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/* |
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vpn.C -- handle the protocol, encryption, handshaking etc. |
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Copyright (C) 2003-2008,2010,2011,2013 Marc Lehmann <gvpe@schmorp.de> |
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|
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This file is part of GVPE. |
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|
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GVPE is free software; you can redistribute it and/or modify it |
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under the terms of the GNU General Public License as published by the |
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Free Software Foundation; either version 3 of the License, or (at your |
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option) any later version. |
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|
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This program is distributed in the hope that it will be useful, but |
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WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General |
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Public License for more details. |
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|
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You should have received a copy of the GNU General Public License along |
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with this program; if not, see <http://www.gnu.org/licenses/>. |
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|
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Additional permission under GNU GPL version 3 section 7 |
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|
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If you modify this Program, or any covered work, by linking or |
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combining it with the OpenSSL project's OpenSSL library (or a modified |
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version of that library), containing parts covered by the terms of the |
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OpenSSL or SSLeay licenses, the licensors of this Program grant you |
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additional permission to convey the resulting work. Corresponding |
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Source for a non-source form of such a combination shall include the |
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source code for the parts of OpenSSL used as well as that of the |
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covered work. |
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*/ |
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|
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#include "config.h" |
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|
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#include <list> |
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|
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#include <cstdio> |
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#include <cstring> |
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#include <cstdlib> |
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|
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <sys/wait.h> |
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#include <sys/stat.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 <fcntl.h> |
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#include <sys/socket.h> |
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|
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#include "netcompat.h" |
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|
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#include "pidfile.h" |
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|
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#include "connection.h" |
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#include "util.h" |
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#include "vpn.h" |
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|
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using namespace std; |
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|
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vpn network; // THE vpn (bad design...) |
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|
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///////////////////////////////////////////////////////////////////////////// |
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|
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static void inline |
