nucypher.policy

Submodules

class Card(character_flag: Union[ALICE(b’?\xba\x93\xd8V\xb4G\x95’), BOB(b’\xfd(1@\x11\x98k\xd4’)], verifying_key: Union[umbral.PublicKey, bytes], encrypting_key: Union[umbral.PublicKey, bytes, None] = None, nickname: Union[bytes, str, None] = None)

Bases: object

” A simple serializable representation of a character’s public materials.

TRUNCATE = 16

CARD_DIR = PosixPath('/home/docs/.local/share/nucypher/cards')

exception InvalidCard

Bases: Exception

Raised when an invalid, corrupted, or otherwise unsable card is encountered

exception UnknownCard

Bases: Exception

Raised when a card cannot be found in storage

exception UnsignedCard

Bases: Exception

Raised when a card serialization cannot be handled due to the lack of a signature

property character

classmethod from_bytes(card_bytes: bytes) → nucypher.policy.identity.Card

classmethod from_hex(hexdata: str)

to_hex() → str

classmethod from_base64(b64data: str)

to_base64() → str

to_qr_code()

classmethod from_dict(card: Dict)

to_dict() → Dict

describe(truncate: int = 16) → Dict

to_json(as_string: bool = True) → Union[dict, str]

classmethod from_character(character: nucypher.characters.base.Character, nickname: Optional[str] = None) → nucypher.policy.identity.Card

property verifying_key

property encrypting_key

property id

set_nickname(nickname: str) → None

property nickname

property filepath

property is_saved

save(encoder: Callable = <function b64encode>, overwrite: bool = False) → pathlib.Path

classmethod lookup(identifier: str, card_dir: Optional[pathlib.Path] = PosixPath('/home/docs/.local/share/nucypher/cards')) → pathlib.Path

Resolve a card ID or nickname into a Path object

classmethod load(filepath: Optional[pathlib.Path] = None, identifier: str = None, card_dir: Optional[pathlib.Path] = None, decoder: Callable = <function b64decode>) → nucypher.policy.identity.Card

delete() → None

class PolicyMessageKit(policy_encrypting_key: umbral.PublicKey, threshold: int, result: nucypher.policy.kits.RetrievalResult, message_kit: nucypher_core.MessageKit)

Bases: object

classmethod from_message_kit(message_kit: nucypher_core.MessageKit, policy_encrypting_key: umbral.PublicKey, threshold: int) → nucypher.policy.kits.PolicyMessageKit

as_retrieval_kit() → nucypher_core.RetrievalKit

decrypt(sk: umbral.SecretKey) → bytes

is_decryptable_by_receiver() → bool

with_result(result: nucypher.policy.kits.RetrievalResult) → nucypher.policy.kits.PolicyMessageKit

class RetrievalResult(cfrags: Dict[NewType.<locals>.new_type, umbral.VerifiedCapsuleFrag])

Bases: object

An object representing retrieval results for a single capsule.

classmethod empty()

canonical_addresses() → Set[bytes]

with_result(result: nucypher.policy.kits.RetrievalResult) → nucypher.policy.kits.RetrievalResult

Joins two RetrievalResult objects.

If both objects contain cfrags from the same Ursula, the one from result will be kept.

class Policy(publisher: Alice, label: bytes, expiration: maya.core.MayaDT, bob: Bob, kfrags: Sequence[umbral.VerifiedKeyFrag], public_key: umbral.PublicKey, threshold: int)

Bases: abc.ABC

An edict by Alice, arranged with n Ursulas, to perform re-encryption for a specific Bob.

log

Drop-in replacement of Twisted’s Logger, patching the emit() method to tolerate inputs with curly braces, i.e., not compliant with PEP 3101.

See Issue #724 and, particularly, https://github.com/nucypher/nucypher/issues/724#issuecomment-600190455

exception PolicyException

Bases: Exception

Base exception for policy exceptions

exception NotEnoughUrsulas

Bases: nucypher.policy.policies.Policy.PolicyException

Raised when a Policy cannot be generated due an an insufficient number of available qualified network nodes.

exception EnactmentError

Bases: nucypher.policy.policies.Policy.PolicyException

Raised if one or more Ursulas failed to enact the policy.

exception Unpaid

Bases: nucypher.policy.policies.Policy.PolicyException

Raised when a worker expects policy payment but receives none.

exception Unknown

Bases: nucypher.policy.policies.Policy.PolicyException

Raised when a worker cannot find a published policy for a given policy ID

exception Inactive

Bases: nucypher.policy.policies.Policy.PolicyException

Raised when a worker is requested to perform re-encryption for a disabled policy

exception Expired

Bases: nucypher.policy.policies.Policy.PolicyException

Raised when a worker is requested to perform re-encryption for an expired policy

exception Unauthorized

Bases: nucypher.policy.policies.Policy.PolicyException

Raised when Bob is not authorized to request re-encryption from Ursula..

exception Revoked

Bases: nucypher.policy.policies.Policy.Unauthorized

Raised when a policy is revoked has been revoked access

enact(network_middleware: nucypher.network.middleware.RestMiddleware, ursulas: Optional[Iterable[Ursula]] = None) → EnactedPolicy

Attempts to enact the policy, returns an EnactedPolicy object on success.

class FederatedPolicy(publisher: Alice, label: bytes, expiration: maya.core.MayaDT, bob: Bob, kfrags: Sequence[umbral.VerifiedKeyFrag], public_key: umbral.PublicKey, threshold: int)

Bases: nucypher.policy.policies.Policy

class BlockchainPolicy(value: int, rate: int, payment_periods: int, *args, **kwargs)

Bases: nucypher.policy.policies.Policy

exception InvalidPolicyValue

Bases: ValueError

static generate_policy_parameters(shares: int, payment_periods: int, value: int = None, rate: int = None) → dict

class EnactedPolicy(hrac: nucypher_core.HRAC, label: bytes, public_key: umbral.PublicKey, threshold: int, treasure_map: EncryptedTreasureMap, revocation_kit: nucypher.policy.revocation.RevocationKit, publisher_verifying_key: umbral.PublicKey)

Bases: object

make_federated_staker_reservoir(known_nodes: nucypher.acumen.perception.FleetSensor, exclude_addresses: Optional[Iterable[NewType.<locals>.new_type]] = None, include_addresses: Optional[Iterable[NewType.<locals>.new_type]] = None)

Get a sampler object containing the federated stakers.

make_decentralized_staker_reservoir(staking_agent: nucypher.blockchain.eth.agents.StakingEscrowAgent, duration_periods: int, exclude_addresses: Optional[Iterable[NewType.<locals>.new_type]] = None, include_addresses: Optional[Iterable[NewType.<locals>.new_type]] = None, pagination_size: int = None)

Get a sampler object containing the currently registered stakers.

class MergedReservoir(values: Iterable, reservoir: nucypher.blockchain.eth.agents.StakersReservoir)

Bases: object

A reservoir made of a list of addresses and a StakersReservoir. Draws the values from the list first, then from StakersReservoir, then returns None on subsequent calls.

class PrefetchStrategy(reservoir: nucypher.policy.reservoir.MergedReservoir, need_successes: int)

Bases: object

Encapsulates the batch draw strategy from a reservoir. Determines how many values to draw based on the number of values that have already led to successes.

class RevocationKit(treasure_map, signer: nucypher.crypto.signing.SignatureStamp)

Bases: object

property revokable_addresses

Returns a Set of revokable addresses in the checksum address formatting

add_confirmation(ursula_address, signed_receipt)

Adds a signed confirmation of Ursula’s ability to revoke the node.