xref: /dragonfly/sys/netgraph/socket/ng_socket.c (revision bcb3e04d)
1 
2 /*
3  * ng_socket.c
4  *
5  * Copyright (c) 1996-1999 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Author: Julian Elischer <julian@freebsd.org>
38  *
39  * $FreeBSD: src/sys/netgraph/ng_socket.c,v 1.11.2.6 2002/07/02 22:17:18 archie Exp $
40  * $DragonFly: src/sys/netgraph/socket/ng_socket.c,v 1.17 2008/11/01 04:22:15 sephe Exp $
41  * $Whistle: ng_socket.c,v 1.28 1999/11/01 09:24:52 julian Exp $
42  */
43 
44 /*
45  * Netgraph socket nodes
46  *
47  * There are two types of netgraph sockets, control and data.
48  * Control sockets have a netgraph node, but data sockets are
49  * parasitic on control sockets, and have no node of their own.
50  */
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/proc.h>
55 #include <sys/priv.h>
56 #include <sys/domain.h>
57 #include <sys/errno.h>
58 #include <sys/kernel.h>
59 #include <sys/filedesc.h>
60 #include <sys/malloc.h>
61 #include <sys/queue.h>
62 #include <sys/mbuf.h>
63 #include <sys/protosw.h>
64 #include <sys/socket.h>
65 #include <sys/socketvar.h>
66 #include <sys/sysctl.h>
67 #ifdef NOTYET
68 #include <sys/vnode.h>
69 #endif
70 
71 #include <sys/thread2.h>
72 #include <sys/socketvar2.h>
73 #include <sys/msgport2.h>
74 
75 #include <netgraph/ng_message.h>
76 #include <netgraph/netgraph.h>
77 #include "ng_socketvar.h"
78 #include "ng_socket.h"
79 
80 /*
81  * It's Ascii-art time!
82  *   +-------------+   +-------------+
83  *   |socket  (ctl)|   |socket (data)|
84  *   +-------------+   +-------------+
85  *          ^                 ^
86  *          |                 |
87  *          v                 v
88  *    +-----------+     +-----------+
89  *    |pcb   (ctl)|     |pcb  (data)|
90  *    +-----------+     +-----------+
91  *          ^                 ^
92  *          |                 |
93  *          v                 v
94  *      +--------------------------+
95  *      |   Socket type private    |
96  *      |       data               |
97  *      +--------------------------+
98  *                   ^
99  *                   |
100  *                   v
101  *           +----------------+
102  *           | struct ng_node |
103  *           +----------------+
104  */
105 
106 /* Netgraph node methods */
107 static ng_constructor_t	ngs_constructor;
108 static ng_rcvmsg_t	ngs_rcvmsg;
109 static ng_shutdown_t	ngs_rmnode;
110 static ng_newhook_t	ngs_newhook;
111 static ng_rcvdata_t	ngs_rcvdata;
112 static ng_disconnect_t	ngs_disconnect;
113 
114 /* Internal methods */
115 static int	ng_attach_data(struct socket *so);
116 static int	ng_attach_cntl(struct socket *so);
117 static int	ng_attach_common(struct socket *so, int type);
118 static void	ng_detach_common(struct ngpcb *pcbp, int type);
119 /*static int	ng_internalize(struct mbuf *m, struct thread *td); */
120 
121 static int	ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp);
122 static int	ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp);
123 static int	ng_bind(struct sockaddr *nam, struct ngpcb *pcbp);
124 
125 static int	ngs_mod_event(module_t mod, int event, void *data);
