2 * net/sched/cls_api.c Packet classifier API.
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 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
17 #include <linux/module.h>
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/skbuff.h>
23 #include <linux/init.h>
24 #include <linux/kmod.h>
25 #include <linux/netlink.h>
26 #include <linux/err.h>
27 #include <net/net_namespace.h>
29 #include <net/netlink.h>
30 #include <net/pkt_sched.h>
31 #include <net/pkt_cls.h>
33 /* The list of all installed classifier types */
35 static struct tcf_proto_ops *tcf_proto_base __read_mostly;
37 /* Protects list of registered TC modules. It is pure SMP lock. */
38 static DEFINE_RWLOCK(cls_mod_lock);
40 /* Find classifier type by string name */
42 static struct tcf_proto_ops *tcf_proto_lookup_ops(struct nlattr *kind)
44 struct tcf_proto_ops *t = NULL;
47 read_lock(&cls_mod_lock);
48 for (t = tcf_proto_base; t; t = t->next) {
49 if (nla_strcmp(kind, t->kind) == 0) {
50 if (!try_module_get(t->owner))
55 read_unlock(&cls_mod_lock);
60 /* Register(unregister) new classifier type */
62 int register_tcf_proto_ops(struct tcf_proto_ops *ops)
64 struct tcf_proto_ops *t, **tp;
67 write_lock(&cls_mod_lock);
68 for (tp = &tcf_proto_base; (t = *tp) != NULL; tp = &t->next)
69 if (!strcmp(ops->kind, t->kind))
76 write_unlock(&cls_mod_lock);
79 EXPORT_SYMBOL(register_tcf_proto_ops);
81 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
83 struct tcf_proto_ops *t, **tp;
86 write_lock(&cls_mod_lock);
87 for (tp = &tcf_proto_base; (t=*tp) != NULL; tp = &t->next)
96 write_unlock(&cls_mod_lock);
99 EXPORT_SYMBOL(unregister_tcf_proto_ops);
101 static int tfilter_notify(struct sk_buff *oskb, struct nlmsghdr *n,
102 struct tcf_proto *tp, unsigned long fh, int event);
105 /* Select new prio value from the range, managed by kernel. */
107 static inline u32 tcf_auto_prio(struct tcf_proto *tp)
109 u32 first = TC_H_MAKE(0xC0000000U, 0U);
117 /* Add/change/delete/get a filter node */
119 static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
121 struct net *net = sock_net(skb->sk);
122 struct nlattr *tca[TCA_MAX + 1];
123 spinlock_t *root_lock;
129 struct net_device *dev;
131 struct tcf_proto **back, **chain;
132 struct tcf_proto *tp;
133 struct tcf_proto_ops *tp_ops;
134 const struct Qdisc_class_ops *cops;
139 if (net != &init_net)
144 protocol = TC_H_MIN(t->tcm_info);
145 prio = TC_H_MAJ(t->tcm_info);
147 parent = t->tcm_parent;
151 /* If no priority is given, user wants we allocated it. */
152 if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
154 prio = TC_H_MAKE(0x80000000U, 0U);
157 /* Find head of filter chain. */
160 dev = __dev_get_by_index(&init_net, t->tcm_ifindex);
164 err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
170 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, 0);
171 q = dev_queue->qdisc_sleeping;
174 q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
179 /* Is it classful? */
180 if ((cops = q->ops->cl_ops) == NULL)
183 /* Do we search for filter, attached to class? */
184 if (TC_H_MIN(parent)) {
185 cl = cops->get(q, parent);
190 /* And the last stroke */
191 chain = cops->tcf_chain(q, cl);
196 /* Check the chain for existence of proto-tcf with this priority */
197 for (back = chain; (tp=*back) != NULL; back = &tp->next) {
198 if (tp->prio >= prio) {
199 if (tp->prio == prio) {
200 if (!nprio || (tp->protocol != protocol && protocol))
208 root_lock = qdisc_root_sleeping_lock(q);
211 /* Proto-tcf does not exist, create new one */
