[linux-2.6-block.git] / net / sctp / chunk.c

/* SCTP kernel implementation
 * (C) Copyright IBM Corp. 2003, 2004
 *
 * This file is part of the SCTP kernel implementation
 *
 * This file contains the code relating the chunk abstraction.
 *
 * 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>
 *    Sridhar Samudrala     <sri@us.ibm.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/net.h>
#include <linux/inet.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>

/* This file is mostly in anticipation of future work, but initially
 * populate with fragment tracking for an outbound message.
 */

/* Initialize datamsg from memory. */
static void sctp_datamsg_init(struct sctp_datamsg *msg)
{
	refcount_set(&msg->refcnt, 1);
	msg->send_failed = 0;
	msg->send_error = 0;
	msg->can_delay = 1;
	msg->abandoned = 0;
	msg->expires_at = 0;
	INIT_LIST_HEAD(&msg->chunks);
}

/* Allocate and initialize datamsg. */
static struct sctp_datamsg *sctp_datamsg_new(gfp_t gfp)
{
	struct sctp_datamsg *msg;
	msg = kmalloc(sizeof(struct sctp_datamsg), gfp);
	if (msg) {
		sctp_datamsg_init(msg);
		SCTP_DBG_OBJCNT_INC(datamsg);
	}
	return msg;
}

void sctp_datamsg_free(struct sctp_datamsg *msg)
{
	struct sctp_chunk *chunk;

	/* This doesn't have to be a _safe vairant because
	 * sctp_chunk_free() only drops the refs.
	 */
	list_for_each_entry(chunk, &msg->chunks, frag_list)
		sctp_chunk_free(chunk);

	sctp_datamsg_put(msg);
}

/* Final destructruction of datamsg memory. */
static void sctp_datamsg_destroy(struct sctp_datamsg *msg)
{
	struct sctp_association *asoc = NULL;
	struct list_head *pos, *temp;
	struct sctp_chunk *chunk;
	struct sctp_ulpevent *ev;
	int error = 0, notify;

	/* If we failed, we may need to notify. */
	notify = msg->send_failed ? -1 : 0;

	/* Release all references. */
	list_for_each_safe(pos, temp, &msg->chunks) {
		list_del_init(pos);
		chunk = list_entry(pos, struct sctp_chunk, frag_list);
		/* Check whether we _really_ need to notify. */
		if (notify < 0) {
			asoc = chunk->asoc;
			if (msg->send_error)
				error = msg->send_error;
			else
				error = asoc->outqueue.error;

			notify = sctp_ulpevent_type_enabled(asoc->subscribe,
							    SCTP_SEND_FAILED);
		}

		/* Generate a SEND FAILED event only if enabled. */
		if (notify > 0) {
			int sent;
			if (chunk->has_tsn)
				sent = SCTP_DATA_SENT;
			else
				sent = SCTP_DATA_UNSENT;

			ev = sctp_ulpevent_make_send_failed(asoc, chunk, sent,
							    error, GFP_ATOMIC);
			if (ev)
				asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
		}

		sctp_chunk_put(chunk);
	}

	SCTP_DBG_OBJCNT_DEC(datamsg);
	kfree(msg);
}

/* Hold a reference. */
static void sctp_datamsg_hold(struct sctp_datamsg *msg)
{
	refcount_inc(&msg->refcnt);
}

/* Release a reference. */
void sctp_datamsg_put(struct sctp_datamsg *msg)
{
	if (refcount_dec_and_test(&msg->refcnt))
		sctp_datamsg_destroy(msg);
}

/* Assign a chunk to this datamsg. */
static void sctp_datamsg_assign(struct sctp_datamsg *msg, struct sctp_chunk *chunk)
{
	sctp_datamsg_hold(msg);
	chunk->msg = msg;
}


