2 * net/sched/ife.c Inter-FE action based on ForCES WG InterFE LFB
5 * draft-ietf-forces-interfelfb-03
8 * "Distributing Linux Traffic Control Classifier-Action
10 * Authors: Jamal Hadi Salim and Damascene M. Joachimpillai
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
17 * copyright Jamal Hadi Salim (2015)
21 #include <linux/types.h>
22 #include <linux/kernel.h>
23 #include <linux/string.h>
24 #include <linux/errno.h>
25 #include <linux/skbuff.h>
26 #include <linux/rtnetlink.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <net/net_namespace.h>
30 #include <net/netlink.h>
31 #include <net/pkt_sched.h>
32 #include <uapi/linux/tc_act/tc_ife.h>
33 #include <net/tc_act/tc_ife.h>
34 #include <linux/etherdevice.h>
37 #define IFE_TAB_MASK 15
39 static unsigned int ife_net_id;
40 static int max_metacnt = IFE_META_MAX + 1;
41 static struct tc_action_ops act_ife_ops;
43 static const struct nla_policy ife_policy[TCA_IFE_MAX + 1] = {
44 [TCA_IFE_PARMS] = { .len = sizeof(struct tc_ife)},
45 [TCA_IFE_DMAC] = { .len = ETH_ALEN},
46 [TCA_IFE_SMAC] = { .len = ETH_ALEN},
47 [TCA_IFE_TYPE] = { .type = NLA_U16},
50 int ife_encode_meta_u16(u16 metaval, void *skbdata, struct tcf_meta_info *mi)
55 edata = *(u16 *)mi->metaval;
59 if (!edata) /* will not encode */
63 return ife_tlv_meta_encode(skbdata, mi->metaid, 2, &edata);
65 EXPORT_SYMBOL_GPL(ife_encode_meta_u16);
67 int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi)
70 return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval);
72 return nla_put(skb, mi->metaid, 0, NULL);
74 EXPORT_SYMBOL_GPL(ife_get_meta_u32);
76 int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi)
78 if (metaval || mi->metaval)
79 return 8; /* T+L+V == 2+2+4 */
83 EXPORT_SYMBOL_GPL(ife_check_meta_u32);
85 int ife_check_meta_u16(u16 metaval, struct tcf_meta_info *mi)
87 if (metaval || mi->metaval)
88 return 8; /* T+L+(V) == 2+2+(2+2bytepad) */
92 EXPORT_SYMBOL_GPL(ife_check_meta_u16);
94 int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi)
99 edata = *(u32 *)mi->metaval;
103 if (!edata) /* will not encode */
106 edata = htonl(edata);
107 return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata);
109 EXPORT_SYMBOL_GPL(ife_encode_meta_u32);
111 int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi)
114 return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval);
116 return nla_put(skb, mi->metaid, 0, NULL);
118 EXPORT_SYMBOL_GPL(ife_get_meta_u16);
120 int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp)
122 mi->metaval = kmemdup(metaval, sizeof(u32), gfp);
128 EXPORT_SYMBOL_GPL(ife_alloc_meta_u32);
130 int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp)
132 mi->metaval = kmemdup(metaval, sizeof(u16), gfp);
138 EXPORT_SYMBOL_GPL(ife_alloc_meta_u16);
140 void ife_release_meta_gen(struct tcf_meta_info *mi)
144 EXPORT_SYMBOL_GPL(ife_release_meta_gen);
146 int ife_validate_meta_u32(void *val, int len)
148 if (len == sizeof(u32))
153 EXPORT_SYMBOL_GPL(ife_validate_meta_u32);
155 int ife_validate_meta_u16(void *val, int len)
157 /* length will not include padding */
158 if (len == sizeof(u16))
163 EXPORT_SYMBOL_GPL(ife_validate_meta_u16);
165 static LIST_HEAD(ifeoplist);
166 static DEFINE_RWLOCK(ife_mod_lock);
168 static struct tcf_meta_ops *find_ife_oplist(u16 metaid)
170 struct tcf_meta_ops *o;
172 read_lock(&ife_mod_lock);
173 list_for_each_entry(o, &ifeoplist, list) {
174 if (o->metaid == metaid) {
175 if (!try_module_get(o->owner))
