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 /* 512 * Do we need to notify the other side when I/O is possible? 513 */ 514 static __always_inline bool 515 sb_notify(const struct sockbuf *sb) 516 { 517 return ((sb->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | 518 SB_UPCALL | SB_AIO | SB_KNOTE)) != 0); 519 } 520 521 void 522 sorwakeup_locked(struct socket *so) 523 { 524 SOCK_RECVBUF_LOCK_ASSERT(so); 525 if (sb_notify(&so->so_rcv)) 526 sowakeup(so, SO_RCV); 527 else 528 SOCK_RECVBUF_UNLOCK(so); 529 } 530 531 void 532 sowwakeup_locked(struct socket *so) 533 { 534 SOCK_SENDBUF_LOCK_ASSERT(so); 535 if (sb_notify(&so->so_snd)) 536 sowakeup(so, SO_SND); 537 else 538 SOCK_SENDBUF_UNLOCK(so); 539 } 540 541 /* 542 * Socket buffer (struct sockbuf) utility routines. 543 * 544 * Each socket contains two socket buffers: one for sending data and one for 545 * receiving data. Each buffer contains a queue of mbufs, information about 546 * the number of mbufs and amount of data in the queue, and other fields 547 * allowing select() statements and notification on data availability to be 548 * implemented. 549 * 550 * Data stored in a socket buffer is maintained as a list of records. Each 551 * record is a list of mbufs chained together with the m_next field. Records 552 * are chained together with the m_nextpkt field. The upper level routine 553 * soreceive() expects the following conventions to be observed when placing 554 * information in the receive buffer: 555 * 556 * 1. If the protocol requires each message be preceded by the sender's name, 557 * then a record containing that name must be present before any 558 * associated data (mbuf's must be of type MT_SONAME). 559 * 2. If the protocol supports the exchange of ``access rights'' (really just 560 * additional data associated with the message), and there are ``rights'' 561 * to be received, then a record containing this data should be present 562 * (mbuf's must be of type MT_RIGHTS). 563 * 3. If a name or rights record exists, then it must be followed by a data 564 * record, perhaps of zero length. 565 * 566 * Before using a new socket structure it is first necessary to reserve 567 * buffer space to the socket, by calling sbreserve(). This should commit 568 * some of the available buffer space in the system buffer pool for the 569 * socket (currently, it does nothing but enforce limits). The space should 570 * be released by calling sbrelease() when the socket is destroyed. 571 */ 572 int 573 soreserve(struct socket *so, u_long sndcc, u_long rcvcc) 574 { 575 struct thread *td = curthread; 576 577 SOCK_SENDBUF_LOCK(so); 578 SOCK_RECVBUF_LOCK(so); 579 if (sbreserve_locked(so, SO_SND, sndcc, td) == 0) 580 goto bad; 581 if (sbreserve_locked(so, SO_RCV, rcvcc, td) == 0) 582 goto bad2; 583 if (so->so_rcv.sb_lowat == 0) 584 so->so_rcv.sb_lowat = 1; 585 if (so->so_snd.sb_lowat == 0) 586 so->so_snd.sb_lowat = MCLBYTES; 587 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 588 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 589 SOCK_RECVBUF_UNLOCK(so); 590 SOCK_SENDBUF_UNLOCK(so); 591 return (0); 592 bad2: 593 sbrelease_locked(so, SO_SND); 594 bad: 595 SOCK_RECVBUF_UNLOCK(so); 596 SOCK_SENDBUF_UNLOCK(so); 597 return (ENOBUFS); 598 } 599 600 static int 601 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 602 { 603 int error = 0; 604 u_long tmp_sb_max = sb_max; 605 606 error = sysctl_handle_long(oidp, &tmp_sb_max, arg2, req); 607 if (error || !req->newptr) 608 return (error); 609 if (tmp_sb_max < MSIZE + MCLBYTES) 610 return (EINVAL); 611 sb_max = tmp_sb_max; 612 sb_max_adj = BUF_MAX_ADJ(sb_max); 613 return (0); 614 } 615 616 /* 617 * Allot mbufs to a sockbuf. Attempt to scale mbmax so that mbcnt doesn't 618 * become limiting if buffering efficiency is near the normal case. 619 */ 620 bool 621 sbreserve_locked_limit(struct socket *so, sb_which which, u_long cc, 622 u_long buf_max, struct thread *td) 623 { 624 struct sockbuf *sb = sobuf(so, which); 625 rlim_t sbsize_limit; 626 627 SOCK_BUF_LOCK_ASSERT(so, which); 628 629 /* 630 * When a thread is passed, we take into account the thread's socket 631 * buffer size limit. The caller will generally pass curthread, but 632 * in the TCP input path, NULL will be passed to indicate that no 633 * appropriate thread resource limits are available. In that case, 634 * we don't apply a process limit. 