net/netlabel/netlabel_unlabeled.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * NetLabel Unlabeled Support
   4  *
   5  * This file defines functions for dealing with unlabeled packets for the
   6  * NetLabel system.  The NetLabel system manages static and dynamic label
   7  * mappings for network protocols such as CIPSO and RIPSO.
   8  *
   9  * Author: Paul Moore <paul@paul-moore.com>
  10  */
  11
  12 /*
  13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 - 2008
  14  */
  15
  16 #include <linux/types.h>
  17 #include <linux/rcupdate.h>
  18 #include <linux/list.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/socket.h>
  21 #include <linux/string.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/audit.h>
  24 #include <linux/in.h>
  25 #include <linux/in6.h>
  26 #include <linux/ip.h>
  27 #include <linux/ipv6.h>
  28 #include <linux/notifier.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/security.h>
  31 #include <linux/slab.h>
  32 #include <net/sock.h>
  33 #include <net/netlink.h>
  34 #include <net/genetlink.h>
  35 #include <net/ip.h>
  36 #include <net/ipv6.h>
  37 #include <net/net_namespace.h>
  38 #include <net/netlabel.h>
  39 #include <asm/bug.h>
  40 #include <linux/atomic.h>
  41
  42 #include "netlabel_user.h"
  43 #include "netlabel_addrlist.h"
  44 #include "netlabel_domainhash.h"
  45 #include "netlabel_unlabeled.h"
  46 #include "netlabel_mgmt.h"
  47
  48 /* NOTE: at present we always use init's network namespace since we don't
  49  *       presently support different namespaces even though the majority of
  50  *       the functions in this file are "namespace safe" */
  51
  52 /* The unlabeled connection hash table which we use to map network interfaces
  53  * and addresses of unlabeled packets to a user specified secid value for the
  54  * LSM.  The hash table is used to lookup the network interface entry
  55  * (struct netlbl_unlhsh_iface) and then the interface entry is used to
  56  * lookup an IP address match from an ordered list.  If a network interface
  57  * match can not be found in the hash table then the default entry
  58  * (netlbl_unlhsh_def) is used.  The IP address entry list
  59  * (struct netlbl_unlhsh_addr) is ordered such that the entries with a
  60  * larger netmask come first.
  61  */
  62 struct netlbl_unlhsh_tbl {
  63         struct list_head *tbl;
  64         u32 size;
  65 };
  66 #define netlbl_unlhsh_addr4_entry(iter) \
  67         container_of(iter, struct netlbl_unlhsh_addr4, list)
  68 struct netlbl_unlhsh_addr4 {
  69         u32 secid;
  70
  71         struct netlbl_af4list list;
  72         struct rcu_head rcu;
  73 };
  74 #define netlbl_unlhsh_addr6_entry(iter) \
  75         container_of(iter, struct netlbl_unlhsh_addr6, list)
  76 struct netlbl_unlhsh_addr6 {
  77         u32 secid;
  78
  79         struct netlbl_af6list list;
  80         struct rcu_head rcu;
  81 };
  82 struct netlbl_unlhsh_iface {
  83         int ifindex;
  84         struct list_head addr4_list;
  85         struct list_head addr6_list;
  86
  87         u32 valid;
  88         struct list_head list;
  89         struct rcu_head rcu;
  90 };
  91
  92 /* Argument struct for netlbl_unlhsh_walk() */
  93 struct netlbl_unlhsh_walk_arg {
  94         struct netlink_callback *nl_cb;
  95         struct sk_buff *skb;
  96         u32 seq;
  97 };
  98
  99 /* Unlabeled connection hash table */
 100 /* updates should be so rare that having one spinlock for the entire
 101  * hash table should be okay */
 102 static DEFINE_SPINLOCK(netlbl_unlhsh_lock);
 103 #define netlbl_unlhsh_rcu_deref(p) \
 104         rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock))
 105 static struct netlbl_unlhsh_tbl __rcu *netlbl_unlhsh;
 106 static struct netlbl_unlhsh_iface __rcu *netlbl_unlhsh_def;
 107
 108 /* Accept unlabeled packets flag */
 109 static u8 netlabel_unlabel_acceptflg;
 110
 111 /* NetLabel Generic NETLINK unlabeled family */
 112 static struct genl_family netlbl_unlabel_gnl_family;
 113
 114 /* NetLabel Netlink attribute policy */
 115 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
 116         [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
 117         [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
 118                                       .len = sizeof(struct in6_addr) },
 119         [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
 120                                       .len = sizeof(struct in6_addr) },
 121         [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
 122                                       .len = sizeof(struct in_addr) },
 123         [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
 124                                       .len = sizeof(struct in_addr) },
 125         [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
 126                                    .len = IFNAMSIZ - 1 },
 127         [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
 128 };
 129
 130 /*
 131  * Unlabeled Connection Hash Table Functions
 132  */
 133
 134 /**
 135  * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
 136  * @entry: the entry's RCU field
 137  *
 138  * Description:
 139  * This function is designed to be used as a callback to the call_rcu()
 140  * function so that memory allocated to a hash table interface entry can be
 141  * released safely.  It is important to note that this function does not free
 142  * the IPv4 and IPv6 address lists contained as part of an interface entry.  It
 143  * is up to the rest of the code to make sure an interface entry is only freed
 144  * once it's address lists are empty.
