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>
25 #include <uapi/linux/tc_act/tc_pedit.h>
27 static unsigned int pedit_net_id;
28 static struct tc_action_ops act_pedit_ops;
30 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
31 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
32 [TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED },
35 static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
36 [TCA_PEDIT_KEY_EX_HTYPE] = { .type = NLA_U16 },
37 [TCA_PEDIT_KEY_EX_CMD] = { .type = NLA_U16 },
40 static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla,
43 struct tcf_pedit_key_ex *keys_ex;
44 struct tcf_pedit_key_ex *k;
45 const struct nlattr *ka;
52 keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
54 return ERR_PTR(-ENOMEM);
58 nla_for_each_nested(ka, nla, rem) {
59 struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
67 if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
72 err = nla_parse_nested(tb, TCA_PEDIT_KEY_EX_MAX, ka,
73 pedit_key_ex_policy, NULL);
77 if (!tb[TCA_PEDIT_KEY_EX_HTYPE] ||
78 !tb[TCA_PEDIT_KEY_EX_CMD]) {
83 k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
84 k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
86 if (k->htype > TCA_PEDIT_HDR_TYPE_MAX ||
87 k->cmd > TCA_PEDIT_CMD_MAX) {
107 static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
108 struct tcf_pedit_key_ex *keys_ex, int n)
110 struct nlattr *keys_start = nla_nest_start(skb, TCA_PEDIT_KEYS_EX);
113 struct nlattr *key_start;
115 key_start = nla_nest_start(skb, TCA_PEDIT_KEY_EX);
117 if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) ||
118 nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd)) {
119 nlmsg_trim(skb, keys_start);
123 nla_nest_end(skb, key_start);
128 nla_nest_end(skb, keys_start);
133 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
134 struct nlattr *est, struct tc_action **a,
135 int ovr, int bind, bool rtnl_held,
136 struct netlink_ext_ack *extack)
138 struct tc_action_net *tn = net_generic(net, pedit_net_id);
139 struct nlattr *tb[TCA_PEDIT_MAX + 1];
140 struct tc_pedit_key *keys = NULL;
141 struct tcf_pedit_key_ex *keys_ex;
142 struct tc_pedit *parm;
143 struct nlattr *pattr;
149 NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
153 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy, NULL);
157 pattr = tb[TCA_PEDIT_PARMS];
159 pattr = tb[TCA_PEDIT_PARMS_EX];
161 NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
165 parm = nla_data(pattr);
166 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
167 if (nla_len(pattr) < sizeof(*parm) + ksize) {
168 NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
172 keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
174 return PTR_ERR(keys_ex);
176 err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
179 tcf_idr_cleanup(tn, parm->index);
180 NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
184 ret = tcf_idr_create(tn, parm->index, est, a,
185 &act_pedit_ops, bind, false);
187 tcf_idr_cleanup(tn, parm->index);
191 } else if (err > 0) {
203 spin_lock_bh(&p->tcf_lock);
205 if (ret == ACT_P_CREATED ||
206 (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
207 keys = kmalloc(ksize, GFP_ATOMIC);
209 spin_unlock_bh(&p->tcf_lock);
215 p->tcfp_nkeys = parm->nkeys;
217 memcpy(p->tcfp_keys, parm->keys, ksize);
219 p->tcfp_flags = parm->flags;
220 p->tcf_action = parm->action;
222 kfree(p->tcfp_keys_ex);
223 p->tcfp_keys_ex = keys_ex;
225 spin_unlock_bh(&p->tcf_lock);
226 if (ret == ACT_P_CREATED)
227 tcf_idr_insert(tn, *a);
231 tcf_idr_release(*a, bind);
238 static void tcf_pedit_cleanup(struct tc_action *a)
240 struct tcf_pedit *p = to_pedit(a);
241 struct tc_pedit_key *keys = p->tcfp_keys;
244 kfree(p->tcfp_keys_ex);
247 static bool offset_valid(struct sk_buff *skb, int offset)
249 if (offset > 0 && offset > skb->len)
252 if (offset < 0 && -offset > skb_headroom(skb))
258 static int pedit_skb_hdr_offset(struct sk_buff *skb,
259 enum pedit_header_type htype, int *hoffset)
264 case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
265 if (skb_mac_header_was_set(skb)) {
266 *hoffset = skb_mac_offset(skb);
270 case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
271 case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
272 case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
273 *hoffset = skb_network_offset(skb);
276 case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
277 case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
278 if (skb_transport_header_was_set(skb)) {
279 *hoffset = skb_transport_offset(skb);
291 static int tcf_pedit_act(struct sk_buff *skb, const struct tc_action *a,
292 struct tcf_result *res)
