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1 /*-
2  * Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org>
3  * Copyright (c) 2001-2003 Roman V. Palagin <romanp@unshadow.net>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $SourceForge: ng_netflow.c,v 1.30 2004/09/05 11:37:43 glebius Exp $
28  */
29
30 static const char rcs_id[] =
31     "@(#) $FreeBSD$";
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/limits.h>
37 #include <sys/mbuf.h>
38 #include <sys/socket.h>
39 #include <sys/syslog.h>
40 #include <sys/ctype.h>
41
42 #include <net/if.h>
43 #include <net/ethernet.h>
44 #include <net/if_arp.h>
45 #include <net/if_var.h>
46 #include <net/if_vlan_var.h>
47 #include <net/bpf.h>
48 #include <netinet/in.h>
49 #include <netinet/in_systm.h>
50 #include <netinet/ip.h>
51 #include <netinet/tcp.h>
52 #include <netinet/udp.h>
53
54 #include <netgraph/ng_message.h>
55 #include <netgraph/ng_parse.h>
56 #include <netgraph/netgraph.h>
57 #include <netgraph/netflow/netflow.h>
58 #include <netgraph/netflow/ng_netflow.h>
59
60 /* Netgraph methods */
61 static ng_constructor_t ng_netflow_constructor;
62 static ng_rcvmsg_t      ng_netflow_rcvmsg;
63 static ng_close_t       ng_netflow_close;
64 static ng_shutdown_t    ng_netflow_rmnode;
65 static ng_newhook_t     ng_netflow_newhook;
66 static ng_rcvdata_t     ng_netflow_rcvdata;
67 static ng_disconnect_t  ng_netflow_disconnect;
68
69 /* Parse type for struct ng_netflow_info */
70 static const struct ng_parse_struct_field ng_netflow_info_type_fields[]
71         = NG_NETFLOW_INFO_TYPE;
72 static const struct ng_parse_type ng_netflow_info_type = {
73         &ng_parse_struct_type,
74         &ng_netflow_info_type_fields
75 };
76
77 /*  Parse type for struct ng_netflow_ifinfo */
78 static const struct ng_parse_struct_field ng_netflow_ifinfo_type_fields[]
79         = NG_NETFLOW_IFINFO_TYPE;
80 static const struct ng_parse_type ng_netflow_ifinfo_type = {
81         &ng_parse_struct_type,
82         &ng_netflow_ifinfo_type_fields
83 };
84
85 /* Parse type for struct ng_netflow_setdlt */
86 static const struct ng_parse_struct_field ng_netflow_setdlt_type_fields[]
87         = NG_NETFLOW_SETDLT_TYPE;
88 static const struct ng_parse_type ng_netflow_setdlt_type = {
89         &ng_parse_struct_type,
90         &ng_netflow_setdlt_type_fields
91 };
92
93 /* Parse type for ng_netflow_setifindex */
94 static const struct ng_parse_struct_field ng_netflow_setifindex_type_fields[]
95         = NG_NETFLOW_SETIFINDEX_TYPE;
96 static const struct ng_parse_type ng_netflow_setifindex_type = {
97         &ng_parse_struct_type,
98         &ng_netflow_setifindex_type_fields
99 };
100
101 /* Parse type for ng_netflow_settimeouts */
102 static const struct ng_parse_struct_field ng_netflow_settimeouts_type_fields[]
103         = NG_NETFLOW_SETTIMEOUTS_TYPE;
104 static const struct ng_parse_type ng_netflow_settimeouts_type = {
105         &ng_parse_struct_type,
106         &ng_netflow_settimeouts_type_fields
107 };
108
109 /* Parse type for ng_netflow_setconfig */
110 static const struct ng_parse_struct_field ng_netflow_setconfig_type_fields[]
111         = NG_NETFLOW_SETCONFIG_TYPE;
112 static const struct ng_parse_type ng_netflow_setconfig_type = {
113         &ng_parse_struct_type,
114         &ng_netflow_setconfig_type_fields
115 };
116
117 /* List of commands and how to convert arguments to/from ASCII */
118 static const struct ng_cmdlist ng_netflow_cmds[] = {
119        {
120          NGM_NETFLOW_COOKIE,
121          NGM_NETFLOW_INFO,
122          "info",
123          NULL,
124          &ng_netflow_info_type
125        },
126        {
127         NGM_NETFLOW_COOKIE,
128         NGM_NETFLOW_IFINFO,
129         "ifinfo",
130         &ng_parse_uint16_type,
131         &ng_netflow_ifinfo_type
132        },
133        {
134         NGM_NETFLOW_COOKIE,
135         NGM_NETFLOW_SETDLT,
136         "setdlt",
137         &ng_netflow_setdlt_type,
