xref: /dragonfly/sys/netgraph/socket/ng_socket.c (revision fb5b3747)
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  * $Whistle: ng_socket.c,v 1.28 1999/11/01 09:24:52 julian Exp $
41  */
42 
43 /*
44  * Netgraph socket nodes
45  *
46  * There are two types of netgraph sockets, control and data.
47  * Control sockets have a netgraph node, but data sockets are
48  * parasitic on control sockets, and have no node of their own.
49  */
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/proc.h>
54 #include <sys/priv.h>
55 #include <sys/domain.h>
56 #include <sys/errno.h>
57 #include <sys/kernel.h>
58 #include <sys/filedesc.h>
59 #include <sys/malloc.h>
60 #include <sys/queue.h>
61 #include <sys/mbuf.h>
62 #include <sys/protosw.h>
63 #include <sys/socket.h>
64 #include <sys/socketvar.h>
65 #include <sys/sysctl.h>
66 #ifdef NOTYET
67 #include <sys/vnode.h>
68 #endif
69 
70 #include <sys/thread2.h>
71 #include <sys/socketvar2.h>
72 #include <sys/msgport2.h>
73 
74 #include <netgraph/ng_message.h>
75 #include <netgraph/netgraph.h>
76 #include "ng_socketvar.h"
77 #include "ng_socket.h"
78 
79 /*
80  * It's Ascii-art time!
81  *   +-------------+   +-------------+
82  *   |socket  (ctl)|   |socket (data)|
83  *   +-------------+   +-------------+
84  *          ^                 ^
85  *          |                 |
86  *          v                 v
87  *    +-----------+     +-----------+
88  *    |pcb   (ctl)|     |pcb  (data)|
89  *    +-----------+     +-----------+
90  *          ^                 ^
91  *          |                 |
92  *          v                 v
93  *      +--------------------------+
94  *      |   Socket type private    |
95  *      |       data               |
96  *      +--------------------------+
97  *                   ^
98  *                   |
99  *                   v
100  *           +----------------+
101  *           | struct ng_node |
102  *           +----------------+
103  */
104 
105 /* Netgraph node methods */
106 static ng_constructor_t	ngs_constructor;
107 static ng_rcvmsg_t	ngs_rcvmsg;
108 static ng_shutdown_t	ngs_rmnode;
109 static ng_newhook_t	ngs_newhook;
110 static ng_rcvdata_t	ngs_rcvdata;
111 static ng_disconnect_t	ngs_disconnect;
112 
113 /* Internal methods */
114 static int	ng_attach_data(struct socket *so);
115 static int	ng_attach_cntl(struct socket *so);
116 static int	ng_attach_common(struct socket *so, int type);
117 static void	ng_detach_common(struct ngpcb *pcbp, int type);
118 /*static int	ng_internalize(struct mbuf *m, struct thread *td); */
119 
120 static int	ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp);
121 static int	ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp);
122 static int	ng_bind(struct sockaddr *nam, struct ngpcb *pcbp);
123 
124 static int	ngs_mod_event(module_t mod, int event, void *data);
125 static int	ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg,
126 			struct sockaddr_ng *addr);
127 
128 /* Netgraph type descriptor */
129 static struct ng_type typestruct = {
130 	NG_VERSION,
131 	NG_SOCKET_NODE_TYPE,
132 	ngs_mod_event,
133 	ngs_constructor,
134 	ngs_rcvmsg,
135 	ngs_rmnode,
136 	ngs_newhook,
137 	NULL,
138 	NULL,
139 	ngs_rcvdata,
140 	ngs_rcvdata,
141 	ngs_disconnect,
142 	NULL
143 };
144 NETGRAPH_INIT(socket, &typestruct);
145 
146 /* Buffer space */
147 static u_long ngpdg_sendspace = 20 * 1024;	/* really max datagram size */
148 static u_long ngpdg_recvspace = 20 * 1024;
149 
150 /* List of all sockets */
151 LIST_HEAD(, ngpcb) ngsocklist;
152 
153 #define sotongpcb(so) ((struct ngpcb *)(so)->so_pcb)
