nl80211: export supported commands

This makes nl80211 export the supported commands (command groups)
per wiphy so userspace has an idea what it can do -- this will be
required reading for userspace when we introduce auth/assoc /or/
connect for older hardware that cannot separate auth and assoc.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/linux/nl80211.h

@@ -349,6 +349,10 @@ enum nl80211_commands {
  * @NL80211_ATTR_REG_TYPE: indicates the type of the regulatory domain currently
  * 	set. This can be one of the nl80211_reg_type (%NL80211_REGDOM_TYPE_*)
  *
+ * @NL80211_ATTR_SUPPORTED_COMMANDS: wiphy attribute that specifies
+ *	an array of command numbers (i.e. a mapping index to command number)
+ *	that the driver for the given wiphy supports.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -426,6 +430,8 @@ enum nl80211_attrs {
 	NL80211_ATTR_REG_INITIATOR,
 	NL80211_ATTR_REG_TYPE,
 
+	NL80211_ATTR_SUPPORTED_COMMANDS,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,

net/wireless/nl80211.c

@@ -131,6 +131,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 	struct nlattr *nl_freqs, *nl_freq;
 	struct nlattr *nl_rates, *nl_rate;
 	struct nlattr *nl_modes;
+	struct nlattr *nl_cmds;
 	enum ieee80211_band band;
 	struct ieee80211_channel *chan;
 	struct ieee80211_rate *rate;
@@ -242,6 +243,32 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 	}
 	nla_nest_end(msg, nl_bands);
 
+	nl_cmds = nla_nest_start(msg, NL80211_ATTR_SUPPORTED_COMMANDS);
+	if (!nl_cmds)
+		goto nla_put_failure;
+
+	i = 0;
+#define CMD(op, n)						\
+	 do {							\
+		if (dev->ops->op) {				\
+			i++;					\
+			NLA_PUT_U32(msg, i, NL80211_CMD_ ## n);	\
+		}						\
+	} while (0)
+
+	CMD(add_virtual_intf, NEW_INTERFACE);
+	CMD(change_virtual_intf, SET_INTERFACE);
+	CMD(add_key, NEW_KEY);
+	CMD(add_beacon, NEW_BEACON);
+	CMD(add_station, NEW_STATION);
+	CMD(add_mpath, NEW_MPATH);
+	CMD(set_mesh_params, SET_MESH_PARAMS);
+	CMD(change_bss, SET_BSS);
+	CMD(set_mgmt_extra_ie, SET_MGMT_EXTRA_IE);
+
+#undef CMD
+	nla_nest_end(msg, nl_cmds);
+
 	return genlmsg_end(msg, hdr);
 
  nla_put_failure: