Botan: src/hash/md2/md2.cpp Source File

Botan 1.10.16

md2.cpp
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1 /*
2 * MD2
3 * (C) 1999-2007 Jack Lloyd
4 *
5 * Distributed under the terms of the Botan license
6 */
7
8 #include <botan/md2.h>
9 #include <botan/internal/xor_buf.h>
10
11 namespace Botan {
12
13 /**
14 * MD2 Compression Function
15 */
16 void MD2::hash(const byte input[])
17 {
18 static const byte SBOX[256] = {
19 0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36, 0x54, 0xA1,
20 0xEC, 0xF0, 0x06, 0x13, 0x62, 0xA7, 0x05, 0xF3, 0xC0, 0xC7, 0x73, 0x8C,
21 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C, 0x82, 0xCA, 0x1E, 0x9B, 0x57, 0x3C,
22 0xFD, 0xD4, 0xE0, 0x16, 0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12,
23 0xBE, 0x4E, 0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E,
24 0xBB, 0x2F, 0xEE, 0x7A, 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2, 0x07, 0x3F,
25 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21, 0x80, 0x7F, 0x5D, 0x9A,
26 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E, 0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03,
27 0xFF, 0x19, 0x30, 0xB3, 0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A,
28 0xAC, 0x56, 0xAA, 0xC6, 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6,
29 0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1, 0x45, 0x9D, 0x70, 0x59,
30 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65, 0xE6, 0x2D, 0xA8, 0x02,
31 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0, 0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69,
32 0x34, 0x40, 0x7E, 0x0F, 0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A,
33 0xC3, 0x5C, 0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26, 0x2C, 0x53, 0x0D, 0x6E,
34 0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81, 0x4D, 0x52,
35 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA, 0x24, 0xE1, 0x7B, 0x08,
36 0x0C, 0xBD, 0xB1, 0x4A, 0x78, 0x88, 0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D,
37 0xE9, 0xCB, 0xD5, 0xFE, 0x3B, 0x00, 0x1D, 0x39, 0xF2, 0xEF, 0xB7, 0x0E,
38 0x66, 0x58, 0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
39 0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99, 0x8D, 0x33,
40 0x9F, 0x11, 0x83, 0x14 };
41
42 X.copy(16, input, hash_block_size());
43 xor_buf(&X[32], &X[0], &X[16], hash_block_size());
44 byte T = 0;
45
46 for(size_t i = 0; i != 18; ++i)
47 {
48 for(size_t k = 0; k != 48; k += 8)
49 {
50 T = X[k ] ^= SBOX[T]; T = X[k+1] ^= SBOX[T];
51 T = X[k+2] ^= SBOX[T]; T = X[k+3] ^= SBOX[T];
52 T = X[k+4] ^= SBOX[T]; T = X[k+5] ^= SBOX[T];
53 T = X[k+6] ^= SBOX[T]; T = X[k+7] ^= SBOX[T];
54 }
55
56 T += static_cast<byte>(i);
57 }
58
59 T = checksum[15];
60 for(size_t i = 0; i != hash_block_size(); ++i)
61 T = checksum[i] ^= SBOX[input[i] ^ T];
62 }
63
64 /**
65 * Update the hash
66 */
67 void MD2::add_data(const byte input[], size_t length)
68 {
69 buffer.copy(position, input, length);
70
71 if(position + length >= hash_block_size())
72 {
73 hash(&buffer[0]);
74 input += (hash_block_size() - position);
75 length -= (hash_block_size() - position);
76 while(length >= hash_block_size())
77 {
78 hash(input);
79 input += hash_block_size();
80 length -= hash_block_size();
81 }
82 buffer.copy(input, length);
83 position = 0;
84 }
85 position += length;
86 }
87
88 /**
89 * Finalize a MD2 Hash
90 */
91 void MD2::final_result(byte output[])
92 {
93 for(size_t i = position; i != hash_block_size(); ++i)
94 buffer[i] = static_cast<byte>(hash_block_size() - position);
95
96 hash(&buffer[0]);
97 hash(&checksum[0]);
98 copy_mem(output, &X[0], output_length());
99 clear();
100 }
101
102 /**
103 * Clear memory of sensitive data
104 */
105 void MD2::clear()
106 {
107 zeroise(X);
108 zeroise(checksum);
109 zeroise(buffer);
110 position = 0;
111 }
112
113 }
Botan::MD2::hash_block_size
size_t hash_block_size() const
Definition: md2.h:23
Botan::MemoryRegion::copy
void copy(const T in[], size_t n)
Definition: secmem.h:120
Botan::byte
unsigned char byte
Definition: types.h:22
Botan::MD2::clear
void clear()
Definition: md2.cpp:105
Botan::MD2::output_length
size_t output_length() const
Definition: md2.h:22
Botan::copy_mem
void copy_mem(T *out, const T *in, size_t n)
Definition: mem_ops.h:22
Botan
Definition: algo_base.h:14
Botan::xor_buf
void xor_buf(byte out[], const byte in[], size_t length)
Definition: xor_buf.h:21
Botan::zeroise
void zeroise(MemoryRegion< T > &vec)
Definition: secmem.h:415