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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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///////////////////////////////////////////////////////////////////////////// |
63 |
|
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// hopefully temporary workaround for rare buffer full conditions |
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// if it happens, usually instantly retrying or retrying ~5ms later |
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// is good enough with current network technologies/kernels |
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|
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static ssize_t |
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xsendto (int fd, const void *buf, size_t len, int flags, |
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const struct sockaddr *sa, socklen_t salen) |
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{ |
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ssize_t res; |
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|
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for (int retry = 0; retry <= 13; ++retry) // ~100ms |
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{ |
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res = sendto (fd, buf, len, flags, sa, salen); |
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|
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if (res >= 0 || errno != ENOBUFS) |
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break; |
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|
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struct timespec ts = { 0, 1000 * retry }; |
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nanosleep (&ts, 0); |
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} |
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|
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return res; |
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} |
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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 |
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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 (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); |
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|
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if (icmpv4_fd < 0) |
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return -1; |
259 |
|
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#ifdef ICMP_FILTER |
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{ |
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icmp_filter oval; |
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oval.data = 0; |
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if (::conf.icmp_type < 32) |
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oval.data |= 1 << ::conf.icmp_type; |
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oval.data = ~oval.data; |
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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 |
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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 |
275 |
// fragment for me sometimes. |
276 |
{ |
277 |
int oval = IP_PMTUDISC_DONT; |
278 |
setsockopt (icmpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
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} |
280 |
#endif |
281 |
|
282 |
sockinfo si (THISNODE, PROT_ICMPv4); |
283 |
|
284 |
if (bind (icmpv4_fd, si.sav4 (), si.salenv4 ())) |
285 |
{ |
286 |
slog (L_ERR, _("can't bind icmpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
287 |
return -1; |
288 |
} |
289 |
|
290 |
icmpv4_ev_watcher.start (icmpv4_fd, EV_READ); |
291 |
++success; |
292 |
} |
293 |
#endif |
294 |
|
295 |
tcpv4_fd = -1; |
296 |
|
297 |
#if ENABLE_TCP |
298 |
if (THISNODE->protocols & PROT_TCPv4 && THISNODE->tcp_port) |
299 |
{ |
300 |
tcpv4_fd = setup_socket (PROT_TCPv4, PF_INET, SOCK_STREAM, IPPROTO_TCP); |
301 |
|
302 |
if (tcpv4_fd < 0) |
303 |
return -1; |
304 |
|
305 |
// standard daemon practise... |
306 |
{ |
307 |
int oval = 1; |
308 |
setsockopt (tcpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
309 |
} |
310 |
|
311 |
sockinfo si (THISNODE, PROT_TCPv4); |
312 |
|
313 |
if (bind (tcpv4_fd, si.sav4 (), si.salenv4 ())) |
314 |
{ |
315 |
slog (L_ERR, _("can't bind tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
316 |
return -1; |
317 |
} |
318 |
|
319 |
if (listen (tcpv4_fd, 5)) |
320 |
{ |
321 |
slog (L_ERR, _("can't listen tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
322 |
return -1; |
323 |
} |
324 |
|
325 |
tcpv4_ev_watcher.start (tcpv4_fd, EV_READ); |
326 |
++success; |
327 |
} |
328 |
else |
329 |
THISNODE->protocols &= ~PROT_TCPv4; |
330 |
#endif |
331 |
|
332 |
dnsv4_tos = -1; |
333 |
dnsv4_fd = -1; |
334 |
|
335 |
#if ENABLE_DNS |
336 |
if (THISNODE->protocols & PROT_DNSv4) |
337 |
{ |
338 |
dns_forwarder.set (::conf.dns_forw_host, ::conf.dns_forw_port, PROT_DNSv4); |
339 |
|
340 |
dnsv4_fd = setup_socket (PROT_DNSv4, PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
341 |
|
342 |
if (dnsv4_fd < 0) |
343 |
return -1; |
344 |
|
345 |
# if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
346 |
// this I really consider a linux bug. I am neither connected |
347 |
// nor do I fragment myself. Linux still sets DF and doesn't |
348 |
// fragment for me sometimes. |
349 |
{ |
350 |
int oval = IP_PMTUDISC_DONT; |
351 |
setsockopt (dnsv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
352 |
} |
353 |
# endif |
354 |
|
355 |
// standard daemon practise... |
356 |
{ |
357 |
int oval = 1; |
358 |
setsockopt (dnsv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
359 |
} |
360 |
|
361 |
sockinfo si (THISNODE->dns_hostname, |
362 |
THISNODE->dns_hostname ? THISNODE->dns_port : 0, |
363 |
PROT_DNSv4); |
364 |
|
365 |
if (bind (dnsv4_fd, si.sav4 (), si.salenv4 ())) |
366 |
{ |
367 |
slog (L_ERR, _("can't bind dnsv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
368 |
return -1; |
369 |
} |
370 |
|
371 |
dnsv4_ev_watcher.start (dnsv4_fd, EV_READ); |
372 |
++success; |
373 |
} |
374 |
#endif |
375 |
|
376 |
///////////////////////////////////////////////////////////////////////////// |
377 |
|
378 |
if (!success) |
379 |
{ |
380 |
slog (L_ERR, _("no protocols enabled.")); |
381 |
return -1; |
382 |
} |
383 |
|
384 |
reconnect_all (); |
385 |
|
386 |
///////////////////////////////////////////////////////////////////////////// |
387 |
|
388 |
tap = new tap_device (); |
389 |
if (!tap) //D this, of course, never catches |
390 |
{ |
391 |
slog (L_ERR, _("cannot create network interface '%s'."), conf.ifname); |
392 |
return -1; |
393 |
} |
394 |
|
395 |
fcntl (tap->fd, F_SETFD, FD_CLOEXEC); |
396 |
|
397 |
run_script_cb cb; |
398 |
cb.set<vpn, &vpn::script_if_init> (this); |
399 |
|
400 |
if (tap->if_up () && |
401 |
!run_script (cb, true)) |
402 |
{ |
403 |
slog (L_ERR, _("interface initialization command '%s' failed."), |
404 |
tap->if_up ()); |
405 |
return -1; |
406 |
} |
407 |
|
408 |
cb.set<vpn, &vpn::script_if_up> (this); |
409 |
if (!run_script (cb, true)) |
410 |
{ |
411 |
slog (L_ERR, _("if-up command execution failed.")); |
412 |
return -1; |
413 |
} |
414 |
|
415 |
tap_ev_watcher.start (tap->fd, EV_READ); |
416 |
|
417 |
return 0; |
418 |
} |
419 |
|
420 |
bool |
421 |
vpn::drop_privileges () |
422 |
{ |
423 |
if (::conf.change_root) |
424 |
{ |
425 |
if (!strcmp (::conf.change_root, "/")) |
426 |
{ |
427 |
char dir [L_tmpnam]; |
428 |
if (!tmpnam (dir)) |
429 |
{ |
430 |
slog (L_CRIT, _("unable to create anonymous root path.")); |
431 |
return false; |
432 |
} |
433 |
|
434 |
if (mkdir (dir, 0700)) |
435 |
{ |
436 |
slog (L_CRIT, _("unable to create anonymous root directory.")); |
437 |
return false; |
438 |
} |
439 |
|
440 |
if (chdir (dir)) |
441 |
{ |
442 |
slog (L_CRIT, _("unable to change to anonymous root directory.")); |
443 |
return false; |
444 |
} |
445 |
|
446 |
if (rmdir (dir)) |
447 |
slog (L_ERR, _("unable to remove anonymous root directory, continuing.")); |
448 |
} |
449 |
else |
450 |
{ |
451 |
if (chdir (::conf.change_root)) |
452 |
{ |
453 |
slog (L_CRIT, _("%s: unable to change to specified root directory."), ::conf.change_root); |
454 |
return false; |
455 |
} |
456 |
} |
457 |
|
458 |
if (chroot (".")) |
459 |
{ |
460 |
slog (L_CRIT, _("unable to set new root directory.")); |
461 |
return false; |
462 |
} |
463 |
|
464 |
if (chdir ("/")) |
465 |
{ |
466 |
slog (L_CRIT, _("unable to set cwd to new root directory.")); |
467 |
return false; |
468 |
} |
469 |
} |
470 |
|
471 |
if (::conf.change_gid) |
472 |
if (setgid (::conf.change_gid)) |
473 |
{ |
474 |
slog (L_CRIT, _("unable to change group id to %d."), ::conf.change_gid); |
475 |
return false; |
476 |
} |
477 |
|
478 |
if (::conf.change_uid) |
479 |
if (setuid (::conf.change_uid)) |
480 |
{ |
481 |
slog (L_CRIT, _("unable to change user id to %d."), ::conf.change_uid); |
482 |
return false; |
483 |
} |
484 |
|
485 |
return true; |
486 |
} |
487 |
|
488 |
bool |
489 |
vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
490 |
{ |
491 |
set_tos (ipv4_fd, ipv4_tos, tos); |
492 |
xsendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
493 |
|
494 |
return true; |
495 |
} |
496 |
|
497 |
static u16 |
498 |
ipv4_checksum (u16 *data, unsigned int len) |
499 |
{ |
500 |
// use 32 bit accumulator and fold back carry bits at the end |
501 |
u32 sum = 0; |
502 |
|
503 |
while (len > 1) |
504 |
{ |
505 |
sum += *data++; |
506 |
len -= 2; |
507 |
} |
508 |
|
509 |
// odd byte left? |
510 |
if (len) |
511 |
sum += *(u8 *)data; |
512 |
|
513 |
// add back carry bits |
514 |
sum = (sum >> 16) + (sum & 0xffff); // lo += hi |
515 |
sum += (sum >> 16); // carry |
516 |
|
517 |
return ~sum; |
518 |
} |
519 |
|
520 |
#if ENABLE_ICMP |
521 |
bool |
522 |
vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
523 |
{ |
524 |
pkt->unshift_hdr (4); |
525 |
|
526 |
icmp_header *hdr = (icmp_header *)&((*pkt)[0]); |
527 |
hdr->type = ::conf.icmp_type; |
528 |
hdr->code = 255; |
529 |
hdr->checksum = 0; |
530 |
hdr->checksum = ipv4_checksum ((u16 *)hdr, pkt->len); |
531 |
|
532 |
set_tos (icmpv4_fd, icmpv4_tos, tos); |
533 |
xsendto (icmpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
534 |
|
535 |
return true; |
536 |
} |
537 |
#endif |
538 |
|
539 |
bool |
540 |
vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
541 |
{ |
542 |
set_tos (udpv4_fd, udpv4_tos, tos); |
543 |
xsendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
544 |
|
545 |
return true; |
546 |
} |
547 |
|
548 |
void |
549 |
vpn::inject_data_packet (tap_packet *pkt, int dst) |
550 |
{ |
551 |
if (dst) |
552 |
{ |
553 |
// unicast |
554 |
if (dst != THISNODE->id) |
555 |
conns[dst - 1]->inject_data_packet (pkt); |
556 |
} |
557 |
else |
558 |
{ |
559 |
// broadcast, this is ugly, but due to the security policy |
560 |
// we have to connect to all hosts... |
561 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
562 |
if ((*c)->conf != THISNODE) |
563 |
(*c)->inject_data_packet (pkt); |
564 |
} |
565 |
} |
566 |
|
567 |
void |
568 |
vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