/* A data chunk can have a maximum payload of (2^16 - 20).  Break
 * down any such message into smaller chunks.  Opportunistically, fragment
 * the chunks down to the current MTU constraints.  We may get refragmented
 * later if the PMTU changes, but it is _much better_ to fragment immediately
 * with a reasonable guess than always doing our fragmentation on the
 * soft-interrupt.
 */
struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
					    struct sctp_sndrcvinfo *sinfo,
					    struct iov_iter *from)
{
	size_t len, first_len, max_data, remaining;
	size_t msg_len = iov_iter_count(from);
	struct sctp_shared_key *shkey = NULL;
	struct list_head *pos, *temp;
	struct sctp_chunk *chunk;
	struct sctp_datamsg *msg;
	int err;

	msg = sctp_datamsg_new(GFP_KERNEL);
	if (!msg)
		return ERR_PTR(-ENOMEM);

	/* Note: Calculate this outside of the loop, so that all fragments
	 * have the same expiration.
	 */
	if (asoc->peer.prsctp_capable && sinfo->sinfo_timetolive &&
	    (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags) ||
	     !SCTP_PR_POLICY(sinfo->sinfo_flags)))
		msg->expires_at = jiffies +
				  msecs_to_jiffies(sinfo->sinfo_timetolive);

	/* This is the biggest possible DATA chunk that can fit into
	 * the packet
	 */
	max_data = asoc->frag_point;
	if (unlikely(!max_data)) {
		max_data = sctp_min_frag_point(sctp_sk(asoc->base.sk),
					       sctp_datachk_len(&asoc->stream));
		pr_warn_ratelimited("%s: asoc:%p frag_point is zero, forcing max_data to default minimum (%zu)",
				    __func__, asoc, max_data);
	}

	/* If the the peer requested that we authenticate DATA chunks
	 * we need to account for bundling of the AUTH chunks along with
	 * DATA.
	 */
	if (sctp_auth_send_cid(SCTP_CID_DATA, asoc)) {
		struct sctp_hmac *hmac_desc = sctp_auth_asoc_get_hmac(asoc);

		if (hmac_desc)
			max_data -= SCTP_PAD4(sizeof(struct sctp_auth_chunk) +
					      hmac_desc->hmac_len);

		if (sinfo->sinfo_tsn &&
		    sinfo->sinfo_ssn != asoc->active_key_id) {
			shkey = sctp_auth_get_shkey(asoc, sinfo->sinfo_ssn);
			if (!shkey) {
				err = -EINVAL;
				goto errout;
			}
		} else {
			shkey = asoc->shkey;
		}
	}

	/* Set first_len and then account for possible bundles on first frag */
	first_len = max_data;

	/* Check to see if we have a pending SACK and try to let it be bundled
	 * with this message.  Do this if we don't have any data queued already.
	 * To check that, look at out_qlen and retransmit list.
	 * NOTE: we will not reduce to account for SACK, if the message would
	 * not have been fragmented.
	 */
	if (timer_pending(&asoc->timers[SCTP_EVENT_TIMEOUT_SACK]) &&
	    asoc->outqueue.out_qlen == 0 &&
	    list_empty(&asoc->outqueue.retransmit) &&
	    msg_len > max_data)
		first_len -= SCTP_PAD4(sizeof(struct sctp_sack_chunk));

	/* Encourage Cookie-ECHO bundling. */
	if (asoc->state < SCTP_STATE_COOKIE_ECHOED)
		first_len -= SCTP_ARBITRARY_COOKIE_ECHO_LEN;

	/* Account for a different sized first fragment */
	if (msg_len >= first_len) {
		msg->can_delay = 0;
		if (msg_len > first_len)
			SCTP_INC_STATS(sock_net(asoc->base.sk),
				       SCTP_MIB_FRAGUSRMSGS);
	} else {
		/* Which may be the only one... */
		first_len = msg_len;
	}

	/* Create chunks for all DATA chunks. */
	for (remaining = msg_len; remaining; remaining -= len) {
		u8 frag = SCTP_DATA_MIDDLE_FRAG;

		if (remaining == msg_len) {
			/* First frag, which may also be the last */
			frag |= SCTP_DATA_FIRST_FRAG;
			len = first_len;
		} else {
			/* Middle frags */
			len = max_data;
		}

		if (len >= remaining) {
			/* Last frag, which may also be the first */
			len = remaining;
			frag |= SCTP_DATA_LAST_FRAG;

