1 /*
2 * ng_socket.c
3 */
4
5 /*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Author: Julian Elischer <julian@freebsd.org>
39 *
40 * $FreeBSD: releng/8.2/sys/netgraph/ng_socket.c 208690 2010-06-01 09:32:22Z attilio $
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/domain.h>
54 #include <sys/kernel.h>
55 #include <sys/linker.h>
56 #include <sys/lock.h>
57 #include <sys/malloc.h>
58 #include <sys/mbuf.h>
59 #include <sys/mutex.h>
60 #include <sys/priv.h>
61 #include <sys/protosw.h>
62 #include <sys/queue.h>
63 #include <sys/socket.h>
64 #include <sys/socketvar.h>
65 #include <sys/syscallsubr.h>
66 #include <sys/sysctl.h>
67 #ifdef NOTYET
68 #include <sys/vnode.h>
69 #endif
70
71 #include <net/vnet.h>
72
73 #include <netgraph/ng_message.h>
74 #include <netgraph/netgraph.h>
75 #include <netgraph/ng_socketvar.h>
76 #include <netgraph/ng_socket.h>
77
78 #ifdef NG_SEPARATE_MALLOC
79 MALLOC_DEFINE(M_NETGRAPH_PATH, "netgraph_path", "netgraph path info ");
80 MALLOC_DEFINE(M_NETGRAPH_SOCK, "netgraph_sock", "netgraph socket info ");
81 #else
82 #define M_NETGRAPH_PATH M_NETGRAPH
83 #define M_NETGRAPH_SOCK M_NETGRAPH
84 #endif
85
86 /*
87 * It's Ascii-art time!
88 * +-------------+ +-------------+
89 * |socket (ctl)| |socket (data)|
90 * +-------------+ +-------------+
91 * ^ ^
92 * | |
93 * v v
94 * +-----------+ +-----------+
95 * |pcb (ctl)| |pcb (data)|
96 * +-----------+ +-----------+
97 * ^ ^
98 * | |
99 * v v
100 * +--------------------------+
101 * | Socket type private |
102 * | data |
103 * +--------------------------+
104 * ^
105 * |
106 * v
107 * +----------------+
108 * | struct ng_node |
109 * +----------------+
110 */
111
112 /* Netgraph node methods */
113 static ng_constructor_t ngs_constructor;
114 static ng_rcvmsg_t ngs_rcvmsg;
115 static ng_shutdown_t ngs_shutdown;
116 static ng_newhook_t ngs_newhook;
117 static ng_connect_t ngs_connect;
118 static ng_rcvdata_t ngs_rcvdata;
119 static ng_disconnect_t ngs_disconnect;
120
121 /* Internal methods */
122 static int ng_attach_data(struct socket *so);
123 static int ng_attach_cntl(struct socket *so);
124 static int ng_attach_common(struct socket *so, int type);
125 static void ng_detach_common(struct ngpcb *pcbp, int type);
126 static void ng_socket_free_priv(struct ngsock *priv);
127 #ifdef NOTYET
128 static int ng_internalize(struct mbuf *m, struct thread *p);
129 #endif
130 static int ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp);
131 static int ng_bind(struct sockaddr *nam, struct ngpcb *pcbp);
132
133 static int ngs_mod_event(module_t mod, int event, void *data);
134 static void ng_socket_item_applied(void *context, int error);
135
136 /* Netgraph type descriptor */
137 static struct ng_type typestruct = {
138 .version = NG_ABI_VERSION,
139 .name = NG_SOCKET_NODE_TYPE,
140 .mod_event = ngs_mod_event,
141 .constructor = ngs_constructor,
142 .rcvmsg = ngs_rcvmsg,
143 .shutdown = ngs_shutdown,
144 .newhook = ngs_newhook,
145 .connect = ngs_connect,
146 .rcvdata = ngs_rcvdata,
147 .disconnect = ngs_disconnect,
148 };
149 NETGRAPH_INIT_ORDERED(socket, &typestruct, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);
150
151 /* Buffer space */
152 static u_long ngpdg_sendspace = 20 * 1024; /* really max datagram size */
153 SYSCTL_INT(_net_graph, OID_AUTO, maxdgram, CTLFLAG_RW,
154 &ngpdg_sendspace , 0, "Maximum outgoing Netgraph datagram size");
155 static u_long ngpdg_recvspace = 20 * 1024;
156 SYSCTL_INT(_net_graph, OID_AUTO, recvspace, CTLFLAG_RW,
157 &ngpdg_recvspace , 0, "Maximum space for incoming Netgraph datagrams");
158
159 /* List of all sockets (for netstat -f netgraph) */
160 static LIST_HEAD(, ngpcb) ngsocklist;
161
162 static struct mtx ngsocketlist_mtx;
163
164 #define sotongpcb(so) ((struct ngpcb *)(so)->so_pcb)
165
166 /* If getting unexplained errors returned, set this to "kdb_enter("X"); */
167 #ifndef TRAP_ERROR
168 #define TRAP_ERROR
169 #endif
170
171 /***************************************************************
172 Control sockets
173 ***************************************************************/
