| | | 1 | | using System; |
| | | 2 | | |
| | | 3 | | namespace Renci.SshNet.Security.Chaos.NaCl.Internal.Ed25519Ref10 |
| | | 4 | | { |
| | | 5 | | internal static class MontgomeryOperations |
| | | 6 | | { |
| | | 7 | | internal static void scalarmult( |
| | | 8 | | byte[] q, int qoffset, |
| | | 9 | | byte[] n, int noffset, |
| | | 10 | | byte[] p, int poffset) |
| | 2344 | 11 | | { |
| | | 12 | | FieldElement p0; |
| | | 13 | | FieldElement q0; |
| | 2344 | 14 | | FieldOperations.fe_frombytes2(out p0, p, poffset); |
| | 2344 | 15 | | scalarmult(out q0, n, noffset, ref p0); |
| | 2344 | 16 | | FieldOperations.fe_tobytes(q, qoffset, ref q0); |
| | 2344 | 17 | | } |
| | | 18 | | |
| | | 19 | | internal static void scalarmult( |
| | | 20 | | out FieldElement q, |
| | | 21 | | byte[] n, int noffset, |
| | | 22 | | ref FieldElement p) |
| | 2344 | 23 | | { |
| | 2344 | 24 | | byte[] e = new byte[32];//ToDo: remove allocation |
| | | 25 | | UInt32 i; |
| | | 26 | | FieldElement x1; |
| | | 27 | | FieldElement x2; |
| | | 28 | | FieldElement z2; |
| | | 29 | | FieldElement x3; |
| | | 30 | | FieldElement z3; |
| | | 31 | | FieldElement tmp0; |
| | | 32 | | FieldElement tmp1; |
| | | 33 | | int pos; |
| | | 34 | | UInt32 swap; |
| | | 35 | | UInt32 b; |
| | | 36 | | |
| | 154704 | 37 | | for (i = 0; i < 32; ++i) |
| | 75008 | 38 | | e[i] = n[noffset + i]; |
| | 2344 | 39 | | ScalarOperations.sc_clamp(e, 0); |
| | 2344 | 40 | | x1 = p; |
| | 2344 | 41 | | FieldOperations.fe_1(out x2); |
| | 2344 | 42 | | FieldOperations.fe_0(out z2); |
| | 2344 | 43 | | x3 = x1; |
| | 2344 | 44 | | FieldOperations.fe_1(out z3); |
| | | 45 | | |
| | 2344 | 46 | | swap = 0; |
| | 1200128 | 47 | | for (pos = 254; pos >= 0; --pos) |
| | 597720 | 48 | | { |
| | 597720 | 49 | | b = (uint)(e[pos / 8] >> (pos & 7)); |
| | 597720 | 50 | | b &= 1; |
| | 597720 | 51 | | swap ^= b; |
| | 597720 | 52 | | FieldOperations.fe_cswap(ref x2, ref x3, swap); |
| | 597720 | 53 | | FieldOperations.fe_cswap(ref z2, ref z3, swap); |
| | 597720 | 54 | | swap = b; |
| | | 55 | | /* qhasm: fe X2 */ |
| | | 56 | | |
| | | 57 | | /* qhasm: fe Z2 */ |
| | | 58 | | |
| | | 59 | | /* qhasm: fe X3 */ |
| | | 60 | | |
| | | 61 | | /* qhasm: fe Z3 */ |
| | | 62 | | |
| | | 63 | | /* qhasm: fe X4 */ |
| | | 64 | | |
| | | 65 | | /* qhasm: fe Z4 */ |
| | | 66 | | |
| | | 67 | | /* qhasm: fe X5 */ |
| | | 68 | | |
| | | 69 | | /* qhasm: fe Z5 */ |
| | | 70 | | |
| | | 71 | | /* qhasm: fe A */ |
| | | 72 | | |
| | | 73 | | /* qhasm: fe B */ |
| | | 74 | | |
| | | 75 | | /* qhasm: fe C */ |
| | | 76 | | |
| | | 77 | | /* qhasm: fe D */ |
| | | 78 | | |
| | | 79 | | /* qhasm: fe E */ |
| | | 80 | | |
| | | 81 | | /* qhasm: fe AA */ |
