xref: /titanic_44/usr/src/uts/common/inet/tcp/tcp_tunables.c (revision a05fd0c9b9aa46cf66ddea7617e56facdf1f4aaf)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, Joyent Inc. All rights reserved.
24  * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
25  * Copyright (c) 2013 by Delphix. All rights reserved.
26  */
27 /* Copyright (c) 1990 Mentat Inc. */
28 
29 #include <inet/ip.h>
30 #include <inet/tcp_impl.h>
31 #include <sys/multidata.h>
32 #include <sys/sunddi.h>
33 
34 /* Max size IP datagram is 64k - 1 */
35 #define	TCP_MSS_MAX_IPV4 (IP_MAXPACKET - (sizeof (ipha_t) + sizeof (tcpha_t)))
36 #define	TCP_MSS_MAX_IPV6 (IP_MAXPACKET - (sizeof (ip6_t) + sizeof (tcpha_t)))
37 
38 /* Max of the above */
39 #define	TCP_MSS_MAX		TCP_MSS_MAX_IPV4
40 
41 /*
42  * Set the RFC 1948 pass phrase
43  */
44 /* ARGSUSED */
45 static int
46 tcp_set_1948phrase(netstack_t *stack,  cred_t *cr, mod_prop_info_t *pinfo,
47     const char *ifname, const void* pr_val, uint_t flags)
48 {
49 	if (flags & MOD_PROP_DEFAULT)
50 		return (ENOTSUP);
51 
52 	/*
53 	 * Basically, value contains a new pass phrase.  Pass it along!
54 	 */
55 	tcp_iss_key_init((uint8_t *)pr_val, strlen(pr_val),
56 	    stack->netstack_tcp);
57 	return (0);
58 }
59 
60 /*
61  * returns the current list of listener limit configuration.
62  */
63 /* ARGSUSED */
64 static int
65 tcp_listener_conf_get(netstack_t *stack, mod_prop_info_t *pinfo,
66     const char *ifname, void *val, uint_t psize, uint_t flags)
67 {
68 	tcp_stack_t	*tcps = stack->netstack_tcp;
69 	tcp_listener_t	*tl;
70 	char		*pval = val;
71 	size_t		nbytes = 0, tbytes = 0;
72 	uint_t		size;
73 	int		err = 0;
74 
75 	bzero(pval, psize);
76 	size = psize;
77 
78 	if (flags & (MOD_PROP_DEFAULT|MOD_PROP_PERM|MOD_PROP_POSSIBLE))
79 		return (0);
80 
81 	mutex_enter(&tcps->tcps_listener_conf_lock);
82 	for (tl = list_head(&tcps->tcps_listener_conf); tl != NULL;
83 	    tl = list_next(&tcps->tcps_listener_conf, tl)) {
84 		if (psize == size)
85 			nbytes = snprintf(pval, size, "%d:%d",  tl->tl_port,
86 			    tl->tl_ratio);
87 		else
88 			nbytes = snprintf(pval, size, ",%d:%d",  tl->tl_port,
89 			    tl->tl_ratio);
90 		size -= nbytes;
91 		pval += nbytes;
92 		tbytes += nbytes;
93 		if (tbytes >= psize) {
94 			/* Buffer overflow, stop copying information */
95 			err = ENOBUFS;
96 			break;
97 		}
98 	}
99 
100 	mutex_exit(&tcps->tcps_listener_conf_lock);
101 	return (err);
102 }
103 
104 /*
105  * add a new listener limit configuration.
