net/ipv6/ioam6.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  IPv6 IOAM implementation
   4  *
   5  *  Author:
   6  *  Justin Iurman <[email protected]>
   7  */
   8
   9 #include <linux/errno.h>
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/net.h>
  13 #include <linux/ioam6.h>
  14 #include <linux/ioam6_genl.h>
  15 #include <linux/rhashtable.h>
  16
  17 #include <net/addrconf.h>
  18 #include <net/genetlink.h>
  19 #include <net/ioam6.h>
  20
  21 static void ioam6_ns_release(struct ioam6_namespace *ns)
  22 {
  23         kfree_rcu(ns, rcu);
  24 }
  25
  26 static void ioam6_sc_release(struct ioam6_schema *sc)
  27 {
  28         kfree_rcu(sc, rcu);
  29 }
  30
  31 static void ioam6_free_ns(void *ptr, void *arg)
  32 {
  33         struct ioam6_namespace *ns = (struct ioam6_namespace *)ptr;
  34
  35         if (ns)
  36                 ioam6_ns_release(ns);
  37 }
  38
  39 static void ioam6_free_sc(void *ptr, void *arg)
  40 {
  41         struct ioam6_schema *sc = (struct ioam6_schema *)ptr;
  42
  43         if (sc)
  44                 ioam6_sc_release(sc);
  45 }
  46
  47 static int ioam6_ns_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
  48 {
  49         const struct ioam6_namespace *ns = obj;
  50
  51         return (ns->id != *(__be16 *)arg->key);
  52 }
  53
  54 static int ioam6_sc_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
  55 {
  56         const struct ioam6_schema *sc = obj;
  57
  58         return (sc->id != *(u32 *)arg->key);
  59 }
  60
  61 static const struct rhashtable_params rht_ns_params = {
  62         .key_len                = sizeof(__be16),
  63         .key_offset             = offsetof(struct ioam6_namespace, id),
  64         .head_offset            = offsetof(struct ioam6_namespace, head),
  65         .automatic_shrinking    = true,
  66         .obj_cmpfn              = ioam6_ns_cmpfn,
  67 };
  68
  69 static const struct rhashtable_params rht_sc_params = {
  70         .key_len                = sizeof(u32),
  71         .key_offset             = offsetof(struct ioam6_schema, id),
  72         .head_offset            = offsetof(struct ioam6_schema, head),
  73         .automatic_shrinking    = true,
  74         .obj_cmpfn              = ioam6_sc_cmpfn,
  75 };
  76
  77 static struct genl_family ioam6_genl_family;
  78
  79 static const struct nla_policy ioam6_genl_policy_addns[] = {
  80         [IOAM6_ATTR_NS_ID]      = { .type = NLA_U16 },
  81         [IOAM6_ATTR_NS_DATA]    = { .type = NLA_U32 },
  82         [IOAM6_ATTR_NS_DATA_WIDE] = { .type = NLA_U64 },
  83 };
  84
  85 static const struct nla_policy ioam6_genl_policy_delns[] = {
  86         [IOAM6_ATTR_NS_ID]      = { .type = NLA_U16 },
  87 };
  88
  89 static const struct nla_policy ioam6_genl_policy_addsc[] = {
  90         [IOAM6_ATTR_SC_ID]      = { .type = NLA_U32 },
  91         [IOAM6_ATTR_SC_DATA]    = { .type = NLA_BINARY,
  92                                     .len = IOAM6_MAX_SCHEMA_DATA_LEN },
  93 };
  94
  95 static const struct nla_policy ioam6_genl_policy_delsc[] = {
  96         [IOAM6_ATTR_SC_ID]      = { .type = NLA_U32 },
  97 };
  98
  99 static const struct nla_policy ioam6_genl_policy_ns_sc[] = {
 100         [IOAM6_ATTR_NS_ID]      = { .type = NLA_U16 },
 101         [IOAM6_ATTR_SC_ID]      = { .type = NLA_U32 },
 102         [IOAM6_ATTR_SC_NONE]    = { .type = NLA_FLAG },
 103 };
 104
 105 static int ioam6_genl_addns(struct sk_buff *skb, struct genl_info *info)
 106 {
 107         struct ioam6_pernet_data *nsdata;
 108         struct ioam6_namespace *ns;
 109         u64 data64;
 110         u32 data32;
 111         __be16 id;
 112         int err;
 113
 114         if (!info->attrs[IOAM6_ATTR_NS_ID])
 115                 return -EINVAL;
 116
 117         id = cpu_to_be16(nla_get_u16(info->attrs[IOAM6_ATTR_NS_ID]));
 118         nsdata = ioam6_pernet(genl_info_net(info));
 119
 120         mutex_lock(&nsdata->lock);
 121
 122         ns = rhashtable_lookup_fast(&nsdata->namespaces, &id, rht_ns_params);
