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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);
v5.9
   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
  44extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
  45
  46/* The list of all installed classifier types */
  47static LIST_HEAD(tcf_proto_base);
  48
  49/* Protects list of registered TC modules. It is pure SMP lock. */
  50static DEFINE_RWLOCK(cls_mod_lock);
  51
  52static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
  53{
  54	return jhash_3words(tp->chain->index, tp->prio,
  55			    (__force __u32)tp->protocol, 0);
  56}
  57
  58static void tcf_proto_signal_destroying(struct tcf_chain *chain,
  59					struct tcf_proto *tp)
  60{
  61	struct tcf_block *block = chain->block;
  62
  63	mutex_lock(&block->proto_destroy_lock);
  64	hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
  65		     destroy_obj_hashfn(tp));
  66	mutex_unlock(&block->proto_destroy_lock);
  67}
  68
  69static bool tcf_proto_cmp(const struct tcf_proto *tp1,
  70			  const struct tcf_proto *tp2)
  71{
  72	return tp1->chain->index == tp2->chain->index &&
  73	       tp1->prio == tp2->prio &&
  74	       tp1->protocol == tp2->protocol;
  75}
  76
  77static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
  78					struct tcf_proto *tp)
  79{
  80	u32 hash = destroy_obj_hashfn(tp);
  81	struct tcf_proto *iter;
  82	bool found = false;
  83
  84	rcu_read_lock();
  85	hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
  86				   destroy_ht_node, hash) {
  87		if (tcf_proto_cmp(tp, iter)) {
  88			found = true;
  89			break;
  90		}
  91	}
  92	rcu_read_unlock();
  93
  94	return found;
  95}
  96
  97static void
  98tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
  99{
 100	struct tcf_block *block = chain->block;
 101
 102	mutex_lock(&block->proto_destroy_lock);
 103	if (hash_hashed(&tp->destroy_ht_node))
 104		hash_del_rcu(&tp->destroy_ht_node);
 105	mutex_unlock(&block->proto_destroy_lock);
 106}
 107
 108/* Find classifier type by string name */
 109
 110static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
 111{
 112	const struct tcf_proto_ops *t, *res = NULL;
 113
 114	if (kind) {
 115		read_lock(&cls_mod_lock);
 116		list_for_each_entry(t, &tcf_proto_base, head) {
 117			if (strcmp(kind, t->kind) == 0) {
 118				if (try_module_get(t->owner))
 119					res = t;
 120				break;
 121			}
 122		}
 123		read_unlock(&cls_mod_lock);
 124	}
 125	return res;
 126}
 127
 128static const struct tcf_proto_ops *
 129tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
 130		     struct netlink_ext_ack *extack)
 131{
 132	const struct tcf_proto_ops *ops;
 133
 134	ops = __tcf_proto_lookup_ops(kind);
 135	if (ops)
 136		return ops;
 137#ifdef CONFIG_MODULES
 138	if (rtnl_held)
 139		rtnl_unlock();
 140	request_module("cls_%s", kind);
 141	if (rtnl_held)
 142		rtnl_lock();
 143	ops = __tcf_proto_lookup_ops(kind);
 144	/* We dropped the RTNL semaphore in order to perform
 145	 * the module load. So, even if we succeeded in loading
 146	 * the module we have to replay the request. We indicate
 147	 * this using -EAGAIN.
 148	 */
 149	if (ops) {
 150		module_put(ops->owner);
 151		return ERR_PTR(-EAGAIN);
 152	}
 153#endif
 154	NL_SET_ERR_MSG(extack, "TC classifier not found");
 155	return ERR_PTR(-ENOENT);
 156}
 157
 158/* Register(unregister) new classifier type */
 159
 160int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 161{
 162	struct tcf_proto_ops *t;
 163	int rc = -EEXIST;
 164
 165	write_lock(&cls_mod_lock);
 166	list_for_each_entry(t, &tcf_proto_base, head)
 167		if (!strcmp(ops->kind, t->kind))
 168			goto out;
 169
 170	list_add_tail(&ops->head, &tcf_proto_base);
 
 171	rc = 0;
 172out:
 173	write_unlock(&cls_mod_lock);
 174	return rc;
 175}
 176EXPORT_SYMBOL(register_tcf_proto_ops);
 177
 178static struct workqueue_struct *tc_filter_wq;
 179
 180int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 181{
 182	struct tcf_proto_ops *t;
 183	int rc = -ENOENT;
 184
 185	/* Wait for outstanding call_rcu()s, if any, from a
 186	 * tcf_proto_ops's destroy() handler.
 187	 */
 188	rcu_barrier();
 189	flush_workqueue(tc_filter_wq);
 190
 191	write_lock(&cls_mod_lock);
 192	list_for_each_entry(t, &tcf_proto_base, head) {
 193		if (t == ops) {
 194			list_del(&t->head);
 195			rc = 0;
 196			break;
 197		}
 198	}
 
 
 
 
 199	write_unlock(&cls_mod_lock);
 200	return rc;
 201}
 202EXPORT_SYMBOL(unregister_tcf_proto_ops);
 203
 204bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
 205{
 206	INIT_RCU_WORK(rwork, func);
 207	return queue_rcu_work(tc_filter_wq, rwork);
 208}
 209EXPORT_SYMBOL(tcf_queue_work);
 210
 211/* Select new prio value from the range, managed by kernel. */
 212
 213static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 214{
 215	u32 first = TC_H_MAKE(0xC0000000U, 0U);
 216
 217	if (tp)
 218		first = tp->prio - 1;
 219
 220	return TC_H_MAJ(first);
 221}
 222
 223static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 224{
 225	if (kind)
 226		return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ;
 227	memset(name, 0, IFNAMSIZ);
 228	return false;
 229}
 230
 231static bool tcf_proto_is_unlocked(const char *kind)
 232{
 233	const struct tcf_proto_ops *ops;
 234	bool ret;
 235
 236	if (strlen(kind) == 0)
 237		return false;
 238
 239	ops = tcf_proto_lookup_ops(kind, false, NULL);
 240	/* On error return false to take rtnl lock. Proto lookup/create
 241	 * functions will perform lookup again and properly handle errors.
 242	 */
 243	if (IS_ERR(ops))
 244		return false;
 245
 246	ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
 247	module_put(ops->owner);
 248	return ret;
 249}
 250
 251static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 252					  u32 prio, struct tcf_chain *chain,
 253					  bool rtnl_held,
 254					  struct netlink_ext_ack *extack)
 255{
 
 
 
 
 
 
 
 
 
 
 
 256	struct tcf_proto *tp;
 
 
 
 
 257	int err;
 