106  */
107 /* ARGSUSED */
108 static int
109 tcp_listener_conf_add(netstack_t *stack, cred_t *cr, mod_prop_info_t *pinfo,
110     const char *ifname, const void* pval, uint_t flags)
111 {
112 	tcp_listener_t	*new_tl;
113 	tcp_listener_t	*tl;
114 	long		lport;
115 	long		ratio;
116 	char		*colon;
117 	tcp_stack_t	*tcps = stack->netstack_tcp;
118 
119 	if (flags & MOD_PROP_DEFAULT)
120 		return (ENOTSUP);
121 
122 	if (ddi_strtol(pval, &colon, 10, &lport) != 0 || lport <= 0 ||
123 	    lport > USHRT_MAX || *colon != ':') {
124 		return (EINVAL);
125 	}
126 	if (ddi_strtol(colon + 1, NULL, 10, &ratio) != 0 || ratio <= 0)
127 		return (EINVAL);
128 
129 	mutex_enter(&tcps->tcps_listener_conf_lock);
130 	for (tl = list_head(&tcps->tcps_listener_conf); tl != NULL;
131 	    tl = list_next(&tcps->tcps_listener_conf, tl)) {
132 		/* There is an existing entry, so update its ratio value. */
133 		if (tl->tl_port == lport) {
134 			tl->tl_ratio = ratio;
135 			mutex_exit(&tcps->tcps_listener_conf_lock);
136 			return (0);
137 		}
138 	}
139 
140 	if ((new_tl = kmem_alloc(sizeof (tcp_listener_t), KM_NOSLEEP)) ==
141 	    NULL) {
142 		mutex_exit(&tcps->tcps_listener_conf_lock);
143 		return (ENOMEM);
144 	}
145 
146 	new_tl->tl_port = lport;
147 	new_tl->tl_ratio = ratio;
148 	list_insert_tail(&tcps->tcps_listener_conf, new_tl);
149 	mutex_exit(&tcps->tcps_listener_conf_lock);
150 	return (0);
151 }
152 
153 /*
154  * remove a listener limit configuration.
155  */
156 /* ARGSUSED */
157 static int
158 tcp_listener_conf_del(netstack_t *stack, cred_t *cr, mod_prop_info_t *pinfo,
159     const char *ifname, const void* pval, uint_t flags)
160 {
161 	tcp_listener_t	*tl;
162 	long		lport;
163 	tcp_stack_t	*tcps = stack->netstack_tcp;
164 
165 	if (flags & MOD_PROP_DEFAULT)
166 		return (ENOTSUP);
167 
168 	if (ddi_strtol(pval, NULL, 10, &lport) != 0 || lport <= 0 ||
169 	    lport > USHRT_MAX) {
170 		return (EINVAL);
171 	}
172 	mutex_enter(&tcps->tcps_listener_conf_lock);
173 	for (tl = list_head(&tcps->tcps_listener_conf); tl != NULL;
174 	    tl = list_next(&tcps->tcps_listener_conf, tl)) {
175 		if (tl->tl_port == lport) {
176 			list_remove(&tcps->tcps_listener_conf, tl);
177 			mutex_exit(&tcps->tcps_listener_conf_lock);
178 			kmem_free(tl, sizeof (tcp_listener_t));
179 			return (0);
180 		}
181 	}
182 	mutex_exit(&tcps->tcps_listener_conf_lock);
183 	return (ESRCH);
184 }
185 
186 static int
187 tcp_set_buf_prop(netstack_t *stack, cred_t *cr, mod_prop_info_t *pinfo,
188     const char *ifname, const void *pval, uint_t flags)
189 {
190 	return (mod_set_buf_prop(stack->netstack_tcp->tcps_propinfo_tbl, stack,
191 	    cr, pinfo, ifname, pval, flags));
192 }
193 
194 static int
195 tcp_get_buf_prop(netstack_t *stack, mod_prop_info_t *pinfo, const char *ifname,
196     void *val, uint_t psize, uint_t flags)
197 {
198 	return (mod_get_buf_prop(stack->netstack_tcp->tcps_propinfo_tbl, stack,
199 	    pinfo, ifname, val, psize, flags));
200 }
201 
202 /*
203  * Special checkers for smallest/largest anonymous port so they don't
204  * ever happen to be (largest < smallest).
