1/*
2 * Copyright (c) 2007-2012 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29/*	$NetBSD: altq_blue.c,v 1.21 2006/11/16 01:32:37 christos Exp $	*/
30/*	$KAME: altq_blue.c,v 1.15 2005/04/13 03:44:24 suz Exp $	*/
31
32/*
33 * Copyright (C) 1997-2002
34 *	Sony Computer Science Laboratories Inc.  All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 *    notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 *    notice, this list of conditions and the following disclaimer in the
43 *    documentation and/or other materials provided with the distribution.
44 *
45 * THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND
46 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48 * ARE DISCLAIMED.  IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE
49 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55 * SUCH DAMAGE.
56 *
57 */
58/*
59 * Copyright (c) 1990-1994 Regents of the University of California.
60 * All rights reserved.
61 *
62 * Redistribution and use in source and binary forms, with or without
63 * modification, are permitted provided that the following conditions
64 * are met:
65 * 1. Redistributions of source code must retain the above copyright
66 *    notice, this list of conditions and the following disclaimer.
67 * 2. Redistributions in binary form must reproduce the above copyright
68 *    notice, this list of conditions and the following disclaimer in the
69 *    documentation and/or other materials provided with the distribution.
70 * 3. All advertising materials mentioning features or use of this software
71 *    must display the following acknowledgement:
72 *	This product includes software developed by the Computer Systems
73 *	Engineering Group at Lawrence Berkeley Laboratory.
74 * 4. Neither the name of the University nor of the Laboratory may be used
75 *    to endorse or promote products derived from this software without
76 *    specific prior written permission.
77 *
78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
81 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
88 * SUCH DAMAGE.
89 */
90
91#include <sys/cdefs.h>
92
93#if CLASSQ_BLUE
94
95#include <sys/param.h>
96#include <sys/malloc.h>
97#include <sys/mbuf.h>
98#include <sys/socket.h>
99#include <sys/sockio.h>
100#include <sys/systm.h>
101#include <sys/syslog.h>
102#include <sys/proc.h>
103#include <sys/errno.h>
104#include <sys/kernel.h>
105#include <sys/kauth.h>
106
107#include <kern/zalloc.h>
108
109#include <net/if.h>
110#include <net/if_var.h>
111#include <net/if_types.h>
112
113#include <netinet/in.h>
114#include <netinet/in_systm.h>
115#include <netinet/ip.h>
116#if INET6
117#include <netinet/ip6.h>
118#endif
119
120#include <net/classq/classq_blue.h>
121#include <net/net_osdep.h>
122#include <dev/random/randomdev.h>
123
124/*
125 * Blue is proposed and implemented by Wu-chang Feng <wuchang@eecs.umich.edu>.
126 * more information on Blue is available from
127 * http://www.eecs.umich.edu/~wuchang/blue/
128 */
129
130#define	BLUE_LIMIT	200		/* default max queue lenght */
131
132#define	BLUE_ZONE_MAX	32		/* maximum elements in zone */
133#define	BLUE_ZONE_NAME	"classq_blue"	/* zone name */
134
135static unsigned int blue_size;		/* size of zone element */
136static struct zone *blue_zone;		/* zone for blue */
137
138/* internal function prototypes */
139static struct mbuf *blue_getq_flow(struct blue *, class_queue_t *,
140    u_int32_t, boolean_t);
141static int blue_drop_early(struct blue *);
142
143void
144blue_init(void)
145{
146	_CASSERT(BLUEF_ECN4 == CLASSQF_ECN4);
147	_CASSERT(BLUEF_ECN6 == CLASSQF_ECN6);
148
149	blue_size = sizeof (struct blue);
150	blue_zone = zinit(blue_size, BLUE_ZONE_MAX * blue_size,
151	    0, BLUE_ZONE_NAME);
152	if (blue_zone == NULL) {
153		panic("%s: failed allocating %s", __func__, BLUE_ZONE_NAME);
154		/* NOTREACHED */
155	}
156	zone_change(blue_zone, Z_EXPAND, TRUE);
157	zone_change(blue_zone, Z_CALLERACCT, TRUE);
158}
159
160/*
161 * blue support routines
162 */
163struct blue *
164blue_alloc(struct ifnet *ifp, u_int32_t max_pmark, u_int32_t hold_time,
165    u_int32_t flags)
166{
167	struct blue *bp;
168
169	VERIFY(ifp != NULL);
170
171	bp = zalloc(blue_zone);
172	if (bp == NULL)
173		return (NULL);
174
175	bzero(bp, blue_size);
176	bp->blue_idle = 1;
177	bp->blue_ifp = ifp;
178	bp->blue_flags = (flags & BLUEF_USERFLAGS);
179#if !PF_ECN
180	if (bp->blue_flags & BLUEF_ECN) {
181		bp->blue_flags &= ~BLUEF_ECN;
182		log(LOG_ERR, "%s: BLUE ECN not available; ignoring "
183		    "BLUEF_ECN flag!\n", if_name(ifp));
184	}
185#endif /* !PF_ECN */
186
187
188	if (max_pmark == 0)
189		bp->blue_max_pmark = 1000;
190	else
191		bp->blue_max_pmark = max_pmark;
192
193	if (hold_time == 0)
194		bp->blue_hold_time = 50000;
195	else
196		bp->blue_hold_time = hold_time;
197
198	microuptime(&bp->blue_last);
199
200	return (bp);
201}
202
203void
204blue_destroy(struct blue *bp)
205{
206	zfree(blue_zone, bp);
207}
208
209void
210blue_getstats(struct blue *bp, struct blue_stats *sp)
211{
212	sp->q_pmark		= bp->blue_pmark;
213	sp->drop_forced		= bp->blue_stats.drop_forced;
214	sp->drop_unforced	= bp->blue_stats.drop_unforced;
215	sp->marked_packets	= bp->blue_stats.marked_packets;
216}
217
218#define	DTYPE_NODROP	0	/* no drop */
219#define	DTYPE_FORCED	1	/* a "forced" drop */
220#define	DTYPE_EARLY	2	/* an "unforced" (early) drop */
221
222int
223blue_addq(struct blue *bp, class_queue_t *q, struct mbuf *m,
224    struct pf_mtag *tag)
225{
226#if !PF_ECN
227#pragma unused(tag)
228#endif /* !PF_ECN */
229	int droptype;
230
231	/*
232	 * if we were idle, this is an enqueue onto an empty queue
233	 * and we should decrement marking probability
234	 */
235	if (bp->blue_idle) {
236		struct timeval now;
237		u_int32_t t;
238
239		bp->blue_idle = 0;
240		microuptime(&now);
241		t = (now.tv_sec - bp->blue_last.tv_sec);
242		if (t > 1) {
243			bp->blue_pmark = 1;
244			microuptime(&bp->blue_last);
245		} else {
246			t = t * 1000000 + (now.tv_usec - bp->blue_last.tv_usec);
247			if (t > bp->blue_hold_time) {
248				bp->blue_pmark--;
249				if (bp->blue_pmark < 0)
250					bp->blue_pmark = 0;
251				microuptime(&bp->blue_last);
252			}
253		}
254	}
255
256	/* see if we drop early */
257	droptype = DTYPE_NODROP;
258	if (blue_drop_early(bp) && qlen(q) > 1) {
259		/* mark or drop by blue */
260#if PF_ECN
261		if ((bp->blue_flags & BLUEF_ECN) &&
262		    (tag->pftag_proto == IPPROTO_TCP) && /* only for TCP */
263		    mark_ecn(m, tag, bp->blue_flags)) {
264			/* successfully marked.  do not drop. */
265			bp->blue_stats.marked_packets++;
266		} else
267#endif /* PF_ECN */
268		{
269			/* unforced drop by blue */
270			droptype = DTYPE_EARLY;
271		}
272	}
273
274	/* if the queue length hits the hard limit, it's a forced drop */
275	if (droptype == DTYPE_NODROP && qlen(q) >= qlimit(q))
276		droptype = DTYPE_FORCED;
277
278	/* if successful or forced drop, enqueue this packet. */
279	if (droptype != DTYPE_EARLY)
280		_addq(q, m);
281
282	if (droptype != DTYPE_NODROP) {
283		if (droptype == DTYPE_EARLY) {
284			/* drop the incoming packet */
285			bp->blue_stats.drop_unforced++;
286		} else {
287			struct timeval now;
288			u_int32_t t;
289			/* forced drop, select a victim packet in the queue. */
290			m = _getq_random(q);
291			microuptime(&now);
292			t = (now.tv_sec - bp->blue_last.tv_sec);
293			t = t * 1000000 + (now.tv_usec - bp->blue_last.tv_usec);
294			if (t > bp->blue_hold_time) {
295				bp->blue_pmark += bp->blue_max_pmark >> 3;
296				if (bp->blue_pmark > bp->blue_max_pmark)
297					bp->blue_pmark = bp->blue_max_pmark;
298				microuptime(&bp->blue_last);
299			}
300			bp->blue_stats.drop_forced++;
301		}
302		IFCQ_CONVERT_LOCK(&bp->blue_ifp->if_snd);
303		m_freem(m);
304		return (CLASSQEQ_DROPPED);
305	}
306	/* successfully queued */
307	return (CLASSQEQ_SUCCESS);
308}
309
310static struct mbuf *
311blue_getq_flow(struct blue *bp, class_queue_t *q, u_int32_t flow,
312    boolean_t purge)
313{
314#pragma unused(purge)
315	struct mbuf *m;
316
317	/* flow of 0 means head of queue */
318	if ((m = ((flow == 0) ? _getq(q) : _getq_flow(q, flow))) == NULL) {
319		if (bp->blue_idle == 0) {
320			bp->blue_idle = 1;
321			microuptime(&bp->blue_last);
322		}
323		return (NULL);
324	}
325
326	bp->blue_idle = 0;
327	return (m);
328}
329
330struct mbuf *
331blue_getq(struct blue *bp, class_queue_t *q)
332{
333	return (blue_getq_flow(bp, q, 0, FALSE));
334}
335
336void
337blue_purgeq(struct blue *bp, class_queue_t *q, u_int32_t flow,
338    u_int32_t *packets, u_int32_t *bytes)
339{
340	u_int32_t cnt = 0, len = 0;
341	struct mbuf *m;
342
343	IFCQ_CONVERT_LOCK(&bp->blue_ifp->if_snd);
344
345	while ((m = blue_getq_flow(bp, q, flow, TRUE)) != NULL) {
346		cnt++;
347		len += m_pktlen(m);
348		m_freem(m);
349	}
350
351	if (packets != NULL)
352		*packets = cnt;
353	if (bytes != NULL)
354		*bytes = len;
355}
356
357/*
358 * early-drop probability is kept in blue_pmark
359 */
360static int
361blue_drop_early(struct blue *bp)
362{
363	if ((RandomULong() % (unsigned)bp->blue_max_pmark) <
364	    (unsigned)bp->blue_pmark) {
365		/* drop or mark */
366		return (1);
367	}
368	/* no drop/mark */
369	return (0);
370}
371
372void
373blue_updateq(struct blue *bp, cqev_t ev)
374{
375#pragma unused(bp, ev)
376	/* nothing for now */
377}
378
379int
380blue_suspendq(struct blue *bp, class_queue_t *q, boolean_t on)
381{
382#pragma unused(bp, q, on)
383	return (ENOTSUP);
384}
385#endif /* CLASSQ_BLUE */
386