Xuyi Wang
/
wolfSSL
Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
wolfcrypt/src/ge_low_mem.c@4:1b0d80432c79, 2016-04-28 (annotated)
- Committer:
- wolfSSL
- Date:
- Thu Apr 28 00:57:21 2016 +0000
- Revision:
- 4:1b0d80432c79
wolfSSL 3.9.0
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| wolfSSL | 4:1b0d80432c79 | 1 | /* ge_low_mem.c |
| wolfSSL | 4:1b0d80432c79 | 2 | * |
| wolfSSL | 4:1b0d80432c79 | 3 | * Copyright (C) 2006-2016 wolfSSL Inc. |
| wolfSSL | 4:1b0d80432c79 | 4 | * |
| wolfSSL | 4:1b0d80432c79 | 5 | * This file is part of wolfSSL. |
| wolfSSL | 4:1b0d80432c79 | 6 | * |
| wolfSSL | 4:1b0d80432c79 | 7 | * wolfSSL is free software; you can redistribute it and/or modify |
| wolfSSL | 4:1b0d80432c79 | 8 | * it under the terms of the GNU General Public License as published by |
| wolfSSL | 4:1b0d80432c79 | 9 | * the Free Software Foundation; either version 2 of the License, or |
| wolfSSL | 4:1b0d80432c79 | 10 | * (at your option) any later version. |
| wolfSSL | 4:1b0d80432c79 | 11 | * |
| wolfSSL | 4:1b0d80432c79 | 12 | * wolfSSL is distributed in the hope that it will be useful, |
| wolfSSL | 4:1b0d80432c79 | 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| wolfSSL | 4:1b0d80432c79 | 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| wolfSSL | 4:1b0d80432c79 | 15 | * GNU General Public License for more details. |
| wolfSSL | 4:1b0d80432c79 | 16 | * |
| wolfSSL | 4:1b0d80432c79 | 17 | * You should have received a copy of the GNU General Public License |
| wolfSSL | 4:1b0d80432c79 | 18 | * along with this program; if not, write to the Free Software |
| wolfSSL | 4:1b0d80432c79 | 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA |
| wolfSSL | 4:1b0d80432c79 | 20 | */ |
| wolfSSL | 4:1b0d80432c79 | 21 | |
| wolfSSL | 4:1b0d80432c79 | 22 | |
| wolfSSL | 4:1b0d80432c79 | 23 | /* Based from Daniel Beer's public domain work. */ |
| wolfSSL | 4:1b0d80432c79 | 24 | |
| wolfSSL | 4:1b0d80432c79 | 25 | #ifdef HAVE_CONFIG_H |
| wolfSSL | 4:1b0d80432c79 | 26 | #include <config.h> |
| wolfSSL | 4:1b0d80432c79 | 27 | #endif |
| wolfSSL | 4:1b0d80432c79 | 28 | |
| wolfSSL | 4:1b0d80432c79 | 29 | #include <wolfssl/wolfcrypt/settings.h> |
| wolfSSL | 4:1b0d80432c79 | 30 | |
| wolfSSL | 4:1b0d80432c79 | 31 | #if defined(CURVED25519_SMALL) /* use slower code that takes less memory */ |
| wolfSSL | 4:1b0d80432c79 | 32 | #if defined(HAVE_ED25519) |
| wolfSSL | 4:1b0d80432c79 | 33 | |
| wolfSSL | 4:1b0d80432c79 | 34 | #include <wolfssl/wolfcrypt/ge_operations.h> |
| wolfSSL | 4:1b0d80432c79 | 35 | #include <wolfssl/wolfcrypt/error-crypt.h> |
| wolfSSL | 4:1b0d80432c79 | 36 | #ifdef NO_INLINE |
| wolfSSL | 4:1b0d80432c79 | 37 | #include <wolfssl/wolfcrypt/misc.h> |
| wolfSSL | 4:1b0d80432c79 | 38 | #else |
| wolfSSL | 4:1b0d80432c79 | 39 | #include <wolfcrypt/src/misc.c> |
| wolfSSL | 4:1b0d80432c79 | 40 | #endif |
| wolfSSL | 4:1b0d80432c79 | 41 | |
| wolfSSL | 4:1b0d80432c79 | 42 | void ed25519_smult(ge_p3 *r, const ge_p3 *a, const byte *e); |
| wolfSSL | 4:1b0d80432c79 | 43 | void ed25519_add(ge_p3 *r, const ge_p3 *a, const ge_p3 *b); |
| wolfSSL | 4:1b0d80432c79 | 44 | void ed25519_double(ge_p3 *r, const ge_p3 *a); |
| wolfSSL | 4:1b0d80432c79 | 45 | |
| wolfSSL | 4:1b0d80432c79 | 46 | |
| wolfSSL | 4:1b0d80432c79 | 47 | static const byte ed25519_order[F25519_SIZE] = { |
| wolfSSL | 4:1b0d80432c79 | 48 | 0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58, |
| wolfSSL | 4:1b0d80432c79 | 49 | 0xd6, 0x9c, 0xf7, 0xa2, 0xde, 0xf9, 0xde, 0x14, |
| wolfSSL | 4:1b0d80432c79 | 50 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| wolfSSL | 4:1b0d80432c79 | 51 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10 |
| wolfSSL | 4:1b0d80432c79 | 52 | }; |
| wolfSSL | 4:1b0d80432c79 | 53 | |
| wolfSSL | 4:1b0d80432c79 | 54 | /*Arithmetic modulo the group order m = 2^252 + |
| wolfSSL | 4:1b0d80432c79 | 55 | 27742317777372353535851937790883648493 = |
| wolfSSL | 4:1b0d80432c79 | 56 | 7237005577332262213973186563042994240857116359379907606001950938285454250989 */ |