138         NULL
139        },
140        {
141         NGM_NETFLOW_COOKIE,
142         NGM_NETFLOW_SETIFINDEX,
143         "setifindex",
144         &ng_netflow_setifindex_type,
145         NULL
146        },
147        {
148         NGM_NETFLOW_COOKIE,
149         NGM_NETFLOW_SETTIMEOUTS,
150         "settimeouts",
151         &ng_netflow_settimeouts_type,
152         NULL
153        },
154        {
155         NGM_NETFLOW_COOKIE,
156         NGM_NETFLOW_SETCONFIG,
157         "setconfig",
158         &ng_netflow_setconfig_type,
159         NULL
160        },
161        { 0 }
162 };
163
164
165 /* Netgraph node type descriptor */
166 static struct ng_type ng_netflow_typestruct = {
167         .version =      NG_ABI_VERSION,
168         .name =         NG_NETFLOW_NODE_TYPE,
169         .constructor =  ng_netflow_constructor,
170         .rcvmsg =       ng_netflow_rcvmsg,
171         .close =        ng_netflow_close,
172         .shutdown =     ng_netflow_rmnode,
173         .newhook =      ng_netflow_newhook,
174         .rcvdata =      ng_netflow_rcvdata,
175         .disconnect =   ng_netflow_disconnect,
176         .cmdlist =      ng_netflow_cmds,
177 };
178 NETGRAPH_INIT(netflow, &ng_netflow_typestruct);
179
180 /* Called at node creation */
181 static int
182 ng_netflow_constructor(node_p node)
183 {
184         priv_p priv;
185         int error = 0, i;
186
187         /* Initialize private data */
188         priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT);
189         if (priv == NULL)
190                 return (ENOMEM);
191         bzero(priv, sizeof(*priv));
192
193         /* Make node and its data point at each other */
194         NG_NODE_SET_PRIVATE(node, priv);
195         priv->node = node;
196
197         /* Initialize timeouts to default values */
198         priv->info.nfinfo_inact_t = INACTIVE_TIMEOUT;
199         priv->info.nfinfo_act_t = ACTIVE_TIMEOUT;
200
201         /* Set default config */
202         for (i = 0; i < NG_NETFLOW_MAXIFACES; i++)
203                 priv->ifaces[i].info.conf = NG_NETFLOW_CONF_INGRESS;
204
205         /* Initialize callout handle */
206         callout_init(&priv->exp_callout, CALLOUT_MPSAFE);
207
208         /* Allocate memory and set up flow cache */
209         if ((error = ng_netflow_cache_init(priv)))
210                 return (error);
211
212         return (0);
213 }
214
215 /*
216  * ng_netflow supports two hooks: data and export.
217  * Incoming traffic is expected on data, and expired
218  * netflow datagrams are sent to export.
219  */
220 static int
221 ng_netflow_newhook(node_p node, hook_p hook, const char *name)
222 {
223         const priv_p priv = NG_NODE_PRIVATE(node);
224
225         if (strncmp(name, NG_NETFLOW_HOOK_DATA, /* an iface hook? */
226             strlen(NG_NETFLOW_HOOK_DATA)) == 0) {
227                 iface_p iface;
228                 int ifnum = -1;
229                 const char *cp;
230                 char *eptr;
231
232                 cp = name + strlen(NG_NETFLOW_HOOK_DATA);
233                 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
234                         return (EINVAL);
235
236                 ifnum = (int)strtoul(cp, &eptr, 10);
237                 if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
238                         return (EINVAL);
239
240                 /* See if hook is already connected */
241                 if (priv->ifaces[ifnum].hook != NULL)
242                         return (EISCONN);
243
244                 iface = &priv->ifaces[ifnum];
245
246                 /* Link private info and hook together */
247                 NG_HOOK_SET_PRIVATE(hook, iface);
248                 iface->hook = hook;
249
250                 /*
251                  * In most cases traffic accounting is done on an
252                  * Ethernet interface, so default data link type
253                  * will be DLT_EN10MB.
