nl80211: vendor command support

Add support for vendor-specific commands to nl80211. This is
intended to be used for really vendor-specific functionality
that can't be implemented in a generic fashion for any reason.
It's *NOT* intended to be used for any normal/generic feature
or any optimisations that could be implemented across drivers.

Currently, only vendor commands (with replies) are supported,
no dump operations or vendor-specific notifications.

Also add a function wdev_to_ieee80211_vif() to mac80211 which
is needed for mac80211-based drivers wanting to implement any
vendor commands.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 170 insertions, 71 deletions

diff --git a/net/wireless/core.h b/net/wireless/core.h
index 6716c5c..ac77644 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -67,9 +67,7 @@ struct cfg80211_registered_device {
 	struct work_struct scan_done_wk;
 	struct work_struct sched_scan_results_wk;
 
-#ifdef CONFIG_NL80211_TESTMODE
-	struct genl_info *testmode_info;
-#endif
+	struct genl_info *cur_cmd_info;
 
 	struct work_struct conn_work;
 	struct work_struct event_work;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index bdcf256..6989989 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -358,6 +358,9 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
 	[NL80211_ATTR_STA_SUPPORTED_OPER_CLASSES] = { .type = NLA_BINARY },
 	[NL80211_ATTR_HANDLE_DFS] = { .type = NLA_FLAG },
 	[NL80211_ATTR_OPMODE_NOTIF] = { .type = NLA_U8 },
+	[NL80211_ATTR_VENDOR_ID] = { .type = NLA_U32 },
+	[NL80211_ATTR_VENDOR_SUBCMD] = { .type = NLA_U32 },
+	[NL80211_ATTR_VENDOR_DATA] = { .type = NLA_BINARY },
 };
 
 /* policy for the key attributes */
@@ -1166,6 +1169,7 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *dev,
 	struct nlattr *nl_bands, *nl_band;
 	struct nlattr *nl_freqs, *nl_freq;
 	struct nlattr *nl_cmds;
+	struct nlattr *nl_vendor_cmds;
 	enum ieee80211_band band;
 	struct ieee80211_channel *chan;
 	int i;
@@ -1561,6 +1565,19 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *dev,
 		    (nla_put_flag(msg, NL80211_ATTR_SUPPORT_5_MHZ) ||
 		     nla_put_flag(msg, NL80211_ATTR_SUPPORT_10_MHZ)))
 			goto nla_put_failure;
+		state->split_start++;
+		break;
+	case 11:
+		nl_vendor_cmds = nla_nest_start(msg, NL80211_ATTR_VENDOR_DATA);
+		if (!nl_vendor_cmds)
+			goto nla_put_failure;
+
+		for (i = 0; i < dev->wiphy.n_vendor_commands; i++)
+			if (nla_put(msg, i + 1,
+				    sizeof(struct nl80211_vendor_cmd_info),
+				    &dev->wiphy.vendor_commands[i].info))
+				goto nla_put_failure;
+		nla_nest_end(msg, nl_vendor_cmds);
 
 		/* done */
 		state->split_start = 0;
@@ -6682,6 +6699,40 @@ static int nl80211_set_mcast_rate(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static struct sk_buff *
+__cfg80211_alloc_vendor_skb(struct cfg80211_registered_device *rdev,
+			    int approxlen, u32 portid, u32 seq,
+			    enum nl80211_commands cmd,
+			    enum nl80211_attrs attr, gfp_t gfp)
+{
+	struct sk_buff *skb;
+	void *hdr;
+	struct nlattr *data;
+
+	skb = nlmsg_new(approxlen + 100, gfp);
+	if (!skb)
+		return NULL;
+
+	hdr = nl80211hdr_put(skb, portid, seq, 0, cmd);
+	if (!hdr) {
+		kfree_skb(skb);
+		return NULL;
+	}
+
+	if (nla_put_u32(skb, NL80211_ATTR_WIPHY, rdev->wiphy_idx))
+		goto nla_put_failure;
+	data = nla_nest_start(skb, attr);
+
+	((void **)skb->cb)[0] = rdev;
+	((void **)skb->cb)[1] = hdr;
+	((void **)skb->cb)[2] = data;
+
+	return skb;
+
+ nla_put_failure:
+	kfree_skb(skb);
+	return NULL;
+}
 