 123         if (ns) {
 124                 err = -EEXIST;
 125                 goto out_unlock;
 126         }
 127
 128         ns = kzalloc(sizeof(*ns), GFP_KERNEL);
 129         if (!ns) {
 130                 err = -ENOMEM;
 131                 goto out_unlock;
 132         }
 133
 134         ns->id = id;
 135
 136         if (!info->attrs[IOAM6_ATTR_NS_DATA])
 137                 data32 = IOAM6_U32_UNAVAILABLE;
 138         else
 139                 data32 = nla_get_u32(info->attrs[IOAM6_ATTR_NS_DATA]);
 140
 141         if (!info->attrs[IOAM6_ATTR_NS_DATA_WIDE])
 142                 data64 = IOAM6_U64_UNAVAILABLE;
 143         else
 144                 data64 = nla_get_u64(info->attrs[IOAM6_ATTR_NS_DATA_WIDE]);
 145
 146         ns->data = cpu_to_be32(data32);
 147         ns->data_wide = cpu_to_be64(data64);
 148
 149         err = rhashtable_lookup_insert_fast(&nsdata->namespaces, &ns->head,
 150                                             rht_ns_params);
 151         if (err)
 152                 kfree(ns);
 153
 154 out_unlock:
 155         mutex_unlock(&nsdata->lock);
 156         return err;
 157 }
 158
 159 static int ioam6_genl_delns(struct sk_buff *skb, struct genl_info *info)
 160 {
 161         struct ioam6_pernet_data *nsdata;
 162         struct ioam6_namespace *ns;
 163         struct ioam6_schema *sc;
 164         __be16 id;
 165         int err;
 166
 167         if (!info->attrs[IOAM6_ATTR_NS_ID])
 168                 return -EINVAL;
 169
 170         id = cpu_to_be16(nla_get_u16(info->attrs[IOAM6_ATTR_NS_ID]));
 171         nsdata = ioam6_pernet(genl_info_net(info));
 172
 173         mutex_lock(&nsdata->lock);
 174
 175         ns = rhashtable_lookup_fast(&nsdata->namespaces, &id, rht_ns_params);
 176         if (!ns) {
 177                 err = -ENOENT;
 178                 goto out_unlock;
 179         }
 180
 181         sc = rcu_dereference_protected(ns->schema,
 182                                        lockdep_is_held(&nsdata->lock));
 183
 184         err = rhashtable_remove_fast(&nsdata->namespaces, &ns->head,
 185                                      rht_ns_params);
 186         if (err)
 187                 goto out_unlock;
 188
 189         if (sc)
 190                 rcu_assign_pointer(sc->ns, NULL);
 191
 192         ioam6_ns_release(ns);
 193
 194 out_unlock:
 195         mutex_unlock(&nsdata->lock);
 196         return err;
 197 }
 198
 199 static int __ioam6_genl_dumpns_element(struct ioam6_namespace *ns,
 200                                        u32 portid,
 201                                        u32 seq,
 202                                        u32 flags,
 203                                        struct sk_buff *skb,
 204                                        u8 cmd)
 205 {
 206         struct ioam6_schema *sc;
 207         u64 data64;
 208         u32 data32;
 209         void *hdr;
 210
 211         hdr = genlmsg_put(skb, portid, seq, &ioam6_genl_family, flags, cmd);
 212         if (!hdr)
 213                 return -ENOMEM;
 214
 215         data32 = be32_to_cpu(ns->data);
 216         data64 = be64_to_cpu(ns->data_wide);
 217
 218         if (nla_put_u16(skb, IOAM6_ATTR_NS_ID, be16_to_cpu(ns->id)) ||
 219             (data32 != IOAM6_U32_UNAVAILABLE &&
 220              nla_put_u32(skb, IOAM6_ATTR_NS_DATA, data32)) ||
 221             (data64 != IOAM6_U64_UNAVAILABLE &&
 222              nla_put_u64_64bit(skb, IOAM6_ATTR_NS_DATA_WIDE,
 223                                data64, IOAM6_ATTR_PAD)))
 224                 goto nla_put_failure;
 225
 226         rcu_read_lock();
 227
 228         sc = rcu_dereference(ns->schema);
 229         if (sc && nla_put_u32(skb, IOAM6_ATTR_SC_ID, sc->id)) {
 230                 rcu_read_unlock();
 231                 goto nla_put_failure;
 232         }
 233
 234         rcu_read_unlock();
 235
 236         genlmsg_end(skb, hdr);
 237         return 0;
 238
 239 nla_put_failure:
 240         genlmsg_cancel(skb, hdr);