126 static int	ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg,
127 			struct sockaddr_ng *addr);
128 
129 /* Netgraph type descriptor */
130 static struct ng_type typestruct = {
131 	NG_VERSION,
132 	NG_SOCKET_NODE_TYPE,
133 	ngs_mod_event,
134 	ngs_constructor,
135 	ngs_rcvmsg,
136 	ngs_rmnode,
137 	ngs_newhook,
138 	NULL,
139 	NULL,
140 	ngs_rcvdata,
141 	ngs_rcvdata,
142 	ngs_disconnect,
143 	NULL
144 };
145 NETGRAPH_INIT(socket, &typestruct);
146 
147 /* Buffer space */
148 static u_long ngpdg_sendspace = 20 * 1024;	/* really max datagram size */
149 static u_long ngpdg_recvspace = 20 * 1024;
150 
151 /* List of all sockets */
152 LIST_HEAD(, ngpcb) ngsocklist;
153 
154 #define sotongpcb(so) ((struct ngpcb *)(so)->so_pcb)
155 
156 /* If getting unexplained errors returned, set this to "Debugger("X"); */
157 #ifndef TRAP_ERROR
158 #define TRAP_ERROR
159 #endif
160 
161 /***************************************************************
162 	Control sockets
163 ***************************************************************/
164 
165 static void
166 ngc_attach(netmsg_t msg)
167 {
168 	struct socket *so = msg->attach.base.nm_so;
169 	struct pru_attach_info *ai = msg->attach.nm_ai;
170 	struct ngpcb *const pcbp = sotongpcb(so);
171 	int error;
172 
173 	if (priv_check_cred(ai->p_ucred, PRIV_ROOT, NULL_CRED_OKAY) != 0)
174 		error = EPERM;
175 	else if (pcbp != NULL)
176 		error = EISCONN;
177 	else
178 		error = ng_attach_cntl(so);
179 	lwkt_replymsg(&msg->attach.base.lmsg, error);
180 }
181 
182 static void
183 ngc_detach(netmsg_t msg)
184 {
185 	struct socket *so = msg->detach.base.nm_so;
186 	struct ngpcb *const pcbp = sotongpcb(so);
187 	int error;
188 
189 	if (pcbp) {
190 		ng_detach_common(pcbp, NG_CONTROL);
191 		error = 0;
192 	} else {
193 		error = EINVAL;
194 	}
195 	lwkt_replymsg(&msg->detach.base.lmsg, error);
196 }
197 
198 static void
199 ngc_send(netmsg_t msg)
200 {
201 	struct socket *so = msg->send.base.nm_so;
202 	struct mbuf *m = msg->send.nm_m;
203 	struct sockaddr *addr = msg->send.nm_addr;
204 	struct mbuf *control = msg->send.nm_control;
205 	struct ngpcb *const pcbp = sotongpcb(so);
206 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
207 	struct ng_mesg *resp;
208 	struct mbuf *m0;
209 	char *xmsg, *path = NULL;
210 	int len;
211 	int error = 0;
212 
213 	if (pcbp == NULL) {
214 		error = EINVAL;
215 		goto release;
216 	}
217 #ifdef	NOTYET
218 	if (control && (error = ng_internalize(control, p))) {
219 		if (pcbp->sockdata == NULL) {
220 			error = ENOTCONN;
221 			goto release;
222 		}
223 	}
224 #else	/* NOTYET */
225 	if (control) {
226 		error = EINVAL;
227 		goto release;
228 	}
229 #endif	/* NOTYET */
230 
231 	/* Require destination as there may be >= 1 hooks on this node */
232 	if (addr == NULL) {
233 		error = EDESTADDRREQ;
234 		goto release;
235 	}
236 
237 	/* Allocate an expendable buffer for the path, chop off
238 	 * the sockaddr header, and make sure it's NUL terminated */
239 	len = sap->sg_len - 2;
240 	MALLOC(path, char *, len + 1, M_NETGRAPH, M_WAITOK);
241 	bcopy(sap->sg_data, path, len);
242 	path[len] = '\0';
243 
244 	/* Move the actual message out of mbufs into a linear buffer.
