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/* |
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vpn.C -- handle the protocol, encryption, handshaking etc. |
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Copyright (C) 2003-2008 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 <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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vpn network; // THE vpn (bad design...) |
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|
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///////////////////////////////////////////////////////////////////////////// |
60 |
|
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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 % EVP_CIPHER_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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char *filename; |
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asprintf (&filename, |
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"%s/%s", |
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confbase, |
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::conf.script_if_up ? ::conf.script_if_up : "if-up"); |
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|
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return filename; |
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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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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 = socket (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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fcntl (ipv4_fd, F_SETFL, O_NONBLOCK); |
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fcntl (ipv4_fd, F_SETFD, FD_CLOEXEC); |
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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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exit (EXIT_FAILURE); |
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} |
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|
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ipv4_ev_watcher.start (ipv4_fd, EV_READ); |
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} |
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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 = socket (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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fcntl (udpv4_fd, F_SETFL, O_NONBLOCK); |
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fcntl (udpv4_fd, F_SETFD, FD_CLOEXEC); |
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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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exit (EXIT_FAILURE); |
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} |
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|
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udpv4_ev_watcher.start (udpv4_fd, EV_READ); |
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} |
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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 = socket (PF_INET, SOCK_RAW, IPPROTO_ICMP); |
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|
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if (icmpv4_fd < 0) |
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return -1; |
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|
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fcntl (icmpv4_fd, F_SETFL, O_NONBLOCK); |
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fcntl (icmpv4_fd, F_SETFD, FD_CLOEXEC); |
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|
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#ifdef ICMP_FILTER |
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{ |
