[SCTP]: Rename sctp_foo.[ch] to foo.[ch] and kill CVS tags on authors request.

1 files changed, 476 insertions, 0 deletions

diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c
new file mode 100644
index 000000000000..f2011e0127eb
--- /dev/null
+++ b/net/sctp/ulpqueue.c
@@ -0,0 +1,476 @@
+/* SCTP kernel reference Implementation
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001-2002 International Business Machines, Corp.
+ * Copyright (c) 2001 Intel Corp.
+ * Copyright (c) 2001 Nokia, Inc.
+ * Copyright (c) 2001 La Monte H.P. Yarroll
+ * 
+ * This abstraction carries sctp events to the ULP (sockets).
+ * 
+ * The SCTP reference 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.
+ * 
+ * The SCTP reference 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, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.  
+ * 
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <lksctp-developers@lists.sourceforge.net>
+ * 
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by: 
+ *    Jon Grimm             <jgrimm@us.ibm.com>
+ *    La Monte H.P. Yarroll <piggy@acm.org>
+ *    Sridhar Samudrala     <sri@us.ibm.com>
+ * 
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/sctp/structs.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+/* Forward declarations for internal helpers.  */
+static inline sctp_ulpevent_t * sctp_ulpqueue_reasm(sctp_ulpqueue_t *ulpq,
+						    sctp_ulpevent_t *event);
+static inline sctp_ulpevent_t *sctp_ulpqueue_order(sctp_ulpqueue_t *ulpq,
+						   sctp_ulpevent_t *event);
+
+/* 1st Level Abstractions */
+
+/* Create a new ULP queue.  */
+sctp_ulpqueue_t *sctp_ulpqueue_new(sctp_association_t *asoc,
+				   __u16 inbound, int priority)
+{
+	sctp_ulpqueue_t *ulpq;
+	size_t size;
+
+	/* Today, there is only a fixed size of storage needed for
+	 * stream support, but make the interfaces acceptable for
+	 * the future.
+	 */
+	size = sizeof(sctp_ulpqueue_t)+sctp_ulpqueue_storage_size(inbound);
+	ulpq = kmalloc(size, priority);
+	if (!ulpq)
+		goto fail;
+	if (!sctp_ulpqueue_init(ulpq, asoc, inbound))
+		goto fail_init;
+	ulpq->malloced = 1;
+	return ulpq;
+
+fail_init:
+	kfree(ulpq);
+
+fail:
+	return NULL;
+}
+
+/* Initialize a ULP queue from a block of memory.  */
+sctp_ulpqueue_t *sctp_ulpqueue_init(sctp_ulpqueue_t *ulpq,
+				    sctp_association_t *asoc,
+				    __u16 inbound)
+{
+	memset(ulpq,
+	       sizeof(sctp_ulpqueue_t) + sctp_ulpqueue_storage_size(inbound),
+	       0x00);
+
+	ulpq->asoc = asoc;
+	spin_lock_init(&ulpq->lock);
+	skb_queue_head_init(&ulpq->reasm);
+	skb_queue_head_init(&ulpq->lobby);
+	ulpq->malloced = 0;
+
+	return ulpq;
+}
+
+/* Flush the reassembly and ordering queues.  */
+void sctp_ulpqueue_flush(sctp_ulpqueue_t *ulpq)
+{
+	struct sk_buff *skb;
+	sctp_ulpevent_t *event;
+
+	while ((skb = skb_dequeue(&ulpq->lobby))) {
+		event = (sctp_ulpevent_t *) skb->cb;
+		sctp_ulpevent_free(event);
+	}
+
+	while ((skb = skb_dequeue(&ulpq->reasm))) {
+		event = (sctp_ulpevent_t *) skb->cb;
+		sctp_ulpevent_free(event);
+	}
+}
+
+/* Dispose of a ulpqueue.  */
+void sctp_ulpqueue_free(sctp_ulpqueue_t *ulpq)
+{
+	sctp_ulpqueue_flush(ulpq);
+	if (ulpq->malloced)
+		kfree(ulpq);
+}
+
+/* Process an incoming DATA chunk.  */
+int sctp_ulpqueue_tail_data(sctp_ulpqueue_t *ulpq, sctp_chunk_t *chunk,
+			    int priority)
+{
+	struct sk_buff_head temp;
+	sctp_data_chunk_t *hdr;	
+	sctp_ulpevent_t *event;
+
+	hdr = (sctp_data_chunk_t *) chunk->chunk_hdr;
+
+	/* FIXME: Instead of event being the skb clone, we really should
+	 * have a new skb based chunk structure that we can convert to
+	 * an event.  Temporarily, I'm carrying a few chunk fields in
+	 * the event to allow reassembly.  Its too painful to change
+	 * everything at once.  --jgrimm
+	 */
+	event = sctp_ulpevent_make_rcvmsg(chunk->asoc, chunk, priority);
+	if (!event)
+		return -ENOMEM;
+
+	/* Do reassembly if needed.  */
+	event = sctp_ulpqueue_reasm(ulpq, event);
+
+	/* Do ordering if needed.  */
+	if (event) {
+		/* Create a temporary list to collect chunks on.  */
+		skb_queue_head_init(&temp);
+		skb_queue_tail(&temp, event->parent);
+
+		event = sctp_ulpqueue_order(ulpq, event);
+	}
+	
+	/* Send event to the ULP.  */
+	if (event)
+		sctp_ulpqueue_tail_event(ulpq, event);
+
+	return 0;
+}
+
+/* Add a new event for propogation to the ULP.  */
+int sctp_ulpqueue_tail_event(sctp_ulpqueue_t *ulpq, sctp_ulpevent_t *event)
+{
+	struct sock *sk = ulpq->asoc->base.sk;
+
+	/* If the socket is just going to throw this away, do not
+	 * even try to deliver it.
+	 */
+	if (sk->dead || (sk->shutdown & RCV_SHUTDOWN))
+		goto out_free;
+
+	/* Check if the user wishes to receive this event.  */
+	if (!sctp_ulpevent_is_enabled(event, &sctp_sk(sk)->subscribe))
+		goto out_free;
+
+	/* If we are harvesting multiple skbs they will be
+	 * collected on a list.
+	 */
+	if (event->parent->list)
+		sctp_skb_list_tail(event->parent->list, &sk->receive_queue);
+	else
+		skb_queue_tail(&sk->receive_queue, event->parent);
+
+	wake_up_interruptible(sk->sleep);
+	return 1;
+
+out_free:
+	if (event->parent->list)
+		skb_queue_purge(event->parent->list);
+	else
+		kfree_skb(event->parent);
+	return 0;
+}
+
+/* 2nd Level Abstractions */
+
+/* Helper function to store chunks that need to be reassembled.  */
+static inline void sctp_ulpqueue_store_reasm(sctp_ulpqueue_t *ulpq, sctp_ulpevent_t *event)
+{
+	struct sk_buff *pos, *tmp;
+	sctp_ulpevent_t *cevent;
+	__u32 tsn, ctsn;
+	unsigned long flags __attribute ((unused));
+
+	tsn = event->sndrcvinfo.sinfo_tsn;
+
+	sctp_spin_lock_irqsave(&ulpq->reasm.lock, flags);
+
+	/* Find the right place in this list. We store them by TSN.  */
+	sctp_skb_for_each(pos, &ulpq->reasm, tmp) {
+		cevent = (sctp_ulpevent_t *)pos->cb;
+		ctsn = cevent->sndrcvinfo.sinfo_tsn;
+
+		if (TSN_lt(tsn, ctsn))
+			break;
+	}
+
+	/* If the queue is empty, we have a different function to call.  */
+	if (skb_peek(&ulpq->reasm))
+		__skb_insert(event->parent, pos->prev, pos, &ulpq->reasm);
+	else
+		__skb_queue_tail(&ulpq->reasm, event->parent);
+
+	sctp_spin_unlock_irqrestore(&ulpq->reasm.lock, flags);
+}
+
+/* Helper function to return an event corresponding to the reassembled
+ * datagram.