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set_tos (int fd, int &tos_prev, int tos) |
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{ |
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#if defined(SOL_IP) && defined(IP_TOS) |
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if (tos_prev == tos) |
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return; |
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|
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tos_prev = tos; |
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setsockopt (fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
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#endif |
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} |
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|
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void |
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vpn::script_init_env () |
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{ |
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// the tunnel device mtu should be the physical mtu - overhead |
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// the tricky part is rounding to the cipher key blocksize |
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int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - MAX_OVERHEAD; |
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mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
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mtu -= mtu % BLOCK_SIZE (CIPHER); // round |
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mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
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|
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char *env; |
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asprintf (&env, "CONFBASE=%s", confbase); putenv (env); |
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asprintf (&env, "IFNAME=%s", tap->interface ()); putenv (env); |
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asprintf (&env, "IFTYPE=%s", IFTYPE); putenv (env); |
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asprintf (&env, "IFSUBTYPE=%s", IFSUBTYPE); putenv (env); |
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asprintf (&env, "MTU=%d", mtu); putenv (env); |
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asprintf (&env, "NODES=%d", conns.size ()); putenv (env); |
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asprintf (&env, "NODEID=%d", THISNODE->id); putenv (env); |
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|
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conns [THISNODE->id - 1]->script_init_env (""); |
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|
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for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
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{ |
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char ext[16]; |
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snprintf (ext, 16, "_%d", (*c)->conf->id); |
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(*c)->script_init_env (ext); |
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} |
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} |
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|
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inline const char * |
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vpn::script_if_init () |
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{ |
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script_init_env (); |
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|
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return tap->if_up (); |
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} |
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|
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inline const char * |
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vpn::script_if_up () |
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{ |
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script_init_env (); |
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|
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return conf.config_filename (::conf.script_if_up, "if-up"); |
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} |
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|
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int |
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vpn::setup_socket (u8 prot, int family, int type, int proto) |
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{ |
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int fd = socket (family, type, proto); |
