1 files changed, 304 insertions, 0 deletions
diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c
new file mode 100644
index 000000000..726b47a46
--- /dev/null
+++ b/net/mac802154/rx.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2007-2012 Siemens AG
+ *
+ * Written by:
+ * Pavel Smolenskiy <pavel.smolenskiy@gmail.com>
+ * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
+ * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
+ * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/crc-ccitt.h>
+#include <asm/unaligned.h>
+
+#include <net/mac802154.h>
+#include <net/ieee802154_netdev.h>
+#include <net/nl802154.h>
+
+#include "ieee802154_i.h"
+
+static int ieee802154_deliver_skb(struct sk_buff *skb)
+{
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	skb->protocol = htons(ETH_P_IEEE802154);
+
+	return netif_receive_skb(skb);
+}
+
+static int
+ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
+		       struct sk_buff *skb, const struct ieee802154_hdr *hdr)
+{
+	struct wpan_dev *wpan_dev = &sdata->wpan_dev;
+	__le16 span, sshort;
+	int rc;
+
+	pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
+
+	span = wpan_dev->pan_id;
+	sshort = wpan_dev->short_addr;
+
+	switch (mac_cb(skb)->dest.mode) {
+	case IEEE802154_ADDR_NONE:
+		if (hdr->source.mode != IEEE802154_ADDR_NONE)
+			/* FIXME: check if we are PAN coordinator */
+			skb->pkt_type = PACKET_OTHERHOST;
+		else
+			/* ACK comes with both addresses empty */
+			skb->pkt_type = PACKET_HOST;
+		break;
+	case IEEE802154_ADDR_LONG:
+		if (mac_cb(skb)->dest.pan_id != span &&
+		    mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
+			skb->pkt_type = PACKET_OTHERHOST;
+		else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr)
+			skb->pkt_type = PACKET_HOST;
+		else
+			skb->pkt_type = PACKET_OTHERHOST;
+		break;
+	case IEEE802154_ADDR_SHORT:
+		if (mac_cb(skb)->dest.pan_id != span &&
+		    mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
+			skb->pkt_type = PACKET_OTHERHOST;
+		else if (mac_cb(skb)->dest.short_addr == sshort)
+			skb->pkt_type = PACKET_HOST;
+		else if (mac_cb(skb)->dest.short_addr ==
+			  cpu_to_le16(IEEE802154_ADDR_BROADCAST))
+			skb->pkt_type = PACKET_BROADCAST;
+		else
+			skb->pkt_type = PACKET_OTHERHOST;
+		break;
+	default:
+		pr_debug("invalid dest mode\n");
+		goto fail;
+	}
+
+	skb->dev = sdata->dev;
+
+	/* TODO this should be moved after netif_receive_skb call, otherwise
+	 * wireshark will show a mac header with security fields and the
+	 * payload is already decrypted.
+	 */
+	rc = mac802154_llsec_decrypt(&sdata->sec, skb);
+	if (rc) {
+		pr_debug("decryption failed: %i\n", rc);
+		goto fail;
+	}
+
+	sdata->dev->stats.rx_packets++;
+	sdata->dev->stats.rx_bytes += skb->len;
+
+	switch (mac_cb(skb)->type) {
+	case IEEE802154_FC_TYPE_BEACON:
+	case IEEE802154_FC_TYPE_ACK:
+	case IEEE802154_FC_TYPE_MAC_CMD:
+		goto fail;
+
+	case IEEE802154_FC_TYPE_DATA:
+		return ieee802154_deliver_skb(skb);
+	default:
+		pr_warn_ratelimited("ieee802154: bad frame received "
+				    "(type = %d)\n", mac_cb(skb)->type);
+		goto fail;
+	}
+
+fail:
+	kfree_skb(skb);
+	return NET_RX_DROP;
+}
+
+static void
+ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr)
+{
+	if (addr->mode == IEEE802154_ADDR_NONE)
+		pr_debug("%s not present\n", name);
+
+	pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id));
+	if (addr->mode == IEEE802154_ADDR_SHORT) {
+		pr_debug("%s is short: %04x\n", name,
+			 le16_to_cpu(addr->short_addr));
+	} else {
+		u64 hw = swab64((__force u64)addr->extended_addr);
+
+		pr_debug("%s is hardware: %8phC\n", name, &hw);
+	}
+}
+
+static int
+ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr)
+{
+	int hlen;
+	struct ieee802154_mac_cb *cb = mac_cb(skb);
+
