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v3.1
 
  1/*
  2 * net/sched/cls_api.c	Packet classifier API.
  3 *
  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.
  8 *
  9 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 10 *
 11 * Changes:
 12 *
 13 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
 14 *
 15 */
 16
 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 <linux/slab.h>
 
 
 
 28#include <net/net_namespace.h>
 29#include <net/sock.h>
 30#include <net/netlink.h>
 31#include <net/pkt_sched.h>
 32#include <net/pkt_cls.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 33
 34/* The list of all installed classifier types */
 35
 36static struct tcf_proto_ops *tcf_proto_base __read_mostly;
 
 37
 38/* Protects list of registered TC modules. It is pure SMP lock. */
 39static DEFINE_RWLOCK(cls_mod_lock);
 40
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 41/* Find classifier type by string name */
 42
 43static const struct tcf_proto_ops *tcf_proto_lookup_ops(struct nlattr *kind)
 44{
 45	const struct tcf_proto_ops *t = NULL;
 46
 47	if (kind) {
 48		read_lock(&cls_mod_lock);
 49		for (t = tcf_proto_base; t; t = t->next) {
 50			if (nla_strcmp(kind, t->kind) == 0) {
 51				if (!try_module_get(t->owner))
 52					t = NULL;
 53				break;
 54			}
 55		}
 56		read_unlock(&cls_mod_lock);
 57	}
 58	return t;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 59}
 60
 61/* Register(unregister) new classifier type */
 62
 63int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 64{
 65	struct tcf_proto_ops *t, **tp;
 66	int rc = -EEXIST;
 67
 68	write_lock(&cls_mod_lock);
 69	for (tp = &tcf_proto_base; (t = *tp) != NULL; tp = &t->next)
 70		if (!strcmp(ops->kind, t->kind))
 71			goto out;
 72
 73	ops->next = NULL;
 74	*tp = ops;
 75	rc = 0;
 76out:
 77	write_unlock(&cls_mod_lock);
 78	return rc;
 79}
 80EXPORT_SYMBOL(register_tcf_proto_ops);
 81
 82int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 
 
 83{
 84	struct tcf_proto_ops *t, **tp;
 85	int rc = -ENOENT;
 86
 
 
 
 
 
 
 87	write_lock(&cls_mod_lock);
 88	for (tp = &tcf_proto_base; (t = *tp) != NULL; tp = &t->next)
 89		if (t == ops)
 
 
 90			break;
 91
 92	if (!t)
 93		goto out;
 94	*tp = t->next;
 95	rc = 0;
 96out:
 97	write_unlock(&cls_mod_lock);
 98	return rc;
 
 99}
100EXPORT_SYMBOL(unregister_tcf_proto_ops);
101
102static int tfilter_notify(struct net *net, struct sk_buff *oskb,
103			  struct nlmsghdr *n, struct tcf_proto *tp,
104			  unsigned long fh, int event);
105
 
 
106
107/* Select new prio value from the range, managed by kernel. */
108
109static inline u32 tcf_auto_prio(struct tcf_proto *tp)
110{
111	u32 first = TC_H_MAKE(0xC0000000U, 0U);
112
113	if (tp)
114		first = tp->prio - 1;
115
116	return first;
117}
118
119/* Add/change/delete/get a filter node */
 
 
 
 
 
 
120
121static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
122{
123	struct net *net = sock_net(skb->sk);
124	struct nlattr *tca[TCA_MAX + 1];
125	spinlock_t *root_lock;
126	struct tcmsg *t;
127	u32 protocol;
128	u32 prio;
129	u32 nprio;
130	u32 parent;
131	struct net_device *dev;
132	struct Qdisc  *q;
133	struct tcf_proto **back, **chain;
134	struct tcf_proto *tp;
135	const struct tcf_proto_ops *tp_ops;
136	const struct Qdisc_class_ops *cops;
137	unsigned long cl;
138	unsigned long fh;
139	int err;
140	int tp_created = 0;
141
142replay:
143	t = NLMSG_DATA(n);
144	protocol = TC_H_MIN(t->tcm_info);
145	prio = TC_H_MAJ(t->tcm_info);
146	nprio = prio;
147	parent = t->tcm_parent;
148	cl = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
149
150	if (prio == 0) {
151		/* If no priority is given, user wants we allocated it. */
152		if (n->nlmsg_type != RTM_NEWTFILTER ||
153		    !(n->nlmsg_flags & NLM_F_CREATE))
154			return -ENOENT;
155		prio = TC_H_MAKE(0x80000000U, 0U);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
156	}
 
 
157
158	/* Find head of filter chain. */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
159
160	/* Find link */
161	dev = __dev_get_by_index(net, t->tcm_ifindex);
162	if (dev == NULL)
 
163		return -ENODEV;
164
165	err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
166	if (err < 0)
167		return err;
168
169	/* Find qdisc */
170	if (!parent) {
171		q = dev->qdisc;
172		parent = q->handle;
173	} else {
174		q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
175		if (q == NULL)
176			return -EINVAL;
 
 
 
 
 
 
 
 
 
 
177	}
178
179	/* Is it classful? */
180	cops = q->ops->cl_ops;
181	if (!cops)
182		return -EINVAL;
 
 
 
183
184	if (cops->tcf_chain == NULL)
185		return -EOPNOTSUPP;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
186
187	/* Do we search for filter, attached to class? */
188	if (TC_H_MIN(parent)) {
189		cl = cops->get(q, parent);
190		if (cl == 0)
 
 
 
191			return -ENOENT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
192	}
193
194	/* And the last stroke */
195	chain = cops->tcf_chain(q, cl);
196	err = -EINVAL;
197	if (chain == NULL)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
198		goto errout;
199
200	/* Check the chain for existence of proto-tcf with this priority */
201	for (back = chain; (tp = *back) != NULL; back = &tp->next) {
202		if (tp->prio >= prio) {
203			if (tp->prio == prio) {
204				if (!nprio ||
205				    (tp->protocol != protocol && protocol))
206					goto errout;
207			} else
208				tp = NULL;
209			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
210		}
211	}
 
 
212
213	root_lock = qdisc_root_sleeping_lock(q);
 
 
 
 
 
 
214
215	if (tp == NULL) {
216		/* Proto-tcf does not exist, create new one */
 
 
 
 
 
 
 
 
 
 
 
 
217
218		if (tca[TCA_KIND] == NULL || !protocol)
219			goto errout;
 
220
221		err = -ENOENT;
222		if (n->nlmsg_type != RTM_NEWTFILTER ||
223		    !(n->nlmsg_flags & NLM_F_CREATE))
224			goto errout;
225
 
 
 
226
227		/* Create new proto tcf */
 
 
228
229		err = -ENOBUFS;
230		tp = kzalloc(sizeof(*tp), GFP_KERNEL);
231		if (tp == NULL)
232			goto errout;
233		err = -ENOENT;
234		tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
235		if (tp_ops == NULL) {
236#ifdef CONFIG_MODULES
237			struct nlattr *kind = tca[TCA_KIND];
238			char name[IFNAMSIZ];
239
240			if (kind != NULL &&
241			    nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
242				rtnl_unlock();
243				request_module("cls_%s", name);
244				rtnl_lock();
245				tp_ops = tcf_proto_lookup_ops(kind);
246				/* We dropped the RTNL semaphore in order to
247				 * perform the module load.  So, even if we
248				 * succeeded in loading the module we have to
249				 * replay the request.  We indicate this using
250				 * -EAGAIN.
251				 */
252				if (tp_ops != NULL) {
253					module_put(tp_ops->owner);
254					err = -EAGAIN;
255				}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
256			}
257#endif
258			kfree(tp);
259			goto errout;
260		}
261		tp->ops = tp_ops;
262		tp->protocol = protocol;
263		tp->prio = nprio ? : TC_H_MAJ(tcf_auto_prio(*back));
264		tp->q = q;
265		tp->classify = tp_ops->classify;
266		tp->classid = parent;
267
268		err = tp_ops->init(tp);
269		if (err != 0) {
270			module_put(tp_ops->owner);
271			kfree(tp);
272			goto errout;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
273		}
 
 
274
275		tp_created = 1;
 
276
277	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
278		goto errout;
 
 
279
280	fh = tp->ops->get(tp, t->tcm_handle);
281
282	if (fh == 0) {
283		if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
284			spin_lock_bh(root_lock);
285			*back = tp->next;
286			spin_unlock_bh(root_lock);
 
 
 
 
 
 
287
288			tfilter_notify(net, skb, n, tp, fh, RTM_DELTFILTER);
289			tcf_destroy(tp);
290			err = 0;
291			goto errout;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
292		}
 
 
 
 
293
294		err = -ENOENT;
295		if (n->nlmsg_type != RTM_NEWTFILTER ||
296		    !(n->nlmsg_flags & NLM_F_CREATE))
297			goto errout;
298	} else {
299		switch (n->nlmsg_type) {
300		case RTM_NEWTFILTER:
301			err = -EEXIST;
302			if (n->nlmsg_flags & NLM_F_EXCL) {
303				if (tp_created)
304					tcf_destroy(tp);
305				goto errout;
306			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
307			break;
308		case RTM_DELTFILTER:
309			err = tp->ops->delete(tp, fh);
310			if (err == 0)
311				tfilter_notify(net, skb, n, tp, fh, RTM_DELTFILTER);
312			goto errout;
313		case RTM_GETTFILTER:
314			err = tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER);
315			goto errout;
316		default:
317			err = -EINVAL;
318			goto errout;
319		}
320	}
 
 
 
 
 
 
 
 
321
322	err = tp->ops->change(tp, cl, t->tcm_handle, tca, &fh);
323	if (err == 0) {
324		if (tp_created) {
325			spin_lock_bh(root_lock);
326			tp->next = *back;
327			*back = tp;
328			spin_unlock_bh(root_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
329		}
330		tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER);
 
 
 
 
331	} else {
332		if (tp_created)
333			tcf_destroy(tp);
334	}
335
336errout:
337	if (cl)
338		cops->put(q, cl);
339	if (err == -EAGAIN)
340		/* Replay the request. */
341		goto replay;
342	return err;
343}
344
345static int tcf_fill_node(struct sk_buff *skb, struct tcf_proto *tp,
346			 unsigned long fh, u32 pid, u32 seq, u16 flags, int event)
 
 
 
347{
348	struct tcmsg *tcm;
349	struct nlmsghdr  *nlh;
350	unsigned char *b = skb_tail_pointer(skb);
351
352	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
353	tcm = NLMSG_DATA(nlh);
 
 
354	tcm->tcm_family = AF_UNSPEC;
355	tcm->tcm__pad1 = 0;
356	tcm->tcm__pad2 = 0;
357	tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
358	tcm->tcm_parent = tp->classid;
 
 
 
 
 
359	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
360	NLA_PUT_STRING(skb, TCA_KIND, tp->ops->kind);
361	tcm->tcm_handle = fh;
362	if (RTM_DELTFILTER != event) {
 
 
363		tcm->tcm_handle = 0;
364		if (tp->ops->dump && tp->ops->dump(tp, fh, skb, tcm) < 0)
 
 
 
 
 
 
 
 
 
 
365			goto nla_put_failure;
366	}
367	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
368	return skb->len;
369
370nlmsg_failure:
371nla_put_failure:
 
372	nlmsg_trim(skb, b);
373	return -1;
374}
375
376static int tfilter_notify(struct net *net, struct sk_buff *oskb,
377			  struct nlmsghdr *n, struct tcf_proto *tp,
378			  unsigned long fh, int event)
 
 
379{
380	struct sk_buff *skb;
381	u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
 
382
383	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
384	if (!skb)
385		return -ENOBUFS;
386
387	if (tcf_fill_node(skb, tp, fh, pid, n->nlmsg_seq, 0, event) <= 0) {
 
 
388		kfree_skb(skb);
389		return -EINVAL;
390	}
391
392	return rtnetlink_send(skb, net, pid, RTNLGRP_TC,
393			      n->nlmsg_flags & NLM_F_ECHO);
 
 
 
 
394}
395
396struct tcf_dump_args {
397	struct tcf_walker w;
 
 
 
 
398	struct sk_buff *skb;
399	struct netlink_callback *cb;
400};
 
 
 
 
401
402static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
403			 struct tcf_walker *arg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
404{
405	struct tcf_dump_args *a = (void *)arg;
406
407	return tcf_fill_node(a->skb, tp, n, NETLINK_CB(a->cb->skb).pid,
408			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER);
 
 
409}
410
411/* called with RTNL */
412static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
 
 
 
 
 
 
 
 
 
 
 
413{
414	struct net *net = sock_net(skb->sk);
415	int t;
416	int s_t;
417	struct net_device *dev;
 
 
 
 
 
418	struct Qdisc *q;
419	struct tcf_proto *tp, **chain;
420	struct tcmsg *tcm = (struct tcmsg *)NLMSG_DATA(cb->nlh);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
421	unsigned long cl = 0;
422	const struct Qdisc_class_ops *cops;
423	struct tcf_dump_args arg;
 
424
425	if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
426		return skb->len;
427	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
428	if (!dev)
429		return skb->len;
430
431	if (!tcm->tcm_parent)
432		q = dev->qdisc;
433	else
434		q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
435	if (!q)
436		goto out;
437	cops = q->ops->cl_ops;
438	if (!cops)
439		goto errout;
440	if (cops->tcf_chain == NULL)
441		goto errout;
442	if (TC_H_MIN(tcm->tcm_parent)) {
443		cl = cops->get(q, tcm->tcm_parent);
444		if (cl == 0)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
445			goto errout;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
446	}
447	chain = cops->tcf_chain(q, cl);
448	if (chain == NULL)
 
449		goto errout;
450
451	s_t = cb->args[0];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
452
453	for (tp = *chain, t = 0; tp; tp = tp->next, t++) {
454		if (t < s_t)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
455			continue;
456		if (TC_H_MAJ(tcm->tcm_info) &&
457		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
458			continue;
459		if (TC_H_MIN(tcm->tcm_info) &&
460		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
461			continue;
462		if (t > s_t)
463			memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
 
464		if (cb->args[1] == 0) {
465			if (tcf_fill_node(skb, tp, 0, NETLINK_CB(cb->skb).pid,
 
466					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
467					  RTM_NEWTFILTER) <= 0)
468				break;
469
470			cb->args[1] = 1;
471		}
472		if (tp->ops->walk == NULL)
473			continue;
474		arg.w.fn = tcf_node_dump;
475		arg.skb = skb;
476		arg.cb = cb;
 
 
 
477		arg.w.stop = 0;
478		arg.w.skip = cb->args[1] - 1;
479		arg.w.count = 0;
480		tp->ops->walk(tp, &arg.w);
 
 
 
481		cb->args[1] = arg.w.count + 1;
482		if (arg.w.stop)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
483			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
484	}
485
486	cb->args[0] = t;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
487
488errout:
489	if (cl)
490		cops->put(q, cl);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
491out:
 
 
 
492	return skb->len;
493}
494
495void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts)
496{
497#ifdef CONFIG_NET_CLS_ACT
498	if (exts->action) {
499		tcf_action_destroy(exts->action, TCA_ACT_UNBIND);
500		exts->action = NULL;
501	}
 
502#endif
503}
504EXPORT_SYMBOL(tcf_exts_destroy);
505
506int tcf_exts_validate(struct tcf_proto *tp, struct nlattr **tb,
507		  struct nlattr *rate_tlv, struct tcf_exts *exts,
508		  const struct tcf_ext_map *map)
509{
510	memset(exts, 0, sizeof(*exts));
511
512#ifdef CONFIG_NET_CLS_ACT
513	{
 
514		struct tc_action *act;
 
515
516		if (map->police && tb[map->police]) {
517			act = tcf_action_init_1(tb[map->police], rate_tlv,
518						"police", TCA_ACT_NOREPLACE,
519						TCA_ACT_BIND);
520			if (IS_ERR(act))
521				return PTR_ERR(act);
522
523			act->type = TCA_OLD_COMPAT;
524			exts->action = act;
525		} else if (map->action && tb[map->action]) {
526			act = tcf_action_init(tb[map->action], rate_tlv, NULL,
527					      TCA_ACT_NOREPLACE, TCA_ACT_BIND);
 
 
 
 
 
528			if (IS_ERR(act))
529				return PTR_ERR(act);
530
531			exts->action = act;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
532		}
533	}
534#else
535	if ((map->action && tb[map->action]) ||
536	    (map->police && tb[map->police]))
 
537		return -EOPNOTSUPP;
 
538#endif
539
540	return 0;
541}
 
 
 
 
 
 
 
 
 
542EXPORT_SYMBOL(tcf_exts_validate);
543
544void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
545		     struct tcf_exts *src)
546{
547#ifdef CONFIG_NET_CLS_ACT
548	if (src->action) {
549		struct tc_action *act;
550		tcf_tree_lock(tp);
551		act = dst->action;
552		dst->action = src->action;
553		tcf_tree_unlock(tp);
554		if (act)
555			tcf_action_destroy(act, TCA_ACT_UNBIND);
556	}
557#endif
558}
559EXPORT_SYMBOL(tcf_exts_change);
560
561int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
562		  const struct tcf_ext_map *map)
 
 
 
 
 
 
 
 
 
563{
564#ifdef CONFIG_NET_CLS_ACT
565	if (map->action && exts->action) {
 
 
566		/*
567		 * again for backward compatible mode - we want
568		 * to work with both old and new modes of entering
569		 * tc data even if iproute2  was newer - jhs
570		 */
571		struct nlattr *nest;
572
573		if (exts->action->type != TCA_OLD_COMPAT) {
574			nest = nla_nest_start(skb, map->action);
575			if (nest == NULL)
576				goto nla_put_failure;
577			if (tcf_action_dump(skb, exts->action, 0, 0) < 0)
 
 
578				goto nla_put_failure;
579			nla_nest_end(skb, nest);
580		} else if (map->police) {
581			nest = nla_nest_start(skb, map->police);
582			if (nest == NULL)
 
583				goto nla_put_failure;
584			if (tcf_action_dump_old(skb, exts->action, 0, 0) < 0)
585				goto nla_put_failure;
586			nla_nest_end(skb, nest);
587		}
588	}
589#endif
590	return 0;
591nla_put_failure: __attribute__ ((unused))
 
 
592	return -1;
 
 
 
593}
594EXPORT_SYMBOL(tcf_exts_dump);
595
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
596
597int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
598			const struct tcf_ext_map *map)
 
 
 
 
 
 
 
 
599{
600#ifdef CONFIG_NET_CLS_ACT
601	if (exts->action)
602		if (tcf_action_copy_stats(skb, exts->action, 1) < 0)
603			goto nla_put_failure;
604#endif
605	return 0;
606nla_put_failure: __attribute__ ((unused))
607	return -1;
608}
609EXPORT_SYMBOL(tcf_exts_dump_stats);
610
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
611static int __init tc_filter_init(void)
612{
613	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, NULL);
614	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, NULL);
615	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
616		      tc_dump_tfilter, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
617
618	return 0;
 
 
 
 
619}
620
621subsys_initcall(tc_filter_init);
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * net/sched/cls_api.c	Packet classifier API.
   4 *
 
 
 
 
 
   5 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   6 *
   7 * Changes:
   8 *
   9 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
 
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/types.h>
  14#include <linux/kernel.h>
  15#include <linux/string.h>
  16#include <linux/errno.h>
  17#include <linux/err.h>
  18#include <linux/skbuff.h>
  19#include <linux/init.h>
  20#include <linux/kmod.h>
 
 
  21#include <linux/slab.h>
  22#include <linux/idr.h>
  23#include <linux/jhash.h>
  24#include <linux/rculist.h>
  25#include <net/net_namespace.h>
  26#include <net/sock.h>
  27#include <net/netlink.h>
  28#include <net/pkt_sched.h>
  29#include <net/pkt_cls.h>
  30#include <net/tc_act/tc_pedit.h>
  31#include <net/tc_act/tc_mirred.h>
  32#include <net/tc_act/tc_vlan.h>
  33#include <net/tc_act/tc_tunnel_key.h>
  34#include <net/tc_act/tc_csum.h>
  35#include <net/tc_act/tc_gact.h>
  36#include <net/tc_act/tc_police.h>
  37#include <net/tc_act/tc_sample.h>
  38#include <net/tc_act/tc_skbedit.h>
  39#include <net/tc_act/tc_ct.h>
  40#include <net/tc_act/tc_mpls.h>
  41#include <net/tc_act/tc_gate.h>
  42#include <net/flow_offload.h>
  43#include <net/tc_wrapper.h>
  44
  45extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
  46
  47/* The list of all installed classifier types */
  48static LIST_HEAD(tcf_proto_base);
  49
  50/* Protects list of registered TC modules. It is pure SMP lock. */
  51static DEFINE_RWLOCK(cls_mod_lock);
  52
  53#ifdef CONFIG_NET_CLS_ACT
  54DEFINE_STATIC_KEY_FALSE(tc_skb_ext_tc);
  55EXPORT_SYMBOL(tc_skb_ext_tc);
  56
  57void tc_skb_ext_tc_enable(void)
  58{
  59	static_branch_inc(&tc_skb_ext_tc);
  60}
  61EXPORT_SYMBOL(tc_skb_ext_tc_enable);
  62
  63void tc_skb_ext_tc_disable(void)
  64{
  65	static_branch_dec(&tc_skb_ext_tc);
  66}
  67EXPORT_SYMBOL(tc_skb_ext_tc_disable);
  68#endif
  69
  70static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
  71{
  72	return jhash_3words(tp->chain->index, tp->prio,
  73			    (__force __u32)tp->protocol, 0);
  74}
  75
  76static void tcf_proto_signal_destroying(struct tcf_chain *chain,
  77					struct tcf_proto *tp)
  78{
  79	struct tcf_block *block = chain->block;
  80
  81	mutex_lock(&block->proto_destroy_lock);
  82	hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
  83		     destroy_obj_hashfn(tp));
  84	mutex_unlock(&block->proto_destroy_lock);
  85}
  86
  87static bool tcf_proto_cmp(const struct tcf_proto *tp1,
  88			  const struct tcf_proto *tp2)
  89{
  90	return tp1->chain->index == tp2->chain->index &&
  91	       tp1->prio == tp2->prio &&
  92	       tp1->protocol == tp2->protocol;
  93}
  94
  95static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
  96					struct tcf_proto *tp)
  97{
  98	u32 hash = destroy_obj_hashfn(tp);
  99	struct tcf_proto *iter;
 100	bool found = false;
 101
 102	rcu_read_lock();
 103	hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
 104				   destroy_ht_node, hash) {
 105		if (tcf_proto_cmp(tp, iter)) {
 106			found = true;
 107			break;
 108		}
 109	}
 110	rcu_read_unlock();
 111
 112	return found;
 113}
 114
 115static void
 116tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
 117{
 118	struct tcf_block *block = chain->block;
 119
 120	mutex_lock(&block->proto_destroy_lock);
 121	if (hash_hashed(&tp->destroy_ht_node))
 122		hash_del_rcu(&tp->destroy_ht_node);
 123	mutex_unlock(&block->proto_destroy_lock);
 124}
 125
 126/* Find classifier type by string name */
 127
 128static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
 129{
 130	const struct tcf_proto_ops *t, *res = NULL;
 131
 132	if (kind) {
 133		read_lock(&cls_mod_lock);
 134		list_for_each_entry(t, &tcf_proto_base, head) {
 135			if (strcmp(kind, t->kind) == 0) {
 136				if (try_module_get(t->owner))
 137					res = t;
 138				break;
 139			}
 140		}
 141		read_unlock(&cls_mod_lock);
 142	}
 143	return res;
 144}
 145
 146static const struct tcf_proto_ops *
 147tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
 148		     struct netlink_ext_ack *extack)
 149{
 150	const struct tcf_proto_ops *ops;
 151
 152	ops = __tcf_proto_lookup_ops(kind);
 153	if (ops)
 154		return ops;
 155#ifdef CONFIG_MODULES
 156	if (rtnl_held)
 157		rtnl_unlock();
 158	request_module("cls_%s", kind);
 159	if (rtnl_held)
 160		rtnl_lock();
 161	ops = __tcf_proto_lookup_ops(kind);
 162	/* We dropped the RTNL semaphore in order to perform
 163	 * the module load. So, even if we succeeded in loading
 164	 * the module we have to replay the request. We indicate
 165	 * this using -EAGAIN.
 166	 */
 167	if (ops) {
 168		module_put(ops->owner);
 169		return ERR_PTR(-EAGAIN);
 170	}
 171#endif
 172	NL_SET_ERR_MSG(extack, "TC classifier not found");
 173	return ERR_PTR(-ENOENT);
 174}
 175
 176/* Register(unregister) new classifier type */
 177
 178int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 179{
 180	struct tcf_proto_ops *t;
 181	int rc = -EEXIST;
 182
 183	write_lock(&cls_mod_lock);
 184	list_for_each_entry(t, &tcf_proto_base, head)
 185		if (!strcmp(ops->kind, t->kind))
 186			goto out;
 187
 188	list_add_tail(&ops->head, &tcf_proto_base);
 
 189	rc = 0;
 190out:
 191	write_unlock(&cls_mod_lock);
 192	return rc;
 193}
 194EXPORT_SYMBOL(register_tcf_proto_ops);
 195
 196static struct workqueue_struct *tc_filter_wq;
 197
 198void unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 199{
 200	struct tcf_proto_ops *t;
 201	int rc = -ENOENT;
 202
 203	/* Wait for outstanding call_rcu()s, if any, from a
 204	 * tcf_proto_ops's destroy() handler.
 205	 */
 206	rcu_barrier();
 207	flush_workqueue(tc_filter_wq);
 208
 209	write_lock(&cls_mod_lock);
 210	list_for_each_entry(t, &tcf_proto_base, head) {
 211		if (t == ops) {
 212			list_del(&t->head);
 213			rc = 0;
 214			break;
 215		}
 216	}
 
 
 
 
 217	write_unlock(&cls_mod_lock);
 218
 219	WARN(rc, "unregister tc filter kind(%s) failed %d\n", ops->kind, rc);
 220}
 221EXPORT_SYMBOL(unregister_tcf_proto_ops);
 222
 223bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
 224{
 225	INIT_RCU_WORK(rwork, func);
 226	return queue_rcu_work(tc_filter_wq, rwork);
 227}
 228EXPORT_SYMBOL(tcf_queue_work);
 229
 230/* Select new prio value from the range, managed by kernel. */
 231
 232static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 233{
 234	u32 first = TC_H_MAKE(0xC0000000U, 0U);
 235
 236	if (tp)
 237		first = tp->prio - 1;
 238
 239	return TC_H_MAJ(first);
 240}
 241
 242static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 243{
 244	if (kind)
 245		return nla_strscpy(name, kind, IFNAMSIZ) < 0;
 246	memset(name, 0, IFNAMSIZ);
 247	return false;
 248}
 249
 250static bool tcf_proto_is_unlocked(const char *kind)
 251{
 252	const struct tcf_proto_ops *ops;
 253	bool ret;
 254
 255	if (strlen(kind) == 0)
 256		return false;
 257
 258	ops = tcf_proto_lookup_ops(kind, false, NULL);
 259	/* On error return false to take rtnl lock. Proto lookup/create
 260	 * functions will perform lookup again and properly handle errors.
 261	 */
 262	if (IS_ERR(ops))
 263		return false;
 264
 265	ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
 266	module_put(ops->owner);
 267	return ret;
 268}
 269
 270static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 271					  u32 prio, struct tcf_chain *chain,
 272					  bool rtnl_held,
 273					  struct netlink_ext_ack *extack)
 274{
 
 
 
 
 
 
 
 
 
 
 
 275	struct tcf_proto *tp;
 
 
 
 
 276	int err;
 
 277
 278	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 279	if (!tp)
 280		return ERR_PTR(-ENOBUFS);
 281
 282	tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
 283	if (IS_ERR(tp->ops)) {
 284		err = PTR_ERR(tp->ops);
 285		goto errout;
 286	}
 287	tp->classify = tp->ops->classify;
 288	tp->protocol = protocol;
 289	tp->prio = prio;
 290	tp->chain = chain;
 291	spin_lock_init(&tp->lock);
 292	refcount_set(&tp->refcnt, 1);
 293
 294	err = tp->ops->init(tp);
 295	if (err) {
 296		module_put(tp->ops->owner);
 297		goto errout;
 298	}
 299	return tp;
 300
 301errout:
 302	kfree(tp);
 303	return ERR_PTR(err);
 304}
 305
 306static void tcf_proto_get(struct tcf_proto *tp)
 307{
 308	refcount_inc(&tp->refcnt);
 309}
 310
 311static void tcf_chain_put(struct tcf_chain *chain);
 312
 313static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 314			      bool sig_destroy, struct netlink_ext_ack *extack)
 315{
 316	tp->ops->destroy(tp, rtnl_held, extack);
 317	if (sig_destroy)
 318		tcf_proto_signal_destroyed(tp->chain, tp);
 319	tcf_chain_put(tp->chain);
 320	module_put(tp->ops->owner);
 321	kfree_rcu(tp, rcu);
 322}
 323
 324static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
 325			  struct netlink_ext_ack *extack)
 326{
 327	if (refcount_dec_and_test(&tp->refcnt))
 328		tcf_proto_destroy(tp, rtnl_held, true, extack);
 329}
 330
 331static bool tcf_proto_check_delete(struct tcf_proto *tp)
 332{
 333	if (tp->ops->delete_empty)
 334		return tp->ops->delete_empty(tp);
 335
 336	tp->deleting = true;
 337	return tp->deleting;
 338}
 339
 340static void tcf_proto_mark_delete(struct tcf_proto *tp)
 341{
 342	spin_lock(&tp->lock);
 343	tp->deleting = true;
 344	spin_unlock(&tp->lock);
 345}
 346
 347static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 348{
 349	bool deleting;
 350
 351	spin_lock(&tp->lock);
 352	deleting = tp->deleting;
 353	spin_unlock(&tp->lock);
 354
 355	return deleting;
 356}
 357
 358#define ASSERT_BLOCK_LOCKED(block)					\
 359	lockdep_assert_held(&(block)->lock)
 360
 361struct tcf_filter_chain_list_item {
 362	struct list_head list;
 363	tcf_chain_head_change_t *chain_head_change;
 364	void *chain_head_change_priv;
 365};
 366
 367static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 368					  u32 chain_index)
 369{
 370	struct tcf_chain *chain;
 371
 372	ASSERT_BLOCK_LOCKED(block);
 373
 374	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 375	if (!chain)
 376		return NULL;
 377	list_add_tail_rcu(&chain->list, &block->chain_list);
 378	mutex_init(&chain->filter_chain_lock);
 379	chain->block = block;
 380	chain->index = chain_index;
 381	chain->refcnt = 1;
 382	if (!chain->index)
 383		block->chain0.chain = chain;
 384	return chain;
 385}
 386
 387static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 388				       struct tcf_proto *tp_head)
 389{
 390	if (item->chain_head_change)
 391		item->chain_head_change(tp_head, item->chain_head_change_priv);
 392}
 393
 394static void tcf_chain0_head_change(struct tcf_chain *chain,
 395				   struct tcf_proto *tp_head)
 396{
 397	struct tcf_filter_chain_list_item *item;
 398	struct tcf_block *block = chain->block;
 399
 400	if (chain->index)
 401		return;
 402
 403	mutex_lock(&block->lock);
 404	list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 405		tcf_chain_head_change_item(item, tp_head);
 406	mutex_unlock(&block->lock);
 407}
 408
 409/* Returns true if block can be safely freed. */
 410
 411static bool tcf_chain_detach(struct tcf_chain *chain)
 412{
 413	struct tcf_block *block = chain->block;
 414
 415	ASSERT_BLOCK_LOCKED(block);
 416
 417	list_del_rcu(&chain->list);
 418	if (!chain->index)
 419		block->chain0.chain = NULL;
 420
 421	if (list_empty(&block->chain_list) &&
 422	    refcount_read(&block->refcnt) == 0)
 423		return true;
 424
 425	return false;
 426}
 427
 428static void tcf_block_destroy(struct tcf_block *block)
 429{
 430	mutex_destroy(&block->lock);
 431	mutex_destroy(&block->proto_destroy_lock);
 432	kfree_rcu(block, rcu);
 433}
 434
 435static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 436{
 437	struct tcf_block *block = chain->block;
 438
 439	mutex_destroy(&chain->filter_chain_lock);
 440	kfree_rcu(chain, rcu);
 441	if (free_block)
 442		tcf_block_destroy(block);
 443}
 444
 445static void tcf_chain_hold(struct tcf_chain *chain)
 446{
 447	ASSERT_BLOCK_LOCKED(chain->block);
 448
 449	++chain->refcnt;
 450}
 451
 452static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 453{
 454	ASSERT_BLOCK_LOCKED(chain->block);
 455
 456	/* In case all the references are action references, this
 457	 * chain should not be shown to the user.
 458	 */
 459	return chain->refcnt == chain->action_refcnt;
 460}
 461
 462static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 463					  u32 chain_index)
 464{
 465	struct tcf_chain *chain;
 466
 467	ASSERT_BLOCK_LOCKED(block);
 468
 469	list_for_each_entry(chain, &block->chain_list, list) {
 470		if (chain->index == chain_index)
 471			return chain;
 472	}
 473	return NULL;
 474}
 475
 476#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 477static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
 478					      u32 chain_index)
 479{
 480	struct tcf_chain *chain;
 481
 482	list_for_each_entry_rcu(chain, &block->chain_list, list) {
 483		if (chain->index == chain_index)
 484			return chain;
 485	}
 486	return NULL;
 487}
 488#endif
 489
 490static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 491			   u32 seq, u16 flags, int event, bool unicast);
 492
 493static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 494					 u32 chain_index, bool create,
 495					 bool by_act)
 496{
 497	struct tcf_chain *chain = NULL;
 498	bool is_first_reference;
 499
 500	mutex_lock(&block->lock);
 501	chain = tcf_chain_lookup(block, chain_index);
 502	if (chain) {
 503		tcf_chain_hold(chain);
 504	} else {
 505		if (!create)
 506			goto errout;
 507		chain = tcf_chain_create(block, chain_index);
 508		if (!chain)
 509			goto errout;
 510	}
 511
 512	if (by_act)
 513		++chain->action_refcnt;
 514	is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 515	mutex_unlock(&block->lock);
 516
 517	/* Send notification only in case we got the first
 518	 * non-action reference. Until then, the chain acts only as
 519	 * a placeholder for actions pointing to it and user ought
 520	 * not know about them.
 521	 */
 522	if (is_first_reference && !by_act)
 523		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 524				RTM_NEWCHAIN, false);
 525
 526	return chain;
 527
 528errout:
 529	mutex_unlock(&block->lock);
 530	return chain;
 531}
 532
 533static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 534				       bool create)
 535{
 536	return __tcf_chain_get(block, chain_index, create, false);
 537}
 538
 539struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 540{
 541	return __tcf_chain_get(block, chain_index, true, true);
 542}
 543EXPORT_SYMBOL(tcf_chain_get_by_act);
 544
 545static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 546			       void *tmplt_priv);
 547static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 548				  void *tmplt_priv, u32 chain_index,
 549				  struct tcf_block *block, struct sk_buff *oskb,
 550				  u32 seq, u16 flags, bool unicast);
 551
 552static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 553			    bool explicitly_created)
 554{
 555	struct tcf_block *block = chain->block;
 556	const struct tcf_proto_ops *tmplt_ops;
 557	bool free_block = false;
 558	unsigned int refcnt;
 559	void *tmplt_priv;
 560
 561	mutex_lock(&block->lock);
 562	if (explicitly_created) {
 563		if (!chain->explicitly_created) {
 564			mutex_unlock(&block->lock);
 565			return;
 566		}
 567		chain->explicitly_created = false;
 568	}
 569
 570	if (by_act)
 571		chain->action_refcnt--;
 572
 573	/* tc_chain_notify_delete can't be called while holding block lock.
 574	 * However, when block is unlocked chain can be changed concurrently, so
 575	 * save these to temporary variables.
 576	 */
 577	refcnt = --chain->refcnt;
 578	tmplt_ops = chain->tmplt_ops;
 579	tmplt_priv = chain->tmplt_priv;
 580
 581	/* The last dropped non-action reference will trigger notification. */
 582	if (refcnt - chain->action_refcnt == 0 && !by_act) {
 583		tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
 584				       block, NULL, 0, 0, false);
 585		/* Last reference to chain, no need to lock. */
 586		chain->flushing = false;
 587	}
 588
 589	if (refcnt == 0)
 590		free_block = tcf_chain_detach(chain);
 591	mutex_unlock(&block->lock);
 592
 593	if (refcnt == 0) {
 594		tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 595		tcf_chain_destroy(chain, free_block);
 596	}
 597}
 598
 599static void tcf_chain_put(struct tcf_chain *chain)
 600{
 601	__tcf_chain_put(chain, false, false);
 602}
 603
 604void tcf_chain_put_by_act(struct tcf_chain *chain)
 605{
 606	__tcf_chain_put(chain, true, false);
 607}
 608EXPORT_SYMBOL(tcf_chain_put_by_act);
 609
 610static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 611{
 612	__tcf_chain_put(chain, false, true);
 613}
 614
 615static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 616{
 617	struct tcf_proto *tp, *tp_next;
 618
 619	mutex_lock(&chain->filter_chain_lock);
 620	tp = tcf_chain_dereference(chain->filter_chain, chain);
 621	while (tp) {
 622		tp_next = rcu_dereference_protected(tp->next, 1);
 623		tcf_proto_signal_destroying(chain, tp);
 624		tp = tp_next;
 625	}
 626	tp = tcf_chain_dereference(chain->filter_chain, chain);
 627	RCU_INIT_POINTER(chain->filter_chain, NULL);
 628	tcf_chain0_head_change(chain, NULL);
 629	chain->flushing = true;
 630	mutex_unlock(&chain->filter_chain_lock);
 631
 632	while (tp) {
 633		tp_next = rcu_dereference_protected(tp->next, 1);
 634		tcf_proto_put(tp, rtnl_held, NULL);
 635		tp = tp_next;
 636	}
 637}
 638
 639static int tcf_block_setup(struct tcf_block *block,
 640			   struct flow_block_offload *bo);
 641
 642static void tcf_block_offload_init(struct flow_block_offload *bo,
 643				   struct net_device *dev, struct Qdisc *sch,
 644				   enum flow_block_command command,
 645				   enum flow_block_binder_type binder_type,
 646				   struct flow_block *flow_block,
 647				   bool shared, struct netlink_ext_ack *extack)
 648{
 649	bo->net = dev_net(dev);
 650	bo->command = command;
 651	bo->binder_type = binder_type;
 652	bo->block = flow_block;
 653	bo->block_shared = shared;
 654	bo->extack = extack;
 655	bo->sch = sch;
 656	bo->cb_list_head = &flow_block->cb_list;
 657	INIT_LIST_HEAD(&bo->cb_list);
 658}
 659
 660static void tcf_block_unbind(struct tcf_block *block,
 661			     struct flow_block_offload *bo);
 662
 663static void tc_block_indr_cleanup(struct flow_block_cb *block_cb)
 664{
 665	struct tcf_block *block = block_cb->indr.data;
 666	struct net_device *dev = block_cb->indr.dev;
 667	struct Qdisc *sch = block_cb->indr.sch;
 668	struct netlink_ext_ack extack = {};
 669	struct flow_block_offload bo = {};
 670
 671	tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND,
 672			       block_cb->indr.binder_type,
 673			       &block->flow_block, tcf_block_shared(block),
 674			       &extack);
 675	rtnl_lock();
 676	down_write(&block->cb_lock);
 677	list_del(&block_cb->driver_list);
 678	list_move(&block_cb->list, &bo.cb_list);
 679	tcf_block_unbind(block, &bo);
 680	up_write(&block->cb_lock);
 681	rtnl_unlock();
 682}
 683
 684static bool tcf_block_offload_in_use(struct tcf_block *block)
 685{
 686	return atomic_read(&block->offloadcnt);
 687}
 688
 689static int tcf_block_offload_cmd(struct tcf_block *block,
 690				 struct net_device *dev, struct Qdisc *sch,
 691				 struct tcf_block_ext_info *ei,
 692				 enum flow_block_command command,
 693				 struct netlink_ext_ack *extack)
 694{
 695	struct flow_block_offload bo = {};
 696
 697	tcf_block_offload_init(&bo, dev, sch, command, ei->binder_type,
 698			       &block->flow_block, tcf_block_shared(block),
 699			       extack);
 700
 701	if (dev->netdev_ops->ndo_setup_tc) {
 702		int err;
 703
 704		err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 705		if (err < 0) {
 706			if (err != -EOPNOTSUPP)
 707				NL_SET_ERR_MSG(extack, "Driver ndo_setup_tc failed");
 708			return err;
 709		}
 710
 711		return tcf_block_setup(block, &bo);
 712	}
 713
 714	flow_indr_dev_setup_offload(dev, sch, TC_SETUP_BLOCK, block, &bo,
 715				    tc_block_indr_cleanup);
 716	tcf_block_setup(block, &bo);
 717
 718	return -EOPNOTSUPP;
 719}
 720
 721static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 722				  struct tcf_block_ext_info *ei,
 723				  struct netlink_ext_ack *extack)
 724{
 725	struct net_device *dev = q->dev_queue->dev;
 726	int err;
 727
 728	down_write(&block->cb_lock);
 729
 730	/* If tc offload feature is disabled and the block we try to bind
 731	 * to already has some offloaded filters, forbid to bind.
 732	 */
 733	if (dev->netdev_ops->ndo_setup_tc &&
 734	    !tc_can_offload(dev) &&
 735	    tcf_block_offload_in_use(block)) {
 736		NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 737		err = -EOPNOTSUPP;
 738		goto err_unlock;
 739	}
 740
 741	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_BIND, extack);
 742	if (err == -EOPNOTSUPP)
 743		goto no_offload_dev_inc;
 744	if (err)
 745		goto err_unlock;
 746
 747	up_write(&block->cb_lock);
 748	return 0;
 749
 750no_offload_dev_inc:
 751	if (tcf_block_offload_in_use(block))
 752		goto err_unlock;
 753
 754	err = 0;
 755	block->nooffloaddevcnt++;
 756err_unlock:
 757	up_write(&block->cb_lock);
 758	return err;
 759}
 760
 761static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 762				     struct tcf_block_ext_info *ei)
 763{
 764	struct net_device *dev = q->dev_queue->dev;
 765	int err;
 766
 767	down_write(&block->cb_lock);
 768	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_UNBIND, NULL);
 769	if (err == -EOPNOTSUPP)
 770		goto no_offload_dev_dec;
 771	up_write(&block->cb_lock);
 772	return;
 773
 774no_offload_dev_dec:
 775	WARN_ON(block->nooffloaddevcnt-- == 0);
 776	up_write(&block->cb_lock);
 777}
 778
 779static int
 780tcf_chain0_head_change_cb_add(struct tcf_block *block,
 781			      struct tcf_block_ext_info *ei,
 782			      struct netlink_ext_ack *extack)
 783{
 784	struct tcf_filter_chain_list_item *item;
 785	struct tcf_chain *chain0;
 786
 787	item = kmalloc(sizeof(*item), GFP_KERNEL);
 788	if (!item) {
 789		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 790		return -ENOMEM;
 791	}
 792	item->chain_head_change = ei->chain_head_change;
 793	item->chain_head_change_priv = ei->chain_head_change_priv;
 794
 795	mutex_lock(&block->lock);
 796	chain0 = block->chain0.chain;
 797	if (chain0)
 798		tcf_chain_hold(chain0);
 799	else
 800		list_add(&item->list, &block->chain0.filter_chain_list);
 801	mutex_unlock(&block->lock);
 802
 803	if (chain0) {
 804		struct tcf_proto *tp_head;
 805
 806		mutex_lock(&chain0->filter_chain_lock);
 807
 808		tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 809		if (tp_head)
 810			tcf_chain_head_change_item(item, tp_head);
 811
 812		mutex_lock(&block->lock);
 813		list_add(&item->list, &block->chain0.filter_chain_list);
 814		mutex_unlock(&block->lock);
 815
 816		mutex_unlock(&chain0->filter_chain_lock);
 817		tcf_chain_put(chain0);
 818	}
 819
 820	return 0;
 821}
 822
 823static void
 824tcf_chain0_head_change_cb_del(struct tcf_block *block,
 825			      struct tcf_block_ext_info *ei)
 826{
 827	struct tcf_filter_chain_list_item *item;
 828
 829	mutex_lock(&block->lock);
 830	list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 831		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 832		    (item->chain_head_change == ei->chain_head_change &&
 833		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 834			if (block->chain0.chain)
 835				tcf_chain_head_change_item(item, NULL);
 836			list_del(&item->list);
 837			mutex_unlock(&block->lock);
 838
 839			kfree(item);
 840			return;
 841		}
 842	}
 843	mutex_unlock(&block->lock);
 844	WARN_ON(1);
 845}
 846
 847struct tcf_net {
 848	spinlock_t idr_lock; /* Protects idr */
 849	struct idr idr;
 850};
 851
 852static unsigned int tcf_net_id;
 853
 854static int tcf_block_insert(struct tcf_block *block, struct net *net,
 855			    struct netlink_ext_ack *extack)
 856{
 857	struct tcf_net *tn = net_generic(net, tcf_net_id);
 858	int err;
 859
 860	idr_preload(GFP_KERNEL);
 861	spin_lock(&tn->idr_lock);
 862	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 863			    GFP_NOWAIT);
 864	spin_unlock(&tn->idr_lock);
 865	idr_preload_end();
 866
 867	return err;
 868}
 869
 870static void tcf_block_remove(struct tcf_block *block, struct net *net)
 871{
 872	struct tcf_net *tn = net_generic(net, tcf_net_id);
 873
 874	spin_lock(&tn->idr_lock);
 875	idr_remove(&tn->idr, block->index);
 876	spin_unlock(&tn->idr_lock);
 877}
 878
 879static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 880					  u32 block_index,
 881					  struct netlink_ext_ack *extack)
 882{
 883	struct tcf_block *block;
 884
 885	block = kzalloc(sizeof(*block), GFP_KERNEL);
 886	if (!block) {
 887		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 888		return ERR_PTR(-ENOMEM);
 889	}
 890	mutex_init(&block->lock);
 891	mutex_init(&block->proto_destroy_lock);
 892	init_rwsem(&block->cb_lock);
 893	flow_block_init(&block->flow_block);
 894	INIT_LIST_HEAD(&block->chain_list);
 895	INIT_LIST_HEAD(&block->owner_list);
 896	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 897
 898	refcount_set(&block->refcnt, 1);
 899	block->net = net;
 900	block->index = block_index;
 901
 902	/* Don't store q pointer for blocks which are shared */
 903	if (!tcf_block_shared(block))
 904		block->q = q;
 905	return block;
 906}
 907
 908static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 909{
 910	struct tcf_net *tn = net_generic(net, tcf_net_id);
 911
 912	return idr_find(&tn->idr, block_index);
 913}
 914
 915static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
 916{
 917	struct tcf_block *block;
 918
 919	rcu_read_lock();
 920	block = tcf_block_lookup(net, block_index);
 921	if (block && !refcount_inc_not_zero(&block->refcnt))
 922		block = NULL;
 923	rcu_read_unlock();
 924
 925	return block;
 926}
 927
 928static struct tcf_chain *
 929__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 930{
 931	mutex_lock(&block->lock);
 932	if (chain)
 933		chain = list_is_last(&chain->list, &block->chain_list) ?
 934			NULL : list_next_entry(chain, list);
 935	else
 936		chain = list_first_entry_or_null(&block->chain_list,
 937						 struct tcf_chain, list);
 938
 939	/* skip all action-only chains */
 940	while (chain && tcf_chain_held_by_acts_only(chain))
 941		chain = list_is_last(&chain->list, &block->chain_list) ?
 942			NULL : list_next_entry(chain, list);
 943
 944	if (chain)
 945		tcf_chain_hold(chain);
 946	mutex_unlock(&block->lock);
 947
 948	return chain;
 949}
 950
 951/* Function to be used by all clients that want to iterate over all chains on
 952 * block. It properly obtains block->lock and takes reference to chain before
 953 * returning it. Users of this function must be tolerant to concurrent chain
 954 * insertion/deletion or ensure that no concurrent chain modification is
 955 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 956 * consistent dump because rtnl lock is released each time skb is filled with
 957 * data and sent to user-space.
 958 */
 959
 960struct tcf_chain *
 961tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 962{
 963	struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
 964
 965	if (chain)
 966		tcf_chain_put(chain);
 967
 968	return chain_next;
 969}
 970EXPORT_SYMBOL(tcf_get_next_chain);
 971
 972static struct tcf_proto *
 973__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 974{
 975	u32 prio = 0;
 976
 977	ASSERT_RTNL();
 978	mutex_lock(&chain->filter_chain_lock);
 979
 980	if (!tp) {
 981		tp = tcf_chain_dereference(chain->filter_chain, chain);
 982	} else if (tcf_proto_is_deleting(tp)) {
 983		/* 'deleting' flag is set and chain->filter_chain_lock was
 984		 * unlocked, which means next pointer could be invalid. Restart
 985		 * search.
 986		 */
 987		prio = tp->prio + 1;
 988		tp = tcf_chain_dereference(chain->filter_chain, chain);
 989
 990		for (; tp; tp = tcf_chain_dereference(tp->next, chain))
 991			if (!tp->deleting && tp->prio >= prio)
 992				break;
 993	} else {
 994		tp = tcf_chain_dereference(tp->next, chain);
 995	}
 996
 997	if (tp)
 998		tcf_proto_get(tp);
 999
1000	mutex_unlock(&chain->filter_chain_lock);
1001
1002	return tp;
1003}
1004
1005/* Function to be used by all clients that want to iterate over all tp's on
1006 * chain. Users of this function must be tolerant to concurrent tp
1007 * insertion/deletion or ensure that no concurrent chain modification is
1008 * possible. Note that all netlink dump callbacks cannot guarantee to provide
1009 * consistent dump because rtnl lock is released each time skb is filled with
1010 * data and sent to user-space.
1011 */
1012
1013struct tcf_proto *
1014tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
1015{
1016	struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
1017
1018	if (tp)
1019		tcf_proto_put(tp, true, NULL);
1020
1021	return tp_next;
1022}
1023EXPORT_SYMBOL(tcf_get_next_proto);
1024
1025static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1026{
1027	struct tcf_chain *chain;
1028
1029	/* Last reference to block. At this point chains cannot be added or
1030	 * removed concurrently.
1031	 */
1032	for (chain = tcf_get_next_chain(block, NULL);
1033	     chain;
1034	     chain = tcf_get_next_chain(block, chain)) {
1035		tcf_chain_put_explicitly_created(chain);
1036		tcf_chain_flush(chain, rtnl_held);
1037	}
1038}
1039
1040/* Lookup Qdisc and increments its reference counter.
1041 * Set parent, if necessary.
1042 */
1043
1044static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1045			    u32 *parent, int ifindex, bool rtnl_held,
1046			    struct netlink_ext_ack *extack)
1047{
1048	const struct Qdisc_class_ops *cops;
1049	struct net_device *dev;
1050	int err = 0;
1051
1052	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1053		return 0;
1054
1055	rcu_read_lock();
1056
1057	/* Find link */
1058	dev = dev_get_by_index_rcu(net, ifindex);
1059	if (!dev) {
1060		rcu_read_unlock();
1061		return -ENODEV;
1062	}
 
