WIFI-838: Dynamic discovery of HSPs/IDPs

Dynamically discover RADSEC endpoint based on NAPTR DNS records.

Signed-off-by: Arif Alam <arif.alam@netexperience.com>

feeds/wlan-ap/opensync/files/bin/dynamic_lookup.sh

@@ -0,0 +1,55 @@
+#! /bin/sh
+
+usage() {
+   echo "Usage: ${0} <realm>"
+   exit 1
+}
+
+test -n "${1}" || usage
+
+REALM="${1}"
+DIGCMD=$(command -v dig)
+PRINTCMD=$(command -v printf)
+
+validate_host() {
+         echo ${@} | tr -d '\n\t\r' | grep -E '^[_0-9a-zA-Z][-._0-9a-zA-Z]*$'
+}
+
+validate_port() {
+         echo ${@} | tr -d '\n\t\r' | grep -E '^[0-9]+$'
+}
+
+srv_lookup() {
+   ${DIGCMD} +short srv $SRV_HOST | sort -n -k1 |
+   while read line ; do
+      set $line ; PORT=$(validate_port $3) ; HOST=$(validate_host $4)
+      if [ -n "${HOST}" ] && [ -n "${PORT}" ]; then 
+         $PRINTCMD "\thost ${HOST%.}:${PORT}\n"
+      fi
+   done
+}
+
+naptr_lookup() {
+    ${DIGCMD} +short naptr ${REALM} | grep aaa+auth:radius.tls.tcp | sort -n -k1 |
+    while read line; do
+    set $line ; TYPE=$3 ; HOST=$6
+    if [ "$TYPE" = "\"s\"" -o "$TYPE" = "\"S\"" ]; then
+        SRV_HOST=${HOST%.}
+        srv_lookup
+    fi
+    done
+}
+
+if test -x "${DIGCMD}" ; then
+   SERVERS=$(naptr_lookup)
+else
+   echo "${0} requires \"dig\" command."
+   exit 1
+fi
+
+if test -n "${SERVERS}" ; then
+        $PRINTCMD "server dynamic_radsec.${REALM} {\n${SERVERS}\n\ttype TLS\n}\n"
+        exit 0
+fi
+
+exit 10				# No server found.

feeds/wlan-ap/opensync/patches/34-radsec-schema-consts.patch

@@ -1,6 +1,6 @@
 --- a/interfaces/opensync.ovsschema
 +++ b/interfaces/opensync.ovsschema
-@@ -9492,6 +9492,137 @@
+@@ -9493,6 +9493,146 @@
        },
        "isRoot": true,
        "maxRows": 1
@@ -25,6 +25,15 @@
 +                "max": 1
 +              }
 +            },
++            "auto_discover": {
++                "type": {
++                "key": {
++                  "type": "boolean"
++                },
++                "min": 1,
++                "max": 1
++              }
++            },
 +            "server": {
 +                "type": {
 +                "key": {

feeds/wlan-ap/opensync/src/platform/openwrt/src/lib/target/src/radius_proxy.c

@@ -55,6 +55,7 @@ enum {
 	RADIUS_PROXY_SERVER_STATUS,
 	RADIUS_PROXY_SERVER_TLS,
 	RADIUS_PROXY_SERVER_CERT_NAME_CHECK,
+	RADIUS_PROXY_SERVER_DYNAMIC_LOOKUP,
 	__RADIUS_PROXY_SERVER_MAX
 };
 
@@ -104,6 +105,7 @@ static const struct blobmsg_policy radius_proxy_server_policy[__RADIUS_PROXY_SER
 		[RADIUS_PROXY_SERVER_STATUS] = { .name = "statusServer", BLOBMSG_TYPE_BOOL },
 		[RADIUS_PROXY_SERVER_TLS] = { .name = "tls", BLOBMSG_TYPE_STRING },
 		[RADIUS_PROXY_SERVER_CERT_NAME_CHECK] = { .name = "certificateNameCheck", BLOBMSG_TYPE_BOOL },
+		[RADIUS_PROXY_SERVER_DYNAMIC_LOOKUP] = { .name = "dynamicLookupCommand", BLOBMSG_TYPE_STRING },
 };
 
 static const struct blobmsg_policy radius_proxy_realm_policy[__RADIUS_PROXY_REALM_MAX] = {
@@ -290,12 +292,19 @@ static bool radius_proxy_config_set(struct schema_Radius_Proxy_Config *conf)
 				"tls", uci_buf.head, &radius_proxy_tls_param, NULL);
 
 		blob_buf_init(&uci_buf, 0);
-		blobmsg_add_string(&uci_buf, "name", server_name);
+		if (conf->auto_discover)
+		{ /* auto discover radsec server address via realm DNS NAPTR record */
+			blobmsg_add_string(&uci_buf, "dynamicLookupCommand", "/bin/dynamic_lookup.sh");
+		}
+		else
+		{
 			blobmsg_add_string(&uci_buf, "host", conf->server);
-		blobmsg_add_string(&uci_buf, "type", "tls");
-		blobmsg_add_string(&uci_buf, "tls", tls_name);
 			blobmsg_add_u32(&uci_buf, "port", conf->port);
 			blobmsg_add_string(&uci_buf, "secret", "radsec");
+		}
+		blobmsg_add_string(&uci_buf, "name", server_name);
+		blobmsg_add_string(&uci_buf, "type", "tls");
+		blobmsg_add_string(&uci_buf, "tls", tls_name);
 		blobmsg_add_bool(&uci_buf, "statusServer", 0);
 		blobmsg_add_bool(&uci_buf, "certificateNameCheck", 0);
 		blob_to_uci_section(uci, "radsecproxy", server_name, "server",

profiles/wlan-ap.yml

@@ -82,6 +82,7 @@ packages:
   - radsecproxy
   - logrotate
   - kmod-ledtrig-heartbeat
+  - bind-dig
 
 diffconfig: |
   CONFIG_OPENSSL_ENGINE=y