 258
 259	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 260	if (!tp)
 261		return ERR_PTR(-ENOBUFS);
 262
 263	tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
 264	if (IS_ERR(tp->ops)) {
 265		err = PTR_ERR(tp->ops);
 266		goto errout;
 267	}
 268	tp->classify = tp->ops->classify;
 269	tp->protocol = protocol;
 270	tp->prio = prio;
 271	tp->chain = chain;
 272	spin_lock_init(&tp->lock);
 273	refcount_set(&tp->refcnt, 1);
 274
 275	err = tp->ops->init(tp);
 276	if (err) {
 277		module_put(tp->ops->owner);
 278		goto errout;
 279	}
 280	return tp;
 281
 282errout:
 283	kfree(tp);
 284	return ERR_PTR(err);
 285}
 286
 287static void tcf_proto_get(struct tcf_proto *tp)
 288{
 289	refcount_inc(&tp->refcnt);
 290}
 291
 292static void tcf_chain_put(struct tcf_chain *chain);
 293
 294static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 295			      bool sig_destroy, struct netlink_ext_ack *extack)
 296{
 297	tp->ops->destroy(tp, rtnl_held, extack);
 298	if (sig_destroy)
 299		tcf_proto_signal_destroyed(tp->chain, tp);
 300	tcf_chain_put(tp->chain);
 301	module_put(tp->ops->owner);
 302	kfree_rcu(tp, rcu);
 303}
 304
 305static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
 306			  struct netlink_ext_ack *extack)
 307{
 308	if (refcount_dec_and_test(&tp->refcnt))
 309		tcf_proto_destroy(tp, rtnl_held, true, extack);
 310}
 311
 312static bool tcf_proto_check_delete(struct tcf_proto *tp)
 313{
 314	if (tp->ops->delete_empty)
 315		return tp->ops->delete_empty(tp);
 316
 317	tp->deleting = true;
 318	return tp->deleting;
 319}
 320
 321static void tcf_proto_mark_delete(struct tcf_proto *tp)
 322{
 323	spin_lock(&tp->lock);
 324	tp->deleting = true;
 325	spin_unlock(&tp->lock);
 326}
 327
 328static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 329{
 330	bool deleting;
 331
 332	spin_lock(&tp->lock);
 333	deleting = tp->deleting;
 334	spin_unlock(&tp->lock);
 335
 336	return deleting;
 337}
 338
 339#define ASSERT_BLOCK_LOCKED(block)					\
 340	lockdep_assert_held(&(block)->lock)
 341
 342struct tcf_filter_chain_list_item {
 343	struct list_head list;
 344	tcf_chain_head_change_t *chain_head_change;
 345	void *chain_head_change_priv;
 346};
 347
 348static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 349					  u32 chain_index)
 350{
 351	struct tcf_chain *chain;
 352
 353	ASSERT_BLOCK_LOCKED(block);
 354
 355	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 356	if (!chain)
 357		return NULL;
 358	list_add_tail_rcu(&chain->list, &block->chain_list);
 359	mutex_init(&chain->filter_chain_lock);
 360	chain->block = block;
 361	chain->index = chain_index;
 362	chain->refcnt = 1;
 363	if (!chain->index)
 364		block->chain0.chain = chain;
 365	return chain;
 366}
 367
 368static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 369				       struct tcf_proto *tp_head)
 370{
 371	if (item->chain_head_change)
 372		item->chain_head_change(tp_head, item->chain_head_change_priv);
 373}
 374
 375static void tcf_chain0_head_change(struct tcf_chain *chain,
 376				   struct tcf_proto *tp_head)
 377{
 378	struct tcf_filter_chain_list_item *item;
 379	struct tcf_block *block = chain->block;
 380
 381	if (chain->index)
 382		return;
 383
 384	mutex_lock(&block->lock);
 385	list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 386		tcf_chain_head_change_item(item, tp_head);
 387	mutex_unlock(&block->lock);
 388}
 389
 390/* Returns true if block can be safely freed. */
 391
 392static bool tcf_chain_detach(struct tcf_chain *chain)
 393{
 394	struct tcf_block *block = chain->block;
 395
 396	ASSERT_BLOCK_LOCKED(block);
 397
 398	list_del_rcu(&chain->list);
 399	if (!chain->index)
 400		block->chain0.chain = NULL;
 401
 402	if (list_empty(&block->chain_list) &&
 403	    refcount_read(&block->refcnt) == 0)
 404		return true;
 405
 406	return false;
 407}
 408
 409static void tcf_block_destroy(struct tcf_block *block)
 410{
 411	mutex_destroy(&block->lock);
 412	mutex_destroy(&block->proto_destroy_lock);
 413	kfree_rcu(block, rcu);
 414}
 415
 416static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 417{
 418	struct tcf_block *block = chain->block;
 419
 420	mutex_destroy(&chain->filter_chain_lock);
 421	kfree_rcu(chain, rcu);
 422	if (free_block)
 423		tcf_block_destroy(block);
 424}
 425
 426static void tcf_chain_hold(struct tcf_chain *chain)
 427{
 428	ASSERT_BLOCK_LOCKED(chain->block);
 429
 430	++chain->refcnt;
 431}
 432
 433static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 434{
 435	ASSERT_BLOCK_LOCKED(chain->block);
 436
 437	/* In case all the references are action references, this
 438	 * chain should not be shown to the user.
 439	 */
 440	return chain->refcnt == chain->action_refcnt;
 441}
 442
 443static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 444					  u32 chain_index)
 445{
 446	struct tcf_chain *chain;
 447
 448	ASSERT_BLOCK_LOCKED(block);
 449
 450	list_for_each_entry(chain, &block->chain_list, list) {
 451		if (chain->index == chain_index)
 452			return chain;
 453	}
 454	return NULL;
 455}
 456
 457#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 458static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
 459					      u32 chain_index)
 460{
 461	struct tcf_chain *chain;
 462
 463	list_for_each_entry_rcu(chain, &block->chain_list, list) {
 464		if (chain->index == chain_index)
 465			return chain;
 466	}
 467	return NULL;
 468}
 469#endif
 470
 471static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 472			   u32 seq, u16 flags, int event, bool unicast);
 473
 474static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 475					 u32 chain_index, bool create,
 476					 bool by_act)
 477{
 478	struct tcf_chain *chain = NULL;
 479	bool is_first_reference;
 480
 481	mutex_lock(&block->lock);
 482	chain = tcf_chain_lookup(block, chain_index);
 483	if (chain) {
 484		tcf_chain_hold(chain);
 485	} else {
 486		if (!create)
 487			goto errout;
 488		chain = tcf_chain_create(block, chain_index);
 489		if (!chain)
 490			goto errout;
 491	}
 492
 493	if (by_act)
 494		++chain->action_refcnt;
 495	is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 496	mutex_unlock(&block->lock);
 497
 498	/* Send notification only in case we got the first
 499	 * non-action reference. Until then, the chain acts only as
 500	 * a placeholder for actions pointing to it and user ought
 501	 * not know about them.
 502	 */
 503	if (is_first_reference && !by_act)
 504		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 505				RTM_NEWCHAIN, false);
 506
 507	return chain;
 508
 509errout:
 510	mutex_unlock(&block->lock);
 511	return chain;
 512}
 513
 514static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 515				       bool create)
 516{
 517	return __tcf_chain_get(block, chain_index, create, false);
 518}
 519
 520struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 521{
 522	return __tcf_chain_get(block, chain_index, true, true);
 523}
 524EXPORT_SYMBOL(tcf_chain_get_by_act);
 525
 526static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 527			       void *tmplt_priv);
 528static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 529				  void *tmplt_priv, u32 chain_index,
 530				  struct tcf_block *block, struct sk_buff *oskb,
 531				  u32 seq, u16 flags, bool unicast);
 532
 533static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 534			    bool explicitly_created)
 535{
 536	struct tcf_block *block = chain->block;
 537	const struct tcf_proto_ops *tmplt_ops;
 538	bool free_block = false;
 539	unsigned int refcnt;
 540	void *tmplt_priv;
 541
 542	mutex_lock(&block->lock);
 543	if (explicitly_created) {
 544		if (!chain->explicitly_created) {
 545			mutex_unlock(&block->lock);
 546			return;
 547		}
 548		chain->explicitly_created = false;
 549	}
 550
 551	if (by_act)
 552		chain->action_refcnt--;
 553
 554	/* tc_chain_notify_delete can't be called while holding block lock.
 555	 * However, when block is unlocked chain can be changed concurrently, so
 556	 * save these to temporary variables.
 557	 */
 558	refcnt = --chain->refcnt;
 559	tmplt_ops = chain->tmplt_ops;
 560	tmplt_priv = chain->tmplt_priv;
 561
 562	/* The last dropped non-action reference will trigger notification. */
 563	if (refcnt - chain->action_refcnt == 0 && !by_act) {
 564		tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
 565				       block, NULL, 0, 0, false);
 566		/* Last reference to chain, no need to lock. */
 567		chain->flushing = false;
 568	}
 569
 570	if (refcnt == 0)
 571		free_block = tcf_chain_detach(chain);
 572	mutex_unlock(&block->lock);
 573
 574	if (refcnt == 0) {
 575		tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 576		tcf_chain_destroy(chain, free_block);
 577	}
 578}
 579
 580static void tcf_chain_put(struct tcf_chain *chain)
 581{
 582	__tcf_chain_put(chain, false, false);
 583}
 584
 585void tcf_chain_put_by_act(struct tcf_chain *chain)
 586{
 587	__tcf_chain_put(chain, true, false);
 588}
 589EXPORT_SYMBOL(tcf_chain_put_by_act);
 590
 591static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 592{
 593	__tcf_chain_put(chain, false, true);
 594}
 595
 596static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 597{
 598	struct tcf_proto *tp, *tp_next;
 599
 600	mutex_lock(&chain->filter_chain_lock);
 601	tp = tcf_chain_dereference(chain->filter_chain, chain);
 602	while (tp) {
 603		tp_next = rcu_dereference_protected(tp->next, 1);
 604		tcf_proto_signal_destroying(chain, tp);
 605		tp = tp_next;
 606	}
 607	tp = tcf_chain_dereference(chain->filter_chain, chain);
 608	RCU_INIT_POINTER(chain->filter_chain, NULL);
 609	tcf_chain0_head_change(chain, NULL);
 610	chain->flushing = true;
 611	mutex_unlock(&chain->filter_chain_lock);
 612
 613	while (tp) {
 614		tp_next = rcu_dereference_protected(tp->next, 1);
 615		tcf_proto_put(tp, rtnl_held, NULL);
 616		tp = tp_next;
 617	}
 618}
 619
 620static int tcf_block_setup(struct tcf_block *block,
 621			   struct flow_block_offload *bo);
 622
 623static void tcf_block_offload_init(struct flow_block_offload *bo,
 624				   struct net_device *dev, struct Qdisc *sch,
 625				   enum flow_block_command command,
 626				   enum flow_block_binder_type binder_type,
 627				   struct flow_block *flow_block,
 628				   bool shared, struct netlink_ext_ack *extack)
 629{
 630	bo->net = dev_net(dev);
 631	bo->command = command;
 632	bo->binder_type = binder_type;
 633	bo->block = flow_block;
 634	bo->block_shared = shared;
 635	bo->extack = extack;
 636	bo->sch = sch;
 637	INIT_LIST_HEAD(&bo->cb_list);
 638}
 639
 640static void tcf_block_unbind(struct tcf_block *block,
 641			     struct flow_block_offload *bo);
 642
 643static void tc_block_indr_cleanup(struct flow_block_cb *block_cb)
 644{
 645	struct tcf_block *block = block_cb->indr.data;
 646	struct net_device *dev = block_cb->indr.dev;
 647	struct Qdisc *sch = block_cb->indr.sch;
 648	struct netlink_ext_ack extack = {};
 649	struct flow_block_offload bo;
 650
 651	tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND,
 652			       block_cb->indr.binder_type,
 653			       &block->flow_block, tcf_block_shared(block),
 654			       &extack);
 655	down_write(&block->cb_lock);
 656	list_del(&block_cb->driver_list);
 657	list_move(&block_cb->list, &bo.cb_list);
 658	up_write(&block->cb_lock);
 659	rtnl_lock();
 660	tcf_block_unbind(block, &bo);
 661	rtnl_unlock();
 662}
 663
 664static bool tcf_block_offload_in_use(struct tcf_block *block)
 665{
 666	return atomic_read(&block->offloadcnt);
 667}
 668
 669static int tcf_block_offload_cmd(struct tcf_block *block,
 670				 struct net_device *dev, struct Qdisc *sch,
 671				 struct tcf_block_ext_info *ei,
 672				 enum flow_block_command command,
 673				 struct netlink_ext_ack *extack)
 674{
 675	struct flow_block_offload bo = {};
 676
 677	tcf_block_offload_init(&bo, dev, sch, command, ei->binder_type,
 678			       &block->flow_block, tcf_block_shared(block),
 679			       extack);
 680
 681	if (dev->netdev_ops->ndo_setup_tc) {
 682		int err;
 683
 684		err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 685		if (err < 0) {
 686			if (err != -EOPNOTSUPP)
 687				NL_SET_ERR_MSG(extack, "Driver ndo_setup_tc failed");
 688			return err;
 689		}
 690
 691		return tcf_block_setup(block, &bo);
 692	}
 693
 694	flow_indr_dev_setup_offload(dev, sch, TC_SETUP_BLOCK, block, &bo,
 695				    tc_block_indr_cleanup);
 696	tcf_block_setup(block, &bo);
 697
 698	return -EOPNOTSUPP;
 699}
 700
 701static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 702				  struct tcf_block_ext_info *ei,
 703				  struct netlink_ext_ack *extack)
 704{
 705	struct net_device *dev = q->dev_queue->dev;
 706	int err;
 707
 708	down_write(&block->cb_lock);
 709
 710	/* If tc offload feature is disabled and the block we try to bind
 711	 * to already has some offloaded filters, forbid to bind.
 712	 */
 713	if (dev->netdev_ops->ndo_setup_tc &&
 714	    !tc_can_offload(dev) &&
 715	    tcf_block_offload_in_use(block)) {
 716		NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 717		err = -EOPNOTSUPP;
 718		goto err_unlock;
 719	}
 720
 721	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_BIND, extack);
 722	if (err == -EOPNOTSUPP)
 723		goto no_offload_dev_inc;
 724	if (err)
 725		goto err_unlock;
 726
 727	up_write(&block->cb_lock);
 728	return 0;
 729
 730no_offload_dev_inc:
 731	if (tcf_block_offload_in_use(block))
 732		goto err_unlock;
 733
 734	err = 0;
 735	block->nooffloaddevcnt++;
 736err_unlock:
 737	up_write(&block->cb_lock);
 738	return err;
 739}
 740
 741static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 742				     struct tcf_block_ext_info *ei)
 743{
 744	struct net_device *dev = q->dev_queue->dev;
 745	int err;
 746
 747	down_write(&block->cb_lock);
 748	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_UNBIND, NULL);
 749	if (err == -EOPNOTSUPP)
 750		goto no_offload_dev_dec;
 751	up_write(&block->cb_lock);
 752	return;
 753
 754no_offload_dev_dec:
 755	WARN_ON(block->nooffloaddevcnt-- == 0);
 756	up_write(&block->cb_lock);
 757}
 758
 759static int
 760tcf_chain0_head_change_cb_add(struct tcf_block *block,
 761			      struct tcf_block_ext_info *ei,
 762			      struct netlink_ext_ack *extack)
 763{
 764	struct tcf_filter_chain_list_item *item;
 765	struct tcf_chain *chain0;
 766
 767	item = kmalloc(sizeof(*item), GFP_KERNEL);
 768	if (!item) {
 769		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 770		return -ENOMEM;
 771	}
 772	item->chain_head_change = ei->chain_head_change;
 773	item->chain_head_change_priv = ei->chain_head_change_priv;
 774
 775	mutex_lock(&block->lock);
 776	chain0 = block->chain0.chain;
 777	if (chain0)
 778		tcf_chain_hold(chain0);
 779	else
 780		list_add(&item->list, &block->chain0.filter_chain_list);
 781	mutex_unlock(&block->lock);
 782
 783	if (chain0) {
 784		struct tcf_proto *tp_head;
 785
 786		mutex_lock(&chain0->filter_chain_lock);
 787
 788		tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 789		if (tp_head)
 790			tcf_chain_head_change_item(item, tp_head);
 791
 792		mutex_lock(&block->lock);
 793		list_add(&item->list, &block->chain0.filter_chain_list);
 794		mutex_unlock(&block->lock);
 795
 796		mutex_unlock(&chain0->filter_chain_lock);
 797		tcf_chain_put(chain0);
 798	}
 799
 800	return 0;
 801}
 802
 803static void
 804tcf_chain0_head_change_cb_del(struct tcf_block *block,
 805			      struct tcf_block_ext_info *ei)
 806{
 807	struct tcf_filter_chain_list_item *item;
 808
 809	mutex_lock(&block->lock);
 810	list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 811		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 812		    (item->chain_head_change == ei->chain_head_change &&
 813		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 814			if (block->chain0.chain)
 815				tcf_chain_head_change_item(item, NULL);
 816			list_del(&item->list);
 817			mutex_unlock(&block->lock);
 818
 819			kfree(item);
 820			return;
 821		}
 822	}
 823	mutex_unlock(&block->lock);
 824	WARN_ON(1);
 825}
 826
 827struct tcf_net {
 828	spinlock_t idr_lock; /* Protects idr */
 829	struct idr idr;
 830};
 831
 832static unsigned int tcf_net_id;
 833
 834static int tcf_block_insert(struct tcf_block *block, struct net *net,
 835			    struct netlink_ext_ack *extack)
 836{
 837	struct tcf_net *tn = net_generic(net, tcf_net_id);
 838	int err;
 839
 840	idr_preload(GFP_KERNEL);
 841	spin_lock(&tn->idr_lock);
 842	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 843			    GFP_NOWAIT);
 844	spin_unlock(&tn->idr_lock);
 845	idr_preload_end();
 846
 847	return err;
 848}
 849
 850static void tcf_block_remove(struct tcf_block *block, struct net *net)
 851{
 852	struct tcf_net *tn = net_generic(net, tcf_net_id);
 853
 854	spin_lock(&tn->idr_lock);
 855	idr_remove(&tn->idr, block->index);
 856	spin_unlock(&tn->idr_lock);
 857}
 858
 859static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 860					  u32 block_index,
 861					  struct netlink_ext_ack *extack)
 862{
 863	struct tcf_block *block;
 864
 865	block = kzalloc(sizeof(*block), GFP_KERNEL);
 866	if (!block) {
 867		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 868		return ERR_PTR(-ENOMEM);
 869	}
 870	mutex_init(&block->lock);
 871	mutex_init(&block->proto_destroy_lock);
 872	init_rwsem(&block->cb_lock);
 873	flow_block_init(&block->flow_block);
 874	INIT_LIST_HEAD(&block->chain_list);
 875	INIT_LIST_HEAD(&block->owner_list);
 876	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 877
 878	refcount_set(&block->refcnt, 1);
 879	block->net = net;
 880	block->index = block_index;
 881
 882	/* Don't store q pointer for blocks which are shared */
 883	if (!tcf_block_shared(block))
 884		block->q = q;
 885	return block;
 886}
 887
 888static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 889{
 890	struct tcf_net *tn = net_generic(net, tcf_net_id);
 891
 892	return idr_find(&tn->idr, block_index);
 893}
 894
 895static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
 896{
 897	struct tcf_block *block;
 898
 899	rcu_read_lock();
 900	block = tcf_block_lookup(net, block_index);
 901	if (block && !refcount_inc_not_zero(&block->refcnt))
 902		block = NULL;
 903	rcu_read_unlock();
 904
 905	return block;
 906}
 907
 908static struct tcf_chain *
 909__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 910{
 911	mutex_lock(&block->lock);
 912	if (chain)
 913		chain = list_is_last(&chain->list, &block->chain_list) ?
 914			NULL : list_next_entry(chain, list);
 915	else
 916		chain = list_first_entry_or_null(&block->chain_list,
 917						 struct tcf_chain, list);
 918
 919	/* skip all action-only chains */
 920	while (chain && tcf_chain_held_by_acts_only(chain))
 921		chain = list_is_last(&chain->list, &block->chain_list) ?
 922			NULL : list_next_entry(chain, list);
 923
 924	if (chain)
 925		tcf_chain_hold(chain);
 926	mutex_unlock(&block->lock);
 927
 928	return chain;
 929}
 930
 931/* Function to be used by all clients that want to iterate over all chains on
 932 * block. It properly obtains block->lock and takes reference to chain before
 933 * returning it. Users of this function must be tolerant to concurrent chain
 934 * insertion/deletion or ensure that no concurrent chain modification is
 935 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 936 * consistent dump because rtnl lock is released each time skb is filled with
 937 * data and sent to user-space.
 938 */
 939
 940struct tcf_chain *
 941tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 942{
 943	struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
 944
 945	if (chain)
 946		tcf_chain_put(chain);
 947
 948	return chain_next;
 949}
 950EXPORT_SYMBOL(tcf_get_next_chain);
 951
 952static struct tcf_proto *
 953__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 954{
 955	u32 prio = 0;
 956
 957	ASSERT_RTNL();
 958	mutex_lock(&chain->filter_chain_lock);
 959
 960	if (!tp) {
 961		tp = tcf_chain_dereference(chain->filter_chain, chain);
 962	} else if (tcf_proto_is_deleting(tp)) {
 963		/* 'deleting' flag is set and chain->filter_chain_lock was
 964		 * unlocked, which means next pointer could be invalid. Restart
 965		 * search.
 966		 */
 967		prio = tp->prio + 1;
 968		tp = tcf_chain_dereference(chain->filter_chain, chain);
 969
 970		for (; tp; tp = tcf_chain_dereference(tp->next, chain))
 971			if (!tp->deleting && tp->prio >= prio)
 972				break;
 973	} else {
 974		tp = tcf_chain_dereference(tp->next, chain);
 975	}
 976
 977	if (tp)
 978		tcf_proto_get(tp);
 979
 980	mutex_unlock(&chain->filter_chain_lock);
 981
 982	return tp;
 983}
 984
 985/* Function to be used by all clients that want to iterate over all tp's on
 986 * chain. Users of this function must be tolerant to concurrent tp
 987 * insertion/deletion or ensure that no concurrent chain modification is
 988 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 989 * consistent dump because rtnl lock is released each time skb is filled with
 990 * data and sent to user-space.
 991 */
 992
 993struct tcf_proto *
 994tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp,
 995		   bool rtnl_held)
 996{
 997	struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
 998
 999	if (tp)
1000		tcf_proto_put(tp, rtnl_held, NULL);
1001
1002	return tp_next;
1003}
1004EXPORT_SYMBOL(tcf_get_next_proto);
1005
1006static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1007{
1008	struct tcf_chain *chain;
1009
1010	/* Last reference to block. At this point chains cannot be added or
1011	 * removed concurrently.
1012	 */
1013	for (chain = tcf_get_next_chain(block, NULL);
1014	     chain;
1015	     chain = tcf_get_next_chain(block, chain)) {
1016		tcf_chain_put_explicitly_created(chain);
1017		tcf_chain_flush(chain, rtnl_held);
1018	}
1019}
1020
1021/* Lookup Qdisc and increments its reference counter.
1022 * Set parent, if necessary.
1023 */
1024
1025static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1026			    u32 *parent, int ifindex, bool rtnl_held,
1027			    struct netlink_ext_ack *extack)
1028{
1029	const struct Qdisc_class_ops *cops;
1030	struct net_device *dev;
1031	int err = 0;
1032
1033	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1034		return 0;
1035
1036	rcu_read_lock();
1037
1038	/* Find link */
1039	dev = dev_get_by_index_rcu(net, ifindex);
1040	if (!dev) {
1041		rcu_read_unlock();
1042		return -ENODEV;
1043	}
 
