1 /* 2 * Copyright (c) 2005 Jeffrey M. Hsu. All rights reserved. 3 * Copyright (c) 1982, 1986, 1988, 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the University of 17 * California, Berkeley and its contributors. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93 35 * $FreeBSD: src/sys/kern/uipc_socket2.c,v 1.55.2.17 2002/08/31 19:04:55 dwmalone Exp $ 36 * $DragonFly: src/sys/kern/uipc_socket2.c,v 1.33 2008/09/02 16:17:52 dillon Exp $ 37 */ 38 39 #include "opt_param.h" 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/domain.h> 43 #include <sys/file.h> /* for maxfiles */ 44 #include <sys/kernel.h> 45 #include <sys/proc.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/protosw.h> 49 #include <sys/resourcevar.h> 50 #include <sys/stat.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/signalvar.h> 54 #include <sys/sysctl.h> 55 #include <sys/aio.h> /* for aio_swake proto */ 56 #include <sys/event.h> 57 58 #include <sys/thread2.h> 59 #include <sys/msgport2.h> 60 #include <sys/socketvar2.h> 61 62 int maxsockets; 63 64 /* 65 * Primitive routines for operating on sockets and socket buffers 66 */ 67 68 u_long sb_max = SB_MAX; 69 u_long sb_max_adj = 70 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */ 71 72 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 73 74 /************************************************************************ 75 * signalsockbuf procedures * 76 ************************************************************************/ 77 78 /* 79 * Wait for data to arrive at/drain from a socket buffer. 80 * 81 * NOTE: Caller must generally hold the ssb_lock (client side lock) since 82 * WAIT/WAKEUP only works for one client at a time. 83 * 84 * NOTE: Caller always retries whatever operation it was waiting on. 85 */ 86 int 87 ssb_wait(struct signalsockbuf *ssb) 88 { 89 uint32_t flags; 90 int pflags; 91 int error; 92 93 pflags = (ssb->ssb_flags & SSB_NOINTR) ? 0 : PCATCH; 94 95 for (;;) { 96 flags = ssb->ssb_flags; 97 cpu_ccfence(); 98 99 /* 100 * WAKEUP and WAIT interlock eachother. We can catch the 101 * race by checking to see if WAKEUP has already been set, 102 * and only setting WAIT if WAKEUP is clear. 103 */ 104 if (flags & SSB_WAKEUP) { 105 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 106 flags & ~SSB_WAKEUP)) { 107 error = 0; 108 break; 109 } 110 continue; 111 } 112 113 /* 114 * Only set WAIT if WAKEUP is clear. 115 */ 116 tsleep_interlock(&ssb->ssb_cc, pflags); 117 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 118 flags | SSB_WAIT)) { 119 error = tsleep(&ssb->ssb_cc, pflags | PINTERLOCKED, 120 "sbwait", ssb->ssb_timeo); 121 break; 122 } 123 } 124 return (error); 125 } 126 127 /* 128 * Lock a sockbuf already known to be locked; 129 * return any error returned from sleep (EINTR). 130 */ 131 int 132 _ssb_lock(struct signalsockbuf *ssb) 133 { 134 uint32_t flags; 135 int pflags; 136 int error; 137 138 pflags = (ssb->ssb_flags & SSB_NOINTR) ? 0 : PCATCH; 139 140 for (;;) { 141 flags = ssb->ssb_flags; 142 cpu_ccfence(); 143 if (flags & SSB_LOCK) { 144 tsleep_interlock(&ssb->ssb_flags, pflags); 145 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 146 flags | SSB_WANT)) { 147 error = tsleep(&ssb->ssb_flags, 148 pflags | PINTERLOCKED, 149 "sblock", 0); 150 if (error) 151 break; 152 } 153 } else { 154 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 155 flags | SSB_LOCK)) { 156 lwkt_gettoken(&ssb->ssb_token); 157 error = 0; 158 break; 159 } 160 } 161 } 162 return (error); 163 } 164 165 /* 166 * This does the same for sockbufs. Note that the xsockbuf structure, 167 * since it is always embedded in a socket, does not include a self 168 * pointer nor a length. We make this entry point public in case 169 * some other mechanism needs it. 170 */ 171 void 172 ssbtoxsockbuf(struct signalsockbuf *ssb, struct xsockbuf *xsb) 173 { 174 xsb->sb_cc = ssb->ssb_cc; 175 xsb->sb_hiwat = ssb->ssb_hiwat; 176 xsb->sb_mbcnt = ssb->ssb_mbcnt; 177 xsb->sb_mbmax = ssb->ssb_mbmax; 178 xsb->sb_lowat = ssb->ssb_lowat; 179 xsb->sb_flags = ssb->ssb_flags; 180 xsb->sb_timeo = ssb->ssb_timeo; 181 } 182 183 184 /************************************************************************ 185 * Procedures which manipulate socket state flags, wakeups, etc. * 186 ************************************************************************ 187 * 188 * Normal sequence from the active (originating) side is that 189 * soisconnecting() is called during processing of connect() call, resulting 190 * in an eventual call to soisconnected() if/when the connection is 191 * established. When the connection is torn down soisdisconnecting() is 192 * called during processing of disconnect() call, and soisdisconnected() is 193 * called when the connection to the peer is totally severed. 194 * 195 * The semantics of these routines are such that connectionless protocols 196 * can call soisconnected() and soisdisconnected() only, bypassing the 197 * in-progress calls when setting up a ``connection'' takes no time. 198 * 199 * From the passive side, a socket is created with two queues of sockets: 200 * so_incomp for connections in progress and so_comp for connections 201 * already made and awaiting user acceptance. As a protocol is preparing 202 * incoming connections, it creates a socket structure queued on so_incomp 203 * by calling sonewconn(). When the connection is established, 204 * soisconnected() is called, and transfers the socket structure to so_comp, 205 * making it available to accept(). 206 * 207 * If a socket is closed with sockets on either so_incomp or so_comp, these 208 * sockets are dropped. 209 * 210 * If higher level protocols are implemented in the kernel, the wakeups 211 * done here will sometimes cause software-interrupt process scheduling. 212 */ 213 214 void 215 soisconnecting(struct socket *so) 216 { 217 soclrstate(so, SS_ISCONNECTED | SS_ISDISCONNECTING); 218 sosetstate(so, SS_ISCONNECTING); 219 } 220 221 void 222 soisconnected(struct socket *so) 223 { 224 struct socket *head = so->so_head; 225 226 soclrstate(so, SS_ISCONNECTING | SS_ISDISCONNECTING | SS_ISCONFIRMING); 227 sosetstate(so, SS_ISCONNECTED); 228 if (head && (so->so_state & SS_INCOMP)) { 229 if ((so->so_options & SO_ACCEPTFILTER) != 0) { 230 so->so_upcall = head->so_accf->so_accept_filter->accf_callback; 231 so->so_upcallarg = head->so_accf->so_accept_filter_arg; 232 atomic_set_int(&so->so_rcv.ssb_flags, SSB_UPCALL); 233 so->so_options &= ~SO_ACCEPTFILTER; 234 so->so_upcall(so, so->so_upcallarg, 0); 235 return; 236 } 237 238 /* 239 * Listen socket are not per-cpu. 240 */ 241 lwkt_gettoken(&head->so_rcv.ssb_token); 242 TAILQ_REMOVE(&head->so_incomp, so, so_list); 243 head->so_incqlen--; 244 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 245 head->so_qlen++; 246 sosetstate(so, SS_COMP); 247 soclrstate(so, SS_INCOMP); 248 lwkt_reltoken(&head->so_rcv.ssb_token); 249 250 /* 251 * XXX head may be on a different protocol thread. 252 * sorwakeup()->sowakeup() is hacked atm. 253 */ 254 sorwakeup(head); 255 wakeup_one(&head->so_timeo); 256 } else { 257 wakeup(&so->so_timeo); 258 sorwakeup(so); 259 sowwakeup(so); 260 } 261 } 262 263 void 264 soisdisconnecting(struct socket *so) 265 { 266 soclrstate(so, SS_ISCONNECTING); 267 sosetstate(so, SS_ISDISCONNECTING | SS_CANTRCVMORE | SS_CANTSENDMORE); 268 wakeup((caddr_t)&so->so_timeo); 269 sowwakeup(so); 270 sorwakeup(so); 271 } 272 273 void 274 soisdisconnected(struct socket *so) 275 { 276 soclrstate(so, SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING); 277 sosetstate(so, SS_CANTRCVMORE | SS_CANTSENDMORE | SS_ISDISCONNECTED); 278 wakeup((caddr_t)&so->so_timeo); 279 sbdrop(&so->so_snd.sb, so->so_snd.ssb_cc); 280 sowwakeup(so); 281 sorwakeup(so); 282 } 283 284 void 285 soisreconnecting(struct socket *so) 286 { 287 soclrstate(so, SS_ISDISCONNECTING | SS_ISDISCONNECTED | 288 SS_CANTRCVMORE | SS_CANTSENDMORE); 289 sosetstate(so, SS_ISCONNECTING); 290 } 291 292 void 293 soisreconnected(struct socket *so) 294 { 295 soclrstate(so, SS_ISDISCONNECTED | SS_CANTRCVMORE | SS_CANTSENDMORE); 296 soisconnected(so); 297 } 298 299 /* 300 * Set or change the message port a socket receives commands on. 301 * 302 * XXX 303 */ 304 void 305 sosetport(struct socket *so, lwkt_port_t port) 306 { 307 so->so_port = port; 308 } 309 310 /* 311 * When an attempt at a new connection is noted on a socket 312 * which accepts connections, sonewconn is called. If the 313 * connection is possible (subject to space constraints, etc.) 314 * then we allocate a new structure, propoerly linked into the 315 * data structure of the original socket, and return this. 316 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 317 * 318 * The new socket is returned with one ref and so_pcb assigned. 319 * The reference is implied by so_pcb. 320 */ 321 struct socket * 322 sonewconn(struct socket *head, int connstatus) 323 { 324 struct socket *so; 325 struct socket *sp; 326 struct pru_attach_info ai; 327 328 if (head->so_qlen > 3 * head->so_qlimit / 2) 329 return (NULL); 330 so = soalloc(1); 331 if (so == NULL) 332 return (NULL); 333 334 /* 335 * Set the port prior to attaching the inpcb to the current 336 * cpu's protocol thread (which should be the current thread 337 * but might not be in all cases). This serializes any pcb ops 338 * which occur to our cpu allowing us to complete the attachment 339 * without racing anything. 340 */ 341 sosetport(so, cpu_portfn(mycpu->gd_cpuid)); 342 if ((head->so_options & SO_ACCEPTFILTER) != 0) 343 connstatus = 0; 344 so->so_head = head; 345 so->so_type = head->so_type; 346 so->so_options = head->so_options &~ SO_ACCEPTCONN; 347 so->so_linger = head->so_linger; 348 349 /* 350 * NOTE: Clearing NOFDREF implies referencing the so with 351 * soreference(). 352 */ 353 so->so_state = head->so_state | SS_NOFDREF | SS_ASSERTINPROG; 354 so->so_proto = head->so_proto; 355 so->so_cred = crhold(head->so_cred); 356 ai.sb_rlimit = NULL; 357 ai.p_ucred = NULL; 358 ai.fd_rdir = NULL; /* jail code cruft XXX JH */ 359 360 /* 361 * Reserve space and call pru_attach. We can directl call the 362 * function since we're already in the protocol thread. 363 */ 364 if (soreserve(so, head->so_snd.ssb_hiwat, 365 head->so_rcv.ssb_hiwat, NULL) || 366 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, &ai)) { 367 so->so_head = NULL; 368 soclrstate(so, SS_ASSERTINPROG); 369 sofree(so); /* remove implied pcb ref */ 370 return (NULL); 371 } 372 KKASSERT(so->so_refs == 2); /* attach + our base ref */ 373 sofree(so); 374 KKASSERT(so->so_port != NULL); 375 so->so_rcv.ssb_lowat = head->so_rcv.ssb_lowat; 376 so->so_snd.ssb_lowat = head->so_snd.ssb_lowat; 377 so->so_rcv.ssb_timeo = head->so_rcv.ssb_timeo; 378 so->so_snd.ssb_timeo = head->so_snd.ssb_timeo; 379 so->so_rcv.ssb_flags |= head->so_rcv.ssb_flags & 380 (SSB_AUTOSIZE | SSB_AUTOLOWAT); 381 so->so_snd.ssb_flags |= head->so_snd.ssb_flags & 382 (SSB_AUTOSIZE | SSB_AUTOLOWAT); 383 lwkt_gettoken(&head->so_rcv.ssb_token); 384 if (connstatus) { 385 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 386 sosetstate(so, SS_COMP); 387 head->so_qlen++; 388 } else { 389 if (head->so_incqlen > head->so_qlimit) { 390 sp = TAILQ_FIRST(&head->so_incomp); 391 TAILQ_REMOVE(&head->so_incomp, sp, so_list); 392 head->so_incqlen--; 393 soclrstate(sp, SS_INCOMP); 394 sp->so_head = NULL; 395 soaborta(sp); 396 } 397 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 398 sosetstate(so, SS_INCOMP); 399 head->so_incqlen++; 400 } 401 lwkt_reltoken(&head->so_rcv.ssb_token); 402 if (connstatus) { 403 /* 404 * XXX head may be on a different protocol thread. 405 * sorwakeup()->sowakeup() is hacked atm. 406 */ 407 sorwakeup(head); 408 wakeup((caddr_t)&head->so_timeo); 409 sosetstate(so, connstatus); 410 } 411 soclrstate(so, SS_ASSERTINPROG); 412 return (so); 413 } 414 415 /* 416 * Socantsendmore indicates that no more data will be sent on the 417 * socket; it would normally be applied to a socket when the user 418 * informs the system that no more data is to be sent, by the protocol 419 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 420 * will be received, and will normally be applied to the socket by a 421 * protocol when it detects that the peer will send no more data. 422 * Data queued for reading in the socket may yet be read. 423 */ 424 void 425 socantsendmore(struct socket *so) 426 { 427 sosetstate(so, SS_CANTSENDMORE); 428 sowwakeup(so); 429 } 430 431 void 432 socantrcvmore(struct socket *so) 433 { 434 sosetstate(so, SS_CANTRCVMORE); 435 sorwakeup(so); 436 } 437 438 /* 439 * Wakeup processes waiting on a socket buffer. Do asynchronous notification 440 * via SIGIO if the socket has the SS_ASYNC flag set. 441 * 442 * For users waiting on send/recv try to avoid unnecessary context switch 443 * thrashing. Particularly for senders of large buffers (needs to be 444 * extended to sel and aio? XXX) 445 * 446 * WARNING! Can be called on a foreign socket from the wrong protocol 447 * thread. aka is called on the 'head' listen socket when 448 * a new connection comes in. 449 */ 450 void 451 sowakeup(struct socket *so, struct signalsockbuf *ssb) 452 { 453 struct kqinfo *kqinfo = &ssb->ssb_kq; 454 uint32_t flags; 455 456 /* 457 * Check conditions, set the WAKEUP flag, and clear and signal if 458 * the WAIT flag is found to be set. This interlocks against the 459 * client side. 460 */ 461 for (;;) { 462 flags = ssb->ssb_flags; 463 cpu_ccfence(); 464 465 if ((ssb == &so->so_snd && ssb_space(ssb) >= ssb->ssb_lowat) || 466 (ssb == &so->so_rcv && ssb->ssb_cc >= ssb->ssb_lowat) || 467 (ssb == &so->so_snd && (so->so_state & SS_CANTSENDMORE)) || 468 (ssb == &so->so_rcv && (so->so_state & SS_CANTRCVMORE)) 469 ) { 470 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 471 (flags | SSB_WAKEUP) & ~SSB_WAIT)) { 472 if (flags & SSB_WAIT) 473 wakeup(&ssb->ssb_cc); 474 break; 475 } 476 } else { 477 break; 478 } 479 } 480 481 /* 482 * Misc other events 483 */ 484 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 485 pgsigio(so->so_sigio, SIGIO, 0); 486 if (ssb->ssb_flags & SSB_UPCALL) 487 (*so->so_upcall)(so, so->so_upcallarg, MB_DONTWAIT); 488 if (ssb->ssb_flags & SSB_AIO) 489 aio_swake(so, ssb); 490 KNOTE(&kqinfo->ki_note, 0); 491 492 /* 493 * This is a bit of a hack. Multiple threads can wind up scanning 494 * ki_mlist concurrently due to the fact that this function can be 495 * called on a foreign socket, so we can't afford to block here. 496 */ 497 if (ssb->ssb_flags & SSB_MEVENT) { 498 struct netmsg_so_notify *msg, *nmsg; 499 500 lwkt_gettoken(&kq_token); 501 lwkt_gettoken_hard(&ssb->ssb_token); 502 TAILQ_FOREACH_MUTABLE(msg, &kqinfo->ki_mlist, nm_list, nmsg) { 503 if (msg->nm_predicate(&msg->nm_netmsg)) { 504 TAILQ_REMOVE(&kqinfo->ki_mlist, msg, nm_list); 505 lwkt_replymsg(&msg->nm_netmsg.nm_lmsg, 506 msg->nm_netmsg.nm_lmsg.ms_error); 507 } 508 } 509 if (TAILQ_EMPTY(&ssb->ssb_kq.ki_mlist)) 510 atomic_clear_int(&ssb->ssb_flags, SSB_MEVENT); 511 lwkt_reltoken_hard(&ssb->ssb_token); 512 lwkt_reltoken(&kq_token); 513 } 514 } 515 516 /* 517 * Socket buffer (struct signalsockbuf) utility routines. 518 * 519 * Each socket contains two socket buffers: one for sending data and 520 * one for receiving data. Each buffer contains a queue of mbufs, 521 * information about the number of mbufs and amount of data in the 522 * queue, and other fields allowing kevent()/select()/poll() statements 523 * and notification on data availability to be implemented. 524 * 525 * Data stored in a socket buffer is maintained as a list of records. 526 * Each record is a list of mbufs chained together with the m_next 527 * field. Records are chained together with the m_nextpkt field. The upper 528 * level routine soreceive() expects the following conventions to be 529 * observed when placing information in the receive buffer: 530 * 531 * 1. If the protocol requires each message be preceded by the sender's 532 * name, then a record containing that name must be present before 533 * any associated data (mbuf's must be of type MT_SONAME). 534 * 2. If the protocol supports the exchange of ``access rights'' (really 535 * just additional data associated with the message), and there are 536 * ``rights'' to be received, then a record containing this data 537 * should be present (mbuf's must be of type MT_RIGHTS). 538 * 3. If a name or rights record exists, then it must be followed by 539 * a data record, perhaps of zero length. 540 * 541 * Before using a new socket structure it is first necessary to reserve 542 * buffer space to the socket, by calling sbreserve(). This should commit 543 * some of the available buffer space in the system buffer pool for the 544 * socket (currently, it does nothing but enforce limits). The space 545 * should be released by calling ssb_release() when the socket is destroyed. 546 */ 547 int 548 soreserve(struct socket *so, u_long sndcc, u_long rcvcc, struct rlimit *rl) 549 { 550 if (so->so_snd.ssb_lowat == 0) 551 atomic_set_int(&so->so_snd.ssb_flags, SSB_AUTOLOWAT); 552 if (ssb_reserve(&so->so_snd, sndcc, so, rl) == 0) 553 goto bad; 554 if (ssb_reserve(&so->so_rcv, rcvcc, so, rl) == 0) 555 goto bad2; 556 if (so->so_rcv.ssb_lowat == 0) 557 so->so_rcv.ssb_lowat = 1; 558 if (so->so_snd.ssb_lowat == 0) 559 so->so_snd.ssb_lowat = MCLBYTES; 560 if (so->so_snd.ssb_lowat > so->so_snd.ssb_hiwat) 561 so->so_snd.ssb_lowat = so->so_snd.ssb_hiwat; 562 return (0); 563 bad2: 564 ssb_release(&so->so_snd, so); 565 bad: 566 return (ENOBUFS); 567 } 568 569 static int 570 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 571 { 572 int error = 0; 573 u_long old_sb_max = sb_max; 574 575 error = SYSCTL_OUT(req, arg1, sizeof(int)); 576 if (error || !req->newptr) 577 return (error); 578 error = SYSCTL_IN(req, arg1, sizeof(int)); 579 if (error) 580 return (error); 581 if (sb_max < MSIZE + MCLBYTES) { 582 sb_max = old_sb_max; 583 return (EINVAL); 584 } 585 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 586 return (0); 587 } 588 589 /* 590 * Allot mbufs to a signalsockbuf. 591 * 592 * Attempt to scale mbmax so that mbcnt doesn't become limiting 593 * if buffering efficiency is near the normal case. 594 * 595 * sb_max only applies to user-sockets (where rl != NULL). It does 596 * not apply to kernel sockets or kernel-controlled sockets. Note 597 * that NFS overrides the sockbuf limits created when nfsd creates 598 * a socket. 599 */ 600 int 601 ssb_reserve(struct signalsockbuf *ssb, u_long cc, struct socket *so, 602 struct rlimit *rl) 603 { 604 /* 605 * rl will only be NULL when we're in an interrupt (eg, in tcp_input) 606 * or when called from netgraph (ie, ngd_attach) 607 */ 608 if (rl && cc > sb_max_adj) 609 cc = sb_max_adj; 610 if (!chgsbsize(so->so_cred->cr_uidinfo, &ssb->ssb_hiwat, cc, 611 rl ? rl->rlim_cur : RLIM_INFINITY)) { 612 return (0); 613 } 614 if (rl) 615 ssb->ssb_mbmax = min(cc * sb_efficiency, sb_max); 616 else 617 ssb->ssb_mbmax = cc * sb_efficiency; 618 619 /* 620 * AUTOLOWAT is set on send buffers and prevents large writes 621 * from generating a huge number of context switches. 622 */ 623 if (ssb->ssb_flags & SSB_AUTOLOWAT) { 624 ssb->ssb_lowat = ssb->ssb_hiwat / 2; 625 if (ssb->ssb_lowat < MCLBYTES) 626 ssb->ssb_lowat = MCLBYTES; 627 } 628 if (ssb->ssb_lowat > ssb->ssb_hiwat) 629 ssb->ssb_lowat = ssb->ssb_hiwat; 630 return (1); 631 } 632 633 /* 634 * Free mbufs held by a socket, and reserved mbuf space. 635 */ 636 void 637 ssb_release(struct signalsockbuf *ssb, struct socket *so) 638 { 639 sbflush(&ssb->sb); 640 (void)chgsbsize(so->so_cred->cr_uidinfo, &ssb->ssb_hiwat, 0, 641 RLIM_INFINITY); 642 ssb->ssb_mbmax = 0; 643 } 644 645 /* 646 * Some routines that return EOPNOTSUPP for entry points that are not 647 * supported by a protocol. Fill in as needed. 648 */ 649 int 650 pru_accept_notsupp(struct socket *so, struct sockaddr **nam) 651 { 652 return EOPNOTSUPP; 653 } 654 655 int 656 pru_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 657 { 658 return EOPNOTSUPP; 659 } 660 661 int 662 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) 663 { 664 return EOPNOTSUPP; 665 } 666 667 int 668 pru_connect2_notsupp(struct socket *so1, struct socket *so2) 669 { 670 return EOPNOTSUPP; 671 } 672 673 int 674 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, 675 struct ifnet *ifp, struct thread *td) 676 { 677 return EOPNOTSUPP; 678 } 679 680 int 681 pru_disconnect_notsupp(struct socket *so) 682 { 683 return EOPNOTSUPP; 684 } 685 686 int 687 pru_listen_notsupp(struct socket *so, struct thread *td) 688 { 689 return EOPNOTSUPP; 690 } 691 692 int 693 pru_peeraddr_notsupp(struct socket *so, struct sockaddr **nam) 694 { 695 return EOPNOTSUPP; 696 } 697 698 int 699 pru_rcvd_notsupp(struct socket *so, int flags) 700 { 701 return EOPNOTSUPP; 702 } 703 704 int 705 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) 706 { 707 return EOPNOTSUPP; 708 } 709 710 int 711 pru_shutdown_notsupp(struct socket *so) 712 { 713 return EOPNOTSUPP; 714 } 715 716 int 717 pru_sockaddr_notsupp(struct socket *so, struct sockaddr **nam) 718 { 719 return EOPNOTSUPP; 720 } 721 722 int 723 pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio, 724 struct mbuf *top, struct mbuf *control, int flags, 725 struct thread *td) 726 { 727 if (top) 728 m_freem(top); 729 if (control) 730 m_freem(control); 731 return (EOPNOTSUPP); 732 } 733 734 int 735 pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr, 736 struct uio *uio, struct sockbuf *sio, 737 struct mbuf **controlp, int *flagsp) 738 { 739 return (EOPNOTSUPP); 740 } 741 742 int 743 pru_ctloutput_notsupp(struct socket *so, struct sockopt *sopt) 744 { 745 return (EOPNOTSUPP); 746 } 747 748 /* 749 * This isn't really a ``null'' operation, but it's the default one 750 * and doesn't do anything destructive. 751 */ 752 int 753 pru_sense_null(struct socket *so, struct stat *sb) 754 { 755 sb->st_blksize = so->so_snd.ssb_hiwat; 756 return 0; 757 } 758 759 /* 760 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. Callers 761 * of this routine assume that it always succeeds, so we have to use a 762 * blockable allocation even though we might be called from a critical thread. 763 */ 764 struct sockaddr * 765 dup_sockaddr(const struct sockaddr *sa) 766 { 767 struct sockaddr *sa2; 768 769 sa2 = kmalloc(sa->sa_len, M_SONAME, M_INTWAIT); 770 bcopy(sa, sa2, sa->sa_len); 771 return (sa2); 772 } 773 774 /* 775 * Create an external-format (``xsocket'') structure using the information 776 * in the kernel-format socket structure pointed to by so. This is done 777 * to reduce the spew of irrelevant information over this interface, 778 * to isolate user code from changes in the kernel structure, and 779 * potentially to provide information-hiding if we decide that 780 * some of this information should be hidden from users. 781 */ 782 void 783 sotoxsocket(struct socket *so, struct xsocket *xso) 784 { 785 xso->xso_len = sizeof *xso; 786 xso->xso_so = so; 787 xso->so_type = so->so_type; 788 xso->so_options = so->so_options; 789 xso->so_linger = so->so_linger; 790 xso->so_state = so->so_state; 791 xso->so_pcb = so->so_pcb; 792 xso->xso_protocol = so->so_proto->pr_protocol; 793 xso->xso_family = so->so_proto->pr_domain->dom_family; 794 xso->so_qlen = so->so_qlen; 795 xso->so_incqlen = so->so_incqlen; 796 xso->so_qlimit = so->so_qlimit; 797 xso->so_timeo = so->so_timeo; 798 xso->so_error = so->so_error; 799 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 800 xso->so_oobmark = so->so_oobmark; 801 ssbtoxsockbuf(&so->so_snd, &xso->so_snd); 802 ssbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 803 xso->so_uid = so->so_cred->cr_uid; 804 } 805 806 /* 807 * Here is the definition of some of the basic objects in the kern.ipc 808 * branch of the MIB. 809 */ 810 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 811 812 /* 813 * This takes the place of kern.maxsockbuf, which moved to kern.ipc. 814 * 815 * NOTE! sb_max only applies to user-created socket buffers. 816 */ 817 static int dummy; 818 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 819 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_INT|CTLFLAG_RW, 820 &sb_max, 0, sysctl_handle_sb_max, "I", "Maximum socket buffer size"); 821 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 822 &maxsockets, 0, "Maximum number of sockets available"); 823 SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 824 &sb_efficiency, 0, ""); 825 826 /* 827 * Initialize maxsockets 828 */ 829 static void 830 init_maxsockets(void *ignored) 831 { 832 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 833 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 834 } 835 SYSINIT(param, SI_BOOT1_TUNABLES, SI_ORDER_ANY, 836 init_maxsockets, NULL); 837 838