Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/uipc_sockbuf.c
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1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_kern_tls.h" 38 #include "opt_param.h" 39 40 #include <sys/param.h> 41 #include <sys/aio.h> /* for aio_swake proto */ 42 #include <sys/kernel.h> 43 #include <sys/ktls.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/mutex.h> 48 #include <sys/proc.h> 49 #include <sys/protosw.h> 50 #include <sys/resourcevar.h> 51 #include <sys/signalvar.h> 52 #include <sys/socket.h> 53 #include <sys/socketvar.h> 54 #include <sys/sx.h> 55 #include <sys/sysctl.h> 56 57 #include <netinet/in.h> 58 59 /* 60 * Function pointer set by the AIO routines so that the socket buffer code 61 * can call back into the AIO module if it is loaded. 62 */ 63 void (*aio_swake)(struct socket *, struct sockbuf *); 64 65 /* 66 * Primitive routines for operating on socket buffers 67 */ 68 69 #define BUF_MAX_ADJ(_sz) (((u_quad_t)(_sz)) * MCLBYTES / (MSIZE + MCLBYTES)) 70 71 u_long sb_max = SB_MAX; 72 u_long sb_max_adj = BUF_MAX_ADJ(SB_MAX); 73 74 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 75 76 #ifdef KERN_TLS 77 static void sbcompress_ktls_rx(struct sockbuf *sb, struct mbuf *m, 78 struct mbuf *n); 79 #endif 80 static struct mbuf *sbcut_internal(struct sockbuf *sb, int len); 81 static void sbflush_internal(struct sockbuf *sb); 82 83 /* 84 * Our own version of m_clrprotoflags(), that can preserve M_NOTREADY. 85 */ 86 static void 87 sbm_clrprotoflags(struct mbuf *m, int flags) 88 { 89 int mask; 90 91 mask = ~M_PROTOFLAGS; 92 if (flags & PRUS_NOTREADY) 93 mask |= M_NOTREADY; 94 while (m) { 95 m->m_flags &= mask; 96 m = m->m_next; 97 } 98 } 99 100 /* 101 * Compress M_NOTREADY mbufs after they have been readied by sbready(). 102 * 103 * sbcompress() skips M_NOTREADY mbufs since the data is not available to 104 * be copied at the time of sbcompress(). This function combines small 105 * mbufs similar to sbcompress() once mbufs are ready. 'm0' is the first 106 * mbuf sbready() marked ready, and 'end' is the first mbuf still not 107 * ready. 108 */ 109 static void 110 sbready_compress(struct sockbuf *sb, struct mbuf *m0, struct mbuf *end) 111 { 112 struct mbuf *m, *n; 113 int ext_size; 114 115 SOCKBUF_LOCK_ASSERT(sb); 116 117 if ((sb->sb_flags & SB_NOCOALESCE) != 0) 118 return; 119 120 for (m = m0; m != end; m = m->m_next) { 121 MPASS((m->m_flags & M_NOTREADY) == 0); 122 /* 123 * NB: In sbcompress(), 'n' is the last mbuf in the 124 * socket buffer and 'm' is the new mbuf being copied 125 * into the trailing space of 'n'. Here, the roles 126 * are reversed and 'n' is the next mbuf after 'm' 127 * that is being copied into the trailing space of 128 * 'm'. 129 */ 130 n = m->m_next; 131 #ifdef KERN_TLS 132 /* Try to coalesce adjacent ktls mbuf hdr/trailers. */ 133 if ((n != NULL) && (n != end) && (m->m_flags & M_EOR) == 0 && 134 (m->m_flags & M_EXTPG) && 135 (n->m_flags & M_EXTPG) && 136 !mbuf_has_tls_session(m) && 137 !mbuf_has_tls_session(n)) { 138 int hdr_len, trail_len; 139 140 hdr_len = n->m_epg_hdrlen; 141 trail_len = m->m_epg_trllen; 142 if (trail_len != 0 && hdr_len != 0 && 143 trail_len + hdr_len <= MBUF_PEXT_TRAIL_LEN) { 144 /* copy n's header to m's trailer */ 145 memcpy(&m->m_epg_trail[trail_len], 146 n->m_epg_hdr, hdr_len); 147 m->m_epg_trllen += hdr_len; 148 m->m_len += hdr_len; 149 n->m_epg_hdrlen = 0; 150 n->m_len -= hdr_len; 151 } 152 } 153 #endif 154 155 /* Compress small unmapped mbufs into plain mbufs. */ 156 if ((m->m_flags & M_EXTPG) && m->m_len <= MLEN && 157 !mbuf_has_tls_session(m)) { 158 ext_size = m->m_ext.ext_size; 159 if (mb_unmapped_compress(m) == 0) 160 sb->sb_mbcnt -= ext_size; 161 } 162 163 while ((n != NULL) && (n != end) && (m->m_flags & M_EOR) == 0 && 164 M_WRITABLE(m) && 165 (m->m_flags & M_EXTPG) == 0 && 166 !mbuf_has_tls_session(n) && 167 !mbuf_has_tls_session(m) && 168 n->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 169 n->m_len <= M_TRAILINGSPACE(m) && 170 m->m_type == n->m_type) { 171 KASSERT(sb->sb_lastrecord != n, 172 ("%s: merging start of record (%p) into previous mbuf (%p)", 173 __func__, n, m)); 174 m_copydata(n, 0, n->m_len, mtodo(m, m->m_len)); 175 m->m_len += n->m_len; 176 m->m_next = n->m_next; 177 m->m_flags |= n->m_flags & M_EOR; 178 if (sb->sb_mbtail == n) 179 sb->sb_mbtail = m; 180 181 sb->sb_mbcnt -= MSIZE; 182 if (n->m_flags & M_EXT) 183 sb->sb_mbcnt -= n->m_ext.ext_size; 184 m_free(n); 185 n = m->m_next; 186 } 187 } 188 SBLASTRECORDCHK(sb); 189 SBLASTMBUFCHK(sb); 190 } 191 192 /* 193 * Mark ready "count" units of I/O starting with "m". Most mbufs 194 * count as a single unit of I/O except for M_EXTPG mbufs which 195 * are backed by multiple pages. 196 */ 197 int 198 sbready(struct sockbuf *sb, struct mbuf *m0, int count) 199 { 200 struct mbuf *m; 201 u_int blocker; 202 203 SOCKBUF_LOCK_ASSERT(sb); 204 KASSERT(sb->sb_fnrdy != NULL, ("%s: sb %p NULL fnrdy", __func__, sb)); 205 KASSERT(count > 0, ("%s: invalid count %d", __func__, count)); 206 207 m = m0; 208 blocker = (sb->sb_fnrdy == m) ? M_BLOCKED : 0; 209 210 while (count > 0) { 211 KASSERT(m->m_flags & M_NOTREADY, 212 ("%s: m %p !M_NOTREADY", __func__, m)); 213 if ((m->m_flags & M_EXTPG) != 0 && m->m_epg_npgs != 0) { 214 if (count < m->m_epg_nrdy) { 215 m->m_epg_nrdy -= count; 216 count = 0; 217 break; 218 } 219 count -= m->m_epg_nrdy; 220 m->m_epg_nrdy = 0; 221 } else 222 count--; 223 224 m->m_flags &= ~(M_NOTREADY | blocker); 225 if (blocker) 226 sb->sb_acc += m->m_len; 227 m = m->m_next; 228 } 229 230 /* 231 * If the first mbuf is still not fully ready because only 232 * some of its backing pages were readied, no further progress 233 * can be made. 234 */ 235 if (m0 == m) { 236 MPASS(m->m_flags & M_NOTREADY); 237 return (EINPROGRESS); 238 } 239 240 if (!blocker) { 241 sbready_compress(sb, m0, m); 242 return (EINPROGRESS); 243 } 244 245 /* This one was blocking all the queue. */ 246 for (; m && (m->m_flags & M_NOTREADY) == 0; m = m->m_next) { 247 KASSERT(m->m_flags & M_BLOCKED, 248 ("%s: m %p !M_BLOCKED", __func__, m)); 249 m->m_flags &= ~M_BLOCKED; 250 sb->sb_acc += m->m_len; 251 } 252 253 