请求ca key：openssl genrsa -out ca.key 1024
建立ca 证书：openssl req -new -x509 -days 3650 -key ca.key -out ca.crt -subj "/C=CN/ST=Shanghai/L=Shanghai/O=ule/OU=ule.com Root CA"
请求服务器私钥：openssl genrsa -out server.key 1024
生成服务器证书：openssl req -new -x509 -days 3650 -key server.key -out server.csr -subj "/C=CN/ST=Shanghai/L=Shanghai/O=ule/OU=ule.com/CN=ule.com"
自建ca证书签名服务器证书：openssl ca -in server.csr -out server.crt -cert ca.crt -keyfile ca.key
生成cer后缀ca文件：openssl x509 -inform der -in ca.cer -out ca.crt
生成der后缀ca文件：openssl x509 -outform der -in ca.crt -out ca.der
生成der后缀服务器文件：openssl x509 -outform der -in server.crt -out server.der
生成cer后缀服务器文件：openssl x509 -outform der -in server.crt -out server.cer
生成p12后缀服务器文件：openssl pkcs12 -export -clcerts -in server.crt -inkey ca.key -out server.p12
