selinux_restorecon(3) SELinux API documentation selinux_restorecon(3)
NAME
selinux_restorecon - restore file(s) default SELinux security contexts
SYNOPSIS
#include <selinux/restorecon.h>
int selinux_restorecon(const char *pathname,
unsigned int restorecon_flags);
DESCRIPTION
selinux_restorecon() restores file default security contexts on
filesystems that support extended attributes (see xattr(7)), based on:
pathname containing a directory or file to be relabeled.
If this is a directory and the restorecon_flags SELINUX_RESTORE-
CON_RECURSE has been set (for descending through directories),
then selinux_restorecon() will write an SHA1 digest of the com-
bined specfiles (see the NOTES section for details) to an
extended attribute of security.restorecon_last once the relabel-
ing has been completed successfully. This digest will be checked
should selinux_restorecon() be rerun with the restorecon_flags
SELINUX_RESTORECON_RECURSE flag set. If any of the specfiles had
been updated, the digest will also be updated. However if the
digest is the same, no relabeling checks will take place (unless
the SELINUX_RESTORECON_IGNORE_DIGEST flag is set).
restorecon_flags contains the labeling option/rules as follows:
SELINUX_RESTORECON_IGNORE_DIGEST force the checking of
labels even if the stored SHA1 digest matches the spec-
files SHA1 digest. The specfiles digest will be written
to the security.restorecon_last extended attribute once
relabeling has been completed successfully provided the
SELINUX_RESTORECON_NOCHANGE flag has not been set.
SELINUX_RESTORECON_NOCHANGE don't change any file labels
(passive check) or update the digest in the secu-
rity.restorecon_last extended attribute.
SELINUX_RESTORECON_SET_SPECFILE_CTX If set, reset the
files label to match the default specfile context. If
not set only reset the files "type" component of the con-
text to match the default specfile context.
SELINUX_RESTORECON_RECURSE change file and directory
labels recursively (descend directories) and if success-
ful write an SHA1 digest of the combined specfiles to an
extended attribute as described in the NOTES section.
SELINUX_RESTORECON_VERBOSE log file label changes.
Note that if SELINUX_RESTORECON_VERBOSE and
SELINUX_RESTORECON_PROGRESS flags are set, then
SELINUX_RESTORECON_PROGRESS will take precedence.
SELINUX_RESTORECON_PROGRESS show progress by outputting
the number of files in 1k blocks processed to stdout. If
the SELINUX_RESTORECON_MASS_RELABEL flag is also set then
the approximate percentage complete will be shown.
SELINUX_RESTORECON_MASS_RELABEL generally set when rela-
beling the entire OS, that will then show the approximate
percentage complete. The SELINUX_RESTORECON_PROGRESS flag
must also be set.
SELINUX_RESTORECON_REALPATH convert passed-in pathname to
the canonical pathname using realpath(3).
SELINUX_RESTORECON_XDEV prevent descending into directo-
ries that have a different device number than the path-
name entry from which the descent began.
SELINUX_RESTORECON_ADD_ASSOC attempt to add an associa-
tion between an inode and a specification. If there is
already an association for the inode and it conflicts
with the specification, then use the last matching speci-
fication.
SELINUX_RESTORECON_ABORT_ON_ERROR abort on errors during
the file tree walk.
SELINUX_RESTORECON_SYSLOG_CHANGES log any label changes
to syslog(3).
SELINUX_RESTORECON_LOG_MATCHES log what specfile context
matched each file.
SELINUX_RESTORECON_IGNORE_NOENTRY ignore files that do
not exist.
SELINUX_RESTORECON_IGNORE_MOUNTS do not read /proc/mounts
to obtain a list of non-seclabel mounts to be excluded
from relabeling checks.
Setting SELINUX_RESTORECON_IGNORE_MOUNTS is useful where
there is a non-seclabel fs mounted with a seclabel fs
mounted on a directory below this.
The behavior regarding the checking and updating of the SHA1
digest described above is the default behavior. It is possible
to change this by first calling selabel_open(3) and not enabling
the SELABEL_OPT_DIGEST option, then calling selinux_restore-
con_set_sehandle(3) to set the handle to be used by
selinux_restorecon(3).
If the pathname is a directory path, then it is possible to set
directories to be excluded from the path by calling
selinux_restorecon_set_exclude_list(3) with a NULL terminated
list before calling selinux_restorecon(3).
By default selinux_restorecon(3) reads /proc/mounts to obtain a
list of non-seclabel mounts to be excluded from relabeling
checks unless the SELINUX_RESTORECON_IGNORE_MOUNTS flag has been
set.
RETURN VALUE
On success, zero is returned. On error, -1 is returned and errno is
set appropriately.
NOTES
1. To improve performance when relabeling file systems recursively
(e.g. the restorecon_flags SELINUX_RESTORECON_RECURSE flag is set)
selinux_restorecon() will write an SHA1 digest of the specfiles
that are processed by selabel_open(3) to an extended attribute
named security.restorecon_last to the directory specified in the
pathname.
2. To check the extended attribute entry use getfattr(1), for example:
getfattr -e hex -n security.restorecon_last /
3. The SHA1 digest is calculated by selabel_open(3) concatenating the
specfiles it reads during initialisation with the resulting digest
and list of specfiles being retrieved by selabel_digest(3).
4. The specfiles consist of the mandatory file_contexts file plus any
subs, subs_dist, local and homedir entries (text or binary ver-
sions) as determined by any selabel_open(3) options e.g. SELA-
BEL_OPT_BASEONLY.
Should any of the specfiles have changed, then when
selinux_restorecon() is run again with the SELINUX_RESTORE-
CON_RECURSE flag set, a new SHA1 digest will be calculated and all
files will be automatically relabeled depending on the settings of
the SELINUX_RESTORECON_SET_SPECFILE_CTX flag (provided
SELINUX_RESTORECON_NOCHANGE is not set).
5. /sys and in-memory filesystems do not support the security.restore-
con_last extended attribute and are automatically excluded from any
relabeling checks.
6. By default stderr is used to log output messages and errors. This
may be changed by calling selinux_set_callback(3) with the
SELINUX_CB_LOG type option.
SEE ALSO
selinux_restorecon_set_sehandle(3),
selinux_restorecon_default_handle(3),
selinux_restorecon_set_exclude_list(3),
selinux_restorecon_set_alt_rootpath(3),
selinux_restorecon_xattr(3),
selinux_set_callback(3)
Security Enhanced Linux 20 Oct 2015 selinux_restorecon(3)
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