 145  *
 146  */
 147 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
 148 {
 149         struct netlbl_unlhsh_iface *iface;
 150         struct netlbl_af4list *iter4;
 151         struct netlbl_af4list *tmp4;
 152 #if IS_ENABLED(CONFIG_IPV6)
 153         struct netlbl_af6list *iter6;
 154         struct netlbl_af6list *tmp6;
 155 #endif /* IPv6 */
 156
 157         iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
 158
 159         /* no need for locks here since we are the only one with access to this
 160          * structure */
 161
 162         netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
 163                 netlbl_af4list_remove_entry(iter4);
 164                 kfree(netlbl_unlhsh_addr4_entry(iter4));
 165         }
 166 #if IS_ENABLED(CONFIG_IPV6)
 167         netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
 168                 netlbl_af6list_remove_entry(iter6);
 169                 kfree(netlbl_unlhsh_addr6_entry(iter6));
 170         }
 171 #endif /* IPv6 */
 172         kfree(iface);
 173 }
 174
 175 /**
 176  * netlbl_unlhsh_hash - Hashing function for the hash table
 177  * @ifindex: the network interface/device to hash
 178  *
 179  * Description:
 180  * This is the hashing function for the unlabeled hash table, it returns the
 181  * bucket number for the given device/interface.  The caller is responsible for
 182  * ensuring that the hash table is protected with either a RCU read lock or
 183  * the hash table lock.
 184  *
 185  */
 186 static u32 netlbl_unlhsh_hash(int ifindex)
 187 {
 188         return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1);
 189 }
 190
 191 /**
 192  * netlbl_unlhsh_search_iface - Search for a matching interface entry
 193  * @ifindex: the network interface
 194  *
 195  * Description:
 196  * Searches the unlabeled connection hash table and returns a pointer to the
 197  * interface entry which matches @ifindex, otherwise NULL is returned.  The
 198  * caller is responsible for ensuring that the hash table is protected with
 199  * either a RCU read lock or the hash table lock.
 200  *
 201  */
 202 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
 203 {
 204         u32 bkt;
 205         struct list_head *bkt_list;
 206         struct netlbl_unlhsh_iface *iter;
 207
 208         bkt = netlbl_unlhsh_hash(ifindex);
 209         bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt];
 210         list_for_each_entry_rcu(iter, bkt_list, list)
 211                 if (iter->valid && iter->ifindex == ifindex)
 212                         return iter;
 213
 214         return NULL;
 215 }
 216
 217 /**
 218  * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
 219  * @iface: the associated interface entry
 220  * @addr: IPv4 address in network byte order
 221  * @mask: IPv4 address mask in network byte order
 222  * @secid: LSM secid value for entry
 223  *
 224  * Description:
 225  * Add a new address entry into the unlabeled connection hash table using the
 226  * interface entry specified by @iface.  On success zero is returned, otherwise
 227  * a negative value is returned.
