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 ## <desc>
  30 ## <p>
  31 ## Allow ssh with chroot env to read and write files
  32 ## in the user home directories
  33 ## </p>
  34 ## </desc>
  35 gen_tunable(ssh_chroot_rw_homedirs, false)
  36
  37 attribute ssh_dyntrasition_domain;
  38 attribute ssh_server;
  39 attribute ssh_agent_type;
  40
  41 ssh_dyntransition_domain_template(chroot_user_t)
  42 ssh_dyntransition_domain_template(sshd_sandbox_t)
  43
  44 type chroot_user_t;
  45 domain_type(chroot_user_t)
  46 role system_r types chroot_user_t;
  47
  48 type ssh_keygen_t;
  49 type ssh_keygen_exec_t;
  50 init_system_domain(ssh_keygen_t, ssh_keygen_exec_t)
  51
  52 type sshd_exec_t;
  53 corecmd_executable_file(sshd_exec_t)
  54
  55 ssh_server_template(sshd)
  56 init_daemon_domain(sshd_t, sshd_exec_t)
  57
  58 type sshd_initrc_exec_t;
  59 init_script_file(sshd_initrc_exec_t)
  60
  61 type sshd_key_t;
  62 files_type(sshd_key_t)
  63
  64 type ssh_t;
  65 type ssh_exec_t;
  66 typealias ssh_t alias { user_ssh_t staff_ssh_t sysadm_ssh_t };
  67 typealias ssh_t alias { auditadm_ssh_t secadm_ssh_t };
  68 application_domain(ssh_t, ssh_exec_t)
  69 ubac_constrained(ssh_t)
  70
  71 type ssh_agent_exec_t;
  72 corecmd_executable_file(ssh_agent_exec_t)
  73
  74 type ssh_agent_tmp_t;
  75 typealias ssh_agent_tmp_t alias { user_ssh_agent_tmp_t staff_ssh_agent_tmp_t sysadm_ssh_agent_tmp_t };
  76 typealias ssh_agent_tmp_t alias { auditadm_ssh_agent_tmp_t secadm_ssh_agent_tmp_t };
  77 files_tmp_file(ssh_agent_tmp_t)
  78 ubac_constrained(ssh_agent_tmp_t)
  79
  80 type ssh_keysign_t;
  81 type ssh_keysign_exec_t;
  82 typealias ssh_keysign_t alias { user_ssh_keysign_t staff_ssh_keysign_t sysadm_ssh_keysign_t };
  83 typealias ssh_keysign_t alias { auditadm_ssh_keysign_t secadm_ssh_keysign_t };
  84 application_domain(ssh_keysign_t, ssh_keysign_exec_t)
  85 ubac_constrained(ssh_keysign_t)
  86
  87 type ssh_tmpfs_t;
  88 typealias ssh_tmpfs_t alias { user_ssh_tmpfs_t staff_ssh_tmpfs_t sysadm_ssh_tmpfs_t };
  89 typealias ssh_tmpfs_t alias { auditadm_ssh_tmpfs_t secadm_ssh_tmpfs_t };
  90 files_tmpfs_file(ssh_tmpfs_t)
  91 ubac_constrained(ssh_tmpfs_t)
  92
  93 type ssh_home_t;
  94 typealias ssh_home_t alias { home_ssh_t user_ssh_home_t user_home_ssh_t staff_home_ssh_t sysadm_home_ssh_t };
  95 typealias ssh_home_t alias { auditadm_home_ssh_t secadm_home_ssh_t };
  96 userdom_user_home_content(ssh_home_t)
  97 files_poly_parent(ssh_home_t)
  98
  99 ifdef(`enable_mcs',`
 100         init_ranged_daemon_domain(sshd_t, sshd_exec_t, s0 - mcs_systemhigh)
 101 ')
 102
 103 ##############################
 104 #
 105 # SSH client local policy
 106 #
 107
 108 allow ssh_t self:capability { setuid setgid dac_override dac_read_search };
 109 allow ssh_t self:process ~{ ptrace setcurrent setexec setfscreate setrlimit execmem execstack execheap };
 110 allow ssh_t self:fd use;
 111 allow ssh_t self:fifo_file rw_fifo_file_perms;
 112 allow ssh_t self:unix_dgram_socket { create_socket_perms sendto };
 113 allow ssh_t self:unix_stream_socket { create_stream_socket_perms connectto };
 114 allow ssh_t self:shm create_shm_perms;
 115 allow ssh_t self:sem create_sem_perms;
 116 allow ssh_t self:msgq create_msgq_perms;
 117 allow ssh_t self:msg { send receive };
 118 allow ssh_t self:tcp_socket create_stream_socket_perms;
 119 can_exec(ssh_t, ssh_exec_t)
 120
 121 # Read the ssh key file.
