public static Asn1TaggedObject GetInstance(
Asn1TaggedObject obj,
bool explicitly)
{
if (explicitly)
{
return (Asn1TaggedObject) obj.GetObject();
}
throw new ArgumentException("implicitly tagged tagged object");
}
public static DerGeneralString GetInstance(
Asn1TaggedObject obj,
bool isExplicit)
{
Asn1Object o = obj.GetObject();
if (isExplicit || o is DerGeneralString)
{
return GetInstance(o);
}
return new DerGeneralString(((Asn1OctetString)o).GetOctets());
}
/**
* return an Integer from a tagged object.
*
* @param obj the tagged object holding the object we want
* @param isExplicit true if the object is meant to be explicitly
* tagged false otherwise.
* @exception ArgumentException if the tagged object cannot
* be converted.
*/
public static DerInteger GetInstance(
Asn1TaggedObject obj,
bool isExplicit)
{
if (obj == null)
throw new ArgumentNullException("obj");
Asn1Object o = obj.GetObject();
if (isExplicit || o is DerInteger)
{
return GetInstance(o);
}
return new DerInteger(Asn1OctetString.GetInstance(o).GetOctets());
}
/**
* return a Visible string from a tagged object.
*
* @param obj the tagged object holding the object we want
* @param explicitly true if the object is meant to be explicitly
* tagged false otherwise.
* @exception ArgumentException if the tagged object cannot
* be converted.
*/
public static DerVisibleString GetInstance(
Asn1TaggedObject obj,
bool explicitly)
{
return GetInstance(obj.GetObject());
}
/**
* Return an ASN1 sequence from a tagged object. There is a special
* case here, if an object appears to have been explicitly tagged on
* reading but we were expecting it to be implicitly tagged in the
* normal course of events it indicates that we lost the surrounding
* sequence - so we need to add it back (this will happen if the tagged
* object is a sequence that contains other sequences). If you are
* dealing with implicitly tagged sequences you really <b>should</b>
* be using this method.
*
* @param obj the tagged object.
* @param explicitly true if the object is meant to be explicitly tagged,
* false otherwise.
* @exception ArgumentException if the tagged object cannot
* be converted.
*/
public static Asn1Sequence GetInstance(
Asn1TaggedObject obj,
bool explicitly)
{
Asn1Object inner = obj.GetObject();
if (explicitly)
{
if (!obj.IsExplicit())
throw new ArgumentException("object implicit - explicit expected.");
return (Asn1Sequence) inner;
}
//
// constructed object which appears to be explicitly tagged
// when it should be implicit means we have to add the
// surrounding sequence.
//
if (obj.IsExplicit())
{
if (obj is BerTaggedObject)
{
return new BerSequence(inner);
}
return new DerSequence(inner);
}
if (inner is Asn1Sequence)
{
return (Asn1Sequence) inner;
}
throw new ArgumentException("Unknown object in GetInstance: " + obj.GetType().FullName, "obj");
}
/**
* Return an ASN1 set from a tagged object. There is a special
* case here, if an object appears to have been explicitly tagged on
* reading but we were expecting it to be implicitly tagged in the
* normal course of events it indicates that we lost the surrounding
* set - so we need to add it back (this will happen if the tagged
* object is a sequence that contains other sequences). If you are
* dealing with implicitly tagged sets you really <b>should</b>
* be using this method.
*
* @param obj the tagged object.
* @param explicitly true if the object is meant to be explicitly tagged
* false otherwise.
* @exception ArgumentException if the tagged object cannot
* be converted.
*/
public static Asn1Set GetInstance(
Asn1TaggedObject obj,
bool explicitly)
{
Asn1Object inner = obj.GetObject();
if (explicitly)
{
if (!obj.IsExplicit())
throw new ArgumentException("object implicit - explicit expected.");
return (Asn1Set) inner;
}
//
// constructed object which appears to be explicitly tagged
// and it's really implicit means we have to add the
// surrounding sequence.
//
if (obj.IsExplicit())
{
return new DerSet(inner);
}
if (inner is Asn1Set)
{
return (Asn1Set) inner;
}
//
// in this case the parser returns a sequence, convert it
// into a set.
//
if (inner is Asn1Sequence)
{
Asn1EncodableVector v = new Asn1EncodableVector();
Asn1Sequence s = (Asn1Sequence) inner;
foreach (Asn1Encodable ae in s)
{
v.Add(ae);
}
// TODO Should be able to construct set directly from sequence?
return new DerSet(v, false);
}
throw new ArgumentException("Unknown object in GetInstance: " + obj.GetType().FullName, "obj");
}
/**
* return an object Identifier from a tagged object.
*
* @param obj the tagged object holding the object we want
* @param explicitly true if the object is meant to be explicitly
* tagged false otherwise.
* @exception ArgumentException if the tagged object cannot
* be converted.
*/
public static DerObjectIdentifier GetInstance(
Asn1TaggedObject obj,
bool explicitly)
{
return GetInstance(obj.GetObject());
}
