1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * net/sched/act_simple.c Simple example of an action
5 * Authors: Jamal Hadi Salim (2005-8)
8 #include <linux/module.h>
9 #include <linux/slab.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/skbuff.h>
13 #include <linux/rtnetlink.h>
14 #include <net/netlink.h>
15 #include <net/pkt_sched.h>
16 #include <net/pkt_cls.h>
18 #include <linux/tc_act/tc_defact.h>
19 #include <net/tc_act/tc_defact.h>
21 static unsigned int simp_net_id;
22 static struct tc_action_ops act_simp_ops;
24 #define SIMP_MAX_DATA 32
25 static int tcf_simp_act(struct sk_buff *skb, const struct tc_action *a,
26 struct tcf_result *res)
28 struct tcf_defact *d = to_defact(a);
30 spin_lock(&d->tcf_lock);
31 tcf_lastuse_update(&d->tcf_tm);
32 bstats_update(&d->tcf_bstats, skb);
34 /* print policy string followed by _ then packet count
35 * Example if this was the 3rd packet and the string was "hello"
36 * then it would look like "hello_3" (without quotes)
38 pr_info("simple: %s_%d\n",
39 (char *)d->tcfd_defdata, d->tcf_bstats.packets);
40 spin_unlock(&d->tcf_lock);
44 static void tcf_simp_release(struct tc_action *a)
46 struct tcf_defact *d = to_defact(a);
47 kfree(d->tcfd_defdata);
50 static int alloc_defdata(struct tcf_defact *d, const struct nlattr *defdata)
52 d->tcfd_defdata = kzalloc(SIMP_MAX_DATA, GFP_KERNEL);
53 if (unlikely(!d->tcfd_defdata))
55 nla_strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
59 static int reset_policy(struct tc_action *a, const struct nlattr *defdata,
60 struct tc_defact *p, struct tcf_proto *tp,
61 struct netlink_ext_ack *extack)
63 struct tcf_chain *goto_ch = NULL;
67 err = tcf_action_check_ctrlact(p->action, tp, &goto_ch, extack);
71 spin_lock_bh(&d->tcf_lock);
72 goto_ch = tcf_action_set_ctrlact(a, p->action, goto_ch);
73 memset(d->tcfd_defdata, 0, SIMP_MAX_DATA);
74 nla_strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
75 spin_unlock_bh(&d->tcf_lock);
77 tcf_chain_put_by_act(goto_ch);
81 static const struct nla_policy simple_policy[TCA_DEF_MAX + 1] = {
82 [TCA_DEF_PARMS] = { .len = sizeof(struct tc_defact) },
83 [TCA_DEF_DATA] = { .type = NLA_STRING, .len = SIMP_MAX_DATA },
86 static int tcf_simp_init(struct net *net, struct nlattr *nla,
87 struct nlattr *est, struct tc_action **a,
88 int ovr, int bind, bool rtnl_held,
89 struct tcf_proto *tp, struct netlink_ext_ack *extack)
91 struct tc_action_net *tn = net_generic(net, simp_net_id);
92 struct nlattr *tb[TCA_DEF_MAX + 1];
93 struct tcf_chain *goto_ch = NULL;
94 struct tc_defact *parm;
103 err = nla_parse_nested_deprecated(tb, TCA_DEF_MAX, nla, simple_policy,
108 if (tb[TCA_DEF_PARMS] == NULL)
111 parm = nla_data(tb[TCA_DEF_PARMS]);
113 err = tcf_idr_check_alloc(tn, &index, a, bind);
120 if (tb[TCA_DEF_DATA] == NULL) {
122 tcf_idr_release(*a, bind);
124 tcf_idr_cleanup(tn, index);
129 ret = tcf_idr_create(tn, index, est, a,
130 &act_simp_ops, bind, false);
132 tcf_idr_cleanup(tn, index);
137 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch,
142 err = alloc_defdata(d, tb[TCA_DEF_DATA]);
146 tcf_action_set_ctrlact(*a, parm->action, goto_ch);
154 err = reset_policy(*a, tb[TCA_DEF_DATA], parm, tp, extack);
162 tcf_chain_put_by_act(goto_ch);
164 tcf_idr_release(*a, bind);
168 static int tcf_simp_dump(struct sk_buff *skb, struct tc_action *a,
171 unsigned char *b = skb_tail_pointer(skb);
172 struct tcf_defact *d = to_defact(a);
173 struct tc_defact opt = {
174 .index = d->tcf_index,
175 .refcnt = refcount_read(&d->tcf_refcnt) - ref,
176 .bindcnt = atomic_read(&d->tcf_bindcnt) - bind,
180 spin_lock_bh(&d->tcf_lock);
181 opt.action = d->tcf_action;
182 if (nla_put(skb, TCA_DEF_PARMS, sizeof(opt), &opt) ||
183 nla_put_string(skb, TCA_DEF_DATA, d->tcfd_defdata))
184 goto nla_put_failure;
186 tcf_tm_dump(&t, &d->tcf_tm);
187 if (nla_put_64bit(skb, TCA_DEF_TM, sizeof(t), &t, TCA_DEF_PAD))
188 goto nla_put_failure;
189 spin_unlock_bh(&d->tcf_lock);
194 spin_unlock_bh(&d->tcf_lock);
199 static int tcf_simp_walker(struct net *net, struct sk_buff *skb,
200 struct netlink_callback *cb, int type,
201 const struct tc_action_ops *ops,
202 struct netlink_ext_ack *extack)
204 struct tc_action_net *tn = net_generic(net, simp_net_id);
206 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
209 static int tcf_simp_search(struct net *net, struct tc_action **a, u32 index)
211 struct tc_action_net *tn = net_generic(net, simp_net_id);
213 return tcf_idr_search(tn, a, index);
216 static struct tc_action_ops act_simp_ops = {
219 .owner = THIS_MODULE,
221 .dump = tcf_simp_dump,
222 .cleanup = tcf_simp_release,
223 .init = tcf_simp_init,
224 .walk = tcf_simp_walker,
225 .lookup = tcf_simp_search,
226 .size = sizeof(struct tcf_defact),
229 static __net_init int simp_init_net(struct net *net)
231 struct tc_action_net *tn = net_generic(net, simp_net_id);
233 return tc_action_net_init(net, tn, &act_simp_ops);
236 static void __net_exit simp_exit_net(struct list_head *net_list)
238 tc_action_net_exit(net_list, simp_net_id);
241 static struct pernet_operations simp_net_ops = {
242 .init = simp_init_net,
243 .exit_batch = simp_exit_net,
245 .size = sizeof(struct tc_action_net),
248 MODULE_AUTHOR("Jamal Hadi Salim(2005)");
249 MODULE_DESCRIPTION("Simple example action");
250 MODULE_LICENSE("GPL");
252 static int __init simp_init_module(void)
254 int ret = tcf_register_action(&act_simp_ops, &simp_net_ops);
256 pr_info("Simple TC action Loaded\n");
260 static void __exit simp_cleanup_module(void)
262 tcf_unregister_action(&act_simp_ops, &simp_net_ops);
265 module_init(simp_init_module);
266 module_exit(simp_cleanup_module);