1 /* uipc_socket.c 4.77 83/08/20 */ 2 3 #include "../h/param.h" 4 #include "../h/systm.h" 5 #include "../h/dir.h" 6 #include "../h/user.h" 7 #include "../h/proc.h" 8 #include "../h/file.h" 9 #include "../h/inode.h" 10 #include "../h/buf.h" 11 #include "../h/mbuf.h" 12 #include "../h/un.h" 13 #include "../h/protosw.h" 14 #include "../h/socket.h" 15 #include "../h/socketvar.h" 16 #include "../h/stat.h" 17 #include "../h/ioctl.h" 18 #include "../h/uio.h" 19 #include "../net/route.h" 20 #include "../netinet/in.h" 21 #include "../net/if.h" 22 23 /* 24 * Socket operation routines. 25 * These routines are called by the routines in 26 * sys_socket.c or from a system process, and 27 * implement the semantics of socket operations by 28 * switching out to the protocol specific routines. 29 * 30 * TODO: 31 * sostat 32 * test socketpair 33 * PR_RIGHTS 34 * clean up select, async 35 * out-of-band is a kludge 36 */ 37 /*ARGSUSED*/ 38 socreate(dom, aso, type, proto) 39 struct socket **aso; 40 register int type; 41 int proto; 42 { 43 register struct protosw *prp; 44 register struct socket *so; 45 register struct mbuf *m; 46 register int error; 47 48 if (proto) 49 prp = pffindproto(dom, proto); 50 else 51 prp = pffindtype(dom, type); 52 if (prp == 0) 53 return (EPROTONOSUPPORT); 54 if (prp->pr_type != type) 55 return (EPROTOTYPE); 56 m = m_getclr(M_WAIT, MT_SOCKET); 57 if (m == 0) 58 return (ENOBUFS); 59 so = mtod(m, struct socket *); 60 so->so_options = 0; 61 so->so_state = 0; 62 so->so_type = type; 63 if (u.u_uid == 0) 64 so->so_state = SS_PRIV; 65 so->so_proto = prp; 66 error = 67 (*prp->pr_usrreq)(so, PRU_ATTACH, 68 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0); 69 if (error) { 70 so->so_state |= SS_NOFDREF; 71 sofree(so); 72 return (error); 73 } 74 *aso = so; 75 return (0); 76 } 77 78 sobind(so, nam) 79 struct socket *so; 80 struct mbuf *nam; 81 { 82 int s = splnet(); 83 int error; 84 85 error = 86 (*so->so_proto->pr_usrreq)(so, PRU_BIND, 87 (struct mbuf *)0, nam, (struct mbuf *)0); 88 splx(s); 89 return (error); 90 } 91 92 solisten(so, backlog) 93 register struct socket *so; 94 int backlog; 95 { 96 int s = splnet(), error; 97 98 error = 99 (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, 100 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0); 101 if (error) { 102 splx(s); 103 return (error); 104 } 105 if (so->so_q == 0) { 106 so->so_q = so; 107 so->so_q0 = so; 108 so->so_options |= SO_ACCEPTCONN; 109 } 110 if (backlog < 0) 111 backlog = 0; 112 so->so_qlimit = MIN(backlog, SOMAXCONN); 113 splx(s); 114 return (0); 115 } 116 117 sofree(so) 118 register struct socket *so; 119 { 120 121 if (so->so_head) { 122 if (!soqremque(so, 0) && !soqremque(so, 1)) 123 panic("sofree dq"); 124 so->so_head = 0; 125 } 126 if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) 127 return; 128 sbrelease(&so->so_snd); 129 sorflush(so); 130 (void) m_free(dtom(so)); 131 } 132 133 /* 134 * Close a socket on last file table reference removal. 135 * Initiate disconnect if connected. 136 * Free socket when disconnect complete. 