- 根目录:
- net
- sctp
- ulpevent.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 functions manipulate an sctp event. The struct ulpevent is used
* to carry notifications and data to the ULP (sockets).
*
* 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>
* Ardelle Fan <ardelle.fan@intel.com>
* Sridhar Samudrala <sri@us.ibm.com>
*/
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/skbuff.h>
#include <net/sctp/structs.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>
static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
struct sctp_association *asoc);
static void sctp_ulpevent_release_data(struct sctp_ulpevent *event);
static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event);
/* Initialize an ULP event from an given skb. */
static void sctp_ulpevent_init(struct sctp_ulpevent *event,
int msg_flags,
unsigned int len)
{
memset(event, 0, sizeof(struct sctp_ulpevent));
event->msg_flags = msg_flags;
event->rmem_len = len;
}
/* Create a new sctp_ulpevent. */
static struct sctp_ulpevent *sctp_ulpevent_new(int size, int msg_flags,
gfp_t gfp)
{
struct sctp_ulpevent *event;
struct sk_buff *skb;
skb = alloc_skb(size, gfp);
if (!skb)
goto fail;
event = sctp_skb2event(skb);
sctp_ulpevent_init(event, msg_flags, skb->truesize);
return event;
fail:
return NULL;
}
/* Is this a MSG_NOTIFICATION? */
int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event)
{
return MSG_NOTIFICATION == (event->msg_flags & MSG_NOTIFICATION);
}
/* Hold the association in case the msg_name needs read out of
* the association.
*/
static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
const struct sctp_association *asoc)
{
struct sk_buff *skb;
/* Cast away the const, as we are just wanting to
* bump the reference count.
*/
sctp_association_hold((struct sctp_association *)asoc);
skb = sctp_event2skb(event);
event->asoc = (struct sctp_association *)asoc;
atomic_add(event->rmem_len, &event->asoc->rmem_alloc);
sctp_skb_set_owner_r(skb, asoc->base.sk);
}
/* A simple destructor to give up the reference to the association. */
static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
{
struct sctp_association *asoc = event->asoc;
atomic_sub(event->rmem_len, &asoc->rmem_alloc);
sctp_association_put(asoc);
}
/* Create and initialize an SCTP_ASSOC_CHANGE event.
*
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* Communication notifications inform the ULP that an SCTP association
* has either begun or ended. The identifier for a new association is
* provided by this notification.
*
* Note: There is no field checking here. If a field is unused it will be
* zero'd out.
*/
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 *event;
struct sctp_assoc_change *sac;
struct sk_buff *skb;
/* If the lower layer passed in the chunk, it will be
* an ABORT, so we need to include it in the sac_info.
*/
if (chunk) {
/* Copy the chunk data to a new skb and reserve enough
* head room to use as notification.
*/
skb = skb_copy_expand(chunk->skb,
sizeof(struct sctp_assoc_change), 0, gfp);
if (!skb)
goto fail;
/* Embed the event fields inside the cloned skb. */
event = sctp_skb2event(skb);
sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
/* Include the notification structure */
sac = (struct sctp_assoc_change *)
skb_push(skb, sizeof(struct sctp_assoc_change));
/* Trim the buffer to the right length. */
skb_trim(skb, sizeof(struct sctp_assoc_change) +
ntohs(chunk->chunk_hdr->length) -
sizeof(sctp_chunkhdr_t));
} else {
event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
MSG_NOTIFICATION, gfp);
if (!event)
goto fail;
skb = sctp_event2skb(event);
sac = (struct sctp_assoc_change *) skb_put(skb,
sizeof(struct sctp_assoc_change));
}
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_type:
* It should be SCTP_ASSOC_CHANGE.
*/
sac->sac_type = SCTP_ASSOC_CHANGE;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_state: 32 bits (signed integer)
* This field holds one of a number of values that communicate the
* event that happened to the association.
*/
sac->sac_state = state;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_flags: 16 bits (unsigned integer)
* Currently unused.
*/
sac->sac_flags = 0;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_length: sizeof (__u32)
* This field is the total length of the notification data, including
* the notification header.
