selinux-policy/refpolicy/policy/modules/admin/su.if

328 lines
8.5 KiB
Plaintext

## <summary>Run shells with substitute user and group</summary>
template(`su_restricted_domain_template', `
gen_require(`
type su_exec_t;
')
type $1_su_t;
domain_entry_file($1_su_t,su_exec_t)
domain_type($1_su_t)
domain_role_change_exempt($1_su_t)
domain_subj_id_change_exempt($1_su_t)
domain_obj_id_change_exempt($1_su_t)
domain_wide_inherit_fd($1_su_t)
role $3 types $1_su_t;
allow $2 $1_su_t:process signal;
allow $1_su_t self:capability { audit_control audit_write setuid setgid net_bind_service chown dac_override fowner sys_nice sys_resource };
dontaudit $1_su_t self:capability sys_tty_config;
allow $1_su_t self:process { setexec setsched setrlimit };
allow $1_su_t self:fifo_file rw_file_perms;
allow $1_su_t self:netlink_audit_socket { nlmsg_relay create_netlink_socket_perms };
allow $1_su_t self:unix_stream_socket create_stream_socket_perms;
# Transition from the user domain to this domain.
domain_auto_trans($2, su_exec_t, $1_su_t)
allow $2 $1_su_t:fd use;
allow $1_su_t $2:fd use;
allow $1_su_t $2:fifo_file rw_file_perms;
allow $1_su_t $2:process sigchld;
# By default, revert to the calling domain when a shell is executed.
corecmd_shell_domtrans($1_su_t,$2)
allow $2 $1_su_t:fd use;
allow $1_su_t $2:fd use;
allow $1_su_t $2:fifo_file rw_file_perms;
allow $1_su_t $2:process sigchld;
kernel_read_system_state($1_su_t)
kernel_read_kernel_sysctl($1_su_t)
# for SSP
dev_read_urand($1_su_t)
selinux_get_fs_mount($1_su_t)
selinux_validate_context($1_su_t)
selinux_compute_access_vector($1_su_t)
selinux_compute_create_context($1_su_t)
selinux_compute_relabel_context($1_su_t)
selinux_compute_user_contexts($1_su_t)
auth_domtrans_chk_passwd($1_su_t)
auth_dontaudit_read_shadow($1_su_t)
auth_use_nsswitch($1_su_t)
domain_use_wide_inherit_fd($1_su_t)
files_read_etc_files($1_su_t)
files_search_var_lib($1_su_t)
init_dontaudit_use_fd($1_su_t)
init_dontaudit_use_script_pty($1_su_t)
# Write to utmp.
init_rw_script_pid($1_su_t)
libs_use_ld_so($1_su_t)
libs_use_shared_libs($1_su_t)
logging_send_syslog_msg($1_su_t)
miscfiles_read_localization($1_su_t)
seutil_read_config($1_su_t)
seutil_read_default_contexts($1_su_t)
# Only allow transitions to unprivileged user domains.
userdom_spec_domtrans_unpriv_users($1_su_t)
optional_policy(`cron',`
cron_read_pipe($1_su_t)
')
optional_policy(`kerberos',`
kerberos_use($1_su_t)
')
optional_policy(`nscd',`
nscd_use_socket($1_su_t)
')
ifdef(`TODO',`
# Caused by su - init scripts
dontaudit $1_su_t initrc_devpts_t:chr_file { getattr ioctl };
') dnl end TODO
')
#######################################
## <summary>
## The per user domain template for the su module.
## </summary>
## <desc>
## <p>
## This template creates a derived domain which is allowed
## to change the linux user id, to run shells as a different
## user.
## </p>
## <p>
## This template is invoked automatically for each user, and
## generally does not need to be invoked directly
## by policy writers.
## </p>
## </desc>
## <param name="userdomain_prefix">
## The prefix of the user domain (e.g., user
## is the prefix for user_t).
## </param>
## <param name="user_domain">
## The type of the user domain.
## </param>
## <param name="user_role">
## The role associated with the user domain.
## </param>
#
template(`su_per_userdomain_template',`
gen_require(`
type su_exec_t;
bool secure_mode;
')
type $1_su_t;
domain_entry_file($1_su_t,su_exec_t)
domain_type($1_su_t)
domain_role_change_exempt($1_su_t)
domain_subj_id_change_exempt($1_su_t)
domain_obj_id_change_exempt($1_su_t)
domain_wide_inherit_fd($1_su_t)
role $3 types $1_su_t;
allow $2 $1_su_t:process signal;
allow $1_su_t self:capability { audit_control audit_write setuid setgid net_bind_service chown dac_override fowner sys_nice sys_resource };
dontaudit $1_su_t self:capability sys_tty_config;
allow $1_su_t self:process { setexec setsched setrlimit };
allow $1_su_t self:fifo_file rw_file_perms;
allow $1_su_t self:netlink_audit_socket { nlmsg_relay create_netlink_socket_perms };
# Transition from the user domain to this domain.
domain_auto_trans($2, su_exec_t, $1_su_t)
allow $2 $1_su_t:fd use;
allow $1_su_t $2:fd use;
allow $1_su_t $2:fifo_file rw_file_perms;
allow $1_su_t $2:process sigchld;
