python 读取域名信息

#!/usr/bin/env python
# _*_coding:utf-8_*_
import OpenSSL
from OpenSSL import crypto
from dateutil import parser

def get_cert_detail(cert_file):
    """
    获取证书信息
    :param cert_file:
    :return:
    """
    cert = crypto.load_certificate(crypto.FILETYPE_PEM, open(cert_file).read())
    subject = cert.get_subject()
    issuer = cert.get_issuer()
    datetime_struct_before = parser.parse(cert.get_notBefore().decode("UTF-8"))
    datetime_struct_after = parser.parse(cert.get_notAfter().decode("UTF-8"))
    extensions_domain_list = []
    for i in cert.to_cryptography().extensions:
        if i.oid.dotted_string == "2.5.29.17":
            extensions_domain_list = [i.value for i in i.value]
    return {
        # 证书版本
        "version": cert.get_version() + 1,
        # 证书序列号
        "serial_number": hex(cert.get_serial_number()),
        # 证书中使用的签名算法
        "signature": cert.get_signature_algorithm().decode("UTF-8"),
        # 颁发者
        "common_name": issuer.commonName,
        # 有效期开始
        "before_datetime": datetime_struct_before.strftime('%Y-%m-%d %H:%M:%S'),
        # 有效期结束
        "after_datetime": datetime_struct_after.strftime('%Y-%m-%d %H:%M:%S'),
        # 证书是否过期
        "is_expired": bool(1 - cert.has_expired()),
        # 公钥长度
        "pubkey_count": cert.get_pubkey().bits(),
        # 可以使用的域名列表
        "extensions_domains": extensions_domain_list
    }