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 32 #include <sys/cdefs.h> 33 #include "opt_kern_tls.h" 34 #include "opt_param.h" 35 36 #include <sys/param.h> 37 #include <sys/aio.h> /* for aio_swake proto */ 38 #include <sys/kernel.h> 39 #include <sys/ktls.h> 40 #include <sys/lock.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/msan.h> 44 #include <sys/mutex.h> 45 #include <sys/proc.h> 46 #include <sys/protosw.h> 47 #include <sys/resourcevar.h> 48 #include <sys/signalvar.h> 49 #include <sys/socket.h> 50 #include <sys/socketvar.h> 51 #include <sys/sx.h> 52 #include <sys/sysctl.h> 53 54 #include <netinet/in.h> 55 56 /* 57 * Function pointer set by the AIO routines so that the socket buffer code 58 * can call back into the AIO module if it is loaded. 59 */ 60 void (*aio_swake)(struct socket *, struct sockbuf *); 61 62 /* 63 * Primitive routines for operating on socket buffers 64 */ 65 66 #define BUF_MAX_ADJ(_sz) (((u_quad_t)(_sz)) * MCLBYTES / (MSIZE + MCLBYTES)) 67 68 u_long sb_max = SB_MAX; 69 u_long sb_max_adj = BUF_MAX_ADJ(SB_MAX); 70 71 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 72 73 #ifdef KERN_TLS 74 static void sbcompress_ktls_rx(struct sockbuf *sb, struct mbuf *m, 75 struct mbuf *n); 76 #endif 77 static struct mbuf *sbcut_internal(struct sockbuf *sb, int len); 78 static void sbflush_internal(struct sockbuf *sb); 79 80 /* 81 * Our own version of m_clrprotoflags(), that can preserve M_NOTREADY. 82 */ 83 static void 84 sbm_clrprotoflags(struct mbuf *m, int flags) 85 { 86 int mask; 87 88 mask = ~M_PROTOFLAGS; 89 if (flags & PRUS_NOTREADY) 90 mask |= M_NOTREADY; 91 while (m) { 92 m->m_flags &= mask; 93 m = m->m_next; 94 } 95 } 96 97 /* 98 * Compress M_NOTREADY mbufs after they have been readied by sbready(). 99 * 100 * sbcompress() skips M_NOTREADY mbufs since the data is not available to 101 * be copied at the time of sbcompress(). This function combines small 102 * mbufs similar to sbcompress() once mbufs are ready. 'm0' is the first 103 * mbuf sbready() marked ready, and 'end' is the first mbuf still not 104 * ready. 105 */ 106 static void 107 sbready_compress(struct sockbuf *sb, struct mbuf *m0, struct mbuf *end) 108 { 109 struct mbuf *m, *n; 110 int ext_size; 111 112 SOCKBUF_LOCK_ASSERT(sb); 113 114 if ((sb->sb_flags & SB_NOCOALESCE) != 0) 115 return; 116 117 for (m = m0; m != end; m = m->m_next) { 118 MPASS((m->m_flags & M_NOTREADY) == 0); 119 /* 120 * NB: In sbcompress(), 'n' is the last mbuf in the 121 * socket buffer and 'm' is the new mbuf being copied 122 * into the trailing space of 'n'. Here, the roles 123 * are reversed and 'n' is the next mbuf after 'm' 124 * that is being copied into the trailing space of 125 * 'm'. 126 */ 127 n = m->m_next; 128 #ifdef KERN_TLS 129 /* Try to coalesce adjacent ktls mbuf hdr/trailers. */ 130 if ((n != NULL) && (n != end) && (m->m_flags & M_EOR) == 0 && 131 (m->m_flags & M_EXTPG) && 132 (n->m_flags & M_EXTPG) && 133 !mbuf_has_tls_session(m) && 134 !mbuf_has_tls_session(n)) { 135 int hdr_len, trail_len; 136 137 hdr_len = n->m_epg_hdrlen; 138 trail_len = m->m_epg_trllen; 139 if (trail_len != 0 && hdr_len != 0 && 140 trail_len + hdr_len <= MBUF_PEXT_TRAIL_LEN) { 141 /* copy n's header to m's trailer */ 142 memcpy(&m->m_epg_trail[trail_len], 143 n->m_epg_hdr, hdr_len); 144 m->m_epg_trllen += hdr_len; 145 m->m_len += hdr_len; 146 n->m_epg_hdrlen = 0; 147 n->m_len -= hdr_len; 148 } 149 } 150 #endif 151 152 /* Compress small unmapped mbufs into plain mbufs. */ 153 if ((m->m_flags & M_EXTPG) && m->m_len <= MLEN && 154 !mbuf_has_tls_session(m)) { 155 ext_size = m->m_ext.ext_size; 156 if (mb_unmapped_compress(m) == 0) 157 sb->sb_mbcnt -= ext_size; 158 } 159 160 while ((n != NULL) && (n != end) && (m->m_flags & M_EOR) == 0 && 161 M_WRITABLE(m) && 162 (m->m_flags & M_EXTPG) == 0 && 163 !mbuf_has_tls_session(n) && 164 !mbuf_has_tls_session(m) && 165 n->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 166 n->m_len <= M_TRAILINGSPACE(m) && 167 m->m_type == n->m_type) { 168 KASSERT(sb->sb_lastrecord != n, 169 ("%s: merging start of record (%p) into previous mbuf (%p)", 170 __func__, n, m)); 171 m_copydata(n, 0, n->m_len, mtodo(m, m->m_len)); 172 m->m_len += n->m_len; 173 m->m_next = n->m_next; 174 m->m_flags |= n->m_flags & M_EOR; 175 if (sb->sb_mbtail == n) 176 sb->sb_mbtail = m; 177 178 sb->sb_mbcnt -= MSIZE; 179 if (n->m_flags & M_EXT) 180 sb->sb_mbcnt -= n->m_ext.ext_size; 181 m_free(n); 182 n = m->m_next; 183 } 184 } 185 SBLASTRECORDCHK(sb); 186 SBLASTMBUFCHK(sb); 187 } 188 189 /* 190 * Mark ready "count" units of I/O starting with "m". Most mbufs 191 * count as a single unit of I/O except for M_EXTPG mbufs which 192 * are backed by multiple pages. 193 */ 194 int 195 sbready(struct sockbuf *sb, struct mbuf *m0, int count) 196 { 197 struct mbuf *m; 198 u_int blocker; 199 200 SOCKBUF_LOCK_ASSERT(sb); 201 KASSERT(sb->sb_fnrdy != NULL, ("%s: sb %p NULL fnrdy", __func__, sb)); 202 KASSERT(count > 0, ("%s: invalid count %d", __func__, count)); 203 204 m = m0; 205 blocker = (sb->sb_fnrdy == m) ? M_BLOCKED : 0; 206 207 while (count > 0) { 208 KASSERT(m->m_flags & M_NOTREADY, 209 ("%s: m %p !M_NOTREADY", __func__, m)); 210 if ((m->m_flags & M_EXTPG) != 0 && m->m_epg_npgs != 0) { 211 if (count < m->m_epg_nrdy) { 212 m->m_epg_nrdy -= count; 213 count = 0; 214 break; 215 } 216 count -= m->m_epg_nrdy; 217 m->m_epg_nrdy = 0; 218 } else 219 count--; 220 221 m->m_flags &= ~(M_NOTREADY | blocker); 222 if (blocker) 223 sb->sb_acc += m->m_len; 224 m = m->m_next; 225 } 226 227 /* 228 * If the first mbuf is still not fully ready because only 229 * some of its backing pages were readied, no further progress 230 * can be made. 231 */ 232 if (m0 == m) { 233 MPASS(m->m_flags & M_NOTREADY); 234 return (EINPROGRESS); 235 } 236 237 if (!blocker) { 238 sbready_compress(sb, m0, m); 239 return (EINPROGRESS); 240 } 241 242 /* This one was blocking all the queue. */ 243 for (; m && (m->m_flags & M_NOTREADY) == 0; m = m->m_next) { 244 KASSERT(m->m_flags & M_BLOCKED, 245 ("%s: m %p !M_BLOCKED", __func__, m)); 246 m->m_flags &= ~M_BLOCKED; 247 sb->sb_acc += m->m_len; 248 } 249 250 sb->sb_fnrdy = m; 251 sbready_compress(sb, m0, m); 252 253 return (0); 254 } 255 256 /* 257 * Adjust sockbuf state reflecting allocation of m. 258 */ 259 void 260 sballoc(struct sockbuf *sb, struct mbuf *m) 261 { 262 263 SOCKBUF_LOCK_ASSERT(sb); 264 265 sb->sb_ccc += m->m_len; 266 267 if (sb->sb_fnrdy == NULL) { 268 if (m->m_flags & M_NOTREADY) 269 sb->sb_fnrdy = m; 270 else 271 sb->sb_acc += m->m_len; 272 } else 273 m->m_flags |= M_BLOCKED; 274 275 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 276 sb->sb_ctl += m->m_len; 277 278 sb->sb_mbcnt += MSIZE; 279 280 if (m->m_flags & M_EXT) 281 sb->sb_mbcnt += m->m_ext.ext_size; 282 } 283 284 /* 285 * Adjust sockbuf state reflecting freeing of m. 286 */ 287 void 288 sbfree(struct sockbuf *sb, struct mbuf *m) 289 { 290 291 #if 0 /* XXX: not yet: soclose() call path comes here w/o lock. */ 292 SOCKBUF_LOCK_ASSERT(sb); 293 #endif 294 295 sb->sb_ccc -= m->m_len; 296 297 if (!(m->m_flags & M_NOTAVAIL)) 298 sb->sb_acc -= m->m_len; 299 300 if (m == sb->sb_fnrdy) { 301 struct mbuf *n; 302 303 KASSERT(m->m_flags & M_NOTREADY, 304 ("%s: m %p !M_NOTREADY", __func__, m)); 305 306 n = m->m_next; 307 while (n != NULL && !(n->m_flags & M_NOTREADY)) { 308 n->m_flags &= ~M_BLOCKED; 309 sb->sb_acc += n->m_len; 310 n = n->m_next; 311 } 312 sb->sb_fnrdy = n; 313 } 314 315 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 316 sb->sb_ctl -= m->m_len; 317 318 sb->sb_mbcnt -= MSIZE; 319 if (m->m_flags & M_EXT) 320 sb->sb_mbcnt -= m->m_ext.ext_size; 321 322 if (sb->sb_sndptr == m) { 323 sb->sb_sndptr = NULL; 324 sb->sb_sndptroff = 0; 325 } 326 if (sb->sb_sndptroff != 0) 327 sb->sb_sndptroff -= m->m_len; 328 } 329 330 #ifdef KERN_TLS 331 /* 332 * Similar to sballoc/sbfree but does not adjust state associated with 333 * the sb_mb chain such as sb_fnrdy or sb_sndptr*. Also assumes mbufs 334 * are not ready. 335 */ 336 void 337 sballoc_ktls_rx(struct sockbuf *sb, struct mbuf *m) 338 { 339 340 SOCKBUF_LOCK_ASSERT(sb); 341 342 sb->sb_ccc += m->m_len; 343 sb->sb_tlscc += m->m_len; 344 345 sb->sb_mbcnt += MSIZE; 346 347 if (m->m_flags & M_EXT) 348 sb->sb_mbcnt += m->m_ext.ext_size; 349 } 350 351 void 352 sbfree_ktls_rx(struct sockbuf *sb, struct mbuf *m) 353 { 354 355 #if 0 /* XXX: not yet: soclose() call path comes here w/o lock. */ 356 SOCKBUF_LOCK_ASSERT(sb); 357 #endif 358 359 sb->sb_ccc -= m->m_len; 360 sb->sb_tlscc -= m->m_len; 361 362 sb->sb_mbcnt -= MSIZE; 363 364 if (m->m_flags & M_EXT) 365 sb->sb_mbcnt -= m->m_ext.ext_size; 366 } 367 #endif 368 369 /* 370 * Socantsendmore indicates that no more data will be sent on the socket; it 371 * would normally be applied to a socket when the user informs the system 372 * that no more data is to be sent, by the protocol code (in case 373 * PRU_SHUTDOWN). Socantrcvmore indicates that no more data will be 374 * received, and will normally be applied to the socket by a protocol when it 375 * detects that the peer will send no more data. Data queued for reading in 376 * the socket may yet be read. 377 */ 378 void 379 socantsendmore_locked(struct socket *so) 380 { 381 382 SOCK_SENDBUF_LOCK_ASSERT(so); 383 384 so->so_snd.sb_state |= SBS_CANTSENDMORE; 385 sowwakeup_locked(so); 386 SOCK_SENDBUF_UNLOCK_ASSERT(so); 387 } 388 389 void 390 socantsendmore(struct socket *so) 391 { 392 393 SOCK_SENDBUF_LOCK(so); 394 socantsendmore_locked(so); 395 SOCK_SENDBUF_UNLOCK_ASSERT(so); 396 } 397 398 void 399 socantrcvmore_locked(struct socket *so) 400 { 401 402 SOCK_RECVBUF_LOCK_ASSERT(so); 403 404 so->so_rcv.sb_state |= SBS_CANTRCVMORE; 405 #ifdef KERN_TLS 406 if (so->so_rcv.sb_flags & SB_TLS_RX) 407 ktls_check_rx(&so->so_rcv); 408 #endif 409 sorwakeup_locked(so); 410 SOCK_RECVBUF_UNLOCK_ASSERT(so); 411 } 412 413 void 414 socantrcvmore(struct socket *so) 415 { 416 417 SOCK_RECVBUF_LOCK(so); 418 socantrcvmore_locked(so); 419 SOCK_RECVBUF_UNLOCK_ASSERT(so); 420 } 421 422 void 423 soroverflow_locked(struct socket *so) 424 { 425 426 SOCK_RECVBUF_LOCK_ASSERT(so); 427 428 if (so->so_options & SO_RERROR) { 429 so->so_rerror = ENOBUFS; 430 sorwakeup_locked(so); 431 } else 432 SOCK_RECVBUF_UNLOCK(so); 433 434 SOCK_RECVBUF_UNLOCK_ASSERT(so); 435 } 436 437 void 438 soroverflow(struct socket *so) 439 { 440 441 SOCK_RECVBUF_LOCK(so); 442 soroverflow_locked(so); 443 SOCK_RECVBUF_UNLOCK_ASSERT(so); 444 } 445 446 /* 447 * Wait for data to arrive at/drain from a socket buffer. 448 */ 449 int 450 sbwait(struct socket *so, sb_which which) 451 { 452 struct sockbuf *sb; 453 454 SOCK_BUF_LOCK_ASSERT(so, which); 455 456 sb = sobuf(so, which); 457 sb->sb_flags |= SB_WAIT; 458 return (msleep_sbt(&sb->sb_acc, soeventmtx(so, which), 459 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait", 460 sb->sb_timeo, 0, 0)); 461 } 462 463 /* 464 * Wakeup processes waiting on a socket buffer. Do asynchronous notification 465 * via SIGIO if the socket has the SS_ASYNC flag set. 466 * 467 * Called with the socket buffer lock held; will release the lock by the end 468 * of the function. This allows the caller to acquire the socket buffer lock 469 * while testing for the need for various sorts of wakeup and hold it through 470 * to the point where it's no longer required. We currently hold the lock 471 * through calls out to other subsystems (with the exception of kqueue), and 472 * then release it to avoid lock order issues. It's not clear that's 473 * correct. 474 */ 475 static __always_inline void 476 sowakeup(struct socket *so, const sb_which which) 477 { 478 struct sockbuf *sb; 479 int ret; 480 481 SOCK_BUF_LOCK_ASSERT(so, which); 482 483 sb = sobuf(so, which); 484 selwakeuppri(sb->sb_sel, PSOCK); 485 if (!SEL_WAITING(sb->sb_sel)) 486 sb->sb_flags &= ~SB_SEL; 487 if (sb->sb_flags & SB_WAIT) { 488 sb->sb_flags &= ~SB_WAIT; 489 wakeup(&sb->sb_acc); 490 } 491 KNOTE_LOCKED(&sb->sb_sel->si_note, 0); 492 if (sb->sb_upcall != NULL) { 493 ret = sb->sb_upcall(so, sb->sb_upcallarg, M_NOWAIT); 494 if (ret == SU_ISCONNECTED) { 495 KASSERT(sb == &so->so_rcv, 496 ("SO_SND upcall returned SU_ISCONNECTED")); 497 soupcall_clear(so, SO_RCV); 498 } 499 } else 500 ret = SU_OK; 501 if (sb->sb_flags & SB_AIO) 502 sowakeup_aio(so, which); 503 SOCK_BUF_UNLOCK(so, which); 504 if (ret == SU_ISCONNECTED) 505 soisconnected(so); 506 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 507 pgsigio(&so->so_sigio, SIGIO, 0); 508 SOCK_BUF_UNLOCK_ASSERT(so, which); 509 } 510 511 static void 512 splice_push(struct socket *so) 513 { 514 struct so_splice *sp; 515 516 SOCK_RECVBUF_LOCK_ASSERT(so); 517 518 sp = so->so_splice; 519 mtx_lock(&sp->mtx); 520 SOCK_RECVBUF_UNLOCK(so); 521 so_splice_dispatch(sp); 522 } 523 524 static void 525 splice_pull(struct socket *so) 526 { 527 struct so_splice *sp; 528 529 SOCK_SENDBUF_LOCK_ASSERT(so); 530 531 sp = so->so_splice_back; 532 mtx_lock(&sp->mtx); 533 SOCK_SENDBUF_UNLOCK(so); 534 so_splice_dispatch(sp); 535 } 536 537 /* 538 * Do we need to notify the other side when I/O is possible? 539 */ 540 static __always_inline bool 541 sb_notify(const struct sockbuf *sb) 542 { 543 return ((sb->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | 544 SB_UPCALL | SB_AIO | SB_KNOTE)) != 0); 545 } 546 547 void 548 sorwakeup_locked(struct socket *so) 549 { 550 SOCK_RECVBUF_LOCK_ASSERT(so); 551 if (so->so_rcv.sb_flags & SB_SPLICED) 552 splice_push(so); 553 else if (sb_notify(&so->so_rcv)) 554 sowakeup(so, SO_RCV); 555 else 556 SOCK_RECVBUF_UNLOCK(so); 557 } 558 559 void 560 sowwakeup_locked(struct socket *so) 561 { 562 SOCK_SENDBUF_LOCK_ASSERT(so); 563 if (so->so_snd.sb_flags & SB_SPLICED) 564 splice_pull(so); 565 else if (sb_notify(&so->so_snd)) 566 sowakeup(so, SO_SND); 567 else 568 SOCK_SENDBUF_UNLOCK(so); 569 } 570 571 /* 572 * Socket buffer (struct sockbuf) utility routines. 573 * 574 * Each socket contains two socket buffers: one for sending data and one for 575 * receiving data. Each buffer contains a queue of mbufs, information about 576 * the number of mbufs and amount of data in the queue, and other fields 577 * allowing select() statements and notification on data availability to be 578 * implemented. 579 * 580 * Data stored in a socket buffer is maintained as a list of records. Each 581 * record is a list of mbufs chained together with the m_next field. Records 582 * are chained together with the m_nextpkt field. The upper level routine 583 * soreceive() expects the following conventions to be observed when placing 584 * information in the receive buffer: 585 * 586 * 1. If the protocol requires each message be preceded by the sender's name, 587 * then a record containing that name must be present before any 588 * associated data (mbuf's must be of type MT_SONAME). 589 * 2. If the protocol supports the exchange of ``access rights'' (really just 590 * additional data associated with the message), and there are ``rights'' 591 * to be received, then a record containing this data should be present 592 * (mbuf's must be of type MT_RIGHTS). 593 * 3. If a name or rights record exists, then it must be followed by a data 594 * record, perhaps of zero length. 595 * 596 * Before using a new socket structure it is first necessary to reserve 597 * buffer space to the socket, by calling sbreserve(). This should commit 598 * some of the available buffer space in the system buffer pool for the 599 * socket (currently, it does nothing but enforce limits). The space should 600 * be released by calling sbrelease() when the socket is destroyed. 601 */ 602 int 603 soreserve(struct socket *so, u_long sndcc, u_long rcvcc) 604 { 605 struct thread *td = curthread; 606 607 SOCK_SENDBUF_LOCK(so); 608 SOCK_RECVBUF_LOCK(so); 609 if (sbreserve_locked(so, SO_SND, sndcc, td) == 0) 610 goto bad; 611 if (sbreserve_locked(so, SO_RCV, rcvcc, td) == 0) 612 goto bad2; 613 if (so->so_rcv.sb_lowat == 0) 614 so->so_rcv.sb_lowat = 1; 615 if (so->so_snd.sb_lowat == 0) 616 so->so_snd.sb_lowat = MCLBYTES; 617 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 618 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 619 SOCK_RECVBUF_UNLOCK(so); 620 SOCK_SENDBUF_UNLOCK(so); 621 return (0); 622 bad2: 623 sbrelease_locked(so, SO_SND); 624 bad: 625 SOCK_RECVBUF_UNLOCK(so); 626 SOCK_SENDBUF_UNLOCK(so); 627 return (ENOBUFS); 628 } 629 630 static int 631 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 632 { 633 int error = 0; 634 u_long tmp_sb_max = sb_max; 635 636 error = sysctl_handle_long(oidp, &tmp_sb_max, arg2, req); 637 if (error || !req->newptr) 638 return (error); 639 if (tmp_sb_max < MSIZE + MCLBYTES) 640 return (EINVAL); 641 sb_max = tmp_sb_max; 642 sb_max_adj = BUF_MAX_ADJ(sb_max); 643 return (0); 644 } 645 646 /* 647 * Allot mbufs to a sockbuf. Attempt to scale mbmax so that mbcnt doesn't 648 * become limiting if buffering efficiency is near the normal case. 649 */ 650 bool 651 sbreserve_locked_limit(struct socket *so, sb_which which, u_long cc, 652 u_long buf_max, struct thread *td) 653 { 654 struct sockbuf *sb = sobuf(so, which); 655 rlim_t sbsize_limit; 656 657 SOCK_BUF_LOCK_ASSERT(so, which); 658 659 /* 660 * When a thread is passed, we take into account the thread's socket 661 * buffer size limit. The caller will generally pass curthread, but 662 * in the TCP input path, NULL will be passed to indicate that no 663 * appropriate thread resource limits are available. In that case, 664 * we don't apply a process limit. 665 */ 666 if (cc > BUF_MAX_ADJ(buf_max)) 667 return (false); 668 if (td != NULL) { 669 sbsize_limit = lim_cur(td, RLIMIT_SBSIZE); 670 } else 671 sbsize_limit = RLIM_INFINITY; 672 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 673 sbsize_limit)) 674 return (false); 675 sb->sb_mbmax = min(cc * sb_efficiency, buf_max); 676 if (sb->sb_lowat > sb->sb_hiwat) 677 sb->sb_lowat = sb->sb_hiwat; 678 return (true); 679 } 680 681 bool 682 sbreserve_locked(struct socket *so, sb_which which, u_long cc, 683 struct thread *td) 684 { 685 return (sbreserve_locked_limit(so, which, cc, sb_max, td)); 686 } 687 688 int 689 sbsetopt(struct socket *so, struct sockopt *sopt) 690 { 691 struct sockbuf *sb; 692 sb_which wh; 693 short *flags; 694 u_int cc, *hiwat, *lowat; 695 int error, optval; 696 697 error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); 698 if (error != 0) 699 return (error); 700 701 /* 702 * Values < 1 make no sense for any of these options, 703 * so disallow them. 704 */ 705 if (optval < 1) 706 return (EINVAL); 707 cc = optval; 708 709 sb = NULL; 710 SOCK_LOCK(so); 711 if (SOLISTENING(so)) { 712 switch (sopt->sopt_name) { 713 case SO_SNDLOWAT: 714 case SO_SNDBUF: 715 lowat = &so->sol_sbsnd_lowat; 716 hiwat = &so->sol_sbsnd_hiwat; 717 flags = &so->sol_sbsnd_flags; 718 break; 719 case SO_RCVLOWAT: 720 case SO_RCVBUF: 721 lowat = &so->sol_sbrcv_lowat; 722 hiwat = &so->sol_sbrcv_hiwat; 723 flags = &so->sol_sbrcv_flags; 724 break; 725 } 726 } else { 727 switch (sopt->sopt_name) { 728 case SO_SNDLOWAT: 729 case SO_SNDBUF: 730 sb = &so->so_snd; 731 wh = SO_SND; 732 break; 733 case SO_RCVLOWAT: 734 case SO_RCVBUF: 735 sb = &so->so_rcv; 736 wh = SO_RCV; 737 break; 738 } 739 flags = &sb->sb_flags; 740 hiwat = &sb->sb_hiwat; 741 lowat = &sb->sb_lowat; 742 SOCK_BUF_LOCK(so, wh); 743 } 744 745 error = 0; 746 switch (sopt->sopt_name) { 747 case SO_SNDBUF: 748 case SO_RCVBUF: 749 if (SOLISTENING(so)) { 750 if (cc > sb_max_adj) { 751 error = ENOBUFS; 752 break; 753 } 754 *hiwat = cc; 755 if (*lowat > *hiwat) 756 *lowat = *hiwat; 757 } else { 758 if (!sbreserve_locked(so, wh, cc, curthread)) 759 error = ENOBUFS; 760 } 761 if (error == 0) 762 *flags &= ~SB_AUTOSIZE; 763 break; 764 case SO_SNDLOWAT: 765 case SO_RCVLOWAT: 766 /* 767 * Make sure the low-water is never greater than the 768 * high-water. 769 */ 770 *lowat = (cc > *hiwat) ? *hiwat : cc; 771 break; 772 } 773 774 if (!SOLISTENING(so)) 775 SOCK_BUF_UNLOCK(so, wh); 776 SOCK_UNLOCK(so); 777 return (error); 778 } 779 780 /* 781 * Free mbufs held by a socket, and reserved mbuf space. 782 */ 783 static void 784 sbrelease_internal(struct socket *so, sb_which which) 785 { 786 struct sockbuf *sb = sobuf(so, which); 787 788 sbflush_internal(sb); 789 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0, 790 RLIM_INFINITY); 791 sb->sb_mbmax = 0; 792 } 793 794 void 795 sbrelease_locked(struct socket *so, sb_which which) 796 { 797 798 SOCK_BUF_LOCK_ASSERT(so, which); 799 800 sbrelease_internal(so, which); 801 } 802 803 void 804 sbrelease(struct socket *so, sb_which which) 805 { 806 807 SOCK_BUF_LOCK(so, which); 808 sbrelease_locked(so, which); 809 SOCK_BUF_UNLOCK(so, which); 810 } 811 812 void 813 sbdestroy(struct socket *so, sb_which which) 814 { 815 #ifdef KERN_TLS 816 struct sockbuf *sb = sobuf(so, which); 817 818 if (sb->sb_tls_info != NULL) 819 ktls_free(sb->sb_tls_info); 820 sb->sb_tls_info = NULL; 821 #endif 822 sbrelease_internal(so, which); 823 } 824 825 /* 826 * Routines to add and remove data from an mbuf queue. 827 * 828 * The routines sbappend() or sbappendrecord() are normally called to append 829 * new mbufs to a socket buffer, after checking that adequate space is 830 * available, comparing the function sbspace() with the amount of data to be 831 * added. sbappendrecord() differs from sbappend() in that data supplied is 832 * treated as the beginning of a new record. To place a sender's address, 833 * optional access rights, and data in a socket receive buffer, 834 * sbappendaddr() should be used. To place access rights and data in a 835 * socket receive buffer, sbappendrights() should be used. In either case, 836 * the new data begins a new record. Note that unlike sbappend() and 837 * sbappendrecord(), these routines check for the caller that there will be 838 * enough space to store the data. Each fails if there is not enough space, 839 * or if it cannot find mbufs to store additional information in. 840 * 841 * Reliable protocols may use the socket send buffer to hold data awaiting 842 * acknowledgement. Data is normally copied from a socket send buffer in a 843 * protocol with m_copy for output to a peer, and then removing the data from 844 * the socket buffer with sbdrop() or sbdroprecord() when the data is 845 * acknowledged by the peer. 846 */ 847 #ifdef SOCKBUF_DEBUG 848 void 849 sblastrecordchk(struct sockbuf *sb, const char *file, int line) 850 { 851 struct mbuf *m = sb->sb_mb; 852 853 SOCKBUF_LOCK_ASSERT(sb); 854 855 while (m && m->m_nextpkt) 856 m = m->m_nextpkt; 857 858 if (m != sb->sb_lastrecord) { 859 printf("%s: sb_mb %p sb_lastrecord %p last %p\n", 860 __func__, sb->sb_mb, sb->sb_lastrecord, m); 861 printf("packet chain:\n"); 862 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) 863 printf("\t%p\n", m); 864 panic("%s from %s:%u", __func__, file, line); 865 } 866 } 867 868 void 869 sblastmbufchk(struct sockbuf *sb, const char *file, int line) 870 { 871 struct mbuf *m = sb->sb_mb; 872 struct mbuf *n; 873 874 SOCKBUF_LOCK_ASSERT(sb); 875 876 while (m && m->m_nextpkt) 877 m = m->m_nextpkt; 878 879 while (m && m->m_next) 880 m = m->m_next; 881 882 if (m != sb->sb_mbtail) { 883 printf("%s: sb_mb %p sb_mbtail %p last %p\n", 884 __func__, sb->sb_mb, sb->sb_mbtail, m); 885 printf("packet tree:\n"); 886 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) { 887 printf("\t"); 888 for (n = m; n != NULL; n = n->m_next) 889 printf("%p ", n); 890 printf("\n"); 891 } 892 panic("%s from %s:%u", __func__, file, line); 893 } 894 895 #ifdef KERN_TLS 896 m = sb->sb_mtls; 897 while (m && m->m_next) 898 m = m->m_next; 899 900 if (m != sb->sb_mtlstail) { 901 printf("%s: sb_mtls %p sb_mtlstail %p last %p\n", 902 __func__, sb->sb_mtls, sb->sb_mtlstail, m); 903 printf("TLS packet tree:\n"); 904 printf("\t"); 905 for (m = sb->sb_mtls; m != NULL; m = m->m_next) { 906 printf("%p ", m); 907 } 908 printf("\n"); 909 panic("%s from %s:%u", __func__, file, line); 910 } 911 #endif 912 } 913 #endif /* SOCKBUF_DEBUG */ 914 915 #define SBLINKRECORD(sb, m0) do { \ 916 SOCKBUF_LOCK_ASSERT(sb); \ 917 if ((sb)->sb_lastrecord != NULL) \ 918 (sb)->sb_lastrecord->m_nextpkt = (m0); \ 919 else \ 920 (sb)->sb_mb = (m0); \ 921 (sb)->sb_lastrecord = (m0); \ 922 } while (/*CONSTCOND*/0) 923 924 /* 925 * Append mbuf chain m to the last record in the socket buffer sb. The 926 * additional space associated the mbuf chain is recorded in sb. Empty mbufs 927 * are discarded and mbufs are compacted where possible. 928 */ 929 void 930 sbappend_locked(struct sockbuf *sb, struct mbuf *m, int flags) 931 { 932 struct mbuf *n; 933 934 SOCKBUF_LOCK_ASSERT(sb); 935 936 if (m == NULL) 937 return; 938 kmsan_check_mbuf(m, "sbappend"); 939 sbm_clrprotoflags(m, flags); 940 SBLASTRECORDCHK(sb); 941 n = sb->sb_mb; 942 if (n) { 943 while (n->m_nextpkt) 944 n = n->m_nextpkt; 945 do { 946 if (n->m_flags & M_EOR) { 947 sbappendrecord_locked(sb, m); /* XXXXXX!!!! */ 948 return; 949 } 950 } while (n->m_next && (n = n->m_next)); 951 } else { 952 /* 953 * XXX Would like to simply use sb_mbtail here, but 954 * XXX I need to verify that I won't miss an EOR that 955 * XXX way. 956 */ 957 if ((n = sb->sb_lastrecord) != NULL) { 958 do { 959 if (n->m_flags & M_EOR) { 960 sbappendrecord_locked(sb, m); /* XXXXXX!!!! */ 961 return; 962 } 963 } while (n->m_next && (n = n->m_next)); 964 } else { 965 /* 966 * If this is the first record in the socket buffer, 967 * it's also the last record. 