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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_mac.h" 36 #include "opt_param.h" 37 38 #include <sys/param.h> 39 #include <sys/aio.h> /* for aio_swake proto */ 40 #include <sys/domain.h> 41 #include <sys/event.h> 42 #include <sys/file.h> /* for maxfiles */ 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/mac.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/mutex.h> 49 #include <sys/proc.h> 50 #include <sys/protosw.h> 51 #include <sys/resourcevar.h> 52 #include <sys/signalvar.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/stat.h> 56 #include <sys/sysctl.h> 57 #include <sys/systm.h> 58 59 int maxsockets; 60 61 void (*aio_swake)(struct socket *, struct sockbuf *); 62 63 /* 64 * Primitive routines for operating on sockets and socket buffers 65 */ 66 67 u_long sb_max = SB_MAX; 68 static u_long sb_max_adj = 69 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */ 70 71 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 72 73 /* 74 * Procedures to manipulate state flags of socket 75 * and do appropriate wakeups. Normal sequence from the 76 * active (originating) side is that soisconnecting() is 77 * called during processing of connect() call, 78 * resulting in an eventual call to soisconnected() if/when the 79 * connection is established. When the connection is torn down 80 * soisdisconnecting() is called during processing of disconnect() call, 81 * and soisdisconnected() is called when the connection to the peer 82 * is totally severed. The semantics of these routines are such that 83 * connectionless protocols can call soisconnected() and soisdisconnected() 84 * only, bypassing the in-progress calls when setting up a ``connection'' 85 * takes no time. 86 * 87 * From the passive side, a socket is created with 88 * two queues of sockets: so_incomp for connections in progress 89 * and so_comp for connections already made and awaiting user acceptance. 90 * As a protocol is preparing incoming connections, it creates a socket 91 * structure queued on so_incomp by calling sonewconn(). When the connection 92 * is established, soisconnected() is called, and transfers the 93 * socket structure to so_comp, making it available to accept(). 94 * 95 * If a socket is closed with sockets on either 96 * so_incomp or so_comp, these sockets are dropped. 97 * 98 * If higher level protocols are implemented in 99 * the kernel, the wakeups done here will sometimes 100 * cause software-interrupt process scheduling. 101 */ 102 103 void 104 soisconnecting(so) 105 register struct socket *so; 106 { 107 108 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 109 so->so_state |= SS_ISCONNECTING; 110 } 111 112 void 113 soisconnected(so) 114 struct socket *so; 115 { 116 struct socket *head = so->so_head; 117 118 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 119 so->so_state |= SS_ISCONNECTED; 120 if (head && (so->so_state & SS_INCOMP)) { 121 if ((so->so_options & SO_ACCEPTFILTER) != 0) { 122 so->so_upcall = head->so_accf->so_accept_filter->accf_callback; 123 so->so_upcallarg = head->so_accf->so_accept_filter_arg; 124 so->so_rcv.sb_flags |= SB_UPCALL; 125 so->so_options &= ~SO_ACCEPTFILTER; 126 so->so_upcall(so, so->so_upcallarg, M_TRYWAIT); 127 return; 128 } 129 TAILQ_REMOVE(&head->so_incomp, so, so_list); 130 head->so_incqlen--; 131 so->so_state &= ~SS_INCOMP; 132 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 133 head->so_qlen++; 134 so->so_state |= SS_COMP; 135 sorwakeup(head); 136 wakeup_one(&head->so_timeo); 137 } else { 138 wakeup(&so->so_timeo); 139 sorwakeup(so); 140 sowwakeup(so); 141 } 142 } 143 144 void 145 soisdisconnecting(so) 146 register struct socket *so; 147 { 148 149 so->so_state &= ~SS_ISCONNECTING; 150 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); 151 wakeup(&so->so_timeo); 152 sowwakeup(so); 153 sorwakeup(so); 154 } 155 156 void 157 soisdisconnected(so) 158 register struct socket *so; 159 { 160 161 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 162 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED); 163 wakeup(&so->so_timeo); 164 sbdrop(&so->so_snd, so->so_snd.sb_cc); 165 sowwakeup(so); 166 sorwakeup(so); 167 } 168 169 /* 170 * When an attempt at a new connection is noted on a socket 171 * which accepts connections, sonewconn is called. If the 172 * connection is possible (subject to space constraints, etc.) 173 * then we allocate a new structure, propoerly linked into the 174 * data structure of the original socket, and return this. 175 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 176 * 177 * note: the ref count on the socket is 0 on return 178 */ 179 struct socket * 180 sonewconn(head, connstatus) 181 register struct socket *head; 182 int connstatus; 183 { 184 register struct socket *so; 185 186 if (head->so_qlen > 3 * head->so_qlimit / 2) 187 return ((struct socket *)0); 188 so = soalloc(M_NOWAIT); 189 if (so == NULL) 190 return ((struct socket *)0); 191 if ((head->so_options & SO_ACCEPTFILTER) != 0) 192 connstatus = 0; 193 so->so_head = head; 194 so->so_type = head->so_type; 195 so->so_options = head->so_options &~ SO_ACCEPTCONN; 196 so->so_linger = head->so_linger; 197 so->so_state = head->so_state | SS_NOFDREF; 198 so->so_proto = head->so_proto; 199 so->so_timeo = head->so_timeo; 200 so->so_cred = crhold(head->so_cred); 201 #ifdef MAC 202 mac_create_socket_from_socket(head, so); 203 #endif 204 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat) || 205 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { 206 sodealloc(so); 207 return ((struct socket *)0); 208 } 209 210 if (connstatus) { 211 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 212 so->so_state |= SS_COMP; 213 head->so_qlen++; 214 } else { 215 if (head->so_incqlen > head->so_qlimit) { 216 struct socket *sp; 217 sp = TAILQ_FIRST(&head->so_incomp); 218 (void) soabort(sp); 219 } 220 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 221 so->so_state |= SS_INCOMP; 222 head->so_incqlen++; 223 } 224 if (connstatus) { 225 sorwakeup(head); 226 wakeup(&head->so_timeo); 227 so->so_state |= connstatus; 228 } 229 return (so); 230 } 231 232 /* 233 * Socantsendmore indicates that no more data will be sent on the 234 * socket; it would normally be applied to a socket when the user 235 * informs the system that no more data is to be sent, by the protocol 236 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 237 * will be received, and will normally be applied to the socket by a 238 * protocol when it detects that the peer will send no more data. 239 * Data queued for reading in the socket may yet be read. 240 */ 241 242 void 243 socantsendmore(so) 244 struct socket *so; 245 { 246 247 so->so_state |= SS_CANTSENDMORE; 248 sowwakeup(so); 249 } 250 251 void 252 socantrcvmore(so) 253 struct socket *so; 254 { 255 256 so->so_state |= SS_CANTRCVMORE; 257 sorwakeup(so); 258 } 259 260 /* 261 * Wait for data to arrive at/drain from a socket buffer. 262 */ 263 int 264 sbwait(sb) 265 struct sockbuf *sb; 266 { 267 268 sb->sb_flags |= SB_WAIT; 269 return (tsleep(&sb->sb_cc, 270 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait", 271 sb->sb_timeo)); 272 } 273 274 /* 275 * Lock a sockbuf already known to be locked; 276 * return any error returned from sleep (EINTR). 277 */ 278 int 279 sb_lock(sb) 280 register struct sockbuf *sb; 281 { 282 int error; 283 284 while (sb->sb_flags & SB_LOCK) { 285 sb->sb_flags |= SB_WANT; 286 error = tsleep(&sb->sb_flags, 287 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK|PCATCH, 288 "sblock", 0); 289 if (error) 290 return (error); 291 } 292 sb->sb_flags |= SB_LOCK; 293 return (0); 294 } 295 296 /* 297 * Wakeup processes waiting on a socket buffer. 