policy/modules/services/ssh.te

   1 policy_module(ssh, 2.2.0)
   2
   3 ########################################
   4 #
   5 # Declarations
   6 #
   7
   8 ## <desc>
   9 ##      <p>
  10 ##      allow host key based authentication
  11 ##      </p>
  12 ## </desc>
  13 gen_tunable(allow_ssh_keysign, false)
  14
  15 ## <desc>
  16 ##      <p>
  17 ##      Allow ssh logins as sysadm_r:sysadm_t
  18 ##      </p>
  19 ## </desc>
  20 gen_tunable(ssh_sysadm_login, false)
  21
  22 ## <desc>
  23 ##      <p>
  24 ##      allow sshd to forward port connections
  25 ##      </p>
  26 ## </desc>
  27 gen_tunable(sshd_forward_ports, false)
  28
  29 attribute ssh_server;
  30 attribute ssh_agent_type;
  31
  32 type ssh_keygen_t;
  33 type ssh_keygen_exec_t;
  34 init_system_domain(ssh_keygen_t, ssh_keygen_exec_t)
  35
  36 type sshd_exec_t;
  37 corecmd_executable_file(sshd_exec_t)
  38
  39 ssh_server_template(sshd)
  40 init_daemon_domain(sshd_t, sshd_exec_t)
  41
  42 type sshd_initrc_exec_t;
  43 init_script_file(sshd_initrc_exec_t)
  44
  45 type sshd_key_t;
  46 files_type(sshd_key_t)
  47
  48 type ssh_t;
  49 type ssh_exec_t;
  50 typealias ssh_t alias { user_ssh_t staff_ssh_t sysadm_ssh_t };
  51 typealias ssh_t alias { auditadm_ssh_t secadm_ssh_t };
  52 application_domain(ssh_t, ssh_exec_t)
  53 ubac_constrained(ssh_t)
  54
  55 type ssh_agent_exec_t;
  56 corecmd_executable_file(ssh_agent_exec_t)
  57
  58 type ssh_agent_tmp_t;
  59 typealias ssh_agent_tmp_t alias { user_ssh_agent_tmp_t staff_ssh_agent_tmp_t sysadm_ssh_agent_tmp_t };
  60 typealias ssh_agent_tmp_t alias { auditadm_ssh_agent_tmp_t secadm_ssh_agent_tmp_t };
  61 files_tmp_file(ssh_agent_tmp_t)
  62 ubac_constrained(ssh_agent_tmp_t)
  63
  64 type ssh_keysign_t;
  65 type ssh_keysign_exec_t;
  66 typealias ssh_keysign_t alias { user_ssh_keysign_t staff_ssh_keysign_t sysadm_ssh_keysign_t };
  67 typealias ssh_keysign_t alias { auditadm_ssh_keysign_t secadm_ssh_keysign_t };
  68 application_domain(ssh_keysign_t, ssh_keysign_exec_t)
  69 ubac_constrained(ssh_keysign_t)
  70
  71 type ssh_tmpfs_t;
  72 typealias ssh_tmpfs_t alias { user_ssh_tmpfs_t staff_ssh_tmpfs_t sysadm_ssh_tmpfs_t };
  73 typealias ssh_tmpfs_t alias { auditadm_ssh_tmpfs_t secadm_ssh_tmpfs_t };
  74 files_tmpfs_file(ssh_tmpfs_t)
  75 ubac_constrained(ssh_tmpfs_t)
  76
  77 type ssh_home_t;
  78 typealias ssh_home_t alias { home_ssh_t user_ssh_home_t user_home_ssh_t staff_home_ssh_t sysadm_home_ssh_t };
  79 typealias ssh_home_t alias { auditadm_home_ssh_t secadm_home_ssh_t };
  80 userdom_user_home_content(ssh_home_t)
  81 files_poly_parent(ssh_home_t)
  82
  83 ifdef(`enable_mcs',`
  84         init_ranged_daemon_domain(sshd_t, sshd_exec_t, s0 - mcs_systemhigh)
  85 ')
  86
  87 ##############################
  88 #
  89 # SSH client local policy
  90 #
  91
  92 allow ssh_t self:capability { setuid setgid dac_override dac_read_search };
  93 allow ssh_t self:process ~{ ptrace setcurrent setexec setfscreate setrlimit execmem execstack execheap };
  94 allow ssh_t self:fd use;
  95 allow ssh_t self:fifo_file rw_fifo_file_perms;
  96 allow ssh_t self:unix_dgram_socket { create_socket_perms sendto };
  97 allow ssh_t self:unix_stream_socket { create_stream_socket_perms connectto };
  98 allow ssh_t self:shm create_shm_perms;
  99 allow ssh_t self:sem create_sem_perms;
 100 allow ssh_t self:msgq create_msgq_perms;
 101 allow ssh_t self:msg { send receive };
 102 allow ssh_t self:tcp_socket create_stream_socket_perms;
 103 can_exec(ssh_t, ssh_exec_t)
 104
 105 # Read the ssh key file.
 106 allow ssh_t sshd_key_t:file read_file_perms;
 107
 108 manage_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 109 manage_lnk_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 110 manage_fifo_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 111 manage_sock_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 112 fs_tmpfs_filetrans(ssh_t, ssh_tmpfs_t, { dir file lnk_file sock_file fifo_file })
 113
 114 manage_dirs_pattern(ssh_t, ssh_home_t, ssh_home_t)
 115 manage_sock_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 116 userdom_user_home_dir_filetrans(ssh_t, ssh_home_t, { dir sock_file })
 117 userdom_stream_connect(ssh_t)
 118 userdom_search_admin_dir(sshd_t)
 119 userdom_admin_home_dir_filetrans(ssh_t, ssh_home_t, { dir sock_file })
 120
 121 # Allow the ssh program to communicate with ssh-agent.
 122 stream_connect_pattern(ssh_t, ssh_agent_tmp_t, ssh_agent_tmp_t, ssh_agent_type)
 123
 124 allow ssh_t sshd_t:unix_stream_socket connectto;
 125 allow ssh_t sshd_t:peer recv;
 126
 127 # ssh client can manage the keys and config
 128 manage_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 129 read_lnk_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 130
 131 # ssh servers can read the user keys and config
 132 manage_dirs_pattern(ssh_server, ssh_home_t, ssh_home_t)
 133 manage_files_pattern(ssh_server, ssh_home_t, ssh_home_t)
 134 userdom_user_home_dir_filetrans(ssh_server, ssh_home_t, dir)
 135 userdom_admin_home_dir_filetrans(ssh_server, ssh_home_t, dir)
 136
 137 kernel_read_kernel_sysctls(ssh_t)
 138 kernel_read_system_state(ssh_t)
 139
 140 corenet_all_recvfrom_unlabeled(ssh_t)
 141 corenet_all_recvfrom_netlabel(ssh_t)
 142 corenet_tcp_sendrecv_generic_if(ssh_t)
 143 corenet_tcp_sendrecv_generic_node(ssh_t)
 144 corenet_tcp_sendrecv_all_ports(ssh_t)
 145 corenet_tcp_connect_ssh_port(ssh_t)
 146 corenet_sendrecv_ssh_client_packets(ssh_t)
 147 corenet_tcp_bind_generic_node(ssh_t)
 148 corenet_tcp_bind_all_unreserved_ports(ssh_t)
 149
 150 dev_read_rand(ssh_t)
 151 dev_read_urand(ssh_t)
 152
 153 fs_getattr_all_fs(ssh_t)
 154 fs_search_auto_mountpoints(ssh_t)
 155
 156 # run helper programs - needed eg for x11-ssh-askpass
 157 corecmd_exec_shell(ssh_t)
 158 corecmd_exec_bin(ssh_t)
 159
 160 domain_use_interactive_fds(ssh_t)
 161
 162 files_list_home(ssh_t)
 163 files_read_usr_files(ssh_t)
 164 files_read_etc_runtime_files(ssh_t)
 165 files_read_etc_files(ssh_t)
 166 files_read_var_files(ssh_t)
 167
 168 logging_send_syslog_msg(ssh_t)
 169 logging_read_generic_logs(ssh_t)
 170
 171 auth_use_nsswitch(ssh_t)
 172
 173 miscfiles_read_localization(ssh_t)
 174 miscfiles_read_generic_certs(ssh_t)
 175
 176 seutil_read_config(ssh_t)
 177
 178 userdom_dontaudit_list_user_home_dirs(ssh_t)
 179 userdom_search_user_home_dirs(ssh_t)
 180 userdom_search_admin_dir(ssh_t)
 181 # Write to the user domain tty.
