1 /* $OpenBSD: uipc_usrreq.c,v 1.199 2023/03/31 12:35:24 jsg Exp $ */ 2 /* $NetBSD: uipc_usrreq.c,v 1.18 1996/02/09 19:00:50 christos Exp $ */ 3 4 /* 5 * Copyright (c) 1982, 1986, 1989, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)uipc_usrreq.c 8.3 (Berkeley) 1/4/94 33 */ 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/proc.h> 38 #include <sys/filedesc.h> 39 #include <sys/domain.h> 40 #include <sys/protosw.h> 41 #include <sys/queue.h> 42 #include <sys/socket.h> 43 #include <sys/socketvar.h> 44 #include <sys/unpcb.h> 45 #include <sys/un.h> 46 #include <sys/namei.h> 47 #include <sys/vnode.h> 48 #include <sys/file.h> 49 #include <sys/stat.h> 50 #include <sys/mbuf.h> 51 #include <sys/task.h> 52 #include <sys/pledge.h> 53 #include <sys/pool.h> 54 #include <sys/rwlock.h> 55 #include <sys/mutex.h> 56 #include <sys/sysctl.h> 57 #include <sys/lock.h> 58 #include <sys/refcnt.h> 59 60 #include "kcov.h" 61 #if NKCOV > 0 62 #include <sys/kcov.h> 63 #endif 64 65 /* 66 * Locks used to protect global data and struct members: 67 * I immutable after creation 68 * D unp_df_lock 69 * G unp_gc_lock 70 * M unp_ino_mtx 71 * R unp_rights_mtx 72 * a atomic 73 * s socket lock 74 */ 75 76 struct rwlock unp_df_lock = RWLOCK_INITIALIZER("unpdflk"); 77 struct rwlock unp_gc_lock = RWLOCK_INITIALIZER("unpgclk"); 78 79 struct mutex unp_rights_mtx = MUTEX_INITIALIZER(IPL_SOFTNET); 80 struct mutex unp_ino_mtx = MUTEX_INITIALIZER(IPL_SOFTNET); 81 82 /* 83 * Stack of sets of files that were passed over a socket but were 84 * not received and need to be closed. 85 */ 86 struct unp_deferral { 87 SLIST_ENTRY(unp_deferral) ud_link; /* [D] */ 88 int ud_n; /* [I] */ 89 /* followed by ud_n struct fdpass */ 90 struct fdpass ud_fp[]; /* [I] */ 91 }; 92 93 void uipc_setaddr(const struct unpcb *, struct mbuf *); 94 void unp_discard(struct fdpass *, int); 95 void unp_remove_gcrefs(struct fdpass *, int); 96 void unp_restore_gcrefs(struct fdpass *, int); 97 void unp_scan(struct mbuf *, void (*)(struct fdpass *, int)); 98 int unp_nam2sun(struct mbuf *, struct sockaddr_un **, size_t *); 99 static inline void unp_ref(struct unpcb *); 100 static inline void unp_rele(struct unpcb *); 101 struct socket *unp_solock_peer(struct socket *); 102 103 struct pool unpcb_pool; 104 struct task unp_gc_task = TASK_INITIALIZER(unp_gc, NULL); 105 106 /* 107 * Unix communications domain. 108 * 109 * TODO: 110 * RDM 111 * rethink name space problems 112 * need a proper out-of-band 113 */ 114 const struct sockaddr sun_noname = { sizeof(sun_noname), AF_UNIX }; 115 116 /* [G] list of all UNIX domain sockets, for unp_gc() */ 117 LIST_HEAD(unp_head, unpcb) unp_head = 118 LIST_HEAD_INITIALIZER(unp_head); 119 /* [D] list of sets of files that were sent over sockets that are now closed */ 120 SLIST_HEAD(,unp_deferral) unp_deferred = 121 SLIST_HEAD_INITIALIZER(unp_deferred); 122 123 ino_t unp_ino; /* [U] prototype for fake inode numbers */ 124 int unp_rights; /* [R] file descriptors in flight */ 125 int unp_defer; /* [G] number of deferred fp to close by the GC task */ 126 int unp_gcing; /* [G] GC task currently running */ 127 128 const struct pr_usrreqs uipc_usrreqs = { 129 .pru_attach = uipc_attach, 130 .pru_detach = uipc_detach, 131 .pru_bind = uipc_bind, 132 .pru_listen = uipc_listen, 133 .pru_connect = uipc_connect, 134 .pru_accept = uipc_accept, 135 .pru_disconnect = uipc_disconnect, 136 .pru_shutdown = uipc_shutdown, 137 .pru_rcvd = uipc_rcvd, 138 .pru_send = uipc_send, 139 .pru_abort = uipc_abort, 140 .pru_sense = uipc_sense, 141 .pru_sockaddr = uipc_sockaddr, 142 .pru_peeraddr = uipc_peeraddr, 143 .pru_connect2 = uipc_connect2, 144 }; 145 146 const struct pr_usrreqs uipc_dgram_usrreqs = { 147 .pru_attach = uipc_attach, 148 .pru_detach = uipc_detach, 149 .pru_bind = uipc_bind, 150 .pru_listen = uipc_listen, 151 .pru_connect = uipc_connect, 152 .pru_disconnect = uipc_disconnect, 153 .pru_shutdown = uipc_dgram_shutdown, 154 .pru_send = uipc_dgram_send, 155 .pru_sense = uipc_sense, 156 .pru_sockaddr = uipc_sockaddr, 157 .pru_peeraddr = uipc_peeraddr, 158 .pru_connect2 = uipc_connect2, 159 }; 160 161 void 162 unp_init(void) 163 { 164 pool_init(&unpcb_pool, sizeof(struct unpcb), 0, 165 IPL_SOFTNET, 0, "unpcb", NULL); 166 } 167 168 static inline void 169 unp_ref(struct unpcb *unp) 170 { 171 refcnt_take(&unp->unp_refcnt); 172 } 173 174 static inline void 175 unp_rele(struct unpcb *unp) 176 { 177 refcnt_rele_wake(&unp->unp_refcnt); 178 } 179 180 struct socket * 181 unp_solock_peer(struct socket *so) 182 { 183 struct unpcb *unp, *unp2; 184 struct socket *so2; 185 186 unp = so->so_pcb; 187 188 again: 189 if ((unp2 = unp->unp_conn) == NULL) 190 return NULL; 191 192 so2 = unp2->unp_socket; 193 194 if (so < so2) 195 solock(so2); 196 else if (so > so2) { 197 unp_ref(unp2); 198 