def data_mnist(datadir=tempfile.gettempdir(), train_start=0,
train_end=60000, test_start=0, test_end=10000):
warnings.warn(utils_mnist_warning)
mnist = dataset.MNIST(train_start=train_start,
train_end=train_end,
test_start=test_start,
test_end=test_end,
center=False)
return mnist.get_set('train') + mnist.get_set('test')
def zoo(viz_enabled=VIZ_ENABLED,
nb_epochs=NB_EPOCHS,
batch_size=BATCH_SIZE,
source_samples=SOURCE_SAMPLES,
learning_rate=LEARNING_RATE,
attack_iterations=ATTACK_ITERATIONS,
model_path=MODEL_PATH,
targeted=TARGETED):
"""
:param viz_enabled: (boolean) activate plots of adversarial examples
:param nb_epochs: number of epochs to train model
:param batch_size: size of training batches
:param nb_classes: number of output classes
:param source_samples: number of test inputs to attack
:param learning_rate: learning rate for training
:param model_path: path to the model file
:param targeted: should we run a targeted attack? or untargeted?
:return: an AccuracyReport object
"""
# Object used to keep track of (and return) key accuracies
report = AccuracyReport()
# Set TF random seed to improve reproducibility
tf.set_random_seed(1234)
# Create TF session
sess = tf.Session()
print("Created TensorFlow session.")
set_log_level(logging.DEBUG)
if DATASET == 'MNIST':
train_start = 0
train_end = 60000
test_start = 0
test_end = 10000
ds = dataset.MNIST(train_start=train_start,
train_end=train_end,
test_start=test_start,
test_end=test_end,
center=False)
elif DATASET == 'SVHN':
train_start = 0
train_end = 73257
test_start = 0
test_end = 26032
ds = dataset.SVHN(train_start=train_start,
train_end=train_end,
test_start=test_start,
test_end=test_end)
elif DATASET == 'CIFAR10':
train_start = 0
train_end = 60000
test_start = 0
test_end = 10000
ds = dataset.CIFAR10(train_start=train_start,
train_end=train_end,
test_start=test_start,
test_end=test_end,
center=False)
x_train, y_train, x_test, y_test = ds.get_set('train') + ds.get_set('test')
# Obtain Image Parameters
img_rows, img_cols, nchannels = x_train.shape[1:4]
nb_classes = y_train.shape[1]
# Define input TF placeholder
x = tf.placeholder(tf.float32, shape=(None, img_rows, img_cols, nchannels))
y = tf.placeholder(tf.float32, shape=(None, nb_classes))
nb_filters = 64
# Define TF model graph
model = ModelBasicCNN(DATASET, nb_classes, nb_filters,
(None, img_rows, img_cols, nchannels))
preds = model.get_logits(x)
loss = CrossEntropy(model, smoothing=0.1)
print("Defined TensorFlow model graph.")
###########################################################################
# Training the model using TensorFlow
###########################################################################
# Train an MNIST model
train_params = {
'nb_epochs': nb_epochs,
'batch_size': batch_size,
'learning_rate': learning_rate,
'filename': os.path.split(model_path)[-1]
}
rng = np.random.RandomState([2018, 10, 22])
# check if we've trained before, and if we have, use that pre-trained model
if os.path.exists(model_path + ".meta"):
tf_model_load(sess, model_path)
else:
train(sess, loss, x, y, x_train, y_train, args=train_params, rng=rng)
saver = tf.train.Saver()
saver.save(sess, model_path)
# Evaluate the accuracy of the MNIST model on legitimate test examples
eval_params = {'batch_size': batch_size}
accuracy = model_eval(sess, x, y, preds, x_test, y_test, args=eval_params)
assert x_test.shape[0] == test_end - test_start, x_test.shape
print('Test accuracy on legitimate test examples: {0}'.format(accuracy))
report.clean_train_clean_eval = accuracy
###########################################################################
# Craft adversarial examples using Carlini and Wagner's approach
###########################################################################
nb_adv_per_sample = str(nb_classes - 1) if targeted else '1'
print('Crafting ' + str(source_samples) + ' * ' + nb_adv_per_sample +
' adversarial examples')
print("This could take some time ...")
# Instantiate a Zoo attack object
zoo = Zoo(model, sess=sess)
if viz_enabled:
assert source_samples == nb_classes
idxs = [
np.where(np.argmax(y_test, axis=1) == i)[0][0]
for i in range(nb_classes)
]
if targeted:
if viz_enabled:
# Initialize our array for grid visualization
grid_shape = (nb_classes, nb_classes, img_rows, img_cols,
nchannels)
grid_viz_data = np.zeros(grid_shape, dtype='f')
adv_inputs = np.array([[instance] * nb_classes
for instance in x_test[idxs]],
dtype=np.float32)
else:
adv_inputs = np.array([[instance] * nb_classes
for instance in x_test[:source_samples]],
dtype=np.float32)
one_hot = np.zeros((nb_classes, nb_classes))
one_hot[np.arange(nb_classes), np.arange(nb_classes)] = 1
adv_inputs = adv_inputs.reshape(
(source_samples * nb_classes, img_rows, img_cols, nchannels))
adv_ys = np.array([one_hot] * source_samples,
dtype=np.float32).reshape(
(source_samples * nb_classes, nb_classes))
yname = "y_target"
else:
if viz_enabled:
# Initialize our array for grid visualization
grid_shape = (nb_classes, 2, img_rows, img_cols, nchannels)
grid_viz_data = np.zeros(grid_shape, dtype='f')
adv_inputs = x_test[idxs]
else:
adv_inputs = x_test[:source_samples]
adv_ys = None
yname = "y"
zoo_params = {
'binary_search_steps': BINARY_SEARCH_STEPS,
yname: adv_ys,
'max_iterations': attack_iterations,
'learning_rate': ZOO_LEARNING_RATE,
'batch_size':
source_samples * nb_classes if targeted else source_samples,
'initial_const': INIT_CONST,
'solver': SOLVER,
'image_shape': [img_rows, img_cols, nchannels],
'nb_classes': nb_classes
}
adv = zoo.generate_np(adv_inputs, **zoo_params)
eval_params = {'batch_size': np.minimum(nb_classes, source_samples)}
if targeted:
adv_accuracy = model_eval(sess,
x,
y,
preds,
adv,
adv_ys,
args=eval_params)
else:
if viz_enabled:
adv_accuracy = 1 - model_eval(
sess, x, y, preds, adv, y_test[idxs], args=eval_params)
else:
adv_accuracy = 1 - model_eval(sess,
x,
y,
preds,
adv,
y_test[:source_samples],
args=eval_params)
if viz_enabled:
for j in range(nb_classes):
if targeted:
for i in range(nb_classes):
grid_viz_data[i, j] = adv[i * nb_classes + j]
else:
grid_viz_data[j, 0] = adv_inputs[j]
grid_viz_data[j, 1] = adv[j]
print(grid_viz_data.shape)
print('--------------------------------------')
# Compute the number of adversarial examples that were successfully found
print('Avg. rate of successful adv. examples {0:.4f}'.format(adv_accuracy))
report.clean_train_adv_eval = 1. - adv_accuracy
# Compute the average distortion introduced by the algorithm
percent_perturbed = np.mean(
np.sum((adv - adv_inputs)**2, axis=(1, 2, 3))**.5)
print('Avg. L_2 norm of perturbations {0:.4f}'.format(percent_perturbed))
# Close TF session
sess.close()
# Finally, block & display a grid of all the adversarial examples
if viz_enabled:
_ = grid_visual(grid_viz_data)
return report