154 
155 /* If getting unexplained errors returned, set this to "Debugger("X"); */
156 #ifndef TRAP_ERROR
157 #define TRAP_ERROR
158 #endif
159 
160 /***************************************************************
161 	Control sockets
162 ***************************************************************/
163 
164 static void
165 ngc_attach(netmsg_t msg)
166 {
167 	struct socket *so = msg->attach.base.nm_so;
168 	struct pru_attach_info *ai = msg->attach.nm_ai;
169 	struct ngpcb *const pcbp = sotongpcb(so);
170 	int error;
171 
172 	if (priv_check_cred(ai->p_ucred, PRIV_ROOT, NULL_CRED_OKAY) != 0)
173 		error = EPERM;
174 	else if (pcbp != NULL)
175 		error = EISCONN;
176 	else
177 		error = ng_attach_cntl(so);
178 	lwkt_replymsg(&msg->attach.base.lmsg, error);
179 }
180 
181 static void
182 ngc_detach(netmsg_t msg)
183 {
184 	struct socket *so = msg->detach.base.nm_so;
185 	struct ngpcb *const pcbp = sotongpcb(so);
186 	int error;
187 
188 	if (pcbp) {
189 		ng_detach_common(pcbp, NG_CONTROL);
190 		error = 0;
191 	} else {
192 		error = EINVAL;
193 	}
194 	lwkt_replymsg(&msg->detach.base.lmsg, error);
195 }
196 
197 static void
198 ngc_send(netmsg_t msg)
199 {
200 	struct socket *so = msg->send.base.nm_so;
201 	struct mbuf *m = msg->send.nm_m;
202 	struct sockaddr *addr = msg->send.nm_addr;
203 	struct mbuf *control = msg->send.nm_control;
204 	struct ngpcb *const pcbp = sotongpcb(so);
205 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
206 	struct ng_mesg *resp;
207 	struct mbuf *m0;
208 	char *xmsg, *path = NULL;
209 	int len;
210 	int error = 0;
211 
212 	if (pcbp == NULL) {
213 		error = EINVAL;
214 		goto release;
215 	}
216 #ifdef	NOTYET
217 	if (control && (error = ng_internalize(control, p))) {
218 		if (pcbp->sockdata == NULL) {
219 			error = ENOTCONN;
220 			goto release;
221 		}
222 	}
223 #else	/* NOTYET */
224 	if (control) {
225 		error = EINVAL;
226 		goto release;
227 	}
228 #endif	/* NOTYET */
229 
230 	/* Require destination as there may be >= 1 hooks on this node */
231 	if (addr == NULL) {
232 		error = EDESTADDRREQ;
233 		goto release;
234 	}
235 
236 	/* Allocate an expendable buffer for the path, chop off
237 	 * the sockaddr header, and make sure it's NUL terminated */
238 	len = sap->sg_len - 2;
239 	MALLOC(path, char *, len + 1, M_NETGRAPH, M_WAITOK);
240 	bcopy(sap->sg_data, path, len);
241 	path[len] = '\0';
242 
243 	/* Move the actual message out of mbufs into a linear buffer.
244 	 * Start by adding up the size of the data. (could use mh_len?) */
245 	for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
246 		len += m0->m_len;
247 
248 	/* Move the data into a linear buffer as well. Messages are not
249 	 * delivered in mbufs. */
250 	MALLOC(xmsg, char *, len + 1, M_NETGRAPH, M_WAITOK);
251 	m_copydata(m, 0, len, xmsg);
252 
253 	/* The callee will free the xmsg when done. The addr is our business. */
254 	error = ng_send_msg(pcbp->sockdata->node,
255 			    (struct ng_mesg *) xmsg, path, &resp);
256 
257 	/* If the callee responded with a synchronous response, then put it
258 	 * back on the receive side of the socket; sap is source address. */
259 	if (error == 0 && resp != NULL)
260 		error = ship_msg(pcbp, resp, sap);
261 
262 release:
263 	if (path != NULL)
264 		FREE(path, M_NETGRAPH);
265 	if (control != NULL)
266 		m_freem(control);
267 	if (m != NULL)
268 		m_freem(m);
269 	lwkt_replymsg(&msg->send.base.lmsg, error);
270 }
271 
272 static void
273 ngc_bind(netmsg_t msg)
274 {
275 	struct socket *so = msg->bind.base.nm_so;
276 	struct sockaddr *nam = msg->bind.nm_nam;