sounlock(so); 199 solock(so2); 200 solock(so); 201 202 /* Datagram socket could be reconnected due to re-lock. */ 203 if (unp->unp_conn != unp2) { 204 sounlock(so2); 205 unp_rele(unp2); 206 goto again; 207 } 208 209 unp_rele(unp2); 210 } 211 212 return so2; 213 } 214 215 void 216 uipc_setaddr(const struct unpcb *unp, struct mbuf *nam) 217 { 218 if (unp != NULL && unp->unp_addr != NULL) { 219 nam->m_len = unp->unp_addr->m_len; 220 memcpy(mtod(nam, caddr_t), mtod(unp->unp_addr, caddr_t), 221 nam->m_len); 222 } else { 223 nam->m_len = sizeof(sun_noname); 224 memcpy(mtod(nam, struct sockaddr *), &sun_noname, 225 nam->m_len); 226 } 227 } 228 229 /* 230 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 231 * for stream sockets, although the total for sender and receiver is 232 * actually only PIPSIZ. 233 * Datagram sockets really use the sendspace as the maximum datagram size, 234 * and don't really want to reserve the sendspace. Their recvspace should 235 * be large enough for at least one max-size datagram plus address. 236 */ 237 #define PIPSIZ 8192 238 u_int unpst_sendspace = PIPSIZ; 239 u_int unpst_recvspace = PIPSIZ; 240 u_int unpsq_sendspace = PIPSIZ; 241 u_int unpsq_recvspace = PIPSIZ; 242 u_int unpdg_sendspace = 2*1024; /* really max datagram size */ 243 u_int unpdg_recvspace = 16*1024; 244 245 const struct sysctl_bounded_args unpstctl_vars[] = { 246 { UNPCTL_RECVSPACE, &unpst_recvspace, 0, SB_MAX }, 247 { UNPCTL_SENDSPACE, &unpst_sendspace, 0, SB_MAX }, 248 }; 249 const struct sysctl_bounded_args unpsqctl_vars[] = { 250 { UNPCTL_RECVSPACE, &unpsq_recvspace, 0, SB_MAX }, 251 { UNPCTL_SENDSPACE, &unpsq_sendspace, 0, SB_MAX }, 252 }; 253 const struct sysctl_bounded_args unpdgctl_vars[] = { 254 { UNPCTL_RECVSPACE, &unpdg_recvspace, 0, SB_MAX }, 255 { UNPCTL_SENDSPACE, &unpdg_sendspace, 0, SB_MAX }, 256 }; 257 258 int 259 uipc_attach(struct socket *so, int proto, int wait) 260 { 261 struct unpcb *unp; 262 int error; 263 264 if (so->so_pcb) 265 return EISCONN; 266 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 267 switch (so->so_type) { 268 269 case SOCK_STREAM: 270 error = soreserve(so, unpst_sendspace, unpst_recvspace); 271 break; 272 273 case SOCK_SEQPACKET: 274 error = soreserve(so, unpsq_sendspace, unpsq_recvspace); 275 break; 276 277 case SOCK_DGRAM: 278 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 279 break; 280 281 default: 282 panic("unp_attach"); 283 } 284 if (error) 285 return (error); 286 } 287 unp = pool_get(&unpcb_pool, (wait == M_WAIT ? PR_WAITOK : PR_NOWAIT) | 288 PR_ZERO); 289 if (unp == NULL) 290 return (ENOBUFS); 291 refcnt_init(&unp->unp_refcnt); 292 unp->unp_socket = so; 293 so->so_pcb = unp; 294 getnanotime(&unp->unp_ctime); 295 296 /* 297 * Enforce `unp_gc_lock' -> `solock()' lock order. 298 */ 299 sounlock(so); 300 rw_enter_write(&unp_gc_lock); 301 LIST_INSERT_HEAD(&unp_head, unp, unp_link); 302 rw_exit_write(&unp_gc_lock); 303 solock(so); 304 return (0); 305 } 306 307 int 308 uipc_detach(struct socket *so) 309 { 310 struct unpcb *unp = sotounpcb(so); 311 312 if (unp == NULL) 313 return (EINVAL); 314 315 unp_detach(unp); 316 317 return (0); 318 } 319 320 int 321 uipc_bind(struct socket *so, struct mbuf *nam, struct proc *p) 322 { 323 struct unpcb *unp = sotounpcb(so); 324 struct sockaddr_un *soun; 325 struct mbuf *nam2; 326 struct vnode *vp; 327 struct vattr vattr; 328 int error; 329 struct nameidata nd; 330 size_t pathlen; 331 332 if (unp->unp_flags & (UNP_BINDING | UNP_CONNECTING)) 333 return (EINVAL); 334 if (unp->unp_vnode != NULL) 335 return (EINVAL); 336 if ((error = unp_nam2sun(nam, &soun, &pathlen))) 337 return (error); 338 339 unp->unp_flags |= UNP_BINDING; 340 341 /* 342 * Enforce `i_lock' -> `solock' because fifo subsystem 343 * requires it. The socket can't be closed concurrently 344 * because the file descriptor reference is still held. 345 */ 346 347 sounlock(unp->unp_socket); 348 349 nam2 = m_getclr(M_WAITOK, MT_SONAME); 350 nam2->m_len = sizeof(struct sockaddr_un); 351 memcpy(mtod(nam2, struct sockaddr_un *), soun, 352 offsetof(struct sockaddr_un, sun_path) + pathlen); 353 /* No need to NUL terminate: m_getclr() returns zero'd mbufs. */ 354 355 soun = mtod(nam2, struct sockaddr_un *); 356 357 /* Fixup sun_len to keep it in sync with m_len. */ 358 soun->sun_len = nam2->m_len; 359 360 NDINIT(&nd, CREATE, NOFOLLOW | LOCKPARENT, UIO_SYSSPACE, 361 soun->sun_path, p); 362 nd.ni_pledge = PLEDGE_UNIX; 363 nd.ni_unveil = UNVEIL_CREATE; 364 365 KERNEL_LOCK(); 366 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 367 error = namei(&nd); 368 if (error != 0) { 369 m_freem(nam2); 370 solock(unp->unp_socket); 371 goto out; 372 } 373 vp = nd.ni_vp; 374 if (vp != NULL) { 375 VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd); 376 if (nd.ni_dvp == vp) 377 