sb->sb_fnrdy = m; 254 sbready_compress(sb, m0, m); 255 256 return (0); 257 } 258 259 /* 260 * Adjust sockbuf state reflecting allocation of m. 261 */ 262 void 263 sballoc(struct sockbuf *sb, struct mbuf *m) 264 { 265 266 SOCKBUF_LOCK_ASSERT(sb); 267 268 sb->sb_ccc += m->m_len; 269 270 if (sb->sb_fnrdy == NULL) { 271 if (m->m_flags & M_NOTREADY) 272 sb->sb_fnrdy = m; 273 else 274 sb->sb_acc += m->m_len; 275 } else 276 m->m_flags |= M_BLOCKED; 277 278 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 279 sb->sb_ctl += m->m_len; 280 281 sb->sb_mbcnt += MSIZE; 282 283 if (m->m_flags & M_EXT) 284 sb->sb_mbcnt += m->m_ext.ext_size; 285 } 286 287 /* 288 * Adjust sockbuf state reflecting freeing of m. 289 */ 290 void 291 sbfree(struct sockbuf *sb, struct mbuf *m) 292 { 293 294 #if 0 /* XXX: not yet: soclose() call path comes here w/o lock. */ 295 SOCKBUF_LOCK_ASSERT(sb); 296 #endif 297 298 sb->sb_ccc -= m->m_len; 299 300 if (!(m->m_flags & M_NOTAVAIL)) 301 sb->sb_acc -= m->m_len; 302 303 if (m == sb->sb_fnrdy) { 304 struct mbuf *n; 305 306 KASSERT(m->m_flags & M_NOTREADY, 307 ("%s: m %p !M_NOTREADY", __func__, m)); 308 309 n = m->m_next; 310 while (n != NULL && !(n->m_flags & M_NOTREADY)) { 311 n->m_flags &= ~M_BLOCKED; 312 sb->sb_acc += n->m_len; 313 n = n->m_next; 314 } 315 sb->sb_fnrdy = n; 316 } 317 318 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 319 sb->sb_ctl -= m->m_len; 320 321 sb->sb_mbcnt -= MSIZE; 322 if (m->m_flags & M_EXT) 323 sb->sb_mbcnt -= m->m_ext.ext_size; 324 325 if (sb->sb_sndptr == m) { 326 sb->sb_sndptr = NULL; 327 sb->sb_sndptroff = 0; 328 } 329 if (sb->sb_sndptroff != 0) 330 sb->sb_sndptroff -= m->m_len; 331 } 332 333 #ifdef KERN_TLS 334 /* 335 * Similar to sballoc/sbfree but does not adjust state associated with 336 * the sb_mb chain such as sb_fnrdy or sb_sndptr*. Also assumes mbufs 337 * are not ready. 338 */ 339 void 340 sballoc_ktls_rx(struct sockbuf *sb, struct mbuf *m) 341 { 342 343 SOCKBUF_LOCK_ASSERT(sb); 344 345 sb->sb_ccc += m->m_len; 346 sb->sb_tlscc += m->m_len; 347 348 sb->sb_mbcnt += MSIZE; 349 350 if (m->m_flags & M_EXT) 351 sb->sb_mbcnt += m->m_ext.ext_size; 352 } 353 354 void 355 sbfree_ktls_rx(struct sockbuf *sb, struct mbuf *m) 356 { 357 358 #if 0 /* XXX: not yet: soclose() call path comes here w/o lock. */ 359 SOCKBUF_LOCK_ASSERT(sb); 360 #endif 361 362 sb->sb_ccc -= m->m_len; 363 sb->sb_tlscc -= m->m_len; 364 365 sb->sb_mbcnt -= MSIZE; 366 367 if (m->m_flags & M_EXT) 368 sb->sb_mbcnt -= m->m_ext.ext_size; 369 } 370 #endif 371 372 /* 373 * Socantsendmore indicates that no more data will be sent on the socket; it 374 * would normally be applied to a socket when the user informs the system 375 * that no more data is to be sent, by the protocol code (in case 376 * PRU_SHUTDOWN). Socantrcvmore indicates that no more data will be 377 * received, and will normally be applied to the socket by a protocol when it 378 * detects that the peer will send no more data. Data queued for reading in 379 * the socket may yet be read. 380 */ 381 void 382 socantsendmore_locked(struct socket *so) 383 { 384 385 SOCK_SENDBUF_LOCK_ASSERT(so); 386 387 so->so_snd.sb_state |= SBS_CANTSENDMORE; 388 sowwakeup_locked(so); 389 SOCK_SENDBUF_UNLOCK_ASSERT(so); 390 } 391 392 void 393 socantsendmore(struct socket *so) 394 { 395 396 SOCK_SENDBUF_LOCK(so); 397 socantsendmore_locked(so); 398 SOCK_SENDBUF_UNLOCK_ASSERT(so); 399 } 400 401 void 402 socantrcvmore_locked(struct socket *so) 403 { 404 405 SOCK_RECVBUF_LOCK_ASSERT(so); 406 407 so->so_rcv.sb_state |= SBS_CANTRCVMORE; 408 #ifdef KERN_TLS 409 if (so->so_rcv.sb_flags & SB_TLS_RX) 410 ktls_check_rx(&so->so_rcv); 411 #endif 412 sorwakeup_locked(so); 413 SOCK_RECVBUF_UNLOCK_ASSERT(so); 414 } 415 416 void 417 socantrcvmore(struct socket *so) 418 { 419 420 SOCK_RECVBUF_LOCK(so); 421 socantrcvmore_locked(so); 422 SOCK_RECVBUF_UNLOCK_ASSERT(so); 423 } 424 425 void 426 soroverflow_locked(struct socket *so) 427 { 428 429 SOCK_RECVBUF_LOCK_ASSERT(so); 430 431 if (so->so_options & SO_RERROR) { 432 so->so_rerror = ENOBUFS; 433 sorwakeup_locked(so); 434 } else 435 SOCK_RECVBUF_UNLOCK(so); 436 437 SOCK_RECVBUF_UNLOCK_ASSERT(so); 438 } 439 440 void 441 soroverflow(struct socket *so) 442 { 443 444 SOCK_RECVBUF_LOCK(so); 445 soroverflow_locked(so); 446 SOCK_RECVBUF_UNLOCK_ASSERT(so); 447 } 448 449 /* 450 * Wait for data to arrive at/drain from a socket buffer. 451 */ 452 int 453 sbwait(struct socket *so, sb_which which) 454 { 455 struct sockbuf *sb; 456 457 SOCK_BUF_LOCK_ASSERT(so, which); 458 459 sb = sobuf(so, which); 460 sb->sb_flags |= SB_WAIT; 461 return (msleep_sbt(&sb->sb_acc, soeventmtx(so, which), 462 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait", 463 sb->sb_timeo, 0, 0)); 464 } 465 466 /* 467 * Wakeup processes waiting on a socket buffer. Do asynchronous notification 468 * via SIGIO if the socket has the SS_ASYNC flag set. 469 * 470 * Called with the socket buffer lock held; will release the lock by the end 471 * of the function. This allows the caller to acquire the socket buffer lock 472 * while testing for the need for various sorts of wakeup and hold it through 473 * to the point where it's no longer required. We currently hold the lock 474 * through calls out to other subsystems (with the exception of kqueue), and 475 * then release it to avoid lock order issues. It's not clear that's 476 * correct. 477 */ 478 static __always_inline void 479 sowakeup(struct socket *so, const sb_which which) 480 { 481 struct sockbuf *sb; 482 int ret; 483 484 SOCK_BUF_LOCK_ASSERT(so, which); 485 486 sb = sobuf(so, which); 487 selwakeuppri(sb->sb_sel, PSOCK); 488 if (!SEL_WAITING(sb->sb_sel)) 489 sb->sb_flags &= ~SB_SEL; 490 if (sb->sb_flags & SB_WAIT) { 491 sb->sb_flags &= ~SB_WAIT; 492 wakeup(&sb->sb_acc); 493 } 494 KNOTE_LOCKED(&sb->sb_sel->si_note, 0); 495 if (sb->sb_upcall != NULL) { 496 ret = sb->sb_upcall(so, sb->sb_upcallarg, M_NOWAIT); 497 if (ret == SU_ISCONNECTED) { 498 KASSERT(sb == &so->so_rcv, 499 ("SO_SND upcall returned SU_ISCONNECTED")); 500 soupcall_clear(so, SO_RCV); 501 } 502 } else 503 ret = SU_OK; 504 if (sb->sb_flags & SB_AIO) 505 sowakeup_aio(so, which); 506 SOCK_BUF_UNLOCK(so, which); 507 if (ret == SU_ISCONNECTED) 508 soisconnected(so); 509 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 510 pgsigio(&so->so_sigio, SIGIO, 0); 511 SOCK_BUF_UNLOCK_ASSERT(so, which); 512 } 513 514 /* 515 * Do we need to notify the other side when I/O is possible? 