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@xxxxxxxxxxxx>
---
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
V5:
- Initial rx_skb_list when it is allocated with LoRa hardware
- Check the sk_buff's data length before access it
- Deal FPort field and decrypt payload in lrw_parse_frame function
- Drop the recieved frame if parse failed
- Fix the bug which passes wrong skb properties from maclorawan to lorawan module
net/maclorawan/Kconfig | 14 +
net/maclorawan/Makefile | 2 +
net/maclorawan/mac.c | 555 ++++++++++++++++++++++++++++++++++++
net/maclorawan/main.c | 606 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 1177 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
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..459ab95ff52d
--- /dev/null
+++ b/net/maclorawan/mac.c
@@ -0,0 +1,555 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause
+/*-
+ * LoRaWAN soft MAC
+ *
+ * Copyright (c) 2018 Jian-Hong, Pan <starnight@xxxxxxxxxxxx>
+ *
+ */
+
+#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;
+ u8 mic[LRW_MIC_LEN];
+ __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, LRW_FCNT_LEN), &le_fcnt_up, LRW_FCNT_LEN);
+
+ /* Push FCtrl */
+ fctrl = 0;
+ if (lrw_st->rx_should_ack) {
+ fctrl |= 0x20;
+ lrw_st->rx_should_ack = false;
+ }
+ memcpy(skb_push(skb, LRW_FCTRL_LEN), &fctrl, LRW_FCTRL_LEN);
+
+ /* 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);
+}
+
+int
+lrw_parse_frame(struct lrw_session *ss, struct sk_buff *skb)
+{
+ struct lrw_struct *lrw_st = ss->lrw_st;
+ 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, LRW_DEVADDR_LEN);
+
+ /* Get frame control */
+ fhdr->fctrl = skb->data[0];
+ skb_pull(skb, LRW_FCTRL_LEN);
+
+ /* 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, LRW_FCNT_LEN);
+
+ /* Get frame options */
+ fhdr->fopts_len = fhdr->fctrl & 0xF;
+ if (fhdr->fopts_len > 0) {
+ if (skb->len < fhdr->fopts_len)
+ goto lrw_parse_frame_err;
+ memcpy(fhdr->fopts, skb->data, fhdr->fopts_len);
+ skb_pull(skb, fhdr->fopts_len);
+ }
+
+ /* TODO: Parse frame options */
+
+ /* Parse FPort and decrypt payload */
+ if (skb->len > 0) {
+ if (skb->len <= LRW_FPORT_LEN)
+ goto lrw_parse_frame_err;
+
+ /* TODO: Deal FPort */
+
+ skb_pull(skb, LRW_FPORT_LEN);
+
+ lrw_decrypt_buf(lrw_st->apps_skc_tfm, LRW_DOWNLINK,
+ ss->devaddr, fhdr->fcnt, skb->data, skb->len);
+ }
+
+ return 0;
+
+lrw_parse_frame_err:
+ return -EMSGSIZE;
+}
+
+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;
+ u16 ofs;
+
+ netdev_dbg(lrw_st->ndev, "%s\n", __func__);
+
+ ofs = LRW_MHDR_LEN + LRW_DEVADDR_LEN + LRW_FCTRL_LEN;
+ p_fcnt = (__le16 *)(rx_skb->data + ofs);
+ 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 = 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;
+
+ if (lrw_parse_frame(ss, skb)) {
+ ss->rx_skb = NULL;
+ goto lrw_rx_work_not_new_frame;
+ }
+
+ /* 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;
+
+ spin_lock_bh(&ss->state_lock);
+ ss->state = LRW_RXRECEIVED_SS;
+ spin_unlock_bh(&ss->state_lock);
+
+ if (ss->rx_skb->len > 0) {
+ lrw_get_mac_cb(skb)->devaddr = lrw_st->devaddr;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ skb->protocol = htons(ETH_P_LORAWAN);
+ skb->pkt_type = PACKET_HOST;
+ 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 */
+ if (skb)
+ kfree_skb(skb);
+}
+
+int
+lrw_check_mic(struct crypto_shash *tfm, struct sk_buff *skb)
+{
+ u8 cks[LRW_MIC_LEN];
+ u32 devaddr;
+ size_t len;
+ u16 fcnt;
+ u8 *buf;
+ u8 *mic;
+ u16 ofs;
+
+ buf = skb->data;
+ devaddr = le32_to_cpu(*((__le32 *)(buf + LRW_MHDR_LEN)));
+ ofs = LRW_MHDR_LEN + LRW_DEVADDR_LEN + LRW_FCTRL_LEN;
+ fcnt = le16_to_cpu(*(__le16 *)(buf + ofs));
+ len = skb->len - LRW_MIC_LEN;
+ mic = skb->data + len;
+
+ lrw_calc_mic(tfm, LRW_DOWNLINK, devaddr, fcnt, buf, len, cks);
+
+ return (!memcmp(cks, mic, LRW_MIC_LEN));
+}
+
+/**
+ * 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__);
+
+ if (skb->len < LRW_MHDR_LEN + LRW_DEVADDR_LEN + LRW_FCTRL_LEN +
+ LRW_FCNT_LEN + LRW_MIC_LEN)
+ goto lrw_rx_irqsave_err;
+
+ 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)) {
+ /* Remove message integrity code (MIC) */
+ skb_trim(skb, skb->len - LRW_MIC_LEN);
+ skb_queue_tail(&lrw_st->rx_skb_list, skb);
+ schedule_work(&lrw_st->rx_work);
+ return;
+ }
+
+lrw_rx_irqsave_err:
+ 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..caecfb3f66c6
--- /dev/null
+++ b/net/maclorawan/main.c
@@ -0,0 +1,606 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause
+/*-
+ * LoRaWAN soft MAC
+ *
+ * Copyright (c) 2018 Jian-Hong, Pan <starnight@xxxxxxxxxxxx>
+ *
+ */
+
+#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);
+ skb_queue_head_init(&lrw_st->rx_skb_list);
+
+ 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@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("LoRaWAN soft MAC kernel module");
+MODULE_LICENSE("Dual BSD/GPL");
--
2.20.0
