act_skbedit.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2008, Intel Corporation.
  4 *
  5 * Author: Alexander Duyck <alexander.h.duyck@intel.com>
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/init.h>
 10#include <linux/kernel.h>
 11#include <linux/skbuff.h>
 12#include <linux/rtnetlink.h>
 13#include <net/netlink.h>
 14#include <net/pkt_sched.h>
 15#include <net/ip.h>
 16#include <net/ipv6.h>
 17#include <net/dsfield.h>
 18#include <net/pkt_cls.h>
 19#include <net/tc_wrapper.h>
 20
 21#include <linux/tc_act/tc_skbedit.h>
 22#include <net/tc_act/tc_skbedit.h>
 23
 24static struct tc_action_ops act_skbedit_ops;
 25
 26static u16 tcf_skbedit_hash(struct tcf_skbedit_params *params,
 27			    struct sk_buff *skb)
 28{
 29	u16 queue_mapping = params->queue_mapping;
 30
 31	if (params->flags & SKBEDIT_F_TXQ_SKBHASH) {
 32		u32 hash = skb_get_hash(skb);
 33
 34		queue_mapping += hash % params->mapping_mod;
 35	}
 36
 37	return netdev_cap_txqueue(skb->dev, queue_mapping);
 38}
 39
 40TC_INDIRECT_SCOPE int tcf_skbedit_act(struct sk_buff *skb,
 41				      const struct tc_action *a,
 42				      struct tcf_result *res)
 43{
 44	struct tcf_skbedit *d = to_skbedit(a);
 45	struct tcf_skbedit_params *params;
 46
 47	tcf_lastuse_update(&d->tcf_tm);
 48	bstats_update(this_cpu_ptr(d->common.cpu_bstats), skb);
 49
 50	params = rcu_dereference_bh(d->params);
 51
 52	if (params->flags & SKBEDIT_F_PRIORITY)
 53		skb->priority = params->priority;
 54	if (params->flags & SKBEDIT_F_INHERITDSFIELD) {
 55		int wlen = skb_network_offset(skb);
 56
 57		switch (skb_protocol(skb, true)) {
 58		case htons(ETH_P_IP):
 59			wlen += sizeof(struct iphdr);
 60			if (!pskb_may_pull(skb, wlen))
 61				goto err;
 62			skb->priority = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
 63			break;
 64
 65		case htons(ETH_P_IPV6):
 66			wlen += sizeof(struct ipv6hdr);
 67			if (!pskb_may_pull(skb, wlen))
 68				goto err;
 69			skb->priority = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
 70			break;
 71		}
 72	}
 73	if (params->flags & SKBEDIT_F_QUEUE_MAPPING &&
 74	    skb->dev->real_num_tx_queues > params->queue_mapping) {
 75#ifdef CONFIG_NET_EGRESS
 76		netdev_xmit_skip_txqueue(true);
 77#endif
 78		skb_set_queue_mapping(skb, tcf_skbedit_hash(params, skb));
 79	}
 80	if (params->flags & SKBEDIT_F_MARK) {
 81		skb->mark &= ~params->mask;
 82		skb->mark |= params->mark & params->mask;
 83	}
 84	if (params->flags & SKBEDIT_F_PTYPE)
 85		skb->pkt_type = params->ptype;
 86	return params->action;
 87
 88err:
 89	qstats_drop_inc(this_cpu_ptr(d->common.cpu_qstats));
 90	return TC_ACT_SHOT;
 91}
 92
 93static void tcf_skbedit_stats_update(struct tc_action *a, u64 bytes,
 94				     u64 packets, u64 drops,
 95				     u64 lastuse, bool hw)
 96{
 97	struct tcf_skbedit *d = to_skbedit(a);
 98	struct tcf_t *tm = &d->tcf_tm;
 99
100	tcf_action_update_stats(a, bytes, packets, drops, hw);
101	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
102}
103
104static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
105	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
106	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
107	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
108	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
109	[TCA_SKBEDIT_PTYPE]		= { .len = sizeof(u16) },
110	[TCA_SKBEDIT_MASK]		= { .len = sizeof(u32) },
111	[TCA_SKBEDIT_FLAGS]		= { .len = sizeof(u64) },
112	[TCA_SKBEDIT_QUEUE_MAPPING_MAX]	= { .len = sizeof(u16) },
113};
114
115static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
116			    struct nlattr *est, struct tc_action **a,
117			    struct tcf_proto *tp, u32 act_flags,
118			    struct netlink_ext_ack *extack)
119{