 #ifdef CONFIG_NL80211_TESTMODE
 static struct genl_multicast_group nl80211_testmode_mcgrp = {
@@ -6710,11 +6761,11 @@ static int nl80211_testmode_do(struct sk_buff *skb, struct genl_info *info)
 	if (!info->attrs[NL80211_ATTR_TESTDATA])
 		return -EINVAL;
 
-	rdev->testmode_info = info;
+	rdev->cur_cmd_info = info;
 	err = rdev_testmode_cmd(rdev, wdev,
 				nla_data(info->attrs[NL80211_ATTR_TESTDATA]),
 				nla_len(info->attrs[NL80211_ATTR_TESTDATA]));
-	rdev->testmode_info = NULL;
+	rdev->cur_cmd_info = NULL;
 
 	return err;
 }
@@ -6814,77 +6865,14 @@ static int nl80211_testmode_dump(struct sk_buff *skb,
 	return err;
 }
 
-static struct sk_buff *
-__cfg80211_testmode_alloc_skb(struct cfg80211_registered_device *rdev,
-			      int approxlen, u32 portid, u32 seq, gfp_t gfp)
-{
-	struct sk_buff *skb;
-	void *hdr;
-	struct nlattr *data;
-
-	skb = nlmsg_new(approxlen + 100, gfp);
-	if (!skb)
-		return NULL;
-
-	hdr = nl80211hdr_put(skb, portid, seq, 0, NL80211_CMD_TESTMODE);
-	if (!hdr) {
-		kfree_skb(skb);
-		return NULL;
-	}
-
-	if (nla_put_u32(skb, NL80211_ATTR_WIPHY, rdev->wiphy_idx))
-		goto nla_put_failure;
-	data = nla_nest_start(skb, NL80211_ATTR_TESTDATA);
-
-	((void **)skb->cb)[0] = rdev;
-	((void **)skb->cb)[1] = hdr;
-	((void **)skb->cb)[2] = data;
-
-	return skb;
-
- nla_put_failure:
-	kfree_skb(skb);
-	return NULL;
-}
-
-struct sk_buff *cfg80211_testmode_alloc_reply_skb(struct wiphy *wiphy,
-						  int approxlen)
-{
-	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
-
-	if (WARN_ON(!rdev->testmode_info))
-		return NULL;
-
-	return __cfg80211_testmode_alloc_skb(rdev, approxlen,
-				rdev->testmode_info->snd_portid,
-				rdev->testmode_info->snd_seq,
-				GFP_KERNEL);
-}
-EXPORT_SYMBOL(cfg80211_testmode_alloc_reply_skb);
-
-int cfg80211_testmode_reply(struct sk_buff *skb)
-{
-	struct cfg80211_registered_device *rdev = ((void **)skb->cb)[0];
-	void *hdr = ((void **)skb->cb)[1];
-	struct nlattr *data = ((void **)skb->cb)[2];
-
-	if (WARN_ON(!rdev->testmode_info)) {
-		kfree_skb(skb);
-		return -EINVAL;
-	}
-
-	nla_nest_end(skb, data);
-	genlmsg_end(skb, hdr);
-	return genlmsg_reply(skb, rdev->testmode_info);
-}
-EXPORT_SYMBOL(cfg80211_testmode_reply);
-
 struct sk_buff *cfg80211_testmode_alloc_event_skb(struct wiphy *wiphy,
 						  int approxlen, gfp_t gfp)
 {
 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 
-	return __cfg80211_testmode_alloc_skb(rdev, approxlen, 0, 0, gfp);
+	return __cfg80211_alloc_vendor_skb(rdev, approxlen, 0, 0,
+					   NL80211_CMD_TESTMODE,
+					   NL80211_ATTR_TESTDATA, gfp);
 }
 EXPORT_SYMBOL(cfg80211_testmode_alloc_event_skb);
 
@@ -8867,6 +8855,111 @@ static int nl80211_crit_protocol_stop(struct sk_buff *skb,
 	return 0;
 }
 
