[ViewVC] Diff of: cvs/gvpe/src/vpn.C

Comparing gvpe/src/vpn.C (file contents):
Revision 1.1 by pcg, Wed Apr 2 03:25:17 2003 UTC vs.
Revision 1.70 by root, Thu Oct 6 03:03:09 2022 UTC

…		…
1	/*	1	/*
2	vpn.C -- handle the protocol, encryption, handshaking etc.	2	vpn.C -- handle the protocol, encryption, handshaking etc.
		3	Copyright (C) 2003-2008,2010,2011,2013 Marc Lehmann <gvpe@schmorp.de>
3		4
		5	This file is part of GVPE.
		6
4	This program is free software; you can redistribute it and/or modify	7	GVPE is free software; you can redistribute it and/or modify it
5	it under the terms of the GNU General Public License as published by	8	under the terms of the GNU General Public License as published by the
6	the Free Software Foundation; either version 2 of the License, or	9	Free Software Foundation; either version 3 of the License, or (at your
7	(at your option) any later version.	10	option) any later version.
8		11
9	This program is distributed in the hope that it will be useful,	12	This program is distributed in the hope that it will be useful, but
10	but WITHOUT ANY WARRANTY; without even the implied warranty of	13	WITHOUT ANY WARRANTY; without even the implied warranty of
11	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
12	GNU General Public License for more details.	15	Public License for more details.
13		16
14	You should have received a copy of the GNU General Public License	17	You should have received a copy of the GNU General Public License along
15	along with this program; if not, write to the Free Software	18	with this program; if not, see <http://www.gnu.org/licenses/>.
16	Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA	19
		20	Additional permission under GNU GPL version 3 section 7
		21
		22	If you modify this Program, or any covered work, by linking or
		23	combining it with the OpenSSL project's OpenSSL library (or a modified
		24	version of that library), containing parts covered by the terms of the
		25	OpenSSL or SSLeay licenses, the licensors of this Program grant you
		26	additional permission to convey the resulting work. Corresponding
		27	Source for a non-source form of such a combination shall include the
		28	source code for the parts of OpenSSL used as well as that of the
		29	covered work.
17	*/	30	*/
18		31
19	#include "config.h"	32	#include "config.h"
20		33
21	#include <list>	34	#include <list>
22		35
		36	#include <cstdio>
		37	#include <cstring>
23	#include <cstdlib>	38	#include <cstdlib>
24	#include <cstring>
25	#include <cstdio>
26		39
27	#include <sys/types.h>	40	#include <sys/types.h>
28	#include <sys/socket.h>	41	#include <sys/socket.h>
29	#include <sys/poll.h>
30	#include <sys/wait.h>	42	#include <sys/wait.h>
31	#include <netinet/in.h>	43	#include <sys/stat.h>
32	#include <arpa/inet.h>
33	#include <errno.h>	44	#include <errno.h>
34	#include <time.h>	45	#include <time.h>
35	#include <unistd.h>	46	#include <unistd.h>
		47	#include <fcntl.h>
		48	#include <sys/socket.h>
		49
		50	#include "netcompat.h"
36		51
37	#include "pidfile.h"	52	#include "pidfile.h"
38		53
39	#include "connection.h"	54	#include "connection.h"
40	#include "util.h"	55	#include "util.h"
41	#include "vpn.h"	56	#include "vpn.h"
42		57
		58	using namespace std;
		59
		60	vpn network; // THE vpn (bad design...)
