annotate NaCl/crypto_sign/edwards25519sha512batch.cs @ 68:e811297f5aa4

Updated USBLib: removed old LibUsbDotNet compatibility code and added new information helper classes
author Ivo Smits <Ivo@UCIS.nl>
date Wed, 16 Oct 2013 16:58:39 +0200
parents c873e3dd73fe
children 7e9d1cfcc562
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1 ???using System;
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2 using UCIS.NaCl;
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3 using System.Runtime.InteropServices;
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4
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5 namespace UCIS.NaCl.crypto_sign {
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6 public static class edwards25519sha512batch {
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7 public const int SECRETKEYBYTES = 64;
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8 public const int PUBLICKEYBYTES = 32;
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9 public const int CRYPTO_BYTES = 64;
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10
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11 /*Arithmetic modulo the group order n = 2^252 + 27742317777372353535851937790883648493 = 7237005577332262213973186563042994240857116359379907606001950938285454250989 */
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12
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13 unsafe struct sc25519 {
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14 public fixed UInt32 v[32]; //crypto_uint32 v[32];
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15
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16 static UInt32[] m = new UInt32[32] {0xED, 0xD3, 0xF5, 0x5C, 0x1A, 0x63, 0x12, 0x58, 0xD6, 0x9C, 0xF7, 0xA2, 0xDE, 0xF9, 0xDE, 0x14,
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17 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10};
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18
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19 static UInt32[] mu = new UInt32[33] {0x1B, 0x13, 0x2C, 0x0A, 0xA3, 0xE5, 0x9C, 0xED, 0xA7, 0x29, 0x63, 0x08, 0x5D, 0x21, 0x06, 0x21,
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20 0xEB, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x0F};
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21
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22 /* Reduce coefficients of r before calling reduce_add_sub */
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23 static unsafe void reduce_add_sub(sc25519* r) {
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24 int i, b = 0, pb = 0, nb;
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25 Byte* t = stackalloc Byte[32];
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26
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27 for (i = 0; i < 32; i++) {
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28 b = (r->v[i] < pb + m[i]) ? 1 : 0;
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29 t[i] = (Byte)(r->v[i] - pb - m[i] + b * 256);
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30 pb = b;
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31 }
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32 nb = 1 - b;
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33 for (i = 0; i < 32; i++) r->v[i] = (uint)(r->v[i] * b + t[i] * nb);
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34 }
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35
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36 /* Reduce coefficients of x before calling barrett_reduce */
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37 static unsafe void barrett_reduce(sc25519* r, UInt32* x) { // const crypto_uint32 x[64]
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38 /* See HAC, Alg. 14.42 */
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39 UInt32* q2 = stackalloc UInt32[66]; // { 0 };
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40 for (int z = 0; z < 66; z++) q2[z] = 0;
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41 UInt32* q3 = q2 + 33;
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42 UInt32* r1 = stackalloc UInt32[33];
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43 UInt32* r2 = stackalloc UInt32[33]; // { 0 };
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44 for (int z = 0; z < 33; z++) r2[z] = 0;
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45 UInt32 carry;
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46 int b, pb = 0;
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47
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48 for (int i = 0; i < 33; i++)
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49 for (int j = 0; j < 33; j++)
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50 if (i + j >= 31) q2[i + j] += mu[i] * x[j + 31];
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51 carry = q2[31] >> 8;
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52 q2[32] += carry;
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53 carry = q2[32] >> 8;
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54 q2[33] += carry;
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55
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56 for (int i = 0; i < 33; i++) r1[i] = x[i];
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57 for (int i = 0; i < 32; i++)
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58 for (int j = 0; j < 33; j++)
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59 if (i + j < 33) r2[i + j] += m[i] * q3[j];
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60
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61 for (int i = 0; i < 32; i++) {
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62 carry = r2[i] >> 8;
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63 r2[i + 1] += carry;
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64 r2[i] &= 0xff;
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65 }
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66
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67 for (int i = 0; i < 32; i++) {
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68 b = (r1[i] < pb + r2[i]) ? 1 : 0;
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69 r->v[i] = (uint)(r1[i] - pb - r2[i] + b * 256);
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70 pb = b;
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71 }
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72
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73 /* XXX: Can it really happen that r<0?, See HAC, Alg 14.42, Step 3
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74 * If so: Handle it here!