277 	struct ngpcb *const pcbp = sotongpcb(so);
278 	int error;
279 
280 	if (pcbp)
281 		error = ng_bind(nam, pcbp);
282 	else
283 		error = EINVAL;
284 	lwkt_replymsg(&msg->bind.base.lmsg, error);
285 }
286 
287 static void
288 ngc_connect(netmsg_t msg)
289 {
290 	struct socket *so = msg->connect.base.nm_so;
291 	struct sockaddr *nam = msg->connect.nm_nam;
292 	struct ngpcb *const pcbp = sotongpcb(so);
293 	int error;
294 
295 	if (pcbp)
296 		error = ng_connect_cntl(nam, pcbp);
297 	else
298 		error = EINVAL;
299 	lwkt_replymsg(&msg->connect.base.lmsg, error);
300 }
301 
302 /***************************************************************
303 	Data sockets
304 ***************************************************************/
305 
306 static void
307 ngd_attach(netmsg_t msg)
308 {
309 	struct socket *so = msg->attach.base.nm_so;
310 	struct ngpcb *const pcbp = sotongpcb(so);
311 	int error;
312 
313 	if (pcbp)
314 		error = EISCONN;
315 	else
316 		error = ng_attach_data(so);
317 	lwkt_replymsg(&msg->connect.base.lmsg, error);
318 }
319 
320 static void
321 ngd_detach(netmsg_t msg)
322 {
323 	struct socket *so = msg->detach.base.nm_so;
324 	struct ngpcb *const pcbp = sotongpcb(so);
325 	int error;
326 
327 	if (pcbp) {
328 		ng_detach_common(pcbp, NG_DATA);
329 		error = 0;
330 	} else {
331 		error = EINVAL;
332 	}
333 	lwkt_replymsg(&msg->detach.base.lmsg, error);
334 }
335 
336 static void
337 ngd_send(netmsg_t msg)
338 {
339 	struct socket *so = msg->send.base.nm_so;
340 	struct mbuf *m = msg->send.nm_m;
341 	struct sockaddr *addr = msg->send.nm_addr;
342 	struct mbuf *control = msg->send.nm_control;
343 	struct ngpcb *const pcbp = sotongpcb(so);
344 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
345 	meta_p  mp = NULL;
346 	int     len, error;
347 	hook_p  hook = NULL;
348 	char	hookname[NG_HOOKSIZ];
349 
350 	if ((pcbp == NULL) || (control != NULL)) {
351 		error = EINVAL;
352 		goto release;
353 	}
354 	if (pcbp->sockdata == NULL) {
355 		error = ENOTCONN;
356 		goto release;
357 	}
358 	/*
359 	 * If the user used any of these ways to not specify an address
360 	 * then handle specially.
361 	 */
362 	if ((sap == NULL)
363 	    || ((len = sap->sg_len - 2) <= 0)
364 	    || (*sap->sg_data == '\0')) {
365 		if (pcbp->sockdata->node->numhooks != 1) {
366 			error = EDESTADDRREQ;
367 			goto release;
368 		}
369 		/*
370 		 * if exactly one hook exists, just use it.
371 		 * Special case to allow write(2) to work on an ng_socket.
372 		 */
373 		hook = LIST_FIRST(&pcbp->sockdata->node->hooks);
374 	} else {
375 		if (len >= NG_HOOKSIZ) {
376 			error = EINVAL;
377 			goto release;
378 		}
379 
380 		/*
381 		 * chop off the sockaddr header, and make sure it's NUL
382 		 * terminated
383 		 */
384 		bcopy(sap->sg_data, hookname, len);
385 		hookname[len] = '\0';
386 
387 		/* Find the correct hook from 'hookname' */
388 		LIST_FOREACH(hook, &pcbp->sockdata->node->hooks, hooks) {
389 			if (strcmp(hookname, hook->name) == 0)
390 				break;
391 		}
392 		if (hook == NULL)
393 			error = EHOSTUNREACH;
394 	}
395 
396 	/* Send data (OK if hook is NULL) */
397 	NG_SEND_DATA(error, hook, m, mp);	/* makes m NULL */
398 
399 release:
400 	if (control != NULL)
401 		m_freem(control);
402 	if (m != NULL)
403 		m_freem(m);
404 	lwkt_replymsg(&msg->send.base.lmsg, error);
405 }
406 
407 static void
408 ngd_connect(netmsg_t msg)
409 {
410 	struct socket *so = msg->connect.base.nm_so;
411 	struct sockaddr *nam = msg->connect.nm_nam;
412 	struct ngpcb *const pcbp = sotongpcb(so);
413 	int error;
