[linux-2.6-block.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 <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 (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_DATA:
		return ieee802154_deliver_skb(skb);
	default:
		pr_warn("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 <pavel.smolenskiy@gmail.com>
	15	* Maxim Gorbachyov <maxim.gorbachev@siemens.com>
	16	* Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
	17	* Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
	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) {
	104	case IEEE802154_FC_TYPE_DATA:
08c511a7	105	return ieee802154_deliver_skb(skb);
2a9820c9 AA	106	default:
	107	pr_warn("ieee802154: bad frame received (type = %d)\n",
	108	mac_cb(skb)->type);
	109	goto fail;
	110	}
	111
	112	fail:
	113	kfree_skb(skb);
	114	return NET_RX_DROP;
	115	}
	116
be9d215f AA	117	static void
be9d215f AA	118	ieee802154_print_addr(const char name, const struct ieee802154_addr addr)
2a9820c9 AA	119	{
	120	if (addr->mode == IEEE802154_ADDR_NONE)
	121	pr_debug("%s not present\n", name);
	122
	123	pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id));
	124	if (addr->mode == IEEE802154_ADDR_SHORT) {
	125	pr_debug("%s is short: %04x\n", name,
	126	le16_to_cpu(addr->short_addr));
	127	} else {
	128	u64 hw = swab64((__force u64)addr->extended_addr);
	129
	130	pr_debug("%s is hardware: %8phC\n", name, &hw);
	131	}
	132	}
	133
be9d215f AA	134	static int
be9d215f AA	135	ieee802154_parse_frame_start(struct sk_buff skb, struct ieee802154_hdr hdr)
2a9820c9 AA	136	{
	137	int hlen;
	138	struct ieee802154_mac_cb *cb = mac_cb_init(skb);
	139
9cf215d0 AA	140	skb_reset_mac_header(skb);
9cf215d0 AA	141
2a9820c9 AA	142	hlen = ieee802154_hdr_pull(skb, hdr);
	143	if (hlen < 0)
	144	return -EINVAL;
	145
	146	skb->mac_len = hlen;
	147
	148	pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc),
	149	hdr->seq);
	150
	151	cb->type = hdr->fc.type;
	152	cb->ackreq = hdr->fc.ack_request;
	153	cb->secen = hdr->fc.security_enabled;
	154
be9d215f AA	155	ieee802154_print_addr("destination", &hdr->dest);
be9d215f AA	156	ieee802154_print_addr("source", &hdr->source);
2a9820c9 AA	157
	158	cb->source = hdr->source;
	159	cb->dest = hdr->dest;
	160
	161	if (hdr->fc.security_enabled) {
	162	u64 key;
	163
	164	pr_debug("seclevel %i\n", hdr->sec.level);
	165
	166	switch (hdr->sec.key_id_mode) {
	167	case IEEE802154_SCF_KEY_IMPLICIT:
	168	pr_debug("implicit key\n");
	169	break;
	170
	171	case IEEE802154_SCF_KEY_INDEX:
	172	pr_debug("key %02x\n", hdr->sec.key_id);
	173	break;
	174
	175	case IEEE802154_SCF_KEY_SHORT_INDEX:
	176	pr_debug("key %04x:%04x %02x\n",
	177	le32_to_cpu(hdr->sec.short_src) >> 16,
	178	le32_to_cpu(hdr->sec.short_src) & 0xffff,
	179	hdr->sec.key_id);
	180	break;
	181
	182	case IEEE802154_SCF_KEY_HW_INDEX:
	183	key = swab64((__force u64)hdr->sec.extended_src);
	184	pr_debug("key source %8phC %02x\n", &key,
	185	hdr->sec.key_id);
	186	break;
	187	}
	188	}
	189
	190	return 0;
	191	}
	192
	193	static void
be9d215f AA	194	__ieee802154_rx_handle_packet(struct ieee802154_local *local,
be9d215f AA	195	struct sk_buff *skb)
2a9820c9 AA	196	{
	197	int ret;
	198	struct ieee802154_sub_if_data *sdata;
	199	struct ieee802154_hdr hdr;
	200
be9d215f	201	ret = ieee802154_parse_frame_start(skb, &hdr);