174
175 static int
176 ngc_attach(struct socket *so, int proto, struct thread *td)
177 {
178 struct ngpcb *const pcbp = sotongpcb(so);
179 int error;
180
181 error = priv_check(td, PRIV_NETGRAPH_CONTROL);
182 if (error)
183 return (error);
184 if (pcbp != NULL)
185 return (EISCONN);
186 return (ng_attach_cntl(so));
187 }
188
189 static void
190 ngc_detach(struct socket *so)
191 {
192 struct ngpcb *const pcbp = sotongpcb(so);
193
194 KASSERT(pcbp != NULL, ("ngc_detach: pcbp == NULL"));
195 ng_detach_common(pcbp, NG_CONTROL);
196 }
197
198 static int
199 ngc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
200 struct mbuf *control, struct thread *td)
201 {
202 struct ngpcb *const pcbp = sotongpcb(so);
203 struct ngsock *const priv = NG_NODE_PRIVATE(pcbp->sockdata->node);
204 struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
205 struct ng_mesg *msg;
206 struct mbuf *m0;
207 item_p item;
208 char *path = NULL;
209 int len, error = 0;
210 struct ng_apply_info apply;
211
212 #ifdef NOTYET
213 if (control && (error = ng_internalize(control, td))) {
214 if (pcbp->sockdata == NULL) {
215 error = ENOTCONN;
216 goto release;
217 }
218 }
219 #else /* NOTYET */
220 if (control) {
221 error = EINVAL;
222 goto release;
223 }
224 #endif /* NOTYET */
225
226 /* Require destination as there may be >= 1 hooks on this node. */
227 if (addr == NULL) {
228 error = EDESTADDRREQ;
229 goto release;
230 }
231
232 /*
233 * Allocate an expendable buffer for the path, chop off
234 * the sockaddr header, and make sure it's NUL terminated.
235 */
236 len = sap->sg_len - 2;
237 path = malloc(len + 1, M_NETGRAPH_PATH, M_WAITOK);
238 bcopy(sap->sg_data, path, len);
239 path[len] = '\0';
240
241 /*
242 * Move the actual message out of mbufs into a linear buffer.
243 * Start by adding up the size of the data. (could use mh_len?)
244 */
245 for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
246 len += m0->m_len;
247
248 /*
249 * Move the data into a linear buffer as well.
250 * Messages are not delivered in mbufs.
251 */
252 msg = malloc(len + 1, M_NETGRAPH_MSG, M_WAITOK);
253 m_copydata(m, 0, len, (char *)msg);
254
255 if (msg->header.version != NG_VERSION) {
256 free(msg, M_NETGRAPH_MSG);
257 error = EINVAL;
258 goto release;
259 }
260
261 /*
262 * Hack alert!
263 * We look into the message and if it mkpeers a node of unknown type, we
264 * try to load it. We need to do this now, in syscall thread, because if
265 * message gets queued and applied later we will get panic.
266 */
267 if (msg->header.typecookie == NGM_GENERIC_COOKIE &&
268 msg->header.cmd == NGM_MKPEER) {
269 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
270
271 if (ng_findtype(mkp->type) == NULL) {
272 char filename[NG_TYPESIZ + 3];
273 int fileid;
274
275 /* Not found, try to load it as a loadable module. */
276 snprintf(filename, sizeof(filename), "ng_%s",
277 mkp->type);
278 error = kern_kldload(curthread, filename, &fileid);
279 if (error != 0) {
280 free(msg, M_NETGRAPH_MSG);
281 goto release;
282 }
283
284 /* See if type has been loaded successfully. */
285 if (ng_findtype(mkp->type) == NULL) {
286 free(msg, M_NETGRAPH_MSG);
287 (void)kern_kldunload(curthread, fileid,
288 LINKER_UNLOAD_NORMAL);
289 error = ENXIO;
290 goto release;
291 }
292 }
293 }
294
295 item = ng_package_msg(msg, M_WAITOK);
296 if ((error = ng_address_path((pcbp->sockdata->node), item, path, 0))
297 != 0) {
298 #ifdef TRACE_MESSAGES
299 printf("ng_address_path: errx=%d\n", error);
300 #endif
301 goto release;
302 }
303
304 #ifdef TRACE_MESSAGES
305 printf("[%x]:<---------[socket]: c=<%d>cmd=%x(%s) f=%x #%d (%s)\n",
306 item->el_dest->nd_ID,
307 msg->header.typecookie,
308 msg->header.cmd,
309 msg->header.cmdstr,
310 msg->header.flags,
311 msg->header.token,
312 item->el_dest->nd_type->name);
313 #endif
314 SAVE_LINE(item);
315 /*
316 * We do not want to return from syscall until the item
317 * is processed by destination node. We register callback
318 * on the item, which will update priv->error when item
319 * was applied.
320 * If ng_snd_item() has queued item, we sleep until
321 * callback wakes us up.
322 */
323 bzero(&apply, sizeof(apply));
324 apply.apply = ng_socket_item_applied;
325 apply.context = priv;
326 item->apply = &apply;
327 priv->error = -1;
328
329 error = ng_snd_item(item, 0);
330
331 mtx_lock(&priv->mtx);
332 if (priv->error == -1)
333 msleep(priv, &priv->mtx, 0, "ngsock", 0);
334 mtx_unlock(&priv->mtx);
335 KASSERT(priv->error != -1,
336 ("ng_socket: priv->error wasn't updated"));
337 error = priv->error;
338
339 release:
340 if (path != NULL)
341 free(path, M_NETGRAPH_PATH);
342 if (control != NULL)
343 m_freem(control);
344 if (m != NULL)
345 m_freem(m);
346 return (error);
347 }
348
349 static int
350 ngc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
351 {
352 struct ngpcb *const pcbp = sotongpcb(so);
353
354 if (pcbp == 0)
355 return (EINVAL);
356 return (ng_bind(nam, pcbp));
357 }
358
359 static int
360 ngc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
361 {
362 /*
363 * At this time refuse to do this.. it used to
364 * do something but it was undocumented and not used.
365 */
366 printf("program tried to connect control socket to remote node\n");
367 return (EINVAL);
368 }
369
370 /***************************************************************
371 Data sockets
372 ***************************************************************/
373
374 static int
375 ngd_attach(struct socket *so, int proto, struct thread *td)
376 {
377 struct ngpcb *const pcbp = sotongpcb(so);
378
379 if (pcbp != NULL)
380 return (EISCONN);
381 return (ng_attach_data(so));
382 }
383
384 static void
385 ngd_detach(struct socket *so)
386 {
387 struct ngpcb *const pcbp = sotongpcb(so);
388
389 KASSERT(pcbp != NULL, ("ngd_detach: pcbp == NULL"));
390 ng_detach_common(pcbp, NG_DATA);
391 }
392
393 static int
394 ngd_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
395 struct mbuf *control, struct thread *td)
396 {
397 struct ngpcb *const pcbp = sotongpcb(so);
398 struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
399 int len, error;
400 hook_p hook = NULL;
401 char hookname[NG_HOOKSIZ];
402
403 if ((pcbp == NULL) || (control != NULL)) {
404 error = EINVAL;
405 goto release;
406 }
407 if (pcbp->sockdata == NULL) {
408 error = ENOTCONN;
409 goto release;
410 }
411
412 if (sap == NULL)
413 len = 0; /* Make compiler happy. */
414 else
415 len = sap->sg_len - 2;
416
417 /*
418 * If the user used any of these ways to not specify an address
419 * then handle specially.
420 */
421 if ((sap == NULL) || (len <= 0) || (*sap->sg_data == '\0')) {
422 if (NG_NODE_NUMHOOKS(pcbp->sockdata->node) != 1) {
423 error = EDESTADDRREQ;
424 goto release;
425 }
426 /*
427 * If exactly one hook exists, just use it.
428 * Special case to allow write(2) to work on an ng_socket.
429 */
430 hook = LIST_FIRST(&pcbp->sockdata->node->nd_hooks);
431 } else {
432 if (len >= NG_HOOKSIZ) {
433 error = EINVAL;
434 goto release;
435 }
436
437 /*
438 * chop off the sockaddr header, and make sure it's NUL
439 * terminated
440 */
441 bcopy(sap->sg_data, hookname, len);
442 hookname[len] = '\0';
443
444 /* Find the correct hook from 'hookname' */
445 hook = ng_findhook(pcbp->sockdata->node, hookname);
446 if (hook == NULL) {
447 error = EHOSTUNREACH;
448 goto release;
449 }
450 }
451
452 /* Send data. */
453 NG_SEND_DATA_FLAGS(error, hook, m, NG_WAITOK);
454
455 release:
456 if (control != NULL)
457 m_freem(control);
458 if (m != NULL)
459 m_freem(m);
460 return (error);
461 }
462
463 static int
464 ngd_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
465 {
466 struct ngpcb *const pcbp = sotongpcb(so);
467
468 if (pcbp == 0)
469 return (EINVAL);
470 return (ng_connect_data(nam, pcbp));
471 }
472
473 /*
474 * Used for both data and control sockets
475 */
476 static int
477 ng_getsockaddr(struct socket *so, struct sockaddr **addr)
478 {
479 struct ngpcb *pcbp;
480 struct sockaddr_ng *sg;
481 int sg_len;
482 int error = 0;
483
484 /* Why isn't sg_data a `char[1]' ? :-( */
485 sg_len = sizeof(struct sockaddr_ng) - sizeof(sg->sg_data) + 1;
486
487 pcbp = sotongpcb(so);
488 if ((pcbp == NULL) || (pcbp->sockdata == NULL))
489 /* XXXGL: can this still happen? */
490 return (EINVAL);
491
492 mtx_lock(&pcbp->sockdata->mtx);
493 if (pcbp->sockdata->node != NULL) {
494 node_p node = pcbp->sockdata->node;
495 int namelen = 0; /* silence compiler! */
496
497 if (NG_NODE_HAS_NAME(node))
498 sg_len += namelen = strlen(NG_NODE_NAME(node));
499
500 sg = malloc(sg_len, M_SONAME, M_WAITOK | M_ZERO);
501
502 if (NG_NODE_HAS_NAME(node))
503 bcopy(NG_NODE_NAME(node), sg->sg_data, namelen);
504
505 sg->sg_len = sg_len;
506 sg->sg_family = AF_NETGRAPH;
507 *addr = (struct sockaddr *)sg;
508 mtx_unlock(&pcbp->sockdata->mtx);
509 } else {
510 mtx_unlock(&pcbp->sockdata->mtx);
511 error = EINVAL;
512 }
513
514 return (error);
515 }
516
517 /*
518 * Attach a socket to it's protocol specific partner.
519 * For a control socket, actually create a netgraph node and attach
520 * to it as well.
521 */
522
523 static int
524 ng_attach_cntl(struct socket *so)
525 {
526 struct ngsock *priv;
527 struct ngpcb *pcbp;
528 int error;
529
530 /* Allocate node private info */
531 priv = malloc(sizeof(*priv), M_NETGRAPH_SOCK, M_WAITOK | M_ZERO);
532
533 /* Setup protocol control block */
534 if ((error = ng_attach_common(so, NG_CONTROL)) != 0) {
535 free(priv, M_NETGRAPH_SOCK);
536 return (error);
537 }
538 pcbp = sotongpcb(so);
539
540 /* Link the pcb the private data. */
541 priv->ctlsock = pcbp;
542 pcbp->sockdata = priv;
543 priv->refs++;
544
545 /* Initialize mutex. */
546 mtx_init(&priv->mtx, "ng_socket", NULL, MTX_DEF);
547
548 /* Make the generic node components */
549 if ((error = ng_make_node_common(&typestruct, &priv->node)) != 0) {
550 free(priv, M_NETGRAPH_SOCK);
551 ng_detach_common(pcbp, NG_CONTROL);
552 return (error);
553 }
554
555 /* Store a hint for netstat(1). */
556 priv->node_id = priv->node->nd_ID;
557
558 /* Link the node and the private data. */
559 NG_NODE_SET_PRIVATE(priv->node, priv);
560 NG_NODE_REF(priv->node);
561 priv->refs++;
562
563 return (0);
564 }
565
566 static int
567 ng_attach_data(struct socket *so)
568 {
569 return (ng_attach_common(so, NG_DATA));
570 }
571
572 /*
573 * Set up a socket protocol control block.
574 * This code is shared between control and data sockets.
575 */
576 static int
577 ng_attach_common(struct socket *so, int type)
578 {
579 struct ngpcb *pcbp;
580 int error;
581
582 /* Standard socket setup stuff. */
583 error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace);
584 if (error)
585 return (error);
586
587 /* Allocate the pcb. */
588 pcbp = malloc(sizeof(struct ngpcb), M_PCB, M_WAITOK | M_ZERO);
589 pcbp->type = type;
590
591 /* Link the pcb and the socket. */
592 so->so_pcb = (caddr_t)pcbp;
593 pcbp->ng_socket = so;
594
595 /* Add the socket to linked list */
596 mtx_lock(&ngsocketlist_mtx);
597 LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
598 mtx_unlock(&ngsocketlist_mtx);
599 return (0);
600 }
601
602 /*
603 * Disassociate the socket from it's protocol specific
604 * partner. If it's attached to a node's private data structure,
605 * then unlink from that too. If we were the last socket attached to it,
606 * then shut down the entire node. Shared code for control and data sockets.
