socket.c

		return 0;
	}
	len -= skb_len;
	__skb_pull(skb, skb_len);

	skb_walk_frags(skb, list) {
		rlen = sctp_skb_pull(list, len);
		skb->len -= (len-rlen);
		skb->data_len -= (len-rlen);

		if (!rlen)
			return 0;

		len = rlen;
	}

	return len;
}

/* API 3.1.3  recvmsg() - UDP Style Syntax
 *
 *  ssize_t recvmsg(int socket, struct msghdr *message,
 *                    int flags);
 *
 *  socket  - the socket descriptor of the endpoint.
 *  message - pointer to the msghdr structure which contains a single
 *            user message and possibly some ancillary data.
 *
 *            See Section 5 for complete description of the data
 *            structures.
 *
 *  flags   - flags sent or received with the user message, see Section
 *            5 for complete description of the flags.
 */
static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);

SCTP_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_sock *sp = sctp_sk(sk);
	struct sk_buff *skb;
	int copied;
	int err = 0;
	int skb_len;

	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
			  "len", len, "knoblauch", noblock,
			  "flags", flags, "addr_len", addr_len);

	sctp_lock_sock(sk);

	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
		err = -ENOTCONN;
		goto out;
	}

	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
		goto out;

	/* Get the total length of the skb including any skb's in the
	 * frag_list.
	 */
	skb_len = skb->len;

	copied = skb_len;
	if (copied > len)
		copied = len;

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);

	event = sctp_skb2event(skb);

	if (err)
		goto out_free;

	sock_recv_ts_and_drops(msg, sk, skb);
	if (sctp_ulpevent_is_notification(event)) {
		msg->msg_flags |= MSG_NOTIFICATION;
		sp->pf->event_msgname(event, msg->msg_name, addr_len);
	} else {
		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
	}

	/* Check if we allow SCTP_SNDRCVINFO. */
	if (sp->subscribe.sctp_data_io_event)
		sctp_ulpevent_read_sndrcvinfo(event, msg);
#if 0
	/* FIXME: we should be calling IP/IPv6 layers.  */
	if (sk->sk_protinfo.af_inet.cmsg_flags)
		ip_cmsg_recv(msg, skb);
#endif

	err = copied;

	/* If skb's length exceeds the user's buffer, update the skb and
	 * push it back to the receive_queue so that the next call to
	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
	 */
	if (skb_len > copied) {
		msg->msg_flags &= ~MSG_EOR;
		if (flags & MSG_PEEK)
			goto out_free;
		sctp_skb_pull(skb, copied);
		skb_queue_head(&sk->sk_receive_queue, skb);

		/* When only partial message is copied to the user, increase
		 * rwnd by that amount. If all the data in the skb is read,
		 * rwnd is updated when the event is freed.
		 */
		if (!sctp_ulpevent_is_notification(event))
			sctp_assoc_rwnd_increase(event->asoc, copied);
		goto out;
	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
		   (event->msg_flags & MSG_EOR))
		msg->msg_flags |= MSG_EOR;
	else
		msg->msg_flags &= ~MSG_EOR;

out_free:
	if (flags & MSG_PEEK) {
		/* Release the skb reference acquired after peeking the skb in
		 * sctp_skb_recv_datagram().
		 */
		kfree_skb(skb);
	} else {
		/* Free the event which includes releasing the reference to
		 * the owner of the skb, freeing the skb and updating the
		 * rwnd.
		 */
		sctp_ulpevent_free(event);
	}
out:
	sctp_release_sock(sk);
	return err;
}

/* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
 *
 * This option is a on/off flag.  If enabled no SCTP message
 * fragmentation will be performed.  Instead if a message being sent
 * exceeds the current PMTU size, the message will NOT be sent and
 * instead a error will be indicated to the user.
 */
static int sctp_setsockopt_disable_fragments(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)->disable_fragments = (val == 0) ? 0 : 1;

	return 0;
}

static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
				  unsigned int optlen)
{
	struct sctp_association *asoc;
	struct sctp_ulpevent *event;

	if (optlen > sizeof(struct sctp_event_subscribe))
		return -EINVAL;
	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
		return -EFAULT;