569 |
{ |
570 |
unsigned int src = pkt->src (); |
571 |
unsigned int dst = pkt->dst (); |
572 |
|
573 |
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d."), |
574 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
575 |
|
576 |
if (src == 0 || src > conns.size () |
577 |
|| dst > conns.size () |
578 |
|| pkt->typ () >= vpn_packet::PT_MAX) |
579 |
slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."), |
580 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ()); |
581 |
else |
582 |
{ |
583 |
connection *c = conns[src - 1]; |
584 |
|
585 |
if (dst == 0) |
586 |
slog (L_WARN, _("%s(%s): received broadcast (protocol violation)."), |
587 |
c->conf->nodename, (const char *)rsi); |
588 |
else if (dst != THISNODE->id) |
589 |
{ |
590 |
if (THISNODE->routerprio) |
591 |
// the tos setting gets lost here. who cares. |
592 |
conns[dst - 1]->inject_vpn_packet (pkt); |
593 |
else |
594 |
slog (L_WARN, |
595 |
_("%s(%s): request to forward packet to %s, but we are no router (config mismatch?)."), |
596 |
c->conf->nodename, (const char *)rsi, |
597 |
conns[dst - 1]->conf->nodename); |
598 |
} |
599 |
else |
600 |
c->recv_vpn_packet (pkt, rsi); |
601 |
} |
602 |
} |
603 |
|
604 |
bool |
605 |
vpn::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
606 |
{ |
607 |
switch (si.prot) |
608 |
{ |
609 |
case PROT_IPv4: |
610 |
return send_ipv4_packet (pkt, si, tos); |
611 |
|
612 |
case PROT_UDPv4: |
613 |
return send_udpv4_packet (pkt, si, tos); |
614 |
|
615 |
#if ENABLE_TCP |
616 |
case PROT_TCPv4: |
617 |
return send_tcpv4_packet (pkt, si, tos); |
618 |
#endif |
619 |
#if ENABLE_ICMP |
620 |
case PROT_ICMPv4: |
621 |
return send_icmpv4_packet (pkt, si, tos); |
622 |
#endif |
623 |
#if ENABLE_DNS |
624 |
case PROT_DNSv4: |
625 |
return send_dnsv4_packet (pkt, si, tos); |
626 |
#endif |
627 |
default: |
628 |
slog (L_CRIT, _("%s: FATAL: trying to send packet with unsupported protocol."), (const char *)si); |
629 |
} |
630 |
|
631 |
return false; |
632 |
} |
633 |
|
634 |
inline void |
635 |
vpn::ipv4_ev (ev::io &w, int revents) |
636 |
{ |
637 |
if (revents & EV_READ) |
638 |
{ |
639 |
vpn_packet *pkt = new vpn_packet; |
640 |
struct sockaddr_in sa; |
641 |
socklen_t sa_len = sizeof (sa); |
642 |
int len; |
643 |
|
644 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
645 |
|
646 |
sockinfo si(sa, PROT_IPv4); |
647 |
|
648 |
if (len > 0) |
649 |
{ |
650 |
pkt->len = len; |
651 |
|
652 |
// raw sockets deliver the ipv4 header, but don't expect it on sends |
653 |
pkt->skip_hdr (pkt->ipv4_hdr_len ()); |
654 |
|
655 |
recv_vpn_packet (pkt, si); |
656 |
} |
657 |
else |
658 |
{ |
659 |
// probably ECONNRESET or somesuch |
660 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
661 |
} |
662 |
|
663 |
delete pkt; |
664 |
} |
665 |
else |
666 |
{ |
667 |
slog (L_ERR, |
668 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
669 |
revents); |
670 |
exit (EXIT_FAILURE); |
671 |
} |
672 |
} |
673 |
|
674 |
#if ENABLE_ICMP |
675 |
inline void |
676 |
vpn::icmpv4_ev (ev::io &w, int revents) |
677 |
{ |
678 |
if (revents & EV_READ) |
679 |
{ |
680 |
vpn_packet *pkt = new vpn_packet; |
681 |
struct sockaddr_in sa; |
682 |
socklen_t sa_len = sizeof (sa); |
683 |
int len; |
684 |
|
685 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
686 |
|
687 |
sockinfo si(sa, PROT_ICMPv4); |
688 |
|
689 |
if (len > 0) |
690 |
{ |
691 |
pkt->len = len; |
692 |
|
693 |
icmp_header *hdr = (icmp_header *)&((*pkt)[IP_OVERHEAD]); |
694 |
|
695 |
if (hdr->type == ::conf.icmp_type |
696 |
&& hdr->code == 255) |
697 |
{ |
698 |
// raw sockets deliver the ipv4, but don't expect it on sends |
699 |
// this is slow, but... |
700 |
pkt->skip_hdr (pkt->ipv4_hdr_len () + (ICMP_OVERHEAD - IP_OVERHEAD)); |
701 |
