1 | /* |
1 | /* |
2 | vpn.C -- handle the protocol, encryption, handshaking etc. |
2 | vpn.C -- handle the protocol, encryption, handshaking etc. |
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3 | Copyright (C) 2003 Marc Lehmann <pcg@goof.com> |
3 | |
4 | |
4 | This program is free software; you can redistribute it and/or modify |
5 | This program is free software; you can redistribute it and/or modify |
5 | it under the terms of the GNU General Public License as published by |
6 | it under the terms of the GNU General Public License as published by |
6 | the Free Software Foundation; either version 2 of the License, or |
7 | the Free Software Foundation; either version 2 of the License, or |
7 | (at your option) any later version. |
8 | (at your option) any later version. |
… | |
… | |
24 | #include <cstring> |
25 | #include <cstring> |
25 | #include <cstdio> |
26 | #include <cstdio> |
26 | |
27 | |
27 | #include <sys/types.h> |
28 | #include <sys/types.h> |
28 | #include <sys/socket.h> |
29 | #include <sys/socket.h> |
29 | #include <sys/poll.h> |
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30 | #include <sys/wait.h> |
30 | #include <sys/wait.h> |
31 | #include <errno.h> |
31 | #include <errno.h> |
32 | #include <time.h> |
32 | #include <time.h> |
33 | #include <unistd.h> |
33 | #include <unistd.h> |
34 | #include <fcntl.h> |
34 | #include <fcntl.h> |
35 | #include <arpa/inet.h> |
35 | #include <sys/socket.h> |
36 | #include <netinet/in.h> |
36 | |
37 | #include <netinet/ip_icmp.h> |
37 | #include "netcompat.h" |
38 | |
38 | |
39 | #include "pidfile.h" |
39 | #include "pidfile.h" |
40 | |
40 | |
41 | #include "connection.h" |
41 | #include "connection.h" |
42 | #include "util.h" |
42 | #include "util.h" |
43 | #include "vpn.h" |
43 | #include "vpn.h" |
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44 | |
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45 | vpn network; // THE vpn (bad design...) |
44 | |
46 | |
45 | ///////////////////////////////////////////////////////////////////////////// |
47 | ///////////////////////////////////////////////////////////////////////////// |
46 | |
48 | |
47 | const char *vpn::script_if_up () |
49 | const char *vpn::script_if_up () |
48 | { |
50 | { |
… | |
… | |
52 | mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
54 | mtu += ETH_OVERHEAD - 6 - 6; // now we have the data portion |
53 | mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round |
55 | mtu -= mtu % EVP_CIPHER_block_size (CIPHER); // round |
54 | mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
56 | mtu -= ETH_OVERHEAD - 6 - 6; // and get interface mtu again |
55 | |
57 | |
56 | char *env; |
58 | char *env; |
57 | asprintf (&env, "CONFBASE=%s", confbase); |
59 | asprintf (&env, "CONFBASE=%s", confbase); putenv (env); |
58 | putenv (env); |
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59 | asprintf (&env, "NODENAME=%s", THISNODE->nodename); |
60 | asprintf (&env, "NODENAME=%s", THISNODE->nodename); putenv (env); |
60 | putenv (env); |
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61 | asprintf (&env, "NODEID=%d", THISNODE->id); |
61 | asprintf (&env, "NODEID=%d", THISNODE->id); putenv (env); |
62 | putenv (env); |
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63 | asprintf (&env, "IFNAME=%s", tap->interface ()); |
62 | asprintf (&env, "IFNAME=%s", tap->interface ()); putenv (env); |
64 | putenv (env); |
63 | asprintf (&env, "IFTYPE=%s", IFTYPE); putenv (env); |
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64 | asprintf (&env, "IFSUBTYPE=%s", IFSUBTYPE); putenv (env); |
65 | asprintf (&env, "MTU=%d", mtu); |
65 | asprintf (&env, "MTU=%d", mtu); putenv (env); |
66 | putenv (env); |
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67 | asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x", |
66 | asprintf (&env, "MAC=%02x:%02x:%02x:%02x:%02x:%02x", |
68 | 0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8, |
67 | 0xfe, 0xfd, 0x80, 0x00, THISNODE->id >> 8, |
69 | THISNODE->id & 0xff); |
68 | THISNODE->id & 0xff); |
70 | putenv (env); |
69 | putenv (env); |
71 | |
70 | |
… | |
… | |
84 | if (ipv4_fd < 0) |
83 | if (ipv4_fd < 0) |
85 | return -1; |
84 | return -1; |
86 | |
85 | |
87 | fcntl (ipv4_fd, F_SETFL, O_NONBLOCK); |
86 | fcntl (ipv4_fd, F_SETFL, O_NONBLOCK); |
88 | |
87 | |
89 | #ifdef IP_MTU_DISCOVER |
88 | #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
90 | // this I really consider a linux bug. I am neither connected |
89 | // this I really consider a linux bug. I am neither connected |
91 | // nor do I fragment myself. Linux still sets DF and doesn't |
90 | // nor do I fragment myself. Linux still sets DF and doesn't |
92 | // fragment for me sometimes. |
91 | // fragment for me sometimes. |
93 | { |
92 | { |
94 | int oval = IP_PMTUDISC_DONT; |
93 | int oval = IP_PMTUDISC_DONT; |
… | |
… | |
122 | { |
121 | { |
123 | int oval = 1; |
122 | int oval = 1; |
124 | setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
123 | setsockopt (udpv4_fd, SOL_SOCKET, SO_REUSEADDR, &oval, sizeof oval); |
125 | } |
124 | } |
126 | |
125 | |
127 | #ifdef IP_MTU_DISCOVER |
126 | #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
128 | // this I really consider a linux bug. I am neither connected |
127 | // this I really consider a linux bug. I am neither connected |
129 | // nor do I fragment myself. Linux still sets DF and doesn't |
