diff mbox series

[V4,5/6] net: maclorawan: Implement maclorawan class module

Message ID 20181204141341.4353-6-starnight@g.ncu.edu.tw (mailing list archive)
State New, archived
Headers show
Series [V4,1/6] net: lorawan: Add LoRaWAN socket module | expand

Commit Message

Jian-Hong Pan Dec. 4, 2018, 2:13 p.m. UTC
LoRaWAN defined by LoRa Alliance(TM) is the MAC layer over LoRa devices.

This patch implements part of Class A end-devices SoftMAC defined in
LoRaWAN(TM) Specification Ver. 1.0.2:
1. End-device receive slot timing
2. Only single channel and single data rate for now
3. Unconfirmed data up/down message types

On the other side, it defines the basic interface and operation
functions for compatible LoRa device drivers.

Signed-off-by: Jian-Hong Pan <starnight@g.ncu.edu.tw>
---
V2:
- Split the LoRaWAN class module patch in V1 into LoRaWAN socket and
  LoRaWAN Soft MAC modules
- Modify for Big/Little-Endian
- Use SPDX license identifiers

V3:
- Remove the decoration word - inline of the functions
- Order local variables from longest to shortest line in the functions
- Change the calling mac_cb function to lrw_get_mac_cb macro

V4:
- Fix the delay period between RX window#1 and window#2
- Fix by coding style report from scripts/checkpatch.pl

 net/maclorawan/Kconfig  |  14 +
 net/maclorawan/Makefile |   2 +
 net/maclorawan/mac.c    | 518 ++++++++++++++++++++++++++++++++++
 net/maclorawan/main.c   | 605 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 1139 insertions(+)
 create mode 100644 net/maclorawan/Kconfig
 create mode 100644 net/maclorawan/Makefile
 create mode 100644 net/maclorawan/mac.c
 create mode 100644 net/maclorawan/main.c

Comments

Alan Cox Dec. 4, 2018, 8:45 p.m. UTC | #1
> +void
> +lrw_parse_frame(struct lrw_session *ss, struct sk_buff *skb)
> +{
> +	struct lrw_fhdr *fhdr = &ss->rx_fhdr;
> +	__le16 *p_fcnt;
> +
> +	pr_debug("%s: %s\n", LORAWAN_MODULE_NAME, __func__);
> +
> +	/* Get message type */
> +	fhdr->mtype = skb->data[0];
> +	skb_pull(skb, LRW_MHDR_LEN);

This does not seem robust. There is no point at which you actually check
the message size is valid etc

> +	fhdr->fopts_len = fhdr->fctrl & 0xF;
> +	if (fhdr->fopts_len > 0) {
> +		memcpy(fhdr->fopts, skb->data, fhdr->fopts_len);
> +		skb_pull(skb, fhdr->fopts_len);
> +	}

In fact you appear to copy random kernel memory into a buffer
> +
> +	/* TODO: Parse frame options */
> +
> +	/* Remove message integrity code */
> +	skb_trim(skb, skb->len - LRW_MIC_LEN);

and then try and trim the buffer to a negative size ?

Alan
Jian-Hong Pan Dec. 9, 2018, 8:27 a.m. UTC | #2
I made a fake skb and passed it to lrw_parse_frame() function for
testing.  I use print_hex_dump() function to show the skb's content.
Here is the original content in the skb->data and the length is 20 bytes.

[   33.732033] 00000000: 40 04 03 02 01 00 00 00 00 27 76 d3 2d 1b 79
a0  @........'v.-.y.
[   33.732065] 00000010: 18 38 fb a6                                      .8..

Byte 0: MHDR field, value is 0x40.
Byte 1 ~ 4: DevAddr field, value is 0x04 0x03 0x02 0x01.
Byte 5: FCtrl field, value is 0x00.
Byte 6 ~ 7: FCnt field, value is 0x00 0x00.
Byte 8: FPort field, value is 0x00.
Byte 9 ~ 15: Encrypted payload
Byte 16 ~ 19: MIC field value is 0x18 0x38 0xfb 0xa6.

> > +void
> > +lrw_parse_frame(struct lrw_session *ss, struct sk_buff *skb)
> > +{
> > +     struct lrw_fhdr *fhdr = &ss->rx_fhdr;
> > +     __le16 *p_fcnt;
> > +
> > +     pr_debug("%s: %s\n", LORAWAN_MODULE_NAME, __func__);
> > +
> > +     /* Get message type */
> > +     fhdr->mtype = skb->data[0];
> > +     skb_pull(skb, LRW_MHDR_LEN);

print_hex_dump skb here:
[   33.732202] 00000000: 04 03 02 01 00 00 00 00 27 76 d3 2d 1b 79 a0
18  ........'v.-.y..
[   33.732204] 00000010: 38 fb a6

> This does not seem robust. There is no point at which you actually check
> the message size is valid etc

Thanks!  It is a potential bug.
It should check skb->len >= length of MHDR + DevAddr + FCtrl + FCnt + MIC.
These are required fields for (Un)confirmed Data Up/Down messages.


print_hex_dump skb here:
[   33.732211] 00000000: 00 27 76 d3 2d 1b 79 a0 18 38 fb a6
   .'v.-.y..8..

> > +     fhdr->fopts_len = fhdr->fctrl & 0xF;
> > +     if (fhdr->fopts_len > 0) {
> > +             memcpy(fhdr->fopts, skb->data, fhdr->fopts_len);
> > +             skb_pull(skb, fhdr->fopts_len);
> > +     }

print_hex_dump skb here:
[   33.732213] 00000000: 00 27 76 d3 2d 1b 79 a0 18 38 fb a6
   .'v.-.y..8..

> In fact you appear to copy random kernel memory into a buffer

It copied fhdr->fopts_len bytes from skb->data to fhdr->fopts if
fhdr->fopts_len > 0.
https://www.kernel.org/doc/html/latest/core-api/kernel-api.html?highlight=memcpy#c.memcpy

> > +
> > +     /* TODO: Parse frame options */
> > +
> > +     /* Remove message integrity code */
> > +     skb_trim(skb, skb->len - LRW_MIC_LEN);

print_hex_dump skb here:
[   33.732216] 00000000: 00 27 76 d3 2d 1b 79 a0
   .'v.-.y.

> and then try and trim the buffer to a negative size ?

