xref: /freebsd/sys/netgraph/netflow/ng_netflow.c (revision 325151a3)
1 /*-
2  * Copyright (c) 2010-2011 Alexander V. Chernikov <melifaro@ipfw.ru>
3  * Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org>
4  * Copyright (c) 2001-2003 Roman V. Palagin <romanp@unshadow.net>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $SourceForge: ng_netflow.c,v 1.30 2004/09/05 11:37:43 glebius Exp $
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include "opt_inet6.h"
35 #include "opt_route.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/counter.h>
40 #include <sys/kernel.h>
41 #include <sys/limits.h>
42 #include <sys/mbuf.h>
43 #include <sys/socket.h>
44 #include <sys/syslog.h>
45 #include <sys/ctype.h>
46 
47 #include <net/if.h>
48 #include <net/ethernet.h>
49 #include <net/route.h>
50 #include <net/if_arp.h>
51 #include <net/if_var.h>
52 #include <net/if_vlan_var.h>
53 #include <net/bpf.h>
54 #include <netinet/in.h>
55 #include <netinet/in_systm.h>
56 #include <netinet/ip.h>
57 #include <netinet/ip6.h>
58 #include <netinet/tcp.h>
59 #include <netinet/udp.h>
60 #include <netinet/sctp.h>
61 
62 #include <netgraph/ng_message.h>
63 #include <netgraph/ng_parse.h>
64 #include <netgraph/netgraph.h>
65 #include <netgraph/netflow/netflow.h>
66 #include <netgraph/netflow/netflow_v9.h>
67 #include <netgraph/netflow/ng_netflow.h>
68 
69 /* Netgraph methods */
70 static ng_constructor_t	ng_netflow_constructor;
71 static ng_rcvmsg_t	ng_netflow_rcvmsg;
72 static ng_close_t	ng_netflow_close;
73 static ng_shutdown_t	ng_netflow_rmnode;
74 static ng_newhook_t	ng_netflow_newhook;
75 static ng_rcvdata_t	ng_netflow_rcvdata;
76 static ng_disconnect_t	ng_netflow_disconnect;
77 
78 /* Parse type for struct ng_netflow_info */
79 static const struct ng_parse_struct_field ng_netflow_info_type_fields[]
80 	= NG_NETFLOW_INFO_TYPE;
81 static const struct ng_parse_type ng_netflow_info_type = {
82 	&ng_parse_struct_type,
83 	&ng_netflow_info_type_fields
84 };
85 
86 /*  Parse type for struct ng_netflow_ifinfo */
87 static const struct ng_parse_struct_field ng_netflow_ifinfo_type_fields[]
88 	= NG_NETFLOW_IFINFO_TYPE;
89 static const struct ng_parse_type ng_netflow_ifinfo_type = {
90 	&ng_parse_struct_type,
91 	&ng_netflow_ifinfo_type_fields
92 };
93 
94 /* Parse type for struct ng_netflow_setdlt */
95 static const struct ng_parse_struct_field ng_netflow_setdlt_type_fields[]
96 	= NG_NETFLOW_SETDLT_TYPE;
97 static const struct ng_parse_type ng_netflow_setdlt_type = {
98 	&ng_parse_struct_type,
99 	&ng_netflow_setdlt_type_fields
100 };
101 
102 /* Parse type for ng_netflow_setifindex */
103 static const struct ng_parse_struct_field ng_netflow_setifindex_type_fields[]
104 	= NG_NETFLOW_SETIFINDEX_TYPE;
105 static const struct ng_parse_type ng_netflow_setifindex_type = {
106 	&ng_parse_struct_type,
107 	&ng_netflow_setifindex_type_fields
108 };
109 
110 /* Parse type for ng_netflow_settimeouts */
111 static const struct ng_parse_struct_field ng_netflow_settimeouts_type_fields[]
112 	= NG_NETFLOW_SETTIMEOUTS_TYPE;
113 static const struct ng_parse_type ng_netflow_settimeouts_type = {
114 	&ng_parse_struct_type,
115 	&ng_netflow_settimeouts_type_fields
116 };
117 
118 /* Parse type for ng_netflow_setconfig */
119 static const struct ng_parse_struct_field ng_netflow_setconfig_type_fields[]
120 	= NG_NETFLOW_SETCONFIG_TYPE;
121 static const struct ng_parse_type ng_netflow_setconfig_type = {
122 	&ng_parse_struct_type,
123 	&ng_netflow_setconfig_type_fields
124 };
125 
126 /* Parse type for ng_netflow_settemplate */
127 static const struct ng_parse_struct_field ng_netflow_settemplate_type_fields[]
128 	= NG_NETFLOW_SETTEMPLATE_TYPE;
129 static const struct ng_parse_type ng_netflow_settemplate_type = {
