Initial Commit

iTechSharp/srcbc/asn1/x509/X509NameEntryConverter.cs

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+using System;
+using System.Globalization;
+using System.IO;
+using System.Text;
+
+using Org.BouncyCastle.Utilities.Encoders;
+
+namespace Org.BouncyCastle.Asn1.X509
+{
+    /**
+     * It turns out that the number of standard ways the fields in a DN should be
+     * encoded into their ASN.1 counterparts is rapidly approaching the
+     * number of machines on the internet. By default the X509Name class
+     * will produce UTF8Strings in line with the current recommendations (RFC 3280).
+     * <p>
+     * An example of an encoder look like below:
+     * <pre>
+     * public class X509DirEntryConverter
+     *     : X509NameEntryConverter
+     * {
+     *     public Asn1Object GetConvertedValue(
+     *         DerObjectIdentifier  oid,
+     *         string               value)
+     *     {
+     *         if (str.Length() != 0 &amp;&amp; str.charAt(0) == '#')
+     *         {
+     *             return ConvertHexEncoded(str, 1);
+     *         }
+     *         if (oid.Equals(EmailAddress))
+     *         {
+     *             return new DerIA5String(str);
+     *         }
+     *         else if (CanBePrintable(str))
+     *         {
+     *             return new DerPrintableString(str);
+     *         }
+     *         else if (CanBeUTF8(str))
+     *         {
+     *             return new DerUtf8String(str);
+     *         }
+     *         else
+     *         {
+     *             return new DerBmpString(str);
+     *         }
+     *     }
+     * }
+	 * </pre>
+	 * </p>
+     */
+    public abstract class X509NameEntryConverter
+    {
+        /**
+         * Convert an inline encoded hex string rendition of an ASN.1
+         * object back into its corresponding ASN.1 object.
+         *
+         * @param str the hex encoded object
+         * @param off the index at which the encoding starts
+         * @return the decoded object
+         */
+        protected Asn1Object ConvertHexEncoded(
+            string	hexString,
+            int		offset)
+        {
+			string str = hexString.Substring(offset);
+
+			return Asn1Object.FromByteArray(Hex.Decode(str));
+        }
+
+		/**
+         * return true if the passed in string can be represented without
+         * loss as a PrintableString, false otherwise.
+         */
+        protected bool CanBePrintable(
+            string str)
+        {
+			return DerPrintableString.IsPrintableString(str);
+        }
+
+		/**
+         * Convert the passed in string value into the appropriate ASN.1
+         * encoded object.
+         *
+         * @param oid the oid associated with the value in the DN.
+         * @param value the value of the particular DN component.
+         * @return the ASN.1 equivalent for the value.
+         */
+        public abstract Asn1Object GetConvertedValue(DerObjectIdentifier oid, string value);
+    }
+}