205  */
206 /* ARGSUSED */
207 static int
208 tcp_smallest_anon_set(netstack_t *stack, cred_t *cr, mod_prop_info_t *pinfo,
209     const char *ifname, const void *pval, uint_t flags)
210 {
211 	unsigned long new_value;
212 	tcp_stack_t *tcps = stack->netstack_tcp;
213 	int err;
214 
215 	if ((err = mod_uint32_value(pval, pinfo, flags, &new_value)) != 0)
216 		return (err);
217 	/* mod_uint32_value() + pinfo guarantees we're in TCP port range. */
218 	if ((uint32_t)new_value > tcps->tcps_largest_anon_port)
219 		return (ERANGE);
220 	pinfo->prop_cur_uval = (uint32_t)new_value;
221 	return (0);
222 }
223 
224 /* ARGSUSED */
225 static int
226 tcp_largest_anon_set(netstack_t *stack, cred_t *cr, mod_prop_info_t *pinfo,
227     const char *ifname, const void *pval, uint_t flags)
228 {
229 	unsigned long new_value;
230 	tcp_stack_t *tcps = stack->netstack_tcp;
231 	int err;
232 
233 	if ((err = mod_uint32_value(pval, pinfo, flags, &new_value)) != 0)
234 		return (err);
235 	/* mod_uint32_value() + pinfo guarantees we're in TCP port range. */
236 	if ((uint32_t)new_value < tcps->tcps_smallest_anon_port)
237 		return (ERANGE);
238 	pinfo->prop_cur_uval = (uint32_t)new_value;
239 	return (0);
240 }
241 
242 /*
243  * All of these are alterable, within the min/max values given, at run time.
244  *
245  * Note: All those tunables which do not start with "_" are Committed and
246  * therefore are public. See PSARC 2010/080.
247  */
248 mod_prop_info_t tcp_propinfo_tbl[] = {
249 	/* tunable - 0 */
250 	{ "_time_wait_interval", MOD_PROTO_TCP,
251 	    mod_set_uint32, mod_get_uint32,
252 	    {1*SECONDS, 10*MINUTES, 1*MINUTES}, {1*MINUTES} },
253 
254 	{ "_conn_req_max_q", MOD_PROTO_TCP,
255 	    mod_set_uint32, mod_get_uint32,
256 	    {1, UINT32_MAX, 128}, {128} },
257 
258 	{ "_conn_req_max_q0", MOD_PROTO_TCP,
259 	    mod_set_uint32, mod_get_uint32,
260 	    {0, UINT32_MAX, 1024}, {1024} },
261 
262 	{ "_conn_req_min", MOD_PROTO_TCP,
263 	    mod_set_uint32, mod_get_uint32,
264 	    {1, 1024, 1}, {1} },
265 
266 	{ "_conn_grace_period", MOD_PROTO_TCP,
267 	    mod_set_uint32, mod_get_uint32,
268 	    {0*MS, 20*SECONDS, 0*MS}, {0*MS} },
269 
270 	{ "_cwnd_max", MOD_PROTO_TCP,
271 	    mod_set_uint32, mod_get_uint32,
272 	    {128, ULP_MAX_BUF, 1024*1024}, {1024*1024} },
273 
274 	{ "_debug", MOD_PROTO_TCP,
275 	    mod_set_uint32, mod_get_uint32,
276 	    {0, 10, 0}, {0} },
277 
278 	{ "smallest_nonpriv_port", MOD_PROTO_TCP,
279 	    mod_set_uint32, mod_get_uint32,
280 	    {1024, (32*1024), 1024}, {1024} },
281 
282 	{ "_ip_abort_cinterval", MOD_PROTO_TCP,
283 	    mod_set_uint32, mod_get_uint32,
284 	    {1*SECONDS, UINT32_MAX, 3*MINUTES}, {3*MINUTES} },