2a9820c9 AA	202	if (ret) {
	203	pr_debug("got invalid frame\n");
	204	kfree_skb(skb);
	205	return;
	206	}
	207
2a9820c9	208	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1bc1754e VB	209	if (sdata->wpan_dev.iftype != NL802154_IFTYPE_NODE)
	210	continue;
	211
	212	if (!ieee802154_sdata_running(sdata))
2a9820c9 AA	213	continue;
2a9820c9 AA	214
be9d215f	215	ieee802154_subif_frame(sdata, skb, &hdr);
2a9820c9 AA	216	skb = NULL;
	217	break;
	218	}
2a9820c9	219
56f9ebe6	220	kfree_skb(skb);
2a9820c9 AA	221	}
2a9820c9 AA	222
4ca18be5	223	static void
be9d215f	224	ieee802154_monitors_rx(struct ieee802154_local local, struct sk_buff skb)
2a9820c9 AA	225	{
	226	struct sk_buff *skb2;
	227	struct ieee802154_sub_if_data *sdata;
2a9820c9	228
9cf215d0	229	skb_reset_mac_header(skb);
75a46f0e	230	skb->ip_summed = CHECKSUM_UNNECESSARY;
c9ca6401	231	skb->pkt_type = PACKET_OTHERHOST;
702dcf99 AA	232	skb->protocol = htons(ETH_P_IEEE802154);
702dcf99 AA	233
2a9820c9	234	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
ed65963b	235	if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR)
20b48120 AA	236	continue;
	237
	238	if (!ieee802154_sdata_running(sdata))
2a9820c9 AA	239	continue;
	240
	241	skb2 = skb_clone(skb, GFP_ATOMIC);
05f7de67 AA	242	if (skb2) {
	243	skb2->dev = sdata->dev;
	244	ieee802154_deliver_skb(skb2);
2a9820c9	245
05f7de67 AA	246	sdata->dev->stats.rx_packets++;
	247	sdata->dev->stats.rx_bytes += skb->len;
	248	}
2a9820c9	249	}
2a9820c9 AA	250	}
2a9820c9 AA	251
d10270ce	252	void ieee802154_rx(struct ieee802154_local local, struct sk_buff skb)
1cd829c8	253	{
ec718f3d	254	u16 crc;
1cd829c8	255
469100d6 AA	256	WARN_ON_ONCE(softirq_count() == 0);
469100d6 AA	257
3cf24cf8 AA	258	if (local->suspended)
	259	goto drop;
	260
b7889497 AA	261	/* TODO: When a transceiver omits the checksum here, we
	262	* add an own calculated one. This is currently an ugly
	263	* solution because the monitor needs a crc here.
	264	*/
	265	if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) {
ec718f3d	266	crc = crc_ccitt(0, skb->data, skb->len);
b7889497	267	put_unaligned_le16(crc, skb_put(skb, 2));
1cd829c8	268	}
1cd829c8	269
e176b681 AA	270	rcu_read_lock();
e176b681 AA	271
be9d215f	272	ieee802154_monitors_rx(local, skb);
2d3b5b0a	273
ec718f3d AA	274	/* Check if transceiver doesn't validate the checksum.
	275	* If not we validate the checksum here.
	276	*/
	277	if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) {
	278	crc = crc_ccitt(0, skb->data, skb->len);
	279	if (crc) {
	280	rcu_read_unlock();
3cf24cf8	281	goto drop;
ec718f3d AA	282	}
ec718f3d AA	283	}
b7889497 AA	284	/* remove crc */
b7889497 AA	285	skb_trim(skb, skb->len - 2);
e176b681	286
b7889497	287	__ieee802154_rx_handle_packet(local, skb);
2d3b5b0a	288
b7889497	289	rcu_read_unlock();
3cf24cf8 AA	290
	291	return;
	292	drop:
	293	kfree_skb(skb);
1cd829c8	294	}
1cd829c8	295
1cd829c8	296	void
5a504397	297	ieee802154_rx_irqsafe(struct ieee802154_hw hw, struct sk_buff skb, u8 lqi)
1cd829c8	298	{
60741361	299	struct ieee802154_local *local = hw_to_local(hw);
1cd829c8	300
c5c47e67 AA	301	mac_cb(skb)->lqi = lqi;
	302	skb->pkt_type = IEEE802154_RX_MSG;
	303	skb_queue_tail(&local->skb_queue, skb);
	304	tasklet_schedule(&local->tasklet);
1cd829c8	305	}
1cd829c8	306	EXPORT_SYMBOL(ieee802154_rx_irqsafe);