def serialize_header(inp):
o = encode(inp['version'], 256, 4)[::-1] + \
unhexify(inp['prevhash'])[::-1] + \
unhexify(inp['merkle_root'])[::-1] + \
encode(inp['timestamp'], 256, 4)[::-1] + \
encode(inp['bits'], 256, 4)[::-1] + \
encode(inp['nonce'], 256, 4)[::-1]
h = hexify(bin_sha256(bin_sha256(o))[::-1])
assert h == inp['hash'], (sha256(o), inp['hash'])
return hexify(o)
def deserialize_header(inp):
inp = unhexify(inp)
return {
"version": decode(inp[:4][::-1], 256),
"prevhash": hexify(inp[4:36][::-1]),
"merkle_root": hexify(inp[36:68][::-1]),
"timestamp": decode(inp[68:72][::-1], 256),
"bits": decode(inp[72:76][::-1], 256),
"nonce": decode(inp[76:80][::-1], 256),
"hash": hexify(bin_sha256(bin_sha256(inp))[::-1])
}
def mk_merkle_proof(header, hashes, index):
nodes = [unhexify(h)[::-1] for h in hashes]
if len(nodes) % 2 and len(nodes) > 2:
nodes.append(nodes[-1])
layers = [nodes]
while len(nodes) > 1:
newnodes = []
for i in range(0, len(nodes) - 1, 2):
newnodes.append(bin_sha256(bin_sha256(nodes[i] + nodes[i+1])))
if len(newnodes) % 2 and len(newnodes) > 2:
newnodes.append(newnodes[-1])
nodes = newnodes
layers.append(nodes)
# Sanity check, make sure merkle root is valid
assert hexify(nodes[0][::-1]) == header['merkle_root']
merkle_siblings = \
[layers[i][(index >> i) ^ 1] for i in range(len(layers)-1)]
return {
"hash": hashes[index],
"siblings": [hexify(x[::-1]) for x in merkle_siblings],
"header": header
}