xref: /csrg-svn/sys/kern/uipc_socket.c (revision 12493)
1 /*	uipc_socket.c	4.74	83/05/18	*/
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/protosw.h"
13 #include "../h/socket.h"
14 #include "../h/socketvar.h"
15 #include "../h/stat.h"
16 #include "../h/ioctl.h"
17 #include "../h/uio.h"
18 #include "../net/route.h"
19 #include "../net/if.h"
20 
21 /*
22  * Socket operation routines.
23  * These routines are called by the routines in
24  * sys_socket.c or from a system process, and
25  * implement the semantics of socket operations by
26  * switching out to the protocol specific routines.
27  */
28 
29 /*ARGSUSED*/
30 socreate(dom, aso, type, proto)
31 	struct socket **aso;
32 	int type, proto;
33 {
34 	register struct protosw *prp;
35 	register struct socket *so;
36 	struct mbuf *m;
37 	int error;
38 
39 	if (proto)
40 		prp = pffindproto(dom, proto);
41 	else
42 		prp = pffindtype(dom, type);
43 	if (prp == 0)
44 		return (EPROTONOSUPPORT);
45 	if (prp->pr_type != type)
46 		return (EPROTOTYPE);
47 	m = m_getclr(M_WAIT, MT_SOCKET);
48 	if (m == 0)
49 		return (ENOBUFS);
50 	so = mtod(m, struct socket *);
51 	so->so_options = SO_LINGER;
52 	so->so_state = 0;
53 	so->so_type = type;
54 	if (u.u_uid == 0)
55 		so->so_state = SS_PRIV;
56 	so->so_proto = prp;
57 	error = (*prp->pr_usrreq)(so, PRU_ATTACH,
58 	    (struct mbuf *)0, (struct mbuf *)0);
59 	if (error) {
60 		so->so_state |= SS_NOFDREF;
61 		sofree(so);
62 		return (error);
63 	}
64 	*aso = so;
65 	return (0);
66 }
67 
68 sobind(so, nam)
69 	struct socket *so;
70 	struct mbuf *nam;
71 {
72 	int s = splnet();
73 	int error;
74 
75 	error =
76 	    (*so->so_proto->pr_usrreq)(so, PRU_BIND, (struct mbuf *)0, nam);
77 	splx(s);
78 	return (error);
79 }
80 
81 solisten(so, backlog)
82 	struct socket *so;
83 	int backlog;
84 {
85 	int s = splnet();
86 	int error;
87 
88 	error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN,
89 	    (struct mbuf *)0, (struct mbuf *)0);
90 	if (error) {
91 		splx(s);
92 		return (error);
93 	}
94 	if (so->so_q == 0) {
95 		so->so_q = so;
96 		so->so_q0 = so;
97 		so->so_options |= SO_ACCEPTCONN;
98 	}
99 	if (backlog < 0)
100 		backlog = 0;
101 #define	SOMAXCONN	5
102 	so->so_qlimit = MIN(backlog, SOMAXCONN);
103 	so->so_options |= SO_NEWFDONCONN;
104 	splx(s);
105 	return (0);
106 }
107 
108 sofree(so)
109 	struct socket *so;
110 {
111 
112 	if (so->so_head) {
113 		if (!soqremque(so, 0) && !soqremque(so, 1))
114 			panic("sofree dq");
115 		so->so_head = 0;
116 	}
117 	if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
118 		return;
119 	sbrelease(&so->so_snd);
120 	sbrelease(&so->so_rcv);
121 	(void) m_free(dtom(so));
122 }
123 
124 /*
125  * Close a socket on last file table reference removal.
126  * Initiate disconnect if connected.
127  * Free socket when disconnect complete.
128  */
129 soclose(so, exiting)
130 	register struct socket *so;
131 	int exiting;
132 {
133 	int s = splnet();		/* conservative */
134 	int error;
135 
136 	if (so->so_options & SO_ACCEPTCONN) {
137 		while (so->so_q0 != so)
138 			(void) soabort(so->so_q0);
139 		while (so->so_q != so)
140 			(void) soabort(so->so_q);
141 	}
142 	if (so->so_pcb == 0)
143 		goto discard;
144 	if (exiting)
145 		so->so_options |= SO_KEEPALIVE;
146 	if (so->so_state & SS_ISCONNECTED) {
147 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
148 			error = sodisconnect(so, (struct mbuf *)0);
149 			if (error) {
150 				if (exiting)
151 					goto drop;
152 				splx(s);
153 				return (error);
154 			}
155 		}
156 		if (so->so_options & SO_LINGER) {
157 			if ((so->so_state & SS_ISDISCONNECTING) &&
158 			    (so->so_state & SS_NBIO) &&
159 			    exiting == 0)
160 				return (EINPROGRESS);
161 			/* should use tsleep here, for at most linger */
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 		error = (*so->so_proto->pr_usrreq)(so, PRU_DETACH,
169 		    (struct mbuf *)0, (struct mbuf *)0);
170 		if (exiting == 0 && error) {
171 			splx(s);
172 			return (error);
173 		}
174 	}
175 discard:
176 	if (so->so_state & SS_NOFDREF)
177 		panic("soclose: NOFDREF");
178 	so->so_state |= SS_NOFDREF;
179 	sofree(so);
180 	splx(s);
181 	return (0);
182 }
183 
184 /*
185  * Must be called at splnet...
186  */
187 soabort(so)
188 	struct socket *so;
189 {
190 	int error;
191 
192 	error = (*so->so_proto->pr_usrreq)(so, PRU_ABORT,
193 	   (struct mbuf *)0, (struct mbuf *)0);
194 	return (error);
195 }
196 
197 /*ARGSUSED*/
198 sostat(so, ub)
199 	struct socket *so;
200 	struct stat *ub;
201 {
202 	struct stat sb;
203 
204 	bzero((caddr_t)&sb, sizeof (sb));		/* XXX */
205 	(void) copyout((caddr_t)&sb, (caddr_t)ub, sizeof (sb));/* XXX */
206 	return (0);					/* XXX */
207 }
208 
209 soaccept(so, nam)
210 	struct socket *so;
211 	struct mbuf *nam;
212 {
213 	int s = splnet();
214 	int error;
215 
216 	if ((so->so_state & SS_NOFDREF) == 0)
217 		panic("soaccept: !NOFDREF");
218 	so->so_state &= ~SS_NOFDREF;
219 	error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT,
220 	    (struct mbuf *)0, nam);
221 	splx(s);
222 	return (error);
223 }
224 
225 soconnect(so, nam)
226 	struct socket *so;
227 	struct mbuf *nam;
228 {
229 	int s = splnet();
230 	int error;
231 
232 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) {
233 		error = EISCONN;
234 		goto bad;
235 	}
236 	error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT,
237 	    (struct mbuf *)0, nam);
238 bad:
239 	splx(s);
240 	return (error);
241 }
242 
243 sodisconnect(so, nam)
244 	struct socket *so;
245 	struct mbuf *nam;
246 {
247 	int s = splnet();
248 	int error;
249 
250 	if ((so->so_state & SS_ISCONNECTED) == 0) {
251 		error = ENOTCONN;
252 		goto bad;
253 	}
254 	if (so->so_state & SS_ISDISCONNECTING) {
255 		error = EALREADY;
256 		goto bad;
257 	}
258 	error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT,
259 	    (struct mbuf *)0, nam);
260 bad:
261 	splx(s);
262 	return (error);
263 }
264 
265 /*
266  * Send on a socket.
267  * If send must go all at once and message is larger than
268  * send buffering, then hard error.
269  * Lock against other senders.
270  * If must go all at once and not enough room now, then
271  * inform user that this would block and do nothing.
