1 | /* |
1 | /* |
2 | vpn_dns.C -- handle the dns tunnel part of the protocol. |
2 | vpn_dns.C -- handle the dns tunnel part of the protocol. |
3 | Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de> |
3 | Copyright (C) 2003-2008 Marc Lehmann <gvpe@schmorp.de> |
4 | |
4 | |
5 | This file is part of GVPE. |
5 | This file is part of GVPE. |
6 | |
6 | |
7 | GVPE is free software; you can redistribute it and/or modify |
7 | GVPE is free software; you can redistribute it and/or modify it |
8 | 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 |
9 | the Free Software Foundation; either version 2 of the License, or |
9 | Free Software Foundation; either version 3 of the License, or (at your |
10 | (at your option) any later version. |
10 | option) any later version. |
11 | |
11 | |
12 | 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 |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General |
15 | GNU General Public License for more details. |
15 | Public License for more details. |
16 | |
16 | |
17 | 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 |
18 | along with gvpe; if not, write to the Free Software |
18 | with this program; if not, see <http://www.gnu.org/licenses/>. |
19 | Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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. |
20 | */ |
30 | */ |
21 | |
31 | |
22 | // TODO: EDNS0 option to increase dns mtu? |
32 | // TODO: EDNS0 option to increase dns mtu? |
23 | // TODO: re-write dns packet parsing/creation using a safe mem-buffer |
33 | // TODO: re-write dns packet parsing/creation using a safe mem-buffer |
24 | // to ensure no buffer overflows or similar problems. |
34 | // to ensure no buffer overflows or similar problems. |
… | |
… | |
42 | #include <unistd.h> |
52 | #include <unistd.h> |
43 | #include <fcntl.h> |
53 | #include <fcntl.h> |
44 | |
54 | |
45 | #include <map> |
55 | #include <map> |
46 | |
56 | |
|
|
57 | #include <cstdio> /* bug in libgmp: gmp.h relies on cstdio being included */ |
47 | #include <gmp.h> |
58 | #include <gmp.h> |
48 | |
59 | |
49 | #include "netcompat.h" |
60 | #include "netcompat.h" |
50 | |
61 | |
51 | #include "vpn.h" |
62 | #include "vpn.h" |
… | |
… | |
72 | #define MAX_PKT_SIZE 512 |
83 | #define MAX_PKT_SIZE 512 |
73 | |
84 | |
74 | #define RR_TYPE_A 1 |
85 | #define RR_TYPE_A 1 |
75 | #define RR_TYPE_NULL 10 |
86 | #define RR_TYPE_NULL 10 |
76 | #define RR_TYPE_TXT 16 |
87 | #define RR_TYPE_TXT 16 |
|
|
88 | #define RR_TYPE_AAAA 28 |
77 | #define RR_TYPE_ANY 255 |
89 | #define RR_TYPE_ANY 255 |
78 | |
90 | |
79 | #define RR_CLASS_IN 1 |
91 | #define RR_CLASS_IN 1 |
80 | |
92 | |
81 | #define CMD_IP_1 207 |
93 | #define CMD_IP_1 207 |
… | |
… | |
559 | vector<dns_rcv *> rcvpq; |
571 | vector<dns_rcv *> rcvpq; |
560 | |
572 | |
561 | byte_stream rcvdq; int rcvseq; int repseq; |
573 | byte_stream rcvdq; int rcvseq; int repseq; |
562 | byte_stream snddq; int sndseq; |
574 | byte_stream snddq; int sndseq; |
563 | |
575 | |
564 | void time_cb (ev::timer &w, int revents); ev::timer tw; |
576 | inline void time_cb (ev::timer &w, int revents); ev::timer tw; |
565 | void receive_rep (dns_rcv *r); |
577 | void receive_rep (dns_rcv *r); |
566 | |
578 | |
567 | dns_connection (connection *c); |
579 | dns_connection (connection *c); |
568 | ~dns_connection (); |
580 | ~dns_connection (); |
569 | }; |
581 | }; |
… | |
… | |
724 | |
736 | |
725 | dns_connection::dns_connection (connection *c) |
737 | dns_connection::dns_connection (connection *c) |
726 | : c (c) |
738 | : c (c) |
727 | , rcvdq (MAX_BACKLOG * 2) |
739 | , rcvdq (MAX_BACKLOG * 2) |
728 | , snddq (MAX_BACKLOG) |
740 | , snddq (MAX_BACKLOG) |
729 | , tw (this, &dns_connection::time_cb) |
|
|
730 | { |
741 | { |
|
|
742 | tw.set<dns_connection, &dns_connection::time_cb> (this); |
|
|
743 | |
731 | vpn = c->vpn; |
744 | vpn = c->vpn; |
732 | |
745 | |
733 | established = false; |
746 | established = false; |
734 | |
747 | |
735 | rcvseq = repseq = sndseq = 0; |
748 | rcvseq = repseq = sndseq = 0; |