#!/usr/bin/env python

"""
Copyright (c) 2006-2012 sqlmap developers (http://sqlmap.org/)
See the file 'doc/COPYING' for copying permission
"""

import os
import re

from lib.core.common import singleTimeWarnMessage
from lib.core.enums import DBMS
from lib.core.enums import PRIORITY

__priority__ = PRIORITY.NORMAL

def dependencies():
    singleTimeWarnMessage("tamper script '%s' is only meant to be run against %s" % (os.path.basename(__file__).split(".")[0], DBMS.MYSQL))

def tamper(payload, headers=None):
    """
    Replaces space character after SQL statement with a valid random blank character.
    Afterwards replace character = with LIKE operator

    Example:
        * Input: SELECT id FROM users where id = 1
        * Output: SELECT%09id FROM users where id LIKE 1

    Requirement:
        * MySQL, Blue Coat SGOS with WAF activated as documented in
        https://kb.bluecoat.com/index?page=content&id=FAQ2147

    Tested against:
        * MySQL 5.1, SGOS

    Notes:
        * Useful to bypass Blue Coat's recommended WAF rule configuration
    """

    retVal = payload

    if payload:
        retVal = re.sub(r"(?i)(SELECT|UPDATE|INSERT|DELETE)\s+", r"\g<1>\t", payload)
        retVal = re.sub(r"\s*=\s*", " LIKE ", retVal)

    return retVal