private BEROctetString buildConstructedOctetString()
{
ArrayList octs = new ArrayList();
for (;;)
{
ASN1Object o = readObject();
if (o == END_OF_STREAM)
{
break;
}
octs.Add(o);
}
return(new BEROctetString(octs));
}
public BEROctetString(ASN1Object obj) : base(obj)
{
}
public ASN1Object readObject()
{
int tag = ReadByte();
if (tag == -1)
{
if (eofFound)
{
throw new EndOfStreamException("attempt to read past end of file.");
}
eofFound = true;
return(null);
}
int length = readLength();
if (length < 0) // indefinite length method
{
switch (tag)
{
case ASN1Tags.NULL:
return(new BERNull());
case ASN1Tags.SEQUENCE | ASN1Tags.CONSTRUCTED:
ASN1EncodableVector v = new ASN1EncodableVector();
for (;;)
{
ASN1Object obj = readObject();
if (obj == END_OF_STREAM)
{
break;
}
v.add(obj);
}
return(new BERSequence(v));
case ASN1Tags.SET | ASN1Tags.CONSTRUCTED:
v = new ASN1EncodableVector();
for (;;)
{
ASN1Object obj = readObject();
if (obj == END_OF_STREAM)
{
break;
}
v.add(obj);
}
return(new BERSet(v, false));
case ASN1Tags.OCTET_STRING | ASN1Tags.CONSTRUCTED:
return(buildConstructedOctetString());
default:
//
// with tagged object tag number is bottom 5 bits
//
if ((tag & (int)ASN1Tags.TAGGED) != 0)
{
int tagNo = tag & 0x1f;
if (tagNo == 0x1f)
{
int b = ReadByte();
tagNo = 0;
while ((b >= 0) && ((b & 0x80) != 0))
{
tagNo |= (b & 0x7f);
tagNo <<= 7;
b = ReadByte();
}
tagNo |= (b & 0x7f);
}
//
// simple type - implicit... return an octet string
//
if ((tag & (int)ASN1Tags.CONSTRUCTED) == 0)
{
byte[] bytes = readIndefiniteLengthFully();
return(new BERTaggedObject(false, tagNo, new DEROctetString(bytes)));
}
//
// either constructed or explicitly tagged
//
ASN1Object dObj = readObject();
if (dObj == END_OF_STREAM) // empty tag!
{
return(new DERTaggedObject(tagNo));
}
ASN1Object next = readObject();
//
// explicitly tagged (probably!) - if it isn't we'd have to
// tell from the context
//
if (next == END_OF_STREAM)
{
return(new BERTaggedObject(tagNo, dObj));
}
//
// another implicit object, we'll create a sequence...
//
v = new ASN1EncodableVector();
v.add(dObj);
do
{
v.add(next);
next = readObject();
}while (next != END_OF_STREAM);
return(new BERTaggedObject(false, tagNo, new BERSequence(v)));
}
throw new IOException("unknown BER object encountered");
}
}
else
{
if (tag == 0 && length == 0) // end of contents marker.
{
return(END_OF_STREAM);
}
byte[] bytes = new byte[length];
readFully(bytes);
return(buildObject(tag, bytes));
}
}
/**
* build an object given its tag and a byte stream to construct it
* from.
