1 /* 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)uipc_usrreq.c 8.4 (Berkeley) 08/11/94 8 */ 9 10 #include <sys/param.h> 11 #include <sys/systm.h> 12 #include <sys/proc.h> 13 #include <sys/filedesc.h> 14 #include <sys/domain.h> 15 #include <sys/protosw.h> 16 #include <sys/socket.h> 17 #include <sys/socketvar.h> 18 #include <sys/unpcb.h> 19 #include <sys/un.h> 20 #include <sys/namei.h> 21 #include <sys/vnode.h> 22 #include <sys/file.h> 23 #include <sys/stat.h> 24 #include <sys/mbuf.h> 25 26 /* 27 * Unix communications domain. 28 * 29 * TODO: 30 * SEQPACKET, RDM 31 * rethink name space problems 32 * need a proper out-of-band 33 */ 34 struct sockaddr sun_noname = { sizeof(sun_noname), AF_UNIX }; 35 ino_t unp_ino; /* prototype for fake inode numbers */ 36 37 /*ARGSUSED*/ 38 uipc_usrreq(so, req, m, nam, control) 39 struct socket *so; 40 int req; 41 struct mbuf *m, *nam, *control; 42 { 43 struct unpcb *unp = sotounpcb(so); 44 register struct socket *so2; 45 register int error = 0; 46 struct proc *p = curproc; /* XXX */ 47 48 if (req == PRU_CONTROL) 49 return (EOPNOTSUPP); 50 if (req != PRU_SEND && control && control->m_len) { 51 error = EOPNOTSUPP; 52 goto release; 53 } 54 if (unp == 0 && req != PRU_ATTACH) { 55 error = EINVAL; 56 goto release; 57 } 58 switch (req) { 59 60 case PRU_ATTACH: 61 if (unp) { 62 error = EISCONN; 63 break; 64 } 65 error = unp_attach(so); 66 break; 67 68 case PRU_DETACH: 69 unp_detach(unp); 70 break; 71 72 case PRU_BIND: 73 error = unp_bind(unp, nam, p); 74 break; 75 76 case PRU_LISTEN: 77 if (unp->unp_vnode == 0) 78 error = EINVAL; 79 break; 80 81 case PRU_CONNECT: 82 error = unp_connect(so, nam, p); 83 break; 84 85 case PRU_CONNECT2: 86 error = unp_connect2(so, (struct socket *)nam); 87 break; 88 89 case PRU_DISCONNECT: 90 unp_disconnect(unp); 91 break; 92 93 case PRU_ACCEPT: 94 /* 95 * Pass back name of connected socket, 96 * if it was bound and we are still connected 97 * (our peer may have closed already!). 98 */ 99 if (unp->unp_conn && unp->unp_conn->unp_addr) { 100 nam->m_len = unp->unp_conn->unp_addr->m_len; 101 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 102 mtod(nam, caddr_t), (unsigned)nam->m_len); 103 } else { 104 nam->m_len = sizeof(sun_noname); 105 *(mtod(nam, struct sockaddr *)) = sun_noname; 106 } 107 break; 108 109 case PRU_SHUTDOWN: 110 socantsendmore(so); 111 unp_shutdown(unp); 112 break; 113 114 case PRU_RCVD: 115 switch (so->so_type) { 116 117 case SOCK_DGRAM: 118 panic("uipc 1"); 119 /*NOTREACHED*/ 120 121 case SOCK_STREAM: 122 #define rcv (&so->so_rcv) 123 #define snd (&so2->so_snd) 124 if (unp->unp_conn == 0) 125 break; 126 so2 = unp->unp_conn->unp_socket; 127 /* 128 * Adjust backpressure on sender 129 * and wakeup any waiting to write. 130 */ 131 snd->sb_mbmax += unp->unp_mbcnt - rcv->sb_mbcnt; 132 unp->unp_mbcnt = rcv->sb_mbcnt; 133 snd->sb_hiwat += unp->unp_cc - rcv->sb_cc; 134 unp->unp_cc = rcv->sb_cc; 135 sowwakeup(so2); 136 #undef snd 137 #undef rcv 138 break; 139 140 default: 141 panic("uipc 2"); 142 } 143 break; 144 145 case PRU_SEND: 146 if (control && (error = unp_internalize(control, p))) 147 break; 148 switch (so->so_type) { 149 150 case SOCK_DGRAM: { 151 struct sockaddr *from; 152 153 if (nam) { 154 if (unp->unp_conn) { 155 error = EISCONN; 156 break; 157 } 158 error = unp_connect(so, nam, p); 159 if (error) 160 break; 161 } else { 162 if (unp->unp_conn == 0) { 163 error = ENOTCONN; 164 break; 165 } 166 } 167 so2 = unp->unp_conn->unp_socket; 168 if (unp->unp_addr) 169 from = mtod(unp->unp_addr, struct sockaddr *); 170 else 171 from = &sun_noname; 172 if (sbappendaddr(&so2->so_rcv, from, m, control)) { 173 sorwakeup(so2); 174 m = 0; 175 control = 0; 176 } else 177 error = ENOBUFS; 178 if (nam) 179 unp_disconnect(unp); 180 break; 181 } 182 183 case SOCK_STREAM: 184 #define rcv (&so2->so_rcv) 185 #define snd (&so->so_snd) 186 if (so->so_state & SS_CANTSENDMORE) { 187 error = EPIPE; 188 break; 189 } 190 if (unp->unp_conn == 0) 191 panic("uipc 3"); 192 so2 = unp->unp_conn->unp_socket; 193 /* 194 * Send to paired receive port, and then reduce 195 * send buffer hiwater marks to maintain backpressure. 196 * Wake up readers. 197 */ 198 if (control) { 199 if (sbappendcontrol(rcv, m, control)) 200 control = 0; 201 } else 202 sbappend(rcv, m); 203 snd->sb_mbmax -= 204 rcv->sb_mbcnt - unp->unp_conn->unp_mbcnt; 205 unp->unp_conn->unp_mbcnt = rcv->sb_mbcnt; 206 snd->sb_hiwat -= rcv->sb_cc - unp->unp_conn->unp_cc; 207 unp->unp_conn->unp_cc = rcv->sb_cc; 208 sorwakeup(so2); 209 m = 0; 210 #undef snd 211 #undef rcv 212 break; 213 214 default: 215 panic("uipc 4"); 216 } 217 break; 218 219 case PRU_ABORT: 220 unp_drop(unp, ECONNABORTED); 221 break; 222 223 case PRU_SENSE: 224 ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat; 225 if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) { 226 so2 = unp->unp_conn->unp_socket; 227 ((struct stat *) m)->st_blksize += so2->so_rcv.sb_cc; 228 } 229 ((struct stat *) m)->st_dev = NODEV; 230 if (unp->unp_ino == 0) 231 unp->unp_ino = unp_ino++; 232 ((struct stat *) m)->st_ino = unp->unp_ino; 233 return (0); 234 235 case PRU_RCVOOB: 236 return (EOPNOTSUPP); 237 238 case PRU_SENDOOB: 239 error = EOPNOTSUPP; 240 break; 241 242 case PRU_SOCKADDR: 243 if (unp->unp_addr) { 244 nam->m_len = unp->unp_addr->m_len; 245 bcopy(mtod(unp->unp_addr, caddr_t), 246 mtod(nam, caddr_t), (unsigned)nam->m_len); 247 } else 248 nam->m_len = 0; 249 break; 250 251 case PRU_PEERADDR: 252 if (unp->unp_conn && unp->unp_conn->unp_addr) { 253 nam->m_len = unp->unp_conn->unp_addr->m_len; 254 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 255 mtod(nam, caddr_t), (unsigned)nam->m_len); 256 } else 257 nam->m_len = 0; 258 break; 259 260 case PRU_SLOWTIMO: 261 break; 262 263 default: 264 panic("piusrreq"); 265 } 266 release: 267 if (control) 268 m_freem(control); 269 if (m) 270 m_freem(m); 271 return (error); 272 } 273 274 /* 275 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 276 * for stream sockets, although the total for sender and receiver is 277 * actually only PIPSIZ. 278 * Datagram sockets really use the sendspace as the maximum datagram size, 279 * and don't really want to reserve the sendspace. Their recvspace should 280 * be large enough for at least one max-size datagram plus address. 