298 * Do asynchronous notification via SIGIO 299 * if the socket has the SS_ASYNC flag set. 300 */ 301 void 302 sowakeup(so, sb) 303 register struct socket *so; 304 register struct sockbuf *sb; 305 { 306 307 selwakeuppri(&sb->sb_sel, PSOCK); 308 sb->sb_flags &= ~SB_SEL; 309 if (sb->sb_flags & SB_WAIT) { 310 sb->sb_flags &= ~SB_WAIT; 311 wakeup(&sb->sb_cc); 312 } 313 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 314 pgsigio(&so->so_sigio, SIGIO, 0); 315 if (sb->sb_flags & SB_UPCALL) 316 (*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT); 317 if (sb->sb_flags & SB_AIO) 318 aio_swake(so, sb); 319 KNOTE(&sb->sb_sel.si_note, 0); 320 } 321 322 /* 323 * Socket buffer (struct sockbuf) utility routines. 324 * 325 * Each socket contains two socket buffers: one for sending data and 326 * one for receiving data. Each buffer contains a queue of mbufs, 327 * information about the number of mbufs and amount of data in the 328 * queue, and other fields allowing select() statements and notification 329 * on data availability to be implemented. 330 * 331 * Data stored in a socket buffer is maintained as a list of records. 332 * Each record is a list of mbufs chained together with the m_next 333 * field. Records are chained together with the m_nextpkt field. The upper 334 * level routine soreceive() expects the following conventions to be 335 * observed when placing information in the receive buffer: 336 * 337 * 1. If the protocol requires each message be preceded by the sender's 338 * name, then a record containing that name must be present before 339 * any associated data (mbuf's must be of type MT_SONAME). 340 * 2. If the protocol supports the exchange of ``access rights'' (really 341 * just additional data associated with the message), and there are 342 * ``rights'' to be received, then a record containing this data 343 * should be present (mbuf's must be of type MT_RIGHTS). 344 * 3. If a name or rights record exists, then it must be followed by 345 * a data record, perhaps of zero length. 346 * 347 * Before using a new socket structure it is first necessary to reserve 348 * buffer space to the socket, by calling sbreserve(). This should commit 349 * some of the available buffer space in the system buffer pool for the 350 * socket (currently, it does nothing but enforce limits). The space 351 * should be released by calling sbrelease() when the socket is destroyed. 352 */ 353 354 int 355 soreserve(so, sndcc, rcvcc) 356 register struct socket *so; 357 u_long sndcc, rcvcc; 358 { 359 struct thread *td = curthread; 360 361 if (sbreserve(&so->so_snd, sndcc, so, td) == 0) 362 goto bad; 363 if (sbreserve(&so->so_rcv, rcvcc, so, td) == 0) 364 goto bad2; 365 if (so->so_rcv.sb_lowat == 0) 366 so->so_rcv.sb_lowat = 1; 367 if (so->so_snd.sb_lowat == 0) 368 so->so_snd.sb_lowat = MCLBYTES; 369 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 370 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 371 return (0); 372 bad2: 373 sbrelease(&so->so_snd, so); 374 bad: 375 return (ENOBUFS); 376 } 377 378 static int 379 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 380 { 381 int error = 0; 382 u_long old_sb_max = sb_max; 383 384 error = SYSCTL_OUT(req, arg1, sizeof(u_long)); 385 if (error || !req->newptr) 386 return (error); 387 error = SYSCTL_IN(req, arg1, sizeof(u_long)); 388 if (error) 389 return (error); 390 if (sb_max < MSIZE + MCLBYTES) { 391 sb_max = old_sb_max; 392 return (EINVAL); 393 } 394 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 395 return (0); 396 } 397 398 /* 399 * Allot mbufs to a sockbuf. 400 * Attempt to scale mbmax so that mbcnt doesn't become limiting 401 * if buffering efficiency is near the normal case. 402 */ 403 int 404 sbreserve(sb, cc, so, td) 405 struct sockbuf *sb; 406 u_long cc; 407 struct socket *so; 408 struct thread *td; 409 { 410 rlim_t sbsize_limit; 411 412 /* 413 * td will only be NULL when we're in an interrupt 414 * (e.g. in tcp_input()) 415 */ 416 if (cc > sb_max_adj) 417 return (0); 418 if (td != NULL) { 419 PROC_LOCK(td->td_proc); 420 sbsize_limit = lim_cur(td->td_proc, RLIMIT_SBSIZE); 421 PROC_UNLOCK(td->td_proc); 422 } else 423 sbsize_limit = RLIM_INFINITY; 424 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 425 sbsize_limit)) 426 return (0); 427 sb->sb_mbmax = min(cc * sb_efficiency, sb_max); 428 if (sb->sb_lowat > sb->sb_hiwat) 429 sb->sb_lowat = sb->sb_hiwat; 430 return (1); 431 } 432 433 /* 434 * Free mbufs held by a socket, and reserved mbuf space. 435 */ 436 void 437 sbrelease(sb, so) 438 struct sockbuf *sb; 439 struct socket *so; 440 { 441 442 sbflush(sb); 443 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0, 444 RLIM_INFINITY); 445 sb->sb_mbmax = 0; 446 } 447 448 /* 449 * Routines to add and remove 450 * data from an mbuf queue. 451 * 452 * The routines sbappend() or sbappendrecord() are normally called to 453 * append new mbufs to a socket buffer, after checking that adequate 454 * space is available, comparing the function sbspace() with the amount 455 * of data to be added. sbappendrecord() differs from sbappend() in 456 * that data supplied is treated as the beginning of a new record. 457 * To place a sender's address, optional access rights, and data in a 458 * socket receive buffer, sbappendaddr() should be used. To place 459 * access rights and data in a socket receive buffer, sbappendrights() 460 * should be used. In either case, the new data begins a new record. 461 * Note that unlike sbappend() and sbappendrecord(), these routines check 462 * for the caller that there will be enough space to store the data. 463 * Each fails if there is not enough space, or if it cannot find mbufs 464 * to store additional information in. 465 * 466 * Reliable protocols may use the socket send buffer to hold data 467 * awaiting acknowledgement. Data is normally copied from a socket 468 * send buffer in a protocol with m_copy for output to a peer, 469 * and then removing the data from the socket buffer with sbdrop() 470 * or sbdroprecord() when the data is acknowledged by the peer. 471 */ 472 473 #ifdef SOCKBUF_DEBUG 474 void 475 sblastrecordchk(struct sockbuf *sb, const char *file, int line) 476 { 477 struct mbuf *m = sb->sb_mb; 478 479 while (m && m->m_nextpkt) 480 m = m->m_nextpkt; 481 482 if (m != sb->sb_lastrecord) { 483 printf("%s: sb_mb %p sb_lastrecord %p last %p\n", 484 __func__, sb->sb_mb, sb->sb_lastrecord, m); 485 printf("packet chain:\n"); 486 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) 487 printf("\t%p\n", m); 488 panic("%s from %s:%u", __func__, file, line); 489 } 490 } 491 492 void 493 sblastmbufchk(struct sockbuf *sb, const char *file, int line) 494 { 495 struct mbuf *m = sb->sb_mb; 496 struct mbuf *n; 497 498 while (m && m->m_nextpkt) 499 m = m->m_nextpkt; 500 501 while (m && m->m_next) 502 m = m->m_next; 503 504 if (m != sb->sb_mbtail) { 505 printf("%s: sb_mb %p sb_mbtail %p last %p\n", 506 __func__, sb->sb_mb, sb->sb_mbtail, m); 507 printf("packet tree:\n"); 508 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) { 509 printf("\t"); 510 for (n = m; n != NULL; n = n->m_next) 511 printf("%p ", n); 512 printf("\n"); 513 } 514 panic("%s from %s:%u", __func__, file, line); 515 } 516 } 517 #endif /* SOCKBUF_DEBUG */ 518 519 #define SBLINKRECORD(sb, m0) do { \ 520 if ((sb)->sb_lastrecord != NULL) \ 521 (sb)->sb_lastrecord->m_nextpkt = (m0); \ 522 else \ 523 (sb)->sb_mb = (m0); \ 524 (sb)->sb_lastrecord = (m0); \ 525 } while (/*CONSTCOND*/0) 526 527 /* 528 * Append mbuf chain m to the last record in the 529 * socket buffer sb. The additional space associated 530 * the mbuf chain is recorded in sb. Empty mbufs are 531 * discarded and mbufs are compacted where possible. 