635 */ 636 if (cc > BUF_MAX_ADJ(buf_max)) 637 return (false); 638 if (td != NULL) { 639 sbsize_limit = lim_cur(td, RLIMIT_SBSIZE); 640 } else 641 sbsize_limit = RLIM_INFINITY; 642 if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc, 643 sbsize_limit)) 644 return (false); 645 sb->sb_mbmax = min(cc * sb_efficiency, buf_max); 646 if (sb->sb_lowat > sb->sb_hiwat) 647 sb->sb_lowat = sb->sb_hiwat; 648 return (true); 649 } 650 651 bool 652 sbreserve_locked(struct socket *so, sb_which which, u_long cc, 653 struct thread *td) 654 { 655 return (sbreserve_locked_limit(so, which, cc, sb_max, td)); 656 } 657 658 int 659 sbsetopt(struct socket *so, struct sockopt *sopt) 660 { 661 struct sockbuf *sb; 662 sb_which wh; 663 short *flags; 664 u_int cc, *hiwat, *lowat; 665 int error, optval; 666 667 error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); 668 if (error != 0) 669 return (error); 670 671 /* 672 * Values < 1 make no sense for any of these options, 673 * so disallow them. 674 */ 675 if (optval < 1) 676 return (EINVAL); 677 cc = optval; 678 679 sb = NULL; 680 SOCK_LOCK(so); 681 if (SOLISTENING(so)) { 682 switch (sopt->sopt_name) { 683 case SO_SNDLOWAT: 684 case SO_SNDBUF: 685 lowat = &so->sol_sbsnd_lowat; 686 hiwat = &so->sol_sbsnd_hiwat; 687 flags = &so->sol_sbsnd_flags; 688 break; 689 case SO_RCVLOWAT: 690 case SO_RCVBUF: 691 lowat = &so->sol_sbrcv_lowat; 692 hiwat = &so->sol_sbrcv_hiwat; 693 flags = &so->sol_sbrcv_flags; 694 break; 695 } 696 } else { 697 switch (sopt->sopt_name) { 698 case SO_SNDLOWAT: 699 case SO_SNDBUF: 700 sb = &so->so_snd; 701 wh = SO_SND; 702 break; 703 case SO_RCVLOWAT: 704 case SO_RCVBUF: 705 sb = &so->so_rcv; 706 wh = SO_RCV; 707 break; 708 } 709 flags = &sb->sb_flags; 710 hiwat = &sb->sb_hiwat; 711 lowat = &sb->sb_lowat; 712 SOCK_BUF_LOCK(so, wh); 713 } 714 715 error = 0; 716 switch (sopt->sopt_name) { 717 case SO_SNDBUF: 718 case SO_RCVBUF: 719 if (SOLISTENING(so)) { 720 if (cc > sb_max_adj) { 721 error = ENOBUFS; 722 break; 723 } 724 *hiwat = cc; 725 if (*lowat > *hiwat) 726 *lowat = *hiwat; 727 } else { 728 if (!sbreserve_locked(so, wh, cc, curthread)) 729 error = ENOBUFS; 730 } 731 if (error == 0) 732 *flags &= ~SB_AUTOSIZE; 733 break; 734 case SO_SNDLOWAT: 735 case SO_RCVLOWAT: 736 /* 737 * Make sure the low-water is never greater than the 738 * high-water. 739 */ 740 *lowat = (cc > *hiwat) ? *hiwat : cc; 741 break; 742 } 743 744 if (!SOLISTENING(so)) 745 SOCK_BUF_UNLOCK(so, wh); 746 SOCK_UNLOCK(so); 747 return (error); 748 } 749 750 /* 751 * Free mbufs held by a socket, and reserved mbuf space. 752 */ 753 static void 754 sbrelease_internal(struct socket *so, sb_which which) 755 { 756 struct sockbuf *sb = sobuf(so, which); 757 758 sbflush_internal(sb); 759 (void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0, 760 RLIM_INFINITY); 761 sb->sb_mbmax = 0; 762 } 763 764 void 765 sbrelease_locked(struct socket *so, sb_which which) 766 { 767 768 SOCK_BUF_LOCK_ASSERT(so, which); 769 770 sbrelease_internal(so, which); 771 } 772 773 void 774 sbrelease(struct socket *so, sb_which which) 775 { 776 777 SOCK_BUF_LOCK(so, which); 778 sbrelease_locked(so, which); 779 SOCK_BUF_UNLOCK(so, which); 780 } 781 782 void 783 sbdestroy(struct socket *so, sb_which which) 784 { 785 #ifdef KERN_TLS 786 struct sockbuf *sb = sobuf(so, which); 787 788 if (sb->sb_tls_info != NULL) 789 ktls_free(sb->sb_tls_info); 790 sb->sb_tls_info = NULL; 791 #endif 792 sbrelease_internal(so, which); 793 } 794 795 /* 796 * Routines to add and remove data from an mbuf queue. 