*/
protected ASN1Object buildObject(
int derTags,
byte[] bytes)
{
int tag = derTags;
if ((tag & ASN1Tags.APPLICATION) != 0)
{
return(new DERApplicationSpecific(derTags, bytes));
}
switch (tag)
{
case ASN1Tags.NULL:
return(new DERNull());
case ASN1Tags.SEQUENCE | ASN1Tags.CONSTRUCTED:
MemoryStream bIn = new MemoryStream(bytes);
ASN1InputStream aIn = new ASN1InputStream(bIn);
ASN1EncodableVector v = new ASN1EncodableVector();
ASN1Object obj = aIn.readObject();
while (obj != null)
{
v.add(obj);
obj = aIn.readObject();
}
return(new DERSequence(v));
case ASN1Tags.SET | ASN1Tags.CONSTRUCTED:
bIn = new MemoryStream(bytes);
aIn = new ASN1InputStream(bIn);
v = new ASN1EncodableVector();
obj = aIn.readObject();
while (obj != null)
{
v.add(obj);
obj = aIn.readObject();
}
return(new DERSet(v, false));
case ASN1Tags.BOOLEAN:
return(new DERBoolean(bytes));
case ASN1Tags.INTEGER:
return(new DERInteger(bytes));
case ASN1Tags.ENUMERATED:
return(new DEREnumerated(bytes));
case ASN1Tags.OBJECT_IDENTIFIER:
return(new DERObjectIdentifier(bytes));
case ASN1Tags.BIT_STRING:
int padBits = bytes[0];
byte[] data = new byte[bytes.Length - 1];
Array.Copy(bytes, 1, data, 0, bytes.Length - 1);
return(new DERBitString(data, padBits));
case ASN1Tags.NUMERIC_STRING:
return(new DERNumericString(bytes));
case ASN1Tags.UTF8_STRING:
return(new DERUTF8String(bytes));
case ASN1Tags.PRINTABLE_STRING:
return(new DERPrintableString(bytes));
case ASN1Tags.IA5_STRING:
return(new DERIA5String(bytes));
case ASN1Tags.T61_STRING:
return(new DERT61String(bytes));
case ASN1Tags.VISIBLE_STRING:
return(new DERVisibleString(bytes));
case ASN1Tags.GENERAL_STRING:
return(new DERGeneralString(bytes));
case ASN1Tags.UNIVERSAL_STRING:
return(new DERUniversalString(bytes));
case ASN1Tags.BMP_STRING:
return(new DERBMPString(bytes));
case ASN1Tags.OCTET_STRING:
return(new DEROctetString(bytes));
case ASN1Tags.UTC_TIME:
return(new DERUTCTime(bytes));
case ASN1Tags.GENERALIZED_TIME:
return(new DERGeneralizedTime(bytes));
default:
//
// with tagged object tag number is bottom 5 bits
//
if ((tag & (int)ASN1Tags.TAGGED) != 0)
{
int tagNo = tag & 0x1f;
if (tagNo == 0x1f)
{
int idx = 0;
tagNo = 0;
while ((bytes[idx] & 0x80) != 0)
{
tagNo |= (bytes[idx++] & 0x7f);
tagNo <<= 7;
}
tagNo |= (bytes[idx] & 0x7f);
byte[] tmp = bytes;
bytes = new byte[tmp.Length - (idx + 1)];
Array.Copy(tmp, idx + 1, bytes, 0, bytes.Length);
}
if (bytes.Length == 0) // empty tag!
{
if ((tag & (int)ASN1Tags.CONSTRUCTED) == 0)
{
return(new DERTaggedObject(false, tagNo, new DERNull()));
}
else
{
return(new DERTaggedObject(false, tagNo, new DERSequence()));
}
}
//
// simple type - implicit... return an octet string
//
if ((tag & (int)ASN1Tags.CONSTRUCTED) == 0)
{
return(new DERTaggedObject(false, tagNo, new DEROctetString(bytes)));
}
bIn = new MemoryStream(bytes);
aIn = new ASN1InputStream(bIn);
ASN1Encodable dObj = aIn.readObject();
//
// explicitly tagged (probably!) - if it isn't we'd have to
// tell from the context
//
// if (aIn.available() == 0)
if (aIn.Position == bytes.Length) //FIXME?
{
return(new DERTaggedObject(tagNo, dObj));
}
//
// another implicit object, we'll create a sequence...
//
v = new ASN1EncodableVector();
while (dObj != null)
{
v.add(dObj);
dObj = aIn.readObject();
}
return(new DERTaggedObject(false, tagNo, new DERSequence(v)));
}
return(new DERUnknownTag(tag, bytes));
}
}
