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 <net/netlink.h>
21 #include <net/pkt_sched.h>
22 #include <linux/tc_act/tc_pedit.h>
23 #include <net/tc_act/tc_pedit.h>
25 #define PEDIT_TAB_MASK 15
26 static struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
27 static u32 pedit_idx_gen;
28 static DEFINE_RWLOCK(pedit_lock);
30 static struct tcf_hashinfo pedit_hash_info = {
32 .hmask = PEDIT_TAB_MASK,
36 static int tcf_pedit_init(struct nlattr *nla, struct nlattr *est,
37 struct tc_action *a, int ovr, int bind)
39 struct nlattr *tb[TCA_PEDIT_MAX + 1];
40 struct tc_pedit *parm;
43 struct tcf_common *pc;
44 struct tc_pedit_key *keys = NULL;
50 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, NULL);
54 if (tb[TCA_PEDIT_PARMS] == NULL ||
55 nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm))
57 parm = nla_data(tb[TCA_PEDIT_PARMS]);
58 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
59 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
62 pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info);
66 pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind,
67 &pedit_idx_gen, &pedit_hash_info);
71 keys = kmalloc(ksize, GFP_KERNEL);
80 tcf_hash_release(pc, bind, &pedit_hash_info);
83 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
84 keys = kmalloc(ksize, GFP_KERNEL);
90 spin_lock_bh(&p->tcf_lock);
91 p->tcfp_flags = parm->flags;
92 p->tcf_action = parm->action;
96 p->tcfp_nkeys = parm->nkeys;
98 memcpy(p->tcfp_keys, parm->keys, ksize);
99 spin_unlock_bh(&p->tcf_lock);
100 if (ret == ACT_P_CREATED)
101 tcf_hash_insert(pc, &pedit_hash_info);
105 static int tcf_pedit_cleanup(struct tc_action *a, int bind)
107 struct tcf_pedit *p = a->priv;
110 struct tc_pedit_key *keys = p->tcfp_keys;
111 if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
119 static int tcf_pedit(struct sk_buff *skb, struct tc_action *a,
120 struct tcf_result *res)
122 struct tcf_pedit *p = a->priv;
126 if (!(skb->tc_verd & TC_OK2MUNGE)) {
127 /* should we set skb->cloned? */
128 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
129 return p->tcf_action;
133 pptr = skb_network_header(skb);
135 spin_lock(&p->tcf_lock);
137 p->tcf_tm.lastuse = jiffies;
139 if (p->tcfp_nkeys > 0) {
140 struct tc_pedit_key *tkey = p->tcfp_keys;
142 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
144 int offset = tkey->off;
147 if (skb->len > tkey->at) {
148 char *j = pptr + tkey->at;
149 offset += ((*j & tkey->offmask) >>
157 printk("offset must be on 32 bit boundaries\n");
160 if (offset > 0 && offset > skb->len) {
161 printk("offset %d cant exceed pkt length %d\n",
166 ptr = (u32 *)(pptr+offset);
167 /* just do it, baby */
168 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
173 skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
176 printk("pedit BUG: index %d\n", p->tcf_index);
180 p->tcf_qstats.overlimits++;
182 p->tcf_bstats.bytes += skb->len;
183 p->tcf_bstats.packets++;
184 spin_unlock(&p->tcf_lock);
185 return p->tcf_action;
188 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
191 unsigned char *b = skb_tail_pointer(skb);
192 struct tcf_pedit *p = a->priv;
193 struct tc_pedit *opt;
197 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
199 /* netlink spinlocks held above us - must use ATOMIC */
200 opt = kzalloc(s, GFP_ATOMIC);
204 memcpy(opt->keys, p->tcfp_keys,
205 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
206 opt->index = p->tcf_index;
207 opt->nkeys = p->tcfp_nkeys;
208 opt->flags = p->tcfp_flags;
209 opt->action = p->tcf_action;
210 opt->refcnt = p->tcf_refcnt - ref;
211 opt->bindcnt = p->tcf_bindcnt - bind;
213 NLA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
214 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
215 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
216 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
217 NLA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
227 static struct tc_action_ops act_pedit_ops = {
229 .hinfo = &pedit_hash_info,
230 .type = TCA_ACT_PEDIT,
231 .capab = TCA_CAP_NONE,
232 .owner = THIS_MODULE,
234 .dump = tcf_pedit_dump,
235 .cleanup = tcf_pedit_cleanup,
236 .lookup = tcf_hash_search,
237 .init = tcf_pedit_init,
238 .walk = tcf_generic_walker
241 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
242 MODULE_DESCRIPTION("Generic Packet Editor actions");
243 MODULE_LICENSE("GPL");
245 static int __init pedit_init_module(void)
247 return tcf_register_action(&act_pedit_ops);
250 static void __exit pedit_cleanup_module(void)
252 tcf_unregister_action(&act_pedit_ops);
255 module_init(pedit_init_module);
256 module_exit(pedit_cleanup_module);