607 */
608 static void
609 ng_detach_common(struct ngpcb *pcbp, int which)
610 {
611 struct ngsock *priv = pcbp->sockdata;
612
613 if (priv != NULL) {
614 mtx_lock(&priv->mtx);
615
616 switch (which) {
617 case NG_CONTROL:
618 priv->ctlsock = NULL;
619 break;
620 case NG_DATA:
621 priv->datasock = NULL;
622 break;
623 default:
624 panic(__func__);
625 }
626 pcbp->sockdata = NULL;
627
628 ng_socket_free_priv(priv);
629 }
630
631 pcbp->ng_socket->so_pcb = NULL;
632 mtx_lock(&ngsocketlist_mtx);
633 LIST_REMOVE(pcbp, socks);
634 mtx_unlock(&ngsocketlist_mtx);
635 free(pcbp, M_PCB);
636 }
637
638 /*
639 * Remove a reference from node private data.
640 */
641 static void
642 ng_socket_free_priv(struct ngsock *priv)
643 {
644 mtx_assert(&priv->mtx, MA_OWNED);
645
646 priv->refs--;
647
648 if (priv->refs == 0) {
649 mtx_destroy(&priv->mtx);
650 free(priv, M_NETGRAPH_SOCK);
651 return;
652 }
653
654 if ((priv->refs == 1) && (priv->node != NULL)) {
655 node_p node = priv->node;
656
657 priv->node = NULL;
658 mtx_unlock(&priv->mtx);
659 NG_NODE_UNREF(node);
660 ng_rmnode_self(node);
661 } else
662 mtx_unlock(&priv->mtx);
663 }
664
665 #ifdef NOTYET
666 /*
667 * File descriptors can be passed into an AF_NETGRAPH socket.
668 * Note, that file descriptors cannot be passed OUT.
669 * Only character device descriptors are accepted.
670 * Character devices are useful to connect a graph to a device,
671 * which after all is the purpose of this whole system.
672 */
673 static int
674 ng_internalize(struct mbuf *control, struct thread *td)
675 {
676 const struct cmsghdr *cm = mtod(control, const struct cmsghdr *);
677 struct file *fp;
678 struct vnode *vn;
679 int oldfds;
680 int fd;
681
682 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET ||
683 cm->cmsg_len != control->m_len) {
684 TRAP_ERROR;
685 return (EINVAL);
686 }
687
688 /* Check there is only one FD. XXX what would more than one signify? */
689 oldfds = ((caddr_t)cm + cm->cmsg_len - (caddr_t)data) / sizeof (int);
690 if (oldfds != 1) {
691 TRAP_ERROR;
692 return (EINVAL);
693 }
694
695 /* Check that the FD given is legit. and change it to a pointer to a
696 * struct file. */
697 fd = CMSG_DATA(cm);
698 if ((error = fget(td, fd, &fp)) != 0)
699 return (error);
700
701 /* Depending on what kind of resource it is, act differently. For
702 * devices, we treat it as a file. For an AF_NETGRAPH socket,
703 * shortcut straight to the node. */
704 switch (fp->f_type) {
705 case DTYPE_VNODE:
706 vn = fp->f_data;
707 if (vn && (vn->v_type == VCHR)) {
708 /* for a VCHR, actually reference the FILE */
709 fhold(fp);
710 /* XXX then what :) */
711 /* how to pass on to other modules? */
712 } else {
713 fdrop(fp, td);
714 TRAP_ERROR;
715 return (EINVAL);
716 }
717 break;
718 default:
719 fdrop(fp, td);
720 TRAP_ERROR;
721 return (EINVAL);
722 }
723 fdrop(fp, td);
724 return (0);
725 }
726 #endif /* NOTYET */
727
728 /*
729 * Connect the data socket to a named control socket node.
730 */
731 static int
732 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
733 {
734 struct sockaddr_ng *sap;
735 node_p farnode;
736 struct ngsock *priv;
737 int error;
738 item_p item;
739
740 /* If we are already connected, don't do it again. */
741 if (pcbp->sockdata != NULL)
742 return (EISCONN);
743
744 /*
745 * Find the target (victim) and check it doesn't already have
746 * a data socket. Also check it is a 'socket' type node.
747 * Use ng_package_data() and ng_address_path() to do this.
748 */
749
750 sap = (struct sockaddr_ng *) nam;
751 /* The item will hold the node reference. */
752 item = ng_package_data(NULL, NG_WAITOK);
753
754 if ((error = ng_address_path(NULL, item, sap->sg_data, 0)))
755 return (error); /* item is freed on failure */
756
757 /*
758 * Extract node from item and free item. Remember we now have
759 * a reference on the node. The item holds it for us.
760 * when we free the item we release the reference.