			/* The application requests to set the I-bit of the
			 * last DATA chunk of a user message when providing
			 * the user message to the SCTP implementation.
			 */
			if ((sinfo->sinfo_flags & SCTP_EOF) ||
			    (sinfo->sinfo_flags & SCTP_SACK_IMMEDIATELY))
				frag |= SCTP_DATA_SACK_IMM;
		}

		chunk = asoc->stream.si->make_datafrag(asoc, sinfo, len, frag,
						       GFP_KERNEL);
		if (!chunk) {
			err = -ENOMEM;
			goto errout;
		}

		err = sctp_user_addto_chunk(chunk, len, from);
		if (err < 0)
			goto errout_chunk_free;

		chunk->shkey = shkey;

		/* Put the chunk->skb back into the form expected by send.  */
		__skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr -
				       chunk->skb->data);

		sctp_datamsg_assign(msg, chunk);
		list_add_tail(&chunk->frag_list, &msg->chunks);
	}

	return msg;

errout_chunk_free:
	sctp_chunk_free(chunk);

errout:
	list_for_each_safe(pos, temp, &msg->chunks) {
		list_del_init(pos);
		chunk = list_entry(pos, struct sctp_chunk, frag_list);
		sctp_chunk_free(chunk);
	}
	sctp_datamsg_put(msg);

	return ERR_PTR(err);
}

/* Check whether this message has expired. */
int sctp_chunk_abandoned(struct sctp_chunk *chunk)
{
	if (!chunk->asoc->peer.prsctp_capable)
		return 0;

	if (chunk->msg->abandoned)
		return 1;

	if (!chunk->has_tsn &&
	    !(chunk->chunk_hdr->flags & SCTP_DATA_FIRST_FRAG))
		return 0;

	if (SCTP_PR_TTL_ENABLED(chunk->sinfo.sinfo_flags) &&
	    time_after(jiffies, chunk->msg->expires_at)) {
		struct sctp_stream_out *streamout =
			SCTP_SO(&chunk->asoc->stream,
				chunk->sinfo.sinfo_stream);

		if (chunk->sent_count) {
			chunk->asoc->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
			streamout->ext->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
		} else {
			chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
			streamout->ext->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
		}
		chunk->msg->abandoned = 1;
		return 1;
	} else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&
		   chunk->sent_count > chunk->sinfo.sinfo_timetolive) {
		struct sctp_stream_out *streamout =
			SCTP_SO(&chunk->asoc->stream,
				chunk->sinfo.sinfo_stream);

		chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
		streamout->ext->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
		chunk->msg->abandoned = 1;
		return 1;
	} else if (!SCTP_PR_POLICY(chunk->sinfo.sinfo_flags) &&
		   chunk->msg->expires_at &&
		   time_after(jiffies, chunk->msg->expires_at)) {
		chunk->msg->abandoned = 1;
		return 1;
	}
	/* PRIO policy is processed by sendmsg, not here */