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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 |
225 |
|
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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 (icmpv4_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_ICMPv4); |
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|
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if (bind (icmpv4_fd, si.sav4 (), si.salenv4 ())) |
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{ |
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slog (L_ERR, _("can't bind icmpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
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exit (EXIT_FAILURE); |
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} |
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|
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icmpv4_ev_watcher.start (icmpv4_fd, EV_READ); |
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} |
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#endif |
247 |
|
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tcpv4_fd = -1; |
249 |
|
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#if ENABLE_TCP |
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if (THISNODE->protocols & PROT_TCPv4 && THISNODE->tcp_port) |
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{ |
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tcpv4_fd = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP); |
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|
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if (tcpv4_fd < 0) |
256 |
return -1; |
257 |
|
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fcntl (tcpv4_fd, F_SETFL, O_NONBLOCK); |
259 |
fcntl (tcpv4_fd, F_SETFD, FD_CLOEXEC); |
260 |
|
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// standard daemon practise... |
262 |
{ |
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int oval = 1; |
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setsockopt (tcpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
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} |
266 |
|
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sockinfo si (THISNODE, PROT_TCPv4); |
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|
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if (bind (tcpv4_fd, si.sav4 (), si.salenv4 ())) |
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{ |
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slog (L_ERR, _("can't bind tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
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exit (EXIT_FAILURE); |
273 |
} |
274 |
|
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if (listen (tcpv4_fd, 5)) |
276 |
{ |
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slog (L_ERR, _("can't listen tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
278 |
exit (EXIT_FAILURE); |
279 |
} |
280 |
|
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tcpv4_ev_watcher.start (tcpv4_fd, EV_READ); |
282 |
} |
283 |
#endif |
284 |
|
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dnsv4_tos = -1; |
286 |
dnsv4_fd = -1; |
287 |
|
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#if ENABLE_DNS |
289 |
if (THISNODE->protocols & PROT_DNSv4) |
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{ |
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dns_forwarder.set (::conf.dns_forw_host, ::conf.dns_forw_port, PROT_DNSv4); |
292 |
|
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dnsv4_fd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
294 |
|
295 |
if (dnsv4_fd < 0) |
296 |
return -1; |
297 |
|
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fcntl (dnsv4_fd, F_SETFL, O_NONBLOCK); |
299 |
fcntl (dnsv4_fd, F_SETFD, FD_CLOEXEC); |
300 |
|
301 |
