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 unsigned int pedit_net_id;
29 static struct tc_action_ops act_pedit_ops;
31 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
32 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
35 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
36 struct nlattr *est, struct tc_action **a,
39 struct tc_action_net *tn = net_generic(net, pedit_net_id);
40 struct nlattr *tb[TCA_PEDIT_MAX + 1];
41 struct tc_pedit *parm;
44 struct tc_pedit_key *keys = NULL;
50 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
54 if (tb[TCA_PEDIT_PARMS] == NULL)
56 parm = nla_data(tb[TCA_PEDIT_PARMS]);
57 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
58 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
61 if (!tcf_hash_check(tn, parm->index, a, bind)) {
64 ret = tcf_hash_create(tn, parm->index, est, a,
65 &act_pedit_ops, bind, false);
69 keys = kmalloc(ksize, GFP_KERNEL);
71 tcf_hash_cleanup(*a, est);
78 tcf_hash_release(*a, bind);
82 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
83 keys = kmalloc(ksize, GFP_KERNEL);
89 spin_lock_bh(&p->tcf_lock);
90 p->tcfp_flags = parm->flags;
91 p->tcf_action = parm->action;
95 p->tcfp_nkeys = parm->nkeys;
97 memcpy(p->tcfp_keys, parm->keys, ksize);
98 spin_unlock_bh(&p->tcf_lock);
99 if (ret == ACT_P_CREATED)
100 tcf_hash_insert(tn, *a);
104 static void tcf_pedit_cleanup(struct tc_action *a, int bind)
106 struct tcf_pedit *p = to_pedit(a);
107 struct tc_pedit_key *keys = p->tcfp_keys;
111 static bool offset_valid(struct sk_buff *skb, int offset)
113 if (offset > 0 && offset > skb->len)
116 if (offset < 0 && -offset > skb_headroom(skb))
122 static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
123 struct tcf_result *res)
125 struct tcf_pedit *p = to_pedit(a);
129 if (skb_unclone(skb, GFP_ATOMIC))
130 return p->tcf_action;
132 off = skb_network_offset(skb);
134 spin_lock(&p->tcf_lock);
136 tcf_lastuse_update(&p->tcf_tm);
138 if (p->tcfp_nkeys > 0) {
139 struct tc_pedit_key *tkey = p->tcfp_keys;
141 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
143 int offset = tkey->off;
148 if (!offset_valid(skb, off + tkey->at)) {
149 pr_info("tc filter pedit 'at' offset %d out of bounds\n",
153 d = skb_header_pointer(skb, off + tkey->at, 1,
157 offset += (*d & tkey->offmask) >> tkey->shift;
161 pr_info("tc filter pedit"
162 " offset must be on 32 bit boundaries\n");
166 if (!offset_valid(skb, off + offset)) {
167 pr_info("tc filter pedit offset %d out of bounds\n",
172 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
175 /* just do it, baby */
176 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
178 skb_store_bits(skb, off + offset, ptr, 4);
183 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
186 p->tcf_qstats.overlimits++;
188 bstats_update(&p->tcf_bstats, skb);
189 spin_unlock(&p->tcf_lock);
190 return p->tcf_action;
193 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
196 unsigned char *b = skb_tail_pointer(skb);
197 struct tcf_pedit *p = to_pedit(a);
198 struct tc_pedit *opt;
202 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
204 /* netlink spinlocks held above us - must use ATOMIC */
205 opt = kzalloc(s, GFP_ATOMIC);
209 memcpy(opt->keys, p->tcfp_keys,
210 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
211 opt->index = p->tcf_index;
212 opt->nkeys = p->tcfp_nkeys;
213 opt->flags = p->tcfp_flags;
214 opt->action = p->tcf_action;
215 opt->refcnt = p->tcf_refcnt - ref;
216 opt->bindcnt = p->tcf_bindcnt - bind;
218 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
219 goto nla_put_failure;
221 tcf_tm_dump(&t, &p->tcf_tm);
222 if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
223 goto nla_put_failure;
234 static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
235 struct netlink_callback *cb, int type,
236 const struct tc_action_ops *ops)
238 struct tc_action_net *tn = net_generic(net, pedit_net_id);
240 return tcf_generic_walker(tn, skb, cb, type, ops);
243 static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index)
245 struct tc_action_net *tn = net_generic(net, pedit_net_id);
247 return tcf_hash_search(tn, a, index);
250 static struct tc_action_ops act_pedit_ops = {
252 .type = TCA_ACT_PEDIT,
253 .owner = THIS_MODULE,
255 .dump = tcf_pedit_dump,
256 .cleanup = tcf_pedit_cleanup,
257 .init = tcf_pedit_init,
258 .walk = tcf_pedit_walker,
259 .lookup = tcf_pedit_search,
260 .size = sizeof(struct tcf_pedit),
263 static __net_init int pedit_init_net(struct net *net)
265 struct tc_action_net *tn = net_generic(net, pedit_net_id);
267 return tc_action_net_init(tn, &act_pedit_ops, PEDIT_TAB_MASK);
270 static void __net_exit pedit_exit_net(struct net *net)
272 struct tc_action_net *tn = net_generic(net, pedit_net_id);
274 tc_action_net_exit(tn);
277 static struct pernet_operations pedit_net_ops = {
278 .init = pedit_init_net,
279 .exit = pedit_exit_net,
281 .size = sizeof(struct tc_action_net),
284 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
285 MODULE_DESCRIPTION("Generic Packet Editor actions");
286 MODULE_LICENSE("GPL");
288 static int __init pedit_init_module(void)
290 return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
293 static void __exit pedit_cleanup_module(void)
295 tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
298 module_init(pedit_init_module);
299 module_exit(pedit_cleanup_module);