On 1/20/21 2:50 PM, Dominick Grift wrote:
> Russell Coker <russell@xxxxxxxxxxxx> writes:
>
>> Second set of strict configuration patches. Ready for inclusion.
>>
>> Signed-off-by: Russell Coker <russell@xxxxxxxxxxxx>
>>
>> Index: refpolicy-2.20210120/policy/modules/system/userdomain.if
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/system/userdomain.if
>> +++ refpolicy-2.20210120/policy/modules/system/userdomain.if
>> @@ -68,6 +68,8 @@ template(`userdom_base_user_template',`
>> dontaudit $1_t user_tty_device_t:chr_file ioctl;
>>
>> kernel_read_kernel_sysctls($1_t)
>> + kernel_read_crypto_sysctls($1_t)
>> + kernel_read_vm_overcommit_sysctl($1_t)
>
> Probably more suitable for userdom_unpriv_user_template() instead
>
> This is the least required user template and so an effort should be made
> to keep this one really minimal.
>
>> kernel_dontaudit_list_unlabeled($1_t)
>> kernel_dontaudit_getattr_unlabeled_files($1_t)
>> kernel_dontaudit_getattr_unlabeled_symlinks($1_t)
>> @@ -3552,6 +3554,25 @@ interface(`userdom_delete_all_user_runti
>> ')
>>
>> ########################################
>> +## <summary>
>> +## write user runtime socket files
>> +## </summary>
>> +## <param name="domain">
>> +## <summary>
>> +## Domain allowed access.
>> +## </summary>
>> +## </param>
>> +#
>> +interface(`userdom_write_all_user_runtime_named_sockets',`
>> + gen_require(`
>> + attribute user_runtime_content_type;
>> + ')
>> +
>> + allow $1 user_runtime_content_type:dir list_dir_perms;
>> + allow $1 user_runtime_content_type:sock_file write;
>> +')
>
> I think this is just too broad. see below.
>
>> +
>> +########################################
>> ## <summary>
>> ## delete user runtime files
>> ## </summary>
>> Index: refpolicy-2.20210120/policy/modules/roles/sysadm.te
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/roles/sysadm.te
>> +++ refpolicy-2.20210120/policy/modules/roles/sysadm.te
>> @@ -33,11 +33,22 @@ ifndef(`enable_mls',`
>> # Local policy
>> #
>>
>> +allow sysadm_t self:netlink_generic_socket { create setopt bind write read };
>> +
>> +# for ptrace
>> +allow sysadm_t self:netlink_tcpdiag_socket { create write nlmsg_read
>> read };
>
> r_netlink_socket_perms (i suppose, but i dont know how this relates to
> ptrace ... might be the wrong place to add this)
>
>> +
>> +allow sysadm_t self:capability audit_write;
>
> Can you explain the above permission?
>
>> +allow sysadm_t self:system status;
>
> the status permission is *theorically* systemd specific (needs an ifdef init_systemd?)
>
> But regardless, and this is personal:
>
> Why associate all these permissions with the sysadm_t shell. Shells do
> not have systemd awareness. Why not just target whatever command is
> doing this instead so that we can enforce some integrity in the sysadm_t domain?
>
>> +
>> corecmd_exec_shell(sysadm_t)
>>
>> corenet_ib_access_unlabeled_pkeys(sysadm_t)
>> corenet_ib_manage_subnet_unlabeled_endports(sysadm_t)
>>
>> +domain_getsched_all_domains(sysadm_t)
>> +
>> +dev_read_cpuid(sysadm_t)
>> dev_read_kmsg(sysadm_t)
>>
>> mls_process_read_all_levels(sysadm_t)
>> @@ -55,6 +66,9 @@ init_admin(sysadm_t)
>> userdom_manage_user_home_dirs(sysadm_t)
>> userdom_home_filetrans_user_home_dir(sysadm_t)
>>
>> +# for systemd-analyze
>> +files_get_etc_unit_status(sysadm_t)
>
> See above
>
>> +
>> ifdef(`direct_sysadm_daemon',`
>> optional_policy(`
>> init_run_daemon(sysadm_t, sysadm_r)
>> @@ -1121,6 +1135,10 @@ optional_policy(`
>> ')
>>
>> optional_policy(`
>> + systemd_dbus_chat_logind(sysadm_t)
>> +')
>
> shells do not dbus chat with systemd-logind. associating rules with the
> sysadm_t shell instead of targeting commands will eventually lead to
> sysadm_t becoming a unconfined_t clone
>
>> +
>> +optional_policy(`
>> tboot_run_txtstat(sysadm_t, sysadm_r)
>> ')
>>
>> @@ -1188,6 +1206,7 @@ optional_policy(`
>> ')
>>
>> optional_policy(`
>> + dev_rw_generic_usb_dev(sysadm_t)
>
> shells do not write usb devices. If you want this kind of access then
> why not use unconfined_t shell?
