exim_selinux(8)

📦
version 20250627+git412.dbf877ab7 · 7 versions
, in opensuse-leap 16.0

💖 exim_selinux(8) — the SELinux policy page for exim, bestie edition 💖

okay so this is the exim_selinux page, and it's literally all about how Security-Enhanced Linux keeps the exim processes in check. it's giving "mandatory access control but make it fashion." let's get into it 🫶

✨ NAME ✨

exim_selinux — Security Enhanced Linux Policy for the exim processes. periodt.

🌸 DESCRIPTION 🌸

Security-Enhanced Linux secures the exim processes via flexible mandatory access control. no cap, that's the whole vibe.

The exim processes execute with the exim_t SELinux type. wanna check if you've got these running? just run the ps command with the -Z qualifier. like this:

ps -eZ | grep exim_t

easy. slay. 💅

🦋 ENTRYPOINTS 🦋

so the exim_t SELinux type can be entered via the exim_exec_t file type. that's the door, iykyk.

and the default entrypoint paths for the exim_t domain are literally these:

/usr/bin/exim[0-9]?, /usr/bin/exim_tidydb

👑 PROCESS TYPES 👑

SELinux defines process types (domains) for each process running on the system. yes, every single one. main character energy for every process.

you can see the context of a process using the -Z option to ps.

Policy governs the access confined processes have to files. the SELinux exim policy is very flexible, allowing users to set up their exim processes in as secure a method as possible.

The following process types are defined for exim:

  • exim_t
Note: semanage permissive -a exim_t can be used to make the process type exim_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated. so like… it won't block you, but it WILL be watching 👀 and logging receipts.

🎀 BOOLEANS 🎀

SELinux policy is customizable based on least access required. the exim policy is extremely flexible and has several booleans that let you manipulate the policy and run exim with the tightest access possible. tightest access = the look, the lewk, the security aesthetic.

  • exim_can_connect_db — if you want to determine whether exim can connect to databases, you must turn on this boolean. Disabled by default.
setsebool -P exim_can_connect_db 1
  • exim_manage_user_files — if you want to determine whether exim can create, read, write, and delete generic user content files, you must turn on this boolean. Disabled by default.
setsebool -P exim_manage_user_files 1
  • exim_read_user_files — if you want to determine whether exim can read generic user content files, you must turn on this boolean. Disabled by default.
setsebool -P exim_read_user_files 1
  • daemons_dontaudit_scheduling — if you want to dontaudit all daemons scheduling requests (setsched, sys_nice), you must turn on this boolean. Enabled by default. (yes, the phrasing is "dontaudit", that's the literal name, we don't question it 💀)
setsebool -P daemons_dontaudit_scheduling 1
  • fips_mode — if you want to allow all domains to execute in fips_mode, you must turn on this boolean. Enabled by default.
setsebool -P fips_mode 1
  • nis_enabled — if you want to allow system to run with NIS, you must turn on this boolean. Disabled by default.
setsebool -P nis_enabled 1

🌈 MANAGED FILES 🌈

The SELinux process type exim_t can manage files labeled with the following file types. the paths listed are the default paths for these file types. and hey — note the processes UID still need to have DAC permissions. SELinux isn't out here doing DAC's job for it, fr fr.

