selinux July 2022

selinux@lists.fedoraproject.org

1 participants
4 discussions

Not possible to specify smtp password for setroubleshootd?
by Matt Kinni 09 Jun '24

09 Jun '24

Hello, I run a Fedora 35 server and would like setroubleshootd to send email alerts for avc denials, but I'm having trouble configuring this due to the apparent lack of support for configuring an smtp password. The out of the box setroubleshoot.conf sets > smtp_host = localhost > smtp_port = 25 > from_address = SELinux_Troubleshoot , but there is no config parameter for smtp password. For this to actually work on a machine acting as an MTA (I have postfix running locally), the mail server would have to be configured to allow unauthenticated port 25 connections to masquerade as any local system user, which no decent postfix setup would allow. I am not a python programmer, but in my reading of https://pagure.io/setroubleshoot/blob/main/f/framework/src/setroubleshoot/e…, it doesn't appear there is any built in way to support authenticated email sending despite the underlying smtplib being able to do it. I would suggest either a) adding password support for smtplib, or/and b) adding an option to send mail using the sendmail binary, which allows postfix to recognize the running user without any password needed. Has anyone else run into problems deploying the setroubleshootd email alerts in practice? email_alert.py appears simple enough to hack in password support, but I feel a security oriented project like selinux shouldn't require an insecure mail setup in order to send its alerts. Any tips are welcome, Thanks, Matt

2 4

certmonger post-save scripts & certmonger_unconfined_t domain
by Sam Morris 06 Jun '24

06 Jun '24

Certmonger allows for the configuration of a post-save command to be run after it has obtained new certificates. This can be used to copy the key & certificates out of wherever certmonger is allowed to put them, and save them elsewhere with a particular owner/group, combine the certificate & chain into a single file as required by some software, etc. The problem comes with SELinux which prevents my post-save scripts from being able to do all of that. I thought the solution was to give the scripts the context of certmonger_unconfined_exec_t, which would cause a transition to the certmonger_unconfined_t domain which is as its name suggests unconfined; but I can't get this to work. I'm trying to use runcon to simulate certmonger executing a fake script: # cat /tmp/fakescript #!/bin/bash set -eu id -Z # /tmp/fakescript unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 # ls -Z /tmp/fakescript unconfined_u:object_r:certmonger_unconfined_exec_t:s0 /tmp/fakescript # runcon system_u:system_r:certmonger_t:s0 /tmp/fakescript runcon: ‘/tmp/fakescript’: Permission denied Here is the avc denial: ---- type=PROCTITLE msg=audit(27/04/21 16:16:47.156:153492) : proctitle=runcon system_u:system_r:certmonger_t:s0 /tmp/fakescript type=SYSCALL msg=audit(27/04/21 16:16:47.156:153492) : arch=x86_64 syscall=execve success=no exit=EACCES(Permission denied) a0=0x7ffd8aa768ab a1=0x7ffd8aa75888 a2=0x7ffd8aa75898 a3=0x0 items=0 ppid=177795 pid=177796 auid=sam.admin uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=pts5 ses=103 comm=runcon exe=/usr/bin/runcon subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) type=AVC msg=audit(27/04/21 16:16:47.156:153492) : avc: denied { entrypoint } for pid=177796 comm=runcon path=/tmp/fakescript dev="dm-0" ino=33563064 scontext=system_u:system_r:certmonger_t:s0 tcontext=unconfined_u:object_r:certmonger_unconfined_exec_t:s0 tclass=file permissive=0 Even though: # sepolicy transition -s certmonger_t -t certmonger_unconfined_t certmonger_t @ certmonger_unconfined_exec_t --> certmonger_unconfined_t Diving in a little deeper, I can see that certmonger can execute the file: # sesearch -s certmonger_t -t certmonger_unconfined_exec_t -c file -p execute -A allow certmonger_t certmonger_unconfined_exec_t:file { execute execute_no_trans getattr ioctl map open read }; ... and that the file type is an entrypoint for the certmonger_unconfined_t domain: # sesearch -s certmonger_unconfined_t -t certmonger_unconfined_exec_t -c file -p entrypoint -A allow certmonger_unconfined_t certmonger_unconfined_exec_t:file { entrypoint execute getattr ioctl lock map open read }; ... and that transition is permitted from certmonger_t: # sesearch -s certmonger_t -t certmonger_unconfined_t -c process -p transition -A allow certmonger_t certmonger_unconfined_t:process transition; Which leaves me scratching my head, unsure why it doesn't work in practice... -- Sam Morris <https://robots.org.uk/> PGP: rsa4096/CAAA AA1A CA69 A83A 892B 1855 D20B 4202 5CDA 27B9

2 4

Re: Samba and Borg/fuse denied - ?
by lejeczek 22 Jul '22

22 Jul '22

On 21/07/2022 17:11, Robin Lee Powell wrote: > > On Thu, Jul 21, 2022 at 02:33:31PM +0100, lejeczek wrote: >> Hi guys >> >> I see that: >> -> $ getsebool samba_share_fusefs >> samba_share_fusefs --> on >> >> but unless I put 'permissive' on or: >> -> $ semanage permissive --add smb_t >> then Samba will have not access to borg fuse mounts and denials are silent. >> >> Anybody would also think this can go as BZ or request for "enhancement"? >> All thoughts share are greatly appreciated. > I can't help with the actual issue, but the incantation for seeing > the silent denials is probably: sudo semanage dontaudit off My concern here is about 'samba_share_fusefs' - unless it's not what I thought it was. I see other domains have '_use_fusefs' - perhaps that is what Samba needs too @devel ? selinux-policy-3.14.3-104.el8.noarch thanks, L.

1 0

Samba and Borg/fuse denied - ?
by lejeczek 21 Jul '22

21 Jul '22

Hi guys I see that: -> $ getsebool samba_share_fusefs samba_share_fusefs --> on but unless I put 'permissive' on or: -> $ semanage permissive --add smb_t then Samba will have not access to borg fuse mounts and denials are silent. Anybody would also think this can go as BZ or request for "enhancement"? All thoughts share are greatly appreciated. many thanks, L.

1 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

selinux July 2022