 122 allow ssh_t sshd_key_t:file read_file_perms;
 123
 124 manage_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 125 manage_lnk_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 126 manage_fifo_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 127 manage_sock_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 128 fs_tmpfs_filetrans(ssh_t, ssh_tmpfs_t, { dir file lnk_file sock_file fifo_file })
 129
 130 manage_dirs_pattern(ssh_t, ssh_home_t, ssh_home_t)
 131 manage_sock_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 132 userdom_user_home_dir_filetrans(ssh_t, ssh_home_t, { dir sock_file })
 133 userdom_stream_connect(ssh_t)
 134 userdom_search_admin_dir(sshd_t)
 135 userdom_admin_home_dir_filetrans(ssh_t, ssh_home_t, { dir sock_file })
 136
 137 # Allow the ssh program to communicate with ssh-agent.
 138 stream_connect_pattern(ssh_t, ssh_agent_tmp_t, ssh_agent_tmp_t, ssh_agent_type)
 139
 140 allow ssh_t sshd_t:unix_stream_socket connectto;
 141 allow ssh_t sshd_t:peer recv;
 142
 143 # ssh client can manage the keys and config
 144 manage_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 145 read_lnk_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 146
 147 # ssh servers can read the user keys and config
 148 manage_dirs_pattern(ssh_server, ssh_home_t, ssh_home_t)
 149 manage_files_pattern(ssh_server, ssh_home_t, ssh_home_t)
 150 userdom_user_home_dir_filetrans(ssh_server, ssh_home_t, dir)
 151 userdom_admin_home_dir_filetrans(ssh_server, ssh_home_t, dir)
 152
 153 kernel_read_kernel_sysctls(ssh_t)
 154 kernel_read_system_state(ssh_t)
 155
 156 corenet_all_recvfrom_unlabeled(ssh_t)
 157 corenet_all_recvfrom_netlabel(ssh_t)
 158 corenet_tcp_sendrecv_generic_if(ssh_t)
 159 corenet_tcp_sendrecv_generic_node(ssh_t)
 160 corenet_tcp_sendrecv_all_ports(ssh_t)
 161 corenet_tcp_connect_ssh_port(ssh_t)
 162 corenet_sendrecv_ssh_client_packets(ssh_t)
 163 corenet_tcp_bind_generic_node(ssh_t)
 164 corenet_tcp_bind_all_unreserved_ports(ssh_t)
 165 corenet_rw_tun_tap_dev(ssh_t)
 166
 167 dev_read_rand(ssh_t)
 168 dev_read_urand(ssh_t)
 169
 170 fs_getattr_all_fs(ssh_t)
 171 fs_search_auto_mountpoints(ssh_t)
 172
 173 # run helper programs - needed eg for x11-ssh-askpass
 174 corecmd_exec_shell(ssh_t)
 175 corecmd_exec_bin(ssh_t)
 176
 177 domain_use_interactive_fds(ssh_t)
 178
 179 files_list_home(ssh_t)
 180 files_read_usr_files(ssh_t)
 181 files_read_etc_runtime_files(ssh_t)
 182 files_read_etc_files(ssh_t)
 183 files_read_var_files(ssh_t)
 184
 185 logging_send_syslog_msg(ssh_t)
 186 logging_read_generic_logs(ssh_t)
 187
 188 auth_use_nsswitch(ssh_t)
 189
 190 miscfiles_read_localization(ssh_t)
 191 miscfiles_read_generic_certs(ssh_t)
 192
 193 seutil_read_config(ssh_t)
 194
 195 userdom_dontaudit_list_user_home_dirs(ssh_t)
 196 userdom_search_user_home_dirs(ssh_t)
 197 userdom_search_admin_dir(ssh_t)
 198 # Write to the user domain tty.
