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/10.1/sys/netgraph/ng_socket.c 231823 2012-02-16 14:44:52Z glebius $
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/hash.h>
55 #include <sys/kernel.h>
56 #include <sys/linker.h>
57 #include <sys/lock.h>
58 #include <sys/malloc.h>
59 #include <sys/mbuf.h>
60 #include <sys/mutex.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
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
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
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 /*
242 * Allocate an expendable buffer for the path, chop off
243 * the sockaddr header, and make sure it's NUL terminated.
244 */
245 len = sap->sg_len - 2;
246 path = malloc(len + 1, M_NETGRAPH_PATH, M_WAITOK);
247 bcopy(sap->sg_data, path, len);
248 path[len] = '\0';
249
250 /*
251 * Move the actual message out of mbufs into a linear buffer.
252 * Start by adding up the size of the data. (could use mh_len?)
253 */
254 for (len = 0, m0 = m; m0 != NULL; m0 = m0->m_next)
255 len += m0->m_len;
256
257 /*
258 * Move the data into a linear buffer as well.
259 * Messages are not delivered in mbufs.
260 */
261 msg = malloc(len + 1, M_NETGRAPH_MSG, M_WAITOK);
262 m_copydata(m, 0, len, (char *)msg);
263
264 if (msg->header.version != NG_VERSION) {
265 free(msg, M_NETGRAPH_MSG);
266 error = EINVAL;
267 goto release;
268 }
269
270 /*
271 * Hack alert!
272 * We look into the message and if it mkpeers a node of unknown type, we
273 * try to load it. We need to do this now, in syscall thread, because if
274 * message gets queued and applied later we will get panic.
275 */
276 if (msg->header.typecookie == NGM_GENERIC_COOKIE &&
277 msg->header.cmd == NGM_MKPEER) {
278 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
279
280 if (ng_findtype(mkp->type) == NULL) {
281 char filename[NG_TYPESIZ + 3];
282 int fileid;
283
284 /* Not found, try to load it as a loadable module. */
285 snprintf(filename, sizeof(filename), "ng_%s",
286 mkp->type);
287 error = kern_kldload(curthread, filename, &fileid);
288 if (error != 0) {
289 free(msg, M_NETGRAPH_MSG);
290 goto release;
291 }
292
293 /* See if type has been loaded successfully. */
294 if (ng_findtype(mkp->type) == NULL) {
295 free(msg, M_NETGRAPH_MSG);
296 (void)kern_kldunload(curthread, fileid,
297 LINKER_UNLOAD_NORMAL);
298 error = ENXIO;
299 goto release;
300 }
301 }
302 }
303
304 item = ng_package_msg(msg, M_WAITOK);
305 if ((error = ng_address_path((pcbp->sockdata->node), item, path, 0))
306 != 0) {
307 #ifdef TRACE_MESSAGES
308 printf("ng_address_path: errx=%d\n", error);
309 #endif
310 goto release;
311 }
312
313 #ifdef TRACE_MESSAGES
314 printf("[%x]:<---------[socket]: c=<%d>cmd=%x(%s) f=%x #%d (%s)\n",
315 item->el_dest->nd_ID,
316 msg->header.typecookie,
317 msg->header.cmd,
318 msg->header.cmdstr,
319 msg->header.flags,
320 msg->header.token,
321 item->el_dest->nd_type->name);
322 #endif
323 SAVE_LINE(item);
324 /*
325 * We do not want to return from syscall until the item
326 * is processed by destination node. We register callback
327 * on the item, which will update priv->error when item
328 * was applied.
329 * If ng_snd_item() has queued item, we sleep until
330 * callback wakes us up.
