# PBKDF2算法伪代码
def pbkdf2_hash(password, salt, iterations=10000):
    return pbkdf2(password, salt, iterations, 32, 'sha512')

# TPM密钥封装伪代码
def tpm_seal_password_key(password_hash, pcr_values):
    """
    将密码哈希密钥封装到TPM中
    只有在特定PCR状态下才能解封
    """
    sealed_key = tpm2_create_sealed_object(
        parent_handle=SRK_HANDLE,
        data=password_hash,
        auth_policy=pcr_policy(pcr_values)
    )
    return sealed_key

# SHA-512计算特点
- 计算速度极快（每秒数十亿次）
- 内存占用极少（几KB）
- 易于并行计算
- 专用硬件加速（GPU、ASIC）

# Argon2算法参数
def argon2_hash(password, salt, 
                time_cost=3,      # 时间成本（迭代次数）
                memory_cost=65536, # 内存成本（KB）
                parallelism=4,    # 并行度
                hash_length=32):  # 输出长度
    return argon2.hash(password, salt, time_cost, memory_cost, parallelism, hash_length)

# Argon2内存使用模式
def argon2_memory_pattern():
    """
    Argon2需要大量内存来存储中间状态
    攻击者必须为每个密码尝试分配相同的内存
    """
    memory_blocks = allocate_memory(memory_cost * 1024)  # 分配大量内存
    
    # 在内存中进行复杂的数据依赖操作
    for i in range(time_cost):
        for j in range(memory_cost):
            memory_blocks[j] = complex_operation(
                memory_blocks[j], 
                memory_blocks[pseudo_random_index(j)]
            )
    
    return final_hash(memory_blocks)

# 时间成本可调节
def compare_time_costs():
    """
    比较不同时间成本的计算时间
    """
    passwords = ["password123", "admin", "123456"]
    
    # SHA-512：固定时间，极快
    for pwd in passwords:
        start = time.time()
        sha512_hash = hashlib.sha512(pwd.encode()).hexdigest()
        print(f"SHA-512: {time.time() - start:.6f}s")
    
    # Argon2：可调节时间成本
    for time_cost in [1, 3, 10]:
        start = time.time()
        argon2_hash = argon2.hash_password_raw(
            pwd.encode(), 
            salt=b"somesalt", 
            time_cost=time_cost,
            memory_cost=65536,
            parallelism=1
        )
        print(f"Argon2 (t={time_cost}): {time.time() - start:.6f}s")

# 破解成本估算
def crack_cost_analysis():
    """
    估算不同算法的破解成本
    """
    
    # SHA-512 + Salt破解成本
    sha512_cost = {
        "gpu_per_second": 10**9,  # 10亿次/秒
        "hardware_cost": 1000,    # GPU价格
        "power_cost": 0.1,        # 电力成本
        "time_to_crack_8char": "几小时",
        "time_to_crack_12char": "几年"
    }
    
    # Argon2破解成本
    argon2_cost = {
        "memory_per_attempt": 64,  # 64MB内存
        "attempts_per_second": 10, # 受内存限制
        "hardware_cost": 50000,    # 需要大量内存
        "power_cost": 10,          # 高内存功耗
        "time_to_crack_8char": "几年",
        "time_to_crack_12char": "几千年"
    }
    
    return sha512_cost, argon2_cost

# 不同应用场景的Argon2参数建议
def argon2_parameters_recommendation():
    """
    根据安全需求推荐Argon2参数
    """
    scenarios = {
        "高安全系统": {
            "time_cost": 10,
            "memory_cost": 1024*1024,  # 1GB
            "parallelism": 4,
            "description": "适用于高价值系统，可容忍较长登录时间"
        },
        "企业应用": {
            "time_cost": 3,
            "memory_cost": 65536,      # 64MB
            "parallelism": 4,
            "description": "平衡安全性和用户体验"
        },
        "移动应用": {
            "time_cost": 2,
            "memory_cost": 32768,      # 32MB
            "parallelism": 2,
            "description": "考虑移动设备资源限制"
        }
    }
    return scenarios

def tpm_sealed_key_protection():
    """
    TPM密钥封装防护机制
    """
    # 1. 系统启动时度量关键组件
    boot_measurements = measure_boot_components()
    
    # 2. 将度量值存储到PCR寄存器
    extend_pcr(boot_measurements)
    
    # 3. 密钥封装时绑定到特定PCR状态
    sealed_key = tpm_seal(
        data=disk_encryption_key,
        pcr_selection=[0, 1, 2, 3, 4, 5, 6, 7]  # 绑定到多个PCR
    )
    
    # 4. 只有在相同PCR状态下才能解封
    if current_pcr_values == sealed_pcr_values:
        disk_key = tpm_unseal(sealed_key)
        return disk_key
    else:
        raise SecurityError("系统完整性验证失败")

def advanced_key_derivation():
    """
    结合多种因素的密钥派生
    """
    # 1. 用户密码
    user_password = input("请输入密码: ")
    
    # 2. TPM密钥
    tpm_key = tpm_get_random(32)
    
    # 3. 硬件指纹
    hardware_fingerprint = get_hardware_id()
    
    # 4. 时间因子（可选）
    time_factor = int(time.time() / 3600)  # 小时级别
    
    # 5. 组合所有因子
    combined_input = (
        user_password.encode() + 
        tpm_key + 
        hardware_fingerprint + 
        time_factor.to_bytes(8, 'big')
    )
    
    # 6. 使用Argon2派生最终密钥
    final_key = argon2.hash_password_raw(
        combined_input,
        salt=b"system_salt",
        time_cost=3,
        memory_cost=65536,
        parallelism=4
    )
    
    return final_key

def remote_attestation():
    """
    远程认证确保系统完整性
    """
    # 1. 获取当前PCR值
    current_pcrs = tpm_read_pcrs()
    
    # 2. 生成认证报告
    attestation_report = tpm_quote(
        pcr_selection=list(range(24)),
        nonce=server_nonce
    )
    
    # 3. 发送到远程服务器验证
    response = requests.post(
        "https://attestation-server.com/verify",
        json={
            "pcr_values": current_pcrs,
            "quote": attestation_report,
            "certificate_chain": tpm_cert_chain
        }
    )
    
    # 4. 根据验证结果决定是否授权
    if response.json()["trusted"]:
        return grant_access()
    else:
        return deny_access("系统完整性验证失败")