Files
2025-12-09 22:30:51 +08:00

333 lines
10 KiB
Python

import torch
from tqdm import tqdm
import random
from ..minigpt_utils import prompt_wrapper, generator
from torchvision.utils import save_image
import matplotlib.pyplot as plt
import seaborn as sns
def normalize(images):
mean = torch.tensor([0.48145466, 0.4578275, 0.40821073]).cuda()
std = torch.tensor([0.26862954, 0.26130258, 0.27577711]).cuda()
images = images - mean[None, :, None, None]
images = images / std[None, :, None, None]
return images
def denormalize(images):
mean = torch.tensor([0.48145466, 0.4578275, 0.40821073]).cuda()
std = torch.tensor([0.26862954, 0.26130258, 0.27577711]).cuda()
images = images * std[None, :, None, None]
images = images + mean[None, :, None, None]
return images
class Attacker:
def __init__(self, args, model, targets, device="cuda:0", is_rtp=False):
self.args = args
self.model = model
self.device = device
self.is_rtp = is_rtp
self.targets = targets
self.num_targets = len(targets)
self.loss_buffer = []
# freeze and set to eval model:
self.model.eval()
self.model.requires_grad_(False)
def attack_unconstrained(
self, text_prompt, img, batch_size=8, num_iter=2000, alpha=1 / 255
):
print(">>> batch_size:", batch_size)
my_generator = generator.Generator(model=self.model)
adv_noise = torch.rand_like(img).to(self.device) # [0,1]
adv_noise.requires_grad_(
True
) # its gradient will be tracked during backpropagation
adv_noise.retain_grad() # gradient will not be deleted after backpropagation
for t in tqdm(range(num_iter + 1)):
batch_targets = random.sample(self.targets, batch_size)
text_prompts = [text_prompt] * batch_size
x_adv = normalize(adv_noise)
# Lines 64~68: Calculate loss for x_adv
prompt = prompt_wrapper.Prompt(
model=self.model, text_prompts=text_prompts, img_prompts=[[x_adv]]
)
prompt.img_embs = prompt.img_embs * batch_size
prompt.update_context_embs()
target_loss = self.attack_loss(prompt, batch_targets)
target_loss.backward()
adv_noise.data = (
adv_noise.data - alpha * adv_noise.grad.detach().sign()
).clamp(0, 1)
adv_noise.grad.zero_()
self.model.zero_grad()
self.loss_buffer.append(target_loss.item())
print("target_loss: %f" % (target_loss.item()))
if t % 20 == 0:
self.plot_loss()
if t % 100 == 0:
print("######### Output - Iter = %d ##########" % t)
x_adv = normalize(adv_noise)
prompt.update_img_prompts([[x_adv]])
prompt.img_embs = prompt.img_embs * batch_size
prompt.update_context_embs()
with torch.no_grad():
response, _ = my_generator.generate(prompt)
print(">>>", response)
adv_img_prompt = denormalize(x_adv).detach().cpu()
adv_img_prompt = adv_img_prompt.squeeze(0)
save_image(
adv_img_prompt,
"%s/bad_prompt_temp_%d.bmp" % (self.args.save_dir, t),
)
return adv_img_prompt
def attack_constrained(
self,
text_prompt,
img,
batch_size=8,
num_iter=2000,
alpha=1 / 255,
epsilon=128 / 255,
):
print(">>> batch_size:", batch_size)
my_generator = generator.Generator(model=self.model)
adv_noise = torch.rand_like(img).to(self.device) * 2 * epsilon - epsilon
x = denormalize(img).clone().to(self.device)
adv_noise.data = (adv_noise.data + x.data).clamp(0, 1) - x.data
adv_noise.requires_grad_(True)
adv_noise.retain_grad()
for t in tqdm(range(num_iter + 1)):
batch_targets = random.sample(self.targets, batch_size)
text_prompts = [text_prompt] * batch_size
x_adv = x + adv_noise
x_adv = normalize(x_adv)
prompt = prompt_wrapper.Prompt(
model=self.model, text_prompts=text_prompts, img_prompts=[[x_adv]]
)
prompt.img_embs = prompt.img_embs * batch_size
prompt.update_context_embs()
target_loss = self.attack_loss(prompt, batch_targets)
target_loss.backward()
adv_noise.data = (
adv_noise.data - alpha * adv_noise.grad.detach().sign()
).clamp(-epsilon, epsilon)
adv_noise.data = (adv_noise.data + x.data).clamp(0, 1) - x.data
adv_noise.grad.zero_()
self.model.zero_grad()
self.loss_buffer.append(target_loss.item())
print("target_loss: %f" % (target_loss.item()))
if t % 20 == 0:
self.plot_loss()
if t % 100 == 0:
print("######### Output - Iter = %d ##########" % t)
x_adv = x + adv_noise
x_adv = normalize(x_adv)
prompt.update_img_prompts([[x_adv]])
prompt.img_embs = prompt.img_embs * batch_size
prompt.update_context_embs()
with torch.no_grad():
response, _ = my_generator.generate(prompt)
print(">>>", response)
adv_img_prompt = denormalize(x_adv).detach().cpu()
adv_img_prompt = adv_img_prompt.squeeze(0)
save_image(
adv_img_prompt,
"%s/bad_prompt_temp_%d.bmp" % (self.args.save_dir, t),
)
return adv_img_prompt
def plot_loss(self):
sns.set_theme()
num_iters = len(self.loss_buffer)
x_ticks = list(range(0, num_iters))
# Plot and label the training and validation loss values
plt.plot(x_ticks, self.loss_buffer, label="Target Loss")
# Add in a title and axes labels
plt.title("Loss Plot")
plt.xlabel("Iters")
plt.ylabel("Loss")
# Display the plot
plt.legend(loc="best")
plt.savefig("%s/loss_curve.png" % (self.args.save_dir))
plt.clf()
torch.save(self.loss_buffer, "%s/loss" % (self.args.save_dir))
def attack_loss(self, prompts, targets):
context_embs = prompts.context_embs
if len(context_embs) == 1:
context_embs = context_embs * len(targets) # expand to fit the batch_size
assert len(context_embs) == len(
targets
), f"Unmathced batch size of prompts and targets {len(context_embs)} != {len(targets)}"
batch_size = len(targets)
self.model.llama_tokenizer.padding_side = "right"
to_regress_tokens = self.model.llama_tokenizer(
targets,
return_tensors="pt",
padding="longest",
truncation=True,
max_length=self.model.max_txt_len,
add_special_tokens=False,
).to(self.device)
to_regress_embs = self.model.llama_model.model.embed_tokens(
to_regress_tokens.input_ids
)
bos = (
torch.ones(
[1, 1],
dtype=to_regress_tokens.input_ids.dtype,
device=to_regress_tokens.input_ids.device,
)
* self.model.llama_tokenizer.bos_token_id
)
bos_embs = self.model.llama_model.model.embed_tokens(bos)
pad = (
torch.ones(
[1, 1],
dtype=to_regress_tokens.input_ids.dtype,
device=to_regress_tokens.input_ids.device,
)
* self.model.llama_tokenizer.pad_token_id
)
pad_embs = self.model.llama_model.model.embed_tokens(pad)
T = to_regress_tokens.input_ids.masked_fill(
to_regress_tokens.input_ids == self.model.llama_tokenizer.pad_token_id, -100
)
pos_padding = torch.argmin(
T, dim=1
) # a simple trick to find the start position of padding
input_embs = []
targets_mask = []
target_tokens_length = []
context_tokens_length = []
seq_tokens_length = []
for i in range(batch_size):
pos = int(pos_padding[i])
if T[i][pos] == -100:
target_length = pos
else:
target_length = T.shape[1]
targets_mask.append(T[i : i + 1, :target_length])
input_embs.append(
to_regress_embs[i : i + 1, :target_length]
) # omit the padding tokens
context_length = context_embs[i].shape[1]
seq_length = target_length + context_length
target_tokens_length.append(target_length)
context_tokens_length.append(context_length)
seq_tokens_length.append(seq_length)
max_length = max(seq_tokens_length)
attention_mask = []
for i in range(batch_size):
# masked out the context from loss computation
context_mask = (
torch.ones([1, context_tokens_length[i] + 1], dtype=torch.long)
.to(self.device)
.fill_(-100) # plus one for bos
)
# padding to align the length
num_to_pad = max_length - seq_tokens_length[i]
padding_mask = (
torch.ones([1, num_to_pad], dtype=torch.long)
.to(self.device)
.fill_(-100)
)
targets_mask[i] = torch.cat(
[context_mask, targets_mask[i], padding_mask], dim=1
)
input_embs[i] = torch.cat(
[
bos_embs,
context_embs[i],
input_embs[i],
pad_embs.repeat(1, num_to_pad, 1),
],
dim=1,
)
attention_mask.append(
torch.LongTensor([[1] * (1 + seq_tokens_length[i]) + [0] * num_to_pad])
)
targets = torch.cat(targets_mask, dim=0).to(self.device)
inputs_embs = torch.cat(input_embs, dim=0).to(self.device)
attention_mask = torch.cat(attention_mask, dim=0).to(self.device)
outputs = self.model.llama_model(
inputs_embeds=inputs_embs,
attention_mask=attention_mask,
return_dict=True,
labels=targets,
)
loss = outputs.loss
return loss