|
702 |
recv_vpn_packet (pkt, si); |
703 |
} |
704 |
} |
705 |
else |
706 |
{ |
707 |
// probably ECONNRESET or somesuch |
708 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
709 |
} |
710 |
|
711 |
delete pkt; |
712 |
} |
713 |
else |
714 |
{ |
715 |
slog (L_ERR, |
716 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
717 |
revents); |
718 |
exit (EXIT_FAILURE); |
719 |
} |
720 |
} |
721 |
#endif |
722 |
|
723 |
inline void |
724 |
vpn::udpv4_ev (ev::io &w, int revents) |
725 |
{ |
726 |
if (revents & EV_READ) |
727 |
{ |
728 |
vpn_packet *pkt = new vpn_packet; |
729 |
struct sockaddr_in sa; |
730 |
socklen_t sa_len = sizeof (sa); |
731 |
int len; |
732 |
|
733 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
734 |
|
735 |
sockinfo si(sa, PROT_UDPv4); |
736 |
|
737 |
if (len > 0) |
738 |
{ |
739 |
pkt->len = len; |
740 |
|
741 |
recv_vpn_packet (pkt, si); |
742 |
} |
743 |
else |
744 |
{ |
745 |
// probably ECONNRESET or somesuch |
746 |
slog (L_DEBUG, _("%s: fd %d, %s."), (const char *)si, w.fd, strerror (errno)); |
747 |
} |
748 |
|
749 |
delete pkt; |
750 |
} |
751 |
else |
752 |
{ |
753 |
slog (L_ERR, |
754 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
755 |
revents); |
756 |
exit (EXIT_FAILURE); |
757 |
} |
758 |
} |
759 |
|
760 |
inline void |
761 |
vpn::tap_ev (ev::io &w, int revents) |
762 |
{ |
763 |
if (revents & EV_READ) |
764 |
{ |
765 |
/* process data */ |
766 |
tap_packet *pkt; |
767 |
|
768 |
pkt = tap->recv (); |
769 |
|
770 |
if (!pkt) |
771 |
return; |
772 |
|
773 |
if (pkt->len > 14) |
774 |
{ |
775 |
int dst = mac2id (pkt->dst); |
776 |
int src = mac2id (pkt->src); |
777 |
|
778 |
if (src != THISNODE->id) |
779 |
{ |
780 |
slog (L_ERR, _("FATAL: tap packet not originating on current node received (if-up script not working properly?), exiting.")); |
781 |
exit (EXIT_FAILURE); |
782 |
} |
783 |
|
784 |
if (dst == THISNODE->id) |
785 |
{ |
786 |
slog (L_ERR, _("FATAL: tap packet destined for current node received, exiting.")); |
787 |
exit (EXIT_FAILURE); |
788 |
} |
789 |
|
790 |
if (dst > conns.size ()) |
791 |
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
792 |
else |
793 |
inject_data_packet (pkt, dst); |
794 |
} |
795 |
|
796 |
delete pkt; |
797 |
} |
798 |
else |
799 |
abort (); |
800 |
} |
801 |
|
802 |
inline void |
803 |
vpn::event_cb (ev::timer &w, int) |
804 |
{ |
805 |
if (events) |
806 |
{ |
807 |
if (events & EVENT_SHUTDOWN) |
808 |
{ |
809 |
slog (L_INFO, _("preparing shutdown...")); |
810 |
|
811 |
shutdown_all (); |
812 |
remove_pid (conf.pidfilename); |
813 |
slog (L_INFO, _("exiting.")); |
814 |
exit (EXIT_SUCCESS); |
815 |
} |
816 |
|
817 |
if (events & EVENT_RECONNECT) |
818 |
{ |
819 |
slog (L_INFO, _("forced reconnect.")); |
820 |
|
821 |
reconnect_all (); |
822 |
} |
823 |
|
824 |
events = 0; |
825 |
} |
826 |
} |
827 |
|
828 |
void |
829 |
vpn::shutdown_all () |
830 |
{ |
831 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
832 |
(*c)->shutdown (); |
833 |
} |
834 |
|
835 |
void |
836 |
vpn::reconnect_all () |
837 |
{ |
838 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
839 |
delete *c; |
840 |
|
841 |
conns.clear (); |
842 |
|
843 |
connection_init (); |
844 |
|
845 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); i != conf.nodes.end (); ++i) |
846 |
conns.push_back (new connection (this, *i)); |
847 |
|
848 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
849 |
(*c)->establish_connection (); |
850 |
} |
851 |
|
852 |
bool |
853 |
vpn::can_direct (conf_node *src, conf_node *dst) const |
854 |
{ |
855 |
return src != dst |
856 |
&& src->may_direct (dst) |
857 |
&& dst->may_direct (src) |
858 |
&& (((src->protocols & dst->protocols) && src->connectmode == conf_node::C_ALWAYS) |
859 |