797 * 798 * The routines sbappend() or sbappendrecord() are normally called to append 799 * new mbufs to a socket buffer, after checking that adequate space is 800 * available, comparing the function sbspace() with the amount of data to be 801 * added. sbappendrecord() differs from sbappend() in that data supplied is 802 * treated as the beginning of a new record. To place a sender's address, 803 * optional access rights, and data in a socket receive buffer, 804 * sbappendaddr() should be used. To place access rights and data in a 805 * socket receive buffer, sbappendrights() should be used. In either case, 806 * the new data begins a new record. Note that unlike sbappend() and 807 * sbappendrecord(), these routines check for the caller that there will be 808 * enough space to store the data. Each fails if there is not enough space, 809 * or if it cannot find mbufs to store additional information in. 810 * 811 * Reliable protocols may use the socket send buffer to hold data awaiting 812 * acknowledgement. Data is normally copied from a socket send buffer in a 813 * protocol with m_copy for output to a peer, and then removing the data from 814 * the socket buffer with sbdrop() or sbdroprecord() when the data is 815 * acknowledged by the peer. 816 */ 817 #ifdef SOCKBUF_DEBUG 818 void 819 sblastrecordchk(struct sockbuf *sb, const char *file, int line) 820 { 821 struct mbuf *m = sb->sb_mb; 822 823 SOCKBUF_LOCK_ASSERT(sb); 824 825 while (m && m->m_nextpkt) 826 m = m->m_nextpkt; 827 828 if (m != sb->sb_lastrecord) { 829 printf("%s: sb_mb %p sb_lastrecord %p last %p\n", 830 __func__, sb->sb_mb, sb->sb_lastrecord, m); 831 printf("packet chain:\n"); 832 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) 833 printf("\t%p\n", m); 834 panic("%s from %s:%u", __func__, file, line); 835 } 836 } 837 838 void 839 sblastmbufchk(struct sockbuf *sb, const char *file, int line) 840 { 841 struct mbuf *m = sb->sb_mb; 842 struct mbuf *n; 843 844 SOCKBUF_LOCK_ASSERT(sb); 845 846 while (m && m->m_nextpkt) 847 m = m->m_nextpkt; 848 849 while (m && m->m_next) 850 m = m->m_next; 851 852 if (m != sb->sb_mbtail) { 853 printf("%s: sb_mb %p sb_mbtail %p last %p\n", 854 __func__, sb->sb_mb, sb->sb_mbtail, m); 855 printf("packet tree:\n"); 856 for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) { 857 printf("\t"); 858 for (n = m; n != NULL; n = n->m_next) 859 printf("%p ", n); 860 printf("\n"); 861 } 862 panic("%s from %s:%u", __func__, file, line); 863 } 864 865 #ifdef KERN_TLS 866 m = sb->sb_mtls; 867 while (m && m->m_next) 868 m = m->m_next; 869 870 if (m != sb->sb_mtlstail) { 871 printf("%s: sb_mtls %p sb_mtlstail %p last %p\n", 872 __func__, sb->sb_mtls, sb->sb_mtlstail, m); 873 printf("TLS packet tree:\n"); 874 printf("\t"); 875 for (m = sb->sb_mtls; m != NULL; m = m->m_next) { 876 printf("%p ", m); 877 } 878 printf("\n"); 879 panic("%s from %s:%u", __func__, file, line); 880 } 881 #endif 882 } 883 #endif /* SOCKBUF_DEBUG */ 884 885 #define SBLINKRECORD(sb, m0) do { \ 886 SOCKBUF_LOCK_ASSERT(sb); \ 887 if ((sb)->sb_lastrecord != NULL) \ 888 (sb)->sb_lastrecord->m_nextpkt = (m0); \ 889 else \ 890 (sb)->sb_mb = (m0); \ 891 (sb)->sb_lastrecord = (m0); \ 892 } while (/*CONSTCOND*/0) 893 894 /* 895 * Append mbuf chain m to the last record in the socket buffer sb. The 896 * additional space associated the mbuf chain is recorded in sb. Empty mbufs 897 * are discarded and mbufs are compacted where possible. 898 */ 899 void 900 sbappend_locked(struct sockbuf *sb, struct mbuf *m, int flags) 901 { 902 struct mbuf *n; 903 904 SOCKBUF_LOCK_ASSERT(sb); 905 906 if (m == NULL) 907 return; 908 kmsan_check_mbuf(m, "sbappend"); 909 sbm_clrprotoflags(m, flags); 910 SBLASTRECORDCHK(sb); 911 n = sb->sb_mb; 912 if (n) { 913 while (n->m_nextpkt) 914 n = n->m_nextpkt; 915 do { 916 if (n->m_flags & M_EOR) { 917 sbappendrecord_locked(sb, m); /* XXXXXX!!!! */ 918 return; 919 } 920 } while (n->m_next && (n = n->m_next)); 921 } else { 922 /* 923 * XXX Would like to simply use sb_mbtail here, but 924 * XXX I need to verify that I won't miss an EOR that 925 * XXX way. 926 */ 927 if ((n = sb->sb_lastrecord) != NULL) { 928 do { 929 if (n->m_flags & M_EOR) { 930 sbappendrecord_locked(sb, m); /* XXXXXX!!!! */ 931 return; 932 } 933 } while (n->m_next && (n = n->m_next)); 934 } else { 935 /* 936 * If this is the first record in the socket buffer, 937 * it's also the last record. 