		61
43	/////////////////////////////////////////////////////////////////////////////	62	/////////////////////////////////////////////////////////////////////////////
44		63
45	const char *vpn::script_if_up (int)	64	// hopefully temporary workaround for rare buffer full conditions
		65	// if it happens, usually instantly retrying or retrying ~5ms later
		66	// is good enough with current network technologies/kernels
		67
		68	static ssize_t
		69	xsendto (int fd, const void *buf, size_t len, int flags,
		70	const struct sockaddr *sa, socklen_t salen)
		71	{
		72	ssize_t res;
		73
		74	for (int retry = 0; retry <= 13; ++retry) // ~100ms
		75	{
		76	res = sendto (fd, buf, len, flags, sa, salen);
		77
		78	if (res >= 0 \|\| errno != ENOBUFS)
		79	break;
		80
		81	struct timespec ts = { 0, 1000 * retry };
		82	nanosleep (&ts, 0);
		83	}
		84
		85	return res;
		86	}
		87
		88	/////////////////////////////////////////////////////////////////////////////
		89
		90	static void inline
		91	set_tos (int fd, int &tos_prev, int tos)
		92	{
		93	#if defined(SOL_IP) && defined(IP_TOS)
		94	if (tos_prev == tos)
		95	return;
		96
		97	tos_prev = tos;
		98	setsockopt (fd, SOL_IP, IP_TOS, &tos, sizeof tos);
		99	#endif
		100	}
		101
		102	void
		103	vpn::script_init_env ()
46	{	104	{
47	// the tunnel device mtu should be the physical mtu - overhead	105	// the tunnel device mtu should be the physical mtu - overhead
48	// the tricky part is rounding to the cipher key blocksize	106	// the tricky part is rounding to the cipher key blocksize
49	int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - MAX_OVERHEAD;	107	int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - MAX_OVERHEAD;
50	mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion	108	mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion
51	mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round	109	mtu -= mtu % BLOCK_SIZE (CIPHER); // round
52	mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again	110	mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again
53		111
54	char *env;	112	char *env;
55	asprintf (&env, "CONFBASE=%s", confbase);	113	asprintf (&env, "CONFBASE=%s", confbase); putenv (env);
56	putenv (env);
57	asprintf (&env, "NODENAME=%s", THISNODE->nodename);
58	putenv (env);
59	asprintf (&env, "NODEID=%d", THISNODE->id);
60	putenv (env);
61	asprintf (&env, "IFNAME=%s", tap->interface ());	114	asprintf (&env, "IFNAME=%s", tap->interface ()); putenv (env);
62	putenv (env);	115	asprintf (&env, "IFTYPE=%s", IFTYPE); putenv (env);
		116	asprintf (&env, "IFSUBTYPE=%s", IFSUBTYPE); putenv (env);
63	asprintf (&env, "MTU=%d", mtu);	117	asprintf (&env, "MTU=%d", mtu); putenv (env);
64	putenv (env);	118	asprintf (&env, "NODES=%d", conns.size ()); putenv (env);
65	asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x",	119	asprintf (&env, "NODEID=%d", THISNODE->id); putenv (env);
66	0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8,
67	THISNODE->id & 0xff);
68	putenv (env);
69		120
70	return ::conf.script_if_up ? ::conf.script_if_up : "if-up";	121	conns [THISNODE->id - 1]->script_init_env ("");
		122
		123	for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c)
		124	{
		125	char ext[16];
		126	snprintf (ext, 16, "_%d", (*c)->conf->id);
		127	(*c)->script_init_env (ext);
		128	}
		129	}
		130
		131	inline const char *
		132	vpn::script_if_init ()
		133	{
		134	script_init_env ();
		135
		136	return tap->if_up ();
		137	}
		138
		139	inline const char *
		140	vpn::script_if_up ()
		141	{
		142	script_init_env ();
		143
		144	return conf.config_filename (::conf.script_if_up, "if-up");
		145	}
		146
		147	int
		148	vpn::setup_socket (u8 prot, int family, int type, int proto)
