Moving to new password scheme
dovecot is setup on a system with MD5-CRYPT password scheme for all users, and I would like to update this to something that is secure, probably SSHA256-CRYPT, but I want to do this seamlessly without the users having to jump through any hoops.
The users are in mySQL (managed via postfixadmin) and the mailbox record simply stores the hash in the password field. Users access their accounts though IMAP MUAs or Roundcube.
How would I setup my system so that if a user logs in and still has a $1$ password (MD5-CRYPT) their password will be encoded to the new SHCEME and then the SQL row updated with the $5$ password instead? Something where they are redirected after authentication to a page that forces them to renter their password (or choose a new one) is acceptable.
And, while I am here, is it worthwhile to set the -r flag to a large number (like something over 100,000 which sets takes about 0.25 seconds to do on my machine)?
-- Apple broke AppleScripting signatures in Mail.app, so no random signatures.
Il 24/01/2017 23:29, @lbutlr ha scritto:
Hi,
you can convert password scheme during the login:
http://wiki2.dovecot.org/HowTo/ConvertPasswordSchemes
Ciao
-- Alessio Cecchi Postmaster @ http://www.qboxmail.it https://www.linkedin.com/in/alessice
Thanks, I started to look into that and got stopped no the first step
If I set that and reload dovecot users cannot login.
dovecot: auth: Fatal: userdb prefetch: No args are supported: /etc/dovecot/dovecot-sql.conf.ext dovecot: master: Error: service(auth): command startup failed, throttling for 8 secs dovecot: imap-login: Disconnected: Auth process broken (disconnected before auth was ready, waited 4 secs): user=<>,
2.2.27 (c0f36b0): /usr/local/etc/dovecot/dovecot.conf
OS: FreeBSD 10.3-RELEASE-p11 i386
auth_failure_delay = 5 secs auth_mechanisms = PLAIN LOGIN default_client_limit = 4096 default_process_limit = 1024 default_vsz_limit = 768 M disable_plaintext_auth = no first_valid_uid = 89 imap_id_log = * lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes login_log_format_elements = user=<%u> %r %m %c mail_location = maildir:~/Maildir mail_max_userip_connections = 90 namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox NotJunk { auto = subscribe } mailbox Sent { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } protocols = imap service auth { unix_listener /var/spool/postfix/private/auth { mode = 0666 } } service imap-login { inet_listener imaps { port = 993 ssl = yes } } service imap-postlogin { executable = script-login /usr/local/etc/dovecot/afterlogin.sh user = $default_internal_user } ssl_cert = </usr/local/etc/dehydrated/certs/covisp.net/fullchain.pem ssl_key = # hidden, use -P to show it ssl_protocols = !SSLv2 !SSLv3
userdb { driver = passwd } userdb { args = /etc/dovecot/dovecot-sql.conf.ext default_fields = uid=vpopmail gid=vchkpw mail_location=/usr/local/virtual/%u mail=maildir:/usr/local/virtual/%u driver = sql }
-- Apple broke AppleScripting signatures in Mail.app, so no random signatures.
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On Wed, 25 Jan 2017, @lbutlr wrote:
I don't see no prefetch in your config. The error may indicate that you replaced driver = sql by driver = prefetch, which is wrong.
http://wiki2.dovecot.org/UserDatabase/Prefetch
The idea described on the Wiki page is:
During login, most often the same data is collected from the passdb as
later from the userdb, therefore you can collect *all* information you
would retrieve from userdb { } within passdb queries (that's why the home
as userdb_home,
uid as userdb_uid, gid as userdb_gid, '%w' as userdb_plain_pass entries;
the prefix userdb_ indicates that data) and store it for later use by the
prefetch database.
That's why the prefetch userdb has to preceed the other ones, because if the passdb query filled in the values, the later userdb entries are ignored.
You've noticed the '%w' as userdb_plain_pass ? That stores the plain password (if any) to the virtual prefetch userdb entry as field plain_pass.
Those fields are available later as environment variables, that's why /usr/local/etc/popafter.sh
may use:
1 #!/bin/sh
2 DOVECOTPW=$(doveadm pw -s SHA512-CRYPT -p $PLAIN_PASS)to access it.
Now, you are using two passdb's. the PAM passdb won't support this method, I guess.
Steffen Kaiser -----BEGIN PGP SIGNATURE----- Version: GnuPG v1
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No, when I changed userdb { driver = passwd } to prefetch everything failed, so I changed it back immediately so people could login. That was the firs step on the page and I couldn’t get past it.
The error may indicate that you replaced driver = sql by driver = prefetch, which is wrong.
driver = sql is in the imap/sql section. The one I tried changing was the bare userdb declaration the just said driver - passwd.
I guess I need to ADD another userdb declaration for the prefetch.
Does the other int he file matter? I have local users stuff first and then the sql stuff later, but I’m not sure if that matters.
So Place it first (or at least before all the sql stuff)?
You've noticed the '%w' as userdb_plain_pass ? That stores the plain password (if any) to the virtual prefetch userdb entry as field plain_pass.
OK.
Now, you are using two passdb's. the PAM passdb won't support this method, I guess.
No, I’m not expecting it to. the local users are mostly my admin accounts and I can just change the passwords on those manually without an issue.
I’ll keep at it. Thanks.
-- Apple broke AppleScripting signatures in Mail.app, so no random signatures.
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On Wed, 25 Jan 2017, @lbutlr wrote:
yes, userdb's are checked in the same order as they appear in the config file(s).
yep.
Steffen Kaiser -----BEGIN PGP SIGNATURE----- Version: GnuPG v1
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OK, I have the dovecot.conf stuff working so that it calls the external script and I have that script spitting out the login and a SHA256-CRYPT password with hash:
Thu Jan 26 06:45:54 MST 2017 USER: xander@xanmax.com {SHA512-CRYPT}$6$CfKc0NdiRkWOisjL$kHAx2oxB…
SO, feeling pretty good about that. However, i want to check one more thing, before I start issuing the commands to update the sql database, I will need to update postfixadmin (I think) to use dovecot:SHA256-CRYPT instead of its default $CONF['encrypt'] = 'md5crypt'; yes?
And this means that until someone logs in to their mail, they will not be able to login to postfixadmin, right?
(This is not a problem, I just want to be sure)
-- Apple broke AppleScripting signatures in Mail.app, so no random signatures.
On Jan 25, 2017, at 4:57 AM, Steffen Kaiser <skdovecot@smail.inf.fh-brs.de> wrote:
yes, userdb's are checked in the same order as they appear in the config file(s).
Thanks for all the help, got everyone migrated over to SHA256-CRYPT now.
-- Apple broke AppleScripting signatures in Mail.app, so no random signatures.
participants (4)
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＠lbutlr
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Alessio Cecchi
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KSB
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Steffen Kaiser