968 */ 969 sb->sb_lastrecord = m; 970 } 971 } 972 sbcompress(sb, m, n); 973 SBLASTRECORDCHK(sb); 974 } 975 976 /* 977 * Append mbuf chain m to the last record in the socket buffer sb. The 978 * additional space associated the mbuf chain is recorded in sb. Empty mbufs 979 * are discarded and mbufs are compacted where possible. 980 */ 981 void 982 sbappend(struct sockbuf *sb, struct mbuf *m, int flags) 983 { 984 985 SOCKBUF_LOCK(sb); 986 sbappend_locked(sb, m, flags); 987 SOCKBUF_UNLOCK(sb); 988 } 989 990 #ifdef KERN_TLS 991 /* 992 * Append an mbuf containing encrypted TLS data. The data 993 * is marked M_NOTREADY until it has been decrypted and 994 * stored as a TLS record. 995 */ 996 static void 997 sbappend_ktls_rx(struct sockbuf *sb, struct mbuf *m) 998 { 999 struct ifnet *ifp; 1000 struct mbuf *n; 1001 int flags; 1002 1003 ifp = NULL; 1004 flags = M_NOTREADY; 1005 1006 SBLASTMBUFCHK(sb); 1007 1008 /* Mbuf chain must start with a packet header. */ 1009 MPASS((m->m_flags & M_PKTHDR) != 0); 1010 1011 /* Remove all packet headers and mbuf tags to get a pure data chain. */ 1012 for (n = m; n != NULL; n = n->m_next) { 1013 if (n->m_flags & M_PKTHDR) { 1014 ifp = m->m_pkthdr.leaf_rcvif; 1015 if ((n->m_pkthdr.csum_flags & CSUM_TLS_MASK) == 1016 CSUM_TLS_DECRYPTED) { 1017 /* Mark all mbufs in this packet decrypted. */ 1018 flags = M_NOTREADY | M_DECRYPTED; 1019 } else { 1020 flags = M_NOTREADY; 1021 } 1022 m_demote_pkthdr(n); 1023 } 1024 1025 n->m_flags &= M_DEMOTEFLAGS; 1026 n->m_flags |= flags; 1027 1028 MPASS((n->m_flags & M_NOTREADY) != 0); 1029 } 1030 1031 sbcompress_ktls_rx(sb, m, sb->sb_mtlstail); 1032 ktls_check_rx(sb); 1033 1034 /* Check for incoming packet route changes: */ 1035 if (ifp != NULL && sb->sb_tls_info->rx_ifp != NULL && 1036 sb->sb_tls_info->rx_ifp != ifp) 1037 ktls_input_ifp_mismatch(sb, ifp); 1038 } 1039 #endif 1040 1041 /* 1042 * This version of sbappend() should only be used when the caller absolutely 1043 * knows that there will never be more than one record in the socket buffer, 1044 * that is, a stream protocol (such as TCP). 1045 */ 1046 void 1047 sbappendstream_locked(struct sockbuf *sb, struct mbuf *m, int flags) 1048 { 1049 SOCKBUF_LOCK_ASSERT(sb); 1050 1051 KASSERT(m->m_nextpkt == NULL,("sbappendstream 0")); 1052 1053 kmsan_check_mbuf(m, "sbappend"); 1054 1055 #ifdef KERN_TLS 1056 /* 1057 * Decrypted TLS records are appended as records via 1058 * sbappendrecord(). TCP passes encrypted TLS records to this 1059 * function which must be scheduled for decryption. 1060 */ 1061 if (sb->sb_flags & SB_TLS_RX) { 1062 sbappend_ktls_rx(sb, m); 1063 return; 1064 } 1065 #endif 1066 1067 KASSERT(sb->sb_mb == sb->sb_lastrecord,("sbappendstream 1")); 1068 1069 SBLASTMBUFCHK(sb); 1070 1071 #ifdef KERN_TLS 1072 if (sb->sb_tls_info != NULL) 1073 ktls_seq(sb, m); 1074 #endif 1075 1076 /* Remove all packet headers and mbuf tags to get a pure data chain. */ 1077 m_demote(m, 1, flags & PRUS_NOTREADY ? M_NOTREADY : 0); 1078 1079 sbcompress(sb, m, sb->sb_mbtail); 1080 1081 sb->sb_lastrecord = sb->sb_mb; 1082 SBLASTRECORDCHK(sb); 1083 } 1084 1085 /* 1086 * This version of sbappend() should only be used when the caller absolutely 1087 * knows that there will never be more than one record in the socket buffer, 1088 * that is, a stream protocol (such as TCP). 1089 */ 1090 void 1091 sbappendstream(struct sockbuf *sb, struct mbuf *m, int flags) 1092 { 1093 1094 SOCKBUF_LOCK(sb); 1095 sbappendstream_locked(sb, m, flags); 1096 SOCKBUF_UNLOCK(sb); 1097 } 1098 1099 #ifdef SOCKBUF_DEBUG 1100 void 1101 sbcheck(struct sockbuf *sb, const char *file, int line) 1102 { 1103 struct mbuf *m, *n, *fnrdy; 1104 u_long acc, ccc, mbcnt; 1105 #ifdef KERN_TLS 1106 u_long tlscc; 1107 #endif 1108 1109 SOCKBUF_LOCK_ASSERT(sb); 1110 1111 acc = ccc = mbcnt = 0; 1112 fnrdy = NULL; 1113 1114 for (m = sb->sb_mb; m; m = n) { 1115 n = m->m_nextpkt; 1116 for (; m; m = m->m_next) { 1117 if (m->m_len == 0) { 1118 printf("sb %p empty mbuf %p\n", sb, m); 1119 goto fail; 1120 } 1121 if ((m->m_flags & M_NOTREADY) && fnrdy == NULL) { 1122 if (m != sb->sb_fnrdy) { 1123 printf("sb %p: fnrdy %p != m %p\n", 1124 sb, sb->sb_fnrdy, m); 1125 goto fail; 1126 } 1127 fnrdy = m; 1128 } 1129 if (fnrdy) { 1130 if (!(m->m_flags & M_NOTAVAIL)) { 1131 printf("sb %p: fnrdy %p, m %p is avail\n", 1132 sb, sb->sb_fnrdy, m); 1133 goto fail; 1134 } 1135 } else 1136 acc += m->m_len; 1137 ccc += m->m_len; 1138 mbcnt += MSIZE; 1139 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 1140 mbcnt += m->m_ext.ext_size; 1141 } 1142 } 1143 #ifdef KERN_TLS 1144 /* 1145 * Account for mbufs "detached" by ktls_detach_record() while 1146 * they are decrypted by ktls_decrypt(). tlsdcc gives a count 1147 * of the detached bytes that are included in ccc. The mbufs 1148 * and clusters are not included in the socket buffer 1149 * accounting. 1150 */ 1151 ccc += sb->sb_tlsdcc; 1152 1153 tlscc = 0; 1154 for (m = sb->sb_mtls; m; m = m->m_next) { 1155 if (m->m_nextpkt != NULL) { 1156 printf("sb %p TLS mbuf %p with nextpkt\n", sb, m); 1157 goto fail; 1158 } 1159 if ((m->m_flags & M_NOTREADY) == 0) { 1160 printf("sb %p TLS mbuf %p ready\n", sb, m); 1161 goto fail; 1162 } 1163 tlscc += m->m_len; 1164 ccc += m->m_len; 1165 mbcnt += MSIZE; 1166 if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */ 1167 mbcnt += m->m_ext.ext_size; 1168 } 1169 1170 if (sb->sb_tlscc != tlscc) { 1171 printf("tlscc %ld/%u dcc %u\n", tlscc, sb->sb_tlscc, 1172 sb->sb_tlsdcc); 1173 goto fail; 1174 } 1175 #endif 1176 if (acc != sb->sb_acc || ccc != sb->sb_ccc || mbcnt != sb->sb_mbcnt) { 1177 printf("acc %ld/%u ccc %ld/%u mbcnt %ld/%u\n", 1178 acc, sb->sb_acc, ccc, sb->sb_ccc, mbcnt, sb->sb_mbcnt); 1179 #ifdef KERN_TLS 1180 printf("tlscc %ld/%u dcc %u\n", tlscc, sb->sb_tlscc, 1181 sb->sb_tlsdcc); 1182 #endif 1183 goto fail; 1184 } 1185 return; 1186 fail: 1187 panic("%s from %s:%u", __func__, file, line); 1188 } 1189 #endif 1190 1191 /* 1192 * As above, except the mbuf chain begins a new record. 