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: src/sys/kern/uipc_socket2.c,v 1.55.2.17 2002/08/31 19:04:55 dwmalone Exp $ 35 * $DragonFly: src/sys/kern/uipc_socket2.c,v 1.16 2005/03/28 19:53:30 hsu Exp $ 36 */ 37 38 #include "opt_param.h" 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/domain.h> 42 #include <sys/file.h> /* for maxfiles */ 43 #include <sys/kernel.h> 44 #include <sys/proc.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/protosw.h> 48 #include <sys/resourcevar.h> 49 #include <sys/stat.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/signalvar.h> 53 #include <sys/sysctl.h> 54 #include <sys/aio.h> /* for aio_swake proto */ 55 #include <sys/event.h> 56 57 #include <sys/thread2.h> 58 #include <sys/msgport2.h> 59 60 int maxsockets; 61 62 /* 63 * Primitive routines for operating on sockets and socket buffers 64 */ 65 66 u_long sb_max = SB_MAX; 67 u_long sb_max_adj = 68 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */ 69 70 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 71 72 /* 73 * Procedures to manipulate state flags of socket 74 * and do appropriate wakeups. Normal sequence from the 75 * active (originating) side is that soisconnecting() is 76 * called during processing of connect() call, 77 * resulting in an eventual call to soisconnected() if/when the 78 * connection is established. When the connection is torn down 79 * soisdisconnecting() is called during processing of disconnect() call, 80 * and soisdisconnected() is called when the connection to the peer 81 * is totally severed. The semantics of these routines are such that 82 * connectionless protocols can call soisconnected() and soisdisconnected() 83 * only, bypassing the in-progress calls when setting up a ``connection'' 84 * takes no time. 85 * 86 * From the passive side, a socket is created with 87 * two queues of sockets: so_incomp for connections in progress 88 * and so_comp for connections already made and awaiting user acceptance. 89 * As a protocol is preparing incoming connections, it creates a socket 90 * structure queued on so_incomp by calling sonewconn(). When the connection 91 * is established, soisconnected() is called, and transfers the 92 * socket structure to so_comp, making it available to accept(). 93 * 94 * If a socket is closed with sockets on either 95 * so_incomp or so_comp, these sockets are dropped. 96 * 97 * If higher level protocols are implemented in 98 * the kernel, the wakeups done here will sometimes 99 * cause software-interrupt process scheduling. 100 */ 101 102 void 103 soisconnecting(so) 104 struct socket *so; 105 { 106 107 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 108 so->so_state |= SS_ISCONNECTING; 109 } 110 111 void 112 soisconnected(so) 113 struct socket *so; 114 { 115 struct socket *head = so->so_head; 116 117 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 118 so->so_state |= SS_ISCONNECTED; 119 if (head && (so->so_state & SS_INCOMP)) { 120 if ((so->so_options & SO_ACCEPTFILTER) != 0) { 121 so->so_upcall = head->so_accf->so_accept_filter->accf_callback; 122 so->so_upcallarg = head->so_accf->so_accept_filter_arg; 123 so->so_rcv.sb_flags |= SB_UPCALL; 124 so->so_options &= ~SO_ACCEPTFILTER; 125 so->so_upcall(so, so->so_upcallarg, 0); 126 return; 127 } 128 TAILQ_REMOVE(&head->so_incomp, so, so_list); 129 head->so_incqlen--; 130 so->so_state &= ~SS_INCOMP; 131 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 132 head->so_qlen++; 133 so->so_state |= SS_COMP; 134 sorwakeup(head); 135 wakeup_one(&head->so_timeo); 136 } else { 137 wakeup(&so->so_timeo); 138 sorwakeup(so); 139 sowwakeup(so); 140 } 141 } 142 143 void 144 soisdisconnecting(so) 145 struct socket *so; 146 { 147 148 so->so_state &= ~SS_ISCONNECTING; 149 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); 150 wakeup((caddr_t)&so->so_timeo); 151 sowwakeup(so); 152 sorwakeup(so); 153 } 154 155 void 156 soisdisconnected(so) 157 struct socket *so; 158 { 159 160 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 161 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED); 162 wakeup((caddr_t)&so->so_timeo); 163 sbdrop(&so->so_snd, so->so_snd.sb_cc); 164 sowwakeup(so); 165 sorwakeup(so); 166 } 167 168 /* 169 * When an attempt at a new connection is noted on a socket 170 * which accepts connections, sonewconn is called. If the 171 * connection is possible (subject to space constraints, etc.) 172 * then we allocate a new structure, propoerly linked into the 173 * data structure of the original socket, and return this. 174 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 175 */ 176 struct socket * 177 sonewconn(struct socket *head, int connstatus) 178 { 179 struct socket *so; 180 struct pru_attach_info ai; 181 182 if (head->so_qlen > 3 * head->so_qlimit / 2) 183 return ((struct socket *)0); 184 so = soalloc(0); 185 if (so == NULL) 186 return ((struct socket *)0); 187 if ((head->so_options & SO_ACCEPTFILTER) != 0) 188 connstatus = 0; 189 so->so_head = head; 190 so->so_type = head->so_type; 191 so->so_options = head->so_options &~ SO_ACCEPTCONN; 192 so->so_linger = head->so_linger; 193 so->so_state = head->so_state | SS_NOFDREF; 194 so->so_proto = head->so_proto; 195 so->so_timeo = head->so_timeo; 196 so->so_cred = crhold(head->so_cred); 197 ai.sb_rlimit = NULL; 198 ai.p_ucred = NULL; 199 ai.fd_rdir = NULL; /* jail code cruft XXX JH */ 200 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat, NULL) || 201 /* Directly call function since we're already at protocol level. */ 202 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, &ai)) { 203 sodealloc(so); 204 return ((struct socket *)0); 205 } 206 207 if (connstatus) { 208 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 209 so->so_state |= SS_COMP; 210 head->so_qlen++; 211 } else { 212 if (head->so_incqlen > head->so_qlimit) { 213 struct socket *sp; 214 sp = TAILQ_FIRST(&head->so_incomp); 215 (void) soabort(sp); 216 } 217 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 218 so->so_state |= SS_INCOMP; 219 head->so_incqlen++; 220 } 221 if (connstatus) { 222 sorwakeup(head); 223 wakeup((caddr_t)&head->so_timeo); 224 so->so_state |= connstatus; 225 } 226 return (so); 227 } 228 229 /* 230 * Socantsendmore indicates that no more data will be sent on the 231 * socket; it would normally be applied to a socket when the user 232 * informs the system that no more data is to be sent, by the protocol 233 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 234 * will be received, and will normally be applied to the socket by a 235 * protocol when it detects that the peer will send no more data. 236 * Data queued for reading in the socket may yet be read. 237 */ 238 239 void 240 socantsendmore(so) 241 struct socket *so; 242 { 243 244 so->so_state |= SS_CANTSENDMORE; 245 sowwakeup(so); 246 } 247 248 void 249 socantrcvmore(so) 250 struct socket *so; 251 { 252 253 so->so_state |= SS_CANTRCVMORE; 254 sorwakeup(so); 255 } 256 257 /* 258 * Wait for data to arrive at/drain from a socket buffer. 259 */ 260 int 261 sbwait(sb) 262 struct sockbuf *sb; 263 { 264 265 sb->sb_flags |= SB_WAIT; 266 return (tsleep((caddr_t)&sb->sb_cc, 267 ((sb->sb_flags & SB_NOINTR) ? 0 : PCATCH), 268 "sbwait", 269 sb->sb_timeo)); 270 } 271 272 /* 273 * Lock a sockbuf already known to be locked; 274 * return any error returned from sleep (EINTR). 275 */ 276 int 277 sb_lock(sb) 278 struct sockbuf *sb; 279 { 280 int error; 281 282 while (sb->sb_flags & SB_LOCK) { 283 sb->sb_flags |= SB_WANT; 284 error = tsleep((caddr_t)&sb->sb_flags, 285 ((sb->sb_flags & SB_NOINTR) ? 0 : PCATCH), 286 "sblock", 0); 287 if (error) 288 return (error); 289 } 290 sb->sb_flags |= SB_LOCK; 291 return (0); 292 } 293 294 /* 295 * Wakeup processes waiting on a socket buffer. Do asynchronous notification 296 * via SIGIO if the socket has the SS_ASYNC flag set. 297 */ 298 void 299 sowakeup(so, sb) 300 struct socket *so; 301 struct sockbuf *sb; 302 { 303 struct selinfo *selinfo = &sb->sb_sel; 304 305 selwakeup(selinfo); 306 sb->sb_flags &= ~SB_SEL; 307 if (sb->sb_flags & SB_WAIT) { 308 sb->sb_flags &= ~SB_WAIT; 309 wakeup((caddr_t)&sb->sb_cc); 310 } 311 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 312 pgsigio(so->so_sigio, SIGIO, 0); 313 if (sb->sb_flags & SB_UPCALL) 314 (*so->so_upcall)(so, so->so_upcallarg, MB_DONTWAIT); 315 if (sb->sb_flags & SB_AIO) 316 aio_swake(so, sb); 317 KNOTE(&selinfo->si_note, 0); 318 if (sb->sb_flags & SB_MEVENT) { 319 struct netmsg_so_notify *msg, *nmsg; 320 321 TAILQ_FOREACH_MUTABLE(msg, &selinfo->si_mlist, nm_list, nmsg) { 322 if (msg->nm_predicate((struct netmsg *)msg)) { 323 TAILQ_REMOVE(&selinfo->si_mlist, msg, nm_list); 324 lwkt_replymsg(&msg->nm_lmsg, 325 msg->nm_lmsg.ms_error); 326 } 327 } 328 if (TAILQ_EMPTY(&sb->sb_sel.si_mlist)) 329 sb->sb_flags &= ~SB_MEVENT; 330 } 331 } 332 333 /* 334 * Socket buffer (struct sockbuf) utility routines. 335 * 336 * Each socket contains two socket buffers: one for sending data and 337 * one for receiving data. Each buffer contains a queue of mbufs, 338 * information about the number of mbufs and amount of data in the 339 * queue, and other fields allowing select() statements and notification 340 * on data availability to be implemented. 341 * 342 * Data stored in a socket buffer is maintained as a list of records. 343 * Each record is a list of mbufs chained together with the m_next 344 * field. Records are chained together with the m_nextpkt field. The upper 345 * level routine soreceive() expects the following conventions to be 346 * observed when placing information in the receive buffer: 347 * 348 * 1. If the protocol requires each message be preceded by the sender's 349 * name, then a record containing that name must be present before 350 * any associated data (mbuf's must be of type MT_SONAME). 351 * 2. If the protocol supports the exchange of ``access rights'' (really 352 * just additional data associated with the message), and there are 353 * ``rights'' to be received, then a record containing this data 354 * should be present (mbuf's must be of type MT_RIGHTS). 355 * 3. If a name or rights record exists, then it must be followed by 356 * a data record, perhaps of zero length. 357 * 358 * Before using a new socket structure it is first necessary to reserve 359 * buffer space to the socket, by calling sbreserve(). This should commit 360 * some of the available buffer space in the system buffer pool for the 361 * socket (currently, it does nothing but enforce limits). The space 362 * should be released by calling sbrelease() when the socket is destroyed. 