xref: /dflybsd-src/sys/netgraph/socket/ng_socket.c (revision 93bffecadc0caefc46f12b736eab0e62c2b6f42e)
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 
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 int
165 ngc_attach(struct socket *so, int proto, struct pru_attach_info *ai)
166 {
167 	struct ngpcb *const pcbp = sotongpcb(so);
168 
169 	if (priv_check_cred(ai->p_ucred, PRIV_ROOT, NULL_CRED_OKAY) != 0)
170 		return (EPERM);
171 	if (pcbp != NULL)
172 		return (EISCONN);
173 	return (ng_attach_cntl(so));
174 }
175 
176 static int
177 ngc_detach(struct socket *so)
178 {
179 	struct ngpcb *const pcbp = sotongpcb(so);
180 
181 	if (pcbp == NULL)
182 		return (EINVAL);
183 	ng_detach_common(pcbp, NG_CONTROL);
184 	return (0);
185 }
186 
187 static int
188 ngc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
189 	 struct mbuf *control, struct thread *td)
190 {
191 	struct ngpcb *const pcbp = sotongpcb(so);
192 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
193 	struct ng_mesg *resp;
194 	struct mbuf *m0;
195 	char *msg, *path = NULL;
196 	int len, error = 0;
197 
198 	if (pcbp == NULL) {
199 		error = EINVAL;
200 		goto release;
201 	}
202 #ifdef	NOTYET
203 	if (control && (error = ng_internalize(control, p))) {
204 		if (pcbp->sockdata == NULL) {
205 			error = ENOTCONN;
206 			goto release;
207 		}
208 	}
209 #else	/* NOTYET */
210 	if (control) {
211 		error = EINVAL;
212 		goto release;
213 	}
214 #endif	/* NOTYET */
215 
216 	/* Require destination as there may be >= 1 hooks on this node */
217 	if (addr == NULL) {
218 		error = EDESTADDRREQ;
219 		goto release;
220 	}
221 
222 	/* Allocate an expendable buffer for the path, chop off
223 	 * the sockaddr header, and make sure it's NUL terminated */
224 	len = sap->sg_len - 2;
225 	MALLOC(path, char *, len + 1, M_NETGRAPH, M_WAITOK);
226 	bcopy(sap->sg_data, path, len);
227 	path[len] = '\0';
228 
229 	/* Move the actual message out of mbufs into a linear buffer.
230 	 * Start by adding up the size of the data. (could use mh_len?) */
231 	for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
232 		len += m0->m_len;
233 
234 	/* Move the data into a linear buffer as well. Messages are not
235 	 * delivered in mbufs. */
236 	MALLOC(msg, char *, len + 1, M_NETGRAPH, M_WAITOK);
237 	m_copydata(m, 0, len, msg);
238 
239 	/* The callee will free the msg when done. The addr is our business. */
240 	error = ng_send_msg(pcbp->sockdata->node,
241 			    (struct ng_mesg *) msg, path, &resp);
242 
243 	/* If the callee responded with a synchronous response, then put it
244 	 * back on the receive side of the socket; sap is source address. */
245 	if (error == 0 && resp != NULL)
246 		error = ship_msg(pcbp, resp, sap);
247 
248 release:
249 	if (path != NULL)
250 		FREE(path, M_NETGRAPH);
251 	if (control != NULL)
252 		m_freem(control);
253 	if (m != NULL)
254 		m_freem(m);
255 	return (error);
256 }
257 
258 static int
259 ngc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
260 {
261 	struct ngpcb *const pcbp = sotongpcb(so);
262 
263 	if (pcbp == 0)
264 		return (EINVAL);
265 	return (ng_bind(nam, pcbp));
266 }
267 
268 static int
269 ngc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
270 {
271 	struct ngpcb *const pcbp = sotongpcb(so);
272 
273 	if (pcbp == 0)
274 		return (EINVAL);
275 	return (ng_connect_cntl(nam, pcbp));
276 }
277 
278 /***************************************************************
279 	Data sockets
280 ***************************************************************/
281 
282 static int
