xref: /freebsd/sys/netgraph/netflow/ng_netflow.c (revision 5d3e7166f6a0187fa3f8831b16a06bd9955c21ff)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010-2011 Alexander V. Chernikov <melifaro@ipfw.ru>
5  * Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org>
6  * Copyright (c) 2001-2003 Roman V. Palagin <romanp@unshadow.net>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $SourceForge: ng_netflow.c,v 1.30 2004/09/05 11:37:43 glebius Exp $
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include "opt_inet.h"
37 #include "opt_inet6.h"
38 #include "opt_route.h"
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/counter.h>
43 #include <sys/kernel.h>
44 #include <sys/ktr.h>
45 #include <sys/limits.h>
46 #include <sys/malloc.h>
47 #include <sys/mbuf.h>
48 #include <sys/socket.h>
49 #include <sys/syslog.h>
50 #include <sys/ctype.h>
51 #include <vm/uma.h>
52 
53 #include <net/if.h>
54 #include <net/ethernet.h>
55 #include <net/route.h>
56 #include <net/if_arp.h>
57 #include <net/if_var.h>
58 #include <net/if_private.h>
59 #include <net/if_vlan_var.h>
60 #include <net/bpf.h>
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #include <netinet/ip6.h>
65 #include <netinet/tcp.h>
66 #include <netinet/udp.h>
67 #include <netinet/sctp.h>
68 
69 #include <netgraph/ng_message.h>
70 #include <netgraph/ng_parse.h>
71 #include <netgraph/netgraph.h>
72 #include <netgraph/netflow/netflow.h>
73 #include <netgraph/netflow/netflow_v9.h>
74 #include <netgraph/netflow/ng_netflow.h>
75 
76 /* Netgraph methods */
77 static ng_constructor_t	ng_netflow_constructor;
78 static ng_rcvmsg_t	ng_netflow_rcvmsg;
79 static ng_close_t	ng_netflow_close;
80 static ng_shutdown_t	ng_netflow_rmnode;
81 static ng_newhook_t	ng_netflow_newhook;
82 static ng_rcvdata_t	ng_netflow_rcvdata;
83 static ng_disconnect_t	ng_netflow_disconnect;
84 
85 /* Parse type for struct ng_netflow_info */
86 static const struct ng_parse_struct_field ng_netflow_info_type_fields[]
87 	= NG_NETFLOW_INFO_TYPE;
88 static const struct ng_parse_type ng_netflow_info_type = {
89 	&ng_parse_struct_type,
90 	&ng_netflow_info_type_fields
91 };
92 
93 /*  Parse type for struct ng_netflow_ifinfo */
94 static const struct ng_parse_struct_field ng_netflow_ifinfo_type_fields[]
95 	= NG_NETFLOW_IFINFO_TYPE;
96 static const struct ng_parse_type ng_netflow_ifinfo_type = {
97 	&ng_parse_struct_type,
98 	&ng_netflow_ifinfo_type_fields
99 };
100 
101 /* Parse type for struct ng_netflow_setdlt */
102 static const struct ng_parse_struct_field ng_netflow_setdlt_type_fields[]
103 	= NG_NETFLOW_SETDLT_TYPE;
104 static const struct ng_parse_type ng_netflow_setdlt_type = {
105 	&ng_parse_struct_type,
106 	&ng_netflow_setdlt_type_fields
107 };
108 
109 /* Parse type for ng_netflow_setifindex */
110 static const struct ng_parse_struct_field ng_netflow_setifindex_type_fields[]
111 	= NG_NETFLOW_SETIFINDEX_TYPE;
112 static const struct ng_parse_type ng_netflow_setifindex_type = {
113 	&ng_parse_struct_type,
114 	&ng_netflow_setifindex_type_fields
115 };
116 
117 /* Parse type for ng_netflow_settimeouts */
118 static const struct ng_parse_struct_field ng_netflow_settimeouts_type_fields[]
119 	= NG_NETFLOW_SETTIMEOUTS_TYPE;
120 static const struct ng_parse_type ng_netflow_settimeouts_type = {
121 	&ng_parse_struct_type,
122 	&ng_netflow_settimeouts_type_fields
123 };
124 
125 /* Parse type for ng_netflow_setconfig */
126 static const struct ng_parse_struct_field ng_netflow_setconfig_type_fields[]
127 	= NG_NETFLOW_SETCONFIG_TYPE;
128 static const struct ng_parse_type ng_netflow_setconfig_type = {
129 	&ng_parse_struct_type,
130 	&ng_netflow_setconfig_type_fields
131 };
132 
133 /* Parse type for ng_netflow_settemplate */
134 static const struct ng_parse_struct_field ng_netflow_settemplate_type_fields[]