	/*
	 * At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
	 * if there is no data to be sent or retransmit, the stack will
	 * immediately send up this notification.
	 */
	if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
				       &sctp_sk(sk)->subscribe)) {
		asoc = sctp_id2assoc(sk, 0);

		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
			event = sctp_ulpevent_make_sender_dry_event(asoc,
					GFP_ATOMIC);
			if (!event)
				return -ENOMEM;

			sctp_ulpq_tail_event(&asoc->ulpq, event);
		}
	}

	return 0;
}

/* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
 *
 * This socket option is applicable to the UDP-style socket only.  When
 * set it will cause associations that are idle for more than the
 * specified number of seconds to automatically close.  An association
 * being idle is defined an association that has NOT sent or received
 * user data.  The special value of '0' indicates that no automatic
 * close of any associations should be performed.  The option expects an
 * integer defining the number of seconds of idle time before an
 * association is closed.
 */
static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
				     unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);

	/* Applicable to UDP-style socket only */
	if (sctp_style(sk, TCP))
		return -EOPNOTSUPP;
	if (optlen != sizeof(int))
		return -EINVAL;
	if (copy_from_user(&sp->autoclose, optval, optlen))
		return -EFAULT;

	return 0;
}

/* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
 *
 * Applications can enable or disable heartbeats for any peer address of
 * an association, modify an address's heartbeat interval, force a
 * heartbeat to be sent immediately, and adjust the address's maximum
 * number of retransmissions sent before an address is considered
 * unreachable.  The following structure is used to access and modify an
 * address's parameters:
 *
 *  struct sctp_paddrparams {
 *     sctp_assoc_t            spp_assoc_id;
 *     struct sockaddr_storage spp_address;
 *     uint32_t                spp_hbinterval;
 *     uint16_t                spp_pathmaxrxt;
 *     uint32_t                spp_pathmtu;
 *     uint32_t                spp_sackdelay;
 *     uint32_t                spp_flags;
 * };
 *
 *   spp_assoc_id    - (one-to-many style socket) This is filled in the
 *                     application, and identifies the association for
 *                     this query.
 *   spp_address     - This specifies which address is of interest.
 *   spp_hbinterval  - This contains the value of the heartbeat interval,
 *                     in milliseconds.  If a  value of zero
 *                     is present in this field then no changes are to
 *                     be made to this parameter.
 *   spp_pathmaxrxt  - This contains the maximum number of
 *                     retransmissions before this address shall be
 *                     considered unreachable. If a  value of zero
 *                     is present in this field then no changes are to
 *                     be made to this parameter.
 *   spp_pathmtu     - When Path MTU discovery is disabled the value
 *                     specified here will be the "fixed" path mtu.
 *                     Note that if the spp_address field is empty
 *                     then all associations on this address will
 *                     have this fixed path mtu set upon them.
 *
 *   spp_sackdelay   - When delayed sack is enabled, this value specifies
 *                     the number of milliseconds that sacks will be delayed
 *                     for. This value will apply to all addresses of an
 *                     association if the spp_address field is empty. Note
 *                     also, that if delayed sack is enabled and this
 *                     value is set to 0, no change is made to the last
 *                     recorded delayed sack timer value.
 *
 *   spp_flags       - These flags are used to control various features
 *                     on an association. The flag field may contain
 *                     zero or more of the following options.
 *
 *                     SPP_HB_ENABLE  - Enable heartbeats on the
 *                     specified address. Note that if the address
 *                     field is empty all addresses for the association
 *                     have heartbeats enabled upon them.
 *
 *                     SPP_HB_DISABLE - Disable heartbeats on the
 *                     speicifed address. Note that if the address
 *                     field is empty all addresses for the association
 *                     will have their heartbeats disabled. Note also
 *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
 *                     mutually exclusive, only one of these two should
 *                     be specified. Enabling both fields will have
 *                     undetermined results.
 *
 *                     SPP_HB_DEMAND - Request a user initiated heartbeat
 *                     to be made immediately.
 *
 *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
 *                     heartbeat delayis to be set to the value of 0
 *                     milliseconds.
 *
 *                     SPP_PMTUD_ENABLE - This field will enable PMTU
 *                     discovery upon the specified address. Note that
 *                     if the address feild is empty then all addresses
 *                     on the association are effected.
 *
 *                     SPP_PMTUD_DISABLE - This field will disable PMTU
 *                     discovery upon the specified address. Note that
 *                     if the address feild is empty then all addresses
 *                     on the association are effected. Not also that
 *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
 *                     exclusive. Enabling both will have undetermined
 *                     results.
 *
 *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
 *                     on delayed sack. The time specified in spp_sackdelay
 *                     is used to specify the sack delay for this address. Note
 *                     that if spp_address is empty then all addresses will
 *                     enable delayed sack and take on the sack delay
 *                     value specified in spp_sackdelay.
 *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
 *                     off delayed sack. If the spp_address field is blank then
 *                     delayed sack is disabled for the entire association. Note
 *                     also that this field is mutually exclusive to
 *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
 *                     results.
 */
static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
				       struct sctp_transport   *trans,
				       struct sctp_association *asoc,
				       struct sctp_sock        *sp,
				       int                      hb_change,
				       int                      pmtud_change,
				       int                      sackdelay_change)
{
	int error;

	if (params->spp_flags & SPP_HB_DEMAND && trans) {
		struct net *net = sock_net(trans->asoc->base.sk);

		error = sctp_primitive_REQUESTHEARTBEAT(net, trans->asoc, trans);
		if (error)
			return error;
	}

	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
	 * this field is ignored.  Note also that a value of zero indicates
	 * the current setting should be left unchanged.
	 */
	if (params->spp_flags & SPP_HB_ENABLE) {

		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
		 * set.  This lets us use 0 value when this flag
		 * is set.
		 */
		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
			params->spp_hbinterval = 0;

		if (params->spp_hbinterval ||
		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
			if (trans) {
				trans->hbinterval =
				    msecs_to_jiffies(params->spp_hbinterval);
			} else if (asoc) {
				asoc->hbinterval =
				    msecs_to_jiffies(params->spp_hbinterval);
			} else {
				sp->hbinterval = params->spp_hbinterval;
			}
		}
	}

	if (hb_change) {
		if (trans) {
			trans->param_flags =
				(trans->param_flags & ~SPP_HB) | hb_change;
		} else if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_HB) | hb_change;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_HB) | hb_change;
		}
	}

	/* When Path MTU discovery is disabled the value specified here will
	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
	 * include the flag SPP_PMTUD_DISABLE for this field to have any
	 * effect).
	 */
	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
		if (trans) {
			trans->pathmtu = params->spp_pathmtu;
			sctp_assoc_sync_pmtu(sctp_opt2sk(sp), asoc);
		} else if (asoc) {
			asoc->pathmtu = params->spp_pathmtu;
			sctp_frag_point(asoc, params->spp_pathmtu);
		} else {
			sp->pathmtu = params->spp_pathmtu;
		}
	}

	if (pmtud_change) {
		if (trans) {
			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
				(params->spp_flags & SPP_PMTUD_ENABLE);
			trans->param_flags =
				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
			if (update) {
				sctp_transport_pmtu(trans, sctp_opt2sk(sp));
				sctp_assoc_sync_pmtu(sctp_opt2sk(sp), asoc);
			}
		} else if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
		}
	}

	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
	 * value of this field is ignored.  Note also that a value of zero
	 * indicates the current setting should be left unchanged.
	 */
	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
		if (trans) {
			trans->sackdelay =
				msecs_to_jiffies(params->spp_sackdelay);
		} else if (asoc) {
			asoc->sackdelay =
				msecs_to_jiffies(params->spp_sackdelay);
		} else {
			sp->sackdelay = params->spp_sackdelay;
		}
	}

	if (sackdelay_change) {
		if (trans) {
			trans->param_flags =
				(trans->param_flags & ~SPP_SACKDELAY) |
				sackdelay_change;
		} else if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_SACKDELAY) |
				sackdelay_change;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_SACKDELAY) |
				sackdelay_change;
		}
	}

