def select_inputs(self):
assert self.stage is None, "Incorrect stage"
assert self.role == Role.SELLER, "Incorrect role"
self.stage = Stage.INIT
if self.is_bitcoin_swap():
# Generate a key that will co-sign the BTC multisig
self.swap_cosign = SecretKey.random(self.secp)
self.public_swap_cosign = self.swap_cosign.to_public_key(self.secp)
# Inputs
self.input_entries = self.wallet.select_outputs(
self.grin_amount + tx_fee(1, 2, MILLI_GRIN_UNIT) + 1)
self.inputs = []
for entry in self.input_entries:
entry.mark_locked()
input = self.wallet.entry_to_input(entry)
self.inputs.append(input)
self.fee_amount = tx_fee(len(self.input_entries), 2, MILLI_GRIN_UNIT)
self.refund_fee_amount = tx_fee(1, 1, MILLI_GRIN_UNIT)
self.input_amount = sum(x.value for x in self.input_entries)
self.change_amount = self.input_amount - self.grin_amount - self.fee_amount
# Change output
self.change_child, self.change_entry = self.wallet.create_output(
self.change_amount)
self.change_entry.mark_locked()
self.change_output = self.wallet.entry_to_output(self.change_entry)
# Partial multisig output
self.partial_child, self.partial_entry = self.wallet.create_output(
self.grin_amount)
self.partial_entry.mark_locked()
self.partial_commit = self.wallet.commit_with_child_key(
0, self.partial_child)
# Offset
self.offset = BlindingFactor.from_secret_key(
SecretKey.random(self.secp))
# Refund output
refund_amount = self.grin_amount - self.refund_fee_amount
self.refund_child, self.refund_entry = self.wallet.create_output(
refund_amount)
self.refund_output = self.wallet.entry_to_output(self.refund_entry)
# Refund offset
self.refund_offset = BlindingFactor.from_secret_key(
SecretKey.random(self.secp))
# Nonces
self.nonce = SecretKey.random(self.secp)
self.public_nonce = self.nonce.to_public_key(self.secp)
self.refund_nonce = SecretKey.random(self.secp)
self.public_refund_nonce = self.refund_nonce.to_public_key(self.secp)
self.wallet.save()
def prepare_swap(self):
assert self.role == Role.BUYER and self.stage == Stage.LOCK, "Incorrect stage"
self.swap_nonce = SecretKey.random(self.secp)
self.public_swap_nonce = self.swap_nonce.to_public_key(self.secp)
self.swap_fee_amount = tx_fee(1, 1, MILLI_GRIN_UNIT)
self.swap_lock_height = self.lock_height + 1
self.swap_child, self.swap_entry = self.wallet.create_output(
self.grin_amount - self.swap_fee_amount)
self.wallet.save()
self.swap_offset = BlindingFactor.from_secret_key(
SecretKey.random(self.secp))
self.swap_output = self.wallet.entry_to_output(self.swap_entry)
self.fill_swap_signatures()
def send(node_url: str):
global secp, wallet, proof_builder
now = int(time())
send_amount = GRIN_UNIT
lock_height = 1
refund_lock_height = lock_height + 1440 # ~24 hours
dest_url = "http://127.0.0.1:18185"
fluff = True
secp = Secp256k1(None, FLAG_ALL)
wallet = Wallet.open(secp, "wallet_a")
print("Preparing to create multisig with {}".format(dest_url))
input_entries = wallet.select_outputs(send_amount +
tx_fee(1, 2, MILLI_GRIN_UNIT))
fee_amount = tx_fee(len(input_entries), 2, MILLI_GRIN_UNIT)
input_amount = sum(x.value for x in input_entries)
change_amount = input_amount - send_amount - fee_amount
refund_fee_amount = tx_fee(1, 1, MILLI_GRIN_UNIT)
print("Selected {} inputs".format(len(input_entries)))
tx = Transaction.empty(secp, 0, fee_amount, lock_height)
refund_tx = Transaction.empty(secp, 0, refund_fee_amount,
refund_lock_height)
blind_sum = BlindSum()
# Inputs
inputs = []
for entry in input_entries:
entry.mark_locked()
blind_sum.sub_child_key(wallet.derive_from_entry(entry))
input = wallet.entry_to_input(entry)
tx.add_input(secp, input)
inputs.append(input)
# Change output
change_child, change_entry = wallet.create_output(change_amount)
blind_sum.add_child_key(change_child)
change_output = wallet.entry_to_output(change_entry)
tx.add_output(secp, change_output)
# Multisig output
partial_child, partial_entry = wallet.create_output(send_amount)
partial_entry.mark_locked()
blind_sum.add_child_key(partial_child)
public_partial_commit = wallet.commit_with_child_key(0, partial_child)
# Refund output
refund_amount = send_amount - refund_fee_amount
refund_child, refund_entry = wallet.create_output(refund_amount)
refund_output = wallet.entry_to_output(refund_entry)
refund_tx.add_output(secp, refund_output)
# Offset
blind_sum.sub_blinding_factor(tx.offset)
# Excess
excess = wallet.chain.blind_sum(blind_sum).to_secret_key(secp)
public_excess = excess.to_public_key(secp)
# Nonce
nonce = SecretKey.random(secp)
public_nonce = nonce.to_public_key(secp)
# Refund nonce
refund_nonce = SecretKey.random(secp)
refund_public_nonce = refund_nonce.to_public_key(secp)
dct = {
"amount": send_amount,
"fee": fee_amount,
"refund_fee": refund_fee_amount,
"lock_height": lock_height,
"refund_lock_height": refund_lock_height,
"public_partial_commit": public_partial_commit.to_hex(secp).decode(),
"public_nonce": public_nonce.to_hex(secp).decode(),
"refund_public_nonce": refund_public_nonce.to_hex(secp).decode()
}
f = open("logs/{}_multisig_1.json".format(now), "w")
f.write(json.dumps(dct, indent=2))
f.close()
print("Sending to receiver..")