120	struct tc_action_net *tn = net_generic(net, act_skbedit_ops.net_id);
121	bool bind = act_flags & TCA_ACT_FLAGS_BIND;
122	struct tcf_skbedit_params *params_new;
123	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
124	struct tcf_chain *goto_ch = NULL;
125	struct tc_skbedit *parm;
126	struct tcf_skbedit *d;
127	u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
128	u16 *queue_mapping = NULL, *ptype = NULL;
129	u32 mapping_mod = 1;
130	bool exists = false;
131	int ret = 0, err;
132	u32 index;
133
134	if (nla == NULL)
135		return -EINVAL;
136
137	err = nla_parse_nested_deprecated(tb, TCA_SKBEDIT_MAX, nla,
138					  skbedit_policy, NULL);
139	if (err < 0)
140		return err;
141
142	if (tb[TCA_SKBEDIT_PARMS] == NULL)
143		return -EINVAL;
144
145	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
146		flags |= SKBEDIT_F_PRIORITY;
147		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
148	}
149
150	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
151		if (is_tcf_skbedit_ingress(act_flags) &&
152		    !(act_flags & TCA_ACT_FLAGS_SKIP_SW)) {
153			NL_SET_ERR_MSG_MOD(extack, "\"queue_mapping\" option on receive side is hardware only, use skip_sw");
154			return -EOPNOTSUPP;
155		}
156		flags |= SKBEDIT_F_QUEUE_MAPPING;
157		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
158	}
159
160	if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
161		ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
162		if (!skb_pkt_type_ok(*ptype))
163			return -EINVAL;
164		flags |= SKBEDIT_F_PTYPE;
165	}
166
167	if (tb[TCA_SKBEDIT_MARK] != NULL) {
168		flags |= SKBEDIT_F_MARK;
169		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
170	}
171
172	if (tb[TCA_SKBEDIT_MASK] != NULL) {
173		flags |= SKBEDIT_F_MASK;
174		mask = nla_data(tb[TCA_SKBEDIT_MASK]);
175	}
176
177	if (tb[TCA_SKBEDIT_FLAGS] != NULL) {
178		u64 *pure_flags = nla_data(tb[TCA_SKBEDIT_FLAGS]);
179
180		if (*pure_flags & SKBEDIT_F_TXQ_SKBHASH) {
181			u16 *queue_mapping_max;
182
183			if (!tb[TCA_SKBEDIT_QUEUE_MAPPING] ||
184			    !tb[TCA_SKBEDIT_QUEUE_MAPPING_MAX]) {
185				NL_SET_ERR_MSG_MOD(extack, "Missing required range of queue_mapping.");
186				return -EINVAL;
187			}
188
189			queue_mapping_max =
190				nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING_MAX]);
191			if (*queue_mapping_max < *queue_mapping) {
192				NL_SET_ERR_MSG_MOD(extack, "The range of queue_mapping is invalid, max < min.");
193				return -EINVAL;
194			}
195
196			mapping_mod = *queue_mapping_max - *queue_mapping + 1;
197			if (mapping_mod > U16_MAX) {
198				NL_SET_ERR_MSG_MOD(extack, "The range of queue_mapping is invalid.");
199				return -EINVAL;
200			}
201			flags |= SKBEDIT_F_TXQ_SKBHASH;
202		}
203		if (*pure_flags & SKBEDIT_F_INHERITDSFIELD)
204			flags |= SKBEDIT_F_INHERITDSFIELD;
205	}
206
207	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
208	index = parm->index;
209	err = tcf_idr_check_alloc(tn, &index, a, bind);
210	if (err < 0)
211		return err;
212	exists = err;
213	if (exists && bind)
214		return ACT_P_BOUND;
215
216	if (!flags) {
217		if (exists)
218			tcf_idr_release(*a, bind);
219		else
220			tcf_idr_cleanup(tn, index);
221		return -EINVAL;
222	}
223
224	if (!exists) {
225		ret = tcf_idr_create(tn, index, est, a,
226				     &act_skbedit_ops, bind, true, act_flags);
227		if (ret) {
228			tcf_idr_cleanup(tn, index);
229			return ret;
230		}
231
232		d = to_skbedit(*a);
233		ret = ACT_P_CREATED;
234	} else {
235		d = to_skbedit(*a);
236		if (!(act_flags & TCA_ACT_FLAGS_REPLACE)) {
237			tcf_idr_release(*a, bind);
238			return -EEXIST;
239		}
240	}
241	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
242	if (err < 0)
243		goto release_idr;
244
245	params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
246	if (unlikely(!params_new)) {
247		err = -ENOMEM;
248		goto put_chain;
249	}
250
251	params_new->flags = flags;
252	if (flags & SKBEDIT_F_PRIORITY)
253		params_new->priority = *priority;
254	if (flags & SKBEDIT_F_QUEUE_MAPPING) {
255		params_new->queue_mapping = *queue_mapping;
256		params_new->mapping_mod = mapping_mod;
257	}
258	if (flags & SKBEDIT_F_MARK)
259		params_new->mark = *mark;
260	if (flags & SKBEDIT_F_PTYPE)
261		params_new->ptype = *ptype;
262	/* default behaviour is to use all the bits */
263	params_new->mask = 0xffffffff;
264	if (flags & SKBEDIT_F_MASK)
265		params_new->mask = *mask;
266
267	params_new->action = parm->action;
268	spin_lock_bh(&d->tcf_lock);
269	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
270	params_new = rcu_replace_pointer(d->params, params_new,
271					 lockdep_is_held(&d->tcf_lock));
272	spin_unlock_bh(&d->tcf_lock);
273	if (params_new)
274		kfree_rcu(params_new, rcu);
275	if (goto_ch)
276		tcf_chain_put_by_act(goto_ch);
277
278	return ret;
279put_chain:
280	if (goto_ch)
281		tcf_chain_put_by_act(goto_ch);
282release_idr:
283	tcf_idr_release(*a, bind);
284	return err;
285}
286
287static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
288			    int bind, int ref)
289{
290	const struct tcf_skbedit *d = to_skbedit(a);
291	unsigned char *b = skb_tail_pointer(skb);
292	const struct tcf_skbedit_params *params;
293	struct tc_skbedit opt = {
294		.index   = d->tcf_index,
295		.refcnt  = refcount_read(&d->tcf_refcnt) - ref,
296		.bindcnt = atomic_read(&d->tcf_bindcnt) - bind,
297	};
298	u64 pure_flags = 0;
299	struct tcf_t t;
300
301	rcu_read_lock();
302	params = rcu_dereference(d->params);
303	opt.action = params->action;
304
305	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
306		goto nla_put_failure;
307	if ((params->flags & SKBEDIT_F_PRIORITY) &&
308	    nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, params->priority))
309		goto nla_put_failure;
310	if ((params->flags & SKBEDIT_F_QUEUE_MAPPING) &&
311	    nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, params->queue_mapping))
312		goto nla_put_failure;
313	if ((params->flags & SKBEDIT_F_MARK) &&
314	    nla_put_u32(skb, TCA_SKBEDIT_MARK, params->mark))
315		goto nla_put_failure;
316	if ((params->flags & SKBEDIT_F_PTYPE) &&
317	    nla_put_u16(skb, TCA_SKBEDIT_PTYPE, params->ptype))
318		goto nla_put_failure;
319	if ((params->flags & SKBEDIT_F_MASK) &&
320	    nla_put_u32(skb, TCA_SKBEDIT_MASK, params->mask))
321		goto nla_put_failure;
322	if (params->flags & SKBEDIT_F_INHERITDSFIELD)
323		pure_flags |= SKBEDIT_F_INHERITDSFIELD;
324	if (params->flags & SKBEDIT_F_TXQ_SKBHASH) {
325		if (nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING_MAX,
326				params->queue_mapping + params->mapping_mod - 1))
327			goto nla_put_failure;
328
329		pure_flags |= SKBEDIT_F_TXQ_SKBHASH;
330	}
331	if (pure_flags != 0 &&
332	    nla_put(skb, TCA_SKBEDIT_FLAGS, sizeof(pure_flags), &pure_flags))
333		goto nla_put_failure;
334
335	tcf_tm_dump(&t, &d->tcf_tm);
336	if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
337		goto nla_put_failure;
338	rcu_read_unlock();
339
340	return skb->len;
341
342nla_put_failure:
343	rcu_read_unlock();
344	nlmsg_trim(skb, b);
345	return -1;
346}
347
348static void tcf_skbedit_cleanup(struct tc_action *a)
349{
350	struct tcf_skbedit *d = to_skbedit(a);
351	struct tcf_skbedit_params *params;
352
353	params = rcu_dereference_protected(d->params, 1);
354	if (params)
355		kfree_rcu(params, rcu);
356}
357
358static size_t tcf_skbedit_get_fill_size(const struct tc_action *act)
359{
360	return nla_total_size(sizeof(struct tc_skbedit))
361		+ nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_PRIORITY */
