1 |
/* |
2 |
vpn.C -- handle the protocol, encryption, handshaking etc. |
3 |
Copyright (C) 2003-2008 Marc Lehmann <gvpe@schmorp.de> |
4 |
|
5 |
This file is part of GVPE. |
6 |
|
7 |
GVPE is free software; you can redistribute it and/or modify it |
8 |
under the terms of the GNU General Public License as published by the |
9 |
Free Software Foundation; either version 3 of the License, or (at your |
10 |
option) any later version. |
11 |
|
12 |
This program is distributed in the hope that it will be useful, but |
13 |
WITHOUT ANY WARRANTY; without even the implied warranty of |
14 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General |
15 |
Public License for more details. |
16 |
|
17 |
You should have received a copy of the GNU General Public License along |
18 |
with this program; if not, see <http://www.gnu.org/licenses/>. |
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. |
30 |
*/ |
31 |
|
32 |
#include "config.h" |
33 |
|
34 |
#include <list> |
35 |
|
36 |
#include <cstdio> |
37 |
#include <cstring> |
38 |
#include <cstdlib> |
39 |
|
40 |
#include <sys/types.h> |
41 |
#include <sys/socket.h> |
42 |
#include <sys/wait.h> |
43 |
#include <errno.h> |
44 |
#include <time.h> |
45 |
#include <unistd.h> |
46 |
#include <fcntl.h> |
47 |
#include <sys/socket.h> |
48 |
|
49 |
#include "netcompat.h" |
50 |
|
51 |
#include "pidfile.h" |
52 |
|
53 |
#include "connection.h" |
54 |
#include "util.h" |
55 |
#include "vpn.h" |
56 |
|
57 |
vpn network; // THE vpn (bad design...) |
58 |
|
59 |
///////////////////////////////////////////////////////////////////////////// |
60 |
|
61 |
static void inline |
62 |
set_tos (int fd, int &tos_prev, int tos) |
63 |
{ |
64 |
#if defined(SOL_IP) && defined(IP_TOS) |
65 |
if (tos_prev == tos) |
66 |
return; |
67 |
|
68 |
tos_prev = tos; |
69 |
setsockopt (fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
70 |
#endif |
71 |
} |
72 |
|
73 |
void |
74 |
vpn::script_init_env () |
75 |
{ |
76 |
// the tunnel device mtu should be the physical mtu - overhead |
77 |
// the tricky part is rounding to the cipher key blocksize |
78 |
int mtu = conf.mtu - ETH_OVERHEAD - VPE_OVERHEAD - MAX_OVERHEAD; |
79 |
mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
80 |
mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round |
81 |
mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
82 |
|
83 |
char *env; |
84 |
asprintf (&env, "CONFBASE=%s", confbase); putenv (env); |
85 |
asprintf (&env, "IFNAME=%s", tap->interface ()); putenv (env); |
86 |
asprintf (&env, "IFTYPE=%s", IFTYPE); putenv (env); |
87 |
asprintf (&env, "IFSUBTYPE=%s", IFSUBTYPE); putenv (env); |
88 |
asprintf (&env, "MTU=%d", mtu); putenv (env); |
89 |
asprintf (&env, "NODES=%d", conns.size ()); putenv (env); |
90 |
asprintf (&env, "NODEID=%d", THISNODE->id); putenv (env); |
91 |
|
92 |
conns [THISNODE->id - 1]->script_init_env (""); |
93 |
|
94 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
95 |
{ |
96 |
char ext[16]; |
97 |
snprintf (ext, 16, "_%d", (*c)->conf->id); |
98 |
(*c)->script_init_env (ext); |
99 |
} |
100 |
} |
101 |
|
102 |
inline const char * |
103 |
