Initial Commit

iTechSharp/srcbc/x509/X509CrlParser.cs

@@ -0,0 +1,194 @@
+using System;
+using System.Collections;
+using System.IO;
+using System.Text;
+
+using Org.BouncyCastle.Asn1;
+using Org.BouncyCastle.Asn1.Pkcs;
+using Org.BouncyCastle.Asn1.X509;
+using Org.BouncyCastle.Security.Certificates;
+using Org.BouncyCastle.Utilities.Encoders;
+using Org.BouncyCastle.Utilities.IO;
+
+namespace Org.BouncyCastle.X509
+{
+	public class X509CrlParser
+	{
+		private static readonly PemParser PemCrlParser = new PemParser("CRL");
+
+		private readonly bool lazyAsn1;
+
+		private Asn1Set	sCrlData;
+		private int		sCrlDataObjectCount;
+		private Stream	currentCrlStream;
+
+		public X509CrlParser()
+			: this(false)
+		{
+		}
+
+		public X509CrlParser(
+			bool lazyAsn1)
+		{
+			this.lazyAsn1 = lazyAsn1;
+		}
+
+		private X509Crl ReadPemCrl(
+			Stream inStream)
+		{
+			Asn1Sequence seq = PemCrlParser.ReadPemObject(inStream);
+
+			return seq == null
+				?	null
+				:	CreateX509Crl(CertificateList.GetInstance(seq));
+		}
+
+		private X509Crl ReadDerCrl(
+			Asn1InputStream dIn)
+		{
+			Asn1Sequence seq = (Asn1Sequence)dIn.ReadObject();
+
+			if (seq.Count > 1 && seq[0] is DerObjectIdentifier)
+			{
+				if (seq[0].Equals(PkcsObjectIdentifiers.SignedData))
+				{
+					sCrlData = SignedData.GetInstance(
+						Asn1Sequence.GetInstance((Asn1TaggedObject) seq[1], true)).Crls;
+
+					return GetCrl();
+				}
+			}
+
+			return CreateX509Crl(CertificateList.GetInstance(seq));
+		}
+
+		private X509Crl GetCrl()
+		{
+			if (sCrlData == null || sCrlDataObjectCount >= sCrlData.Count)
+			{
+				return null;
+			}
+
+			return CreateX509Crl(
+				CertificateList.GetInstance(
+					sCrlData[sCrlDataObjectCount++]));
+		}
+
+		protected virtual X509Crl CreateX509Crl(
+			CertificateList c)
+		{
+			return new X509Crl(c);
+		}
+
+		/// <summary>
+		/// Create loading data from byte array.
+		/// </summary>
+		/// <param name="input"></param>
+		public X509Crl ReadCrl(
+			byte[] input)
+		{
+			return ReadCrl(new MemoryStream(input, false));
+		}
+
+		/// <summary>
+		/// Create loading data from byte array.
+		/// </summary>
+		/// <param name="input"></param>
+		public ICollection ReadCrls(
+			byte[] input)
+		{
+			return ReadCrls(new MemoryStream(input, false));
+		}
+
+		/**
+		 * Generates a certificate revocation list (CRL) object and initializes
+		 * it with the data read from the input stream inStream.
+		 */
+		public X509Crl ReadCrl(
+			Stream inStream)
+		{
+			if (inStream == null)
+				throw new ArgumentNullException("inStream");
+			if (!inStream.CanRead)
+				throw new ArgumentException("inStream must be read-able", "inStream");
+
+			if (currentCrlStream == null)
+			{
+				currentCrlStream = inStream;
+				sCrlData = null;
+				sCrlDataObjectCount = 0;
+			}
+			else if (currentCrlStream != inStream) // reset if input stream has changed
+			{
+				currentCrlStream = inStream;
+				sCrlData = null;
+				sCrlDataObjectCount = 0;
+			}
+
+			try
+			{
+				if (sCrlData != null)
+				{
+					if (sCrlDataObjectCount != sCrlData.Count)
+					{
+						return GetCrl();
+					}
+
+					sCrlData = null;
+					sCrlDataObjectCount = 0;
+					return null;
+				}
+
+				PushbackStream pis = new PushbackStream(inStream);
+				int tag = pis.ReadByte();
+
+				if (tag < 0)
+					return null;
+
+				pis.Unread(tag);
+
+				if (tag != 0x30)	// assume ascii PEM encoded.
+				{
+					return ReadPemCrl(pis);
+				}
+
+				Asn1InputStream asn1 = lazyAsn1
+					?	new LazyAsn1InputStream(pis)
+					:	new Asn1InputStream(pis);
+
+				return ReadDerCrl(asn1);
+			}
+			catch (CrlException e)
+			{
+				throw e;
+			}
+			catch (Exception e)
+			{
+				throw new CrlException(e.ToString());
+			}
+		}
+
+		/**
+		 * Returns a (possibly empty) collection view of the CRLs read from
+		 * the given input stream inStream.
+		 *
+		 * The inStream may contain a sequence of DER-encoded CRLs, or
+		 * a PKCS#7 CRL set.  This is a PKCS#7 SignedData object, with the
+		 * only significant field being crls.  In particular the signature
+		 * and the contents are ignored.
+		 */
+		public ICollection ReadCrls(
+			Stream inStream)
+		{
+			X509Crl crl;
+			IList crls = new ArrayList();
+
+			while ((crl = ReadCrl(inStream)) != null)
+			{
+				crls.Add(crl);
+			}
+
+			return crls;
+		}
+	}
+}