*/
sac->sac_length = skb->len;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_error: 32 bits (signed integer)
*
* If the state was reached due to a error condition (e.g.
* COMMUNICATION_LOST) any relevant error information is available in
* this field. This corresponds to the protocol error codes defined in
* [SCTP].
*/
sac->sac_error = error;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_outbound_streams: 16 bits (unsigned integer)
* sac_inbound_streams: 16 bits (unsigned integer)
*
* The maximum number of streams allowed in each direction are
* available in sac_outbound_streams and sac_inbound streams.
*/
sac->sac_outbound_streams = outbound;
sac->sac_inbound_streams = inbound;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* sac_assoc_id: sizeof (sctp_assoc_t)
*
* The association id field, holds the identifier for the association.
* All notifications for a given association have the same association
* identifier. For TCP style socket, this field is ignored.
*/
sctp_ulpevent_set_owner(event, asoc);
sac->sac_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
/* Create and initialize an SCTP_PEER_ADDR_CHANGE event.
*
* Socket Extensions for SCTP - draft-01
* 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* When a destination address on a multi-homed peer encounters a change
* an interface details event is sent.
*/
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 *event;
struct sctp_paddr_change *spc;
struct sk_buff *skb;
event = sctp_ulpevent_new(sizeof(struct sctp_paddr_change),
MSG_NOTIFICATION, gfp);
if (!event)
goto fail;
skb = sctp_event2skb(event);
spc = (struct sctp_paddr_change *)
skb_put(skb, sizeof(struct sctp_paddr_change));
/* Sockets API Extensions for SCTP
* Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* spc_type:
*
* It should be SCTP_PEER_ADDR_CHANGE.
*/
spc->spc_type = SCTP_PEER_ADDR_CHANGE;
/* Sockets API Extensions for SCTP
* Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* spc_length: sizeof (__u32)
*
* This field is the total length of the notification data, including
* the notification header.
*/
spc->spc_length = sizeof(struct sctp_paddr_change);
/* Sockets API Extensions for SCTP
* Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* spc_flags: 16 bits (unsigned integer)
* Currently unused.
*/
spc->spc_flags = 0;
/* Sockets API Extensions for SCTP
* Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* spc_state: 32 bits (signed integer)
*
* This field holds one of a number of values that communicate the
* event that happened to the address.
*/
spc->spc_state = state;
/* Sockets API Extensions for SCTP
* Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* spc_error: 32 bits (signed integer)
*
* If the state was reached due to any error condition (e.g.
* ADDRESS_UNREACHABLE) any relevant error information is available in
* this field.
*/
spc->spc_error = error;
/* Socket Extensions for SCTP
* 5.3.1.1 SCTP_ASSOC_CHANGE
*
* spc_assoc_id: sizeof (sctp_assoc_t)
*
* The association id field, holds the identifier for the association.
* All notifications for a given association have the same association
* identifier. For TCP style socket, this field is ignored.
*/
sctp_ulpevent_set_owner(event, asoc);
spc->spc_assoc_id = sctp_assoc2id(asoc);
/* Sockets API Extensions for SCTP
* Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
*
* spc_aaddr: sizeof (struct sockaddr_storage)
*
* The affected address field, holds the remote peer's address that is
* encountering the change of state.
*/
memcpy(&spc->spc_aaddr, aaddr, sizeof(struct sockaddr_storage));
/* Map ipv4 address into v4-mapped-on-v6 address. */
sctp_get_pf_specific(asoc->base.sk->sk_family)->addr_to_user(
sctp_sk(asoc->base.sk),
(union sctp_addr *)&spc->spc_aaddr);
return event;
fail:
return NULL;
}
/* Create and initialize an SCTP_REMOTE_ERROR notification.
*
* Note: This assumes that the chunk->skb->data already points to the
* operation error payload.
*
* Socket Extensions for SCTP - draft-01
* 5.3.1.3 SCTP_REMOTE_ERROR
*
* A remote peer may send an Operational Error message to its peer.
* This message indicates a variety of error conditions on an
* association. The entire error TLV as it appears on the wire is
* included in a SCTP_REMOTE_ERROR event. Please refer to the SCTP
* specification [SCTP] and any extensions for a list of possible
* error formats.
*/
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 *event;
struct sctp_remote_error *sre;
struct sk_buff *skb;
sctp_errhdr_t *ch;
__be16 cause;
int elen;
ch = (sctp_errhdr_t *)(chunk->skb->data);
cause = ch->cause;
elen = WORD_ROUND(ntohs(ch->length)) - sizeof(sctp_errhdr_t);
/* Pull off the ERROR header. */
skb_pull(chunk->skb, sizeof(sctp_errhdr_t));
/* Copy the skb to a new skb with room for us to prepend
* notification with.
*/
skb = skb_copy_expand(chunk->skb, sizeof(*sre), 0, gfp);
/* Pull off the rest of the cause TLV from the chunk. */
skb_pull(chunk->skb, elen);
if (!skb)
goto fail;
/* Embed the event fields inside the cloned skb. */
event = sctp_skb2event(skb);
sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
sre = (struct sctp_remote_error *) skb_push(skb, sizeof(*sre));
/* Trim the buffer to the right length. */
skb_trim(skb, sizeof(*sre) + elen);
/* RFC6458, Section 6.1.3. SCTP_REMOTE_ERROR */
memset(sre, 0, sizeof(*sre));
sre->sre_type = SCTP_REMOTE_ERROR;
sre->sre_flags = 0;
sre->sre_length = skb->len;
sre->sre_error = cause;
sctp_ulpevent_set_owner(event, asoc);
sre->sre_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
/* Create and initialize a SCTP_SEND_FAILED notification.
*
* Socket Extensions for SCTP - draft-01
* 5.3.1.4 SCTP_SEND_FAILED
*/
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 *event;
struct sctp_send_failed *ssf;
struct sk_buff *skb;
/* Pull off any padding. */
int len = ntohs(chunk->chunk_hdr->length);
/* Make skb with more room so we can prepend notification. */
skb = skb_copy_expand(chunk->skb,
sizeof(struct sctp_send_failed), /* headroom */
0, /* tailroom */
gfp);
if (!skb)
goto fail;
/* Pull off the common chunk header and DATA header. */
skb_pull(skb, sizeof(struct sctp_data_chunk));
len -= sizeof(struct sctp_data_chunk);
/* Embed the event fields inside the cloned skb. */
event = sctp_skb2event(skb);
sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
ssf = (struct sctp_send_failed *)
skb_push(skb, sizeof(struct sctp_send_failed));
/* Socket Extensions for SCTP
* 5.3.1.4 SCTP_SEND_FAILED
*
* ssf_type:
* It should be SCTP_SEND_FAILED.
*/
ssf->ssf_type = SCTP_SEND_FAILED;
/* Socket Extensions for SCTP
* 5.3.1.4 SCTP_SEND_FAILED
*
* ssf_flags: 16 bits (unsigned integer)
* The flag value will take one of the following values
*
* SCTP_DATA_UNSENT - Indicates that the data was never put on
* the wire.
*
* SCTP_DATA_SENT - Indicates that the data was put on the wire.
* Note that this does not necessarily mean that the
* data was (or was not) successfully delivered.
*/
ssf->ssf_flags = flags;
/* Socket Extensions for SCTP
* 5.3.1.4 SCTP_SEND_FAILED
*
* ssf_length: sizeof (__u32)
* This field is the total length of the notification data, including
* the notification header.
*/
ssf->ssf_length = sizeof(struct sctp_send_failed) + len;
skb_trim(skb, ssf->ssf_length);
/* Socket Extensions for SCTP
* 5.3.1.4 SCTP_SEND_FAILED
*
* ssf_error: 16 bits (unsigned integer)
* This value represents the reason why the send failed, and if set,
* will be a SCTP protocol error code as defined in [SCTP] section
* 3.3.10.
*/
ssf->ssf_error = error;
/* Socket Extensions for SCTP
* 5.3.1.4 SCTP_SEND_FAILED
*
* ssf_info: sizeof (struct sctp_sndrcvinfo)
* The original send information associated with the undelivered
* message.
