1 /*-
2 * Copyright (c) 2014 Gleb Smirnoff <glebius@FreeBSD.org>
3 * Copyright (c) 2008-2010, BitGravity Inc.
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 are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 *
12 * 2. Neither the name of the BitGravity Corporation nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND 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 COPYRIGHT OWNER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "opt_route.h"
30 #include "opt_mpath.h"
31 #include "opt_ddb.h"
32 #include "opt_inet.h"
33 #include "opt_inet6.h"
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: stable/10/sys/net/flowtable.c 281955 2015-04-24 23:26:44Z hiren $");
37
38 #include <sys/param.h>
39 #include <sys/types.h>
40 #include <sys/bitstring.h>
41 #include <sys/condvar.h>
42 #include <sys/callout.h>
43 #include <sys/hash.h>
44 #include <sys/kernel.h>
45 #include <sys/kthread.h>
46 #include <sys/limits.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/pcpu.h>
50 #include <sys/proc.h>
51 #include <sys/queue.h>
52 #include <sys/sbuf.h>
53 #include <sys/sched.h>
54 #include <sys/smp.h>
55 #include <sys/socket.h>
56 #include <sys/syslog.h>
57 #include <sys/sysctl.h>
58 #include <vm/uma.h>
59
60 #include <net/if.h>
61 #include <net/if_llatbl.h>
62 #include <net/if_var.h>
63 #include <net/route.h>
64 #include <net/flowtable.h>
65 #include <net/vnet.h>
66
67 #include <netinet/in.h>
68 #include <netinet/in_systm.h>
69 #include <netinet/in_var.h>
70 #include <netinet/if_ether.h>
71 #include <netinet/ip.h>
72 #ifdef INET6
73 #include <netinet/ip6.h>
74 #endif
75 #ifdef FLOWTABLE_HASH_ALL
76 #include <netinet/tcp.h>
77 #include <netinet/udp.h>
78 #include <netinet/sctp.h>
79 #endif
80
81 #include <ddb/ddb.h>
82
83 #ifdef FLOWTABLE_HASH_ALL
84 #define KEY_PORTS (sizeof(uint16_t) * 2)
85 #define KEY_ADDRS 2
86 #else
87 #define KEY_PORTS 0
88 #define KEY_ADDRS 1
89 #endif
90
91 #ifdef INET6
92 #define KEY_ADDR_LEN sizeof(struct in6_addr)
93 #else
94 #define KEY_ADDR_LEN sizeof(struct in_addr)
95 #endif
96
97 #define KEYLEN ((KEY_ADDR_LEN * KEY_ADDRS + KEY_PORTS) / sizeof(uint32_t))
98
99 struct flentry {
100 uint32_t f_hash; /* hash flowing forward */
101 uint32_t f_key[KEYLEN]; /* address(es and ports) */
102 uint32_t f_uptime; /* uptime at last access */
103 uint16_t f_fibnum; /* fib index */
104 #ifdef FLOWTABLE_HASH_ALL
105 uint8_t f_proto; /* protocol */
106 uint8_t f_flags; /* stale? */
107 #define FL_STALE 1
108 #endif
109 SLIST_ENTRY(flentry) f_next; /* pointer to collision entry */
110 struct rtentry *f_rt; /* rtentry for flow */
111 struct llentry *f_lle; /* llentry for flow */
112 };
113 #undef KEYLEN
114
115 SLIST_HEAD(flist, flentry);
116 /* Make sure we can use pcpu_zone_ptr for struct flist. */
117 CTASSERT(sizeof(struct flist) == sizeof(void *));
118
119 struct flowtable {
120 counter_u64_t *ft_stat;
121 int ft_size;
122 /*
123 * ft_table is a malloc(9)ed array of pointers. Pointers point to
124 * memory from UMA_ZONE_PCPU zone.
125 * ft_masks is per-cpu pointer itself. Each instance points
126 * to a malloc(9)ed bitset, that is private to corresponding CPU.
127 */
128 struct flist **ft_table;
129 bitstr_t **ft_masks;
130 bitstr_t *ft_tmpmask;
131 };
132
133 #define FLOWSTAT_ADD(ft, name, v) \
134 counter_u64_add((ft)->ft_stat[offsetof(struct flowtable_stat, name) / sizeof(uint64_t)], (v))
135 #define FLOWSTAT_INC(ft, name) FLOWSTAT_ADD(ft, name, 1)
136
137 static struct proc *flowcleanerproc;
138 static uint32_t flow_hashjitter;
139
140 static struct cv flowclean_f_cv;
141 static struct cv flowclean_c_cv;
142 static struct mtx flowclean_lock;
143 static uint32_t flowclean_cycles;
144
145 /*
146 * TODO:
147 * - add sysctls to resize && flush flow tables
148 * - Add per flowtable sysctls for statistics and configuring timeouts
149 * - add saturation counter to rtentry to support per-packet load-balancing
150 * add flag to indicate round-robin flow, add list lookup from head
151 for flows
152 * - add sysctl / device node / syscall to support exporting and importing
153 * of flows with flag to indicate that a flow was imported so should
154 * not be considered for auto-cleaning
155 * - support explicit connection state (currently only ad-hoc for DSR)
156 * - idetach() cleanup for options VIMAGE builds.
