selinux: adjust utils to run restorecon with -Z

cp, mv, install, mkdir, mkfifo, mknod are adjusted so that:
 -Z no longer accepts an argument.
 -Z or --context without an argument do not warn without SELinux.
 --context with an argument will warn without SELinux.

* src/local.mk: Reference the new selinux module where required.
* src/system.h: Make the argument to --context optional.
* src/mkdir.c: Likewise.  Also handle the SMACK case for --context.
Note we currently silently ignore -Z with SMACK.
* src/mkfifo.c: Likewise.
* src/mknod.c: Likewise.
* src/install.c: Likewise.  Note install(1) by default already
set the context for target files to their system default,
albeit with an older method.  Use the -Z option to select between
the old and new context restoration behavior, and document
the differences and details for how context restoration
is done in new and old methods, with a view disabling the
old method entirely in future.
* src/cp.c: Make the argument to --context optional.
Note -Z implies --no-preserve=context.  I.E. -Z overrides
that aspect of -a no matter what order specified.
(struct cp_options): Document the context handling options.
(main): Check/adjust option combinations after all
options are processed, to both simplify processing
and to make handling independent of order of options
on the command line.  Also improve the diagnostics
from a failed call to setfscreatecon().
(set_process_security_ctx): A new function,
refactored to set the default context from the source file,
or with the type adjusted as per the system default for
the destination path.
(set_file_security_ctx): A new function refactored to
set the security context of an existing file, either based on
the process context or the default system context for a path.
(copy_internal): Use the refactored functions to simplify
error handling and consistently fail or warn as needed.
(copy_reg): Likewise.
(copy_internal): With --preserve=context, also copy
context from non regular files.  Note for directories this may
impact the copying of subsequent files to that directory?
(copy_attr): If we're handling SELinux explicitly,
then exclude to avoid the redudant copy with --preserve=context,
and the problematic copy with -Z.  Note SELinux attribute exclusion
also now honors cp -a --no-preserve=context.  Note there was a
very small window over 10 years ago, where attr_copy_file was
available, while attr_copy_check_permissions was not, so we
don't bother adding an explicit m4 check for the latter function.
* src/mv.c: Support --context, but don't allow specifying an argument.
* src/chcon.c: Adjust a comment to be specific to SELinux.
* src/runcon.c: Likewise.
* src/copy.c: Honor the context settings to "restorecon" as appropriate.
* src/copy.h: Add a new setting to select "restorecon" functionality.
* tests/mkdir/selinux.sh: s/-Z/--context=/
* tests/cp/cp-a-selinux.sh: Augment this test with cases
testing basic -Z functionality, and also test the various
invalid option combinations and option precedence.
* tests/mkdir/restorecon.sh: Add a new test for the
more involved mkdir -Z handling, since the directory changing
and non existent directories need to be specially handled.
Also check the similar but simpler handling of -Z by mk{nod,fifo}.
* tests/local.mk: Reference the new test.
* doc/coreutils.texi (cp invocation): Update as per interface changes.
(mv invocation): Likewise.
(install invocation): Likewise.
(mkfifo invocation): Likewise.
(mknod invocation): Likewise.
(mkdir invocation): Likewise.
* NEWS: Mention the new feature and change in behavior.

1 files changed, 12 insertions, 4 deletions

diff --git a/src/local.mk b/src/local.mk
index 646fbada1..1315e1103 100644
--- a/src/local.mk
+++ b/src/local.mk
@@ -312,6 +312,10 @@ RELEASE_YEAR = \
   `sed -n '/.*COPYRIGHT_YEAR = \([0-9][0-9][0-9][0-9]\) };/s//\1/p' \
     $(top_srcdir)/lib/version-etc.c`
 
+selinux_sources = \
+  src/selinux.c \
+  src/selinux.h
+
 copy_sources = \
   src/copy.c \
   src/cp-hash.c \
@@ -323,12 +327,13 @@ copy_sources = \
 # to install before applying any user-specified name transformations.
 
 transform = s/ginstall/install/; $(program_transform_name)
-src_ginstall_SOURCES = src/install.c src/prog-fprintf.c $(copy_sources)
+src_ginstall_SOURCES = src/install.c src/prog-fprintf.c $(copy_sources) \
+		       $(selinux_sources)
 
 # This is for the '[' program.  Automake transliterates '[' and '/' to '_'.
 src___SOURCES = src/lbracket.c
 
-src_cp_SOURCES = src/cp.c $(copy_sources)
+src_cp_SOURCES = src/cp.c $(copy_sources) $(selinux_sources)
 src_dir_SOURCES = src/ls.c src/ls-dir.c
 src_vdir_SOURCES = src/ls.c src/ls-vdir.c
 src_id_SOURCES = src/id.c src/group-list.c
@@ -341,12 +346,15 @@ src_kill_SOURCES = src/kill.c src/operand2sig.c
 src_realpath_SOURCES = src/realpath.c src/relpath.c src/relpath.h
 src_timeout_SOURCES = src/timeout.c src/operand2sig.c
 
-src_mv_SOURCES = src/mv.c src/remove.c $(copy_sources)
+src_mv_SOURCES = src/mv.c src/remove.c $(copy_sources) $(selinux_sources)
 src_rm_SOURCES = src/rm.c src/remove.c
 
-src_mkdir_SOURCES = src/mkdir.c src/prog-fprintf.c
+src_mkdir_SOURCES = src/mkdir.c src/prog-fprintf.c $(selinux_sources)
 src_rmdir_SOURCES = src/rmdir.c src/prog-fprintf.c
 
+src_mkfifo_SOURCES = src/mkfifo.c $(selinux_sources)
+src_mknod_SOURCES = src/mknod.c $(selinux_sources)
+
 src_df_SOURCES = src/df.c src/find-mount-point.c
 src_stat_SOURCES = src/stat.c src/find-mount-point.c