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sys/kern/uipc_usrreq.c
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1 /* $NetBSD: uipc_usrreq.c,v 1.74.2.1 2005/07/18 04:03:05 riz Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 /* 41 * Copyright (c) 1982, 1986, 1989, 1991, 1993 42 * The Regents of the University of California. All rights reserved. 43 * 44 * Redistribution and use in source and binary forms, with or without 45 * modification, are permitted provided that the following conditions 46 * are met: 47 * 1. Redistributions of source code must retain the above copyright 48 * notice, this list of conditions and the following disclaimer. 49 * 2. Redistributions in binary form must reproduce the above copyright 50 * notice, this list of conditions and the following disclaimer in the 51 * documentation and/or other materials provided with the distribution. 52 * 3. Neither the name of the University nor the names of its contributors 53 * may be used to endorse or promote products derived from this software 54 * without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 57 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 58 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 59 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 60 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 61 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 62 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 66 * SUCH DAMAGE. 67 * 68 * @(#)uipc_usrreq.c 8.9 (Berkeley) 5/14/95 69 */ 70 71 /* 72 * Copyright (c) 1997 Christopher G. Demetriou. All rights reserved. 73 * 74 * Redistribution and use in source and binary forms, with or without 75 * modification, are permitted provided that the following conditions 76 * are met: 77 * 1. Redistributions of source code must retain the above copyright 78 * notice, this list of conditions and the following disclaimer. 79 * 2. Redistributions in binary form must reproduce the above copyright 80 * notice, this list of conditions and the following disclaimer in the 81 * documentation and/or other materials provided with the distribution. 82 * 3. All advertising materials mentioning features or use of this software 83 * must display the following acknowledgement: 84 * This product includes software developed by the University of 85 * California, Berkeley and its contributors. 86 * 4. Neither the name of the University nor the names of its contributors 87 * may be used to endorse or promote products derived from this software 88 * without specific prior written permission. 89 * 90 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 91 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 92 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 93 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 94 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 95 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 96 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 97 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 98 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 99 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 100 * SUCH DAMAGE. 101 * 102 * @(#)uipc_usrreq.c 8.9 (Berkeley) 5/14/95 103 */ 104 105 #include <sys/cdefs.h> 106 __KERNEL_RCSID(0, "$NetBSD: uipc_usrreq.c,v 1.74.2.1 2005/07/18 04:03:05 riz Exp $"); 107 108 #include <sys/param.h> 109 #include <sys/systm.h> 110 #include <sys/proc.h> 111 #include <sys/filedesc.h> 112 #include <sys/domain.h> 113 #include <sys/protosw.h> 114 #include <sys/socket.h> 115 #include <sys/socketvar.h> 116 #include <sys/unpcb.h> 117 #include <sys/un.h> 118 #include <sys/namei.h> 119 #include <sys/vnode.h> 120 #include <sys/file.h> 121 #include <sys/stat.h> 122 #include <sys/mbuf.h> 123 124 /* 125 * Unix communications domain. 