938 */ 939 sb->sb_lastrecord = m; 940 } 941 } 942 sbcompress(sb, m, n); 943 SBLASTRECORDCHK(sb); 944 } 945 946 /* 947 * Append mbuf chain m to the last record in the socket buffer sb. The 948 * additional space associated the mbuf chain is recorded in sb. Empty mbufs 949 * are discarded and mbufs are compacted where possible. 950 */ 951 void 952 sbappend(struct sockbuf *sb, struct mbuf *m, int flags) 953 { 954 955 SOCKBUF_LOCK(sb); 956 sbappend_locked(sb, m, flags); 957 SOCKBUF_UNLOCK(sb); 958 } 959 960 #ifdef KERN_TLS 961 /* 962 * Append an mbuf containing encrypted TLS data. The data 963 * is marked M_NOTREADY until it has been decrypted and 964 * stored as a TLS record. 965 */ 966 static void 967 sbappend_ktls_rx(struct sockbuf *sb, struct mbuf *m) 968 { 969 struct ifnet *ifp; 970 struct mbuf *n; 971 int flags; 972 973 ifp = NULL; 974 flags = M_NOTREADY; 975 976 SBLASTMBUFCHK(sb); 977 978 /* Mbuf chain must start with a packet header. */ 979 MPASS((m->m_flags & M_PKTHDR) != 0); 980 981 /* Remove all packet headers and mbuf tags to get a pure data chain. */ 982 for (n = m; n != NULL; n = n->m_next) { 983 if (n->m_flags & M_PKTHDR) { 984 ifp = m->m_pkthdr.leaf_rcvif; 985 if ((n->m_pkthdr.csum_flags & CSUM_TLS_MASK) == 986 CSUM_TLS_DECRYPTED) { 987 /* Mark all mbufs in this packet decrypted. */ 988 flags = M_NOTREADY | M_DECRYPTED; 989 } else { 990 flags = M_NOTREADY; 991 } 992 m_demote_pkthdr(n); 993 } 994 995 n->m_flags &= M_DEMOTEFLAGS; 996 n->m_flags |= flags; 997 998 MPASS((n->m_flags & M_NOTREADY) != 0); 999 } 1000 1001 sbcompress_ktls_rx(sb, m, sb->sb_mtlstail); 1002 ktls_check_rx(sb); 1003 1004 /* Check for incoming packet route changes: */ 1005 if (ifp != NULL && sb->sb_tls_info->rx_ifp != NULL && 1006 sb->sb_tls_info->rx_ifp != ifp) 1007 ktls_input_ifp_mismatch(sb, ifp); 1008 } 1009 #endif 1010 1011 /* 1012 * This version of sbappend() should only be used when the caller absolutely 1013 * knows that there will never be more than one record in the socket buffer, 1014 * that is, a stream protocol (such as TCP). 1015 */ 1016 void 1017 sbappendstream_locked(struct sockbuf *sb, struct mbuf *m, int flags) 1018 { 1019 SOCKBUF_LOCK_ASSERT(sb); 1020 1021 KASSERT(m->m_nextpkt == NULL,("sbappendstream 0")); 1022 1023 kmsan_check_mbuf(m, "sbappend"); 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 1174 kmsan_check_mbuf(m0, "sbappend"); 1175 m_clrprotoflags(m0); 1176 1177 /* 1178 * Put the first mbuf on the queue. Note this permits zero length 1179 * records. 1180 */ 1181 sballoc(sb, m0); 1182 SBLASTRECORDCHK(sb); 1183 SBLINKRECORD(sb, m0); 1184 sb->sb_mbtail = m0; 1185 m = m0->m_next; 1186 m0->m_next = 0; 1187 if (m && (m0->m_flags & M_EOR)) { 1188 m0->m_flags &= ~M_EOR; 1189 m->m_flags |= M_EOR; 1190 } 1191 /* always call sbcompress() so it can do SBLASTMBUFCHK() */ 1192 sbcompress(sb, m, m0); 1193 } 1194 1195 /* 1196 * As above, except the mbuf chain begins a new record. 1197 */ 1198 void 1199 sbappendrecord(struct sockbuf *sb, struct mbuf *m0) 1200 { 1201 1202 SOCKBUF_LOCK(sb); 1203 sbappendrecord_locked(sb, m0); 1204 SOCKBUF_UNLOCK(sb); 1205 } 1206 1207 /* Helper routine that appends data, control, and address to a sockbuf. */ 1208 static int 1209 sbappendaddr_locked_internal(struct sockbuf *sb, const struct sockaddr *asa, 1210 struct mbuf *m0, struct mbuf *control, struct mbuf *ctrl_last) 1211 { 1212 struct mbuf *m, *n, *nlast; 1213 1214 if (m0 != NULL) 1215 kmsan_check_mbuf(m0, "sbappend"); 1216 if (control != NULL) 1217 kmsan_check_mbuf(control, "sbappend"); 1218 1219 #if MSIZE <= 256 1220 if (asa->sa_len > MLEN) 1221 return (0); 1222 #endif 1223 m = m_get(M_NOWAIT, MT_SONAME); 1224 if (m == NULL) 1225 return (0); 1226 m->m_len = asa->sa_len; 1227 bcopy(asa, mtod(m, caddr_t), asa->sa_len); 1228 if (m0) { 1229 M_ASSERT_NO_SND_TAG(m0); 1230 m_clrprotoflags(m0); 1231 m_tag_delete_chain(m0, NULL); 1232 /* 1233 * Clear some persistent info from pkthdr. 1234 * We don't use m_demote(), because some netgraph consumers 1235 * expect M_PKTHDR presence. 