135 	= NG_NETFLOW_SETTEMPLATE_TYPE;
136 static const struct ng_parse_type ng_netflow_settemplate_type = {
137 	&ng_parse_struct_type,
138 	&ng_netflow_settemplate_type_fields
139 };
140 
141 /* Parse type for ng_netflow_setmtu */
142 static const struct ng_parse_struct_field ng_netflow_setmtu_type_fields[]
143 	= NG_NETFLOW_SETMTU_TYPE;
144 static const struct ng_parse_type ng_netflow_setmtu_type = {
145 	&ng_parse_struct_type,
146 	&ng_netflow_setmtu_type_fields
147 };
148 
149 /* Parse type for struct ng_netflow_v9info */
150 static const struct ng_parse_struct_field ng_netflow_v9info_type_fields[]
151 	= NG_NETFLOW_V9INFO_TYPE;
152 static const struct ng_parse_type ng_netflow_v9info_type = {
153 	&ng_parse_struct_type,
154 	&ng_netflow_v9info_type_fields
155 };
156 
157 /* List of commands and how to convert arguments to/from ASCII */
158 static const struct ng_cmdlist ng_netflow_cmds[] = {
159        {
160 	 NGM_NETFLOW_COOKIE,
161 	 NGM_NETFLOW_INFO,
162 	 "info",
163 	 NULL,
164 	 &ng_netflow_info_type
165        },
166        {
167 	NGM_NETFLOW_COOKIE,
168 	NGM_NETFLOW_IFINFO,
169 	"ifinfo",
170 	&ng_parse_uint16_type,
171 	&ng_netflow_ifinfo_type
172        },
173        {
174 	NGM_NETFLOW_COOKIE,
175 	NGM_NETFLOW_SETDLT,
176 	"setdlt",
177 	&ng_netflow_setdlt_type,
178 	NULL
179        },
180        {
181 	NGM_NETFLOW_COOKIE,
182 	NGM_NETFLOW_SETIFINDEX,
183 	"setifindex",
184 	&ng_netflow_setifindex_type,
185 	NULL
186        },
187        {
188 	NGM_NETFLOW_COOKIE,
189 	NGM_NETFLOW_SETTIMEOUTS,
190 	"settimeouts",
191 	&ng_netflow_settimeouts_type,
192 	NULL
193        },
194        {
195 	NGM_NETFLOW_COOKIE,
196 	NGM_NETFLOW_SETCONFIG,
197 	"setconfig",
198 	&ng_netflow_setconfig_type,
199 	NULL
200        },
201        {
202 	NGM_NETFLOW_COOKIE,
203 	NGM_NETFLOW_SETTEMPLATE,
204 	"settemplate",
205 	&ng_netflow_settemplate_type,
206 	NULL
207        },
208        {
209 	NGM_NETFLOW_COOKIE,
210 	NGM_NETFLOW_SETMTU,
211 	"setmtu",
212 	&ng_netflow_setmtu_type,
213 	NULL
214        },
215        {
216 	 NGM_NETFLOW_COOKIE,
217 	 NGM_NETFLOW_V9INFO,
218 	 "v9info",
219 	 NULL,
220 	 &ng_netflow_v9info_type
221        },
222        { 0 }
223 };
224 
225 /* Netgraph node type descriptor */
226 static struct ng_type ng_netflow_typestruct = {
227 	.version =	NG_ABI_VERSION,
228 	.name =		NG_NETFLOW_NODE_TYPE,
229 	.constructor =	ng_netflow_constructor,
230 	.rcvmsg =	ng_netflow_rcvmsg,
231 	.close =	ng_netflow_close,
232 	.shutdown =	ng_netflow_rmnode,
233 	.newhook =	ng_netflow_newhook,
234 	.rcvdata =	ng_netflow_rcvdata,
235 	.disconnect =	ng_netflow_disconnect,
236 	.cmdlist =	ng_netflow_cmds,
237 };
238 NETGRAPH_INIT(netflow, &ng_netflow_typestruct);
239 
240 /* Called at node creation */
241 static int
242 ng_netflow_constructor(node_p node)
243 {
244 	priv_p priv;
245 	int i;
246 
247 	/* Initialize private data */
248 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO);
249 
250 	/* Initialize fib data */
251 	priv->maxfibs = rt_numfibs;
252 	priv->fib_data = malloc(sizeof(fib_export_p) * priv->maxfibs,
253 	    M_NETGRAPH, M_WAITOK | M_ZERO);
254 
255 	/* Make node and its data point at each other */
256 	NG_NODE_SET_PRIVATE(node, priv);
257 	priv->node = node;
258 
259 	/* Initialize timeouts to default values */
260 	priv->nfinfo_inact_t = INACTIVE_TIMEOUT;
261 	priv->nfinfo_act_t = ACTIVE_TIMEOUT;
262 
263 	/* Set default config */
264 	for (i = 0; i < NG_NETFLOW_MAXIFACES; i++)
265 		priv->ifaces[i].info.conf = NG_NETFLOW_CONF_INGRESS;
266 
267 	/* Initialize callout handle */
268 	callout_init(&priv->exp_callout, 1);
269 
270 	/* Allocate memory and set up flow cache */
271 	ng_netflow_cache_init(priv);
272 
273 	return (0);
274 }
275 
276 /*
277  * ng_netflow supports two hooks: data and export.
278  * Incoming traffic is expected on data, and expired
279  * netflow datagrams are sent to export.
280  */
281 static int
282 ng_netflow_newhook(node_p node, hook_p hook, const char *name)
283 {
284 	const priv_p priv = NG_NODE_PRIVATE(node);
285 
286 	if (strncmp(name, NG_NETFLOW_HOOK_DATA,	/* an iface hook? */
287 	    strlen(NG_NETFLOW_HOOK_DATA)) == 0) {
288 		iface_p iface;
289 		int ifnum = -1;
290 		const char *cp;
291 		char *eptr;
292 
293 		cp = name + strlen(NG_NETFLOW_HOOK_DATA);
294 		if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
295 			return (EINVAL);
296 
297 		ifnum = (int)strtoul(cp, &eptr, 10);
298 		if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
299 			return (EINVAL);
300 
301 		/* See if hook is already connected */
302 		if (priv->ifaces[ifnum].hook != NULL)
303 			return (EISCONN);
304 
305 		iface = &priv->ifaces[ifnum];
306 
307 		/* Link private info and hook together */
308 		NG_HOOK_SET_PRIVATE(hook, iface);
309 		iface->hook = hook;
310 
311 		/*
312 		 * In most cases traffic accounting is done on an
313 		 * Ethernet interface, so default data link type
314 		 * will be DLT_EN10MB.
315 		 */
316 		iface->info.ifinfo_dlt = DLT_EN10MB;
317 
318 	} else if (strncmp(name, NG_NETFLOW_HOOK_OUT,
319 	    strlen(NG_NETFLOW_HOOK_OUT)) == 0) {
320 		iface_p iface;
321 		int ifnum = -1;
322 		const char *cp;
323 		char *eptr;
324 
325 		cp = name + strlen(NG_NETFLOW_HOOK_OUT);
326 		if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
327 			return (EINVAL);
328 
329 		ifnum = (int)strtoul(cp, &eptr, 10);
330 		if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
331 			return (EINVAL);
332 
333 		/* See if hook is already connected */
334 		if (priv->ifaces[ifnum].out != NULL)
335 			return (EISCONN);
336 
337 		iface = &priv->ifaces[ifnum];
338 
339 		/* Link private info and hook together */
340 		NG_HOOK_SET_PRIVATE(hook, iface);
341 		iface->out = hook;
342 
343 	} else if (strcmp(name, NG_NETFLOW_HOOK_EXPORT) == 0) {
344 		if (priv->export != NULL)
345 			return (EISCONN);
346 
347 		/* Netflow version 5 supports 32-bit counters only */
348 		if (CNTR_MAX == UINT64_MAX)
349 			return (EINVAL);
350 
351 		priv->export = hook;
352 
353 		/* Exporter is ready. Let's schedule expiry. */
354 		callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire,
355 		    (void *)priv);
356 	} else if (strcmp(name, NG_NETFLOW_HOOK_EXPORT9) == 0) {
357 		if (priv->export9 != NULL)
358 			return (EISCONN);
359 
360 		priv->export9 = hook;
361 
362 		/* Exporter is ready. Let's schedule expiry. */
363 		callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire,
364 		    (void *)priv);
365 	} else
366 		return (EINVAL);
367 
368 	return (0);
369 }
370 
371 /* Get a netgraph control message. */
372 static int
373 ng_netflow_rcvmsg (node_p node, item_p item, hook_p lasthook)
374 {
375 	const priv_p priv = NG_NODE_PRIVATE(node);
376 	struct ng_mesg *resp = NULL;
377 	int error = 0;
378 	struct ng_mesg *msg;
379 
380 	NGI_GET_MSG(item, msg);
381 
382 	/* Deal with message according to cookie and command */
383 	switch (msg->header.typecookie) {
384 	case NGM_NETFLOW_COOKIE:
385 		switch (msg->header.cmd) {
386 		case NGM_NETFLOW_INFO:
387 		    {
388 			struct ng_netflow_info *i;
389 
390 			NG_MKRESPONSE(resp, msg, sizeof(struct ng_netflow_info),
391 			    M_NOWAIT);
392 			i = (struct ng_netflow_info *)resp->data;
393 			ng_netflow_copyinfo(priv, i);
394 
395 			break;
396 		    }
397 		case NGM_NETFLOW_IFINFO:
398 		    {
399 			struct ng_netflow_ifinfo *i;
400 			const uint16_t *index;
401 
402 			if (msg->header.arglen != sizeof(uint16_t))
403 				 ERROUT(EINVAL);
404 
405 			index  = (uint16_t *)msg->data;
406 			if (*index >= NG_NETFLOW_MAXIFACES)
407 				ERROUT(EINVAL);
408 
409 			/* connected iface? */
410 			if (priv->ifaces[*index].hook == NULL)
411 				 ERROUT(EINVAL);
412 
413 			NG_MKRESPONSE(resp, msg,
414 			     sizeof(struct ng_netflow_ifinfo), M_NOWAIT);
415 			i = (struct ng_netflow_ifinfo *)resp->data;
416 			memcpy((void *)i, (void *)&priv->ifaces[*index].info,
417 			    sizeof(priv->ifaces[*index].info));
418 
419 			break;
420 		    }
421 		case NGM_NETFLOW_SETDLT:
422 		    {
423 			struct ng_netflow_setdlt *set;
424 			struct ng_netflow_iface *iface;
425 
426 			if (msg->header.arglen !=
427 			    sizeof(struct ng_netflow_setdlt))
428 				ERROUT(EINVAL);
429 
430 			set = (struct ng_netflow_setdlt *)msg->data;
431 			if (set->iface >= NG_NETFLOW_MAXIFACES)
432 				ERROUT(EINVAL);
433 			iface = &priv->ifaces[set->iface];
434 
435 			/* connected iface? */
436 			if (iface->hook == NULL)
437 				ERROUT(EINVAL);
438 
439 			switch (set->dlt) {
440 			case	DLT_EN10MB:
441 				iface->info.ifinfo_dlt = DLT_EN10MB;
442 				break;
443 			case	DLT_RAW:
444 				iface->info.ifinfo_dlt = DLT_RAW;
445 				break;
446 			default:
447 				ERROUT(EINVAL);
448 			}
449 			break;
450 		    }
451 		case NGM_NETFLOW_SETIFINDEX:
452 		    {
453 			struct ng_netflow_setifindex *set;
454 			struct ng_netflow_iface *iface;
455 
456 			if (msg->header.arglen !=
457 			    sizeof(struct ng_netflow_setifindex))
458 				ERROUT(EINVAL);
459 
460 			set = (struct ng_netflow_setifindex *)msg->data;
461 			if (set->iface >= NG_NETFLOW_MAXIFACES)
462 				ERROUT(EINVAL);
463 			iface = &priv->ifaces[set->iface];
464 
465 			/* connected iface? */
466 			if (iface->hook == NULL)
467 				ERROUT(EINVAL);
468 
469 			iface->info.ifinfo_index = set->index;
470 
471 			break;
472 		    }
473 		case NGM_NETFLOW_SETTIMEOUTS:
474 		    {
475 			struct ng_netflow_settimeouts *set;
476 
477 			if (msg->header.arglen !=
478 			    sizeof(struct ng_netflow_settimeouts))
479 				ERROUT(EINVAL);
480 
481 			set = (struct ng_netflow_settimeouts *)msg->data;
482 
483 			priv->nfinfo_inact_t = set->inactive_timeout;
484 			priv->nfinfo_act_t = set->active_timeout;
485 
486 			break;
487 		    }
488 		case NGM_NETFLOW_SETCONFIG:
489 		    {
490 			struct ng_netflow_setconfig *set;
491 
492 			if (msg->header.arglen !=
493 			    sizeof(struct ng_netflow_setconfig))
494 				ERROUT(EINVAL);
495 
496 			set = (struct ng_netflow_setconfig *)msg->data;
497 
498 			if (set->iface >= NG_NETFLOW_MAXIFACES)
499 				ERROUT(EINVAL);
500 
501 			priv->ifaces[set->iface].info.conf = set->conf;
502 
503 			break;
504 		    }
505 		case NGM_NETFLOW_SETTEMPLATE:
506 		    {
507 			struct ng_netflow_settemplate *set;
508 
509 			if (msg->header.arglen !=
510 			    sizeof(struct ng_netflow_settemplate))
511 				ERROUT(EINVAL);
512 
513 			set = (struct ng_netflow_settemplate *)msg->data;
514 
515 			priv->templ_packets = set->packets;
516 			priv->templ_time = set->time;
517 
518 			break;
519 		    }
520 		case NGM_NETFLOW_SETMTU:
521 		    {
522 			struct ng_netflow_setmtu *set;
523 
524 			if (msg->header.arglen !=
525 			    sizeof(struct ng_netflow_setmtu))
526 				ERROUT(EINVAL);
527 
528 			set = (struct ng_netflow_setmtu *)msg->data;
529 			if ((set->mtu < MIN_MTU) || (set->mtu > MAX_MTU))
530 				ERROUT(EINVAL);
531 
532 			priv->mtu = set->mtu;
533 
534 			break;
535 		    }
536 		case NGM_NETFLOW_SHOW:
537 			if (msg->header.arglen !=
538 			    sizeof(struct ngnf_show_header))
539 				ERROUT(EINVAL);
540 
541 			NG_MKRESPONSE(resp, msg, NGRESP_SIZE, M_NOWAIT);
542 
543 			if (!resp)
544 				ERROUT(ENOMEM);
545 
546 			error = ng_netflow_flow_show(priv,
547 			    (struct ngnf_show_header *)msg->data,
548 			    (struct ngnf_show_header *)resp->data);
549 
550 			if (error)
551 				NG_FREE_MSG(resp);
552 
553 			break;
554 		case NGM_NETFLOW_V9INFO:
555 		    {
556 			struct ng_netflow_v9info *i;
557 
558 			NG_MKRESPONSE(resp, msg,
559 			    sizeof(struct ng_netflow_v9info), M_NOWAIT);
560 			i = (struct ng_netflow_v9info *)resp->data;
561 			ng_netflow_copyv9info(priv, i);
562 
563 			break;
564 		    }
565 		default:
566 			ERROUT(EINVAL);		/* unknown command */
567 			break;
568 		}
569 		break;
570 	default:
571 		ERROUT(EINVAL);		/* incorrect cookie */
572 		break;
573 	}
574 
575 	/*
576 	 * Take care of synchronous response, if any.
