[PATCH net-next 1/6] Support for SCTP_RECVRCVINFO socket option

[Geir Ola Vaagland <geirola@gmail.com>]

CC: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Geir Ola Vaagland <geirola@gmail.com>
---
 include/net/sctp/structs.h |  1 +
 include/uapi/linux/sctp.h  |  2 ++
 net/sctp/socket.c          | 48 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 0a248b3..75c598a 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -216,6 +216,7 @@ struct sctp_sock {
 	__u8 frag_interleave;
 	__u32 adaptation_ind;
 	__u32 pd_point;
+	__u8 recvrcvinfo;
 
 	atomic_t pd_mode;
 	/* Receive to here while partial delivery is in effect. */
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index ca451e9..a7db3b3 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -97,5 +97,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_AUTO_ASCONF       30
 #define SCTP_PEER_ADDR_THLDS	31
+#define SCTP_RECVRCVINFO 32
+
 /* Internal Socket Options. Some of the sctp library functions are
  * implemented using these socket options.
  */
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 146b35d..1f3281b 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3566,6 +3566,24 @@ static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
 	return 0;
 }
 
+static int sctp_setsockopt_recvrcvinfo(struct sock *sk,
+					char __user *optval,
+					unsigned int optlen){
+
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (get_user(val, (int __user *)optval))
+		return -EFAULT;
+
+	sctp_sk(sk)->recvrcvinfo = (val == 0) ? 0 : 1;
+	return 0;
+}
+
+
+
 /* API 6.2 setsockopt(), getsockopt()
  *
  * Applications use setsockopt() and getsockopt() to set or retrieve
@@ -3717,6 +3735,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_PEER_ADDR_THLDS:
 		retval = sctp_setsockopt_paddr_thresholds(sk, optval, optlen);
 		break;
+	case SCTP_RECVRCVINFO:
+		retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
@@ -3963,6 +3984,9 @@ static int sctp_init_sock(struct sock *sk)
 	/* Enable Nagle algorithm by default.  */
 	sp->nodelay           = 0;
 
+	/* No SCTP_RECVRCVINFO by default. */
+	sp->recvrcvinfo = 0;
+
 	/* Enable by default. */
 	sp->v4mapped          = 1;
 
@@ -5734,6 +5758,27 @@ static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
 	return 0;
 }
 
+static int sctp_getsockopt_recvrcvinfo(struct sock *sk,
+					int len,
+					char __user *optval,
+					int __user *optlen){
+
+	int val;
+
+	if (len < sizeof(int))
+		return -EINVAL;
+
+	len = sizeof(int);
+	val = (sctp_sk(sk)->recvrcvinfo == 1);
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+	return 0;
+}
+
+
+
 static int sctp_getsockopt(struct sock *sk, int level, int optname,
 			   char __user *optval, int __user *optlen)
 {
@@ -5877,6 +5922,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname,
 	case SCTP_GET_ASSOC_STATS:
 		retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
 		break;
+	case SCTP_RECVRCVINFO:
+		retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;