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|
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if (fd < 0) |
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{ |
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slog (L_ERR, _("unable to create %s socket: %s."), strprotocol (prot), strerror (errno)); |
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return fd; |
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} |
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|
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fcntl (fd, F_SETFL, O_NONBLOCK); |
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fcntl (fd, F_SETFD, FD_CLOEXEC); |
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|
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#ifdef SO_MARK |
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if (::conf.nfmark) |
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if (setsockopt (fd, SOL_SOCKET, SO_MARK, &::conf.nfmark, sizeof ::conf.nfmark)) |
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slog (L_WARN, _("unable to set nfmark on %s socket: %s"), strprotocol (prot), strerror (errno)); |
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#endif |
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|
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return fd; |
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} |
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|
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int |
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vpn::setup () |
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{ |
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int success = 0; |
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|
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ipv4_tos = -1; |
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ipv4_fd = -1; |
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|
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if (THISNODE->protocols & PROT_IPv4 && ::conf.ip_proto) |
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{ |
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ipv4_fd = setup_socket (PROT_IPv4, PF_INET, SOCK_RAW, ::conf.ip_proto); |
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|
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if (ipv4_fd < 0) |
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return -1; |
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|
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#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
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// this I really consider a linux bug. I am neither connected |
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// nor do I fragment myself. Linux still sets DF and doesn't |
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// fragment for me sometimes. |
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{ |
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int oval = IP_PMTUDISC_DONT; |
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setsockopt (ipv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
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} |
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#endif |
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|
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sockinfo si (THISNODE, PROT_IPv4); |
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|
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if (bind (ipv4_fd, si.sav4 (), si.salenv4 ())) |
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{ |
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slog (L_ERR, _("can't bind ipv4 socket on %s: %s, exiting."), (const char *)si, strerror (errno)); |
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return -1; |
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} |
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|
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ipv4_ev_watcher.start (ipv4_fd, EV_READ); |
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++success; |
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} |
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else |
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THISNODE->protocols &= ~PROT_IPv4; |
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|
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udpv4_tos = -1; |
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udpv4_fd = -1; |
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|
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if (THISNODE->protocols & PROT_UDPv4 && THISNODE->udp_port) |
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{ |
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udpv4_fd = setup_socket (PROT_UDPv4, PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
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|
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if (udpv4_fd < 0) |
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return -1; |
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|
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// standard daemon practise... |
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{ |
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int oval = 1; |
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setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
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} |
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|
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#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
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// this I really consider a linux bug. I am neither connected |
201 |
// nor do I fragment myself. Linux still sets DF and doesn't |
202 |
// fragment for me sometimes. |
203 |
{ |
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int oval = IP_PMTUDISC_DONT; |
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setsockopt (udpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
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} |
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#endif |
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|
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sockinfo si (THISNODE, PROT_UDPv4); |
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|
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if (bind (udpv4_fd, si.sav4 (), si.salenv4 ())) |
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{ |
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slog (L_ERR, _("can't bind udpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
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return -1; |
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} |
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|
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udpv4_ev_watcher.start (udpv4_fd, EV_READ); |
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++success; |
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} |
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else |
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THISNODE->protocols &= ~PROT_UDPv4; |
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|
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icmpv4_tos = -1; |
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icmpv4_fd = -1; |
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|
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#if ENABLE_ICMP |
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if (THISNODE->protocols & PROT_ICMPv4) |
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{ |
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icmpv4_fd = setup_socket (PROT_ICMPv4, PF_INET, SOCK_RAW, IPPROTO_ICMP); |
230 |
|
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if (icmpv4_fd < 0) |
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return -1; |
233 |
|
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#ifdef ICMP_FILTER |
235 |
{ |
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icmp_filter oval; |
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oval.data = 0xffffffff; |
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if (::conf.icmp_type < 32) |
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oval.data &= ~(1 << ::conf.icmp_type); |
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|
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setsockopt (icmpv4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval); |
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} |
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#endif |
244 |
|
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#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
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// this I really consider a linux bug. I am neither connected |
247 |
// nor do I fragment myself. Linux still sets DF and doesn't |
248 |
// fragment for me sometimes. |
249 |
{ |
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int oval = IP_PMTUDISC_DONT; |
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setsockopt (icmpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
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} |
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#endif |
254 |
|
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sockinfo si (THISNODE, PROT_ICMPv4); |
256 |
|
257 |
if (bind (icmpv4_fd, si.sav4 (), si.salenv4 ())) |