 
 
1063
1064	/* Find qdisc */
1065	if (!*parent) {
1066		*q = rcu_dereference(dev->qdisc);
1067		*parent = (*q)->handle;
1068	} else {
1069		*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1070		if (!*q) {
1071			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1072			err = -EINVAL;
1073			goto errout_rcu;
1074		}
1075	}
1076
1077	*q = qdisc_refcount_inc_nz(*q);
1078	if (!*q) {
1079		NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1080		err = -EINVAL;
1081		goto errout_rcu;
1082	}
1083
1084	/* Is it classful? */
1085	cops = (*q)->ops->cl_ops;
1086	if (!cops) {
1087		NL_SET_ERR_MSG(extack, "Qdisc not classful");
1088		err = -EINVAL;
1089		goto errout_qdisc;
1090	}
1091
1092	if (!cops->tcf_block) {
1093		NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1094		err = -EOPNOTSUPP;
1095		goto errout_qdisc;
1096	}
1097
1098errout_rcu:
1099	/* At this point we know that qdisc is not noop_qdisc,
1100	 * which means that qdisc holds a reference to net_device
1101	 * and we hold a reference to qdisc, so it is safe to release
1102	 * rcu read lock.
1103	 */
1104	rcu_read_unlock();
1105	return err;
1106
1107errout_qdisc:
1108	rcu_read_unlock();
1109
1110	if (rtnl_held)
1111		qdisc_put(*q);
1112	else
1113		qdisc_put_unlocked(*q);
1114	*q = NULL;
1115
1116	return err;
1117}
1118
1119static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1120			       int ifindex, struct netlink_ext_ack *extack)
1121{
1122	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1123		return 0;
1124
1125	/* Do we search for filter, attached to class? */
1126	if (TC_H_MIN(parent)) {
1127		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1128
1129		*cl = cops->find(q, parent);
1130		if (*cl == 0) {
1131			NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1132			return -ENOENT;
1133		}
1134	}
1135
1136	return 0;
1137}
1138
1139static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1140					  unsigned long cl, int ifindex,
1141					  u32 block_index,
1142					  struct netlink_ext_ack *extack)
1143{
1144	struct tcf_block *block;
1145
1146	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1147		block = tcf_block_refcnt_get(net, block_index);
1148		if (!block) {
1149			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1150			return ERR_PTR(-EINVAL);
1151		}
1152	} else {
1153		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1154
1155		block = cops->tcf_block(q, cl, extack);
1156		if (!block)
1157			return ERR_PTR(-EINVAL);
1158
1159		if (tcf_block_shared(block)) {
1160			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1161			return ERR_PTR(-EOPNOTSUPP);
1162		}
1163
1164		/* Always take reference to block in order to support execution
1165		 * of rules update path of cls API without rtnl lock. Caller
1166		 * must release block when it is finished using it. 'if' block
1167		 * of this conditional obtain reference to block by calling
1168		 * tcf_block_refcnt_get().
1169		 */
1170		refcount_inc(&block->refcnt);
1171	}
1172
1173	return block;
1174}
1175
1176static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1177			    struct tcf_block_ext_info *ei, bool rtnl_held)
1178{
1179	if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1180		/* Flushing/putting all chains will cause the block to be
1181		 * deallocated when last chain is freed. However, if chain_list
1182		 * is empty, block has to be manually deallocated. After block
1183		 * reference counter reached 0, it is no longer possible to
1184		 * increment it or add new chains to block.
1185		 */
1186		bool free_block = list_empty(&block->chain_list);
1187
1188		mutex_unlock(&block->lock);
1189		if (tcf_block_shared(block))
1190			tcf_block_remove(block, block->net);
1191
1192		if (q)
1193			tcf_block_offload_unbind(block, q, ei);
1194
1195		if (free_block)
1196			tcf_block_destroy(block);
1197		else
1198			tcf_block_flush_all_chains(block, rtnl_held);
1199	} else if (q) {
1200		tcf_block_offload_unbind(block, q, ei);
1201	}
1202}
1203
1204static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1205{
1206	__tcf_block_put(block, NULL, NULL, rtnl_held);
1207}
1208
1209/* Find tcf block.
1210 * Set q, parent, cl when appropriate.
1211 */
1212
1213static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1214					u32 *parent, unsigned long *cl,
1215					int ifindex, u32 block_index,
1216					struct netlink_ext_ack *extack)
1217{
1218	struct tcf_block *block;
1219	int err = 0;
1220
1221	ASSERT_RTNL();
1222
1223	err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1224	if (err)
1225		goto errout;
1226
1227	err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1228	if (err)
1229		goto errout_qdisc;
1230
1231	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1232	if (IS_ERR(block)) {
1233		err = PTR_ERR(block);
1234		goto errout_qdisc;
1235	}
1236
1237	return block;
1238
1239errout_qdisc:
1240	if (*q)
1241		qdisc_put(*q);
1242errout:
1243	*q = NULL;
1244	return ERR_PTR(err);
1245}
1246
1247static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1248			      bool rtnl_held)
1249{
1250	if (!IS_ERR_OR_NULL(block))
1251		tcf_block_refcnt_put(block, rtnl_held);
1252
1253	if (q) {
1254		if (rtnl_held)
1255			qdisc_put(q);
1256		else
1257			qdisc_put_unlocked(q);
1258	}
1259}
1260
1261struct tcf_block_owner_item {
1262	struct list_head list;
1263	struct Qdisc *q;
1264	enum flow_block_binder_type binder_type;
1265};
1266
1267static void
1268tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1269			       struct Qdisc *q,
1270			       enum flow_block_binder_type binder_type)
1271{
1272	if (block->keep_dst &&
1273	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1274	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1275		netif_keep_dst(qdisc_dev(q));
1276}
1277
1278void tcf_block_netif_keep_dst(struct tcf_block *block)
1279{
1280	struct tcf_block_owner_item *item;
1281
1282	block->keep_dst = true;
1283	list_for_each_entry(item, &block->owner_list, list)
1284		tcf_block_owner_netif_keep_dst(block, item->q,
1285					       item->binder_type);
1286}
1287EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1288
1289static int tcf_block_owner_add(struct tcf_block *block,
1290			       struct Qdisc *q,
1291			       enum flow_block_binder_type binder_type)
1292{
1293	struct tcf_block_owner_item *item;
1294
1295	item = kmalloc(sizeof(*item), GFP_KERNEL);
1296	if (!item)
1297		return -ENOMEM;
1298	item->q = q;
1299	item->binder_type = binder_type;
1300	list_add(&item->list, &block->owner_list);
1301	return 0;
1302}
1303
1304static void tcf_block_owner_del(struct tcf_block *block,
1305				struct Qdisc *q,
1306				enum flow_block_binder_type binder_type)
1307{
1308	struct tcf_block_owner_item *item;
1309
1310	list_for_each_entry(item, &block->owner_list, list) {
1311		if (item->q == q && item->binder_type == binder_type) {
1312			list_del(&item->list);
1313			kfree(item);
1314			return;
1315		}
1316	}
1317	WARN_ON(1);
1318}
1319
1320int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1321		      struct tcf_block_ext_info *ei,
1322		      struct netlink_ext_ack *extack)
1323{
1324	struct net *net = qdisc_net(q);
1325	struct tcf_block *block = NULL;
1326	int err;
1327
1328	if (ei->block_index)
1329		/* block_index not 0 means the shared block is requested */
1330		block = tcf_block_refcnt_get(net, ei->block_index);
1331
1332	if (!block) {
1333		block = tcf_block_create(net, q, ei->block_index, extack);
1334		if (IS_ERR(block))
1335			return PTR_ERR(block);
1336		if (tcf_block_shared(block)) {
1337			err = tcf_block_insert(block, net, extack);
1338			if (err)
1339				goto err_block_insert;
1340		}
1341	}
1342
1343	err = tcf_block_owner_add(block, q, ei->binder_type);
1344	if (err)
1345		goto err_block_owner_add;
1346
1347	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
 
 
 
1348
1349	err = tcf_chain0_head_change_cb_add(block, ei, extack);
1350	if (err)
1351		goto err_chain0_head_change_cb_add;
1352
1353	err = tcf_block_offload_bind(block, q, ei, extack);
1354	if (err)
1355		goto err_block_offload_bind;
1356
1357	*p_block = block;
1358	return 0;
 
 
 
 
 
 
 
 
1359
1360err_block_offload_bind:
1361	tcf_chain0_head_change_cb_del(block, ei);
1362err_chain0_head_change_cb_add:
1363	tcf_block_owner_del(block, q, ei->binder_type);
1364err_block_owner_add:
1365err_block_insert:
1366	tcf_block_refcnt_put(block, true);
1367	return err;
1368}
1369EXPORT_SYMBOL(tcf_block_get_ext);
1370
1371static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1372{
1373	struct tcf_proto __rcu **p_filter_chain = priv;
1374
1375	rcu_assign_pointer(*p_filter_chain, tp_head);
1376}
1377
1378int tcf_block_get(struct tcf_block **p_block,
1379		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1380		  struct netlink_ext_ack *extack)
1381{
1382	struct tcf_block_ext_info ei = {
1383		.chain_head_change = tcf_chain_head_change_dflt,
1384		.chain_head_change_priv = p_filter_chain,
1385	};
1386
1387	WARN_ON(!p_filter_chain);
1388	return tcf_block_get_ext(p_block, q, &ei, extack);
1389}
1390EXPORT_SYMBOL(tcf_block_get);
1391
1392/* XXX: Standalone actions are not allowed to jump to any chain, and bound
1393 * actions should be all removed after flushing.
1394 */
1395void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1396		       struct tcf_block_ext_info *ei)
1397{
1398	if (!block)
1399		return;
1400	tcf_chain0_head_change_cb_del(block, ei);
1401	tcf_block_owner_del(block, q, ei->binder_type);
1402
1403	__tcf_block_put(block, q, ei, true);
1404}
1405EXPORT_SYMBOL(tcf_block_put_ext);
1406
1407void tcf_block_put(struct tcf_block *block)
1408{
1409	struct tcf_block_ext_info ei = {0, };
1410
1411	if (!block)
1412		return;
1413	tcf_block_put_ext(block, block->q, &ei);
1414}
1415
1416EXPORT_SYMBOL(tcf_block_put);
1417
1418static int
1419tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1420			    void *cb_priv, bool add, bool offload_in_use,
1421			    struct netlink_ext_ack *extack)
1422{
1423	struct tcf_chain *chain, *chain_prev;
1424	struct tcf_proto *tp, *tp_prev;
1425	int err;
1426
1427	lockdep_assert_held(&block->cb_lock);
1428
1429	for (chain = __tcf_get_next_chain(block, NULL);
1430	     chain;
1431	     chain_prev = chain,
1432		     chain = __tcf_get_next_chain(block, chain),
1433		     tcf_chain_put(chain_prev)) {
1434		for (tp = __tcf_get_next_proto(chain, NULL); tp;
1435		     tp_prev = tp,
1436			     tp = __tcf_get_next_proto(chain, tp),
1437			     tcf_proto_put(tp_prev, true, NULL)) {
1438			if (tp->ops->reoffload) {
1439				err = tp->ops->reoffload(tp, add, cb, cb_priv,
1440							 extack);
1441				if (err && add)
1442					goto err_playback_remove;
1443			} else if (add && offload_in_use) {
1444				err = -EOPNOTSUPP;
1445				NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1446				goto err_playback_remove;
1447			}
 
 
 
