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 /*
23 * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
25 * Copyright (c) 2013, 2017 by Delphix. All rights reserved.
26 * Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
27 * Copyright 2020 Joyent, Inc.
28 */
29 /* Copyright (c) 1990 Mentat Inc. */
30
31 #include <sys/types.h>
32 #include <sys/stream.h>
33 #include <sys/strsun.h>
34 #include <sys/strsubr.h>
35 #include <sys/stropts.h>
36 #include <sys/strlog.h>
37 #define _SUN_TPI_VERSION 2
38 #include <sys/tihdr.h>
39 #include <sys/timod.h>
40 #include <sys/ddi.h>
41 #include <sys/sunddi.h>
42 #include <sys/suntpi.h>
43 #include <sys/xti_inet.h>
44 #include <sys/cmn_err.h>
45 #include <sys/debug.h>
46 #include <sys/sdt.h>
47 #include <sys/vtrace.h>
48 #include <sys/kmem.h>
49 #include <sys/ethernet.h>
50 #include <sys/cpuvar.h>
51 #include <sys/dlpi.h>
52 #include <sys/pattr.h>
53 #include <sys/policy.h>
54 #include <sys/priv.h>
55 #include <sys/zone.h>
56 #include <sys/sunldi.h>
57
58 #include <sys/errno.h>
59 #include <sys/signal.h>
60 #include <sys/socket.h>
61 #include <sys/socketvar.h>
62 #include <sys/sockio.h>
63 #include <sys/isa_defs.h>
64 #include <sys/md5.h>
65 #include <sys/random.h>
66 #include <sys/uio.h>
67 #include <sys/systm.h>
68 #include <netinet/in.h>
69 #include <netinet/tcp.h>
70 #include <netinet/ip6.h>
71 #include <netinet/icmp6.h>
72 #include <net/if.h>
73 #include <net/route.h>
74 #include <inet/ipsec_impl.h>
75
76 #include <inet/common.h>
77 #include <inet/cc.h>
78 #include <inet/ip.h>
79 #include <inet/ip_impl.h>
80 #include <inet/ip6.h>
81 #include <inet/ip_ndp.h>
82 #include <inet/proto_set.h>
83 #include <inet/mib2.h>
84 #include <inet/optcom.h>
85 #include <inet/snmpcom.h>
86 #include <inet/kstatcom.h>
87 #include <inet/tcp.h>
88 #include <inet/tcp_impl.h>
89 #include <inet/tcp_cluster.h>
90 #include <inet/udp_impl.h>
91 #include <net/pfkeyv2.h>
92 #include <inet/ipdrop.h>
93
94 #include <inet/ipclassifier.h>
95 #include <inet/ip_ire.h>
96 #include <inet/ip_ftable.h>
97 #include <inet/ip_if.h>
98 #include <inet/ipp_common.h>
99 #include <inet/ip_rts.h>
100 #include <inet/ip_netinfo.h>
101 #include <sys/squeue_impl.h>
102 #include <sys/squeue.h>
103 #include <sys/tsol/label.h>
104 #include <sys/tsol/tnet.h>
105 #include <rpc/pmap_prot.h>
106 #include <sys/callo.h>
107
108 /*
109 * TCP Notes: aka FireEngine Phase I (PSARC 2002/433)
110 *
111 * (Read the detailed design doc in PSARC case directory)
112 *
113 * The entire tcp state is contained in tcp_t and conn_t structure
114 * which are allocated in tandem using ipcl_conn_create() and passing
115 * IPCL_TCPCONN as a flag. We use 'conn_ref' and 'conn_lock' to protect
116 * the references on the tcp_t. The tcp_t structure is never compressed
117 * and packets always land on the correct TCP perimeter from the time
118 * eager is created till the time tcp_t dies (as such the old mentat
119 * TCP global queue is not used for detached state and no IPSEC checking
120 * is required). The global queue is still allocated to send out resets
121 * for connection which have no listeners and IP directly calls
122 * tcp_xmit_listeners_reset() which does any policy check.
123 *
124 * Protection and Synchronisation mechanism:
125 *
126 * The tcp data structure does not use any kind of lock for protecting
127 * its state but instead uses 'squeues' for mutual exclusion from various
128 * read and write side threads. To access a tcp member, the thread should
129 * always be behind squeue (via squeue_enter with flags as SQ_FILL, SQ_PROCESS,
130 * or SQ_NODRAIN). Since the squeues allow a direct function call, caller
131 * can pass any tcp function having prototype of edesc_t as argument
132 * (different from traditional STREAMs model where packets come in only
133 * designated entry points). The list of functions that can be directly
134 * called via squeue are listed before the usual function prototype.
135 *
136 * Referencing:
137 *
138 * TCP is MT-Hot and we use a reference based scheme to make sure that the
139 * tcp structure doesn't disappear when its needed. When the application
140 * creates an outgoing connection or accepts an incoming connection, we
141 * start out with 2 references on 'conn_ref'. One for TCP and one for IP.
142 * The IP reference is just a symbolic reference since ip_tcpclose()
143 * looks at tcp structure after tcp_close_output() returns which could
144 * have dropped the last TCP reference. So as long as the connection is
145 * in attached state i.e. !TCP_IS_DETACHED, we have 2 references on the
146 * conn_t. The classifier puts its own reference when the connection is
147 * inserted in listen or connected hash. Anytime a thread needs to enter
148 * the tcp connection perimeter, it retrieves the conn/tcp from q->ptr
149 * on write side or by doing a classify on read side and then puts a
150 * reference on the conn before doing squeue_enter/tryenter/fill. For
151 * read side, the classifier itself puts the reference under fanout lock
152 * to make sure that tcp can't disappear before it gets processed. The
153 * squeue will drop this reference automatically so the called function
154 * doesn't have to do a DEC_REF.
155 *
156 * Opening a new connection:
157 *
158 * The outgoing connection open is pretty simple. tcp_open() does the
159 * work in creating the conn/tcp structure and initializing it. The
160 * squeue assignment is done based on the CPU the application
161 * is running on. So for outbound connections, processing is always done
162 * on application CPU which might be different from the incoming CPU
163 * being interrupted by the NIC. An optimal way would be to figure out
164 * the NIC <-> CPU binding at listen time, and assign the outgoing
165 * connection to the squeue attached to the CPU that will be interrupted
166 * for incoming packets (we know the NIC based on the bind IP address).
167 * This might seem like a problem if more data is going out but the
168 * fact is that in most cases the transmit is ACK driven transmit where
169 * the outgoing data normally sits on TCP's xmit queue waiting to be
170 * transmitted.
171 *
172 * Accepting a connection:
173 *
174 * This is a more interesting case because of various races involved in
175 * establishing a eager in its own perimeter. Read the meta comment on
176 * top of tcp_input_listener(). But briefly, the squeue is picked by
177 * ip_fanout based on the ring or the sender (if loopback).
178 *
179 * Closing a connection:
180 *
181 * The close is fairly straight forward. tcp_close() calls tcp_close_output()
182 * via squeue to do the close and mark the tcp as detached if the connection
183 * was in state TCPS_ESTABLISHED or greater. In the later case, TCP keep its
184 * reference but tcp_close() drop IP's reference always. So if tcp was
185 * not killed, it is sitting in time_wait list with 2 reference - 1 for TCP
186 * and 1 because it is in classifier's connected hash. This is the condition
187 * we use to determine that its OK to clean up the tcp outside of squeue
188 * when time wait expires (check the ref under fanout and conn_lock and
189 * if it is 2, remove it from fanout hash and kill it).
190 *
191 * Although close just drops the necessary references and marks the
192 * tcp_detached state, tcp_close needs to know the tcp_detached has been
193 * set (under squeue) before letting the STREAM go away (because a
194 * inbound packet might attempt to go up the STREAM while the close
195 * has happened and tcp_detached is not set). So a special lock and
196 * flag is used along with a condition variable (tcp_closelock, tcp_closed,
197 * and tcp_closecv) to signal tcp_close that tcp_close_out() has marked
198 * tcp_detached.
199 *
200 * Special provisions and fast paths:
201 *
202 * We make special provisions for sockfs by marking tcp_issocket
203 * whenever we have only sockfs on top of TCP. This allows us to skip
204 * putting the tcp in acceptor hash since a sockfs listener can never
205 * become acceptor and also avoid allocating a tcp_t for acceptor STREAM
206 * since eager has already been allocated and the accept now happens
207 * on acceptor STREAM. There is a big blob of comment on top of
208 * tcp_input_listener explaining the new accept. When socket is POP'd,
209 * sockfs sends us an ioctl to mark the fact and we go back to old
210 * behaviour. Once tcp_issocket is unset, its never set for the
211 * life of that connection.
212 *
213 * IPsec notes :
214 *
215 * Since a packet is always executed on the correct TCP perimeter
216 * all IPsec processing is defered to IP including checking new
217 * connections and setting IPSEC policies for new connection. The
218 * only exception is tcp_xmit_listeners_reset() which is called
219 * directly from IP and needs to policy check to see if TH_RST
220 * can be sent out.
221 */
222
223 /*
224 * Values for squeue switch:
225 * 1: SQ_NODRAIN
226 * 2: SQ_PROCESS
227 * 3: SQ_FILL
228 */
229 int tcp_squeue_wput = 2; /* /etc/systems */
230 int tcp_squeue_flag;
231
232 /*
233 * To prevent memory hog, limit the number of entries in tcp_free_list
234 * to 1% of available memory / number of cpus
235 */
236 uint_t tcp_free_list_max_cnt = 0;
237
238 #define TIDUSZ 4096 /* transport interface data unit size */
239
240 /*
241 * Size of acceptor hash list. It has to be a power of 2 for hashing.
242 */
243 #define TCP_ACCEPTOR_FANOUT_SIZE 512
244
245 #ifdef _ILP32
246 #define TCP_ACCEPTOR_HASH(accid) \
247 (((uint_t)(accid) >> 8) & (TCP_ACCEPTOR_FANOUT_SIZE - 1))
248 #else
249 #define TCP_ACCEPTOR_HASH(accid) \
250 ((uint_t)(accid) & (TCP_ACCEPTOR_FANOUT_SIZE - 1))
251 #endif /* _ILP32 */
252
253 /*
254 * Minimum number of connections which can be created per listener. Used
255 * when the listener connection count is in effect.
256 */
257 static uint32_t tcp_min_conn_listener = 2;
258
259 uint32_t tcp_early_abort = 30;
260
261 /* TCP Timer control structure */
262 typedef struct tcpt_s {
263 pfv_t tcpt_pfv; /* The routine we are to call */
264 tcp_t *tcpt_tcp; /* The parameter we are to pass in */
265 } tcpt_t;
266
267 /*
268 * Functions called directly via squeue having a prototype of edesc_t.
269 */
270 void tcp_input_data(void *arg, mblk_t *mp, void *arg2,
271 ip_recv_attr_t *ira);
272 static void tcp_linger_interrupted(void *arg, mblk_t *mp, void *arg2,
273 ip_recv_attr_t *dummy);
274
275
276 /* Prototype for TCP functions */
277 static void tcp_random_init(void);
278 int tcp_random(void);
279 static int tcp_connect_ipv4(tcp_t *tcp, ipaddr_t *dstaddrp,
280 in_port_t dstport, uint_t srcid);
281 static int tcp_connect_ipv6(tcp_t *tcp, in6_addr_t *dstaddrp,
282 in_port_t dstport, uint32_t flowinfo,
283 uint_t srcid, uint32_t scope_id);
284 static void tcp_iss_init(tcp_t *tcp);
285 static void tcp_reinit(tcp_t *tcp);
286 static void tcp_reinit_values(tcp_t *tcp);
287
288 static int tcp_wsrv(queue_t *q);
289 static void tcp_update_lso(tcp_t *tcp, ip_xmit_attr_t *ixa);
290 static void tcp_update_zcopy(tcp_t *tcp);
291 static void tcp_notify(void *, ip_xmit_attr_t *, ixa_notify_type_t,
292 ixa_notify_arg_t);
293 static void *tcp_stack_init(netstackid_t stackid, netstack_t *ns);
294 static void tcp_stack_fini(netstackid_t stackid, void *arg);
295
296 static int tcp_squeue_switch(int);
297
298 static int tcp_open(queue_t *, dev_t *, int, int, cred_t *, boolean_t);
299 static int tcp_openv4(queue_t *, dev_t *, int, int, cred_t *);
300 static int tcp_openv6(queue_t *, dev_t *, int, int, cred_t *);
301
302 static void tcp_squeue_add(squeue_t *);
303
304 struct module_info tcp_rinfo = {
305 TCP_MOD_ID, TCP_MOD_NAME, 0, INFPSZ, TCP_RECV_HIWATER, TCP_RECV_LOWATER
306 };
307
308 static struct module_info tcp_winfo = {
309 TCP_MOD_ID, TCP_MOD_NAME, 0, INFPSZ, 127, 16
310 };
311
312 /*
313 * Entry points for TCP as a device. The normal case which supports
314 * the TCP functionality.
315 * We have separate open functions for the /dev/tcp and /dev/tcp6 devices.
316 */
317 struct qinit tcp_rinitv4 = {
318 NULL, tcp_rsrv, tcp_openv4, tcp_tpi_close, NULL, &tcp_rinfo
319 };
320
321 struct qinit tcp_rinitv6 = {
322 NULL, tcp_rsrv, tcp_openv6, tcp_tpi_close, NULL, &tcp_rinfo
323 };
324
325 struct qinit tcp_winit = {
326 tcp_wput, tcp_wsrv, NULL, NULL, NULL, &tcp_winfo
327 };
328
329 /* Initial entry point for TCP in socket mode. */
330 struct qinit tcp_sock_winit = {
331 tcp_wput_sock, tcp_wsrv, NULL, NULL, NULL, &tcp_winfo
332 };
333
334 /* TCP entry point during fallback */
335 struct qinit tcp_fallback_sock_winit = {
336 tcp_wput_fallback, NULL, NULL, NULL, NULL, &tcp_winfo
337 };
338
339 /*
340 * Entry points for TCP as a acceptor STREAM opened by sockfs when doing
341 * an accept. Avoid allocating data structures since eager has already
342 * been created.
343 */
344 struct qinit tcp_acceptor_rinit = {
345 NULL, tcp_rsrv, NULL, tcp_tpi_close_accept, NULL, &tcp_winfo
346 };
347
348 struct qinit tcp_acceptor_winit = {
349 tcp_tpi_accept, NULL, NULL, NULL, NULL, &tcp_winfo
350 };
351
352 /* For AF_INET aka /dev/tcp */
353 struct streamtab tcpinfov4 = {
354 &tcp_rinitv4, &tcp_winit
355 };
356
357 /* For AF_INET6 aka /dev/tcp6 */
358 struct streamtab tcpinfov6 = {
359 &tcp_rinitv6, &tcp_winit
360 };
361
362 /*
363 * Following assumes TPI alignment requirements stay along 32 bit
364 * boundaries
365 */
366 #define ROUNDUP32(x) \
367 (((x) + (sizeof (int32_t) - 1)) & ~(sizeof (int32_t) - 1))
368
369 /* Template for response to info request. */
370 struct T_info_ack tcp_g_t_info_ack = {
371 T_INFO_ACK, /* PRIM_type */
372 0, /* TSDU_size */
373 T_INFINITE, /* ETSDU_size */
374 T_INVALID, /* CDATA_size */
375 T_INVALID, /* DDATA_size */
376 sizeof (sin_t), /* ADDR_size */
377 0, /* OPT_size - not initialized here */
378 TIDUSZ, /* TIDU_size */
379 T_COTS_ORD, /* SERV_type */
380 TCPS_IDLE, /* CURRENT_state */
381 (XPG4_1|EXPINLINE) /* PROVIDER_flag */
382 };
383
384 struct T_info_ack tcp_g_t_info_ack_v6 = {
385 T_INFO_ACK, /* PRIM_type */
386 0, /* TSDU_size */
387 T_INFINITE, /* ETSDU_size */
388 T_INVALID, /* CDATA_size */
389 T_INVALID, /* DDATA_size */
390 sizeof (sin6_t), /* ADDR_size */
391 0, /* OPT_size - not initialized here */
392 TIDUSZ, /* TIDU_size */
393 T_COTS_ORD, /* SERV_type */
394 TCPS_IDLE, /* CURRENT_state */
395 (XPG4_1|EXPINLINE) /* PROVIDER_flag */
396 };
397
398 /*
399 * TCP tunables related declarations. Definitions are in tcp_tunables.c
400 */
401 extern mod_prop_info_t tcp_propinfo_tbl[];
402 extern int tcp_propinfo_count;
403
404 #define IS_VMLOANED_MBLK(mp) \
405 (((mp)->b_datap->db_struioflag & STRUIO_ZC) != 0)
406
407 uint32_t do_tcpzcopy = 1; /* 0: disable, 1: enable, 2: force */
408
409 /*
410 * Forces all connections to obey the value of the tcps_maxpsz_multiplier
411 * tunable settable via NDD. Otherwise, the per-connection behavior is
412 * determined dynamically during tcp_set_destination(), which is the default.
413 */
414 boolean_t tcp_static_maxpsz = B_FALSE;
415
416 /*
417 * If the receive buffer size is changed, this function is called to update
418 * the upper socket layer on the new delayed receive wake up threshold.
419 */
420 static void
421 tcp_set_recv_threshold(tcp_t *tcp, uint32_t new_rcvthresh)
422 {
423 uint32_t default_threshold = SOCKET_RECVHIWATER >> 3;
424
425 if (IPCL_IS_NONSTR(tcp->tcp_connp)) {
426 conn_t *connp = tcp->tcp_connp;
427 struct sock_proto_props sopp;
428
429 /*
430 * only increase rcvthresh upto default_threshold
431 */
432 if (new_rcvthresh > default_threshold)
433 new_rcvthresh = default_threshold;
434
435 sopp.sopp_flags = SOCKOPT_RCVTHRESH;
436 sopp.sopp_rcvthresh = new_rcvthresh;
437
438 (*connp->conn_upcalls->su_set_proto_props)
439 (connp->conn_upper_handle, &sopp);
440 }
441 }
442
443 /*
444 * Figure out the value of window scale opton. Note that the rwnd is
445 * ASSUMED to be rounded up to the nearest MSS before the calculation.
446 * We cannot find the scale value and then do a round up of tcp_rwnd
447 * because the scale value may not be correct after that.
448 *
449 * Set the compiler flag to make this function inline.
450 */
451 void
452 tcp_set_ws_value(tcp_t *tcp)
453 {
454 int i;
455 uint32_t rwnd = tcp->tcp_rwnd;
456
457 for (i = 0; rwnd > TCP_MAXWIN && i < TCP_MAX_WINSHIFT;
458 i++, rwnd >>= 1)
459 ;
460 tcp->tcp_rcv_ws = i;
461 }
462
463 /*
464 * Remove cached/latched IPsec references.
465 */
466 void
467 tcp_ipsec_cleanup(tcp_t *tcp)
468 {
469 conn_t *connp = tcp->tcp_connp;
470
471 ASSERT(connp->conn_flags & IPCL_TCPCONN);
472
473 if (connp->conn_latch != NULL) {
474 IPLATCH_REFRELE(connp->conn_latch);
475 connp->conn_latch = NULL;
476 }
477 if (connp->conn_latch_in_policy != NULL) {
478 IPPOL_REFRELE(connp->conn_latch_in_policy);
479 connp->conn_latch_in_policy = NULL;
480 }
481 if (connp->conn_latch_in_action != NULL) {
482 IPACT_REFRELE(connp->conn_latch_in_action);
483 connp->conn_latch_in_action = NULL;
484 }
485 if (connp->conn_policy != NULL) {
486 IPPH_REFRELE(connp->conn_policy, connp->conn_netstack);
487 connp->conn_policy = NULL;
488 }
489 }
490
491 /*
492 * Cleaup before placing on free list.
493 * Disassociate from the netstack/tcp_stack_t since the freelist
494 * is per squeue and not per netstack.
495 */
496 void
497 tcp_cleanup(tcp_t *tcp)
498 {
499 mblk_t *mp;
500 conn_t *connp = tcp->tcp_connp;
501 tcp_stack_t *tcps = tcp->tcp_tcps;
502 netstack_t *ns = tcps->tcps_netstack;
503 mblk_t *tcp_rsrv_mp;
504
505 tcp_bind_hash_remove(tcp);
506
507 /* Cleanup that which needs the netstack first */
508 tcp_ipsec_cleanup(tcp);
509 ixa_cleanup(connp->conn_ixa);
510
511 if (connp->conn_ht_iphc != NULL) {
512 kmem_free(connp->conn_ht_iphc, connp->conn_ht_iphc_allocated);
513 connp->conn_ht_iphc = NULL;
514 connp->conn_ht_iphc_allocated = 0;
515 connp->conn_ht_iphc_len = 0;
516 connp->conn_ht_ulp = NULL;
517 connp->conn_ht_ulp_len = 0;
518 tcp->tcp_ipha = NULL;
519 tcp->tcp_ip6h = NULL;
520 tcp->tcp_tcpha = NULL;
521 }
522
523 /* We clear any IP_OPTIONS and extension headers */
524 ip_pkt_free(&connp->conn_xmit_ipp);
525
526 tcp_free(tcp);
527
528 /*
529 * Since we will bzero the entire structure, we need to
530 * remove it and reinsert it in global hash list. We
531 * know the walkers can't get to this conn because we
532 * had set CONDEMNED flag earlier and checked reference
533 * under conn_lock so walker won't pick it and when we
534 * go the ipcl_globalhash_remove() below, no walker
535 * can get to it.
536 */
537 ipcl_globalhash_remove(connp);
538
539 /* Save some state */
540 mp = tcp->tcp_timercache;
541
542 tcp_rsrv_mp = tcp->tcp_rsrv_mp;
543
544 if (connp->conn_cred != NULL) {
545 crfree(connp->conn_cred);
546 connp->conn_cred = NULL;
547 }
548 ipcl_conn_cleanup(connp);
549 connp->conn_flags = IPCL_TCPCONN;
550
551 /*
552 * Now it is safe to decrement the reference counts.
553 * This might be the last reference on the netstack
554 * in which case it will cause the freeing of the IP Instance.
555 */
556 connp->conn_netstack = NULL;
557 connp->conn_ixa->ixa_ipst = NULL;
558 netstack_rele(ns);
559 ASSERT(tcps != NULL);
560 tcp->tcp_tcps = NULL;
561
562 bzero(tcp, sizeof (tcp_t));
563
564 /* restore the state */
565 tcp->tcp_timercache = mp;
566
567 tcp->tcp_rsrv_mp = tcp_rsrv_mp;
568
569 tcp->tcp_connp = connp;
570
571 ASSERT(connp->conn_tcp == tcp);
572 ASSERT(connp->conn_flags & IPCL_TCPCONN);
573 connp->conn_state_flags = CONN_INCIPIENT;
574 ASSERT(connp->conn_proto == IPPROTO_TCP);
575 ASSERT(connp->conn_ref == 1);
576 }
577
578 /*
579 * Adapt to the information, such as rtt and rtt_sd, provided from the
580 * DCE and IRE maintained by IP.
581 *
582 * Checks for multicast and broadcast destination address.
583 * Returns zero if ok; an errno on failure.
584 *
585 * Note that the MSS calculation here is based on the info given in
586 * the DCE and IRE. We do not do any calculation based on TCP options. They
587 * will be handled in tcp_input_data() when TCP knows which options to use.
588 *
589 * Note on how TCP gets its parameters for a connection.
590 *
591 * When a tcp_t structure is allocated, it gets all the default parameters.
592 * In tcp_set_destination(), it gets those metric parameters, like rtt, rtt_sd,
593 * spipe, rpipe, ... from the route metrics. Route metric overrides the
594 * default.
595 *
596 * An incoming SYN with a multicast or broadcast destination address is dropped
597 * in ip_fanout_v4/v6.
598 *
599 * An incoming SYN with a multicast or broadcast source address is always
600 * dropped in tcp_set_destination, since IPDF_ALLOW_MCBC is not set in
601 * conn_connect.