272  */
273 sosend(so, nam, uio, flags)
274 	register struct socket *so;
275 	struct mbuf *nam;
276 	struct uio *uio;
277 	int flags;
278 {
279 	struct mbuf *top = 0;
280 	register struct mbuf *m, **mp = &top;
281 	register int len;
282 	int error = 0, space, s, dontroute;
283 
284 	if (sosendallatonce(so) && uio->uio_resid > so->so_snd.sb_hiwat)
285 		return (EMSGSIZE);
286 	dontroute = (flags & SOF_DONTROUTE) &&
287 		(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 & SOF_OOB) ? PRU_SENDOOB : PRU_SEND,
317 		    top, (caddr_t)nam);
318 		if (dontroute)
319 			so->so_options &= ~SO_DONTROUTE;
320 		top = 0;
321 		if (error) {
322 			splx(s);
323 			goto release;
324 		}
325 		mp = &top;
326 	}
327 	if (uio->uio_resid == 0) {
328 		splx(s);
329 		goto release;
330 	}
331 	if (flags & SOF_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 		(void) uiomove(mtod(m, caddr_t), len, UIO_WRITE, uio);
373 		m->m_len = len;
374 		*mp = m;
375 		mp = &m->m_next;
376 		if (flags & SOF_OOB)
377 			space -= len;
378 		else
379 			space = sbspace(&so->so_snd);
380 	}
381 	goto again;
382 
383 release:
384 	sbunlock(&so->so_snd);
385 	if (top)
386 		m_freem(top);
387 	return (error);
388 }
389 
390 soreceive(so, aname, uio, flags)
391 	register struct socket *so;
392 	struct mbuf **aname;
393 	struct uio *uio;
394 	int flags;
395 {
396 	register struct mbuf *m, *n;
397 	int len;
398 	int eor, s, error = 0, moff, tomark;
399 
400 	if (flags & SOF_OOB) {
401 		m = m_get(M_WAIT, MT_DATA);
402 		if (m == NULL)
403 			return (ENOBUFS);
404 		error = (*so->so_proto->pr_usrreq)(so, PRU_RCVOOB,
405 		    m, (struct mbuf *)0);
406 		if (error)
407 			goto bad;
408 		do {
409 			len = uio->uio_resid;
410 			if (len > m->m_len)
411 				len = m->m_len;
412 			error =
413 			    uiomove(mtod(m, caddr_t), (int)len, UIO_READ, uio);
414 			m = m_free(m);
415 		} while (uio->uio_resid && error == 0 && m);
416 bad:
417 		if (m)
418 			m_freem(m);
419 		return (error);
420 	}
421 
422 restart:
423 	sblock(&so->so_rcv);
424 	s = splnet();
425 
426 #define	rcverr(errno)	{ error = errno; splx(s); goto release; }
427 	if (so->so_rcv.sb_cc == 0) {
428 		if (so->so_error) {
429 			error = so->so_error;
430 			so->so_error = 0;
431 			splx(s);
432 			goto release;
433 		}
434 		if (so->so_state & SS_CANTRCVMORE) {
435 			splx(s);
436 			goto release;
437 		}
438 		if ((so->so_state & SS_ISCONNECTED) == 0 &&
439 		    (so->so_proto->pr_flags & PR_CONNREQUIRED))
440 			rcverr(ENOTCONN);
441 		if (so->so_state & SS_NBIO)
442 			rcverr(EWOULDBLOCK);
443 		sbunlock(&so->so_rcv);
444 		sbwait(&so->so_rcv);
445 		splx(s);
446 		goto restart;
447 	}
448 	u.u_ru.ru_msgrcv++;
449 	m = so->so_rcv.sb_mb;
450 	if (m == 0)
451 		panic("receive");
452 	if (so->so_proto->pr_flags & PR_ADDR) {
453 		if ((flags & SOF_PREVIEW) == 0) {
