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12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/string.h>
17#include <linux/errno.h>
18#include <linux/rtnetlink.h>
19#include <linux/skbuff.h>
20#include <net/netlink.h>
21#include <net/act_api.h>
22#include <net/pkt_cls.h>
23
24struct basic_head {
25 u32 hgenerator;
26 struct list_head flist;
27 struct rcu_head rcu;
28};
29
30struct basic_filter {
31 u32 handle;
32 struct tcf_exts exts;
33 struct tcf_ematch_tree ematches;
34 struct tcf_result res;
35 struct tcf_proto *tp;
36 struct list_head link;
37 struct rcu_head rcu;
38};
39
40static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
41 struct tcf_result *res)
42{
43 int r;
44 struct basic_head *head = rcu_dereference_bh(tp->root);
45 struct basic_filter *f;
46
47 list_for_each_entry_rcu(f, &head->flist, link) {
48 if (!tcf_em_tree_match(skb, &f->ematches, NULL))
49 continue;
50 *res = f->res;
51 r = tcf_exts_exec(skb, &f->exts, res);
52 if (r < 0)
53 continue;
54 return r;
55 }
56 return -1;
57}
58
59static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
60{
61 unsigned long l = 0UL;
62 struct basic_head *head = rtnl_dereference(tp->root);
63 struct basic_filter *f;
64
65 if (head == NULL)
66 return 0UL;
67
68 list_for_each_entry(f, &head->flist, link) {
69 if (f->handle == handle) {
70 l = (unsigned long) f;
71 break;
72 }
73 }
74
75 return l;
76}
77
78static int basic_init(struct tcf_proto *tp)
79{
80 struct basic_head *head;
81
82 head = kzalloc(sizeof(*head), GFP_KERNEL);
83 if (head == NULL)
84 return -ENOBUFS;
85 INIT_LIST_HEAD(&head->flist);
86 rcu_assign_pointer(tp->root, head);
87 return 0;
88}
89
90static void basic_delete_filter(struct rcu_head *head)
91{
92 struct basic_filter *f = container_of(head, struct basic_filter, rcu);
93
94 tcf_exts_destroy(&f->exts);
95 tcf_em_tree_destroy(&f->ematches);
96 kfree(f);
97}
98
99static bool basic_destroy(struct tcf_proto *tp, bool force)
100{
101 struct basic_head *head = rtnl_dereference(tp->root);
102 struct basic_filter *f, *n;
103
104 if (!force && !list_empty(&head->flist))
105 return false;
106
107 list_for_each_entry_safe(f, n, &head->flist, link) {
108 list_del_rcu(&f->link);
109 tcf_unbind_filter(tp, &f->res);
110 call_rcu(&f->rcu, basic_delete_filter);
111 }
112 RCU_INIT_POINTER(tp->root, NULL);
113 kfree_rcu(head, rcu);
114 return true;
115}
116
117static int basic_delete(struct tcf_proto *tp, unsigned long arg)
118{
119 struct basic_filter *f = (struct basic_filter *) arg;
120
121 list_del_rcu(&f->link);
122 tcf_unbind_filter(tp, &f->res);
123 call_rcu(&f->rcu, basic_delete_filter);
124 return 0;
125}
126
127static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
128 [TCA_BASIC_CLASSID] = { .type = NLA_U32 },
129 [TCA_BASIC_EMATCHES] = { .type = NLA_NESTED },
130};
131
132static int basic_set_parms(struct net *net, struct tcf_proto *tp,
133 struct basic_filter *f, unsigned long base,
134 struct nlattr **tb,
135 struct nlattr *est, bool ovr)
136{
137 int err;
138 struct tcf_exts e;
139 struct tcf_ematch_tree t;
140
141 tcf_exts_init(&e, TCA_BASIC_ACT, TCA_BASIC_POLICE);
142 err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
143 if (err < 0)
144 return err;
145
146 err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
147 if (err < 0)
148 goto errout;
149
150 if (tb[TCA_BASIC_CLASSID]) {
151 f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
152 tcf_bind_filter(tp, &f->res, base);
153 }
154
155 tcf_exts_change(tp, &f->exts, &e);
156 tcf_em_tree_change(tp, &f->ematches, &t);
157 f->tp = tp;
158
159 return 0;
160errout:
161 tcf_exts_destroy(&e);
162 return err;
163}
164
165static int basic_change(struct net *net, struct sk_buff *in_skb,
166 struct tcf_proto *tp, unsigned long base, u32 handle,
167 struct nlattr **tca, unsigned long *arg, bool ovr)
168{
169 int err;
170 struct basic_head *head = rtnl_dereference(tp->root);
171 struct nlattr *tb[TCA_BASIC_MAX + 1];
172 struct basic_filter *fold = (struct basic_filter *) *arg;
173 struct basic_filter *fnew;
174
175 if (tca[TCA_OPTIONS] == NULL)
176 return -EINVAL;
177
178 err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
179 basic_policy);
180 if (err < 0)
181 return err;
182
183 if (fold != NULL) {
184 if (handle && fold->handle != handle)
185 return -EINVAL;
186 }
187
188 fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
189 if (!fnew)
190 return -ENOBUFS;
191
192 tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
193 err = -EINVAL;
194 if (handle) {
195 fnew->handle = handle;
196 } else if (fold) {
197 fnew->handle = fold->handle;
198 } else {
199 unsigned int i = 0x80000000;
200 do {
201 if (++head->hgenerator == 0x7FFFFFFF)
202 head->hgenerator = 1;
203 } while (--i > 0 && basic_get(tp, head->hgenerator));
204
205 if (i <= 0) {
206 pr_err("Insufficient number of handles\n");
207 goto errout;
208 }
209
210 fnew->handle = head->hgenerator;
211 }
212
213 err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
214 if (err < 0)
215 goto errout;
216
217 *arg = (unsigned long)fnew;
218
219 if (fold) {
220 list_replace_rcu(&fold->link, &fnew->link);
221 tcf_unbind_filter(tp, &fold->res);
222 call_rcu(&fold->rcu, basic_delete_filter);
223 } else {
224 list_add_rcu(&fnew->link, &head->flist);
225 }
226
227 return 0;
228errout:
229 kfree(fnew);
230 return err;
231}
232
233static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
234{
235 struct basic_head *head = rtnl_dereference(tp->root);
236 struct basic_filter *f;
237
238 list_for_each_entry(f, &head->flist, link) {
239 if (arg->count < arg->skip)
240 goto skip;
241
242 if (arg->fn(tp, (unsigned long) f, arg) < 0) {
243 arg->stop = 1;
244 break;
245 }
246skip:
247 arg->count++;
248 }
249}
250
251static int basic_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
252 struct sk_buff *skb, struct tcmsg *t)
253{
254 struct basic_filter *f = (struct basic_filter *) fh;
255 struct nlattr *nest;
256
257 if (f == NULL)
258 return skb->len;
259
260 t->tcm_handle = f->handle;
261
262 nest = nla_nest_start(skb, TCA_OPTIONS);
263 if (nest == NULL)
264 goto nla_put_failure;
265
266 if (f->res.classid &&
267 nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
268 goto nla_put_failure;
269
270 if (tcf_exts_dump(skb, &f->exts) < 0 ||
271 tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
272 goto nla_put_failure;
273
274 nla_nest_end(skb, nest);
275
276 if (tcf_exts_dump_stats(skb, &f->exts) < 0)
277 goto nla_put_failure;
278
279 return skb->len;
280
281nla_put_failure:
282 nla_nest_cancel(skb, nest);
283 return -1;
284}
285
286static struct tcf_proto_ops cls_basic_ops __read_mostly = {
287 .kind = "basic",
288 .classify = basic_classify,
289 .init = basic_init,
290 .destroy = basic_destroy,
291 .get = basic_get,
292 .change = basic_change,
293 .delete = basic_delete,
294 .walk = basic_walk,
295 .dump = basic_dump,
296 .owner = THIS_MODULE,
297};
298
299static int __init init_basic(void)
300{
301 return register_tcf_proto_ops(&cls_basic_ops);
302}
303
304static void __exit exit_basic(void)
305{
306 unregister_tcf_proto_ops(&cls_basic_ops);
307}
308
309module_init(init_basic)
310module_exit(exit_basic)
311MODULE_LICENSE("GPL");
312
313
