Add microdroid specific sepolicy
Microdroid will have a separate sepolicy, apart from the core policy.
This is the first step; For now it's a simple copy of system/sepolicy.
For the future work, it will be stripped.
Bug: 189165759
Test: boot microdroid and see selinux enforced
Change-Id: I2fee39f7231560b49c93bd5e8d0feeffada40938
diff --git a/microdroid/sepolicy/system/public/ueventd.te b/microdroid/sepolicy/system/public/ueventd.te
new file mode 100644
index 0000000..d5d4301
--- /dev/null
+++ b/microdroid/sepolicy/system/public/ueventd.te
@@ -0,0 +1,83 @@
+# ueventd seclabel is specified in init.rc since
+# it lives in the rootfs and has no unique file type.
+type ueventd, domain;
+type ueventd_tmpfs, file_type;
+
+# Write to /dev/kmsg.
+allow ueventd kmsg_device:chr_file rw_file_perms;
+
+allow ueventd self:global_capability_class_set { chown mknod net_admin setgid fsetid sys_rawio dac_override dac_read_search fowner setuid };
+allow ueventd device:file create_file_perms;
+
+r_dir_file(ueventd, rootfs)
+
+# ueventd needs write access to files in /sys to regenerate uevents
+allow ueventd sysfs_type:file w_file_perms;
+r_dir_file(ueventd, sysfs_type)
+allow ueventd sysfs_type:{ file lnk_file } { relabelfrom relabelto setattr };
+allow ueventd sysfs_type:dir { relabelfrom relabelto setattr };
+allow ueventd tmpfs:chr_file rw_file_perms;
+allow ueventd dev_type:dir create_dir_perms;
+allow ueventd dev_type:lnk_file { create unlink };
+allow ueventd dev_type:chr_file { getattr create setattr unlink };
+allow ueventd dev_type:blk_file { getattr relabelfrom relabelto create setattr unlink };
+allow ueventd self:netlink_kobject_uevent_socket create_socket_perms_no_ioctl;
+allow ueventd efs_file:dir search;
+allow ueventd efs_file:file r_file_perms;
+
+# Get SELinux enforcing status.
+r_dir_file(ueventd, selinuxfs)
+
+# Access for /vendor/ueventd.rc and /vendor/firmware
+r_dir_file(ueventd, { vendor_file_type -vendor_app_file -vendor_overlay_file })
+
+# Access for /apex/*/firmware
+allow ueventd apex_mnt_dir:dir r_dir_perms;
+
+# Get file contexts for new device nodes
+allow ueventd file_contexts_file:file r_file_perms;
+
+# Use setfscreatecon() to label /dev directories and files.
+allow ueventd self:process setfscreate;
+
+# Allow ueventd to read androidboot.android_dt_dir from kernel cmdline or bootconfig.
+allow ueventd proc_cmdline:file r_file_perms;
+allow ueventd proc_bootconfig:file r_file_perms;
+
+# Everything is labeled as rootfs in recovery mode. ueventd has to execute
+# the dynamic linker and shared libraries.
+recovery_only(`
+ allow ueventd rootfs:file { r_file_perms execute };
+')
+
+# Suppress denials for ueventd to getattr /postinstall. This occurs when the
+# linker tries to resolve paths in ld.config.txt.
+dontaudit ueventd postinstall_mnt_dir:dir getattr;
+
+# ueventd loads modules in response to modalias events.
+allow ueventd self:global_capability_class_set sys_module;
+allow ueventd vendor_file:system module_load;
+allow ueventd kernel:key search;
+
+# ueventd is using bootstrap bionic
+allow ueventd system_bootstrap_lib_file:dir r_dir_perms;
+allow ueventd system_bootstrap_lib_file:file { execute read open getattr map };
+
+# Allow ueventd to run shell scripts from vendor
+allow ueventd vendor_shell_exec:file execute;
+
+#####
+##### neverallow rules
+#####
+
+# Restrict ueventd access on block devices to maintenence operations.
+neverallow ueventd dev_type:blk_file ~{ getattr relabelfrom relabelto create setattr unlink };
+
+# Only relabelto as we would never want to relabelfrom port_device
+neverallow ueventd port_device:chr_file ~{ getattr create setattr unlink relabelto };
+
+# Nobody should be able to ptrace ueventd
+neverallow * ueventd:process ptrace;
+
+# ueventd should never execute a program without changing to another domain.
+neverallow ueventd { file_type fs_type }:file execute_no_trans;