Re: pg_ident mapping Kerberos Usernames

On Sat, Sep 9, 2017 at 6:44 PM, <techmail+pgsql(at)dangertoaster(dot)com> wrote:

> Hi,
>
> I'm trying to get pg_ident to map "user1" and "user1(at)A(dot)DOMAIN(dot)TLD" to
> "user1" in postgres, or vice versa. I'm not picky about which way works.
>
> Kerberos authentication works. I've gotten "user1" to login successfully
> with a Kerberos ticket, but I'm not able to get "user1(at)A(dot)DOMAIN(dot)TLD" to
> match.
>
> Environment:
> * PostgreSQL 9.6 from PostgreSQL repos
> * CentOS 7
> * FreeIPA for Kerberos, LDAP, etc.
> * Realm A.DOMAIN.TLD
> * "user1" database exists
> * "user1" role exists
> * Logging into CentOS usernames are configured to drop the domain, so they
> appear as "user1" rather then "user1(at)a(dot)domain(dot)tld".
>
>
> pg_hba.conf:
>
> local all postgres peer
> host all all 127.0.0.1/32 md5
> host all all ::1/128 md5
> host all all 192.168.1.0/24 gss
> include_realm=1 map=testnet krb_realm=A.DOMAIN.TLD #This is on one line.
> Thunderbird is truncating lines.
>
>
> pg_ident.conf:
>
> testnet /^([0-9A-Za-z_-]+)@A\.DOMAIN\.TLD$ \1
> testnet /^([0-9A-Za-z_-]+)$ \1
>
>
> Regex that works for both in regexr.com:
>
> /^([0-9A-Za-z-_]+)(@A\.DOMAIN\.TLD)?$/gm
>
>
> Command and lines from pg_log:
>
> $ psql -h db0 # Logged in as user1 with Kerberos ticket
>
> < 2017-09-09 19:50:49.376 CDT - 192.168.1.201 [unknown] > LOG: connection
> received: host=192.168.1.201 port=44918
> < 2017-09-09 19:50:49.398 CDT - 192.168.1.201 user1 > LOG: connection
> authorized: user=user1 database=user1
> < 2017-09-09 19:50:50.912 CDT - 192.168.1.201 user1 > LOG: disconnection:
> session time: 0:00:01.537 user=user1 database=user1 host=192.168.1.201
> port=44918
>
> $ psql -h db0 -U user1(at)A(dot)DOMAIN(dot)TLD # Logged in as user1 with Kerberos
> ticket
>
> < 2017-09-09 19:50:54.959 CDT - 192.168.1.201 [unknown] > LOG: connection
> received: host=192.168.1.201 port=44920
> < 2017-09-09 19:50:55.023 CDT - 192.168.1.201 user1(at)A(dot)DOMAIN(dot)TLD > LOG:
> no match in usermap "testnet" for user "user1(at)A(dot)DOMAIN(dot)TLD" authenticated
> as "user1(at)A(dot)DOMAIN(dot)TLD"
> < 2017-09-09 19:50:55.023 CDT - 192.168.1.201 user1(at)A(dot)DOMAIN(dot)TLD >
> FATAL: GSSAPI authentication failed for user "user1(at)A(dot)DOMAIN(dot)TLD"
> < 2017-09-09 19:50:55.023 CDT - 192.168.1.201 user1(at)A(dot)DOMAIN(dot)TLD >
> DETAIL: Connection matched pg_hba.conf line 87: "host all
> all 192.168.1.0/24 gss include_realm=1
> map=testnet krb_realm=A.DOMAIN.TLD"
>
>
> Is this something that is possible, or is it something where I need to
> pick one way to do it?
>

This looks like you are trying to connect with the actual username
user1¡A.DOMAIN.TLD. pg_ident only sets what you are allowed to log in as,
not what it will attempt.

If you are using psql, you are probably doing something like "psql -h
myserver". You need to add the user, so "psql -h myserver -U user1", to
instruct it of which username to actually use for the login.

--
Magnus Hagander
Me: https://www.hagander.net/ <http://www.hagander.net/>
Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>