xref: /freebsd/sys/netgraph/ng_socket.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
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  * $FreeBSD$
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/domain.h>
54 #include <sys/errno.h>
55 #include <sys/kernel.h>
56 #include <sys/filedesc.h>
57 #include <sys/malloc.h>
58 #include <sys/queue.h>
59 #include <sys/mbuf.h>
60 #include <sys/protosw.h>
61 #include <sys/socket.h>
62 #include <sys/socketvar.h>
63 #include <sys/sysctl.h>
64 #ifdef NOTYET
65 #include <sys/vnode.h>
66 #endif
67 #include <netgraph/ng_message.h>
68 #include <netgraph/netgraph.h>
69 #include <netgraph/ng_socketvar.h>
70 #include <netgraph/ng_socket.h>
71 
72 /*
73  * It's Ascii-art time!
74  *   +-------------+   +-------------+
75  *   |socket  (ctl)|   |socket (data)|
76  *   +-------------+   +-------------+
77  *          ^                 ^
78  *          |                 |
79  *          v                 v
80  *    +-----------+     +-----------+
81  *    |pcb   (ctl)|     |pcb  (data)|
82  *    +-----------+     +-----------+
83  *          ^                 ^
84  *          |                 |
85  *          v                 v
86  *      +--------------------------+
87  *      |   Socket type private    |
88  *      |       data               |
89  *      +--------------------------+
90  *                   ^
91  *                   |
92  *                   v
93  *           +----------------+
94  *           | struct ng_node |
95  *           +----------------+
96  */
97 
98 /* Netgraph node methods */
99 static ng_constructor_t	ngs_constructor;
100 static ng_rcvmsg_t	ngs_rcvmsg;
101 static ng_shutdown_t	ngs_rmnode;
102 static ng_newhook_t	ngs_newhook;
103 static ng_rcvdata_t	ngs_rcvdata;
104 static ng_disconnect_t	ngs_disconnect;
105 
106 /* Internal methods */
107 static int	ng_attach_data(struct socket *so);
108 static int	ng_attach_cntl(struct socket *so);
109 static int	ng_attach_common(struct socket *so, int type);
110 static void	ng_detach_common(struct ngpcb *pcbp, int type);
111 /*static int	ng_internalize(struct mbuf *m, struct proc *p); */
112 
113 static int	ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp);
114 static int	ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp);
115 static int	ng_bind(struct sockaddr *nam, struct ngpcb *pcbp);
116 
117 static int	ngs_mod_event(module_t mod, int event, void *data);
118 static int	ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg,
119 			struct sockaddr_ng *addr);
120 
121 /* Netgraph type descriptor */
122 static struct ng_type typestruct = {
123 	NG_VERSION,
124 	NG_SOCKET_NODE_TYPE,
125 	ngs_mod_event,
126 	ngs_constructor,
127 	ngs_rcvmsg,
128 	ngs_rmnode,
129 	ngs_newhook,
130 	NULL,
131 	NULL,
132 	ngs_rcvdata,
133 	ngs_rcvdata,
134 	ngs_disconnect,
135 	NULL
136 };
137 NETGRAPH_INIT(socket, &typestruct);
138 
139 /* Buffer space */
140 static u_long ngpdg_sendspace = 20 * 1024;	/* really max datagram size */
141 static u_long ngpdg_recvspace = 20 * 1024;
142 
143 /* List of all sockets */
144 LIST_HEAD(, ngpcb) ngsocklist;
145 
146 #define sotongpcb(so) ((struct ngpcb *)(so)->so_pcb)
147 
148 /* If getting unexplained errors returned, set this to "Debugger("X"); */
149 #ifndef TRAP_ERROR
150 #define TRAP_ERROR
151 #endif
152 
153 /***************************************************************
154 	Control sockets
155 ***************************************************************/
156 
157 static int
158 ngc_attach(struct socket *so, int proto, struct proc *p)
159 {
160 	struct ngpcb *const pcbp = sotongpcb(so);
161 
162 	if (suser(p))
163 		return (EPERM);
164 	if (pcbp != NULL)
165 		return (EISCONN);
166 	return (ng_attach_cntl(so));
167 }
168 
169 static int
170 ngc_detach(struct socket *so)
171 {
172 	struct ngpcb *const pcbp = sotongpcb(so);
173 
174 	if (pcbp == NULL)
175 		return (EINVAL);
176 	ng_detach_common(pcbp, NG_CONTROL);
177 	return (0);
178 }
179 
180 static int
