nl80211: refactor valid channel type check

There are four instances in nl80211 of getting the
channel type from the attribute and validating it,
refactor those.

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

1 files changed, 29 insertions, 30 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f1b0774d098b..206465dc0cab 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1179,6 +1179,27 @@ static bool nl80211_can_set_dev_channel(struct wireless_dev *wdev)
                 wdev->iftype == NL80211_IFTYPE_P2P_GO;
 }
 
+static bool nl80211_valid_channel_type(struct genl_info *info,
+                                       enum nl80211_channel_type *channel_type)
+{
+        enum nl80211_channel_type tmp;
+
+        if (!info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE])
+                return false;
+
+        tmp = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
+        if (tmp != NL80211_CHAN_NO_HT &&
+            tmp != NL80211_CHAN_HT20 &&
+            tmp != NL80211_CHAN_HT40PLUS &&
+            tmp != NL80211_CHAN_HT40MINUS)
+                return false;
+
+        if (channel_type)
+                *channel_type = tmp;
+
+        return true;
+}
+
 static int __nl80211_set_channel(struct cfg80211_registered_device *rdev,
                                  struct wireless_dev *wdev,
                                  struct genl_info *info)
@@ -1193,15 +1214,9 @@ static int __nl80211_set_channel(struct cfg80211_registered_device *rdev,
         if (!nl80211_can_set_dev_channel(wdev))
                 return -EOPNOTSUPP;
 
-        if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) {
-                channel_type = nla_get_u32(info->attrs[
-                                   NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
-                if (channel_type != NL80211_CHAN_NO_HT &&
-                    channel_type != NL80211_CHAN_HT20 &&
-                    channel_type != NL80211_CHAN_HT40PLUS &&
-                    channel_type != NL80211_CHAN_HT40MINUS)
-                        return -EINVAL;
-        }
+        if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE] &&
+            !nl80211_valid_channel_type(info, &channel_type))
+                return -EINVAL;
 
         freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]);
 
@@ -4918,12 +4933,7 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
         if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) {
                 enum nl80211_channel_type channel_type;
 
-                channel_type = nla_get_u32(
-                                info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
-                if (channel_type != NL80211_CHAN_NO_HT &&
-                    channel_type != NL80211_CHAN_HT20 &&
-                    channel_type != NL80211_CHAN_HT40MINUS &&
-                    channel_type != NL80211_CHAN_HT40PLUS)
+                if (!nl80211_valid_channel_type(info, &channel_type))
                         return -EINVAL;
 
                 if (channel_type != NL80211_CHAN_NO_HT &&
@@ -5491,15 +5501,9 @@ static int nl80211_remain_on_channel(struct sk_buff *skb,
             !(rdev->wiphy.flags & WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL))
                 return -EOPNOTSUPP;
 
-        if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) {
-                channel_type = nla_get_u32(
-                        info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
-                if (channel_type != NL80211_CHAN_NO_HT &&
-                    channel_type != NL80211_CHAN_HT20 &&
-                    channel_type != NL80211_CHAN_HT40PLUS &&
-                    channel_type != NL80211_CHAN_HT40MINUS)
-                        return -EINVAL;
-        }
+        if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE] &&
+            !nl80211_valid_channel_type(info, &channel_type))
+                return -EINVAL;
 
         freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]);
         chan = rdev_freq_to_chan(rdev, freq, channel_type);
@@ -5770,12 +5774,7 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info)
         }
 
         if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) {
-                channel_type = nla_get_u32(
-                        info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
-                if (channel_type != NL80211_CHAN_NO_HT &&
-                    channel_type != NL80211_CHAN_HT20 &&
-                    channel_type != NL80211_CHAN_HT40PLUS &&
-                    channel_type != NL80211_CHAN_HT40MINUS)
+                if (!nl80211_valid_channel_type(info, &channel_type))
                         return -EINVAL;
                 channel_type_valid = true;
         }