[PATCH net-next 0/6] A step closer to RFC 6458 compliancy

@@ -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. */

@@ -97,6 +97,8 @@ 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.
  */

@@ -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;

@@ -131,6 +131,8 @@ struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
 
 void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
 	struct msghdr *);
+void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
+	struct msghdr *);
 __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event);
 
 /* Is this event type enabled? */

@@ -158,6 +158,27 @@ struct sctp_sndrcvinfo {
 };
 
 /*
+ *  5.3.5 SCTP Receive Information Structure (SCTP_RCVINFO)
+ *
+ *   This cmsghdr structure specifies SCTP options for sendmsg().
+ *
+ *   cmsg_level    cmsg_type      cmsg_data[]
+ *   ------------  ------------   -------------------
+ *   IPPROTO_SCTP  SCTP_RCVINFO   struct sctp_rcvinfo
+ *
+ */
+struct sctp_rcvinfo {
+	__u16 rcv_sid;
+	__u16 rcv_ssn;
+	__u16 rcv_flags;
+	__u32 rcv_ppid;
+	__u32 rcv_tsn;
+	__u32 rcv_cumtsn;
+	__u32 rcv_context;
+	sctp_assoc_t rcv_assoc_id;
+};
+
+/*
  *  sinfo_flags: 16 bits (unsigned integer)
  *
  *   This field may contain any of the following flags and is composed of

@@ -184,6 +205,8 @@ typedef enum sctp_cmsg_type {
 #define SCTP_INIT	SCTP_INIT
 	SCTP_SNDRCV,            /* 5.2.2 SCTP Header Information Structure */
 #define SCTP_SNDRCV	SCTP_SNDRCV
+	SCTP_RCVINFO,
+#define SCTP_RCVINFO SCTP_RCVINFO
 } sctp_cmsg_t;
 
 /*

@@ -2094,6 +2094,12 @@ static int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
 	}
 
+
+	/* Check if SCTP_RCVINFO should be included */
+	if(sp->recvrcvinfo){
+		sctp_ulpevent_read_rcvinfo(event, msg);
+	}
+
 	/* Check if we allow SCTP_SNDRCVINFO. */
 	if (sp->subscribe.sctp_data_io_event)
 		sctp_ulpevent_read_sndrcvinfo(event, msg);

@@ -900,6 +900,97 @@ __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
 	return notification->sn_header.sn_type;
 }
 
+void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
+		struct msghdr *msghdr)
+{
+	struct sctp_rcvinfo rinfo;
+
+	if (sctp_ulpevent_is_notification(event)){
+		return;
+	}
+
+	/* Sockets API Extensions for SCTP
+	 * Section 5.3.5 SCTP Receive Information Structure (SCTP_SNDRCV)
+	 *
+	 * rcv_sid: 16 bits (unsigned integer)
+	 *
+	 * The SCTP stack places the message's stream number in this
+	 * value.
+	 */
+	rinfo.rcv_sid = event->stream;
+
+	/* rcv_ssn: 16 bits (unsigned integer)
+	 * This value contains the stream sequence number that the
+	 * remote endpoint placed in the DATA chunk.  For fragmented
+	 * messages, this is the same number for all deliveries of the
+	 * message (if more than one recvmsg() is needed to read
+	 * the message)
+	 */
+	rinfo.rcv_ssn = event->ssn;
+
+
+	/* rcv_ppid: 32 bits (unsigned integer)
+	 *
+	 * This value is the same information that was passed by the
+	 * upper layer in the peer application.  Please note that the SCTP
+	 * stack performs no byte order modification of this field.
+	 * For example, if the DATA chunk has to contain a given
+	 * value in network byte order, the SCTP user has to perform the
+	 * ntohl() computation.
+	 */
+	rinfo.rcv_ppid = event->ppid;
+
+	/* rcv_flags: 16 bits (unsigned integer)
+	 *
+	 * This field may contain any of the following flags and is composed of
+	 * a bitwise OR of these values.
+	 *
+	 * recvmsg() flags:
+	 *
+	 * SCTP_UNORDERED - This flag is present when the message was sent
+	 *                 non-ordered.
+	 */
+
+	rinfo.rcv_flags = event->flags;
+
+	/* rcv_tsn: 32 bits (unsigned integer)
+	 *
+	 * This field holds a TSN that was assigned to one of the SCTP
+	 * DATA chunks.
+	 */
+	rinfo.rcv_tsn = event->tsn;
+
+	/* rcv_cumtsn: 32 bits (unsigned integer)
+	 *
+	 * This field will hold the current cumulative TSN as known
+	 * by the underlying SCTP layer.
+	 */
+	rinfo.rcv_cumtsn = event->cumtsn;
+
+	/* rcv_assoc_id: sizeof (sctp_assoc_t)
+	 *
+	 * The association handle field, sinfo_assoc_id, holds the identifier
+	 * for the association announced in the COMMUNICATION_UP notification.
+	 * All notifications for a given association have the same identifier.
+	 * Ignored for one-to-one style sockets.
+	 */
+	rinfo.rcv_assoc_id = sctp_assoc2id(event->asoc);
+
+	/* rcv_context: 32 bits (unsigned integer)
+	 *
+	 * This value is an opaque 32-bit context datum that was
+	 * set by the user with the SCTP_CONTEXT socket option.  This
+	 * value is passed back to the upper layer if an error occurs on
+	 * the send of a message and is retrieved with each undelivered
+	 * message.
+	 */
+	rinfo.rcv_context = event->asoc->default_rcv_context;
+
+	put_cmsg(msghdr, IPPROTO_SCTP, SCTP_RCVINFO,
+			sizeof(struct sctp_rcvinfo), (void *)&rinfo);
+}
+
+
 /* Copy out the sndrcvinfo into a msghdr.  */
 void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
 				   struct msghdr *msghdr)

