1 /* 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * From: @(#)uipc_usrreq.c 8.3 (Berkeley) 1/4/94 34 * $FreeBSD: src/sys/kern/uipc_usrreq.c,v 1.54.2.10 2003/03/04 17:28:09 nectar Exp $ 35 * $DragonFly: src/sys/kern/uipc_usrreq.c,v 1.44 2008/09/06 05:44:58 dillon Exp $ 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/domain.h> 42 #include <sys/fcntl.h> 43 #include <sys/malloc.h> /* XXX must be before <sys/file.h> */ 44 #include <sys/proc.h> 45 #include <sys/file.h> 46 #include <sys/filedesc.h> 47 #include <sys/mbuf.h> 48 #include <sys/nlookup.h> 49 #include <sys/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/resourcevar.h> 53 #include <sys/stat.h> 54 #include <sys/mount.h> 55 #include <sys/sysctl.h> 56 #include <sys/un.h> 57 #include <sys/unpcb.h> 58 #include <sys/vnode.h> 59 #include <sys/file2.h> 60 #include <sys/spinlock2.h> 61 62 63 static MALLOC_DEFINE(M_UNPCB, "unpcb", "unpcb struct"); 64 static unp_gen_t unp_gencnt; 65 static u_int unp_count; 66 67 static struct unp_head unp_shead, unp_dhead; 68 69 /* 70 * Unix communications domain. 71 * 72 * TODO: 73 * RDM 74 * rethink name space problems 75 * need a proper out-of-band 76 * lock pushdown 77 */ 78 static struct sockaddr sun_noname = { sizeof(sun_noname), AF_LOCAL }; 79 static ino_t unp_ino = 1; /* prototype for fake inode numbers */ 80 static struct spinlock unp_ino_spin = SPINLOCK_INITIALIZER(&unp_ino_spin); 81 82 static int unp_attach (struct socket *, struct pru_attach_info *); 83 static void unp_detach (struct unpcb *); 84 static int unp_bind (struct unpcb *,struct sockaddr *, struct thread *); 85 static int unp_connect (struct socket *,struct sockaddr *, 86 struct thread *); 87 static void unp_disconnect (struct unpcb *); 88 static void unp_shutdown (struct unpcb *); 89 static void unp_drop (struct unpcb *, int); 90 static void unp_gc (void); 91 static int unp_gc_clearmarks(struct file *, void *); 92 static int unp_gc_checkmarks(struct file *, void *); 93 static int unp_gc_checkrefs(struct file *, void *); 94 static int unp_revoke_gc_check(struct file *, void *); 95 static void unp_scan (struct mbuf *, void (*)(struct file *, void *), 96 void *data); 97 static void unp_mark (struct file *, void *data); 98 static void unp_discard (struct file *, void *); 99 static int unp_internalize (struct mbuf *, struct thread *); 100 static int unp_listen (struct unpcb *, struct thread *); 101 static void unp_fp_externalize(struct proc *p, struct file *fp, int fd); 102 103 static int 104 uipc_abort(struct socket *so) 105 { 106 struct unpcb *unp = so->so_pcb; 107 108 if (unp == NULL) 109 return EINVAL; 110 unp_drop(unp, ECONNABORTED); 111 unp_detach(unp); 112 sofree(so); 113 return 0; 114 } 115 116 static int 117 uipc_accept(struct socket *so, struct sockaddr **nam) 118 { 119 struct unpcb *unp = so->so_pcb; 120 121 if (unp == NULL) 122 return EINVAL; 123 124 /* 125 * Pass back name of connected socket, 126 * if it was bound and we are still connected 127 * (our peer may have closed already!). 128 */ 129 if (unp->unp_conn && unp->unp_conn->unp_addr) { 130 *nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr); 131 } else { 132 *nam = dup_sockaddr((struct sockaddr *)&sun_noname); 133 } 134 return 0; 135 } 136 137 static int 138 uipc_attach(struct socket *so, int proto, struct pru_attach_info *ai) 139 { 140 struct unpcb *unp = so->so_pcb; 141 142 if (unp != NULL) 143 return EISCONN; 144 return unp_attach(so, ai); 145 } 146 147 static int 148 uipc_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 149 { 150 struct unpcb *unp = so->so_pcb; 151 152 if (unp == NULL) 153 return EINVAL; 154 return unp_bind(unp, nam, td); 155 } 156 157 static int 158 uipc_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 159 { 160 struct unpcb *unp = so->so_pcb; 161 162 if (unp == NULL) 163 return EINVAL; 164 return unp_connect(so, nam, td); 165 } 166 167 static int 168 uipc_connect2(struct socket *so1, struct socket *so2) 169 { 170 struct unpcb *unp = so1->so_pcb; 171 172 if (unp == NULL) 173 return EINVAL; 174 175 return unp_connect2(so1, so2); 176 } 177 178 /* control is EOPNOTSUPP */ 179 180 static int 181 uipc_detach(struct socket *so) 182 { 183 struct unpcb *unp = so->so_pcb; 184 185 if (unp == NULL) 186 return EINVAL; 187 188 unp_detach(unp); 189 return 0; 190 } 191 192 static int 193 uipc_disconnect(struct socket *so) 194 { 195 struct unpcb *unp = so->so_pcb; 196 197 if (unp == NULL) 198 return EINVAL; 199 unp_disconnect(unp); 200 return 0; 201 } 202 203 static int 204 uipc_listen(struct socket *so, struct thread *td) 205 { 206 struct unpcb *unp = so->so_pcb; 207 208 if (unp == NULL || unp->unp_vnode == NULL) 209 return EINVAL; 210 return unp_listen(unp, td); 211 } 212 213 static int 214 uipc_peeraddr(struct socket *so, struct sockaddr **nam) 215 { 216 struct unpcb *unp = so->so_pcb; 217 218 if (unp == NULL) 219 return EINVAL; 220 if (unp->unp_conn && unp->unp_conn->unp_addr) 221 *nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr); 222 else { 223 /* 224 * XXX: It seems that this test always fails even when 225 * connection is established. So, this else clause is 226 * added as workaround to return PF_LOCAL sockaddr. 227 */ 228 *nam = dup_sockaddr((struct sockaddr *)&sun_noname); 229 } 230 return 0; 231 } 232 233 static int 234 uipc_rcvd(struct socket *so, int flags) 235 { 236 struct unpcb *unp = so->so_pcb; 237 struct socket *so2; 238 239 if (unp == NULL) 240 return EINVAL; 241 switch (so->so_type) { 242 case SOCK_DGRAM: 243 panic("uipc_rcvd DGRAM?"); 244 /*NOTREACHED*/ 245 246 case SOCK_STREAM: 247 case SOCK_SEQPACKET: 248 if (unp->unp_conn == NULL) 249 break; 250 /* 251 * Because we are transfering mbufs directly to the 252 * peer socket we have to use SSB_STOP on the sender 253 * to prevent it from building up infinite mbufs. 254 */ 255 so2 = unp->unp_conn->unp_socket; 256 if (so->so_rcv.ssb_cc < so2->so_snd.ssb_hiwat && 257 so->so_rcv.ssb_mbcnt < so2->so_snd.ssb_mbmax 258 ) { 259 so2->so_snd.ssb_flags &= ~SSB_STOP; 260 sowwakeup(so2); 261 } 262 break; 263 264 default: 265 panic("uipc_rcvd unknown socktype"); 266 } 267 return 0; 268 } 269 270 /* pru_rcvoob is EOPNOTSUPP */ 271 272 static int 273 uipc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 274 struct mbuf *control, struct thread *td) 275 { 276 int error = 0; 277 struct unpcb *unp = so->so_pcb; 278 struct socket *so2; 279 280 if (unp == NULL) { 281 error = EINVAL; 282 goto release; 283 } 284 if (flags & PRUS_OOB) { 285 error = EOPNOTSUPP; 286 goto release; 287 } 288 289 if (control && (error = unp_internalize(control, td))) 290 goto release; 291 292 switch (so->so_type) { 293 case SOCK_DGRAM: 294 { 295 struct sockaddr *from; 296 297 if (nam) { 298 if (unp->unp_conn) { 299 error = EISCONN; 300 break; 301 } 302 error = unp_connect(so, nam, td); 303 if (error) 304 break; 305 } else { 306 if (unp->unp_conn == NULL) { 307 error = ENOTCONN; 308 break; 309 } 310 } 311 so2 = unp->unp_conn->unp_socket; 312 if (unp->unp_addr) 313 from = (struct sockaddr *)unp->unp_addr; 314 else 315 from = &sun_noname; 316 if (ssb_appendaddr(&so2->so_rcv, from, m, control)) { 317 sorwakeup(so2); 318 m = NULL; 319 control = NULL; 320 } else { 321 error = ENOBUFS; 322 } 323 if (nam) 324 unp_disconnect(unp); 325 break; 326 } 327 328 case SOCK_STREAM: 329 case SOCK_SEQPACKET: 330 /* Connect if not connected yet. */ 331 /* 332 * Note: A better implementation would complain 333 * if not equal to the peer's address. 334 */ 335 if (!(so->so_state & SS_ISCONNECTED)) { 336 if (nam) { 337 error = unp_connect(so, nam, td); 338 if (error) 339 break; /* XXX */ 340 } else { 341 error = ENOTCONN; 342 break; 343 } 344 } 345 346 if (so->so_state & SS_CANTSENDMORE) { 347 error = EPIPE; 348 break; 349 } 350 if (unp->unp_conn == NULL) 351 panic("uipc_send connected but no connection?"); 352 so2 = unp->unp_conn->unp_socket; 353 /* 354 * Send to paired receive port, and then reduce 355 * send buffer hiwater marks to maintain backpressure. 356 * Wake up readers. 357 */ 358 if (control) { 359 if (ssb_appendcontrol(&so2->so_rcv, m, control)) { 360 control = NULL; 361 m = NULL; 362 } 363 } else if (so->so_type == SOCK_SEQPACKET) { 364 sbappendrecord(&so2->so_rcv.sb, m); 365 m = NULL; 366 } else { 367 sbappend(&so2->so_rcv.sb, m); 368 m = NULL; 369 } 370 371 /* 372 * Because we are transfering mbufs directly to the 373 * peer socket we have to use SSB_STOP on the sender 374 * to prevent it from building up infinite mbufs. 375 */ 376 if (so2->so_rcv.ssb_cc >= so->so_snd.ssb_hiwat || 377 so2->so_rcv.ssb_mbcnt >= so->so_snd.ssb_mbmax 378 ) { 379 so->so_snd.ssb_flags |= SSB_STOP; 380 } 381 sorwakeup(so2); 382 break; 383 384 default: 385 panic("uipc_send unknown socktype"); 386 } 387 388 /* 389 * SEND_EOF is equivalent to a SEND followed by a SHUTDOWN. 390 */ 391 if (flags & PRUS_EOF) { 392 socantsendmore(so); 393 unp_shutdown(unp); 394 } 395 396 if (control && error != 0) 397 unp_dispose(control); 398 399 release: 400 if (control) 401 m_freem(control); 402 if (m) 403 m_freem(m); 404 return error; 405 } 406 407 /* 408 * MPSAFE 409 */ 410 static int 411 uipc_sense(struct socket *so, struct stat *sb) 412 { 413 struct unpcb *unp = so->so_pcb; 414 415 if (unp == NULL) 416 return EINVAL; 417 sb->st_blksize = so->so_snd.ssb_hiwat; 418 sb->st_dev = NOUDEV; 419 if (unp->unp_ino == 0) { /* make up a non-zero inode number */ 420 spin_lock_wr(&unp_ino_spin); 421 unp->unp_ino = unp_ino++; 422 spin_unlock_wr(&unp_ino_spin); 423 } 424 sb->st_ino = unp->unp_ino; 425 return (0); 426 } 427 428 static int 429 uipc_shutdown(struct socket *so) 430 { 431 struct unpcb *unp = so->so_pcb; 432 433 if (unp == NULL) 434 return EINVAL; 435 socantsendmore(so); 436 unp_shutdown(unp); 437 return 0; 438 } 439 440 static int 441 uipc_sockaddr(struct socket *so, struct sockaddr **nam) 442 { 443 struct unpcb *unp = so->so_pcb; 444 445 if (unp == NULL) 446 return EINVAL; 447 if (unp->unp_addr) 448 *nam = dup_sockaddr((struct sockaddr *)unp->unp_addr); 449 return 0; 450 } 451 452 struct pr_usrreqs uipc_usrreqs = { 453 .pru_abort = uipc_abort, 454 .pru_accept = uipc_accept, 455 .pru_attach = uipc_attach, 456 .pru_bind = uipc_bind, 457 .pru_connect = uipc_connect, 