1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2 /* Copyright (C) 2019 Netronome Systems, Inc. */ 3 4 #include <linux/if_arp.h> 5 #include <linux/init.h> 6 #include <linux/kernel.h> 7 #include <linux/module.h> 8 #include <linux/mpls.h> 9 #include <linux/rtnetlink.h> 10 #include <linux/skbuff.h> 11 #include <linux/tc_act/tc_mpls.h> 12 #include <net/mpls.h> 13 #include <net/netlink.h> 14 #include <net/pkt_sched.h> 15 #include <net/pkt_cls.h> 16 #include <net/tc_act/tc_mpls.h> 17 #include <net/tc_wrapper.h> 18 19 static struct tc_action_ops act_mpls_ops; 20 21 #define ACT_MPLS_TTL_DEFAULT 255 22 23 static __be32 tcf_mpls_get_lse(struct mpls_shim_hdr *lse, 24 struct tcf_mpls_params *p, bool set_bos) 25 { 26 u32 new_lse = 0; 27 28 if (lse) 29 new_lse = be32_to_cpu(lse->label_stack_entry); 30 31 if (p->tcfm_label != ACT_MPLS_LABEL_NOT_SET) { 32 new_lse &= ~MPLS_LS_LABEL_MASK; 33 new_lse |= p->tcfm_label << MPLS_LS_LABEL_SHIFT; 34 } 35 if (p->tcfm_ttl) { 36 new_lse &= ~MPLS_LS_TTL_MASK; 37 new_lse |= p->tcfm_ttl << MPLS_LS_TTL_SHIFT; 38 } 39 if (p->tcfm_tc != ACT_MPLS_TC_NOT_SET) { 40 new_lse &= ~MPLS_LS_TC_MASK; 41 new_lse |= p->tcfm_tc << MPLS_LS_TC_SHIFT; 42 } 43 if (p->tcfm_bos != ACT_MPLS_BOS_NOT_SET) { 44 new_lse &= ~MPLS_LS_S_MASK; 45 new_lse |= p->tcfm_bos << MPLS_LS_S_SHIFT; 46 } else if (set_bos) { 47 new_lse |= 1 << MPLS_LS_S_SHIFT; 48 } 49 50 return cpu_to_be32(new_lse); 51 } 52 53 TC_INDIRECT_SCOPE int tcf_mpls_act(struct sk_buff *skb, 54 const struct tc_action *a, 55 struct tcf_result *res) 56 { 57 struct tcf_mpls *m = to_mpls(a); 58 struct tcf_mpls_params *p; 59 __be32 new_lse; 60 int ret, mac_len; 61 62 tcf_lastuse_update(&m->tcf_tm); 63 bstats_update(this_cpu_ptr(m->common.cpu_bstats), skb); 64 65 /* Ensure 'data' points at mac_header prior calling mpls manipulating 66 * functions. 67 */ 68 if (skb_at_tc_ingress(skb)) { 69 skb_push_rcsum(skb, skb->mac_len); 70 mac_len = skb->mac_len; 71 } else { 72 mac_len = skb_network_offset(skb); 73 } 74 75 ret = READ_ONCE(m->tcf_action); 76 77 p = rcu_dereference_bh(m->mpls_p); 78 79 switch (p->tcfm_action) { 80 case TCA_MPLS_ACT_POP: 81 if (skb_mpls_pop(skb, p->tcfm_proto, mac_len, 82 skb->dev && skb->dev->type == ARPHRD_ETHER)) 83 goto drop; 84 break; 85 case TCA_MPLS_ACT_PUSH: 86 new_lse = tcf_mpls_get_lse(NULL, p, !eth_p_mpls(skb_protocol(skb, true))); 87 if (skb_mpls_push(skb, new_lse, p->tcfm_proto, mac_len, 88 skb->dev && skb->dev->type == ARPHRD_ETHER)) 89 goto drop; 90 break; 91 case TCA_MPLS_ACT_MAC_PUSH: 92 if (skb_vlan_tag_present(skb)) { 93 if (__vlan_insert_inner_tag(skb, skb->vlan_proto, 94 skb_vlan_tag_get(skb), 95 ETH_HLEN) < 0) 96 goto drop; 97 98 skb->protocol = skb->vlan_proto; 99 __vlan_hwaccel_clear_tag(skb); 100 } 101 102 new_lse = tcf_mpls_get_lse(NULL, p, mac_len || 103 !eth_p_mpls(skb->protocol)); 104 105 if (skb_mpls_push(skb, new_lse, p->tcfm_proto, 0, false)) 106 goto drop; 107 break; 108 case TCA_MPLS_ACT_MODIFY: 109 if (!pskb_may_pull(skb, 110 skb_network_offset(skb) + MPLS_HLEN)) 111 goto drop; 112 new_lse = tcf_mpls_get_lse(mpls_hdr(skb), p, false); 113 if (skb_mpls_update_lse(skb, new_lse)) 114 goto drop; 115 break; 116 case TCA_MPLS_ACT_DEC_TTL: 117 if (skb_mpls_dec_ttl(skb)) 118 goto drop; 119 break; 120 } 121 122 if (skb_at_tc_ingress(skb)) 123 skb_pull_rcsum(skb, skb->mac_len); 124 125 return ret; 126 127 drop: 128 qstats_drop_inc(this_cpu_ptr(m->common.cpu_qstats)); 129 return TC_ACT_SHOT; 130 } 131 132 static int valid_label(const struct nlattr *attr, 133 struct netlink_ext_ack *extack) 134 { 135 const u32 *label = nla_data(attr); 136 137 if (nla_len(attr) != sizeof(*label)) { 138 NL_SET_ERR_MSG_MOD(extack, "Invalid MPLS label length"); 139 return -EINVAL; 140 } 141 142 if (*label & ~MPLS_LABEL_MASK || *label == MPLS_LABEL_IMPLNULL) { 143 NL_SET_ERR_MSG_MOD(extack, "MPLS label out of range"); 144 return -EINVAL; 145 } 146 147 return 0; 148 } 149 150 static const struct nla_policy mpls_policy[TCA_MPLS_MAX + 1] = { 151 [TCA_MPLS_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_mpls)), 152 [TCA_MPLS_PROTO] = { .type = NLA_U16 }, 153 [TCA_MPLS_LABEL] = NLA_POLICY_VALIDATE_FN(NLA_BINARY, 154 valid_label), 155 [TCA_MPLS_TC] = NLA_POLICY_RANGE(NLA_U8, 0, 7), 156 [TCA_MPLS_TTL] = NLA_POLICY_MIN(NLA_U8, 1), 157 [TCA_MPLS_BOS] = NLA_POLICY_RANGE(NLA_U8, 0, 1), 158 }; 159 160 static int tcf_mpls_init(struct net *net, struct nlattr *nla, 161 struct nlattr *est, struct tc_action **a, 162 struct tcf_proto *tp, u32 flags, 163 struct netlink_ext_ack *extack) 164 { 165 struct tc_action_net *tn = net_generic(net, act_mpls_ops.net_id); 166 bool bind = flags & TCA_ACT_FLAGS_BIND; 167 struct nlattr *tb[TCA_MPLS_MAX + 1]; 168 struct tcf_chain *goto_ch = NULL; 169 struct tcf_mpls_params *p; 170 struct tc_mpls *parm; 171 bool exists = false; 172 struct tcf_mpls *m; 173 int ret = 0, err; 174 u8 mpls_ttl = 0; 175 u32 index; 176 177 if (!nla) { 178 NL_SET_ERR_MSG_MOD(extack, "Missing netlink attributes"); 179 return -EINVAL; 180 } 181 182 err = nla_parse_nested(tb, TCA_MPLS_MAX, nla, mpls_policy, extack); 183 if (err < 0) 184 return err; 185 186 if (!tb[TCA_MPLS_PARMS]) { 187 NL_SET_ERR_MSG_MOD(extack, "No MPLS params"); 188 return -EINVAL; 189 } 190 parm = nla_data(tb[TCA_MPLS_PARMS]); 191 index = parm->index; 192 193 err = tcf_idr_check_alloc(tn, &index, a, bind); 194 if (err < 0) 195 return err; 196 exists = err; 197 if (exists && bind) 198 return ACT_P_BOUND; 199 200 if (!exists) { 201 ret = tcf_idr_create(tn, index, est, a, &act_mpls_ops, bind, 202 true, flags); 203 if (ret) { 204 tcf_idr_cleanup(tn, index); 205 return ret; 206 } 207 208 ret = ACT_P_CREATED; 209 } else if (!