def replace_ok(self, response):
        """Handle sslstrip on HTTP responses that contain data.

        This goes through and replaces URLs in the response content.
        """
        resp = util.http.parse_response(response)
        headers = dict(resp.getheaders())
        old_length = int(headers.get("content-length", 0))
        contents = resp.read(old_length)

        new_contents = ""
        prev = 0
        # Not perfect but hopefully close enough.
        urls = re.finditer(
            "https://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\(\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+",
            contents)
        for match in urls:
            url = match.group(0)
            callback = self.build_report_callback(url)
            # strip the https
            url = "http://" + url[8:]
            new_url = ClientReportDetection.add_callback_url(
                callback, url, timeout=20)
            new_contents += contents[prev:match.start()] + new_url
            prev = match.end()
            self.log(
                logging.DEBUG,
                "Replacing %s with %s" % (match.group(0), new_url))
        new_contents += contents[prev:]

        headers["content-length"] = len(new_contents)
        version = "HTTP/1.0" if resp.version == 10 else "HTTP/1.1"

        message = ("{version} 200 OK\r\n" + "\r\n".join(
            [(k, v) % "%s: %s" for k, v in headers.items()]) + "\r\n\r\n" + "{data}")
        data = message.format(version=version, data=new_contents)

        # Handle any extra data in response after the HTTP response
        total_consumed = response.index("\r\n\r\n") + 4 + old_length
        if total_consumed < len(response):
            data += response[total_consumed:]

        return data
dataset/ETHPy150Open google/nogotofail/nogotofail/mitm/connection/handlers/data/http.py/SSLStrip.replace_ok/swapped operands of `%`