1236 */ 1237 m0->m_pkthdr.rcvif = NULL; 1238 m0->m_pkthdr.flowid = 0; 1239 m0->m_pkthdr.csum_flags = 0; 1240 m0->m_pkthdr.fibnum = 0; 1241 m0->m_pkthdr.rsstype = 0; 1242 } 1243 if (ctrl_last) 1244 ctrl_last->m_next = m0; /* concatenate data to control */ 1245 else 1246 control = m0; 1247 m->m_next = control; 1248 for (n = m; n->m_next != NULL; n = n->m_next) 1249 sballoc(sb, n); 1250 sballoc(sb, n); 1251 nlast = n; 1252 SBLINKRECORD(sb, m); 1253 1254 sb->sb_mbtail = nlast; 1255 SBLASTMBUFCHK(sb); 1256 1257 SBLASTRECORDCHK(sb); 1258 return (1); 1259 } 1260 1261 /* 1262 * Append address and data, and optionally, control (ancillary) data to the 1263 * receive queue of a socket. If present, m0 must include a packet header 1264 * with total length. Returns 0 if no space in sockbuf or insufficient 1265 * mbufs. 1266 */ 1267 int 1268 sbappendaddr_locked(struct sockbuf *sb, const struct sockaddr *asa, 1269 struct mbuf *m0, struct mbuf *control) 1270 { 1271 struct mbuf *ctrl_last; 1272 int space = asa->sa_len; 1273 1274 SOCKBUF_LOCK_ASSERT(sb); 1275 1276 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 1277 panic("sbappendaddr_locked"); 1278 if (m0) 1279 space += m0->m_pkthdr.len; 1280 space += m_length(control, &ctrl_last); 1281 1282 if (space > sbspace(sb)) 1283 return (0); 1284 return (sbappendaddr_locked_internal(sb, asa, m0, control, ctrl_last)); 1285 } 1286 1287 /* 1288 * Append address and data, and optionally, control (ancillary) data to the 1289 * receive queue of a socket. If present, m0 must include a packet header 1290 * with total length. Returns 0 if insufficient mbufs. Does not validate space 1291 * on the receiving sockbuf. 1292 */ 1293 int 1294 sbappendaddr_nospacecheck_locked(struct sockbuf *sb, const struct sockaddr *asa, 1295 struct mbuf *m0, struct mbuf *control) 1296 { 1297 struct mbuf *ctrl_last; 1298 1299 SOCKBUF_LOCK_ASSERT(sb); 1300 1301 ctrl_last = (control == NULL) ? NULL : m_last(control); 1302 return (sbappendaddr_locked_internal(sb, asa, m0, control, ctrl_last)); 1303 } 1304 1305 /* 1306 * Append address and data, and optionally, control (ancillary) data to the 1307 * receive queue of a socket. If present, m0 must include a packet header 1308 * with total length. Returns 0 if no space in sockbuf or insufficient 1309 * mbufs. 1310 */ 1311 int 1312 sbappendaddr(struct sockbuf *sb, const struct sockaddr *asa, 1313 struct mbuf *m0, struct mbuf *control) 1314 { 1315 int retval; 1316 1317 SOCKBUF_LOCK(sb); 1318 retval = sbappendaddr_locked(sb, asa, m0, control); 1319 SOCKBUF_UNLOCK(sb); 1320 return (retval); 1321 } 1322 1323 void 1324 sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0, 1325 struct mbuf *control, int flags) 1326 { 1327 struct mbuf *m, *mlast; 1328 1329 kmsan_check_mbuf(m0, "sbappend"); 1330 kmsan_check_mbuf(control, "sbappend"); 1331 1332 sbm_clrprotoflags(m0, flags); 1333 m_last(control)->m_next = m0; 1334 1335 SBLASTRECORDCHK(sb); 1336 1337 for (m = control; m->m_next; m = m->m_next) 1338 sballoc(sb, m); 1339 sballoc(sb, m); 1340 mlast = m; 1341 SBLINKRECORD(sb, control); 1342 1343 sb->sb_mbtail = mlast; 1344 SBLASTMBUFCHK(sb); 1345 1346 SBLASTRECORDCHK(sb); 1347 } 1348 1349 void 1350 sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control, 1351 int flags) 1352 { 1353 1354 SOCKBUF_LOCK(sb); 1355 sbappendcontrol_locked(sb, m0, control, flags); 1356 SOCKBUF_UNLOCK(sb); 1357 } 1358 1359 /* 1360 * Append the data in mbuf chain (m) into the socket buffer sb following mbuf 1361 * (n). If (n) is NULL, the buffer is presumed empty. 1362 * 1363 * When the data is compressed, mbufs in the chain may be handled in one of 1364 * three ways: 1365 * 1366 * (1) The mbuf may simply be dropped, if it contributes nothing (no data, no 1367 * record boundary, and no change in data type). 1368 * 1369 * (2) The mbuf may be coalesced -- i.e., data in the mbuf may be copied into 1370 * an mbuf already in the socket buffer. This can occur if an 1371 * appropriate mbuf exists, there is room, both mbufs are not marked as 1372 * not ready, and no merging of data types will occur. 1373 * 1374 * (3) The mbuf may be appended to the end of the existing mbuf chain. 1375 * 1376 * If any of the new mbufs is marked as M_EOR, mark the last mbuf appended as 1377 * end-of-record. 