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 * $Whistle: ng_socket.c,v 1.28 1999/11/01 09:24:52 julian Exp $
40 */
41
42 /*
43 * Netgraph socket nodes
44 *
45 * There are two types of netgraph sockets, control and data.
46 * Control sockets have a netgraph node, but data sockets are
47 * parasitic on control sockets, and have no node of their own.
48 */
49
50 #include <sys/param.h>
51 #include <sys/domain.h>
52 #include <sys/hash.h>
53 #include <sys/kernel.h>
54 #include <sys/linker.h>
55 #include <sys/lock.h>
56 #include <sys/malloc.h>
57 #include <sys/mbuf.h>
58 #include <sys/mutex.h>
59 #include <sys/proc.h>
60 #include <sys/epoch.h>
61 #include <sys/priv.h>
62 #include <sys/protosw.h>
63 #include <sys/queue.h>
64 #include <sys/socket.h>
65 #include <sys/socketvar.h>
66 #include <sys/syscallsubr.h>
67 #include <sys/sysctl.h>
68
69 #include <net/vnet.h>
70
71 #include <netgraph/ng_message.h>
72 #include <netgraph/netgraph.h>
73 #include <netgraph/ng_socketvar.h>
74 #include <netgraph/ng_socket.h>
75
76 #ifdef NG_SEPARATE_MALLOC
77 static MALLOC_DEFINE(M_NETGRAPH_PATH, "netgraph_path", "netgraph path info");
78 static MALLOC_DEFINE(M_NETGRAPH_SOCK, "netgraph_sock", "netgraph socket info");
79 #else
80 #define M_NETGRAPH_PATH M_NETGRAPH
81 #define M_NETGRAPH_SOCK M_NETGRAPH
82 #endif
83
84 /*
85 * It's Ascii-art time!
86 * +-------------+ +-------------+
87 * |socket (ctl)| |socket (data)|
88 * +-------------+ +-------------+
89 * ^ ^
90 * | |
91 * v v
92 * +-----------+ +-----------+
93 * |pcb (ctl)| |pcb (data)|
94 * +-----------+ +-----------+
95 * ^ ^
96 * | |
97 * v v
98 * +--------------------------+
99 * | Socket type private |
100 * | data |
101 * +--------------------------+
102 * ^
103 * |
104 * v
105 * +----------------+
106 * | struct ng_node |
107 * +----------------+
108 */
109
110 /* Netgraph node methods */
111 static ng_constructor_t ngs_constructor;
112 static ng_rcvmsg_t ngs_rcvmsg;
113 static ng_shutdown_t ngs_shutdown;
114 static ng_newhook_t ngs_newhook;
115 static ng_connect_t ngs_connect;
116 static ng_findhook_t ngs_findhook;
117 static ng_rcvdata_t ngs_rcvdata;
118 static ng_disconnect_t ngs_disconnect;
119
120 /* Internal methods */
121 static int ng_attach_data(struct socket *so);
122 static int ng_attach_cntl(struct socket *so);
123 static int ng_attach_common(struct socket *so, int type);
124 static void ng_detach_common(struct ngpcb *pcbp, int type);
125 static void ng_socket_free_priv(struct ngsock *priv);
126 static int ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp);
127 static int ng_bind(struct sockaddr *nam, struct ngpcb *pcbp);
128
129 static int ngs_mod_event(module_t mod, int event, void *data);
130 static void ng_socket_item_applied(void *context, int error);
131
132 /* Netgraph type descriptor */
133 static struct ng_type typestruct = {
134 .version = NG_ABI_VERSION,
135 .name = NG_SOCKET_NODE_TYPE,
136 .mod_event = ngs_mod_event,
137 .constructor = ngs_constructor,
138 .rcvmsg = ngs_rcvmsg,
139 .shutdown = ngs_shutdown,
140 .newhook = ngs_newhook,
141 .connect = ngs_connect,
142 .findhook = ngs_findhook,
143 .rcvdata = ngs_rcvdata,
144 .disconnect = ngs_disconnect,
145 };
146 NETGRAPH_INIT_ORDERED(socket, &typestruct, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);
147
148 /* Buffer space */
149 static u_long ngpdg_sendspace = 20 * 1024; /* really max datagram size */
150 SYSCTL_ULONG(_net_graph, OID_AUTO, maxdgram, CTLFLAG_RW,
151 &ngpdg_sendspace , 0, "Maximum outgoing Netgraph datagram size");
152 static u_long ngpdg_recvspace = 20 * 1024;
153 SYSCTL_ULONG(_net_graph, OID_AUTO, recvspace, CTLFLAG_RW,
154 &ngpdg_recvspace , 0, "Maximum space for incoming Netgraph datagrams");
155
156 /* List of all sockets (for netstat -f netgraph) */
157 static LIST_HEAD(, ngpcb) ngsocklist;
158
159 static struct mtx ngsocketlist_mtx;
160
161 #define sotongpcb(so) ((struct ngpcb *)(so)->so_pcb)
162
163 /* If getting unexplained errors returned, set this to "kdb_enter("X"); */
164 #ifndef TRAP_ERROR
165 #define TRAP_ERROR
166 #endif
167
168 struct hookpriv {
169 LIST_ENTRY(hookpriv) next;
170 hook_p hook;
171 };
172 LIST_HEAD(ngshash, hookpriv);
173
174 /* Per-node private data */
175 struct ngsock {
176 struct ng_node *node; /* the associated netgraph node */
177 struct ngpcb *datasock; /* optional data socket */
178 struct ngpcb *ctlsock; /* optional control socket */
179 struct ngshash *hash; /* hash for hook names */
180 u_long hmask; /* hash mask */
181 int flags;
182 int refs;