| wolfSSL | 4:1b0d80432c79 | 57 | |
| wolfSSL | 4:1b0d80432c79 | 58 | static const word32 m[32] = { |
| wolfSSL | 4:1b0d80432c79 | 59 | 0xED,0xD3,0xF5,0x5C,0x1A,0x63,0x12,0x58,0xD6,0x9C,0xF7,0xA2,0xDE,0xF9, |
| wolfSSL | 4:1b0d80432c79 | 60 | 0xDE,0x14,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, |
| wolfSSL | 4:1b0d80432c79 | 61 | 0x00,0x00,0x00,0x10 |
| wolfSSL | 4:1b0d80432c79 | 62 | }; |
| wolfSSL | 4:1b0d80432c79 | 63 | |
| wolfSSL | 4:1b0d80432c79 | 64 | static const word32 mu[33] = { |
| wolfSSL | 4:1b0d80432c79 | 65 | 0x1B,0x13,0x2C,0x0A,0xA3,0xE5,0x9C,0xED,0xA7,0x29,0x63,0x08,0x5D,0x21, |
| wolfSSL | 4:1b0d80432c79 | 66 | 0x06,0x21,0xEB,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, |
| wolfSSL | 4:1b0d80432c79 | 67 | 0xFF,0xFF,0xFF,0xFF,0x0F |
| wolfSSL | 4:1b0d80432c79 | 68 | }; |
| wolfSSL | 4:1b0d80432c79 | 69 | |
| wolfSSL | 4:1b0d80432c79 | 70 | |
| wolfSSL | 4:1b0d80432c79 | 71 | int ge_compress_key(byte* out, const byte* xIn, const byte* yIn, |
| wolfSSL | 4:1b0d80432c79 | 72 | word32 keySz) |
| wolfSSL | 4:1b0d80432c79 | 73 | { |
| wolfSSL | 4:1b0d80432c79 | 74 | byte tmp[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 75 | byte parity; |
| wolfSSL | 4:1b0d80432c79 | 76 | byte pt[32]; |
| wolfSSL | 4:1b0d80432c79 | 77 | int i; |
| wolfSSL | 4:1b0d80432c79 | 78 | |
| wolfSSL | 4:1b0d80432c79 | 79 | fe_copy(tmp, xIn); |
| wolfSSL | 4:1b0d80432c79 | 80 | parity = (tmp[0] & 1) << 7; |
| wolfSSL | 4:1b0d80432c79 | 81 | |
| wolfSSL | 4:1b0d80432c79 | 82 | fe_copy(pt, yIn); |
| wolfSSL | 4:1b0d80432c79 | 83 | pt[31] |= parity; |
| wolfSSL | 4:1b0d80432c79 | 84 | |
| wolfSSL | 4:1b0d80432c79 | 85 | for(i = 0; i < 32; i++) { |
| wolfSSL | 4:1b0d80432c79 | 86 | out[32-i-1] = pt[i]; |
| wolfSSL | 4:1b0d80432c79 | 87 | } |
| wolfSSL | 4:1b0d80432c79 | 88 | (void)keySz; |
| wolfSSL | 4:1b0d80432c79 | 89 | return 0; |
| wolfSSL | 4:1b0d80432c79 | 90 | } |
| wolfSSL | 4:1b0d80432c79 | 91 | |
| wolfSSL | 4:1b0d80432c79 | 92 | |
| wolfSSL | 4:1b0d80432c79 | 93 | static word32 lt(word32 a,word32 b) /* 16-bit inputs */ |
| wolfSSL | 4:1b0d80432c79 | 94 | { |
| wolfSSL | 4:1b0d80432c79 | 95 | unsigned int x = a; |
| wolfSSL | 4:1b0d80432c79 | 96 | x -= (unsigned int) b; /* 0..65535: no; 4294901761..4294967295: yes */ |
| wolfSSL | 4:1b0d80432c79 | 97 | x >>= 31; /* 0: no; 1: yes */ |
| wolfSSL | 4:1b0d80432c79 | 98 | return x; |
| wolfSSL | 4:1b0d80432c79 | 99 | } |
| wolfSSL | 4:1b0d80432c79 | 100 | |
| wolfSSL | 4:1b0d80432c79 | 101 | |
| wolfSSL | 4:1b0d80432c79 | 102 | /* Reduce coefficients of r before calling reduce_add_sub */ |
| wolfSSL | 4:1b0d80432c79 | 103 | static void reduce_add_sub(word32 *r) |
| wolfSSL | 4:1b0d80432c79 | 104 | { |
| wolfSSL | 4:1b0d80432c79 | 105 | word32 pb = 0; |
| wolfSSL | 4:1b0d80432c79 | 106 | word32 b; |
| wolfSSL | 4:1b0d80432c79 | 107 | word32 mask; |
| wolfSSL | 4:1b0d80432c79 | 108 | int i; |
| wolfSSL | 4:1b0d80432c79 | 109 | unsigned char t[32]; |
| wolfSSL | 4:1b0d80432c79 | 110 | |
| wolfSSL | 4:1b0d80432c79 | 111 | for(i=0;i<32;i++) |
| wolfSSL | 4:1b0d80432c79 | 112 | { |
| wolfSSL | 4:1b0d80432c79 | 113 | pb += m[i]; |
| wolfSSL | 4:1b0d80432c79 | 114 | b = lt(r[i],pb); |
| wolfSSL | 4:1b0d80432c79 | 115 | t[i] = r[i]-pb+(b<<8); |
| wolfSSL | 4:1b0d80432c79 | 116 | pb = b; |
| wolfSSL | 4:1b0d80432c79 | 117 | } |
| wolfSSL | 4:1b0d80432c79 | 118 | mask = b - 1; |
| wolfSSL | 4:1b0d80432c79 | 119 | for(i=0;i<32;i++) |
| wolfSSL | 4:1b0d80432c79 | 120 | r[i] ^= mask & (r[i] ^ t[i]); |
| wolfSSL | 4:1b0d80432c79 | 121 | } |
| wolfSSL | 4:1b0d80432c79 | 122 | |
| wolfSSL | 4:1b0d80432c79 | 123 | |
| wolfSSL | 4:1b0d80432c79 | 124 | /* Reduce coefficients of x before calling barrett_reduce */ |
| wolfSSL | 4:1b0d80432c79 | 125 | static void barrett_reduce(word32* r, word32 x[64]) |
| wolfSSL | 4:1b0d80432c79 | 126 | { |
| wolfSSL | 4:1b0d80432c79 | 127 | /* See HAC, Alg. 14.42 */ |
| wolfSSL | 4:1b0d80432c79 | 128 | int i,j; |
| wolfSSL | 4:1b0d80432c79 | 129 | word32 q2[66]; |