130 	&ng_parse_struct_type,
131 	&ng_netflow_settemplate_type_fields
132 };
133 
134 /* Parse type for ng_netflow_setmtu */
135 static const struct ng_parse_struct_field ng_netflow_setmtu_type_fields[]
136 	= NG_NETFLOW_SETMTU_TYPE;
137 static const struct ng_parse_type ng_netflow_setmtu_type = {
138 	&ng_parse_struct_type,
139 	&ng_netflow_setmtu_type_fields
140 };
141 
142 /* Parse type for struct ng_netflow_v9info */
143 static const struct ng_parse_struct_field ng_netflow_v9info_type_fields[]
144 	= NG_NETFLOW_V9INFO_TYPE;
145 static const struct ng_parse_type ng_netflow_v9info_type = {
146 	&ng_parse_struct_type,
147 	&ng_netflow_v9info_type_fields
148 };
149 
150 /* List of commands and how to convert arguments to/from ASCII */
151 static const struct ng_cmdlist ng_netflow_cmds[] = {
152        {
153 	 NGM_NETFLOW_COOKIE,
154 	 NGM_NETFLOW_INFO,
155 	 "info",
156 	 NULL,
157 	 &ng_netflow_info_type
158        },
159        {
160 	NGM_NETFLOW_COOKIE,
161 	NGM_NETFLOW_IFINFO,
162 	"ifinfo",
163 	&ng_parse_uint16_type,
164 	&ng_netflow_ifinfo_type
165        },
166        {
167 	NGM_NETFLOW_COOKIE,
168 	NGM_NETFLOW_SETDLT,
169 	"setdlt",
170 	&ng_netflow_setdlt_type,
171 	NULL
172        },
173        {
174 	NGM_NETFLOW_COOKIE,
175 	NGM_NETFLOW_SETIFINDEX,
176 	"setifindex",
177 	&ng_netflow_setifindex_type,
178 	NULL
179        },
180        {
181 	NGM_NETFLOW_COOKIE,
182 	NGM_NETFLOW_SETTIMEOUTS,
183 	"settimeouts",
184 	&ng_netflow_settimeouts_type,
185 	NULL
186        },
187        {
188 	NGM_NETFLOW_COOKIE,
189 	NGM_NETFLOW_SETCONFIG,
190 	"setconfig",
191 	&ng_netflow_setconfig_type,
192 	NULL
193        },
194        {
195 	NGM_NETFLOW_COOKIE,
196 	NGM_NETFLOW_SETTEMPLATE,
197 	"settemplate",
198 	&ng_netflow_settemplate_type,
199 	NULL
200        },
201        {
202 	NGM_NETFLOW_COOKIE,
203 	NGM_NETFLOW_SETMTU,
204 	"setmtu",
205 	&ng_netflow_setmtu_type,
206 	NULL
207        },
208        {
209 	 NGM_NETFLOW_COOKIE,
210 	 NGM_NETFLOW_V9INFO,
211 	 "v9info",
212 	 NULL,
213 	 &ng_netflow_v9info_type
214        },
215        { 0 }
216 };
217 
218 
219 /* Netgraph node type descriptor */
220 static struct ng_type ng_netflow_typestruct = {
221 	.version =	NG_ABI_VERSION,
222 	.name =		NG_NETFLOW_NODE_TYPE,
223 	.constructor =	ng_netflow_constructor,
224 	.rcvmsg =	ng_netflow_rcvmsg,
225 	.close =	ng_netflow_close,
226 	.shutdown =	ng_netflow_rmnode,
227 	.newhook =	ng_netflow_newhook,
228 	.rcvdata =	ng_netflow_rcvdata,
229 	.disconnect =	ng_netflow_disconnect,
230 	.cmdlist =	ng_netflow_cmds,
231 };
232 NETGRAPH_INIT(netflow, &ng_netflow_typestruct);
233 
234 /* Called at node creation */
235 static int
236 ng_netflow_constructor(node_p node)
237 {
238 	priv_p priv;
239 	int i;
240 
241 	/* Initialize private data */
242 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO);
243 
244 	/* Initialize fib data */
245 	priv->maxfibs = rt_numfibs;
246 	priv->fib_data = malloc(sizeof(fib_export_p) * priv->maxfibs,
247 	    M_NETGRAPH, M_WAITOK | M_ZERO);
248 
249 	/* Make node and its data point at each other */
250 	NG_NODE_SET_PRIVATE(node, priv);
251 	priv->node = node;
252 
253 	/* Initialize timeouts to default values */
254 	priv->nfinfo_inact_t = INACTIVE_TIMEOUT;
255 	priv->nfinfo_act_t = ACTIVE_TIMEOUT;
256 
257 	/* Set default config */
258 	for (i = 0; i < NG_NETFLOW_MAXIFACES; i++)
259 		priv->ifaces[i].info.conf = NG_NETFLOW_CONF_INGRESS;
260 
261 	/* Initialize callout handle */
262 	callout_init(&priv->exp_callout, 1);
263 
264 	/* Allocate memory and set up flow cache */
265 	ng_netflow_cache_init(priv);
266 
267 	return (0);
268 }
269 
270 /*
271  * ng_netflow supports two hooks: data and export.