+ */
+static inline sctp_ulpevent_t *sctp_make_reassembled_event(struct sk_buff *f_frag, struct sk_buff *l_frag)
+{
+	struct sk_buff *pos;
+	sctp_ulpevent_t *event;
+	struct sk_buff *pnext;
+
+	pos = f_frag->next;
+
+	/* Set the first fragment's frag_list to point to the 2nd fragment.  */
+	skb_shinfo(f_frag)->frag_list = pos;
+
+	/* Remove the first fragment from the reassembly queue.  */
+	__skb_unlink(f_frag, f_frag->list);
+	do {
+		pnext = pos->next;
+
+		/* Remove the fragment from the reassembly queue.  */
+		__skb_unlink(pos, pos->list);
+
+		/* Break if we have reached the last fragment.  */
+		if (pos == l_frag)
+			break;
+
+		pos->next = pnext;
+		pos = pnext;
+	} while (1);
+
+	event = (sctp_ulpevent_t *) f_frag->cb;
+
+	return event;
+}
+
+/* Helper function to check if an incoming chunk has filled up the last
+ * missing fragment in a SCTP datagram and return the corresponding event.
+ */
+static inline sctp_ulpevent_t *sctp_ulpqueue_retrieve_reassembled(sctp_ulpqueue_t *ulpq)
+{
+	struct sk_buff *pos, *tmp;
+	sctp_ulpevent_t *cevent;
+	struct sk_buff *first_frag = NULL;
+	__u32 ctsn, next_tsn;
+	unsigned long flags __attribute ((unused));
+	sctp_ulpevent_t *retval = NULL;
+
+	/* Initialized to 0 just to avoid compiler warning message. Will
+	 * never be used with this value. It is referenced only after it
+	 * is set when we find the first fragment of a message.
+	 */
+	next_tsn = 0;
+
+	sctp_spin_lock_irqsave(&ulpq->reasm.lock, flags);
+
+	/* The chunks are held in the reasm queue sorted by TSN.
+	 * Walk through the queue sequentially and look for a sequence of
+	 * fragmented chunks that complete a datagram.
+	 * 'first_frag' and next_tsn are reset when we find a chunk which
+	 * is the first fragment of a datagram. Once these 2 fields are set
+	 * we expect to find the remaining middle fragments and the last
+	 * fragment in order. If not, first_frag is reset to NULL and we
+	 * start the next pass when we find another first fragment.
+	 */
+	sctp_skb_for_each(pos, &ulpq->reasm, tmp) {
+		cevent = (sctp_ulpevent_t *) pos->cb;
+		ctsn = cevent->sndrcvinfo.sinfo_tsn;
+
+		switch (cevent->chunk_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			first_frag = pos;
+			next_tsn = ctsn + 1;
+			break;
+
+		case SCTP_DATA_MIDDLE_FRAG:
+			if ((first_frag) && (ctsn == next_tsn))
+				next_tsn++;
+			else
+				first_frag = NULL;
+			break;
+
+		case SCTP_DATA_LAST_FRAG:
+			if ((first_frag) && (ctsn == next_tsn))
+				retval = sctp_make_reassembled_event(
+						first_frag, pos);
+			else
+				first_frag = NULL;
+			break;
+		};
+
+		/* We have the reassembled event. There is no need to look
+		 * further.
+		 */
+		if (retval)
+			break;
+	}
+	sctp_spin_unlock_irqrestore(&ulpq->reasm.lock, flags);
+
+	return retval;
+}
+
+/* Helper function to reassemble chunks. Hold chunks on the reasm queue that
+ * need reassembling.
+ */
+static inline sctp_ulpevent_t *sctp_ulpqueue_reasm(sctp_ulpqueue_t *ulpq,
+						   sctp_ulpevent_t *event)
+{
+	sctp_ulpevent_t *retval = NULL;
+
+	/* FIXME: We should be using some new chunk structure here
+	 * instead of carrying chunk fields in the event structure.
+	 * This is temporary as it is too painful to change everything
+	 * at once.
+	 */
+
+	/* Check if this is part of a fragmented message.  */
+	if (SCTP_DATA_NOT_FRAG == (event->chunk_flags & SCTP_DATA_FRAG_MASK))
+		return event;
+
+	sctp_ulpqueue_store_reasm(ulpq, event);
+	retval = sctp_ulpqueue_retrieve_reassembled(ulpq);
+
+	return retval;
+}
+
+/* Helper function to gather skbs that have possibly become
+ * ordered by an an incoming chunk.
