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);
87 tcf_hash_release(pc, bind, &pedit_hash_info);
93 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
94 keys = kmalloc(ksize, GFP_KERNEL);
100 spin_lock_bh(&p->tcf_lock);
101 p->tcfp_flags = parm->flags;
102 p->tcf_action = parm->action;
106 p->tcfp_nkeys = parm->nkeys;
108 memcpy(p->tcfp_keys, parm->keys, ksize);
109 spin_unlock_bh(&p->tcf_lock);
110 if (ret == ACT_P_CREATED)
111 tcf_hash_insert(pc, &pedit_hash_info);
115 static int tcf_pedit_cleanup(struct tc_action *a, int bind)
117 struct tcf_pedit *p = a->priv;
120 struct tc_pedit_key *keys = p->tcfp_keys;
121 if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
129 static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
130 struct tcf_result *res)
132 struct tcf_pedit *p = a->priv;
136 if (skb_unclone(skb, GFP_ATOMIC))
137 return p->tcf_action;
139 off = skb_network_offset(skb);
141 spin_lock(&p->tcf_lock);
143 p->tcf_tm.lastuse = jiffies;
145 if (p->tcfp_nkeys > 0) {
146 struct tc_pedit_key *tkey = p->tcfp_keys;
148 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
150 int offset = tkey->off;
155 d = skb_header_pointer(skb, off + tkey->at, 1,
159 offset += (*d & tkey->offmask) >> tkey->shift;
163 pr_info("tc filter pedit"
164 " offset must be on 32 bit boundaries\n");
167 if (offset > 0 && offset > skb->len) {
168 pr_info("tc filter pedit"
169 " offset %d can't exceed pkt length %d\n",
174 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
177 /* just do it, baby */
178 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
180 skb_store_bits(skb, off + offset, ptr, 4);
185 skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
188 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
191 p->tcf_qstats.overlimits++;
193 bstats_update(&p->tcf_bstats, skb);
194 spin_unlock(&p->tcf_lock);
195 return p->tcf_action;
198 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
201 unsigned char *b = skb_tail_pointer(skb);
202 struct tcf_pedit *p = a->priv;
203 struct tc_pedit *opt;
207 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
209 /* netlink spinlocks held above us - must use ATOMIC */
210 opt = kzalloc(s, GFP_ATOMIC);
214 memcpy(opt->keys, p->tcfp_keys,
215 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
216 opt->index = p->tcf_index;
217 opt->nkeys = p->tcfp_nkeys;
218 opt->flags = p->tcfp_flags;
219 opt->action = p->tcf_action;
220 opt->refcnt = p->tcf_refcnt - ref;
221 opt->bindcnt = p->tcf_bindcnt - bind;
223 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
224 goto nla_put_failure;
225 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
226 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
227 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
228 if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t))
229 goto nla_put_failure;
239 static struct tc_action_ops act_pedit_ops = {
241 .hinfo = &pedit_hash_info,
242 .type = TCA_ACT_PEDIT,
243 .capab = TCA_CAP_NONE,
244 .owner = THIS_MODULE,
246 .dump = tcf_pedit_dump,
247 .cleanup = tcf_pedit_cleanup,
248 .init = tcf_pedit_init,
251 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
252 MODULE_DESCRIPTION("Generic Packet Editor actions");
253 MODULE_LICENSE("GPL");
255 static int __init pedit_init_module(void)
257 return tcf_register_action(&act_pedit_ops);
260 static void __exit pedit_cleanup_module(void)
262 tcf_unregister_action(&act_pedit_ops);
265 module_init(pedit_init_module);
266 module_exit(pedit_cleanup_module);