forked from luck/tmp_suning_uos_patched
mac80211: add utility function to get header length
Take a __le16 directly rather than a host-endian value. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
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@ -1547,6 +1547,12 @@ unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb);
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*/
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int ieee80211_get_hdrlen(u16 fc);
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/**
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* ieee80211_hdrlen - get header length in bytes from frame control
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* @fc: frame control field in little-endian format
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*/
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unsigned int ieee80211_hdrlen(__le16 fc);
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/**
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* ieee80211_get_tkip_key - get a TKIP rc4 for skb
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*
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@ -133,6 +133,38 @@ int ieee80211_get_hdrlen(u16 fc)
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}
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EXPORT_SYMBOL(ieee80211_get_hdrlen);
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unsigned int ieee80211_hdrlen(__le16 fc)
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{
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unsigned int hdrlen = 24;
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if (ieee80211_is_data(fc)) {
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if (ieee80211_has_a4(fc))
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hdrlen = 30;
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if (ieee80211_is_data_qos(fc))
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hdrlen += IEEE80211_QOS_CTL_LEN;
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goto out;
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}
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if (ieee80211_is_ctl(fc)) {
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/*
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* ACK and CTS are 10 bytes, all others 16. To see how
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* to get this condition consider
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* subtype mask: 0b0000000011110000 (0x00F0)
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* ACK subtype: 0b0000000011010000 (0x00D0)
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* CTS subtype: 0b0000000011000000 (0x00C0)
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* bits that matter: ^^^ (0x00E0)
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* value of those: 0b0000000011000000 (0x00C0)
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*/
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if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
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hdrlen = 10;
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else
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hdrlen = 16;
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}
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out:
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return hdrlen;
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}
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EXPORT_SYMBOL(ieee80211_hdrlen);
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unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
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{
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const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *)skb->data;
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