602 * The same logic in tcp_set_destination also serves to
603 * reject an attempt to connect to a broadcast or multicast (destination)
604 * address.
605 */
606 int
607 tcp_set_destination(tcp_t *tcp)
608 {
609 uint32_t mss_max;
610 uint32_t mss;
611 boolean_t tcp_detached = TCP_IS_DETACHED(tcp);
612 conn_t *connp = tcp->tcp_connp;
613 tcp_stack_t *tcps = tcp->tcp_tcps;
614 iulp_t uinfo;
615 int error;
616 uint32_t flags;
617
618 flags = IPDF_LSO | IPDF_ZCOPY;
619 /*
620 * Make sure we have a dce for the destination to avoid dce_ident
621 * contention for connected sockets.
622 */
623 flags |= IPDF_UNIQUE_DCE;
624
625 if (!tcps->tcps_ignore_path_mtu)
626 connp->conn_ixa->ixa_flags |= IXAF_PMTU_DISCOVERY;
627
628 /* Use conn_lock to satify ASSERT; tcp is already serialized */
629 mutex_enter(&connp->conn_lock);
630 error = conn_connect(connp, &uinfo, flags);
631 mutex_exit(&connp->conn_lock);
632 if (error != 0)
633 return (error);
634
635 error = tcp_build_hdrs(tcp);
636 if (error != 0)
637 return (error);
638
639 tcp->tcp_localnet = uinfo.iulp_localnet;
640
641 if (uinfo.iulp_rtt != 0) {
642 tcp->tcp_rtt_sa = MSEC2NSEC(uinfo.iulp_rtt);
643 tcp->tcp_rtt_sd = MSEC2NSEC(uinfo.iulp_rtt_sd);
644 tcp->tcp_rto = tcp_calculate_rto(tcp, tcps, 0);
645 }
646 if (uinfo.iulp_ssthresh != 0)
647 tcp->tcp_cwnd_ssthresh = uinfo.iulp_ssthresh;
648 else
649 tcp->tcp_cwnd_ssthresh = TCP_MAX_LARGEWIN;
650 if (uinfo.iulp_spipe > 0) {
651 connp->conn_sndbuf = MIN(uinfo.iulp_spipe,
652 tcps->tcps_max_buf);
653 if (tcps->tcps_snd_lowat_fraction != 0) {
654 connp->conn_sndlowat = connp->conn_sndbuf /
655 tcps->tcps_snd_lowat_fraction;
656 }
657 (void) tcp_maxpsz_set(tcp, B_TRUE);
658 }
659 /*
660 * Note that up till now, acceptor always inherits receive
661 * window from the listener. But if there is a metrics
662 * associated with a host, we should use that instead of
663 * inheriting it from listener. Thus we need to pass this
664 * info back to the caller.
665 */
666 if (uinfo.iulp_rpipe > 0) {
667 tcp->tcp_rwnd = MIN(uinfo.iulp_rpipe,
668 tcps->tcps_max_buf);
669 }
670
671 if (uinfo.iulp_rtomax > 0) {
672 tcp->tcp_second_timer_threshold =
673 uinfo.iulp_rtomax;
674 }
675
676 /*
677 * Use the metric option settings, iulp_tstamp_ok and
678 * iulp_wscale_ok, only for active open. What this means
679 * is that if the other side uses timestamp or window
680 * scale option, TCP will also use those options. That
681 * is for passive open. If the application sets a
682 * large window, window scale is enabled regardless of
683 * the value in iulp_wscale_ok. This is the behavior
684 * since 2.6. So we keep it.
685 * The only case left in passive open processing is the
686 * check for SACK.
687 * For ECN, it should probably be like SACK. But the
688 * current value is binary, so we treat it like the other
689 * cases. The metric only controls active open.For passive
690 * open, the ndd param, tcp_ecn_permitted, controls the
691 * behavior.
692 */
693 if (!tcp_detached) {
694 /*
695 * The if check means that the following can only
696 * be turned on by the metrics only IRE, but not off.
697 */
698 if (uinfo.iulp_tstamp_ok)
699 tcp->tcp_snd_ts_ok = B_TRUE;
700 if (uinfo.iulp_wscale_ok)
701 tcp->tcp_snd_ws_ok = B_TRUE;
702 if (uinfo.iulp_sack == 2)
703 tcp->tcp_snd_sack_ok = B_TRUE;
704 if (uinfo.iulp_ecn_ok)
705 tcp->tcp_ecn_ok = B_TRUE;
706 } else {
707 /*
708 * Passive open.
709 *
710 * As above, the if check means that SACK can only be
711 * turned on by the metric only IRE.
712 */
713 if (uinfo.iulp_sack > 0) {
714 tcp->tcp_snd_sack_ok = B_TRUE;
715 }
716 }
717
718 /*
719 * XXX Note that currently, iulp_mtu can be as small as 68
720 * because of PMTUd. So tcp_mss may go to negative if combined
721 * length of all those options exceeds 28 bytes. But because
722 * of the tcp_mss_min check below, we may not have a problem if
723 * tcp_mss_min is of a reasonable value. The default is 1 so
724 * the negative problem still exists. And the check defeats PMTUd.
725 * In fact, if PMTUd finds that the MSS should be smaller than
726 * tcp_mss_min, TCP should turn off PMUTd and use the tcp_mss_min
727 * value.
728 *
729 * We do not deal with that now. All those problems related to
730 * PMTUd will be fixed later.
731 */
732 ASSERT(uinfo.iulp_mtu != 0);
733 mss = tcp->tcp_initial_pmtu = uinfo.iulp_mtu;
734
735 /* Sanity check for MSS value. */
736 if (connp->conn_ipversion == IPV4_VERSION)
737 mss_max = tcps->tcps_mss_max_ipv4;
738 else
739 mss_max = tcps->tcps_mss_max_ipv6;
740
741 if (tcp->tcp_ipsec_overhead == 0)
742 tcp->tcp_ipsec_overhead = conn_ipsec_length(connp);
743
744 mss -= tcp->tcp_ipsec_overhead;
745
746 if (mss < tcps->tcps_mss_min)
747 mss = tcps->tcps_mss_min;
748 if (mss > mss_max)
749 mss = mss_max;
750
751 /* Note that this is the maximum MSS, excluding all options. */
752 tcp->tcp_mss = mss;
753
754 /*
755 * Update the tcp connection with LSO capability.
756 */
757 tcp_update_lso(tcp, connp->conn_ixa);
758
759 /*
760 * Initialize the ISS here now that we have the full connection ID.
761 * The RFC 1948 method of initial sequence number generation requires
762 * knowledge of the full connection ID before setting the ISS.
763 */
764 tcp_iss_init(tcp);
765
766 tcp->tcp_loopback = (uinfo.iulp_loopback | uinfo.iulp_local);
767
768 /*
769 * Make sure that conn is not marked incipient
770 * for incoming connections. A blind
771 * removal of incipient flag is cheaper than
772 * check and removal.
773 */
774 mutex_enter(&connp->conn_lock);
775 connp->conn_state_flags &= ~CONN_INCIPIENT;
776 mutex_exit(&connp->conn_lock);
777 return (0);
778 }
779
780 /*
781 * tcp_clean_death / tcp_close_detached must not be called more than once
782 * on a tcp. Thus every function that potentially calls tcp_clean_death
783 * must check for the tcp state before calling tcp_clean_death.
784 * Eg. tcp_input_data, tcp_eager_kill, tcp_clean_death_wrapper,
785 * tcp_timer_handler, all check for the tcp state.
786 */
787 /* ARGSUSED */
788 void
789 tcp_clean_death_wrapper(void *arg, mblk_t *mp, void *arg2,
790 ip_recv_attr_t *dummy)
791 {
792 tcp_t *tcp = ((conn_t *)arg)->conn_tcp;
793
794 freemsg(mp);
795 if (tcp->tcp_state > TCPS_BOUND)
796 (void) tcp_clean_death(((conn_t *)arg)->conn_tcp, ETIMEDOUT);
797 }
798
799 /*
800 * We are dying for some reason. Try to do it gracefully. (May be called
801 * as writer.)
802 *
803 * Return -1 if the structure was not cleaned up (if the cleanup had to be
804 * done by a service procedure).
805 * TBD - Should the return value distinguish between the tcp_t being
806 * freed and it being reinitialized?
807 */
808 int
809 tcp_clean_death(tcp_t *tcp, int err)
810 {
811 mblk_t *mp;
812 queue_t *q;
813 conn_t *connp = tcp->tcp_connp;
814 tcp_stack_t *tcps = tcp->tcp_tcps;
815
816 if (tcp->tcp_fused)
817 tcp_unfuse(tcp);
818
819 if (tcp->tcp_linger_tid != 0 &&
820 TCP_TIMER_CANCEL(tcp, tcp->tcp_linger_tid) >= 0) {
821 tcp_stop_lingering(tcp);
822 }
823
824 ASSERT(tcp != NULL);
825 ASSERT((connp->conn_family == AF_INET &&
826 connp->conn_ipversion == IPV4_VERSION) ||
827 (connp->conn_family == AF_INET6 &&
828 (connp->conn_ipversion == IPV4_VERSION ||
829 connp->conn_ipversion == IPV6_VERSION)));
830
831 if (TCP_IS_DETACHED(tcp)) {
832 if (tcp->tcp_hard_binding) {
833 /*
834 * Its an eager that we are dealing with. We close the
835 * eager but in case a conn_ind has already gone to the
836 * listener, let tcp_accept_finish() send a discon_ind
837 * to the listener and drop the last reference. If the
838 * listener doesn't even know about the eager i.e. the
839 * conn_ind hasn't gone up, blow away the eager and drop
840 * the last reference as well. If the conn_ind has gone
841 * up, state should be BOUND. tcp_accept_finish
842 * will figure out that the connection has received a
843 * RST and will send a DISCON_IND to the application.
844 */
845 tcp_closei_local(tcp);
846 if (!tcp->tcp_tconnind_started) {
847 CONN_DEC_REF(connp);
848 } else {
849 tcp->tcp_state = TCPS_BOUND;
850 DTRACE_TCP6(state__change, void, NULL,
851 ip_xmit_attr_t *, connp->conn_ixa,
852 void, NULL, tcp_t *, tcp, void, NULL,
853 int32_t, TCPS_CLOSED);
854 }
855 } else {
856 tcp_close_detached(tcp);
857 }
858 return (0);
859 }
860
861 TCP_STAT(tcps, tcp_clean_death_nondetached);
862
863 /*
864 * The connection is dead. Decrement listener connection counter if
865 * necessary.
866 */
867 if (tcp->tcp_listen_cnt != NULL)
868 TCP_DECR_LISTEN_CNT(tcp);
869
870 /*
871 * When a connection is moved to TIME_WAIT state, the connection
872 * counter is already decremented. So no need to decrement here
873 * again. See SET_TIME_WAIT() macro.
874 */
875 if (tcp->tcp_state >= TCPS_ESTABLISHED &&
876 tcp->tcp_state < TCPS_TIME_WAIT) {
877 TCPS_CONN_DEC(tcps);
878 }
879
880 q = connp->conn_rq;
881
882 /* Trash all inbound data */
883 if (!IPCL_IS_NONSTR(connp)) {
884 ASSERT(q != NULL);
885 flushq(q, FLUSHALL);
886 }
887
888 /*
889 * If we are at least part way open and there is error
890 * (err==0 implies no error)
891 * notify our client by a T_DISCON_IND.
892 */
893 if ((tcp->tcp_state >= TCPS_SYN_SENT) && err) {
894 if (tcp->tcp_state >= TCPS_ESTABLISHED &&
895 !TCP_IS_SOCKET(tcp)) {
896 /*
897 * Send M_FLUSH according to TPI. Because sockets will
898 * (and must) ignore FLUSHR we do that only for TPI
899 * endpoints and sockets in STREAMS mode.
900 */
901 (void) putnextctl1(q, M_FLUSH, FLUSHR);
902 }
903 if (connp->conn_debug) {
904 (void) strlog(TCP_MOD_ID, 0, 1, SL_TRACE|SL_ERROR,
905 "tcp_clean_death: discon err %d", err);
906 }
907 if (IPCL_IS_NONSTR(connp)) {
908 /* Direct socket, use upcall */
909 (*connp->conn_upcalls->su_disconnected)(
910 connp->conn_upper_handle, tcp->tcp_connid, err);
911 } else {
912 mp = mi_tpi_discon_ind(NULL, err, 0);
913 if (mp != NULL) {
914 putnext(q, mp);
915 } else {
916 if (connp->conn_debug) {
917 (void) strlog(TCP_MOD_ID, 0, 1,
918 SL_ERROR|SL_TRACE,
919 "tcp_clean_death, sending M_ERROR");
920 }
921 (void) putnextctl1(q, M_ERROR, EPROTO);
922 }
923 }
924 if (tcp->tcp_state <= TCPS_SYN_RCVD) {
925 /* SYN_SENT or SYN_RCVD */
926 TCPS_BUMP_MIB(tcps, tcpAttemptFails);
927 } else if (tcp->tcp_state <= TCPS_CLOSE_WAIT) {
928 /* ESTABLISHED or CLOSE_WAIT */
929 TCPS_BUMP_MIB(tcps, tcpEstabResets);
930 }
931 }
932
933 /*
934 * ESTABLISHED non-STREAMS eagers are not 'detached' because
935 * an upper handle is obtained when the SYN-ACK comes in. So it
936 * should receive the 'disconnected' upcall, but tcp_reinit should
937 * not be called since this is an eager.
938 */
939 if (tcp->tcp_listener != NULL && IPCL_IS_NONSTR(connp)) {
940 tcp_closei_local(tcp);
941 tcp->tcp_state = TCPS_BOUND;
942 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
943 connp->conn_ixa, void, NULL, tcp_t *, tcp, void, NULL,
944 int32_t, TCPS_CLOSED);
945 return (0);
946 }
947
948 tcp_reinit(tcp);
949 if (IPCL_IS_NONSTR(connp))
950 (void) tcp_do_unbind(connp);
951
952 return (-1);
953 }
954
955 /*
956 * In case tcp is in the "lingering state" and waits for the SO_LINGER timeout
957 * to expire, stop the wait and finish the close.
958 */
959 void
960 tcp_stop_lingering(tcp_t *tcp)
961 {
962 clock_t delta = 0;
963 tcp_stack_t *tcps = tcp->tcp_tcps;
964 conn_t *connp = tcp->tcp_connp;
965
966 tcp->tcp_linger_tid = 0;
967 if (tcp->tcp_state > TCPS_LISTEN) {
968 tcp_acceptor_hash_remove(tcp);
969 mutex_enter(&tcp->tcp_non_sq_lock);
970 if (tcp->tcp_flow_stopped) {
971 tcp_clrqfull(tcp);
972 }
973 mutex_exit(&tcp->tcp_non_sq_lock);
974
975 if (tcp->tcp_timer_tid != 0) {
976 delta = TCP_TIMER_CANCEL(tcp, tcp->tcp_timer_tid);
977 tcp->tcp_timer_tid = 0;
978 }
979 /*
980 * Need to cancel those timers which will not be used when
981 * TCP is detached. This has to be done before the conn_wq
982 * is cleared.
983 */
984 tcp_timers_stop(tcp);
985
986 tcp->tcp_detached = B_TRUE;
987 connp->conn_rq = NULL;
988 connp->conn_wq = NULL;
989
990 if (tcp->tcp_state == TCPS_TIME_WAIT) {
991 tcp_time_wait_append(tcp);
992 TCP_DBGSTAT(tcps, tcp_detach_time_wait);
993 goto finish;
994 }
995
996 /*
997 * If delta is zero the timer event wasn't executed and was
998 * successfully canceled. In this case we need to restart it
999 * with the minimal delta possible.
1000 */
1001 if (delta >= 0) {
1002 tcp->tcp_timer_tid = TCP_TIMER(tcp, tcp_timer,
1003 delta ? delta : 1);
1004 }
1005 } else {
1006 tcp_closei_local(tcp);
1007 CONN_DEC_REF(connp);
1008 }
1009 finish:
1010 tcp->tcp_detached = B_TRUE;
1011 connp->conn_rq = NULL;
1012 connp->conn_wq = NULL;
1013
1014 /* Signal closing thread that it can complete close */
1015 mutex_enter(&tcp->tcp_closelock);
1016 tcp->tcp_closed = 1;
1017 cv_signal(&tcp->tcp_closecv);
1018 mutex_exit(&tcp->tcp_closelock);
1019
1020 /* If we have an upper handle (socket), release it */
1021 if (IPCL_IS_NONSTR(connp)) {
1022 sock_upcalls_t *upcalls = connp->conn_upcalls;
1023 sock_upper_handle_t handle = connp->conn_upper_handle;
1024
1025 ASSERT(upcalls != NULL);
1026 ASSERT(upcalls->su_closed != NULL);
1027 ASSERT(handle != NULL);
1028 /*
1029 * Set these to NULL first because closed() will free upper
1030 * structures. Acquire conn_lock because an external caller
1031 * like conn_get_socket_info() will upcall if these are
1032 * non-NULL.
1033 */
1034 mutex_enter(&connp->conn_lock);
1035 connp->conn_upper_handle = NULL;
1036 connp->conn_upcalls = NULL;
1037 mutex_exit(&connp->conn_lock);
1038 upcalls->su_closed(handle);
1039 }
1040 }
1041
1042 void
1043 tcp_close_common(conn_t *connp, int flags)
1044 {
1045 tcp_t *tcp = connp->conn_tcp;
1046 mblk_t *mp = &tcp->tcp_closemp;
1047 boolean_t conn_ioctl_cleanup_reqd = B_FALSE;
1048 mblk_t *bp;
1049
1050 ASSERT(connp->conn_ref >= 2);
1051
1052 /*
1053 * Mark the conn as closing. ipsq_pending_mp_add will not
1054 * add any mp to the pending mp list, after this conn has
1055 * started closing.
1056 */
1057 mutex_enter(&connp->conn_lock);
1058 connp->conn_state_flags |= CONN_CLOSING;
1059 if (connp->conn_oper_pending_ill != NULL)
1060 conn_ioctl_cleanup_reqd = B_TRUE;
1061 CONN_INC_REF_LOCKED(connp);
1062 mutex_exit(&connp->conn_lock);
1063 tcp->tcp_closeflags = (uint8_t)flags;
1064 ASSERT(connp->conn_ref >= 3);
1065
1066 /*
1067 * tcp_closemp_used is used below without any protection of a lock
1068 * as we don't expect any one else to use it concurrently at this
1069 * point otherwise it would be a major defect.
1070 */
1071
1072 if (mp->b_prev == NULL)
1073 tcp->tcp_closemp_used = B_TRUE;
1074 else
1075 cmn_err(CE_PANIC, "tcp_close: concurrent use of tcp_closemp: "
1076 "connp %p tcp %p\n", (void *)connp, (void *)tcp);
1077
1078 TCP_DEBUG_GETPCSTACK(tcp->tcmp_stk, 15);
1079
1080 /*
1081 * Cleanup any queued ioctls here. This must be done before the wq/rq
1082 * are re-written by tcp_close_output().
1083 */
1084 if (conn_ioctl_cleanup_reqd)
1085 conn_ioctl_cleanup(connp);
1086
1087 /*
1088 * As CONN_CLOSING is set, no further ioctls should be passed down to
1089 * IP for this conn (see the guards in tcp_ioctl, tcp_wput_ioctl and
1090 * tcp_wput_iocdata). If the ioctl was queued on an ipsq,
1091 * conn_ioctl_cleanup should have found it and removed it. If the ioctl
1092 * was still in flight at the time, we wait for it here. See comments
1093 * for CONN_INC_IOCTLREF in ip.h for details.
1094 */
1095 mutex_enter(&connp->conn_lock);
1096 while (connp->conn_ioctlref > 0)
1097 cv_wait(&connp->conn_cv, &connp->conn_lock);
1098 ASSERT(connp->conn_ioctlref == 0);
1099 ASSERT(connp->conn_oper_pending_ill == NULL);
1100 mutex_exit(&connp->conn_lock);
1101
1102 SQUEUE_ENTER_ONE(connp->conn_sqp, mp, tcp_close_output, connp,
1103 NULL, tcp_squeue_flag, SQTAG_IP_TCP_CLOSE);
1104
1105 /*
1106 * For non-STREAMS sockets, the normal case is that the conn makes
1107 * an upcall when it's finally closed, so there is no need to wait
1108 * in the protocol. But in case of SO_LINGER the thread sleeps here
1109 * so it can properly deal with the thread being interrupted.
1110 */
1111 if (IPCL_IS_NONSTR(connp) && connp->conn_linger == 0)
1112 goto nowait;
1113
1114 mutex_enter(&tcp->tcp_closelock);
1115 while (!tcp->tcp_closed) {
1116 if (!cv_wait_sig(&tcp->tcp_closecv, &tcp->tcp_closelock)) {
1117 /*
1118 * The cv_wait_sig() was interrupted. We now do the
1119 * following:
1120 *
1121 * 1) If the endpoint was lingering, we allow this
1122 * to be interrupted by cancelling the linger timeout
1123 * and closing normally.
1124 *
1125 * 2) Revert to calling cv_wait()
1126 *
1127 * We revert to using cv_wait() to avoid an
1128 * infinite loop which can occur if the calling
1129 * thread is higher priority than the squeue worker
1130 * thread and is bound to the same cpu.
1131 */
1132 if (connp->conn_linger && connp->conn_lingertime > 0) {
1133 mutex_exit(&tcp->tcp_closelock);
1134 /* Entering squeue, bump ref count. */
1135 CONN_INC_REF(connp);
1136 bp = allocb_wait(0, BPRI_HI, STR_NOSIG, NULL);
1137 SQUEUE_ENTER_ONE(connp->conn_sqp, bp,
1138 tcp_linger_interrupted, connp, NULL,
1139 tcp_squeue_flag, SQTAG_IP_TCP_CLOSE);
1140 mutex_enter(&tcp->tcp_closelock);
1141 }
1142 break;
1143 }
1144 }
1145 while (!tcp->tcp_closed)
1146 cv_wait(&tcp->tcp_closecv, &tcp->tcp_closelock);
1147 mutex_exit(&tcp->tcp_closelock);
1148
1149 /*
1150 * In the case of listener streams that have eagers in the q or q0
1151 * we wait for the eagers to drop their reference to us. conn_rq and
1152 * conn_wq of the eagers point to our queues. By waiting for the
1153 * refcnt to drop to 1, we are sure that the eagers have cleaned
1154 * up their queue pointers and also dropped their references to us.
1155 *
1156 * For non-STREAMS sockets we do not have to wait here; the
1157 * listener will instead make a su_closed upcall when the last
1158 * reference is dropped.
1159 */
1160 if (tcp->tcp_wait_for_eagers && !IPCL_IS_NONSTR(connp)) {
1161 mutex_enter(&connp->conn_lock);
1162 while (connp->conn_ref != 1) {
1163 cv_wait(&connp->conn_cv, &connp->conn_lock);
1164 }
1165 mutex_exit(&connp->conn_lock);
1166 }
1167
1168 nowait:
1169 connp->conn_cpid = NOPID;
1170 }
1171
1172 /*
1173 * Called by tcp_close() routine via squeue when lingering is
1174 * interrupted by a signal.
1175 */
1176
1177 /* ARGSUSED */
1178 static void
1179 tcp_linger_interrupted(void *arg, mblk_t *mp, void *arg2, ip_recv_attr_t *dummy)
1180 {
1181 conn_t *connp = (conn_t *)arg;
1182 tcp_t *tcp = connp->conn_tcp;
1183
1184 freeb(mp);
1185 if (tcp->tcp_linger_tid != 0 &&
1186 TCP_TIMER_CANCEL(tcp, tcp->tcp_linger_tid) >= 0) {
1187 tcp_stop_lingering(tcp);
1188 tcp->tcp_client_errno = EINTR;
1189 }
1190 }
1191
1192 /*
1193 * Clean up the b_next and b_prev fields of every mblk pointed at by *mpp.
1194 * Some stream heads get upset if they see these later on as anything but NULL.