# if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
302 |
// this I really consider a linux bug. I am neither connected |
303 |
// nor do I fragment myself. Linux still sets DF and doesn't |
304 |
// fragment for me sometimes. |
305 |
{ |
306 |
int oval = IP_PMTUDISC_DONT; |
307 |
setsockopt (dnsv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
308 |
} |
309 |
# endif |
310 |
|
311 |
// standard daemon practise... |
312 |
{ |
313 |
int oval = 1; |
314 |
setsockopt (dnsv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
315 |
} |
316 |
|
317 |
sockinfo si (THISNODE->dns_hostname, |
318 |
THISNODE->dns_hostname ? THISNODE->dns_port : 0, |
319 |
PROT_DNSv4); |
320 |
|
321 |
if (bind (dnsv4_fd, si.sav4 (), si.salenv4 ())) |
322 |
{ |
323 |
slog (L_ERR, _("can't bind dnsv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
324 |
exit (EXIT_FAILURE); |
325 |
} |
326 |
|
327 |
dnsv4_ev_watcher.start (dnsv4_fd, EV_READ); |
328 |
} |
329 |
#endif |
330 |
|
331 |
///////////////////////////////////////////////////////////////////////////// |
332 |
|
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reconnect_all (); |
334 |
|
335 |
///////////////////////////////////////////////////////////////////////////// |
336 |
|
337 |
tap = new tap_device (); |
338 |
if (!tap) //D this, of course, never catches |
339 |
{ |
340 |
slog (L_ERR, _("cannot create network interface '%s', exiting."), conf.ifname); |
341 |
exit (EXIT_FAILURE); |
342 |
} |
343 |
|
344 |
fcntl (tap->fd, F_SETFD, FD_CLOEXEC); |
345 |
|
346 |
run_script_cb cb; |
347 |
cb.set<vpn, &vpn::script_if_init> (this); |
348 |
|
349 |
if (tap->if_up () && |
350 |
!run_script (cb, true)) |
351 |
{ |
352 |
slog (L_ERR, _("interface initialization command '%s' failed, exiting."), |
353 |
tap->if_up ()); |
354 |
exit (EXIT_FAILURE); |
355 |
} |
356 |
|
357 |
cb.set<vpn, &vpn::script_if_up> (this); |
358 |
if (!run_script (cb, true)) |
359 |
{ |
360 |
slog (L_ERR, _("if-up command execution failed, exiting.")); |
361 |
exit (EXIT_FAILURE); |
362 |
} |
363 |
|
364 |
tap_ev_watcher.start (tap->fd, EV_READ); |
365 |
|
366 |
return 0; |
367 |
} |
368 |
|
369 |
bool |
370 |
vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
371 |
{ |
372 |
set_tos (ipv4_fd, ipv4_tos, tos); |
373 |
sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
374 |
|
375 |
return true; |
376 |
} |
377 |
|
378 |
static u16 |
379 |
ipv4_checksum (u16 *data, unsigned int len) |
380 |
{ |
381 |
// use 32 bit accumulator and fold back carry bits at the end |
382 |
u32 sum = 0; |
383 |
|
384 |
while (len > 1) |
385 |
{ |
386 |
sum += *data++; |
387 |
len -= 2; |
388 |
} |
389 |
|
390 |
// odd byte left? |
391 |
if (len) |
392 |
sum += *(u8 *)data; |
393 |
|
394 |
// add back carry bits |
395 |
sum = (sum >> 16) + (sum & 0xffff); // lo += hi |
396 |
sum += (sum >> 16); // carry |
397 |
|
398 |
return ~sum; |
399 |
} |
400 |
|
401 |
#if ENABLE_ICMP |
402 |
bool |
403 |
vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
404 |
{ |
405 |
pkt->unshift_hdr (4); |
406 |
|
407 |
icmp_header *hdr = (icmp_header *)&((*pkt)[0]); |
408 |
hdr->type = ::conf.icmp_type; |
409 |
hdr->code = 255; |
410 |
hdr->checksum = 0; |
411 |
hdr->checksum = ipv4_checksum ((u16 *)hdr, pkt->len); |
412 |
|
413 |
set_tos (icmpv4_fd, icmpv4_tos, tos); |
414 |
sendto (icmpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
415 |
|
416 |
return true; |
417 |
} |
418 |
#endif |
419 |
|
420 |
bool |
421 |
vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
422 |
{ |
423 |
set_tos (udpv4_fd, udpv4_tos, tos); |
424 |
sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
425 |
|
426 |
return true; |
427 |
} |
428 |
|
429 |
void |
430 |
vpn::inject_data_packet (tap_packet *pkt, int dst) |
431 |
{ |
432 |
if (dst) |
433 |
{ |
434 |
// unicast |
435 |
if (dst != THISNODE->id) |
436 |
conns[dst - 1]->inject_data_packet (pkt); |
