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 this notice is preserved and that due credit is given 7 * to the University of California at Berkeley. The name of the University 8 * may not be used to endorse or promote products derived from this 9 * software without specific prior written permission. This software 10 * is provided ``as is'' without express or implied warranty. 11 * 12 * @(#)uipc_usrreq.c 7.4 (Berkeley) 02/08/88 13 */ 14 15 #include "param.h" 16 #include "dir.h" 17 #include "user.h" 18 #include "mbuf.h" 19 #include "domain.h" 20 #include "protosw.h" 21 #include "socket.h" 22 #include "socketvar.h" 23 #include "unpcb.h" 24 #include "un.h" 25 #include "inode.h" 26 #include "file.h" 27 #include "stat.h" 28 29 /* 30 * Unix communications domain. 31 * 32 * TODO: 33 * SEQPACKET, RDM 34 * rethink name space problems 35 * need a proper out-of-band 36 */ 37 struct sockaddr sun_noname = { AF_UNIX }; 38 ino_t unp_ino; /* prototype for fake inode numbers */ 39 40 /*ARGSUSED*/ 41 uipc_usrreq(so, req, m, nam, rights) 42 struct socket *so; 43 int req; 44 struct mbuf *m, *nam, *rights; 45 { 46 struct unpcb *unp = sotounpcb(so); 47 register struct socket *so2; 48 int error = 0; 49 50 if (req == PRU_CONTROL) 51 return (EOPNOTSUPP); 52 if (req != PRU_SEND && rights && rights->m_len) { 53 error = EOPNOTSUPP; 54 goto release; 55 } 56 if (unp == 0 && req != PRU_ATTACH) { 57 error = EINVAL; 58 goto release; 59 } 60 switch (req) { 61 62 case PRU_ATTACH: 63 if (unp) { 64 error = EISCONN; 65 break; 66 } 67 error = unp_attach(so); 68 break; 69 70 case PRU_DETACH: 71 unp_detach(unp); 72 break; 73 74 case PRU_BIND: 75 error = unp_bind(unp, nam); 76 break; 77 78 case PRU_LISTEN: 79 if (unp->unp_inode == 0) 80 error = EINVAL; 81 break; 82 83 case PRU_CONNECT: 84 error = unp_connect(so, nam); 85 break; 86 87 case PRU_CONNECT2: 88 error = unp_connect2(so, (struct socket *)nam); 89 break; 90 91 case PRU_DISCONNECT: 92 unp_disconnect(unp); 93 break; 94 95 case PRU_ACCEPT: 96 /* 97 * Pass back name of connected socket, 98 * if it was bound and we are still connected 99 * (our peer may have closed already!). 100 */ 101 if (unp->unp_conn && unp->unp_conn->unp_addr) { 102 nam->m_len = unp->unp_conn->unp_addr->m_len; 103 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 104 mtod(nam, caddr_t), (unsigned)nam->m_len); 105 } else { 106 nam->m_len = sizeof(sun_noname); 107 *(mtod(nam, struct sockaddr *)) = sun_noname; 108 } 109 break; 110 111 case PRU_SHUTDOWN: 112 socantsendmore(so); 113 unp_usrclosed(unp); 114 break; 115 116 case PRU_RCVD: 117 switch (so->so_type) { 118 119 case SOCK_DGRAM: 120 panic("uipc 1"); 121 /*NOTREACHED*/ 122 123 case SOCK_STREAM: 124 #define rcv (&so->so_rcv) 125 #define snd (&so2->so_snd) 126 if (unp->unp_conn == 0) 127 break; 128 so2 = unp->unp_conn->unp_socket; 129 /* 130 * Adjust backpressure on sender 131 * and wakeup any waiting to write. 