linux/include/net/sctp/ulpevent.h
Geir Ola Vaagland 2347c80ff1 net: sctp: implement rfc6458, 5.3.6. SCTP_NXTINFO cmsg support
This patch implements section 5.3.6. of RFC6458, that is, support
for 'SCTP Next Receive Information Structure' (SCTP_NXTINFO) which
is placed into ancillary data cmsghdr structure for each recvmsg()
call, if this information is already available when delivering the
current message.

This option can be enabled/disabled via setsockopt(2) on SOL_SCTP
level by setting an int value with 1/0 for SCTP_RECVNXTINFO in
user space applications as per RFC6458, section 8.1.30.

The sctp_nxtinfo structure is defined as per RFC as below ...

  struct sctp_nxtinfo {
    uint16_t nxt_sid;
    uint16_t nxt_flags;
    uint32_t nxt_ppid;
    uint32_t nxt_length;
    sctp_assoc_t nxt_assoc_id;
  };

... and provided under cmsg_level IPPROTO_SCTP, cmsg_type
SCTP_NXTINFO, while cmsg_data[] contains struct sctp_nxtinfo.

Joint work with Daniel Borkmann.

Signed-off-by: Geir Ola Vaagland <geirola@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 14:40:03 -07:00

163 lines
4.9 KiB
C

/* SCTP kernel implementation
* (C) Copyright IBM Corp. 2001, 2004
* Copyright (c) 1999-2000 Cisco, Inc.
* Copyright (c) 1999-2001 Motorola, Inc.
* Copyright (c) 2001 Intel Corp.
* Copyright (c) 2001 Nokia, Inc.
* Copyright (c) 2001 La Monte H.P. Yarroll
*
* These are the definitions needed for the sctp_ulpevent type. The
* sctp_ulpevent type is used to carry information from the state machine
* upwards to the ULP.
*
* This file is part of the SCTP kernel implementation
*
* This SCTP implementation is free software;
* you can redistribute it and/or modify it under the terms of
* the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This SCTP implementation is distributed in the hope that it
* will be useful, but WITHOUT ANY WARRANTY; without even the implied
* ************************
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU CC; see the file COPYING. If not, see
* <http://www.gnu.org/licenses/>.
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers <linux-sctp@vger.kernel.org>
*
* Written or modified by:
* Jon Grimm <jgrimm@us.ibm.com>
* La Monte H.P. Yarroll <piggy@acm.org>
* Karl Knutson <karl@athena.chicago.il.us>
* Sridhar Samudrala <sri@us.ibm.com>
*/
#ifndef __sctp_ulpevent_h__
#define __sctp_ulpevent_h__
/* A structure to carry information to the ULP (e.g. Sockets API) */
/* Warning: This sits inside an skb.cb[] area. Be very careful of
* growing this structure as it is at the maximum limit now.
*/
struct sctp_ulpevent {
struct sctp_association *asoc;
__u16 stream;
__u16 ssn;
__u16 flags;
__u32 ppid;
__u32 tsn;
__u32 cumtsn;
int msg_flags;
int iif;
unsigned int rmem_len;
};
/* Retrieve the skb this event sits inside of. */
static inline struct sk_buff *sctp_event2skb(const struct sctp_ulpevent *ev)
{
return container_of((void *)ev, struct sk_buff, cb);
}
/* Retrieve & cast the event sitting inside the skb. */
static inline struct sctp_ulpevent *sctp_skb2event(struct sk_buff *skb)
{
return (struct sctp_ulpevent *)skb->cb;
}
void sctp_ulpevent_free(struct sctp_ulpevent *);
int sctp_ulpevent_is_notification(const struct sctp_ulpevent *);
unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list);
struct sctp_ulpevent *sctp_ulpevent_make_assoc_change(
const struct sctp_association *asoc,
__u16 flags,
__u16 state,
__u16 error,
__u16 outbound,
__u16 inbound,
struct sctp_chunk *chunk,
gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change(
const struct sctp_association *asoc,
const struct sockaddr_storage *aaddr,
int flags,
int state,
int error,
gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_remote_error(
const struct sctp_association *asoc,
struct sctp_chunk *chunk,
__u16 flags,
gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
const struct sctp_association *asoc,
struct sctp_chunk *chunk,
__u16 flags,
__u32 error,
gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
const struct sctp_association *asoc,
__u16 flags,
gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
const struct sctp_association *asoc,
__u32 indication, gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
const struct sctp_association *asoc, gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
struct sctp_chunk *chunk,
gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_authkey(
const struct sctp_association *asoc, __u16 key_id,
__u32 indication, gfp_t gfp);
struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
const struct sctp_association *asoc, gfp_t gfp);
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 sock *sk);
__u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event);
/* Is this event type enabled? */
static inline int sctp_ulpevent_type_enabled(__u16 sn_type,
struct sctp_event_subscribe *mask)
{
char *amask = (char *) mask;
return amask[sn_type - SCTP_SN_TYPE_BASE];
}
/* Given an event subscription, is this event enabled? */
static inline int sctp_ulpevent_is_enabled(const struct sctp_ulpevent *event,
struct sctp_event_subscribe *mask)
{
__u16 sn_type;
int enabled = 1;
if (sctp_ulpevent_is_notification(event)) {
sn_type = sctp_ulpevent_get_notification_type(event);
enabled = sctp_ulpevent_type_enabled(sn_type, mask);
}
return enabled;
}
#endif /* __sctp_ulpevent_h__ */