Source code for pyotp
import hashlib
from re import split
from typing import Any, Dict, Sequence
from urllib.parse import parse_qsl, unquote, urlparse
from . import contrib # noqa:F401
from .compat import random
from .hotp import HOTP as HOTP
from .otp import OTP as OTP
from .totp import TOTP as TOTP
def random_base32(length: int = 32, chars: Sequence[str] = list("ABCDEFGHIJKLMNOPQRSTUVWXYZ234567")) -> str:
# Note: the otpauth scheme DOES NOT use base32 padding for secret lengths not divisible by 8.
# Some third-party tools have bugs when dealing with such secrets.
# We might consider warning the user when generating a secret of length not divisible by 8.
if length < 32:
raise ValueError("Secrets should be at least 160 bits")
return "".join(random.choice(chars) for _ in range(length))
def random_hex(length: int = 40, chars: Sequence[str] = list("ABCDEF0123456789")) -> str:
if length < 40:
raise ValueError("Secrets should be at least 160 bits")
return random_base32(length=length, chars=chars)
[docs]def parse_uri(uri: str) -> OTP:
"""
Parses the provisioning URI for the OTP; works for either TOTP or HOTP.
See also:
https://github.com/google/google-authenticator/wiki/Key-Uri-Format
:param uri: the hotp/totp URI to parse
:returns: OTP object
"""
# Secret (to be filled in later)
secret = None
# Data we'll parse to the correct constructor
otp_data: Dict[str, Any] = {}
# Parse with URLlib
parsed_uri = urlparse(unquote(uri))
if parsed_uri.scheme != "otpauth":
raise ValueError("Not an otpauth URI")
# Parse issuer/accountname info
accountinfo_parts = split(":|%3A", parsed_uri.path[1:], maxsplit=1)
if len(accountinfo_parts) == 1:
otp_data["name"] = accountinfo_parts[0]
else:
otp_data["issuer"] = accountinfo_parts[0]
otp_data["name"] = accountinfo_parts[1]
# Parse values
for key, value in parse_qsl(parsed_uri.query):
if key == "secret":
secret = value
elif key == "issuer":
if "issuer" in otp_data and otp_data["issuer"] is not None and otp_data["issuer"] != value:
raise ValueError("If issuer is specified in both label and parameters, it should be equal.")
otp_data["issuer"] = value
elif key == "algorithm":
if value == "SHA1":
otp_data["digest"] = hashlib.sha1
elif value == "SHA256":
otp_data["digest"] = hashlib.sha256
elif value == "SHA512":
otp_data["digest"] = hashlib.sha512
else:
raise ValueError("Invalid value for algorithm, must be SHA1, SHA256 or SHA512")
elif key == "digits":
digits = int(value)
if digits not in [6, 7, 8]:
raise ValueError("Digits may only be 6, 7, or 8")
otp_data["digits"] = digits
elif key == "period":
otp_data["interval"] = int(value)
elif key == "counter":
otp_data["initial_count"] = int(value)
elif key != "image":
raise ValueError("{} is not a valid parameter".format(key))
if not secret:
raise ValueError("No secret found in URI")
# Create objects
if parsed_uri.netloc == "totp":
return TOTP(secret, **otp_data)
elif parsed_uri.netloc == "hotp":
return HOTP(secret, **otp_data)
raise ValueError("Not a supported OTP type")