1/*
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93
34 * $FreeBSD: head/sys/kern/uipc_sockbuf.c 111119 2003-02-19 05:47:46Z imp $
35 */
36
37#include "opt_mac.h"
38#include "opt_param.h"
39
40#include <sys/param.h>
41#include <sys/aio.h> /* for aio_swake proto */
42#include <sys/domain.h>
43#include <sys/event.h>
44#include <sys/file.h> /* for maxfiles */
45#include <sys/kernel.h>
46#include <sys/lock.h>
47#include <sys/mac.h>
48#include <sys/malloc.h>
49#include <sys/mbuf.h>
50#include <sys/mutex.h>
51#include <sys/proc.h>
52#include <sys/protosw.h>
53#include <sys/resourcevar.h>
54#include <sys/signalvar.h>
55#include <sys/socket.h>
56#include <sys/socketvar.h>
57#include <sys/stat.h>
58#include <sys/sysctl.h>
59#include <sys/systm.h>
60
61int maxsockets;
62
63void (*aio_swake)(struct socket *, struct sockbuf *);
64
65/*
66 * Primitive routines for operating on sockets and socket buffers
67 */
68
69u_long sb_max = SB_MAX;
70u_long sb_max_adj =
71 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */
72
73static u_long sb_efficiency = 8; /* parameter for sbreserve() */
74
75/*
76 * Procedures to manipulate state flags of socket
77 * and do appropriate wakeups. Normal sequence from the
78 * active (originating) side is that soisconnecting() is
79 * called during processing of connect() call,
80 * resulting in an eventual call to soisconnected() if/when the
81 * connection is established. When the connection is torn down
82 * soisdisconnecting() is called during processing of disconnect() call,
83 * and soisdisconnected() is called when the connection to the peer
84 * is totally severed. The semantics of these routines are such that
85 * connectionless protocols can call soisconnected() and soisdisconnected()
86 * only, bypassing the in-progress calls when setting up a ``connection''
87 * takes no time.
88 *
89 * From the passive side, a socket is created with
90 * two queues of sockets: so_incomp for connections in progress
91 * and so_comp for connections already made and awaiting user acceptance.
92 * As a protocol is preparing incoming connections, it creates a socket
93 * structure queued on so_incomp by calling sonewconn(). When the connection
94 * is established, soisconnected() is called, and transfers the
95 * socket structure to so_comp, making it available to accept().
96 *
97 * If a socket is closed with sockets on either
98 * so_incomp or so_comp, these sockets are dropped.
99 *
100 * If higher level protocols are implemented in
101 * the kernel, the wakeups done here will sometimes
102 * cause software-interrupt process scheduling.
103 */
104
105void
106soisconnecting(so)
107 register struct socket *so;
108{
109
110 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
111 so->so_state |= SS_ISCONNECTING;
112}
113
114void
115soisconnected(so)
116 struct socket *so;
117{
118 struct socket *head = so->so_head;
119
120 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
121 so->so_state |= SS_ISCONNECTED;
122 if (head && (so->so_state & SS_INCOMP)) {
123 if ((so->so_options & SO_ACCEPTFILTER) != 0) {
124 so->so_upcall = head->so_accf->so_accept_filter->accf_callback;
125 so->so_upcallarg = head->so_accf->so_accept_filter_arg;
126 so->so_rcv.sb_flags |= SB_UPCALL;
127 so->so_options &= ~SO_ACCEPTFILTER;
128 so->so_upcall(so, so->so_upcallarg, 0);
129 return;
130 }
131 TAILQ_REMOVE(&head->so_incomp, so, so_list);
132 head->so_incqlen--;
133 so->so_state &= ~SS_INCOMP;
134 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list);
135 head->so_qlen++;
136 so->so_state |= SS_COMP;
137 sorwakeup(head);
138 wakeup_one(&head->so_timeo);
139 } else {
140 wakeup(&so->so_timeo);
141 sorwakeup(so);
142 sowwakeup(so);
143 }
144}
145
146void
147soisdisconnecting(so)
148 register struct socket *so;
149{
150
151 so->so_state &= ~SS_ISCONNECTING;
152 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE);
153 wakeup(&so->so_timeo);
154 sowwakeup(so);
155 sorwakeup(so);
156}
157
158void
159soisdisconnected(so)
160 register struct socket *so;
161{
162
163 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
164 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED);
165 wakeup(&so->so_timeo);
166 sbdrop(&so->so_snd, so->so_snd.sb_cc);
167 sowwakeup(so);
168 sorwakeup(so);
169}
170
171/*
172 * When an attempt at a new connection is noted on a socket
173 * which accepts connections, sonewconn is called. If the
174 * connection is possible (subject to space constraints, etc.)
175 * then we allocate a new structure, propoerly linked into the
176 * data structure of the original socket, and return this.
177 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED.
178 *
179 * note: the ref count on the socket is 0 on return
180 */
181struct socket *
182sonewconn(head, connstatus)
183 register struct socket *head;
184 int connstatus;
185{
186 register struct socket *so;
187
188 if (head->so_qlen > 3 * head->so_qlimit / 2)
189 return ((struct socket *)0);
190 so = soalloc(0);
191 if (so == NULL)
192 return ((struct socket *)0);
193 if ((head->so_options & SO_ACCEPTFILTER) != 0)
194 connstatus = 0;
195 so->so_head = head;
196 so->so_type = head->so_type;
197 so->so_options = head->so_options &~ SO_ACCEPTCONN;
198 so->so_linger = head->so_linger;
199 so->so_state = head->so_state | SS_NOFDREF;
200 so->so_proto = head->so_proto;
201 so->so_timeo = head->so_timeo;
202 so->so_cred = crhold(head->so_cred);
203#ifdef MAC
204 mac_create_socket_from_socket(head, so);
205#endif
206 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat) ||
207 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) {
208 sodealloc(so);
209 return ((struct socket *)0);
210 }
211
212 if (connstatus) {
213 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list);
214 so->so_state |= SS_COMP;
215 head->so_qlen++;
216 } else {
217 if (head->so_incqlen > head->so_qlimit) {
218 struct socket *sp;
219 sp = TAILQ_FIRST(&head->so_incomp);
220 (void) soabort(sp);
221 }
222 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list);
223 so->so_state |= SS_INCOMP;
224 head->so_incqlen++;
225 }
226 if (connstatus) {
227 sorwakeup(head);
228 wakeup(&head->so_timeo);
229 so->so_state |= connstatus;
230 }
231 return (so);
232}
233
234/*
235 * Socantsendmore indicates that no more data will be sent on the
236 * socket; it would normally be applied to a socket when the user
237 * informs the system that no more data is to be sent, by the protocol
238 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data
239 * will be received, and will normally be applied to the socket by a
240 * protocol when it detects that the peer will send no more data.
241 * Data queued for reading in the socket may yet be read.
242 */
243
244void
245socantsendmore(so)
246 struct socket *so;
247{
248
249 so->so_state |= SS_CANTSENDMORE;
250 sowwakeup(so);
251}
252
253void
254socantrcvmore(so)
255 struct socket *so;
256{
257
258 so->so_state |= SS_CANTRCVMORE;
259 sorwakeup(so);
260}
261
262/*
263 * Wait for data to arrive at/drain from a socket buffer.
264 */
265int
266sbwait(sb)
267 struct sockbuf *sb;
268{
269
270 sb->sb_flags |= SB_WAIT;
271 return (tsleep(&sb->sb_cc,
272 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait",
273 sb->sb_timeo));
274}
275
276/*
277 * Lock a sockbuf already known to be locked;
278 * return any error returned from sleep (EINTR).
279 */
280int
281sb_lock(sb)
282 register struct sockbuf *sb;
283{
284 int error;
285
286 while (sb->sb_flags & SB_LOCK) {
287 sb->sb_flags |= SB_WANT;
288 error = tsleep(&sb->sb_flags,
289 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK|PCATCH,
290 "sblock", 0);
291 if (error)
292 return (error);
293 }
294 sb->sb_flags |= SB_LOCK;
295 return (0);
296}
297
298/*
299 * Wakeup processes waiting on a socket buffer.
300 * Do asynchronous notification via SIGIO
301 * if the socket has the SS_ASYNC flag set.
302 */
303void
304sowakeup(so, sb)
305 register struct socket *so;
306 register struct sockbuf *sb;
307{
308
309 selwakeup(&sb->sb_sel);
310 sb->sb_flags &= ~SB_SEL;
311 if (sb->sb_flags & SB_WAIT) {
312 sb->sb_flags &= ~SB_WAIT;
313 wakeup(&sb->sb_cc);
314 }
315 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL)
316 pgsigio(&so->so_sigio, SIGIO, 0);
317 if (sb->sb_flags & SB_UPCALL)
318 (*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT);
319 if (sb->sb_flags & SB_AIO)
320 aio_swake(so, sb);
321 KNOTE(&sb->sb_sel.si_note, 0);
322}
323
324/*
325 * Socket buffer (struct sockbuf) utility routines.
326 *
327 * Each socket contains two socket buffers: one for sending data and
328 * one for receiving data. Each buffer contains a queue of mbufs,
329 * information about the number of mbufs and amount of data in the
330 * queue, and other fields allowing select() statements and notification
331 * on data availability to be implemented.
332 *
333 * Data stored in a socket buffer is maintained as a list of records.
334 * Each record is a list of mbufs chained together with the m_next
335 * field. Records are chained together with the m_nextpkt field. The upper
336 * level routine soreceive() expects the following conventions to be
337 * observed when placing information in the receive buffer:
338 *
339 * 1. If the protocol requires each message be preceded by the sender's
340 * name, then a record containing that name must be present before
341 * any associated data (mbuf's must be of type MT_SONAME).
342 * 2. If the protocol supports the exchange of ``access rights'' (really
343 * just additional data associated with the message), and there are
344 * ``rights'' to be received, then a record containing this data
345 * should be present (mbuf's must be of type MT_RIGHTS).
346 * 3. If a name or rights record exists, then it must be followed by
347 * a data record, perhaps of zero length.
348 *
349 * Before using a new socket structure it is first necessary to reserve
350 * buffer space to the socket, by calling sbreserve(). This should commit
351 * some of the available buffer space in the system buffer pool for the
352 * socket (currently, it does nothing but enforce limits). The space
353 * should be released by calling sbrelease() when the socket is destroyed.
354 */
355
356int
357soreserve(so, sndcc, rcvcc)
358 register struct socket *so;
359 u_long sndcc, rcvcc;
360{
361 struct thread *td = curthread;
362
363 if (sbreserve(&so->so_snd, sndcc, so, td) == 0)
364 goto bad;
365 if (sbreserve(&so->so_rcv, rcvcc, so, td) == 0)
366 goto bad2;
367 if (so->so_rcv.sb_lowat == 0)
368 so->so_rcv.sb_lowat = 1;
369 if (so->so_snd.sb_lowat == 0)
370 so->so_snd.sb_lowat = MCLBYTES;
371 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
372 so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
373 return (0);
374bad2:
375 sbrelease(&so->so_snd, so);
376bad:
377 return (ENOBUFS);
378}
379
380static int
381sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS)
382{
383 int error = 0;
384 u_long old_sb_max = sb_max;
385
386 error = SYSCTL_OUT(req, arg1, sizeof(u_long));
387 if (error || !req->newptr)
388 return (error);
389 error = SYSCTL_IN(req, arg1, sizeof(u_long));
390 if (error)
391 return (error);
392 if (sb_max < MSIZE + MCLBYTES) {
393 sb_max = old_sb_max;
394 return (EINVAL);
395 }
396 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES);
397 return (0);
398}
399
400/*
401 * Allot mbufs to a sockbuf.
402 * Attempt to scale mbmax so that mbcnt doesn't become limiting
403 * if buffering efficiency is near the normal case.
404 */
405int
406sbreserve(sb, cc, so, td)
407 struct sockbuf *sb;
408 u_long cc;
409 struct socket *so;
410 struct thread *td;
411{
412
413 /*
414 * td will only be NULL when we're in an interrupt
415 * (e.g. in tcp_input())
416 */
417 if (cc > sb_max_adj)
418 return (0);
419 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc,
420 td ? td->td_proc->p_rlimit[RLIMIT_SBSIZE].rlim_cur : RLIM_INFINITY)) {
421 return (0);
422 }
423 sb->sb_mbmax = min(cc * sb_efficiency, sb_max);
424 if (sb->sb_lowat > sb->sb_hiwat)
425 sb->sb_lowat = sb->sb_hiwat;
426 return (1);
427}
428
429/*
430 * Free mbufs held by a socket, and reserved mbuf space.
431 */
432void
433sbrelease(sb, so)
434 struct sockbuf *sb;
435 struct socket *so;
436{
437
438 sbflush(sb);
439 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0,
440 RLIM_INFINITY);
441 sb->sb_mbmax = 0;
442}
443
444/*
445 * Routines to add and remove
446 * data from an mbuf queue.
447 *
448 * The routines sbappend() or sbappendrecord() are normally called to
449 * append new mbufs to a socket buffer, after checking that adequate
450 * space is available, comparing the function sbspace() with the amount
451 * of data to be added. sbappendrecord() differs from sbappend() in
452 * that data supplied is treated as the beginning of a new record.
453 * To place a sender's address, optional access rights, and data in a
454 * socket receive buffer, sbappendaddr() should be used. To place
455 * access rights and data in a socket receive buffer, sbappendrights()
456 * should be used. In either case, the new data begins a new record.
457 * Note that unlike sbappend() and sbappendrecord(), these routines check
458 * for the caller that there will be enough space to store the data.
459 * Each fails if there is not enough space, or if it cannot find mbufs
460 * to store additional information in.
461 *
462 * Reliable protocols may use the socket send buffer to hold data
463 * awaiting acknowledgement. Data is normally copied from a socket
464 * send buffer in a protocol with m_copy for output to a peer,
465 * and then removing the data from the socket buffer with sbdrop()
466 * or sbdroprecord() when the data is acknowledged by the peer.
467 */
468
469/*
470 * Append mbuf chain m to the last record in the
471 * socket buffer sb. The additional space associated
472 * the mbuf chain is recorded in sb. Empty mbufs are
473 * discarded and mbufs are compacted where possible.
474 */
475void
476sbappend(sb, m)
477 struct sockbuf *sb;
478 struct mbuf *m;
479{
480 register struct mbuf *n;
481
482 if (m == 0)
483 return;
484 n = sb->sb_mb;
485 if (n) {
486 while (n->m_nextpkt)
487 n = n->m_nextpkt;
488 do {
489 if (n->m_flags & M_EOR) {
490 sbappendrecord(sb, m); /* XXXXXX!!!! */
491 return;
492 }
493 } while (n->m_next && (n = n->m_next));
494 }
495 sbcompress(sb, m, n);
496}
497
498#ifdef SOCKBUF_DEBUG
499void
500sbcheck(sb)
501 struct sockbuf *sb;
502{
503 struct mbuf *m;
504 struct mbuf *n = 0;
505 u_long len = 0, mbcnt = 0;
506
507 for (m = sb->sb_mb; m; m = n) {
508 n = m->m_nextpkt;
509 for (; m; m = m->m_next) {
510 len += m->m_len;
511 mbcnt += MSIZE;
512 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */
513 mbcnt += m->m_ext.ext_size;
514 }
515 }
516 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) {
517 printf("cc %ld != %ld || mbcnt %ld != %ld\n", len, sb->sb_cc,
518 mbcnt, sb->sb_mbcnt);
519 panic("sbcheck");
520 }
521}
522#endif
523
524/*
525 * As above, except the mbuf chain
526 * begins a new record.
527 */
528void
529sbappendrecord(sb, m0)
530 register struct sockbuf *sb;
531 register struct mbuf *m0;
532{
533 register struct mbuf *m;
534
535 if (m0 == 0)
536 return;
537 m = sb->sb_mb;
538 if (m)
539 while (m->m_nextpkt)
540 m = m->m_nextpkt;
541 /*
542 * Put the first mbuf on the queue.
543 * Note this permits zero length records.
544 */
545 sballoc(sb, m0);
546 if (m)
547 m->m_nextpkt = m0;
548 else
549 sb->sb_mb = m0;
550 m = m0->m_next;
551 m0->m_next = 0;
552 if (m && (m0->m_flags & M_EOR)) {
553 m0->m_flags &= ~M_EOR;
554 m->m_flags |= M_EOR;
555 }
556 sbcompress(sb, m, m0);
557}
558
559/*
560 * As above except that OOB data
561 * is inserted at the beginning of the sockbuf,
562 * but after any other OOB data.
563 */
564void
565sbinsertoob(sb, m0)
566 register struct sockbuf *sb;
567 register struct mbuf *m0;
568{
569 register struct mbuf *m;
570 register struct mbuf **mp;
571
572 if (m0 == 0)
573 return;
574 for (mp = &sb->sb_mb; *mp ; mp = &((*mp)->m_nextpkt)) {
575 m = *mp;
576 again:
577 switch (m->m_type) {
578
579 case MT_OOBDATA:
580 continue; /* WANT next train */
581
582 case MT_CONTROL:
583 m = m->m_next;
584 if (m)
585 goto again; /* inspect THIS train further */
586 }
587 break;
588 }
589 /*
590 * Put the first mbuf on the queue.
591 * Note this permits zero length records.
592 */
593 sballoc(sb, m0);
594 m0->m_nextpkt = *mp;
595 *mp = m0;
596 m = m0->m_next;
597 m0->m_next = 0;
598 if (m && (m0->m_flags & M_EOR)) {
599 m0->m_flags &= ~M_EOR;
600 m->m_flags |= M_EOR;
601 }
602 sbcompress(sb, m, m0);
603}
604
605/*
606 * Append address and data, and optionally, control (ancillary) data
607 * to the receive queue of a socket. If present,
608 * m0 must include a packet header with total length.
609 * Returns 0 if no space in sockbuf or insufficient mbufs.
610 */
611int
612sbappendaddr(sb, asa, m0, control)
613 struct sockbuf *sb;
614 struct sockaddr *asa;
615 struct mbuf *m0, *control;
616{
617 struct mbuf *m, *n;
618 int space = asa->sa_len;
619
620 if (m0 && (m0->m_flags & M_PKTHDR) == 0)
621 panic("sbappendaddr");
622 if (m0)
623 space += m0->m_pkthdr.len;
624 space += m_length(control, &n);
625 if (space > sbspace(sb))
626 return (0);
627 if (asa->sa_len > MLEN)
628 return (0);
629 MGET(m, M_DONTWAIT, MT_SONAME);
630 if (m == 0)
631 return (0);
632 m->m_len = asa->sa_len;
633 bcopy(asa, mtod(m, caddr_t), asa->sa_len);
634 if (n)
635 n->m_next = m0; /* concatenate data to control */
636 else
637 control = m0;
638 m->m_next = control;
639 for (n = m; n; n = n->m_next)
640 sballoc(sb, n);
641 n = sb->sb_mb;
642 if (n) {
643 while (n->m_nextpkt)
644 n = n->m_nextpkt;
645 n->m_nextpkt = m;
646 } else
647 sb->sb_mb = m;
648 return (1);
649}
650
651int
652sbappendcontrol(sb, m0, control)
653 struct sockbuf *sb;
654 struct mbuf *control, *m0;
655{
656 struct mbuf *m, *n;
657 int space;
658
659 if (control == 0)
660 panic("sbappendcontrol");
661 space = m_length(control, &n) + m_length(m0, NULL);
662 if (space > sbspace(sb))
663 return (0);
664 n->m_next = m0; /* concatenate data to control */
665 for (m = control; m; m = m->m_next)
666 sballoc(sb, m);
667 n = sb->sb_mb;
668 if (n) {
669 while (n->m_nextpkt)
670 n = n->m_nextpkt;
671 n->m_nextpkt = control;
672 } else
673 sb->sb_mb = control;
674 return (1);
675}
676
677/*
678 * Compress mbuf chain m into the socket
679 * buffer sb following mbuf n. If n
680 * is null, the buffer is presumed empty.
681 */
682void
683sbcompress(sb, m, n)
684 register struct sockbuf *sb;
685 register struct mbuf *m, *n;
686{
687 register int eor = 0;
688 register struct mbuf *o;
689
690 while (m) {
691 eor |= m->m_flags & M_EOR;
692 if (m->m_len == 0 &&
693 (eor == 0 ||
694 (((o = m->m_next) || (o = n)) &&
695 o->m_type == m->m_type))) {
696 m = m_free(m);
697 continue;
698 }
699 if (n && (n->m_flags & M_EOR) == 0 &&
700 M_WRITABLE(n) &&
701 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */
702 m->m_len <= M_TRAILINGSPACE(n) &&
703 n->m_type == m->m_type) {
704 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len,
705 (unsigned)m->m_len);
706 n->m_len += m->m_len;
707 sb->sb_cc += m->m_len;
708 if (m->m_type != MT_DATA && m->m_type != MT_HEADER &&
709 m->m_type != MT_OOBDATA)
710 /* XXX: Probably don't need.*/
711 sb->sb_ctl += m->m_len;
712 m = m_free(m);
713 continue;
714 }
715 if (n)
716 n->m_next = m;
717 else
718 sb->sb_mb = m;
719 sballoc(sb, m);
720 n = m;
721 m->m_flags &= ~M_EOR;
722 m = m->m_next;
723 n->m_next = 0;
724 }
725 if (eor) {
726 if (n)
727 n->m_flags |= eor;
728 else
729 printf("semi-panic: sbcompress\n");
730 }
731}
732
733/*
734 * Free all mbufs in a sockbuf.
735 * Check that all resources are reclaimed.
736 */
737void
738sbflush(sb)
739 register struct sockbuf *sb;
740{
741
742 if (sb->sb_flags & SB_LOCK)
743 panic("sbflush: locked");
744 while (sb->sb_mbcnt) {
745 /*
746 * Don't call sbdrop(sb, 0) if the leading mbuf is non-empty:
747 * we would loop forever. Panic instead.
748 */
749 if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len))
750 break;
751 sbdrop(sb, (int)sb->sb_cc);
752 }
753 if (sb->sb_cc || sb->sb_mb || sb->sb_mbcnt)
754 panic("sbflush: cc %u || mb %p || mbcnt %u", sb->sb_cc, (void *)sb->sb_mb, sb->sb_mbcnt);
755}
756
757/*
758 * Drop data from (the front of) a sockbuf.
759 */
760void
761sbdrop(sb, len)
762 register struct sockbuf *sb;
763 register int len;
764{
765 register struct mbuf *m;
766 struct mbuf *next;
767
768 next = (m = sb->sb_mb) ? m->m_nextpkt : 0;
769 while (len > 0) {
770 if (m == 0) {
771 if (next == 0)
772 panic("sbdrop");
773 m = next;
774 next = m->m_nextpkt;
775 continue;
776 }
777 if (m->m_len > len) {
778 m->m_len -= len;
779 m->m_data += len;
780 sb->sb_cc -= len;
781 if (m->m_type != MT_DATA && m->m_type != MT_HEADER &&
782 m->m_type != MT_OOBDATA)
783 sb->sb_ctl -= len;
784 break;
785 }
786 len -= m->m_len;
787 sbfree(sb, m);
788 m = m_free(m);
789 }
790 while (m && m->m_len == 0) {
791 sbfree(sb, m);
792 m = m_free(m);
793 }
794 if (m) {
795 sb->sb_mb = m;
796 m->m_nextpkt = next;
797 } else
798 sb->sb_mb = next;
799}
800
801/*
802 * Drop a record off the front of a sockbuf
803 * and move the next record to the front.
804 */
805void
806sbdroprecord(sb)
807 register struct sockbuf *sb;
808{
809 register struct mbuf *m;
810
811 m = sb->sb_mb;
812 if (m) {
813 sb->sb_mb = m->m_nextpkt;
814 do {
815 sbfree(sb, m);
816 m = m_free(m);
817 } while (m);
818 }
819}
820
821/*
822 * Create a "control" mbuf containing the specified data
823 * with the specified type for presentation on a socket buffer.
824 */
825struct mbuf *
826sbcreatecontrol(p, size, type, level)
827 caddr_t p;
828 register int size;
829 int type, level;
830{
831 register struct cmsghdr *cp;
832 struct mbuf *m;
833
834 if (CMSG_SPACE((u_int)size) > MCLBYTES)
835 return ((struct mbuf *) NULL);
836 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL)
837 return ((struct mbuf *) NULL);
838 if (CMSG_SPACE((u_int)size) > MLEN) {
839 MCLGET(m, M_DONTWAIT);
840 if ((m->m_flags & M_EXT) == 0) {
841 m_free(m);
842 return ((struct mbuf *) NULL);
843 }
844 }
845 cp = mtod(m, struct cmsghdr *);
846 m->m_len = 0;
847 KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m),
848 ("sbcreatecontrol: short mbuf"));
849 if (p != NULL)
850 (void)memcpy(CMSG_DATA(cp), p, size);
851 m->m_len = CMSG_SPACE(size);
852 cp->cmsg_len = CMSG_LEN(size);
853 cp->cmsg_level = level;
854 cp->cmsg_type = type;
855 return (m);
856}
857
858/*
859 * Some routines that return EOPNOTSUPP for entry points that are not
860 * supported by a protocol. Fill in as needed.
861 */
862int
863pru_accept_notsupp(struct socket *so, struct sockaddr **nam)
864{
865 return EOPNOTSUPP;
866}
867
868int
869pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
870{
871 return EOPNOTSUPP;
872}
873
874int
875pru_connect2_notsupp(struct socket *so1, struct socket *so2)
876{
877 return EOPNOTSUPP;
878}
879
880int
881pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data,
882 struct ifnet *ifp, struct thread *td)
883{
884 return EOPNOTSUPP;
885}
886
887int
888pru_listen_notsupp(struct socket *so, struct thread *td)
889{
890 return EOPNOTSUPP;
891}
892
893int
894pru_rcvd_notsupp(struct socket *so, int flags)
895{
896 return EOPNOTSUPP;
897}
898
899int
900pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags)
901{
902 return EOPNOTSUPP;
903}
904
905/*
906 * This isn't really a ``null'' operation, but it's the default one
907 * and doesn't do anything destructive.
908 */
909int
910pru_sense_null(struct socket *so, struct stat *sb)
911{
912 sb->st_blksize = so->so_snd.sb_hiwat;
913 return 0;
914}
915
916/*
917 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
918 */
919struct sockaddr *
920dup_sockaddr(sa, canwait)
921 struct sockaddr *sa;
922 int canwait;
923{
924 struct sockaddr *sa2;
925
926 MALLOC(sa2, struct sockaddr *, sa->sa_len, M_SONAME,
927 canwait ? M_WAITOK : M_NOWAIT);
928 if (sa2)
929 bcopy(sa, sa2, sa->sa_len);
930 return sa2;
931}
932
933/*
934 * Create an external-format (``xsocket'') structure using the information
935 * in the kernel-format socket structure pointed to by so. This is done
936 * to reduce the spew of irrelevant information over this interface,
937 * to isolate user code from changes in the kernel structure, and
938 * potentially to provide information-hiding if we decide that
939 * some of this information should be hidden from users.
940 */
941void
942sotoxsocket(struct socket *so, struct xsocket *xso)
943{
944 xso->xso_len = sizeof *xso;
945 xso->xso_so = so;
946 xso->so_type = so->so_type;
947 xso->so_options = so->so_options;
948 xso->so_linger = so->so_linger;
949 xso->so_state = so->so_state;
950 xso->so_pcb = so->so_pcb;
951 xso->xso_protocol = so->so_proto->pr_protocol;
952 xso->xso_family = so->so_proto->pr_domain->dom_family;
953 xso->so_qlen = so->so_qlen;
954 xso->so_incqlen = so->so_incqlen;
955 xso->so_qlimit = so->so_qlimit;
956 xso->so_timeo = so->so_timeo;
957 xso->so_error = so->so_error;
958 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
959 xso->so_oobmark = so->so_oobmark;
960 sbtoxsockbuf(&so->so_snd, &xso->so_snd);
961 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
962 xso->so_uid = so->so_cred->cr_uid;
963}
964
965/*
966 * This does the same for sockbufs. Note that the xsockbuf structure,
967 * since it is always embedded in a socket, does not include a self
968 * pointer nor a length. We make this entry point public in case
969 * some other mechanism needs it.
970 */
971void
972sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb)
973{
974 xsb->sb_cc = sb->sb_cc;
975 xsb->sb_hiwat = sb->sb_hiwat;
976 xsb->sb_mbcnt = sb->sb_mbcnt;
977 xsb->sb_mbmax = sb->sb_mbmax;
978 xsb->sb_lowat = sb->sb_lowat;
979 xsb->sb_flags = sb->sb_flags;
980 xsb->sb_timeo = sb->sb_timeo;
981}
982
983/*
984 * Here is the definition of some of the basic objects in the kern.ipc
985 * branch of the MIB.
986 */
987SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC");
988
989/* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */
990static int dummy;
991SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, "");
992SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_ULONG|CTLFLAG_RW,
993 &sb_max, 0, sysctl_handle_sb_max, "LU", "Maximum socket buffer size");
994SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD,
995 &maxsockets, 0, "Maximum number of sockets avaliable");
996SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW,
997 &sb_efficiency, 0, "");
998
999/*
1000 * Initialise maxsockets
1001 */
1002static void init_maxsockets(void *ignored)
1003{
1004 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets);
1005 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters));
1006}
1007SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL);