uipc_sockbuf.c revision 51381
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 51381 1999-09-19 02:17:02Z green $ 35 */ 36 37#include "opt_param.h" 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/domain.h> 41#include <sys/file.h> /* for maxfiles */ 42#include <sys/kernel.h> 43#include <sys/proc.h> 44#include <sys/malloc.h> 45#include <sys/mbuf.h> 46#include <sys/protosw.h> 47#include <sys/resourcevar.h> 48#include <sys/stat.h> 49#include <sys/socket.h> 50#include <sys/socketvar.h> 51#include <sys/signalvar.h> 52#include <sys/sysctl.h> 53 54int maxsockets; 55 56/* 57 * Primitive routines for operating on sockets and socket buffers 58 */ 59 60u_long sb_max = SB_MAX; /* XXX should be static */ 61 62static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 63 64/* 65 * Procedures to manipulate state flags of socket 66 * and do appropriate wakeups. Normal sequence from the 67 * active (originating) side is that soisconnecting() is 68 * called during processing of connect() call, 69 * resulting in an eventual call to soisconnected() if/when the 70 * connection is established. When the connection is torn down 71 * soisdisconnecting() is called during processing of disconnect() call, 72 * and soisdisconnected() is called when the connection to the peer 73 * is totally severed. The semantics of these routines are such that 74 * connectionless protocols can call soisconnected() and soisdisconnected() 75 * only, bypassing the in-progress calls when setting up a ``connection'' 76 * takes no time. 77 * 78 * From the passive side, a socket is created with 79 * two queues of sockets: so_incomp for connections in progress 80 * and so_comp for connections already made and awaiting user acceptance. 81 * As a protocol is preparing incoming connections, it creates a socket 82 * structure queued on so_incomp by calling sonewconn(). When the connection 83 * is established, soisconnected() is called, and transfers the 84 * socket structure to so_comp, making it available to accept(). 85 * 86 * If a socket is closed with sockets on either 87 * so_incomp or so_comp, these sockets are dropped. 88 * 89 * If higher level protocols are implemented in 90 * the kernel, the wakeups done here will sometimes 91 * cause software-interrupt process scheduling. 92 */ 93 94void 95soisconnecting(so) 96 register struct socket *so; 97{ 98 99 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 100 so->so_state |= SS_ISCONNECTING; 101} 102 103void 104soisconnected(so) 105 register struct socket *so; 106{ 107 register struct socket *head = so->so_head; 108 109 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 110 so->so_state |= SS_ISCONNECTED; 111 if (head && (so->so_state & SS_INCOMP)) { 112 TAILQ_REMOVE(&head->so_incomp, so, so_list); 113 head->so_incqlen--; 114 so->so_state &= ~SS_INCOMP; 115 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 116 so->so_state |= SS_COMP; 117 sorwakeup(head); 118 wakeup_one(&head->so_timeo); 119 } else { 120 wakeup(&so->so_timeo); 121 sorwakeup(so); 122 sowwakeup(so); 123 } 124} 125 126void 127soisdisconnecting(so) 128 register struct socket *so; 129{ 130 131 so->so_state &= ~SS_ISCONNECTING; 132 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); 133 wakeup((caddr_t)&so->so_timeo); 134 sowwakeup(so); 135 sorwakeup(so); 136} 137 138void 139soisdisconnected(so) 140 register struct socket *so; 141{ 142 143 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 144 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED); 145 wakeup((caddr_t)&so->so_timeo); 146 sowwakeup(so); 147 sorwakeup(so); 148} 149 150/* 151 * Return a random connection that hasn't been serviced yet and 152 * is eligible for discard. There is a one in qlen chance that 153 * we will return a null, saying that there are no dropable 154 * requests. In this case, the protocol specific code should drop 155 * the new request. This insures fairness. 156 * 157 * This may be used in conjunction with protocol specific queue 158 * congestion routines. 159 */ 160struct socket * 161sodropablereq(head) 162 register struct socket *head; 163{ 164 register struct socket *so; 165 unsigned int i, j, qlen; 166 static int rnd; 167 static struct timeval old_runtime; 168 static unsigned int cur_cnt, old_cnt; 169 struct timeval tv; 170 171 getmicrouptime(&tv); 172 if ((i = (tv.tv_sec - old_runtime.tv_sec)) != 0) { 173 old_runtime = tv; 174 old_cnt = cur_cnt / i; 175 cur_cnt = 0; 176 } 177 178 so = TAILQ_FIRST(&head->so_incomp); 179 if (!so) 180 return (so); 181 182 qlen = head->so_incqlen; 183 if (++cur_cnt > qlen || old_cnt > qlen) { 184 rnd = (314159 * rnd + 66329) & 0xffff; 185 j = ((qlen + 1) * rnd) >> 16; 186 187 while (j-- && so) 188 so = TAILQ_NEXT(so, so_list); 189 } 190 191 return (so); 192} 193 194/* 195 * When an attempt at a new connection is noted on a socket 196 * which accepts connections, sonewconn is called. If the 197 * connection is possible (subject to space constraints, etc.) 198 * then we allocate a new structure, propoerly linked into the 199 * data structure of the original socket, and return this. 200 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 201 */ 202struct socket * 203sonewconn(head, connstatus) 204 register struct socket *head; 205 int connstatus; 206{ 207 208 return (sonewconn3(head, connstatus, NULL)); 209} 210 211struct socket * 212sonewconn3(head, connstatus, p) 213 register struct socket *head; 214 int connstatus; 215 struct proc *p; 216{ 217 register struct socket *so; 218 219 if (head->so_qlen > 3 * head->so_qlimit / 2) 220 return ((struct socket *)0); 221 so = soalloc(0); 222 if (so == NULL) 223 return ((struct socket *)0); 224 so->so_head = head; 225 so->so_type = head->so_type; 226 so->so_options = head->so_options &~ SO_ACCEPTCONN; 227 so->so_linger = head->so_linger; 228 so->so_state = head->so_state | SS_NOFDREF; 229 so->so_proto = head->so_proto; 230 so->so_timeo = head->so_timeo; 231 so->so_cred = p ? p->p_ucred : head->so_cred; 232 crhold(so->so_cred); 233 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat) || 234 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { 235 sodealloc(so); 236 return ((struct socket *)0); 237 } 238 239 if (connstatus) { 240 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 241 so->so_state |= SS_COMP; 242 } else { 243 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 244 so->so_state |= SS_INCOMP; 245 head->so_incqlen++; 246 } 247 head->so_qlen++; 248 if (connstatus) { 249 sorwakeup(head); 250 wakeup((caddr_t)&head->so_timeo); 251 so->so_state |= connstatus; 252 } 253 return (so); 254} 255 256/* 257 * Socantsendmore indicates that no more data will be sent on the 258 * socket; it would normally be applied to a socket when the user 259 * informs the system that no more data is to be sent, by the protocol 260 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 261 * will be received, and will normally be applied to the socket by a 262 * protocol when it detects that the peer will send no more data. 263 * Data queued for reading in the socket may yet be read. 264 */ 265 266void 267socantsendmore(so) 268 struct socket *so; 269{ 270 271 so->so_state |= SS_CANTSENDMORE; 272 sowwakeup(so); 273} 274 275void 276socantrcvmore(so) 277 struct socket *so; 278{ 279 280 so->so_state |= SS_CANTRCVMORE; 281 sorwakeup(so); 282} 283 284/* 285 * Wait for data to arrive at/drain from a socket buffer. 286 */ 287int 288sbwait(sb) 289 struct sockbuf *sb; 290{ 291 292 sb->sb_flags |= SB_WAIT; 293 return (tsleep((caddr_t)&sb->sb_cc, 294 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait", 295 sb->sb_timeo)); 296} 297 298/* 299 * Lock a sockbuf already known to be locked; 300 * return any error returned from sleep (EINTR). 301 */ 302int 303sb_lock(sb) 304 register struct sockbuf *sb; 305{ 306 int error; 307 308 while (sb->sb_flags & SB_LOCK) { 309 sb->sb_flags |= SB_WANT; 310 error = tsleep((caddr_t)&sb->sb_flags, 311 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK|PCATCH, 312 "sblock", 0); 313 if (error) 314 return (error); 315 } 316 sb->sb_flags |= SB_LOCK; 317 return (0); 318} 319 320/* 321 * Wakeup processes waiting on a socket buffer. 322 * Do asynchronous notification via SIGIO 323 * if the socket has the SS_ASYNC flag set. 324 */ 325void 326sowakeup(so, sb) 327 register struct socket *so; 328 register struct sockbuf *sb; 329{ 330 selwakeup(&sb->sb_sel); 331 sb->sb_flags &= ~SB_SEL; 332 if (sb->sb_flags & SB_WAIT) { 333 sb->sb_flags &= ~SB_WAIT; 334 wakeup((caddr_t)&sb->sb_cc); 335 } 336 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 337 pgsigio(so->so_sigio, SIGIO, 0); 338 if (sb->sb_flags & SB_UPCALL) 339 (*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT); 340} 341 342/* 343 * Socket buffer (struct sockbuf) utility routines. 344 * 345 * Each socket contains two socket buffers: one for sending data and 346 * one for receiving data. Each buffer contains a queue of mbufs, 347 * information about the number of mbufs and amount of data in the 348 * queue, and other fields allowing select() statements and notification 349 * on data availability to be implemented. 350 * 351 * Data stored in a socket buffer is maintained as a list of records. 352 * Each record is a list of mbufs chained together with the m_next 353 * field. Records are chained together with the m_nextpkt field. The upper 354 * level routine soreceive() expects the following conventions to be 355 * observed when placing information in the receive buffer: 356 * 357 * 1. If the protocol requires each message be preceded by the sender's 358 * name, then a record containing that name must be present before 359 * any associated data (mbuf's must be of type MT_SONAME). 360 * 2. If the protocol supports the exchange of ``access rights'' (really 361 * just additional data associated with the message), and there are 362 * ``rights'' to be received, then a record containing this data 363 * should be present (mbuf's must be of type MT_RIGHTS). 364 * 3. If a name or rights record exists, then it must be followed by 365 * a data record, perhaps of zero length. 366 * 367 * Before using a new socket structure it is first necessary to reserve 368 * buffer space to the socket, by calling sbreserve(). This should commit 369 * some of the available buffer space in the system buffer pool for the 370 * socket (currently, it does nothing but enforce limits). The space 371 * should be released by calling sbrelease() when the socket is destroyed. 372 */ 373 374int 375soreserve(so, sndcc, rcvcc) 376 register struct socket *so; 377 u_long sndcc, rcvcc; 378{ 379 380 if (sbreserve(&so->so_snd, sndcc) == 0) 381 goto bad; 382 if (sbreserve(&so->so_rcv, rcvcc) == 0) 383 goto bad2; 384 if (so->so_rcv.sb_lowat == 0) 385 so->so_rcv.sb_lowat = 1; 386 if (so->so_snd.sb_lowat == 0) 387 so->so_snd.sb_lowat = MCLBYTES; 388 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 389 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 390 return (0); 391bad2: 392 sbrelease(&so->so_snd); 393bad: 394 return (ENOBUFS); 395} 396 397/* 398 * Allot mbufs to a sockbuf. 399 * Attempt to scale mbmax so that mbcnt doesn't become limiting 400 * if buffering efficiency is near the normal case. 401 */ 402int 403sbreserve(sb, cc) 404 struct sockbuf *sb; 405 u_long cc; 406{ 407 if ((u_quad_t)cc > (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES)) 408 return (0); 409 sb->sb_hiwat = cc; 410 sb->sb_mbmax = min(cc * sb_efficiency, sb_max); 411 if (sb->sb_lowat > sb->sb_hiwat) 412 sb->sb_lowat = sb->sb_hiwat; 413 return (1); 414} 415 416/* 417 * Free mbufs held by a socket, and reserved mbuf space. 418 */ 419void 420sbrelease(sb) 421 struct sockbuf *sb; 422{ 423 424 sbflush(sb); 425 sb->sb_hiwat = sb->sb_mbmax = 0; 426} 427 428/* 429 * Routines to add and remove 430 * data from an mbuf queue. 431 * 432 * The routines sbappend() or sbappendrecord() are normally called to 433 * append new mbufs to a socket buffer, after checking that adequate 434 * space is available, comparing the function sbspace() with the amount 435 * of data to be added. sbappendrecord() differs from sbappend() in 436 * that data supplied is treated as the beginning of a new record. 437 * To place a sender's address, optional access rights, and data in a 438 * socket receive buffer, sbappendaddr() should be used. To place 439 * access rights and data in a socket receive buffer, sbappendrights() 440 * should be used. In either case, the new data begins a new record. 441 * Note that unlike sbappend() and sbappendrecord(), these routines check 442 * for the caller that there will be enough space to store the data. 443 * Each fails if there is not enough space, or if it cannot find mbufs 444 * to store additional information in. 445 * 446 * Reliable protocols may use the socket send buffer to hold data 447 * awaiting acknowledgement. Data is normally copied from a socket 448 * send buffer in a protocol with m_copy for output to a peer, 449 * and then removing the data from the socket buffer with sbdrop() 450 * or sbdroprecord() when the data is acknowledged by the peer. 451 */ 452 453/* 454 * Append mbuf chain m to the last record in the 455 * socket buffer sb. The additional space associated 456 * the mbuf chain is recorded in sb. Empty mbufs are 457 * discarded and mbufs are compacted where possible. 458 */ 459void 460sbappend(sb, m) 461 struct sockbuf *sb; 462 struct mbuf *m; 463{ 464 register struct mbuf *n; 465 466 if (m == 0) 467 return; 468 n = sb->sb_mb; 469 if (n) { 470 while (n->m_nextpkt) 471 n = n->m_nextpkt; 472 do { 473 if (n->m_flags & M_EOR) { 474 sbappendrecord(sb, m); /* XXXXXX!!!! */ 475 return; 476 } 477 } while (n->m_next && (n = n->m_next)); 478 } 479 sbcompress(sb, m, n); 480} 481 482#ifdef SOCKBUF_DEBUG 483void 484sbcheck(sb) 485 register struct sockbuf *sb; 486{ 487 register struct mbuf *m; 488 register struct mbuf *n = 0; 489 register u_long len = 0, mbcnt = 0; 490 491 for (m = sb->sb_mb; m; m = n) { 492 n = m->m_nextpkt; 493 for (; m; m = m->m_next) { 494 len += m->m_len; 495 mbcnt += MSIZE; 496 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 497 mbcnt += m->m_ext.ext_size; 498 } 499 } 500 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 501 printf("cc %ld != %ld || mbcnt %ld != %ld\n", len, sb->sb_cc, 502 mbcnt, sb->sb_mbcnt); 503 panic("sbcheck"); 504 } 505} 506#endif 507 508/* 509 * As above, except the mbuf chain 510 * begins a new record. 511 */ 512void 513sbappendrecord(sb, m0) 514 register struct sockbuf *sb; 515 register struct mbuf *m0; 516{ 517 register struct mbuf *m; 518 519 if (m0 == 0) 520 return; 521 m = sb->sb_mb; 522 if (m) 523 while (m->m_nextpkt) 524 m = m->m_nextpkt; 525 /* 526 * Put the first mbuf on the queue. 527 * Note this permits zero length records. 528 */ 529 sballoc(sb, m0); 530 if (m) 531 m->m_nextpkt = m0; 532 else 533 sb->sb_mb = m0; 534 m = m0->m_next; 535 m0->m_next = 0; 536 if (m && (m0->m_flags & M_EOR)) { 537 m0->m_flags &= ~M_EOR; 538 m->m_flags |= M_EOR; 539 } 540 sbcompress(sb, m, m0); 541} 542 543/* 544 * As above except that OOB data 545 * is inserted at the beginning of the sockbuf, 546 * but after any other OOB data. 547 */ 548void 549sbinsertoob(sb, m0) 550 register struct sockbuf *sb; 551 register struct mbuf *m0; 552{ 553 register struct mbuf *m; 554 register struct mbuf **mp; 555 556 if (m0 == 0) 557 return; 558 for (mp = &sb->sb_mb; *mp ; mp = &((*mp)->m_nextpkt)) { 559 m = *mp; 560 again: 561 switch (m->m_type) { 562 563 case MT_OOBDATA: 564 continue; /* WANT next train */ 565 566 case MT_CONTROL: 567 m = m->m_next; 568 if (m) 569 goto again; /* inspect THIS train further */ 570 } 571 break; 572 } 573 /* 574 * Put the first mbuf on the queue. 575 * Note this permits zero length records. 576 */ 577 sballoc(sb, m0); 578 m0->m_nextpkt = *mp; 579 *mp = m0; 580 m = m0->m_next; 581 m0->m_next = 0; 582 if (m && (m0->m_flags & M_EOR)) { 583 m0->m_flags &= ~M_EOR; 584 m->m_flags |= M_EOR; 585 } 586 sbcompress(sb, m, m0); 587} 588 589/* 590 * Append address and data, and optionally, control (ancillary) data 591 * to the receive queue of a socket. If present, 592 * m0 must include a packet header with total length. 593 * Returns 0 if no space in sockbuf or insufficient mbufs. 594 */ 595int 596sbappendaddr(sb, asa, m0, control) 597 register struct sockbuf *sb; 598 struct sockaddr *asa; 599 struct mbuf *m0, *control; 600{ 601 register struct mbuf *m, *n; 602 int space = asa->sa_len; 603 604if (m0 && (m0->m_flags & M_PKTHDR) == 0) 605panic("sbappendaddr"); 606 if (m0) 607 space += m0->m_pkthdr.len; 608 for (n = control; n; n = n->m_next) { 609 space += n->m_len; 610 if (n->m_next == 0) /* keep pointer to last control buf */ 611 break; 612 } 613 if (space > sbspace(sb)) 614 return (0); 615 if (asa->sa_len > MLEN) 616 return (0); 617 MGET(m, M_DONTWAIT, MT_SONAME); 618 if (m == 0) 619 return (0); 620 m->m_len = asa->sa_len; 621 bcopy((caddr_t)asa, mtod(m, caddr_t), asa->sa_len); 622 if (n) 623 n->m_next = m0; /* concatenate data to control */ 624 else 625 control = m0; 626 m->m_next = control; 627 for (n = m; n; n = n->m_next) 628 sballoc(sb, n); 629 n = sb->sb_mb; 630 if (n) { 631 while (n->m_nextpkt) 632 n = n->m_nextpkt; 633 n->m_nextpkt = m; 634 } else 635 sb->sb_mb = m; 636 return (1); 637} 638 639int 640sbappendcontrol(sb, m0, control) 641 struct sockbuf *sb; 642 struct mbuf *control, *m0; 643{ 644 register struct mbuf *m, *n; 645 int space = 0; 646 647 if (control == 0) 648 panic("sbappendcontrol"); 649 for (m = control; ; m = m->m_next) { 650 space += m->m_len; 651 if (m->m_next == 0) 652 break; 653 } 654 n = m; /* save pointer to last control buffer */ 655 for (m = m0; m; m = m->m_next) 656 space += m->m_len; 657 if (space > sbspace(sb)) 658 return (0); 659 n->m_next = m0; /* concatenate data to control */ 660 for (m = control; m; m = m->m_next) 661 sballoc(sb, m); 662 n = sb->sb_mb; 663 if (n) { 664 while (n->m_nextpkt) 665 n = n->m_nextpkt; 666 n->m_nextpkt = control; 667 } else 668 sb->sb_mb = control; 669 return (1); 670} 671 672/* 673 * Compress mbuf chain m into the socket 674 * buffer sb following mbuf n. If n 675 * is null, the buffer is presumed empty. 676 */ 677void 678sbcompress(sb, m, n) 679 register struct sockbuf *sb; 680 register struct mbuf *m, *n; 681{ 682 register int eor = 0; 683 register struct mbuf *o; 684 685 while (m) { 686 eor |= m->m_flags & M_EOR; 687 if (m->m_len == 0 && 688 (eor == 0 || 689 (((o = m->m_next) || (o = n)) && 690 o->m_type == m->m_type))) { 691 m = m_free(m); 692 continue; 693 } 694 if (n && (n->m_flags & (M_EXT | M_EOR)) == 0 && 695 (n->m_data + n->m_len + m->m_len) < &n->m_dat[MLEN] && 696 n->m_type == m->m_type) { 697 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, 698 (unsigned)m->m_len); 699 n->m_len += m->m_len; 700 sb->sb_cc += m->m_len; 701 m = m_free(m); 702 continue; 703 } 704 if (n) 705 n->m_next = m; 706 else 707 sb->sb_mb = m; 708 sballoc(sb, m); 709 n = m; 710 m->m_flags &= ~M_EOR; 711 m = m->m_next; 712 n->m_next = 0; 713 } 714 if (eor) { 715 if (n) 716 n->m_flags |= eor; 717 else 718 printf("semi-panic: sbcompress\n"); 719 } 720} 721 722/* 723 * Free all mbufs in a sockbuf. 724 * Check that all resources are reclaimed. 725 */ 726void 727sbflush(sb) 728 register struct sockbuf *sb; 729{ 730 731 if (sb->sb_flags & SB_LOCK) 732 panic("sbflush: locked"); 733 while (sb->sb_mbcnt && sb->sb_cc) 734 sbdrop(sb, (int)sb->sb_cc); 735 if (sb->sb_cc || sb->sb_mb || sb->sb_mbcnt) 736 panic("sbflush: cc %ld || mb %p || mbcnt %ld", sb->sb_cc, (void *)sb->sb_mb, sb->sb_mbcnt); 737} 738 739/* 740 * Drop data from (the front of) a sockbuf. 741 */ 742void 743sbdrop(sb, len) 744 register struct sockbuf *sb; 745 register int len; 746{ 747 register struct mbuf *m, *mn; 748 struct mbuf *next; 749 750 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 751 while (len > 0) { 752 if (m == 0) { 753 if (next == 0) 754 panic("sbdrop"); 755 m = next; 756 next = m->m_nextpkt; 757 continue; 758 } 759 if (m->m_len > len) { 760 m->m_len -= len; 761 m->m_data += len; 762 sb->sb_cc -= len; 763 break; 764 } 765 len -= m->m_len; 766 sbfree(sb, m); 767 MFREE(m, mn); 768 m = mn; 769 } 770 while (m && m->m_len == 0) { 771 sbfree(sb, m); 772 MFREE(m, mn); 773 m = mn; 774 } 775 if (m) { 776 sb->sb_mb = m; 777 m->m_nextpkt = next; 778 } else 779 sb->sb_mb = next; 780} 781 782/* 783 * Drop a record off the front of a sockbuf 784 * and move the next record to the front. 785 */ 786void 787sbdroprecord(sb) 788 register struct sockbuf *sb; 789{ 790 register struct mbuf *m, *mn; 791 792 m = sb->sb_mb; 793 if (m) { 794 sb->sb_mb = m->m_nextpkt; 795 do { 796 sbfree(sb, m); 797 MFREE(m, mn); 798 m = mn; 799 } while (m); 800 } 801} 802 803/* 804 * Create a "control" mbuf containing the specified data 805 * with the specified type for presentation on a socket buffer. 806 */ 807struct mbuf * 808sbcreatecontrol(p, size, type, level) 809 caddr_t p; 810 register int size; 811 int type, level; 812{ 813 register struct cmsghdr *cp; 814 struct mbuf *m; 815 816 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 817 return ((struct mbuf *) NULL); 818 cp = mtod(m, struct cmsghdr *); 819 /* XXX check size? */ 820 (void)memcpy(CMSG_DATA(cp), p, size); 821 size += sizeof(*cp); 822 m->m_len = size; 823 cp->cmsg_len = size; 824 cp->cmsg_level = level; 825 cp->cmsg_type = type; 826 return (m); 827} 828 829/* 830 * Some routines that return EOPNOTSUPP for entry points that are not 831 * supported by a protocol. Fill in as needed. 832 */ 833int 834pru_accept_notsupp(struct socket *so, struct sockaddr **nam) 835{ 836 return EOPNOTSUPP; 837} 838 839int 840pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct proc *p) 841{ 842 return EOPNOTSUPP; 843} 844 845int 846pru_connect2_notsupp(struct socket *so1, struct socket *so2) 847{ 848 return EOPNOTSUPP; 849} 850 851int 852pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, 853 struct ifnet *ifp, struct proc *p) 854{ 855 return EOPNOTSUPP; 856} 857 858int 859pru_listen_notsupp(struct socket *so, struct proc *p) 860{ 861 return EOPNOTSUPP; 862} 863 864int 865pru_rcvd_notsupp(struct socket *so, int flags) 866{ 867 return EOPNOTSUPP; 868} 869 870int 871pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 872{ 873 return EOPNOTSUPP; 874} 875 876/* 877 * This isn't really a ``null'' operation, but it's the default one 878 * and doesn't do anything destructive. 879 */ 880int 881pru_sense_null(struct socket *so, struct stat *sb) 882{ 883 sb->st_blksize = so->so_snd.sb_hiwat; 884 return 0; 885} 886 887/* 888 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. 889 */ 890struct sockaddr * 891dup_sockaddr(sa, canwait) 892 struct sockaddr *sa; 893 int canwait; 894{ 895 struct sockaddr *sa2; 896 897 MALLOC(sa2, struct sockaddr *, sa->sa_len, M_SONAME, 898 canwait ? M_WAITOK : M_NOWAIT); 899 if (sa2) 900 bcopy(sa, sa2, sa->sa_len); 901 return sa2; 902} 903 904/* 905 * Create an external-format (``xsocket'') structure using the information 906 * in the kernel-format socket structure pointed to by so. This is done 907 * to reduce the spew of irrelevant information over this interface, 908 * to isolate user code from changes in the kernel structure, and 909 * potentially to provide information-hiding if we decide that 910 * some of this information should be hidden from users. 911 */ 912void 913sotoxsocket(struct socket *so, struct xsocket *xso) 914{ 915 xso->xso_len = sizeof *xso; 916 xso->xso_so = so; 917 xso->so_type = so->so_type; 918 xso->so_options = so->so_options; 919 xso->so_linger = so->so_linger; 920 xso->so_state = so->so_state; 921 xso->so_pcb = so->so_pcb; 922 xso->xso_protocol = so->so_proto->pr_protocol; 923 xso->xso_family = so->so_proto->pr_domain->dom_family; 924 xso->so_qlen = so->so_qlen; 925 xso->so_incqlen = so->so_incqlen; 926 xso->so_qlimit = so->so_qlimit; 927 xso->so_timeo = so->so_timeo; 928 xso->so_error = so->so_error; 929 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 930 xso->so_oobmark = so->so_oobmark; 931 sbtoxsockbuf(&so->so_snd, &xso->so_snd); 932 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 933 xso->so_uid = so->so_cred->cr_uid; 934} 935 936/* 937 * This does the same for sockbufs. Note that the xsockbuf structure, 938 * since it is always embedded in a socket, does not include a self 939 * pointer nor a length. We make this entry point public in case 940 * some other mechanism needs it. 941 */ 942void 943sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 944{ 945 xsb->sb_cc = sb->sb_cc; 946 xsb->sb_hiwat = sb->sb_hiwat; 947 xsb->sb_mbcnt = sb->sb_mbcnt; 948 xsb->sb_mbmax = sb->sb_mbmax; 949 xsb->sb_lowat = sb->sb_lowat; 950 xsb->sb_flags = sb->sb_flags; 951 xsb->sb_timeo = sb->sb_timeo; 952} 953 954/* 955 * Here is the definition of some of the basic objects in the kern.ipc 956 * branch of the MIB. 957 */ 958SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 959 960/* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 961static int dummy; 962SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 963 964SYSCTL_INT(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLFLAG_RW, 965 &sb_max, 0, "Maximum socket buffer size"); 966SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 967 &maxsockets, 0, "Maximum number of sockets avaliable"); 968SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 969 &sb_efficiency, 0, ""); 970 971/* 972 * Initialise maxsockets 973 */ 974static void init_maxsockets(void *ignored) 975{ 976 TUNABLE_INT_FETCH("kern.ipc.maxsockets", 0, maxsockets); 977 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 978} 979SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 980