181 ngc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
182 	 struct mbuf *control, struct proc *p)
183 {
184 	struct ngpcb *const pcbp = sotongpcb(so);
185 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
186 	struct ng_mesg *resp;
187 	struct mbuf *m0;
188 	char *msg, *path = NULL;
189 	int len, error = 0;
190 
191 	if (pcbp == NULL) {
192 		error = EINVAL;
193 		goto release;
194 	}
195 #ifdef	NOTYET
196 	if (control && (error = ng_internalize(control, p))) {
197 		if (pcbp->sockdata == NULL) {
198 			error = ENOTCONN;
199 			goto release;
200 		}
201 	}
202 #else	/* NOTYET */
203 	if (control) {
204 		error = EINVAL;
205 		goto release;
206 	}
207 #endif	/* NOTYET */
208 
209 	/* Require destination as there may be >= 1 hooks on this node */
210 	if (addr == NULL) {
211 		error = EDESTADDRREQ;
212 		goto release;
213 	}
214 
215 	/* Allocate an expendable buffer for the path, chop off
216 	 * the sockaddr header, and make sure it's NUL terminated */
217 	len = sap->sg_len - 2;
218 	MALLOC(path, char *, len + 1, M_NETGRAPH, M_WAITOK);
219 	if (path == NULL) {
220 		error = ENOMEM;
221 		goto release;
222 	}
223 	bcopy(sap->sg_data, path, len);
224 	path[len] = '\0';
225 
226 	/* Move the actual message out of mbufs into a linear buffer.
227 	 * Start by adding up the size of the data. (could use mh_len?) */
228 	for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
229 		len += m0->m_len;
230 
231 	/* Move the data into a linear buffer as well. Messages are not
232 	 * delivered in mbufs. */
233 	MALLOC(msg, char *, len + 1, M_NETGRAPH, M_WAITOK);
234 	if (msg == NULL) {
235 		error = ENOMEM;
236 		goto release;
237 	}
238 	m_copydata(m, 0, len, msg);
239 
240 	/* The callee will free the msg when done. The addr is our business. */
241 	error = ng_send_msg(pcbp->sockdata->node,
242 			    (struct ng_mesg *) msg, path, &resp);
243 
244 	/* If the callee responded with a synchronous response, then put it
245 	 * back on the receive side of the socket; sap is source address. */
246 	if (error == 0 && resp != NULL)
247 		error = ship_msg(pcbp, resp, sap);
248 
249 release:
250 	if (path != NULL)
251 		FREE(path, M_NETGRAPH);
252 	if (control != NULL)
253 		m_freem(control);
254 	if (m != NULL)
255 		m_freem(m);
256 	return (error);
257 }
258 
259 static int
260 ngc_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
261 {
262 	struct ngpcb *const pcbp = sotongpcb(so);
263 
264 	if (pcbp == 0)
265 		return (EINVAL);
266 	return (ng_bind(nam, pcbp));
267 }
268 
269 static int
270 ngc_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
271 {
272 	struct ngpcb *const pcbp = sotongpcb(so);
273 
274 	if (pcbp == 0)
275 		return (EINVAL);
276 	return (ng_connect_cntl(nam, pcbp));
277 }
278 
279 /***************************************************************
280 	Data sockets
281 ***************************************************************/
282 
283 static int
284 ngd_attach(struct socket *so, int proto, struct proc *p)
285 {
286 	struct ngpcb *const pcbp = sotongpcb(so);
287 
288 	if (pcbp != NULL)
289 		return (EISCONN);
290 	return (ng_attach_data(so));
291 }
292 
293 static int
294 ngd_detach(struct socket *so)
295 {
296 	struct ngpcb *const pcbp = sotongpcb(so);
297 
298 	if (pcbp == NULL)
299 		return (EINVAL);
300 	ng_detach_common(pcbp, NG_DATA);
301 	return (0);
302 }
303 
304 static int
305 ngd_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
306 	 struct mbuf *control, struct proc *p)
307 {
308 	struct ngpcb *const pcbp = sotongpcb(so);
309 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
310 	meta_p  mp = NULL;
311 	int     len, error;
312 	hook_p  hook = NULL;
313 	char	hookname[NG_HOOKLEN + 1];
314 
315 	if ((pcbp == NULL) || (control != NULL)) {
316 		error = EINVAL;
317 		goto release;
318 	}
319 	if (pcbp->sockdata == NULL) {
320 		error = ENOTCONN;
321 		goto release;
322 	}
323 	/*
324 	 * If the user used any of these ways to not specify an address
325 	 * then handle specially.
326 	 */
327 	if ((sap == NULL)
328 	|| ((len = sap->sg_len) <= 2)
329 	|| (*sap->sg_data == '\0')) {
330 		if (pcbp->sockdata->node->numhooks != 1) {
331 			error = EDESTADDRREQ;
332 			goto release;
333 		}
334 		/*
335 		 * if exactly one hook exists, just use it.
336 		 * Special case to allow write(2) to work on an ng_socket.
337 		 */
338 		hook = LIST_FIRST(&pcbp->sockdata->node->hooks);
339 	} else {
340 		if (len > NG_HOOKLEN) {
341 			error = EINVAL;
342 			goto release;
343 		}
344 
345 		/*
346 		 * chop off the sockaddr header, and make sure it's NUL
347 		 * terminated
348 		 */
349 		bcopy(sap->sg_data, hookname, len);
350 		hookname[len] = '\0';
351 
352 		/* Find the correct hook from 'hookname' */
353 		LIST_FOREACH(hook, &pcbp->sockdata->node->hooks, hooks) {
354 			if (strcmp(hookname, hook->name) == 0)
355 				break;
356 		}
357 		if (hook == NULL)
358 			error = EHOSTUNREACH;
359 	}
360 
361 	/* Send data (OK if hook is NULL) */
362 	NG_SEND_DATA(error, hook, m, mp);	/* makes m NULL */
363 
364 release:
365 	if (control != NULL)
366 		m_freem(control);
367 	if (m != NULL)
368 		m_freem(m);
369 	return (error);
370 }
371 
372 static int
373 ngd_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
374 {
375 	struct ngpcb *const pcbp = sotongpcb(so);
376 
377 	if (pcbp == 0)
378 		return (EINVAL);
379 	return (ng_connect_data(nam, pcbp));
380 }
381 
382 /*
383  * Used for both data and control sockets
384  */
385 static int
386 ng_setsockaddr(struct socket *so, struct sockaddr **addr)
387 {
388 	struct ngpcb *pcbp;
389 	struct sockaddr_ng *sg;
390 	int sg_len, namelen, s;
391 
392 	/* Why isn't sg_data a `char[1]' ? :-( */
393 	sg_len = sizeof(struct sockaddr_ng) - sizeof(sg->sg_data) + 1;
394 
395 	s = splnet();
396 	pcbp = sotongpcb(so);
397 	if (pcbp == 0) {
398 		splx(s);
399 		return (EINVAL);
400 	}
401 
402 	namelen = 0;		/* silence compiler ! */
403 
404 	if (pcbp->sockdata->node->name != NULL)
405 		sg_len += namelen = strlen(pcbp->sockdata->node->name);
406 
407 	MALLOC(sg, struct sockaddr_ng *, sg_len, M_SONAME, M_WAITOK | M_ZERO);
408 
409 	if (pcbp->sockdata->node->name != NULL)
410 		bcopy(pcbp->sockdata->node->name, sg->sg_data, namelen);
411 	splx(s);
412 
413 	sg->sg_len = sg_len;
414 	sg->sg_family = AF_NETGRAPH;
415 	*addr = (struct sockaddr *)sg;
416 
417 	return (0);
418 }
419 
420 /*
421  * Attach a socket to it's protocol specific partner.