 
 
1044
1045	/* Find qdisc */
1046	if (!*parent) {
1047		*q = dev->qdisc;
1048		*parent = (*q)->handle;
1049	} else {
1050		*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1051		if (!*q) {
1052			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1053			err = -EINVAL;
1054			goto errout_rcu;
1055		}
1056	}
1057
1058	*q = qdisc_refcount_inc_nz(*q);
1059	if (!*q) {
1060		NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1061		err = -EINVAL;
1062		goto errout_rcu;
1063	}
1064
1065	/* Is it classful? */
1066	cops = (*q)->ops->cl_ops;
1067	if (!cops) {
1068		NL_SET_ERR_MSG(extack, "Qdisc not classful");
1069		err = -EINVAL;
1070		goto errout_qdisc;
1071	}
1072
1073	if (!cops->tcf_block) {
1074		NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1075		err = -EOPNOTSUPP;
1076		goto errout_qdisc;
1077	}
1078
1079errout_rcu:
1080	/* At this point we know that qdisc is not noop_qdisc,
1081	 * which means that qdisc holds a reference to net_device
1082	 * and we hold a reference to qdisc, so it is safe to release
1083	 * rcu read lock.
1084	 */
1085	rcu_read_unlock();
1086	return err;
1087
1088errout_qdisc:
1089	rcu_read_unlock();
1090
1091	if (rtnl_held)
1092		qdisc_put(*q);
1093	else
1094		qdisc_put_unlocked(*q);
1095	*q = NULL;
1096
1097	return err;
1098}
1099
1100static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1101			       int ifindex, struct netlink_ext_ack *extack)
1102{
1103	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1104		return 0;
1105
1106	/* Do we search for filter, attached to class? */
1107	if (TC_H_MIN(parent)) {
1108		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1109
1110		*cl = cops->find(q, parent);
1111		if (*cl == 0) {
1112			NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1113			return -ENOENT;
1114		}
1115	}
1116
1117	return 0;
1118}
1119
1120static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1121					  unsigned long cl, int ifindex,
1122					  u32 block_index,
1123					  struct netlink_ext_ack *extack)
1124{
1125	struct tcf_block *block;
1126
1127	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1128		block = tcf_block_refcnt_get(net, block_index);
1129		if (!block) {
1130			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1131			return ERR_PTR(-EINVAL);
1132		}
1133	} else {
1134		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1135
1136		block = cops->tcf_block(q, cl, extack);
1137		if (!block)
1138			return ERR_PTR(-EINVAL);
1139
1140		if (tcf_block_shared(block)) {
1141			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1142			return ERR_PTR(-EOPNOTSUPP);
1143		}
1144
1145		/* Always take reference to block in order to support execution
1146		 * of rules update path of cls API without rtnl lock. Caller
1147		 * must release block when it is finished using it. 'if' block
1148		 * of this conditional obtain reference to block by calling
1149		 * tcf_block_refcnt_get().
1150		 */
1151		refcount_inc(&block->refcnt);
1152	}
1153
1154	return block;
1155}
1156
1157static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1158			    struct tcf_block_ext_info *ei, bool rtnl_held)
1159{
1160	if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1161		/* Flushing/putting all chains will cause the block to be
1162		 * deallocated when last chain is freed. However, if chain_list
1163		 * is empty, block has to be manually deallocated. After block
1164		 * reference counter reached 0, it is no longer possible to
1165		 * increment it or add new chains to block.
1166		 */
1167		bool free_block = list_empty(&block->chain_list);
1168
1169		mutex_unlock(&block->lock);
1170		if (tcf_block_shared(block))
1171			tcf_block_remove(block, block->net);
1172
1173		if (q)
1174			tcf_block_offload_unbind(block, q, ei);
1175
1176		if (free_block)
1177			tcf_block_destroy(block);
1178		else
1179			tcf_block_flush_all_chains(block, rtnl_held);
1180	} else if (q) {
1181		tcf_block_offload_unbind(block, q, ei);
1182	}
1183}
1184
1185static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1186{
1187	__tcf_block_put(block, NULL, NULL, rtnl_held);
1188}
1189
1190/* Find tcf block.
1191 * Set q, parent, cl when appropriate.
1192 */
1193
1194static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1195					u32 *parent, unsigned long *cl,
1196					int ifindex, u32 block_index,
1197					struct netlink_ext_ack *extack)
1198{
1199	struct tcf_block *block;
1200	int err = 0;
1201
1202	ASSERT_RTNL();
1203
1204	err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1205	if (err)
1206		goto errout;
1207
1208	err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1209	if (err)
1210		goto errout_qdisc;
1211
1212	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1213	if (IS_ERR(block)) {
1214		err = PTR_ERR(block);
1215		goto errout_qdisc;
1216	}
1217
1218	return block;
1219
1220errout_qdisc:
1221	if (*q)
1222		qdisc_put(*q);
1223errout:
1224	*q = NULL;
1225	return ERR_PTR(err);
1226}
1227
1228static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1229			      bool rtnl_held)
1230{
1231	if (!IS_ERR_OR_NULL(block))
1232		tcf_block_refcnt_put(block, rtnl_held);
1233
1234	if (q) {
1235		if (rtnl_held)
1236			qdisc_put(q);
1237		else
1238			qdisc_put_unlocked(q);
1239	}
1240}
1241
1242struct tcf_block_owner_item {
1243	struct list_head list;
1244	struct Qdisc *q;
1245	enum flow_block_binder_type binder_type;
1246};
1247
1248static void
1249tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1250			       struct Qdisc *q,
1251			       enum flow_block_binder_type binder_type)
1252{
1253	if (block->keep_dst &&
1254	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1255	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1256		netif_keep_dst(qdisc_dev(q));
1257}
1258
1259void tcf_block_netif_keep_dst(struct tcf_block *block)
1260{
1261	struct tcf_block_owner_item *item;
1262
1263	block->keep_dst = true;
1264	list_for_each_entry(item, &block->owner_list, list)
1265		tcf_block_owner_netif_keep_dst(block, item->q,
1266					       item->binder_type);
1267}
1268EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1269
1270static int tcf_block_owner_add(struct tcf_block *block,
1271			       struct Qdisc *q,
1272			       enum flow_block_binder_type binder_type)
1273{
1274	struct tcf_block_owner_item *item;
1275
1276	item = kmalloc(sizeof(*item), GFP_KERNEL);
1277	if (!item)
1278		return -ENOMEM;
1279	item->q = q;
1280	item->binder_type = binder_type;
1281	list_add(&item->list, &block->owner_list);
1282	return 0;
1283}
1284
1285static void tcf_block_owner_del(struct tcf_block *block,
1286				struct Qdisc *q,
1287				enum flow_block_binder_type binder_type)
1288{
1289	struct tcf_block_owner_item *item;
1290
1291	list_for_each_entry(item, &block->owner_list, list) {
1292		if (item->q == q && item->binder_type == binder_type) {
1293			list_del(&item->list);
1294			kfree(item);
1295			return;
1296		}
1297	}
1298	WARN_ON(1);
1299}
1300
1301int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1302		      struct tcf_block_ext_info *ei,
1303		      struct netlink_ext_ack *extack)
1304{
1305	struct net *net = qdisc_net(q);
1306	struct tcf_block *block = NULL;
1307	int err;
1308
1309	if (ei->block_index)
1310		/* block_index not 0 means the shared block is requested */
1311		block = tcf_block_refcnt_get(net, ei->block_index);
1312
1313	if (!block) {
1314		block = tcf_block_create(net, q, ei->block_index, extack);
1315		if (IS_ERR(block))
1316			return PTR_ERR(block);
1317		if (tcf_block_shared(block)) {
1318			err = tcf_block_insert(block, net, extack);
1319			if (err)
1320				goto err_block_insert;
1321		}
1322	}
1323
1324	err = tcf_block_owner_add(block, q, ei->binder_type);
1325	if (err)
1326		goto err_block_owner_add;
1327
1328	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
 
 
 
1329
1330	err = tcf_chain0_head_change_cb_add(block, ei, extack);
1331	if (err)
1332		goto err_chain0_head_change_cb_add;
1333
1334	err = tcf_block_offload_bind(block, q, ei, extack);
1335	if (err)
1336		goto err_block_offload_bind;
1337
1338	*p_block = block;
1339	return 0;
 
 
 
 
 
 
 
 
1340
1341err_block_offload_bind:
1342	tcf_chain0_head_change_cb_del(block, ei);
1343err_chain0_head_change_cb_add:
1344	tcf_block_owner_del(block, q, ei->binder_type);
1345err_block_owner_add:
1346err_block_insert:
1347	tcf_block_refcnt_put(block, true);
1348	return err;
1349}
1350EXPORT_SYMBOL(tcf_block_get_ext);
1351
1352static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1353{
1354	struct tcf_proto __rcu **p_filter_chain = priv;
1355
1356	rcu_assign_pointer(*p_filter_chain, tp_head);
1357}
1358
1359int tcf_block_get(struct tcf_block **p_block,
1360		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1361		  struct netlink_ext_ack *extack)
1362{
1363	struct tcf_block_ext_info ei = {
1364		.chain_head_change = tcf_chain_head_change_dflt,
1365		.chain_head_change_priv = p_filter_chain,
1366	};
1367
1368	WARN_ON(!p_filter_chain);
1369	return tcf_block_get_ext(p_block, q, &ei, extack);
1370}
1371EXPORT_SYMBOL(tcf_block_get);
1372
1373/* XXX: Standalone actions are not allowed to jump to any chain, and bound
1374 * actions should be all removed after flushing.
1375 */
1376void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1377		       struct tcf_block_ext_info *ei)
1378{
1379	if (!block)
1380		return;
1381	tcf_chain0_head_change_cb_del(block, ei);
1382	tcf_block_owner_del(block, q, ei->binder_type);
1383
1384	__tcf_block_put(block, q, ei, true);
1385}
1386EXPORT_SYMBOL(tcf_block_put_ext);
1387
1388void tcf_block_put(struct tcf_block *block)
1389{
1390	struct tcf_block_ext_info ei = {0, };
1391
1392	if (!block)
1393		return;
1394	tcf_block_put_ext(block, block->q, &ei);
1395}
1396
1397EXPORT_SYMBOL(tcf_block_put);
1398
1399static int
1400tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1401			    void *cb_priv, bool add, bool offload_in_use,
1402			    struct netlink_ext_ack *extack)
1403{
1404	struct tcf_chain *chain, *chain_prev;
1405	struct tcf_proto *tp, *tp_prev;
1406	int err;
1407
1408	lockdep_assert_held(&block->cb_lock);
1409
1410	for (chain = __tcf_get_next_chain(block, NULL);
1411	     chain;
1412	     chain_prev = chain,
1413		     chain = __tcf_get_next_chain(block, chain),
1414		     tcf_chain_put(chain_prev)) {
1415		for (tp = __tcf_get_next_proto(chain, NULL); tp;
1416		     tp_prev = tp,
1417			     tp = __tcf_get_next_proto(chain, tp),
1418			     tcf_proto_put(tp_prev, true, NULL)) {
1419			if (tp->ops->reoffload) {
1420				err = tp->ops->reoffload(tp, add, cb, cb_priv,
1421							 extack);
1422				if (err && add)
1423					goto err_playback_remove;
1424			} else if (add && offload_in_use) {
1425				err = -EOPNOTSUPP;
1426				NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1427				goto err_playback_remove;
1428			}
 
 
 
1429		}
1430	}
1431
1432	return 0;
1433
1434err_playback_remove:
1435	tcf_proto_put(tp, true, NULL);
1436	tcf_chain_put(chain);
1437	tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1438				    extack);
1439	return err;
1440}
1441
1442static int tcf_block_bind(struct tcf_block *block,
1443			  struct flow_block_offload *bo)
1444{
1445	struct flow_block_cb *block_cb, *next;
1446	int err, i = 0;
1447
1448	lockdep_assert_held(&block->cb_lock);
1449
1450	list_for_each_entry(block_cb, &bo->cb_list, list) {
1451		err = tcf_block_playback_offloads(block, block_cb->cb,
1452						  block_cb->cb_priv, true,
1453						  tcf_block_offload_in_use(block),
1454						  bo->extack);
1455		if (err)
1456			goto err_unroll;
1457		if (!bo->unlocked_driver_cb)
1458			block->lockeddevcnt++;
1459
1460		i++;
1461	}
1462	list_splice(&bo->cb_list, &block->flow_block.cb_list);
1463
1464	return 0;
1465
1466err_unroll:
1467	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1468		if (i-- > 0) {
1469			list_del(&block_cb->list);
1470			tcf_block_playback_offloads(block, block_cb->cb,
1471						    block_cb->cb_priv, false,
1472						    tcf_block_offload_in_use(block),
1473						    NULL);
1474			if (!bo->unlocked_driver_cb)
1475				block->lockeddevcnt--;
1476		}
1477		flow_block_cb_free(block_cb);
1478	}
1479
1480	return err;
1481}
1482
1483static void tcf_block_unbind(struct tcf_block *block,
1484			     struct flow_block_offload *bo)
1485{
1486	struct flow_block_cb *block_cb, *next;
1487
1488	lockdep_assert_held(&block->cb_lock);
1489
1490	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1491		tcf_block_playback_offloads(block, block_cb->cb,
1492					    block_cb->cb_priv, false,
1493					    tcf_block_offload_in_use(block),
1494					    NULL);
1495		list_del(&block_cb->list);
1496		flow_block_cb_free(block_cb);
1497		if (!bo->unlocked_driver_cb)
1498			block->lockeddevcnt--;
1499	}
1500}
1501
1502static int tcf_block_setup(struct tcf_block *block,
1503			   struct flow_block_offload *bo)
1504{
1505	int err;
 