128 | // nor do I fragment myself. Linux still sets DF and doesn't |
130 | // fragment for me sometimes. |
129 | // fragment for me sometimes. |
131 | { |
130 | { |
132 | int oval = IP_PMTUDISC_DONT; |
131 | int oval = IP_PMTUDISC_DONT; |
… | |
… | |
166 | |
165 | |
167 | setsockopt (icmpv4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval); |
166 | setsockopt (icmpv4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval); |
168 | } |
167 | } |
169 | #endif |
168 | #endif |
170 | |
169 | |
171 | #ifdef IP_MTU_DISCOVER |
170 | #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) |
172 | // this I really consider a linux bug. I am neither connected |
171 | // this I really consider a linux bug. I am neither connected |
173 | // nor do I fragment myself. Linux still sets DF and doesn't |
172 | // nor do I fragment myself. Linux still sets DF and doesn't |
174 | // fragment for me sometimes. |
173 | // fragment for me sometimes. |
175 | { |
174 | { |
176 | int oval = IP_PMTUDISC_DONT; |
175 | int oval = IP_PMTUDISC_DONT; |
… | |
… | |
271 | } |
270 | } |
272 | |
271 | |
273 | bool |
272 | bool |
274 | vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
273 | vpn::send_ipv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
275 | { |
274 | { |
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275 | #if defined(SOL_IP) && defined(IP_TOS) |
276 | setsockopt (ipv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
276 | setsockopt (ipv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
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277 | #endif |
277 | sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
278 | sendto (ipv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
278 | |
279 | |
279 | return true; |
280 | return true; |
280 | } |
281 | } |
281 | |
282 | |
… | |
… | |
304 | |
305 | |
305 | #if ENABLE_ICMP |
306 | #if ENABLE_ICMP |
306 | bool |
307 | bool |
307 | vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
308 | vpn::send_icmpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
308 | { |
309 | { |
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310 | #if defined(SOL_IP) && defined(IP_TOS) |
309 | setsockopt (icmpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
311 | setsockopt (icmpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
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312 | #endif |
310 | |
313 | |
311 | pkt->unshift_hdr (4); |
314 | pkt->unshift_hdr (4); |
312 | |
315 | |
313 | icmphdr *hdr = (icmphdr *)&((*pkt)[0]); |
316 | icmp_header *hdr = (icmp_header *)&((*pkt)[0]); |
314 | hdr->type = ::conf.icmp_type; |
317 | hdr->type = ::conf.icmp_type; |
315 | hdr->code = 255; |
318 | hdr->code = 255; |
316 | hdr->checksum = 0; |
319 | hdr->checksum = 0; |
317 | hdr->checksum = ipv4_checksum ((u16 *)hdr, pkt->len); |
320 | hdr->checksum = ipv4_checksum ((u16 *)hdr, pkt->len); |
318 | |
321 | |
… | |
… | |
323 | #endif |
326 | #endif |
324 | |
327 | |
325 | bool |
328 | bool |
326 | vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
329 | vpn::send_udpv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
327 | { |
330 | { |
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331 | #if defined(SOL_IP) && defined(IP_TOS) |
328 | setsockopt (udpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
332 | setsockopt (udpv4_fd, SOL_IP, IP_TOS, &tos, sizeof tos); |
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333 | #endif |
329 | sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
334 | sendto (udpv4_fd, &((*pkt)[0]), pkt->len, 0, si.sav4 (), si.salenv4 ()); |
330 | |
335 | |
331 | return true; |
336 | return true; |
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337 | } |
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338 | |
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339 | void |
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340 | vpn::inject_data_packet (tap_packet *pkt, int dst) |
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341 | { |
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342 | if (dst) |
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343 | { |
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344 | // unicast |
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345 | if (dst != THISNODE->id) |
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346 | conns[dst - 1]->inject_data_packet (pkt); |
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347 | } |
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348 | else |
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349 | { |
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350 | // broadcast, this is ugly, but due to the security policy |
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351 | // we have to connect to all hosts... |
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352 | for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
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353 | if ((*c)->conf != THISNODE) |
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354 | (*c)->inject_data_packet (pkt, true); |
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355 | } |
332 | } |
356 | } |
333 | |
357 | |
334 | void |
358 | void |
335 | vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
359 | vpn::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) |
336 | { |
360 | { |
… | |
… | |
353 | connection *c = conns[src - 1]; |
377 | connection *c = conns[src - 1]; |
354 | |
378 | |
355 | if (dst == 0) |
379 | if (dst == 0) |
356 | slog (L_WARN, _("%s(%s): received broadcast (protocol violation)"), |
380 | slog (L_WARN, _("%s(%s): received broadcast (protocol violation)"), |
357 | c->conf->nodename, (const char *)rsi); |
381 | c->conf->nodename, (const char *)rsi); |
358 | else if (dst != 0 && dst != THISNODE->id) |
382 | else if (dst != THISNODE->id) |
359 | { |
383 | { |
360 | if (THISNODE->routerprio) |
384 | if (THISNODE->routerprio) |
361 | // the tos setting gets lost here. who cares. |
385 | // the tos setting gets lost here. who cares. |
362 | conns[dst - 1]->inject_vpn_packet (pkt); |
386 | conns[dst - 1]->inject_vpn_packet (pkt); |
363 | else |
387 | else |
… | |
… | |
435 | |
459 | |
436 | if (len > 0) |
460 | if (len > 0) |
437 | { |
461 | { |
438 | pkt->len = len; |
462 | pkt->len = len; |
439 | |
463 | |
440 | icmphdr *hdr = (icmphdr *)&((*pkt)[IP_OVERHEAD]); |
464 | icmp_header *hdr = (icmp_header *)&((*pkt)[IP_OVERHEAD]); |
441 | |
465 | |
442 | if (hdr->type == ::conf.icmp_type |
466 | if (hdr->type == ::conf.icmp_type |
443 | && hdr->code == 255) |
467 | && hdr->code == 255) |
444 | { |
468 | { |
445 | // raw sockets deliver the ipv4, but don't expect it on sends |
469 | // raw sockets deliver the ipv4, but don't expect it on sends |
… | |
… | |
524 | /* process data */ |
548 | /* process data */ |
525 | tap_packet *pkt; |
549 | tap_packet *pkt; |
526 | |
550 | |
527 | pkt = tap->recv (); |
551 | pkt = tap->recv (); |
528 | |
552 | |
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553 | if (!pkt) |
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554 | return; |
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555 | |
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556 | if (pkt->len > 14) |
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557 | { |
529 | int dst = mac2id (pkt->dst); |
558 | int dst = mac2id (pkt->dst); |
530 | int src = mac2id (pkt->src); |
559 | int src = mac2id (pkt->src); |
531 | |
560 | |
532 | if (src != THISNODE->id) |
561 | if (src != THISNODE->id) |
533 | { |
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534 | slog (L_ERR, _("FATAL: tap packet not originating on current node received, terminating.")); |
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535 | exit (1); |
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536 | } |
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537 | |
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538 | if (dst == THISNODE->id) |
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539 | { |
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540 | slog (L_ERR, _("FATAL: tap packet destined for current node received, terminating.")); |
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541 | exit (1); |
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542 | } |
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543 | |
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544 | if (dst > conns.size ()) |
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545 | slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
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546 | else |
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547 | { |
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548 | if (dst) |
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549 | { |
562 | { |
550 | // unicast |
563 | slog (L_ERR, _("FATAL: tap packet not originating on current node received, exiting.")); |
551 | if (dst != THISNODE->id) |
564 | exit (1); |
552 | conns[dst - 1]->inject_data_packet (pkt); |
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553 | } |
565 | } |
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566 | |
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567 | if (dst == THISNODE->id) |
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568 | { |
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569 | slog (L_ERR, _("FATAL: tap packet destined for current node received, exiting.")); |
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570 | exit (1); |
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571 | } |
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572 | |
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573 | if (dst > conns.size ()) |
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574 | slog (L_ERR, _("tap packet for unknown node %d received, ignoring."), dst); |
554 | else |
575 | else |
555 | { |
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556 | // broadcast, this is ugly, but due to the security policy |
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557 | // we have to connect to all hosts... |
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558 | for (conns_vector::iterator c = conns.begin (); c != conns.end (); ++c) |
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559 | if ((*c)->conf != THISNODE) |
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560 | (*c)->inject_data_packet (pkt); |
576 | inject_data_packet (pkt, dst); |
561 | } |
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562 | } |
577 | } |
563 | |
578 | |
564 | delete pkt; |
579 | delete pkt; |
565 | } |
580 | } |
566 | else if (revents & (POLLHUP | POLLERR)) |
581 | else if (revents & (POLLHUP | POLLERR)) |