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 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include "opt_mac.h" 40 #include "opt_param.h" 41 42 #include <sys/param.h> 43 #include <sys/aio.h> /* for aio_swake proto */ 44 #include <sys/domain.h> 45 #include <sys/event.h> 46 #include <sys/file.h> /* for maxfiles */ 47 #include <sys/kernel.h> 48 #include <sys/lock.h> 49 #include <sys/mac.h> 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/mutex.h> 53 #include <sys/proc.h> 54 #include <sys/protosw.h> 55 #include <sys/resourcevar.h> 56 #include <sys/signalvar.h> 57 #include <sys/socket.h> 58 #include <sys/socketvar.h> 59 #include <sys/stat.h> 60 #include <sys/sysctl.h> 61 #include <sys/systm.h> 62 63 int maxsockets; 64 65 void (*aio_swake)(struct socket *, struct sockbuf *); 66 67 /* 68 * Primitive routines for operating on sockets and socket buffers 69 */ 70 71 u_long sb_max = SB_MAX; 72 static u_long sb_max_adj = 73 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */ 74 75 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 76 77 /* 78 * Procedures to manipulate state flags of socket 79 * and do appropriate wakeups. Normal sequence from the 80 * active (originating) side is that soisconnecting() is 81 * called during processing of connect() call, 82 * resulting in an eventual call to soisconnected() if/when the 83 * connection is established. When the connection is torn down 84 * soisdisconnecting() is called during processing of disconnect() call, 85 * and soisdisconnected() is called when the connection to the peer 86 * is totally severed. The semantics of these routines are such that 87 * connectionless protocols can call soisconnected() and soisdisconnected() 88 * only, bypassing the in-progress calls when setting up a ``connection'' 89 * takes no time. 90 * 91 * From the passive side, a socket is created with 92 * two queues of sockets: so_incomp for connections in progress 93 * and so_comp for connections already made and awaiting user acceptance. 94 * As a protocol is preparing incoming connections, it creates a socket 95 * structure queued on so_incomp by calling sonewconn(). When the connection 96 * is established, soisconnected() is called, and transfers the 97 * socket structure to so_comp, making it available to accept(). 98 * 99 * If a socket is closed with sockets on either 100 * so_incomp or so_comp, these sockets are dropped. 101 * 102 * If higher level protocols are implemented in 103 * the kernel, the wakeups done here will sometimes 104 * cause software-interrupt process scheduling. 105 */ 106 107 void 108 soisconnecting(so) 109 register struct socket *so; 110 { 111 112 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 113 so->so_state |= SS_ISCONNECTING; 114 } 115 116 void 117 soisconnected(so) 118 struct socket *so; 119 { 120 struct socket *head = so->so_head; 121 122 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 123 so->so_state |= SS_ISCONNECTED; 124 if (head && (so->so_state & SS_INCOMP)) { 125 if ((so->so_options & SO_ACCEPTFILTER) != 0) { 126 so->so_upcall = head->so_accf->so_accept_filter->accf_callback; 127 so->so_upcallarg = head->so_accf->so_accept_filter_arg; 128 so->so_rcv.sb_flags |= SB_UPCALL; 129 so->so_options &= ~SO_ACCEPTFILTER; 130 so->so_upcall(so, so->so_upcallarg, M_TRYWAIT); 131 return; 132 } 133 TAILQ_REMOVE(&head->so_incomp, so, so_list); 134 head->so_incqlen--; 135 so->so_state &= ~SS_INCOMP; 136 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 137 head->so_qlen++; 138 so->so_state |= SS_COMP; 139 sorwakeup(head); 140 wakeup_one(&head->so_timeo); 141 } else { 142 wakeup(&so->so_timeo); 143 sorwakeup(so); 144 sowwakeup(so); 145 } 146 } 147 148 void 149 soisdisconnecting(so) 150 register struct socket *so; 151 { 152 153 so->so_state &= ~SS_ISCONNECTING; 154 