[gentoo-user] strange error using courier-imapd-ssl

[gentoo-user] strange error using courier-imapd-ssl

[covici]

Hi.  Well, I use an emacs mua and I get my mail using
courier-imapd-ssl.  Now, every so often, the system tells me
auto-plugged off and gives me this line:

GnuTLS error: #<process IMAP>, -110

Now the real cause seems to be a problem with courier-imapd-ssl and
the status looks like this:

● courier-imapd-ssl.service - Courier IMAP Daemon
     Loaded: loaded (/usr/lib/systemd/system/courier-imapd-ssl.service; enabled; preset: disabled)
     Active: active (running) since Sat 2024-12-21 15:27:42 EST; 24h ago
 Invocation: b3752652fabd45d4b1967183e23d5e1a
    Process: 1981694 ExecStart=/usr/lib64/courier-imap/gentoo-imapd-ssl.rc (code=exited, status=0/SUCCESS)
   Main PID: 1981703 (couriertcpd)
      Tasks: 10 (limit: 38196)
     Memory: 15.8M
     CGroup: /system.slice/courier-imapd-ssl.service
             ├─1981703 /usr/lib64/courier-imap/couriertcpd -address=0 -stderrlogger=/usr/lib64/courier-imap/courierlogger -stderrloggername=imapd-ssl -maxprocs=40 -maxperip=4 -pid=/var/run/imapd-ssl.pid -nodnslookup 993 /usr/sbin/couriertls -server -tcpd /usr/sbin/imaplogin /usr/lib64/courier-imap/courier-imapd.indirect .maildir
             ├─1981705 /usr/lib64/courier-imap/courierlogger imapd-ssl
             ├─2118449 /usr/sbin/couriertls -server -tcpd /usr/sbin/imaplogin /usr/lib64/courier-imap/courier-imapd.indirect .maildir
             ├─2118450 /usr/sbin/couriertls -server -tcpd /usr/sbin/imaplogin /usr/lib64/courier-imap/courier-imapd.indirect .maildir
             ├─2118451 /usr/sbin/courier-imapd .maildir
             ├─2118452 /usr/sbin/courier-imapd .maildir
             ├─2128146 /usr/sbin/couriertls -server -tcpd /usr/sbin/imaplogin /usr/lib64/courier-imap/courier-imapd.indirect .maildir
             ├─2128147 /usr/sbin/courier-imapd .maildir
             ├─2128157 /usr/sbin/couriertls -server -tcpd /usr/sbin/imaplogin /usr/lib64/courier-imap/courier-imapd.indirect .maildir
             └─2128158 /usr/sbin/imaplogin /usr/lib64/courier-imap/courier-imapd.indirect .maildir

Dec 22 15:41:46 ccs.covici.com imapd-ssl[1981705]: Maximum connection limit reached for ::ffff:166.84.7.75
Dec 22 15:44:10 ccs.covici.com imapd-ssl[1981705]: ip=[::ffff:65.49.1.74], couriertls: accept: error:0A000126:SSL routines::unexpected eof while reading
Dec 22 15:44:25 ccs.covici.com imapd-ssl[1981705]: Connection, ip=[::ffff:65.49.1.72], port=[20427]
Dec 22 15:44:25 ccs.covici.com imapd-ssl[1981705]: ip=[::ffff:65.49.1.72], couriertls: read: error:0A000126:SSL routines::unexpected eof while reading
Dec 22 15:44:25 ccs.covici.com imapd-ssl[1981705]: Disconnected, ip=[::ffff:65.49.1.72], port=[20427], time=0, starttls=1
Dec 22 15:46:10 ccs.covici.com imapd-ssl[1981705]: Connection, ip=[::ffff:166.84.7.75], port=[64882]
Dec 22 15:46:10 ccs.covici.com imapd-ssl[1981705]: LOGIN FAILED, method=CRAM-MD5, ip=[::ffff:166.84.7.75], port=[64882]
Dec 22 15:46:15 ccs.covici.com imapd-ssl[1981705]: LOGIN, user=cell4612, ip=[::ffff:166.84.7.75], port=[64882], protocol=IMAP, starttls=1
Dec 22 15:46:16 ccs.covici.com imapd-ssl[1981705]: Connection, ip=[::ffff:166.84.7.75], port=[64885]
Dec 22 15:46:16 ccs.covici.com imapd-ssl[1981705]: LOGIN FAILED, method=CRAM-MD5, ip=[::ffff:166.84.7.75], port=[64885]

I can always get back to normal by restarting courier-imapd-ssl, but I
would like not to have to do this -- it happens every day or two.

Any ideas?

Thanks in advance for any suggestions.

Re: [gentoo-user] strange error using courier-imapd-ssl

[Matt Jolly]

Hi,

It's been a while since I dealt with IMAP, but the SSL errors
that you're listing here are from the client side.

On 23/12/24 07:02, covici@ccs.covici.com wrote:
 > Dec 22 15:44:10 ccs.covici.com imapd-ssl[1981705]: 
ip=[::ffff:65.49.1.74], couriertls: accept: error:0A000126:SSL 
routines::unexpected eof while reading
 > Dec 22 15:44:25 ccs.covici.com imapd-ssl[1981705]: Connection, 
ip=[::ffff:65.49.1.72], port=[20427]
 > Dec 22 15:44:25 ccs.covici.com imapd-ssl[1981705]: 
ip=[::ffff:65.49.1.72], couriertls: read: error:0A000126:SSL 
routines::unexpected eof while reading

This is happening because your client is not cleanly closing the
connection[1].

In OpenSSL you can set the `SSL_OP_IGNORE_UNEXPECTED_EOF` option
to pretend that the client cleanly closed the connection. See:

https://www.openssl.org/docs/man3.1/man3/SSL_set_options.html

Cheers,

Matt

1: https://github.com/openssl/openssl/discussions/22690