254                  */
255                 iface->info.ifinfo_dlt = DLT_EN10MB;
256
257         } else if (strncmp(name, NG_NETFLOW_HOOK_OUT,
258             strlen(NG_NETFLOW_HOOK_OUT)) == 0) {
259                 iface_p iface;
260                 int ifnum = -1;
261                 const char *cp;
262                 char *eptr;
263
264                 cp = name + strlen(NG_NETFLOW_HOOK_OUT);
265                 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
266                         return (EINVAL);
267
268                 ifnum = (int)strtoul(cp, &eptr, 10);
269                 if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
270                         return (EINVAL);
271
272                 /* See if hook is already connected */
273                 if (priv->ifaces[ifnum].out != NULL)
274                         return (EISCONN);
275
276                 iface = &priv->ifaces[ifnum];
277
278                 /* Link private info and hook together */
279                 NG_HOOK_SET_PRIVATE(hook, iface);
280                 iface->out = hook;
281
282         } else if (strcmp(name, NG_NETFLOW_HOOK_EXPORT) == 0) {
283
284                 if (priv->export != NULL)
285                         return (EISCONN);
286
287                 priv->export = hook;
288
289 #if 0   /* TODO: profile & test first */
290                 /*
291                  * We send export dgrams in interrupt handlers and in
292                  * callout threads. We'd better queue data for later
293                  * netgraph ISR processing.
294                  */
295                 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook));
296 #endif
297
298                 /* Exporter is ready. Let's schedule expiry. */
299                 callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire,
300                     (void *)priv);
301         } else
302                 return (EINVAL);
303
304         return (0);
305 }
306
307 /* Get a netgraph control message. */
308 static int
309 ng_netflow_rcvmsg (node_p node, item_p item, hook_p lasthook)
310 {
311         const priv_p priv = NG_NODE_PRIVATE(node);
312         struct ng_mesg *resp = NULL;
313         int error = 0;
314         struct ng_mesg *msg;
315
316         NGI_GET_MSG(item, msg);
317
318         /* Deal with message according to cookie and command */
319         switch (msg->header.typecookie) {
320         case NGM_NETFLOW_COOKIE:
321                 switch (msg->header.cmd) {
322                 case NGM_NETFLOW_INFO:
323                 {
324                         struct ng_netflow_info *i;
325
326                         NG_MKRESPONSE(resp, msg, sizeof(struct ng_netflow_info),
327                             M_NOWAIT);
328                         i = (struct ng_netflow_info *)resp->data;
329                         ng_netflow_copyinfo(priv, i);
330
331                         break;
332                 }
333                 case NGM_NETFLOW_IFINFO:
334                 {
335                         struct ng_netflow_ifinfo *i;
336                         const uint16_t *index;
337
338                         if (msg->header.arglen != sizeof(uint16_t))
339                                  ERROUT(EINVAL);
340
341                         index  = (uint16_t *)msg->data;
342                         if (*index >= NG_NETFLOW_MAXIFACES)
343                                 ERROUT(EINVAL);
344
345                         /* connected iface? */
346                         if (priv->ifaces[*index].hook == NULL)
347                                  ERROUT(EINVAL);
348
349                         NG_MKRESPONSE(resp, msg,
350                              sizeof(struct ng_netflow_ifinfo), M_NOWAIT);
351                         i = (struct ng_netflow_ifinfo *)resp->data;
352                         memcpy((void *)i, (void *)&priv->ifaces[*index].info,
353                             sizeof(priv->ifaces[*index].info));
354
355                         break;
356                 }
357                 case NGM_NETFLOW_SETDLT:
358                 {
359                         struct ng_netflow_setdlt *set;
360                         struct ng_netflow_iface *iface;
361
362                         if (msg->header.arglen != sizeof(struct ng_netflow_setdlt))
363                                 ERROUT(EINVAL);
364
365                         set = (struct ng_netflow_setdlt *)msg->data;
366                         if (set->iface >= NG_NETFLOW_MAXIFACES)
367                                 ERROUT(EINVAL);
368                         iface = &priv->ifaces[set->iface];
369
370                         /* connected iface? */