vpn::script_if_init () |
104 |
{ |
105 |
script_init_env (); |
106 |
|
107 |
return tap->if_up (); |
108 |
} |
109 |
|
110 |
inline const char * |
111 |
vpn::script_if_up () |
112 |
{ |
113 |
script_init_env (); |
114 |
|
115 |
char *filename; |
116 |
asprintf (&filename, |
117 |
"%s/%s", |
118 |
confbase, |
119 |
::conf.script_if_up ? ::conf.script_if_up : "if-up"); |
120 |
|
121 |
return filename; |
122 |
} |
123 |
|
124 |
int |
125 |
vpn::setup_socket (u8 prot, int family, int type, int proto) |
126 |
{ |
127 |
int fd = socket (family, type, proto); |
128 |
|
129 |
if (fd < 0) |
130 |
{ |
131 |
slog (L_ERR, _("unable to create %s socket: %s."), strprotocol (prot), strerror (errno)); |
132 |
return fd; |
133 |
} |
134 |
|
135 |
fcntl (fd, F_SETFL, O_NONBLOCK); |
136 |
fcntl (fd, F_SETFD, FD_CLOEXEC); |
137 |
|
138 |
#ifdef SO_MARK |
139 |
if (::conf.nfmark) |
140 |
setsockopt (ipv4_fd, SOL_SOCKET, SO_MARK, &::conf.nfmark, sizeof ::conf.nfmark); |
141 |
#endif |
142 |
|
143 |
return fd; |
144 |
} |
145 |
|
146 |
int |
147 |
vpn::setup () |
148 |
{ |
149 |
int success = 0; |
150 |
|
151 |
ipv4_tos = -1; |
152 |
ipv4_fd = -1; |
153 |
|
154 |
if (THISNODE->protocols & PROT_IPv4 && ::conf.ip_proto) |
155 |
{ |
156 |
ipv4_fd = setup_socket (PROT_IPv4, PF_INET, SOCK_RAW, ::conf.ip_proto); |
157 |
|
158 |
if (ipv4_fd < 0) |
159 |
return -1; |
160 |
|
161 |
#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
162 |
// this I really consider a linux bug. I am neither connected |
163 |
// nor do I fragment myself. Linux still sets DF and doesn't |
164 |
// fragment for me sometimes. |
165 |
{ |
166 |
int oval = IP_PMTUDISC_DONT; |
167 |
setsockopt (ipv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
168 |
} |
169 |
#endif |
170 |
|
171 |
sockinfo si (THISNODE, PROT_IPv4); |
172 |
|
173 |
if (bind (ipv4_fd, si.sav4 (), si.salenv4 ())) |
174 |
{ |
175 |
slog (L_ERR, _("can't bind ipv4 socket on %s: %s, exiting."), (const char *)si, strerror (errno)); |
176 |
return -1; |
177 |
} |
178 |
|
179 |
ipv4_ev_watcher.start (ipv4_fd, EV_READ); |
180 |
++success; |
181 |
} |
182 |
else |
183 |
THISNODE->protocols &= ~PROT_IPv4; |
184 |
|
185 |
udpv4_tos = -1; |
186 |
udpv4_fd = -1; |
187 |
|
188 |
if (THISNODE->protocols & PROT_UDPv4 && THISNODE->udp_port) |
189 |
{ |
190 |
udpv4_fd = setup_socket (PROT_UDPv4, PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
191 |
|
192 |
if (udpv4_fd < 0) |
193 |
return -1; |
194 |
|
195 |
// standard daemon practise... |
196 |
{ |
197 |
int oval = 1; |
198 |
setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
199 |
} |
200 |
|
201 |
#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
202 |
// this I really consider a linux bug. I am neither connected |
203 |
// nor do I fragment myself. Linux still sets DF and doesn't |
204 |
// fragment for me sometimes. |
205 |
{ |
206 |
int oval = IP_PMTUDISC_DONT; |
207 |
setsockopt (udpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
208 |
} |
209 |
#endif |
210 |
|
211 |
sockinfo si (THISNODE, PROT_UDPv4); |
212 |
|
213 |
if (bind (udpv4_fd, si.sav4 (), si.salenv4 ())) |
214 |
{ |
215 |
slog (L_ERR, _("can't bind udpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
216 |
return -1; |
217 |
} |
218 |
|
219 |
udpv4_ev_watcher.start (udpv4_fd, EV_READ); |
220 |
++success; |
221 |
} |
222 |
else |
223 |
THISNODE->protocols &= ~PROT_UDPv4; |
224 |
|
225 |
icmpv4_tos = -1; |
226 |
icmpv4_fd = -1; |
227 |
|
228 |
#if ENABLE_ICMP |
229 |
if (THISNODE->protocols & PROT_ICMPv4) |
230 |
{ |
231 |
icmpv4_fd = setup_socket (PROT_ICMPv4, PF_INET, SOCK_RAW, IPPROTO_ICMP); |
232 |
|
233 |
if (icmpv4_fd < 0) |
234 |
return -1; |
235 |
|
236 |
#ifdef ICMP_FILTER |
237 |
{ |
238 |
icmp_filter oval; |
239 |
oval.data = 0xffffffff; |
240 |
if (::conf.icmp_type < 32) |
241 |
oval.data &= ~(1 << ::conf.icmp_type); |
242 |
|
243 |
setsockopt (icmpv4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval); |
244 |
} |
245 |
#endif |
246 |
|
247 |
#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
248 |
// this I really consider a linux bug. I am neither connected |
249 |
// nor do I fragment myself. Linux still sets DF and doesn't |
250 |
// fragment for me sometimes. |
251 |
{ |
252 |
int oval = IP_PMTUDISC_DONT; |
253 |
setsockopt (icmpv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
254 |
} |
255 |
#endif |
256 |
|
257 |
sockinfo si (THISNODE, PROT_ICMPv4); |
258 |
|
259 |
if (bind (icmpv4_fd, si.sav4 (), si.salenv4 ())) |
260 |
{ |
261 |
slog (L_ERR, _("can't bind icmpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
262 |
return -1; |
263 |
} |
264 |
|
265 |
icmpv4_ev_watcher.start (icmpv4_fd, EV_READ); |
266 |
++success; |
267 |
} |
268 |
#endif |
269 |
|
270 |
tcpv4_fd = -1; |
271 |
|
272 |
#if ENABLE_TCP |
273 |
if (THISNODE->protocols & PROT_TCPv4 && THISNODE->tcp_port) |
274 |
{ |
275 |
tcpv4_fd = setup_socket (PROT_TCPv4, PF_INET, SOCK_STREAM, IPPROTO_TCP); |
276 |
|
277 |
if (tcpv4_fd < 0) |
278 |
return -1; |
279 |
|
280 |
// standard daemon practise... |
281 |
{ |
282 |
int oval = 1; |
283 |
setsockopt (tcpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
284 |
} |
285 |
|
286 |
sockinfo si (THISNODE, PROT_TCPv4); |
287 |
|
288 |
if (bind (tcpv4_fd, si.sav4 (), si.salenv4 ())) |
289 |
{ |
290 |
slog (L_ERR, _("can't bind tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
291 |
return -1; |
292 |
} |
293 |
|
294 |
if (listen (tcpv4_fd, 5)) |
295 |
{ |
296 |
slog (L_ERR, _("can't listen tcpv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
297 |
return -1; |
298 |
} |
299 |
|
300 |
tcpv4_ev_watcher.start (tcpv4_fd, EV_READ); |
301 |
++success; |
302 |
} |
303 |
else |
304 |
THISNODE->protocols &= ~PROT_TCPv4; |
305 |
#endif |
306 |
|
307 |
dnsv4_tos = -1; |
308 |
dnsv4_fd = -1; |
309 |
|
310 |
#if ENABLE_DNS |
311 |
if (THISNODE->protocols & PROT_DNSv4) |
312 |
{ |
313 |
dns_forwarder.set (::conf.dns_forw_host, ::conf.dns_forw_port, PROT_DNSv4); |
314 |
|
315 |
dnsv4_fd = setup_socket (PROT_DNSv4, PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
316 |
|
317 |
if (dnsv4_fd < 0) |
318 |
return -1; |
319 |
|
320 |
# if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
321 |
// this I really consider a linux bug. I am neither connected |
322 |
// nor do I fragment myself. Linux still sets DF and doesn't |
323 |
// fragment for me sometimes. |
324 |
{ |
325 |
int oval = IP_PMTUDISC_DONT; |
326 |
setsockopt (dnsv4_fd, SOL_IP, IP_MTU_DISCOVER, &oval, sizeof oval); |
327 |
} |
328 |
# endif |
329 |
|
330 |
// standard daemon practise... |
331 |
{ |
332 |
int oval = 1; |
333 |
setsockopt (dnsv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
334 |
} |
335 |
|
336 |
sockinfo si (THISNODE->dns_hostname, |
337 |
THISNODE->dns_hostname ? THISNODE->dns_port : 0, |
338 |
PROT_DNSv4); |
339 |
|
340 |
if (bind (dnsv4_fd, si.sav4 (), si.salenv4 ())) |
341 |
{ |
342 |
slog (L_ERR, _("can't bind dnsv4 on %s: %s, exiting."), (const char *)si, strerror (errno)); |
343 |
return -1; |
344 |
} |
345 |
|
346 |
dnsv4_ev_watcher.start (dnsv4_fd, EV_READ); |
347 |
++success; |
348 |
} |
349 |
#endif |
350 |
|
351 |
///////////////////////////////////////////////////////////////////////////// |
352 |
|
353 |
if (!success) |
354 |
{ |
355 |
slog (L_ERR, _("no protocols enabled.")); |
356 |
return -1; |
357 |
} |
358 |
|
359 |
reconnect_all (); |
360 |
|
361 |
///////////////////////////////////////////////////////////////////////////// |
362 |
|
363 |
tap = new tap_device (); |
364 |
if (!tap) //D this, of course, never catches |
365 |
{ |
366 |
slog (L_ERR, _("cannot create network interface '%s'."), conf.ifname); |
367 |
return -1; |
368 |
} |
369 |
|
370 |
fcntl (tap->fd, F_SETFD, FD_CLOEXEC); |
371 |
|
372 |
run_script_cb cb; |
373 |
cb.set<vpn, &vpn::script_if_init> (this); |
374 |
|
375 |
if (tap->if_up () && |
376 |
!run_script (cb, true)) |
377 |
{ |
378 |
slog (L_ERR, _("interface initialization command '%s' failed."), |
379 |
tap->if_up ()); |
380 |
return -1; |
381 |
} |
382 |
|
383 |
cb.set<vpn, &vpn::script_if_up> (this); |
384 |
if (!run_script (cb, true)) |
385 |
{ |
386 |
slog (L_ERR, _("if-up command execution failed.")); |
387 |
return -1; |
388 |
} |
389 |
|
390 |
tap_ev_watcher.start (tap->fd, EV_READ); |
391 |
|
392 |
return 0; |
393 |
} |
394 |
|
395 |
bool |
396 |
vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
397 |
{ |
398 |
set_tos (ipv4_fd, ipv4_tos, tos); |
399 |
sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
400 |
|
401 |
return true; |
402 |
} |
403 |
|
404 |
static u16 |
405 |
ipv4_checksum (u16 *data, unsigned int len) |
406 |
{ |
407 |
// use 32 bit accumulator and fold back carry bits at the end |
408 |
u32 sum = 0; |
409 |
|
410 |
while (len > 1) |
411 |
{ |
412 |
sum += *data++; |
413 |
len -= 2; |
414 |
} |
415 |
|
416 |
// odd byte left? |
417 |
if (len) |
418 |
sum += *(u8 *)data; |
419 |
|
420 |
// add back carry bits |
421 |
sum = (sum >> 16) + (sum & 0xffff); // lo += hi |
422 |
sum += (sum >> 16); // carry |
423 |
|
424 |
return ~sum; |
425 |
} |
426 |
|
427 |
#if ENABLE_ICMP |
428 |
bool |
429 |
vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
430 |
{ |
431 |
pkt->unshift_hdr (4); |
432 |
|
433 |
icmp_header *hdr = (icmp_header *)&((*pkt)[0]); |
434 |
hdr->type = ::conf.icmp_type; |
435 |
hdr->code = 255; |
436 |
hdr->checksum = 0; |
437 |
hdr->checksum = ipv4_checksum ((u16 *)hdr, pkt->len); |