+ */
+static inline void sctp_ulpqueue_retrieve_ordered(sctp_ulpqueue_t *ulpq,
+						  sctp_ulpevent_t *event)
+{
+	struct sk_buff *pos, *tmp;
+	sctp_ulpevent_t *cevent;
+	__u16 sid, csid;
+	__u16 ssn, cssn;
+	unsigned long flags __attribute ((unused));
+
+	sid = event->sndrcvinfo.sinfo_stream;
+	ssn = event->sndrcvinfo.sinfo_ssn;
+
+	/* We are holding the chunks by stream, by SSN.  */
+	sctp_spin_lock_irqsave(&ulpq->lobby.lock, flags);
+	sctp_skb_for_each(pos, &ulpq->lobby, tmp) {
+		cevent = (sctp_ulpevent_t *) pos->cb;
+		csid = cevent->sndrcvinfo.sinfo_stream;
+		cssn = cevent->sndrcvinfo.sinfo_ssn;
+
+		/* Have we gone too far?  */
+		if (csid > sid)
+			break;
+
+		/* Have we not gone far enough?  */
+		if (csid < sid)
+			continue;
+
+		if (cssn != ulpq->ssn[sid])
+			break;
+
+		ulpq->ssn[sid]++;
+		__skb_unlink(pos, pos->list);
+
+		/* Attach all gathered skbs to the event.  */
+		__skb_queue_tail(event->parent->list, pos);
+	}
+	sctp_spin_unlock_irqrestore(&ulpq->lobby.lock, flags);
+}
+
+/* Helper function to store chunks needing ordering.  */
+static inline void sctp_ulpqueue_store_ordered(sctp_ulpqueue_t *ulpq,
+					       sctp_ulpevent_t *event)
+{
+	struct sk_buff *pos, *tmp;
+	sctp_ulpevent_t *cevent;
+	__u16 sid, csid;
+	__u16 ssn, cssn;
+	unsigned long flags __attribute ((unused));
+
+	sid = event->sndrcvinfo.sinfo_stream;
+	ssn = event->sndrcvinfo.sinfo_ssn;
+
+	sctp_spin_lock_irqsave(&ulpq->lobby.lock, flags);
+
+	/* Find the right place in this list.  We store them by
+	 * stream ID and then by SSN.
+	 */
+	sctp_skb_for_each(pos, &ulpq->lobby, tmp) {
+		cevent = (sctp_ulpevent_t *) pos->cb;
+		csid = cevent->sndrcvinfo.sinfo_stream;
+		cssn = cevent->sndrcvinfo.sinfo_ssn;
+
+		if (csid > sid)
+			break;
+		if (csid == sid && SSN_lt(ssn, cssn))
+			break;
+	}
+
+	/* If the queue is empty, we have a different function to call.  */
+	if (skb_peek(&ulpq->lobby))
+		__skb_insert(event->parent, pos->prev, pos, &ulpq->lobby);
+	else
+		__skb_queue_tail(&ulpq->lobby, event->parent);
+
+	sctp_spin_unlock_irqrestore(&ulpq->lobby.lock, flags);
+}
+
+static inline sctp_ulpevent_t *sctp_ulpqueue_order(sctp_ulpqueue_t *ulpq,
+						   sctp_ulpevent_t *event)
+{
+	__u16 sid, ssn;
+
+	/* FIXME: We should be using some new chunk structure here
+	 * instead of carrying chunk fields in the event structure.
+	 * This is temporary as it is too painful to change everything
+	 * at once.
+	 */
+
+	/* Check if this message needs ordering.  */
+	if (SCTP_DATA_UNORDERED & event->chunk_flags)
+		return event;	       
+
+	/* Note: The stream ID must be verified before this routine.  */
+	sid = event->sndrcvinfo.sinfo_stream;
+	ssn = event->sndrcvinfo.sinfo_ssn;
+
+	/* Is this the expected SSN for this stream ID?  */
+	if (ssn != ulpq->ssn[sid]) {
+		/* We've received something out of order, so find where it
+		 * needs to be placed.  We order by stream and then by SSN.
+		 */
+		sctp_ulpqueue_store_ordered(ulpq, event);
+		return NULL;
+	}
+
+	/* Mark that the next chunk has been found.  */
+	ulpq->ssn[sid]++;
+
+	/* Go find any other chunks that were waiting for
+	 * ordering.
+	 */
+	sctp_ulpqueue_retrieve_ordered(ulpq, event);
+
+	return event;
+}