1195 */
1196 void
1197 tcp_close_mpp(mblk_t **mpp)
1198 {
1199 mblk_t *mp;
1200
1201 if ((mp = *mpp) != NULL) {
1202 do {
1203 mp->b_next = NULL;
1204 mp->b_prev = NULL;
1205 } while ((mp = mp->b_cont) != NULL);
1206
1207 mp = *mpp;
1208 *mpp = NULL;
1209 freemsg(mp);
1210 }
1211 }
1212
1213 /* Do detached close. */
1214 void
1215 tcp_close_detached(tcp_t *tcp)
1216 {
1217 if (tcp->tcp_fused)
1218 tcp_unfuse(tcp);
1219
1220 /*
1221 * Clustering code serializes TCP disconnect callbacks and
1222 * cluster tcp list walks by blocking a TCP disconnect callback
1223 * if a cluster tcp list walk is in progress. This ensures
1224 * accurate accounting of TCPs in the cluster code even though
1225 * the TCP list walk itself is not atomic.
1226 */
1227 tcp_closei_local(tcp);
1228 CONN_DEC_REF(tcp->tcp_connp);
1229 }
1230
1231 /*
1232 * The tcp_t is going away. Remove it from all lists and set it
1233 * to TCPS_CLOSED. The freeing up of memory is deferred until
1234 * tcp_inactive. This is needed since a thread in tcp_rput might have
1235 * done a CONN_INC_REF on this structure before it was removed from the
1236 * hashes.
1237 */
1238 void
1239 tcp_closei_local(tcp_t *tcp)
1240 {
1241 conn_t *connp = tcp->tcp_connp;
1242 tcp_stack_t *tcps = tcp->tcp_tcps;
1243 int32_t oldstate;
1244
1245 if (!TCP_IS_SOCKET(tcp))
1246 tcp_acceptor_hash_remove(tcp);
1247
1248 /*
1249 * This can be called via tcp_time_wait_processing() if TCP gets a
1250 * SYN with sequence number outside the TIME-WAIT connection's
1251 * window. So we need to check for TIME-WAIT state here as the
1252 * connection counter is already decremented. See SET_TIME_WAIT()
1253 * macro
1254 */
1255 if (tcp->tcp_state >= TCPS_ESTABLISHED &&
1256 tcp->tcp_state < TCPS_TIME_WAIT) {
1257 TCPS_CONN_DEC(tcps);
1258 }
1259
1260 /*
1261 * If we are an eager connection hanging off a listener that
1262 * hasn't formally accepted the connection yet, get off its
1263 * list and blow off any data that we have accumulated.
1264 */
1265 if (tcp->tcp_listener != NULL) {
1266 tcp_t *listener = tcp->tcp_listener;
1267 mutex_enter(&listener->tcp_eager_lock);
1268 /*
1269 * tcp_tconnind_started == B_TRUE means that the
1270 * conn_ind has already gone to listener. At
1271 * this point, eager will be closed but we
1272 * leave it in listeners eager list so that
1273 * if listener decides to close without doing
1274 * accept, we can clean this up. In tcp_tli_accept
1275 * we take care of the case of accept on closed
1276 * eager.
1277 */
1278 if (!tcp->tcp_tconnind_started) {
1279 tcp_eager_unlink(tcp);
1280 mutex_exit(&listener->tcp_eager_lock);
1281 /*
1282 * We don't want to have any pointers to the
1283 * listener queue, after we have released our
1284 * reference on the listener
1285 */
1286 ASSERT(tcp->tcp_detached);
1287 connp->conn_rq = NULL;
1288 connp->conn_wq = NULL;
1289 CONN_DEC_REF(listener->tcp_connp);
1290 } else {
1291 mutex_exit(&listener->tcp_eager_lock);
1292 }
1293 }
1294
1295 /* Stop all the timers */
1296 tcp_timers_stop(tcp);
1297
1298 if (tcp->tcp_state == TCPS_LISTEN) {
1299 if (tcp->tcp_ip_addr_cache) {
1300 kmem_free((void *)tcp->tcp_ip_addr_cache,
1301 IP_ADDR_CACHE_SIZE * sizeof (ipaddr_t));
1302 tcp->tcp_ip_addr_cache = NULL;
1303 }
1304 }
1305
1306 /* Decrement listerner connection counter if necessary. */
1307 if (tcp->tcp_listen_cnt != NULL)
1308 TCP_DECR_LISTEN_CNT(tcp);
1309
1310 mutex_enter(&tcp->tcp_non_sq_lock);
1311 if (tcp->tcp_flow_stopped)
1312 tcp_clrqfull(tcp);
1313 mutex_exit(&tcp->tcp_non_sq_lock);
1314
1315 tcp_bind_hash_remove(tcp);
1316 /*
1317 * If the tcp_time_wait_collector (which runs outside the squeue)
1318 * is trying to remove this tcp from the time wait list, we will
1319 * block in tcp_time_wait_remove while trying to acquire the
1320 * tcp_time_wait_lock. The logic in tcp_time_wait_collector also
1321 * requires the ipcl_hash_remove to be ordered after the
1322 * tcp_time_wait_remove for the refcnt checks to work correctly.
1323 */
1324 if (tcp->tcp_state == TCPS_TIME_WAIT)
1325 (void) tcp_time_wait_remove(tcp, NULL);
1326 CL_INET_DISCONNECT(connp);
1327 ipcl_hash_remove(connp);
1328 oldstate = tcp->tcp_state;
1329 tcp->tcp_state = TCPS_CLOSED;
1330 /* Need to probe before ixa_cleanup() is called */
1331 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
1332 connp->conn_ixa, void, NULL, tcp_t *, tcp, void, NULL,
1333 int32_t, oldstate);
1334 ixa_cleanup(connp->conn_ixa);
1335
1336 /*
1337 * Mark the conn as CONDEMNED
1338 */
1339 mutex_enter(&connp->conn_lock);
1340 connp->conn_state_flags |= CONN_CONDEMNED;
1341 mutex_exit(&connp->conn_lock);
1342
1343 ASSERT(tcp->tcp_time_wait_next == NULL);
1344 ASSERT(tcp->tcp_time_wait_prev == NULL);
1345 ASSERT(tcp->tcp_time_wait_expire == 0);
1346
1347 tcp_ipsec_cleanup(tcp);
1348 }
1349
1350 /*
1351 * tcp is dying (called from ipcl_conn_destroy and error cases).
1352 * Free the tcp_t in either case.
1353 */
1354 void
1355 tcp_free(tcp_t *tcp)
1356 {
1357 mblk_t *mp;
1358 conn_t *connp = tcp->tcp_connp;
1359
1360 ASSERT(tcp != NULL);
1361 ASSERT(tcp->tcp_ptpahn == NULL && tcp->tcp_acceptor_hash == NULL);
1362
1363 connp->conn_rq = NULL;
1364 connp->conn_wq = NULL;
1365
1366 tcp_close_mpp(&tcp->tcp_xmit_head);
1367 tcp_close_mpp(&tcp->tcp_reass_head);
1368 if (tcp->tcp_rcv_list != NULL) {
1369 /* Free b_next chain */
1370 tcp_close_mpp(&tcp->tcp_rcv_list);
1371 }
1372 if ((mp = tcp->tcp_urp_mp) != NULL) {
1373 freemsg(mp);
1374 }
1375 if ((mp = tcp->tcp_urp_mark_mp) != NULL) {
1376 freemsg(mp);
1377 }
1378
1379 if (tcp->tcp_fused_sigurg_mp != NULL) {
1380 ASSERT(!IPCL_IS_NONSTR(tcp->tcp_connp));
1381 freeb(tcp->tcp_fused_sigurg_mp);
1382 tcp->tcp_fused_sigurg_mp = NULL;
1383 }
1384
1385 if (tcp->tcp_ordrel_mp != NULL) {
1386 ASSERT(!IPCL_IS_NONSTR(tcp->tcp_connp));
1387 freeb(tcp->tcp_ordrel_mp);
1388 tcp->tcp_ordrel_mp = NULL;
1389 }
1390
1391 TCP_NOTSACK_REMOVE_ALL(tcp->tcp_notsack_list, tcp);
1392 bzero(&tcp->tcp_sack_info, sizeof (tcp_sack_info_t));
1393
1394 if (tcp->tcp_hopopts != NULL) {
1395 mi_free(tcp->tcp_hopopts);
1396 tcp->tcp_hopopts = NULL;
1397 tcp->tcp_hopoptslen = 0;
1398 }
1399 ASSERT(tcp->tcp_hopoptslen == 0);
1400 if (tcp->tcp_dstopts != NULL) {
1401 mi_free(tcp->tcp_dstopts);
1402 tcp->tcp_dstopts = NULL;
1403 tcp->tcp_dstoptslen = 0;
1404 }
1405 ASSERT(tcp->tcp_dstoptslen == 0);
1406 if (tcp->tcp_rthdrdstopts != NULL) {
1407 mi_free(tcp->tcp_rthdrdstopts);
1408 tcp->tcp_rthdrdstopts = NULL;
1409 tcp->tcp_rthdrdstoptslen = 0;
1410 }
1411 ASSERT(tcp->tcp_rthdrdstoptslen == 0);
1412 if (tcp->tcp_rthdr != NULL) {
1413 mi_free(tcp->tcp_rthdr);
1414 tcp->tcp_rthdr = NULL;
1415 tcp->tcp_rthdrlen = 0;
1416 }
1417 ASSERT(tcp->tcp_rthdrlen == 0);
1418
1419 /*
1420 * Following is really a blowing away a union.
1421 * It happens to have exactly two members of identical size
1422 * the following code is enough.
1423 */
1424 tcp_close_mpp(&tcp->tcp_conn.tcp_eager_conn_ind);
1425
1426 /* Allow the CC algorithm to clean up after itself. */
1427 if (tcp->tcp_cc_algo != NULL && tcp->tcp_cc_algo->cb_destroy != NULL)
1428 tcp->tcp_cc_algo->cb_destroy(&tcp->tcp_ccv);
1429
1430 /*
1431 * If this is a non-STREAM socket still holding on to an upper
1432 * handle, release it. As a result of fallback we might also see
1433 * STREAMS based conns with upper handles, in which case there is
1434 * nothing to do other than clearing the field.
1435 */
1436 if (connp->conn_upper_handle != NULL) {
1437 sock_upcalls_t *upcalls = connp->conn_upcalls;
1438 sock_upper_handle_t handle = connp->conn_upper_handle;
1439
1440 /*
1441 * Set these to NULL first because closed() will free upper
1442 * structures. Acquire conn_lock because an external caller
1443 * like conn_get_socket_info() will upcall if these are
1444 * non-NULL.
1445 */
1446 mutex_enter(&connp->conn_lock);
1447 connp->conn_upper_handle = NULL;
1448 connp->conn_upcalls = NULL;
1449 mutex_exit(&connp->conn_lock);
1450 if (IPCL_IS_NONSTR(connp)) {
1451 ASSERT(upcalls != NULL);
1452 ASSERT(upcalls->su_closed != NULL);
1453 ASSERT(handle != NULL);
1454 upcalls->su_closed(handle);
1455 tcp->tcp_detached = B_TRUE;
1456 }
1457 }
1458 }
1459
1460 /*
1461 * tcp_get_conn/tcp_free_conn
1462 *
1463 * tcp_get_conn is used to get a clean tcp connection structure.
1464 * It tries to reuse the connections put on the freelist by the
1465 * time_wait_collector failing which it goes to kmem_cache. This
1466 * way has two benefits compared to just allocating from and
1467 * freeing to kmem_cache.
1468 * 1) The time_wait_collector can free (which includes the cleanup)
1469 * outside the squeue. So when the interrupt comes, we have a clean
1470 * connection sitting in the freelist. Obviously, this buys us
1471 * performance.
1472 *
1473 * 2) Defence against DOS attack. Allocating a tcp/conn in tcp_input_listener
1474 * has multiple disadvantages - tying up the squeue during alloc.
1475 * But allocating the conn/tcp in IP land is also not the best since
1476 * we can't check the 'q' and 'q0' which are protected by squeue and
1477 * blindly allocate memory which might have to be freed here if we are
1478 * not allowed to accept the connection. By using the freelist and
1479 * putting the conn/tcp back in freelist, we don't pay a penalty for
1480 * allocating memory without checking 'q/q0' and freeing it if we can't
1481 * accept the connection.
1482 *
1483 * Care should be taken to put the conn back in the same squeue's freelist
1484 * from which it was allocated. Best results are obtained if conn is
1485 * allocated from listener's squeue and freed to the same. Time wait
1486 * collector will free up the freelist is the connection ends up sitting
1487 * there for too long.
1488 */
1489 conn_t *
1490 tcp_get_conn(void *arg, tcp_stack_t *tcps)
1491 {
1492 tcp_t *tcp = NULL;
1493 conn_t *connp = NULL;
1494 squeue_t *sqp = (squeue_t *)arg;
1495 tcp_squeue_priv_t *tcp_time_wait;
1496 netstack_t *ns;
1497 mblk_t *tcp_rsrv_mp = NULL;
1498
1499 tcp_time_wait =
1500 *((tcp_squeue_priv_t **)squeue_getprivate(sqp, SQPRIVATE_TCP));
1501
1502 mutex_enter(&tcp_time_wait->tcp_time_wait_lock);
1503 tcp = tcp_time_wait->tcp_free_list;
1504 ASSERT((tcp != NULL) ^ (tcp_time_wait->tcp_free_list_cnt == 0));
1505 if (tcp != NULL) {
1506 tcp_time_wait->tcp_free_list = tcp->tcp_time_wait_next;
1507 tcp_time_wait->tcp_free_list_cnt--;
1508 mutex_exit(&tcp_time_wait->tcp_time_wait_lock);
1509 tcp->tcp_time_wait_next = NULL;
1510 connp = tcp->tcp_connp;
1511 connp->conn_flags |= IPCL_REUSED;
1512
1513 ASSERT(tcp->tcp_tcps == NULL);
1514 ASSERT(connp->conn_netstack == NULL);
1515 ASSERT(tcp->tcp_rsrv_mp != NULL);
1516 ns = tcps->tcps_netstack;
1517 netstack_hold(ns);
1518 connp->conn_netstack = ns;
1519 connp->conn_ixa->ixa_ipst = ns->netstack_ip;
1520 tcp->tcp_tcps = tcps;
1521 ipcl_globalhash_insert(connp);
1522
1523 connp->conn_ixa->ixa_notify_cookie = tcp;
1524 ASSERT(connp->conn_ixa->ixa_notify == tcp_notify);
1525 connp->conn_recv = tcp_input_data;
1526 ASSERT(connp->conn_recvicmp == tcp_icmp_input);
1527 ASSERT(connp->conn_verifyicmp == tcp_verifyicmp);
1528 return (connp);
1529 }
1530 mutex_exit(&tcp_time_wait->tcp_time_wait_lock);
1531 /*
1532 * Pre-allocate the tcp_rsrv_mp. This mblk will not be freed until
1533 * this conn_t/tcp_t is freed at ipcl_conn_destroy().
1534 */
1535 tcp_rsrv_mp = allocb(0, BPRI_HI);
1536 if (tcp_rsrv_mp == NULL)
1537 return (NULL);
1538
1539 if ((connp = ipcl_conn_create(IPCL_TCPCONN, KM_NOSLEEP,
1540 tcps->tcps_netstack)) == NULL) {
1541 freeb(tcp_rsrv_mp);
1542 return (NULL);
1543 }
1544
1545 tcp = connp->conn_tcp;
1546 tcp->tcp_rsrv_mp = tcp_rsrv_mp;
1547 mutex_init(&tcp->tcp_rsrv_mp_lock, NULL, MUTEX_DEFAULT, NULL);
1548
1549 tcp->tcp_tcps = tcps;
1550
1551 connp->conn_recv = tcp_input_data;
1552 connp->conn_recvicmp = tcp_icmp_input;
1553 connp->conn_verifyicmp = tcp_verifyicmp;
1554
1555 /*
1556 * Register tcp_notify to listen to capability changes detected by IP.
1557 * This upcall is made in the context of the call to conn_ip_output
1558 * thus it is inside the squeue.
1559 */
1560 connp->conn_ixa->ixa_notify = tcp_notify;
1561 connp->conn_ixa->ixa_notify_cookie = tcp;
1562
1563 return (connp);
1564 }
1565
1566 /*
1567 * Handle connect to IPv4 destinations, including connections for AF_INET6
1568 * sockets connecting to IPv4 mapped IPv6 destinations.
1569 * Returns zero if OK, a positive errno, or a negative TLI error.
1570 */
1571 static int
1572 tcp_connect_ipv4(tcp_t *tcp, ipaddr_t *dstaddrp, in_port_t dstport,
1573 uint_t srcid)
1574 {
1575 ipaddr_t dstaddr = *dstaddrp;
1576 uint16_t lport;
1577 conn_t *connp = tcp->tcp_connp;
1578 tcp_stack_t *tcps = tcp->tcp_tcps;
1579 int error;
1580
1581 ASSERT(connp->conn_ipversion == IPV4_VERSION);
1582
1583 /* Check for attempt to connect to INADDR_ANY */
1584 if (dstaddr == INADDR_ANY) {
1585 /*
1586 * SunOS 4.x and 4.3 BSD allow an application
1587 * to connect a TCP socket to INADDR_ANY.
1588 * When they do this, the kernel picks the
1589 * address of one interface and uses it
1590 * instead. The kernel usually ends up
1591 * picking the address of the loopback
1592 * interface. This is an undocumented feature.
1593 * However, we provide the same thing here
1594 * in order to have source and binary
1595 * compatibility with SunOS 4.x.
1596 * Update the T_CONN_REQ (sin/sin6) since it is used to
1597 * generate the T_CONN_CON.
1598 */
1599 dstaddr = htonl(INADDR_LOOPBACK);
1600 *dstaddrp = dstaddr;
1601 }
1602
1603 /* Handle __sin6_src_id if socket not bound to an IP address */
1604 if (srcid != 0 && connp->conn_laddr_v4 == INADDR_ANY) {
1605 if (!ip_srcid_find_id(srcid, &connp->conn_laddr_v6,
1606 IPCL_ZONEID(connp), B_TRUE, tcps->tcps_netstack)) {
1607 /* Mismatch - conn_laddr_v6 would be v6 address. */
1608 return (EADDRNOTAVAIL);
1609 }
1610 connp->conn_saddr_v6 = connp->conn_laddr_v6;
1611 }
1612
1613 IN6_IPADDR_TO_V4MAPPED(dstaddr, &connp->conn_faddr_v6);
1614 connp->conn_fport = dstport;
1615
1616 /*
1617 * At this point the remote destination address and remote port fields
1618 * in the tcp-four-tuple have been filled in the tcp structure. Now we
1619 * have to see which state tcp was in so we can take appropriate action.
1620 */
1621 if (tcp->tcp_state == TCPS_IDLE) {
1622 /*
1623 * We support a quick connect capability here, allowing
1624 * clients to transition directly from IDLE to SYN_SENT
1625 * tcp_bindi will pick an unused port, insert the connection
1626 * in the bind hash and transition to BOUND state.
1627 */
1628 lport = tcp_update_next_port(tcps->tcps_next_port_to_try,
1629 tcp, B_TRUE);
1630 lport = tcp_bindi(tcp, lport, &connp->conn_laddr_v6, 0, B_TRUE,
1631 B_FALSE, B_FALSE);
1632 if (lport == 0)
1633 return (-TNOADDR);
1634 }
1635
1636 /*
1637 * Lookup the route to determine a source address and the uinfo.
1638 * Setup TCP parameters based on the metrics/DCE.
1639 */
1640 error = tcp_set_destination(tcp);
1641 if (error != 0)
1642 return (error);
1643
1644 /*
1645 * Don't let an endpoint connect to itself.
1646 */
1647 if (connp->conn_faddr_v4 == connp->conn_laddr_v4 &&
1648 connp->conn_fport == connp->conn_lport)
1649 return (-TBADADDR);
1650
1651 tcp->tcp_state = TCPS_SYN_SENT;
1652
1653 return (ipcl_conn_insert_v4(connp));
1654 }
1655
1656 /*
1657 * Handle connect to IPv6 destinations.
1658 * Returns zero if OK, a positive errno, or a negative TLI error.
1659 */
1660 static int
1661 tcp_connect_ipv6(tcp_t *tcp, in6_addr_t *dstaddrp, in_port_t dstport,
1662 uint32_t flowinfo, uint_t srcid, uint32_t scope_id)
1663 {
1664 uint16_t lport;
1665 conn_t *connp = tcp->tcp_connp;
1666 tcp_stack_t *tcps = tcp->tcp_tcps;
1667 int error;
1668
1669 ASSERT(connp->conn_family == AF_INET6);
1670
1671 /*
1672 * If we're here, it means that the destination address is a native
1673 * IPv6 address. Return an error if conn_ipversion is not IPv6. A
1674 * reason why it might not be IPv6 is if the socket was bound to an
1675 * IPv4-mapped IPv6 address.
1676 */
1677 if (connp->conn_ipversion != IPV6_VERSION)
1678 return (-TBADADDR);
1679
1680 /*
1681 * Interpret a zero destination to mean loopback.
1682 * Update the T_CONN_REQ (sin/sin6) since it is used to
1683 * generate the T_CONN_CON.
1684 */
1685 if (IN6_IS_ADDR_UNSPECIFIED(dstaddrp))
1686 *dstaddrp = ipv6_loopback;
1687
1688 /* Handle __sin6_src_id if socket not bound to an IP address */
1689 if (srcid != 0 && IN6_IS_ADDR_UNSPECIFIED(&connp->conn_laddr_v6)) {
1690 if (!ip_srcid_find_id(srcid, &connp->conn_laddr_v6,
1691 IPCL_ZONEID(connp), B_FALSE, tcps->tcps_netstack)) {
1692 /* Mismatch - conn_laddr_v6 would be v4-mapped. */
1693 return (EADDRNOTAVAIL);
1694 }
1695 connp->conn_saddr_v6 = connp->conn_laddr_v6;
1696 }
1697
1698 /*
1699 * Take care of the scope_id now.
1700 */
1701 if (scope_id != 0 && IN6_IS_ADDR_LINKSCOPE(dstaddrp)) {
1702 connp->conn_ixa->ixa_flags |= IXAF_SCOPEID_SET;
1703 connp->conn_ixa->ixa_scopeid = scope_id;
1704 } else {
1705 connp->conn_ixa->ixa_flags &= ~IXAF_SCOPEID_SET;
1706 }
1707
1708 connp->conn_flowinfo = flowinfo;
1709 connp->conn_faddr_v6 = *dstaddrp;
1710 connp->conn_fport = dstport;
1711
1712 /*
1713 * At this point the remote destination address and remote port fields
1714 * in the tcp-four-tuple have been filled in the tcp structure. Now we
1715 * have to see which state tcp was in so we can take appropriate action.
1716 */
1717 if (tcp->tcp_state == TCPS_IDLE) {
1718 /*
1719 * We support a quick connect capability here, allowing
1720 * clients to transition directly from IDLE to SYN_SENT
1721 * tcp_bindi will pick an unused port, insert the connection
1722 * in the bind hash and transition to BOUND state.
1723 */
1724 lport = tcp_update_next_port(tcps->tcps_next_port_to_try,
1725 tcp, B_TRUE);
1726 lport = tcp_bindi(tcp, lport, &connp->conn_laddr_v6, 0, B_TRUE,
1727 B_FALSE, B_FALSE);
1728 if (lport == 0)
1729 return (-TNOADDR);
1730 }
1731
1732 /*
1733 * Lookup the route to determine a source address and the uinfo.
1734 * Setup TCP parameters based on the metrics/DCE.
1735 */
1736 error = tcp_set_destination(tcp);
1737 if (error != 0)
1738 return (error);
1739
1740 /*
1741 * Don't let an endpoint connect to itself.