245 	 * Start by adding up the size of the data. (could use mh_len?) */
246 	for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
247 		len += m0->m_len;
248 
249 	/* Move the data into a linear buffer as well. Messages are not
250 	 * delivered in mbufs. */
251 	MALLOC(xmsg, char *, len + 1, M_NETGRAPH, M_WAITOK);
252 	m_copydata(m, 0, len, xmsg);
253 
254 	/* The callee will free the xmsg when done. The addr is our business. */
255 	error = ng_send_msg(pcbp->sockdata->node,
256 			    (struct ng_mesg *) xmsg, path, &resp);
257 
258 	/* If the callee responded with a synchronous response, then put it
259 	 * back on the receive side of the socket; sap is source address. */
260 	if (error == 0 && resp != NULL)
261 		error = ship_msg(pcbp, resp, sap);
262 
263 release:
264 	if (path != NULL)
265 		FREE(path, M_NETGRAPH);
266 	if (control != NULL)
267 		m_freem(control);
268 	if (m != NULL)
269 		m_freem(m);
270 	lwkt_replymsg(&msg->send.base.lmsg, error);
271 }
272 
273 static void
274 ngc_bind(netmsg_t msg)
275 {
276 	struct socket *so = msg->bind.base.nm_so;
277 	struct sockaddr *nam = msg->bind.nm_nam;
278 	struct ngpcb *const pcbp = sotongpcb(so);
279 	int error;
280 
281 	if (pcbp)
282 		error = ng_bind(nam, pcbp);
283 	else
284 		error = EINVAL;
285 	lwkt_replymsg(&msg->bind.base.lmsg, error);
286 }
287 
288 static void
289 ngc_connect(netmsg_t msg)
290 {
291 	struct socket *so = msg->connect.base.nm_so;
292 	struct sockaddr *nam = msg->connect.nm_nam;
293 	struct ngpcb *const pcbp = sotongpcb(so);
294 	int error;
295 
296 	if (pcbp)
297 		error = ng_connect_cntl(nam, pcbp);
298 	else
299 		error = EINVAL;
300 	lwkt_replymsg(&msg->connect.base.lmsg, error);
301 }
302 
303 /***************************************************************
304 	Data sockets
305 ***************************************************************/
306 
307 static void
308 ngd_attach(netmsg_t msg)
309 {
310 	struct socket *so = msg->attach.base.nm_so;
311 	struct ngpcb *const pcbp = sotongpcb(so);
312 	int error;
313 
314 	if (pcbp)
315 		error = EISCONN;
316 	else
317 		error = ng_attach_data(so);
318 	lwkt_replymsg(&msg->connect.base.lmsg, error);
319 }
320 
321 static void
322 ngd_detach(netmsg_t msg)
323 {
324 	struct socket *so = msg->detach.base.nm_so;
325 	struct ngpcb *const pcbp = sotongpcb(so);
326 	int error;
327 
328 	if (pcbp) {
329 		ng_detach_common(pcbp, NG_DATA);
330 		error = 0;
331 	} else {
332 		error = EINVAL;
333 	}
334 	lwkt_replymsg(&msg->detach.base.lmsg, error);
335 }
336 
337 static void
338 ngd_send(netmsg_t msg)
339 {
340 	struct socket *so = msg->send.base.nm_so;
341 	struct mbuf *m = msg->send.nm_m;
342 	struct sockaddr *addr = msg->send.nm_addr;
343 	struct mbuf *control = msg->send.nm_control;
344 	struct ngpcb *const pcbp = sotongpcb(so);
345 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
346 	meta_p  mp = NULL;
347 	int     len, error;
348 	hook_p  hook = NULL;
349 	char	hookname[NG_HOOKSIZ];
350 
351 	if ((pcbp == NULL) || (control != NULL)) {
352 		error = EINVAL;
353 		goto release;
354 	}
355 	if (pcbp->sockdata == NULL) {
356 		error = ENOTCONN;
357 		goto release;
358 	}
359 	/*
360 	 * If the user used any of these ways to not specify an address
361 	 * then handle specially.
362 	 */
363 	if ((sap == NULL)
364 	    || ((len = sap->sg_len - 2) <= 0)
365 	    || (*sap->sg_data == '\0')) {
366 		if (pcbp->sockdata->node->numhooks != 1) {
367 			error = EDESTADDRREQ;
368 			goto release;
369 		}
370 		/*
371 		 * if exactly one hook exists, just use it.
372 		 * Special case to allow write(2) to work on an ng_socket.