422  * For a control socket, actually create a netgraph node and attach
423  * to it as well.
424  */
425 
426 static int
427 ng_attach_cntl(struct socket *so)
428 {
429 	struct ngsock *privdata;
430 	struct ngpcb *pcbp;
431 	int error;
432 
433 	/* Setup protocol control block */
434 	if ((error = ng_attach_common(so, NG_CONTROL)) != 0)
435 		return (error);
436 	pcbp = sotongpcb(so);
437 
438 	/* Allocate node private info */
439 	MALLOC(privdata, struct ngsock *,
440 	    sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO);
441 	if (privdata == NULL) {
442 		ng_detach_common(pcbp, NG_CONTROL);
443 		return (ENOMEM);
444 	}
445 
446 	/* Make the generic node components */
447 	if ((error = ng_make_node_common(&typestruct, &privdata->node)) != 0) {
448 		FREE(privdata, M_NETGRAPH);
449 		ng_detach_common(pcbp, NG_CONTROL);
450 		return (error);
451 	}
452 	privdata->node->private = privdata;
453 
454 	/* Link the pcb and the node private data */
455 	privdata->ctlsock = pcbp;
456 	pcbp->sockdata = privdata;
457 	privdata->refs++;
458 	return (0);
459 }
460 
461 static int
462 ng_attach_data(struct socket *so)
463 {
464 	return(ng_attach_common(so, NG_DATA));
465 }
466 
467 /*
468  * Set up a socket protocol control block.
469  * This code is shared between control and data sockets.
470  */
471 static int
472 ng_attach_common(struct socket *so, int type)
473 {
474 	struct ngpcb *pcbp;
475 	int error;
476 
477 	/* Standard socket setup stuff */
478 	error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace);
479 	if (error)
480 		return (error);
481 
482 	/* Allocate the pcb */
483 	MALLOC(pcbp, struct ngpcb *, sizeof(*pcbp), M_PCB, M_WAITOK | M_ZERO);
484 	if (pcbp == NULL)
485 		return (ENOMEM);
486 	pcbp->type = type;
487 
488 	/* Link the pcb and the socket */
489 	so->so_pcb = (caddr_t) pcbp;
490 	pcbp->ng_socket = so;
491 
492 	/* Add the socket to linked list */
493 	LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
494 	return (0);
495 }
496 
497 /*
498  * Disassociate the socket from it's protocol specific
499  * partner. If it's attached to a node's private data structure,
500  * then unlink from that too. If we were the last socket attached to it,
501  * then shut down the entire node. Shared code for control and data sockets.
502  */
503 static void
504 ng_detach_common(struct ngpcb *pcbp, int which)
505 {
506 	struct ngsock *sockdata;
507 
508 	if (pcbp->sockdata) {
509 		sockdata = pcbp->sockdata;
510 		pcbp->sockdata = NULL;
511 		switch (which) {
512 		case NG_CONTROL:
513 			sockdata->ctlsock = NULL;
514 			break;
515 		case NG_DATA:
516 			sockdata->datasock = NULL;
517 			break;
518 		default:
519 			panic(__FUNCTION__);
520 		}
521 		if ((--sockdata->refs == 0) && (sockdata->node != NULL))
522 			ng_rmnode(sockdata->node);
523 	}
524 	pcbp->ng_socket->so_pcb = NULL;
525 	pcbp->ng_socket = NULL;
526 	LIST_REMOVE(pcbp, socks);
527 	FREE(pcbp, M_PCB);
528 }
529 
530 #ifdef NOTYET
531 /*
532  * File descriptors can be passed into a AF_NETGRAPH socket.
533  * Note, that file descriptors cannot be passed OUT.
534  * Only character device descriptors are accepted.
535  * Character devices are useful to connect a graph to a device,
536  * which after all is the purpose of this whole system.
