standardnotes-fs/api.py

115 lines
4.1 KiB
Python

import hashlib, hmac, json, requests, time
from base64 import b64encode, b64decode
from binascii import hexlify, unhexlify
from Crypto.Cipher import AES
class RESTAPI:
def __init__(self, base_url):
self.base_url = base_url
self.headers = {}
def get(self, route, params=None):
url = self.base_url + route
return requests.get(url, params, headers=self.headers).json()
def post(self, route, data=None):
url = self.base_url + route
return requests.post(url, data, headers=self.headers).json()
def addHeader(self, header):
self.headers.update(header)
class EncryptionHelper:
def pure_generatePasswordAndKey(self, password, pw_salt, pw_cost):
output = hashlib.pbkdf2_hmac('sha512', password.encode(), pw_salt.encode(), pw_cost, dklen=96)
output = hexlify(output).decode()
output_length = len(output)
split_length = output_length // 3
pw = output[0 : split_length]
mk = output[split_length : split_length * 2]
ak = output[split_length * 2 : split_length * 3]
return {'pw': pw, 'mk': mk, 'ak': ak}
def pure_decryptResponseItems(self, response_items, keys):
return [self.pure_decryptItem(item, keys) for item in response_items]
def pure_decryptItem(self, item, keys):
uuid = item['uuid']
content = item['content']
enc_item_key = item['enc_item_key']
if not content:
return item
if content[:3] == '002':
item_key = self.pure_decryptString002(enc_item_key, keys['mk'], keys['ak'], uuid)
item_key_length = len(item_key)
item_ek = item_key[:item_key_length//2]
item_ak = item_key[item_key_length//2:]
dec_content = self.pure_decryptString002(content, item_ek, item_ak, uuid)
else:
print('Invalid protocol version.')
dec_item = item
dec_item['content'] = json.loads(dec_content)
return dec_item
def pure_decryptString002(self, string_to_decrypt, encryption_key, auth_key, uuid):
components = string_to_decrypt.split(':')
version = components[0]
auth_hash = components[1]
local_uuid = components[2]
IV = components[3]
ciphertext = components[4]
if local_uuid != uuid:
print('UUID does not match.')
return
string_to_auth = ':'.join([version, uuid, IV, ciphertext])
local_auth_hash = hmac.new(unhexlify(auth_key), string_to_auth.encode(), 'sha256').digest()
local_auth_hash = hexlify(local_auth_hash).decode()
if local_auth_hash != auth_hash:
print('Message has been tampered with.')
return
cipher = AES.new(unhexlify(encryption_key), AES.MODE_CBC, unhexlify(IV))
result = cipher.decrypt(b64decode(ciphertext))
result = result[:-result[-1]] # remove PKCS#7 padding
return result.decode()
class StandardNotesAPI:
encryption_helper = EncryptionHelper()
base_url = 'https://sync.standardnotes.org'
sync_token = None
def getAuthParamsForEmail(self):
return self.api.get('/auth/params', {'email': self.username})
def signIn(self, password):
pw_info = self.getAuthParamsForEmail()
self.keys = self.encryption_helper.pure_generatePasswordAndKey(password, pw_info['pw_salt'], pw_info['pw_cost'])
res = self.api.post('/auth/sign_in', {'email': self.username, 'password': self.keys['pw']})
self.api.addHeader({'Authorization': 'Bearer ' + res['token']})
def sync(self, dirty_items):
res = self.api.post('/items/sync', {'sync_token': self.sync_token})
print(json.dumps(res))
self.sync_token = res['sync_token']
return self.handleResponseItems(res['retrieved_items'])
def handleResponseItems(self, response_items):
decrypted_items = self.encryption_helper.pure_decryptResponseItems(response_items, self.keys)
return decrypted_items
def __init__(self, username, password):
self.api = RESTAPI(self.base_url)
self.username = username
self.signIn(password)