281 */ 282 #define PIPSIZ 4096 283 u_long unpst_sendspace = PIPSIZ; 284 u_long unpst_recvspace = PIPSIZ; 285 u_long unpdg_sendspace = 2*1024; /* really max datagram size */ 286 u_long unpdg_recvspace = 4*1024; 287 288 int unp_rights; /* file descriptors in flight */ 289 290 unp_attach(so) 291 struct socket *so; 292 { 293 register struct mbuf *m; 294 register struct unpcb *unp; 295 int error; 296 297 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 298 switch (so->so_type) { 299 300 case SOCK_STREAM: 301 error = soreserve(so, unpst_sendspace, unpst_recvspace); 302 break; 303 304 case SOCK_DGRAM: 305 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 306 break; 307 308 default: 309 panic("unp_attach"); 310 } 311 if (error) 312 return (error); 313 } 314 m = m_getclr(M_DONTWAIT, MT_PCB); 315 if (m == NULL) 316 return (ENOBUFS); 317 unp = mtod(m, struct unpcb *); 318 so->so_pcb = (caddr_t)unp; 319 unp->unp_socket = so; 320 return (0); 321 } 322 323 unp_detach(unp) 324 register struct unpcb *unp; 325 { 326 327 if (unp->unp_vnode) { 328 unp->unp_vnode->v_socket = 0; 329 vrele(unp->unp_vnode); 330 unp->unp_vnode = 0; 331 } 332 if (unp->unp_conn) 333 unp_disconnect(unp); 334 while (unp->unp_refs) 335 unp_drop(unp->unp_refs, ECONNRESET); 336 soisdisconnected(unp->unp_socket); 337 unp->unp_socket->so_pcb = 0; 338 m_freem(unp->unp_addr); 339 (void) m_free(dtom(unp)); 340 if (unp_rights) { 341 /* 342 * Normally the receive buffer is flushed later, 343 * in sofree, but if our receive buffer holds references 344 * to descriptors that are now garbage, we will dispose 345 * of those descriptor references after the garbage collector 346 * gets them (resulting in a "panic: closef: count < 0"). 347 */ 348 sorflush(unp->unp_socket); 349 unp_gc(); 350 } 351 } 352 353 unp_bind(unp, nam, p) 354 struct unpcb *unp; 355 struct mbuf *nam; 356 struct proc *p; 357 { 358 struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 359 register struct vnode *vp; 360 struct vattr vattr; 361 int error; 362 struct nameidata nd; 363 364 NDINIT(&nd, CREATE, FOLLOW | LOCKPARENT, UIO_SYSSPACE, 365 soun->sun_path, p); 366 if (unp->unp_vnode != NULL) 367 return (EINVAL); 368 if (nam->m_len == MLEN) { 369 if (*(mtod(nam, caddr_t) + nam->m_len - 1) != 0) 370 return (EINVAL); 371 } else 372 *(mtod(nam, caddr_t) + nam->m_len) = 0; 373 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 374 if (error = namei(&nd)) 375 return (error); 376 vp = nd.ni_vp; 377 if (vp != NULL) { 378 VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd); 379 if (nd.ni_dvp == vp) 380 vrele(nd.ni_dvp); 381 else 382 vput(nd.ni_dvp); 383 vrele(vp); 384 return (EADDRINUSE); 385 } 386 VATTR_NULL(&vattr); 387 vattr.va_type = VSOCK; 388 vattr.va_mode = ACCESSPERMS; 389 VOP_LEASE(nd.ni_dvp, p, p->p_ucred, LEASE_WRITE); 390 if (error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr)) 391 return (error); 392 vp = nd.ni_vp; 393 vp->v_socket = unp->unp_socket; 394 unp->unp_vnode = vp; 395 unp->unp_addr = m_copy(nam, 0, (int)M_COPYALL); 396 VOP_UNLOCK(vp); 397 return (0); 398 } 399 400 unp_connect(so, nam, p) 401 struct socket *so; 402 struct mbuf *nam; 403 struct proc *p; 404 { 405 register struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 406 register struct vnode *vp; 407 register struct socket *so2, *so3; 408 struct unpcb *unp2, *unp3; 409 int error; 410 struct nameidata nd; 411 412 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, soun->sun_path, p); 413 if (nam->m_data + nam->m_len == &nam->m_dat[MLEN]) { /* XXX */ 414 if (*(mtod(nam, caddr_t) + nam->m_len - 1) != 0) 415 return (EMSGSIZE); 416 } else 417 *(mtod(nam, caddr_t) + nam->m_len) = 0; 418 if (error = namei(&nd)) 419 return (error); 420 vp = nd.ni_vp; 421 if (vp->v_type != VSOCK) { 422 error = ENOTSOCK; 423 goto bad; 424 } 425 if (error = VOP_ACCESS(vp, VWRITE, p->p_ucred, p)) 426 goto bad; 427 so2 = vp->v_socket; 428 if (so2 == 0) { 429 error = ECONNREFUSED; 430 goto bad; 431 } 432 if (so->so_type != so2->so_type) { 433 error = EPROTOTYPE; 434 goto bad; 435 } 436 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 437 if ((so2->so_options & SO_ACCEPTCONN) == 0 || 438 (so3 = sonewconn(so2, 0)) == 0) { 439 error = ECONNREFUSED; 440 goto bad; 441 } 442 unp2 = sotounpcb(so2); 443 unp3 = sotounpcb(so3); 444 if (unp2->unp_addr) 445 unp3->unp_addr = 446 m_copy(unp2->unp_addr, 0, (int)M_COPYALL); 447 so2 = so3; 448 } 449 error = unp_connect2(so, so2); 450 bad: 451 vput(vp); 452 return (error); 453 } 454 455 unp_connect2(so, so2) 456 register struct socket *so; 457 register struct socket *so2; 458 { 459 register struct unpcb *unp = sotounpcb(so); 460 register struct unpcb *unp2; 461 462 if (so2->so_type != so->so_type) 463 return (EPROTOTYPE); 464 unp2 = sotounpcb(so2); 465 unp->unp_conn = unp2; 466 switch (so->so_type) { 467 468 case SOCK_DGRAM: 469 unp->unp_nextref = unp2->unp_refs; 470 unp2->unp_refs = unp; 471 soisconnected(so); 472 break; 473 474 case SOCK_STREAM: 475 unp2->unp_conn = unp; 476 soisconnected(so); 477 soisconnected(so2); 478 break; 479 480 default: 481 panic("unp_connect2"); 482 } 483 return (0); 484 } 485 486 unp_disconnect(unp) 487 struct unpcb *unp; 488 { 489 register struct unpcb *unp2 = unp->unp_conn; 490 491 if (unp2 == 0) 492 return; 493 unp->unp_conn = 0; 494 switch (unp->unp_socket->so_type) { 495 496 case SOCK_DGRAM: 497 if (unp2->unp_refs == unp) 498 unp2->unp_refs = unp->unp_nextref; 499 else { 500 unp2 = unp2->unp_refs; 501 for (;;) { 502 if (unp2 == 0) 503 panic("unp_disconnect"); 504 if (unp2->unp_nextref == unp) 505 break; 506 unp2 = unp2->unp_nextref; 507 } 508 unp2->unp_nextref = unp->unp_nextref; 509 } 510 unp->unp_nextref = 0; 511 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 512 break; 513 514 case SOCK_STREAM: 515 soisdisconnected(unp->unp_socket); 516 unp2->unp_conn = 0; 517 soisdisconnected(unp2->unp_socket); 518 break; 519 } 520 } 521 522 #ifdef notdef 523 unp_abort(unp) 524 struct unpcb *unp; 525 { 526 527 unp_detach(unp); 528 } 529 #endif 530 531 unp_shutdown(unp) 532 struct unpcb *unp; 533 { 534 struct socket *so; 535 536 if (unp->unp_socket->so_type == SOCK_STREAM && unp->unp_conn && 537 (so = unp->unp_conn->unp_socket)) 538 socantrcvmore(so); 539 } 540 541 unp_drop(unp, errno) 542 struct unpcb *unp; 543 int errno; 544 { 545 struct socket *so = unp->unp_socket; 546 547 so->so_error = errno; 548 unp_disconnect(unp); 549 if (so->so_head) { 550 so->so_pcb = (caddr_t) 0; 551 m_freem(unp->unp_addr); 552 (void) m_free(dtom(unp)); 553 sofree(so); 554 } 555 } 556 557 #ifdef notdef 558 unp_drain() 559 { 560 561 } 562 #endif 563 564 unp_externalize(rights) 565 struct mbuf *rights; 566 { 567 struct proc *p = curproc; /* XXX */ 568 register int i; 569 register struct cmsghdr *cm = mtod(rights, struct cmsghdr *); 570 register struct file **rp = (struct file **)(cm + 1); 571 register