It removed 4 tail bytes (MIC).  (skb->len - LRW_MIC_LEN) is the final
new length as skb_trim()'s 2nd argument len.
https://www.kernel.org/doc/html/latest/networking/kapi.html?highlight=skb_trim#c.skb_trim

I found another bug which did not initialize rx_skb_list.  So,
lrw_parse_frame() may be passed a mystery skb.

Please keep reviewing.  That is appreciated.

Thank you,
Jian-Hong Pan
Jian-Hong Pan Dec. 16, 2018, 10:18 a.m. UTC | #3
LoRaWAN(TM) is the MAC layer defined by LoRa Alliance(TM) over LoRa
devices.  LoRa is one of Low-Power Wide-Area Network (LPWAN) technology.

LoRaWAN networks typically are laid out in a star-of-stars topology in
which gateways relay messages between end-devices and a central network
server at the backend.  Gateways are connected to the network server via
standard IP connections while end-devices use single hop LoRa(TM) or FSK
communication to one or many gateways.

A LoRa network distinguishes between a basic LoRaWAN (named Class A) and
optional features (Class B, Class C ...):
* Bi-directional end-devices (Class A)
* Bi-directional end-devices with scheduled receive slots (Class B)
* Bi-directional end-devices with maximal receive slots (Class C)

This patch set add LoRaWAN class module implementing the stack,
especially the soft MAC, between socket APIs and LoRa device drivers.

socket APIs:
send and receive the data
------------------------------------------------------------------------
LoRaWAN class module implements soft MAC:
append the header/footer, encryption/decryption, timing slot and MAC
commands
------------------------------------------------------------------------
LoRa device drivers:
send and receive the messages for MAC layer
------------------------------------------------------------------------
LoRa devices

This module starts from simple and implements partial Class A
end-devices features defined in LoRaWAN(TM) Specification Ver. 1.0.2.
More features and complexity, for example regional parameters, confirmed
data messages, join request/accept messages for Over-The-Air Activation,
MAC commands ... will be added in the future.

Jian-Hong Pan (6):
  net: lorawan: Add LoRaWAN socket module
  net: lorawan: Add LoRaWAN API declaration for LoRa devices
  net: maclorawan: Add maclorawan module declaration
  net: maclorawan: Implement the crypto of maclorawan module
  net: maclorawan: Implement maclorawan class module
  net: lorawan: List LORAWAN in menuconfig

 include/linux/lora/lorawan.h        | 131 ++++++
 include/linux/lora/lorawan_netdev.h |  52 +++
 net/Kconfig                         |   2 +
 net/Makefile                        |   2 +
 net/lorawan/Kconfig                 |  10 +
 net/lorawan/Makefile                |   2 +
 net/lorawan/socket.c                | 686 ++++++++++++++++++++++++++++
 net/maclorawan/Kconfig              |  14 +
 net/maclorawan/Makefile             |   2 +
 net/maclorawan/crypto.c             | 212 +++++++++
 net/maclorawan/crypto.h             |  27 ++
 net/maclorawan/mac.c                | 555 ++++++++++++++++++++++
 net/maclorawan/maclorawan.h         | 202 ++++++++
 net/maclorawan/main.c               | 606 ++++++++++++++++++++++++
 14 files changed, 2503 insertions(+)
 create mode 100644 include/linux/lora/lorawan.h
 create mode 100644 include/linux/lora/lorawan_netdev.h
 create mode 100644 net/lorawan/Kconfig
 create mode 100644 net/lorawan/Makefile
 create mode 100644 net/lorawan/socket.c
 create mode 100644 net/maclorawan/Kconfig
 create mode 100644 net/maclorawan/Makefile
 create mode 100644 net/maclorawan/crypto.c
 create mode 100644 net/maclorawan/crypto.h
 create mode 100644 net/maclorawan/mac.c
 create mode 100644 net/maclorawan/maclorawan.h
 create mode 100644 net/maclorawan/main.c
Jiri Pirko Dec. 17, 2018, 1:51 p.m. UTC | #4
Sun, Dec 16, 2018 at 11:18:53AM CET, starnight@g.ncu.edu.tw wrote:
>LoRaWAN(TM) is the MAC layer defined by LoRa Alliance(TM) over LoRa
>devices.  LoRa is one of Low-Power Wide-Area Network (LPWAN) technology.
>
>LoRaWAN networks typically are laid out in a star-of-stars topology in
>which gateways relay messages between end-devices and a central network
>server at the backend.  Gateways are connected to the network server via
>standard IP connections while end-devices use single hop LoRa(TM) or FSK
>communication to one or many gateways.
>
>A LoRa network distinguishes between a basic LoRaWAN (named Class A) and
>optional features (Class B, Class C ...):
>* Bi-directional end-devices (Class A)
>* Bi-directional end-devices with scheduled receive slots (Class B)
>* Bi-directional end-devices with maximal receive slots (Class C)
>
>This patch set add LoRaWAN class module implementing the stack,
>especially the soft MAC, between socket APIs and LoRa device drivers.
>
>socket APIs:
>send and receive the data
>------------------------------------------------------------------------
>LoRaWAN class module implements soft MAC:
>append the header/footer, encryption/decryption, timing slot and MAC
>commands
>------------------------------------------------------------------------
>LoRa device drivers:
>send and receive the messages for MAC layer
>------------------------------------------------------------------------
>LoRa devices
>
>This module starts from simple and implements partial Class A
>end-devices features defined in LoRaWAN(TM) Specification Ver. 1.0.2.
>More features and complexity, for example regional parameters, confirmed
>data messages, join request/accept messages for Over-The-Air Activation,
>MAC commands ... will be added in the future.

Could you please send new patchset versions as separate patchsets? It is
messy to have all versions in one thread. Also, please send it so the
patches are in-reply-to the cover letter (git-send-email default).

