def build_transactions(self):
assert self.role == Role.SELLER and self.stage == Stage.LOCK, "Incorrect stage"
# Check output range proof
output = Output(OutputFeatures.DEFAULT_OUTPUT, self.commit,
self.range_proof)
assert output.verify(self.secp), "Invalid bulletproof"
# Build refund tx
refund_input = Input(OutputFeatures.DEFAULT_OUTPUT, self.commit)
public_refund_nonce_sum = PublicKey.from_combination(
self.secp,
[self.public_refund_nonce, self.foreign_public_refund_nonce])
refund_signature = aggsig.add_partials(self.secp, [
self.partial_refund_signature,
self.foreign_partial_refund_signature
], public_refund_nonce_sum)
assert aggsig.verify(
self.secp, refund_signature, self.public_refund_excess,
self.refund_fee_amount,
self.refund_lock_height), "Unable to verify refund signature"
refund_kernel = Kernel(0, self.refund_fee_amount,
self.refund_lock_height, None, None)
self.refund_tx = Transaction([refund_input], [self.refund_output],
[refund_kernel], self.refund_offset)
refund_kernel.excess = self.refund_tx.sum_commitments(self.secp)
refund_kernel.excess_signature = refund_signature
assert self.refund_tx.verify_kernels(
self.secp), "Unable to verify refund kernel"
# Build multisig tx
public_nonce_sum = PublicKey.from_combination(
self.secp, [self.public_nonce, self.foreign_public_nonce])
signature = aggsig.add_partials(
self.secp,
[self.partial_signature, self.foreign_partial_signature],
public_nonce_sum)
assert aggsig.verify(self.secp, signature, self.public_excess, self.fee_amount, self.lock_height), \
"Unable to verify signature"
kernel = Kernel(0, self.fee_amount, self.lock_height, None, None)
self.tx = Transaction(self.inputs, [self.change_output, output],
[kernel], self.offset)
kernel.excess = self.tx.sum_commitments(self.secp)
kernel.excess_signature = signature
assert self.tx.verify_kernels(self.secp), "Unable to verify kernel"
self.swap_nonce = SecretKey.random(self.secp)
self.public_swap_nonce = self.swap_nonce.to_public_key(self.secp)
def test_sig():
# Test Grin-like signature scheme
secp = Secp256k1(None, FLAG_ALL)
nonce_a = SecretKey.random(secp)
public_nonce_a = nonce_a.to_public_key(secp)
nonce_b = SecretKey.random(secp)
public_nonce_b = nonce_b.to_public_key(secp)
public_nonce_sum = PublicKey.from_combination(
secp, [public_nonce_a, public_nonce_b])
excess_a = SecretKey.random(secp)
public_excess_a = excess_a.to_public_key(secp)
excess_b = SecretKey.random(secp)
public_excess_b = excess_b.to_public_key(secp)
public_excess_sum = PublicKey.from_combination(
secp, [public_excess_a, public_excess_b])
fee = randint(1, 999999)
lock_height = randint(1, 999999)
# Partial signature for A
sig_a = aggsig.calculate_partial(secp, excess_a, nonce_a,
public_excess_sum, public_nonce_sum, fee,
lock_height)
assert aggsig.verify_partial(secp, sig_a, public_excess_a,
public_excess_sum, public_nonce_sum, fee,
lock_height)
# Partial signature for B
sig_b = aggsig.calculate_partial(secp, excess_b, nonce_b,
public_excess_sum, public_nonce_sum, fee,
lock_height)
assert aggsig.verify_partial(secp, sig_b, public_excess_b,
public_excess_sum, public_nonce_sum, fee,
lock_height)
# Total signature
sig = aggsig.add_partials(secp, [sig_a, sig_b], public_nonce_sum)
assert aggsig.verify(secp, sig, public_excess_sum, fee, lock_height)
rnd_sig = Signature(bytearray(urandom(64)))
assert not aggsig.verify(secp, rnd_sig, public_excess_sum, fee,
lock_height)
public_rnd = SecretKey.random(secp).to_public_key(secp)
assert not aggsig.verify(secp, sig, public_rnd, fee, lock_height)
assert not aggsig.verify(secp, sig, public_excess_sum, 0, lock_height)
assert not aggsig.verify(secp, sig, public_excess_sum, fee, 0)