577 	 * Free memory and return.
578 	 */
579 done:
580 	NG_RESPOND_MSG(error, node, item, resp);
581 	NG_FREE_MSG(msg);
582 
583 	return (error);
584 }
585 
586 /* Receive data on hook. */
587 static int
588 ng_netflow_rcvdata (hook_p hook, item_p item)
589 {
590 	const node_p node = NG_HOOK_NODE(hook);
591 	const priv_p priv = NG_NODE_PRIVATE(node);
592 	const iface_p iface = NG_HOOK_PRIVATE(hook);
593 	hook_p out;
594 	struct mbuf *m = NULL, *m_old = NULL;
595 	struct ip *ip = NULL;
596 	struct ip6_hdr *ip6 = NULL;
597 	struct m_tag *mtag;
598 	int pullup_len = 0;
599 	uint8_t acct = 0, bypass = 0;
600 	int error = 0, l3_off = 0;
601 #if defined(INET) || defined(INET6)
602 	int off;
603 	uint8_t flags = 0, upper_proto = 0;
604 	unsigned int src_if_index;
605 	caddr_t upper_ptr = NULL;
606 #endif
607 	fib_export_p fe;
608 	uint32_t fib;
609 
610 	if ((hook == priv->export) || (hook == priv->export9)) {
611 		/*
612 		 * Data arrived on export hook.
613 		 * This must not happen.
614 		 */
615 		log(LOG_ERR, "ng_netflow: incoming data on export hook!\n");
616 		ERROUT(EINVAL);
617 	}
618 
619 	if (hook == iface->hook) {
620 		if ((iface->info.conf & NG_NETFLOW_CONF_INGRESS) == 0)
621 			bypass = 1;
622 		out = iface->out;
623 	} else if (hook == iface->out) {
624 		if ((iface->info.conf & NG_NETFLOW_CONF_EGRESS) == 0)
625 			bypass = 1;
626 		out = iface->hook;
627 	} else
628 		ERROUT(EINVAL);
629 
630 	if ((!bypass) && (iface->info.conf &
631 	    (NG_NETFLOW_CONF_ONCE | NG_NETFLOW_CONF_THISONCE))) {
632 		mtag = m_tag_locate(NGI_M(item), MTAG_NETFLOW,
633 		    MTAG_NETFLOW_CALLED, NULL);
634 		while (mtag != NULL) {
635 			if ((iface->info.conf & NG_NETFLOW_CONF_ONCE) ||
636 			    ((ng_ID_t *)(mtag + 1))[0] == NG_NODE_ID(node)) {
637 				bypass = 1;
638 				break;
639 			}
640 			mtag = m_tag_locate(NGI_M(item), MTAG_NETFLOW,
641 			    MTAG_NETFLOW_CALLED, mtag);
642 		}
643 	}
644 
645 	if (bypass) {
646 		if (out == NULL)
647 			ERROUT(ENOTCONN);
648 
649 		NG_FWD_ITEM_HOOK(error, item, out);
650 		return (error);
651 	}
652 
653 	if (iface->info.conf &
654 	    (NG_NETFLOW_CONF_ONCE | NG_NETFLOW_CONF_THISONCE)) {
655 		mtag = m_tag_alloc(MTAG_NETFLOW, MTAG_NETFLOW_CALLED,
656 		    sizeof(ng_ID_t), M_NOWAIT);
657 		if (mtag) {
658 			((ng_ID_t *)(mtag + 1))[0] = NG_NODE_ID(node);
659 			m_tag_prepend(NGI_M(item), mtag);
660 		}
661 	}
662 
663 #if defined(INET) || defined(INET6)
664 	/* Import configuration flags related to flow creation */
665 	flags = iface->info.conf & NG_NETFLOW_FLOW_FLAGS;
666 #endif
667 
668 	NGI_GET_M(item, m);
669 	m_old = m;
670 
671 	/* Increase counters. */
672 	iface->info.ifinfo_packets++;
673 
674 	/*
675 	 * Depending on interface data link type and packet contents
676 	 * we pullup enough data, so that ng_netflow_flow_add() does not
677 	 * need to know about mbuf at all. We keep current length of data
678 	 * needed to be contiguous in pullup_len. mtod() is done at the
679 	 * very end one more time, since m can had changed after pulluping.
