Merge branch 'ieee802154-next'

Phoebe Buckheister says:

====================
802154: some cleanups and fixes

This series adds some definitions for 802.15.4 header fields that were missing,
changes 6lowpan fragmentation to be aware of security headers and fixes
802.15.4 datagram socket sendmsg(), which was entirely incompliant to date.
Also a few minor changes to mac_cb handling, mark a single-use function static,
and correctly check for EMSGSIZE conditions during wpan_header_create.

Changes since v1:
  * rename mac_cb_alloc to mac_cb_init
  * catch all error cases of sendmsg() instead of only !conn && msg_name
  * redo 6lowpan fragmentation to not clone lower layer headers
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 45 insertions, 7 deletions

diff --git a/net/ieee802154/header_ops.c b/net/ieee802154/header_ops.c
index bed42a48408c..c09294e39ca6 100644
--- a/net/ieee802154/header_ops.c
+++ b/net/ieee802154/header_ops.c
@@ -195,15 +195,16 @@ ieee802154_hdr_get_sechdr(const u8 *buf, struct ieee802154_sechdr *hdr)
 	return pos;
 }
 
+static int ieee802154_sechdr_lengths[4] = {
+	[IEEE802154_SCF_KEY_IMPLICIT] = 5,
+	[IEEE802154_SCF_KEY_INDEX] = 6,
+	[IEEE802154_SCF_KEY_SHORT_INDEX] = 10,
+	[IEEE802154_SCF_KEY_HW_INDEX] = 14,
+};
+
 static int ieee802154_hdr_sechdr_len(u8 sc)
 {
-	switch (IEEE802154_SCF_KEY_ID_MODE(sc)) {
-	case IEEE802154_SCF_KEY_IMPLICIT: return 5;
-	case IEEE802154_SCF_KEY_INDEX: return 6;
-	case IEEE802154_SCF_KEY_SHORT_INDEX: return 10;
-	case IEEE802154_SCF_KEY_HW_INDEX: return 14;
-	default: return -EINVAL;
-	}
+	return ieee802154_sechdr_lengths[IEEE802154_SCF_KEY_ID_MODE(sc)];
 }
 
 static int ieee802154_hdr_minlen(const struct ieee802154_hdr *hdr)
@@ -285,3 +286,40 @@ ieee802154_hdr_peek_addrs(const struct sk_buff *skb, struct ieee802154_hdr *hdr)
 	return pos;
 }
 EXPORT_SYMBOL_GPL(ieee802154_hdr_peek_addrs);
+
+int
+ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr)
+{
+	const u8 *buf = skb_mac_header(skb);
+	int pos;
+
+	pos = ieee802154_hdr_peek_addrs(skb, hdr);
+	if (pos < 0)
+		return -EINVAL;
+
+	if (hdr->fc.security_enabled) {
+		u8 key_id_mode = IEEE802154_SCF_KEY_ID_MODE(*(buf + pos));
+		int want = pos + ieee802154_sechdr_lengths[key_id_mode];
+
+		if (buf + want > skb_tail_pointer(skb))
+			return -EINVAL;
+
+		pos += ieee802154_hdr_get_sechdr(buf + pos, &hdr->sec);
+	}
+
+	return pos;
+}
+EXPORT_SYMBOL_GPL(ieee802154_hdr_peek);
+
+int ieee802154_max_payload(const struct ieee802154_hdr *hdr)
+{
+	int hlen = ieee802154_hdr_minlen(hdr);
+
+	if (hdr->fc.security_enabled) {
+		hlen += ieee802154_sechdr_lengths[hdr->sec.key_id_mode] - 1;
+		hlen += ieee802154_sechdr_authtag_len(&hdr->sec);
+	}
+
+	return IEEE802154_MTU - hlen - IEEE802154_MFR_SIZE;
+}
+EXPORT_SYMBOL_GPL(ieee802154_max_payload);