*/
memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo));
/* Per TSVWG discussion with Randy. Allow the application to
* reassemble a fragmented message.
*/
ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags;
/* Socket Extensions for SCTP
* 5.3.1.4 SCTP_SEND_FAILED
*
* ssf_assoc_id: sizeof (sctp_assoc_t)
* The association id field, sf_assoc_id, holds the identifier for the
* association. All notifications for a given association have the
* same association identifier. For TCP style socket, this field is
* ignored.
*/
sctp_ulpevent_set_owner(event, asoc);
ssf->ssf_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
/* Create and initialize a SCTP_SHUTDOWN_EVENT notification.
*
* Socket Extensions for SCTP - draft-01
* 5.3.1.5 SCTP_SHUTDOWN_EVENT
*/
struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
const struct sctp_association *asoc,
__u16 flags, gfp_t gfp)
{
struct sctp_ulpevent *event;
struct sctp_shutdown_event *sse;
struct sk_buff *skb;
event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event),
MSG_NOTIFICATION, gfp);
if (!event)
goto fail;
skb = sctp_event2skb(event);
sse = (struct sctp_shutdown_event *)
skb_put(skb, sizeof(struct sctp_shutdown_event));
/* Socket Extensions for SCTP
* 5.3.1.5 SCTP_SHUTDOWN_EVENT
*
* sse_type
* It should be SCTP_SHUTDOWN_EVENT
*/
sse->sse_type = SCTP_SHUTDOWN_EVENT;
/* Socket Extensions for SCTP
* 5.3.1.5 SCTP_SHUTDOWN_EVENT
*
* sse_flags: 16 bits (unsigned integer)
* Currently unused.
*/
sse->sse_flags = 0;
/* Socket Extensions for SCTP
* 5.3.1.5 SCTP_SHUTDOWN_EVENT
*
* sse_length: sizeof (__u32)
* This field is the total length of the notification data, including
* the notification header.
*/
sse->sse_length = sizeof(struct sctp_shutdown_event);
/* Socket Extensions for SCTP
* 5.3.1.5 SCTP_SHUTDOWN_EVENT
*
* sse_assoc_id: sizeof (sctp_assoc_t)
* The association id field, holds the identifier for the association.
* All notifications for a given association have the same association
* identifier. For TCP style socket, this field is ignored.
*/
sctp_ulpevent_set_owner(event, asoc);
sse->sse_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
/* Create and initialize a SCTP_ADAPTATION_INDICATION notification.
*
* Socket Extensions for SCTP
* 5.3.1.6 SCTP_ADAPTATION_INDICATION
*/
struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
const struct sctp_association *asoc, gfp_t gfp)
{
struct sctp_ulpevent *event;
struct sctp_adaptation_event *sai;
struct sk_buff *skb;
event = sctp_ulpevent_new(sizeof(struct sctp_adaptation_event),
MSG_NOTIFICATION, gfp);
if (!event)
goto fail;
skb = sctp_event2skb(event);
sai = (struct sctp_adaptation_event *)
skb_put(skb, sizeof(struct sctp_adaptation_event));
sai->sai_type = SCTP_ADAPTATION_INDICATION;
sai->sai_flags = 0;
sai->sai_length = sizeof(struct sctp_adaptation_event);
sai->sai_adaptation_ind = asoc->peer.adaptation_ind;
sctp_ulpevent_set_owner(event, asoc);
sai->sai_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
/* A message has been received. Package this message as a notification
* to pass it to the upper layers. Go ahead and calculate the sndrcvinfo
* even if filtered out later.
*
* Socket Extensions for SCTP
* 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
*/
struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
struct sctp_chunk *chunk,
gfp_t gfp)
{
struct sctp_ulpevent *event = NULL;
struct sk_buff *skb;
size_t padding, len;
int rx_count;
/*
* check to see if we need to make space for this
* new skb, expand the rcvbuffer if needed, or drop
* the frame
*/
if (asoc->ep->rcvbuf_policy)
rx_count = atomic_read(&asoc->rmem_alloc);
else
rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
if (rx_count >= asoc->base.sk->sk_rcvbuf) {
if ((asoc->base.sk->sk_userlocks & SOCK_RCVBUF_LOCK) ||
(!sk_rmem_schedule(asoc->base.sk, chunk->skb,
chunk->skb->truesize)))
goto fail;
}
/* Clone the original skb, sharing the data. */
skb = skb_clone(chunk->skb, gfp);
if (!skb)
goto fail;
/* Now that all memory allocations for this chunk succeeded, we
* can mark it as received so the tsn_map is updated correctly.
