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 1.9 2004/04/10 00:48:06 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. 296 * Do asynchronous notification via SIGIO 297 * if the socket has the SS_ASYNC flag set. 298 */ 299 void 300 sowakeup(so, sb) 301 struct socket *so; 302 struct sockbuf *sb; 303 { 304 struct selinfo *selinfo = &sb->sb_sel; 305 306 selwakeup(selinfo); 307 sb->sb_flags &= ~SB_SEL; 308 if (sb->sb_flags & SB_WAIT) { 309 sb->sb_flags &= ~SB_WAIT; 310 wakeup((caddr_t)&sb->sb_cc); 311 } 312 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 313 pgsigio(so->so_sigio, SIGIO, 0); 314 if (sb->sb_flags & SB_UPCALL) 315 (*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT); 316 if (sb->sb_flags & SB_AIO) 317 aio_swake(so, sb); 318 KNOTE(&selinfo->si_note, 0); 319 if (sb->sb_flags & SB_MEVENT) { 320 struct netmsg_so_notify *msg, *nmsg; 321 322 TAILQ_FOREACH_MUTABLE(msg, &selinfo->si_mlist, nm_list, nmsg) { 323 if (msg->nm_predicate((struct netmsg *)msg)) { 324 struct lwkt_msg *lmsg = &msg->nm_lmsg; 325 326 lwkt_replymsg(lmsg, lmsg->ms_error); 327 TAILQ_REMOVE(&selinfo->si_mlist, msg, nm_list); 328 } 329 } 330 331 if (TAILQ_EMPTY(&sb->sb_sel.si_mlist)) 332 sb->sb_flags &= ~SB_MEVENT; 333 } 334 } 335 336 /* 337 * Socket buffer (struct sockbuf) utility routines. 338 * 339 * Each socket contains two socket buffers: one for sending data and 340 * one for receiving data. Each buffer contains a queue of mbufs, 341 * information about the number of mbufs and amount of data in the 342 * queue, and other fields allowing select() statements and notification 343 * on data availability to be implemented. 344 * 345 * Data stored in a socket buffer is maintained as a list of records. 346 * Each record is a list of mbufs chained together with the m_next 347 * field. Records are chained together with the m_nextpkt field. The upper 348 * level routine soreceive() expects the following conventions to be 349 * observed when placing information in the receive buffer: 350 * 351 * 1. If the protocol requires each message be preceded by the sender's 352 * name, then a record containing that name must be present before 353 * any associated data (mbuf's must be of type MT_SONAME). 354 * 2. If the protocol supports the exchange of ``access rights'' (really 355 * just additional data associated with the message), and there are 356 * ``rights'' to be received, then a record containing this data 357 * should be present (mbuf's must be of type MT_RIGHTS). 358 * 3. If a name or rights record exists, then it must be followed by 359 * a data record, perhaps of zero length. 360 * 361 * Before using a new socket structure it is first necessary to reserve 362 * buffer space to the socket, by calling sbreserve(). This should commit 363 * some of the available buffer space in the system buffer pool for the 364 * socket (currently, it does nothing but enforce limits). The space 365 * should be released by calling sbrelease() when the socket is destroyed. 366 */ 367 368 int 369 soreserve(struct socket *so, u_long sndcc, u_long rcvcc, struct rlimit *rl) 370 { 371 if (sbreserve(&so->so_snd, sndcc, so, rl) == 0) 372 goto bad; 373 if (sbreserve(&so->so_rcv, rcvcc, so, rl) == 0) 374 goto bad2; 375 if (so->so_rcv.sb_lowat == 0) 376 so->so_rcv.sb_lowat = 1; 377 if (so->so_snd.sb_lowat == 0) 378 so->so_snd.sb_lowat = MCLBYTES; 379 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 380 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 381 return (0); 382 bad2: 383 sbrelease(&so->so_snd, so); 