373 		 */
374 		hook = LIST_FIRST(&pcbp->sockdata->node->hooks);
375 	} else {
376 		if (len >= NG_HOOKSIZ) {
377 			error = EINVAL;
378 			goto release;
379 		}
380 
381 		/*
382 		 * chop off the sockaddr header, and make sure it's NUL
383 		 * terminated
384 		 */
385 		bcopy(sap->sg_data, hookname, len);
386 		hookname[len] = '\0';
387 
388 		/* Find the correct hook from 'hookname' */
389 		LIST_FOREACH(hook, &pcbp->sockdata->node->hooks, hooks) {
390 			if (strcmp(hookname, hook->name) == 0)
391 				break;
392 		}
393 		if (hook == NULL)
394 			error = EHOSTUNREACH;
395 	}
396 
397 	/* Send data (OK if hook is NULL) */
398 	NG_SEND_DATA(error, hook, m, mp);	/* makes m NULL */
399 
400 release:
401 	if (control != NULL)
402 		m_freem(control);
403 	if (m != NULL)
404 		m_freem(m);
405 	lwkt_replymsg(&msg->send.base.lmsg, error);
406 }
407 
408 static void
409 ngd_connect(netmsg_t msg)
410 {
411 	struct socket *so = msg->connect.base.nm_so;
412 	struct sockaddr *nam = msg->connect.nm_nam;
413 	struct ngpcb *const pcbp = sotongpcb(so);
414 	int error;
415 
416 	if (pcbp) {
417 		error = ng_connect_data(nam, pcbp);
418 	} else {
419 		error = EINVAL;
420 	}
421 	lwkt_replymsg(&msg->connect.base.lmsg, error);
422 }
423 
424 /*
425  * Used for both data and control sockets
426  */
427 static void
428 ng_setsockaddr(netmsg_t msg)
429 {
430 	struct socket *so = msg->sockaddr.base.nm_so;
431 	struct sockaddr **addr = msg->sockaddr.nm_nam;
432 	struct ngpcb *pcbp;
433 	struct sockaddr_ng *sg;
434 	int sg_len, namelen;
435 	int error;
436 
437 	/* Why isn't sg_data a `char[1]' ? :-( */
438 	sg_len = sizeof(struct sockaddr_ng) - sizeof(sg->sg_data) + 1;
439 
440 	crit_enter();
441 	pcbp = sotongpcb(so);
442 	if ((pcbp == 0) || (pcbp->sockdata == NULL)) {
443 		crit_exit();
444 		error = EINVAL;
445 		goto out;
446 	}
447 
448 	namelen = 0;		/* silence compiler ! */
449 
450 	if (pcbp->sockdata->node->name != NULL)
451 		sg_len += namelen = strlen(pcbp->sockdata->node->name);
452 
453 	MALLOC(sg, struct sockaddr_ng *, sg_len, M_SONAME, M_WAITOK | M_ZERO);
454 
455 	if (pcbp->sockdata->node->name != NULL)
456 		bcopy(pcbp->sockdata->node->name, sg->sg_data, namelen);
457 	crit_exit();
458 
459 	sg->sg_len = sg_len;
460 	sg->sg_family = AF_NETGRAPH;
461 	*addr = (struct sockaddr *)sg;
462 	error = 0;
463 out:
464 	lwkt_replymsg(&msg->sockaddr.base.lmsg, error);
465 }
466 
467 /*
468  * Attach a socket to it's protocol specific partner.
469  * For a control socket, actually create a netgraph node and attach
470  * to it as well.
471  */
472 
473 static int
474 ng_attach_cntl(struct socket *so)
475 {
476 	struct ngsock *privdata;
477 	struct ngpcb *pcbp;
478 	int error;
479 
480 	/* Setup protocol control block */
481 	if ((error = ng_attach_common(so, NG_CONTROL)) != 0)
482 		return (error);
483 	pcbp = sotongpcb(so);
484 
485 	/* Allocate node private info */
486 	MALLOC(privdata, struct ngsock *,
487 	    sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO);
488 
489 	/* Make the generic node components */
490 	if ((error = ng_make_node_common(&typestruct, &privdata->node)) != 0) {
491 		FREE(privdata, M_NETGRAPH);
492 		ng_detach_common(pcbp, NG_CONTROL);
493 		return (error);
494 	}
495 	privdata->node->private = privdata;
496 
497 	/* Link the pcb and the node private data */
498 	privdata->ctlsock = pcbp;
499 	pcbp->sockdata = privdata;
500 	privdata->refs++;
501 	return (0);
502 }
503 
504 static int
505 ng_attach_data(struct socket *so)
506 {
507 	return(ng_attach_common(so, NG_DATA));
508 }
509 
510 /*
511  * Set up a socket protocol control block.
512  * This code is shared between control and data sockets.
513  */
514 static int
515 ng_attach_common(struct socket *so, int type)
516 {
517 	struct ngpcb *pcbp;
518 	int error;
519 
520 	/* Standard socket setup stuff */
521 	error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace, NULL);
522 	if (error)
523 		return (error);
524 
525 	/* Allocate the pcb */
526 	MALLOC(pcbp, struct ngpcb *, sizeof(*pcbp), M_PCB, M_WAITOK | M_ZERO);
527 	pcbp->type = type;
528 
529 	/* Link the pcb and the socket */
530 	soreference(so);
531 	so->so_pcb = (caddr_t) pcbp;
532 	pcbp->ng_socket = so;
533 
534 	/* Add the socket to linked list */
535 	LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
536 	return (0);
537 }
538 
539 /*
540  * Disassociate the socket from it's protocol specific
541  * partner. If it's attached to a node's private data structure,
542  * then unlink from that too. If we were the last socket attached to it,
543  * then shut down the entire node. Shared code for control and data sockets.