@@ -1921,9 +1921,16 @@ struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
 /* A convenience structure to parse out SCTP specific CMSGs. */
 typedef struct sctp_cmsgs {
 	struct sctp_initmsg *init;
-	struct sctp_sndrcvinfo *info;
+	union {
+		struct sctp_sndrcvinfo *srinfo;
+		struct sctp_sndinfo *sinfo;
+	} info;
+	sctp_cmsg_t cmsg_type;
 } sctp_cmsgs_t;
 
+#define sr_info info.srinfo
+#define s_info info.sinfo
+
 /* Structure for tracking memory objects */
 typedef struct {
 	char *label;

@@ -156,6 +156,23 @@ struct sctp_sndrcvinfo {
 	__u32 sinfo_cumtsn;
 	sctp_assoc_t sinfo_assoc_id;
 };
+/*
+ * 5.3.4 SCTP Send Information Structure (SCTP_SNDINFO)
+ *
+ *   This cmsghdr structure specifies SCTP options for sendmsg().
+ *
+ *   cmsg_level    cmsg_type      cmsg_data[]
+ *   ------------  ------------   -------------------
+ *   IPPROTO_SCTP  SCTP_SNDINFO   struct sctp_sndinfo
+ *
+ */
+struct sctp_sndinfo {
+	__u16 snd_sid;
+	__u16 snd_flags;
+	__u32 snd_ppid;
+	__u32 snd_context;
+	sctp_assoc_t snd_assoc_id;
+};
 
 /*
  *  5.3.5 SCTP Receive Information Structure (SCTP_RCVINFO)

@@ -207,6 +224,8 @@ typedef enum sctp_cmsg_type {
 #define SCTP_SNDRCV	SCTP_SNDRCV
 	SCTP_RCVINFO,
 #define SCTP_RCVINFO SCTP_RCVINFO
+	SCTP_SNDINFO,
+#define SCTP_SNDINFO SCTP_SNDINFO
 } sctp_cmsg_t;
 
 /*

@@ -1648,10 +1648,21 @@ static int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
 		msg_name = msg->msg_name;
 	}
 
-	sinfo = cmsgs.info;
+	if(cmsgs.cmsg_type == SCTP_SNDINFO){
+		memset(&default_sinfo, 0, sizeof(default_sinfo));
+		default_sinfo.sinfo_flags = cmsgs.s_info->snd_flags;
+		default_sinfo.sinfo_stream = cmsgs.s_info->snd_sid;
+		default_sinfo.sinfo_assoc_id = cmsgs.s_info->snd_assoc_id;
+		default_sinfo.sinfo_ppid = cmsgs.s_info->snd_ppid;
+		default_sinfo.sinfo_context = cmsgs.s_info->snd_context;
+		sinfo = &default_sinfo;
+	}else{
+		sinfo = cmsgs.sr_info;
+	}
+
 	sinit = cmsgs.init;
 
-	/* Did the user specify SNDRCVINFO?  */
+	/* Did the user specify SNDINFO/SNDRCVINFO?  */
 	if (sinfo) {
 		sinfo_flags = sinfo->sinfo_flags;
 		associd = sinfo->sinfo_assoc_id;