1742 */
1743 if (IN6_ARE_ADDR_EQUAL(&connp->conn_faddr_v6, &connp->conn_laddr_v6) &&
1744 connp->conn_fport == connp->conn_lport)
1745 return (-TBADADDR);
1746
1747 tcp->tcp_state = TCPS_SYN_SENT;
1748
1749 return (ipcl_conn_insert_v6(connp));
1750 }
1751
1752 /*
1753 * Disconnect
1754 * Note that unlike other functions this returns a positive tli error
1755 * when it fails; it never returns an errno.
1756 */
1757 static int
1758 tcp_disconnect_common(tcp_t *tcp, t_scalar_t seqnum)
1759 {
1760 conn_t *lconnp;
1761 tcp_stack_t *tcps = tcp->tcp_tcps;
1762 conn_t *connp = tcp->tcp_connp;
1763
1764 /*
1765 * Right now, upper modules pass down a T_DISCON_REQ to TCP,
1766 * when the stream is in BOUND state. Do not send a reset,
1767 * since the destination IP address is not valid, and it can
1768 * be the initialized value of all zeros (broadcast address).
1769 */
1770 if (tcp->tcp_state <= TCPS_BOUND) {
1771 if (connp->conn_debug) {
1772 (void) strlog(TCP_MOD_ID, 0, 1, SL_ERROR|SL_TRACE,
1773 "tcp_disconnect: bad state, %d", tcp->tcp_state);
1774 }
1775 return (TOUTSTATE);
1776 } else if (tcp->tcp_state >= TCPS_ESTABLISHED) {
1777 TCPS_CONN_DEC(tcps);
1778 }
1779
1780 if (seqnum == -1 || tcp->tcp_conn_req_max == 0) {
1781
1782 /*
1783 * According to TPI, for non-listeners, ignore seqnum
1784 * and disconnect.
1785 * Following interpretation of -1 seqnum is historical
1786 * and implied TPI ? (TPI only states that for T_CONN_IND,
1787 * a valid seqnum should not be -1).
1788 *
1789 * -1 means disconnect everything
1790 * regardless even on a listener.
1791 */
1792
1793 int old_state = tcp->tcp_state;
1794 ip_stack_t *ipst = tcps->tcps_netstack->netstack_ip;
1795
1796 /*
1797 * The connection can't be on the tcp_time_wait_head list
1798 * since it is not detached.
1799 */
1800 ASSERT(tcp->tcp_time_wait_next == NULL);
1801 ASSERT(tcp->tcp_time_wait_prev == NULL);
1802 ASSERT(tcp->tcp_time_wait_expire == 0);
1803 /*
1804 * If it used to be a listener, check to make sure no one else
1805 * has taken the port before switching back to LISTEN state.
1806 */
1807 if (connp->conn_ipversion == IPV4_VERSION) {
1808 lconnp = ipcl_lookup_listener_v4(connp->conn_lport,
1809 connp->conn_laddr_v4, IPCL_ZONEID(connp), ipst);
1810 } else {
1811 uint_t ifindex = 0;
1812
1813 if (connp->conn_ixa->ixa_flags & IXAF_SCOPEID_SET)
1814 ifindex = connp->conn_ixa->ixa_scopeid;
1815
1816 /* Allow conn_bound_if listeners? */
1817 lconnp = ipcl_lookup_listener_v6(connp->conn_lport,
1818 &connp->conn_laddr_v6, ifindex, IPCL_ZONEID(connp),
1819 ipst);
1820 }
1821 if (tcp->tcp_conn_req_max && lconnp == NULL) {
1822 tcp->tcp_state = TCPS_LISTEN;
1823 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
1824 connp->conn_ixa, void, NULL, tcp_t *, tcp, void,
1825 NULL, int32_t, old_state);
1826 } else if (old_state > TCPS_BOUND) {
1827 tcp->tcp_conn_req_max = 0;
1828 tcp->tcp_state = TCPS_BOUND;
1829 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
1830 connp->conn_ixa, void, NULL, tcp_t *, tcp, void,
1831 NULL, int32_t, old_state);
1832
1833 /*
1834 * If this end point is not going to become a listener,
1835 * decrement the listener connection count if
1836 * necessary. Note that we do not do this if it is
1837 * going to be a listner (the above if case) since
1838 * then it may remove the counter struct.
1839 */
1840 if (tcp->tcp_listen_cnt != NULL)
1841 TCP_DECR_LISTEN_CNT(tcp);
1842 }
1843 if (lconnp != NULL)
1844 CONN_DEC_REF(lconnp);
1845 switch (old_state) {
1846 case TCPS_SYN_SENT:
1847 case TCPS_SYN_RCVD:
1848 TCPS_BUMP_MIB(tcps, tcpAttemptFails);
1849 break;
1850 case TCPS_ESTABLISHED:
1851 case TCPS_CLOSE_WAIT:
1852 TCPS_BUMP_MIB(tcps, tcpEstabResets);
1853 break;
1854 }
1855
1856 if (tcp->tcp_fused)
1857 tcp_unfuse(tcp);
1858
1859 mutex_enter(&tcp->tcp_eager_lock);
1860 if ((tcp->tcp_conn_req_cnt_q0 != 0) ||
1861 (tcp->tcp_conn_req_cnt_q != 0)) {
1862 tcp_eager_cleanup(tcp, 0);
1863 }
1864 mutex_exit(&tcp->tcp_eager_lock);
1865
1866 tcp_xmit_ctl("tcp_disconnect", tcp, tcp->tcp_snxt,
1867 tcp->tcp_rnxt, TH_RST | TH_ACK);
1868
1869 tcp_reinit(tcp);
1870
1871 return (0);
1872 } else if (!tcp_eager_blowoff(tcp, seqnum)) {
1873 return (TBADSEQ);
1874 }
1875 return (0);
1876 }
1877
1878 /*
1879 * Our client hereby directs us to reject the connection request
1880 * that tcp_input_listener() marked with 'seqnum'. Rejection consists
1881 * of sending the appropriate RST, not an ICMP error.
1882 */
1883 void
1884 tcp_disconnect(tcp_t *tcp, mblk_t *mp)
1885 {
1886 t_scalar_t seqnum;
1887 int error;
1888 conn_t *connp = tcp->tcp_connp;
1889
1890 ASSERT((uintptr_t)(mp->b_wptr - mp->b_rptr) <= (uintptr_t)INT_MAX);
1891 if ((mp->b_wptr - mp->b_rptr) < sizeof (struct T_discon_req)) {
1892 tcp_err_ack(tcp, mp, TPROTO, 0);
1893 return;
1894 }
1895 seqnum = ((struct T_discon_req *)mp->b_rptr)->SEQ_number;
1896 error = tcp_disconnect_common(tcp, seqnum);
1897 if (error != 0)
1898 tcp_err_ack(tcp, mp, error, 0);
1899 else {
1900 if (tcp->tcp_state >= TCPS_ESTABLISHED) {
1901 /* Send M_FLUSH according to TPI */
1902 (void) putnextctl1(connp->conn_rq, M_FLUSH, FLUSHRW);
1903 }
1904 mp = mi_tpi_ok_ack_alloc(mp);
1905 if (mp != NULL)
1906 putnext(connp->conn_rq, mp);
1907 }
1908 }
1909
1910 /*
1911 * Handle reinitialization of a tcp structure.
1912 * Maintain "binding state" resetting the state to BOUND, LISTEN, or IDLE.
1913 */
1914 static void
1915 tcp_reinit(tcp_t *tcp)
1916 {
1917 mblk_t *mp;
1918 tcp_stack_t *tcps = tcp->tcp_tcps;
1919 conn_t *connp = tcp->tcp_connp;
1920 int32_t oldstate;
1921
1922 /* tcp_reinit should never be called for detached tcp_t's */
1923 ASSERT(tcp->tcp_listener == NULL);
1924 ASSERT((connp->conn_family == AF_INET &&
1925 connp->conn_ipversion == IPV4_VERSION) ||
1926 (connp->conn_family == AF_INET6 &&
1927 (connp->conn_ipversion == IPV4_VERSION ||
1928 connp->conn_ipversion == IPV6_VERSION)));
1929
1930 /* Cancel outstanding timers */
1931 tcp_timers_stop(tcp);
1932
1933 tcp_close_mpp(&tcp->tcp_xmit_head);
1934 if (tcp->tcp_snd_zcopy_aware)
1935 tcp_zcopy_notify(tcp);
1936 tcp->tcp_xmit_last = tcp->tcp_xmit_tail = NULL;
1937 tcp->tcp_unsent = tcp->tcp_xmit_tail_unsent = 0;
1938 mutex_enter(&tcp->tcp_non_sq_lock);
1939 if (tcp->tcp_flow_stopped &&
1940 TCP_UNSENT_BYTES(tcp) <= connp->conn_sndlowat) {
1941 tcp_clrqfull(tcp);
1942 }
1943 mutex_exit(&tcp->tcp_non_sq_lock);
1944 tcp_close_mpp(&tcp->tcp_reass_head);
1945 tcp->tcp_reass_tail = NULL;
1946 if (tcp->tcp_rcv_list != NULL) {
1947 /* Free b_next chain */
1948 tcp_close_mpp(&tcp->tcp_rcv_list);
1949 tcp->tcp_rcv_last_head = NULL;
1950 tcp->tcp_rcv_last_tail = NULL;
1951 tcp->tcp_rcv_cnt = 0;
1952 }
1953 tcp->tcp_rcv_last_tail = NULL;
1954
1955 if ((mp = tcp->tcp_urp_mp) != NULL) {
1956 freemsg(mp);
1957 tcp->tcp_urp_mp = NULL;
1958 }
1959 if ((mp = tcp->tcp_urp_mark_mp) != NULL) {
1960 freemsg(mp);
1961 tcp->tcp_urp_mark_mp = NULL;
1962 }
1963 if (tcp->tcp_fused_sigurg_mp != NULL) {
1964 ASSERT(!IPCL_IS_NONSTR(tcp->tcp_connp));
1965 freeb(tcp->tcp_fused_sigurg_mp);
1966 tcp->tcp_fused_sigurg_mp = NULL;
1967 }
1968 if (tcp->tcp_ordrel_mp != NULL) {
1969 ASSERT(!IPCL_IS_NONSTR(tcp->tcp_connp));
1970 freeb(tcp->tcp_ordrel_mp);
1971 tcp->tcp_ordrel_mp = NULL;
1972 }
1973
1974 /*
1975 * Following is a union with two members which are
1976 * identical types and size so the following cleanup
1977 * is enough.
1978 */
1979 tcp_close_mpp(&tcp->tcp_conn.tcp_eager_conn_ind);
1980
1981 CL_INET_DISCONNECT(connp);
1982
1983 /*
1984 * The connection can't be on the tcp_time_wait_head list
1985 * since it is not detached.
1986 */
1987 ASSERT(tcp->tcp_time_wait_next == NULL);
1988 ASSERT(tcp->tcp_time_wait_prev == NULL);
1989 ASSERT(tcp->tcp_time_wait_expire == 0);
1990
1991 /*
1992 * Reset/preserve other values
1993 */
1994 tcp_reinit_values(tcp);
1995 ipcl_hash_remove(connp);
1996 /* Note that ixa_cred gets cleared in ixa_cleanup */
1997 ixa_cleanup(connp->conn_ixa);
1998 tcp_ipsec_cleanup(tcp);
1999
2000 connp->conn_laddr_v6 = connp->conn_bound_addr_v6;
2001 connp->conn_saddr_v6 = connp->conn_bound_addr_v6;
2002 oldstate = tcp->tcp_state;
2003
2004 if (tcp->tcp_conn_req_max != 0) {
2005 /*
2006 * This is the case when a TLI program uses the same
2007 * transport end point to accept a connection. This
2008 * makes the TCP both a listener and acceptor. When
2009 * this connection is closed, we need to set the state
2010 * back to TCPS_LISTEN. Make sure that the eager list
2011 * is reinitialized.
2012 *
2013 * Note that this stream is still bound to the four
2014 * tuples of the previous connection in IP. If a new
2015 * SYN with different foreign address comes in, IP will
2016 * not find it and will send it to the global queue. In
2017 * the global queue, TCP will do a tcp_lookup_listener()
2018 * to find this stream. This works because this stream
2019 * is only removed from connected hash.
2020 *
2021 */
2022 tcp->tcp_state = TCPS_LISTEN;
2023 tcp->tcp_eager_next_q0 = tcp->tcp_eager_prev_q0 = tcp;
2024 tcp->tcp_eager_next_drop_q0 = tcp;
2025 tcp->tcp_eager_prev_drop_q0 = tcp;
2026 /*
2027 * Initially set conn_recv to tcp_input_listener_unbound to try
2028 * to pick a good squeue for the listener when the first SYN
2029 * arrives. tcp_input_listener_unbound sets it to
2030 * tcp_input_listener on that first SYN.
2031 */
2032 connp->conn_recv = tcp_input_listener_unbound;
2033
2034 connp->conn_proto = IPPROTO_TCP;
2035 connp->conn_faddr_v6 = ipv6_all_zeros;
2036 connp->conn_fport = 0;
2037
2038 (void) ipcl_bind_insert(connp);
2039 } else {
2040 tcp->tcp_state = TCPS_BOUND;
2041 }
2042
2043 /*
2044 * Initialize to default values
2045 */
2046 tcp_init_values(tcp, NULL);
2047
2048 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
2049 connp->conn_ixa, void, NULL, tcp_t *, tcp, void, NULL,
2050 int32_t, oldstate);
2051
2052 ASSERT(tcp->tcp_ptpbhn != NULL);
2053 tcp->tcp_rwnd = connp->conn_rcvbuf;
2054 tcp->tcp_mss = connp->conn_ipversion != IPV4_VERSION ?
2055 tcps->tcps_mss_def_ipv6 : tcps->tcps_mss_def_ipv4;
2056 }
2057
2058 /*
2059 * Force values to zero that need be zero.
2060 * Do not touch values asociated with the BOUND or LISTEN state
2061 * since the connection will end up in that state after the reinit.
2062 * NOTE: tcp_reinit_values MUST have a line for each field in the tcp_t
2063 * structure!
2064 */
2065 static void
2066 tcp_reinit_values(tcp_t *tcp)
2067 {
2068 tcp_stack_t *tcps = tcp->tcp_tcps;
2069 conn_t *connp = tcp->tcp_connp;
2070
2071 #ifndef lint
2072 #define DONTCARE(x)
2073 #define PRESERVE(x)
2074 #else
2075 #define DONTCARE(x) ((x) = (x))
2076 #define PRESERVE(x) ((x) = (x))
2077 #endif /* lint */
2078
2079 PRESERVE(tcp->tcp_bind_hash_port);
2080 PRESERVE(tcp->tcp_bind_hash);
2081 PRESERVE(tcp->tcp_ptpbhn);
2082 PRESERVE(tcp->tcp_acceptor_hash);
2083 PRESERVE(tcp->tcp_ptpahn);
2084
2085 /* Should be ASSERT NULL on these with new code! */
2086 ASSERT(tcp->tcp_time_wait_next == NULL);
2087 ASSERT(tcp->tcp_time_wait_prev == NULL);
2088 ASSERT(tcp->tcp_time_wait_expire == 0);
2089 PRESERVE(tcp->tcp_state);
2090 PRESERVE(connp->conn_rq);
2091 PRESERVE(connp->conn_wq);
2092
2093 ASSERT(tcp->tcp_xmit_head == NULL);
2094 ASSERT(tcp->tcp_xmit_last == NULL);
2095 ASSERT(tcp->tcp_unsent == 0);
2096 ASSERT(tcp->tcp_xmit_tail == NULL);
2097 ASSERT(tcp->tcp_xmit_tail_unsent == 0);
2098
2099 tcp->tcp_snxt = 0; /* Displayed in mib */
2100 tcp->tcp_suna = 0; /* Displayed in mib */
2101 tcp->tcp_swnd = 0;
2102 DONTCARE(tcp->tcp_cwnd); /* Init in tcp_process_options */
2103
2104 if (connp->conn_ht_iphc != NULL) {
2105 kmem_free(connp->conn_ht_iphc, connp->conn_ht_iphc_allocated);
2106 connp->conn_ht_iphc = NULL;
2107 connp->conn_ht_iphc_allocated = 0;
2108 connp->conn_ht_iphc_len = 0;
2109 connp->conn_ht_ulp = NULL;
2110 connp->conn_ht_ulp_len = 0;
2111 tcp->tcp_ipha = NULL;
2112 tcp->tcp_ip6h = NULL;
2113 tcp->tcp_tcpha = NULL;
2114 }
2115
2116 /* We clear any IP_OPTIONS and extension headers */
2117 ip_pkt_free(&connp->conn_xmit_ipp);
2118
2119 DONTCARE(tcp->tcp_naglim); /* Init in tcp_init_values */
2120 DONTCARE(tcp->tcp_ipha);
2121 DONTCARE(tcp->tcp_ip6h);
2122 DONTCARE(tcp->tcp_tcpha);
2123 tcp->tcp_valid_bits = 0;
2124
2125 DONTCARE(tcp->tcp_timer_backoff); /* Init in tcp_init_values */
2126 DONTCARE(tcp->tcp_last_recv_time); /* Init in tcp_init_values */
2127 tcp->tcp_last_rcv_lbolt = 0;
2128
2129 tcp->tcp_init_cwnd = 0;
2130
2131 tcp->tcp_urp_last_valid = 0;
2132 tcp->tcp_hard_binding = 0;
2133
2134 tcp->tcp_fin_acked = 0;
2135 tcp->tcp_fin_rcvd = 0;
2136 tcp->tcp_fin_sent = 0;
2137 tcp->tcp_ordrel_done = 0;
2138
2139 tcp->tcp_detached = 0;
2140
2141 tcp->tcp_snd_ws_ok = B_FALSE;
2142 tcp->tcp_snd_ts_ok = B_FALSE;
2143 tcp->tcp_zero_win_probe = 0;
2144
2145 tcp->tcp_loopback = 0;
2146 tcp->tcp_localnet = 0;
2147 tcp->tcp_syn_defense = 0;
2148 tcp->tcp_set_timer = 0;
2149
2150 tcp->tcp_active_open = 0;
2151 tcp->tcp_rexmit = B_FALSE;
2152 tcp->tcp_xmit_zc_clean = B_FALSE;
2153
2154 tcp->tcp_snd_sack_ok = B_FALSE;
2155 tcp->tcp_hwcksum = B_FALSE;
2156
2157 DONTCARE(tcp->tcp_maxpsz_multiplier); /* Init in tcp_init_values */
2158
2159 tcp->tcp_conn_def_q0 = 0;
2160 tcp->tcp_ip_forward_progress = B_FALSE;
2161 tcp->tcp_ecn_ok = B_FALSE;
2162
2163 tcp->tcp_cwr = B_FALSE;
2164 tcp->tcp_ecn_echo_on = B_FALSE;
2165 tcp->tcp_is_wnd_shrnk = B_FALSE;
2166
2167 TCP_NOTSACK_REMOVE_ALL(tcp->tcp_notsack_list, tcp);
2168 bzero(&tcp->tcp_sack_info, sizeof (tcp_sack_info_t));
2169
2170 tcp->tcp_rcv_ws = 0;
2171 tcp->tcp_snd_ws = 0;
2172 tcp->tcp_ts_recent = 0;
2173 tcp->tcp_rnxt = 0; /* Displayed in mib */
2174 DONTCARE(tcp->tcp_rwnd); /* Set in tcp_reinit() */
2175 tcp->tcp_initial_pmtu = 0;
2176
2177 ASSERT(tcp->tcp_reass_head == NULL);
2178 ASSERT(tcp->tcp_reass_tail == NULL);
2179
2180 tcp->tcp_cwnd_cnt = 0;
2181
2182 ASSERT(tcp->tcp_rcv_list == NULL);
2183 ASSERT(tcp->tcp_rcv_last_head == NULL);
2184 ASSERT(tcp->tcp_rcv_last_tail == NULL);
2185 ASSERT(tcp->tcp_rcv_cnt == 0);
2186
2187 DONTCARE(tcp->tcp_cwnd_ssthresh); /* Init in tcp_set_destination */
2188 DONTCARE(tcp->tcp_cwnd_max); /* Init in tcp_init_values */
2189 tcp->tcp_csuna = 0;
2190
2191 tcp->tcp_rto = 0; /* Displayed in MIB */
2192 DONTCARE(tcp->tcp_rtt_sa); /* Init in tcp_init_values */
2193 DONTCARE(tcp->tcp_rtt_sd); /* Init in tcp_init_values */
2194 tcp->tcp_rtt_update = 0;
2195 tcp->tcp_rtt_sum = 0;
2196 tcp->tcp_rtt_cnt = 0;
2197
2198 DONTCARE(tcp->tcp_swl1); /* Init in case TCPS_LISTEN/TCPS_SYN_SENT */
2199 DONTCARE(tcp->tcp_swl2); /* Init in case TCPS_LISTEN/TCPS_SYN_SENT */
2200
2201 tcp->tcp_rack = 0; /* Displayed in mib */
2202 tcp->tcp_rack_cnt = 0;
2203 tcp->tcp_rack_cur_max = 0;
2204 tcp->tcp_rack_abs_max = 0;
2205
2206 tcp->tcp_max_swnd = 0;
2207
2208 ASSERT(tcp->tcp_listener == NULL);
2209
2210 DONTCARE(tcp->tcp_irs); /* tcp_valid_bits cleared */
2211 DONTCARE(tcp->tcp_iss); /* tcp_valid_bits cleared */
2212 DONTCARE(tcp->tcp_fss); /* tcp_valid_bits cleared */
2213 DONTCARE(tcp->tcp_urg); /* tcp_valid_bits cleared */
2214
2215 ASSERT(tcp->tcp_conn_req_cnt_q == 0);
2216 ASSERT(tcp->tcp_conn_req_cnt_q0 == 0);
2217 PRESERVE(tcp->tcp_conn_req_max);
2218 PRESERVE(tcp->tcp_conn_req_seqnum);
2219
2220 DONTCARE(tcp->tcp_first_timer_threshold); /* Init in tcp_init_values */
2221 DONTCARE(tcp->tcp_second_timer_threshold); /* Init in tcp_init_values */
2222 DONTCARE(tcp->tcp_first_ctimer_threshold); /* Init in tcp_init_values */
2223 DONTCARE(tcp->tcp_second_ctimer_threshold); /* in tcp_init_values */
2224
2225 DONTCARE(tcp->tcp_urp_last); /* tcp_urp_last_valid is cleared */
2226 ASSERT(tcp->tcp_urp_mp == NULL);
2227 ASSERT(tcp->tcp_urp_mark_mp == NULL);
2228 ASSERT(tcp->tcp_fused_sigurg_mp == NULL);
2229
2230 ASSERT(tcp->tcp_eager_next_q == NULL);
2231 ASSERT(tcp->tcp_eager_last_q == NULL);
2232 ASSERT((tcp->tcp_eager_next_q0 == NULL &&
2233 tcp->tcp_eager_prev_q0 == NULL) ||
2234 tcp->tcp_eager_next_q0 == tcp->tcp_eager_prev_q0);
2235 ASSERT(tcp->tcp_conn.tcp_eager_conn_ind == NULL);
2236
2237 ASSERT((tcp->tcp_eager_next_drop_q0 == NULL &&
2238 tcp->tcp_eager_prev_drop_q0 == NULL) ||
2239 tcp->tcp_eager_next_drop_q0 == tcp->tcp_eager_prev_drop_q0);
2240
2241 DONTCARE(tcp->tcp_ka_rinterval); /* Init in tcp_init_values */
2242 DONTCARE(tcp->tcp_ka_abort_thres); /* Init in tcp_init_values */
2243 DONTCARE(tcp->tcp_ka_cnt); /* Init in tcp_init_values */
2244
2245 tcp->tcp_client_errno = 0;
2246
2247 DONTCARE(connp->conn_sum); /* Init in tcp_init_values */
2248
2249 connp->conn_faddr_v6 = ipv6_all_zeros; /* Displayed in MIB */
2250
2251 PRESERVE(connp->conn_bound_addr_v6);
2252 tcp->tcp_last_sent_len = 0;
2253 tcp->tcp_dupack_cnt = 0;
2254
2255 connp->conn_fport = 0; /* Displayed in MIB */
2256 PRESERVE(connp->conn_lport);
2257
2258 PRESERVE(tcp->tcp_acceptor_lockp);
2259
2260 ASSERT(tcp->tcp_ordrel_mp == NULL);
2261 PRESERVE(tcp->tcp_acceptor_id);
2262 DONTCARE(tcp->tcp_ipsec_overhead);
2263
2264 PRESERVE(connp->conn_family);
2265 /* Remove any remnants of mapped address binding */
2266 if (connp->conn_family == AF_INET6) {
2267 connp->conn_ipversion = IPV6_VERSION;
2268 tcp->tcp_mss = tcps->tcps_mss_def_ipv6;
2269 } else {
2270 connp->conn_ipversion = IPV4_VERSION;
2271 tcp->tcp_mss = tcps->tcps_mss_def_ipv4;
2272 }
2273
2274 connp->conn_bound_if = 0;
2275 connp->conn_recv_ancillary.crb_all = 0;
2276 tcp->tcp_recvifindex = 0;
2277 tcp->tcp_recvhops = 0;
2278 tcp->tcp_closed = 0;
2279 if (tcp->tcp_hopopts != NULL) {
2280 mi_free(tcp->tcp_hopopts);
2281 tcp->tcp_hopopts = NULL;
2282 tcp->tcp_hopoptslen = 0;
2283 }
2284 ASSERT(tcp->tcp_hopoptslen == 0);
2285 if (tcp->tcp_dstopts != NULL) {
2286 mi_free(tcp->tcp_dstopts);
2287 tcp->tcp_dstopts = NULL;
2288 tcp->tcp_dstoptslen = 0;
2289 }
2290 ASSERT(tcp->tcp_dstoptslen == 0);
2291 if (tcp->tcp_rthdrdstopts != NULL) {
2292 mi_free(tcp->tcp_rthdrdstopts);
2293 tcp->tcp_rthdrdstopts = NULL;
2294 tcp->tcp_rthdrdstoptslen = 0;
2295 }
2296 ASSERT(tcp->tcp_rthdrdstoptslen == 0);
2297 if (tcp->tcp_rthdr != NULL) {
2298 mi_free(tcp->tcp_rthdr);
2299 tcp->tcp_rthdr = NULL;
2300 tcp->tcp_rthdrlen = 0;
2301 }
2302 ASSERT(tcp->tcp_rthdrlen == 0);
2303
2304 /* Reset fusion-related fields */
2305 tcp->tcp_fused = B_FALSE;
2306 tcp->tcp_unfusable = B_FALSE;
2307 tcp->tcp_fused_sigurg = B_FALSE;
2308 tcp->tcp_loopback_peer = NULL;
2309
2310 tcp->tcp_lso = B_FALSE;
2311
2312 tcp->tcp_in_ack_unsent = 0;
2313 tcp->tcp_cork = B_FALSE;
2314 tcp->tcp_tconnind_started = B_FALSE;
2315
2316 PRESERVE(tcp->tcp_squeue_bytes);
2317
2318 tcp->tcp_closemp_used = B_FALSE;
2319
2320 PRESERVE(tcp->tcp_rsrv_mp);
2321 PRESERVE(tcp->tcp_rsrv_mp_lock);
2322
2323 #ifdef DEBUG
2324 DONTCARE(tcp->tcmp_stk[0]);
2325 #endif
2326
2327 PRESERVE(tcp->tcp_connid);
2328
2329 ASSERT(tcp->tcp_listen_cnt == NULL);
2330 ASSERT(tcp->tcp_reass_tid == 0);
2331
2332 /* Allow the CC algorithm to clean up after itself. */
2333 if (tcp->tcp_cc_algo->cb_destroy != NULL)
2334 tcp->tcp_cc_algo->cb_destroy(&tcp->tcp_ccv);
2335 tcp->tcp_cc_algo = NULL;
2336
2337 #undef DONTCARE
2338 #undef PRESERVE
2339 }
2340
2341 /*
2342 * Initialize the various fields in tcp_t. If parent (the listener) is non
2343 * NULL, certain values will be inheritted from it.