	return 0;
}

/* This chunk (and consequently entire message) has failed in its sending. */
void sctp_chunk_fail(struct sctp_chunk *chunk, int error)
{
	chunk->msg->send_failed = 1;
	chunk->msg->send_error = error;
}
Commit	Line	Data
60c778b2	1	/* SCTP kernel implementation
1da177e4 LT	2	* (C) Copyright IBM Corp. 2003, 2004
1da177e4 LT	3	*
60c778b2	4	* This file is part of the SCTP kernel implementation
1da177e4	5	*
59c51591	6	* This file contains the code relating the chunk abstraction.
1da177e4	7	*
60c778b2	8	* This SCTP implementation is free software;
1da177e4 LT	9	* you can redistribute it and/or modify it under the terms of
	10	* the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2, or (at your option)
	12	* any later version.
	13	*
60c778b2	14	* This SCTP implementation is distributed in the hope that it
1da177e4 LT	15	* will be useful, but WITHOUT ANY WARRANTY; without even the implied
	16	* ************************
	17	* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
	18	* See the GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
4b2f13a2 JK	21	* along with GNU CC; see the file COPYING. If not, see
4b2f13a2 JK	22	* <http://www.gnu.org/licenses/>.
1da177e4 LT	23	*
	24	* Please send any bug reports or fixes you make to the
	25	* email address(es):
91705c61	26	* lksctp developers <linux-sctp@vger.kernel.org>
1da177e4	27	*
1da177e4 LT	28	* Written or modified by:
	29	* Jon Grimm <jgrimm@us.ibm.com>
	30	* Sridhar Samudrala <sri@us.ibm.com>
1da177e4 LT	31	*/
1da177e4 LT	32
145ce502 JP	33	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
145ce502 JP	34
1da177e4 LT	35	#include <linux/types.h>
	36	#include <linux/kernel.h>
	37	#include <linux/net.h>
	38	#include <linux/inet.h>
	39	#include <linux/skbuff.h>
5a0e3ad6	40	#include <linux/slab.h>
1da177e4 LT	41	#include <net/sock.h>
	42	#include <net/sctp/sctp.h>
	43	#include <net/sctp/sm.h>
	44
	45	/* This file is mostly in anticipation of future work, but initially
	46	* populate with fragment tracking for an outbound message.
	47	*/
	48
	49	/* Initialize datamsg from memory. */
	50	static void sctp_datamsg_init(struct sctp_datamsg *msg)
	51	{
c0acdfb4	52	refcount_set(&msg->refcnt, 1);
1da177e4 LT	53	msg->send_failed = 0;
1da177e4 LT	54	msg->send_error = 0;
0e3aef8d	55	msg->can_delay = 1;
e5f61296	56	msg->abandoned = 0;
1da177e4 LT	57	msg->expires_at = 0;
	58	INIT_LIST_HEAD(&msg->chunks);
	59	}
	60
	61	/* Allocate and initialize datamsg. */
dda91928	62	static struct sctp_datamsg *sctp_datamsg_new(gfp_t gfp)
1da177e4 LT	63	{
	64	struct sctp_datamsg *msg;
	65	msg = kmalloc(sizeof(struct sctp_datamsg), gfp);
e8c38751	66	if (msg) {
1da177e4	67	sctp_datamsg_init(msg);
e8c38751 LZ	68	SCTP_DBG_OBJCNT_INC(datamsg);
e8c38751 LZ	69	}
1da177e4 LT	70	return msg;
	71	}
	72
b61c654f XL	73	void sctp_datamsg_free(struct sctp_datamsg *msg)
	74	{
	75	struct sctp_chunk *chunk;
	76
	77	/* This doesn't have to be a _safe vairant because
	78	* sctp_chunk_free() only drops the refs.
	79	*/
	80	list_for_each_entry(chunk, &msg->chunks, frag_list)
	81	sctp_chunk_free(chunk);
	82
	83	sctp_datamsg_put(msg);
	84	}
	85
1da177e4 LT	86	/* Final destructruction of datamsg memory. */
	87	static void sctp_datamsg_destroy(struct sctp_datamsg *msg)
	88	{
a1e3a059	89	struct sctp_association *asoc = NULL;
1da177e4 LT	90	struct list_head pos, temp;
