Issue when trying to send and receive data before fuzzing

[I C]

Hello,

For the protocol I'm fuzzing, I need to retrieve a session handle which will be reused in the fuzzed requests.

I first tried to use pre_send with the following code:

...

but I don't see my request being sent during the fuzzing.

After that, I tried to use pre_send_callbacks method in the session.

Now I see my request but I didn't find how to use the answer in the fuzzed request.

In the example with callback I've seen, node and edge are passed to the callback function and they can be used to replace part of the request before sending.

However, when I try to pass node and edge to my pre_send_callbacks method, I get this error:

Is there a way to do what I want with pre_send or pre_send_callbacks ?

Or another solution entirely ?

Thank you

[I C]

it looks like the image I attached were removed so I'll add the code here.

For my attempt using pre_send:

def register_session2(target, fuzz_data_logger, session):

    #register session

    Command = 0x0065

    Length = 0x04

    SessionHandle = 0x00000000

    Status = 0x00000000

    SenderContext = 0x0000000000000000

    Options = 0x00000000

    ProtocolVersion = 0x0001

    OptionFlags = 0x0000

    RegisterSessionReq = struct.pack('<hhiiqihh' , Command, Length, SessionHandle, Status, SenderContext, Options, ProtocolVersion, OptionFlags)

    target.send(RegisterSessionReq)

    RegisterSessionRsp = target.recv(10000)

    SessionHandle = RegisterSessionRsp[4:8]

...

session.pre_send = register_session2

session.connect(s_get("Get Attribute"))  

session.fuzz()

and for the attempt using pre_send_callbacks:

def register_session(target, fuzz_data_logger, session, node, edge, *args, **kwargs):

    #register session

    Command = 0x0065

    Length = 0x04

    SessionHandle = 0x00000000

    Status = 0x00000000

    SenderContext = 0x0000000000000000

    Options = 0x00000000

    ProtocolVersion = 0x0001

    OptionFlags = 0x0000

    RegisterSessionReq = struct.pack('<hhiiqihh' , Command, Length, SessionHandle, Status, SenderContext, Options, ProtocolVersion, OptionFlags)

    target.send(RegisterSessionReq)

    RegisterSessionRsp = target.recv(10000)

    SessionHandle = RegisterSessionRsp[4:8]

error is:

Error!!!! A custom pre_send callback function raised an uncought error.

Traceback (most recent call last):

  File "C:\Program Files\Python38\lib\site-packages\boofuzz\monitors\callback_monitor.py", line 44, in pre_send

    f(target=target, fuzz_data_logger=fuzz_data_logger, session=session, sock=target)

TypeError: register_session() missing 2 required positional arguments: 'node' and 'edge'

if I remove node and edge from the parameters of the pre_callback function, my pre-request is sent but I'm not able to use the results in the nodes.

[joshua.t...@gmail.com]

Hello! From what you've described, it's hard to debug with precision. However, it looks like you can get the data successfully, in which case you might just store it in a global variable, which you then use in the node-specific callback method.