def fulfill_threshold_signature_fulfillment(fulfillment, parsed_fulfillment, fulfillment_message, key_pairs):
"""Fulfill a cryptoconditions.ThresholdSha256Fulfillment
Args:
fulfillment (dict): BigchainDB fulfillment to fulfill.
parsed_fulfillment (cryptoconditions.ThresholdSha256Fulfillment): cryptoconditions.ThresholdSha256Fulfillment instance.
fulfillment_message (dict): message to sign.
key_pairs (dict): dictionary of (public_key, private_key) pairs.
Returns:
object: fulfilled cryptoconditions.ThresholdSha256Fulfillment
"""
parsed_fulfillment_copy = copy.deepcopy(parsed_fulfillment)
parsed_fulfillment.subconditions = []
for current_owner in fulfillment['current_owners']:
try:
subfulfillment = parsed_fulfillment_copy.get_subcondition_from_vk(current_owner)[0]
except IndexError:
exceptions.KeypairMismatchException('Public key {} cannot be found in the fulfillment'
.format(current_owner))
try:
subfulfillment.sign(serialize(fulfillment_message), key_pairs[current_owner])
except KeyError:
raise exceptions.KeypairMismatchException('Public key {} is not a pair to any of the private keys'
.format(current_owner))
parsed_fulfillment.add_subfulfillment(subfulfillment)
return parsed_fulfillment
def fulfill_simple_signature_fulfillment(fulfillment, parsed_fulfillment,
fulfillment_message, key_pairs):
"""Fulfill a cryptoconditions.Ed25519Fulfillment
Args:
fulfillment (dict): BigchainDB fulfillment to fulfill.
parsed_fulfillment (cryptoconditions.Ed25519Fulfillment): cryptoconditions.Ed25519Fulfillment instance.
fulfillment_message (dict): message to sign.
key_pairs (dict): dictionary of (public_key, private_key) pairs.
Returns:
object: fulfilled cryptoconditions.Ed25519Fulfillment
"""
current_owner = fulfillment['current_owners'][0]
try:
parsed_fulfillment.sign(serialize(fulfillment_message),
key_pairs[current_owner])
except KeyError:
raise exceptions.KeypairMismatchException(
'Public key {} is not a pair to any of the private keys'.format(
current_owner))
return parsed_fulfillment