363 */ 364 365 int 366 soreserve(struct socket *so, u_long sndcc, u_long rcvcc, struct rlimit *rl) 367 { 368 if (sbreserve(&so->so_snd, sndcc, so, rl) == 0) 369 goto bad; 370 if (sbreserve(&so->so_rcv, rcvcc, so, rl) == 0) 371 goto bad2; 372 if (so->so_rcv.sb_lowat == 0) 373 so->so_rcv.sb_lowat = 1; 374 if (so->so_snd.sb_lowat == 0) 375 so->so_snd.sb_lowat = MCLBYTES; 376 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 377 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 378 return (0); 379 bad2: 380 sbrelease(&so->so_snd, so); 381 bad: 382 return (ENOBUFS); 383 } 384 385 static int 386 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 387 { 388 int error = 0; 389 u_long old_sb_max = sb_max; 390 391 error = SYSCTL_OUT(req, arg1, sizeof(int)); 392 if (error || !req->newptr) 393 return (error); 394 error = SYSCTL_IN(req, arg1, sizeof(int)); 395 if (error) 396 return (error); 397 if (sb_max < MSIZE + MCLBYTES) { 398 sb_max = old_sb_max; 399 return (EINVAL); 400 } 401 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 402 return (0); 403 } 404 405 /* 406 * Allot mbufs to a sockbuf. 407 * Attempt to scale mbmax so that mbcnt doesn't become limiting 408 * if buffering efficiency is near the normal case. 409 */ 410 int 411 sbreserve(struct sockbuf *sb, u_long cc, struct socket *so, struct rlimit *rl) 412 { 413 414 /* 415 * rl will only be NULL when we're in an interrupt (eg, in tcp_input) 416 * or when called from netgraph (ie, ngd_attach) 417 */ 418 if (cc > sb_max_adj) 419 return (0); 420 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 421 rl ? rl->rlim_cur : RLIM_INFINITY)) { 422 return (0); 423 } 424 sb->sb_mbmax = min(cc * sb_efficiency, sb_max); 425 if (sb->sb_lowat > sb->sb_hiwat) 426 sb->sb_lowat = sb->sb_hiwat; 427 return (1); 428 } 429 430 /* 431 * Free mbufs held by a socket, and reserved mbuf space. 432 */ 433 void 434 sbrelease(sb, so) 435 struct sockbuf *sb; 436 struct socket *so; 437 { 438 439 sbflush(sb); 440 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0, 441 RLIM_INFINITY); 442 sb->sb_mbmax = 0; 443 } 444 445 /* 446 * Routines to add and remove 447 * data from an mbuf queue. 448 * 449 * The routines sbappend() or sbappendrecord() are normally called to 450 * append new mbufs to a socket buffer, after checking that adequate 451 * space is available, comparing the function sbspace() with the amount 452 * of data to be added. sbappendrecord() differs from sbappend() in 453 * that data supplied is treated as the beginning of a new record. 454 * To place a sender's address, optional access rights, and data in a 455 * socket receive buffer, sbappendaddr() should be used. To place 456 * access rights and data in a socket receive buffer, sbappendrights() 457 * should be used. In either case, the new data begins a new record. 458 * Note that unlike sbappend() and sbappendrecord(), these routines check 459 * for the caller that there will be enough space to store the data. 460 * Each fails if there is not enough space, or if it cannot find mbufs 461 * to store additional information in. 462 * 463 * Reliable protocols may use the socket send buffer to hold data 464 * awaiting acknowledgement. Data is normally copied from a socket 465 * send buffer in a protocol with m_copy for output to a peer, 466 * and then removing the data from the socket buffer with sbdrop() 467 * or sbdroprecord() when the data is acknowledged by the peer. 468 */ 469 470 /* 471 * Append mbuf chain m to the last record in the 472 * socket buffer sb. The additional space associated 473 * the mbuf chain is recorded in sb. Empty mbufs are 474 * discarded and mbufs are compacted where possible. 