137 */ 138 soclose(so) 139 register struct socket *so; 140 { 141 int s = splnet(); /* conservative */ 142 int error; 143 144 if (so->so_options & SO_ACCEPTCONN) { 145 while (so->so_q0 != so) 146 (void) soabort(so->so_q0); 147 while (so->so_q != so) 148 (void) soabort(so->so_q); 149 } 150 if (so->so_pcb == 0) 151 goto discard; 152 if (so->so_state & SS_ISCONNECTED) { 153 if ((so->so_state & SS_ISDISCONNECTING) == 0) { 154 error = sodisconnect(so, (struct mbuf *)0); 155 if (error) 156 goto drop; 157 } 158 if (so->so_options & SO_LINGER) { 159 if ((so->so_state & SS_ISDISCONNECTING) && 160 (so->so_state & SS_NBIO)) 161 goto drop; 162 while (so->so_state & SS_ISCONNECTED) 163 sleep((caddr_t)&so->so_timeo, PZERO+1); 164 } 165 } 166 drop: 167 if (so->so_pcb) { 168 int error2 = 169 (*so->so_proto->pr_usrreq)(so, PRU_DETACH, 170 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0); 171 if (error == 0) 172 error = error2; 173 } 174 discard: 175 if (so->so_state & SS_NOFDREF) 176 panic("soclose: NOFDREF"); 177 so->so_state |= SS_NOFDREF; 178 sofree(so); 179 splx(s); 180 return (error); 181 } 182 183 /* 184 * Must be called at splnet... 185 */ 186 soabort(so) 187 struct socket *so; 188 { 189 190 return ( 191 (*so->so_proto->pr_usrreq)(so, PRU_ABORT, 192 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0)); 193 } 194 195 soaccept(so, nam) 196 register struct socket *so; 197 struct mbuf *nam; 198 { 199 int s = splnet(); 200 int error; 201 202 if ((so->so_state & SS_NOFDREF) == 0) 203 panic("soaccept: !NOFDREF"); 204 so->so_state &= ~SS_NOFDREF; 205 error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT, 206 (struct mbuf *)0, nam, (struct mbuf *)0); 207 splx(s); 208 return (error); 209 } 210 211 soconnect(so, nam) 212 register struct socket *so; 213 struct mbuf *nam; 214 { 215 int s = splnet(); 216 int error; 217 218 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) { 219 error = EISCONN; 220 goto bad; 221 } 222 error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT, 223 (struct mbuf *)0, nam, (struct mbuf *)0); 224 bad: 225 splx(s); 226 return (error); 227 } 228 229 soconnect2(so1, so2) 230 register struct socket *so1; 231 struct socket *so2; 232 { 233 int s = splnet(); 234 int error; 235 236 error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2, 237 (struct mbuf *)0, (struct mbuf *)so2, (struct mbuf *)0); 238 splx(s); 239 return (error); 240 } 241 242 sodisconnect(so, nam) 243 register struct socket *so; 244 struct mbuf *nam; 245 { 246 int s = splnet(); 247 int error; 248 249 if ((so->so_state & SS_ISCONNECTED) == 0) { 250 error = ENOTCONN; 251 goto bad; 252 } 253 if (so->so_state & SS_ISDISCONNECTING) { 254 error = EALREADY; 255 goto bad; 256 } 257 error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, 258 (struct mbuf *)0, nam, (struct mbuf *)0); 259 bad: 260 splx(s); 261 return (error); 262 } 263 264 /* 265 * Send on a socket. 266 * If send must go all at once and message is larger than 267 * send buffering, then hard error. 268 * Lock against other senders. 269 * If must go all at once and not enough room now, then 270 * inform user that this would block and do nothing. 