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8#include <linux/types.h>
9#include <linux/kernel.h>
10#include <linux/string.h>
11#include <linux/errno.h>
12#include <linux/skbuff.h>
13#include <linux/rtnetlink.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <net/netlink.h>
17#include <net/pkt_sched.h>
18#include <net/pkt_cls.h>
19#include <linux/tc_act/tc_gact.h>
20#include <net/tc_act/tc_gact.h>
21
22static unsigned int gact_net_id;
23static struct tc_action_ops act_gact_ops;
24
25#ifdef CONFIG_GACT_PROB
26static int gact_net_rand(struct tcf_gact *gact)
27{
28 smp_rmb();
29 if (prandom_u32() % gact->tcfg_pval)
30 return gact->tcf_action;
31 return gact->tcfg_paction;
32}
33
34static int gact_determ(struct tcf_gact *gact)
35{
36 u32 pack = atomic_inc_return(&gact->packets);
37
38 smp_rmb();
39 if (pack % gact->tcfg_pval)
40 return gact->tcf_action;
41 return gact->tcfg_paction;
42}
43
44typedef int (*g_rand)(struct tcf_gact *gact);
45static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ };
46#endif
47
48static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
49 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) },
50 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) },
51};
52
53static int tcf_gact_init(struct net *net, struct nlattr *nla,
54 struct nlattr *est, struct tc_action **a,
55 int ovr, int bind, bool rtnl_held,
56 struct tcf_proto *tp, u32 flags,
57 struct netlink_ext_ack *extack)
58{
59 struct tc_action_net *tn = net_generic(net, gact_net_id);
60 struct nlattr *tb[TCA_GACT_MAX + 1];
61 struct tcf_chain *goto_ch = NULL;
62 struct tc_gact *parm;
63 struct tcf_gact *gact;
64 int ret = 0;
65 u32 index;
66 int err;
67#ifdef CONFIG_GACT_PROB
68 struct tc_gact_p *p_parm = NULL;
69#endif
70
71 if (nla == NULL)
72 return -EINVAL;
73
74 err = nla_parse_nested_deprecated(tb, TCA_GACT_MAX, nla, gact_policy,
75 NULL);
76 if (err < 0)
77 return err;
78
79 if (tb[TCA_GACT_PARMS] == NULL)
80 return -EINVAL;
81 parm = nla_data(tb[TCA_GACT_PARMS]);
82 index = parm->index;
83
84#ifndef CONFIG_GACT_PROB
85 if (tb[TCA_GACT_PROB] != NULL)
86 return -EOPNOTSUPP;
87#else
88 if (tb[TCA_GACT_PROB]) {
89 p_parm = nla_data(tb[TCA_GACT_PROB]);
90 if (p_parm->ptype >= MAX_RAND)
91 return -EINVAL;
92 if (TC_ACT_EXT_CMP(p_parm->paction, TC_ACT_GOTO_CHAIN)) {
93 NL_SET_ERR_MSG(extack,
94 "goto chain not allowed on fallback");
95 return -EINVAL;
96 }
97 }
98#endif
99
100 err = tcf_idr_check_alloc(tn, &index, a, bind);
101 if (!err) {
102 ret = tcf_idr_create_from_flags(tn, index, est, a,
103 &act_gact_ops, bind, flags);
104 if (ret) {
105 tcf_idr_cleanup(tn, index);
106 return ret;
107 }
108 ret = ACT_P_CREATED;
109 } else if (err > 0) {
110 if (bind)
111 return 0;
112 if (!ovr) {
113 tcf_idr_release(*a, bind);
114 return -EEXIST;
115 }
116 } else {
117 return err;
118 }
119
120 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
121 if (err < 0)
122 goto release_idr;
123 gact = to_gact(*a);
124
125 spin_lock_bh(&gact->tcf_lock);
126 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
127#ifdef CONFIG_GACT_PROB
128 if (p_parm) {
129 gact->tcfg_paction = p_parm->paction;
130 gact->tcfg_pval = max_t(u16, 1, p_parm->pval);
131
132
133
134 smp_wmb();
135 gact->tcfg_ptype = p_parm->ptype;
136 }
137#endif
138 spin_unlock_bh(&gact->tcf_lock);
139
140 if (goto_ch)
141 tcf_chain_put_by_act(goto_ch);
142
143 if (ret == ACT_P_CREATED)
144 tcf_idr_insert(tn, *a);
145 return ret;
146release_idr:
147 tcf_idr_release(*a, bind);
148 return err;
149}
150
151static int tcf_gact_act(struct sk_buff *skb, const struct tc_action *a,
152 struct tcf_result *res)
153{
154 struct tcf_gact *gact = to_gact(a);
155 int action = READ_ONCE(gact->tcf_action);
156
157#ifdef CONFIG_GACT_PROB
158 {
159 u32 ptype = READ_ONCE(gact->tcfg_ptype);
160
161 if (ptype)
162 action = gact_rand[ptype](gact);
163 }
164#endif
165 tcf_action_update_bstats(&gact->common, skb);
166 if (action == TC_ACT_SHOT)
167 tcf_action_inc_drop_qstats(&gact->common);
168
169 tcf_lastuse_update(&gact->tcf_tm);
170
171 return action;
172}
173
174static void tcf_gact_stats_update(struct tc_action *a, u64 bytes, u32 packets,
175 u64 lastuse, bool hw)
176{
177 struct tcf_gact *gact = to_gact(a);
178 int action = READ_ONCE(gact->tcf_action);
179 struct tcf_t *tm = &gact->tcf_tm;
180
181 tcf_action_update_stats(a, bytes, packets, action == TC_ACT_SHOT, hw);
182 tm->lastuse = max_t(u64, tm->lastuse, lastuse);
183}
184
185static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a,
186 int bind, int ref)
187{
188 unsigned char *b = skb_tail_pointer(skb);
189 struct tcf_gact *gact = to_gact(a);
190 struct tc_gact opt = {
191 .index = gact->tcf_index,
192 .refcnt = refcount_read(&gact->tcf_refcnt) - ref,
193 .bindcnt = atomic_read(&gact->tcf_bindcnt) - bind,
194 };
195 struct tcf_t t;
196
197 spin_lock_bh(&gact->tcf_lock);
198 opt.action = gact->tcf_action;
199 if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt))
200 goto nla_put_failure;
201#ifdef CONFIG_GACT_PROB
202 if (gact->tcfg_ptype) {
203 struct tc_gact_p p_opt = {
204 .paction = gact->tcfg_paction,
205 .pval = gact->tcfg_pval,
206 .ptype = gact->tcfg_ptype,
207 };
208
209 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt))
210 goto nla_put_failure;
211 }
212#endif
213 tcf_tm_dump(&t, &gact->tcf_tm);
214 if (nla_put_64bit(skb, TCA_GACT_TM, sizeof(t), &t, TCA_GACT_PAD))
215 goto nla_put_failure;
216 spin_unlock_bh(&gact->tcf_lock);
217
218 return skb->len;
219
220nla_put_failure:
221 spin_unlock_bh(&gact->tcf_lock);
222 nlmsg_trim(skb, b);
223 return -1;
224}
225
226static int tcf_gact_walker(struct net *net, struct sk_buff *skb,
227 struct netlink_callback *cb, int type,
228 const struct tc_action_ops *ops,
229 struct netlink_ext_ack *extack)
230{
231 struct tc_action_net *tn = net_generic(net, gact_net_id);
232
233 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
234}
235
236static int tcf_gact_search(struct net *net, struct tc_action **a, u32 index)
237{
238 struct tc_action_net *tn = net_generic(net, gact_net_id);
239
240 return tcf_idr_search(tn, a, index);
241}
242
243static size_t tcf_gact_get_fill_size(const struct tc_action *act)
244{
245 size_t sz = nla_total_size(sizeof(struct tc_gact));
246
247#ifdef CONFIG_GACT_PROB
248 if (to_gact(act)->tcfg_ptype)
249
250 sz += nla_total_size(sizeof(struct tc_gact_p));
251#endif
252
253 return sz;
254}
255
256static struct tc_action_ops act_gact_ops = {
257 .kind = "gact",
258 .id = TCA_ID_GACT,
259 .owner = THIS_MODULE,
260 .act = tcf_gact_act,
261 .stats_update = tcf_gact_stats_update,
262 .dump = tcf_gact_dump,
263 .init = tcf_gact_init,
264 .walk = tcf_gact_walker,
265 .lookup = tcf_gact_search,
266 .get_fill_size = tcf_gact_get_fill_size,
267 .size = sizeof(struct tcf_gact),
268};
269
270static __net_init int gact_init_net(struct net *net)
271{
272 struct tc_action_net *tn = net_generic(net, gact_net_id);
273
274 return tc_action_net_init(net, tn, &act_gact_ops);
275}
276
277static void __net_exit gact_exit_net(struct list_head *net_list)
278{
279 tc_action_net_exit(net_list, gact_net_id);
280}
281
282static struct pernet_operations gact_net_ops = {
283 .init = gact_init_net,
284 .exit_batch = gact_exit_net,
285 .id = &gact_net_id,
286 .size = sizeof(struct tc_action_net),
287};
288
289MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
290MODULE_DESCRIPTION("Generic Classifier actions");
291MODULE_LICENSE("GPL");
292
293static int __init gact_init_module(void)
294{
295#ifdef CONFIG_GACT_PROB
296 pr_info("GACT probability on\n");
297#else
298 pr_info("GACT probability NOT on\n");
299#endif
300
301 return tcf_register_action(&act_gact_ops, &gact_net_ops);
302}
303
304static void __exit gact_cleanup_module(void)
305{
306 tcf_unregister_action(&act_gact_ops, &gact_net_ops);
307}
308
309module_init(gact_init_module);
310module_exit(gact_cleanup_module);
311