283 ngd_attach(struct socket *so, int proto, struct pru_attach_info *ai)
284 {
285 	struct ngpcb *const pcbp = sotongpcb(so);
286 
287 	if (pcbp != NULL)
288 		return (EISCONN);
289 	return (ng_attach_data(so));
290 }
291 
292 static int
293 ngd_detach(struct socket *so)
294 {
295 	struct ngpcb *const pcbp = sotongpcb(so);
296 
297 	if (pcbp == NULL)
298 		return (EINVAL);
299 	ng_detach_common(pcbp, NG_DATA);
300 	return (0);
301 }
302 
303 static int
304 ngd_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
305 	 struct mbuf *control, struct thread *td)
306 {
307 	struct ngpcb *const pcbp = sotongpcb(so);
308 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
309 	meta_p  mp = NULL;
310 	int     len, error;
311 	hook_p  hook = NULL;
312 	char	hookname[NG_HOOKSIZ];
313 
314 	if ((pcbp == NULL) || (control != NULL)) {
315 		error = EINVAL;
316 		goto release;
317 	}
318 	if (pcbp->sockdata == NULL) {
319 		error = ENOTCONN;
320 		goto release;
321 	}
322 	/*
323 	 * If the user used any of these ways to not specify an address
324 	 * then handle specially.
325 	 */
326 	if ((sap == NULL)
327 	    || ((len = sap->sg_len - 2) <= 0)
328 	    || (*sap->sg_data == '\0')) {
329 		if (pcbp->sockdata->node->numhooks != 1) {
330 			error = EDESTADDRREQ;
331 			goto release;
332 		}
333 		/*
334 		 * if exactly one hook exists, just use it.
335 		 * Special case to allow write(2) to work on an ng_socket.
336 		 */
337 		hook = LIST_FIRST(&pcbp->sockdata->node->hooks);
338 	} else {
339 		if (len >= NG_HOOKSIZ) {
340 			error = EINVAL;
341 			goto release;
342 		}
343 
344 		/*
345 		 * chop off the sockaddr header, and make sure it's NUL
346 		 * terminated
347 		 */
348 		bcopy(sap->sg_data, hookname, len);
349 		hookname[len] = '\0';
350 
351 		/* Find the correct hook from 'hookname' */
352 		LIST_FOREACH(hook, &pcbp->sockdata->node->hooks, hooks) {
353 			if (strcmp(hookname, hook->name) == 0)
354 				break;
355 		}
356 		if (hook == NULL)
357 			error = EHOSTUNREACH;
358 	}
359 
360 	/* Send data (OK if hook is NULL) */
361 	NG_SEND_DATA(error, hook, m, mp);	/* makes m NULL */
362 
363 release:
364 	if (control != NULL)
365 		m_freem(control);
366 	if (m != NULL)
367 		m_freem(m);
368 	return (error);
369 }
370 
371 static int
372 ngd_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
373 {
374 	struct ngpcb *const pcbp = sotongpcb(so);
375 
376 	if (pcbp == 0)
377 		return (EINVAL);
378 	return (ng_connect_data(nam, pcbp));
379 }
380 
381 /*
382  * Used for both data and control sockets
383  */
384 static int
385 ng_setsockaddr(struct socket *so, struct sockaddr **addr)
386 {
387 	struct ngpcb *pcbp;
388 	struct sockaddr_ng *sg;
389 	int sg_len, namelen;
390 
391 	/* Why isn't sg_data a `char[1]' ? :-( */
392 	sg_len = sizeof(struct sockaddr_ng) - sizeof(sg->sg_data) + 1;
393 
394 	crit_enter();
395 	pcbp = sotongpcb(so);
396 	if ((pcbp == 0) || (pcbp->sockdata == NULL)) {
397 		crit_exit();
398 		return (EINVAL);
399 	}
400 
401 	namelen = 0;		/* silence compiler ! */
402 
403 	if (pcbp->sockdata->node->name != NULL)
404 		sg_len += namelen = strlen(pcbp->sockdata->node->name);
405 
406 	MALLOC(sg, struct sockaddr_ng *, sg_len, M_SONAME, M_WAITOK | M_ZERO);
407 
408 	if (pcbp->sockdata->node->name != NULL)
409 		bcopy(pcbp->sockdata->node->name, sg->sg_data, namelen);
410 	crit_exit();
411 
412 	sg->sg_len = sg_len;
413 	sg->sg_family = AF_NETGRAPH;
414 	*addr = (struct sockaddr *)sg;
415 
416 	return (0);
417 }
418 
419 /*
420  * Attach a socket to it's protocol specific partner.