 241         return -EMSGSIZE;
 242 }
 243
 244 static int ioam6_genl_dumpns_start(struct netlink_callback *cb)
 245 {
 246         struct ioam6_pernet_data *nsdata = ioam6_pernet(sock_net(cb->skb->sk));
 247         struct rhashtable_iter *iter = (struct rhashtable_iter *)cb->args[0];
 248
 249         if (!iter) {
 250                 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
 251                 if (!iter)
 252                         return -ENOMEM;
 253
 254                 cb->args[0] = (long)iter;
 255         }
 256
 257         rhashtable_walk_enter(&nsdata->namespaces, iter);
 258
 259         return 0;
 260 }
 261
 262 static int ioam6_genl_dumpns_done(struct netlink_callback *cb)
 263 {
 264         struct rhashtable_iter *iter = (struct rhashtable_iter *)cb->args[0];
 265
 266         rhashtable_walk_exit(iter);
 267         kfree(iter);
 268
 269         return 0;
 270 }
 271
 272 static int ioam6_genl_dumpns(struct sk_buff *skb, struct netlink_callback *cb)
 273 {
 274         struct rhashtable_iter *iter;
 275         struct ioam6_namespace *ns;
 276         int err;
 277
 278         iter = (struct rhashtable_iter *)cb->args[0];
 279         rhashtable_walk_start(iter);
 280
 281         for (;;) {
 282                 ns = rhashtable_walk_next(iter);
 283
 284                 if (IS_ERR(ns)) {
 285                         if (PTR_ERR(ns) == -EAGAIN)
 286                                 continue;
 287                         err = PTR_ERR(ns);
 288                         goto done;
 289                 } else if (!ns) {
 290                         break;
 291                 }
 292
 293                 err = __ioam6_genl_dumpns_element(ns,
 294                                                   NETLINK_CB(cb->skb).portid,
 295                                                   cb->nlh->nlmsg_seq,
 296                                                   NLM_F_MULTI,
 297                                                   skb,
 298                                                   IOAM6_CMD_DUMP_NAMESPACES);
 299                 if (err)
 300                         goto done;
 301         }
 302
 303         err = skb->len;
 304
 305 done:
 306         rhashtable_walk_stop(iter);
 307         return err;
 308 }
 309
 310 static int ioam6_genl_addsc(struct sk_buff *skb, struct genl_info *info)
 311 {
 312         struct ioam6_pernet_data *nsdata;
 313         int len, len_aligned, err;
 314         struct ioam6_schema *sc;
 315         u32 id;
 316
 317         if (!info->attrs[IOAM6_ATTR_SC_ID] || !info->attrs[IOAM6_ATTR_SC_DATA])
 318                 return -EINVAL;
 319
 320         id = nla_get_u32(info->attrs[IOAM6_ATTR_SC_ID]);
 321         nsdata = ioam6_pernet(genl_info_net(info));
 322
 323         mutex_lock(&nsdata->lock);
 324
 325         sc = rhashtable_lookup_fast(&nsdata->schemas, &id, rht_sc_params);
 326         if (sc) {
 327                 err = -EEXIST;
 328                 goto out_unlock;
 329         }
 330
 331         len = nla_len(info->attrs[IOAM6_ATTR_SC_DATA]);
 332         len_aligned = ALIGN(len, 4);
 333
 334         sc = kzalloc(sizeof(*sc) + len_aligned, GFP_KERNEL);
 335         if (!sc) {
 336                 err = -ENOMEM;
 337                 goto out_unlock;
 338         }
 339
 340         sc->id = id;
 341         sc->len = len_aligned;
 342         sc->hdr = cpu_to_be32(sc->id | ((u8)(sc->len / 4) << 24));
 343         nla_memcpy(sc->data, info->attrs[IOAM6_ATTR_SC_DATA], len);
 344
 345         err = rhashtable_lookup_insert_fast(&nsdata->schemas, &sc->head,
 346                                             rht_sc_params);
 347         if (err)
 348                 goto free_sc;
 349
 350 out_unlock:
 351         mutex_unlock(&nsdata->lock);
 352         return err;
 353 free_sc:
 354         kfree(sc);
 355         goto out_unlock;
 356 }
 357
 358 static int ioam6_genl_delsc(struct sk_buff *skb, struct genl_info *info)
 359 {
 360         struct ioam6_pernet_data *nsdata;
