Security Scol plugin
shark.cpp
1// shark.cpp - originally written and placed in the public domain by Wei Dai
2
3#include "pch.h"
4#include "shark.h"
5#include "misc.h"
6#include "modes.h"
7#include "gf256.h"
8
9#if CRYPTOPP_GCC_DIAGNOSTIC_AVAILABLE
10# pragma GCC diagnostic ignored "-Wmissing-braces"
11#endif
12
13NAMESPACE_BEGIN(CryptoPP)
14
15static word64 SHARKTransform(word64 a)
16{
17 static const byte iG[8][8] = {
18 0xe7, 0x30, 0x90, 0x85, 0xd0, 0x4b, 0x91, 0x41,
19 0x53, 0x95, 0x9b, 0xa5, 0x96, 0xbc, 0xa1, 0x68,
20 0x02, 0x45, 0xf7, 0x65, 0x5c, 0x1f, 0xb6, 0x52,
21 0xa2, 0xca, 0x22, 0x94, 0x44, 0x63, 0x2a, 0xa2,
22 0xfc, 0x67, 0x8e, 0x10, 0x29, 0x75, 0x85, 0x71,
23 0x24, 0x45, 0xa2, 0xcf, 0x2f, 0x22, 0xc1, 0x0e,
24 0xa1, 0xf1, 0x71, 0x40, 0x91, 0x27, 0x18, 0xa5,
25 0x56, 0xf4, 0xaf, 0x32, 0xd2, 0xa4, 0xdc, 0x71,
26 };
27
28 word64 result=0;
29 GF256 gf256(0xf5);
30 for (unsigned int i=0; i<8; i++)
31 for(unsigned int j=0; j<8; j++)
32 result ^= word64(gf256.Multiply(iG[i][j], GF256::Element(a>>(56-8*j)))) << (56-8*i);
33 return result;
34}
35
36void SHARK::Base::UncheckedSetKey(const byte *key, unsigned int keyLen, const NameValuePairs &params)
37{
38 AssertValidKeyLength(keyLen);
39
40 m_rounds = GetRoundsAndThrowIfInvalid(params, this);
41 m_roundKeys.New(m_rounds+1);
42
43 // concatenate key enough times to fill a
44 for (unsigned int i=0; i<(m_rounds+1)*8; i++)
45 ((byte *)m_roundKeys.begin())[i] = key[i%keyLen];
46
48 e.InitForKeySetup();
49 byte IV[8] = {0,0,0,0,0,0,0,0};
51
52 cfb.ProcessString((byte *)m_roundKeys.begin(), (m_rounds+1)*8);
53
54 ConditionalByteReverse(BIG_ENDIAN_ORDER, m_roundKeys.begin(), m_roundKeys.begin(), (m_rounds+1)*8);
55
56 m_roundKeys[m_rounds] = SHARKTransform(m_roundKeys[m_rounds]);
57
58 if (!IsForwardTransformation())
59 {
60 unsigned int i;
61
62 // transform encryption round keys into decryption round keys
63 for (i=0; i<m_rounds/2; i++)
64 std::swap(m_roundKeys[i], m_roundKeys[m_rounds-i]);
65
66 for (i=1; i<m_rounds; i++)
67 m_roundKeys[i] = SHARKTransform(m_roundKeys[i]);
68 }
69
70#if (CRYPTOPP_LITTLE_ENDIAN)
71 m_roundKeys[0] = ByteReverse(m_roundKeys[0]);
72 m_roundKeys[m_rounds] = ByteReverse(m_roundKeys[m_rounds]);
73#endif
74}
75
76// construct an SHARK_Enc object with fixed round keys, to be used to initialize actual round keys
77void SHARK::Enc::InitForKeySetup()
78{
79 m_rounds = DEFAULT_ROUNDS;
80 m_roundKeys.New(DEFAULT_ROUNDS+1);
81
82 for (unsigned int i=0; i<DEFAULT_ROUNDS; i++)
83 m_roundKeys[i] = cbox[0][i];
84
85 m_roundKeys[DEFAULT_ROUNDS] = SHARKTransform(cbox[0][DEFAULT_ROUNDS]);
86
87#if (CRYPTOPP_LITTLE_ENDIAN)
88 m_roundKeys[0] = ByteReverse(m_roundKeys[0]);
89 m_roundKeys[m_rounds] = ByteReverse(m_roundKeys[m_rounds]);
90#endif
91}
92
93void SHARK::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
94{
95 CRYPTOPP_ASSERT(IsAlignedOn(inBlock,GetAlignmentOf<word64>()));
96 word64 tmp = *(word64 *)(void *)inBlock ^ m_roundKeys[0];
97
99 tmp = cbox[0][GetByte(order, tmp, 0)] ^ cbox[1][GetByte(order, tmp, 1)]
100 ^ cbox[2][GetByte(order, tmp, 2)] ^ cbox[3][GetByte(order, tmp, 3)]
101 ^ cbox[4][GetByte(order, tmp, 4)] ^ cbox[5][GetByte(order, tmp, 5)]