132 */ 133 snd->sb_mbmax += unp->unp_mbcnt - rcv->sb_mbcnt; 134 unp->unp_mbcnt = rcv->sb_mbcnt; 135 snd->sb_hiwat += unp->unp_cc - rcv->sb_cc; 136 unp->unp_cc = rcv->sb_cc; 137 sowwakeup(so2); 138 #undef snd 139 #undef rcv 140 break; 141 142 default: 143 panic("uipc 2"); 144 } 145 break; 146 147 case PRU_SEND: 148 if (rights) { 149 error = unp_internalize(rights); 150 if (error) 151 break; 152 } 153 switch (so->so_type) { 154 155 case SOCK_DGRAM: { 156 struct sockaddr *from; 157 158 if (nam) { 159 if (unp->unp_conn) { 160 error = EISCONN; 161 break; 162 } 163 error = unp_connect(so, nam); 164 if (error) 165 break; 166 } else { 167 if (unp->unp_conn == 0) { 168 error = ENOTCONN; 169 break; 170 } 171 } 172 so2 = unp->unp_conn->unp_socket; 173 if (unp->unp_addr) 174 from = mtod(unp->unp_addr, struct sockaddr *); 175 else 176 from = &sun_noname; 177 if (sbspace(&so2->so_rcv) > 0 && 178 sbappendaddr(&so2->so_rcv, from, m, rights)) { 179 sorwakeup(so2); 180 m = 0; 181 } else 182 error = ENOBUFS; 183 if (nam) 184 unp_disconnect(unp); 185 break; 186 } 187 188 case SOCK_STREAM: 189 #define rcv (&so2->so_rcv) 190 #define snd (&so->so_snd) 191 if (so->so_state & SS_CANTSENDMORE) { 192 error = EPIPE; 193 break; 194 } 195 if (unp->unp_conn == 0) 196 panic("uipc 3"); 197 so2 = unp->unp_conn->unp_socket; 198 /* 199 * Send to paired receive port, and then reduce 200 * send buffer hiwater marks to maintain backpressure. 201 * Wake up readers. 202 */ 203 if (rights) 204 (void)sbappendrights(rcv, m, rights); 205 else 206 sbappend(rcv, m); 207 snd->sb_mbmax -= 208 rcv->sb_mbcnt - unp->unp_conn->unp_mbcnt; 209 unp->unp_conn->unp_mbcnt = rcv->sb_mbcnt; 210 snd->sb_hiwat -= rcv->sb_cc - unp->unp_conn->unp_cc; 211 unp->unp_conn->unp_cc = rcv->sb_cc; 212 sorwakeup(so2); 213 m = 0; 214 #undef snd 215 #undef rcv 216 break; 217 218 default: 219 panic("uipc 4"); 220 } 221 break; 222 223 case PRU_ABORT: 224 unp_drop(unp, ECONNABORTED); 225 break; 226 227 case PRU_SENSE: 228 ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat; 229 if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) { 230 so2 = unp->unp_conn->unp_socket; 231 ((struct stat *) m)->st_blksize += so2->so_rcv.sb_cc; 232 } 233 ((struct stat *) m)->st_dev = NODEV; 234 if (unp->unp_ino == 0) 235 unp->unp_ino = unp_ino++; 236 ((struct stat *) m)->st_ino = unp->unp_ino; 237 return (0); 238 239 case PRU_RCVOOB: 240 return (EOPNOTSUPP); 241 242 case PRU_SENDOOB: 243 error = EOPNOTSUPP; 244 break; 245 246 case PRU_SOCKADDR: 247 break; 248 249 case PRU_PEERADDR: 250 if (unp->unp_conn && unp->unp_conn->unp_addr) { 251 nam->m_len = unp->unp_conn->unp_addr->m_len; 252 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 253 mtod(nam, caddr_t), (unsigned)nam->m_len); 254 } 255 break; 256 257 case PRU_SLOWTIMO: 258 break; 259 260 default: 261 panic("piusrreq"); 262 } 263 release: 264 if (m) 265 m_freem(m); 266 return (error); 267 } 268 269 /* 270 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 271 * for stream sockets, although the total for sender and receiver is 272 * actually only PIPSIZ. 273 * Datagram sockets really use the sendspace as the maximum datagram size, 274 * and don't really want to reserve the sendspace. Their recvspace should 275 * be large enough for at least one max-size datagram plus address. 276 */ 277 #define PIPSIZ 4096 278 int unpst_sendspace = PIPSIZ; 279 int unpst_recvspace = PIPSIZ; 280 int unpdg_sendspace = 2*1024; /* really max datagram size */ 281 int unpdg_recvspace = 4*1024; 282 283 int unp_rights; /* file descriptors in flight */ 284 285 unp_attach(so) 286 struct socket *so; 287 { 288 register struct mbuf *m; 289 register struct unpcb *unp; 290 int error; 291 292 switch (so->so_type) { 293 294 case SOCK_STREAM: 295 error = soreserve(so, unpst_sendspace, unpst_recvspace); 296 break; 297 298 case SOCK_DGRAM: 299 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 300 break; 301 } 302 if (error) 303 return (error); 304 m = m_getclr(M_DONTWAIT, MT_PCB); 305 if (m == NULL) 306 return (ENOBUFS); 307 unp = mtod(m, struct unpcb *); 308 so->so_pcb = (caddr_t)unp; 309 unp->unp_socket = so; 310 return (0); 311 } 312 313 unp_detach(unp) 314 register struct unpcb *unp; 315 { 316 317 if (unp->unp_inode) { 318 unp->unp_inode->i_socket = 0; 319 irele(unp->unp_inode); 320 unp->unp_inode = 0; 321 } 322 if (unp->unp_conn) 323 unp_disconnect(unp); 324 while (unp->unp_refs) 325 unp_drop(unp->unp_refs, ECONNRESET); 326 soisdisconnected(unp->unp_socket); 327 unp->unp_socket->so_pcb = 0; 328 m_freem(unp->unp_addr); 329 (void) m_free(dtom(unp)); 330 if (unp_rights) 331 unp_gc(); 332 } 333 334 unp_bind(unp, nam) 335 struct unpcb *unp; 336 struct mbuf *nam; 337 { 338 struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 339 register struct inode *ip; 340 register struct nameidata *ndp = &u.u_nd; 341 int error; 342 343 ndp->ni_dirp = soun->sun_path; 344 if (unp->unp_inode != NULL || nam->m_len == MLEN) 345 return (EINVAL); 346 *(mtod(nam, caddr_t) + nam->m_len) = 0; 347 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 348 ndp->ni_nameiop = CREATE | FOLLOW; 349 ndp->ni_segflg = UIO_SYSSPACE; 350 ip = namei(ndp); 351 if (ip) { 352 iput(ip); 353 return (EADDRINUSE); 354 } 355 if (error = u.u_error) { 356 u.u_error = 0; /* XXX */ 357 return (error); 358 } 359 ip = maknode(IFSOCK | 0777, ndp); 360 if (ip == NULL) { 361 error = u.u_error; /* XXX */ 362 u.u_error = 0; /* XXX */ 363 return (error); 364 } 365 ip->i_socket = unp->unp_socket; 366 unp->unp_inode = ip; 367 unp->unp_addr = m_copy(nam, 0, (int)M_COPYALL); 368 iunlock(ip); /* but keep reference */ 369 return (0); 370 } 371 372 unp_connect(so, nam) 373 struct socket *so; 374 struct mbuf *nam; 375 { 376 register struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 377 register struct inode *ip; 378 int error; 379 register struct socket *so2; 380 register struct nameidata *ndp = &u.u_nd; 381 382 ndp->ni_dirp = soun->sun_path; 383 if (nam->m_len + (nam->m_off - MMINOFF) == MLEN) 384 return (EMSGSIZE); 385 *(mtod(nam, caddr_t) + nam->m_len) = 0; 386 ndp->ni_nameiop = LOOKUP | FOLLOW; 387 ndp->ni_segflg = UIO_SYSSPACE; 388 ip = namei(ndp); 389 if (ip == 0) { 390 error = u.u_error; 391 u.u_error = 0; 392 return (error); /* XXX */ 393 } 394 if (access(ip, IWRITE)) { 395 error = u.u_error; 396 u.u_error = 0; /* XXX */ 397 goto bad; 398 } 399 if ((ip->i_mode&IFMT) != IFSOCK) { 400 error = ENOTSOCK; 401 goto bad; 402 } 403 so2 = ip->i_socket; 404 if (so2 == 0) { 405 error = ECONNREFUSED; 406 goto bad; 407 } 408 if (so->so_type != so2->so_type) { 409 error = EPROTOTYPE; 410 goto bad; 411 } 412 if (so->so_proto->pr_flags & PR_CONNREQUIRED && 413 ((so2->so_options&SO_ACCEPTCONN) == 0 || 414 (so2 = sonewconn(so2)) == 0)) { 415 error = ECONNREFUSED; 416 goto bad; 417 } 418 error = unp_connect2(so, so2); 419 bad: 420 iput(ip); 421 return (error); 422 } 423 424 unp_connect2(so, so2) 425 register struct socket *so; 426 register struct socket *so2; 427 { 428 register struct unpcb *unp = sotounpcb(so); 429 register struct unpcb *unp2; 430 431 if (so2->so_type != so->so_type) 432 return (EPROTOTYPE); 433 unp2 = sotounpcb(so2); 434 unp->unp_conn = unp2; 435 switch (so->so_type) { 436 437 case SOCK_DGRAM: 438 unp->unp_nextref = unp2->unp_refs; 439 unp2->unp_refs = unp; 440 soisconnected(so); 441 break; 442 443 case SOCK_STREAM: 444 unp2->unp_conn = unp; 445 soisconnected(so2); 446 soisconnected(so); 447 break; 448 449 default: 450 panic("unp_connect2"); 451 } 452 return (0); 453 } 454 455 unp_disconnect(unp) 456 struct unpcb *unp; 457 { 458 register struct unpcb *unp2 = unp->unp_conn; 459 460 if (unp2 == 0) 461 return; 462 unp->unp_conn = 0; 463 switch (unp->unp_socket->so_type) { 464 465 case SOCK_DGRAM: 466 if (unp2->unp_refs == unp) 467 unp2->unp_refs = unp->unp_nextref; 468 else { 469 unp2 = unp2->unp_refs; 470 for (;;) { 471 if (unp2 == 0) 472 panic("unp_disconnect"); 473 if (unp2->unp_nextref == unp) 474 break; 475 unp2 = unp2->unp_nextref; 476 } 477 unp2->unp_nextref = unp->unp_nextref; 478 } 479 unp->unp_nextref = 0; 480 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 481 break; 482 483 case SOCK_STREAM: 484 soisdisconnected(unp->unp_socket); 485 unp2->unp_conn = 0; 486 soisdisconnected(unp2->unp_socket); 487 break; 488 } 489 } 490 491 #ifdef notdef 492 unp_abort(unp) 493 struct unpcb *unp; 494 { 495 496 unp_detach(unp); 497 } 498 #endif 499 500 /*ARGSUSED*/ 501 unp_usrclosed(unp) 502 struct unpcb *unp; 503 { 504 505 } 506 507 unp_drop(unp, errno) 508 struct unpcb *unp; 509 int errno; 510 { 511 struct socket *so = unp->unp_socket; 512 513 so->so_error = errno; 514 unp_disconnect(unp); 515 if (so->so_head) { 516 so->so_pcb = (caddr_t) 0; 517 m_freem(unp->unp_addr); 518 (void) m_free(dtom(unp)); 519 sofree(so); 520 } 521 } 522 523 #ifdef notdef 524 unp_drain() 525 { 526 527 } 528 #endif 529 530 unp_externalize(rights) 531 struct mbuf *rights; 532 { 533 int newfds = rights->m_len / sizeof (int); 534 register int i; 535 register struct file **rp = mtod(rights, struct file **); 536 register struct file *fp; 537 int f; 538 539 if (newfds > ufavail()) { 540 for (i = 0; i < newfds; i++) { 541 fp = *rp; 542 unp_discard(fp); 543 *rp++ = 0; 544 } 545 return (EMSGSIZE); 546 } 547 for (i = 0; i < newfds; i++) { 548 f = ufalloc(0); 549 if (f < 0) 550 panic("unp_externalize"); 551 fp = *rp; 552 u.u_ofile[f] = fp; 553 fp->f_msgcount--; 554 unp_rights--; 555 *(int *)rp++ = f; 556 } 557 return (0); 558 } 559 560 unp_internalize(rights) 561 struct mbuf *rights; 562 { 563 register struct file **rp; 564 int oldfds = rights->m_len / sizeof (int); 565 register int i; 566 register struct file *fp; 567 568 rp = mtod(rights, struct file **); 569 for (i = 0; i < oldfds; i++) 570 if (getf(*(int *)rp++) == 0) 571 return (EBADF); 572 rp = mtod(rights, struct file **); 573 for (i = 0; i < oldfds; i++) { 574 fp = getf(*(int *)rp); 575 *rp++ = fp; 576 fp->f_count++; 577 fp->f_msgcount++; 578 unp_rights++; 579 } 580 return (0); 581 } 582 583 int unp_defer, unp_gcing; 584 int unp_mark(); 585 extern struct domain unixdomain; 586 587 unp_gc() 588 { 589 register struct file *fp; 590 register struct socket *so; 591 592 if (unp_gcing) 593 return; 594 unp_gcing = 1; 595 restart: 596 unp_defer = 0; 597 for (fp = file; fp < fileNFILE; fp++) 598 fp->f_flag &= ~(FMARK|FDEFER); 599 do { 600 for (fp = file; fp < fileNFILE; fp++) { 601 if (fp->f_count == 0) 602 continue; 603 if (fp->f_flag & FDEFER) { 604 fp->f_flag &= ~FDEFER; 605 unp_defer--; 606 } else { 607 if (fp->f_flag & FMARK) 608 continue; 609 if (fp->f_count == fp->f_msgcount) 610 continue; 611 fp->f_flag |= FMARK; 612 } 613 if (fp->f_type != DTYPE_SOCKET || 614 (so = (struct socket *)fp->f_data) == 0) 615 continue; 616 if (so->so_proto->pr_domain != &unixdomain || 617 (so->so_proto->pr_flags&PR_RIGHTS) == 0) 618 continue; 619 if (so->so_rcv.sb_flags & SB_LOCK) { 620 sbwait(&so->so_rcv); 621 goto restart; 622 } 623 unp_scan(so->so_rcv.sb_mb, unp_mark); 624 } 625 } while (unp_defer); 626 for (fp = file; fp < fileNFILE; fp++) { 627 if (fp->f_count == 0) 628 continue; 629 if (fp->f_count == fp->f_msgcount && (fp->f_flag & FMARK) == 0) 630 while (fp->f_msgcount) 631 unp_discard(fp); 632 } 633 unp_gcing = 0; 634 } 635 636 unp_dispose(m) 637 struct mbuf *m; 638 { 639 int unp_discard(); 640 641 if (m) 642 unp_scan(m, unp_discard); 643 } 644 645 unp_scan(m0, op) 646 register struct mbuf *m0; 647 int (*op)(); 648 { 649 register struct mbuf *m; 650 register struct file **rp; 651 register int i; 652 int qfds; 653 654 while (m0) { 655 for (m = m0; m; m = m->m_next) 656 if (m->m_type == MT_RIGHTS && m->m_len) { 657 qfds = m->m_len / sizeof (struct file *); 658 rp = mtod(m, struct file **); 659 for (i = 0; i < qfds; i++) 660 (*op)(*rp++); 661 break; /* XXX, but saves time */ 662 } 663 m0 = m0->m_act; 664 } 665 } 666 667 unp_mark(fp) 668 struct file *fp; 669 { 670 671 if (fp->f_flag & FMARK) 672 return; 673 unp_defer++; 674 fp->f_flag |= (FMARK|FDEFER); 675 } 676 677 unp_discard(fp) 678 struct file *fp; 679 { 680 681 fp->f_msgcount--; 682 unp_rights--; 683 closef(fp); 684 } 685