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 6.21 (Berkeley) 02/23/86 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 break; 245 246 case PRU_SLOWTIMO: 247 break; 248 249 default: 250 panic("piusrreq"); 251 } 252 release: 253 if (m) 254 m_freem(m); 255 return (error); 256 } 257 258 /* 259 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 260 * for stream sockets, although the total for sender and receiver is 261 * actually only PIPSIZ. 262 * Datagram sockets really use the sendspace as the maximum datagram size, 263 * and don't really want to reserve the sendspace. Their recvspace should 264 * be large enough for at least one max-size datagram plus address. 265 */ 266 #define PIPSIZ 4096 267 int unpst_sendspace = PIPSIZ; 268 int unpst_recvspace = PIPSIZ; 269 int unpdg_sendspace = 2*1024; /* really max datagram size */ 270 int unpdg_recvspace = 4*1024; 271 272 int unp_rights; /* file descriptors in flight */ 273 274 unp_attach(so) 275 struct socket *so; 276 { 277 register struct mbuf *m; 278 register struct unpcb *unp; 279 int error; 280 281 switch (so->so_type) { 282 283 case SOCK_STREAM: 284 error = soreserve(so, unpst_sendspace, unpst_recvspace); 285 break; 286 287 case SOCK_DGRAM: 288 error = soreserve(so, unpdg_sendspace, unpdg_recvspace); 289 break; 290 } 291 if (error) 292 return (error); 293 m = m_getclr(M_DONTWAIT, MT_PCB); 294 if (m == NULL) 295 return (ENOBUFS); 296 unp = mtod(m, struct unpcb *); 297 so->so_pcb = (caddr_t)unp; 298 unp->unp_socket = so; 299 return (0); 300 } 301 302 unp_detach(unp) 303 register struct unpcb *unp; 304 { 305 306 if (unp->unp_inode) { 307 unp->unp_inode->i_socket = 0; 308 irele(unp->unp_inode); 309 unp->unp_inode = 0; 310 } 311 if (unp->unp_conn) 312 unp_disconnect(unp); 313 while (unp->unp_refs) 314 unp_drop(unp->unp_refs, ECONNRESET); 315 soisdisconnected(unp->unp_socket); 316 unp->unp_socket->so_pcb = 0; 317 m_freem(unp->unp_addr); 318 (void) m_free(dtom(unp)); 319 if (unp_rights) 320 unp_gc(); 321 } 322 323 unp_bind(unp, nam) 324 struct unpcb *unp; 325 struct mbuf *nam; 326 { 327 struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 328 register struct inode *ip; 329 register struct nameidata *ndp = &u.u_nd; 330 int error; 331 332 ndp->ni_dirp = soun->sun_path; 333 if (unp->unp_inode != NULL || nam->m_len == MLEN) 334 return (EINVAL); 335 *(mtod(nam, caddr_t) + nam->m_len) = 0; 336 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */ 337 ndp->ni_nameiop = CREATE | FOLLOW; 338 ndp->ni_segflg = UIO_SYSSPACE; 339 ip = namei(ndp); 340 if (ip) { 341 iput(ip); 342 return (EADDRINUSE); 343 } 344 if (error = u.u_error) { 345 u.u_error = 0; /* XXX */ 346 return (error); 347 } 348 ip = maknode(IFSOCK | 0777, ndp); 349 if (ip == NULL) { 350 error = u.u_error; /* XXX */ 351 u.u_error = 0; /* XXX */ 352 return (error); 353 } 354 ip->i_socket = unp->unp_socket; 355 unp->unp_inode = ip; 356 unp->unp_addr = m_copy(nam, 0, (int)M_COPYALL); 357 iunlock(ip); /* but keep reference */ 358 return (0); 359 } 360 361 unp_connect(so, nam) 362 struct socket *so; 363 struct mbuf *nam; 364 { 365 register struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *); 