2 // System.Security.Cryptography.X509Certificates.X509KeyUsageExtension
5 // Tim Coleman (tim@timcoleman.com)
6 // Sebastien Pouliot <sebastien@ximian.com>
8 // Copyright (C) Tim Coleman, 2004
9 // Copyright (C) 2004-2005 Novell Inc. (http://www.novell.com)
11 // Permission is hereby granted, free of charge, to any person obtaining
12 // a copy of this software and associated documentation files (the
13 // "Software"), to deal in the Software without restriction, including
14 // without limitation the rights to use, copy, modify, merge, publish,
15 // distribute, sublicense, and/or sell copies of the Software, and to
16 // permit persons to whom the Software is furnished to do so, subject to
17 // the following conditions:
19 // The above copyright notice and this permission notice shall be
20 // included in all copies or substantial portions of the Software.
22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
36 extern alias MonoSecurity;
37 using MonoSecurity::Mono.Security;
42 namespace System.Security.Cryptography.X509Certificates {
44 public sealed class X509KeyUsageExtension : X509Extension {
46 internal const string oid = "2.5.29.15";
47 internal const string friendlyName = "Key Usage";
49 internal const X509KeyUsageFlags all = X509KeyUsageFlags.EncipherOnly | X509KeyUsageFlags.CrlSign |
50 X509KeyUsageFlags.KeyCertSign | X509KeyUsageFlags.KeyAgreement | X509KeyUsageFlags.DataEncipherment |
51 X509KeyUsageFlags.KeyEncipherment | X509KeyUsageFlags.NonRepudiation |
52 X509KeyUsageFlags.DigitalSignature | X509KeyUsageFlags.DecipherOnly;
54 private X509KeyUsageFlags _keyUsages;
55 private AsnDecodeStatus _status;
59 public X509KeyUsageExtension ()
61 _oid = new Oid (oid, friendlyName);
64 public X509KeyUsageExtension (AsnEncodedData encodedKeyUsage, bool critical)
66 // ignore the Oid provided by encodedKeyUsage (our rules!)
67 _oid = new Oid (oid, friendlyName);
68 _raw = encodedKeyUsage.RawData;
69 base.Critical = critical;
70 _status = Decode (this.RawData);
73 public X509KeyUsageExtension (X509KeyUsageFlags keyUsages, bool critical)
75 _oid = new Oid (oid, friendlyName);
76 base.Critical = critical;
77 _keyUsages = GetValidFlags (keyUsages);
83 public X509KeyUsageFlags KeyUsages {
86 case AsnDecodeStatus.Ok:
87 case AsnDecodeStatus.InformationNotAvailable:
90 throw new CryptographicException ("Badly encoded extension.");
97 public override void CopyFrom (AsnEncodedData encodedData)
99 if (encodedData == null)
100 throw new ArgumentNullException ("encodedData");
102 X509Extension ex = (encodedData as X509Extension);
104 throw new ArgumentException (Locale.GetText ("Wrong type."), "encodedData");
107 _oid = new Oid (oid, friendlyName);
109 _oid = new Oid (ex._oid);
111 RawData = ex.RawData;
112 base.Critical = ex.Critical;
113 // and we deal with the rest later
114 _status = Decode (this.RawData);
119 internal X509KeyUsageFlags GetValidFlags (X509KeyUsageFlags flags)
121 if ((flags & all) != flags)
122 return (X509KeyUsageFlags) 0;
126 internal AsnDecodeStatus Decode (byte[] extension)
128 if ((extension == null) || (extension.Length == 0))
129 return AsnDecodeStatus.BadAsn;
130 if (extension [0] != 0x03)
131 return AsnDecodeStatus.BadTag;
132 if (extension.Length < 3)
133 return AsnDecodeStatus.BadLength;
134 if (extension.Length < 4)
135 return AsnDecodeStatus.InformationNotAvailable;
138 ASN1 ex = new ASN1 (extension);
140 int i = 1; // byte zero has the number of unused bits (ASN1's BITSTRING)
141 while (i < ex.Value.Length)
142 kubits = (kubits << 8) + ex.Value [i++];
144 _keyUsages = GetValidFlags ((X509KeyUsageFlags)kubits);
147 return AsnDecodeStatus.BadAsn;
150 return AsnDecodeStatus.Ok;
153 internal byte[] Encode ()
156 int kubits = (int)_keyUsages;
160 ex = new ASN1 (0x03, new byte[] { empty });
162 // count empty bits (applicable to first byte only)
163 int ku = ((kubits < Byte.MaxValue) ? kubits : (kubits >> 8));
164 while (((ku & 0x01) == 0x00) && (empty < 8)) {
169 if (kubits <= Byte.MaxValue) {
170 ex = new ASN1 (0x03, new byte[] { empty, (byte)kubits });
172 ex = new ASN1 (0x03, new byte[] { empty, (byte)kubits, (byte)(kubits >> 8) });
176 return ex.GetBytes ();
179 internal override string ToString (bool multiLine)
182 case AsnDecodeStatus.BadAsn:
184 case AsnDecodeStatus.BadTag:
185 case AsnDecodeStatus.BadLength:
186 return FormatUnkownData (_raw);
187 case AsnDecodeStatus.InformationNotAvailable:
188 return "Information Not Available";
191 if (_oid.Value != oid)
192 return String.Format ("Unknown Key Usage ({0})", _oid.Value);
194 return "Information Not Available";
196 StringBuilder sb = new StringBuilder ();
198 if ((_keyUsages & X509KeyUsageFlags.DigitalSignature) != 0) {
199 sb.Append ("Digital Signature");
201 if ((_keyUsages & X509KeyUsageFlags.NonRepudiation) != 0) {
204 sb.Append ("Non-Repudiation");
206 if ((_keyUsages & X509KeyUsageFlags.KeyEncipherment) != 0) {
209 sb.Append ("Key Encipherment");
211 if ((_keyUsages & X509KeyUsageFlags.DataEncipherment) != 0) {
214 sb.Append ("Data Encipherment");
216 if ((_keyUsages & X509KeyUsageFlags.KeyAgreement) != 0) {
219 sb.Append ("Key Agreement");
221 if ((_keyUsages & X509KeyUsageFlags.KeyCertSign) != 0) {
224 sb.Append ("Certificate Signing");
226 if ((_keyUsages & X509KeyUsageFlags.CrlSign) != 0) {
229 sb.Append ("Off-line CRL Signing, CRL Signing");
231 if ((_keyUsages & X509KeyUsageFlags.EncipherOnly) != 0) {
234 sb.Append ("Encipher Only");
236 if ((_keyUsages & X509KeyUsageFlags.DecipherOnly) != 0) {
239 sb.Append ("Decipher Only");
242 int ku = (int)_keyUsages;
244 sb.Append (((byte)ku).ToString ("x2"));
245 if (ku > Byte.MaxValue) {
247 sb.Append (((byte)(ku >> 8)).ToString ("x2"));
252 sb.Append (Environment.NewLine);
254 return sb.ToString ();