struct file *fp; 572 int newfds = (cm->cmsg_len - sizeof(*cm)) / sizeof (int); 573 int f; 574 575 if (!fdavail(p, newfds)) { 576 for (i = 0; i < newfds; i++) { 577 fp = *rp; 578 unp_discard(fp); 579 *rp++ = 0; 580 } 581 return (EMSGSIZE); 582 } 583 for (i = 0; i < newfds; i++) { 584 if (fdalloc(p, 0, &f)) 585 panic("unp_externalize"); 586 fp = *rp; 587 p->p_fd->fd_ofiles[f] = fp; 588 fp->f_msgcount--; 589 unp_rights--; 590 *(int *)rp++ = f; 591 } 592 return (0); 593 } 594 595 unp_internalize(control, p) 596 struct mbuf *control; 597 struct proc *p; 598 { 599 struct filedesc *fdp = p->p_fd; 600 register struct cmsghdr *cm = mtod(control, struct cmsghdr *); 601 register struct file **rp; 602 register struct file *fp; 603 register int i, fd; 604 int oldfds; 605 606 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET || 607 cm->cmsg_len != control->m_len) 608 return (EINVAL); 609 oldfds = (cm->cmsg_len - sizeof (*cm)) / sizeof (int); 610 rp = (struct file **)(cm + 1); 611 for (i = 0; i < oldfds; i++) { 612 fd = *(int *)rp++; 613 if ((unsigned)fd >= fdp->fd_nfiles || 614 fdp->fd_ofiles[fd] == NULL) 615 return (EBADF); 616 } 617 rp = (struct file **)(cm + 1); 618 for (i = 0; i < oldfds; i++) { 619 fp = fdp->fd_ofiles[*(int *)rp]; 620 *rp++ = fp; 621 fp->f_count++; 622 fp->f_msgcount++; 623 unp_rights++; 624 } 625 return (0); 626 } 627 628 int unp_defer, unp_gcing; 629 int unp_mark(); 630 extern struct domain unixdomain; 631 632 unp_gc() 633 { 634 register struct file *fp, *nextfp; 635 register struct socket *so; 636 struct file **extra_ref, **fpp; 637 int nunref, i; 638 639 if (unp_gcing) 640 return; 641 unp_gcing = 1; 642 unp_defer = 0; 643 for (fp = filehead; fp; fp = fp->f_filef) 644 fp->f_flag &= ~(FMARK|FDEFER); 645 do { 646 for (fp = filehead; fp; fp = fp->f_filef) { 647 if (fp->f_count == 0) 648 continue; 649 if (fp->f_flag & FDEFER) { 650 fp->f_flag &= ~FDEFER; 651 unp_defer--; 652 } else { 653 if (fp->f_flag & FMARK) 654 continue; 655 if (fp->f_count == fp->f_msgcount) 656 continue; 657 fp->f_flag |= FMARK; 658 } 659 if (fp->f_type != DTYPE_SOCKET || 660 (so = (struct socket *)fp->f_data) == 0) 661 continue; 662 if (so->so_proto->pr_domain != &unixdomain || 663 (so->so_proto->pr_flags&PR_RIGHTS) == 0) 664 continue; 665 #ifdef notdef 666 if (so->so_rcv.sb_flags & SB_LOCK) { 667 /* 668 * This is problematical; it's not clear 669 * we need to wait for the sockbuf to be 670 * unlocked (on a uniprocessor, at least), 671 * and it's also not clear what to do 672 * if sbwait returns an error due to receipt 673 * of a signal. If sbwait does return 674 * an error, we'll go into an infinite 675 * loop. Delete all of this for now. 676 */ 677 (void) sbwait(&so->so_rcv); 678 goto restart; 679 } 680 #endif 681 unp_scan(so->so_rcv.sb_mb, unp_mark); 682 } 683 } while (unp_defer); 684 /* 685 * We grab an extra reference to each of the file table entries 686 * that are not otherwise accessible and then free the rights 687 * that are stored in messages on them. 688 * 689 * The bug in the orginal code is a little tricky, so I'll describe 690 * what's wrong with it here. 691 * 692 * It is incorrect to simply unp_discard each entry for f_msgcount 693 * times -- consider the case of sockets A and B that contain 694 * references to each