1 files changed, 114 insertions, 0 deletions
diff --git a/crypto/src/bcpg/RsaSecretBcpgKey.cs b/crypto/src/bcpg/RsaSecretBcpgKey.cs
new file mode 100644
index 000000000..5c04d9f85
--- /dev/null
+++ b/crypto/src/bcpg/RsaSecretBcpgKey.cs
@@ -0,0 +1,114 @@
+using System;
+
+using Org.BouncyCastle.Math;
+
+namespace Org.BouncyCastle.Bcpg
+{
+	/// <remarks>Base class for an RSA secret (or priate) key.</remarks>
+	public class RsaSecretBcpgKey
+		: BcpgObject, IBcpgKey
+	{
+		private readonly MPInteger d, p, q, u;
+		private readonly BigInteger expP, expQ, crt;
+
+		public RsaSecretBcpgKey(
+			BcpgInputStream bcpgIn)
+		{
+			this.d = new MPInteger(bcpgIn);
+			this.p = new MPInteger(bcpgIn);
+			this.q = new MPInteger(bcpgIn);
+			this.u = new MPInteger(bcpgIn);
+
+			this.expP = d.Value.Remainder(p.Value.Subtract(BigInteger.One));
+			this.expQ = d.Value.Remainder(q.Value.Subtract(BigInteger.One));
+			this.crt = q.Value.ModInverse(p.Value);
+		}
+
+		public RsaSecretBcpgKey(
+			BigInteger d,
+			BigInteger p,
+			BigInteger q)
+		{
+			// PGP requires (p < q)
+			int cmp = p.CompareTo(q);
+			if (cmp >= 0)
+			{
+				if (cmp == 0)
+					throw new ArgumentException("p and q cannot be equal");
+
+				BigInteger tmp = p;
+				p = q;
+				q = tmp;
+			}
+
+			this.d = new MPInteger(d);
+			this.p = new MPInteger(p);
+			this.q = new MPInteger(q);
+			this.u = new MPInteger(p.ModInverse(q));
+
+			this.expP = d.Remainder(p.Subtract(BigInteger.One));
+			this.expQ = d.Remainder(q.Subtract(BigInteger.One));
+			this.crt = q.ModInverse(p);
+		}
+
+		public BigInteger Modulus
+		{
+			get { return p.Value.Multiply(q.Value); }
+		}
+
+		public BigInteger PrivateExponent
+		{
+			get { return d.Value; }
+		}
+
+		public BigInteger PrimeP
+		{
+			get { return p.Value; }
+		}
+
+		public BigInteger PrimeQ
+		{
+			get { return q.Value; }
+		}
+
+		public BigInteger PrimeExponentP
+		{
+			get { return expP; }
+		}
+
+		public BigInteger PrimeExponentQ
+		{
+			get { return expQ; }
+		}
+
+		public BigInteger CrtCoefficient
+		{
+			get { return crt; }
+		}
+
+		/// <summary>The format, as a string, always "PGP".</summary>
+		public string Format
+		{
+			get { return "PGP"; }
+		}
+
+		/// <summary>Return the standard PGP encoding of the key.</summary>
+		public override byte[] GetEncoded()
+		{
+			try
+			{
+				return base.GetEncoded();
+			}
+			catch (Exception)
+			{
+				return null;
+			}
+		}
+
+		public override void Encode(
+			BcpgOutputStream bcpgOut)
+		{
+			bcpgOut.WriteObjects(d, p, q, u);
+		}
+	}
+}