epicyon/auth.py

161 lines
5.7 KiB
Python

__filename__ = "auth.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "1.1.0"
__maintainer__ = "Bob Mottram"
__email__ = "bob@freedombone.net"
__status__ = "Production"
import base64
import hashlib
import binascii
import os
import random
def hashPassword(password: str) -> str:
"""Hash a password for storing
"""
salt = hashlib.sha256(os.urandom(60)).hexdigest().encode('ascii')
pwdhash = hashlib.pbkdf2_hmac('sha512',
password.encode('utf-8'),
salt, 100000)
pwdhash = binascii.hexlify(pwdhash)
return (salt + pwdhash).decode('ascii')
def verifyPassword(storedPassword: str, providedPassword: str) -> bool:
"""Verify a stored password against one provided by user
"""
salt = storedPassword[:64]
storedPassword = storedPassword[64:]
pwdhash = hashlib.pbkdf2_hmac('sha512',
providedPassword.encode('utf-8'),
salt.encode('ascii'),
100000)
pwdhash = binascii.hexlify(pwdhash).decode('ascii')
return pwdhash == storedPassword
def createBasicAuthHeader(nickname: str, password: str) -> str:
"""This is only used by tests
"""
authStr = nickname.replace('\n', '') + ':' + password.replace('\n', '')
return 'Basic ' + base64.b64encode(authStr.encode('utf-8')).decode('utf-8')
def authorizeBasic(baseDir: str, path: str, authHeader: str,
debug: bool) -> bool:
"""HTTP basic auth
"""
if ' ' not in authHeader:
if debug:
print('DEBUG: Authorixation header does not ' +
'contain a space character')
return False
if '/users/' not in path and \
'/channel/' not in path and \
'/profile/' not in path:
if debug:
print('DEBUG: Path for Authorization does not contain a user')
return False
pathUsersSection = path.split('/users/')[1]
if '/' not in pathUsersSection:
if debug:
print('DEBUG: This is not a users endpoint')
return False
nicknameFromPath = pathUsersSection.split('/')[0]
base64Str = authHeader.split(' ')[1].replace('\n', '')
plain = base64.b64decode(base64Str).decode('utf-8')
if ':' not in plain:
if debug:
print('DEBUG: Basic Auth header does not contain a ":" ' +
'separator for username:password')
return False
nickname = plain.split(':')[0]
if nickname != nicknameFromPath:
if debug:
print('DEBUG: Nickname given in the path (' + nicknameFromPath +
') does not match the one in the Authorization header (' +
nickname + ')')
return False
passwordFile = baseDir+'/accounts/passwords'
if not os.path.isfile(passwordFile):
if debug:
print('DEBUG: passwords file missing')
return False
providedPassword = plain.split(':')[1]
passfile = open(passwordFile, "r")
for line in passfile:
if line.startswith(nickname+':'):
storedPassword = line.split(':')[1].replace('\n', '')
success = verifyPassword(storedPassword, providedPassword)
if not success:
if debug:
print('DEBUG: Password check failed for ' + nickname)
return success
print('DEBUG: Did not find credentials for ' + nickname +
' in ' + passwordFile)
return False
def storeBasicCredentials(baseDir: str, nickname: str, password: str) -> bool:
"""Stores login credentials to a file
"""
if ':' in nickname or ':' in password:
return False
nickname = nickname.replace('\n', '').strip()
password = password.replace('\n', '').strip()
if not os.path.isdir(baseDir + '/accounts'):
os.mkdir(baseDir + '/accounts')
passwordFile = baseDir + '/accounts/passwords'
storeStr = nickname + ':' + hashPassword(password)
if os.path.isfile(passwordFile):
if nickname + ':' in open(passwordFile).read():
with open(passwordFile, "r") as fin:
with open(passwordFile + '.new', "w") as fout:
for line in fin:
if not line.startswith(nickname + ':'):
fout.write(line)
else:
fout.write(storeStr + '\n')
os.rename(passwordFile + '.new', passwordFile)
else:
# append to password file
with open(passwordFile, "a") as passfile:
passfile.write(storeStr + '\n')
else:
with open(passwordFile, "w") as passfile:
passfile.write(storeStr + '\n')
return True
def removePassword(baseDir: str, nickname: str) -> None:
"""Removes the password entry for the given nickname
This is called during account removal
"""
passwordFile = baseDir + '/accounts/passwords'
if os.path.isfile(passwordFile):
with open(passwordFile, "r") as fin:
with open(passwordFile + '.new', "w") as fout:
for line in fin:
if not line.startswith(nickname + ':'):
fout.write(line)
os.rename(passwordFile + '.new', passwordFile)
def authorize(baseDir: str, path: str, authHeader: str, debug: bool) -> bool:
"""Authorize using http header
"""
if authHeader.lower().startswith('basic '):
return authorizeBasic(baseDir, path, authHeader, debug)
return False
def createPassword(length=10):
validChars = 'abcdefghijklmnopqrstuvwxyz' + \
'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'
return ''.join((random.choice(validChars) for i in range(length)))