1378 */ 1379 void 1380 sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n) 1381 { 1382 int eor = 0; 1383 struct mbuf *o; 1384 1385 SOCKBUF_LOCK_ASSERT(sb); 1386 1387 while (m) { 1388 eor |= m->m_flags & M_EOR; 1389 if (m->m_len == 0 && 1390 (eor == 0 || 1391 (((o = m->m_next) || (o = n)) && 1392 o->m_type == m->m_type))) { 1393 if (sb->sb_lastrecord == m) 1394 sb->sb_lastrecord = m->m_next; 1395 m = m_free(m); 1396 continue; 1397 } 1398 if (n && (n->m_flags & M_EOR) == 0 && 1399 M_WRITABLE(n) && 1400 ((sb->sb_flags & SB_NOCOALESCE) == 0) && 1401 !(m->m_flags & M_NOTREADY) && 1402 !(n->m_flags & (M_NOTREADY | M_EXTPG)) && 1403 !mbuf_has_tls_session(m) && 1404 !mbuf_has_tls_session(n) && 1405 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 1406 m->m_len <= M_TRAILINGSPACE(n) && 1407 n->m_type == m->m_type) { 1408 m_copydata(m, 0, m->m_len, mtodo(n, n->m_len)); 1409 n->m_len += m->m_len; 1410 sb->sb_ccc += m->m_len; 1411 if (sb->sb_fnrdy == NULL) 1412 sb->sb_acc += m->m_len; 1413 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 1414 /* XXX: Probably don't need.*/ 1415 sb->sb_ctl += m->m_len; 1416 m = m_free(m); 1417 continue; 1418 } 1419 if (m->m_len <= MLEN && (m->m_flags & M_EXTPG) && 1420 (m->m_flags & M_NOTREADY) == 0 && 1421 !mbuf_has_tls_session(m)) 1422 (void)mb_unmapped_compress(m); 1423 if (n) 1424 n->m_next = m; 1425 else 1426 sb->sb_mb = m; 1427 sb->sb_mbtail = m; 1428 sballoc(sb, m); 1429 n = m; 1430 m->m_flags &= ~M_EOR; 1431 m = m->m_next; 1432 n->m_next = 0; 1433 } 1434 if (eor) { 1435 KASSERT(n != NULL, ("sbcompress: eor && n == NULL")); 1436 n->m_flags |= eor; 1437 } 1438 SBLASTMBUFCHK(sb); 1439 } 1440 1441 #ifdef KERN_TLS 1442 /* 1443 * A version of sbcompress() for encrypted TLS RX mbufs. These mbufs 1444 * are appended to the 'sb_mtls' chain instead of 'sb_mb' and are also 1445 * a bit simpler (no EOR markers, always MT_DATA, etc.). 1446 */ 1447 static void 1448 sbcompress_ktls_rx(struct sockbuf *sb, struct mbuf *m, struct mbuf *n) 1449 { 1450 1451 SOCKBUF_LOCK_ASSERT(sb); 1452 1453 while (m) { 1454 KASSERT((m->m_flags & M_EOR) == 0, 1455 ("TLS RX mbuf %p with EOR", m)); 1456 KASSERT(m->m_type == MT_DATA, 1457 ("TLS RX mbuf %p is not MT_DATA", m)); 1458 KASSERT((m->m_flags & M_NOTREADY) != 0, 1459 ("TLS RX mbuf %p ready", m)); 1460 KASSERT((m->m_flags & M_EXTPG) == 0, 1461 ("TLS RX mbuf %p unmapped", m)); 1462 1463 if (m->m_len == 0) { 1464 m = m_free(m); 1465 continue; 1466 } 1467 1468 /* 1469 * Even though both 'n' and 'm' are NOTREADY, it's ok 1470 * to coalesce the data. 1471 */ 1472 if (n && 1473 M_WRITABLE(n) && 1474 ((sb->sb_flags & SB_NOCOALESCE) == 0) && 1475 !((m->m_flags ^ n->m_flags) & M_DECRYPTED) && 1476 !(n->m_flags & M_EXTPG) && 1477 m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */ 1478 m->m_len <= M_TRAILINGSPACE(n)) { 1479 m_copydata(m, 0, m->m_len, mtodo(n, n->m_len)); 1480 n->m_len += m->m_len; 1481 sb->sb_ccc += m->m_len; 1482 sb->sb_tlscc += m->m_len; 1483 m = m_free(m); 1484 continue; 1485 } 1486 if (n) 1487 n->m_next = m; 1488 else 1489 sb->sb_mtls = m; 1490 sb->sb_mtlstail = m; 1491 sballoc_ktls_rx(sb, m); 1492 n = m; 1493 m = m->m_next; 1494 n->m_next = NULL; 1495 } 1496 SBLASTMBUFCHK(sb); 1497 } 1498 #endif 1499 1500 /* 1501 * Free all mbufs in a sockbuf. Check that all resources are reclaimed. 1502 */ 1503 static void 1504 sbflush_internal(struct sockbuf *sb) 1505 { 1506 1507 while (sb->sb_mbcnt || sb->sb_tlsdcc) { 1508 /* 1509 * Don't call sbcut(sb, 0) if the leading mbuf is non-empty: 1510 * we would loop forever. Panic instead. 1511 */ 1512 if (sb->sb_ccc == 0 && (sb->sb_mb == NULL || sb->sb_mb->m_len)) 1513 break; 1514 m_freem(sbcut_internal(sb, (int)sb->sb_ccc)); 1515 } 1516 KASSERT(sb->sb_ccc == 0 && sb->sb_mb == 0 && sb->sb_mbcnt == 0, 1517 ("%s: ccc %u mb %p mbcnt %u", __func__, 1518 sb->sb_ccc, (void *)sb->sb_mb, sb->sb_mbcnt)); 1519 } 1520 1521 void 1522 sbflush_locked(struct sockbuf *sb) 1523 { 1524 1525 SOCKBUF_LOCK_ASSERT(sb); 1526 sbflush_internal(sb); 1527 } 1528 1529 void 1530 sbflush(struct sockbuf *sb) 1531 { 1532 1533 SOCKBUF_LOCK(sb); 1534 sbflush_locked(sb); 1535 SOCKBUF_UNLOCK(sb); 1536 } 1537 1538 /* 1539 * Cut data from (the front of) a sockbuf. 