISCOVER +#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) // this I really consider a linux bug. I am neither connected // nor do I fragment myself. Linux still sets DF and doesn't // fragment for me sometimes. @@ -176,10 +182,10 @@ if (bind (icmpv4_fd, si.sav4 (), si.salenv4 ())) { slog (L_ERR, _("can't bind icmpv4 on %s: %s"), (const char *)si, strerror (errno)); - exit (1); + exit (EXIT_FAILURE); } - icmpv4_ev_watcher.start (icmpv4_fd, POLLIN); + icmpv4_ev_watcher.start (icmpv4_fd, EVENT_READ); } #endif @@ -193,6 +199,8 @@ if (tcpv4_fd < 0) return -1; + fcntl (tcpv4_fd, F_SETFL, O_NONBLOCK); + // standard daemon practise... { int oval = 1; @@ -204,16 +212,42 @@ if (bind (tcpv4_fd, si.sav4 (), si.salenv4 ())) { slog (L_ERR, _("can't bind tcpv4 on %s: %s"), (const char *)si, strerror (errno)); - exit (1); + exit (EXIT_FAILURE); } if (listen (tcpv4_fd, 5)) { slog (L_ERR, _("can't listen tcpv4 on %s: %s"), (const char *)si, strerror (errno)); - exit (1); + exit (EXIT_FAILURE); } - tcpv4_ev_watcher.start (tcpv4_fd, POLLIN); + tcpv4_ev_watcher.start (tcpv4_fd, EVENT_READ); + } +#endif + +#if ENABLE_DNS + if (THISNODE->protocols & PROT_DNSv4) + { + dnsv4_fd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP); + + if (dnsv4_fd < 0) + return -1; + + // standard daemon practise... + { + int oval = 1; + setsockopt (tcpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); + } + + sockinfo si (THISNODE, PROT_DNSv4); + + if (bind (dnsv4_fd, si.sav4 (), si.salenv4 ())) + { + slog (L_ERR, _("can't bind dnsv4 on %s: %s"), (const char *)si, strerror (errno)); + exit (EXIT_FAILURE); + } + + dnsv4_ev_watcher.start (dnsv4_fd, EVENT_READ); } #endif @@ -221,12 +255,12 @@ if (!tap) //D this, of course, never catches { slog (L_ERR, _("cannot create network interface '%s'"), conf.ifname); - exit (1); + exit (EXIT_FAILURE); } run_script (run_script_cb (this, &vpn::script_if_up), true); - tap_ev_watcher.start (tap->fd, POLLIN); + tap_ev_watcher.start (tap->fd, EVENT_READ); reconnect_all (); @@ -255,6 +289,11 @@ return send_icmpv4_packet (pkt, si, tos); #endif +#if ENABLE_DNS + case PROT_DNSv4: + return send_dnsv4_packet (pkt, si, tos); +#endif + default: slog (L_CRIT, _("%s: FATAL: trying to send packet with unsupported protocol"), (const char *)si); return false; @@ -264,7 +303,9 @@ bool vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) { +#if defined(SOL_IP) && defined(IP_TOS) setsockopt (ipv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); +#endif sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); return true; @@ -293,14 +334,17 @@ return ~sum; } +#if ENABLE_ICMP bool vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) { +#if defined(SOL_IP) && defined(IP_TOS) setsockopt (icmpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); +#endif pkt->unshift_hdr (4); - icmphdr *hdr = (icmphdr *)&((*pkt)[0]); + icmp_header *hdr = (icmp_header *)&((*pkt)[0]); hdr->type = ::conf.icmp_type; hdr->code = 255; hdr->checksum = 0; @@ -310,17 +354,39 @@ return true; } +#endif bool vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) { +#if defined(SOL_IP) && defined(IP_TOS) setsockopt (udpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); +#endif sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); return true; } void +vpn::inject_data_packet (tap_packet *pkt, int dst) +{ + if (dst) + { + // unicast + if (dst != THISNODE->id) + conns[dst - 1]->inject_data_packet (pkt); + } + else + { + // broadcast, this is ugly, but due to the security policy + // we have to connect to all hosts... + for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) + if ((*c)->conf != THISNODE) + (*c)->inject_data_packet (pkt, true); + } +} + +void vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) { unsigned int src = pkt->src (); @@ -341,10 +407,10 @@ { connection *c = conns[src - 1]; - if (dst == 0 && !THISNODE->routerprio) - slog (L_WARN, _("%s(%s): received broadcast, but we are no router"), + if (dst == 0) + slog (L_WARN, _("%s(%s): received broadcast (protocol violation)"), c->conf->nodename, (const char *)rsi); - else if (dst != 0 && dst != THISNODE->id) + else if (dst != THISNODE->id) { if (THISNODE->routerprio) // the tos setting gets lost here. who cares. @@ -363,7 +429,7 @@ void vpn::ipv4_ev (io_watcher &w, short revents) { - if (revents & (POLLIN | POLLERR)) + if (revents & EVENT_READ) { vpn_packet *pkt = new vpn_packet; struct