1448		}
1449	}
1450
1451	return 0;
1452
1453err_playback_remove:
1454	tcf_proto_put(tp, true, NULL);
1455	tcf_chain_put(chain);
1456	tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1457				    extack);
1458	return err;
1459}
1460
1461static int tcf_block_bind(struct tcf_block *block,
1462			  struct flow_block_offload *bo)
1463{
1464	struct flow_block_cb *block_cb, *next;
1465	int err, i = 0;
1466
1467	lockdep_assert_held(&block->cb_lock);
1468
1469	list_for_each_entry(block_cb, &bo->cb_list, list) {
1470		err = tcf_block_playback_offloads(block, block_cb->cb,
1471						  block_cb->cb_priv, true,
1472						  tcf_block_offload_in_use(block),
1473						  bo->extack);
1474		if (err)
1475			goto err_unroll;
1476		if (!bo->unlocked_driver_cb)
1477			block->lockeddevcnt++;
1478
1479		i++;
1480	}
1481	list_splice(&bo->cb_list, &block->flow_block.cb_list);
1482
1483	return 0;
1484
1485err_unroll:
1486	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1487		if (i-- > 0) {
1488			list_del(&block_cb->list);
1489			tcf_block_playback_offloads(block, block_cb->cb,
1490						    block_cb->cb_priv, false,
1491						    tcf_block_offload_in_use(block),
1492						    NULL);
1493			if (!bo->unlocked_driver_cb)
1494				block->lockeddevcnt--;
1495		}
1496		flow_block_cb_free(block_cb);
1497	}
1498
1499	return err;
1500}
1501
1502static void tcf_block_unbind(struct tcf_block *block,
1503			     struct flow_block_offload *bo)
1504{
1505	struct flow_block_cb *block_cb, *next;
1506
1507	lockdep_assert_held(&block->cb_lock);
1508
1509	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1510		tcf_block_playback_offloads(block, block_cb->cb,
1511					    block_cb->cb_priv, false,
1512					    tcf_block_offload_in_use(block),
1513					    NULL);
1514		list_del(&block_cb->list);
1515		flow_block_cb_free(block_cb);
1516		if (!bo->unlocked_driver_cb)
1517			block->lockeddevcnt--;
1518	}
1519}
1520
1521static int tcf_block_setup(struct tcf_block *block,
1522			   struct flow_block_offload *bo)
1523{
1524	int err;
1525
1526	switch (bo->command) {
1527	case FLOW_BLOCK_BIND:
1528		err = tcf_block_bind(block, bo);
1529		break;
1530	case FLOW_BLOCK_UNBIND:
1531		err = 0;
1532		tcf_block_unbind(block, bo);
1533		break;
1534	default:
1535		WARN_ON_ONCE(1);
1536		err = -EOPNOTSUPP;
1537	}
1538
1539	return err;
1540}
1541
1542/* Main classifier routine: scans classifier chain attached
1543 * to this qdisc, (optionally) tests for protocol and asks
1544 * specific classifiers.
1545 */
1546static inline int __tcf_classify(struct sk_buff *skb,
1547				 const struct tcf_proto *tp,
1548				 const struct tcf_proto *orig_tp,
1549				 struct tcf_result *res,
1550				 bool compat_mode,
1551				 u32 *last_executed_chain)
1552{
1553#ifdef CONFIG_NET_CLS_ACT
1554	const int max_reclassify_loop = 16;
1555	const struct tcf_proto *first_tp;
1556	int limit = 0;
1557
1558reclassify:
1559#endif
1560	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1561		__be16 protocol = skb_protocol(skb, false);
1562		int err;
1563
1564		if (tp->protocol != protocol &&
1565		    tp->protocol != htons(ETH_P_ALL))
1566			continue;
1567
1568		err = tc_classify(skb, tp, res);
1569#ifdef CONFIG_NET_CLS_ACT
1570		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1571			first_tp = orig_tp;
1572			*last_executed_chain = first_tp->chain->index;
1573			goto reset;
1574		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1575			first_tp = res->goto_tp;
1576			*last_executed_chain = err & TC_ACT_EXT_VAL_MASK;
1577			goto reset;
1578		}
1579#endif
1580		if (err >= 0)
1581			return err;
1582	}
1583
1584	return TC_ACT_UNSPEC; /* signal: continue lookup */
1585#ifdef CONFIG_NET_CLS_ACT
1586reset:
1587	if (unlikely(limit++ >= max_reclassify_loop)) {
1588		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1589				       tp->chain->block->index,
1590				       tp->prio & 0xffff,
1591				       ntohs(tp->protocol));
1592		return TC_ACT_SHOT;
1593	}
1594
1595	tp = first_tp;
1596	goto reclassify;
1597#endif
1598}
1599
1600int tcf_classify(struct sk_buff *skb,
1601		 const struct tcf_block *block,
1602		 const struct tcf_proto *tp,
1603		 struct tcf_result *res, bool compat_mode)
1604{
1605#if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1606	u32 last_executed_chain = 0;
1607
1608	return __tcf_classify(skb, tp, tp, res, compat_mode,
1609			      &last_executed_chain);
1610#else
1611	u32 last_executed_chain = tp ? tp->chain->index : 0;
1612	const struct tcf_proto *orig_tp = tp;
1613	struct tc_skb_ext *ext;
1614	int ret;
1615
1616	if (block) {
1617		ext = skb_ext_find(skb, TC_SKB_EXT);
1618
1619		if (ext && ext->chain) {
1620			struct tcf_chain *fchain;
1621
1622			fchain = tcf_chain_lookup_rcu(block, ext->chain);
1623			if (!fchain)
1624				return TC_ACT_SHOT;
1625
1626			/* Consume, so cloned/redirect skbs won't inherit ext */
1627			skb_ext_del(skb, TC_SKB_EXT);
1628
1629			tp = rcu_dereference_bh(fchain->filter_chain);
1630			last_executed_chain = fchain->index;
1631		}
1632	}
1633
1634	ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,
1635			     &last_executed_chain);
1636
1637	if (tc_skb_ext_tc_enabled()) {
1638		/* If we missed on some chain */
1639		if (ret == TC_ACT_UNSPEC && last_executed_chain) {
1640			struct tc_skb_cb *cb = tc_skb_cb(skb);
1641
1642			ext = tc_skb_ext_alloc(skb);
1643			if (WARN_ON_ONCE(!ext))
1644				return TC_ACT_SHOT;
1645			ext->chain = last_executed_chain;
1646			ext->mru = cb->mru;
1647			ext->post_ct = cb->post_ct;
1648			ext->post_ct_snat = cb->post_ct_snat;
1649			ext->post_ct_dnat = cb->post_ct_dnat;
1650			ext->zone = cb->zone;
1651		}
1652	}
1653
1654	return ret;
1655#endif
1656}
1657EXPORT_SYMBOL(tcf_classify);
1658
1659struct tcf_chain_info {
1660	struct tcf_proto __rcu **pprev;
1661	struct tcf_proto __rcu *next;
1662};
1663
1664static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1665					   struct tcf_chain_info *chain_info)
1666{
1667	return tcf_chain_dereference(*chain_info->pprev, chain);
1668}
1669
1670static int tcf_chain_tp_insert(struct tcf_chain *chain,
1671			       struct tcf_chain_info *chain_info,
1672			       struct tcf_proto *tp)
1673{
1674	if (chain->flushing)
1675		return -EAGAIN;
1676
1677	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1678	if (*chain_info->pprev == chain->filter_chain)
1679		tcf_chain0_head_change(chain, tp);
1680	tcf_proto_get(tp);
1681	rcu_assign_pointer(*chain_info->pprev, tp);
1682
1683	return 0;
1684}
1685
1686static void tcf_chain_tp_remove(struct tcf_chain *chain,
1687				struct tcf_chain_info *chain_info,
1688				struct tcf_proto *tp)
1689{
1690	struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1691
1692	tcf_proto_mark_delete(tp);
1693	if (tp == chain->filter_chain)
1694		tcf_chain0_head_change(chain, next);
1695	RCU_INIT_POINTER(*chain_info->pprev, next);
1696}
1697
1698static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1699					   struct tcf_chain_info *chain_info,
1700					   u32 protocol, u32 prio,
1701					   bool prio_allocate);
1702
1703/* Try to insert new proto.
1704 * If proto with specified priority already exists, free new proto
1705 * and return existing one.
1706 */
1707
1708static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1709						    struct tcf_proto *tp_new,
1710						    u32 protocol, u32 prio,
1711						    bool rtnl_held)
1712{
1713	struct tcf_chain_info chain_info;
1714	struct tcf_proto *tp;
1715	int err = 0;
1716
1717	mutex_lock(&chain->filter_chain_lock);
1718
1719	if (tcf_proto_exists_destroying(chain, tp_new)) {
1720		mutex_unlock(&chain->filter_chain_lock);
1721		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1722		return ERR_PTR(-EAGAIN);
1723	}
1724
1725	tp = tcf_chain_tp_find(chain, &chain_info,
1726			       protocol, prio, false);
1727	if (!tp)
1728		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1729	mutex_unlock(&chain->filter_chain_lock);
1730
1731	if (tp) {
1732		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1733		tp_new = tp;
1734	} else if (err) {
1735		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1736		tp_new = ERR_PTR(err);
1737	}
1738
1739	return tp_new;
1740}
1741
1742static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1743				      struct tcf_proto *tp, bool rtnl_held,
1744				      struct netlink_ext_ack *extack)
1745{
1746	struct tcf_chain_info chain_info;
1747	struct tcf_proto *tp_iter;
1748	struct tcf_proto **pprev;
1749	struct tcf_proto *next;
1750
1751	mutex_lock(&chain->filter_chain_lock);
1752
1753	/* Atomically find and remove tp from chain. */
1754	for (pprev = &chain->filter_chain;
1755	     (tp_iter = tcf_chain_dereference(*pprev, chain));
1756	     pprev = &tp_iter->next) {
1757		if (tp_iter == tp) {
1758			chain_info.pprev = pprev;
1759			chain_info.next = tp_iter->next;
1760			WARN_ON(tp_iter->deleting);
1761			break;
 
 
 
 
 
 
 
 
 
 
 
1762		}
1763	}
1764	/* Verify that tp still exists and no new filters were inserted
1765	 * concurrently.
1766	 * Mark tp for deletion if it is empty.
1767	 */
1768	if (!tp_iter || !tcf_proto_check_delete(tp)) {
1769		mutex_unlock(&chain->filter_chain_lock);
1770		return;
1771	}
1772
1773	tcf_proto_signal_destroying(chain, tp);
1774	next = tcf_chain_dereference(chain_info.next, chain);
1775	if (tp == chain->filter_chain)
1776		tcf_chain0_head_change(chain, next);
1777	RCU_INIT_POINTER(*chain_info.pprev, next);
1778	mutex_unlock(&chain->filter_chain_lock);
1779
1780	tcf_proto_put(tp, rtnl_held, extack);
1781}
1782
1783static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1784					   struct tcf_chain_info *chain_info,
1785					   u32 protocol, u32 prio,
1786					   bool prio_allocate)
1787{
1788	struct tcf_proto **pprev;
1789	struct tcf_proto *tp;
1790
1791	/* Check the chain for existence of proto-tcf with this priority */
1792	for (pprev = &chain->filter_chain;
1793	     (tp = tcf_chain_dereference(*pprev, chain));
1794	     pprev = &tp->next) {
1795		if (tp->prio >= prio) {
1796			if (tp->prio == prio) {
1797				if (prio_allocate ||
1798				    (tp->protocol != protocol && protocol))
1799					return ERR_PTR(-EINVAL);
1800			} else {
1801				tp = NULL;
1802			}
1803			break;
1804		}
1805	}
1806	chain_info->pprev = pprev;
1807	if (tp) {
1808		chain_info->next = tp->next;
1809		tcf_proto_get(tp);
1810	} else {
1811		chain_info->next = NULL;
 
1812	}
1813	return tp;
 
 
 
 
 
 
 
1814}
1815
1816static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1817			 struct tcf_proto *tp, struct tcf_block *block,
1818			 struct Qdisc *q, u32 parent, void *fh,
1819			 u32 portid, u32 seq, u16 flags, int event,
1820			 bool terse_dump, bool rtnl_held)
1821{
1822	struct tcmsg *tcm;
1823	struct nlmsghdr  *nlh;
1824	unsigned char *b = skb_tail_pointer(skb);
1825
1826	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1827	if (!nlh)
1828		goto out_nlmsg_trim;
1829	tcm = nlmsg_data(nlh);
1830	tcm->tcm_family = AF_UNSPEC;
1831	tcm->tcm__pad1 = 0;
1832	tcm->tcm__pad2 = 0;
1833	if (q) {
1834		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1835		tcm->tcm_parent = parent;
1836	} else {
1837		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1838		tcm->tcm_block_index = block->index;
1839	}
1840	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1841	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1842		goto nla_put_failure;
1843	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1844		goto nla_put_failure;
1845	if (!fh) {
1846		tcm->tcm_handle = 0;
1847	} else if (terse_dump) {
1848		if (tp->ops->terse_dump) {
1849			if (tp->ops->terse_dump(net, tp, fh, skb, tcm,
1850						rtnl_held) < 0)
1851				goto nla_put_failure;
1852		} else {
1853			goto cls_op_not_supp;
1854		}
1855	} else {
1856		if (tp->ops->dump &&
1857		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1858			goto nla_put_failure;
1859	}
1860	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1861	return skb->len;
1862
1863out_nlmsg_trim:
1864nla_put_failure:
1865cls_op_not_supp:
1866	nlmsg_trim(skb, b);
1867	return -1;
1868}
1869
1870static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1871			  struct nlmsghdr *n, struct tcf_proto *tp,
1872			  struct tcf_block *block, struct Qdisc *q,
1873			  u32 parent, void *fh, int event, bool unicast,
1874			  bool rtnl_held)
1875{
1876	struct sk_buff *skb;
1877	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1878	int err = 0;
1879
1880	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1881	if (!skb)
1882		return -ENOBUFS;
1883
1884	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1885			  n->nlmsg_seq, n->nlmsg_flags, event,
1886			  false, rtnl_held) <= 0) {
1887		kfree_skb(skb);
1888		return -EINVAL;
1889	}
1890
1891	if (unicast)
1892		err = rtnl_unicast(skb, net, portid);
1893	else
1894		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1895				     n->nlmsg_flags & NLM_F_ECHO);
1896	return err;
1897}
1898
1899static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1900			      struct nlmsghdr *n, struct tcf_proto *tp,
1901			      struct tcf_block *block, struct Qdisc *q,
1902			      u32 parent, void *fh, bool unicast, bool *last,
1903			      bool rtnl_held, struct netlink_ext_ack *extack)
1904{
1905	struct sk_buff *skb;
1906	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1907	int err;
1908
1909	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1910	if (!skb)
1911		return -ENOBUFS;
1912
1913	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1914			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1915			  false, rtnl_held) <= 0) {
1916		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1917		kfree_skb(skb);
1918		return -EINVAL;
1919	}
1920
1921	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1922	if (err) {
1923		kfree_skb(skb);
1924		return err;
1925	}
1926
1927	if (unicast)
1928		err = rtnl_unicast(skb, net, portid);
1929	else
1930		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1931				     n->nlmsg_flags & NLM_F_ECHO);
1932	if (err < 0)
1933		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1934
1935	return err;
1936}
1937
1938static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1939				 struct tcf_block *block, struct Qdisc *q,
1940				 u32 parent, struct nlmsghdr *n,
1941				 struct tcf_chain *chain, int event)
1942{
1943	struct tcf_proto *tp;
1944
1945	for (tp = tcf_get_next_proto(chain, NULL);
1946	     tp; tp = tcf_get_next_proto(chain, tp))
1947		tfilter_notify(net, oskb, n, tp, block,
1948			       q, parent, NULL, event, false, true);
1949}
1950
1951static void tfilter_put(struct tcf_proto *tp, void *fh)
1952{
1953	if (tp->ops->put && fh)
1954		tp->ops->put(tp, fh);
1955}
1956
1957static bool is_qdisc_ingress(__u32 classid)
1958{
1959	return (TC_H_MIN(classid) == TC_H_MIN(TC_H_MIN_INGRESS));
1960}
1961
1962static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1963			  struct netlink_ext_ack *extack)
1964{
1965	struct net *net = sock_net(skb->sk);
1966	struct nlattr *tca[TCA_MAX + 1];
1967	char name[IFNAMSIZ];
1968	struct tcmsg *t;
1969	u32 protocol;
1970	u32 prio;
1971	bool prio_allocate;
1972	u32 parent;
1973	u32 chain_index;
1974	struct Qdisc *q;
1975	struct tcf_chain_info chain_info;
1976	struct tcf_chain *chain;
1977	struct tcf_block *block;
1978	struct tcf_proto *tp;
1979	unsigned long cl;
1980	void *fh;
1981	int err;
1982	int tp_created;
1983	bool rtnl_held = false;
1984	u32 flags;
1985
1986replay:
1987	tp_created = 0;
1988
1989	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
1990				     rtm_tca_policy, extack);
1991	if (err < 0)
1992		return err;
1993
1994	t = nlmsg_data(n);
1995	protocol = TC_H_MIN(t->tcm_info);
1996	prio = TC_H_MAJ(t->tcm_info);
1997	prio_allocate = false;
1998	parent = t->tcm_parent;
1999	tp = NULL;
2000	cl = 0;
2001	block = NULL;
2002	q = NULL;
2003	chain = NULL;
2004	flags = 0;
2005
2006	if (prio == 0) {
2007		/* If no priority is provided by the user,
2008		 * we allocate one.
2009		 */
2010		if (n->nlmsg_flags & NLM_F_CREATE) {
2011			prio = TC_H_MAKE(0x80000000U, 0U);
2012			prio_allocate = true;
2013		} else {
2014			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2015			return -ENOENT;
2016		}
2017	}
2018
2019	/* Find head of filter chain. */
2020
2021	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2022	if (err)
2023		return err;
2024
2025	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2026		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2027		err = -EINVAL;
2028		goto errout;
2029	}
2030
2031	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
2032	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
2033	 * type is not specified, classifier is not unlocked.
2034	 */
2035	if (rtnl_held ||
2036	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2037	    !tcf_proto_is_unlocked(name)) {
2038		rtnl_held = true;
2039		rtnl_lock();
2040	}
2041
2042	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2043	if (err)
2044		goto errout;
2045
2046	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2047				 extack);
2048	if (IS_ERR(block)) {
2049		err = PTR_ERR(block);
2050		goto errout;
2051	}
2052	block->classid = parent;
2053
2054	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2055	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2056		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2057		err = -EINVAL;
2058		goto errout;
2059	}
2060	chain = tcf_chain_get(block, chain_index, true);
2061	if (!chain) {
2062		NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2063		err = -ENOMEM;
2064		goto errout;
2065	}
2066
2067	mutex_lock(&chain->filter_chain_lock);
2068	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2069			       prio, prio_allocate);
2070	if (IS_ERR(tp)) {
2071		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2072		err = PTR_ERR(tp);
2073		goto errout_locked;
2074	}
2075
2076	if (tp == NULL) {
2077		struct tcf_proto *tp_new = NULL;
2078
2079		if (chain->flushing) {
2080			err = -EAGAIN;
2081			goto errout_locked;
2082		}
2083
2084		/* Proto-tcf does not exist, create new one */
2085
2086		if (tca[TCA_KIND] == NULL || !protocol) {
2087			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2088			err = -EINVAL;
2089			goto errout_locked;
2090		}
2091
2092		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2093			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2094			err = -ENOENT;
2095			goto errout_locked;
2096		}
2097
2098		if (prio_allocate)
2099			prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2100							       &chain_info));
2101
2102		mutex_unlock(&chain->filter_chain_lock);
2103		tp_new = tcf_proto_create(name, protocol, prio, chain,
2104					  rtnl_held, extack);
2105		if (IS_ERR(tp_new)) {
2106			err = PTR_ERR(tp_new);
2107			goto errout_tp;
2108		}
2109
2110		tp_created = 1;
2111		tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2112						rtnl_held);
2113		if (IS_ERR(tp)) {
2114			err = PTR_ERR(tp);
2115			goto errout_tp;
2116		}
2117	} else {
2118		mutex_unlock(&chain->filter_chain_lock);
2119	}
2120
2121	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2122		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2123		err = -EINVAL;
2124		goto errout;
2125	}
2126
2127	fh = tp->ops->get(tp, t->tcm_handle);
2128
2129	if (!fh) {
2130		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2131			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2132			err = -ENOENT;
2133			goto errout;
2134		}
2135	} else if (n->nlmsg_flags & NLM_F_EXCL) {
2136		tfilter_put(tp, fh);
2137		NL_SET_ERR_MSG(extack, "Filter already exists");
2138		err = -EEXIST;
2139		goto errout;
2140	}
2141
2142	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2143		tfilter_put(tp, fh);
2144		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2145		err = -EINVAL;
2146		goto errout;
2147	}
2148
2149	if (!(n->nlmsg_flags & NLM_F_CREATE))
2150		flags |= TCA_ACT_FLAGS_REPLACE;
2151	if (!rtnl_held)
2152		flags |= TCA_ACT_FLAGS_NO_RTNL;
2153	if (is_qdisc_ingress(parent))
2154		flags |= TCA_ACT_FLAGS_AT_INGRESS;
2155	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2156			      flags, extack);
2157	if (err == 0) {
2158		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2159			       RTM_NEWTFILTER, false, rtnl_held);
2160		tfilter_put(tp, fh);
2161		/* q pointer is NULL for shared blocks */
2162		if (q)
2163			q->flags &= ~TCQ_F_CAN_BYPASS;
2164	}
2165
2166errout:
2167	if (err && tp_created)
2168		tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2169errout_tp:
2170	if (chain) {
2171		if (tp && !IS_ERR(tp))
2172			tcf_proto_put(tp, rtnl_held, NULL);
2173		if (!tp_created)
2174			tcf_chain_put(chain);
2175	}
2176	tcf_block_release(q, block, rtnl_held);
2177
2178	if (rtnl_held)
2179		rtnl_unlock();
2180
2181	if (err == -EAGAIN) {
2182		/* Take rtnl lock in case EAGAIN is caused by concurrent flush
2183		 * of target chain.
2184		 */
2185		rtnl_held = true;
2186		/* Replay the request. */
2187		goto replay;
2188	}
2189	return err;
2190
2191errout_locked:
2192	mutex_unlock(&chain->filter_chain_lock);
2193	goto errout;
2194}
2195
2196static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2197			  struct netlink_ext_ack *extack)
2198{
2199	struct net *net = sock_net(skb->sk);
2200	struct nlattr *tca[TCA_MAX + 1];
2201	char name[IFNAMSIZ];
2202	struct tcmsg *t;
2203	u32 protocol;
2204	u32 prio;
2205	u32 parent;
2206	u32 chain_index;
2207	struct Qdisc *q = NULL;
2208	struct tcf_chain_info chain_info;
2209	struct tcf_chain *chain = NULL;
2210	struct tcf_block *block = NULL;
2211	struct tcf_proto *tp = NULL;
2212	unsigned long cl = 0;
2213	void *fh = NULL;
2214	int err;
2215	bool rtnl_held = false;
2216
2217	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2218				     rtm_tca_policy, extack);
2219	if (err < 0)
2220		return err;
 