437 |
} |
438 |
else |
439 |
{ |
440 |
// broadcast, this is ugly, but due to the security policy |
441 |
// we have to connect to all hosts... |
442 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
443 |
if ((*c)->conf != THISNODE) |
444 |
(*c)->inject_data_packet (pkt); |
445 |
} |
446 |
} |
447 |
|
448 |
void |
449 |
vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
450 |
{ |
451 |
unsigned int src = pkt->src (); |
452 |
unsigned int dst = pkt->dst (); |
453 |
|
454 |
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d."), |
455 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
456 |
|
457 |
if (src == 0 || src > conns.size () |
458 |
|| dst > conns.size () |
459 |
|| pkt->typ () >= vpn_packet::PT_MAX) |
460 |
slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."), |
461 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ()); |
462 |
else if (dst > conns.size ()) |
463 |
slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."), |
464 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ()); |
465 |
else |
466 |
{ |
467 |
connection *c = conns[src - 1]; |
468 |
|
469 |
if (dst == 0) |
470 |
slog (L_WARN, _("%s(%s): received broadcast (protocol violation)."), |
471 |
c->conf->nodename, (const char *)rsi); |
472 |
else if (dst != THISNODE->id) |
473 |
{ |
474 |
if (THISNODE->routerprio) |
475 |
// the tos setting gets lost here. who cares. |
476 |
conns[dst - 1]->inject_vpn_packet (pkt); |
477 |
else |
478 |
slog (L_WARN, |
479 |
_("%s(%s): request to forward packet to %s, but we are no router (config mismatch?)."), |
480 |
c->conf->nodename, (const char *)rsi, |
481 |
conns[dst - 1]->conf->nodename); |
482 |
} |
483 |
else |
484 |
c->recv_vpn_packet (pkt, rsi); |
485 |
} |
486 |
} |
487 |
|
488 |
bool |
489 |
vpn::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
490 |
{ |
491 |
switch (si.prot) |
492 |
{ |
493 |
case PROT_IPv4: |
494 |
return send_ipv4_packet (pkt, si, tos); |
495 |
|
496 |
case PROT_UDPv4: |
497 |
return send_udpv4_packet (pkt, si, tos); |
498 |
|
499 |
#if ENABLE_TCP |
500 |
case PROT_TCPv4: |
501 |
return send_tcpv4_packet (pkt, si, tos); |
502 |
#endif |
503 |
#if ENABLE_ICMP |
504 |
case PROT_ICMPv4: |
505 |
return send_icmpv4_packet (pkt, si, tos); |
506 |
#endif |
507 |
#if ENABLE_DNS |
508 |
case PROT_DNSv4: |
509 |
return send_dnsv4_packet (pkt, si, tos); |
510 |
#endif |
511 |
default: |
512 |
slog (L_CRIT, _("%s: FATAL: trying to send packet with unsupported protocol."), (const char *)si); |
513 |
} |
514 |
|
515 |
return false; |
516 |
} |
517 |
|
518 |
inline void |
519 |
vpn::ipv4_ev (ev::io &w, int revents) |
520 |
{ |
521 |
if (revents & EV_READ) |
522 |
{ |
523 |
vpn_packet *pkt = new vpn_packet; |
524 |
struct sockaddr_in sa; |
525 |
socklen_t sa_len = sizeof (sa); |
526 |
int len; |
527 |
|
528 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
529 |
|
530 |
sockinfo si(sa, PROT_IPv4); |
531 |
|
532 |
if (len > 0) |
533 |
{ |
534 |
pkt->len = len; |
535 |
|
536 |
// raw sockets deliver the ipv4 header, but don't expect it on sends |
537 |
pkt->skip_hdr (IP_OVERHEAD); |
538 |
|
539 |
recv_vpn_packet (pkt, si); |
540 |
} |
541 |
else |
542 |
{ |
543 |
// probably ECONNRESET or somesuch |
544 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
545 |
} |
546 |
|
547 |
delete pkt; |
548 |
} |
549 |
else |
550 |
{ |
551 |
slog (L_ERR, |
552 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
553 |
revents); |
554 |
exit (EXIT_FAILURE); |
555 |
} |
556 |
} |
557 |
|
558 |
#if ENABLE_ICMP |
559 |
inline void |
560 |
vpn::icmpv4_ev (ev::io &w, int revents) |
561 |
{ |
562 |
if (revents & EV_READ) |
563 |
{ |
564 |
vpn_packet *pkt = new vpn_packet; |
565 |
struct sockaddr_in sa; |
566 |
socklen_t sa_len = sizeof (sa); |
567 |
int len; |
568 |
|
569 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
570 |
