使用openssl生成ssl（https）证书

openssl生成证书

[nginx@machina key]$ pwd
/app/nginx/key

1. 生成私钥
   openssl genrsa -out server.key 2048
2. 生成证书请求
   openssl req -new -key server.key -out server.csr
3. 填入信息

   
   [nginx@machina key]$ openssl req -new -key server.key -out server.csr
   You are about to be asked to enter information that will be incorporated
   into your certificate request.
   What you are about to enter is what is called a Distinguished Name or a DN.
   There are quite a few fields but you can leave some blank
   For some fields there will be a default value,
   If you enter '.', the field will be left blank.
   -----
   Country Name (2 letter code) [XX]:cn
   State or Province Name (full name) []:gd
   Locality Name (eg, city) [Default City]:gz
   Organization Name (eg, company) [Default Company Ltd]:ai
   Organizational Unit Name (eg, section) []:ai
   Common Name (eg, your name or your server's hostname) []:112.96.28.206
   Email Address []:

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:
[nginx@machina key]$
[nginx@machina key]$ ls
old server.csr server.key

4. 备份一份服务器密钥文件
cp server.key server.key.org
5. 去除文件口令
openssl rsa -in server.key.org -out server.key
6. 生成证书文件server.crt
openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt

[nginx@machina key]$ openssl rsa -in server.key.org -out server.key
writing RSA key
[nginx@machina key]$
[nginx@machina key]$ openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt
Signature ok
subject=/C=cn/ST=gd/L=gz/O=ai/OU=ai/CN=112.96.28.206
Getting Private key

一般只需三步：
1. openssl genrsa -out server.key 2048
2. openssl req -new -key server.key -out server.csr
3. openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt

关于密码：
openssl genrsa -out server.key 2048
    不需要密码。
openssl genrsa -des3 -out server.key 2048
    需要密码。
https://www.jianshu.com/p/9523d888cf77

关于域名：
用openssl，域名可以不输；
用keystore，必须输入。