# By default, revert to the calling domain when a shell is executed.
corecmd_shell_domtrans($1_su_t,$2)
allow $2 $1_su_t:fd use;
allow $1_su_t $2:fd use;
allow $1_su_t $2:fifo_file rw_file_perms;
allow $1_su_t $2:process sigchld;
kernel_read_system_state($1_su_t)
kernel_read_kernel_sysctl($1_su_t)
# for SSP
dev_read_urand($1_su_t)
fs_search_auto_mountpoints($1_su_t)
selinux_get_fs_mount($1_su_t)
selinux_validate_context($1_su_t)
selinux_compute_access_vector($1_su_t)
selinux_compute_create_context($1_su_t)
selinux_compute_relabel_context($1_su_t)
selinux_compute_user_contexts($1_su_t)
# Relabel ttys and ptys.
term_relabel_all_user_ttys($1_su_t)
term_relabel_all_user_ptys($1_su_t)
# Close and re-open ttys and ptys to get the fd into the correct domain.
term_use_all_user_ttys($1_su_t)
term_use_all_user_ptys($1_su_t)
auth_domtrans_user_chk_passwd($1,$1_su_t)
auth_dontaudit_read_shadow($1_su_t)
auth_use_nsswitch($1_su_t)
corecmd_search_bin($1_su_t)
corecmd_search_sbin($1_su_t)
domain_use_wide_inherit_fd($1_su_t)
files_read_etc_files($1_su_t)
files_search_var_lib($1_su_t)
init_dontaudit_use_fd($1_su_t)
# Write to utmp.
init_rw_script_pid($1_su_t)
libs_use_ld_so($1_su_t)
libs_use_shared_libs($1_su_t)
logging_send_syslog_msg($1_su_t)
miscfiles_read_localization($1_su_t)
seutil_read_config($1_su_t)
seutil_read_default_contexts($1_su_t)
userdom_use_user_terminals($1,$1_su_t)
userdom_search_user_home($1,$1_su_t)
ifdef(`targeted_policy',`
# allow user to suspend terminal.
# does not work in strict since the
# parent may not be able to use
# the terminal if we newrole,
# which relabels the terminal.
allow $1_su_t self:process sigstop;
corecmd_exec_bin($1_su_t)
userdom_manage_all_user_files($1_su_t)
userdom_manage_all_user_symlinks($1_su_t)
# newrole does not make any sense in
# the targeted policy. This is to
# make sediff easier.
if(!secure_mode) {
unconfined_domtrans($1_su_t)
unconfined_signal($1_su_t)
}
',`
if(secure_mode) {
# Only allow transitions to unprivileged user domains.
userdom_spec_domtrans_unpriv_users($1_su_t)
} else {
# Allow transitions to all user domains
userdom_spec_domtrans_all_users($1_su_t)
}
')
tunable_policy(`use_nfs_home_dirs',`
fs_search_nfs($1_su_t)
')
tunable_policy(`use_samba_home_dirs',`
fs_search_cifs($1_su_t)
')
optional_policy(`cron',`
cron_read_pipe($1_su_t)
')
optional_policy(`kerberos',`
kerberos_use($1_su_t)
')
optional_policy(`nscd',`
nscd_use_socket($1_su_t)
')
ifdef(`TODO',`
ifdef(`support_polyinstantiation', `
mls_file_read_up($1_su_t)
mls_file_write_down($1_su_t)
mls_file_upgrade($1_su_t)
mls_file_downgrade($1_su_t)
mls_process_set_level($1_su_t)
# Su can polyinstantiate
polyinstantiater($1_su_t)
# Su has to unmount polyinstantiated directories (like home)
# that should not be polyinstantiated under the new user
allow $1_su_t fs_t:filesystem unmount;
# Su needs additional permission to mount over a previous mount
allow $1_su_t polymember:dir mounton;
')
# Caused by su - init scripts
dontaudit $1_su_t initrc_devpts_t:chr_file { getattr ioctl };
# Inherit and use descriptors from gnome-pty-helper.
ifdef(`gnome-pty-helper.te', `allow $1_su_t $1_gph_t:fd use;')
allow $1_su_t $1_home_t:file create_file_perms;
ifdef(`user_canbe_sysadm', `
allow $1_su_t home_dir_type:dir { search write };
', `
dontaudit $1_su_t home_dir_type:dir { search write };
')
# Modify .Xauthority file (via xauth program).
ifdef(`xauth.te', `
file_type_auto_trans($1_su_t, staff_home_dir_t, staff_xauth_home_t, file)
file_type_auto_trans($1_su_t, user_home_dir_t, user_xauth_home_t, file)
file_type_auto_trans($1_su_t, sysadm_home_dir_t, sysadm_xauth_home_t, file)
domain_auto_trans($1_su_t, xauth_exec_t, $1_xauth_t)
')
ifdef(`cyrus.te', `
allow $1_su_t cyrus_var_lib_t:dir search;
')
ifdef(`ssh.te', `
# Access sshd cookie files.
allow $1_su_t sshd_tmp_t:file rw_file_perms;
file_type_auto_trans($1_su_t, sshd_tmp_t, $1_tmp_t)
')
') dnl end TODO
')
#######################################
## <summary>
## Execute su in the caller domain.
## </summary>
## <param name="domain">
## Domain allowed access.
## </param>
#
interface(`su_exec',`
gen_require(`
type su_exec_t;
')
can_exec($1,su_exec_t)
')