Thanks!
diff mbox series

Patch

diff --git a/net/maclorawan/Kconfig b/net/maclorawan/Kconfig
new file mode 100644
index 000000000000..d700314edf26
--- /dev/null
+++ b/net/maclorawan/Kconfig
@@ -0,0 +1,14 @@ 
+config MACLORAWAN
+	tristate "Generic LoRaWAN Soft Networking Stack (maclorawan)"
+	depends on LORAWAN
+	select CRYPTO
+	select CRYPTO_CMAC
+	select CRYPTO_CBC
+	select CRYPTO_AES
+	help
+	  This option enables the hardware independent LoRaWAN
+	  networking stack for SoftMAC devices (the ones implementing
+	  only PHY level of LoRa standard).
+
+	  If you plan to use HardMAC LoRaWAN devices, you can say N
+	  here.  Alternatively you can say M to compile it as a module.
diff --git a/net/maclorawan/Makefile b/net/maclorawan/Makefile
new file mode 100644
index 000000000000..562831e66c82
--- /dev/null
+++ b/net/maclorawan/Makefile
@@ -0,0 +1,2 @@ 
+obj-$(CONFIG_MACLORAWAN)	+= maclorawan.o
+maclorawan-objs			:= main.o mac.o crypto.o
diff --git a/net/maclorawan/mac.c b/net/maclorawan/mac.c
new file mode 100644
index 000000000000..70e6923bf63e
--- /dev/null
+++ b/net/maclorawan/mac.c
@@ -0,0 +1,518 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause
+/*-
+ * LoRaWAN soft MAC
+ *
+ * Copyright (c) 2018 Jian-Hong, Pan <starnight@g.ncu.edu.tw>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/poll.h>
+#include <linux/uaccess.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/lora/lorawan.h>
+#include <linux/lora/lorawan_netdev.h>
+
+#include "maclorawan.h"
+#include "crypto.h"
+
+static void rx_timeout_work(struct work_struct *work);
+
+struct lrw_session *
+lrw_alloc_ss(struct lrw_struct *lrw_st)
+{
+	struct lrw_session *ss;
+
+	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
+	if (!ss)
+		goto lrw_alloc_ss_end;
+
+	ss->lrw_st = lrw_st;
+	ss->devaddr = lrw_st->devaddr;
+	INIT_LIST_HEAD(&ss->entry);
+
+	ss->tx_should_ack = false;
+	ss->retry = 3;
+	spin_lock_init(&ss->state_lock);
+	INIT_WORK(&ss->timeout_work, rx_timeout_work);
+
+lrw_alloc_ss_end:
+	return ss;
+}
+
+void
+lrw_free_ss(struct lrw_session *ss)
+{
+	netdev_dbg(ss->lrw_st->ndev, "%s\n", __func__);
+	if (ss->tx_skb)
+		consume_skb(ss->tx_skb);
+	netdev_dbg(ss->lrw_st->ndev, "%s: free rx skb\n", __func__);
+	if (ss->rx_skb)
+		consume_skb(ss->rx_skb);
+
+	netdev_dbg(ss->lrw_st->ndev, "%s: free ss\n", __func__);
+	kfree(ss);
+}
+
+void
+lrw_del_ss(struct lrw_session *ss)
+{
+	netdev_dbg(ss->lrw_st->ndev, "%s\n", __func__);
+	list_del(&ss->entry);
+	lrw_free_ss(ss);
+}
+
+void
+lrw_del_all_ss(struct lrw_struct *lrw_st)
+{
+	struct lrw_session *ss, *tmp;
+
+	mutex_lock(&lrw_st->ss_list_lock);
+	lrw_st->_cur_ss = NULL;
+	list_for_each_entry_safe(ss, tmp, &lrw_st->ss_list, entry) {
+		del_timer(&ss->timer);
+		lrw_del_ss(ss);
+	}
+	mutex_unlock(&lrw_st->ss_list_lock);
+}
+
+void
+lrw_ready_hw(struct lrw_struct *lrw_st)
+{
+	lrw_st->state = LRW_STATE_IDLE;
+}
+
+int
+lrw_start_hw(struct lrw_struct *lrw_st)
+{
+	int ret = 0;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+	lrw_st->nwks_shash_tfm = lrw_mic_key_setup(lrw_st->nwkskey,
+						   LRW_KEY_LEN);
+	lrw_st->nwks_skc_tfm = lrw_encrypt_key_setup(lrw_st->nwkskey,
+						     LRW_KEY_LEN);
+	lrw_st->apps_skc_tfm = lrw_encrypt_key_setup(lrw_st->appskey,
+						     LRW_KEY_LEN);
+	lrw_st->state = LRW_START;
+	ret = lrw_st->ops->start(&lrw_st->hw);
+	if (!ret)
+		lrw_ready_hw(lrw_st);
+
+	return ret;
+}
+
+void
+lrw_stop_hw(struct lrw_struct *lrw_st)
+{
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+	lrw_st->state = LRW_STOP;
+	netdev_dbg(lrw_st->ndev, "%s: going to stop hardware\n", __func__);
+	lrw_st->ops->stop(&lrw_st->hw);
+
+	netdev_dbg(lrw_st->ndev, "%s: going to kill tasks & flush works",
+		   __func__);
+	tasklet_kill(&lrw_st->xmit_task);
+	flush_work(&lrw_st->rx_work);
+
+	netdev_dbg(lrw_st->ndev, "%s: going to delete all session\n", __func__);
+	lrw_del_all_ss(lrw_st);
+
+	netdev_dbg(lrw_st->ndev, "%s: going to free mic tfm\n", __func__);
+	lrw_mic_key_free(lrw_st->nwks_shash_tfm);
+	netdev_dbg(lrw_st->ndev, "%s: going to free nwks tfm\n", __func__);
+	lrw_encrypt_key_free(lrw_st->nwks_skc_tfm);
+	netdev_dbg(lrw_st->ndev, "%s: going to free apps tfm\n", __func__);
+	lrw_encrypt_key_free(lrw_st->apps_skc_tfm);
+}
+
+void
+lrw_prepare_tx_frame(struct lrw_session *ss)
+{
+	struct lrw_struct *lrw_st = ss->lrw_st;
+	struct sk_buff *skb = ss->tx_skb;
+	u8 mhdr, fctrl, fport, mic[4];
+	__le32 le_devaddr;
+	__le16 le_fcnt_up;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	/* Encrypt the plain buffer content */
+	lrw_encrypt_buf(lrw_st->apps_skc_tfm, LRW_UPLINK,
