AD + SSSD

If you have host in the AD with the SSSD then your root user can be any user from the domain. So

%groupname ALL=(ALL) NOPASSWD:ALL

would actually give permissions to all users from the “groupname” to become any AD user they want, and if they’re SSH’ng the localhost then, they would have Kerberos ticket as well. It is not actually that evident, but Active Directory is an identity provider, so if you are superuser on the host — you can be AD user on the host.

Debugging IDM

One of the most frequent cases I have is that “sometimes” and “somewhere” user is not getting authenticated. Trying to SSH to the host works for some users not always, “id username” returns errors sometimes — it’s all the same problem in the environment with LDAP replication. It does not actually matter what kind of the LDAP server or domain controller is being used, always check:

    1. Enable debug log on the client. If the client is SSSD, add “debug_level = 9” to the /etc/sssd/sssd.conf and then restart it. Invalidate its cache if possible.
    2. Repeat the test so you would see the error.
    3. Collect the log file from the client. You would see what server it has queried to get the information.
    4. Check server’s log. Most likely there is no requested information on this LDAP instance due to replication issues.

This would help to identify and fix the problem.

Parsing sssd debug log

Lol, hope to add more in furure

grep -v "timed event" |grep -v "timer event"|grep -v "Requesting"|grep -v "SBUS"|grep -v "callback"|grep -v "dispatch"|grep -v "a sysbus message"|grep -v "No sub-attributes for" |grep -v "reusing cached connection" |grep -v "nesting:"|grep -v "sbus_remove_watch"|grep -v "be_client_destructor"|grep -v "sdap_process_result"|grep -v "Comparing LDAP with LDAP" |grep -v "Message type:"|grep -v "unenforced gpo skipped"

More .bashrc improvements

I need to see long path and host name. And not to lose command line space at the same time:

BOLD="\[$($TTY  && /usr/bin/tput bold)\]"
COLOR_BLACK="\[$($TTY  && /usr/bin/tput setaf 0)\]"
COLOR_RED="\[$($TTY  && /usr/bin/tput setaf 1)\]"
COLOR_GREEN="\[$($TTY  && /usr/bin/tput setaf 2)\]"
COLOR_YELLOW="\[$($TTY && /usr/bin/tput setaf 3)\]"
COLOR_BLUE="\[$($TTY  && /usr/bin/tput setaf 4)\]"
COLOR_MAGENTA="\[$($TTY  && /usr/bin/tput setaf 5)\]"
COLOR_CYAN="\[$($TTY  && /usr/bin/tput setaf 6)\]"
COLOR_WHITE="\[$($TTY  && /usr/bin/tput setaf 7)\]"
COLOR_GRAY="\[$($TTY  && /usr/bin/tput setaf 8)\]"
RESET="\[$($TTY  && /usr/bin/tput sgr0)\]"



function prompt_command  {     
    local TIMESTAMP="${BOLD}${COLOR_GRAY}\D{%d/%m %H:%M:%S}${RESET}"
    local CURPWD="${BOLD}${COLOR_BLUE}${PWD/#${HOME}/~}${RESET}"

    PS1="\n┌[${BOLD}\u@${COLOR_RED}\h${RESET}]─[${CURPWD}]\n"
    PS1=${PS1}"└─"${TIMESTAMP}${BOLD}"-> "

}

PROMPT_COMMAND=prompt_command

Opera Neon

Funny browser: mouse multitouch, gestures, extensions, settings import, vpn, turbo, profile login – that’s all does not work. No Linux version. But tab management is really neat!

Strange things: there are 3 search engines pre-configured: google, Yandes and mail.ru. I am not located in the Russia though!

Google group calendars in Evolution Mail

If your organization uses Google Apps as mail service but you are using Evolution, there is no evident way to view and edit shared group calendars until recent versions. To add group calendar you need:

  1. go to calendar settings on web
  2. Calendar Address: -> ID (somenting like example.com_1d32345331343234213832@resource.calendar.google.com)
  3. Evolution -> New Calendar -> Google
  4. User name -> this ID
  5. Auth with usual name-pass or other means you use (Kerberos, OTP) in the window appear.
  6. Allow Evolution to use the Google’s resources.

DKIM=temperror

Recently I have checked my messages headers of the mail that comes from the andreybondarenko.com MX and found that Google shows that my DKIM signature is invalid:

Authentication-Results: mx.google.com; dkim=temperror (no key for
 signature) header.i=@andreybondarenko.com;

In the spam score section:

DKIM_SIGNED,T_DKIM_INVALID

However the header itself is present:

DKIM-Filter: OpenDKIM Filter v2.10.3 andreybondrenko.com CE25780BAC
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=andreybondarenko.com; s=default; t=1483634085;
        bh=w00tuUhwty0/5n/YHiopiY3PpnqKT5BLK9l6TkDNUUk=;
        h=Subject:From:Reply-To:To:Date:From;
        b=J5qB5RF9lrOho1wBpLyLi5a6CwIHZK1sugCr2wpwnPKwEg76RFv2/y8xaiwquqftX
         VhTJH9NLJXcPdu8k8/zN/sc8P1RksNR9EvDw6k2YNEKoeMsKMGgyMC4kAAhcT31IgX
         eqnIqWxhVTVdjRqrqzNPn0wuBbGJgO2bwmFcVsy8=

I have found that it’s quite common configuration error of the OpenDKIM, the selector you choose to store key can be chosen randomly, but the TXT record should match /etc/opendkim.conf. In my case:

##  Defines the name of the selector to be used when signing messages.
Selector   default

But the DNS record:

[user@andreybondarenko ~]$ dig TXT mail._domainkey.andreybondarenko.com

;; ANSWER SECTION:
mail._domainkey.andreybondarenko.com. 1800 IN TXT "v=DKIM1\; k=rsa\; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCdGRWtWPPZVIg0fy7Pr0+rsBsoL6Imt1GBE/QRd3X5Izv1iAJFUsOtea
f9TI9EO/YFwoLLahzuoZM1oUU4ED3fHlItEnqXCKQhX8Zripi7gfIO+DRFEhGuQtG6OIuA6+c3ivao7DTPk/IFqY7MG5M3wMvAfV+
eIBf1VjmajSwe3wIDAQAB"

Changing ‘Selector’ to ‘mail’ and restating opendkim (it’s faster then change DNS):

Authentication-Results: mx.google.com; dkim=pass
 header.i=@andreybondarenko.com;

In the spam score section:

DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU