2 * net/sched/cls_flow.c Generic flow classifier
4 * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/list.h>
15 #include <linux/jhash.h>
16 #include <linux/random.h>
17 #include <linux/pkt_cls.h>
18 #include <linux/skbuff.h>
21 #include <linux/ipv6.h>
22 #include <linux/if_vlan.h>
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <net/inet_sock.h>
27 #include <net/pkt_cls.h>
29 #include <net/route.h>
30 #include <net/flow_dissector.h>
32 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
33 #include <net/netfilter/nf_conntrack.h>
37 struct list_head filters
;
42 struct list_head list
;
44 struct tcf_ematch_tree ematches
;
46 struct timer_list perturb_timer
;
61 struct work_struct work
;
66 static inline u32
addr_fold(void *addr
)
68 unsigned long a
= (unsigned long)addr
;
70 return (a
& 0xFFFFFFFF) ^ (BITS_PER_LONG
> 32 ? a
>> 32 : 0);
73 static u32
flow_get_src(const struct sk_buff
*skb
, const struct flow_keys
*flow
)
75 __be32 src
= flow_get_u32_src(flow
);
80 return addr_fold(skb
->sk
);
83 static u32
flow_get_dst(const struct sk_buff
*skb
, const struct flow_keys
*flow
)
85 __be32 dst
= flow_get_u32_dst(flow
);
90 return addr_fold(skb_dst(skb
)) ^ (__force u16
) tc_skb_protocol(skb
);
93 static u32
flow_get_proto(const struct sk_buff
*skb
,
94 const struct flow_keys
*flow
)
96 return flow
->basic
.ip_proto
;
99 static u32
flow_get_proto_src(const struct sk_buff
*skb
,
100 const struct flow_keys
*flow
)
102 if (flow
->ports
.ports
)
103 return ntohs(flow
->ports
.src
);
105 return addr_fold(skb
->sk
);
108 static u32
flow_get_proto_dst(const struct sk_buff
*skb
,
109 const struct flow_keys
*flow
)
111 if (flow
->ports
.ports
)
112 return ntohs(flow
->ports
.dst
);
114 return addr_fold(skb_dst(skb
)) ^ (__force u16
) tc_skb_protocol(skb
);
117 static u32
flow_get_iif(const struct sk_buff
*skb
)
122 static u32
flow_get_priority(const struct sk_buff
*skb
)
124 return skb
->priority
;
127 static u32
flow_get_mark(const struct sk_buff
*skb
)
132 static u32
flow_get_nfct(const struct sk_buff
*skb
)
134 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
135 return addr_fold(skb_nfct(skb
));
141 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
142 #define CTTUPLE(skb, member) \
144 enum ip_conntrack_info ctinfo; \
145 const struct nf_conn *ct = nf_ct_get(skb, &ctinfo); \
148 ct->tuplehash[CTINFO2DIR(ctinfo)].tuple.member; \
151 #define CTTUPLE(skb, member) \
158 static u32
flow_get_nfct_src(const struct sk_buff
*skb
,
159 const struct flow_keys
*flow
)
161 switch (tc_skb_protocol(skb
)) {
162 case htons(ETH_P_IP
):
163 return ntohl(CTTUPLE(skb
, src
.u3
.ip
));
164 case htons(ETH_P_IPV6
):
165 return ntohl(CTTUPLE(skb
, src
.u3
.ip6
[3]));
168 return flow_get_src(skb
, flow
);
171 static u32
flow_get_nfct_dst(const struct sk_buff
*skb
,
172 const struct flow_keys
*flow
)
174 switch (tc_skb_protocol(skb
)) {
175 case htons(ETH_P_IP
):
176 return ntohl(CTTUPLE(skb
, dst
.u3
.ip
));
177 case htons(ETH_P_IPV6
):
178 return ntohl(CTTUPLE(skb
, dst
.u3
.ip6
[3]));
181 return flow_get_dst(skb
, flow
);
184 static u32
flow_get_nfct_proto_src(const struct sk_buff
*skb
,
185 const struct flow_keys
*flow
)
187 return ntohs(CTTUPLE(skb
, src
.u
.all
));
189 return flow_get_proto_src(skb
, flow
);
192 static u32
flow_get_nfct_proto_dst(const struct sk_buff
*skb
,
193 const struct flow_keys
*flow
)
195 return ntohs(CTTUPLE(skb
, dst
.u
.all
));
197 return flow_get_proto_dst(skb
, flow
);
200 static u32
flow_get_rtclassid(const struct sk_buff
*skb
)
202 #ifdef CONFIG_IP_ROUTE_CLASSID
204 return skb_dst(skb
)->tclassid
;
209 static u32
flow_get_skuid(const struct sk_buff
*skb
)
211 struct sock
*sk
= skb_to_full_sk(skb
);
213 if (sk
&& sk
->sk_socket
&& sk
->sk_socket
->file
) {
214 kuid_t skuid
= sk
->sk_socket
->file
->f_cred
->fsuid
;
216 return from_kuid(&init_user_ns
, skuid
);
221 static u32
flow_get_skgid(const struct sk_buff
*skb
)
223 struct sock
*sk
= skb_to_full_sk(skb
);
225 if (sk
&& sk
->sk_socket
&& sk
->sk_socket
->file
) {
226 kgid_t skgid
= sk
->sk_socket
->file
->f_cred
->fsgid
;
228 return from_kgid(&init_user_ns
, skgid
);
233 static u32
flow_get_vlan_tag(const struct sk_buff
*skb
)
235 u16
uninitialized_var(tag
);
237 if (vlan_get_tag(skb
, &tag
) < 0)
239 return tag
& VLAN_VID_MASK
;
242 static u32
flow_get_rxhash(struct sk_buff
*skb
)
244 return skb_get_hash(skb
);
247 static u32
flow_key_get(struct sk_buff
*skb
, int key
, struct flow_keys
*flow
)
251 return flow_get_src(skb
, flow
);
253 return flow_get_dst(skb
, flow
);
255 return flow_get_proto(skb
, flow
);
256 case FLOW_KEY_PROTO_SRC
:
257 return flow_get_proto_src(skb
, flow
);
258 case FLOW_KEY_PROTO_DST
:
259 return flow_get_proto_dst(skb
, flow
);
261 return flow_get_iif(skb
);
262 case FLOW_KEY_PRIORITY
:
263 return flow_get_priority(skb
);
265 return flow_get_mark(skb
);
267 return flow_get_nfct(skb
);
268 case FLOW_KEY_NFCT_SRC
:
269 return flow_get_nfct_src(skb
, flow
);
270 case FLOW_KEY_NFCT_DST
:
271 return flow_get_nfct_dst(skb
, flow
);
272 case FLOW_KEY_NFCT_PROTO_SRC
:
273 return flow_get_nfct_proto_src(skb
, flow
);
274 case FLOW_KEY_NFCT_PROTO_DST
:
275 return flow_get_nfct_proto_dst(skb
, flow
);
276 case FLOW_KEY_RTCLASSID
:
277 return flow_get_rtclassid(skb
);
279 return flow_get_skuid(skb
);
281 return flow_get_skgid(skb
);
282 case FLOW_KEY_VLAN_TAG
:
283 return flow_get_vlan_tag(skb
);
284 case FLOW_KEY_RXHASH
:
285 return flow_get_rxhash(skb
);
292 #define FLOW_KEYS_NEEDED ((1 << FLOW_KEY_SRC) | \
293 (1 << FLOW_KEY_DST) | \
294 (1 << FLOW_KEY_PROTO) | \
295 (1 << FLOW_KEY_PROTO_SRC) | \
296 (1 << FLOW_KEY_PROTO_DST) | \
297 (1 << FLOW_KEY_NFCT_SRC) | \
298 (1 << FLOW_KEY_NFCT_DST) | \
299 (1 << FLOW_KEY_NFCT_PROTO_SRC) | \
300 (1 << FLOW_KEY_NFCT_PROTO_DST))
302 static int flow_classify(struct sk_buff
*skb
, const struct tcf_proto
*tp
,
303 struct tcf_result
*res
)
305 struct flow_head
*head
= rcu_dereference_bh(tp
->root
);
306 struct flow_filter
*f
;
312 list_for_each_entry_rcu(f
, &head
->filters
, list
) {
313 u32 keys
[FLOW_KEY_MAX
+ 1];
314 struct flow_keys flow_keys
;
316 if (!tcf_em_tree_match(skb
, &f
->ematches
, NULL
))
319 keymask
= f
->keymask
;
320 if (keymask
& FLOW_KEYS_NEEDED
)
321 skb_flow_dissect_flow_keys(skb
, &flow_keys
, 0);
323 for (n
= 0; n
< f
->nkeys
; n
++) {
324 key
= ffs(keymask
) - 1;
325 keymask
&= ~(1 << key
);
326 keys
[n
] = flow_key_get(skb
, key
, &flow_keys
);
329 if (f
->mode
== FLOW_MODE_HASH
)
330 classid
= jhash2(keys
, f
->nkeys
, f
->hashrnd
);
333 classid
= (classid
& f
->mask
) ^ f
->xor;
334 classid
= (classid
>> f
->rshift
) + f
->addend
;
338 classid
%= f
->divisor
;
341 res
->classid
= TC_H_MAKE(f
->baseclass
, f
->baseclass
+ classid
);
343 r
= tcf_exts_exec(skb
, &f
->exts
, res
);
351 static void flow_perturbation(struct timer_list
*t
)
353 struct flow_filter
*f
= from_timer(f
, t
, perturb_timer
);
355 get_random_bytes(&f
->hashrnd
, 4);
356 if (f
->perturb_period
)
357 mod_timer(&f
->perturb_timer
, jiffies
+ f
->perturb_period
);
360 static const struct nla_policy flow_policy
[TCA_FLOW_MAX
+ 1] = {
361 [TCA_FLOW_KEYS
] = { .type
= NLA_U32
},
362 [TCA_FLOW_MODE
] = { .type
= NLA_U32
},
363 [TCA_FLOW_BASECLASS
] = { .type
= NLA_U32
},
364 [TCA_FLOW_RSHIFT
] = { .type
= NLA_U32
},
365 [TCA_FLOW_ADDEND
] = { .type
= NLA_U32
},
366 [TCA_FLOW_MASK
] = { .type
= NLA_U32
},
367 [TCA_FLOW_XOR
] = { .type
= NLA_U32
},
368 [TCA_FLOW_DIVISOR
] = { .type
= NLA_U32
},
369 [TCA_FLOW_ACT
] = { .type
= NLA_NESTED
},
370 [TCA_FLOW_POLICE
] = { .type
= NLA_NESTED
},
371 [TCA_FLOW_EMATCHES
] = { .type
= NLA_NESTED
},
372 [TCA_FLOW_PERTURB
] = { .type
= NLA_U32
},
375 static void __flow_destroy_filter(struct flow_filter
*f
)
377 del_timer_sync(&f
->perturb_timer
);
378 tcf_exts_destroy(&f
->exts
);
379 tcf_em_tree_destroy(&f
->ematches
);
380 tcf_exts_put_net(&f
->exts
);
384 static void flow_destroy_filter_work(struct work_struct
*work
)
386 struct flow_filter
*f
= container_of(work
, struct flow_filter
, work
);
389 __flow_destroy_filter(f
);
393 static void flow_destroy_filter(struct rcu_head
*head
)
395 struct flow_filter
*f
= container_of(head
, struct flow_filter
, rcu
);
397 INIT_WORK(&f
->work
, flow_destroy_filter_work
);
398 tcf_queue_work(&f
->work
);
401 static int flow_change(struct net
*net
, struct sk_buff
*in_skb
,
402 struct tcf_proto
*tp
, unsigned long base
,
403 u32 handle
, struct nlattr
**tca
,
404 void **arg
, bool ovr
, struct netlink_ext_ack
*extack
)
406 struct flow_head
*head
= rtnl_dereference(tp
->root
);
407 struct flow_filter
*fold
, *fnew
;
408 struct nlattr
*opt
= tca
[TCA_OPTIONS
];
409 struct nlattr
*tb
[TCA_FLOW_MAX
+ 1];
410 unsigned int nkeys
= 0;
411 unsigned int perturb_period
= 0;
420 err
= nla_parse_nested(tb
, TCA_FLOW_MAX
, opt
, flow_policy
, NULL
);
424 if (tb
[TCA_FLOW_BASECLASS
]) {
425 baseclass
= nla_get_u32(tb
[TCA_FLOW_BASECLASS
]);
426 if (TC_H_MIN(baseclass
) == 0)
430 if (tb
[TCA_FLOW_KEYS
]) {
431 keymask
= nla_get_u32(tb
[TCA_FLOW_KEYS
]);
433 nkeys
= hweight32(keymask
);
437 if (fls(keymask
) - 1 > FLOW_KEY_MAX
)
440 if ((keymask
& (FLOW_KEY_SKUID
|FLOW_KEY_SKGID
)) &&
441 sk_user_ns(NETLINK_CB(in_skb
).sk
) != &init_user_ns
)
445 fnew
= kzalloc(sizeof(*fnew
), GFP_KERNEL
);
449 err
= tcf_em_tree_validate(tp
, tb
[TCA_FLOW_EMATCHES
], &fnew
->ematches
);
453 err
= tcf_exts_init(&fnew
->exts
, TCA_FLOW_ACT
, TCA_FLOW_POLICE
);
457 err
= tcf_exts_validate(net
, tp
, tb
, tca
[TCA_RATE
], &fnew
->exts
, ovr
,
465 if (fold
->handle
!= handle
&& handle
)
468 /* Copy fold into fnew */
470 fnew
->handle
= fold
->handle
;
471 fnew
->nkeys
= fold
->nkeys
;
472 fnew
->keymask
= fold
->keymask
;
473 fnew
->mode
= fold
->mode
;
474 fnew
->mask
= fold
->mask
;
475 fnew
->xor = fold
->xor;
476 fnew
->rshift
= fold
->rshift
;
477 fnew
->addend
= fold
->addend
;
478 fnew
->divisor
= fold
->divisor
;
479 fnew
->baseclass
= fold
->baseclass
;
480 fnew
->hashrnd
= fold
->hashrnd
;
483 if (tb
[TCA_FLOW_MODE
])
484 mode
= nla_get_u32(tb
[TCA_FLOW_MODE
]);
485 if (mode
!= FLOW_MODE_HASH
&& nkeys
> 1)
488 if (mode
== FLOW_MODE_HASH
)
489 perturb_period
= fold
->perturb_period
;
490 if (tb
[TCA_FLOW_PERTURB
]) {
491 if (mode
!= FLOW_MODE_HASH
)
493 perturb_period
= nla_get_u32(tb
[TCA_FLOW_PERTURB
]) * HZ
;
499 if (!tb
[TCA_FLOW_KEYS
])
502 mode
= FLOW_MODE_MAP
;
503 if (tb
[TCA_FLOW_MODE
])
504 mode
= nla_get_u32(tb
[TCA_FLOW_MODE
]);
505 if (mode
!= FLOW_MODE_HASH
&& nkeys
> 1)
508 if (tb
[TCA_FLOW_PERTURB
]) {
509 if (mode
!= FLOW_MODE_HASH
)
511 perturb_period
= nla_get_u32(tb
[TCA_FLOW_PERTURB
]) * HZ
;
514 if (TC_H_MAJ(baseclass
) == 0) {
515 struct Qdisc
*q
= tcf_block_q(tp
->chain
->block
);
517 baseclass
= TC_H_MAKE(q
->handle
, baseclass
);
519 if (TC_H_MIN(baseclass
) == 0)
520 baseclass
= TC_H_MAKE(baseclass
, 1);
522 fnew
->handle
= handle
;
525 get_random_bytes(&fnew
->hashrnd
, 4);
528 timer_setup(&fnew
->perturb_timer
, flow_perturbation
, TIMER_DEFERRABLE
);
530 tcf_block_netif_keep_dst(tp
->chain
->block
);
532 if (tb
[TCA_FLOW_KEYS
]) {
533 fnew
->keymask
= keymask
;
539 if (tb
[TCA_FLOW_MASK
])
540 fnew
->mask
= nla_get_u32(tb
[TCA_FLOW_MASK
]);
541 if (tb
[TCA_FLOW_XOR
])
542 fnew
->xor = nla_get_u32(tb
[TCA_FLOW_XOR
]);
543 if (tb
[TCA_FLOW_RSHIFT
])
544 fnew
->rshift
= nla_get_u32(tb
[TCA_FLOW_RSHIFT
]);
545 if (tb
[TCA_FLOW_ADDEND
])
546 fnew
->addend
= nla_get_u32(tb
[TCA_FLOW_ADDEND
]);
548 if (tb
[TCA_FLOW_DIVISOR
])
549 fnew
->divisor
= nla_get_u32(tb
[TCA_FLOW_DIVISOR
]);
551 fnew
->baseclass
= baseclass
;
553 fnew
->perturb_period
= perturb_period
;
555 mod_timer(&fnew
->perturb_timer
, jiffies
+ perturb_period
);
558 list_add_tail_rcu(&fnew
->list
, &head
->filters
);
560 list_replace_rcu(&fold
->list
, &fnew
->list
);
565 tcf_exts_get_net(&fold
->exts
);
566 call_rcu(&fold
->rcu
, flow_destroy_filter
);
571 tcf_exts_destroy(&fnew
->exts
);
572 tcf_em_tree_destroy(&fnew
->ematches
);
578 static int flow_delete(struct tcf_proto
*tp
, void *arg
, bool *last
,
579 struct netlink_ext_ack
*extack
)
581 struct flow_head
*head
= rtnl_dereference(tp
->root
);
582 struct flow_filter
*f
= arg
;
584 list_del_rcu(&f
->list
);
585 tcf_exts_get_net(&f
->exts
);
586 call_rcu(&f
->rcu
, flow_destroy_filter
);
587 *last
= list_empty(&head
->filters
);
591 static int flow_init(struct tcf_proto
*tp
)
593 struct flow_head
