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
195
196
197
198
199
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
*/
#include "oox/crypto/AgileEngine.hxx"
#include <oox/helper/binaryinputstream.hxx>
#include <oox/helper/binaryoutputstream.hxx>
namespace oox {
namespace core {
namespace {
const sal_uInt32 constSegmentLength = 4096;
bool hashCalc(std::vector<sal_uInt8>& output,
std::vector<sal_uInt8>& input,
const OUString& sAlgorithm )
{
if (sAlgorithm == "SHA1")
return Digest::sha1(output, input);
else if (sAlgorithm == "SHA512")
return Digest::sha512(output, input);
return false;
}
} // namespace
Crypto::CryptoType AgileEngine::cryptoType(const AgileEncryptionInfo& rInfo)
{
if (rInfo.keyBits == 128 && rInfo.cipherAlgorithm == "AES" && rInfo.cipherChaining == "ChainingModeCBC")
return Crypto::AES_128_CBC;
else if (rInfo.keyBits == 256 && rInfo.cipherAlgorithm == "AES" && rInfo.cipherChaining == "ChainingModeCBC")
return Crypto::AES_256_CBC;
return Crypto::UNKNOWN;
}
void AgileEngine::calculateBlock(
std::vector<sal_uInt8> const & rBlock,
std::vector<sal_uInt8>& rHashFinal,
std::vector<sal_uInt8>& rInput,
std::vector<sal_uInt8>& rOutput)
{
std::vector<sal_uInt8> hash(mInfo.hashSize, 0);
std::vector<sal_uInt8> dataFinal(mInfo.hashSize + rBlock.size(), 0);
std::copy(rHashFinal.begin(), rHashFinal.end(), dataFinal.begin());
std::copy(rBlock.begin(), rBlock.end(), dataFinal.begin() + mInfo.hashSize);
hashCalc(hash, dataFinal, mInfo.hashAlgorithm);
sal_Int32 keySize = mInfo.keyBits / 8;
std::vector<sal_uInt8> key(keySize, 0);
std::copy(hash.begin(), hash.begin() + keySize, key.begin());
Decrypt aDecryptor(key, mInfo.saltValue, cryptoType(mInfo));
aDecryptor.update(rOutput, rInput);
}
void AgileEngine::calculateHashFinal(const OUString& rPassword, std::vector<sal_uInt8>& aHashFinal)
{
sal_Int32 saltSize = mInfo.saltSize;
std::vector<sal_uInt8>& salt = mInfo.saltValue;
sal_uInt32 passwordByteLength = rPassword.getLength() * 2;
std::vector<sal_uInt8> initialData(saltSize + passwordByteLength);
std::copy(salt.begin(), salt.end(), initialData.begin());
const sal_uInt8* passwordByteArray = reinterpret_cast<const sal_uInt8*>(rPassword.getStr());
std::copy(
passwordByteArray,
passwordByteArray + passwordByteLength,
initialData.begin() + saltSize);
std::vector<sal_uInt8> hash(mInfo.hashSize, 0);
hashCalc(hash, initialData, mInfo.hashAlgorithm);
std::vector<sal_uInt8> data(mInfo.hashSize + 4, 0);
for (sal_Int32 i = 0; i < mInfo.spinCount; i++)
{
ByteOrderConverter::writeLittleEndian(data.data(), i);
std::copy(hash.begin(), hash.end(), data.begin() + 4);
hashCalc(hash, data, mInfo.hashAlgorithm);
}
std::copy(hash.begin(), hash.end(), aHashFinal.begin());
}
bool AgileEngine::generateEncryptionKey(const OUString& rPassword)
{
static const std::vector<sal_uInt8> constBlock1{ 0xfe, 0xa7, 0xd2, 0x76, 0x3b, 0x4b, 0x9e, 0x79 };
static const std::vector<sal_uInt8> constBlock2{ 0xd7, 0xaa, 0x0f, 0x6d, 0x30, 0x61, 0x34, 0x4e };
