ieee802154: introduce wpan_dev_header_ops
The current header_ops callback structure of net device are used mostly
from 802.15.4 upper-layers. Because this callback structure is a very
generic one, which is also used by e.g. DGRAM AF_PACKET sockets, we
can't make this callback structure 802.15.4 specific which is currently
is.
I saw the smallest "constraint" for calling this callback with
dev_hard_header/dev_parse_header by AF_PACKET which assign a 8 byte
array for address void pointers. Currently 802.15.4 specific protocols
like af802154 and 6LoWPAN will assign the "struct ieee802154_addr" as
these parameters which is greater than 8 bytes. The current callback
implementation for header_ops.create assumes always a complete
"struct ieee802154_addr" which AF_PACKET can't never handled and is
greater than 8 bytes.
For that reason we introduce now a "generic" create/parse header_ops
callback which allows handling with intra-pan extended addresses only.
This allows a small use-case with AF_PACKET to send "somehow" a valid
dataframe over DGRAM.
To keeping the current dev_hard_header behaviour we introduce a similar
callback structure "wpan_dev_header_ops" which contains 802.15.4 specific
upper-layer header creation functionality, which can be called by
wpan_dev_hard_header.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/cfg802154.h b/include/net/cfg802154.h
index 76b1ffa..242273c 100644
--- a/include/net/cfg802154.h
+++ b/include/net/cfg802154.h
@@ -167,6 +167,26 @@
char priv[0] __aligned(NETDEV_ALIGN);
};
+struct ieee802154_addr {
+ u8 mode;
+ __le16 pan_id;
+ union {
+ __le16 short_addr;
+ __le64 extended_addr;
+ };
+};
+
+struct wpan_dev_header_ops {
+ /* TODO create callback currently assumes ieee802154_mac_cb inside
+ * skb->cb. This should be changed to give these information as
+ * parameter.
+ */
+ int (*create)(struct sk_buff *skb, struct net_device *dev,
+ const struct ieee802154_addr *daddr,
+ const struct ieee802154_addr *saddr,
+ unsigned int len);
+};
+
struct wpan_dev {
struct wpan_phy *wpan_phy;
int iftype;
@@ -175,6 +195,8 @@
struct list_head list;
struct net_device *netdev;
+ const struct wpan_dev_header_ops *header_ops;
+
/* lowpan interface, set when the wpan_dev belongs to one lowpan_dev */
struct net_device *lowpan_dev;
@@ -205,6 +227,17 @@
#define to_phy(_dev) container_of(_dev, struct wpan_phy, dev)
+static inline int
+wpan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
+ const struct ieee802154_addr *daddr,
+ const struct ieee802154_addr *saddr,
+ unsigned int len)
+{
+ struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
+
+ return wpan_dev->header_ops->create(skb, dev, daddr, saddr, len);
+}
+
struct wpan_phy *
wpan_phy_new(const struct cfg802154_ops *ops, size_t priv_size);
static inline void wpan_phy_set_dev(struct wpan_phy *phy, struct device *dev)