1 /* $OpenBSD: uipc_usrreq.c,v 1.201 2024/03/17 19:47:08 mvs 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_flags & (UNP_BINDING | UNP_CONNECTING)) 419 return (EINVAL); 420 if (unp->unp_vnode == NULL) 421 return (EINVAL); 422 return (0); 423 } 424 425 int 426 uipc_connect(struct socket *so, struct mbuf *nam) 427 { 428 return unp_connect(so, nam, curproc); 429 } 430 431 int 432 uipc_accept(struct socket *so, struct mbuf *nam) 433 { 434 struct socket *so2; 435 struct unpcb *unp = sotounpcb(so); 436 437 /* 438 * Pass back name of connected socket, if it was bound and 439 * we are still connected (our peer may have closed already!). 440 */ 441 so2 = unp_solock_peer(so); 442 uipc_setaddr(unp->unp_conn, nam); 443 444 if (so2 != NULL && so2 != so) 445 sounlock(so2); 446 return (0); 447 } 448 449 int 450 uipc_disconnect(struct socket *so) 451 { 452 struct unpcb *unp = sotounpcb(so); 453 454 unp_disconnect(unp); 455 return (0); 456 } 457 458 int 459 uipc_shutdown(struct socket *so) 460 { 461 struct unpcb *unp = sotounpcb(so); 462 struct socket *so2; 463 464 socantsendmore(so); 465 466 if ((so2 = unp_solock_peer(unp->unp_socket))){ 467 socantrcvmore(so2); 468 sounlock(so2); 469 } 470 471 return (0); 472 } 473 474 int 475 uipc_dgram_shutdown(struct socket *so) 476 { 477 socantsendmore(so); 478 return (0); 479 } 480 481 void 482 uipc_rcvd(struct socket *so) 483 { 484 struct socket *so2; 485 486 if ((so2 = unp_solock_peer(so)) == NULL) 487 return; 488 /* 489 * Adjust backpressure on sender 490 * and wakeup any waiting to write. 491 */ 492 so2->so_snd.sb_mbcnt = so->so_rcv.sb_mbcnt; 493 so2->so_snd.sb_cc = so->so_rcv.sb_cc; 494 sowwakeup(so2); 495 sounlock(so2); 496 } 497 498 int 499 uipc_send(struct socket *so, struct mbuf *m, struct mbuf *nam, 500 struct mbuf *control) 501 { 502 struct socket *so2; 503 int error = 0; 504 505 if (control) { 506 sounlock(so); 507 error = unp_internalize(control, curproc); 508 solock(so); 509 if (error) 510 goto out; 511 } 512 513 if (so->so_snd.sb_state & SS_CANTSENDMORE) { 514 error = EPIPE; 515 goto dispose; 516 } 517 if ((so2 = unp_solock_peer(so)) == NULL) { 518 error = ENOTCONN; 519 goto dispose; 520 } 521 522 /* 523 * Send to paired receive port, and then raise 524 * send buffer counts to maintain backpressure. 525 * Wake up readers. 526 */ 527 if (control) { 528 if (sbappendcontrol(so2, &so2->so_rcv, m, control)) { 529 control = NULL; 530 } else { 531 sounlock(so2); 532 error = ENOBUFS; 533 goto dispose; 534 } 535 } else if (so->so_type == SOCK_SEQPACKET) 536 sbappendrecord(so2, &so2->so_rcv, m); 537 else 538 sbappend(so2, &so2->so_rcv, m); 539 so->so_snd.sb_mbcnt = so2->so_rcv.sb_mbcnt; 540 so->so_snd.sb_cc = so2->so_rcv.sb_cc; 541 if (so2->so_rcv.sb_cc > 0) 542 sorwakeup(so2); 543 544 sounlock(so2); 545 m = NULL; 546 547 dispose: 548 /* we need to undo unp_internalize in case of errors */ 549 if (control && error) 550 unp_dispose(control); 551 552 out: 553 m_freem(control); 554 m_freem(m); 555 556 return (error); 557 } 558 559 int 560 uipc_dgram_send(struct socket *so, struct mbuf *m, struct mbuf *nam, 561 struct mbuf *control) 562 { 563 struct unpcb *unp = sotounpcb(so); 564 struct socket *so2; 565 const struct sockaddr *from; 566 int error = 0; 567 568 if (control) { 569 sounlock(so); 570 error = unp_internalize(control, curproc); 571 solock(so); 572 if (error) 573 goto out; 574 } 575 576 if (nam) { 577 if (unp->unp_conn) { 578 error = EISCONN; 579 goto dispose; 580 } 581 error = unp_connect(so, nam, curproc); 582 if (error) 583 goto dispose; 584 } 585 586 if ((so2 = unp_solock_peer(so)) == NULL) { 587 if (nam != NULL) 588 error = ECONNREFUSED; 589 else 590 error = ENOTCONN; 591 goto dispose; 592 } 593 594 if (unp->unp_addr) 595 from = mtod(unp->unp_addr, struct sockaddr *); 596 else 597 from = &sun_noname; 598 if (sbappendaddr(so2, &so2->so_rcv, from, m, control)) { 599 sorwakeup(so2); 600 m = NULL; 601 control = NULL; 602 } else 603 error = ENOBUFS; 604 605 if (so2 != so) 606 sounlock(so2); 607 608 if (nam) 609 unp_disconnect(unp); 610 611 dispose: 612 /* we need to undo unp_internalize in case of errors */ 613 if (control && error) 614 unp_dispose(control); 615 616 out: 617 m_freem(control); 618 m_freem(m); 619 620 return (error); 621 } 622 623 void 624 uipc_abort(struct socket *so) 625 { 626 struct unpcb *unp = sotounpcb(so); 627 628 unp_detach(unp); 629 sofree(so, 0); 630 } 631 632 int 633 uipc_sense(struct socket *so, struct stat *sb) 634 { 635 struct unpcb *unp = sotounpcb(so); 636 637 sb->st_blksize = so->so_snd.sb_hiwat; 638 sb->st_dev = NODEV; 639 mtx_enter(&unp_ino_mtx); 640 if (unp->unp_ino == 0) 641 unp->unp_ino = unp_ino++; 642 mtx_leave(&unp_ino_mtx); 643 sb->st_atim.tv_sec = 644 sb->st_mtim.tv_sec = 645 sb->st_ctim.tv_sec = unp->unp_ctime.tv_sec; 646 sb->st_atim.tv_nsec = 647 sb->st_mtim.tv_nsec = 648 sb->st_ctim.tv_nsec = unp->unp_ctime.tv_nsec; 649 sb->st_ino = unp->unp_ino; 650 651 return (0); 652 } 653 654 int 655 uipc_sockaddr(struct socket *so, struct mbuf *nam) 656 { 657 struct unpcb *unp = sotounpcb(so); 658 659 uipc_setaddr(unp, nam); 660 return (0); 661 } 662 663 int 664 uipc_peeraddr(struct socket *so, struct mbuf *nam) 665 { 666 struct unpcb *unp = sotounpcb(so); 667 struct socket *so2; 668 669 so2 = unp_solock_peer(so); 670 uipc_setaddr(unp->unp_conn, nam); 671 if (so2 != NULL && so2 != so) 672 sounlock(so2); 673 return (0); 674 } 675 676 int 677 uipc_connect2(struct socket *so, struct socket *so2) 678 { 679 struct unpcb *unp = sotounpcb(so), *unp2; 680 int error; 681 682 if ((error = unp_connect2(so, so2))) 683 return (error); 684 685 unp->unp_connid.uid = curproc->p_ucred->cr_uid; 686 unp->unp_connid.gid = curproc->p_ucred->cr_gid; 687 unp->unp_connid.pid = curproc->p_p->ps_pid; 688 unp->unp_flags |= UNP_FEIDS; 689 unp2 = sotounpcb(so2); 690 unp2->unp_connid.uid = curproc->p_ucred->cr_uid; 691 unp2->unp_connid.gid = curproc->p_ucred->cr_gid; 692 unp2->unp_connid.pid = curproc->p_p->ps_pid; 693 unp2->unp_flags |= UNP_FEIDS; 694 695 return (0); 696 } 697 698 int 699 uipc_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, 700 size_t newlen) 701 { 702 int *valp = &unp_defer; 703 704 /* All sysctl names at this level are terminal. */ 705 switch (name[0]) { 706 case SOCK_STREAM: 707 if (namelen != 2) 708 return (ENOTDIR); 709 return sysctl_bounded_arr(unpstctl_vars, nitems(unpstctl_vars), 710 name + 1, namelen - 1, oldp, oldlenp, newp, newlen); 711 case SOCK_SEQPACKET: 712 if (namelen != 2) 713 return (ENOTDIR); 714 return sysctl_bounded_arr(unpsqctl_vars, nitems(unpsqctl_vars), 715 name + 1, namelen - 1, oldp, oldlenp, newp, newlen); 716 case SOCK_DGRAM: 717 if (namelen != 2) 718 return (ENOTDIR); 719 return sysctl_bounded_arr(unpdgctl_vars, nitems(unpdgctl_vars), 720 name + 1, namelen - 1, oldp, oldlenp, newp, newlen); 721 case NET_UNIX_INFLIGHT: 722 valp = &unp_rights; 723 /* FALLTHROUGH */ 724 case NET_UNIX_DEFERRED: 725 if (namelen != 1) 726 return (ENOTDIR); 727 return sysctl_rdint(oldp, oldlenp, newp, *valp); 728 default: 729 return (ENOPROTOOPT); 730 } 731 } 732 733 void 734 unp_detach(struct unpcb *unp) 735 { 736 struct socket *so = unp->unp_socket; 737 struct vnode *vp = unp->unp_vnode; 738 struct unpcb *unp2; 739 740 unp->unp_vnode = NULL; 741 742 /* 743 * Enforce `unp_gc_lock' -> `solock()' lock order. 