1506
1507	switch (bo->command) {
1508	case FLOW_BLOCK_BIND:
1509		err = tcf_block_bind(block, bo);
1510		break;
1511	case FLOW_BLOCK_UNBIND:
1512		err = 0;
1513		tcf_block_unbind(block, bo);
1514		break;
1515	default:
1516		WARN_ON_ONCE(1);
1517		err = -EOPNOTSUPP;
1518	}
1519
1520	return err;
1521}
1522
1523/* Main classifier routine: scans classifier chain attached
1524 * to this qdisc, (optionally) tests for protocol and asks
1525 * specific classifiers.
1526 */
1527static inline int __tcf_classify(struct sk_buff *skb,
1528				 const struct tcf_proto *tp,
1529				 const struct tcf_proto *orig_tp,
1530				 struct tcf_result *res,
1531				 bool compat_mode,
1532				 u32 *last_executed_chain)
1533{
1534#ifdef CONFIG_NET_CLS_ACT
1535	const int max_reclassify_loop = 4;
1536	const struct tcf_proto *first_tp;
1537	int limit = 0;
1538
1539reclassify:
1540#endif
1541	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1542		__be16 protocol = skb_protocol(skb, false);
1543		int err;
1544
1545		if (tp->protocol != protocol &&
1546		    tp->protocol != htons(ETH_P_ALL))
1547			continue;
1548
1549		err = tp->classify(skb, tp, res);
1550#ifdef CONFIG_NET_CLS_ACT
1551		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1552			first_tp = orig_tp;
1553			*last_executed_chain = first_tp->chain->index;
1554			goto reset;
1555		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1556			first_tp = res->goto_tp;
1557			*last_executed_chain = err & TC_ACT_EXT_VAL_MASK;
1558			goto reset;
1559		}
1560#endif
1561		if (err >= 0)
1562			return err;
1563	}
1564
1565	return TC_ACT_UNSPEC; /* signal: continue lookup */
1566#ifdef CONFIG_NET_CLS_ACT
1567reset:
1568	if (unlikely(limit++ >= max_reclassify_loop)) {
1569		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1570				       tp->chain->block->index,
1571				       tp->prio & 0xffff,
1572				       ntohs(tp->protocol));
1573		return TC_ACT_SHOT;
1574	}
1575
1576	tp = first_tp;
1577	goto reclassify;
1578#endif
1579}
1580
1581int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1582		 struct tcf_result *res, bool compat_mode)
1583{
1584	u32 last_executed_chain = 0;
1585
1586	return __tcf_classify(skb, tp, tp, res, compat_mode,
1587			      &last_executed_chain);
1588}
1589EXPORT_SYMBOL(tcf_classify);
1590
1591int tcf_classify_ingress(struct sk_buff *skb,
1592			 const struct tcf_block *ingress_block,
1593			 const struct tcf_proto *tp,
1594			 struct tcf_result *res, bool compat_mode)
1595{
1596#if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1597	u32 last_executed_chain = 0;
1598
1599	return __tcf_classify(skb, tp, tp, res, compat_mode,
1600			      &last_executed_chain);
1601#else
1602	u32 last_executed_chain = tp ? tp->chain->index : 0;
1603	const struct tcf_proto *orig_tp = tp;
1604	struct tc_skb_ext *ext;
1605	int ret;
1606
1607	ext = skb_ext_find(skb, TC_SKB_EXT);
1608
1609	if (ext && ext->chain) {
1610		struct tcf_chain *fchain;
1611
1612		fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain);
1613		if (!fchain)
1614			return TC_ACT_SHOT;
1615
1616		/* Consume, so cloned/redirect skbs won't inherit ext */
1617		skb_ext_del(skb, TC_SKB_EXT);
1618
1619		tp = rcu_dereference_bh(fchain->filter_chain);
1620		last_executed_chain = fchain->index;
1621	}
1622
1623	ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,
1624			     &last_executed_chain);
1625
1626	/* If we missed on some chain */
1627	if (ret == TC_ACT_UNSPEC && last_executed_chain) {
1628		ext = skb_ext_add(skb, TC_SKB_EXT);
1629		if (WARN_ON_ONCE(!ext))
1630			return TC_ACT_SHOT;
1631		ext->chain = last_executed_chain;
1632		ext->mru = qdisc_skb_cb(skb)->mru;
1633	}
1634
1635	return ret;
1636#endif
1637}
1638EXPORT_SYMBOL(tcf_classify_ingress);
1639
1640struct tcf_chain_info {
1641	struct tcf_proto __rcu **pprev;
1642	struct tcf_proto __rcu *next;
1643};
1644
1645static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1646					   struct tcf_chain_info *chain_info)
1647{
1648	return tcf_chain_dereference(*chain_info->pprev, chain);
1649}
1650
1651static int tcf_chain_tp_insert(struct tcf_chain *chain,
1652			       struct tcf_chain_info *chain_info,
1653			       struct tcf_proto *tp)
1654{
1655	if (chain->flushing)
1656		return -EAGAIN;
1657
1658	if (*chain_info->pprev == chain->filter_chain)
1659		tcf_chain0_head_change(chain, tp);
1660	tcf_proto_get(tp);
1661	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1662	rcu_assign_pointer(*chain_info->pprev, tp);
1663
1664	return 0;
1665}
1666
1667static void tcf_chain_tp_remove(struct tcf_chain *chain,
1668				struct tcf_chain_info *chain_info,
1669				struct tcf_proto *tp)
1670{
1671	struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1672
1673	tcf_proto_mark_delete(tp);
1674	if (tp == chain->filter_chain)
1675		tcf_chain0_head_change(chain, next);
1676	RCU_INIT_POINTER(*chain_info->pprev, next);
1677}
1678
1679static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1680					   struct tcf_chain_info *chain_info,
1681					   u32 protocol, u32 prio,
1682					   bool prio_allocate);
1683
1684/* Try to insert new proto.
1685 * If proto with specified priority already exists, free new proto
1686 * and return existing one.
1687 */
1688
1689static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1690						    struct tcf_proto *tp_new,
1691						    u32 protocol, u32 prio,
1692						    bool rtnl_held)
1693{
1694	struct tcf_chain_info chain_info;
1695	struct tcf_proto *tp;
1696	int err = 0;
1697
1698	mutex_lock(&chain->filter_chain_lock);
1699
1700	if (tcf_proto_exists_destroying(chain, tp_new)) {
1701		mutex_unlock(&chain->filter_chain_lock);
1702		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1703		return ERR_PTR(-EAGAIN);
1704	}
1705
1706	tp = tcf_chain_tp_find(chain, &chain_info,
1707			       protocol, prio, false);
1708	if (!tp)
1709		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1710	mutex_unlock(&chain->filter_chain_lock);
1711
1712	if (tp) {
1713		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1714		tp_new = tp;
1715	} else if (err) {
1716		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1717		tp_new = ERR_PTR(err);
1718	}
1719
1720	return tp_new;
1721}
1722
1723static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1724				      struct tcf_proto *tp, bool rtnl_held,
1725				      struct netlink_ext_ack *extack)
1726{
1727	struct tcf_chain_info chain_info;
1728	struct tcf_proto *tp_iter;
1729	struct tcf_proto **pprev;
1730	struct tcf_proto *next;
1731
1732	mutex_lock(&chain->filter_chain_lock);
1733
1734	/* Atomically find and remove tp from chain. */
1735	for (pprev = &chain->filter_chain;
1736	     (tp_iter = tcf_chain_dereference(*pprev, chain));
1737	     pprev = &tp_iter->next) {
1738		if (tp_iter == tp) {
1739			chain_info.pprev = pprev;
1740			chain_info.next = tp_iter->next;
1741			WARN_ON(tp_iter->deleting);
1742			break;
 
 
 
 
 
 
 
 
 
 
 
1743		}
1744	}
1745	/* Verify that tp still exists and no new filters were inserted
1746	 * concurrently.
1747	 * Mark tp for deletion if it is empty.
1748	 */
1749	if (!tp_iter || !tcf_proto_check_delete(tp)) {
1750		mutex_unlock(&chain->filter_chain_lock);
1751		return;
1752	}
1753
1754	tcf_proto_signal_destroying(chain, tp);
1755	next = tcf_chain_dereference(chain_info.next, chain);
1756	if (tp == chain->filter_chain)
1757		tcf_chain0_head_change(chain, next);
1758	RCU_INIT_POINTER(*chain_info.pprev, next);
1759	mutex_unlock(&chain->filter_chain_lock);
1760
1761	tcf_proto_put(tp, rtnl_held, extack);
1762}
1763
1764static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1765					   struct tcf_chain_info *chain_info,
1766					   u32 protocol, u32 prio,
1767					   bool prio_allocate)
1768{
1769	struct tcf_proto **pprev;
1770	struct tcf_proto *tp;
1771
1772	/* Check the chain for existence of proto-tcf with this priority */
1773	for (pprev = &chain->filter_chain;
1774	     (tp = tcf_chain_dereference(*pprev, chain));
1775	     pprev = &tp->next) {
1776		if (tp->prio >= prio) {
1777			if (tp->prio == prio) {
1778				if (prio_allocate ||
1779				    (tp->protocol != protocol && protocol))
1780					return ERR_PTR(-EINVAL);
1781			} else {
1782				tp = NULL;
1783			}
1784			break;
1785		}
1786	}
1787	chain_info->pprev = pprev;
1788	if (tp) {
1789		chain_info->next = tp->next;
1790		tcf_proto_get(tp);
1791	} else {
1792		chain_info->next = NULL;
 
1793	}
1794	return tp;
 
 
 
 
 
 
 
1795}
1796
1797static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1798			 struct tcf_proto *tp, struct tcf_block *block,
1799			 struct Qdisc *q, u32 parent, void *fh,
1800			 u32 portid, u32 seq, u16 flags, int event,
1801			 bool terse_dump, bool rtnl_held)
1802{
1803	struct tcmsg *tcm;
1804	struct nlmsghdr  *nlh;
1805	unsigned char *b = skb_tail_pointer(skb);
1806
1807	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1808	if (!nlh)
1809		goto out_nlmsg_trim;
1810	tcm = nlmsg_data(nlh);
1811	tcm->tcm_family = AF_UNSPEC;
1812	tcm->tcm__pad1 = 0;
1813	tcm->tcm__pad2 = 0;
1814	if (q) {
1815		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1816		tcm->tcm_parent = parent;
1817	} else {
1818		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1819		tcm->tcm_block_index = block->index;
1820	}
1821	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1822	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1823		goto nla_put_failure;
1824	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1825		goto nla_put_failure;
1826	if (!fh) {
1827		tcm->tcm_handle = 0;
1828	} else if (terse_dump) {
1829		if (tp->ops->terse_dump) {
1830			if (tp->ops->terse_dump(net, tp, fh, skb, tcm,
1831						rtnl_held) < 0)
1832				goto nla_put_failure;
1833		} else {
1834			goto cls_op_not_supp;
1835		}
1836	} else {
1837		if (tp->ops->dump &&
1838		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1839			goto nla_put_failure;
1840	}
1841	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1842	return skb->len;
1843
1844out_nlmsg_trim:
1845nla_put_failure:
1846cls_op_not_supp:
1847	nlmsg_trim(skb, b);
1848	return -1;
1849}
1850
1851static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1852			  struct nlmsghdr *n, struct tcf_proto *tp,
1853			  struct tcf_block *block, struct Qdisc *q,
1854			  u32 parent, void *fh, int event, bool unicast,
1855			  bool rtnl_held)
1856{
1857	struct sk_buff *skb;
1858	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1859	int err = 0;
1860
1861	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1862	if (!skb)
1863		return -ENOBUFS;
1864
1865	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1866			  n->nlmsg_seq, n->nlmsg_flags, event,
1867			  false, rtnl_held) <= 0) {
1868		kfree_skb(skb);
1869		return -EINVAL;
1870	}
1871
1872	if (unicast)
1873		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1874	else
1875		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1876				     n->nlmsg_flags & NLM_F_ECHO);
1877
1878	if (err > 0)
1879		err = 0;
1880	return err;
1881}
1882
1883static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1884			      struct nlmsghdr *n, struct tcf_proto *tp,
1885			      struct tcf_block *block, struct Qdisc *q,
1886			      u32 parent, void *fh, bool unicast, bool *last,
1887			      bool rtnl_held, struct netlink_ext_ack *extack)
1888{
1889	struct sk_buff *skb;
1890	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1891	int err;
1892
1893	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1894	if (!skb)
1895		return -ENOBUFS;
1896
1897	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1898			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1899			  false, rtnl_held) <= 0) {
1900		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1901		kfree_skb(skb);
1902		return -EINVAL;
1903	}
1904
1905	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1906	if (err) {
1907		kfree_skb(skb);
1908		return err;
1909	}
1910
1911	if (unicast)
1912		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1913	else
1914		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1915				     n->nlmsg_flags & NLM_F_ECHO);
1916	if (err < 0)
1917		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1918
1919	if (err > 0)
1920		err = 0;
1921	return err;
1922}
1923
1924static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1925				 struct tcf_block *block, struct Qdisc *q,
1926				 u32 parent, struct nlmsghdr *n,
1927				 struct tcf_chain *chain, int event,
1928				 bool rtnl_held)
1929{
1930	struct tcf_proto *tp;
1931
1932	for (tp = tcf_get_next_proto(chain, NULL, rtnl_held);
1933	     tp; tp = tcf_get_next_proto(chain, tp, rtnl_held))
1934		tfilter_notify(net, oskb, n, tp, block,
1935			       q, parent, NULL, event, false, rtnl_held);
1936}
1937
1938static void tfilter_put(struct tcf_proto *tp, void *fh)
1939{
1940	if (tp->ops->put && fh)
1941		tp->ops->put(tp, fh);
1942}
1943
1944static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1945			  struct netlink_ext_ack *extack)
1946{
1947	struct net *net = sock_net(skb->sk);
1948	struct nlattr *tca[TCA_MAX + 1];
1949	char name[IFNAMSIZ];
1950	struct tcmsg *t;
1951	u32 protocol;
1952	u32 prio;
1953	bool prio_allocate;
1954	u32 parent;
1955	u32 chain_index;
1956	struct Qdisc *q = NULL;
1957	struct tcf_chain_info chain_info;
1958	struct tcf_chain *chain = NULL;
1959	struct tcf_block *block;
1960	struct tcf_proto *tp;
1961	unsigned long cl;
1962	void *fh;
1963	int err;
1964	int tp_created;
1965	bool rtnl_held = false;
1966
1967	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1968		return -EPERM;
1969
1970replay:
1971	tp_created = 0;
1972
1973	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
1974				     rtm_tca_policy, extack);
1975	if (err < 0)
1976		return err;
1977
1978	t = nlmsg_data(n);
1979	protocol = TC_H_MIN(t->tcm_info);
1980	prio = TC_H_MAJ(t->tcm_info);
1981	prio_allocate = false;
1982	parent = t->tcm_parent;
1983	tp = NULL;
1984	cl = 0;
1985	block = NULL;
1986
1987	if (prio == 0) {
1988		/* If no priority is provided by the user,
1989		 * we allocate one.
1990		 */
1991		if (n->nlmsg_flags & NLM_F_CREATE) {
1992			prio = TC_H_MAKE(0x80000000U, 0U);
1993			prio_allocate = true;
1994		} else {
1995			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
1996			return -ENOENT;
1997		}
1998	}
1999
2000	/* Find head of filter chain. */
2001
2002	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2003	if (err)
2004		return err;
2005
2006	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2007		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2008		err = -EINVAL;
2009		goto errout;
2010	}
2011
2012	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
2013	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
2014	 * type is not specified, classifier is not unlocked.
2015	 */
2016	if (rtnl_held ||
2017	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2018	    !tcf_proto_is_unlocked(name)) {
2019		rtnl_held = true;
2020		rtnl_lock();
2021	}
2022
2023	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2024	if (err)
2025		goto errout;
2026
2027	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2028				 extack);
2029	if (IS_ERR(block)) {
2030		err = PTR_ERR(block);
2031		goto errout;
2032	}
2033	block->classid = parent;
2034
2035	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2036	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2037		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2038		err = -EINVAL;
2039		goto errout;
2040	}
2041	chain = tcf_chain_get(block, chain_index, true);
2042	if (!chain) {
2043		NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2044		err = -ENOMEM;
2045		goto errout;
2046	}
2047
2048	mutex_lock(&chain->filter_chain_lock);
2049	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2050			       prio, prio_allocate);
2051	if (IS_ERR(tp)) {
2052		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2053		err = PTR_ERR(tp);
2054		goto errout_locked;
2055	}
2056
2057	if (tp == NULL) {
2058		struct tcf_proto *tp_new = NULL;
2059
2060		if (chain->flushing) {
2061			err = -EAGAIN;
2062			goto errout_locked;
2063		}
2064
2065		/* Proto-tcf does not exist, create new one */
2066
2067		if (tca[TCA_KIND] == NULL || !protocol) {
2068			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2069			err = -EINVAL;
2070			goto errout_locked;
2071		}
2072
2073		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2074			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2075			err = -ENOENT;
2076			goto errout_locked;
2077		}
2078
2079		if (prio_allocate)
2080			prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2081							       &chain_info));
2082
2083		mutex_unlock(&chain->filter_chain_lock);
2084		tp_new = tcf_proto_create(name, protocol, prio, chain,
2085					  rtnl_held, extack);
2086		if (IS_ERR(tp_new)) {
2087			err = PTR_ERR(tp_new);
2088			goto errout_tp;
2089		}
2090
2091		tp_created = 1;
2092		tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2093						rtnl_held);
2094		if (IS_ERR(tp)) {
2095			err = PTR_ERR(tp);
2096			goto errout_tp;
2097		}
2098	} else {
2099		mutex_unlock(&chain->filter_chain_lock);
2100	}
2101
2102	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2103		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2104		err = -EINVAL;
2105		goto errout;
2106	}
2107
2108	fh = tp->ops->get(tp, t->tcm_handle);
2109
2110	if (!fh) {
2111		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2112			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2113			err = -ENOENT;
2114			goto errout;
2115		}
2116	} else if (n->nlmsg_flags & NLM_F_EXCL) {
2117		tfilter_put(tp, fh);
2118		NL_SET_ERR_MSG(extack, "Filter already exists");
2119		err = -EEXIST;
2120		goto errout;
2121	}
2122
2123	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2124		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2125		err = -EINVAL;
2126		goto errout;
2127	}
2128
2129	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2130			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
2131			      rtnl_held, extack);
2132	if (err == 0) {
2133		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2134			       RTM_NEWTFILTER, false, rtnl_held);
2135		tfilter_put(tp, fh);
2136		/* q pointer is NULL for shared blocks */
2137		if (q)
2138			q->flags &= ~TCQ_F_CAN_BYPASS;
2139	}
2140
2141errout:
2142	if (err && tp_created)
2143		tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2144errout_tp:
2145	if (chain) {
2146		if (tp && !IS_ERR(tp))
2147			tcf_proto_put(tp, rtnl_held, NULL);
2148		if (!tp_created)
2149			tcf_chain_put(chain);
2150	}
2151	tcf_block_release(q, block, rtnl_held);
2152
2153	if (rtnl_held)
2154		rtnl_unlock();
2155
2156	if (err == -EAGAIN) {
2157		/* Take rtnl lock in case EAGAIN is caused by concurrent flush
2158		 * of target chain.
2159		 */
2160		rtnl_held = true;
2161		/* Replay the request. */
2162		goto replay;
2163	}
2164	return err;
2165
2166errout_locked:
2167	mutex_unlock(&chain->filter_chain_lock);
2168	goto errout;
2169}
2170
2171static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2172			  struct netlink_ext_ack *extack)
2173{
2174	struct net *net = sock_net(skb->sk);
2175	struct nlattr *tca[TCA_MAX + 1];
2176	char name[IFNAMSIZ];
2177	struct tcmsg *t;
2178	u32 protocol;
2179	u32 prio;
2180	u32 parent;
2181	u32 chain_index;
2182	struct Qdisc *q = NULL;
2183	struct tcf_chain_info chain_info;
2184	struct tcf_chain *chain = NULL;
2185	struct tcf_block *block = NULL;
2186	struct tcf_proto *tp = NULL;
2187	unsigned long cl = 0;
2188	void *fh = NULL;
2189	int err;
2190	bool rtnl_held = false;
2191
2192	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2193		return -EPERM;
 
