[PATCH v3 3/4] Makefile: add linker script to minimize exports

[bill.c.roberts@gmail.com]

From: William Roberts <william.c.roberts@intel.com>

Add a linker script that exports only what was previosly exported by
libselinux.

This was checked by generating an old export map (from master):
nm --defined-only -g ./src/libselinux.so | cut -d' ' -f 3-3 | grep -v '^_' > old.map

Then creating a new one for this library after this patch is applied:
nm --defined-only -g ./src/libselinux.so | cut -d' ' -f 3-3 | grep -v '^_' > new.map

And diffing them:
diff old.map new.map

Fixes: #179

Signed-off-by: William Roberts <william.c.roberts@intel.com>
---
 libselinux/src/Makefile       |   2 +-
 libselinux/src/libselinux.map | 249 ++++++++++++++++++++++++++++++++++
 2 files changed, 250 insertions(+), 1 deletion(-)
 create mode 100644 libselinux/src/libselinux.map

diff --git a/libselinux/src/Makefile b/libselinux/src/Makefile
index c76110fbc650..f74dbeb983dd 100644
--- a/libselinux/src/Makefile
+++ b/libselinux/src/Makefile
@@ -90,7 +90,7 @@ CFLAGS ?= -O -Wall -W -Wundef -Wformat-y2k -Wformat-security -Winit-self -Wmissi
           -Werror -Wno-aggregate-return -Wno-redundant-decls \
           $(EXTRA_CFLAGS)
 
-LD_SONAME_FLAGS=-soname,$(LIBSO),-z,defs,-z,relro
+LD_SONAME_FLAGS=-soname,$(LIBSO),-z,defs,-z,relro-Wl,--version-script=libselinux.map
 