744 * Enforce `i_lock' -> `solock()' lock order. 745 */ 746 sounlock(so); 747 748 rw_enter_write(&unp_gc_lock); 749 LIST_REMOVE(unp, unp_link); 750 rw_exit_write(&unp_gc_lock); 751 752 if (vp != NULL) { 753 VOP_LOCK(vp, LK_EXCLUSIVE); 754 vp->v_socket = NULL; 755 756 KERNEL_LOCK(); 757 vput(vp); 758 KERNEL_UNLOCK(); 759 } 760 761 solock(so); 762 763 if (unp->unp_conn != NULL) { 764 /* 765 * Datagram socket could be connected to itself. 766 * Such socket will be disconnected here. 767 */ 768 unp_disconnect(unp); 769 } 770 771 while ((unp2 = SLIST_FIRST(&unp->unp_refs)) != NULL) { 772 struct socket *so2 = unp2->unp_socket; 773 774 if (so < so2) 775 solock(so2); 776 else { 777 unp_ref(unp2); 778 sounlock(so); 779 solock(so2); 780 solock(so); 781 782 if (unp2->unp_conn != unp) { 783 /* `unp2' was disconnected due to re-lock. */ 784 sounlock(so2); 785 unp_rele(unp2); 786 continue; 787 } 788 789 unp_rele(unp2); 790 } 791 792 unp2->unp_conn = NULL; 793 SLIST_REMOVE(&unp->unp_refs, unp2, unpcb, unp_nextref); 794 so2->so_error = ECONNRESET; 795 so2->so_state &= ~SS_ISCONNECTED; 796 797 sounlock(so2); 798 } 799 800 sounlock(so); 801 refcnt_finalize(&unp->unp_refcnt, "unpfinal"); 802 solock(so); 803 804 soisdisconnected(so); 805 so->so_pcb = NULL; 806 m_freem(unp->unp_addr); 807 pool_put(&unpcb_pool, unp); 808 if (unp_rights) 809 task_add(systqmp, &unp_gc_task); 810 } 811 812 int 813 unp_connect(struct socket *so, struct mbuf *nam, struct proc *p) 814 { 815 struct sockaddr_un *soun; 816 struct vnode *vp; 817 struct socket *so2, *so3; 818 struct unpcb *unp, *unp2, *unp3; 819 struct nameidata nd; 820 int error; 821 822 unp = sotounpcb(so); 823 if (unp->unp_flags & (UNP_BINDING | UNP_CONNECTING)) 824 return (EISCONN); 825 if ((error = unp_nam2sun(nam, &soun, NULL))) 826 return (error); 827 828 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, soun->sun_path, p); 829 nd.ni_pledge = PLEDGE_UNIX; 830 nd.ni_unveil = UNVEIL_WRITE; 831 832 unp->unp_flags |= UNP_CONNECTING; 833 834 /* 835 * Enforce `i_lock' -> `solock' because fifo subsystem 836 * requires it. The socket can't be closed concurrently 837 * because the file descriptor reference is still held. 838 */ 839 840 sounlock(so); 841 842 KERNEL_LOCK(); 843 error = namei(&nd); 844 if (error != 0) 845 goto unlock; 846 vp = nd.ni_vp; 847 if (vp->v_type != VSOCK) { 848 error = ENOTSOCK; 849 goto put; 850 } 851 if ((error = VOP_ACCESS(vp, VWRITE, p->p_ucred, p)) != 0) 852 goto put; 853 so2 = vp->v_socket; 854 if (so2 == NULL) { 855 error = ECONNREFUSED; 856 goto put; 857 } 858 if (so->so_type != so2->so_type) { 859 error = EPROTOTYPE; 860 goto put; 861 } 862 863 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 864 solock(so2); 865 866 if ((so2->so_options & SO_ACCEPTCONN) == 0 || 867 (so3 = sonewconn(so2, 0, M_WAIT)) == NULL) { 868 error = ECONNREFUSED; 869 } 870 871 sounlock(so2); 872 873 if (error != 0) 874 goto put; 875 876 /* 877 * Since `so2' is protected by vnode(9) lock, `so3' 878 * can't be PRU_ABORT'ed here. 879 */ 880 solock_pair(so, so3); 881 882 unp2 = sotounpcb(so2); 883 unp3 = sotounpcb(so3); 884 885 /* 886 * `unp_addr', `unp_connid' and 'UNP_FEIDSBIND' flag 887 * are immutable since we set them in uipc_bind(). 