438 |
|
439 |
set_tos (icmpv4_fd, icmpv4_tos, tos); |
440 |
sendto (icmpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
441 |
|
442 |
return true; |
443 |
} |
444 |
#endif |
445 |
|
446 |
bool |
447 |
vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
448 |
{ |
449 |
set_tos (udpv4_fd, udpv4_tos, tos); |
450 |
sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
451 |
|
452 |
return true; |
453 |
} |
454 |
|
455 |
void |
456 |
vpn::inject_data_packet (tap_packet *pkt, int dst) |
457 |
{ |
458 |
if (dst) |
459 |
{ |
460 |
// unicast |
461 |
if (dst != THISNODE->id) |
462 |
conns[dst - 1]->inject_data_packet (pkt); |
463 |
} |
464 |
else |
465 |
{ |
466 |
// broadcast, this is ugly, but due to the security policy |
467 |
// we have to connect to all hosts... |
468 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
469 |
if ((*c)->conf != THISNODE) |
470 |
(*c)->inject_data_packet (pkt); |
471 |
} |
472 |
} |
473 |
|
474 |
void |
475 |
vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
476 |
{ |
477 |
unsigned int src = pkt->src (); |
478 |
unsigned int dst = pkt->dst (); |
479 |
|
480 |
slog (L_NOISE, _("<<?/%s received possible vpn packet type %d from %d to %d, length %d."), |
481 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst (), pkt->len); |
482 |
|
483 |
if (src == 0 || src > conns.size () |
484 |
|| dst > conns.size () |
485 |
|| pkt->typ () >= vpn_packet::PT_MAX) |
486 |
slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."), |
487 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ()); |
488 |
else if (dst > conns.size ()) |
489 |
slog (L_WARN, _("(%s): received corrupted packet type %d (src %d, dst %d)."), |
490 |
(const char *)rsi, pkt->typ (), pkt->src (), pkt->dst ()); |
491 |
else |
492 |
{ |
493 |
connection *c = conns[src - 1]; |
494 |
|
495 |
if (dst == 0) |
496 |
slog (L_WARN, _("%s(%s): received broadcast (protocol violation)."), |
497 |
c->conf->nodename, (const char *)rsi); |
498 |
else if (dst != THISNODE->id) |
499 |
{ |
500 |
if (THISNODE->routerprio) |
501 |
// the tos setting gets lost here. who cares. |
502 |
conns[dst - 1]->inject_vpn_packet (pkt); |
503 |
else |
504 |
slog (L_WARN, |
505 |
_("%s(%s): request to forward packet to %s, but we are no router (config mismatch?)."), |
506 |
c->conf->nodename, (const char *)rsi, |
507 |
conns[dst - 1]->conf->nodename); |
508 |
} |
509 |
else |
510 |
c->recv_vpn_packet (pkt, rsi); |
511 |
} |
512 |
} |
513 |
|
514 |
bool |
515 |
vpn::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
516 |
{ |
517 |
switch (si.prot) |
518 |
{ |
519 |
case PROT_IPv4: |
520 |
return send_ipv4_packet (pkt, si, tos); |
521 |
|
522 |
case PROT_UDPv4: |
523 |
return send_udpv4_packet (pkt, si, tos); |
524 |
|
525 |
#if ENABLE_TCP |
526 |
case PROT_TCPv4: |
527 |
return send_tcpv4_packet (pkt, si, tos); |
528 |
#endif |
529 |
#if ENABLE_ICMP |
530 |
case PROT_ICMPv4: |
531 |
return send_icmpv4_packet (pkt, si, tos); |
532 |
#endif |
533 |
#if ENABLE_DNS |
534 |
case PROT_DNSv4: |
535 |
return send_dnsv4_packet (pkt, si, tos); |
536 |
#endif |
537 |
default: |
538 |
slog (L_CRIT, _("%s: FATAL: trying to send packet with unsupported protocol."), (const char *)si); |
539 |
} |
540 |
|
541 |
return false; |
542 |
} |
543 |
|
544 |
inline void |
545 |
vpn::ipv4_ev (ev::io &w, int revents) |
546 |
{ |
547 |
if (revents & EV_READ) |
548 |
{ |
549 |
vpn_packet *pkt = new vpn_packet; |
550 |
struct sockaddr_in sa; |
551 |
socklen_t sa_len = sizeof (sa); |
552 |
int len; |
553 |
|
554 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
555 |
|
556 |
sockinfo si(sa, PROT_IPv4); |
557 |
|
558 |
if (len > 0) |
559 |
{ |
560 |
pkt->len = len; |
561 |
|
562 |
// raw sockets deliver the ipv4 header, but don't expect it on sends |
563 |
pkt->skip_hdr (IP_OVERHEAD); |
564 |
|
565 |
recv_vpn_packet (pkt, si); |
566 |
} |
567 |
else |
568 |
{ |
569 |
// probably ECONNRESET or somesuch |
570 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
571 |
} |
572 |
|
573 |
delete pkt; |
574 |
} |
575 |
else |
576 |
{ |
577 |
slog (L_ERR, |
578 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
579 |
revents); |
580 |
exit (EXIT_FAILURE); |
581 |
} |
582 |
} |
583 |
|
584 |
#if ENABLE_ICMP |
585 |
inline void |
586 |
vpn::icmpv4_ev (ev::io &w, int revents) |
587 |
{ |
588 |
if (revents & EV_READ) |
589 |
{ |
590 |
vpn_packet *pkt = new vpn_packet; |
591 |
struct sockaddr_in sa; |
592 |
socklen_t sa_len = sizeof (sa); |
593 |
int len; |
594 |
|
595 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
596 |
|
597 |
sockinfo si(sa, PROT_ICMPv4); |
598 |
|
599 |
if (len > 0) |
600 |
{ |
601 |
pkt->len = len; |
602 |
|
603 |
icmp_header *hdr = (icmp_header *)&((*pkt)[IP_OVERHEAD]); |
604 |
|
605 |
if (hdr->type == ::conf.icmp_type |
606 |
&& hdr->code == 255) |
607 |
{ |
608 |
// raw sockets deliver the ipv4, but don't expect it on sends |
609 |
// this is slow, but... |
610 |
pkt->skip_hdr (ICMP_OVERHEAD); |
611 |
|
612 |
recv_vpn_packet (pkt, si); |
613 |
} |
614 |
} |
615 |
else |
616 |
{ |
617 |
// probably ECONNRESET or somesuch |
618 |
slog (L_DEBUG, _("%s: %s."), (const char *)si, strerror (errno)); |
619 |
} |
620 |
|
621 |
delete pkt; |
622 |
} |
623 |
else |
624 |
{ |
625 |
slog (L_ERR, |
626 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
627 |
revents); |
628 |
exit (EXIT_FAILURE); |
629 |
} |
630 |
} |
631 |
#endif |
632 |
|
633 |
inline void |
634 |
vpn::udpv4_ev (ev::io &w, int revents) |
635 |
{ |
636 |
if (revents & EV_READ) |
637 |
{ |
638 |
vpn_packet *pkt = new vpn_packet; |
639 |
struct sockaddr_in sa; |
640 |
socklen_t sa_len = sizeof (sa); |
641 |
int len; |
642 |
|
643 |
len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
644 |
|
645 |
sockinfo si(sa, PROT_UDPv4); |
646 |
|
647 |
if (len > 0) |
648 |
{ |
649 |
pkt->len = len; |
650 |
|
651 |
recv_vpn_packet (pkt, si); |
652 |
} |
653 |
else |
654 |
{ |
655 |
// probably ECONNRESET or somesuch |
656 |
slog (L_DEBUG, _("%s: fd %d, %s."), (const char *)si, w.fd, strerror (errno)); |
657 |
} |
658 |
|
659 |
delete pkt; |
660 |
} |
661 |
else |
662 |
{ |
663 |
slog (L_ERR, |
664 |
_("FATAL: unknown revents %08x in socket, exiting.\n"), |
665 |
revents); |
666 |
exit (EXIT_FAILURE); |
667 |
} |
668 |
} |