 
 
2194
2195	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2196				     rtm_tca_policy, extack);
2197	if (err < 0)
2198		return err;
2199
2200	t = nlmsg_data(n);
2201	protocol = TC_H_MIN(t->tcm_info);
2202	prio = TC_H_MAJ(t->tcm_info);
2203	parent = t->tcm_parent;
2204
2205	if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2206		NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2207		return -ENOENT;
2208	}
2209
2210	/* Find head of filter chain. */
2211
2212	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2213	if (err)
2214		return err;
2215
2216	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2217		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2218		err = -EINVAL;
2219		goto errout;
2220	}
2221	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2222	 * found), qdisc is not unlocked, classifier type is not specified,
2223	 * classifier is not unlocked.
2224	 */
2225	if (!prio ||
2226	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2227	    !tcf_proto_is_unlocked(name)) {
2228		rtnl_held = true;
2229		rtnl_lock();
2230	}
2231
2232	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2233	if (err)
2234		goto errout;
2235
2236	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2237				 extack);
2238	if (IS_ERR(block)) {
2239		err = PTR_ERR(block);
2240		goto errout;
2241	}
2242
2243	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2244	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2245		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2246		err = -EINVAL;
2247		goto errout;
2248	}
2249	chain = tcf_chain_get(block, chain_index, false);
2250	if (!chain) {
2251		/* User requested flush on non-existent chain. Nothing to do,
2252		 * so just return success.
2253		 */
2254		if (prio == 0) {
2255			err = 0;
2256			goto errout;
2257		}
2258		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2259		err = -ENOENT;
2260		goto errout;
2261	}
2262
2263	if (prio == 0) {
2264		tfilter_notify_chain(net, skb, block, q, parent, n,
2265				     chain, RTM_DELTFILTER, rtnl_held);
2266		tcf_chain_flush(chain, rtnl_held);
2267		err = 0;
2268		goto errout;
2269	}
2270
2271	mutex_lock(&chain->filter_chain_lock);
2272	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2273			       prio, false);
2274	if (!tp || IS_ERR(tp)) {
2275		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2276		err = tp ? PTR_ERR(tp) : -ENOENT;
2277		goto errout_locked;
2278	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2279		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2280		err = -EINVAL;
2281		goto errout_locked;
2282	} else if (t->tcm_handle == 0) {
2283		tcf_proto_signal_destroying(chain, tp);
2284		tcf_chain_tp_remove(chain, &chain_info, tp);
2285		mutex_unlock(&chain->filter_chain_lock);
2286
2287		tcf_proto_put(tp, rtnl_held, NULL);
2288		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2289			       RTM_DELTFILTER, false, rtnl_held);
2290		err = 0;
2291		goto errout;
2292	}
2293	mutex_unlock(&chain->filter_chain_lock);
2294
2295	fh = tp->ops->get(tp, t->tcm_handle);
2296
2297	if (!fh) {
2298		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2299		err = -ENOENT;
2300	} else {
2301		bool last;
2302
2303		err = tfilter_del_notify(net, skb, n, tp, block,
2304					 q, parent, fh, false, &last,
2305					 rtnl_held, extack);
2306
2307		if (err)
2308			goto errout;
2309		if (last)
2310			tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2311	}
2312
2313errout:
2314	if (chain) {
2315		if (tp && !IS_ERR(tp))
2316			tcf_proto_put(tp, rtnl_held, NULL);
2317		tcf_chain_put(chain);
2318	}
2319	tcf_block_release(q, block, rtnl_held);
2320
2321	if (rtnl_held)
2322		rtnl_unlock();
2323
2324	return err;
2325
2326errout_locked:
2327	mutex_unlock(&chain->filter_chain_lock);
2328	goto errout;
2329}
2330
2331static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2332			  struct netlink_ext_ack *extack)
2333{
2334	struct net *net = sock_net(skb->sk);
2335	struct nlattr *tca[TCA_MAX + 1];
2336	char name[IFNAMSIZ];
2337	struct tcmsg *t;
2338	u32 protocol;
2339	u32 prio;
2340	u32 parent;
2341	u32 chain_index;
2342	struct Qdisc *q = NULL;
2343	struct tcf_chain_info chain_info;
2344	struct tcf_chain *chain = NULL;
2345	struct tcf_block *block = NULL;
2346	struct tcf_proto *tp = NULL;
2347	unsigned long cl = 0;
2348	void *fh = NULL;
2349	int err;
2350	bool rtnl_held = false;
2351
2352	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2353				     rtm_tca_policy, extack);
2354	if (err < 0)
2355		return err;
2356
2357	t = nlmsg_data(n);
2358	protocol = TC_H_MIN(t->tcm_info);
2359	prio = TC_H_MAJ(t->tcm_info);
2360	parent = t->tcm_parent;
2361
2362	if (prio == 0) {
2363		NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2364		return -ENOENT;
2365	}
2366
2367	/* Find head of filter chain. */
2368
2369	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2370	if (err)
2371		return err;
2372
2373	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2374		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2375		err = -EINVAL;
2376		goto errout;
2377	}
2378	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2379	 * unlocked, classifier type is not specified, classifier is not
2380	 * unlocked.
2381	 */
2382	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2383	    !tcf_proto_is_unlocked(name)) {
2384		rtnl_held = true;
2385		rtnl_lock();
2386	}
2387
2388	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2389	if (err)
2390		goto errout;
2391
2392	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2393				 extack);
2394	if (IS_ERR(block)) {
2395		err = PTR_ERR(block);
2396		goto errout;
2397	}
2398
2399	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2400	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2401		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2402		err = -EINVAL;
2403		goto errout;
2404	}
2405	chain = tcf_chain_get(block, chain_index, false);
2406	if (!chain) {
2407		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2408		err = -EINVAL;
2409		goto errout;
2410	}
2411
2412	mutex_lock(&chain->filter_chain_lock);
2413	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2414			       prio, false);
2415	mutex_unlock(&chain->filter_chain_lock);
2416	if (!tp || IS_ERR(tp)) {
2417		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2418		err = tp ? PTR_ERR(tp) : -ENOENT;
2419		goto errout;
2420	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2421		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2422		err = -EINVAL;
2423		goto errout;
2424	}
2425
2426	fh = tp->ops->get(tp, t->tcm_handle);
2427
2428	if (!fh) {
2429		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2430		err = -ENOENT;
2431	} else {
2432		err = tfilter_notify(net, skb, n, tp, block, q, parent,
2433				     fh, RTM_NEWTFILTER, true, rtnl_held);
2434		if (err < 0)
2435			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2436	}
2437
2438	tfilter_put(tp, fh);
2439errout:
2440	if (chain) {
2441		if (tp && !IS_ERR(tp))
2442			tcf_proto_put(tp, rtnl_held, NULL);
2443		tcf_chain_put(chain);
2444	}
2445	tcf_block_release(q, block, rtnl_held);
2446
2447	if (rtnl_held)
2448		rtnl_unlock();
2449
2450	return err;
2451}
2452
2453struct tcf_dump_args {
2454	struct tcf_walker w;
2455	struct sk_buff *skb;
2456	struct netlink_callback *cb;
2457	struct tcf_block *block;
2458	struct Qdisc *q;
2459	u32 parent;
2460	bool terse_dump;
2461};
2462
2463static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2464{
2465	struct tcf_dump_args *a = (void *)arg;
2466	struct net *net = sock_net(a->skb->sk);
2467
2468	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2469			     n, NETLINK_CB(a->cb->skb).portid,
2470			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2471			     RTM_NEWTFILTER, a->terse_dump, true);
2472}
2473
2474static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2475			   struct sk_buff *skb, struct netlink_callback *cb,
2476			   long index_start, long *p_index, bool terse)
2477{
2478	struct net *net = sock_net(skb->sk);
2479	struct tcf_block *block = chain->block;
2480	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2481	struct tcf_proto *tp, *tp_prev;
2482	struct tcf_dump_args arg;
2483
2484	for (tp = __tcf_get_next_proto(chain, NULL);
2485	     tp;
2486	     tp_prev = tp,
2487		     tp = __tcf_get_next_proto(chain, tp),
2488		     tcf_proto_put(tp_prev, true, NULL),
2489		     (*p_index)++) {
2490		if (*p_index < index_start)
2491			continue;
2492		if (TC_H_MAJ(tcm->tcm_info) &&
2493		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
2494			continue;
2495		if (TC_H_MIN(tcm->tcm_info) &&
2496		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
2497			continue;
2498		if (*p_index > index_start)
2499			memset(&cb->args[1], 0,
2500			       sizeof(cb->args) - sizeof(cb->args[0]));
2501		if (cb->args[1] == 0) {
2502			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2503					  NETLINK_CB(cb->skb).portid,
2504					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
2505					  RTM_NEWTFILTER, false, true) <= 0)
2506				goto errout;
 