sockaddr_in sa; @@ -392,25 +458,20 @@ delete pkt; } - else if (revents & POLLHUP) - { - // this cannot ;) happen on udp sockets - slog (L_ERR, _("FATAL: POLLHUP on ipv4 fd, terminating.")); - exit (1); - } else { slog (L_ERR, _("FATAL: unknown revents %08x in socket, terminating\n"), revents); - exit (1); + exit (EXIT_FAILURE); } } +#if ENABLE_ICMP void vpn::icmpv4_ev (io_watcher &w, short revents) { - if (revents & (POLLIN | POLLERR)) + if (revents & EVENT_READ) { vpn_packet *pkt = new vpn_packet; struct sockaddr_in sa; @@ -425,7 +486,7 @@ { pkt->len = len; - icmphdr *hdr = (icmphdr *)&((*pkt)[IP_OVERHEAD]); + icmp_header *hdr = (icmp_header *)&((*pkt)[IP_OVERHEAD]); if (hdr->type == ::conf.icmp_type && hdr->code == 255) @@ -445,25 +506,20 @@ delete pkt; } - else if (revents & POLLHUP) - { - // this cannot ;) happen on udp sockets - slog (L_ERR, _("FATAL: POLLHUP on icmpv4 fd, terminating.")); - exit (1); - } else { slog (L_ERR, _("FATAL: unknown revents %08x in socket, terminating\n"), revents); - exit (1); + exit (EXIT_FAILURE); } } +#endif void vpn::udpv4_ev (io_watcher &w, short revents) { - if (revents & (POLLIN | POLLERR)) + if (revents & EVENT_READ) { vpn_packet *pkt = new vpn_packet; struct sockaddr_in sa; @@ -488,77 +544,53 @@ delete pkt; } - else if (revents & POLLHUP) - { - // this cannot ;) happen on udp sockets - slog (L_ERR, _("FATAL: POLLHUP on udp v4 fd, terminating.")); - exit (1); - } else { slog (L_ERR, _("FATAL: unknown revents %08x in socket, terminating\n"), revents); - exit (1); + exit (EXIT_FAILURE); } } void vpn::tap_ev (io_watcher &w, short revents) { - if (revents & POLLIN) + if (revents & EVENT_READ) { /* process data */ tap_packet *pkt; pkt = tap->recv (); - int dst = mac2id (pkt->dst); - int src = mac2id (pkt->src); + if (!pkt) + return; - if (src != THISNODE->id) + if (pkt->len > 14) { - slog (L_ERR, _("FATAL: tap packet not originating on current node received, terminating.")); - exit (1); - } + int dst = mac2id (pkt->dst); + int src = mac2id (pkt->src); - if (dst == THISNODE->id) - { - slog (L_ERR, _("FATAL: tap packet destined for current node received, terminating.")); - exit (1); - } - - if (dst > conns.size ()) - slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); - else - { - if (dst) + if (src != THISNODE->id) { - // unicast - if (dst != THISNODE->id) - conns[dst - 1]->inject_data_packet (pkt); + slog (L_ERR, _("FATAL: tap packet not originating on current node received, exiting.")); + exit (EXIT_FAILURE); } - else - { - // broadcast, first check router, then self, then english - connection *router = find_router (); - if (router) - router->inject_data_packet (pkt, true); - else - for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) - if ((*c)->conf != THISNODE) - (*c)->inject_data_packet (pkt); + if (dst == THISNODE->id) + { + slog (L_ERR, _("FATAL: tap packet destined for current node received, exiting.")); + exit (EXIT_FAILURE); } + + if (dst > conns.size ()) + slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); + else + inject_data_packet (pkt, dst); } delete pkt; } - else if (revents & (POLLHUP | POLLERR)) - { - slog (L_ERR, _("FATAL: POLLHUP or POLLERR on network device fd, terminating.")); - exit (1); - } else abort (); } @@ -573,12 +605,9 @@ slog (L_INFO, _("preparing shutdown...")); shutdown_all (); - - remove_pid (pidfilename); - + remove_pid (conf.pidfilename); slog (L_INFO, _("terminating")); - - exit (0); + exit (EXIT_SUCCESS); } if (events & EVENT_RECONNECT) @@ -590,8 +619,6 @@ events = 0; } - - w.at = TSTAMP_CANCEL; } void @@ -633,9 +660,9 @@ connection *c = *i; if (c->conf->routerprio > prio - && c->connectmode == conf_node::C_ALWAYS - && c->conf != THISNODE - && c->ictx && c->octx) + && c->connectmode == conf_node::C_ALWAYS // so we don't drop the connection if in use + && c->ictx && c->octx + && c->conf != THISNODE) // redundant, since ictx==octx==0 always on thisnode { prio = c->conf->routerprio; router = c; @@ -654,7 +681,7 @@ else // no router found, aggressively connect to all routers for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) - if ((*i)->conf->routerprio) + if ((*i)->conf->routerprio && (*i)->conf != THISNODE) (*i)->establish_connection (); } @@ -691,6 +718,9 @@ #if ENABLE_ICMP , icmpv4_ev_watcher(this, &vpn::icmpv4_ev) #endif +#if ENABLE_DNS +, dnsv4_ev_watcher (this, &vpn::dnsv4_ev) +#endif , tap_ev_watcher (this, &vpn::tap_ev) { }