421  * For a control socket, actually create a netgraph node and attach
422  * to it as well.
423  */
424 
425 static int
426 ng_attach_cntl(struct socket *so)
427 {
428 	struct ngsock *privdata;
429 	struct ngpcb *pcbp;
430 	int error;
431 
432 	/* Setup protocol control block */
433 	if ((error = ng_attach_common(so, NG_CONTROL)) != 0)
434 		return (error);
435 	pcbp = sotongpcb(so);
436 
437 	/* Allocate node private info */
438 	MALLOC(privdata, struct ngsock *,
439 	    sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO);
440 
441 	/* Make the generic node components */
442 	if ((error = ng_make_node_common(&typestruct, &privdata->node)) != 0) {
443 		FREE(privdata, M_NETGRAPH);
444 		ng_detach_common(pcbp, NG_CONTROL);
445 		return (error);
446 	}
447 	privdata->node->private = privdata;
448 
449 	/* Link the pcb and the node private data */
450 	privdata->ctlsock = pcbp;
451 	pcbp->sockdata = privdata;
452 	privdata->refs++;
453 	return (0);
454 }
455 
456 static int
457 ng_attach_data(struct socket *so)
458 {
459 	return(ng_attach_common(so, NG_DATA));
460 }
461 
462 /*
463  * Set up a socket protocol control block.
464  * This code is shared between control and data sockets.
465  */
466 static int
467 ng_attach_common(struct socket *so, int type)
468 {
469 	struct ngpcb *pcbp;
470 	int error;
471 
472 	/* Standard socket setup stuff */
473 	error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace, NULL);
474 	if (error)
475 		return (error);
476 
477 	/* Allocate the pcb */
478 	MALLOC(pcbp, struct ngpcb *, sizeof(*pcbp), M_PCB, M_WAITOK | M_ZERO);
479 	pcbp->type = type;
480 
481 	/* Link the pcb and the socket */
482 	soreference(so);
483 	so->so_pcb = (caddr_t) pcbp;
484 	pcbp->ng_socket = so;
485 
486 	/* Add the socket to linked list */
487 	LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
488 	return (0);
489 }
490 
491 /*
492  * Disassociate the socket from it's protocol specific
493  * partner. If it's attached to a node's private data structure,
494  * then unlink from that too. If we were the last socket attached to it,
495  * then shut down the entire node. Shared code for control and data sockets.
496  */
497 static void
498 ng_detach_common(struct ngpcb *pcbp, int which)
499 {
500 	struct ngsock *sockdata;
501 	struct socket *so;
502 
503 	if (pcbp->sockdata) {
504 		sockdata = pcbp->sockdata;
505 		pcbp->sockdata = NULL;
506 		switch (which) {
507 		case NG_CONTROL:
508 			sockdata->ctlsock = NULL;
509 			break;
510 		case NG_DATA:
511 			sockdata->datasock = NULL;
512 			break;
513 		default:
514 			panic(__func__);
515 		}
516 		if ((--sockdata->refs == 0) && (sockdata->node != NULL))
517 			ng_rmnode(sockdata->node);
518 	}
519 	so = pcbp->ng_socket;
520 	so->so_pcb = NULL;
521 	pcbp->ng_socket = NULL;
522 	sofree(so);		/* remove pcb ref */
523 
524 	LIST_REMOVE(pcbp, socks);
525 	FREE(pcbp, M_PCB);
526 }
527 
528 #ifdef NOTYET
529 /*
530  * File descriptors can be passed into a AF_NETGRAPH socket.
531  * Note, that file descriptors cannot be passed OUT.