285 
286 	{ "_ip_abort_linterval", MOD_PROTO_TCP,
287 	    mod_set_uint32, mod_get_uint32,
288 	    {1*SECONDS, UINT32_MAX, 3*MINUTES}, {3*MINUTES} },
289 
290 	/* tunable - 10 */
291 	{ "_ip_abort_interval", MOD_PROTO_TCP,
292 	    mod_set_uint32, mod_get_uint32,
293 	    {500*MS, UINT32_MAX, 5*MINUTES}, {5*MINUTES} },
294 
295 	{ "_ip_notify_cinterval", MOD_PROTO_TCP,
296 	    mod_set_uint32, mod_get_uint32,
297 	    {1*SECONDS, UINT32_MAX, 10*SECONDS},
298 	    {10*SECONDS} },
299 
300 	{ "_ip_notify_interval", MOD_PROTO_TCP,
301 	    mod_set_uint32, mod_get_uint32,
302 	    {500*MS, UINT32_MAX, 10*SECONDS}, {10*SECONDS} },
303 
304 	{ "_ipv4_ttl", MOD_PROTO_TCP,
305 	    mod_set_uint32, mod_get_uint32,
306 	    {1, 255, 64}, {64} },
307 
308 	{ "_keepalive_interval", MOD_PROTO_TCP,
309 	    mod_set_uint32, mod_get_uint32,
310 	    {10*SECONDS, 10*DAYS, 2*HOURS}, {2*HOURS} },
311 
312 	{ "_maxpsz_multiplier", MOD_PROTO_TCP,
313 	    mod_set_uint32, mod_get_uint32,
314 	    {0, 100, 10}, {10} },
315 
316 	{ "_mss_def_ipv4", MOD_PROTO_TCP,
317 	    mod_set_uint32, mod_get_uint32,
318 	    {1, TCP_MSS_MAX_IPV4, 536}, {536} },
319 
320 	{ "_mss_max_ipv4", MOD_PROTO_TCP,
321 	    mod_set_uint32, mod_get_uint32,
322 	    {1, TCP_MSS_MAX_IPV4, TCP_MSS_MAX_IPV4},
323 	    {TCP_MSS_MAX_IPV4} },
324 
325 	{ "_mss_min", MOD_PROTO_TCP,
326 	    mod_set_uint32, mod_get_uint32,
327 	    {1, TCP_MSS_MAX, 108}, {108} },
328 
329 	{ "_naglim_def", MOD_PROTO_TCP,
330 	    mod_set_uint32, mod_get_uint32,
331 	    {1, (64*1024)-1, (4*1024)-1}, {(4*1024)-1} },
332 
333 	/* tunable - 20 */
334 	{ "_rexmit_interval_initial", MOD_PROTO_TCP,
335 	    mod_set_uint32, mod_get_uint32,
336 	    {1*MS, 20*SECONDS, 1*SECONDS}, {1*SECONDS} },
337 
338 	{ "_rexmit_interval_max", MOD_PROTO_TCP,
339 	    mod_set_uint32, mod_get_uint32,
340 	    {1*MS, 2*HOURS, 60*SECONDS}, {60*SECONDS} },
341 
342 	{ "_rexmit_interval_min", MOD_PROTO_TCP,
343 	    mod_set_uint32, mod_get_uint32,
344 	    {1*MS, 2*HOURS, 400*MS}, {400*MS} },
345 
346 	{ "_deferred_ack_interval", MOD_PROTO_TCP,
347 	    mod_set_uint32, mod_get_uint32,
348 	    {1*MS, 1*MINUTES, 100*MS}, {100*MS} },
349 
350 	{ "_snd_lowat_fraction", MOD_PROTO_TCP,
351 	    mod_set_uint32, mod_get_uint32,
352 	    {0, 16, 10}, {10} },
353 
354 	{ "_dupack_fast_retransmit", MOD_PROTO_TCP,
355 	    mod_set_uint32, mod_get_uint32,
356 	    {1, 10000, 3}, {3} },
357 
358 	{ "_ignore_path_mtu", MOD_PROTO_TCP,
359 	    mod_set_boolean, mod_get_boolean,
360 	    {B_FALSE}, {B_FALSE} },
361 
362 	{ "smallest_anon_port", MOD_PROTO_TCP,
363 	    tcp_smallest_anon_set, mod_get_uint32,
364 	    {1024, ULP_MAX_PORT, 32*1024}, {32*1024} },