 361         struct ioam6_namespace *ns;
 362         struct ioam6_schema *sc;
 363         int err;
 364         u32 id;
 365
 366         if (!info->attrs[IOAM6_ATTR_SC_ID])
 367                 return -EINVAL;
 368
 369         id = nla_get_u32(info->attrs[IOAM6_ATTR_SC_ID]);
 370         nsdata = ioam6_pernet(genl_info_net(info));
 371
 372         mutex_lock(&nsdata->lock);
 373
 374         sc = rhashtable_lookup_fast(&nsdata->schemas, &id, rht_sc_params);
 375         if (!sc) {
 376                 err = -ENOENT;
 377                 goto out_unlock;
 378         }
 379
 380         ns = rcu_dereference_protected(sc->ns, lockdep_is_held(&nsdata->lock));
 381
 382         err = rhashtable_remove_fast(&nsdata->schemas, &sc->head,
 383                                      rht_sc_params);
 384         if (err)
 385                 goto out_unlock;
 386
 387         if (ns)
 388                 rcu_assign_pointer(ns->schema, NULL);
 389
 390         ioam6_sc_release(sc);
 391
 392 out_unlock:
 393         mutex_unlock(&nsdata->lock);
 394         return err;
 395 }
 396
 397 static int __ioam6_genl_dumpsc_element(struct ioam6_schema *sc,
 398                                        u32 portid, u32 seq, u32 flags,
 399                                        struct sk_buff *skb, u8 cmd)
 400 {
 401         struct ioam6_namespace *ns;
 402         void *hdr;
 403
 404         hdr = genlmsg_put(skb, portid, seq, &ioam6_genl_family, flags, cmd);
 405         if (!hdr)
 406                 return -ENOMEM;
 407
 408         if (nla_put_u32(skb, IOAM6_ATTR_SC_ID, sc->id) ||
 409             nla_put(skb, IOAM6_ATTR_SC_DATA, sc->len, sc->data))
 410                 goto nla_put_failure;
 411
 412         rcu_read_lock();
 413
 414         ns = rcu_dereference(sc->ns);
 415         if (ns && nla_put_u16(skb, IOAM6_ATTR_NS_ID, be16_to_cpu(ns->id))) {
 416                 rcu_read_unlock();
 417                 goto nla_put_failure;
 418         }
 419
 420         rcu_read_unlock();
 421
 422         genlmsg_end(skb, hdr);
 423         return 0;
 424
 425 nla_put_failure:
 426         genlmsg_cancel(skb, hdr);
 427         return -EMSGSIZE;
 428 }
 429
 430 static int ioam6_genl_dumpsc_start(struct netlink_callback *cb)
 431 {
 432         struct ioam6_pernet_data *nsdata = ioam6_pernet(sock_net(cb->skb->sk));
 433         struct rhashtable_iter *iter = (struct rhashtable_iter *)cb->args[0];
 434
 435         if (!iter) {
 436                 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
 437                 if (!iter)
 438                         return -ENOMEM;
 439
 440                 cb->args[0] = (long)iter;
 441         }
 442
 443         rhashtable_walk_enter(&nsdata->schemas, iter);
 444
 445         return 0;
 446 }
 447
 448 static int ioam6_genl_dumpsc_done(struct netlink_callback *cb)
 449 {
 450         struct rhashtable_iter *iter = (struct rhashtable_iter *)cb->args[0];
 451
 452         rhashtable_walk_exit(iter);
 453         kfree(iter);
 454
 455         return 0;
 456 }
 457
 458 static int ioam6_genl_dumpsc(struct sk_buff *skb, struct netlink_callback *cb)
 459 {
 460         struct rhashtable_iter *iter;
 461         struct ioam6_schema *sc;
 462         int err;
 463
 464         iter = (struct rhashtable_iter *)cb->args[0];
 465         rhashtable_walk_start(iter);
 466
 467         for (;;) {
 468                 sc = rhashtable_walk_next(iter);
 469
 470                 if (IS_ERR(sc)) {
 471                         if (PTR_ERR(sc) == -EAGAIN)
 472                                 continue;
 473                         err = PTR_ERR(sc);
 474                         goto done;
 475                 } else if (!sc) {
 476                         break;
 477                 }
 478
 479                 err = __ioam6_genl_dumpsc_element(sc,
 480                                                   NETLINK_CB(cb->skb).portid,
 481                                                   cb->nlh->nlmsg_seq,