|
571 |
sockinfo si(sa, PROT_ICMPv4); |
572 |
|
573 |
if (len > 0) |
574 |
{ |
575 |
pkt->len = len; |
576 |
|
577 |
icmp_header *hdr = (icmp_header *)&((*pkt)[IP_OVERHEAD]); |
578 |
|
579 |
if (hdr->type == ::conf.icmp_type |
580 |
&& hdr->code == 255) |
581 |
{ |
582 |
// raw sockets deliver the ipv4, but don't expect it on sends |
583 |
// this is slow, but... |
584 |
pkt->skip_hdr (ICMP_OVERHEAD); |
585 |
|
586 |
recv_vpn_packet (pkt, si); |
587 |
} |
588 |
} |
589 |
else |
590 |
{ |
591 |
// probably ECONNRESET or somesuch |
592 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
593 |
} |
594 |
|
595 |
delete pkt; |
596 |
} |
597 |
else |
598 |
{ |
599 |
slog (L_ERR, |
600 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
601 |
revents); |
602 |
exit (EXIT_FAILURE); |
603 |
} |
604 |
} |
605 |
#endif |
606 |
|
607 |
inline void |
608 |
vpn::udpv4_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_UDPv4); |
620 |
|
621 |
if (len > 0) |
622 |
{ |
623 |
pkt->len = len; |
624 |
|
625 |
recv_vpn_packet (pkt, si); |
626 |
} |
627 |
else |
628 |
{ |
629 |
// probably ECONNRESET or somesuch |
630 |
slog (L_DEBUG, _("%s: fd %d, %s."), (const char *)si, w.fd, strerror (errno)); |
631 |
} |
632 |
|
633 |
delete pkt; |
634 |
} |
635 |
else |
636 |
{ |
637 |
slog (L_ERR, |
638 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
639 |
revents); |
640 |
exit (EXIT_FAILURE); |
641 |
} |
642 |
} |
643 |
|
644 |
inline void |
645 |
vpn::tap_ev (ev::io &w, int revents) |
646 |
{ |
647 |
if (revents & EV_READ) |
648 |
{ |
649 |
/* process data */ |
650 |
tap_packet *pkt; |
651 |
|
652 |
pkt = tap->recv (); |
653 |
|
654 |
if (!pkt) |
655 |
return; |
656 |
|
657 |
if (pkt->len > 14) |
658 |
{ |
659 |
int dst = mac2id (pkt->dst); |
660 |
int src = mac2id (pkt->src); |
661 |
|
662 |
if (src != THISNODE->id) |
663 |
{ |
664 |
slog (L_ERR, _("FATAL: tap packet not originating on current node received (if-up script not working properly?), exiting.")); |
665 |
exit (EXIT_FAILURE); |
666 |
} |
667 |
|
668 |
if (dst == THISNODE->id) |
669 |
{ |
670 |
slog (L_ERR, _("FATAL: tap packet destined for current node received, exiting.")); |
671 |
exit (EXIT_FAILURE); |
672 |
} |
673 |
|
674 |
if (dst > conns.size ()) |
675 |
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
676 |
else |
677 |
inject_data_packet (pkt, dst); |
678 |
} |
679 |
|
680 |
delete pkt; |
681 |
} |
682 |
else |
683 |
abort (); |
684 |
} |
685 |
|
686 |
inline void |
687 |
vpn::event_cb (ev::timer &w, int) |
688 |
{ |
689 |
if (events) |
690 |
{ |
691 |
if (events & EVENT_SHUTDOWN) |
692 |
{ |
693 |
slog (L_INFO, _("preparing shutdown...")); |
694 |
|
695 |
shutdown_all (); |
696 |
remove_pid (conf.pidfilename); |
697 |
slog (L_INFO, _("exiting.")); |
698 |
exit (EXIT_SUCCESS); |
699 |
} |
700 |
|
701 |
if (events & EVENT_RECONNECT) |
702 |
{ |
703 |
slog (L_INFO, _("forced reconnect.")); |
704 |
|
705 |
reconnect_all (); |
706 |
} |
707 |
|
708 |
events = 0; |
709 |
} |
710 |
} |
711 |
|
712 |
void |
713 |
vpn::shutdown_all () |
714 |
{ |
715 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
716 |
(*c)->shutdown (); |
717 |
} |
718 |
|
719 |
void |
720 |
vpn::reconnect_all () |
721 |
{ |
722 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
723 |
delete *c; |
724 |
|
725 |
conns.clear (); |
726 |
|
727 |
connection_init (); |
728 |
|
729 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); |
730 |
i != conf.nodes.end (); ++i) |
731 |
{ |
732 |
connection *conn = new connection (this, *i); |
733 |
conns.push_back (conn); |
734 |
conn->establish_connection (); |
735 |
} |
736 |
} |
737 |
|
738 |
bool vpn::can_direct (conf_node *src, conf_node *dst) const |
739 |
{ |
740 |
return src != dst |
741 |
&& src->may_direct (dst) |
742 |
&& dst->may_direct (src) |
743 |
&& (((src->protocols & dst->protocols) && src->connectmode == conf_node::C_ALWAYS) |