384 bad: 385 return (ENOBUFS); 386 } 387 388 static int 389 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 390 { 391 int error = 0; 392 u_long old_sb_max = sb_max; 393 394 error = SYSCTL_OUT(req, arg1, sizeof(int)); 395 if (error || !req->newptr) 396 return (error); 397 error = SYSCTL_IN(req, arg1, sizeof(int)); 398 if (error) 399 return (error); 400 if (sb_max < MSIZE + MCLBYTES) { 401 sb_max = old_sb_max; 402 return (EINVAL); 403 } 404 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 405 return (0); 406 } 407 408 /* 409 * Allot mbufs to a sockbuf. 410 * Attempt to scale mbmax so that mbcnt doesn't become limiting 411 * if buffering efficiency is near the normal case. 412 */ 413 int 414 sbreserve(struct sockbuf *sb, u_long cc, struct socket *so, struct rlimit *rl) 415 { 416 417 /* 418 * rl will only be NULL when we're in an interrupt (eg, in tcp_input) 419 * or when called from netgraph (ie, ngd_attach) 420 */ 421 if (cc > sb_max_adj) 422 return (0); 423 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 424 rl ? rl->rlim_cur : RLIM_INFINITY)) { 425 return (0); 426 } 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 /* 474 * Append mbuf chain m to the last record in the 475 * socket buffer sb. The additional space associated 476 * the mbuf chain is recorded in sb. Empty mbufs are 477 * discarded and mbufs are compacted where possible. 478 */ 479 void 480 sbappend(sb, m) 481 struct sockbuf *sb; 482 struct mbuf *m; 483 { 484 struct mbuf *n; 485 486 if (m == 0) 487 return; 488 n = sb->sb_mb; 489 if (n) { 490 while (n->m_nextpkt) 491 n = n->m_nextpkt; 492 do { 493 if (n->m_flags & M_EOR) { 494 sbappendrecord(sb, m); /* XXXXXX!!!! */ 495 return; 496 } 497 } while (n->m_next && (n = n->m_next)); 498 } 499 sbcompress(sb, m, n); 500 } 501 502 #ifdef SOCKBUF_DEBUG 503 void 504 sbcheck(sb) 505 struct sockbuf *sb; 506 { 507 struct mbuf *m; 508 struct mbuf *n = 0; 509 u_long len = 0, mbcnt = 0; 510 511 for (m = sb->sb_mb; m; m = n) { 512 n = m->m_nextpkt; 513 for (; m; m = m->m_next) { 514 len += m->m_len; 515 mbcnt += MSIZE; 516 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 517 mbcnt += m->m_ext.ext_size; 518 } 519 } 520 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 521 printf("cc %ld != %ld || mbcnt %ld != %ld\n", len, sb->sb_cc, 522 mbcnt, sb->sb_mbcnt); 523 panic("sbcheck"); 524 } 525 } 526 #endif 527 528 /* 529 * As above, except the mbuf chain 530 * begins a new record. 531 */ 532 void 533 sbappendrecord(sb, m0) 534 struct sockbuf *sb; 535 struct mbuf *m0; 536 { 537 struct mbuf *m; 538 539 if (m0 == 0) 540 return; 541 m = sb->sb_mb; 542 if (m) 543 while (m->m_nextpkt) 544 m = m->m_nextpkt; 545 /* 546 * Put the first mbuf on the queue. 547 * Note this permits zero length records. 548 */ 549 sballoc(sb, m0); 550 if (m) 551 m->m_nextpkt = m0; 552 else 553 sb->sb_mb = m0; 554 m = m0->m_next; 555 m0->m_next = 0; 556 if (m && (m0->m_flags & M_EOR)) { 557 m0->m_flags &= ~M_EOR; 558 m->m_flags |= M_EOR; 559 } 560 sbcompress(sb, m, m0); 561 } 562 563 /* 564 * As above except that OOB data 565 * is inserted at the beginning of the sockbuf, 566 * but after any other OOB data. 567 */ 568 void 569 sbinsertoob(sb, m0) 570 struct sockbuf *sb; 571 struct mbuf *m0; 572 { 573 struct mbuf *m; 574 struct mbuf **mp; 575 576 if (m0 == 0) 577 return; 578 for (mp = &sb->sb_mb; *mp ; mp = &((*mp)->m_nextpkt)) { 579 m = *mp; 580 again: 581 switch (m->m_type) { 582 583 case MT_OOBDATA: 584 continue; /* WANT next train */ 585 586 case MT_CONTROL: 587 m = m->m_next; 588 if (m) 589 goto again; /* inspect THIS train further */ 590 } 591 break; 592 } 593 /* 594 * Put the first mbuf on the queue. 