 182 userdom_use_inherited_user_terminals(ssh_t)
 183 # needs to read krb/write tgt
 184 userdom_read_user_tmp_files(ssh_t)
 185 userdom_write_user_tmp_files(ssh_t)
 186 userdom_read_user_home_content_symlinks(ssh_t)
 187 userdom_read_home_certs(ssh_t)
 188
 189 tunable_policy(`allow_ssh_keysign',`
 190         domtrans_pattern(ssh_t, ssh_keysign_exec_t, ssh_keysign_t)
 191 ')
 192
 193 tunable_policy(`use_fusefs_home_dirs',`
 194         fs_manage_fusefs_dirs(ssh_t)
 195         fs_manage_fusefs_files(ssh_t)
 196 ')
 197
 198 tunable_policy(`use_nfs_home_dirs',`
 199         fs_manage_nfs_dirs(ssh_t)
 200         fs_manage_nfs_files(ssh_t)
 201 ')
 202
 203 tunable_policy(`use_samba_home_dirs',`
 204         fs_manage_cifs_dirs(ssh_t)
 205         fs_manage_cifs_files(ssh_t)
 206 ')
 207
 208 # for port forwarding
 209 tunable_policy(`user_tcp_server',`
 210         corenet_tcp_bind_ssh_port(ssh_t)
 211         corenet_tcp_bind_generic_node(ssh_t)
 212 ')
 213
 214 optional_policy(`
 215         gnome_stream_connect_all_gkeyringd(ssh_t)
 216 ')
 217
 218 optional_policy(`
 219         xserver_user_x_domain_template(ssh, ssh_t, ssh_tmpfs_t)
 220         xserver_domtrans_xauth(ssh_t)
 221 ')
 222
 223
 224 ##############################
 225 #
 226 # ssh_keysign_t local policy
 227 #
 228
 229 tunable_policy(`allow_ssh_keysign',`
 230         allow ssh_keysign_t self:capability { setgid setuid };
 231         allow ssh_keysign_t self:unix_stream_socket create_socket_perms;
 232
 233         allow ssh_keysign_t sshd_key_t:file read_file_perms;
 234
 235         dev_read_rand(ssh_keysign_t)
 236         dev_read_urand(ssh_keysign_t)
 237
 238         files_read_etc_files(ssh_keysign_t)
 239 ')
 240
 241 optional_policy(`
 242         tunable_policy(`allow_ssh_keysign',`
 243                 nscd_socket_use(ssh_keysign_t)
 244         ')
 245 ')
 246
 247 #################################
 248 #
 249 # sshd local policy
 250 #
 251 # sshd_t is the domain for the sshd program.
 252 #
 253
 254 # so a tunnel can point to another ssh tunnel
 255 allow sshd_t self:netlink_route_socket r_netlink_socket_perms;
 256 allow sshd_t self:key { search link write };
 257 allow sshd_t self:process setcurrent;
 258
 259 kernel_search_key(sshd_t)
 260 kernel_link_key(sshd_t)
 261
 262 term_use_all_ptys(sshd_t)
 263 term_setattr_all_ptys(sshd_t)
 264 term_setattr_all_ttys(sshd_t)
 265 term_relabelto_all_ptys(sshd_t)
 266 term_use_ptmx(sshd_t)
 267
 268 # for X forwarding
 269 corenet_tcp_bind_xserver_port(sshd_t)
 270 corenet_sendrecv_xserver_server_packets(sshd_t)
 271
 272 userdom_read_user_home_content_files(sshd_t)
 273 userdom_read_user_home_content_symlinks(sshd_t)
 274 userdom_manage_tmp_role(system_r, sshd_t)
 275 userdom_spec_domtrans_unpriv_users(sshd_t)
 276 userdom_signal_unpriv_users(sshd_t)
 277
 278 tunable_policy(`sshd_forward_ports',`
 279         corenet_tcp_bind_all_unreserved_ports(sshd_t)
 280         corenet_tcp_connect_all_ports(sshd_t)
 281 ')
 282
 283 tunable_policy(`ssh_sysadm_login',`
 284         # Relabel and access ptys created by sshd
 285         # ioctl is necessary for logout() processing for utmp entry and for w to
 286         # display the tty.