744 |
|| (src->protocols & dst->connectable_protocols ())); |
745 |
} |
746 |
|
747 |
// only works for indirect and routed connections: find a router |
748 |
// from THISNODE to dst |
749 |
connection *vpn::find_router_for (const connection *dst) |
750 |
{ |
751 |
connection *router = 0; |
752 |
|
753 |
// first try to find a router with a direct connection |
754 |
{ |
755 |
u32 prio = 1; |
756 |
|
757 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
758 |
{ |
759 |
connection *c = *i; |
760 |
|
761 |
if (c->conf->routerprio > prio |
762 |
&& c->conf != THISNODE |
763 |
&& c != dst |
764 |
&& can_direct (c->conf, dst->conf)) |
765 |
{ |
766 |
if (c->ictx && c->octx) |
767 |
{ |
768 |
prio = c->conf->routerprio; |
769 |
router = c; |
770 |
} |
771 |
else |
772 |
c->establish_connection (); |
773 |
} |
774 |
} |
775 |
} |
776 |
|
777 |
if (router) |
778 |
return router; |
779 |
|
780 |
// second try find the router with the highest priority higher than ours |
781 |
{ |
782 |
u32 prio = 1; |
783 |
|
784 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
785 |
{ |
786 |
connection *c = *i; |
787 |
|
788 |
if (c->conf->routerprio > prio |
789 |
&& c->conf->routerprio > THISNODE->routerprio |
790 |
&& c != dst |
791 |
&& c->conf != THISNODE) |
792 |
{ |
793 |
if (c->ictx && c->octx) |
794 |
{ |
795 |
prio = c->conf->routerprio; |
796 |
router = c; |
797 |
} |
798 |
else |
799 |
c->establish_connection (); |
800 |
} |
801 |
} |
802 |
} |
803 |
return router; |
804 |
} |
805 |
|
806 |
void vpn::connection_established (connection *c) |
807 |
{ |
808 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
809 |
{ |
810 |
connection *o = *i; |
811 |
|
812 |
if (!o->is_direct |
813 |
&& o->si.valid () |
814 |
&& c->si != o->si |
815 |
&& c == find_router_for (o)) |
816 |
{ |
817 |
slog (L_DEBUG, _("%s: can now route packets via %s, re-keying connection."), |
818 |
o->conf->nodename, c->conf->nodename); |
819 |
o->rekey (); |
820 |
} |
821 |
} |
822 |
} |
823 |
|
824 |
void vpn::send_connect_request (int id) |
825 |
{ |
826 |
connection *c = find_router_for (conns[id]); |
827 |
|
828 |
if (c) |
829 |
{ |
830 |
slog (L_TRACE, _("%s: no way to connect, sending mediated connection request via %s."), |
831 |
conns[id]->conf->nodename, c->conf->nodename); |
832 |
c->send_connect_request (id); |
833 |
} |
834 |
else |
835 |
slog (L_DEBUG, _("%s: no way to connect and no router found: unable to connect."), conns[id]->conf->nodename); |
836 |
} |
837 |
|
838 |
void |
839 |
connection::dump_status () |
840 |
{ |
841 |
slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id); |
842 |
slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"), |
843 |
connectmode, conf->connectmode, (const char *)si, (int)prot_minor); |
844 |
slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"), |
845 |
(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt); |
846 |
} |
847 |
|
848 |
void |
849 |
vpn::dump_status () |
850 |
{ |
851 |
slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)ev_now ()); |
852 |
|
853 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
854 |
(*c)->dump_status (); |
855 |
|
856 |
slog (L_NOTICE, _("END status dump")); |
857 |
} |
858 |
|
859 |
vpn::vpn (void) |
860 |
{ |
861 |
event .set<vpn, &vpn::event_cb > (this); |
862 |
udpv4_ev_watcher .set<vpn, &vpn::udpv4_ev > (this); |
863 |
ipv4_ev_watcher .set<vpn, &vpn::ipv4_ev > (this); |
864 |
#if ENABLE_TCP |
865 |
tcpv4_ev_watcher .set<vpn, &vpn::tcpv4_ev > (this); |
866 |
#endif |
867 |
#if ENABLE_ICMP |
868 |
icmpv4_ev_watcher.set<vpn, &vpn::icmpv4_ev> (this); |
869 |
#endif |
870 |
#if ENABLE_DNS |
871 |
dnsv4_ev_watcher .set<vpn, &vpn::dnsv4_ev > (this); |
872 |
#endif |
873 |
tap_ev_watcher .set<vpn, &vpn::tap_ev > (this); |
874 |
} |
875 |
|
876 |
vpn::~vpn () |
877 |
{ |
878 |
} |
879 |
|