## Secure shell client and server policy. ####################################### ## ## Basic SSH client template. ## ## ##

## This template creates a derived domains which are used ## for ssh client sessions. A derived ## type is also created to protect the user ssh keys. ##

##

## This template was added for NX. ##

##
## ## ## The prefix of the domain (e.g., user ## is the prefix for user_t). ## ## ## ## ## The type of the domain. ## ## ## ## ## The role associated with the user domain. ## ## # template(`ssh_basic_client_template',` gen_require(` attribute ssh_server; type ssh_exec_t, sshd_key_t, sshd_tmp_t; ') ############################## # # Declarations # type $1_ssh_t; application_domain($1_ssh_t, ssh_exec_t) role $3 types $1_ssh_t; type $1_ssh_home_t; files_type($1_ssh_home_t) ############################## # # Client local policy # allow $1_ssh_t self:capability { dac_override dac_read_search setgid setuid }; allow $1_ssh_t self:process { transition signal_perms getsched setsched getsession getpgid setpgid getcap setcap share getattr noatsecure siginh rlimitinh dyntransition setkeycreate setsockcreate getrlimit }; allow $1_ssh_t self:fd use; allow $1_ssh_t self:fifo_file rw_inherited_fifo_file_perms; allow $1_ssh_t self:unix_dgram_socket { create_socket_perms sendto }; allow $1_ssh_t self:unix_stream_socket { create_stream_socket_perms connectto }; allow $1_ssh_t self:shm create_shm_perms; allow $1_ssh_t self:sem create_sem_perms; allow $1_ssh_t self:msgq create_msgq_perms; allow $1_ssh_t self:msg { send receive }; allow $1_ssh_t self:tcp_socket create_stream_socket_perms; # for rsync allow $1_ssh_t $2:unix_stream_socket rw_socket_perms; allow $1_ssh_t $2:unix_stream_socket connectto; # Read the ssh key file. allow $1_ssh_t sshd_key_t:file read_file_perms; # Access the ssh temporary files. allow $1_ssh_t sshd_tmp_t:dir manage_dir_perms; allow $1_ssh_t sshd_tmp_t:file manage_file_perms; files_tmp_filetrans($1_ssh_t, sshd_tmp_t, { file dir }) # Transition from the domain to the derived domain. domtrans_pattern($2, ssh_exec_t, $1_ssh_t) # inheriting stream sockets is needed for "ssh host command" as no pty # is allocated # cjp: should probably fix target to be an attribute for ssh servers # or "regular" (not special like sshd_extern_t) servers allow $2 ssh_server:unix_stream_socket rw_stream_socket_perms; # allow ps to show ssh ps_process_pattern($2, $1_ssh_t) # user can manage the keys and config manage_files_pattern($2, $1_ssh_home_t, $1_ssh_home_t) manage_lnk_files_pattern($2, $1_ssh_home_t, $1_ssh_home_t) manage_sock_files_pattern($2, $1_ssh_home_t, $1_ssh_home_t) # ssh client can manage the keys and config manage_files_pattern($1_ssh_t, $1_ssh_home_t, $1_ssh_home_t) read_lnk_files_pattern($1_ssh_t, $1_ssh_home_t, $1_ssh_home_t) # ssh servers can read the user keys and config allow ssh_server $1_ssh_home_t:dir list_dir_perms; read_files_pattern(ssh_server, $1_ssh_home_t, $1_ssh_home_t) read_lnk_files_pattern(ssh_server, $1_ssh_home_t, $1_ssh_home_t) kernel_read_kernel_sysctls($1_ssh_t) kernel_read_system_state($1_ssh_t) corenet_all_recvfrom_netlabel($1_ssh_t) corenet_tcp_sendrecv_generic_if($1_ssh_t) corenet_tcp_sendrecv_generic_node($1_ssh_t) corenet_tcp_connect_ssh_port($1_ssh_t) corenet_sendrecv_ssh_client_packets($1_ssh_t) dev_read_urand($1_ssh_t) fs_getattr_all_fs($1_ssh_t) fs_search_auto_mountpoints($1_ssh_t) # run helper programs - needed eg for x11-ssh-askpass corecmd_exec_shell($1_ssh_t) corecmd_exec_bin($1_ssh_t) domain_use_interactive_fds($1_ssh_t) files_list_home($1_ssh_t) files_read_usr_files($1_ssh_t) files_read_etc_runtime_files($1_ssh_t) files_read_etc_files($1_ssh_t) files_read_var_files($1_ssh_t) auth_use_nsswitch($1_ssh_t) logging_send_syslog_msg($1_ssh_t) logging_read_generic_logs($1_ssh_t) miscfiles_read_localization($1_ssh_t) seutil_read_config($1_ssh_t) optional_policy(` kerberos_use($1_ssh_t) ') optional_policy(` systemd_user_app_status($1, $1_ssh_t) ') ') ####################################### ## ## The template to define a ssh server. ## ## ##

## This template creates a domains to be used for ## creating a ssh server. This is typically done ## to have multiple ssh servers of different sensitivities, ## such as for an internal network-facing ssh server, and ## a external network-facing ssh server. ##

##
## ## ## The prefix of the server domain (e.g., sshd ## is the prefix for sshd_t). ## ## # template(`ssh_server_template', ` gen_require(` attribute ssh_server; type sshd_exec_t, sshd_key_t; ') type $1_t, ssh_server; auth_login_pgm_domain($1_t) type $1_devpts_t; term_login_pty($1_devpts_t) type $1_runtime_t alias $1_var_run_t; files_runtime_file($1_runtime_t) type $1_tmpfs_t; files_tmpfs_file($1_tmpfs_t) allow $1_t self:capability { chown dac_read_search fowner fsetid kill setgid setuid sys_chroot sys_nice sys_resource sys_tty_config }; # net_admin is for SO_SNDBUFFORCE dontaudit $1_t self:capability net_admin; allow $1_t self:fifo_file rw_fifo_file_perms; allow $1_t self:process { signal getsched setsched setrlimit setexec setkeycreate }; allow $1_t self:tcp_socket create_stream_socket_perms; allow $1_t self:udp_socket create_socket_perms; # ssh agent connections: allow $1_t self:unix_stream_socket create_stream_socket_perms; allow $1_t self:shm create_shm_perms; allow $1_t $1_devpts_t:chr_file { rw_chr_file_perms setattr getattr relabelfrom }; term_create_pty($1_t, $1_devpts_t) manage_files_pattern($1_t, $1_tmpfs_t, $1_tmpfs_t) fs_tmpfs_filetrans($1_t, $1_tmpfs_t, file) allow $1_t $1_runtime_t:dir search_dir_perms; allow $1_t $1_runtime_t:file manage_file_perms; files_runtime_filetrans($1_t, $1_runtime_t, file) can_exec($1_t, sshd_exec_t) # Access key files allow $1_t sshd_key_t:file read_file_perms; kernel_read_kernel_sysctls($1_t) kernel_read_network_state($1_t) kernel_read_crypto_sysctls($1_t) corenet_all_recvfrom_netlabel($1_t) corenet_tcp_sendrecv_generic_if($1_t) corenet_udp_sendrecv_generic_if($1_t) corenet_raw_sendrecv_generic_if($1_t) corenet_tcp_sendrecv_generic_node($1_t) corenet_udp_sendrecv_generic_node($1_t) corenet_raw_sendrecv_generic_node($1_t) corenet_tcp_bind_generic_node($1_t) corenet_udp_bind_generic_node($1_t) corenet_tcp_bind_ssh_port($1_t) corenet_tcp_connect_all_ports($1_t) corenet_sendrecv_ssh_server_packets($1_t) fs_dontaudit_getattr_all_fs($1_t) auth_rw_login_records($1_t) auth_rw_faillog($1_t) # for sshd subsystems, such as sftp-server. corecmd_getattr_bin_files($1_t) domain_interactive_fd($1_t) files_read_etc_files($1_t) files_read_etc_runtime_files($1_t) files_read_usr_files($1_t) logging_search_logs($1_t) miscfiles_read_localization($1_t) userdom_create_all_users_keys($1_t) userdom_dontaudit_relabelfrom_user_ptys($1_t) userdom_search_user_home_dirs($1_t) # Allow checking users mail at login optional_policy(` mta_getattr_spool($1_t) ') tunable_policy(`use_nfs_home_dirs',` fs_read_nfs_files($1_t) fs_read_nfs_symlinks($1_t) ') tunable_policy(`use_samba_home_dirs',` fs_read_cifs_files($1_t) ') optional_policy(` kerberos_use($1_t) kerberos_manage_host_rcache($1_t) ') optional_policy(` files_read_var_lib_symlinks($1_t) nx_spec_domtrans_server($1_t) ') optional_policy(` systemd_read_logind_sessions_files($1_t) ') ') ######################################## ## ## Role access for ssh ## ## ## ## The prefix of the user role (e.g., user ## is the prefix for user_r). ## ## ## ## ## User domain for the role. ## ## ## ## ## User exec domain for execute and transition access. ## ## ## ## ## Role allowed access ## ## # template(`ssh_role_template',` gen_require(` attribute ssh_server, ssh_agent_type; type ssh_t, ssh_exec_t, ssh_home_t, ssh_agent_exec_t; type ssh_agent_tmp_t; ') ############################## # # Declarations # role $4 types ssh_t; type $1_ssh_agent_t, ssh_agent_type; userdom_user_application_domain($1_ssh_agent_t, ssh_agent_exec_t) domain_interactive_fd($1_ssh_agent_t) role $4 types $1_ssh_agent_t; ############################## # # Local policy # # Transition from the domain to the derived domain. domtrans_pattern($3, ssh_exec_t, ssh_t) # inheriting stream sockets is needed for "ssh host command" as no pty # is allocated allow $3 ssh_server:unix_stream_socket rw_stream_socket_perms; # allow ps to show ssh ps_process_pattern($3, ssh_t) allow $3 ssh_t:process signal; # for rsync allow ssh_t $3:unix_stream_socket rw_socket_perms; allow ssh_t $3:unix_stream_socket connectto; allow ssh_t $3:key manage_key_perms; # user can manage the keys and config manage_files_pattern($2, ssh_home_t, ssh_home_t) manage_lnk_files_pattern($2, ssh_home_t, ssh_home_t) manage_sock_files_pattern($2, ssh_home_t, ssh_home_t) userdom_search_user_home_dirs($1_t) optional_policy(` systemd_user_app_status($1, ssh_t) ') ############################## # # SSH agent local policy # allow $1_ssh_agent_t self:process { setrlimit signal }; allow $1_ssh_agent_t self:capability setgid; allow $1_ssh_agent_t self:fifo_file rw_fifo_file_perms; allow $1_ssh_agent_t { $1_ssh_agent_t $3 }:process signull; allow $1_ssh_agent_t self:unix_stream_socket { create_stream_socket_perms connectto }; manage_dirs_pattern($1_ssh_agent_t, ssh_agent_tmp_t, ssh_agent_tmp_t) manage_sock_files_pattern($1_ssh_agent_t, ssh_agent_tmp_t, ssh_agent_tmp_t) files_tmp_filetrans($1_ssh_agent_t, ssh_agent_tmp_t, { dir sock_file }) # for ssh-add stream_connect_pattern($3, ssh_agent_tmp_t, ssh_agent_tmp_t, $1_ssh_agent_t) # Allow the user shell to signal the ssh program. allow $3 $1_ssh_agent_t:process signal; # allow ps to show ssh ps_process_pattern($3, $1_ssh_agent_t) domtrans_pattern($3, ssh_agent_exec_t, $1_ssh_agent_t) kernel_read_kernel_sysctls($1_ssh_agent_t) dev_read_urand($1_ssh_agent_t) dev_read_rand($1_ssh_agent_t) fs_search_auto_mountpoints($1_ssh_agent_t) # transition back to normal privs upon exec corecmd_shell_domtrans($1_ssh_agent_t, $2) corecmd_bin_domtrans($1_ssh_agent_t, $2) domain_use_interactive_fds($1_ssh_agent_t) files_read_etc_files($1_ssh_agent_t) files_read_etc_runtime_files($1_ssh_agent_t) files_search_home($1_ssh_agent_t) libs_read_lib_files($1_ssh_agent_t) logging_send_syslog_msg($1_ssh_agent_t) miscfiles_read_localization($1_ssh_agent_t) miscfiles_read_generic_certs($1_ssh_agent_t) seutil_dontaudit_read_config($1_ssh_agent_t) # Write to the user domain tty. userdom_use_user_terminals($1_ssh_agent_t) # for the transition back to normal privs upon exec userdom_search_user_home_content($1_ssh_agent_t) userdom_user_home_domtrans($1_ssh_agent_t, $2) allow $3 $1_ssh_agent_t:fd use; allow $3 $1_ssh_agent_t:fifo_file rw_inherited_fifo_file_perms; allow $3 $1_ssh_agent_t:process sigchld; ifdef(`distro_debian', ` userdom_user_runtime_filetrans($1_ssh_agent_t, ssh_agent_tmp_t, sock_file) ') tunable_policy(`use_nfs_home_dirs',` fs_manage_nfs_files($1_ssh_agent_t) # transition back to normal privs upon exec fs_nfs_domtrans($1_ssh_agent_t, $2) ') tunable_policy(`use_samba_home_dirs',` fs_manage_cifs_files($1_ssh_agent_t) # transition back to normal privs upon exec fs_cifs_domtrans($1_ssh_agent_t, $2) ') optional_policy(` nis_use_ypbind($1_ssh_agent_t) ') optional_policy(` systemd_user_app_status($1, $1_ssh_agent_t) ') optional_policy(` tunable_policy(`ssh_use_gpg_agent',` # for ssh-add gpg_stream_connect_agent($3) ') ') optional_policy(` xserver_use_xdm_fds($1_ssh_agent_t) xserver_rw_xdm_pipes($1_ssh_agent_t) xserver_sigchld_xdm($1_ssh_agent_t) ') ') ######################################## ## ## Send a SIGCHLD signal to the ssh server. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_sigchld',` gen_require(` type sshd_t; ') allow $1 sshd_t:process sigchld; ') ######################################## ## ## Send a generic signal to the ssh server. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_signal',` gen_require(` type sshd_t; ') allow $1 sshd_t:process signal; ') ######################################## ## ## Send a null signal to sshd processes. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_signull',` gen_require(` type sshd_t; ') allow $1 sshd_t:process signull; ') ######################################## ## ## Read a ssh server unnamed pipe. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_read_pipes',` gen_require(` type sshd_t; ') allow $1 sshd_t:fifo_file { getattr read }; ') ######################################## ## ## Read and write a ssh server unnamed pipe. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_rw_pipes',` gen_require(` type sshd_t; ') allow $1 sshd_t:fifo_file rw_inherited_fifo_file_perms; ') ######################################## ## ## Read and write ssh server unix domain stream sockets. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_rw_stream_sockets',` gen_require(` type sshd_t; ') allow $1 sshd_t:unix_stream_socket rw_stream_socket_perms; ') ######################################## ## ## Read and write ssh server TCP sockets. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_rw_tcp_sockets',` gen_require(` type sshd_t; ') allow $1 sshd_t:tcp_socket rw_stream_socket_perms; ') ######################################## ## ## Do not audit attempts to read and write ## ssh server TCP sockets. ## ## ## ## Domain to not audit. ## ## # interface(`ssh_dontaudit_rw_tcp_sockets',` gen_require(` type sshd_t; ') dontaudit $1 sshd_t:tcp_socket { read write }; ') ######################################## ## ## Execute the ssh daemon in the caller domain. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_exec_sshd',` gen_require(` type sshd_exec_t; ') corecmd_search_bin($1) can_exec($1, sshd_exec_t) ') ######################################## ## ## Execute the ssh daemon sshd domain. ## ## ## ## Domain allowed to transition. ## ## # interface(`ssh_domtrans',` gen_require(` type sshd_t, sshd_exec_t; ') domtrans_pattern($1, sshd_exec_t, sshd_t) ') ######################################## ## ## Execute the ssh client in the ssh client domain. ## ## ## ## Domain allowed to transition. ## ## # interface(`ssh_client_domtrans',` gen_require(` type ssh_t, ssh_exec_t; ') domtrans_pattern($1, ssh_exec_t, ssh_t) ') ######################################## ## ## Execute the ssh client in the caller domain. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_exec',` gen_require(` type ssh_exec_t; ') corecmd_search_bin($1) can_exec($1, ssh_exec_t) ') ######################################## ## ## Set the attributes of sshd key files. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_setattr_key_files',` gen_require(` type sshd_key_t; ') allow $1 sshd_key_t:file setattr; files_search_runtime($1) ') ######################################## ## ## Execute the ssh agent client in the caller domain. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_agent_exec',` gen_require(` type ssh_agent_exec_t; ') corecmd_search_bin($1) can_exec($1, ssh_agent_exec_t) ') ######################################## ## ## Read ssh home directory content ## ## ## ## Domain allowed access. ## ## # interface(`ssh_read_user_home_files',` gen_require(` type ssh_home_t; ') allow $1 ssh_home_t:dir list_dir_perms; read_files_pattern($1, ssh_home_t, ssh_home_t) read_lnk_files_pattern($1, ssh_home_t, ssh_home_t) userdom_search_user_home_dirs($1) ') ######################################## ## ## Execute the ssh key generator in the ssh keygen domain. ## ## ## ## Domain allowed to transition. ## ## # interface(`ssh_domtrans_keygen',` gen_require(` type ssh_keygen_t, ssh_keygen_exec_t; ') domtrans_pattern($1, ssh_keygen_exec_t, ssh_keygen_t) ') ######################################## ## ## Read ssh server keys ## ## ## ## Domain to not audit. ## ## # interface(`ssh_dontaudit_read_server_keys',` gen_require(` type sshd_key_t; ') dontaudit $1 sshd_key_t:file { getattr read }; ') ###################################### ## ## Manage ssh home directory content ## ## ## ## Domain allowed access. ## ## # interface(`ssh_manage_home_files',` gen_require(` type ssh_home_t; ') manage_files_pattern($1, ssh_home_t, ssh_home_t) userdom_search_user_home_dirs($1) ') ####################################### ## ## Delete from the ssh temp files. ## ## ## ## Domain allowed access. ## ## # interface(`ssh_delete_tmp',` gen_require(` type sshd_tmp_t; ') files_search_tmp($1) delete_files_pattern($1, sshd_tmp_t, sshd_tmp_t) ') ####################################### ## ## dontaudit access to ssh agent tmp dirs ## ## ## ## Domain not to audit. ## ## # interface(`ssh_dontaudit_agent_tmp',` gen_require(` type ssh_agent_tmp_t; ') dontaudit $1 ssh_agent_tmp_t:dir list_dir_perms; ')