362		+ nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING */
363		+ nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING_MAX */
364		+ nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MARK */
365		+ nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_PTYPE */
366		+ nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MASK */
367		+ nla_total_size_64bit(sizeof(u64)); /* TCA_SKBEDIT_FLAGS */
368}
369
370static int tcf_skbedit_offload_act_setup(struct tc_action *act, void *entry_data,
371					 u32 *index_inc, bool bind,
372					 struct netlink_ext_ack *extack)
373{
374	if (bind) {
375		struct flow_action_entry *entry = entry_data;
376
377		if (is_tcf_skbedit_mark(act)) {
378			entry->id = FLOW_ACTION_MARK;
379			entry->mark = tcf_skbedit_mark(act);
380		} else if (is_tcf_skbedit_ptype(act)) {
381			entry->id = FLOW_ACTION_PTYPE;
382			entry->ptype = tcf_skbedit_ptype(act);
383		} else if (is_tcf_skbedit_priority(act)) {
384			entry->id = FLOW_ACTION_PRIORITY;
385			entry->priority = tcf_skbedit_priority(act);
386		} else if (is_tcf_skbedit_tx_queue_mapping(act)) {
387			NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"queue_mapping\" option is used on transmit side");
388			return -EOPNOTSUPP;
389		} else if (is_tcf_skbedit_rx_queue_mapping(act)) {
390			entry->id = FLOW_ACTION_RX_QUEUE_MAPPING;
391			entry->rx_queue = tcf_skbedit_rx_queue_mapping(act);
392		} else if (is_tcf_skbedit_inheritdsfield(act)) {
393			NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"inheritdsfield\" option is used");
394			return -EOPNOTSUPP;
395		} else {
396			NL_SET_ERR_MSG_MOD(extack, "Unsupported skbedit option offload");
397			return -EOPNOTSUPP;
398		}
399		*index_inc = 1;
400	} else {
401		struct flow_offload_action *fl_action = entry_data;
402
403		if (is_tcf_skbedit_mark(act))
404			fl_action->id = FLOW_ACTION_MARK;
405		else if (is_tcf_skbedit_ptype(act))
406			fl_action->id = FLOW_ACTION_PTYPE;
407		else if (is_tcf_skbedit_priority(act))
408			fl_action->id = FLOW_ACTION_PRIORITY;
409		else if (is_tcf_skbedit_rx_queue_mapping(act))
410			fl_action->id = FLOW_ACTION_RX_QUEUE_MAPPING;
411		else
412			return -EOPNOTSUPP;
413	}
414
415	return 0;
416}
417
418static struct tc_action_ops act_skbedit_ops = {
419	.kind		=	"skbedit",
420	.id		=	TCA_ID_SKBEDIT,
421	.owner		=	THIS_MODULE,
422	.act		=	tcf_skbedit_act,
423	.stats_update	=	tcf_skbedit_stats_update,
424	.dump		=	tcf_skbedit_dump,
425	.init		=	tcf_skbedit_init,
426	.cleanup	=	tcf_skbedit_cleanup,
427	.get_fill_size	=	tcf_skbedit_get_fill_size,
428	.offload_act_setup =	tcf_skbedit_offload_act_setup,
429	.size		=	sizeof(struct tcf_skbedit),
430};
431MODULE_ALIAS_NET_ACT("skbedit");
432
433static __net_init int skbedit_init_net(struct net *net)
434{
435	struct tc_action_net *tn = net_generic(net, act_skbedit_ops.net_id);
436
437	return tc_action_net_init(net, tn, &act_skbedit_ops);
438}
439
440static void __net_exit skbedit_exit_net(struct list_head *net_list)
441{
442	tc_action_net_exit(net_list, act_skbedit_ops.net_id);
443}
444
445static struct pernet_operations skbedit_net_ops = {
446	.init = skbedit_init_net,
447	.exit_batch = skbedit_exit_net,
448	.id   = &act_skbedit_ops.net_id,
449	.size = sizeof(struct tc_action_net),
450};
451
452MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
453MODULE_DESCRIPTION("SKB Editing");
454MODULE_LICENSE("GPL");
455
456static int __init skbedit_init_module(void)
457{
458	return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
459}
460
461static void __exit skbedit_cleanup_module(void)
462{
463	tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
464}
465
466module_init(skbedit_init_module);
467module_exit(skbedit_cleanup_module);