366 register struct inode *ip; 367 int error; 368 register struct socket *so2; 369 register struct nameidata *ndp = &u.u_nd; 370 371 ndp->ni_dirp = soun->sun_path; 372 if (nam->m_len + (nam->m_off - MMINOFF) == MLEN) 373 return (EMSGSIZE); 374 *(mtod(nam, caddr_t) + nam->m_len) = 0; 375 ndp->ni_nameiop = LOOKUP | FOLLOW; 376 ndp->ni_segflg = UIO_SYSSPACE; 377 ip = namei(ndp); 378 if (ip == 0) { 379 error = u.u_error; 380 u.u_error = 0; 381 return (error); /* XXX */ 382 } 383 if (access(ip, IWRITE)) { 384 error = u.u_error; 385 u.u_error = 0; /* XXX */ 386 goto bad; 387 } 388 if ((ip->i_mode&IFMT) != IFSOCK) { 389 error = ENOTSOCK; 390 goto bad; 391 } 392 so2 = ip->i_socket; 393 if (so2 == 0) { 394 error = ECONNREFUSED; 395 goto bad; 396 } 397 if (so->so_type != so2->so_type) { 398 error = EPROTOTYPE; 399 goto bad; 400 } 401 if (so->so_proto->pr_flags & PR_CONNREQUIRED && 402 ((so2->so_options&SO_ACCEPTCONN) == 0 || 403 (so2 = sonewconn(so2)) == 0)) { 404 error = ECONNREFUSED; 405 goto bad; 406 } 407 error = unp_connect2(so, so2); 408 bad: 409 iput(ip); 410 return (error); 411 } 412 413 unp_connect2(so, so2) 414 register struct socket *so; 415 register struct socket *so2; 416 { 417 register struct unpcb *unp = sotounpcb(so); 418 register struct unpcb *unp2; 419 420 if (so2->so_type != so->so_type) 421 return (EPROTOTYPE); 422 unp2 = sotounpcb(so2); 423 unp->unp_conn = unp2; 424 switch (so->so_type) { 425 426 case SOCK_DGRAM: 427 unp->unp_nextref = unp2->unp_refs; 428 unp2->unp_refs = unp; 429 soisconnected(so); 430 break; 431 432 case SOCK_STREAM: 433 unp2->unp_conn = unp; 434 soisconnected(so2); 435 soisconnected(so); 436 break; 437 438 default: 439 panic("unp_connect2"); 440 } 441 return (0); 442 } 443 444 unp_disconnect(unp) 445 struct unpcb *unp; 446 { 447 register struct unpcb *unp2 = unp->unp_conn; 448 449 if (unp2 == 0) 450 return; 451 unp->unp_conn = 0; 452 switch (unp->unp_socket->so_type) { 453 454 case SOCK_DGRAM: 455 if (unp2->unp_refs == unp) 456 unp2->unp_refs = unp->unp_nextref; 457 else { 458 unp2 = unp2->unp_refs; 459 for (;;) { 460 if (unp2 == 0) 461 panic("unp_disconnect"); 462 if (unp2->unp_nextref == unp) 463 break; 464 unp2 = unp2->unp_nextref; 465 } 466 unp2->unp_nextref = unp->unp_nextref; 467 } 468 unp->unp_nextref = 0; 469 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 470 break; 471 472 case SOCK_STREAM: 473 soisdisconnected(unp->unp_socket); 474 unp2->unp_conn = 0; 475 soisdisconnected(unp2->unp_socket); 476 break; 477 } 478 } 479 480 #ifdef notdef 481 unp_abort(unp) 482 struct unpcb *unp; 483 { 484 485 unp_detach(unp); 486 } 487 #endif 488 489 /*ARGSUSED*/ 490 unp_usrclosed(unp) 491 struct unpcb *unp; 492 { 493 494 } 495 496 unp_drop(unp, errno) 497 struct unpcb *unp; 498 int errno; 499 { 500 struct socket *so = unp->unp_socket; 501 502 so->so_error = errno; 503 unp_disconnect(unp); 504 if (so->so_head) { 505 so->so_pcb = (caddr_t) 0; 506 m_freem(unp->unp_addr); 507 (void) m_free(dtom(unp)); 508 sofree(so); 509 } 510 } 511 512 #ifdef notdef 513 unp_drain() 514 { 515 516 } 517 #endif 518 519 unp_externalize(rights) 520 struct mbuf *rights; 521 { 522 int newfds = rights->m_len / sizeof (int); 523 register int i; 524 register struct file **rp = mtod(rights, struct file **); 525 register struct file *fp; 526 int f; 527 528 if (newfds > ufavail()) { 529 for (i = 0; i < newfds; i++) { 530 fp = *rp; 531 unp_discard(fp); 532 *rp++ = 0; 533 } 534 return (EMSGSIZE); 535 } 536 for (i = 0; i < newfds; i++) { 537 f = ufalloc(0); 538 if (f < 0) 539 panic("unp_externalize"); 540 fp = *rp; 541 u.u_ofile[f] = fp; 542 fp->f_msgcount--; 543 unp_rights--; 544 *(int *)rp++ = f; 545 } 546 return (0); 547 } 548 549 unp_internalize(rights) 550 struct mbuf *rights; 551 { 552 register struct file **rp; 553 int oldfds = rights->m_len / sizeof (int); 554 register int i; 555 register struct file *fp; 556 557 rp = mtod(rights, struct file **); 558 for (i = 0; i < oldfds; i++) 559 if (getf(*(int *)rp++) == 0) 560 return (EBADF); 561 rp = mtod(rights, struct file **); 562 for (i = 0; i < oldfds; i++) { 563 fp = getf(*(int *)rp); 564 *rp++ = fp; 565 fp->f_count++; 566 fp->f_msgcount++; 567 unp_rights++; 568 } 569 return (0); 570 } 571 572 int unp_defer, unp_gcing; 573 int unp_mark(); 574 extern struct domain unixdomain; 575 576 unp_gc() 577 { 578 register struct file *fp; 579 register struct socket *so; 580 581 if (unp_gcing) 582 return; 583 unp_gcing = 1; 584 restart: 585 unp_defer = 0; 586 for (fp = file; fp < fileNFILE; fp++) 587 fp->f_flag &= ~(FMARK|FDEFER); 588 do { 589 for (fp = file; fp < fileNFILE; fp++) { 590 if (fp->f_count == 0) 591 continue; 592 if (fp->f_flag & FDEFER) { 593 fp->f_flag &= ~FDEFER; 594 unp_defer--; 595 } else { 596 if (fp->f_flag & FMARK) 597 continue; 598 if (fp->f_count == fp->f_msgcount) 599 continue; 600 fp->f_flag |= FMARK; 601 } 602 if (fp->f_type != DTYPE_SOCKET) 603 continue; 604 so = (struct socket *)fp->f_data; 605 if (so->so_proto->pr_domain != &unixdomain || 606 (so->so_proto->pr_flags&PR_RIGHTS) == 0) 607 continue; 608 if (so->so_rcv.sb_flags & SB_LOCK) { 609 sbwait(&so->so_rcv); 610 goto restart; 611 } 612 unp_scan(so->so_rcv.sb_mb, unp_mark); 613 } 614 } while (unp_defer); 615 for (fp = file; fp < fileNFILE; fp++) { 616 if (fp->f_count == 0) 617 continue; 618 if (fp->f_count == fp->f_msgcount && (fp->f_flag & FMARK) == 0) 619 while (fp->f_msgcount) 620 unp_discard(fp); 621 } 622 unp_gcing = 0; 623 } 624 625 unp_dispose(m) 626 struct mbuf *m; 627 { 628 int unp_discard(); 629 630 if (m) 631 unp_scan(m, unp_discard); 632 } 633 634 unp_scan(m0, op) 635 register struct mbuf *m0; 636 int (*op)(); 637 { 638 register struct mbuf *m; 639 register struct file **rp; 640 register int i; 641 int qfds; 642 643 while (m0) { 644 for (m = m0; m; m = m->m_next) 645 if (m->m_type == MT_RIGHTS && m->m_len) { 646 qfds = m->m_len / sizeof (struct file *); 647 rp = mtod(m, struct file **); 648 for (i = 0; i < qfds; i++) 649 (*op)(*rp++); 650 break; /* XXX, but saves time */ 651 } 652 m0 = m0->m_act; 653 } 654 } 655 656 unp_mark(fp) 657 struct file *fp; 658 { 659 660 if (fp->f_flag & FMARK) 661 return; 662 unp_defer++; 663 fp->f_flag |= (FMARK|FDEFER); 664 } 665 666 unp_discard(fp) 667 struct file *fp; 668 { 669 670 fp->f_msgcount--; 671 unp_rights--; 672 closef(fp); 673 } 674