Alexandre Lision | 7fd5d3d | 2013-12-04 13:06:40 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 Werner Dittmann |
| 3 | * All rights reserved. For licensing and other legal details, see the file legal.c. |
| 4 | * |
| 5 | * @author Werner Dittmann <Werner.Dittmann@t-online.de> |
| 6 | * |
| 7 | */ |
| 8 | |
| 9 | #include <ec/ec.h> |
| 10 | #include <ec/ecdh.h> |
| 11 | |
| 12 | int ecdhGeneratePublic(const EcCurve *curve, EcPoint *Q, const BigNum *d) |
| 13 | { |
| 14 | EcPoint G; |
| 15 | |
| 16 | INIT_EC_POINT(&G); |
| 17 | SET_EC_BASE_POINT(curve, &G); |
| 18 | |
| 19 | ecMulPointScalar(curve, Q, &G, d); |
| 20 | ecGetAffine(curve, Q, Q); |
| 21 | |
| 22 | FREE_EC_POINT(&G); |
| 23 | |
| 24 | return ecCheckPubKey(curve, Q); |
| 25 | } |
| 26 | |
| 27 | int ecdhComputeAgreement(const EcCurve *curve, BigNum *agreement, const EcPoint *Q, const BigNum *d) |
| 28 | { |
| 29 | EcPoint t0; |
| 30 | |
| 31 | INIT_EC_POINT(&t0); |
| 32 | |
| 33 | ecMulPointScalar(curve, &t0, Q, d); |
| 34 | ecGetAffine(curve, &t0, &t0); |
| 35 | /* TODO: check for infinity here */ |
| 36 | |
| 37 | bnCopy(agreement, t0.x); |
| 38 | |
| 39 | FREE_EC_POINT(&t0); |
| 40 | |
| 41 | return 0; |
| 42 | } |