[linux.git] / net / mac802154 / rx.c

/*
 * Copyright (C) 2007-2012 Siemens AG
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Written by:
 * Pavel Smolenskiy <[email protected]>
 * Maxim Gorbachyov <[email protected]>
 * Dmitry Eremin-Solenikov <[email protected]>
 * Alexander Smirnov <[email protected]>
 */

#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 (mac_cb(skb)->dest.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_init(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);

	mac_cb(skb)->lqi = lqi;
	skb->pkt_type = IEEE802154_RX_MSG;
	skb_queue_tail(&local->skb_queue, skb);
	tasklet_schedule(&local->tasklet);
}
EXPORT_SYMBOL(ieee802154_rx_irqsafe);
Commit	Line	Data
1cd829c8	1	/*
	2	* Copyright (C) 2007-2012 Siemens AG
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2
	6	* as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
1cd829c8	13	* Written by:
	14	* Pavel Smolenskiy <[email protected]>
	15	* Maxim Gorbachyov <[email protected]>
	16	* Dmitry Eremin-Solenikov <[email protected]>
	17	* Alexander Smirnov <[email protected]>
	18	*/
	19
	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
1cd829c8	22	#include <linux/netdevice.h>
1cd829c8	23	#include <linux/crc-ccitt.h>
b7889497	24	#include <asm/unaligned.h>
1cd829c8	25
	26	#include <net/mac802154.h>
	27	#include <net/ieee802154_netdev.h>
944742a3	28	#include <net/nl802154.h>
1cd829c8	29
0f1556bc	30	#include "ieee802154_i.h"
1cd829c8	31
08c511a7	32	static int ieee802154_deliver_skb(struct sk_buff *skb)
2a9820c9	33	{
75a46f0e	34	skb->ip_summed = CHECKSUM_UNNECESSARY;
702dcf99 AA	35	skb->protocol = htons(ETH_P_IEEE802154);
702dcf99 AA	36
2a9820c9 AA	37	return netif_receive_skb(skb);
	38	}
	39
	40	static int
be9d215f AA	41	ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
be9d215f AA	42	struct sk_buff skb, const struct ieee802154_hdr hdr)
2a9820c9	43	{
863e88f2	44	struct wpan_dev *wpan_dev = &sdata->wpan_dev;
2a9820c9 AA	45	__le16 span, sshort;
	46	int rc;
	47
	48	pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
	49
863e88f2 AA	50	span = wpan_dev->pan_id;
863e88f2 AA	51	sshort = wpan_dev->short_addr;
2a9820c9 AA	52
	53	switch (mac_cb(skb)->dest.mode) {
	54	case IEEE802154_ADDR_NONE:
	55	if (mac_cb(skb)->dest.mode != IEEE802154_ADDR_NONE)
	56	/* FIXME: check if we are PAN coordinator */
	57	skb->pkt_type = PACKET_OTHERHOST;
	58	else
	59	/* ACK comes with both addresses empty */
	60	skb->pkt_type = PACKET_HOST;
	61	break;
	62	case IEEE802154_ADDR_LONG:
	63	if (mac_cb(skb)->dest.pan_id != span &&
	64	mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
	65	skb->pkt_type = PACKET_OTHERHOST;
863e88f2	66	else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr)
2a9820c9 AA	67	skb->pkt_type = PACKET_HOST;
	68	else
	69	skb->pkt_type = PACKET_OTHERHOST;
	70	break;
	71	case IEEE802154_ADDR_SHORT:
	72	if (mac_cb(skb)->dest.pan_id != span &&
	73	mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
	74	skb->pkt_type = PACKET_OTHERHOST;
	75	else if (mac_cb(skb)->dest.short_addr == sshort)
	76	skb->pkt_type = PACKET_HOST;
	77	else if (mac_cb(skb)->dest.short_addr ==
	78	cpu_to_le16(IEEE802154_ADDR_BROADCAST))
	79	skb->pkt_type = PACKET_BROADCAST;
	80	else
	81	skb->pkt_type = PACKET_OTHERHOST;
	82	break;
	83	default:
2a9820c9	84	pr_debug("invalid dest mode\n");
bcb47aab	85	goto fail;
2a9820c9 AA	86	}
2a9820c9 AA	87
2a9820c9 AA	88	skb->dev = sdata->dev;
2a9820c9 AA	89
d58a2fa9 AA	90	/* TODO this should be moved after netif_receive_skb call, otherwise
	91	* wireshark will show a mac header with security fields and the
	92	* payload is already decrypted.
