qyriad/miden-crypto
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

WIP: slightly refactor recompute_nodes_from_index_to_root()

Browse source
This commit is contained in:
Qyriad 2024-08-16 19:22:15 -06:00
parent d5250cd202
commit 2fac7f11d9
1 changed files with 19 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

30
src/merkle/smt/mod.rs
View file

@ -116,27 +116,24 @@ pub(crate) trait SparseMerkleTree<const DEPTH: u8> {
mut index: NodeIndex,
node_hash_at_index: RpoDigest,
) {
let mut node_hash = node_hash_at_index;
let mut new_child_hash = node_hash_at_index;
for node_depth in (0..index.depth()).rev() {
let is_right = index.is_value_odd();
index.move_up();
let InnerNode { left, right } = self.get_inner_node(index);
let (left, right) = if is_right {
(left, node_hash)
} else {
(node_hash, right)
};
node_hash = Rpo256::merge(&[left, right]);
let old_node = self.get_inner_node(index);
let new_node = old_node.create_update(is_right, new_child_hash);
new_child_hash = new_node.hash();
if node_hash == *EmptySubtreeRoots::entry(DEPTH, node_depth) {
let &equivalent_empty_hash = EmptySubtreeRoots::entry(DEPTH, node_depth);
if new_child_hash == equivalent_empty_hash {
// If a subtree is empty, when can remove the inner node, since it's equal to the
// default value
self.remove_inner_node(index)
} else {
self.insert_inner_node(index, InnerNode { left, right });
self.insert_inner_node(index, new_node);
}
}
self.set_root(node_hash);
self.set_root(new_child_hash);
}
// REQUIRED METHODS
@ -195,6 +192,17 @@ pub(crate) struct InnerNode {
}
impl InnerNode {
/// Creates a new node for when a child node has been changed.
pub fn create_update(self, update_right: bool, new_hash: RpoDigest) -> Self {
let (left, right) = if update_right {
(self.left, new_hash)
} else {
(new_hash, self.right)
};
Self { left, right }
}
pub fn hash(&self) -> RpoDigest {
Rpo256::merge(&[self.left, self.right])
}