544  */
545 static void
546 ng_detach_common(struct ngpcb *pcbp, int which)
547 {
548 	struct ngsock *sockdata;
549 	struct socket *so;
550 
551 	if (pcbp->sockdata) {
552 		sockdata = pcbp->sockdata;
553 		pcbp->sockdata = NULL;
554 		switch (which) {
555 		case NG_CONTROL:
556 			sockdata->ctlsock = NULL;
557 			break;
558 		case NG_DATA:
559 			sockdata->datasock = NULL;
560 			break;
561 		default:
562 			panic(__func__);
563 		}
564 		if ((--sockdata->refs == 0) && (sockdata->node != NULL))
565 			ng_rmnode(sockdata->node);
566 	}
567 	so = pcbp->ng_socket;
568 	so->so_pcb = NULL;
569 	pcbp->ng_socket = NULL;
570 	sofree(so);		/* remove pcb ref */
571 
572 	LIST_REMOVE(pcbp, socks);
573 	FREE(pcbp, M_PCB);
574 }
575 
576 #ifdef NOTYET
577 /*
578  * File descriptors can be passed into a AF_NETGRAPH socket.
579  * Note, that file descriptors cannot be passed OUT.
580  * Only character device descriptors are accepted.
581  * Character devices are useful to connect a graph to a device,
582  * which after all is the purpose of this whole system.
583  */
584 static int
585 ng_internalize(struct mbuf *control, struct thread *td)
586 {
587 	struct filedesc *fdp = p->p_fd;
588 	const struct cmsghdr *cm = mtod(control, const struct cmsghdr *);
589 	struct file *fp;
590 	struct vnode *vn;
591 	int oldfds;
592 	int fd;
593 
594 	if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET ||
595 	    cm->cmsg_len != control->m_len) {
596 		TRAP_ERROR;
597 		return (EINVAL);
598 	}
599 
600 	/* Check there is only one FD. XXX what would more than one signify? */
601 	oldfds = (cm->cmsg_len - sizeof(*cm)) / sizeof(int);
602 	if (oldfds != 1) {
603 		TRAP_ERROR;
604 		return (EINVAL);
605 	}
606 
607 	/* Check that the FD given is legit. and change it to a pointer to a
608 	 * struct file. */
609 	fd = *(int *) (cm + 1);
610 	if ((unsigned) fd >= fdp->fd_nfiles
611 	    || (fp = fdp->fd_files[fd].fp) == NULL) {
612 		return (EBADF);
613 	}
614 
615 	/* Depending on what kind of resource it is, act differently. For
616 	 * devices, we treat it as a file. For a AF_NETGRAPH socket,
617 	 * shortcut straight to the node. */
618 	switch (fp->f_type) {
619 	case DTYPE_VNODE:
620 		vn = (struct vnode *) fp->f_data;
621 		if (vn && (vn->v_type == VCHR)) {
622 			/* for a VCHR, actually reference the FILE */
623 			fp->f_count++;
624 			/* XXX then what :) */
625 			/* how to pass on to other modules? */
626 		} else {
627 			TRAP_ERROR;
628 			return (EINVAL);
629 		}
630 		break;
631 	default:
632 		TRAP_ERROR;
633 		return (EINVAL);
634 	}
635 	return (0);
636 }
637 #endif	/* NOTYET */
638 
639 /*
640  * Connect the data socket to a named control socket node.
641  */
642 static int
643 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
644 {
645 	struct sockaddr_ng *sap;
646 	node_p farnode;
647 	struct ngsock *sockdata;
648 	int error;
649 
650 	/* If we are already connected, don't do it again */
651 	if (pcbp->sockdata != NULL)
652 		return (EISCONN);
653 
654 	/* Find the target (victim) and check it doesn't already have a data
655 	 * socket. Also check it is a 'socket' type node. */
656 	sap = (struct sockaddr_ng *) nam;
657 	if ((error = ng_path2node(NULL, sap->sg_data, &farnode, NULL)))
658 		return (error);
659 
660 	if (strcmp(farnode->type->name, NG_SOCKET_NODE_TYPE) != 0)
661 		return (EINVAL);
662 	sockdata = farnode->private;
663 	if (sockdata->datasock != NULL)
664 		return (EADDRINUSE);
665 
666 	/* Link the PCB and the private data struct. and note the extra
667 	 * reference */
668 	sockdata->datasock = pcbp;
669 	pcbp->sockdata = sockdata;
670 	sockdata->refs++;
671 	return (0);
672 }
673 
674 /*
675  * Connect the existing control socket node to a named node:hook.
