我一直在努力寻找快递员imap的默认TLS_CIPHER_LIST，当imapd-ssl中没有定义该设置时，我想知道该如何设置。
谢谢你
该 快递文件 描述了 "TLS_CIPHER_LIST"，但没有提到默认值。看了一下源代码，发现当前的默认值是 TLSv1:HIGH:!LOW:!MEDIUM:!EXP:!NULL:!aNULL@STRENGTH. 如果您的Courier版本是针对OpenSSL构建的（与DebianUbuntu的软件包相反，您可以使用OpenSSL。构建的 针对GnuTLS)，你可以通过运行以下命令将其扩展为完整的密码名称列表。
$ openssl ciphers 'TLSv1:HIGH:!LOW:!MEDIUM:!EXP:!NULL:!aNULL@STRENGTH'
在Ubuntu 20.04机器上运行OpenSSL 1.1.1f的输出示例。
TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:ECDHE-PSK-AES256-CBC-SHA384:ECDHE-PSK-AES256-CBC-SHA:RSA-PSK-AES256-CBC-SHA384:DHE-PSK-AES256-CBC-SHA384:ECDHE-PSK-CAMELLIA256-SHA384:RSA-PSK-CAMELLIA256-SHA384:DHE-PSK-CAMELLIA256-SHA384:PSK-AES256-CBC-SHA384:PSK-CAMELLIA256-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-DSS-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES256-CCM8:ECDHE-ECDSA-AES256-CCM:DHE-RSA-AES256-CCM8:DHE-RSA-AES256-CCM:ECDHE-ECDSA-ARIA256-GCM-SHA384:ECDHE-ARIA256-GCM-SHA384:DHE-DSS-ARIA256-GCM-SHA384:DHE-RSA-ARIA256-GCM-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA256:ECDHE-ECDSA-CAMELLIA256-SHA384:ECDHE-RSA-CAMELLIA256-SHA384:DHE-RSA-CAMELLIA256-SHA256:DHE-DSS-CAMELLIA256-SHA256:DHE-RSA-AES256-SHA:DHE-DSS-AES256-SHA:DHE-RSA-CAMELLIA256-SHA:DHE-DSS-CAMELLIA256-SHA:RSA-PSK-AES256-GCM-SHA384:DHE-PSK-AES256-GCM-SHA384:RSA-PSK-CHACHA20-POLY1305:DHE-PSK-CHACHA20-POLY1305:ECDHE-PSK-CHACHA20-POLY1305:DHE-PSK-AES256-CCM8:DHE-PSK-AES256-CCM:RSA-PSK-ARIA256-GCM-SHA384:DHE-PSK-ARIA256-GCM-SHA384:AES256-GCM-SHA384:AES256-CCM8:AES256-CCM:ARIA256-GCM-SHA384:PSK-AES256-GCM-SHA384:PSK-CHACHA20-POLY1305:PSK-AES256-CCM8:PSK-AES256-CCM:PSK-ARIA256-GCM-SHA384:AES256-SHA256:CAMELLIA256-SHA256:SRP-DSS-AES-256-CBC-SHA:SRP-RSA-AES-256-CBC-SHA:SRP-AES-256-CBC-SHA:RSA-PSK-AES256-CBC-SHA:DHE-PSK-AES256-CBC-SHA:AES256-SHA:CAMELLIA256-SHA:PSK-AES256-CBC-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES128-SHA:ECDHE-PSK-AES128-CBC-SHA256:ECDHE-PSK-AES128-CBC-SHA:RSA-PSK-AES128-CBC-SHA256:DHE-PSK-AES128-CBC-SHA256:ECDHE-PSK-CAMELLIA128-SHA256:RSA-PSK-CAMELLIA128-SHA256:DHE-PSK-CAMELLIA128-SHA256:PSK-AES128-CBC-SHA256:PSK-CAMELLIA128-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-CCM8:ECDHE-ECDSA-AES128-CCM:DHE-RSA-AES128-CCM8:DHE-RSA-AES128-CCM:ECDHE-ECDSA-ARIA128-GCM-SHA256:ECDHE-ARIA128-GCM-SHA256:DHE-DSS-ARIA128-GCM-SHA256:DHE-RSA-ARIA128-GCM-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA256:DHE-DSS-AES128-SHA256:ECDHE-ECDSA-CAMELLIA128-SHA256:ECDHE-RSA-CAMELLIA128-SHA256:DHE-RSA-CAMELLIA128-SHA256:DHE-DSS-CAMELLIA128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA:DHE-RSA-CAMELLIA128-SHA:DHE-DSS-CAMELLIA128-SHA:RSA-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-CCM8:DHE-PSK-AES128-CCM:RSA-PSK-ARIA128-GCM-SHA256:DHE-PSK-ARIA128-GCM-SHA256:AES128-GCM-SHA256:AES128-CCM8:AES128-CCM:ARIA128-GCM-SHA256:PSK-AES128-GCM-SHA256:PSK-AES128-CCM8:PSK-AES128-CCM:PSK-ARIA128-GCM-SHA256:AES128-SHA256:CAMELLIA128-SHA256:SRP-DSS-AES-128-CBC-SHA:SRP-RSA-AES-128-CBC-SHA:SRP-AES-128-CBC-SHA:RSA-PSK-AES128-CBC-SHA:DHE-PSK-AES128-CBC-SHA:AES128-SHA:CAMELLIA128-SHA:PSK-AES128-CBC-SHA
请注意 这个列表取决于你的OpenSSL版本 所以请确保你在你的邮件服务器机器上运行这个命令。仔细阅读这个列表是个好主意。即使在我最新的系统上，这个列表也包含了不少必须被认为是弱的密码。
https:/www.courier-mta.orgcouriertls.html sais.TLS_CIPHER_LIST=cipherlist
TLS_CIPHER_LIST=密码列表
- 可选择设置要使用的协议密码列表。更多信息请参见OpenSSL的文档。
所以我认为它采用的是openssl中定义的密码。
注意：除了Ciphers列表之外，你可能还想设置
TLS_PROTOCOL="TLSv1.2"
这将关闭TLS1.0和TLS1.1。
TLSv1.2是否工作取决于你的openssl库是否足够新，以支持TLS1.2。
如果你想在你的SSL证书中禁用TLS v1.0和TLS v1.1，你必须在你的浏览器中进行设置，如 nginx，请看这个链接。https:/libre-software.nettls-nginx#tls。