 ifeq ($(OS), Darwin)
 override CFLAGS += -I/opt/local/include
diff --git a/libselinux/src/libselinux.map b/libselinux/src/libselinux.map
new file mode 100644
index 000000000000..73f4c072af02
--- /dev/null
+++ b/libselinux/src/libselinux.map
@@ -0,0 +1,249 @@
+LIBSELINUX_1.0 {
+  global:
+    avc_add_callback;
+    avc_audit;
+    avc_av_stats;
+    avc_cache_stats;
+    avc_cleanup;
+    avc_compute_create;
+    avc_compute_member;
+    avc_context_to_sid;
+    avc_context_to_sid_raw;
+    avc_destroy;
+    avc_get_initial_sid;
+    avc_has_perm;
+    avc_has_perm_noaudit;
+    avc_init;
+    avc_netlink_acquire_fd;
+    avc_netlink_check_nb;
+    avc_netlink_close;
+    avc_netlink_loop;
+    avc_netlink_open;
+    avc_netlink_release_fd;
+    avc_open;
+    avc_reset;
+    avc_sid_stats;
+    avc_sid_to_context;
+    avc_sid_to_context_raw;
+    checkPasswdAccess;
+    context_free;
+    context_new;
+    context_range_get;
+    context_range_set;
+    context_role_get;
+    context_role_set;
+    context_str;
+    context_type_get;
+    context_type_set;
+    context_user_get;
+    context_user_set;
+    dir_xattr_list;
+    fgetfilecon;
+    fgetfilecon_raw;
+    fini_selinuxmnt;
+    freecon;
+    freeconary;
+    fsetfilecon;
+    fsetfilecon_raw;
+    getcon;
+    getcon_raw;
+    get_default_context;
+    get_default_context_with_level;
+    get_default_context_with_role;
+    get_default_context_with_rolelevel;
+    get_default_type;
+    getexeccon;
+    getexeccon_raw;
+    getfilecon;
+    getfilecon_raw;
+    getfscreatecon;
+    getfscreatecon_raw;
+    getkeycreatecon;
+    getkeycreatecon_raw;
+    get_ordered_context_list;
+    get_ordered_context_list_with_level;
+    getpeercon;
+    getpeercon_raw;
+    getpidcon;
+    getpidcon_raw;
+    getprevcon;
+    getprevcon_raw;
+    getseuser;
+    getseuserbyname;
+    getsockcreatecon;
+    getsockcreatecon_raw;
+    is_context_customizable;
+    is_selinux_enabled;
+    is_selinux_mls_enabled;
+    lgetfilecon;
+    lgetfilecon_raw;
+    lsetfilecon;
+    lsetfilecon_raw;
+    manual_user_enter_context;
+    map_class;
+    map_decision;
+    map_perm;
+    matchmediacon;
+    matchpathcon;
+    matchpathcon_checkmatches;
+    matchpathcon_filespec_add;
+    matchpathcon_filespec_destroy;
+    matchpathcon_filespec_eval;
+    matchpathcon_fini;
+    matchpathcon_index;
+    matchpathcon_init;
+    matchpathcon_init_prefix;
+    mode_to_security_class;
+    myprintf_compat;
+    print_access_vector;
+    query_user_context;
+    realpath_not_final;
+    rpm_execcon;
+    security_av_perm_to_string;
+    security_av_string;
+    security_canonicalize_context;
+    security_canonicalize_context_raw;
+    security_check_context;
+    security_check_context_raw;
+    security_class_to_string;
+    security_commit_booleans;
+    security_compute_av;
+    security_compute_av_flags;
+    security_compute_av_flags_raw;
+    security_compute_av_raw;
+    security_compute_create;
+    security_compute_create_name;
+    security_compute_create_name_raw;
+    security_compute_create_raw;
+    security_compute_member;
+    security_compute_member_raw;
+    security_compute_relabel;
+    security_compute_relabel_raw;
+    security_compute_user;
+    security_compute_user_raw;
+    security_deny_unknown;
+    security_disable;
+    security_get_boolean_active;
+    security_get_boolean_names;
+    security_get_boolean_pending;
+    security_get_checkreqprot;
+    security_getenforce;
+    security_get_initial_context;
+    security_get_initial_context_raw;
+    security_load_booleans;
+    security_load_policy;
+    security_policyvers;
+    security_reject_unknown;
+    security_set_boolean;
+    security_set_boolean_list;
+    security_setenforce;
+    security_validatetrans;
+    security_validatetrans_raw;
+    selabel_close;
+    selabel_cmp;
+    selabel_digest;
+    selabel_get_digests_all_partial_matches;
+    selabel_hash_all_partial_matches;
+    selabel_lookup;
+    selabel_lookup_best_match;
+    selabel_lookup_best_match_raw;
+    selabel_lookup_raw;
+    selabel_open;
+    selabel_partial_match;
+    selabel_stats;
+    selinux_binary_policy_path;
+    selinux_booleans_path;
+    selinux_booleans_subs_path;
+    selinux_boolean_sub;
+    selinux_check_access;
+    selinux_check_passwd_access;
+    selinux_check_securetty_context;
+    selinux_colors_path;
+    selinux_contexts_path;
+    selinux_current_policy_path;
+    selinux_customizable_types_path;
+    selinux_default_context_path;
+    selinux_default_type_path;
+    selinux_failsafe_context_path;
+    selinux_file_context_cmp;
+    selinux_file_context_homedir_path;
+    selinux_file_context_local_path;
+    selinux_file_context_path;
+    selinux_file_context_subs_dist_path;
+    selinux_file_context_subs_path;
+    selinux_file_context_verify;
+    selinux_flush_class_cache;
+    selinuxfs_exists;
+    selinux_get_callback;
+    selinux_getenforcemode;
+    selinux_getpolicytype;
+    selinux_homedir_context_path;
+    selinux_init_load_policy;
+    selinux_lsetfilecon_default;
+    selinux_lxc_contexts_path;
+    selinux_media_context_path;
+    selinux_mkload_policy;
+    selinux_mnt;
+    selinux_netfilter_context_path;
+    selinux_openrc_contexts_path;
+    selinux_openssh_contexts_path;
+    selinux_path;
+    selinux_policy_root;
+    selinux_raw_context_to_color;
+    selinux_raw_to_trans_context;
+    selinux_removable_context_path;
+    selinux_reset_config;
+    selinux_restorecon;
+    selinux_restorecon_default_handle;
+    selinux_restorecon_set_alt_rootpath;
+    selinux_restorecon_set_exclude_list;
+    selinux_restorecon_set_sehandle;
+    selinux_restorecon_xattr;
+    selinux_securetty_types_path;
+    selinux_sepgsql_context_path;
+    selinux_set_callback;
+    selinux_set_mapping;
+    selinux_set_policy_root;
+    selinux_snapperd_contexts_path;
+    selinux_status_close;
+    selinux_status_deny_unknown;
+    selinux_status_getenforce;
+    selinux_status_open;
+    selinux_status_policyload;
+    selinux_status_updated;
+    selinux_systemd_contexts_path;
+    selinux_translations_path;
+    selinux_trans_to_raw_context;
+    selinux_user_contexts_path;
+    selinux_usersconf_path;
+    selinux_users_path;
+    selinux_virtual_domain_context_path;
+    selinux_virtual_image_context_path;
+    selinux_x_context_path;
+    setcon;
+    setcon_raw;
+    setexeccon;
+    setexeccon_raw;
+    setexecfilecon;
+    setfilecon;
+    setfilecon_raw;
+    setfscreatecon;
+    setfscreatecon_raw;
+    setkeycreatecon;
+    setkeycreatecon_raw;
+    set_matchpathcon_canoncon;
+    set_matchpathcon_flags;
+    set_matchpathcon_invalidcon;
+    set_matchpathcon_printf;
+    set_selinuxmnt;
+    setsockcreatecon;
+    setsockcreatecon_raw;
+    sidget;
+    sidput;
+    string_to_av_perm;
+    string_to_security_class;
+    unmap_class;
+    unmap_perm;
+  local:
+    *;
+};
-- 
2.17.1