secmodel_extensions(9)
- NetBSD Manual Pages
SECMODEL_EXTENSIONS(9) NetBSD Kernel Developer's Manual SECMODEL_EXTENSIONS(9)
NAME
secmodel_extensions -- extensions security model
DESCRIPTION
secmodel_extensions implements extensions to the traditional security
model based on the original 4.4BSD. They can be used to grant additional
privileges to ordinary users, or enable specific security measures like
curtain mode.
The extensions are described below.
Curtain mode
When enabled, all returned objects will be filtered according to the
user-id requesting information about them, preventing users from access-
ing objects they do not own.
It affects the output of many commands, including fstat(1), netstat(1),
ps(1), sockstat(1), and w(1).
This extension is enabled by setting security.models.extensions.curtain
or security.curtain sysctl(7) to a non-zero value.
It can be enabled at any time, but cannot be disabled anymore when the
securelevel of the system is above 0.
Non-superuser mounts
When enabled, it allows file-systems to be mounted by an ordinary user
who owns the point node and has at least read access to the special
device mount(8) arguments. Note that the nosuid and nodev flags must be
given for non-superuser mounts.
This extension is enabled by setting security.models.extensions.usermount
or vfs.generic.usermount sysctl(7) to a non-zero value.
It can be disabled at any time, but cannot be enabled anymore when the
securelevel of the system is above 0.
Non-superuser control of CPU sets
When enabled, an ordinary user is allowed to control the CPU affinity(3)
of the processes and threads they own.
This extension is enabled by setting
security.models.extensions.user_set_cpu_affinity sysctl(7) to a non-zero
value.
It can be disabled at any time, but cannot be enabled anymore when the
securelevel of the system is above 0.
Hardlink restrictions
Prevent hardlinks to files that the user does not own or has group access
to.
To enable user ownership checks, set the sysctl(7) variable
security.models.extensions.hardlink_check_uid to a non-zero value.
To enable group membership checks, set the sysctl(7) variable
security.models.extensions.hardlink_check_gid to a non-zero value.
These variables can be enabled anytime, but cannot be disabled anymore
when the securelevel of the system is above 0.
SEE ALSO
affinity(3), sched(3), sysctl(7), kauth(9), secmodel(9),
secmodel_bsd44(9), secmodel_securelevel(9), secmodel_suser(9)
AUTHORS
Elad Efrat <elad@NetBSD.org>
NetBSD 10.99 March 27, 2022 NetBSD 10.99
Powered by man-cgi (2021-06-01).
Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.