532 */ 533 void 534 sbappend(sb, m) 535 struct sockbuf *sb; 536 struct mbuf *m; 537 { 538 register struct mbuf *n; 539 540 if (m == 0) 541 return; 542 SBLASTRECORDCHK(sb); 543 n = sb->sb_mb; 544 if (n) { 545 while (n->m_nextpkt) 546 n = n->m_nextpkt; 547 do { 548 if (n->m_flags & M_EOR) { 549 sbappendrecord(sb, m); /* XXXXXX!!!! */ 550 return; 551 } 552 } while (n->m_next && (n = n->m_next)); 553 } else { 554 /* 555 * XXX Would like to simply use sb_mbtail here, but 556 * XXX I need to verify that I won't miss an EOR that 557 * XXX way. 558 */ 559 if ((n = sb->sb_lastrecord) != NULL) { 560 do { 561 if (n->m_flags & M_EOR) { 562 sbappendrecord(sb, m); /* XXXXXX!!!! */ 563 return; 564 } 565 } while (n->m_next && (n = n->m_next)); 566 } else { 567 /* 568 * If this is the first record in the socket buffer, 569 * it's also the last record. 570 */ 571 sb->sb_lastrecord = m; 572 } 573 } 574 sbcompress(sb, m, n); 575 SBLASTRECORDCHK(sb); 576 } 577 578 /* 579 * This version of sbappend() should only be used when the caller 580 * absolutely knows that there will never be more than one record 581 * in the socket buffer, that is, a stream protocol (such as TCP). 582 */ 583 void 584 sbappendstream(struct sockbuf *sb, struct mbuf *m) 585 { 586 587 KASSERT(m->m_nextpkt == NULL,("sbappendstream 0")); 588 KASSERT(sb->sb_mb == sb->sb_lastrecord,("sbappendstream 1")); 589 590 SBLASTMBUFCHK(sb); 591 592 sbcompress(sb, m, sb->sb_mbtail); 593 594 sb->sb_lastrecord = sb->sb_mb; 595 SBLASTRECORDCHK(sb); 596 } 597 598 #ifdef SOCKBUF_DEBUG 599 void 600 sbcheck(sb) 601 struct sockbuf *sb; 602 { 603 struct mbuf *m; 604 struct mbuf *n = 0; 605 u_long len = 0, mbcnt = 0; 606 607 for (m = sb->sb_mb; m; m = n) { 608 n = m->m_nextpkt; 609 for (; m; m = m->m_next) { 610 len += m->m_len; 611 mbcnt += MSIZE; 612 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 613 mbcnt += m->m_ext.ext_size; 614 } 615 } 616 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 617 printf("cc %ld != %u || mbcnt %ld != %u\n", len, sb->sb_cc, 618 mbcnt, sb->sb_mbcnt); 619 panic("sbcheck"); 620 } 621 } 622 #endif 623 624 /* 625 * As above, except the mbuf chain 626 * begins a new record. 627 */ 628 void 629 sbappendrecord(sb, m0) 630 register struct sockbuf *sb; 631 register struct mbuf *m0; 632 { 633 register struct mbuf *m; 634 635 if (m0 == 0) 636 return; 637 m = sb->sb_mb; 638 if (m) 639 while (m->m_nextpkt) 640 m = m->m_nextpkt; 641 /* 642 * Put the first mbuf on the queue. 643 * Note this permits zero length records. 644 */ 645 sballoc(sb, m0); 646 SBLASTRECORDCHK(sb); 647 SBLINKRECORD(sb, m0); 648 if (m) 649 m->m_nextpkt = m0; 650 else 651 sb->sb_mb = m0; 652 m = m0->m_next; 653 m0->m_next = 0; 654 if (m && (m0->m_flags & M_EOR)) { 655 m0->m_flags &= ~M_EOR; 656 m->m_flags |= M_EOR; 657 } 658 sbcompress(sb, m, m0); 659 } 660 661 /* 662 * As above except that OOB data 663 * is inserted at the beginning of the sockbuf, 664 * but after any other OOB data. 665 */ 666 void 667 sbinsertoob(sb, m0) 668 register struct sockbuf *sb; 669 register struct mbuf *m0; 670 { 671 register struct mbuf *m; 672 register struct mbuf **mp; 673 674 if (m0 == 0) 675 return; 676 for (mp = &sb->sb_mb; *mp ; mp = &((*mp)->m_nextpkt)) { 677 m = *mp; 678 again: 679 switch (m->m_type) { 680 681 case MT_OOBDATA: 682 continue; /* WANT next train */ 683 684 case MT_CONTROL: 685 m = m->m_next; 686 if (m) 687 goto again; /* inspect THIS train further */ 688 } 689 break; 690 } 691 /* 692 * Put the first mbuf on the queue. 693 * Note this permits zero length records. 