177 read_unlock(&ife_mod_lock);
181 read_unlock(&ife_mod_lock);
186 int register_ife_op(struct tcf_meta_ops *mops)
188 struct tcf_meta_ops *m;
190 if (!mops->metaid || !mops->metatype || !mops->name ||
191 !mops->check_presence || !mops->encode || !mops->decode ||
192 !mops->get || !mops->alloc)
195 write_lock(&ife_mod_lock);
197 list_for_each_entry(m, &ifeoplist, list) {
198 if (m->metaid == mops->metaid ||
199 (strcmp(mops->name, m->name) == 0)) {
200 write_unlock(&ife_mod_lock);
206 mops->release = ife_release_meta_gen;
208 list_add_tail(&mops->list, &ifeoplist);
209 write_unlock(&ife_mod_lock);
212 EXPORT_SYMBOL_GPL(unregister_ife_op);
214 int unregister_ife_op(struct tcf_meta_ops *mops)
216 struct tcf_meta_ops *m;
219 write_lock(&ife_mod_lock);
220 list_for_each_entry(m, &ifeoplist, list) {
221 if (m->metaid == mops->metaid) {
222 list_del(&mops->list);
227 write_unlock(&ife_mod_lock);
231 EXPORT_SYMBOL_GPL(register_ife_op);
233 static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len)
236 /* XXX: unfortunately cant use nla_policy at this point
237 * because a length of 0 is valid in the case of
238 * "allow". "use" semantics do enforce for proper
239 * length and i couldve use nla_policy but it makes it hard
240 * to use it just for that..
243 return ops->validate(val, len);
245 if (ops->metatype == NLA_U32)
246 ret = ife_validate_meta_u32(val, len);
247 else if (ops->metatype == NLA_U16)
248 ret = ife_validate_meta_u16(val, len);
253 /* called when adding new meta information
254 * under ife->tcf_lock for existing action
256 static int load_metaops_and_vet(struct tcf_ife_info *ife, u32 metaid,
257 void *val, int len, bool exists)
259 struct tcf_meta_ops *ops = find_ife_oplist(metaid);
264 #ifdef CONFIG_MODULES
266 spin_unlock_bh(&ife->tcf_lock);
268 request_module("ifemeta%u", metaid);
271 spin_lock_bh(&ife->tcf_lock);
272 ops = find_ife_oplist(metaid);
279 ret = ife_validate_metatype(ops, val, len);
281 module_put(ops->owner);
287 /* called when adding new meta information
288 * under ife->tcf_lock for existing action
290 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval,
291 int len, bool atomic)
293 struct tcf_meta_info *mi = NULL;
294 struct tcf_meta_ops *ops = find_ife_oplist(metaid);
300 mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL);
302 /*put back what find_ife_oplist took */
303 module_put(ops->owner);
310 ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL);
313 module_put(ops->owner);
318 list_add_tail(&mi->metalist, &ife->metalist);
323 static int use_all_metadata(struct tcf_ife_info *ife)
325 struct tcf_meta_ops *o;
329 read_lock(&ife_mod_lock);
330 list_for_each_entry(o, &ifeoplist, list) {
331 rc = add_metainfo(ife, o->metaid, NULL, 0, true);
335 read_unlock(&ife_mod_lock);
343 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife)
345 struct tcf_meta_info *e;
347 unsigned char *b = skb_tail_pointer(skb);
348 int total_encoded = 0;
350 /*can only happen on decode */
351 if (list_empty(&ife->metalist))
354 nest = nla_nest_start(skb, TCA_IFE_METALST);
358 list_for_each_entry(e, &ife->metalist, metalist) {
359 if (!e->ops->get(skb, e))
366 nla_nest_end(skb, nest);
375 /* under ife->tcf_lock */
376 static void _tcf_ife_cleanup(struct tc_action *a, int bind)
378 struct tcf_ife_info *ife = to_ife(a);
379 struct tcf_meta_info *e, *n;
381 list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
382 module_put(e->ops->owner);
