gnrc_lorawan: encode LoRaWAN port in netif header

examples/gnrc_lorawan/Makefile

@@ -1,24 +1,37 @@
 # name of your application
 APPLICATION = gnrc_lorawan
 
-USEMODULE += shell
-USEMODULE += shell_commands
+# Turn on developer helpers
+DEVELHELP ?= 1
+
+BOARD ?= b-l072z-lrwan1
+RIOTBASE ?= ../../
+
+# Include board's default network devices and auto-initialization of GNRC
+# interfaces
 USEMODULE += gnrc_netdev_default
 USEMODULE += auto_init_gnrc_netif
+
+# Add support for GNRC LoRaWAN
 USEMODULE += gnrc_lorawan
+
+# Use GNRC pktdump to print downlink messages
 USEMODULE += gnrc_pktdump
-USEMODULE += gnrc_neterr
 
-BOARD ?= b-l072z-lrwan1
-RIOTBASE ?= ../../
+# Include the shell and shell commands.
+USEMODULE += shell
+USEMODULE += shell_commands
 
-# Turn on developer helpers
-DEVELHELP ?= 1
+# Use GNRC Txtsnd to transmit LoRaWAN from the shell
+USEMODULE += gnrc_txtsnd
 
-# use SX1276 by default
-DRIVER ?= sx1276
+# Uncomment as needed if a board doesn't include a LoRa radio by default
+# USEMODULE += sx1272
+# USEMODULE += sx1276
 
-USEMODULE += $(DRIVER)
+# As there is an 'app.config' we want to explicitly disable Kconfig by setting
+# the variable to empty
+SHOULD_RUN_KCONFIG ?=
 
 include $(RIOTBASE)/Makefile.include
 
@@ -33,6 +46,14 @@ include $(RIOTBASE)/Makefile.include
 # Check if being configured via Kconfig
 ifndef CONFIG_KCONFIG_USEMODULE_LORAWAN
 
+  # Tell GNRC to encode LoRaWAN port in the GNRC netif header.
+  # This allows us to use `gnrc_txtsnd` to send data from the shell using the
+  # `txtsnd` command.
+  #
+  # Note: From Release 22.01 all GNRC LoRaWAN packets will include the netif
+  # header. Therefore this flag will be removed after that
+  CFLAGS += -DCONFIG_GNRC_NETIF_LORAWAN_NETIF_HDR
+
   CFLAGS += -DCONFIG_LORAMAC_APP_KEY_DEFAULT=\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\"
   CFLAGS += -DCONFIG_LORAMAC_APP_EUI_DEFAULT=\"BBBBBBBBBBBBBBBB\"
   CFLAGS += -DCONFIG_LORAMAC_DEV_EUI_DEFAULT=\"CCCCCCCCCCCCCCCC\"

examples/gnrc_lorawan/README.md

@@ -15,7 +15,6 @@ Usage
 
 It's necessary to join the LoRaWAN network either via OTAA or ABP.
 All keys, addresses and EUIs are in network endian (big endian).
-The application listens to downlinks on Port 2 by default.
 Region need to be set in the Makefile.
 
 ## OTAA
@@ -73,10 +72,15 @@ CFLAGS += -DCONFIG_LORAMAC_DEV_ADDR_DEFAULT=\"FFFFFFFF\"
 
 ## Send data
 
-After join, send data using `send` command. E.g to send "Hello RIOT!" to port 2:
+After join, send data using `txtsnd` command:
+```
+txtsnd <if> <hex_port> <data>
+```
+
+E.g to send "Hello RIOT!" to LoRaWAN port 123 (hex 0x7B) via interface 3:
 
 ```
-send 3 "Hello RIOT!" 2
+txtsnd 3 7B "Hello RIOT!"
 ```
 
 ## Changing datarate of transmission
@@ -100,7 +104,7 @@ Send some data. The result of the Link Check request can be seen with
 
 ```
 ifconfig 3 link_check
-send 3 "Join the RIOT!"
+txtsnd 3 01 "Join the RIOT!"
 ```
 
 Check demodulation margin and number of gateways using `ifconfig`
@@ -124,18 +128,43 @@ E.g send confirmable messages:
 
 ```
 ifconfig 3 ack_req
-send 3 "My confirmable message"
+txtsnd 3 01 "My confirmable message"
 ```
 