475 */ 476 void 477 sbappend(sb, m) 478 struct sockbuf *sb; 479 struct mbuf *m; 480 { 481 struct mbuf *n; 482 boolean_t wasempty = (sb->sb_mb == NULL); 483 484 if (m == 0) 485 return; 486 n = sb->sb_mb; 487 if (n) { 488 n = sb->sb_lastrecord; 489 do { 490 if (n->m_flags & M_EOR) { 491 sbappendrecord(sb, m); /* XXXXXX!!!! */ 492 return; 493 } 494 } while (n->m_next && (n = n->m_next)); 495 } 496 sbcompress(sb, m, n); 497 if (wasempty) 498 sb->sb_lastrecord = sb->sb_mb; 499 } 500 501 /* 502 * sbappendstream() is an optimized form of sbappend() for protocols 503 * such as TCP that only have one record in the socket buffer, are 504 * not PR_ATOMIC, nor allow MT_CONTROL data. A protocol that uses 505 * sbappendstream() must use sbappendstream() exclusively. 506 */ 507 void 508 sbappendstream(struct sockbuf *sb, struct mbuf *m) 509 { 510 KKASSERT(m->m_nextpkt == NULL); 511 sbcompress(sb, m, sb->sb_lastmbuf); 512 } 513 514 #ifdef SOCKBUF_DEBUG 515 void 516 sbcheck(sb) 517 struct sockbuf *sb; 518 { 519 struct mbuf *m; 520 struct mbuf *n = 0; 521 u_long len = 0, mbcnt = 0; 522 523 for (m = sb->sb_mb; m; m = n) { 524 n = m->m_nextpkt; 525 for (; m; m = m->m_next) { 526 len += m->m_len; 527 mbcnt += MSIZE; 528 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 529 mbcnt += m->m_ext.ext_size; 530 } 531 } 532 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 533 printf("cc %ld != %ld || mbcnt %ld != %ld\n", len, sb->sb_cc, 534 mbcnt, sb->sb_mbcnt); 535 panic("sbcheck"); 536 } 537 } 538 #endif 539 540 /* 541 * As above, except the mbuf chain 542 * begins a new record. 543 */ 544 void 545 sbappendrecord(sb, m0) 546 struct sockbuf *sb; 547 struct mbuf *m0; 548 { 549 struct mbuf *m; 550 551 if (m0 == 0) 552 return; 553 554 sballoc(sb, m0); 555 /* 556 * Put the first mbuf on the queue. 557 * Note this permits zero length records. 558 */ 559 if (sb->sb_mb) 560 sb->sb_lastrecord->m_nextpkt = m0; 561 else 562 sb->sb_mb = m0; 563 sb->sb_lastrecord = m0; 564 565 m = m0->m_next; 566 m0->m_next = 0; 567 if (m && (m0->m_flags & M_EOR)) { 568 m0->m_flags &= ~M_EOR; 569 m->m_flags |= M_EOR; 570 } 571 sbcompress(sb, m, m0); 572 } 573 574 /* 575 * As above except that OOB data 576 * is inserted at the beginning of the sockbuf, 577 * but after any other OOB data. 578 */ 579 void 580 sbinsertoob(sb, m0) 581 struct sockbuf *sb; 582 struct mbuf *m0; 583 { 584 struct mbuf *m; 585 struct mbuf **mp; 586 587 if (m0 == 0) 588 return; 589 for (mp = &sb->sb_mb; *mp ; mp = &((*mp)->m_nextpkt)) { 590 m = *mp; 591 again: 592 switch (m->m_type) { 593 594 case MT_OOBDATA: 595 continue; /* WANT next train */ 596 597 case MT_CONTROL: 598 m = m->m_next; 599 if (m) 600 goto again; /* inspect THIS train further */ 601 } 602 break; 603 } 604 /* 605 * Put the first mbuf on the queue. 606 * Note this permits zero length records. 607 */ 608 sballoc(sb, m0); 609 m0->m_nextpkt = *mp; 610 *mp = m0; 611 if (m0->m_nextpkt == NULL) 612 sb->sb_lastrecord = m0; 613 614 m = m0->m_next; 615 m0->m_next = 0; 616 if (m && (m0->m_flags & M_EOR)) { 617 m0->m_flags &= ~M_EOR; 618 m->m_flags |= M_EOR; 619 } 620 sbcompress(sb, m, m0); 621 } 622 623 /* 624 * Append address and data, and optionally, control (ancillary) data 625 * to the receive queue of a socket. If present, 626 * m0 must include a packet header with total length. 