383 list_del(&e->metalist);
394 static void tcf_ife_cleanup(struct tc_action *a, int bind)
396 struct tcf_ife_info *ife = to_ife(a);
398 spin_lock_bh(&ife->tcf_lock);
399 _tcf_ife_cleanup(a, bind);
400 spin_unlock_bh(&ife->tcf_lock);
403 /* under ife->tcf_lock for existing action */
404 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb,
412 for (i = 1; i < max_metacnt; i++) {
414 val = nla_data(tb[i]);
415 len = nla_len(tb[i]);
417 rc = load_metaops_and_vet(ife, i, val, len, exists);
421 rc = add_metainfo(ife, i, val, len, exists);
430 static int tcf_ife_init(struct net *net, struct nlattr *nla,
431 struct nlattr *est, struct tc_action **a,
434 struct tc_action_net *tn = net_generic(net, ife_net_id);
435 struct nlattr *tb[TCA_IFE_MAX + 1];
436 struct nlattr *tb2[IFE_META_MAX + 1];
437 struct tcf_ife_info *ife;
446 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy);
450 if (!tb[TCA_IFE_PARMS])
453 parm = nla_data(tb[TCA_IFE_PARMS]);
455 exists = tcf_hash_check(tn, parm->index, a, bind);
459 if (parm->flags & IFE_ENCODE) {
460 /* Until we get issued the ethertype, we cant have
463 if (!tb[TCA_IFE_TYPE]) {
465 tcf_hash_release(*a, bind);
466 pr_info("You MUST pass etherype for encoding\n");
472 ret = tcf_hash_create(tn, parm->index, est, a, &act_ife_ops,
478 tcf_hash_release(*a, bind);
484 ife->flags = parm->flags;
486 if (parm->flags & IFE_ENCODE) {
487 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]);
488 if (tb[TCA_IFE_DMAC])
489 daddr = nla_data(tb[TCA_IFE_DMAC]);
490 if (tb[TCA_IFE_SMAC])
491 saddr = nla_data(tb[TCA_IFE_SMAC]);
495 spin_lock_bh(&ife->tcf_lock);
496 ife->tcf_action = parm->action;
498 if (parm->flags & IFE_ENCODE) {
500 ether_addr_copy(ife->eth_dst, daddr);
502 eth_zero_addr(ife->eth_dst);
505 ether_addr_copy(ife->eth_src, saddr);
507 eth_zero_addr(ife->eth_src);
509 ife->eth_type = ife_type;
512 if (ret == ACT_P_CREATED)
513 INIT_LIST_HEAD(&ife->metalist);
515 if (tb[TCA_IFE_METALST]) {
516 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST],
521 tcf_hash_release(*a, bind);
522 if (ret == ACT_P_CREATED)
523 _tcf_ife_cleanup(*a, bind);
526 spin_unlock_bh(&ife->tcf_lock);
530 err = populate_metalist(ife, tb2, exists);
532 goto metadata_parse_err;
535 /* if no passed metadata allow list or passed allow-all
536 * then here we process by adding as many supported metadatum
537 * as we can. You better have at least one else we are
540 err = use_all_metadata(ife);
542 if (ret == ACT_P_CREATED)
543 _tcf_ife_cleanup(*a, bind);
546 spin_unlock_bh(&ife->tcf_lock);
552 spin_unlock_bh(&ife->tcf_lock);
554 if (ret == ACT_P_CREATED)
555 tcf_hash_insert(tn, *a);
560 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind,
563 unsigned char *b = skb_tail_pointer(skb);
564 struct tcf_ife_info *ife = to_ife(a);
565 struct tc_ife opt = {
566 .index = ife->tcf_index,
567 .refcnt = ife->tcf_refcnt - ref,
568 .bindcnt = ife->tcf_bindcnt - bind,
569 .action = ife->tcf_action,
574 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt))
575 goto nla_put_failure;
577 tcf_tm_dump(&t, &ife->tcf_tm);
578 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD))
579 goto nla_put_failure;
581 if (!is_zero_ether_addr(ife->eth_dst)) {
582 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, ife->eth_dst))
583 goto nla_put_failure;
586 if (!is_zero_ether_addr(ife->eth_src)) {
587 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, ife->eth_src))
588 goto nla_put_failure;
