Security-Enhanced Linux secures the spamd processes via flexible mandatory access control.
The spamd processes execute with the spamd_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 spamd_t
The spamd_t SELinux type can be entered via the spamd_exec_t file type.
The default entrypoint paths for the spamd_t domain are the following:
/usr/bin/spamd, /usr/bin/pyzord, /usr/sbin/spamd, /usr/sbin/spampd, /usr/bin/mimedefang, /usr/bin/mimedefang-multiplexor, /usr/libexec/mimedefang-wrapper
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux spamd policy is very flexible allowing users to setup their spamd processes in as secure a method as possible.
The following process types are defined for spamd:
spamd_update_t, spamd_t
Note: semanage permissive -a spamd_t can be used to make the process type spamd_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
If you want to allow spamd to read/write user home directories, you must turn on the spamd_enable_home_dirs boolean. Enabled by default.
setsebool -P spamd_enable_home_dirs 1
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd server, you must turn on the authlogin_nsswitch_use_ldap boolean. Disabled by default.
setsebool -P authlogin_nsswitch_use_ldap 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 confined applications to run with kerberos, you must turn on the kerberos_enabled boolean. Enabled by default.
setsebool -P kerberos_enabled 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
If you want to allow confined applications to use nscd shared memory, you must turn on the nscd_use_shm boolean. Enabled by default.
setsebool -P nscd_use_shm 1
You can see the types associated with a port by using the following command:
semanage port -l
Policy governs the access confined processes have to these ports. SELinux spamd policy is very flexible allowing users to setup their spamd processes in as secure a method as possible.
The following port types are defined for spamd:
Default Defined Ports: tcp 783,10026,10027
The SELinux process type spamd_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.
antivirus_db_t
/var/amavis(/.*)?
/var/clamav(/.*)?
/var/lib/clamd.*
/var/lib/amavis(/.*)?
/var/lib/clamav(/.*)?
/var/virusmails(/.*)?
/var/opt/f-secure(/.*)?
/var/spool/amavisd(/.*)?
/var/lib/clamav-unofficial-sigs(/.*)?
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
/var/run/crm(/.*)?
/var/run/cman_.*
/var/run/rsctmp(/.*)?
/var/run/aisexec.*
/var/run/heartbeat(/.*)?
/var/run/corosync-qnetd(/.*)?
/var/run/corosync-qdevice(/.*)?
/var/run/corosync.pid
/var/run/cpglockd.pid
/var/run/rgmanager.pid
/var/run/cluster/rgmanager.sk
ecryptfs_t
/home/[^/]+/.Private(/.*)?
/home/[^/]+/.ecryptfs(/.*)?
exim_spool_t
/var/spool/exim[0-9]?(/.*)?
fusefs_t
/var/run/user/[^/]*/gvfs
logwatch_cache_t
/var/lib/epylog(/.*)?
/var/lib/logcheck(/.*)?
/var/cache/logwatch(/.*)?
mail_spool_t
/var/mail(/.*)?
/var/spool/imap(/.*)?
/var/spool/mail(/.*)?
/var/spool/smtpd(/.*)?
nfs_t
root_t
/sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
/
/initrd
spamass_milter_state_t
/var/lib/spamass-milter(/.*)?
spamc_home_t
/root/.pyzor(/.*)?
/root/.razor(/.*)?
/root/.spamd(/.*)?
/root/.spamassassin(/.*)?
/home/[^/]+/.pyzor(/.*)?
/home/[^/]+/.razor(/.*)?
/home/[^/]+/.spamd(/.*)?
/home/[^/]+/.spamassassin(/.*)?
spamd_compiled_t
/var/lib/spamassassin/compiled(/.*)?
spamd_etc_t
/etc/pyzor(/.*)?
/etc/razor(/.*)?
spamd_log_t
/var/log/spamd.log.*
/var/log/mimedefang.*
/var/log/pyzord.log.*
/var/log/razor-agent.log.*
spamd_spool_t
/var/spool/spamd(/.*)?
/var/spool/spampd(/.*)?
/var/spool/spamassassin(/.*)?
spamd_tmp_t
spamd_var_lib_t
/var/lib/razor(/.*)?
/var/lib/pyzord(/.*)?
/var/lib/spamassassin(/.*)?
spamd_var_run_t
/var/run/spamassassin(/.*)?
/var/spool/MIMEDefang(/.*)?
/var/spool/MD-Quarantine(/.*)?
user_home_t
/home/[^/]+/.+
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 spamd policy is very flexible allowing users to setup their spamd processes in as secure a method as possible.
EQUIVALENCE DIRECTORIES
spamd policy stores data with multiple different file context types under the /var/lib/spamassassin directory. If you would like to store the data in a different directory you can use the semanage command to create an equivalence mapping. If you wanted to store this data under the /srv dirctory you would execute the following command:
semanage fcontext -a -e /var/lib/spamassassin /srv/spamassassin
restorecon -R -v /srv/spamassassin
STANDARD FILE CONTEXT
SELinux defines the file context types for the spamd, if you wanted to store files with these types in a diffent paths, you need to execute the semanage command to sepecify alternate labeling and then use restorecon to put the labels on disk.
semanage fcontext -a -t spamd_etc_t '/srv/myspamd_content(/.*)?'
restorecon -R -v /srv/myspamd_content
Note: SELinux often uses regular expressions to specify labels that match multiple files.
The following file types are defined for spamd:
spamd_compiled_t
- Set files with the spamd_compiled_t type, if you want to treat the files as spamd compiled data.
spamd_etc_t
- Set files with the spamd_etc_t type, if you want to store spamd files in the /etc directories.
spamd_exec_t
- Set files with the spamd_exec_t type, if you want to transition an executable to the spamd_t domain.
spamd_initrc_exec_t
- Set files with the spamd_initrc_exec_t type, if you want to transition an executable to the spamd_initrc_t domain.
spamd_log_t
- Set files with the spamd_log_t type, if you want to treat the data as spamd log data, usually stored under the /var/log directory.
spamd_spool_t
- Set files with the spamd_spool_t type, if you want to store the spamd files under the /var/spool directory.
spamd_tmp_t
- Set files with the spamd_tmp_t type, if you want to store spamd temporary files in the /tmp directories.
spamd_update_exec_t
- Set files with the spamd_update_exec_t type, if you want to transition an executable to the spamd_update_t domain.
spamd_var_lib_t
- Set files with the spamd_var_lib_t type, if you want to store the spamd files under the /var/lib directory.
spamd_var_run_t
- Set files with the spamd_var_run_t type, if you want to store the spamd files under the /run or /var/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.
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 port can also be used to manipulate the port definitions
semanage boolean can also be used to manipulate the booleans
system-config-selinux is a GUI tool available to customize SELinux policy settings.