294 struct tcf_pedit *p = to_pedit(a);
297 if (skb_unclone(skb, GFP_ATOMIC))
298 return p->tcf_action;
300 spin_lock(&p->tcf_lock);
302 tcf_lastuse_update(&p->tcf_tm);
304 if (p->tcfp_nkeys > 0) {
305 struct tc_pedit_key *tkey = p->tcfp_keys;
306 struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
307 enum pedit_header_type htype =
308 TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
309 enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
311 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
313 int offset = tkey->off;
319 htype = tkey_ex->htype;
325 rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
327 pr_info("tc action pedit bad header type specified (0x%x)\n",
335 if (!offset_valid(skb, hoffset + tkey->at)) {
336 pr_info("tc action pedit 'at' offset %d out of bounds\n",
340 d = skb_header_pointer(skb, hoffset + tkey->at,
344 offset += (*d & tkey->offmask) >> tkey->shift;
348 pr_info("tc action pedit offset must be on 32 bit boundaries\n");
352 if (!offset_valid(skb, hoffset + offset)) {
353 pr_info("tc action pedit offset %d out of bounds\n",
358 ptr = skb_header_pointer(skb, hoffset + offset,
359 sizeof(hdata), &hdata);
362 /* just do it, baby */
364 case TCA_PEDIT_KEY_EX_CMD_SET:
367 case TCA_PEDIT_KEY_EX_CMD_ADD:
368 val = (*ptr + tkey->val) & ~tkey->mask;
371 pr_info("tc action pedit bad command (%d)\n",
376 *ptr = ((*ptr & tkey->mask) ^ val);
378 skb_store_bits(skb, hoffset + offset, ptr, 4);
383 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
387 p->tcf_qstats.overlimits++;
389 bstats_update(&p->tcf_bstats, skb);
390 spin_unlock(&p->tcf_lock);
391 return p->tcf_action;
394 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
397 unsigned char *b = skb_tail_pointer(skb);
398 struct tcf_pedit *p = to_pedit(a);
399 struct tc_pedit *opt;
403 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
405 /* netlink spinlocks held above us - must use ATOMIC */
406 opt = kzalloc(s, GFP_ATOMIC);
410 spin_lock_bh(&p->tcf_lock);
411 memcpy(opt->keys, p->tcfp_keys,
412 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
413 opt->index = p->tcf_index;
414 opt->nkeys = p->tcfp_nkeys;
415 opt->flags = p->tcfp_flags;
416 opt->action = p->tcf_action;
417 opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
418 opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
420 if (p->tcfp_keys_ex) {
421 tcf_pedit_key_ex_dump(skb, p->tcfp_keys_ex, p->tcfp_nkeys);
423 if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
424 goto nla_put_failure;
426 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
427 goto nla_put_failure;
430 tcf_tm_dump(&t, &p->tcf_tm);
431 if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
432 goto nla_put_failure;
433 spin_unlock_bh(&p->tcf_lock);
439 spin_unlock_bh(&p->tcf_lock);
445 static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
446 struct netlink_callback *cb, int type,
447 const struct tc_action_ops *ops,
448 struct netlink_ext_ack *extack)
450 struct tc_action_net *tn = net_generic(net, pedit_net_id);
452 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
455 static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index,
456 struct netlink_ext_ack *extack)
458 struct tc_action_net *tn = net_generic(net, pedit_net_id);
460 return tcf_idr_search(tn, a, index);
463 static int tcf_pedit_delete(struct net *net, u32 index)
465 struct tc_action_net *tn = net_generic(net, pedit_net_id);
467 return tcf_idr_delete_index(tn, index);
470 static struct tc_action_ops act_pedit_ops = {
472 .type = TCA_ACT_PEDIT,
473 .owner = THIS_MODULE,
474 .act = tcf_pedit_act,
475 .dump = tcf_pedit_dump,
476 .cleanup = tcf_pedit_cleanup,
477 .init = tcf_pedit_init,
478 .walk = tcf_pedit_walker,
479 .lookup = tcf_pedit_search,
480 .delete = tcf_pedit_delete,
481 .size = sizeof(struct tcf_pedit),
484 static __net_init int pedit_init_net(struct net *net)
486 struct tc_action_net *tn = net_generic(net, pedit_net_id);
488 return tc_action_net_init(tn, &act_pedit_ops);
491 static void __net_exit pedit_exit_net(struct list_head *net_list)
493 tc_action_net_exit(net_list, pedit_net_id);
496 static struct pernet_operations pedit_net_ops = {
497 .init = pedit_init_net,
498 .exit_batch = pedit_exit_net,
500 .size = sizeof(struct tc_action_net),
503 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
504 MODULE_DESCRIPTION("Generic Packet Editor actions");
505 MODULE_LICENSE("GPL");
507 static int __init pedit_init_module(void)
509 return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
512 static void __exit pedit_cleanup_module(void)
514 tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
517 module_init(pedit_init_module);
518 module_exit(pedit_cleanup_module);