Python中网络安全的常见问题及解决策略

import MySQLdb

def login(username, password):
    conn = MySQLdb.connect(host='localhost', user='root', passwd='password', db='mydb')
    cursor = conn.cursor()

    # 使用?占位符替代用户输入的参数
    cursor.execute("SELECT * FROM users WHERE username = ? AND password = ?", (username, password))
    result = cursor.fetchone()

    cursor.close()
    conn.close()

    if result:
        return True
    else:
        return False

from flask import Flask, request, escape

app = Flask(__name__)

@app.route('/search')
def search():
    keyword = request.args.get('keyword')
    # 使用escape函数对用户输入进行转义
    keyword = escape(keyword)
    # 对转义后的关键词进行进一步处理
    # ...
    return "Search results"

if __name__ == '__main__':
    app.run()

from flask import Flask, request, session
import hashlib
import random

app = Flask(__name__)

@app.route('/transfer', methods=['POST'])
def transfer():
    csrf_token = request.form.get('csrf_token')
    # 验证Token的合法性
    if csrf_token == session.get('csrf_token'):
        # 转账操作
        amount = request.form.get('amount')
        # ...
        return 'Transfer successful'
    else:
        return 'Invalid request'

@app.route('/transfer_form')
def transfer_form():
    # 生成和存储Token
    csrf_token = hashlib.sha256(str(random.getrandbits(256)).encode()).hexdigest()
    session['csrf_token'] = csrf_token
    return f"""
    <form action="/transfer" method="POST">
        <input type="hidden" name="csrf_token" value="{csrf_token}">
        <input type="text" name="amount">
        <input type="submit" value="Transfer">
    </form>
    """

if __name__ == '__main__':
    app.secret_key = 'secret'
    app.run()