vrele(nd.ni_dvp); 378 else 379 vput(nd.ni_dvp); 380 vrele(vp); 381 m_freem(nam2); 382 error = EADDRINUSE; 383 solock(unp->unp_socket); 384 goto out; 385 } 386 VATTR_NULL(&vattr); 387 vattr.va_type = VSOCK; 388 vattr.va_mode = ACCESSPERMS &~ p->p_fd->fd_cmask; 389 error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr); 390 vput(nd.ni_dvp); 391 if (error) { 392 m_freem(nam2); 393 solock(unp->unp_socket); 394 goto out; 395 } 396 solock(unp->unp_socket); 397 unp->unp_addr = nam2; 398 vp = nd.ni_vp; 399 vp->v_socket = unp->unp_socket; 400 unp->unp_vnode = vp; 401 unp->unp_connid.uid = p->p_ucred->cr_uid; 402 unp->unp_connid.gid = p->p_ucred->cr_gid; 403 unp->unp_connid.pid = p->p_p->ps_pid; 404 unp->unp_flags |= UNP_FEIDSBIND; 405 VOP_UNLOCK(vp); 406 out: 407 KERNEL_UNLOCK(); 408 unp->unp_flags &= ~UNP_BINDING; 409 410 return (error); 411 } 412 413 int 414 uipc_listen(struct socket *so) 415 { 416 struct unpcb *unp = sotounpcb(so); 417 418 if (unp->unp_vnode == NULL) 419 return (EINVAL); 420 return (0); 421 } 422 423 int 424 uipc_connect(struct socket *so, struct mbuf *nam) 425 { 426 return unp_connect(so, nam, curproc); 427 } 428 429 int 430 uipc_accept(struct socket *so, struct mbuf *nam) 431 { 432 struct socket *so2; 433 struct unpcb *unp = sotounpcb(so); 434 435 /* 436 * Pass back name of connected socket, if it was bound and 437 * we are still connected (our peer may have closed already!). 438 */ 439 so2 = unp_solock_peer(so); 440 uipc_setaddr(unp->unp_conn, nam); 441 442 if (so2 != NULL && so2 != so) 443 sounlock(so2); 444 return (0); 445 } 446 447 int 448 uipc_disconnect(struct socket *so) 449 { 450 struct unpcb *unp = sotounpcb(so); 451 452 unp_disconnect(unp); 453 return (0); 454 } 455 456 int 457 uipc_shutdown(struct socket *so) 458 { 459 struct unpcb *unp = sotounpcb(so); 460 struct socket *so2; 461 462 socantsendmore(so); 463 464 if ((so2 = unp_solock_peer(unp->unp_socket))){ 465 socantrcvmore(so2); 466 sounlock(so2); 467 } 468 469 return (0); 470 } 471 472 int 473 uipc_dgram_shutdown(struct socket *so) 474 { 475 socantsendmore(so); 476 return (0); 477 } 478 479 void 480 uipc_rcvd(struct socket *so) 481 { 482 struct socket *so2; 483 484 if ((so2 = unp_solock_peer(so)) == NULL) 485 return; 486 /* 487 * Adjust backpressure on sender 488 * and wakeup any waiting to write. 489 */ 490 so2->so_snd.sb_mbcnt = so->so_rcv.sb_mbcnt; 491 so2->so_snd.sb_cc = so->so_rcv.sb_cc; 492 sowwakeup(so2); 493 sounlock(so2); 494 } 495 496 int 497 uipc_send(struct socket *so, struct mbuf *m, struct mbuf *nam, 498 struct mbuf *control) 499 { 500 struct socket *so2; 501 int error = 0; 502 503 if (control) { 504 sounlock(so); 505 error = unp_internalize(control, curproc); 506 solock(so); 507 if (error) 508 goto out; 509 } 510 511 if (so->so_snd.sb_state & SS_CANTSENDMORE) { 512 error = EPIPE; 513 goto dispose; 514 } 515 if ((so2 = unp_solock_peer(so)) == NULL) { 516 error = ENOTCONN; 517 goto dispose; 518 } 519 520 /* 521 * Send to paired receive port, and then raise 522 * send buffer counts to maintain backpressure. 523 * Wake up readers. 524 */ 525 if (control) { 526 if (sbappendcontrol(so2, &so2->so_rcv, m, control)) { 527 control = NULL; 528 } else { 529 sounlock(so2); 530 error = ENOBUFS; 531 goto dispose; 532 } 533 } else if (so->so_type == SOCK_SEQPACKET) 534 sbappendrecord(so2, &so2->so_rcv, m); 535 else 536 sbappend(so2, &so2->so_rcv, m); 537 so->so_snd.sb_mbcnt = so2->so_rcv.sb_mbcnt; 538 so->so_snd.sb_cc = so2->so_rcv.sb_cc; 539 if (so2->so_rcv.sb_cc > 0) 540 sorwakeup(so2); 541 542 sounlock(so2); 543 m = NULL; 544 545 dispose: 546 /* we need to undo unp_internalize in case of errors */ 547 if (control && error) 548 unp_dispose(control); 549 550 out: 551 m_freem(control); 552 m_freem(m); 553 554 return (error); 555 } 556 557 int 558 uipc_dgram_send(struct socket *so, struct mbuf *m, struct mbuf *nam, 559 struct mbuf *control) 560 { 561 struct unpcb *unp = sotounpcb(so); 562 struct socket *so2; 563 const struct sockaddr *from; 564 int error = 0; 565 566 if (control) { 567 sounlock(so); 568 error = unp_internalize(control, curproc); 569 solock(so); 570 if (error) 571 goto out; 572 } 573 574 if (nam) { 575 if (unp->unp_conn) { 576 error = EISCONN; 577 goto dispose; 578 } 579 error = unp_connect(so, nam, curproc); 580 if (error) 581 goto dispose; 582 } 583 584 if ((so2 = unp_solock_peer(so)) == NULL) { 585 if (nam != NULL) 586 error = ECONNREFUSED; 587 else 588 error = ENOTCONN; 589 goto dispose; 590 } 591 592 if (unp->unp_addr) 593 from = mtod(unp->unp_addr, struct sockaddr *); 594 else 595 from = &sun_noname; 596 if (sbappendaddr(so2, &so2->so_rcv, from, m, control)) { 597 sorwakeup(so2); 598 m = NULL; 599 control = NULL; 600 } else 601 error = ENOBUFS; 602 603 if (so2 != so) 604 sounlock(so2); 605 606 if (nam) 607 unp_disconnect(unp); 608 609 dispose: 610 /* we need to undo unp_internalize in case of errors */ 611 if (control && error) 612 unp_dispose(control); 613 614 out: 615 m_freem(control); 616 m_freem(m); 617 618 return (error); 619 } 620 621 void 622 uipc_abort(struct socket *so) 623 { 624 struct unpcb *unp = sotounpcb(so); 625 626 unp_detach(unp); 627 sofree(so, 0); 628 } 629 630 int 631 uipc_sense(struct socket *so, struct stat *sb) 632 { 633 struct unpcb *unp = sotounpcb(so); 634 635 sb->st_blksize = so->so_snd.sb_hiwat; 636 sb->st_dev = NODEV; 637 mtx_enter(&unp_ino_mtx); 638 if (unp->unp_ino == 0) 639 unp->unp_ino = unp_ino++; 640 mtx_leave(&unp_ino_mtx); 641 sb->st_atim.tv_sec = 642 sb->st_mtim.tv_sec = 643 sb->st_ctim.tv_sec = unp->unp_ctime.tv_sec; 644 sb->st_atim.tv_nsec = 645 sb->st_mtim.tv_nsec = 646 sb->st_ctim.tv_nsec = unp->unp_ctime.tv_nsec; 647 sb->st_ino = unp->unp_ino; 648 649 return (0); 650 } 651 652 int 653 uipc_sockaddr(struct socket *so, struct mbuf *nam) 654 { 655 struct unpcb *unp = sotounpcb(so); 656 657 uipc_setaddr(unp, nam); 658 return (0); 659 } 660 661 int 662 uipc_peeraddr(struct socket *so, struct mbuf *nam) 663 { 664 struct unpcb *unp = sotounpcb(so); 665 struct socket *so2; 666 667 so2 = unp_solock_peer(so); 668 uipc_setaddr(unp->unp_conn, nam); 669 if (so2 != NULL && so2 != so) 670 sounlock(so2); 671 return (0); 672 } 673 674 int 675 uipc_connect2(struct socket *so, struct socket *so2) 676 { 677 struct unpcb *unp = sotounpcb(so), *unp2; 678 int error; 679 680 if ((error = unp_connect2(so, so2))) 681 return (error); 682 683 unp->unp_connid.uid = curproc->p_ucred->cr_uid; 684 unp->unp_connid.gid = curproc->p_ucred->cr_gid; 685 unp->unp_connid.pid = curproc->p_p->ps_pid; 686 unp->unp_flags |= UNP_FEIDS; 687 unp2 = sotounpcb(so2); 688 unp2->unp_connid.uid = curproc->p_ucred->cr_uid; 689 unp2->unp_connid.gid = curproc->p_ucred->cr_gid; 690 unp2->unp_connid.pid = curproc->p_p->ps_pid; 691 unp2->unp_flags |= UNP_FEIDS; 692 693 return (0); 694 } 695 696 int 697 uipc_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, 698 size_t newlen) 699 { 700 int *valp = &unp_defer; 701 702 /* All sysctl names at this level are terminal. */ 703 switch (name[0]) { 704 case SOCK_STREAM: 705 if (namelen != 2) 706 return (ENOTDIR); 707 return sysctl_bounded_arr(unpstctl_vars, nitems(unpstctl_vars), 708 name + 1, namelen - 1, oldp, oldlenp, newp, newlen); 709 case SOCK_SEQPACKET: 710 if (namelen != 2) 711 return (ENOTDIR); 712 return sysctl_bounded_arr(unpsqctl_vars, nitems(unpsqctl_vars), 713 name + 1, namelen - 1, oldp, oldlenp, newp, newlen); 714 case SOCK_DGRAM: 715 if (namelen != 2) 716 return (ENOTDIR); 717 return sysctl_bounded_arr(unpdgctl_vars, nitems(unpdgctl_vars), 718 name + 1, namelen - 1, oldp, oldlenp, newp, newlen); 719 case NET_UNIX_INFLIGHT: 720 valp = &unp_rights; 721 /* FALLTHOUGH */ 722 case NET_UNIX_DEFERRED: 723 if (namelen != 1) 724 return (ENOTDIR); 725 return sysctl_rdint(oldp, oldlenp, newp, *valp); 726 default: 727 return (ENOPROTOOPT); 728 } 729 } 730 731 void 732 unp_detach(struct unpcb *unp) 733 { 734 struct socket *so = unp->unp_socket; 735 struct vnode *vp = unp->unp_vnode; 736 struct unpcb *unp2; 737 738 unp->unp_vnode = NULL; 739 740 /* 741 * Enforce `unp_gc_lock' -> `solock()' lock order. 742 * Enforce `i_lock' -> `solock()' lock order. 743 */ 744 sounlock(so); 745 746 rw_enter_write(&unp_gc_lock); 747 LIST_REMOVE(unp, unp_link); 748 rw_exit_write(&unp_gc_lock); 749 750 if (vp != NULL) { 751 VOP_LOCK(vp, LK_EXCLUSIVE); 752 vp->v_socket = NULL; 753 754 KERNEL_LOCK(); 755 vput(vp); 756 KERNEL_UNLOCK(); 757 } 758 759 solock(so); 760 761 if (unp->unp_conn != NULL) { 762 /* 763 * Datagram socket could be connected to itself. 764 * Such socket will be disconnected here. 765 */ 766 unp_disconnect(unp); 767 } 768 769 while ((unp2 = SLIST_FIRST(&unp->unp_refs)) != NULL) { 770 struct socket *so2 = unp2->unp_socket; 771 772 if (so < so2) 773 solock(so2); 774 else { 775 unp_ref(unp2); 776 sounlock(so); 777 solock(so2); 778 solock(so); 779 780 if (unp2->unp_conn != unp) { 781 /* `unp2' was disconnected due to re-lock. */ 782 sounlock(so2); 783 unp_rele(unp2); 784 continue; 785 } 786 787 unp_rele(unp2); 788 } 789 790 unp2->unp_conn = NULL; 791 SLIST_REMOVE(&unp->unp_refs, unp2, unpcb, unp_nextref); 792 so2->so_error = ECONNRESET; 793 so2->so_state &= ~SS_ISCONNECTED; 794 795 sounlock(so2); 796 } 797 798 sounlock(so); 799 refcnt_finalize(&unp->unp_refcnt, "unpfinal"); 800 solock(so); 801 802 soisdisconnected(so); 803 so->so_pcb = NULL; 804 m_freem(unp->unp_addr); 805 pool_put(&unpcb_pool, unp); 806 if (unp_rights) 807 task_add(systqmp, &unp_gc_task); 808 } 809 810 int 811 unp_connect(struct socket *so, struct mbuf *nam, struct proc *p) 812 { 813 struct sockaddr_un *soun; 