454 			so->so_rcv.sb_cc -= m->m_len;
455 			so->so_rcv.sb_mbcnt -= MSIZE;
456 		}
457 		if (aname) {
458 			if (flags & SOF_PREVIEW) {
459 				*aname = m_copy(m, 0, m->m_len);
460 				if (*aname == NULL)
461 					panic("receive 2");
462 			} else
463 				*aname = m;
464 			m = m->m_next;
465 			(*aname)->m_next = 0;
466 		} else
467 			if (flags & SOF_PREVIEW)
468 				m = m->m_next;
469 			else
470 				m = m_free(m);
471 		if (m == 0)
472 			panic("receive 3");
473 		if ((flags & SOF_PREVIEW) == 0)
474 			so->so_rcv.sb_mb = m;
475 	}
476 	eor = 0;
477 	moff = 0;
478 	tomark = so->so_oobmark;
479 	do {
480 		if (uio->uio_resid <= 0)
481 			break;
482 		len = uio->uio_resid;
483 		so->so_state &= ~SS_RCVATMARK;
484 		if (tomark && len > tomark)
485 			len = tomark;
486 		if (moff+len > m->m_len - moff)
487 			len = m->m_len - moff;
488 		splx(s);
489 		error =
490 		    uiomove(mtod(m, caddr_t) + moff, (int)len, UIO_READ, uio);
491 		s = splnet();
492 		if (len == m->m_len) {
493 			eor = (int)m->m_act;
494 			if (flags & SOF_PREVIEW)
495 				m = m->m_next;
496 			else {
497 				sbfree(&so->so_rcv, m);
498 				MFREE(m, n);
499 				m = n;
500 				so->so_rcv.sb_mb = m;
501 			}
502 			moff = 0;
503 		} else {
504 			if (flags & SOF_PREVIEW)
505 				moff += len;
506 			else {
507 				m->m_off += len;
508 				m->m_len -= len;
509 				so->so_rcv.sb_cc -= len;
510 			}
511 		}
512 		if ((flags & SOF_PREVIEW) == 0 && so->so_oobmark) {
513 			so->so_oobmark -= len;
514 			if (so->so_oobmark == 0) {
515 				so->so_state |= SS_RCVATMARK;
516 				break;
517 			}
518 		}
519 		if (tomark) {
520 			tomark -= len;
521 			if (tomark == 0)
522 				break;
523 		}
524 	} while (m && error == 0 && !eor);
525 	if (flags & SOF_PREVIEW)
526 		goto release;
527 	if ((so->so_proto->pr_flags & PR_ATOMIC) && eor == 0)
528 		do {
529 			if (m == 0)
530 				panic("receive 4");
531 			sbfree(&so->so_rcv, m);
532 			eor = (int)m->m_act;
533 			so->so_rcv.sb_mb = m->m_next;
534 			MFREE(m, n);
535 			m = n;
536 		} while (eor == 0);
537 	if ((so->so_proto->pr_flags & PR_WANTRCVD) && so->so_pcb)
538 		(*so->so_proto->pr_usrreq)(so, PRU_RCVD,
539 		    (struct mbuf *)0, (struct mbuf *)0);
540 release:
541 	sbunlock(&so->so_rcv);
542 	splx(s);
543 	return (error);
544 }
545 
546 soshutdown(so, how)
547 	struct socket *so;
548 	int how;
549 {
550 
551 	how++;
552 	if (how & FREAD) {
553 		int s = splimp();
554 		socantrcvmore(so);
555 		sbflush(&so->so_rcv);
556 		splx(s);
557 	}
558 	if (how & FWRITE)
559 		return ((*so->so_proto->pr_usrreq)(so, PRU_SHUTDOWN,
560 		    (struct mbuf *)0, (struct mbuf *)0));
561 	return (0);
562 }
563 
564 sosetopt(so, level, optname, m)
565 	struct socket *so;
566 	int level, optname;
567 	struct mbuf *m;
568 {
569 
570 	if (level != SOL_SOCKET)
571 		return (EINVAL);	/* XXX */