1193 */ 1194 void 1195 sbappendrecord_locked(struct sockbuf *sb, struct mbuf *m0) 1196 { 1197 struct mbuf *m; 1198 1199 SOCKBUF_LOCK_ASSERT(sb); 1200 1201 if (m0 == NULL) 1202 return; 1203 1204 kmsan_check_mbuf(m0, "sbappend"); 1205 m_clrprotoflags(m0); 1206 1207 /* 1208 * Put the first mbuf on the queue. Note this permits zero length 1209 * records. 1210 */ 1211 sballoc(sb, m0); 1212 SBLASTRECORDCHK(sb); 1213 SBLINKRECORD(sb, m0); 1214 sb->sb_mbtail = m0; 1215 m = m0->m_next; 1216 m0->m_next = 0; 1217 if (m && (m0->m_flags & M_EOR)) { 1218 m0->m_flags &= ~M_EOR; 1219 m->m_flags |= M_EOR; 1220 } 1221 /* always call sbcompress() so it can do SBLASTMBUFCHK() */ 1222 sbcompress(sb, m, m0); 1223 } 1224 1225 /* 1226 * As above, except the mbuf chain begins a new record. 1227 */ 1228 void 1229 sbappendrecord(struct sockbuf *sb, struct mbuf *m0) 1230 { 1231 1232 SOCKBUF_LOCK(sb); 1233 sbappendrecord_locked(sb, m0); 1234 SOCKBUF_UNLOCK(sb); 1235 } 1236 1237 /* Helper routine that appends data, control, and address to a sockbuf. */ 1238 static int 1239 sbappendaddr_locked_internal(struct sockbuf *sb, const struct sockaddr *asa, 1240 struct mbuf *m0, struct mbuf *control, struct mbuf *ctrl_last) 1241 { 1242 struct mbuf *m, *n, *nlast; 1243 1244 if (m0 != NULL) 1245 kmsan_check_mbuf(m0, "sbappend"); 1246 if (control != NULL) 1247 kmsan_check_mbuf(control, "sbappend"); 1248 1249 #if MSIZE <= 256 1250 if (asa->sa_len > MLEN) 1251 return (0); 1252 #endif 1253 m = m_get(M_NOWAIT, MT_SONAME); 1254 if (m == NULL) 1255 return (0); 1256 m->m_len = asa->sa_len; 1257 bcopy(asa, mtod(m, caddr_t), asa->sa_len); 1258 if (m0) { 1259 M_ASSERT_NO_SND_TAG(m0); 1260 m_clrprotoflags(m0); 1261 m_tag_delete_chain(m0, NULL); 1262 /* 1263 * Clear some persistent info from pkthdr. 1264 * We don't use m_demote(), because some netgraph consumers 1265 * expect M_PKTHDR presence. 1266 */ 1267 m0->m_pkthdr.rcvif = NULL; 1268 m0->m_pkthdr.flowid = 0; 1269 m0->m_pkthdr.csum_flags = 0; 1270 m0->m_pkthdr.fibnum = 0; 1271 m0->m_pkthdr.rsstype = 0; 1272 } 1273 if (ctrl_last) 1274 ctrl_last->m_next = m0; /* concatenate data to control */ 1275 else 1276 control = m0; 1277 m->m_next = control; 1278 for (n = m; n->m_next != NULL; n = n->m_next) 1279 sballoc(sb, n); 1280 sballoc(sb, n); 1281 nlast = n; 1282 SBLINKRECORD(sb, m); 1283 1284 sb->sb_mbtail = nlast; 1285 SBLASTMBUFCHK(sb); 1286 1287 SBLASTRECORDCHK(sb); 1288 return (1); 1289 } 1290 1291 /* 1292 * Append address and data, and optionally, control (ancillary) data to the 1293 * receive queue of a socket. If present, m0 must include a packet header 1294 * with total length. Returns 0 if no space in sockbuf or insufficient 1295 * mbufs. 1296 */ 1297 int 1298 sbappendaddr_locked(struct sockbuf *sb, const struct sockaddr *asa, 1299 struct mbuf *m0, struct mbuf *control) 1300 { 1301 struct mbuf *ctrl_last; 1302 int space = asa->sa_len; 1303 1304 SOCKBUF_LOCK_ASSERT(sb); 1305 1306 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 1307 panic("sbappendaddr_locked"); 1308 if (m0) 1309 space += m0->m_pkthdr.len; 1310 space += m_length(control, &ctrl_last); 1311 1312 if (space > sbspace(sb)) 1313 return (0); 1314 return (sbappendaddr_locked_internal(sb, asa, m0, control, ctrl_last)); 1315 } 1316 1317 /* 1318 * Append address and data, and optionally, control (ancillary) data to the 1319 * receive queue of a socket. If present, m0 must include a packet header 1320 * with total length. Returns 0 if insufficient mbufs. Does not validate space 1321 * on the receiving sockbuf. 1322 */ 1323 int 1324 sbappendaddr_nospacecheck_locked(struct sockbuf *sb, const struct sockaddr *asa, 1325 struct mbuf *m0, struct mbuf *control) 1326 { 1327 struct mbuf *ctrl_last; 1328 1329 SOCKBUF_LOCK_ASSERT(sb); 1330 1331 ctrl_last = (control == NULL) ? NULL : m_last(control); 1332 return (sbappendaddr_locked_internal(sb, asa, m0, control, ctrl_last)); 1333 } 1334 1335 /* 1336 * Append address and data, and optionally, control (ancillary) data to the 1337 * receive queue of a socket. If present, m0 must include a packet header 1338 * with total length. Returns 0 if no space in sockbuf or insufficient 1339 * mbufs. 1340 */ 1341 int 1342 sbappendaddr(struct sockbuf *sb, const struct sockaddr *asa, 1343 struct mbuf *m0, struct mbuf *control) 1344 { 1345 int retval; 1346 1347 SOCKBUF_LOCK(sb); 1348 retval = sbappendaddr_locked(sb, asa, m0, control); 1349 SOCKBUF_UNLOCK(sb); 1350 return (retval); 1351 } 1352 1353 void 1354 sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0, 1355 struct mbuf *control, int flags) 1356 { 1357 struct mbuf *m, *mlast; 1358 1359 if (m0 != NULL) 1360 kmsan_check_mbuf(m0, "sbappend"); 1361 kmsan_check_mbuf(control, "sbappend"); 1362 1363 sbm_clrprotoflags(m0, flags); 1364 m_last(control)->m_next = m0; 1365 1366 SBLASTRECORDCHK(sb); 1367 1368 for (m = control; m->m_next; m = m->m_next) 1369 sballoc(sb, m); 1370 sballoc(sb, m); 1371 mlast = m; 1372 SBLINKRECORD(sb, control); 1373 1374 sb->sb_mbtail = mlast; 1375 SBLASTMBUFCHK(sb); 1376 1377 SBLASTRECORDCHK(sb); 1378 } 1379 1380 void 1381 sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control, 1382 int flags) 1383 { 1384 1385 SOCKBUF_LOCK(sb); 1386 sbappendcontrol_locked(sb, m0, control, flags); 1387 SOCKBUF_UNLOCK(sb); 1388 } 1389 1390 /* 1391 * Append the data in mbuf chain (m) into the socket buffer sb following mbuf 1392 * (n). If (n) is NULL, the buffer is presumed empty. 1393 * 1394 * When the data is compressed, mbufs in the chain may be handled in one of 1395 * three ways: 1396 * 1397 * (1) The mbuf may simply be dropped, if it contributes nothing (no data, no 1398 * record boundary, and no change in data type). 1399 * 1400 * (2) The mbuf may be coalesced -- i.e., data in the mbuf may be copied into 1401 * an mbuf already in the socket buffer. This can occur if an 1402 * appropriate mbuf exists, there is room, both mbufs are not marked as 1403 * not ready, and no merging of data types will occur. 1404 * 1405 * (3) The mbuf may be appended to the end of the existing mbuf chain. 1406 * 1407 * If any of the new mbufs is marked as M_EOR, mark the last mbuf appended as 1408 * end-of-record. 