365 
366 	{ "largest_anon_port", MOD_PROTO_TCP,
367 	    tcp_largest_anon_set, mod_get_uint32,
368 	    {1024, ULP_MAX_PORT, ULP_MAX_PORT},
369 	    {ULP_MAX_PORT} },
370 
371 	{ "send_buf", MOD_PROTO_TCP,
372 	    tcp_set_buf_prop, tcp_get_buf_prop,
373 	    {TCP_XMIT_LOWATER, ULP_MAX_BUF, TCP_XMIT_HIWATER},
374 	    {TCP_XMIT_HIWATER} },
375 
376 	/* tunable - 30 */
377 	{ "_xmit_lowat", MOD_PROTO_TCP,
378 	    mod_set_uint32, mod_get_uint32,
379 	    {TCP_XMIT_LOWATER, ULP_MAX_BUF, TCP_XMIT_LOWATER},
380 	    {TCP_XMIT_LOWATER} },
381 
382 	{ "recv_buf", MOD_PROTO_TCP,
383 	    tcp_set_buf_prop, tcp_get_buf_prop,
384 	    {TCP_RECV_LOWATER, ULP_MAX_BUF, TCP_RECV_HIWATER},
385 	    {TCP_RECV_HIWATER} },
386 
387 	{ "_recv_hiwat_minmss", MOD_PROTO_TCP,
388 	    mod_set_uint32, mod_get_uint32,
389 	    {1, 65536, 4}, {4} },
390 
391 	{ "_fin_wait_2_flush_interval", MOD_PROTO_TCP,
392 	    mod_set_uint32, mod_get_uint32,
393 	    {1*SECONDS, 2*HOURS, 60*SECONDS},
394 	    {60*SECONDS} },
395 
396 	{ "max_buf", MOD_PROTO_TCP,
397 	    mod_set_uint32, mod_get_uint32,
398 	    {8192, ULP_MAX_BUF, 1024*1024}, {1024*1024} },
399 
400 	{ "_strong_iss", MOD_PROTO_TCP,
401 	    mod_set_uint32, mod_get_uint32,
402 	    {0, 2, 2}, {2} },
403 
404 	{ "_rtt_updates", MOD_PROTO_TCP,
405 	    mod_set_uint32, mod_get_uint32,
406 	    {0, 65536, 20}, {20} },
407 
408 	{ "_wscale_always", MOD_PROTO_TCP,
409 	    mod_set_boolean, mod_get_boolean,
410 	    {B_TRUE}, {B_TRUE} },
411 
412 	{ "_tstamp_always", MOD_PROTO_TCP,
413 	    mod_set_boolean, mod_get_boolean,
414 	    {B_FALSE}, {B_FALSE} },
415 
416 	{ "_tstamp_if_wscale", MOD_PROTO_TCP,
417 	    mod_set_boolean, mod_get_boolean,
418 	    {B_TRUE}, {B_TRUE} },
419 
420 	/* tunable - 40 */
421 	{ "_rexmit_interval_extra", MOD_PROTO_TCP,
422 	    mod_set_uint32, mod_get_uint32,
423 	    {0*MS, 2*HOURS, 0*MS}, {0*MS} },
424 
425 	{ "_deferred_acks_max", MOD_PROTO_TCP,
426 	    mod_set_uint32, mod_get_uint32,
427 	    {0, 16, 2}, {2} },
428 
429 	{ "_slow_start_after_idle", MOD_PROTO_TCP,
430 	    mod_set_uint32, mod_get_uint32,
431 	    {0, 16384, 0}, {0} },
432 
433 	{ "_slow_start_initial", MOD_PROTO_TCP,
434 	    mod_set_uint32, mod_get_uint32,
435 	    {0, 16, 0}, {0} },
436 
437 	{ "sack", MOD_PROTO_TCP,
438 	    mod_set_uint32, mod_get_uint32,
439 	    {0, 2, 2}, {2} },
440 
441 	{ "_ipv6_hoplimit", MOD_PROTO_TCP,
442 	    mod_set_uint32, mod_get_uint32,
443 	    {0, IPV6_MAX_HOPS, IPV6_DEFAULT_HOPS},
444 	    {IPV6_DEFAULT_HOPS} },
445 
446 	{ "_mss_def_ipv6", MOD_PROTO_TCP,
447 	    mod_set_uint32, mod_get_uint32,
448 	    {1, TCP_MSS_MAX_IPV6, 1220}, {1220} },
449 
450 	{ "_mss_max_ipv6", MOD_PROTO_TCP,
