Class TreeHashInput

mlspp/src/treekem.cpp:818–1127

};

struct TreeHashInput
{
  var::variant<LeafNodeHashInput, ParentNodeHashInput> node;
  TLS_SERIALIZABLE(node);
  TLS_TRAITS(tls::variant<NodeType>)
};

const bytes&
TreeKEMPublicKey::get_hash(NodeIndex index)
{
  if (hashes.count(index) > 0) {
    return hashes.at(index);
  }

  auto hash_input = bytes{};
  const auto& node = node_at(index);
  if (index.level() == 0) {
    auto input = LeafNodeHashInput{ LeafIndex(index), {} };
    if (!node.blank()) {
      input.leaf_node = node.leaf_node();
    }

    hash_input = tls::marshal(TreeHashInput{ input });
  } else {
    auto input = ParentNodeHashInput{
      {},
      get_hash(index.left()),
      get_hash(index.right()),
    };

    if (!node.blank()) {
      input.parent_node = node.parent_node();
    }

    hash_input = tls::marshal(TreeHashInput{ input });
  }

  auto hash = suite.digest().hash(hash_input);
  hashes.insert_or_assign(index, hash);
  return hashes.at(index);
}

// struct {
//     HPKEPublicKey encryption_key;
//     opaque parent_hash<V>;
//     opaque original_sibling_tree_hash<V>;
// } ParentHashInput;
struct ParentHashInput
{
  const HPKEPublicKey& public_key;
  const bytes& parent_hash;
  const bytes& original_child_resolution;

  TLS_SERIALIZABLE(public_key, parent_hash, original_child_resolution)
};

bytes
TreeKEMPublicKey::parent_hash(const ParentNode& parent,