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); 155 wakeup(&so->so_timeo); 156 sowwakeup(so); 157 sorwakeup(so); 158 } 159 160 void 161 soisdisconnected(so) 162 register struct socket *so; 163 { 164 165 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 166 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED); 167 wakeup(&so->so_timeo); 168 sbdrop(&so->so_snd, so->so_snd.sb_cc); 169 sowwakeup(so); 170 sorwakeup(so); 171 } 172 173 /* 174 * When an attempt at a new connection is noted on a socket 175 * which accepts connections, sonewconn is called. If the 176 * connection is possible (subject to space constraints, etc.) 177 * then we allocate a new structure, propoerly linked into the 178 * data structure of the original socket, and return this. 179 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 180 * 181 * note: the ref count on the socket is 0 on return 182 */ 183 struct socket * 184 sonewconn(head, connstatus) 185 register struct socket *head; 186 int connstatus; 187 { 188 register struct socket *so; 189 190 if (head->so_qlen > 3 * head->so_qlimit / 2) 191 return ((struct socket *)0); 192 so = soalloc(0); 193 if (so == NULL) 194 return ((struct socket *)0); 195 if ((head->so_options & SO_ACCEPTFILTER) != 0) 196 connstatus = 0; 197 so->so_head = head; 198 so->so_type = head->so_type; 199 so->so_options = head->so_options &~ SO_ACCEPTCONN; 200 so->so_linger = head->so_linger; 201 so->so_state = head->so_state | SS_NOFDREF; 202 so->so_proto = head->so_proto; 203 so->so_timeo = head->so_timeo; 204 so->so_cred = crhold(head->so_cred); 205 #ifdef MAC 206 mac_create_socket_from_socket(head, so); 207 #endif 208 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat) || 209 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { 210 sodealloc(so); 211 return ((struct socket *)0); 212 } 213 214 if (connstatus) { 215 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 216 so->so_state |= SS_COMP; 217 head->so_qlen++; 218 } else { 219 if (head->so_incqlen > head->so_qlimit) { 220 struct socket *sp; 221 sp = TAILQ_FIRST(&head->so_incomp); 222 (void) soabort(sp); 223 } 224 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 225 so->so_state |= SS_INCOMP; 226 head->so_incqlen++; 227 } 228 if (connstatus) { 229 sorwakeup(head); 230 wakeup(&head->so_timeo); 231 so->so_state |= connstatus; 232 } 233 return (so); 234 } 235 236 /* 237 * Socantsendmore indicates that no more data will be sent on the 238 * socket; it would normally be applied to a socket when the user 239 * informs the system that no more data is to be sent, by the protocol 240 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 241 * will be received, and will normally be applied to the socket by a 242 * protocol when it detects that the peer will send no more data. 243 * Data queued for reading in the socket may yet be read. 244 */ 245 246 void 247 socantsendmore(so) 248 struct socket *so; 249 { 250 251 so->so_state |= SS_CANTSENDMORE; 252 sowwakeup(so); 253 } 254 255 void 256 socantrcvmore(so) 257 struct socket *so; 258 { 259 260 so->so_state |= SS_CANTRCVMORE; 261 sorwakeup(so); 262 } 263 264 /* 265 * Wait for data to arrive at/drain from a socket buffer. 266 */ 267 int 268 sbwait(sb) 269 struct sockbuf *sb; 270 { 271 272 sb->sb_flags |= SB_WAIT; 273 return (tsleep(&sb->sb_cc, 274 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait", 275 sb->sb_timeo)); 276 } 277 278 /* 279 * Lock a sockbuf already known to be locked; 280 * return any error returned from sleep (EINTR). 281 */ 282 int 283 sb_lock(sb) 284 register struct sockbuf *sb; 285 { 286 int error; 287 288 while (sb->sb_flags & SB_LOCK) { 289 sb->sb_flags |= SB_WANT; 290 error = tsleep(&sb->sb_flags, 291 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK|PCATCH, 292 "sblock", 0); 293 if (error) 294 return (error); 295 } 296 sb->sb_flags |= SB_LOCK; 297 return (0); 298 } 299 300 /* 301 * Wakeup processes waiting on a socket buffer. 