selinux-policy/refpolicy/policy/modules/services/ssh.if

566 lines
16 KiB
Plaintext

## <summary>Secure shell client and server policy.</summary>
#######################################
## <summary>
## The per user domain template for the ssh module.
## </summary>
## <desc>
## <p>
## This template creates a derived domains which are used
## for ssh client sessions and user ssh agents. A derived
## type is also created to protect the user ssh keys.
## </p>
## <p>
## This template is invoked automatically for each user, and
## generally does not need to be invoked directly
## by policy writers.
## </p>
## </desc>
## <param name="userdomain_prefix">
## The prefix of the user domain (e.g., user
## is the prefix for user_t).
## </param>
## <param name="user_domain">
## The type of the user domain.
## </param>
## <param name="user_role">
## The role associated with the user domain.
## </param>
#
template(`ssh_per_userdomain_template',`
gen_require(`
attribute ssh_server;
type ssh_exec_t, ssh_agent_exec_t;
type sshd_key_t, ssh_keysign_exec_t;
type sshd_tmp_t, sshd_t;
')
##############################
#
# Declarations
#
type $1_home_ssh_t;
userdom_home_file($1,$1_home_ssh_t)
role $3 types $1_ssh_t;
type $1_ssh_t;
domain_type($1_ssh_t)
domain_entry_file($1_ssh_t,ssh_exec_t)
type $1_ssh_agent_t;
domain_type($1_ssh_agent_t)
domain_entry_file($1_ssh_agent_t,ssh_agent_exec_t)
role $3 types $1_ssh_agent_t;
type $1_ssh_keysign_t; #, nscd_client_domain;
domain_type($1_ssh_keysign_t)
domain_entry_file($1_ssh_keysign_t,ssh_keysign_exec_t)
role $3 types $1_ssh_keysign_t;
##############################
#
# $1_ssh_t local policy
#
allow $1_ssh_t self:capability { setuid setgid dac_override dac_read_search };
allow $1_ssh_t self:process ~{ ptrace setcurrent setexec setfscreate setrlimit execmem execstack execheap };
allow $1_ssh_t self:fd use;
allow $1_ssh_t self:fifo_file { read getattr lock ioctl write append };
allow $1_ssh_t self:unix_dgram_socket { create ioctl read getattr write setattr append bind connect getopt setopt shutdown };
allow $1_ssh_t self:unix_stream_socket { create ioctl read getattr write setattr append bind connect getopt setopt shutdown listen accept };
allow $1_ssh_t self:unix_dgram_socket sendto;
allow $1_ssh_t self:unix_stream_socket connectto;
allow $1_ssh_t self:shm { associate getattr setattr create destroy read write lock unix_read unix_write };
allow $1_ssh_t self:sem { associate getattr setattr create destroy read write unix_read unix_write };
allow $1_ssh_t self:msgq { associate getattr setattr create destroy read write enqueue unix_read unix_write };
allow $1_ssh_t self:msg { send receive };
allow $1_ssh_t self:tcp_socket { create connect ioctl read getattr write setattr append bind getopt setopt shutdown };
# Transition from the user domain to the derived domain.
domain_auto_trans($2, ssh_exec_t, $1_ssh_t)
allow $2 $1_ssh_t:fd use;
allow $1_ssh_t $2:fd use;
allow $1_ssh_t $2:fifo_file rw_file_perms;
allow $1_ssh_t $2:process sigchld;
# Read the ssh key file.
allow $1_ssh_t sshd_key_t:file r_file_perms;