414 
415 	if (pcbp) {
416 		error = ng_connect_data(nam, pcbp);
417 	} else {
418 		error = EINVAL;
419 	}
420 	lwkt_replymsg(&msg->connect.base.lmsg, error);
421 }
422 
423 /*
424  * Used for both data and control sockets
425  */
426 static void
427 ng_setsockaddr(netmsg_t msg)
428 {
429 	struct socket *so = msg->sockaddr.base.nm_so;
430 	struct sockaddr **addr = msg->sockaddr.nm_nam;
431 	struct ngpcb *pcbp;
432 	struct sockaddr_ng *sg;
433 	int sg_len, namelen;
434 	int error;
435 
436 	/* Why isn't sg_data a `char[1]' ? :-( */
437 	sg_len = sizeof(struct sockaddr_ng) - sizeof(sg->sg_data) + 1;
438 
439 	crit_enter();
440 	pcbp = sotongpcb(so);
441 	if ((pcbp == 0) || (pcbp->sockdata == NULL)) {
442 		crit_exit();
443 		error = EINVAL;
444 		goto out;
445 	}
446 
447 	namelen = 0;		/* silence compiler ! */
448 
449 	if (pcbp->sockdata->node->name != NULL)
450 		sg_len += namelen = strlen(pcbp->sockdata->node->name);
451 
452 	MALLOC(sg, struct sockaddr_ng *, sg_len, M_SONAME, M_WAITOK | M_ZERO);
453 
454 	if (pcbp->sockdata->node->name != NULL)
455 		bcopy(pcbp->sockdata->node->name, sg->sg_data, namelen);
456 	crit_exit();
457 
458 	sg->sg_len = sg_len;
459 	sg->sg_family = AF_NETGRAPH;
460 	*addr = (struct sockaddr *)sg;
461 	error = 0;
462 out:
463 	lwkt_replymsg(&msg->sockaddr.base.lmsg, error);
464 }
465 
466 /*
467  * Attach a socket to it's protocol specific partner.
468  * For a control socket, actually create a netgraph node and attach
469  * to it as well.
470  */
471 
472 static int
473 ng_attach_cntl(struct socket *so)
474 {
475 	struct ngsock *privdata;
476 	struct ngpcb *pcbp;
477 	int error;
478 
479 	/* Setup protocol control block */
480 	if ((error = ng_attach_common(so, NG_CONTROL)) != 0)
481 		return (error);
482 	pcbp = sotongpcb(so);
483 
484 	/* Allocate node private info */
485 	MALLOC(privdata, struct ngsock *,
486 	    sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO);
487 
488 	/* Make the generic node components */
489 	if ((error = ng_make_node_common(&typestruct, &privdata->node)) != 0) {
490 		FREE(privdata, M_NETGRAPH);
491 		ng_detach_common(pcbp, NG_CONTROL);
492 		return (error);
493 	}
494 	privdata->node->private = privdata;
495 
496 	/* Link the pcb and the node private data */
497 	privdata->ctlsock = pcbp;
498 	pcbp->sockdata = privdata;
499 	privdata->refs++;
500 	return (0);
501 }
502 
503 static int
504 ng_attach_data(struct socket *so)
505 {
506 	return(ng_attach_common(so, NG_DATA));
507 }
508 
509 /*
510  * Set up a socket protocol control block.
511  * This code is shared between control and data sockets.
512  */
513 static int
514 ng_attach_common(struct socket *so, int type)
515 {
516 	struct ngpcb *pcbp;
517 	int error;
518 
519 	/* Standard socket setup stuff */
520 	error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace, NULL);
521 	if (error)
522 		return (error);
523 
524 	/* Allocate the pcb */
525 	MALLOC(pcbp, struct ngpcb *, sizeof(*pcbp), M_PCB, M_WAITOK | M_ZERO);
526 	pcbp->type = type;
527 
528 	/* Link the pcb and the socket */
529 	soreference(so);
530 	so->so_pcb = (caddr_t) pcbp;
531 	pcbp->ng_socket = so;
532 
533 	/* Add the socket to linked list */
534 	LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
535 	return (0);
536 }
537 
538 /*
539  * Disassociate the socket from it's protocol specific
540  * partner. If it's attached to a node's private data structure,
541  * then unlink from that too. If we were the last socket attached to it,
542  * then shut down the entire node. Shared code for control and data sockets.
543  */
544 static void
545 ng_detach_common(struct ngpcb *pcbp, int which)
546 {
547 	struct ngsock *sockdata;
548 	struct socket *so;
549 
550 	if (pcbp->sockdata) {
551 		sockdata = pcbp->sockdata;
552 		pcbp->sockdata = NULL;
553 		switch (which) {
554 		case NG_CONTROL:
555 			sockdata->ctlsock = NULL;
556 			break;
557 		case NG_DATA:
558 			sockdata->datasock = NULL;
559 			break;
560 		default:
561 			panic(__func__);
562 		}
563 		if ((--sockdata->refs == 0) && (sockdata->node != NULL))
564 			ng_rmnode(sockdata->node);
565 	}
566 	so = pcbp->ng_socket;
567 	so->so_pcb = NULL;
568 	pcbp->ng_socket = NULL;
569 	sofree(so);		/* remove pcb ref */
570 
571 	LIST_REMOVE(pcbp, socks);
572 	FREE(pcbp, M_PCB);
573 }
574 
575 #ifdef NOTYET
576 /*
577  * File descriptors can be passed into a AF_NETGRAPH socket.
578  * Note, that file descriptors cannot be passed OUT.
579  * Only character device descriptors are accepted.
580  * Character devices are useful to connect a graph to a device,
581  * which after all is the purpose of this whole system.
582  */
583 static int
584 ng_internalize(struct mbuf *control, struct thread *td)
585 {
586 	struct filedesc *fdp = p->p_fd;
587 	const struct cmsghdr *cm = mtod(control, const struct cmsghdr *);
588 	struct file *fp;
589 	struct vnode *vn;
590 	int oldfds;
591 	int fd;
592 
593 	if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET ||
594 	    cm->cmsg_len != control->m_len) {
595 		TRAP_ERROR;
596 		return (EINVAL);
597 	}
598 
599 	/* Check there is only one FD. XXX what would more than one signify? */
600 	oldfds = (cm->cmsg_len - sizeof(*cm)) / sizeof(int);
601 	if (oldfds != 1) {
602 		TRAP_ERROR;
603 		return (EINVAL);
604 	}
605 
606 	/* Check that the FD given is legit. and change it to a pointer to a
607 	 * struct file. */
608 	fd = *(int *) (cm + 1);
609 	if ((unsigned) fd >= fdp->fd_nfiles
610 	    || (fp = fdp->fd_files[fd].fp) == NULL) {
611 		return (EBADF);
612 	}
613 
614 	/* Depending on what kind of resource it is, act differently. For
615 	 * devices, we treat it as a file. For a AF_NETGRAPH socket,
616 	 * shortcut straight to the node. */
617 	switch (fp->f_type) {
618 	case DTYPE_VNODE:
619 		vn = (struct vnode *) fp->f_data;
620 		if (vn && (vn->v_type == VCHR)) {
621 			/* for a VCHR, actually reference the FILE */
622 			fp->f_count++;
623 			/* XXX then what :) */
624 			/* how to pass on to other modules? */
625 		} else {
626 			TRAP_ERROR;
627 			return (EINVAL);
628 		}
629 		break;
630 	default:
631 		TRAP_ERROR;
632 		return (EINVAL);
633 	}
634 	return (0);
635 }
636 #endif	/* NOTYET */
637 
638 /*
639  * Connect the data socket to a named control socket node.
640  */
641 static int
642 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
643 {
644 	struct sockaddr_ng *sap;
645 	node_p farnode;
646 	struct ngsock *sockdata;
647 	int error;
648 
649 	/* If we are already connected, don't do it again */
650 	if (pcbp->sockdata != NULL)
651 		return (EISCONN);
652 
653 	/* Find the target (victim) and check it doesn't already have a data
654 	 * socket. Also check it is a 'socket' type node. */
655 	sap = (struct sockaddr_ng *) nam;
656 	if ((error = ng_path2node(NULL, sap->sg_data, &farnode, NULL)))
657 		return (error);
658 
659 	if (strcmp(farnode->type->name, NG_SOCKET_NODE_TYPE) != 0)
660 		return (EINVAL);
661 	sockdata = farnode->private;
662 	if (sockdata->datasock != NULL)
663 		return (EADDRINUSE);
664 
665 	/* Link the PCB and the private data struct. and note the extra
666 	 * reference */
667 	sockdata->datasock = pcbp;
668 	pcbp->sockdata = sockdata;
669 	sockdata->refs++;
670 	return (0);
671 }
672 
673 /*
674  * Connect the existing control socket node to a named node:hook.
675  * The hook we use on this end is the same name as the remote node name.
