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