@@ -1858,7 +1869,7 @@ static int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
 	pr_debug("%s: we have a valid association\n", __func__);
 
 	if (!sinfo) {
-		/* If the user didn't specify SNDRCVINFO, make up one with
+		/* If the user didn't specify SNDINFO/SNDRCVINFO, make up one with
 		 * some defaults.
 		 */
 		memset(&default_sinfo, 0, sizeof(default_sinfo));

@@ -1869,6 +1880,8 @@ static int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
 		sinfo = &default_sinfo;
+	}else{
+		sinfo->sinfo_timetolive = asoc->default_timetolive;
 	}
 
 	/* API 7.1.7, the sndbuf size per association bounds the

@@ -6473,16 +6486,46 @@ static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
 				return -EINVAL;
 
-			cmsgs->info =
+			cmsgs->info.srinfo =
 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
 
 			/* Minimally, validate the sinfo_flags. */
-			if (cmsgs->info->sinfo_flags &
+			if (cmsgs->sr_info->sinfo_flags &
 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
 			      SCTP_ABORT | SCTP_EOF))
 				return -EINVAL;
 			break;
 
+		case SCTP_SNDINFO:
+			/* SCTP Socket API Extension
+			 * 5.3.4 SCTP Send Information Structure (SCTP_SNDINFO)
+			 *
+			 * This cmsghdr structure specifies SCTP options for
+			 * sendmsg(). This structure and SCTP_RCVINFO replaces
+			 * SCTP_SNDRCV which has been depleted.
+			 *
+			 * cmsg_level    cmsg_type      cmsg_data[]
+			 * ------------  ------------   ---------------------
+			 * IPPROTO_SCTP  SCTP_SNDINFO    struct sctp_sndinfo
+			 * */
+			if(cmsg->cmsg_len !=
+					CMSG_LEN(sizeof(struct sctp_sndinfo))){
+
+				return -EINVAL;
+			}
+
+			/* SCTP_SENDALL should also be added here when
+			 * it is implemented */
+			cmsgs->info.sinfo = (struct sctp_sndinfo *)CMSG_DATA(cmsg);
+			cmsgs->cmsg_type = SCTP_SNDINFO;
+
+			if (cmsgs->s_info->snd_flags &
+					~(SCTP_UNORDERED | SCTP_ADDR_OVER |
+						SCTP_ABORT | SCTP_EOF)){
+				return -EINVAL;
+			}
+			break;
+
 		default:
 			return -EINVAL;
 		}

@@ -217,6 +217,7 @@ struct sctp_sock {
 	__u32 adaptation_ind;
 	__u32 pd_point;
 	__u8 recvrcvinfo;
+	__u8 recvnxtinfo;
 
 	atomic_t pd_mode;
 	/* Receive to here while partial delivery is in effect. */

@@ -98,6 +98,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_PEER_ADDR_THLDS	31
 
 #define SCTP_RECVRCVINFO 32
+#define SCTP_RECVNXTINFO 33
 
 /* Internal Socket Options. Some of the sctp library functions are
  * implemented using these socket options.

@@ -3602,6 +3602,20 @@ static int sctp_setsockopt_recvrcvinfo(struct sock *sk,
 }
 
 
+static int sctp_setsockopt_recvnxtinfo(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)->recvnxtinfo = (val == 0) ? 0 : 1;
+	return 0;
+}
 
 /* API 6.2 setsockopt(), getsockopt()
  *

@@ -3757,6 +3771,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_RECVRCVINFO:
 		retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen);
 		break;
+	case SCTP_RECVNXTINFO:
+		retval = sctp_setsockopt_recvnxtinfo(sk, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;

@@ -4006,6 +4023,9 @@ static int sctp_init_sock(struct sock *sk)
 	/* No SCTP_RECVRCVINFO by default. */
 	sp->recvrcvinfo = 0;
 
+	/* No SCTP_RECVNXTINFO by default. */
+	sp->recvnxtinfo = 0;
+
 	/* Enable by default. */
 	sp->v4mapped          = 1;
 

@@ -5777,6 +5797,26 @@ static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
 	return 0;
 }
 
+static int sctp_getsockopt_recvnxtinfo(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)->recvnxtinfo == 1);
+
+	if(put_user(len, optlen))
+		return -EFAULT;
+	if(copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
 static int sctp_getsockopt_recvrcvinfo(struct sock *sk,
 		int len,
 		char __user *optval,

@@ -5944,6 +5984,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname,
 	case SCTP_RECVRCVINFO:
 		retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
 		break;
+	case SCTP_RECVNXTINFO:
+		retval = sctp_getsockopt_recvnxtinfo(sk, len, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;