516 */ 517 static __always_inline bool 518 sb_notify(const struct sockbuf *sb) 519 { 520 return ((sb->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | 521 SB_UPCALL | SB_AIO | SB_KNOTE)) != 0); 522 } 523 524 void 525 sorwakeup_locked(struct socket *so) 526 { 527 SOCK_RECVBUF_LOCK_ASSERT(so); 528 if (sb_notify(&so->so_rcv)) 529 sowakeup(so, SO_RCV); 530 else 531 SOCK_RECVBUF_UNLOCK(so); 532 } 533 534 void 535 sowwakeup_locked(struct socket *so) 536 { 537 SOCK_SENDBUF_LOCK_ASSERT(so); 538 if (sb_notify(&so->so_snd)) 539 sowakeup(so, SO_SND); 540 else 541 SOCK_SENDBUF_UNLOCK(so); 542 } 543 544 /* 545 * Socket buffer (struct sockbuf) utility routines. 546 * 547 * Each socket contains two socket buffers: one for sending data and one for 548 * receiving data. Each buffer contains a queue of mbufs, information about 549 * the number of mbufs and amount of data in the queue, and other fields 550 * allowing select() statements and notification on data availability to be 551 * implemented. 552 * 553 * Data stored in a socket buffer is maintained as a list of records. Each 554 * record is a list of mbufs chained together with the m_next field. Records 555 * are chained together with the m_nextpkt field. The upper level routine 556 * soreceive() expects the following conventions to be observed when placing 557 * information in the receive buffer: 558 * 559 * 1. If the protocol requires each message be preceded by the sender's name, 560 * then a record containing that name must be present before any 561 * associated data (mbuf's must be of type MT_SONAME). 562 * 2. If the protocol supports the exchange of ``access rights'' (really just 563 * additional data associated with the message), and there are ``rights'' 564 * to be received, then a record containing this data should be present 565 * (mbuf's must be of type MT_RIGHTS). 566 * 3. If a name or rights record exists, then it must be followed by a data 567 * record, perhaps of zero length. 568 * 569 * Before using a new socket structure it is first necessary to reserve 570 * buffer space to the socket, by calling sbreserve(). This should commit 571 * some of the available buffer space in the system buffer pool for the 572 * socket (currently, it does nothing but enforce limits). The space should 573 * be released by calling sbrelease() when the socket is destroyed. 574 */ 575 int 576 soreserve(struct socket *so, u_long sndcc, u_long rcvcc) 577 { 578 struct thread *td = curthread; 579 580 SOCK_SENDBUF_LOCK(so); 581 SOCK_RECVBUF_LOCK(so); 582 if (sbreserve_locked(so, SO_SND, sndcc, td) == 0) 583 goto bad; 584 if (sbreserve_locked(so, SO_RCV, rcvcc, td) == 0) 585 goto bad2; 586 if (so->so_rcv.sb_lowat == 0) 587 so->so_rcv.sb_lowat = 1; 588 if (so->so_snd.sb_lowat == 0) 589 so->so_snd.sb_lowat = MCLBYTES; 590 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 591 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 592 SOCK_RECVBUF_UNLOCK(so); 593 SOCK_SENDBUF_UNLOCK(so); 594 return (0); 595 bad2: 596 sbrelease_locked(so, SO_SND); 597 bad: 598 SOCK_RECVBUF_UNLOCK(so); 599 SOCK_SENDBUF_UNLOCK(so); 600 return (ENOBUFS); 601 } 602 603 static int 604 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 605 { 606 int error = 0; 607 u_long tmp_sb_max = sb_max; 608 609 error = sysctl_handle_long(oidp, &tmp_sb_max, arg2, req); 610 if (error || !req->newptr) 611 return (error); 612 if (tmp_sb_max < MSIZE + MCLBYTES) 613 return (EINVAL); 614 sb_max = tmp_sb_max; 615 sb_max_adj = BUF_MAX_ADJ(sb_max); 616 return (0); 617 } 618 619 /* 620 * Allot mbufs to a sockbuf. Attempt to scale mbmax so that mbcnt doesn't 621 * become limiting if buffering efficiency is near the normal case. 622 */ 623 bool 624 sbreserve_locked_limit(struct socket *so, sb_which which, u_long cc, 625 u_long buf_max, struct thread *td) 626 { 627 struct sockbuf *sb = sobuf(so, which); 628 rlim_t sbsize_limit; 629 630 SOCK_BUF_LOCK_ASSERT(so, which); 631 632 /* 633 * When a thread is passed, we take into account the thread's socket 634 * buffer size limit. The caller will generally pass curthread, but 635 * in the TCP input path, NULL will be passed to indicate that no 636 * appropriate thread resource limits are available. In that case, 637 * we don't apply a process limit. 638 */ 639 if (cc > BUF_MAX_ADJ(buf_max)) 640 return (false); 641 if (td != NULL) { 642 sbsize_limit = lim_cur(td, RLIMIT_SBSIZE); 643 } else 644 sbsize_limit = RLIM_INFINITY; 645 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 646 sbsize_limit)) 647 return (false); 648 sb->sb_mbmax = min(cc * sb_efficiency, buf_max); 649 if (sb->sb_lowat > sb->sb_hiwat) 650 sb->sb_lowat = sb->sb_hiwat; 651 return (true); 652 } 653 654 bool 655 sbreserve_locked(struct socket *so, sb_which which, u_long cc, 656 struct thread *td) 657 { 658 return (sbreserve_locked_limit(so, which, cc, sb_max, td)); 659 } 660 661 int 662 sbsetopt(struct socket *so, struct sockopt *sopt) 663 { 664 struct sockbuf *sb; 665 sb_which wh; 666 short *flags; 667 u_int cc, *hiwat, *lowat; 668 int error, optval; 669 670 error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); 671 if (error != 0) 672 return (error); 673 674 /* 675 * Values < 1 make no sense for any of these options, 676 * so disallow them. 677 */ 678 if (optval < 1) 679 return (EINVAL); 680 cc = optval; 681 682 sb = NULL; 683 SOCK_LOCK(so); 684 if (SOLISTENING(so)) { 685 switch (sopt->sopt_name) { 686 case SO_SNDLOWAT: 687 case SO_SNDBUF: 688 lowat = &so->sol_sbsnd_lowat; 689 hiwat = &so->sol_sbsnd_hiwat; 690 flags = &so->sol_sbsnd_flags; 691 break; 692 case SO_RCVLOWAT: 693 case SO_RCVBUF: 694 lowat = &so->sol_sbrcv_lowat; 695 hiwat = &so->sol_sbrcv_hiwat; 696 flags = &so->sol_sbrcv_flags; 697 break; 698 } 699 } else { 700 switch (sopt->sopt_name) { 701 case SO_SNDLOWAT: 702 case SO_SNDBUF: 703 sb = &so->so_snd; 704 wh = SO_SND; 705 break; 706 case SO_RCVLOWAT: 707 case SO_RCVBUF: 708 sb = &so->so_rcv; 709 wh = SO_RCV; 710 break; 711 } 712 flags = &sb->sb_flags; 713 hiwat = &sb->sb_hiwat; 714 lowat = &sb->sb_lowat; 715 SOCK_BUF_LOCK(so, wh); 716 } 717 718 error = 0; 719 switch (sopt->sopt_name) { 720 case SO_SNDBUF: 721 case SO_RCVBUF: 722 if (SOLISTENING(so)) { 723 if (cc > sb_max_adj) { 724 error = ENOBUFS; 725 break; 726 } 727 *hiwat = cc; 728 if (*lowat > *hiwat) 729 *lowat = *hiwat; 730 } else { 731 if (!sbreserve_locked(so, wh, cc, curthread)) 732 error = ENOBUFS; 733 } 734 if (error == 0) 735 *flags &= ~SB_AUTOSIZE; 736 break; 737 case SO_SNDLOWAT: 738 case SO_RCVLOWAT: 739 /* 740 * Make sure the low-water is never greater than the 741 * high-water. 