331 */
332 bzero(&apply, sizeof(apply));
333 apply.apply = ng_socket_item_applied;
334 apply.context = priv;
335 item->apply = &apply;
336 priv->error = -1;
337
338 error = ng_snd_item(item, 0);
339
340 mtx_lock(&priv->mtx);
341 if (priv->error == -1)
342 msleep(priv, &priv->mtx, 0, "ngsock", 0);
343 mtx_unlock(&priv->mtx);
344 KASSERT(priv->error != -1,
345 ("ng_socket: priv->error wasn't updated"));
346 error = priv->error;
347
348 release:
349 if (path != NULL)
350 free(path, M_NETGRAPH_PATH);
351 if (control != NULL)
352 m_freem(control);
353 if (m != NULL)
354 m_freem(m);
355 return (error);
356 }
357
358 static int
359 ngc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
360 {
361 struct ngpcb *const pcbp = sotongpcb(so);
362
363 if (pcbp == 0)
364 return (EINVAL);
365 return (ng_bind(nam, pcbp));
366 }
367
368 static int
369 ngc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
370 {
371 /*
372 * At this time refuse to do this.. it used to
373 * do something but it was undocumented and not used.
374 */
375 printf("program tried to connect control socket to remote node\n");
376 return (EINVAL);
377 }
378
379 /***************************************************************
380 Data sockets
381 ***************************************************************/
382
383 static int
384 ngd_attach(struct socket *so, int proto, struct thread *td)
385 {
386 struct ngpcb *const pcbp = sotongpcb(so);
387
388 if (pcbp != NULL)
389 return (EISCONN);
390 return (ng_attach_data(so));
391 }
392
393 static void
394 ngd_detach(struct socket *so)
395 {
396 struct ngpcb *const pcbp = sotongpcb(so);
397
398 KASSERT(pcbp != NULL, ("ngd_detach: pcbp == NULL"));
399 ng_detach_common(pcbp, NG_DATA);
400 }
401
402 static int
403 ngd_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
404 struct mbuf *control, struct thread *td)
405 {
406 struct ngpcb *const pcbp = sotongpcb(so);
407 struct sockaddr_ng *const sap = (struct sockaddr_ng *) addr;
408 int len, error;
409 hook_p hook = NULL;
410 char hookname[NG_HOOKSIZ];
411
412 if ((pcbp == NULL) || (control != NULL)) {
413 error = EINVAL;
414 goto release;
415 }
416 if (pcbp->sockdata == NULL) {
417 error = ENOTCONN;
418 goto release;
419 }
420
421 if (sap == NULL)
422 len = 0; /* Make compiler happy. */
423 else
424 len = sap->sg_len - 2;
425
426 /*
427 * If the user used any of these ways to not specify an address
428 * then handle specially.
429 */
430 if ((sap == NULL) || (len <= 0) || (*sap->sg_data == '\0')) {
431 if (NG_NODE_NUMHOOKS(pcbp->sockdata->node) != 1) {
432 error = EDESTADDRREQ;
433 goto release;
434 }
435 /*
436 * If exactly one hook exists, just use it.
437 * Special case to allow write(2) to work on an ng_socket.
438 */
439 hook = LIST_FIRST(&pcbp->sockdata->node->nd_hooks);
440 } else {
441 if (len >= NG_HOOKSIZ) {
442 error = EINVAL;
443 goto release;
444 }
445
446 /*
447 * chop off the sockaddr header, and make sure it's NUL
448 * terminated
449 */
450 bcopy(sap->sg_data, hookname, len);
451 hookname[len] = '\0';
452
453 /* Find the correct hook from 'hookname' */
454 hook = ng_findhook(pcbp->sockdata->node, hookname);
455 if (hook == NULL) {
456 error = EHOSTUNREACH;
457 goto release;
458 }
459 }
460
461 /* Send data. */
462 NG_SEND_DATA_FLAGS(error, hook, m, NG_WAITOK);
463
464 release:
465 if (control != NULL)
466 m_freem(control);
467 if (m != NULL)
468 m_freem(m);
469 return (error);
470 }
471
472 static int
473 ngd_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
474 {
475 struct ngpcb *const pcbp = sotongpcb(so);
476
477 if (pcbp == 0)
478 return (EINVAL);
479 return (ng_connect_data(nam, pcbp));
480 }
481
482 /*
483 * Used for both data and control sockets
484 */
485 static int
486 ng_getsockaddr(struct socket *so, struct sockaddr **addr)
487 {
488 struct ngpcb *pcbp;
489 struct sockaddr_ng *sg;
490 int sg_len;
491 int error = 0;
492
493 pcbp = sotongpcb(so);
494 if ((pcbp == NULL) || (pcbp->sockdata == NULL))
495 /* XXXGL: can this still happen? */
496 return (EINVAL);
497
498 sg_len = sizeof(struct sockaddr_ng) + NG_NODESIZ -
499 sizeof(sg->sg_data);
500 sg = malloc(sg_len, M_SONAME, M_WAITOK | M_ZERO);
501
502 mtx_lock(&pcbp->sockdata->mtx);
503 if (pcbp->sockdata->node != NULL) {
504 node_p node = pcbp->sockdata->node;
505
506 if (NG_NODE_HAS_NAME(node))
507 bcopy(NG_NODE_NAME(node), sg->sg_data,
508 strlen(NG_NODE_NAME(node)));
509 mtx_unlock(&pcbp->sockdata->mtx);
510
511 sg->sg_len = sg_len;
512 sg->sg_family = AF_NETGRAPH;
513 *addr = (struct sockaddr *)sg;
514 } else {
515 mtx_unlock(&pcbp->sockdata->mtx);
516 free(sg, M_SONAME);
517 error = EINVAL;
518 }
519
520 return (error);
521 }
522
523 /*
524 * Attach a socket to it's protocol specific partner.
525 * For a control socket, actually create a netgraph node and attach
526 * to it as well.
527 */
528
529 static int
530 ng_attach_cntl(struct socket *so)
531 {
532 struct ngsock *priv;
533 struct ngpcb *pcbp;
534 node_p node;
535 int error;
536
537 /* Setup protocol control block */
538 if ((error = ng_attach_common(so, NG_CONTROL)) != 0)
539 return (error);
540 pcbp = sotongpcb(so);
541
542 /* Make the generic node components */
543 if ((error = ng_make_node_common(&typestruct, &node)) != 0) {
544 ng_detach_common(pcbp, NG_CONTROL);
545 return (error);
546 }
547
548 /*
549 * Allocate node private info and hash. We start
550 * with 16 hash entries, however we may grow later
551 * in ngs_newhook(). We can't predict how much hooks
552 * does this node plan to have.
553 */
554 priv = malloc(sizeof(*priv), M_NETGRAPH_SOCK, M_WAITOK | M_ZERO);
555 priv->hash = hashinit(16, M_NETGRAPH_SOCK, &priv->hmask);
556
557 /* Initialize mutex. */
558 mtx_init(&priv->mtx, "ng_socket", NULL, MTX_DEF);
559
560 /* Link the pcb the private data. */
561 priv->ctlsock = pcbp;
562 pcbp->sockdata = priv;
563 priv->refs++;
564 priv->node = node;
565 pcbp->node_id = node->nd_ID; /* hint for netstat(1) */
566
567 /* Link the node and the private data. */
568 NG_NODE_SET_PRIVATE(priv->node, priv);
569 NG_NODE_REF(priv->node);
570 priv->refs++;
571
572 return (0);
573 }
574
575 static int
576 ng_attach_data(struct socket *so)
577 {
578 return (ng_attach_common(so, NG_DATA));
579 }
580
581 /*
582 * Set up a socket protocol control block.
583 * This code is shared between control and data sockets.
584 */
585 static int
586 ng_attach_common(struct socket *so, int type)
587 {
588 struct ngpcb *pcbp;
589 int error;
590
591 /* Standard socket setup stuff. */
592 error = soreserve(so, ngpdg_sendspace, ngpdg_recvspace);
593 if (error)
594 return (error);
595
596 /* Allocate the pcb. */
597 pcbp = malloc(sizeof(struct ngpcb), M_PCB, M_WAITOK | M_ZERO);
598 pcbp->type = type;
599
600 /* Link the pcb and the socket. */
601 so->so_pcb = (caddr_t)pcbp;
602 pcbp->ng_socket = so;
603
604 /* Add the socket to linked list */
605 mtx_lock(&ngsocketlist_mtx);
606 LIST_INSERT_HEAD(&ngsocklist, pcbp, socks);
607 mtx_unlock(&ngsocketlist_mtx);
608 return (0);
609 }
610
611 /*
612 * Disassociate the socket from it's protocol specific
613 * partner. If it's attached to a node's private data structure,
614 * then unlink from that too. If we were the last socket attached to it,
615 * then shut down the entire node. Shared code for control and data sockets.
616 */
617 static void
618 ng_detach_common(struct ngpcb *pcbp, int which)
619 {
620 struct ngsock *priv = pcbp->sockdata;
621
622 if (priv != NULL) {
623 mtx_lock(&priv->mtx);
624
625 switch (which) {
626 case NG_CONTROL:
627 priv->ctlsock = NULL;
628 break;
629 case NG_DATA:
630 priv->datasock = NULL;
631 break;
632 default:
633 panic("%s", __func__);
634 }
635 pcbp->sockdata = NULL;
636 pcbp->node_id = 0;
637
638 ng_socket_free_priv(priv);
639 }
640
641 pcbp->ng_socket->so_pcb = NULL;
642 mtx_lock(&ngsocketlist_mtx);
643 LIST_REMOVE(pcbp, socks);
644 mtx_unlock(&ngsocketlist_mtx);
645 free(pcbp, M_PCB);
646 }
647
648 /*
649 * Remove a reference from node private data.
650 */
651 static void
652 ng_socket_free_priv(struct ngsock *priv)
653 {
654 mtx_assert(&priv->mtx, MA_OWNED);
655
656 priv->refs--;
657
658 if (priv->refs == 0) {
659 mtx_destroy(&priv->mtx);
660 hashdestroy(priv->hash, M_NETGRAPH_SOCK, priv->hmask);
661 free(priv, M_NETGRAPH_SOCK);
662 return;
663 }
664
665 if ((priv->refs == 1) && (priv->node != NULL)) {
666 node_p node = priv->node;
667
668 priv->node = NULL;
669 mtx_unlock(&priv->mtx);
670 NG_NODE_UNREF(node);
671 ng_rmnode_self(node);
672 } else
673 mtx_unlock(&priv->mtx);
674 }
675
676 /*
677 * Connect the data socket to a named control socket node.
678 */
679 static int
680 ng_connect_data(struct sockaddr *nam, struct ngpcb *pcbp)
681 {
682 struct sockaddr_ng *sap;
683 node_p farnode;
684 struct ngsock *priv;
685 int error;
686 item_p item;
687
688 /* If we are already connected, don't do it again. */
689 if (pcbp->sockdata != NULL)
690 return (EISCONN);
691
692 /*
693 * Find the target (victim) and check it doesn't already have
694 * a data socket. Also check it is a 'socket' type node.
695 * Use ng_package_data() and ng_address_path() to do this.
696 */
697
698 sap = (struct sockaddr_ng *) nam;
699 /* The item will hold the node reference. */
700 item = ng_package_data(NULL, NG_WAITOK);
701
702 if ((error = ng_address_path(NULL, item, sap->sg_data, 0)))
703 return (error); /* item is freed on failure */
704
705 /*
706 * Extract node from item and free item. Remember we now have
707 * a reference on the node. The item holds it for us.
708 * when we free the item we release the reference.
709 */
710 farnode = item->el_dest; /* shortcut */
711 if (strcmp(farnode->nd_type->name, NG_SOCKET_NODE_TYPE) != 0) {
712 NG_FREE_ITEM(item); /* drop the reference to the node */
713 return (EINVAL);
714 }
715 priv = NG_NODE_PRIVATE(farnode);
716 if (priv->datasock != NULL) {
717 NG_FREE_ITEM(item); /* drop the reference to the node */
718 return (EADDRINUSE);
719 }
720
721 /*
722 * Link the PCB and the private data struct. and note the extra
723 * reference. Drop the extra reference on the node.
724 */
725 mtx_lock(&priv->mtx);
726 priv->datasock = pcbp;
727 pcbp->sockdata = priv;
728 pcbp->node_id = priv->node->nd_ID; /* hint for netstat(1) */
729 priv->refs++;
730 mtx_unlock(&priv->mtx);
731 NG_FREE_ITEM(item); /* drop the reference to the node */
732 return (0);
733 }
734
735 /*
736 * Binding a socket means giving the corresponding node a name
737 */
738 static int
739 ng_bind(struct sockaddr *nam, struct ngpcb *pcbp)
740 {
741 struct ngsock *const priv = pcbp->sockdata;
742 struct sockaddr_ng *const sap = (struct sockaddr_ng *) nam;
743
744 if (priv == NULL) {
745 TRAP_ERROR;
746 return (EINVAL);
747 }
748 if ((sap->sg_len < 4) || (sap->sg_len > (NG_NODESIZ + 2)) ||
749 (sap->sg_data[0] == '\0') ||
750 (sap->sg_data[sap->sg_len - 3] != '\0')) {
751 TRAP_ERROR;
752 return (EINVAL);
753 }
754 return (ng_name_node(priv->node, sap->sg_data));
755 }
756
757 /***************************************************************
758 Netgraph node
759 ***************************************************************/
760
761 /*
762 * You can only create new nodes from the socket end of things.
763 */
764 static int
765 ngs_constructor(node_p nodep)
766 {
767 return (EINVAL);
768 }
769
770 static void
771 ngs_rehash(node_p node)
772 {
773 struct ngsock *priv = NG_NODE_PRIVATE(node);
774 struct ngshash *new;
775 struct hookpriv *hp;
776 hook_p hook;
777 uint32_t h;
778 u_long hmask;
779
780 new = hashinit_flags((priv->hmask + 1) * 2, M_NETGRAPH_SOCK, &hmask,
781 HASH_NOWAIT);
782 if (new == NULL)
783 return;
784
785 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
786 hp = NG_HOOK_PRIVATE(hook);
787 #ifdef INVARIANTS
788 LIST_REMOVE(hp, next);
789 #endif
790 h = hash32_str(NG_HOOK_NAME(hook), HASHINIT) & hmask;
791 LIST_INSERT_HEAD(&new[h], hp, next);
792 }
793
794 hashdestroy(priv->hash, M_NETGRAPH_SOCK, priv->hmask);
795 priv->hash = new;
796 priv->hmask = hmask;
797 }
798
799 /*
800 * We allow any hook to be connected to the node.
801 * There is no per-hook private information though.
802 */
803 static int
804 ngs_newhook(node_p node, hook_p hook, const char *name)
805 {
806 struct ngsock *const priv = NG_NODE_PRIVATE(node);
807 struct hookpriv *hp;
808 uint32_t h;
809
810 hp = malloc(sizeof(*hp), M_NETGRAPH_SOCK, M_NOWAIT);
811 if (hp == NULL)
812 return (ENOMEM);
813 if (node->nd_numhooks * 2 > priv->hmask)
814 ngs_rehash(node);
815 hp->hook = hook;
816 h = hash32_str(name, HASHINIT) & priv->hmask;
817 LIST_INSERT_HEAD(&priv->hash[h], hp, next);
818 NG_HOOK_SET_PRIVATE(hook, hp);
819
820 return (0);
821 }
822
823 /*
824 * If only one hook, allow read(2) and write(2) to work.
825 */
826 static int
827 ngs_connect(hook_p hook)
828 {
829 node_p node = NG_HOOK_NODE(hook);
830 struct ngsock *priv = NG_NODE_PRIVATE(node);
831
832 if ((priv->datasock) && (priv->datasock->ng_socket)) {
833 if (NG_NODE_NUMHOOKS(node) == 1)
834 priv->datasock->ng_socket->so_state |= SS_ISCONNECTED;
835 else
836 priv->datasock->ng_socket->so_state &= ~SS_ISCONNECTED;
837 }
838 return (0);
839 }
840
841 /* Look up hook by name */
842 static hook_p
843 ngs_findhook(node_p node, const char *name)
844 {
845 struct ngsock *priv = NG_NODE_PRIVATE(node);
846 struct hookpriv *hp;
847 uint32_t h;
848
849 /*
850 * Microoptimisation for an ng_socket with
851 * a single hook, which is a common case.
852 */
853 if (node->nd_numhooks == 1) {
854 hook_p hook;
855
856 hook = LIST_FIRST(&node->nd_hooks);
857
858 if (strcmp(NG_HOOK_NAME(hook), name) == 0)
859 return (hook);
860 else
861 return (NULL);
862 }
863
864 h = hash32_str(name, HASHINIT) & priv->hmask;
865
866 LIST_FOREACH(hp, &priv->hash[h], next)
867 if (strcmp(NG_HOOK_NAME(hp->hook), name) == 0)
868 return (hp->hook);
869
870 return (NULL);
871 }
872
873 /*
874 * Incoming messages get passed up to the control socket.
875 * Unless they are for us specifically (socket_type)
876 */
877 static int
878 ngs_rcvmsg(node_p node, item_p item, hook_p lasthook)
879 {
880 struct ngsock *const priv = NG_NODE_PRIVATE(node);
881 struct ngpcb *pcbp;
882 struct socket *so;
883 struct sockaddr_ng addr;
884 struct ng_mesg *msg;
885 struct mbuf *m;
886 ng_ID_t retaddr = NGI_RETADDR(item);
887 int addrlen;
888 int error = 0;
889
890 NGI_GET_MSG(item, msg);
891 NG_FREE_ITEM(item);
892
893 /*
894 * Grab priv->mtx here to prevent destroying of control socket
895 * after checking that priv->ctlsock is not NULL.
896 */
897 mtx_lock(&priv->mtx);
898 pcbp = priv->ctlsock;
899
900 /*
901 * Only allow mesgs to be passed if we have the control socket.
902 * Data sockets can only support the generic messages.
903 */
904 if (pcbp == NULL) {
905 mtx_unlock(&priv->mtx);
906 TRAP_ERROR;
907 NG_FREE_MSG(msg);
908 return (EINVAL);
909 }
910 so = pcbp->ng_socket;
911 SOCKBUF_LOCK(&so->so_rcv);
912
913 /* As long as the race is handled, priv->mtx may be unlocked now. */
914 mtx_unlock(&priv->mtx);
915
916 #ifdef TRACE_MESSAGES
917 printf("[%x]:---------->[socket]: c=<%d>cmd=%x(%s) f=%x #%d\n",
918 retaddr,
919 msg->header.typecookie,
920 msg->header.cmd,
921 msg->header.cmdstr,
922 msg->header.flags,
923 msg->header.token);
924 #endif
925
926 if (msg->header.typecookie == NGM_SOCKET_COOKIE) {
927 switch (msg->header.cmd) {
928 case NGM_SOCK_CMD_NOLINGER:
929 priv->flags |= NGS_FLAG_NOLINGER;
930 break;
931 case NGM_SOCK_CMD_LINGER:
932 priv->flags &= ~NGS_FLAG_NOLINGER;
933 break;
934 default:
935 error = EINVAL; /* unknown command */
936 }
937 SOCKBUF_UNLOCK(&so->so_rcv);
938
939 /* Free the message and return. */
940 NG_FREE_MSG(msg);
941 return (error);
942 }
943
944 /* Get the return address into a sockaddr. */
945 bzero(&addr, sizeof(addr));
946 addr.sg_len = sizeof(addr);
947 addr.sg_family = AF_NETGRAPH;
948 addrlen = snprintf((char *)&addr.sg_data, sizeof(addr.sg_data),
949 "[%x]:", retaddr);
950 if (addrlen < 0 || addrlen > sizeof(addr.sg_data)) {
951 SOCKBUF_UNLOCK(&so->so_rcv);
952 printf("%s: snprintf([%x]) failed - %d\n", __func__, retaddr,
953 addrlen);
954 NG_FREE_MSG(msg);
955 return (EINVAL);
956 }
957
958 /* Copy the message itself into an mbuf chain. */
959 m = m_devget((caddr_t)msg, sizeof(struct ng_mesg) + msg->header.arglen,
960 0, NULL, NULL);
961
962 /*
963 * Here we free the message. We need to do that
964 * regardless of whether we got mbufs.
