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>
26 #include <net/pkt_cls.h>
28 static unsigned int pedit_net_id;
29 static struct tc_action_ops act_pedit_ops;
31 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
32 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
33 [TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED },
36 static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
37 [TCA_PEDIT_KEY_EX_HTYPE] = { .type = NLA_U16 },
38 [TCA_PEDIT_KEY_EX_CMD] = { .type = NLA_U16 },
41 static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla,
44 struct tcf_pedit_key_ex *keys_ex;
45 struct tcf_pedit_key_ex *k;
46 const struct nlattr *ka;
53 keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
55 return ERR_PTR(-ENOMEM);
59 nla_for_each_nested(ka, nla, rem) {
60 struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
68 if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
73 err = nla_parse_nested_deprecated(tb, TCA_PEDIT_KEY_EX_MAX,
74 ka, pedit_key_ex_policy,
79 if (!tb[TCA_PEDIT_KEY_EX_HTYPE] ||
80 !tb[TCA_PEDIT_KEY_EX_CMD]) {
85 k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
86 k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
88 if (k->htype > TCA_PEDIT_HDR_TYPE_MAX ||
89 k->cmd > TCA_PEDIT_CMD_MAX) {
109 static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
110 struct tcf_pedit_key_ex *keys_ex, int n)
112 struct nlattr *keys_start = nla_nest_start_noflag(skb,
118 struct nlattr *key_start;
120 key_start = nla_nest_start_noflag(skb, TCA_PEDIT_KEY_EX);
124 if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) ||
125 nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
128 nla_nest_end(skb, key_start);
133 nla_nest_end(skb, keys_start);
137 nla_nest_cancel(skb, keys_start);
141 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
142 struct nlattr *est, struct tc_action **a,
143 int ovr, int bind, bool rtnl_held,
144 struct tcf_proto *tp, struct netlink_ext_ack *extack)
146 struct tc_action_net *tn = net_generic(net, pedit_net_id);
147 struct nlattr *tb[TCA_PEDIT_MAX + 1];
148 struct tcf_chain *goto_ch = NULL;
149 struct tc_pedit_key *keys = NULL;
150 struct tcf_pedit_key_ex *keys_ex;
151 struct tc_pedit *parm;
152 struct nlattr *pattr;
158 NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
162 err = nla_parse_nested_deprecated(tb, TCA_PEDIT_MAX, nla,
167 pattr = tb[TCA_PEDIT_PARMS];
169 pattr = tb[TCA_PEDIT_PARMS_EX];
171 NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
175 parm = nla_data(pattr);
176 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
177 if (nla_len(pattr) < sizeof(*parm) + ksize) {
178 NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
182 keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
184 return PTR_ERR(keys_ex);
186 err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
189 tcf_idr_cleanup(tn, parm->index);
190 NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
194 ret = tcf_idr_create(tn, parm->index, est, a,
195 &act_pedit_ops, bind, false);
197 tcf_idr_cleanup(tn, parm->index);
201 } else if (err > 0) {
213 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
219 spin_lock_bh(&p->tcf_lock);
221 if (ret == ACT_P_CREATED ||
222 (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
223 keys = kmalloc(ksize, GFP_ATOMIC);
225 spin_unlock_bh(&p->tcf_lock);
231 p->tcfp_nkeys = parm->nkeys;
233 memcpy(p->tcfp_keys, parm->keys, ksize);
235 p->tcfp_flags = parm->flags;
236 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
238 kfree(p->tcfp_keys_ex);
239 p->tcfp_keys_ex = keys_ex;
241 spin_unlock_bh(&p->tcf_lock);
243 tcf_chain_put_by_act(goto_ch);
244 if (ret == ACT_P_CREATED)
245 tcf_idr_insert(tn, *a);
250 tcf_chain_put_by_act(goto_ch);
252 tcf_idr_release(*a, bind);
259 static void tcf_pedit_cleanup(struct tc_action *a)
261 struct tcf_pedit *p = to_pedit(a);
262 struct tc_pedit_key *keys = p->tcfp_keys;
265 kfree(p->tcfp_keys_ex);
268 static bool offset_valid(struct sk_buff *skb, int offset)
270 if (offset > 0 && offset > skb->len)
273 if (offset < 0 && -offset > skb_headroom(skb))
279 static int pedit_skb_hdr_offset(struct sk_buff *skb,
280 enum pedit_header_type htype, int *hoffset)
285 case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
286 if (skb_mac_header_was_set(skb)) {
287 *hoffset = skb_mac_offset(skb);
291 case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
292 case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
293 case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
294 *hoffset = skb_network_offset(skb);
297 case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
298 case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
299 if (skb_transport_header_was_set(skb)) {
300 *hoffset = skb_transport_offset(skb);
312 static int tcf_pedit_act(struct sk_buff *skb, const struct tc_action *a,
313 struct tcf_result *res)
315 struct tcf_pedit *p = to_pedit(a);
318 if (skb_unclone(skb, GFP_ATOMIC))
319 return p->tcf_action;
321 spin_lock(&p->tcf_lock);
323 tcf_lastuse_update(&p->tcf_tm);
325 if (p->tcfp_nkeys > 0) {
326 struct tc_pedit_key *tkey = p->tcfp_keys;
327 struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
328 enum pedit_header_type htype =
329 TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
330 enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
332 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
334 int offset = tkey->off;
340 htype = tkey_ex->htype;
346 rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
348 pr_info("tc action pedit bad header type specified (0x%x)\n",
356 if (!offset_valid(skb, hoffset + tkey->at)) {
357 pr_info("tc action pedit 'at' offset %d out of bounds\n",
361 d = skb_header_pointer(skb, hoffset + tkey->at,
365 offset += (*d & tkey->offmask) >> tkey->shift;
369 pr_info("tc action pedit offset must be on 32 bit boundaries\n");
373 if (!offset_valid(skb, hoffset + offset)) {
374 pr_info("tc action pedit offset %d out of bounds\n",
379 ptr = skb_header_pointer(skb, hoffset + offset,
380 sizeof(hdata), &hdata);
383 /* just do it, baby */
385 case TCA_PEDIT_KEY_EX_CMD_SET:
388 case TCA_PEDIT_KEY_EX_CMD_ADD:
389 val = (*ptr + tkey->val) & ~tkey->mask;
392 pr_info("tc action pedit bad command (%d)\n",
397 *ptr = ((*ptr & tkey->mask) ^ val);
399 skb_store_bits(skb, hoffset + offset, ptr, 4);
404 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
408 p->tcf_qstats.overlimits++;
410 bstats_update(&p->tcf_bstats, skb);
411 spin_unlock(&p->tcf_lock);
412 return p->tcf_action;
415 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
418 unsigned char *b = skb_tail_pointer(skb);
419 struct tcf_pedit *p = to_pedit(a);
420 struct tc_pedit *opt;
424 s = struct_size(opt, keys, p->tcfp_nkeys);
426 /* netlink spinlocks held above us - must use ATOMIC */
427 opt = kzalloc(s, GFP_ATOMIC);
431 spin_lock_bh(&p->tcf_lock);
432 memcpy(opt->keys, p->tcfp_keys,
433 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
434 opt->index = p->tcf_index;
435 opt->nkeys = p->tcfp_nkeys;
436 opt->flags = p->tcfp_flags;
437 opt->action = p->tcf_action;
438 opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
439 opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
441 if (p->tcfp_keys_ex) {
442 if (tcf_pedit_key_ex_dump(skb,
445 goto nla_put_failure;
447 if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
448 goto nla_put_failure;
450 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
451 goto nla_put_failure;
454 tcf_tm_dump(&t, &p->tcf_tm);
455 if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
456 goto nla_put_failure;
457 spin_unlock_bh(&p->tcf_lock);
463 spin_unlock_bh(&p->tcf_lock);
469 static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
470 struct netlink_callback *cb, int type,
471 const struct tc_action_ops *ops,
472 struct netlink_ext_ack *extack)
474 struct tc_action_net *tn = net_generic(net, pedit_net_id);
476 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
479 static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index)
481 struct tc_action_net *tn = net_generic(net, pedit_net_id);
483 return tcf_idr_search(tn, a, index);
486 static struct tc_action_ops act_pedit_ops = {
489 .owner = THIS_MODULE,
490 .act = tcf_pedit_act,
491 .dump = tcf_pedit_dump,
492 .cleanup = tcf_pedit_cleanup,
493 .init = tcf_pedit_init,
494 .walk = tcf_pedit_walker,
495 .lookup = tcf_pedit_search,
496 .size = sizeof(struct tcf_pedit),
499 static __net_init int pedit_init_net(struct net *net)
501 struct tc_action_net *tn = net_generic(net, pedit_net_id);
503 return tc_action_net_init(tn, &act_pedit_ops);
506 static void __net_exit pedit_exit_net(struct list_head *net_list)
508 tc_action_net_exit(net_list, pedit_net_id);
511 static struct pernet_operations pedit_net_ops = {
512 .init = pedit_init_net,
513 .exit_batch = pedit_exit_net,
515 .size = sizeof(struct tc_action_net),
518 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
519 MODULE_DESCRIPTION("Generic Packet Editor actions");
520 MODULE_LICENSE("GPL");
522 static int __init pedit_init_module(void)
524 return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
527 static void __exit pedit_cleanup_module(void)
529 tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
532 module_init(pedit_init_module);
533 module_exit(pedit_cleanup_module);