selinux-policy/refpolicy/policy/modules/services/ssh.te

policy_module(ssh,1.3.1)

########################################
#
# Declarations
#

attribute ssh_server;

# ssh client executable.
type ssh_exec_t;
corecmd_executable_file(ssh_exec_t)

type ssh_keygen_exec_t;
corecmd_executable_file(ssh_keygen_exec_t)

type ssh_keysign_exec_t;
files_type(ssh_keysign_exec_t)

# real declaration moved to mls until
# range_transition works in loadable modules
gen_require(`
	type sshd_exec_t;
')
corecmd_executable_file(sshd_exec_t)

type sshd_key_t;
files_type(sshd_key_t)

ifdef(`targeted_policy',`
	unconfined_alias_domain(sshd_t)
	init_system_domain(sshd_t,sshd_exec_t)

	type sshd_var_run_t;
	files_type(sshd_var_run_t)
',`
	# Type for the ssh-agent executable.
	type ssh_agent_exec_t;
	files_type(ssh_agent_exec_t)

	type ssh_keygen_t;
	init_system_domain(ssh_keygen_t,ssh_keygen_exec_t)
	role system_r types ssh_keygen_t;

	ssh_server_template(sshd)
	ssh_server_template(sshd_extern)

	# cjp: commenting this out until typeattribute works in a conditional
#	optional_policy(`
#		tunable_policy(`run_ssh_inetd',`
#			inetd_tcp_service_domain(sshd_t,sshd_exec_t)
#		',`
#			init_daemon_domain(sshd_t,sshd_exec_t)
#		')
#	',`
		# These rules should match the else block
		# of the run_ssh_inetd tunable directly above
		init_daemon_domain(sshd_t,sshd_exec_t)
#	')

	type sshd_tmp_t;
	files_tmp_file(sshd_tmp_t)
')

#################################
#
# sshd local policy
#
# sshd_t is the domain for the sshd program.
#

ifdef(`targeted_policy',`',`
	# so a tunnel can point to another ssh tunnel
	allow sshd_t self:tcp_socket { acceptfrom connectto recvfrom };

	allow sshd_t sshd_tmp_t:dir create_dir_perms;
	allow sshd_t sshd_tmp_t:file create_file_perms;
	allow sshd_t sshd_tmp_t:sock_file create_file_perms;
	files_tmp_filetrans(sshd_t, sshd_tmp_t, { dir file sock_file })

	# for X forwarding
	corenet_tcp_bind_xserver_port(sshd_t)

	mls_file_read_up(sshd_t)
	mls_file_write_down(sshd_t)
	mls_file_upgrade(sshd_t)
	mls_file_downgrade(sshd_t)
	mls_process_set_level(sshd_t)

	auth_exec_pam(sshd_t)

	seutil_read_config(sshd_t)

	tunable_policy(`ssh_sysadm_login',`
		# Relabel and access ptys created by sshd
		# ioctl is necessary for logout() processing for utmp entry and for w to
		# display the tty.
		# some versions of sshd on the new SE Linux require setattr
		term_use_all_user_ptys(sshd_t)
		term_setattr_all_user_ptys(sshd_t)
		term_relabelto_all_user_ptys(sshd_t)

		userdom_spec_domtrans_all_users(sshd_t)
		userdom_signal_all_users(sshd_t)
	',`
		userdom_spec_domtrans_unpriv_users(sshd_t)
		userdom_signal_unpriv_users(sshd_t)

		userdom_setattr_unpriv_users_ptys(sshd_t)
		userdom_relabelto_unpriv_users_ptys(sshd_t)
		userdom_use_unpriv_users_ptys(sshd_t)
	')

	optional_policy(`
		daemontools_service_domain(sshd_t, sshd_exec_t)
	')

	optional_policy(`
		rpm_use_script_fds(sshd_t)
	')

	ifdef(`TODO',`
	tunable_policy(`ssh_sysadm_login',`
		# Relabel and access ptys created by sshd
		# ioctl is necessary for logout() processing for utmp entry and for w to
		# display the tty.
		# some versions of sshd on the new SE Linux require setattr
		allow sshd_t ptyfile:chr_file relabelto;

		optional_policy(`
			domain_trans(sshd_t, xauth_exec_t, userdomain)
		')
	',`
		optional_policy(`
			domain_trans(sshd_t, xauth_exec_t, unpriv_userdomain)
		')
		# Relabel and access ptys created by sshd
		# ioctl is necessary for logout() processing for utmp entry and for w to
		# display the tty.
		# some versions of sshd on the new SE Linux require setattr
		allow sshd_t userpty_type:chr_file { relabelto read write getattr ioctl setattr };
	')
	') dnl endif TODO
')

