diff --git a/lib/libifconfig/Makefile b/lib/libifconfig/Makefile
--- a/lib/libifconfig/Makefile
+++ b/lib/libifconfig/Makefile
@@ -8,6 +8,10 @@
 
 SHLIBDIR?=	/lib
 SHLIB_MAJOR=	1
+
+VERSION_DEF=	${LIBCSRCDIR}/Versions.def
+SYMBOL_MAPS=	${.CURDIR}/Symbol.map
+
 SRCS=		libifconfig.c \
 		libifconfig_bridge.c \
 		libifconfig_carp.c \
diff --git a/lib/libifconfig/Symbol.map b/lib/libifconfig/Symbol.map
new file mode 100644
--- /dev/null
+++ b/lib/libifconfig/Symbol.map
@@ -0,0 +1,74 @@
+FBSD_1.6 {
+	ifconfig_bridge_get_bridge_status;
+	ifconfig_bridge_free_bridge_status;
+	ifconfig_carp_get_info;
+	ifconfig_close;
+	ifconfig_create_interface;
+	ifconfig_create_interface_vlan;
+	ifconfig_destroy_interface;
+	ifconfig_err_errno;
+	ifconfig_err_errtype;
+	ifconfig_err_ioctlreq;
+	ifconfig_foreach_ifaddr;
+	ifconfig_foreach_interface;
+	ifconfig_get_capability;
+	ifconfig_get_description;
+	ifconfig_get_fib;
+	ifconfig_get_groups;
+	ifconfig_get_ifstatus;
+	ifconfig_get_metric;
+	ifconfig_get_mtu;
+	ifconfig_get_nd6;
+	ifconfig_get_orig_name;
+	ifconfig_inet_get_addrinfo;
+	ifconfig_inet6_get_addrinfo;
+	ifconfig_lagg_free_lagg_status;
+	ifconfig_lagg_get_lagg_status;
+	ifconfig_lagg_get_laggport_status;
+	ifconfig_list_cloners;
+	ifconfig_media_get_mediareq;
+	ifconfig_media_get_options_string;
+	ifconfig_media_get_status;
+	ifconfig_media_get_subtype;
+	ifconfig_media_get_type;
+	ifconfig_open;
+	ifconfig_set_capability;
+	ifconfig_set_description;
+	ifconfig_set_fib;
+	ifconfig_set_metric;
+	ifconfig_set_mtu;
+	ifconfig_set_name;
+	ifconfig_set_vlantag;
+	ifconfig_sfp_channel_count;
+	ifconfig_sfp_dump_region_count;
+	ifconfig_sfp_free_sfp_status;
+	ifconfig_sfp_get_sfp_dump;
+	ifconfig_sfp_get_sfp_info;
+	ifconfig_sfp_get_sfp_info_strings;
+	ifconfig_sfp_get_sfp_status;
+	ifconfig_sfp_get_sfp_vendor_info;
+	ifconfig_sfp_physical_spec;
+	ifconfig_unset_description;
+
+	bias_mA;
+	power_dBm;
+	power_mW;
+
+	/* Auto-generated. */
+	ifconfig_sfp_cab_tech_description;
+	ifconfig_sfp_cab_tech_symbol;
+	ifconfig_sfp_conn_description;
+	ifconfig_sfp_conn_symbol;
+	ifconfig_sfp_eth_10g_description;
+	ifconfig_sfp_eth_10g_symbol;
+	ifconfig_sfp_eth_1040g_description;
+	ifconfig_sfp_eth_1040g_symbol;
+	ifconfig_sfp_eth_description;
+	ifconfig_sfp_eth_symbol;
+	ifconfig_sfp_eth_ext_description;
+	ifconfig_sfp_eth_ext_symbol;
+	ifconfig_sfp_fc_speed_description;
+	ifconfig_sfp_fc_speed_symbol;
+	ifconfig_sfp_rev_description;
+	ifconfig_sfp_rev_symbol;
+};