676  */
677 static int
678 ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp)
679 {
680 	struct ngsock *const sockdata = pcbp->sockdata;
681 	struct sockaddr_ng *sap;
682 	char *node, *hook;
683 	node_p farnode;
684 	int rtn, error;
685 
686 	sap = (struct sockaddr_ng *) nam;
687 	rtn = ng_path_parse(sap->sg_data, &node, NULL, &hook);
688 	if (rtn < 0 || node == NULL || hook == NULL) {
689 		TRAP_ERROR;
690 		return (EINVAL);
691 	}
692 	farnode = ng_findname(sockdata->node, node);
693 	if (farnode == NULL) {
694 		TRAP_ERROR;
695 		return (EADDRNOTAVAIL);
696 	}
697 
698 	/* Connect, using a hook name the same as the far node name. */
699 	error = ng_con_nodes(sockdata->node, node, farnode, hook);
700 	return error;
701 }
702 
703 /*
704  * Binding a socket means giving the corresponding node a name
705  */
706 static int
707 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
708 {
709 	struct ngsock *const sockdata = pcbp->sockdata;
710 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
711 
712 	if (sockdata == NULL) {
713 		TRAP_ERROR;
714 		return (EINVAL);
715 	}
716 	if (sap->sg_len < 3 || sap->sg_data[sap->sg_len - 3] != '\0') {
717 		TRAP_ERROR;
718 		return (EINVAL);
719 	}
720 	return (ng_name_node(sockdata->node, sap->sg_data));
721 }
722 
723 /*
724  * Take a message and pass it up to the control socket associated
725  * with the node.
726  */
727 static int
728 ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg, struct sockaddr_ng *addr)
729 {
730 	struct socket *const so = pcbp->ng_socket;
731 	struct mbuf *mdata;
732 	int msglen;
733 
734 	/* Copy the message itself into an mbuf chain */
735 	msglen = sizeof(struct ng_mesg) + msg->header.arglen;
736 	mdata = m_devget((caddr_t) msg, msglen, 0, NULL, NULL);
737 
738 	/* Here we free the message, as we are the end of the line.
739 	 * We need to do that regardless of whether we got mbufs. */
740 	FREE(msg, M_NETGRAPH);
741 
742 	if (mdata == NULL) {
743 		TRAP_ERROR;
744 		return (ENOBUFS);
745 	}
746 
747 	/* Send it up to the socket */
748 	lwkt_gettoken(&so->so_rcv.ssb_token);
749 	if (ssb_appendaddr(&so->so_rcv,
750 	    (struct sockaddr *) addr, mdata, NULL) == 0) {
751 		lwkt_reltoken(&so->so_rcv.ssb_token);
752 		TRAP_ERROR;
753 		m_freem(mdata);
754 		return (ENOBUFS);
755 	}
756 	sorwakeup(so);
757 	lwkt_reltoken(&so->so_rcv.ssb_token);
758 	return (0);
759 }
760 
761 /*
762  * You can only create new nodes from the socket end of things.
763  */
764 static int
765 ngs_constructor(node_p *nodep)
766 {
767 	return (EINVAL);
768 }
769 
770 /*
771  * We allow any hook to be connected to the node.
772  * There is no per-hook private information though.
773  */
774 static int
775 ngs_newhook(node_p node, hook_p hook, const char *name)
776 {
777 	hook->private = node->private;
778 	return (0);
779 }
780 
781 /*
782  * Incoming messages get passed up to the control socket.
783  * Unless they are for us specifically (socket_type)
784  */
785 static int
786 ngs_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
787 	   struct ng_mesg **resp)
788 {
789 	struct ngsock *const sockdata = node->private;
790 	struct ngpcb *const pcbp = sockdata->ctlsock;
791 	struct sockaddr_ng *addr;
792 	int addrlen;
793 	int error = 0;
794 
795 	/* Only allow mesgs to be passed if we have the control socket.
796 	 * Data sockets can only support the generic messages. */
797 	if (pcbp == NULL) {
798 		TRAP_ERROR;
799 		return (EINVAL);
800 	}
801 
802 	if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
803 		switch (msg->header.cmd) {
804 		case NGM_SOCK_CMD_NOLINGER:
805 			sockdata->flags |= NGS_FLAG_NOLINGER;
806 			break;
807 		case NGM_SOCK_CMD_LINGER:
808 			sockdata->flags &= ~NGS_FLAG_NOLINGER;
809 			break;
810 		default:
811 			error = EINVAL;		/* unknown command */
812 		}
813 		/* Free the message and return */
814 		FREE(msg, M_NETGRAPH);
815 		return(error);
816 
817 	}
818 	/* Get the return address into a sockaddr */
819 	if ((retaddr == NULL) || (*retaddr == '\0'))
820 		retaddr = "";
821 	addrlen = strlen(retaddr);
822 	MALLOC(addr, struct sockaddr_ng *, addrlen + 4, M_NETGRAPH, M_NOWAIT);
823 	if (addr == NULL) {
824 		TRAP_ERROR;
825 		return (ENOMEM);
826 	}
827 	addr->sg_len = addrlen + 3;
828 	addr->sg_family = AF_NETGRAPH;
829 	bcopy(retaddr, addr->sg_data, addrlen);
830 	addr->sg_data[addrlen] = '\0';
831 
832 	/* Send it up */
833 	error = ship_msg(pcbp, msg, addr);
834 	FREE(addr, M_NETGRAPH);
835 	return (error);
836 }
837 
838 /*
839  * Receive data on a hook
840  */
841 static int
842 ngs_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
843 {
844 	struct ngsock *const sockdata = hook->node->private;
845 	struct ngpcb *const pcbp = sockdata->datasock;
846 	struct socket *so;
847 	struct sockaddr_ng *addr;
848 	char *addrbuf[NG_HOOKSIZ + 4];
849 	int addrlen;
850 
851 	/* If there is no data socket, black-hole it */
852 	if (pcbp == NULL) {
853 		NG_FREE_DATA(m, meta);
854 		return (0);
855 	}
856 	so = pcbp->ng_socket;
857 
858 	/* Get the return address into a sockaddr. */
859 	addrlen = strlen(hook->name);	/* <= NG_HOOKSIZ - 1 */
860 	addr = (struct sockaddr_ng *) addrbuf;
861 	addr->sg_len = addrlen + 3;
862 	addr->sg_family = AF_NETGRAPH;
863 	bcopy(hook->name, addr->sg_data, addrlen);
864 	addr->sg_data[addrlen] = '\0';
865 
866 	/* We have no use for the meta data, free/clear it now. */
867 	NG_FREE_META(meta);
868 
869 	/* Try to tell the socket which hook it came in on */
870 	lwkt_gettoken(&so->so_rcv.ssb_token);
871 	if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *) addr, m, NULL) == 0) {
872 		lwkt_reltoken(&so->so_rcv.ssb_token);
873 		m_freem(m);
874 		TRAP_ERROR;
875 		return (ENOBUFS);
876 	}
877 	sorwakeup(so);
878 	lwkt_reltoken(&so->so_rcv.ssb_token);
879 	return (0);
880 }
881 
882 /*
883  * Hook disconnection
884  *
885  * For this type, removal of the last link destroys the node
886  * if the NOLINGER flag is set.
887  */
888 static int
889 ngs_disconnect(hook_p hook)
890 {
891 	struct ngsock *const sockdata = hook->node->private;
892 
893 	if ((sockdata->flags & NGS_FLAG_NOLINGER )
894 	    && (hook->node->numhooks == 0)) {
895 		ng_rmnode(hook->node);
896 	}
897 	return (0);
898 }
899 
900 /*
901  * Do local shutdown processing.
902  * In this case, that involves making sure the socket
903  * knows we should be shutting down.