#################################
#
# sshd_extern local policy
#
# sshd_extern_t is the domain for ssh from outside our network
#

ifdef(`targeted_policy',`',`
	ifdef(`TODO',`
	domain_trans(sshd_extern_t, shell_exec_t, user_mini_domain)
	# Signal the user domains.
	allow sshd_extern_t user_mini_domain:process signal;

	ifdef(`xauth.te', `
	domain_trans(sshd_extern_t, xauth_exec_t, user_mini_domain)
	')

	# Relabel and access ptys created by sshd
	# ioctl is necessary for logout() processing for utmp entry and for w to
	# display the tty.
	# some versions of sshd on the new SE Linux require setattr
	allow sshd_extern_t user_mini_domain:chr_file { relabelto read write getattr ioctl setattr };

	# inheriting stream sockets is needed for "ssh host command" as no pty
	# is allocated
	allow user_mini_domain sshd_extern_t:unix_stream_socket rw_stream_socket_perms;

	optional_policy(`
		tunable_policy(`run_ssh_inetd',`
			domain_trans(inetd_t, sshd_exec_t, sshd_extern_t)
		',`
			domain_trans(initrc_t, sshd_exec_t, sshd_extern_t)
		')
	',`
		# These rules should match the else block
		# of the run_ssh_inetd tunable directly above
		domain_trans(initrc_t, sshd_exec_t, sshd_extern_t)
	')

	ifdef(`direct_sysadm_daemon', `
	# Direct execution by sysadm_r.
	domain_auto_trans(sysadm_t, sshd_exec_t, sshd_t)
	role_transition sysadm_r sshd_exec_t system_r;
	')

	# for port forwarding
	allow userdomain sshd_t:tcp_socket { connectto recvfrom };
	allow sshd_t userdomain:tcp_socket { acceptfrom recvfrom };
	allow userdomain kernel_t:tcp_socket recvfrom;
	allow sshd_t kernel_t:tcp_socket recvfrom;
	') dnl endif TODO
')

########################################
#
# ssh_keygen local policy
#

ifdef(`targeted_policy',`',`
	# ssh_keygen_t is the type of the ssh-keygen program when run at install time
	# and by sysadm_t

	dontaudit ssh_keygen_t self:capability sys_tty_config;
	allow ssh_keygen_t self:process { sigchld sigkill sigstop signull signal };

	allow ssh_keygen_t self:unix_stream_socket create_stream_socket_perms;

	allow ssh_keygen_t sshd_key_t:file create_file_perms;
	files_etc_filetrans(ssh_keygen_t,sshd_key_t,file)

	kernel_read_kernel_sysctls(ssh_keygen_t)

	fs_search_auto_mountpoints(ssh_keygen_t)

	dev_read_sysfs(ssh_keygen_t)
	dev_read_urand(ssh_keygen_t)

	term_dontaudit_use_console(ssh_keygen_t)

	domain_use_interactive_fds(ssh_keygen_t)

	files_read_etc_files(ssh_keygen_t)

	init_use_fds(ssh_keygen_t)
	init_use_script_ptys(ssh_keygen_t)

	libs_use_ld_so(ssh_keygen_t)
	libs_use_shared_libs(ssh_keygen_t)

	logging_send_syslog_msg(ssh_keygen_t)

	allow ssh_keygen_t proc_t:dir r_dir_perms;
	allow ssh_keygen_t proc_t:lnk_file read;

	userdom_use_sysadm_ttys(ssh_keygen_t)
	userdom_dontaudit_use_unpriv_user_fds(ssh_keygen_t)

	# cjp: with the old daemon_(base_)domain being broken up into
	# a daemon and system interface, this probably is not needed:
	ifdef(`direct_sysadm_daemon',`
		userdom_dontaudit_use_sysadm_terms(ssh_keygen_t)
	')

	ifdef(`targeted_policy', `
		term_dontaudit_use_unallocated_ttys(ssh_keygen_t)
		term_dontaudit_use_generic_ptys(ssh_keygen_t)
		files_dontaudit_read_root_files(ssh_keygen_t)
	')

	optional_policy(`
		seutil_sigchld_newrole(ssh_keygen_t)
	')

	optional_policy(`
		udev_read_db(ssh_keygen_t)
	')
')