+			ss->devaddr, ss->fcnt_up, skb->data, skb->len);
+
+	/* Push FPort */
+	if (skb->len) {
+		fport = ss->fport;
+		memcpy(skb_push(skb, LRW_FPORT_LEN), &fport, LRW_FPORT_LEN);
+	}
+
+	/* Push FCnt_Up */
+	le_fcnt_up = cpu_to_le16(ss->fcnt_up);
+	memcpy(skb_push(skb, 2), &le_fcnt_up, 2);
+
+	/* Push FCtrl */
+	fctrl = 0;
+	if (lrw_st->rx_should_ack) {
+		fctrl |= 0x20;
+		lrw_st->rx_should_ack = false;
+	}
+	memcpy(skb_push(skb, 1), &fctrl, 1);
+
+	/* Push DevAddr */
+	le_devaddr = cpu_to_le32(ss->devaddr);
+	memcpy(skb_push(skb, LRW_DEVADDR_LEN), &le_devaddr, LRW_DEVADDR_LEN);
+
+	/* Push MHDR */
+	mhdr = LRW_UNCONFIRMED_DATA_UP << 5;
+	if ((mhdr & (0x6 << 5)) == (0x4 << 5))
+		ss->tx_should_ack = true;
+	memcpy(skb_push(skb, LRW_MHDR_LEN), &mhdr, LRW_MHDR_LEN);
+
+	/* Put MIC */
+	lrw_calc_mic(lrw_st->nwks_shash_tfm, LRW_UPLINK,
+		     ss->devaddr, ss->fcnt_up, skb->data, skb->len, mic);
+	memcpy(skb_put(skb, LRW_MIC_LEN), mic, LRW_MIC_LEN);
+}
+
+void
+lrw_xmit(unsigned long data)
+{
+	struct lrw_struct *lrw_st = (struct lrw_struct *)data;
+	struct lrw_session *ss = lrw_st->_cur_ss;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+	ss->state = LRW_XMITTING_SS;
+	lrw_st->ops->xmit_async(&lrw_st->hw, ss->tx_skb);
+}
+
+void
+lrw_parse_frame(struct lrw_session *ss, struct sk_buff *skb)
+{
+	struct lrw_fhdr *fhdr = &ss->rx_fhdr;
+	__le16 *p_fcnt;
+
+	pr_debug("%s: %s\n", LORAWAN_MODULE_NAME, __func__);
+
+	/* Get message type */
+	fhdr->mtype = skb->data[0];
+	skb_pull(skb, LRW_MHDR_LEN);
+
+	/* Trim Device Address */
+	skb_pull(skb, 4);
+
+	/* Get frame control */
+	fhdr->fctrl = skb->data[0];
+	skb_pull(skb, 1);
+
+	/* Ack the original TX frame if it should be acked */
+	if (ss->tx_should_ack && (fhdr->fctrl & 0x20))
+		ss->tx_should_ack = false;
+
+	/* Get frame count */
+	p_fcnt = (__le16 *)skb->data;
+	fhdr->fcnt = le16_to_cpu(*p_fcnt);
+	skb_pull(skb, 2);
+
+	/* Get frame options */
+	fhdr->fopts_len = fhdr->fctrl & 0xF;
+	if (fhdr->fopts_len > 0) {
+		memcpy(fhdr->fopts, skb->data, fhdr->fopts_len);
+		skb_pull(skb, fhdr->fopts_len);
+	}
+
+	/* TODO: Parse frame options */
+
+	/* Remove message integrity code */
+	skb_trim(skb, skb->len - LRW_MIC_LEN);
+}
+
+struct lrw_session *
+lrw_rx_skb_2_session(struct lrw_struct *lrw_st, struct sk_buff *rx_skb)
+{
+	struct lrw_session *ss;
+	__le16 *p_fcnt;
+	u16 fcnt;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	p_fcnt = (__le16 *)(rx_skb->data + 6);
+	fcnt = le16_to_cpu(*p_fcnt);
+
+	/* Find the corresponding session */
+	ss = lrw_st->_cur_ss;
+
+	/* Frame count downlink check */
+	if (fcnt >= (ss->fcnt_down & 0xFFFF))
+		ss->rx_skb = rx_skb;
+	else
+		ss = NULL;
+
+	return ss;
+}
+
+void
+lrw_rx_work(struct work_struct *work)
+{
+	struct lrw_struct *lrw_st;
+	struct lrw_session *ss;
+	struct sk_buff *skb;
+
+	lrw_st = container_of(work, struct lrw_struct, rx_work);
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	skb = lrw_st->rx_skb_list.next;
+	skb_dequeue(&lrw_st->rx_skb_list);
+
+	/* Check and parse the RX frame */
+	ss = lrw_rx_skb_2_session(lrw_st, skb);
+	if (!ss)
+		goto lrw_rx_work_not_new_frame;
+
+	lrw_parse_frame(ss, skb);
+
+	/* Check the TX frame is acked or not */
+	if (ss->tx_should_ack) {
+		ss->rx_skb = NULL;
+		goto lrw_rx_work_not_new_frame;
+	}
+
+	/* The TX frame is acked or no need to be acked */
+	del_timer(&ss->timer);
+	lrw_st->rx_should_ack = (ss->rx_fhdr.mtype & 0xC0) == 0x40;
+
+	lrw_st->ndev->stats.rx_packets++;
+	lrw_st->ndev->stats.rx_bytes += ss->rx_skb->len;
+
+	if (ss->rx_skb->len > 0) {
+		spin_lock_bh(&ss->state_lock);
+		ss->state = LRW_RXRECEIVED_SS;
+		spin_unlock_bh(&ss->state_lock);
+
+		lrw_get_mac_cb(skb)->devaddr = lrw_st->devaddr;
+		netif_receive_skb(skb);
+
+		ss->rx_skb = NULL;
+	}
+
+	mutex_lock(&lrw_st->ss_list_lock);
+	lrw_st->fcnt_down = ss->rx_fhdr.fcnt;
+	lrw_st->_cur_ss = NULL;
+	lrw_del_ss(ss);
+	lrw_st->state = LRW_STATE_IDLE;
+	mutex_unlock(&lrw_st->ss_list_lock);
+
+	return;
+
+lrw_rx_work_not_new_frame:
+	/* Drop the RX frame if checked failed */
+	kfree_skb(skb);
+}
+
+int
+lrw_check_mic(struct crypto_shash *tfm, struct sk_buff *skb)
+{
+	u32 devaddr;
+	size_t len;
+	u8 cks[4];
+	u16 fcnt;
+	u8 *buf;
+	u8 *mic;
+
+	buf = skb->data;
+	devaddr = le32_to_cpu(*((__le32 *)(buf + LRW_MHDR_LEN)));
+	fcnt = le16_to_cpu(*(__le16 *)(buf + 6));
+	len = skb->len - 4;
+	mic = skb->data + len;
+
+	lrw_calc_mic(tfm, LRW_DOWNLINK, devaddr, fcnt, buf, len, cks);
+
+	return (!memcmp(cks, mic, 4));
+}
+
+/**
+ * lrw_rx_irqsave - Tell LoRaWAN module that there is new received frame
+ * @hw:		the LoRa device