371                         if (iface->hook == NULL)
372                                 ERROUT(EINVAL);
373
374                         switch (set->dlt) {
375                         case    DLT_EN10MB:
376                                 iface->info.ifinfo_dlt = DLT_EN10MB;
377                                 break;
378                         case    DLT_RAW:
379                                 iface->info.ifinfo_dlt = DLT_RAW;
380                                 break;
381                         default:
382                                 ERROUT(EINVAL);
383                         }
384                         break;
385                 }
386                 case NGM_NETFLOW_SETIFINDEX:
387                 {
388                         struct ng_netflow_setifindex *set;
389                         struct ng_netflow_iface *iface;
390
391                         if (msg->header.arglen != sizeof(struct ng_netflow_setifindex))
392                                 ERROUT(EINVAL);
393
394                         set = (struct ng_netflow_setifindex *)msg->data;
395                         if (set->iface >= NG_NETFLOW_MAXIFACES)
396                                 ERROUT(EINVAL);
397                         iface = &priv->ifaces[set->iface];
398
399                         /* connected iface? */
400                         if (iface->hook == NULL)
401                                 ERROUT(EINVAL);
402
403                         iface->info.ifinfo_index = set->index;
404
405                         break;
406                 }
407                 case NGM_NETFLOW_SETTIMEOUTS:
408                 {
409                         struct ng_netflow_settimeouts *set;
410
411                         if (msg->header.arglen != sizeof(struct ng_netflow_settimeouts))
412                                 ERROUT(EINVAL);
413
414                         set = (struct ng_netflow_settimeouts *)msg->data;
415
416                         priv->info.nfinfo_inact_t = set->inactive_timeout;
417                         priv->info.nfinfo_act_t = set->active_timeout;
418
419                         break;
420                 }
421                 case NGM_NETFLOW_SETCONFIG:
422                 {
423                         struct ng_netflow_setconfig *set;
424
425                         if (msg->header.arglen != sizeof(struct ng_netflow_setconfig))
426                                 ERROUT(EINVAL);
427
428                         set = (struct ng_netflow_setconfig *)msg->data;
429
430                         if (set->iface >= NG_NETFLOW_MAXIFACES)
431                                 ERROUT(EINVAL);
432                         
433                         priv->ifaces[set->iface].info.conf = set->conf;
434         
435                         break;
436                 }
437                 case NGM_NETFLOW_SHOW:
438                 {
439                         uint32_t *last;
440
441                         if (msg->header.arglen != sizeof(uint32_t))
442                                 ERROUT(EINVAL);
443
444                         last = (uint32_t *)msg->data;
445
446                         NG_MKRESPONSE(resp, msg, NGRESP_SIZE, M_NOWAIT);
447
448                         if (!resp)
449                                 ERROUT(ENOMEM);
450
451                         error = ng_netflow_flow_show(priv, *last, resp);
452
453                         break;
454                 }
455                 default:
456                         ERROUT(EINVAL);         /* unknown command */
457                         break;
458                 }
459                 break;
460         default:
461                 ERROUT(EINVAL);         /* incorrect cookie */
462                 break;
463         }
464
465         /*
466          * Take care of synchronous response, if any.
467          * Free memory and return.
468          */
469 done:
470         NG_RESPOND_MSG(error, node, item, resp);
471         NG_FREE_MSG(msg);
472
473         return (error);
474 }
475
476 /* Receive data on hook. */
477 static int
478 ng_netflow_rcvdata (hook_p hook, item_p item)
479 {
480         const node_p node = NG_HOOK_NODE(hook);
481         const priv_p priv = NG_NODE_PRIVATE(node);
482         const iface_p iface = NG_HOOK_PRIVATE(hook);
483         hook_p out;
484         struct mbuf *m = NULL;
485         struct ip *ip;
486         struct m_tag *mtag;
487         int pullup_len = 0;
488         int error = 0, bypass = 0;
489         unsigned int src_if_index;
490
491         if (hook == priv->export) {
492                 /*
493                  * Data arrived on export hook.
494                  * This must not happen.