| wolfSSL | 4:1b0d80432c79 | 130 | word32 *q3 = q2 + 33; |
| wolfSSL | 4:1b0d80432c79 | 131 | word32 r1[33]; |
| wolfSSL | 4:1b0d80432c79 | 132 | word32 r2[33]; |
| wolfSSL | 4:1b0d80432c79 | 133 | word32 carry; |
| wolfSSL | 4:1b0d80432c79 | 134 | word32 pb = 0; |
| wolfSSL | 4:1b0d80432c79 | 135 | word32 b; |
| wolfSSL | 4:1b0d80432c79 | 136 | |
| wolfSSL | 4:1b0d80432c79 | 137 | for (i = 0;i < 66;++i) q2[i] = 0; |
| wolfSSL | 4:1b0d80432c79 | 138 | for (i = 0;i < 33;++i) r2[i] = 0; |
| wolfSSL | 4:1b0d80432c79 | 139 | |
| wolfSSL | 4:1b0d80432c79 | 140 | for(i=0;i<33;i++) |
| wolfSSL | 4:1b0d80432c79 | 141 | for(j=0;j<33;j++) |
| wolfSSL | 4:1b0d80432c79 | 142 | if(i+j >= 31) q2[i+j] += mu[i]*x[j+31]; |
| wolfSSL | 4:1b0d80432c79 | 143 | carry = q2[31] >> 8; |
| wolfSSL | 4:1b0d80432c79 | 144 | q2[32] += carry; |
| wolfSSL | 4:1b0d80432c79 | 145 | carry = q2[32] >> 8; |
| wolfSSL | 4:1b0d80432c79 | 146 | q2[33] += carry; |
| wolfSSL | 4:1b0d80432c79 | 147 | |
| wolfSSL | 4:1b0d80432c79 | 148 | for(i=0;i<33;i++)r1[i] = x[i]; |
| wolfSSL | 4:1b0d80432c79 | 149 | for(i=0;i<32;i++) |
| wolfSSL | 4:1b0d80432c79 | 150 | for(j=0;j<33;j++) |
| wolfSSL | 4:1b0d80432c79 | 151 | if(i+j < 33) r2[i+j] += m[i]*q3[j]; |
| wolfSSL | 4:1b0d80432c79 | 152 | |
| wolfSSL | 4:1b0d80432c79 | 153 | for(i=0;i<32;i++) |
| wolfSSL | 4:1b0d80432c79 | 154 | { |
| wolfSSL | 4:1b0d80432c79 | 155 | carry = r2[i] >> 8; |
| wolfSSL | 4:1b0d80432c79 | 156 | r2[i+1] += carry; |
| wolfSSL | 4:1b0d80432c79 | 157 | r2[i] &= 0xff; |
| wolfSSL | 4:1b0d80432c79 | 158 | } |
| wolfSSL | 4:1b0d80432c79 | 159 | |
| wolfSSL | 4:1b0d80432c79 | 160 | for(i=0;i<32;i++) |
| wolfSSL | 4:1b0d80432c79 | 161 | { |
| wolfSSL | 4:1b0d80432c79 | 162 | pb += r2[i]; |
| wolfSSL | 4:1b0d80432c79 | 163 | b = lt(r1[i],pb); |
| wolfSSL | 4:1b0d80432c79 | 164 | r[i] = r1[i]-pb+(b<<8); |
| wolfSSL | 4:1b0d80432c79 | 165 | pb = b; |
| wolfSSL | 4:1b0d80432c79 | 166 | } |
| wolfSSL | 4:1b0d80432c79 | 167 | |
| wolfSSL | 4:1b0d80432c79 | 168 | /* XXX: Can it really happen that r<0?, See HAC, Alg 14.42, Step 3 |
| wolfSSL | 4:1b0d80432c79 | 169 | * r is an unsigned type. |
| wolfSSL | 4:1b0d80432c79 | 170 | * If so: Handle it here! |
| wolfSSL | 4:1b0d80432c79 | 171 | */ |
| wolfSSL | 4:1b0d80432c79 | 172 | |
| wolfSSL | 4:1b0d80432c79 | 173 | reduce_add_sub(r); |
| wolfSSL | 4:1b0d80432c79 | 174 | reduce_add_sub(r); |
| wolfSSL | 4:1b0d80432c79 | 175 | } |
| wolfSSL | 4:1b0d80432c79 | 176 | |
| wolfSSL | 4:1b0d80432c79 | 177 | |
| wolfSSL | 4:1b0d80432c79 | 178 | void sc_reduce(unsigned char x[64]) |
| wolfSSL | 4:1b0d80432c79 | 179 | { |
| wolfSSL | 4:1b0d80432c79 | 180 | int i; |
| wolfSSL | 4:1b0d80432c79 | 181 | word32 t[64]; |
| wolfSSL | 4:1b0d80432c79 | 182 | word32 r[32]; |
| wolfSSL | 4:1b0d80432c79 | 183 | for(i=0;i<64;i++) t[i] = x[i]; |
| wolfSSL | 4:1b0d80432c79 | 184 | barrett_reduce(r, t); |
| wolfSSL | 4:1b0d80432c79 | 185 | for(i=0;i<32;i++) x[i] = (r[i] & 0xFF); |
| wolfSSL | 4:1b0d80432c79 | 186 | } |
| wolfSSL | 4:1b0d80432c79 | 187 | |
| wolfSSL | 4:1b0d80432c79 | 188 | |
| wolfSSL | 4:1b0d80432c79 | 189 | void sc_muladd(byte* out, const byte* a, const byte* b, const byte* c) |
| wolfSSL | 4:1b0d80432c79 | 190 | { |
| wolfSSL | 4:1b0d80432c79 | 191 | |
| wolfSSL | 4:1b0d80432c79 | 192 | byte s[32]; |
| wolfSSL | 4:1b0d80432c79 | 193 | byte e[64]; |
| wolfSSL | 4:1b0d80432c79 | 194 | |
| wolfSSL | 4:1b0d80432c79 | 195 | XMEMSET(e, 0, sizeof(e)); |
| wolfSSL | 4:1b0d80432c79 | 196 | XMEMCPY(e, b, 32); |
| wolfSSL | 4:1b0d80432c79 | 197 | |
| wolfSSL | 4:1b0d80432c79 | 198 | /* Obtain e */ |
| wolfSSL | 4:1b0d80432c79 | 199 | sc_reduce(e); |
| wolfSSL | 4:1b0d80432c79 | 200 | |
| wolfSSL | 4:1b0d80432c79 | 201 | /* Compute s = ze + k */ |
| wolfSSL | 4:1b0d80432c79 | 202 | fprime_mul(s, a, e, ed25519_order); |
| wolfSSL | 4:1b0d80432c79 | 203 | fprime_add(s, c, ed25519_order); |
| wolfSSL | 4:1b0d80432c79 | 204 | |
| wolfSSL | 4:1b0d80432c79 | 205 | XMEMCPY(out, s, 32); |
| wolfSSL | 4:1b0d80432c79 | 206 | } |