742 */ 743 *lowat = (cc > *hiwat) ? *hiwat : cc; 744 break; 745 } 746 747 if (!SOLISTENING(so)) 748 SOCK_BUF_UNLOCK(so, wh); 749 SOCK_UNLOCK(so); 750 return (error); 751 } 752 753 /* 754 * Free mbufs held by a socket, and reserved mbuf space. 755 */ 756 static void 757 sbrelease_internal(struct socket *so, sb_which which) 758 { 759 struct sockbuf *sb = sobuf(so, which); 760 761 sbflush_internal(sb); 762 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0, 763 RLIM_INFINITY); 764 sb->sb_mbmax = 0; 765 } 766 767 void 768 sbrelease_locked(struct socket *so, sb_which which) 769 { 770 771 SOCK_BUF_LOCK_ASSERT(so, which); 772 773 sbrelease_internal(so, which); 774 } 775 776 void 777 sbrelease(struct socket *so, sb_which which) 778 { 779 780 SOCK_BUF_LOCK(so, which); 781 sbrelease_locked(so, which); 782 SOCK_BUF_UNLOCK(so, which); 783 } 784 785 void 786 sbdestroy(struct socket *so, sb_which which) 787 { 788 #ifdef KERN_TLS 789 struct sockbuf *sb = sobuf(so, which); 790 791 if (sb->sb_tls_info != NULL) 792 ktls_free(sb->sb_tls_info); 793 sb->sb_tls_info = NULL; 794 #endif 795 sbrelease_internal(so, which); 796 } 797 798 /* 799 * Routines to add and remove data from an mbuf queue. 800 * 801 * The routines sbappend() or sbappendrecord() are normally called to append 802 * new mbufs to a socket buffer, after checking that adequate space is 803 * available, comparing the function sbspace() with the amount of data to be 804 * added. sbappendrecord() differs from sbappend() in that data supplied is 805 * treated as the beginning of a new record. To place a sender's address, 806 * optional access rights, and data in a socket receive buffer, 807 * sbappendaddr() should be used. To place access rights and data in a 808 * socket receive buffer, sbappendrights() should be used. In either case, 809 * the new data begins a new record. Note that unlike sbappend() and 810 * sbappendrecord(), these routines check for the caller that there will be 811 * enough space to store the data. Each fails if there is not enough space, 812 * or if it cannot find mbufs to store additional information in. 813 * 814 * Reliable protocols may use the socket send buffer to hold data awaiting 815 * acknowledgement. Data is normally copied from a socket send buffer in a 816 * protocol with m_copy for output to a peer, and then removing the data from 817 * the socket buffer with sbdrop() or sbdroprecord() when the data is 818 * acknowledged by the peer. 819 */ 820 #ifdef SOCKBUF_DEBUG 821 void 822 sblastrecordchk(struct sockbuf *sb, const char *file, int line) 823 { 824 struct mbuf *m = sb->sb_mb; 825 826 SOCKBUF_LOCK_ASSERT(sb); 827 828 while (m && m->m_nextpkt) 829 m = m->m_nextpkt; 830 831 if (m != sb->sb_lastrecord) { 832 printf("%s: sb_mb %p sb_lastrecord %p last %p\n", 833 __func__, sb->sb_mb, sb->sb_lastrecord, m); 834 printf("packet chain:\n"); 835 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) 836 printf("\t%p\n", m); 837 panic("%s from %s:%u", __func__, file, line); 838 } 839 } 840 841 void 842 sblastmbufchk(struct sockbuf *sb, const char *file, int line) 843 { 844 struct mbuf *m = sb->sb_mb; 845 struct mbuf *n; 846 847 SOCKBUF_LOCK_ASSERT(sb); 848 849 while (m && m->m_nextpkt) 850 m = m->m_nextpkt; 851 852 while (m && m->m_next) 853 m = m->m_next; 854 855 if (m != sb->sb_mbtail) { 856 printf("%s: sb_mb %p sb_mbtail %p last %p\n", 857 __func__, sb->sb_mb, sb->sb_mbtail, m); 858 printf("packet tree:\n"); 859 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) { 860 printf("\t"); 861 for (n = m; n != NULL; n = n->m_next) 862 printf("%p ", n); 863 printf("\n"); 864 } 865 panic("%s from %s:%u", __func__, file, line); 866 } 867 868 #ifdef KERN_TLS 869 m = sb->sb_mtls; 870 while (m && m->m_next) 871 m = m->m_next; 872 873 if (m != sb->sb_mtlstail) { 874 printf("%s: sb_mtls %p sb_mtlstail %p last %p\n", 875 __func__, sb->sb_mtls, sb->sb_mtlstail, m); 876 printf("TLS packet tree:\n"); 877 printf("\t"); 878 for (m = sb->sb_mtls; m != NULL; m = m->m_next) { 879 printf("%p ", m); 880 } 881 printf("\n"); 882 panic("%s from %s:%u", __func__, file, line); 883 } 884 #endif 885 } 886 #endif /* SOCKBUF_DEBUG */ 887 888 #define SBLINKRECORD(sb, m0) do { \ 889 SOCKBUF_LOCK_ASSERT(sb); \ 890 if ((sb)->sb_lastrecord != NULL) \ 891 (sb)->sb_lastrecord->m_nextpkt = (m0); \ 892 else \ 893 (sb)->sb_mb = (m0); \ 894 (sb)->sb_lastrecord = (m0); \ 895 } while (/*CONSTCOND*/0) 896 897 /* 898 * Append mbuf chain m to the last record in the socket buffer sb. The 899 * additional space associated the mbuf chain is recorded in sb. Empty mbufs 900 * are discarded and mbufs are compacted where possible. 901 */ 902 void 903 sbappend_locked(struct sockbuf *sb, struct mbuf *m, int flags) 904 { 905 struct mbuf *n; 906 907 SOCKBUF_LOCK_ASSERT(sb); 908 909 if (m == NULL) 910 return; 911 sbm_clrprotoflags(m, flags); 912 SBLASTRECORDCHK(sb); 913 n = sb->sb_mb; 914 if (n) { 915 while (n->m_nextpkt) 916 n = n->m_nextpkt; 917 do { 918 if (n->m_flags & M_EOR) { 919 sbappendrecord_locked(sb, m); /* XXXXXX!!!! */ 920 return; 921 } 922 } while (n->m_next && (n = n->m_next)); 923 } else { 924 /* 925 * XXX Would like to simply use sb_mbtail here, but 926 * XXX I need to verify that I won't miss an EOR that 927 * XXX way. 928 */ 929 if ((n = sb->sb_lastrecord) != NULL) { 930 do { 931 if (n->m_flags & M_EOR) { 932 sbappendrecord_locked(sb, m); /* XXXXXX!!!! */ 933 return; 934 } 935 } while (n->m_next && (n = n->m_next)); 936 } else { 937 /* 938 * If this is the first record in the socket buffer, 939 * it's also the last record. 