2507			cb->args[1] = 1;
2508		}
2509		if (!tp->ops->walk)
2510			continue;
2511		arg.w.fn = tcf_node_dump;
2512		arg.skb = skb;
2513		arg.cb = cb;
2514		arg.block = block;
2515		arg.q = q;
2516		arg.parent = parent;
2517		arg.w.stop = 0;
2518		arg.w.skip = cb->args[1] - 1;
2519		arg.w.count = 0;
2520		arg.w.cookie = cb->args[2];
2521		arg.terse_dump = terse;
2522		tp->ops->walk(tp, &arg.w, true);
2523		cb->args[2] = arg.w.cookie;
2524		cb->args[1] = arg.w.count + 1;
2525		if (arg.w.stop)
2526			goto errout;
2527	}
2528	return true;
2529
2530errout:
2531	tcf_proto_put(tp, true, NULL);
2532	return false;
2533}
2534
2535static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = {
2536	[TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE),
2537};
2538
2539/* called with RTNL */
2540static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2541{
2542	struct tcf_chain *chain, *chain_prev;
2543	struct net *net = sock_net(skb->sk);
2544	struct nlattr *tca[TCA_MAX + 1];
2545	struct Qdisc *q = NULL;
2546	struct tcf_block *block;
2547	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2548	bool terse_dump = false;
2549	long index_start;
2550	long index;
2551	u32 parent;
2552	int err;
2553
2554	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2555		return skb->len;
2556
2557	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2558				     tcf_tfilter_dump_policy, cb->extack);
2559	if (err)
2560		return err;
2561
2562	if (tca[TCA_DUMP_FLAGS]) {
2563		struct nla_bitfield32 flags =
2564			nla_get_bitfield32(tca[TCA_DUMP_FLAGS]);
2565
2566		terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE;
2567	}
2568
2569	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2570		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2571		if (!block)
2572			goto out;
2573		/* If we work with block index, q is NULL and parent value
2574		 * will never be used in the following code. The check
2575		 * in tcf_fill_node prevents it. However, compiler does not
2576		 * see that far, so set parent to zero to silence the warning
2577		 * about parent being uninitialized.
2578		 */
2579		parent = 0;
2580	} else {
2581		const struct Qdisc_class_ops *cops;
2582		struct net_device *dev;
2583		unsigned long cl = 0;
2584
2585		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2586		if (!dev)
2587			return skb->len;
2588
2589		parent = tcm->tcm_parent;
2590		if (!parent)
2591			q = dev->qdisc;
2592		else
2593			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2594		if (!q)
2595			goto out;
2596		cops = q->ops->cl_ops;
2597		if (!cops)
2598			goto out;
2599		if (!cops->tcf_block)
2600			goto out;
2601		if (TC_H_MIN(tcm->tcm_parent)) {
2602			cl = cops->find(q, tcm->tcm_parent);
2603			if (cl == 0)
2604				goto out;
2605		}
2606		block = cops->tcf_block(q, cl, NULL);
2607		if (!block)
2608			goto out;
2609		parent = block->classid;
2610		if (tcf_block_shared(block))
2611			q = NULL;
2612	}
2613
2614	index_start = cb->args[0];
2615	index = 0;
2616
2617	for (chain = __tcf_get_next_chain(block, NULL);
2618	     chain;
2619	     chain_prev = chain,
2620		     chain = __tcf_get_next_chain(block, chain),
2621		     tcf_chain_put(chain_prev)) {
2622		if (tca[TCA_CHAIN] &&
2623		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2624			continue;
2625		if (!tcf_chain_dump(chain, q, parent, skb, cb,
2626				    index_start, &index, terse_dump)) {
2627			tcf_chain_put(chain);
2628			err = -EMSGSIZE;
2629			break;
2630		}
2631	}
2632
2633	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2634		tcf_block_refcnt_put(block, true);
2635	cb->args[0] = index;
2636
2637out:
2638	/* If we did no progress, the error (EMSGSIZE) is real */
2639	if (skb->len == 0 && err)
2640		return err;
2641	return skb->len;
2642}
2643
2644static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2645			      void *tmplt_priv, u32 chain_index,
2646			      struct net *net, struct sk_buff *skb,
2647			      struct tcf_block *block,
2648			      u32 portid, u32 seq, u16 flags, int event)
2649{
2650	unsigned char *b = skb_tail_pointer(skb);
2651	const struct tcf_proto_ops *ops;
2652	struct nlmsghdr *nlh;
2653	struct tcmsg *tcm;
2654	void *priv;
2655
2656	ops = tmplt_ops;
2657	priv = tmplt_priv;
2658
2659	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2660	if (!nlh)
2661		goto out_nlmsg_trim;
2662	tcm = nlmsg_data(nlh);
2663	tcm->tcm_family = AF_UNSPEC;
2664	tcm->tcm__pad1 = 0;
2665	tcm->tcm__pad2 = 0;
2666	tcm->tcm_handle = 0;
2667	if (block->q) {
2668		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2669		tcm->tcm_parent = block->q->handle;
2670	} else {
2671		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2672		tcm->tcm_block_index = block->index;
2673	}
2674
2675	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2676		goto nla_put_failure;
2677
2678	if (ops) {
2679		if (nla_put_string(skb, TCA_KIND, ops->kind))
2680			goto nla_put_failure;
2681		if (ops->tmplt_dump(skb, net, priv) < 0)
2682			goto nla_put_failure;
2683	}
2684
2685	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2686	return skb->len;
2687
2688out_nlmsg_trim:
2689nla_put_failure:
2690	nlmsg_trim(skb, b);
2691	return -EMSGSIZE;
2692}
2693
2694static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2695			   u32 seq, u16 flags, int event, bool unicast)
2696{
2697	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2698	struct tcf_block *block = chain->block;
2699	struct net *net = block->net;
2700	struct sk_buff *skb;
2701	int err = 0;
2702
2703	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2704	if (!skb)
2705		return -ENOBUFS;
2706
2707	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2708			       chain->index, net, skb, block, portid,
2709			       seq, flags, event) <= 0) {
2710		kfree_skb(skb);
2711		return -EINVAL;
2712	}
2713
2714	if (unicast)
2715		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2716	else
2717		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2718				     flags & NLM_F_ECHO);
2719
2720	if (err > 0)
2721		err = 0;
2722	return err;
2723}
2724
2725static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2726				  void *tmplt_priv, u32 chain_index,
2727				  struct tcf_block *block, struct sk_buff *oskb,
2728				  u32 seq, u16 flags, bool unicast)
2729{
2730	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2731	struct net *net = block->net;
2732	struct sk_buff *skb;
2733
2734	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2735	if (!skb)
2736		return -ENOBUFS;
2737
2738	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2739			       block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2740		kfree_skb(skb);
2741		return -EINVAL;
2742	}
2743
2744	if (unicast)
2745		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2746
2747	return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2748}
2749
2750static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2751			      struct nlattr **tca,
2752			      struct netlink_ext_ack *extack)
2753{
2754	const struct tcf_proto_ops *ops;
2755	char name[IFNAMSIZ];
2756	void *tmplt_priv;
2757
2758	/* If kind is not set, user did not specify template. */
2759	if (!tca[TCA_KIND])
2760		return 0;
2761
2762	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2763		NL_SET_ERR_MSG(extack, "Specified TC chain template name too long");
2764		return -EINVAL;
2765	}
2766
2767	ops = tcf_proto_lookup_ops(name, true, extack);
2768	if (IS_ERR(ops))
2769		return PTR_ERR(ops);
2770	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
2771		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
2772		return -EOPNOTSUPP;
2773	}
2774
2775	tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2776	if (IS_ERR(tmplt_priv)) {
2777		module_put(ops->owner);
2778		return PTR_ERR(tmplt_priv);
2779	}
2780	chain->tmplt_ops = ops;
2781	chain->tmplt_priv = tmplt_priv;
2782	return 0;
2783}
2784
2785static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2786			       void *tmplt_priv)
2787{
2788	/* If template ops are set, no work to do for us. */
2789	if (!tmplt_ops)
2790		return;
2791
2792	tmplt_ops->tmplt_destroy(tmplt_priv);
2793	module_put(tmplt_ops->owner);
2794}
2795
2796/* Add/delete/get a chain */
2797
2798static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2799			struct netlink_ext_ack *extack)
2800{
2801	struct net *net = sock_net(skb->sk);
2802	struct nlattr *tca[TCA_MAX + 1];
2803	struct tcmsg *t;
2804	u32 parent;
2805	u32 chain_index;
2806	struct Qdisc *q = NULL;
2807	struct tcf_chain *chain = NULL;
2808	struct tcf_block *block;
2809	unsigned long cl;
2810	int err;
2811
2812	if (n->nlmsg_type != RTM_GETCHAIN &&
2813	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2814		return -EPERM;
2815
2816replay:
2817	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2818				     rtm_tca_policy, extack);
2819	if (err < 0)
2820		return err;
2821
2822	t = nlmsg_data(n);
2823	parent = t->tcm_parent;
2824	cl = 0;
2825
2826	block = tcf_block_find(net, &q, &parent, &cl,
2827			       t->tcm_ifindex, t->tcm_block_index, extack);
2828	if (IS_ERR(block))
2829		return PTR_ERR(block);
2830
2831	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2832	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2833		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2834		err = -EINVAL;
2835		goto errout_block;
2836	}
2837
2838	mutex_lock(&block->lock);
2839	chain = tcf_chain_lookup(block, chain_index);
2840	if (n->nlmsg_type == RTM_NEWCHAIN) {
2841		if (chain) {
2842			if (tcf_chain_held_by_acts_only(chain)) {
2843				/* The chain exists only because there is
2844				 * some action referencing it.
2845				 */
2846				tcf_chain_hold(chain);
2847			} else {
2848				NL_SET_ERR_MSG(extack, "Filter chain already exists");
2849				err = -EEXIST;
2850				goto errout_block_locked;
2851			}
2852		} else {
2853			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2854				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2855				err = -ENOENT;
2856				goto errout_block_locked;
2857			}
2858			chain = tcf_chain_create(block, chain_index);
2859			if (!chain) {
2860				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2861				err = -ENOMEM;
2862				goto errout_block_locked;
2863			}
2864		}
2865	} else {
2866		if (!chain || tcf_chain_held_by_acts_only(chain)) {
2867			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2868			err = -EINVAL;
2869			goto errout_block_locked;
2870		}
2871		tcf_chain_hold(chain);
2872	}
2873
2874	if (n->nlmsg_type == RTM_NEWCHAIN) {
2875		/* Modifying chain requires holding parent block lock. In case
2876		 * the chain was successfully added, take a reference to the
2877		 * chain. This ensures that an empty chain does not disappear at
2878		 * the end of this function.
2879		 */
2880		tcf_chain_hold(chain);
2881		chain->explicitly_created = true;
2882	}
2883	mutex_unlock(&block->lock);
2884
2885	switch (n->nlmsg_type) {
2886	case RTM_NEWCHAIN:
2887		err = tc_chain_tmplt_add(chain, net, tca, extack);
2888		if (err) {
2889			tcf_chain_put_explicitly_created(chain);
2890			goto errout;
2891		}
2892
2893		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2894				RTM_NEWCHAIN, false);
2895		break;
2896	case RTM_DELCHAIN:
2897		tfilter_notify_chain(net, skb, block, q, parent, n,
2898				     chain, RTM_DELTFILTER, true);
2899		/* Flush the chain first as the user requested chain removal. */
2900		tcf_chain_flush(chain, true);
2901		/* In case the chain was successfully deleted, put a reference
2902		 * to the chain previously taken during addition.
2903		 */
2904		tcf_chain_put_explicitly_created(chain);
2905		break;
2906	case RTM_GETCHAIN:
2907		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2908				      n->nlmsg_seq, n->nlmsg_type, true);
2909		if (err < 0)
2910			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2911		break;
2912	default:
2913		err = -EOPNOTSUPP;
2914		NL_SET_ERR_MSG(extack, "Unsupported message type");
2915		goto errout;
2916	}
2917
2918errout:
2919	tcf_chain_put(chain);
2920errout_block:
2921	tcf_block_release(q, block, true);
2922	if (err == -EAGAIN)
2923		/* Replay the request. */
2924		goto replay;
2925	return err;
2926
2927errout_block_locked:
2928	mutex_unlock(&block->lock);
2929	goto errout_block;
2930}
2931
2932/* called with RTNL */
2933static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2934{
2935	struct net *net = sock_net(skb->sk);
2936	struct nlattr *tca[TCA_MAX + 1];
2937	struct Qdisc *q = NULL;
2938	struct tcf_block *block;
2939	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2940	struct tcf_chain *chain;
2941	long index_start;
2942	long index;
2943	u32 parent;
2944	int err;
2945
2946	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2947		return skb->len;
2948
2949	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2950				     rtm_tca_policy, cb->extack);
2951	if (err)
2952		return err;
2953
2954	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2955		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2956		if (!block)
2957			goto out;
2958		/* If we work with block index, q is NULL and parent value
2959		 * will never be used in the following code. The check
2960		 * in tcf_fill_node prevents it. However, compiler does not
2961		 * see that far, so set parent to zero to silence the warning
2962		 * about parent being uninitialized.
2963		 */
2964		parent = 0;
2965	} else {
2966		const struct Qdisc_class_ops *cops;
2967		struct net_device *dev;
2968		unsigned long cl = 0;
2969
2970		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2971		if (!dev)
2972			return skb->len;
2973
2974		parent = tcm->tcm_parent;
2975		if (!parent) {
2976			q = dev->qdisc;
2977			parent = q->handle;
2978		} else {
2979			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2980		}
2981		if (!q)
2982			goto out;
2983		cops = q->ops->cl_ops;
2984		if (!cops)
2985			goto out;
2986		if (!cops->tcf_block)
2987			goto out;
2988		if (TC_H_MIN(tcm->tcm_parent)) {
2989			cl = cops->find(q, tcm->tcm_parent);
2990			if (cl == 0)
2991				goto out;
2992		}
2993		block = cops->tcf_block(q, cl, NULL);
2994		if (!block)
2995			goto out;
2996		if (tcf_block_shared(block))
2997			q = NULL;
2998	}
2999
3000	index_start = cb->args[0];
3001	index = 0;
3002
3003	mutex_lock(&block->lock);
3004	list_for_each_entry(chain, &block->chain_list, list) {
3005		if ((tca[TCA_CHAIN] &&
3006		     nla_get_u32(tca[TCA_CHAIN]) != chain->index))
3007			continue;
3008		if (index < index_start) {
3009			index++;
3010			continue;
3011		}
3012		if (tcf_chain_held_by_acts_only(chain))
3013			continue;
3014		err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
3015					 chain->index, net, skb, block,
3016					 NETLINK_CB(cb->skb).portid,
3017					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
3018					 RTM_NEWCHAIN);
3019		if (err <= 0)
3020			break;
3021		index++;
3022	}
3023	mutex_unlock(&block->lock);
3024
3025	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
3026		tcf_block_refcnt_put(block, true);
3027	cb->args[0] = index;
3028
3029out:
3030	/* If we did no progress, the error (EMSGSIZE) is real */
3031	if (skb->len == 0 && err)
3032		return err;
3033	return skb->len;
3034}
3035
3036void tcf_exts_destroy(struct tcf_exts *exts)
3037{
3038#ifdef CONFIG_NET_CLS_ACT
3039	if (exts->actions) {
3040		tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3041		kfree(exts->actions);
3042	}
3043	exts->nr_actions = 0;
3044#endif
3045}
3046EXPORT_SYMBOL(tcf_exts_destroy);
3047
3048int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3049		      struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
3050		      bool rtnl_held, struct netlink_ext_ack *extack)
3051{
 
