ieee802154: fix dgram socket sendmsg()

802.15.4 datagram sockets do not currently have a compliant sendmsg().
The destination address supplied is always ignored, and in unconnected
mode, packets are broadcast instead of dropped with -EDESTADDRREQ. This
patch fixes 802.15.4 dgram sockets to be compliant, i.e.

 !conn && !msg_name => -EDESTADDRREQ
 !conn &&  msg_name => send to msg_name
  conn && !msg_name => send to connected
  conn &&  msg_name => -EISCONN

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 9 deletions

diff --git a/net/ieee802154/dgram.c b/net/ieee802154/dgram.c
index d95e2e1bdf54..76c77256a56e 100644
--- a/net/ieee802154/dgram.c
+++ b/net/ieee802154/dgram.c
@@ -45,6 +45,7 @@ struct dgram_sock {
         struct ieee802154_addr dst_addr;
 
         unsigned int bound:1;
+        unsigned int connected:1;
         unsigned int want_ack:1;
 };
 
@@ -73,10 +74,7 @@ static int dgram_init(struct sock *sk)
 {
         struct dgram_sock *ro = dgram_sk(sk);
 
-        ro->dst_addr.mode = IEEE802154_ADDR_LONG;
-        ro->dst_addr.pan_id = cpu_to_le16(IEEE802154_PANID_BROADCAST);
         ro->want_ack = 1;
-        memset(&ro->dst_addr.extended_addr, 0xff, IEEE802154_ADDR_LEN);
         return 0;
 }
 
@@ -183,6 +181,7 @@ static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
         }
 
         ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
+        ro->connected = 1;
 
 out:
         release_sock(sk);
@@ -194,10 +193,7 @@ static int dgram_disconnect(struct sock *sk, int flags)
         struct dgram_sock *ro = dgram_sk(sk);
 
         lock_sock(sk);
-
-        ro->dst_addr.mode = IEEE802154_ADDR_LONG;
-        memset(&ro->dst_addr.extended_addr, 0xff, IEEE802154_ADDR_LEN);
-
+        ro->connected = 0;
         release_sock(sk);
 
         return 0;
@@ -211,6 +207,7 @@ static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
         struct sk_buff *skb;
         struct ieee802154_mac_cb *cb;
         struct dgram_sock *ro = dgram_sk(sk);
+        struct ieee802154_addr dst_addr;
         int hlen, tlen;
         int err;
 
@@ -219,6 +216,11 @@ static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
                 return -EOPNOTSUPP;
         }
 
+        if (!ro->connected && !msg->msg_name)
+                return -EDESTADDRREQ;
+        else if (ro->connected && msg->msg_name)
+                return -EISCONN;
+
         if (!ro->bound)
                 dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
         else
@@ -254,8 +256,16 @@ static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
         cb->type = IEEE802154_FC_TYPE_DATA;
         cb->ackreq = ro->want_ack;
 
-        err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
-                        ro->bound ? &ro->src_addr : NULL, size);
+        if (msg->msg_name) {
+                DECLARE_SOCKADDR(struct sockaddr_ieee802154*, daddr, msg->msg_name);
+
+                ieee802154_addr_from_sa(&dst_addr, &daddr->addr);
+        } else {
+                dst_addr = ro->dst_addr;
+        }
+
+        err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &dst_addr,
+                              ro->bound ? &ro->src_addr : NULL, size);
         if (err < 0)
                 goto out_skb;