814 struct vnode *vp; 815 struct socket *so2, *so3; 816 struct unpcb *unp, *unp2, *unp3; 817 struct nameidata nd; 818 int error; 819 820 unp = sotounpcb(so); 821 if (unp->unp_flags & (UNP_BINDING | UNP_CONNECTING)) 822 return (EISCONN); 823 if ((error = unp_nam2sun(nam, &soun, NULL))) 824 return (error); 825 826 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, soun->sun_path, p); 827 nd.ni_pledge = PLEDGE_UNIX; 828 nd.ni_unveil = UNVEIL_WRITE; 829 830 unp->unp_flags |= UNP_CONNECTING; 831 832 /* 833 * Enforce `i_lock' -> `solock' because fifo subsystem 834 * requires it. The socket can't be closed concurrently 835 * because the file descriptor reference is still held. 836 */ 837 838 sounlock(so); 839 840 KERNEL_LOCK(); 841 error = namei(&nd); 842 if (error != 0) 843 goto unlock; 844 vp = nd.ni_vp; 845 if (vp->v_type != VSOCK) { 846 error = ENOTSOCK; 847 goto put; 848 } 849 if ((error = VOP_ACCESS(vp, VWRITE, p->p_ucred, p)) != 0) 850 goto put; 851 so2 = vp->v_socket; 852 if (so2 == NULL) { 853 error = ECONNREFUSED; 854 goto put; 855 } 856 if (so->so_type != so2->so_type) { 857 error = EPROTOTYPE; 858 goto put; 859 } 860 861 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 862 solock(so2); 863 864 if ((so2->so_options & SO_ACCEPTCONN) == 0 || 865 (so3 = sonewconn(so2, 0, M_WAIT)) == NULL) { 866 error = ECONNREFUSED; 867 } 868 869 sounlock(so2); 870 871 if (error != 0) 872 goto put; 873 874 /* 875 * Since `so2' is protected by vnode(9) lock, `so3' 876 * can't be PRU_ABORT'ed here. 877 */ 878 solock_pair(so, so3); 879 880 unp2 = sotounpcb(so2); 881 unp3 = sotounpcb(so3); 882 883 /* 884 * `unp_addr', `unp_connid' and 'UNP_FEIDSBIND' flag 885 * are immutable since we set them in uipc_bind(). 886 */ 887 if (unp2->unp_addr) 888 unp3->unp_addr = 889 m_copym(unp2->unp_addr, 0, M_COPYALL, M_NOWAIT); 890 unp3->unp_connid.uid = p->p_ucred->cr_uid; 891 unp3->unp_connid.gid = p->p_ucred->cr_gid; 892 unp3->unp_connid.pid = p->p_p->ps_pid; 893 unp3->unp_flags |= UNP_FEIDS; 894 895 if (unp2->unp_flags & UNP_FEIDSBIND) { 896 unp->unp_connid = unp2->unp_connid; 897 unp->unp_flags |= UNP_FEIDS; 898 } 899 900 so2 = so3; 901 } else { 902 if (so2 != so) 903 solock_pair(so, so2); 904 else 905 solock(so); 906 } 907 908 error = unp_connect2(so, so2); 909 910 sounlock(so); 911 912 /* 913 * `so2' can't be PRU_ABORT'ed concurrently 914 */ 915 if (so2 != so) 916 sounlock(so2); 917 put: 918 vput(vp); 919 unlock: 920 KERNEL_UNLOCK(); 921 solock(so); 922 unp->unp_flags &= ~UNP_CONNECTING; 923 924 /* 925 * The peer socket could be closed by concurrent thread 926 * when `so' and `vp' are unlocked. 927 */ 928 if (error == 0 && unp->unp_conn == NULL) 929 error = ECONNREFUSED; 930 931 return (error); 932 } 933 934 int 935 unp_connect2(struct socket *so, struct socket *so2) 936 { 937 struct unpcb *unp = sotounpcb(so); 938 struct unpcb *unp2; 939 940 soassertlocked(so); 941 soassertlocked(so2); 942 943 if (so2->so_type != so->so_type) 944 return (EPROTOTYPE); 945 unp2 = sotounpcb(so2); 946 unp->unp_conn = unp2; 947 switch (so->so_type) { 948 949 case SOCK_DGRAM: 950 SLIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_nextref); 951 soisconnected(so); 952 break; 953 954 case SOCK_STREAM: 955 case SOCK_SEQPACKET: 956 unp2->unp_conn = unp; 957 soisconnected(so); 958 soisconnected(so2); 959 break; 960 961 default: 962 panic("unp_connect2"); 963 } 964 return (0); 965 } 966 967 void 968 unp_disconnect(struct unpcb *unp) 969 { 970 struct socket *so2; 971 struct unpcb *unp2; 972 973 if ((so2 = unp_solock_peer(unp->unp_socket)) == NULL) 974 return; 975 976 unp2 = unp->unp_conn; 977 unp->unp_conn = NULL; 978 979 switch (unp->unp_socket->so_type) { 980 981 case SOCK_DGRAM: 982 SLIST_REMOVE(&unp2->unp_refs, unp, unpcb, unp_nextref); 983 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 984 break; 985 986 case SOCK_STREAM: 987 case SOCK_SEQPACKET: 988 unp->unp_socket->so_snd.sb_mbcnt = 0; 989 unp->unp_socket->so_snd.sb_cc = 0; 990 soisdisconnected(unp->unp_socket); 991 unp2->unp_conn = NULL; 992 unp2->unp_socket->so_snd.sb_mbcnt = 0; 993 unp2->unp_socket->so_snd.sb_cc = 0; 994 soisdisconnected(unp2->unp_socket); 995 break; 996 } 997 998 if (so2 != unp->unp_socket) 999 sounlock(so2); 1000 } 1001 1002 static struct unpcb * 1003 fptounp(struct file *fp) 1004 { 1005 struct socket *so; 1006 1007 if (fp->f_type != DTYPE_SOCKET) 1008 return (NULL); 1009 if ((so = fp->f_data) == NULL) 1010 return (NULL); 1011 if (so->so_proto->pr_domain != &unixdomain) 1012 return (NULL); 1013 return (sotounpcb(so)); 1014 } 1015 1016 int 1017 unp_externalize(struct mbuf *rights, socklen_t controllen, int flags) 1018 { 1019 struct proc *p = curproc; /* XXX */ 1020 struct cmsghdr *cm = mtod(rights, struct cmsghdr *); 1021 struct filedesc *fdp = p->p_fd; 1022 int