595 * Note this permits zero length records. 596 */ 597 sballoc(sb, m0); 598 m0->m_nextpkt = *mp; 599 *mp = m0; 600 m = m0->m_next; 601 m0->m_next = 0; 602 if (m && (m0->m_flags & M_EOR)) { 603 m0->m_flags &= ~M_EOR; 604 m->m_flags |= M_EOR; 605 } 606 sbcompress(sb, m, m0); 607 } 608 609 /* 610 * Append address and data, and optionally, control (ancillary) data 611 * to the receive queue of a socket. If present, 612 * m0 must include a packet header with total length. 613 * Returns 0 if no space in sockbuf or insufficient mbufs. 614 */ 615 int 616 sbappendaddr(sb, asa, m0, control) 617 struct sockbuf *sb; 618 struct sockaddr *asa; 619 struct mbuf *m0, *control; 620 { 621 struct mbuf *m, *n; 622 int space = asa->sa_len; 623 624 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 625 panic("sbappendaddr"); 626 627 if (m0) 628 space += m0->m_pkthdr.len; 629 for (n = control; n; n = n->m_next) { 630 space += n->m_len; 631 if (n->m_next == 0) /* keep pointer to last control buf */ 632 break; 633 } 634 if (space > sbspace(sb)) 635 return (0); 636 if (asa->sa_len > MLEN) 637 return (0); 638 MGET(m, M_DONTWAIT, MT_SONAME); 639 if (m == 0) 640 return (0); 641 m->m_len = asa->sa_len; 642 bcopy((caddr_t)asa, mtod(m, caddr_t), asa->sa_len); 643 if (n) 644 n->m_next = m0; /* concatenate data to control */ 645 else 646 control = m0; 647 m->m_next = control; 648 for (n = m; n; n = n->m_next) 649 sballoc(sb, n); 650 n = sb->sb_mb; 651 if (n) { 652 while (n->m_nextpkt) 653 n = n->m_nextpkt; 654 n->m_nextpkt = m; 655 } else 656 sb->sb_mb = m; 657 return (1); 658 } 659 660 int 661 sbappendcontrol(sb, m0, control) 662 struct sockbuf *sb; 663 struct mbuf *control, *m0; 664 { 665 struct mbuf *m, *n; 666 int space = 0; 667 668 if (control == 0) 669 panic("sbappendcontrol"); 670 for (m = control; ; m = m->m_next) { 671 space += m->m_len; 672 if (m->m_next == 0) 673 break; 674 } 675 n = m; /* save pointer to last control buffer */ 676 for (m = m0; m; m = m->m_next) 677 space += m->m_len; 678 if (space > sbspace(sb)) 679 return (0); 680 n->m_next = m0; /* concatenate data to control */ 681 for (m = control; m; m = m->m_next) 682 sballoc(sb, m); 683 n = sb->sb_mb; 684 if (n) { 685 while (n->m_nextpkt) 686 n = n->m_nextpkt; 687 n->m_nextpkt = control; 688 } else 689 sb->sb_mb = control; 690 return (1); 691 } 692 693 /* 694 * Compress mbuf chain m into the socket 695 * buffer sb following mbuf n. If n 696 * is null, the buffer is presumed empty. 697 */ 698 void 699 sbcompress(sb, m, n) 700 struct sockbuf *sb; 701 struct mbuf *m, *n; 702 { 703 int eor = 0; 704 struct mbuf *o; 705 706 while (m) { 707 eor |= m->m_flags & M_EOR; 708 if (m->m_len == 0 && 709 (eor == 0 || 710 (((o = m->m_next) || (o = n)) && 711 o->m_type == m->m_type))) { 712 m = m_free(m); 713 continue; 714 } 715 if (n && (n->m_flags & M_EOR) == 0 && 716 M_WRITABLE(n) && 717 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 718 m->m_len <= M_TRAILINGSPACE(n) && 719 n->m_type == m->m_type) { 720 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, 721 (unsigned)m->m_len); 722 n->m_len += m->m_len; 723 sb->sb_cc += m->m_len; 724 m = m_free(m); 725 continue; 726 } 727 if (n) 728 n->m_next = m; 729 else 730 sb->sb_mb = m; 731 sballoc(sb, m); 732 n = m; 733 m->m_flags &= ~M_EOR; 734 m = m->m_next; 735 n->m_next = 0; 736 } 737 if (eor) { 738 if (n) 739 n->m_flags |= eor; 740 else 741 printf("semi-panic: sbcompress\n"); 742 } 743 } 744 745 /* 746 * Free all mbufs in a sockbuf. 