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.

4 files changed, 147 insertions, 4 deletions

diff --git a/tests/cp/cp-a-selinux.sh b/tests/cp/cp-a-selinux.sh
index e7bdcf1df..ac7bf1c3a 100755
--- a/tests/cp/cp-a-selinux.sh
+++ b/tests/cp/cp-a-selinux.sh
@@ -1,5 +1,5 @@
 #!/bin/sh
-# Ensure that cp -a and cp --preserve=context work properly.
+# Ensure that cp -Z, -a and cp --preserve=context work properly.
 # In particular, test on a writable NFS partition.
 # Check also locally if --preserve=context, -a and --preserve=all
 # does work
@@ -41,6 +41,45 @@ test -s err && fail=1   #there must be no stderr output for -a
 ls -Z e | grep $ctx || fail=1
 ls -Z f | grep $ctx || fail=1
 
+# Check restorecon (-Z) functionality for file and directory
+get_selinux_type() { ls -Zd "$1" | sed -n 's/.*:\(.*_t\):.*/\1/p'; }
+# Also make a dir with our known context
+mkdir c_d || framework_failure_
+chcon $ctx c_d || framework_failure_
+# Get the type of this known context for file and dir
+old_type_f=$(get_selinux_type c)
+old_type_d=$(get_selinux_type c_d)
+# Setup copies for manipulation with restorecon
+# and get the adjusted type for comparison
+cp -a c Z1 || fail=1
+cp -a c_d Z1_d || fail=1
+if restorecon Z1 Z1_d 2>/dev/null; then
+  new_type_f=$(get_selinux_type Z1)
+  new_type_d=$(get_selinux_type Z1_d)
+
+  # Ensure -Z sets the type like restorecon does
+  cp -Z c Z2 || fail=1
+  cpZ_type_f=$(get_selinux_type Z2)
+  test "$cpZ_type_f" = "$new_type_f" || fail=1
+
+  # Ensuze -Z overrides -a and that dirs are handled too
+  cp -aZ c Z3 || fail=1
+  cp -aZ c_d Z3_d || fail=1
+  cpaZ_type_f=$(get_selinux_type Z3)
+  cpaZ_type_d=$(get_selinux_type Z3_d)
+  test "$cpaZ_type_f" = "$new_type_f" || fail=1
+  test "$cpaZ_type_d" = "$new_type_d" || fail=1
+
+  # Ensure -Z sets the type for existing files
+  mkdir -p existing/c_d || framework_failure_
+  touch existing/c || framework_failure_
+  cp -aZ c c_d existing || fail=1
+  cpaZ_type_f=$(get_selinux_type existing/c)
+  cpaZ_type_d=$(get_selinux_type existing/c_d)
+  test "$cpaZ_type_f" = "$new_type_f" || fail=1
+  test "$cpaZ_type_d" = "$new_type_d" || fail=1
+fi
+
 skip=0
 # Create a file system, then mount it with the context=... option.
 dd if=/dev/zero of=blob bs=8192 count=200    || skip=1
@@ -97,7 +136,7 @@ echo > g
 cp --preserve=context f g 2> out && fail=1
 # Here, we *do* expect the destination to be empty.
 test -s g && fail=1
-sed "s/ .g' to .*//" out > k
+sed "s/ .g'.*//" out > k
 mv k out
 compare exp out || fail=1
 
@@ -107,8 +146,39 @@ echo > g
 cp -a --preserve=context f g 2> out2 && fail=1
 # Here, we *do* expect the destination to be empty.
 test -s g && fail=1
-sed "s/ .g' to .*//" out2 > k
+sed "s/ .g'.*//" out2 > k
 mv k out2
 compare exp out2 || fail=1
 