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75 */
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76
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77 reduce_add_sub(r);
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78 reduce_add_sub(r);
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79 }
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80
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81 /*
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82 static int iszero(const sc25519 *x)
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83 {
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84 // Implement
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85 return 0;
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86 }
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87 */
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88
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89 public static unsafe void sc25519_from32bytes(sc25519* r, Byte* x) { //const unsigned char x[32]
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90 UInt32* t = stackalloc UInt32[64]; // { 0 };
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91 for (int i = 0; i < 32; i++) t[i] = x[i];
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92 for (int i = 32; i < 64; i++) t[i] = 0;
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93 barrett_reduce(r, t);
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94 }
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95
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96 public static unsafe void sc25519_from64bytes(sc25519* r, Byte* x) { //const unsigned char x[64]
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97 UInt32* t = stackalloc UInt32[64]; // { 0 };
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98 for (int i = 0; i < 64; i++) t[i] = x[i];
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99 barrett_reduce(r, t);
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100 }
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101
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102 /* XXX: What we actually want for crypto_group is probably just something like
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103 * void sc25519_frombytes(sc25519 *r, const unsigned char *x, size_t xlen)
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104 */
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105
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106 public static unsafe void sc25519_to32bytes(Byte* r, sc25519* x) { //unsigned char r[32]
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107 for (int i = 0; i < 32; i++) r[i] = (Byte)x->v[i];
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108 }
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109
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110 public static unsafe void sc25519_add(sc25519* r, sc25519* x, sc25519* y) {
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111 for (int i = 0; i < 32; i++) r->v[i] = x->v[i] + y->v[i];
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112 for (int i = 0; i < 31; i++) {
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113 uint carry = r->v[i] >> 8;
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114 r->v[i + 1] += carry;
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115 r->v[i] &= 0xff;
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116 }
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117 reduce_add_sub(r);
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118 }
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119
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120 public static unsafe void sc25519_mul(sc25519* r, sc25519* x, sc25519* y) {
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121 UInt32* t = stackalloc UInt32[64];
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122 for (int i = 0; i < 64; i++) t[i] = 0;
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123
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124 for (int i = 0; i < 32; i++)
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125 for (int j = 0; j < 32; j++)
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126 t[i + j] += x->v[i] * y->v[j];
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127
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128 /* Reduce coefficients */
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129 for (int i = 0; i < 63; i++) {
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130 uint carry = t[i] >> 8;
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131 t[i + 1] += carry;
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132 t[i] &= 0xff;
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133 }
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134
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135 barrett_reduce(r, t);
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136 }
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137
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138 public static unsafe void sc25519_square(sc25519* r, sc25519* x) {
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139 sc25519_mul(r, x, x);
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140 }
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141 }
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142 struct ge25519 {
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143 public fe25519 x;
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144 public fe25519 y;
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145 public fe25519 z;
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146 public fe25519 t;
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147
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148 struct ge25519_p1p1 {
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149 public fe25519 x;
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150 public fe25519 z;
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151 public fe25519 y;
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152 public fe25519 t;
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153 }
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154 struct ge25519_p2 {
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155 public fe25519 x;
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156 public fe25519 y;
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157 public fe25519 z;
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158 }
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159
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160 /* Windowsize for fixed-window scalar multiplication */
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161 const int WINDOWSIZE = 2; //#define WINDOWSIZE 2 /* Should be 1,2, or 4 */
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162 const int WINDOWMASK = ((1 << WINDOWSIZE) - 1); //#define WINDOWMASK ((1<<WINDOWSIZE)-1)
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163
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164 /* packed parameter d in the Edwards curve equation */
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165 static Byte[] ecd = new Byte[32] {0xA3, 0x78, 0x59, 0x13, 0xCA, 0x4D, 0xEB, 0x75, 0xAB, 0xD8, 0x41, 0x41, 0x4D, 0x0A, 0x70, 0x00,
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166 0x98, 0xE8, 0x79, 0x77, 0x79, 0x40, 0xC7, 0x8C, 0x73, 0xFE, 0x6F, 0x2B, 0xEE, 0x6C, 0x03, 0x52};
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167
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168 /* Packed coordinates of the base point */
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169 static Byte[] ge25519_base_x = new Byte[32] {0x1A, 0xD5, 0x25, 0x8F, 0x60, 0x2D, 0x56, 0xC9, 0xB2, 0xA7, 0x25, 0x95, 0x60, 0xC7, 0x2C, 0x69,
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170 0x5C, 0xDC, 0xD6, 0xFD, 0x31, 0xE2, 0xA4, 0xC0, 0xFE, 0x53, 0x6E, 0xCD, 0xD3, 0x36, 0x69, 0x21};
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171 static Byte[] ge25519_base_y = new Byte[32] {0x58, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
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172 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66};
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173 static Byte[] ge25519_base_z = new Byte[32] { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
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174 static Byte[] ge25519_base_t = new Byte[32] {0xA3, 0xDD, 0xB7, 0xA5, 0xB3, 0x8A, 0xDE, 0x6D, 0xF5, 0x52, 0x51, 0x77, 0x80, 0x9F, 0xF0, 0x20,