i, *fds = NULL; 1023 struct fdpass *rp; 1024 struct file *fp; 1025 int nfds, error = 0; 1026 1027 /* 1028 * This code only works because SCM_RIGHTS is the only supported 1029 * control message type on unix sockets. Enforce this here. 1030 */ 1031 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET) 1032 return EINVAL; 1033 1034 nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) / 1035 sizeof(struct fdpass); 1036 if (controllen < CMSG_ALIGN(sizeof(struct cmsghdr))) 1037 controllen = 0; 1038 else 1039 controllen -= CMSG_ALIGN(sizeof(struct cmsghdr)); 1040 if (nfds > controllen / sizeof(int)) { 1041 error = EMSGSIZE; 1042 goto out; 1043 } 1044 1045 /* Make sure the recipient should be able to see the descriptors.. */ 1046 rp = (struct fdpass *)CMSG_DATA(cm); 1047 1048 /* fdp->fd_rdir requires KERNEL_LOCK() */ 1049 KERNEL_LOCK(); 1050 1051 for (i = 0; i < nfds; i++) { 1052 fp = rp->fp; 1053 rp++; 1054 error = pledge_recvfd(p, fp); 1055 if (error) 1056 break; 1057 1058 /* 1059 * No to block devices. If passing a directory, 1060 * make sure that it is underneath the root. 1061 */ 1062 if (fdp->fd_rdir != NULL && fp->f_type == DTYPE_VNODE) { 1063 struct vnode *vp = (struct vnode *)fp->f_data; 1064 1065 if (vp->v_type == VBLK || 1066 (vp->v_type == VDIR && 1067 !vn_isunder(vp, fdp->fd_rdir, p))) { 1068 error = EPERM; 1069 break; 1070 } 1071 } 1072 } 1073 1074 KERNEL_UNLOCK(); 1075 1076 if (error) 1077 goto out; 1078 1079 fds = mallocarray(nfds, sizeof(int), M_TEMP, M_WAITOK); 1080 1081 fdplock(fdp); 1082 restart: 1083 /* 1084 * First loop -- allocate file descriptor table slots for the 1085 * new descriptors. 1086 */ 1087 rp = ((struct fdpass *)CMSG_DATA(cm)); 1088 for (i = 0; i < nfds; i++) { 1089 if ((error = fdalloc(p, 0, &fds[i])) != 0) { 1090 /* 1091 * Back out what we've done so far. 1092 */ 1093 for (--i; i >= 0; i--) 1094 fdremove(fdp, fds[i]); 1095 1096 if (error == ENOSPC) { 1097 fdexpand(p); 1098 goto restart; 1099 } 1100 1101 fdpunlock(fdp); 1102 1103 /* 1104 * This is the error that has historically 1105 * been returned, and some callers may 1106 * expect it. 1107 */ 1108 1109 error = EMSGSIZE; 1110 goto out; 1111 } 1112 1113 /* 1114 * Make the slot reference the descriptor so that 1115 * fdalloc() works properly.. We finalize it all 1116 * in the loop below. 1117 */ 1118 mtx_enter(&fdp->fd_fplock); 1119 KASSERT(fdp->fd_ofiles[fds[i]] == NULL); 1120 fdp->fd_ofiles[fds[i]] = rp->fp; 1121 mtx_leave(&fdp->fd_fplock); 1122 1123 fdp->fd_ofileflags[fds[i]] = (rp->flags & UF_PLEDGED); 1124 if (flags & MSG_CMSG_CLOEXEC) 1125 fdp->fd_ofileflags[fds[i]] |= UF_EXCLOSE; 1126 1127 rp++; 1128 } 1129 1130 /* 1131 * Keep `fdp' locked to prevent concurrent close() of just 1132 * inserted descriptors. Such descriptors could have the only 1133 * `f_count' reference which is now shared between control 1134 * message and `fdp'. 1135 */ 1136 1137 /* 1138 * Now that adding them has succeeded, update all of the 1139 * descriptor passing state. 1140 */ 1141 rp = (struct fdpass *)CMSG_DATA(cm); 1142 1143 for (i = 0; i < nfds; i++) { 1144 struct unpcb *unp; 1145 1146 fp = rp->fp; 1147 rp++; 1148 if ((unp = fptounp(fp)) != NULL) { 1149 rw_enter_write(&unp_gc_lock); 1150 unp->unp_msgcount--; 1151 rw_exit_write(&unp_gc_lock); 1152 } 1153 } 1154 fdpunlock(fdp); 1155 1156 mtx_enter(&unp_rights_mtx); 1157 unp_rights -= nfds; 1158 mtx_leave(&unp_rights_mtx); 1159 1160 /* 1161 * Copy temporary array to message and adjust length, in case of 1162 * transition from large struct file pointers to ints. 1163 */ 1164 memcpy(CMSG_DATA(cm), fds, nfds * sizeof(int)); 1165 cm->cmsg_len = CMSG_LEN(nfds * sizeof(int)); 1166 rights->m_len = CMSG_LEN(nfds * sizeof(int)); 1167 out: 1168 if (fds != NULL) 1169 free(fds, M_TEMP, nfds * sizeof(int)); 1170 1171 if (error) { 1172 if (nfds > 0) { 1173 /* 1174 * No lock required. We are the only `cm' holder. 1175 */ 1176 rp = ((struct fdpass *)CMSG_DATA(cm)); 1177 unp_discard(rp, nfds); 1178 } 1179 } 1180 1181 return (error); 1182 } 1183 1184 int 1185 unp_internalize(struct mbuf *control, struct proc *p) 1186 { 1187 struct filedesc *fdp = p->p_fd; 1188 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1189 struct fdpass *rp; 1190 struct file *fp; 1191 struct unpcb *unp; 1192 int i, error; 1193 int nfds, *ip, fd, neededspace; 1194 1195 /* 1196 * Check for two potential msg_controllen values because 1197 * IETF stuck their nose in a place it does not belong. 1198 */ 1199 if (control->m_len < CMSG_LEN(0) || cm->cmsg_len < CMSG_LEN(0)) 1200 return (EINVAL); 1201 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET || 1202 !