2221
2222	t = nlmsg_data(n);
2223	protocol = TC_H_MIN(t->tcm_info);
2224	prio = TC_H_MAJ(t->tcm_info);
2225	parent = t->tcm_parent;
2226
2227	if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2228		NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2229		return -ENOENT;
2230	}
2231
2232	/* Find head of filter chain. */
2233
2234	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2235	if (err)
2236		return err;
2237
2238	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2239		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2240		err = -EINVAL;
2241		goto errout;
2242	}
2243	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2244	 * found), qdisc is not unlocked, classifier type is not specified,
2245	 * classifier is not unlocked.
2246	 */
2247	if (!prio ||
2248	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2249	    !tcf_proto_is_unlocked(name)) {
2250		rtnl_held = true;
2251		rtnl_lock();
2252	}
2253
2254	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2255	if (err)
2256		goto errout;
2257
2258	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2259				 extack);
2260	if (IS_ERR(block)) {
2261		err = PTR_ERR(block);
2262		goto errout;
2263	}
2264
2265	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2266	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2267		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2268		err = -EINVAL;
2269		goto errout;
2270	}
2271	chain = tcf_chain_get(block, chain_index, false);
2272	if (!chain) {
2273		/* User requested flush on non-existent chain. Nothing to do,
2274		 * so just return success.
2275		 */
2276		if (prio == 0) {
2277			err = 0;
2278			goto errout;
2279		}
2280		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2281		err = -ENOENT;
2282		goto errout;
2283	}
2284
2285	if (prio == 0) {
2286		tfilter_notify_chain(net, skb, block, q, parent, n,
2287				     chain, RTM_DELTFILTER);
2288		tcf_chain_flush(chain, rtnl_held);
2289		err = 0;
2290		goto errout;
2291	}
2292
2293	mutex_lock(&chain->filter_chain_lock);
2294	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2295			       prio, false);
2296	if (!tp || IS_ERR(tp)) {
2297		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2298		err = tp ? PTR_ERR(tp) : -ENOENT;
2299		goto errout_locked;
2300	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2301		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2302		err = -EINVAL;
2303		goto errout_locked;
2304	} else if (t->tcm_handle == 0) {
2305		tcf_proto_signal_destroying(chain, tp);
2306		tcf_chain_tp_remove(chain, &chain_info, tp);
2307		mutex_unlock(&chain->filter_chain_lock);
2308
2309		tcf_proto_put(tp, rtnl_held, NULL);
2310		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2311			       RTM_DELTFILTER, false, rtnl_held);
2312		err = 0;
2313		goto errout;
2314	}
2315	mutex_unlock(&chain->filter_chain_lock);
2316
2317	fh = tp->ops->get(tp, t->tcm_handle);
2318
2319	if (!fh) {
2320		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2321		err = -ENOENT;
2322	} else {
2323		bool last;
2324
2325		err = tfilter_del_notify(net, skb, n, tp, block,
2326					 q, parent, fh, false, &last,
2327					 rtnl_held, extack);
2328
2329		if (err)
2330			goto errout;
2331		if (last)
2332			tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2333	}
2334
2335errout:
2336	if (chain) {
2337		if (tp && !IS_ERR(tp))
2338			tcf_proto_put(tp, rtnl_held, NULL);
2339		tcf_chain_put(chain);
2340	}
2341	tcf_block_release(q, block, rtnl_held);
2342
2343	if (rtnl_held)
2344		rtnl_unlock();
2345
2346	return err;
2347
2348errout_locked:
2349	mutex_unlock(&chain->filter_chain_lock);
2350	goto errout;
2351}
2352
2353static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2354			  struct netlink_ext_ack *extack)
2355{
2356	struct net *net = sock_net(skb->sk);
2357	struct nlattr *tca[TCA_MAX + 1];
2358	char name[IFNAMSIZ];
2359	struct tcmsg *t;
2360	u32 protocol;
2361	u32 prio;
2362	u32 parent;
2363	u32 chain_index;
2364	struct Qdisc *q = NULL;
2365	struct tcf_chain_info chain_info;
2366	struct tcf_chain *chain = NULL;
2367	struct tcf_block *block = NULL;
2368	struct tcf_proto *tp = NULL;
2369	unsigned long cl = 0;
2370	void *fh = NULL;
2371	int err;
2372	bool rtnl_held = false;
2373
2374	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2375				     rtm_tca_policy, extack);
2376	if (err < 0)
2377		return err;
2378
2379	t = nlmsg_data(n);
2380	protocol = TC_H_MIN(t->tcm_info);
2381	prio = TC_H_MAJ(t->tcm_info);
2382	parent = t->tcm_parent;
2383
2384	if (prio == 0) {
2385		NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2386		return -ENOENT;
2387	}
2388
2389	/* Find head of filter chain. */
2390
2391	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2392	if (err)
2393		return err;
2394
2395	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2396		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2397		err = -EINVAL;
2398		goto errout;
2399	}
2400	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2401	 * unlocked, classifier type is not specified, classifier is not
2402	 * unlocked.
2403	 */
2404	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2405	    !tcf_proto_is_unlocked(name)) {
2406		rtnl_held = true;
2407		rtnl_lock();
2408	}
2409
2410	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2411	if (err)
2412		goto errout;
2413
2414	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2415				 extack);
2416	if (IS_ERR(block)) {
2417		err = PTR_ERR(block);
2418		goto errout;
2419	}
2420
2421	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2422	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2423		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2424		err = -EINVAL;
2425		goto errout;
2426	}
2427	chain = tcf_chain_get(block, chain_index, false);
2428	if (!chain) {
2429		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2430		err = -EINVAL;
2431		goto errout;
2432	}
2433
2434	mutex_lock(&chain->filter_chain_lock);
2435	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2436			       prio, false);
2437	mutex_unlock(&chain->filter_chain_lock);
2438	if (!tp || IS_ERR(tp)) {
2439		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2440		err = tp ? PTR_ERR(tp) : -ENOENT;
2441		goto errout;
2442	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2443		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2444		err = -EINVAL;
2445		goto errout;
2446	}
2447
2448	fh = tp->ops->get(tp, t->tcm_handle);
2449
2450	if (!fh) {
2451		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2452		err = -ENOENT;
2453	} else {
2454		err = tfilter_notify(net, skb, n, tp, block, q, parent,
2455				     fh, RTM_NEWTFILTER, true, rtnl_held);
2456		if (err < 0)
2457			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2458	}
2459
2460	tfilter_put(tp, fh);
2461errout:
2462	if (chain) {
2463		if (tp && !IS_ERR(tp))
2464			tcf_proto_put(tp, rtnl_held, NULL);
2465		tcf_chain_put(chain);
2466	}
2467	tcf_block_release(q, block, rtnl_held);
2468
2469	if (rtnl_held)
2470		rtnl_unlock();
2471
2472	return err;
2473}
2474
2475struct tcf_dump_args {
2476	struct tcf_walker w;
2477	struct sk_buff *skb;
2478	struct netlink_callback *cb;
2479	struct tcf_block *block;
2480	struct Qdisc *q;
2481	u32 parent;
2482	bool terse_dump;
2483};
2484
2485static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2486{
2487	struct tcf_dump_args *a = (void *)arg;
2488	struct net *net = sock_net(a->skb->sk);
2489
2490	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2491			     n, NETLINK_CB(a->cb->skb).portid,
2492			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2493			     RTM_NEWTFILTER, a->terse_dump, true);
2494}
2495
2496static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2497			   struct sk_buff *skb, struct netlink_callback *cb,
2498			   long index_start, long *p_index, bool terse)
2499{
2500	struct net *net = sock_net(skb->sk);
2501	struct tcf_block *block = chain->block;
2502	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2503	struct tcf_proto *tp, *tp_prev;
2504	struct tcf_dump_args arg;
2505
2506	for (tp = __tcf_get_next_proto(chain, NULL);
2507	     tp;
2508	     tp_prev = tp,
2509		     tp = __tcf_get_next_proto(chain, tp),
2510		     tcf_proto_put(tp_prev, true, NULL),
2511		     (*p_index)++) {
2512		if (*p_index < index_start)
2513			continue;
2514		if (TC_H_MAJ(tcm->tcm_info) &&
2515		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
2516			continue;
2517		if (TC_H_MIN(tcm->tcm_info) &&
2518		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
2519			continue;
2520		if (*p_index > index_start)
2521			memset(&cb->args[1], 0,
2522			       sizeof(cb->args) - sizeof(cb->args[0]));
2523		if (cb->args[1] == 0) {
2524			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2525					  NETLINK_CB(cb->skb).portid,
2526					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
2527					  RTM_NEWTFILTER, false, true) <= 0)
2528				goto errout;
 