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175 0x7D, 0xE3, 0xAB, 0x64, 0x8E, 0x4E, 0xEA, 0x66, 0x65, 0x76, 0x8B, 0xD7, 0x0F, 0x5F, 0x87, 0x67};
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176
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177 /* Packed coordinates of the neutral element */
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178 static Byte[] ge25519_neutral_x = new Byte[32]; // { 0 };
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179 static Byte[] ge25519_neutral_y = new Byte[32] { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
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180 static Byte[] ge25519_neutral_z = new Byte[32] { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
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181 static Byte[] ge25519_neutral_t = new Byte[32]; // { 0 };
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182
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183 static unsafe void p1p1_to_p2(ge25519_p2* r, ge25519_p1p1* p) {
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184 fe25519.fe25519_mul(&r->x, &p->x, &p->t);
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185 fe25519.fe25519_mul(&r->y, &p->y, &p->z);
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186 fe25519.fe25519_mul(&r->z, &p->z, &p->t);
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187 }
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188
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189 static unsafe void p1p1_to_p3(ge25519* r, ge25519_p1p1* p) {
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190 p1p1_to_p2((ge25519_p2*)r, p);
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191 fe25519.fe25519_mul(&r->t, &p->x, &p->y);
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192 }
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193
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194 /* Constant-time version of: if(b) r = p */
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195 static unsafe void cmov_p3(ge25519* r, ge25519* p, Byte b) {
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196 fe25519.fe25519_cmov(&r->x, &p->x, b);
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197 fe25519.fe25519_cmov(&r->y, &p->y, b);
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198 fe25519.fe25519_cmov(&r->z, &p->z, b);
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199 fe25519.fe25519_cmov(&r->t, &p->t, b);
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200 }
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201
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202 /* See http://www.hyperelliptic.org/EFD/g1p/auto-twisted-extended-1.html#doubling-dbl-2008-hwcd */
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203 static unsafe void dbl_p1p1(ge25519_p1p1* r, ge25519_p2* p) {
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204 fe25519 a, b, c, d;
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205 fe25519.fe25519_square(&a, &p->x);
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206 fe25519.fe25519_square(&b, &p->y);
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207 fe25519.fe25519_square(&c, &p->z);
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208 fe25519.fe25519_add(&c, &c, &c);
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209 fe25519.fe25519_neg(&d, &a);
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210
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211 fe25519.fe25519_add(&r->x, &p->x, &p->y);
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212 fe25519.fe25519_square(&r->x, &r->x);
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213 fe25519.fe25519_sub(&r->x, &r->x, &a);
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214 fe25519.fe25519_sub(&r->x, &r->x, &b);
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215 fe25519.fe25519_add(&r->z, &d, &b);
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216 fe25519.fe25519_sub(&r->t, &r->z, &c);
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217 fe25519.fe25519_sub(&r->y, &d, &b);
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218 }
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219
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220 static unsafe void add_p1p1(ge25519_p1p1* r, ge25519* p, ge25519* q) {
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221 fe25519 a, b, c, d, t, fd;
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222 fixed (Byte* ecdp = ecd) fe25519.fe25519_unpack(&fd, ecdp);
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223
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224 fe25519.fe25519_sub(&a, &p->y, &p->x); // A = (Y1-X1)*(Y2-X2)
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225 fe25519.fe25519_sub(&t, &q->y, &q->x);
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226 fe25519.fe25519_mul(&a, &a, &t);
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227 fe25519.fe25519_add(&b, &p->x, &p->y); // B = (Y1+X1)*(Y2+X2)
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228 fe25519.fe25519_add(&t, &q->x, &q->y);
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229 fe25519.fe25519_mul(&b, &b, &t);
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230 fe25519.fe25519_mul(&c, &p->t, &q->t); //C = T1*k*T2
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231 fe25519.fe25519_mul(&c, &c, &fd);
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232 fe25519.fe25519_add(&c, &c, &c); //XXX: Can save this addition by precomputing 2*ecd
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233 fe25519.fe25519_mul(&d, &p->z, &q->z); //D = Z1*2*Z2
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234 fe25519.fe25519_add(&d, &d, &d);
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235 fe25519.fe25519_sub(&r->x, &b, &a); // E = B-A
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236 fe25519.fe25519_sub(&r->t, &d, &c); // F = D-C
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237 fe25519.fe25519_add(&r->z, &d, &c); // G = D+C
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238 fe25519.fe25519_add(&r->y, &b, &a); // H = B+A
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239 }
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240
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241 /* ********************************************************************
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242 * EXPORTED FUNCTIONS
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243 ******************************************************************** */
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244
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245 /* return 0 on success, -1 otherwise */
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246 public unsafe static Boolean ge25519_unpack_vartime(ge25519* r, Byte* p) { //const unsigned char p[32]
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247 Boolean ret;
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248 fe25519 t, fd;
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249 fe25519.fe25519_setone(&r->z);
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250 fixed (Byte* ecdp = ecd) fe25519.fe25519_unpack(&fd, ecdp);
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251 Byte par = (Byte)(p[31] >> 7);
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252 fe25519.fe25519_unpack(&r->y, p);
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253 fe25519.fe25519_square(&r->x, &r->y);
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254 fe25519.fe25519_mul(&t, &r->x, &fd);
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255 fe25519.fe25519_sub(&r->x, &r->x, &r->z);
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256 fe25519.fe25519_add(&t, &r->z, &t);
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257 fe25519.fe25519_invert(&t, &t);
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258 fe25519.fe25519_mul(&r->x, &r->x, &t);
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259 ret = fe25519.fe25519_sqrt_vartime(&r->x, &r->x, par);
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260 fe25519.fe25519_mul(&r->t, &r->x, &r->y);
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261 return ret;
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262 }
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263
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264 public static unsafe void ge25519_pack(Byte* r, ge25519* p) { //unsigned char r[32]
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265 fe25519 tx, ty, zi;
