From ec718f3db9b7968ca5dfb10c85c56ff27149df94 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Wed, 29 Oct 2014 21:34:37 +0100 Subject: [PATCH] mac802154: rx: add software checksum filtering check This patch adds a new hardware flag which indicate that the transceiver doesn't support check for bad checksum via hardware. Also add a handling of this while receive. Signed-off-by: Alexander Aring Signed-off-by: Marcel Holtmann --- include/net/mac802154.h | 2 ++ net/mac802154/rx.c | 15 +++++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/include/net/mac802154.h b/include/net/mac802154.h index bc1d40c826e3..8f1de6844cb0 100644 --- a/include/net/mac802154.h +++ b/include/net/mac802154.h @@ -96,6 +96,8 @@ struct ieee802154_hw { #define IEEE802154_HW_PROMISCUOUS 0x00000200 /* Indicates that receiver omits FCS. */ #define IEEE802154_HW_RX_OMIT_CKSUM 0x00000400 +/* Indicates that receiver will not filter frames with bad checksum. */ +#define IEEE802154_HW_RX_DROP_BAD_CKSUM 0x00000800 /* Indicates that receiver omits FCS and xmitter will add FCS on it's own. */ #define IEEE802154_HW_OMIT_CKSUM (IEEE802154_HW_TX_OMIT_CKSUM | \ diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c index b6a4bbfdbf90..c9f1c72a1afc 100644 --- a/net/mac802154/rx.c +++ b/net/mac802154/rx.c @@ -248,6 +248,7 @@ ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb) 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); @@ -256,8 +257,7 @@ void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb) * 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); - + crc = crc_ccitt(0, skb->data, skb->len); put_unaligned_le16(crc, skb_put(skb, 2)); } @@ -265,6 +265,17 @@ void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb) 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); -- 2.20.1