2 * net/sched/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
27 static struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
28 static u32 pedit_idx_gen;
29 static DEFINE_RWLOCK(pedit_lock);
31 static struct tcf_hashinfo pedit_hash_info = {
33 .hmask = PEDIT_TAB_MASK,
37 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
38 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
41 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
42 struct nlattr *est, struct tc_action *a,
45 struct nlattr *tb[TCA_PEDIT_MAX + 1];
46 struct tc_pedit *parm;
49 struct tcf_common *pc;
50 struct tc_pedit_key *keys = NULL;
56 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
60 if (tb[TCA_PEDIT_PARMS] == NULL)
62 parm = nla_data(tb[TCA_PEDIT_PARMS]);
63 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
64 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
67 pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info);
71 pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind,
72 &pedit_idx_gen, &pedit_hash_info);
76 keys = kmalloc(ksize, GFP_KERNEL);
79 gen_kill_estimator(&pc->tcfc_bstats,
81 kfree_rcu(pc, tcfc_rcu);
88 tcf_hash_release(pc, bind, &pedit_hash_info);
91 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
92 keys = kmalloc(ksize, GFP_KERNEL);
98 spin_lock_bh(&p->tcf_lock);
99 p->tcfp_flags = parm->flags;
100 p->tcf_action = parm->action;
104 p->tcfp_nkeys = parm->nkeys;
106 memcpy(p->tcfp_keys, parm->keys, ksize);
107 spin_unlock_bh(&p->tcf_lock);
108 if (ret == ACT_P_CREATED)
109 tcf_hash_insert(pc, &pedit_hash_info);
113 static int tcf_pedit_cleanup(struct tc_action *a, int bind)
115 struct tcf_pedit *p = a->priv;
118 struct tc_pedit_key *keys = p->tcfp_keys;
119 if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
127 static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
128 struct tcf_result *res)
130 struct tcf_pedit *p = a->priv;
134 if (skb_cloned(skb) &&
135 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
136 return p->tcf_action;
138 off = skb_network_offset(skb);
140 spin_lock(&p->tcf_lock);
142 p->tcf_tm.lastuse = jiffies;
144 if (p->tcfp_nkeys > 0) {
145 struct tc_pedit_key *tkey = p->tcfp_keys;
147 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
149 int offset = tkey->off;
154 d = skb_header_pointer(skb, off + tkey->at, 1,
158 offset += (*d & tkey->offmask) >> tkey->shift;
162 pr_info("tc filter pedit"
163 " offset must be on 32 bit boundaries\n");
166 if (offset > 0 && offset > skb->len) {
167 pr_info("tc filter pedit"
168 " offset %d can't exceed pkt length %d\n",
173 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
176 /* just do it, baby */
177 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
179 skb_store_bits(skb, off + offset, ptr, 4);
184 skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
187 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
190 p->tcf_qstats.overlimits++;
192 bstats_update(&p->tcf_bstats, skb);
193 spin_unlock(&p->tcf_lock);
194 return p->tcf_action;
197 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
200 unsigned char *b = skb_tail_pointer(skb);
201 struct tcf_pedit *p = a->priv;
202 struct tc_pedit *opt;
206 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
208 /* netlink spinlocks held above us - must use ATOMIC */
209 opt = kzalloc(s, GFP_ATOMIC);
213 memcpy(opt->keys, p->tcfp_keys,
214 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
215 opt->index = p->tcf_index;
216 opt->nkeys = p->tcfp_nkeys;
217 opt->flags = p->tcfp_flags;
218 opt->action = p->tcf_action;
219 opt->refcnt = p->tcf_refcnt - ref;
220 opt->bindcnt = p->tcf_bindcnt - bind;
222 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
223 goto nla_put_failure;
224 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
225 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
226 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
227 if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t))
228 goto nla_put_failure;
238 static struct tc_action_ops act_pedit_ops = {
240 .hinfo = &pedit_hash_info,
241 .type = TCA_ACT_PEDIT,
242 .capab = TCA_CAP_NONE,
243 .owner = THIS_MODULE,
245 .dump = tcf_pedit_dump,
246 .cleanup = tcf_pedit_cleanup,
247 .lookup = tcf_hash_search,
248 .init = tcf_pedit_init,
249 .walk = tcf_generic_walker
252 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
253 MODULE_DESCRIPTION("Generic Packet Editor actions");
254 MODULE_LICENSE("GPL");
256 static int __init pedit_init_module(void)
258 return tcf_register_action(&act_pedit_ops);
261 static void __exit pedit_cleanup_module(void)
263 tcf_unregister_action(&act_pedit_ops);
266 module_init(pedit_init_module);
267 module_exit(pedit_cleanup_module);