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/cvs/gvpe/src/device.h
Revision: 1.26
Committed: Wed Jul 17 16:40:57 2013 UTC (10 years, 11 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.25: +3 -0 lines
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File Contents

# Content
1 /*
2 device.h -- generic header for device.c
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 #ifndef GVPE_DEVICE_H__
33 #define GVPE_DEVICE_H__
34
35 #include "config.h"
36
37 #define IFNAMESIZE 256 // be conservative
38
39 #include "global.h"
40 #include "util.h"
41
42 struct net_packet
43 {
44 u32 len; // actually u16, but padding...
45 // upto 4 bytes at the end might get overwritten when decrypting,
46 // which means len, above, is regularly overwritten with part
47 // of the random prefix when RAND_BYTES=12.
48
49 u8 &operator[] (u16 offset) const;
50 u8 *at (u16 offset) const;
51
52 void unshift_hdr (u16 hdrsize)
53 {
54 memmove ((void *)&(*this)[hdrsize], (void *)&(*this)[0], len);
55 len += hdrsize;
56 }
57
58 void skip_hdr (u16 hdrsize)
59 {
60 len -= hdrsize;
61 memmove ((void *)&(*this)[0], (void *)&(*this)[hdrsize], len);
62 }
63
64 u16 ipv4_hdr_len () const
65 {
66 return ((*this)[0] & 15) << 2;
67 }
68
69 void set (const net_packet &pkt)
70 {
71 len = pkt.len;
72 memcpy (&((*this)[0]), &(pkt[0]), len);
73 }
74
75 bool is_ipv4 () const
76 {
77 return (*this)[12] == 0x08 && (*this)[13] == 0x00 // IP
78 && ((*this)[14] & 0xf0) == 0x40; // IPv4
79 }
80
81 u32 &ipv4_src () const
82 {
83 return *(u32 *)&(*this)[26];
84 }
85
86 u32 &ipv4_dst () const
87 {
88 return *(u32 *)&(*this)[30];
89 }
90
91 bool is_arp () const
92 {
93 return (*this)[12] == 0x08 && (*this)[13] == 0x06 // 0806 protocol
94 && (*this)[14] == 0x00 && (*this)[15] == 0x01 // 0001 hw_format
95 && (*this)[16] == 0x08 && (*this)[17] == 0x00 // 0800 prot_format
96 && (*this)[18] == 0x06 && (*this)[19] == 0x04; // 06 hw_len 04 prot_len
97 }
98
99 void *operator new (size_t s);
100 void operator delete (void *p);
101 };
102
103 struct data_packet : net_packet
104 {
105 u8 data_[MAXSIZE];
106 };
107
108 inline
109 u8 &net_packet::operator[] (u16 offset) const
110 {
111 return ((data_packet *)this)->data_[offset];
112 }
113
114 inline
115 u8 *net_packet::at (u16 offset) const
116 {
117 return &((*this)[offset]);
118 }
119
120 struct tap_packet : net_packet
121 {
122 mac dst;
123 mac src;
124 u8 data[MAXSIZE - 12];
125 };
126
127 struct tap_device
128 {
129 int fd;
130
131 // network interface name or identifier
132 char ifrname[IFNAMESIZE + 1];
133
134 char *device;
135
136 tap_device ();
137 ~tap_device ();
138
139 //bool open ();
140 //void close ();
141
142 const char *interface () { return ifrname; }
143 const char *info ();
144 const char *if_up ();
145
146 tap_packet *recv ();
147 void send (tap_packet *pkt);
148 };
149
150 //extern tap_device *tap_device ();
151
152 #endif
153