747 * Check that all resources are reclaimed. 748 */ 749 void 750 sbflush(sb) 751 struct sockbuf *sb; 752 { 753 754 if (sb->sb_flags & SB_LOCK) 755 panic("sbflush: locked"); 756 while (sb->sb_mbcnt) { 757 /* 758 * Don't call sbdrop(sb, 0) if the leading mbuf is non-empty: 759 * we would loop forever. Panic instead. 760 */ 761 if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 762 break; 763 sbdrop(sb, (int)sb->sb_cc); 764 } 765 if (sb->sb_cc || sb->sb_mb || sb->sb_mbcnt) 766 panic("sbflush: cc %ld || mb %p || mbcnt %ld", sb->sb_cc, (void *)sb->sb_mb, sb->sb_mbcnt); 767 } 768 769 /* 770 * Drop data from (the front of) a sockbuf. 771 */ 772 void 773 sbdrop(sb, len) 774 struct sockbuf *sb; 775 int len; 776 { 777 struct mbuf *m; 778 struct mbuf *next; 779 780 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 781 while (len > 0) { 782 if (m == 0) { 783 if (next == 0) 784 panic("sbdrop"); 785 m = next; 786 next = m->m_nextpkt; 787 continue; 788 } 789 if (m->m_len > len) { 790 m->m_len -= len; 791 m->m_data += len; 792 sb->sb_cc -= len; 793 break; 794 } 795 len -= m->m_len; 796 sbfree(sb, m); 797 m = m_free(m); 798 } 799 while (m && m->m_len == 0) { 800 sbfree(sb, m); 801 m = m_free(m); 802 } 803 if (m) { 804 sb->sb_mb = m; 805 m->m_nextpkt = next; 806 } else 807 sb->sb_mb = next; 808 } 809 810 /* 811 * Drop a record off the front of a sockbuf 812 * and move the next record to the front. 813 */ 814 void 815 sbdroprecord(sb) 816 struct sockbuf *sb; 817 { 818 struct mbuf *m; 819 820 m = sb->sb_mb; 821 if (m) { 822 sb->sb_mb = m->m_nextpkt; 823 do { 824 sbfree(sb, m); 825 m = m_free(m); 826 } while (m); 827 } 828 } 829 830 /* 831 * Create a "control" mbuf containing the specified data 832 * with the specified type for presentation on a socket buffer. 833 */ 834 struct mbuf * 835 sbcreatecontrol(p, size, type, level) 836 caddr_t p; 837 int size; 838 int type, level; 839 { 840 struct cmsghdr *cp; 841 struct mbuf *m; 842 843 if (CMSG_SPACE((u_int)size) > MCLBYTES) 844 return ((struct mbuf *) NULL); 845 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 846 return ((struct mbuf *) NULL); 847 if (CMSG_SPACE((u_int)size) > MLEN) { 848 MCLGET(m, M_DONTWAIT); 849 if ((m->m_flags & M_EXT) == 0) { 850 m_free(m); 851 return ((struct mbuf *) NULL); 852 } 853 } 854 cp = mtod(m, struct cmsghdr *); 855 m->m_len = 0; 856 KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m), 857 ("sbcreatecontrol: short mbuf")); 858 if (p != NULL) 859 (void)memcpy(CMSG_DATA(cp), p, size); 860 m->m_len = CMSG_SPACE(size); 861 cp->cmsg_len = CMSG_LEN(size); 862 cp->cmsg_level = level; 863 cp->cmsg_type = type; 864 return (m); 865 } 866 867 /* 868 * Some routines that return EOPNOTSUPP for entry points that are not 869 * supported by a protocol. Fill in as needed. 870 */ 871 int 872 pru_accept_notsupp(struct socket *so, struct sockaddr **nam) 873 { 874 return EOPNOTSUPP; 875 } 876 877 int 878 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 879 { 880 return EOPNOTSUPP; 881 } 882 883 int 884 pru_connect2_notsupp(struct socket *so1, struct socket *so2) 885 { 886 return EOPNOTSUPP; 887 } 888 889 int 890 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, 891 struct ifnet *ifp, struct thread *td) 892 { 893 return EOPNOTSUPP; 894 } 895 896 int 897 pru_listen_notsupp(struct socket *so, struct thread *td) 898 { 899 return EOPNOTSUPP; 900 } 901 902 int 903 pru_rcvd_notsupp(struct socket *so, int flags) 904 { 905 return EOPNOTSUPP; 906 } 907 908 int 909 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 910 { 911 return EOPNOTSUPP; 912 } 913 914 /* 915 * This isn't really a ``null'' operation, but it's the default one 916 * and doesn't do anything destructive. 917 */ 918 int 919 pru_sense_null(struct socket *so, struct stat *sb) 920 { 921 sb->st_blksize = so->so_snd.sb_hiwat; 922 return 0; 923 } 924 925 /* 926 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. 927 */ 928 struct sockaddr * 929 dup_sockaddr(sa, canwait) 930 struct sockaddr *sa; 931 int canwait; 932 { 933 struct sockaddr *sa2; 934 935 MALLOC(sa2, struct sockaddr *, sa->sa_len, M_SONAME, 936 canwait ? M_WAITOK : M_NOWAIT); 937 if (sa2) 938 bcopy(sa, sa2, sa->sa_len); 939 return sa2; 940 } 941 942 /* 943 * Create an external-format (``xsocket'') structure using the information 944 * in the kernel-format socket structure pointed to by so. This is done 945 * to reduce the spew of irrelevant information over this interface, 946 * to isolate user code from changes in the kernel structure, and 947 * potentially to provide information-hiding if we decide that 948 * some of this information should be hidden from users. 949 */ 950 void 951 sotoxsocket(struct socket *so, struct xsocket *xso) 952 { 953 xso->xso_len = sizeof *xso; 954 xso->xso_so = so; 955 xso->so_type = so->so_type; 956 xso->so_options = so->so_options; 957 xso->so_linger = so->so_linger; 958 xso->so_state = so->so_state; 959 xso->so_pcb = so->so_pcb; 960 xso->xso_protocol = so->so_proto->pr_protocol; 961 xso->xso_family = so->so_proto->pr_domain->dom_family; 962 xso->so_qlen = so->so_qlen; 963 xso->so_incqlen = so->so_incqlen; 964 xso->so_qlimit = so->so_qlimit; 965 xso->so_timeo = so->so_timeo; 966 xso->so_error = so->so_error; 967 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 968 xso->so_oobmark = so->so_oobmark; 969 sbtoxsockbuf(&so->so_snd, &xso->so_snd); 970 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 971 xso->so_uid = so->so_cred->cr_uid; 972 } 973 974 /* 975 * This does the same for sockbufs. Note that the xsockbuf structure, 976 * since it is always embedded in a socket, does not include a self 977 * pointer nor a length. We make this entry point public in case 978 * some other mechanism needs it. 979 */ 980 void 981 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 982 { 983 xsb->sb_cc = sb->sb_cc; 984 xsb->sb_hiwat = sb->sb_hiwat; 985 xsb->sb_mbcnt = sb->sb_mbcnt; 986 xsb->sb_mbmax = sb->sb_mbmax; 987 xsb->sb_lowat = sb->sb_lowat; 988 xsb->sb_flags = sb->sb_flags; 989 xsb->sb_timeo = sb->sb_timeo; 990 } 991 992 /* 993 * Here is the definition of some of the basic objects in the kern.ipc 994 * branch of the MIB. 995 */ 996 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 997 998 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 999 static int dummy; 1000 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 1001 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_INT|CTLFLAG_RW, 1002 &sb_max, 0, sysctl_handle_sb_max, "I", "Maximum socket buffer size"); 1003 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 1004 &maxsockets, 0, "Maximum number of sockets avaliable"); 1005 SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1006 &sb_efficiency, 0, ""); 1007 1008 /* 1009 * Initialise maxsockets 1010 */ 1011 static void init_maxsockets(void *ignored) 1012 { 1013 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 1014 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 1015 } 1016 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 1017