1409 */ 1410 void 1411 sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n) 1412 { 1413 int eor = 0; 1414 struct mbuf *o; 1415 1416 SOCKBUF_LOCK_ASSERT(sb); 1417 1418 while (m) { 1419 eor |= m->m_flags & M_EOR; 1420 if (m->m_len == 0 && 1421 (eor == 0 || 1422 (((o = m->m_next) || (o = n)) && 1423 o->m_type == m->m_type))) { 1424 if (sb->sb_lastrecord == m) 1425 sb->sb_lastrecord = m->m_next; 1426 m = m_free(m); 1427 continue; 1428 } 1429 if (n && (n->m_flags & M_EOR) == 0 && 1430 M_WRITABLE(n) && 1431 ((sb->sb_flags & SB_NOCOALESCE) == 0) && 1432 !(m->m_flags & M_NOTREADY) && 1433 !(n->m_flags & (M_NOTREADY | M_EXTPG)) && 1434 !mbuf_has_tls_session(m) && 1435 !mbuf_has_tls_session(n) && 1436 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 1437 m->m_len <= M_TRAILINGSPACE(n) && 1438 n->m_type == m->m_type) { 1439 m_copydata(m, 0, m->m_len, mtodo(n, n->m_len)); 1440 n->m_len += m->m_len; 1441 sb->sb_ccc += m->m_len; 1442 if (sb->sb_fnrdy == NULL) 1443 sb->sb_acc += m->m_len; 1444 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 1445 /* XXX: Probably don't need.*/ 1446 sb->sb_ctl += m->m_len; 1447 m = m_free(m); 1448 continue; 1449 } 1450 if (m->m_len <= MLEN && (m->m_flags & M_EXTPG) && 1451 (m->m_flags & M_NOTREADY) == 0 && 1452 !mbuf_has_tls_session(m)) 1453 (void)mb_unmapped_compress(m); 1454 if (n) 1455 n->m_next = m; 1456 else 1457 sb->sb_mb = m; 1458 sb->sb_mbtail = m; 1459 sballoc(sb, m); 1460 n = m; 1461 m->m_flags &= ~M_EOR; 1462 m = m->m_next; 1463 n->m_next = 0; 1464 } 1465 if (eor) { 1466 KASSERT(n != NULL, ("sbcompress: eor && n == NULL")); 1467 n->m_flags |= eor; 1468 } 1469 SBLASTMBUFCHK(sb); 1470 } 1471 1472 #ifdef KERN_TLS 1473 /* 1474 * A version of sbcompress() for encrypted TLS RX mbufs. These mbufs 1475 * are appended to the 'sb_mtls' chain instead of 'sb_mb' and are also 1476 * a bit simpler (no EOR markers, always MT_DATA, etc.). 1477 */ 1478 static void 1479 sbcompress_ktls_rx(struct sockbuf *sb, struct mbuf *m, struct mbuf *n) 1480 { 1481 1482 SOCKBUF_LOCK_ASSERT(sb); 1483 1484 while (m) { 1485 KASSERT((m->m_flags & M_EOR) == 0, 1486 ("TLS RX mbuf %p with EOR", m)); 1487 KASSERT(m->m_type == MT_DATA, 1488 ("TLS RX mbuf %p is not MT_DATA", m)); 1489 KASSERT((m->m_flags & M_NOTREADY) != 0, 1490 ("TLS RX mbuf %p ready", m)); 1491 KASSERT((m->m_flags & M_EXTPG) == 0, 1492 ("TLS RX mbuf %p unmapped", m)); 1493 1494 if (m->m_len == 0) { 1495 m = m_free(m); 1496 continue; 1497 } 1498 1499 /* 1500 * Even though both 'n' and 'm' are NOTREADY, it's ok 1501 * to coalesce the data. 1502 */ 1503 if (n && 1504 M_WRITABLE(n) && 1505 ((sb->sb_flags & SB_NOCOALESCE) == 0) && 1506 !((m->m_flags ^ n->m_flags) & M_DECRYPTED) && 1507 !(n->m_flags & M_EXTPG) && 1508 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 1509 m->m_len <= M_TRAILINGSPACE(n)) { 1510 m_copydata(m, 0, m->m_len, mtodo(n, n->m_len)); 1511 n->m_len += m->m_len; 1512 sb->sb_ccc += m->m_len; 1513 sb->sb_tlscc += m->m_len; 1514 m = m_free(m); 1515 continue; 1516 } 1517 if (n) 1518 n->m_next = m; 1519 else 1520 sb->sb_mtls = m; 1521 sb->sb_mtlstail = m; 1522 sballoc_ktls_rx(sb, m); 1523 n = m; 1524 m = m->m_next; 1525 n->m_next = NULL; 1526 } 1527 SBLASTMBUFCHK(sb); 1528 } 1529 #endif 1530 1531 /* 1532 * Free all mbufs in a sockbuf. Check that all resources are reclaimed. 1533 */ 1534 static void 1535 sbflush_internal(struct sockbuf *sb) 1536 { 1537 1538 while (sb->sb_mbcnt || sb->sb_tlsdcc) { 1539 /* 1540 * Don't call sbcut(sb, 0) if the leading mbuf is non-empty: 1541 * we would loop forever. Panic instead. 1542 */ 1543 if (sb->sb_ccc == 0 && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 1544 break; 1545 m_freem(sbcut_internal(sb, (int)sb->sb_ccc)); 1546 } 1547 KASSERT(sb->sb_ccc == 0 && sb->sb_mb == 0 && sb->sb_mbcnt == 0, 1548 ("%s: ccc %u mb %p mbcnt %u", __func__, 1549 sb->sb_ccc, (void *)sb->sb_mb, sb->sb_mbcnt)); 1550 } 1551 1552 void 1553 sbflush_locked(struct sockbuf *sb) 1554 { 1555 1556 SOCKBUF_LOCK_ASSERT(sb); 1557 sbflush_internal(sb); 1558 } 1559 1560 void 1561 sbflush(struct sockbuf *sb) 1562 { 1563 1564 SOCKBUF_LOCK(sb); 1565 sbflush_locked(sb); 1566 SOCKBUF_UNLOCK(sb); 1567 } 1568 1569 /* 1570 * Cut data from (the front of) a sockbuf. 1571 */ 1572 static struct mbuf * 1573 sbcut_internal(struct sockbuf *sb, int len) 1574 { 1575 struct mbuf *m, *next, *mfree; 1576 bool is_tls; 1577 1578 KASSERT(len >= 0, ("%s: len is %d but it is supposed to be >= 0", 1579 __func__, len)); 1580 KASSERT(len <= sb->sb_ccc, ("%s: len: %d is > ccc: %u", 1581 __func__, len, sb->sb_ccc)); 1582 1583 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 1584 is_tls = false; 1585 mfree = NULL; 1586 1587 while (len > 0) { 1588 if (m == NULL) { 1589 #ifdef KERN_TLS 1590 if (next == NULL && !is_tls) { 1591 if (sb->sb_tlsdcc != 0) { 1592 MPASS(len >= sb->sb_tlsdcc); 1593 len -= sb->sb_tlsdcc; 1594 sb->sb_ccc -= sb->sb_tlsdcc; 1595 sb->sb_tlsdcc = 0; 1596 if (len == 0) 1597 break; 1598 } 1599 next = sb->sb_mtls; 1600 is_tls = true; 1601 } 1602 #endif 1603 KASSERT(next, ("%s: no next, len %d", __func__, len)); 1604 m = next; 1605 next = m->m_nextpkt; 1606 } 1607 if (m->m_len > len) { 1608 KASSERT(!(m->m_flags & M_NOTAVAIL), 1609 ("%s: m %p M_NOTAVAIL", __func__, m)); 1610 m->m_len -= len; 1611 m->m_data += len; 1612 sb->sb_ccc -= len; 1613 sb->sb_acc -= len; 1614 if (sb->sb_sndptroff != 0) 1615 sb->sb_sndptroff -= len; 1616 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 1617 sb->sb_ctl -= len; 1618 break; 1619 } 1620 len -= m->m_len; 1621 #ifdef KERN_TLS 1622 if (is_tls) 1623 sbfree_ktls_rx(sb, m); 1624 else 1625 #endif 1626 sbfree(sb, m); 1627 /* 1628 * Do not put M_NOTREADY buffers to the free list, they 1629 * are referenced from outside. 1630 */ 1631 if (m->m_flags & M_NOTREADY && !is_tls) 1632 m = m->m_next; 1633 else { 1634 struct mbuf *n; 1635 1636 n = m->m_next; 1637 m->m_next = mfree; 1638 mfree = m; 1639 m = n; 1640 } 1641 } 1642 /* 1643 * Free any zero-length mbufs from the buffer. 1644 * For SOCK_DGRAM sockets such mbufs represent empty records. 