+	skb_reset_mac_header(skb);
+
+	hlen = ieee802154_hdr_pull(skb, hdr);
+	if (hlen < 0)
+		return -EINVAL;
+
+	skb->mac_len = hlen;
+
+	pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc),
+		 hdr->seq);
+
+	cb->type = hdr->fc.type;
+	cb->ackreq = hdr->fc.ack_request;
+	cb->secen = hdr->fc.security_enabled;
+
+	ieee802154_print_addr("destination", &hdr->dest);
+	ieee802154_print_addr("source", &hdr->source);
+
+	cb->source = hdr->source;
+	cb->dest = hdr->dest;
+
+	if (hdr->fc.security_enabled) {
+		u64 key;
+
+		pr_debug("seclevel %i\n", hdr->sec.level);
+
+		switch (hdr->sec.key_id_mode) {
+		case IEEE802154_SCF_KEY_IMPLICIT:
+			pr_debug("implicit key\n");
+			break;
+
+		case IEEE802154_SCF_KEY_INDEX:
+			pr_debug("key %02x\n", hdr->sec.key_id);
+			break;
+
+		case IEEE802154_SCF_KEY_SHORT_INDEX:
+			pr_debug("key %04x:%04x %02x\n",
+				 le32_to_cpu(hdr->sec.short_src) >> 16,
+				 le32_to_cpu(hdr->sec.short_src) & 0xffff,
+				 hdr->sec.key_id);
+			break;
+
+		case IEEE802154_SCF_KEY_HW_INDEX:
+			key = swab64((__force u64)hdr->sec.extended_src);
+			pr_debug("key source %8phC %02x\n", &key,
+				 hdr->sec.key_id);
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static void
+__ieee802154_rx_handle_packet(struct ieee802154_local *local,
+			      struct sk_buff *skb)
+{
+	int ret;
+	struct ieee802154_sub_if_data *sdata;
+	struct ieee802154_hdr hdr;
+
+	ret = ieee802154_parse_frame_start(skb, &hdr);
+	if (ret) {
+		pr_debug("got invalid frame\n");
+		kfree_skb(skb);
+		return;
+	}
+
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (sdata->wpan_dev.iftype != NL802154_IFTYPE_NODE)
+			continue;
+
+		if (!ieee802154_sdata_running(sdata))
+			continue;
+
+		ieee802154_subif_frame(sdata, skb, &hdr);
+		skb = NULL;
+		break;
+	}
+
+	kfree_skb(skb);
+}
+
+static void
+ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb)
+{
+	struct sk_buff *skb2;
+	struct ieee802154_sub_if_data *sdata;
+
+	skb_reset_mac_header(skb);
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	skb->pkt_type = PACKET_OTHERHOST;
+	skb->protocol = htons(ETH_P_IEEE802154);
+
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR)
+			continue;
+
+		if (!ieee802154_sdata_running(sdata))
+			continue;
+
+		skb2 = skb_clone(skb, GFP_ATOMIC);
+		if (skb2) {
+			skb2->dev = sdata->dev;
+			ieee802154_deliver_skb(skb2);
+
+			sdata->dev->stats.rx_packets++;
+			sdata->dev->stats.rx_bytes += skb->len;
+		}
+	}
+}
+
+void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb)
+{
+	u16 crc;
+
+	WARN_ON_ONCE(softirq_count() == 0);
+
+	if (local->suspended)
+		goto drop;
+
+	/* TODO: When a transceiver omits the checksum here, we
+	 * add an own calculated one. This is currently an ugly
+	 * solution because the monitor needs a crc here.
+	 */
+	if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) {
+		crc = crc_ccitt(0, skb->data, skb->len);
+		put_unaligned_le16(crc, skb_put(skb, 2));
+	}
+
+	rcu_read_lock();
+
+	ieee802154_monitors_rx(local, skb);
+
+	/* Check if transceiver doesn't validate the checksum.
+	 * If not we validate the checksum here.
+	 */
+	if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) {
+		crc = crc_ccitt(0, skb->data, skb->len);
+		if (crc) {
+			rcu_read_unlock();
+			goto drop;
+		}
+	}
+	/* remove crc */
+	skb_trim(skb, skb->len - 2);
+
+	__ieee802154_rx_handle_packet(local, skb);
+
+	rcu_read_unlock();
+
+	return;
+drop:
+	kfree_skb(skb);
+}
+
+void
+ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi)
+{
+	struct ieee802154_local *local = hw_to_local(hw);
+	struct ieee802154_mac_cb *cb = mac_cb_init(skb);
+
+	cb->lqi = lqi;
+	skb->pkt_type = IEEE802154_RX_MSG;
+	skb_queue_tail(&local->skb_queue, skb);
+	tasklet_schedule(&local->tasklet);
+}
+EXPORT_SYMBOL(ieee802154_rx_irqsafe);