X509是系列的函数在我们开发与PKI相关的应用的时候我们都会用到，但是OpenSSL中对X509的描述并不是很多，鉴于些，我将以前工作与学习过程的经验整理出来，供大家参考，不用多走弯路，可以将精力集中在自己要处理的业务逻辑上，同时也希望更多的人参与到研究与整理信息安全的理论与技术中来，提高中国的科研与应用技术水平。-X509 is a series of functions in our development and PKI-related applications when we will be used, but the descr iption of OpenSSL X509 is not a lot, in view of some, I will work with previous experience in the learning process of sorting out, for your reference, needless detours, you can concentrate on the business logic to handle on their own, but also want more people to participate in research and organize information security theory and technology in an effort to improve China s scientific research and application of technology.