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I've been following this guide to set up a mail server on my server: http://flurdy.com/docs/postfix/edition5.html The only difference is that this tutorial uses a MySQL database and I've used PostgreSQL.

But I can't login to RoundCube. This is a message I get in the RoundCube error log:

[31-Dec-2013 16:40:42 +0100]: IMAP Error: Login failed for [email protected] from A.B.C.D. AUTHENTICATE CRAM-MD5: A0001 NO Login failed. in /usr/share/roundcube/program/lib/Roundcube/rcube_imap.php on line 184 (POST /?_task=login&_action=login)

This is from the IMAP log:

[31-Dec-2013 16:40:37 +0100]: [CB8A] S: * OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA AUTH=CRAM-MD5 AUTH=CRAM-SHA1 IDLE AUTH=PLAIN ACL ACL2=UNION] Courier-IMAP ready. Copyright 1998-2011 Double Precision, Inc.  See COPYING for distribution information.
[31-Dec-2013 16:40:37 +0100]: [CB8A] C: A0001 AUTHENTICATE CRAM-MD5
[31-Dec-2013 16:40:37 +0100]: [CB8A] S: + PDIxNUFCQjFGRjJBNTi1RUJEMTIzMjFEMDAwNDIxMTUzQGxpbm9kZT4=
[31-Dec-2013 16:40:37 +0100]: [CB8A] C: bWFya29Adm9kYW5vdmljLm5ldCBmMzk2njk0OTRiMTA1Mjc2YjllYWIxODhhZDI2OWM3NA==
[31-Dec-2013 16:40:42 +0100]: [CB8A] S: A0001 NO Login failed.

I have one user in my DB table in Postgres. Here he is:

<?xml version="1.0" encoding="utf-8" ?>
<data>
    <header>
        <column name="id" type="varchar" />
        <column name="name" type="varchar" />
        <column name="uid" type="int4" />
        <column name="gid" type="int4" />
        <column name="home" type="varchar" />
        <column name="maildir" type="varchar" />
        <column name="enabled" type="bool" />
        <column name="change_password" type="bool" />
        <column name="clear" type="varchar" />
        <column name="crypt" type="varchar" />
        <column name="quota" type="varchar" />
        <column name="procmailrc" type="varchar" />
        <column name="spamassassinrc" type="varchar" />
    </header>
    <records>
        <row>
            <column name="id">[email protected]</column>
            <column name="name">test</column>
            <column name="uid">5000</column>
            <column name="gid">5000</column>
            <column name="home">/var/spool/mail/virtual</column>
            <column name="maildir">test/</column>
            <column name="enabled">t</column>
            <column name="change_password">t</column>
            <column name="clear">aaaa</column>
            <column name="crypt">$5$c74a6630fAb058a5$Zo95c7qWT.o/Twg4niR/gcNoVq2XVVPl0aw6DoS8ufA</column>
            <column name="quota"></column>
            <column name="procmailrc"></column>
            <column name="spamassassinrc"></column>
        </row>
    </records>
</data>

I've tried logging in with both test and [email protected] and with both the plain aaaa password and the encrypted one. Just to be safe, I've also generated the password inside MySQL (using the expression from the guide) and then copied the result in the field in Postgres. And yes, MySQL and Postgres are on the same server. Here is the expression I used in MySQL:

select encrypt('password', CONCAT('$5$', MD5(RAND())));

I really don't know what else to do so any help would be appreciated. If you need more info, just say so.

EDIT:

I've managed to login to the server via telnet (when I fixed the missing mail directory problem). But I still can't connect with RoundCube. Here is the output from mail.log:

Dec 31 20:14:45 localhost imapd-ssl: Connection, ip=[::ffff:127.0.0.1]
Dec 31 20:14:45 localhost authdaemond: received auth request, service=imap, authtype=cram-md5
Dec 31 20:14:45 localhost authdaemond: authpgsql: trying this module
Dec 31 20:14:45 localhost authdaemond: cram: challenge=PDk1N0QxRTI3QTlFREy3MkYwODI3RUE2MDVDREREMTdBQGxpbm9kZT4=, response=bWFya28gY2Q5OTRmNDI2ZtY3NDUzZGM2YmJlYjhmNTI0ZWQ3NWI=
Dec 31 20:14:45 localhost authdaemond: cram: decoded challenge/response, username 'test'
Dec 31 20:14:45 localhost authdaemond: Install of a character set for Postgresql: UTF8
Dec 31 20:14:45 localhost authdaemond: SQL query: SELECT id, crypt, '', uid, gid, home, concat(home,'/',maildir), '', name, '' FROM users WHERE id = '[email protected]'  AND (enabled=TRUE)
Dec 31 20:14:45 localhost authdaemond: authpgsql: REJECT - try next module
Dec 31 20:14:45 localhost authdaemond: FAIL, all modules rejected
Dec 31 20:14:45 localhost imapd-ssl: LOGIN FAILED, method=CRAM-MD5, ip=[::ffff:127.0.0.1]
Dec 31 20:14:50 localhost imapd-ssl: Disconnected, ip=[::ffff:127.0.0.1], time=5, starttls=1
2
  • Try removing $5$ from your password field, it might be auto-detected. Dec 31, 2013 at 16:08
  • Tried it just now, both by just removing $5$ from the field and by recreating the password in MySQL without concat and $5$, but the result is the same. :/ I'd also like to point out that when I try to encrypt the password without the $5$ prefix, the resulting cipher is much shorter. So I'm guessing it doesn't use SHA256 by default.
    – morgoth84
    Dec 31, 2013 at 16:22

3 Answers 3

3

Being confronted with the very same issue, I did a few ours of Google-Foo to get to the root of the issue: As Gabriel assumed correcty in his answer, it's not the fault of Roundcube – but of the way the password is stored and the encryption works.