(cm->cmsg_len == control->m_len || 1203 control->m_len == CMSG_ALIGN(cm->cmsg_len))) 1204 return (EINVAL); 1205 nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) / sizeof (int); 1206 1207 mtx_enter(&unp_rights_mtx); 1208 if (unp_rights + nfds > maxfiles / 10) { 1209 mtx_leave(&unp_rights_mtx); 1210 return (EMFILE); 1211 } 1212 unp_rights += nfds; 1213 mtx_leave(&unp_rights_mtx); 1214 1215 /* Make sure we have room for the struct file pointers */ 1216 morespace: 1217 neededspace = CMSG_SPACE(nfds * sizeof(struct fdpass)) - 1218 control->m_len; 1219 if (neededspace > m_trailingspace(control)) { 1220 char *tmp; 1221 /* if we already have a cluster, the message is just too big */ 1222 if (control->m_flags & M_EXT) { 1223 error = E2BIG; 1224 goto nospace; 1225 } 1226 1227 /* copy cmsg data temporarily out of the mbuf */ 1228 tmp = malloc(control->m_len, M_TEMP, M_WAITOK); 1229 memcpy(tmp, mtod(control, caddr_t), control->m_len); 1230 1231 /* allocate a cluster and try again */ 1232 MCLGET(control, M_WAIT); 1233 if ((control->m_flags & M_EXT) == 0) { 1234 free(tmp, M_TEMP, control->m_len); 1235 error = ENOBUFS; /* allocation failed */ 1236 goto nospace; 1237 } 1238 1239 /* copy the data back into the cluster */ 1240 cm = mtod(control, struct cmsghdr *); 1241 memcpy(cm, tmp, control->m_len); 1242 free(tmp, M_TEMP, control->m_len); 1243 goto morespace; 1244 } 1245 1246 /* adjust message & mbuf to note amount of space actually used. */ 1247 cm->cmsg_len = CMSG_LEN(nfds * sizeof(struct fdpass)); 1248 control->m_len = CMSG_SPACE(nfds * sizeof(struct fdpass)); 1249 1250 ip = ((int *)CMSG_DATA(cm)) + nfds - 1; 1251 rp = ((struct fdpass *)CMSG_DATA(cm)) + nfds - 1; 1252 fdplock(fdp); 1253 for (i = 0; i < nfds; i++) { 1254 memcpy(&fd, ip, sizeof fd); 1255 ip--; 1256 if ((fp = fd_getfile(fdp, fd)) == NULL) { 1257 error = EBADF; 1258 goto fail; 1259 } 1260 if (fp->f_count >= FDUP_MAX_COUNT) { 1261 error = EDEADLK; 1262 goto fail; 1263 } 1264 error = pledge_sendfd(p, fp); 1265 if (error) 1266 goto fail; 1267 1268 /* kqueue descriptors cannot be copied */ 1269 if (fp->f_type == DTYPE_KQUEUE) { 1270 error = EINVAL; 1271 goto fail; 1272 } 1273 #if NKCOV > 0 1274 /* kcov descriptors cannot be copied */ 1275 if (fp->f_type == DTYPE_VNODE && kcov_vnode(fp->f_data)) { 1276 error = EINVAL; 1277 goto fail; 1278 } 1279 #endif 1280 rp->fp = fp; 1281 rp->flags = fdp->fd_ofileflags[fd] & UF_PLEDGED; 1282 rp--; 1283 if ((unp = fptounp(fp)) != NULL) { 1284 rw_enter_write(&unp_gc_lock); 1285 unp->unp_msgcount++; 1286 unp->unp_file = fp; 1287 rw_exit_write(&unp_gc_lock); 1288 } 1289 } 1290 fdpunlock(fdp); 1291 return (0); 1292 fail: 1293 fdpunlock(fdp); 1294 if (fp != NULL) 1295 FRELE(fp, p); 1296 /* Back out what we just did. */ 1297 for ( ; i > 0; i--) { 1298 rp++; 1299 fp = rp->fp; 1300 if ((unp = fptounp(fp)) != NULL) { 1301 rw_enter_write(&unp_gc_lock); 1302 unp->unp_msgcount--; 1303 rw_exit_write(&unp_gc_lock); 1304 } 1305 FRELE(fp, p); 1306 } 1307 1308 nospace: 1309 mtx_enter(&unp_rights_mtx); 1310 unp_rights -= nfds; 1311 mtx_leave(&unp_rights_mtx); 1312 1313 return (error); 1314 } 1315 1316 void 1317 unp_gc(void *arg __unused) 1318 { 1319 struct unp_deferral *defer; 1320 struct file *fp; 1321 struct socket *so; 1322 struct unpcb *unp; 1323 int nunref, i; 1324 1325 rw_enter_write(&unp_gc_lock); 1326 if (unp_gcing) 1327 goto unlock; 1328 unp_gcing = 1; 1329 rw_exit_write(&unp_gc_lock); 1330 1331 rw_enter_write(&unp_df_lock); 1332 /* close any fds on the deferred list */ 1333 while ((defer = SLIST_FIRST(&unp_deferred)) != NULL) { 1334 SLIST_REMOVE_HEAD(&unp_deferred, ud_link); 1335 rw_exit_write(&unp_df_lock); 1336 for (i = 0; i < defer->ud_n; i++) { 1337 fp = defer->ud_fp[i].fp; 1338 if (fp == NULL) 1339 continue; 1340 if ((unp = fptounp(fp)) != NULL) { 1341 rw_enter_write(&unp_gc_lock); 1342 unp->unp_msgcount--; 1343 rw_exit_write(&unp_gc_lock); 1344 } 1345 mtx_enter(&unp_rights_mtx); 1346 unp_rights--; 1347 mtx_leave(&unp_rights_mtx); 1348 /* closef() expects a refcount of 2 */ 1349 FREF(fp); 1350 (void) closef(fp, NULL); 1351 } 1352 free(defer, M_TEMP, sizeof(*defer) + 1353 sizeof(struct fdpass) * defer->ud_n); 1354 rw_enter_write(&unp_df_lock); 1355 } 1356 rw_exit_write(&unp_df_lock); 1357 1358 nunref = 0; 1359 1360 rw_enter_write(&unp_gc_lock); 1361 1362 /* 1363 * Determine sockets which may be prospectively dead. Such 1364 * sockets have their `unp_msgcount' equal to the `f_count'. 1365 * If `unp_msgcount' is 0, the socket has not been passed 1366 * and can't be unreferenced. 1367 */ 1368 LIST_FOREACH(unp, &unp_head, unp_link) { 1369 unp->unp_gcflags = 0; 1370 1371 if (unp->unp_msgcount == 0) 1372 continue; 1373 if ((fp = unp->unp_file) == NULL) 1374 continue; 1375 if (fp->f_count == unp->unp_msgcount) { 1376 unp->unp_gcflags |= UNP_GCDEAD; 1377 unp->unp_gcrefs = unp->unp_msgcount; 1378 nunref++; 1379 } 1380 } 1381 1382 /* 1383 * Scan all sockets previously marked as dead. Remove 1384 * the `unp_gcrefs' reference each socket holds on any 1385 * dead socket in its buffer. 