676  * The hook we use on this end is the same name as the remote node name.
677  */
678 static int
679 ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp)
680 {
681 	struct ngsock *const sockdata = pcbp->sockdata;
682 	struct sockaddr_ng *sap;
683 	char *node, *hook;
684 	node_p farnode;
685 	int rtn, error;
686 
687 	sap = (struct sockaddr_ng *) nam;
688 	rtn = ng_path_parse(sap->sg_data, &node, NULL, &hook);
689 	if (rtn < 0 || node == NULL || hook == NULL) {
690 		TRAP_ERROR;
691 		return (EINVAL);
692 	}
693 	farnode = ng_findname(sockdata->node, node);
694 	if (farnode == NULL) {
695 		TRAP_ERROR;
696 		return (EADDRNOTAVAIL);
697 	}
698 
699 	/* Connect, using a hook name the same as the far node name. */
700 	error = ng_con_nodes(sockdata->node, node, farnode, hook);
701 	return error;
702 }
703 
704 /*
705  * Binding a socket means giving the corresponding node a name
706  */
707 static int
708 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
709 {
710 	struct ngsock *const sockdata = pcbp->sockdata;
711 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
712 
713 	if (sockdata == NULL) {
714 		TRAP_ERROR;
715 		return (EINVAL);
716 	}
717 	if (sap->sg_len < 3 || sap->sg_data[sap->sg_len - 3] != '\0') {
718 		TRAP_ERROR;
719 		return (EINVAL);
720 	}
721 	return (ng_name_node(sockdata->node, sap->sg_data));
722 }
723 
724 /*
725  * Take a message and pass it up to the control socket associated
726  * with the node.
727  */
728 static int
729 ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg, struct sockaddr_ng *addr)
730 {
731 	struct socket *const so = pcbp->ng_socket;
732 	struct mbuf *mdata;
733 	int msglen;
734 
735 	/* Copy the message itself into an mbuf chain */
736 	msglen = sizeof(struct ng_mesg) + msg->header.arglen;
737 	mdata = m_devget((caddr_t) msg, msglen, 0, NULL, NULL);
738 
739 	/* Here we free the message, as we are the end of the line.
740 	 * We need to do that regardless of whether we got mbufs. */
741 	FREE(msg, M_NETGRAPH);
742 
743 	if (mdata == NULL) {
744 		TRAP_ERROR;
745 		return (ENOBUFS);
746 	}
747 
748 	/* Send it up to the socket */
749 	if (ssb_appendaddr(&so->so_rcv,
750 	    (struct sockaddr *) addr, mdata, NULL) == 0) {
751 		TRAP_ERROR;
752 		m_freem(mdata);
753 		return (ENOBUFS);
754 	}
755 	sorwakeup(so);
756 	return (0);
757 }
758 
759 /*
760  * You can only create new nodes from the socket end of things.
761  */
762 static int
763 ngs_constructor(node_p *nodep)
764 {
765 	return (EINVAL);
766 }
767 
768 /*
769  * We allow any hook to be connected to the node.
770  * There is no per-hook private information though.
771  */
772 static int
773 ngs_newhook(node_p node, hook_p hook, const char *name)
774 {
775 	hook->private = node->private;
776 	return (0);
777 }
778 
779 /*
780  * Incoming messages get passed up to the control socket.
781  * Unless they are for us specifically (socket_type)
782  */
783 static int
784 ngs_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
785 	   struct ng_mesg **resp)
786 {
787 	struct ngsock *const sockdata = node->private;
788 	struct ngpcb *const pcbp = sockdata->ctlsock;
789 	struct sockaddr_ng *addr;
790 	int addrlen;
791 	int error = 0;
792 
793 	/* Only allow mesgs to be passed if we have the control socket.