+ * @skb:	the new received frame
+ */
+void
+lrw_rx_irqsave(struct lrw_hw *hw, struct sk_buff *skb)
+{
+	struct lrw_struct *lrw_st = container_of(hw, struct lrw_struct, hw);
+	u32 devaddr;
+	u8 mtype;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	mtype = skb->data[0] >> 5;
+	devaddr = le32_to_cpu(*(__le32 *)(skb->data + LRW_MHDR_LEN));
+
+	/* Check the frame is the downlink frame */
+	if ((mtype == LRW_UNCONFIRMED_DATA_DOWN ||
+	     mtype == LRW_CONFIRMED_DATA_DOWN) &&
+	     devaddr == lrw_st->devaddr &&
+	     lrw_check_mic(lrw_st->nwks_shash_tfm, skb)) {
+		skb_queue_tail(&lrw_st->rx_skb_list, skb);
+		schedule_work(&lrw_st->rx_work);
+	} else {
+		kfree_skb(skb);
+	}
+}
+EXPORT_SYMBOL(lrw_rx_irqsave);
+
+static void
+lrw_rexmit(struct timer_list *timer)
+{
+	struct lrw_session *ss = container_of(timer, struct lrw_session, timer);
+	struct lrw_struct *lrw_st = ss->lrw_st;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	lrw_st->state = LRW_STATE_TX;
+	lrw_xmit((unsigned long)lrw_st);
+}
+
+static void
+rx_timeout_work(struct work_struct *work)
+{
+	struct lrw_struct *lrw_st;
+	struct lrw_session *ss;
+
+	ss = container_of(work, struct lrw_session, timeout_work);
+	lrw_st = ss->lrw_st;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+	mutex_lock(&lrw_st->ss_list_lock);
+	lrw_st->_cur_ss = NULL;
+	lrw_st->state = LRW_STATE_IDLE;
+	lrw_del_ss(ss);
+	mutex_unlock(&lrw_st->ss_list_lock);
+}
+
+static void
+rx2_timeout_isr(struct timer_list *timer)
+{
+	struct lrw_session *ss = container_of(timer, struct lrw_session, timer);
+	struct lrw_struct *lrw_st = ss->lrw_st;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	/* Check TX is acked or not */
+	if (!ss->tx_should_ack) {
+		spin_lock_bh(&ss->state_lock);
+		if (ss->state != LRW_RXRECEIVED_SS)
+			ss->state = LRW_RXTIMEOUT_SS;
+		spin_unlock_bh(&ss->state_lock);
+
+		if (ss->state == LRW_RXTIMEOUT_SS) {
+			netdev_dbg(lrw_st->ndev, "%s: rx time out\n", __func__);
+			goto rx2_timeout_isr_no_retry_rx_frame;
+		} else {
+			return;
+		}
+	}
+
+	/* Check the session need to be retransmitted or not */
+	if (ss->retry > 0) {
+		ss->state = LRW_RETRANSMIT_SS;
+		ss->retry--;
+
+		/* Start timer for ack timeout and retransmit */
+		ss->timer.function = lrw_rexmit;
+		ss->timer.expires = jiffies_64 + ss->ack_timeout * HZ;
+		add_timer(&ss->timer);
+	} else {
+		/* Retry failed */
+rx2_timeout_isr_no_retry_rx_frame:
+		schedule_work(&ss->timeout_work);
+	}
+}
+
+static void
+rx2_delay_isr(struct timer_list *timer)
+{
+	struct lrw_session *ss = container_of(timer, struct lrw_session, timer);
+	struct lrw_struct *lrw_st = ss->lrw_st;
+	unsigned long delay;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	/* Start timer for RX2 window */
+	ss->timer.function = rx2_timeout_isr;
+	delay = jiffies_64 + (ss->rx2_window + 20) * HZ / 1000 + HZ;
+	ss->timer.expires = delay;
+	add_timer(&ss->timer);
+
+	/* Start LoRa hardware to RX2 window */
+	ss->state = LRW_RX2_SS;
+	lrw_st->ops->start_rx_window(&lrw_st->hw, ss->rx2_window + 20);
+}
+
+static void
+rx1_delay_isr(struct timer_list *timer)
+{
+	struct lrw_session *ss = container_of(timer, struct lrw_session, timer);
+	struct lrw_struct *lrw_st = ss->lrw_st;
+	unsigned long delay;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	/* Start timer for RX_Delay2 - RX_Delay2 */
+	ss->timer.function = rx2_delay_isr;
+	delay = jiffies_64 + (ss->rx_delay2 - ss->rx_delay1) * HZ;
+	ss->timer.expires = delay;
+	add_timer(&ss->timer);
+
+	/* Start LoRa hardware to RX1 window */
+	ss->state = LRW_RX1_SS;
+	lrw_st->ops->start_rx_window(&lrw_st->hw, ss->rx1_window + 20);
+}
+
+void
+lrw_sent_tx_work(struct lrw_struct *lrw_st, struct sk_buff *skb)
+{
+	struct lrw_session *ss = lrw_st->_cur_ss;
+	struct net_device *ndev;
+	unsigned long delay;
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	ss->state = LRW_XMITTED;
+
+	/* Start session timer for RX_Delay1 */
+	timer_setup(&ss->timer, rx1_delay_isr, 0);
+	delay = jiffies_64 + ss->rx_delay1 * HZ - 20 * HZ / 1000;
+	ss->timer.expires = delay;
+	add_timer(&ss->timer);
+
+	ndev = skb->dev;
+	ndev->stats.tx_packets++;
+	ndev->stats.tx_bytes += skb->len;
+	dev_consume_skb_any(skb);
+	ss->tx_skb = NULL;
+}
+
+/**
+ * lrw_xmit_complete - Tell LoRaWAN module that the frame is xmitted completely
+ * @hw:		the LoRa device
+ * @skb:	the xmitted frame
+ */
+void
+lrw_xmit_complete(struct lrw_hw *hw, struct sk_buff *skb)
+{
+	struct lrw_struct *lrw_st = container_of(hw, struct lrw_struct, hw);
+
+	netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+	lrw_sent_tx_work(lrw_st, skb);