def fill_swap_signatures(self):
buyer = self.role == Role.BUYER
assert (buyer and self.stage == Stage.LOCK) or (
not buyer and self.stage == Stage.SWAP), "Incorrect stage"
# Public (total) swap excess
pos = [
self.swap_output.commit,
self.secp.commit_value(self.swap_fee_amount)
]
neg = [self.commit, self.secp.commit(0, self.swap_offset)]
self.public_swap_excess = self.secp.commit_sum(pos, neg).to_public_key(
self.secp)
# Partial swap excess
swap_blind_sum = BlindSum()
swap_blind_sum.sub_child_key(self.partial_child)
if buyer:
swap_blind_sum.add_child_key(self.swap_child)
swap_blind_sum.sub_blinding_factor(self.swap_offset)
swap_excess = self.wallet.chain.blind_sum(
swap_blind_sum).to_secret_key(self.secp)
# Nonce sum
public_swap_nonce_sum = PublicKey.from_combination(
self.secp,
[self.public_swap_nonce, self.foreign_public_swap_nonce])
if not buyer:
# Verify that partial signature is valid with swap secret
pos = [self.swap_output.commit]
neg = [
self.foreign_partial_commit,
self.secp.commit(0, self.swap_offset),
self.secp.commit_value(self.grin_amount - self.swap_fee_amount)
]
foreign_public_partial_swap_excess = self.secp.commit_sum(
pos, neg).to_public_key(self.secp)
assert aggsig.verify_partial_adaptor(
self.secp, self.foreign_partial_swap_adaptor,
foreign_public_partial_swap_excess, self.public_lock,
self.public_swap_excess, public_swap_nonce_sum,
self.swap_fee_amount,
self.swap_lock_height), "Partial swap signature not valid"
# Partial swap signature
self.partial_swap_signature = aggsig.calculate_partial(
self.secp, swap_excess, self.swap_nonce, self.public_swap_excess,
public_swap_nonce_sum, self.swap_fee_amount, self.swap_lock_height)
if buyer:
self.partial_swap_adaptor = aggsig.calculate_partial_adaptor(
self.secp, swap_excess, self.swap_nonce, self.secret_lock,
self.public_swap_excess, public_swap_nonce_sum,
self.swap_fee_amount, self.swap_lock_height)
def finalize_swap(self):
seller = self.role == Role.SELLER
assert (seller and self.stage == Stage.DONE) or (
not seller and self.stage == Stage.SWAP), "Incorrect stage"
if seller:
self.secret_lock = self.foreign_partial_swap_adaptor.scalar(
self.secp).add(
self.secp,
self.foreign_partial_swap_signature.scalar(
self.secp).negate(self.secp))
public_lock = self.secret_lock.to_public_key(self.secp)
assert self.public_lock == public_lock, "Invalid secret lock, this should never happen"
if self.is_ether_swap():
self.claim = self.secp.sign_recoverable(
self.secret_lock, bytearray([0] * 32))
else:
swap_input = Input(OutputFeatures.DEFAULT_OUTPUT, self.commit)
public_swap_nonce_sum = PublicKey.from_combination(
self.secp,
[self.public_swap_nonce, self.foreign_public_swap_nonce])
swap_signature = aggsig.add_partials(self.secp, [
self.partial_swap_signature,
self.foreign_partial_swap_signature
], public_swap_nonce_sum)
assert aggsig.verify(
self.secp, swap_signature, self.public_swap_excess,
self.swap_fee_amount,
self.swap_lock_height), "Unable to verify swap signature"
swap_kernel = Kernel(0, self.swap_fee_amount,
self.swap_lock_height, None, None)
self.swap_tx = Transaction([swap_input], [self.swap_output],
[swap_kernel], self.swap_offset)
swap_kernel.excess = self.swap_tx.sum_commitments(self.secp)
swap_kernel.excess_signature = swap_signature
assert self.swap_tx.verify_kernels(
self.secp), "Unable to verify swap kernel"
def post(handler: HTTPServerHandler):
global secp, wallet, server, proof_builder
if secp is None:
secp = Secp256k1(None, FLAG_ALL)
wallet = Wallet.open(secp, "wallet_b")
try:
length = handler.headers['Content-Length']
length = 0 if length is None else int(length)
if length == 0:
raise Exception("Invalid length")
dct = json.loads(handler.rfile.read(length).decode())
if proof_builder is not None:
print("Creating bulletproof components")
t_1_sender = PublicKey.from_hex(secp, dct['t_1'].encode())
t_2_sender = PublicKey.from_hex(secp, dct['t_2'].encode())
proof_builder.fill_step_1(t_1_sender, t_2_sender)
tau_x_sender = SecretKey.from_hex(secp, dct['tau_x'].encode())
proof_builder.fill_step_2(tau_x_sender)
proof = proof_builder.finalize()
wallet.save()
dct2 = {"proof": hexlify(bytes(proof.proof)).decode()}
handler.json_response((json.dumps(dct2) + "\r\n").encode())
print("Sent response")
return
send_amount = dct['amount']
fee_amount = dct['fee']
refund_fee_amount = dct['refund_fee']
lock_height = dct['lock_height']
refund_lock_height = dct['refund_lock_height']
print("Receive {} grin in multisig".format(send_amount / GRIN_UNIT))
public_partial_commit_sender = Commitment.from_hex(
secp, dct['public_partial_commit'].encode())
public_partial_sender = public_partial_commit_sender.to_public_key(
secp)
public_nonce_sender = PublicKey.from_hex(secp,
dct['public_nonce'].encode())
refund_public_nonce_sender = PublicKey.from_hex(
secp, dct['refund_public_nonce'].encode())
# Multisig output
partial_child, partial_entry = wallet.create_output(send_amount)
partial_entry.mark_locked()
public_partial_commit = wallet.commit_with_child_key(0, partial_child)
# Commitment
commit = secp.commit_sum(
[public_partial_commit_sender,
wallet.commit(partial_entry)], [])
print("Total commit: {}".format(commit))
# Nonce
nonce = SecretKey.random(secp)
public_nonce = nonce.to_public_key(secp)
public_nonce_sum = PublicKey.from_combination(
secp, [public_nonce_sender, public_nonce])
# Refund excess
refund_blind_sum = BlindSum()
refund_blind_sum.sub_child_key(partial_child)
refund_excess = wallet.chain.blind_sum(refund_blind_sum).to_secret_key(
secp)
refund_public_excess = refund_excess.to_public_key(secp)
# Refund nonce
refund_nonce = SecretKey.random(secp)
refund_public_nonce = refund_nonce.to_public_key(secp)
refund_public_nonce_sum = PublicKey.from_combination(
secp, [refund_public_nonce_sender, refund_public_nonce])
# Start building the bulletproof for the multisig output
proof_builder = MultiPartyBulletProof(secp, partial_child,
public_partial_sender,
send_amount, commit)
t_1, t_2 = proof_builder.step_1()
# Partial signature
partial_signature = aggsig.calculate_partial(secp, partial_child.key,
nonce, public_nonce_sum,
fee_amount, lock_height)
# Refund partial signature
refund_partial_signature = aggsig.calculate_partial(
secp, refund_excess, refund_nonce, refund_public_nonce_sum,
refund_fee_amount, refund_lock_height)
dct2 = {
"public_partial_commit":
public_partial_commit.to_hex(secp).decode(),
"refund_public_excess": refund_public_excess.to_hex(secp).decode(),
"public_nonce": public_nonce.to_hex(secp).decode(),
"refund_public_nonce": refund_public_nonce.to_hex(secp).decode(),
"partial_signature": partial_signature.to_hex().decode(),
"refund_partial_signature":
refund_partial_signature.to_hex().decode(),
"t_1": t_1.to_hex(secp).decode(),
"t_2": t_2.to_hex(secp).decode()
}
handler.json_response((json.dumps(dct2) + "\r\n").encode())
print("Sent response")
except Exception as e:
print("Unable to parse input: {}".format(e))
handler.error_response()
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 public_nonce_sum(self, secp: Secp256k1) -> PublicKey:
return PublicKey.from_combination(
secp, [x.public_nonce for x in self.participant_data])
def finalize_swap(self):
seller = self.role == Role.SELLER
assert (seller and self.stage == Stage.DONE) or (
not seller and self.stage == Stage.SWAP), "Incorrect stage"