	/* Note that a value of zero indicates the current setting should be
	   left unchanged.
	 */
	if (params->spp_pathmaxrxt) {
		if (trans) {
			trans->pathmaxrxt = params->spp_pathmaxrxt;
		} else if (asoc) {
			asoc->pathmaxrxt = params->spp_pathmaxrxt;
		} else {
			sp->pathmaxrxt = params->spp_pathmaxrxt;
		}
	}

	return 0;
}

static int sctp_setsockopt_peer_addr_params(struct sock *sk,
					    char __user *optval,
					    unsigned int optlen)
{
	struct sctp_paddrparams  params;
	struct sctp_transport   *trans = NULL;
	struct sctp_association *asoc = NULL;
	struct sctp_sock        *sp = sctp_sk(sk);
	int error;
	int hb_change, pmtud_change, sackdelay_change;

	if (optlen != sizeof(struct sctp_paddrparams))
		return - EINVAL;

	if (copy_from_user(&params, optval, optlen))
		return -EFAULT;

	/* Validate flags and value parameters. */
	hb_change        = params.spp_flags & SPP_HB;
	pmtud_change     = params.spp_flags & SPP_PMTUD;
	sackdelay_change = params.spp_flags & SPP_SACKDELAY;

	if (hb_change        == SPP_HB ||
	    pmtud_change     == SPP_PMTUD ||
	    sackdelay_change == SPP_SACKDELAY ||
	    params.spp_sackdelay > 500 ||
	    (params.spp_pathmtu &&
	     params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
		return -EINVAL;

	/* If an address other than INADDR_ANY is specified, and
	 * no transport is found, then the request is invalid.
	 */
	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
		trans = sctp_addr_id2transport(sk, &params.spp_address,
					       params.spp_assoc_id);
		if (!trans)
			return -EINVAL;
	}

	/* Get association, if assoc_id != 0 and the socket is a one
	 * to many style socket, and an association was not found, then
	 * the id was invalid.
	 */
	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
		return -EINVAL;

	/* Heartbeat demand can only be sent on a transport or
	 * association, but not a socket.
	 */
	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
		return -EINVAL;

	/* Process parameters. */
	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
					    hb_change, pmtud_change,
					    sackdelay_change);

	if (error)
		return error;

	/* If changes are for association, also apply parameters to each
	 * transport.
	 */
	if (!trans && asoc) {
		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
				transports) {
			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
						    hb_change, pmtud_change,
						    sackdelay_change);
		}
	}

	return 0;
}

/*
 * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
 *
 * This option will effect the way delayed acks are performed.  This
 * option allows you to get or set the delayed ack time, in
 * milliseconds.  It also allows changing the delayed ack frequency.
 * Changing the frequency to 1 disables the delayed sack algorithm.  If
 * the assoc_id is 0, then this sets or gets the endpoints default
 * values.  If the assoc_id field is non-zero, then the set or get
 * effects the specified association for the one to many model (the
 * assoc_id field is ignored by the one to one model).  Note that if
 * sack_delay or sack_freq are 0 when setting this option, then the
 * current values will remain unchanged.
 *
 * struct sctp_sack_info {
 *     sctp_assoc_t            sack_assoc_id;
 *     uint32_t                sack_delay;
 *     uint32_t                sack_freq;
 * };
 *
 * sack_assoc_id -  This parameter, indicates which association the user
 *    is performing an action upon.  Note that if this field's value is
 *    zero then the endpoints default value is changed (effecting future
 *    associations only).
 *
 * sack_delay -  This parameter contains the number of milliseconds that
 *    the user is requesting the delayed ACK timer be set to.  Note that
 *    this value is defined in the standard to be between 200 and 500
 *    milliseconds.
 *
 * sack_freq -  This parameter contains the number of packets that must
 *    be received before a sack is sent without waiting for the delay
 *    timer to expire.  The default value for this is 2, setting this
 *    value to 1 will disable the delayed sack algorithm.
 */