669 |
|
670 |
inline void |
671 |
vpn::tap_ev (ev::io &w, int revents) |
672 |
{ |
673 |
if (revents & EV_READ) |
674 |
{ |
675 |
/* process data */ |
676 |
tap_packet *pkt; |
677 |
|
678 |
pkt = tap->recv (); |
679 |
|
680 |
if (!pkt) |
681 |
return; |
682 |
|
683 |
if (pkt->len > 14) |
684 |
{ |
685 |
int dst = mac2id (pkt->dst); |
686 |
int src = mac2id (pkt->src); |
687 |
|
688 |
if (src != THISNODE->id) |
689 |
{ |
690 |
slog (L_ERR, _("FATAL: tap packet not originating on current node received (if-up script not working properly?), exiting.")); |
691 |
exit (EXIT_FAILURE); |
692 |
} |
693 |
|
694 |
if (dst == THISNODE->id) |
695 |
{ |
696 |
slog (L_ERR, _("FATAL: tap packet destined for current node received, exiting.")); |
697 |
exit (EXIT_FAILURE); |
698 |
} |
699 |
|
700 |
if (dst > conns.size ()) |
701 |
slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
702 |
else |
703 |
inject_data_packet (pkt, dst); |
704 |
} |
705 |
|
706 |
delete pkt; |
707 |
} |
708 |
else |
709 |
abort (); |
710 |
} |
711 |
|
712 |
inline void |
713 |
vpn::event_cb (ev::timer &w, int) |
714 |
{ |
715 |
if (events) |
716 |
{ |
717 |
if (events & EVENT_SHUTDOWN) |
718 |
{ |
719 |
slog (L_INFO, _("preparing shutdown...")); |
720 |
|
721 |
shutdown_all (); |
722 |
remove_pid (conf.pidfilename); |
723 |
slog (L_INFO, _("exiting.")); |
724 |
exit (EXIT_SUCCESS); |
725 |
} |
726 |
|
727 |
if (events & EVENT_RECONNECT) |
728 |
{ |
729 |
slog (L_INFO, _("forced reconnect.")); |
730 |
|
731 |
reconnect_all (); |
732 |
} |
733 |
|
734 |
events = 0; |
735 |
} |
736 |
} |
737 |
|
738 |
void |
739 |
vpn::shutdown_all () |
740 |
{ |
741 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
742 |
(*c)->shutdown (); |
743 |
} |
744 |
|
745 |
void |
746 |
vpn::reconnect_all () |
747 |
{ |
748 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
749 |
delete *c; |
750 |
|
751 |
conns.clear (); |
752 |
|
753 |
connection_init (); |
754 |
|
755 |
for (configuration::node_vector::iterator i = conf.nodes.begin (); i != conf.nodes.end (); ++i) |
756 |
conns.push_back (new connection (this, *i)); |
757 |
|
758 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
759 |
(*c)->establish_connection (); |
760 |
} |
761 |
|
762 |
bool vpn::can_direct (conf_node *src, conf_node *dst) const |
763 |
{ |
764 |
return src != dst |
765 |
&& src->may_direct (dst) |
766 |
&& dst->may_direct (src) |
767 |
&& (((src->protocols & dst->protocols) && src->connectmode == conf_node::C_ALWAYS) |
768 |
|| (src->protocols & dst->connectable_protocols ())); |
769 |
} |
770 |
|
771 |
// only works for indirect and routed connections: find a router |
772 |
// from THISNODE to dst |
773 |
connection *vpn::find_router_for (const connection *dst) |
774 |
{ |
775 |
connection *router = 0; |
776 |
|
777 |
// first try to find a router with a direct connection, route there |
778 |
// regardless of any other considerations. |
779 |
{ |
780 |
u32 prio = 1; |
781 |
|
782 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
783 |
{ |
784 |
connection *c = *i; |
785 |
|
786 |
if (c->conf->routerprio > prio |
787 |
&& c->conf != THISNODE |
788 |
&& can_direct (c->conf, dst->conf) |
789 |
&& c->ictx && c->octx) |
790 |
{ |
791 |
prio = c->conf->routerprio; |
792 |
router = c; |
793 |
} |
794 |
} |
795 |
} |
796 |
|
797 |
if (router) |
798 |
return router; |
799 |
|
800 |
// second try find the router with the highest priority, higher than ours |
801 |
{ |
802 |
u32 prio = THISNODE->routerprio ? THISNODE->routerprio : 1; |
803 |
|
804 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
805 |
{ |
806 |
connection *c = *i; |
807 |
|
808 |
if (c->conf->routerprio > prio |
809 |
&& c != dst |
810 |
&& c->conf != THISNODE |
811 |
&& c->ictx && c->octx) |
812 |
{ |
813 |
prio = c->conf->routerprio; |
814 |
router = c; |
815 |
} |
816 |
} |
817 |
} |
818 |
|
819 |
return router; |
820 |
} |
821 |
|
822 |
void vpn::connection_established (connection *c) |
823 |
{ |
824 |
for (conns_vector::iterator i = conns.begin (); i != conns.end (); ++i) |
825 |
{ |
826 |
connection *o = *i; |
827 |
|
828 |
if (!o->is_direct |
829 |
&& o->si.valid () |
830 |
&& c->si != o->si |
831 |
&& c == find_router_for (o)) |
832 |
{ |
833 |
slog (L_DEBUG, _("%s: can now route packets via %s, re-keying connection."), |
834 |
o->conf->nodename, c->conf->nodename); |
835 |
o->rekey (); |
836 |
} |
837 |
} |
838 |
} |
839 |
|
840 |
void vpn::send_connect_request (connection *c) |
841 |
{ |
842 |
connection *r = find_router_for (c); |
843 |
|
844 |
if (r) |
845 |
{ |
846 |
slog (L_TRACE, _("%s: no address known, sending mediated connection request via %s."), |
847 |
c->conf->nodename, r->conf->nodename); |
848 |
r->send_connect_request (c->conf->id); |
849 |
} |
850 |
else |
851 |
slog (L_DEBUG, _("%s: no way to connect and no router found: unable to connect at this time."), |
852 |
c->conf->nodename); |
853 |
} |
854 |
|
855 |
void |
856 |
connection::dump_status () |
857 |
{ |
858 |
slog (L_NOTICE, _("node %s (id %d)"), conf->nodename, conf->id); |
859 |
slog (L_NOTICE, _(" connectmode %d (%d) / sockaddr %s / minor %d"), |
860 |
connectmode, conf->connectmode, (const char *)si, (int)prot_minor); |
861 |
slog (L_NOTICE, _(" ictx/octx %08lx/%08lx / oseqno %d / retry_cnt %d"), |
862 |
(long)ictx, (long)octx, (int)oseqno, (int)retry_cnt); |
863 |
} |
864 |
|
865 |
void |
866 |
vpn::dump_status () |
867 |
{ |
868 |
slog (L_NOTICE, _("BEGIN status dump (%ld)"), (long)ev_now ()); |
869 |
|
870 |
for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
871 |
(*c)->dump_status (); |
872 |
|
873 |
slog (L_NOTICE, _("END status dump")); |
874 |
} |
875 |
|
876 |
vpn::vpn (void) |
877 |
{ |
878 |
event .set<vpn, &vpn::event_cb > (this); |
879 |
udpv4_ev_watcher .set<vpn, &vpn::udpv4_ev > (this); |
880 |
ipv4_ev_watcher .set<vpn, &vpn::ipv4_ev > (this); |
881 |
#if ENABLE_TCP |
882 |
tcpv4_ev_watcher .set<vpn, &vpn::tcpv4_ev > (this); |
883 |
#endif |
884 |
#if ENABLE_ICMP |
885 |
icmpv4_ev_watcher.set<vpn, &vpn::icmpv4_ev> (this); |
886 |
#endif |
887 |
#if ENABLE_DNS |
888 |
dnsv4_ev_watcher .set<vpn, &vpn::dnsv4_ev > (this); |
889 |
#endif |
890 |
tap_ev_watcher .set<vpn, &vpn::tap_ev > (this); |
891 |
} |
892 |
|
893 |
vpn::~vpn () |
894 |
{ |
895 |
} |
896 |
|