1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 * 17 * @(#)uipc_usrreq.c 7.8 (Berkeley) 08/22/88 18 */ 19 20 #include "param.h" 21 #include "dir.h" 22 #include "user.h" 23 #include "mbuf.h" 24 #include "domain.h" 25 #include "protosw.h" 26 #include "socket.h" 27 #include "socketvar.h" 28 #include "unpcb.h" 29 #include "un.h" 30 #include "inode.h" 31 #include "file.h" 32 #include "stat.h" 33 34 /* 35 * Unix communications domain. 36 * 37 * TODO: 38 * SEQPACKET, RDM 39 * rethink name space problems 40 * need a proper out-of-band 41 */ 42 struct sockaddr sun_noname = { AF_UNIX }; 43 ino_t unp_ino; /* prototype for fake inode numbers */ 44 45 /*ARGSUSED*/ 46 uipc_usrreq(so, req, m, nam, rights) 47 struct socket *so; 48 int req; 49 struct mbuf *m, *nam, *rights; 50 { 51 struct unpcb *unp = sotounpcb(so); 52 register struct socket *so2; 53 int error = 0; 54 55 if (req == PRU_CONTROL) 56 return (EOPNOTSUPP); 57 if (req != PRU_SEND && rights && rights->m_len) { 58 error = EOPNOTSUPP; 59 goto release; 60 } 61 if (unp == 0 && req != PRU_ATTACH) { 62 error = EINVAL; 63 goto release; 64 } 65 switch (req) { 66 67 case PRU_ATTACH: 68 if (unp) { 69 error = EISCONN; 70 break; 71 } 72 error = unp_attach(so); 73 break; 74 75 case PRU_DETACH: 76 unp_detach(unp); 77 break; 78 79 case PRU_BIND: 80 error = unp_bind(unp, nam); 81 break; 82 83 case PRU_LISTEN: 84 if (unp->unp_inode == 0) 85 error = EINVAL; 86 break; 87 88 case PRU_CONNECT: 89 error = unp_connect(so, nam); 90 break; 91 92 case PRU_CONNECT2: 93 error = unp_connect2(so, (struct socket *)nam); 94 break; 95 96 case PRU_DISCONNECT: 97 unp_disconnect(unp); 98 break; 99 100 case PRU_ACCEPT: 101 /* 102 * Pass back name of connected socket, 103 * if it was bound and we are still connected 104 * (our peer may have closed already!). 105 */ 106 if (unp->unp_conn && unp->unp_conn->unp_addr) { 107 nam->m_len = unp->unp_conn->unp_addr->m_len; 108 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 109 mtod(nam, caddr_t), (unsigned)nam->m_len); 110 } else { 111 nam->m_len = sizeof(sun_noname); 112 *(mtod(nam, struct sockaddr *)) = sun_noname; 113 } 114 break; 115 116 case PRU_SHUTDOWN: 117 socantsendmore(so); 118 unp_usrclosed(unp); 119 break; 120 121 case PRU_RCVD: 122 switch (so->so_type) { 123 124 case SOCK_DGRAM: 125 panic("uipc 1"); 126 /*NOTREACHED*/ 127 128 case SOCK_STREAM: 129 #define rcv (&so->so_rcv) 130 #define snd (&so2->so_snd) 131 if (unp->unp_conn == 0) 132 break; 133 so2 = unp->unp_conn->unp_socket; 134 /* 135 * Adjust backpressure on sender 136 * and wakeup any waiting to write. 137 */ 138 snd->sb_mbmax += unp->unp_mbcnt - rcv->sb_mbcnt; 139 unp->unp_mbcnt = rcv->sb_mbcnt; 140 snd->sb_hiwat += unp->unp_cc - rcv->sb_cc; 141 unp->unp_cc = rcv->sb_cc; 142 sowwakeup(so2); 143 #undef snd 144 #undef rcv 145 break; 146 147 default: 148 panic("uipc 2"); 149 } 150 break; 151 152 case PRU_SEND: 153 if (rights) { 154 error = unp_internalize(rights); 155 if (error) 156 break; 157 } 158 switch (so->so_type) { 159 160 case SOCK_DGRAM: { 161 struct sockaddr *from; 162 163 if (nam) { 164 if (unp->unp_conn) { 165 error = EISCONN; 166 break; 167 } 168 error = unp_connect(so, nam); 169 if (error) 170 break; 171 } else { 172 if (unp->unp_conn == 0) { 173 error = ENOTCONN; 174 break; 175 } 176 } 177 so2 = unp->unp_conn->unp_socket; 178 if (unp->unp_addr) 179 from = mtod(unp->unp_addr, struct sockaddr *); 180 else 181 from = &sun_noname; 182 if (sbspace(&so2->so_rcv) > 0 && 183 sbappendaddr(&so2->so_rcv, from, m, rights)) { 184 sorwakeup(so2); 185 m = 0; 186 } else 187 error = ENOBUFS; 188 if (nam) 189 unp_disconnect(unp); 190 break; 191 } 192 193 case SOCK_STREAM: 194 #define rcv (&so2->so_rcv) 195 #define snd (&so->so_snd) 196 if (so->so_state & SS_CANTSENDMORE) { 197 error = EPIPE; 198 break; 199 } 200 if (unp->unp_conn == 0) 201 panic("uipc 3"); 202 so2 = unp->unp_conn->unp_socket; 203 /* 204 * Send to paired receive port, and then reduce 205 * send buffer hiwater marks to maintain backpressure. 206 * Wake up readers. 207 */ 208 if (rights) 209 (void)sbappendrights(rcv, m, rights); 210 else 211 sbappend(rcv, m); 212 snd->sb_mbmax -= 213 rcv->sb_mbcnt - unp->unp_conn->unp_mbcnt; 214 unp->unp_conn->unp_mbcnt = rcv->sb_mbcnt; 215 snd->sb_hiwat -= rcv->sb_cc - unp->unp_conn->unp_cc; 216 unp->unp_conn->unp_cc = rcv->sb_cc; 217 sorwakeup(so2); 218 m = 0; 219 #undef snd 220 #undef rcv 221 break; 222 223 default: 224 panic("uipc 4"); 225 } 226 break; 227 228 case PRU_ABORT: 229 unp_drop(unp, ECONNABORTED); 230 break; 231 232 case PRU_SENSE: 233 ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat; 234 if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) { 235 so2 = unp->unp_conn->unp_socket; 236 ((struct stat *) m)->st_blksize += so2->so_rcv.sb_cc; 237 } 238 ((struct stat *) m)->st_dev = NODEV; 239 if (unp->unp_ino == 0) 240 unp->unp_ino = unp_ino++; 241 ((struct stat *) m)->st_ino = unp->unp_ino; 242 return (0); 243 244 case PRU_RCVOOB: 245 return (EOPNOTSUPP); 246 247 case PRU_SENDOOB: 248 error = EOPNOTSUPP; 249 break; 250 251 case PRU_SOCKADDR: 252 if (unp->unp_addr) { 253 nam->m_len = unp->unp_addr->m_len; 254 bcopy(mtod(unp->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_PEERADDR: 261 if (unp->unp_conn && unp->unp_conn->unp_addr) { 262 nam->m_len = unp->unp_conn->unp_addr->m_len; 263 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 264 mtod(nam, caddr_t), (unsigned)nam->m_len); 265 } else 266 nam->m_len = 0; 267 break; 268 269 case PRU_SLOWTIMO: 270 break; 271 272 default: 273 panic("piusrreq"); 274 } 275 release: 276 if (m) 277 m_freem(m); 278 return (error); 279 } 280 281 /* 282 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 283 * for stream sockets, although the total for sender and receiver is 284 * actually only PIPSIZ. 285 * Datagram sockets really use the sendspace as the maximum datagram size, 286 * and don't really want to reserve the sendspace. Their recvspace should 287 * be large enough for at least one max-size datagram plus address. 288 */ 289 #define PIPSIZ 4096 290 u_long unpst_sendspace = PIPSIZ; 291 u_long unpst_recvspace = PIPSIZ; 292 u_long unpdg_sendspace = 2*1024; /* really max datagram size */ 293 u_long unpdg_recvspace = 4*1024; 294 295 int unp_rights; /* file descriptors in flight */ 296 297 unp_attach(so) 298 struct socket *so; 299 { 300 register struct mbuf *m; 301 register struct unpcb *unp; 302 int error; 303 304 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 305 switch (so->so_type) { 306 307 case SOCK_STREAM: 308 error = soreserve(so, unpst_sendspace, unpst_recvspace); 309 break; 310 311 case SOCK_DGRAM: 312 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 313 break; 314 } 315 if (error) 316 return (error); 317 } 318 m = m_getclr(M_DONTWAIT, MT_PCB); 319 if (m == NULL) 320 return (ENOBUFS); 321 unp = mtod(m, struct unpcb *); 322 so->so_pcb = (caddr_t)unp; 323 unp->unp_socket = so; 324 return (0); 325 } 326 327 unp_detach(unp) 328 register struct unpcb *unp; 329 { 330 331 if (unp->unp_inode) { 332 unp->unp_inode->i_socket = 0; 333 irele(unp->unp_inode); 334 unp->unp_inode = 0; 335 } 336 if (unp->unp_conn) 337 unp_disconnect(unp); 338 while (unp->unp_refs) 339 unp_drop(unp->unp_refs, ECONNRESET); 340 soisdisconnected(unp->unp_socket); 341 unp->unp_socket->so_pcb = 0; 342 m_freem(unp->unp_addr); 343 (void) m_free(dtom(unp)); 344 if (unp_rights) 345 unp_gc(); 346 } 347 348 unp_bind(unp, nam) 349 struct unpcb *unp; 350 struct mbuf *nam; 351 { 352 struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 353 register struct inode *ip; 354 register struct nameidata *ndp = &u.u_nd; 355 int error; 356 357 ndp->ni_dirp = soun->sun_path; 358 if (unp->unp_inode != NULL) 359 return (EINVAL); 360 if (nam->m_len == MLEN) { 361 if (*(mtod(nam, caddr_t) + nam->m_len - 1) != 0) 362 return (EINVAL); 363 } else 364 *(mtod(nam, caddr_t) + nam->m_len) = 0; 365 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 366 ndp->ni_nameiop = CREATE | FOLLOW; 367 ndp->ni_segflg = UIO_SYSSPACE; 368 ip = namei(ndp); 369 if (ip) { 370 iput(ip); 371 return (EADDRINUSE); 372 } 373 if (error = u.u_error) { 374 u.u_error = 0; /* XXX */ 375 return (error); 376 } 377 ip = maknode(IFSOCK | 0777, ndp); 378 if (ip == NULL) { 379 error = u.u_error; /* XXX */ 380 u.u_error = 0; /* XXX */ 381 return (error); 382 } 383 ip->i_socket = unp->unp_socket; 384 unp->unp_inode = ip; 385 unp->unp_addr = m_copy(nam, 0, (int)M_COPYALL); 386 iunlock(ip); /* but keep reference */ 387 return (0); 388 } 389 390 unp_connect(so, nam) 391 struct socket *so; 392 struct mbuf *nam; 393 { 394 register struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 395 register struct inode *ip; 396 register struct socket *so2, *so3; 397 register struct nameidata *ndp = &u.u_nd; 398 struct unpcb *unp2, *unp3; 399 int error; 400 401 ndp->ni_dirp = soun->sun_path; 402 if (nam->m_data + nam->m_len == &nam->m_dat[MLEN]) { /* XXX */ 403 if (*(mtod(nam, caddr_t) + nam->m_len - 1) != 0) 404 return (EMSGSIZE); 405 } else 406 *(mtod(nam, caddr_t) + nam->m_len) = 0; 407 ndp->ni_nameiop = LOOKUP | FOLLOW; 408 ndp->ni_segflg = UIO_SYSSPACE; 409 ip = namei(ndp); 410 if (ip == 0) { 411 error = u.u_error; 412 u.u_error = 0; 413 return (error); /* XXX */ 414 } 415 if (access(ip, IWRITE)) { 416 error = u.u_error; 417 u.u_error = 0; /* XXX */ 418 goto bad; 419 } 420 if ((ip->i_mode&IFMT) != IFSOCK) { 421 error = ENOTSOCK; 422 goto bad; 423 } 424 so2 = ip->i_socket; 425 if (so2 == 0) { 426 error = ECONNREFUSED; 427 goto bad; 428 } 429 if (so->so_type != so2->so_type) { 430 error = EPROTOTYPE; 431 goto bad; 432 } 433 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 434 if ((so2->so_options & SO_ACCEPTCONN) == 0 || 435 (so3 = sonewconn(so2)) == 0) { 436 error = ECONNREFUSED; 437 goto bad; 438 } 439 unp2 = sotounpcb(so2); 440 unp3 = sotounpcb(so3); 441 if (unp2->unp_addr) 442 unp3->unp_addr = m_copy(unp2->unp_addr, 0, M_COPYALL); 443 so2 = so3; 444 } 445 error = unp_connect2(so, so2); 446 bad: 447 iput(ip); 448 return (error); 449 } 450 451 unp_connect2(so, so2) 452 register struct socket *so; 453 register struct socket *so2; 454 { 455 register struct unpcb *unp = sotounpcb(so); 456 register struct unpcb *unp2; 457 458 if (so2->so_type != so->so_type) 459 return (EPROTOTYPE); 460 unp2 = sotounpcb(so2); 461 unp->unp_conn = unp2; 462 switch (so->so_type) { 463 464 case SOCK_DGRAM: 465 unp->unp_nextref = unp2->unp_refs; 466 unp2->unp_refs = unp; 467 soisconnected(so); 468 break; 469 470 case SOCK_STREAM: 471 unp2->unp_conn = unp; 472 soisconnected(so2); 473 soisconnected(so); 474 break; 475 476 default: 477 panic("unp_connect2"); 478 } 479 return (0); 480 } 481 482 unp_disconnect(unp) 483 struct unpcb *unp; 484 { 485 register struct unpcb *unp2 = unp->unp_conn; 486 487 if (unp2 == 0) 488 return; 489 unp->unp_conn = 0; 490 switch (unp->unp_socket->so_type) { 491 492 case SOCK_DGRAM: 493 if (unp2->unp_refs == unp) 494 unp2->unp_refs = unp->unp_nextref; 495 else { 496 unp2 = unp2->unp_refs; 497 for (;;) { 498 if (unp2 == 0) 499 panic("unp_disconnect"); 500 if (unp2->unp_nextref == unp) 501 break; 502 unp2 = unp2->unp_nextref; 503 } 504 unp2->unp_nextref = unp->unp_nextref; 505 } 506 unp->unp_nextref = 0; 507 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 508 break; 509 510 case SOCK_STREAM: 511 soisdisconnected(unp->unp_socket); 512 unp2->unp_conn = 0; 513 soisdisconnected(unp2->unp_socket); 514 break; 515 } 516 } 517 518 #ifdef notdef 519 unp_abort(unp) 520 struct unpcb *unp; 521 { 522 523 unp_detach(unp); 524 } 525 #endif 526 527 /*ARGSUSED*/ 528 unp_usrclosed(unp) 529 struct unpcb *unp; 530 { 531 532 } 533 534 unp_drop(unp, errno) 535 struct unpcb *unp; 536 int errno; 537 { 538 struct socket *so = unp->unp_socket; 539 540 so->so_error = errno; 541 unp_disconnect(unp); 542 if (so->so_head) { 543 so->so_pcb = (caddr_t) 0; 544 m_freem(unp->unp_addr); 545 (void) m_free(dtom(unp)); 546 sofree(so); 547 } 548 } 549 550 #ifdef notdef 551 unp_drain() 552 { 553 554 } 555 #endif 556 557 unp_externalize(rights) 558 struct mbuf *rights; 559 { 560 int newfds = rights->m_len / sizeof (int); 561 register int i; 562 register struct file **rp = mtod(rights, struct file **); 563 