static int sctp_setsockopt_delayed_ack(struct sock *sk,
				       char __user *optval, unsigned int optlen)
{
	struct sctp_sack_info    params;
	struct sctp_transport   *trans = NULL;
	struct sctp_association *asoc = NULL;
	struct sctp_sock        *sp = sctp_sk(sk);

	if (optlen == sizeof(struct sctp_sack_info)) {
		if (copy_from_user(&params, optval, optlen))
			return -EFAULT;

		if (params.sack_delay == 0 && params.sack_freq == 0)
			return 0;
	} else if (optlen == sizeof(struct sctp_assoc_value)) {
		pr_warn("Use of struct sctp_assoc_value in delayed_ack socket option deprecated\n");
		pr_warn("Use struct sctp_sack_info instead\n");
		if (copy_from_user(&params, optval, optlen))
			return -EFAULT;

		if (params.sack_delay == 0)
			params.sack_freq = 1;
		else
			params.sack_freq = 0;
	} else
		return - EINVAL;

	/* Validate value parameter. */
	if (params.sack_delay > 500)
		return -EINVAL;

	/* Get association, if sack_assoc_id != 0 and the socket is a one
	 * to many style socket, and an association was not found, then
	 * the id was invalid.
	 */
	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
		return -EINVAL;

	if (params.sack_delay) {
		if (asoc) {
			asoc->sackdelay =
				msecs_to_jiffies(params.sack_delay);
			asoc->param_flags =
				(asoc->param_flags & ~SPP_SACKDELAY) |
				SPP_SACKDELAY_ENABLE;
		} else {
			sp->sackdelay = params.sack_delay;
			sp->param_flags =
				(sp->param_flags & ~SPP_SACKDELAY) |
				SPP_SACKDELAY_ENABLE;
		}
	}

	if (params.sack_freq == 1) {
		if (asoc) {
			asoc->param_flags =
				(asoc->param_flags & ~SPP_SACKDELAY) |
				SPP_SACKDELAY_DISABLE;
		} else {
			sp->param_flags =
				(sp->param_flags & ~SPP_SACKDELAY) |
				SPP_SACKDELAY_DISABLE;
		}
	} else if (params.sack_freq > 1) {
		if (asoc) {
			asoc->sackfreq = params.sack_freq;
			asoc->param_flags =
				(asoc->param_flags & ~SPP_SACKDELAY) |
				SPP_SACKDELAY_ENABLE;
		} else {
			sp->sackfreq = params.sack_freq;
			sp->param_flags =
				(sp->param_flags & ~SPP_SACKDELAY) |
				SPP_SACKDELAY_ENABLE;
		}
	}

	/* If change is for association, also apply to each transport. */
	if (asoc) {
		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
				transports) {
			if (params.sack_delay) {
				trans->sackdelay =
					msecs_to_jiffies(params.sack_delay);
				trans->param_flags =
					(trans->param_flags & ~SPP_SACKDELAY) |
					SPP_SACKDELAY_ENABLE;
			}
			if (params.sack_freq == 1) {
				trans->param_flags =
					(trans->param_flags & ~SPP_SACKDELAY) |
					SPP_SACKDELAY_DISABLE;
			} else if (params.sack_freq > 1) {
				trans->sackfreq = params.sack_freq;
				trans->param_flags =
					(trans->param_flags & ~SPP_SACKDELAY) |
					SPP_SACKDELAY_ENABLE;
			}
		}
	}

	return 0;
}

/* 7.1.3 Initialization Parameters (SCTP_INITMSG)
 *
 * Applications can specify protocol parameters for the default association
 * initialization.  The option name argument to setsockopt() and getsockopt()
 * is SCTP_INITMSG.
 *
 * Setting initialization parameters is effective only on an unconnected
 * socket (for UDP-style sockets only future associations are effected
 * by the change).  With TCP-style sockets, this option is inherited by
 * sockets derived from a listener socket.
 */
static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
{
	struct sctp_initmsg sinit;
	struct sctp_sock *sp = sctp_sk(sk);

