1 /* 2 * Copyright (c) 1982 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 * 6 * @(#)uipc_usrreq.c 6.23 (Berkeley) 06/02/86 7 */ 8 9 #include "param.h" 10 #include "dir.h" 11 #include "user.h" 12 #include "mbuf.h" 13 #include "domain.h" 14 #include "protosw.h" 15 #include "socket.h" 16 #include "socketvar.h" 17 #include "unpcb.h" 18 #include "un.h" 19 #include "inode.h" 20 #include "file.h" 21 #include "stat.h" 22 23 /* 24 * Unix communications domain. 25 * 26 * TODO: 27 * SEQPACKET, RDM 28 * rethink name space problems 29 * need a proper out-of-band 30 */ 31 struct sockaddr sun_noname = { AF_UNIX }; 32 ino_t unp_ino; /* prototype for fake inode numbers */ 33 34 /*ARGSUSED*/ 35 uipc_usrreq(so, req, m, nam, rights) 36 struct socket *so; 37 int req; 38 struct mbuf *m, *nam, *rights; 39 { 40 struct unpcb *unp = sotounpcb(so); 41 register struct socket *so2; 42 int error = 0; 43 44 if (req == PRU_CONTROL) 45 return (EOPNOTSUPP); 46 if (req != PRU_SEND && rights && rights->m_len) { 47 error = EOPNOTSUPP; 48 goto release; 49 } 50 if (unp == 0 && req != PRU_ATTACH) { 51 error = EINVAL; 52 goto release; 53 } 54 switch (req) { 55 56 case PRU_ATTACH: 57 if (unp) { 58 error = EISCONN; 59 break; 60 } 61 error = unp_attach(so); 62 break; 63 64 case PRU_DETACH: 65 unp_detach(unp); 66 break; 67 68 case PRU_BIND: 69 error = unp_bind(unp, nam); 70 break; 71 72 case PRU_LISTEN: 73 if (unp->unp_inode == 0) 74 error = EINVAL; 75 break; 76 77 case PRU_CONNECT: 78 error = unp_connect(so, nam); 79 break; 80 81 case PRU_CONNECT2: 82 error = unp_connect2(so, (struct socket *)nam); 83 break; 84 85 case PRU_DISCONNECT: 86 unp_disconnect(unp); 87 break; 88 89 case PRU_ACCEPT: 90 /* 91 * Pass back name of connected socket, 92 * if it was bound and we are still connected 93 * (our peer may have closed already!). 94 */ 95 if (unp->unp_conn && unp->unp_conn->unp_addr) { 96 nam->m_len = unp->unp_conn->unp_addr->m_len; 97 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 98 mtod(nam, caddr_t), (unsigned)nam->m_len); 99 } else { 100 nam->m_len = sizeof(sun_noname); 101 *(mtod(nam, struct sockaddr *)) = sun_noname; 102 } 103 break; 104 105 case PRU_SHUTDOWN: 106 socantsendmore(so); 107 unp_usrclosed(unp); 108 break; 109 110 case PRU_RCVD: 111 switch (so->so_type) { 112 113 case SOCK_DGRAM: 114 panic("uipc 1"); 115 /*NOTREACHED*/ 116 117 case SOCK_STREAM: 118 #define rcv (&so->so_rcv) 119 #define snd (&so2->so_snd) 120 if (unp->unp_conn == 0) 121 break; 122 so2 = unp->unp_conn->unp_socket; 123 /* 124 * Adjust backpressure on sender 125 * and wakeup any waiting to write. 