213 if (tca[TCA_KIND] == NULL || !protocol)
217 if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
221 /* Create new proto tcf */
224 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
228 tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
229 if (tp_ops == NULL) {
230 #ifdef CONFIG_MODULES
231 struct nlattr *kind = tca[TCA_KIND];
235 nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
237 request_module("cls_%s", name);
239 tp_ops = tcf_proto_lookup_ops(kind);
240 /* We dropped the RTNL semaphore in order to
241 * perform the module load. So, even if we
242 * succeeded in loading the module we have to
243 * replay the request. We indicate this using
246 if (tp_ops != NULL) {
247 module_put(tp_ops->owner);
256 tp->protocol = protocol;
257 tp->prio = nprio ? : tcf_auto_prio(*back);
259 tp->classify = tp_ops->classify;
260 tp->classid = parent;
262 err = tp_ops->init(tp);
264 module_put(tp_ops->owner);
269 spin_lock_bh(root_lock);
272 spin_unlock_bh(root_lock);
274 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
277 fh = tp->ops->get(tp, t->tcm_handle);
280 if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
281 spin_lock_bh(root_lock);
283 spin_unlock_bh(root_lock);
285 tfilter_notify(skb, n, tp, fh, RTM_DELTFILTER);
292 if (n->nlmsg_type != RTM_NEWTFILTER ||
293 !(n->nlmsg_flags & NLM_F_CREATE))
296 switch (n->nlmsg_type) {
299 if (n->nlmsg_flags & NLM_F_EXCL)
303 err = tp->ops->delete(tp, fh);
305 tfilter_notify(skb, n, tp, fh, RTM_DELTFILTER);
308 err = tfilter_notify(skb, n, tp, fh, RTM_NEWTFILTER);
316 err = tp->ops->change(tp, cl, t->tcm_handle, tca, &fh);
318 tfilter_notify(skb, n, tp, fh, RTM_NEWTFILTER);
324 /* Replay the request. */
329 static int tcf_fill_node(struct sk_buff *skb, struct tcf_proto *tp,
330 unsigned long fh, u32 pid, u32 seq, u16 flags, int event)
333 struct nlmsghdr *nlh;
334 unsigned char *b = skb_tail_pointer(skb);
336 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
337 tcm = NLMSG_DATA(nlh);
338 tcm->tcm_family = AF_UNSPEC;
341 tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
342 tcm->tcm_parent = tp->classid;
343 tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
344 NLA_PUT_STRING(skb, TCA_KIND, tp->ops->kind);
345 tcm->tcm_handle = fh;
346 if (RTM_DELTFILTER != event) {
348 if (tp->ops->dump && tp->ops->dump(tp, fh, skb, tcm) < 0)
349 goto nla_put_failure;
351 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
360 static int tfilter_notify(struct sk_buff *oskb, struct nlmsghdr *n,
361 struct tcf_proto *tp, unsigned long fh, int event)
364 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
366 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
370 if (tcf_fill_node(skb, tp, fh, pid, n->nlmsg_seq, 0, event) <= 0) {
375 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC,
376 n->nlmsg_flags & NLM_F_ECHO);
379 struct tcf_dump_args {
382 struct netlink_callback *cb;
385 static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
386 struct tcf_walker *arg)
388 struct tcf_dump_args *a = (void *)arg;
390 return tcf_fill_node(a->skb, tp, n, NETLINK_CB(a->cb->skb).pid,
391 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER);
394 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
396 struct net *net = sock_net(skb->sk);
397 struct netdev_queue *dev_queue;
400 struct net_device *dev;
402 struct tcf_proto *tp, **chain;
403 struct tcmsg *tcm = (struct tcmsg *)NLMSG_DATA(cb->nlh);
404 unsigned long cl = 0;
405 const struct Qdisc_class_ops *cops;
406 struct tcf_dump_args arg;
408 if (net != &init_net)