271 */ 272 sosend(so, nam, uio, flags, rights) 273 register struct socket *so; 274 struct mbuf *nam; 275 register struct uio *uio; 276 int flags; 277 struct mbuf *rights; 278 { 279 struct mbuf *top = 0; 280 register struct mbuf *m, **mp = ⊤ 281 register int space; 282 int len, error = 0, s, dontroute; 283 284 if (sosendallatonce(so) && uio->uio_resid > so->so_snd.sb_hiwat) 285 return (EMSGSIZE); 286 dontroute = 287 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && 288 (so->so_proto->pr_flags & PR_ATOMIC); 289 restart: 290 sblock(&so->so_snd); 291 #define snderr(errno) { error = errno; splx(s); goto release; } 292 293 u.u_ru.ru_msgsnd++; 294 again: 295 s = splnet(); 296 if (so->so_state & SS_CANTSENDMORE) { 297 psignal(u.u_procp, SIGPIPE); 298 snderr(EPIPE); 299 } 300 if (so->so_error) { 301 error = so->so_error; 302 so->so_error = 0; /* ??? */ 303 splx(s); 304 goto release; 305 } 306 if ((so->so_state & SS_ISCONNECTED) == 0) { 307 if (so->so_proto->pr_flags & PR_CONNREQUIRED) 308 snderr(ENOTCONN); 309 if (nam == 0) 310 snderr(EDESTADDRREQ); 311 } 312 if (top) { 313 if (dontroute) 314 so->so_options |= SO_DONTROUTE; 315 error = (*so->so_proto->pr_usrreq)(so, 316 (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND, 317 top, (caddr_t)nam, rights); 318 if (dontroute) 319 so->so_options &= ~SO_DONTROUTE; 320 top = 0; 321 if (error) { 322 splx(s); 323 goto release; 324 } 325 mp = ⊤ 326 } 327 if (uio->uio_resid == 0) { 328 splx(s); 329 goto release; 330 } 331 if (flags & MSG_OOB) 332 space = 1024; 333 else { 334 space = sbspace(&so->so_snd); 335 if (space <= 0 || 336 sosendallatonce(so) && space < uio->uio_resid) { 337 if (so->so_state & SS_NBIO) 338 snderr(EWOULDBLOCK); 339 sbunlock(&so->so_snd); 340 sbwait(&so->so_snd); 341 splx(s); 342 goto restart; 343 } 344 } 345 splx(s); 346 while (uio->uio_resid > 0 && space > 0) { 347 register struct iovec *iov = uio->uio_iov; 348 349 if (iov->iov_len == 0) { 350 uio->uio_iov++; 351 uio->uio_iovcnt--; 352 if (uio->uio_iovcnt < 0) 353 panic("sosend"); 354 continue; 355 } 356 MGET(m, M_WAIT, MT_DATA); 357 if (m == NULL) { 358 error = ENOBUFS; /* SIGPIPE? */ 359 goto release; 360 } 361 if (iov->iov_len >= CLBYTES && space >= CLBYTES) { 362 register struct mbuf *p; 363 MCLGET(p, 1); 364 if (p == 0) 365 goto nopages; 366 m->m_off = (int)p - (int)m; 367 len = CLBYTES; 368 } else { 369 nopages: 370 len = MIN(MLEN, iov->iov_len); 371 } 372 error = uiomove(mtod(m, caddr_t), len, UIO_WRITE, uio); 373 m->m_len = len; 374 *mp = m; 375 if (error) 376 goto release; 377 mp = &m->m_next; 378 if (flags & MSG_OOB) 379 space -= len; 380 else 381 space = sbspace(&so->so_snd); 382 } 383 goto again; 384 385 release: 386 sbunlock(&so->so_snd); 387 if (top) 388 m_freem(top); 389 return (error); 390 } 391 392 soreceive(so, aname, uio, flags, rightsp) 393 register struct socket *so; 394 struct mbuf **aname; 395 register struct uio *uio; 396 int flags; 397 struct mbuf **rightsp; 398 { 399 register struct mbuf *m, *n; 400 register int len, error = 0, s, eor, tomark; 401 struct protosw *pr = so->so_proto; 402 int moff; 403 404 if (rightsp) 405 *rightsp = 0; 406 if (aname) 407 *aname = 0; 408 if (flags & MSG_OOB) { 409 m = m_get(M_WAIT, MT_DATA); 410 if (m == 0) 411 return (ENOBUFS); 412 error = (*pr->pr_usrreq)(so, PRU_RCVOOB, 413 m, (struct mbuf *)0, (struct mbuf *)0); 414 if (error) 415 goto bad; 416 do { 417 len = uio->uio_resid; 418 if (len > m->m_len) 419 len = m->m_len; 420 error = 421 uiomove(mtod(m, caddr_t), (int)len, UIO_READ, uio); 422 m = m_free(m); 423 } while (uio->uio_resid && error == 0 && m); 424 bad: 425 if (m) 426 m_freem(m); 427 return (error); 428 } 429 430 restart: 431 sblock(&so->so_rcv); 432 s = splnet(); 433 434 #define rcverr(errno) { error = errno; splx(s); goto release; } 435 if (so->so_rcv.sb_cc == 0) { 436 if (so->so_error) { 437 error = so->so_error; 438 so->so_error = 0; 439 splx(s); 440 goto release; 441 } 442 if (so->so_state & SS_CANTRCVMORE) { 443 splx(s); 444 goto release; 445 } 446 if ((so->so_state & SS_ISCONNECTED) == 0 && 447 (so->so_proto->pr_flags & PR_CONNREQUIRED)) 448 rcverr(ENOTCONN); 449 if (so->so_state & SS_NBIO) 450 rcverr(EWOULDBLOCK); 451 sbunlock(&so->so_rcv); 452 sbwait(&so->so_rcv); 453 splx(s); 454 goto restart; 455 } 456 u.u_ru.ru_msgrcv++; 457 m = so->so_rcv.sb_mb; 458 if (m == 0) 459 panic("receive"); 460 if (pr->pr_flags & PR_ADDR) { 461 if ((flags & MSG_PEEK) == 0) { 462 so->so_rcv.sb_cc -= m->m_len; 463 so->so_rcv.sb_mbcnt -= MSIZE; 464 } 465 if (aname) { 466 if (flags & MSG_PEEK) { 467 *aname = m_copy(m, 0, m->m_len); 468 if (*aname == NULL) 469 panic("receive 2"); 470 } else 471 *aname = m; 472 m = m->m_next; 473 (*aname)->m_next = 0; 474 } else 475 if (flags & MSG_PEEK) 476 m = m->m_next; 477 else 478 m = m_free(m); 479 if (m == 0) 480 panic("receive 2a"); 481 if (rightsp) { 482 if (m->m_len) 483 *rightsp = m_copy(m, 0, m->m_len); 484 else { 485 *rightsp = m_get(M_DONTWAIT, MT_SONAME); 486 if (*rightsp) 487 (*rightsp)->m_len = 0; 488 } 489 if (*rightsp == NULL) 490 panic("receive 2b"); 491 } 492 if (flags & MSG_PEEK) 493 m = m->m_next; 494 else { 495 so->so_rcv.sb_cc -= m->m_len; 496 so->so_rcv.sb_mbcnt -= MSIZE; 497 m = m_free(m); 498 } 499 if (m == 0) 500 panic("receive 3"); 501 if ((flags & MSG_PEEK) == 0) 502 so->so_rcv.sb_mb = m; 503 } 504 eor = 0; 505 moff = 0; 506 tomark = so->so_oobmark; 507 do { 508 if (uio->uio_resid <= 0) 509 break; 510 len = uio->uio_resid; 511 so->so_state &= ~SS_RCVATMARK; 512 if (tomark && len > tomark) 513 len = tomark; 514 if (moff+len > m->m_len - moff) 515 len = m->m_len - moff; 516 splx(s); 517 error = 518 uiomove(mtod(m, caddr_t) + moff, (int)len, UIO_READ, uio); 519 s = splnet(); 520 if (len == m->m_len) { 521 eor = (int)m->m_act; 522 if (flags & MSG_PEEK) 523 m = m->m_next; 524 else { 525 sbfree(&so->so_rcv, m); 526 MFREE(m, n); 527 m = n; 528 so->so_rcv.sb_mb = m; 529 } 530 moff = 0; 531 } else { 532 if (flags & MSG_PEEK) 533 moff += len; 534 else { 535 m->m_off += len; 536 m->m_len -= len; 537 so->so_rcv.sb_cc -= len; 538 } 539 } 540 if ((flags & MSG_PEEK) == 0 && so->so_oobmark) { 541 so->so_oobmark -= len; 542 if (so->so_oobmark == 0) { 543 so->so_state |= SS_RCVATMARK; 544 break; 545 } 546 } 547 if (tomark) { 548 tomark -= len; 549 if (tomark == 0) 550 break; 