591 if (nla_put(skb, TCA_IFE_TYPE, 2, &ife->eth_type))
592 goto nla_put_failure;
594 if (dump_metalist(skb, ife)) {
595 /*ignore failure to dump metalist */
596 pr_info("Failed to dump metalist\n");
606 int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife,
607 u16 metaid, u16 mlen, void *mdata)
609 struct tcf_meta_info *e;
611 /* XXX: use hash to speed up */
612 list_for_each_entry(e, &ife->metalist, metalist) {
613 if (metaid == e->metaid) {
615 /* We check for decode presence already */
616 return e->ops->decode(skb, mdata, mlen);
624 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a,
625 struct tcf_result *res)
627 struct tcf_ife_info *ife = to_ife(a);
628 int action = ife->tcf_action;
633 spin_lock(&ife->tcf_lock);
634 bstats_update(&ife->tcf_bstats, skb);
635 tcf_lastuse_update(&ife->tcf_tm);
636 spin_unlock(&ife->tcf_lock);
638 if (skb_at_tc_ingress(skb))
639 skb_push(skb, skb->dev->hard_header_len);
641 tlv_data = ife_decode(skb, &metalen);
642 if (unlikely(!tlv_data)) {
643 spin_lock(&ife->tcf_lock);
644 ife->tcf_qstats.drops++;
645 spin_unlock(&ife->tcf_lock);
649 ifehdr_end = tlv_data + metalen;
650 for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) {
655 curr_data = ife_tlv_meta_decode(tlv_data, &mtype, &dlen, NULL);
657 if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) {
658 /* abuse overlimits to count when we receive metadata
659 * but dont have an ops for it
661 pr_info_ratelimited("Unknown metaid %d dlen %d\n",
663 ife->tcf_qstats.overlimits++;
667 if (WARN_ON(tlv_data != ifehdr_end)) {
668 spin_lock(&ife->tcf_lock);
669 ife->tcf_qstats.drops++;
670 spin_unlock(&ife->tcf_lock);
674 skb->protocol = eth_type_trans(skb, skb->dev);
675 skb_reset_network_header(skb);
680 /*XXX: check if we can do this at install time instead of current
683 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife)
685 struct tcf_meta_info *e, *n;
686 int tot_run_sz = 0, run_sz = 0;
688 list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
689 if (e->ops->check_presence) {
690 run_sz = e->ops->check_presence(skb, e);
691 tot_run_sz += run_sz;
698 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a,
699 struct tcf_result *res)
701 struct tcf_ife_info *ife = to_ife(a);
702 int action = ife->tcf_action;
703 struct ethhdr *oethh; /* outer ether header */
704 struct tcf_meta_info *e;
706 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA
707 where ORIGDATA = original ethernet header ...
709 u16 metalen = ife_get_sz(skb, ife);
710 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN;
711 unsigned int skboff = 0;
712 int new_len = skb->len + hdrm;
713 bool exceed_mtu = false;
717 if (!skb_at_tc_ingress(skb)) {
718 if (new_len > skb->dev->mtu)
722 spin_lock(&ife->tcf_lock);
723 bstats_update(&ife->tcf_bstats, skb);
724 tcf_lastuse_update(&ife->tcf_tm);
726 if (!metalen) { /* no metadata to send */
727 /* abuse overlimits to count when we allow packet
730 ife->tcf_qstats.overlimits++;
731 spin_unlock(&ife->tcf_lock);
734 /* could be stupid policy setup or mtu config
735 * so lets be conservative.. */
736 if ((action == TC_ACT_SHOT) || exceed_mtu) {
737 ife->tcf_qstats.drops++;
738 spin_unlock(&ife->tcf_lock);
742 if (skb_at_tc_ingress(skb))
743 skb_push(skb, skb->dev->hard_header_len);
745 ife_meta = ife_encode(skb, metalen);
747 /* XXX: we dont have a clever way of telling encode to
748 * not repeat some of the computations that are done by
749 * ops->presence_check...
751 list_for_each_entry(e, &ife->metalist, metalist) {
752 if (e->ops->encode) {
753 err = e->ops->encode(skb, (void *)(ife_meta + skboff),
757 /* too corrupt to keep around if overwritten */
758 ife->tcf_qstats.drops++;
759 spin_unlock(&ife->tcf_lock);
764 oethh = (struct ethhdr *)skb->data;
766 if (!is_zero_ether_addr(ife->eth_src))
767 ether_addr_copy(oethh->h_source, ife->eth_src);
768 if (!is_zero_ether_addr(ife->eth_dst))
769 ether_addr_copy(oethh->h_dest, ife->eth_dst);
770 oethh->h_proto = htons(ife->eth_type);
772 if (skb_at_tc_ingress(skb))
773 skb_pull(skb, skb->dev->hard_header_len);
775 spin_unlock(&ife->tcf_lock);
780 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a,
781 struct tcf_result *res)
783 struct tcf_ife_info *ife = to_ife(a);
785 if (ife->flags & IFE_ENCODE)
786 return tcf_ife_encode(skb, a, res);
788 if (!(ife->flags & IFE_ENCODE))
789 return tcf_ife_decode(skb, a, res);
791 pr_info_ratelimited("unknown failure(policy neither de/encode\n");
792 spin_lock(&ife->tcf_lock);
793 bstats_update(&ife->tcf_bstats, skb);
794 tcf_lastuse_update(&ife->tcf_tm);
795 ife->tcf_qstats.drops++;
796 spin_unlock(&ife->tcf_lock);
801 static int tcf_ife_walker(struct net *net, struct sk_buff *skb,
802 struct netlink_callback *cb, int type,
803 const struct tc_action_ops *ops)
805 struct tc_action_net *tn = net_generic(net, ife_net_id);
807 return tcf_generic_walker(tn, skb, cb, type, ops);
810 static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index)
812 struct tc_action_net *tn = net_generic(net, ife_net_id);
814 return tcf_hash_search(tn, a, index);
817 static struct tc_action_ops act_ife_ops = {
820 .owner = THIS_MODULE,
822 .dump = tcf_ife_dump,
823 .cleanup = tcf_ife_cleanup,
824 .init = tcf_ife_init,
825 .walk = tcf_ife_walker,
826 .lookup = tcf_ife_search,
827 .size = sizeof(struct tcf_ife_info),
830 static __net_init int ife_init_net(struct net *net)
832 struct tc_action_net *tn = net_generic(net, ife_net_id);
834 return tc_action_net_init(tn, &act_ife_ops, IFE_TAB_MASK);
837 static void __net_exit ife_exit_net(struct net *net)
839 struct tc_action_net *tn = net_generic(net, ife_net_id);
841 tc_action_net_exit(tn);
844 static struct pernet_operations ife_net_ops = {
845 .init = ife_init_net,
846 .exit = ife_exit_net,
848 .size = sizeof(struct tc_action_net),
851 static int __init ife_init_module(void)
853 return tcf_register_action(&act_ife_ops, &ife_net_ops);
856 static void __exit ife_cleanup_module(void)
858 tcf_unregister_action(&act_ife_ops, &ife_net_ops);
861 module_init(ife_init_module);
862 module_exit(ife_cleanup_module);
864 MODULE_AUTHOR("Jamal Hadi Salim(2015)");
865 MODULE_DESCRIPTION("Inter-FE LFB action");
866 MODULE_LICENSE("GPL");