NAME¶

dnsmasq_selinux - Security Enhanced Linux Policy for the dnsmasq processes

DESCRIPTION¶

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

The dnsmasq processes execute with the dnsmasq_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 dnsmasq_t

ENTRYPOINTS¶

The dnsmasq_t SELinux type can be entered via the dnsmasq_exec_t file type.

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

/usr/sbin/dnsmasq

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 dnsmasq policy is very flexible allowing users to setup their dnsmasq processes in as secure a method as possible.

The following process types are defined for dnsmasq:

dnsmasq_t

Note: semanage permissive -a dnsmasq_t can be used to make the process type dnsmasq_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.

BOOLEANS¶

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

If you want to allow all daemons to write corefiles to /, you must turn on the allow_daemons_dump_core boolean. Disabled by default.

setsebool -P allow_daemons_dump_core 1

If you want to allow all daemons to use tcp wrappers, you must turn on the allow_daemons_use_tcp_wrapper boolean. Disabled by default.

setsebool -P allow_daemons_use_tcp_wrapper 1

If you want to allow all daemons the ability to read/write terminals, you must turn on the allow_daemons_use_tty boolean. Disabled by default.

setsebool -P allow_daemons_use_tty 1

If you want to allow all domains to use other domains file descriptors, you must turn on the allow_domain_fd_use boolean. Enabled by default.

setsebool -P allow_domain_fd_use 1

If you want to allow confined applications to run with kerberos, you must turn on the allow_kerberos boolean. Enabled by default.

setsebool -P allow_kerberos 1

If you want to allow sysadm to debug or ptrace all processes, you must turn on the allow_ptrace boolean. Disabled by default.

setsebool -P allow_ptrace 1

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

setsebool -P allow_ypbind 1

If you want to enable cluster mode for daemons, you must turn on the daemons_enable_cluster_mode boolean. Disabled by default.

setsebool -P daemons_enable_cluster_mode 1

If you want to allow all domains to have the kernel load modules, you must turn on the domain_kernel_load_modules boolean. Disabled by default.

setsebool -P domain_kernel_load_modules 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 enable reading of urandom for all domains, you must turn on the global_ssp boolean. Disabled by default.

setsebool -P global_ssp 1

If you want to enable support for upstart as the init program, you must turn on the init_upstart boolean. Enabled by default.

setsebool -P init_upstart 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

MANAGED FILES¶

The SELinux process type dnsmasq_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(64)?/openais(/.*)?
/var/lib(64)?/pengine(/.*)?
/var/lib(64)?/corosync(/.*)?
/usr/lib(64)?/heartbeat(/.*)?
/var/lib(64)?/heartbeat(/.*)?
/var/lib(64)?/pacemaker(/.*)?
/var/lib/cluster(/.*)?

cluster_var_run_t

/var/run/crm(/.*)?
/var/run/cman_.*
/var/run/rsctmp(/.*)?
/var/run/aisexec.*
/var/run/heartbeat(/.*)?
/var/run/cpglockd.pid
/var/run/corosync.pid
/var/run/rgmanager.pid
/var/run/cluster/rgmanager.sk

crond_var_run_t

/var/run/crond?.pid
/var/run/crond?.reboot
/var/run/atd.pid
/var/run/fcron.pid
/var/run/fcron.fifo
/var/run/anacron.pid

dnsmasq_lease_t

/var/lib/dnsmasq(/.*)?
/var/lib/misc/dnsmasq.leases

dnsmasq_var_log_t

/var/log/dnsmasq.log.*

dnsmasq_var_run_t

/var/run/libvirt/network(/.*)?
/var/run/dnsmasq.pid

initrc_tmp_t

mnt_t

/mnt(/[^/]*)
/mnt(/[^/]*)?
/rhev(/[^/]*)?
/media(/[^/]*)
/media(/[^/]*)?
/etc/rhgb(/.*)?
/media/.hal-.*
/net
/afs
/rhev
/misc

neutron_var_lib_t

/var/lib/quantum(/.*)?
/var/lib/neutron(/.*)?

root_t

/
/initrd

tmp_t

/tmp
/usr/tmp
/var/tmp
/tmp-inst
/var/tmp-inst
/var/tmp/vi.recover

virt_var_lib_t

/var/lib/oz(/.*)?
/var/lib/libvirt(/.*)?

virt_var_run_t

/var/vdsm(/.*)?
/var/run/vdsm(/.*)?
/var/run/libvirt(/.*)?

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 dnsmasq policy is very flexible allowing users to setup their dnsmasq processes in as secure a method as possible.

STANDARD FILE CONTEXT

SELinux defines the file context types for the dnsmasq, 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 dnsmasq_var_run_t '/srv/mydnsmasq_content(/.*)?'
restorecon -R -v /srv/mydnsmasq_content

Note: SELinux often uses regular expressions to specify labels that match multiple files.

The following file types are defined for dnsmasq:

dnsmasq_etc_t

- Set files with the dnsmasq_etc_t type, if you want to store dnsmasq files in the /etc directories.

dnsmasq_exec_t

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

dnsmasq_initrc_exec_t

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

dnsmasq_lease_t

- Set files with the dnsmasq_lease_t type, if you want to treat the files as dnsmasq lease data.

Paths:

/var/lib/dnsmasq(/.*)?, /var/lib/misc/dnsmasq.leases

dnsmasq_var_log_t

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

dnsmasq_var_run_t

- Set files with the dnsmasq_var_run_t type, if you want to store the dnsmasq files under the /run or /var/run directory.

Paths:

/var/run/libvirt/network(/.*)?, /var/run/dnsmasq.pid

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.

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 .

SEE ALSO¶

selinux(8), dnsmasq(8), semanage(8), restorecon(8), chcon(1) , setsebool(8)