# Access the ssh temporary files.
allow $1_ssh_t sshd_tmp_t:dir create_dir_perms;
allow $1_ssh_t sshd_tmp_t:file create_file_perms;
files_filetrans_tmp($1_ssh_t, sshd_tmp_t, { file dir })
# for rsync
allow $1_ssh_t $2:unix_stream_socket rw_socket_perms;
allow $1_ssh_t $2:unix_stream_socket connectto;
# user can manage the keys and config
allow $2 $1_home_ssh_t:dir rw_dir_perms;
allow $2 $1_home_ssh_t:file create_file_perms;
allow $2 $1_home_ssh_t:lnk_file create_lnk_perms;
allow $2 $1_home_ssh_t:sock_file create_file_perms;
# 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 sshd_t:unix_stream_socket rw_stream_socket_perms;
# ssh client can manage the keys and config
allow $1_ssh_t $1_home_ssh_t:file create_file_perms;
allow $1_ssh_t $1_home_ssh_t:lnk_file { getattr read };
# ssh servers can read the user keys and config
allow ssh_server $1_home_ssh_t:dir r_dir_perms;
allow ssh_server $1_home_ssh_t:lnk_file r_file_perms;
allow ssh_server $1_home_ssh_t:file r_file_perms;
kernel_read_kernel_sysctl($1_ssh_t)
corenet_tcp_sendrecv_all_if($1_ssh_t)
corenet_raw_sendrecv_all_if($1_ssh_t)
corenet_tcp_sendrecv_all_nodes($1_ssh_t)
corenet_raw_sendrecv_all_nodes($1_ssh_t)
corenet_tcp_sendrecv_all_ports($1_ssh_t)
corenet_non_ipsec_sendrecv($1_ssh_t)
corenet_tcp_bind_all_nodes($1_ssh_t)
corenet_tcp_connect_ssh_port($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)
corecmd_list_sbin($1_ssh_t)
corecmd_read_sbin_symlink($1_ssh_t)
# cjp: these are probably not needed:
corecmd_read_sbin_file($1_ssh_t)
corecmd_read_sbin_pipe($1_ssh_t)
corecmd_read_sbin_socket($1_ssh_t)
domain_use_wide_inherit_fd($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)
libs_use_ld_so($1_ssh_t)
libs_use_shared_libs($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)
sysnet_read_config($1_ssh_t)
sysnet_dns_name_resolve($1_ssh_t)
userdom_use_unpriv_users_fd($1_ssh_t)
# Write to the user domain tty.
userdom_use_user_terminals($1,$1_ssh_t)
tunable_policy(`read_default_t',`
files_list_default($1_ssh_t)
files_read_default_files($1_ssh_t)
files_read_default_symlinks($1_ssh_t)
files_read_default_sockets($1_ssh_t)
files_read_default_pipes($1_ssh_t)
')
tunable_policy(`use_nfs_home_dirs',`
fs_manage_nfs_dirs($1_ssh_t)
fs_manage_nfs_files($1_ssh_t)
')
tunable_policy(`use_samba_home_dirs',`
fs_manage_cifs_dirs($1_ssh_t)
fs_manage_cifs_files($1_ssh_t)
')
# for port forwarding
tunable_policy(`user_tcp_server',`
corenet_tcp_bind_ssh_port($1_ssh_t)
')
optional_policy(`kerberos',`
kerberos_use($1_ssh_t)
')
optional_policy(`nis',`
nis_use_ypbind($1_ssh_t)
')
optional_policy(`nscd',`
nscd_use_socket($1_ssh_t)
')
ifdef(`TODO',`
# Read /var/run, /var/log.
allow $1_ssh_t var_run_t:dir r_dir_perms;
allow $1_ssh_t var_run_t:{ file lnk_file } r_file_perms;
allow $1_ssh_t $1_tmp_t:dir r_dir_perms;
# Access the users .ssh directory.
file_type_auto_trans({ sysadm_ssh_t $1_ssh_t }, $1_home_dir_t, $1_home_ssh_t, dir)
file_type_auto_trans($1_ssh_t, $1_home_dir_t, $1_home_ssh_t, sock_file)
allow sysadm_ssh_t $1_home_ssh_t:file create_file_perms;
allow sysadm_ssh_t $1_home_ssh_t:lnk_file { getattr read };
dontaudit $1_ssh_t $1_home_t:dir { getattr search };
# for /bin/sh used to execute xauth
dontaudit $1_ssh_t proc_t:{ lnk_file file } { getattr read };
# Inherit and use descriptors from gnome-pty-helper.
ifdef(`gnome-pty-helper.te', `allow $1_ssh_t $1_gph_t:fd use;')
# allow ps to show ssh
can_ps($1_t, $1_ssh_t)
# Connect to X server
x_client_domain($1_ssh, $1)
#allow ssh to access keys stored on removable media
# Should we have a boolean around this?
files_search_mnt($1_ssh_t)
r_dir_file($1_ssh_t, removable_t)
if (allow_ssh_keysign) {
domain_auto_trans($1_ssh_t, ssh_keysign_exec_t, $1_ssh_keysign_t)
allow $1_ssh_keysign_t sshd_key_t:file { getattr read };
allow $1_ssh_keysign_t self:capability { setgid setuid };
allow $1_ssh_keysign_t urandom_device_t:chr_file r_file_perms;
uses_shlib($1_ssh_keysign_t)
dontaudit $1_ssh_keysign_t selinux_config_t:dir search;
dontaudit $1_ssh_keysign_t proc_t:dir search;
dontaudit $1_ssh_keysign_t proc_t:{ lnk_file file } { getattr read };
allow $1_ssh_keysign_t usr_t:dir search;
allow $1_ssh_keysign_t etc_t:file { getattr read };
allow $1_ssh_keysign_t self:dir search;
allow $1_ssh_keysign_t self:file { getattr read };
allow $1_ssh_keysign_t self:unix_stream_socket create_socket_perms;
}
') dnl endif TODO
##############################
#
# $1_ssh_agent_t local policy
#
allow $1_ssh_agent_t self:process setrlimit;
allow $1_ssh_agent_t self:capability setgid;
allow $1_ssh_agent_t { $1_ssh_agent_t $2 }:process signull;
allow $1_ssh_t $1_ssh_agent_t:unix_stream_socket connectto;
# for ssh-add
allow $2 $1_ssh_agent_t:unix_stream_socket connectto;