*head
;
595 head
= kzalloc(sizeof(*head
), GFP_KERNEL
);
598 INIT_LIST_HEAD(&head
->filters
);
599 rcu_assign_pointer(tp
->root
, head
);
603 static void flow_destroy(struct tcf_proto
*tp
, struct netlink_ext_ack
*extack
)
605 struct flow_head
*head
= rtnl_dereference(tp
->root
);
606 struct flow_filter
*f
, *next
;
608 list_for_each_entry_safe(f
, next
, &head
->filters
, list
) {
609 list_del_rcu(&f
->list
);
610 if (tcf_exts_get_net(&f
->exts
))
611 call_rcu(&f
->rcu
, flow_destroy_filter
);
613 __flow_destroy_filter(f
);
615 kfree_rcu(head
, rcu
);
618 static void *flow_get(struct tcf_proto
*tp
, u32 handle
)
620 struct flow_head
*head
= rtnl_dereference(tp
->root
);
621 struct flow_filter
*f
;
623 list_for_each_entry(f
, &head
->filters
, list
)
624 if (f
->handle
== handle
)
629 static int flow_dump(struct net
*net
, struct tcf_proto
*tp
, void *fh
,
630 struct sk_buff
*skb
, struct tcmsg
*t
)
632 struct flow_filter
*f
= fh
;
638 t
->tcm_handle
= f
->handle
;
640 nest
= nla_nest_start(skb
, TCA_OPTIONS
);
642 goto nla_put_failure
;
644 if (nla_put_u32(skb
, TCA_FLOW_KEYS
, f
->keymask
) ||
645 nla_put_u32(skb
, TCA_FLOW_MODE
, f
->mode
))
646 goto nla_put_failure
;
648 if (f
->mask
!= ~0 || f
->xor != 0) {
649 if (nla_put_u32(skb
, TCA_FLOW_MASK
, f
->mask
) ||
650 nla_put_u32(skb
, TCA_FLOW_XOR
, f
->xor))
651 goto nla_put_failure
;
654 nla_put_u32(skb
, TCA_FLOW_RSHIFT
, f
->rshift
))
655 goto nla_put_failure
;
657 nla_put_u32(skb
, TCA_FLOW_ADDEND
, f
->addend
))
658 goto nla_put_failure
;
661 nla_put_u32(skb
, TCA_FLOW_DIVISOR
, f
->divisor
))
662 goto nla_put_failure
;
664 nla_put_u32(skb
, TCA_FLOW_BASECLASS
, f
->baseclass
))
665 goto nla_put_failure
;
667 if (f
->perturb_period
&&
668 nla_put_u32(skb
, TCA_FLOW_PERTURB
, f
->perturb_period
/ HZ
))
669 goto nla_put_failure
;
671 if (tcf_exts_dump(skb
, &f
->exts
) < 0)
672 goto nla_put_failure
;
673 #ifdef CONFIG_NET_EMATCH
674 if (f
->ematches
.hdr
.nmatches
&&
675 tcf_em_tree_dump(skb
, &f
->ematches
, TCA_FLOW_EMATCHES
) < 0)
676 goto nla_put_failure
;
678 nla_nest_end(skb
, nest
);
680 if (tcf_exts_dump_stats(skb
, &f
->exts
) < 0)
681 goto nla_put_failure
;
686 nla_nest_cancel(skb
, nest
);
690 static void flow_walk(struct tcf_proto
*tp
, struct tcf_walker
*arg
)
692 struct flow_head
*head
= rtnl_dereference(tp
->root
);
693 struct flow_filter
*f
;
695 list_for_each_entry(f
, &head
->filters
, list
) {
696 if (arg
->count
< arg
->skip
)
698 if (arg
->fn(tp
, f
, arg
) < 0) {
707 static struct tcf_proto_ops cls_flow_ops __read_mostly
= {
709 .classify
= flow_classify
,
711 .destroy
= flow_destroy
,
712 .change
= flow_change
,
713 .delete = flow_delete
,
717 .owner
= THIS_MODULE
,
720 static int __init
cls_flow_init(void)
722 return register_tcf_proto_ops(&cls_flow_ops
);
725 static void __exit
cls_flow_exit(void)
727 unregister_tcf_proto_ops(&cls_flow_ops
);
730 module_init(cls_flow_init
);
731 module_exit(cls_flow_exit
);
733 MODULE_LICENSE("GPL");
734 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
735 MODULE_DESCRIPTION("TC flow classifier");