272  * Incoming traffic is expected on data, and expired
273  * netflow datagrams are sent to export.
274  */
275 static int
276 ng_netflow_newhook(node_p node, hook_p hook, const char *name)
277 {
278 	const priv_p priv = NG_NODE_PRIVATE(node);
279 
280 	if (strncmp(name, NG_NETFLOW_HOOK_DATA,	/* an iface hook? */
281 	    strlen(NG_NETFLOW_HOOK_DATA)) == 0) {
282 		iface_p iface;
283 		int ifnum = -1;
284 		const char *cp;
285 		char *eptr;
286 
287 		cp = name + strlen(NG_NETFLOW_HOOK_DATA);
288 		if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
289 			return (EINVAL);
290 
291 		ifnum = (int)strtoul(cp, &eptr, 10);
292 		if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
293 			return (EINVAL);
294 
295 		/* See if hook is already connected */
296 		if (priv->ifaces[ifnum].hook != NULL)
297 			return (EISCONN);
298 
299 		iface = &priv->ifaces[ifnum];
300 
301 		/* Link private info and hook together */
302 		NG_HOOK_SET_PRIVATE(hook, iface);
303 		iface->hook = hook;
304 
305 		/*
306 		 * In most cases traffic accounting is done on an
307 		 * Ethernet interface, so default data link type
308 		 * will be DLT_EN10MB.
309 		 */
310 		iface->info.ifinfo_dlt = DLT_EN10MB;
311 
312 	} else if (strncmp(name, NG_NETFLOW_HOOK_OUT,
313 	    strlen(NG_NETFLOW_HOOK_OUT)) == 0) {
314 		iface_p iface;
315 		int ifnum = -1;
316 		const char *cp;
317 		char *eptr;
318 
319 		cp = name + strlen(NG_NETFLOW_HOOK_OUT);
320 		if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
321 			return (EINVAL);
322 
323 		ifnum = (int)strtoul(cp, &eptr, 10);
324 		if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
325 			return (EINVAL);
326 
327 		/* See if hook is already connected */
328 		if (priv->ifaces[ifnum].out != NULL)
329 			return (EISCONN);
330 
331 		iface = &priv->ifaces[ifnum];
332 
333 		/* Link private info and hook together */
334 		NG_HOOK_SET_PRIVATE(hook, iface);
335 		iface->out = hook;
336 
337 	} else if (strcmp(name, NG_NETFLOW_HOOK_EXPORT) == 0) {
338 
339 		if (priv->export != NULL)
340 			return (EISCONN);
341 
342 		/* Netflow version 5 supports 32-bit counters only */
343 		if (CNTR_MAX == UINT64_MAX)
344 			return (EINVAL);
345 
346 		priv->export = hook;
347 
348 		/* Exporter is ready. Let's schedule expiry. */
349 		callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire,
350 		    (void *)priv);
351 	} else if (strcmp(name, NG_NETFLOW_HOOK_EXPORT9) == 0) {
352 
353 		if (priv->export9 != NULL)
354 			return (EISCONN);
355 
356 		priv->export9 = hook;
357 
358 		/* Exporter is ready. Let's schedule expiry. */
359 		callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire,
360 		    (void *)priv);
361 	} else
362 		return (EINVAL);
363 
364 	return (0);
365 }
366 
367 /* Get a netgraph control message. */
368 static int
369 ng_netflow_rcvmsg (node_p node, item_p item, hook_p lasthook)
370 {
371 	const priv_p priv = NG_NODE_PRIVATE(node);
372 	struct ng_mesg *resp = NULL;
373 	int error = 0;
374 	struct ng_mesg *msg;
375 
376 	NGI_GET_MSG(item, msg);
377 
378 	/* Deal with message according to cookie and command */
379 	switch (msg->header.typecookie) {
380 	case NGM_NETFLOW_COOKIE:
381 		switch (msg->header.cmd) {
382 		case NGM_NETFLOW_INFO:
383 		    {
384 			struct ng_netflow_info *i;
385 
386 			NG_MKRESPONSE(resp, msg, sizeof(struct ng_netflow_info),
387 			    M_NOWAIT);
388 			i = (struct ng_netflow_info *)resp->data;
389 			ng_netflow_copyinfo(priv, i);
390 
391 			break;
392 		    }
393 		case NGM_NETFLOW_IFINFO:
394 		    {
395 			struct ng_netflow_ifinfo *i;
396 			const uint16_t *index;
397 
398 			if (msg->header.arglen != sizeof(uint16_t))
399 				 ERROUT(EINVAL);