537  */
538 static int
539 ng_internalize(struct mbuf *control, struct proc *p)
540 {
541 	struct filedesc *fdp = p->p_fd;
542 	struct cmsghdr *cm = mtod(control, struct cmsghdr *);
543 	struct file *fp;
544 	struct vnode *vn;
545 	int oldfds;
546 	int fd;
547 
548 	if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET ||
549 	    cm->cmsg_len != control->m_len) {
550 		TRAP_ERROR;
551 		return (EINVAL);
552 	}
553 
554 	/* Check there is only one FD. XXX what would more than one signify? */
555 	oldfds = (cm->cmsg_len - sizeof(*cm)) / sizeof(int);
556 	if (oldfds != 1) {
557 		TRAP_ERROR;
558 		return (EINVAL);
559 	}
560 
561 	/* Check that the FD given is legit. and change it to a pointer to a
562 	 * struct file. */
563 	fd = *(int *) (cm + 1);
564 	if ((unsigned) fd >= fdp->fd_nfiles
565 	    || (fp = fdp->fd_ofiles[fd]) == NULL) {
566 		return (EBADF);
567 	}
568 
569 	/* Depending on what kind of resource it is, act differently. For
570 	 * devices, we treat it as a file. For a AF_NETGRAPH socket,
571 	 * shortcut straight to the node. */
572 	switch (fp->f_type) {
573 	case DTYPE_VNODE:
574 		vn = (struct vnode *) fp->f_data;
575 		if (vn && (vn->v_type == VCHR)) {
576 			/* for a VCHR, actually reference the FILE */
577 			fp->f_count++;
578 			/* XXX then what :) */
579 			/* how to pass on to other modules? */
580 		} else {
581 			TRAP_ERROR;
582 			return (EINVAL);
583 		}
584 		break;
585 	default:
586 		TRAP_ERROR;
587 		return (EINVAL);
588 	}
589 	return (0);
590 }
591 #endif	/* NOTYET */
592 
593 /*
594  * Connect the data socket to a named control socket node.
595  */
596 static int
597 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
598 {
599 	struct sockaddr_ng *sap;
600 	node_p farnode;
601 	struct ngsock *sockdata;
602 	int error;
603 
604 	/* If we are already connected, don't do it again */
605 	if (pcbp->sockdata != NULL)
606 		return (EISCONN);
607 
608 	/* Find the target (victim) and check it doesn't already have a data
609 	 * socket. Also check it is a 'socket' type node. */
610 	sap = (struct sockaddr_ng *) nam;
611 	if ((error = ng_path2node(NULL, sap->sg_data, &farnode, NULL, NULL)))
612 		return (error);
613 
614 	if (strcmp(farnode->type->name, NG_SOCKET_NODE_TYPE) != 0)
615 		return (EINVAL);
616 	sockdata = farnode->private;
617 	if (sockdata->datasock != NULL)
618 		return (EADDRINUSE);
619 
620 	/* Link the PCB and the private data struct. and note the extra
621 	 * reference */
622 	sockdata->datasock = pcbp;
623 	pcbp->sockdata = sockdata;
624 	sockdata->refs++;
625 	return (0);
626 }
627 
628 /*
629  * Connect the existing control socket node to a named node:hook.
630  * The hook we use on this end is the same name as the remote node name.