2529			cb->args[1] = 1;
2530		}
2531		if (!tp->ops->walk)
2532			continue;
2533		arg.w.fn = tcf_node_dump;
2534		arg.skb = skb;
2535		arg.cb = cb;
2536		arg.block = block;
2537		arg.q = q;
2538		arg.parent = parent;
2539		arg.w.stop = 0;
2540		arg.w.skip = cb->args[1] - 1;
2541		arg.w.count = 0;
2542		arg.w.cookie = cb->args[2];
2543		arg.terse_dump = terse;
2544		tp->ops->walk(tp, &arg.w, true);
2545		cb->args[2] = arg.w.cookie;
2546		cb->args[1] = arg.w.count + 1;
2547		if (arg.w.stop)
2548			goto errout;
2549	}
2550	return true;
2551
2552errout:
2553	tcf_proto_put(tp, true, NULL);
2554	return false;
2555}
2556
2557static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = {
2558	[TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE),
2559};
2560
2561/* called with RTNL */
2562static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2563{
2564	struct tcf_chain *chain, *chain_prev;
2565	struct net *net = sock_net(skb->sk);
2566	struct nlattr *tca[TCA_MAX + 1];
2567	struct Qdisc *q = NULL;
2568	struct tcf_block *block;
2569	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2570	bool terse_dump = false;
2571	long index_start;
2572	long index;
2573	u32 parent;
2574	int err;
2575
2576	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2577		return skb->len;
2578
2579	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2580				     tcf_tfilter_dump_policy, cb->extack);
2581	if (err)
2582		return err;
2583
2584	if (tca[TCA_DUMP_FLAGS]) {
2585		struct nla_bitfield32 flags =
2586			nla_get_bitfield32(tca[TCA_DUMP_FLAGS]);
2587
2588		terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE;
2589	}
2590
2591	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2592		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2593		if (!block)
2594			goto out;
2595		/* If we work with block index, q is NULL and parent value
2596		 * will never be used in the following code. The check
2597		 * in tcf_fill_node prevents it. However, compiler does not
2598		 * see that far, so set parent to zero to silence the warning
2599		 * about parent being uninitialized.
2600		 */
2601		parent = 0;
2602	} else {
2603		const struct Qdisc_class_ops *cops;
2604		struct net_device *dev;
2605		unsigned long cl = 0;
2606
2607		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2608		if (!dev)
2609			return skb->len;
2610
2611		parent = tcm->tcm_parent;
2612		if (!parent)
2613			q = rtnl_dereference(dev->qdisc);
2614		else
2615			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2616		if (!q)
2617			goto out;
2618		cops = q->ops->cl_ops;
2619		if (!cops)
2620			goto out;
2621		if (!cops->tcf_block)
2622			goto out;
2623		if (TC_H_MIN(tcm->tcm_parent)) {
2624			cl = cops->find(q, tcm->tcm_parent);
2625			if (cl == 0)
2626				goto out;
2627		}
2628		block = cops->tcf_block(q, cl, NULL);
2629		if (!block)
2630			goto out;
2631		parent = block->classid;
2632		if (tcf_block_shared(block))
2633			q = NULL;
2634	}
2635
2636	index_start = cb->args[0];
2637	index = 0;
2638
2639	for (chain = __tcf_get_next_chain(block, NULL);
2640	     chain;
2641	     chain_prev = chain,
2642		     chain = __tcf_get_next_chain(block, chain),
2643		     tcf_chain_put(chain_prev)) {
2644		if (tca[TCA_CHAIN] &&
2645		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2646			continue;
2647		if (!tcf_chain_dump(chain, q, parent, skb, cb,
2648				    index_start, &index, terse_dump)) {
2649			tcf_chain_put(chain);
2650			err = -EMSGSIZE;
2651			break;
2652		}
2653	}
2654
2655	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2656		tcf_block_refcnt_put(block, true);
2657	cb->args[0] = index;
2658
2659out:
2660	/* If we did no progress, the error (EMSGSIZE) is real */
2661	if (skb->len == 0 && err)
2662		return err;
2663	return skb->len;
2664}
2665
2666static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2667			      void *tmplt_priv, u32 chain_index,
2668			      struct net *net, struct sk_buff *skb,
2669			      struct tcf_block *block,
2670			      u32 portid, u32 seq, u16 flags, int event)
2671{
2672	unsigned char *b = skb_tail_pointer(skb);
2673	const struct tcf_proto_ops *ops;
2674	struct nlmsghdr *nlh;
2675	struct tcmsg *tcm;
2676	void *priv;
2677
2678	ops = tmplt_ops;
2679	priv = tmplt_priv;
2680
2681	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2682	if (!nlh)
2683		goto out_nlmsg_trim;
2684	tcm = nlmsg_data(nlh);
2685	tcm->tcm_family = AF_UNSPEC;
2686	tcm->tcm__pad1 = 0;
2687	tcm->tcm__pad2 = 0;
2688	tcm->tcm_handle = 0;
2689	if (block->q) {
2690		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2691		tcm->tcm_parent = block->q->handle;
2692	} else {
2693		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2694		tcm->tcm_block_index = block->index;
2695	}
2696
2697	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2698		goto nla_put_failure;
2699
2700	if (ops) {
2701		if (nla_put_string(skb, TCA_KIND, ops->kind))
2702			goto nla_put_failure;
2703		if (ops->tmplt_dump(skb, net, priv) < 0)
2704			goto nla_put_failure;
2705	}
2706
2707	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2708	return skb->len;
2709
2710out_nlmsg_trim:
2711nla_put_failure:
2712	nlmsg_trim(skb, b);
2713	return -EMSGSIZE;
2714}
2715
2716static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2717			   u32 seq, u16 flags, int event, bool unicast)
2718{
2719	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2720	struct tcf_block *block = chain->block;
2721	struct net *net = block->net;
2722	struct sk_buff *skb;
2723	int err = 0;
2724
2725	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2726	if (!skb)
2727		return -ENOBUFS;
2728
2729	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2730			       chain->index, net, skb, block, portid,
2731			       seq, flags, event) <= 0) {
2732		kfree_skb(skb);
2733		return -EINVAL;
2734	}
2735
2736	if (unicast)
2737		err = rtnl_unicast(skb, net, portid);
2738	else
2739		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2740				     flags & NLM_F_ECHO);
2741
2742	return err;
2743}
2744
2745static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2746				  void *tmplt_priv, u32 chain_index,
2747				  struct tcf_block *block, struct sk_buff *oskb,
2748				  u32 seq, u16 flags, bool unicast)
2749{
2750	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2751	struct net *net = block->net;
2752	struct sk_buff *skb;
2753
2754	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2755	if (!skb)
2756		return -ENOBUFS;
2757
2758	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2759			       block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2760		kfree_skb(skb);
2761		return -EINVAL;
2762	}
2763
2764	if (unicast)
2765		return rtnl_unicast(skb, net, portid);
2766
2767	return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2768}
2769
2770static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2771			      struct nlattr **tca,
2772			      struct netlink_ext_ack *extack)
2773{
2774	const struct tcf_proto_ops *ops;
2775	char name[IFNAMSIZ];
2776	void *tmplt_priv;
2777
2778	/* If kind is not set, user did not specify template. */
2779	if (!tca[TCA_KIND])
2780		return 0;
2781
2782	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2783		NL_SET_ERR_MSG(extack, "Specified TC chain template name too long");
2784		return -EINVAL;
2785	}
2786
2787	ops = tcf_proto_lookup_ops(name, true, extack);
2788	if (IS_ERR(ops))
2789		return PTR_ERR(ops);
2790	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
2791		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
2792		return -EOPNOTSUPP;
2793	}
2794
2795	tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2796	if (IS_ERR(tmplt_priv)) {
2797		module_put(ops->owner);
2798		return PTR_ERR(tmplt_priv);
2799	}
2800	chain->tmplt_ops = ops;
2801	chain->tmplt_priv = tmplt_priv;
2802	return 0;
2803}
2804
2805static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2806			       void *tmplt_priv)
2807{
2808	/* If template ops are set, no work to do for us. */
2809	if (!tmplt_ops)
2810		return;
2811
2812	tmplt_ops->tmplt_destroy(tmplt_priv);
2813	module_put(tmplt_ops->owner);
2814}
2815
2816/* Add/delete/get a chain */
2817
2818static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2819			struct netlink_ext_ack *extack)
2820{
2821	struct net *net = sock_net(skb->sk);
2822	struct nlattr *tca[TCA_MAX + 1];
2823	struct tcmsg *t;
2824	u32 parent;
2825	u32 chain_index;
2826	struct Qdisc *q;
2827	struct tcf_chain *chain;
2828	struct tcf_block *block;
2829	unsigned long cl;
2830	int err;
2831
2832replay:
2833	q = NULL;
2834	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2835				     rtm_tca_policy, extack);
2836	if (err < 0)
2837		return err;
2838
2839	t = nlmsg_data(n);
2840	parent = t->tcm_parent;
2841	cl = 0;
2842
2843	block = tcf_block_find(net, &q, &parent, &cl,
2844			       t->tcm_ifindex, t->tcm_block_index, extack);
2845	if (IS_ERR(block))
2846		return PTR_ERR(block);
2847
2848	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2849	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2850		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2851		err = -EINVAL;
2852		goto errout_block;
2853	}
2854
2855	mutex_lock(&block->lock);
2856	chain = tcf_chain_lookup(block, chain_index);
2857	if (n->nlmsg_type == RTM_NEWCHAIN) {
2858		if (chain) {
2859			if (tcf_chain_held_by_acts_only(chain)) {
2860				/* The chain exists only because there is
2861				 * some action referencing it.
2862				 */
2863				tcf_chain_hold(chain);
2864			} else {
2865				NL_SET_ERR_MSG(extack, "Filter chain already exists");
2866				err = -EEXIST;
2867				goto errout_block_locked;
2868			}
2869		} else {
2870			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2871				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2872				err = -ENOENT;
2873				goto errout_block_locked;
2874			}
2875			chain = tcf_chain_create(block, chain_index);
2876			if (!chain) {
2877				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2878				err = -ENOMEM;
2879				goto errout_block_locked;
2880			}
2881		}
2882	} else {
2883		if (!chain || tcf_chain_held_by_acts_only(chain)) {
2884			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2885			err = -EINVAL;
2886			goto errout_block_locked;
2887		}
2888		tcf_chain_hold(chain);
2889	}
2890
2891	if (n->nlmsg_type == RTM_NEWCHAIN) {
2892		/* Modifying chain requires holding parent block lock. In case
2893		 * the chain was successfully added, take a reference to the
2894		 * chain. This ensures that an empty chain does not disappear at
2895		 * the end of this function.
2896		 */
2897		tcf_chain_hold(chain);
2898		chain->explicitly_created = true;
2899	}
2900	mutex_unlock(&block->lock);
2901
2902	switch (n->nlmsg_type) {
2903	case RTM_NEWCHAIN:
2904		err = tc_chain_tmplt_add(chain, net, tca, extack);
2905		if (err) {
2906			tcf_chain_put_explicitly_created(chain);
2907			goto errout;
2908		}
2909
2910		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2911				RTM_NEWCHAIN, false);
2912		break;
2913	case RTM_DELCHAIN:
2914		tfilter_notify_chain(net, skb, block, q, parent, n,
2915				     chain, RTM_DELTFILTER);
2916		/* Flush the chain first as the user requested chain removal. */
2917		tcf_chain_flush(chain, true);
2918		/* In case the chain was successfully deleted, put a reference
2919		 * to the chain previously taken during addition.
2920		 */
2921		tcf_chain_put_explicitly_created(chain);
2922		break;
2923	case RTM_GETCHAIN:
2924		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2925				      n->nlmsg_flags, n->nlmsg_type, true);
2926		if (err < 0)
2927			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2928		break;
2929	default:
2930		err = -EOPNOTSUPP;
2931		NL_SET_ERR_MSG(extack, "Unsupported message type");
2932		goto errout;
2933	}
2934
2935errout:
2936	tcf_chain_put(chain);
2937errout_block:
2938	tcf_block_release(q, block, true);
2939	if (err == -EAGAIN)
2940		/* Replay the request. */
2941		goto replay;
2942	return err;
2943
2944errout_block_locked:
2945	mutex_unlock(&block->lock);
2946	goto errout_block;
2947}
2948
2949/* called with RTNL */
2950static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2951{
2952	struct net *net = sock_net(skb->sk);
2953	struct nlattr *tca[TCA_MAX + 1];
2954	struct Qdisc *q = NULL;
2955	struct tcf_block *block;
2956	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2957	struct tcf_chain *chain;
2958	long index_start;
2959	long index;
2960	int err;
2961
2962	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2963		return skb->len;
2964
2965	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2966				     rtm_tca_policy, cb->extack);
2967	if (err)
2968		return err;
2969
2970	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2971		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2972		if (!block)
2973			goto out;
2974	} else {
2975		const struct Qdisc_class_ops *cops;
2976		struct net_device *dev;
2977		unsigned long cl = 0;
2978
2979		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2980		if (!dev)
2981			return skb->len;
2982
2983		if (!tcm->tcm_parent)
2984			q = rtnl_dereference(dev->qdisc);
2985		else
2986			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2987
2988		if (!q)
2989			goto out;
2990		cops = q->ops->cl_ops;
2991		if (!cops)
2992			goto out;
2993		if (!cops->tcf_block)
2994			goto out;
2995		if (TC_H_MIN(tcm->tcm_parent)) {
2996			cl = cops->find(q, tcm->tcm_parent);
2997			if (cl == 0)
2998				goto out;
2999		}
3000		block = cops->tcf_block(q, cl, NULL);
3001		if (!block)
3002			goto out;
3003		if (tcf_block_shared(block))
3004			q = NULL;
3005	}
3006
3007	index_start = cb->args[0];
3008	index = 0;
3009
3010	mutex_lock(&block->lock);
3011	list_for_each_entry(chain, &block->chain_list, list) {
3012		if ((tca[TCA_CHAIN] &&
3013		     nla_get_u32(tca[TCA_CHAIN]) != chain->index))
3014			continue;
3015		if (index < index_start) {
3016			index++;
3017			continue;
3018		}
3019		if (tcf_chain_held_by_acts_only(chain))
3020			continue;
3021		err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
3022					 chain->index, net, skb, block,
3023					 NETLINK_CB(cb->skb).portid,
3024					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
3025					 RTM_NEWCHAIN);
3026		if (err <= 0)
3027			break;
3028		index++;
3029	}
3030	mutex_unlock(&block->lock);
3031
3032	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
3033		tcf_block_refcnt_put(block, true);
3034	cb->args[0] = index;
3035
3036out:
3037	/* If we did no progress, the error (EMSGSIZE) is real */
3038	if (skb->len == 0 && err)
3039		return err;
3040	return skb->len;
3041}
3042
3043void tcf_exts_destroy(struct tcf_exts *exts)
3044{
3045#ifdef CONFIG_NET_CLS_ACT
3046	if (exts->actions) {
3047		tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3048		kfree(exts->actions);
3049	}
3050	exts->nr_actions = 0;
3051#endif
3052}
3053EXPORT_SYMBOL(tcf_exts_destroy);
3054
3055int tcf_exts_validate_ex(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3056			 struct nlattr *rate_tlv, struct tcf_exts *exts,
3057			 u32 flags, u32 fl_flags, struct netlink_ext_ack *extack)
3058{
 
 
3059#ifdef CONFIG_NET_CLS_ACT
3060	{
3061		int init_res[TCA_ACT_MAX_PRIO] = {};
3062		struct tc_action *act;
3063		size_t attr_size = 0;
3064
3065		if (exts->police && tb[exts->police]) {
3066			struct tc_action_ops *a_o;
 
 
 
 
3067
3068			a_o = tc_action_load_ops(tb[exts->police], true,
3069						 !(flags & TCA_ACT_FLAGS_NO_RTNL),
3070						 extack);
3071			if (IS_ERR(a_o))
3072				return PTR_ERR(a_o);
3073			flags |= TCA_ACT_FLAGS_POLICE | TCA_ACT_FLAGS_BIND;
3074			act = tcf_action_init_1(net, tp, tb[exts->police],
3075						rate_tlv, a_o, init_res, flags,
3076						extack);
3077			module_put(a_o->owner);
3078			if (IS_ERR(act))
3079				return PTR_ERR(act);
3080
3081			act->type = exts->type = TCA_OLD_COMPAT;
3082			exts->actions[0] = act;
3083			exts->nr_actions = 1;
3084			tcf_idr_insert_many(exts->actions);
3085		} else if (exts->action && tb[exts->action]) {
3086			int err;
3087
3088			flags |= TCA_ACT_FLAGS_BIND;
3089			err = tcf_action_init(net, tp, tb[exts->action],
3090					      rate_tlv, exts->actions, init_res,
3091					      &attr_size, flags, fl_flags,
3092					      extack);
3093			if (err < 0)
3094				return err;
3095			exts->nr_actions = err;
3096		}
3097	}
3098#else
3099	if ((exts->action && tb[exts->action]) ||
3100	    (exts->police && tb[exts->police])) {
3101		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3102		return -EOPNOTSUPP;
3103	}
3104#endif
3105
3106	return 0;
3107}
3108EXPORT_SYMBOL(tcf_exts_validate_ex);
3109
3110int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3111		      struct nlattr *rate_tlv, struct tcf_exts *exts,
3112		      u32 flags, struct netlink_ext_ack *extack)
3113{
3114	return tcf_exts_validate_ex(net, tp, tb, rate_tlv, exts,
3115				    flags, 0, extack);
3116}
3117EXPORT_SYMBOL(tcf_exts_validate);
3118
3119void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
 
3120{
3121#ifdef CONFIG_NET_CLS_ACT
3122	struct tcf_exts old = *dst;
3123
3124	*dst = *src;
3125	tcf_exts_destroy(&old);
 
 
 
 
 
3126#endif
3127}
3128EXPORT_SYMBOL(tcf_exts_change);
3129
3130#ifdef CONFIG_NET_CLS_ACT
3131static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3132{
3133	if (exts->nr_actions == 0)
3134		return NULL;
3135	else
3136		return exts->actions[0];
3137}
3138#endif
3139
3140int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3141{
3142#ifdef CONFIG_NET_CLS_ACT
3143	struct nlattr *nest;
3144
3145	if (exts->action && tcf_exts_has_actions(exts)) {
3146		/*
3147		 * again for backward compatible mode - we want
3148		 * to work with both old and new modes of entering
3149		 * tc data even if iproute2  was newer - jhs
3150		 */
3151		if (exts->type != TCA_OLD_COMPAT) {
3152			nest = nla_nest_start_noflag(skb, exts->action);
 
 
3153			if (nest == NULL)
3154				goto nla_put_failure;
3155
3156			if (tcf_action_dump(skb, exts->actions, 0, 0, false)
3157			    < 0)
3158				goto nla_put_failure;
3159			nla_nest_end(skb, nest);
3160		} else if (exts->police) {
3161			struct tc_action *act = tcf_exts_first_act(exts);
3162			nest = nla_nest_start_noflag(skb, exts->police);
3163			if (nest == NULL || !act)
3164				goto nla_put_failure;
3165			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3166				goto nla_put_failure;
3167			nla_nest_end(skb, nest);
3168		}
3169	}
 
3170	return 0;
3171
3172nla_put_failure:
3173	nla_nest_cancel(skb, nest);
3174	return -1;
3175#else
3176	return 0;
3177#endif
3178}
3179EXPORT_SYMBOL(tcf_exts_dump);
3180
3181int tcf_exts_terse_dump(struct sk_buff *skb, struct tcf_exts *exts)
3182{
3183#ifdef CONFIG_NET_CLS_ACT
3184	struct nlattr *nest;
3185
3186	if (!exts->action || !tcf_exts_has_actions(exts))
3187		return 0;
3188
3189	nest = nla_nest_start_noflag(skb, exts->action);
3190	if (!nest)
3191		goto nla_put_failure;
3192
3193	if (tcf_action_dump(skb, exts->actions, 0, 0, true) < 0)
3194		goto nla_put_failure;
3195	nla_nest_end(skb, nest);
3196	return 0;
3197
3198nla_put_failure:
3199	nla_nest_cancel(skb, nest);
3200	return -1;
3201#else
3202	return 0;
3203#endif
3204}
3205EXPORT_SYMBOL(tcf_exts_terse_dump);
3206
3207int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3208{
3209#ifdef CONFIG_NET_CLS_ACT
3210	struct tc_action *a = tcf_exts_first_act(exts);
3211	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3212		return -1;
3213#endif
3214	return 0;
 