@@ -133,6 +133,8 @@ void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
 	struct msghdr *);
 void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
 	struct msghdr *);
+void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
+	struct msghdr *, struct sk_buff *);
 __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event);
 
 /* Is this event type enabled? */

@@ -2061,11 +2061,11 @@ static int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
 			struct msghdr *msg, size_t len, int noblock,
 			int flags, int *addr_len)
 {
-	struct sctp_ulpevent *event = NULL;
+	struct sctp_ulpevent *event = NULL, *nxt_event = NULL;
 	struct sctp_sock *sp = sctp_sk(sk);
-	struct sk_buff *skb;
+	struct sk_buff *skb, *nxtskb = NULL;
 	int copied;
-	int err = 0;
+	int err = 0, err2 = 0;
 	int skb_len;
 
 	pr_debug("%s: sk:%p, msghdr:%p, len:%zd, noblock:%d, flags:0x%x, "

@@ -2113,6 +2113,14 @@ static int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
 		sctp_ulpevent_read_rcvinfo(event, msg);
 	}
 
+	if(sp->recvnxtinfo){
+		nxtskb = sctp_skb_recv_datagram(sk, MSG_PEEK, 1, &err2);
+		if(nxtskb && nxtskb->len){
+			nxt_event = sctp_skb2event(nxtskb);
+			sctp_ulpevent_read_nxtinfo(nxt_event, msg, nxtskb);
+		}
+	}
+
 	/* Check if we allow SCTP_SNDRCVINFO. */
 	if (sp->subscribe.sctp_data_io_event)
 		sctp_ulpevent_read_sndrcvinfo(event, msg);

@@ -2162,6 +2170,8 @@ out_free:
 		sctp_ulpevent_free(event);
 	}
 out:
+	if(nxtskb)
+		kfree_skb(nxtskb);
 	sctp_release_sock(sk);
 	return err;
 }

@@ -900,6 +900,73 @@ __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
 	return notification->sn_header.sn_type;
 }
 
+void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
+		struct msghdr *msghdr, struct sk_buff* skb)
+{
+	struct sctp_nxtinfo nxtinfo;
+
+
+	/* Sockets API Extensions for SCTP
+	 * Section 5.3.6 SCTP Next Receive Information Structure (SCTP_NXTINFO)
+	 *
+	 * nxt_sid: 16 bits (unsigned integer)
+	 *
+	 * The SCTP stack places the next message's stream number in
+	 * this value.
+	 */
+	nxtinfo.nxt_sid = event->stream;
+
+	/* nxt_ppid: 32 bits (unsigned integer)
+	 *
+	 * This value is the same information that was passed by the
+	 * upper layer in the peer application for the next message.  Please
+	 * note  that the SCTP stack performs no byte order modification of
+	 * this field.  For example, if the DATA chunk has to contain a given
+	 * value in network byte order, the SCTP user has to perform the
+	 * ntohl() computation.
+	 */
+	nxtinfo.nxt_ppid = event->ppid;
+
+	/* nxt_flags: 16 bits (unsigned integer)
+	 *
+	 * This field may contain any of the following flags and is
+	 * composed of a bitwise OR of these values.
+	 */
+	nxtinfo.nxt_flags = event->flags;
+
+	/*
+	 * SCTP_NOTIFICATION is not set in Linux yet.
+	 *
+	 * if (sctp_ulpevent_is_notification(event)){
+	 *     nxtinfo.nxt_flags |= SCTP_NOTIFICATION;
+	 * }
+	 *
+	 */
+
+	/* nxt_length: 32 bits (unsigned integer)
+	 *
+	 * This value is the length of the message currently within
+	 * the socket buffer.  This might NOT be the entire length of the
+	 * message, since a partial delivery may be in progress.  Only if the
+	 * flag SCTP_COMPLETE is set in the nxt_flags field does this field
+	 * represent the size of the entire next message.
+	 */
+	nxtinfo.nxt_length = skb->len;
+
+	/* nxt_assoc_id: sizeof(sctp_assoc_t)
+	 * The association handle field of the next message,
+	 * nxt_assoc_id, holds the identifier for the association
+	 * announced in the SCTP_COMM_UP notification.  All
+	 * notifications for a given association have the same
+	 * identifier.  This field is ignored for one-to-one style
+	 * sockets.
+	 */
+	nxtinfo.nxt_assoc_id = sctp_assoc2id(event->asoc);
+
+	put_cmsg(msghdr, IPPROTO_SCTP, SCTP_NXTINFO,
+			sizeof(struct sctp_nxtinfo), (void *)&nxtinfo);
+}
+
 void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
 		struct msghdr *msghdr)
 {

@@ -99,6 +99,7 @@ typedef __s32 sctp_assoc_t;
 
 #define SCTP_RECVRCVINFO 32
 #define SCTP_RECVNXTINFO 33
+#define SCTP_DEFAULT_SNDINFO 34
 
 /* Internal Socket Options. Some of the sctp library functions are
  * implemented using these socket options.

