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
28 static struct tcf_hashinfo pedit_hash_info;
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 nlattr *tb[TCA_PEDIT_MAX + 1];
39 struct tc_pedit *parm;
42 struct tc_pedit_key *keys = NULL;
48 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
52 if (tb[TCA_PEDIT_PARMS] == NULL)
54 parm = nla_data(tb[TCA_PEDIT_PARMS]);
55 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
56 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
59 if (!tcf_hash_check(parm->index, a, bind)) {
62 ret = tcf_hash_create(parm->index, est, a, sizeof(*p), bind);
66 keys = kmalloc(ksize, GFP_KERNEL);
68 tcf_hash_cleanup(a, est);
74 tcf_hash_release(a, bind);
80 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
81 keys = kmalloc(ksize, GFP_KERNEL);
87 spin_lock_bh(&p->tcf_lock);
88 p->tcfp_flags = parm->flags;
89 p->tcf_action = parm->action;
93 p->tcfp_nkeys = parm->nkeys;
95 memcpy(p->tcfp_keys, parm->keys, ksize);
96 spin_unlock_bh(&p->tcf_lock);
97 if (ret == ACT_P_CREATED)
102 static void tcf_pedit_cleanup(struct tc_action *a, int bind)
104 struct tcf_pedit *p = a->priv;
105 struct tc_pedit_key *keys = p->tcfp_keys;
109 static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
110 struct tcf_result *res)
112 struct tcf_pedit *p = a->priv;
116 if (skb_unclone(skb, GFP_ATOMIC))
117 return p->tcf_action;
119 off = skb_network_offset(skb);
121 spin_lock(&p->tcf_lock);
123 p->tcf_tm.lastuse = jiffies;
125 if (p->tcfp_nkeys > 0) {
126 struct tc_pedit_key *tkey = p->tcfp_keys;
128 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
130 int offset = tkey->off;
135 d = skb_header_pointer(skb, off + tkey->at, 1,
139 offset += (*d & tkey->offmask) >> tkey->shift;
143 pr_info("tc filter pedit"
144 " offset must be on 32 bit boundaries\n");
147 if (offset > 0 && offset > skb->len) {
148 pr_info("tc filter pedit"
149 " offset %d can't exceed pkt length %d\n",
154 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
157 /* just do it, baby */
158 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
160 skb_store_bits(skb, off + offset, ptr, 4);
165 skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
168 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
171 p->tcf_qstats.overlimits++;
173 bstats_update(&p->tcf_bstats, skb);
174 spin_unlock(&p->tcf_lock);
175 return p->tcf_action;
178 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
181 unsigned char *b = skb_tail_pointer(skb);
182 struct tcf_pedit *p = a->priv;
183 struct tc_pedit *opt;
187 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
189 /* netlink spinlocks held above us - must use ATOMIC */
190 opt = kzalloc(s, GFP_ATOMIC);
194 memcpy(opt->keys, p->tcfp_keys,
195 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
196 opt->index = p->tcf_index;
197 opt->nkeys = p->tcfp_nkeys;
198 opt->flags = p->tcfp_flags;
199 opt->action = p->tcf_action;
200 opt->refcnt = p->tcf_refcnt - ref;
201 opt->bindcnt = p->tcf_bindcnt - bind;
203 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
204 goto nla_put_failure;
205 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
206 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
207 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
208 if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t))
209 goto nla_put_failure;
219 static struct tc_action_ops act_pedit_ops = {
221 .hinfo = &pedit_hash_info,
222 .type = TCA_ACT_PEDIT,
223 .owner = THIS_MODULE,
225 .dump = tcf_pedit_dump,
226 .cleanup = tcf_pedit_cleanup,
227 .init = tcf_pedit_init,
230 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
231 MODULE_DESCRIPTION("Generic Packet Editor actions");
232 MODULE_LICENSE("GPL");
234 static int __init pedit_init_module(void)
236 int err = tcf_hashinfo_init(&pedit_hash_info, PEDIT_TAB_MASK);
239 return tcf_register_action(&act_pedit_ops);
242 static void __exit pedit_cleanup_module(void)
244 tcf_hashinfo_destroy(&pedit_hash_info);
245 tcf_unregister_action(&act_pedit_ops);
248 module_init(pedit_init_module);
249 module_exit(pedit_cleanup_module);