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_server;
  38 attribute ssh_agent_type;
  39
  40 type chroot_user_t;
  41 domain_type(chroot_user_t)
  42 role system_r types chroot_user_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:unix_dgram_socket { create_socket_perms sendto };
 109 allow ssh_t self:unix_stream_socket { create_stream_socket_perms connectto };
 110 allow ssh_t self:shm create_shm_perms;
 111 allow ssh_t self:sem create_sem_perms;
 112 allow ssh_t self:msgq create_msgq_perms;
 113 allow ssh_t self:msg { send receive };
 114 allow ssh_t self:tcp_socket create_stream_socket_perms;
 115 can_exec(ssh_t, ssh_exec_t)
 116
 117 # Read the ssh key file.
 118 allow ssh_t sshd_key_t:file read_file_perms;
 119
 120 manage_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 121 manage_lnk_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 122 manage_fifo_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 123 manage_sock_files_pattern(ssh_t, ssh_tmpfs_t, ssh_tmpfs_t)
 124 fs_tmpfs_filetrans(ssh_t, ssh_tmpfs_t, { dir file lnk_file sock_file fifo_file })
 125
 126 manage_dirs_pattern(ssh_t, ssh_home_t, ssh_home_t)
 127 manage_sock_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 128 userdom_user_home_dir_filetrans(ssh_t, ssh_home_t, { dir sock_file })
 129 userdom_stream_connect(ssh_t)
 130 userdom_search_admin_dir(sshd_t)
 131 userdom_admin_home_dir_filetrans(ssh_t, ssh_home_t, { dir sock_file })
 132
 133 # Allow the ssh program to communicate with ssh-agent.
 134 stream_connect_pattern(ssh_t, ssh_agent_tmp_t, ssh_agent_tmp_t, ssh_agent_type)
 135
 136 allow ssh_t sshd_t:unix_stream_socket connectto;
 137 allow ssh_t sshd_t:peer recv;
 138
 139 # ssh client can manage the keys and config
 140 manage_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 141 read_lnk_files_pattern(ssh_t, ssh_home_t, ssh_home_t)
 142
 143 # ssh servers can read the user keys and config
 144 manage_dirs_pattern(ssh_server, ssh_home_t, ssh_home_t)
 145 manage_files_pattern(ssh_server, ssh_home_t, ssh_home_t)
 146 userdom_user_home_dir_filetrans(ssh_server, ssh_home_t, dir)
 147 userdom_admin_home_dir_filetrans(ssh_server, ssh_home_t, dir)
 148
 149 kernel_read_kernel_sysctls(ssh_t)
 150 kernel_read_system_state(ssh_t)
 151
 152 corenet_all_recvfrom_unlabeled(ssh_t)
 153 corenet_all_recvfrom_netlabel(ssh_t)
 154 corenet_tcp_sendrecv_generic_if(ssh_t)
 155 corenet_tcp_sendrecv_generic_node(ssh_t)
 156 corenet_tcp_sendrecv_all_ports(ssh_t)
 157 corenet_tcp_connect_ssh_port(ssh_t)
 158 corenet_sendrecv_ssh_client_packets(ssh_t)
 159 corenet_tcp_bind_generic_node(ssh_t)
 160 corenet_tcp_bind_all_unreserved_ports(ssh_t)
 161 corenet_rw_tun_tap_dev(ssh_t)
 162
 163 dev_read_rand(ssh_t)
 164 dev_read_urand(ssh_t)
 165
 166 fs_getattr_all_fs(ssh_t)
 167 fs_search_auto_mountpoints(ssh_t)
 168
 169 # run helper programs - needed eg for x11-ssh-askpass
 170 corecmd_exec_shell(ssh_t)
 171 corecmd_exec_bin(ssh_t)
 172
 173 domain_use_interactive_fds(ssh_t)
 174
 175 files_list_home(ssh_t)
 176 files_read_usr_files(ssh_t)
 177 files_read_etc_runtime_files(ssh_t)
 178 files_read_etc_files(ssh_t)
 179 files_read_var_files(ssh_t)
 180
 181 logging_send_syslog_msg(ssh_t)
 182 logging_read_generic_logs(ssh_t)
 183
 184 auth_use_nsswitch(ssh_t)
 185
 186 miscfiles_read_localization(ssh_t)
 187 miscfiles_read_generic_certs(ssh_t)
 188
 189 seutil_read_config(ssh_t)
 190
 191 userdom_dontaudit_list_user_home_dirs(ssh_t)
 192 userdom_search_user_home_dirs(ssh_t)
 193 userdom_search_admin_dir(ssh_t)
 194 # Write to the user domain tty.
