1、生成ca key
openssl genrsa -out ca.key 2048
2、生成ca证书
openssl req -x509 -new -key ca.key -out ca.pem

3、生成服务器key
openssl genrsa -out sever.key 2048
4、生成证书请求
openssl req -new -key sever.key -out server.csr

5、生成证书
openssl x509 -req -days 365 -in server.csr -CA ca.pem -CAkey ca.key -CAcreateserial -out server.crt