888 */ 889 if (unp2->unp_addr) 890 unp3->unp_addr = 891 m_copym(unp2->unp_addr, 0, M_COPYALL, M_NOWAIT); 892 unp3->unp_connid.uid = p->p_ucred->cr_uid; 893 unp3->unp_connid.gid = p->p_ucred->cr_gid; 894 unp3->unp_connid.pid = p->p_p->ps_pid; 895 unp3->unp_flags |= UNP_FEIDS; 896 897 if (unp2->unp_flags & UNP_FEIDSBIND) { 898 unp->unp_connid = unp2->unp_connid; 899 unp->unp_flags |= UNP_FEIDS; 900 } 901 902 so2 = so3; 903 } else { 904 if (so2 != so) 905 solock_pair(so, so2); 906 else 907 solock(so); 908 } 909 910 error = unp_connect2(so, so2); 911 912 sounlock(so); 913 914 /* 915 * `so2' can't be PRU_ABORT'ed concurrently 916 */ 917 if (so2 != so) 918 sounlock(so2); 919 put: 920 vput(vp); 921 unlock: 922 KERNEL_UNLOCK(); 923 solock(so); 924 unp->unp_flags &= ~UNP_CONNECTING; 925 926 /* 927 * The peer socket could be closed by concurrent thread 928 * when `so' and `vp' are unlocked. 929 */ 930 if (error == 0 && unp->unp_conn == NULL) 931 error = ECONNREFUSED; 932 933 return (error); 934 } 935 936 int 937 unp_connect2(struct socket *so, struct socket *so2) 938 { 939 struct unpcb *unp = sotounpcb(so); 940 struct unpcb *unp2; 941 942 soassertlocked(so); 943 soassertlocked(so2); 944 945 if (so2->so_type != so->so_type) 946 return (EPROTOTYPE); 947 unp2 = sotounpcb(so2); 948 unp->unp_conn = unp2; 949 switch (so->so_type) { 950 951 case SOCK_DGRAM: 952 SLIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_nextref); 953 soisconnected(so); 954 break; 955 956 case SOCK_STREAM: 957 case SOCK_SEQPACKET: 958 unp2->unp_conn = unp; 959 soisconnected(so); 960 soisconnected(so2); 961 break; 962 963 default: 964 panic("unp_connect2"); 965 } 966 return (0); 967 } 968 969 void 970 unp_disconnect(struct unpcb *unp) 971 { 972 struct socket *so2; 973 struct unpcb *unp2; 974 975 if ((so2 = unp_solock_peer(unp->unp_socket)) == NULL) 976 return; 977 978 unp2 = unp->unp_conn; 979 unp->unp_conn = NULL; 980 981 switch (unp->unp_socket->so_type) { 982 983 case SOCK_DGRAM: 984 SLIST_REMOVE(&unp2->unp_refs, unp, unpcb, unp_nextref); 985 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 986 break; 987 988 case SOCK_STREAM: 989 case SOCK_SEQPACKET: 990 unp->unp_socket->so_snd.sb_mbcnt = 0; 991 unp->unp_socket->so_snd.sb_cc = 0; 992 soisdisconnected(unp->unp_socket); 993 unp2->unp_conn = NULL; 994 unp2->unp_socket->so_snd.sb_mbcnt = 0; 995 unp2->unp_socket->so_snd.sb_cc = 0; 996 soisdisconnected(unp2->unp_socket); 997 break; 998 } 999 1000 if (so2 != unp->unp_socket) 1001 sounlock(so2); 1002 } 1003 1004 static struct unpcb * 1005 fptounp(struct file *fp) 1006 { 1007 struct socket *so; 1008 1009 if (fp->f_type != DTYPE_SOCKET) 1010 return (NULL); 1011 if ((so = fp->f_data) == NULL) 1012 return (NULL); 1013 if (so->so_proto->pr_domain != &unixdomain) 1014 return (NULL); 1015 return (sotounpcb(so)); 1016 } 1017 1018 int 1019 unp_externalize(struct mbuf *rights, socklen_t controllen, int flags) 1020 { 1021 struct proc *p = curproc; /* XXX */ 1022 struct cmsghdr *cm = mtod(rights, struct cmsghdr *); 1023 struct filedesc *fdp = p->p_fd; 1024 int i, *fds = NULL; 1025 struct fdpass *rp; 1026 struct file *fp; 1027 int nfds, error = 0; 1028 1029 /* 1030 * This code only works because SCM_RIGHTS is the only supported 1031 * control message type on unix sockets. Enforce this here. 1032 */ 1033 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET) 1034 return EINVAL; 1035 1036 nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) / 1037 sizeof(struct fdpass); 1038 if (controllen < CMSG_ALIGN(sizeof(struct cmsghdr))) 1039 controllen = 0; 1040 else 1041 controllen -= CMSG_ALIGN(sizeof(struct cmsghdr)); 1042 if (nfds > controllen / sizeof(int)) { 1043 error = EMSGSIZE; 1044 goto out; 1045 } 1046 1047 /* Make sure the recipient should be able to see the descriptors.. */ 1048 rp = (struct fdpass *)CMSG_DATA(cm); 1049 1050 /* fdp->fd_rdir requires KERNEL_LOCK() */ 1051 KERNEL_LOCK(); 1052 1053 for (i = 0; i < nfds; i++) { 1054 fp = rp->fp; 1055 rp++; 1056 error = pledge_recvfd(p, fp); 1057 if (error) 1058 break; 1059 1060 /* 1061 * No to block devices. If passing a directory, 1062 * make sure that it is underneath the root. 1063 */ 1064 if (fdp->fd_rdir != NULL && fp->f_type == DTYPE_VNODE) { 1065 struct vnode *vp = (struct vnode *)fp->f_data; 1066 1067 if (vp->v_type == VBLK || 1068 (vp->v_type == VDIR && 1069 !vn_isunder(vp, fdp->fd_rdir, p))) { 1070 error = EPERM; 1071 break; 1072 } 1073 } 1074 } 1075 1076 KERNEL_UNLOCK(); 1077 1078 if (error) 1079 goto out; 1080 1081 fds = mallocarray(nfds, sizeof(int), M_TEMP, M_WAITOK); 1082 1083 fdplock(fdp); 1084 restart: 1085 /* 1086 * First loop -- allocate file descriptor table slots for the 1087 * new descriptors. 1088 */ 1089 rp = ((struct fdpass *)CMSG_DATA(cm)); 1090 for (i = 0; i < nfds; i++) { 1091 if ((error = fdalloc(p, 0, &fds[i])) != 0) { 1092 /* 1093 * Back out what we've done so far. 1094 */ 1095 for (--i; i >= 0; i--) 1096 fdremove(fdp, fds[i]); 1097 1098 if (error == ENOSPC) { 1099 fdexpand(p); 1100 goto restart; 1101 } 1102 1103 fdpunlock(fdp); 1104 1105 /* 1106 * This is the error that has historically 1107 * been returned, and some callers may 1108 * expect it. 1109 */ 1110 1111 error = EMSGSIZE; 1112 goto out; 1113 } 1114 1115 /* 1116 * Make the slot reference the descriptor so that 1117 * fdalloc() works properly.. We finalize it all 1118 * in the loop below. 1119 */ 1120 mtx_enter(&fdp->fd_fplock); 1121 KASSERT(fdp->fd_ofiles[fds[i]] == NULL); 1122 fdp->fd_ofiles[fds[i]] = rp->fp; 1123 mtx_leave(&fdp->fd_fplock); 1124 1125 fdp->fd_ofileflags[fds[i]] = (rp->flags & UF_PLEDGED); 1126 if (flags & MSG_CMSG_CLOEXEC) 1127 fdp->fd_ofileflags[fds[i]] |= UF_EXCLOSE; 1128 1129 rp++; 1130 } 1131 1132 /* 1133 * Keep `fdp' locked to prevent concurrent close() of just 1134 * inserted descriptors. Such descriptors could have the only 1135 * `f_count' reference which is now shared between control 1136 * message and `fdp'. 1137 */ 1138 1139 /* 1140 * Now that adding them has succeeded, update all of the 1141 * descriptor passing state. 1142 */ 1143 rp = (struct fdpass *)CMSG_DATA(cm); 1144 1145 for (i = 0; i < nfds; i++) { 1146 struct unpcb *unp; 1147 1148 fp = rp->fp; 1149 rp++; 1150 if ((unp = fptounp(fp)) != NULL) { 1151 rw_enter_write(&unp_gc_lock); 1152 unp->unp_msgcount--; 1153 rw_exit_write(&unp_gc_lock); 1154 } 1155 } 1156 fdpunlock(fdp); 1157 1158 mtx_enter(&unp_rights_mtx); 1159 unp_rights -= nfds; 1160 mtx_leave(&unp_rights_mtx); 1161 1162 /* 1163 * Copy temporary array to message and adjust length, in case of 1164 * transition from large struct file pointers to ints. 1165 */ 1166 memcpy(CMSG_DATA(cm), fds, nfds * sizeof(int)); 1167 cm->cmsg_len = CMSG_LEN(nfds * sizeof(int)); 1168 rights->m_len = CMSG_LEN(nfds * sizeof(int)); 1169 out: 1170 if (fds != NULL) 1171 free(fds, M_TEMP, nfds * sizeof(int)); 1172 1173 if (error) { 1174 if (nfds > 0) { 1175 /* 1176 * No lock required. We are the only `cm' holder. 