af_ieee802154: add support for WANT_ACK socket option

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/dgram.c b/net/ieee802154/dgram.c
index 25018a9..77ae685 100644
--- a/net/ieee802154/dgram.c
+++ b/net/ieee802154/dgram.c
@@ -44,6 +44,7 @@
 	struct ieee802154_addr dst_addr;
 
 	unsigned bound:1;
+	unsigned want_ack:1;
 };
 
 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
@@ -51,7 +52,6 @@
 	return container_of(sk, struct dgram_sock, sk);
 }
 
-
 static void dgram_hash(struct sock *sk)
 {
 	write_lock_bh(&dgram_lock);
@@ -74,6 +74,7 @@
 
 	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
 	ro->dst_addr.pan_id = 0xffff;
+	ro->want_ack = 1;
 	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
 	return 0;
 }
@@ -237,7 +238,10 @@
 
 	skb_reset_network_header(skb);
 
-	mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA | MAC_CB_FLAG_ACKREQ;
+	mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
+	if (ro->want_ack)
+		mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
+
 	mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 	err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
 			ro->bound ? &ro->src_addr : NULL, size);
@@ -382,13 +386,59 @@
 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 		    char __user *optval, int __user *optlen)
 {
-	return -EOPNOTSUPP;
+	struct dgram_sock *ro = dgram_sk(sk);
+
+	int val, len;
+
+	if (level != SOL_IEEE802154)
+		return -EOPNOTSUPP;
+
+	if (get_user(len, optlen))
+		return -EFAULT;
+
+	len = min_t(unsigned int, len, sizeof(int));
+
+	switch (optname) {
+	case WPAN_WANTACK:
+		val = ro->want_ack;
+		break;
+	default:
+		return -ENOPROTOOPT;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+	return 0;
 }
 
 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 		    char __user *optval, int __user optlen)
 {
-	return -EOPNOTSUPP;
+	struct dgram_sock *ro = dgram_sk(sk);
+	int val;
+	int err = 0;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	lock_sock(sk);
+
+	switch (optname) {
+	case WPAN_WANTACK:
+		ro->want_ack = !!val;
+		break;
+	default:
+		err = -ENOPROTOOPT;
+		break;
+	}
+
+	release_sock(sk);
+	return err;
 }
 
 struct proto ieee802154_dgram_prot = {