126 * 127 * TODO: 128 * SEQPACKET, RDM 129 * rethink name space problems 130 * need a proper out-of-band 131 */ 132 struct sockaddr_un sun_noname = { sizeof(sun_noname), AF_LOCAL }; 133 ino_t unp_ino; /* prototype for fake inode numbers */ 134 135 struct mbuf *unp_addsockcred(struct proc *, struct mbuf *); 136 137 int 138 unp_output(m, control, unp, p) 139 struct mbuf *m, *control; 140 struct unpcb *unp; 141 struct proc *p; 142 { 143 struct socket *so2; 144 struct sockaddr_un *sun; 145 146 so2 = unp->unp_conn->unp_socket; 147 if (unp->unp_addr) 148 sun = unp->unp_addr; 149 else 150 sun = &sun_noname; 151 if (unp->unp_conn->unp_flags & UNP_WANTCRED) 152 control = unp_addsockcred(p, control); 153 if (sbappendaddr(&so2->so_rcv, (struct sockaddr *)sun, m, 154 control) == 0) { 155 m_freem(control); 156 m_freem(m); 157 return (ENOBUFS); 158 } else { 159 sorwakeup(so2); 160 return (0); 161 } 162 } 163 164 void 165 unp_setsockaddr(unp, nam) 166 struct unpcb *unp; 167 struct mbuf *nam; 168 { 169 struct sockaddr_un *sun; 170 171 if (unp->unp_addr) 172 sun = unp->unp_addr; 173 else 174 sun = &sun_noname; 175 nam->m_len = sun->sun_len; 176 if (nam->m_len > MLEN) 177 MEXTMALLOC(nam, nam->m_len, M_WAITOK); 178 memcpy(mtod(nam, caddr_t), sun, (size_t)nam->m_len); 179 } 180 181 void 182 unp_setpeeraddr(unp, nam) 183 struct unpcb *unp; 184 struct mbuf *nam; 185 { 186 struct sockaddr_un *sun; 187 188 if (unp->unp_conn && unp->unp_conn->unp_addr) 189 sun = unp->unp_conn->unp_addr; 190 else 191 sun = &sun_noname; 192 nam->m_len = sun->sun_len; 193 if (nam->m_len > MLEN) 194 MEXTMALLOC(nam, nam->m_len, M_WAITOK); 195 memcpy(mtod(nam, caddr_t), sun, (size_t)nam->m_len); 196 } 197 198 /*ARGSUSED*/ 199 int 200 uipc_usrreq(so, req, m, nam, control, p) 201 struct socket *so; 202 int req; 203 struct mbuf *m, *nam, *control; 204 struct proc *p; 205 { 206 struct unpcb *unp = sotounpcb(so); 207 struct socket *so2; 208 int error = 0; 209 210 if (req == PRU_CONTROL) 211 return (EOPNOTSUPP); 212 213 #ifdef DIAGNOSTIC 214 if (req != PRU_SEND && req != PRU_SENDOOB && control) 215 panic("uipc_usrreq: unexpected control mbuf"); 216 #endif 217 if (unp == 0 && req != PRU_ATTACH) { 218 error = EINVAL; 219 goto release; 220 } 221 222 switch (req) { 223 224 case PRU_ATTACH: 225 if (unp != 0) { 226 error = EISCONN; 227 break; 228 } 229 error = unp_attach(so); 230 break; 231 232 case PRU_DETACH: 233 unp_detach(unp); 234 break; 235 236 case PRU_BIND: 237 error = unp_bind(unp, nam, p); 238 break; 239 240 case PRU_LISTEN: 241 if (unp->unp_vnode == 0) 242 error = EINVAL; 243 break; 244 245 case PRU_CONNECT: 246 error = unp_connect(so, nam, p); 247 break; 248 249 case PRU_CONNECT2: 250 error = unp_connect2(so, (struct socket *)nam, PRU_CONNECT2); 251 break; 252 253 case PRU_DISCONNECT: 254 unp_disconnect(unp); 255 break; 256 257 case PRU_ACCEPT: 258 unp_setpeeraddr(unp, nam); 259 /* 260 * Mark the initiating STREAM socket as connected *ONLY* 261 * after it's been accepted. This prevents a client from 262 * overrunning a server and receiving ECONNREFUSED. 263 */ 264 if (unp->unp_conn != NULL && 265 (unp->unp_conn->unp_socket->so_state & SS_ISCONNECTING)) 266 soisconnected(unp->unp_conn->unp_socket); 267 break; 268 269 case PRU_SHUTDOWN: 270 socantsendmore(so); 271 unp_shutdown(unp); 272 break; 273 274 case PRU_RCVD: 275 switch (so->so_type) { 276 277 case SOCK_DGRAM: 278 panic("uipc 1"); 279 /*NOTREACHED*/ 280 281 case SOCK_STREAM: 282 #define rcv (&so->so_rcv) 283 #define snd (&so2->so_snd) 284 if (unp->unp_conn == 0) 285 break; 286 so2 = unp->unp_conn->unp_socket; 287 /* 288 * Adjust backpressure on sender 289 * and wakeup any waiting to write. 290 */ 291 snd->sb_mbmax += unp->unp_mbcnt - rcv->sb_mbcnt; 292 unp->unp_mbcnt = rcv->sb_mbcnt; 293 snd->sb_hiwat += unp->unp_cc - rcv->sb_cc; 294 unp->unp_cc = rcv->sb_cc; 295 sowwakeup(so2); 296 #undef snd 297 #undef rcv 298 break; 299 300 default: 301 panic("uipc 2"); 302 } 303 break; 304 305 case PRU_SEND: 306 /* 307 * Note: unp_internalize() rejects any control message 308 * other than SCM_RIGHTS, and only allows one. This 309 * has the side-effect of preventing a caller from 310 * forging SCM_CREDS. 311 */ 312 if (control && (error = unp_internalize(control, p))) { 313 goto die; 314 } 315 switch (so->so_type) { 316 317 case SOCK_DGRAM: { 318 if (nam) { 319 if ((so->so_state & SS_ISCONNECTED) != 0) { 320 error = EISCONN; 321 goto die; 322 } 323 error = unp_connect(so, nam, p); 324 if (error) { 325 die: 326 m_freem(control); 327 m_freem(m); 328 break; 329 } 330 } else { 331 if ((so->so_state & SS_ISCONNECTED) == 0) { 332 error = ENOTCONN; 333 goto die; 334 } 335 } 336 error = unp_output(m, control, unp, p); 337 if (nam) 338 unp_disconnect(unp); 339 break; 340 } 341 342 case SOCK_STREAM: 343 #define rcv (&so2->so_rcv) 344 #define snd (&so->so_snd) 345 if (unp->unp_conn == 0) 346 panic("uipc 3"); 347 so2 = unp->unp_conn->unp_socket; 348 if (unp->unp_conn->unp_flags & UNP_WANTCRED) { 349 /* 350 * Credentials are passed only once on 351 * SOCK_STREAM. 