req = urlopen(dest_url, json.dumps(dct).encode(), 60)
dct2 = json.loads(req.read().decode())
f = open("logs/{}_multisig_2.json".format(now), "w")
f.write(json.dumps(dct2, indent=2))
f.close()
print("Received response, processing..")
public_partial_commit_recv = Commitment.from_hex(
secp, dct2['public_partial_commit'].encode())
public_partial_recv = public_partial_commit_recv.to_public_key(secp)
public_nonce_recv = PublicKey.from_hex(secp, dct2['public_nonce'].encode())
public_excess_recv = public_partial_commit_recv.to_public_key(secp)
partial_signature_recv = Signature.from_hex(
dct2['partial_signature'].encode())
refund_public_nonce_recv = PublicKey.from_hex(
secp, dct2['refund_public_nonce'].encode())
refund_public_excess_recv = PublicKey.from_hex(
secp, dct2['refund_public_excess'].encode())
refund_partial_signature_recv = Signature.from_hex(
dct2['refund_partial_signature'].encode())
# Commitment
commit = secp.commit_sum(
[public_partial_commit_recv,
wallet.commit(partial_entry)], [])
print("Total commit: {}".format(commit))
# Nonce sums
public_nonce_sum = PublicKey.from_combination(
secp, [public_nonce_recv, public_nonce])
refund_public_nonce_sum = PublicKey.from_combination(
secp, [refund_public_nonce_recv, refund_public_nonce])
# Step 2 of bulletproof
proof_builder = MultiPartyBulletProof(secp, partial_child,
public_partial_recv, send_amount,
commit)
t_1_recv = PublicKey.from_hex(secp, dct2['t_1'].encode())
t_2_recv = PublicKey.from_hex(secp, dct2['t_2'].encode())
t_1, t_2 = proof_builder.step_1()
proof_builder.fill_step_1(t_1_recv, t_2_recv)
tau_x = proof_builder.step_2()
dct3 = {
"t_1": t_1.to_hex(secp).decode(),
"t_2": t_2.to_hex(secp).decode(),
"tau_x": tau_x.to_hex().decode()
}
f = open("logs/{}_multisig_3.json".format(now), "w")
f.write(json.dumps(dct3, indent=2))
f.close()
print("Sending bulletproof component..")
req2 = urlopen(dest_url, json.dumps(dct3).encode(), 60)
dct4 = json.loads(req2.read().decode())
print("Received response")
f = open("logs/{}_multisig_4.json".format(now), "w")
f.write(json.dumps(dct4, indent=2))
f.close()
# Bulletproof
proof = RangeProof.from_bytearray(
bytearray(unhexlify(dct4['proof'].encode())))
output = Output(OutputFeatures.DEFAULT_OUTPUT, commit, proof)
assert output.verify(secp), "Invalid bulletproof"
tx.add_output(secp, output)
print("Created bulletproof")
# First we finalize the refund tx, and check its validity
refund_input = Input(OutputFeatures.DEFAULT_OUTPUT, commit)
refund_tx.add_input(secp, refund_input)
# Refund excess
refund_blind_sum = BlindSum()
refund_blind_sum.sub_child_key(partial_child)
refund_blind_sum.add_child_key(refund_child)
refund_blind_sum.sub_blinding_factor(refund_tx.offset)
refund_excess = wallet.chain.blind_sum(refund_blind_sum).to_secret_key(
secp)
refund_public_excess = refund_excess.to_public_key(secp)
# Refund partial signature
refund_partial_signature = aggsig.calculate_partial(
secp, refund_excess, refund_nonce, refund_public_nonce_sum,
refund_fee_amount, refund_lock_height)
# Refund final signature
refund_public_excess_sum = PublicKey.from_combination(
secp, [refund_public_excess_recv, refund_public_excess])
refund_signature = aggsig.add_partials(
secp, [refund_partial_signature_recv, refund_partial_signature],
refund_public_nonce_sum)
assert aggsig.verify(secp, refund_signature, refund_public_excess_sum, refund_fee_amount, refund_lock_height), \
"Unable to verify refund signature"
refund_kernel = refund_tx.kernels[0]
refund_kernel.excess = refund_tx.sum_commitments(secp)
refund_kernel.excess_signature = refund_signature
assert refund_tx.verify_kernels(secp), "Unable to verify refund kernel"
print("Refund tx is valid")
f = open("logs/{}_refund.json".format(now), "w")
f.write(json.dumps(refund_tx.to_dict(secp), indent=2))
f.close()
refund_tx_wrapper = {"tx_hex": refund_tx.to_hex(secp).decode()}
f = open("logs/{}_refund_hex.json".format(now), "w")
f.write(json.dumps(refund_tx_wrapper, indent=2))
f.close()
print("Finalizing multisig tx..")