 228  *
 229  */
 230 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
 231                                    const struct in_addr *addr,
 232                                    const struct in_addr *mask,
 233                                    u32 secid)
 234 {
 235         int ret_val;
 236         struct netlbl_unlhsh_addr4 *entry;
 237
 238         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 239         if (entry == NULL)
 240                 return -ENOMEM;
 241
 242         entry->list.addr = addr->s_addr & mask->s_addr;
 243         entry->list.mask = mask->s_addr;
 244         entry->list.valid = 1;
 245         entry->secid = secid;
 246
 247         spin_lock(&netlbl_unlhsh_lock);
 248         ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
 249         spin_unlock(&netlbl_unlhsh_lock);
 250
 251         if (ret_val != 0)
 252                 kfree(entry);
 253         return ret_val;
 254 }
 255
 256 #if IS_ENABLED(CONFIG_IPV6)
 257 /**
 258  * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
 259  * @iface: the associated interface entry
 260  * @addr: IPv6 address in network byte order
 261  * @mask: IPv6 address mask in network byte order
 262  * @secid: LSM secid value for entry
 263  *
 264  * Description:
 265  * Add a new address entry into the unlabeled connection hash table using the
 266  * interface entry specified by @iface.  On success zero is returned, otherwise
 267  * a negative value is returned.
 268  *
 269  */
 270 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
 271                                    const struct in6_addr *addr,
 272                                    const struct in6_addr *mask,
 273                                    u32 secid)
 274 {
 275         int ret_val;
 276         struct netlbl_unlhsh_addr6 *entry;
 277
 278         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 279         if (entry == NULL)
 280                 return -ENOMEM;
 281
 282         entry->list.addr = *addr;
 283         entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
 284         entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
 285         entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
 286         entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
 287         entry->list.mask = *mask;
 288         entry->list.valid = 1;
 289         entry->secid = secid;
 290
 291         spin_lock(&netlbl_unlhsh_lock);
 292         ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
 293         spin_unlock(&netlbl_unlhsh_lock);
 294
 295         if (ret_val != 0)
 296                 kfree(entry);
 297         return 0;
 298 }
 299 #endif /* IPv6 */
 300
 301 /**
 302  * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
 303  * @ifindex: network interface
 304  *
 305  * Description:
 306  * Add a new, empty, interface entry into the unlabeled connection hash table.
 307  * On success a pointer to the new interface entry is returned, on failure NULL
 308  * is returned.
 309  *
 310  */
 311 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
 312 {
 313         u32 bkt;
 314         struct netlbl_unlhsh_iface *iface;
 315
 316         iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
 317         if (iface == NULL)
 318                 return NULL;
 319
 320         iface->ifindex = ifindex;
 321         INIT_LIST_HEAD(&iface->addr4_list);
 322         INIT_LIST_HEAD(&iface->addr6_list);
 323         iface->valid = 1;
 324
 325         spin_lock(&netlbl_unlhsh_lock);
 326         if (ifindex > 0) {
 327                 bkt = netlbl_unlhsh_hash(ifindex);
 328                 if (netlbl_unlhsh_search_iface(ifindex) != NULL)
 329                         goto add_iface_failure;
 330                 list_add_tail_rcu(&iface->list,
 331                              &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]);
 332         } else {
 333                 INIT_LIST_HEAD(&iface->list);
 334                 if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL)
 335                         goto add_iface_failure;
 336                 rcu_assign_pointer(netlbl_unlhsh_def, iface);
 337         }
 338         spin_unlock(&netlbl_unlhsh_lock);
 339
 340         return iface;
 341
 342 add_iface_failure:
 343         spin_unlock(&netlbl_unlhsh_lock);
 344         kfree(iface);
 345         return NULL;
 346 }
 347
 348 /**
 349  * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
 350  * @net: network namespace
 351  * @dev_name: interface name
 352  * @addr: IP address in network byte order
 353  * @mask: address mask in network byte order
 354  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
 355  * @secid: LSM secid value for the entry
 356  * @audit_info: NetLabel audit information
 357  *
 358  * Description:
 359  * Adds a new entry to the unlabeled connection hash table.  Returns zero on
 360  * success, negative values on failure.