183 struct mtx mtx; /* mtx to wait on */
184 int error; /* place to store error */
185 };
186
187 #define NGS_FLAG_NOLINGER 1 /* close with last hook */
188
189 /***************************************************************
190 Control sockets
191 ***************************************************************/
192
193 static int
ngc_attach(struct socket * so,int proto,struct thread * td)194 ngc_attach(struct socket *so, int proto, struct thread *td)
195 {
196 struct ngpcb *const pcbp = sotongpcb(so);
197 int error;
198
199 error = priv_check(td, PRIV_NETGRAPH_CONTROL);
200 if (error)
201 return (error);
202 if (pcbp != NULL)
203 return (EISCONN);
204 return (ng_attach_cntl(so));
205 }
206
207 static void
ngc_detach(struct socket * so)208 ngc_detach(struct socket *so)
209 {
210 struct ngpcb *const pcbp = sotongpcb(so);
211
212 KASSERT(pcbp != NULL, ("ngc_detach: pcbp == NULL"));
213 ng_detach_common(pcbp, NG_CONTROL);
214 }
215
216 static int
ngc_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct thread * td)217 ngc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
218 struct mbuf *control, struct thread *td)
219 {
220 struct ngpcb *const pcbp = sotongpcb(so);
221 struct ngsock *const priv = NG_NODE_PRIVATE(pcbp->sockdata->node);
222 struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
223 struct ng_mesg *msg;
224 struct mbuf *m0;
225 item_p item;
226 char *path = NULL;
227 int len, error = 0;
228 struct ng_apply_info apply;
229
230 if (control) {
231 error = EINVAL;
232 goto release;
233 }
234
235 /* Require destination as there may be >= 1 hooks on this node. */
236 if (addr == NULL) {
237 error = EDESTADDRREQ;
238 goto release;
239 }
240
241 if (sap->sg_len > NG_NODESIZ + offsetof(struct sockaddr_ng, sg_data)) {
242 error = EINVAL;
243 goto release;
244 }
245
246 /*
247 * Allocate an expendable buffer for the path, chop off
248 * the sockaddr header, and make sure it's NUL terminated.
249 */
250 len = sap->sg_len - offsetof(struct sockaddr_ng, sg_data);
251 path = malloc(len + 1, M_NETGRAPH_PATH, M_WAITOK);
252 bcopy(sap->sg_data, path, len);
253 path[len] = '\0';
254
255 /*
256 * Move the actual message out of mbufs into a linear buffer.
257 * Start by adding up the size of the data. (could use mh_len?)
258 */
259 for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
260 len += m0->m_len;
261
262 /*
263 * Move the data into a linear buffer as well.
264 * Messages are not delivered in mbufs.
265 */
266 msg = malloc(len + 1, M_NETGRAPH_MSG, M_WAITOK);
267 m_copydata(m, 0, len, (char *)msg);
268
269 if (msg->header.version != NG_VERSION) {
270 free(msg, M_NETGRAPH_MSG);
271 error = EINVAL;
272 goto release;
273 }
274
275 /*
276 * Hack alert!
277 * We look into the message and if it mkpeers a node of unknown type, we
278 * try to load it. We need to do this now, in syscall thread, because if
279 * message gets queued and applied later we will get panic.
280 */
281 if (msg->header.typecookie == NGM_GENERIC_COOKIE &&
282 msg->header.cmd == NGM_MKPEER) {
283 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
284
285 if (ng_findtype(mkp->type) == NULL) {
286 char filename[NG_TYPESIZ + 3];
287 int fileid;
288 bool loaded;
289
290 /* Not found, try to load it as a loadable module. */
291 snprintf(filename, sizeof(filename), "ng_%s",
292 mkp->type);
293 error = kern_kldload(curthread, filename, &fileid);
294 loaded = (error == 0);
295 if (error == EEXIST)
296 error = 0;
297 if (error != 0) {
298 free(msg, M_NETGRAPH_MSG);
299 goto release;
300 }
301
302 /* See if type has been loaded successfully. */
303 if (ng_findtype(mkp->type) == NULL) {
304 free(msg, M_NETGRAPH_MSG);
305 if (loaded)
306 (void)kern_kldunload(curthread, fileid,
307 LINKER_UNLOAD_NORMAL);
308 error = ENXIO;
309 goto release;
310 }
311 }
312 }
313
314 item = ng_package_msg(msg, NG_WAITOK);
315 if ((error = ng_address_path((pcbp->sockdata->node), item, path, 0))
316 != 0) {
317 #ifdef TRACE_MESSAGES
318 printf("ng_address_path: errx=%d\n", error);
319 #endif
320 goto release;
321 }
322
323 #ifdef TRACE_MESSAGES
324 printf("[%x]:<---------[socket]: c=<%d>cmd=%x(%s) f=%x #%d (%s)\n",
325 item->el_dest->nd_ID,
326 msg->header.typecookie,
327 msg->header.cmd,
328 msg->header.cmdstr,
329 msg->header.flags,
330 msg->header.token,
331 item->el_dest->nd_type->name);
332 #endif
333 SAVE_LINE(item);
334 /*
335 * We do not want to return from syscall until the item
336 * is processed by destination node. We register callback
337 * on the item, which will update priv->error when item
338 * was applied.
