1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2019 Netronome Systems, Inc. */
4 #include <linux/init.h>
5 #include <linux/kernel.h>
6 #include <linux/module.h>
7 #include <linux/mpls.h>
8 #include <linux/rtnetlink.h>
9 #include <linux/skbuff.h>
10 #include <linux/tc_act/tc_mpls.h>
12 #include <net/netlink.h>
13 #include <net/pkt_sched.h>
14 #include <net/pkt_cls.h>
15 #include <net/tc_act/tc_mpls.h>
17 static unsigned int mpls_net_id;
18 static struct tc_action_ops act_mpls_ops;
20 #define ACT_MPLS_TTL_DEFAULT 255
22 static __be32 tcf_mpls_get_lse(struct mpls_shim_hdr *lse,
23 struct tcf_mpls_params *p, bool set_bos)
28 new_lse = be32_to_cpu(lse->label_stack_entry);
30 if (p->tcfm_label != ACT_MPLS_LABEL_NOT_SET) {
31 new_lse &= ~MPLS_LS_LABEL_MASK;
32 new_lse |= p->tcfm_label << MPLS_LS_LABEL_SHIFT;
35 new_lse &= ~MPLS_LS_TTL_MASK;
36 new_lse |= p->tcfm_ttl << MPLS_LS_TTL_SHIFT;
38 if (p->tcfm_tc != ACT_MPLS_TC_NOT_SET) {
39 new_lse &= ~MPLS_LS_TC_MASK;
40 new_lse |= p->tcfm_tc << MPLS_LS_TC_SHIFT;
42 if (p->tcfm_bos != ACT_MPLS_BOS_NOT_SET) {
43 new_lse &= ~MPLS_LS_S_MASK;
44 new_lse |= p->tcfm_bos << MPLS_LS_S_SHIFT;
46 new_lse |= 1 << MPLS_LS_S_SHIFT;
49 return cpu_to_be32(new_lse);
52 static int tcf_mpls_act(struct sk_buff *skb, const struct tc_action *a,
53 struct tcf_result *res)
55 struct tcf_mpls *m = to_mpls(a);
56 struct tcf_mpls_params *p;
60 tcf_lastuse_update(&m->tcf_tm);
61 bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
63 /* Ensure 'data' points at mac_header prior calling mpls manipulating
66 if (skb_at_tc_ingress(skb))
67 skb_push_rcsum(skb, skb->mac_len);
69 ret = READ_ONCE(m->tcf_action);
71 p = rcu_dereference_bh(m->mpls_p);
73 switch (p->tcfm_action) {
74 case TCA_MPLS_ACT_POP:
75 if (skb_mpls_pop(skb, p->tcfm_proto))
78 case TCA_MPLS_ACT_PUSH:
79 new_lse = tcf_mpls_get_lse(NULL, p, !eth_p_mpls(skb->protocol));
80 if (skb_mpls_push(skb, new_lse, p->tcfm_proto))
83 case TCA_MPLS_ACT_MODIFY:
84 new_lse = tcf_mpls_get_lse(mpls_hdr(skb), p, false);
85 if (skb_mpls_update_lse(skb, new_lse))
88 case TCA_MPLS_ACT_DEC_TTL:
89 if (skb_mpls_dec_ttl(skb))
94 if (skb_at_tc_ingress(skb))
95 skb_pull_rcsum(skb, skb->mac_len);
100 qstats_drop_inc(this_cpu_ptr(m->common.cpu_qstats));
104 static int valid_label(const struct nlattr *attr,
105 struct netlink_ext_ack *extack)
107 const u32 *label = nla_data(attr);
109 if (*label & ~MPLS_LABEL_MASK || *label == MPLS_LABEL_IMPLNULL) {
110 NL_SET_ERR_MSG_MOD(extack, "MPLS label out of range");
117 static const struct nla_policy mpls_policy[TCA_MPLS_MAX + 1] = {
118 [TCA_MPLS_UNSPEC] = { .strict_start_type = TCA_MPLS_UNSPEC + 1 },
119 [TCA_MPLS_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_mpls)),
120 [TCA_MPLS_PROTO] = { .type = NLA_U16 },
121 [TCA_MPLS_LABEL] = NLA_POLICY_VALIDATE_FN(NLA_U32, valid_label),
122 [TCA_MPLS_TC] = NLA_POLICY_RANGE(NLA_U8, 0, 7),
123 [TCA_MPLS_TTL] = NLA_POLICY_MIN(NLA_U8, 1),
124 [TCA_MPLS_BOS] = NLA_POLICY_RANGE(NLA_U8, 0, 1),
127 static int tcf_mpls_init(struct net *net, struct nlattr *nla,
128 struct nlattr *est, struct tc_action **a,
129 int ovr, int bind, bool rtnl_held,
130 struct tcf_proto *tp, struct netlink_ext_ack *extack)
132 struct tc_action_net *tn = net_generic(net, mpls_net_id);
133 struct nlattr *tb[TCA_MPLS_MAX + 1];
134 struct tcf_chain *goto_ch = NULL;
135 struct tcf_mpls_params *p;
136 struct tc_mpls *parm;
143 NL_SET_ERR_MSG_MOD(extack, "Missing netlink attributes");
147 err = nla_parse_nested(tb, TCA_MPLS_MAX, nla, mpls_policy, extack);
151 if (!tb[TCA_MPLS_PARMS]) {
152 NL_SET_ERR_MSG_MOD(extack, "No MPLS params");
155 parm = nla_data(tb[TCA_MPLS_PARMS]);
157 /* Verify parameters against action type. */
158 switch (parm->m_action) {
159 case TCA_MPLS_ACT_POP:
160 if (!tb[TCA_MPLS_PROTO]) {
161 NL_SET_ERR_MSG_MOD(extack, "Protocol must be set for MPLS pop");
164 if (!eth_proto_is_802_3(nla_get_be16(tb[TCA_MPLS_PROTO]))) {
165 NL_SET_ERR_MSG_MOD(extack, "Invalid protocol type for MPLS pop");
168 if (tb[TCA_MPLS_LABEL] || tb[TCA_MPLS_TTL] || tb[TCA_MPLS_TC] ||
170 NL_SET_ERR_MSG_MOD(extack, "Label, TTL, TC or BOS cannot be used with MPLS pop");
174 case TCA_MPLS_ACT_DEC_TTL:
175 if (tb[TCA_MPLS_PROTO] || tb[TCA_MPLS_LABEL] ||
176 tb[TCA_MPLS_TTL] || tb[TCA_MPLS_TC] || tb[TCA_MPLS_BOS]) {
177 NL_SET_ERR_MSG_MOD(extack, "Label, TTL, TC, BOS or protocol cannot be used with MPLS dec_ttl");
181 case TCA_MPLS_ACT_PUSH:
182 if (!tb[TCA_MPLS_LABEL]) {
183 NL_SET_ERR_MSG_MOD(extack, "Label is required for MPLS push");
186 if (tb[TCA_MPLS_PROTO] &&
187 !eth_p_mpls(nla_get_be16(tb[TCA_MPLS_PROTO]))) {
188 NL_SET_ERR_MSG_MOD(extack, "Protocol must be an MPLS type for MPLS push");
189 return -EPROTONOSUPPORT;
191 /* Push needs a TTL - if not specified, set a default value. */
192 if (!tb[TCA_MPLS_TTL]) {
193 #if IS_ENABLED(CONFIG_MPLS)
194 mpls_ttl = net->mpls.default_ttl ?
195 net->mpls.default_ttl : ACT_MPLS_TTL_DEFAULT;
197 mpls_ttl = ACT_MPLS_TTL_DEFAULT;
201 case TCA_MPLS_ACT_MODIFY:
202 if (tb[TCA_MPLS_PROTO]) {
203 NL_SET_ERR_MSG_MOD(extack, "Protocol cannot be used with MPLS modify");
208 NL_SET_ERR_MSG_MOD(extack, "Unknown MPLS action");
212 err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
220 ret = tcf_idr_create(tn, parm->index, est, a,
221 &act_mpls_ops, bind, true);
223 tcf_idr_cleanup(tn, parm->index);
229 tcf_idr_release(*a, bind);
233 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
239 p = kzalloc(sizeof(*p), GFP_KERNEL);
245 p->tcfm_action = parm->m_action;
246 p->tcfm_label = tb[TCA_MPLS_LABEL] ? nla_get_u32(tb[TCA_MPLS_LABEL]) :
247 ACT_MPLS_LABEL_NOT_SET;
248 p->tcfm_tc = tb[TCA_MPLS_TC] ? nla_get_u8(tb[TCA_MPLS_TC]) :
250 p->tcfm_ttl = tb[TCA_MPLS_TTL] ? nla_get_u8(tb[TCA_MPLS_TTL]) :
252 p->tcfm_bos = tb[TCA_MPLS_BOS] ? nla_get_u8(tb[TCA_MPLS_BOS]) :
253 ACT_MPLS_BOS_NOT_SET;
254 p->tcfm_proto = tb[TCA_MPLS_PROTO] ? nla_get_be16(tb[TCA_MPLS_PROTO]) :
255 htons(ETH_P_MPLS_UC);
257 spin_lock_bh(&m->tcf_lock);
258 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
259 rcu_swap_protected(m->mpls_p, p, lockdep_is_held(&m->tcf_lock));
260 spin_unlock_bh(&m->tcf_lock);
263 tcf_chain_put_by_act(goto_ch);
267 if (ret == ACT_P_CREATED)
268 tcf_idr_insert(tn, *a);
272 tcf_chain_put_by_act(goto_ch);
274 tcf_idr_release(*a, bind);
278 static void tcf_mpls_cleanup(struct tc_action *a)
280 struct tcf_mpls *m = to_mpls(a);
281 struct tcf_mpls_params *p;
283 p = rcu_dereference_protected(m->mpls_p, 1);
288 static int tcf_mpls_dump(struct sk_buff *skb, struct tc_action *a,
291 unsigned char *b = skb_tail_pointer(skb);
292 struct tcf_mpls *m = to_mpls(a);
293 struct tcf_mpls_params *p;
294 struct tc_mpls opt = {
295 .index = m->tcf_index,
296 .refcnt = refcount_read(&m->tcf_refcnt) - ref,
297 .bindcnt = atomic_read(&m->tcf_bindcnt) - bind,
301 spin_lock_bh(&m->tcf_lock);
302 opt.action = m->tcf_action;
303 p = rcu_dereference_protected(m->mpls_p, lockdep_is_held(&m->tcf_lock));
304 opt.m_action = p->tcfm_action;
306 if (nla_put(skb, TCA_MPLS_PARMS, sizeof(opt), &opt))
307 goto nla_put_failure;
309 if (p->tcfm_label != ACT_MPLS_LABEL_NOT_SET &&
310 nla_put_u32(skb, TCA_MPLS_LABEL, p->tcfm_label))
311 goto nla_put_failure;
313 if (p->tcfm_tc != ACT_MPLS_TC_NOT_SET &&
314 nla_put_u8(skb, TCA_MPLS_TC, p->tcfm_tc))
315 goto nla_put_failure;
317 if (p->tcfm_ttl && nla_put_u8(skb, TCA_MPLS_TTL, p->tcfm_ttl))
318 goto nla_put_failure;
320 if (p->tcfm_bos != ACT_MPLS_BOS_NOT_SET &&
321 nla_put_u8(skb, TCA_MPLS_BOS, p->tcfm_bos))
322 goto nla_put_failure;
324 if (nla_put_be16(skb, TCA_MPLS_PROTO, p->tcfm_proto))
325 goto nla_put_failure;
327 tcf_tm_dump(&t, &m->tcf_tm);
329 if (nla_put_64bit(skb, TCA_MPLS_TM, sizeof(t), &t, TCA_MPLS_PAD))
330 goto nla_put_failure;
332 spin_unlock_bh(&m->tcf_lock);
337 spin_unlock_bh(&m->tcf_lock);
342 static int tcf_mpls_walker(struct net *net, struct sk_buff *skb,
343 struct netlink_callback *cb, int type,
344 const struct tc_action_ops *ops,
345 struct netlink_ext_ack *extack)
347 struct tc_action_net *tn = net_generic(net, mpls_net_id);
349 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
352 static int tcf_mpls_search(struct net *net, struct tc_action **a, u32 index)
354 struct tc_action_net *tn = net_generic(net, mpls_net_id);
356 return tcf_idr_search(tn, a, index);
359 static struct tc_action_ops act_mpls_ops = {
362 .owner = THIS_MODULE,
364 .dump = tcf_mpls_dump,
365 .init = tcf_mpls_init,
366 .cleanup = tcf_mpls_cleanup,
367 .walk = tcf_mpls_walker,
368 .lookup = tcf_mpls_search,
369 .size = sizeof(struct tcf_mpls),
372 static __net_init int mpls_init_net(struct net *net)
374 struct tc_action_net *tn = net_generic(net, mpls_net_id);
376 return tc_action_net_init(tn, &act_mpls_ops);
379 static void __net_exit mpls_exit_net(struct list_head *net_list)
381 tc_action_net_exit(net_list, mpls_net_id);
384 static struct pernet_operations mpls_net_ops = {
385 .init = mpls_init_net,
386 .exit_batch = mpls_exit_net,
388 .size = sizeof(struct tc_action_net),
391 static int __init mpls_init_module(void)
393 return tcf_register_action(&act_mpls_ops, &mpls_net_ops);
396 static void __exit mpls_cleanup_module(void)
398 tcf_unregister_action(&act_mpls_ops, &mpls_net_ops);
401 module_init(mpls_init_module);
402 module_exit(mpls_cleanup_module);
404 MODULE_AUTHOR("Netronome Systems <oss-drivers@netronome.com>");
405 MODULE_LICENSE("GPL");
406 MODULE_DESCRIPTION("MPLS manipulation actions");