157 */
158 #ifdef INET
159 static VNET_DEFINE(struct flowtable, ip4_ft);
160 #define V_ip4_ft VNET(ip4_ft)
161 #endif
162 #ifdef INET6
163 static VNET_DEFINE(struct flowtable, ip6_ft);
164 #define V_ip6_ft VNET(ip6_ft)
165 #endif
166
167 static uma_zone_t flow_zone;
168
169 static VNET_DEFINE(int, flowtable_enable) = 1;
170 #define V_flowtable_enable VNET(flowtable_enable)
171
172 static SYSCTL_NODE(_net, OID_AUTO, flowtable, CTLFLAG_RD, NULL,
173 "flowtable");
174 SYSCTL_VNET_INT(_net_flowtable, OID_AUTO, enable, CTLFLAG_RW,
175 &VNET_NAME(flowtable_enable), 0, "enable flowtable caching.");
176 SYSCTL_UMA_MAX(_net_flowtable, OID_AUTO, maxflows, CTLFLAG_RW,
177 &flow_zone, "Maximum number of flows allowed");
178
179 static MALLOC_DEFINE(M_FTABLE, "flowtable", "flowtable hashes and bitstrings");
180
181 static struct flentry *
182 flowtable_lookup_common(struct flowtable *, uint32_t *, int, uint32_t);
183
184 #ifdef INET
185 static struct flentry *
flowtable_lookup_ipv4(struct mbuf * m,struct route * ro)186 flowtable_lookup_ipv4(struct mbuf *m, struct route *ro)
187 {
188 struct flentry *fle;
189 struct sockaddr_in *sin;
190 struct ip *ip;
191 uint32_t fibnum;
192 #ifdef FLOWTABLE_HASH_ALL
193 uint32_t key[3];
194 int iphlen;
195 uint16_t sport, dport;
196 uint8_t proto;
197 #endif
198
199 ip = mtod(m, struct ip *);
200
201 if (ip->ip_src.s_addr == ip->ip_dst.s_addr ||
202 (ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
203 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
204 return (NULL);
205
206 fibnum = M_GETFIB(m);
207
208 #ifdef FLOWTABLE_HASH_ALL
209 iphlen = ip->ip_hl << 2;
210 proto = ip->ip_p;
211
212 switch (proto) {
213 case IPPROTO_TCP: {
214 struct tcphdr *th;
215
216 th = (struct tcphdr *)((char *)ip + iphlen);
217 sport = th->th_sport;
218 dport = th->th_dport;
219 if (th->th_flags & (TH_RST|TH_FIN))
220 fibnum |= (FL_STALE << 24);
221 break;
222 }
223 case IPPROTO_UDP: {
224 struct udphdr *uh;
225
226 uh = (struct udphdr *)((char *)ip + iphlen);
227 sport = uh->uh_sport;
228 dport = uh->uh_dport;
229 break;
230 }
231 case IPPROTO_SCTP: {
232 struct sctphdr *sh;
233
234 sh = (struct sctphdr *)((char *)ip + iphlen);
235 sport = sh->src_port;
236 dport = sh->dest_port;
237 /* XXXGL: handle stale? */
238 break;
239 }
240 default:
241 sport = dport = 0;
242 break;
243 }
244
245 key[0] = ip->ip_dst.s_addr;
246 key[1] = ip->ip_src.s_addr;
247 key[2] = (dport << 16) | sport;
248 fibnum |= proto << 16;
249
250 fle = flowtable_lookup_common(&V_ip4_ft, key, 3 * sizeof(uint32_t),
251 fibnum);
252
253 #else /* !FLOWTABLE_HASH_ALL */
254
255 fle = flowtable_lookup_common(&V_ip4_ft, (uint32_t *)&ip->ip_dst,
256 sizeof(struct in_addr), fibnum);
257
258 #endif /* FLOWTABLE_HASH_ALL */
259
260 if (fle == NULL)
261 return (NULL);
262
263 sin = (struct sockaddr_in *)&ro->ro_dst;
264 sin->sin_family = AF_INET;
265 sin->sin_len = sizeof(*sin);
266 sin->sin_addr = ip->ip_dst;
267
268 return (fle);
269 }
270 #endif /* INET */
271
272 #ifdef INET6
273 /*
274 * PULLUP_TO(len, p, T) makes sure that len + sizeof(T) is contiguous,
275 * then it sets p to point at the offset "len" in the mbuf. WARNING: the
276 * pointer might become stale after other pullups (but we never use it
277 * this way).
278 */
279 #define PULLUP_TO(_len, p, T) \
280 do { \
281 int x = (_len) + sizeof(T); \
282 if ((m)->m_len < x) \
283 return (NULL); \
284 p = (mtod(m, char *) + (_len)); \
285 } while (0)
286
287 #define TCP(p) ((struct tcphdr *)(p))
288 #define SCTP(p) ((struct sctphdr *)(p))
289 #define UDP(p) ((struct udphdr *)(p))
290
291 static struct flentry *
flowtable_lookup_ipv6(struct mbuf * m,struct route * ro)292 flowtable_lookup_ipv6(struct mbuf *m, struct route *ro)
293 {
294 struct flentry *fle;
295 struct sockaddr_in6 *sin6;
296 struct ip6_hdr *ip6;
297 uint32_t fibnum;
298 #ifdef FLOWTABLE_HASH_ALL
299 uint32_t key[9];
300 void *ulp;
301 int hlen;
302 uint16_t sport, dport;
303 u_short offset;
304 uint8_t proto;
305 #else
306 uint32_t key[4];
307 #endif
308
309 ip6 = mtod(m, struct ip6_hdr *);
310 if (in6_localaddr(&ip6->ip6_dst))
311 return (NULL);
312
313 fibnum = M_GETFIB(m);
314
315 #ifdef FLOWTABLE_HASH_ALL
316 hlen = sizeof(struct ip6_hdr);
317 proto = ip6->ip6_nxt;
318 offset = sport = dport = 0;
319 ulp = NULL;
320 while (ulp == NULL) {
321 switch (proto) {
322 case IPPROTO_ICMPV6:
323 case IPPROTO_OSPFIGP:
324 case IPPROTO_PIM:
325 case IPPROTO_CARP:
326 case IPPROTO_ESP:
327 case IPPROTO_NONE:
328 ulp = ip6;
329 break;
330 case IPPROTO_TCP:
331 PULLUP_TO(hlen, ulp, struct tcphdr);
332 dport = TCP(ulp)->th_dport;
333 sport = TCP(ulp)->th_sport;
334 if (TCP(ulp)->th_flags & (TH_RST|TH_FIN))
335 fibnum |= (FL_STALE << 24);
336 break;
337 case IPPROTO_SCTP:
338 PULLUP_TO(hlen, ulp, struct sctphdr);
339 dport = SCTP(ulp)->src_port;
340 sport = SCTP(ulp)->dest_port;
341 /* XXXGL: handle stale? */
342 break;
343 case IPPROTO_UDP:
344 PULLUP_TO(hlen, ulp, struct udphdr);
345 dport = UDP(ulp)->uh_dport;
346 sport = UDP(ulp)->uh_sport;
347 break;
348 case IPPROTO_HOPOPTS: /* RFC 2460 */
349 PULLUP_TO(hlen, ulp, struct ip6_hbh);
350 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
351 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
352 ulp = NULL;
353 break;
354 case IPPROTO_ROUTING: /* RFC 2460 */
355 PULLUP_TO(hlen, ulp, struct ip6_rthdr);
356 hlen += (((struct ip6_rthdr *)ulp)->ip6r_len + 1) << 3;
357 proto = ((struct ip6_rthdr *)ulp)->ip6r_nxt;
358 ulp = NULL;
359 break;
360 case IPPROTO_FRAGMENT: /* RFC 2460 */
361 PULLUP_TO(hlen, ulp, struct ip6_frag);
362 hlen += sizeof (struct ip6_frag);
363 proto = ((struct ip6_frag *)ulp)->ip6f_nxt;
364 offset = ((struct ip6_frag *)ulp)->ip6f_offlg &
365 IP6F_OFF_MASK;
366 ulp = NULL;
367 break;
368 case IPPROTO_DSTOPTS: /* RFC 2460 */
369 PULLUP_TO(hlen, ulp, struct ip6_hbh);
370 hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
371 proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
372 ulp = NULL;
373 break;
374 case IPPROTO_AH: /* RFC 2402 */
375 PULLUP_TO(hlen, ulp, struct ip6_ext);
376 hlen += (((struct ip6_ext *)ulp)->ip6e_len + 2) << 2;
377 proto = ((struct ip6_ext *)ulp)->ip6e_nxt;
378 ulp = NULL;
379 break;
380 default:
381 PULLUP_TO(hlen, ulp, struct ip6_ext);
382 break;
383 }
384 }
385
386 bcopy(&ip6->ip6_dst, &key[0], sizeof(struct in6_addr));
387 bcopy(&ip6->ip6_src, &key[4], sizeof(struct in6_addr));
388 key[8] = (dport << 16) | sport;
389 fibnum |= proto << 16;
390
391 fle = flowtable_lookup_common(&V_ip6_ft, key, 9 * sizeof(uint32_t),
392 fibnum);
393 #else /* !FLOWTABLE_HASH_ALL */
394 bcopy(&ip6->ip6_dst, &key[0], sizeof(struct in6_addr));
395 fle = flowtable_lookup_common(&V_ip6_ft, key, sizeof(struct in6_addr),
396 fibnum);
397 #endif /* FLOWTABLE_HASH_ALL */
398
399 if (fle == NULL)
400 return (NULL);
401
402 sin6 = (struct sockaddr_in6 *)&ro->ro_dst;
403 sin6->sin6_family = AF_INET6;
404 sin6->sin6_len = sizeof(*sin6);
405 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(struct in6_addr));
406
407 return (fle);
408 }
409 #endif /* INET6 */
410
411 static bitstr_t *
flowtable_mask(struct flowtable * ft)412 flowtable_mask(struct flowtable *ft)
413 {
414
415 /*
416 * flowtable_free_stale() calls w/o critical section, but
417 * with sched_bind(). Since pointer is stable throughout
418 * ft lifetime, it is safe, otherwise...
419 *
420 * CRITICAL_ASSERT(curthread);
421 */
422
423 return (*(bitstr_t **)zpcpu_get(ft->ft_masks));
424 }
425
426 static struct flist *
flowtable_list(struct flowtable * ft,uint32_t hash)427 flowtable_list(struct flowtable *ft, uint32_t hash)
428 {
429
430 CRITICAL_ASSERT(curthread);
431 return (zpcpu_get(ft->ft_table[hash % ft->ft_size]));
432 }
433
434 static int
flow_stale(struct flowtable * ft,struct flentry * fle,int maxidle)435 flow_stale(struct flowtable *ft, struct flentry *fle, int maxidle)
436 {
437
438 if (((fle->f_rt->rt_flags & RTF_HOST) &&
439 ((fle->f_rt->rt_flags & (RTF_UP)) != (RTF_UP))) ||
440 (fle->f_rt->rt_ifp == NULL) ||
441 !RT_LINK_IS_UP(fle->f_rt->rt_ifp) ||
442 (fle->f_lle->la_flags & LLE_VALID) == 0)
443 return (1);
444
445 if (time_uptime - fle->f_uptime > maxidle)
446 return (1);
447
448 #ifdef FLOWTABLE_HASH_ALL
449 if (fle->f_flags & FL_STALE)
450 return (1);
451 #endif
452
453 return (0);
454 }
455
456 static int
flow_full(void)457 flow_full(void)
458 {
459 int count, max;
460
461 count = uma_zone_get_cur(flow_zone);
462 max = uma_zone_get_max(flow_zone);
463
464 return (count > (max - (max >> 3)));
465 }
466
467 static int
flow_matches(struct flentry * fle,uint32_t * key,int keylen,uint32_t fibnum)468 flow_matches(struct flentry *fle, uint32_t *key, int keylen, uint32_t fibnum)
469 {
470 #ifdef FLOWTABLE_HASH_ALL
471 uint8_t proto;
472
473 proto = (fibnum >> 16) & 0xff;
474 fibnum &= 0xffff;
475 #endif
476
477 CRITICAL_ASSERT(curthread);
478
479 /* Microoptimization for IPv4: don't use bcmp(). */
480 if (((keylen == sizeof(uint32_t) && (fle->f_key[0] != key[0])) ||
481 (bcmp(fle->f_key, key, keylen) == 0)) &&
482 fibnum == fle->f_fibnum &&
483 #ifdef FLOWTABLE_HASH_ALL
484 proto == fle->f_proto &&
485 #endif
486 (fle->f_rt->rt_flags & RTF_UP) &&
487 fle->f_rt->rt_ifp != NULL &&
488 (fle->f_lle->la_flags & LLE_VALID))
489 return (1);
490
491 return (0);
492 }
493
494 static struct flentry *
flowtable_insert(struct flowtable * ft,uint32_t hash,uint32_t * key,int keylen,uint32_t fibnum0)495 flowtable_insert(struct flowtable *ft, uint32_t hash, uint32_t *key,
496 int keylen, uint32_t fibnum0)
497 {
498 #ifdef INET6
499 struct route_in6 sro6;
500 #endif
501 #ifdef INET
502 struct route sro;
503 #endif
504 struct route *ro = NULL;
505 struct rtentry *rt;
506 struct lltable *lt = NULL;
507 struct llentry *lle;
508 struct sockaddr_storage *l3addr;
509 struct ifnet *ifp;
510 struct flist *flist;
511 struct flentry *fle, *iter;
512 bitstr_t *mask;
513 uint16_t fibnum = fibnum0;
514 #ifdef FLOWTABLE_HASH_ALL
515 uint8_t proto;
516
517 proto = (fibnum0 >> 16) & 0xff;
518 fibnum = fibnum0 & 0xffff;
519 #endif
520
521 /*
522 * This bit of code ends up locking the
523 * same route 3 times (just like ip_output + ether_output)
524 * - at lookup
525 * - in rt_check when called by arpresolve
526 * - dropping the refcount for the rtentry
527 *
528 * This could be consolidated to one if we wrote a variant
529 * of arpresolve with an rt_check variant that expected to
530 * receive the route locked
531 */
532 #ifdef INET
533 if (ft == &V_ip4_ft) {
534 struct sockaddr_in *sin;
535
536 ro = &sro;
537 bzero(&sro.ro_dst, sizeof(sro.ro_dst));
538
539 sin = (struct sockaddr_in *)&sro.ro_dst;
540 sin->sin_family = AF_INET;
541 sin->sin_len = sizeof(*sin);
542 sin->sin_addr.s_addr = key[0];
543 }
544 #endif
545 #ifdef INET6
546 if (ft == &V_ip6_ft) {
547 struct sockaddr_in6 *sin6;
548
549 ro = (struct route *)&sro6;
550 sin6 = &sro6.ro_dst;
551
552 bzero(sin6, sizeof(*sin6));
553 sin6->sin6_family = AF_INET6;
554 sin6->sin6_len = sizeof(*sin6);
555 bcopy(key, &sin6->sin6_addr, sizeof(struct in6_addr));
556 }
557 #endif
558
559 ro->ro_rt = NULL;
560 #ifdef RADIX_MPATH
561 rtalloc_mpath_fib(ro, hash, fibnum);
562 #else
563 rtalloc_ign_fib(ro, 0, fibnum);
564 #endif
565 if (ro->ro_rt == NULL)
566 return (NULL);
567
568 rt = ro->ro_rt;
569 ifp = rt->rt_ifp;
570
571 if (ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) {
572 RTFREE(rt);
573 return (NULL);
574 }
575
576 #ifdef INET
577 if (ft == &V_ip4_ft)
578 lt = LLTABLE(ifp);
579 #endif
580 #ifdef INET6
581 if (ft == &V_ip6_ft)
582 lt = LLTABLE6(ifp);
583 #endif
584
585 if (rt->rt_flags & RTF_GATEWAY)
586 l3addr = (struct sockaddr_storage *)rt->rt_gateway;
587 else
588 l3addr = (struct sockaddr_storage *)&ro->ro_dst;
589 lle = llentry_alloc(ifp, lt, l3addr);
590
591 if (lle == NULL) {
592 RTFREE(rt);
593 return (NULL);
594 }
595
596 /* Don't insert the entry if the ARP hasn't yet finished resolving. */
597 if ((lle->la_flags & LLE_VALID) == 0) {
598 RTFREE(rt);
599 LLE_FREE(lle);
600 FLOWSTAT_INC(ft, ft_fail_lle_invalid);
601 return (NULL);
602 }
603
604 fle = uma_zalloc(flow_zone, M_NOWAIT | M_ZERO);
605 if (fle == NULL) {
606 RTFREE(rt);
607 LLE_FREE(lle);
608 return (NULL);
609 }
610
611 fle->f_hash = hash;
612 bcopy(key, &fle->f_key, keylen);
613 fle->f_rt = rt;
614 fle->f_lle = lle;
615 fle->f_fibnum = fibnum;
616 fle->f_uptime = time_uptime;
617 #ifdef FLOWTABLE_HASH_ALL
618 fle->f_proto = proto;
619 fle->f_flags = fibnum0 >> 24;
620 #endif
621
622 critical_enter();
623 mask = flowtable_mask(ft);
624 flist = flowtable_list(ft, hash);
625
626 if (SLIST_EMPTY(flist)) {
627 bit_set(mask, (hash % ft->ft_size));
628 SLIST_INSERT_HEAD(flist, fle, f_next);
629 goto skip;
630 }
631
632 /*
633 * find end of list and make sure that we were not
634 * preempted by another thread handling this flow
635 */
636 SLIST_FOREACH(iter, flist, f_next) {
637 KASSERT(iter->f_hash % ft->ft_size == hash % ft->ft_size,
638 ("%s: wrong hash", __func__));
639 if (flow_matches(iter, key, keylen, fibnum)) {
640 /*
641 * We probably migrated to an other CPU after
642 * lookup in flowtable_lookup_common() failed.
643 * It appeared that this CPU already has flow
644 * entry.
645 */
646 iter->f_uptime = time_uptime;
647 #ifdef FLOWTABLE_HASH_ALL
648 iter->f_flags |= fibnum >> 24;
649 #endif
650 critical_exit();
651 FLOWSTAT_INC(ft, ft_collisions);
652 uma_zfree(flow_zone, fle);
653 return (iter);
654 }
655 }
656
657 SLIST_INSERT_HEAD(flist, fle, f_next);
658 skip:
659 critical_exit();
660 FLOWSTAT_INC(ft, ft_inserts);
661
662 return (fle);
663 }
664
665 int
flowtable_lookup(sa_family_t sa,struct mbuf * m,struct route * ro)666 flowtable_lookup(sa_family_t sa, struct mbuf *m, struct route *ro)
667 {
668 struct flentry *fle;
669
670 if (V_flowtable_enable == 0)
671 return (ENXIO);
672
673 switch (sa) {
674 #ifdef INET
675 case AF_INET:
676 fle = flowtable_lookup_ipv4(m, ro);
677 break;
678 #endif
679 #ifdef INET6
680 case AF_INET6:
681 fle = flowtable_lookup_ipv6(m, ro);
682 break;
683 #endif
684 default:
685 panic("%s: sa %d", __func__, sa);
686 }
687
688 if (fle == NULL)
689 return (EHOSTUNREACH);
690
691 if (M_HASHTYPE_GET(m) == M_HASHTYPE_NONE) {
692 M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE);
693 m->m_pkthdr.flowid = fle->f_hash;
694 }
695
696 ro->ro_rt = fle->f_rt;
697 ro->ro_lle = fle->f_lle;
698 ro->ro_flags |= RT_NORTREF;
699
700 return (0);
701 }
702
703 static struct flentry *
flowtable_lookup_common(struct flowtable * ft,uint32_t * key,int keylen,uint32_t fibnum)704 flowtable_lookup_common(struct flowtable *ft, uint32_t *key, int keylen,
705 uint32_t fibnum)
706 {
707 struct flist *flist;
708 struct flentry *fle;
709 uint32_t hash;
710
711 FLOWSTAT_INC(ft, ft_lookups);
712
713 hash = jenkins_hash32(key, keylen / sizeof(uint32_t), flow_hashjitter);
714
715 critical_enter();
716 flist = flowtable_list(ft, hash);
717 SLIST_FOREACH(fle, flist, f_next) {
718 KASSERT(fle->f_hash % ft->ft_size == hash % ft->ft_size,
719 ("%s: wrong hash", __func__));
720 if (flow_matches(fle, key, keylen, fibnum)) {
721 fle->f_uptime = time_uptime;
722 #ifdef FLOWTABLE_HASH_ALL
723 fle->f_flags |= fibnum >> 24;
724 #endif
725 critical_exit();
726 FLOWSTAT_INC(ft, ft_hits);
727 return (fle);
728 }
729 }
730 critical_exit();
731
732 FLOWSTAT_INC(ft, ft_misses);
733
734 return (flowtable_insert(ft, hash, key, keylen, fibnum));
735 }
736
737 /*
738 * used by the bit_alloc macro
739 */
740 #define calloc(count, size) malloc((count)*(size), M_FTABLE, M_WAITOK | M_ZERO)
741 static void
flowtable_alloc(struct flowtable * ft)742 flowtable_alloc(struct flowtable *ft)
743 {
744
745 ft->ft_table = malloc(ft->ft_size * sizeof(struct flist),
746 M_FTABLE, M_WAITOK);
747 for (int i = 0; i < ft->ft_size; i++)
748 ft->ft_table[i] = uma_zalloc(pcpu_zone_ptr, M_WAITOK | M_ZERO);
749
750 ft->ft_masks = uma_zalloc(pcpu_zone_ptr, M_WAITOK);
751 for (int i = 0; i < mp_ncpus; i++) {
752 bitstr_t **b;
753
754 b = zpcpu_get_cpu(ft->ft_masks, i);
755 *b = bit_alloc(ft->ft_size);
756 }
757 ft->ft_tmpmask = bit_alloc(ft->ft_size);
758 }
759 #undef calloc
760
761 static void
flowtable_free_stale(struct flowtable * ft,struct rtentry * rt,int maxidle)762 flowtable_free_stale(struct flowtable *ft, struct rtentry *rt, int maxidle)
763 {
764 struct flist *flist, freelist;
765 struct flentry *fle, *fle1, *fleprev;
766 bitstr_t *mask, *tmpmask;
767 int curbit, tmpsize;
768
769 SLIST_INIT(&freelist);
770 mask = flowtable_mask(ft);
771 tmpmask = ft->ft_tmpmask;
772 tmpsize = ft->ft_size;
773 memcpy(tmpmask, mask, ft->ft_size/8);
774 curbit = 0;
775 fleprev = NULL; /* pacify gcc */
776 /*
777 * XXX Note to self, bit_ffs operates at the byte level
778 * and thus adds gratuitous overhead
779 */
780 bit_ffs(tmpmask, ft->ft_size, &curbit);
781 while (curbit != -1) {
782 if (curbit >= ft->ft_size || curbit < -1) {
783 log(LOG_ALERT,
784 "warning: bad curbit value %d \n",
785 curbit);
786 break;
787 }
788
789 FLOWSTAT_INC(ft, ft_free_checks);
790
791 critical_enter();
792 flist = flowtable_list(ft, curbit);
793 #ifdef DIAGNOSTIC
794 if (SLIST_EMPTY(flist) && curbit > 0) {
795 log(LOG_ALERT,
796 "warning bit=%d set, but no fle found\n",
797 curbit);
798 }
799 #endif
800 SLIST_FOREACH_SAFE(fle, flist, f_next, fle1) {
801 if (rt != NULL && fle->f_rt != rt) {
802 fleprev = fle;
803 continue;
804 }
805 if (!flow_stale(ft, fle, maxidle)) {
806 fleprev = fle;
807 continue;
808 }
809
810 if (fle == SLIST_FIRST(flist))
811 SLIST_REMOVE_HEAD(flist, f_next);
812 else
813 SLIST_REMOVE_AFTER(fleprev, f_next);
814 SLIST_INSERT_HEAD(&freelist, fle, f_next);
815 }
816 if (SLIST_EMPTY(flist))
817 bit_clear(mask, curbit);
818 critical_exit();
819
820 bit_clear(tmpmask, curbit);
821 tmpmask += (curbit / 8);
822 tmpsize -= (curbit / 8) * 8;
823 bit_ffs(tmpmask, tmpsize, &curbit);
824 }
825
826 SLIST_FOREACH_SAFE(fle, &freelist, f_next, fle1) {
827 FLOWSTAT_INC(ft, ft_frees);
828 if (fle->f_rt != NULL)
829 RTFREE(fle->f_rt);
830 if (fle->f_lle != NULL)
831 LLE_FREE(fle->f_lle);
832 uma_zfree(flow_zone, fle);
833 }
834 }
835
836 static void
flowtable_clean_vnet(struct flowtable * ft,struct rtentry * rt,int maxidle)837 flowtable_clean_vnet(struct flowtable *ft, struct rtentry *rt, int maxidle)
838 {
839 int i;
840
841 CPU_FOREACH(i) {
842 if (smp_started == 1) {
843 thread_lock(curthread);
844 sched_bind(curthread, i);
845 thread_unlock(curthread);
846 }
847
848 flowtable_free_stale(ft, rt, maxidle);
849
850 if (smp_started == 1) {
851 thread_lock(curthread);
852 sched_unbind(curthread);
853 thread_unlock(curthread);
854 }
855 }
856 }
857
858 void
flowtable_route_flush(sa_family_t sa,struct rtentry * rt)859 flowtable_route_flush(sa_family_t sa, struct rtentry *rt)
860 {
861 struct flowtable *ft;
862
863 switch (sa) {
864 #ifdef INET
865 case AF_INET:
866 ft = &V_ip4_ft;
867 break;
868 #endif
869 #ifdef INET6
870 case AF_INET6:
871 ft = &V_ip6_ft;
872 break;
873 #endif
874 default:
875 panic("%s: sa %d", __func__, sa);
876 }
877
878 flowtable_clean_vnet(ft, rt, 0);
879 }
880
881 static void
flowtable_cleaner(void)882 flowtable_cleaner(void)
883 {
884 VNET_ITERATOR_DECL(vnet_iter);
885 struct thread *td;
886
887 if (bootverbose)
888 log(LOG_INFO, "flowtable cleaner started\n");
889 td = curthread;
890 while (1) {
891 uint32_t flowclean_freq, maxidle;
892
893 /*
894 * The maximum idle time, as well as frequency are arbitrary.
895 */
896 if (flow_full())
897 maxidle = 5;
898 else
899 maxidle = 30;
900
901 VNET_LIST_RLOCK();
902 VNET_FOREACH(vnet_iter) {
903 CURVNET_SET(vnet_iter);
904 #ifdef INET
905 flowtable_clean_vnet(&V_ip4_ft, NULL, maxidle);
906 #endif
907 #ifdef INET6
908 flowtable_clean_vnet(&V_ip6_ft, NULL, maxidle);
909 #endif
910 CURVNET_RESTORE();
911 }
912 VNET_LIST_RUNLOCK();
913
914 if (flow_full())
915 flowclean_freq = 4*hz;
916 else
917 flowclean_freq = 20*hz;
918 mtx_lock(&flowclean_lock);
919 thread_lock(td);
920 sched_prio(td, PPAUSE);
921 thread_unlock(td);
922 flowclean_cycles++;
923 cv_broadcast(&flowclean_f_cv);
924 cv_timedwait(&flowclean_c_cv, &flowclean_lock, flowclean_freq);
925 mtx_unlock(&flowclean_lock);
926 }
927 }
928
929 static void
flowtable_flush(void * unused __unused)930 flowtable_flush(void *unused __unused)
931 {
932 uint64_t start;
933
934 mtx_lock(&flowclean_lock);
935 start = flowclean_cycles;
936 while (start == flowclean_cycles) {
937 cv_broadcast(&flowclean_c_cv);
938 cv_wait(&flowclean_f_cv, &flowclean_lock);
939 }
940 mtx_unlock(&flowclean_lock);
941 }
942
943 static struct kproc_desc flow_kp = {
944 "flowcleaner",
945 flowtable_cleaner,
946 &flowcleanerproc
947 };
948 SYSINIT(flowcleaner, SI_SUB_KTHREAD_IDLE, SI_ORDER_ANY, kproc_start, &flow_kp);
949
950 static int
flowtable_get_size(char * name)951 flowtable_get_size(char *name)
952 {
953 int size;
954
955 if (TUNABLE_INT_FETCH(name, &size)) {
956 if (size < 256)
957 size = 256;
958 if (!powerof2(size)) {
959 printf("%s must be power of 2\n", name);
960 size = 2048;
961 }
962 } else {
963 /*
964 * round up to the next power of 2
965 */
966 size = 1 << fls((1024 + maxusers * 64) - 1);
967 }
968
969 return (size);
970 }
971
972 static void
flowtable_init(const void * unused __unused)973 flowtable_init(const void *unused __unused)
974 {
975
976 flow_hashjitter = arc4random();
977
978 flow_zone = uma_zcreate("flows", sizeof(struct flentry),
979 NULL, NULL, NULL, NULL, (64-1), UMA_ZONE_MAXBUCKET);
980 uma_zone_set_max(flow_zone, 1024 + maxusers * 64 * mp_ncpus);
981
982 cv_init(&flowclean_c_cv, "c_flowcleanwait");
983 cv_init(&flowclean_f_cv, "f_flowcleanwait");
984 mtx_init(&flowclean_lock, "flowclean lock", NULL, MTX_DEF);
985 EVENTHANDLER_REGISTER(ifnet_departure_event, flowtable_flush, NULL,
986 EVENTHANDLER_PRI_ANY);
987 }
988 SYSINIT(flowtable_init, SI_SUB_PROTO_BEGIN, SI_ORDER_FIRST,
989 flowtable_init, NULL);
990
991 #ifdef INET
992 static SYSCTL_NODE(_net_flowtable, OID_AUTO, ip4, CTLFLAG_RD, NULL,
993 "Flowtable for IPv4");
994
995 static VNET_PCPUSTAT_DEFINE(struct flowtable_stat, ip4_ftstat);
996 VNET_PCPUSTAT_SYSINIT(ip4_ftstat);
997 VNET_PCPUSTAT_SYSUNINIT(ip4_ftstat);
998 SYSCTL_VNET_PCPUSTAT(_net_flowtable_ip4, OID_AUTO, stat, struct flowtable_stat,
999 ip4_ftstat, "Flowtable statistics for IPv4 "
1000 "(struct flowtable_stat, net/flowtable.h)");
1001
1002 static void
flowtable_init_vnet_v4(const void * unused __unused)1003 flowtable_init_vnet_v4(const void *unused __unused)
1004 {
1005
1006 V_ip4_ft.ft_size = flowtable_get_size("net.flowtable.ip4.size");
1007 V_ip4_ft.ft_stat = VNET(ip4_ftstat);
1008 flowtable_alloc(&V_ip4_ft);
1009 }
1010 VNET_SYSINIT(ft_vnet_v4, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY,
1011 flowtable_init_vnet_v4, NULL);
1012 #endif /* INET */
1013
1014 #ifdef INET6
1015 static SYSCTL_NODE(_net_flowtable, OID_AUTO, ip6, CTLFLAG_RD, NULL,
1016 "Flowtable for IPv6");
1017
1018 static VNET_PCPUSTAT_DEFINE(struct flowtable_stat, ip6_ftstat);
1019 VNET_PCPUSTAT_SYSINIT(ip6_ftstat);
1020 VNET_PCPUSTAT_SYSUNINIT(ip6_ftstat);
1021 SYSCTL_VNET_PCPUSTAT(_net_flowtable_ip6, OID_AUTO, stat, struct flowtable_stat,
1022 ip6_ftstat, "Flowtable statistics for IPv6 "
1023 "(struct flowtable_stat, net/flowtable.h)");
1024
1025 static void
flowtable_init_vnet_v6(const void * unused __unused)1026 flowtable_init_vnet_v6(const void *unused __unused)
1027 {
1028
1029 V_ip6_ft.ft_size = flowtable_get_size("net.flowtable.ip6.size");
1030 V_ip6_ft.ft_stat = VNET(ip6_ftstat);
1031 flowtable_alloc(&V_ip6_ft);
1032 }
1033 VNET_SYSINIT(flowtable_init_vnet_v6, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY,
1034 flowtable_init_vnet_v6, NULL);
1035 #endif /* INET6 */
1036
1037 #ifdef DDB
1038 static bitstr_t *
flowtable_mask_pcpu(struct flowtable * ft,int cpuid)1039 flowtable_mask_pcpu(struct flowtable *ft, int cpuid)
1040 {
1041
1042 return (zpcpu_get_cpu(*ft->ft_masks, cpuid));
1043 }
1044
1045 static struct flist *
flowtable_list_pcpu(struct flowtable * ft,uint32_t hash,int cpuid)1046 flowtable_list_pcpu(struct flowtable *ft, uint32_t hash, int cpuid)
1047 {
1048
1049 return (zpcpu_get_cpu(&ft->ft_table[hash % ft->ft_size], cpuid));
1050 }
1051
1052 static void
flow_show(struct flowtable * ft,struct flentry * fle)1053 flow_show(struct flowtable *ft, struct flentry *fle)
1054 {
1055 int idle_time;
1056 int rt_valid, ifp_valid;
1057 volatile struct rtentry *rt;
1058 struct ifnet *ifp = NULL;
1059 uint32_t *hashkey = fle->f_key;
1060
1061 idle_time = (int)(time_uptime - fle->f_uptime);
1062 rt = fle->f_rt;
1063 rt_valid = rt != NULL;
1064 if (rt_valid)
1065 ifp = rt->rt_ifp;
1066 ifp_valid = ifp != NULL;
1067
1068 #ifdef INET
1069 if (ft == &V_ip4_ft) {
1070 char daddr[4*sizeof "123"];
1071 #ifdef FLOWTABLE_HASH_ALL
1072 char saddr[4*sizeof "123"];
1073 uint16_t sport, dport;
1074 #endif
1075
1076 inet_ntoa_r(*(struct in_addr *) &hashkey[0], daddr);
1077 #ifdef FLOWTABLE_HASH_ALL
1078 inet_ntoa_r(*(struct in_addr *) &hashkey[1], saddr);
1079 dport = ntohs((uint16_t)(hashkey[2] >> 16));
1080 sport = ntohs((uint16_t)(hashkey[2] & 0xffff));
1081 db_printf("%s:%d->%s:%d", saddr, sport, daddr, dport);
1082 #else
1083 db_printf("%s ", daddr);
1084 #endif
1085 }
1086 #endif /* INET */
1087 #ifdef INET6
1088 if (ft == &V_ip6_ft) {
1089 #ifdef FLOWTABLE_HASH_ALL
1090 db_printf("\n\tkey=%08x:%08x:%08x%08x:%08x:%08x%08x:%08x:%08x",
1091 hashkey[0], hashkey[1], hashkey[2],
1092 hashkey[3], hashkey[4], hashkey[5],
1093 hashkey[6], hashkey[7], hashkey[8]);
1094 #else
1095 db_printf("\n\tkey=%08x:%08x:%08x ",
1096 hashkey[0], hashkey[1], hashkey[2]);
1097 #endif
1098 }
1099 #endif /* INET6 */
1100
1101 db_printf("hash=%08x idle_time=%03d"
1102 "\n\tfibnum=%02d rt=%p",
1103 fle->f_hash, idle_time, fle->f_fibnum, fle->f_rt);
1104
1105 #ifdef FLOWTABLE_HASH_ALL
1106 if (fle->f_flags & FL_STALE)
1107 db_printf(" FL_STALE ");
1108 #endif
1109 if (rt_valid) {
1110 if (rt->rt_flags & RTF_UP)
1111 db_printf(" RTF_UP ");
1112 }
1113 if (ifp_valid) {
1114 if (ifp->if_flags & IFF_LOOPBACK)
1115 db_printf(" IFF_LOOPBACK ");
1116 if (ifp->if_flags & IFF_UP)
1117 db_printf(" IFF_UP ");
1118 if (ifp->if_flags & IFF_POINTOPOINT)
1119 db_printf(" IFF_POINTOPOINT ");
1120 }
1121 db_printf("\n");
1122 }
1123
1124 static void
flowtable_show(struct flowtable * ft,int cpuid)1125 flowtable_show(struct flowtable *ft, int cpuid)
1126 {
1127 int curbit = 0;
1128 bitstr_t *mask, *tmpmask;
1129
1130 if (cpuid != -1)
1131 db_printf("cpu: %d\n", cpuid);
1132 mask = flowtable_mask_pcpu(ft, cpuid);
1133 tmpmask = ft->ft_tmpmask;
1134 memcpy(tmpmask, mask, ft->ft_size/8);
1135 /*
1136 * XXX Note to self, bit_ffs operates at the byte level
1137 * and thus adds gratuitous overhead
1138 */
1139 bit_ffs(tmpmask, ft->ft_size, &curbit);
1140 while (curbit != -1) {
1141 struct flist *flist;
1142 struct flentry *fle;
1143
1144 if (curbit >= ft->ft_size || curbit < -1) {
1145 db_printf("warning: bad curbit value %d \n",
1146 curbit);
1147 break;
1148 }
1149
1150 flist = flowtable_list_pcpu(ft, curbit, cpuid);
1151
1152 SLIST_FOREACH(fle, flist, f_next)
1153 flow_show(ft, fle);
1154 bit_clear(tmpmask, curbit);
1155 bit_ffs(tmpmask, ft->ft_size, &curbit);
1156 }
1157 }
1158
1159 static void
flowtable_show_vnet(struct flowtable * ft)1160 flowtable_show_vnet(struct flowtable *ft)
1161 {
1162
1163 int i;
1164
1165 CPU_FOREACH(i)
1166 flowtable_show(ft, i);
1167 }
1168
DB_SHOW_COMMAND(flowtables,db_show_flowtables)1169 DB_SHOW_COMMAND(flowtables, db_show_flowtables)
1170 {
1171 VNET_ITERATOR_DECL(vnet_iter);
1172
1173 VNET_FOREACH(vnet_iter) {
1174 CURVNET_SET(vnet_iter);
1175 #ifdef VIMAGE
1176 db_printf("vnet %p\n", vnet_iter);
1177 #endif
1178 #ifdef INET
1179 printf("IPv4:\n");
1180 flowtable_show_vnet(&V_ip4_ft);
1181 #endif
1182 #ifdef INET6
1183 printf("IPv6:\n");
1184 flowtable_show_vnet(&V_ip6_ft);
1185 #endif
1186 CURVNET_RESTORE();
1187 }
1188 }
1189 #endif
1190