965 */
966 NG_FREE_MSG(msg);
967
968 if (m == NULL) {
969 SOCKBUF_UNLOCK(&so->so_rcv);
970 TRAP_ERROR;
971 return (ENOBUFS);
972 }
973
974 /* Send it up to the socket. */
975 if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)&addr, m,
976 NULL) == 0) {
977 SOCKBUF_UNLOCK(&so->so_rcv);
978 TRAP_ERROR;
979 m_freem(m);
980 return (ENOBUFS);
981 }
982 sorwakeup_locked(so);
983
984 return (error);
985 }
986
987 /*
988 * Receive data on a hook
989 */
990 static int
991 ngs_rcvdata(hook_p hook, item_p item)
992 {
993 struct ngsock *const priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
994 struct ngpcb *const pcbp = priv->datasock;
995 struct socket *so;
996 struct sockaddr_ng *addr;
997 char *addrbuf[NG_HOOKSIZ + 4];
998 int addrlen;
999 struct mbuf *m;
1000
1001 NGI_GET_M(item, m);
1002 NG_FREE_ITEM(item);
1003
1004 /* If there is no data socket, black-hole it. */
1005 if (pcbp == NULL) {
1006 NG_FREE_M(m);
1007 return (0);
1008 }
1009 so = pcbp->ng_socket;
1010
1011 /* Get the return address into a sockaddr. */
1012 addrlen = strlen(NG_HOOK_NAME(hook)); /* <= NG_HOOKSIZ - 1 */
1013 addr = (struct sockaddr_ng *) addrbuf;
1014 addr->sg_len = addrlen + 3;
1015 addr->sg_family = AF_NETGRAPH;
1016 bcopy(NG_HOOK_NAME(hook), addr->sg_data, addrlen);
1017 addr->sg_data[addrlen] = '\0';
1018
1019 /* Try to tell the socket which hook it came in on. */
1020 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)addr, m, NULL) == 0) {
1021 m_freem(m);
1022 TRAP_ERROR;
1023 return (ENOBUFS);
1024 }
1025 sorwakeup(so);
1026 return (0);
1027 }
1028
1029 /*
1030 * Hook disconnection
1031 *
1032 * For this type, removal of the last link destroys the node
1033 * if the NOLINGER flag is set.
1034 */
1035 static int
1036 ngs_disconnect(hook_p hook)
1037 {
1038 node_p node = NG_HOOK_NODE(hook);
1039 struct ngsock *const priv = NG_NODE_PRIVATE(node);
1040 struct hookpriv *hp = NG_HOOK_PRIVATE(hook);
1041
1042 LIST_REMOVE(hp, next);
1043 free(hp, M_NETGRAPH_SOCK);
1044
1045 if ((priv->datasock) && (priv->datasock->ng_socket)) {
1046 if (NG_NODE_NUMHOOKS(node) == 1)
1047 priv->datasock->ng_socket->so_state |= SS_ISCONNECTED;
1048 else
1049 priv->datasock->ng_socket->so_state &= ~SS_ISCONNECTED;
1050 }
1051
1052 if ((priv->flags & NGS_FLAG_NOLINGER) &&
1053 (NG_NODE_NUMHOOKS(node) == 0) && (NG_NODE_IS_VALID(node)))
1054 ng_rmnode_self(node);
1055
1056 return (0);
1057 }
1058
1059 /*
1060 * Do local shutdown processing.
1061 * In this case, that involves making sure the socket
1062 * knows we should be shutting down.
1063 */
1064 static int
1065 ngs_shutdown(node_p node)
1066 {
1067 struct ngsock *const priv = NG_NODE_PRIVATE(node);
1068 struct ngpcb *dpcbp, *pcbp;
1069
1070 mtx_lock(&priv->mtx);
1071 dpcbp = priv->datasock;
1072 pcbp = priv->ctlsock;
1073
1074 if (dpcbp != NULL)
1075 soisdisconnected(dpcbp->ng_socket);
1076
1077 if (pcbp != NULL)
1078 soisdisconnected(pcbp->ng_socket);
1079
1080 priv->node = NULL;
1081 NG_NODE_SET_PRIVATE(node, NULL);
1082 ng_socket_free_priv(priv);
1083
1084 NG_NODE_UNREF(node);
1085 return (0);
1086 }
1087
1088 static void
1089 ng_socket_item_applied(void *context, int error)
1090 {
1091 struct ngsock *const priv = (struct ngsock *)context;
1092
1093 mtx_lock(&priv->mtx);
1094 priv->error = error;
1095 wakeup(priv);
1096 mtx_unlock(&priv->mtx);
1097
1098 }
1099
1100 static int
1101 dummy_disconnect(struct socket *so)
1102 {
1103 return (0);
1104 }
1105 /*
1106 * Control and data socket type descriptors
1107 *
1108 * XXXRW: Perhaps _close should do something?