339 * If ng_snd_item() has queued item, we sleep until
340 * callback wakes us up.
341 */
342 bzero(&apply, sizeof(apply));
343 apply.apply = ng_socket_item_applied;
344 apply.context = priv;
345 item->apply = &apply;
346 priv->error = -1;
347
348 error = ng_snd_item(item, 0);
349
350 mtx_lock(&priv->mtx);
351 if (priv->error == -1)
352 msleep(priv, &priv->mtx, 0, "ngsock", 0);
353 mtx_unlock(&priv->mtx);
354 KASSERT(priv->error != -1,
355 ("ng_socket: priv->error wasn't updated"));
356 error = priv->error;
357
358 release:
359 if (path != NULL)
360 free(path, M_NETGRAPH_PATH);
361 if (control != NULL)
362 m_freem(control);
363 if (m != NULL)
364 m_freem(m);
365 return (error);
366 }
367
368 static int
ngc_bind(struct socket * so,struct sockaddr * nam,struct thread * td)369 ngc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
370 {
371 struct ngpcb *const pcbp = sotongpcb(so);
372
373 if (pcbp == NULL)
374 return (EINVAL);
375 return (ng_bind(nam, pcbp));
376 }
377
378 static int
ngc_connect(struct socket * so,struct sockaddr * nam,struct thread * td)379 ngc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
380 {
381 /*
382 * At this time refuse to do this.. it used to
383 * do something but it was undocumented and not used.
384 */
385 printf("program tried to connect control socket to remote node\n");
386 return (EINVAL);
387 }
388
389 /***************************************************************
390 Data sockets
391 ***************************************************************/
392
393 static int
ngd_attach(struct socket * so,int proto,struct thread * td)394 ngd_attach(struct socket *so, int proto, struct thread *td)
395 {
396 struct ngpcb *const pcbp = sotongpcb(so);
397
398 if (pcbp != NULL)
399 return (EISCONN);
400 return (ng_attach_data(so));
401 }
402
403 static void
ngd_detach(struct socket * so)404 ngd_detach(struct socket *so)
405 {
406 struct ngpcb *const pcbp = sotongpcb(so);
407
408 KASSERT(pcbp != NULL, ("ngd_detach: pcbp == NULL"));
409 ng_detach_common(pcbp, NG_DATA);
410 }
411
412 static int
ngd_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct thread * td)413 ngd_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
414 struct mbuf *control, struct thread *td)
415 {
416 struct epoch_tracker et;
417 struct ngpcb *const pcbp = sotongpcb(so);
418 struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
419 int len, error;
420 hook_p hook = NULL;
421 item_p item;
422 char hookname[NG_HOOKSIZ];
423
424 if ((pcbp == NULL) || (control != NULL)) {
425 error = EINVAL;
426 goto release;
427 }
428 if (pcbp->sockdata == NULL) {
429 error = ENOTCONN;
430 goto release;
431 }
432
433 if (sap == NULL) {
434 len = 0; /* Make compiler happy. */
435 } else {
436 if (sap->sg_len > NG_NODESIZ +
437 offsetof(struct sockaddr_ng, sg_data)) {
438 error = EINVAL;
439 goto release;
440 }
441 len = sap->sg_len - offsetof(struct sockaddr_ng, sg_data);
442 }
443
444 /*
445 * If the user used any of these ways to not specify an address
446 * then handle specially.
447 */
448 if ((sap == NULL) || (len <= 0) || (*sap->sg_data == '\0')) {
449 if (NG_NODE_NUMHOOKS(pcbp->sockdata->node) != 1) {
450 error = EDESTADDRREQ;
451 goto release;
452 }
453 /*
454 * If exactly one hook exists, just use it.
455 * Special case to allow write(2) to work on an ng_socket.
456 */
457 hook = LIST_FIRST(&pcbp->sockdata->node->nd_hooks);
458 } else {
459 if (len >= NG_HOOKSIZ) {
460 error = EINVAL;
461 goto release;
462 }
463
464 /*
465 * chop off the sockaddr header, and make sure it's NUL
466 * terminated
467 */
468 bcopy(sap->sg_data, hookname, len);
469 hookname[len] = '\0';
470
471 /* Find the correct hook from 'hookname' */
472 hook = ng_findhook(pcbp->sockdata->node, hookname);
473 if (hook == NULL) {
474 error = EHOSTUNREACH;
475 goto release;
476 }
477 }
478
479 /* Send data. */
480 item = ng_package_data(m, NG_WAITOK);
481 m = NULL;
482 NET_EPOCH_ENTER(et);
483 NG_FWD_ITEM_HOOK(error, item, hook);
484 NET_EPOCH_EXIT(et);
485
486 release:
487 if (control != NULL)
488 m_freem(control);
489 if (m != NULL)
490 m_freem(m);
491 return (error);
492 }
493
494 static int
ngd_connect(struct socket * so,struct sockaddr * nam,struct thread * td)495 ngd_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
496 {
497 struct ngpcb *const pcbp = sotongpcb(so);
498
499 if (pcbp == NULL)
500 return (EINVAL);
501 return (ng_connect_data(nam, pcbp));
502 }
503
504 /*
505 * Used for both data and control sockets
506 */
507 static int
ng_getsockaddr(struct socket * so,struct sockaddr * sa)508 ng_getsockaddr(struct socket *so, struct sockaddr *sa)
509 {
510 struct sockaddr_ng *sg = (struct sockaddr_ng *)sa;
511 struct ngpcb *pcbp;
512 int error = 0;
513
514 pcbp = sotongpcb(so);
515 if ((pcbp == NULL) || (pcbp->sockdata == NULL))
516 /* XXXGL: can this still happen? */
517 return (EINVAL);
518
519 *sg = (struct sockaddr_ng ){
520 .sg_len = sizeof(struct sockaddr_ng),
521 .sg_family = AF_NETGRAPH,
522 };
523
524 mtx_lock(&pcbp->sockdata->mtx);
525 if (pcbp->sockdata->node != NULL) {
526 node_p node = pcbp->sockdata->node;
527
528 if (NG_NODE_HAS_NAME(node))
529 bcopy(NG_NODE_NAME(node), sg->sg_data,
530 strlen(NG_NODE_NAME(node)));
531 else
532 snprintf(sg->sg_data, sizeof(sg->sg_data), "[%x]",
533 ng_node2ID(node));
534 } else
535 error = EINVAL;
536 mtx_unlock(&pcbp->sockdata->mtx);
537
538 return (error);
539 }
540
541 /*
542 * Attach a socket to it's protocol specific partner.
543 * For a control socket, actually create a netgraph node and attach
544 * to it as well.
545 */
546
547 static int
ng_attach_cntl(struct socket * so)548 ng_attach_cntl(struct socket *so)
549 {
550 struct ngsock *priv;
551 struct ngpcb *pcbp;
552 node_p node;
553 int error;
554
555 /* Setup protocol control block */
556 if ((error = ng_attach_common(so, NG_CONTROL)) != 0)
557 return (error);
558 pcbp = sotongpcb(so);
559
560 /* Make the generic node components */
561 if ((error = ng_make_node_common(&typestruct, &node)) != 0) {
562 ng_detach_common(pcbp, NG_CONTROL);
563 return (error);
564 }
565
566 /*
567 * Allocate node private info and hash. We start
568 * with 16 hash entries, however we may grow later
569 * in ngs_newhook(). We can't predict how much hooks
570 * does this node plan to have.
571 */
572 priv = malloc(sizeof(*priv), M_NETGRAPH_SOCK, M_WAITOK | M_ZERO);
573 priv->hash = hashinit(16, M_NETGRAPH_SOCK, &priv->hmask);
574
575 /* Initialize mutex. */
576 mtx_init(&priv->mtx, "ng_socket", NULL, MTX_DEF);
577
578 /* Link the pcb the private data. */
579 priv->ctlsock = pcbp;
580 pcbp->sockdata = priv;
581 priv->refs++;
582 priv->node = node;
583 pcbp->node_id = node->nd_ID; /* hint for netstat(1) */
584
585 /* Link the node and the private data. */
586 NG_NODE_SET_PRIVATE(priv->node, priv);
587 NG_NODE_REF(priv->node);
588 priv->refs++;
589
590 return (0);
591 }
592
593 static int
ng_attach_data(struct socket * so)594 ng_attach_data(struct socket *so)
595 {
596 return (ng_attach_common(so, NG_DATA));
597 }
598
599 /*
600 * Set up a socket protocol control block.
601 * This code is shared between control and data sockets.
602 */
603 static int
ng_attach_common(struct socket * so,int type)604 ng_attach_common(struct socket *so, int type)
605 {
606 struct ngpcb *pcbp;
607 int error;
608
609 /* Standard socket setup stuff. */
610 error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace);
611 if (error)
612 return (error);
613
614 /* Allocate the pcb. */
615 pcbp = malloc(sizeof(struct ngpcb), M_PCB, M_WAITOK | M_ZERO);
616 pcbp->type = type;
617
618 /* Link the pcb and the socket. */
619 so->so_pcb = (caddr_t)pcbp;
620 pcbp->ng_socket = so;
621
622 /* Add the socket to linked list */
623 mtx_lock(&ngsocketlist_mtx);
624 LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
625 mtx_unlock(&ngsocketlist_mtx);
626 return (0);
627 }
628
629 /*
630 * Disassociate the socket from it's protocol specific
631 * partner. If it's attached to a node's private data structure,
632 * then unlink from that too. If we were the last socket attached to it,
633 * then shut down the entire node. Shared code for control and data sockets.
634 */
635 static void
ng_detach_common(struct ngpcb * pcbp,int which)636 ng_detach_common(struct ngpcb *pcbp, int which)
637 {
638 struct ngsock *priv = pcbp->sockdata;
639
640 if (priv != NULL) {
641 mtx_lock(&priv->mtx);
642
643 switch (which) {
644 case NG_CONTROL:
645 priv->ctlsock = NULL;
646 break;
647 case NG_DATA:
648 priv->datasock = NULL;
649 break;
650 default:
651 panic("%s", __func__);
652 }
653 pcbp->sockdata = NULL;
654 pcbp->node_id = 0;
655
656 ng_socket_free_priv(priv);
657 }
658
659 pcbp->ng_socket->so_pcb = NULL;
660 mtx_lock(&ngsocketlist_mtx);
661 LIST_REMOVE(pcbp, socks);
662 mtx_unlock(&ngsocketlist_mtx);
663 free(pcbp, M_PCB);
664 }
665
666 /*
667 * Remove a reference from node private data.
668 */
669 static void
ng_socket_free_priv(struct ngsock * priv)670 ng_socket_free_priv(struct ngsock *priv)
671 {
672 mtx_assert(&priv->mtx, MA_OWNED);
673
674 priv->refs--;
675
676 if (priv->refs == 0) {
677 mtx_destroy(&priv->mtx);
678 hashdestroy(priv->hash, M_NETGRAPH_SOCK, priv->hmask);
679 free(priv, M_NETGRAPH_SOCK);
680 return;
681 }
682
683 if ((priv->refs == 1) && (priv->node != NULL)) {
684 node_p node = priv->node;
685
686 priv->node = NULL;
687 mtx_unlock(&priv->mtx);
688 NG_NODE_UNREF(node);
689 ng_rmnode_self(node);
690 } else
691 mtx_unlock(&priv->mtx);
692 }
693
694 /*
695 * Connect the data socket to a named control socket node.
696 */
697 static int
ng_connect_data(struct sockaddr * nam,struct ngpcb * pcbp)698 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
699 {
700 struct sockaddr_ng *sap;
701 node_p farnode;
702 struct ngsock *priv;
703 int error;
704 item_p item;
705
706 /* If we are already connected, don't do it again. */
707 if (pcbp->sockdata != NULL)
708 return (EISCONN);
709
710 /*
711 * Find the target (victim) and check it doesn't already have
712 * a data socket. Also check it is a 'socket' type node.
713 * Use ng_package_data() and ng_address_path() to do this.
714 */
715
716 sap = (struct sockaddr_ng *) nam;
717 /* The item will hold the node reference. */
718 item = ng_package_data(NULL, NG_WAITOK);
719
720 if ((error = ng_address_path(NULL, item, sap->sg_data, 0)))
721 return (error); /* item is freed on failure */
722
723 /*
724 * Extract node from item and free item. Remember we now have
725 * a reference on the node. The item holds it for us.
726 * when we free the item we release the reference.
727 */
728 farnode = item->el_dest; /* shortcut */
729 if (strcmp(farnode->nd_type->name, NG_SOCKET_NODE_TYPE) != 0) {
730 NG_FREE_ITEM(item); /* drop the reference to the node */
731 return (EINVAL);
732 }
733 priv = NG_NODE_PRIVATE(farnode);
734 if (priv->datasock != NULL) {
735 NG_FREE_ITEM(item); /* drop the reference to the node */
736 return (EADDRINUSE);
737 }
738
739 /*
740 * Link the PCB and the private data struct. and note the extra
741 * reference. Drop the extra reference on the node.
742 */
743 mtx_lock(&priv->mtx);
744 priv->datasock = pcbp;
745 pcbp->sockdata = priv;
746 pcbp->node_id = priv->node->nd_ID; /* hint for netstat(1) */
747 priv->refs++;
748 mtx_unlock(&priv->mtx);
749 NG_FREE_ITEM(item); /* drop the reference to the node */
750 return (0);
751 }
752
753 /*
754 * Binding a socket means giving the corresponding node a name
755 */
756 static int
ng_bind(struct sockaddr * nam,struct ngpcb * pcbp)757 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
758 {
759 struct ngsock *const priv = pcbp->sockdata;
760 struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
761
762 if (priv == NULL) {
763 TRAP_ERROR;
764 return (EINVAL);
765 }
766 if ((sap->sg_len < 4) || (sap->sg_len > (NG_NODESIZ + 2)) ||
767 (sap->sg_data[0] == '\0') ||
768 (sap->sg_data[sap->sg_len - 3] != '\0')) {
769 TRAP_ERROR;
770 return (EINVAL);
771 }
772 return (ng_name_node(priv->node, sap->sg_data));
773 }
774
775 /***************************************************************
776 Netgraph node
777 ***************************************************************/
778
779 /*
780 * You can only create new nodes from the socket end of things.
781 */
782 static int
ngs_constructor(node_p nodep)783 ngs_constructor(node_p nodep)
784 {
785 return (EINVAL);
786 }
787
788 static void
ngs_rehash(node_p node)789 ngs_rehash(node_p node)
790 {
791 struct ngsock *priv = NG_NODE_PRIVATE(node);
792 struct ngshash *new;
793 struct hookpriv *hp;
794 hook_p hook;
795 uint32_t h;
796 u_long hmask;
797
798 new = hashinit_flags((priv->hmask + 1) * 2, M_NETGRAPH_SOCK, &hmask,
799 HASH_NOWAIT);
800 if (new == NULL)
801 return;
802
803 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
804 hp = NG_HOOK_PRIVATE(hook);
805 #ifdef INVARIANTS
806 LIST_REMOVE(hp, next);
807 #endif
808 h = hash32_str(NG_HOOK_NAME(hook), HASHINIT) & hmask;
809 LIST_INSERT_HEAD(&new[h], hp, next);
810 }
811
812 hashdestroy(priv->hash, M_NETGRAPH_SOCK, priv->hmask);
813 priv->hash = new;
814 priv->hmask = hmask;
815 }
816
817 /*
818 * We allow any hook to be connected to the node.
819 * There is no per-hook private information though.
820 */
821 static int
ngs_newhook(node_p node,hook_p hook,const char * name)822 ngs_newhook(node_p node, hook_p hook, const char *name)
823 {
824 struct ngsock *const priv = NG_NODE_PRIVATE(node);
825 struct hookpriv *hp;
826 uint32_t h;
827
828 hp = malloc(sizeof(*hp), M_NETGRAPH_SOCK, M_NOWAIT);
829 if (hp == NULL)
830 return (ENOMEM);
831 if (node->nd_numhooks * 2 > priv->hmask)
832 ngs_rehash(node);
833 hp->hook = hook;
834 h = hash32_str(name, HASHINIT) & priv->hmask;
835 LIST_INSERT_HEAD(&priv->hash[h], hp, next);
836 NG_HOOK_SET_PRIVATE(hook, hp);
837
838 return (0);
839 }
840
841 /*
842 * If only one hook, allow read(2) and write(2) to work.
843 */
844 static int
ngs_connect(hook_p hook)845 ngs_connect(hook_p hook)
846 {
847 node_p node = NG_HOOK_NODE(hook);
848 struct ngsock *priv = NG_NODE_PRIVATE(node);
849
850 if ((priv->datasock) && (priv->datasock->ng_socket)) {
851 if (NG_NODE_NUMHOOKS(node) == 1)
852 priv->datasock->ng_socket->so_state |= SS_ISCONNECTED;
853 else
854 priv->datasock->ng_socket->so_state &= ~SS_ISCONNECTED;
855 }
856 return (0);
857 }
858
859 /* Look up hook by name */
860 static hook_p
ngs_findhook(node_p node,const char * name)861 ngs_findhook(node_p node, const char *name)
862 {
863 struct ngsock *priv = NG_NODE_PRIVATE(node);
864 struct hookpriv *hp;
865 uint32_t h;
866
867 /*
868 * Microoptimisation for an ng_socket with
869 * a single hook, which is a common case.
870 */
871 if (node->nd_numhooks == 1) {
872 hook_p hook;
873
874 hook = LIST_FIRST(&node->nd_hooks);
875
876 if (strcmp(NG_HOOK_NAME(hook), name) == 0)
877 return (hook);
878 else
879 return (NULL);
880 }
881
882 h = hash32_str(name, HASHINIT) & priv->hmask;
883
884 LIST_FOREACH(hp, &priv->hash[h], next)
885 if (strcmp(NG_HOOK_NAME(hp->hook), name) == 0)
886 return (hp->hook);
887
888 return (NULL);
889 }
890
891 /*
892 * Incoming messages get passed up to the control socket.
893 * Unless they are for us specifically (socket_type)
894 */
895 static int
ngs_rcvmsg(node_p node,item_p item,hook_p lasthook)896 ngs_rcvmsg(node_p node, item_p item, hook_p lasthook)
897 {
898 struct ngsock *const priv = NG_NODE_PRIVATE(node);
899 struct ngpcb *pcbp;
900 struct socket *so;
901 struct sockaddr_ng addr;
902 struct ng_mesg *msg;
903 struct mbuf *m;
904 ng_ID_t retaddr = NGI_RETADDR(item);
905 int addrlen;
906 int error = 0;
907
908 NGI_GET_MSG(item, msg);
909 NG_FREE_ITEM(item);
910
911 /*
912 * Grab priv->mtx here to prevent destroying of control socket
913 * after checking that priv->ctlsock is not NULL.
914 */
915 mtx_lock(&priv->mtx);
916 pcbp = priv->ctlsock;
917
918 /*
919 * Only allow mesgs to be passed if we have the control socket.
920 * Data sockets can only support the generic messages.
921 */
922 if (pcbp == NULL) {
923 mtx_unlock(&priv->mtx);
924 TRAP_ERROR;
925 NG_FREE_MSG(msg);
926 return (EINVAL);
927 }
928 so = pcbp->ng_socket;
929 SOCKBUF_LOCK(&so->so_rcv);
930
931 /* As long as the race is handled, priv->mtx may be unlocked now. */
932 mtx_unlock(&priv->mtx);
933
934 #ifdef TRACE_MESSAGES
935 printf("[%x]:---------->[socket]: c=<%d>cmd=%x(%s) f=%x #%d\n",
936 retaddr,
937 msg->header.typecookie,
938 msg->header.cmd,
939 msg->header.cmdstr,
940 msg->header.flags,
941 msg->header.token);
942 #endif
943
944 if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
945 switch (msg->header.cmd) {
946 case NGM_SOCK_CMD_NOLINGER:
947 priv->flags |= NGS_FLAG_NOLINGER;
948 break;
949 case NGM_SOCK_CMD_LINGER:
950 priv->flags &= ~NGS_FLAG_NOLINGER;
951 break;
952 default:
953 error = EINVAL; /* unknown command */
954 }
955 SOCKBUF_UNLOCK(&so->so_rcv);
956
957 /* Free the message and return. */
958 NG_FREE_MSG(msg);
959 return (error);
960 }
961
962 /* Get the return address into a sockaddr. */
963 bzero(&addr, sizeof(addr));
964 addr.sg_len = sizeof(addr);
965 addr.sg_family = AF_NETGRAPH;
966 addrlen = snprintf((char *)&addr.sg_data, sizeof(addr.sg_data),
967 "[%x]:", retaddr);
968 if (addrlen < 0 || addrlen > sizeof(addr.sg_data)) {
969 SOCKBUF_UNLOCK(&so->so_rcv);
970 printf("%s: snprintf([%x]) failed - %d\n", __func__, retaddr,
971 addrlen);
972 NG_FREE_MSG(msg);
973 return (EINVAL);
974 }
975
976 /* Copy the message itself into an mbuf chain. */
977 m = m_devget((caddr_t)msg, sizeof(struct ng_mesg) + msg->header.arglen,
978 0, NULL, NULL);
979
980 /*
981 * Here we free the message. We need to do that
982 * regardless of whether we got mbufs.
983 */
984 NG_FREE_MSG(msg);
985
986 if (m == NULL) {
987 SOCKBUF_UNLOCK(&so->so_rcv);
988 TRAP_ERROR;
989 return (ENOBUFS);
990 }
991
992 /* Send it up to the socket. */
993 if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)&addr, m,
994 NULL) == 0) {
995 soroverflow_locked(so);
996 TRAP_ERROR;
997 m_freem(m);
998 return (ENOBUFS);
999 }
1000
1001 /* sorwakeup_locked () releases the lock internally. */
1002 sorwakeup_locked(so);
1003
1004 return (error);
1005 }
1006
1007 /*
1008 * Receive data on a hook
1009 */
1010 static int
ngs_rcvdata(hook_p hook,item_p item)1011 ngs_rcvdata(hook_p hook, item_p item)
1012 {
1013 struct ngsock *const priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
1014 struct ngpcb *const pcbp = priv->datasock;
1015 struct socket *so;
1016 struct sockaddr_ng *addr;
1017 char *addrbuf[NG_HOOKSIZ + 4];
1018 int addrlen;
1019 struct mbuf *m;
1020
1021 NGI_GET_M(item, m);
1022 NG_FREE_ITEM(item);
1023
1024 /* If there is no data socket, black-hole it. */
1025 if (pcbp == NULL) {
1026 NG_FREE_M(m);
1027 return (0);
1028 }
1029 so = pcbp->ng_socket;
1030
1031 /* Get the return address into a sockaddr. */
1032 addrlen = strlen(NG_HOOK_NAME(hook)); /* <= NG_HOOKSIZ - 1 */
1033 addr = (struct sockaddr_ng *) addrbuf;
1034 addr->sg_len = addrlen + 3;
1035 addr->sg_family = AF_NETGRAPH;
1036 bcopy(NG_HOOK_NAME(hook), addr->sg_data, addrlen);
1037 addr->sg_data[addrlen] = '\0';
1038
1039 /* Try to tell the socket which hook it came in on. */
1040 SOCKBUF_LOCK(&so->so_rcv);
1041 if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)addr, m,
1042 NULL) == 0) {
1043 SOCKBUF_UNLOCK(&so->so_rcv);
1044 m_freem(m);
1045 TRAP_ERROR;
1046 return (ENOBUFS);
1047 }
1048
1049 /* sorwakeup_locked () releases the lock internally. */
1050 sorwakeup_locked(so);
1051 return (0);
1052 }
1053
1054 /*
1055 * Hook disconnection
1056 *
1057 * For this type, removal of the last link destroys the node
1058 * if the NOLINGER flag is set.