register struct file *fp; 564 int f; 565 566 if (newfds > ufavail()) { 567 for (i = 0; i < newfds; i++) { 568 fp = *rp; 569 unp_discard(fp); 570 *rp++ = 0; 571 } 572 return (EMSGSIZE); 573 } 574 for (i = 0; i < newfds; i++) { 575 f = ufalloc(0); 576 if (f < 0) 577 panic("unp_externalize"); 578 fp = *rp; 579 u.u_ofile[f] = fp; 580 fp->f_msgcount--; 581 unp_rights--; 582 *(int *)rp++ = f; 583 } 584 return (0); 585 } 586 587 unp_internalize(rights) 588 struct mbuf *rights; 589 { 590 register struct file **rp; 591 int oldfds = rights->m_len / sizeof (int); 592 register int i; 593 register struct file *fp; 594 595 rp = mtod(rights, struct file **); 596 for (i = 0; i < oldfds; i++) 597 if (getf(*(int *)rp++) == 0) 598 return (EBADF); 599 rp = mtod(rights, struct file **); 600 for (i = 0; i < oldfds; i++) { 601 fp = getf(*(int *)rp); 602 *rp++ = fp; 603 fp->f_count++; 604 fp->f_msgcount++; 605 unp_rights++; 606 } 607 return (0); 608 } 609 610 int unp_defer, unp_gcing; 611 int unp_mark(); 612 extern struct domain unixdomain; 613 614 unp_gc() 615 { 616 register struct file *fp; 617 register struct socket *so; 618 619 if (unp_gcing) 620 return; 621 unp_gcing = 1; 622 restart: 623 unp_defer = 0; 624 for (fp = file; fp < fileNFILE; fp++) 625 fp->f_flag &= ~(FMARK|FDEFER); 626 do { 627 for (fp = file; fp < fileNFILE; fp++) { 628 if (fp->f_count == 0) 629 continue; 630 if (fp->f_flag & FDEFER) { 631 fp->f_flag &= ~FDEFER; 632 unp_defer--; 633 } else { 634 if (fp->f_flag & FMARK) 635 continue; 636 if (fp->f_count == fp->f_msgcount) 637 continue; 638 fp->f_flag |= FMARK; 639 } 640 if (fp->f_type != DTYPE_SOCKET || 641 (so = (struct socket *)fp->f_data) == 0) 642 continue; 643 if (so->so_proto->pr_domain != &unixdomain || 644 (so->so_proto->pr_flags&PR_RIGHTS) == 0) 645 continue; 646 if (so->so_rcv.sb_flags & SB_LOCK) { 647 sbwait(&so->so_rcv); 648 goto restart; 649 } 650 unp_scan(so->so_rcv.sb_mb, unp_mark); 651 } 652 } while (unp_defer); 653 for (fp = file; fp < fileNFILE; fp++) { 654 if (fp->f_count == 0) 655 continue; 656 if (fp->f_count == fp->f_msgcount && (fp->f_flag & FMARK) == 0) 657 while (fp->f_msgcount) 658 unp_discard(fp); 659 } 660 unp_gcing = 0; 661 } 662 663 unp_dispose(m) 664 struct mbuf *m; 665 { 666 int unp_discard(); 667 668 if (m) 669 unp_scan(m, unp_discard); 670 } 671 672 unp_scan(m0, op) 673 register struct mbuf *m0; 674 int (*op)(); 675 { 676 register struct mbuf *m; 677 register struct file **rp; 678 register int i; 679 int qfds; 680 681 while (m0) { 682 for (m = m0; m; m = m->m_next) 683 if (m->m_type == MT_RIGHTS && m->m_len) { 684 qfds = m->m_len / sizeof (struct file *); 685 rp = mtod(m, struct file **); 686 for (i = 0; i < qfds; i++) 687 (*op)(*rp++); 688 break; /* XXX, but saves time */ 689 } 690 m0 = m0->m_act; 691 } 692 } 693 694 unp_mark(fp) 695 struct file *fp; 696 { 697 698 if (fp->f_flag & FMARK) 699 return; 700 unp_defer++; 701 fp->f_flag |= (FMARK|FDEFER); 702 } 703 704 unp_discard(fp) 705 struct file *fp; 706 { 707 708 fp->f_msgcount--; 709 unp_rights--; 710 closef(fp); 711 } 712