302 * Do asynchronous notification via SIGIO 303 * if the socket has the SS_ASYNC flag set. 304 */ 305 void 306 sowakeup(so, sb) 307 register struct socket *so; 308 register struct sockbuf *sb; 309 { 310 311 selwakeup(&sb->sb_sel); 312 sb->sb_flags &= ~SB_SEL; 313 if (sb->sb_flags & SB_WAIT) { 314 sb->sb_flags &= ~SB_WAIT; 315 wakeup(&sb->sb_cc); 316 } 317 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 318 pgsigio(&so->so_sigio, SIGIO, 0); 319 if (sb->sb_flags & SB_UPCALL) 320 (*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT); 321 if (sb->sb_flags & SB_AIO) 322 aio_swake(so, sb); 323 KNOTE(&sb->sb_sel.si_note, 0); 324 } 325 326 /* 327 * Socket buffer (struct sockbuf) utility routines. 328 * 329 * Each socket contains two socket buffers: one for sending data and 330 * one for receiving data. Each buffer contains a queue of mbufs, 331 * information about the number of mbufs and amount of data in the 332 * queue, and other fields allowing select() statements and notification 333 * on data availability to be implemented. 334 * 335 * Data stored in a socket buffer is maintained as a list of records. 336 * Each record is a list of mbufs chained together with the m_next 337 * field. Records are chained together with the m_nextpkt field. The upper 338 * level routine soreceive() expects the following conventions to be 339 * observed when placing information in the receive buffer: 340 * 341 * 1. If the protocol requires each message be preceded by the sender's 342 * name, then a record containing that name must be present before 343 * any associated data (mbuf's must be of type MT_SONAME). 344 * 2. If the protocol supports the exchange of ``access rights'' (really 345 * just additional data associated with the message), and there are 346 * ``rights'' to be received, then a record containing this data 347 * should be present (mbuf's must be of type MT_RIGHTS). 348 * 3. If a name or rights record exists, then it must be followed by 349 * a data record, perhaps of zero length. 350 * 351 * Before using a new socket structure it is first necessary to reserve 352 * buffer space to the socket, by calling sbreserve(). This should commit 353 * some of the available buffer space in the system buffer pool for the 354 * socket (currently, it does nothing but enforce limits). The space 355 * should be released by calling sbrelease() when the socket is destroyed. 356 */ 357 358 int 359 soreserve(so, sndcc, rcvcc) 360 register struct socket *so; 361 u_long sndcc, rcvcc; 362 { 363 struct thread *td = curthread; 364 365 if (sbreserve(&so->so_snd, sndcc, so, td) == 0) 366 goto bad; 367 if (sbreserve(&so->so_rcv, rcvcc, so, td) == 0) 368 goto bad2; 369 if (so->so_rcv.sb_lowat == 0) 370 so->so_rcv.sb_lowat = 1; 371 if (so->so_snd.sb_lowat == 0) 372 so->so_snd.sb_lowat = MCLBYTES; 373 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 374 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 375 return (0); 376 bad2: 377 sbrelease(&so->so_snd, so); 378 bad: 379 return (ENOBUFS); 380 } 381 382 static int 383 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 384 { 385 int error = 0; 386 u_long old_sb_max = sb_max; 387 388 error = SYSCTL_OUT(req, arg1, sizeof(u_long)); 389 if (error || !req->newptr) 390 return (error); 391 error = SYSCTL_IN(req, arg1, sizeof(u_long)); 392 if (error) 393 return (error); 394 if (sb_max < MSIZE + MCLBYTES) { 395 sb_max = old_sb_max; 396 return (EINVAL); 397 } 398 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 399 return (0); 400 } 401 402 /* 403 * Allot mbufs to a sockbuf. 