Phonet: set the pipe handle using setsockopt

This provides flexibility to set the pipe handle
using setsockopt. The pipe can be enabled (if disabled) later
using ioctl.

Signed-off-by: Hemant Ramdasi <[e-mail]>
Signed-off-by: Dinesh Kumar Sharma <[e-mail]>
Acked-by: Rémi Denis-Courmont <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/linux/phonet.h

···
 #define PNPIPE_ENCAP		1
 #define PNPIPE_IFINDEX		2
 #define PNPIPE_HANDLE		3
+#define PNPIPE_INITSTATE	4
 
 #define PNADDR_ANY		0
 #define PNADDR_BROADCAST	0xFC
···
 
 /* ioctls */
 #define SIOCPNGETOBJECT		(SIOCPROTOPRIVATE + 0)
+#define SIOCPNENABLEPIPE	(SIOCPROTOPRIVATE + 13)
 #define SIOCPNADDRESOURCE	(SIOCPROTOPRIVATE + 14)
 #define SIOCPNDELRESOURCE	(SIOCPROTOPRIVATE + 15)
 

net/phonet/pep.c

···
 	return pipe_handler_send_created_ind(sk);
 }
 
+static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb)
+{
+	struct pnpipehdr *hdr = pnp_hdr(skb);
+
+	if (hdr->error_code != PN_PIPE_NO_ERROR)
+		return -ECONNREFUSED;
+
+	return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */,
+		NULL, 0, GFP_ATOMIC);
+
+}
+
+static void pipe_start_flow_control(struct sock *sk)
+{
+	struct pep_sock *pn = pep_sk(sk);
+
+	if (!pn_flow_safe(pn->tx_fc)) {
+		atomic_set(&pn->tx_credits, 1);
+		sk->sk_write_space(sk);
+	}
+	pipe_grant_credits(sk, GFP_ATOMIC);
+}
+
 /* Queue an skb to an actively connected sock.
  * Socket lock must be held. */
 static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb)
···
 			sk->sk_state = TCP_CLOSE_WAIT;
 			break;
 		}
+		if (pn->init_enable == PN_PIPE_DISABLE)
+			sk->sk_state = TCP_SYN_RECV;
+		else {
+			sk->sk_state = TCP_ESTABLISHED;
+			pipe_start_flow_control(sk);
+		}
+		break;
+
+	case PNS_PEP_ENABLE_RESP:
+		if (sk->sk_state != TCP_SYN_SENT)
+			break;
+
+		if (pep_enableresp_rcv(sk, skb)) {
+			sk->sk_state = TCP_CLOSE_WAIT;
+			break;
+		}
 
 		sk->sk_state = TCP_ESTABLISHED;
-		if (!pn_flow_safe(pn->tx_fc)) {
-			atomic_set(&pn->tx_credits, 1);
-			sk->sk_write_space(sk);
-		}
-		pipe_grant_credits(sk, GFP_ATOMIC);
+		pipe_start_flow_control(sk);
 		break;
 
 	case PNS_PEP_DISCONNECT_RESP:
···
 	int err;
 	u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD };
 
-	pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
+	if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE)
+		pn->pipe_handle = 1; /* anything but INVALID_HANDLE */
+
 	err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ,
-					PN_PIPE_ENABLE, data, 4);
+				pn->init_enable, data, 4);
 	if (err) {
 		pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
 		return err;
 	}
+
 	sk->sk_state = TCP_SYN_SENT;
+
+	return 0;
+}
+
+static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len)
+{
+	int err;
+
+	err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD,
+				NULL, 0);
+	if (err)
+		return err;
+
+	sk->sk_state = TCP_SYN_SENT;
+
 	return 0;
 }
 
···
 {
 	struct pep_sock *pn = pep_sk(sk);
 	int answ;
+	int ret = -ENOIOCTLCMD;
 
 	switch (cmd) {
 	case SIOCINQ:
-		if (sk->sk_state == TCP_LISTEN)
-			return -EINVAL;
+		if (sk->sk_state == TCP_LISTEN) {
+			ret = -EINVAL;
+			break;
+		}
 
 		lock_sock(sk);
 		if (sock_flag(sk, SOCK_URGINLINE) &&
···
 		else
 			answ = 0;
 		release_sock(sk);
-		return put_user(answ, (int __user *)arg);
+		ret = put_user(answ, (int __user *)arg);
+		break;
+
+	case SIOCPNENABLEPIPE:
+		lock_sock(sk);
+		if (sk->sk_state == TCP_SYN_SENT)
+			ret =  -EBUSY;
+		else if (sk->sk_state == TCP_ESTABLISHED)
+			ret = -EISCONN;
+		else
+			ret = pep_sock_enable(sk, NULL, 0);
+		release_sock(sk);
+		break;
 	}
 
-	return -ENOIOCTLCMD;
+	return ret;
 }
 
 static int pep_init(struct sock *sk)
···
 		}
 		goto out_norel;
 
+	case PNPIPE_HANDLE:
+		if ((sk->sk_state == TCP_CLOSE) &&
+			(val >= 0) && (val < PN_PIPE_INVALID_HANDLE))
+			pn->pipe_handle = val;
+		else
+			err = -EINVAL;
+		break;
+
+	case PNPIPE_INITSTATE:
+		pn->init_enable = !!val;
+		break;
+
 	default:
 		err = -ENOPROTOOPT;
 	}
···
 		val = pn->pipe_handle;
 		if (val == PN_PIPE_INVALID_HANDLE)
 			return -EINVAL;
+		break;
+
+	case PNPIPE_INITSTATE:
+		val = pn->init_enable;
 		break;
 
 	default: