1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * net/sched/act_pedit.c Generic packet editor
5 * Authors: Jamal Hadi Salim (2002-4)
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/string.h>
11 #include <linux/errno.h>
12 #include <linux/skbuff.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <net/netlink.h>
18 #include <net/pkt_sched.h>
19 #include <linux/tc_act/tc_pedit.h>
20 #include <net/tc_act/tc_pedit.h>
21 #include <uapi/linux/tc_act/tc_pedit.h>
22 #include <net/pkt_cls.h>
24 static unsigned int pedit_net_id;
25 static struct tc_action_ops act_pedit_ops;
27 static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
28 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
29 [TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED },
32 static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
33 [TCA_PEDIT_KEY_EX_HTYPE] = { .type = NLA_U16 },
34 [TCA_PEDIT_KEY_EX_CMD] = { .type = NLA_U16 },
37 static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla,
40 struct tcf_pedit_key_ex *keys_ex;
41 struct tcf_pedit_key_ex *k;
42 const struct nlattr *ka;
49 keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
51 return ERR_PTR(-ENOMEM);
55 nla_for_each_nested(ka, nla, rem) {
56 struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
64 if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
69 err = nla_parse_nested_deprecated(tb, TCA_PEDIT_KEY_EX_MAX,
70 ka, pedit_key_ex_policy,
75 if (!tb[TCA_PEDIT_KEY_EX_HTYPE] ||
76 !tb[TCA_PEDIT_KEY_EX_CMD]) {
81 k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
82 k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
84 if (k->htype > TCA_PEDIT_HDR_TYPE_MAX ||
85 k->cmd > TCA_PEDIT_CMD_MAX) {
105 static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
106 struct tcf_pedit_key_ex *keys_ex, int n)
108 struct nlattr *keys_start = nla_nest_start_noflag(skb,
114 struct nlattr *key_start;
116 key_start = nla_nest_start_noflag(skb, TCA_PEDIT_KEY_EX);
120 if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) ||
121 nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
124 nla_nest_end(skb, key_start);
129 nla_nest_end(skb, keys_start);
133 nla_nest_cancel(skb, keys_start);
137 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
138 struct nlattr *est, struct tc_action **a,
139 struct tcf_proto *tp, u32 flags,
140 struct netlink_ext_ack *extack)
142 struct tc_action_net *tn = net_generic(net, pedit_net_id);
143 bool bind = flags & TCA_ACT_FLAGS_BIND;
144 struct nlattr *tb[TCA_PEDIT_MAX + 1];
145 struct tcf_chain *goto_ch = NULL;
146 struct tc_pedit_key *keys = NULL;
147 struct tcf_pedit_key_ex *keys_ex;
148 struct tc_pedit *parm;
149 struct nlattr *pattr;
156 NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
160 err = nla_parse_nested_deprecated(tb, TCA_PEDIT_MAX, nla,
165 pattr = tb[TCA_PEDIT_PARMS];
167 pattr = tb[TCA_PEDIT_PARMS_EX];
169 NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
173 parm = nla_data(pattr);
175 NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
178 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
179 if (nla_len(pattr) < sizeof(*parm) + ksize) {
180 NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
184 keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
186 return PTR_ERR(keys_ex);
189 err = tcf_idr_check_alloc(tn, &index, a, bind);
191 ret = tcf_idr_create(tn, index, est, a,
192 &act_pedit_ops, bind, false, flags);
194 tcf_idr_cleanup(tn, index);
198 } else if (err > 0) {
201 if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
210 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
216 spin_lock_bh(&p->tcf_lock);
218 if (ret == ACT_P_CREATED ||
219 (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
220 keys = kmalloc(ksize, GFP_ATOMIC);
222 spin_unlock_bh(&p->tcf_lock);
228 p->tcfp_nkeys = parm->nkeys;
230 memcpy(p->tcfp_keys, parm->keys, ksize);
231 p->tcfp_off_max_hint = 0;
232 for (i = 0; i < p->tcfp_nkeys; ++i) {
233 u32 cur = p->tcfp_keys[i].off;
235 /* The AT option can read a single byte, we can bound the actual
236 * value with uchar max.