1540 */ 1541 static struct mbuf * 1542 sbcut_internal(struct sockbuf *sb, int len) 1543 { 1544 struct mbuf *m, *next, *mfree; 1545 bool is_tls; 1546 1547 KASSERT(len >= 0, ("%s: len is %d but it is supposed to be >= 0", 1548 __func__, len)); 1549 KASSERT(len <= sb->sb_ccc, ("%s: len: %d is > ccc: %u", 1550 __func__, len, sb->sb_ccc)); 1551 1552 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 1553 is_tls = false; 1554 mfree = NULL; 1555 1556 while (len > 0) { 1557 if (m == NULL) { 1558 #ifdef KERN_TLS 1559 if (next == NULL && !is_tls) { 1560 if (sb->sb_tlsdcc != 0) { 1561 MPASS(len >= sb->sb_tlsdcc); 1562 len -= sb->sb_tlsdcc; 1563 sb->sb_ccc -= sb->sb_tlsdcc; 1564 sb->sb_tlsdcc = 0; 1565 if (len == 0) 1566 break; 1567 } 1568 next = sb->sb_mtls; 1569 is_tls = true; 1570 } 1571 #endif 1572 KASSERT(next, ("%s: no next, len %d", __func__, len)); 1573 m = next; 1574 next = m->m_nextpkt; 1575 } 1576 if (m->m_len > len) { 1577 KASSERT(!(m->m_flags & M_NOTAVAIL), 1578 ("%s: m %p M_NOTAVAIL", __func__, m)); 1579 m->m_len -= len; 1580 m->m_data += len; 1581 sb->sb_ccc -= len; 1582 sb->sb_acc -= len; 1583 if (sb->sb_sndptroff != 0) 1584 sb->sb_sndptroff -= len; 1585 if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA) 1586 sb->sb_ctl -= len; 1587 break; 1588 } 1589 len -= m->m_len; 1590 #ifdef KERN_TLS 1591 if (is_tls) 1592 sbfree_ktls_rx(sb, m); 1593 else 1594 #endif 1595 sbfree(sb, m); 1596 /* 1597 * Do not put M_NOTREADY buffers to the free list, they 1598 * are referenced from outside. 1599 */ 1600 if (m->m_flags & M_NOTREADY && !is_tls) 1601 m = m->m_next; 1602 else { 1603 struct mbuf *n; 1604 1605 n = m->m_next; 1606 m->m_next = mfree; 1607 mfree = m; 1608 m = n; 1609 } 1610 } 1611 /* 1612 * Free any zero-length mbufs from the buffer. 1613 * For SOCK_DGRAM sockets such mbufs represent empty records. 1614 * XXX: For SOCK_STREAM sockets such mbufs can appear in the buffer, 1615 * when sosend_generic() needs to send only control data. 1616 */ 1617 while (m && m->m_len == 0) { 1618 struct mbuf *n; 1619 1620 sbfree(sb, m); 1621 n = m->m_next; 1622 m->m_next = mfree; 1623 mfree = m; 1624 m = n; 1625 } 1626 #ifdef KERN_TLS 1627 if (is_tls) { 1628 sb->sb_mb = NULL; 1629 sb->sb_mtls = m; 1630 if (m == NULL) 1631 sb->sb_mtlstail = NULL; 1632 } else 1633 #endif 1634 if (m) { 1635 sb->sb_mb = m; 1636 m->m_nextpkt = next; 1637 } else 1638 sb->sb_mb = next; 1639 /* 1640 * First part is an inline SB_EMPTY_FIXUP(). Second part makes sure 1641 * sb_lastrecord is up-to-date if we dropped part of the last record. 1642 */ 1643 m = sb->sb_mb; 1644 if (m == NULL) { 1645 sb->sb_mbtail = NULL; 1646 sb->sb_lastrecord = NULL; 1647 } else if (m->m_nextpkt == NULL) { 1648 sb->sb_lastrecord = m; 1649 } 1650 1651 return (mfree); 1652 } 1653 1654 /* 1655 * Drop data from (the front of) a sockbuf. 1656 */ 1657 void 1658 sbdrop_locked(struct sockbuf *sb, int len) 1659 { 1660 1661 SOCKBUF_LOCK_ASSERT(sb); 1662 m_freem(sbcut_internal(sb, len)); 1663 } 1664 1665 /* 1666 * Drop data from (the front of) a sockbuf, 1667 * and return it to caller. 1668 */ 1669 struct mbuf * 1670 sbcut_locked(struct sockbuf *sb, int len) 1671 { 1672 1673 SOCKBUF_LOCK_ASSERT(sb); 1674 return (sbcut_internal(sb, len)); 1675 } 1676 1677 void 1678 sbdrop(struct sockbuf *sb, int len) 1679 { 1680 struct mbuf *mfree; 1681 1682 SOCKBUF_LOCK(sb); 1683 mfree = sbcut_internal(sb, len); 1684 SOCKBUF_UNLOCK(sb); 1685 1686 m_freem(mfree); 1687 } 1688 1689 struct mbuf * 1690 sbsndptr_noadv(struct sockbuf *sb, uint32_t off, uint32_t *moff) 1691 { 1692 struct mbuf *m; 1693 1694 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__)); 1695 if (sb->sb_sndptr == NULL || sb->sb_sndptroff > off) { 1696 *moff = off; 1697 if (sb->sb_sndptr == NULL) { 1698 sb->sb_sndptr = sb->sb_mb; 1699 sb->sb_sndptroff = 0; 1700 } 1701 return (sb->sb_mb); 1702 } else { 1703 m = sb->sb_sndptr; 1704 off -= sb->sb_sndptroff; 1705 } 1706 *moff = off; 1707 return (m); 1708 } 1709 1710 void 1711 sbsndptr_adv(struct sockbuf *sb, struct mbuf *mb, uint32_t len) 1712 { 1713 /* 1714 * A small copy was done, advance forward the sb_sbsndptr to cover 1715 * it. 1716 */ 1717 struct mbuf *m; 1718 1719 if (mb != sb->sb_sndptr) { 1720 /* Did not copyout at the same mbuf */ 1721 return; 1722 } 1723 m = mb; 1724 while (m && (len > 0)) { 1725 if (len >= m->m_len) { 1726 len -= m->m_len; 1727 if (m->m_next) { 1728 sb->sb_sndptroff += m->m_len; 1729 sb->sb_sndptr = m->m_next; 1730 } 1731 m = m->m_next; 1732 } else { 1733 len = 0; 1734 } 1735 } 1736 } 1737 1738 /* 1739 * Return the first mbuf and the mbuf data offset for the provided 1740 * send offset without changing the "sb_sndptroff" field. 