+	lrw_st->state = LRW_STATE_RX;
+}
+EXPORT_SYMBOL(lrw_xmit_complete);
diff --git a/net/maclorawan/main.c b/net/maclorawan/main.c
new file mode 100644
index 000000000000..49beed5111b8
--- /dev/null
+++ b/net/maclorawan/main.c
@@ -0,0 +1,605 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause
+/*-
+ * LoRaWAN soft MAC
+ *
+ * Copyright (c) 2018 Jian-Hong, Pan <starnight@g.ncu.edu.tw>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+
+#include <linux/lora/lorawan.h>
+#include <linux/lora/lorawan_netdev.h>
+#include "maclorawan.h"
+
+#define	PHY_NAME		"lora"
+
+/* Need to find a way to define or assign */
+#define	LORAWAN_MTU		20
+
+static struct class *lrw_sys_class;
+
+static void
+lrw_if_setup(struct net_device *ndev)
+{
+	ndev->addr_len = LRW_DEVADDR_LEN;
+	memset(ndev->broadcast, 0xFF, ndev->addr_len);
+	ndev->type = ARPHRD_LORAWAN;
+
+	ndev->hard_header_len = LRW_MHDR_LEN + LRW_FHDR_MAX_LEN + LRW_FPORT_LEN;
+	ndev->needed_tailroom = LRW_MIC_LEN;
+
+	/**
+	 * TODO: M should be a dynamic value defined by Regional Parameters,
+	 *	 Being fixed for now.  Going to be changed.
+	 */
+	ndev->mtu = LORAWAN_MTU;
+}
+
+/**
+ * lrw_alloc_hw - Allocate a memory space for the LoRa device
+ * @priv_data_len:	the private data size
+ * @lrw_operations:	the implemented operations of the LoRa device
+ *
+ * Return:		address of the LoRa device or NULL for failed
+ */
+struct lrw_hw *
+lrw_alloc_hw(size_t priv_data_len, struct lrw_operations *ops)
+{
+	struct lrw_struct *lrw_st;
+	struct net_device *ndev;
+	int ret;
+
+	if (WARN_ON(!ops || !ops->start || !ops->stop || !ops->xmit_async ||
+		    !ops->set_txpower || !ops->set_dr ||
+		    !ops->start_rx_window || !ops->set_state))
+		return NULL;
+
+	/* In memory it'll be like this:
+	 *
+	 * +-----------------------+
+	 * | struct net_device     |
+	 * +-----------------------+
+	 * | struct lrw_struct     |
+	 * +-----------------------+
+	 * | driver's private data |
+	 * +-----------------------+
+	 */
+	ndev = alloc_netdev(sizeof(struct lrw_struct) + priv_data_len,
+			    PHY_NAME "%d", NET_NAME_ENUM, lrw_if_setup);
+	if (!ndev)
+		return ERR_PTR(-ENOMEM);
+	ret = dev_alloc_name(ndev, ndev->name);
+	if (ret < 0)
+		goto lrw_alloc_hw_err;
+
+	lrw_st = (struct lrw_struct *)netdev_priv(ndev);
+	lrw_st->ndev = ndev;
+
+	lrw_st->state = LRW_STOP;
+	lrw_st->ops = ops;
+	lrw_st->hw.priv = (u8 *)lrw_st + sizeof(struct lrw_struct);
+
+	ndev->flags |= IFF_NOARP;
+	ndev->features |= NETIF_F_HW_CSUM;
+
+	return &lrw_st->hw;
+
+lrw_alloc_hw_err:
+	free_netdev(ndev);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(lrw_alloc_hw);
+
+/**
+ * lrw_free_hw - Free the LoRa device's memory resource
+ * @hw:		the LoRa device going to be freed
+ */
+void
+lrw_free_hw(struct lrw_hw *hw)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	free_netdev(lrw_st->ndev);
+}
+EXPORT_SYMBOL(lrw_free_hw);
+
+/**
+ * lrw_set_deveui - Set the LoRa device's DevEUI
+ * @hw:		the LoRa device going to be set
+ * @eui:	the global end-device ID in IEEE EUI64 address space
+ */
+void
+lrw_set_deveui(struct lrw_hw *hw, u64 eui)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	lrw_st->dev_eui = eui;
+}
+EXPORT_SYMBOL(lrw_set_deveui);
+
+/**
+ * lrw_get_deveui - Get the LoRa device's DevEUI
+ * @hw:		the LoRa device going to be got from
+ *
+ * Return:	the device's DevEUI in IEEE EUI64 address space
+ */
+u64
+lrw_get_deveui(struct lrw_hw *hw)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	return lrw_st->dev_eui;
+}
+EXPORT_SYMBOL(lrw_get_deveui);
+
+/**
+ * lrw_set_appeui - Set the LoRa device's AppEUI
+ * @hw:		the LoRa device going to be set
+ * @eui:	the global end-device ID in IEEE EUI64 address space
+ */
+void
+lrw_set_appeui(struct lrw_hw *hw, u64 eui)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	lrw_st->app_eui = eui;
+}
+EXPORT_SYMBOL(lrw_set_appeui);
+
+/**
+ * lrw_get_appeui - Get the LoRa device's AppEUI
+ * @hw:		the LoRa device going to be got from
+ *
+ * Return:	the device's AppEUI in IEEE EUI64 address space
+ */
+u64
+lrw_get_appeui(struct lrw_hw *hw)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	return lrw_st->app_eui;
+}
+EXPORT_SYMBOL(lrw_get_appeui);
+
+/**
+ * lrw_set_devaddr - Set the LoRa device's address
+ * @hw:		the LoRa device going to be set
+ * @devaddr:	the device address
+ */
+void
+lrw_set_devaddr(struct lrw_hw *hw, u32 devaddr)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	lrw_st->devaddr = devaddr;
+}
+EXPORT_SYMBOL(lrw_set_devaddr);
+
+/**
+ * lrw_get_devaddr - Get the LoRa device's address
+ * @hw:		the LoRa device going to be got from