	93	*/
2a9820c9 AA	94	rc = mac802154_llsec_decrypt(&sdata->sec, skb);
	95	if (rc) {
	96	pr_debug("decryption failed: %i\n", rc);
	97	goto fail;
	98	}
	99
	100	sdata->dev->stats.rx_packets++;
	101	sdata->dev->stats.rx_bytes += skb->len;
	102
	103	switch (mac_cb(skb)->type) {
ca1de81a AR	104	case IEEE802154_FC_TYPE_BEACON:
	105	case IEEE802154_FC_TYPE_ACK:
	106	case IEEE802154_FC_TYPE_MAC_CMD:
	107	goto fail;
	108
2a9820c9	109	case IEEE802154_FC_TYPE_DATA:
08c511a7	110	return ieee802154_deliver_skb(skb);
2a9820c9	111	default:
bd89bb6d AR	112	pr_warn_ratelimited("ieee802154: bad frame received "
bd89bb6d AR	113	"(type = %d)\n", mac_cb(skb)->type);
2a9820c9 AA	114	goto fail;
	115	}
	116
	117	fail:
	118	kfree_skb(skb);
	119	return NET_RX_DROP;
	120	}
	121
be9d215f AA	122	static void
be9d215f AA	123	ieee802154_print_addr(const char name, const struct ieee802154_addr addr)
2a9820c9 AA	124	{
	125	if (addr->mode == IEEE802154_ADDR_NONE)
	126	pr_debug("%s not present\n", name);
	127
	128	pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id));
	129	if (addr->mode == IEEE802154_ADDR_SHORT) {
	130	pr_debug("%s is short: %04x\n", name,
	131	le16_to_cpu(addr->short_addr));
	132	} else {
	133	u64 hw = swab64((__force u64)addr->extended_addr);
	134
	135	pr_debug("%s is hardware: %8phC\n", name, &hw);
	136	}
	137	}
	138
be9d215f AA	139	static int
be9d215f AA	140	ieee802154_parse_frame_start(struct sk_buff skb, struct ieee802154_hdr hdr)
2a9820c9 AA	141	{
	142	int hlen;
	143	struct ieee802154_mac_cb *cb = mac_cb_init(skb);
	144
9cf215d0 AA	145	skb_reset_mac_header(skb);
9cf215d0 AA	146
2a9820c9 AA	147	hlen = ieee802154_hdr_pull(skb, hdr);
	148	if (hlen < 0)
	149	return -EINVAL;
	150
	151	skb->mac_len = hlen;
	152
	153	pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc),
	154	hdr->seq);
	155
	156	cb->type = hdr->fc.type;
	157	cb->ackreq = hdr->fc.ack_request;
	158	cb->secen = hdr->fc.security_enabled;
	159
be9d215f AA	160	ieee802154_print_addr("destination", &hdr->dest);
be9d215f AA	161	ieee802154_print_addr("source", &hdr->source);
2a9820c9 AA	162
	163	cb->source = hdr->source;
	164	cb->dest = hdr->dest;
	165
	166	if (hdr->fc.security_enabled) {
	167	u64 key;
	168
	169	pr_debug("seclevel %i\n", hdr->sec.level);
	170
	171	switch (hdr->sec.key_id_mode) {
	172	case IEEE802154_SCF_KEY_IMPLICIT:
	173	pr_debug("implicit key\n");
	174	break;
	175
	176	case IEEE802154_SCF_KEY_INDEX:
	177	pr_debug("key %02x\n", hdr->sec.key_id);
	178	break;
	179
	180	case IEEE802154_SCF_KEY_SHORT_INDEX:
	181	pr_debug("key %04x:%04x %02x\n",
	182	le32_to_cpu(hdr->sec.short_src) >> 16,
	183	le32_to_cpu(hdr->sec.short_src) & 0xffff,
	184	hdr->sec.key_id);
	185	break;
	186
	187	case IEEE802154_SCF_KEY_HW_INDEX:
	188	key = swab64((__force u64)hdr->sec.extended_src);
	189	pr_debug("key source %8phC %02x\n", &key,
	190	hdr->sec.key_id);
	191	break;
	192	}
	193	}
	194
	195	return 0;
	196	}
	197
	198	static void
be9d215f AA	199	__ieee802154_rx_handle_packet(struct ieee802154_local *local,
be9d215f AA	200	struct sk_buff *skb)
2a9820c9 AA	201	{
	202	int ret;
	203	struct ieee802154_sub_if_data *sdata;
	204	struct ieee802154_hdr hdr;
	205
be9d215f	206	ret = ieee802154_parse_frame_start(skb, &hdr);
2a9820c9 AA	207	if (ret) {