404 * Attempt to scale mbmax so that mbcnt doesn't become limiting 405 * if buffering efficiency is near the normal case. 406 */ 407 int 408 sbreserve(sb, cc, so, td) 409 struct sockbuf *sb; 410 u_long cc; 411 struct socket *so; 412 struct thread *td; 413 { 414 415 /* 416 * td will only be NULL when we're in an interrupt 417 * (e.g. in tcp_input()) 418 */ 419 if (cc > sb_max_adj) 420 return (0); 421 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 422 td ? td->td_proc->p_rlimit[RLIMIT_SBSIZE].rlim_cur : RLIM_INFINITY)) { 423 return (0); 424 } 425 sb->sb_mbmax = min(cc * sb_efficiency, sb_max); 426 if (sb->sb_lowat > sb->sb_hiwat) 427 sb->sb_lowat = sb->sb_hiwat; 428 return (1); 429 } 430 431 /* 432 * Free mbufs held by a socket, and reserved mbuf space. 433 */ 434 void 435 sbrelease(sb, so) 436 struct sockbuf *sb; 437 struct socket *so; 438 { 439 440 sbflush(sb); 441 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0, 442 RLIM_INFINITY); 443 sb->sb_mbmax = 0; 444 } 445 446 /* 447 * Routines to add and remove 448 * data from an mbuf queue. 449 * 450 * The routines sbappend() or sbappendrecord() are normally called to 451 * append new mbufs to a socket buffer, after checking that adequate 452 * space is available, comparing the function sbspace() with the amount 453 * of data to be added. sbappendrecord() differs from sbappend() in 454 * that data supplied is treated as the beginning of a new record. 455 * To place a sender's address, optional access rights, and data in a 456 * socket receive buffer, sbappendaddr() should be used. To place 457 * access rights and data in a socket receive buffer, sbappendrights() 458 * should be used. In either case, the new data begins a new record. 459 * Note that unlike sbappend() and sbappendrecord(), these routines check 460 * for the caller that there will be enough space to store the data. 461 * Each fails if there is not enough space, or if it cannot find mbufs 462 * to store additional information in. 463 * 464 * Reliable protocols may use the socket send buffer to hold data 465 * awaiting acknowledgement. Data is normally copied from a socket 466 * send buffer in a protocol with m_copy for output to a peer, 467 * and then removing the data from the socket buffer with sbdrop() 468 * or sbdroprecord() when the data is acknowledged by the peer. 469 */ 470 471 /* 472 * Append mbuf chain m to the last record in the 473 * socket buffer sb. The additional space associated 474 * the mbuf chain is recorded in sb. Empty mbufs are 475 * discarded and mbufs are compacted where possible. 476 */ 477 void 478 sbappend(sb, m) 479 struct sockbuf *sb; 480 struct mbuf *m; 481 { 482 register struct mbuf *n; 483 484 if (m == 0) 485 return; 486 n = sb->sb_mb; 487 if (n) { 488 while (n->m_nextpkt) 489 n = n->m_nextpkt; 490 do { 491 if (n->m_flags & M_EOR) { 492 sbappendrecord(sb, m); /* XXXXXX!!!! */ 493 return; 494 } 495 } while (n->m_next && (n = n->m_next)); 496 } 497 sbcompress(sb, m, n); 498 } 499 500 #ifdef SOCKBUF_DEBUG 501 void 502 sbcheck(sb) 503 struct sockbuf *sb; 504 { 505 struct mbuf *m; 506 struct mbuf *n = 0; 507 u_long len = 0, mbcnt = 0; 508 509 for (m = sb->sb_mb; m; m = n) { 510 n = m->m_nextpkt; 511 for (; m; m = m->m_next) { 512 len += m->m_len; 513 mbcnt += MSIZE; 514 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 515 mbcnt += m->m_ext.ext_size; 516 } 517 } 518 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 519 printf("cc %ld != %ld || mbcnt %ld != %ld\n", len, sb->sb_cc, 520 mbcnt, sb->sb_mbcnt); 521 panic("sbcheck"); 522 } 523 } 524 #endif 525 526 /* 527 * As above, except the mbuf chain 528 * begins a new record. 529 */ 530 void 531 sbappendrecord(sb, m0) 532 register struct sockbuf *sb; 533 register struct mbuf *m0; 534 { 535 register struct mbuf *m; 536 537 if (m0 == 0) 538 return; 539 m = sb->sb_mb; 540 if (m) 541 while (m->m_nextpkt) 542 m = m->m_nextpkt; 543 /* 544 * Put the first mbuf on the queue. 545 * Note this permits zero length records. 