xref: /freebsd/sys/netgraph/netflow/netflow_v9.c (revision 4ec234c813eed05c166859bba82c882e40826eb9)
1 /*-
2  * Copyright (c) 2010 Alexander V. Chernikov <melifaro@ipfw.ru>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * 	$FreeBSD$
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_inet6.h"
33 #include "opt_route.h"
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/counter.h>
37 #include <sys/kernel.h>
38 #include <sys/limits.h>
39 #include <sys/mbuf.h>
40 #include <sys/syslog.h>
41 #include <sys/socket.h>
42 
43 #include <net/if.h>
44 #include <net/route.h>
45 #include <net/ethernet.h>
46 #include <netinet/in.h>
47 #include <netinet/in_systm.h>
48 #include <netinet/ip.h>
49 #include <netinet/ip6.h>
50 #include <netinet/tcp.h>
51 #include <netinet/udp.h>
52 
53 #include <netgraph/ng_message.h>
54 #include <netgraph/netgraph.h>
55 
56 #include <netgraph/netflow/netflow.h>
57 #include <netgraph/netflow/ng_netflow.h>
58 #include <netgraph/netflow/netflow_v9.h>
59 
60 MALLOC_DECLARE(M_NETFLOW_GENERAL);
61 MALLOC_DEFINE(M_NETFLOW_GENERAL, "netflow_general", "plog, V9 templates data");
62 
63 /*
64  * Base V9 templates for L4+ IPv4/IPv6 protocols
65  */
66 struct netflow_v9_template _netflow_v9_record_ipv4_tcp[] =
67 {
68 	{ NETFLOW_V9_FIELD_IPV4_SRC_ADDR, 4},
69 	{ NETFLOW_V9_FIELD_IPV4_DST_ADDR, 4},
70 	{ NETFLOW_V9_FIELD_IPV4_NEXT_HOP, 4},
71 	{ NETFLOW_V9_FIELD_INPUT_SNMP, 2},
72 	{ NETFLOW_V9_FIELD_OUTPUT_SNMP, 2},
73 	{ NETFLOW_V9_FIELD_IN_PKTS, sizeof(CNTR)},
74 	{ NETFLOW_V9_FIELD_IN_BYTES, sizeof(CNTR)},
75 	{ NETFLOW_V9_FIELD_OUT_PKTS, sizeof(CNTR)},
76 	{ NETFLOW_V9_FIELD_OUT_BYTES, sizeof(CNTR)},
77 	{ NETFLOW_V9_FIELD_FIRST_SWITCHED, 4},
78 	{ NETFLOW_V9_FIELD_LAST_SWITCHED, 4},
79 	{ NETFLOW_V9_FIELD_L4_SRC_PORT, 2},
80 	{ NETFLOW_V9_FIELD_L4_DST_PORT, 2},
81 	{ NETFLOW_V9_FIELD_TCP_FLAGS, 1},
82 	{ NETFLOW_V9_FIELD_PROTOCOL, 1},
83 	{ NETFLOW_V9_FIELD_TOS, 1},
84 	{ NETFLOW_V9_FIELD_SRC_AS, 4},
85 	{ NETFLOW_V9_FIELD_DST_AS, 4},
86 	{ NETFLOW_V9_FIELD_SRC_MASK, 1},
87 	{ NETFLOW_V9_FIELD_DST_MASK, 1},
88 	{0, 0}
89 };
90 
91 struct netflow_v9_template _netflow_v9_record_ipv6_tcp[] =
92 {
93 	{ NETFLOW_V9_FIELD_IPV6_SRC_ADDR, 16},
94 	{ NETFLOW_V9_FIELD_IPV6_DST_ADDR, 16},
95 	{ NETFLOW_V9_FIELD_IPV6_NEXT_HOP, 16},
96 	{ NETFLOW_V9_FIELD_INPUT_SNMP, 2},
97 	{ NETFLOW_V9_FIELD_OUTPUT_SNMP, 2},
98 	{ NETFLOW_V9_FIELD_IN_PKTS, sizeof(CNTR)},
99 	{ NETFLOW_V9_FIELD_IN_BYTES, sizeof(CNTR)},
100 	{ NETFLOW_V9_FIELD_OUT_PKTS, sizeof(CNTR)},
101 	{ NETFLOW_V9_FIELD_OUT_BYTES, sizeof(CNTR)},
102 	{ NETFLOW_V9_FIELD_FIRST_SWITCHED, 4},
103 	{ NETFLOW_V9_FIELD_LAST_SWITCHED, 4},
104 	{ NETFLOW_V9_FIELD_L4_SRC_PORT, 2},
105 	{ NETFLOW_V9_FIELD_L4_DST_PORT, 2},
106 	{ NETFLOW_V9_FIELD_TCP_FLAGS, 1},
107 	{ NETFLOW_V9_FIELD_PROTOCOL, 1},
108 	{ NETFLOW_V9_FIELD_TOS, 1},
109 	{ NETFLOW_V9_FIELD_SRC_AS, 4},
110 	{ NETFLOW_V9_FIELD_DST_AS, 4},
111 	{ NETFLOW_V9_FIELD_SRC_MASK, 1},
112 	{ NETFLOW_V9_FIELD_DST_MASK, 1},
113 	{0, 0}
114 };
115 
116 /*
117  * Pre-compiles flow exporter for all possible FlowSets
118  * so we can add flowset to packet via simple memcpy()
119  */
120 static void
121 generate_v9_templates(priv_p priv)
122 {
123 	uint16_t *p, *template_fields_cnt;
124 	int cnt;
125 
126 	int flowset_size = sizeof(struct netflow_v9_flowset_header) +
127 		_NETFLOW_V9_TEMPLATE_SIZE(_netflow_v9_record_ipv4_tcp) + /* netflow_v9_record_ipv4_tcp */
128 		_NETFLOW_V9_TEMPLATE_SIZE(_netflow_v9_record_ipv6_tcp); /* netflow_v9_record_ipv6_tcp */
129 
130 	priv->v9_flowsets[0] = malloc(flowset_size, M_NETFLOW_GENERAL, M_WAITOK | M_ZERO);
131 
132 	if (flowset_size % 4)
133 		flowset_size += 4 - (flowset_size % 4); /* Padding to 4-byte boundary */
134 
135 	priv->flowsets_count = 1;
136 	p = (uint16_t *)priv->v9_flowsets[0];
137 	*p++ = 0; /* Flowset ID, 0 is reserved for Template FlowSets  */
138 	*p++ = htons(flowset_size); /* Total FlowSet length */
139 
140 	/*
141 	 * Most common TCP/UDP IPv4 template, ID = 256
142 	 */
143 	*p++ = htons(NETFLOW_V9_MAX_RESERVED_FLOWSET + NETFLOW_V9_FLOW_V4_L4);
144 	template_fields_cnt = p++;
145 	for (cnt = 0; _netflow_v9_record_ipv4_tcp[cnt].field_id != 0; cnt++) {
146 		*p++ = htons(_netflow_v9_record_ipv4_tcp[cnt].field_id);
147 		*p++ = htons(_netflow_v9_record_ipv4_tcp[cnt].field_length);
148 	}
149 	*template_fields_cnt = htons(cnt);
150 
151 	/*
152 	 * TCP/UDP IPv6 template, ID = 257
153 	 */
154 	*p++ = htons(NETFLOW_V9_MAX_RESERVED_FLOWSET + NETFLOW_V9_FLOW_V6_L4);
155 	template_fields_cnt = p++;
156 	for (cnt = 0; _netflow_v9_record_ipv6_tcp[cnt].field_id != 0; cnt++) {
157 		*p++ = htons(_netflow_v9_record_ipv6_tcp[cnt].field_id);
158 		*p++ = htons(_netflow_v9_record_ipv6_tcp[cnt].field_length);
159 	}
160 	*template_fields_cnt = htons(cnt);
161 
162 	priv->flowset_records[0] = 2;
163 }
164 
165 /* Closes current data flowset */
166 static void inline
167 close_flowset(struct mbuf *m, struct netflow_v9_packet_opt *t)
168 {
169 	struct mbuf *m_old;
170 	uint32_t zero = 0;
171 	int offset = 0;
172 	uint16_t *flowset_length, len;
173 
174 	/* Hack to ensure we are not crossing mbuf boundary, length is uint16_t  */
175 	m_old = m_getptr(m, t->flow_header + offsetof(struct netflow_v9_flowset_header, length), &offset);
176 	flowset_length = (uint16_t *)(mtod(m_old, char *) + offset);
177 
178 	len = (uint16_t)(m_pktlen(m) - t->flow_header);
179 	/* Align on 4-byte boundary (RFC 3954, Clause 5.3) */
180 	if (len % 4) {
181 		if (m_append(m, 4 - (len % 4), (void *)&zero) != 1)
182 			panic("ng_netflow: m_append() failed!");
183 
184 		len += 4 - (len % 4);
185 	}
186 
187 	*flowset_length = htons(len);
188 }
189 
190 /*
191  * Non-static functions called from ng_netflow.c
192  */
193 
194 /* We have full datagram in fib data. Send it to export hook. */
195 int
196 export9_send(priv_p priv, fib_export_p fe, item_p item, struct netflow_v9_packet_opt *t, int flags)
197 {
198 	struct mbuf *m = NGI_M(item);
199 	struct netflow_v9_export_dgram *dgram = mtod(m,
200 					struct netflow_v9_export_dgram *);
201 	struct netflow_v9_header *header = &dgram->header;
202 	struct timespec ts;
203 	int error = 0;
204 
205 	if (t == NULL) {
206 		CTR0(KTR_NET, "export9_send(): V9 export packet without tag");
207 		NG_FREE_ITEM(item);
208 		return (0);
209 	}
210 
211 	/* Close flowset if not closed already */
212 	if (m_pktlen(m) != t->flow_header)
213 		close_flowset(m, t);
214 
215 	/* Fill export header. */
216 	header->count = t->count;
217 	header->sys_uptime = htonl(MILLIUPTIME(time_uptime));
218 	getnanotime(&ts);
219 	header->unix_secs  = htonl(ts.tv_sec);
220 	header->seq_num = htonl(atomic_fetchadd_32(&fe->flow9_seq, 1));
221 	header->count = htons(t->count);
222 	header->source_id = htonl(fe->domain_id);
223 
224 	if (priv->export9 != NULL)
225 		NG_FWD_ITEM_HOOK_FLAGS(error, item, priv->export9, flags);
226 	else
227 		NG_FREE_ITEM(item);
228 
229 	free(t, M_NETFLOW_GENERAL);
230 
231 	return (error);
232 }
233 
234 
235 
236 /* Add V9 record to dgram. */
237 int
238 export9_add(item_p item, struct netflow_v9_packet_opt *t, struct flow_entry *fle)
239 {
240 	size_t len = 0;
241 	struct netflow_v9_flowset_header fsh;
242 	struct netflow_v9_record_general rg;
243 	struct mbuf *m = NGI_M(item);
244 	uint16_t flow_type;
245 	struct flow_entry_data *fed;
246 #ifdef INET6
247 	struct flow6_entry_data *fed6;
248 #endif
249 	if (t == NULL) {
250 		CTR0(KTR_NET, "ng_netflow: V9 export packet without tag!");
251 		return (0);
252 	}
253 
254 	/* Prepare flow record */
255 	fed = (struct flow_entry_data *)&fle->f;
256 #ifdef INET6
257 	fed6 = (struct flow6_entry_data *)&fle->f;
258 #endif
259 	/* We can use flow_type field since fle6 offset is equal to fle */
260 	flow_type = fed->r.flow_type;
261 
262 	switch (flow_type) {
263 	case NETFLOW_V9_FLOW_V4_L4:
264 	{
265 		/* IPv4 TCP/UDP/[SCTP] */
266 		struct netflow_v9_record_ipv4_tcp *rec = &rg.rec.v4_tcp;
267 
268 		rec->src_addr = fed->r.r_src.s_addr;
269 		rec->dst_addr = fed->r.r_dst.s_addr;
270 		rec->next_hop = fed->next_hop.s_addr;
271 		rec->i_ifx    = htons(fed->fle_i_ifx);
272 		rec->o_ifx    = htons(fed->fle_o_ifx);
273 		rec->i_packets  = htonl(fed->packets);
274 		rec->i_octets   = htonl(fed->bytes);
275 		rec->o_packets  = htonl(0);
276 		rec->o_octets   = htonl(0);
277 		rec->first    = htonl(MILLIUPTIME(fed->first));
278 		rec->last     = htonl(MILLIUPTIME(fed->last));
279 		rec->s_port   = fed->r.r_sport;
280 		rec->d_port   = fed->r.r_dport;
281 		rec->flags    = fed->tcp_flags;
282 		rec->prot     = fed->r.r_ip_p;
283 		rec->tos      = fed->r.r_tos;
284 		rec->dst_mask = fed->dst_mask;
285 		rec->src_mask = fed->src_mask;
286 
287 		/* Not supported fields. */
288 		rec->src_as = rec->dst_as = 0;
289 
290 		len = sizeof(struct netflow_v9_record_ipv4_tcp);
291 		break;
292 	}
293 #ifdef INET6
294 	case NETFLOW_V9_FLOW_V6_L4:
295 	{
296 		/* IPv6 TCP/UDP/[SCTP] */
297 		struct netflow_v9_record_ipv6_tcp *rec = &rg.rec.v6_tcp;
298 
299 		rec->src_addr = fed6->r.src.r_src6;
300 		rec->dst_addr = fed6->r.dst.r_dst6;
301 		rec->next_hop = fed6->n.next_hop6;
302 		rec->i_ifx    = htons(fed6->fle_i_ifx);
303 		rec->o_ifx    = htons(fed6->fle_o_ifx);
304 		rec->i_packets  = htonl(fed6->packets);
305 		rec->i_octets   = htonl(fed6->bytes);
306 		rec->o_packets  = htonl(0);
307 		rec->o_octets   = htonl(0);
308 		rec->first    = htonl(MILLIUPTIME(fed6->first));
309 		rec->last     = htonl(MILLIUPTIME(fed6->last));
310 		rec->s_port   = fed6->r.r_sport;
311 		rec->d_port   = fed6->r.r_dport;
312 		rec->flags    = fed6->tcp_flags;
313 		rec->prot     = fed6->r.r_ip_p;
314 		rec->tos      = fed6->r.r_tos;
315 		rec->dst_mask = fed6->dst_mask;
316 		rec->src_mask = fed6->src_mask;
317 
318 		/* Not supported fields. */
319 		rec->src_as = rec->dst_as = 0;
320 
321 		len = sizeof(struct netflow_v9_record_ipv6_tcp);
322 		break;
323 	}
324 #endif
325 	default:
326 	{
327 		CTR1(KTR_NET, "export9_add(): Don't know what to do with %d flow type!", flow_type);
328 		return (0);
329 	}
330 	}
331 
332 	/* Check if new records has the same template */
333 	if (flow_type != t->flow_type) {
334 		/* close old flowset */
335 		if (t->flow_type != 0)
336 			close_flowset(m, t);
337 
338 		t->flow_type = flow_type;
339 		t->flow_header = m_pktlen(m);
340 
341 		/* Generate data flowset ID */
342 		fsh.id = htons(NETFLOW_V9_MAX_RESERVED_FLOWSET + flow_type);
343 		fsh.length = 0;
344 
345 		/* m_append should not fail since all data is already allocated */
346 		if (m_append(m, sizeof(fsh), (void *)&fsh) != 1)
347 			panic("ng_netflow: m_append() failed");
348 
349 	}
350 
351 	if (m_append(m, len, (void *)&rg.rec) != 1)
352 		panic("ng_netflow: m_append() failed");
353 
354 	t->count++;
355 
356 	if (m_pktlen(m) + sizeof(struct netflow_v9_record_general) + sizeof(struct netflow_v9_flowset_header) >= _NETFLOW_V9_MAX_SIZE(t->mtu))
357 		return (1); /* end of datagram */
358 	return (0);
359 }
360 
361 /*
362  * Detach export datagram from fib instance, if there is any.
363  * If there is no, allocate a new one.
