comparison NaCl/crypto_core/salsa20.cs @ 20:c873e3dd73fe

Added NaCl cryptography code
author Ivo Smits <Ivo@UCIS.nl>
date Mon, 15 Apr 2013 00:43:48 +0200
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19:b9ef273964fd 20:c873e3dd73fe
1 using System;
2
3 namespace UCIS.NaCl.crypto_core {
4 static unsafe class salsa20 {
5 static Boolean UseNativeFunctions = false;
6 static unsafe internal Boolean EnableNativeImplementation() {
7 UseNativeFunctions = false;
8 Byte* dummy = stackalloc Byte[64];
9 try {
10 if (Native.crypto_core_salsa20(dummy, dummy, dummy, dummy) != 0) return false;
11 } catch (Exception) {
12 return false;
13 }
14 return UseNativeFunctions = true;
15 }
16
17 public const int OUTPUTBYTES = 64;
18 public const int INPUTBYTES = 16;
19 public const int KEYBYTES = 32;
20 public const int CONSTBYTES = 16;
21
22 public const int ROUNDS = 20;
23
24 static UInt32 load_littleendian(Byte* x) {
25 return (UInt32)(x[0] | (x[1] << 8) | (x[2] << 16) | (x[3] << 24));
26 }
27
28 static void store_littleendian(Byte* x, UInt32 u) {
29 x[0] = (Byte)u; u >>= 8;
30 x[1] = (Byte)u; u >>= 8;
31 x[2] = (Byte)u; u >>= 8;
32 x[3] = (Byte)u;
33 }
34
35 public static void crypto_core(Byte* outv, Byte* inv, Byte* k, Byte[] c) {
36 fixed (Byte* cp = c) crypto_core(outv, inv, k, cp);
37 }
38
39 public static void crypto_core(Byte* outv, Byte* inv, Byte* k, Byte* c) {
40 if (UseNativeFunctions) {
41 Native.crypto_core_salsa20(outv, inv, k, c);
42 return;
43 }
44
45 UInt32 x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15;
46 UInt32 j0, j1, j2, j3, j4, j5, j6, j7, j8, j9, j10, j11, j12, j13, j14, j15;
47
48 j0 = x0 = load_littleendian(c + 0);
49 j1 = x1 = load_littleendian(k + 0);
50 j2 = x2 = load_littleendian(k + 4);
51 j3 = x3 = load_littleendian(k + 8);
52 j4 = x4 = load_littleendian(k + 12);
53 j5 = x5 = load_littleendian(c + 4);
54 j6 = x6 = load_littleendian(inv + 0);
55 j7 = x7 = load_littleendian(inv + 4);
56 j8 = x8 = load_littleendian(inv + 8);
57 j9 = x9 = load_littleendian(inv + 12);
58 j10 = x10 = load_littleendian(c + 8);
59 j11 = x11 = load_littleendian(k + 16);
60 j12 = x12 = load_littleendian(k + 20);
61 j13 = x13 = load_littleendian(k + 24);
62 j14 = x14 = load_littleendian(k + 28);
63 j15 = x15 = load_littleendian(c + 12);
64
65 for (int i = ROUNDS; i > 0; i -= 2) {
66 UInt32 tsum;
67 tsum = x0 + x12; x4 ^= (tsum << 7) | (tsum >> (32 - 7));
68 tsum = x4 + x0; x8 ^= (tsum << 9) | (tsum >> (32 - 9));
69 tsum = x8 + x4; x12 ^= (tsum << 13) | (tsum >> (32 - 13));
70 tsum = x12 + x8; x0 ^= (tsum << 18) | (tsum >> (32 - 18));