546 */ 547 sballoc(sb, m0); 548 if (m) 549 m->m_nextpkt = m0; 550 else 551 sb->sb_mb = m0; 552 m = m0->m_next; 553 m0->m_next = 0; 554 if (m && (m0->m_flags & M_EOR)) { 555 m0->m_flags &= ~M_EOR; 556 m->m_flags |= M_EOR; 557 } 558 sbcompress(sb, m, m0); 559 } 560 561 /* 562 * As above except that OOB data 563 * is inserted at the beginning of the sockbuf, 564 * but after any other OOB data. 565 */ 566 void 567 sbinsertoob(sb, m0) 568 register struct sockbuf *sb; 569 register struct mbuf *m0; 570 { 571 register struct mbuf *m; 572 register struct mbuf **mp; 573 574 if (m0 == 0) 575 return; 576 for (mp = &sb->sb_mb; *mp ; mp = &((*mp)->m_nextpkt)) { 577 m = *mp; 578 again: 579 switch (m->m_type) { 580 581 case MT_OOBDATA: 582 continue; /* WANT next train */ 583 584 case MT_CONTROL: 585 m = m->m_next; 586 if (m) 587 goto again; /* inspect THIS train further */ 588 } 589 break; 590 } 591 /* 592 * Put the first mbuf on the queue. 593 * Note this permits zero length records. 594 */ 595 sballoc(sb, m0); 596 m0->m_nextpkt = *mp; 597 *mp = m0; 598 m = m0->m_next; 599 m0->m_next = 0; 600 if (m && (m0->m_flags & M_EOR)) { 601 m0->m_flags &= ~M_EOR; 602 m->m_flags |= M_EOR; 603 } 604 sbcompress(sb, m, m0); 605 } 606 607 /* 608 * Append address and data, and optionally, control (ancillary) data 609 * to the receive queue of a socket. If present, 610 * m0 must include a packet header with total length. 611 * Returns 0 if no space in sockbuf or insufficient mbufs. 612 */ 613 int 614 sbappendaddr(sb, asa, m0, control) 615 struct sockbuf *sb; 616 struct sockaddr *asa; 617 struct mbuf *m0, *control; 618 { 619 struct mbuf *m, *n; 620 int space = asa->sa_len; 621 622 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 623 panic("sbappendaddr"); 624 if (m0) 625 space += m0->m_pkthdr.len; 626 space += m_length(control, &n); 627 if (space > sbspace(sb)) 628 return (0); 629 #if MSIZE <= 256 630 if (asa->sa_len > MLEN) 631 return (0); 632 #endif 633 MGET(m, M_DONTWAIT, MT_SONAME); 634 if (m == 0) 635 return (0); 636 m->m_len = asa->sa_len; 637 bcopy(asa, mtod(m, caddr_t), asa->sa_len); 638 if (n) 639 n->m_next = m0; /* concatenate data to control */ 640 else 641 control = m0; 642 m->m_next = control; 643 for (n = m; n; n = n->m_next) 644 sballoc(sb, n); 645 n = sb->sb_mb; 646 if (n) { 647 while (n->m_nextpkt) 648 n = n->m_nextpkt; 649 n->m_nextpkt = m; 650 } else 651 sb->sb_mb = m; 652 return (1); 653 } 654 655 int 656 sbappendcontrol(sb, m0, control) 657 struct sockbuf *sb; 658 struct mbuf *control, *m0; 659 { 660 struct mbuf *m, *n; 661 int space; 662 663 if (control == 0) 664 panic("sbappendcontrol"); 665 space = m_length(control, &n) + m_length(m0, NULL); 666 if (space > sbspace(sb)) 667 return (0); 668 n->m_next = m0; /* concatenate data to control */ 669 for (m = control; m; m = m->m_next) 670 sballoc(sb, m); 671 n = sb->sb_mb; 672 if (n) { 673 while (n->m_nextpkt) 674 n = n->m_nextpkt; 675 n->m_nextpkt = control; 676 } else 677 sb->sb_mb = control; 678 return (1); 679 } 680 681 /* 682 * Compress mbuf chain m into the socket 683 * buffer sb following mbuf n. If n 684 * is null, the buffer is presumed empty. 685 */ 686 void 687 sbcompress(sb, m, n) 688 register struct sockbuf *sb; 689 register struct mbuf *m, *n; 690 { 691 register int eor = 0; 692 register struct mbuf *o; 693 694 while (m) { 695 eor |= m->m_flags & M_EOR; 696 if (m->m_len == 0 && 697 (eor == 0 || 698 (((o = m->m_next) || (o = n)) && 699 o->m_type == m->m_type))) { 700 m = m_free(m); 701 continue; 702 } 703 if (n && (n->m_flags & M_EOR) == 0 && 704 M_WRITABLE(n) && 705 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 706 m->m_len <= M_TRAILINGSPACE(n) && 707 n->m_type == m->m_type) { 708 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, 709 (unsigned)m->m_len); 710 n->m_len += m->m_len; 711 sb->sb_cc += m->m_len; 712 if (m->m_type != MT_DATA && m->m_type != MT_HEADER && 713 m->m_type != MT_OOBDATA) 714 /* XXX: Probably don't need.