2 * net/sched/act_pedit.c Generic packet editor
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.
9 * Authors: Jamal Hadi Salim (2002-4)
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/errno.h>
16 #include <linux/skbuff.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <net/netlink.h>
22 #include <net/pkt_sched.h>
23 #include <linux/tc_act/tc_pedit.h>
24 #include <net/tc_act/tc_pedit.h>
26 #define PEDIT_TAB_MASK 15
28 static int pedit_net_id;
30 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
31 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
34 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
35 struct nlattr *est, struct tc_action *a,
38 struct tc_action_net *tn = net_generic(net, pedit_net_id);
39 struct nlattr *tb[TCA_PEDIT_MAX + 1];
40 struct tc_pedit *parm;
43 struct tc_pedit_key *keys = NULL;
49 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
53 if (tb[TCA_PEDIT_PARMS] == NULL)
55 parm = nla_data(tb[TCA_PEDIT_PARMS]);
56 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
57 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
60 if (!tcf_hash_check(tn, parm->index, a, bind)) {
63 ret = tcf_hash_create(tn, parm->index, est, a,
64 sizeof(*p), bind, false);
68 keys = kmalloc(ksize, GFP_KERNEL);
70 tcf_hash_cleanup(a, est);
77 tcf_hash_release(a, bind);
81 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
82 keys = kmalloc(ksize, GFP_KERNEL);
88 spin_lock_bh(&p->tcf_lock);
89 p->tcfp_flags = parm->flags;
90 p->tcf_action = parm->action;
94 p->tcfp_nkeys = parm->nkeys;
96 memcpy(p->tcfp_keys, parm->keys, ksize);
97 spin_unlock_bh(&p->tcf_lock);
98 if (ret == ACT_P_CREATED)
99 tcf_hash_insert(tn, a);
103 static void tcf_pedit_cleanup(struct tc_action *a, int bind)
105 struct tcf_pedit *p = a->priv;
106 struct tc_pedit_key *keys = p->tcfp_keys;
110 static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
111 struct tcf_result *res)
113 struct tcf_pedit *p = a->priv;
117 if (skb_unclone(skb, GFP_ATOMIC))
118 return p->tcf_action;
120 off = skb_network_offset(skb);
122 spin_lock(&p->tcf_lock);
124 p->tcf_tm.lastuse = jiffies;
126 if (p->tcfp_nkeys > 0) {
127 struct tc_pedit_key *tkey = p->tcfp_keys;
129 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
131 int offset = tkey->off;
136 d = skb_header_pointer(skb, off + tkey->at, 1,
140 offset += (*d & tkey->offmask) >> tkey->shift;
144 pr_info("tc filter pedit"
145 " offset must be on 32 bit boundaries\n");
148 if (offset > 0 && offset > skb->len) {
149 pr_info("tc filter pedit"
150 " offset %d can't exceed pkt length %d\n",
155 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
158 /* just do it, baby */
159 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
161 skb_store_bits(skb, off + offset, ptr, 4);
166 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
169 p->tcf_qstats.overlimits++;
171 bstats_update(&p->tcf_bstats, skb);
172 spin_unlock(&p->tcf_lock);
173 return p->tcf_action;
176 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
179 unsigned char *b = skb_tail_pointer(skb);
180 struct tcf_pedit *p = a->priv;
181 struct tc_pedit *opt;
185 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
187 /* netlink spinlocks held above us - must use ATOMIC */
188 opt = kzalloc(s, GFP_ATOMIC);
192 memcpy(opt->keys, p->tcfp_keys,
193 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
194 opt->index = p->tcf_index;
195 opt->nkeys = p->tcfp_nkeys;
196 opt->flags = p->tcfp_flags;
197 opt->action = p->tcf_action;
198 opt->refcnt = p->tcf_refcnt - ref;
199 opt->bindcnt = p->tcf_bindcnt - bind;
201 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
202 goto nla_put_failure;
203 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
204 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
205 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
206 if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t))
207 goto nla_put_failure;
217 static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
218 struct netlink_callback *cb, int type,
221 struct tc_action_net *tn = net_generic(net, pedit_net_id);
223 return tcf_generic_walker(tn, skb, cb, type, a);
226 static int tcf_pedit_search(struct net *net, struct tc_action *a, u32 index)
228 struct tc_action_net *tn = net_generic(net, pedit_net_id);
230 return tcf_hash_search(tn, a, index);
233 static struct tc_action_ops act_pedit_ops = {
235 .type = TCA_ACT_PEDIT,
236 .owner = THIS_MODULE,
238 .dump = tcf_pedit_dump,
239 .cleanup = tcf_pedit_cleanup,
240 .init = tcf_pedit_init,
241 .walk = tcf_pedit_walker,
242 .lookup = tcf_pedit_search,
245 static __net_init int pedit_init_net(struct net *net)
247 struct tc_action_net *tn = net_generic(net, pedit_net_id);
249 return tc_action_net_init(tn, &act_pedit_ops, PEDIT_TAB_MASK);
252 static void __net_exit pedit_exit_net(struct net *net)
254 struct tc_action_net *tn = net_generic(net, pedit_net_id);
256 tc_action_net_exit(tn);
259 static struct pernet_operations pedit_net_ops = {
260 .init = pedit_init_net,
261 .exit = pedit_exit_net,
263 .size = sizeof(struct tc_action_net),
266 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
267 MODULE_DESCRIPTION("Generic Packet Editor actions");
268 MODULE_LICENSE("GPL");
270 static int __init pedit_init_module(void)
272 return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
275 static void __exit pedit_cleanup_module(void)
277 tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
280 module_init(pedit_init_module);
281 module_exit(pedit_cleanup_module);