def verify_password(self, guessed_password, tryinverted=True):
"""Check a proposed password, to see if it's able to open and load a
user's account."""
# The cleanest way to see if the password is accurate is to see if it successfully decodes the content in the account.
# We can do this by attempting to decode the private key.
# We can then verify it decoded properly, by re-deriving the public key, and seeing if they match.
test_passkey = self.Keys['master'].get_passkey(guessed_password)
byteprivatekey = base64.b64decode(
self.encryptedprivkey.encode('utf-8'))
# We decoded something. Check to see if we can recreate the pubkey using this.
if byteprivatekey is None:
return False
else:
test_key = Key()
test_key.gpg.import_keys(byteprivatekey)
reconstituted_pubkey = test_key.gpg.export_keys(
test_key.gpg.list_keys()[0]['fingerprint'])
test_key.pubkey = reconstituted_pubkey
test_key._format_keys()
if test_key.pubkey == user.pubkey:
return True
# Let's try one other variation before we give up.
# It's possible the user has caps lock on, and so their keys are inverted.
# Testing this doesn't substantially decrease security, but it does help make things easier for users who had a long day.
# Based on the FB-technique, as described at http://blog.agilebits.com/2011/09/13/facebook-and-caps-lock-unintuitive-security/
if tryinverted:
return self.verify_password(
guessed_password=guessed_password.swapcase(),
tryinverted=False)