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13#include <linux/types.h>
14#include <linux/kernel.h>
15#include <linux/string.h>
16#include <linux/errno.h>
17#include <linux/skbuff.h>
18#include <linux/rtnetlink.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <net/netlink.h>
22#include <net/pkt_sched.h>
23#include <linux/tc_act/tc_gact.h>
24#include <net/tc_act/tc_gact.h>
25
26#define GACT_TAB_MASK 15
27static struct tcf_common *tcf_gact_ht[GACT_TAB_MASK + 1];
28static u32 gact_idx_gen;
29static DEFINE_RWLOCK(gact_lock);
30
31static struct tcf_hashinfo gact_hash_info = {
32 .htab = tcf_gact_ht,
33 .hmask = GACT_TAB_MASK,
34 .lock = &gact_lock,
35};
36
37#ifdef CONFIG_GACT_PROB
38static int gact_net_rand(struct tcf_gact *gact)
39{
40 if (!gact->tcfg_pval || net_random() % gact->tcfg_pval)
41 return gact->tcf_action;
42 return gact->tcfg_paction;
43}
44
45static int gact_determ(struct tcf_gact *gact)
46{
47 if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval)
48 return gact->tcf_action;
49 return gact->tcfg_paction;
50}
51
52typedef int (*g_rand)(struct tcf_gact *gact);
53static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ };
54#endif
55
56static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
57 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) },
58 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) },
59};
60
61static int tcf_gact_init(struct nlattr *nla, struct nlattr *est,
62 struct tc_action *a, int ovr, int bind)
63{
64 struct nlattr *tb[TCA_GACT_MAX + 1];
65 struct tc_gact *parm;
66 struct tcf_gact *gact;
67 struct tcf_common *pc;
68 int ret = 0;
69 int err;
70
71 if (nla == NULL)
72 return -EINVAL;
73
74 err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy);
75 if (err < 0)
76 return err;
77
78 if (tb[TCA_GACT_PARMS] == NULL)
79 return -EINVAL;
80 parm = nla_data(tb[TCA_GACT_PARMS]);
81
82#ifndef CONFIG_GACT_PROB
83 if (tb[TCA_GACT_PROB] != NULL)
84 return -EOPNOTSUPP;
85#endif
86
87 pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info);
88 if (!pc) {
89 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact),
90 bind, &gact_idx_gen, &gact_hash_info);
91 if (IS_ERR(pc))
92 return PTR_ERR(pc);
93 ret = ACT_P_CREATED;
94 } else {
95 if (!ovr) {
96 tcf_hash_release(pc, bind, &gact_hash_info);
97 return -EEXIST;
98 }
99 }
100
101 gact = to_gact(pc);
102
103 spin_lock_bh(&gact->tcf_lock);
104 gact->tcf_action = parm->action;
105#ifdef CONFIG_GACT_PROB
106 if (tb[TCA_GACT_PROB] != NULL) {
107 struct tc_gact_p *p_parm = nla_data(tb[TCA_GACT_PROB]);
108 gact->tcfg_paction = p_parm->paction;
109 gact->tcfg_pval = p_parm->pval;
110 gact->tcfg_ptype = p_parm->ptype;
111 }
112#endif
113 spin_unlock_bh(&gact->tcf_lock);
114 if (ret == ACT_P_CREATED)
115 tcf_hash_insert(pc, &gact_hash_info);
116 return ret;
117}
118
119static int tcf_gact_cleanup(struct tc_action *a, int bind)
120{
121 struct tcf_gact *gact = a->priv;
122
123 if (gact)
124 return tcf_hash_release(&gact->common, bind, &gact_hash_info);
125 return 0;
126}
127
128static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
129{
130 struct tcf_gact *gact = a->priv;
131 int action = TC_ACT_SHOT;
132
133 spin_lock(&gact->tcf_lock);
134#ifdef CONFIG_GACT_PROB
135 if (gact->tcfg_ptype && gact_rand[gact->tcfg_ptype] != NULL)
136 action = gact_rand[gact->tcfg_ptype](gact);
137 else
138 action = gact->tcf_action;
139#else
140 action = gact->tcf_action;
141#endif
142 gact->tcf_bstats.bytes += qdisc_pkt_len(skb);
143 gact->tcf_bstats.packets++;
144 if (action == TC_ACT_SHOT)
145 gact->tcf_qstats.drops++;
146 gact->tcf_tm.lastuse = jiffies;
147 spin_unlock(&gact->tcf_lock);
148
149 return action;
150}
151
152static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
153{
154 unsigned char *b = skb_tail_pointer(skb);
155 struct tcf_gact *gact = a->priv;
156 struct tc_gact opt = {
157 .index = gact->tcf_index,
158 .refcnt = gact->tcf_refcnt - ref,
159 .bindcnt = gact->tcf_bindcnt - bind,
160 .action = gact->tcf_action,
161 };
162 struct tcf_t t;
163
164 NLA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt);
165#ifdef CONFIG_GACT_PROB
166 if (gact->tcfg_ptype) {
167 struct tc_gact_p p_opt = {
168 .paction = gact->tcfg_paction,
169 .pval = gact->tcfg_pval,
170 .ptype = gact->tcfg_ptype,
171 };
172
173 NLA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt);
174 }
175#endif
176 t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install);
177 t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse);
178 t.expires = jiffies_to_clock_t(gact->tcf_tm.expires);
179 NLA_PUT(skb, TCA_GACT_TM, sizeof(t), &t);
180 return skb->len;
181
182nla_put_failure:
183 nlmsg_trim(skb, b);
184 return -1;
185}
186
187static struct tc_action_ops act_gact_ops = {
188 .kind = "gact",
189 .hinfo = &gact_hash_info,
190 .type = TCA_ACT_GACT,
191 .capab = TCA_CAP_NONE,
192 .owner = THIS_MODULE,
193 .act = tcf_gact,
194 .dump = tcf_gact_dump,
195 .cleanup = tcf_gact_cleanup,
196 .lookup = tcf_hash_search,
197 .init = tcf_gact_init,
198 .walk = tcf_generic_walker
199};
200
201MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
202MODULE_DESCRIPTION("Generic Classifier actions");
203MODULE_LICENSE("GPL");
204
205static int __init gact_init_module(void)
206{
207#ifdef CONFIG_GACT_PROB
208 pr_info("GACT probability on\n");
209#else
210 pr_info("GACT probability NOT on\n");
211#endif
212 return tcf_register_action(&act_gact_ops);
213}
214
215static void __exit gact_cleanup_module(void)
216{
217 tcf_unregister_action(&act_gact_ops);
218}
219
220module_init(gact_init_module);
221module_exit(gact_cleanup_module);
222
