Security-Enhanced Linux secures the mysqld processes via flexible mandatory access control.
The mysqld processes execute with the mysqld_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 mysqld_t
The mysqld_t SELinux type can be entered via the mysqld_exec_t file type.
The default entrypoint paths for the mysqld_t domain are the following:
/usr/sbin/mysqld(-max|-debug)?, /usr/sbin/ndbd, /usr/libexec/mysqld, /usr/bin/mysql_upgrade, /usr/bin/mysqld_safe_helper
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux mysqld policy is very flexible allowing users to setup their mysqld processes in as secure a method as possible.
The following process types are defined for mysqld:
mysqld_t, mysqld_safe_t
Note: semanage permissive -a mysqld_t can be used to make the process type mysqld_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 mysqld to connect to all ports, you must turn on the mysql_connect_any boolean. Disabled by default.
setsebool -P mysql_connect_any 1
If you want to allow mysqld to connect to http port, you must turn on the mysql_connect_http boolean. Disabled by default.
setsebool -P mysql_connect_http 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 determine whether exim can connect to databases, you must turn on the exim_can_connect_db boolean. Disabled by default.
setsebool -P exim_can_connect_db 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 determine whether ftpd can connect to databases over the TCP network, you must turn on the ftpd_connect_db boolean. Disabled by default.
setsebool -P ftpd_connect_db 1
If you want to allow HTTPD scripts and modules to connect to databases over the network, you must turn on the httpd_can_network_connect_db boolean. Disabled by default.
setsebool -P httpd_can_network_connect_db 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
If you want to allow PowerDNS to connect to databases over the network, you must turn on the pdns_can_network_connect_db boolean. Disabled by default.
setsebool -P pdns_can_network_connect_db 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 mysqld policy is very flexible allowing users to setup their mysqld processes in as secure a method as possible.
The following port types are defined for mysqld:
Default Defined Ports: tcp 1186,3306,63132-63164
The SELinux process type mysqld_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.
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
faillog_t
/var/log/btmp.*
/var/log/faillog.*
/var/log/tallylog.*
/var/run/faillock(/.*)?
hugetlbfs_t
/dev/hugepages
/usr/lib/udev/devices/hugepages
krb5_host_rcache_t
/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
lastlog_t
/var/log/lastlog.*
mysqld_db_t
/var/lib/mysql(-files|-keyring)?(/.*)?
mysqld_log_t
/var/log/mysql.*
/var/log/mysql(/.*)?
/var/log/mariadb(/.*)?
mysqld_tmp_t
mysqld_var_run_t
/var/run/mysqld(/.*)?
/var/run/mariadb(/.*)?
/var/lib/mysql/mysql.sock
root_t
/sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
/
/initrd
security_t
/selinux
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 mysqld policy is very flexible allowing users to setup their mysqld processes in as secure a method as possible.
EQUIVALENCE DIRECTORIES
mysqld policy stores data with multiple different file context types under the /var/log/mysql 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/log/mysql /srv/mysql
restorecon -R -v /srv/mysql
STANDARD FILE CONTEXT
SELinux defines the file context types for the mysqld, 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 mysqld_tmp_t '/srv/mymysqld_content(/.*)?'
restorecon -R -v /srv/mymysqld_content
Note: SELinux often uses regular expressions to specify labels that match multiple files.
The following file types are defined for mysqld:
mysqld_db_t
- Set files with the mysqld_db_t type, if you want to treat the files as mysqld database content.
mysqld_etc_t
- Set files with the mysqld_etc_t type, if you want to store mysqld files in the /etc directories.
mysqld_exec_t
- Set files with the mysqld_exec_t type, if you want to transition an executable to the mysqld_t domain.
mysqld_home_t
- Set files with the mysqld_home_t type, if you want to store mysqld files in the users home directory.
mysqld_initrc_exec_t
- Set files with the mysqld_initrc_exec_t type, if you want to transition an executable to the mysqld_initrc_t domain.
mysqld_log_t
- Set files with the mysqld_log_t type, if you want to treat the data as mysqld log data, usually stored under the /var/log directory.
mysqld_safe_exec_t
- Set files with the mysqld_safe_exec_t type, if you want to transition an executable to the mysqld_safe_t domain.
mysqld_tmp_t
- Set files with the mysqld_tmp_t type, if you want to store mysqld temporary files in the /tmp directories.
mysqld_unit_file_t
- Set files with the mysqld_unit_file_t type, if you want to treat the files as mysqld unit content.
mysqld_var_run_t
- Set files with the mysqld_var_run_t type, if you want to store the mysqld 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.