495                  */
496                 log(LOG_ERR, "ng_netflow: incoming data on export hook!\n");
497                 ERROUT(EINVAL);
498         };
499
500         if (hook == iface->hook) {
501                 if ((iface->info.conf & NG_NETFLOW_CONF_INGRESS) == 0)
502                         bypass = 1;
503                 out = iface->out;
504         } else if (hook == iface->out) {
505                 if ((iface->info.conf & NG_NETFLOW_CONF_EGRESS) == 0)
506                         bypass = 1;
507                 out = iface->hook;
508         } else 
509                 ERROUT(EINVAL);
510         
511         if ((!bypass) &&
512             (iface->info.conf & (NG_NETFLOW_CONF_ONCE | NG_NETFLOW_CONF_THISONCE))) {
513                 mtag = m_tag_locate(NGI_M(item), MTAG_NETFLOW,
514                     MTAG_NETFLOW_CALLED, NULL);
515                 while (mtag != NULL) {
516                         if ((iface->info.conf & NG_NETFLOW_CONF_ONCE) ||
517                             ((ng_ID_t *)(mtag + 1))[0] == NG_NODE_ID(node)) {
518                                 bypass = 1;
519                                 break;
520                         }
521                         mtag = m_tag_locate(NGI_M(item), MTAG_NETFLOW,
522                             MTAG_NETFLOW_CALLED, mtag);
523                 }
524         }
525         
526         if (bypass) {
527                 if (out == NULL)
528                         ERROUT(ENOTCONN);
529
530                 NG_FWD_ITEM_HOOK(error, item, out);
531                 return (error);
532         }
533         
534         if (iface->info.conf & (NG_NETFLOW_CONF_ONCE | NG_NETFLOW_CONF_THISONCE)) {
535                 mtag = m_tag_alloc(MTAG_NETFLOW, MTAG_NETFLOW_CALLED,
536                     sizeof(ng_ID_t), M_NOWAIT);
537                 if (mtag) {
538                         ((ng_ID_t *)(mtag + 1))[0] = NG_NODE_ID(node);
539                         m_tag_prepend(NGI_M(item), mtag);
540                 }
541         }
542
543         NGI_GET_M(item, m);
544
545         /* Increase counters. */
546         iface->info.ifinfo_packets++;
547
548         /*
549          * Depending on interface data link type and packet contents
550          * we pullup enough data, so that ng_netflow_flow_add() does not
551          * need to know about mbuf at all. We keep current length of data
552          * needed to be contiguous in pullup_len. mtod() is done at the
553          * very end one more time, since m can had changed after pulluping.
554          *
555          * In case of unrecognized data we don't return error, but just
556          * pass data to downstream hook, if it is available.
557          */
558
559 #define M_CHECK(length) do {                                    \
560         pullup_len += length;                                   \
561         if ((m)->m_pkthdr.len < (pullup_len)) {                 \
562                 error = EINVAL;                                 \
563                 goto bypass;                                    \
564         }                                                       \
565         if ((m)->m_len < (pullup_len) &&                        \
566            (((m) = m_pullup((m),(pullup_len))) == NULL)) {      \
567                 error = ENOBUFS;                                \
568                 goto done;                                      \
569         }                                                       \
570 } while (0)
571
572         switch (iface->info.ifinfo_dlt) {
573         case DLT_EN10MB:        /* Ethernet */
574             {
575                 struct ether_header *eh;
576                 uint16_t etype;
577
578                 M_CHECK(sizeof(struct ether_header));
579                 eh = mtod(m, struct ether_header *);
580
581                 /* Make sure this is IP frame. */
582                 etype = ntohs(eh->ether_type);
583                 switch (etype) {
584                 case ETHERTYPE_IP:
585                         M_CHECK(sizeof(struct ip));
586                         eh = mtod(m, struct ether_header *);
587                         ip = (struct ip *)(eh + 1);
588                         break;
589                 case ETHERTYPE_VLAN:
590                     {
591                         struct ether_vlan_header *evh;
592
593                         M_CHECK(sizeof(struct ether_vlan_header) -
594                             sizeof(struct ether_header));
595                         evh = mtod(m, struct ether_vlan_header *);
596                         if (ntohs(evh->evl_proto) == ETHERTYPE_IP) {
597                                 M_CHECK(sizeof(struct ip));
598                                 ip = (struct ip *)(evh + 1);
599                                 break;
600                         }
601                     }
602                 default:
603                         goto bypass;    /* pass this frame */
604                 }
605                 break;
606             }
607         case DLT_RAW:           /* IP packets */
608                 M_CHECK(sizeof(struct ip));
609                 ip = mtod(m, struct ip *);
610                 break;
611         default:
612                 goto bypass;
613                 break;
614         }
615
616         if ((ip->ip_off & htons(IP_OFFMASK)) == 0) {
617                 /*
618                  * In case of IP header with options, we haven't pulled
619                  * up enough, yet.