# Partial signature
partial_signature = aggsig.calculate_partial(secp, excess, nonce,
public_nonce_sum, fee_amount,
lock_height)
# Final signature
public_excess_sum = PublicKey.from_combination(
secp, [public_excess_recv, public_excess])
signature = aggsig.add_partials(
secp, [partial_signature_recv, partial_signature], public_nonce_sum)
assert aggsig.verify(secp, signature, public_excess_sum, fee_amount,
lock_height), "Unable to verify signature"
kernel = tx.kernels[0]
kernel.excess = tx.sum_commitments(secp)
kernel.excess_signature = signature
assert tx.verify_kernels(secp), "Unable to verify kernel"
f = open("logs/{}_tx.json".format(now), "w")
f.write(json.dumps(tx.to_dict(secp), indent=2))
f.close()
tx_wrapper = {"tx_hex": tx.to_hex(secp).decode()}
f = open("logs/{}_tx_hex.json".format(now), "w")
f.write(json.dumps(tx_wrapper, indent=2))
f.close()
print("Submitting to node..")
urlopen("{}/v1/pool/push".format(node_url) + ("?fluff" if fluff else ""),
json.dumps(tx_wrapper).encode(), 600)
wallet.save()
print("Transaction complete!")
def send(node_url: str):
global secp, wallet
send_amount = 1
height = 33333
lock_height = 33333
features = 0
dest_url = "http://127.0.0.1:17175"
fluff = True
n_outputs = 2
secp = Secp256k1(None, FLAG_ALL)
wallet = Wallet.open(secp, "wallet_1")
print("Preparing to send {} grin to {}".format(send_amount / GRIN_UNIT, dest_url))
input_entries = wallet.select_outputs(send_amount + tx_fee(1, n_outputs, MILLI_GRIN_UNIT))
fee_amount = tx_fee(len(input_entries), n_outputs, MILLI_GRIN_UNIT)
input_amount = sum(x.value for x in input_entries)
change_amount = input_amount - send_amount - fee_amount
print("Selected {} inputs".format(len(input_entries)))
blind_sum = BlindSum()
slate = Slate.blank(secp, 2, send_amount, height, features, fee_amount, lock_height)
# Inputs
for entry in input_entries:
entry.mark_locked()
blind_sum.sub_child_key(wallet.derive_from_entry(entry))
slate.tx.add_input(secp, wallet.entry_to_input(entry))
# Change output
change_key, change_entry = wallet.create_output(change_amount)
blind_sum.add_child_key(change_key)
slate.tx.add_output(secp, wallet.entry_to_output(change_entry))
# Excess
blind_sum.sub_blinding_factor(slate.tx.offset)
excess = wallet.chain.blind_sum(blind_sum).to_secret_key(secp)
public_excess = excess.to_public_key(secp)
# Nonce
nonce = SecretKey.random(secp)
public_nonce = nonce.to_public_key(secp)
# Participant
participant = ParticipantData(0, public_excess, public_nonce, None)
slate.add_participant(participant)
print("Sending slate to receiver..")
req = urlopen(dest_url, json.dumps(slate.to_dict(secp)).encode(), 600)
slate = Slate.from_dict(secp, json.loads(req.read().decode()))
print("Received response, finishing transaction..")
participant = slate.get_participant(0)
slate.partial_signature(secp, participant, excess, nonce)
slate.finalize(secp)
tx_wrapper = {
"tx_hex": slate.tx.to_hex(secp).decode()
}
print("Submitting to node..")
urlopen("{}/v1/pool/push".format(node_url) + ("?fluff" if fluff else ""), json.dumps(tx_wrapper).encode(), 600)
wallet.save()
print("Transaction complete!")