2 // PublicKey.cs - System.Security.Cryptography.PublicKey
5 // Sebastien Pouliot <sebastien@ximian.com>
6 // Tim Coleman (tim@timcoleman.com)
8 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)
9 // Copyright (C) Tim Coleman, 2004
10 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
12 // Permission is hereby granted, free of charge, to any person obtaining
13 // a copy of this software and associated documentation files (the
14 // "Software"), to deal in the Software without restriction, including
15 // without limitation the rights to use, copy, modify, merge, publish,
16 // distribute, sublicense, and/or sell copies of the Software, and to
17 // permit persons to whom the Software is furnished to do so, subject to
18 // the following conditions:
20 // The above copyright notice and this permission notice shall be
21 // included in all copies or substantial portions of the Software.
23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
36 using Mono.Security.Cryptography;
37 using MSX = Mono.Security.X509;
39 extern alias MonoSecurity;
40 using MonoSecurity::Mono.Security;
41 using MonoSecurity::Mono.Security.Cryptography;
42 using MSX = MonoSecurity::Mono.Security.X509;
45 namespace System.Security.Cryptography.X509Certificates {
47 public sealed class PublicKey {
49 private const string rsaOid = "1.2.840.113549.1.1.1";
50 private const string dsaOid = "1.2.840.10040.4.1";
52 private AsymmetricAlgorithm _key;
53 private AsnEncodedData _keyValue;
54 private AsnEncodedData _params;
57 static byte[] Empty = new byte [0];
59 public PublicKey (Oid oid, AsnEncodedData parameters, AsnEncodedData keyValue)
62 throw new ArgumentNullException ("oid");
63 if (parameters == null)
64 throw new ArgumentNullException ("parameters");
66 throw new ArgumentNullException ("keyValue");
69 _params = new AsnEncodedData (parameters);
70 _keyValue = new AsnEncodedData (keyValue);
73 internal PublicKey (MSX.X509Certificate certificate)
75 // note: _key MUSTonly contains the public part of the key
76 bool export_required = true;
78 if (certificate.KeyAlgorithm == rsaOid) {
79 // shortcut export/import in the case the private key isn't available
80 RSACryptoServiceProvider rcsp = (certificate.RSA as RSACryptoServiceProvider);
81 if ((rcsp != null) && rcsp.PublicOnly) {
82 _key = certificate.RSA;
83 export_required = false;
86 RSAManaged rsam = (certificate.RSA as RSAManaged);
87 if ((rsam != null) && rsam.PublicOnly) {
88 _key = certificate.RSA;
89 export_required = false;
93 if (export_required) {
94 RSAParameters rsap = certificate.RSA.ExportParameters (false);
96 (_key as RSA).ImportParameters (rsap);
99 // shortcut export/import in the case the private key isn't available
100 DSACryptoServiceProvider dcsp = (certificate.DSA as DSACryptoServiceProvider);
101 if ((dcsp != null) && dcsp.PublicOnly) {
102 _key = certificate.DSA;
103 export_required = false;
105 // note: DSAManaged isn't available in Mono.Security due to a bug in Fx 1.x
107 if (export_required) {
108 DSAParameters rsap = certificate.DSA.ExportParameters (false);
109 _key = DSA.Create ();
110 (_key as DSA).ImportParameters (rsap);
114 _oid = new Oid (certificate.KeyAlgorithm);
115 _keyValue = new AsnEncodedData (_oid, certificate.PublicKey);
116 _params = new AsnEncodedData (_oid, certificate.KeyAlgorithmParameters ?? Empty);
121 public AsnEncodedData EncodedKeyValue {
122 get { return _keyValue; }
125 public AsnEncodedData EncodedParameters {
126 get { return _params; }
129 public AsymmetricAlgorithm Key {
132 switch (_oid.Value) {
134 _key = DecodeRSA (_keyValue.RawData);
137 _key = DecodeDSA (_keyValue.RawData, _params.RawData);
140 string msg = Locale.GetText ("Cannot decode public key from unknown OID '{0}'.", _oid.Value);
141 throw new NotSupportedException (msg);
154 static private byte[] GetUnsignedBigInteger (byte[] integer)
156 if (integer [0] != 0x00)
159 // this first byte is added so we're sure it's an unsigned integer
160 // however we can't feed it into RSAParameters or DSAParameters
161 int length = integer.Length - 1;
162 byte[] uinteger = new byte [length];
163 Buffer.BlockCopy (integer, 1, uinteger, 0, length);
167 static internal DSA DecodeDSA (byte[] rawPublicKey, byte[] rawParameters)
169 DSAParameters dsaParams = new DSAParameters ();
171 // for DSA rawPublicKey contains 1 ASN.1 integer - Y
172 ASN1 pubkey = new ASN1 (rawPublicKey);
173 if (pubkey.Tag != 0x02)
174 throw new CryptographicException (Locale.GetText ("Missing DSA Y integer."));
175 dsaParams.Y = GetUnsignedBigInteger (pubkey.Value);
177 ASN1 param = new ASN1 (rawParameters);
178 if ((param == null) || (param.Tag != 0x30) || (param.Count < 3))
179 throw new CryptographicException (Locale.GetText ("Missing DSA parameters."));
180 if ((param [0].Tag != 0x02) || (param [1].Tag != 0x02) || (param [2].Tag != 0x02))
181 throw new CryptographicException (Locale.GetText ("Invalid DSA parameters."));
183 dsaParams.P = GetUnsignedBigInteger (param [0].Value);
184 dsaParams.Q = GetUnsignedBigInteger (param [1].Value);
185 dsaParams.G = GetUnsignedBigInteger (param [2].Value);
187 catch (Exception e) {
188 string msg = Locale.GetText ("Error decoding the ASN.1 structure.");
189 throw new CryptographicException (msg, e);
192 DSA dsa = (DSA) new DSACryptoServiceProvider (dsaParams.Y.Length << 3);
193 dsa.ImportParameters (dsaParams);
197 static internal RSA DecodeRSA (byte[] rawPublicKey)
199 RSAParameters rsaParams = new RSAParameters ();
201 // for RSA rawPublicKey contains 2 ASN.1 integers
202 // the modulus and the public exponent
203 ASN1 pubkey = new ASN1 (rawPublicKey);
204 if (pubkey.Count == 0)
205 throw new CryptographicException (Locale.GetText ("Missing RSA modulus and exponent."));
206 ASN1 modulus = pubkey [0];
207 if ((modulus == null) || (modulus.Tag != 0x02))
208 throw new CryptographicException (Locale.GetText ("Missing RSA modulus."));
209 ASN1 exponent = pubkey [1];
210 if (exponent.Tag != 0x02)
211 throw new CryptographicException (Locale.GetText ("Missing RSA public exponent."));
213 rsaParams.Modulus = GetUnsignedBigInteger (modulus.Value);
214 rsaParams.Exponent = exponent.Value;
216 catch (Exception e) {
217 string msg = Locale.GetText ("Error decoding the ASN.1 structure.");
218 throw new CryptographicException (msg, e);
221 int keySize = (rsaParams.Modulus.Length << 3);
222 RSA rsa = (RSA) new RSACryptoServiceProvider (keySize);
223 rsa.ImportParameters (rsaParams);