| | | 82 | | |
| | | 83 | | /* qhasm: fe BB */ |
| | | 84 | | |
| | | 85 | | /* qhasm: fe DA */ |
| | | 86 | | |
| | | 87 | | /* qhasm: fe CB */ |
| | | 88 | | |
| | | 89 | | /* qhasm: fe t0 */ |
| | | 90 | | |
| | | 91 | | /* qhasm: fe t1 */ |
| | | 92 | | |
| | | 93 | | /* qhasm: fe t2 */ |
| | | 94 | | |
| | | 95 | | /* qhasm: fe t3 */ |
| | | 96 | | |
| | | 97 | | /* qhasm: fe t4 */ |
| | | 98 | | |
| | | 99 | | /* qhasm: enter ladder */ |
| | | 100 | | |
| | | 101 | | /* qhasm: D = X3-Z3 */ |
| | | 102 | | /* asm 1: fe_sub(>D=fe#5,<X3=fe#3,<Z3=fe#4); */ |
| | | 103 | | /* asm 2: fe_sub(>D=tmp0,<X3=x3,<Z3=z3); */ |
| | 597720 | 104 | | FieldOperations.fe_sub(out tmp0, ref x3, ref z3); |
| | | 105 | | |
| | | 106 | | /* qhasm: B = X2-Z2 */ |
| | | 107 | | /* asm 1: fe_sub(>B=fe#6,<X2=fe#1,<Z2=fe#2); */ |
| | | 108 | | /* asm 2: fe_sub(>B=tmp1,<X2=x2,<Z2=z2); */ |
| | 597720 | 109 | | FieldOperations.fe_sub(out tmp1, ref x2, ref z2); |
| | | 110 | | |
| | | 111 | | /* qhasm: A = X2+Z2 */ |
| | | 112 | | /* asm 1: fe_add(>A=fe#1,<X2=fe#1,<Z2=fe#2); */ |
| | | 113 | | /* asm 2: fe_add(>A=x2,<X2=x2,<Z2=z2); */ |
| | 597720 | 114 | | FieldOperations.fe_add(out x2, ref x2, ref z2); |
| | | 115 | | |
| | | 116 | | /* qhasm: C = X3+Z3 */ |
| | | 117 | | /* asm 1: fe_add(>C=fe#2,<X3=fe#3,<Z3=fe#4); */ |
| | | 118 | | /* asm 2: fe_add(>C=z2,<X3=x3,<Z3=z3); */ |
| | 597720 | 119 | | FieldOperations.fe_add(out z2, ref x3, ref z3); |
| | | 120 | | |
| | | 121 | | /* qhasm: DA = D*A */ |
| | | 122 | | /* asm 1: fe_mul(>DA=fe#4,<D=fe#5,<A=fe#1); */ |
| | | 123 | | /* asm 2: fe_mul(>DA=z3,<D=tmp0,<A=x2); */ |
| | 597720 | 124 | | FieldOperations.fe_mul(out z3, ref tmp0, ref x2); |
| | | 125 | | |
| | | 126 | | /* qhasm: CB = C*B */ |
| | | 127 | | /* asm 1: fe_mul(>CB=fe#2,<C=fe#2,<B=fe#6); */ |
| | | 128 | | /* asm 2: fe_mul(>CB=z2,<C=z2,<B=tmp1); */ |
| | 597720 | 129 | | FieldOperations.fe_mul(out z2, ref z2, ref tmp1); |
| | | 130 | | |
| | | 131 | | /* qhasm: BB = B^2 */ |
| | | 132 | | /* asm 1: fe_sq(>BB=fe#5,<B=fe#6); */ |
| | | 133 | | /* asm 2: fe_sq(>BB=tmp0,<B=tmp1); */ |
| | 597720 | 134 | | FieldOperations.fe_sq(out tmp0, ref tmp1); |
| | | 135 | | |
| | | 136 | | /* qhasm: AA = A^2 */ |
| | | 137 | | /* asm 1: fe_sq(>AA=fe#6,<A=fe#1); */ |
| | | 138 | | /* asm 2: fe_sq(>AA=tmp1,<A=x2); */ |
| | 597720 | 139 | | FieldOperations.fe_sq(out tmp1, ref x2); |
| | | 140 | | |
| | | 141 | | /* qhasm: t0 = DA+CB */ |
| | | 142 | | /* asm 1: fe_add(>t0=fe#3,<DA=fe#4,<CB=fe#2); */ |
| | | 143 | | /* asm 2: fe_add(>t0=x3,<DA=z3,<CB=z2); */ |
| | 597720 | 144 | | FieldOperations.fe_add(out x3, ref z3, ref z2); |
| | | 145 | | |
| | | 146 | | /* qhasm: assign x3 to t0 */ |
| | | 147 | | |