+static int nl80211_vendor_cmd(struct sk_buff *skb, struct genl_info *info)
+{
+	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+	struct wireless_dev *wdev =
+		__cfg80211_wdev_from_attrs(genl_info_net(info), info->attrs);
+	int i, err;
+	u32 vid, subcmd;
+
+	if (!rdev->wiphy.vendor_commands)
+		return -EOPNOTSUPP;
+
+	if (IS_ERR(wdev)) {
+		err = PTR_ERR(wdev);
+		if (err != -EINVAL)
+			return err;
+		wdev = NULL;
+	} else if (wdev->wiphy != &rdev->wiphy) {
+		return -EINVAL;
+	}
+
+	if (!info->attrs[NL80211_ATTR_VENDOR_ID] ||
+	    !info->attrs[NL80211_ATTR_VENDOR_SUBCMD])
+		return -EINVAL;
+
+	vid = nla_get_u32(info->attrs[NL80211_ATTR_VENDOR_ID]);
+	subcmd = nla_get_u32(info->attrs[NL80211_ATTR_VENDOR_SUBCMD]);
+	for (i = 0; i < rdev->wiphy.n_vendor_commands; i++) {
+		const struct wiphy_vendor_command *vcmd;
+		void *data = NULL;
+		int len = 0;
+
+		vcmd = &rdev->wiphy.vendor_commands[i];
+
+		if (vcmd->info.vendor_id != vid || vcmd->info.subcmd != subcmd)
+			continue;
+
+		if (vcmd->flags & (WIPHY_VENDOR_CMD_NEED_WDEV |
+				   WIPHY_VENDOR_CMD_NEED_NETDEV)) {
+			if (!wdev)
+				return -EINVAL;
+			if (vcmd->flags & WIPHY_VENDOR_CMD_NEED_NETDEV &&
+			    !wdev->netdev)
+				return -EINVAL;
+
+			if (vcmd->flags & WIPHY_VENDOR_CMD_NEED_RUNNING) {
+				if (wdev->netdev &&
+				    !netif_running(wdev->netdev))
+					return -ENETDOWN;
+				if (!wdev->netdev && !wdev->p2p_started)
+					return -ENETDOWN;
+			}
+		} else {
+			wdev = NULL;
+		}
+
+		if (info->attrs[NL80211_ATTR_VENDOR_DATA]) {
+			data = nla_data(info->attrs[NL80211_ATTR_VENDOR_DATA]);
+			len = nla_len(info->attrs[NL80211_ATTR_VENDOR_DATA]);
+		}
+
+		rdev->cur_cmd_info = info;
+		err = rdev->wiphy.vendor_commands[i].doit(&rdev->wiphy, wdev,
+							  data, len);
+		rdev->cur_cmd_info = NULL;
+		return err;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+struct sk_buff *__cfg80211_alloc_reply_skb(struct wiphy *wiphy,
+					   enum nl80211_commands cmd,
+					   enum nl80211_attrs attr,
+					   int approxlen)
+{
+	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
+
+	if (WARN_ON(!rdev->cur_cmd_info))
+		return NULL;
+
+	return __cfg80211_alloc_vendor_skb(rdev, approxlen,
+					   rdev->cur_cmd_info->snd_portid,
+					   rdev->cur_cmd_info->snd_seq,
+					   cmd, attr, GFP_KERNEL);
+}
+EXPORT_SYMBOL(__cfg80211_alloc_reply_skb);
+
+int cfg80211_vendor_cmd_reply(struct sk_buff *skb)
+{
+	struct cfg80211_registered_device *rdev = ((void **)skb->cb)[0];
+	void *hdr = ((void **)skb->cb)[1];
+	struct nlattr *data = ((void **)skb->cb)[2];
+
+	if (WARN_ON(!rdev->cur_cmd_info)) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
+
+	nla_nest_end(skb, data);
+	genlmsg_end(skb, hdr);
+	return genlmsg_reply(skb, rdev->cur_cmd_info);
+}
+EXPORT_SYMBOL_GPL(cfg80211_vendor_cmd_reply);
+
+
 #define NL80211_FLAG_NEED_WIPHY		0x01
 #define NL80211_FLAG_NEED_NETDEV	0x02
 #define NL80211_FLAG_NEED_RTNL		0x04
@@ -9591,6 +9684,14 @@ static struct genl_ops nl80211_ops[] = {
 		.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
 				  NL80211_FLAG_NEED_RTNL,
 	},
+	{
+		.cmd = NL80211_CMD_VENDOR,
+		.doit = nl80211_vendor_cmd,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = NL80211_FLAG_NEED_WIPHY |
+				  NL80211_FLAG_NEED_RTNL,
+	},
 };
 
 static struct genl_multicast_group nl80211_mlme_mcgrp = {