 And unconfirmable messages:
 
 ```
 ifconfig 3 -ack_req
-send 3 "My unconfirmable message"
+txtsnd 3 01 "My unconfirmable message"
+```
+
+## Receiving data
+
+Schedule a downlink for the LoRaWAN node in the Application Server. If using
+TTN, this can be done under `Applications > <APP> > Devices > <DEV> > Overview`
+and then check the `Downlink` section.
+
+After sending data, the LoRaWAN Network Server will reply with the downlink
+data. For simplicity, this application is configured to dump downlink data to
+[GNRC pktdump](https://doc.riot-os.org/pktdump_8h.html).
+
+E.g:
 ```
+PKTDUMP: data received:
+~~ SNIP  0 - size:   2 byte, type: NETTYPE_UNDEF (0)
+00000000  AA  AA
+~~ SNIP  1 - size:   9 byte, type: NETTYPE_NETIF (-1)
+if_pid: 3  rssi: -32768  lqi: 0
+flags: 0x0
+src_l2addr: (nil)
+dst_l2addr: 01
+~~ PKT    -  2 snips, total size:  11 byte
+```
+
+This downlink was sent to port 1 (check `dst_l2addr` field)
 
 Current state and future plans
-============
+==============================
 
 The current GNRC LoRaWAN stack is still in an experimental state. It's still
 not compliant with the LoRaWAN specification because some features like duty

examples/gnrc_lorawan/app.config

@@ -0,0 +1,2 @@
+CONFIG_KCONFIG_USEMODULE_GNRC_NETIF=y
+CONFIG_GNRC_NETIF_LORAWAN_NETIF_HDR=y

examples/gnrc_lorawan/main.c

@@ -32,81 +32,23 @@
 #include "net/gnrc/netif.h"
 
 #include "net/gnrc/pktbuf.h"
-#include "net/gnrc/pktdump.h"
 #include "net/gnrc/netreg.h"
+#include "net/gnrc/pktdump.h"
 #include "net/loramac.h"
 
-#define LORAWAN_QUEUE_SIZE (4U)
-
-static void _usage(void)
-{
-    puts("usage: send <if_pid> <payload> [port]");
-}
-
-int tx_cmd(int argc, char **argv)
-{
-    gnrc_pktsnip_t *pkt;
-    uint8_t port = CONFIG_LORAMAC_DEFAULT_TX_PORT; /* Default: 2 */
-    int interface;
-
-    if (argc < 3) {
-        _usage();
-        return 1;
-    }
-
-    interface = atoi(argv[1]);
-    /* handle optional parameters */
-    if (argc > 3) {
-        port = atoi(argv[3]);
-        if (port == 0 || port >= 224) {
-            printf("error: invalid port given '%d', "
-                   "port can only be between 1 and 223\n", port);
-            return 1;
-        }
-    }
-
-    pkt = gnrc_pktbuf_add(NULL, argv[2], strlen(argv[2]), GNRC_NETTYPE_UNDEF);
-
-    /* register for returned packet status */
-    if (gnrc_neterr_reg(pkt) != 0) {
-        puts("Can not register for error reporting");
-        return 0;
-    }
-
-    gnrc_netapi_set(interface, NETOPT_LORAWAN_TX_PORT, 0, &port, sizeof(port));
-    gnrc_netif_send(gnrc_netif_get_by_pid(interface), pkt);
-
-    /* wait for packet status and check */
-    msg_t msg;
-    msg_receive(&msg);
-    if ((msg.type != GNRC_NETERR_MSG_TYPE) ||
-        (msg.content.value != GNRC_NETERR_SUCCESS)) {
-        printf("Error sending packet: (status: %d\n)", (int) msg.content.value);
-    }
-    else {
-        puts("Successfully sent packet");
-    }
-
-    return 0;
-}
-
-static const shell_command_t shell_commands[] = {
-    { "send",       "Send LoRaWAN data",     tx_cmd },
-    { NULL, NULL, NULL }
-};
-
-
 int main(void)
 {
     /* start the shell */
     puts("Initialization successful - starting the shell now");
-    gnrc_netreg_entry_t dump = GNRC_NETREG_ENTRY_INIT_PID(CONFIG_LORAMAC_DEFAULT_TX_PORT,
+
+    /* Receive LoRaWAN packets in GNRC pktdump */
+    gnrc_netreg_entry_t dump = GNRC_NETREG_ENTRY_INIT_PID(GNRC_NETREG_DEMUX_CTX_ALL,
                                                           gnrc_pktdump_pid);
 
-    gnrc_netreg_register(GNRC_NETTYPE_LORAWAN, &dump);
-    char line_buf[SHELL_DEFAULT_BUFSIZE];
+    gnrc_netreg_register(GNRC_NETTYPE_UNDEF, &dump);
 
-    shell_run(shell_commands, line_buf, SHELL_DEFAULT_BUFSIZE);
+    char line_buf[SHELL_DEFAULT_BUFSIZE];
+    shell_run(NULL, line_buf, SHELL_DEFAULT_BUFSIZE);
 
     return 0;
 }

sys/include/net/gnrc/netif/lorawan.h

@@ -29,6 +29,21 @@ extern "C" {
  */
 #define GNRC_NETIF_LORAWAN_FLAGS_LINK_CHECK                (0x1U)
 
+/**
+ * @brief Encode LoRaWAN port in GNRC netif header.
+ *
+ * When set, GNRC netif will interpret the destination address of the
+ * GNRC netif header as the LoRaWAN port. For downlinks, a GNRC netif header
+ * with the received port in destination field will be included in the
+ * first snip.
+ *
+ * @deprecated From Release 2021.10 all GNRC LoRaWAN packets will include
+ * the GNRC Netif header. Therefore this parameter will be removed
+ */
+#if defined(DOXYGEN)
+#define CONFIG_GNRC_NETIF_LORAWAN_NETIF_HDR
+#endif
+
 /**
  * @brief   GNRC LoRaWAN interface descriptor
  */

sys/include/net/netopt.h

@@ -640,6 +640,20 @@ typedef enum {
     /**
      * @brief   (uint8_t) LoRaWAN TX application port
      * - LoRaWAN: between 1 and 223 (included)
+     *
+     * @deprecated  This option is deprecated and will be removed in the
+     *              2022.01 Release.
+     *              The port is encoded now as a one byte
+     *              destination address in a @ref net_gnrc_netif_hdr snip
+     *              prepended in the packet.
+     *              The user must take care of prepending the required snip
+     *              during transmission. On reception, the
+     *              snip is prepended automatically by the stack and shall be
+     *              consumed by the user.
+     *              During the deprecation period it is required to
+     *              compile with @ref
+     *              CONFIG_GNRC_NETIF_LORAWAN_NETIF_HDR
+     *
      */
     NETOPT_LORAWAN_TX_PORT,
 

sys/net/gnrc/link_layer/lorawan/gnrc_lorawan_mcps.c

@@ -118,6 +118,11 @@ int gnrc_lorawan_parse_dl(gnrc_lorawan_t *mac, uint8_t *buf, size_t len,
             return -1;
         }
 
+        if (pkt->port > LORAMAC_PORT_MAX) {
+            DEBUG("gnrc_lorawan: packet with port > 223. Drop\n");
+            return -1;
+        }
+
         if (buf < p_mic) {
             pkt->enc_payload.iol_base = buf;
             pkt->enc_payload.iol_len = p_mic - buf;

sys/net/gnrc/netif/Kconfig

@@ -61,4 +61,17 @@ config GNRC_NETIF_PKTQ_TIMER_US
         Set to -1 to deactivate dequeing by timer. For this it has to be ensured
         that none of the notifications by the driver are missed!
 
+config GNRC_NETIF_LORAWAN_NETIF_HDR
+    bool "Encode LoRaWAN port in GNRC netif header"
+    depends on USEMODULE_GNRC_LORAWAN
+    help
+        When set, GNRC Netif will interpret
+        the destination address of the GNRC netif header as
+        the LoRaWAN port. For downlinks, a GNRC netif header
+        with the received port in destination field will be
+        included in the first snip. From Release 2021.10 all
+        GNRC LoRaWAN packets will include the GNRC Netif
+        header. Therefore this parameter will be removed
+
+
 endif # KCONFIG_USEMODULE_GNRC_NETIF