redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity
alistair23-linux/net/mac802154/rx.c
Alexander Aring c947f7e1e3 mac802154: remove mib lock 
This patch removes the mib lock. The new locking mechanism is to protect
the mib values with the rtnl lock. Note that this isn't always necessary
if we have an interface up the most mib values are readonly (e.g.
address settings). With this behaviour we can remove locking in
hotpath like frame parsing completely. It depends on context if we need
to hold the rtnl lock or not, this makes the callbacks of
ieee802154_mlme_ops unnecessary because these callbacks hols always the
locks.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-05-23 17:57:08 +02:00

298 lines
7.2 KiB
C
Raw Blame History

/*
* 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;
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->vif.type != NL802154_IFTYPE_NODE ||
!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;
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->vif.type != 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_hw *hw, struct sk_buff *skb)
{
struct ieee802154_local *local = hw_to_local(hw);
u16 crc;
WARN_ON_ONCE(softirq_count() == 0);
/* 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();
kfree_skb(skb);
return;
}
}
/* remove crc */
skb_trim(skb, skb->len - 2);
__ieee802154_rx_handle_packet(local, skb);
rcu_read_unlock();
}
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);
View git blame Copy permalink