| wolfSSL | 4:1b0d80432c79 | 207 | |
| wolfSSL | 4:1b0d80432c79 | 208 | |
| wolfSSL | 4:1b0d80432c79 | 209 | /* Base point is (numbers wrapped): |
| wolfSSL | 4:1b0d80432c79 | 210 | * |
| wolfSSL | 4:1b0d80432c79 | 211 | * x = 151122213495354007725011514095885315114 |
| wolfSSL | 4:1b0d80432c79 | 212 | * 54012693041857206046113283949847762202 |
| wolfSSL | 4:1b0d80432c79 | 213 | * y = 463168356949264781694283940034751631413 |
| wolfSSL | 4:1b0d80432c79 | 214 | * 07993866256225615783033603165251855960 |
| wolfSSL | 4:1b0d80432c79 | 215 | * |
| wolfSSL | 4:1b0d80432c79 | 216 | * y is derived by transforming the original Montgomery base (u=9). x |
| wolfSSL | 4:1b0d80432c79 | 217 | * is the corresponding positive coordinate for the new curve equation. |
| wolfSSL | 4:1b0d80432c79 | 218 | * t is x*y. |
| wolfSSL | 4:1b0d80432c79 | 219 | */ |
| wolfSSL | 4:1b0d80432c79 | 220 | const ge_p3 ed25519_base = { |
| wolfSSL | 4:1b0d80432c79 | 221 | { |
| wolfSSL | 4:1b0d80432c79 | 222 | 0x1a, 0xd5, 0x25, 0x8f, 0x60, 0x2d, 0x56, 0xc9, |
| wolfSSL | 4:1b0d80432c79 | 223 | 0xb2, 0xa7, 0x25, 0x95, 0x60, 0xc7, 0x2c, 0x69, |
| wolfSSL | 4:1b0d80432c79 | 224 | 0x5c, 0xdc, 0xd6, 0xfd, 0x31, 0xe2, 0xa4, 0xc0, |
| wolfSSL | 4:1b0d80432c79 | 225 | 0xfe, 0x53, 0x6e, 0xcd, 0xd3, 0x36, 0x69, 0x21 |
| wolfSSL | 4:1b0d80432c79 | 226 | }, |
| wolfSSL | 4:1b0d80432c79 | 227 | { |
| wolfSSL | 4:1b0d80432c79 | 228 | 0x58, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, |
| wolfSSL | 4:1b0d80432c79 | 229 | 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, |
| wolfSSL | 4:1b0d80432c79 | 230 | 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, |
| wolfSSL | 4:1b0d80432c79 | 231 | 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66 |
| wolfSSL | 4:1b0d80432c79 | 232 | }, |
| wolfSSL | 4:1b0d80432c79 | 233 | {1, 0}, |
| wolfSSL | 4:1b0d80432c79 | 234 | { |
| wolfSSL | 4:1b0d80432c79 | 235 | 0xa3, 0xdd, 0xb7, 0xa5, 0xb3, 0x8a, 0xde, 0x6d, |
| wolfSSL | 4:1b0d80432c79 | 236 | 0xf5, 0x52, 0x51, 0x77, 0x80, 0x9f, 0xf0, 0x20, |
| wolfSSL | 4:1b0d80432c79 | 237 | 0x7d, 0xe3, 0xab, 0x64, 0x8e, 0x4e, 0xea, 0x66, |
| wolfSSL | 4:1b0d80432c79 | 238 | 0x65, 0x76, 0x8b, 0xd7, 0x0f, 0x5f, 0x87, 0x67 |
| wolfSSL | 4:1b0d80432c79 | 239 | }, |
| wolfSSL | 4:1b0d80432c79 | 240 | |
| wolfSSL | 4:1b0d80432c79 | 241 | }; |
| wolfSSL | 4:1b0d80432c79 | 242 | |
| wolfSSL | 4:1b0d80432c79 | 243 | |
| wolfSSL | 4:1b0d80432c79 | 244 | const ge_p3 ed25519_neutral = { |
| wolfSSL | 4:1b0d80432c79 | 245 | {0}, |
| wolfSSL | 4:1b0d80432c79 | 246 | {1, 0}, |
| wolfSSL | 4:1b0d80432c79 | 247 | {1, 0}, |
| wolfSSL | 4:1b0d80432c79 | 248 | {0}, |
| wolfSSL | 4:1b0d80432c79 | 249 | |
| wolfSSL | 4:1b0d80432c79 | 250 | }; |
| wolfSSL | 4:1b0d80432c79 | 251 | |
| wolfSSL | 4:1b0d80432c79 | 252 | |
| wolfSSL | 4:1b0d80432c79 | 253 | static const byte ed25519_d[F25519_SIZE] = { |
| wolfSSL | 4:1b0d80432c79 | 254 | 0xa3, 0x78, 0x59, 0x13, 0xca, 0x4d, 0xeb, 0x75, |
| wolfSSL | 4:1b0d80432c79 | 255 | 0xab, 0xd8, 0x41, 0x41, 0x4d, 0x0a, 0x70, 0x00, |
| wolfSSL | 4:1b0d80432c79 | 256 | 0x98, 0xe8, 0x79, 0x77, 0x79, 0x40, 0xc7, 0x8c, |
| wolfSSL | 4:1b0d80432c79 | 257 | 0x73, 0xfe, 0x6f, 0x2b, 0xee, 0x6c, 0x03, 0x52 |
| wolfSSL | 4:1b0d80432c79 | 258 | }; |
| wolfSSL | 4:1b0d80432c79 | 259 | |
| wolfSSL | 4:1b0d80432c79 | 260 | |
| wolfSSL | 4:1b0d80432c79 | 261 | /* k = 2d */ |
| wolfSSL | 4:1b0d80432c79 | 262 | static const byte ed25519_k[F25519_SIZE] = { |
| wolfSSL | 4:1b0d80432c79 | 263 | 0x59, 0xf1, 0xb2, 0x26, 0x94, 0x9b, 0xd6, 0xeb, |
| wolfSSL | 4:1b0d80432c79 | 264 | 0x56, 0xb1, 0x83, 0x82, 0x9a, 0x14, 0xe0, 0x00, |
| wolfSSL | 4:1b0d80432c79 | 265 | 0x30, 0xd1, 0xf3, 0xee, 0xf2, 0x80, 0x8e, 0x19, |
| wolfSSL | 4:1b0d80432c79 | 266 | 0xe7, 0xfc, 0xdf, 0x56, 0xdc, 0xd9, 0x06, 0x24 |
| wolfSSL | 4:1b0d80432c79 | 267 | }; |
| wolfSSL | 4:1b0d80432c79 | 268 | |
| wolfSSL | 4:1b0d80432c79 | 269 | |
| wolfSSL | 4:1b0d80432c79 | 270 | void ed25519_add(ge_p3 *r, |
| wolfSSL | 4:1b0d80432c79 | 271 | const ge_p3 *p1, const ge_p3 *p2) |
