examples/gnrc_border_router: allow more than two ways to obtain a prefix

examples/gnrc_border_router/Makefile

@@ -44,17 +44,24 @@ USEMODULE += ps
 
 # When using a regular network uplink we should use DHCPv6
 ifneq (,$(filter cdc-ecm wifi ethernet,$(UPLINK)))
-  USE_DHCPV6 ?= 1
+  PREFIX_CONF ?= dhcpv6
 else
-  USE_DHCPV6 ?= 0
+  PREFIX_CONF ?= uhcp
 endif
 
-ifeq (1,$(USE_DHCPV6))
+# Check if the selected method for prefix configuration is valid
+ifeq (,$(filter dhcpv6 uhcp auto_subnets,$(PREFIX_CONF)))
+  $(error Supported methods for prefix configuration are `dhcpv6`, `uhcp` and `auto_subnets`)
+endif
+
+ifeq (dhcpv6,$(PREFIX_CONF))
   # include DHCPv6 client for 6LoWPAN border router
   USEMODULE += gnrc_dhcpv6_client_6lbr
-else
+else ifeq (uhcp,$(PREFIX_CONF))
   # include UHCP client
   USEMODULE += gnrc_uhcpc
+else ifeq (auto_subnets,$(PREFIX_CONF))
+  USEMODULE += gnrc_ipv6_auto_subnets_simple
 endif
 
 # Comment this out to disable code in RIOT that does safety checking
@@ -67,7 +74,7 @@ QUIET ?= 1
 
 # Ethos/native TAP interface and UHCP prefix can be configured from make command
 TAP ?= tap0
-ifeq (1,$(USE_DHCPV6))
+ifneq (,$(filter dhcpv6 auto_subnets,$(PREFIX_CONF)))
   # with DHCPv6 the 64-bit delegated prefixes are generated from a shorter
   # configured prefix.
   IPV6_PREFIX ?= 2001:db8::/32
@@ -110,7 +117,7 @@ include $(RIOTBASE)/Makefile.include
 
 # Compile-time configuration for DHCPv6 client (needs to come after
 # Makefile.include as this might come from Kconfig)
-ifeq (1,$(USE_DHCPV6))
+ifeq (dhcpv6,$(PREFIX_CONF))
   ifndef CONFIG_GNRC_DHCPV6_CLIENT_6LBR_STATIC_ROUTE
     ifeq (1,$(STATIC_ROUTES))
       CFLAGS += -DCONFIG_GNRC_DHCPV6_CLIENT_6LBR_STATIC_ROUTE=1
@@ -129,7 +136,7 @@ host-tools:
 
 # define native specific targets to only run UHCP daemon when required
 ifneq (,$(filter native,$(BOARD)))
-ifneq (1,$(USE_DHCPV6))
+ifeq (uhcp,$(PREFIX_CONF))
 .PHONY: uhcpd-daemon
 
 uhcpd-daemon: host-tools

examples/gnrc_border_router/Makefile.cdc-ecm.conf

@@ -2,11 +2,11 @@
 USEMODULE += auto_init_usbus
 USEMODULE += usbus_cdc_ecm
 
-ifeq (1,$(USE_DHCPV6))
+ifeq (dhcpv6, $(PREFIX_CONF))
   FLAGS_EXTRAS += --use-dhcpv6
 endif
 
 # Configure terminal parameters for UHCP
 TERMDEPS += host-tools
 TERMPROG ?= sudo sh $(RIOTTOOLS)/usb-cdc-ecm/start_network.sh
-TERMFLAGS ?= $(FLAGS_EXTRAS) $(IPV6_PREFIX) $(PORT)
+TERMFLAGS ?= $(FLAGS_EXTRAS) $(IPV6_PREFIX) $(PORT)

examples/gnrc_border_router/Makefile.ethos.conf

@@ -2,7 +2,7 @@ CFLAGS += -DETHOS_BAUDRATE=$(ETHOS_BAUDRATE)
 
 STATIC_ROUTES ?= 1
 
-ifeq (1,$(USE_DHCPV6))
+ifeq (dhcpv6, $(PREFIX_CONF))
   FLAGS_EXTRAS=--use-dhcpv6
 endif
 

examples/gnrc_border_router/Makefile.native.conf

@@ -9,7 +9,7 @@ CFLAGS += -DASYNC_READ_NUMOF=$(shell expr $(ZEP_DEVICES) + 1)
 # Set CFLAGS if not being set via Kconfig
 CFLAGS += $(if $(CONFIG_KCONFIG_MODULE_DHCPV6),,-DCONFIG_DHCPV6_CLIENT_PFX_LEASE_MAX=$(ZEP_DEVICES))
 
-ifeq (1,$(USE_DHCPV6))
+ifeq (dhcpv6,$(PREFIX_CONF))
   FLAGS_EXTRAS += --use-dhcpv6
 endif
 

examples/gnrc_border_router/Makefile.slip.conf

@@ -4,7 +4,7 @@ CFLAGS += -DSLIPDEV_PARAM_BAUDRATE=$(SLIP_BAUDRATE)
 
 STATIC_ROUTES ?= 1
 
-ifeq (1,$(USE_DHCPV6))
+ifeq (dhcpv6, $(PREFIX_CONF))
   FLAGS_EXTRAS=-d
 endif
 

examples/gnrc_border_router/README.md

@@ -36,7 +36,7 @@ router, stdio is multiplexed over the same line.
 
 The `wifi` uplink will connect to an existing WiFi (IEEE 802.11) network.
 The network must provide a DHCPv6 server that supports prefix delegation (IA_PD) when
-`USE_DHCPV6=1` is set (default).
+`PREFIX_CONF=dhcpv6` is set (default).
 
 Use `WIFI_SSID="SSID" WIFI_PASS="password"` in your `make` command to set your WiFi's
 credentials. You can alternatively edit the `Makefile`.
@@ -85,10 +85,10 @@ make clean all flash
 ```
 
 If you want to use DHCPv6 instead of UHCP compile with the environment variable
-`USE_DHCPV6` set to 1
+`PREFIX_CONF` set to dhcpv6
 
 ```bash
-USE_DHCPV6=1 make clean all flash
+PREFIX_CONF=dhcpv6 make clean all flash
 ```
 
 ## Usage