1da177e4 LT	91	struct sctp_chunk *chunk;
1da177e4	92	struct sctp_ulpevent *ev;
1da177e4 LT	93	int error = 0, notify;
	94
	95	/* If we failed, we may need to notify. */
	96	notify = msg->send_failed ? -1 : 0;
	97
	98	/* Release all references. */
	99	list_for_each_safe(pos, temp, &msg->chunks) {
	100	list_del_init(pos);
	101	chunk = list_entry(pos, struct sctp_chunk, frag_list);
	102	/* Check whether we _really_ need to notify. */
	103	if (notify < 0) {
	104	asoc = chunk->asoc;
	105	if (msg->send_error)
	106	error = msg->send_error;
	107	else
	108	error = asoc->outqueue.error;
	109
a1e3a059	110	notify = sctp_ulpevent_type_enabled(asoc->subscribe,
2cc0eeb6	111	SCTP_SEND_FAILED);
1da177e4 LT	112	}
	113
	114	/* Generate a SEND FAILED event only if enabled. */
	115	if (notify > 0) {
	116	int sent;
	117	if (chunk->has_tsn)
	118	sent = SCTP_DATA_SENT;
	119	else
	120	sent = SCTP_DATA_UNSENT;
	121
	122	ev = sctp_ulpevent_make_send_failed(asoc, chunk, sent,
	123	error, GFP_ATOMIC);
	124	if (ev)
9162e0ed	125	asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1da177e4 LT	126	}
	127
	128	sctp_chunk_put(chunk);
	129	}
	130
	131	SCTP_DBG_OBJCNT_DEC(datamsg);
	132	kfree(msg);
	133	}
	134
	135	/* Hold a reference. */
	136	static void sctp_datamsg_hold(struct sctp_datamsg *msg)
	137	{
c0acdfb4	138	refcount_inc(&msg->refcnt);
1da177e4 LT	139	}
	140
	141	/* Release a reference. */
	142	void sctp_datamsg_put(struct sctp_datamsg *msg)
	143	{
c0acdfb4	144	if (refcount_dec_and_test(&msg->refcnt))
1da177e4 LT	145	sctp_datamsg_destroy(msg);
	146	}
	147
1da177e4 LT	148	/* Assign a chunk to this datamsg. */
	149	static void sctp_datamsg_assign(struct sctp_datamsg msg, struct sctp_chunk chunk)
	150	{
	151	sctp_datamsg_hold(msg);
	152	chunk->msg = msg;
	153	}
	154
	155
	156	/* A data chunk can have a maximum payload of (2^16 - 20). Break
	157	* down any such message into smaller chunks. Opportunistically, fragment
	158	* the chunks down to the current MTU constraints. We may get refragmented
	159	* later if the PMTU changes, but it is _much better_ to fragment immediately
	160	* with a reasonable guess than always doing our fragmentation on the
	161	* soft-interrupt.
	162	*/
	163	struct sctp_datamsg sctp_datamsg_from_user(struct sctp_association asoc,
	164	struct sctp_sndrcvinfo *sinfo,
e0eb093e	165	struct iov_iter *from)
1da177e4	166	{
bfd2e4b8 MRL	167	size_t len, first_len, max_data, remaining;
bfd2e4b8 MRL	168	size_t msg_len = iov_iter_count(from);
1b1e0bc9	169	struct sctp_shared_key *shkey = NULL;
bfd2e4b8	170	struct list_head pos, temp;
1da177e4 LT	171	struct sctp_chunk *chunk;
1da177e4 LT	172	struct sctp_datamsg *msg;
bfd2e4b8	173	int err;
1da177e4 LT	174
	175	msg = sctp_datamsg_new(GFP_KERNEL);
	176	if (!msg)
6e51fe75	177	return ERR_PTR(-ENOMEM);
1da177e4 LT	178
	179	/* Note: Calculate this outside of the loop, so that all fragments
	180	* have the same expiration.
	181	*/
8ae808eb XL	182	if (asoc->peer.prsctp_capable && sinfo->sinfo_timetolive &&
	183	(SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags) \|\|
	184	!SCTP_PR_POLICY(sinfo->sinfo_flags)))
1da177e4	185	msg->expires_at = jiffies +
bfd2e4b8	186	msecs_to_jiffies(sinfo->sinfo_timetolive);
0605483f	187
3e62abf9 VY	188	/* This is the biggest possible DATA chunk that can fit into
	189	* the packet