>
>
>> usbmodules_run(sysadm_t, sysadm_r)
>> ')
>>
>> Index: refpolicy-2.20210120/policy/modules/services/xserver.if
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/services/xserver.if
>> +++ refpolicy-2.20210120/policy/modules/services/xserver.if
>> @@ -100,6 +100,7 @@ interface(`xserver_restricted_role',`
>> xserver_xsession_entry_type($2)
>> xserver_dontaudit_write_log($2)
>> xserver_stream_connect_xdm($2)
>> + xserver_use_user_fonts($2)
>> # certain apps want to read xdm.pid file
>> xserver_read_xdm_runtime_files($2)
>> # gnome-session creates socket under /tmp/.ICE-unix/
>> @@ -141,7 +142,7 @@ interface(`xserver_role',`
>> gen_require(`
>> type iceauth_home_t, xserver_t, xserver_tmp_t, xserver_tmpfs_t, xauth_home_t;
>> type user_fonts_t, user_fonts_cache_t, user_fonts_config_t;
>> - type mesa_shader_cache_t;
>> + type mesa_shader_cache_t, xdm_t;
>> ')
>>
>> xserver_restricted_role($1, $2)
>> @@ -184,6 +185,8 @@ interface(`xserver_role',`
>>
>> xserver_read_xkb_libs($2)
>>
>> + allow $2 xdm_t:unix_stream_socket accept;
>
> Looks weird, why would $2 have to accept connections on xdm_t unix
> stream sockets?
>
>> +
>> optional_policy(`
>> xdg_cache_filetrans($2, mesa_shader_cache_t, dir, "mesa_shader_cache")
>> ')
>> @@ -1239,6 +1242,7 @@ interface(`xserver_read_xkb_libs',`
>> allow $1 xkb_var_lib_t:dir list_dir_perms;
>> read_files_pattern($1, xkb_var_lib_t, xkb_var_lib_t)
>> read_lnk_files_pattern($1, xkb_var_lib_t, xkb_var_lib_t)
>> + allow $1 xkb_var_lib_t:file map;
>> ')
>>
>> ########################################
>> Index: refpolicy-2.20210120/policy/modules/services/dbus.if
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/services/dbus.if
>> +++ refpolicy-2.20210120/policy/modules/services/dbus.if
>> @@ -84,6 +84,7 @@ template(`dbus_role_template',`
>>
>> allow $3 $1_dbusd_t:unix_stream_socket connectto;
>> allow $3 $1_dbusd_t:dbus { send_msg acquire_svc };
>> + allow $1_dbusd_t $3:dbus send_msg;
>
> I do not believe this is needed, or that it should be part of this
> template (too broad)
>
>> allow $3 $1_dbusd_t:fd use;
>>
>> allow $3 system_dbusd_t:dbus { send_msg acquire_svc };
>> @@ -99,9 +100,13 @@ template(`dbus_role_template',`
>>
>> allow $1_dbusd_t $3:process sigkill;
>>
>> + allow $1_dbusd_t self:process getcap;
>> +
>> corecmd_bin_domtrans($1_dbusd_t, $3)
>> corecmd_shell_domtrans($1_dbusd_t, $3)
>>
>> + dev_read_sysfs($1_dbusd_t)
>> +
>> auth_use_nsswitch($1_dbusd_t)
>>
>> ifdef(`hide_broken_symptoms',`
>> @@ -111,6 +116,15 @@ template(`dbus_role_template',`
>> optional_policy(`
>> systemd_read_logind_runtime_files($1_dbusd_t)
>> ')
>> +
>> + optional_policy(`
>> + init_dbus_chat($1_dbusd_t)
>> + dbus_system_bus_client($1_dbusd_t)
>
> Why did you add this? is this to resolve dynamic users with systemd?
> Using dbus to resolve dynamic users was a fluke and has been
> reimplemented. So if this was added for that then its obsolete and it
> should be revisited with modern systemd
>
>> + ')
>> +
>> + optional_policy(`
>> + xdg_read_data_files($1_dbusd_t)
>> + ')
>
> Is this for ~/.local/share/dbus-1? I would probably consider creating a
> private xdg_data type for that , but thats subjective.