680 	 *
681 	 * In case of unrecognized data we don't return error, but just
682 	 * pass data to downstream hook, if it is available.
683 	 */
684 
685 #define	M_CHECK(length)	do {					\
686 	pullup_len += length;					\
687 	if (((m)->m_pkthdr.len < (pullup_len)) ||		\
688 	   ((pullup_len) > MHLEN)) {				\
689 		error = EINVAL;					\
690 		goto bypass;					\
691 	} 							\
692 	if ((m)->m_len < (pullup_len) &&			\
693 	   (((m) = m_pullup((m),(pullup_len))) == NULL)) {	\
694 		error = ENOBUFS;				\
695 		goto done;					\
696 	}							\
697 } while (0)
698 
699 	switch (iface->info.ifinfo_dlt) {
700 	case DLT_EN10MB:	/* Ethernet */
701 	    {
702 		struct ether_header *eh;
703 		uint16_t etype;
704 
705 		M_CHECK(sizeof(struct ether_header));
706 		eh = mtod(m, struct ether_header *);
707 
708 		/* Make sure this is IP frame. */
709 		etype = ntohs(eh->ether_type);
710 		switch (etype) {
711 #ifdef INET
712 		case ETHERTYPE_IP:
713 			M_CHECK(sizeof(struct ip));
714 			eh = mtod(m, struct ether_header *);
715 			ip = (struct ip *)(eh + 1);
716 			l3_off = sizeof(struct ether_header);
717 			break;
718 #endif
719 #ifdef INET6
720 		case ETHERTYPE_IPV6:
721 			/*
722 			 * m_pullup() called by M_CHECK() pullups
723 			 * kern.ipc.max_protohdr (default 60 bytes)
724 			 * which is enough.
725 			 */
726 			M_CHECK(sizeof(struct ip6_hdr));
727 			eh = mtod(m, struct ether_header *);
728 			ip6 = (struct ip6_hdr *)(eh + 1);
729 			l3_off = sizeof(struct ether_header);
730 			break;
731 #endif
732 		case ETHERTYPE_VLAN:
733 		    {
734 			struct ether_vlan_header *evh;
735 
736 			M_CHECK(sizeof(struct ether_vlan_header) -
737 			    sizeof(struct ether_header));
738 			evh = mtod(m, struct ether_vlan_header *);
739 			etype = ntohs(evh->evl_proto);
740 			l3_off = sizeof(struct ether_vlan_header);
741 
742 			if (etype == ETHERTYPE_IP) {
743 #ifdef INET
744 				M_CHECK(sizeof(struct ip));
745 				ip = (struct ip *)(evh + 1);
746 				break;
747 #endif
748 #ifdef INET6
749 			} else if (etype == ETHERTYPE_IPV6) {
750 				M_CHECK(sizeof(struct ip6_hdr));
751 				ip6 = (struct ip6_hdr *)(evh + 1);
752 				break;
753 #endif
754 			}
755 		    }
756 		default:
757 			goto bypass;	/* pass this frame */
758 		}
759 		break;
760 	    }
761 	case DLT_RAW:		/* IP packets */
762 		M_CHECK(sizeof(struct ip));
763 		ip = mtod(m, struct ip *);
764 		/* l3_off is already zero */
765 #ifdef INET6
766 		/*
767 		 * If INET6 is not defined IPv6 packets
768 		 * will be discarded in ng_netflow_flow_add().
769 		 */
770 		if (ip->ip_v == IP6VERSION) {
771 			ip = NULL;
772 			M_CHECK(sizeof(struct ip6_hdr) - sizeof(struct ip));
773 			ip6 = mtod(m, struct ip6_hdr *);
774 		}
775 #endif
776 #ifndef INET
777 		ip = NULL;
778 #endif
779 		break;
780 	default:
781 		goto bypass;
782 		break;
783 	}
784 
785 #if defined(INET) || defined(INET6)
786 	off = pullup_len;
787 #endif
788 
789 	if ((ip != NULL) && ((ip->ip_off & htons(IP_OFFMASK)) == 0)) {
790 		if ((ip->ip_v != IPVERSION) ||
791 		    ((ip->ip_hl << 2) < sizeof(struct ip)))
792 			goto bypass;
793 		/*
794 		 * In case of IPv4 header with options, we haven't pulled
795 		 * up enough, yet.
