alistair23-linux/net/mac802154/rx.c
Alexander Aring 90386a7e3b mac802154: separate omit tx/rx flags
This patch splits the IEEE802154_HW_OMIT_CKSUM hardware flag into
IEEE802154_HW_TX_OMIT_CKSUM and IEEE802154_HW_RX_OMIT_CKSUM. This is
useful to deliver the received crc from the driver layer to the monitor
interface. At the moment we can't do that without change the xmit
handling.

The received checksum should be visible in monitor mode only.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-10-29 23:07:45 +01:00

298 lines
7 KiB
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 <net/mac802154.h>
#include <net/ieee802154_netdev.h>
#include <net/rtnetlink.h>
#include <linux/nl802154.h>
#include "ieee802154_i.h"
static int ieee802154_deliver_skb(struct net_device *dev, 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)
{
__le16 span, sshort;
int rc;
pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
spin_lock_bh(&sdata->mib_lock);
span = sdata->pan_id;
sshort = sdata->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 == sdata->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:
spin_unlock_bh(&sdata->mib_lock);
pr_debug("invalid dest mode\n");
kfree_skb(skb);
return NET_RX_DROP;
}
spin_unlock_bh(&sdata->mib_lock);
skb->dev = sdata->dev;
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(sdata->dev, 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->type != IEEE802154_DEV_WPAN ||
!netif_running(sdata->dev))
continue;
ieee802154_subif_frame(sdata, skb, &hdr);
skb = NULL;
break;
}
if (skb)
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;
u16 crc = crc_ccitt(0, skb->data, skb->len);
u8 *data;
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->type != IEEE802154_DEV_MONITOR ||
!netif_running(sdata->dev))
continue;
skb2 = skb_clone(skb, GFP_ATOMIC);
skb2->dev = sdata->dev;
skb2->pkt_type = PACKET_HOST;
data = skb_put(skb2, 2);
data[0] = crc & 0xff;
data[1] = crc >> 8;
netif_rx_ni(skb2);
}
}
void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb)
{
struct ieee802154_local *local = hw_to_local(hw);
WARN_ON_ONCE(softirq_count() == 0);
if (!(local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM)) {
u16 crc;
if (skb->len < 2) {
pr_debug("got invalid frame\n");
goto fail;
}
crc = crc_ccitt(0, skb->data, skb->len);
if (crc) {
pr_debug("CRC mismatch\n");
goto fail;
}
skb_trim(skb, skb->len - 2); /* CRC */
}
rcu_read_lock();
ieee802154_monitors_rx(local, skb);
__ieee802154_rx_handle_packet(local, skb);
rcu_read_unlock();
return;
fail:
kfree_skb(skb);
}
EXPORT_SYMBOL(ieee802154_rx);
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);