2 * net/sched/cls_rsvp.h Template file for RSVPv[46] classifiers.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
13 Comparing to general packet classification problem,
14 RSVP needs only sevaral relatively simple rules:
16 * (dst, protocol) are always specified,
17 so that we are able to hash them.
18 * src may be exact, or may be wildcard, so that
19 we can keep a hash table plus one wildcard entry.
20 * source port (or flow label) is important only if src is given.
24 We use a two level hash table: The top level is keyed by
25 destination address and protocol ID, every bucket contains a list
26 of "rsvp sessions", identified by destination address, protocol and
27 DPI(="Destination Port ID"): triple (key, mask, offset).
29 Every bucket has a smaller hash table keyed by source address
30 (cf. RSVP flowspec) and one wildcard entry for wildcard reservations.
31 Every bucket is again a list of "RSVP flows", selected by
32 source address and SPI(="Source Port ID" here rather than
33 "security parameter index"): triple (key, mask, offset).
36 NOTE 1. All the packets with IPv6 extension headers (but AH and ESP)
37 and all fragmented packets go to the best-effort traffic class.
40 NOTE 2. Two "port id"'s seems to be redundant, rfc2207 requires
41 only one "Generalized Port Identifier". So that for classic
42 ah, esp (and udp,tcp) both *pi should coincide or one of them
45 At first sight, this redundancy is just a waste of CPU
46 resources. But DPI and SPI add the possibility to assign different
47 priorities to GPIs. Look also at note 4 about tunnels below.
50 NOTE 3. One complication is the case of tunneled packets.
51 We implement it as following: if the first lookup
52 matches a special session with "tunnelhdr" value not zero,
53 flowid doesn't contain the true flow ID, but the tunnel ID (1...255).
54 In this case, we pull tunnelhdr bytes and restart lookup
55 with tunnel ID added to the list of keys. Simple and stupid 8)8)
56 It's enough for PIMREG and IPIP.
59 NOTE 4. Two GPIs make it possible to parse even GRE packets.
60 F.e. DPI can select ETH_P_IP (and necessary flags to make
61 tunnelhdr correct) in GRE protocol field and SPI matches
62 GRE key. Is it not nice? 8)8)
65 Well, as result, despite its simplicity, we get a pretty
66 powerful classification engine. */
73 struct rsvp_session __rcu
*ht
[256];
78 struct rsvp_session __rcu
*next
;
79 __be32 dst
[RSVP_DST_LEN
];
80 struct tc_rsvp_gpi dpi
;
83 /* 16 (src,sport) hash slots, and one wildcard source slot */
84 struct rsvp_filter __rcu
*ht
[16 + 1];
90 struct rsvp_filter __rcu
*next
;
91 __be32 src
[RSVP_DST_LEN
];
92 struct tc_rsvp_gpi spi
;
95 struct tcf_result res
;
99 struct rsvp_session
*sess
;
103 static inline unsigned int hash_dst(__be32
*dst
, u8 protocol
, u8 tunnelid
)
105 unsigned int h
= (__force __u32
)dst
[RSVP_DST_LEN
- 1];
109 return (h
^ protocol
^ tunnelid
) & 0xFF;
112 static inline unsigned int hash_src(__be32
*src
)
114 unsigned int h
= (__force __u32
)src
[RSVP_DST_LEN
-1];
122 #define RSVP_APPLY_RESULT() \
124 int r = tcf_exts_exec(skb, &f->exts, res); \
131 static int rsvp_classify(struct sk_buff
*skb
, const struct tcf_proto
*tp
,
132 struct tcf_result
*res
)
134 struct rsvp_head
*head
= rcu_dereference_bh(tp
->root
);
135 struct rsvp_session
*s
;
136 struct rsvp_filter
*f
;
142 #if RSVP_DST_LEN == 4
143 struct ipv6hdr
*nhptr
;
145 if (!pskb_network_may_pull(skb
, sizeof(*nhptr
)))
147 nhptr
= ipv6_hdr(skb
);
151 if (!pskb_network_may_pull(skb
, sizeof(*nhptr
)))
158 #if RSVP_DST_LEN == 4
159 src
= &nhptr
->saddr
.s6_addr32
[0];
160 dst
= &nhptr
->daddr
.s6_addr32
[0];
161 protocol
= nhptr
->nexthdr
;
162 xprt
= ((u8
*)nhptr
) + sizeof(struct ipv6hdr
);
166 protocol
= nhptr
->protocol
;
167 xprt
= ((u8
*)nhptr
) + (nhptr
->ihl
<<2);
168 if (ip_is_fragment(nhptr
))
172 h1
= hash_dst(dst
, protocol
, tunnelid
);
175 for (s
= rcu_dereference_bh(head
->ht
[h1
]); s
;
176 s
= rcu_dereference_bh(s
->next
)) {
177 if (dst
[RSVP_DST_LEN
-1] == s
->dst
[RSVP_DST_LEN
- 1] &&
178 protocol
== s
->protocol
&&
180 (*(u32
*)(xprt
+ s
->dpi
.offset
) ^ s
->dpi
.key
)) &&
181 #if RSVP_DST_LEN == 4
182 dst
[0] == s
->dst
[0] &&
183 dst
[1] == s
->dst
[1] &&
184 dst
[2] == s
->dst
[2] &&
186 tunnelid
== s
->tunnelid
) {
188 for (f
= rcu_dereference_bh(s
->ht
[h2
]); f
;
189 f
= rcu_dereference_bh(f
->next
)) {
190 if (src
[RSVP_DST_LEN
-1] == f
->src
[RSVP_DST_LEN
- 1] &&
191 !(f
->spi
.mask
& (*(u32
*)(xprt
+ f
->spi
.offset
) ^ f
->spi
.key
))
192 #if RSVP_DST_LEN == 4
194 src
[0] == f
->src
[0] &&
195 src
[1] == f
->src
[1] &&
203 if (f
->tunnelhdr
== 0)
206 tunnelid
= f
->res
.classid
;
207 nhptr
= (void *)(xprt
+ f
->tunnelhdr
- sizeof(*nhptr
));
212 /* And wildcard bucket... */
213 for (f
= rcu_dereference_bh(s
->ht
[16]); f
;
214 f
= rcu_dereference_bh(f
->next
)) {
225 static void rsvp_replace(struct tcf_proto
*tp
, struct rsvp_filter
*n
, u32 h
)
227 struct rsvp_head
*head
= rtnl_dereference(tp
->root
);
228 struct rsvp_session
*s
;
229 struct rsvp_filter __rcu
**ins
;
230 struct rsvp_filter
*pins
;
231 unsigned int h1
= h
& 0xFF;
232 unsigned int h2
= (h
>> 8) & 0xFF;
234 for (s
= rtnl_dereference(head
->ht
[h1
]); s
;
235 s
= rtnl_dereference(s
->next
)) {
236 for (ins
= &s
->ht
[h2
], pins
= rtnl_dereference(*ins
); ;
237 ins
= &pins
->next
, pins
= rtnl_dereference(*ins
)) {
238 if (pins
->handle
== h
) {
239 RCU_INIT_POINTER(n
->next
, pins
->next
);
240 rcu_assign_pointer(*ins
, n
);
246 /* Something went wrong if we are trying to replace a non-existant
247 * node. Mind as well halt instead of silently failing.
252 static unsigned long rsvp_get(struct tcf_proto
*tp
, u32 handle
)
254 struct rsvp_head
*head
= rtnl_dereference(tp
->root
);
255 struct rsvp_session
*s
;
256 struct rsvp_filter
*f
;
257 unsigned int h1
= handle
& 0xFF;
258 unsigned int h2
= (handle
>> 8) & 0xFF;
263 for (s
= rtnl_dereference(head
->ht
[h1
]); s
;
264 s
= rtnl_dereference(s
->next
)) {
265 for (f
= rtnl_dereference(s
->ht
[h2
]); f
;
266 f
= rtnl_dereference(f
->next
)) {
267 if (f
->handle
== handle
)
268 return (unsigned long)f
;
274 static int rsvp_init(struct tcf_proto
*tp
)
276 struct rsvp_head
*data
;
278 data
= kzalloc(sizeof(struct rsvp_head
), GFP_KERNEL
);
280 rcu_assign_pointer(tp
->root
, data
);
287 rsvp_delete_filter(struct tcf_proto
*tp
, struct rsvp_filter
*f
)
289 tcf_unbind_filter(tp
, &f
->res
);
290 tcf_exts_destroy(&f
->exts
);
294 static void rsvp_destroy(struct tcf_proto
*tp
)
296 struct rsvp_head
*data
= rtnl_dereference(tp
->root
);
302 RCU_INIT_POINTER(tp
->root
, NULL
);
304 for (h1
= 0; h1
< 256; h1
++) {
305 struct rsvp_session
*s
;
307 while ((s
= rtnl_dereference(data
->ht
[h1
])) != NULL
) {
308 RCU_INIT_POINTER(data
->ht
[h1
], s
->next
);
310 for (h2
= 0; h2
<= 16; h2
++) {
311 struct rsvp_filter
*f
;
313 while ((f
= rtnl_dereference(s
->ht
[h2
])) != NULL
) {
314 rcu_assign_pointer(s
->ht
[h2
], f
->next
);
315 rsvp_delete_filter(tp
, f
);
321 kfree_rcu(data
, rcu
);
324 static int rsvp_delete(struct tcf_proto
*tp
, unsigned long arg
)
326 struct rsvp_head
*head
= rtnl_dereference(tp
->root
);
327 struct rsvp_filter
*nfp
, *f
= (struct rsvp_filter
*)arg
;
328 struct rsvp_filter __rcu
**fp
;
329 unsigned int h
= f
->handle
;
330 struct rsvp_session __rcu
**sp
;
331 struct rsvp_session
*nsp
, *s
= f
->sess
;
334 fp
= &s
->ht
[(h
>> 8) & 0xFF];
335 for (nfp
= rtnl_dereference(*fp
); nfp
;
336 fp
= &nfp
->next
, nfp
= rtnl_dereference(*fp
)) {
338 RCU_INIT_POINTER(*fp
, f
->next
);
339 rsvp_delete_filter(tp
, f
);
343 for (i
= 0; i
<= 16; i
++)
347 /* OK, session has no flows */
348 sp
= &head
->ht
[h
& 0xFF];
349 for (nsp
= rtnl_dereference(*sp
); nsp
;
350 sp
= &nsp
->next
, nsp
= rtnl_dereference(*sp
)) {
352 RCU_INIT_POINTER(*sp
, s
->next
);
364 static unsigned int gen_handle(struct tcf_proto
*tp
, unsigned salt
)
366 struct rsvp_head
*data
= rtnl_dereference(tp
->root
);
372 if ((data
->hgenerator
+= 0x10000) == 0)
373 data
->hgenerator
= 0x10000;
374 h
= data
->hgenerator
|salt
;
375 if (rsvp_get(tp
, h
) == 0)
381 static int tunnel_bts(struct rsvp_head
*data
)
383 int n
= data
->tgenerator
>> 5;
384 u32 b
= 1 << (data
->tgenerator
& 0x1F);
386 if (data
->tmap
[n
] & b
)
392 static void tunnel_recycle(struct rsvp_head
*data
)
394 struct rsvp_session __rcu
**sht
= data
->ht
;
398 memset(tmap
, 0, sizeof(tmap
));
400 for (h1
= 0; h1
< 256; h1
++) {
401 struct rsvp_session
*s
;
402 for (s
= rtnl_dereference(sht
[h1
]); s
;
403 s
= rtnl_dereference(s
->next
)) {
404 for (h2
= 0; h2
<= 16; h2
++) {
405 struct rsvp_filter
*f
;
407 for (f
= rtnl_dereference(s
->ht
[h2
]); f
;
408 f
= rtnl_dereference(f
->next
)) {
409 if (f
->tunnelhdr
== 0)
411 data
->tgenerator
= f
->res
.classid
;
418 memcpy(data
->tmap
, tmap
, sizeof(tmap
));
421 static u32
gen_tunnel(struct rsvp_head
*data
)
425 for (k
= 0; k
< 2; k
++) {
426 for (i
= 255; i
> 0; i
--) {
427 if (++data
->tgenerator
== 0)
428 data
->tgenerator
= 1;
429 if (tunnel_bts(data
))
430 return data
->tgenerator
;
432 tunnel_recycle(data
);
437 static const struct nla_policy rsvp_policy
[TCA_RSVP_MAX
+ 1] = {
438 [TCA_RSVP_CLASSID
] = { .type
= NLA_U32
},
439 [TCA_RSVP_DST
] = { .type
= NLA_BINARY
,
440 .len
= RSVP_DST_LEN
* sizeof(u32
) },
441 [TCA_RSVP_SRC
] = { .type
= NLA_BINARY
,
442 .len
= RSVP_DST_LEN
* sizeof(u32
) },
443 [TCA_RSVP_PINFO
] = { .len
= sizeof(struct tc_rsvp_pinfo
) },
446 static int rsvp_change(struct net
*net
, struct sk_buff
*in_skb
,
447 struct tcf_proto
*tp
, unsigned long base
,
450 unsigned long *arg
, bool ovr
)
452 struct rsvp_head
*data
= rtnl_dereference(tp
->root
);
453 struct rsvp_filter
*f
, *nfp
;
454 struct rsvp_filter __rcu
**fp
;
455 struct rsvp_session
*nsp
, *s
;
456 struct rsvp_session __rcu
**sp
;
457 struct tc_rsvp_pinfo
*pinfo
= NULL
;
458 struct nlattr
*opt
= tca
[TCA_OPTIONS
];
459 struct nlattr
*tb
[TCA_RSVP_MAX
+ 1];
466 return handle
? -EINVAL
: 0;
468 err
= nla_parse_nested(tb
, TCA_RSVP_MAX
, opt
, rsvp_policy
);
472 tcf_exts_init(&e
, TCA_RSVP_ACT
, TCA_RSVP_POLICE
);
473 err
= tcf_exts_validate(net
, tp
, tb
, tca
[TCA_RATE
], &e
, ovr
);
477 f
= (struct rsvp_filter
*)*arg
;
479 /* Node exists: adjust only classid */
480 struct rsvp_filter
*n
;
482 if (f
->handle
!= handle
&& handle
)
485 n
= kmemdup(f
, sizeof(*f
), GFP_KERNEL
);
491 tcf_exts_init(&n
->exts
, TCA_RSVP_ACT
, TCA_RSVP_POLICE
);
493 if (tb
[TCA_RSVP_CLASSID
]) {
494 n
->res
.classid
= nla_get_u32(tb
[TCA_RSVP_CLASSID
]);
495 tcf_bind_filter(tp
, &n
->res
, base
);
498 tcf_exts_change(tp
, &n
->exts
, &e
);
499 rsvp_replace(tp
, n
, handle
);
503 /* Now more serious part... */
507 if (tb
[TCA_RSVP_DST
] == NULL
)
511 f
= kzalloc(sizeof(struct rsvp_filter
), GFP_KERNEL
);
515 tcf_exts_init(&f
->exts
, TCA_RSVP_ACT
, TCA_RSVP_POLICE
);
517 if (tb
[TCA_RSVP_SRC
]) {
518 memcpy(f
->src
, nla_data(tb
[TCA_RSVP_SRC
]), sizeof(f
->src
));
519 h2
= hash_src(f
->src
);
521 if (tb
[TCA_RSVP_PINFO
]) {
522 pinfo
= nla_data(tb
[TCA_RSVP_PINFO
]);
524 f
->tunnelhdr
= pinfo
->tunnelhdr
;
526 if (tb
[TCA_RSVP_CLASSID
])
527 f
->res
.classid
= nla_get_u32(tb
[TCA_RSVP_CLASSID
]);
529 dst
= nla_data(tb
[TCA_RSVP_DST
]);
530 h1
= hash_dst(dst
, pinfo
? pinfo
->protocol
: 0, pinfo
? pinfo
->tunnelid
: 0);
533 if ((f
->handle
= gen_handle(tp
, h1
| (h2
<<8))) == 0)
538 if (f
->res
.classid
> 255)
542 if (f
->res
.classid
== 0 &&
543 (f
->res
.classid
= gen_tunnel(data
)) == 0)
547 for (sp
= &data
->ht
[h1
];
548 (s
= rtnl_dereference(*sp
)) != NULL
;
550 if (dst
[RSVP_DST_LEN
-1] == s
->dst
[RSVP_DST_LEN
-1] &&
551 pinfo
&& pinfo
->protocol
== s
->protocol
&&
552 memcmp(&pinfo
->dpi
, &s
->dpi
, sizeof(s
->dpi
)) == 0 &&
553 #if RSVP_DST_LEN == 4
554 dst
[0] == s
->dst
[0] &&
555 dst
[1] == s
->dst
[1] &&
556 dst
[2] == s
->dst
[2] &&
558 pinfo
->tunnelid
== s
->tunnelid
) {
561 /* OK, we found appropriate session */
566 if (f
->tunnelhdr
== 0)
567 tcf_bind_filter(tp
, &f
->res
, base
);
569 tcf_exts_change(tp
, &f
->exts
, &e
);
572 for (nfp
= rtnl_dereference(*fp
); nfp
;
573 fp
= &nfp
->next
, nfp
= rtnl_dereference(*fp
)) {
574 __u32 mask
= nfp
->spi
.mask
& f
->spi
.mask
;
576 if (mask
!= f
->spi
.mask
)
579 RCU_INIT_POINTER(f
->next
, nfp
);
580 rcu_assign_pointer(*fp
, f
);
582 *arg
= (unsigned long)f
;
587 /* No session found. Create new one. */
590 s
= kzalloc(sizeof(struct rsvp_session
), GFP_KERNEL
);
593 memcpy(s
->dst
, dst
, sizeof(s
->dst
));
597 s
->protocol
= pinfo
->protocol
;
598 s
->tunnelid
= pinfo
->tunnelid
;
601 for (nsp
= rtnl_dereference(*sp
); nsp
;
602 sp
= &nsp
->next
, nsp
= rtnl_dereference(*sp
)) {
603 if ((nsp
->dpi
.mask
& s
->dpi
.mask
) != s
->dpi
.mask
)
606 RCU_INIT_POINTER(s
->next
, nsp
);
607 rcu_assign_pointer(*sp
, s
);
614 tcf_exts_destroy(&e
);
618 static void rsvp_walk(struct tcf_proto
*tp
, struct tcf_walker
*arg
)
620 struct rsvp_head
*head
= rtnl_dereference(tp
->root
);
626 for (h
= 0; h
< 256; h
++) {
627 struct rsvp_session
*s
;
629 for (s
= rtnl_dereference(head
->ht
[h
]); s
;
630 s
= rtnl_dereference(s
->next
)) {
631 for (h1
= 0; h1
<= 16; h1
++) {
632 struct rsvp_filter
*f
;
634 for (f
= rtnl_dereference(s
->ht
[h1
]); f
;
635 f
= rtnl_dereference(f
->next
)) {
636 if (arg
->count
< arg
->skip
) {
640 if (arg
->fn(tp
, (unsigned long)f
, arg
) < 0) {
651 static int rsvp_dump(struct net
*net
, struct tcf_proto
*tp
, unsigned long fh
,
652 struct sk_buff
*skb
, struct tcmsg
*t
)
654 struct rsvp_filter
*f
= (struct rsvp_filter
*)fh
;
655 struct rsvp_session
*s
;
657 struct tc_rsvp_pinfo pinfo
;
663 t
->tcm_handle
= f
->handle
;
665 nest
= nla_nest_start(skb
, TCA_OPTIONS
);
667 goto nla_put_failure
;
669 if (nla_put(skb
, TCA_RSVP_DST
, sizeof(s
->dst
), &s
->dst
))
670 goto nla_put_failure
;
673 pinfo
.protocol
= s
->protocol
;
674 pinfo
.tunnelid
= s
->tunnelid
;
675 pinfo
.tunnelhdr
= f
->tunnelhdr
;
677 if (nla_put(skb
, TCA_RSVP_PINFO
, sizeof(pinfo
), &pinfo
))
678 goto nla_put_failure
;
679 if (f
->res
.classid
&&
680 nla_put_u32(skb
, TCA_RSVP_CLASSID
, f
->res
.classid
))
681 goto nla_put_failure
;
682 if (((f
->handle
>> 8) & 0xFF) != 16 &&
683 nla_put(skb
, TCA_RSVP_SRC
, sizeof(f
->src
), f
->src
))
684 goto nla_put_failure
;
686 if (tcf_exts_dump(skb
, &f
->exts
) < 0)
687 goto nla_put_failure
;
689 nla_nest_end(skb
, nest
);
691 if (tcf_exts_dump_stats(skb
, &f
->exts
) < 0)
692 goto nla_put_failure
;
696 nla_nest_cancel(skb
, nest
);
700 static struct tcf_proto_ops RSVP_OPS __read_mostly
= {
702 .classify
= rsvp_classify
,
704 .destroy
= rsvp_destroy
,
706 .change
= rsvp_change
,
707 .delete = rsvp_delete
,
710 .owner
= THIS_MODULE
,
713 static int __init
init_rsvp(void)
715 return register_tcf_proto_ops(&RSVP_OPS
);
718 static void __exit
exit_rsvp(void)
720 unregister_tcf_proto_ops(&RSVP_OPS
);
723 module_init(init_rsvp
)
724 module_exit(exit_rsvp
)