说明：  openssl是一个功能丰富且自包含的开源安全工具箱。它提供的主要功能有：SSL协议实现(包括SSLv2、SSLv3和TLSv1)、大量软算法(对称/非对称/摘要)、大数运算、非对称算法密钥生成、ASN.1编解码库、证书请求(PKCS10)编解码、数字证书编解码、CRL编解码、OCSP协议、数字证书验证、PKCS7标准实现和PKCS12个人数字证书格式实现等功能。
(openssl is a feature-rich, self-contained open-source security toolkit. It provides the main functions are: SSL protocol implementation (including SSLv2, SSLv3 and TLSv1), a large number of software algorithms (symmetric/asymmetric/summary), large numbers operation, asymmetric key generation algorithm, ASN.1 decoding library, certificate request (PKCS10) decoding, encoding and decoding digital certificates, CRL codec, OCSP protocol, digital certificate authentication, PKCS7 and PKCS12 standard to achieve personal digital certificate formats, and so on.)