>
>> ')
>>
>> #######################################
>> Index: refpolicy-2.20210120/policy/modules/services/ssh.if
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/services/ssh.if
>> +++ refpolicy-2.20210120/policy/modules/services/ssh.if
>> @@ -439,6 +439,7 @@ template(`ssh_role_template',`
>> xserver_use_xdm_fds($1_ssh_agent_t)
>> xserver_rw_xdm_pipes($1_ssh_agent_t)
>> xserver_sigchld_xdm($1_ssh_agent_t)
>> + xserver_write_inherited_xsession_log($1_ssh_agent_t)
>
> this access should probably be allowed on application_domain level, but
> thats a personal opinion. Basicall stdout of all application domains is
> directed to the xsession log AFAIK.
>
> No strong feelings about this though as xserver is dead anyway.
>
>> ')
>> ')
>>
>> Index: refpolicy-2.20210120/policy/modules/kernel/corecommands.te
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/kernel/corecommands.te
>> +++ refpolicy-2.20210120/policy/modules/kernel/corecommands.te
>> @@ -13,7 +13,7 @@ attribute exec_type;
>> #
>> # bin_t is the type of files in the system bin/sbin directories.
>> #
>> -type bin_t alias { ls_exec_t sbin_t };
>> +type bin_t alias { ls_exec_t sbin_t systemd_analyze_exec_t };
>
> I wouldnt remove systemd_analyze_t but i will leave that for others to
> decide (obviously)
>
>> corecmd_executable_file(bin_t)
>> dev_associate(bin_t) #For /dev/MAKEDEV
>>
>> Index: refpolicy-2.20210120/policy/modules/system/systemd.te
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/system/systemd.te
>> +++ refpolicy-2.20210120/policy/modules/system/systemd.te
>> @@ -55,10 +55,6 @@ type systemd_activate_t;
>> type systemd_activate_exec_t;
>> init_system_domain(systemd_activate_t, systemd_activate_exec_t)
>>
>> -type systemd_analyze_t;
>> -type systemd_analyze_exec_t;
>> -init_daemon_domain(systemd_analyze_t, systemd_analyze_exec_t)
>> -
>> type systemd_backlight_t;
>> type systemd_backlight_exec_t;
>> init_system_domain(systemd_backlight_t, systemd_backlight_exec_t)
>> @@ -1361,6 +1357,7 @@ tunable_policy(`systemd_tmpfiles_manage_
>> ')
>>
>> optional_policy(`
>> + dbus_manage_lib_files(systemd_tmpfiles_t)
>> dbus_read_lib_files(systemd_tmpfiles_t)
>> dbus_relabel_lib_dirs(systemd_tmpfiles_t)
>> ')
>> Index: refpolicy-2.20210120/policy/modules/services/cron.te
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/services/cron.te
>> +++ refpolicy-2.20210120/policy/modules/services/cron.te
>> @@ -489,6 +489,7 @@ kernel_getattr_core_if(system_cronjob_t)
>> kernel_getattr_message_if(system_cronjob_t)
>>
>> kernel_read_crypto_sysctls(system_cronjob_t)
>> +kernel_read_fs_sysctls(system_cronjob_t)
>> kernel_read_irq_sysctls(system_cronjob_t)
>> kernel_read_kernel_sysctls(system_cronjob_t)
>> kernel_read_network_state(system_cronjob_t)
>> Index: refpolicy-2.20210120/policy/modules/apps/pulseaudio.te
>> ===================================================================
>> --- refpolicy-2.20210120.orig/policy/modules/apps/pulseaudio.te
>> +++ refpolicy-2.20210120/policy/modules/apps/pulseaudio.te
>> @@ -156,6 +156,7 @@ userdom_search_user_home_content(pulseau
>> userdom_manage_user_tmp_dirs(pulseaudio_t)
>> userdom_manage_user_tmp_files(pulseaudio_t)
>> userdom_manage_user_tmp_sockets(pulseaudio_t)
>> +userdom_write_all_user_runtime_named_sockets(pulseaudio_t)
forgot to comment on this one. this looks wrong. why did you add this?
dont want pulseaudio to write my gpg-agent sock file in
/run/user/UID/gnupg or anything except the pulseaudio socket for that matter
>>
>> tunable_policy(`pulseaudio_execmem',`
>> allow pulseaudio_t self:process execmem;
>>
>