 
3052#ifdef CONFIG_NET_CLS_ACT
3053	{
3054		struct tc_action *act;
3055		size_t attr_size = 0;
3056
3057		if (exts->police && tb[exts->police]) {
3058			act = tcf_action_init_1(net, tp, tb[exts->police],
3059						rate_tlv, "police", ovr,
3060						TCA_ACT_BIND, rtnl_held,
3061						extack);
 
 
 
 
 
 
 
3062			if (IS_ERR(act))
3063				return PTR_ERR(act);
3064
3065			act->type = exts->type = TCA_OLD_COMPAT;
3066			exts->actions[0] = act;
3067			exts->nr_actions = 1;
3068		} else if (exts->action && tb[exts->action]) {
3069			int err;
3070
3071			err = tcf_action_init(net, tp, tb[exts->action],
3072					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
3073					      exts->actions, &attr_size,
3074					      rtnl_held, extack);
3075			if (err < 0)
3076				return err;
3077			exts->nr_actions = err;
3078		}
3079	}
3080#else
3081	if ((exts->action && tb[exts->action]) ||
3082	    (exts->police && tb[exts->police])) {
3083		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3084		return -EOPNOTSUPP;
3085	}
3086#endif
3087
3088	return 0;
3089}
3090EXPORT_SYMBOL(tcf_exts_validate);
3091
3092void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
 
3093{
3094#ifdef CONFIG_NET_CLS_ACT
3095	struct tcf_exts old = *dst;
3096
3097	*dst = *src;
3098	tcf_exts_destroy(&old);
 
 
 
 
 
3099#endif
3100}
3101EXPORT_SYMBOL(tcf_exts_change);
3102
3103#ifdef CONFIG_NET_CLS_ACT
3104static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3105{
3106	if (exts->nr_actions == 0)
3107		return NULL;
3108	else
3109		return exts->actions[0];
3110}
3111#endif
3112
3113int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3114{
3115#ifdef CONFIG_NET_CLS_ACT
3116	struct nlattr *nest;
3117
3118	if (exts->action && tcf_exts_has_actions(exts)) {
3119		/*
3120		 * again for backward compatible mode - we want
3121		 * to work with both old and new modes of entering
3122		 * tc data even if iproute2  was newer - jhs
3123		 */
3124		if (exts->type != TCA_OLD_COMPAT) {
3125			nest = nla_nest_start_noflag(skb, exts->action);
 
 
3126			if (nest == NULL)
3127				goto nla_put_failure;
3128
3129			if (tcf_action_dump(skb, exts->actions, 0, 0, false)
3130			    < 0)
3131				goto nla_put_failure;
3132			nla_nest_end(skb, nest);
3133		} else if (exts->police) {
3134			struct tc_action *act = tcf_exts_first_act(exts);
3135			nest = nla_nest_start_noflag(skb, exts->police);
3136			if (nest == NULL || !act)
3137				goto nla_put_failure;
3138			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3139				goto nla_put_failure;
3140			nla_nest_end(skb, nest);
3141		}
3142	}
 
3143	return 0;
3144
3145nla_put_failure:
3146	nla_nest_cancel(skb, nest);
3147	return -1;
3148#else
3149	return 0;
3150#endif
3151}
3152EXPORT_SYMBOL(tcf_exts_dump);
3153
3154int tcf_exts_terse_dump(struct sk_buff *skb, struct tcf_exts *exts)
3155{
3156#ifdef CONFIG_NET_CLS_ACT
3157	struct nlattr *nest;
3158
3159	if (!exts->action || !tcf_exts_has_actions(exts))
3160		return 0;
3161
3162	nest = nla_nest_start_noflag(skb, exts->action);
3163	if (!nest)
3164		goto nla_put_failure;
3165
3166	if (tcf_action_dump(skb, exts->actions, 0, 0, true) < 0)
3167		goto nla_put_failure;
3168	nla_nest_end(skb, nest);
3169	return 0;
3170
3171nla_put_failure:
3172	nla_nest_cancel(skb, nest);
3173	return -1;
3174#else
3175	return 0;
3176#endif
3177}
3178EXPORT_SYMBOL(tcf_exts_terse_dump);
3179
3180int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3181{
3182#ifdef CONFIG_NET_CLS_ACT
3183	struct tc_action *a = tcf_exts_first_act(exts);
3184	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3185		return -1;
3186#endif
3187	return 0;
 
