问题描述
我有一个用于在数据库中存储证书的.NET应用程序的用例。其中一个要求是应用程序拒绝包含私钥的证书。用户将上传证书文件（特别是.CER或.CRT），应用程序将它作为X509Certificate2对象导入，以便我可以检查HasPrivakeKey属性。
I have a use case for a .NET application that stores certificates in a database. One of the requirements is for the application to reject certificates that contain private keys. The user will upload a certificate file (specifically .CER or .CRT) and the application will import it as an X509Certificate2 object so that I can check the HasPrivakeKey property.
I知道.PFX文件可以包含私钥，但是.CER或.CRT文件也可能包含私钥？如果是这样，我如何生成测试证书以测试应用程序逻辑？
I know that .PFX files can contain private keys, but is it possible for .CER or .CRT files to also contain private keys? If so, how can I generate a test certificate in order to test the application logic?
推荐答案
PEM格式与私钥。但是如果呈现这种格式，则定义以下结果：
First, .NET do not support PEM format with private key. But if such format is presented the following outcome is defined:
1）如果证书头/页脚是文件中的第一个，.NET将忽略文件的其余内容（例如私钥信息）并创建有效的 X509Certificate2 对象而不使用私钥（因为CryptoAPI函数不支持PKCS＃1和PKCS＃8它们由 X509Certificate2 构造函数调用。虽然，有一些函数可以使用PKCS＃1）。
1) if certificate header/footer is first in the file, .NET will ignore the rest content of the file (e.g. private key information) and creates valid X509Certificate2 object without private key (because PKCS#1 and PKCS#8 keys are not supported by CryptoAPI functions which are called by a X509Certificate2 constructor. Though, there are functions to work with PKCS#1).
2 ）如果私钥头/页脚是文件中的第一个，.NET将引发有关无效证书的异常。
2) if private key header/footer is first in the file, .NET will raise exception about invalid certificate.
ps此组合仅在使用Base64编码时可用，并且每个部分使用页眉和页脚（例如 ----- BEGIN CERTIFICATE ----- 和 ----- END CERTIFICATE ----- ）。不能使用PKCS＃12容器以二进制形式组合它们。
p.s. this combination is possible only when Base64 encoding is used and each section uses header and footer (e.g. -----BEGIN CERTIFICATE----- and -----END CERTIFICATE-----). It is impossible to combine them in binary form without using PKCS#12 container.
更新：如果要测试自己，这里是这样的PEM文件的例子：
update: if you want to test it yourself, here is an example of such PEM file:
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----
X509Certificate2 此文件中的对象，调用将成功。交换部分，您将看到有关无效格式的异常。
when you instantiate an X509Certificate2 object from this file, the call will succeed. Swap sections and you will see exception about invalid format.
这篇关于是否可以将私钥包含在.CER证书文件中？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！