private static DecodedObjectMeta DecodeIdentifier(byte[] berBytes)
{
var decodedMeta = new DecodedObjectMeta();
var identifierOctet = berBytes[0];
if ((identifierOctet & 1 << 7) == 0)
{
decodedMeta.Class = (identifierOctet & 1 << 6) == 0
? SmiParser.Model.SmiEnums.DataTypeScope.UNIVERSAL
: SmiParser.Model.SmiEnums.DataTypeScope.APPLICATION;
}
else
{
decodedMeta.Class = (identifierOctet & 1 << 6) == 0
? SmiParser.Model.SmiEnums.DataTypeScope.CONTEXT_SPECIFIC
: SmiParser.Model.SmiEnums.DataTypeScope.PRIVATE;
}
decodedMeta.Constructed = (identifierOctet & 1 << 5) != 0;
decodedMeta.Tag = identifierOctet & 31;
return(decodedMeta);
}
private static List <DecodedObjectMeta> DecodeObjects(byte[] bytes)
{
List <DecodedObjectMeta> decodedList = new List <DecodedObjectMeta>();
if (bytes.Any())
{
DecodedObjectMeta decodedMeta = DecodeIdentifier(bytes);
DecodeLength(bytes, out var length, out var dataStart);
decodedMeta.ValueLength = length;
decodedMeta.ValueBytes = bytes.Skip(dataStart).Take((int)length).ToArray();
if (decodedMeta.Constructed)
{
decodedMeta.Children = DecodeObjects(
bytes
.Skip(dataStart)
.Take((int)length)
.ToArray()
);
foreach (DecodedObjectMeta child in decodedMeta.Children)
{
child.Parent = decodedMeta;
}
}
else
{
decodedMeta.Children = new List <DecodedObjectMeta>();
}
decodedList.Add(decodedMeta);
byte[] remainingBytes = bytes.Skip(dataStart + (int)length).ToArray();
decodedList.AddRange(DecodeObjects(remainingBytes));
}
return(decodedList);
}