400 
401 			index  = (uint16_t *)msg->data;
402 			if (*index >= NG_NETFLOW_MAXIFACES)
403 				ERROUT(EINVAL);
404 
405 			/* connected iface? */
406 			if (priv->ifaces[*index].hook == NULL)
407 				 ERROUT(EINVAL);
408 
409 			NG_MKRESPONSE(resp, msg,
410 			     sizeof(struct ng_netflow_ifinfo), M_NOWAIT);
411 			i = (struct ng_netflow_ifinfo *)resp->data;
412 			memcpy((void *)i, (void *)&priv->ifaces[*index].info,
413 			    sizeof(priv->ifaces[*index].info));
414 
415 			break;
416 		    }
417 		case NGM_NETFLOW_SETDLT:
418 		    {
419 			struct ng_netflow_setdlt *set;
420 			struct ng_netflow_iface *iface;
421 
422 			if (msg->header.arglen !=
423 			    sizeof(struct ng_netflow_setdlt))
424 				ERROUT(EINVAL);
425 
426 			set = (struct ng_netflow_setdlt *)msg->data;
427 			if (set->iface >= NG_NETFLOW_MAXIFACES)
428 				ERROUT(EINVAL);
429 			iface = &priv->ifaces[set->iface];
430 
431 			/* connected iface? */
432 			if (iface->hook == NULL)
433 				ERROUT(EINVAL);
434 
435 			switch (set->dlt) {
436 			case	DLT_EN10MB:
437 				iface->info.ifinfo_dlt = DLT_EN10MB;
438 				break;
439 			case	DLT_RAW:
440 				iface->info.ifinfo_dlt = DLT_RAW;
441 				break;
442 			default:
443 				ERROUT(EINVAL);
444 			}
445 			break;
446 		    }
447 		case NGM_NETFLOW_SETIFINDEX:
448 		    {
449 			struct ng_netflow_setifindex *set;
450 			struct ng_netflow_iface *iface;
451 
452 			if (msg->header.arglen !=
453 			    sizeof(struct ng_netflow_setifindex))
454 				ERROUT(EINVAL);
455 
456 			set = (struct ng_netflow_setifindex *)msg->data;
457 			if (set->iface >= NG_NETFLOW_MAXIFACES)
458 				ERROUT(EINVAL);
459 			iface = &priv->ifaces[set->iface];
460 
461 			/* connected iface? */
462 			if (iface->hook == NULL)
463 				ERROUT(EINVAL);
464 
465 			iface->info.ifinfo_index = set->index;
466 
467 			break;
468 		    }
469 		case NGM_NETFLOW_SETTIMEOUTS:
470 		    {
471 			struct ng_netflow_settimeouts *set;
472 
473 			if (msg->header.arglen !=
474 			    sizeof(struct ng_netflow_settimeouts))
475 				ERROUT(EINVAL);
476 
477 			set = (struct ng_netflow_settimeouts *)msg->data;
478 
479 			priv->nfinfo_inact_t = set->inactive_timeout;
480 			priv->nfinfo_act_t = set->active_timeout;
481 
482 			break;
483 		    }
484 		case NGM_NETFLOW_SETCONFIG:
485 		    {
486 			struct ng_netflow_setconfig *set;
487 
488 			if (msg->header.arglen !=
489 			    sizeof(struct ng_netflow_setconfig))
490 				ERROUT(EINVAL);
491 
492 			set = (struct ng_netflow_setconfig *)msg->data;
493 
494 			if (set->iface >= NG_NETFLOW_MAXIFACES)
495 				ERROUT(EINVAL);
496 
497 			priv->ifaces[set->iface].info.conf = set->conf;
498 
499 			break;
500 		    }
501 		case NGM_NETFLOW_SETTEMPLATE:
502 		    {
503 			struct ng_netflow_settemplate *set;
504 
505 			if (msg->header.arglen !=
506 			    sizeof(struct ng_netflow_settemplate))
507 				ERROUT(EINVAL);
508 
509 			set = (struct ng_netflow_settemplate *)msg->data;
510 
511 			priv->templ_packets = set->packets;
512 			priv->templ_time = set->time;
513 
514 			break;
515 		    }
516 		case NGM_NETFLOW_SETMTU:
517 		    {
518 			struct ng_netflow_setmtu *set;
519 
520 			if (msg->header.arglen !=
521 			    sizeof(struct ng_netflow_setmtu))
522 				ERROUT(EINVAL);
523 
524 			set = (struct ng_netflow_setmtu *)msg->data;
525 			if ((set->mtu < MIN_MTU) || (set->mtu > MAX_MTU))
526 				ERROUT(EINVAL);
527 
528 			priv->mtu = set->mtu;
529 
530 			break;
531 		    }
532 		case NGM_NETFLOW_SHOW:
533 			if (msg->header.arglen !=
534 			    sizeof(struct ngnf_show_header))
535 				ERROUT(EINVAL);
536 
537 			NG_MKRESPONSE(resp, msg, NGRESP_SIZE, M_NOWAIT);
538 
539 			if (!resp)
540 				ERROUT(ENOMEM);
541 
542 			error = ng_netflow_flow_show(priv,
543 			    (struct ngnf_show_header *)msg->data,
544 			    (struct ngnf_show_header *)resp->data);
545 
546 			if (error)
547 				NG_FREE_MSG(resp);
548 
549 			break;
550 		case NGM_NETFLOW_V9INFO:
551 		    {
552 			struct ng_netflow_v9info *i;
553 
554 			NG_MKRESPONSE(resp, msg,
555 			    sizeof(struct ng_netflow_v9info), M_NOWAIT);
556 			i = (struct ng_netflow_v9info *)resp->data;
557 			ng_netflow_copyv9info(priv, i);
558 
559 			break;
560 		    }
561 		default:
562 			ERROUT(EINVAL);		/* unknown command */
563 			break;
564 		}
565 		break;
566 	default:
567 		ERROUT(EINVAL);		/* incorrect cookie */
568 		break;
569 	}
570 
571 	/*
572 	 * Take care of synchronous response, if any.
573 	 * Free memory and return.
574 	 */
575 done:
576 	NG_RESPOND_MSG(error, node, item, resp);
577 	NG_FREE_MSG(msg);
578 
579 	return (error);
580 }
581 
582 /* Receive data on hook. */
583 static int
584 ng_netflow_rcvdata (hook_p hook, item_p item)
585 {
586 	const node_p node = NG_HOOK_NODE(hook);
587 	const priv_p priv = NG_NODE_PRIVATE(node);
588 	const iface_p iface = NG_HOOK_PRIVATE(hook);
589 	hook_p out;
590 	struct mbuf *m = NULL, *m_old = NULL;
591 	struct ip *ip = NULL;
592 	struct ip6_hdr *ip6 = NULL;
593 	struct m_tag *mtag;
594 	int pullup_len = 0, off;
595 	uint8_t acct = 0, bypass = 0, flags = 0, upper_proto = 0;
596 	int error = 0, l3_off = 0;
597 	unsigned int src_if_index;
598 	caddr_t upper_ptr = NULL;
599 	fib_export_p fe;
600 	uint32_t fib;
601 
602 	if ((hook == priv->export) || (hook == priv->export9)) {
603 		/*
604 		 * Data arrived on export hook.
605 		 * This must not happen.
606 		 */
607 		log(LOG_ERR, "ng_netflow: incoming data on export hook!\n");
608 		ERROUT(EINVAL);
609 	};
610 
611 	if (hook == iface->hook) {
612 		if ((iface->info.conf & NG_NETFLOW_CONF_INGRESS) == 0)
613 			bypass = 1;
614 		out = iface->out;
615 	} else if (hook == iface->out) {
616 		if ((iface->info.conf & NG_NETFLOW_CONF_EGRESS) == 0)
617 			bypass = 1;
618 		out = iface->hook;
619 	} else
620 		ERROUT(EINVAL);
621 
622 	if ((!bypass) && (iface->info.conf &
623 	    (NG_NETFLOW_CONF_ONCE | NG_NETFLOW_CONF_THISONCE))) {
624 		mtag = m_tag_locate(NGI_M(item), MTAG_NETFLOW,
625 		    MTAG_NETFLOW_CALLED, NULL);
626 		while (mtag != NULL) {
627 			if ((iface->info.conf & NG_NETFLOW_CONF_ONCE) ||
628 			    ((ng_ID_t *)(mtag + 1))[0] == NG_NODE_ID(node)) {
629 				bypass = 1;
630 				break;
631 			}
632 			mtag = m_tag_locate(NGI_M(item), MTAG_NETFLOW,
633 			    MTAG_NETFLOW_CALLED, mtag);
634 		}
635 	}
636 
637 	if (bypass) {
638 		if (out == NULL)
639 			ERROUT(ENOTCONN);
640 
641 		NG_FWD_ITEM_HOOK(error, item, out);
642 		return (error);
643 	}
644 
645 	if (iface->info.conf &
646 	    (NG_NETFLOW_CONF_ONCE | NG_NETFLOW_CONF_THISONCE)) {
647 		mtag = m_tag_alloc(MTAG_NETFLOW, MTAG_NETFLOW_CALLED,
648 		    sizeof(ng_ID_t), M_NOWAIT);
649 		if (mtag) {
650 			((ng_ID_t *)(mtag + 1))[0] = NG_NODE_ID(node);
651 			m_tag_prepend(NGI_M(item), mtag);
652 		}
653 	}
654 
655 	/* Import configuration flags related to flow creation */
656 	flags = iface->info.conf & NG_NETFLOW_FLOW_FLAGS;
657 
658 	NGI_GET_M(item, m);
659 	m_old = m;
660 
661 	/* Increase counters. */
662 	iface->info.ifinfo_packets++;
663 
664 	/*
665 	 * Depending on interface data link type and packet contents
666 	 * we pullup enough data, so that ng_netflow_flow_add() does not
667 	 * need to know about mbuf at all. We keep current length of data
668 	 * needed to be contiguous in pullup_len. mtod() is done at the
669 	 * very end one more time, since m can had changed after pulluping.