*/ 715 sb->sb_ctl += m->m_len; 716 m = m_free(m); 717 continue; 718 } 719 if (n) 720 n->m_next = m; 721 else 722 sb->sb_mb = m; 723 sballoc(sb, m); 724 n = m; 725 m->m_flags &= ~M_EOR; 726 m = m->m_next; 727 n->m_next = 0; 728 } 729 if (eor) { 730 if (n) 731 n->m_flags |= eor; 732 else 733 printf("semi-panic: sbcompress\n"); 734 } 735 } 736 737 /* 738 * Free all mbufs in a sockbuf. 739 * Check that all resources are reclaimed. 740 */ 741 void 742 sbflush(sb) 743 register struct sockbuf *sb; 744 { 745 746 if (sb->sb_flags & SB_LOCK) 747 panic("sbflush: locked"); 748 while (sb->sb_mbcnt) { 749 /* 750 * Don't call sbdrop(sb, 0) if the leading mbuf is non-empty: 751 * we would loop forever. Panic instead. 752 */ 753 if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 754 break; 755 sbdrop(sb, (int)sb->sb_cc); 756 } 757 if (sb->sb_cc || sb->sb_mb || sb->sb_mbcnt) 758 panic("sbflush: cc %u || mb %p || mbcnt %u", sb->sb_cc, (void *)sb->sb_mb, sb->sb_mbcnt); 759 } 760 761 /* 762 * Drop data from (the front of) a sockbuf. 763 */ 764 void 765 sbdrop(sb, len) 766 register struct sockbuf *sb; 767 register int len; 768 { 769 register struct mbuf *m; 770 struct mbuf *next; 771 772 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 773 while (len > 0) { 774 if (m == 0) { 775 if (next == 0) 776 panic("sbdrop"); 777 m = next; 778 next = m->m_nextpkt; 779 continue; 780 } 781 if (m->m_len > len) { 782 m->m_len -= len; 783 m->m_data += len; 784 sb->sb_cc -= len; 785 if (m->m_type != MT_DATA && m->m_type != MT_HEADER && 786 m->m_type != MT_OOBDATA) 787 sb->sb_ctl -= len; 788 break; 789 } 790 len -= m->m_len; 791 sbfree(sb, m); 792 m = m_free(m); 793 } 794 while (m && m->m_len == 0) { 795 sbfree(sb, m); 796 m = m_free(m); 797 } 798 if (m) { 799 sb->sb_mb = m; 800 m->m_nextpkt = next; 801 } else 802 sb->sb_mb = next; 803 } 804 805 /* 806 * Drop a record off the front of a sockbuf 807 * and move the next record to the front. 808 */ 809 void 810 sbdroprecord(sb) 811 register struct sockbuf *sb; 812 { 813 register struct mbuf *m; 814 815 m = sb->sb_mb; 816 if (m) { 817 sb->sb_mb = m->m_nextpkt; 818 do { 819 sbfree(sb, m); 820 m = m_free(m); 821 } while (m); 822 } 823 } 824 825 /* 826 * Create a "control" mbuf containing the specified data 827 * with the specified type for presentation on a socket buffer. 828 */ 829 struct mbuf * 830 sbcreatecontrol(p, size, type, level) 831 caddr_t p; 832 register int size; 833 int type, level; 834 { 835 register struct cmsghdr *cp; 836 struct mbuf *m; 837 838 if (CMSG_SPACE((u_int)size) > MCLBYTES) 839 return ((struct mbuf *) NULL); 840 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 841 return ((struct mbuf *) NULL); 842 if (CMSG_SPACE((u_int)size) > MLEN) { 843 MCLGET(m, M_DONTWAIT); 844 if ((m->m_flags & M_EXT) == 0) { 845 m_free(m); 846 return ((struct mbuf *) NULL); 847 } 848 } 849 cp = mtod(m, struct cmsghdr *); 850 m->m_len = 0; 851 KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m), 852 ("sbcreatecontrol: short mbuf")); 853 if (p != NULL) 854 (void)memcpy(CMSG_DATA(cp), p, size); 855 m->m_len = CMSG_SPACE(size); 856 cp->cmsg_len = CMSG_LEN(size); 857 cp->cmsg_level = level; 858 cp->cmsg_type = type; 859 return (m); 860 } 861 862 /* 863 * Some routines that return EOPNOTSUPP for entry points that are not 864 * supported by a protocol. Fill in as needed. 