694 */ 695 sballoc(sb, m0); 696 m0->m_nextpkt = *mp; 697 *mp = m0; 698 m = m0->m_next; 699 m0->m_next = 0; 700 if (m && (m0->m_flags & M_EOR)) { 701 m0->m_flags &= ~M_EOR; 702 m->m_flags |= M_EOR; 703 } 704 sbcompress(sb, m, m0); 705 } 706 707 /* 708 * Append address and data, and optionally, control (ancillary) data 709 * to the receive queue of a socket. If present, 710 * m0 must include a packet header with total length. 711 * Returns 0 if no space in sockbuf or insufficient mbufs. 712 */ 713 int 714 sbappendaddr(sb, asa, m0, control) 715 struct sockbuf *sb; 716 struct sockaddr *asa; 717 struct mbuf *m0, *control; 718 { 719 struct mbuf *m, *n, *nlast; 720 int space = asa->sa_len; 721 722 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 723 panic("sbappendaddr"); 724 if (m0) 725 space += m0->m_pkthdr.len; 726 space += m_length(control, &n); 727 if (space > sbspace(sb)) 728 return (0); 729 #if MSIZE <= 256 730 if (asa->sa_len > MLEN) 731 return (0); 732 #endif 733 MGET(m, M_DONTWAIT, MT_SONAME); 734 if (m == 0) 735 return (0); 736 m->m_len = asa->sa_len; 737 bcopy(asa, mtod(m, caddr_t), asa->sa_len); 738 if (n) 739 n->m_next = m0; /* concatenate data to control */ 740 else 741 control = m0; 742 m->m_next = control; 743 for (n = m; n->m_next != NULL; n = n->m_next) 744 sballoc(sb, n); 745 sballoc(sb, n); 746 nlast = n; 747 SBLINKRECORD(sb, m); 748 749 sb->sb_mbtail = nlast; 750 SBLASTMBUFCHK(sb); 751 752 SBLASTRECORDCHK(sb); 753 return (1); 754 } 755 756 int 757 sbappendcontrol(sb, m0, control) 758 struct sockbuf *sb; 759 struct mbuf *control, *m0; 760 { 761 struct mbuf *m, *n, *mlast; 762 int space; 763 764 if (control == 0) 765 panic("sbappendcontrol"); 766 space = m_length(control, &n) + m_length(m0, NULL); 767 if (space > sbspace(sb)) 768 return (0); 769 n->m_next = m0; /* concatenate data to control */ 770 771 SBLASTRECORDCHK(sb); 772 773 for (m = control; m->m_next; m = m->m_next) 774 sballoc(sb, m); 775 sballoc(sb, m); 776 mlast = m; 777 SBLINKRECORD(sb, control); 778 779 sb->sb_mbtail = mlast; 780 SBLASTMBUFCHK(sb); 781 782 SBLASTRECORDCHK(sb); 783 return (1); 784 } 785 786 /* 787 * Compress mbuf chain m into the socket 788 * buffer sb following mbuf n. If n 789 * is null, the buffer is presumed empty. 790 */ 791 void 792 sbcompress(sb, m, n) 793 register struct sockbuf *sb; 794 register struct mbuf *m, *n; 795 { 796 register int eor = 0; 797 register struct mbuf *o; 798 799 while (m) { 800 eor |= m->m_flags & M_EOR; 801 if (m->m_len == 0 && 802 (eor == 0 || 803 (((o = m->m_next) || (o = n)) && 804 o->m_type == m->m_type))) { 805 if (sb->sb_lastrecord == m) 806 sb->sb_lastrecord = m->m_next; 807 m = m_free(m); 808 continue; 809 } 810 if (n && (n->m_flags & M_EOR) == 0 && 811 M_WRITABLE(n) && 812 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 813 m->m_len <= M_TRAILINGSPACE(n) && 814 n->m_type == m->m_type) { 815 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, 816 (unsigned)m->m_len); 817 n->m_len += m->m_len; 818 sb->sb_cc += m->m_len; 819 if (m->m_type != MT_DATA && m->m_type != MT_HEADER && 820 m->m_type != MT_OOBDATA) 821 /* XXX: Probably don't need.*/ 822 sb->sb_ctl += m->m_len; 823 m = m_free(m); 824 continue; 825 } 826 if (n) 827 n->m_next = m; 828 else 829 sb->sb_mb = m; 830 sb->sb_mbtail = m; 831 sballoc(sb, m); 832 n = m; 833 m->m_flags &= ~M_EOR; 834 m = m->m_next; 835 n->m_next = 0; 836 } 837 if (eor) { 838 if (n) 839 n->m_flags |= eor; 840 else 841 printf("semi-panic: sbcompress\n"); 842 } 843 SBLASTMBUFCHK(sb); 844 } 845 846 /* 847 * Free all mbufs in a sockbuf. 848 * Check that all resources are reclaimed. 849 */ 850 void 851 sbflush(sb) 852 register struct sockbuf *sb; 853 { 854 855 if (sb->sb_flags & SB_LOCK) 856 panic("sbflush: locked"); 857 while (sb->sb_mbcnt) { 858 /* 859 * Don't call sbdrop(sb, 0) if the leading mbuf is non-empty: 860 * we would loop forever. Panic instead. 