2344 */
2345 void
2346 tcp_init_values(tcp_t *tcp, tcp_t *parent)
2347 {
2348 tcp_stack_t *tcps = tcp->tcp_tcps;
2349 conn_t *connp = tcp->tcp_connp;
2350
2351 ASSERT((connp->conn_family == AF_INET &&
2352 connp->conn_ipversion == IPV4_VERSION) ||
2353 (connp->conn_family == AF_INET6 &&
2354 (connp->conn_ipversion == IPV4_VERSION ||
2355 connp->conn_ipversion == IPV6_VERSION)));
2356
2357 tcp->tcp_ccv.type = IPPROTO_TCP;
2358 tcp->tcp_ccv.ccvc.tcp = tcp;
2359
2360 if (parent == NULL) {
2361 tcp->tcp_cc_algo = tcps->tcps_default_cc_algo;
2362
2363 tcp->tcp_naglim = tcps->tcps_naglim_def;
2364
2365 tcp->tcp_rto_initial = tcps->tcps_rexmit_interval_initial;
2366 tcp->tcp_rto_min = tcps->tcps_rexmit_interval_min;
2367 tcp->tcp_rto_max = tcps->tcps_rexmit_interval_max;
2368
2369 tcp->tcp_first_ctimer_threshold =
2370 tcps->tcps_ip_notify_cinterval;
2371 tcp->tcp_second_ctimer_threshold =
2372 tcps->tcps_ip_abort_cinterval;
2373 tcp->tcp_first_timer_threshold = tcps->tcps_ip_notify_interval;
2374 tcp->tcp_second_timer_threshold = tcps->tcps_ip_abort_interval;
2375
2376 tcp->tcp_fin_wait_2_flush_interval =
2377 tcps->tcps_fin_wait_2_flush_interval;
2378
2379 tcp->tcp_ka_interval = tcps->tcps_keepalive_interval;
2380 tcp->tcp_ka_abort_thres = tcps->tcps_keepalive_abort_interval;
2381 tcp->tcp_ka_cnt = 0;
2382 tcp->tcp_ka_rinterval = 0;
2383
2384 /*
2385 * Default value of tcp_init_cwnd is 0, so no need to set here
2386 * if parent is NULL. But we need to inherit it from parent.
2387 */
2388 } else {
2389 /* Inherit various TCP parameters from the parent. */
2390 tcp->tcp_cc_algo = parent->tcp_cc_algo;
2391
2392 tcp->tcp_naglim = parent->tcp_naglim;
2393
2394 tcp->tcp_rto_initial = parent->tcp_rto_initial;
2395 tcp->tcp_rto_min = parent->tcp_rto_min;
2396 tcp->tcp_rto_max = parent->tcp_rto_max;
2397
2398 tcp->tcp_first_ctimer_threshold =
2399 parent->tcp_first_ctimer_threshold;
2400 tcp->tcp_second_ctimer_threshold =
2401 parent->tcp_second_ctimer_threshold;
2402 tcp->tcp_first_timer_threshold =
2403 parent->tcp_first_timer_threshold;
2404 tcp->tcp_second_timer_threshold =
2405 parent->tcp_second_timer_threshold;
2406
2407 tcp->tcp_fin_wait_2_flush_interval =
2408 parent->tcp_fin_wait_2_flush_interval;
2409
2410 tcp->tcp_ka_interval = parent->tcp_ka_interval;
2411 tcp->tcp_ka_abort_thres = parent->tcp_ka_abort_thres;
2412 tcp->tcp_ka_cnt = parent->tcp_ka_cnt;
2413 tcp->tcp_ka_rinterval = parent->tcp_ka_rinterval;
2414
2415 tcp->tcp_init_cwnd = parent->tcp_init_cwnd;
2416 }
2417
2418 if (tcp->tcp_cc_algo->cb_init != NULL)
2419 VERIFY(tcp->tcp_cc_algo->cb_init(&tcp->tcp_ccv) == 0);
2420
2421 /*
2422 * Initialize tcp_rtt_sa and tcp_rtt_sd so that the calculated RTO
2423 * will be close to tcp_rexmit_interval_initial. By doing this, we
2424 * allow the algorithm to adjust slowly to large fluctuations of RTT
2425 * during first few transmissions of a connection as seen in slow
2426 * links.
2427 */
2428 tcp->tcp_rtt_sa = MSEC2NSEC(tcp->tcp_rto_initial) << 2;
2429 tcp->tcp_rtt_sd = MSEC2NSEC(tcp->tcp_rto_initial) >> 1;
2430 tcp->tcp_rto = tcp_calculate_rto(tcp, tcps,
2431 tcps->tcps_conn_grace_period);
2432
2433 tcp->tcp_timer_backoff = 0;
2434 tcp->tcp_ms_we_have_waited = 0;
2435 tcp->tcp_last_recv_time = ddi_get_lbolt();
2436 tcp->tcp_cwnd_max = tcps->tcps_cwnd_max_;
2437 tcp->tcp_cwnd_ssthresh = TCP_MAX_LARGEWIN;
2438
2439 tcp->tcp_maxpsz_multiplier = tcps->tcps_maxpsz_multiplier;
2440
2441 /* NOTE: ISS is now set in tcp_set_destination(). */
2442
2443 /* Reset fusion-related fields */
2444 tcp->tcp_fused = B_FALSE;
2445 tcp->tcp_unfusable = B_FALSE;
2446 tcp->tcp_fused_sigurg = B_FALSE;
2447 tcp->tcp_loopback_peer = NULL;
2448
2449 /* We rebuild the header template on the next connect/conn_request */
2450
2451 connp->conn_mlp_type = mlptSingle;
2452
2453 /*
2454 * Init the window scale to the max so tcp_rwnd_set() won't pare
2455 * down tcp_rwnd. tcp_set_destination() will set the right value later.
2456 */
2457 tcp->tcp_rcv_ws = TCP_MAX_WINSHIFT;
2458 tcp->tcp_rwnd = connp->conn_rcvbuf;
2459
2460 tcp->tcp_cork = B_FALSE;
2461 /*
2462 * Init the tcp_debug option if it wasn't already set. This value
2463 * determines whether TCP
2464 * calls strlog() to print out debug messages. Doing this
2465 * initialization here means that this value is not inherited thru
2466 * tcp_reinit().
2467 */
2468 if (!connp->conn_debug)
2469 connp->conn_debug = tcps->tcps_dbg;
2470 }
2471
2472 /*
2473 * Update the TCP connection according to change of PMTU.
2474 *
2475 * Path MTU might have changed by either increase or decrease, so need to
2476 * adjust the MSS based on the value of ixa_pmtu. No need to handle tiny
2477 * or negative MSS, since tcp_mss_set() will do it.
2478 */
2479 void
2480 tcp_update_pmtu(tcp_t *tcp, boolean_t decrease_only)
2481 {
2482 uint32_t pmtu;
2483 int32_t mss;
2484 conn_t *connp = tcp->tcp_connp;
2485 ip_xmit_attr_t *ixa = connp->conn_ixa;
2486 iaflags_t ixaflags;
2487
2488 if (tcp->tcp_tcps->tcps_ignore_path_mtu)
2489 return;
2490
2491 if (tcp->tcp_state < TCPS_ESTABLISHED)
2492 return;
2493
2494 /*
2495 * Always call ip_get_pmtu() to make sure that IP has updated
2496 * ixa_flags properly.
2497 */
2498 pmtu = ip_get_pmtu(ixa);
2499 ixaflags = ixa->ixa_flags;
2500
2501 /*
2502 * Calculate the MSS by decreasing the PMTU by conn_ht_iphc_len and
2503 * IPsec overhead if applied. Make sure to use the most recent
2504 * IPsec information.
2505 */
2506 mss = pmtu - connp->conn_ht_iphc_len - conn_ipsec_length(connp);
2507
2508 /*
2509 * Nothing to change, so just return.
2510 */
2511 if (mss == tcp->tcp_mss)
2512 return;
2513
2514 /*
2515 * Currently, for ICMP errors, only PMTU decrease is handled.
2516 */
2517 if (mss > tcp->tcp_mss && decrease_only)
2518 return;
2519
2520 DTRACE_PROBE2(tcp_update_pmtu, int32_t, tcp->tcp_mss, uint32_t, mss);
2521
2522 /*
2523 * Update ixa_fragsize and ixa_pmtu.
2524 */
2525 ixa->ixa_fragsize = ixa->ixa_pmtu = pmtu;
2526
2527 /*
2528 * Adjust MSS and all relevant variables.
2529 */
2530 tcp_mss_set(tcp, mss);
2531
2532 /*
2533 * If the PMTU is below the min size maintained by IP, then ip_get_pmtu
2534 * has set IXAF_PMTU_TOO_SMALL and cleared IXAF_PMTU_IPV4_DF. Since TCP
2535 * has a (potentially different) min size we do the same. Make sure to
2536 * clear IXAF_DONTFRAG, which is used by IP to decide whether to
2537 * fragment the packet.
2538 *
2539 * LSO over IPv6 can not be fragmented. So need to disable LSO
2540 * when IPv6 fragmentation is needed.
2541 */
2542 if (mss < tcp->tcp_tcps->tcps_mss_min)
2543 ixaflags |= IXAF_PMTU_TOO_SMALL;
2544
2545 if (ixaflags & IXAF_PMTU_TOO_SMALL)
2546 ixaflags &= ~(IXAF_DONTFRAG | IXAF_PMTU_IPV4_DF);
2547
2548 if ((connp->conn_ipversion == IPV4_VERSION) &&
2549 !(ixaflags & IXAF_PMTU_IPV4_DF)) {
2550 tcp->tcp_ipha->ipha_fragment_offset_and_flags = 0;
2551 }
2552 ixa->ixa_flags = ixaflags;
2553 }
2554
2555 int
2556 tcp_maxpsz_set(tcp_t *tcp, boolean_t set_maxblk)
2557 {
2558 conn_t *connp = tcp->tcp_connp;
2559 queue_t *q = connp->conn_rq;
2560 int32_t mss = tcp->tcp_mss;
2561 int maxpsz;
2562
2563 if (TCP_IS_DETACHED(tcp))
2564 return (mss);
2565 if (tcp->tcp_fused) {
2566 maxpsz = tcp_fuse_maxpsz(tcp);
2567 mss = INFPSZ;
2568 } else if (tcp->tcp_maxpsz_multiplier == 0) {
2569 /*
2570 * Set the sd_qn_maxpsz according to the socket send buffer
2571 * size, and sd_maxblk to INFPSZ (-1). This will essentially
2572 * instruct the stream head to copyin user data into contiguous
2573 * kernel-allocated buffers without breaking it up into smaller
2574 * chunks. We round up the buffer size to the nearest SMSS.
2575 */
2576 maxpsz = MSS_ROUNDUP(connp->conn_sndbuf, mss);
2577 mss = INFPSZ;
2578 } else {
2579 /*
2580 * Set sd_qn_maxpsz to approx half the (receivers) buffer
2581 * (and a multiple of the mss). This instructs the stream
2582 * head to break down larger than SMSS writes into SMSS-
2583 * size mblks, up to tcp_maxpsz_multiplier mblks at a time.
2584 */
2585 maxpsz = tcp->tcp_maxpsz_multiplier * mss;
2586 if (maxpsz > connp->conn_sndbuf / 2) {
2587 maxpsz = connp->conn_sndbuf / 2;
2588 /* Round up to nearest mss */
2589 maxpsz = MSS_ROUNDUP(maxpsz, mss);
2590 }
2591 }
2592
2593 (void) proto_set_maxpsz(q, connp, maxpsz);
2594 if (!(IPCL_IS_NONSTR(connp)))
2595 connp->conn_wq->q_maxpsz = maxpsz;
2596 if (set_maxblk)
2597 (void) proto_set_tx_maxblk(q, connp, mss);
2598 return (mss);
2599 }
2600
2601 /* For /dev/tcp aka AF_INET open */
2602 static int
2603 tcp_openv4(queue_t *q, dev_t *devp, int flag, int sflag, cred_t *credp)
2604 {
2605 return (tcp_open(q, devp, flag, sflag, credp, B_FALSE));
2606 }
2607
2608 /* For /dev/tcp6 aka AF_INET6 open */
2609 static int
2610 tcp_openv6(queue_t *q, dev_t *devp, int flag, int sflag, cred_t *credp)
2611 {
2612 return (tcp_open(q, devp, flag, sflag, credp, B_TRUE));
2613 }
2614
2615 conn_t *
2616 tcp_create_common(cred_t *credp, boolean_t isv6, boolean_t issocket,
2617 int *errorp)
2618 {
2619 tcp_t *tcp = NULL;
2620 conn_t *connp;
2621 zoneid_t zoneid;
2622 tcp_stack_t *tcps;
2623 squeue_t *sqp;
2624
2625 ASSERT(errorp != NULL);
2626 /*
2627 * Find the proper zoneid and netstack.
2628 */
2629 /*
2630 * Special case for install: miniroot needs to be able to
2631 * access files via NFS as though it were always in the
2632 * global zone.
2633 */
2634 if (credp == kcred && nfs_global_client_only != 0) {
2635 zoneid = GLOBAL_ZONEID;
2636 tcps = netstack_find_by_stackid(GLOBAL_NETSTACKID)->
2637 netstack_tcp;
2638 ASSERT(tcps != NULL);
2639 } else {
2640 netstack_t *ns;
2641 int err;
2642
2643 if ((err = secpolicy_basic_net_access(credp)) != 0) {
2644 *errorp = err;
2645 return (NULL);
2646 }
2647
2648 ns = netstack_find_by_cred(credp);
2649 ASSERT(ns != NULL);
2650 tcps = ns->netstack_tcp;
2651 ASSERT(tcps != NULL);
2652
2653 /*
2654 * For exclusive stacks we set the zoneid to zero
2655 * to make TCP operate as if in the global zone.
2656 */
2657 if (tcps->tcps_netstack->netstack_stackid !=
2658 GLOBAL_NETSTACKID)
2659 zoneid = GLOBAL_ZONEID;
2660 else
2661 zoneid = crgetzoneid(credp);
2662 }
2663
2664 sqp = IP_SQUEUE_GET((uint_t)gethrtime());
2665 connp = tcp_get_conn(sqp, tcps);
2666 /*
2667 * Both tcp_get_conn and netstack_find_by_cred incremented refcnt,
2668 * so we drop it by one.
2669 */
2670 netstack_rele(tcps->tcps_netstack);
2671 if (connp == NULL) {
2672 *errorp = ENOSR;
2673 return (NULL);
2674 }
2675 ASSERT(connp->conn_ixa->ixa_protocol == connp->conn_proto);
2676
2677 connp->conn_sqp = sqp;
2678 connp->conn_initial_sqp = connp->conn_sqp;
2679 connp->conn_ixa->ixa_sqp = connp->conn_sqp;
2680 tcp = connp->conn_tcp;
2681
2682 /*
2683 * Besides asking IP to set the checksum for us, have conn_ip_output
2684 * to do the following checks when necessary:
2685 *
2686 * IXAF_VERIFY_SOURCE: drop packets when our outer source goes invalid
2687 * IXAF_VERIFY_PMTU: verify PMTU changes
2688 * IXAF_VERIFY_LSO: verify LSO capability changes
2689 */
2690 connp->conn_ixa->ixa_flags |= IXAF_SET_ULP_CKSUM | IXAF_VERIFY_SOURCE |
2691 IXAF_VERIFY_PMTU | IXAF_VERIFY_LSO;
2692
2693 if (!tcps->tcps_dev_flow_ctl)
2694 connp->conn_ixa->ixa_flags |= IXAF_NO_DEV_FLOW_CTL;
2695
2696 if (isv6) {
2697 connp->conn_ixa->ixa_src_preferences = IPV6_PREFER_SRC_DEFAULT;
2698 connp->conn_ipversion = IPV6_VERSION;
2699 connp->conn_family = AF_INET6;
2700 tcp->tcp_mss = tcps->tcps_mss_def_ipv6;
2701 connp->conn_default_ttl = tcps->tcps_ipv6_hoplimit;
2702 } else {
2703 connp->conn_ipversion = IPV4_VERSION;
2704 connp->conn_family = AF_INET;
2705 tcp->tcp_mss = tcps->tcps_mss_def_ipv4;
2706 connp->conn_default_ttl = tcps->tcps_ipv4_ttl;
2707 }
2708 connp->conn_xmit_ipp.ipp_unicast_hops = connp->conn_default_ttl;
2709
2710 crhold(credp);
2711 connp->conn_cred = credp;
2712 connp->conn_cpid = curproc->p_pid;
2713 connp->conn_open_time = ddi_get_lbolt64();
2714
2715 /* Cache things in the ixa without any refhold */
2716 ASSERT(!(connp->conn_ixa->ixa_free_flags & IXA_FREE_CRED));
2717 connp->conn_ixa->ixa_cred = credp;
2718 connp->conn_ixa->ixa_cpid = connp->conn_cpid;
2719
2720 connp->conn_zoneid = zoneid;
2721 /* conn_allzones can not be set this early, hence no IPCL_ZONEID */
2722 connp->conn_ixa->ixa_zoneid = zoneid;
2723 connp->conn_mlp_type = mlptSingle;
2724 ASSERT(connp->conn_netstack == tcps->tcps_netstack);
2725 ASSERT(tcp->tcp_tcps == tcps);
2726
2727 /*
2728 * If the caller has the process-wide flag set, then default to MAC
2729 * exempt mode. This allows read-down to unlabeled hosts.
2730 */
2731 if (getpflags(NET_MAC_AWARE, credp) != 0)
2732 connp->conn_mac_mode = CONN_MAC_AWARE;
2733
2734 connp->conn_zone_is_global = (crgetzoneid(credp) == GLOBAL_ZONEID);
2735
2736 if (issocket) {
2737 tcp->tcp_issocket = 1;
2738 }
2739
2740 connp->conn_rcvbuf = tcps->tcps_recv_hiwat;
2741 connp->conn_sndbuf = tcps->tcps_xmit_hiwat;
2742 if (tcps->tcps_snd_lowat_fraction != 0) {
2743 connp->conn_sndlowat = connp->conn_sndbuf /
2744 tcps->tcps_snd_lowat_fraction;
2745 } else {
2746 connp->conn_sndlowat = tcps->tcps_xmit_lowat;
2747 }
2748 connp->conn_so_type = SOCK_STREAM;
2749 connp->conn_wroff = connp->conn_ht_iphc_allocated +
2750 tcps->tcps_wroff_xtra;
2751
2752 SOCK_CONNID_INIT(tcp->tcp_connid);
2753 /* DTrace ignores this - it isn't a tcp:::state-change */
2754 tcp->tcp_state = TCPS_IDLE;
2755 tcp_init_values(tcp, NULL);
2756 return (connp);
2757 }
2758
2759 static int
2760 tcp_open(queue_t *q, dev_t *devp, int flag, int sflag, cred_t *credp,
2761 boolean_t isv6)
2762 {
2763 tcp_t *tcp = NULL;
2764 conn_t *connp = NULL;
2765 int err;
2766 vmem_t *minor_arena = NULL;
2767 dev_t conn_dev;
2768 boolean_t issocket;
2769
2770 if (q->q_ptr != NULL)
2771 return (0);
2772
2773 if (sflag == MODOPEN)
2774 return (EINVAL);
2775
2776 if ((ip_minor_arena_la != NULL) && (flag & SO_SOCKSTR) &&
2777 ((conn_dev = inet_minor_alloc(ip_minor_arena_la)) != 0)) {
2778 minor_arena = ip_minor_arena_la;
2779 } else {
2780 /*
2781 * Either minor numbers in the large arena were exhausted
2782 * or a non socket application is doing the open.
2783 * Try to allocate from the small arena.
2784 */
2785 if ((conn_dev = inet_minor_alloc(ip_minor_arena_sa)) == 0) {
2786 return (EBUSY);
2787 }
2788 minor_arena = ip_minor_arena_sa;
2789 }
2790
2791 ASSERT(minor_arena != NULL);
2792
2793 *devp = makedevice(getmajor(*devp), (minor_t)conn_dev);
2794
2795 if (flag & SO_FALLBACK) {
2796 /*
2797 * Non streams socket needs a stream to fallback to
2798 */
2799 RD(q)->q_ptr = (void *)conn_dev;
2800 WR(q)->q_qinfo = &tcp_fallback_sock_winit;
2801 WR(q)->q_ptr = (void *)minor_arena;
2802 qprocson(q);
2803 return (0);
2804 } else if (flag & SO_ACCEPTOR) {
2805 q->q_qinfo = &tcp_acceptor_rinit;
2806 /*
2807 * the conn_dev and minor_arena will be subsequently used by
2808 * tcp_tli_accept() and tcp_tpi_close_accept() to figure out
2809 * the minor device number for this connection from the q_ptr.
2810 */
2811 RD(q)->q_ptr = (void *)conn_dev;
2812 WR(q)->q_qinfo = &tcp_acceptor_winit;
2813 WR(q)->q_ptr = (void *)minor_arena;
2814 qprocson(q);
2815 return (0);
2816 }
2817
2818 issocket = flag & SO_SOCKSTR;
2819 connp = tcp_create_common(credp, isv6, issocket, &err);
2820
2821 if (connp == NULL) {
2822 inet_minor_free(minor_arena, conn_dev);
2823 q->q_ptr = WR(q)->q_ptr = NULL;
2824 return (err);
2825 }
2826
2827 connp->conn_rq = q;
2828 connp->conn_wq = WR(q);
2829 q->q_ptr = WR(q)->q_ptr = connp;
2830
2831 connp->conn_dev = conn_dev;
2832 connp->conn_minor_arena = minor_arena;
2833
2834 ASSERT(q->q_qinfo == &tcp_rinitv4 || q->q_qinfo == &tcp_rinitv6);
2835 ASSERT(WR(q)->q_qinfo == &tcp_winit);
2836
2837 tcp = connp->conn_tcp;
2838
2839 if (issocket) {
2840 WR(q)->q_qinfo = &tcp_sock_winit;
2841 } else {
2842 #ifdef _ILP32
2843 tcp->tcp_acceptor_id = (t_uscalar_t)RD(q);
2844 #else
2845 tcp->tcp_acceptor_id = conn_dev;
2846 #endif /* _ILP32 */
2847 tcp_acceptor_hash_insert(tcp->tcp_acceptor_id, tcp);
2848 }
2849
2850 /*
2851 * Put the ref for TCP. Ref for IP was already put
2852 * by ipcl_conn_create. Also Make the conn_t globally
2853 * visible to walkers
2854 */
2855 mutex_enter(&connp->conn_lock);
2856 CONN_INC_REF_LOCKED(connp);
2857 ASSERT(connp->conn_ref == 2);
2858 connp->conn_state_flags &= ~CONN_INCIPIENT;
2859 mutex_exit(&connp->conn_lock);
2860
2861 qprocson(q);
2862 return (0);
2863 }
2864
2865 /*
2866 * Build/update the tcp header template (in conn_ht_iphc) based on
2867 * conn_xmit_ipp. The headers include ip6_t, any extension
2868 * headers, and the maximum size tcp header (to avoid reallocation
2869 * on the fly for additional tcp options).
2870 *
2871 * Assumes the caller has already set conn_{faddr,laddr,fport,lport,flowinfo}.
2872 * Returns failure if can't allocate memory.
2873 */
2874 int
2875 tcp_build_hdrs(tcp_t *tcp)
2876 {
2877 tcp_stack_t *tcps = tcp->tcp_tcps;
2878 conn_t *connp = tcp->tcp_connp;
2879 char buf[TCP_MAX_HDR_LENGTH];
2880 uint_t buflen;
2881 uint_t ulplen = TCP_MIN_HEADER_LENGTH;
2882 uint_t extralen = TCP_MAX_TCP_OPTIONS_LENGTH;
2883 tcpha_t *tcpha;
2884 uint32_t cksum;
2885 int error;
2886
2887 /*
2888 * We might be called after the connection is set up, and we might
2889 * have TS options already in the TCP header. Thus we save any
2890 * existing tcp header.
2891 */
2892 buflen = connp->conn_ht_ulp_len;
2893 if (buflen != 0) {
2894 bcopy(connp->conn_ht_ulp, buf, buflen);
2895 extralen -= buflen - ulplen;
2896 ulplen = buflen;
2897 }
2898
2899 /* Grab lock to satisfy ASSERT; TCP is serialized using squeue */
2900 mutex_enter(&connp->conn_lock);
2901 error = conn_build_hdr_template(connp, ulplen, extralen,
2902 &connp->conn_laddr_v6, &connp->conn_faddr_v6, connp->conn_flowinfo);
2903 mutex_exit(&connp->conn_lock);
2904 if (error != 0)
2905 return (error);
2906
2907 /*
2908 * Any routing header/option has been massaged. The checksum difference
2909 * is stored in conn_sum for later use.
2910 */
2911 tcpha = (tcpha_t *)connp->conn_ht_ulp;
2912 tcp->tcp_tcpha = tcpha;
2913
2914 /* restore any old tcp header */
2915 if (buflen != 0) {
2916 bcopy(buf, connp->conn_ht_ulp, buflen);
2917 } else {
2918 tcpha->tha_sum = 0;
2919 tcpha->tha_urp = 0;
2920 tcpha->tha_ack = 0;
2921 tcpha->tha_offset_and_reserved = (5 << 4);
2922 tcpha->tha_lport = connp->conn_lport;
2923 tcpha->tha_fport = connp->conn_fport;
2924 }
2925
2926 /*
2927 * IP wants our header length in the checksum field to
2928 * allow it to perform a single pseudo-header+checksum
2929 * calculation on behalf of TCP.
2930 * Include the adjustment for a source route once IP_OPTIONS is set.
2931 */
2932 cksum = sizeof (tcpha_t) + connp->conn_sum;
2933 cksum = (cksum >> 16) + (cksum & 0xFFFF);
2934 ASSERT(cksum < 0x10000);
2935 tcpha->tha_sum = htons(cksum);
2936
2937 if (connp->conn_ipversion == IPV4_VERSION)
2938 tcp->tcp_ipha = (ipha_t *)connp->conn_ht_iphc;
2939 else
2940 tcp->tcp_ip6h = (ip6_t *)connp->conn_ht_iphc;
2941
2942 if (connp->conn_ht_iphc_allocated + tcps->tcps_wroff_xtra >
2943 connp->conn_wroff) {
2944 connp->conn_wroff = connp->conn_ht_iphc_allocated +
2945 tcps->tcps_wroff_xtra;
2946 (void) proto_set_tx_wroff(connp->conn_rq, connp,
2947 connp->conn_wroff);
2948 }
2949 return (0);
2950 }
2951
2952 /*
2953 * tcp_rwnd_set() is called to adjust the receive window to a desired value.
2954 * We do not allow the receive window to shrink. After setting rwnd,
2955 * set the flow control hiwat of the stream.
2956 *
2957 * This function is called in 2 cases:
2958 *
2959 * 1) Before data transfer begins, in tcp_input_listener() for accepting a
2960 * connection (passive open) and in tcp_input_data() for active connect.
2961 * This is called after tcp_mss_set() when the desired MSS value is known.
2962 * This makes sure that our window size is a mutiple of the other side's
2963 * MSS.
2964 * 2) Handling SO_RCVBUF option.
2965 *
2966 * It is ASSUMED that the requested size is a multiple of the current MSS.
2967 *
2968 * XXX - Should allow a lower rwnd than tcp_recv_hiwat_minmss * mss if the
2969 * user requests so.
2970 */
2971 int
2972 tcp_rwnd_set(tcp_t *tcp, uint32_t rwnd)
2973 {
2974 uint32_t mss = tcp->tcp_mss;
2975 uint32_t old_max_rwnd;
2976 uint32_t max_transmittable_rwnd;
2977 boolean_t tcp_detached = TCP_IS_DETACHED(tcp);
2978 tcp_stack_t *tcps = tcp->tcp_tcps;
2979 conn_t *connp = tcp->tcp_connp;
2980
2981 /*
2982 * Insist on a receive window that is at least
2983 * tcp_recv_hiwat_minmss * MSS (default 4 * MSS) to avoid
2984 * funny TCP interactions of Nagle algorithm, SWS avoidance
2985 * and delayed acknowledgement.
2986 */
2987 rwnd = MAX(rwnd, tcps->tcps_recv_hiwat_minmss * mss);
2988
2989 if (tcp->tcp_fused) {
2990 size_t sth_hiwat;
2991 tcp_t *peer_tcp = tcp->tcp_loopback_peer;
2992
2993 ASSERT(peer_tcp != NULL);
2994 sth_hiwat = tcp_fuse_set_rcv_hiwat(tcp, rwnd);
2995 if (!tcp_detached) {
2996 (void) proto_set_rx_hiwat(connp->conn_rq, connp,
2997 sth_hiwat);
2998 tcp_set_recv_threshold(tcp, sth_hiwat >> 3);
2999 }
3000
3001 /* Caller could have changed tcp_rwnd; update tha_win */
3002 if (tcp->tcp_tcpha != NULL) {
3003 tcp->tcp_tcpha->tha_win =
3004 htons(tcp->tcp_rwnd >> tcp->tcp_rcv_ws);
3005 }
3006 if ((tcp->tcp_rcv_ws > 0) && rwnd > tcp->tcp_cwnd_max)
3007 tcp->tcp_cwnd_max = rwnd;
3008
3009 /*
3010 * In the fusion case, the maxpsz stream head value of
3011 * our peer is set according to its send buffer size
3012 * and our receive buffer size; since the latter may
3013 * have changed we need to update the peer's maxpsz.
3014 */
3015 (void) tcp_maxpsz_set(peer_tcp, B_TRUE);
3016 return (sth_hiwat);
3017 }
3018
3019 if (tcp_detached)
3020 old_max_rwnd = tcp->tcp_rwnd;
3021 else
3022 old_max_rwnd = connp->conn_rcvbuf;
3023
3024
3025 /*
3026 * If window size info has already been exchanged, TCP should not
3027 * shrink the window. Shrinking window is doable if done carefully.
3028 * We may add that support later. But so far there is not a real
3029 * need to do that.
3030 */
3031 if (rwnd < old_max_rwnd && tcp->tcp_state > TCPS_SYN_SENT) {
3032 /* MSS may have changed, do a round up again. */
3033 rwnd = MSS_ROUNDUP(old_max_rwnd, mss);
3034 }
3035
3036 /*
3037 * tcp_rcv_ws starts with TCP_MAX_WINSHIFT so the following check
3038 * can be applied even before the window scale option is decided.
3039 */
3040 max_transmittable_rwnd = TCP_MAXWIN << tcp->tcp_rcv_ws;
3041 if (rwnd > max_transmittable_rwnd) {
3042 rwnd = max_transmittable_rwnd -
3043 (max_transmittable_rwnd % mss);
3044 if (rwnd < mss)
3045 rwnd = max_transmittable_rwnd;
3046 /*
3047 * If we're over the limit we may have to back down tcp_rwnd.
3048 * The increment below won't work for us. So we set all three
3049 * here and the increment below will have no effect.
3050 */
3051 tcp->tcp_rwnd = old_max_rwnd = rwnd;
3052 }
3053 if (tcp->tcp_localnet) {
3054 tcp->tcp_rack_abs_max =
3055 MIN(tcps->tcps_local_dacks_max, rwnd / mss / 2);
3056 } else {
3057 /*
3058 * For a remote host on a different subnet (through a router),
3059 * we ack every other packet to be conforming to RFC1122.
3060 * tcp_deferred_acks_max is default to 2.
3061 */
3062 tcp->tcp_rack_abs_max =
3063 MIN(tcps->tcps_deferred_acks_max, rwnd / mss / 2);
3064 }
3065 if (tcp->tcp_rack_cur_max > tcp->tcp_rack_abs_max)
3066 tcp->tcp_rack_cur_max = tcp->tcp_rack_abs_max;
3067 else
3068 tcp->tcp_rack_cur_max = 0;
3069 /*
3070 * Increment the current rwnd by the amount the maximum grew (we
3071 * can not overwrite it since we might be in the middle of a
3072 * connection.)
3073 */
3074 tcp->tcp_rwnd += rwnd - old_max_rwnd;
3075 connp->conn_rcvbuf = rwnd;
3076
3077 /* Are we already connected? */
3078 if (tcp->tcp_tcpha != NULL) {
3079 tcp->tcp_tcpha->tha_win =
3080 htons(tcp->tcp_rwnd >> tcp->tcp_rcv_ws);
3081 }
3082
3083 if ((tcp->tcp_rcv_ws > 0) && rwnd > tcp->tcp_cwnd_max)
3084 tcp->tcp_cwnd_max = rwnd;
3085
3086 if (tcp_detached)
3087 return (rwnd);
3088
3089 tcp_set_recv_threshold(tcp, rwnd >> 3);
3090
3091 (void) proto_set_rx_hiwat(connp->conn_rq, connp, rwnd);
3092 return (rwnd);
3093 }
3094
3095 int
3096 tcp_do_unbind(conn_t *connp)
3097 {
3098 tcp_t *tcp = connp->conn_tcp;
3099 int32_t oldstate;
3100
3101 switch (tcp->tcp_state) {
3102 case TCPS_BOUND:
3103 case TCPS_LISTEN:
3104 break;
3105 default:
3106 return (-TOUTSTATE);
3107 }
3108
3109 /*
3110 * Need to clean up all the eagers since after the unbind, segments
3111 * will no longer be delivered to this listener stream.
3112 */
3113 mutex_enter(&tcp->tcp_eager_lock);
3114 if (tcp->tcp_conn_req_cnt_q0 != 0 || tcp->tcp_conn_req_cnt_q != 0) {
3115 tcp_eager_cleanup(tcp, 0);
3116 }
3117 mutex_exit(&tcp->tcp_eager_lock);
3118
3119 /* Clean up the listener connection counter if necessary. */
3120 if (tcp->tcp_listen_cnt != NULL)
3121 TCP_DECR_LISTEN_CNT(tcp);
3122 connp->conn_laddr_v6 = ipv6_all_zeros;
3123 connp->conn_saddr_v6 = ipv6_all_zeros;
3124 tcp_bind_hash_remove(tcp);
3125 oldstate = tcp->tcp_state;
3126 tcp->tcp_state = TCPS_IDLE;
3127 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
3128 connp->conn_ixa, void, NULL, tcp_t *, tcp, void, NULL,
3129 int32_t, oldstate);
3130
3131 ip_unbind(connp);
3132 bzero(&connp->conn_ports, sizeof (connp->conn_ports));
3133
3134 return (0);
3135 }
3136
3137 /*
3138 * Collect protocol properties to send to the upper handle.
3139 */
3140 void
3141 tcp_get_proto_props(tcp_t *tcp, struct sock_proto_props *sopp)
3142 {
3143 conn_t *connp = tcp->tcp_connp;
3144
3145 sopp->sopp_flags = SOCKOPT_RCVHIWAT | SOCKOPT_MAXBLK | SOCKOPT_WROFF;
3146 sopp->sopp_maxblk = tcp_maxpsz_set(tcp, B_FALSE);
3147
3148 sopp->sopp_rxhiwat = tcp->tcp_fused ?
3149 tcp_fuse_set_rcv_hiwat(tcp, connp->conn_rcvbuf) :
3150 connp->conn_rcvbuf;
3151 /*
3152 * Determine what write offset value to use depending on SACK and
3153 * whether the endpoint is fused or not.
3154 */
3155 if (tcp->tcp_fused) {
3156 ASSERT(tcp->tcp_loopback);
3157 ASSERT(tcp->tcp_loopback_peer != NULL);
3158 /*
3159 * For fused tcp loopback, set the stream head's write
3160 * offset value to zero since we won't be needing any room
3161 * for TCP/IP headers. This would also improve performance
3162 * since it would reduce the amount of work done by kmem.
3163 * Non-fused tcp loopback case is handled separately below.
3164 */
3165 sopp->sopp_wroff = 0;
3166 /*
3167 * Update the peer's transmit parameters according to
3168 * our recently calculated high water mark value.
3169 */
3170 (void) tcp_maxpsz_set(tcp->tcp_loopback_peer, B_TRUE);
3171 } else if (tcp->tcp_snd_sack_ok) {
3172 sopp->sopp_wroff = connp->conn_ht_iphc_allocated +
3173 (tcp->tcp_loopback ? 0 : tcp->tcp_tcps->tcps_wroff_xtra);
3174 } else {
3175 sopp->sopp_wroff = connp->conn_ht_iphc_len +
3176 (tcp->tcp_loopback ? 0 : tcp->tcp_tcps->tcps_wroff_xtra);
3177 }
3178
3179 if (tcp->tcp_loopback) {
3180 sopp->sopp_flags |= SOCKOPT_LOOPBACK;
3181 sopp->sopp_loopback = B_TRUE;
3182 }
3183 }
3184
3185 /*
3186 * Check the usability of ZEROCOPY. It's instead checking the flag set by IP.
3187 */
3188 boolean_t
3189 tcp_zcopy_check(tcp_t *tcp)
3190 {
3191 conn_t *connp = tcp->tcp_connp;
3192 ip_xmit_attr_t *ixa = connp->conn_ixa;
3193 boolean_t zc_enabled = B_FALSE;
3194 tcp_stack_t *tcps = tcp->tcp_tcps;
3195
3196 if (do_tcpzcopy == 2)
3197 zc_enabled = B_TRUE;
3198 else if ((do_tcpzcopy == 1) && (ixa->ixa_flags & IXAF_ZCOPY_CAPAB))
3199 zc_enabled = B_TRUE;
3200
3201 tcp->tcp_snd_zcopy_on = zc_enabled;
3202 if (!TCP_IS_DETACHED(tcp)) {
3203 if (zc_enabled) {
3204 ixa->ixa_flags |= IXAF_VERIFY_ZCOPY;
3205 (void) proto_set_tx_copyopt(connp->conn_rq, connp,
3206 ZCVMSAFE);
3207 TCP_STAT(tcps, tcp_zcopy_on);
3208 } else {
3209 ixa->ixa_flags &= ~IXAF_VERIFY_ZCOPY;
3210 (void) proto_set_tx_copyopt(connp->conn_rq, connp,
3211 ZCVMUNSAFE);
3212 TCP_STAT(tcps, tcp_zcopy_off);
3213 }
3214 }
3215 return (zc_enabled);
3216 }
3217
3218 /*
3219 * Backoff from a zero-copy message by copying data to a new allocated
3220 * message and freeing the original desballoca'ed segmapped message.
3221 *
3222 * This function is called by following two callers:
3223 * 1. tcp_timer: fix_xmitlist is set to B_TRUE, because it's safe to free
3224 * the origial desballoca'ed message and notify sockfs. This is in re-
3225 * transmit state.
3226 * 2. tcp_output: fix_xmitlist is set to B_FALSE. Flag STRUIO_ZCNOTIFY need
3227 * to be copied to new message.
3228 */
3229 mblk_t *
3230 tcp_zcopy_backoff(tcp_t *tcp, mblk_t *bp, boolean_t fix_xmitlist)
3231 {
3232 mblk_t *nbp;
3233 mblk_t *head = NULL;
3234 mblk_t *tail = NULL;
3235 tcp_stack_t *tcps = tcp->tcp_tcps;
3236
3237 ASSERT(bp != NULL);
3238 while (bp != NULL) {
3239 if (IS_VMLOANED_MBLK(bp)) {
3240 TCP_STAT(tcps, tcp_zcopy_backoff);
3241 if ((nbp = copyb(bp)) == NULL) {
3242 tcp->tcp_xmit_zc_clean = B_FALSE;
3243 if (tail != NULL)
3244 tail->b_cont = bp;
3245 return ((head == NULL) ? bp : head);
3246 }
3247
3248 if (bp->b_datap->db_struioflag & STRUIO_ZCNOTIFY) {
3249 if (fix_xmitlist)
3250 tcp_zcopy_notify(tcp);
3251 else
3252 nbp->b_datap->db_struioflag |=
3253 STRUIO_ZCNOTIFY;
3254 }
3255 nbp->b_cont = bp->b_cont;
3256
3257 /*
3258 * Copy saved information and adjust tcp_xmit_tail
3259 * if needed.
3260 */
3261 if (fix_xmitlist) {
3262 nbp->b_prev = bp->b_prev;
3263 nbp->b_next = bp->b_next;
3264
3265 if (tcp->tcp_xmit_tail == bp)
3266 tcp->tcp_xmit_tail = nbp;
3267 }
3268
3269 /* Free the original message. */
3270 bp->b_prev = NULL;
3271 bp->b_next = NULL;
3272 freeb(bp);
3273
3274 bp = nbp;
3275 }
3276
3277 if (head == NULL) {
3278 head = bp;
3279 }
3280 if (tail == NULL) {
3281 tail = bp;
3282 } else {
3283 tail->b_cont = bp;
3284 tail = bp;
3285 }
3286
3287 /* Move forward. */
3288 bp = bp->b_cont;
3289 }
3290
3291 if (fix_xmitlist) {
3292 tcp->tcp_xmit_last = tail;
3293 tcp->tcp_xmit_zc_clean = B_TRUE;
3294 }
3295
3296 return (head);
3297 }
3298
3299 void
3300 tcp_zcopy_notify(tcp_t *tcp)
3301 {
3302 struct stdata *stp;
3303 conn_t *connp;
3304
3305 if (tcp->tcp_detached)
3306 return;
3307 connp = tcp->tcp_connp;
3308 if (IPCL_IS_NONSTR(connp)) {
3309 (*connp->conn_upcalls->su_zcopy_notify)
3310 (connp->conn_upper_handle);
3311 return;
3312 }
3313 stp = STREAM(connp->conn_rq);
3314 mutex_enter(&stp->sd_lock);
3315 stp->sd_flag |= STZCNOTIFY;
3316 cv_broadcast(&stp->sd_zcopy_wait);
3317 mutex_exit(&stp->sd_lock);
3318 }
3319
3320 /*
3321 * Update the TCP connection according to change of LSO capability.
3322 */
3323 static void
3324 tcp_update_lso(tcp_t *tcp, ip_xmit_attr_t *ixa)
3325 {
3326 /*
3327 * We check against IPv4 header length to preserve the old behavior
3328 * of only enabling LSO when there are no IP options.
3329 * But this restriction might not be necessary at all. Before removing
3330 * it, need to verify how LSO is handled for source routing case, with
3331 * which IP does software checksum.
3332 *
3333 * For IPv6, whenever any extension header is needed, LSO is supressed.
3334 */
3335 if (ixa->ixa_ip_hdr_length != ((ixa->ixa_flags & IXAF_IS_IPV4) ?
3336 IP_SIMPLE_HDR_LENGTH : IPV6_HDR_LEN))
3337 return;
3338
3339 /*
3340 * Either the LSO capability newly became usable, or it has changed.
3341 */
3342 if (ixa->ixa_flags & IXAF_LSO_CAPAB) {
3343 ill_lso_capab_t *lsoc = &ixa->ixa_lso_capab;
3344 uint_t lso_max = (ixa->ixa_flags & IXAF_IS_IPV4) ?
3345 lsoc->ill_lso_max_tcpv4 : lsoc->ill_lso_max_tcpv6;
3346
3347 ASSERT3U(lso_max, >, 0);
3348 tcp->tcp_lso_max = MIN(TCP_MAX_LSO_LENGTH, lso_max);
3349
3350 DTRACE_PROBE3(tcp_update_lso, boolean_t, tcp->tcp_lso,
3351 boolean_t, B_TRUE, uint32_t, tcp->tcp_lso_max);
3352
3353 /*
3354 * If LSO to be enabled, notify the STREAM header with larger
3355 * data block.
3356 */
3357 if (!tcp->tcp_lso)
3358 tcp->tcp_maxpsz_multiplier = 0;
3359
3360 tcp->tcp_lso = B_TRUE;
3361 TCP_STAT(tcp->tcp_tcps, tcp_lso_enabled);
3362 } else { /* LSO capability is not usable any more. */
3363 DTRACE_PROBE3(tcp_update_lso, boolean_t, tcp->tcp_lso,
3364 boolean_t, B_FALSE, uint32_t, tcp->tcp_lso_max);
3365
3366 /*
3367 * If LSO to be disabled, notify the STREAM header with smaller
3368 * data block. And need to restore fragsize to PMTU.
3369 */
3370 if (tcp->tcp_lso) {
3371 tcp->tcp_maxpsz_multiplier =
3372 tcp->tcp_tcps->tcps_maxpsz_multiplier;
3373 ixa->ixa_fragsize = ixa->ixa_pmtu;
3374 tcp->tcp_lso = B_FALSE;
3375 TCP_STAT(tcp->tcp_tcps, tcp_lso_disabled);
3376 }
3377 }
3378
3379 (void) tcp_maxpsz_set(tcp, B_TRUE);
3380 }
3381
3382 /*
3383 * Update the TCP connection according to change of ZEROCOPY capability.
3384 */
3385 static void
3386 tcp_update_zcopy(tcp_t *tcp)
3387 {
3388 conn_t *connp = tcp->tcp_connp;
3389 tcp_stack_t *tcps = tcp->tcp_tcps;
3390
3391 if (tcp->tcp_snd_zcopy_on) {
3392 tcp->tcp_snd_zcopy_on = B_FALSE;
3393 if (!TCP_IS_DETACHED(tcp)) {
3394 (void) proto_set_tx_copyopt(connp->conn_rq, connp,
3395 ZCVMUNSAFE);
3396 TCP_STAT(tcps, tcp_zcopy_off);
3397 }
3398 } else {
3399 tcp->tcp_snd_zcopy_on = B_TRUE;
3400 if (!TCP_IS_DETACHED(tcp)) {
3401 (void) proto_set_tx_copyopt(connp->conn_rq, connp,
3402 ZCVMSAFE);
3403 TCP_STAT(tcps, tcp_zcopy_on);
3404 }
3405 }
3406 }
3407
3408 /*
3409 * Notify function registered with ip_xmit_attr_t. It's called in the squeue
3410 * so it's safe to update the TCP connection.
3411 */
3412 /* ARGSUSED1 */
3413 static void
3414 tcp_notify(void *arg, ip_xmit_attr_t *ixa, ixa_notify_type_t ntype,
3415 ixa_notify_arg_t narg)
3416 {
3417 tcp_t *tcp = (tcp_t *)arg;
3418 conn_t *connp = tcp->tcp_connp;
3419
3420 switch (ntype) {
3421 case IXAN_LSO:
3422 tcp_update_lso(tcp, connp->conn_ixa);
3423 break;
3424 case IXAN_PMTU:
3425 tcp_update_pmtu(tcp, B_FALSE);
3426 break;
3427 case IXAN_ZCOPY:
3428 tcp_update_zcopy(tcp);
3429 break;
3430 default:
3431 break;
3432 }
3433 }
3434
3435 /*
3436 * The TCP write service routine should never be called...
3437 */
3438 /* ARGSUSED */
3439 static int
3440 tcp_wsrv(queue_t *q)
3441 {
3442 tcp_stack_t *tcps = Q_TO_TCP(q)->tcp_tcps;
3443
3444 TCP_STAT(tcps, tcp_wsrv_called);
3445 return (0);
3446 }
3447
3448 /*
3449 * Hash list lookup routine for tcp_t structures.
3450 * Returns with a CONN_INC_REF tcp structure. Caller must do a CONN_DEC_REF.
3451 */
3452 tcp_t *
3453 tcp_acceptor_hash_lookup(t_uscalar_t id, tcp_stack_t *tcps)
3454 {
3455 tf_t *tf;
3456 tcp_t *tcp;
3457
3458 tf = &tcps->tcps_acceptor_fanout[TCP_ACCEPTOR_HASH(id)];
3459 mutex_enter(&tf->tf_lock);
3460 for (tcp = tf->tf_tcp; tcp != NULL;
3461 tcp = tcp->tcp_acceptor_hash) {
3462 if (tcp->tcp_acceptor_id == id) {
3463 CONN_INC_REF(tcp->tcp_connp);
3464 mutex_exit(&tf->tf_lock);
3465 return (tcp);
3466 }
3467 }
3468 mutex_exit(&tf->tf_lock);
3469 return (NULL);
3470 }
3471
3472 /*
3473 * Hash list insertion routine for tcp_t structures.
3474 */
3475 void
3476 tcp_acceptor_hash_insert(t_uscalar_t id, tcp_t *tcp)
3477 {
3478 tf_t *tf;
3479 tcp_t **tcpp;
3480 tcp_t *tcpnext;
3481 tcp_stack_t *tcps = tcp->tcp_tcps;
3482
3483 tf = &tcps->tcps_acceptor_fanout[TCP_ACCEPTOR_HASH(id)];
3484
3485 if (tcp->tcp_ptpahn != NULL)
3486 tcp_acceptor_hash_remove(tcp);
3487 tcpp = &tf->tf_tcp;
3488 mutex_enter(&tf->tf_lock);
3489 tcpnext = tcpp[0];
3490 if (tcpnext)
3491 tcpnext->tcp_ptpahn = &tcp->tcp_acceptor_hash;
3492 tcp->tcp_acceptor_hash = tcpnext;
3493 tcp->tcp_ptpahn = tcpp;
3494 tcpp[0] = tcp;
3495 tcp->tcp_acceptor_lockp = &tf->tf_lock; /* For tcp_*_hash_remove */
3496 mutex_exit(&tf->tf_lock);
3497 }
3498
3499 /*
3500 * Hash list removal routine for tcp_t structures.
3501 */
3502 void
3503 tcp_acceptor_hash_remove(tcp_t *tcp)
3504 {
3505 tcp_t *tcpnext;
3506 kmutex_t *lockp;
3507
3508 /*
3509 * Extract the lock pointer in case there are concurrent
3510 * hash_remove's for this instance.
3511 */
3512 lockp = tcp->tcp_acceptor_lockp;
3513
3514 if (tcp->tcp_ptpahn == NULL)
3515 return;
3516
3517 ASSERT(lockp != NULL);
3518 mutex_enter(lockp);
3519 if (tcp->tcp_ptpahn) {
3520 tcpnext = tcp->tcp_acceptor_hash;
3521 if (tcpnext) {
3522 tcpnext->tcp_ptpahn = tcp->tcp_ptpahn;
3523 tcp->tcp_acceptor_hash = NULL;
3524 }
3525 *tcp->tcp_ptpahn = tcpnext;
3526 tcp->tcp_ptpahn = NULL;
3527 }
3528 mutex_exit(lockp);
3529 tcp->tcp_acceptor_lockp = NULL;
3530 }
3531
3532 /*
3533 * Type three generator adapted from the random() function in 4.4 BSD:
3534 */
3535
3536 /*
3537 * Copyright (c) 1983, 1993
3538 * The Regents of the University of California. All rights reserved.
3539 *
3540 * Redistribution and use in source and binary forms, with or without
3541 * modification, are permitted provided that the following conditions
3542 * are met:
3543 * 1. Redistributions of source code must retain the above copyright
3544 * notice, this list of conditions and the following disclaimer.
3545 * 2. Redistributions in binary form must reproduce the above copyright
3546 * notice, this list of conditions and the following disclaimer in the
3547 * documentation and/or other materials provided with the distribution.
3548 * 3. All advertising materials mentioning features or use of this software
3549 * must display the following acknowledgement:
3550 * This product includes software developed by the University of
3551 * California, Berkeley and its contributors.
3552 * 4. Neither the name of the University nor the names of its contributors
3553 * may be used to endorse or promote products derived from this software
3554 * without specific prior written permission.
3555 *
3556 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
3557 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
3558 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
3559 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
3560 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
3561 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
3562 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
3563 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
3564 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
3565 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3566 * SUCH DAMAGE.
3567 */
3568
3569 /* Type 3 -- x**31 + x**3 + 1 */
3570 #define DEG_3 31
3571 #define SEP_3 3
3572
3573
3574 /* Protected by tcp_random_lock */
3575 static int tcp_randtbl[DEG_3 + 1];
3576
3577 static int *tcp_random_fptr = &tcp_randtbl[SEP_3 + 1];
3578 static int *tcp_random_rptr = &tcp_randtbl[1];
3579
3580 static int *tcp_random_state = &tcp_randtbl[1];
3581 static int *tcp_random_end_ptr = &tcp_randtbl[DEG_3 + 1];
3582
3583 kmutex_t tcp_random_lock;
3584
3585 void
3586 tcp_random_init(void)
3587 {
3588 int i;
3589 hrtime_t hrt;
3590 time_t wallclock;
3591 uint64_t result;
3592
3593 /*
3594 * Use high-res timer and current time for seed. Gethrtime() returns
3595 * a longlong, which may contain resolution down to nanoseconds.
3596 * The current time will either be a 32-bit or a 64-bit quantity.
3597 * XOR the two together in a 64-bit result variable.
3598 * Convert the result to a 32-bit value by multiplying the high-order
3599 * 32-bits by the low-order 32-bits.
3600 */
3601
3602 hrt = gethrtime();
3603 (void) drv_getparm(TIME, &wallclock);
3604 result = (uint64_t)wallclock ^ (uint64_t)hrt;
3605 mutex_enter(&tcp_random_lock);
3606 tcp_random_state[0] = ((result >> 32) & 0xffffffff) *
3607 (result & 0xffffffff);
3608
3609 for (i = 1; i < DEG_3; i++)
3610 tcp_random_state[i] = 1103515245 * tcp_random_state[i - 1]
3611 + 12345;
3612 tcp_random_fptr = &tcp_random_state[SEP_3];
3613 tcp_random_rptr = &tcp_random_state[0];
3614 mutex_exit(&tcp_random_lock);
3615 for (i = 0; i < 10 * DEG_3; i++)
3616 (void) tcp_random();
3617 }
3618
3619 /*
3620 * tcp_random: Return a random number in the range [1 - (128K + 1)].
3621 * This range is selected to be approximately centered on TCP_ISS / 2,
3622 * and easy to compute. We get this value by generating a 32-bit random
3623 * number, selecting out the high-order 17 bits, and then adding one so
3624 * that we never return zero.
3625 */
3626 int
3627 tcp_random(void)
3628 {
3629 int i;
3630
3631 mutex_enter(&tcp_random_lock);
3632 *tcp_random_fptr += *tcp_random_rptr;
3633
3634 /*
3635 * The high-order bits are more random than the low-order bits,
3636 * so we select out the high-order 17 bits and add one so that
3637 * we never return zero.
3638 */
3639 i = ((*tcp_random_fptr >> 15) & 0x1ffff) + 1;
3640 if (++tcp_random_fptr >= tcp_random_end_ptr) {
3641 tcp_random_fptr = tcp_random_state;
3642 ++tcp_random_rptr;
3643 } else if (++tcp_random_rptr >= tcp_random_end_ptr)
3644 tcp_random_rptr = tcp_random_state;
3645
3646 mutex_exit(&tcp_random_lock);
3647 return (i);
3648 }
3649
3650 /*
3651 * Split this function out so that if the secret changes, I'm okay.
3652 *
3653 * Initialize the tcp_iss_cookie and tcp_iss_key.
3654 */
3655
3656 #define PASSWD_SIZE 16 /* MUST be multiple of 4 */
3657
3658 void
3659 tcp_iss_key_init(uint8_t *phrase, int len, tcp_stack_t *tcps)
3660 {
3661 struct {
3662 int32_t current_time;
3663 uint32_t randnum;
3664 uint16_t pad;
3665 uint8_t ether[6];
3666 uint8_t passwd[PASSWD_SIZE];
3667 } tcp_iss_cookie;
3668 time_t t;
3669
3670 /*
3671 * Start with the current absolute time.
3672 */
3673 (void) drv_getparm(TIME, &t);
3674 tcp_iss_cookie.current_time = t;
3675
3676 /*
3677 * XXX - Need a more random number per RFC 1750, not this crap.
3678 * OTOH, if what follows is pretty random, then I'm in better shape.
3679 */
3680 tcp_iss_cookie.randnum = (uint32_t)(gethrtime() + tcp_random());
3681 tcp_iss_cookie.pad = 0x365c; /* Picked from HMAC pad values. */
3682
3683 /*
3684 * The cpu_type_info is pretty non-random. Ugggh. It does serve
3685 * as a good template.
3686 */
3687 bcopy(&cpu_list->cpu_type_info, &tcp_iss_cookie.passwd,
3688 min(PASSWD_SIZE, sizeof (cpu_list->cpu_type_info)));
3689
3690 /*
3691 * The pass-phrase. Normally this is supplied by user-called NDD.
3692 */
3693 bcopy(phrase, &tcp_iss_cookie.passwd, min(PASSWD_SIZE, len));
3694
3695 /*
3696 * See 4010593 if this section becomes a problem again,
3697 * but the local ethernet address is useful here.
3698 */
3699 (void) localetheraddr(NULL,
3700 (struct ether_addr *)&tcp_iss_cookie.ether);
3701
3702 /*
3703 * Hash 'em all together. The MD5Final is called per-connection.
3704 */
3705 mutex_enter(&tcps->tcps_iss_key_lock);
3706 MD5Init(&tcps->tcps_iss_key);
3707 MD5Update(&tcps->tcps_iss_key, (uchar_t *)&tcp_iss_cookie,
3708 sizeof (tcp_iss_cookie));
3709 mutex_exit(&tcps->tcps_iss_key_lock);
3710 }
3711
3712 /*
3713 * Called by IP when IP is loaded into the kernel
3714 */
3715 void
3716 tcp_ddi_g_init(void)
3717 {
3718 tcp_timercache = kmem_cache_create("tcp_timercache",
3719 sizeof (tcp_timer_t) + sizeof (mblk_t), 0,
3720 NULL, NULL, NULL, NULL, NULL, 0);
3721
3722 tcp_notsack_blk_cache = kmem_cache_create("tcp_notsack_blk_cache",
3723 sizeof (notsack_blk_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
3724
3725 mutex_init(&tcp_random_lock, NULL, MUTEX_DEFAULT, NULL);
3726
3727 /* Initialize the random number generator */
3728 tcp_random_init();
3729
3730 /* A single callback independently of how many netstacks we have */
3731 ip_squeue_init(tcp_squeue_add);
3732
3733 tcp_g_kstat = tcp_g_kstat_init(&tcp_g_statistics);
3734
3735 tcp_squeue_flag = tcp_squeue_switch(tcp_squeue_wput);
3736
3737 /*
3738 * We want to be informed each time a stack is created or
3739 * destroyed in the kernel, so we can maintain the
3740 * set of tcp_stack_t's.
3741 */
3742 netstack_register(NS_TCP, tcp_stack_init, NULL, tcp_stack_fini);
3743 }
3744
3745
3746 #define INET_NAME "ip"
3747
3748 /*
3749 * Initialize the TCP stack instance.
3750 */
3751 static void *
3752 tcp_stack_init(netstackid_t stackid, netstack_t *ns)
3753 {
3754 tcp_stack_t *tcps;
3755 int i;
3756 int error = 0;
3757 major_t major;
3758 size_t arrsz;
3759
3760 tcps = (tcp_stack_t *)kmem_zalloc(sizeof (*tcps), KM_SLEEP);
3761 tcps->tcps_netstack = ns;
3762
3763 /* Initialize locks */
3764 mutex_init(&tcps->tcps_iss_key_lock, NULL, MUTEX_DEFAULT, NULL);
3765 mutex_init(&tcps->tcps_epriv_port_lock, NULL, MUTEX_DEFAULT, NULL);
3766
3767 tcps->tcps_g_num_epriv_ports = TCP_NUM_EPRIV_PORTS;
3768 tcps->tcps_g_epriv_ports[0] = ULP_DEF_EPRIV_PORT1;
3769 tcps->tcps_g_epriv_ports[1] = ULP_DEF_EPRIV_PORT2;
3770 tcps->tcps_min_anonpriv_port = 512;
3771
3772 tcps->tcps_bind_fanout = kmem_zalloc(sizeof (tf_t) *
3773 TCP_BIND_FANOUT_SIZE, KM_SLEEP);
3774 tcps->tcps_acceptor_fanout = kmem_zalloc(sizeof (tf_t) *
3775 TCP_ACCEPTOR_FANOUT_SIZE, KM_SLEEP);
3776
3777 for (i = 0; i < TCP_BIND_FANOUT_SIZE; i++) {
3778 mutex_init(&tcps->tcps_bind_fanout[i].tf_lock, NULL,
3779 MUTEX_DEFAULT, NULL);
3780 }
3781
3782 for (i = 0; i < TCP_ACCEPTOR_FANOUT_SIZE; i++) {
3783 mutex_init(&tcps->tcps_acceptor_fanout[i].tf_lock, NULL,
3784 MUTEX_DEFAULT, NULL);
3785 }
3786
3787 /* TCP's IPsec code calls the packet dropper. */
3788 ip_drop_register(&tcps->tcps_dropper, "TCP IPsec policy enforcement");
3789
3790 arrsz = tcp_propinfo_count * sizeof (mod_prop_info_t);
3791 tcps->tcps_propinfo_tbl = (mod_prop_info_t *)kmem_alloc(arrsz,
3792 KM_SLEEP);
3793 bcopy(tcp_propinfo_tbl, tcps->tcps_propinfo_tbl, arrsz);
3794
3795 /*
3796 * Note: To really walk the device tree you need the devinfo
3797 * pointer to your device which is only available after probe/attach.
3798 * The following is safe only because it uses ddi_root_node()
3799 */
3800 tcp_max_optsize = optcom_max_optsize(tcp_opt_obj.odb_opt_des_arr,
3801 tcp_opt_obj.odb_opt_arr_cnt);
3802
3803 /*
3804 * Initialize RFC 1948 secret values. This will probably be reset once
3805 * by the boot scripts.
3806 *
3807 * Use NULL name, as the name is caught by the new lockstats.
3808 *
3809 * Initialize with some random, non-guessable string, like the global
3810 * T_INFO_ACK.
3811 */
3812
3813 tcp_iss_key_init((uint8_t *)&tcp_g_t_info_ack,
3814 sizeof (tcp_g_t_info_ack), tcps);
3815
3816 tcps->tcps_kstat = tcp_kstat2_init(stackid);
3817 tcps->tcps_mibkp = tcp_kstat_init(stackid);
3818
3819 major = mod_name_to_major(INET_NAME);
3820 error = ldi_ident_from_major(major, &tcps->tcps_ldi_ident);
3821 ASSERT(error == 0);
3822 tcps->tcps_ixa_cleanup_mp = allocb_wait(0, BPRI_MED, STR_NOSIG, NULL);
3823 ASSERT(tcps->tcps_ixa_cleanup_mp != NULL);
3824 cv_init(&tcps->tcps_ixa_cleanup_ready_cv, NULL, CV_DEFAULT, NULL);
3825 cv_init(&tcps->tcps_ixa_cleanup_done_cv, NULL, CV_DEFAULT, NULL);
3826 mutex_init(&tcps->tcps_ixa_cleanup_lock, NULL, MUTEX_DEFAULT, NULL);
3827
3828 mutex_init(&tcps->tcps_reclaim_lock, NULL, MUTEX_DEFAULT, NULL);
3829 tcps->tcps_reclaim = B_FALSE;
3830 tcps->tcps_reclaim_tid = 0;
3831 tcps->tcps_reclaim_period = tcps->tcps_rexmit_interval_max;
3832
3833 /*
3834 * ncpus is the current number of CPUs, which can be bigger than
3835 * boot_ncpus. But we don't want to use ncpus to allocate all the
3836 * tcp_stats_cpu_t at system boot up time since it will be 1. While
3837 * we handle adding CPU in tcp_cpu_update(), it will be slow if
3838 * there are many CPUs as we will be adding them 1 by 1.
3839 *
3840 * Note that tcps_sc_cnt never decreases and the tcps_sc[x] pointers
3841 * are not freed until the stack is going away. So there is no need
3842 * to grab a lock to access the per CPU tcps_sc[x] pointer.
3843 */
3844 mutex_enter(&cpu_lock);
3845 tcps->tcps_sc_cnt = MAX(ncpus, boot_ncpus);
3846 mutex_exit(&cpu_lock);
3847 tcps->tcps_sc = kmem_zalloc(max_ncpus * sizeof (tcp_stats_cpu_t *),
3848 KM_SLEEP);
3849 for (i = 0; i < tcps->tcps_sc_cnt; i++) {
3850 tcps->tcps_sc[i] = kmem_zalloc(sizeof (tcp_stats_cpu_t),
3851 KM_SLEEP);
3852 }
3853
3854 mutex_init(&tcps->tcps_listener_conf_lock, NULL, MUTEX_DEFAULT, NULL);
3855 list_create(&tcps->tcps_listener_conf, sizeof (tcp_listener_t),
3856 offsetof(tcp_listener_t, tl_link));
3857
3858 tcps->tcps_default_cc_algo = cc_load_algo(CC_DEFAULT_ALGO_NAME);
3859 VERIFY3P(tcps->tcps_default_cc_algo, !=, NULL);
3860
3861 return (tcps);
3862 }
3863
3864 /*
3865 * Called when the IP module is about to be unloaded.
3866 */
3867 void
3868 tcp_ddi_g_destroy(void)
3869 {
3870 tcp_g_kstat_fini(tcp_g_kstat);
3871 tcp_g_kstat = NULL;
3872 bzero(&tcp_g_statistics, sizeof (tcp_g_statistics));
3873
3874 mutex_destroy(&tcp_random_lock);
3875
3876 kmem_cache_destroy(tcp_timercache);
3877 kmem_cache_destroy(tcp_notsack_blk_cache);
3878
3879 netstack_unregister(NS_TCP);
3880 }
3881
3882 /*
3883 * Free the TCP stack instance.
3884 */
3885 static void
3886 tcp_stack_fini(netstackid_t stackid, void *arg)
3887 {
3888 tcp_stack_t *tcps = (tcp_stack_t *)arg;
3889 int i;
3890
3891 freeb(tcps->tcps_ixa_cleanup_mp);
3892 tcps->tcps_ixa_cleanup_mp = NULL;
3893 cv_destroy(&tcps->tcps_ixa_cleanup_ready_cv);
3894 cv_destroy(&tcps->tcps_ixa_cleanup_done_cv);
3895 mutex_destroy(&tcps->tcps_ixa_cleanup_lock);
3896
3897 /*
3898 * Set tcps_reclaim to false tells tcp_reclaim_timer() not to restart
3899 * the timer.
3900 */
3901 mutex_enter(&tcps->tcps_reclaim_lock);
3902 tcps->tcps_reclaim = B_FALSE;
3903 mutex_exit(&tcps->tcps_reclaim_lock);
3904 if (tcps->tcps_reclaim_tid != 0)
3905 (void) untimeout(tcps->tcps_reclaim_tid);
3906 mutex_destroy(&tcps->tcps_reclaim_lock);
3907
3908 tcp_listener_conf_cleanup(tcps);
3909
3910 for (i = 0; i < tcps->tcps_sc_cnt; i++)
3911 kmem_free(tcps->tcps_sc[i], sizeof (tcp_stats_cpu_t));
3912 kmem_free(tcps->tcps_sc, max_ncpus * sizeof (tcp_stats_cpu_t *));
3913
3914 kmem_free(tcps->tcps_propinfo_tbl,
3915 tcp_propinfo_count * sizeof (mod_prop_info_t));
3916 tcps->tcps_propinfo_tbl = NULL;
3917
3918 for (i = 0; i < TCP_BIND_FANOUT_SIZE; i++) {
3919 ASSERT(tcps->tcps_bind_fanout[i].tf_tcp == NULL);
3920 mutex_destroy(&tcps->tcps_bind_fanout[i].tf_lock);
3921 }
3922
3923 for (i = 0; i < TCP_ACCEPTOR_FANOUT_SIZE; i++) {
3924 ASSERT(tcps->tcps_acceptor_fanout[i].tf_tcp == NULL);
3925 mutex_destroy(&tcps->tcps_acceptor_fanout[i].tf_lock);
3926 }
3927
3928 kmem_free(tcps->tcps_bind_fanout, sizeof (tf_t) * TCP_BIND_FANOUT_SIZE);
3929 tcps->tcps_bind_fanout = NULL;
3930
3931 kmem_free(tcps->tcps_acceptor_fanout, sizeof (tf_t) *
3932 TCP_ACCEPTOR_FANOUT_SIZE);
3933 tcps->tcps_acceptor_fanout = NULL;
3934
3935 mutex_destroy(&tcps->tcps_iss_key_lock);
3936 mutex_destroy(&tcps->tcps_epriv_port_lock);
3937
3938 ip_drop_unregister(&tcps->tcps_dropper);
3939
3940 tcp_kstat2_fini(stackid, tcps->tcps_kstat);
3941 tcps->tcps_kstat = NULL;
3942
3943 tcp_kstat_fini(stackid, tcps->tcps_mibkp);
3944 tcps->tcps_mibkp = NULL;
3945
3946 ldi_ident_release(tcps->tcps_ldi_ident);
3947 kmem_free(tcps, sizeof (*tcps));
3948 }
3949
3950 /*
3951 * Generate ISS, taking into account NDD changes may happen halfway through.