# Allow the user shell to signal the ssh program.
allow $2 $1_ssh_agent_t:process signal;
# for the transition back to normal privs upon exec
allow $1_ssh_agent_t $2:fd use;
allow $2 $1_ssh_agent_t:fd use;
allow $2 $1_ssh_agent_t:fifo_file rw_file_perms;
allow $2 $1_ssh_agent_t:process sigchld;
# Allow the ssh program to communicate with ssh-agent.
allow $1_ssh_t sshd_t:unix_stream_socket connectto;
domain_auto_trans($2, ssh_agent_exec_t, $1_ssh_agent_t)
allow $2 $1_ssh_agent_t:fd use;
allow $1_ssh_agent_t $2:fd use;
allow $1_ssh_agent_t $2:fifo_file rw_file_perms;
allow $1_ssh_agent_t $2:process sigchld;
kernel_read_kernel_sysctl($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,$1_t)
corecmd_bin_domtrans($1_ssh_agent_t, $1_t)
domain_use_wide_inherit_fd($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($1_ssh_agent_t)
libs_use_ld_so($1_ssh_agent_t)
libs_use_shared_libs($1_ssh_agent_t)
logging_send_syslog_msg($1_ssh_agent_t)
miscfiles_read_localization($1_ssh_agent_t)
seutil_dontaudit_read_config($1_ssh_agent_t)
# Write to the user domain tty.
userdom_use_user_terminals($1,$1_ssh_agent_t)
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, $1_t)
')
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, $1_t)
')
optional_policy(`nis',`
nis_use_ypbind($1_ssh_agent_t)
')
# optional_policy(`xdm',`
# # KDM:
# xdm_sigchld($1_ssh_agent_t)
# ')
ifdef(`TODO',`
ifdef(`xdm.te',`
can_pipe_xdm($1_ssh_agent_t)
')
# allow ps to show ssh
can_ps($1_t, $1_ssh_agent_t)
dontaudit $1_ssh_agent_t proc_t:{ lnk_file file } { getattr read };
# Access the ssh temporary files. Should we have an own type here
# to which only ssh, ssh-agent and ssh-add have access?
allow $1_ssh_agent_t $1_tmp_t:dir r_dir_perms;
file_type_auto_trans($1_ssh_agent_t, tmp_t, $1_tmp_t)
# transition back to normal privs upon exec
domain_auto_trans($1_ssh_agent_t, $1_home_t, $1_t)
allow $1_ssh_agent_t $1_home_dir_t:dir search;
allow $1_ssh_t $1_tmp_t:sock_file write;
#
# Allow command to ssh-agent > ~/.ssh_agent
#
allow $1_ssh_agent_t $1_home_t:file rw_file_perms;
allow $1_ssh_agent_t $1_tmp_t:file rw_file_perms;
# Allow the ssh program to communicate with ssh-agent.
allow $1_ssh_t $1_tmp_t:sock_file write;
allow $1_ssh_t $2:unix_stream_socket connectto;
') dnl endif TODO
##############################
#
# $1_ssh_keysign_t local policy
#
optional_policy(`nscd',`
nscd_use_socket($1_ssh_keysign_t)
')
')