1741 */ 1742 struct mbuf * 1743 sbsndmbuf(struct sockbuf *sb, u_int off, u_int *moff) 1744 { 1745 struct mbuf *m; 1746 1747 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__)); 1748 1749 /* 1750 * If the "off" is below the stored offset, which happens on 1751 * retransmits, just use "sb_mb": 1752 */ 1753 if (sb->sb_sndptr == NULL || sb->sb_sndptroff > off) { 1754 m = sb->sb_mb; 1755 } else { 1756 m = sb->sb_sndptr; 1757 off -= sb->sb_sndptroff; 1758 } 1759 while (off > 0 && m != NULL) { 1760 if (off < m->m_len) 1761 break; 1762 off -= m->m_len; 1763 m = m->m_next; 1764 } 1765 *moff = off; 1766 return (m); 1767 } 1768 1769 /* 1770 * Drop a record off the front of a sockbuf and move the next record to the 1771 * front. 1772 */ 1773 void 1774 sbdroprecord_locked(struct sockbuf *sb) 1775 { 1776 struct mbuf *m; 1777 1778 SOCKBUF_LOCK_ASSERT(sb); 1779 1780 m = sb->sb_mb; 1781 if (m) { 1782 sb->sb_mb = m->m_nextpkt; 1783 do { 1784 sbfree(sb, m); 1785 m = m_free(m); 1786 } while (m); 1787 } 1788 SB_EMPTY_FIXUP(sb); 1789 } 1790 1791 /* 1792 * Drop a record off the front of a sockbuf and move the next record to the 1793 * front. 1794 */ 1795 void 1796 sbdroprecord(struct sockbuf *sb) 1797 { 1798 1799 SOCKBUF_LOCK(sb); 1800 sbdroprecord_locked(sb); 1801 SOCKBUF_UNLOCK(sb); 1802 } 1803 1804 /* 1805 * Create a "control" mbuf containing the specified data with the specified 1806 * type for presentation on a socket buffer. 1807 */ 1808 struct mbuf * 1809 sbcreatecontrol(const void *p, u_int size, int type, int level, int wait) 1810 { 1811 struct cmsghdr *cp; 1812 struct mbuf *m; 1813 1814 MBUF_CHECKSLEEP(wait); 1815 1816 if (wait == M_NOWAIT) { 1817 if (CMSG_SPACE(size) > MCLBYTES) 1818 return (NULL); 1819 } else 1820 KASSERT(CMSG_SPACE(size) <= MCLBYTES, 1821 ("%s: passed CMSG_SPACE(%u) > MCLBYTES", __func__, size)); 1822 1823 if (CMSG_SPACE(size) > MLEN) 1824 m = m_getcl(wait, MT_CONTROL, 0); 1825 else 1826 m = m_get(wait, MT_CONTROL); 1827 if (m == NULL) 1828 return (NULL); 1829 1830 KASSERT(CMSG_SPACE(size) <= M_TRAILINGSPACE(m), 1831 ("sbcreatecontrol: short mbuf")); 1832 /* 1833 * Don't leave the padding between the msg header and the 1834 * cmsg data and the padding after the cmsg data un-initialized. 1835 */ 1836 cp = mtod(m, struct cmsghdr *); 1837 bzero(cp, CMSG_SPACE(size)); 1838 if (p != NULL) 1839 (void)memcpy(CMSG_DATA(cp), p, size); 1840 m->m_len = CMSG_SPACE(size); 1841 cp->cmsg_len = CMSG_LEN(size); 1842 cp->cmsg_level = level; 1843 cp->cmsg_type = type; 1844 return (m); 1845 } 1846 1847 /* 1848 * This does the same for socket buffers that sotoxsocket does for sockets: 1849 * generate an user-format data structure describing the socket buffer. Note 1850 * that the xsockbuf structure, since it is always embedded in a socket, does 1851 * not include a self pointer nor a length. We make this entry point public 1852 * in case some other mechanism needs it. 1853 */ 1854 void 1855 sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb) 1856 { 1857 1858 xsb->sb_cc = sb->sb_ccc; 1859 xsb->sb_hiwat = sb->sb_hiwat; 1860 xsb->sb_mbcnt = sb->sb_mbcnt; 1861 xsb->sb_mbmax = sb->sb_mbmax; 1862 xsb->sb_lowat = sb->sb_lowat; 1863 xsb->sb_flags = sb->sb_flags; 1864 xsb->sb_timeo = sb->sb_timeo; 1865 } 1866 1867 /* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */ 1868 static int dummy; 1869 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW | CTLFLAG_SKIP, &dummy, 0, ""); 1870 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, 1871 CTLTYPE_ULONG | CTLFLAG_RW | CTLFLAG_MPSAFE, &sb_max, 0, 1872 sysctl_handle_sb_max, "LU", 1873 "Maximum socket buffer size"); 1874 SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 1875 &sb_efficiency, 0, "Socket buffer size waste factor"); 1876