ethtool: add WOL_NTF notification

Send ETHTOOL_MSG_WOL_NTF notification whenever wake-on-lan settings of
a device are modified using ETHTOOL_MSG_WOL_SET netlink message or
ETHTOOL_SWOL ioctl request.

As notifications can be received by anyone, do not include SecureOn(tm)
password in notification messages.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/ethtool-netlink.rst

@@ -193,7 +193,7 @@ Userspace to kernel:
 
 Kernel to userspace:
 
-  ===================================== ================================
+  ===================================== =================================
   ``ETHTOOL_MSG_STRSET_GET_REPLY``      string set contents
   ``ETHTOOL_MSG_LINKINFO_GET_REPLY``    link settings
   ``ETHTOOL_MSG_LINKINFO_NTF``          link settings notification
@@ -203,7 +203,8 @@ Kernel to userspace:
   ``ETHTOOL_MSG_DEBUG_GET_REPLY``       debugging settings
   ``ETHTOOL_MSG_DEBUG_NTF``             debugging settings notification
   ``ETHTOOL_MSG_WOL_GET_REPLY``         wake-on-lan settings
-  ===================================== ================================
+  ``ETHTOOL_MSG_WOL_NTF``               wake-on-lan settings notification
+  ===================================== =================================
 
 ``GET`` requests are sent by userspace applications to retrieve device
 information. They usually do not contain any message specific attributes.

include/uapi/linux/ethtool_netlink.h

@@ -42,6 +42,7 @@ enum {
 	ETHTOOL_MSG_DEBUG_GET_REPLY,
 	ETHTOOL_MSG_DEBUG_NTF,
 	ETHTOOL_MSG_WOL_GET_REPLY,
+	ETHTOOL_MSG_WOL_NTF,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_KERNEL_CNT,

net/ethtool/ioctl.c

@@ -1316,6 +1316,7 @@ static int ethtool_set_wol(struct net_device *dev, char __user *useraddr)
 		return ret;
 
 	dev->wol_enabled = !!wol.wolopts;
+	ethtool_notify(dev, ETHTOOL_MSG_WOL_NTF, NULL);
 
 	return 0;
 }

net/ethtool/netlink.c

@@ -526,6 +526,7 @@ ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
 	[ETHTOOL_MSG_LINKINFO_NTF]	= &ethnl_linkinfo_request_ops,
 	[ETHTOOL_MSG_LINKMODES_NTF]	= &ethnl_linkmodes_request_ops,
 	[ETHTOOL_MSG_DEBUG_NTF]		= &ethnl_debug_request_ops,
+	[ETHTOOL_MSG_WOL_NTF]		= &ethnl_wol_request_ops,
 };
 
 /* default notification handler */
@@ -610,6 +611,7 @@ static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
 	[ETHTOOL_MSG_LINKINFO_NTF]	= ethnl_default_notify,
 	[ETHTOOL_MSG_LINKMODES_NTF]	= ethnl_default_notify,
 	[ETHTOOL_MSG_DEBUG_NTF]		= ethnl_default_notify,
+	[ETHTOOL_MSG_WOL_NTF]		= ethnl_default_notify,
 };
 
 void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)

net/ethtool/wol.c

@@ -41,7 +41,8 @@ static int wol_prepare_data(const struct ethnl_req_info *req_base,
 		return ret;
 	dev->ethtool_ops->get_wol(dev, &data->wol);
 	ethnl_ops_complete(dev);
-	data->show_sopass = data->wol.supported & WAKE_MAGICSECURE;
+	/* do not include password in notifications */
+	data->show_sopass = info && (data->wol.supported & WAKE_MAGICSECURE);
 
 	return 0;
 }
@@ -165,6 +166,7 @@ int ethnl_set_wol(struct sk_buff *skb, struct genl_info *info)
 	if (ret)
 		goto out_ops;
 	dev->wol_enabled = !!wol.wolopts;
+	ethtool_notify(dev, ETHTOOL_MSG_WOL_NTF, NULL);
 
 out_ops:
 	ethnl_ops_complete(dev);