 287         # some versions of sshd on the new SE Linux require setattr
 288         userdom_signal_all_users(sshd_t)
 289         userdom_spec_domtrans_all_users(sshd_t)
 290 ')
 291
 292 optional_policy(`
 293         amanda_search_var_lib(sshd_t)
 294 ')
 295
 296 optional_policy(`
 297         daemontools_service_domain(sshd_t, sshd_exec_t)
 298 ')
 299
 300 optional_policy(`
 301         kerberos_keytab_template(sshd, sshd_t)
 302 ')
 303
 304 optional_policy(`
 305         ftp_dyntrans_sftpd(sshd_t)
 306         ftp_dyntrans_anon_sftpd(sshd_t)
 307 ')
 308
 309 optional_policy(`
 310         gitosis_manage_lib_files(sshd_t)
 311 ')
 312
 313 optional_policy(`
 314         inetd_tcp_service_domain(sshd_t, sshd_exec_t)
 315 ')
 316
 317 optional_policy(`
 318         nx_read_home_files(sshd_t)
 319 ')
 320
 321 optional_policy(`
 322         rpm_use_script_fds(sshd_t)
 323 ')
 324
 325 optional_policy(`
 326         rssh_spec_domtrans(sshd_t)
 327         # For reading /home/user/.ssh
 328         rssh_read_ro_content(sshd_t)
 329 ')
 330
 331 optional_policy(`
 332         systemd_exec_systemctl(sshd_t)
 333 ')
 334
 335 optional_policy(`
 336         usermanage_domtrans_passwd(sshd_t)
 337         usermanage_read_crack_db(sshd_t)
 338 ')
 339
 340 optional_policy(`
 341         unconfined_shell_domtrans(sshd_t)
 342 ')
 343
 344 optional_policy(`
 345         xserver_domtrans_xauth(sshd_t)
 346 ')
 347
 348 ifdef(`TODO',`
 349         tunable_policy(`ssh_sysadm_login',`
 350                 # Relabel and access ptys created by sshd
 351                 # ioctl is necessary for logout() processing for utmp entry and for w to
 352                 # display the tty.
 353                 # some versions of sshd on the new SE Linux require setattr
 354                 allow sshd_t ptyfile:chr_file relabelto;
 355
 356                         optional_policy(`
 357                                 domain_trans(sshd_t, xauth_exec_t, userdomain)
 358                         ')
 359         ',`
 360                 optional_policy(`
 361                         domain_trans(sshd_t, xauth_exec_t, unpriv_userdomain)
 362                 ')
 363                 # Relabel and access ptys created by sshd
 364                 # ioctl is necessary for logout() processing for utmp entry and for w to
 365                 # display the tty.
 366                 # some versions of sshd on the new SE Linux require setattr
 367                 allow sshd_t userpty_type:chr_file { relabelto rw_inherited_chr_file_perms setattr_chr_file_perms };
 368         ')
 369 ') dnl endif TODO
 370
 371 ########################################
 372 #
 373 # ssh_keygen local policy
 374 #
 375
 376 # ssh_keygen_t is the type of the ssh-keygen program when run at install time
 377 # and by sysadm_t
 378
 379 allow ssh_keygen_t self:capability dac_override;
 380 dontaudit ssh_keygen_t self:capability sys_tty_config;
 381 allow ssh_keygen_t self:process { sigchld sigkill sigstop signull signal };
 382 allow ssh_keygen_t self:unix_stream_socket create_stream_socket_perms;
 383
 384 allow ssh_keygen_t sshd_key_t:file manage_file_perms;
 385 files_etc_filetrans(ssh_keygen_t, sshd_key_t, file)
 386
 387 manage_dirs_pattern(ssh_keygen_t, ssh_home_t, ssh_home_t)
 388 manage_files_pattern(ssh_keygen_t, ssh_home_t, ssh_home_t)
 389 userdom_admin_home_dir_filetrans(ssh_keygen_t, ssh_home_t, dir)
 390 userdom_user_home_dir_filetrans(ssh_keygen_t, ssh_home_t, dir)
 391
 392 kernel_read_kernel_sysctls(ssh_keygen_t)
 393
 394 fs_search_auto_mountpoints(ssh_keygen_t)
 395
 396 dev_read_sysfs(ssh_keygen_t)
 397 dev_read_rand(ssh_keygen_t)
 398 dev_read_urand(ssh_keygen_t)
 399
 400 term_dontaudit_use_console(ssh_keygen_t)
 401
 402 domain_use_interactive_fds(ssh_keygen_t)
 403
 404 files_read_etc_files(ssh_keygen_t)
 405
 406 init_use_fds(ssh_keygen_t)
 407 init_use_script_ptys(ssh_keygen_t)
 408
 409 auth_use_nsswitch(ssh_keygen_t)
 410
 411 logging_send_syslog_msg(ssh_keygen_t)
 412
 413 userdom_dontaudit_use_unpriv_user_fds(ssh_keygen_t)
 414 userdom_use_user_terminals(ssh_keygen_t)
 415
 416 optional_policy(`
 417     nscd_socket_use(ssh_keygen_t)
 418 ')
 419
 420 optional_policy(`
 421         seutil_sigchld_newrole(ssh_keygen_t)
 422 ')
 423
 424 optional_policy(`
 425         udev_read_db(ssh_keygen_t)
 426 ')