1645 * XXX: For SOCK_STREAM sockets such mbufs can appear in the buffer, 1646 * when sosend_generic() needs to send only control data. 1647 */ 1648 while (m && m->m_len == 0) { 1649 struct mbuf *n; 1650 1651 sbfree(sb, m); 1652 n = m->m_next; 1653 m->m_next = mfree; 1654 mfree = m; 1655 m = n; 1656 } 1657 #ifdef KERN_TLS 1658 if (is_tls) { 1659 sb->sb_mb = NULL; 1660 sb->sb_mtls = m; 1661 if (m == NULL) 1662 sb->sb_mtlstail = NULL; 1663 } else 1664 #endif 1665 if (m) { 1666 sb->sb_mb = m; 1667 m->m_nextpkt = next; 1668 } else 1669 sb->sb_mb = next; 1670 /* 1671 * First part is an inline SB_EMPTY_FIXUP(). Second part makes sure 1672 * sb_lastrecord is up-to-date if we dropped part of the last record. 1673 */ 1674 m = sb->sb_mb; 1675 if (m == NULL) { 1676 sb->sb_mbtail = NULL; 1677 sb->sb_lastrecord = NULL; 1678 } else if (m->m_nextpkt == NULL) { 1679 sb->sb_lastrecord = m; 1680 } 1681 1682 return (mfree); 1683 } 1684 1685 /* 1686 * Drop data from (the front of) a sockbuf. 1687 */ 1688 void 1689 sbdrop_locked(struct sockbuf *sb, int len) 1690 { 1691 1692 SOCKBUF_LOCK_ASSERT(sb); 1693 m_freem(sbcut_internal(sb, len)); 1694 } 1695 1696 /* 1697 * Drop data from (the front of) a sockbuf, 1698 * and return it to caller. 1699 */ 1700 struct mbuf * 1701 sbcut_locked(struct sockbuf *sb, int len) 1702 { 1703 1704 SOCKBUF_LOCK_ASSERT(sb); 1705 return (sbcut_internal(sb, len)); 1706 } 1707 1708 void 1709 sbdrop(struct sockbuf *sb, int len) 1710 { 1711 struct mbuf *mfree; 1712 1713 SOCKBUF_LOCK(sb); 1714 mfree = sbcut_internal(sb, len); 1715 SOCKBUF_UNLOCK(sb); 1716 1717 m_freem(mfree); 1718 } 1719 1720 struct mbuf * 1721 sbsndptr_noadv(struct sockbuf *sb, uint32_t off, uint32_t *moff) 1722 { 1723 struct mbuf *m; 1724 1725 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__)); 1726 if (sb->sb_sndptr == NULL || sb->sb_sndptroff > off) { 1727 *moff = off; 1728 if (sb->sb_sndptr == NULL) { 1729 sb->sb_sndptr = sb->sb_mb; 1730 sb->sb_sndptroff = 0; 1731 } 1732 return (sb->sb_mb); 1733 } else { 1734 m = sb->sb_sndptr; 1735 off -= sb->sb_sndptroff; 1736 } 1737 *moff = off; 1738 return (m); 1739 } 1740 1741 void 1742 sbsndptr_adv(struct sockbuf *sb, struct mbuf *mb, uint32_t len) 1743 { 1744 /* 1745 * A small copy was done, advance forward the sb_sbsndptr to cover 1746 * it. 1747 */ 1748 struct mbuf *m; 1749 1750 if (mb != sb->sb_sndptr) { 1751 /* Did not copyout at the same mbuf */ 1752 return; 1753 } 1754 m = mb; 1755 while (m && (len > 0)) { 1756 if (len >= m->m_len) { 1757 len -= m->m_len; 1758 if (m->m_next) { 1759 sb->sb_sndptroff += m->m_len; 1760 sb->sb_sndptr = m->m_next; 1761 } 1762 m = m->m_next; 1763 } else { 1764 len = 0; 1765 } 1766 } 1767 } 1768 1769 /* 1770 * Return the first mbuf and the mbuf data offset for the provided 1771 * send offset without changing the "sb_sndptroff" field. 1772 */ 1773 struct mbuf * 1774 sbsndmbuf(struct sockbuf *sb, u_int off, u_int *moff) 1775 { 1776 struct mbuf *m; 1777 1778 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__)); 1779 1780 /* 1781 * If the "off" is below the stored offset, which happens on 1782 * retransmits, just use "sb_mb": 1783 */ 1784 if (sb->sb_sndptr == NULL || sb->sb_sndptroff > off) { 1785 m = sb->sb_mb; 1786 } else { 1787 m = sb->sb_sndptr; 1788 off -= sb->sb_sndptroff; 1789 } 1790 while (off > 0 && m != NULL) { 1791 if (off < m->m_len) 1792 break; 1793 off -= m->m_len; 1794 m = m->m_next; 1795 } 1796 *moff = off; 1797 return (m); 1798 } 1799 1800 /* 1801 * Drop a record off the front of a sockbuf and move the next record to the 1802 * front. 1803 */ 1804 void 1805 sbdroprecord_locked(struct sockbuf *sb) 1806 { 1807 struct mbuf *m; 1808 1809 SOCKBUF_LOCK_ASSERT(sb); 1810 1811 m = sb->sb_mb; 1812 if (m) { 1813 sb->sb_mb = m->m_nextpkt; 1814 do { 1815 sbfree(sb, m); 1816 m = m_free(m); 1817 } while (m); 1818 } 1819 SB_EMPTY_FIXUP(sb); 1820 } 1821 1822 /* 1823 * Drop a record off the front of a sockbuf and move the next record to the 1824 * front. 1825 */ 1826 void 1827 sbdroprecord(struct sockbuf *sb) 1828 { 1829 1830 SOCKBUF_LOCK(sb); 1831 sbdroprecord_locked(sb); 1832 SOCKBUF_UNLOCK(sb); 1833 } 1834 1835 /* 1836 * Create a "control" mbuf containing the specified data with the specified 1837 * type for presentation on a socket buffer. 1838 */ 1839 struct mbuf * 1840 sbcreatecontrol(const void *p, u_int size, int type, int level, int wait) 1841 { 1842 struct cmsghdr *cp; 1843 struct mbuf *m; 1844 1845 MBUF_CHECKSLEEP(wait); 1846 1847 if (wait == M_NOWAIT) { 1848 if (CMSG_SPACE(size) > MCLBYTES) 1849 return (NULL); 1850 } else 1851 KASSERT(CMSG_SPACE(size) <= MCLBYTES, 1852 ("%s: passed CMSG_SPACE(%u) > MCLBYTES", __func__, size)); 1853 1854 if (CMSG_SPACE(size) > MLEN) 1855 m = m_getcl(wait, MT_CONTROL, 0); 1856 else 1857 m = m_get(wait, MT_CONTROL); 1858 if (m == NULL) 1859 return (NULL); 1860 1861 KASSERT(CMSG_SPACE(size) <= M_TRAILINGSPACE(m), 1862 ("sbcreatecontrol: short mbuf")); 1863 /* 1864 * Don't leave the padding between the msg header and the 1865 * cmsg data and the padding after the cmsg data un-initialized. 1866 */ 1867 cp = mtod(m, struct cmsghdr *); 1868 bzero(cp, CMSG_SPACE(size)); 1869 if (p != NULL) 1870 (void)memcpy(CMSG_DATA(cp), p, size); 1871 m->m_len = CMSG_SPACE(size); 1872 cp->cmsg_len = CMSG_LEN(size); 1873 cp->cmsg_level = level; 1874 cp->cmsg_type = type; 1875 return (m); 1876 } 1877 1878 /* 1879 * This does the same for socket buffers that sotoxsocket does for sockets: 1880 * generate an user-format data structure describing the socket buffer. Note 1881 * that the xsockbuf structure, since it is always embedded in a socket, does 1882 * not include a self pointer nor a length. We make this entry point public 1883 * in case some other mechanism needs it. 1884 */ 1885 void 1886 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 1887 { 1888 1889 xsb->sb_cc = sb->sb_ccc; 1890 xsb->sb_hiwat = sb->sb_hiwat; 1891 xsb->sb_mbcnt = sb->sb_mbcnt; 1892 xsb->sb_mbmax = sb->sb_mbmax; 1893 xsb->sb_lowat = sb->sb_lowat; 1894 xsb->sb_flags = sb->sb_flags; 1895 xsb->sb_timeo = sb->sb_timeo; 1896 } 1897 1898 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 1899 static int dummy; 1900 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW | CTLFLAG_SKIP, &dummy, 0, ""); 1901 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, 1902 CTLTYPE_ULONG | CTLFLAG_RW | CTLFLAG_MPSAFE, &sb_max, 0, 1903 sysctl_handle_sb_max, "LU", 1904 "Maximum socket buffer size"); 1905 SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1906 &sb_efficiency, 0, "Socket buffer size waste factor"); 1907