102 ^ cbox[6][GetByte(order, tmp, 6)] ^ cbox[7][GetByte(order, tmp, 7)]
103 ^ m_roundKeys[1];
104
105 for(unsigned int i=2; i<m_rounds; i++)
106 {
107 tmp = cbox[0][GETBYTE(tmp, 7)] ^ cbox[1][GETBYTE(tmp, 6)]
108 ^ cbox[2][GETBYTE(tmp, 5)] ^ cbox[3][GETBYTE(tmp, 4)]
109 ^ cbox[4][GETBYTE(tmp, 3)] ^ cbox[5][GETBYTE(tmp, 2)]
110 ^ cbox[6][GETBYTE(tmp, 1)] ^ cbox[7][GETBYTE(tmp, 0)]
111 ^ m_roundKeys[i];
112 }
113
114 PutBlock<byte, BigEndian>(xorBlock, outBlock)
115 (sbox[GETBYTE(tmp, 7)])
116 (sbox[GETBYTE(tmp, 6)])
117 (sbox[GETBYTE(tmp, 5)])
118 (sbox[GETBYTE(tmp, 4)])
119 (sbox[GETBYTE(tmp, 3)])
120 (sbox[GETBYTE(tmp, 2)])
121 (sbox[GETBYTE(tmp, 1)])
122 (sbox[GETBYTE(tmp, 0)]);
123
124 CRYPTOPP_ASSERT(IsAlignedOn(outBlock,GetAlignmentOf<word64>()));
125 *(word64 *)(void *)outBlock ^= m_roundKeys[m_rounds];
126}
127
128void SHARK::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
129{
130 CRYPTOPP_ASSERT(IsAlignedOn(inBlock,GetAlignmentOf<word64>()));
131 word64 tmp = *(word64 *)(void *)inBlock ^ m_roundKeys[0];
132
134 tmp = cbox[0][GetByte(order, tmp, 0)] ^ cbox[1][GetByte(order, tmp, 1)]
135 ^ cbox[2][GetByte(order, tmp, 2)] ^ cbox[3][GetByte(order, tmp, 3)]
136 ^ cbox[4][GetByte(order, tmp, 4)] ^ cbox[5][GetByte(order, tmp, 5)]
137 ^ cbox[6][GetByte(order, tmp, 6)] ^ cbox[7][GetByte(order, tmp, 7)]
138 ^ m_roundKeys[1];
139
140 for(unsigned int i=2; i<m_rounds; i++)
141 {
142 tmp = cbox[0][GETBYTE(tmp, 7)] ^ cbox[1][GETBYTE(tmp, 6)]
143 ^ cbox[2][GETBYTE(tmp, 5)] ^ cbox[3][GETBYTE(tmp, 4)]
144 ^ cbox[4][GETBYTE(tmp, 3)] ^ cbox[5][GETBYTE(tmp, 2)]
145 ^ cbox[6][GETBYTE(tmp, 1)] ^ cbox[7][GETBYTE(tmp, 0)]
146 ^ m_roundKeys[i];
147 }
148
149 PutBlock<byte, BigEndian>(xorBlock, outBlock)
150 (sbox[GETBYTE(tmp, 7)])
151 (sbox[GETBYTE(tmp, 6)])
152 (sbox[GETBYTE(tmp, 5)])
153 (sbox[GETBYTE(tmp, 4)])
154 (sbox[GETBYTE(tmp, 3)])
155 (sbox[GETBYTE(tmp, 2)])
156 (sbox[GETBYTE(tmp, 1)])
157 (sbox[GETBYTE(tmp, 0)]);
158
159 CRYPTOPP_ASSERT(IsAlignedOn(outBlock,GetAlignmentOf<word64>()));
160 *(word64 *)(void *)outBlock ^= m_roundKeys[m_rounds];
161}
162
163NAMESPACE_END
GF(256) with polynomial basis.
Definition gf256.h:16
Interface for retrieving values given their names.
Definition cryptlib.h:322
Access a block of memory.
Definition misc.h:2807
ByteOrder
Provides the byte ordering.
Definition cryptlib.h:143
@ BIG_ENDIAN_ORDER
byte order is big-endian
Definition cryptlib.h:147
Classes and functions for schemes over GF(256)
Utility functions for the Crypto++ library.
byte ByteReverse(byte value)
Reverses bytes in a 8-bit value.
Definition misc.h:2022
bool IsAlignedOn(const void *ptr, unsigned int alignment)
Determines whether ptr is aligned to a minimum value.
Definition misc.h:1227
T ConditionalByteReverse(ByteOrder order, T value)
Reverses bytes in a value depending upon endianness.
Definition misc.h:2208
unsigned int GetByte(ByteOrder order, T value, unsigned int index)
Gets a byte from a value.
Definition misc.h:2010
ByteOrder GetNativeByteOrder()
Returns NativeByteOrder as an enumerated ByteOrder value.
Definition misc.h:1264
Classes for block cipher modes of operation.
Precompiled header file.
Classes for the SHARK block cipher.