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.
32 #if NET_2_0 && SECURITY_DEP
35 using Mono.Security.Cryptography;
36 using MSX = Mono.Security.X509;
38 namespace System.Security.Cryptography.X509Certificates {
40 public sealed class PublicKey {
42 private const string rsaOid = "1.2.840.113549.1.1.1";
43 private const string dsaOid = "1.2.840.10040.4.1";
45 private AsymmetricAlgorithm _key;
46 private AsnEncodedData _keyValue;
47 private AsnEncodedData _params;
50 public PublicKey (Oid oid, AsnEncodedData parameters, AsnEncodedData keyValue)
53 throw new ArgumentNullException ("oid");
54 if (parameters == null)
55 throw new ArgumentNullException ("parameters");
57 throw new ArgumentNullException ("keyValue");
60 _params = new AsnEncodedData (parameters);
61 _keyValue = new AsnEncodedData (keyValue);
64 internal PublicKey (MSX.X509Certificate certificate)
66 // note: _key MUSTonly contains the public part of the key
67 bool export_required = true;
69 if (certificate.KeyAlgorithm == rsaOid) {
70 // shortcut export/import in the case the private key isn't available
71 RSACryptoServiceProvider rcsp = (certificate.RSA as RSACryptoServiceProvider);
72 if ((rcsp != null) && rcsp.PublicOnly) {
73 _key = certificate.RSA;
74 export_required = false;
76 RSAManaged rsam = (certificate.RSA as RSAManaged);
77 if ((rsam != null) && rsam.PublicOnly) {
78 _key = certificate.RSA;
79 export_required = false;
83 if (export_required) {
84 RSAParameters rsap = certificate.RSA.ExportParameters (false);
86 (_key as RSA).ImportParameters (rsap);
89 // shortcut export/import in the case the private key isn't available
90 DSACryptoServiceProvider dcsp = (certificate.DSA as DSACryptoServiceProvider);
91 if ((dcsp != null) && dcsp.PublicOnly) {
92 _key = certificate.DSA;
93 export_required = false;
95 // note: DSAManaged isn't availablt in Mono.Security due to a bug in Fx 1.x
97 if (export_required) {
98 DSAParameters rsap = certificate.DSA.ExportParameters (false);
100 (_key as DSA).ImportParameters (rsap);
104 _oid = new Oid (certificate.KeyAlgorithm);
105 _keyValue = new AsnEncodedData (_oid, certificate.PublicKey);
106 _params = new AsnEncodedData (_oid, certificate.KeyAlgorithmParameters);
111 public AsnEncodedData EncodedKeyValue {
112 get { return _keyValue; }
115 public AsnEncodedData EncodedParameters {
116 get { return _params; }
119 public AsymmetricAlgorithm Key {
122 switch (_oid.Value) {
124 _key = DecodeRSA (_keyValue.RawData);
127 _key = DecodeDSA (_keyValue.RawData, _params.RawData);
130 string msg = Locale.GetText ("Cannot decode public key from unknown OID '{0}'.", _oid.Value);
131 throw new NotSupportedException (msg);
144 static private byte[] GetUnsignedBigInteger (byte[] integer)
146 if (integer [0] != 0x00)
149 // this first byte is added so we're sure it's an unsigned integer
150 // however we can't feed it into RSAParameters or DSAParameters
151 int length = integer.Length - 1;
152 byte[] uinteger = new byte [length];
153 Buffer.BlockCopy (integer, 1, uinteger, 0, length);
157 static internal DSA DecodeDSA (byte[] rawPublicKey, byte[] rawParameters)
159 DSAParameters dsaParams = new DSAParameters ();
161 // for DSA rawPublicKey contains 1 ASN.1 integer - Y
162 ASN1 pubkey = new ASN1 (rawPublicKey);
163 if (pubkey.Tag != 0x02)
164 throw new CryptographicException (Locale.GetText ("Missing DSA Y integer."));
165 dsaParams.Y = GetUnsignedBigInteger (pubkey.Value);
167 ASN1 param = new ASN1 (rawParameters);
168 if ((param == null) || (param.Tag != 0x30) || (param.Count < 3))
169 throw new CryptographicException (Locale.GetText ("Missing DSA parameters."));
170 if ((param [0].Tag != 0x02) || (param [1].Tag != 0x02) || (param [2].Tag != 0x02))
171 throw new CryptographicException (Locale.GetText ("Invalid DSA parameters."));
173 dsaParams.P = GetUnsignedBigInteger (param [0].Value);
174 dsaParams.Q = GetUnsignedBigInteger (param [1].Value);
175 dsaParams.G = GetUnsignedBigInteger (param [2].Value);
177 catch (Exception e) {
178 string msg = Locale.GetText ("Error decoding the ASN.1 structure.");
179 throw new CryptographicException (msg, e);
182 DSA dsa = (DSA) new DSACryptoServiceProvider (dsaParams.Y.Length << 3);
183 dsa.ImportParameters (dsaParams);
187 static internal RSA DecodeRSA (byte[] rawPublicKey)
189 RSAParameters rsaParams = new RSAParameters ();
191 // for RSA rawPublicKey contains 2 ASN.1 integers
192 // the modulus and the public exponent
193 ASN1 pubkey = new ASN1 (rawPublicKey);
194 if (pubkey.Count == 0)
195 throw new CryptographicException (Locale.GetText ("Missing RSA modulus and exponent."));
196 ASN1 modulus = pubkey [0];
197 if ((modulus == null) || (modulus.Tag != 0x02))
198 throw new CryptographicException (Locale.GetText ("Missing RSA modulus."));
199 ASN1 exponent = pubkey [1];
200 if (exponent.Tag != 0x02)
201 throw new CryptographicException (Locale.GetText ("Missing RSA public exponent."));
203 rsaParams.Modulus = GetUnsignedBigInteger (modulus.Value);
204 rsaParams.Exponent = exponent.Value;
206 catch (Exception e) {
207 string msg = Locale.GetText ("Error decoding the ASN.1 structure.");
208 throw new CryptographicException (msg, e);
211 int keySize = (rsaParams.Modulus.Length << 3);
212 RSA rsa = (RSA) new RSACryptoServiceProvider (keySize);
213 rsa.ImportParameters (rsaParams);