Botan: src/block/xtea_simd/xtea_simd.cpp Source File

Botan 1.10.12

- Main Page
- Related Pages
- Namespaces
- Classes
- Files

- File List
- File Members

xtea_simd.cpp
Go to the documentation of this file.
1 /*
2 * XTEA in SIMD
3 * (C) 2009 Jack Lloyd
4 *
5 * Distributed under the terms of the Botan license
6 */
7
8 #include <botan/xtea_simd.h>
9 #include <botan/loadstor.h>
10 #include <botan/internal/simd_32.h>
11
12 namespace Botan {
13
14 namespace {
15
16 void xtea_encrypt_8(const byte in[64], byte out[64], const u32bit EK[64])
17 {
18 SIMD_32 L0 = SIMD_32::load_be(in );
19 SIMD_32 R0 = SIMD_32::load_be(in + 16);
20 SIMD_32 L1 = SIMD_32::load_be(in + 32);
21 SIMD_32 R1 = SIMD_32::load_be(in + 48);
22
23 SIMD_32::transpose(L0, R0, L1, R1);
24
25 for(size_t i = 0; i != 32; i += 2)
26 {
27 SIMD_32 K0(EK[2*i ]);
28 SIMD_32 K1(EK[2*i+1]);
29 SIMD_32 K2(EK[2*i+2]);
30 SIMD_32 K3(EK[2*i+3]);
31
32 L0 += (((R0 << 4) ^ (R0 >> 5)) + R0) ^ K0;
33 L1 += (((R1 << 4) ^ (R1 >> 5)) + R1) ^ K0;
34
35 R0 += (((L0 << 4) ^ (L0 >> 5)) + L0) ^ K1;
36 R1 += (((L1 << 4) ^ (L1 >> 5)) + L1) ^ K1;
37
38 L0 += (((R0 << 4) ^ (R0 >> 5)) + R0) ^ K2;
39 L1 += (((R1 << 4) ^ (R1 >> 5)) + R1) ^ K2;
40
41 R0 += (((L0 << 4) ^ (L0 >> 5)) + L0) ^ K3;
42 R1 += (((L1 << 4) ^ (L1 >> 5)) + L1) ^ K3;
43 }
44
45 SIMD_32::transpose(L0, R0, L1, R1);
46
47 L0.store_be(out);
48 R0.store_be(out + 16);
49 L1.store_be(out + 32);
50 R1.store_be(out + 48);
51 }
52
53 void xtea_decrypt_8(const byte in[64], byte out[64], const u32bit EK[64])
54 {
55 SIMD_32 L0 = SIMD_32::load_be(in );
56 SIMD_32 R0 = SIMD_32::load_be(in + 16);
57 SIMD_32 L1 = SIMD_32::load_be(in + 32);
58 SIMD_32 R1 = SIMD_32::load_be(in + 48);
59
60 SIMD_32::transpose(L0, R0, L1, R1);
61
62 for(size_t i = 0; i != 32; i += 2)
63 {
64 SIMD_32 K0(EK[63 - 2*i]);
65 SIMD_32 K1(EK[62 - 2*i]);
66 SIMD_32 K2(EK[61 - 2*i]);
67 SIMD_32 K3(EK[60 - 2*i]);
68
69 R0 -= (((L0 << 4) ^ (L0 >> 5)) + L0) ^ K0;
70 R1 -= (((L1 << 4) ^ (L1 >> 5)) + L1) ^ K0;
71
72 L0 -= (((R0 << 4) ^ (R0 >> 5)) + R0) ^ K1;
73 L1 -= (((R1 << 4) ^ (R1 >> 5)) + R1) ^ K1;
74
75 R0 -= (((L0 << 4) ^ (L0 >> 5)) + L0) ^ K2;
76 R1 -= (((L1 << 4) ^ (L1 >> 5)) + L1) ^ K2;
77
78 L0 -= (((R0 << 4) ^ (R0 >> 5)) + R0) ^ K3;
79 L1 -= (((R1 << 4) ^ (R1 >> 5)) + R1) ^ K3;
80 }
81
82 SIMD_32::transpose(L0, R0, L1, R1);
83
84 L0.store_be(out);
85 R0.store_be(out + 16);
86 L1.store_be(out + 32);
87 R1.store_be(out + 48);
88 }
89
90 }
91
92 /*
93 * XTEA Encryption
94 */
95 void XTEA_SIMD::encrypt_n(const byte in[], byte out[], size_t blocks) const
96 {
97 const u32bit* KS = &(this->get_EK()[0]);
98
99 while(blocks >= 8)
100 {
101 xtea_encrypt_8(in, out, KS);
102 in += 8 * BLOCK_SIZE;
103 out += 8 * BLOCK_SIZE;
104 blocks -= 8;
105 }
106
107 if(blocks)
108 XTEA::encrypt_n(in, out, blocks);
109 }
110
111 /*
112 * XTEA Decryption
113 */
114 void XTEA_SIMD::decrypt_n(const byte in[], byte out[], size_t blocks) const
115 {
116 const u32bit* KS = &(this->get_EK()[0]);
117
118 while(blocks >= 8)
119 {
120 xtea_decrypt_8(in, out, KS);
121 in += 8 * BLOCK_SIZE;
122 out += 8 * BLOCK_SIZE;
123 blocks -= 8;
124 }
125
126 if(blocks)
127 XTEA::decrypt_n(in, out, blocks);
128 }
129
130 }
Botan::XTEA::encrypt_n
void encrypt_n(const byte in[], byte out[], size_t blocks) const
Definition: xtea.cpp:62
Botan::load_be
T load_be(const byte in[], size_t off)
Definition: loadstor.h:100
Botan::Block_Cipher_Fixed_Params< 8, 16 >::BLOCK_SIZE
Definition: block_cipher.h:107
Botan::XTEA_SIMD::decrypt_n
void decrypt_n(const byte in[], byte out[], size_t blocks) const
Definition: xtea_simd.cpp:114
R0
#define R0
Definition: asm_x86_64.h:51
Botan::byte
unsigned char byte
Definition: types.h:22
Botan::XTEA::decrypt_n
void decrypt_n(const byte in[], byte out[], size_t blocks) const
Definition: xtea.cpp:93
Botan
Definition: algo_base.h:14
R1
#define R1
Definition: asm_x86_64.h:52
Botan::XTEA_SIMD::encrypt_n
void encrypt_n(const byte in[], byte out[], size_t blocks) const
Definition: xtea_simd.cpp:95
Botan::u32bit
unsigned int u32bit
Definition: types.h:32
Botan::XTEA::get_EK
const SecureVector< u32bit > & get_EK() const
Definition: xtea.h:33