551 } 552 } while (m && error == 0 && !eor); 553 if (flags & MSG_PEEK) 554 goto release; 555 if ((so->so_proto->pr_flags & PR_ATOMIC) && eor == 0) 556 do { 557 if (m == 0) 558 panic("receive 4"); 559 sbfree(&so->so_rcv, m); 560 eor = (int)m->m_act; 561 so->so_rcv.sb_mb = m->m_next; 562 MFREE(m, n); 563 m = n; 564 } while (eor == 0); 565 if ((so->so_proto->pr_flags & PR_WANTRCVD) && so->so_pcb) 566 (*so->so_proto->pr_usrreq)(so, PRU_RCVD, 567 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0); 568 release: 569 sbunlock(&so->so_rcv); 570 if (error == 0 && rightsp && 571 *rightsp && so->so_proto->pr_family == AF_UNIX) 572 error = unp_externalize(*rightsp); 573 splx(s); 574 return (error); 575 } 576 577 soshutdown(so, how) 578 register struct socket *so; 579 register int how; 580 { 581 register struct protosw *pr = so->so_proto; 582 583 how++; 584 if (how & FREAD) 585 sorflush(so); 586 if (how & FWRITE) 587 return ((*pr->pr_usrreq)(so, PRU_SHUTDOWN, 588 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0)); 589 return (0); 590 } 591 592 sorflush(so) 593 register struct socket *so; 594 { 595 register struct sockbuf *sb = &so->so_rcv; 596 register struct protosw *pr = so->so_proto; 597 register int s; 598 struct sockbuf asb; 599 600 sblock(sb); 601 s = splimp(); 602 socantrcvmore(so); 603 sbunlock(sb); 604 asb = *sb; 605 bzero((caddr_t)sb, sizeof (*sb)); 606 splx(s); 607 if (pr->pr_family == AF_UNIX && (pr->pr_flags & PR_RIGHTS)) 608 unp_scan(asb.sb_mb, unp_discard); 609 sbrelease(&asb); 610 } 611 612 sosetopt(so, level, optname, m) 613 register struct socket *so; 614 int level, optname; 615 register struct mbuf *m; 616 { 617 618 if (level != SOL_SOCKET) 619 return (EINVAL); /* XXX */ 620 switch (optname) { 621 622 case SO_DEBUG: 623 case SO_KEEPALIVE: 624 case SO_DONTROUTE: 625 case SO_USELOOPBACK: 626 case SO_REUSEADDR: 627 so->so_options |= optname; 628 break; 629 630 case SO_LINGER: 631 if (m == NULL || m->m_len != sizeof (int)) 632 return (EINVAL); 633 so->so_options |= SO_LINGER; 634 so->so_linger = *mtod(m, int *); 635 break; 636 637 case SO_DONTLINGER: 638 so->so_options &= ~SO_LINGER; 639 so->so_linger = 0; 640 break; 641 642 default: 643 return (EINVAL); 644 } 645 return (0); 646 } 647 648 sogetopt(so, level, optname, m) 649 register struct socket *so; 650 int level, optname; 651 register struct mbuf *m; 652 { 653 654 if (level != SOL_SOCKET) 655 return (EINVAL); /* XXX */ 656 switch (optname) { 657 658 case SO_USELOOPBACK: 659 case SO_DONTROUTE: 660 case SO_DEBUG: 661 case SO_KEEPALIVE: 662 case SO_LINGER: 663 case SO_REUSEADDR: 664 if ((so->so_options & optname) == 0) 665 return (ENOPROTOOPT); 666 if (optname == SO_LINGER && m != NULL) { 667 *mtod(m, int *) = so->so_linger; 668 m->m_len = sizeof (so->so_linger); 669 } 670 break; 671 672 default: 673 return (EINVAL); 674 } 675 return (0); 676 } 677 678 sohasoutofband(so) 679 register struct socket *so; 680 { 681 682 if (so->so_pgrp == 0) 683 return; 684 if (so->so_pgrp > 0) 685 gsignal(so->so_pgrp, SIGURG); 686 else { 687 struct proc *p = pfind(-so->so_pgrp); 688 689 if (p) 690 psignal(p, SIGURG); 691 } 692 } 693