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266 fe25519.fe25519_invert(&zi, &p->z);
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267 fe25519.fe25519_mul(&tx, &p->x, &zi);
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268 fe25519.fe25519_mul(&ty, &p->y, &zi);
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269 fe25519.fe25519_pack(r, &ty);
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270 r[31] ^= (Byte)(fe25519.fe25519_getparity(&tx) << 7);
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271 }
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272
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273 public static unsafe void ge25519_add(ge25519* r, ge25519* p, ge25519* q) {
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274 ge25519_p1p1 grp1p1;
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275 add_p1p1(&grp1p1, p, q);
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276 p1p1_to_p3(r, &grp1p1);
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277 }
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278
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279 public static unsafe void ge25519_double(ge25519* r, ge25519* p) {
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280 ge25519_p1p1 grp1p1;
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281 dbl_p1p1(&grp1p1, (ge25519_p2*)p);
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282 p1p1_to_p3(r, &grp1p1);
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283 }
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284
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285 public static unsafe void ge25519_scalarmult(ge25519* r, ge25519* p, sc25519* s) {
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286 int i, j, k;
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287 ge25519 g;
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288 fixed (Byte* ge25519_neutral_xp = ge25519_neutral_x) fe25519.fe25519_unpack(&g.x, ge25519_neutral_xp);
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289 fixed (Byte* ge25519_neutral_yp = ge25519_neutral_y) fe25519.fe25519_unpack(&g.y, ge25519_neutral_yp);
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290 fixed (Byte* ge25519_neutral_zp = ge25519_neutral_z) fe25519.fe25519_unpack(&g.z, ge25519_neutral_zp);
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291 fixed (Byte* ge25519_neutral_tp = ge25519_neutral_t) fe25519.fe25519_unpack(&g.t, ge25519_neutral_tp);
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292
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293 ge25519[] pre = new ge25519[(1 << WINDOWSIZE)];
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294 ge25519 t;
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295 ge25519_p1p1 tp1p1;
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296 Byte w;
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297 Byte* sb = stackalloc Byte[32];
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298 sc25519.sc25519_to32bytes(sb, s);
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299
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300 // Precomputation
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301 pre[0] = g;
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302 pre[1] = *p;
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303 for (i = 2; i < (1 << WINDOWSIZE); i += 2) {
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304 fixed (ge25519* prep = pre) {
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305 dbl_p1p1(&tp1p1, (ge25519_p2*)(prep + i / 2));
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306 p1p1_to_p3(prep + i, &tp1p1);
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307 add_p1p1(&tp1p1, prep + i, prep + 1);
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308 p1p1_to_p3(prep + i + 1, &tp1p1);
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309 }
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310 }
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311
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312 // Fixed-window scalar multiplication
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313 for (i = 32; i > 0; i--) {
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314 for (j = 8 - WINDOWSIZE; j >= 0; j -= WINDOWSIZE) {
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315 for (k = 0; k < WINDOWSIZE - 1; k++) {
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316 dbl_p1p1(&tp1p1, (ge25519_p2*)&g);
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317 p1p1_to_p2((ge25519_p2*)&g, &tp1p1);
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318 }
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319 dbl_p1p1(&tp1p1, (ge25519_p2*)&g);
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320 p1p1_to_p3(&g, &tp1p1);
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321 // Cache-timing resistant loading of precomputed value:
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322 w = (Byte)((sb[i - 1] >> j) & WINDOWMASK);
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323 t = pre[0];
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324 for (k = 1; k < (1 << WINDOWSIZE); k++)
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325 fixed (ge25519* prekp = &pre[k]) cmov_p3(&t, prekp, (k == w) ? (Byte)1 : (Byte)0);
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326
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327 add_p1p1(&tp1p1, &g, &t);
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328 if (j != 0) p1p1_to_p2((ge25519_p2*)&g, &tp1p1);
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329 else p1p1_to_p3(&g, &tp1p1); /* convert to p3 representation at the end */
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330 }
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331 }
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332 r->x = g.x;
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333 r->y = g.y;
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334 r->z = g.z;
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335 r->t = g.t;
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336 }
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337
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338 public unsafe static void ge25519_scalarmult_base(ge25519* r, sc25519* s) {
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339 /* XXX: Better algorithm for known-base-point scalar multiplication */
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340 ge25519 t;
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341 fixed (Byte* ge25519_base_xp = ge25519_base_x) fe25519.fe25519_unpack(&t.x, ge25519_base_xp);
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342 fixed (Byte* ge25519_base_yp = ge25519_base_y) fe25519.fe25519_unpack(&t.y, ge25519_base_yp);
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343 fixed (Byte* ge25519_base_zp = ge25519_base_z) fe25519.fe25519_unpack(&t.z, ge25519_base_zp);
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344 fixed (Byte* ge25519_base_tp = ge25519_base_t) fe25519.fe25519_unpack(&t.t, ge25519_base_tp);
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345 ge25519_scalarmult(r, &t, s);
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346 }
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347 }
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348 unsafe struct fe25519 {
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349 public fixed UInt32 v[32]; // crypto_uint32 v[32];
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350
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351 const int WINDOWSIZE = 4; //#define WINDOWSIZE 4 /* Should be 1,2, or 4 */
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352 const int WINDOWMASK = ((1 << WINDOWSIZE) - 1); //#define WINDOWMASK ((1<<WINDOWSIZE)-1)
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353
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354 static unsafe void reduce_add_sub(fe25519* r) {
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355 for (int rep = 0; rep < 4; rep++) {
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356 UInt32 t = r->v[31] >> 7;
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357 r->v[31] &= 127;
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358 t *= 19;
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359 r->v[0] += t;
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360 for (int i = 0; i < 31; i++) {
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361 t = r->v[i] >> 8;