352 */ 353 unp->unp_conn->unp_flags &= ~UNP_WANTCRED; 354 control = unp_addsockcred(p, control); 355 } 356 /* 357 * Send to paired receive port, and then reduce 358 * send buffer hiwater marks to maintain backpressure. 359 * Wake up readers. 360 */ 361 if (control) { 362 if (sbappendcontrol(rcv, m, control) == 0) 363 m_freem(control); 364 } else 365 sbappend(rcv, m); 366 snd->sb_mbmax -= 367 rcv->sb_mbcnt - unp->unp_conn->unp_mbcnt; 368 unp->unp_conn->unp_mbcnt = rcv->sb_mbcnt; 369 snd->sb_hiwat -= rcv->sb_cc - unp->unp_conn->unp_cc; 370 unp->unp_conn->unp_cc = rcv->sb_cc; 371 sorwakeup(so2); 372 #undef snd 373 #undef rcv 374 break; 375 376 default: 377 panic("uipc 4"); 378 } 379 break; 380 381 case PRU_ABORT: 382 unp_drop(unp, ECONNABORTED); 383 384 #ifdef DIAGNOSTIC 385 if (so->so_pcb == 0) 386 panic("uipc 5: drop killed pcb"); 387 #endif 388 unp_detach(unp); 389 break; 390 391 case PRU_SENSE: 392 ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat; 393 if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) { 394 so2 = unp->unp_conn->unp_socket; 395 ((struct stat *) m)->st_blksize += so2->so_rcv.sb_cc; 396 } 397 ((struct stat *) m)->st_dev = NODEV; 398 if (unp->unp_ino == 0) 399 unp->unp_ino = unp_ino++; 400 ((struct stat *) m)->st_atimespec = 401 ((struct stat *) m)->st_mtimespec = 402 ((struct stat *) m)->st_ctimespec = unp->unp_ctime; 403 ((struct stat *) m)->st_ino = unp->unp_ino; 404 return (0); 405 406 case PRU_RCVOOB: 407 error = EOPNOTSUPP; 408 break; 409 410 case PRU_SENDOOB: 411 m_freem(control); 412 m_freem(m); 413 error = EOPNOTSUPP; 414 break; 415 416 case PRU_SOCKADDR: 417 unp_setsockaddr(unp, nam); 418 break; 419 420 case PRU_PEERADDR: 421 unp_setpeeraddr(unp, nam); 422 break; 423 424 default: 425 panic("piusrreq"); 426 } 427 428 release: 429 return (error); 430 } 431 432 /* 433 * Unix domain socket option processing. 434 */ 435 int 436 uipc_ctloutput(op, so, level, optname, mp) 437 int op; 438 struct socket *so; 439 int level, optname; 440 struct mbuf **mp; 441 { 442 struct unpcb *unp = sotounpcb(so); 443 struct mbuf *m = *mp; 444 int optval = 0, error = 0; 445 446 if (level != 0) { 447 error = EINVAL; 448 if (op == PRCO_SETOPT && m) 449 (void) m_free(m); 450 } else switch (op) { 451 452 case PRCO_SETOPT: 453 switch (optname) { 454 case LOCAL_CREDS: 455 case LOCAL_CONNWAIT: 456 if (m == NULL || m->m_len != sizeof(int)) 457 error = EINVAL; 458 else { 459 optval = *mtod(m, int *); 460 switch (optname) { 461 #define OPTSET(bit) \ 462 if (optval) \ 463 unp->unp_flags |= (bit); \ 464 else \ 465 unp->unp_flags &= ~(bit); 466 467 case LOCAL_CREDS: 468 OPTSET(UNP_WANTCRED); 469 break; 470 case LOCAL_CONNWAIT: 471 OPTSET(UNP_CONNWAIT); 472 break; 473 } 474 } 475 break; 476 #undef OPTSET 477 478 default: 479 error = ENOPROTOOPT; 480 break; 481 } 482 if (m) 483 (void) m_free(m); 484 break; 485 486 case PRCO_GETOPT: 487 switch (optname) { 488 case LOCAL_CREDS: 489 *mp = m = m_get(M_WAIT, MT_SOOPTS); 490 m->m_len = sizeof(int); 491 switch (optname) { 492 493 #define OPTBIT(bit) (unp->unp_flags & (bit) ? 1 : 0) 494 495 case LOCAL_CREDS: 496 optval = OPTBIT(UNP_WANTCRED); 497 break; 498 } 499 *mtod(m, int *) = optval; 500 break; 501 #undef OPTBIT 502 503 default: 504 error = ENOPROTOOPT; 505 break; 506 } 507 break; 508 } 509 return (error); 510 } 511 512 /* 513 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 514 * for stream sockets, although the total for sender and receiver is 515 * actually only PIPSIZ. 516 * Datagram sockets really use the sendspace as the maximum datagram size, 517 * and don't really want to reserve the sendspace. Their recvspace should 518 * be large enough for at least one max-size datagram plus address. 519 */ 520 #define PIPSIZ 4096 521 u_long unpst_sendspace = PIPSIZ; 522 u_long unpst_recvspace = PIPSIZ; 523 u_long unpdg_sendspace = 2*1024; /* really max datagram size */ 524 u_long unpdg_recvspace = 4*1024; 525 526 int unp_rights; /* file descriptors in flight */ 527 528 int 529 unp_attach(so) 530 struct socket *so; 531 { 532 struct unpcb *unp; 533 struct timeval tv; 534 int error; 535 536 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 537 switch (so->so_type) { 538 539 case SOCK_STREAM: 540 error = soreserve(so, unpst_sendspace, unpst_recvspace); 541 break; 542 543 case SOCK_DGRAM: 544 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 545 break; 546 547 default: 548 panic("unp_attach"); 549 } 550 if (error) 551 return (error); 552 } 553 unp = malloc(sizeof(*unp), M_PCB, M_NOWAIT); 554 if (unp == NULL) 555 return (ENOBUFS); 556 