commit:     7c30c8834c281dc9a151d1d11f68aac9d86067b1
Author:     Guido Trentalancia <guido <AT> trentalancia <DOT> net>
AuthorDate: Fri Dec 23 00:22:39 2016 +0000
Commit:     Jason Zaman <perfinion <AT> gentoo <DOT> org>
CommitDate: Sun Jan  1 16:26:28 2017 +0000
URL:        
https://gitweb.gentoo.org/proj/hardened-refpolicy.git/commit/?id=7c30c883

bootloader: stricter permissions and more tailored file contexts

Update the bootloader module so that it can manage only its
own runtime files and not all boot_t files (which include,
for example, the common locations for kernel images and
initramfs archives) and so that it can execute only its own
etc files (needed by grub2-mkconfig) and not all etc_t files
which is more dangerous.

Signed-off-by: Guido Trentalancia <guido <AT> trentalancia.net>

 policy/modules/admin/bootloader.fc |  6 ++++++
 policy/modules/admin/bootloader.te | 17 +++++++++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/policy/modules/admin/bootloader.fc 
b/policy/modules/admin/bootloader.fc
index d908d56..5b67c16 100644
--- a/policy/modules/admin/bootloader.fc
+++ b/policy/modules/admin/bootloader.fc
@@ -1,6 +1,12 @@
+/boot/grub.*   -d      gen_context(system_u:object_r:bootloader_run_t,s0)
+/boot/grub.*/.*                
gen_context(system_u:object_r:bootloader_run_t,s0)
+
+/boot/grub.*/grub.cfg  --      
gen_context(system_u:object_r:bootloader_etc_t,s0)
+/boot/grub.*/grub.conf --      
gen_context(system_u:object_r:bootloader_etc_t,s0)
 
 /etc/lilo\.conf.*      --      
gen_context(system_u:object_r:bootloader_etc_t,s0)
 /etc/yaboot\.conf.*    --      
gen_context(system_u:object_r:bootloader_etc_t,s0)
+/etc/grub.d(/.*)?      --      
gen_context(system_u:object_r:bootloader_etc_t,s0)
 
 /sbin/grub             --      
gen_context(system_u:object_r:bootloader_exec_t,s0)
 /sbin/lilo.*           --      
gen_context(system_u:object_r:bootloader_exec_t,s0)

diff --git a/policy/modules/admin/bootloader.te 
b/policy/modules/admin/bootloader.te
index fcaa6d4..e3f2a72 100644
--- a/policy/modules/admin/bootloader.te
+++ b/policy/modules/admin/bootloader.te
@@ -22,6 +22,13 @@ application_domain(bootloader_t, bootloader_exec_t)
 role bootloader_roles types bootloader_t;
 
 #
+# bootloader_run_t are image and other runtime
+# files
+#
+type bootloader_run_t alias run_bootloader_t;
+files_type(bootloader_run_t)
+
+#
 # bootloader_etc_t is the configuration file,
 # grub.conf, lilo.conf, etc.
 #
@@ -45,7 +52,7 @@ allow bootloader_t self:capability { dac_override 
dac_read_search fsetid sys_raw
 allow bootloader_t self:process { signal_perms execmem };
 allow bootloader_t self:fifo_file rw_fifo_file_perms;
 
-allow bootloader_t bootloader_etc_t:file read_file_perms;
+allow bootloader_t bootloader_etc_t:file exec_file_perms;
 # uncomment the following lines if you use "lilo -p"
 #allow bootloader_t bootloader_etc_t:file manage_file_perms;
 #files_etc_filetrans(bootloader_t,bootloader_etc_t,file)
@@ -59,6 +66,11 @@ files_tmp_filetrans(bootloader_t, bootloader_tmp_t, { dir 
file lnk_file chr_file
 # for tune2fs (cjp: ?)
 files_root_filetrans(bootloader_t, bootloader_tmp_t, file)
 
+manage_dirs_pattern(bootloader_t, bootloader_run_t, bootloader_run_t)
+manage_files_pattern(bootloader_t, bootloader_run_t, bootloader_run_t)
+manage_lnk_files_pattern(bootloader_t, bootloader_run_t, bootloader_run_t)
+files_boot_filetrans(bootloader_t, bootloader_run_t, { dir file lnk_file })
+
 kernel_getattr_core_if(bootloader_t)
 kernel_read_network_state(bootloader_t)
 kernel_read_system_state(bootloader_t)
@@ -96,10 +108,7 @@ corecmd_exec_all_executables(bootloader_t)
 domain_use_interactive_fds(bootloader_t)
 
 files_create_boot_dirs(bootloader_t)
-files_manage_boot_files(bootloader_t)
-files_manage_boot_symlinks(bootloader_t)
 files_read_etc_files(bootloader_t)
-files_exec_etc_files(bootloader_t)
 files_read_usr_src_files(bootloader_t)
 files_read_usr_files(bootloader_t)
 files_read_var_files(bootloader_t)

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