631  */
632 static int
633 ng_connect_cntl(struct sockaddr *nam, struct ngpcb *pcbp)
634 {
635 	struct ngsock *const sockdata = pcbp->sockdata;
636 	struct sockaddr_ng *sap;
637 	char *node, *hook;
638 	node_p farnode;
639 	int rtn, error;
640 
641 	sap = (struct sockaddr_ng *) nam;
642 	rtn = ng_path_parse(sap->sg_data, &node, NULL, &hook);
643 	if (rtn < 0 || node == NULL || hook == NULL) {
644 		TRAP_ERROR;
645 		return (EINVAL);
646 	}
647 	farnode = ng_findname(sockdata->node, node);
648 	if (farnode == NULL) {
649 		TRAP_ERROR;
650 		return (EADDRNOTAVAIL);
651 	}
652 
653 	/* Connect, using a hook name the same as the far node name. */
654 	error = ng_con_nodes(sockdata->node, node, farnode, hook);
655 	return error;
656 }
657 
658 /*
659  * Binding a socket means giving the corresponding node a name
660  */
661 static int
662 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
663 {
664 	struct ngsock *const sockdata = pcbp->sockdata;
665 	struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
666 
667 	if (sockdata == NULL) {
668 		TRAP_ERROR;
669 		return (EINVAL);
670 	}
671 	if (sap->sg_len < 3 || sap->sg_data[sap->sg_len - 3] != '\0') {
672 		TRAP_ERROR;
673 		return (EINVAL);
674 	}
675 	return (ng_name_node(sockdata->node, sap->sg_data));
676 }
677 
678 /*
679  * Take a message and pass it up to the control socket associated
680  * with the node.
681  */
682 static int
683 ship_msg(struct ngpcb *pcbp, struct ng_mesg *msg, struct sockaddr_ng *addr)
684 {
685 	struct socket *const so = pcbp->ng_socket;
686 	struct mbuf *mdata;
687 	int msglen;
688 
689 	/* Copy the message itself into an mbuf chain */
690 	msglen = sizeof(struct ng_mesg) + msg->header.arglen;
691 	mdata = m_devget((caddr_t) msg, msglen, 0, NULL, NULL);
692 
693 	/* Here we free the message, as we are the end of the line.
694 	 * We need to do that regardless of whether we got mbufs. */
695 	FREE(msg, M_NETGRAPH);
696 
697 	if (mdata == NULL) {
698 		TRAP_ERROR;
699 		return (ENOBUFS);
700 	}
701 
702 	/* Send it up to the socket */
703 	if (sbappendaddr(&so->so_rcv,
704 	    (struct sockaddr *) addr, mdata, NULL) == 0) {
705 		TRAP_ERROR;
706 		m_freem(mdata);
707 		return (ENOBUFS);
708 	}
709 	sorwakeup(so);
710 	return (0);
711 }
712 
713 /*
714  * You can only create new nodes from the socket end of things.
715  */
716 static int
717 ngs_constructor(node_p *nodep)
718 {
719 	return (EINVAL);
720 }
721 
722 /*
723  * We allow any hook to be connected to the node.
724  * There is no per-hook private information though.
725  */
726 static int
727 ngs_newhook(node_p node, hook_p hook, const char *name)
728 {
729 	hook->private = node->private;
730 	return (0);
731 }
732 
733 /*
734  * Incoming messages get passed up to the control socket.
735  * Unless they are for us specifically (socket_type)
736  */
737 static int
738 ngs_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
739 	   struct ng_mesg **resp, hook_p lasthook)
740 {
741 	struct ngsock *const sockdata = node->private;
742 	struct ngpcb *const pcbp = sockdata->ctlsock;
743 	struct sockaddr_ng *addr;
744 	int addrlen;
745 	int error = 0;
746 
747 	/* Only allow mesgs to be passed if we have the control socket.
748 	 * Data sockets can only support the generic messages. */
749 	if (pcbp == NULL) {
750 		TRAP_ERROR;
751 		return (EINVAL);
752 	}
753 
754 	if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
755 		switch (msg->header.cmd) {
756 		case NGM_SOCK_CMD_NOLINGER:
757 			sockdata->flags |= NGS_FLAG_NOLINGER;
758 			break;
759 		case NGM_SOCK_CMD_LINGER:
760 			sockdata->flags &= ~NGS_FLAG_NOLINGER;
761 			break;
762 		default:
763 			error = EINVAL;		/* unknown command */
764 		}
765 		/* Free the message and return */
766 		FREE(msg, M_NETGRAPH);
767 		return(error);
768 
769 	}
770 	/* Get the return address into a sockaddr */
771 	if ((retaddr == NULL) || (*retaddr == '\0'))
772 		retaddr = "";
773 	addrlen = strlen(retaddr);
774 	MALLOC(addr, struct sockaddr_ng *, addrlen + 4, M_NETGRAPH, M_NOWAIT);
775 	if (addr == NULL) {
776 		TRAP_ERROR;
777 		return (ENOMEM);
778 	}
779 	addr->sg_len = addrlen + 3;
780 	addr->sg_family = AF_NETGRAPH;
781 	bcopy(retaddr, addr->sg_data, addrlen);
782 	addr->sg_data[addrlen] = '\0';
783 
784 	/* Send it up */
785 	error = ship_msg(pcbp, msg, addr);
786 	FREE(addr, M_NETGRAPH);
787 	return (error);
788 }
789 
790 /*
791  * Receive data on a hook
792  */
793 static int
794 ngs_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
795 		struct mbuf **ret_m, meta_p *ret_meta)
796 {
797 	struct ngsock *const sockdata = hook->node->private;
798 	struct ngpcb *const pcbp = sockdata->datasock;
799 	struct socket *so;
800 	struct sockaddr_ng *addr;
801 	char *addrbuf[NG_HOOKLEN + 1 + 4];
802 	int addrlen;
803 
804 	/* If there is no data socket, black-hole it */
805 	if (pcbp == NULL) {
806 		NG_FREE_DATA(m, meta);
807 		return (0);
808 	}
809 	so = pcbp->ng_socket;
810 
811 	/* Get the return address into a sockaddr. */
812 	addrlen = strlen(hook->name);	/* <= NG_HOOKLEN */
813 	addr = (struct sockaddr_ng *) addrbuf;
814 	addr->sg_len = addrlen + 3;
815 	addr->sg_family = AF_NETGRAPH;
816 	bcopy(hook->name, addr->sg_data, addrlen);
817 	addr->sg_data[addrlen] = '\0';
818 
819 	/* We have no use for the meta data, free/clear it now. */
820 	NG_FREE_META(meta);
821 
822 	/* Try to tell the socket which hook it came in on */
823 	if (sbappendaddr(&so->so_rcv, (struct sockaddr *) addr, m, NULL) == 0) {
824 		m_freem(m);
825 		TRAP_ERROR;
826 		return (ENOBUFS);
827 	}
828 	sorwakeup(so);
829 	return (0);
830 }
831 
832 /*
833  * Hook disconnection
834  *
835  * For this type, removal of the last link destroys the node
836  * if the NOLINGER flag is set.
837  */
838 static int
839 ngs_disconnect(hook_p hook)
840 {
841 	struct ngsock *const sockdata = hook->node->private;
842 
843 	if ((sockdata->flags & NGS_FLAG_NOLINGER )
844 	&& (hook->node->numhooks == 0)) {
845 		ng_rmnode(hook->node);
846 	}
847 	return (0);
848 }
849 
850 /*
851  * Do local shutdown processing.
852  * In this case, that involves making sure the socket
853  * knows we should be shutting down.