620                  */
621                 pullup_len += (ip->ip_hl << 2) - sizeof(struct ip);
622
623                 switch (ip->ip_p) {
624                 case IPPROTO_TCP:
625                         M_CHECK(sizeof(struct tcphdr));
626                         break;
627                 case IPPROTO_UDP:
628                         M_CHECK(sizeof(struct udphdr));
629                         break;
630                 }
631         }
632
633         switch (iface->info.ifinfo_dlt) {
634         case DLT_EN10MB:
635             {
636                 struct ether_header *eh;
637
638                 eh = mtod(m, struct ether_header *);
639                 switch (ntohs(eh->ether_type)) {
640                 case ETHERTYPE_IP:
641                         ip = (struct ip *)(eh + 1);
642                         break;
643                 case ETHERTYPE_VLAN:
644                     {
645                         struct ether_vlan_header *evh;
646
647                         evh = mtod(m, struct ether_vlan_header *);
648                         ip = (struct ip *)(evh + 1);
649                         break;
650                      }
651                 default:
652                         panic("ng_netflow entered deadcode");
653                 }
654                 break;
655              }
656         case DLT_RAW:
657                 ip = mtod(m, struct ip *);
658                 break;
659         default:
660                 panic("ng_netflow entered deadcode");
661         }
662
663 #undef  M_CHECK
664
665         /* Determine packet input interface. Prefer configured. */
666         src_if_index = 0;
667         if (hook == iface->out || iface->info.ifinfo_index == 0) {
668                 if (m->m_pkthdr.rcvif != NULL)
669                         src_if_index = m->m_pkthdr.rcvif->if_index;
670         } else
671                 src_if_index = iface->info.ifinfo_index;
672
673         error = ng_netflow_flow_add(priv, ip, src_if_index);
674
675 bypass:
676         if (out != NULL) {
677                 /* XXX: error gets overwritten here */
678                 NG_FWD_NEW_DATA(error, item, out, m);
679                 return (error);
680         }
681 done:
682         if (item)
683                 NG_FREE_ITEM(item);
684         if (m)
685                 NG_FREE_M(m);
686
687         return (error); 
688 }
689
690 /* We will be shut down in a moment */
691 static int
692 ng_netflow_close(node_p node)
693 {
694         const priv_p priv = NG_NODE_PRIVATE(node);
695
696         callout_drain(&priv->exp_callout);
697         ng_netflow_cache_flush(priv);
698
699         return (0);
700 }
701
702 /* Do local shutdown processing. */
703 static int
704 ng_netflow_rmnode(node_p node)
705 {
706         const priv_p priv = NG_NODE_PRIVATE(node);
707
708         NG_NODE_SET_PRIVATE(node, NULL);
709         NG_NODE_UNREF(priv->node);
710
711         free(priv, M_NETGRAPH);
712
713         return (0);
714 }
715
716 /* Hook disconnection. */
717 static int
718 ng_netflow_disconnect(hook_p hook)
719 {
720         node_p node = NG_HOOK_NODE(hook);
721         priv_p priv = NG_NODE_PRIVATE(node);
722         iface_p iface = NG_HOOK_PRIVATE(hook);
723
724         if (iface != NULL) {
725                 if (iface->hook == hook)
726                         iface->hook = NULL;
727                 if (iface->out == hook)
728                         iface->out = NULL;
729         }
730
731         /* if export hook disconnected stop running expire(). */
732         if (hook == priv->export) {
733                 callout_drain(&priv->exp_callout);
734                 priv->export = NULL;
735         }
736
737         /* Removal of the last link destroys the node. */
738         if (NG_NODE_NUMHOOKS(node) == 0)
739                 ng_rmnode_self(node);
740
741         return (0);
742 }