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
|
/*************************************************
* Blinder Source File *
* (C) 1999-2005 The Botan Project *
*************************************************/
#include <botan/blinding.h>
#include <botan/numthry.h>
namespace Botan {
/*************************************************
* Blinder Constructor *
*************************************************/
Blinder::Blinder()
{
reducer = 0;
}
/*************************************************
* Blinder Copy Constructor *
*************************************************/
Blinder::Blinder(const Blinder& blinder)
{
reducer = 0;
initialize(blinder.e, blinder.d, blinder.n);
}
/*************************************************
* Blinder Assignment Operator *
*************************************************/
Blinder& Blinder::operator=(const Blinder& blinder)
{
delete reducer;
reducer = 0;
if(blinder.reducer)
initialize(blinder.e, blinder.d, blinder.n);
return (*this);
}
/*************************************************
* Initialize a Blinder object *
*************************************************/
void Blinder::initialize(const BigInt& e1, const BigInt& d1, const BigInt& n1)
{
if(e1 < 1 || d1 < 1 || n1 < 1)
throw Invalid_Argument("Blinder::initialize: Arguments too small");
e = e1;
d = d1;
n = n1;
delete reducer;
reducer = get_reducer(n);
}
/*************************************************
* Blinder Destructor *
*************************************************/
Blinder::~Blinder()
{
delete reducer;
}
/*************************************************
* Blind a number *
*************************************************/
BigInt Blinder::blind(const BigInt& i) const
{
if(!reducer) return i;
e = reducer->square(e);
d = reducer->square(d);
return reducer->multiply(i, e);
}
/*************************************************
* Unblind a number *
*************************************************/
BigInt Blinder::unblind(const BigInt& i) const
{
if(!reducer) return i;
return reducer->multiply(i, d);
}
}
|