794 	 * Data sockets can only support the generic messages. */
795 	if (pcbp == NULL) {
796 		TRAP_ERROR;
797 		return (EINVAL);
798 	}
799 
800 	if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
801 		switch (msg->header.cmd) {
802 		case NGM_SOCK_CMD_NOLINGER:
803 			sockdata->flags |= NGS_FLAG_NOLINGER;
804 			break;
805 		case NGM_SOCK_CMD_LINGER:
806 			sockdata->flags &= ~NGS_FLAG_NOLINGER;
807 			break;
808 		default:
809 			error = EINVAL;		/* unknown command */
810 		}
811 		/* Free the message and return */
812 		FREE(msg, M_NETGRAPH);
813 		return(error);
814 
815 	}
816 	/* Get the return address into a sockaddr */
817 	if ((retaddr == NULL) || (*retaddr == '\0'))
818 		retaddr = "";
819 	addrlen = strlen(retaddr);
820 	MALLOC(addr, struct sockaddr_ng *, addrlen + 4, M_NETGRAPH, M_NOWAIT);
821 	if (addr == NULL) {
822 		TRAP_ERROR;
823 		return (ENOMEM);
824 	}
825 	addr->sg_len = addrlen + 3;
826 	addr->sg_family = AF_NETGRAPH;
827 	bcopy(retaddr, addr->sg_data, addrlen);
828 	addr->sg_data[addrlen] = '\0';
829 
830 	/* Send it up */
831 	error = ship_msg(pcbp, msg, addr);
832 	FREE(addr, M_NETGRAPH);
833 	return (error);
834 }
835 
836 /*
837  * Receive data on a hook
838  */
839 static int
840 ngs_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
841 {
842 	struct ngsock *const sockdata = hook->node->private;
843 	struct ngpcb *const pcbp = sockdata->datasock;
844 	struct socket *so;
845 	struct sockaddr_ng *addr;
846 	char *addrbuf[NG_HOOKSIZ + 4];
847 	int addrlen;
848 
849 	/* If there is no data socket, black-hole it */
850 	if (pcbp == NULL) {
851 		NG_FREE_DATA(m, meta);
852 		return (0);
853 	}
854 	so = pcbp->ng_socket;
855 
856 	/* Get the return address into a sockaddr. */
857 	addrlen = strlen(hook->name);	/* <= NG_HOOKSIZ - 1 */
858 	addr = (struct sockaddr_ng *) addrbuf;
859 	addr->sg_len = addrlen + 3;
860 	addr->sg_family = AF_NETGRAPH;
861 	bcopy(hook->name, addr->sg_data, addrlen);
862 	addr->sg_data[addrlen] = '\0';
863 
864 	/* We have no use for the meta data, free/clear it now. */
865 	NG_FREE_META(meta);
866 
867 	/* Try to tell the socket which hook it came in on */
868 	if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *) addr, m, NULL) == 0) {
869 		m_freem(m);
870 		TRAP_ERROR;
871 		return (ENOBUFS);
872 	}
873 	sorwakeup(so);
874 	return (0);
875 }
876 
877 /*
878  * Hook disconnection
879  *
880  * For this type, removal of the last link destroys the node
881  * if the NOLINGER flag is set.
882  */
883 static int
884 ngs_disconnect(hook_p hook)
885 {
886 	struct ngsock *const sockdata = hook->node->private;
887 
888 	if ((sockdata->flags & NGS_FLAG_NOLINGER )
889 	    && (hook->node->numhooks == 0)) {
890 		ng_rmnode(hook->node);
891 	}
892 	return (0);
893 }
894 
895 /*
896  * Do local shutdown processing.
897  * In this case, that involves making sure the socket
898  * knows we should be shutting down.
