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