[Cryptography-dev] Getting Error when updating field on DB with encoded base64 string

[Salvador Munguia]

It works when I encrypt and decode from string in same script, but when sent to DB looks like error with base64 encoding. 

Error: 
Traceback (most recent call last):
  File "tmp2.py", line 82, in <module>
    main(1)
  File "tmp2.py", line 73, in main
    string = getCode(id,'ev_details')
  File "tmp2.py", line 23, in getCode
    result = base64.b64decode(row[0])
  File "/usr/lib/python2.7/base64.py", line 76, in b64decode
    raise TypeError(msg)
TypeError: Incorrect padding

Script: 
#!/usr/bin/python
import zlib,MySQLdb,os,sys,urllib,re
import os,hashlib,base64
from cryptography.fernet import Fernet
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
from Crypto.Cipher import AES
from pbkdf2 import PBKDF2

conn = MySQLdb.connect (host = "localhost",
                        user = "root",
                        passwd = "pass",
                        db = "db")

def getCode(id,tbl):
        sql = "SELECT `details` FROM %s WHERE `id` = %s;" % (tbl,id)
        # print sql
        cursor = conn.cursor ()
        cursor.execute (sql)
        row = cursor.fetchone ()
        result = base64.b64decode(row[0])
        # return row[0]
        return result

def getEncrypt(id,tbl):
        sql = "SELECT `encrypted` FROM %s WHERE `id` = %s;" % (tbl,id)
        # print sql
        cursor = conn.cursor ()
        cursor.execute (sql)
        row = cursor.fetchone ()
        result = base64.b64decode(row[0])
        # result = row[0]
        return result

def encryptMAIN(data,fun):
        password = b"This is the password!"
        # salt = os.urandom(16)
        kdf = PBKDF2HMAC(
        algorithm=hashes.SHA256(),
        length=32,
        salt='42$ahasdkjfha',
        iterations=100000,
        backend=default_backend()
        )
        key = base64.urlsafe_b64encode(kdf.derive(password))
        f = Fernet(key)
        if(fun == 'encrypt'):
                return f.encrypt(b"%s" % (data))
        else:
                return f.decrypt(data)

def encryptDATA(data):
        cipher = encryptMAIN(data,'encrypt')
        return cipher

def decryptDATA(data):
        decoded = encryptMAIN(data,'')
        return decoded

def insertBin(id,data):
        data = '%s' % (data)
        sql = "UPDATE `sec_details` set `encrypted` = '%s' WHERE `id` = %s;" % (data, id)
        # print sql
        cursor = conn.cursor ()
        cursor.execute (sql)
        conn.commit()
        return 1


def main(id):
    string = getCode(id,'ev_details')
    e_out = encryptMAIN(string,'encrypt')
    insertBin(id,e_out)
    print "Original Data: " + string
    string = getEncrypt(id,'sec_details')
    print "Encrypted Data: " + string
    dout = encryptMAIN(string,'')
    print "Decrypted Data: " + dout

main(1)


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