diff options
| author | Alexander Aring <alex.aring@gmail.com> | 2014-10-29 23:34:36 +0300 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2014-10-30 01:07:45 +0300 |
| commit | b7889497d306df0be52300b3060ebc12b4194f9a (patch) | |
| tree | ee2f0a995b2e5579f63960a47f2f519dbffa326e /net/mac802154 | |
| parent | 08c511a7331cf6edb28895d7f46c3039180b30cb (diff) | |
| download | linux-b7889497d306df0be52300b3060ebc12b4194f9a.tar.xz | |
mac802154: rx: simplify crc receive handling
This patch change the actual crc handling while receive. Currently the
IEEE802154_HW_RX_OMIT_CKSUM flag is used to filter a frame with a bad crc.
This patch changes the behaviour of IEEE802154_HW_RX_OMIT_CKSUM to add a
crc while receiving for the monitor interface. After monitor receiving
we remove the crc for frame parsing. This affect the driver layer
because all drivers sets IEEE802154_HW_RX_OMIT_CKSUM and deliver without
checksum.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net/mac802154')
| -rw-r--r-- | net/mac802154/rx.c | 34 |
1 files changed, 12 insertions, 22 deletions
diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c index 51a55d9200cb..b6a4bbfdbf90 100644 --- a/net/mac802154/rx.c +++ b/net/mac802154/rx.c @@ -21,6 +21,7 @@ #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> @@ -225,8 +226,6 @@ 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; @@ -241,9 +240,6 @@ ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb) 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); } @@ -255,32 +251,26 @@ void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb) WARN_ON_ONCE(softirq_count() == 0); - if (!(local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM)) { - u16 crc; + /* 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) { + u16 crc = crc_ccitt(0, skb->data, skb->len); - 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 */ + put_unaligned_le16(crc, skb_put(skb, 2)); } rcu_read_lock(); ieee802154_monitors_rx(local, skb); - __ieee802154_rx_handle_packet(local, skb); - rcu_read_unlock(); + /* remove crc */ + skb_trim(skb, skb->len - 2); - return; + __ieee802154_rx_handle_packet(local, skb); -fail: - kfree_skb(skb); + rcu_read_unlock(); } EXPORT_SYMBOL(ieee802154_rx); |