cfg80211: assimilate and export ieee80211_bss_get_ie

This function from mac80211 seems generally useful, and
I will need it in cfg80211 soon.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 25550692dda6..28f8f96801d4 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -502,3 +502,24 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb)
         return dscp >> 5;
 }
 EXPORT_SYMBOL(cfg80211_classify8021d);
+
+const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
+{
+        u8 *end, *pos;
+
+        pos = bss->information_elements;
+        if (pos == NULL)
+                return NULL;
+        end = pos + bss->len_information_elements;
+
+        while (pos + 1 < end) {
+                if (pos + 2 + pos[1] > end)
+                        break;
+                if (pos[0] == ie)
+                        return pos;
+                pos += 2 + pos[1];
+        }
+
+        return NULL;
+}
+EXPORT_SYMBOL(ieee80211_bss_get_ie);