238 cur += (0xff & p->tcfp_keys[i].offmask) >> p->tcfp_keys[i].shift;
240 /* Each key touches 4 bytes starting from the computed offset */
241 p->tcfp_off_max_hint = max(p->tcfp_off_max_hint, cur + 4);
244 p->tcfp_flags = parm->flags;
245 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
247 kfree(p->tcfp_keys_ex);
248 p->tcfp_keys_ex = keys_ex;
250 spin_unlock_bh(&p->tcf_lock);
252 tcf_chain_put_by_act(goto_ch);
257 tcf_chain_put_by_act(goto_ch);
259 tcf_idr_release(*a, bind);
266 static void tcf_pedit_cleanup(struct tc_action *a)
268 struct tcf_pedit *p = to_pedit(a);
269 struct tc_pedit_key *keys = p->tcfp_keys;
272 kfree(p->tcfp_keys_ex);
275 static bool offset_valid(struct sk_buff *skb, int offset)
277 if (offset > 0 && offset > skb->len)
280 if (offset < 0 && -offset > skb_headroom(skb))
286 static int pedit_skb_hdr_offset(struct sk_buff *skb,
287 enum pedit_header_type htype, int *hoffset)
292 case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
293 if (skb_mac_header_was_set(skb)) {
294 *hoffset = skb_mac_offset(skb);
298 case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
299 case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
300 case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
301 *hoffset = skb_network_offset(skb);
304 case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
305 case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
306 if (skb_transport_header_was_set(skb)) {
307 *hoffset = skb_transport_offset(skb);
319 static int tcf_pedit_act(struct sk_buff *skb, const struct tc_action *a,
320 struct tcf_result *res)
322 struct tcf_pedit *p = to_pedit(a);
326 spin_lock(&p->tcf_lock);
328 max_offset = (skb_transport_header_was_set(skb) ?
329 skb_transport_offset(skb) :
330 skb_network_offset(skb)) +
331 p->tcfp_off_max_hint;
332 if (skb_ensure_writable(skb, min(skb->len, max_offset)))
335 tcf_lastuse_update(&p->tcf_tm);
337 if (p->tcfp_nkeys > 0) {
338 struct tc_pedit_key *tkey = p->tcfp_keys;
339 struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
340 enum pedit_header_type htype =
341 TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
342 enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
344 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
346 int offset = tkey->off;
352 htype = tkey_ex->htype;
358 rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
360 pr_info("tc action pedit bad header type specified (0x%x)\n",
368 if (!offset_valid(skb, hoffset + tkey->at)) {
369 pr_info("tc action pedit 'at' offset %d out of bounds\n",
373 d = skb_header_pointer(skb, hoffset + tkey->at,
377 offset += (*d & tkey->offmask) >> tkey->shift;
381 pr_info("tc action pedit offset must be on 32 bit boundaries\n");
385 if (!offset_valid(skb, hoffset + offset)) {
386 pr_info("tc action pedit offset %d out of bounds\n",
391 ptr = skb_header_pointer(skb, hoffset + offset,
392 sizeof(hdata), &hdata);
395 /* just do it, baby */
397 case TCA_PEDIT_KEY_EX_CMD_SET:
400 case TCA_PEDIT_KEY_EX_CMD_ADD:
401 val = (*ptr + tkey->val) & ~tkey->mask;
404 pr_info("tc action pedit bad command (%d)\n",
409 *ptr = ((*ptr & tkey->mask) ^ val);
411 skb_store_bits(skb, hoffset + offset, ptr, 4);
416 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
420 p->tcf_qstats.overlimits++;
422 bstats_update(&p->tcf_bstats, skb);
424 spin_unlock(&p->tcf_lock);
425 return p->tcf_action;
428 static void tcf_pedit_stats_update(struct tc_action *a, u64 bytes, u64 packets,
429 u64 drops, u64 lastuse, bool hw)
431 struct tcf_pedit *d = to_pedit(a);
432 struct tcf_t *tm = &d->tcf_tm;
434 tcf_action_update_stats(a, bytes, packets, drops, hw);
