py-libp2p/libp2p/peer/id.py
Jonathan de Jong 794d2101e9 fixes #197
2019-12-17 11:00:45 +01:00

96 lines
2.5 KiB
Python

import hashlib
from typing import Union
import base58
import multihash
from libp2p.crypto.keys import PublicKey
# NOTE: On inlining...
# See: https://github.com/libp2p/specs/issues/138
# NOTE: enabling to be interoperable w/ the Go implementation
ENABLE_INLINING = True
MAX_INLINE_KEY_LENGTH = 42
IDENTITY_MULTIHASH_CODE = 0x00
if ENABLE_INLINING:
class IdentityHash:
_digest: bytes
def __init__(self) -> None:
self._digest = bytearray()
def update(self, input: bytes) -> None:
self._digest += input
def digest(self) -> bytes:
return self._digest
multihash.FuncReg.register(
IDENTITY_MULTIHASH_CODE, "identity", hash_new=lambda: IdentityHash()
)
class ID:
_bytes: bytes
_xor_id: int = None
_b58_str: str = None
def __init__(self, peer_id_bytes: bytes) -> None:
self._bytes = peer_id_bytes
@property
def xor_id(self) -> int:
if not self._xor_id:
self._xor_id = int(sha256_digest(self._bytes).hex(), 16)
return self._xor_id
def to_bytes(self) -> bytes:
return self._bytes
def to_base58(self) -> str:
if not self._b58_str:
self._b58_str = base58.b58encode(self._bytes).decode()
return self._b58_str
def __repr__(self) -> str:
return f"<libp2p.peer.id.ID ({self.to_string()})>"
__str__ = pretty = to_string = to_base58
def __eq__(self, other: object) -> bool:
if isinstance(other, str):
return self.to_base58() == other
elif isinstance(other, bytes):
return self._bytes == other
elif isinstance(other, ID):
return self._bytes == other._bytes
else:
return NotImplemented
def __hash__(self) -> int:
return hash(self._bytes)
@classmethod
def from_base58(cls, b58_encoded_peer_id_str: str) -> "ID":
peer_id_bytes = base58.b58decode(b58_encoded_peer_id_str)
pid = ID(peer_id_bytes)
return pid
@classmethod
def from_pubkey(cls, key: PublicKey) -> "ID":
serialized_key = key.serialize()
algo = multihash.Func.sha2_256
if ENABLE_INLINING and len(serialized_key) <= MAX_INLINE_KEY_LENGTH:
algo = IDENTITY_MULTIHASH_CODE
mh_digest = multihash.digest(serialized_key, algo)
return cls(mh_digest.encode())
def sha256_digest(data: Union[str, bytes]) -> bytes:
if isinstance(data, str):
data = data.encode("utf8")
return hashlib.sha256(data).digest()