 482                                                   NLM_F_MULTI,
 483                                                   skb,
 484                                                   IOAM6_CMD_DUMP_SCHEMAS);
 485                 if (err)
 486                         goto done;
 487         }
 488
 489         err = skb->len;
 490
 491 done:
 492         rhashtable_walk_stop(iter);
 493         return err;
 494 }
 495
 496 static int ioam6_genl_ns_set_schema(struct sk_buff *skb, struct genl_info *info)
 497 {
 498         struct ioam6_namespace *ns, *ns_ref;
 499         struct ioam6_schema *sc, *sc_ref;
 500         struct ioam6_pernet_data *nsdata;
 501         __be16 ns_id;
 502         u32 sc_id;
 503         int err;
 504
 505         if (!info->attrs[IOAM6_ATTR_NS_ID] ||
 506             (!info->attrs[IOAM6_ATTR_SC_ID] &&
 507              !info->attrs[IOAM6_ATTR_SC_NONE]))
 508                 return -EINVAL;
 509
 510         ns_id = cpu_to_be16(nla_get_u16(info->attrs[IOAM6_ATTR_NS_ID]));
 511         nsdata = ioam6_pernet(genl_info_net(info));
 512
 513         mutex_lock(&nsdata->lock);
 514
 515         ns = rhashtable_lookup_fast(&nsdata->namespaces, &ns_id, rht_ns_params);
 516         if (!ns) {
 517                 err = -ENOENT;
 518                 goto out_unlock;
 519         }
 520
 521         if (info->attrs[IOAM6_ATTR_SC_NONE]) {
 522                 sc = NULL;
 523         } else {
 524                 sc_id = nla_get_u32(info->attrs[IOAM6_ATTR_SC_ID]);
 525                 sc = rhashtable_lookup_fast(&nsdata->schemas, &sc_id,
 526                                             rht_sc_params);
 527                 if (!sc) {
 528                         err = -ENOENT;
 529                         goto out_unlock;
 530                 }
 531         }
 532
 533         sc_ref = rcu_dereference_protected(ns->schema,
 534                                            lockdep_is_held(&nsdata->lock));
 535         if (sc_ref)
 536                 rcu_assign_pointer(sc_ref->ns, NULL);
 537         rcu_assign_pointer(ns->schema, sc);
 538
 539         if (sc) {
 540                 ns_ref = rcu_dereference_protected(sc->ns,
 541                                                    lockdep_is_held(&nsdata->lock));
 542                 if (ns_ref)
 543                         rcu_assign_pointer(ns_ref->schema, NULL);
 544                 rcu_assign_pointer(sc->ns, ns);
 545         }
 546
 547         err = 0;
 548
 549 out_unlock:
 550         mutex_unlock(&nsdata->lock);
 551         return err;
 552 }
 553
 554 static const struct genl_ops ioam6_genl_ops[] = {
 555         {
 556                 .cmd    = IOAM6_CMD_ADD_NAMESPACE,
 557                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 558                 .doit   = ioam6_genl_addns,
 559                 .flags  = GENL_ADMIN_PERM,
 560                 .policy = ioam6_genl_policy_addns,
 561                 .maxattr = ARRAY_SIZE(ioam6_genl_policy_addns) - 1,
 562         },
 563         {
 564                 .cmd    = IOAM6_CMD_DEL_NAMESPACE,
 565                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 566                 .doit   = ioam6_genl_delns,
 567                 .flags  = GENL_ADMIN_PERM,
 568                 .policy = ioam6_genl_policy_delns,
 569                 .maxattr = ARRAY_SIZE(ioam6_genl_policy_delns) - 1,
 570         },
 571         {
 572                 .cmd    = IOAM6_CMD_DUMP_NAMESPACES,
 573                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 574                 .start  = ioam6_genl_dumpns_start,
 575                 .dumpit = ioam6_genl_dumpns,
 576                 .done   = ioam6_genl_dumpns_done,
 577                 .flags  = GENL_ADMIN_PERM,
 578         },
 579         {
 580                 .cmd    = IOAM6_CMD_ADD_SCHEMA,
 581                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 582                 .doit   = ioam6_genl_addsc,
 583                 .flags  = GENL_ADMIN_PERM,