411 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
413 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
416 dev_queue = netdev_get_tx_queue(dev, 0);
417 if (!tcm->tcm_parent)
418 q = dev_queue->qdisc_sleeping;
420 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
423 if ((cops = q->ops->cl_ops) == NULL)
425 if (TC_H_MIN(tcm->tcm_parent)) {
426 cl = cops->get(q, tcm->tcm_parent);
430 chain = cops->tcf_chain(q, cl);
436 for (tp=*chain, t=0; tp; tp = tp->next, t++) {
437 if (t < s_t) continue;
438 if (TC_H_MAJ(tcm->tcm_info) &&
439 TC_H_MAJ(tcm->tcm_info) != tp->prio)
441 if (TC_H_MIN(tcm->tcm_info) &&
442 TC_H_MIN(tcm->tcm_info) != tp->protocol)
445 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
446 if (cb->args[1] == 0) {
447 if (tcf_fill_node(skb, tp, 0, NETLINK_CB(cb->skb).pid,
448 cb->nlh->nlmsg_seq, NLM_F_MULTI,
449 RTM_NEWTFILTER) <= 0)
454 if (tp->ops->walk == NULL)
456 arg.w.fn = tcf_node_dump;
460 arg.w.skip = cb->args[1]-1;
462 tp->ops->walk(tp, &arg.w);
463 cb->args[1] = arg.w.count+1;
478 void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts)
480 #ifdef CONFIG_NET_CLS_ACT
482 tcf_action_destroy(exts->action, TCA_ACT_UNBIND);
487 EXPORT_SYMBOL(tcf_exts_destroy);
489 int tcf_exts_validate(struct tcf_proto *tp, struct nlattr **tb,
490 struct nlattr *rate_tlv, struct tcf_exts *exts,
491 const struct tcf_ext_map *map)
493 memset(exts, 0, sizeof(*exts));
495 #ifdef CONFIG_NET_CLS_ACT
497 struct tc_action *act;
499 if (map->police && tb[map->police]) {
500 act = tcf_action_init_1(tb[map->police], rate_tlv,
501 "police", TCA_ACT_NOREPLACE,
506 act->type = TCA_OLD_COMPAT;
508 } else if (map->action && tb[map->action]) {
509 act = tcf_action_init(tb[map->action], rate_tlv, NULL,
510 TCA_ACT_NOREPLACE, TCA_ACT_BIND);
518 if ((map->action && tb[map->action]) ||
519 (map->police && tb[map->police]))
525 EXPORT_SYMBOL(tcf_exts_validate);
527 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
528 struct tcf_exts *src)
530 #ifdef CONFIG_NET_CLS_ACT
532 struct tc_action *act;
535 dst->action = src->action;
538 tcf_action_destroy(act, TCA_ACT_UNBIND);
542 EXPORT_SYMBOL(tcf_exts_change);
544 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
545 const struct tcf_ext_map *map)
547 #ifdef CONFIG_NET_CLS_ACT
548 if (map->action && exts->action) {
550 * again for backward compatible mode - we want
551 * to work with both old and new modes of entering
552 * tc data even if iproute2 was newer - jhs
556 if (exts->action->type != TCA_OLD_COMPAT) {
557 nest = nla_nest_start(skb, map->action);
559 goto nla_put_failure;
560 if (tcf_action_dump(skb, exts->action, 0, 0) < 0)
561 goto nla_put_failure;
562 nla_nest_end(skb, nest);
563 } else if (map->police) {
564 nest = nla_nest_start(skb, map->police);
566 goto nla_put_failure;
567 if (tcf_action_dump_old(skb, exts->action, 0, 0) < 0)
568 goto nla_put_failure;
569 nla_nest_end(skb, nest);
574 nla_put_failure: __attribute__ ((unused))
577 EXPORT_SYMBOL(tcf_exts_dump);
580 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
581 const struct tcf_ext_map *map)
583 #ifdef CONFIG_NET_CLS_ACT
585 if (tcf_action_copy_stats(skb, exts->action, 1) < 0)
586 goto nla_put_failure;
589 nla_put_failure: __attribute__ ((unused))
592 EXPORT_SYMBOL(tcf_exts_dump_stats);
594 static int __init tc_filter_init(void)
596 rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL);
597 rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL);
598 rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
604 subsys_initcall(tc_filter_init);