627 * Returns 0 if no space in sockbuf or insufficient mbufs. 628 */ 629 int 630 sbappendaddr(sb, asa, m0, control) 631 struct sockbuf *sb; 632 const struct sockaddr *asa; 633 struct mbuf *m0, *control; 634 { 635 struct mbuf *m, *n; 636 int space = asa->sa_len; 637 638 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 639 panic("sbappendaddr"); 640 641 if (m0) 642 space += m0->m_pkthdr.len; 643 for (n = control; n; n = n->m_next) { 644 space += n->m_len; 645 if (n->m_next == 0) /* keep pointer to last control buf */ 646 break; 647 } 648 if (space > sbspace(sb)) 649 return (0); 650 if (asa->sa_len > MLEN) 651 return (0); 652 MGET(m, MB_DONTWAIT, MT_SONAME); 653 if (m == 0) 654 return (0); 655 m->m_len = asa->sa_len; 656 bcopy(asa, mtod(m, caddr_t), asa->sa_len); 657 if (n) 658 n->m_next = m0; /* concatenate data to control */ 659 else 660 control = m0; 661 m->m_next = control; 662 for (n = m; n; n = n->m_next) 663 sballoc(sb, n); 664 665 if (sb->sb_mb) 666 sb->sb_lastrecord->m_nextpkt = m; 667 else 668 sb->sb_mb = m; 669 sb->sb_lastrecord = m; 670 671 return (1); 672 } 673 674 int 675 sbappendcontrol(sb, m0, control) 676 struct sockbuf *sb; 677 struct mbuf *control, *m0; 678 { 679 struct mbuf *m, *n; 680 int space = 0; 681 682 if (control == 0) 683 panic("sbappendcontrol"); 684 for (m = control; ; m = m->m_next) { 685 space += m->m_len; 686 if (m->m_next == 0) 687 break; 688 } 689 n = m; /* save pointer to last control buffer */ 690 for (m = m0; m; m = m->m_next) 691 space += m->m_len; 692 if (space > sbspace(sb)) 693 return (0); 694 n->m_next = m0; /* concatenate data to control */ 695 for (m = control; m; m = m->m_next) 696 sballoc(sb, m); 697 698 if (sb->sb_mb) 699 sb->sb_lastrecord->m_nextpkt = control; 700 else 701 sb->sb_mb = control; 702 sb->sb_lastrecord = control; 703 704 return (1); 705 } 706 707 /* 708 * Compress mbuf chain m into the socket 709 * buffer sb following mbuf n. If n 710 * is null, the buffer is presumed empty. 711 */ 712 void 713 sbcompress(sb, m, n) 714 struct sockbuf *sb; 715 struct mbuf *m, *n; 716 { 717 int eor = 0; 718 struct mbuf *o; 719 720 while (m) { 721 eor |= m->m_flags & M_EOR; 722 if (m->m_len == 0 && 723 (eor == 0 || 724 (((o = m->m_next) || (o = n)) && 725 o->m_type == m->m_type))) { 726 m = m_free(m); 727 continue; 728 } 729 if (n && (n->m_flags & M_EOR) == 0 && 730 M_WRITABLE(n) && 731 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 732 m->m_len <= M_TRAILINGSPACE(n) && 733 n->m_type == m->m_type) { 734 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, 735 (unsigned)m->m_len); 736 n->m_len += m->m_len; 737 sb->sb_cc += m->m_len; 738 m = m_free(m); 739 continue; 740 } 741 if (n) 742 n->m_next = m; 743 else 744 sb->sb_mb = m; 745 sb->sb_lastmbuf = m; 746 sballoc(sb, m); 747 n = m; 748 m->m_flags &= ~M_EOR; 749 m = m->m_next; 750 n->m_next = 0; 751 } 752 if (eor) { 753 if (n) 754 n->m_flags |= eor; 755 else 756 printf("semi-panic: sbcompress"); 757 } 758 } 759 760 /* 761 * Free all mbufs in a sockbuf. 762 * Check that all resources are reclaimed. 763 */ 764 void 765 sbflush(sb) 766 struct sockbuf *sb; 767 { 768 769 if (sb->sb_flags & SB_LOCK) 770 panic("sbflush: locked"); 771 while (sb->sb_mbcnt) { 772 /* 773 * Don't call sbdrop(sb, 0) if the leading mbuf is non-empty: 774 * we would loop forever. Panic instead. 775 */ 776 if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 777 break; 778 sbdrop(sb, (int)sb->sb_cc); 779 } 780 KASSERT(!(sb->sb_cc || sb->sb_mb || sb->sb_mbcnt || sb->sb_lastmbuf), 781 ("sbflush: cc %ld || mb %p || mbcnt %ld || lastmbuf %p", 782 sb->sb_cc, sb->sb_mb, sb->sb_mbcnt, sb->sb_lastmbuf)); 783 } 784 785 /* 786 * Drop data from (the front of) a sockbuf. 787 */ 788 void 789 sbdrop(sb, len) 790 struct sockbuf *sb; 791 int len; 792 { 793 struct mbuf *m; 794 struct mbuf *next; 795 796 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 797 while (len > 0) { 798 if (m == 0) { 799 if (next == 0) 800 panic("sbdrop"); 801 m = next; 802 next = m->m_nextpkt; 803 continue; 804 } 805 if (m->m_len > len) { 806 m->m_len -= len; 807 m->m_data += len; 808 sb->sb_cc -= len; 809 break; 810 } 811 len -= m->m_len; 812 sbfree(sb, m); 813 m = m_free(m); 814 } 815 while (m && m->m_len == 0) { 816 sbfree(sb, m); 817 m = m_free(m); 818 } 819 if (m) { 820 sb->sb_mb = m; 821 m->m_nextpkt = next; 822 } else { 823 sb->sb_mb = next; 824 sb->sb_lastmbuf = NULL; 825 } 826 } 827 828 /* 829 * Drop a record off the front of a sockbuf 830 * and move the next record to the front. 831 */ 832 void 833 sbdroprecord(sb) 834 struct sockbuf *sb; 835 { 836 struct mbuf *m; 837 838 m = sb->sb_mb; 839 if (m) { 840 sb->sb_mb = m->m_nextpkt; 841 do { 842 sbfree(sb, m); 843 m = m_free(m); 844 } while (m); 845 } 846 } 847 848 /* 849 * Create a "control" mbuf containing the specified data 850 * with the specified type for presentation on a socket buffer. 851 */ 852 struct mbuf * 853 sbcreatecontrol(p, size, type, level) 854 caddr_t p; 855 int size; 856 int type, level; 857 { 858 struct cmsghdr *cp; 859 struct mbuf *m; 860 861 if (CMSG_SPACE((u_int)size) > MCLBYTES) 862 return ((struct mbuf *) NULL); 863 if ((m = m_get(MB_DONTWAIT, MT_CONTROL)) == NULL) 864 return ((struct mbuf *) NULL); 865 if (CMSG_SPACE((u_int)size) > MLEN) { 866 MCLGET(m, MB_DONTWAIT); 867 if ((m->m_flags & M_EXT) == 0) { 868 m_free(m); 869 return ((struct mbuf *) NULL); 870 } 871 } 872 cp = mtod(m, struct cmsghdr *); 873 m->m_len = 0; 874 KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m), 875 ("sbcreatecontrol: short mbuf")); 876 if (p != NULL) 877 (void)memcpy(CMSG_DATA(cp), p, size); 878 m->m_len = CMSG_SPACE(size); 879 cp->cmsg_len = CMSG_LEN(size); 880 cp->cmsg_level = level; 881 cp->cmsg_type = type; 882 return (m); 883 } 884 885 /* 886 * Some routines that return EOPNOTSUPP for entry points that are not 887 * supported by a protocol. Fill in as needed. 888 */ 889 int 890 pru_accept_notsupp(struct socket *so, struct sockaddr **nam) 891 { 892 return EOPNOTSUPP; 893 } 894 895 int 896 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 897 { 898 return EOPNOTSUPP; 899 } 900 901 int 902 pru_connect2_notsupp(struct socket *so1, struct socket *so2) 903 { 904 return EOPNOTSUPP; 905 } 906 907 int 908 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, 909 struct ifnet *ifp, struct thread *td) 910 { 911 return EOPNOTSUPP; 912 } 913 914 int 915 pru_listen_notsupp(struct socket *so, struct thread *td) 916 { 917 return EOPNOTSUPP; 918 } 919 920 int 921 pru_rcvd_notsupp(struct socket *so, int flags) 922 { 923 return EOPNOTSUPP; 924 } 925 926 int 927 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 928 { 929 return EOPNOTSUPP; 930 } 931 932 /* 933 * This isn't really a ``null'' operation, but it's the default one 934 * and doesn't do anything destructive. 