 199 userdom_use_inherited_user_terminals(ssh_t)
 200 # needs to read krb/write tgt
 201 userdom_read_user_tmp_files(ssh_t)
 202 userdom_write_user_tmp_files(ssh_t)
 203 userdom_read_user_home_content_symlinks(ssh_t)
 204 userdom_read_home_certs(ssh_t)
 205
 206 tunable_policy(`allow_ssh_keysign',`
 207         domtrans_pattern(ssh_t, ssh_keysign_exec_t, ssh_keysign_t)
 208 ')
 209
 210 tunable_policy(`use_fusefs_home_dirs',`
 211         fs_manage_fusefs_dirs(ssh_t)
 212         fs_manage_fusefs_files(ssh_t)
 213 ')
 214
 215 tunable_policy(`use_nfs_home_dirs',`
 216         fs_manage_nfs_dirs(ssh_t)
 217         fs_manage_nfs_files(ssh_t)
 218 ')
 219
 220 tunable_policy(`use_samba_home_dirs',`
 221         fs_manage_cifs_dirs(ssh_t)
 222         fs_manage_cifs_files(ssh_t)
 223 ')
 224
 225 # for port forwarding
 226 tunable_policy(`user_tcp_server',`
 227         corenet_tcp_bind_ssh_port(ssh_t)
 228         corenet_tcp_bind_generic_node(ssh_t)
 229 ')
 230
 231 optional_policy(`
 232         gnome_stream_connect_all_gkeyringd(ssh_t)
 233 ')
 234
 235 optional_policy(`
 236         xserver_user_x_domain_template(ssh, ssh_t, ssh_tmpfs_t)
 237         xserver_domtrans_xauth(ssh_t)
 238 ')
 239
 240
 241 ##############################
 242 #
 243 # ssh_keysign_t local policy
 244 #
 245
 246 tunable_policy(`allow_ssh_keysign',`
 247         allow ssh_keysign_t self:capability { setgid setuid };
 248         allow ssh_keysign_t self:unix_stream_socket create_socket_perms;
 249
 250         allow ssh_keysign_t sshd_key_t:file read_file_perms;
 251
 252         dev_read_rand(ssh_keysign_t)
 253         dev_read_urand(ssh_keysign_t)
 254
 255         files_read_etc_files(ssh_keysign_t)
 256 ')
 257
 258 #################################
 259 #
 260 # sshd local policy
 261 #
 262 # sshd_t is the domain for the sshd program.
 263 #
 264
 265 # so a tunnel can point to another ssh tunnel
 266 allow sshd_t self:netlink_route_socket r_netlink_socket_perms;
 267 allow sshd_t self:key { search link write };
 268 allow sshd_t self:process setcurrent;
 269
 270 kernel_search_key(sshd_t)
 271 kernel_link_key(sshd_t)
 272
 273 term_use_all_ptys(sshd_t)
 274 term_setattr_all_ptys(sshd_t)
 275 term_setattr_all_ttys(sshd_t)
 276 term_relabelto_all_ptys(sshd_t)
 277 term_use_ptmx(sshd_t)
 278
 279 # for X forwarding
 280 corenet_tcp_bind_xserver_port(sshd_t)
 281 corenet_sendrecv_xserver_server_packets(sshd_t)
 282
 283 userdom_read_user_home_content_files(sshd_t)
 284 userdom_read_user_home_content_symlinks(sshd_t)
 285 userdom_manage_tmp_role(system_r, sshd_t)
 286 userdom_spec_domtrans_unpriv_users(sshd_t)
 287 userdom_signal_unpriv_users(sshd_t)
 288 userdom_dyntransition_unpriv_users(sshd_t)
 289
 290 tunable_policy(`sshd_forward_ports',`
 291         corenet_tcp_bind_all_unreserved_ports(sshd_t)
 292         corenet_tcp_connect_all_ports(sshd_t)
 293 ')
 294
 295 tunable_policy(`ssh_sysadm_login',`
 296         # Relabel and access ptys created by sshd
 297         # ioctl is necessary for logout() processing for utmp entry and for w to
 298         # display the tty.
