platform_system_sepolicy/public/installd.te

# installer daemon
type installd, domain;
type installd_exec, exec_type, file_type;
typeattribute installd mlstrustedsubject;
allow installd self:global_capability_class_set { chown dac_override fowner fsetid setgid setuid sys_admin };

# Allow labeling of files under /data/app/com.example/oat/
allow installd dalvikcache_data_file:dir relabelto;
allow installd dalvikcache_data_file:file { relabelto link };

# Allow movement of APK files between volumes
allow installd apk_data_file:dir { create_dir_perms relabelfrom };
allow installd apk_data_file:file { create_file_perms relabelfrom link };
allow installd apk_data_file:lnk_file { create r_file_perms unlink };

allow installd asec_apk_file:file r_file_perms;
allow installd apk_tmp_file:file { r_file_perms unlink };
allow installd apk_tmp_file:dir { relabelfrom create_dir_perms };
allow installd oemfs:dir r_dir_perms;
allow installd oemfs:file r_file_perms;
allow installd cgroup:dir create_dir_perms;
allow installd mnt_expand_file:dir { search getattr };
# Check validity of SELinux context before use.
selinux_check_context(installd)

r_dir_file(installd, rootfs)
# Scan through APKs in /system/app and /system/priv-app
r_dir_file(installd, system_file)
# Scan through APKs in /vendor/app
r_dir_file(installd, vendor_app_file)
# Scan through Runtime Resource Overlay APKs in /vendor/overlay
r_dir_file(installd, vendor_overlay_file)
# Get file context
allow installd file_contexts_file:file r_file_perms;
# Get seapp_context
allow installd seapp_contexts_file:file r_file_perms;

# Search /data/app-asec and stat files in it.
allow installd asec_image_file:dir search;
allow installd asec_image_file:file getattr;

# Create /data/user and /data/user/0 if necessary.
# Also required to initially create /data/data subdirectories
# and lib symlinks before the setfilecon call.  May want to
# move symlink creation after setfilecon in installd.
allow installd system_data_file:dir create_dir_perms;
# Also, allow read for lnk_file so that we can process /data/user/0 links when
# optimizing application code.
allow installd system_data_file:lnk_file { create getattr read setattr unlink };

# Upgrade /data/media for multi-user if necessary.
allow installd media_rw_data_file:dir create_dir_perms;
allow installd media_rw_data_file:file { getattr unlink };
# restorecon new /data/media directory.
allow installd system_data_file:dir relabelfrom;
allow installd media_rw_data_file:dir relabelto;

# Delete /data/media files through sdcardfs, instead of going behind its back
allow installd tmpfs:dir r_dir_perms;
allow installd storage_file:dir search;
allow installd sdcardfs:dir { search open read write remove_name getattr rmdir };
allow installd sdcardfs:file { getattr unlink };

# Upgrade /data/misc/keychain for multi-user if necessary.
allow installd misc_user_data_file:dir create_dir_perms;
allow installd misc_user_data_file:file create_file_perms;
allow installd keychain_data_file:dir create_dir_perms;
allow installd keychain_data_file:file {r_file_perms unlink};

# Create /data/.layout_version.* file
allow installd install_data_file:file create_file_perms;

# Create files under /data/dalvik-cache.
allow installd dalvikcache_data_file:dir create_dir_perms;
allow installd dalvikcache_data_file:file create_file_perms;
allow installd dalvikcache_data_file:lnk_file getattr;

# Create files under /data/resource-cache.
allow installd resourcecache_data_file:dir rw_dir_perms;
allow installd resourcecache_data_file:file create_file_perms;

# Upgrade from unlabeled userdata.
# Just need enough to remove and/or relabel it.
allow installd unlabeled:dir { getattr search relabelfrom rw_dir_perms rmdir };
allow installd unlabeled:notdevfile_class_set { getattr relabelfrom rename unlink setattr };
# Read pkg.apk file for input during dexopt.
allow installd unlabeled:file r_file_perms;

# Upgrade from before system_app_data_file was used for system UID apps.
# Just need enough to relabel it and to unlink removed package files.
# Directory access covered by earlier rule above.
allow installd system_data_file:notdevfile_class_set { getattr relabelfrom unlink };

# Manage /data/data subdirectories, including initially labeling them
# upon creation via setfilecon or running restorecon_recursive,
# setting owner/mode, creating symlinks within them, and deleting them
# upon package uninstall.
# Types extracted from seapp_contexts type= fields.
allow installd {
    system_app_data_file
    bluetooth_data_file
    nfc_data_file
    radio_data_file
    shell_data_file
    app_data_file
    privapp_data_file
}:dir { create_dir_perms relabelfrom relabelto };

allow installd {
    system_app_data_file
    bluetooth_data_file
    nfc_data_file
    radio_data_file
    shell_data_file
    app_data_file
    privapp_data_file
}:notdevfile_class_set { create_file_perms relabelfrom relabelto };

# Similar for the files under /data/misc/profiles/
allow installd user_profile_data_file:dir create_dir_perms;
allow installd user_profile_data_file:file create_file_perms;
allow installd user_profile_data_file:dir rmdir;
allow installd user_profile_data_file:file unlink;

# Files created/updated by profman dumps.
allow installd profman_dump_data_file:dir { search add_name write };
allow installd profman_dump_data_file:file { create setattr open write };

# Create and use pty created by android_fork_execvp().
allow installd devpts:chr_file rw_file_perms;

# execute toybox for app relocation
allow installd toolbox_exec:file rx_file_perms;

# Allow installd to publish a binder service and make binder calls.
binder_use(installd)
add_service(installd, installd_service)
allow installd dumpstate:fifo_file  { getattr write };

# Allow installd to call into the system server so it can check permissions.
binder_call(installd, system_server)
allow installd permission_service:service_manager find;

# Allow installd to read and write quotas
allow installd block_device:dir { search };
allow installd labeledfs:filesystem { quotaget quotamod };

# Allow installd to delete from /data/preloads when trimming data caches
# TODO b/34690396 Remove when time-based purge policy for preloads is implemented in system_server
allow installd preloads_data_file:file { r_file_perms unlink };
allow installd preloads_data_file:dir { r_dir_perms write remove_name rmdir };
allow installd preloads_media_file:file { r_file_perms unlink };
allow installd preloads_media_file:dir { r_dir_perms write remove_name rmdir };

###
### Neverallow rules
###

# only system_server, installd and dumpstate may interact with installd over binder
neverallow { domain -system_server -dumpstate -installd } installd_service:service_manager find;
neverallow { domain -system_server -dumpstate } installd:binder call;
neverallow installd { domain -system_server -servicemanager userdebug_or_eng(`-su') }:binder call;