crlf-fixup.py

from burp import IBurpExtender, IHttpListener


class BurpExtender(IBurpExtender, IHttpListener):
    def registerExtenderCallbacks(self, callbacks):
        self.callbacks = callbacks
        callbacks.registerHttpListener(self)

    def processHttpMessage(self, toolFlag, messageIsRequest, message):
        helpers = self.callbacks.getHelpers()
        if not messageIsRequest:
            response = message.getResponse()
            info = helpers.analyzeResponse(response)
            offset = info.getBodyOffset()
            response = helpers.bytesToString(response)
            if response[offset-5:offset] == '\n\r\n\r\n':
                headers = response[:offset-5].split('\n')
                new_response = '\r\n'.join(headers) + '\r\n\r\n' + response[offset:]
                new_response = helpers.stringToBytes(new_response)
                message.setResponse(new_response)