2005-11-22 Sebastien Pouliot <sebastien@ximian.com>

	* PublicKey.cs: Completed implementation for both RSA and DSA public
	keys.


svn path=/trunk/mcs/; revision=53358

2 files changed, 117 insertions, 14 deletions

diff --git a/mcs/class/System/System.Security.Cryptography.X509Certificates/ChangeLog b/mcs/class/System/System.Security.Cryptography.X509Certificates/ChangeLog
index 3d24210a348..e6bdd73a3a1 100644
--- a/mcs/class/System/System.Security.Cryptography.X509Certificates/ChangeLog
+++ b/mcs/class/System/System.Security.Cryptography.X509Certificates/ChangeLog
@@ -1,3 +1,8 @@
+2005-11-22  Sebastien Pouliot  <sebastien@ximian.com>
+
+	* PublicKey.cs: Completed implementation for both RSA and DSA public
+	keys.
+
 2005-11-08  Sebastien Pouliot  <sebastien@ximian.com>
 
 	* OpenFlags.cs: Removed extra [Serializable] (not in 2.0).
diff --git a/mcs/class/System/System.Security.Cryptography.X509Certificates/PublicKey.cs b/mcs/class/System/System.Security.Cryptography.X509Certificates/PublicKey.cs
index 1f4f840f5f4..0ad64d445e8 100644
--- a/mcs/class/System/System.Security.Cryptography.X509Certificates/PublicKey.cs
+++ b/mcs/class/System/System.Security.Cryptography.X509Certificates/PublicKey.cs
@@ -2,13 +2,12 @@
 // PublicKey.cs - System.Security.Cryptography.PublicKey
 //
 // Author:
-//	Sebastien Pouliot (spouliot@motus.com)
+//	Sebastien Pouliot  <sebastien@ximian.com>
 //	Tim Coleman (tim@timcoleman.com)
 //
 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)
 // Copyright (C) Tim Coleman, 2004
-//
-
+// Copyright (C) 2005 Novell, Inc (http://www.novell.com)
 //
 // Permission is hereby granted, free of charge, to any person obtaining
 // a copy of this software and associated documentation files (the
@@ -32,31 +31,40 @@
 
 #if NET_2_0 && SECURITY_DEP
 
-namespace System.Security.Cryptography.X509Certificates {
+using Mono.Security;
+using MSX = Mono.Security.X509;
 
-	// Note: Match the definition of framework version 1.2.3400.0 on http://longhorn.msdn.microsoft.com
+namespace System.Security.Cryptography.X509Certificates {
 
 	public sealed class PublicKey {
 
+		private const string rsaOid = "1.2.840.113549.1.1.1";
+		private const string dsaOid = "1.2.840.10040.4.1";
+
 		private AsymmetricAlgorithm _key;
 		private AsnEncodedData _keyValue;
 		private AsnEncodedData _params;
 		private Oid _oid;
 
-		[MonoTODO]
 		public PublicKey (Oid oid, AsnEncodedData parameters, AsnEncodedData keyValue)
 		{
-			_oid = oid;
-			_params = parameters;
-			_keyValue = keyValue;
+			if (oid == null)
+				throw new ArgumentNullException ("oid");
+			if (parameters == null)
+				throw new ArgumentNullException ("parameters");
+			if (keyValue == null)
+				throw new ArgumentNullException ("keyValue");
+
+			_oid = new Oid (oid);
+			_params = new AsnEncodedData (parameters);
+			_keyValue = new AsnEncodedData (keyValue);
 		}
 
-		internal PublicKey (Mono.Security.X509.X509Certificate certificate)
+		internal PublicKey (MSX.X509Certificate certificate)
 		{
-			if (certificate.KeyAlgorithm == "1.2.840.113549.1.1.1") {
+			if (certificate.KeyAlgorithm == rsaOid) {
 				_key = certificate.RSA;
-			}
-			else {
+			} else {
 				_key = certificate.DSA;
 			}
 