memset((caddr_t)unp, 0, sizeof(*unp)); 557 unp->unp_socket = so; 558 so->so_pcb = unp; 559 microtime(&tv); 560 TIMEVAL_TO_TIMESPEC(&tv, &unp->unp_ctime); 561 return (0); 562 } 563 564 void 565 unp_detach(unp) 566 struct unpcb *unp; 567 { 568 569 if (unp->unp_vnode) { 570 unp->unp_vnode->v_socket = 0; 571 vrele(unp->unp_vnode); 572 unp->unp_vnode = 0; 573 } 574 if (unp->unp_conn) 575 unp_disconnect(unp); 576 while (unp->unp_refs) 577 unp_drop(unp->unp_refs, ECONNRESET); 578 soisdisconnected(unp->unp_socket); 579 unp->unp_socket->so_pcb = 0; 580 if (unp->unp_addr) 581 free(unp->unp_addr, M_SONAME); 582 if (unp_rights) { 583 /* 584 * Normally the receive buffer is flushed later, 585 * in sofree, but if our receive buffer holds references 586 * to descriptors that are now garbage, we will dispose 587 * of those descriptor references after the garbage collector 588 * gets them (resulting in a "panic: closef: count < 0"). 589 */ 590 sorflush(unp->unp_socket); 591 free(unp, M_PCB); 592 unp_gc(); 593 } else 594 free(unp, M_PCB); 595 } 596 597 int 598 unp_bind(unp, nam, p) 599 struct unpcb *unp; 600 struct mbuf *nam; 601 struct proc *p; 602 { 603 struct sockaddr_un *sun; 604 struct vnode *vp; 605 struct mount *mp; 606 struct vattr vattr; 607 size_t addrlen; 608 int error; 609 struct nameidata nd; 610 611 if (unp->unp_vnode != 0) 612 return (EINVAL); 613 614 /* 615 * Allocate the new sockaddr. We have to allocate one 616 * extra byte so that we can ensure that the pathname 617 * is nul-terminated. 618 */ 619 addrlen = nam->m_len + 1; 620 sun = malloc(addrlen, M_SONAME, M_WAITOK); 621 m_copydata(nam, 0, nam->m_len, (caddr_t)sun); 622 *(((char *)sun) + nam->m_len) = '\0'; 623 624 restart: 625 NDINIT(&nd, CREATE, FOLLOW | LOCKPARENT, UIO_SYSSPACE, 626 sun->sun_path, p); 627 628 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 629 if ((error = namei(&nd)) != 0) 630 goto bad; 631 vp = nd.ni_vp; 632 if (vp != NULL || vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) { 633 VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd); 634 if (nd.ni_dvp == vp) 635 vrele(nd.ni_dvp); 636 else 637 vput(nd.ni_dvp); 638 vrele(vp); 639 if (vp != NULL) { 640 error = EADDRINUSE; 641 goto bad; 642 } 643 error = vn_start_write(NULL, &mp, 644 V_WAIT | V_SLEEPONLY | V_PCATCH); 645 if (error) 646 goto bad; 647 goto restart; 648 } 649 VATTR_NULL(&vattr); 650 vattr.va_type = VSOCK; 651 vattr.va_mode = ACCESSPERMS; 652 VOP_LEASE(nd.ni_dvp, p, p->p_ucred, LEASE_WRITE); 653 error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr); 654 vn_finished_write(mp, 0); 655 if (error) 656 goto bad; 657 vp = nd.ni_vp; 658 vp->v_socket = unp->unp_socket; 659 unp->unp_vnode = vp; 660 unp->unp_addrlen = addrlen; 661 unp->unp_addr = sun; 662 VOP_UNLOCK(vp, 0); 663 return (0); 664 665 bad: 666 free(sun, M_SONAME); 667 return (error); 668 } 669 670 int 671 unp_connect(so, nam, p) 672 struct socket *so; 673 struct mbuf *nam; 674 struct proc *p; 675 { 676 struct sockaddr_un *sun; 677 struct vnode *vp; 678 struct socket *so2, *so3; 679 struct unpcb *unp2, *unp3; 680 size_t addrlen; 681 int error; 682 struct nameidata nd; 683 684 /* 685 * Allocate a temporary sockaddr. We have to allocate one extra 686 * byte so that we can ensure that the pathname is nul-terminated. 687 * When we establish the connection, we copy the other PCB's 688 * sockaddr to our own. 689 */ 690 addrlen = nam->m_len + 1; 691 sun = malloc(addrlen, M_SONAME, M_WAITOK); 692 m_copydata(nam, 0, nam->m_len, (caddr_t)sun); 693 *(((char *)sun) + nam->m_len) = '\0'; 694 695 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, sun->sun_path, p); 696 697 if ((error = namei(&nd)) != 0) 698 goto bad2; 699 vp = nd.ni_vp; 700 if (vp->v_type != VSOCK) { 701 error = ENOTSOCK; 702 goto bad; 703 } 704 if ((error = VOP_ACCESS(vp, VWRITE, p->p_ucred, p)) != 0) 705 goto bad; 706 so2 = vp->v_socket; 707 if (so2 == 0) { 708 error = ECONNREFUSED; 709 goto bad; 710 } 711 if (so->so_type != so2->so_type) { 712 error = EPROTOTYPE; 713 goto bad; 714 } 715 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 716 if ((so2->so_options & SO_ACCEPTCONN) == 0 || 717 (so3 = sonewconn(so2, 0)) == 0) { 718 error = ECONNREFUSED; 719 goto bad; 720 } 721 unp2 = sotounpcb(so2); 722 unp3 = sotounpcb(so3); 723 if (unp2->unp_addr) { 724 unp3->unp_addr = malloc(unp2->unp_addrlen, 725 M_SONAME, M_WAITOK); 726 memcpy(unp3->unp_addr, unp2->unp_addr, 727 unp2->unp_addrlen); 728 unp3->unp_addrlen = unp2->unp_addrlen; 729 } 730 unp3->unp_flags = unp2->unp_flags; 731 so2 = so3; 732 } 733 error = unp_connect2(so, so2, PRU_CONNECT); 734 bad: 735 vput(vp); 736 bad2: 737 free(sun, M_SONAME); 738 return (error); 739 } 740 741 int 742 unp_connect2(so, so2, req) 743 struct socket *so; 744 struct socket *so2; 745 int req; 746 { 747 struct unpcb *unp = sotounpcb(so); 748 struct unpcb *unp2; 749 750 if (so2->so_type != so->so_type) 751 return (EPROTOTYPE); 752 unp2 = sotounpcb(so2); 753 unp->unp_conn = unp2; 754 switch (so->so_type) { 755 756 case SOCK_DGRAM: 757 unp->unp_nextref = unp2->unp_refs; 758 unp2->unp_refs = unp; 759 soisconnected(so); 760 break; 761 762 case SOCK_STREAM: 763 unp2->unp_conn = unp; 764 if (req == PRU_CONNECT && 765 ((unp->unp_flags | unp2->unp_flags) & UNP_CONNWAIT)) 766 soisconnecting(so); 767 else 768 soisconnected(so); 769 soisconnected(so2); 770 break; 771 772 default: 773 panic("unp_connect2"); 774 } 775 return (0); 776 } 777 778 void 779 unp_disconnect(unp) 780 struct unpcb *unp; 781 { 782 struct unpcb *unp2 = unp->unp_conn; 783 784 if (unp2 == 0) 785 return; 786 unp->unp_conn = 0; 787 switch (unp->unp_socket->so_type) { 788 789 case SOCK_DGRAM: 790 if (unp2->unp_refs == unp) 791 unp2->unp_refs = unp->unp_nextref; 792 else { 793 unp2 = unp2->unp_refs; 794 for (;;) { 795 if (unp2 == 0) 796 panic("unp_disconnect"); 797 if (unp2->unp_nextref == unp) 798 break; 799 unp2 = unp2->unp_nextref; 800 } 801 unp2->unp_nextref = unp->unp_nextref; 802 } 803 unp->unp_nextref = 0; 804 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 805 break; 806 807 case SOCK_STREAM: 808 soisdisconnected(unp->unp_socket); 809 unp2->unp_conn = 0; 810 soisdisconnected(unp2->unp_socket); 811 break; 812 } 813 } 814 815 #ifdef notdef 816 unp_abort(unp) 817 struct unpcb *unp; 818 { 819 820 unp_detach(unp); 821 } 822 #endif 823 824 void 825 unp_shutdown(unp) 826 struct unpcb *unp; 827 { 828 struct socket *so; 829 830 if (unp->unp_socket->so_type == SOCK_STREAM && unp->unp_conn && 831 (so = unp->unp_conn->unp_socket)) 832 socantrcvmore(so); 833 } 834 835 void 836 unp_drop(unp, errno) 837 struct unpcb *unp; 838 int errno; 839 { 840 struct socket *so = unp->unp_socket; 841 842 so->so_error = errno; 843 unp_disconnect(unp); 844 if (so->so_head) { 845 so->so_pcb = 0; 846 sofree(so); 847 if (unp->unp_addr) 848 free(unp->unp_addr, M_SONAME); 849 free(unp, M_PCB); 850 } 851 } 852 853 #ifdef notdef 854 unp_drain() 855 { 856 857 } 858 #endif 859 860 int 861 unp_externalize(rights) 862 struct mbuf *rights; 863 { 864 struct proc *p = curproc; /* XXX */ 865 struct cmsghdr *cm = mtod(rights, struct cmsghdr *); 866 int i, *fdp; 867 struct file **rp; 868 struct file *fp; 869 int nfds, error = 0; 870 871 nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) / 872 sizeof(struct file *); 873 rp = (struct file **)CMSG_DATA(cm); 874 875 fdp = malloc(nfds * sizeof(int), M_TEMP, M_WAITOK); 876 877 /* Make sure the recipient should be able to see the descriptors.. */ 878 if (p->p_cwdi->cwdi_rdir != NULL) { 879 rp = (struct file **)CMSG_DATA(cm); 880 for (i = 0; i < nfds; i++) { 881 fp = *rp++; 882 /* 883 * If we are in a chroot'ed directory, and 884 * someone wants to pass us a directory, make 885 * sure it's inside the subtree we're allowed 886 * to access. 887 */ 888 if (fp->f_type == DTYPE_VNODE) { 889 struct vnode *vp = (struct vnode *)fp->f_data; 890 if ((vp->v_type == VDIR) && 891 !vn_isunder(vp, p->p_cwdi->cwdi_rdir, p)) { 892 error = EPERM; 893 break; 894 } 895 } 896 } 897 } 898 899 restart: 900 rp = (struct file **)CMSG_DATA(cm); 901 if (error != 0) { 902 for (i = 0; i < nfds; i++) { 903 fp = *rp; 904 /* 905 * zero the pointer before calling unp_discard, 906 * since it may end up in unp_gc().. 907 */ 908 *rp++ = 0; 909 unp_discard(fp); 910 } 911 goto out; 912 } 913 914 /* 915 * First loop -- allocate file descriptor table slots for the 916 * new descriptors. 917 */ 918 for (i = 0; i < nfds; i++) { 919 fp = *rp++; 920 if ((error = fdalloc(p, 0, &fdp[i])) != 0) { 921 /* 922 * Back out what we've done so far. 923 */ 924 for (--i; i >= 0; i--) 925 fdremove(p->p_fd, fdp[i]); 926 927 if (error == ENOSPC) { 928 fdexpand(p); 929 error = 0; 930 } else { 931 /* 932 * This is the error that has historically 933 * been returned, and some callers may 934 * expect it. 935 */ 936 error = EMSGSIZE; 937 } 938 goto restart; 939 } 940 941 /* 942 * Make the slot reference the descriptor so that 943 * fdalloc() works properly.. We finalize it all 944 * in the loop below. 945 */ 946 p->p_fd->fd_ofiles[fdp[i]] = fp; 947 } 948 949 /* 950 * Now that adding them has succeeded, update all of the 951 * descriptor passing state. 952 */ 953 rp = (struct file **)CMSG_DATA(cm); 954 for (i = 0; i < nfds; i++) { 955 fp = *rp++; 956 fp->f_msgcount--; 957 unp_rights--; 958 } 959 960 /* 961 * Copy temporary array to message and adjust length, in case of 962 * transition from large struct file pointers to ints. 963 */ 964 memcpy(CMSG_DATA(cm), fdp, nfds * sizeof(int)); 965 cm->cmsg_len = CMSG_LEN(nfds * sizeof(int)); 966 rights->m_len = CMSG_SPACE(nfds * sizeof(int)); 967 out: 968 free(fdp, M_TEMP); 969 return (error); 970 } 971 972 int 973 unp_internalize(control, p) 974 struct mbuf *control; 975 struct proc *p; 976 { 977 struct filedesc *fdescp = p->p_fd; 978 struct cmsghdr *newcm, *cm = mtod(control, struct cmsghdr *); 979 struct file **rp, **files; 980 struct file *fp; 981 int i, fd, *fdp; 982 int nfds; 983 u_int neededspace; 984 985 /* Sanity check the control message header */ 986 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET || 987 cm->cmsg_len != control->m_len) 988 return (EINVAL); 989 990 /* Verify that the file descriptors are valid */ 991 nfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) / sizeof(int); 992 fdp = (int *)CMSG_DATA(cm); 993 for (i = 0; i < nfds; i++) { 994 fd = *fdp++; 995 if ((fp = fd_getfile(fdescp, fd)) == NULL) 996 return (EBADF); 997 simple_unlock(&fp->f_slock); 998 } 999 1000 /* Make sure we have room for the struct file pointers */ 1001 neededspace = CMSG_SPACE(nfds * sizeof(struct file *)) - 1002 control->m_len; 1003 if (neededspace > M_TRAILINGSPACE(control)) { 1004 1005 /* allocate new space and copy header into it */ 1006 newcm = malloc( 1007 CMSG_SPACE(nfds * sizeof(struct file *)), 1008 M_MBUF, M_WAITOK); 1009 if (newcm == NULL) 1010 return (E2BIG); 1011 memcpy(newcm, cm, sizeof(struct cmsghdr)); 1012 files = (struct file **)CMSG_DATA(newcm); 1013 } else { 1014 /* we can convert in-place */ 1015 newcm = NULL; 1016 files = (struct file **)CMSG_DATA(cm); 1017 } 1018 1019 /* 1020 * Transform the file descriptors into struct file pointers, in 1021 * reverse order so that if pointers are bigger than ints, the 1022 * int won't get until we're done. 1023 */ 1024 fdp = (int *)CMSG_DATA(cm) + nfds - 1; 1025 rp = files + nfds - 1; 1026 for (i = 0; i < nfds; i++) { 1027 fp = fdescp->fd_ofiles[*fdp--]; 1028 simple_lock(&fp->f_slock); 1029 #ifdef DIAGNOSTIC 1030 if (fp->f_iflags & FIF_WANTCLOSE) 1031 panic("unp_internalize: file already closed"); 1032 #endif 1033 *rp-- = fp; 1034 fp->f_count++; 1035 fp->f_msgcount++; 1036 simple_unlock(&fp->f_slock); 1037 unp_rights++; 1038 } 1039 1040 if (newcm) { 1041 if (control->m_flags & M_EXT) 1042 MEXTREMOVE(control); 1043 MEXTADD(control, newcm, 1044 CMSG_SPACE(nfds * sizeof(struct file *)), 1045 M_MBUF, NULL, NULL); 1046 cm = newcm; 1047 } 1048 1049 /* adjust message & mbuf to note amount of space actually used. */ 1050 cm->cmsg_len = CMSG_LEN(nfds * sizeof(struct file *)); 1051 control->m_len = CMSG_SPACE(nfds * sizeof(struct file *)); 1052 1053 return (0); 1054 } 1055 1056 struct mbuf * 1057 unp_addsockcred(p, control) 1058 struct proc *p; 1059 struct mbuf *control; 1060 { 1061 struct cmsghdr *cmp; 1062 struct sockcred *sc; 1063 struct mbuf *m, *n; 1064 int len, space, i; 1065 1066 len = CMSG_LEN(SOCKCREDSIZE(p->p_ucred->cr_ngroups)); 1067 space = CMSG_SPACE(SOCKCREDSIZE(p->p_ucred->cr_ngroups)); 1068 1069 m = m_get(M_WAIT, MT_CONTROL); 1070 if (space > MLEN) { 1071 if (space > MCLBYTES) 1072 MEXTMALLOC(m, space, M_WAITOK); 1073 else 1074 m_clget(m, M_WAIT); 1075 if ((m->m_flags & M_EXT) == 0) { 1076 m_free(m); 1077 return (control); 1078 } 1079 } 1080 1081 m->m_len = space; 1082 m->m_next = NULL; 1083 cmp = mtod(m, struct cmsghdr *); 1084 sc = (struct sockcred *)CMSG_DATA(cmp); 1085 cmp->cmsg_len = len; 1086 cmp->cmsg_level = SOL_SOCKET; 1087 cmp->cmsg_type = SCM_CREDS; 1088 sc->sc_uid = p->p_cred->p_ruid; 1089 sc->sc_euid = p->p_ucred->cr_uid; 1090 sc->sc_gid = p->p_cred->p_rgid; 1091 sc->sc_egid = p->p_ucred->cr_gid; 1092 sc->sc_ngroups = p->p_ucred->cr_ngroups; 1093 for (i = 0; i < sc->sc_ngroups; i++) 1094 sc->sc_groups[i] = p->p_ucred->cr_groups[i]; 1095 1096 /* 1097 * If a control message already exists, append us to the end. 1098 */ 1099 if (control != NULL) { 1100 for (n = control; n->m_next != NULL; n = n->m_next) 1101 ; 1102 n->m_next = m; 1103 } else 1104 control = m; 1105 1106 return (control); 1107 } 1108 1109 int unp_defer, unp_gcing; 1110 extern struct domain unixdomain; 1111 1112 /* 1113 * Comment added long after the fact explaining what's going on here. 1114 * Do a mark-sweep GC of file descriptors on the system, to free up 1115 * any which are caught in flight to an about-to-be-closed socket. 1116 * 1117 * Traditional mark-sweep gc's start at the "root", and mark 1118 * everything reachable from the root (which, in our case would be the 1119 * process table). The mark bits are cleared during the sweep. 1120 * 1121 * XXX For some inexplicable reason (perhaps because the file 1122 * descriptor tables used to live in the u area which could be swapped 1123 * out and thus hard to reach), we do multiple scans over the set of 1124 * descriptors, using use *two* mark bits per object (DEFER and MARK). 1125 * Whenever we find a descriptor which references other descriptors, 1126 * the ones it references are marked with both bits, and we iterate 1127 * over the whole file table until there are no more DEFER bits set. 1128 * We also make an extra pass *before* the GC to clear the mark bits, 1129 * which could have been cleared at almost no cost during the previous 1130 * sweep. 1131 * 1132 * XXX MP: this needs to run with locks such that no other thread of 1133 * control can create or destroy references to file descriptors. it 1134 * may be necessary to defer the GC until later (when the locking 1135 * situation is more hospitable); it may be necessary to push this 1136 * into a separate thread. 1137 */ 1138 void 1139 unp_gc() 1140 { 1141 struct file *fp, *nextfp; 1142 struct socket *so, *so1; 1143 struct file **extra_ref, **fpp; 1144 int nunref, i; 1145 1146 if (unp_gcing) 1147 return; 1148 unp_gcing = 1; 1149 unp_defer = 0; 1150 1151 /* Clear mark bits */ 1152 LIST_FOREACH(fp, &filehead, f_list) 1153 fp->f_flag &= ~(FMARK|FDEFER); 1154 1155 /* 1156 * Iterate over the set of descriptors, marking ones believed 1157 * (based on refcount) to be referenced from a process, and 1158 * marking for rescan descriptors which are queued on a socket. 1159 */ 1160 do { 1161 LIST_FOREACH(fp, &filehead, f_list) { 1162 if (fp->f_flag & FDEFER) { 1163 fp->f_flag &= ~FDEFER; 1164 unp_defer--; 1165 #ifdef DIAGNOSTIC 1166 if (fp->f_count == 0) 1167 panic("unp_gc: deferred unreferenced socket"); 1168 #endif 1169 } else { 1170 if (fp->f_count == 0) 1171 continue; 1172 if (fp->f_flag & FMARK) 1173 continue; 1174 if (fp->f_count == fp->f_msgcount) 1175 continue; 1176 } 1177 fp->f_flag |= FMARK; 1178 1179 if (fp->f_type != DTYPE_SOCKET || 1180 (so = (struct socket *)fp->f_data) == 0) 1181 continue; 1182 if (so->so_proto->pr_domain != &unixdomain || 1183 (so->so_proto->pr_flags&PR_RIGHTS) == 0) 1184 continue; 1185 #ifdef notdef 1186 if (so->so_rcv.sb_flags & SB_LOCK) { 1187 /* 1188 * This is problematical; it's not clear 1189 * we need to wait for the sockbuf to be 1190 * unlocked (on a uniprocessor, at least), 1191 * and it's also not clear what to do 1192 * if sbwait returns an error due to receipt 1193 * of a signal. If sbwait does return 1194 * an error, we'll go into an infinite 1195 * loop. Delete all of this for now. 1196 */ 1197 (void) sbwait(&so->so_rcv); 1198 goto restart; 1199 } 1200 #endif 1201 unp_scan(so->so_rcv.sb_mb, unp_mark, 0); 1202 /* 1203 * mark descriptors referenced from sockets queued on the accept queue as well. 1204 */ 1205 if (so->so_options & SO_ACCEPTCONN) { 1206 TAILQ_FOREACH(so1, &so->so_q0, so_qe) { 1207 unp_scan(so1->so_rcv.sb_mb, unp_mark, 0); 1208 } 1209 TAILQ_FOREACH(so1, &so->so_q, so_qe) { 1210 unp_scan(so1->so_rcv.sb_mb, unp_mark, 0); 1211 } 1212 } 1213 1214 } 1215 } while (unp_defer); 1216 /* 1217 * Sweep pass. Find unmarked descriptors, and free them. 1218 * 1219 * We grab an extra reference to each of the file table entries 1220 * that are not otherwise accessible and then free the rights 1221 * that are stored in messages on them. 1222 * 1223 * The bug in the original code is a little tricky, so I'll describe 1224 * what's wrong with it here. 1225 * 1226 * It is incorrect to simply unp_discard each entry for f_msgcount 1227 * times -- consider the case of sockets A and B that contain 1228 * references to each other. On a last close of some other socket, 1229 * we trigger a gc since the number of outstanding rights (unp_rights) 1230 * is non-zero. If during the sweep phase the gc code un_discards, 1231 * we end up doing a (full) closef on the descriptor. A closef on A 1232 * results in the following chain. Closef calls soo_close, which 1233 * calls soclose. Soclose calls first (through the switch 1234 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply 1235 * returns because the previous instance had set unp_gcing, and 1236 * we return all the way back to soclose, which marks the socket 1237 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush 1238 * to free up the rights that are queued in messages on the socket A, 1239 * i.e., the reference on B. The sorflush calls via the dom_dispose 1240 * switch unp_dispose, which unp_scans with unp_discard. This second 1241 * instance of unp_discard just calls closef on B. 1242 * 1243 * Well, a similar chain occurs on B, resulting in a sorflush on B, 1244 * which results in another closef on A. Unfortunately, A is already 1245 * being closed, and the descriptor has already been marked with 1246 * SS_NOFDREF, and soclose panics at this point. 1247 * 1248 * Here, we first take an extra reference to each inaccessible 1249 * descriptor. Then, if the inaccessible descriptor is a 1250 * socket, we call sorflush in case it is a Unix domain 1251 * socket. After we destroy all the rights carried in 1252 * messages, we do a last closef to get rid of our extra 1253 * reference. This is the last close, and the unp_detach etc 1254 * will shut down the socket. 1255 * 1256 * 91/09/19, bsy@cs.cmu.edu 1257 */ 1258 extra_ref = malloc(nfiles * sizeof(struct file *), M_FILE, M_WAITOK); 1259 for (nunref = 0, fp = LIST_FIRST(&filehead), fpp = extra_ref; fp != 0; 1260 fp = nextfp) { 1261 nextfp = LIST_NEXT(fp, f_list); 1262 simple_lock(&fp->f_slock); 1263 if (fp->f_count != 0 && 1264 fp->f_count == fp->f_msgcount && !(fp->f_flag & FMARK)) { 1265 *fpp++ = fp; 1266 nunref++; 1267 fp->f_count++; 1268 } 1269 simple_unlock(&fp->f_slock); 1270 } 1271 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp) { 1272 fp = *fpp; 1273 simple_lock(&fp->f_slock); 1274 FILE_USE(fp); 1275 if (fp->f_type == DTYPE_SOCKET) 1276 sorflush((struct socket *)fp->f_data); 1277 FILE_UNUSE(fp, NULL); 1278 } 1279 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp) { 1280 fp = *fpp; 1281 simple_lock(&fp->f_slock); 1282 FILE_USE(fp); 1283 (void) closef(fp, (struct proc *)0); 1284 } 1285 free((caddr_t)extra_ref, M_FILE); 1286 unp_gcing = 0; 1287 } 1288 1289 void 1290 unp_dispose(m) 1291 struct mbuf *m; 1292 { 1293 1294 if (m) 1295 unp_scan(m, unp_discard, 1); 1296 } 1297 1298 void 1299 unp_scan(m0, op, discard) 1300 struct mbuf *m0; 1301 void (*op)(struct file *); 1302 int discard; 1303 { 1304 struct mbuf *m; 1305 struct file **rp; 1306 struct cmsghdr *cm; 1307 int i; 1308 int qfds; 1309 1310 while (m0) { 1311 for (m = m0; m; m = m->m_next) { 1312 if (m->m_type == MT_CONTROL && 1313 m->m_len >= sizeof(*cm)) { 1314 cm = mtod(m, struct cmsghdr *); 1315 if (cm->cmsg_level != SOL_SOCKET || 1316 cm->cmsg_type != SCM_RIGHTS) 1317 continue; 1318 qfds = (cm->cmsg_len - CMSG_ALIGN(sizeof(*cm))) 1319 / sizeof(struct file *); 1320 rp = (struct file **)CMSG_DATA(cm); 1321 for (i = 0; i < qfds; i++) { 1322 struct file *fp = *rp; 1323 if (discard) 1324 *rp = 0; 1325 (*op)(fp); 1326 rp++; 1327 } 1328 break; /* XXX, but saves time */ 1329 } 1330 } 1331 m0 = m0->m_nextpkt; 1332 } 1333 } 1334 1335 void 1336 unp_mark(fp) 1337 struct file *fp; 1338 { 1339 if (fp == NULL) 1340 return; 1341 1342 if (fp->f_flag & FMARK) 1343 return; 1344 1345 /* If we're already deferred, don't screw up the defer count */ 1346 if (fp->f_flag & FDEFER) 1347 return; 1348 1349 /* 1350 * Minimize the number of deferrals... Sockets are the only 1351 * type of descriptor which can hold references to another 1352 * descriptor, so just mark other descriptors, and defer 1353 * unmarked sockets for the next pass. 1354 */ 1355 if (fp->f_type == DTYPE_SOCKET) { 1356 unp_defer++; 1357 if (fp->f_count == 0) 1358 panic("unp_mark: queued unref"); 1359 fp->f_flag |= FDEFER; 1360 } else { 1361 fp->f_flag |= FMARK; 1362 } 1363 return; 1364 } 1365 1366 void 1367 unp_discard(fp) 1368 struct file *fp; 1369 { 1370 if (fp == NULL) 1371 return; 1372 simple_lock(&fp->f_slock); 1373 fp->f_usecount++; /* i.e. FILE_USE(fp) sans locking */ 1374 fp->f_msgcount--; 1375 simple_unlock(&fp->f_slock); 1376 unp_rights--; 1377 (void) closef(fp, (struct proc *)0); 1378 }
Cache object: 7f3e5e2c150687159a98c35a6ae02d72
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