532  * Only character device descriptors are accepted.
533  * Character devices are useful to connect a graph to a device,
534  * which after all is the purpose of this whole system.
535  */
536 static int
537 ng_internalize(struct mbuf *control, struct thread *td)
538 {
539 	struct filedesc *fdp = p->p_fd;
540 	const struct cmsghdr *cm = mtod(control, const struct cmsghdr *);
541 	struct file *fp;
542 	struct vnode *vn;
543 	int oldfds;
544 	int fd;
545 
546 	if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET ||
547 	    cm->cmsg_len != control->m_len) {
548 		TRAP_ERROR;
549 		return (EINVAL);
550 	}
551 
552 	/* Check there is only one FD. XXX what would more than one signify? */
553 	oldfds = (cm->cmsg_len - sizeof(*cm)) / sizeof(int);
554 	if (oldfds != 1) {
555 		TRAP_ERROR;
556 		return (EINVAL);
557 	}
558 
559 	/* Check that the FD given is legit. and change it to a pointer to a
560 	 * struct file. */
561 	fd = *(int *) (cm + 1);
562 	if ((unsigned) fd >= fdp->fd_nfiles
563 	    || (fp = fdp->fd_files[fd].fp) == NULL) {
564 		return (EBADF);
565 	}
566 
567 	/* Depending on what kind of resource it is, act differently. For
568 	 * devices, we treat it as a file. For a AF_NETGRAPH socket,
569 	 * shortcut straight to the node. */
570 	switch (fp->f_type) {
571 	case DTYPE_VNODE:
572 		vn = (struct vnode *) fp->f_data;
573 		if (vn && (vn->v_type == VCHR)) {
574 			/* for a VCHR, actually reference the FILE */
575 			fp->f_count++;
576 			/* XXX then what :) */
577 			/* how to pass on to other modules? */
578 		} else {
579 			TRAP_ERROR;
580 			return (EINVAL);
581 		}
582 		break;
583 	default:
584 		TRAP_ERROR;
585 		return (EINVAL);
586 	}
587 	return (0);
588 }
589 #endif	/* NOTYET */
590 
591 /*
592  * Connect the data socket to a named control socket node.
593  */
594 static int
595 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
596 {
597 	struct sockaddr_ng *sap;
598 	node_p farnode;
599 	struct ngsock *sockdata;
600 	int error;
601 
602 	/* If we are already connected, don't do it again */
603 	if (pcbp->sockdata != NULL)
604 		return (EISCONN);
605 
606 	/* Find the target (victim) and check it doesn't already have a data
607 	 * socket. Also check it is a 'socket' type node. */
608 	sap = (struct sockaddr_ng *) nam;
609 	if ((error = ng_path2node(NULL, sap->sg_data, &farnode, NULL)))
610 		return (error);
611 
612 	if (strcmp(farnode->type->name, NG_SOCKET_NODE_TYPE) != 0)
613 		return (EINVAL);
614 	sockdata = farnode->private;
615 	if (sockdata->datasock != NULL)
616 		return (EADDRINUSE);
617 
618 	/* Link the PCB and the private data struct. and note the extra
619 	 * reference */
620 	sockdata->datasock = pcbp;
621 	pcbp->sockdata = sockdata;
622 	sockdata->refs++;
623 	return (0);
624 }
625 
626 /*
627  * Connect the existing control socket node to a named node:hook.
628  * The hook we use on this end is the same name as the remote node name.
629  */
630 static int
631 ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp)
632 {
633 	struct ngsock *const sockdata = pcbp->sockdata;
634 	struct sockaddr_ng *sap;
635 	char *node, *hook;
636 	node_p farnode;
637 	int rtn, error;
638 
639 	sap = (struct sockaddr_ng *) nam;
640 	rtn = ng_path_parse(sap->sg_data, &node, NULL, &hook);
641 	if (rtn < 0 || node == NULL || hook == NULL) {
642 		TRAP_ERROR;
643 		return (EINVAL);
644 	}
645 	farnode = ng_findname(sockdata->node, node);
646 	if (farnode == NULL) {
647 		TRAP_ERROR;
648 		return (EADDRNOTAVAIL);
649 	}
650 
651 	/* Connect, using a hook name the same as the far node name. */
652 	error = ng_con_nodes(sockdata->node, node, farnode, hook);
653 	return error;
654 }
655 
656 /*
657  * Binding a socket means giving the corresponding node a name
658  */
659 static int
660 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
661 {
662 	struct ngsock *const sockdata = pcbp->sockdata;
663 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
664 
665 	if (sockdata == NULL) {
666 		TRAP_ERROR;
667 		return (EINVAL);
668 	}
669 	if (sap->sg_len < 3 || sap->sg_data[sap->sg_len - 3] != '\0') {
670 		TRAP_ERROR;
671 		return (EINVAL);
672 	}
673 	return (ng_name_node(sockdata->node, sap->sg_data));
674 }
675 
676 /*
677  * Take a message and pass it up to the control socket associated
678  * with the node.
679  */
680 static int
681 ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg, struct sockaddr_ng *addr)
682 {
683 	struct socket *const so = pcbp->ng_socket;
684 	struct mbuf *mdata;
685 	int msglen;
686 
687 	/* Copy the message itself into an mbuf chain */
688 	msglen = sizeof(struct ng_mesg) + msg->header.arglen;
689 	mdata = m_devget((caddr_t) msg, msglen, 0, NULL, NULL);
690 
691 	/* Here we free the message, as we are the end of the line.
692 	 * We need to do that regardless of whether we got mbufs. */
693 	FREE(msg, M_NETGRAPH);
694 
695 	if (mdata == NULL) {
696 		TRAP_ERROR;
697 		return (ENOBUFS);
698 	}
699 
700 	/* Send it up to the socket */
701 	if (ssb_appendaddr(&so->so_rcv,
702 	    (struct sockaddr *) addr, mdata, NULL) == 0) {
703 		TRAP_ERROR;
704 		m_freem(mdata);
705 		return (ENOBUFS);
706 	}
707 	sorwakeup(so);
708 	return (0);
709 }
710 
711 /*
712  * You can only create new nodes from the socket end of things.
713  */
714 static int
715 ngs_constructor(node_p *nodep)
716 {
717 	return (EINVAL);
718 }
719 
720 /*
721  * We allow any hook to be connected to the node.
722  * There is no per-hook private information though.
723  */
724 static int
725 ngs_newhook(node_p node, hook_p hook, const char *name)
726 {
727 	hook->private = node->private;
728 	return (0);
729 }
730 
731 /*
732  * Incoming messages get passed up to the control socket.
733  * Unless they are for us specifically (socket_type)
734  */
735 static int
736 ngs_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
737 	   struct ng_mesg **resp)
738 {
739 	struct ngsock *const sockdata = node->private;
740 	struct ngpcb *const pcbp = sockdata->ctlsock;
741 	struct sockaddr_ng *addr;
742 	int addrlen;
743 	int error = 0;
744 
745 	/* Only allow mesgs to be passed if we have the control socket.
