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
|
//
// KeyUsageExtension.cs: Handles X.509 KeyUsage extensions.
//
// Author:
// Sebastien Pouliot <sebastien@ximian.com>
//
// (C) 2003 Motus Technologies Inc. (http://www.motus.com)
// (C) 2004 Novell (http://www.novell.com)
//
using System;
using System.Globalization;
using System.Text;
using Mono.Security;
using Mono.Security.X509;
namespace Mono.Security.X509.Extensions {
/*
* id-ce-keyUsage OBJECT IDENTIFIER ::= { id-ce 15 }
*
* KeyUsage ::= BIT STRING {
* digitalSignature (0),
* nonRepudiation (1),
* keyEncipherment (2),
* dataEncipherment (3),
* keyAgreement (4),
* keyCertSign (5),
* cRLSign (6),
* encipherOnly (7),
* decipherOnly (8)
* }
*/
// note: because nothing is simple in ASN.1 bits are reversed
[Flags]
#if INSIDE_CORLIB
internal
#else
public
#endif
enum KeyUsages {
digitalSignature = 0x80,
nonRepudiation = 0x40,
keyEncipherment = 0x20,
dataEncipherment = 0x10,
keyAgreement = 0x08,
keyCertSign = 0x04,
cRLSign = 0x02,
encipherOnly = 0x01,
decipherOnly = 0x800,
none = 0x0
}
#if INSIDE_CORLIB
internal
#else
public
#endif
class KeyUsageExtension : X509Extension {
private int kubits;
public KeyUsageExtension (ASN1 asn1) : base (asn1) {}
public KeyUsageExtension (X509Extension extension) : base (extension) {}
protected override void Decode ()
{
ASN1 bitString = new ASN1 (extnValue.Value);
if (bitString.Tag != 0x03)
throw new ArgumentException ("Invalid KeyUsage extension");
int i = 1; // byte zero has the number of unused bits (ASN1's BITSTRING)
while (i < bitString.Value.Length)
kubits = (kubits << 8) + bitString.Value [i++];
}
public override string Name {
get { return "Key Usage"; }
}
public bool Support (KeyUsages usage)
{
int x = Convert.ToInt32 (usage, CultureInfo.InvariantCulture);
return ((x & kubits) == x);
}
public override string ToString ()
{
const string separator = " , ";
StringBuilder sb = new StringBuilder ();
if (Support (KeyUsages.digitalSignature))
sb.Append ("Digital Signature");
if (Support (KeyUsages.nonRepudiation)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Non-Repudiation");
}
if (Support (KeyUsages.keyEncipherment)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Key Encipherment");
}
if (Support (KeyUsages.dataEncipherment)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Data Encipherment");
}
if (Support (KeyUsages.keyAgreement)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Key Agreement");
}
if (Support (KeyUsages.keyCertSign)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Certificate Signing");
}
if (Support (KeyUsages.cRLSign)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("CRL Signing");
}
if (Support (KeyUsages.encipherOnly)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Encipher Only "); // ???
}
if (Support (KeyUsages.decipherOnly)) {
if (sb.Length > 0)
sb.Append (separator);
sb.Append ("Decipher Only"); // ???
}
sb.Append ("(");
sb.Append (kubits.ToString ("X2", CultureInfo.InvariantCulture));
sb.Append (")");
sb.Append (Environment.NewLine);
return sb.ToString ();
}
}
}
|
