56 lines
1.8 KiB
Python
56 lines
1.8 KiB
Python
|
import os
|
|||
|
|
import base64
|
|||
|
|
from Crypto.Cipher import AES
|
|||
|
|
from Crypto.Util.Padding import pad, unpad
|
|||
|
|
from fastapi import HTTPException
|
|||
|
|
|
|||
|
|
# 硬编码AES密钥（32字节、AES-256）
|
|||
|
|
AES_SECRET_KEY = b"jr1vA6tfWMHOYi6UXw67UuO6fdak2rMa"
|
|||
|
|
AES_BLOCK_SIZE = 16 # AES固定块大小
|
|||
|
|
|
|||
|
|
# 校验密钥长度
|
|||
|
|
valid_key_lengths = [16, 24, 32]
|
|||
|
|
if len(AES_SECRET_KEY) not in valid_key_lengths:
|
|||
|
|
raise ValueError(
|
|||
|
|
f"AES密钥长度必须为{valid_key_lengths}字节、当前为{len(AES_SECRET_KEY)}字节"
|
|||
|
|
)
|
|||
|
|
|
|||
|
|
|
|||
|
|
def aes_encrypt(plaintext: str) -> dict:
|
|||
|
|
"""AES-CBC模式加密（返回密文+IV、均为Base64编码）"""
|
|||
|
|
try:
|
|||
|
|
# 生成随机IV（16字节）
|
|||
|
|
iv = os.urandom(AES_BLOCK_SIZE)
|
|||
|
|
|
|||
|
|
# 创建加密器
|
|||
|
|
cipher = AES.new(AES_SECRET_KEY, AES.MODE_CBC, iv)
|
|||
|
|
|
|||
|
|
# 明文填充并加密
|
|||
|
|
padded_plaintext = pad(plaintext.encode("utf-8"), AES_BLOCK_SIZE)
|
|||
|
|
ciphertext = base64.b64encode(cipher.encrypt(padded_plaintext)).decode("utf-8")
|
|||
|
|
iv_base64 = base64.b64encode(iv).decode("utf-8")
|
|||
|
|
|
|||
|
|
return {
|
|||
|
|
"ciphertext": ciphertext,
|
|||
|
|
"iv": iv_base64,
|
|||
|
|
"algorithm": "AES-CBC"
|
|||
|
|
}
|
|||
|
|
except Exception as e:
|
|||
|
|
raise HTTPException(status_code=500, detail=f"AES加密失败：{str(e)}") from e
|
|||
|
|
|
|||
|
|
|
|||
|
|
def aes_decrypt(ciphertext: str, iv: str) -> str:
|
|||
|
|
"""AES-CBC模式解密"""
|
|||
|
|
try:
|
|||
|
|
# 解码Base64
|
|||
|
|
ciphertext_bytes = base64.b64decode(ciphertext)
|
|||
|
|
iv_bytes = base64.b64decode(iv)
|
|||
|
|
|
|||
|
|
# 创建解密器
|
|||
|
|
cipher = AES.new(AES_SECRET_KEY, AES.MODE_CBC, iv_bytes)
|
|||
|
|
|
|||
|
|
# 解密并去填充
|
|||
|
|
decrypted_bytes = unpad(cipher.decrypt(ciphertext_bytes), AES_BLOCK_SIZE)
|
|||
|
|
return decrypted_bytes.decode("utf-8")
|
|||
|
|
except Exception as e:
|
|||
|
|
raise HTTPException(status_code=500, detail=f"AES解密失败：{str(e)}") from e
|