126 */ 127 snd->sb_mbmax += unp->unp_mbcnt - rcv->sb_mbcnt; 128 unp->unp_mbcnt = rcv->sb_mbcnt; 129 snd->sb_hiwat += unp->unp_cc - rcv->sb_cc; 130 unp->unp_cc = rcv->sb_cc; 131 sowwakeup(so2); 132 #undef snd 133 #undef rcv 134 break; 135 136 default: 137 panic("uipc 2"); 138 } 139 break; 140 141 case PRU_SEND: 142 if (rights) { 143 error = unp_internalize(rights); 144 if (error) 145 break; 146 } 147 switch (so->so_type) { 148 149 case SOCK_DGRAM: { 150 struct sockaddr *from; 151 152 if (nam) { 153 if (unp->unp_conn) { 154 error = EISCONN; 155 break; 156 } 157 error = unp_connect(so, nam); 158 if (error) 159 break; 160 } else { 161 if (unp->unp_conn == 0) { 162 error = ENOTCONN; 163 break; 164 } 165 } 166 so2 = unp->unp_conn->unp_socket; 167 if (unp->unp_addr) 168 from = mtod(unp->unp_addr, struct sockaddr *); 169 else 170 from = &sun_noname; 171 if (sbspace(&so2->so_rcv) > 0 && 172 sbappendaddr(&so2->so_rcv, from, m, rights)) { 173 sorwakeup(so2); 174 m = 0; 175 } else 176 error = ENOBUFS; 177 if (nam) 178 unp_disconnect(unp); 179 break; 180 } 181 182 case SOCK_STREAM: 183 #define rcv (&so2->so_rcv) 184 #define snd (&so->so_snd) 185 if (so->so_state & SS_CANTSENDMORE) { 186 error = EPIPE; 187 break; 188 } 189 if (unp->unp_conn == 0) 190 panic("uipc 3"); 191 so2 = unp->unp_conn->unp_socket; 192 /* 193 * Send to paired receive port, and then reduce 194 * send buffer hiwater marks to maintain backpressure. 195 * Wake up readers. 196 */ 197 if (rights) 198 (void)sbappendrights(rcv, m, rights); 199 else 200 sbappend(rcv, m); 201 snd->sb_mbmax -= 202 rcv->sb_mbcnt - unp->unp_conn->unp_mbcnt; 203 unp->unp_conn->unp_mbcnt = rcv->sb_mbcnt; 204 snd->sb_hiwat -= rcv->sb_cc - unp->unp_conn->unp_cc; 205 unp->unp_conn->unp_cc = rcv->sb_cc; 206 sorwakeup(so2); 207 m = 0; 208 #undef snd 209 #undef rcv 210 break; 211 212 default: 213 panic("uipc 4"); 214 } 215 break; 216 217 case PRU_ABORT: 218 unp_drop(unp, ECONNABORTED); 219 break; 220 221 case PRU_SENSE: 222 ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat; 223 if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) { 224 so2 = unp->unp_conn->unp_socket; 225 ((struct stat *) m)->st_blksize += so2->so_rcv.sb_cc; 226 } 227 ((struct stat *) m)->st_dev = NODEV; 228 if (unp->unp_ino == 0) 229 unp->unp_ino = unp_ino++; 230 ((struct stat *) m)->st_ino = unp->unp_ino; 231 return (0); 232 233 case PRU_RCVOOB: 234 return (EOPNOTSUPP); 235 236 case PRU_SENDOOB: 237 error = EOPNOTSUPP; 238 break; 239 240 case PRU_SOCKADDR: 241 break; 242 243 case PRU_PEERADDR: 244 if (unp->unp_conn && unp->unp_conn->unp_addr) { 245 nam->m_len = unp->unp_conn->unp_addr->m_len; 246 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t), 247 mtod(m, caddr_t), (unsigned)m->m_len); 248 } 249 break; 250 251 case PRU_SLOWTIMO: 252 break; 253 254 default: 255 panic("piusrreq"); 256 } 257 release: 258 if (m) 259 m_freem(m); 260 return (error); 261 } 262 263 /* 264 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 265 * for stream sockets, although the total for sender and receiver is 266 * actually only PIPSIZ. 267 * Datagram sockets really use the sendspace as the maximum datagram size, 268 * and don't really want to reserve the sendspace. Their recvspace should 269 * be large enough for at least one max-size datagram plus address. 