854  */
855 static int
856 ngs_rmnode(node_p node)
857 {
858 	struct ngsock *const sockdata = node->private;
859 	struct ngpcb *const dpcbp = sockdata->datasock;
860 	struct ngpcb *const pcbp = sockdata->ctlsock;
861 
862 	ng_cutlinks(node);
863 	ng_unname(node);
864 
865 	if (dpcbp != NULL) {
866 		soisdisconnected(dpcbp->ng_socket);
867 		dpcbp->sockdata = NULL;
868 		sockdata->datasock = NULL;
869 		sockdata->refs--;
870 	}
871 	if (pcbp != NULL) {
872 		soisdisconnected(pcbp->ng_socket);
873 		pcbp->sockdata = NULL;
874 		sockdata->ctlsock = NULL;
875 		sockdata->refs--;
876 	}
877 	node->private = NULL;
878 	ng_unref(node);
879 	FREE(sockdata, M_NETGRAPH);
880 	return (0);
881 }
882 
883 /*
884  * Control and data socket type descriptors
885  */
886 
887 static struct pr_usrreqs ngc_usrreqs = {
888 	NULL,			/* abort */
889 	pru_accept_notsupp,
890 	ngc_attach,
891 	ngc_bind,
892 	ngc_connect,
893 	pru_connect2_notsupp,
894 	pru_control_notsupp,
895 	ngc_detach,
896 	NULL,			/* disconnect */
897 	pru_listen_notsupp,
898 	NULL,			/* setpeeraddr */
899 	pru_rcvd_notsupp,
900 	pru_rcvoob_notsupp,
901 	ngc_send,
902 	pru_sense_null,
903 	NULL,			/* shutdown */
904 	ng_setsockaddr,
905 	sosend,
906 	soreceive,
907 	sopoll
908 };
909 
910 static struct pr_usrreqs ngd_usrreqs = {
911 	NULL,			/* abort */
912 	pru_accept_notsupp,
913 	ngd_attach,
914 	NULL,			/* bind */
915 	ngd_connect,
916 	pru_connect2_notsupp,
917 	pru_control_notsupp,
918 	ngd_detach,
919 	NULL,			/* disconnect */
920 	pru_listen_notsupp,
921 	NULL,			/* setpeeraddr */
922 	pru_rcvd_notsupp,
923 	pru_rcvoob_notsupp,
924 	ngd_send,
925 	pru_sense_null,
926 	NULL,			/* shutdown */
927 	ng_setsockaddr,
928 	sosend,
929 	soreceive,
930 	sopoll
931 };
932 
933 /*
934  * Definitions of protocols supported in the NETGRAPH domain.
935  */
936 
937 extern struct domain ngdomain;		/* stop compiler warnings */
938 
939 static struct protosw ngsw[] = {
940 	{
941 		SOCK_DGRAM,
942 		&ngdomain,
943 		NG_CONTROL,
944 		PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
945 		0, 0, 0, 0,
946 		NULL,
947 		0, 0, 0, 0,
948 		&ngc_usrreqs
949 	},
950 	{
951 		SOCK_DGRAM,
952 		&ngdomain,
953 		NG_DATA,
954 		PR_ATOMIC | PR_ADDR,
955 		0, 0, 0, 0,
956 		NULL,
957 		0, 0, 0, 0,
958 		&ngd_usrreqs
959 	}
960 };
961 
962 struct domain ngdomain = {
963 	AF_NETGRAPH,
964 	"netgraph",
965 	0,
966 	NULL,
967 	NULL,
968 	ngsw,
969 	&ngsw[sizeof(ngsw) / sizeof(ngsw[0])],
970 	0,
971 	NULL,
972 	0,
973 	0
974 };
975 
976 /*
977  * Handle loading and unloading for this node type
978  * This is to handle auxiliary linkages (e.g protocol domain addition).
979  */
980 static int
981 ngs_mod_event(module_t mod, int event, void *data)
982 {
983 	int error = 0;
984 
985 	switch (event) {
986 	case MOD_LOAD:
987 		/* Register protocol domain */
988 		net_add_domain(&ngdomain);
989 		break;
990 	case MOD_UNLOAD:
991 		/* Insure there are no open netgraph sockets */
992 		if (!LIST_EMPTY(&ngsocklist)) {
993 			error = EBUSY;
994 			break;
995 		}
996 
997 #ifdef NOTYET
998 		/* Unregister protocol domain XXX can't do this yet.. */
999 		if ((error = net_rm_domain(&ngdomain)) != 0)
1000 			break;
1001 #else
1002 		error = EBUSY;
1003 #endif
1004 		break;
1005 	default:
1006 		error = EOPNOTSUPP;
1007 		break;
1008 	}
1009 	return (error);
1010 }
1011 
1012 SYSCTL_NODE(_net, AF_NETGRAPH, graph, CTLFLAG_RW, 0, "netgraph Family");
1013 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, 0, AF_NETGRAPH, "");
1014 SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW, 0, "DATA");
1015 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, 0, NG_DATA, "");
1016 SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW, 0, "CONTROL");
1017 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, 0, NG_CONTROL, "");
1018 
1019