| wolfSSL | 4:1b0d80432c79 | 272 | { |
| wolfSSL | 4:1b0d80432c79 | 273 | /* Explicit formulas database: add-2008-hwcd-3 |
| wolfSSL | 4:1b0d80432c79 | 274 | * |
| wolfSSL | 4:1b0d80432c79 | 275 | * source 2008 Hisil--Wong--Carter--Dawson, |
| wolfSSL | 4:1b0d80432c79 | 276 | * http://eprint.iacr.org/2008/522, Section 3.1 |
| wolfSSL | 4:1b0d80432c79 | 277 | * appliesto extended-1 |
| wolfSSL | 4:1b0d80432c79 | 278 | * parameter k |
| wolfSSL | 4:1b0d80432c79 | 279 | * assume k = 2 d |
| wolfSSL | 4:1b0d80432c79 | 280 | * compute A = (Y1-X1)(Y2-X2) |
| wolfSSL | 4:1b0d80432c79 | 281 | * compute B = (Y1+X1)(Y2+X2) |
| wolfSSL | 4:1b0d80432c79 | 282 | * compute C = T1 k T2 |
| wolfSSL | 4:1b0d80432c79 | 283 | * compute D = Z1 2 Z2 |
| wolfSSL | 4:1b0d80432c79 | 284 | * compute E = B - A |
| wolfSSL | 4:1b0d80432c79 | 285 | * compute F = D - C |
| wolfSSL | 4:1b0d80432c79 | 286 | * compute G = D + C |
| wolfSSL | 4:1b0d80432c79 | 287 | * compute H = B + A |
| wolfSSL | 4:1b0d80432c79 | 288 | * compute X3 = E F |
| wolfSSL | 4:1b0d80432c79 | 289 | * compute Y3 = G H |
| wolfSSL | 4:1b0d80432c79 | 290 | * compute T3 = E H |
| wolfSSL | 4:1b0d80432c79 | 291 | * compute Z3 = F G |
| wolfSSL | 4:1b0d80432c79 | 292 | */ |
| wolfSSL | 4:1b0d80432c79 | 293 | byte a[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 294 | byte b[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 295 | byte c[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 296 | byte d[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 297 | byte e[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 298 | byte f[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 299 | byte g[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 300 | byte h[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 301 | |
| wolfSSL | 4:1b0d80432c79 | 302 | /* A = (Y1-X1)(Y2-X2) */ |
| wolfSSL | 4:1b0d80432c79 | 303 | fe_sub(c, p1->Y, p1->X); |
| wolfSSL | 4:1b0d80432c79 | 304 | fe_sub(d, p2->Y, p2->X); |
| wolfSSL | 4:1b0d80432c79 | 305 | fe_mul__distinct(a, c, d); |
| wolfSSL | 4:1b0d80432c79 | 306 | |
| wolfSSL | 4:1b0d80432c79 | 307 | /* B = (Y1+X1)(Y2+X2) */ |
| wolfSSL | 4:1b0d80432c79 | 308 | fe_add(c, p1->Y, p1->X); |
| wolfSSL | 4:1b0d80432c79 | 309 | fe_add(d, p2->Y, p2->X); |
| wolfSSL | 4:1b0d80432c79 | 310 | fe_mul__distinct(b, c, d); |
| wolfSSL | 4:1b0d80432c79 | 311 | |
| wolfSSL | 4:1b0d80432c79 | 312 | /* C = T1 k T2 */ |
| wolfSSL | 4:1b0d80432c79 | 313 | fe_mul__distinct(d, p1->T, p2->T); |
| wolfSSL | 4:1b0d80432c79 | 314 | fe_mul__distinct(c, d, ed25519_k); |
| wolfSSL | 4:1b0d80432c79 | 315 | |
| wolfSSL | 4:1b0d80432c79 | 316 | /* D = Z1 2 Z2 */ |
| wolfSSL | 4:1b0d80432c79 | 317 | fe_mul__distinct(d, p1->Z, p2->Z); |
| wolfSSL | 4:1b0d80432c79 | 318 | fe_add(d, d, d); |
| wolfSSL | 4:1b0d80432c79 | 319 | |
| wolfSSL | 4:1b0d80432c79 | 320 | /* E = B - A */ |
| wolfSSL | 4:1b0d80432c79 | 321 | fe_sub(e, b, a); |
| wolfSSL | 4:1b0d80432c79 | 322 | |
| wolfSSL | 4:1b0d80432c79 | 323 | /* F = D - C */ |
| wolfSSL | 4:1b0d80432c79 | 324 | fe_sub(f, d, c); |
| wolfSSL | 4:1b0d80432c79 | 325 | |
| wolfSSL | 4:1b0d80432c79 | 326 | /* G = D + C */ |
| wolfSSL | 4:1b0d80432c79 | 327 | fe_add(g, d, c); |
| wolfSSL | 4:1b0d80432c79 | 328 | |
| wolfSSL | 4:1b0d80432c79 | 329 | /* H = B + A */ |
| wolfSSL | 4:1b0d80432c79 | 330 | fe_add(h, b, a); |
| wolfSSL | 4:1b0d80432c79 | 331 | |
| wolfSSL | 4:1b0d80432c79 | 332 | /* X3 = E F */ |
| wolfSSL | 4:1b0d80432c79 | 333 | fe_mul__distinct(r->X, e, f); |
| wolfSSL | 4:1b0d80432c79 | 334 | |
| wolfSSL | 4:1b0d80432c79 | 335 | /* Y3 = G H */ |
| wolfSSL | 4:1b0d80432c79 | 336 | fe_mul__distinct(r->Y, g, h); |
| wolfSSL | 4:1b0d80432c79 | 337 | |
| wolfSSL | 4:1b0d80432c79 | 338 | /* T3 = E H */ |
| wolfSSL | 4:1b0d80432c79 | 339 | fe_mul__distinct(r->T, e, h); |
| wolfSSL | 4:1b0d80432c79 | 340 | |
| wolfSSL | 4:1b0d80432c79 | 341 | /* Z3 = F G */ |
| wolfSSL | 4:1b0d80432c79 | 342 | fe_mul__distinct(r->Z, f, g); |
| wolfSSL | 4:1b0d80432c79 | 343 | } |
| wolfSSL | 4:1b0d80432c79 | 344 | |
