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MAC_NTPD(4)		     Kernel Interfaces Manual		     MAC_NTPD(4)

NAME
     mac_ntpd -- policy allowing ntpd to run as non-root user

SYNOPSIS
     To compile the ntpd policy into your kernel, place the following lines in
     your kernel configuration file:

	   options MAC
	   options MAC_NTPD

     Alternately, to load the ntpd policy module at boot time, place the
     following line in your kernel configuration file:

	   options MAC

     and in loader.conf(5):

	   mac_ntpd_load="YES"

DESCRIPTION
     The mac_ntpd policy grants any process running as user `ntpd' (uid 123) the
     privileges needed to manipulate system time, and to (re-)bind to the privi-
     leged NTP port.

     When  ntpd(8)  is	started with `-u <user>[:group]' on the command line, it
     performs all initializations requiring root  privileges,  then  drops  root
     privileges by switching to the given user id.  From that point on, the only
     privileges  it  requires are the ability to manipulate system time, and the
     ability to re-bind a UDP socket to the NTP port (port 123) after a  network
     interface change.

     With the mac_ntpd policy active, it may also be possible to start ntpd as a
     non-root  user,  because  the  default ntpd options don't require any addi-
     tional root privileges beyond those granted by the policy.

   Privileges Granted
     The exact set of kernel privileges granted to any process running with  the
     configured uid is:
	   PRIV_ADJTIME
	   PRIV_CLOCK_SETTIME
	   PRIV_NTP_ADJTIME
	   PRIV_NETINET_RESERVEDPORT
	   PRIV_NETINET_REUSEPORT

   Runtime Configuration
     The following sysctl(8) MIBs are available for fine-tuning this MAC policy.
     All   sysctl(8)  variables  can  also  be	set  as  loader(8)  tunables  in
     loader.conf(5).

     security.mac.ntpd.enabled
	     Enable the mac_ntpd policy.  (Default: 1).

     security.mac.ntpd.uid
	     The numeric uid of the ntpd user.	(Default: 123).

SEE ALSO
     mac(4), ntpd(8)

HISTORY
     MAC  first  appeared  in  FreeBSD	5.0  and  mac_ntpd  first  appeared   in
     FreeBSD 12.0.

FreeBSD ports 15.1		  July 20, 2018 		     MAC_NTPD(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=mac_ntpd&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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