+for no_g_cmd in '' 'rm -f g'; do
+  # restorecon equivalent.  Note even though the context
+  # returned from matchpathcon() will not match $ctx
+  # the resulting ENOTSUP warning will be suppressed.
+   # With absolute path
+  $no_g_cmd
+  cp -Z f $(realpath g) || fail=1
+   # With relative path
+  $no_g_cmd
+  cp -Z f g || fail=1
+   # -Z overrides -a
+  $no_g_cmd
+  cp -Z -a f g || fail=1
+   # -Z doesn't take an arg
+  $no_g_cmd
+  cp -Z "$ctx" f g && fail=1
+
+  # Explicit context
+  $no_g_cmd
+   # Explicitly defaulting to the global $ctx should work
+  cp --context="$ctx" f g || fail=1
+   # --context overrides -a
+  $no_g_cmd
+  cp -a --context="$ctx" f g || fail=1
+done
+
+# Mutually exlusive options
+cp -Z --preserve=context f g && fail=1
+cp --preserve=context -Z f g && fail=1
+cp --preserve=context --context="$ctx" f g && fail=1
+
 Exit $fail
diff --git a/tests/local.mk b/tests/local.mk
index 2dd7e2063..19bbbd7d2 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -567,6 +567,7 @@ all_tests =					\
   tests/mkdir/parents.sh			\
   tests/mkdir/perm.sh				\
   tests/mkdir/selinux.sh			\
+  tests/mkdir/restorecon.sh			\
   tests/mkdir/special-1.sh			\
   tests/mkdir/t-slash.sh			\
   tests/mv/acl.sh				\
diff --git a/tests/mkdir/restorecon.sh b/tests/mkdir/restorecon.sh
new file mode 100755
index 000000000..01a647736
--- /dev/null
+++ b/tests/mkdir/restorecon.sh
@@ -0,0 +1,72 @@
+#!/bin/sh
+# test mkdir, mknod, mkfifo -Z
+
+# Copyright (C) 2013 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ mkdir
+require_selinux_
+
+
+get_selinux_type() { ls -Zd "$1" | sed -n 's/.*:\(.*_t\):.*/\1/p'; }
+
+mkdir subdir || framework_failure_
+chcon 'root:object_r:tmp_t:s0' subdir || framework_failure_
+cd subdir
+
+# --- mkdir -Z ---
+# Since in a tmp_t dir, dirs can be created as user_tmp_t ...
+mkdir standard || framework_failure_
+mkdir restored || framework_failure_
+if restorecon restored 2>/dev/null; then
+  # ... but when restored can be set to user_home_t
+  # So ensure the type for these mkdir -Z cases matches
+  # the directory type as set by restorecon.
+  mkdir -Z single || fail=1
+  # Run these as separate processes in case global context
+  # set for an arg, impacts on another arg
+  for dir in single_p single_p/existing multi/ple; do
+    mkdir -Zp "$dir" || fail=1
+  done
+  restored_type=$(get_selinux_type 'restored')
+  test "$(get_selinux_type 'single')" = "$restored_type" || fail=1
+  test "$(get_selinux_type 'single_p')" = "$restored_type" || fail=1
+  test "$(get_selinux_type 'single_p/existing')" = "$restored_type" || fail=1
+  test "$(get_selinux_type 'multi')" = "$restored_type" || fail=1
+  test "$(get_selinux_type 'multi/ple')" = "$restored_type" || fail=1
+fi
+if test "$fail" = '1'; then
+  ls -UZd standard restored
+  ls -UZd single single_p single_p/existing multi multi/ple
+fi
+
+# --- mknod -Z and mkfifo -Z ---
+# Assume if selinux present that we can create fifos
+for cmd_w_arg in 'mknod' 'mkfifo'; do
+  # In OpenBSD's /bin/sh, mknod is a shell built-in.
+  # Running via "env" ensures we run our program and not the built-in.
+  basename="$cmd_w_arg"
+  test "$basename" = 'mknod' && nt='p' || nt=''
+  env -- $cmd_w_arg $basename $nt || fail=1
+  env -- $cmd_w_arg ${basename}_restore $nt || fail=1
+  if restorecon ${basename}_restore 2>/dev/null; then
+    env -- $cmd_w_arg -Z ${basename}_Z $nt || fail=1
+    restored_type=$(get_selinux_type "${basename}_restore")
+    test "$(get_selinux_type ${basename}_Z)" = "$restored_type" || fail=1
+  fi
+done
+
+Exit $fail
diff --git a/tests/mkdir/selinux.sh b/tests/mkdir/selinux.sh
index e68f77b87..c1cfaf05e 100755
--- a/tests/mkdir/selinux.sh
+++ b/tests/mkdir/selinux.sh
@@ -32,7 +32,7 @@ msg="failed to set default file creation context to '$c':"
 for cmd_w_arg in 'mkdir dir' 'mknod b p' 'mkfifo f'; do
   # In OpenBSD's /bin/sh, mknod is a shell built-in.
   # Running via "env" ensures we run our program and not the built-in.
-  env -- $cmd_w_arg -Z $c 2> out && fail=1
+  env -- $cmd_w_arg --context=$c 2> out && fail=1
   set $cmd_w_arg; cmd=$1
   echo "$cmd: $msg" > exp || fail=1