	if (optlen != sizeof(struct sctp_initmsg))
		return -EINVAL;
	if (copy_from_user(&sinit, optval, optlen))
		return -EFAULT;

	if (sinit.sinit_num_ostreams)
		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
	if (sinit.sinit_max_instreams)
		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
	if (sinit.sinit_max_attempts)
		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
	if (sinit.sinit_max_init_timeo)
		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;

	return 0;
}

/*
 * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
 *
 *   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_sndrcvinfo structure.
 *   The application that wishes to use this socket option simply passes
 *   in to this call the sctp_sndrcvinfo structure defined in Section
 *   5.2.2) The input parameters accepted by this call include
 *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
 *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
 *   to this call if the caller is using the UDP model.
 */
static int sctp_setsockopt_default_send_param(struct sock *sk,
					      char __user *optval,
					      unsigned int optlen)
{
	struct sctp_sndrcvinfo info;
	struct sctp_association *asoc;
	struct sctp_sock *sp = sctp_sk(sk);

	if (optlen != sizeof(struct sctp_sndrcvinfo))
		return -EINVAL;
	if (copy_from_user(&info, optval, optlen))
		return -EFAULT;

	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		asoc->default_stream = info.sinfo_stream;
		asoc->default_flags = info.sinfo_flags;
		asoc->default_ppid = info.sinfo_ppid;
		asoc->default_context = info.sinfo_context;
		asoc->default_timetolive = info.sinfo_timetolive;
	} else {
		sp->default_stream = info.sinfo_stream;
		sp->default_flags = info.sinfo_flags;
		sp->default_ppid = info.sinfo_ppid;
		sp->default_context = info.sinfo_context;
		sp->default_timetolive = info.sinfo_timetolive;
	}

	return 0;
}

/* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
 *
 * Requests that the local SCTP stack use the enclosed peer address as
 * the association primary.  The enclosed address must be one of the
 * association peer's addresses.
 */
static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
					unsigned int optlen)
{
	struct sctp_prim prim;
	struct sctp_transport *trans;

	if (optlen != sizeof(struct sctp_prim))
		return -EINVAL;

	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
		return -EFAULT;

	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
	if (!trans)
		return -EINVAL;

	sctp_assoc_set_primary(trans->asoc, trans);

	return 0;
}

/*
 * 7.1.5 SCTP_NODELAY
 *
 * Turn on/off any Nagle-like algorithm.  This means that packets are
 * generally sent as soon as possible and no unnecessary delays are
 * introduced, at the cost of more packets in the network.  Expects an
 *  integer boolean flag.
 */
static int sctp_setsockopt_nodelay(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)->nodelay = (val == 0) ? 0 : 1;
	return 0;
}

/*
 *
 * 7.1.1 SCTP_RTOINFO
 *
 * The protocol parameters used to initialize and bound retransmission
 * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
 * and modify these parameters.
 * All parameters are time values, in milliseconds.  A value of 0, when
 * modifying the parameters, indicates that the current value should not
 * be changed.
 *
 */
static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
{
	struct sctp_rtoinfo rtoinfo;
	struct sctp_association *asoc;

	if (optlen != sizeof (struct sctp_rtoinfo))
		return -EINVAL;

	if (copy_from_user(&rtoinfo, optval, optlen))
		return -EFAULT;

	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);

	/* Set the values to the specific association */
	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
		return -EINVAL;

	if (asoc) {
		if (rtoinfo.srto_initial != 0)
			asoc->rto_initial =
				msecs_to_jiffies(rtoinfo.srto_initial);
		if (rtoinfo.srto_max != 0)
			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
		if (rtoinfo.srto_min != 0)
			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
	} else {
		/* If there is no association or the association-id = 0
		 * set the values to the endpoint.
		 */
		struct sctp_sock *sp = sctp_sk(sk);

		if (rtoinfo.srto_initial != 0)
			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
		if (rtoinfo.srto_max != 0)
			sp->rtoinfo.srto_max = rtoinfo.srto_max;
		if (rtoinfo.srto_min != 0)
			sp->rtoinfo.srto_min = rtoinfo.srto_min;
	}

	return 0;
}

/*
 *
 * 7.1.2 SCTP_ASSOCINFO
 *
 * This option is used to tune the maximum retransmission attempts
 * of the association.
 * Returns an error if the new association retransmission value is
 * greater than the sum of the retransmission value  of the peer.
 * See [SCTP] for more information.
 *
 */
static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
{

	struct sctp_assocparams assocparams;
	struct sctp_association *asoc;

	if (optlen != sizeof(struct sctp_assocparams))
		return -EINVAL;
	if (copy_from_user(&assocparams, optval, optlen))
		return -EFAULT;