 361  *
 362  */
 363 int netlbl_unlhsh_add(struct net *net,
 364                       const char *dev_name,
 365                       const void *addr,
 366                       const void *mask,
 367                       u32 addr_len,
 368                       u32 secid,
 369                       struct netlbl_audit *audit_info)
 370 {
 371         int ret_val;
 372         int ifindex;
 373         struct net_device *dev;
 374         struct netlbl_unlhsh_iface *iface;
 375         struct audit_buffer *audit_buf = NULL;
 376         char *secctx = NULL;
 377         u32 secctx_len;
 378
 379         if (addr_len != sizeof(struct in_addr) &&
 380             addr_len != sizeof(struct in6_addr))
 381                 return -EINVAL;
 382
 383         rcu_read_lock();
 384         if (dev_name != NULL) {
 385                 dev = dev_get_by_name_rcu(net, dev_name);
 386                 if (dev == NULL) {
 387                         ret_val = -ENODEV;
 388                         goto unlhsh_add_return;
 389                 }
 390                 ifindex = dev->ifindex;
 391                 iface = netlbl_unlhsh_search_iface(ifindex);
 392         } else {
 393                 ifindex = 0;
 394                 iface = rcu_dereference(netlbl_unlhsh_def);
 395         }
 396         if (iface == NULL) {
 397                 iface = netlbl_unlhsh_add_iface(ifindex);
 398                 if (iface == NULL) {
 399                         ret_val = -ENOMEM;
 400                         goto unlhsh_add_return;
 401                 }
 402         }
 403         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
 404                                               audit_info);
 405         switch (addr_len) {
 406         case sizeof(struct in_addr): {
 407                 const struct in_addr *addr4 = addr;
 408                 const struct in_addr *mask4 = mask;
 409
 410                 ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
 411                 if (audit_buf != NULL)
 412                         netlbl_af4list_audit_addr(audit_buf, 1,
 413                                                   dev_name,
 414                                                   addr4->s_addr,
 415                                                   mask4->s_addr);
 416                 break;
 417         }
 418 #if IS_ENABLED(CONFIG_IPV6)
 419         case sizeof(struct in6_addr): {
 420                 const struct in6_addr *addr6 = addr;
 421                 const struct in6_addr *mask6 = mask;
 422
 423                 ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
 424                 if (audit_buf != NULL)
 425                         netlbl_af6list_audit_addr(audit_buf, 1,
 426                                                   dev_name,
 427                                                   addr6, mask6);
 428                 break;
 429         }
 430 #endif /* IPv6 */
 431         default:
 432                 ret_val = -EINVAL;
 433         }
 434         if (ret_val == 0)
 435                 atomic_inc(&netlabel_mgmt_protocount);
 436
 437 unlhsh_add_return:
 438         rcu_read_unlock();
 439         if (audit_buf != NULL) {
 440                 if (security_secid_to_secctx(secid,
 441                                              &secctx,
 442                                              &secctx_len) == 0) {
 443                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 444                         security_release_secctx(secctx, secctx_len);
 445                 }
 446                 audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
 447                 audit_log_end(audit_buf);
 448         }
 449         return ret_val;
 450 }
 451
 452 /**
 453  * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
 454  * @net: network namespace
 455  * @iface: interface entry
 456  * @addr: IP address
 457  * @mask: IP address mask
 458  * @audit_info: NetLabel audit information
 459  *
 460  * Description:
 461  * Remove an IP address entry from the unlabeled connection hash table.
 462  * Returns zero on success, negative values on failure.