904  */
905 static int
906 ngs_rmnode(node_p node)
907 {
908 	struct ngsock *const sockdata = node->private;
909 	struct ngpcb *const dpcbp = sockdata->datasock;
910 	struct ngpcb *const pcbp = sockdata->ctlsock;
911 
912 	ng_cutlinks(node);
913 	ng_unname(node);
914 
915 	if (dpcbp != NULL) {
916 		soisdisconnected(dpcbp->ng_socket);
917 		dpcbp->sockdata = NULL;
918 		sockdata->datasock = NULL;
919 		sockdata->refs--;
920 	}
921 	if (pcbp != NULL) {
922 		soisdisconnected(pcbp->ng_socket);
923 		pcbp->sockdata = NULL;
924 		sockdata->ctlsock = NULL;
925 		sockdata->refs--;
926 	}
927 	node->private = NULL;
928 	ng_unref(node);
929 	FREE(sockdata, M_NETGRAPH);
930 	return (0);
931 }
932 
933 /*
934  * Control and data socket type descriptors
935  */
936 
937 static struct pr_usrreqs ngc_usrreqs = {
938 	.pru_abort = NULL,
939 	.pru_accept = pr_generic_notsupp,
940 	.pru_attach = ngc_attach,
941 	.pru_bind = ngc_bind,
942 	.pru_connect = ngc_connect,
943 	.pru_connect2 = pr_generic_notsupp,
944 	.pru_control = pr_generic_notsupp,
945 	.pru_detach = ngc_detach,
946 	.pru_disconnect = NULL,
947 	.pru_listen = pr_generic_notsupp,
948 	.pru_peeraddr = NULL,
949 	.pru_rcvd = pr_generic_notsupp,
950 	.pru_rcvoob = pr_generic_notsupp,
951 	.pru_send = ngc_send,
952 	.pru_sense = pru_sense_null,
953 	.pru_shutdown = NULL,
954 	.pru_sockaddr = ng_setsockaddr,
955 	.pru_sosend = sosend,
956 	.pru_soreceive = soreceive
957 };
958 
959 static struct pr_usrreqs ngd_usrreqs = {
960 	.pru_abort = NULL,
961 	.pru_accept = pr_generic_notsupp,
962 	.pru_attach = ngd_attach,
963 	.pru_bind = NULL,
964 	.pru_connect = ngd_connect,
965 	.pru_connect2 = pr_generic_notsupp,
966 	.pru_control = pr_generic_notsupp,
967 	.pru_detach = ngd_detach,
968 	.pru_disconnect = NULL,
969 	.pru_listen = pr_generic_notsupp,
970 	.pru_peeraddr = NULL,
971 	.pru_rcvd = pr_generic_notsupp,
972 	.pru_rcvoob = pr_generic_notsupp,
973 	.pru_send = ngd_send,
974 	.pru_sense = pru_sense_null,
975 	.pru_shutdown = NULL,
976 	.pru_sockaddr = ng_setsockaddr,
977 	.pru_sosend = sosend,
978 	.pru_soreceive = soreceive
979 };
980 
981 /*
982  * Definitions of protocols supported in the NETGRAPH domain.
983  */
984 
985 extern struct domain ngdomain;		/* stop compiler warnings */
986 
987 static struct protosw ngsw[] = {
988     {
989 	.pr_type = SOCK_DGRAM,
990 	.pr_domain = &ngdomain,
991 	.pr_protocol = NG_CONTROL,
992 	.pr_flags = PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
993 	.pr_usrreqs = &ngc_usrreqs
994     },
995     {
996 	.pr_type = SOCK_DGRAM,
997 	.pr_domain = &ngdomain,
998 	.pr_protocol = NG_DATA,
999 	.pr_flags = PR_ATOMIC | PR_ADDR,
1000 	.pr_usrreqs = &ngd_usrreqs
1001     }
1002 };
1003 
1004 struct domain ngdomain = {
1005 	AF_NETGRAPH, "netgraph", NULL, NULL, NULL,
1006 	ngsw, &ngsw[NELEM(ngsw)],
1007 };
1008 
1009 /*
1010  * Handle loading and unloading for this node type
1011  * This is to handle auxiliary linkages (e.g protocol domain addition).
1012  */
1013 static int
1014 ngs_mod_event(module_t mod, int event, void *data)
1015 {
1016 	int error = 0;
1017 
1018 	switch (event) {
1019 	case MOD_LOAD:
1020 		/* Register protocol domain */
1021 		net_add_domain(&ngdomain);
1022 		break;
1023 	case MOD_UNLOAD:
1024 		/* Insure there are no open netgraph sockets */
1025 		if (!LIST_EMPTY(&ngsocklist)) {
1026 			error = EBUSY;
1027 			break;
1028 		}
1029 
1030 #ifdef NOTYET
1031 		/* Unregister protocol domain XXX can't do this yet.. */
1032 		if ((error = net_rm_domain(&ngdomain)) != 0)
1033 			break;
1034 #else
1035 		error = EBUSY;
1036 #endif
1037 		break;
1038 	default:
1039 		error = EOPNOTSUPP;
1040 		break;
1041 	}
1042 	return (error);
1043 }
1044 
1045 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, 0, AF_NETGRAPH, "");
1046 SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW, 0, "DATA");
1047 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, 0, NG_DATA, "");
1048 SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW, 0, "CONTROL");
1049 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, 0, NG_CONTROL, "");
1050 
1051