940 */ 941 sb->sb_lastrecord = m; 942 } 943 } 944 sbcompress(sb, m, n); 945 SBLASTRECORDCHK(sb); 946 } 947 948 /* 949 * Append mbuf chain m to the last record in the socket buffer sb. The 950 * additional space associated the mbuf chain is recorded in sb. Empty mbufs 951 * are discarded and mbufs are compacted where possible. 952 */ 953 void 954 sbappend(struct sockbuf *sb, struct mbuf *m, int flags) 955 { 956 957 SOCKBUF_LOCK(sb); 958 sbappend_locked(sb, m, flags); 959 SOCKBUF_UNLOCK(sb); 960 } 961 962 #ifdef KERN_TLS 963 /* 964 * Append an mbuf containing encrypted TLS data. The data 965 * is marked M_NOTREADY until it has been decrypted and 966 * stored as a TLS record. 967 */ 968 static void 969 sbappend_ktls_rx(struct sockbuf *sb, struct mbuf *m) 970 { 971 struct ifnet *ifp; 972 struct mbuf *n; 973 int flags; 974 975 ifp = NULL; 976 flags = M_NOTREADY; 977 978 SBLASTMBUFCHK(sb); 979 980 /* Mbuf chain must start with a packet header. */ 981 MPASS((m->m_flags & M_PKTHDR) != 0); 982 983 /* Remove all packet headers and mbuf tags to get a pure data chain. */ 984 for (n = m; n != NULL; n = n->m_next) { 985 if (n->m_flags & M_PKTHDR) { 986 ifp = m->m_pkthdr.leaf_rcvif; 987 if ((n->m_pkthdr.csum_flags & CSUM_TLS_MASK) == 988 CSUM_TLS_DECRYPTED) { 989 /* Mark all mbufs in this packet decrypted. */ 990 flags = M_NOTREADY | M_DECRYPTED; 991 } else { 992 flags = M_NOTREADY; 993 } 994 m_demote_pkthdr(n); 995 } 996 997 n->m_flags &= M_DEMOTEFLAGS; 998 n->m_flags |= flags; 999 1000 MPASS((n->m_flags & M_NOTREADY) != 0); 1001 } 1002 1003 sbcompress_ktls_rx(sb, m, sb->sb_mtlstail); 1004 ktls_check_rx(sb); 1005 1006 /* Check for incoming packet route changes: */ 1007 if (ifp != NULL && sb->sb_tls_info->rx_ifp != NULL && 1008 sb->sb_tls_info->rx_ifp != ifp) 1009 ktls_input_ifp_mismatch(sb, ifp); 1010 } 1011 #endif 1012 1013 /* 1014 * This version of sbappend() should only be used when the caller absolutely 1015 * knows that there will never be more than one record in the socket buffer, 1016 * that is, a stream protocol (such as TCP). 1017 */ 1018 void 1019 sbappendstream_locked(struct sockbuf *sb, struct mbuf *m, int flags) 1020 { 1021 SOCKBUF_LOCK_ASSERT(sb); 1022 1023 KASSERT(m->m_nextpkt == NULL,("sbappendstream 0")); 1024 1025 #ifdef KERN_TLS 1026 /* 1027 * Decrypted TLS records are appended as records via 1028 * sbappendrecord(). TCP passes encrypted TLS records to this 1029 * function which must be scheduled for decryption. 1030 */ 1031 if (sb->sb_flags & SB_TLS_RX) { 1032 sbappend_ktls_rx(sb, m); 1033 return; 1034 } 1035 #endif 1036 1037 KASSERT(sb->sb_mb == sb->sb_lastrecord,("sbappendstream 1")); 1038 1039 SBLASTMBUFCHK(sb); 1040 1041 #ifdef KERN_TLS 1042 if (sb->sb_tls_info != NULL) 1043 ktls_seq(sb, m); 1044 #endif 1045 1046 /* Remove all packet headers and mbuf tags to get a pure data chain. */ 1047 m_demote(m, 1, flags & PRUS_NOTREADY ? M_NOTREADY : 0); 1048 1049 sbcompress(sb, m, sb->sb_mbtail); 1050 1051 sb->sb_lastrecord = sb->sb_mb; 1052 SBLASTRECORDCHK(sb); 1053 } 1054 1055 /* 1056 * This version of sbappend() should only be used when the caller absolutely 1057 * knows that there will never be more than one record in the socket buffer, 1058 * that is, a stream protocol (such as TCP). 1059 */ 1060 void 1061 sbappendstream(struct sockbuf *sb, struct mbuf *m, int flags) 1062 { 1063 1064 SOCKBUF_LOCK(sb); 1065 sbappendstream_locked(sb, m, flags); 1066 SOCKBUF_UNLOCK(sb); 1067 } 1068 1069 #ifdef SOCKBUF_DEBUG 1070 void 1071 sbcheck(struct sockbuf *sb, const char *file, int line) 1072 { 1073 struct mbuf *m, *n, *fnrdy; 1074 u_long acc, ccc, mbcnt; 1075 #ifdef KERN_TLS 1076 u_long tlscc; 1077 #endif 1078 1079 SOCKBUF_LOCK_ASSERT(sb); 1080 1081 acc = ccc = mbcnt = 0; 1082 fnrdy = NULL; 1083 1084 for (m = sb->sb_mb; m; m = n) { 1085 n = m->m_nextpkt; 1086 for (; m; m = m->m_next) { 1087 if (m->m_len == 0) { 1088 printf("sb %p empty mbuf %p\n", sb, m); 1089 goto fail; 1090 } 1091 if ((m->m_flags & M_NOTREADY) && fnrdy == NULL) { 1092 if (m != sb->sb_fnrdy) { 1093 printf("sb %p: fnrdy %p != m %p\n", 1094 sb, sb->sb_fnrdy, m); 1095 goto fail; 1096 } 1097 fnrdy = m; 1098 } 1099 if (fnrdy) { 1100 if (!(m->m_flags & M_NOTAVAIL)) { 1101 printf("sb %p: fnrdy %p, m %p is avail\n", 1102 sb, sb->sb_fnrdy, m); 1103 goto fail; 1104 } 1105 } else 1106 acc += m->m_len; 1107 ccc += m->m_len; 1108 mbcnt += MSIZE; 1109 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 1110 mbcnt += m->m_ext.ext_size; 1111 } 1112 } 1113 #ifdef KERN_TLS 1114 /* 1115 * Account for mbufs "detached" by ktls_detach_record() while 1116 * they are decrypted by ktls_decrypt(). tlsdcc gives a count 1117 * of the detached bytes that are included in ccc. The mbufs 1118 * and clusters are not included in the socket buffer 1119 * accounting. 1120 */ 1121 ccc += sb->sb_tlsdcc; 1122 1123 tlscc = 0; 1124 for (m = sb->sb_mtls; m; m = m->m_next) { 1125 if (m->m_nextpkt != NULL) { 1126 printf("sb %p TLS mbuf %p with nextpkt\n", sb, m); 1127 goto fail; 1128 } 1129 if ((m->m_flags & M_NOTREADY) == 0) { 1130 printf("sb %p TLS mbuf %p ready\n", sb, m); 1131 goto fail; 1132 } 1133 tlscc += m->m_len; 1134 ccc += m->m_len; 1135 mbcnt += MSIZE; 1136 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 1137 mbcnt += m->m_ext.ext_size; 1138 } 1139 1140 if (sb->sb_tlscc != tlscc) { 1141 printf("tlscc %ld/%u dcc %u\n", tlscc, sb->sb_tlscc, 1142 sb->sb_tlsdcc); 1143 goto fail; 1144 } 1145 #endif 1146 if (acc != sb->sb_acc || ccc != sb->sb_ccc || mbcnt != sb->sb_mbcnt) { 1147 printf("acc %ld/%u ccc %ld/%u mbcnt %ld/%u\n", 1148 acc, sb->sb_acc, ccc, sb->sb_ccc, mbcnt, sb->sb_mbcnt); 1149 #ifdef KERN_TLS 1150 printf("tlscc %ld/%u dcc %u\n", tlscc, sb->sb_tlscc, 1151 sb->sb_tlsdcc); 1152 #endif 1153 goto fail; 1154 } 1155 return; 1156 fail: 1157 panic("%s from %s:%u", __func__, file, line); 1158 } 1159 #endif 1160 1161 /* 1162 * As above, except the mbuf chain begins a new record. 