if seller:
self.secret_lock = self.foreign_partial_swap_adaptor.scalar(
self.secp).add(
self.secp,
self.foreign_partial_swap_signature.scalar(
self.secp).negate(self.secp))
public_lock = self.secret_lock.to_public_key(self.secp)
assert self.public_lock == public_lock, "Invalid secret lock, this should never happen"
if self.is_bitcoin_swap():
tx = BitcoinTransaction(2, [], [], int(time()))
input_script = self.generate_btc_script()
for output_point in self.btc_output_points:
tx.add_input(
BitcoinInput(output_point.txid, output_point.index,
input_script, bytearray(), None))
output = BitcoinOutput(
1,
Script.p2(
Address.from_base58check(
self.swap_receive_address.encode())))
tx.add_output(output)
tx_size = len(tx.to_bytearray()) + 270 * len(
self.btc_output_points) # estimate total tx size
fee = 2 * tx_size # 2 sat/B
output.value = self.swap_amount - fee
for i in range(len(tx.inputs)):
signature_a = tx.raw_signature(self.secp, i,
self.swap_cosign)
signature_b = tx.raw_signature(self.secp, i,
self.secret_lock)
prev_script = self.generate_btc_script()
script_sig = bytearray()
script_sig.append(OP_FALSE)
script_sig.extend(script_write_bytes(len(signature_a)))
script_sig.extend(signature_a)
script_sig.extend(script_write_bytes(len(signature_b)))
script_sig.extend(signature_b)
script_sig.append(OP_FALSE)
script_sig.extend(script_write_bytes(len(prev_script)))
script_sig.extend(prev_script)
tx.inputs[i].script_sig = script_sig
self.claim = hexlify(tx.to_bytearray())
if self.is_ether_swap():
self.claim = self.secp.sign_recoverable(
self.secret_lock, bytearray([0] * 32))
else:
swap_input = Input(OutputFeatures.DEFAULT_OUTPUT, self.commit)
public_swap_nonce_sum = PublicKey.from_combination(
self.secp,
[self.public_swap_nonce, self.foreign_public_swap_nonce])
swap_signature = aggsig.add_partials(self.secp, [
self.partial_swap_signature,
self.foreign_partial_swap_signature
], public_swap_nonce_sum)
assert aggsig.verify(
self.secp, swap_signature, self.public_swap_excess,
self.swap_fee_amount,
self.swap_lock_height), "Unable to verify swap signature"
swap_kernel = Kernel(0, self.swap_fee_amount,
self.swap_lock_height, None, None)
self.swap_tx = Transaction([swap_input], [self.swap_output],
[swap_kernel], self.swap_offset)
swap_kernel.excess = self.swap_tx.sum_commitments(self.secp)
swap_kernel.excess_signature = swap_signature
assert self.swap_tx.verify_kernels(
self.secp), "Unable to verify swap kernel"
def fill_signatures(self):
seller = self.role == Role.SELLER
assert (not seller and self.stage == Stage.INIT) or (
seller and self.stage == Stage.SIGN), "Incorrect stage"
# Public (total) excess
pos = [
self.commit, self.change_output.commit,
self.secp.commit_value(self.fee_amount)
]
neg = [x.commit for x in self.inputs]
neg.append(self.secp.commit(0, self.offset))
self.public_excess = self.secp.commit_sum(pos,
neg).to_public_key(self.secp)
# Partial excess
blind_sum = BlindSum()
blind_sum.add_child_key(self.partial_child)
if seller:
blind_sum.add_child_key(self.change_child)
for entry in self.input_entries:
blind_sum.sub_child_key(self.wallet.derive_from_entry(entry))
blind_sum.sub_blinding_factor(self.offset)
excess = self.wallet.chain.blind_sum(blind_sum).to_secret_key(
self.secp)
# Partial signature
public_nonce_sum = PublicKey.from_combination(
self.secp, [self.public_nonce, self.foreign_public_nonce])
self.partial_signature = aggsig.calculate_partial(
self.secp, excess, self.nonce, self.public_excess,
public_nonce_sum, self.fee_amount, self.lock_height)
# First step of multi party bullet proof
proof_builder = TwoPartyBulletProof(
self.secp, self.partial_child.key,
