CryptoLib4Pascal/CryptoLib/src/Crypto/Generators/ClpDHGenerators.pas at fa75e69a46cf5d43b2eb68b4cbafd235903fe8a2 · Xor-el/CryptoLib4Pascal · GitHub

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
{ *********************************************************************************** }
{ *                              CryptoLib Library                                  * }
{ *                           Author - Ugochukwu Mmaduekwe                          * }
{ *                 Github Repository <https://github.com/Xor-el>                   * }
{ *                                                                                 * }
{ *  Distributed under the MIT software license, see the accompanying file LICENSE  * }
{ *          or visit http://www.opensource.org/licenses/mit-license.php.           * }
{ *                                                                                 * }
{ *                              Acknowledgements:                                  * }
{ *                                                                                 * }
{ *      Thanks to Sphere 10 Software (http://www.sphere10.com/) for sponsoring     * }
{ *                         the development of this library                         * }
{ * ******************************************************************************* * }

(* &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& *)

unit ClpDHGenerators;

{$I ..\..\Include\CryptoLib.inc}

interface

uses
  SysUtils,
  ClpIDHParameters,
  ClpIDHGenerators,
  ClpDHParameters,
  ClpAsymmetricCipherKeyPair,
  ClpIAsymmetricCipherKeyPair,
  ClpIKeyGenerationParameters,
  ClpDHKeyGeneratorHelper,
  ClpIAsymmetricCipherKeyPairGenerator,
  ClpISecureRandom,
  ClpDHParametersHelper,
  ClpBigInteger,
  ClpCryptoLibTypes;

resourcestring
  SParametersCannotBeNil = '"parameters" Cannot Be Nil';

type
  TDHKeyPairGenerator = class sealed(TInterfacedObject,
    IAsymmetricCipherKeyPairGenerator, IDHKeyPairGenerator)
  strict private
    FParam: IDHKeyGenerationParameters;
  public
    procedure Init(const AParameters: IKeyGenerationParameters);
    function GenerateKeyPair(): IAsymmetricCipherKeyPair;
  end;

  TDHBasicKeyPairGenerator = class sealed(TInterfacedObject,
    IAsymmetricCipherKeyPairGenerator, IDHBasicKeyPairGenerator)
  strict private
    FParam: IDHKeyGenerationParameters;
  public
    procedure Init(const AParameters: IKeyGenerationParameters);
    function GenerateKeyPair(): IAsymmetricCipherKeyPair;
  end;

  TDHParametersGenerator = class(TInterfacedObject, IDHParametersGenerator)
  strict private
    FCertainty, FSize: Int32;
    FRandom: ISecureRandom;
  public
    procedure Init(ASize, ACertainty: Int32; const ARandom: ISecureRandom);
    function GenerateParameters(): IDHParameters; virtual;
  end;

implementation

function TDHKeyPairGenerator.GenerateKeyPair: IAsymmetricCipherKeyPair;
var
  LDhp: IDHParameters;
  LX, LY: TBigInteger;
begin
  LDhp := FParam.Parameters;
  LX := TDHKeyGeneratorHelper.CalculatePrivate(LDhp, FParam.Random);
  LY := TDHKeyGeneratorHelper.CalculatePublic(LDhp, LX);
  Result := TAsymmetricCipherKeyPair.Create(TDHPublicKeyParameters.Create(LY,
    LDhp) as IDHPublicKeyParameters, TDHPrivateKeyParameters.Create(LX, LDhp)
    as IDHPrivateKeyParameters);
end;

procedure TDHKeyPairGenerator.Init(const AParameters: IKeyGenerationParameters);
begin
  if AParameters = nil then
    raise EArgumentNilCryptoLibException.CreateRes(@SParametersCannotBeNil);
  if not Supports(AParameters, IDHKeyGenerationParameters, FParam) then
    raise EArgumentNilCryptoLibException.CreateRes(@SParametersCannotBeNil);
end;

function TDHBasicKeyPairGenerator.GenerateKeyPair: IAsymmetricCipherKeyPair;
var
  LDhp: IDHParameters;
  LX, LY: TBigInteger;
begin
  LDhp := FParam.Parameters;
  LX := TDHKeyGeneratorHelper.CalculatePrivate(LDhp, FParam.Random);
  LY := TDHKeyGeneratorHelper.CalculatePublic(LDhp, LX);
  Result := TAsymmetricCipherKeyPair.Create(TDHPublicKeyParameters.Create(LY,
    LDhp) as IDHPublicKeyParameters, TDHPrivateKeyParameters.Create(LX, LDhp)
    as IDHPrivateKeyParameters);
end;

procedure TDHBasicKeyPairGenerator.Init(const AParameters: IKeyGenerationParameters);
begin
  if AParameters = nil then
    raise EArgumentNilCryptoLibException.CreateRes(@SParametersCannotBeNil);
  if not Supports(AParameters, IDHKeyGenerationParameters, FParam) then
    raise EArgumentNilCryptoLibException.CreateRes(@SParametersCannotBeNil);
end;

function TDHParametersGenerator.GenerateParameters: IDHParameters;
var
  LSafePrimes: TCryptoLibGenericArray<TBigInteger>;
  LP, LQ, LG: TBigInteger;
begin
  LSafePrimes := TDHParametersHelper.GenerateSafePrimes(FSize, FCertainty, FRandom, True);
  LP := LSafePrimes[0];
  LQ := LSafePrimes[1];
{$IFDEF DEBUG}
  Assert((LP.Int32ValueExact and 7) = 7);
{$ENDIF DEBUG}
  LG := TBigInteger.Two;
  Result := TDHParameters.Create(LP, LG, LQ, TBigInteger.Two, nil);
end;

procedure TDHParametersGenerator.Init(ASize, ACertainty: Int32;
  const ARandom: ISecureRandom);
begin
  FSize := ASize;
  FCertainty := ACertainty;
  FRandom := ARandom;
end;

end.