#######################################
## <summary>
## The template to define a ssh server.
## </summary>
## <desc>
## <p>
## 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.
## </p>
## </desc>
## <param name="userdomain_prefix">
## The prefix of the server domain (e.g., sshd
## is the prefix for sshd_t).
## </param>
#
template(`ssh_server_template', `
type $1_t, ssh_server;
domain_type($1_t)
role system_r types $1_t;
type $1_devpts_t;
term_login_pty($1_devpts_t)
type $1_var_run_t;
files_pid_file($1_var_run_t)
allow $1_t self:capability { kill sys_chroot sys_resource chown dac_override fowner fsetid setgid setuid sys_tty_config };
allow $1_t self:fifo_file rw_file_perms;
allow $1_t self:process { signal setsched setrlimit setexec };
allow $1_t self:tcp_socket { listen accept create connect ioctl read getattr write setattr append bind getopt setopt shutdown };
allow $1_t self:udp_socket { connect create ioctl read getattr write setattr append bind getopt setopt shutdown };
allow $1_t $1_devpts_t:chr_file { rw_file_perms setattr getattr relabelfrom };
term_create_pty($1_t,$1_devpts_t)
allow $1_t $1_var_run_t:file create_file_perms;
files_filetrans_pid($1_t,$1_var_run_t,file)
can_exec($1_t, sshd_exec_t)
# Access key files
allow $1_t sshd_key_t:file { getattr read };
kernel_read_kernel_sysctl($1_t)
corenet_tcp_sendrecv_all_if($1_t)
corenet_udp_sendrecv_all_if($1_t)
corenet_raw_sendrecv_all_if($1_t)
corenet_tcp_sendrecv_all_nodes($1_t)
corenet_udp_sendrecv_all_nodes($1_t)
corenet_raw_sendrecv_all_nodes($1_t)
corenet_udp_sendrecv_all_ports($1_t)
corenet_tcp_sendrecv_all_ports($1_t)
corenet_non_ipsec_sendrecv($1_t)
corenet_tcp_bind_all_nodes($1_t)
corenet_udp_bind_all_nodes($1_t)
corenet_tcp_connect_all_ports($1_t)
dev_read_urand($1_t)
fs_dontaudit_getattr_all_fs($1_t)
selinux_get_fs_mount($1_t)
selinux_validate_context($1_t)
selinux_compute_access_vector($1_t)
selinux_compute_create_context($1_t)
selinux_compute_relabel_context($1_t)
selinux_compute_user_contexts($1_t)
auth_dontaudit_read_shadow($1_t)
auth_domtrans_chk_passwd($1_t)
auth_rw_login_records($1_t)
auth_rw_lastlog($1_t)
auth_append_faillog($1_t)
corecmd_read_bin_symlink($1_t)
corecmd_getattr_bin_file($1_t)
# for sshd subsystems, such as sftp-server.
corecmd_getattr_bin_file($1_t)
domain_wide_inherit_fd($1_t)
domain_subj_id_change_exempt($1_t)
domain_role_change_exempt($1_t)
domain_obj_id_change_exempt($1_t)
files_read_etc_files($1_t)
files_read_etc_runtime_files($1_t)
init_rw_utmp($1_t)
libs_use_ld_so($1_t)
libs_use_shared_libs($1_t)
logging_search_logs($1_t)
logging_send_syslog_msg($1_t)
miscfiles_read_localization($1_t)
mls_file_read_up($1_t)
mls_file_write_down($1_t)
mls_file_upgrade($1_t)
mls_file_downgrade($1_t)
mls_process_set_level($1_t)
seutil_read_default_contexts($1_t)
sysnet_read_config($1_t)
userdom_search_all_users_home($1_t)
# Allow checking users mail at login
mta_getattr_spool($1_t)
tunable_policy(`use_nfs_home_dirs',`
fs_read_nfs_files($1_t)
')
tunable_policy(`use_samba_home_dirs',`
fs_read_cifs_files($1_t)
')
# cjp: commenting out until typeattribute works in conditional
# and require block in optional else is resolved
#optional_policy(`inetd',`
# tunable_policy(`run_ssh_inetd',`
# allow $1_t self:process signal;
# files_list_pids($1_t)
# ',`
# corenet_tcp_bind_ssh_port($1_t)
# init_use_fd($1_t)
# init_use_script_pty($1_t)
# ')
#',`
# These rules should match the else block
# of the run_ssh_inetd tunable directly above
corenet_tcp_bind_ssh_port($1_t)
init_use_fd($1_t)
init_use_script_pty($1_t)
#')
optional_policy(`kerberos',`
kerberos_use($1_t)
')
optional_policy(`mount',`
mount_send_nfs_client_request($1_t)
')
optional_policy(`nscd',`
nscd_use_socket($1_t)
')
ifdef(`TODO',`
# Read /var.
allow $1_t var_t:dir getattr;
allow $1_t home_dir_type:dir getattr;
dontaudit sshd_t userpty_type:chr_file relabelfrom;
') dnl end TODO
')
########################################
## <summary>Read ssh server keys</summary>
## <param name="domain">
## The type of the process performing this action.
## </param>
#
interface(`ssh_dontaudit_read_server_keys',`
gen_require(`
type sshd_key_t;
class file { getattr read };
')
dontaudit $1 sshd_key_t:file { getattr read };
')