458 .pru_connect2 = uipc_connect2, 459 .pru_control = pru_control_notsupp, 460 .pru_detach = uipc_detach, 461 .pru_disconnect = uipc_disconnect, 462 .pru_listen = uipc_listen, 463 .pru_peeraddr = uipc_peeraddr, 464 .pru_rcvd = uipc_rcvd, 465 .pru_rcvoob = pru_rcvoob_notsupp, 466 .pru_send = uipc_send, 467 .pru_sense = uipc_sense, 468 .pru_shutdown = uipc_shutdown, 469 .pru_sockaddr = uipc_sockaddr, 470 .pru_sosend = sosend, 471 .pru_soreceive = soreceive, 472 .pru_sopoll = sopoll 473 }; 474 475 int 476 uipc_ctloutput(struct socket *so, struct sockopt *sopt) 477 { 478 struct unpcb *unp = so->so_pcb; 479 int error = 0; 480 481 switch (sopt->sopt_dir) { 482 case SOPT_GET: 483 switch (sopt->sopt_name) { 484 case LOCAL_PEERCRED: 485 if (unp->unp_flags & UNP_HAVEPC) 486 soopt_from_kbuf(sopt, &unp->unp_peercred, 487 sizeof(unp->unp_peercred)); 488 else { 489 if (so->so_type == SOCK_STREAM) 490 error = ENOTCONN; 491 else if (so->so_type == SOCK_SEQPACKET) 492 error = ENOTCONN; 493 else 494 error = EINVAL; 495 } 496 break; 497 default: 498 error = EOPNOTSUPP; 499 break; 500 } 501 break; 502 case SOPT_SET: 503 default: 504 error = EOPNOTSUPP; 505 break; 506 } 507 return (error); 508 } 509 510 /* 511 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 512 * for stream sockets, although the total for sender and receiver is 513 * actually only PIPSIZ. 514 * 515 * Datagram sockets really use the sendspace as the maximum datagram size, 516 * and don't really want to reserve the sendspace. Their recvspace should 517 * be large enough for at least one max-size datagram plus address. 518 * 519 * We want the local send/recv space to be significant larger then lo0's 520 * mtu of 16384. 521 */ 522 #ifndef PIPSIZ 523 #define PIPSIZ 57344 524 #endif 525 static u_long unpst_sendspace = PIPSIZ; 526 static u_long unpst_recvspace = PIPSIZ; 527 static u_long unpdg_sendspace = 2*1024; /* really max datagram size */ 528 static u_long unpdg_recvspace = 4*1024; 529 530 static int unp_rights; /* file descriptors in flight */ 531 static struct spinlock unp_spin = SPINLOCK_INITIALIZER(&unp_spin); 532 533 SYSCTL_DECL(_net_local_seqpacket); 534 SYSCTL_DECL(_net_local_stream); 535 SYSCTL_INT(_net_local_stream, OID_AUTO, sendspace, CTLFLAG_RW, 536 &unpst_sendspace, 0, ""); 537 SYSCTL_INT(_net_local_stream, OID_AUTO, recvspace, CTLFLAG_RW, 538 &unpst_recvspace, 0, ""); 539 540 SYSCTL_DECL(_net_local_dgram); 541 SYSCTL_INT(_net_local_dgram, OID_AUTO, maxdgram, CTLFLAG_RW, 542 &unpdg_sendspace, 0, ""); 543 SYSCTL_INT(_net_local_dgram, OID_AUTO, recvspace, CTLFLAG_RW, 544 &unpdg_recvspace, 0, ""); 545 546 SYSCTL_DECL(_net_local); 547 SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0, ""); 548 549 static int 550 unp_attach(struct socket *so, struct pru_attach_info *ai) 551 { 552 struct unpcb *unp; 553 int error; 554 555 if (so->so_snd.ssb_hiwat == 0 || so->so_rcv.ssb_hiwat == 0) { 556 switch (so->so_type) { 557 558 case SOCK_STREAM: 559 case SOCK_SEQPACKET: 560 error = soreserve(so, unpst_sendspace, unpst_recvspace, 561 ai->sb_rlimit); 562 break; 563 564 case SOCK_DGRAM: 565 error = soreserve(so, unpdg_sendspace, unpdg_recvspace, 566 ai->sb_rlimit); 567 break; 568 569 default: 570 panic("unp_attach"); 571 } 572 if (error) 573 return (error); 574 } 575 unp = kmalloc(sizeof(*unp), M_UNPCB, M_NOWAIT|M_ZERO); 576 if (unp == NULL) 577 return (ENOBUFS); 578 unp->unp_gencnt = ++unp_gencnt; 579 unp_count++; 580 LIST_INIT(&unp->unp_refs); 581 unp->unp_socket = so; 582 unp->unp_rvnode = ai->fd_rdir; /* jail cruft XXX JH */ 583 LIST_INSERT_HEAD(so->so_type == SOCK_DGRAM ? &unp_dhead 584 : &unp_shead, unp, unp_link); 585 so->so_pcb = (caddr_t)unp; 586 return (0); 587 } 588 589 static void 590 unp_detach(struct unpcb *unp) 591 { 592 LIST_REMOVE(unp, unp_link); 593 unp->unp_gencnt = ++unp_gencnt; 594 --unp_count; 595 if (unp->unp_vnode) { 596 unp->unp_vnode->v_socket = NULL; 597 vrele(unp->unp_vnode); 598 unp->unp_vnode = NULL; 599 } 600 if (unp->unp_conn) 601 unp_disconnect(unp); 602 while (!LIST_EMPTY(&unp->unp_refs)) 603 unp_drop(LIST_FIRST(&unp->unp_refs), ECONNRESET); 604 soisdisconnected(unp->unp_socket); 605 unp->unp_socket->so_pcb = NULL; 606 if (unp_rights) { 607 /* 608 * Normally the receive buffer is flushed later, 609 * in sofree, but if our receive buffer holds references 610 * to descriptors that are now garbage, we will dispose 611 * of those descriptor references after the garbage collector 612 * gets them (resulting in a "panic: closef: count < 0"). 613 */ 614 sorflush(unp->unp_socket); 615 unp_gc(); 616 } 617 if (unp->unp_addr) 618 kfree(unp->unp_addr, M_SONAME); 619 kfree(unp, M_UNPCB); 620 } 621 622 static int 623 unp_bind(struct unpcb *unp, struct sockaddr *nam, struct thread *td) 624 { 625 struct proc *p = td->td_proc; 626 struct sockaddr_un *soun = (struct sockaddr_un *)nam; 627 struct vnode *vp; 628 struct vattr vattr; 629 int error, namelen; 630 struct nlookupdata nd; 631 char buf[SOCK_MAXADDRLEN]; 632 633 if (unp->unp_vnode != NULL) 634 return (EINVAL); 635 namelen = soun->sun_len - offsetof(struct sockaddr_un, sun_path); 636 if (namelen <= 0) 637 return (EINVAL); 638 strncpy(buf, soun->sun_path, namelen); 639 buf[namelen] = 0; /* null-terminate the string */ 640 error = nlookup_init(&nd, buf, UIO_SYSSPACE, 641 NLC_LOCKVP | NLC_CREATE | NLC_REFDVP); 642 if (error == 0) 643 error = nlookup(&nd); 644 if (error == 0 && nd.nl_nch.ncp->nc_vp != NULL) 645 error = EADDRINUSE; 646 if (error) 647 goto done; 648 649 VATTR_NULL(&vattr); 650 vattr.va_type = VSOCK; 651 vattr.va_mode = (ACCESSPERMS & ~p->p_fd->fd_cmask); 652 error = VOP_NCREATE(&nd.nl_nch, nd.nl_dvp, &vp, nd.nl_cred, &vattr); 653 if (error == 0) { 654 vp->v_socket = unp->unp_socket; 655 unp->unp_vnode = vp; 656 unp->unp_addr = (struct sockaddr_un *)dup_sockaddr(nam); 657 vn_unlock(vp); 658 } 659 done: 660 nlookup_done(&nd); 661 return (error); 662 } 663 664 static int 665 unp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 666 { 667 struct proc *p = td->td_proc; 668 struct sockaddr_un *soun = (struct sockaddr_un *)nam; 669 struct vnode *vp; 670 struct socket *so2, *so3; 671 struct unpcb *unp, *unp2, *unp3; 672 int error, len; 673 struct nlookupdata nd; 674 char buf[SOCK_MAXADDRLEN]; 675 676 KKASSERT(p); 677 678 len = nam->sa_len - offsetof(struct sockaddr_un, sun_path); 679 if (len <= 0) 680 return EINVAL; 681 strncpy(buf, soun->sun_path, len); 682 buf[len] = 0; 683 684 vp = NULL; 685 error = nlookup_init(&nd, buf, UIO_SYSSPACE, NLC_FOLLOW); 686 if (error == 0) 687 error = nlookup(&nd); 688 if (error == 0) 689 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp); 690 nlookup_done(&nd); 691 if (error) 692 return (error); 693 694 if (vp->v_type != VSOCK) { 695 error = ENOTSOCK; 696 goto bad; 697 } 698 error = VOP_ACCESS(vp, VWRITE, p->p_ucred); 699 if (error) 700 goto bad; 701 so2 = vp->v_socket; 702 if (so2 == NULL) { 703 error = ECONNREFUSED; 704 goto bad; 705 } 706 if (so->so_type != so2->so_type) { 707 error = EPROTOTYPE; 708 goto bad; 709 } 710 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 711 if (!(so2->so_options & SO_ACCEPTCONN) || 712 (so3 = sonewconn(so2, 0)) == NULL) { 713 error = ECONNREFUSED; 714 goto bad; 715 } 716 unp = so->so_pcb; 717 unp2 = so2->so_pcb; 718 unp3 = so3->so_pcb; 719 if (unp2->unp_addr) 720 unp3->unp_addr = (struct sockaddr_un *) 721 dup_sockaddr((struct sockaddr *)unp2->unp_addr); 722 723 /* 724 * unp_peercred management: 725 * 726 * The connecter's (client's) credentials are copied 727 * from its process structure at the time of connect() 728 * (which is now). 729 */ 730 cru2x(p->p_ucred, &unp3->unp_peercred); 731 unp3->unp_flags |= UNP_HAVEPC; 732 /* 733 * The receiver's (server's) credentials are copied 734 * from the unp_peercred member of socket on which the 735 * former called listen(); unp_listen() cached that 736 * process's credentials at that time so we can use 737 * them now. 738 */ 739 KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED, 740 ("unp_connect: listener without cached peercred")); 741 memcpy(&unp->unp_peercred, &unp2->unp_peercred, 742 sizeof(unp->unp_peercred)); 743 unp->unp_flags |= UNP_HAVEPC; 744 745 so2 = so3; 746 } 747 error = unp_connect2(so, so2); 748 bad: 749 vput(vp); 750 return (error); 751 } 752 753 int 754 unp_connect2(struct socket *so, struct socket *so2) 755 { 756 struct unpcb *unp = so->so_pcb; 757 struct unpcb *unp2; 758 759 if (so2->so_type != so->so_type) 760 return (EPROTOTYPE); 761 unp2 = so2->so_pcb; 762 unp->unp_conn = unp2; 763 switch (so->so_type) { 764 765 case SOCK_DGRAM: 766 LIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_reflink); 767 soisconnected(so); 768 break; 769 770 case SOCK_STREAM: 771 case SOCK_SEQPACKET: 772 unp2->unp_conn = unp; 773 soisconnected(so); 774 soisconnected(so2); 775 break; 776 777 default: 778 panic("unp_connect2"); 779 } 780 return (0); 781 } 782 783 static void 784 unp_disconnect(struct unpcb *unp) 785 { 786 struct unpcb *unp2 = unp->unp_conn; 787 788 if (unp2 == NULL) 789 return; 790 791 unp->unp_conn = NULL; 792 793 switch (unp->unp_socket->so_type) { 794 case SOCK_DGRAM: 795 LIST_REMOVE(unp, unp_reflink); 796 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 797 break; 798 case SOCK_STREAM: 799 case SOCK_SEQPACKET: 800 soisdisconnected(unp->unp_socket); 801 unp2->unp_conn = NULL; 802 soisdisconnected(unp2->unp_socket); 803 break; 804 } 805 } 806 807 #ifdef notdef 808 void 809 unp_abort(struct unpcb *unp) 810 { 811 812 unp_detach(unp); 813 } 814 #endif 815 816 static int 817 prison_unpcb(struct thread *td, struct unpcb *unp) 818 { 819 struct proc *p; 820 821 if (td == NULL) 822 return (0); 823 if ((p = td->td_proc) == NULL) 824 return (0); 825 if (!p->p_ucred->cr_prison) 826 return (0); 827 if (p->p_fd->fd_rdir == unp->unp_rvnode) 828 return (0); 829 return (1); 830 } 831 832 static int 833 unp_pcblist(SYSCTL_HANDLER_ARGS) 834 { 835 int error, i, n; 836 struct unpcb *unp, **unp_list; 837 unp_gen_t gencnt; 838 struct unp_head *head; 839 840 head = ((intptr_t)arg1 == SOCK_DGRAM ? &unp_dhead : &unp_shead); 841 842 KKASSERT(curproc != NULL); 843 844 /* 845 * The process of preparing the PCB list is too time-consuming and 846 * resource-intensive to repeat twice on every request. 847 */ 848 if (req->oldptr == NULL) { 849 n = unp_count; 850 req->oldidx = (n + n/8) * sizeof(struct xunpcb); 851 return 0; 852 } 853 854 if (req->newptr != NULL) 855 return EPERM; 856 857 /* 858 * OK, now we're committed to doing something. 859 */ 860 gencnt = unp_gencnt; 861 n = unp_count; 862 863 unp_list = kmalloc(n * sizeof *unp_list, M_TEMP, M_WAITOK); 864 865 for (unp = LIST_FIRST(head), i = 0; unp && i < n; 866 unp = LIST_NEXT(unp, unp_link)) { 867 if (unp->unp_gencnt <= gencnt && !prison_unpcb(req->td, unp)) 868 unp_list[i++] = unp; 869 } 870 n = i; /* in case we lost some during malloc */ 871 872 error = 0; 873 for (i = 0; i < n; i++) { 874 unp = unp_list[i]; 875 if (unp->unp_gencnt <= gencnt) { 876 struct xunpcb xu; 877 xu.xu_len = sizeof xu; 878 xu.xu_unpp = unp; 879 /* 880 * XXX - need more locking here to protect against 881 * connect/disconnect races for SMP. 882 */ 883 if (unp->unp_addr) 884 bcopy(unp->unp_addr, &xu.xu_addr, 885 unp->unp_addr->sun_len); 886 if (unp->unp_conn && unp->unp_conn->unp_addr) 887 bcopy(unp->unp_conn->unp_addr, 888 &xu.xu_caddr, 889 unp->unp_conn->unp_addr->sun_len); 890 bcopy(unp, &xu.xu_unp, sizeof *unp); 891 sotoxsocket(unp->unp_socket, &xu.xu_socket); 892 error = SYSCTL_OUT(req, &xu, sizeof xu); 893 } 894 } 895 kfree(unp_list, M_TEMP); 896 return error; 897 } 898 899 SYSCTL_PROC(_net_local_dgram, OID_AUTO, pcblist, CTLFLAG_RD, 900 (caddr_t)(long)SOCK_DGRAM, 0, unp_pcblist, "S,xunpcb", 901 "List of active local datagram sockets"); 902 SYSCTL_PROC(_net_local_stream, OID_AUTO, pcblist, CTLFLAG_RD, 903 (caddr_t)(long)SOCK_STREAM, 0, unp_pcblist, "S,xunpcb", 904 "List of active local stream sockets"); 905 SYSCTL_PROC(_net_local_seqpacket, OID_AUTO, pcblist, CTLFLAG_RD, 906 (caddr_t)(long)SOCK_SEQPACKET, 0, unp_pcblist, "S,xunpcb", 907 "List of active local seqpacket stream sockets"); 908 909 static void 910 unp_shutdown(struct unpcb *unp) 911 { 912 struct socket *so; 913 914 if ((unp->unp_socket->so_type == SOCK_STREAM || 915 unp->unp_socket->so_type == SOCK_SEQPACKET) && 916 unp->unp_conn != NULL && (so = unp->unp_conn->unp_socket)) { 917 socantrcvmore(so); 918 } 919 } 920 921 static void 922 unp_drop(struct unpcb *unp, int err) 923 { 924 struct socket *so = unp->unp_socket; 925 926 so->so_error = err; 927 unp_disconnect(unp); 928 } 929 930 #ifdef notdef 931 void 932 unp_drain(void) 933 { 934 935 } 936 #endif 937 938 int 939 unp_externalize(struct mbuf *rights) 940 { 941 struct proc *p = curproc; /* XXX */ 942 int i; 943 struct cmsghdr *cm = mtod(rights, struct cmsghdr *); 944 int *fdp; 945 struct file **rp; 946 struct file *fp; 947 int newfds = (cm->cmsg_len - (CMSG_DATA(cm) - (u_char *)cm)) 948 / sizeof (struct file *); 949 int f; 950 951 /* 952 * if the new FD's will not fit, then we free them all 953 */ 954 if (!fdavail(p, newfds)) { 955 rp = (struct file **)CMSG_DATA(cm); 956 for (i = 0; i < newfds; i++) { 957 fp = *rp; 958 /* 959 * zero the pointer before calling unp_discard, 960 * since it may end up in unp_gc().. 961 */ 962 *rp++ = 0; 963 unp_discard(fp, NULL); 964 } 965 return (EMSGSIZE); 966 } 967 968 /* 969 * now change each pointer to an fd in the global table to 970 * an integer that is the index to the local fd table entry 971 * that we set up to point to the global one we are transferring. 972 * If sizeof (struct file *) is bigger than or equal to sizeof int, 973 * then do it in forward order. In that case, an integer will 974 * always come in the same place or before its corresponding 975 * struct file pointer. 976 * If sizeof (struct file *) is smaller than sizeof int, then 977 * do it in reverse order. 978 */ 979 if (sizeof (struct file *) >= sizeof (int)) { 980 fdp = (int *)CMSG_DATA(cm); 981 rp = (struct file **)CMSG_DATA(cm); 982 for (i = 0; i < newfds; i++) { 983 if (fdalloc(p, 0, &f)) 984 panic("unp_externalize"); 985 fp = *rp++; 986 unp_fp_externalize(p, fp, f); 987 *fdp++ = f; 988 } 989 } else { 990 fdp = (int *)CMSG_DATA(cm) + newfds - 1; 991 rp = (struct file **)CMSG_DATA(cm) + newfds - 1; 992 for (i = 0; i < newfds; i++) { 993 if (fdalloc(p, 0, &f)) 994 panic("unp_externalize"); 995 fp = *rp--; 996 unp_fp_externalize(p, fp, f); 997 *fdp-- = f; 998 } 999 } 1000 1001 /* 1002 * Adjust length, in case sizeof(struct file *) and sizeof(int) 1003 * differs. 