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362 r->v[i + 1] += t;
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363 r->v[i] &= 255;
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364 }
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365 }
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366 }
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367
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368 unsafe static void reduce_mul(fe25519* r) {
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369 for (int rep = 0; rep < 2; rep++) {
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370 UInt32 t = r->v[31] >> 7;
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371 r->v[31] &= 127;
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372 t *= 19;
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373 r->v[0] += t;
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374 for (int i = 0; i < 31; i++) {
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375 t = r->v[i] >> 8;
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376 r->v[i + 1] += t;
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377 r->v[i] &= 255;
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378 }
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379 }
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380 }
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381
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382 /* reduction modulo 2^255-19 */
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383 unsafe static void freeze(fe25519* r) {
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384 UInt32 m = (r->v[31] == 127) ? 1u : 0;
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385 for (int i = 30; i > 1; i--)
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386 m *= (r->v[i] == 255) ? 1u : 0;
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387 m *= (r->v[0] >= 237) ? 1u : 0;
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388
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389 r->v[31] -= m * 127;
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390 for (int i = 30; i > 0; i--)
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391 r->v[i] -= m * 255;
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392 r->v[0] -= m * 237;
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393 }
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394
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395 /*freeze input before calling isone*/
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396 unsafe static Boolean isone(fe25519* x) {
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397 bool r = x->v[0] == 1;
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398 for (int i = 1; i < 32; i++) r &= (x->v[i] == 0);
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399 return r;
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400 }
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401
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402 /*freeze input before calling iszero*/
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403 unsafe static Boolean iszero(fe25519* x) {
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404 bool r = (x->v[0] == 0);
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405 for (int i = 1; i < 32; i++) r &= (x->v[i] == 0);
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406 return r;
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407 }
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408
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409
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410 unsafe static Boolean issquare(fe25519* x) {
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411 Byte[] e = new Byte[32] { 0xf6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3f }; /* (p-1)/2 */
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412 fe25519 t;
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413
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414 fixed (Byte* ep = e) fe25519_pow(&t, x, ep);
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415 freeze(&t);
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416 return isone(&t) || iszero(&t);
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417 }
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418
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419 public static unsafe void fe25519_unpack(fe25519* r, Byte* x) { //const unsigned char x[32]
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420 for (int i = 0; i < 32; i++) r->v[i] = x[i];
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421 r->v[31] &= 127;
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422 }
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423
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424 /* Assumes input x being reduced mod 2^255 */
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425 public static unsafe void fe25519_pack(Byte* r, fe25519* x) { //unsigned char r[32]
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426 for (int i = 0; i < 32; i++)
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427 r[i] = (byte)x->v[i];
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428
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429 /* freeze byte array */
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430 UInt32 m = (r[31] == 127) ? 1u : 0; /* XXX: some compilers might use branches; fix */
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431 for (int i = 30; i > 1; i--)
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432 m *= (r[i] == 255) ? 1u : 0;
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433 m *= (r[0] >= 237) ? 1u : 0;
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434 r[31] -= (byte)(m * 127);
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diff changeset
435 for (int i = 30; i > 0; i--)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
436 r[i] -= (byte)(m * 255);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
437 r[0] -= (byte)(m * 237);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
438 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
439
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
440 public static unsafe void fe25519_cmov(fe25519* r, fe25519* x, Byte b) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
441 Byte nb = (Byte)(1 - b);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
442 for (int i = 0; i < 32; i++) r->v[i] = nb * r->v[i] + b * x->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
443 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
444
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
445 public static unsafe Byte fe25519_getparity(fe25519* x) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
446 fe25519 t = new fe25519();
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
447 for (int i = 0; i < 32; i++) t.v[i] = x->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
448 freeze(&t);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
449 return (Byte)(t.v[0] & 1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
450 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
451
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
452 public static unsafe void fe25519_setone(fe25519* r) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
453 r->v[0] = 1;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
454 for (int i = 1; i < 32; i++) r->v[i] = 0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
455 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
456
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
457 static unsafe void fe25519_setzero(fe25519* r) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
458 for (int i = 0; i < 32; i++) r->v[i] = 0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
459 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
460
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
461 public static unsafe void fe25519_neg(fe25519* r, fe25519* x) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
462 fe25519 t = new fe25519();
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
463 for (int i = 0; i < 32; i++) t.v[i] = x->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
464 fe25519_setzero(r);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
465 fe25519_sub(r, r, &t);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
466 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
467
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
468 public static unsafe void fe25519_add(fe25519* r, fe25519* x, fe25519* y) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
