add mac_interface option

README.rst

@@ -61,6 +61,7 @@ UCI configuration options must go in ``/etc/config/openwisp``.
 - ``verify_ssl``: whether SSL verification must be performed or not, defaults to ``1``
 - ``shared_secret``: shared secret, needed for `Automatic registration`_
 - ``consistent_key``: whether `Consistent key generation`_ is enabled or not, defaults to ``1``
+- ``mac_interface``: which interface to use (if it exists) to catch the MAC address, defaults to ``eth0``
 - ``merge_config``: whether `Merge configuration`_ is enabled or not, defaults to ``1``
 - ``test_config``: whether a new configuration must be tested before being considered applied, defaults to ``1``
 - ``test_script``: custom test script, read more about this feature in `Configuration test`_
@@ -94,6 +95,9 @@ even if reset or reflashed.
 The ``key`` is generated consistently with an operation like ``md5sum(mac_address + shared_secret)``;
 this allows the controller application to recognize that an existing device is registering itself again.
 
+Verify that the interface of which you take the mac address is always the same with the mac_interface option.
+Pay attention on virtual interface like bridges and taps.
+
 This feature is enabled by default, but must be enabled also in the controller application
 in order to work.
 

openwisp-config/files/openwisp-nossl.config

@@ -7,6 +7,7 @@ config controller 'http'
 	option verify_ssl '0'
 	#option shared_secret ''
 	#option consistent_key '1'
+	#option mac_interface 'eth0'
 	#option merge_config '1'
 	#option test_config '1'
 	#option test_script '/usr/sbin/mytest'

openwisp-config/files/openwisp-ssl.config

@@ -7,6 +7,7 @@ config controller 'http'
 	#option verify_ssl '1'
 	#option shared_secret ''
 	#option consistent_key '1'
+	#option mac_interface 'eth0'
 	#option merge_config '1'
 	#option test_config '1'
 	#option test_script '/usr/sbin/mytest'

openwisp-config/files/openwisp.agent

@@ -11,6 +11,7 @@ while [ -n "$1" ]; do
 		--key) export KEY="$2"; shift;;
 		--shared-secret) export SHARED_SECRET="$2"; shift;;
 		--consistent-key) export CONSISTENT_KEY="$2"; shift;;
+		--mac-interface) export MAC_INTERFACE="$2"; shift;;
 		--merge-config) export MERGE_CONFIG="$2"; shift;;
 		--unmanaged) export UNMANAGED="$2"; shift;;
 		--test-config) export TEST_CONFIG="$2"; shift;;
@@ -52,6 +53,7 @@ VERIFY_SSL=${VERIFY_SSL:-1}
 MERGE_CONFIG=${MERGE_CONFIG:-1}
 TEST_CONFIG=${TEST_CONFIG:-1}
 CONSISTENT_KEY=${CONSISTENT_KEY:-1}
+MAC_INTERFACE=${MAC_INTERFACE:-eth0}
 CONNECT_TIMEOUT=${CONNECT_TIMEOUT:-15}
 MAX_TIME=${MAX_TIME:-30}
 CAPATH=${CAPATH:-/etc/ssl/certs}
@@ -97,10 +99,10 @@ register() {
 		   -p daemon.info
 	local hostname=$(uci get system.@system[0].hostname)
 	# use macaddr of eth0 or fallback to first non-loopback interface
-	local raw=$(ifconfig eth0 2&> /dev/null)
+	local raw=$(ifconfig $MAC_INTERFACE 2&> /dev/null)
 	if [ -z "$raw" ]; then raw=$(ifconfig); fi
-	local macaddr=$(echo "$raw " | grep -v lo | grep HWaddr | awk '/HWaddr/ { print $5 }' | head -n 1)
-	# use macaddress if hostname has not been changed
+	local macaddr=$(echo "$raw " | egrep -v "^(lo|br-|tap[0-9]+)" | awk '/HWaddr/ { print $5 }' | head -n 1)
+	# use macaddress if hostname is the default one or empty 
 	if [ "$hostname" == "OpenWrt" ] || [ "$hostname" == "lede" ] || [ -z "$hostname" ]; then
 		hostname="$macaddr"
 	fi

openwisp-config/files/openwisp.init

@@ -15,6 +15,7 @@ start_service() {
 	key=$(config_get http key)
 	shared_secret=$(config_get http shared_secret)
 	consistent_key=$(config_get http consistent_key)
+	mac_interface=$(config_get http mac_interface)
 	unmanaged=$(config_get http unmanaged)
 	merge_config=$(config_get http merge_config)
 	test_config=$(config_get http test_config)
@@ -29,6 +30,7 @@ start_service() {
 	if [ $key ]; then key="--key $key"; fi
 	if [ $shared_secret ]; then shared_secret="--shared-secret $shared_secret"; fi
 	if [ $consistent_key ]; then consistent_key="--consistent-key $consistent_key"; fi
+	if [ $mac_interface ]; then mac_interface="--mac-interface $mac_interface"; fi
 	if [ -n "$unmanaged" ]; then
 		# replace spaces with commas to avoid problems when
 		# passing this arg to procd_set_param command
@@ -58,7 +60,7 @@ start_service() {
 
 	procd_open_instance
 	procd_set_param command $PROG $url $interval $verify_ssl $uuid $key $shared_secret \
-	                        $consistent_key $unmanaged $merge_config $test_config \
+	                        $consistent_key $mac_interface $unmanaged $merge_config $test_config \
 	                        $test_script $connect_timeout $max_time $capath
 	procd_set_param respawn
 	procd_close_instance