1163 */ 1164 void 1165 sbappendrecord_locked(struct sockbuf *sb, struct mbuf *m0) 1166 { 1167 struct mbuf *m; 1168 1169 SOCKBUF_LOCK_ASSERT(sb); 1170 1171 if (m0 == NULL) 1172 return; 1173 m_clrprotoflags(m0); 1174 /* 1175 * Put the first mbuf on the queue. Note this permits zero length 1176 * records. 1177 */ 1178 sballoc(sb, m0); 1179 SBLASTRECORDCHK(sb); 1180 SBLINKRECORD(sb, m0); 1181 sb->sb_mbtail = m0; 1182 m = m0->m_next; 1183 m0->m_next = 0; 1184 if (m && (m0->m_flags & M_EOR)) { 1185 m0->m_flags &= ~M_EOR; 1186 m->m_flags |= M_EOR; 1187 } 1188 /* always call sbcompress() so it can do SBLASTMBUFCHK() */ 1189 sbcompress(sb, m, m0); 1190 } 1191 1192 /* 1193 * As above, except the mbuf chain begins a new record. 1194 */ 1195 void 1196 sbappendrecord(struct sockbuf *sb, struct mbuf *m0) 1197 { 1198 1199 SOCKBUF_LOCK(sb); 1200 sbappendrecord_locked(sb, m0); 1201 SOCKBUF_UNLOCK(sb); 1202 } 1203 1204 /* Helper routine that appends data, control, and address to a sockbuf. */ 1205 static int 1206 sbappendaddr_locked_internal(struct sockbuf *sb, const struct sockaddr *asa, 1207 struct mbuf *m0, struct mbuf *control, struct mbuf *ctrl_last) 1208 { 1209 struct mbuf *m, *n, *nlast; 1210 #if MSIZE <= 256 1211 if (asa->sa_len > MLEN) 1212 return (0); 1213 #endif 1214 m = m_get(M_NOWAIT, MT_SONAME); 1215 if (m == NULL) 1216 return (0); 1217 m->m_len = asa->sa_len; 1218 bcopy(asa, mtod(m, caddr_t), asa->sa_len); 1219 if (m0) { 1220 M_ASSERT_NO_SND_TAG(m0); 1221 m_clrprotoflags(m0); 1222 m_tag_delete_chain(m0, NULL); 1223 /* 1224 * Clear some persistent info from pkthdr. 1225 * We don't use m_demote(), because some netgraph consumers 1226 * expect M_PKTHDR presence. 1227 */ 1228 m0->m_pkthdr.rcvif = NULL; 1229 m0->m_pkthdr.flowid = 0; 1230 m0->m_pkthdr.csum_flags = 0; 1231 m0->m_pkthdr.fibnum = 0; 1232 m0->m_pkthdr.rsstype = 0; 1233 } 1234 if (ctrl_last) 1235 ctrl_last->m_next = m0; /* concatenate data to control */ 1236 else 1237 control = m0; 1238 m->m_next = control; 1239 for (n = m; n->m_next != NULL; n = n->m_next) 1240 sballoc(sb, n); 1241 sballoc(sb, n); 1242 nlast = n; 1243 SBLINKRECORD(sb, m); 1244 1245 sb->sb_mbtail = nlast; 1246 SBLASTMBUFCHK(sb); 1247 1248 SBLASTRECORDCHK(sb); 1249 return (1); 1250 } 1251 1252 /* 1253 * Append address and data, and optionally, control (ancillary) data to the 1254 * receive queue of a socket. If present, m0 must include a packet header 1255 * with total length. Returns 0 if no space in sockbuf or insufficient 1256 * mbufs. 1257 */ 1258 int 1259 sbappendaddr_locked(struct sockbuf *sb, const struct sockaddr *asa, 1260 struct mbuf *m0, struct mbuf *control) 1261 { 1262 struct mbuf *ctrl_last; 1263 int space = asa->sa_len; 1264 1265 SOCKBUF_LOCK_ASSERT(sb); 1266 1267 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 1268 panic("sbappendaddr_locked"); 1269 if (m0) 1270 space += m0->m_pkthdr.len; 1271 space += m_length(control, &ctrl_last); 1272 1273 if (space > sbspace(sb)) 1274 return (0); 1275 return (sbappendaddr_locked_internal(sb, asa, m0, control, ctrl_last)); 1276 } 1277 1278 /* 1279 * Append address and data, and optionally, control (ancillary) data to the 1280 * receive queue of a socket. If present, m0 must include a packet header 1281 * with total length. Returns 0 if insufficient mbufs. Does not validate space 1282 * on the receiving sockbuf. 1283 */ 1284 int 1285 sbappendaddr_nospacecheck_locked(struct sockbuf *sb, const struct sockaddr *asa, 1286 struct mbuf *m0, struct mbuf *control) 1287 { 1288 struct mbuf *ctrl_last; 1289 1290 SOCKBUF_LOCK_ASSERT(sb); 1291 1292 ctrl_last = (control == NULL) ? NULL : m_last(control); 1293 return (sbappendaddr_locked_internal(sb, asa, m0, control, ctrl_last)); 1294 } 1295 1296 /* 1297 * Append address and data, and optionally, control (ancillary) data to the 1298 * receive queue of a socket. If present, m0 must include a packet header 1299 * with total length. Returns 0 if no space in sockbuf or insufficient 1300 * mbufs. 1301 */ 1302 int 1303 sbappendaddr(struct sockbuf *sb, const struct sockaddr *asa, 1304 struct mbuf *m0, struct mbuf *control) 1305 { 1306 int retval; 1307 1308 SOCKBUF_LOCK(sb); 1309 retval = sbappendaddr_locked(sb, asa, m0, control); 1310 SOCKBUF_UNLOCK(sb); 1311 return (retval); 1312 } 1313 1314 void 1315 sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0, 1316 struct mbuf *control, int flags) 1317 { 1318 struct mbuf *m, *mlast; 1319 1320 sbm_clrprotoflags(m0, flags); 1321 m_last(control)->m_next = m0; 1322 1323 SBLASTRECORDCHK(sb); 1324 1325 for (m = control; m->m_next; m = m->m_next) 1326 sballoc(sb, m); 1327 sballoc(sb, m); 1328 mlast = m; 1329 SBLINKRECORD(sb, control); 1330 1331 sb->sb_mbtail = mlast; 1332 SBLASTMBUFCHK(sb); 1333 1334 SBLASTRECORDCHK(sb); 1335 } 1336 1337 void 1338 sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control, 1339 int flags) 1340 { 1341 1342 SOCKBUF_LOCK(sb); 1343 sbappendcontrol_locked(sb, m0, control, flags); 1344 SOCKBUF_UNLOCK(sb); 1345 } 1346 1347 /* 1348 * Append the data in mbuf chain (m) into the socket buffer sb following mbuf 1349 * (n). If (n) is NULL, the buffer is presumed empty. 1350 * 1351 * When the data is compressed, mbufs in the chain may be handled in one of 1352 * three ways: 1353 * 1354 * (1) The mbuf may simply be dropped, if it contributes nothing (no data, no 1355 * record boundary, and no change in data type). 1356 * 1357 * (2) The mbuf may be coalesced -- i.e., data in the mbuf may be copied into 1358 * an mbuf already in the socket buffer. This can occur if an 1359 * appropriate mbuf exists, there is room, both mbufs are not marked as 1360 * not ready, and no merging of data types will occur. 1361 * 1362 * (3) The mbuf may be appended to the end of the existing mbuf chain. 1363 * 1364 * If any of the new mbufs is marked as M_EOR, mark the last mbuf appended as 1365 * end-of-record. 1366 */ 1367 void 1368 sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n) 1369 { 1370 int eor = 0; 1371 struct mbuf *o; 1372 1373 SOCKBUF_LOCK_ASSERT(sb); 1374 1375 while (m) { 1376 eor |= m->m_flags & M_EOR; 1377 if (m->m_len == 0 && 1378 (eor == 0 || 1379 (((o = m->m_next) || (o = n)) && 1380 o->m_type == m->m_type))) { 1381 if (sb->sb_lastrecord == m) 1382 sb->sb_lastrecord = m->m_next; 1383 m = m_free(m); 1384 continue; 1385 } 1386 if (n && (n->m_flags & M_EOR) == 0 && 1387 M_WRITABLE(n) && 1388 ((sb->sb_flags & SB_NOCOALESCE) == 0) && 1389 !(m->m_flags & M_NOTREADY) && 1390 !(n->m_flags & (M_NOTREADY | M_EXTPG)) && 1391 !mbuf_has_tls_session(m) && 1392 !mbuf_has_tls_session(n) && 1393 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 1394 m->m_len <= M_TRAILINGSPACE(n) && 1395 n->m_type == m->m_type) { 1396 m_copydata(m, 0, m->m_len, mtodo(n, n->m_len)); 1397 n->m_len += m->m_len; 1398 sb->sb_ccc += m->m_len; 1399 if (sb->sb_fnrdy == NULL) 1400 sb->sb_acc += m->m_len; 1401 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 1402 /* XXX: Probably don't need.*/ 1403 sb->sb_ctl += m->m_len; 1404 m = m_free(m); 1405 continue; 1406 } 1407 if (m->m_len <= MLEN && (m->m_flags & M_EXTPG) && 1408 (m->m_flags & M_NOTREADY) == 0 && 1409 !mbuf_has_tls_session(m)) 1410 (void)mb_unmapped_compress(m); 1411 if (n) 1412 n->m_next = m; 1413 else 1414 sb->sb_mb = m; 1415 sb->sb_mbtail = m; 1416 sballoc(sb, m); 1417 n = m; 1418 m->m_flags &= ~M_EOR; 1419 m = m->m_next; 1420 n->m_next = 0; 1421 } 1422 if (eor) { 1423 KASSERT(n != NULL, ("sbcompress: eor && n == NULL")); 1424 n->m_flags |= eor; 1425 } 1426 SBLASTMBUFCHK(sb); 1427 } 1428 1429 #ifdef KERN_TLS 1430 /* 1431 * A version of sbcompress() for encrypted TLS RX mbufs. These mbufs 1432 * are appended to the 'sb_mtls' chain instead of 'sb_mb' and are also 1433 * a bit simpler (no EOR markers, always MT_DATA, etc.). 1434 */ 1435 static void 1436 sbcompress_ktls_rx(struct sockbuf *sb, struct mbuf *m, struct mbuf *n) 1437 { 1438 1439 SOCKBUF_LOCK_ASSERT(sb); 1440 1441 while (m) { 1442 KASSERT((m->m_flags & M_EOR) == 0, 1443 ("TLS RX mbuf %p with EOR", m)); 1444 KASSERT(m->m_type == MT_DATA, 1445 ("TLS RX mbuf %p is not MT_DATA", m)); 1446 KASSERT((m->m_flags & M_NOTREADY) != 0, 1447 ("TLS RX mbuf %p ready", m)); 1448 KASSERT((m->m_flags & M_EXTPG) == 0, 1449 ("TLS RX mbuf %p unmapped", m)); 1450 1451 if (m->m_len == 0) { 1452 m = m_free(m); 1453 continue; 1454 } 1455 1456 /* 1457 * Even though both 'n' and 'm' are NOTREADY, it's ok 1458 * to coalesce the data. 1459 */ 1460 if (n && 1461 M_WRITABLE(n) && 1462 ((sb->sb_flags & SB_NOCOALESCE) == 0) && 1463 !((m->m_flags ^ n->m_flags) & M_DECRYPTED) && 1464 !(n->m_flags & M_EXTPG) && 1465 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 1466 m->m_len <= M_TRAILINGSPACE(n)) { 1467 m_copydata(m, 0, m->m_len, mtodo(n, n->m_len)); 1468 n->m_len += m->m_len; 1469 sb->sb_ccc += m->m_len; 1470 sb->sb_tlscc += m->m_len; 1471 m = m_free(m); 1472 continue; 1473 } 1474 if (n) 1475 n->m_next = m; 1476 else 1477 sb->sb_mtls = m; 1478 sb->sb_mtlstail = m; 1479 sballoc_ktls_rx(sb, m); 1480 n = m; 1481 m = m->m_next; 1482 n->m_next = NULL; 1483 } 1484 SBLASTMBUFCHK(sb); 1485 } 1486 #endif 1487 1488 /* 1489 * Free all mbufs in a sockbuf. Check that all resources are reclaimed. 1490 */ 1491 static void 1492 sbflush_internal(struct sockbuf *sb) 1493 { 1494 1495 while (sb->sb_mbcnt || sb->sb_tlsdcc) { 1496 /* 1497 * Don't call sbcut(sb, 0) if the leading mbuf is non-empty: 1498 * we would loop forever. Panic instead. 1499 */ 1500 if (sb->sb_ccc == 0 && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 1501 break; 1502 m_freem(sbcut_internal(sb, (int)sb->sb_ccc)); 1503 } 1504 KASSERT(sb->sb_ccc == 0 && sb->sb_mb == 0 && sb->sb_mbcnt == 0, 1505 ("%s: ccc %u mb %p mbcnt %u", __func__, 1506 sb->sb_ccc, (void *)sb->sb_mb, sb->sb_mbcnt)); 1507 } 1508 1509 void 1510 sbflush_locked(struct sockbuf *sb) 1511 { 1512 1513 SOCKBUF_LOCK_ASSERT(sb); 1514 sbflush_internal(sb); 1515 } 1516 1517 void 1518 sbflush(struct sockbuf *sb) 1519 { 1520 1521 SOCKBUF_LOCK(sb); 1522 sbflush_locked(sb); 1523 SOCKBUF_UNLOCK(sb); 1524 } 1525 1526 /* 1527 * Cut data from (the front of) a sockbuf. 1528 */ 1529 static struct mbuf * 1530 sbcut_internal(struct sockbuf *sb, int len) 1531 { 1532 struct mbuf *m, *next, *mfree; 1533 bool is_tls; 1534 1535 KASSERT(len >= 0, ("%s: len is %d but it is supposed to be >= 0", 1536 __func__, len)); 1537 KASSERT(len <= sb->sb_ccc, ("%s: len: %d is > ccc: %u", 1538 __func__, len, sb->sb_ccc)); 1539 1540 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 1541 is_tls = false; 1542 mfree = NULL; 1543 1544 while (len > 0) { 1545 if (m == NULL) { 1546 #ifdef KERN_TLS 1547 if (next == NULL && !is_tls) { 1548 if (sb->sb_tlsdcc != 0) { 1549 MPASS(len >= sb->sb_tlsdcc); 1550 len -= sb->sb_tlsdcc; 1551 sb->sb_ccc -= sb->sb_tlsdcc; 1552 sb->sb_tlsdcc = 0; 1553 if (len == 0) 1554 break; 1555 } 1556 next = sb->sb_mtls; 1557 is_tls = true; 1558 } 1559 #endif 1560 KASSERT(next, ("%s: no next, len %d", __func__, len)); 1561 m = next; 1562 next = m->m_nextpkt; 1563 } 1564 if (m->m_len > len) { 1565 KASSERT(!(m->m_flags & M_NOTAVAIL), 1566 ("%s: m %p M_NOTAVAIL", __func__, m)); 1567 m->m_len -= len; 1568 m->m_data += len; 1569 sb->sb_ccc -= len; 1570 sb->sb_acc -= len; 1571 if (sb->sb_sndptroff != 0) 1572 sb->sb_sndptroff -= len; 1573 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 1574 sb->sb_ctl -= len; 1575 break; 1576 } 1577 len -= m->m_len; 1578 #ifdef KERN_TLS 1579 if (is_tls) 1580 sbfree_ktls_rx(sb, m); 1581 else 1582 #endif 1583 sbfree(sb, m); 1584 /* 1585 * Do not put M_NOTREADY buffers to the free list, they 1586 * are referenced from outside. 1587 */ 1588 if (m->m_flags & M_NOTREADY && !is_tls) 1589 m = m->m_next; 1590 else { 1591 struct mbuf *n; 1592 1593 n = m->m_next; 1594 m->m_next = mfree; 1595 mfree = m; 1596 m = n; 1597 } 1598 } 1599 /* 1600 * Free any zero-length mbufs from the buffer. 1601 * For SOCK_DGRAM sockets such mbufs represent empty records. 1602 * XXX: For SOCK_STREAM sockets such mbufs can appear in the buffer, 1603 * when sosend_generic() needs to send only control data. 1604 */ 1605 while (m && m->m_len == 0) { 1606 struct mbuf *n; 1607 1608 sbfree(sb, m); 1609 n = m->m_next; 1610 m->m_next = mfree; 1611 mfree = m; 1612 m = n; 1613 } 1614 #ifdef KERN_TLS 1615 if (is_tls) { 1616 sb->sb_mb = NULL; 1617 sb->sb_mtls = m; 1618 if (m == NULL) 1619 sb->sb_mtlstail = NULL; 1620 } else 1621 #endif 1622 if (m) { 1623 sb->sb_mb = m; 1624 m->m_nextpkt = next; 1625 } else 1626 sb->sb_mb = next; 1627 /* 1628 * First part is an inline SB_EMPTY_FIXUP(). Second part makes sure 1629 * sb_lastrecord is up-to-date if we dropped part of the last record. 1630 */ 1631 m = sb->sb_mb; 1632 if (m == NULL) { 1633 sb->sb_mbtail = NULL; 1634 sb->sb_lastrecord = NULL; 1635 } else if (m->m_nextpkt == NULL) { 1636 sb->sb_lastrecord = m; 1637 } 1638 1639 return (mfree); 1640 } 1641 1642 /* 1643 * Drop data from (the front of) a sockbuf. 1644 */ 1645 void 1646 sbdrop_locked(struct sockbuf *sb, int len) 1647 { 1648 1649 SOCKBUF_LOCK_ASSERT(sb); 1650 m_freem(sbcut_internal(sb, len)); 1651 } 1652 1653 /* 1654 * Drop data from (the front of) a sockbuf, 1655 * and return it to caller. 1656 */ 1657 struct mbuf * 1658 sbcut_locked(struct sockbuf *sb, int len) 1659 { 1660 1661 SOCKBUF_LOCK_ASSERT(sb); 1662 return (sbcut_internal(sb, len)); 1663 } 1664 1665 void 1666 sbdrop(struct sockbuf *sb, int len) 1667 { 1668 struct mbuf *mfree; 1669 1670 SOCKBUF_LOCK(sb); 1671 mfree = sbcut_internal(sb, len); 1672 SOCKBUF_UNLOCK(sb); 1673 1674 m_freem(mfree); 1675 } 1676 1677 struct mbuf * 1678 sbsndptr_noadv(struct sockbuf *sb, uint32_t off, uint32_t *moff) 1679 { 1680 struct mbuf *m; 1681 1682 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__)); 1683 if (sb->sb_sndptr == NULL || sb->sb_sndptroff > off) { 1684 *moff = off; 1685 if (sb->sb_sndptr == NULL) { 1686 sb->sb_sndptr = sb->sb_mb; 1687 sb->sb_sndptroff = 0; 1688 } 1689 return (sb->sb_mb); 1690 } else { 1691 m = sb->sb_sndptr; 1692 off -= sb->sb_sndptroff; 1693 } 1694 *moff = off; 1695 return (m); 1696 } 1697 1698 void 1699 sbsndptr_adv(struct sockbuf *sb, struct mbuf *mb, uint32_t len) 1700 { 1701 /* 1702 * A small copy was done, advance forward the sb_sbsndptr to cover 1703 * it. 1704 */ 1705 struct mbuf *m; 1706 1707 if (mb != sb->sb_sndptr) { 1708 /* Did not copyout at the same mbuf */ 1709 return; 1710 } 1711 m = mb; 1712 while (m && (len > 0)) { 1713 if (len >= m->m_len) { 1714 len -= m->m_len; 1715 if (m->m_next) { 1716 sb->sb_sndptroff += m->m_len; 1717 sb->sb_sndptr = m->m_next; 1718 } 1719 m = m->m_next; 1720 } else { 1721 len = 0; 1722 } 1723 } 1724 } 1725 1726 /* 1727 * Return the first mbuf and the mbuf data offset for the provided 1728 * send offset without changing the "sb_sndptroff" field. 1729 */ 1730 struct mbuf * 1731 sbsndmbuf(struct sockbuf *sb, u_int off, u_int *moff) 1732 { 1733 struct mbuf *m; 1734 1735 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__)); 1736 1737 /* 1738 * If the "off" is below the stored offset, which happens on 1739 * retransmits, just use "sb_mb": 1740 */ 1741 if (sb->sb_sndptr == NULL || sb->sb_sndptroff > off) { 1742 m = sb->sb_mb; 1743 } else { 1744 m = sb->sb_sndptr; 1745 off -= sb->sb_sndptroff; 1746 } 1747 while (off > 0 && m != NULL) { 1748 if (off < m->m_len) 1749 break; 1750 off -= m->m_len; 1751 m = m->m_next; 1752 } 1753 *moff = off; 1754 return (m); 1755 } 1756 1757 /* 1758 * Drop a record off the front of a sockbuf and move the next record to the 1759 * front. 1760 */ 1761 void 1762 sbdroprecord_locked(struct sockbuf *sb) 1763 { 1764 struct mbuf *m; 1765 1766 SOCKBUF_LOCK_ASSERT(sb); 1767 1768 m = sb->sb_mb; 1769 if (m) { 1770 sb->sb_mb = m->m_nextpkt; 1771 do { 1772 sbfree(sb, m); 1773 m = m_free(m); 1774 } while (m); 1775 } 1776 SB_EMPTY_FIXUP(sb); 1777 } 1778 1779 /* 1780 * Drop a record off the front of a sockbuf and move the next record to the 1781 * front. 1782 */ 1783 void 1784 sbdroprecord(struct sockbuf *sb) 1785 { 1786 1787 SOCKBUF_LOCK(sb); 1788 sbdroprecord_locked(sb); 1789 SOCKBUF_UNLOCK(sb); 1790 } 1791 1792 /* 1793 * Create a "control" mbuf containing the specified data with the specified 1794 * type for presentation on a socket buffer. 1795 */ 1796 struct mbuf * 1797 sbcreatecontrol(const void *p, u_int size, int type, int level, int wait) 1798 { 1799 struct cmsghdr *cp; 1800 struct mbuf *m; 1801 1802 MBUF_CHECKSLEEP(wait); 1803 1804 if (wait == M_NOWAIT) { 1805 if (CMSG_SPACE(size) > MCLBYTES) 1806 return (NULL); 1807 } else 1808 KASSERT(CMSG_SPACE(size) <= MCLBYTES, 1809 ("%s: passed CMSG_SPACE(%u) > MCLBYTES", __func__, size)); 1810 1811 if (CMSG_SPACE(size) > MLEN) 1812 m = m_getcl(wait, MT_CONTROL, 0); 1813 else 1814 m = m_get(wait, MT_CONTROL); 1815 if (m == NULL) 1816 return (NULL); 1817 1818 KASSERT(CMSG_SPACE(size) <= M_TRAILINGSPACE(m), 1819 ("sbcreatecontrol: short mbuf")); 1820 /* 1821 * Don't leave the padding between the msg header and the 1822 * cmsg data and the padding after the cmsg data un-initialized. 1823 */ 1824 cp = mtod(m, struct cmsghdr *); 1825 bzero(cp, CMSG_SPACE(size)); 1826 if (p != NULL) 1827 (void)memcpy(CMSG_DATA(cp), p, size); 1828 m->m_len = CMSG_SPACE(size); 1829 cp->cmsg_len = CMSG_LEN(size); 1830 cp->cmsg_level = level; 1831 cp->cmsg_type = type; 1832 return (m); 1833 } 1834 1835 /* 1836 * This does the same for socket buffers that sotoxsocket does for sockets: 1837 * generate an user-format data structure describing the socket buffer. Note 1838 * that the xsockbuf structure, since it is always embedded in a socket, does 1839 * not include a self pointer nor a length. We make this entry point public 1840 * in case some other mechanism needs it. 1841 */ 1842 void 1843 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 1844 { 1845 1846 xsb->sb_cc = sb->sb_ccc; 1847 xsb->sb_hiwat = sb->sb_hiwat; 1848 xsb->sb_mbcnt = sb->sb_mbcnt; 1849 xsb->sb_mbmax = sb->sb_mbmax; 1850 xsb->sb_lowat = sb->sb_lowat; 1851 xsb->sb_flags = sb->sb_flags; 1852 xsb->sb_timeo = sb->sb_timeo; 1853 } 1854 1855 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 1856 static int dummy; 1857 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW | CTLFLAG_SKIP, &dummy, 0, ""); 1858 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, 1859 CTLTYPE_ULONG | CTLFLAG_RW | CTLFLAG_MPSAFE, &sb_max, 0, 1860 sysctl_handle_sb_max, "LU", 1861 "Maximum socket buffer size"); 1862 SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1863 &sb_efficiency, 0, "Socket buffer size waste factor");
Cache object: 3650f998b29d92ec5ca66192e22497d1
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