private static TagValueNode SimplifyTag(TagValueNode node)
{
if (node.Tag.IsExplicit())
{
EXPLICITTag exTag = node.Tag as EXPLICITTag;
SimpleASN1TAG smTag = exTag.ExtractSimpleOuterTag();
node.Tag = exTag.underTag;
TagValueNode tmpNode = SimplifyTag(node);
// node := (novi node)->node...
ArrayList nodes = new ArrayList();
nodes.Add(node);
return Create(smTag, nodes);
}
if (node.Tag.IsImplicit())
{
IMPLICITTag imTag = node.Tag as IMPLICITTag;
SimpleASN1TAG smTag = imTag.ExtractSimpleOuterTag();
node.Tag = imTag.underTag;
node = SimplifyTag(node);
node.Tag = smTag;
return node;
}
return null;
}
public void DumpNodeToStream(TagValueNode node)
{
binWriter.Write(node.TagOctets_);
binWriter.Write(node.LengthOctets_);
if (node.IsLeaf())
{
binWriter.Write(node.ValueOctets_);
}
else
{
foreach (TagValueNode nod in node.Nodes)
{
DumpNodeToStream(nod);
}
}
}
/// <summary>
/// <para>
/// This method traverses TagValue tree and expands all explicit and implicit tags and
/// turns them into simple tags.
/// </para>
/// <para>
/// This is preparation before binary dump. There are no length octets - but now
/// when all value octets are expanded they can be easily calculated on the fly.</para>
/// </summary>
/// <param name="node">a node representing a TagValue tree</param>
/// <returns>expanded corresponding tree</returns>
public static TagValueNode Expand(TagValueNode node)
{
if (!node.Tag.IsSimple()) { node = SimplifyTag(node); }
if (node.IsLeaf())
{
node.innerLen = node.ValueOctets.Length;
}
else
{
int valueLength = 0;
for(int i=0; i<node.Nodes.Count; i++)
{
node.Nodes[i] = Expand(node.Nodes[i] as TagValueNode);
valueLength += (node.Nodes[i] as TagValueNode).outerLen;
}
node.innerLen = valueLength;
}
/// FinishUpNode...
/// begin
node.LengthOctets = DERMethods.MakeLengthOctets(node.innerLen);
node.TagOctets = DERMethods.MakeTagOctets(node.Tag as SimpleASN1TAG);
node.outerLen = node.innerLen + node.LengthOctets.Length + node.TagOctets.Length;
/// end
return node;
}