*/
if (sctp_tsnmap_mark(&asoc->peer.tsn_map,
ntohl(chunk->subh.data_hdr->tsn),
chunk->transport))
goto fail_mark;
/* First calculate the padding, so we don't inadvertently
* pass up the wrong length to the user.
*
* RFC 2960 - Section 3.2 Chunk Field Descriptions
*
* The total length of a chunk(including Type, Length and Value fields)
* MUST be a multiple of 4 bytes. If the length of the chunk is not a
* multiple of 4 bytes, the sender MUST pad the chunk with all zero
* bytes and this padding is not included in the chunk length field.
* The sender should never pad with more than 3 bytes. The receiver
* MUST ignore the padding bytes.
*/
len = ntohs(chunk->chunk_hdr->length);
padding = WORD_ROUND(len) - len;
/* Fixup cloned skb with just this chunks data. */
skb_trim(skb, chunk->chunk_end - padding - skb->data);
/* Embed the event fields inside the cloned skb. */
event = sctp_skb2event(skb);
/* Initialize event with flags 0 and correct length
* Since this is a clone of the original skb, only account for
* the data of this chunk as other chunks will be accounted separately.
*/
sctp_ulpevent_init(event, 0, skb->len + sizeof(struct sk_buff));
sctp_ulpevent_receive_data(event, asoc);
event->stream = ntohs(chunk->subh.data_hdr->stream);
event->ssn = ntohs(chunk->subh.data_hdr->ssn);
event->ppid = chunk->subh.data_hdr->ppid;
if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
event->flags |= SCTP_UNORDERED;
event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
}
event->tsn = ntohl(chunk->subh.data_hdr->tsn);
event->msg_flags |= chunk->chunk_hdr->flags;
event->iif = sctp_chunk_iif(chunk);
return event;
fail_mark:
kfree_skb(skb);
fail:
return NULL;
}
/* Create a partial delivery related event.
*
* 5.3.1.7 SCTP_PARTIAL_DELIVERY_EVENT
*
* When a receiver is engaged in a partial delivery of a
* message this notification will be used to indicate
* various events.
*/
struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
const struct sctp_association *asoc, __u32 indication,
gfp_t gfp)
{
struct sctp_ulpevent *event;
struct sctp_pdapi_event *pd;
struct sk_buff *skb;
event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event),
MSG_NOTIFICATION, gfp);
if (!event)
goto fail;
skb = sctp_event2skb(event);
pd = (struct sctp_pdapi_event *)
skb_put(skb, sizeof(struct sctp_pdapi_event));
/* pdapi_type
* It should be SCTP_PARTIAL_DELIVERY_EVENT
*
* pdapi_flags: 16 bits (unsigned integer)
* Currently unused.
*/
pd->pdapi_type = SCTP_PARTIAL_DELIVERY_EVENT;
pd->pdapi_flags = 0;
/* pdapi_length: 32 bits (unsigned integer)
*
* This field is the total length of the notification data, including
* the notification header. It will generally be sizeof (struct
* sctp_pdapi_event).
*/
pd->pdapi_length = sizeof(struct sctp_pdapi_event);
/* pdapi_indication: 32 bits (unsigned integer)
*
* This field holds the indication being sent to the application.
*/
pd->pdapi_indication = indication;
/* pdapi_assoc_id: sizeof (sctp_assoc_t)
*
* The association id field, holds the identifier for the association.