	190	*/
2f5e3c9d	191	max_data = asoc->frag_point;
afd0a800 JA	192	if (unlikely(!max_data)) {
	193	max_data = sctp_min_frag_point(sctp_sk(asoc->base.sk),
	194	sctp_datachk_len(&asoc->stream));
ac510505	195	pr_warn_ratelimited("%s: asoc:%p frag_point is zero, forcing max_data to default minimum (%zu)",
afd0a800 JA	196	__func__, asoc, max_data);
afd0a800 JA	197	}
1da177e4	198
4cd57c80	199	/* If the the peer requested that we authenticate DATA chunks
2bccbadf	200	* we need to account for bundling of the AUTH chunks along with
4cd57c80 VY	201	* DATA.
	202	*/
	203	if (sctp_auth_send_cid(SCTP_CID_DATA, asoc)) {
	204	struct sctp_hmac *hmac_desc = sctp_auth_asoc_get_hmac(asoc);
	205
	206	if (hmac_desc)
bb96dec7	207	max_data -= SCTP_PAD4(sizeof(struct sctp_auth_chunk) +
e2f036a9	208	hmac_desc->hmac_len);
1b1e0bc9	209
3ff547c0 XL	210	if (sinfo->sinfo_tsn &&
	211	sinfo->sinfo_ssn != asoc->active_key_id) {
	212	shkey = sctp_auth_get_shkey(asoc, sinfo->sinfo_ssn);
	213	if (!shkey) {
	214	err = -EINVAL;
	215	goto errout;
	216	}
	217	} else {
	218	shkey = asoc->shkey;
	219	}
4cd57c80 VY	220	}
4cd57c80 VY	221
bfd2e4b8 MRL	222	/* Set first_len and then account for possible bundles on first frag */
bfd2e4b8 MRL	223	first_len = max_data;
1da177e4	224
5d7ff261 VY	225	/* Check to see if we have a pending SACK and try to let it be bundled
	226	* with this message. Do this if we don't have any data queued already.
	227	* To check that, look at out_qlen and retransmit list.
	228	* NOTE: we will not reduce to account for SACK, if the message would
	229	* not have been fragmented.
	230	*/
	231	if (timer_pending(&asoc->timers[SCTP_EVENT_TIMEOUT_SACK]) &&
	232	asoc->outqueue.out_qlen == 0 &&
	233	list_empty(&asoc->outqueue.retransmit) &&
bfd2e4b8	234	msg_len > max_data)
d4d6c614	235	first_len -= SCTP_PAD4(sizeof(struct sctp_sack_chunk));
5d7ff261	236
1da177e4	237	/* Encourage Cookie-ECHO bundling. */
5d7ff261	238	if (asoc->state < SCTP_STATE_COOKIE_ECHOED)
bfd2e4b8	239	first_len -= SCTP_ARBITRARY_COOKIE_ECHO_LEN;
3e62abf9 VY	240
	241	/* Account for a different sized first fragment */
	242	if (msg_len >= first_len) {
0e3aef8d	243	msg->can_delay = 0;
fedb1bd3 MRL	244	if (msg_len > first_len)
	245	SCTP_INC_STATS(sock_net(asoc->base.sk),
	246	SCTP_MIB_FRAGUSRMSGS);
bfd2e4b8 MRL	247	} else {
	248	/* Which may be the only one... */
	249	first_len = msg_len;
	250	}
1da177e4	251
bfd2e4b8 MRL	252	/* Create chunks for all DATA chunks. */
	253	for (remaining = msg_len; remaining; remaining -= len) {
	254	u8 frag = SCTP_DATA_MIDDLE_FRAG;
1da177e4	255
bfd2e4b8 MRL	256	if (remaining == msg_len) {
bfd2e4b8 MRL	257	/* First frag, which may also be the last */
1da177e4	258	frag \|= SCTP_DATA_FIRST_FRAG;
bfd2e4b8 MRL	259	len = first_len;
	260	} else {
	261	/* Middle frags */
	262	len = max_data;
	263	}
1da177e4	264
bfd2e4b8 MRL	265	if (len >= remaining) {
	266	/* Last frag, which may also be the first */
	267	len = remaining;
1da177e4 LT	268	frag \|= SCTP_DATA_LAST_FRAG;
1da177e4 LT	269
b93d6471 WY	270	/* The application requests to set the I-bit of the
	271	* last DATA chunk of a user message when providing
	272	* the user message to the SCTP implementation.
	273	*/
	274	if ((sinfo->sinfo_flags & SCTP_EOF) \|\|
	275	(sinfo->sinfo_flags & SCTP_SACK_IMMEDIATELY))
	276	frag \|= SCTP_DATA_SACK_IMM;
	277	}
	278
0c3f6f65 XL	279	chunk = asoc->stream.si->make_datafrag(asoc, sinfo, len, frag,
0c3f6f65 XL	280	GFP_KERNEL);
6e51fe75 TR	281	if (!chunk) {
6e51fe75 TR	282	err = -ENOMEM;
1da177e4	283	goto errout;
6e51fe75 TR	284	}
6e51fe75 TR	285
e0eb093e	286	err = sctp_user_addto_chunk(chunk, len, from);
1da177e4	287	if (err < 0)
be364c8c	288	goto errout_chunk_free;
1da177e4	289
1b1e0bc9 XL	290	chunk->shkey = shkey;
1b1e0bc9 XL	291
1da177e4	292	/* Put the chunk->skb back into the form expected by send. */
bfd2e4b8 MRL	293	__skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr -
bfd2e4b8 MRL	294	chunk->skb->data);
1da177e4 LT	295
	296	sctp_datamsg_assign(msg, chunk);
	297	list_add_tail(&chunk->frag_list, &msg->chunks);
	298	}
	299
	300	return msg;
	301
be364c8c TR	302	errout_chunk_free:
	303	sctp_chunk_free(chunk);
	304
1da177e4 LT	305	errout:
	306	list_for_each_safe(pos, temp, &msg->chunks) {
	307	list_del_init(pos);
	308	chunk = list_entry(pos, struct sctp_chunk, frag_list);
	309	sctp_chunk_free(chunk);
	310	}
80445cfb	311	sctp_datamsg_put(msg);
bfd2e4b8	312
6e51fe75	313	return ERR_PTR(err);
1da177e4 LT	314	}
	315
	316	/* Check whether this message has expired. */
	317	int sctp_chunk_abandoned(struct sctp_chunk *chunk)
	318	{
8ae808eb	319	if (!chunk->asoc->peer.prsctp_capable)
1da177e4 LT	320	return 0;
1da177e4 LT	321
e5f61296 XL	322	if (chunk->msg->abandoned)
	323	return 1;
	324
779edd73 XL	325	if (!chunk->has_tsn &&
	326	!(chunk->chunk_hdr->flags & SCTP_DATA_FIRST_FRAG))
	327	return 0;
	328
a6c2f792	329	if (SCTP_PR_TTL_ENABLED(chunk->sinfo.sinfo_flags) &&
0605483f	330	time_after(jiffies, chunk->msg->expires_at)) {
d229d48d	331	struct sctp_stream_out *streamout =
05364ca0 KK	332	SCTP_SO(&chunk->asoc->stream,
05364ca0 KK	333	chunk->sinfo.sinfo_stream);
d229d48d XL	334
d229d48d XL	335	if (chunk->sent_count) {
a6c2f792	336	chunk->asoc->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
f952be79	337	streamout->ext->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
d229d48d	338	} else {
a6c2f792	339	chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
f952be79	340	streamout->ext->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
d229d48d	341	}
e5f61296	342	chunk->msg->abandoned = 1;
1da177e4	343	return 1;
01aadb3a	344	} else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&
0605483f	345	chunk->sent_count > chunk->sinfo.sinfo_timetolive) {
d229d48d	346	struct sctp_stream_out *streamout =
05364ca0 KK	347	SCTP_SO(&chunk->asoc->stream,
05364ca0 KK	348	chunk->sinfo.sinfo_stream);
d229d48d	349
01aadb3a	350	chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
f952be79	351	streamout->ext->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
e5f61296	352	chunk->msg->abandoned = 1;
01aadb3a	353	return 1;
8ae808eb XL	354	} else if (!SCTP_PR_POLICY(chunk->sinfo.sinfo_flags) &&
	355	chunk->msg->expires_at &&
	356	time_after(jiffies, chunk->msg->expires_at)) {
e5f61296	357	chunk->msg->abandoned = 1;
8ae808eb	358	return 1;
a6c2f792	359	}
8dbdf1f5	360	/* PRIO policy is processed by sendmsg, not here */
1da177e4 LT	361
	362	return 0;
	363	}
	364
	365	/* This chunk (and consequently entire message) has failed in its sending. */
	366	void sctp_chunk_fail(struct sctp_chunk *chunk, int error)
	367	{
	368	chunk->msg->send_failed = 1;
	369	chunk->msg->send_error = error;
	370	}