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mirror of https://github.com/etesync/server synced 2024-11-16 05:48:59 +00:00
etesync-server/django_etebase/serializers.py
Tom Hacohen 9a518b3907 Chunks: add error handling for chunks having content or not existing.
If the chunk already has a content and we try to upload it again, we
assume the previous content was correct and this one is the same
(chunks are immutable). We can't actually ensure they are the same due
to the encryption, though they should be.

If a chunk is being uploaded for the first time and doesn't have a
content, throw a validation error rather than throwing an ugly error.
2020-07-10 09:29:21 +03:00

456 lines
15 KiB
Python

# Copyright © 2017 Tom Hacohen
#
# 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, version 3.
#
# This library 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import base64
from django.core.files.base import ContentFile
from django.core import exceptions as django_exceptions
from django.contrib.auth import get_user_model
from django.db import transaction
from rest_framework import serializers
from . import models
User = get_user_model()
def process_revisions_for_item(item, revision_data):
chunks_objs = []
chunks = revision_data.pop('chunks_relation')
for chunk in chunks:
uid = chunk[0]
chunk_obj = models.CollectionItemChunk.objects.filter(uid=uid).first()
if len(chunk) > 1:
content = chunk[1]
# If the chunk already exists we assume it's fine. Otherwise, we upload it.
if chunk_obj is None:
chunk_obj = models.CollectionItemChunk(uid=uid, item=item)
chunk_obj.chunkFile.save('IGNORED', ContentFile(content))
chunk_obj.save()
else:
if chunk_obj is None:
raise serializers.ValidationError('Tried to create a new chunk without content')
chunks_objs.append(chunk_obj)
stoken = models.Stoken.objects.create()
revision = models.CollectionItemRevision.objects.create(**revision_data, item=item, stoken=stoken)
for chunk in chunks_objs:
models.RevisionChunkRelation.objects.create(chunk=chunk, revision=revision)
return revision
def b64encode(value):
return base64.urlsafe_b64encode(value).decode('ascii').strip('=')
def b64decode(data):
data += "=" * ((4 - len(data) % 4) % 4)
return base64.urlsafe_b64decode(data)
def b64decode_or_bytes(data):
if isinstance(data, bytes):
return data
else:
return b64decode(data)
class BinaryBase64Field(serializers.Field):
def to_representation(self, value):
return value
def to_internal_value(self, data):
return b64decode_or_bytes(data)
class CollectionEncryptionKeyField(BinaryBase64Field):
def get_attribute(self, instance):
request = self.context.get('request', None)
if request is not None:
return instance.members.get(user=request.user).encryptionKey
return None
class CollectionContentField(BinaryBase64Field):
def get_attribute(self, instance):
request = self.context.get('request', None)
if request is not None:
return instance.members.get(user=request.user).encryptionKey
return None
class ChunksField(serializers.RelatedField):
def to_representation(self, obj):
obj = obj.chunk
if self.context.get('prefetch'):
with open(obj.chunkFile.path, 'rb') as f:
return (obj.uid, f.read())
else:
return (obj.uid, )
def to_internal_value(self, data):
if data[0] is None or data[1] is None:
raise serializers.ValidationError('null is not allowed')
return (data[0], b64decode_or_bytes(data[1]))
class CollectionItemChunkSerializer(serializers.ModelSerializer):
class Meta:
model = models.CollectionItemChunk
fields = ('uid', 'chunkFile')
class CollectionItemRevisionSerializer(serializers.ModelSerializer):
chunks = ChunksField(
source='chunks_relation',
queryset=models.RevisionChunkRelation.objects.all(),
many=True
)
meta = BinaryBase64Field()
class Meta:
model = models.CollectionItemRevision
fields = ('chunks', 'meta', 'uid', 'deleted')
class CollectionItemSerializer(serializers.ModelSerializer):
encryptionKey = BinaryBase64Field(required=False, default=None, allow_null=True)
etag = serializers.CharField(allow_null=True, write_only=True)
content = CollectionItemRevisionSerializer(many=False)
class Meta:
model = models.CollectionItem
fields = ('uid', 'version', 'encryptionKey', 'content', 'etag')
def create(self, validated_data):
"""Function that's called when this serializer creates an item"""
validate_etag = self.context.get('validate_etag', False)
etag = validated_data.pop('etag')
revision_data = validated_data.pop('content')
uid = validated_data.pop('uid')
Model = self.__class__.Meta.model
with transaction.atomic():
instance, created = Model.objects.get_or_create(uid=uid, defaults=validated_data)
cur_etag = instance.etag if not created else None
if validate_etag and cur_etag != etag:
raise serializers.ValidationError('Wrong etag. Expected {} got {}'.format(cur_etag, etag))
if not created:
# We don't have to use select_for_update here because the unique constraint on current guards against
# the race condition. But it's a good idea because it'll lock and wait rather than fail.
current_revision = instance.revisions.filter(current=True).select_for_update().first()
current_revision.current = None
current_revision.save()
process_revisions_for_item(instance, revision_data)
return instance
def update(self, instance, validated_data):
# We never update, we always update in the create method
raise NotImplementedError()
class CollectionItemDepSerializer(serializers.ModelSerializer):
etag = serializers.CharField()
class Meta:
model = models.CollectionItem
fields = ('uid', 'etag')
def validate(self, data):
item = self.__class__.Meta.model.objects.get(uid=data['uid'])
etag = data['etag']
if item.etag != etag:
raise serializers.ValidationError('Wrong etag. Expected {} got {}'.format(item.etag, etag))
return data
class CollectionItemBulkGetSerializer(serializers.ModelSerializer):
etag = serializers.CharField(required=False)
class Meta:
model = models.CollectionItem
fields = ('uid', 'etag')
class CollectionSerializer(serializers.ModelSerializer):
collectionKey = CollectionEncryptionKeyField()
accessLevel = serializers.SerializerMethodField('get_access_level_from_context')
stoken = serializers.CharField(read_only=True)
uid = serializers.CharField(source='main_item.uid')
encryptionKey = BinaryBase64Field(source='main_item.encryptionKey', required=False, default=None, allow_null=True)
etag = serializers.CharField(allow_null=True, write_only=True)
version = serializers.IntegerField(min_value=0, source='main_item.version')
content = CollectionItemRevisionSerializer(many=False, source='main_item.content')
class Meta:
model = models.Collection
fields = ('uid', 'version', 'accessLevel', 'encryptionKey', 'collectionKey', 'content', 'stoken', 'etag')
def get_access_level_from_context(self, obj):
request = self.context.get('request', None)
if request is not None:
return obj.members.get(user=request.user).accessLevel
return None
def create(self, validated_data):
"""Function that's called when this serializer creates an item"""
collection_key = validated_data.pop('collectionKey')
etag = validated_data.pop('etag')
main_item_data = validated_data.pop('main_item')
uid = main_item_data.pop('uid')
version = main_item_data.pop('version')
revision_data = main_item_data.pop('content')
encryption_key = main_item_data.pop('encryptionKey')
instance = self.__class__.Meta.model(**validated_data)
with transaction.atomic():
if etag is not None:
raise serializers.ValidationError('etag is not None')
instance.save()
main_item = models.CollectionItem.objects.create(
uid=uid, encryptionKey=encryption_key, version=version, collection=instance)
instance.main_item = main_item
instance.save()
process_revisions_for_item(main_item, revision_data)
models.CollectionMember(collection=instance,
stoken=models.Stoken.objects.create(),
user=validated_data.get('owner'),
accessLevel=models.AccessLevels.ADMIN,
encryptionKey=collection_key,
).save()
return instance
def update(self, instance, validated_data):
raise NotImplementedError()
class CollectionMemberSerializer(serializers.ModelSerializer):
username = serializers.SlugRelatedField(
source='user',
slug_field=User.USERNAME_FIELD,
queryset=User.objects
)
class Meta:
model = models.CollectionMember
fields = ('username', 'accessLevel')
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
with transaction.atomic():
# We only allow updating accessLevel
access_level = validated_data.pop('accessLevel')
if instance.accessLevel != access_level:
instance.stoken = models.Stoken.objects.create()
instance.accessLevel = access_level
instance.save()
return instance
class CollectionInvitationSerializer(serializers.ModelSerializer):
username = serializers.SlugRelatedField(
source='user',
slug_field=User.USERNAME_FIELD,
queryset=User.objects
)
collection = serializers.CharField(source='collection.uid')
fromPubkey = BinaryBase64Field(source='fromMember.user.userinfo.pubkey', read_only=True)