1177 */ 1178 rp = ((struct fdpass *)CMSG_DATA(cm)); 1179 unp_discard(rp, nfds); 1180 } 1181 } 1182 1183 return (error); 1184 } 1185 1186 int 1187 unp_internalize(struct mbuf *control, struct proc *p) 1188 { 1189 struct filedesc *fdp = p->p_fd; 1190 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1191 struct fdpass *rp; 1192 struct file *fp; 1193 struct unpcb *unp; 1194 int i, error; 1195 int nfds, *ip, fd, neededspace; 1196 1197 /* 1198 * Check for two potential msg_controllen values because 1199 * IETF stuck their nose in a place it does not belong. 1200 */ 1201 if (control->m_len < CMSG_LEN(0) || cm->cmsg_len < CMSG_LEN(0)) 1202 return (EINVAL); 1203 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET || 1204 !(cm->cmsg_len == control->m_len || 1205 control->m_len == CMSG_ALIGN(cm->cmsg_len))) 1206 return (EINVAL); 1207 nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) / sizeof (int); 1208 1209 mtx_enter(&unp_rights_mtx); 1210 if (unp_rights + nfds > maxfiles / 10) { 1211 mtx_leave(&unp_rights_mtx); 1212 return (EMFILE); 1213 } 1214 unp_rights += nfds; 1215 mtx_leave(&unp_rights_mtx); 1216 1217 /* Make sure we have room for the struct file pointers */ 1218 morespace: 1219 neededspace = CMSG_SPACE(nfds * sizeof(struct fdpass)) - 1220 control->m_len; 1221 if (neededspace > m_trailingspace(control)) { 1222 char *tmp; 1223 /* if we already have a cluster, the message is just too big */ 1224 if (control->m_flags & M_EXT) { 1225 error = E2BIG; 1226 goto nospace; 1227 } 1228 1229 /* copy cmsg data temporarily out of the mbuf */ 1230 tmp = malloc(control->m_len, M_TEMP, M_WAITOK); 1231 memcpy(tmp, mtod(control, caddr_t), control->m_len); 1232 1233 /* allocate a cluster and try again */ 1234 MCLGET(control, M_WAIT); 1235 if ((control->m_flags & M_EXT) == 0) { 1236 free(tmp, M_TEMP, control->m_len); 1237 error = ENOBUFS; /* allocation failed */ 1238 goto nospace; 1239 } 1240 1241 /* copy the data back into the cluster */ 1242 cm = mtod(control, struct cmsghdr *); 1243 memcpy(cm, tmp, control->m_len); 1244 free(tmp, M_TEMP, control->m_len); 1245 goto morespace; 1246 } 1247 1248 /* adjust message & mbuf to note amount of space actually used. */ 1249 cm->cmsg_len = CMSG_LEN(nfds * sizeof(struct fdpass)); 1250 control->m_len = CMSG_SPACE(nfds * sizeof(struct fdpass)); 1251 1252 ip = ((int *)CMSG_DATA(cm)) + nfds - 1; 1253 rp = ((struct fdpass *)CMSG_DATA(cm)) + nfds - 1; 1254 fdplock(fdp); 1255 for (i = 0; i < nfds; i++) { 1256 memcpy(&fd, ip, sizeof fd); 1257 ip--; 1258 if ((fp = fd_getfile(fdp, fd)) == NULL) { 1259 error = EBADF; 1260 goto fail; 1261 } 1262 if (fp->f_count >= FDUP_MAX_COUNT) { 1263 error = EDEADLK; 1264 goto fail; 1265 } 1266 error = pledge_sendfd(p, fp); 1267 if (error) 1268 goto fail; 1269 1270 /* kqueue descriptors cannot be copied */ 1271 if (fp->f_type == DTYPE_KQUEUE) { 1272 error = EINVAL; 1273 goto fail; 1274 } 1275 #if NKCOV > 0 1276 /* kcov descriptors cannot be copied */ 1277 if (fp->f_type == DTYPE_VNODE && kcov_vnode(fp->f_data)) { 1278 error = EINVAL; 1279 goto fail; 1280 } 1281 #endif 1282 rp->fp = fp; 1283 rp->flags = fdp->fd_ofileflags[fd] & UF_PLEDGED; 1284 rp--; 1285 if ((unp = fptounp(fp)) != NULL) { 1286 rw_enter_write(&unp_gc_lock); 1287 unp->unp_msgcount++; 1288 unp->unp_file = fp; 1289 rw_exit_write(&unp_gc_lock); 1290 } 1291 } 1292 fdpunlock(fdp); 1293 return (0); 1294 fail: 1295 fdpunlock(fdp); 1296 if (fp != NULL) 1297 FRELE(fp, p); 1298 /* Back out what we just did. */ 1299 for ( ; i > 