572 	switch (optname) {
573 
574 	case SO_DEBUG:
575 	case SO_KEEPALIVE:
576 	case SO_DONTROUTE:
577 	case SO_USELOOPBACK:
578 	case SO_REUSEADDR:
579 		so->so_options |= optname;
580 		break;
581 
582 	case SO_LINGER:
583 		if (m == NULL || m->m_len != sizeof (int))
584 			return (EINVAL);
585 		so->so_options |= SO_LINGER;
586 		so->so_linger = *mtod(m, int *);
587 		break;
588 
589 	case SO_DONTLINGER:
590 		so->so_options &= ~SO_LINGER;
591 		so->so_linger = 0;
592 		break;
593 
594 	default:
595 		return (EINVAL);
596 	}
597 	return (0);
598 }
599 
600 sogetopt(so, level, optname, m)
601 	struct socket *so;
602 	int level, optname;
603 	struct mbuf *m;
604 {
605 
606 	if (level != SOL_SOCKET)
607 		return (EINVAL);	/* XXX */
608 	switch (optname) {
609 
610 	case SO_USELOOPBACK:
611 	case SO_DONTROUTE:
612 	case SO_DEBUG:
613 	case SO_KEEPALIVE:
614 	case SO_LINGER:
615 	case SO_REUSEADDR:
616 		if ((so->so_options & optname) == 0)
617 			return (ENOPROTOOPT);
618 		if (optname == SO_LINGER && m != NULL) {
619 			*mtod(m, int *) = so->so_linger;
620 			m->m_len = sizeof (so->so_linger);
621 		}
622 		break;
623 
624 	default:
625 		return (EINVAL);
626 	}
627 	return (0);
628 }
629 
630 sohasoutofband(so)
631 	struct socket *so;
632 {
633 
634 	if (so->so_pgrp == 0)
635 		return;
636 	if (so->so_pgrp > 0)
637 		gsignal(so->so_pgrp, SIGURG);
638 	else {
639 		struct proc *p = pfind(-so->so_pgrp);
640 
641 		if (p)
642 			psignal(p, SIGURG);
643 	}
644 }
645 
646 /*ARGSUSED*/
647 soioctl(so, cmd, data)
648 	register struct socket *so;
649 	int cmd;
650 	register char *data;
651 {
652 
653 	switch (cmd) {
654 
655 	case FIONBIO:
656 		if (*(int *)data)
657 			so->so_state |= SS_NBIO;
658 		else
659 			so->so_state &= ~SS_NBIO;
660 		break;
661 
662 	case FIOASYNC:
663 		if (*(int *)data)
664 			so->so_state |= SS_ASYNC;
665 		else
666 			so->so_state &= ~SS_ASYNC;
667 		break;
668 
669 	case SIOCSPGRP:
670 		so->so_pgrp = *(int *)data;
671 		break;
672 
673 	case SIOCGPGRP:
674 		*(int *)data = so->so_pgrp;
675 		break;
676 
677 	case SIOCATMARK:
678 		*(int *)data = (so->so_state&SS_RCVATMARK) != 0;
679 		break;
680 
681 	/* routing table update calls */
682 	case SIOCADDRT:
683 	case SIOCDELRT:
684 		if (!suser())
685 			return (u.u_error);
686 		return (rtrequest(cmd, (struct rtentry *)data));
687 
688 	/* interface parameter requests */
689 	case SIOCSIFADDR:
690 	case SIOCSIFFLAGS:
691 	case SIOCSIFDSTADDR:
692 		if (!suser())
693 			return (u.u_error);
694 		return (ifrequest(cmd, data));
695 
696 	case SIOCGIFADDR:
697 	case SIOCGIFFLAGS:
698 	case SIOCGIFDSTADDR:
699 		return (ifrequest(cmd, data));
700 
701 	case SIOCGIFCONF:
702 		return (ifconf(cmd, data));
703 
704 	/* type/protocol specific ioctls */
705 	default:
706 		return (ENOTTY);		/* XXX */
707 	}
708 	return (0);
709 }
710