def test_to_ascii(self, sk_ilp, vk_ilp):
sk = SigningKey(sk_ilp['b58'])
assert sk.to_ascii(encoding='base58') == sk_ilp['b58']
assert sk.to_ascii(encoding='base64') == sk_ilp['b64']
vk = VerifyingKey(vk_ilp['b58'])
assert vk.to_ascii(encoding='base58') == vk_ilp['b58']
assert vk.to_ascii(encoding='base64') == vk_ilp['b64']
class Ed25519Fulfillment(Fulfillment):
TYPE_ID = 4
FEATURE_BITMASK = 0x20
PUBKEY_LENGTH = 32
SIGNATURE_LENGTH = 64
FULFILLMENT_LENGTH = PUBKEY_LENGTH + SIGNATURE_LENGTH
def __init__(self, public_key=None):
"""
ED25519: Ed25519 signature condition.
This condition implements Ed25519 signatures.
ED25519 is assigned the type ID 4. It relies only on the ED25519 feature suite
which corresponds to a bitmask of 0x20.
Args:
public_key (VerifyingKey): Ed25519 publicKey
"""
if public_key and isinstance(public_key, (str, bytes)):
public_key = VerifyingKey(public_key)
if public_key and not isinstance(public_key, VerifyingKey):
raise TypeError
self.public_key = public_key
self.signature = None
def write_common_header(self, writer):
"""
Write static header fields.
Some fields are common between the hash and the fulfillment payload. This
method writes those field to anything implementing the Writer interface.
It is used internally when generating the hash of the condition, when
generating the fulfillment payload and when calculating the maximum fulfillment size.
Args:
writer (Writer, Hasher, Predictor): Target for outputting the header.
"""
writer.write_var_octet_string(self.public_key)
def sign(self, message, private_key):
"""
Sign the message.
This method will take the currently configured values for the message
prefix and suffix and create a signature using the provided Ed25519 private key.
Args:
message (string): message to be signed
private_key (string) Ed25519 private key
"""
sk = private_key
vk = VerifyingKey(base58.b58encode(sk.get_verifying_key().to_bytes()))
self.public_key = vk
# This would be the Ed25519ph version (JavaScript ES7):
# const message = crypto.createHash('sha512')
# .update(Buffer.concat([this.messagePrefix, this.message]))
# .digest()
self.signature = sk.sign(message, encoding=None)
def generate_hash(self):
"""
Generate the condition hash.
Since the public key is the same size as the hash we'd be putting out here,
we just return the public key.
"""
if not self.public_key:
raise ValueError('Requires a public publicKey')
return self.public_key.to_bytes()
def parse_payload(self, reader, *args):
"""
Parse the payload of an Ed25519 fulfillment.
Read a fulfillment payload from a Reader and populate this object with that fulfillment.
Args:
reader (Reader): Source to read the fulfillment payload from.
"""
self.public_key = VerifyingKey(base58.b58encode(reader.read_octet_string(Ed25519Fulfillment.PUBKEY_LENGTH)))
self.signature = reader.read_octet_string(Ed25519Fulfillment.SIGNATURE_LENGTH)
def write_payload(self, writer):
"""
Generate the fulfillment payload.
This writes the fulfillment payload to a Writer.
FULFILLMENT_PAYLOAD =
VARBYTES PUBLIC_KEY
VARBYTES SIGNATURE
Args:
writer (Writer): Subject for writing the fulfillment payload.
"""
writer.write_octet_string(self.public_key.to_bytes(), Ed25519Fulfillment.PUBKEY_LENGTH)
writer.write_octet_string(self.signature, Ed25519Fulfillment.SIGNATURE_LENGTH)
return writer
def calculate_max_fulfillment_length(self):
return Ed25519Fulfillment.FULFILLMENT_LENGTH
def serialize_json(self):
"""
Generate a JSON object of the fulfillment
Returns:
"""
return json.dumps(
{
'type': 'fulfillment',
'type_id': Ed25519Fulfillment.TYPE_ID,
'bitmask': self.bitmask,
'public_key': self.public_key.to_ascii(encoding='base58').decode(),
'signature': base58.b58encode(self.signature) if self.signature else None
}
)
def parse_json(self, json_data):
"""
Generate fulfillment payload from a json
Args:
json_data: json description of the fulfillment
Returns:
Fulfillment
"""
self.public_key = VerifyingKey(json_data['public_key'])
self.signature = base58.b58decode(json_data['signature']) if json_data['signature'] else None
def validate(self, message=None):
"""
Verify the signature of this Ed25519 fulfillment.
The signature of this Ed25519 fulfillment is verified against the provided message and public key.
Args:
message (str): Message to validate against.
Return:
boolean: Whether this fulfillment is valid.
"""
if not (message and self.signature):
return False
return self.public_key.verify(message, self.signature, encoding=None)
def test_verifying_key_init(self, vk_ilp):
vk = VerifyingKey(vk_ilp['b58'])
assert vk.to_ascii(encoding='base64') == vk_ilp['b64']
assert vk.to_bytes() == vk_ilp['byt']