0; i--) { 1300 rp++; 1301 fp = rp->fp; 1302 if ((unp = fptounp(fp)) != NULL) { 1303 rw_enter_write(&unp_gc_lock); 1304 unp->unp_msgcount--; 1305 rw_exit_write(&unp_gc_lock); 1306 } 1307 FRELE(fp, p); 1308 } 1309 1310 nospace: 1311 mtx_enter(&unp_rights_mtx); 1312 unp_rights -= nfds; 1313 mtx_leave(&unp_rights_mtx); 1314 1315 return (error); 1316 } 1317 1318 void 1319 unp_gc(void *arg __unused) 1320 { 1321 struct unp_deferral *defer; 1322 struct file *fp; 1323 struct socket *so; 1324 struct unpcb *unp; 1325 int nunref, i; 1326 1327 rw_enter_write(&unp_gc_lock); 1328 if (unp_gcing) 1329 goto unlock; 1330 unp_gcing = 1; 1331 rw_exit_write(&unp_gc_lock); 1332 1333 rw_enter_write(&unp_df_lock); 1334 /* close any fds on the deferred list */ 1335 while ((defer = SLIST_FIRST(&unp_deferred)) != NULL) { 1336 SLIST_REMOVE_HEAD(&unp_deferred, ud_link); 1337 rw_exit_write(&unp_df_lock); 1338 for (i = 0; i < defer->ud_n; i++) { 1339 fp = defer->ud_fp[i].fp; 1340 if (fp == NULL) 1341 continue; 1342 if ((unp = fptounp(fp)) != NULL) { 1343 rw_enter_write(&unp_gc_lock); 1344 unp->unp_msgcount--; 1345 rw_exit_write(&unp_gc_lock); 1346 } 1347 mtx_enter(&unp_rights_mtx); 1348 unp_rights--; 1349 mtx_leave(&unp_rights_mtx); 1350 /* closef() expects a refcount of 2 */ 1351 FREF(fp); 1352 (void) closef(fp, NULL); 1353 } 1354 free(defer, M_TEMP, sizeof(*defer) + 1355 sizeof(struct fdpass) * defer->ud_n); 1356 rw_enter_write(&unp_df_lock); 1357 } 1358 rw_exit_write(&unp_df_lock); 1359 1360 nunref = 0; 1361 1362 rw_enter_write(&unp_gc_lock); 1363 1364 /* 1365 * Determine sockets which may be prospectively dead. Such 1366 * sockets have their `unp_msgcount' equal to the `f_count'. 1367 * If `unp_msgcount' is 0, the socket has not been passed 1368 * and can't be unreferenced. 1369 */ 1370 LIST_FOREACH(unp, &unp_head, unp_link) { 1371 unp->unp_gcflags = 0; 1372 1373 if (unp->unp_msgcount == 0) 1374 continue; 1375 if ((fp = unp->unp_file) == NULL) 1376 continue; 1377 if (fp->f_count == unp->unp_msgcount) { 1378 unp->unp_gcflags |= UNP_GCDEAD; 1379 unp->unp_gcrefs = unp->unp_msgcount; 1380 nunref++; 1381 } 1382 } 1383 1384 /* 1385 * Scan all sockets previously marked as dead. Remove 1386 * the `unp_gcrefs' reference each socket holds on any 1387 * dead socket in its buffer. 1388 */ 1389 LIST_FOREACH(unp, &unp_head, unp_link) { 1390 if ((unp->unp_gcflags & UNP_GCDEAD) == 0) 1391 continue; 1392 so = unp->unp_socket; 1393 solock(so); 1394 unp_scan(so->so_rcv.sb_mb, unp_remove_gcrefs); 1395 sounlock(so); 1396 } 1397 1398 /* 1399 * If the dead socket has `unp_gcrefs' reference counter 1400 * greater than 0, it can't be unreferenced. Mark it as 1401 * alive and increment the `unp_gcrefs' reference for each 1402 * dead socket within its buffer. Repeat this until we 1403 * have no new alive sockets found. 1404 */ 1405 do { 1406 unp_defer = 0; 1407 1408 LIST_FOREACH(unp, &unp_head, unp_link) { 1409 if ((unp->unp_gcflags & UNP_GCDEAD) == 0) 1410 continue; 1411 if (unp->unp_gcrefs == 0) 1412 continue; 1413 1414 unp->unp_gcflags &= ~UNP_GCDEAD; 1415 1416 so = unp->unp_socket; 1417 solock(so); 1418 unp_scan(so->so_rcv.sb_mb, unp_restore_gcrefs); 1419 sounlock(so); 1420 1421 KASSERT(nunref > 0); 1422 nunref--; 1423 } 1424 } while (unp_defer > 0); 1425 1426 /* 1427 * If there are any unreferenced sockets, then for each dispose 1428 * of files in its receive buffer and then close it. 1429 */ 1430 if (nunref) { 1431 LIST_FOREACH(unp, &unp_head, unp_link) { 1432 if (unp->unp_gcflags & UNP_GCDEAD) { 1433 /* 1434 * This socket could still be connected 1435 * and if so it's `so_rcv' is still 1436 * accessible by concurrent PRU_SEND 1437 * thread. 