861 */ 862 if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 863 break; 864 sbdrop(sb, (int)sb->sb_cc); 865 } 866 if (sb->sb_cc || sb->sb_mb || sb->sb_mbcnt) 867 panic("sbflush: cc %u || mb %p || mbcnt %u", sb->sb_cc, (void *)sb->sb_mb, sb->sb_mbcnt); 868 } 869 870 /* 871 * Drop data from (the front of) a sockbuf. 872 */ 873 void 874 sbdrop(sb, len) 875 register struct sockbuf *sb; 876 register int len; 877 { 878 register struct mbuf *m; 879 struct mbuf *next; 880 881 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 882 while (len > 0) { 883 if (m == 0) { 884 if (next == 0) 885 panic("sbdrop"); 886 m = next; 887 next = m->m_nextpkt; 888 continue; 889 } 890 if (m->m_len > len) { 891 m->m_len -= len; 892 m->m_data += len; 893 sb->sb_cc -= len; 894 if (m->m_type != MT_DATA && m->m_type != MT_HEADER && 895 m->m_type != MT_OOBDATA) 896 sb->sb_ctl -= len; 897 break; 898 } 899 len -= m->m_len; 900 sbfree(sb, m); 901 m = m_free(m); 902 } 903 while (m && m->m_len == 0) { 904 sbfree(sb, m); 905 m = m_free(m); 906 } 907 if (m) { 908 sb->sb_mb = m; 909 m->m_nextpkt = next; 910 } else 911 sb->sb_mb = next; 912 /* 913 * First part is an inline SB_EMPTY_FIXUP(). Second part 914 * makes sure sb_lastrecord is up-to-date if we dropped 915 * part of the last record. 916 */ 917 m = sb->sb_mb; 918 if (m == NULL) { 919 sb->sb_mbtail = NULL; 920 sb->sb_lastrecord = NULL; 921 } else if (m->m_nextpkt == NULL) { 922 sb->sb_lastrecord = m; 923 } 924 } 925 926 /* 927 * Drop a record off the front of a sockbuf 928 * and move the next record to the front. 929 */ 930 void 931 sbdroprecord(sb) 932 register struct sockbuf *sb; 933 { 934 register struct mbuf *m; 935 936 m = sb->sb_mb; 937 if (m) { 938 sb->sb_mb = m->m_nextpkt; 939 do { 940 sbfree(sb, m); 941 m = m_free(m); 942 } while (m); 943 } 944 SB_EMPTY_FIXUP(sb); 945 } 946 947 /* 948 * Create a "control" mbuf containing the specified data 949 * with the specified type for presentation on a socket buffer. 950 */ 951 struct mbuf * 952 sbcreatecontrol(p, size, type, level) 953 caddr_t p; 954 register int size; 955 int type, level; 956 { 957 register struct cmsghdr *cp; 958 struct mbuf *m; 959 960 if (CMSG_SPACE((u_int)size) > MCLBYTES) 961 return ((struct mbuf *) NULL); 962 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 963 return ((struct mbuf *) NULL); 964 if (CMSG_SPACE((u_int)size) > MLEN) { 965 MCLGET(m, M_DONTWAIT); 966 if ((m->m_flags & M_EXT) == 0) { 967 m_free(m); 968 return ((struct mbuf *) NULL); 969 } 970 } 971 cp = mtod(m, struct cmsghdr *); 972 m->m_len = 0; 973 KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m), 974 ("sbcreatecontrol: short mbuf")); 975 if (p != NULL) 976 (void)memcpy(CMSG_DATA(cp), p, size); 977 m->m_len = CMSG_SPACE(size); 978 cp->cmsg_len = CMSG_LEN(size); 979 cp->cmsg_level = level; 980 cp->cmsg_type = type; 981 return (m); 982 } 983 984 /* 985 * Some routines that return EOPNOTSUPP for entry points that are not 986 * supported by a protocol. Fill in as needed. 987 */ 988 int 989 pru_accept_notsupp(struct socket *so, struct sockaddr **nam) 990 { 991 return EOPNOTSUPP; 992 } 993 994 int 995 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 996 { 997 return EOPNOTSUPP; 998 } 999 1000 int 1001 pru_connect2_notsupp(struct socket *so1, struct socket *so2) 1002 { 1003 return EOPNOTSUPP; 1004 } 1005 1006 int 1007 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, 1008 struct ifnet *ifp, struct thread *td) 1009 { 1010 return EOPNOTSUPP; 1011 } 1012 1013 int 1014 pru_listen_notsupp(struct socket *so, struct thread *td) 1015 { 1016 return EOPNOTSUPP; 1017 } 1018 1019 int 1020 pru_rcvd_notsupp(struct socket *so, int flags) 1021 { 1022 return EOPNOTSUPP; 1023 } 1024 1025 int 1026 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 1027 { 1028 return EOPNOTSUPP; 1029 } 1030 1031 /* 1032 * This isn't really a ``null'' operation, but it's the default one 1033 * and doesn't do anything destructive. 