 
3188}
3189EXPORT_SYMBOL(tcf_exts_dump_stats);
3190
3191static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3192{
3193	if (*flags & TCA_CLS_FLAGS_IN_HW)
3194		return;
3195	*flags |= TCA_CLS_FLAGS_IN_HW;
3196	atomic_inc(&block->offloadcnt);
3197}
3198
3199static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3200{
3201	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3202		return;
3203	*flags &= ~TCA_CLS_FLAGS_IN_HW;
3204	atomic_dec(&block->offloadcnt);
3205}
3206
3207static void tc_cls_offload_cnt_update(struct tcf_block *block,
3208				      struct tcf_proto *tp, u32 *cnt,
3209				      u32 *flags, u32 diff, bool add)
3210{
3211	lockdep_assert_held(&block->cb_lock);
3212
3213	spin_lock(&tp->lock);
3214	if (add) {
3215		if (!*cnt)
3216			tcf_block_offload_inc(block, flags);
3217		*cnt += diff;
3218	} else {
3219		*cnt -= diff;
3220		if (!*cnt)
3221			tcf_block_offload_dec(block, flags);
3222	}
3223	spin_unlock(&tp->lock);
3224}
3225
3226static void
3227tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3228			 u32 *cnt, u32 *flags)
3229{
3230	lockdep_assert_held(&block->cb_lock);
3231
3232	spin_lock(&tp->lock);
3233	tcf_block_offload_dec(block, flags);
3234	*cnt = 0;
3235	spin_unlock(&tp->lock);
3236}
3237
3238static int
3239__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3240		   void *type_data, bool err_stop)
3241{
3242	struct flow_block_cb *block_cb;
3243	int ok_count = 0;
3244	int err;
3245
3246	list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3247		err = block_cb->cb(type, type_data, block_cb->cb_priv);
3248		if (err) {
3249			if (err_stop)
3250				return err;
3251		} else {
3252			ok_count++;
3253		}
3254	}
3255	return ok_count;
3256}
3257
3258int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3259		     void *type_data, bool err_stop, bool rtnl_held)
3260{
3261	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3262	int ok_count;
3263
3264retry:
3265	if (take_rtnl)
3266		rtnl_lock();
3267	down_read(&block->cb_lock);
3268	/* Need to obtain rtnl lock if block is bound to devs that require it.
3269	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3270	 * obtain the locks in same order here.
3271	 */
3272	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3273		up_read(&block->cb_lock);
3274		take_rtnl = true;
3275		goto retry;
3276	}
3277
3278	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3279
3280	up_read(&block->cb_lock);
3281	if (take_rtnl)
3282		rtnl_unlock();
3283	return ok_count;
3284}
3285EXPORT_SYMBOL(tc_setup_cb_call);
3286
3287/* Non-destructive filter add. If filter that wasn't already in hardware is
3288 * successfully offloaded, increment block offloads counter. On failure,
3289 * previously offloaded filter is considered to be intact and offloads counter
3290 * is not decremented.
3291 */
3292
3293int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3294		    enum tc_setup_type type, void *type_data, bool err_stop,
3295		    u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3296{
3297	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3298	int ok_count;
3299
3300retry:
3301	if (take_rtnl)
3302		rtnl_lock();
3303	down_read(&block->cb_lock);
3304	/* Need to obtain rtnl lock if block is bound to devs that require it.
3305	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3306	 * obtain the locks in same order here.
3307	 */
3308	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3309		up_read(&block->cb_lock);
3310		take_rtnl = true;
3311		goto retry;
3312	}
3313
3314	/* Make sure all netdevs sharing this block are offload-capable. */
3315	if (block->nooffloaddevcnt && err_stop) {
3316		ok_count = -EOPNOTSUPP;
3317		goto err_unlock;
3318	}
3319
3320	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3321	if (ok_count < 0)
3322		goto err_unlock;
3323
3324	if (tp->ops->hw_add)
3325		tp->ops->hw_add(tp, type_data);
3326	if (ok_count > 0)
3327		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3328					  ok_count, true);
3329err_unlock:
3330	up_read(&block->cb_lock);
3331	if (take_rtnl)
3332		rtnl_unlock();
3333	return ok_count < 0 ? ok_count : 0;
3334}
3335EXPORT_SYMBOL(tc_setup_cb_add);
3336
3337/* Destructive filter replace. If filter that wasn't already in hardware is
3338 * successfully offloaded, increment block offload counter. On failure,
3339 * previously offloaded filter is considered to be destroyed and offload counter
3340 * is decremented.
3341 */
3342
3343int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3344			enum tc_setup_type type, void *type_data, bool err_stop,
3345			u32 *old_flags, unsigned int *old_in_hw_count,
3346			u32 *new_flags, unsigned int *new_in_hw_count,
3347			bool rtnl_held)
3348{
3349	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3350	int ok_count;
3351
3352retry:
3353	if (take_rtnl)
3354		rtnl_lock();
3355	down_read(&block->cb_lock);
3356	/* Need to obtain rtnl lock if block is bound to devs that require it.
3357	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3358	 * obtain the locks in same order here.
3359	 */
3360	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3361		up_read(&block->cb_lock);
3362		take_rtnl = true;
3363		goto retry;
3364	}
3365
3366	/* Make sure all netdevs sharing this block are offload-capable. */
3367	if (block->nooffloaddevcnt && err_stop) {
3368		ok_count = -EOPNOTSUPP;
3369		goto err_unlock;
3370	}
3371
3372	tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3373	if (tp->ops->hw_del)
3374		tp->ops->hw_del(tp, type_data);
3375
3376	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3377	if (ok_count < 0)
3378		goto err_unlock;
3379
3380	if (tp->ops->hw_add)
3381		tp->ops->hw_add(tp, type_data);
3382	if (ok_count > 0)
3383		tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3384					  new_flags, ok_count, true);
3385err_unlock:
3386	up_read(&block->cb_lock);
3387	if (take_rtnl)
3388		rtnl_unlock();
3389	return ok_count < 0 ? ok_count : 0;
3390}
3391EXPORT_SYMBOL(tc_setup_cb_replace);
3392
3393/* Destroy filter and decrement block offload counter, if filter was previously
3394 * offloaded.
3395 */
3396
3397int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3398			enum tc_setup_type type, void *type_data, bool err_stop,
3399			u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3400{
3401	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3402	int ok_count;
3403
3404retry:
3405	if (take_rtnl)
3406		rtnl_lock();
3407	down_read(&block->cb_lock);
3408	/* Need to obtain rtnl lock if block is bound to devs that require it.
3409	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3410	 * obtain the locks in same order here.
3411	 */
3412	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3413		up_read(&block->cb_lock);
3414		take_rtnl = true;
3415		goto retry;
3416	}
3417
3418	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3419
3420	tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3421	if (tp->ops->hw_del)
3422		tp->ops->hw_del(tp, type_data);
3423
3424	up_read(&block->cb_lock);
3425	if (take_rtnl)
3426		rtnl_unlock();
3427	return ok_count < 0 ? ok_count : 0;
3428}
3429EXPORT_SYMBOL(tc_setup_cb_destroy);
3430
3431int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3432			  bool add, flow_setup_cb_t *cb,
3433			  enum tc_setup_type type, void *type_data,
3434			  void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3435{
3436	int err = cb(type, type_data, cb_priv);
3437
3438	if (err) {
3439		if (add && tc_skip_sw(*flags))
3440			return err;
3441	} else {
3442		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3443					  add);
3444	}
3445
3446	return 0;
3447}
3448EXPORT_SYMBOL(tc_setup_cb_reoffload);
3449
3450static int tcf_act_get_cookie(struct flow_action_entry *entry,
3451			      const struct tc_action *act)
3452{
3453	struct tc_cookie *cookie;
3454	int err = 0;
3455
3456	rcu_read_lock();
3457	cookie = rcu_dereference(act->act_cookie);
3458	if (cookie) {
3459		entry->cookie = flow_action_cookie_create(cookie->data,
3460							  cookie->len,
3461							  GFP_ATOMIC);
3462		if (!entry->cookie)
3463			err = -ENOMEM;
3464	}
3465	rcu_read_unlock();
3466	return err;
3467}
3468
3469static void tcf_act_put_cookie(struct flow_action_entry *entry)
3470{
3471	flow_action_cookie_destroy(entry->cookie);
3472}
3473
3474void tc_cleanup_flow_action(struct flow_action *flow_action)
3475{
3476	struct flow_action_entry *entry;
3477	int i;
3478
3479	flow_action_for_each(i, entry, flow_action) {
3480		tcf_act_put_cookie(entry);
3481		if (entry->destructor)
3482			entry->destructor(entry->destructor_priv);
3483	}
3484}
3485EXPORT_SYMBOL(tc_cleanup_flow_action);
3486
3487static void tcf_mirred_get_dev(struct flow_action_entry *entry,
3488			       const struct tc_action *act)
3489{
3490#ifdef CONFIG_NET_CLS_ACT
3491	entry->dev = act->ops->get_dev(act, &entry->destructor);
3492	if (!entry->dev)
3493		return;
3494	entry->destructor_priv = entry->dev;
3495#endif
3496}
3497
3498static void tcf_tunnel_encap_put_tunnel(void *priv)
3499{
3500	struct ip_tunnel_info *tunnel = priv;
3501
3502	kfree(tunnel);
3503}
3504
3505static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
3506				       const struct tc_action *act)
3507{
3508	entry->tunnel = tcf_tunnel_info_copy(act);
3509	if (!entry->tunnel)
3510		return -ENOMEM;
3511	entry->destructor = tcf_tunnel_encap_put_tunnel;
3512	entry->destructor_priv = entry->tunnel;
3513	return 0;
3514}
3515
3516static void tcf_sample_get_group(struct flow_action_entry *entry,
3517				 const struct tc_action *act)
3518{
3519#ifdef CONFIG_NET_CLS_ACT
3520	entry->sample.psample_group =
3521		act->ops->get_psample_group(act, &entry->destructor);
3522	entry->destructor_priv = entry->sample.psample_group;
3523#endif
3524}
3525
3526static void tcf_gate_entry_destructor(void *priv)
3527{
3528	struct action_gate_entry *oe = priv;
3529
3530	kfree(oe);
3531}
3532
3533static int tcf_gate_get_entries(struct flow_action_entry *entry,
3534				const struct tc_action *act)
3535{
3536	entry->gate.entries = tcf_gate_get_list(act);
3537
3538	if (!entry->gate.entries)
3539		return -EINVAL;
3540
3541	entry->destructor = tcf_gate_entry_destructor;
3542	entry->destructor_priv = entry->gate.entries;
3543
3544	return 0;
3545}
3546
3547static enum flow_action_hw_stats tc_act_hw_stats(u8 hw_stats)
3548{
3549	if (WARN_ON_ONCE(hw_stats > TCA_ACT_HW_STATS_ANY))
3550		return FLOW_ACTION_HW_STATS_DONT_CARE;
3551	else if (!hw_stats)
3552		return FLOW_ACTION_HW_STATS_DISABLED;
3553
3554	return hw_stats;
3555}
3556
3557int tc_setup_flow_action(struct flow_action *flow_action,
3558			 const struct tcf_exts *exts)
3559{
3560	struct tc_action *act;
3561	int i, j, k, err = 0;
3562
3563	BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY);
3564	BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE);
3565	BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED);
3566
3567	if (!exts)
3568		return 0;
3569
3570	j = 0;
3571	tcf_exts_for_each_action(i, act, exts) {
3572		struct flow_action_entry *entry;
3573
3574		entry = &flow_action->entries[j];
3575		spin_lock_bh(&act->tcfa_lock);
3576		err = tcf_act_get_cookie(entry, act);
3577		if (err)
3578			goto err_out_locked;
3579
3580		entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3581
3582		if (is_tcf_gact_ok(act)) {
3583			entry->id = FLOW_ACTION_ACCEPT;
3584		} else if (is_tcf_gact_shot(act)) {
3585			entry->id = FLOW_ACTION_DROP;
3586		} else if (is_tcf_gact_trap(act)) {
3587			entry->id = FLOW_ACTION_TRAP;
3588		} else if (is_tcf_gact_goto_chain(act)) {
3589			entry->id = FLOW_ACTION_GOTO;
3590			entry->chain_index = tcf_gact_goto_chain_index(act);
3591		} else if (is_tcf_mirred_egress_redirect(act)) {
3592			entry->id = FLOW_ACTION_REDIRECT;
3593			tcf_mirred_get_dev(entry, act);
3594		} else if (is_tcf_mirred_egress_mirror(act)) {
3595			entry->id = FLOW_ACTION_MIRRED;
3596			tcf_mirred_get_dev(entry, act);
3597		} else if (is_tcf_mirred_ingress_redirect(act)) {
3598			entry->id = FLOW_ACTION_REDIRECT_INGRESS;
3599			tcf_mirred_get_dev(entry, act);
3600		} else if (is_tcf_mirred_ingress_mirror(act)) {
3601			entry->id = FLOW_ACTION_MIRRED_INGRESS;
3602			tcf_mirred_get_dev(entry, act);
3603		} else if (is_tcf_vlan(act)) {
3604			switch (tcf_vlan_action(act)) {
3605			case TCA_VLAN_ACT_PUSH:
3606				entry->id = FLOW_ACTION_VLAN_PUSH;
3607				entry->vlan.vid = tcf_vlan_push_vid(act);
3608				entry->vlan.proto = tcf_vlan_push_proto(act);
3609				entry->vlan.prio = tcf_vlan_push_prio(act);
3610				break;
3611			case TCA_VLAN_ACT_POP:
3612				entry->id = FLOW_ACTION_VLAN_POP;
3613				break;
3614			case TCA_VLAN_ACT_MODIFY:
3615				entry->id = FLOW_ACTION_VLAN_MANGLE;
3616				entry->vlan.vid = tcf_vlan_push_vid(act);
3617				entry->vlan.proto = tcf_vlan_push_proto(act);
3618				entry->vlan.prio = tcf_vlan_push_prio(act);
3619				break;
3620			default:
3621				err = -EOPNOTSUPP;
3622				goto err_out_locked;
3623			}
3624		} else if (is_tcf_tunnel_set(act)) {
3625			entry->id = FLOW_ACTION_TUNNEL_ENCAP;
3626			err = tcf_tunnel_encap_get_tunnel(entry, act);
3627			if (err)
3628				goto err_out_locked;
3629		} else if (is_tcf_tunnel_release(act)) {
3630			entry->id = FLOW_ACTION_TUNNEL_DECAP;
3631		} else if (is_tcf_pedit(act)) {
3632			for (k = 0; k < tcf_pedit_nkeys(act); k++) {
3633				switch (tcf_pedit_cmd(act, k)) {
3634				case TCA_PEDIT_KEY_EX_CMD_SET:
3635					entry->id = FLOW_ACTION_MANGLE;
3636					break;
3637				case TCA_PEDIT_KEY_EX_CMD_ADD:
3638					entry->id = FLOW_ACTION_ADD;
3639					break;
3640				default:
3641					err = -EOPNOTSUPP;
3642					goto err_out_locked;
3643				}
3644				entry->mangle.htype = tcf_pedit_htype(act, k);
3645				entry->mangle.mask = tcf_pedit_mask(act, k);
3646				entry->mangle.val = tcf_pedit_val(act, k);
3647				entry->mangle.offset = tcf_pedit_offset(act, k);
3648				entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3649				entry = &flow_action->entries[++j];
3650			}
3651		} else if (is_tcf_csum(act)) {
3652			entry->id = FLOW_ACTION_CSUM;
3653			entry->csum_flags = tcf_csum_update_flags(act);
3654		} else if (is_tcf_skbedit_mark(act)) {
3655			entry->id = FLOW_ACTION_MARK;
3656			entry->mark = tcf_skbedit_mark(act);
3657		} else if (is_tcf_sample(act)) {
3658			entry->id = FLOW_ACTION_SAMPLE;
3659			entry->sample.trunc_size = tcf_sample_trunc_size(act);
3660			entry->sample.truncate = tcf_sample_truncate(act);
3661			entry->sample.rate = tcf_sample_rate(act);
3662			tcf_sample_get_group(entry, act);
3663		} else if (is_tcf_police(act)) {
3664			entry->id = FLOW_ACTION_POLICE;
3665			entry->police.burst = tcf_police_burst(act);
3666			entry->police.rate_bytes_ps =
3667				tcf_police_rate_bytes_ps(act);
3668			entry->police.mtu = tcf_police_tcfp_mtu(act);
3669			entry->police.index = act->tcfa_index;
3670		} else if (is_tcf_ct(act)) {
3671			entry->id = FLOW_ACTION_CT;
3672			entry->ct.action = tcf_ct_action(act);
3673			entry->ct.zone = tcf_ct_zone(act);
3674			entry->ct.flow_table = tcf_ct_ft(act);
3675		} else if (is_tcf_mpls(act)) {
3676			switch (tcf_mpls_action(act)) {
3677			case TCA_MPLS_ACT_PUSH:
3678				entry->id = FLOW_ACTION_MPLS_PUSH;
3679				entry->mpls_push.proto = tcf_mpls_proto(act);
3680				entry->mpls_push.label = tcf_mpls_label(act);
3681				entry->mpls_push.tc = tcf_mpls_tc(act);
3682				entry->mpls_push.bos = tcf_mpls_bos(act);
3683				entry->mpls_push.ttl = tcf_mpls_ttl(act);
3684				break;
3685			case TCA_MPLS_ACT_POP:
3686				entry->id = FLOW_ACTION_MPLS_POP;
3687				entry->mpls_pop.proto = tcf_mpls_proto(act);
3688				break;
3689			case TCA_MPLS_ACT_MODIFY:
3690				entry->id = FLOW_ACTION_MPLS_MANGLE;
3691				entry->mpls_mangle.label = tcf_mpls_label(act);
3692				entry->mpls_mangle.tc = tcf_mpls_tc(act);
3693				entry->mpls_mangle.bos = tcf_mpls_bos(act);
3694				entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
3695				break;
3696			default:
3697				goto err_out_locked;
3698			}
3699		} else if (is_tcf_skbedit_ptype(act)) {
3700			entry->id = FLOW_ACTION_PTYPE;
3701			entry->ptype = tcf_skbedit_ptype(act);
3702		} else if (is_tcf_skbedit_priority(act)) {
3703			entry->id = FLOW_ACTION_PRIORITY;
3704			entry->priority = tcf_skbedit_priority(act);
3705		} else if (is_tcf_gate(act)) {
3706			entry->id = FLOW_ACTION_GATE;
3707			entry->gate.index = tcf_gate_index(act);
3708			entry->gate.prio = tcf_gate_prio(act);
3709			entry->gate.basetime = tcf_gate_basetime(act);
3710			entry->gate.cycletime = tcf_gate_cycletime(act);
3711			entry->gate.cycletimeext = tcf_gate_cycletimeext(act);
3712			entry->gate.num_entries = tcf_gate_num_entries(act);
3713			err = tcf_gate_get_entries(entry, act);
3714			if (err)
3715				goto err_out;
3716		} else {
3717			err = -EOPNOTSUPP;
3718			goto err_out_locked;
3719		}
3720		spin_unlock_bh(&act->tcfa_lock);
3721
3722		if (!is_tcf_pedit(act))
3723			j++;
3724	}
3725
3726err_out:
3727	if (err)
3728		tc_cleanup_flow_action(flow_action);
3729
3730	return err;
3731err_out_locked:
3732	spin_unlock_bh(&act->tcfa_lock);
3733	goto err_out;
3734}
3735EXPORT_SYMBOL(tc_setup_flow_action);
3736
3737unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3738{
3739	unsigned int num_acts = 0;
3740	struct tc_action *act;
3741	int i;
3742
3743	tcf_exts_for_each_action(i, act, exts) {
3744		if (is_tcf_pedit(act))
3745			num_acts += tcf_pedit_nkeys(act);
3746		else
3747			num_acts++;
3748	}
3749	return num_acts;
3750}
3751EXPORT_SYMBOL(tcf_exts_num_actions);
3752
3753#ifdef CONFIG_NET_CLS_ACT
3754static int tcf_qevent_parse_block_index(struct nlattr *block_index_attr,
3755					u32 *p_block_index,
3756					struct netlink_ext_ack *extack)
3757{
3758	*p_block_index = nla_get_u32(block_index_attr);
3759	if (!*p_block_index) {
3760		NL_SET_ERR_MSG(extack, "Block number may not be zero");
3761		return -EINVAL;
3762	}
3763
3764	return 0;
3765}
3766
3767int tcf_qevent_init(struct tcf_qevent *qe, struct Qdisc *sch,
3768		    enum flow_block_binder_type binder_type,
3769		    struct nlattr *block_index_attr,
3770		    struct netlink_ext_ack *extack)
3771{
3772	u32 block_index;
3773	int err;
3774
3775	if (!block_index_attr)
3776		return 0;
3777
3778	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3779	if (err)
3780		return err;
3781
3782	if (!block_index)
3783		return 0;
3784
3785	qe->info.binder_type = binder_type;
3786	qe->info.chain_head_change = tcf_chain_head_change_dflt;
3787	qe->info.chain_head_change_priv = &qe->filter_chain;
3788	qe->info.block_index = block_index;
3789
3790	return tcf_block_get_ext(&qe->block, sch, &qe->info, extack);
3791}
3792EXPORT_SYMBOL(tcf_qevent_init);
3793
3794void tcf_qevent_destroy(struct tcf_qevent *qe, struct Qdisc *sch)
3795{
3796	if (qe->info.block_index)
3797		tcf_block_put_ext(qe->block, sch, &qe->info);
3798}
3799EXPORT_SYMBOL(tcf_qevent_destroy);
3800
3801int tcf_qevent_validate_change(struct tcf_qevent *qe, struct nlattr *block_index_attr,
3802			       struct netlink_ext_ack *extack)
3803{
3804	u32 block_index;
3805	int err;
3806
3807	if (!block_index_attr)
3808		return 0;
3809
3810	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3811	if (err)
3812		return err;
3813
3814	/* Bounce newly-configured block or change in block. */
3815	if (block_index != qe->info.block_index) {
3816		NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
3817		return -EINVAL;
3818	}
3819
3820	return 0;
3821}
3822EXPORT_SYMBOL(tcf_qevent_validate_change);
3823
3824struct sk_buff *tcf_qevent_handle(struct tcf_qevent *qe, struct Qdisc *sch, struct sk_buff *skb,
3825				  struct sk_buff **to_free, int *ret)
3826{
3827	struct tcf_result cl_res;
3828	struct tcf_proto *fl;
3829
3830	if (!qe->info.block_index)
3831		return skb;
3832
3833	fl = rcu_dereference_bh(qe->filter_chain);
3834
3835	switch (tcf_classify(skb, fl, &cl_res, false)) {
3836	case TC_ACT_SHOT:
3837		qdisc_qstats_drop(sch);
3838		__qdisc_drop(skb, to_free);
3839		*ret = __NET_XMIT_BYPASS;
3840		return NULL;
3841	case TC_ACT_STOLEN:
3842	case TC_ACT_QUEUED:
3843	case TC_ACT_TRAP:
3844		__qdisc_drop(skb, to_free);
3845		*ret = __NET_XMIT_STOLEN;
3846		return NULL;
3847	case TC_ACT_REDIRECT:
3848		skb_do_redirect(skb);
3849		*ret = __NET_XMIT_STOLEN;
3850		return NULL;
3851	}
3852
3853	return skb;
3854}
3855EXPORT_SYMBOL(tcf_qevent_handle);
3856
3857int tcf_qevent_dump(struct sk_buff *skb, int attr_name, struct tcf_qevent *qe)
3858{
3859	if (!qe->info.block_index)
3860		return 0;
3861	return nla_put_u32(skb, attr_name, qe->info.block_index);
3862}
3863EXPORT_SYMBOL(tcf_qevent_dump);
3864#endif
3865
3866static __net_init int tcf_net_init(struct net *net)
3867{
3868	struct tcf_net *tn = net_generic(net, tcf_net_id);
3869
3870	spin_lock_init(&tn->idr_lock);
3871	idr_init(&tn->idr);
3872	return 0;
3873}
3874
3875static void __net_exit tcf_net_exit(struct net *net)
3876{
3877	struct tcf_net *tn = net_generic(net, tcf_net_id);
3878
3879	idr_destroy(&tn->idr);
3880}
3881
3882static struct pernet_operations tcf_net_ops = {
3883	.init = tcf_net_init,
3884	.exit = tcf_net_exit,
3885	.id   = &tcf_net_id,
3886	.size = sizeof(struct tcf_net),
3887};
3888
3889static int __init tc_filter_init(void)
3890{
3891	int err;
3892
3893	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3894	if (!tc_filter_wq)
3895		return -ENOMEM;
3896
3897	err = register_pernet_subsys(&tcf_net_ops);
3898	if (err)
3899		goto err_register_pernet_subsys;
3900
3901	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3902		      RTNL_FLAG_DOIT_UNLOCKED);
3903	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3904		      RTNL_FLAG_DOIT_UNLOCKED);
3905	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3906		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3907	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3908	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3909	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3910		      tc_dump_chain, 0);
3911
3912	return 0;
3913
3914err_register_pernet_subsys:
3915	destroy_workqueue(tc_filter_wq);
3916	return err;
3917}
3918
3919subsys_initcall(tc_filter_init);