@@ -2801,6 +2801,55 @@ static int sctp_setsockopt_default_send_param(struct sock *sk,
 
 	return 0;
 }
+/*
+ * 8.1.31. Set Default Send Parameters (SCTP_DEFAULT_SNDINFO)
+ *
+ *   Applications that wish to use the sendto() system call may wish to
+ *   specify a default set of parameters that would normally be supplied
+ *   through the inclusion of ancillary data.  This socket option allows
+ *   such an application to set the default sctp_sndinfo structure.  The
+ *   application that wishes to use this socket option simply passes the
+ *   sctp_sndinfo structure (defined in Section 5.3.4) to this call.  The
+ *   input parameters accepted by this call include snd_sid, snd_flags,
+ *   snd_ppid, and snd_context.  The snd_flags parameter is composed of a
+ *   bitwise OR of SCTP_UNORDERED, SCTP_EOF, and SCTP_SENDALL.  The
+ *   snd_assoc_id field specifies the association to which to apply the
+ *   parameters.  For a one-to-many style socket, any of the predefined
+ *   constants are also allowed in this field.  The field is ignored for
+ *   one-to-one style sockets.
+ */
+static int sctp_setsockopt_default_sndinfo(struct sock *sk,
+		char __user *optval,
+		unsigned int optlen){
+	struct sctp_sndinfo info;
+	struct sctp_association *asoc;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (optlen != sizeof(struct sctp_sndinfo))
+		return -EINVAL;
+	if (copy_from_user(&info, optval, optlen))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
+	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* Note! asoc->default_timetolive is not set in this way anymore.
+	 * The PR-SCTP extension needs to be implemented.  */
+	if (asoc) {
+		asoc->default_stream = info.snd_sid;
+		asoc->default_flags = info.snd_flags;
+		asoc->default_ppid = info.snd_ppid;
+		asoc->default_context = info.snd_context;
+	} else {
+		sp->default_stream = info.snd_sid;
+		sp->default_flags = info.snd_flags;
+		sp->default_ppid = info.snd_ppid;
+		sp->default_context = info.snd_context;
+	}
+	return 0;
+}
+
 
 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
  *

@@ -3724,6 +3773,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 		retval = sctp_setsockopt_default_send_param(sk, optval,
 							    optlen);
 		break;
+	case SCTP_DEFAULT_SNDINFO:
+		retval = sctp_setsockopt_default_sndinfo(sk, optval, optlen);
+		break;
 	case SCTP_PRIMARY_ADDR:
 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
 		break;

@@ -5063,6 +5115,45 @@ static int sctp_getsockopt_default_send_param(struct sock *sk,
 
 	return 0;
 }
+static int sctp_getsockopt_default_sndinfo(struct sock *sk,
+		int len, char __user *optval,
+		int __user *optlen)
+{
+	struct sctp_sndinfo info;
+	struct sctp_association *asoc;
+	struct sctp_sock *sp = sctp_sk(sk);
+
+	if (len < sizeof(struct sctp_sndinfo))
+		return -EINVAL;
+
+	len = sizeof(struct sctp_sndinfo);
+
+	if (copy_from_user(&info, optval, len))
+		return -EFAULT;
+
+	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
+	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
+		return -EINVAL;
+
+	if (asoc) {
+		info.snd_sid = asoc->default_stream;
+		info.snd_flags = asoc->default_flags;
+		info.snd_ppid = asoc->default_ppid;
+		info.snd_context = asoc->default_context;
+	} else {
+		info.snd_sid = sp->default_stream;
+		info.snd_flags = sp->default_flags;
+		info.snd_ppid = sp->default_ppid;
+		info.snd_context = sp->default_context;
+	}
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &info, len))
+		return -EFAULT;
+
+	return 0;
+}
 
 /*
  *

@@ -5917,6 +6008,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname,
 		retval = sctp_getsockopt_default_send_param(sk, len,
 							    optval, optlen);
 		break;
+	case SCTP_DEFAULT_SNDINFO:
+		retval = sctp_getsockopt_default_sndinfo(sk, len, optval, optlen);
+		break;
 	case SCTP_PRIMARY_ADDR:
 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
 		break;