865 */ 866 int 867 pru_accept_notsupp(struct socket *so, struct sockaddr **nam) 868 { 869 return EOPNOTSUPP; 870 } 871 872 int 873 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 874 { 875 return EOPNOTSUPP; 876 } 877 878 int 879 pru_connect2_notsupp(struct socket *so1, struct socket *so2) 880 { 881 return EOPNOTSUPP; 882 } 883 884 int 885 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, 886 struct ifnet *ifp, struct thread *td) 887 { 888 return EOPNOTSUPP; 889 } 890 891 int 892 pru_listen_notsupp(struct socket *so, struct thread *td) 893 { 894 return EOPNOTSUPP; 895 } 896 897 int 898 pru_rcvd_notsupp(struct socket *so, int flags) 899 { 900 return EOPNOTSUPP; 901 } 902 903 int 904 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 905 { 906 return EOPNOTSUPP; 907 } 908 909 /* 910 * This isn't really a ``null'' operation, but it's the default one 911 * and doesn't do anything destructive. 912 */ 913 int 914 pru_sense_null(struct socket *so, struct stat *sb) 915 { 916 sb->st_blksize = so->so_snd.sb_hiwat; 917 return 0; 918 } 919 920 /* 921 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. 922 */ 923 struct sockaddr * 924 dup_sockaddr(sa, canwait) 925 struct sockaddr *sa; 926 int canwait; 927 { 928 struct sockaddr *sa2; 929 930 MALLOC(sa2, struct sockaddr *, sa->sa_len, M_SONAME, 931 canwait ? M_WAITOK : M_NOWAIT); 932 if (sa2) 933 bcopy(sa, sa2, sa->sa_len); 934 return sa2; 935 } 936 937 /* 938 * Create an external-format (``xsocket'') structure using the information 939 * in the kernel-format socket structure pointed to by so. This is done 940 * to reduce the spew of irrelevant information over this interface, 941 * to isolate user code from changes in the kernel structure, and 942 * potentially to provide information-hiding if we decide that 943 * some of this information should be hidden from users. 944 */ 945 void 946 sotoxsocket(struct socket *so, struct xsocket *xso) 947 { 948 xso->xso_len = sizeof *xso; 949 xso->xso_so = so; 950 xso->so_type = so->so_type; 951 xso->so_options = so->so_options; 952 xso->so_linger = so->so_linger; 953 xso->so_state = so->so_state; 954 xso->so_pcb = so->so_pcb; 955 xso->xso_protocol = so->so_proto->pr_protocol; 956 xso->xso_family = so->so_proto->pr_domain->dom_family; 957 xso->so_qlen = so->so_qlen; 958 xso->so_incqlen = so->so_incqlen; 959 xso->so_qlimit = so->so_qlimit; 960 xso->so_timeo = so->so_timeo; 961 xso->so_error = so->so_error; 962 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 963 xso->so_oobmark = so->so_oobmark; 964 sbtoxsockbuf(&so->so_snd, &xso->so_snd); 965 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 966 xso->so_uid = so->so_cred->cr_uid; 967 } 968 969 /* 970 * This does the same for sockbufs. Note that the xsockbuf structure, 971 * since it is always embedded in a socket, does not include a self 972 * pointer nor a length. We make this entry point public in case 973 * some other mechanism needs it. 974 */ 975 void 976 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 977 { 978 xsb->sb_cc = sb->sb_cc; 979 xsb->sb_hiwat = sb->sb_hiwat; 980 xsb->sb_mbcnt = sb->sb_mbcnt; 981 xsb->sb_mbmax = sb->sb_mbmax; 982 xsb->sb_lowat = sb->sb_lowat; 983 xsb->sb_flags = sb->sb_flags; 984 xsb->sb_timeo = sb->sb_timeo; 985 } 986 987 /* 988 * Here is the definition of some of the basic objects in the kern.ipc 989 * branch of the MIB. 990 */ 991 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 992 993 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 994 static int dummy; 995 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 996 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_ULONG|CTLFLAG_RW, 997 &sb_max, 0, sysctl_handle_sb_max, "LU", "Maximum socket buffer size"); 998 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 999 &maxsockets, 0, "Maximum number of sockets avaliable"); 1000 SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1001 &sb_efficiency, 0, ""); 1002 1003 /* 1004 * Initialise maxsockets 1005 */ 1006 static void init_maxsockets(void *ignored) 1007 { 1008 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 1009 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 1010 } 1011 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 1012