(flags & TCA_ACT_FLAGS_REPLACE)) { 210 tcf_idr_release(*a, bind); 211 return -EEXIST; 212 } 213 214 /* Verify parameters against action type. */ 215 switch (parm->m_action) { 216 case TCA_MPLS_ACT_POP: 217 if (!tb[TCA_MPLS_PROTO]) { 218 NL_SET_ERR_MSG_MOD(extack, "Protocol must be set for MPLS pop"); 219 err = -EINVAL; 220 goto release_idr; 221 } 222 if (!eth_proto_is_802_3(nla_get_be16(tb[TCA_MPLS_PROTO]))) { 223 NL_SET_ERR_MSG_MOD(extack, "Invalid protocol type for MPLS pop"); 224 err = -EINVAL; 225 goto release_idr; 226 } 227 if (tb[TCA_MPLS_LABEL] || tb[TCA_MPLS_TTL] || tb[TCA_MPLS_TC] || 228 tb[TCA_MPLS_BOS]) { 229 NL_SET_ERR_MSG_MOD(extack, "Label, TTL, TC or BOS cannot be used with MPLS pop"); 230 err = -EINVAL; 231 goto release_idr; 232 } 233 break; 234 case TCA_MPLS_ACT_DEC_TTL: 235 if (tb[TCA_MPLS_PROTO] || tb[TCA_MPLS_LABEL] || 236 tb[TCA_MPLS_TTL] || tb[TCA_MPLS_TC] || tb[TCA_MPLS_BOS]) { 237 NL_SET_ERR_MSG_MOD(extack, "Label, TTL, TC, BOS or protocol cannot be used with MPLS dec_ttl"); 238 err = -EINVAL; 239 goto release_idr; 240 } 241 break; 242 case TCA_MPLS_ACT_PUSH: 243 case TCA_MPLS_ACT_MAC_PUSH: 244 if (!tb[TCA_MPLS_LABEL]) { 245 NL_SET_ERR_MSG_MOD(extack, "Label is required for MPLS push"); 246 err = -EINVAL; 247 goto release_idr; 248 } 249 if (tb[TCA_MPLS_PROTO] && 250 !eth_p_mpls(nla_get_be16(tb[TCA_MPLS_PROTO]))) { 251 NL_SET_ERR_MSG_MOD(extack, "Protocol must be an MPLS type for MPLS push"); 252 err = -EPROTONOSUPPORT; 253 goto release_idr; 254 } 255 /* Push needs a TTL - if not specified, set a default value. */ 256 if (!tb[TCA_MPLS_TTL]) { 257 #if IS_ENABLED(CONFIG_MPLS) 258 mpls_ttl = net->mpls.default_ttl ? 259 net->mpls.default_ttl : ACT_MPLS_TTL_DEFAULT; 260 #else 261 mpls_ttl = ACT_MPLS_TTL_DEFAULT; 262 #endif 263 } 264 break; 265 case TCA_MPLS_ACT_MODIFY: 266 if (tb[TCA_MPLS_PROTO]) { 267 NL_SET_ERR_MSG_MOD(extack, "Protocol cannot be used with MPLS modify"); 268 err = -EINVAL; 269 goto release_idr; 270 } 271 break; 272 default: 273 NL_SET_ERR_MSG_MOD(extack, "Unknown MPLS action"); 274 err = -EINVAL; 275 goto release_idr; 276 } 277 278 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 279 if (err < 0) 280 goto release_idr; 281 282 m = to_mpls(*a); 283 284 p = kzalloc(sizeof(*p), GFP_KERNEL); 285 if (!p) { 286 err = -ENOMEM; 287 goto put_chain; 288 } 289 290 p->tcfm_action = parm->m_action; 291 p->tcfm_label = nla_get_u32_default(tb[TCA_MPLS_LABEL], 292 ACT_MPLS_LABEL_NOT_SET); 293 p->tcfm_tc = nla_get_u8_default(tb[TCA_MPLS_TC], ACT_MPLS_TC_NOT_SET); 294 p->tcfm_ttl = nla_get_u8_default(tb[TCA_MPLS_TTL], mpls_ttl); 295 p->tcfm_bos = nla_get_u8_default(tb[TCA_MPLS_BOS], 296 ACT_MPLS_BOS_NOT_SET); 297 p->tcfm_proto = nla_get_be16_default(tb[TCA_MPLS_PROTO], 298 htons(ETH_P_MPLS_UC)); 299 300 spin_lock_bh(&m->tcf_lock); 301 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 302 p = rcu_replace_pointer(m->mpls_p, p, lockdep_is_held(&m->tcf_lock)); 303 spin_unlock_bh(&m->tcf_lock); 304 305 if (goto_ch) 306 tcf_chain_put_by_act(goto_ch); 307 if (p) 308 kfree_rcu(p, rcu); 309 310 return ret; 311 put_chain: 312 if (goto_ch) 313 tcf_chain_put_by_act(goto_ch); 314 release_idr: 315 tcf_idr_release(*a, bind); 316 return err; 317 } 318 319 static void tcf_mpls_cleanup(struct tc_action *a) 320 { 321 struct tcf_mpls *m = to_mpls(a); 322 struct tcf_mpls_params *p; 323 324 p = rcu_dereference_protected(m->mpls_p, 1); 325 if (p) 326 kfree_rcu(p, rcu); 327 } 328 329 static int tcf_mpls_dump(struct sk_buff *skb, struct tc_action *a, 330 int bind, int ref) 331 { 332 unsigned char *b = skb_tail_pointer(skb); 333 struct tcf_mpls *m = to_mpls(a); 334 struct tcf_mpls_params *p; 335 struct tc_mpls opt = { 336 .index = m->tcf_index, 337 .refcnt = refcount_read(&m->tcf_refcnt) - ref, 338 .bindcnt = atomic_read(&m->tcf_bindcnt) - bind, 339 }; 340 struct tcf_t t; 341 342 spin_lock_bh(&m->tcf_lock); 343 opt.action = m->tcf_action; 344 p = rcu_dereference_protected(m->mpls_p, lockdep_is_held(&m->tcf_lock)); 345 opt.m_action = p->tcfm_action; 346 347 if (nla_put(skb, TCA_MPLS_PARMS, sizeof(opt), &opt)) 348 goto nla_put_failure; 349 350 if (p->tcfm_label != ACT_MPLS_LABEL_NOT_SET && 351 nla_put_u32(skb, TCA_MPLS_LABEL, p->tcfm_label)) 352 goto nla_put_failure; 353 354 if (p->tcfm_tc != ACT_MPLS_TC_NOT_SET && 355 nla_put_u8(skb, TCA_MPLS_TC, p->tcfm_tc)) 356 goto nla_put_failure; 357 358 if (p->tcfm_ttl && nla_put_u8(skb, TCA_MPLS_TTL, p->tcfm_ttl)) 359 goto nla_put_failure; 360 361 if (p->tcfm_bos != ACT_MPLS_BOS_NOT_SET && 362 nla_put_u8(skb, TCA_MPLS_BOS, p->tcfm_bos)) 363 goto nla_put_failure; 364 365 if (nla_put_be16(skb, TCA_MPLS_PROTO, p->tcfm_proto)) 366 goto nla_put_failure; 367 368 tcf_tm_dump(&t, &m->tcf_tm); 369 370 if (nla_put_64bit(skb, TCA_MPLS_TM, sizeof(t), &t, TCA_MPLS_PAD)) 371 goto nla_put_failure; 372 373 spin_unlock_bh(&m->tcf_lock); 374 375 return skb->len; 376 377 nla_put_failure: 378 spin_unlock_bh(&m->tcf_lock); 379 nlmsg_trim(skb, b); 380 return -EMSGSIZE; 381 } 382 383 static int tcf_mpls_offload_act_setup(struct tc_action *act, void *entry_data, 384 u32 *index_inc, bool bind, 385 struct netlink_ext_ack *extack) 386 { 387 if (bind) { 388 struct flow_action_entry *entry = entry_data; 389 390 switch (tcf_mpls_action(act)) { 391 case TCA_MPLS_ACT_PUSH: 392 entry->id = FLOW_ACTION_MPLS_PUSH; 393 entry->mpls_push.proto = tcf_mpls_proto(act); 394 entry->mpls_push.label = tcf_mpls_label(act); 395 entry->mpls_push.tc = tcf_mpls_tc(act); 396 entry->mpls_push.bos = tcf_mpls_bos(act); 397 entry->mpls_push.ttl = tcf_mpls_ttl(act); 398 break; 399 case TCA_MPLS_ACT_POP: 400 entry->id = FLOW_ACTION_MPLS_POP; 401 entry->mpls_pop.proto = tcf_mpls_proto(act); 402 break; 403 case TCA_MPLS_ACT_MODIFY: 404 entry->id = FLOW_ACTION_MPLS_MANGLE; 405 entry->mpls_mangle.label = tcf_mpls_label(act); 406 entry->mpls_mangle.tc = tcf_mpls_tc(act); 407 entry->mpls_mangle.bos = tcf_mpls_bos(act); 408 entry->mpls_mangle.ttl = tcf_mpls_ttl(act); 409 break; 410 case TCA_MPLS_ACT_DEC_TTL: 411 NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"dec_ttl\" option is used"); 412 return -EOPNOTSUPP; 413 case TCA_MPLS_ACT_MAC_PUSH: 414 NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"mac_push\" option is used"); 415 return -EOPNOTSUPP; 416 default: 417 NL_SET_ERR_MSG_MOD(extack, "Unsupported MPLS mode offload"); 418 return -EOPNOTSUPP; 419 } 420 *index_inc = 1; 421 } else { 422 struct flow_offload_action *fl_action = entry_data; 423 424 switch (tcf_mpls_action(act)) { 425 case TCA_MPLS_ACT_PUSH: 426 fl_action->id = FLOW_ACTION_MPLS_PUSH; 427 break; 428 case TCA_MPLS_ACT_POP: 429 fl_action->id = FLOW_ACTION_MPLS_POP; 430 break; 431 case TCA_MPLS_ACT_MODIFY: 432 fl_action->id = FLOW_ACTION_MPLS_MANGLE; 433 break; 434 default: 435 return -EOPNOTSUPP; 436 } 437 } 438 439 return 0; 440 } 441 442 static struct tc_action_ops act_mpls_ops = { 443 .kind = "mpls", 444 .id = TCA_ID_MPLS, 445 .owner = THIS_MODULE, 446 .act = tcf_mpls_act, 447 .dump = tcf_mpls_dump, 448 .init = tcf_mpls_init, 449 .cleanup = tcf_mpls_cleanup, 450 .offload_act_setup = tcf_mpls_offload_act_setup, 451 .size = sizeof(struct tcf_mpls), 452 }; 453 MODULE_ALIAS_NET_ACT("mpls"); 454 455 static __net_init int mpls_init_net(struct net *net) 456 { 457 struct tc_action_net *tn = net_generic(net, act_mpls_ops.net_id); 458 459 return tc_action_net_init(net, tn, &act_mpls_ops); 460 } 461 462 static void __net_exit mpls_exit_net(struct list_head *net_list) 463 { 464 tc_action_net_exit(net_list, act_mpls_ops.net_id); 465 } 466 467 static struct pernet_operations mpls_net_ops = { 468 .init = mpls_init_net, 469 .exit_batch = mpls_exit_net, 470 .id = &act_mpls_ops.net_id, 471 .size = sizeof(struct tc_action_net), 472 }; 473 474 static int __init mpls_init_module(void) 475 { 476 return tcf_register_action(&act_mpls_ops, &mpls_net_ops); 477 } 478 479 static void __exit mpls_cleanup_module(void) 480 { 481 tcf_unregister_action(&act_mpls_ops, &mpls_net_ops); 482 } 483 484 module_init(mpls_init_module); 485 module_exit(mpls_cleanup_module); 486 487 MODULE_SOFTDEP("post: mpls_gso"); 488 MODULE_AUTHOR("Netronome Systems <oss-drivers@netronome.com>"); 489 MODULE_LICENSE("GPL"); 490 MODULE_DESCRIPTION("MPLS manipulation actions"); 491