	208	pr_debug("got invalid frame\n");
	209	kfree_skb(skb);
	210	return;
	211	}
	212
2a9820c9	213	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1bc1754e VB	214	if (sdata->wpan_dev.iftype != NL802154_IFTYPE_NODE)
	215	continue;
	216
	217	if (!ieee802154_sdata_running(sdata))
2a9820c9 AA	218	continue;
2a9820c9 AA	219
be9d215f	220	ieee802154_subif_frame(sdata, skb, &hdr);
2a9820c9 AA	221	skb = NULL;
	222	break;
	223	}
2a9820c9	224
56f9ebe6	225	kfree_skb(skb);
2a9820c9 AA	226	}
2a9820c9 AA	227
4ca18be5	228	static void
be9d215f	229	ieee802154_monitors_rx(struct ieee802154_local local, struct sk_buff skb)
2a9820c9 AA	230	{
	231	struct sk_buff *skb2;
	232	struct ieee802154_sub_if_data *sdata;
2a9820c9	233
9cf215d0	234	skb_reset_mac_header(skb);
75a46f0e	235	skb->ip_summed = CHECKSUM_UNNECESSARY;
c9ca6401	236	skb->pkt_type = PACKET_OTHERHOST;
702dcf99 AA	237	skb->protocol = htons(ETH_P_IEEE802154);
702dcf99 AA	238
2a9820c9	239	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
ed65963b	240	if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR)
20b48120 AA	241	continue;
	242
	243	if (!ieee802154_sdata_running(sdata))
2a9820c9 AA	244	continue;
	245
	246	skb2 = skb_clone(skb, GFP_ATOMIC);
05f7de67 AA	247	if (skb2) {
	248	skb2->dev = sdata->dev;
	249	ieee802154_deliver_skb(skb2);
2a9820c9	250
05f7de67 AA	251	sdata->dev->stats.rx_packets++;
	252	sdata->dev->stats.rx_bytes += skb->len;
	253	}
2a9820c9	254	}
2a9820c9 AA	255	}
2a9820c9 AA	256
d10270ce	257	void ieee802154_rx(struct ieee802154_local local, struct sk_buff skb)
1cd829c8	258	{
ec718f3d	259	u16 crc;
1cd829c8	260
469100d6 AA	261	WARN_ON_ONCE(softirq_count() == 0);
469100d6 AA	262
3cf24cf8 AA	263	if (local->suspended)
	264	goto drop;
	265
b7889497 AA	266	/* TODO: When a transceiver omits the checksum here, we
	267	* add an own calculated one. This is currently an ugly
	268	* solution because the monitor needs a crc here.
	269	*/
	270	if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) {
ec718f3d	271	crc = crc_ccitt(0, skb->data, skb->len);
b7889497	272	put_unaligned_le16(crc, skb_put(skb, 2));
1cd829c8	273	}
1cd829c8	274
e176b681 AA	275	rcu_read_lock();
e176b681 AA	276
be9d215f	277	ieee802154_monitors_rx(local, skb);
2d3b5b0a	278
ec718f3d AA	279	/* Check if transceiver doesn't validate the checksum.
	280	* If not we validate the checksum here.
	281	*/
	282	if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) {
	283	crc = crc_ccitt(0, skb->data, skb->len);
	284	if (crc) {
	285	rcu_read_unlock();
3cf24cf8	286	goto drop;
ec718f3d AA	287	}
ec718f3d AA	288	}
b7889497 AA	289	/* remove crc */
b7889497 AA	290	skb_trim(skb, skb->len - 2);
e176b681	291
b7889497	292	__ieee802154_rx_handle_packet(local, skb);
2d3b5b0a	293
b7889497	294	rcu_read_unlock();
3cf24cf8 AA	295
	296	return;
	297	drop:
	298	kfree_skb(skb);
1cd829c8	299	}
1cd829c8	300
1cd829c8	301	void
5a504397	302	ieee802154_rx_irqsafe(struct ieee802154_hw hw, struct sk_buff skb, u8 lqi)
1cd829c8	303	{
60741361	304	struct ieee802154_local *local = hw_to_local(hw);
1cd829c8	305
c5c47e67 AA	306	mac_cb(skb)->lqi = lqi;
	307	skb->pkt_type = IEEE802154_RX_MSG;
	308	skb_queue_tail(&local->skb_queue, skb);
	309	tasklet_schedule(&local->tasklet);
1cd829c8	310	}
1cd829c8	311	EXPORT_SYMBOL(ieee802154_rx_irqsafe);