	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);

	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
		return -EINVAL;

	/* Set the values to the specific association */
	if (asoc) {
		if (assocparams.sasoc_asocmaxrxt != 0) {
			__u32 path_sum = 0;
			int   paths = 0;
			struct sctp_transport *peer_addr;

			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
					transports) {
				path_sum += peer_addr->pathmaxrxt;
				paths++;
			}

			/* Only validate asocmaxrxt if we have more than
			 * one path/transport.  We do this because path
			 * retransmissions are only counted when we have more
			 * then one path.
			 */
			if (paths > 1 &&
			    assocparams.sasoc_asocmaxrxt > path_sum)
				return -EINVAL;

			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
		}

		if (assocparams.sasoc_cookie_life != 0) {
			asoc->cookie_life.tv_sec =
					assocparams.sasoc_cookie_life / 1000;
			asoc->cookie_life.tv_usec =
					(assocparams.sasoc_cookie_life % 1000)
					* 1000;
		}
	} else {
		/* Set the values to the endpoint */
		struct sctp_sock *sp = sctp_sk(sk);

		if (assocparams.sasoc_asocmaxrxt != 0)
			sp->assocparams.sasoc_asocmaxrxt =
						assocparams.sasoc_asocmaxrxt;
		if (assocparams.sasoc_cookie_life != 0)
			sp->assocparams.sasoc_cookie_life =
						assocparams.sasoc_cookie_life;
	}
	return 0;
}

/*
 * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
 *
 * This socket option is a boolean flag which turns on or off mapped V4
 * addresses.  If this option is turned on and the socket is type
 * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
 * If this option is turned off, then no mapping will be done of V4
 * addresses and a user will receive both PF_INET6 and PF_INET type
 * addresses on the socket.
 */
static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
{
	int val;
	struct sctp_sock *sp = sctp_sk(sk);

	if (optlen < sizeof(int))
		return -EINVAL;
	if (get_user(val, (int __user *)optval))
		return -EFAULT;
	if (val)
		sp->v4mapped = 1;
	else
		sp->v4mapped = 0;

	return 0;
}

/*
 * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
 * This option will get or set the maximum size to put in any outgoing
 * SCTP DATA chunk.  If a message is larger than this size it will be
 * fragmented by SCTP into the specified size.  Note that the underlying
 * SCTP implementation may fragment into smaller sized chunks when the
 * PMTU of the underlying association is smaller than the value set by
 * the user.  The default value for this option is '0' which indicates
 * the user is NOT limiting fragmentation and only the PMTU will effect
 * SCTP's choice of DATA chunk size.  Note also that values set larger
 * than the maximum size of an IP datagram will effectively let SCTP
 * control fragmentation (i.e. the same as setting this option to 0).
 *
 * The following structure is used to access and modify this parameter:
 *
 * struct sctp_assoc_value {
 *   sctp_assoc_t assoc_id;
 *   uint32_t assoc_value;
 * };
 *
 * assoc_id:  This parameter is ignored for one-to-one style sockets.
 *    For one-to-many style sockets this parameter indicates which
 *    association the user is performing an action upon.  Note that if
 *    this field's value is zero then the endpoints default value is
 *    changed (effecting future associations only).
 * assoc_value:  This parameter specifies the maximum size in bytes.
 */
static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
{
	struct sctp_assoc_value params;
	struct sctp_association *asoc;
	struct sctp_sock *sp = sctp_sk(sk);
	int val;

	if (optlen == sizeof(int)) {