258 |
{ |
259 |
slog (L_ERR, _("can't bind icmpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
260 |
return -1; |
261 |
} |
262 |
|
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icmpv4_ev_watcher.start (icmpv4_fd, EV_READ); |
264 |
++success; |
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} |
266 |
#endif |
267 |
|
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tcpv4_fd = -1; |
269 |
|
270 |
#if ENABLE_TCP |
271 |
if (THISNODE->protocols & PROT_TCPv4 && THISNODE->tcp_port) |
272 |
{ |
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tcpv4_fd = setup_socket (PROT_TCPv4, PF_INET, SOCK_STREAM, IPPROTO_TCP); |
274 |
|
275 |
if (tcpv4_fd < 0) |
276 |
return -1; |
277 |
|
278 |
// standard daemon practise... |
279 |
{ |
280 |
int oval = 1; |
281 |
setsockopt (tcpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
282 |
} |
283 |
|
284 |
sockinfo si (THISNODE, PROT_TCPv4); |
285 |
|
286 |
if (bind (tcpv4_fd, si.sav4 (), si.salenv4 ())) |
287 |
{ |
288 |
slog (L_ERR, _("can't bind tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
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return -1; |
290 |
} |
291 |
|
292 |
if (listen (tcpv4_fd, 5)) |
293 |
{ |
294 |
slog (L_ERR, _("can't listen tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
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return -1; |
296 |
} |
297 |
|
298 |
tcpv4_ev_watcher.start (tcpv4_fd, EV_READ); |
299 |
++success; |
300 |
} |
301 |
else |
302 |
THISNODE->protocols &= ~PROT_TCPv4; |
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#endif |
304 |
|
305 |
dnsv4_tos = -1; |
306 |
dnsv4_fd = -1; |
307 |
|
308 |
#if ENABLE_DNS |
309 |
if (THISNODE->protocols & PROT_DNSv4) |
310 |
{ |
311 |
dns_forwarder.set (::conf.dns_forw_host, ::conf.dns_forw_port, PROT_DNSv4); |
312 |
|
313 |
dnsv4_fd = setup_socket (PROT_DNSv4, PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
314 |
|
315 |
if (dnsv4_fd < 0) |
316 |
return -1; |
317 |
|
318 |
# if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
319 |
// this I really consider a linux bug. I am neither connected |
320 |
// nor do I fragment myself. Linux still sets DF and doesn't |
321 |
// fragment for me sometimes. |
322 |
{ |
323 |
int oval = IP_PMTUDISC_DONT; |
324 |
setsockopt (dnsv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
325 |
} |
326 |
# endif |
327 |
|
328 |
// standard daemon practise... |
329 |
{ |
330 |
int oval = 1; |
331 |
setsockopt (dnsv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
332 |
} |
333 |
|
334 |
sockinfo si (THISNODE->dns_hostname, |
335 |
THISNODE->dns_hostname ? THISNODE->dns_port : 0, |
336 |
PROT_DNSv4); |
337 |
|
338 |
if (bind (dnsv4_fd, si.sav4 (), si.salenv4 ())) |
339 |
{ |
340 |
slog (L_ERR, _("can't bind dnsv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
341 |
return -1; |
342 |
} |
343 |
|
344 |
dnsv4_ev_watcher.start (dnsv4_fd, EV_READ); |
345 |
++success; |
346 |
} |
347 |
#endif |
348 |
|
349 |
///////////////////////////////////////////////////////////////////////////// |
350 |
|
351 |
if (!success) |
352 |
{ |
353 |
slog (L_ERR, _("no protocols enabled.")); |
354 |
return -1; |
355 |
} |
356 |
|
357 |
reconnect_all (); |
358 |
|
359 |
///////////////////////////////////////////////////////////////////////////// |
360 |
|
361 |
tap = new tap_device (); |
362 |
if (!tap) //D this, of course, never catches |
363 |
{ |
364 |
slog (L_ERR, _("cannot create network interface '%s'."), conf.ifname); |
365 |
return -1; |
366 |
} |
367 |
|
368 |
fcntl (tap->fd, F_SETFD, FD_CLOEXEC); |
369 |
|
370 |
run_script_cb cb; |
371 |
cb.set<vpn, &vpn::script_if_init> (this); |
372 |
|
373 |
if (tap->if_up () && |
374 |
!run_script (cb, true)) |
375 |
{ |
376 |
slog (L_ERR, _("interface initialization command '%s' failed."), |
377 |
tap->if_up ()); |
378 |
return -1; |
379 |
} |
380 |
|
381 |
cb.set<vpn, &vpn::script_if_up> (this); |
382 |
if (!run_script (cb, true)) |
383 |
{ |
384 |
slog (L_ERR, _("if-up command execution failed.")); |
385 |
return -1; |
386 |
} |
387 |
|
388 |
tap_ev_watcher.start (tap->fd, EV_READ); |
389 |
|
390 |
return 0; |
391 |
} |
392 |
|
393 |
bool |
394 |
vpn::drop_privileges () |
395 |
{ |
396 |
if (::conf.change_root) |
397 |
{ |
398 |
if (!strcmp (::conf.change_root, "/")) |
399 |
{ |
400 |
char dir [L_tmpnam]; |
401 |
if (!tmpnam (dir)) |
402 |
{ |
403 |
slog (L_CRIT, _("unable to create anonymous root path.")); |
404 |
return false; |
405 |
} |
406 |
|
407 |
if (mkdir (dir, 0700)) |
408 |
{ |
409 |
slog (L_CRIT, _("unable to create anonymous root directory.")); |
410 |
return false; |
411 |
} |
412 |
|
413 |
if (chdir (dir)) |
414 |
{ |
415 |
slog (L_CRIT, _("unable to change to anonymous root directory.")); |
416 |
return false; |
417 |
} |
418 |
|
419 |
if (rmdir (dir)) |
420 |
slog (L_ERR, _("unable to remove anonymous root directory, continuing.")); |
421 |
} |
422 |
else |
423 |
{ |
424 |
if (chdir (::conf.change_root)) |
425 |
{ |
426 |
slog (L_CRIT, _("%s: unable to change to specified root directory."), ::conf.change_root); |
427 |
return false; |
428 |
} |
429 |
} |
430 |
|
431 |
if (chroot (".")) |
432 |
{ |
433 |
slog (L_CRIT, _("unable to set new root directory.")); |
434 |
return false; |
435 |
} |
436 |
|
437 |
if (chdir ("/")) |
438 |
{ |
439 |
slog (L_CRIT, _("unable to set cwd to new root directory.")); |
440 |
return false; |
441 |
} |
442 |
} |
443 |
|
444 |
if (::conf.change_gid) |
445 |
if (setgid (::conf.change_gid)) |
446 |
{ |
447 |
slog (L_CRIT, _("unable to change group id to %d."), ::conf.change_gid); |
448 |
return false; |
449 |
} |
450 |
|
451 |
if (::conf.change_uid) |
452 |
if (setuid (::conf.change_uid)) |
453 |
{ |
454 |
slog (L_CRIT, _("unable to change user id to %d."), ::conf.change_uid); |
455 |
return false; |
456 |
} |
457 |
|
458 |
return true; |
459 |
} |
460 |
|
461 |
bool |
462 |
vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
463 |
{ |
464 |
set_tos (ipv4_fd, ipv4_tos, tos); |
465 |
sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
466 |
|
467 |
return true; |
468 |
} |
469 |
|
470 |
static u16 |
471 |
ipv4_checksum (u16 *data, unsigned int len) |
472 |
{ |
473 |
// use 32 bit accumulator and fold back carry bits at the end |
474 |
u32 sum = 0; |
475 |
|
476 |
while (len > 1) |
477 |
{ |
478 |
sum += *data++; |
479 |
len -= 2; |
480 |
} |
481 |
|
482 |
// odd byte left? |
483 |
if (len) |
484 |
sum += *(u8 *)data; |
485 |
|
486 |
// add back carry bits |
487 |
sum = (sum >> 16) + (sum & 0xffff); // lo += hi |
488 |
sum += (sum >> 16); // carry |
489 |
|
490 |
return ~sum; |
491 |
} |
492 |
|
493 |
#if ENABLE_ICMP |
494 |
bool |
495 |
vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
496 |
{ |
497 |
pkt->unshift_hdr (4); |
498 |
|
499 |
icmp_header *hdr = (icmp_header *)&((*pkt)[0]); |
500 |
hdr->type = ::conf.icmp_type; |
501 |
hdr->code = 255; |
502 |
hdr->checksum = 0; |
503 |
hdr->checksum = ipv4_checksum ((u16 *)hdr, pkt->len); |
504 |
|
505 |
set_tos (icmpv4_fd, icmpv4_tos, tos); |
506 |
sendto (icmpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
507 |
|
508 |
return true; |
509 |
} |
510 |
#endif |
511 |
|
512 |
bool |
513 |
vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
514 |
{ |
515 |
set_tos (udpv4_fd, udpv4_tos, tos); |
516 |
sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
517 |
|
518 |
return true; |
519 |
} |
520 |
|
521 |
void |
522 |
vpn::inject_data_packet (tap_packet *pkt, int dst) |
523 |
{ |
524 |
if (dst) |
525 |
{ |
526 |
// unicast |
527 |
if (dst != THISNODE->id) |
528 |
conns[dst - 1]->inject_data_packet (pkt); |
529 |
} |
530 |
else |
531 |
{ |
532 |
// broadcast, this is ugly, but due to the security policy |
533 |
// we have to connect to all hosts... |
534 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
535 |
if ((*c)->conf != THISNODE) |
536 |
(*c)->inject_data_packet (pkt); |
537 |
} |
538 |
} |
539 |
|
540 |
void |
541 |
vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
542 |
{ |
543 |
unsigned int src = pkt->src (); |
544 |
unsigned int dst = pkt->dst (); |
545 |
|
546 |
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d."), |
547 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
548 |
|
549 |
if (src == 0 || src > conns.size () |
550 |
|| dst > conns.size () |
551 |
|| pkt->typ () >= vpn_packet::PT_MAX) |
552 |
slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."), |
553 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ()); |
554 |
else |
555 |
{ |
556 |
connection *c = conns[src - 1]; |
557 |
|
558 |
if (dst == 0) |
559 |
slog (L_WARN, _("%s(%s): received broadcast (protocol violation)."), |
560 |
c->conf->nodename, (const char *)rsi); |
561 |
else if (dst != THISNODE->id) |
562 |
{ |
563 |
if (THISNODE->routerprio) |
564 |
// the tos setting gets lost here. who cares. |
565 |
conns[dst - 1]->inject_vpn_packet (pkt); |
566 |
else |
567 |
slog (L_WARN, |
568 |
_("%s(%s): request to forward packet to %s, but we are no router (config mismatch?)."), |
569 |
c->conf->nodename, (const char *)rsi, |
570 |
conns[dst - 1]->conf->nodename); |
571 |
} |
572 |
else |
573 |
c->recv_vpn_packet (pkt, rsi); |
574 |
} |
575 |
} |
576 |
|
577 |
bool |
578 |
vpn::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
579 |
{ |
580 |
switch (si.prot) |
581 |
{ |
582 |
case PROT_IPv4: |
583 |
return send_ipv4_packet (pkt, si, tos); |
584 |
|
585 |
case PROT_UDPv4: |
586 |
return send_udpv4_packet (pkt, si, tos); |
587 |
|
588 |
#if ENABLE_TCP |
589 |
case PROT_TCPv4: |
590 |
return send_tcpv4_packet (pkt, si, tos); |
591 |
#endif |
592 |
#if ENABLE_ICMP |
593 |
case PROT_ICMPv4: |