1386 */ 1387 LIST_FOREACH(unp, &unp_head, unp_link) { 1388 if ((unp->unp_gcflags & UNP_GCDEAD) == 0) 1389 continue; 1390 so = unp->unp_socket; 1391 solock(so); 1392 unp_scan(so->so_rcv.sb_mb, unp_remove_gcrefs); 1393 sounlock(so); 1394 } 1395 1396 /* 1397 * If the dead socket has `unp_gcrefs' reference counter 1398 * greater than 0, it can't be unreferenced. Mark it as 1399 * alive and increment the `unp_gcrefs' reference for each 1400 * dead socket within its buffer. Repeat this until we 1401 * have no new alive sockets found. 1402 */ 1403 do { 1404 unp_defer = 0; 1405 1406 LIST_FOREACH(unp, &unp_head, unp_link) { 1407 if ((unp->unp_gcflags & UNP_GCDEAD) == 0) 1408 continue; 1409 if (unp->unp_gcrefs == 0) 1410 continue; 1411 1412 unp->unp_gcflags &= ~UNP_GCDEAD; 1413 1414 so = unp->unp_socket; 1415 solock(so); 1416 unp_scan(so->so_rcv.sb_mb, unp_restore_gcrefs); 1417 sounlock(so); 1418 1419 KASSERT(nunref > 0); 1420 nunref--; 1421 } 1422 } while (unp_defer > 0); 1423 1424 /* 1425 * If there are any unreferenced sockets, then for each dispose 1426 * of files in its receive buffer and then close it. 1427 */ 1428 if (nunref) { 1429 LIST_FOREACH(unp, &unp_head, unp_link) { 1430 if (unp->unp_gcflags & UNP_GCDEAD) { 1431 /* 1432 * This socket could still be connected 1433 * and if so it's `so_rcv' is still 1434 * accessible by concurrent PRU_SEND 1435 * thread. 1436 */ 1437 so = unp->unp_socket; 1438 solock(so); 1439 unp_scan(so->so_rcv.sb_mb, unp_discard); 1440 sounlock(so); 1441 } 1442 } 1443 } 1444 1445 unp_gcing = 0; 1446 unlock: 1447 rw_exit_write(&unp_gc_lock); 1448 } 1449 1450 void 1451 unp_dispose(struct mbuf *m) 1452 { 1453 1454 if (m) 1455 unp_scan(m, unp_discard); 1456 } 1457 1458 void 1459 unp_scan(struct mbuf *m0, void (*op)(struct fdpass *, int)) 1460 { 1461 struct mbuf *m; 1462 struct fdpass *rp; 1463 struct cmsghdr *cm; 1464 int qfds; 1465 1466 while (m0) { 1467 for (m = m0; m; m = m->m_next) { 1468 if (m->m_type == MT_CONTROL && 1469 m->m_len >= sizeof(*cm)) { 1470 cm = mtod(m, struct cmsghdr *); 1471 if (cm->cmsg_level != SOL_SOCKET || 1472 cm->cmsg_type != SCM_RIGHTS) 1473 continue; 1474 qfds = (cm->cmsg_len - CMSG_ALIGN(sizeof *cm)) 1475 / sizeof(struct fdpass); 1476 if (qfds > 0) { 1477 rp = (struct fdpass *)CMSG_DATA(cm); 1478 op(rp, qfds); 1479 } 1480 break; /* XXX, but saves time */ 1481 } 1482 } 1483 m0 = m0->m_nextpkt; 1484 } 1485 } 1486 1487 void 1488 unp_discard(struct fdpass *rp, int nfds) 1489 { 1490 struct unp_deferral *defer; 1491 1492 /* copy the file pointers to a deferral structure */ 1493 defer = malloc(sizeof(*defer) + sizeof(*rp) * nfds, M_TEMP, M_WAITOK); 1494 defer->ud_n = nfds; 1495 memcpy(&defer->ud_fp[0], rp, sizeof(*rp) * nfds); 1496 memset(rp, 0, sizeof(*rp) * nfds); 1497 1498 rw_enter_write(&unp_df_lock); 1499 SLIST_INSERT_HEAD(&unp_deferred, defer, ud_link); 1500 rw_exit_write(&unp_df_lock); 1501 1502 task_add(systqmp, &unp_gc_task); 1503 } 1504 1505 void 1506 unp_remove_gcrefs(struct fdpass *rp, int nfds) 1507 { 1508 struct unpcb *unp; 1509 int i; 1510 1511 rw_assert_wrlock(&unp_gc_lock); 1512 1513 for (i = 0; i < nfds; i++) { 1514 if (rp[i].fp == NULL) 1515 continue; 1516 if ((unp = fptounp(rp[i].fp)) == NULL) 1517 continue; 1518 if (unp->unp_gcflags & UNP_GCDEAD) { 1519 KASSERT(unp->unp_gcrefs > 0); 1520 unp->unp_gcrefs--; 1521 } 1522 } 1523 } 1524 1525 void 1526 unp_restore_gcrefs(struct fdpass *rp, int nfds) 1527 { 1528 struct unpcb *unp; 1529 int i; 1530 1531 rw_assert_wrlock(&unp_gc_lock); 1532 1533 for (i = 0; i < nfds; i++) { 1534 if (rp[i].fp == NULL) 1535 continue; 1536 if ((unp = fptounp(rp[i].fp)) == NULL) 1537 continue; 1538 if (unp->unp_gcflags & UNP_GCDEAD) { 1539 unp->unp_gcrefs++; 1540 unp_defer++; 1541 } 1542 } 1543 } 1544 1545 int 1546 unp_nam2sun(struct mbuf *nam, struct sockaddr_un **sun, size_t *pathlen) 1547 { 1548 struct sockaddr *sa = mtod(nam, struct sockaddr *); 1549 size_t size, len; 1550 1551 if (nam->m_len < offsetof(struct sockaddr, sa_data)) 1552 return EINVAL; 1553 if (sa->sa_family != AF_UNIX) 1554 return EAFNOSUPPORT; 1555 if (sa->sa_len != nam->m_len) 1556 return EINVAL; 1557 if (sa->sa_len > sizeof(struct sockaddr_un)) 1558 return EINVAL; 1559 *sun = (struct sockaddr_un *)sa; 1560 1561 /* ensure that sun_path is NUL terminated and fits */ 1562 size = (*sun)->sun_len - offsetof(struct sockaddr_un, sun_path); 1563 len = strnlen((*sun)->sun_path, size); 1564 if (len == sizeof((*sun)->sun_path)) 1565 return EINVAL; 1566 if (len == size) { 1567 if (m_trailingspace(nam) == 0) 1568 return EINVAL; 1569 nam->m_len++; 1570 (*sun)->sun_len++; 1571 (*sun)->sun_path[len] = '\0'; 1572 } 1573 if (pathlen != NULL) 1574 *pathlen = len; 1575 1576 return 0; 1577 } 1578