signedEncryptionKey = BinaryBase64Field()
class Meta:
model = models.CollectionInvitation
fields = ('username', 'uid', 'collection', 'signedEncryptionKey', 'accessLevel', 'fromPubkey', 'version')
def validate_user(self, value):
request = self.context['request']
if request.user == value.lower():
raise serializers.ValidationError('Inviting yourself is not allowed')
return value
def create(self, validated_data):
request = self.context['request']
collection = validated_data.pop('collection')
member = collection.members.get(user=request.user)
with transaction.atomic():
return type(self).Meta.model.objects.create(**validated_data, fromMember=member)
def update(self, instance, validated_data):
with transaction.atomic():
instance.accessLevel = validated_data.pop('accessLevel')
instance.signedEncryptionKey = validated_data.pop('signedEncryptionKey')
instance.save()
return instance
class InvitationAcceptSerializer(serializers.Serializer):
encryptionKey = BinaryBase64Field()
def create(self, validated_data):
with transaction.atomic():
invitation = self.context['invitation']
encryption_key = validated_data.get('encryptionKey')
member = models.CollectionMember.objects.create(
collection=invitation.collection,
stoken=models.Stoken.objects.create(),
user=invitation.user,
accessLevel=invitation.accessLevel,
encryptionKey=encryption_key,
)
models.CollectionMemberRemoved.objects.filter(
user=invitation.user, collection=invitation.collection).delete()
invitation.delete()
return member
def update(self, instance, validated_data):
raise NotImplementedError()
class UserSerializer(serializers.ModelSerializer):
pubkey = BinaryBase64Field(source='userinfo.pubkey')
encryptedContent = BinaryBase64Field(source='userinfo.encryptedContent')
class Meta:
model = User
fields = (User.USERNAME_FIELD, User.EMAIL_FIELD, 'pubkey', 'encryptedContent')
class UserInfoPubkeySerializer(serializers.ModelSerializer):
pubkey = BinaryBase64Field()
class Meta:
model = models.UserInfo
fields = ('pubkey', )
class UserSignupSerializer(serializers.ModelSerializer):
class Meta:
model = User
fields = (User.USERNAME_FIELD, User.EMAIL_FIELD)
extra_kwargs = {
'username': {'validators': []}, # We specifically validate in SignupSerializer
}
class AuthenticationSignupSerializer(serializers.Serializer):
user = UserSignupSerializer(many=False)
salt = BinaryBase64Field()
loginPubkey = BinaryBase64Field()
pubkey = BinaryBase64Field()
encryptedContent = BinaryBase64Field()
def create(self, validated_data):
"""Function that's called when this serializer creates an item"""
user_data = validated_data.pop('user')
with transaction.atomic():
instance, _ = User.objects.get_or_create(**user_data)
if hasattr(instance, 'userinfo'):
raise serializers.ValidationError('User already exists')
instance.set_unusable_password()
try:
instance.clean_fields()
except django_exceptions.ValidationError as e:
raise serializers.ValidationError(e)
# FIXME: send email verification
models.UserInfo.objects.create(**validated_data, owner=instance)
return instance
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationLoginChallengeSerializer(serializers.Serializer):
username = serializers.CharField(required=True)
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationLoginSerializer(serializers.Serializer):
response = BinaryBase64Field()
signature = BinaryBase64Field()
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationLoginInnerSerializer(AuthenticationLoginChallengeSerializer):
challenge = BinaryBase64Field()
host = serializers.CharField()
action = serializers.CharField()
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationChangePasswordInnerSerializer(AuthenticationLoginInnerSerializer):
loginPubkey = BinaryBase64Field()
encryptedContent = BinaryBase64Field()
class Meta:
model = models.UserInfo
fields = ('loginPubkey', 'encryptedContent')
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
with transaction.atomic():
instance.loginPubkey = validated_data.pop('loginPubkey')
instance.encryptedContent = validated_data.pop('encryptedContent')
instance.save()
return instance