469 for (int i = 0; i < 32; i++) r->v[i] = x->v[i] + y->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
470 reduce_add_sub(r);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
471 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
472
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
473 public static unsafe void fe25519_sub(fe25519* r, fe25519* x, fe25519* y) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
474 UInt32* t = stackalloc UInt32[32];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
475 t[0] = x->v[0] + 0x1da;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
476 t[31] = x->v[31] + 0xfe;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
477 for (int i = 1; i < 31; i++) t[i] = x->v[i] + 0x1fe;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
478 for (int i = 0; i < 32; i++) r->v[i] = t[i] - y->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
479 reduce_add_sub(r);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
480 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
481
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
482 public static unsafe void fe25519_mul(fe25519* r, fe25519* x, fe25519* y) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
483 UInt32* t = stackalloc UInt32[63];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
484 for (int i = 0; i < 63; i++) t[i] = 0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
485 for (int i = 0; i < 32; i++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
486 for (int j = 0; j < 32; j++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
487 t[i + j] += x->v[i] * y->v[j];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
488
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
489 for (int i = 32; i < 63; i++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
490 r->v[i - 32] = t[i - 32] + 38 * t[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
491 r->v[31] = t[31]; /* result now in r[0]...r[31] */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
492
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
493 reduce_mul(r);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
494 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
495
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
496 public static unsafe void fe25519_square(fe25519* r, fe25519* x) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
497 fe25519_mul(r, x, x);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
498 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
499
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
500 /*XXX: Make constant time! */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
501 public static unsafe void fe25519_pow(fe25519* r, fe25519* x, Byte* e) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
502 /*
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
503 fe25519 g;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
504 fe25519_setone(&g);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
505 int i;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
506 unsigned char j;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
507 for(i=32;i>0;i--)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
508 {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
509 for(j=128;j>0;j>>=1)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
510 {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
511 fe25519_square(&g,&g);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
512 if(e[i-1] & j)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
513 fe25519_mul(&g,&g,x);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
514 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
515 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
516 for(i=0;i<32;i++) r->v[i] = g.v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
517 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
518 fe25519 g;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
519 fe25519_setone(&g);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
520 fe25519[] pre = new fe25519[(1 << WINDOWSIZE)];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
521 fe25519 t;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
522 Byte w;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
523
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
524 // Precomputation
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
525 fixed (fe25519* prep = pre) fe25519_setone(prep);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
526 pre[1] = *x;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
527 for (int i = 2; i < (1 << WINDOWSIZE); i += 2) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
528 fixed (fe25519* prep = pre) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
529 fe25519_square(prep + i, prep + i / 2);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
530 fe25519_mul(prep + i + 1, prep + i, prep + 1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
531 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
532 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
533
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
534 // Fixed-window scalar multiplication
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
535 for (int i = 32; i > 0; i--) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
536 for (int j = 8 - WINDOWSIZE; j >= 0; j -= WINDOWSIZE) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
537 for (int k = 0; k < WINDOWSIZE; k++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
538 fe25519_square(&g, &g);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
539 // Cache-timing resistant loading of precomputed value:
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
540 w = (Byte)((e[i - 1] >> j) & WINDOWMASK);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
541 t = pre[0];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
542 for (int k = 1; k < (1 << WINDOWSIZE); k++) fixed (fe25519* prekp = &pre[k]) fe25519_cmov(&t, prekp, (k == w) ? (Byte)1 : (Byte)0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
543 fe25519_mul(&g, &g, &t);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
544 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
545 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
546 *r = g;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
547 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
548
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
549 /* Return 0 on success, 1 otherwise */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
550 public static unsafe Boolean fe25519_sqrt_vartime(fe25519* r, fe25519* x, Byte parity) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
551 /* See HAC, Alg. 3.37 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
552 if (!issquare(x)) return true;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
553 Byte[] e = new Byte[32] { 0xfb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1f }; /* (p-1)/4 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
554 Byte[] e2 = new Byte[32] { 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0f }; /* (p+3)/8 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
555 Byte[] e3 = new Byte[32] { 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0f }; /* (p-5)/8 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
556 fe25519 p = new fe25519(); // { { 0 } };
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
557 fe25519 d;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
558 fixed (Byte* ep = e) fe25519.fe25519_pow(&d, x, ep);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
559 freeze(&d);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
560 if (isone(&d))
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
561 fixed (Byte* e2p = e2) fe25519.fe25519_pow(r, x, e2p);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
562 else {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
563 for (int i = 0; i < 32; i++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
564 d.v[i] = 4 * x->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
565 fixed (Byte* e3p = e3) fe25519.fe25519_pow(&d, &d, e3p);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
566 for (int i = 0; i < 32; i++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
567 r->v[i] = 2 * x->v[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
568 fe25519_mul(r, r, &d);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
569 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
570 freeze(r);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
571 if ((r->v[0] & 1) != (parity & 1)) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