1034 */ 1035 int 1036 pru_sense_null(struct socket *so, struct stat *sb) 1037 { 1038 sb->st_blksize = so->so_snd.sb_hiwat; 1039 return 0; 1040 } 1041 1042 /* 1043 * For protocol types that don't keep cached copies of labels in their 1044 * pcbs, provide a null sosetlabel that does a NOOP. 1045 */ 1046 void 1047 pru_sosetlabel_null(struct socket *so) 1048 { 1049 1050 } 1051 1052 /* 1053 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. 1054 */ 1055 struct sockaddr * 1056 sodupsockaddr(const struct sockaddr *sa, int mflags) 1057 { 1058 struct sockaddr *sa2; 1059 1060 sa2 = malloc(sa->sa_len, M_SONAME, mflags); 1061 if (sa2) 1062 bcopy(sa, sa2, sa->sa_len); 1063 return sa2; 1064 } 1065 1066 /* 1067 * Create an external-format (``xsocket'') structure using the information 1068 * in the kernel-format socket structure pointed to by so. This is done 1069 * to reduce the spew of irrelevant information over this interface, 1070 * to isolate user code from changes in the kernel structure, and 1071 * potentially to provide information-hiding if we decide that 1072 * some of this information should be hidden from users. 1073 */ 1074 void 1075 sotoxsocket(struct socket *so, struct xsocket *xso) 1076 { 1077 xso->xso_len = sizeof *xso; 1078 xso->xso_so = so; 1079 xso->so_type = so->so_type; 1080 xso->so_options = so->so_options; 1081 xso->so_linger = so->so_linger; 1082 xso->so_state = so->so_state; 1083 xso->so_pcb = so->so_pcb; 1084 xso->xso_protocol = so->so_proto->pr_protocol; 1085 xso->xso_family = so->so_proto->pr_domain->dom_family; 1086 xso->so_qlen = so->so_qlen; 1087 xso->so_incqlen = so->so_incqlen; 1088 xso->so_qlimit = so->so_qlimit; 1089 xso->so_timeo = so->so_timeo; 1090 xso->so_error = so->so_error; 1091 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 1092 xso->so_oobmark = so->so_oobmark; 1093 sbtoxsockbuf(&so->so_snd, &xso->so_snd); 1094 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 1095 xso->so_uid = so->so_cred->cr_uid; 1096 } 1097 1098 /* 1099 * This does the same for sockbufs. Note that the xsockbuf structure, 1100 * since it is always embedded in a socket, does not include a self 1101 * pointer nor a length. We make this entry point public in case 1102 * some other mechanism needs it. 1103 */ 1104 void 1105 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 1106 { 1107 xsb->sb_cc = sb->sb_cc; 1108 xsb->sb_hiwat = sb->sb_hiwat; 1109 xsb->sb_mbcnt = sb->sb_mbcnt; 1110 xsb->sb_mbmax = sb->sb_mbmax; 1111 xsb->sb_lowat = sb->sb_lowat; 1112 xsb->sb_flags = sb->sb_flags; 1113 xsb->sb_timeo = sb->sb_timeo; 1114 } 1115 1116 /* 1117 * Here is the definition of some of the basic objects in the kern.ipc 1118 * branch of the MIB. 1119 */ 1120 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 1121 1122 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 1123 static int dummy; 1124 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 1125 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_ULONG|CTLFLAG_RW, 1126 &sb_max, 0, sysctl_handle_sb_max, "LU", "Maximum socket buffer size"); 1127 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RDTUN, 1128 &maxsockets, 0, "Maximum number of sockets avaliable"); 1129 SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1130 &sb_efficiency, 0, ""); 1131 1132 /* 1133 * Initialise maxsockets 1134 */ 1135 static void init_maxsockets(void *ignored) 1136 { 1137 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 1138 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 1139 } 1140 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 1141