マークルツリーはリーフから上に向かって構築するため、構造を知るために必要なのは存在するリーフの数
from helper import hash256 class MerkleTree: def __init__(self, total): self.total = total self.max_depth = math.ceil(math.log(self.total, 2)) self.nodes = [] for depth in range(self.max_depth + 1): num_items = math.ceil(self.total / 2**(self.max_depth - depth)) level_hashes = [None] * num_items self.nodes.append(level_hashes) self.current_depth = 0 self.current_index = 0 def __repr__(self): result = [] for depth, level in enumerate(self.nodes): item = [] for index, h in enumerate(level): if h is None: short = 'None' else: short = '{}...'.format(h.hex()[:8]) if depth == self.current_depth and index == self.current_index: items.append('*{}*'.format(short[:-2])) else: items.append('{}'.format(short)) result.append(', '.join(items)) return '\n'.join(result)
from merkleblock import MerkleTree from helper import merkle_parent_level hex_hashes = [ "9745f7173ef14ee4155722d1cbf13304339fd00d900b759c6f9d58579b5765fb", "5573c8ede34936c29cdfdfe743f7f5fdfbd4f54ba0705259e62f39917065cb9b", "82a02ecbb6623b4274dfcab82b336dc017a27136e08521091e443e62582e8f05", "507ccae5ed9b340363a0e6d765af148be9cb1c8766ccc922f83e4ae681658308", "a7a4aec28e7162e1e9ef33dfa30f0bc0526e6cf4b11a576f6c5de58593898330", "bb6267664bd833fd9fc82582853ab144fece26b7a8a5bf328f8a059445b59add", "ea6d7ac1ee77fbacee58fc717b990c4fcccf1b19af43103c090f601677fd8836", "457743861de496c429912558a106b810b0507975a49773228aa788df40730d41", "7688029288efc9e9a0011c960a6ed9e5466581abf3e3a6c26ee317461add619a", "b1ae7f15836cb2286cdd4e2c37bf9bb7da0a2846d06867a429f654b2e7f383c9", "9b74f89fa3f93e71ff2c241f32945d877281a6a50a6bf94adac002980aafe5ab", "b3a92b5b255019bdaf754875633c2de9fec2ab03e6b8ce669d07cb5b18804638", "b5c0b915312b9bdaedd2b86aa2d0f8feffc73a2d37668fd9010179261e25e263", "c9d52c5cb1e557b92c84c52e7c4bfbce859408bedffc8a5560fd6e35e10b8800", "c555bc5fc3bc096df0a0c9532f07640bfb76bfe4fc1ace214b8b228a1297a4c2", "f9dbfafc3af3400954975da24eb325e326960a25b87fffe23eef3e7ed2fb610e", ] tree = MerkleTree(len(hex_hashes)) tree.nodes[4] = [bytes.fromhex(h) for h in hex_hashes] tree.nodes[3] = merkle_parent_level(tree.nodes[4]) tree.nodes[2] = merkle_parent_level(tree.nodes[3]) tree.nodes[1] = merkle_parent_level(tree.nodes[2]) tree.nodes[0] = merkle_parent_level(tree.nodes[1]) print(tree)
$ python3 test.py
*597c4baf.*
6382df3f…, 87cf8fa3…
3ba6c080…, 8e894862…, 7ab01bb6…, 3df760ac…
272945ec…, 9a38d037…, 4a64abd9…, ec7c95e1…, 3b67006c…, 850683df…, d40d268b…, 8636b7a3…
9745f717…, 5573c8ed…, 82a02ecb…, 507ccae5…, a7a4aec2…, bb626766…, ea6d7ac1…, 45774386…, 76880292…, b1ae7f15…, 9b74f89f…, b3a92b5b…, b5c0b915…, c9d52c5c…, c555bc5f…, f9dbfafc…
### Tree traversal
def up(self): self.current_depth -= 1 self.current_index //= 2 def left(self): self.current_depth += 1 self.current_index *= 2 def right(self): self.current_depth += 1 self.current_index = self.current_index * 2 + 1 def root(self): return self.node[0][0] def self_current_node(self): self.nodes[self.current_depth][self.current_index] = value def get_current_node(self): return self.nodes[self.current_depth][self.current_index] def get_left_node(self): return self.nodes[self.current_depth + 1][self.current_index * 2] def get_right_node(self): return self.nodes[self.current_depth + 1][self.current_index * 2 + 1] def is_leaf(self): return self.current_depth == self.max_depth def right_exists(self): return len(self.nodes[self.current_depth + 1]) > self.current_index * 2 + 1
from merkleblock import MerkleTree from helper import merkle_parent hex_hashes = [ "9745f7173ef14ee4155722d1cbf13304339fd00d900b759c6f9d58579b5765fb", "5573c8ede34936c29cdfdfe743f7f5fdfbd4f54ba0705259e62f39917065cb9b", "82a02ecbb6623b4274dfcab82b336dc017a27136e08521091e443e62582e8f05", "507ccae5ed9b340363a0e6d765af148be9cb1c8766ccc922f83e4ae681658308", "a7a4aec28e7162e1e9ef33dfa30f0bc0526e6cf4b11a576f6c5de58593898330", "bb6267664bd833fd9fc82582853ab144fece26b7a8a5bf328f8a059445b59add", "ea6d7ac1ee77fbacee58fc717b990c4fcccf1b19af43103c090f601677fd8836", "457743861de496c429912558a106b810b0507975a49773228aa788df40730d41", "7688029288efc9e9a0011c960a6ed9e5466581abf3e3a6c26ee317461add619a", "b1ae7f15836cb2286cdd4e2c37bf9bb7da0a2846d06867a429f654b2e7f383c9", "9b74f89fa3f93e71ff2c241f32945d877281a6a50a6bf94adac002980aafe5ab", "b3a92b5b255019bdaf754875633c2de9fec2ab03e6b8ce669d07cb5b18804638", "b5c0b915312b9bdaedd2b86aa2d0f8feffc73a2d37668fd9010179261e25e263", "c9d52c5cb1e557b92c84c52e7c4bfbce859408bedffc8a5560fd6e35e10b8800", "c555bc5fc3bc096df0a0c9532f07640bfb76bfe4fc1ace214b8b228a1297a4c2", "f9dbfafc3af3400954975da24eb325e326960a25b87fffe23eef3e7ed2fb610e", ] tree = MerkleTree(len(hex_hashes)) tree.nodes[4] = [bytes.fromhex(h) for h in hex_hashes] while tree.root() is None: if tree.is_leaf(): tree.up() else: left_hash = tree.get_left_node() right_hash = tree.get_right_node() if left_hash is None: tree.left() elif right_hash is None: tree.right() else: tree.set_current_node(merkle_parent(left_hash, right_hash)) tree.up() print(tree)
奇数の処理
L left_hash, left_hashとする
from merkleblock import MerkleTree from helper import merkle_parent hex_hashes = [ "9745f7173ef14ee4155722d1cbf13304339fd00d900b759c6f9d58579b5765fb", "5573c8ede34936c29cdfdfe743f7f5fdfbd4f54ba0705259e62f39917065cb9b", "82a02ecbb6623b4274dfcab82b336dc017a27136e08521091e443e62582e8f05", "507ccae5ed9b340363a0e6d765af148be9cb1c8766ccc922f83e4ae681658308", "a7a4aec28e7162e1e9ef33dfa30f0bc0526e6cf4b11a576f6c5de58593898330", "bb6267664bd833fd9fc82582853ab144fece26b7a8a5bf328f8a059445b59add", "ea6d7ac1ee77fbacee58fc717b990c4fcccf1b19af43103c090f601677fd8836", "457743861de496c429912558a106b810b0507975a49773228aa788df40730d41", "7688029288efc9e9a0011c960a6ed9e5466581abf3e3a6c26ee317461add619a", "b1ae7f15836cb2286cdd4e2c37bf9bb7da0a2846d06867a429f654b2e7f383c9", "9b74f89fa3f93e71ff2c241f32945d877281a6a50a6bf94adac002980aafe5ab", "b3a92b5b255019bdaf754875633c2de9fec2ab03e6b8ce669d07cb5b18804638", "b5c0b915312b9bdaedd2b86aa2d0f8feffc73a2d37668fd9010179261e25e263", "c9d52c5cb1e557b92c84c52e7c4bfbce859408bedffc8a5560fd6e35e10b8800", "c555bc5fc3bc096df0a0c9532f07640bfb76bfe4fc1ace214b8b228a1297a4c2", "f9dbfafc3af3400954975da24eb325e326960a25b87fffe23eef3e7ed2fb610e", "38faf8c811988dff0a7e6080b1771c97bcc0801c64d9068cffb85e6e7aacaf51", ] tree = MerkleTree(len(hex_hashes)) tree.nodes[5] = [bytes.fromhex(h) for h in hex_hashes] while tree.root() is None: if tree.is_leaf(): tree.up() else: left_hash = tree.get_left_node() if left_hash is None: tree.left() elif tree.right_exists(): right_hash = tree.get_right_node() if right_hash is None: tree.right() else: tree.set_current_node(merkle_parent(left_hash, right_hash)) tree.up() else: tree.set_current_node(merkle_parent(left_hash, left_hash)) tree.up()