594 |
return send_icmpv4_packet (pkt, si, tos); |
595 |
#endif |
596 |
#if ENABLE_DNS |
597 |
case PROT_DNSv4: |
598 |
return send_dnsv4_packet (pkt, si, tos); |
599 |
#endif |
600 |
default: |
601 |
slog (L_CRIT, _("%s: FATAL: trying to send packet with unsupported protocol."), (const char *)si); |
602 |
} |
603 |
|
604 |
return false; |
605 |
} |
606 |
|
607 |
inline void |
608 |
vpn::ipv4_ev (ev::io &w, int revents) |
609 |
{ |
610 |
if (revents & EV_READ) |
611 |
{ |
612 |
vpn_packet *pkt = new vpn_packet; |
613 |
struct sockaddr_in sa; |
614 |
socklen_t sa_len = sizeof (sa); |
615 |
int len; |
616 |
|
617 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
618 |
|
619 |
sockinfo si(sa, PROT_IPv4); |
620 |
|
621 |
if (len > 0) |
622 |
{ |
623 |
pkt->len = len; |
624 |
|
625 |
// raw sockets deliver the ipv4 header, but don't expect it on sends |
626 |
pkt->skip_hdr (pkt->ipv4_hdr_len ()); |
627 |
|
628 |
recv_vpn_packet (pkt, si); |
629 |
} |
630 |
else |
631 |
{ |
632 |
// probably ECONNRESET or somesuch |
633 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
634 |
} |
635 |
|
636 |
delete pkt; |
637 |
} |
638 |
else |
639 |
{ |
640 |
slog (L_ERR, |
641 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
642 |
revents); |
643 |
exit (EXIT_FAILURE); |
644 |
} |
645 |
} |
646 |
|
647 |
#if ENABLE_ICMP |
648 |
inline void |
649 |
vpn::icmpv4_ev (ev::io &w, int revents) |
650 |
{ |
651 |
if (revents & EV_READ) |
652 |
{ |
653 |
vpn_packet *pkt = new vpn_packet; |
654 |
struct sockaddr_in sa; |
655 |
socklen_t sa_len = sizeof (sa); |
656 |
int len; |
657 |
|
658 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
659 |
|
660 |
sockinfo si(sa, PROT_ICMPv4); |
661 |
|
662 |
if (len > 0) |
663 |
{ |
664 |
pkt->len = len; |
665 |
|
666 |
icmp_header *hdr = (icmp_header *)&((*pkt)[IP_OVERHEAD]); |
667 |
|
668 |
if (hdr->type == ::conf.icmp_type |
669 |
&& hdr->code == 255) |
670 |
{ |
671 |
// raw sockets deliver the ipv4, but don't expect it on sends |
672 |
// this is slow, but... |
673 |
pkt->skip_hdr (pkt->ipv4_hdr_len () + (ICMP_OVERHEAD - IP_OVERHEAD)); |
674 |
|
675 |
recv_vpn_packet (pkt, si); |
676 |
} |
677 |
} |
678 |
else |
679 |
{ |
680 |
// probably ECONNRESET or somesuch |
681 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
682 |
} |
683 |
|
684 |
delete pkt; |
685 |
} |
686 |
else |
687 |
{ |
688 |
slog (L_ERR, |
689 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
690 |
revents); |
691 |
exit (EXIT_FAILURE); |
692 |
} |
693 |
} |
694 |
#endif |
695 |
|
696 |
inline void |
697 |
vpn::udpv4_ev (ev::io &w, int revents) |
698 |
{ |
699 |
if (revents & EV_READ) |
700 |
{ |
701 |
vpn_packet *pkt = new vpn_packet; |
702 |
struct sockaddr_in sa; |
703 |
socklen_t sa_len = sizeof (sa); |
704 |
int len; |
705 |
|
706 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
707 |
|
708 |
sockinfo si(sa, PROT_UDPv4); |
709 |
|
710 |
if (len > 0) |
711 |
{ |
712 |
pkt->len = len; |
713 |
|
714 |
recv_vpn_packet (pkt, si); |
715 |
} |
716 |
else |
717 |
{ |
718 |
// probably ECONNRESET or somesuch |
719 |
slog (L_DEBUG, _("%s: fd %d, %s."), (const char *)si, w.fd, strerror (errno)); |
720 |
} |
721 |
|
722 |
delete pkt; |
723 |
} |
724 |
else |
725 |
{ |
726 |
slog (L_ERR, |
727 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
728 |
revents); |
729 |
exit (EXIT_FAILURE); |
730 |
} |
731 |
} |
732 |
|
733 |
inline void |
734 |
vpn::tap_ev (ev::io &w, int revents) |
735 |
{ |
736 |
if (revents & EV_READ) |
737 |
{ |
738 |
/* process data */ |
739 |
tap_packet *pkt; |
740 |
|
741 |
pkt = tap->recv (); |
742 |
|
743 |
if (!pkt) |
744 |
return; |
745 |
|
746 |
if (pkt->len > 14) |
747 |
{ |
748 |
int dst = mac2id (pkt->dst); |
749 |
int src = mac2id (pkt->src); |
750 |
|
751 |
if (src != THISNODE->id) |
752 |
{ |
753 |
slog (L_ERR, _("FATAL: tap packet not originating on current node received (if-up script not working properly?), exiting.")); |
754 |
exit (EXIT_FAILURE); |
755 |
} |
756 |
|
757 |
if (dst == THISNODE->id) |
758 |
{ |
759 |
slog (L_ERR, _("FATAL: tap packet destined for current node received, exiting.")); |
760 |
exit (EXIT_FAILURE); |
761 |
} |
762 |
|
763 |
if (dst > conns.size ()) |
764 |
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
765 |
else |
766 |
inject_data_packet (pkt, dst); |
767 |
} |
768 |
|
769 |
delete pkt; |
770 |
} |
771 |
else |
772 |
abort (); |
773 |
} |
774 |
|
775 |
inline void |
776 |
vpn::event_cb (ev::timer &w, int) |
777 |
{ |
778 |
if (events) |
779 |
{ |
780 |
if (events & EVENT_SHUTDOWN) |
781 |
{ |
782 |
slog (L_INFO, _("preparing shutdown...")); |
783 |
|
784 |
shutdown_all (); |
785 |
remove_pid (conf.pidfilename); |
786 |
slog (L_INFO, _("exiting.")); |
787 |
exit (EXIT_SUCCESS); |
788 |
} |
789 |
|
790 |
if (events & EVENT_RECONNECT) |
791 |
{ |