+ *
+ * Return:	the device address
+ */
+u32
+lrw_get_devaddr(struct lrw_hw *hw)
+{
+	struct lrw_struct *lrw_st;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+	return lrw_st->devaddr;
+}
+EXPORT_SYMBOL(lrw_get_devaddr);
+
+/**
+ * lrw_add_hw - Add a LoRaWAN hardware as a network device
+ * @lrw_st:	the LoRa device going to be added
+ *
+ * Return:	0 / other number for success / failed
+ */
+static int
+lrw_add_hw(struct lrw_struct *lrw_st)
+{
+	struct net_device *ndev = lrw_st->ndev;
+	__be32 be_addr;
+	int ret;
+
+	lrw_st->fcnt_up = 0;
+	lrw_st->fcnt_down = 0;
+	lrw_st->_cur_ss = NULL;
+
+	mutex_init(&lrw_st->ss_list_lock);
+	INIT_LIST_HEAD(&lrw_st->ss_list);
+
+	tasklet_init(&lrw_st->xmit_task, lrw_xmit, (unsigned long)lrw_st);
+	INIT_WORK(&lrw_st->rx_work, lrw_rx_work);
+
+	be_addr = cpu_to_be32(lrw_st->devaddr);
+	memcpy(ndev->perm_addr, &be_addr, ndev->addr_len);
+	memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
+
+	write_pnet(&lrw_st->_net, &init_net);
+	ret = register_netdev(ndev);
+
+	return ret;
+}
+
+/**
+ * lrw_remove_hw - Remove a LoRaWAN hardware from a network device
+ * @lrw_st:	the LoRa device going to be removed
+ */
+static void
+lrw_remove_hw(struct lrw_struct *lrw_st)
+{
+	unregister_netdev(lrw_st->ndev);
+	tasklet_kill(&lrw_st->xmit_task);
+}
+
+bool
+ready2write(struct lrw_struct *lrw_st)
+{
+	bool status = false;
+
+	if (!lrw_st->_cur_ss && lrw_st->state == LRW_STATE_IDLE)
+		status = true;
+
+	return status;
+}
+
+bool
+ready2read(struct lrw_struct *lrw_st)
+{
+	struct lrw_session *ss;
+	bool status = false;
+
+	if (!list_empty(&lrw_st->ss_list) && lrw_st->state != LRW_STOP) {
+		ss = list_first_entry(&lrw_st->ss_list,
+				      struct lrw_session,
+				      entry);
+		if (ss->state == LRW_RXRECEIVED_SS)
+			status = true;
+	}
+
+	return status;
+}
+
+static int
+lrw_if_up(struct net_device *ndev)
+{
+	struct lrw_struct *lrw_st = NETDEV_2_LRW(ndev);
+	int ret = -EBUSY;
+
+	if (lrw_st->state == LRW_STOP) {
+		ret = lrw_start_hw(lrw_st);
+		netif_start_queue(ndev);
+	}
+
+	return ret;
+}
+
+static int
+lrw_if_down(struct net_device *ndev)
+{
+	struct lrw_struct *lrw_st = NETDEV_2_LRW(ndev);
+
+	if (lrw_st->state != LRW_STOP) {
+		netif_stop_queue(ndev);
+		lrw_stop_hw(lrw_st);
+	}
+
+	return 0;
+}
+
+static netdev_tx_t
+lrw_if_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+	struct lrw_struct *lrw_st = NETDEV_2_LRW(ndev);
+	struct lrw_session *ss;
+	netdev_tx_t ret;
+
+	ret = NETDEV_TX_OK;
+
+	ss = lrw_alloc_ss(lrw_st);
+	if (!ss)
+		return NETDEV_TX_BUSY;
+
+	mutex_lock(&lrw_st->ss_list_lock);
+	if (ready2write(lrw_st)) {
+		list_add_tail(&ss->entry, &lrw_st->ss_list);
+		lrw_st->state = LRW_STATE_TX;
+		lrw_st->_cur_ss = ss;
+		ss->fcnt_up = lrw_st->fcnt_up;
+		ss->fcnt_down = lrw_st->fcnt_down;
+		/* TODO: RX delay #1/#2 should be set by regional parameters */
+		ss->rx_delay1 = 1;
+		ss->rx_delay2 = 2;
+		ss->rx1_window = 500;
+		ss->rx2_window = 500;
+	} else {
+		ret = NETDEV_TX_BUSY;
+	}
+	mutex_unlock(&lrw_st->ss_list_lock);
+
+	if (ret == NETDEV_TX_OK) {
+		ss->state = LRW_INIT_SS;
+		ss->tx_skb = skb;
+		lrw_prepare_tx_frame(ss);
+		tasklet_schedule(&lrw_st->xmit_task);
+	} else {
+		lrw_free_ss(ss);
+	}
+
+	return ret;
+}
+
+static int
+lrw_if_get_addr(struct lrw_struct *lrw_st, struct sockaddr_lorawan *addr)
+{
+	int ret = 0;
+
+	switch (addr->addr_in.addr_type) {
+	case LRW_ADDR_DEVADDR:
+		addr->addr_in.devaddr = lrw_st->devaddr;
+		break;
+	case LRW_ADDR_DEVEUI:
+		addr->addr_in.dev_eui = lrw_st->dev_eui;
+		break;
+	case LRW_ADDR_APPEUI:
+		addr->addr_in.app_eui = lrw_st->app_eui;
+		break;
+	default:
+		ret = -ENOTSUPP;
+	}
+
+	return ret;
+}
+
+static int
+lrw_if_set_addr(struct lrw_struct *lrw_st, struct sockaddr_lorawan *addr)
+{
+	struct lrw_hw *hw = &lrw_st->hw;
+	int ret = 0;
+
+	if (netif_running(lrw_st->ndev))
+		return -EBUSY;
+
+	switch (addr->addr_in.addr_type) {
+	case LRW_ADDR_DEVADDR:
+		lrw_set_devaddr(hw, addr->addr_in.devaddr);
+		break;
+	case LRW_ADDR_DEVEUI:
+		lrw_set_deveui(hw, addr->addr_in.dev_eui);
+		break;
+	case LRW_ADDR_APPEUI:
+		lrw_set_appeui(hw, addr->addr_in.app_eui);
+		break;
+	default:
+		ret = -ENOTSUPP;
+	}
+
+	return ret;
+}
+
+static void
+swap_bytes(u8 *dst, u8 *src, size_t l)
+{
+	/* Human reading is big-endian, but LoRaWAN is little-endian */
+	unsigned int i;
+
+	for (i = 0; i < l; i++)
+		dst[i] = src[l - i - 1];
+}
+
+int
+lrw_set_key(struct lrw_hw *hw, u8 type, u8 *key, size_t key_len)
+{
+	struct lrw_struct *lrw_st;
+	int ret = 0;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+