		149	{
		150	int fd = socket (family, type, proto);
		151
		152	if (fd < 0)
		153	{
		154	slog (L_ERR, _("unable to create %s socket: %s."), strprotocol (prot), strerror (errno));
		155	return fd;
		156	}
		157
		158	fcntl (fd, F_SETFL, O_NONBLOCK);
		159	fcntl (fd, F_SETFD, FD_CLOEXEC);
		160
		161	#ifdef SO_MARK
		162	if (::conf.nfmark)
		163	if (setsockopt (fd, SOL_SOCKET, SO_MARK, &::conf.nfmark, sizeof ::conf.nfmark))
		164	slog (L_WARN, _("unable to set nfmark on %s socket: %s"), strprotocol (prot), strerror (errno));
		165	#endif
		166
		167	return fd;
71	}	168	}
72		169
73	int	170	int
74	vpn::setup ()	171	vpn::setup ()
75	{	172	{
76	sockinfo si;	173	int success = 0;
77		174
78	si.set (THISNODE);	175	ipv4_tos = -1;
79
80	udpv4_fd = -1;	176	ipv4_fd = -1;
81		177
82	if (THISNODE->protocols & PROT_UDPv4)	178	if (THISNODE->protocols & PROT_IPv4 && ::conf.ip_proto)
83	{	179	{
84	udpv4_fd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);	180	ipv4_fd = setup_socket (PROT_IPv4, PF_INET, SOCK_RAW, ::conf.ip_proto);
85		181
86	if (udpv4_fd < 0)	182	if (ipv4_fd < 0)
87	return -1;	183	return -1;
88		184
89	if (bind (udpv4_fd, si.sav4 (), si.salenv4 ()))	185	#if defined(SOL_IP) && defined(IP_MTU_DISCOVER)
90	{
91	slog (L_ERR, _("can't bind udpv4 to %s: %s"), (const char *)si, strerror (errno));
92	exit (1);
93	}
94
95	#ifdef IP_MTU_DISCOVER
96	// this I really consider a linux bug. I am neither connected	186	// this I really consider a linux bug. I am neither connected
97	// nor do I fragment myself. Linux still sets DF and doesn't	187	// nor do I fragment myself. Linux still sets DF and doesn't
98	// fragment for me sometimes.	188	// fragment for me sometimes.
99	{	189	{
100	int oval = IP_PMTUDISC_DONT;	190	int oval = IP_PMTUDISC_DONT;
101	setsockopt (udpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval);	191	setsockopt (ipv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval);
		192	}
		193	#endif
		194
		195	sockinfo si (THISNODE, PROT_IPv4);
		196
		197	if (bind (ipv4_fd, si.sav4 (), si.salenv4 ()))
		198	{
		199	slog (L_ERR, _("can't bind ipv4 socket on %s: %s, exiting."), (const char *)si, strerror (errno));
		200	return -1;
102	}	201	}
103	#endif	202
		203	ipv4_ev_watcher.start (ipv4_fd, EV_READ);
		204	++success;
		205	}
		206	else
		207	THISNODE->protocols &= ~PROT_IPv4;
		208
		209	udpv4_tos = -1;
		210	udpv4_fd = -1;
		211
		212	if (THISNODE->protocols & PROT_UDPv4 && THISNODE->udp_port)
		213	{
		214	udpv4_fd = setup_socket (PROT_UDPv4, PF_INET, SOCK_DGRAM, IPPROTO_UDP);
		215
		216	if (udpv4_fd < 0)
		217	return -1;
104		218
105	// standard daemon practise...	219	// standard daemon practise...
106	{	220	{
107	int oval = 1;	221	int oval = 1;
108	setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval);	222	setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval);
109	}	223	}
110		224
111	udpv4_ev_watcher.start (udpv4_fd, POLLIN);	225	#if defined(SOL_IP) && defined(IP_MTU_DISCOVER)
112	}
113
114	ipv4_fd = -1;
115	if (THISNODE->protocols & PROT_IPv4)
116	{
117	ipv4_fd = socket (PF_INET, SOCK_RAW, ::conf.ip_proto);
118
119	if (ipv4_fd < 0)
120	return -1;
121
122	if (bind (ipv4_fd, si.sav4 (), si.salenv4 ()))
123	{
124	slog (L_ERR, _("can't bind ipv4 socket to %s: %s"), (const char *)si, strerror (errno));
125	exit (1);
126	}
127
128	#ifdef IP_MTU_DISCOVER
129	// this I really consider a linux bug. I am neither connected	226	// this I really consider a linux bug. I am neither connected
130	// nor do I fragment myself. Linux still sets DF and doesn't	227	// nor do I fragment myself. Linux still sets DF and doesn't
131	// fragment for me sometimes.	228	// fragment for me sometimes.
132	{	229	{
133	int oval = IP_PMTUDISC_DONT;	230	int oval = IP_PMTUDISC_DONT;
		231	setsockopt (udpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval);
		232	}
		233	#endif
		234
		235	sockinfo si (THISNODE, PROT_UDPv4);
		236
		237	if (bind (udpv4_fd, si.sav4 (), si.salenv4 ()))
		238	{
		239	slog (L_ERR, _("can't bind udpv4 on %s: %s, exiting."), (const char *)si, strerror (errno));
		240	return -1;
		241	}
		242
		243	udpv4_ev_watcher.start (udpv4_fd, EV_READ);
		244	++success;
		245	}
		246	else
		247	THISNODE->protocols &= ~PROT_UDPv4;
		248
		249	icmpv4_tos = -1;
		250	icmpv4_fd = -1;
		251
		252	#if ENABLE_ICMP
		253	if (THISNODE->protocols & PROT_ICMPv4)
		254	{
		255	icmpv4_fd = setup_socket (PROT_ICMPv4, PF_INET, SOCK_RAW, IPPROTO_ICMP);
		256
		257	if (icmpv4_fd < 0)
		258	return -1;
		259
		260	#ifdef ICMP_FILTER
		261	{
		262	icmp_filter oval;
		263	oval.data = 0;
		264	if (::conf.icmp_type < 32)
		265	oval.data \|= 1 << ::conf.icmp_type;
		266	oval.data = ~oval.data;
		267
		268	setsockopt (icmpv4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval);
		269	}
		270	#endif
		271
		272	#if defined(SOL_IP) && defined(IP_MTU_DISCOVER)
		273	// this I really consider a linux bug. I am neither connected
		274	// nor do I fragment myself. Linux still sets DF and doesn't
		275	// fragment for me sometimes.
		276	{
		277	int oval = IP_PMTUDISC_DONT;
134	setsockopt (ipv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval);	278	setsockopt (icmpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval);
		279	}
		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;
135	}	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	}
136	#endif	353	# endif
137		354
138	ipv4_ev_watcher.start (ipv4_fd, POLLIN);	355	// standard daemon practise...
		356	{
		357	int oval = 1;
		358	setsockopt (dnsv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval);
139	}	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	/////////////////////////////////////////////////////////////////////////////
140		387
141	tap = new tap_device ();	388	tap = new tap_device ();
142	if (!tap) //D this, of course, never catches	389	if (!tap) //D this, of course, never catches
143	{	390	{
144	slog (L_ERR, _("cannot create network interface '%s'"), conf.ifname);	391	slog (L_ERR, _("cannot create network interface '%s'."), conf.ifname);
145	exit (1);	392	return -1;
146	}	393	}
147		394
148	run_script (run_script_cb (this, &vpn::script_if_up), true);	395	fcntl (tap->fd, F_SETFD, FD_CLOEXEC);
149		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
150	tap_ev_watcher.start (tap->fd, POLLIN);	415	tap_ev_watcher.start (tap->fd, EV_READ);
151
152	reconnect_all ();
153		416
154	return 0;	417	return 0;
155	}	418	}
156		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
157	void	548	void
158	vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)	549	vpn::inject_data_packet (tap_packet *pkt, int dst)
159	{	550	{
160	setsockopt (ipv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos);	551	if (dst)
161	sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ());	552	{
162	}	553	// unicast
163		554	if (dst != THISNODE->id)
164	void	555	conns[dst - 1]->inject_data_packet (pkt);
165	vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos)	556	}
166	{	557	else
167	setsockopt (udpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos);	558	{
168	sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ());	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	}
169	}	565	}
170		566
171	void	567	void
172	vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi)	568	vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi)
173	{	569	{
174	unsigned int src = pkt->src ();	570	unsigned int src = pkt->src ();
175	unsigned int dst = pkt->dst ();	571	unsigned int dst = pkt->dst ();
176		572
177	slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d"),	573	slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d."),
178	(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len);	574	(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len);
179		575
180	if (src == 0 \|\| src > conns.size ()	576	if (src == 0 \|\| src > conns.size ()
181	\|\| dst > conns.size ()	577	\|\| dst > conns.size ()
182	\|\| pkt->typ () >= vpn_packet::PT_MAX)	578	\|\| pkt->typ () >= vpn_packet::PT_MAX)
183	slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)"),	579	slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."),
184	(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ());	580	(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ());
185	else	581	else
186	{	582	{
187	connection *c = conns[src - 1];	583	connection *c = conns[src - 1];
188		584
189	if (dst == 0 && !THISNODE->routerprio)	585	if (dst == 0)
190	slog (L_WARN, _("%s(%s): received broadcast, but we are no router"),	586	slog (L_WARN, _("%s(%s): received broadcast (protocol violation)."),
191	c->conf->nodename, (const char *)rsi);	587	c->conf->nodename, (const char *)rsi);
192	else if (dst != 0 && dst != THISNODE->id)	588	else if (dst != THISNODE->id)
193	// FORWARDING NEEDED ;)	589	{
		590	if (THISNODE->routerprio)
		591	// the tos setting gets lost here. who cares.
		592	conns[dst - 1]->inject_vpn_packet (pkt);
		593	else
194	slog (L_WARN,	594	slog (L_WARN,
195	_("received frame for node %d ('%s') from %s, but this is node %d ('%s')"),	595	_("%s(%s): request to forward packet to %s, but we are no router (config mismatch?)."),
		596	c->conf->nodename, (const char *)rsi,
196	dst, conns[dst - 1]->conf->nodename,	597	conns[dst - 1]->conf->nodename);
197	(const char *)rsi,	598	}
198	THISNODE->id, THISNODE->nodename);
199	else	599	else
200	c->recv_vpn_packet (pkt, rsi);	600	c->recv_vpn_packet (pkt, rsi);
201	}	601	}
202	}	602	}
203		603
204	void	604	bool
205	vpn::udpv4_ev (short revents)	605	vpn::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos)
206	{	606	{
207	if (revents & (POLLIN \| POLLERR))	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)
208	{	638	{
209	vpn_packet *pkt = new vpn_packet;	639	vpn_packet *pkt = new vpn_packet;
210	struct sockaddr_in sa;	640	struct sockaddr_in sa;
211	socklen_t sa_len = sizeof (sa);	641	socklen_t sa_len = sizeof (sa);
212	int len;	642	int len;
213		643
214	len = recvfrom (udpv4_fd, &((pkt)[0]), MAXSIZE, 0, (sockaddr )&sa, &sa_len);	644	len = recvfrom (w.fd, &((pkt)[0]), MAXSIZE, 0, (sockaddr )&sa, &sa_len);
215		645
216	sockinfo si(sa);	646	sockinfo si(sa, PROT_IPv4);
217		647
218	if (len > 0)	648	if (len > 0)
219	{	649	{
220	pkt->len = len;	650	pkt->len = len;
221		651
		652	// raw sockets deliver the ipv4 header, but don't expect it on sends
		653	pkt->skip_hdr (pkt->ipv4_hdr_len ());
		654
222	recv_vpn_packet (pkt, si);	655	recv_vpn_packet (pkt, si);
223	}	656	}
224	else	657	else
225	{	658	{
226	// probably ECONNRESET or somesuch	659	// probably ECONNRESET or somesuch
