FlieTransfer/client.py

import sys
import socket
from PyQt5.QtWidgets import QApplication, QWidget, QVBoxLayout, QPushButton, QFileDialog, QLineEdit, QLabel, QComboBox
from PyQt5.QtCore import Qt
from Crypto.PublicKey import RSA
from Crypto.Cipher import AES, PKCS1_OAEP
from Crypto.Random import get_random_bytes
from Crypto.Signature import pkcs1_15
from Crypto.Hash import SHA256
from Crypto.Util.Padding import pad
import hashlib
import os

class FileTransferApp(QWidget):
    def __init__(self):
        super().__init__()

        # 生成公钥和私钥
        self.generate_keys_if_not_exists()

        self.init_ui()

    def init_ui(self):
        self.setWindowTitle('文件加密和传输')
        self.setGeometry(100, 100, 400, 300)

        layout = QVBoxLayout()

        self.file_label = QLabel('未选择文件')
        layout.addWidget(self.file_label)

        self.select_button = QPushButton('选择文件')
        self.select_button.clicked.connect(self.select_file)
        layout.addWidget(self.select_button)

        self.server_label = QLabel('服务器 IP:')
        layout.addWidget(self.server_label)

        self.server_ip = QLineEdit(self)
        layout.addWidget(self.server_ip)

        self.server_port_label = QLabel('服务器端口:')
        layout.addWidget(self.server_port_label)

        self.server_port = QLineEdit(self)
        self.server_port.setText('59290')  # 默认端口
        layout.addWidget(self.server_port)

        self.algorithm_label = QLabel('选择加密算法:')
        layout.addWidget(self.algorithm_label)

        self.algorithm_combo = QComboBox(self)
        self.algorithm_combo.addItem('AES')
        layout.addWidget(self.algorithm_combo)

        self.mode_label = QLabel('选择加密模式:')
        layout.addWidget(self.mode_label)

        self.mode_combo = QComboBox(self)
        self.mode_combo.addItem('CBC')
        self.mode_combo.addItem('ECB')
        layout.addWidget(self.mode_combo)

        self.send_button = QPushButton('发送加密文件')
        self.send_button.clicked.connect(self.send_file)
        layout.addWidget(self.send_button)

        self.setLayout(layout)

    def select_file(self):
        options = QFileDialog.Options()
        filename, _ = QFileDialog.getOpenFileName(self, "选择文件", "", "所有文件 (*);;文本文件 (*.txt)", options=options)
        if filename:
            self.file_label.setText(f'选择的文件: {filename}')
            self.file_path = filename

    def generate_keys_if_not_exists(self):
        """生成公钥和私钥，如果文件不存在"""
        if not os.path.exists('public.pem') or not os.path.exists('private.pem'):
            print("正在生成公钥和私钥...")
            self.generate_keys()
        else:
            print("公钥和私钥已存在。")

    def generate_keys(self):
        """生成公钥和私钥并保存为文件"""
        key = RSA.generate(2048)

        # 导出私钥
        private_key = key.export_key()
        with open('private.pem', 'wb') as f:
            f.write(private_key)
        print("私钥已保存为 'private.pem'")

        # 导出公钥
        public_key = key.publickey().export_key()
        with open('public.pem', 'wb') as f:
            f.write(public_key)
        print("公钥已保存为 'public.pem'")

    def load_public_key(self):
        # 从文件加载接收方公钥（用于加密会话密钥）
        with open('receiver_public.pem', 'rb') as f:
            public_key = RSA.import_key(f.read())
        return public_key

    def load_private_key(self):
        # 从文件加载私钥（用于签名文件）
        with open('private.pem', 'rb') as f:
            private_key = RSA.import_key(f.read())
        return private_key

    def encrypt_file(self, filename, public_key):
        # 为 AES 加密生成随机会话密钥
        session_key = get_random_bytes(16)

        # 选择加密模式
        mode = self.mode_combo.currentText()
        if mode == 'CBC':
            cipher_aes = AES.new(session_key, AES.MODE_CBC)
            iv = cipher_aes.iv  # 获取 CBC 模式使用的 IV
        elif mode == 'ECB':
            cipher_aes = AES.new(session_key, AES.MODE_ECB)
            iv = None

        # 加密文件
        with open(filename, 'rb') as f:
            plaintext = f.read()

        ciphertext = cipher_aes.encrypt(pad(plaintext, AES.block_size))  # 对明文进行填充，以满足块大小要求

        # 使用 RSA 加密会话密钥
        cipher_rsa = PKCS1_OAEP.new(public_key)
        encrypted_session_key = cipher_rsa.encrypt(session_key)

        return encrypted_session_key, iv, ciphertext

    def sign_file(self, filename, private_key):
        # 计算文件的 SHA-256 哈希值
        hash_obj = SHA256.new()
        with open(filename, 'rb') as f:
            while chunk := f.read(4096):
                hash_obj.update(chunk)

        # 使用私钥签名哈希值
        signer = pkcs1_15.new(private_key)
        signature = signer.sign(hash_obj)

        return signature

    def send_file(self):
        # 获取服务器地址和端口
        host = self.server_ip.text()
        port = int(self.server_port.text())

        # 加载公钥（用于加密会话密钥）
        public_key = self.load_public_key()

        # 加载私钥（用于签名文件）
        private_key = self.load_private_key()

        # 加密选择的文件
        encrypted_session_key, iv, ciphertext = self.encrypt_file(self.file_path, public_key)

        # 签名文件
        signature = self.sign_file(self.file_path, private_key)

        # 建立 socket 连接
        client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        client_socket.connect((host, port))

        # 发送加密的会话密钥、IV、密文和签名
        client_socket.sendall(encrypted_session_key)
        client_socket.sendall(iv)
        client_socket.sendall(ciphertext)
        client_socket.sendall(signature)

        client_socket.close()
        print("文件发送成功。")
        # 提示用户
        self.file_label.setText('文件发送成功！')


def main():
    app = QApplication(sys.argv)
    ex = FileTransferApp()
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()