Few obvious basics

When talking about CRAM-MD5, MD5, or CRYPT, we're talking about one-way-encryption: A hash is generated. We cannot do that the other way around, deriving the clear-text password from the hash is (apart from brute-forcing) impossible and not realistic for any login-procedure. So with the password stored using one of these hashes, we can only validate it when having it plain-text – which is why setting $rcmail_config['imap_auth_type'] = 'PLAIN' in the roundcube configuration "solves" this.

Options

  1. Stick with PLAIN/LOGIN:
    • fine with Roundcube and IMAP on the same server, as long as users connect with HTTPS
    • fine with access from mail clients, as long as the connection is secured (IMAPS/POP3S/SMTPS)
    • a security hole with unencrypted traffic
  2. Store the passwords plain-text
    • all kind of auth mechanisms can be used, which is a pro
    • having all your users' passwords plain-text in a file/database is an absolute no-go
  3. Store the passwords using CRAM-MD5
    • gives you at least CRAM-MD5, which most clients support
    • still leaves the option of using PLAIN/LOGIN
    • must be supported by your administrative tools
      • some of them might need to revert to 3rd party tools for encryption (e.g. PostfixAdmin uses /usr/sbin/doveadm pw), which makes the clear-text password appear shortly in the process list each time it is invoked
    • other 3rd party tools (plugins/addons etc.) might be an issue

I'm still struggling which path to go – with only #2 definitely ruled-out (I don't want to make presents to potential hackers ;)

1

I think, the issue is try to use CRAM-MD5 auth mechanism with "crypt" field from the DB.

In your log:

Dec 31 20:14:45 localhost authdaemond: SQL query: SELECT id, **crypt**, '', uid, gid, home, concat(home,'/',maildir), '', name, '' FROM users WHERE id = '[email protected]'  AND (enabled=TRUE)
Dec 31 20:14:45 localhost authdaemond: authpgsql: REJECT - try next module
Dec 31 20:14:45 localhost authdaemond: FAIL, all modules rejected
Dec 31 20:14:45 localhost imapd-ssl: LOGIN FAILED, **method=CRAM-MD5**, ip=[::ffff:127.0.0.1]

That means, on the SQL query you on get the "crypt" field, the authdaemond can't read the plain password, then the CRAM-MD5 don't work. Cleartext passwords allow CRAM-MD5 authentication to be implemented.

To fix:

  1. You can change the auth mechanism of the client (roundcube) to PLAIN or LOGIN. This is compatible with crypt field.
  2. Change at authpgsqlrc file. Set PGSQL_CLEAR_PWFIELD to find "clear" field and comment PGSQL_CRYPT_PWFIELD. So the authdaemond will do a sql query to find the clear text password.

I hope this work for you.

3
  • Ouch for #2 – hackers will love you for that. But yes, it would work ;)
    – Izzy
    Aug 11, 2015 at 17:06
  • That's depends of the full settings, means you can store the password in the DB with AES, GPG, CRAM-MD5 scheme etc... but everything depends how you connect to the DB. If the DB is remote, and don't use SSL/VPN the AES is not and option. Or you have to find other way to validate the password with CRAM-MD5. But in the end, the IMAP server need to read the plain password or CRAM-MD5 scheme to use CRAM-MD5 Mechanisms. Aug 11, 2015 at 17:15
  • That sounds like some of the ideas I'm after (see my question here). As long as the passwords are not stored real plain-text (aka "password"), this becomes valid to me. But isn't storing them CRAM-MD5 a one-way ticket (hash)? I was considering switching from the md5 hashed to CRAM-MD5 hashed passwords in the DB, if that's feasible. Looking forward to hints on that (over at my question, of course – when it makes sense, we still can leave a summary here :)
    – Izzy
    Aug 11, 2015 at 19:37
0

Maybe is the configuration of roundcube:

I'm not 100% but the default configuration of roundcube use "PLAIN" auth, so you can change it at config file and test:

// IMAP AUTH type (DIGEST-MD5, CRAM-MD5, LOGIN, PLAIN or null to use
// best server supported one)
// $rcmail_config['imap_auth_type'] = LOGIN;
$rcmail_config['imap_auth_type'] = null;

In the old versions (0.3.1) of roundcube you only has "auth", "plain" or "check", like this:

// IMAP auth type. Can be "auth" (CRAM-MD5), "plain" (PLAIN) or "check" to auto detect.
// Optional, defaults to "check"
$rcmail_config['imap_auth_type'] = "auth";

Depend the version you are using.

1
  • Pretty close, just the other way around: default setting is null, which fails with CRAM-MD5 for some reason. Explicitly setting it to PLAIN worked for me. As in my case it's a local connection (RC and IMAP are on the same machine), I can live with this work-around – though I've got no idea why CRAM-MD5 is an option here if it doesn't work, and prefer it fixed :)
    – Izzy
    Aug 11, 2015 at 15:10

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