platform_system_sepolicy/public/runas.te

type runas, domain, mlstrustedsubject;
type runas_exec, system_file_type, exec_type, file_type;

allow runas adbd:fd use;
allow runas adbd:process sigchld;
allow runas adbd:unix_stream_socket { read write };
allow runas shell:fd use;
allow runas shell:fifo_file { read write };
allow runas shell:unix_stream_socket { read write };
allow runas devpts:chr_file { read write ioctl };
allow runas shell_data_file:file { read write };

# run-as reads package information.
allow runas system_data_file:file r_file_perms;
allow runas system_data_file:lnk_file getattr;

# The app's data dir may be accessed through a symlink.
allow runas system_data_file:lnk_file read;

# run-as checks and changes to the app data dir.
dontaudit runas self:global_capability_class_set { dac_override dac_read_search };
allow runas app_data_file:dir { getattr search };

# run-as switches to the app UID/GID.
allow runas self:global_capability_class_set { setuid setgid };

# run-as switches to the app security context.
selinux_check_context(runas) # validate context
allow runas self:process setcurrent;
allow runas non_system_app_set:process dyntransition; # setcon

# runas/libselinux needs access to seapp_contexts_file to
# determine which domain to transition to.
allow runas seapp_contexts_file:file r_file_perms;

###
### neverallow rules
###

# run-as cannot have capabilities other than CAP_SETUID and CAP_SETGID
neverallow runas self:global_capability_class_set ~{ setuid setgid };
neverallow runas self:global_capability2_class_set *;