sendmail_selinux(8) - Linux man page

Name

sendmail_selinux - Security Enhanced Linux Policy for the sendmail processes

Description

Security-Enhanced Linux secures the sendmail processes via flexible mandatory access control.

The sendmail processes execute with the sendmail_t SELinux type. You can check if you have these processes running by executing the ps command with the -Z qualifier.

For example:

ps -eZ | grep sendmail_t

Entrypoints

The sendmail_t SELinux type can be entered via the "sendmail_exec_t,mta_exec_type" file types. The default entrypoint paths for the sendmail_t domain are the following:"

/usr/lib(64)?/sendmail, /bin/mail(x)?, /usr/sbin/sendmail(.sendmail)?, /usr/bin/esmtp, /usr/sbin/ssmtp, /usr/sbin/rmail, /var/qmail/bin/sendmail, /usr/sbin/sendmail.postfix, /usr/lib/courier/bin/sendmail

Process Types

SELinux defines process types (domains) for each process running on the system

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

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

The following process types are defined for sendmail:

sendmail_t

Note: semanage permissive -a sendmail_t

can be used to make the process type sendmail_t permissive. Permissive process types are not denied access by SELinux. AVC messages will still be generated.

Booleans

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

If you want to allow http daemon to send mail, you must turn on the httpd_can_sendmail boolean.

setsebool -P httpd_can_sendmail 1

If you want to allow syslogd daemon to send mail, you must turn on the logging_syslogd_can_sendmail boolean.

setsebool -P logging_syslogd_can_sendmail 1

If you want to allow http daemon to send mail, you must turn on the httpd_can_sendmail boolean.

setsebool -P httpd_can_sendmail 1

If you want to allow syslogd daemon to send mail, you must turn on the logging_syslogd_can_sendmail boolean.

setsebool -P logging_syslogd_can_sendmail 1

File Contexts

SELinux requires files to have an extended attribute to define the file type.

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

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

The following file types are defined for sendmail:

sendmail_exec_t

- Set files with the sendmail_exec_t type, if you want to transition an executable to the sendmail_t domain.

sendmail_initrc_exec_t

- Set files with the sendmail_initrc_exec_t type, if you want to transition an executable to the sendmail_initrc_t domain.

sendmail_keytab_t

- Set files with the sendmail_keytab_t type, if you want to treat the files as kerberos keytab files.

sendmail_log_t

- Set files with the sendmail_log_t type, if you want to treat the data as sendmail log data, usually stored under the /var/log directory.

sendmail_tmp_t

- Set files with the sendmail_tmp_t type, if you want to store sendmail temporary files in the /tmp directories.

sendmail_var_run_t

- Set files with the sendmail_var_run_t type, if you want to store the sendmail files under the /run directory.

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.

Managed Files

The SELinux process type sendmail_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.

anon_inodefs_t

dovecot_spool_t

/var/spool/dovecot(/.*)?

etc_aliases_t

/etc/postfix/aliases.*

/etc/aliases

/etc/aliases.db

/etc/mail/aliases

/etc/mail/aliases.db

initrc_tmp_t
mail_home_rw_t

/root/Maildir(/.*)?

/home/[^/]*/Maildir(/.*)?

mail_spool_t

/var/mail(/.*)?

/var/spool/imap(/.*)?

/var/spool/mail(/.*)?

mnt_t

/mnt(/[^/]*)

/mnt(/[^/]*)?

/rhev(/[^/]*)?

/media(/[^/]*)

/media(/[^/]*)?

/etc/rhgb(/.*)?

/media/.hal-.*

/net

/afs

/misc

/rhev

mqueue_spool_t

/var/spool/(client)?mqueue(/.*)?

nfs_t
procmail_tmp_t
sendmail_log_t

/var/log/mail(/.*)?

/var/log/sendmail.st.*

sendmail_tmp_t
sendmail_var_run_t

/var/run/sendmail.pid

/var/run/sm-client.pid

tmp_t

/tmp

/usr/tmp

/var/tmp

/var/tmp/vi.recover

user_home_t

/home/[^/]*/.+

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.

Author

This manual page was auto-generated using sepolicy manpage by mgrepl.