1438 */ 1439 so = unp->unp_socket; 1440 solock(so); 1441 unp_scan(so->so_rcv.sb_mb, unp_discard); 1442 sounlock(so); 1443 } 1444 } 1445 } 1446 1447 unp_gcing = 0; 1448 unlock: 1449 rw_exit_write(&unp_gc_lock); 1450 } 1451 1452 void 1453 unp_dispose(struct mbuf *m) 1454 { 1455 1456 if (m) 1457 unp_scan(m, unp_discard); 1458 } 1459 1460 void 1461 unp_scan(struct mbuf *m0, void (*op)(struct fdpass *, int)) 1462 { 1463 struct mbuf *m; 1464 struct fdpass *rp; 1465 struct cmsghdr *cm; 1466 int qfds; 1467 1468 while (m0) { 1469 for (m = m0; m; m = m->m_next) { 1470 if (m->m_type == MT_CONTROL && 1471 m->m_len >= sizeof(*cm)) { 1472 cm = mtod(m, struct cmsghdr *); 1473 if (cm->cmsg_level != SOL_SOCKET || 1474 cm->cmsg_type != SCM_RIGHTS) 1475 continue; 1476 qfds = (cm->cmsg_len - CMSG_ALIGN(sizeof *cm)) 1477 / sizeof(struct fdpass); 1478 if (qfds > 0) { 1479 rp = (struct fdpass *)CMSG_DATA(cm); 1480 op(rp, qfds); 1481 } 1482 break; /* XXX, but saves time */ 1483 } 1484 } 1485 m0 = m0->m_nextpkt; 1486 } 1487 } 1488 1489 void 1490 unp_discard(struct fdpass *rp, int nfds) 1491 { 1492 struct unp_deferral *defer; 1493 1494 /* copy the file pointers to a deferral structure */ 1495 defer = malloc(sizeof(*defer) + sizeof(*rp) * nfds, M_TEMP, M_WAITOK); 1496 defer->ud_n = nfds; 1497 memcpy(&defer->ud_fp[0], rp, sizeof(*rp) * nfds); 1498 memset(rp, 0, sizeof(*rp) * nfds); 1499 1500 rw_enter_write(&unp_df_lock); 1501 SLIST_INSERT_HEAD(&unp_deferred, defer, ud_link); 1502 rw_exit_write(&unp_df_lock); 1503 1504 task_add(systqmp, &unp_gc_task); 1505 } 1506 1507 void 1508 unp_remove_gcrefs(struct fdpass *rp, int nfds) 1509 { 1510 struct unpcb *unp; 1511 int i; 1512 1513 rw_assert_wrlock(&unp_gc_lock); 1514 1515 for (i = 0; i < nfds; i++) { 1516 if (rp[i].fp == NULL) 1517 continue; 1518 if ((unp = fptounp(rp[i].fp)) == NULL) 1519 continue; 1520 if (unp->unp_gcflags & UNP_GCDEAD) { 1521 KASSERT(unp->unp_gcrefs > 0); 1522 unp->unp_gcrefs--; 1523 } 1524 } 1525 } 1526 1527 void 1528 unp_restore_gcrefs(struct fdpass *rp, int nfds) 1529 { 1530 struct unpcb *unp; 1531 int i; 1532 1533 rw_assert_wrlock(&unp_gc_lock); 1534 1535 for (i = 0; i < nfds; i++) { 1536 if (rp[i].fp == NULL) 1537 continue; 1538 if ((unp = fptounp(rp[i].fp)) == NULL) 1539 continue; 1540 if (unp->unp_gcflags & UNP_GCDEAD) { 1541 unp->unp_gcrefs++; 1542 unp_defer++; 1543 } 1544 } 1545 } 1546 1547 int 1548 unp_nam2sun(struct mbuf *nam, struct sockaddr_un **sun, size_t *pathlen) 1549 { 1550 struct sockaddr *sa = mtod(nam, struct sockaddr *); 1551 size_t size, len; 1552 1553 if (nam->m_len < offsetof(struct sockaddr, sa_data)) 1554 return EINVAL; 1555 if (sa->sa_family != AF_UNIX) 1556 return EAFNOSUPPORT; 1557 if (sa->sa_len != nam->m_len) 1558 return EINVAL; 1559 if (sa->sa_len > sizeof(struct sockaddr_un)) 1560 return EINVAL; 1561 *sun = (struct sockaddr_un *)sa; 1562 1563 /* ensure that sun_path is NUL terminated and fits */ 1564 size = (*sun)->sun_len - offsetof(struct sockaddr_un, sun_path); 1565 len = strnlen((*sun)->sun_path, size); 1566 if (len == sizeof((*sun)->sun_path)) 1567 return EINVAL; 1568 if (len == size) { 1569 if (m_trailingspace(nam) == 0) 1570 return EINVAL; 1571 nam->m_len++; 1572 (*sun)->sun_len++; 1573 (*sun)->sun_path[len] = '\0'; 1574 } 1575 if (pathlen != NULL) 1576 *pathlen = len; 1577 1578 return 0; 1579 } 1580