1109 */
1110
1111 static struct pr_usrreqs ngc_usrreqs = {
1112 .pru_abort = NULL,
1113 .pru_attach = ngc_attach,
1114 .pru_bind = ngc_bind,
1115 .pru_connect = ngc_connect,
1116 .pru_detach = ngc_detach,
1117 .pru_disconnect = dummy_disconnect,
1118 .pru_peeraddr = NULL,
1119 .pru_send = ngc_send,
1120 .pru_shutdown = NULL,
1121 .pru_sockaddr = ng_getsockaddr,
1122 .pru_close = NULL,
1123 };
1124
1125 static struct pr_usrreqs ngd_usrreqs = {
1126 .pru_abort = NULL,
1127 .pru_attach = ngd_attach,
1128 .pru_bind = NULL,
1129 .pru_connect = ngd_connect,
1130 .pru_detach = ngd_detach,
1131 .pru_disconnect = dummy_disconnect,
1132 .pru_peeraddr = NULL,
1133 .pru_send = ngd_send,
1134 .pru_shutdown = NULL,
1135 .pru_sockaddr = ng_getsockaddr,
1136 .pru_close = NULL,
1137 };
1138
1139 /*
1140 * Definitions of protocols supported in the NETGRAPH domain.
1141 */
1142
1143 extern struct domain ngdomain; /* stop compiler warnings */
1144
1145 static struct protosw ngsw[] = {
1146 {
1147 .pr_type = SOCK_DGRAM,
1148 .pr_domain = &ngdomain,
1149 .pr_protocol = NG_CONTROL,
1150 .pr_flags = PR_ATOMIC | PR_ADDR /* | PR_RIGHTS */,
1151 .pr_usrreqs = &ngc_usrreqs
1152 },
1153 {
1154 .pr_type = SOCK_DGRAM,
1155 .pr_domain = &ngdomain,
1156 .pr_protocol = NG_DATA,
1157 .pr_flags = PR_ATOMIC | PR_ADDR,
1158 .pr_usrreqs = &ngd_usrreqs
1159 }
1160 };
1161
1162 struct domain ngdomain = {
1163 .dom_family = AF_NETGRAPH,
1164 .dom_name = "netgraph",
1165 .dom_protosw = ngsw,
1166 .dom_protoswNPROTOSW = &ngsw[sizeof(ngsw) / sizeof(ngsw[0])]
1167 };
1168
1169 /*
1170 * Handle loading and unloading for this node type.
1171 * This is to handle auxiliary linkages (e.g protocol domain addition).
1172 */
1173 static int
1174 ngs_mod_event(module_t mod, int event, void *data)
1175 {
1176 int error = 0;
1177
1178 switch (event) {
1179 case MOD_LOAD:
1180 mtx_init(&ngsocketlist_mtx, "ng_socketlist", NULL, MTX_DEF);
1181 break;
1182 case MOD_UNLOAD:
1183 /* Ensure there are no open netgraph sockets. */
1184 if (!LIST_EMPTY(&ngsocklist)) {
1185 error = EBUSY;
1186 break;
1187 }
1188 #ifdef NOTYET
1189 /* Unregister protocol domain XXX can't do this yet.. */
1190 #endif
1191 error = EBUSY;
1192 break;
1193 default:
1194 error = EOPNOTSUPP;
1195 break;
1196 }
1197 return (error);
1198 }
1199
1200 VNET_DOMAIN_SET(ng);
1201
1202 SYSCTL_INT(_net_graph, OID_AUTO, family, CTLFLAG_RD, 0, AF_NETGRAPH, "");
1203 static SYSCTL_NODE(_net_graph, OID_AUTO, data, CTLFLAG_RW, 0, "DATA");
1204 SYSCTL_INT(_net_graph_data, OID_AUTO, proto, CTLFLAG_RD, 0, NG_DATA, "");
1205 static SYSCTL_NODE(_net_graph, OID_AUTO, control, CTLFLAG_RW, 0, "CONTROL");
1206 SYSCTL_INT(_net_graph_control, OID_AUTO, proto, CTLFLAG_RD, 0, NG_CONTROL, "");
1207
Cache object: 08618a153ea213a508a6542b9d1a1c91
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