227	slog (L_DEBUG, _("%s: %s"), (const char *)si, strerror (errno));	660	slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno));
228	}	661	}
229		662
230	delete pkt;	663	delete pkt;
231	}	664	}
232	else if (revents & POLLHUP)
233	{
234	// this cannot ;) happen on udp sockets
235	slog (L_ERR, _("FATAL: POLLHUP on udp v4 fd, terminating."));
236	exit (1);
237	}
238	else	665	else
239	{	666	{
240	slog (L_ERR,	667	slog (L_ERR,
241	_("FATAL: unknown revents %08x in socket, terminating\n"),	668	_("FATAL: unknown revents %08x in socket, exiting.\n"),
242	revents);	669	revents);
243	exit (1);	670	exit (EXIT_FAILURE);
244	}	671	}
245	}	672	}
246		673
247	void	674	#if ENABLE_ICMP
248	vpn::ipv4_ev (short revents)	675	inline void
		676	vpn::icmpv4_ev (ev::io &w, int revents)
249	{	677	{
250	if (revents & (POLLIN \| POLLERR))	678	if (revents & EV_READ)
251	{	679	{
252	vpn_packet *pkt = new vpn_packet;	680	vpn_packet *pkt = new vpn_packet;
253	struct sockaddr_in sa;	681	struct sockaddr_in sa;
254	socklen_t sa_len = sizeof (sa);	682	socklen_t sa_len = sizeof (sa);
255	int len;	683	int len;
256		684
257	len = recvfrom (ipv4_fd, &((pkt)[0]), MAXSIZE, 0, (sockaddr )&sa, &sa_len);	685	len = recvfrom (w.fd, &((pkt)[0]), MAXSIZE, 0, (sockaddr )&sa, &sa_len);
258		686
259	sockinfo si(sa, PROT_IPv4);	687	sockinfo si(sa, PROT_ICMPv4);
260		688
261	if (len > 0)	689	if (len > 0)
262	{	690	{
263	pkt->len = len;	691	pkt->len = len;
264		692
		693	icmp_header hdr = (icmp_header )&((*pkt)[IP_OVERHEAD]);
		694
		695	if (hdr->type == ::conf.icmp_type
		696	&& hdr->code == 255)
		697	{
265	// raw sockets deliver the ipv4, but don't expect it on sends	698	// raw sockets deliver the ipv4, but don't expect it on sends
266	// this is slow, but...	699	// this is slow, but...
267	pkt->skip_hdr (IP_OVERHEAD);	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;
268		740
269	recv_vpn_packet (pkt, si);	741	recv_vpn_packet (pkt, si);
270	}	742	}
271	else	743	else
272	{	744	{
273	// probably ECONNRESET or somesuch	745	// probably ECONNRESET or somesuch
274	slog (L_DEBUG, _("%s: %s"), (const char *)si, strerror (errno));	746	slog (L_DEBUG, _("%s: fd %d, %s."), (const char *)si, w.fd, strerror (errno));
275	}	747	}
276		748
277	delete pkt;	749	delete pkt;
278	}	750	}
279	else if (revents & POLLHUP)
280	{
281	// this cannot ;) happen on udp sockets
282	slog (L_ERR, _("FATAL: POLLHUP on ipv4 fd, terminating."));
283	exit (1);
284	}
285	else	751	else
286	{	752	{
287	slog (L_ERR,	753	slog (L_ERR,
288	_("FATAL: unknown revents %08x in socket, terminating\n"),	754	_("FATAL: unknown revents %08x in socket, exiting.\n"),
289	revents);	755	revents);
290	exit (1);	756	exit (EXIT_FAILURE);
291	}	757	}
292	}	758	}
293		759
294	void	760	inline void
295	vpn::tap_ev (short revents)	761	vpn::tap_ev (ev::io &w, int revents)
296	{	762	{
297	if (revents & POLLIN)	763	if (revents & EV_READ)
298	{	764	{
299	/* process data */	765	/* process data */
300	tap_packet *pkt;	766	tap_packet *pkt;
301		767
302	pkt = tap->recv ();	768	pkt = tap->recv ();
303		769
		770	if (!pkt)
		771	return;
		772
		773	if (pkt->len > 14)
		774	{
304	int dst = mac2id (pkt->dst);	775	int dst = mac2id (pkt->dst);
305	int src = mac2id (pkt->src);	776	int src = mac2id (pkt->src);
306		777
307	if (src != THISNODE->id)	778	if (src != THISNODE->id)
308	{
309	slog (L_ERR, _("FATAL: tap packet not originating on current node received, terminating."));
310	exit (1);
311	}
312
313	if (dst == THISNODE->id)
314	{