other. On a last close of some other socket, 695 * we trigger a gc since the number of outstanding rights (unp_rights) 696 * is non-zero. If during the sweep phase the gc code un_discards, 697 * we end up doing a (full) closef on the descriptor. A closef on A 698 * results in the following chain. Closef calls soo_close, which 699 * calls soclose. Soclose calls first (through the switch 700 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply 701 * returns because the previous instance had set unp_gcing, and 702 * we return all the way back to soclose, which marks the socket 703 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush 704 * to free up the rights that are queued in messages on the socket A, 705 * i.e., the reference on B. The sorflush calls via the dom_dispose 706 * switch unp_dispose, which unp_scans with unp_discard. This second 707 * instance of unp_discard just calls closef on B. 708 * 709 * Well, a similar chain occurs on B, resulting in a sorflush on B, 710 * which results in another closef on A. Unfortunately, A is already 711 * being closed, and the descriptor has already been marked with 712 * SS_NOFDREF, and soclose panics at this point. 713 * 714 * Here, we first take an extra reference to each inaccessible 715 * descriptor. Then, we call sorflush ourself, since we know 716 * it is a Unix domain socket anyhow. After we destroy all the 717 * rights carried in messages, we do a last closef to get rid 718 * of our extra reference. This is the last close, and the 719 * unp_detach etc will shut down the socket. 720 * 721 * 91/09/19, bsy@cs.cmu.edu 722 */ 723 extra_ref = malloc(nfiles * sizeof(struct file *), M_FILE, M_WAITOK); 724 for (nunref = 0, fp = filehead, fpp = extra_ref; fp; fp = nextfp) { 725 nextfp = fp->f_filef; 726 if (fp->f_count == 0) 727 continue; 728 if (fp->f_count == fp->f_msgcount && !(fp->f_flag & FMARK)) { 729 *fpp++ = fp; 730 nunref++; 731 fp->f_count++; 732 } 733 } 734 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp) 735 sorflush((struct socket *)(*fpp)->f_data); 736 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp) 737 closef(*fpp); 738 free((caddr_t)extra_ref, M_FILE); 739 unp_gcing = 0; 740 } 741 742 unp_dispose(m) 743 struct mbuf *m; 744 { 745 int unp_discard(); 746 747 if (m) 748 unp_scan(m, unp_discard); 749 } 750 751 unp_scan(m0, op) 752 register struct mbuf *m0; 753 int (*op)(); 754 { 755 register struct mbuf *m; 756 register struct file **rp; 757 register struct cmsghdr *cm; 758 register int i; 759 int qfds; 760 761 while (m0) { 762 for (m = m0; m; m = m->m_next) 763 if (m->m_type == MT_CONTROL && 764 m->m_len >= sizeof(*cm)) { 765 cm = mtod(m, struct cmsghdr *); 766 if (cm->cmsg_level != SOL_SOCKET || 767 cm->cmsg_type != SCM_RIGHTS) 768 continue; 769 qfds = (cm->cmsg_len - sizeof *cm) 770 / sizeof (struct file *); 771 rp = (struct file **)(cm + 1); 772 for (i = 0; i < qfds; i++) 773 (*op)(*rp++); 774 break; /* XXX, but saves time */ 775 } 776 m0 = m0->m_act; 777 } 778 } 779 780 unp_mark(fp) 781 struct file *fp; 782 { 783 784 if (fp->f_flag & FMARK) 785 return; 786 unp_defer++; 787 fp->f_flag |= (FMARK|FDEFER); 788 } 789 790 unp_discard(fp) 791 struct file *fp; 792 { 793 794 fp->f_msgcount--; 795 unp_rights--; 796 (void) closef(fp, (struct proc *)NULL); 797 } 798