postfix_m...r_selinux(8)

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

💅 postfix_master_selinux(8) — the SELinux tea on your postfix_master processes 🎀

okay so bestie, this is the postfix_master_selinux manual page (it's section 8 of the SELinux Policy postfix_master set, iykyk), and it's literally all about the Security Enhanced Linux Policy for the postfix_master processes. buckle up, it's giving security ✨

🌸 NAME 🌸

postfix_master_selinux — Security Enhanced Linux Policy for the postfix_master processes. that's the whole vibe, no cap 💖

🦋 DESCRIPTION 🦋

Security-Enhanced Linux secures the postfix_master processes via flexible mandatory access control. like, flexible and mandatory, iconic behavior honestly 👑

The postfix_master processes execute with the postfix_master_t SELinux type. you can peek and check if you've got these processes running by executing the ps command with the -Z qualifier. for example:

ps -eZ | grep postfix_master_t

go off, ps 🫶

✨ ENTRYPOINTS ✨

The postfix_master_t SELinux type can be entered via the postfix_master_exec_t file type. that's the doorway, bestie 🚪

The default entrypoint paths for the postfix_master_t domain are the following:

/usr/bin/postcat, /usr/bin/postfix, /usr/bin/postlog, /usr/bin/postkick,
/usr/bin/postlock, /usr/bin/postalias, /usr/bin/postsuper,
/usr/libexec/postfix/master

not me listing every single one of them, obsessed 🎀

💜 PROCESS TYPES 💜

SELinux defines process types (domains) for each process running on the system. yes, every single one gets its own little identity, main character energy fr

You can see the context of a process using the -Z option to ps. ngl that -Z is doing a lot of heavy lifting on this page 🔥

Policy governs the access confined processes have to files. SELinux postfix_master policy is very flexible allowing users to setup their postfix_master processes in as secure a method as possible. flexible but secure, the duality of woman 💅

The following process types are defined for postfix_master:

  • postfix_master_t
Note: semanage permissive -a postfix_master_t can be used to make the process type postfix_master_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated. so like, it's chill but it's watching 👀

🍓 BOOLEANS 🍓

SELinux policy is customizable based on least access required. postfix_master policy is extremely flexible and has several booleans that allow you to manipulate the policy and run postfix_master with the tightest access possible. tightest access, tightest fit, slay 💜

If you want to dontaudit all daemons scheduling requests (setsched, sys_nice), you must turn on the daemons_dontaudit_scheduling boolean. Enabled by default.

setsebool -P daemons_dontaudit_scheduling 1

If you want to allow all domains to execute in fips_mode, you must turn on the fips_mode boolean. Enabled by default.

setsebool -P fips_mode 1

If you want to allow system to run with NIS, you must turn on the nis_enabled boolean. Disabled by default.

setsebool -P nis_enabled 1

three booleans, three little toggles of destiny 🌈

🌼 MANAGED FILES 🌼

The SELinux process type postfix_master_t can manage files labeled with the following file types. The paths listed are the default paths for these file types. note the processes UID still need to have DAC permissions — SELinux isn't out here doing everything for you, bestie 😭

🌟 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

🌟 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

🌟 mailman_data_t

/etc/mailman.*
/var/lib/mailman(/.*)?
/var/spool/mailman.*

🌟 postfix_data_t

/var/lib/postfix.*

🌟 postfix_private_t

/var/spool/postfix/private(/.*)?

🌟 postfix_prng_t

/etc/postfix/prng_exch

🌟 postfix_spool_t

/var/spool/postfix.*
/var/spool/postfix/defer(/.*)?
/var/spool/postfix/flush(/.*)?
/var/spool/postfix/deferred(/.*)?
/var/spool/postfix/maildrop(/.*)?

🌟 postfix_var_run_t

/var/spool/postfix/pid/.*

🌟 root_t

/sysroot/.aleph-version.json
/sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
/
/initrd
/var/lib/ntp

like, that's a lot of file types and we respect every single one of them 💅

🧚 FILE CONTEXTS 🧚

SELinux requires files to have an extended attribute to define the file type. it's giving "files with lore" ✨

You can see the context of a file using the -Z option to ls. yes -Z again, it's the moment 🎀

Policy governs the access confined processes have to these files. SELinux postfix_master policy is very flexible allowing users to setup their postfix_master processes in as secure a method as possible. same flex, same security, no notes 🔥

💖 STANDARD FILE CONTEXT 💖

SELinux defines the file context types for the postfix_master, 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.

semanage fcontext -a -t postfix_master_exec_t
'/srv/postfix_master/content(/.*)?'
restorecon -R -v /srv/mypostfix_master_content

Note: SELinux often uses regular expressions to specify labels that match multiple files. regex girlies rise 🙈

The following file types are defined for postfix_master:

⭐ postfix_master_exec_t

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

Paths:

/usr/bin/postcat, /usr/bin/postfix, /usr/bin/postlog,
/usr/bin/postkick, /usr/bin/postlock, /usr/bin/postalias,
/usr/bin/postsuper, /usr/libexec/postfix/master
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, the eternal struggle 😭

🫶 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.

GUI tool girlies, we see you 👑

👑 AUTHOR 👑

This manual page was auto-generated using sepolicy manpage. auto-generated and still ate, periodt 💅

🌈 SEE ALSO 🌈

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

go read them, they're all besties too 🦋

and that's the page, bestie 💖 this was postfix_master from the 26-10-06 era, tagged under postfix_m...r_selinux(8) at the bottom, which is honestly the most truncated little footer ever and I kind of love it for that. mwah 🎀✨

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