如何使用.pem文件中提供的公钥验证签名？

pip install cryptography

from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import padding
from cryptography.hazmat.backends import default_backend

with open("path/to/your/public_key.pem", "rb") as key_file:
    public_key = serialization.load_pem_public_key(
        key_file.read(),
        backend=default_backend()
    )

signature = ... # 将签名存储在这个变量中
message = ... # 将原始消息存储在这个变量中

try:
    public_key.verify(
        signature,
        message,
        padding.PSS(
            mgf=padding.MGF1(hashes.SHA256()),
            salt_length=padding.PSS.MAX_LENGTH
        ),
        hashes.SHA256()
    )
    print("签名验证成功")
except Exception as e:
    print("签名验证失败:", e)