1004 */ 1005 cm->cmsg_len = CMSG_LEN(newfds * sizeof(int)); 1006 rights->m_len = cm->cmsg_len; 1007 return (0); 1008 } 1009 1010 static void 1011 unp_fp_externalize(struct proc *p, struct file *fp, int fd) 1012 { 1013 struct file *fx; 1014 int error; 1015 1016 if (p) { 1017 KKASSERT(fd >= 0); 1018 if (fp->f_flag & FREVOKED) { 1019 kprintf("Warning: revoked fp exiting unix socket\n"); 1020 fx = NULL; 1021 error = falloc(p, &fx, NULL); 1022 if (error == 0) 1023 fsetfd(p, fx, fd); 1024 else 1025 fsetfd(p, NULL, fd); 1026 fdrop(fx); 1027 } else { 1028 fsetfd(p, fp, fd); 1029 } 1030 } 1031 spin_lock_wr(&unp_spin); 1032 fp->f_msgcount--; 1033 unp_rights--; 1034 spin_unlock_wr(&unp_spin); 1035 fdrop(fp); 1036 } 1037 1038 1039 void 1040 unp_init(void) 1041 { 1042 LIST_INIT(&unp_dhead); 1043 LIST_INIT(&unp_shead); 1044 spin_init(&unp_spin); 1045 } 1046 1047 static int 1048 unp_internalize(struct mbuf *control, struct thread *td) 1049 { 1050 struct proc *p = td->td_proc; 1051 struct filedesc *fdescp; 1052 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1053 struct file **rp; 1054 struct file *fp; 1055 int i, fd, *fdp; 1056 struct cmsgcred *cmcred; 1057 int oldfds; 1058 u_int newlen; 1059 1060 KKASSERT(p); 1061 fdescp = p->p_fd; 1062 if ((cm->cmsg_type != SCM_RIGHTS && cm->cmsg_type != SCM_CREDS) || 1063 cm->cmsg_level != SOL_SOCKET || 1064 CMSG_ALIGN(cm->cmsg_len) != control->m_len) { 1065 return (EINVAL); 1066 } 1067 1068 /* 1069 * Fill in credential information. 1070 */ 1071 if (cm->cmsg_type == SCM_CREDS) { 1072 cmcred = (struct cmsgcred *)CMSG_DATA(cm); 1073 cmcred->cmcred_pid = p->p_pid; 1074 cmcred->cmcred_uid = p->p_ucred->cr_ruid; 1075 cmcred->cmcred_gid = p->p_ucred->cr_rgid; 1076 cmcred->cmcred_euid = p->p_ucred->cr_uid; 1077 cmcred->cmcred_ngroups = MIN(p->p_ucred->cr_ngroups, 1078 CMGROUP_MAX); 1079 for (i = 0; i < cmcred->cmcred_ngroups; i++) 1080 cmcred->cmcred_groups[i] = p->p_ucred->cr_groups[i]; 1081 return(0); 1082 } 1083 1084 /* 1085 * cmsghdr may not be aligned, do not allow calculation(s) to 1086 * go negative. 1087 */ 1088 if (cm->cmsg_len < CMSG_LEN(0)) 1089 return(EINVAL); 1090 1091 oldfds = (cm->cmsg_len - CMSG_LEN(0)) / sizeof (int); 1092 1093 /* 1094 * check that all the FDs passed in refer to legal OPEN files 1095 * If not, reject the entire operation. 1096 */ 1097 fdp = (int *)CMSG_DATA(cm); 1098 for (i = 0; i < oldfds; i++) { 1099 fd = *fdp++; 1100 if ((unsigned)fd >= fdescp->fd_nfiles || 1101 fdescp->fd_files[fd].fp == NULL) 1102 return (EBADF); 1103 if (fdescp->fd_files[fd].fp->f_type == DTYPE_KQUEUE) 1104 return (EOPNOTSUPP); 1105 } 1106 /* 1107 * Now replace the integer FDs with pointers to 1108 * the associated global file table entry.. 1109 * Allocate a bigger buffer as necessary. But if an cluster is not 1110 * enough, return E2BIG. 1111 */ 1112 newlen = CMSG_LEN(oldfds * sizeof(struct file *)); 1113 if (newlen > MCLBYTES) 1114 return (E2BIG); 1115 if (newlen - control->m_len > M_TRAILINGSPACE(control)) { 1116 if (control->m_flags & M_EXT) 1117 return (E2BIG); 1118 MCLGET(control, MB_WAIT); 1119 if (!(control->m_flags & M_EXT)) 1120 return (ENOBUFS); 1121 1122 /* copy the data to the cluster */ 1123 memcpy(mtod(control, char *), cm, cm->cmsg_len); 1124 cm = mtod(control, struct cmsghdr *); 1125 } 1126 1127 /* 1128 * Adjust length, in case sizeof(struct file *) and sizeof(int) 1129 * differs. 1130 */ 1131 cm->cmsg_len = newlen; 1132 control->m_len = CMSG_ALIGN(newlen); 1133 1134 /* 1135 * Transform the file descriptors into struct file pointers. 1136 * If sizeof (struct file *) is bigger than or equal to sizeof int, 1137 * then do it in reverse order so that the int won't get until 1138 * we're done. 1139 * If sizeof (struct file *) is smaller than sizeof int, then 1140 * do it in forward order. 1141 */ 1142 if (sizeof (struct file *) >= sizeof (int)) { 1143 fdp = (int *)CMSG_DATA(cm) + oldfds - 1; 1144 rp = (struct file **)CMSG_DATA(cm) + oldfds - 1; 1145 for (i = 0; i < oldfds; i++) { 1146 fp = fdescp->fd_files[*fdp--].fp; 1147 *rp-- = fp; 1148 fhold(fp); 1149 spin_lock_wr(&unp_spin); 1150 fp->f_msgcount++; 1151 unp_rights++; 1152 spin_unlock_wr(&unp_spin); 1153 } 1154 } else { 1155 fdp = (int *)CMSG_DATA(cm); 1156 rp = (struct file **)CMSG_DATA(cm); 1157 for (i = 0; i < oldfds; i++) { 1158 fp = fdescp->fd_files[*fdp++].fp; 1159 *rp++ = fp; 1160 fhold(fp); 1161 spin_lock_wr(&unp_spin); 1162 fp->f_msgcount++; 1163 unp_rights++; 1164 spin_unlock_wr(&unp_spin); 1165 } 1166 } 1167 return (0); 1168 } 1169 1170 /* 1171 * Garbage collect in-transit file descriptors that get lost due to 1172 * loops (i.e. when a socket is sent to another process over itself, 1173 * and more complex situations). 1174 * 1175 * NOT MPSAFE - TODO socket flush code and maybe closef. Rest is MPSAFE. 1176 */ 1177 1178 struct unp_gc_info { 1179 struct file **extra_ref; 1180 struct file *locked_fp; 1181 int defer; 1182 int index; 1183 int maxindex; 1184 }; 1185 1186 static void 1187 unp_gc(void) 1188 { 1189 struct unp_gc_info info; 1190 static boolean_t unp_gcing; 1191 struct file **fpp; 1192 int i; 1193 1194 spin_lock_wr(&unp_spin); 1195 if (unp_gcing) { 1196 spin_unlock_wr(&unp_spin); 1197 return; 1198 } 1199 unp_gcing = TRUE; 1200 spin_unlock_wr(&unp_spin); 1201 1202 /* 1203 * before going through all this, set all FDs to 1204 * be NOT defered and NOT externally accessible 1205 */ 1206 info.defer = 0; 1207 allfiles_scan_exclusive(unp_gc_clearmarks, NULL); 1208 do { 1209 allfiles_scan_exclusive(unp_gc_checkmarks, &info); 1210 } while (info.defer); 1211 1212 /* 1213 * We grab an extra reference to each of the file table entries 1214 * that are not otherwise accessible and then free the rights 1215 * that are stored in messages on them. 1216 * 1217 * The bug in the orginal code is a little tricky, so I'll describe 