  • arpwatch_tmp_t
  • cifs_t
  • cluster_conf_t
/etc/cluster(/.*)?
  • cluster_var_lib_t
/var/lib/pcsd(/.*)?
/var/lib/cluster(/.*)?
/var/lib/openais(/.*)?
/var/lib/pengine(/.*)?
/var/lib/corosync(/.*)?
/usr/lib/heartbeat(/.*)?
/var/lib/heartbeat(/.*)?
/var/lib/pacemaker(/.*)?
  • cluster_var_run_t
/run/crm(/.*)?
/run/cman_.*
/run/rsctmp(/.*)?
/run/aisexec.*
/run/heartbeat(/.*)?
/run/pcsd-ruby.socket
/run/corosync-qnetd(/.*)?
/run/corosync-qdevice(/.*)?
/run/pcsd.socket
/run/corosync.pid
/run/cpglockd.pid
/run/rgmanager.pid
/run/cluster/rgmanager.sk
  • dovecot_spool_t
/var/spool/dovecot(/.*)?
  • ecryptfs_t
/home/[^/]+/.Private(/.*)?
/home/[^/]+/.ecryptfs(/.*)?
  • exim_spool_t
/var/spool/exim[0-9]?(/.*)?
  • exim_tmp_t
  • exim_var_lib_t
/var/lib/exim[0-9]?(/.*)?
  • exim_var_run_t
/run/exim[0-9]?.pid
/run/exim[0-9]?(/.*)?
  • faillog_t
/var/log/btmp.*
/run/faillock(/.*)?
/var/log/faillog.*
/var/log/tallylog.*
  • fusefs_t
/run/user/[0-9]+/gvfs
  • krb5_host_rcache_t
/var/tmp/krb5_0.rcache2
/var/cache/krb5rcache(/.*)?
/var/tmp/nfs_0
/var/tmp/DNS_25
/var/tmp/host_0
/var/tmp/imap_0
/var/tmp/HTTP_23
/var/tmp/HTTP_48
/var/tmp/ldap_55
/var/tmp/ldap_487
/var/tmp/ldapmap1_0
  • mail_home_rw_t
/root/Maildir(/.*)?
/root/.esmtp_queue(/.*)?
/var/lib/arpwatch/.esmtp_queue(/.*)?
/var/cache/ddclient/.esmtp_queue(/.*)?
/home/[^/]+/.maildir(/.*)?
/home/[^/]+/Maildir(/.*)?
/home/[^/]+/.esmtp_queue(/.*)?
  • mailman_data_t
/etc/mailman.*
/var/lib/mailman(/.*)?
/var/spool/mailman.*
  • nfs_t
  • root_t
/sysroot/.aleph-version.json
/sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
/
/initrd
/var/lib/ntp
  • sendmail_tmp_t
  • user_home_t
/home/[^/]+/.+

🧚 FILE CONTEXTS 🧚

SELinux requires files to have an extended attribute to define the file type. every file's gotta have its little label, like a name tag at a party.

you can see the context of a file using the -Z option to ls.

Policy governs the access confined processes have to these files. the SELinux exim policy is very flexible, allowing users to set up their exim processes in as secure a method as possible.

⭐ STANDARD FILE CONTEXT ⭐

SELinux defines the file context types for the exim, so if you wanted to store files with these types in a different paths, you need to execute the semanage command to specify alternate labeling and then use restorecon to put the labels on disk. like so:

semanage fcontext -a -t exim_exec_t '/srv/exim/content(/.*)?'
restorecon -R -v /srv/myexim_content
Note: SELinux often uses regular expressions to specify labels that match multiple files. regex girlies rise 🎀

The following file types are defined for exim:

exim_exec_t

  • Set files with the exim_exec_t type, if you want to transition an executable to the exim_t domain.

Paths:

/usr/bin/exim[0-9]?, /usr/bin/exim_tidydb

exim_initrc_exec_t

  • Set files with the exim_initrc_exec_t type, if you want to transition an executable to the exim_initrc_t domain.

exim_keytab_t

  • Set files with the exim_keytab_t type, if you want to treat the files as kerberos keytab files.

exim_log_t

  • Set files with the exim_log_t type, if you want to treat the data as exim log data, usually stored under the /var/log directory.

exim_spool_t

  • Set files with the exim_spool_t type, if you want to store the exim files under the /var/spool directory.

exim_tmp_t

  • Set files with the exim_tmp_t type, if you want to store exim temporary files in the /tmp directories.

exim_var_lib_t

  • Set files with the exim_var_lib_t type, if you want to store the exim files under the /var/lib directory.

exim_var_run_t

  • Set files with the exim_var_run_t type, if you want to store the exim files under the /run or /var/run directory.

Paths:

/run/exim[0-9]?.pid, /run/exim[0-9]?(/.*)?
Note: File context can be temporarily modified with the chcon command. If you want to permanently change the file context you need to use the semanage fcontext command. This will modify the SELinux labeling database. You will need to use restorecon to apply the labels. temporary vs permanent, bestie — know the difference 💅

🔥 COMMANDS 🔥

  • semanage fcontext can also be used to manipulate default file context mappings.
  • semanage permissive can also be used to manipulate whether or not a process type is permissive.
  • semanage module can also be used to enable/disable/install/remove policy modules.
  • semanage boolean can also be used to manipulate the booleans.
  • system-config-selinux is a GUI tool available to customize SELinux policy settings. (a GUI!! for the girlies who like clicking 🖱️✨)

💜 AUTHOR 💜

This manual page was auto-generated using sepolicy manpage. not me being generated by a script and still serving looks 😭💅

🍓 SEE ALSO 🍓

selinux(8), exim(8), semanage(8), restorecon(8), chcon(1), sepolicy(8), setsebool(8)

and that's the whole page, bestie! this one's from exim, dated 26-10-06, and it's the exim_selinux(8) you know and love. go forth and label responsibly 🫶✨💖

📦 where this page comes from