435 tm->lastuse = max_t(u64, tm->lastuse, lastuse);
438 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
441 unsigned char *b = skb_tail_pointer(skb);
442 struct tcf_pedit *p = to_pedit(a);
443 struct tc_pedit *opt;
447 s = struct_size(opt, keys, p->tcfp_nkeys);
449 /* netlink spinlocks held above us - must use ATOMIC */
450 opt = kzalloc(s, GFP_ATOMIC);
454 spin_lock_bh(&p->tcf_lock);
455 memcpy(opt->keys, p->tcfp_keys, flex_array_size(opt, keys, p->tcfp_nkeys));
456 opt->index = p->tcf_index;
457 opt->nkeys = p->tcfp_nkeys;
458 opt->flags = p->tcfp_flags;
459 opt->action = p->tcf_action;
460 opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
461 opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
463 if (p->tcfp_keys_ex) {
464 if (tcf_pedit_key_ex_dump(skb,
467 goto nla_put_failure;
469 if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
470 goto nla_put_failure;
472 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
473 goto nla_put_failure;
476 tcf_tm_dump(&t, &p->tcf_tm);
477 if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
478 goto nla_put_failure;
479 spin_unlock_bh(&p->tcf_lock);
485 spin_unlock_bh(&p->tcf_lock);
491 static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
492 struct netlink_callback *cb, int type,
493 const struct tc_action_ops *ops,
494 struct netlink_ext_ack *extack)
496 struct tc_action_net *tn = net_generic(net, pedit_net_id);
498 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
501 static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index)
503 struct tc_action_net *tn = net_generic(net, pedit_net_id);
505 return tcf_idr_search(tn, a, index);
508 static int tcf_pedit_offload_act_setup(struct tc_action *act, void *entry_data,
509 u32 *index_inc, bool bind,
510 struct netlink_ext_ack *extack)
513 struct flow_action_entry *entry = entry_data;
516 for (k = 0; k < tcf_pedit_nkeys(act); k++) {
517 switch (tcf_pedit_cmd(act, k)) {
518 case TCA_PEDIT_KEY_EX_CMD_SET:
519 entry->id = FLOW_ACTION_MANGLE;
521 case TCA_PEDIT_KEY_EX_CMD_ADD:
522 entry->id = FLOW_ACTION_ADD;
525 NL_SET_ERR_MSG_MOD(extack, "Unsupported pedit command offload");
528 entry->mangle.htype = tcf_pedit_htype(act, k);
529 entry->mangle.mask = tcf_pedit_mask(act, k);
530 entry->mangle.val = tcf_pedit_val(act, k);
531 entry->mangle.offset = tcf_pedit_offset(act, k);
532 entry->hw_stats = tc_act_hw_stats(act->hw_stats);
543 static struct tc_action_ops act_pedit_ops = {
546 .owner = THIS_MODULE,
547 .act = tcf_pedit_act,
548 .stats_update = tcf_pedit_stats_update,
549 .dump = tcf_pedit_dump,
550 .cleanup = tcf_pedit_cleanup,
551 .init = tcf_pedit_init,
552 .walk = tcf_pedit_walker,
553 .lookup = tcf_pedit_search,
554 .offload_act_setup = tcf_pedit_offload_act_setup,
555 .size = sizeof(struct tcf_pedit),
558 static __net_init int pedit_init_net(struct net *net)
560 struct tc_action_net *tn = net_generic(net, pedit_net_id);
562 return tc_action_net_init(net, tn, &act_pedit_ops);
565 static void __net_exit pedit_exit_net(struct list_head *net_list)
567 tc_action_net_exit(net_list, pedit_net_id);
570 static struct pernet_operations pedit_net_ops = {
571 .init = pedit_init_net,
572 .exit_batch = pedit_exit_net,
574 .size = sizeof(struct tc_action_net),
577 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
578 MODULE_DESCRIPTION("Generic Packet Editor actions");
579 MODULE_LICENSE("GPL");
581 static int __init pedit_init_module(void)
583 return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
586 static void __exit pedit_cleanup_module(void)
588 tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
591 module_init(pedit_init_module);
592 module_exit(pedit_cleanup_module);