| wolfSSL | 4:1b0d80432c79 | 345 | |
| wolfSSL | 4:1b0d80432c79 | 346 | void ed25519_double(ge_p3 *r, const ge_p3 *p) |
| wolfSSL | 4:1b0d80432c79 | 347 | { |
| wolfSSL | 4:1b0d80432c79 | 348 | /* Explicit formulas database: dbl-2008-hwcd |
| wolfSSL | 4:1b0d80432c79 | 349 | * |
| wolfSSL | 4:1b0d80432c79 | 350 | * source 2008 Hisil--Wong--Carter--Dawson, |
| wolfSSL | 4:1b0d80432c79 | 351 | * http://eprint.iacr.org/2008/522, Section 3.3 |
| wolfSSL | 4:1b0d80432c79 | 352 | * compute A = X1^2 |
| wolfSSL | 4:1b0d80432c79 | 353 | * compute B = Y1^2 |
| wolfSSL | 4:1b0d80432c79 | 354 | * compute C = 2 Z1^2 |
| wolfSSL | 4:1b0d80432c79 | 355 | * compute D = a A |
| wolfSSL | 4:1b0d80432c79 | 356 | * compute E = (X1+Y1)^2-A-B |
| wolfSSL | 4:1b0d80432c79 | 357 | * compute G = D + B |
| wolfSSL | 4:1b0d80432c79 | 358 | * compute F = G - C |
| wolfSSL | 4:1b0d80432c79 | 359 | * compute H = D - B |
| wolfSSL | 4:1b0d80432c79 | 360 | * compute X3 = E F |
| wolfSSL | 4:1b0d80432c79 | 361 | * compute Y3 = G H |
| wolfSSL | 4:1b0d80432c79 | 362 | * compute T3 = E H |
| wolfSSL | 4:1b0d80432c79 | 363 | * compute Z3 = F G |
| wolfSSL | 4:1b0d80432c79 | 364 | */ |
| wolfSSL | 4:1b0d80432c79 | 365 | byte a[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 366 | byte b[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 367 | byte c[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 368 | byte e[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 369 | byte f[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 370 | byte g[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 371 | byte h[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 372 | |
| wolfSSL | 4:1b0d80432c79 | 373 | /* A = X1^2 */ |
| wolfSSL | 4:1b0d80432c79 | 374 | fe_mul__distinct(a, p->X, p->X); |
| wolfSSL | 4:1b0d80432c79 | 375 | |
| wolfSSL | 4:1b0d80432c79 | 376 | /* B = Y1^2 */ |
| wolfSSL | 4:1b0d80432c79 | 377 | fe_mul__distinct(b, p->Y, p->Y); |
| wolfSSL | 4:1b0d80432c79 | 378 | |
| wolfSSL | 4:1b0d80432c79 | 379 | /* C = 2 Z1^2 */ |
| wolfSSL | 4:1b0d80432c79 | 380 | fe_mul__distinct(c, p->Z, p->Z); |
| wolfSSL | 4:1b0d80432c79 | 381 | fe_add(c, c, c); |
| wolfSSL | 4:1b0d80432c79 | 382 | |
| wolfSSL | 4:1b0d80432c79 | 383 | /* D = a A (alter sign) */ |
| wolfSSL | 4:1b0d80432c79 | 384 | /* E = (X1+Y1)^2-A-B */ |
| wolfSSL | 4:1b0d80432c79 | 385 | fe_add(f, p->X, p->Y); |
| wolfSSL | 4:1b0d80432c79 | 386 | fe_mul__distinct(e, f, f); |
| wolfSSL | 4:1b0d80432c79 | 387 | fe_sub(e, e, a); |
| wolfSSL | 4:1b0d80432c79 | 388 | fe_sub(e, e, b); |
| wolfSSL | 4:1b0d80432c79 | 389 | |
| wolfSSL | 4:1b0d80432c79 | 390 | /* G = D + B */ |
| wolfSSL | 4:1b0d80432c79 | 391 | fe_sub(g, b, a); |
| wolfSSL | 4:1b0d80432c79 | 392 | |
| wolfSSL | 4:1b0d80432c79 | 393 | /* F = G - C */ |
| wolfSSL | 4:1b0d80432c79 | 394 | fe_sub(f, g, c); |
| wolfSSL | 4:1b0d80432c79 | 395 | |
| wolfSSL | 4:1b0d80432c79 | 396 | /* H = D - B */ |
| wolfSSL | 4:1b0d80432c79 | 397 | fe_neg(h, b); |
| wolfSSL | 4:1b0d80432c79 | 398 | fe_sub(h, h, a); |
| wolfSSL | 4:1b0d80432c79 | 399 | |
| wolfSSL | 4:1b0d80432c79 | 400 | /* X3 = E F */ |
| wolfSSL | 4:1b0d80432c79 | 401 | fe_mul__distinct(r->X, e, f); |
| wolfSSL | 4:1b0d80432c79 | 402 | |
| wolfSSL | 4:1b0d80432c79 | 403 | /* Y3 = G H */ |
| wolfSSL | 4:1b0d80432c79 | 404 | fe_mul__distinct(r->Y, g, h); |
| wolfSSL | 4:1b0d80432c79 | 405 | |
| wolfSSL | 4:1b0d80432c79 | 406 | /* T3 = E H */ |
| wolfSSL | 4:1b0d80432c79 | 407 | fe_mul__distinct(r->T, e, h); |
| wolfSSL | 4:1b0d80432c79 | 408 | |
| wolfSSL | 4:1b0d80432c79 | 409 | /* Z3 = F G */ |
| wolfSSL | 4:1b0d80432c79 | 410 | fe_mul__distinct(r->Z, f, g); |
| wolfSSL | 4:1b0d80432c79 | 411 | } |
| wolfSSL | 4:1b0d80432c79 | 412 | |
| wolfSSL | 4:1b0d80432c79 | 413 | |
| wolfSSL | 4:1b0d80432c79 | 414 | void ed25519_smult(ge_p3 *r_out, const ge_p3 *p, const byte *e) |
| wolfSSL | 4:1b0d80432c79 | 415 | { |
| wolfSSL | 4:1b0d80432c79 | 416 | ge_p3 r; |
| wolfSSL | 4:1b0d80432c79 | 417 | int i; |
