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use std::collections::HashMap;
#[macro_use]
extern crate arrayref;
extern crate tiny_keccak;
extern crate rustc_hex;
mod utils;
mod node;
const TYPENODEEMPTY: u8 = 0;
const TYPENODENORMAL: u8 = 1;
const TYPENODEFINAL: u8 = 2;
const TYPENODEVALUE: u8 = 3;
const EMPTYNODEVALUE: [u8;32] = [0;32];
pub struct TestValue {
bytes: Vec<u8>,
index_length: u32,
}
pub trait Value {
fn bytes(&self) -> &Vec<u8>;
fn index_length(&self) -> u32;
}
impl Value for TestValue {
fn bytes(&self) -> &Vec<u8> {
&self.bytes
}
fn index_length(&self) -> u32 {
self.index_length
}
}
#[allow(dead_code)]
pub struct Db {
storage: HashMap<[u8;32], Vec<u8>>,
}
impl Db {
pub fn insert(&mut self, k: [u8; 32], t: u8, il: u32, b: &mut Vec<u8>) {
let mut v: Vec<u8>;
v = [t].to_vec();
let il_bytes = il.to_le_bytes();
v.append(&mut il_bytes.to_vec()); // il_bytes are [u8;4] (4 bytes)
v.append(b);
self.storage.insert(k, v);
}
pub fn get(&self, k: &[u8;32]) -> (u8, u32, Vec<u8>) {
if k.to_vec() == EMPTYNODEVALUE.to_vec() {
return (0, 0, EMPTYNODEVALUE.to_vec());
}
match self.storage.get(k) {
Some(x) => {
let t = x[0];
let il_bytes: [u8; 4] = [x[1], x[2], x[3], x[4]];
let il = u32::from_le_bytes(il_bytes);
let b = &x[5..];
return (t, il, b.to_vec());
},
None => return (TYPENODEEMPTY, 0, EMPTYNODEVALUE.to_vec()),
}
}
}
pub fn new_db()-> Db {
let db = Db {
storage: HashMap::new(),
};
db
}
pub struct MerkleTree {
#[allow(dead_code)]
root: [u8; 32],
#[allow(dead_code)]
num_levels: u32,
#[allow(dead_code)]
sto: Db,
}
pub fn new(num_levels: u32) -> MerkleTree {
let mt = MerkleTree {
root: EMPTYNODEVALUE,
num_levels: num_levels,
sto: new_db(),
};
mt
}
impl MerkleTree {
pub fn add(&mut self, v: &TestValue) {
#![allow(unused_variables)]
#[allow(dead_code)]
// println!("adding value: {:?}", v.bytes());
// add the leaf that we are adding
self.sto.insert(utils::hash_vec(v.bytes().to_vec()), TYPENODEVALUE, v.index_length(), &mut v.bytes().to_vec());
let index = v.index_length() as usize;
let hi = utils::hash_vec(v.bytes()[..index].to_vec());
let ht = utils::hash_vec(v.bytes().to_vec());
let path = utils::get_path(self.num_levels, hi);
let mut siblings: Vec<[u8;32]> = Vec::new();
let mut node_hash = self.root;
for i in (0..self.num_levels-1).rev() {
// get node
// let (t, il, node_bytes) = self.sto.get(&utils::hash_vec(node_hash.to_vec()));
let (t, il, node_bytes) = self.sto.get(&node_hash);
if t == TYPENODEFINAL {
let hi_child = utils::hash_vec(node_bytes.to_vec().split_at(il as usize).0.to_vec());
let path_child = utils::get_path(self.num_levels, hi_child);
let pos_diff = utils::compare_paths(path_child.clone(), path.clone());
if pos_diff == 999 { // TODO use a match here, and instead of 999 return something better
println!("compare paths err");
return;
}
let final_node_1_hash = utils::calc_hash_from_leaf_and_level(pos_diff, path_child.clone(), utils::hash_vec(node_bytes.to_vec()));
self.sto.insert(final_node_1_hash, TYPENODEFINAL, il, &mut node_bytes.to_vec());
let final_node_2_hash = utils::calc_hash_from_leaf_and_level(pos_diff, path.clone(), utils::hash_vec(v.bytes().to_vec()));
self.sto.insert(final_node_2_hash, TYPENODEFINAL, v.index_length(), &mut v.bytes().to_vec());
// parent node
let parent_node: node::TreeNode;
if path[pos_diff as usize] {
parent_node = node::TreeNode {
child_l: final_node_1_hash,
child_r: final_node_2_hash,
};
} else {
parent_node = node::TreeNode {
child_l: final_node_2_hash,
child_r: final_node_1_hash,
};
}
let empties = utils::get_empties_between_i_and_pos(i, pos_diff+1);
for j in 0..empties.len() {
siblings.push(empties[j]);
}
let path_from_pos_diff = utils::cut_path(path.clone(), (pos_diff +1) as usize);
self.root = self.replace_leaf(path_from_pos_diff, siblings.clone(), parent_node.ht(), TYPENODENORMAL, 0, &mut parent_node.bytes().to_vec());
return;
}
let node = node::parse_node_bytes(node_bytes);
let sibling: [u8;32];
if path.clone().into_iter().nth(i as usize).unwrap() {
node_hash = node.child_l;
sibling = node.child_r;
} else {
sibling = node.child_l;
node_hash = node.child_r;
}
siblings.push(*array_ref!(sibling, 0, 32));
if node_hash == EMPTYNODEVALUE {
if i==self.num_levels-2 && siblings[siblings.len()-1]==EMPTYNODEVALUE {
let final_node_hash = utils::calc_hash_from_leaf_and_level(i+1, path.clone(), utils::hash_vec(v.bytes().to_vec()));
self.sto.insert(final_node_hash, TYPENODEFINAL, v.index_length(), &mut v.bytes().to_vec());
self.root = final_node_hash;
return;
}
let final_node_hash = utils::calc_hash_from_leaf_and_level(i, path.clone(), utils::hash_vec(v.bytes().to_vec()));
let path_from_i = utils::cut_path(path.clone(), i as usize);
self.root = self.replace_leaf(path_from_i, siblings.clone(), final_node_hash, TYPENODEFINAL, v.index_length(), &mut v.bytes().to_vec());
return;
}
}
self.root = self.replace_leaf(path, siblings, utils::hash_vec(v.bytes().to_vec()), TYPENODEVALUE, v.index_length(), &mut v.bytes().to_vec());
}
#[allow(dead_code)]
pub fn replace_leaf(&mut self, path: Vec<bool>, siblings: Vec<[u8;32]>, leaf_hash: [u8;32], node_type: u8, index_length: u32, leaf_value: &mut Vec<u8>) -> [u8;32] {
self.sto.insert(leaf_hash, node_type, index_length, leaf_value);
let mut curr_node = leaf_hash;
for i in 0..siblings.len() {
if path.clone().into_iter().nth(i as usize).unwrap() {
let node = node::TreeNode {
child_l: curr_node,
child_r: siblings[siblings.len()-1-i],
};
self.sto.insert(node.ht(), TYPENODENORMAL, 0, &mut node.bytes());
curr_node = node.ht();
} else {
let node = node::TreeNode {
child_l: siblings[siblings.len()-1-i],
child_r: curr_node,
};
self.sto.insert(node.ht(), TYPENODENORMAL, 0, &mut node.bytes());
curr_node = node.ht();
}
}
curr_node
}
#[allow(dead_code)]
pub fn get_value_in_pos(&self, hi: [u8;32]) -> Vec<u8> {
let path = utils::get_path(self.num_levels, hi);
let mut node_hash = self.root;
for i in (0..self.num_levels-1).rev() {
let (t, il, node_bytes) = self.sto.get(&node_hash);
if t == TYPENODEFINAL {
let hi_node = utils::hash_vec(node_bytes.to_vec().split_at(il as usize).0.to_vec());
let path_node = utils::get_path(self.num_levels, hi_node);
let pos_diff = utils::compare_paths(path_node.clone(), path.clone());
// if pos_diff > self.num_levels {
if pos_diff != 999 {
return EMPTYNODEVALUE.to_vec();
}
return node_bytes;
}
let node = node::parse_node_bytes(node_bytes);
if !path.clone().into_iter().nth(i as usize).unwrap() {
node_hash = node.child_l;
} else {
node_hash = node.child_r;
}
}
let (_t, _il, node_bytes) = self.sto.get(&node_hash);
node_bytes
}
#[allow(dead_code)]
pub fn generate_proof(&self, hi: [u8;32]) -> Vec<u8> {
let mut mp: Vec<u8> = Vec::new();
let mut empties: [u8;32] = [0;32];
let path = utils::get_path(self.num_levels, hi);
let mut siblings: Vec<[u8;32]> = Vec::new();
let mut node_hash = self.root;
for i in 0..self.num_levels {
let (t, il, node_bytes) = self.sto.get(&node_hash);
if t == TYPENODEFINAL {
let real_value_in_pos = self.get_value_in_pos(hi);
if real_value_in_pos == EMPTYNODEVALUE {
let leaf_hi = utils::hash_vec(node_bytes.to_vec().split_at(il as usize).0.to_vec());
let path_child = utils::get_path(self.num_levels, leaf_hi);
let pos_diff = utils::compare_paths(path_child.clone(), path.clone());
if pos_diff == self.num_levels { // TODO use a match here, and instead of 999 return something better
return mp;
}
if pos_diff != self.num_levels-1-i {
let sibling = utils::calc_hash_from_leaf_and_level(pos_diff, path_child.clone(), utils::hash_vec(node_bytes.to_vec()));
let mut new_siblings: Vec<[u8;32]> = Vec::new();
new_siblings.push(sibling);
new_siblings.append(&mut siblings);
siblings = new_siblings;
// set empties bit
let bit_pos = self.num_levels-2-pos_diff;
empties[(empties.len() as isize + (bit_pos as isize/8-1) as isize) as usize] |= 1 << bit_pos%8;
}
}
break
}
let node = node::parse_node_bytes(node_bytes);
let sibling: [u8;32];
if !path.clone().into_iter().nth(self.num_levels as usize -i as usize-2 as usize).unwrap() {
node_hash = node.child_l;
sibling = node.child_r;
} else {
sibling = node.child_l;
node_hash = node.child_r;
}
if sibling != EMPTYNODEVALUE {
// set empties bit
empties[(empties.len() as isize + (i as isize/8-1) as isize) as usize] |= 1 << i%8;
let mut new_siblings: Vec<[u8;32]> = Vec::new();
new_siblings.push(sibling);
new_siblings.append(&mut siblings);
siblings = new_siblings;
}
}
mp.append(&mut empties[..].to_vec());
for s in siblings {
mp.append(&mut s.to_vec());
}
mp
}
}
#[cfg(test)]
mod tests {
use super::*;
use rustc_hex::ToHex;
#[test]
fn test_hash_vec() {
let a: Vec<u8> = From::from("test");
let h = utils::hash_vec(a);
assert_eq!("9c22ff5f21f0b81b113e63f7db6da94fedef11b2119b4088b89664fb9a3cb658", h.to_hex());
}
#[test]
fn test_new_mt() {
let mt: MerkleTree = new(140);
assert_eq!(140, mt.num_levels);
assert_eq!("0000000000000000000000000000000000000000000000000000000000000000", mt.root.to_hex());
let (_t, _il, b) = mt.sto.get(&[0;32]);
assert_eq!(mt.root.to_vec(), b);
}
#[test]
fn test_tree_node() {
let n = node::TreeNode {
child_l: [1;32],
child_r: [2;32],
};
assert_eq!("01010101010101010101010101010101010101010101010101010101010101010202020202020202020202020202020202020202020202020202020202020202",
n.bytes().to_hex());
assert_eq!("346d8c96a2454213fcc0daff3c96ad0398148181b9fa6488f7ae2c0af5b20aa0", n.ht().to_hex());
}
#[test]
fn test_add() {
let mut mt: MerkleTree = new(140);