670 	 *
671 	 * In case of unrecognized data we don't return error, but just
672 	 * pass data to downstream hook, if it is available.
673 	 */
674 
675 #define	M_CHECK(length)	do {					\
676 	pullup_len += length;					\
677 	if (((m)->m_pkthdr.len < (pullup_len)) ||		\
678 	   ((pullup_len) > MHLEN)) {				\
679 		error = EINVAL;					\
680 		goto bypass;					\
681 	} 							\
682 	if ((m)->m_len < (pullup_len) &&			\
683 	   (((m) = m_pullup((m),(pullup_len))) == NULL)) {	\
684 		error = ENOBUFS;				\
685 		goto done;					\
686 	}							\
687 } while (0)
688 
689 	switch (iface->info.ifinfo_dlt) {
690 	case DLT_EN10MB:	/* Ethernet */
691 	    {
692 		struct ether_header *eh;
693 		uint16_t etype;
694 
695 		M_CHECK(sizeof(struct ether_header));
696 		eh = mtod(m, struct ether_header *);
697 
698 		/* Make sure this is IP frame. */
699 		etype = ntohs(eh->ether_type);
700 		switch (etype) {
701 		case ETHERTYPE_IP:
702 			M_CHECK(sizeof(struct ip));
703 			eh = mtod(m, struct ether_header *);
704 			ip = (struct ip *)(eh + 1);
705 			l3_off = sizeof(struct ether_header);
706 			break;
707 #ifdef INET6
708 		case ETHERTYPE_IPV6:
709 			/*
710 			 * m_pullup() called by M_CHECK() pullups
711 			 * kern.ipc.max_protohdr (default 60 bytes)
712 			 * which is enough.
713 			 */
714 			M_CHECK(sizeof(struct ip6_hdr));
715 			eh = mtod(m, struct ether_header *);
716 			ip6 = (struct ip6_hdr *)(eh + 1);
717 			l3_off = sizeof(struct ether_header);
718 			break;
719 #endif
720 		case ETHERTYPE_VLAN:
721 		    {
722 			struct ether_vlan_header *evh;
723 
724 			M_CHECK(sizeof(struct ether_vlan_header) -
725 			    sizeof(struct ether_header));
726 			evh = mtod(m, struct ether_vlan_header *);
727 			etype = ntohs(evh->evl_proto);
728 			l3_off = sizeof(struct ether_vlan_header);
729 
730 			if (etype == ETHERTYPE_IP) {
731 				M_CHECK(sizeof(struct ip));
732 				ip = (struct ip *)(evh + 1);
733 				break;
734 #ifdef INET6
735 			} else if (etype == ETHERTYPE_IPV6) {
736 				M_CHECK(sizeof(struct ip6_hdr));
737 				ip6 = (struct ip6_hdr *)(evh + 1);
738 				break;
739 #endif
740 			}
741 		    }
742 		default:
743 			goto bypass;	/* pass this frame */
744 		}
745 		break;
746 	    }
747 	case DLT_RAW:		/* IP packets */
748 		M_CHECK(sizeof(struct ip));
749 		ip = mtod(m, struct ip *);
750 		/* l3_off is already zero */
751 #ifdef INET6
752 		/*
753 		 * If INET6 is not defined IPv6 packets
754 		 * will be discarded in ng_netflow_flow_add().
755 		 */
756 		if (ip->ip_v == IP6VERSION) {
757 			ip = NULL;
758 			M_CHECK(sizeof(struct ip6_hdr) - sizeof(struct ip));
759 			ip6 = mtod(m, struct ip6_hdr *);
760 		}
761 #endif
762 		break;
763 	default:
764 		goto bypass;
765 		break;
766 	}
767 
768 	off = pullup_len;
769 
770 	if ((ip != NULL) && ((ip->ip_off & htons(IP_OFFMASK)) == 0)) {
771 		if ((ip->ip_v != IPVERSION) ||
772 		    ((ip->ip_hl << 2) < sizeof(struct ip)))
773 			goto bypass;
774 		/*
775 		 * In case of IPv4 header with options, we haven't pulled
776 		 * up enough, yet.