792 |
slog (L_INFO, _("forced reconnect.")); |
793 |
|
794 |
reconnect_all (); |
795 |
} |
796 |
|
797 |
events = 0; |
798 |
} |
799 |
} |
800 |
|
801 |
void |
802 |
vpn::shutdown_all () |
803 |
{ |
804 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
805 |
(*c)->shutdown (); |
806 |
} |
807 |
|
808 |
void |
809 |
vpn::reconnect_all () |
810 |
{ |
811 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
812 |
delete *c; |
813 |
|
814 |
conns.clear (); |
815 |
|
816 |
connection_init (); |
817 |
|
818 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); i != conf.nodes.end (); ++i) |
819 |
conns.push_back (new connection (this, *i)); |
820 |
|
821 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
822 |
(*c)->establish_connection (); |
823 |
} |
824 |
|
825 |
bool |
826 |
vpn::can_direct (conf_node *src, conf_node *dst) const |
827 |
{ |
828 |
return src != dst |
829 |
&& src->may_direct (dst) |
830 |
&& dst->may_direct (src) |
831 |
&& (((src->protocols & dst->protocols) && src->connectmode == conf_node::C_ALWAYS) |
832 |
|| (src->protocols & dst->connectable_protocols ())); |
833 |
} |
834 |
|
835 |
// only works for indirect and routed connections: find a router |
836 |
// from THISNODE to dst |
837 |
connection * |
838 |
vpn::find_router_for (const connection *dst) |
839 |
{ |
840 |
connection *router = 0; |
841 |
|
842 |
// first try to find a router with a direct connection, route there |
843 |
// regardless of any other considerations. |
844 |
{ |
845 |
u32 prio = 1; |
846 |
|
847 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
848 |
{ |
849 |
connection *c = *i; |
850 |
|
851 |
if (c->conf->routerprio > prio |
852 |
&& c->conf != THISNODE |
853 |
&& can_direct (c->conf, dst->conf) |
854 |
&& c->ictx && c->octx) |
855 |
{ |
856 |
prio = c->conf->routerprio; |
857 |
router = c; |
858 |
} |
859 |
} |
860 |
} |
861 |
|
862 |
if (router) |
863 |
return router; |
864 |
|
865 |
// second try find the router with the highest priority, higher than ours |
866 |
{ |
867 |
u32 prio = THISNODE->routerprio ? THISNODE->routerprio : 1; |
868 |
|
869 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
870 |
{ |
871 |
connection *c = *i; |
872 |
|
873 |
if (c->conf->routerprio > prio |
874 |
&& c != dst |
875 |
&& c->conf != THISNODE |
876 |
&& c->ictx && c->octx) |
877 |
{ |
878 |
prio = c->conf->routerprio; |
879 |
router = c; |
880 |
} |
881 |
} |
882 |
} |
883 |
|
884 |
return router; |
885 |
} |
886 |
|
887 |
void |
888 |
vpn::connection_established (connection *c) |
889 |
{ |
890 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
891 |
{ |
892 |
connection *o = *i; |
893 |
|
894 |
if (o->si.valid () |
895 |
&& c->si != o->si |
896 |
&& c == find_router_for (o) |
897 |
&& !can_direct (THISNODE, o->conf)) |
898 |
{ |
899 |
slog (L_DEBUG, _("%s: can now route packets via %s, re-keying connection."), |
900 |
o->conf->nodename, c->conf->nodename); |
901 |
o->rekey (); |
902 |
} |
903 |
} |
904 |
} |
905 |
|
906 |
void |
907 |
vpn::send_connect_request (connection *c) |
908 |
{ |
909 |
connection *r = find_router_for (c); |
910 |
|
911 |
if (r) |
912 |
{ |
913 |
slog (L_TRACE, _("%s: no address known, sending mediated connection request via %s."), |
914 |
c->conf->nodename, r->conf->nodename); |
915 |
r->send_connect_request (c->conf->id); |
916 |
} |
917 |
else |
918 |
slog (L_DEBUG, _("%s: no way to connect and no router found: unable to connect at this time."), |
919 |
c->conf->nodename); |
920 |
} |
921 |
|
922 |
void |
923 |
connection::dump_status () |
924 |
{ |
925 |
slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id); |
926 |
slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"), |
927 |
connectmode, conf->connectmode, (const char *)si, (int)prot_minor); |
928 |
slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"), |
929 |
(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt); |
930 |
} |
931 |
|
932 |
void |
933 |
vpn::dump_status () |
934 |
{ |
935 |
slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)ev_now ()); |
936 |
|
937 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
938 |
(*c)->dump_status (); |
939 |
|
940 |
slog (L_NOTICE, _("END status dump")); |
941 |
} |
942 |
|
943 |
vpn::vpn (void) |
944 |
{ |
945 |
event .set<vpn, &vpn::event_cb > (this); |
946 |
udpv4_ev_watcher .set<vpn, &vpn::udpv4_ev > (this); |
947 |
ipv4_ev_watcher .set<vpn, &vpn::ipv4_ev > (this); |
948 |
#if ENABLE_TCP |
949 |
tcpv4_ev_watcher .set<vpn, &vpn::tcpv4_ev > (this); |
950 |
#endif |
951 |
#if ENABLE_ICMP |
952 |
icmpv4_ev_watcher.set<vpn, &vpn::icmpv4_ev> (this); |
953 |
#endif |
954 |
#if ENABLE_DNS |
955 |
dnsv4_ev_watcher .set<vpn, &vpn::dnsv4_ev > (this); |
956 |
#endif |
957 |
tap_ev_watcher .set<vpn, &vpn::tap_ev > (this); |
958 |
} |
959 |
|
960 |
vpn::~vpn () |
961 |
{ |
962 |
} |
963 |
|