self.foreign_partial_commit.to_public_key(self.secp),
self.grin_amount, self.commit)
self.t_1, self.t_2 = proof_builder.round_1()
if seller:
proof_builder.fill_round_1(self.foreign_t_1, self.foreign_t_2)
self.tau_x = proof_builder.round_2()
# Public (total) refund excess
pos = [
self.refund_output.commit,
self.secp.commit_value(self.refund_fee_amount)
]
neg = [self.commit, self.secp.commit(0, self.refund_offset)]
self.public_refund_excess = self.secp.commit_sum(
pos, neg).to_public_key(self.secp)
# Partial refund excess
refund_blind_sum = BlindSum()
refund_blind_sum.sub_child_key(self.partial_child)
if seller:
refund_blind_sum.add_child_key(self.refund_child)
refund_blind_sum.sub_blinding_factor(self.refund_offset)
refund_excess = self.wallet.chain.blind_sum(
refund_blind_sum).to_secret_key(self.secp)
# Partial refund signature
public_refund_nonce_sum = PublicKey.from_combination(
self.secp,
[self.public_refund_nonce, self.foreign_public_refund_nonce])
self.partial_refund_signature = aggsig.calculate_partial(
self.secp, refund_excess, self.refund_nonce,
self.public_refund_excess, public_refund_nonce_sum,
self.refund_fee_amount, self.refund_lock_height)
def test_public_key():
secp = Secp256k1(None, FLAG_ALL)
# (de)serialization
secret_key = SecretKey.random(secp)
public_key = secret_key.to_public_key(secp)
public_key_2 = PublicKey.from_bytearray(secp,
public_key.to_bytearray(secp))
assert public_key == public_key_2
# (a+b)*G = a*G + b*G
secret_key_a = SecretKey.random(secp)
secret_key_b = SecretKey.random(secp)
secret_key_a_b = secret_key_a.add(secp, secret_key_b)
public_key_a = secret_key_a.to_public_key(secp)
public_key_b = secret_key_b.to_public_key(secp)
public_key_a_b = secret_key_a_b.to_public_key(secp)
public_key_a_b_2 = PublicKey.from_combination(secp,
[public_key_a, public_key_b])
public_key_a_b_3 = public_key_a.add_scalar(secp, secret_key_b)
assert public_key_a_b == public_key_a_b_2
assert public_key_a_b == public_key_a_b_3
# (ab)*G = a(b*G) = b(a*G)
secret_key_a = SecretKey.random(secp)
secret_key_b = SecretKey.random(secp)
secret_key_ab = secret_key_a.mul(secp, secret_key_b)
public_key_ab = secret_key_ab.to_public_key(secp)
public_key_ab_2 = secret_key_a.to_public_key(secp)
public_key_ab_2.mul_assign(secp, secret_key_b)
public_key_ab_3 = secret_key_b.to_public_key(secp)
public_key_ab_3.mul_assign(secp, secret_key_a)
assert public_key_ab == public_key_ab_2
assert public_key_ab == public_key_ab_3
# (c(a+b))*G = c(a*G) + c(b*G)
secret_key_a = SecretKey.random(secp)
secret_key_b = SecretKey.random(secp)
secret_key_c = SecretKey.random(secp)
secret_key_ca_b = secret_key_a.add(secp, secret_key_b)
secret_key_ca_b.mul_assign(secp, secret_key_c)
public_key_ca_b = secret_key_ca_b.to_public_key(secp)
public_key_ca = secret_key_a.to_public_key(secp)
public_key_ca.mul_assign(secp, secret_key_c)
public_key_cb = secret_key_b.to_public_key(secp)
public_key_cb.mul_assign(secp, secret_key_c)
public_key_ca_cb = public_key_ca.add(secp, public_key_cb)
assert public_key_ca_b == public_key_ca_cb
# (a+b+c)*G = a*G + b*G + c*G
secret_key_a = SecretKey.random(secp)
secret_key_b = SecretKey.random(secp)
secret_key_c = SecretKey.random(secp)
secret_key_a_b_c = secret_key_a.add(secp, secret_key_b)
secret_key_a_b_c.add_assign(secp, secret_key_c)
public_key_a_b_c = secret_key_a_b_c.to_public_key(secp)
public_key_a = secret_key_a.to_public_key(secp)
public_key_b = secret_key_b.to_public_key(secp)
public_key_c = secret_key_c.to_public_key(secp)
public_key_a_b_c_2 = PublicKey.from_combination(
secp, [public_key_a, public_key_b, public_key_c])
assert public_key_a_b_c == public_key_a_b_c_2