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/net/mac802154/iface.c b/net/mac802154/iface.c
index ed26952..8afe26d 100644
--- a/net/mac802154/iface.c
+++ b/net/mac802154/iface.c
@@ -367,12 +367,11 @@
return 0;
}
-static int mac802154_header_create(struct sk_buff *skb,
- struct net_device *dev,
- unsigned short type,
- const void *daddr,
- const void *saddr,
- unsigned len)
+static int ieee802154_header_create(struct sk_buff *skb,
+ struct net_device *dev,
+ const struct ieee802154_addr *daddr,
+ const struct ieee802154_addr *saddr,
+ unsigned len)
{
struct ieee802154_hdr hdr;
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
@@ -423,24 +422,91 @@
return hlen;
}
+static const struct wpan_dev_header_ops ieee802154_header_ops = {
+ .create = ieee802154_header_create,
+};
+
+/* This header create functionality assumes a 8 byte array for
+ * source and destination pointer at maximum. To adapt this for
+ * the 802.15.4 dataframe header we use extended address handling
+ * here only and intra pan connection. fc fields are mostly fallback
+ * handling. For provide dev_hard_header for dgram sockets.
+ */
+static int mac802154_header_create(struct sk_buff *skb,
+ struct net_device *dev,
+ unsigned short type,
+ const void *daddr,
+ const void *saddr,
+ unsigned len)
+{
+ struct ieee802154_hdr hdr;
+ struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
+ struct wpan_dev *wpan_dev = &sdata->wpan_dev;
+ struct ieee802154_mac_cb cb = { };
+ int hlen;
+
+ if (!daddr)
+ return -EINVAL;
+
+ memset(&hdr.fc, 0, sizeof(hdr.fc));
+ hdr.fc.type = IEEE802154_FC_TYPE_DATA;
+ hdr.fc.ack_request = wpan_dev->ackreq;
+ hdr.seq = atomic_inc_return(&dev->ieee802154_ptr->dsn) & 0xFF;
+
+ /* TODO currently a workaround to give zero cb block to set
+ * security parameters defaults according MIB.
+ */
+ if (mac802154_set_header_security(sdata, &hdr, &cb) < 0)
+ return -EINVAL;
+
+ hdr.dest.pan_id = wpan_dev->pan_id;
+ hdr.dest.mode = IEEE802154_ADDR_LONG;
+ memcpy(&hdr.dest.extended_addr, daddr, IEEE802154_EXTENDED_ADDR_LEN);
+
+ hdr.source.pan_id = hdr.dest.pan_id;
+ hdr.source.mode = IEEE802154_ADDR_LONG;
+
+ if (!saddr)
+ hdr.source.extended_addr = wpan_dev->extended_addr;
+ else
+ memcpy(&hdr.source.extended_addr, saddr,
+ IEEE802154_EXTENDED_ADDR_LEN);
+
+ hlen = ieee802154_hdr_push(skb, &hdr);
+ if (hlen < 0)
+ return -EINVAL;
+
+ skb_reset_mac_header(skb);
+ skb->mac_len = hlen;
+
+ if (len > ieee802154_max_payload(&hdr))
+ return -EMSGSIZE;
+
+ return hlen;
+}
+
static int
mac802154_header_parse(const struct sk_buff *skb, unsigned char *haddr)
{
struct ieee802154_hdr hdr;
- struct ieee802154_addr *addr = (struct ieee802154_addr *)haddr;
if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0) {
pr_debug("malformed packet\n");
return 0;
}
- *addr = hdr.source;
- return sizeof(*addr);
+ if (hdr.source.mode == IEEE802154_ADDR_LONG) {
+ memcpy(haddr, &hdr.source.extended_addr,
+ IEEE802154_EXTENDED_ADDR_LEN);
+ return IEEE802154_EXTENDED_ADDR_LEN;
+ }
+
+ return 0;
}
-static struct header_ops mac802154_header_ops = {
- .create = mac802154_header_create,
- .parse = mac802154_header_parse,
+static const struct header_ops mac802154_header_ops = {
+ .create = mac802154_header_create,
+ .parse = mac802154_header_parse,
};
static const struct net_device_ops mac802154_wpan_ops = {
@@ -513,6 +579,7 @@
sdata->dev->netdev_ops = &mac802154_wpan_ops;
sdata->dev->ml_priv = &mac802154_mlme_wpan;
wpan_dev->promiscuous_mode = false;
+ wpan_dev->header_ops = &ieee802154_header_ops;
mutex_init(&sdata->sec_mtx);