899  */
900 static int
901 ngs_rmnode(node_p node)
902 {
903 	struct ngsock *const sockdata = node->private;
904 	struct ngpcb *const dpcbp = sockdata->datasock;
905 	struct ngpcb *const pcbp = sockdata->ctlsock;
906 
907 	ng_cutlinks(node);
908 	ng_unname(node);
909 
910 	if (dpcbp != NULL) {
911 		soisdisconnected(dpcbp->ng_socket);
912 		dpcbp->sockdata = NULL;
913 		sockdata->datasock = NULL;
914 		sockdata->refs--;
915 	}
916 	if (pcbp != NULL) {
917 		soisdisconnected(pcbp->ng_socket);
918 		pcbp->sockdata = NULL;
919 		sockdata->ctlsock = NULL;
920 		sockdata->refs--;
921 	}
922 	node->private = NULL;
923 	ng_unref(node);
924 	FREE(sockdata, M_NETGRAPH);
925 	return (0);
926 }
927 
928 /*
929  * Control and data socket type descriptors
930  */
931 
932 static struct pr_usrreqs ngc_usrreqs = {
933 	.pru_abort = NULL,
934 	.pru_accept = pr_generic_notsupp,
935 	.pru_attach = ngc_attach,
936 	.pru_bind = ngc_bind,
937 	.pru_connect = ngc_connect,
938 	.pru_connect2 = pr_generic_notsupp,
939 	.pru_control = pr_generic_notsupp,
940 	.pru_detach = ngc_detach,
941 	.pru_disconnect = NULL,
942 	.pru_listen = pr_generic_notsupp,
943 	.pru_peeraddr = NULL,
944 	.pru_rcvd = pr_generic_notsupp,
945 	.pru_rcvoob = pr_generic_notsupp,
946 	.pru_send = ngc_send,
947 	.pru_sense = pru_sense_null,
948 	.pru_shutdown = NULL,
949 	.pru_sockaddr = ng_setsockaddr,
950 	.pru_sosend = sosend,
951 	.pru_soreceive = soreceive
952 };
953 
954 static struct pr_usrreqs ngd_usrreqs = {
955 	.pru_abort = NULL,
956 	.pru_accept = pr_generic_notsupp,
957 	.pru_attach = ngd_attach,
958 	.pru_bind = NULL,
959 	.pru_connect = ngd_connect,
960 	.pru_connect2 = pr_generic_notsupp,
961 	.pru_control = pr_generic_notsupp,
962 	.pru_detach = ngd_detach,
963 	.pru_disconnect = NULL,
964 	.pru_listen = pr_generic_notsupp,
965 	.pru_peeraddr = NULL,
966 	.pru_rcvd = pr_generic_notsupp,
967 	.pru_rcvoob = pr_generic_notsupp,
968 	.pru_send = ngd_send,
969 	.pru_sense = pru_sense_null,
970 	.pru_shutdown = NULL,
971 	.pru_sockaddr = ng_setsockaddr,
972 	.pru_sosend = sosend,
973 	.pru_soreceive = soreceive
974 };
975 
976 /*
977  * Definitions of protocols supported in the NETGRAPH domain.
978  */
979 
980 extern struct domain ngdomain;		/* stop compiler warnings */
981 
982 static struct protosw ngsw[] = {
983     {
984 	.pr_type = SOCK_DGRAM,
985 	.pr_domain = &ngdomain,
986 	.pr_protocol = NG_CONTROL,
987 	.pr_flags = PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
988 	.pr_usrreqs = &ngc_usrreqs
989     },
990     {
991 	.pr_type = SOCK_DGRAM,
992 	.pr_domain = &ngdomain,
993 	.pr_protocol = NG_DATA,
994 	.pr_flags = PR_ATOMIC | PR_ADDR,
995 	.pr_usrreqs = &ngd_usrreqs
996     }
997 };
998 
999 struct domain ngdomain = {
1000 	AF_NETGRAPH, "netgraph", NULL, NULL, NULL,
1001 	ngsw, &ngsw[sizeof(ngsw) / sizeof(ngsw[0])],
1002 };
1003 
1004 /*
1005  * Handle loading and unloading for this node type
1006  * This is to handle auxiliary linkages (e.g protocol domain addition).
1007  */
1008 static int
1009 ngs_mod_event(module_t mod, int event, void *data)
1010 {
1011 	int error = 0;
1012 
1013 	switch (event) {
1014 	case MOD_LOAD:
1015 		/* Register protocol domain */
1016 		net_add_domain(&ngdomain);
1017 		break;
1018 	case MOD_UNLOAD:
1019 		/* Insure there are no open netgraph sockets */
1020 		if (!LIST_EMPTY(&ngsocklist)) {
1021 			error = EBUSY;
1022 			break;
1023 		}
1024 
1025 #ifdef NOTYET
1026 		/* Unregister protocol domain XXX can't do this yet.. */
1027 		if ((error = net_rm_domain(&ngdomain)) != 0)
1028 			break;
1029 #else
1030 		error = EBUSY;
1031 #endif
1032 		break;
1033 	default:
1034 		error = EOPNOTSUPP;
1035 		break;
1036 	}
1037 	return (error);
1038 }
1039 
1040 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, 0, AF_NETGRAPH, "");
1041 SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW, 0, "DATA");
1042 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, 0, NG_DATA, "");
1043 SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW, 0, "CONTROL");
1044 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, 0, NG_CONTROL, "");
1045 
1046