| wolfSSL | 4:1b0d80432c79 | 418 | |
| wolfSSL | 4:1b0d80432c79 | 419 | XMEMCPY(&r, &ed25519_neutral, sizeof(r)); |
| wolfSSL | 4:1b0d80432c79 | 420 | |
| wolfSSL | 4:1b0d80432c79 | 421 | for (i = 255; i >= 0; i--) { |
| wolfSSL | 4:1b0d80432c79 | 422 | const byte bit = (e[i >> 3] >> (i & 7)) & 1; |
| wolfSSL | 4:1b0d80432c79 | 423 | ge_p3 s; |
| wolfSSL | 4:1b0d80432c79 | 424 | |
| wolfSSL | 4:1b0d80432c79 | 425 | ed25519_double(&r, &r); |
| wolfSSL | 4:1b0d80432c79 | 426 | ed25519_add(&s, &r, p); |
| wolfSSL | 4:1b0d80432c79 | 427 | |
| wolfSSL | 4:1b0d80432c79 | 428 | fe_select(r.X, r.X, s.X, bit); |
| wolfSSL | 4:1b0d80432c79 | 429 | fe_select(r.Y, r.Y, s.Y, bit); |
| wolfSSL | 4:1b0d80432c79 | 430 | fe_select(r.Z, r.Z, s.Z, bit); |
| wolfSSL | 4:1b0d80432c79 | 431 | fe_select(r.T, r.T, s.T, bit); |
| wolfSSL | 4:1b0d80432c79 | 432 | } |
| wolfSSL | 4:1b0d80432c79 | 433 | XMEMCPY(r_out, &r, sizeof(r)); |
| wolfSSL | 4:1b0d80432c79 | 434 | } |
| wolfSSL | 4:1b0d80432c79 | 435 | |
| wolfSSL | 4:1b0d80432c79 | 436 | |
| wolfSSL | 4:1b0d80432c79 | 437 | void ge_scalarmult_base(ge_p3 *R,const unsigned char *nonce) |
| wolfSSL | 4:1b0d80432c79 | 438 | { |
| wolfSSL | 4:1b0d80432c79 | 439 | ed25519_smult(R, &ed25519_base, nonce); |
| wolfSSL | 4:1b0d80432c79 | 440 | } |
| wolfSSL | 4:1b0d80432c79 | 441 | |
| wolfSSL | 4:1b0d80432c79 | 442 | |
| wolfSSL | 4:1b0d80432c79 | 443 | /* pack the point h into array s */ |
| wolfSSL | 4:1b0d80432c79 | 444 | void ge_p3_tobytes(unsigned char *s,const ge_p3 *h) |
| wolfSSL | 4:1b0d80432c79 | 445 | { |
| wolfSSL | 4:1b0d80432c79 | 446 | byte x[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 447 | byte y[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 448 | byte z1[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 449 | byte parity; |
| wolfSSL | 4:1b0d80432c79 | 450 | |
| wolfSSL | 4:1b0d80432c79 | 451 | fe_inv__distinct(z1, h->Z); |
| wolfSSL | 4:1b0d80432c79 | 452 | fe_mul__distinct(x, h->X, z1); |
| wolfSSL | 4:1b0d80432c79 | 453 | fe_mul__distinct(y, h->Y, z1); |
| wolfSSL | 4:1b0d80432c79 | 454 | |
| wolfSSL | 4:1b0d80432c79 | 455 | fe_normalize(x); |
| wolfSSL | 4:1b0d80432c79 | 456 | fe_normalize(y); |
| wolfSSL | 4:1b0d80432c79 | 457 | |
| wolfSSL | 4:1b0d80432c79 | 458 | parity = (x[0] & 1) << 7; |
| wolfSSL | 4:1b0d80432c79 | 459 | fe_copy(s, y); |
| wolfSSL | 4:1b0d80432c79 | 460 | fe_normalize(s); |
| wolfSSL | 4:1b0d80432c79 | 461 | s[31] |= parity; |
| wolfSSL | 4:1b0d80432c79 | 462 | } |
| wolfSSL | 4:1b0d80432c79 | 463 | |
| wolfSSL | 4:1b0d80432c79 | 464 | |
| wolfSSL | 4:1b0d80432c79 | 465 | /* pack the point h into array s */ |
| wolfSSL | 4:1b0d80432c79 | 466 | void ge_tobytes(unsigned char *s,const ge_p2 *h) |
| wolfSSL | 4:1b0d80432c79 | 467 | { |
| wolfSSL | 4:1b0d80432c79 | 468 | byte x[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 469 | byte y[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 470 | byte z1[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 471 | byte parity; |
| wolfSSL | 4:1b0d80432c79 | 472 | |
| wolfSSL | 4:1b0d80432c79 | 473 | fe_inv__distinct(z1, h->Z); |
| wolfSSL | 4:1b0d80432c79 | 474 | fe_mul__distinct(x, h->X, z1); |
| wolfSSL | 4:1b0d80432c79 | 475 | fe_mul__distinct(y, h->Y, z1); |
| wolfSSL | 4:1b0d80432c79 | 476 | |
| wolfSSL | 4:1b0d80432c79 | 477 | fe_normalize(x); |
| wolfSSL | 4:1b0d80432c79 | 478 | fe_normalize(y); |
| wolfSSL | 4:1b0d80432c79 | 479 | |
| wolfSSL | 4:1b0d80432c79 | 480 | parity = (x[0] & 1) << 7; |
| wolfSSL | 4:1b0d80432c79 | 481 | fe_copy(s, y); |
| wolfSSL | 4:1b0d80432c79 | 482 | fe_normalize(s); |
| wolfSSL | 4:1b0d80432c79 | 483 | s[31] |= parity; |
| wolfSSL | 4:1b0d80432c79 | 484 | } |
| wolfSSL | 4:1b0d80432c79 | 485 | |
| wolfSSL | 4:1b0d80432c79 | 486 | |
| wolfSSL | 4:1b0d80432c79 | 487 | /* |
| wolfSSL | 4:1b0d80432c79 | 488 | Test if the public key can be uncompressed and negate it (-X,Y,Z,-T) |
| wolfSSL | 4:1b0d80432c79 | 489 | return 0 on success |
| wolfSSL | 4:1b0d80432c79 | 490 | */ |