+	netdev_dbg(lrw_st->ndev, "%s: type=%d\n", __func__, type);
+	if (lrw_st->state != LRW_STOP)
+		return -EINVAL;
+
+	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
+		       16, 1, key, key_len, true);
+	switch (type) {
+	case LRW_APPKEY:
+		swap_bytes(lrw_st->appkey, key, key_len);
+		break;
+	case LRW_NWKSKEY:
+		swap_bytes(lrw_st->nwkskey, key, key_len);
+		break;
+	case LRW_APPSKEY:
+		swap_bytes(lrw_st->appskey, key, key_len);
+		break;
+	default:
+		ret = -ENOTSUPP;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(lrw_set_key);
+
+int
+lrw_get_key(struct lrw_hw *hw, u8 type, u8 *key, size_t key_len)
+{
+	struct lrw_struct *lrw_st;
+	int ret = 0;
+
+	lrw_st = container_of(hw, struct lrw_struct, hw);
+
+	netdev_dbg(lrw_st->ndev, "%s: type=%d\n", __func__, type);
+	switch (type) {
+	case LRW_APPKEY:
+		swap_bytes(key, lrw_st->appkey, key_len);
+		break;
+	case LRW_NWKSKEY:
+		swap_bytes(key, lrw_st->nwkskey, key_len);
+		break;
+	case LRW_APPSKEY:
+		swap_bytes(key, lrw_st->appskey, key_len);
+		break;
+	default:
+		ret = -ENOTSUPP;
+	}
+
+	return ret;
+}
+
+static int
+lrw_if_ioctl(struct net_device *ndev, struct ifreq *ifr, int cmd)
+{
+	struct lrw_struct *lrw_st = NETDEV_2_LRW(ndev);
+	struct sockaddr_lorawan *addr;
+	int ret = 0;
+
+	netdev_dbg(ndev, "%s: ioctl file (cmd=0x%X)\n", __func__, cmd);
+
+	/* I/O control by each command */
+	switch (cmd) {
+	/* Set & get the DevAddr, DevEUI and AppEUI */
+	case SIOCSIFADDR:
+		addr = (struct sockaddr_lorawan *)&ifr->ifr_addr;
+		ret = lrw_if_set_addr(lrw_st, addr);
+		break;
+	case SIOCGIFADDR:
+		addr = (struct sockaddr_lorawan *)&ifr->ifr_addr;
+		ret = lrw_if_get_addr(lrw_st, addr);
+		break;
+	default:
+		ret = -ENOTSUPP;
+	}
+
+	return ret;
+}
+
+static int
+lrw_if_set_mac(struct net_device *ndev, void *p)
+{
+	struct lrw_struct *lrw_st = NETDEV_2_LRW(ndev);
+	struct sockaddr *addr = p;
+	__be32 *be_addr;
+
+	be_addr = (__be32 *)addr->sa_data;
+
+	netdev_dbg(ndev, "%s: AF_TYPE:%d set mac address %X\n",
+		   __func__, addr->sa_family, be32_to_cpu(*be_addr));
+
+	if (netif_running(ndev))
+		return -EBUSY;
+
+	lrw_set_devaddr(&lrw_st->hw, be32_to_cpu(*be_addr));
+	memcpy(ndev->dev_addr, be_addr, ndev->addr_len);
+
+	return 0;
+}
+
+static const struct net_device_ops lrw_if_ops = {
+	.ndo_open = lrw_if_up,
+	.ndo_stop = lrw_if_down,
+	.ndo_start_xmit = lrw_if_start_xmit,
+	.ndo_do_ioctl = lrw_if_ioctl,
+	.ndo_set_mac_address = lrw_if_set_mac,
+};
+
+/**
+ * lrw_register_hw - Register as a LoRaWAN compatible device
+ * @hw:		LoRa device going to be registered
+ *
+ * Return:	0 / negative number for success / error number
+ */
+int
+lrw_register_hw(struct lrw_hw *hw)
+{
+	struct lrw_struct *lrw_st = container_of(hw, struct lrw_struct, hw);
+	int ret;
+
+	device_initialize(&lrw_st->dev);
+	dev_set_name(&lrw_st->dev, netdev_name(lrw_st->ndev));
+	lrw_st->dev.class = lrw_sys_class;
+	lrw_st->dev.platform_data = lrw_st;
+
+	ret = device_add(&lrw_st->dev);
+	if (ret)
+		goto lrw_register_hw_end;
+
+	/* Add a LoRa device node as a network device */
+	lrw_st->ndev->netdev_ops = &lrw_if_ops;
+	ret = lrw_add_hw(lrw_st);
+	if (!ret)
+		netdev_info(lrw_st->ndev, "register\n");
+
+lrw_register_hw_end:
+	return ret;
+}
+EXPORT_SYMBOL(lrw_register_hw);
+
+/**
+ * lrw_unregister_hw - Unregister the LoRaWAN compatible device
+ * @hw:		LoRa device going to be unregistered
+ */
+void
+lrw_unregister_hw(struct lrw_hw *hw)
+{
+	struct lrw_struct *lrw_st = container_of(hw, struct lrw_struct, hw);
+
+	netdev_info(lrw_st->ndev, "unregister\n");
+
+	/* Stop and remove the LoRaWAM hardware from system */
+	if (lrw_st->state != LRW_STOP)
+		lrw_stop_hw(lrw_st);
+	device_del(&lrw_st->dev);
+	lrw_remove_hw(lrw_st);
+}
+EXPORT_SYMBOL(lrw_unregister_hw);
+
+static int __init
+lrw_init(void)
+{
+	int err = 0;
+
+	pr_info("%s: module inserted\n", LORAWAN_MODULE_NAME);
+
+	/* Create device class */
+	lrw_sys_class = class_create(THIS_MODULE, LORAWAN_MODULE_NAME);
+	if (IS_ERR(lrw_sys_class)) {
+		pr_err("%s: Failed to create a class of LoRaWAN\n",
+		       LORAWAN_MODULE_NAME);
+		err = PTR_ERR(lrw_sys_class);
+		goto lrw_init_end;
+	}
+
+	pr_debug("%s: class created\n", LORAWAN_MODULE_NAME);
+
+lrw_init_end:
+	return err;
+}
+
+static void __exit
+lrw_exit(void)
+{
+	/* Delete device class */
+	class_destroy(lrw_sys_class);
+	pr_info("%s: module removed\n", LORAWAN_MODULE_NAME);
+}
+
+module_init(lrw_init);
+module_exit(lrw_exit);
+
+MODULE_AUTHOR("Jian-Hong Pan, <starnight@g.ncu.edu.tw>");
+MODULE_DESCRIPTION("LoRaWAN soft MAC kernel module");
+MODULE_LICENSE("Dual BSD/GPL");