71 tsum = x5 + x1; x9 ^= (tsum << 7) | (tsum >> (32 - 7));
72 tsum = x9 + x5; x13 ^= (tsum << 9) | (tsum >> (32 - 9));
73 tsum = x13 + x9; x1 ^= (tsum << 13) | (tsum >> (32 - 13));
74 tsum = x1 + x13; x5 ^= (tsum << 18) | (tsum >> (32 - 18));
75 tsum = x10 + x6; x14 ^= (tsum << 7) | (tsum >> (32 - 7));
76 tsum = x14 + x10; x2 ^= (tsum << 9) | (tsum >> (32 - 9));
77 tsum = x2 + x14; x6 ^= (tsum << 13) | (tsum >> (32 - 13));
78 tsum = x6 + x2; x10 ^= (tsum << 18) | (tsum >> (32 - 18));
79 tsum = x15 + x11; x3 ^= (tsum << 7) | (tsum >> (32 - 7));
80 tsum = x3 + x15; x7 ^= (tsum << 9) | (tsum >> (32 - 9));
81 tsum = x7 + x3; x11 ^= (tsum << 13) | (tsum >> (32 - 13));
82 tsum = x11 + x7; x15 ^= (tsum << 18) | (tsum >> (32 - 18));
83 tsum = x0 + x3; x1 ^= (tsum << 7) | (tsum >> (32 - 7));
84 tsum = x1 + x0; x2 ^= (tsum << 9) | (tsum >> (32 - 9));
85 tsum = x2 + x1; x3 ^= (tsum << 13) | (tsum >> (32 - 13));
86 tsum = x3 + x2; x0 ^= (tsum << 18) | (tsum >> (32 - 18));
87 tsum = x5 + x4; x6 ^= (tsum << 7) | (tsum >> (32 - 7));
88 tsum = x6 + x5; x7 ^= (tsum << 9) | (tsum >> (32 - 9));
89 tsum = x7 + x6; x4 ^= (tsum << 13) | (tsum >> (32 - 13));
90 tsum = x4 + x7; x5 ^= (tsum << 18) | (tsum >> (32 - 18));
91 tsum = x10 + x9; x11 ^= (tsum << 7) | (tsum >> (32 - 7));
92 tsum = x11 + x10; x8 ^= (tsum << 9) | (tsum >> (32 - 9));
93 tsum = x8 + x11; x9 ^= (tsum << 13) | (tsum >> (32 - 13));
94 tsum = x9 + x8; x10 ^= (tsum << 18) | (tsum >> (32 - 18));
95 tsum = x15 + x14; x12 ^= (tsum << 7) | (tsum >> (32 - 7));
96 tsum = x12 + x15; x13 ^= (tsum << 9) | (tsum >> (32 - 9));
97 tsum = x13 + x12; x14 ^= (tsum << 13) | (tsum >> (32 - 13));
98 tsum = x14 + x13; x15 ^= (tsum << 18) | (tsum >> (32 - 18));
99 }
100
101 x0 += j0;
102 x1 += j1;
103 x2 += j2;
104 x3 += j3;
105 x4 += j4;
106 x5 += j5;
107 x6 += j6;
108 x7 += j7;
109 x8 += j8;
110 x9 += j9;
111 x10 += j10;
112 x11 += j11;
113 x12 += j12;
114 x13 += j13;
115 x14 += j14;
116 x15 += j15;
117
118 store_littleendian(outv + 0, x0);
119 store_littleendian(outv + 4, x1);
120 store_littleendian(outv + 8, x2);
121 store_littleendian(outv + 12, x3);
122 store_littleendian(outv + 16, x4);
123 store_littleendian(outv + 20, x5);
124 store_littleendian(outv + 24, x6);
125 store_littleendian(outv + 28, x7);
126 store_littleendian(outv + 32, x8);
127 store_littleendian(outv + 36, x9);
128 store_littleendian(outv + 40, x10);
129 store_littleendian(outv + 44, x11);
130 store_littleendian(outv + 48, x12);
131 store_littleendian(outv + 52, x13);
132 store_littleendian(outv + 56, x14);
133 store_littleendian(outv + 60, x15);
134 }
135 }
136 }