270 */ 271 #define PIPSIZ 4096 272 int unpst_sendspace = PIPSIZ; 273 int unpst_recvspace = PIPSIZ; 274 int unpdg_sendspace = 2*1024; /* really max datagram size */ 275 int unpdg_recvspace = 4*1024; 276 277 int unp_rights; /* file descriptors in flight */ 278 279 unp_attach(so) 280 struct socket *so; 281 { 282 register struct mbuf *m; 283 register struct unpcb *unp; 284 int error; 285 286 switch (so->so_type) { 287 288 case SOCK_STREAM: 289 error = soreserve(so, unpst_sendspace, unpst_recvspace); 290 break; 291 292 case SOCK_DGRAM: 293 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 294 break; 295 } 296 if (error) 297 return (error); 298 m = m_getclr(M_DONTWAIT, MT_PCB); 299 if (m == NULL) 300 return (ENOBUFS); 301 unp = mtod(m, struct unpcb *); 302 so->so_pcb = (caddr_t)unp; 303 unp->unp_socket = so; 304 return (0); 305 } 306 307 unp_detach(unp) 308 register struct unpcb *unp; 309 { 310 311 if (unp->unp_inode) { 312 unp->unp_inode->i_socket = 0; 313 irele(unp->unp_inode); 314 unp->unp_inode = 0; 315 } 316 if (unp->unp_conn) 317 unp_disconnect(unp); 318 while (unp->unp_refs) 319 unp_drop(unp->unp_refs, ECONNRESET); 320 soisdisconnected(unp->unp_socket); 321 unp->unp_socket->so_pcb = 0; 322 m_freem(unp->unp_addr); 323 (void) m_free(dtom(unp)); 324 if (unp_rights) 325 unp_gc(); 326 } 327 328 unp_bind(unp, nam) 329 struct unpcb *unp; 330 struct mbuf *nam; 331 { 332 struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 333 register struct inode *ip; 334 register struct nameidata *ndp = &u.u_nd; 335 int error; 336 337 ndp->ni_dirp = soun->sun_path; 338 if (unp->unp_inode != NULL || nam->m_len == MLEN) 339 return (EINVAL); 340 *(mtod(nam, caddr_t) + nam->m_len) = 0; 341 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 342 ndp->ni_nameiop = CREATE | FOLLOW; 343 ndp->ni_segflg = UIO_SYSSPACE; 344 ip = namei(ndp); 345 if (ip) { 346 iput(ip); 347 return (EADDRINUSE); 348 } 349 if (error = u.u_error) { 350 u.u_error = 0; /* XXX */ 351 return (error); 352 } 353 ip = maknode(IFSOCK | 0777, ndp); 354 if (ip == NULL) { 355 error = u.u_error; /* XXX */ 356 u.u_error = 0; /* XXX */ 357 return (error); 358 } 359 ip->i_socket = unp->unp_socket; 360 unp->unp_inode = ip; 361 unp->unp_addr = m_copy(nam, 0, (int)M_COPYALL); 362 iunlock(ip); /* but keep reference */ 363 return (0); 364 } 365 366 unp_connect(so, nam) 367 struct socket *so; 368 struct mbuf *nam; 369 { 370 register struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 371 register struct inode *ip; 372 int error; 373 register struct socket *so2; 374 register struct nameidata *ndp = &u.u_nd; 375 376 ndp->ni_dirp = soun->sun_path; 377 if (nam->m_len + (nam->m_off - MMINOFF) == MLEN) 378 return (EMSGSIZE); 379 *(mtod(nam, caddr_t) + nam->m_len) = 0; 380 ndp->ni_nameiop = LOOKUP | FOLLOW; 381 ndp->ni_segflg = UIO_SYSSPACE; 382 ip = namei(ndp); 383 if (ip == 0) { 384 error = u.u_error; 385 u.u_error = 0; 386 