static const std::vector<sal_uInt8> constBlock3{ 0x14, 0x6e, 0x0b, 0xe7, 0xab, 0xac, 0xd0, 0xd6 };
mKey.clear();
mKey.resize(mInfo.keyBits / 8, 0);
std::vector<sal_uInt8> hashFinal(mInfo.hashSize, 0);
calculateHashFinal(rPassword, hashFinal);
std::vector<sal_uInt8>& encryptedHashInput = mInfo.encryptedVerifierHashInput;
std::vector<sal_uInt8> hashInput(mInfo.saltSize, 0);
calculateBlock(constBlock1, hashFinal, encryptedHashInput, hashInput);
std::vector<sal_uInt8>& encryptedHashValue = mInfo.encryptedVerifierHashValue;
std::vector<sal_uInt8> hashValue(encryptedHashValue.size(), 0);
calculateBlock(constBlock2, hashFinal, encryptedHashValue, hashValue);
std::vector<sal_uInt8> hash(mInfo.hashSize, 0);
hashCalc(hash, hashInput, mInfo.hashAlgorithm);
if (std::equal (hash.begin(), hash.end(), hashValue.begin()) )
{
std::vector<sal_uInt8>& encryptedKeyValue = mInfo.encryptedKeyValue;
calculateBlock(constBlock3, hashFinal, encryptedKeyValue, mKey);
return true;
}
return false;
}
bool AgileEngine::decrypt(BinaryXInputStream& aInputStream,
BinaryXOutputStream& aOutputStream)
{
sal_uInt32 totalSize = aInputStream.readuInt32(); // Document unencrypted size - 4 bytes
aInputStream.skip(4); // Reserved 4 Bytes
std::vector<sal_uInt8>& keyDataSalt = mInfo.keyDataSalt;
sal_uInt32 saltSize = mInfo.saltSize;
sal_uInt32 keySize = mInfo.keyBits / 8;
sal_uInt32 segment = 0;
std::vector<sal_uInt8> saltWithBlockKey(saltSize + sizeof(segment), 0);
std::copy(keyDataSalt.begin(), keyDataSalt.end(), saltWithBlockKey.begin());
std::vector<sal_uInt8> hash(mInfo.hashSize, 0);
std::vector<sal_uInt8> iv(keySize, 0);
std::vector<sal_uInt8> inputBuffer(constSegmentLength);
std::vector<sal_uInt8> outputBuffer(constSegmentLength);
sal_uInt32 inputLength;
sal_uInt32 outputLength;
sal_uInt32 remaining = totalSize;
while ((inputLength = aInputStream.readMemory(inputBuffer.data(), constSegmentLength)) > 0)
{
sal_uInt8* segmentBegin = reinterpret_cast<sal_uInt8*>(&segment);
sal_uInt8* segmentEnd = segmentBegin + sizeof(segment);
std::copy(segmentBegin, segmentEnd, saltWithBlockKey.begin() + saltSize);
hashCalc(hash, saltWithBlockKey, mInfo.hashAlgorithm);
// Only if hash > keySize
std::copy(hash.begin(), hash.begin() + keySize, iv.begin());
Decrypt aDecryptor(mKey, iv, AgileEngine::cryptoType(mInfo));
outputLength = aDecryptor.update(outputBuffer, inputBuffer, inputLength);
sal_uInt32 writeLength = outputLength > remaining ? remaining : outputLength;
aOutputStream.writeMemory(outputBuffer.data(), writeLength);
remaining -= outputLength;
segment++;
}
return true;
}
void AgileEngine::writeEncryptionInfo(
const OUString& /*aPassword*/,
BinaryXOutputStream& /*rStream*/)
{
// Agile encrypting is not supported for now
}
void AgileEngine::encrypt(
BinaryXInputStream& /*aInputStream*/,
BinaryXOutputStream& /*aOutputStream*/)
{
// Agile encrypting is not supported for now
}
} // namespace core
} // namespace oox
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|