1218 * what's wrong with it here. 1219 * 1220 * It is incorrect to simply unp_discard each entry for f_msgcount 1221 * times -- consider the case of sockets A and B that contain 1222 * references to each other. On a last close of some other socket, 1223 * we trigger a gc since the number of outstanding rights (unp_rights) 1224 * is non-zero. If during the sweep phase the gc code un_discards, 1225 * we end up doing a (full) closef on the descriptor. A closef on A 1226 * results in the following chain. Closef calls soo_close, which 1227 * calls soclose. Soclose calls first (through the switch 1228 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply 1229 * returns because the previous instance had set unp_gcing, and 1230 * we return all the way back to soclose, which marks the socket 1231 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush 1232 * to free up the rights that are queued in messages on the socket A, 1233 * i.e., the reference on B. The sorflush calls via the dom_dispose 1234 * switch unp_dispose, which unp_scans with unp_discard. This second 1235 * instance of unp_discard just calls closef on B. 1236 * 1237 * Well, a similar chain occurs on B, resulting in a sorflush on B, 1238 * which results in another closef on A. Unfortunately, A is already 1239 * being closed, and the descriptor has already been marked with 1240 * SS_NOFDREF, and soclose panics at this point. 1241 * 1242 * Here, we first take an extra reference to each inaccessible 1243 * descriptor. Then, we call sorflush ourself, since we know 1244 * it is a Unix domain socket anyhow. After we destroy all the 1245 * rights carried in messages, we do a last closef to get rid 1246 * of our extra reference. This is the last close, and the 1247 * unp_detach etc will shut down the socket. 1248 * 1249 * 91/09/19, bsy@cs.cmu.edu 1250 */ 1251 info.extra_ref = kmalloc(256 * sizeof(struct file *), M_FILE, M_WAITOK); 1252 info.maxindex = 256; 1253 1254 do { 1255 /* 1256 * Look for matches 1257 */ 1258 info.index = 0; 1259 allfiles_scan_exclusive(unp_gc_checkrefs, &info); 1260 1261 /* 1262 * For each FD on our hit list, do the following two things 1263 */ 1264 for (i = info.index, fpp = info.extra_ref; --i >= 0; ++fpp) { 1265 struct file *tfp = *fpp; 1266 if (tfp->f_type == DTYPE_SOCKET && tfp->f_data != NULL) 1267 sorflush((struct socket *)(tfp->f_data)); 1268 } 1269 for (i = info.index, fpp = info.extra_ref; --i >= 0; ++fpp) 1270 closef(*fpp, NULL); 1271 } while (info.index == info.maxindex); 1272 kfree((caddr_t)info.extra_ref, M_FILE); 1273 unp_gcing = FALSE; 1274 } 1275 1276 /* 1277 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry 1278 */ 1279 static int 1280 unp_gc_checkrefs(struct file *fp, void *data) 1281 { 1282 struct unp_gc_info *info = data; 1283 1284 if (fp->f_count == 0) 1285 return(0); 1286 if (info->index == info->maxindex) 1287 return(-1); 1288 1289 /* 1290 * If all refs are from msgs, and it's not marked accessible 1291 * then it must be referenced from some unreachable cycle 1292 * of (shut-down) FDs, so include it in our 1293 * list of FDs to remove 1294 */ 1295 if (fp->f_count == fp->f_msgcount && !(fp->f_flag & FMARK)) { 1296 info->extra_ref[info->index++] = fp; 1297 fhold(fp); 1298 } 1299 return(0); 1300 } 1301 1302 /* 1303 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry 1304 */ 1305 static int 1306 unp_gc_clearmarks(struct file *fp, void *data __unused) 1307 { 1308 atomic_clear_int(&fp->f_flag, FMARK | FDEFER); 1309 return(0); 1310 } 1311 1312 /* 1313 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry 1314 */ 1315 static int 1316 unp_gc_checkmarks(struct file *fp, void *data) 1317 { 1318 struct unp_gc_info *info = data; 1319 struct socket *so; 1320 1321 /* 1322 * If the file is not open, skip it 1323 */ 1324 if (fp->f_count == 0) 1325 return(0); 1326 /* 1327 * If we already marked it as 'defer' in a 1328 * previous pass, then try process it this time 1329 * and un-mark it 1330 */ 1331 if (fp->f_flag & FDEFER) { 1332 atomic_clear_int(&fp->f_flag, FDEFER); 1333 --info->defer; 1334 } else { 1335 /* 1336 * if it's not defered, then check if it's 1337 * already marked.. if so skip it 1338 */ 1339 if (fp->f_flag & FMARK) 1340 return(0); 1341 /* 1342 * If all references are from messages 1343 * in transit, then skip it. it's not 1344 * externally accessible. 1345 */ 1346 if (fp->f_count == fp->f_msgcount) 1347 return(0); 1348 /* 1349 * If it got this far then it must be 1350 * externally accessible. 1351 */ 1352 atomic_set_int(&fp->f_flag, FMARK); 1353 } 1354 1355 /* 1356 * either it was defered, or it is externally 1357 * accessible and not already marked so. 1358 * Now check if it is possibly one of OUR sockets. 1359 */ 1360 if (fp->f_type != DTYPE_SOCKET || 1361 (so = (struct socket *)fp->f_data) == NULL) 1362 return(0); 1363 if (so->so_proto->pr_domain != &localdomain || 1364 !