| wolfSSL | 4:1b0d80432c79 | 491 | int ge_frombytes_negate_vartime(ge_p3 *p,const unsigned char *s) |
| wolfSSL | 4:1b0d80432c79 | 492 | { |
| wolfSSL | 4:1b0d80432c79 | 493 | |
| wolfSSL | 4:1b0d80432c79 | 494 | byte parity; |
| wolfSSL | 4:1b0d80432c79 | 495 | byte x[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 496 | byte y[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 497 | byte a[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 498 | byte b[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 499 | byte c[F25519_SIZE]; |
| wolfSSL | 4:1b0d80432c79 | 500 | int ret = 0; |
| wolfSSL | 4:1b0d80432c79 | 501 | |
| wolfSSL | 4:1b0d80432c79 | 502 | /* unpack the key s */ |
| wolfSSL | 4:1b0d80432c79 | 503 | parity = s[31] >> 7; |
| wolfSSL | 4:1b0d80432c79 | 504 | fe_copy(y, s); |
| wolfSSL | 4:1b0d80432c79 | 505 | y[31] &= 127; |
| wolfSSL | 4:1b0d80432c79 | 506 | |
| wolfSSL | 4:1b0d80432c79 | 507 | fe_mul__distinct(c, y, y); |
| wolfSSL | 4:1b0d80432c79 | 508 | fe_mul__distinct(b, c, ed25519_d); |
| wolfSSL | 4:1b0d80432c79 | 509 | fe_add(a, b, f25519_one); |
| wolfSSL | 4:1b0d80432c79 | 510 | fe_inv__distinct(b, a); |
| wolfSSL | 4:1b0d80432c79 | 511 | fe_sub(a, c, f25519_one); |
| wolfSSL | 4:1b0d80432c79 | 512 | fe_mul__distinct(c, a, b); |
| wolfSSL | 4:1b0d80432c79 | 513 | fe_sqrt(a, c); |
| wolfSSL | 4:1b0d80432c79 | 514 | fe_neg(b, a); |
| wolfSSL | 4:1b0d80432c79 | 515 | fe_select(x, a, b, (a[0] ^ parity) & 1); |
| wolfSSL | 4:1b0d80432c79 | 516 | |
| wolfSSL | 4:1b0d80432c79 | 517 | /* test that x^2 is equal to c */ |
| wolfSSL | 4:1b0d80432c79 | 518 | fe_mul__distinct(a, x, x); |
| wolfSSL | 4:1b0d80432c79 | 519 | fe_normalize(a); |
| wolfSSL | 4:1b0d80432c79 | 520 | fe_normalize(c); |
| wolfSSL | 4:1b0d80432c79 | 521 | ret |= ConstantCompare(a, c, F25519_SIZE); |
| wolfSSL | 4:1b0d80432c79 | 522 | |
| wolfSSL | 4:1b0d80432c79 | 523 | /* project the key s onto p */ |
| wolfSSL | 4:1b0d80432c79 | 524 | fe_copy(p->X, x); |
| wolfSSL | 4:1b0d80432c79 | 525 | fe_copy(p->Y, y); |
| wolfSSL | 4:1b0d80432c79 | 526 | fe_load(p->Z, 1); |
| wolfSSL | 4:1b0d80432c79 | 527 | fe_mul__distinct(p->T, x, y); |
| wolfSSL | 4:1b0d80432c79 | 528 | |
| wolfSSL | 4:1b0d80432c79 | 529 | /* negate, the point becomes (-X,Y,Z,-T) */ |
| wolfSSL | 4:1b0d80432c79 | 530 | fe_neg(p->X,p->X); |
| wolfSSL | 4:1b0d80432c79 | 531 | fe_neg(p->T,p->T); |
| wolfSSL | 4:1b0d80432c79 | 532 | |
| wolfSSL | 4:1b0d80432c79 | 533 | return ret; |
| wolfSSL | 4:1b0d80432c79 | 534 | } |
| wolfSSL | 4:1b0d80432c79 | 535 | |
| wolfSSL | 4:1b0d80432c79 | 536 | |
| wolfSSL | 4:1b0d80432c79 | 537 | int ge_double_scalarmult_vartime(ge_p2* R, const unsigned char *h, |
| wolfSSL | 4:1b0d80432c79 | 538 | const ge_p3 *inA,const unsigned char *sig) |
| wolfSSL | 4:1b0d80432c79 | 539 | { |
| wolfSSL | 4:1b0d80432c79 | 540 | ge_p3 p, A; |
| wolfSSL | 4:1b0d80432c79 | 541 | int ret = 0; |
| wolfSSL | 4:1b0d80432c79 | 542 | |
| wolfSSL | 4:1b0d80432c79 | 543 | XMEMCPY(&A, inA, sizeof(ge_p3)); |
| wolfSSL | 4:1b0d80432c79 | 544 | |
| wolfSSL | 4:1b0d80432c79 | 545 | /* find SB */ |
| wolfSSL | 4:1b0d80432c79 | 546 | ed25519_smult(&p, &ed25519_base, sig); |
| wolfSSL | 4:1b0d80432c79 | 547 | |
| wolfSSL | 4:1b0d80432c79 | 548 | /* find H(R,A,M) * -A */ |
| wolfSSL | 4:1b0d80432c79 | 549 | ed25519_smult(&A, &A, h); |
| wolfSSL | 4:1b0d80432c79 | 550 | |
| wolfSSL | 4:1b0d80432c79 | 551 | /* SB + -H(R,A,M)A */ |
| wolfSSL | 4:1b0d80432c79 | 552 | ed25519_add(&A, &p, &A); |
| wolfSSL | 4:1b0d80432c79 | 553 | |
| wolfSSL | 4:1b0d80432c79 | 554 | fe_copy(R->X, A.X); |
| wolfSSL | 4:1b0d80432c79 | 555 | fe_copy(R->Y, A.Y); |
| wolfSSL | 4:1b0d80432c79 | 556 | fe_copy(R->Z, A.Z); |
| wolfSSL | 4:1b0d80432c79 | 557 | |
| wolfSSL | 4:1b0d80432c79 | 558 | return ret; |
| wolfSSL | 4:1b0d80432c79 | 559 | } |
| wolfSSL | 4:1b0d80432c79 | 560 | |
| wolfSSL | 4:1b0d80432c79 | 561 | #endif /* HAVE_ED25519 */ |
| wolfSSL | 4:1b0d80432c79 | 562 | #endif /* CURVED25519_SMALL */ |
| wolfSSL | 4:1b0d80432c79 | 563 | |
| wolfSSL | 4:1b0d80432c79 | 564 |