iOS配置原生推送消息后，需要验证创建的pem文件是否有效，使用以下指令即可验证
openssl s_client -connect gateway.sandbox.push.apple.com:2195 -cert cert.pem -key cert-key.pem
以上是开发环境使用的配置，生产环境对于的host如下
开发环境：gateway.sandbox.push.apple.com:2195
生产环境：gateway.push.apple.com:2195
连通成功后，有以下提示
......
SSL handshake has read 4468 bytes and written 2608 bytes
---
New, TLSv1/SSLv3, Cipher is DES-CBC3-SHA
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
SSL-Session:
Protocol : TLSv1.2
Cipher : DES-CBC3-SHA
Session-ID:
Session-ID-ctx:
Master-Key: 73B04430C212A3DE4EE5677290BE8765BD54C3F210ABCB5C5555E6A6ECEA567576E896B3F5EFE0BE2B18EB
Start Time: 1683185953
Timeout : 7200 (sec)
Verify return code: 0 (ok)
---
closed