(so->so_proto->pr_flags & PR_RIGHTS)) 1365 return(0); 1366 #ifdef notdef 1367 if (so->so_rcv.ssb_flags & SSB_LOCK) { 1368 /* 1369 * This is problematical; it's not clear 1370 * we need to wait for the sockbuf to be 1371 * unlocked (on a uniprocessor, at least), 1372 * and it's also not clear what to do 1373 * if sbwait returns an error due to receipt 1374 * of a signal. If sbwait does return 1375 * an error, we'll go into an infinite 1376 * loop. Delete all of this for now. 1377 */ 1378 sbwait(&so->so_rcv); 1379 goto restart; 1380 } 1381 #endif 1382 /* 1383 * So, Ok, it's one of our sockets and it IS externally 1384 * accessible (or was defered). Now we look 1385 * to see if we hold any file descriptors in its 1386 * message buffers. Follow those links and mark them 1387 * as accessible too. 1388 */ 1389 info->locked_fp = fp; 1390 /* spin_lock_wr(&so->so_rcv.sb_spin); */ 1391 unp_scan(so->so_rcv.ssb_mb, unp_mark, info); 1392 /* spin_unlock_wr(&so->so_rcv.sb_spin);*/ 1393 return (0); 1394 } 1395 1396 /* 1397 * Scan all unix domain sockets and replace any revoked file pointers 1398 * found with the dummy file pointer fx. We don't worry about races 1399 * against file pointers being read out as those are handled in the 1400 * externalize code. 1401 */ 1402 1403 #define REVOKE_GC_MAXFILES 32 1404 1405 struct unp_revoke_gc_info { 1406 struct file *fx; 1407 struct file *fary[REVOKE_GC_MAXFILES]; 1408 int fcount; 1409 }; 1410 1411 void 1412 unp_revoke_gc(struct file *fx) 1413 { 1414 struct unp_revoke_gc_info info; 1415 int i; 1416 1417 info.fx = fx; 1418 do { 1419 info.fcount = 0; 1420 allfiles_scan_exclusive(unp_revoke_gc_check, &info); 1421 for (i = 0; i < info.fcount; ++i) 1422 unp_fp_externalize(NULL, info.fary[i], -1); 1423 } while (info.fcount == REVOKE_GC_MAXFILES); 1424 } 1425 1426 /* 1427 * Check for and replace revoked descriptors. 1428 * 1429 * WARNING: This routine is not allowed to block. 1430 */ 1431 static int 1432 unp_revoke_gc_check(struct file *fps, void *vinfo) 1433 { 1434 struct unp_revoke_gc_info *info = vinfo; 1435 struct file *fp; 1436 struct socket *so; 1437 struct mbuf *m0; 1438 struct mbuf *m; 1439 struct file **rp; 1440 struct cmsghdr *cm; 1441 int i; 1442 int qfds; 1443 1444 /* 1445 * Is this a unix domain socket with rights-passing abilities? 1446 */ 1447 if (fps->f_type != DTYPE_SOCKET) 1448 return (0); 1449 if ((so = (struct socket *)fps->f_data) == NULL) 1450 return(0); 1451 if (so->so_proto->pr_domain != &localdomain) 1452 return(0); 1453 if ((so->so_proto->pr_flags & PR_RIGHTS) == 0) 1454 return(0); 1455 1456 /* 1457 * Scan the mbufs for control messages and replace any revoked 1458 * descriptors we find. 1459 */ 1460 m0 = so->so_rcv.ssb_mb; 1461 while (m0) { 1462 for (m = m0; m; m = m->m_next) { 1463 if (m->m_type != MT_CONTROL) 1464 continue; 1465 if (m->m_len < sizeof(*cm)) 1466 continue; 1467 cm = mtod(m, struct cmsghdr *); 1468 if (cm->cmsg_level != SOL_SOCKET || 1469 cm->cmsg_type != SCM_RIGHTS) { 1470 continue; 1471 } 1472 qfds = (cm->cmsg_len - CMSG_LEN(0)) / sizeof(void *); 1473 rp = (struct file **)CMSG_DATA(cm); 1474 for (i = 0; i < qfds; i++) { 1475 fp = rp[i]; 1476 if (fp->f_flag & FREVOKED) { 1477 kprintf("Warning: Removing revoked fp from unix domain socket queue\n"); 1478 fhold(info->fx); 1479 info->fx->f_msgcount++; 1480 unp_rights++; 1481 rp[i] = info->fx; 1482 info->fary[info->fcount++] = fp; 1483 } 1484 if (info->fcount == REVOKE_GC_MAXFILES) 1485 break; 1486 } 1487 if (info->fcount == REVOKE_GC_MAXFILES) 1488 break; 1489 } 1490 m0 = m0->m_nextpkt; 1491 if (info->fcount == REVOKE_GC_MAXFILES) 1492 break; 1493 } 1494 1495 /* 1496 * Stop the scan if we filled up our array. 1497 */ 1498 if (info->fcount == REVOKE_GC_MAXFILES) 1499 return(-1); 1500 return(0); 1501 } 1502 1503 void 1504 unp_dispose(struct mbuf *m) 1505 { 1506 if (m) 1507 unp_scan(m, unp_discard, NULL); 1508 } 1509 1510 static int 1511 unp_listen(struct unpcb *unp, struct thread *td) 1512 { 1513 struct proc *p = td->td_proc; 1514 1515 KKASSERT(p); 1516 cru2x(p->p_ucred, &unp->unp_peercred); 1517 unp->unp_flags |= UNP_HAVEPCCACHED; 1518 return (0); 1519 } 1520 1521 static void 1522 unp_scan(struct mbuf *m0, void (*op)(struct file *, void *), void *data) 1523 { 1524 struct mbuf *m; 1525 struct file **rp; 1526 struct cmsghdr *cm; 1527 int i; 1528 int qfds; 1529 1530 while (m0) { 1531 for (m = m0; m; m = m->m_next) { 1532 if (m->m_type == MT_CONTROL && 1533 m->m_len >= sizeof(*cm)) { 1534 cm = mtod(m, struct cmsghdr *); 1535 if (cm->cmsg_level != SOL_SOCKET || 1536 cm->cmsg_type != SCM_RIGHTS) 1537 continue; 1538 qfds = (cm->cmsg_len - CMSG_LEN(0)) / 1539 sizeof(void *); 1540 rp = (struct file **)CMSG_DATA(cm); 1541 for (i = 0; i < qfds; i++) 1542 (*op)(*rp++, data); 1543 break; /* XXX, but saves time */ 1544 } 1545 } 1546 m0 = m0->m_nextpkt; 1547 } 1548 } 1549 1550 static void 1551 unp_mark(struct file *fp, void *data) 1552 { 1553 struct unp_gc_info *info = data; 1554 1555 if ((fp->f_flag & FMARK) == 0) { 1556 ++info->defer; 1557 atomic_set_int(&fp->f_flag, FMARK | FDEFER); 1558 } 1559 } 1560 1561 static void 1562 unp_discard(struct file *fp, void *data __unused) 1563 { 1564 spin_lock_wr(&unp_spin); 1565 fp->f_msgcount--; 1566 unp_rights--; 1567 spin_unlock_wr(&unp_spin); 1568 closef(fp, NULL); 1569 } 1570 1571