Eos/eos/base/election.py

165 lines
5.0 KiB
Python

# Eos - Verifiable elections
# Copyright © 2017 RunasSudo (Yingtong Li)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
from eos.core.objects import *
from eos.base.workflow import *
class Answer(EmbeddedObject):
pass
class EncryptedAnswer(EmbeddedObject):
pass
class NullEncryptedAnswer(EncryptedAnswer):
answer = EmbeddedObjectField()
def decrypt(self):
return None, self.answer
class Ballot(EmbeddedObject):
#_id = UUIDField()
encrypted_answers = EmbeddedObjectListField()
election_id = UUIDField()
election_hash = StringField()
answers = EmbeddedObjectListField(is_hashed=False)
def deaudit(self):
encrypted_answers_deaudit = EosList()
for encrypted_answer in self.encrypted_answers:
encrypted_answers_deaudit.append(encrypted_answer.deaudit())
return Ballot(encrypted_answers=encrypted_answers_deaudit, election_id=self.election_id, election_hash=self.election_hash)
class Vote(EmbeddedObject):
ballot = EmbeddedObjectField()
cast_at = DateTimeField()
class Voter(EmbeddedObject):
_id = UUIDField()
votes = EmbeddedObjectListField()
class User(EmbeddedObject):
pass
def generate_password():
if is_python:
#__pragma__('skip')
import random
return ''.join(random.SystemRandom().choices('23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz', k=12))
#__pragma__('noskip')
else:
return None
class EmailUser(User):
name = StringField()
email = StringField(is_protected=True)
password = StringField(is_protected=True, default=generate_password)
def matched_by(self, other):
if not isinstance(other, EmailUser):
return False
return self.email.lower() == other.email.lower() and self.password == other.password
def send_email(self, host, port, username, password, from_email, content):
#__pragma__('skip')
import smtplib
#__pragma__('noskip')
with smtplib.SMTP(host, port) as smtp:
if username is not None:
smtp.login(username, password)
smtp.sendmail(from_email, [self.email], content)
def email_password(self, host, port, username, password, from_email):
self.send_email(host, port, username, password, from_email, 'Subject: Registered to vote in {1}\nFrom: {4}\nTo: {2}\n\nDear {0},\n\nYou are registered to vote in the election {1}. Your log in details are as follows:\n\nEmail: {2}\nPassword: {3}'.format(self.name, self.recurse_parents(Election).name, self.email, self.password, from_email))
class UserVoter(Voter):
user = EmbeddedObjectField()
@property
def name(self):
return self.user.name
class Question(EmbeddedObject):
prompt = StringField()
class Result(EmbeddedObject):
pass
class ApprovalQuestion(Question):
choices = ListField(StringField())
min_choices = IntField()
max_choices = IntField()
def pretty_answer(self, answer):
return ', '.join([self.choices[choice] for choice in answer.choices])
class ApprovalAnswer(Answer):
choices = ListField(IntField())
class PreferentialQuestion(Question):
choices = ListField(StringField())
min_choices = IntField()
max_choices = IntField()
def pretty_answer(self, answer):
return ', '.join([self.choices[choice] for choice in answer.choices])
class PreferentialAnswer(Answer):
choices = ListField(IntField())
class RawResult(Result):
_ver = StringField(default='0.2')
plaintexts = ListField(EmbeddedObjectListField())
answers = EmbeddedObjectListField()
def count(self):
combined = []
for answer in self.answers:
index = next((i for i, val in enumerate(combined) if val[0] == answer), None)
if index is None:
combined.append([answer, 1])
else:
combined[index][1] += 1
combined.sort(key=lambda x: x[1], reverse=True)
return combined
class Election(TopLevelObject):
_ver = StringField(default='0.2')
_id = UUIDField()
workflow = EmbeddedObjectField(Workflow) # Once saved, we don't care what kind of workflow it is
name = StringField()
kind = StringField(default='election')
voters = EmbeddedObjectListField(is_hashed=False)
questions = EmbeddedObjectListField()
results = EmbeddedObjectListField(is_hashed=False)
def verify(self):
#__pragma__('skip')
from eos.core.hashing import SHA256
#__pragma__('noskip')
election_hash = SHA256().update_obj(self).hash_as_b64()
for voter in self.voters:
for vote in voter.votes:
if vote.ballot.election_id != self._id:
raise Exception('Invalid election ID on ballot')
if vote.ballot.election_hash != election_hash:
raise Exception('Invalid election hash on ballot')