451 	    mod_set_uint32, mod_get_uint32,
452 	    {1, TCP_MSS_MAX_IPV6, TCP_MSS_MAX_IPV6},
453 	    {TCP_MSS_MAX_IPV6} },
454 
455 	{ "_rev_src_routes", MOD_PROTO_TCP,
456 	    mod_set_boolean, mod_get_boolean,
457 	    {B_FALSE}, {B_FALSE} },
458 
459 	{ "_local_dack_interval", MOD_PROTO_TCP,
460 	    mod_set_uint32, mod_get_uint32,
461 	    {10*MS, 500*MS, 50*MS}, {50*MS} },
462 
463 	/* tunable - 50 */
464 	{ "_local_dacks_max", MOD_PROTO_TCP,
465 	    mod_set_uint32, mod_get_uint32,
466 	    {0, 16, 8}, {8} },
467 
468 	{ "ecn", MOD_PROTO_TCP,
469 	    mod_set_uint32, mod_get_uint32,
470 	    {0, 2, 1}, {1} },
471 
472 	{ "_rst_sent_rate_enabled", MOD_PROTO_TCP,
473 	    mod_set_boolean, mod_get_boolean,
474 	    {B_TRUE}, {B_TRUE} },
475 
476 	{ "_rst_sent_rate", MOD_PROTO_TCP,
477 	    mod_set_uint32, mod_get_uint32,
478 	    {0, UINT32_MAX, 40}, {40} },
479 
480 	{ "_push_timer_interval", MOD_PROTO_TCP,
481 	    mod_set_uint32, mod_get_uint32,
482 	    {0, 100*MS, 50*MS}, {50*MS} },
483 
484 	{ "_use_smss_as_mss_opt", MOD_PROTO_TCP,
485 	    mod_set_boolean, mod_get_boolean,
486 	    {B_FALSE}, {B_FALSE} },
487 
488 	{ "_keepalive_abort_interval", MOD_PROTO_TCP,
489 	    mod_set_uint32, mod_get_uint32,
490 	    {0, UINT32_MAX, 8*MINUTES}, {8*MINUTES} },
491 
492 	/*
493 	 * tcp_wroff_xtra is the extra space in front of TCP/IP header for link
494 	 * layer header.  It has to be a multiple of 8.
495 	 */
496 	{ "_wroff_xtra", MOD_PROTO_TCP,
497 	    mod_set_aligned, mod_get_uint32,
498 	    {0, 256, 32}, {32} },
499 
500 	{ "_dev_flow_ctl", MOD_PROTO_TCP,
501 	    mod_set_boolean, mod_get_boolean,
502 	    {B_FALSE}, {B_FALSE} },
503 
504 	{ "_reass_timeout", MOD_PROTO_TCP,
505 	    mod_set_uint32, mod_get_uint32,
506 	    {0, UINT32_MAX, 100*SECONDS}, {100*SECONDS} },
507 
508 	/* tunable - 60 */
509 	{ "extra_priv_ports", MOD_PROTO_TCP,
510 	    mod_set_extra_privports, mod_get_extra_privports,
511 	    {1, ULP_MAX_PORT, 0}, {0} },
512 
513 	{ "_1948_phrase", MOD_PROTO_TCP,
514 	    tcp_set_1948phrase, NULL, {0}, {0} },
515 
516 	{ "_listener_limit_conf", MOD_PROTO_TCP,
517 	    NULL, tcp_listener_conf_get, {0}, {0} },
518 
519 	{ "_listener_limit_conf_add", MOD_PROTO_TCP,
520 	    tcp_listener_conf_add, NULL, {0}, {0} },
521 
522 	{ "_listener_limit_conf_del", MOD_PROTO_TCP,
523 	    tcp_listener_conf_del, NULL, {0}, {0} },
524 
525 	{ "_iss_incr", MOD_PROTO_TCP,
526 	    mod_set_uint32, mod_get_uint32,
527 	    {1, ISS_INCR, ISS_INCR},
528 	    {ISS_INCR} },
529 
530 	{ "?", MOD_PROTO_TCP, NULL, mod_get_allprop, {0}, {0} },
531 
532 	{ NULL, 0, NULL, NULL, {0}, {0} }
533 };
534 
535 int tcp_propinfo_count = A_CNT(tcp_propinfo_tbl);
536