3952 * (If the iss is not zero, set it.)
3953 */
3954
3955 static void
3956 tcp_iss_init(tcp_t *tcp)
3957 {
3958 MD5_CTX context;
3959 struct { uint32_t ports; in6_addr_t src; in6_addr_t dst; } arg;
3960 uint32_t answer[4];
3961 tcp_stack_t *tcps = tcp->tcp_tcps;
3962 conn_t *connp = tcp->tcp_connp;
3963
3964 tcps->tcps_iss_incr_extra += (tcps->tcps_iss_incr >> 1);
3965 tcp->tcp_iss = tcps->tcps_iss_incr_extra;
3966 switch (tcps->tcps_strong_iss) {
3967 case 2:
3968 mutex_enter(&tcps->tcps_iss_key_lock);
3969 context = tcps->tcps_iss_key;
3970 mutex_exit(&tcps->tcps_iss_key_lock);
3971 arg.ports = connp->conn_ports;
3972 arg.src = connp->conn_laddr_v6;
3973 arg.dst = connp->conn_faddr_v6;
3974 MD5Update(&context, (uchar_t *)&arg, sizeof (arg));
3975 MD5Final((uchar_t *)answer, &context);
3976 tcp->tcp_iss += answer[0] ^ answer[1] ^ answer[2] ^ answer[3];
3977 /*
3978 * Now that we've hashed into a unique per-connection sequence
3979 * space, add a random increment per strong_iss == 1. So I
3980 * guess we'll have to...
3981 */
3982 /* FALLTHRU */
3983 case 1:
3984 tcp->tcp_iss += (gethrtime() >> ISS_NSEC_SHT) + tcp_random();
3985 break;
3986 default:
3987 tcp->tcp_iss += (uint32_t)gethrestime_sec() *
3988 tcps->tcps_iss_incr;
3989 break;
3990 }
3991 tcp->tcp_valid_bits = TCP_ISS_VALID;
3992 tcp->tcp_fss = tcp->tcp_iss - 1;
3993 tcp->tcp_suna = tcp->tcp_iss;
3994 tcp->tcp_snxt = tcp->tcp_iss + 1;
3995 tcp->tcp_rexmit_nxt = tcp->tcp_snxt;
3996 tcp->tcp_csuna = tcp->tcp_snxt;
3997 }
3998
3999 /*
4000 * tcp_{set,clr}qfull() functions are used to either set or clear QFULL
4001 * on the specified backing STREAMS q. Note, the caller may make the
4002 * decision to call based on the tcp_t.tcp_flow_stopped value which
4003 * when check outside the q's lock is only an advisory check ...
4004 */
4005 void
4006 tcp_setqfull(tcp_t *tcp)
4007 {
4008 tcp_stack_t *tcps = tcp->tcp_tcps;
4009 conn_t *connp = tcp->tcp_connp;
4010
4011 if (tcp->tcp_closed)
4012 return;
4013
4014 conn_setqfull(connp, &tcp->tcp_flow_stopped);
4015 if (tcp->tcp_flow_stopped)
4016 TCP_STAT(tcps, tcp_flwctl_on);
4017 }
4018
4019 void
4020 tcp_clrqfull(tcp_t *tcp)
4021 {
4022 conn_t *connp = tcp->tcp_connp;
4023
4024 if (tcp->tcp_closed)
4025 return;
4026 conn_clrqfull(connp, &tcp->tcp_flow_stopped);
4027 }
4028
4029 static int
4030 tcp_squeue_switch(int val)
4031 {
4032 int rval = SQ_FILL;
4033
4034 switch (val) {
4035 case 1:
4036 rval = SQ_NODRAIN;
4037 break;
4038 case 2:
4039 rval = SQ_PROCESS;
4040 break;
4041 default:
4042 break;
4043 }
4044 return (rval);
4045 }
4046
4047 /*
4048 * This is called once for each squeue - globally for all stack
4049 * instances.
4050 */
4051 static void
4052 tcp_squeue_add(squeue_t *sqp)
4053 {
4054 tcp_squeue_priv_t *tcp_time_wait = kmem_zalloc(
4055 sizeof (tcp_squeue_priv_t), KM_SLEEP);
4056
4057 *squeue_getprivate(sqp, SQPRIVATE_TCP) = (intptr_t)tcp_time_wait;
4058 if (tcp_free_list_max_cnt == 0) {
4059 int tcp_ncpus = ((boot_max_ncpus == -1) ?
4060 max_ncpus : boot_max_ncpus);
4061
4062 /*
4063 * Limit number of entries to 1% of availble memory / tcp_ncpus
4064 */
4065 tcp_free_list_max_cnt = (freemem * PAGESIZE) /
4066 (tcp_ncpus * sizeof (tcp_t) * 100);
4067 }
4068 tcp_time_wait->tcp_free_list_cnt = 0;
4069 }
4070 /*
4071 * Return unix error is tli error is TSYSERR, otherwise return a negative
4072 * tli error.
4073 */
4074 int
4075 tcp_do_bind(conn_t *connp, struct sockaddr *sa, socklen_t len, cred_t *cr,
4076 boolean_t bind_to_req_port_only)
4077 {
4078 int error;
4079 tcp_t *tcp = connp->conn_tcp;
4080
4081 if (tcp->tcp_state >= TCPS_BOUND) {
4082 if (connp->conn_debug) {
4083 (void) strlog(TCP_MOD_ID, 0, 1, SL_ERROR|SL_TRACE,
4084 "tcp_bind: bad state, %d", tcp->tcp_state);
4085 }
4086 return (-TOUTSTATE);
4087 }
4088
4089 error = tcp_bind_check(connp, sa, len, cr, bind_to_req_port_only);
4090 if (error != 0)
4091 return (error);
4092
4093 ASSERT(tcp->tcp_state == TCPS_BOUND);
4094 tcp->tcp_conn_req_max = 0;
4095 return (0);
4096 }
4097
4098 /*
4099 * If the return value from this function is positive, it's a UNIX error.
4100 * Otherwise, if it's negative, then the absolute value is a TLI error.
4101 * the TPI routine tcp_tpi_connect() is a wrapper function for this.
4102 */
4103 int
4104 tcp_do_connect(conn_t *connp, const struct sockaddr *sa, socklen_t len,
4105 cred_t *cr, pid_t pid)
4106 {
4107 tcp_t *tcp = connp->conn_tcp;
4108 sin_t *sin = (sin_t *)sa;
4109 sin6_t *sin6 = (sin6_t *)sa;
4110 ipaddr_t *dstaddrp;
4111 in_port_t dstport;
4112 uint_t srcid;
4113 int error;
4114 uint32_t mss;
4115 mblk_t *syn_mp;
4116 tcp_stack_t *tcps = tcp->tcp_tcps;
4117 int32_t oldstate;
4118 ip_xmit_attr_t *ixa = connp->conn_ixa;
4119
4120 oldstate = tcp->tcp_state;
4121
4122 switch (len) {
4123 default:
4124 /*
4125 * Should never happen
4126 */
4127 return (EINVAL);
4128
4129 case sizeof (sin_t):
4130 sin = (sin_t *)sa;
4131 if (sin->sin_port == 0) {
4132 return (-TBADADDR);
4133 }
4134 if (connp->conn_ipv6_v6only) {
4135 return (EAFNOSUPPORT);
4136 }
4137 break;
4138
4139 case sizeof (sin6_t):
4140 sin6 = (sin6_t *)sa;
4141 if (sin6->sin6_port == 0) {
4142 return (-TBADADDR);
4143 }
4144 break;
4145 }
4146 /*
4147 * If we're connecting to an IPv4-mapped IPv6 address, we need to
4148 * make sure that the conn_ipversion is IPV4_VERSION. We
4149 * need to this before we call tcp_bindi() so that the port lookup
4150 * code will look for ports in the correct port space (IPv4 and
4151 * IPv6 have separate port spaces).
4152 */
4153 if (connp->conn_family == AF_INET6 &&
4154 connp->conn_ipversion == IPV6_VERSION &&
4155 IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
4156 if (connp->conn_ipv6_v6only)
4157 return (EADDRNOTAVAIL);
4158
4159 connp->conn_ipversion = IPV4_VERSION;
4160 }
4161
4162 switch (tcp->tcp_state) {
4163 case TCPS_LISTEN:
4164 /*
4165 * Listening sockets are not allowed to issue connect().
4166 */
4167 if (IPCL_IS_NONSTR(connp))
4168 return (EOPNOTSUPP);
4169 /* FALLTHRU */
4170 case TCPS_IDLE:
4171 /*
4172 * We support quick connect, refer to comments in
4173 * tcp_connect_*()
4174 */
4175 /* FALLTHRU */
4176 case TCPS_BOUND:
4177 break;
4178 default:
4179 return (-TOUTSTATE);
4180 }
4181
4182 /*
4183 * We update our cred/cpid based on the caller of connect
4184 */
4185 if (connp->conn_cred != cr) {
4186 crhold(cr);
4187 crfree(connp->conn_cred);
4188 connp->conn_cred = cr;
4189 }
4190 connp->conn_cpid = pid;
4191
4192 /* Cache things in the ixa without any refhold */
4193 ASSERT(!(ixa->ixa_free_flags & IXA_FREE_CRED));
4194 ixa->ixa_cred = cr;
4195 ixa->ixa_cpid = pid;
4196 if (is_system_labeled()) {
4197 /* We need to restart with a label based on the cred */
4198 ip_xmit_attr_restore_tsl(ixa, ixa->ixa_cred);
4199 }
4200
4201 if (connp->conn_family == AF_INET6) {
4202 if (!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
4203 error = tcp_connect_ipv6(tcp, &sin6->sin6_addr,
4204 sin6->sin6_port, sin6->sin6_flowinfo,
4205 sin6->__sin6_src_id, sin6->sin6_scope_id);
4206 } else {
4207 /*
4208 * Destination adress is mapped IPv6 address.
4209 * Source bound address should be unspecified or
4210 * IPv6 mapped address as well.
4211 */
4212 if (!IN6_IS_ADDR_UNSPECIFIED(
4213 &connp->conn_bound_addr_v6) &&
4214 !IN6_IS_ADDR_V4MAPPED(&connp->conn_bound_addr_v6)) {
4215 return (EADDRNOTAVAIL);
4216 }
4217 dstaddrp = &V4_PART_OF_V6((sin6->sin6_addr));
4218 dstport = sin6->sin6_port;
4219 srcid = sin6->__sin6_src_id;
4220 error = tcp_connect_ipv4(tcp, dstaddrp, dstport,
4221 srcid);
4222 }
4223 } else {
4224 dstaddrp = &sin->sin_addr.s_addr;
4225 dstport = sin->sin_port;
4226 srcid = 0;
4227 error = tcp_connect_ipv4(tcp, dstaddrp, dstport, srcid);
4228 }
4229
4230 if (error != 0)
4231 goto connect_failed;
4232
4233 CL_INET_CONNECT(connp, B_TRUE, error);
4234 if (error != 0)
4235 goto connect_failed;
4236
4237 /* connect succeeded */
4238 TCPS_BUMP_MIB(tcps, tcpActiveOpens);
4239 tcp->tcp_active_open = 1;
4240
4241 /*
4242 * tcp_set_destination() does not adjust for TCP/IP header length.
4243 */
4244 mss = tcp->tcp_mss - connp->conn_ht_iphc_len;
4245
4246 /*
4247 * Just make sure our rwnd is at least rcvbuf * MSS large, and round up
4248 * to the nearest MSS.
4249 *
4250 * We do the round up here because we need to get the interface MTU
4251 * first before we can do the round up.
4252 */
4253 tcp->tcp_rwnd = connp->conn_rcvbuf;
4254 tcp->tcp_rwnd = MAX(MSS_ROUNDUP(tcp->tcp_rwnd, mss),
4255 tcps->tcps_recv_hiwat_minmss * mss);
4256 connp->conn_rcvbuf = tcp->tcp_rwnd;
4257 tcp_set_ws_value(tcp);
4258 tcp->tcp_tcpha->tha_win = htons(tcp->tcp_rwnd >> tcp->tcp_rcv_ws);
4259 if (tcp->tcp_rcv_ws > 0 || tcps->tcps_wscale_always)
4260 tcp->tcp_snd_ws_ok = B_TRUE;
4261
4262 /*
4263 * Set tcp_snd_ts_ok to true
4264 * so that tcp_xmit_mp will
4265 * include the timestamp
4266 * option in the SYN segment.
4267 */
4268 if (tcps->tcps_tstamp_always ||
4269 (tcp->tcp_rcv_ws && tcps->tcps_tstamp_if_wscale)) {
4270 tcp->tcp_snd_ts_ok = B_TRUE;
4271 }
4272
4273 /*
4274 * Note that tcp_snd_sack_ok can be set in tcp_set_destination() if
4275 * the SACK metric is set. So here we just check the per stack SACK
4276 * permitted param.
4277 */
4278 if (tcps->tcps_sack_permitted == 2) {
4279 ASSERT(tcp->tcp_num_sack_blk == 0);
4280 ASSERT(tcp->tcp_notsack_list == NULL);
4281 tcp->tcp_snd_sack_ok = B_TRUE;
4282 }
4283
4284 /*
4285 * Should we use ECN? Note that the current
4286 * default value (SunOS 5.9) of tcp_ecn_permitted
4287 * is 1. The reason for doing this is that there
4288 * are equipments out there that will drop ECN
4289 * enabled IP packets. Setting it to 1 avoids
4290 * compatibility problems.
4291 */
4292 if (tcps->tcps_ecn_permitted == 2)
4293 tcp->tcp_ecn_ok = B_TRUE;
4294
4295 /* Trace change from BOUND -> SYN_SENT here */
4296 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
4297 connp->conn_ixa, void, NULL, tcp_t *, tcp, void, NULL,
4298 int32_t, TCPS_BOUND);
4299
4300 TCP_TIMER_RESTART(tcp, tcp->tcp_rto);
4301 syn_mp = tcp_xmit_mp(tcp, NULL, 0, NULL, NULL,
4302 tcp->tcp_iss, B_FALSE, NULL, B_FALSE);
4303 if (syn_mp != NULL) {
4304 /*
4305 * We must bump the generation before sending the syn
4306 * to ensure that we use the right generation in case
4307 * this thread issues a "connected" up call.
4308 */
4309 SOCK_CONNID_BUMP(tcp->tcp_connid);
4310 /*
4311 * DTrace sending the first SYN as a
4312 * tcp:::connect-request event.
4313 */
4314 DTRACE_TCP5(connect__request, mblk_t *, NULL,
4315 ip_xmit_attr_t *, connp->conn_ixa,
4316 void_ip_t *, syn_mp->b_rptr, tcp_t *, tcp,
4317 tcph_t *,
4318 &syn_mp->b_rptr[connp->conn_ixa->ixa_ip_hdr_length]);
4319 tcp_send_data(tcp, syn_mp);
4320 }
4321
4322 if (tcp->tcp_conn.tcp_opts_conn_req != NULL)
4323 tcp_close_mpp(&tcp->tcp_conn.tcp_opts_conn_req);
4324 return (0);
4325
4326 connect_failed:
4327 connp->conn_faddr_v6 = ipv6_all_zeros;
4328 connp->conn_fport = 0;
4329 tcp->tcp_state = oldstate;
4330 if (tcp->tcp_conn.tcp_opts_conn_req != NULL)
4331 tcp_close_mpp(&tcp->tcp_conn.tcp_opts_conn_req);
4332 return (error);
4333 }
4334
4335 int
4336 tcp_do_listen(conn_t *connp, struct sockaddr *sa, socklen_t len,
4337 int backlog, cred_t *cr, boolean_t bind_to_req_port_only)
4338 {
4339 tcp_t *tcp = connp->conn_tcp;
4340 int error = 0;
4341 tcp_stack_t *tcps = tcp->tcp_tcps;
4342 int32_t oldstate;
4343
4344 /* All Solaris components should pass a cred for this operation. */
4345 ASSERT(cr != NULL);
4346
4347 if (tcp->tcp_state >= TCPS_BOUND) {
4348 if ((tcp->tcp_state == TCPS_BOUND ||
4349 tcp->tcp_state == TCPS_LISTEN) && backlog > 0) {
4350 /*
4351 * Handle listen() increasing backlog.
4352 * This is more "liberal" then what the TPI spec
4353 * requires but is needed to avoid a t_unbind
4354 * when handling listen() since the port number
4355 * might be "stolen" between the unbind and bind.
4356 */
4357 goto do_listen;
4358 }
4359 if (connp->conn_debug) {
4360 (void) strlog(TCP_MOD_ID, 0, 1, SL_ERROR|SL_TRACE,
4361 "tcp_listen: bad state, %d", tcp->tcp_state);
4362 }
4363 return (-TOUTSTATE);
4364 } else {
4365 sin6_t addr;
4366 sin_t *sin;
4367 sin6_t *sin6;
4368
4369 if (sa == NULL) {
4370 ASSERT(IPCL_IS_NONSTR(connp));
4371 /* Do an implicit bind: Request for a generic port. */
4372 if (connp->conn_family == AF_INET) {
4373 len = sizeof (sin_t);
4374 sin = (sin_t *)&addr;
4375 *sin = sin_null;
4376 sin->sin_family = AF_INET;
4377 } else {
4378 ASSERT(connp->conn_family == AF_INET6);
4379 len = sizeof (sin6_t);
4380 sin6 = (sin6_t *)&addr;
4381 *sin6 = sin6_null;
4382 sin6->sin6_family = AF_INET6;
4383 }
4384 sa = (struct sockaddr *)&addr;
4385 }
4386
4387 error = tcp_bind_check(connp, sa, len, cr,
4388 bind_to_req_port_only);
4389 if (error)
4390 return (error);
4391 /* Fall through and do the fanout insertion */
4392 }
4393
4394 do_listen:
4395 ASSERT(tcp->tcp_state == TCPS_BOUND || tcp->tcp_state == TCPS_LISTEN);
4396 tcp->tcp_conn_req_max = backlog;
4397 if (tcp->tcp_conn_req_max) {
4398 if (tcp->tcp_conn_req_max < tcps->tcps_conn_req_min)
4399 tcp->tcp_conn_req_max = tcps->tcps_conn_req_min;
4400 if (tcp->tcp_conn_req_max > tcps->tcps_conn_req_max_q)
4401 tcp->tcp_conn_req_max = tcps->tcps_conn_req_max_q;
4402 /*
4403 * If this is a listener, do not reset the eager list
4404 * and other stuffs. Note that we don't check if the
4405 * existing eager list meets the new tcp_conn_req_max
4406 * requirement.
4407 */
4408 if (tcp->tcp_state != TCPS_LISTEN) {
4409 tcp->tcp_state = TCPS_LISTEN;
4410 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
4411 connp->conn_ixa, void, NULL, tcp_t *, tcp,
4412 void, NULL, int32_t, TCPS_BOUND);
4413 /* Initialize the chain. Don't need the eager_lock */
4414 tcp->tcp_eager_next_q0 = tcp->tcp_eager_prev_q0 = tcp;
4415 tcp->tcp_eager_next_drop_q0 = tcp;
4416 tcp->tcp_eager_prev_drop_q0 = tcp;
4417 tcp->tcp_second_ctimer_threshold =
4418 tcps->tcps_ip_abort_linterval;
4419 }
4420 }
4421
4422 /*
4423 * We need to make sure that the conn_recv is set to a non-null
4424 * value before we insert the conn into the classifier table.
4425 * This is to avoid a race with an incoming packet which does an
4426 * ipcl_classify().
4427 * We initially set it to tcp_input_listener_unbound to try to
4428 * pick a good squeue for the listener when the first SYN arrives.
4429 * tcp_input_listener_unbound sets it to tcp_input_listener on that
4430 * first SYN.
4431 */
4432 connp->conn_recv = tcp_input_listener_unbound;
4433
4434 /* Insert the listener in the classifier table */
4435 error = ip_laddr_fanout_insert(connp);
4436 if (error != 0) {
4437 /* Undo the bind - release the port number */
4438 oldstate = tcp->tcp_state;
4439 tcp->tcp_state = TCPS_IDLE;
4440 DTRACE_TCP6(state__change, void, NULL, ip_xmit_attr_t *,
4441 connp->conn_ixa, void, NULL, tcp_t *, tcp, void, NULL,
4442 int32_t, oldstate);
4443 connp->conn_bound_addr_v6 = ipv6_all_zeros;
4444
4445 connp->conn_laddr_v6 = ipv6_all_zeros;
4446 connp->conn_saddr_v6 = ipv6_all_zeros;
4447 connp->conn_ports = 0;
4448
4449 if (connp->conn_anon_port) {
4450 zone_t *zone;
4451
4452 zone = crgetzone(cr);
4453 connp->conn_anon_port = B_FALSE;
4454 (void) tsol_mlp_anon(zone, connp->conn_mlp_type,
4455 connp->conn_proto, connp->conn_lport, B_FALSE);
4456 }
4457 connp->conn_mlp_type = mlptSingle;
4458
4459 tcp_bind_hash_remove(tcp);
4460 return (error);
4461 } else {
4462 /*
4463 * If there is a connection limit, allocate and initialize
4464 * the counter struct. Note that since listen can be called
4465 * multiple times, the struct may have been allready allocated.
4466 */
4467 if (!list_is_empty(&tcps->tcps_listener_conf) &&
4468 tcp->tcp_listen_cnt == NULL) {
4469 tcp_listen_cnt_t *tlc;
4470 uint32_t ratio;
4471
4472 ratio = tcp_find_listener_conf(tcps,
4473 ntohs(connp->conn_lport));
4474 if (ratio != 0) {
4475 uint32_t mem_ratio, tot_buf;
4476
4477 tlc = kmem_alloc(sizeof (tcp_listen_cnt_t),
4478 KM_SLEEP);
4479 /*
4480 * Calculate the connection limit based on
4481 * the configured ratio and maxusers. Maxusers
4482 * are calculated based on memory size,
4483 * ~ 1 user per MB. Note that the conn_rcvbuf
4484 * and conn_sndbuf may change after a
4485 * connection is accepted. So what we have
4486 * is only an approximation.
4487 */
4488 if ((tot_buf = connp->conn_rcvbuf +
4489 connp->conn_sndbuf) < MB) {
4490 mem_ratio = MB / tot_buf;
4491 tlc->tlc_max = maxusers / ratio *
4492 mem_ratio;
4493 } else {
4494 mem_ratio = tot_buf / MB;
4495 tlc->tlc_max = maxusers / ratio /
4496 mem_ratio;
4497 }
4498 /* At least we should allow two connections! */
4499 if (tlc->tlc_max <= tcp_min_conn_listener)
4500 tlc->tlc_max = tcp_min_conn_listener;
4501 tlc->tlc_cnt = 1;
4502 tlc->tlc_drop = 0;
4503 tcp->tcp_listen_cnt = tlc;
4504 }
4505 }
4506 }
4507 return (error);
4508 }