assert_eq!("0000000000000000000000000000000000000000000000000000000000000000", mt.root.to_hex());
let val = TestValue {
bytes: vec![1,2,3,4,5],
index_length: 3,
};
mt.add(&val);
let (_t, _il, b) = mt.sto.get(&utils::hash_vec(val.bytes().to_vec()));
assert_eq!(*val.bytes(), b);
assert_eq!("a0e72cc948119fcb71b413cf5ada12b2b825d5133299b20a6d9325ffc3e2fbf1", mt.root.to_hex());
}
#[test]
fn test_add_2() {
let mut mt: MerkleTree = new(140);
let val = TestValue {
bytes: "this is a test leaf".as_bytes().to_vec(),
index_length: 15,
};
assert_eq!("0000000000000000000000000000000000000000000000000000000000000000", mt.root.to_hex());
mt.add(&val);
let (_t, _il, b) = mt.sto.get(&utils::hash_vec(val.bytes().to_vec()));
assert_eq!(*val.bytes(), b);
assert_eq!("b4fdf8a653198f0e179ccb3af7e4fc09d76247f479d6cfc95cd92d6fda589f27", mt.root.to_hex());
let val2 = TestValue {
bytes: "this is a second test leaf".as_bytes().to_vec(),
index_length: 15,
};
mt.add(&val2);
let (_t, _il, b) = mt.sto.get(&utils::hash_vec(val2.bytes().to_vec()));
assert_eq!(*val2.bytes(), b);
assert_eq!("8ac95e9c8a6fbd40bb21de7895ee35f9c8f30ca029dbb0972c02344f49462e82", mt.root.to_hex());
}
#[test]
fn test_generate_proof() {
let mut mt: MerkleTree = new(140);
let val = TestValue {
bytes: "this is a test leaf".as_bytes().to_vec(),
index_length: 15,
};
assert_eq!("0000000000000000000000000000000000000000000000000000000000000000", mt.root.to_hex());
mt.add(&val);
let (_t, _il, b) = mt.sto.get(&utils::hash_vec(val.bytes().to_vec()));
assert_eq!(*val.bytes(), b);
assert_eq!("b4fdf8a653198f0e179ccb3af7e4fc09d76247f479d6cfc95cd92d6fda589f27", mt.root.to_hex());
let val2 = TestValue {
bytes: "this is a second test leaf".as_bytes().to_vec(),
index_length: 15,
};
mt.add(&val2);
let (_t, _il, b) = mt.sto.get(&utils::hash_vec(val2.bytes().to_vec()));
assert_eq!(*val2.bytes(), b);
assert_eq!("8ac95e9c8a6fbd40bb21de7895ee35f9c8f30ca029dbb0972c02344f49462e82", mt.root.to_hex());
let hi = utils::hash_vec(val2.bytes().to_vec().split_at(val2.index_length as usize).0.to_vec());
let mp = mt.generate_proof(hi);
assert_eq!("0000000000000000000000000000000000000000000000000000000000000001fd8e1a60cdb23c0c7b2cf8462c99fafd905054dccb0ed75e7c8a7d6806749b6b", mp.to_hex())
}
#[test]
fn test_generate_proof_empty_leaf() {
let mut mt: MerkleTree = new(140);
let val = TestValue {
bytes: "this is a test leaf".as_bytes().to_vec(),
index_length: 15,
};
mt.add(&val);
let val2 = TestValue {
bytes: "this is a second test leaf".as_bytes().to_vec(),
index_length: 15,
};
mt.add(&val2);
assert_eq!("8ac95e9c8a6fbd40bb21de7895ee35f9c8f30ca029dbb0972c02344f49462e82", mt.root.to_hex());
// proof of empty leaf
let val3 = TestValue {
bytes: "this is a third test leaf".as_bytes().to_vec(),
index_length: 15,
};
let hi = utils::hash_vec(val3.bytes().to_vec().split_at(val3.index_length as usize).0.to_vec());
let mp = mt.generate_proof(hi);
assert_eq!("000000000000000000000000000000000000000000000000000000000000000389741fa23da77c259781ad8f4331a5a7d793eef1db7e5200ddfc8e5f5ca7ce2bfd8e1a60cdb23c0c7b2cf8462c99fafd905054dccb0ed75e7c8a7d6806749b6b", mp.to_hex())
}
}
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