ABS

This is repository for paper ABS: Scanning Neural Networks for Back-doors by Artificial Brain Stimulation.

The repo contains two parts. The source code of ABS pytorch version used in TrojAI competition and the binary code of ABS tensorflow+keras version.

The source code of ABS pytorch version

This repo include source code of ABS pytorch version.

The source code of ABS pytorch version for TrojAI competition round 1 can be accessed at https://github.com/naiyeleo/ABS/blob/master/TrojAI_competition/round1/abs_pytorch_round1.py Round 1 code is the submission for 20200725T153001 of Perspecta team. This submission has 0.30 cross entropy and 0.91 roc-auc on test set and 0.281 cross entropy loss and 0.92 roc-auc on holdout set.

The source code of ABS pytorch version for TrojAI competition round 5 can be accessed at https://github.com/naiyeleo/ABS/blob/master/TrojAI_competition/round5 Round 5 code is the submission for 20210316T161002 of Perspecta-PurdueRutgers team This submission has 0.32 cross entropy and 0.93 roc-auc and 0.26 cross entropy and 0.95 roc-auc on holdout set.

The binary code of ABS tensorflow+keras version

This repo also include the binary code of ABS tensorflow+keras version

Dependences

Python 2, tensoflow=1.12.0, keras=2.2.4, imageio, numpy, pickle, h5py

File Description

You can edit config.json to change different models and settings for ABS. models contain 20 benign models and 21 compromised models. You can edit config.json to choose different models.

The seed images for CIFAR-10 dataset is in cifar_seed_10.pkl which contains 10 seed images, ABS reads in this file and perform analysis on these data. cifar_seed_50.pkl contains 50 seed images and running ABS on more images can increase stability. The preprossing code of input images is written in preprocess.py. ABS calls cifar.py and to provide your own preprocess function, just change the code in cifar.py.

To run the code, python run_abs.py The program will output highest REASR for the model provided in config.json. Triggers with over 80% REASR is shown imgs folder. deltas and masks store the numpy array for such triggers.

Currently, this version of ABS only work on CIFAR-10 dataset and may not support some structure. Support for more dataset and structure is coming soon.

Currently, ABS assumes the activation layer and conv/dense layer are seperated, i.e. the conv/dense layers do not have activation function and there is an activation layer after each dense/conv layer. Please refer to reformat_model.py to see how to seperate activation layers from conv/dense layer.

Contacts

Yingqi Liu, [email protected]