796 		 */
797 		M_CHECK((ip->ip_hl << 2) - sizeof(struct ip));
798 
799 #if defined(INET) || defined(INET6)
800 		/* Save upper layer offset and proto */
801 		off = pullup_len;
802 		upper_proto = ip->ip_p;
803 #endif
804 
805 		/*
806 		 * XXX: in case of wrong upper layer header we will
807 		 * forward this packet but skip this record in netflow.
808 		 */
809 		switch (ip->ip_p) {
810 		case IPPROTO_TCP:
811 			M_CHECK(sizeof(struct tcphdr));
812 			break;
813 		case IPPROTO_UDP:
814 			M_CHECK(sizeof(struct udphdr));
815 			break;
816 		case IPPROTO_SCTP:
817 			M_CHECK(sizeof(struct sctphdr));
818 			break;
819 		}
820 	} else if (ip != NULL) {
821 		/*
822 		 * Nothing to save except upper layer proto,
823 		 * since this is a packet fragment.
824 		 */
825 #if defined(INET) || defined(INET6)
826 		flags |= NG_NETFLOW_IS_FRAG;
827 		upper_proto = ip->ip_p;
828 #endif
829 		if ((ip->ip_v != IPVERSION) ||
830 		    ((ip->ip_hl << 2) < sizeof(struct ip)))
831 			goto bypass;
832 #ifdef INET6
833 	} else if (ip6 != NULL) {
834 		int cur = ip6->ip6_nxt, hdr_off = 0;
835 		struct ip6_ext *ip6e;
836 		struct ip6_frag *ip6f;
837 
838 		if (priv->export9 == NULL)
839 			goto bypass;
840 
841 		/* Save upper layer info. */
842 		off = pullup_len;
843 		upper_proto = cur;
844 
845 		if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION)
846 			goto bypass;
847 
848 		/*
849 		 * Loop through IPv6 extended headers to get upper
850 		 * layer header / frag.
851 		 */
852 		for (;;) {
853 			switch (cur) {
854 			/*
855 			 * Same as in IPv4, we can forward a 'bad'
856 			 * packet without accounting.
857 			 */
858 			case IPPROTO_TCP:
859 				M_CHECK(sizeof(struct tcphdr));
860 				goto loopend;
861 			case IPPROTO_UDP:
862 				M_CHECK(sizeof(struct udphdr));
863 				goto loopend;
864 			case IPPROTO_SCTP:
865 				M_CHECK(sizeof(struct sctphdr));
866 				goto loopend;
867 
868 			/* Loop until 'real' upper layer headers */
869 			case IPPROTO_HOPOPTS:
870 			case IPPROTO_ROUTING:
871 			case IPPROTO_DSTOPTS:
872 				M_CHECK(sizeof(struct ip6_ext));
873 				ip6e = (struct ip6_ext *)(mtod(m, caddr_t) +
874 				    off);
875 				upper_proto = ip6e->ip6e_nxt;
876 				hdr_off = (ip6e->ip6e_len + 1) << 3;
877 				break;
878 
879 			/* RFC4302, can be before DSTOPTS */
880 			case IPPROTO_AH:
881 				M_CHECK(sizeof(struct ip6_ext));
882 				ip6e = (struct ip6_ext *)(mtod(m, caddr_t) +
883 				    off);
884 				upper_proto = ip6e->ip6e_nxt;
885 				hdr_off = (ip6e->ip6e_len + 2) << 2;
886 				break;
887 
888 			case IPPROTO_FRAGMENT:
889 				M_CHECK(sizeof(struct ip6_frag));
890 				ip6f = (struct ip6_frag *)(mtod(m, caddr_t) +
891 				    off);
892 				upper_proto = ip6f->ip6f_nxt;
893 				hdr_off = sizeof(struct ip6_frag);
894 				off += hdr_off;
895 				flags |= NG_NETFLOW_IS_FRAG;
896 				goto loopend;
897 
898 #if 0
899 			case IPPROTO_NONE:
900 				goto loopend;
901 #endif
902 			/*
903 			 * Any unknown header (new extension or IPv6/IPv4
904 			 * header for tunnels) ends loop.