935 */ 936 int 937 pru_sense_null(struct socket *so, struct stat *sb) 938 { 939 sb->st_blksize = so->so_snd.sb_hiwat; 940 return 0; 941 } 942 943 /* 944 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. Callers 945 * of this routine assume that it always succeeds, so we have to use a 946 * blockable allocation even though we might be called from a critical thread. 947 */ 948 struct sockaddr * 949 dup_sockaddr(const struct sockaddr *sa) 950 { 951 struct sockaddr *sa2; 952 953 sa2 = malloc(sa->sa_len, M_SONAME, M_INTWAIT); 954 bcopy(sa, sa2, sa->sa_len); 955 return (sa2); 956 } 957 958 /* 959 * Create an external-format (``xsocket'') structure using the information 960 * in the kernel-format socket structure pointed to by so. This is done 961 * to reduce the spew of irrelevant information over this interface, 962 * to isolate user code from changes in the kernel structure, and 963 * potentially to provide information-hiding if we decide that 964 * some of this information should be hidden from users. 965 */ 966 void 967 sotoxsocket(struct socket *so, struct xsocket *xso) 968 { 969 xso->xso_len = sizeof *xso; 970 xso->xso_so = so; 971 xso->so_type = so->so_type; 972 xso->so_options = so->so_options; 973 xso->so_linger = so->so_linger; 974 xso->so_state = so->so_state; 975 xso->so_pcb = so->so_pcb; 976 xso->xso_protocol = so->so_proto->pr_protocol; 977 xso->xso_family = so->so_proto->pr_domain->dom_family; 978 xso->so_qlen = so->so_qlen; 979 xso->so_incqlen = so->so_incqlen; 980 xso->so_qlimit = so->so_qlimit; 981 xso->so_timeo = so->so_timeo; 982 xso->so_error = so->so_error; 983 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 984 xso->so_oobmark = so->so_oobmark; 985 sbtoxsockbuf(&so->so_snd, &xso->so_snd); 986 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 987 xso->so_uid = so->so_cred->cr_uid; 988 } 989 990 /* 991 * This does the same for sockbufs. Note that the xsockbuf structure, 992 * since it is always embedded in a socket, does not include a self 993 * pointer nor a length. We make this entry point public in case 994 * some other mechanism needs it. 995 */ 996 void 997 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 998 { 999 xsb->sb_cc = sb->sb_cc; 1000 xsb->sb_hiwat = sb->sb_hiwat; 1001 xsb->sb_mbcnt = sb->sb_mbcnt; 1002 xsb->sb_mbmax = sb->sb_mbmax; 1003 xsb->sb_lowat = sb->sb_lowat; 1004 xsb->sb_flags = sb->sb_flags; 1005 xsb->sb_timeo = sb->sb_timeo; 1006 } 1007 1008 /* 1009 * Here is the definition of some of the basic objects in the kern.ipc 1010 * branch of the MIB. 1011 */ 1012 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 1013 1014 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 1015 static int dummy; 1016 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 1017 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_INT|CTLFLAG_RW, 1018 &sb_max, 0, sysctl_handle_sb_max, "I", "Maximum socket buffer size"); 1019 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 1020 &maxsockets, 0, "Maximum number of sockets avaliable"); 1021 SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1022 &sb_efficiency, 0, ""); 1023 1024 /* 1025 * Initialise maxsockets 1026 */ 1027 static void init_maxsockets(void *ignored) 1028 { 1029 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 1030 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 1031 } 1032 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 1033