| | | 148 | | /* qhasm: t1 = DA-CB */ |
| | | 149 | | /* asm 1: fe_sub(>t1=fe#2,<DA=fe#4,<CB=fe#2); */ |
| | | 150 | | /* asm 2: fe_sub(>t1=z2,<DA=z3,<CB=z2); */ |
| | 597720 | 151 | | FieldOperations.fe_sub(out z2, ref z3, ref z2); |
| | | 152 | | |
| | | 153 | | /* qhasm: X4 = AA*BB */ |
| | | 154 | | /* asm 1: fe_mul(>X4=fe#1,<AA=fe#6,<BB=fe#5); */ |
| | | 155 | | /* asm 2: fe_mul(>X4=x2,<AA=tmp1,<BB=tmp0); */ |
| | 597720 | 156 | | FieldOperations.fe_mul(out x2, ref tmp1, ref tmp0); |
| | | 157 | | |
| | | 158 | | /* qhasm: E = AA-BB */ |
| | | 159 | | /* asm 1: fe_sub(>E=fe#6,<AA=fe#6,<BB=fe#5); */ |
| | | 160 | | /* asm 2: fe_sub(>E=tmp1,<AA=tmp1,<BB=tmp0); */ |
| | 597720 | 161 | | FieldOperations.fe_sub(out tmp1, ref tmp1, ref tmp0); |
| | | 162 | | |
| | | 163 | | /* qhasm: t2 = t1^2 */ |
| | | 164 | | /* asm 1: fe_sq(>t2=fe#2,<t1=fe#2); */ |
| | | 165 | | /* asm 2: fe_sq(>t2=z2,<t1=z2); */ |
| | 597720 | 166 | | FieldOperations.fe_sq(out z2, ref z2); |
| | | 167 | | |
| | | 168 | | /* qhasm: t3 = a24*E */ |
| | | 169 | | /* asm 1: fe_mul121666(>t3=fe#4,<E=fe#6); */ |
| | | 170 | | /* asm 2: fe_mul121666(>t3=z3,<E=tmp1); */ |
| | 597720 | 171 | | FieldOperations.fe_mul121666(out z3, ref tmp1); |
| | | 172 | | |
| | | 173 | | /* qhasm: X5 = t0^2 */ |
| | | 174 | | /* asm 1: fe_sq(>X5=fe#3,<t0=fe#3); */ |
| | | 175 | | /* asm 2: fe_sq(>X5=x3,<t0=x3); */ |
| | 597720 | 176 | | FieldOperations.fe_sq(out x3, ref x3); |
| | | 177 | | |
| | | 178 | | /* qhasm: t4 = BB+t3 */ |
| | | 179 | | /* asm 1: fe_add(>t4=fe#5,<BB=fe#5,<t3=fe#4); */ |
| | | 180 | | /* asm 2: fe_add(>t4=tmp0,<BB=tmp0,<t3=z3); */ |
| | 597720 | 181 | | FieldOperations.fe_add(out tmp0, ref tmp0, ref z3); |
| | | 182 | | |
| | | 183 | | /* qhasm: Z5 = X1*t2 */ |
| | | 184 | | /* asm 1: fe_mul(>Z5=fe#4,x1,<t2=fe#2); */ |
| | | 185 | | /* asm 2: fe_mul(>Z5=z3,x1,<t2=z2); */ |
| | 597720 | 186 | | FieldOperations.fe_mul(out z3, ref x1, ref z2); |
| | | 187 | | |
| | | 188 | | /* qhasm: Z4 = E*t4 */ |
| | | 189 | | /* asm 1: fe_mul(>Z4=fe#2,<E=fe#6,<t4=fe#5); */ |
| | | 190 | | /* asm 2: fe_mul(>Z4=z2,<E=tmp1,<t4=tmp0); */ |
| | 597720 | 191 | | FieldOperations.fe_mul(out z2, ref tmp1, ref tmp0); |
| | | 192 | | |
| | | 193 | | /* qhasm: return */ |
| | | 194 | | |
| | 597720 | 195 | | } |
| | 2344 | 196 | | FieldOperations.fe_cswap(ref x2, ref x3, swap); |
| | 2344 | 197 | | FieldOperations.fe_cswap(ref z2, ref z3, swap); |
| | | 198 | | |
| | 2344 | 199 | | FieldOperations.fe_invert(out z2, ref z2); |
| | 2344 | 200 | | FieldOperations.fe_mul(out x2, ref x2, ref z2); |
| | 2344 | 201 | | q = x2; |
| | 2344 | 202 | | CryptoBytes.Wipe(e); |
| | 2344 | 203 | | } |
| | | 204 | | } |
| | | 205 | | } |