|| (src->protocols & dst->connectable_protocols ())); |
860 |
} |
861 |
|
862 |
// only works for indirect and routed connections: find a router |
863 |
// from THISNODE to dst |
864 |
connection * |
865 |
vpn::find_router_for (const connection *dst) |
866 |
{ |
867 |
connection *router = 0; |
868 |
|
869 |
// first try to find a router with a direct connection, route there |
870 |
// regardless of any other considerations. |
871 |
{ |
872 |
u32 prio = 1; |
873 |
|
874 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
875 |
{ |
876 |
connection *c = *i; |
877 |
|
878 |
if (c->conf->routerprio > prio |
879 |
&& c->conf != THISNODE |
880 |
&& can_direct (c->conf, dst->conf) |
881 |
&& c->ictx && c->octx) |
882 |
{ |
883 |
prio = c->conf->routerprio; |
884 |
router = c; |
885 |
} |
886 |
} |
887 |
} |
888 |
|
889 |
if (router) |
890 |
return router; |
891 |
|
892 |
// second try find the router with the highest priority, higher than ours |
893 |
{ |
894 |
u32 prio = THISNODE->routerprio ? THISNODE->routerprio : 1; |
895 |
|
896 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
897 |
{ |
898 |
connection *c = *i; |
899 |
|
900 |
if (c->conf->routerprio > prio |
901 |
&& c != dst |
902 |
&& c->conf != THISNODE |
903 |
&& c->ictx && c->octx) |
904 |
{ |
905 |
prio = c->conf->routerprio; |
906 |
router = c; |
907 |
} |
908 |
} |
909 |
} |
910 |
|
911 |
return router; |
912 |
} |
913 |
|
914 |
void |
915 |
vpn::connection_established (connection *c) |
916 |
{ |
917 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
918 |
{ |
919 |
connection *o = *i; |
920 |
|
921 |
if (o->si.valid () |
922 |
&& c->si != o->si |
923 |
&& c == find_router_for (o) |
924 |
&& !can_direct (THISNODE, o->conf)) |
925 |
{ |
926 |
slog (L_DEBUG, _("%s: can now route packets via %s, re-keying connection."), |
927 |
o->conf->nodename, c->conf->nodename); |
928 |
o->rekey (); |
929 |
} |
930 |
} |
931 |
} |
932 |
|
933 |
void |
934 |
vpn::send_connect_request (connection *c) |
935 |
{ |
936 |
connection *r = find_router_for (c); |
937 |
|
938 |
if (r) |
939 |
{ |
940 |
slog (L_TRACE, _("%s: no address known, sending mediated connection request via %s."), |
941 |
c->conf->nodename, r->conf->nodename); |
942 |
r->send_connect_request (c->conf->id); |
943 |
} |
944 |
else |
945 |
slog (L_DEBUG, _("%s: no way to connect and no router found: unable to connect at this time."), |
946 |
c->conf->nodename); |
947 |
} |
948 |
|
949 |
void |
950 |
connection::dump_status () |
951 |
{ |
952 |
slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id); |
953 |
slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"), |
954 |
connectmode, conf->connectmode, (const char *)si, (int)prot_minor); |
955 |
slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"), |
956 |
(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt); |
957 |
} |
958 |
|
959 |
void |
960 |
vpn::dump_status () |
961 |
{ |
962 |
slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)ev_now ()); |
963 |
|
964 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
965 |
(*c)->dump_status (); |
966 |
|
967 |
slog (L_NOTICE, _("END status dump")); |
968 |
} |
969 |
|
970 |
vpn::vpn (void) |
971 |
{ |
972 |
event .set<vpn, &vpn::event_cb > (this); |
973 |
udpv4_ev_watcher .set<vpn, &vpn::udpv4_ev > (this); |
974 |
ipv4_ev_watcher .set<vpn, &vpn::ipv4_ev > (this); |
975 |
#if ENABLE_TCP |
976 |
tcpv4_ev_watcher .set<vpn, &vpn::tcpv4_ev > (this); |
977 |
#endif |
978 |
#if ENABLE_ICMP |
979 |
icmpv4_ev_watcher.set<vpn, &vpn::icmpv4_ev> (this); |
980 |
#endif |
981 |
#if ENABLE_DNS |
982 |
dnsv4_ev_watcher .set<vpn, &vpn::dnsv4_ev > (this); |
983 |
#endif |
984 |
tap_ev_watcher .set<vpn, &vpn::tap_ev > (this); |
985 |
} |
986 |
|
987 |
vpn::~vpn () |
988 |
{ |
989 |
} |
990 |
|