572 fe25519_sub(r, &p, r);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
573 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
574 return false;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
575 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
576
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
577 public static unsafe void fe25519_invert(fe25519* r, fe25519* x) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
578 fe25519 z2;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
579 fe25519 z9;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
580 fe25519 z11;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
581 fe25519 z2_5_0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
582 fe25519 z2_10_0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
583 fe25519 z2_20_0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
584 fe25519 z2_50_0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
585 fe25519 z2_100_0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
586 fe25519 t0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
587 fe25519 t1;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
588
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
589 /* 2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
590 fe25519_square(&z2, x);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
591 /* 4 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
592 fe25519_square(&t1, &z2);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
593 /* 8 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
594 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
595 /* 9 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
596 fe25519_mul(&z9, &t0, x);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
597 /* 11 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
598 fe25519_mul(&z11, &z9, &z2);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
599 /* 22 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
600 fe25519_square(&t0, &z11);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
601 /* 2^5 - 2^0 = 31 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
602 fe25519_mul(&z2_5_0, &t0, &z9);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
603
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
604 /* 2^6 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
605 fe25519_square(&t0, &z2_5_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
606 /* 2^7 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
607 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
608 /* 2^8 - 2^3 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
609 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
610 /* 2^9 - 2^4 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
611 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
612 /* 2^10 - 2^5 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
613 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
614 /* 2^10 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
615 fe25519_mul(&z2_10_0, &t0, &z2_5_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
616
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
617 /* 2^11 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
618 fe25519_square(&t0, &z2_10_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
619 /* 2^12 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
620 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
621 /* 2^20 - 2^10 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
622 for (int i = 2; i < 10; i += 2) { fe25519_square(&t0, &t1); fe25519_square(&t1, &t0); }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
623 /* 2^20 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
624 fe25519_mul(&z2_20_0, &t1, &z2_10_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
625
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
626 /* 2^21 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
627 fe25519_square(&t0, &z2_20_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
628 /* 2^22 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
629 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
630 /* 2^40 - 2^20 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
631 for (int i = 2; i < 20; i += 2) { fe25519_square(&t0, &t1); fe25519_square(&t1, &t0); }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
632 /* 2^40 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
633 fe25519_mul(&t0, &t1, &z2_20_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
634
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
635 /* 2^41 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
636 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
637 /* 2^42 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
638 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
639 /* 2^50 - 2^10 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
640 for (int i = 2; i < 10; i += 2) { fe25519_square(&t1, &t0); fe25519_square(&t0, &t1); }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
641 /* 2^50 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
642 fe25519_mul(&z2_50_0, &t0, &z2_10_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
643
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
644 /* 2^51 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
645 fe25519_square(&t0, &z2_50_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
646 /* 2^52 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
647 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
648 /* 2^100 - 2^50 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
649 for (int i = 2; i < 50; i += 2) { fe25519_square(&t0, &t1); fe25519_square(&t1, &t0); }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
650 /* 2^100 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
651 fe25519_mul(&z2_100_0, &t1, &z2_50_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
652
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
653 /* 2^101 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
654 fe25519_square(&t1, &z2_100_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
655 /* 2^102 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
656 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
657 /* 2^200 - 2^100 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
658 for (int i = 2; i < 100; i += 2) { fe25519_square(&t1, &t0); fe25519_square(&t0, &t1); }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
659 /* 2^200 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
660 fe25519_mul(&t1, &t0, &z2_100_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
661
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
662 /* 2^201 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
663 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
664 /* 2^202 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
665 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
666 /* 2^250 - 2^50 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
667 for (int i = 2; i < 50; i += 2) { fe25519_square(&t0, &t1); fe25519_square(&t1, &t0); }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
668 /* 2^250 - 2^0 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
669 fe25519_mul(&t0, &t1, &z2_50_0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
670
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
671 /* 2^251 - 2^1 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
672 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
673 /* 2^252 - 2^2 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
674 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
675 /* 2^253 - 2^3 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
676 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
677 /* 2^254 - 2^4 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
678 fe25519_square(&t0, &t1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
679 /* 2^255 - 2^5 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
680 fe25519_square(&t1, &t0);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
681 /* 2^255 - 21 */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
682 fe25519_mul(r, &t1, &z11);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
683 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
684 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
685
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
686 public static unsafe void crypto_sign_keypair(out Byte[] pk, out Byte[] sk) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
687 sc25519 scsk;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