364  */
365 item_p
366 get_export9_dgram(priv_p priv, fib_export_p fe, struct netflow_v9_packet_opt **tt)
367 {
368 	item_p	item = NULL;
369 	struct netflow_v9_packet_opt *t = NULL;
370 
371 	mtx_lock(&fe->export9_mtx);
372 	if (fe->exp.item9 != NULL) {
373 		item = fe->exp.item9;
374 		fe->exp.item9 = NULL;
375 		t = fe->exp.item9_opt;
376 		fe->exp.item9_opt = NULL;
377 	}
378 	mtx_unlock(&fe->export9_mtx);
379 
380 	if (item == NULL) {
381 		struct netflow_v9_export_dgram *dgram;
382 		struct mbuf *m;
383 		uint16_t mtu = priv->mtu;
384 
385 		/* Allocate entire packet at once, allowing easy m_append() calls */
386 		m = m_getm(NULL, mtu, M_NOWAIT, MT_DATA);
387 		if (m == NULL)
388 			return (NULL);
389 
390 		t = malloc(sizeof(struct netflow_v9_packet_opt), M_NETFLOW_GENERAL, M_NOWAIT | M_ZERO);
391 		if (t == NULL) {
392 			m_free(m);
393 			return (NULL);
394 		}
395 
396 		item = ng_package_data(m, NG_NOFLAGS);
397 		if (item == NULL) {
398 			free(t, M_NETFLOW_GENERAL);
399 			return (NULL);
400 		}
401 
402 		dgram = mtod(m, struct netflow_v9_export_dgram *);
403 		dgram->header.count = 0;
404 		dgram->header.version = htons(NETFLOW_V9);
405 		/* Set mbuf current data length */
406 		m->m_len = m->m_pkthdr.len = sizeof(struct netflow_v9_header);
407 
408 		t->count = 0;
409 		t->mtu = mtu;
410 		t->flow_header = m->m_len;
411 
412 		/*
413 		 * Check if we need to insert templates into packet
414 		 */
415 
416 		struct netflow_v9_flowset_header	*fl;
417 
418 		if ((time_uptime >= priv->templ_time + fe->templ_last_ts) ||
419 				(fe->sent_packets >= priv->templ_packets + fe->templ_last_pkt)) {
420 
421 			fe->templ_last_ts = time_uptime;
422 			fe->templ_last_pkt = fe->sent_packets;
423 
424 			fl = priv->v9_flowsets[0];
425 			m_append(m, ntohs(fl->length), (void *)fl);
426 			t->flow_header = m->m_len;
427 			t->count += priv->flowset_records[0];
428 		}
429 
430 	}
431 
432 	*tt = t;
433 	return (item);
434 }
435 
436 /*
437  * Re-attach incomplete datagram back to fib instance.
438  * If there is already another one, then send incomplete.
439  */
440 void
441 return_export9_dgram(priv_p priv, fib_export_p fe, item_p item, struct netflow_v9_packet_opt *t, int flags)
442 {
443 	/*
444 	 * It may happen on SMP, that some thread has already
445 	 * put its item there, in this case we bail out and
446 	 * send what we have to collector.
447 	 */
448 	mtx_lock(&fe->export9_mtx);
449 	if (fe->exp.item9 == NULL) {
450 		fe->exp.item9 = item;
451 		fe->exp.item9_opt = t;
452 		mtx_unlock(&fe->export9_mtx);
453 	} else {
454 		mtx_unlock(&fe->export9_mtx);
455 		export9_send(priv, fe, item, t, flags);
456 	}
457 }
458 
459 /* Allocate memory and set up flow cache */
460 void
461 ng_netflow_v9_cache_init(priv_p priv)
462 {
463 	generate_v9_templates(priv);
464 
465 	priv->templ_time = NETFLOW_V9_MAX_TIME_TEMPL;
466 	priv->templ_packets = NETFLOW_V9_MAX_PACKETS_TEMPL;
467 	priv->mtu = BASE_MTU;
468 }
469 
470 /* Free all flow cache memory. Called from ng_netflow_cache_flush() */
471 void
472 ng_netflow_v9_cache_flush(priv_p priv)
473 {
474 	int i;
475 
476 	/* Free flowsets*/
477 	for (i = 0; i < priv->flowsets_count; i++)
478 		free(priv->v9_flowsets[i], M_NETFLOW_GENERAL);
479 }
480 
481 /* Get a snapshot of NetFlow v9 settings */
482 void
483 ng_netflow_copyv9info(priv_p priv, struct ng_netflow_v9info *i)
484 {
485 
486 	i->templ_time = priv->templ_time;
487 	i->templ_packets = priv->templ_packets;
488 	i->mtu = priv->mtu;
489 }
490 
491