 195 userdom_use_inherited_user_terminals(ssh_t)
 196 # needs to read krb/write tgt
 197 userdom_read_user_tmp_files(ssh_t)
 198 userdom_write_user_tmp_files(ssh_t)
 199 userdom_read_user_home_content_symlinks(ssh_t)
 200 userdom_read_home_certs(ssh_t)
 201
 202 tunable_policy(`allow_ssh_keysign',`
 203         domtrans_pattern(ssh_t, ssh_keysign_exec_t, ssh_keysign_t)
 204 ')
 205
 206 tunable_policy(`use_fusefs_home_dirs',`
 207         fs_manage_fusefs_dirs(ssh_t)
 208         fs_manage_fusefs_files(ssh_t)
 209 ')
 210
 211 tunable_policy(`use_nfs_home_dirs',`
 212         fs_manage_nfs_dirs(ssh_t)
 213         fs_manage_nfs_files(ssh_t)
 214 ')
 215
 216 tunable_policy(`use_samba_home_dirs',`
 217         fs_manage_cifs_dirs(ssh_t)
 218         fs_manage_cifs_files(ssh_t)
 219 ')
 220
 221 # for port forwarding
 222 tunable_policy(`user_tcp_server',`
 223         corenet_tcp_bind_ssh_port(ssh_t)
 224         corenet_tcp_bind_generic_node(ssh_t)
 225 ')
 226
 227 optional_policy(`
 228         gnome_stream_connect_all_gkeyringd(ssh_t)
 229 ')
 230
 231 optional_policy(`
 232         xserver_user_x_domain_template(ssh, ssh_t, ssh_tmpfs_t)
 233         xserver_domtrans_xauth(ssh_t)
 234 ')
 235
 236
 237 ##############################
 238 #
 239 # ssh_keysign_t local policy
 240 #
 241
 242 tunable_policy(`allow_ssh_keysign',`
 243         allow ssh_keysign_t self:capability { setgid setuid };
 244         allow ssh_keysign_t self:unix_stream_socket create_socket_perms;
 245
 246         allow ssh_keysign_t sshd_key_t:file read_file_perms;
 247
 248         dev_read_rand(ssh_keysign_t)
 249         dev_read_urand(ssh_keysign_t)
 250
 251         files_read_etc_files(ssh_keysign_t)
 252 ')
 253
 254 #################################
 255 #
 256 # sshd local policy
 257 #
 258 # sshd_t is the domain for the sshd program.
 259 #
 260
 261 # so a tunnel can point to another ssh tunnel
 262 allow sshd_t self:netlink_route_socket r_netlink_socket_perms;
 263 allow sshd_t self:key { search link write };
 264 allow sshd_t self:process setcurrent;
 265
 266 kernel_search_key(sshd_t)
 267 kernel_link_key(sshd_t)
 268
 269 term_use_all_ptys(sshd_t)
 270 term_setattr_all_ptys(sshd_t)
 271 term_setattr_all_ttys(sshd_t)
 272 term_relabelto_all_ptys(sshd_t)
 273 term_use_ptmx(sshd_t)
 274
 275 # for X forwarding
 276 corenet_tcp_bind_xserver_port(sshd_t)
 277 corenet_sendrecv_xserver_server_packets(sshd_t)
 278
 279 userdom_read_user_home_content_files(sshd_t)
 280 userdom_read_user_home_content_symlinks(sshd_t)
 281 userdom_manage_tmp_role(system_r, sshd_t)
 282 userdom_spec_domtrans_unpriv_users(sshd_t)
 283 userdom_signal_unpriv_users(sshd_t)
 284 userdom_dyntransition_unpriv_users(sshd_t)
 285
 286 tunable_policy(`sshd_forward_ports',`
 287         corenet_tcp_bind_all_unreserved_ports(sshd_t)
 288         corenet_tcp_connect_all_ports(sshd_t)
 289 ')
 290
 291 tunable_policy(`ssh_sysadm_login',`
 292         # Relabel and access ptys created by sshd
 293         # ioctl is necessary for logout() processing for utmp entry and for w to
 294         # display the tty.