746 	 * Data sockets can only support the generic messages. */
747 	if (pcbp == NULL) {
748 		TRAP_ERROR;
749 		return (EINVAL);
750 	}
751 
752 	if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
753 		switch (msg->header.cmd) {
754 		case NGM_SOCK_CMD_NOLINGER:
755 			sockdata->flags |= NGS_FLAG_NOLINGER;
756 			break;
757 		case NGM_SOCK_CMD_LINGER:
758 			sockdata->flags &= ~NGS_FLAG_NOLINGER;
759 			break;
760 		default:
761 			error = EINVAL;		/* unknown command */
762 		}
763 		/* Free the message and return */
764 		FREE(msg, M_NETGRAPH);
765 		return(error);
766 
767 	}
768 	/* Get the return address into a sockaddr */
769 	if ((retaddr == NULL) || (*retaddr == '\0'))
770 		retaddr = "";
771 	addrlen = strlen(retaddr);
772 	MALLOC(addr, struct sockaddr_ng *, addrlen + 4, M_NETGRAPH, M_NOWAIT);
773 	if (addr == NULL) {
774 		TRAP_ERROR;
775 		return (ENOMEM);
776 	}
777 	addr->sg_len = addrlen + 3;
778 	addr->sg_family = AF_NETGRAPH;
779 	bcopy(retaddr, addr->sg_data, addrlen);
780 	addr->sg_data[addrlen] = '\0';
781 
782 	/* Send it up */
783 	error = ship_msg(pcbp, msg, addr);
784 	FREE(addr, M_NETGRAPH);
785 	return (error);
786 }
787 
788 /*
789  * Receive data on a hook
790  */
791 static int
792 ngs_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
793 {
794 	struct ngsock *const sockdata = hook->node->private;
795 	struct ngpcb *const pcbp = sockdata->datasock;
796 	struct socket *so;
797 	struct sockaddr_ng *addr;
798 	char *addrbuf[NG_HOOKSIZ + 4];
799 	int addrlen;
800 
801 	/* If there is no data socket, black-hole it */
802 	if (pcbp == NULL) {
803 		NG_FREE_DATA(m, meta);
804 		return (0);
805 	}
806 	so = pcbp->ng_socket;
807 
808 	/* Get the return address into a sockaddr. */
809 	addrlen = strlen(hook->name);	/* <= NG_HOOKSIZ - 1 */
810 	addr = (struct sockaddr_ng *) addrbuf;
811 	addr->sg_len = addrlen + 3;
812 	addr->sg_family = AF_NETGRAPH;
813 	bcopy(hook->name, addr->sg_data, addrlen);
814 	addr->sg_data[addrlen] = '\0';
815 
816 	/* We have no use for the meta data, free/clear it now. */
817 	NG_FREE_META(meta);
818 
819 	/* Try to tell the socket which hook it came in on */
820 	if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *) addr, m, NULL) == 0) {
821 		m_freem(m);
822 		TRAP_ERROR;
823 		return (ENOBUFS);
824 	}
825 	sorwakeup(so);
826 	return (0);
827 }
828 
829 /*
830  * Hook disconnection
831  *
832  * For this type, removal of the last link destroys the node
833  * if the NOLINGER flag is set.
834  */
835 static int
836 ngs_disconnect(hook_p hook)
837 {
838 	struct ngsock *const sockdata = hook->node->private;
839 
840 	if ((sockdata->flags & NGS_FLAG_NOLINGER )
841 	&& (hook->node->numhooks == 0)) {
842 		ng_rmnode(hook->node);
843 	}
844 	return (0);
845 }
846 
847 /*
848  * Do local shutdown processing.
849  * In this case, that involves making sure the socket
850  * knows we should be shutting down.
851  */
852 static int
853 ngs_rmnode(node_p node)
854 {
855 	struct ngsock *const sockdata = node->private;
856 	struct ngpcb *const dpcbp = sockdata->datasock;
857 	struct ngpcb *const pcbp = sockdata->ctlsock;
858 
859 	ng_cutlinks(node);
860 	ng_unname(node);
861 
862 	if (dpcbp != NULL) {
863 		soisdisconnected(dpcbp->ng_socket);
864 		dpcbp->sockdata = NULL;
865 		sockdata->datasock = NULL;
866 		sockdata->refs--;
867 	}
868 	if (pcbp != NULL) {
869 		soisdisconnected(pcbp->ng_socket);
870 		pcbp->sockdata = NULL;
871 		sockdata->ctlsock = NULL;
872 		sockdata->refs--;