905 			 */
906 			default:
907 				goto loopend;
908 			}
909 
910 			off += hdr_off;
911 			cur = upper_proto;
912 		}
913 #endif
914 	}
915 #undef	M_CHECK
916 
917 #ifdef INET6
918 loopend:
919 #endif
920 	/* Just in case of real reallocation in M_CHECK() / m_pullup() */
921 	if (m != m_old) {
922 		priv->nfinfo_realloc_mbuf++;
923 		/* Restore ip/ipv6 pointer */
924 		if (ip != NULL)
925 			ip = (struct ip *)(mtod(m, caddr_t) + l3_off);
926 		else if (ip6 != NULL)
927 			ip6 = (struct ip6_hdr *)(mtod(m, caddr_t) + l3_off);
928  	}
929 
930 #if defined(INET) || defined(INET6)
931 	upper_ptr = (caddr_t)(mtod(m, caddr_t) + off);
932 
933 	/* Determine packet input interface. Prefer configured. */
934 	src_if_index = 0;
935 	if (hook == iface->out || iface->info.ifinfo_index == 0) {
936 		if (m->m_pkthdr.rcvif != NULL)
937 			src_if_index = m->m_pkthdr.rcvif->if_index;
938 	} else
939 		src_if_index = iface->info.ifinfo_index;
940 #endif
941 
942 	/* Check packet FIB */
943 	fib = M_GETFIB(m);
944 	if (fib >= priv->maxfibs) {
945 		CTR2(KTR_NET, "ng_netflow_rcvdata(): packet fib %d is out of "
946 		    "range of available fibs: 0 .. %d",
947 		    fib, priv->maxfibs);
948 		goto bypass;
949 	}
950 
951 	if ((fe = priv_to_fib(priv, fib)) == NULL) {
952 		/* Setup new FIB */
953 		if (ng_netflow_fib_init(priv, fib) != 0) {
954 			/* malloc() failed */
955 			goto bypass;
956 		}
957 
958 		fe = priv_to_fib(priv, fib);
959 	}
960 
961 #ifdef INET
962 	if (ip != NULL)
963 		error = ng_netflow_flow_add(priv, fe, ip, upper_ptr,
964 		    upper_proto, flags, src_if_index);
965 #endif
966 #if defined(INET6) && defined(INET)
967 	else
968 #endif
969 #ifdef INET6
970 	if (ip6 != NULL)
971 		error = ng_netflow_flow6_add(priv, fe, ip6, upper_ptr,
972 		    upper_proto, flags, src_if_index);
973 #endif
974 	else
975 		goto bypass;
976 
977 	acct = 1;
978 bypass:
979 	if (out != NULL) {
980 		if (acct == 0) {
981 			/* Accounting failure */
982 			if (ip != NULL) {
983 				counter_u64_add(priv->nfinfo_spackets, 1);
984 				counter_u64_add(priv->nfinfo_sbytes,
985 				    m->m_pkthdr.len);
986 			} else if (ip6 != NULL) {
987 				counter_u64_add(priv->nfinfo_spackets6, 1);
988 				counter_u64_add(priv->nfinfo_sbytes6,
989 				    m->m_pkthdr.len);
990 			}
991 		}
992 
993 		/* XXX: error gets overwritten here */
994 		NG_FWD_NEW_DATA(error, item, out, m);
995 		return (error);
996 	}
997 done:
998 	if (item)
999 		NG_FREE_ITEM(item);
1000 	if (m)
1001 		NG_FREE_M(m);
1002 
1003 	return (error);
1004 }
1005 
1006 /* We will be shut down in a moment */
1007 static int
1008 ng_netflow_close(node_p node)
1009 {
1010 	const priv_p priv = NG_NODE_PRIVATE(node);
1011 
1012 	callout_drain(&priv->exp_callout);
1013 	ng_netflow_cache_flush(priv);
1014 
1015 	return (0);
1016 }
1017 
1018 /* Do local shutdown processing. */
1019 static int
1020 ng_netflow_rmnode(node_p node)
1021 {
1022 	const priv_p priv = NG_NODE_PRIVATE(node);
1023 
1024 	NG_NODE_SET_PRIVATE(node, NULL);
1025 	NG_NODE_UNREF(priv->node);
1026 
1027 	free(priv->fib_data, M_NETGRAPH);
1028 	free(priv, M_NETGRAPH);
1029 
1030 	return (0);
1031 }
1032 
1033 /* Hook disconnection. */
1034 static int
1035 ng_netflow_disconnect(hook_p hook)
1036 {
1037 	node_p node = NG_HOOK_NODE(hook);
1038 	priv_p priv = NG_NODE_PRIVATE(node);
1039 	iface_p iface = NG_HOOK_PRIVATE(hook);
1040 
1041 	if (iface != NULL) {
1042 		if (iface->hook == hook)
1043 			iface->hook = NULL;
1044 		if (iface->out == hook)
1045 			iface->out = NULL;
1046 	}
1047 
1048 	/* if export hook disconnected stop running expire(). */
1049 	if (hook == priv->export) {
1050 		if (priv->export9 == NULL)
1051 			callout_drain(&priv->exp_callout);
1052 		priv->export = NULL;
1053 	}
1054 
1055 	if (hook == priv->export9) {
1056 		if (priv->export == NULL)
1057 			callout_drain(&priv->exp_callout);
1058 		priv->export9 = NULL;
1059 	}
1060 
1061 	/* Removal of the last link destroys the node. */
1062 	if (NG_NODE_NUMHOOKS(node) == 0)
1063 		ng_rmnode_self(node);
1064 
1065 	return (0);
1066 }
1067