def from_string(cls, hash):
# NOTE: assuming hash will be unicode, or use ascii-compatible encoding.
# TODO: switch to working w/ str or unicode
if isinstance(hash, unicode):
hash = hash.encode("utf-8")
if not isinstance(hash, bytes):
raise exc.ExpectedStringError(hash, "hash")
m = cls._hash_regex.match(hash)
if not m:
raise exc.MalformedHashError(cls)
type, version, memory_cost, time_cost, parallelism, keyid, data, salt, digest = \
m.group("type", "version", "memory_cost", "time_cost", "parallelism",
"keyid", "data", "salt", "digest")
if keyid:
raise NotImplementedError("argon2 'keyid' parameter not supported")
return cls(
type=type.decode("ascii"),
version=int(version) if version else 0x10,
memory_cost=int(memory_cost),
rounds=int(time_cost),
parallelism=int(parallelism),
salt=b64s_decode(salt) if salt else None,
data=b64s_decode(data) if data else None,
checksum=b64s_decode(digest) if digest else None,
)
def __init__(self, charmap, big=False):
# validate charmap, generate encode64/decode64 helper functions.
if isinstance(charmap, unicode):
charmap = charmap.encode("latin-1")
elif not isinstance(charmap, bytes):
raise exc.ExpectedStringError(charmap, "charmap")
if len(charmap) != 64:
raise ValueError("charmap must be 64 characters in length")
if len(set(charmap)) != 64:
raise ValueError("charmap must not contain duplicate characters")
self.bytemap = charmap
self._encode64 = charmap.__getitem__
lookup = dict((value, idx) for idx, value in enumerate(charmap))
self._decode64 = lookup.__getitem__
# validate big, set appropriate helper functions.
self.big = big
if big:
self._encode_bytes = self._encode_bytes_big
self._decode_bytes = self._decode_bytes_big
else:
self._encode_bytes = self._encode_bytes_little
self._decode_bytes = self._decode_bytes_little