 299         # some versions of sshd on the new SE Linux require setattr
 300         userdom_signal_all_users(sshd_t)
 301         userdom_spec_domtrans_all_users(sshd_t)
 302 ')
 303
 304 optional_policy(`
 305         amanda_search_var_lib(sshd_t)
 306 ')
 307
 308 optional_policy(`
 309         daemontools_service_domain(sshd_t, sshd_exec_t)
 310 ')
 311
 312 optional_policy(`
 313         kerberos_keytab_template(sshd, sshd_t)
 314 ')
 315
 316 optional_policy(`
 317         ftp_dyntrans_sftpd(sshd_t)
 318         ftp_dyntrans_anon_sftpd(sshd_t)
 319 ')
 320
 321 optional_policy(`
 322         gitosis_manage_lib_files(sshd_t)
 323 ')
 324
 325 optional_policy(`
 326         inetd_tcp_service_domain(sshd_t, sshd_exec_t)
 327 ')
 328
 329 optional_policy(`
 330         nx_read_home_files(sshd_t)
 331 ')
 332
 333 optional_policy(`
 334         rpm_use_script_fds(sshd_t)
 335 ')
 336
 337 optional_policy(`
 338         rssh_spec_domtrans(sshd_t)
 339         # For reading /home/user/.ssh
 340         rssh_read_ro_content(sshd_t)
 341 ')
 342
 343 optional_policy(`
 344         systemd_exec_systemctl(sshd_t)
 345 ')
 346
 347 optional_policy(`
 348         usermanage_domtrans_passwd(sshd_t)
 349         usermanage_read_crack_db(sshd_t)
 350 ')
 351
 352 optional_policy(`
 353         unconfined_shell_domtrans(sshd_t)
 354 ')
 355
 356 optional_policy(`
 357         xserver_domtrans_xauth(sshd_t)
 358 ')
 359
 360 ifdef(`TODO',`
 361         tunable_policy(`ssh_sysadm_login',`
 362                 # Relabel and access ptys created by sshd
 363                 # ioctl is necessary for logout() processing for utmp entry and for w to
 364                 # display the tty.
 365                 # some versions of sshd on the new SE Linux require setattr
 366                 allow sshd_t ptyfile:chr_file relabelto;
 367
 368                         optional_policy(`
 369                                 domain_trans(sshd_t, xauth_exec_t, userdomain)
 370                         ')
 371         ',`
 372                 optional_policy(`
 373                         domain_trans(sshd_t, xauth_exec_t, unpriv_userdomain)
 374                 ')
 375                 # Relabel and access ptys created by sshd
 376                 # ioctl is necessary for logout() processing for utmp entry and for w to
 377                 # display the tty.
 378                 # some versions of sshd on the new SE Linux require setattr
 379                 allow sshd_t userpty_type:chr_file { relabelto rw_inherited_chr_file_perms setattr_chr_file_perms };
 380         ')
 381 ') dnl endif TODO
 382
 383 ########################################
 384 #
 385 # ssh_keygen local policy
 386 #
 387
 388 # ssh_keygen_t is the type of the ssh-keygen program when run at install time
 389 # and by sysadm_t
 390
 391 allow ssh_keygen_t self:capability dac_override;
 392 dontaudit ssh_keygen_t self:capability sys_tty_config;
 393 allow ssh_keygen_t self:process { sigchld sigkill sigstop signull signal };
 394 allow ssh_keygen_t self:unix_stream_socket create_stream_socket_perms;
 395
 396 allow ssh_keygen_t sshd_key_t:file manage_file_perms;
 397 files_etc_filetrans(ssh_keygen_t, sshd_key_t, file)
 398