return (error); /* XXX */ 387 } 388 if (access(ip, IWRITE)) { 389 error = u.u_error; 390 u.u_error = 0; /* XXX */ 391 goto bad; 392 } 393 if ((ip->i_mode&IFMT) != IFSOCK) { 394 error = ENOTSOCK; 395 goto bad; 396 } 397 so2 = ip->i_socket; 398 if (so2 == 0) { 399 error = ECONNREFUSED; 400 goto bad; 401 } 402 if (so->so_type != so2->so_type) { 403 error = EPROTOTYPE; 404 goto bad; 405 } 406 if (so->so_proto->pr_flags & PR_CONNREQUIRED && 407 ((so2->so_options&SO_ACCEPTCONN) == 0 || 408 (so2 = sonewconn(so2)) == 0)) { 409 error = ECONNREFUSED; 410 goto bad; 411 } 412 error = unp_connect2(so, so2); 413 bad: 414 iput(ip); 415 return (error); 416 } 417 418 unp_connect2(so, so2) 419 register struct socket *so; 420 register struct socket *so2; 421 { 422 register struct unpcb *unp = sotounpcb(so); 423 register struct unpcb *unp2; 424 425 if (so2->so_type != so->so_type) 426 return (EPROTOTYPE); 427 unp2 = sotounpcb(so2); 428 unp->unp_conn = unp2; 429 switch (so->so_type) { 430 431 case SOCK_DGRAM: 432 unp->unp_nextref = unp2->unp_refs; 433 unp2->unp_refs = unp; 434 soisconnected(so); 435 break; 436 437 case SOCK_STREAM: 438 unp2->unp_conn = unp; 439 soisconnected(so2); 440 soisconnected(so); 441 break; 442 443 default: 444 panic("unp_connect2"); 445 } 446 return (0); 447 } 448 449 unp_disconnect(unp) 450 struct unpcb *unp; 451 { 452 register struct unpcb *unp2 = unp->unp_conn; 453 454 if (unp2 == 0) 455 return; 456 unp->unp_conn = 0; 457 switch (unp->unp_socket->so_type) { 458 459 case SOCK_DGRAM: 460 if (unp2->unp_refs == unp) 461 unp2->unp_refs = unp->unp_nextref; 462 else { 463 unp2 = unp2->unp_refs; 464 for (;;) { 465 if (unp2 == 0) 466 panic("unp_disconnect"); 467 if (unp2->unp_nextref == unp) 468 break; 469 unp2 = unp2->unp_nextref; 470 } 471 unp2->unp_nextref = unp->unp_nextref; 472 } 473 unp->unp_nextref = 0; 474 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 475 break; 476 477 case SOCK_STREAM: 478 soisdisconnected(unp->unp_socket); 479 unp2->unp_conn = 0; 480 soisdisconnected(unp2->unp_socket); 481 break; 482 } 483 } 484 485 #ifdef notdef 486 unp_abort(unp) 487 struct unpcb *unp; 488 { 489 490 unp_detach(unp); 491 } 492 #endif 493 494 /*ARGSUSED*/ 495 unp_usrclosed(unp) 496 struct unpcb *unp; 497 { 498 499 } 500 501 unp_drop(unp, errno) 502 struct unpcb *unp; 503 int errno; 504 { 505 struct socket *so = unp->unp_socket; 506 507 so->so_error = errno; 508 unp_disconnect(unp); 509 if (so->so_head) { 510 so->so_pcb = (caddr_t) 0; 511 m_freem(unp->unp_addr); 512 (void) m_free(dtom(unp)); 513 sofree(so); 514 } 515 } 516 517 #ifdef notdef 518 unp_drain() 519 { 520 521 } 522 #endif 523 524 unp_externalize(rights) 525 struct mbuf *rights; 526 { 527 int newfds = rights->m_len / sizeof (int); 528 register int i; 529 register struct file **rp = mtod(rights, struct file **); 530 register struct file *fp; 531 int f; 532 533 if (newfds > ufavail()) { 534 for (i = 0; i < newfds; i++) { 535 fp = *rp; 536 unp_discard(fp); 537 *rp++ = 0; 538 } 539 return (EMSGSIZE); 540 } 541 for (i = 0; i < newfds; i++) { 542 f = ufalloc(0); 543 if (f < 0) 544 panic("unp_externalize"); 545 fp = *rp; 546 u.u_ofile[f] = fp; 547 fp->f_msgcount--; 548 unp_rights--; 549 *(int *)rp++ = f; 550 } 551 return (0); 552 } 553 554 unp_internalize(rights) 555 struct mbuf *rights; 556 { 557 register struct file **rp; 558 int oldfds = rights->m_len / sizeof (int); 559 register int i; 560 register struct file *fp; 561 562 rp = mtod(rights, struct file **); 563 for (i = 0; i < oldfds; i++) 564 if (getf(*(int *)rp++) == 0) 565 return (EBADF); 566 rp = mtod(rights, struct file **); 567 for (i = 0; i < oldfds; i++) { 568 fp = getf(*(int *)rp); 569 *rp++ = fp; 570 fp->f_count++; 571 fp->f_msgcount++; 572 unp_rights++; 573 } 574 return (0); 575 } 576 577 int unp_defer, unp_gcing; 578 int unp_mark(); 579 extern struct domain unixdomain; 580 581 unp_gc() 582 { 583 register struct file *fp; 584 register struct socket *so; 585 586 if (unp_gcing) 587 return; 588 unp_gcing = 1; 589 restart: 590 unp_defer = 0; 591 for (fp = file; fp < fileNFILE; fp++) 592 fp->f_flag &= ~(FMARK|FDEFER); 593 do { 594 for (fp = file; fp < fileNFILE; fp++) { 595 if (fp->f_count == 0) 596 continue; 597 if (fp->f_flag & FDEFER) { 598 fp->f_flag &= ~FDEFER; 599 unp_defer--; 600 } else { 601 if (fp->f_flag & FMARK) 602 continue; 603 if (fp->f_count == fp->f_msgcount) 604 continue; 605 fp->f_flag |= FMARK; 606 } 607 if (fp->f_type != DTYPE_SOCKET) 608 continue; 609 so = (struct socket *)fp->f_data; 610 if (so->so_proto->pr_domain != &unixdomain || 611 (so->so_proto->pr_flags&PR_RIGHTS) == 0) 612 continue; 613 if (so->so_rcv.sb_flags & SB_LOCK) { 614 sbwait(&so->so_rcv); 615 goto restart; 616 } 617 unp_scan(so->so_rcv.sb_mb, unp_mark); 618 } 619 } while (unp_defer); 620 for (fp = file; fp < fileNFILE; fp++) { 621 if (fp->f_count == 0) 622 continue; 623 if (fp->f_count == fp->f_msgcount && (fp->f_flag & FMARK) == 0) 624 while (fp->f_msgcount) 625 unp_discard(fp); 626 } 627 unp_gcing = 0; 628 } 629 630 unp_dispose(m) 631 struct mbuf *m; 632 { 633 int unp_discard(); 634 635 if (m) 636 unp_scan(m, unp_discard); 637 } 638 639 unp_scan(m0, op) 640 register struct mbuf *m0; 641 int (*op)(); 642 { 643 register struct mbuf *m; 644 register struct file **rp; 645 register int i; 646 int qfds; 647 648 while (m0) { 649 for (m = m0; m; m = m->m_next) 650 if (m->m_type == MT_RIGHTS && m->m_len) { 651 qfds = m->m_len / sizeof (struct file *); 652 rp = mtod(m, struct file **); 653 for (i = 0; i < qfds; i++) 654 (*op)(*rp++); 655 break; /* XXX, but saves time */ 656 } 657 m0 = m0->m_act; 658 } 659 } 660 661 unp_mark(fp) 662 struct file *fp; 663 { 664 665 if (fp->f_flag & FMARK) 666 return; 667 unp_defer++; 668 fp->f_flag |= (FMARK|FDEFER); 669 } 670 671 unp_discard(fp) 672 struct file *fp; 673 { 674 675 fp->f_msgcount--; 676 unp_rights--; 677 closef(fp); 678 } 679