315	slog (L_ERR, _("FATAL: tap packet destined for current node received, terminating."));
316	exit (1);
317	}
318
319	if (dst > conns.size ())
320	slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst);
321	else
322	{
323	if (dst)
324	{	779	{
325	// unicast	780	slog (L_ERR, _("FATAL: tap packet not originating on current node received (if-up script not working properly?), exiting."));
326	if (dst != THISNODE->id)	781	exit (EXIT_FAILURE);
327	conns[dst - 1]->inject_data_packet (pkt);
328	}	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);
329	else	792	else
330	{
331	// broadcast, first check router, then self, then english
332	connection *router = find_router ();
333
334	if (router)
335	router->inject_data_packet (pkt, true);	793	inject_data_packet (pkt, dst);
336	else
337	for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c)
338	if ((*c)->conf != THISNODE)
339	(*c)->inject_data_packet (pkt);
340	}
341	}	794	}
342		795
343	delete pkt;	796	delete pkt;
344	}
345	else if (revents & (POLLHUP \| POLLERR))
346	{
347	slog (L_ERR, _("FATAL: POLLHUP or POLLERR on network device fd, terminating."));
348	exit (1);
349	}	797	}
350	else	798	else
351	abort ();	799	abort ();
352	}	800	}
353		801
354	void	802	inline void
355	vpn::event_cb (tstamp &ts)	803	vpn::event_cb (ev::timer &w, int)
356	{	804	{
357	if (events)	805	if (events)
358	{	806	{
359	if (events & EVENT_SHUTDOWN)	807	if (events & EVENT_SHUTDOWN)
360	{	808	{
361	slog (L_INFO, _("preparing shutdown..."));	809	slog (L_INFO, _("preparing shutdown..."));
362		810
363	shutdown_all ();	811	shutdown_all ();
364
365	remove_pid (pidfilename);	812	remove_pid (conf.pidfilename);
366
367	slog (L_INFO, _("terminating"));	813	slog (L_INFO, _("exiting."));
368		814	exit (EXIT_SUCCESS);
369	exit (0);
370	}	815	}
371		816
372	if (events & EVENT_RECONNECT)	817	if (events & EVENT_RECONNECT)
373	{	818	{
374	slog (L_INFO, _("forced reconnect"));	819	slog (L_INFO, _("forced reconnect."));
375		820
376	reconnect_all ();	821	reconnect_all ();
377	}	822	}
378		823
379	events = 0;	824	events = 0;
380	}	825	}
381
382	ts = TSTAMP_CANCEL;
383	}	826	}
384		827
385	void	828	void
386	vpn::shutdown_all ()	829	vpn::shutdown_all ()
387	{	830	{
397		840
398	conns.clear ();	841	conns.clear ();
399		842
400	connection_init ();	843	connection_init ();
401		844
402	for (configuration::node_vector::iterator i = conf.nodes.begin ();	845	for (configuration::node_vector::iterator i = conf.nodes.begin (); i != conf.nodes.end (); ++i)
403	i != conf.nodes.end (); ++i)	846	conns.push_back (new connection (this, *i));
404	{
405	connection *conn = new connection (this);
406		847
407	conn->conf = *i;	848	for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c)
408	conns.push_back (conn);
409
410	conn->establish_connection ();	849	(*c)->establish_connection ();
411	}
412	}	850	}
413		851
414	connection *vpn::find_router ()	852	bool
		853	vpn::can_direct (conf_node src, conf_node dst) const
415	{	854	{
416	u32 prio = 0;	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	{
417	connection *router = 0;	867	connection *router = 0;
418		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	{
419	for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i)	917	for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i)
420	{	918	{
421	connection c = i;	919	connection o = i;
422		920
423	if (c->conf->routerprio > prio	921	if (o->si.valid ()
424	&& c->connectmode == conf_node::C_ALWAYS	922	&& c->si != o->si