 399 manage_dirs_pattern(ssh_keygen_t, ssh_home_t, ssh_home_t)
 400 manage_files_pattern(ssh_keygen_t, ssh_home_t, ssh_home_t)
 401 userdom_admin_home_dir_filetrans(ssh_keygen_t, ssh_home_t, dir)
 402 userdom_user_home_dir_filetrans(ssh_keygen_t, ssh_home_t, dir)
 403
 404 kernel_read_system_state(ssh_keygen_t)
 405 kernel_read_kernel_sysctls(ssh_keygen_t)
 406
 407 fs_search_auto_mountpoints(ssh_keygen_t)
 408
 409 dev_read_sysfs(ssh_keygen_t)
 410 dev_read_rand(ssh_keygen_t)
 411 dev_read_urand(ssh_keygen_t)
 412
 413 term_dontaudit_use_console(ssh_keygen_t)
 414
 415 domain_use_interactive_fds(ssh_keygen_t)
 416
 417 files_read_etc_files(ssh_keygen_t)
 418
 419 init_use_fds(ssh_keygen_t)
 420 init_use_script_ptys(ssh_keygen_t)
 421
 422 auth_use_nsswitch(ssh_keygen_t)
 423
 424 logging_send_syslog_msg(ssh_keygen_t)
 425
 426 userdom_dontaudit_use_unpriv_user_fds(ssh_keygen_t)
 427 userdom_use_user_terminals(ssh_keygen_t)
 428
 429 optional_policy(`
 430         seutil_sigchld_newrole(ssh_keygen_t)
 431 ')
 432
 433 optional_policy(`
 434         udev_read_db(ssh_keygen_t)
 435 ')
 436
 437 ####################################
 438 #
 439 # ssh_dyntransition domain local policy
 440 #
 441
 442 allow ssh_dyntransition_domain self:capability { setuid sys_chroot setgid };
 443
 444 allow ssh_dyntransition_domain self:fifo_file rw_fifo_file_perms;
 445
 446 optional_policy(`
 447     ssh_rw_stream_sockets(ssh_dyntransition_domain)
 448     ssh_rw_tcp_sockets(ssh_dyntransition_domain)
 449 ')
 450
 451 #####################################
 452 #
 453 # ssh_sandbox local policy
 454 #
 455
 456 allow sshd_t sshd_sandbox_t:process signal;
 457
 458 init_ioctl_stream_sockets(sshd_sandbox_t)
 459
 460 logging_send_audit_msgs(sshd_sandbox_t)
 461
 462 ######################################
 463 #
 464 # chroot_user_t local policy
 465 #
 466
 467
 468 userdom_read_user_home_content_files(chroot_user_t)
 469 userdom_read_inherited_user_home_content_files(chroot_user_t)
 470 userdom_read_user_home_content_symlinks(chroot_user_t)
 471 userdom_exec_user_home_content_files(chroot_user_t)
 472
 473 tunable_policy(`ssh_chroot_rw_homedirs',`
 474         files_list_home(chroot_user_t)
 475         userdom_read_user_home_content_files(chroot_user_t)
 476         userdom_manage_user_home_content(chroot_user_t)
 477 ', `
 478
 479         userdom_user_home_dir_filetrans_pattern(chroot_user_t, { dir file lnk_file })
 480 ')
 481
 482 tunable_policy(`ssh_chroot_rw_homedirs && use_nfs_home_dirs',`
 483     fs_manage_nfs_dirs(chroot_user_t)
 484     fs_manage_nfs_files(chroot_user_t)
 485     fs_manage_nfs_symlinks(chroot_user_t)
 486 ')
 487
 488 tunable_policy(`ssh_chroot_rw_homedirs && use_samba_home_dirs',`
 489     fs_manage_cifs_dirs(chroot_user_t)
 490     fs_manage_cifs_files(chroot_user_t)
 491     fs_manage_cifs_symlinks(chroot_user_t)
 492 ')
 493
 494 tunable_policy(`use_samba_home_dirs',`
 495     fs_read_cifs_files(chroot_user_t)
 496     fs_read_cifs_symlinks(chroot_user_t)
 497 ')
 498
 499 tunable_policy(`use_nfs_home_dirs',`
 500     fs_read_nfs_files(chroot_user_t)
 501     fs_read_nfs_symlinks(chroot_user_t)
 502 ')
 503
 504 optional_policy(`
 505     ssh_rw_dgram_sockets(chroot_user_t)
 506 ')