688 ge25519 gepk;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
689
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
690 sk = new Byte[SECRETKEYBYTES];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
691 pk = new Byte[PUBLICKEYBYTES];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
692 randombytes.generate(sk);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
693 fixed (Byte* skp = sk) crypto_hash.sha512.crypto_hash(skp, skp, 32);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
694 sk[0] &= 248;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
695 sk[31] &= 127;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
696 sk[31] |= 64;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
697
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
698 fixed (Byte* skp = sk) sc25519.sc25519_from32bytes(&scsk, skp);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
699
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
700 ge25519.ge25519_scalarmult_base(&gepk, &scsk);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
701 fixed (Byte* pkp = pk) ge25519.ge25519_pack(pkp, &gepk);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
702 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
703
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
704 public static unsafe Byte[] crypto_sign(Byte[] m, Byte[] sk) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
705 if (sk.Length != SECRETKEYBYTES) throw new ArgumentException("sk.Length != SECRETKEYBYTES");
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
706 Byte[] sm = new Byte[m.Length + 64];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
707 UInt64 smlen;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
708 fixed (Byte* smp = sm, mp = m, skp = sk) crypto_sign(smp, out smlen, mp, (ulong)m.Length, skp);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
709 return sm;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
710 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
711 public static unsafe void crypto_sign(Byte* sm, out UInt64 smlen, Byte* m, UInt64 mlen, Byte* sk) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
712 sc25519 sck, scs, scsk;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
713 ge25519 ger;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
714 Byte* r = stackalloc Byte[32];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
715 Byte* s = stackalloc Byte[32];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
716 Byte* hmg = stackalloc Byte[crypto_hash.sha512.BYTES];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
717 Byte* hmr = stackalloc Byte[crypto_hash.sha512.BYTES];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
718
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
719 smlen = mlen + 64;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
720 for (UInt64 i = 0; i < mlen; i++) sm[32 + i] = m[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
721 for (int i = 0; i < 32; i++) sm[i] = sk[32 + i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
722 crypto_hash.sha512.crypto_hash(hmg, sm, mlen + 32); /* Generate k as h(m,sk[32],...,sk[63]) */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
723
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
724 sc25519.sc25519_from64bytes(&sck, hmg);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
725 ge25519.ge25519_scalarmult_base(&ger, &sck);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
726 ge25519.ge25519_pack(r, &ger);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
727
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
728 for (int i = 0; i < 32; i++) sm[i] = r[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
729
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
730 crypto_hash.sha512.crypto_hash(hmr, sm, mlen + 32); /* Compute h(m,r) */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
731 sc25519.sc25519_from64bytes(&scs, hmr);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
732 sc25519.sc25519_mul(&scs, &scs, &sck);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
733
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
734 sc25519.sc25519_from32bytes(&scsk, sk);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
735 sc25519.sc25519_add(&scs, &scs, &scsk);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
736
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
737 sc25519.sc25519_to32bytes(s, &scs); /* cat s */
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
738 for (UInt64 i = 0; i < 32; i++)
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
739 sm[mlen + 32 + i] = s[i];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
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740 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
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741
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
742 public static unsafe Byte[] crypto_sign_open(Byte[] sm, Byte[] pk) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
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743 if (pk.Length != PUBLICKEYBYTES) throw new ArgumentException("pk.Length != PUBLICKEYBYTES");
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
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744 Byte[] m = new Byte[sm.Length - 64];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
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745 UInt64 mlen;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
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746 fixed (Byte* smp = sm, mp = m, pkp = pk) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
747 if (crypto_sign_open(mp, out mlen, smp, (ulong)sm.Length, pkp) != 0) return null;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
748 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
749 return m;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
750 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
751 public static unsafe int crypto_sign_open(Byte* m, out UInt64 mlen, Byte* sm, UInt64 smlen, Byte* pk) {
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
752 mlen = 0;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
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753 if (smlen < 64) return -1;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
754
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
755 Byte* t1 = stackalloc Byte[32], t2 = stackalloc Byte[32];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
756 ge25519 get1, get2, gepk;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
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diff changeset
757 sc25519 schmr, scs;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
758 Byte* hmr = stackalloc Byte[crypto_hash.sha512.BYTES];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
759
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
760 if (ge25519.ge25519_unpack_vartime(&get1, sm)) return -1;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
761 if (ge25519.ge25519_unpack_vartime(&gepk, pk)) return -1;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
762
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
763 crypto_hash.sha512.crypto_hash(hmr, sm, smlen - 32);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
764
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
765 sc25519.sc25519_from64bytes(&schmr, hmr);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
766 ge25519.ge25519_scalarmult(&get1, &get1, &schmr);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
767 ge25519.ge25519_add(&get1, &get1, &gepk);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
768 ge25519.ge25519_pack(t1, &get1);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
769
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
770 sc25519.sc25519_from32bytes(&scs, &sm[smlen - 32]);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
771 ge25519.ge25519_scalarmult_base(&get2, &scs);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
772 ge25519.ge25519_pack(t2, &get2);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
773
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
774 if (m != null) for (UInt64 i = 0; i < smlen - 64; i++) m[i] = sm[i + 32];
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
775 mlen = smlen - 64;
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
776
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
777 return crypto_verify._32.crypto_verify(t1, t2);
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
778 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
779 }
c873e3dd73fe Added NaCl cryptography code
Ivo Smits <Ivo@UCIS.nl>
parents:
diff changeset
780 }