 
3215}
3216EXPORT_SYMBOL(tcf_exts_dump_stats);
3217
3218static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3219{
3220	if (*flags & TCA_CLS_FLAGS_IN_HW)
3221		return;
3222	*flags |= TCA_CLS_FLAGS_IN_HW;
3223	atomic_inc(&block->offloadcnt);
3224}
3225
3226static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3227{
3228	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3229		return;
3230	*flags &= ~TCA_CLS_FLAGS_IN_HW;
3231	atomic_dec(&block->offloadcnt);
3232}
3233
3234static void tc_cls_offload_cnt_update(struct tcf_block *block,
3235				      struct tcf_proto *tp, u32 *cnt,
3236				      u32 *flags, u32 diff, bool add)
3237{
3238	lockdep_assert_held(&block->cb_lock);
3239
3240	spin_lock(&tp->lock);
3241	if (add) {
3242		if (!*cnt)
3243			tcf_block_offload_inc(block, flags);
3244		*cnt += diff;
3245	} else {
3246		*cnt -= diff;
3247		if (!*cnt)
3248			tcf_block_offload_dec(block, flags);
3249	}
3250	spin_unlock(&tp->lock);
3251}
3252
3253static void
3254tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3255			 u32 *cnt, u32 *flags)
3256{
3257	lockdep_assert_held(&block->cb_lock);
3258
3259	spin_lock(&tp->lock);
3260	tcf_block_offload_dec(block, flags);
3261	*cnt = 0;
3262	spin_unlock(&tp->lock);
3263}
3264
3265static int
3266__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3267		   void *type_data, bool err_stop)
3268{
3269	struct flow_block_cb *block_cb;
3270	int ok_count = 0;
3271	int err;
3272
3273	list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3274		err = block_cb->cb(type, type_data, block_cb->cb_priv);
3275		if (err) {
3276			if (err_stop)
3277				return err;
3278		} else {
3279			ok_count++;
3280		}
3281	}
3282	return ok_count;
3283}
3284
3285int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3286		     void *type_data, bool err_stop, bool rtnl_held)
3287{
3288	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3289	int ok_count;
3290
3291retry:
3292	if (take_rtnl)
3293		rtnl_lock();
3294	down_read(&block->cb_lock);
3295	/* Need to obtain rtnl lock if block is bound to devs that require it.
3296	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3297	 * obtain the locks in same order here.
3298	 */
3299	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3300		up_read(&block->cb_lock);
3301		take_rtnl = true;
3302		goto retry;
3303	}
3304
3305	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3306
3307	up_read(&block->cb_lock);
3308	if (take_rtnl)
3309		rtnl_unlock();
3310	return ok_count;
3311}
3312EXPORT_SYMBOL(tc_setup_cb_call);
3313
3314/* Non-destructive filter add. If filter that wasn't already in hardware is
3315 * successfully offloaded, increment block offloads counter. On failure,
3316 * previously offloaded filter is considered to be intact and offloads counter
3317 * is not decremented.
3318 */
3319
3320int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3321		    enum tc_setup_type type, void *type_data, bool err_stop,
3322		    u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3323{
3324	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3325	int ok_count;
3326
3327retry:
3328	if (take_rtnl)
3329		rtnl_lock();
3330	down_read(&block->cb_lock);
3331	/* Need to obtain rtnl lock if block is bound to devs that require it.
3332	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3333	 * obtain the locks in same order here.
3334	 */
3335	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3336		up_read(&block->cb_lock);
3337		take_rtnl = true;
3338		goto retry;
3339	}
3340
3341	/* Make sure all netdevs sharing this block are offload-capable. */
3342	if (block->nooffloaddevcnt && err_stop) {
3343		ok_count = -EOPNOTSUPP;
3344		goto err_unlock;
3345	}
3346
3347	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3348	if (ok_count < 0)
3349		goto err_unlock;
3350
3351	if (tp->ops->hw_add)
3352		tp->ops->hw_add(tp, type_data);
3353	if (ok_count > 0)
3354		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3355					  ok_count, true);
3356err_unlock:
3357	up_read(&block->cb_lock);
3358	if (take_rtnl)
3359		rtnl_unlock();
3360	return min(ok_count, 0);
3361}
3362EXPORT_SYMBOL(tc_setup_cb_add);
3363
3364/* Destructive filter replace. If filter that wasn't already in hardware is
3365 * successfully offloaded, increment block offload counter. On failure,
3366 * previously offloaded filter is considered to be destroyed and offload counter
3367 * is decremented.
3368 */
3369
3370int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3371			enum tc_setup_type type, void *type_data, bool err_stop,
3372			u32 *old_flags, unsigned int *old_in_hw_count,
3373			u32 *new_flags, unsigned int *new_in_hw_count,
3374			bool rtnl_held)
3375{
3376	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3377	int ok_count;
3378
3379retry:
3380	if (take_rtnl)
3381		rtnl_lock();
3382	down_read(&block->cb_lock);
3383	/* Need to obtain rtnl lock if block is bound to devs that require it.
3384	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3385	 * obtain the locks in same order here.
3386	 */
3387	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3388		up_read(&block->cb_lock);
3389		take_rtnl = true;
3390		goto retry;
3391	}
3392
3393	/* Make sure all netdevs sharing this block are offload-capable. */
3394	if (block->nooffloaddevcnt && err_stop) {
3395		ok_count = -EOPNOTSUPP;
3396		goto err_unlock;
3397	}
3398
3399	tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3400	if (tp->ops->hw_del)
3401		tp->ops->hw_del(tp, type_data);
3402
3403	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3404	if (ok_count < 0)
3405		goto err_unlock;
3406
3407	if (tp->ops->hw_add)
3408		tp->ops->hw_add(tp, type_data);
3409	if (ok_count > 0)
3410		tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3411					  new_flags, ok_count, true);
3412err_unlock:
3413	up_read(&block->cb_lock);
3414	if (take_rtnl)
3415		rtnl_unlock();
3416	return min(ok_count, 0);
3417}
3418EXPORT_SYMBOL(tc_setup_cb_replace);
3419
3420/* Destroy filter and decrement block offload counter, if filter was previously
3421 * offloaded.
3422 */
3423
3424int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3425			enum tc_setup_type type, void *type_data, bool err_stop,
3426			u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3427{
3428	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3429	int ok_count;
3430
3431retry:
3432	if (take_rtnl)
3433		rtnl_lock();
3434	down_read(&block->cb_lock);
3435	/* Need to obtain rtnl lock if block is bound to devs that require it.
3436	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3437	 * obtain the locks in same order here.
3438	 */
3439	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3440		up_read(&block->cb_lock);
3441		take_rtnl = true;
3442		goto retry;
3443	}
3444
3445	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3446
3447	tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3448	if (tp->ops->hw_del)
3449		tp->ops->hw_del(tp, type_data);
3450
3451	up_read(&block->cb_lock);
3452	if (take_rtnl)
3453		rtnl_unlock();
3454	return min(ok_count, 0);
3455}
3456EXPORT_SYMBOL(tc_setup_cb_destroy);
3457
3458int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3459			  bool add, flow_setup_cb_t *cb,
3460			  enum tc_setup_type type, void *type_data,
3461			  void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3462{
3463	int err = cb(type, type_data, cb_priv);
3464
3465	if (err) {
3466		if (add && tc_skip_sw(*flags))
3467			return err;
3468	} else {
3469		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3470					  add);
3471	}
3472
3473	return 0;
3474}
3475EXPORT_SYMBOL(tc_setup_cb_reoffload);
3476
3477static int tcf_act_get_cookie(struct flow_action_entry *entry,
3478			      const struct tc_action *act)
3479{
3480	struct tc_cookie *cookie;
3481	int err = 0;
3482
3483	rcu_read_lock();
3484	cookie = rcu_dereference(act->act_cookie);
3485	if (cookie) {
3486		entry->cookie = flow_action_cookie_create(cookie->data,
3487							  cookie->len,
3488							  GFP_ATOMIC);
3489		if (!entry->cookie)
3490			err = -ENOMEM;
3491	}
3492	rcu_read_unlock();
3493	return err;
3494}
3495
3496static void tcf_act_put_cookie(struct flow_action_entry *entry)
3497{
3498	flow_action_cookie_destroy(entry->cookie);
3499}
3500
3501void tc_cleanup_offload_action(struct flow_action *flow_action)
3502{
3503	struct flow_action_entry *entry;
3504	int i;
3505
3506	flow_action_for_each(i, entry, flow_action) {
3507		tcf_act_put_cookie(entry);
3508		if (entry->destructor)
3509			entry->destructor(entry->destructor_priv);
3510	}
3511}
3512EXPORT_SYMBOL(tc_cleanup_offload_action);
3513
3514static int tc_setup_offload_act(struct tc_action *act,
3515				struct flow_action_entry *entry,
3516				u32 *index_inc,
3517				struct netlink_ext_ack *extack)
3518{
3519#ifdef CONFIG_NET_CLS_ACT
3520	if (act->ops->offload_act_setup) {
3521		return act->ops->offload_act_setup(act, entry, index_inc, true,
3522						   extack);
3523	} else {
3524		NL_SET_ERR_MSG(extack, "Action does not support offload");
3525		return -EOPNOTSUPP;
3526	}
3527#else
3528	return 0;
3529#endif
3530}
3531
3532int tc_setup_action(struct flow_action *flow_action,
3533		    struct tc_action *actions[],
3534		    struct netlink_ext_ack *extack)
3535{
3536	int i, j, k, index, err = 0;
3537	struct tc_action *act;
3538
3539	BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY);
3540	BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE);
3541	BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED);
3542
3543	if (!actions)
3544		return 0;
3545
3546	j = 0;
3547	tcf_act_for_each_action(i, act, actions) {
3548		struct flow_action_entry *entry;
3549
3550		entry = &flow_action->entries[j];
3551		spin_lock_bh(&act->tcfa_lock);
3552		err = tcf_act_get_cookie(entry, act);
3553		if (err)
3554			goto err_out_locked;
3555
3556		index = 0;
3557		err = tc_setup_offload_act(act, entry, &index, extack);
3558		if (err)
3559			goto err_out_locked;
3560
3561		for (k = 0; k < index ; k++) {
3562			entry[k].hw_stats = tc_act_hw_stats(act->hw_stats);
3563			entry[k].hw_index = act->tcfa_index;
3564		}
3565
3566		j += index;
3567
3568		spin_unlock_bh(&act->tcfa_lock);
3569	}
3570
3571err_out:
3572	if (err)
3573		tc_cleanup_offload_action(flow_action);
3574
3575	return err;
3576err_out_locked:
3577	spin_unlock_bh(&act->tcfa_lock);
3578	goto err_out;
3579}
3580
3581int tc_setup_offload_action(struct flow_action *flow_action,
3582			    const struct tcf_exts *exts,
3583			    struct netlink_ext_ack *extack)
3584{
3585#ifdef CONFIG_NET_CLS_ACT
3586	if (!exts)
3587		return 0;
3588
3589	return tc_setup_action(flow_action, exts->actions, extack);
3590#else
3591	return 0;
3592#endif
3593}
3594EXPORT_SYMBOL(tc_setup_offload_action);
3595
3596unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3597{
3598	unsigned int num_acts = 0;
3599	struct tc_action *act;
3600	int i;
3601
3602	tcf_exts_for_each_action(i, act, exts) {
3603		if (is_tcf_pedit(act))
3604			num_acts += tcf_pedit_nkeys(act);
3605		else
3606			num_acts++;
3607	}
3608	return num_acts;
3609}
3610EXPORT_SYMBOL(tcf_exts_num_actions);
3611
3612#ifdef CONFIG_NET_CLS_ACT
3613static int tcf_qevent_parse_block_index(struct nlattr *block_index_attr,
3614					u32 *p_block_index,
3615					struct netlink_ext_ack *extack)
3616{
3617	*p_block_index = nla_get_u32(block_index_attr);
3618	if (!*p_block_index) {
3619		NL_SET_ERR_MSG(extack, "Block number may not be zero");
3620		return -EINVAL;
3621	}
3622
3623	return 0;
3624}
3625
3626int tcf_qevent_init(struct tcf_qevent *qe, struct Qdisc *sch,
3627		    enum flow_block_binder_type binder_type,
3628		    struct nlattr *block_index_attr,
3629		    struct netlink_ext_ack *extack)
3630{
3631	u32 block_index;
3632	int err;
3633
3634	if (!block_index_attr)
3635		return 0;
3636
3637	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3638	if (err)
3639		return err;
3640
3641	qe->info.binder_type = binder_type;
3642	qe->info.chain_head_change = tcf_chain_head_change_dflt;
3643	qe->info.chain_head_change_priv = &qe->filter_chain;
3644	qe->info.block_index = block_index;
3645
3646	return tcf_block_get_ext(&qe->block, sch, &qe->info, extack);
3647}
3648EXPORT_SYMBOL(tcf_qevent_init);
3649
3650void tcf_qevent_destroy(struct tcf_qevent *qe, struct Qdisc *sch)
3651{
3652	if (qe->info.block_index)
3653		tcf_block_put_ext(qe->block, sch, &qe->info);
3654}
3655EXPORT_SYMBOL(tcf_qevent_destroy);
3656
3657int tcf_qevent_validate_change(struct tcf_qevent *qe, struct nlattr *block_index_attr,
3658			       struct netlink_ext_ack *extack)
3659{
3660	u32 block_index;
3661	int err;
3662
3663	if (!block_index_attr)
3664		return 0;
3665
3666	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3667	if (err)
3668		return err;
3669
3670	/* Bounce newly-configured block or change in block. */
3671	if (block_index != qe->info.block_index) {
3672		NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
3673		return -EINVAL;
3674	}
3675
3676	return 0;
3677}
3678EXPORT_SYMBOL(tcf_qevent_validate_change);
3679
3680struct sk_buff *tcf_qevent_handle(struct tcf_qevent *qe, struct Qdisc *sch, struct sk_buff *skb,
3681				  struct sk_buff **to_free, int *ret)
3682{
3683	struct tcf_result cl_res;
3684	struct tcf_proto *fl;
3685
3686	if (!qe->info.block_index)
3687		return skb;
3688
3689	fl = rcu_dereference_bh(qe->filter_chain);
3690
3691	switch (tcf_classify(skb, NULL, fl, &cl_res, false)) {
3692	case TC_ACT_SHOT:
3693		qdisc_qstats_drop(sch);
3694		__qdisc_drop(skb, to_free);
3695		*ret = __NET_XMIT_BYPASS;
3696		return NULL;
3697	case TC_ACT_STOLEN:
3698	case TC_ACT_QUEUED:
3699	case TC_ACT_TRAP:
3700		__qdisc_drop(skb, to_free);
3701		*ret = __NET_XMIT_STOLEN;
3702		return NULL;
3703	case TC_ACT_REDIRECT:
3704		skb_do_redirect(skb);
3705		*ret = __NET_XMIT_STOLEN;
3706		return NULL;
3707	}
3708
3709	return skb;
3710}
3711EXPORT_SYMBOL(tcf_qevent_handle);
3712
3713int tcf_qevent_dump(struct sk_buff *skb, int attr_name, struct tcf_qevent *qe)
3714{
3715	if (!qe->info.block_index)
3716		return 0;
3717	return nla_put_u32(skb, attr_name, qe->info.block_index);
3718}
3719EXPORT_SYMBOL(tcf_qevent_dump);
3720#endif
3721
3722static __net_init int tcf_net_init(struct net *net)
3723{
3724	struct tcf_net *tn = net_generic(net, tcf_net_id);
3725
3726	spin_lock_init(&tn->idr_lock);
3727	idr_init(&tn->idr);
3728	return 0;
3729}
3730
3731static void __net_exit tcf_net_exit(struct net *net)
3732{
3733	struct tcf_net *tn = net_generic(net, tcf_net_id);
3734
3735	idr_destroy(&tn->idr);
3736}
3737
3738static struct pernet_operations tcf_net_ops = {
3739	.init = tcf_net_init,
3740	.exit = tcf_net_exit,
3741	.id   = &tcf_net_id,
3742	.size = sizeof(struct tcf_net),
3743};
3744
3745static int __init tc_filter_init(void)
3746{
3747	int err;
3748
3749	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3750	if (!tc_filter_wq)
3751		return -ENOMEM;
3752
3753	err = register_pernet_subsys(&tcf_net_ops);
3754	if (err)
3755		goto err_register_pernet_subsys;
3756
3757	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3758		      RTNL_FLAG_DOIT_UNLOCKED);
3759	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3760		      RTNL_FLAG_DOIT_UNLOCKED);
3761	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3762		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3763	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3764	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3765	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3766		      tc_dump_chain, 0);
3767
3768	return 0;
3769
3770err_register_pernet_subsys:
3771	destroy_workqueue(tc_filter_wq);
3772	return err;
3773}
3774
3775subsys_initcall(tc_filter_init);