/// <summary>
/// Decodes a ASN.1-encoded byte array that contains revoked certificate information to a collection.
/// </summary>
/// <param name="asn">ASN.1 that points to the beginning of the CRL entry collection structure.</param>
/// <exception cref="Asn1InvalidTagException">The encoded data is not valid.</exception>
/// <exception cref="ArgumentNullException">The <strong>rawData</strong> parameter is null reference.</exception>
/// <remarks>This method removes any existing entries in the collection before decoding.</remarks>
public void Decode(Asn1Reader asn)
{
if (asn == null)
{
throw new ArgumentNullException(nameof(asn));
}
if (asn.Tag != 48)
{
throw new Asn1InvalidTagException(asn.Offset);
}
Int32 offset = asn.Offset;
InternalList.Clear();
InternalList.Capacity = asn.GetNestedNodeCount();
if (!asn.MoveNext())
{
throw new Asn1InvalidTagException(asn.Offset);
}
do
{
InternalList.Add(new X509CRLEntry(asn));
} while (asn.MoveNextSibling());
asn.Seek(offset);
}
void decode(Asn1Reader asn)
{
if (asn.Tag != 48)
{
throw new Asn1InvalidTagException(asn.Offset);
}
RawData = asn.GetTagRawData();
Int32 offset = asn.Offset;
asn.MoveNext();
SerialNumber = Asn1Utils.DecodeInteger(asn.GetTagRawData(), true);
asn.MoveNextAndExpectTags(Asn1Type.UTCTime, Asn1Type.GeneralizedTime);
switch (asn.Tag)
{
case (Byte)Asn1Type.UTCTime:
RevocationDate = new Asn1UtcTime(asn.GetTagRawData()).Value;
break;
case (Byte)Asn1Type.GeneralizedTime:
RevocationDate = Asn1Utils.DecodeGeneralizedTime(asn.GetTagRawData());
break;
}
if (asn.MoveNextSibling())
{
// use high-performant extension decoder instead of generic one.
// Since CRLs may store a hundreds of thousands entries, this is
// pretty reasonable to save loops whenever possible.
readCrlReasonCode(asn);
}
asn.Seek(offset);
}
void readCrlReasonCode(Asn1Reader asn)
{
if (asn.Tag != 48)
{
return;
}
asn.MoveNext();
do
{
Int32 offset = asn.Offset;
asn.MoveNextAndExpectTags(Asn1Type.OBJECT_IDENTIFIER);
var oid = new Asn1ObjectIdentifier(asn).Value;
if (oid.Value == X509ExtensionOid.CRLReasonCode)
{
asn.MoveNext();
if (asn.Tag == (Byte)Asn1Type.BOOLEAN)
{
asn.MoveNext();
}
if (asn.Tag == (Byte)Asn1Type.OCTET_STRING)
{
asn.MoveNext();
if (asn.PayloadLength > 0)
{
ReasonCode = asn[asn.PayloadStartOffset];
break;
}
}
}
asn.Seek(offset);
} while (asn.MoveNextSibling());
}
/// <summary>
/// Decodes ASN.1-encoded byte array to an instance of <see cref="X509Extension"/> class.
/// </summary>
/// <param name="asn">ASN.1 reader that points to the beginning of the X.509 extension structure.</param>
/// <exception cref="ArgumentNullException"><strong>asn</strong> parameter is null.</exception>
/// <exception cref="Asn1InvalidTagException">Decoder encountered an unexpected ASN.1 type identifier.</exception>
/// <returns>Decoded extension object.</returns>
public static X509Extension Decode(Asn1Reader asn)
{
if (asn.Tag != 48)
{
throw new Asn1InvalidTagException(asn.Offset);
}
Int32 offset = asn.Offset;
asn.MoveNextAndExpectTags((Byte)Asn1Type.OBJECT_IDENTIFIER);
Oid oid = new Asn1ObjectIdentifier(asn).Value;
Boolean critical = false;
asn.MoveNextAndExpectTags((Byte)Asn1Type.BOOLEAN, (Byte)Asn1Type.OCTET_STRING);
if (asn.Tag == (Byte)Asn1Type.BOOLEAN)
{
critical = Asn1Utils.DecodeBoolean(asn.GetTagRawData());
asn.MoveNextAndExpectTags((Byte)Asn1Type.OCTET_STRING);
}
// at this point ASN points to OCTET_STRING
X509Extension retValue = new X509Extension(oid, asn.GetPayload(), critical).ConvertExtension();
asn.Seek(offset);
return(retValue);
}
/// <summary>
/// Decodes ASN.1-encoded byte array that represents a collection of <see cref="X509Extension"/> objects.
/// </summary>
/// <param name="extensions">Destination collection where decoded extensions will be added.</param>
/// <param name="asn">ASN.1 reader which points to the beginning of the extenstion collection structure.</param>
/// <exception cref="Asn1InvalidTagException">Decoder encountered an unexpected ASN.1 type identifier.</exception>
/// <exception cref="ArgumentNullException">
/// <strong>extensions</strong> and/or <strong>asn</strong> parameter is null.
/// </exception>
/// <remarks> If current collection contains items, decoded items will be appended to existing items.</remarks>
public static void Decode(this X509ExtensionCollection extensions, Asn1Reader asn)
{
if (extensions == null)
{
throw new ArgumentNullException(nameof(extensions));
}
if (asn == null)
{
throw new ArgumentNullException(nameof(asn));
}
Int32 offset = asn.Offset;
if (!asn.MoveNext() || asn.PayloadLength == 0)
{
return;
}
do
{
extensions.Add(X509ExtensionExtensions.Decode(asn));
} while (asn.MoveNextSibling());
asn.Seek(offset);
}