761 */
762 farnode = item->el_dest; /* shortcut */
763 if (strcmp(farnode->nd_type->name, NG_SOCKET_NODE_TYPE) != 0) {
764 NG_FREE_ITEM(item); /* drop the reference to the node */
765 return (EINVAL);
766 }
767 priv = NG_NODE_PRIVATE(farnode);
768 if (priv->datasock != NULL) {
769 NG_FREE_ITEM(item); /* drop the reference to the node */
770 return (EADDRINUSE);
771 }
772
773 /*
774 * Link the PCB and the private data struct. and note the extra
775 * reference. Drop the extra reference on the node.
776 */
777 mtx_lock(&priv->mtx);
778 priv->datasock = pcbp;
779 pcbp->sockdata = priv;
780 priv->refs++;
781 mtx_unlock(&priv->mtx);
782 NG_FREE_ITEM(item); /* drop the reference to the node */
783 return (0);
784 }
785
786 /*
787 * Binding a socket means giving the corresponding node a name
788 */
789 static int
790 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
791 {
792 struct ngsock *const priv = pcbp->sockdata;
793 struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
794
795 if (priv == NULL) {
796 TRAP_ERROR;
797 return (EINVAL);
798 }
799 if ((sap->sg_len < 4) || (sap->sg_len > (NG_NODESIZ + 2)) ||
800 (sap->sg_data[0] == '\0') ||
801 (sap->sg_data[sap->sg_len - 3] != '\0')) {
802 TRAP_ERROR;
803 return (EINVAL);
804 }
805 return (ng_name_node(priv->node, sap->sg_data));
806 }
807
808 /***************************************************************
809 Netgraph node
810 ***************************************************************/
811
812 /*
813 * You can only create new nodes from the socket end of things.
814 */
815 static int
816 ngs_constructor(node_p nodep)
817 {
818 return (EINVAL);
819 }
820
821 /*
822 * We allow any hook to be connected to the node.
823 * There is no per-hook private information though.
824 */
825 static int
826 ngs_newhook(node_p node, hook_p hook, const char *name)
827 {
828 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
829 return (0);
830 }
831
832 /*
833 * If only one hook, allow read(2) and write(2) to work.
834 */
835 static int
836 ngs_connect(hook_p hook)
837 {
838 node_p node = NG_HOOK_NODE(hook);
839 struct ngsock *priv = NG_NODE_PRIVATE(node);
840
841 if ((priv->datasock) && (priv->datasock->ng_socket)) {
842 if (NG_NODE_NUMHOOKS(node) == 1)
843 priv->datasock->ng_socket->so_state |= SS_ISCONNECTED;
844 else
845 priv->datasock->ng_socket->so_state &= ~SS_ISCONNECTED;
846 }
847 return (0);
848 }
849
850 /*
851 * Incoming messages get passed up to the control socket.
852 * Unless they are for us specifically (socket_type)
853 */
854 static int
855 ngs_rcvmsg(node_p node, item_p item, hook_p lasthook)
856 {
857 struct ngsock *const priv = NG_NODE_PRIVATE(node);
858 struct ngpcb *pcbp;
859 struct socket *so;
860 struct sockaddr_ng addr;
861 struct ng_mesg *msg;
862 struct mbuf *m;
863 ng_ID_t retaddr = NGI_RETADDR(item);
864 int addrlen;
865 int error = 0;
866
867 NGI_GET_MSG(item, msg);
868 NG_FREE_ITEM(item);
869
870 /*
871 * Grab priv->mtx here to prevent destroying of control socket
872 * after checking that priv->ctlsock is not NULL.
873 */
874 mtx_lock(&priv->mtx);
875 pcbp = priv->ctlsock;
876
877 /*
878 * Only allow mesgs to be passed if we have the control socket.
879 * Data sockets can only support the generic messages.
880 */
881 if (pcbp == NULL) {
882 mtx_unlock(&priv->mtx);
883 TRAP_ERROR;
884 NG_FREE_MSG(msg);
885 return (EINVAL);
886 }
887 so = pcbp->ng_socket;
888 SOCKBUF_LOCK(&so->so_rcv);
889
890 /* As long as the race is handled, priv->mtx may be unlocked now. */
891 mtx_unlock(&priv->mtx);
892
893 #ifdef TRACE_MESSAGES
894 printf("[%x]:---------->[socket]: c=<%d>cmd=%x(%s) f=%x #%d\n",
895 retaddr,
896 msg->header.typecookie,
897 msg->header.cmd,
898 msg->header.cmdstr,
899 msg->header.flags,
900 msg->header.token);
901 #endif
902
903 if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
904 switch (msg->header.cmd) {
905 case NGM_SOCK_CMD_NOLINGER:
906 priv->flags |= NGS_FLAG_NOLINGER;
907 break;
908 case NGM_SOCK_CMD_LINGER:
909 priv->flags &= ~NGS_FLAG_NOLINGER;
910 break;
911 default:
912 error = EINVAL; /* unknown command */
913 }
914 SOCKBUF_UNLOCK(&so->so_rcv);
915
916 /* Free the message and return. */
917 NG_FREE_MSG(msg);
918 return (error);
919 }
920
921 /* Get the return address into a sockaddr. */
922 bzero(&addr, sizeof(addr));
923 addr.sg_len = sizeof(addr);
924 addr.sg_family = AF_NETGRAPH;
925 addrlen = snprintf((char *)&addr.sg_data, sizeof(addr.sg_data),
926 "[%x]:", retaddr);
927 if (addrlen < 0 || addrlen > sizeof(addr.sg_data)) {
928 SOCKBUF_UNLOCK(&so->so_rcv);
929 printf("%s: snprintf([%x]) failed - %d\n", __func__, retaddr,
930 addrlen);
931 NG_FREE_MSG(msg);
932 return (EINVAL);
933 }
934
935 /* Copy the message itself into an mbuf chain. */
936 m = m_devget((caddr_t)msg, sizeof(struct ng_mesg) + msg->header.arglen,
937 0, NULL, NULL);
938
939 /*
940 * Here we free the message. We need to do that
941 * regardless of whether we got mbufs.
942 */
943 NG_FREE_MSG(msg);
944
945 if (m == NULL) {
946 SOCKBUF_UNLOCK(&so->so_rcv);
947 TRAP_ERROR;
948 return (ENOBUFS);
949 }
950
951 /* Send it up to the socket. */
952 if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)&addr, m,
953 NULL) == 0) {
954 SOCKBUF_UNLOCK(&so->so_rcv);
955 TRAP_ERROR;
956 m_freem(m);
957 return (ENOBUFS);
958 }
959 sorwakeup_locked(so);
960
961 return (error);
962 }
963
964 /*
965 * Receive data on a hook
966 */
967 static int
968 ngs_rcvdata(hook_p hook, item_p item)
969 {
970 struct ngsock *const priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
971 struct ngpcb *const pcbp = priv->datasock;
972 struct socket *so;
973 struct sockaddr_ng *addr;
974 char *addrbuf[NG_HOOKSIZ + 4];
975 int addrlen;
976 struct mbuf *m;
977
978 NGI_GET_M(item, m);
979 NG_FREE_ITEM(item);
980
981 /* If there is no data socket, black-hole it. */
982 if (pcbp == NULL) {
983 NG_FREE_M(m);
984 return (0);
985 }
986 so = pcbp->ng_socket;
987
988 /* Get the return address into a sockaddr. */
989 addrlen = strlen(NG_HOOK_NAME(hook)); /* <= NG_HOOKSIZ - 1 */
990 addr = (struct sockaddr_ng *) addrbuf;
991 addr->sg_len = addrlen + 3;
992 addr->sg_family = AF_NETGRAPH;
993 bcopy(NG_HOOK_NAME(hook), addr->sg_data, addrlen);
994 addr->sg_data[addrlen] = '\0';
995
996 /* Try to tell the socket which hook it came in on. */
997 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)addr, m, NULL) == 0) {
998 m_freem(m);
999 TRAP_ERROR;
1000 return (ENOBUFS);
1001 }
1002 sorwakeup(so);
1003 return (0);
1004 }
1005
1006 /*
1007 * Hook disconnection
1008 *
1009 * For this type, removal of the last link destroys the node
1010 * if the NOLINGER flag is set.
1011 */
1012 static int
1013 ngs_disconnect(hook_p hook)
1014 {
1015 node_p node = NG_HOOK_NODE(hook);
1016 struct ngsock *const priv = NG_NODE_PRIVATE(node);
1017
1018 if ((priv->datasock) && (priv->datasock->ng_socket)) {
1019 if (NG_NODE_NUMHOOKS(node) == 1)
1020 priv->datasock->ng_socket->so_state |= SS_ISCONNECTED;
1021 else
1022 priv->datasock->ng_socket->so_state &= ~SS_ISCONNECTED;
1023 }
1024
1025 if ((priv->flags & NGS_FLAG_NOLINGER) &&
1026 (NG_NODE_NUMHOOKS(node) == 0) && (NG_NODE_IS_VALID(node)))
1027 ng_rmnode_self(node);
1028
1029 return (0);
1030 }
1031
1032 /*
1033 * Do local shutdown processing.
1034 * In this case, that involves making sure the socket
1035 * knows we should be shutting down.
1036 */
1037 static int
1038 ngs_shutdown(node_p node)
1039 {
1040 struct ngsock *const priv = NG_NODE_PRIVATE(node);
1041 struct ngpcb *dpcbp, *pcbp;
1042
1043 mtx_lock(&priv->mtx);
1044 dpcbp = priv->datasock;
1045 pcbp = priv->ctlsock;
1046
1047 if (dpcbp != NULL)
1048 soisdisconnected(dpcbp->ng_socket);
1049
1050 if (pcbp != NULL)
1051 soisdisconnected(pcbp->ng_socket);
1052
1053 priv->node = NULL;
1054 NG_NODE_SET_PRIVATE(node, NULL);
1055 ng_socket_free_priv(priv);
1056
1057 NG_NODE_UNREF(node);
1058 return (0);
1059 }
1060
1061 static void
1062 ng_socket_item_applied(void *context, int error)
1063 {
1064 struct ngsock *const priv = (struct ngsock *)context;
1065
1066 mtx_lock(&priv->mtx);
1067 priv->error = error;
1068 wakeup(priv);
1069 mtx_unlock(&priv->mtx);
1070
1071 }
1072
1073 static int
1074 dummy_disconnect(struct socket *so)
1075 {
1076 return (0);
1077 }
1078 /*
1079 * Control and data socket type descriptors
1080 *
1081 * XXXRW: Perhaps _close should do something?
1082 */
1083
1084 static struct pr_usrreqs ngc_usrreqs = {
1085 .pru_abort = NULL,
1086 .pru_attach = ngc_attach,
1087 .pru_bind = ngc_bind,
1088 .pru_connect = ngc_connect,
1089 .pru_detach = ngc_detach,
1090 .pru_disconnect = dummy_disconnect,
1091 .pru_peeraddr = NULL,
1092 .pru_send = ngc_send,
1093 .pru_shutdown = NULL,
1094 .pru_sockaddr = ng_getsockaddr,
1095 .pru_close = NULL,
1096 };
1097
1098 static struct pr_usrreqs ngd_usrreqs = {
1099 .pru_abort = NULL,
1100 .pru_attach = ngd_attach,
1101 .pru_bind = NULL,
1102 .pru_connect = ngd_connect,
1103 .pru_detach = ngd_detach,
1104 .pru_disconnect = dummy_disconnect,
1105 .pru_peeraddr = NULL,
1106 .pru_send = ngd_send,
1107 .pru_shutdown = NULL,
1108 .pru_sockaddr = ng_getsockaddr,
1109 .pru_close = NULL,
1110 };
1111
1112 /*
1113 * Definitions of protocols supported in the NETGRAPH domain.
1114 */
1115
1116 extern struct domain ngdomain; /* stop compiler warnings */
1117
1118 static struct protosw ngsw[] = {
1119 {
1120 .pr_type = SOCK_DGRAM,
1121 .pr_domain = &ngdomain,
1122 .pr_protocol = NG_CONTROL,
1123 .pr_flags = PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
1124 .pr_usrreqs = &ngc_usrreqs
1125 },
1126 {
1127 .pr_type = SOCK_DGRAM,
1128 .pr_domain = &ngdomain,
1129 .pr_protocol = NG_DATA,
1130 .pr_flags = PR_ATOMIC | PR_ADDR,
1131 .pr_usrreqs = &ngd_usrreqs
1132 }
1133 };
1134
1135 struct domain ngdomain = {
1136 .dom_family = AF_NETGRAPH,
1137 .dom_name = "netgraph",
1138 .dom_protosw = ngsw,
1139 .dom_protoswNPROTOSW = &ngsw[sizeof(ngsw) / sizeof(ngsw[0])]
1140 };
1141
1142 /*
1143 * Handle loading and unloading for this node type.
1144 * This is to handle auxiliary linkages (e.g protocol domain addition).
1145 */
1146 static int
1147 ngs_mod_event(module_t mod, int event, void *data)
1148 {
1149 int error = 0;
1150
1151 switch (event) {
1152 case MOD_LOAD:
1153 mtx_init(&ngsocketlist_mtx, "ng_socketlist", NULL, MTX_DEF);
1154 break;
1155 case MOD_UNLOAD:
1156 /* Ensure there are no open netgraph sockets. */
1157 if (!LIST_EMPTY(&ngsocklist)) {
1158 error = EBUSY;
1159 break;
1160 }
1161 #ifdef NOTYET
1162 /* Unregister protocol domain XXX can't do this yet.. */
1163 #endif
1164 error = EBUSY;
1165 break;
1166 default:
1167 error = EOPNOTSUPP;
1168 break;
1169 }
1170 return (error);
1171 }
1172
1173 VNET_DOMAIN_SET(ng);
1174
1175 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, 0, AF_NETGRAPH, "");
1176 SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW, 0, "DATA");
1177 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, 0, NG_DATA, "");
1178 SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW, 0, "CONTROL");
1179 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, 0, NG_CONTROL, "");
1180
Cache object: 08b4eb0893a651dabdf4324b8e9ae84e
|