 584                 .policy = ioam6_genl_policy_addsc,
 585                 .maxattr = ARRAY_SIZE(ioam6_genl_policy_addsc) - 1,
 586         },
 587         {
 588                 .cmd    = IOAM6_CMD_DEL_SCHEMA,
 589                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 590                 .doit   = ioam6_genl_delsc,
 591                 .flags  = GENL_ADMIN_PERM,
 592                 .policy = ioam6_genl_policy_delsc,
 593                 .maxattr = ARRAY_SIZE(ioam6_genl_policy_delsc) - 1,
 594         },
 595         {
 596                 .cmd    = IOAM6_CMD_DUMP_SCHEMAS,
 597                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 598                 .start  = ioam6_genl_dumpsc_start,
 599                 .dumpit = ioam6_genl_dumpsc,
 600                 .done   = ioam6_genl_dumpsc_done,
 601                 .flags  = GENL_ADMIN_PERM,
 602         },
 603         {
 604                 .cmd    = IOAM6_CMD_NS_SET_SCHEMA,
 605                 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 606                 .doit   = ioam6_genl_ns_set_schema,
 607                 .flags  = GENL_ADMIN_PERM,
 608                 .policy = ioam6_genl_policy_ns_sc,
 609                 .maxattr = ARRAY_SIZE(ioam6_genl_policy_ns_sc) - 1,
 610         },
 611 };
 612
 613 static struct genl_family ioam6_genl_family __ro_after_init = {
 614         .name           = IOAM6_GENL_NAME,
 615         .version        = IOAM6_GENL_VERSION,
 616         .netnsok        = true,
 617         .parallel_ops   = true,
 618         .ops            = ioam6_genl_ops,
 619         .n_ops          = ARRAY_SIZE(ioam6_genl_ops),
 620         .module         = THIS_MODULE,
 621 };
 622
 623 struct ioam6_namespace *ioam6_namespace(struct net *net, __be16 id)
 624 {
 625         struct ioam6_pernet_data *nsdata = ioam6_pernet(net);
 626
 627         return rhashtable_lookup_fast(&nsdata->namespaces, &id, rht_ns_params);
 628 }
 629
 630 static void __ioam6_fill_trace_data(struct sk_buff *skb,
 631                                     struct ioam6_namespace *ns,
 632                                     struct ioam6_trace_hdr *trace,
 633                                     struct ioam6_schema *sc,
 634                                     u8 sclen)
 635 {
 636         struct __kernel_sock_timeval ts;
 637         u64 raw64;
 638         u32 raw32;
 639         u16 raw16;
 640         u8 *data;
 641         u8 byte;
 642
 643         data = trace->data + trace->remlen * 4 - trace->nodelen * 4 - sclen * 4;
 644
 645         /* hop_lim and node_id */
 646         if (trace->type.bit0) {
 647                 byte = ipv6_hdr(skb)->hop_limit;
 648                 if (skb->dev)
 649                         byte--;
 650
 651                 raw32 = dev_net(skb_dst(skb)->dev)->ipv6.sysctl.ioam6_id;
 652
 653                 *(__be32 *)data = cpu_to_be32((byte << 24) | raw32);
 654                 data += sizeof(__be32);
 655         }
 656
 657         /* ingress_if_id and egress_if_id */
 658         if (trace->type.bit1) {
 659                 if (!skb->dev)
 660                         raw16 = IOAM6_U16_UNAVAILABLE;
 661                 else
 662                         raw16 = (__force u16)__in6_dev_get(skb->dev)->cnf.ioam6_id;
 663
 664                 *(__be16 *)data = cpu_to_be16(raw16);
 665                 data += sizeof(__be16);
 666
 667                 if (skb_dst(skb)->dev->flags & IFF_LOOPBACK)
 668                         raw16 = IOAM6_U16_UNAVAILABLE;
 669                 else
 670                         raw16 = (__force u16)__in6_dev_get(skb_dst(skb)->dev)->cnf.ioam6_id;
 671
 672                 *(__be16 *)data = cpu_to_be16(raw16);
 673                 data += sizeof(__be16);
 674         }
 675
 676         /* timestamp seconds */
 677         if (trace->type.bit2) {
 678                 if (!skb->dev) {
 679                         *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE);
 680                 } else {
 681                         if (!skb->tstamp)
 682                                 __net_timestamp(skb);
 683
 684                         skb_get_new_timestamp(skb, &ts);
 685                         *(__be32 *)data = cpu_to_be32((u32)ts.tv_sec);
 686                 }
 687                 data += sizeof(__be32);
 688         }
 689
 690         /* timestamp subseconds */
 691         if (trace->type.bit3) {
 692                 if (!skb->dev) {
 693                         *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE);
 694                 } else {
 695                         if (!skb->tstamp)
 696                                 __net_timestamp(skb);
 697
 698                         if (!trace->type.bit2)
 699                                 skb_get_new_timestamp(skb, &ts);
 700
 701                         *(__be32 *)data = cpu_to_be32((u32)ts.tv_usec);
 702                 }
 703                 data += sizeof(__be32);
 704         }
 705
 706         /* transit delay */
 707         if (trace->type.bit4) {
 708                 *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE);
 709                 data += sizeof(__be32);
 710         }
 711
 712         /* namespace data */
 713         if (trace->type.bit5) {
 714                 *(__be32 *)data = ns->data;
 715                 data += sizeof(__be32);
 716         }
 717
 718         /* queue depth */
 719         if (trace->type.bit6) {
 720                 *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE);
 721                 data += sizeof(__be32);
 722         }
 723
 724         /* checksum complement */
 725         if (trace->type.bit7) {
 726                 *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE);
 727                 data += sizeof(__be32);
 728         }
 729
 730         /* hop_lim and node_id (wide) */
 731         if (trace->type.bit8) {
 732                 byte = ipv6_hdr(skb)->hop_limit;
 733                 if (skb->dev)
 734                         byte--;
 735
 736                 raw64 = dev_net(skb_dst(skb)->dev)->ipv6.sysctl.ioam6_id_wide;
 737
 738                 *(__be64 *)data = cpu_to_be64(((u64)byte << 56) | raw64);
 739                 data += sizeof(__be64);
 740         }
 741
 742         /* ingress_if_id and egress_if_id (wide) */
 743         if (trace->type.bit9) {
 744                 if (!skb->dev)
 745                         raw32 = IOAM6_U32_UNAVAILABLE;
 746                 else
 747                         raw32 = __in6_dev_get(skb->dev)->cnf.ioam6_id_wide;
 748
 749                 *(__be32 *)data = cpu_to_be32(raw32);
 750                 data += sizeof(__be32);
 751
 752                 if (skb_dst(skb)->dev->flags & IFF_LOOPBACK)
 753                         raw32 = IOAM6_U32_UNAVAILABLE;
 754                 else
 755                         raw32 = __in6_dev_get(skb_dst(skb)->dev)->cnf.ioam6_id_wide;
 756
 757                 *(__be32 *)data = cpu_to_be32(raw32);
 758                 data += sizeof(__be32);
 759         }
 760
 761         /* namespace data (wide) */
 762         if (trace->type.bit10) {
 763                 *(__be64 *)data = ns->data_wide;
 764                 data += sizeof(__be64);
 765         }
 766
 767         /* buffer occupancy */
 768         if (trace->type.bit11) {
 769                 *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE);
 770                 data += sizeof(__be32);
 771         }
 772
 773         /* opaque state snapshot */
 774         if (trace->type.bit22) {
 775                 if (!sc) {
 776                         *(__be32 *)data = cpu_to_be32(IOAM6_U32_UNAVAILABLE >> 8);
 777                 } else {
 778                         *(__be32 *)data = sc->hdr;
 779                         data += sizeof(__be32);
 780
 781                         memcpy(data, sc->data, sc->len);
 782                 }
 783         }
 784 }
 785
 786 /* called with rcu_read_lock() */
 787 void ioam6_fill_trace_data(struct sk_buff *skb,
 788                            struct ioam6_namespace *ns,
 789                            struct ioam6_trace_hdr *trace)
 790 {
 791         struct ioam6_schema *sc;
 792         u8 sclen = 0;
 793
 794         /* Skip if Overflow flag is set OR
 795          * if an unknown type (bit 12-21) is set
 796          */
 797         if (trace->overflow ||
 798             trace->type.bit12 | trace->type.bit13 | trace->type.bit14 |
 799             trace->type.bit15 | trace->type.bit16 | trace->type.bit17 |
 800             trace->type.bit18 | trace->type.bit19 | trace->type.bit20 |
 801             trace->type.bit21) {
 802                 return;
 803         }
 804
 805         /* NodeLen does not include Opaque State Snapshot length. We need to
 806          * take it into account if the corresponding bit is set (bit 22) and
 807          * if the current IOAM namespace has an active schema attached to it
 808          */
 809         sc = rcu_dereference(ns->schema);
 810         if (trace->type.bit22) {
 811                 sclen = sizeof_field(struct ioam6_schema, hdr) / 4;
 812
 813                 if (sc)
 814                         sclen += sc->len / 4;
 815         }
 816
 817         /* If there is no space remaining, we set the Overflow flag and we
 818          * skip without filling the trace
 819          */
 820         if (!trace->remlen || trace->remlen < trace->nodelen + sclen) {
 821                 trace->overflow = 1;
 822                 return;
 823         }
 824
 825         __ioam6_fill_trace_data(skb, ns, trace, sc, sclen);
 826         trace->remlen -= trace->nodelen + sclen;
 827 }
 828
 829 static int __net_init ioam6_net_init(struct net *net)
 830 {
 831         struct ioam6_pernet_data *nsdata;
 832         int err = -ENOMEM;
 833
 834         nsdata = kzalloc(sizeof(*nsdata), GFP_KERNEL);
 835         if (!nsdata)
 836                 goto out;
 837
 838         mutex_init(&nsdata->lock);
 839         net->ipv6.ioam6_data = nsdata;
 840
 841         err = rhashtable_init(&nsdata->namespaces, &rht_ns_params);
 842         if (err)
 843                 goto free_nsdata;
 844
 845         err = rhashtable_init(&nsdata->schemas, &rht_sc_params);
 846         if (err)
 847                 goto free_rht_ns;
 848
 849 out:
 850         return err;
 851 free_rht_ns:
 852         rhashtable_destroy(&nsdata->namespaces);
 853 free_nsdata:
 854         kfree(nsdata);
 855         net->ipv6.ioam6_data = NULL;
 856         goto out;
 857 }
 858
 859 static void __net_exit ioam6_net_exit(struct net *net)
 860 {
 861         struct ioam6_pernet_data *nsdata = ioam6_pernet(net);
 862
 863         rhashtable_free_and_destroy(&nsdata->namespaces, ioam6_free_ns, NULL);
 864         rhashtable_free_and_destroy(&nsdata->schemas, ioam6_free_sc, NULL);
 865
 866         kfree(nsdata);
 867 }
 868
 869 static struct pernet_operations ioam6_net_ops = {
 870         .init = ioam6_net_init,
 871         .exit = ioam6_net_exit,
 872 };
 873
 874 int __init ioam6_init(void)
 875 {
 876         int err = register_pernet_subsys(&ioam6_net_ops);
 877         if (err)
 878                 goto out;
 879
 880         err = genl_register_family(&ioam6_genl_family);
 881         if (err)
 882                 goto out_unregister_pernet_subsys;
 883
 884 #ifdef CONFIG_IPV6_IOAM6_LWTUNNEL
 885         err = ioam6_iptunnel_init();
 886         if (err)
 887                 goto out_unregister_genl;
 888 #endif
 889
 890         pr_info("In-situ OAM (IOAM) with IPv6\n");
 891
 892 out:
 893         return err;
 894 #ifdef CONFIG_IPV6_IOAM6_LWTUNNEL
 895 out_unregister_genl:
 896         genl_unregister_family(&ioam6_genl_family);
 897 #endif
 898 out_unregister_pernet_subsys:
 899         unregister_pernet_subsys(&ioam6_net_ops);
 900         goto out;
 901 }
 902
 903 void ioam6_exit(void)
 904 {
 905 #ifdef CONFIG_IPV6_IOAM6_LWTUNNEL
 906         ioam6_iptunnel_exit();
 907 #endif
 908         genl_unregister_family(&ioam6_genl_family);
 909         unregister_pernet_subsys(&ioam6_net_ops);
 910 }