1059 */
1060 static int
ngs_disconnect(hook_p hook)1061 ngs_disconnect(hook_p hook)
1062 {
1063 node_p node = NG_HOOK_NODE(hook);
1064 struct ngsock *const priv = NG_NODE_PRIVATE(node);
1065 struct hookpriv *hp = NG_HOOK_PRIVATE(hook);
1066
1067 LIST_REMOVE(hp, next);
1068 free(hp, M_NETGRAPH_SOCK);
1069
1070 if ((priv->datasock) && (priv->datasock->ng_socket)) {
1071 if (NG_NODE_NUMHOOKS(node) == 1)
1072 priv->datasock->ng_socket->so_state |= SS_ISCONNECTED;
1073 else
1074 priv->datasock->ng_socket->so_state &= ~SS_ISCONNECTED;
1075 }
1076
1077 if ((priv->flags & NGS_FLAG_NOLINGER) &&
1078 (NG_NODE_NUMHOOKS(node) == 0) && (NG_NODE_IS_VALID(node)))
1079 ng_rmnode_self(node);
1080
1081 return (0);
1082 }
1083
1084 /*
1085 * Do local shutdown processing.
1086 * In this case, that involves making sure the socket
1087 * knows we should be shutting down.
1088 */
1089 static int
ngs_shutdown(node_p node)1090 ngs_shutdown(node_p node)
1091 {
1092 struct ngsock *const priv = NG_NODE_PRIVATE(node);
1093 struct ngpcb *dpcbp, *pcbp;
1094
1095 mtx_lock(&priv->mtx);
1096 dpcbp = priv->datasock;
1097 pcbp = priv->ctlsock;
1098
1099 if (dpcbp != NULL)
1100 soisdisconnected(dpcbp->ng_socket);
1101
1102 if (pcbp != NULL)
1103 soisdisconnected(pcbp->ng_socket);
1104
1105 priv->node = NULL;
1106 NG_NODE_SET_PRIVATE(node, NULL);
1107 ng_socket_free_priv(priv);
1108
1109 NG_NODE_UNREF(node);
1110 return (0);
1111 }
1112
1113 static void
ng_socket_item_applied(void * context,int error)1114 ng_socket_item_applied(void *context, int error)
1115 {
1116 struct ngsock *const priv = (struct ngsock *)context;
1117
1118 mtx_lock(&priv->mtx);
1119 priv->error = error;
1120 wakeup(priv);
1121 mtx_unlock(&priv->mtx);
1122
1123 }
1124
1125 static int
dummy_disconnect(struct socket * so)1126 dummy_disconnect(struct socket *so)
1127 {
1128 return (0);
1129 }
1130
1131 /*
1132 * Definitions of protocols supported in the NETGRAPH domain.
1133 * Control and data socket type descriptors
1134 *
1135 * XXXRW: Perhaps _close should do something?
1136 */
1137 static struct protosw ngcontrol_protosw = {
1138 .pr_type = SOCK_DGRAM,
1139 .pr_protocol = NG_CONTROL,
1140 .pr_flags = PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
1141 .pr_attach = ngc_attach,
1142 .pr_bind = ngc_bind,
1143 .pr_connect = ngc_connect,
1144 .pr_detach = ngc_detach,
1145 .pr_disconnect = dummy_disconnect,
1146 .pr_send = ngc_send,
1147 .pr_sockaddr = ng_getsockaddr,
1148 };
1149 static struct protosw ngdata_protosw = {
1150 .pr_type = SOCK_DGRAM,
1151 .pr_protocol = NG_DATA,
1152 .pr_flags = PR_ATOMIC | PR_ADDR,
1153 .pr_attach = ngd_attach,
1154 .pr_connect = ngd_connect,
1155 .pr_detach = ngd_detach,
1156 .pr_disconnect = dummy_disconnect,
1157 .pr_send = ngd_send,
1158 .pr_sockaddr = ng_getsockaddr,
1159 };
1160
1161 static struct domain ngdomain = {
1162 .dom_family = AF_NETGRAPH,
1163 .dom_name = "netgraph",
1164 .dom_nprotosw = 2,
1165 .dom_protosw = { &ngcontrol_protosw, &ngdata_protosw },
1166 };
1167
1168 /*
1169 * Handle loading and unloading for this node type.
1170 * This is to handle auxiliary linkages (e.g protocol domain addition).
1171 */
1172 static int
ngs_mod_event(module_t mod,int event,void * data)1173 ngs_mod_event(module_t mod, int event, void *data)
1174 {
1175 int error = 0;
1176
1177 switch (event) {
1178 case MOD_LOAD:
1179 mtx_init(&ngsocketlist_mtx, "ng_socketlist", NULL, MTX_DEF);
1180 break;
1181 case MOD_UNLOAD:
1182 /* Ensure there are no open netgraph sockets. */
1183 if (!LIST_EMPTY(&ngsocklist)) {
1184 error = EBUSY;
1185 break;
1186 }
1187 #ifdef NOTYET
1188 /* Unregister protocol domain XXX can't do this yet.. */
1189 #endif
1190 error = EBUSY;
1191 break;
1192 default:
1193 error = EOPNOTSUPP;
1194 break;
1195 }
1196 return (error);
1197 }
1198
1199 DOMAIN_SET(ng);
1200
1201 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, AF_NETGRAPH, "");
1202 static SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1203 "DATA");
1204 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_DATA, "");
1205 static SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1206 "CONTROL");
1207 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_CONTROL, "");
1208