425	&& c->conf != THISNODE	923	&& c == find_router_for (o)
426	&& c->ictx && c->octx)	924	&& !can_direct (THISNODE, o->conf))
427	{
428	prio = c->conf->routerprio;
429	router = c;
430	}	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	}
431	}	930	}
432
433	return router;
434	}	931	}
435		932
436	void vpn::connect_request (int id)	933	void
		934	vpn::send_connect_request (connection *c)
437	{	935	{
438	connection *c = find_router ();	936	connection *r = find_router_for (c);
439		937
440	if (c)	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);
441	c->connect_request (id);	942	r->send_connect_request (c->conf->id);
442	//else // does not work, because all others must connect to the same router	943	}
443	// // no router found, aggressively connect to all routers	944	else
444	// for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i)	945	slog (L_DEBUG, _("%s: no way to connect and no router found: unable to connect at this time."),
445	// if ((*i)->conf->routerprio)	946	c->conf->nodename);
446	// (*i)->establish_connection ();
447	}	947	}
448		948
449	void	949	void
450	connection::dump_status ()	950	connection::dump_status ()
451	{	951	{
452	slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id);	952	slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id);
453	slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"),	953	slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"),
454	connectmode, conf->connectmode, (const char *)si, (int)prot_minor);	954	connectmode, conf->connectmode, (const char *)si, (int)prot_minor);
455	slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"),	955	slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"),
456	(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt);	956	(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt);
457	slog (L_NOTICE, _(" establish_conn %ld / rekey %ld / keepalive %ld"),
458	(long)(establish_connection.at), (long)(rekey.at), (long)(keepalive.at));
459	}	957	}
460		958
461	void	959	void
462	vpn::dump_status ()	960	vpn::dump_status ()
463	{	961	{
464	slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)NOW);	962	slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)ev_now ());
465		963
466	for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c)	964	for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c)
467	(*c)->dump_status ();	965	(*c)->dump_status ();
468		966
469	slog (L_NOTICE, _("END status dump"));	967	slog (L_NOTICE, _("END status dump"));
470	}	968	}
471		969
472	vpn::vpn (void)	970	vpn::vpn (void)
		971	{
		972	event .set<vpn, &vpn::event_cb > (this);
473	: udpv4_ev_watcher(this, &vpn::udpv4_ev)	973	udpv4_ev_watcher .set<vpn, &vpn::udpv4_ev > (this);
474	, ipv4_ev_watcher(this, &vpn::ipv4_ev)	974	ipv4_ev_watcher .set<vpn, &vpn::ipv4_ev > (this);
475	, tap_ev_watcher(this, &vpn::tap_ev)	975	#if ENABLE_TCP
476	, event(this, &vpn::event_cb)	976	tcpv4_ev_watcher .set<vpn, &vpn::tcpv4_ev > (this);
477	{	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);
478	}	985	}
479		986
480	vpn::~vpn ()	987	vpn::~vpn ()
481	{	988	{
482	}	989	}

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing gvpe/src/vpn.C (file contents): Revision 1.1 by pcg, Wed Apr 2 03:25:17 2003 UTC vs. Revision 1.70 by root, Thu Oct 6 03:03:09 2022 UTC

Diff Legend

Comparing gvpe/src/vpn.C (file contents):
Revision 1.1 by pcg, Wed Apr 2 03:25:17 2003 UTC vs.
Revision 1.70 by root, Thu Oct 6 03:03:09 2022 UTC