sctp: add SCTP_FUTURE_ASSOC for SCTP_PEER_ADDR_THLDS sockopt

Check with SCTP_FUTURE_ASSOC instead in
sctp_set/getsockopt_paddr_thresholds, it's compatible with 0.

It also adds pf_retrans in sctp_sock to support SCTP_FUTURE_ASSOC.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/sctp/structs.h

@@ -199,6 +199,8 @@ struct sctp_sock {
 	__u32 flowlabel;
 	__u8  dscp;
 
+	int pf_retrans;
+
 	/* The initial Path MTU to use for new associations. */
 	__u32 pathmtu;
 

net/sctp/associola.c

@@ -101,7 +101,7 @@ static struct sctp_association *sctp_association_init(
 	 * socket values.
 	 */
 	asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
-	asoc->pf_retrans  = net->sctp.pf_retrans;
+	asoc->pf_retrans  = sp->pf_retrans;
 
 	asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
 	asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);

net/sctp/socket.c

@@ -3888,11 +3888,25 @@ static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
 			   sizeof(struct sctp_paddrthlds)))
 		return -EFAULT;
 
-
-	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
-		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
-		if (!asoc)
+	if (!sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
+		trans = sctp_addr_id2transport(sk, &val.spt_address,
+					       val.spt_assoc_id);
+		if (!trans)
 			return -ENOENT;
+
+		if (val.spt_pathmaxrxt)
+			trans->pathmaxrxt = val.spt_pathmaxrxt;
+		trans->pf_retrans = val.spt_pathpfthld;
+
+		return 0;
+	}
+
+	asoc = sctp_id2assoc(sk, val.spt_assoc_id);
+	if (!asoc && val.spt_assoc_id != SCTP_FUTURE_ASSOC &&
+	    sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc) {
 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
 				    transports) {
 			if (val.spt_pathmaxrxt)
@@ -3904,14 +3918,11 @@ static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
 			asoc->pathmaxrxt = val.spt_pathmaxrxt;
 		asoc->pf_retrans = val.spt_pathpfthld;
 	} else {
-		trans = sctp_addr_id2transport(sk, &val.spt_address,
-					       val.spt_assoc_id);
-		if (!trans)
-			return -ENOENT;
+		struct sctp_sock *sp = sctp_sk(sk);
 
 		if (val.spt_pathmaxrxt)
-			trans->pathmaxrxt = val.spt_pathmaxrxt;
-		trans->pf_retrans = val.spt_pathpfthld;
+			sp->pathmaxrxt = val.spt_pathmaxrxt;
+		sp->pf_retrans = val.spt_pathpfthld;
 	}
 
 	return 0;
@@ -4781,6 +4792,7 @@ static int sctp_init_sock(struct sock *sk)
 	 */
 	sp->hbinterval  = net->sctp.hb_interval;
 	sp->pathmaxrxt  = net->sctp.max_retrans_path;
+	sp->pf_retrans  = net->sctp.pf_retrans;
 	sp->pathmtu     = 0; /* allow default discovery */
 	sp->sackdelay   = net->sctp.sack_timeout;
 	sp->sackfreq	= 2;
@@ -6917,14 +6929,7 @@ static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
 	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval, len))
 		return -EFAULT;
 
-	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
-		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
-		if (!asoc)
-			return -ENOENT;
-
-		val.spt_pathpfthld = asoc->pf_retrans;
-		val.spt_pathmaxrxt = asoc->pathmaxrxt;
-	} else {
+	if (!sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
 		trans = sctp_addr_id2transport(sk, &val.spt_address,
 					       val.spt_assoc_id);
 		if (!trans)
@@ -6932,6 +6937,23 @@ static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
 
 		val.spt_pathmaxrxt = trans->pathmaxrxt;
 		val.spt_pathpfthld = trans->pf_retrans;
+
+		return 0;
+	}
+
+	asoc = sctp_id2assoc(sk, val.spt_assoc_id);
+	if (!asoc && val.spt_assoc_id != SCTP_FUTURE_ASSOC &&
+	    sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc) {
+		val.spt_pathpfthld = asoc->pf_retrans;
+		val.spt_pathmaxrxt = asoc->pathmaxrxt;
+	} else {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		val.spt_pathpfthld = sp->pf_retrans;
+		val.spt_pathmaxrxt = sp->pathmaxrxt;
 	}
 
 	if (put_user(len, optlen) || copy_to_user(optval, &val, len))