*/
sctp_ulpevent_set_owner(event, asoc);
pd->pdapi_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
struct sctp_ulpevent *sctp_ulpevent_make_authkey(
const struct sctp_association *asoc, __u16 key_id,
__u32 indication, gfp_t gfp)
{
struct sctp_ulpevent *event;
struct sctp_authkey_event *ak;
struct sk_buff *skb;
event = sctp_ulpevent_new(sizeof(struct sctp_authkey_event),
MSG_NOTIFICATION, gfp);
if (!event)
goto fail;
skb = sctp_event2skb(event);
ak = (struct sctp_authkey_event *)
skb_put(skb, sizeof(struct sctp_authkey_event));
ak->auth_type = SCTP_AUTHENTICATION_EVENT;
ak->auth_flags = 0;
ak->auth_length = sizeof(struct sctp_authkey_event);
ak->auth_keynumber = key_id;
ak->auth_altkeynumber = 0;
ak->auth_indication = indication;
/*
* The association id field, holds the identifier for the association.
*/
sctp_ulpevent_set_owner(event, asoc);
ak->auth_assoc_id = sctp_assoc2id(asoc);
return event;
fail:
return NULL;
}
/*
* Socket Extensions for SCTP
* 6.3.10. SCTP_SENDER_DRY_EVENT
*/
struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
const struct sctp_association *asoc, gfp_t gfp)
{
struct sctp_ulpevent *event;
struct sctp_sender_dry_event *sdry;
struct sk_buff *skb;
event = sctp_ulpevent_new(sizeof(struct sctp_sender_dry_event),
MSG_NOTIFICATION, gfp);
if (!event)
return NULL;
skb = sctp_event2skb(event);
sdry = (struct sctp_sender_dry_event *)
skb_put(skb, sizeof(struct sctp_sender_dry_event));
sdry->sender_dry_type = SCTP_SENDER_DRY_EVENT;
sdry->sender_dry_flags = 0;
sdry->sender_dry_length = sizeof(struct sctp_sender_dry_event);
sctp_ulpevent_set_owner(event, asoc);
sdry->sender_dry_assoc_id = sctp_assoc2id(asoc);
return event;
}
/* Return the notification type, assuming this is a notification
* event.
*/
__u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
{
union sctp_notification *notification;
struct sk_buff *skb;
skb = sctp_event2skb(event);
notification = (union sctp_notification *) skb->data;
return notification->sn_header.sn_type;
}
/* RFC6458, Section 5.3.2. SCTP Header Information Structure
* (SCTP_SNDRCV, DEPRECATED)
*/
void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
struct msghdr *msghdr)
{
struct sctp_sndrcvinfo sinfo;
if (sctp_ulpevent_is_notification(event))
return;
memset(&sinfo, 0, sizeof(sinfo));
sinfo.sinfo_stream = event->stream;
sinfo.sinfo_ssn = event->ssn;
sinfo.sinfo_ppid = event->ppid;
sinfo.sinfo_flags = event->flags;
sinfo.sinfo_tsn = event->tsn;
sinfo.sinfo_cumtsn = event->cumtsn;
sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc);
/* Context value that is set via SCTP_CONTEXT socket option. */
sinfo.sinfo_context = event->asoc->default_rcv_context;
/* These fields are not used while receiving. */
sinfo.sinfo_timetolive = 0;
put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV,
sizeof(sinfo), &sinfo);
}
/* RFC6458, Section 5.3.5 SCTP Receive Information Structure
* (SCTP_SNDRCV)
*/
void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
struct msghdr *msghdr)
{
struct sctp_rcvinfo rinfo;
if (sctp_ulpevent_is_notification(event))
return;
memset(&rinfo, 0, sizeof(struct sctp_rcvinfo));
rinfo.rcv_sid = event->stream;
rinfo.rcv_ssn = event->ssn;
rinfo.rcv_ppid = event->ppid;
rinfo.rcv_flags = event->flags;
rinfo.rcv_tsn = event->tsn;
rinfo.rcv_cumtsn = event->cumtsn;
rinfo.rcv_assoc_id = sctp_assoc2id(event->asoc);
rinfo.rcv_context = event->asoc->default_rcv_context;
put_cmsg(msghdr, IPPROTO_SCTP, SCTP_RCVINFO,
sizeof(rinfo), &rinfo);
}
/* RFC6458, Section 5.3.6. SCTP Next Receive Information Structure
* (SCTP_NXTINFO)
*/
static void __sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
struct msghdr *msghdr,
const struct sk_buff *skb)
{
struct sctp_nxtinfo nxtinfo;
memset(&nxtinfo, 0, sizeof(nxtinfo));
nxtinfo.nxt_sid = event->stream;
nxtinfo.nxt_ppid = event->ppid;
nxtinfo.nxt_flags = event->flags;
if (sctp_ulpevent_is_notification(event))
nxtinfo.nxt_flags |= SCTP_NOTIFICATION;
nxtinfo.nxt_length = skb->len;
nxtinfo.nxt_assoc_id = sctp_assoc2id(event->asoc);
put_cmsg(msghdr, IPPROTO_SCTP, SCTP_NXTINFO,
sizeof(nxtinfo), &nxtinfo);
}
void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
struct msghdr *msghdr,
struct sock *sk)
{
struct sk_buff *skb;
int err;
skb = sctp_skb_recv_datagram(sk, MSG_PEEK, 1, &err);
if (skb != NULL) {
__sctp_ulpevent_read_nxtinfo(sctp_skb2event(skb),
msghdr, skb);
/* Just release refcount here. */
kfree_skb(skb);
}
}
/* Do accounting for bytes received and hold a reference to the association
* for each skb.
*/
static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
struct sctp_association *asoc)
{
struct sk_buff *skb, *frag;
skb = sctp_event2skb(event);
/* Set the owner and charge rwnd for bytes received. */
sctp_ulpevent_set_owner(event, asoc);
sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb));
if (!skb->data_len)
return;
/* Note: Not clearing the entire event struct as this is just a
* fragment of the real event. However, we still need to do rwnd
* accounting.
* In general, the skb passed from IP can have only 1 level of
* fragments. But we allow multiple levels of fragments.
*/
skb_walk_frags(skb, frag)
sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc);
}
/* Do accounting for bytes just read by user and release the references to
* the association.
*/
static void sctp_ulpevent_release_data(struct sctp_ulpevent *event)
{
struct sk_buff *skb, *frag;
unsigned int len;
/* Current stack structures assume that the rcv buffer is
* per socket. For UDP style sockets this is not true as
* multiple associations may be on a single UDP-style socket.
* Use the local private area of the skb to track the owning
* association.
*/
skb = sctp_event2skb(event);
len = skb->len;
if (!skb->data_len)
goto done;
/* Don't forget the fragments. */
skb_walk_frags(skb, frag) {
/* NOTE: skb_shinfos are recursive. Although IP returns
* skb's with only 1 level of fragments, SCTP reassembly can
* increase the levels.
*/
sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
}
done:
sctp_assoc_rwnd_increase(event->asoc, len);
sctp_ulpevent_release_owner(event);
}
static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event)
{
struct sk_buff *skb, *frag;
skb = sctp_event2skb(event);
if (!skb->data_len)
goto done;
/* Don't forget the fragments. */
skb_walk_frags(skb, frag) {
/* NOTE: skb_shinfos are recursive. Although IP returns
* skb's with only 1 level of fragments, SCTP reassembly can
* increase the levels.
*/
sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
}
done:
sctp_ulpevent_release_owner(event);
}
/* Free a ulpevent that has an owner. It includes releasing the reference
* to the owner, updating the rwnd in case of a DATA event and freeing the
* skb.
*/
void sctp_ulpevent_free(struct sctp_ulpevent *event)
{
if (sctp_ulpevent_is_notification(event))
sctp_ulpevent_release_owner(event);
else
sctp_ulpevent_release_data(event);
kfree_skb(sctp_event2skb(event));
}
/* Purge the skb lists holding ulpevents. */
unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list)
{
struct sk_buff *skb;
unsigned int data_unread = 0;
while ((skb = skb_dequeue(list)) != NULL) {
struct sctp_ulpevent *event = sctp_skb2event(skb);
if (!sctp_ulpevent_is_notification(event))
data_unread += skb->len;
sctp_ulpevent_free(event);
}
return data_unread;
}