 295         # some versions of sshd on the new SE Linux require setattr
 296         userdom_signal_all_users(sshd_t)
 297         userdom_spec_domtrans_all_users(sshd_t)
 298 ')
 299
 300 optional_policy(`
 301         amanda_search_var_lib(sshd_t)
 302 ')
 303
 304 optional_policy(`
 305         daemontools_service_domain(sshd_t, sshd_exec_t)
 306 ')
 307
 308 optional_policy(`
 309         kerberos_keytab_template(sshd, sshd_t)
 310 ')
 311
 312 optional_policy(`
 313         ftp_dyntrans_sftpd(sshd_t)
 314         ftp_dyntrans_anon_sftpd(sshd_t)
 315 ')
 316
 317 optional_policy(`
 318         gitosis_manage_lib_files(sshd_t)
 319 ')
 320
 321 optional_policy(`
 322         inetd_tcp_service_domain(sshd_t, sshd_exec_t)
 323 ')
 324
 325 optional_policy(`
 326         nx_read_home_files(sshd_t)
 327 ')
 328
 329 optional_policy(`
 330         rpm_use_script_fds(sshd_t)
 331 ')
 332
 333 optional_policy(`
 334         rssh_spec_domtrans(sshd_t)
 335         # For reading /home/user/.ssh
 336         rssh_read_ro_content(sshd_t)
 337 ')
 338
 339 optional_policy(`
 340     ssh_dyntransition_chroot_user(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 # chroot_user_t local policy
 440 #
 441
 442 allow chroot_user_t self:capability { setuid sys_chroot setgid };
 443
 444 allow chroot_user_t self:fifo_file rw_fifo_file_perms;
 445
 446 userdom_read_user_home_content_files(chroot_user_t)
 447 userdom_read_inherited_user_home_content_files(chroot_user_t)
 448 userdom_read_user_home_content_symlinks(chroot_user_t)
 449 userdom_exec_user_home_content_files(chroot_user_t)
 450
 451 tunable_policy(`ssh_chroot_rw_homedirs',`
 452         files_list_home(chroot_user_t)
 453         userdom_read_user_home_content_files(chroot_user_t)
 454         userdom_manage_user_home_content(chroot_user_t)
 455 ', `
 456
 457         userdom_user_home_dir_filetrans_pattern(chroot_user_t, { dir file lnk_file })
 458 ')
 459
 460 tunable_policy(`ssh_chroot_rw_homedirs && use_nfs_home_dirs',`
 461     fs_manage_nfs_dirs(chroot_user_t)
 462     fs_manage_nfs_files(chroot_user_t)
 463     fs_manage_nfs_symlinks(chroot_user_t)
 464 ')
 465
 466 tunable_policy(`ssh_chroot_rw_homedirs && use_samba_home_dirs',`
 467     fs_manage_cifs_dirs(chroot_user_t)
 468     fs_manage_cifs_files(chroot_user_t)
 469     fs_manage_cifs_symlinks(chroot_user_t)
 470 ')
 471
 472 tunable_policy(`use_samba_home_dirs',`
 473     fs_read_cifs_files(chroot_user_t)
 474     fs_read_cifs_symlinks(chroot_user_t)
 475 ')
 476
 477 tunable_policy(`use_nfs_home_dirs',`
 478     fs_read_nfs_files(chroot_user_t)
 479     fs_read_nfs_symlinks(chroot_user_t)
 480 ')
 481
 482 optional_policy(`
 483     ssh_rw_stream_sockets(chroot_user_t)
 484     ssh_rw_tcp_sockets(chroot_user_t)
 485     ssh_rw_dgram_sockets(chroot_user_t)
 486 ')