@@ -76,12 +84,102 @@ namespace System.Security.Cryptography.X509Certificates {
 		}
 
 		public AsymmetricAlgorithm Key {
-			get { return _key; }
+			get {
+				if (_key == null) {
+					switch (_oid.Value) {
+					case rsaOid:
+						_key = DecodeRSA (_keyValue.RawData);
+						break;
+					case dsaOid:
+						_key = DecodeDSA (_keyValue.RawData, _params.RawData);
+						break;
+					default:
+						string msg = Locale.GetText ("Cannot decode public key from unknown OID '{0}'.", _oid.Value);
+						throw new NotSupportedException (msg);
+					}
+				}
+				return _key;
+			}
 		}
 
 		public Oid Oid {
 			get { return _oid; }
 		}
+
+		// private stuff
+
+		static private byte[] GetUnsignedBigInteger (byte[] integer) 
+		{
+			if (integer [0] != 0x00)
+				return integer;
+
+			// this first byte is added so we're sure it's an unsigned integer
+			// however we can't feed it into RSAParameters or DSAParameters
+			int length = integer.Length - 1;
+			byte[] uinteger = new byte [length];
+			Buffer.BlockCopy (integer, 1, uinteger, 0, length);
+			return uinteger;
+		}
+
+		static internal DSA DecodeDSA (byte[] rawPublicKey, byte[] rawParameters)
+		{
+			DSAParameters dsaParams = new DSAParameters ();
+			try {
+				// for DSA rawPublicKey contains 1 ASN.1 integer - Y
+				ASN1 pubkey = new ASN1 (rawPublicKey);
+				if (pubkey.Tag != 0x02)
+					throw new CryptographicException (Locale.GetText ("Missing DSA Y integer."));
+				dsaParams.Y = GetUnsignedBigInteger (pubkey.Value);
+
+				ASN1 param = new ASN1 (rawParameters);
+				if ((param == null) || (param.Tag != 0x30) || (param.Count < 3))
+					throw new CryptographicException (Locale.GetText ("Missing DSA parameters."));
+				if ((param [0].Tag != 0x02) || (param [1].Tag != 0x02) || (param [2].Tag != 0x02))
+					throw new CryptographicException (Locale.GetText ("Invalid DSA parameters."));
+
+				dsaParams.P = GetUnsignedBigInteger (param [0].Value);
+				dsaParams.Q = GetUnsignedBigInteger (param [1].Value);
+				dsaParams.G = GetUnsignedBigInteger (param [2].Value);
+			}
+			catch (Exception e) {
+				string msg = Locale.GetText ("Error decoding the ASN.1 structure.");
+				throw new CryptographicException (msg, e);
+			}
+
+			DSA dsa = (DSA) new DSACryptoServiceProvider (dsaParams.Y.Length << 3);
+			dsa.ImportParameters (dsaParams);
+			return dsa;
+		}
+
+		static internal RSA DecodeRSA (byte[] rawPublicKey)
+		{
+			RSAParameters rsaParams = new RSAParameters ();
+			try {
+				// for RSA rawPublicKey contains 2 ASN.1 integers
+				// the modulus and the public exponent
+				ASN1 pubkey = new ASN1 (rawPublicKey);
+				if (pubkey.Count == 0)
+					throw new CryptographicException (Locale.GetText ("Missing RSA modulus and exponent."));
+				ASN1 modulus = pubkey [0];
+				if ((modulus == null) || (modulus.Tag != 0x02))
+					throw new CryptographicException (Locale.GetText ("Missing RSA modulus."));
+				ASN1 exponent = pubkey [1];
+				if (exponent.Tag != 0x02)
+					throw new CryptographicException (Locale.GetText ("Missing RSA public exponent."));
+
+				rsaParams.Modulus = GetUnsignedBigInteger (modulus.Value);
+				rsaParams.Exponent = exponent.Value;
+			}
+			catch (Exception e) {
+				string msg = Locale.GetText ("Error decoding the ASN.1 structure.");
+				throw new CryptographicException (msg, e);
+			}
+
+			int keySize = (rsaParams.Modulus.Length << 3);
+			RSA rsa = (RSA) new RSACryptoServiceProvider (keySize);
+			rsa.ImportParameters (rsaParams);
+			return rsa;
+		}
 	}
 }