777 		 */
778 		M_CHECK((ip->ip_hl << 2) - sizeof(struct ip));
779 
780 		/* Save upper layer offset and proto */
781 		off = pullup_len;
782 		upper_proto = ip->ip_p;
783 
784 		/*
785 		 * XXX: in case of wrong upper layer header we will
786 		 * forward this packet but skip this record in netflow.
787 		 */
788 		switch (ip->ip_p) {
789 		case IPPROTO_TCP:
790 			M_CHECK(sizeof(struct tcphdr));
791 			break;
792 		case IPPROTO_UDP:
793 			M_CHECK(sizeof(struct udphdr));
794 			break;
795 		case IPPROTO_SCTP:
796 			M_CHECK(sizeof(struct sctphdr));
797 			break;
798 		}
799 	} else if (ip != NULL) {
800 		/*
801 		 * Nothing to save except upper layer proto,
802 		 * since this is a packet fragment.
803 		 */
804 		flags |= NG_NETFLOW_IS_FRAG;
805 		upper_proto = ip->ip_p;
806 		if ((ip->ip_v != IPVERSION) ||
807 		    ((ip->ip_hl << 2) < sizeof(struct ip)))
808 			goto bypass;
809 #ifdef INET6
810 	} else if (ip6 != NULL) {
811 		int cur = ip6->ip6_nxt, hdr_off = 0;
812 		struct ip6_ext *ip6e;
813 		struct ip6_frag *ip6f;
814 
815 		if (priv->export9 == NULL)
816 			goto bypass;
817 
818 		/* Save upper layer info. */
819 		off = pullup_len;
820 		upper_proto = cur;
821 
822 		if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION)
823 			goto bypass;
824 
825 		/*
826 		 * Loop thru IPv6 extended headers to get upper
827 		 * layer header / frag.
828 		 */
829 		for (;;) {
830 			switch (cur) {
831 			/*
832 			 * Same as in IPv4, we can forward a 'bad'
833 			 * packet without accounting.
834 			 */
835 			case IPPROTO_TCP:
836 				M_CHECK(sizeof(struct tcphdr));
837 				goto loopend;
838 			case IPPROTO_UDP:
839 				M_CHECK(sizeof(struct udphdr));
840 				goto loopend;
841 			case IPPROTO_SCTP:
842 				M_CHECK(sizeof(struct sctphdr));
843 				goto loopend;
844 
845 			/* Loop until 'real' upper layer headers */
846 			case IPPROTO_HOPOPTS:
847 			case IPPROTO_ROUTING:
848 			case IPPROTO_DSTOPTS:
849 				M_CHECK(sizeof(struct ip6_ext));
850 				ip6e = (struct ip6_ext *)(mtod(m, caddr_t) +
851 				    off);
852 				upper_proto = ip6e->ip6e_nxt;
853 				hdr_off = (ip6e->ip6e_len + 1) << 3;
854 				break;
855 
856 			/* RFC4302, can be before DSTOPTS */
857 			case IPPROTO_AH:
858 				M_CHECK(sizeof(struct ip6_ext));
859 				ip6e = (struct ip6_ext *)(mtod(m, caddr_t) +
860 				    off);
861 				upper_proto = ip6e->ip6e_nxt;
862 				hdr_off = (ip6e->ip6e_len + 2) << 2;
863 				break;
864 
865 			case IPPROTO_FRAGMENT:
866 				M_CHECK(sizeof(struct ip6_frag));
867 				ip6f = (struct ip6_frag *)(mtod(m, caddr_t) +
868 				    off);
869 				upper_proto = ip6f->ip6f_nxt;
870 				hdr_off = sizeof(struct ip6_frag);
871 				off += hdr_off;
872 				flags |= NG_NETFLOW_IS_FRAG;
873 				goto loopend;
874 
875 #if 0
876 			case IPPROTO_NONE:
877 				goto loopend;
878 #endif
879 			/*
880 			 * Any unknown header (new extension or IPv6/IPv4
881 			 * header for tunnels) ends loop.