873 	}
874 	node->private = NULL;
875 	ng_unref(node);
876 	FREE(sockdata, M_NETGRAPH);
877 	return (0);
878 }
879 
880 /*
881  * Control and data socket type descriptors
882  */
883 
884 static struct pr_usrreqs ngc_usrreqs = {
885 	.pru_abort = NULL,
886 	.pru_accept = pru_accept_notsupp,
887 	.pru_attach = ngc_attach,
888 	.pru_bind = ngc_bind,
889 	.pru_connect = ngc_connect,
890 	.pru_connect2 = pru_connect2_notsupp,
891 	.pru_control = pru_control_notsupp,
892 	.pru_detach = ngc_detach,
893 	.pru_disconnect = NULL,
894 	.pru_listen = pru_listen_notsupp,
895 	.pru_peeraddr = NULL,
896 	.pru_rcvd = pru_rcvd_notsupp,
897 	.pru_rcvoob = pru_rcvoob_notsupp,
898 	.pru_send = ngc_send,
899 	.pru_sense = pru_sense_null,
900 	.pru_shutdown = NULL,
901 	.pru_sockaddr = ng_setsockaddr,
902 	.pru_sosend = sosend,
903 	.pru_soreceive = soreceive
904 };
905 
906 static struct pr_usrreqs ngd_usrreqs = {
907 	.pru_abort = NULL,
908 	.pru_accept = pru_accept_notsupp,
909 	.pru_attach = ngd_attach,
910 	.pru_bind = NULL,
911 	.pru_connect = ngd_connect,
912 	.pru_connect2 = pru_connect2_notsupp,
913 	.pru_control = pru_control_notsupp,
914 	.pru_detach = ngd_detach,
915 	.pru_disconnect = NULL,
916 	.pru_listen = pru_listen_notsupp,
917 	.pru_peeraddr = NULL,
918 	.pru_rcvd = pru_rcvd_notsupp,
919 	.pru_rcvoob = pru_rcvoob_notsupp,
920 	.pru_send = ngd_send,
921 	.pru_sense = pru_sense_null,
922 	.pru_shutdown = NULL,
923 	.pru_sockaddr = ng_setsockaddr,
924 	.pru_sosend = sosend,
925 	.pru_soreceive = soreceive
926 };
927 
928 /*
929  * Definitions of protocols supported in the NETGRAPH domain.
930  */
931 
932 extern struct domain ngdomain;		/* stop compiler warnings */
933 
934 static struct protosw ngsw[] = {
935 	{
936 		SOCK_DGRAM,
937 		&ngdomain,
938 		NG_CONTROL,
939 		PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
940 		0, 0, 0, 0,
941 		cpu0_soport, NULL,
942 		0, 0, 0, 0,
943 		&ngc_usrreqs
944 	},
945 	{
946 		SOCK_DGRAM,
947 		&ngdomain,
948 		NG_DATA,
949 		PR_ATOMIC | PR_ADDR,
950 		0, 0, 0, 0,
951 		cpu0_soport, NULL,
952 		0, 0, 0, 0,
953 		&ngd_usrreqs
954 	}
955 };
956 
957 struct domain ngdomain = {
958 	AF_NETGRAPH, "netgraph", NULL, NULL, NULL,
959 	ngsw, &ngsw[sizeof(ngsw) / sizeof(ngsw[0])],
960 };
961 
962 /*
963  * Handle loading and unloading for this node type
964  * This is to handle auxiliary linkages (e.g protocol domain addition).
965  */
966 static int
967 ngs_mod_event(module_t mod, int event, void *data)
968 {
969 	int error = 0;
970 
971 	switch (event) {
972 	case MOD_LOAD:
973 		/* Register protocol domain */
974 		net_add_domain(&ngdomain);
975 		break;
976 	case MOD_UNLOAD:
977 		/* Insure there are no open netgraph sockets */
978 		if (!LIST_EMPTY(&ngsocklist)) {
979 			error = EBUSY;
980 			break;
981 		}
982 
983 #ifdef NOTYET
984 		/* Unregister protocol domain XXX can't do this yet.. */
985 		if ((error = net_rm_domain(&ngdomain)) != 0)
986 			break;
987 #else
988 		error = EBUSY;
989 #endif
990 		break;
991 	default:
992 		error = EOPNOTSUPP;
993 		break;
994 	}
995 	return (error);
996 }
997 
998 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, 0, AF_NETGRAPH, "");
999 SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW, 0, "DATA");
1000 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, 0, NG_DATA, "");
1001 SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW, 0, "CONTROL");
1002 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, 0, NG_CONTROL, "");
1003 
1004