如何使用squirrelmail连接993端口上的dovecot

我试图连接993端口上的dovecot，但dovecot显示以下错误

dovecot: imap-login: Disconnected (no auth attempts in 60 secs): user=<>, rip=192.***.***.***, lip=192.***.***.***, TLS handshaking: SSL_accept() failed: error:140760FC:SSL routines:SSL23_GET_CLIENT_HELLO:unknown protocol, session=<3k6jgTwVLwDAqL+E>

当我尝试在squirrelmail服务器上使用telnet和openssl时

[root@aa ~]# telnet dovecot.server 993
Trying 192.***.***.***...
Connected to dovecot.server.
Escape character is '^]'.

[root@aa ~]# openssl s_client -connect dovecot.server:993
...
...
* OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE AUTH=PLAIN AUTH=LOGIN] Dovecot ready.

---

注意：143端口工作正常。

检查PHP错误日志，了解以下内容：

PHP Warning:  fsockopen(): SSL operation failed with code 1. OpenSSL Error messages: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed ..
PHP Warning:  fsockopen(): Failed to enable crypto ..
PHP Warning:  fsockopen(): unable to connect to tls://dovecot.server:993 (Unknown error) ..

如果是这种情况，openssl库将无法验证服务器的证书。通过将连接证书添加到本地证书库，可以轻松修复此问题。您可以使用

将它添加到证书文件中，您就可以开始了

一个警告：证书CN必须与用于连接到服务器的主机名匹配！如果它是自签名的，请确保它使用
dovecot.server
作为CN

PHP Warning:  fsockopen(): SSL operation failed with code 1. OpenSSL Error messages: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed ..
PHP Warning:  fsockopen(): Failed to enable crypto ..
PHP Warning:  fsockopen(): unable to connect to tls://dovecot.server:993 (Unknown error) ..

openssl x509 -in <(openssl s_client -connect dovecot.server:993 -prexit 2>/dev/null) > /tmp/cacert.pem