1 files changed, 109 insertions, 0 deletions
diff --git a/net/ieee802154/pan.c b/net/ieee802154/pan.c
new file mode 100644
index 0000000000..249df7364b
--- /dev/null
+++ b/net/ieee802154/pan.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IEEE 802.15.4 PAN management
+ *
+ * Copyright (C) 2023 Qorvo US, Inc
+ * Authors:
+ *   - David Girault <david.girault@qorvo.com>
+ *   - Miquel Raynal <miquel.raynal@bootlin.com>
+ */
+
+#include <linux/kernel.h>
+#include <net/cfg802154.h>
+#include <net/af_ieee802154.h>
+
+/* Checks whether a device address matches one from the PAN list.
+ * This helper is meant to be used only during PAN management, when we expect
+ * extended addresses to be used.
+ */
+static bool cfg802154_pan_device_is_matching(struct ieee802154_pan_device *pan_dev,
+					     struct ieee802154_addr *ext_dev)
+{
+	if (!pan_dev || !ext_dev)
+		return false;
+
+	if (ext_dev->mode == IEEE802154_ADDR_SHORT)
+		return false;
+
+	return pan_dev->extended_addr == ext_dev->extended_addr;
+}
+
+bool cfg802154_device_is_associated(struct wpan_dev *wpan_dev)
+{
+	bool is_assoc;
+
+	mutex_lock(&wpan_dev->association_lock);
+	is_assoc = !list_empty(&wpan_dev->children) || wpan_dev->parent;
+	mutex_unlock(&wpan_dev->association_lock);
+
+	return is_assoc;
+}
+
+bool cfg802154_device_is_parent(struct wpan_dev *wpan_dev,
+				struct ieee802154_addr *target)
+{
+	lockdep_assert_held(&wpan_dev->association_lock);
+
+	return cfg802154_pan_device_is_matching(wpan_dev->parent, target);
+}
+EXPORT_SYMBOL_GPL(cfg802154_device_is_parent);
+
+struct ieee802154_pan_device *
+cfg802154_device_is_child(struct wpan_dev *wpan_dev,
+			  struct ieee802154_addr *target)
+{
+	struct ieee802154_pan_device *child;
+
+	lockdep_assert_held(&wpan_dev->association_lock);
+
+	list_for_each_entry(child, &wpan_dev->children, node)
+		if (cfg802154_pan_device_is_matching(child, target))
+			return child;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(cfg802154_device_is_child);
+
+__le16 cfg802154_get_free_short_addr(struct wpan_dev *wpan_dev)
+{
+	struct ieee802154_pan_device *child;
+	__le16 addr;
+
+	lockdep_assert_held(&wpan_dev->association_lock);
+
+	do {
+		get_random_bytes(&addr, 2);
+		if (addr == cpu_to_le16(IEEE802154_ADDR_SHORT_BROADCAST) ||
+		    addr == cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC))
+			continue;
+
+		if (wpan_dev->short_addr == addr)
+			continue;
+
+		if (wpan_dev->parent && wpan_dev->parent->short_addr == addr)
+			continue;
+
+		list_for_each_entry(child, &wpan_dev->children, node)
+			if (child->short_addr == addr)
+				continue;
+
+		break;
+	} while (1);
+
+	return addr;
+}
+EXPORT_SYMBOL_GPL(cfg802154_get_free_short_addr);
+
+unsigned int cfg802154_set_max_associations(struct wpan_dev *wpan_dev,
+					    unsigned int max)
+{
+	unsigned int old_max;
+
+	lockdep_assert_held(&wpan_dev->association_lock);
+
+	old_max = wpan_dev->max_associations;
+	wpan_dev->max_associations = max;
+
+	return old_max;
+}
+EXPORT_SYMBOL_GPL(cfg802154_set_max_associations);