//
// PublicKey.cs - System.Security.Cryptography.PublicKey
//
// Author:
// 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
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
#if SECURITY_DEP || MOONLIGHT
using Mono.Security;
using Mono.Security.Cryptography;
using MSXMono.Security.X509;
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;
public PublicKey (Oid oid, AsnEncodedData parameters, AsnEncodedData 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 (MSX.X509Certificate certificate)
{
// note: _key MUSTonly contains the public part of the key
bool export_required = true;
if (certificate.KeyAlgorithm == rsaOid) {
#if !MOONLIGHT
// shortcut export/import in the case the private key isn't available
RSACryptoServiceProvider rcsp = (certificate.RSA as RSACryptoServiceProvider);
if ((rcsp != null) && rcsp.PublicOnly) {
_key = certificate.RSA;
export_required = false;
} else
#endif
{
RSAManaged rsam = (certificate.RSA as RSAManaged);
if ((rsam != null) && rsam.PublicOnly) {
_key = certificate.RSA;
export_required = false;
}
}
if (export_required) {
RSAParameters rsap = certificate.RSA.ExportParameters (false);
_key = RSA.Create ();
(_key as RSA).ImportParameters (rsap);
}
} else {
#if !MOONLIGHT
// shortcut export/import in the case the private key isn't available
DSACryptoServiceProvider dcsp = (certificate.DSA as DSACryptoServiceProvider);
if ((dcsp != null) && dcsp.PublicOnly) {
_key = certificate.DSA;
export_required = false;
}
// note: DSAManaged isn't available in Mono.Security due to a bug in Fx 1.x
if (export_required) {
DSAParameters rsap = certificate.DSA.ExportParameters (false);
_key = DSA.Create ();
(_key as DSA).ImportParameters (rsap);
}
#endif
}
_oid = new Oid (certificate.KeyAlgorithm);
_keyValue = new AsnEncodedData (_oid, certificate.PublicKey);
_params = new AsnEncodedData (_oid, certificate.KeyAlgorithmParameters);
}
// properties
public AsnEncodedData EncodedKeyValue {
get { return _keyValue; }
}
public AsnEncodedData EncodedParameters {
get { return _params; }
}
public AsymmetricAlgorithm 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);
}
#if MOONLIGHT
DSA dsa = (DSA) new DSAManaged (dsaParams.Y.Length << 3);
#else
DSA dsa = (DSA) new DSACryptoServiceProvider (dsaParams.Y.Length << 3);
#endif
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);
#if MOONLIGHT
RSA rsa = (RSA) new RSAManaged (keySize);
#else
RSA rsa = (RSA) new RSACryptoServiceProvider (keySize);
#endif
rsa.ImportParameters (rsaParams);
return rsa;
}
}
}
#endif
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