Security-Enhanced Linux secures the sendmail processes via flexible mandatory access control.
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 gitisis daemon to send mail, you must turn on the gitosis_can_sendmail boolean.
setsebool -P gitosis_can_sendmail 1
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd serve for the sendmail_t, you must turn on the authlogin_nsswitch_use_ldap boolean.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to allow confined applications to run with kerberos for the sendmail_t, you must turn on the kerberos_enabled boolean.
setsebool -P kerberos_enabled 1
You can see the context of a file using the -Z option to lsP 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.
You can see the context of a process using the -Z option to psP 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 PROCESS_TYPE can be used to make a process type permissive. Permissive process types are not denied access by SELinux. AVC messages will still be generat