882 			 */
883 			default:
884 				goto loopend;
885 			}
886 
887 			off += hdr_off;
888 			cur = upper_proto;
889 		}
890 #endif
891 	}
892 #undef	M_CHECK
893 
894 #ifdef INET6
895 loopend:
896 #endif
897 	/* Just in case of real reallocation in M_CHECK() / m_pullup() */
898 	if (m != m_old) {
899 		priv->nfinfo_realloc_mbuf++;
900 		/* Restore ip/ipv6 pointer */
901 		if (ip != NULL)
902 			ip = (struct ip *)(mtod(m, caddr_t) + l3_off);
903 		else if (ip6 != NULL)
904 			ip6 = (struct ip6_hdr *)(mtod(m, caddr_t) + l3_off);
905  	}
906 
907 	upper_ptr = (caddr_t)(mtod(m, caddr_t) + off);
908 
909 	/* Determine packet input interface. Prefer configured. */
910 	src_if_index = 0;
911 	if (hook == iface->out || iface->info.ifinfo_index == 0) {
912 		if (m->m_pkthdr.rcvif != NULL)
913 			src_if_index = m->m_pkthdr.rcvif->if_index;
914 	} else
915 		src_if_index = iface->info.ifinfo_index;
916 
917 	/* Check packet FIB */
918 	fib = M_GETFIB(m);
919 	if (fib >= priv->maxfibs) {
920 		CTR2(KTR_NET, "ng_netflow_rcvdata(): packet fib %d is out of "
921 		    "range of available fibs: 0 .. %d",
922 		    fib, priv->maxfibs);
923 		goto bypass;
924 	}
925 
926 	if ((fe = priv_to_fib(priv, fib)) == NULL) {
927 		/* Setup new FIB */
928 		if (ng_netflow_fib_init(priv, fib) != 0) {
929 			/* malloc() failed */
930 			goto bypass;
931 		}
932 
933 		fe = priv_to_fib(priv, fib);
934 	}
935 
936 	if (ip != NULL)
937 		error = ng_netflow_flow_add(priv, fe, ip, upper_ptr,
938 		    upper_proto, flags, src_if_index);
939 #ifdef INET6
940 	else if (ip6 != NULL)
941 		error = ng_netflow_flow6_add(priv, fe, ip6, upper_ptr,
942 		    upper_proto, flags, src_if_index);
943 #endif
944 	else
945 		goto bypass;
946 
947 	acct = 1;
948 bypass:
949 	if (out != NULL) {
950 		if (acct == 0) {
951 			/* Accounting failure */
952 			if (ip != NULL) {
953 				counter_u64_add(priv->nfinfo_spackets, 1);
954 				counter_u64_add(priv->nfinfo_sbytes,
955 				    m->m_pkthdr.len);
956 			} else if (ip6 != NULL) {
957 				counter_u64_add(priv->nfinfo_spackets6, 1);
958 				counter_u64_add(priv->nfinfo_sbytes6,
959 				    m->m_pkthdr.len);
960 			}
961 		}
962 
963 		/* XXX: error gets overwritten here */
964 		NG_FWD_NEW_DATA(error, item, out, m);
965 		return (error);
966 	}
967 done:
968 	if (item)
969 		NG_FREE_ITEM(item);
970 	if (m)
971 		NG_FREE_M(m);
972 
973 	return (error);
974 }
975 
976 /* We will be shut down in a moment */
977 static int
978 ng_netflow_close(node_p node)
979 {
980 	const priv_p priv = NG_NODE_PRIVATE(node);
981 
982 	callout_drain(&priv->exp_callout);
983 	ng_netflow_cache_flush(priv);
984 
985 	return (0);
986 }
987 
988 /* Do local shutdown processing. */
989 static int
990 ng_netflow_rmnode(node_p node)
991 {
992 	const priv_p priv = NG_NODE_PRIVATE(node);
993 
994 	NG_NODE_SET_PRIVATE(node, NULL);
995 	NG_NODE_UNREF(priv->node);
996 
997 	free(priv->fib_data, M_NETGRAPH);
998 	free(priv, M_NETGRAPH);
999 
1000 	return (0);
1001 }
1002 
1003 /* Hook disconnection. */
1004 static int
1005 ng_netflow_disconnect(hook_p hook)
1006 {
1007 	node_p node = NG_HOOK_NODE(hook);
1008 	priv_p priv = NG_NODE_PRIVATE(node);
1009 	iface_p iface = NG_HOOK_PRIVATE(hook);
1010 
1011 	if (iface != NULL) {
1012 		if (iface->hook == hook)
1013 			iface->hook = NULL;
1014 		if (iface->out == hook)
1015 			iface->out = NULL;
1016 	}
1017 
1018 	/* if export hook disconnected stop running expire(). */
1019 	if (hook == priv->export) {
1020 		if (priv->export9 == NULL)
1021 			callout_drain(&priv->exp_callout);
1022 		priv->export = NULL;
1023 	}
1024 
1025 	if (hook == priv->export9) {
1026 		if (priv->export == NULL)
1027 			callout_drain(&priv->exp_callout);
1028 		priv->export9 = NULL;
1029 	}
1030 
1031 	/* Removal of the last link destroys the node. */
1032 	if (NG_NODE_NUMHOOKS(node) == 0)
1033 		ng_rmnode_self(node);
1034 
1035 	return (0);
1036 }
1037