1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/*
* anytun
*
* The secure anycast tunneling protocol (satp) defines a protocol used
* for communication between any combination of unicast and anycast
* tunnel endpoints. It has less protocol overhead than IPSec in Tunnel
* mode and allows tunneling of every ETHER TYPE protocol (e.g.
* ethernet, ip, arp ...). satp directly includes cryptography and
* message authentication based on the methodes used by SRTP. It is
* intended to deliver a generic, scaleable and secure solution for
* tunneling and relaying of packets of any protocol.
*
*
* Copyright (C) 2007-2008 Othmar Gsenger, Erwin Nindl,
* Christian Pointner <satp@wirdorange.org>
*
* This file is part of Anytun.
*
* Anytun is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 3 as
* published by the Free Software Foundation.
*
* Anytun is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with anytun. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdexcept>
#include <iostream>
#include <string>
#include <cstdio>
#include <cstring>
#include "endian.h"
#include "cipher.h"
#include "log.h"
void Cipher::encrypt(KeyDerivation& kd, PlainPacket & in, EncryptedPacket & out, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
u_int32_t len = cipher(kd, in, in.getLength(), out.getPayload(), out.getPayloadLength(), seq_nr, sender_id, mux);
out.setSenderId(sender_id);
out.setSeqNr(seq_nr);
out.setMux(mux);
out.setPayloadLength(len);
}
void Cipher::decrypt(KeyDerivation& kd, EncryptedPacket & in, PlainPacket & out)
{
u_int32_t len = decipher(kd, in.getPayload() , in.getPayloadLength(), out, out.getLength(), in.getSeqNr(), in.getSenderId(), in.getMux());
out.setLength(len);
}
//******* NullCipher *******
u_int32_t NullCipher::cipher(KeyDerivation& kd, u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
std::memcpy(out, in, (ilen < olen) ? ilen : olen);
return (ilen < olen) ? ilen : olen;
}
u_int32_t NullCipher::decipher(KeyDerivation& kd, u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
std::memcpy(out, in, (ilen < olen) ? ilen : olen);
return (ilen < olen) ? ilen : olen;
}
#ifndef NOCRYPT
//****** AesIcmCipher ******
AesIcmCipher::AesIcmCipher(kd_dir_t d) : Cipher(d), key_(u_int32_t(DEFAULT_KEY_LENGTH/8)), salt_(u_int32_t(SALT_LENGTH))
{
init();
}
AesIcmCipher::AesIcmCipher(kd_dir_t d, u_int16_t key_length) : Cipher(d), key_(u_int32_t(key_length/8)), salt_(u_int32_t(SALT_LENGTH))
{
init(key_length);
}
void AesIcmCipher::init(u_int16_t key_length)
{
#ifndef USE_SSL_CRYPTO
handle_ = NULL;
int algo;
switch(key_length) {
case 128: algo = GCRY_CIPHER_AES128; break;
case 192: algo = GCRY_CIPHER_AES192; break;
case 256: algo = GCRY_CIPHER_AES256; break;
default: {
cLog.msg(Log::PRIO_CRIT) << "AesIcmCipher::AesIcmCipher: cipher key length of " << key_length << " Bits is not supported";
return;
}
}
gcry_error_t err = gcry_cipher_open(&handle_, algo, GCRY_CIPHER_MODE_CTR, 0);
if( err ) {
cLog.msg(Log::PRIO_CRIT) << "AesIcmCipher::AesIcmCipher: Failed to open cipher" << LogGpgError(err);
}
#endif
}
AesIcmCipher::~AesIcmCipher()
{
#ifndef USE_SSL_CRYPTO
if(handle_)
gcry_cipher_close(handle_);
#endif
}
u_int32_t AesIcmCipher::cipher(KeyDerivation& kd, u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
calc(kd, in, ilen, out, olen, seq_nr, sender_id, mux);
return (ilen < olen) ? ilen : olen;
}
u_int32_t AesIcmCipher::decipher(KeyDerivation& kd, u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
calc(kd, in, ilen, out, olen, seq_nr, sender_id, mux);
return (ilen < olen) ? ilen : olen;
}
void AesIcmCipher::calcCtr(KeyDerivation& kd, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
kd.generate(dir_, LABEL_SATP_SALT, seq_nr, salt_);
#ifdef ANYTUN_02_COMPAT
if(!salt_[int32_t(0)])
salt_[int32_t(0)] = 1;
#endif
std::memcpy(ctr_.salt_.buf_, salt_.getBuf(), SALT_LENGTH);
ctr_.salt_.zero_ = 0;
ctr_.params_.mux_ ^= MUX_T_HTON(mux);
ctr_.params_.sender_id_ ^= SENDER_ID_T_HTON(sender_id);
ctr_.params_.seq_nr_ ^= SEQ_NR_T_HTON(seq_nr);
return;
}
void AesIcmCipher::calc(KeyDerivation& kd, u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
#ifndef USE_SSL_CRYPTO
if(!handle_)
return;
#endif
kd.generate(dir_, LABEL_SATP_ENCRYPTION, seq_nr, key_);
#ifdef USE_SSL_CRYPTO
int ret = AES_set_encrypt_key(key_.getBuf(), key_.getLength()*8, &aes_key_);
if(ret) {
cLog.msg(Log::PRIO_ERR) << "AesIcmCipher: Failed to set cipher ssl key (code: " << ret << ")";
return;
}
#else
gcry_error_t err = gcry_cipher_setkey(handle_, key_.getBuf(), key_.getLength());
if(err) {
cLog.msg(Log::PRIO_ERR) << "AesIcmCipher: Failed to set cipher key: " << LogGpgError(err);
return;
}
#endif
calcCtr(kd, seq_nr, sender_id, mux);
#ifndef USE_SSL_CRYPTO
err = gcry_cipher_setctr(handle_, ctr_.buf_, CTR_LENGTH);
if(err) {
cLog.msg(Log::PRIO_ERR) << "AesIcmCipher: Failed to set cipher CTR: " << LogGpgError(err);
return;
}
err = gcry_cipher_encrypt(handle_, out, olen, in, ilen);
if(err) {
cLog.msg(Log::PRIO_ERR) << "AesIcmCipher: Failed to de/encrypt packet: " << LogGpgError(err);
return;
}
#else
if(CTR_LENGTH != AES_BLOCK_SIZE) {
cLog.msg(Log::PRIO_ERR) << "AesIcmCipher: Failed to set cipher CTR: size don't fits";
return;
}
u_int32_t num = 0;
std::memset(ecount_buf_, 0, AES_BLOCK_SIZE);
AES_ctr128_encrypt(in, out, (ilen < olen) ? ilen : olen, &aes_key_, ctr_.buf_, ecount_buf_, &num);
#endif
}
#endif
|
