aboutsummaryrefslogtreecommitdiff
path: root/src/ringct/rctOps.h
blob: 3eb51be281aef5eefa523c8ccad55fe4df117dce (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
//#define DBG
// Copyright (c) 2016, Monero Research Labs
//
// Author: Shen Noether <shen.noether@gmx.com>
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
//    conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
//    of conditions and the following disclaimer in the documentation and/or other
//    materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
//    used to endorse or promote products derived from this software without specific
//    prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#pragma once

#ifndef RCTOPS_H
#define RCTOPS_H

#include <cstddef>
#include <mutex>
#include <vector>
#include <tuple>

#include "crypto/generic-ops.h"

extern "C" {
#include "crypto/random.h"
#include "crypto/keccak.h"
#include "rctCryptoOps.h"
}
#include "crypto/crypto.h"

#include "rctTypes.h"

//Define this flag when debugging to get additional info on the console
#ifdef DBG
#define DP(x) dp(x)
#else
#define DP(x)
#endif

using namespace std;
using namespace crypto;

namespace rct {

    //Various key initialization functions

    //Creates a zero scalar
    key zero();
    void zero(key &z);
    //Creates a zero elliptic curve point
    key identity();
    void identity(key &Id);
    //copies a scalar or point
    void copy(key &AA, const key &A);
    key copy(const key & AA);
    //initializes a key matrix;
    //first parameter is rows, 
    //second is columns
    keyM keyMInit(int, int);

    //Various key generation functions        

    //generates a random scalar which can be used as a secret key or mask
    key skGen();
    void skGen(key &);
    
    //generates a vector of secret keys of size "int"
    keyV skvGen(int );
    
    //generates a random curve point (for testing)
    key pkGen();
    //generates a random secret and corresponding public key
    void skpkGen(key &sk, key &pk);
    tuple<key, key> skpkGen();
    //generates a <secret , public> / Pedersen commitment to the amount
    tuple<ctkey, ctkey> ctskpkGen(xmr_amount amount);
    //this one is mainly for testing, can take arbitrary amounts..
    tuple<ctkey, ctkey> ctskpkGen(key bH);
    // make a pedersen commitment with given key
    key commit(xmr_amount amount, key mask);
    // make a pedersen commitment with zero key
    key zeroCommit(xmr_amount amount);
    //generates a random uint long long
    xmr_amount randXmrAmount(xmr_amount upperlimit);

    //Scalar multiplications of curve points        

    //does a * G where a is a scalar and G is the curve basepoint
    void scalarmultBase(key & aG, const key &a);
    key scalarmultBase(const key & a);
    //does a * P where a is a scalar and P is an arbitrary point
    void scalarmultKey(key &aP, const key &P, const key &a);
    key scalarmultKey(const key &P, const key &a);
    //Computes aH where H= toPoint(cn_fast_hash(G)), G the basepoint
    key scalarmultH(const key & a);

    //Curve addition / subtractions

    //for curve points: AB = A + B
    void addKeys(key &AB, const key &A, const key &B);
    //aGB = aG + B where a is a scalar, G is the basepoint, and B is a point
    void addKeys1(key &aGB, const key &a, const key & B);
    //aGbB = aG + bB where a, b are scalars, G is the basepoint and B is a point
    void addKeys2(key &aGbB, const key &a, const key &b, const key &B);
    //Does some precomputation to make addKeys3 more efficient
    // input B a curve point and output a ge_dsmp which has precomputation applied
    void precomp(ge_dsmp rv, const key &B);
    //aAbB = a*A + b*B where a, b are scalars, A, B are curve points
    //B must be input after applying "precomp"
    void addKeys3(key &aAbB, const key &a, const key &A, const key &b, const ge_dsmp B);
    //AB = A - B where A, B are curve points
    void subKeys(key &AB, const key &A, const  key &B);
    //checks if A, B are equal as curve points
    bool equalKeys(const key & A, const key & B);

    //Hashing - cn_fast_hash
    //be careful these are also in crypto namespace
    //cn_fast_hash for arbitrary l multiples of 32 bytes 
    void cn_fast_hash(key &hash, const void * data, const size_t l);
    void hash_to_scalar(key &hash, const void * data, const size_t l);
    //cn_fast_hash for a 32 byte key
    void cn_fast_hash(key &hash, const key &in);
    void hash_to_scalar(key &hash, const key &in);
    //cn_fast_hash for a 32 byte key
    key cn_fast_hash(const key &in);
    key hash_to_scalar(const key &in);
    //for mg sigs
    key cn_fast_hash128(const void * in);
    key hash_to_scalar128(const void * in);
    key cn_fast_hash(ctkeyV PC);
    key hash_to_scalar(ctkeyV PC);

    //returns hashToPoint as described in https://github.com/ShenNoether/ge_fromfe_writeup 
    key hashToPointSimple(const key &in);
    key hashToPoint(const key &in);
    void hashToPoint(key &out, const key &in);

    //sums a vector of curve points (for scalars use sc_add)
    void sumKeys(key & Csum, const key &Cis);

    //Elliptic Curve Diffie Helman: encodes and decodes the amount b and mask a
    // where C= aG + bH
    void ecdhEncode(ecdhTuple & unmasked, const key & receiverPk);
    void ecdhDecode(ecdhTuple & masked, const key & receiverSk);
}
#endif  /* RCTOPS_H */