 463  *
 464  */
 465 static int netlbl_unlhsh_remove_addr4(struct net *net,
 466                                       struct netlbl_unlhsh_iface *iface,
 467                                       const struct in_addr *addr,
 468                                       const struct in_addr *mask,
 469                                       struct netlbl_audit *audit_info)
 470 {
 471         struct netlbl_af4list *list_entry;
 472         struct netlbl_unlhsh_addr4 *entry;
 473         struct audit_buffer *audit_buf;
 474         struct net_device *dev;
 475         char *secctx;
 476         u32 secctx_len;
 477
 478         spin_lock(&netlbl_unlhsh_lock);
 479         list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
 480                                            &iface->addr4_list);
 481         spin_unlock(&netlbl_unlhsh_lock);
 482         if (list_entry != NULL)
 483                 entry = netlbl_unlhsh_addr4_entry(list_entry);
 484         else
 485                 entry = NULL;
 486
 487         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
 488                                               audit_info);
 489         if (audit_buf != NULL) {
 490                 dev = dev_get_by_index(net, iface->ifindex);
 491                 netlbl_af4list_audit_addr(audit_buf, 1,
 492                                           (dev != NULL ? dev->name : NULL),
 493                                           addr->s_addr, mask->s_addr);
 494                 if (dev != NULL)
 495                         dev_put(dev);
 496                 if (entry != NULL &&
 497                     security_secid_to_secctx(entry->secid,
 498                                              &secctx, &secctx_len) == 0) {
 499                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 500                         security_release_secctx(secctx, secctx_len);
 501                 }
 502                 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 503                 audit_log_end(audit_buf);
 504         }
 505
 506         if (entry == NULL)
 507                 return -ENOENT;
 508
 509         kfree_rcu(entry, rcu);
 510         return 0;
 511 }
 512
 513 #if IS_ENABLED(CONFIG_IPV6)
 514 /**
 515  * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
 516  * @net: network namespace
 517  * @iface: interface entry
 518  * @addr: IP address
 519  * @mask: IP address mask
 520  * @audit_info: NetLabel audit information
 521  *
 522  * Description:
 523  * Remove an IP address entry from the unlabeled connection hash table.
 524  * Returns zero on success, negative values on failure.
 525  *
 526  */
 527 static int netlbl_unlhsh_remove_addr6(struct net *net,
 528                                       struct netlbl_unlhsh_iface *iface,
 529                                       const struct in6_addr *addr,
 530                                       const struct in6_addr *mask,
 531                                       struct netlbl_audit *audit_info)
 532 {
 533         struct netlbl_af6list *list_entry;
 534         struct netlbl_unlhsh_addr6 *entry;
 535         struct audit_buffer *audit_buf;
 536         struct net_device *dev;
 537         char *secctx;
 538         u32 secctx_len;
 539
 540         spin_lock(&netlbl_unlhsh_lock);
 541         list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
 542         spin_unlock(&netlbl_unlhsh_lock);
 543         if (list_entry != NULL)
 544                 entry = netlbl_unlhsh_addr6_entry(list_entry);
 545         else
 546                 entry = NULL;
 547
 548         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
 549                                               audit_info);
 550         if (audit_buf != NULL) {
 551                 dev = dev_get_by_index(net, iface->ifindex);
 552                 netlbl_af6list_audit_addr(audit_buf, 1,
 553                                           (dev != NULL ? dev->name : NULL),
 554                                           addr, mask);
 555                 if (dev != NULL)
 556                         dev_put(dev);
 557                 if (entry != NULL &&
 558                     security_secid_to_secctx(entry->secid,
 559                                              &secctx, &secctx_len) == 0) {
 560                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 561                         security_release_secctx(secctx, secctx_len);
 562                 }
 563                 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 564                 audit_log_end(audit_buf);
 565         }
 566
 567         if (entry == NULL)
 568                 return -ENOENT;
 569
 570         kfree_rcu(entry, rcu);
 571         return 0;
 572 }
 573 #endif /* IPv6 */
 574
 575 /**
 576  * netlbl_unlhsh_condremove_iface - Remove an interface entry
 577  * @iface: the interface entry
 578  *
 579  * Description:
 580  * Remove an interface entry from the unlabeled connection hash table if it is
 581  * empty.  An interface entry is considered to be empty if there are no
 582  * address entries assigned to it.
 583  *
 584  */
 585 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
 586 {
 587         struct netlbl_af4list *iter4;
 588 #if IS_ENABLED(CONFIG_IPV6)
 589         struct netlbl_af6list *iter6;
 590 #endif /* IPv6 */
 591
 592         spin_lock(&netlbl_unlhsh_lock);
 593         netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
 594                 goto unlhsh_condremove_failure;
 595 #if IS_ENABLED(CONFIG_IPV6)
 596         netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
 597                 goto unlhsh_condremove_failure;
 598 #endif /* IPv6 */
 599         iface->valid = 0;
 600         if (iface->ifindex > 0)
 601                 list_del_rcu(&iface->list);
 602         else
 603                 RCU_INIT_POINTER(netlbl_unlhsh_def, NULL);
 604         spin_unlock(&netlbl_unlhsh_lock);
 605
 606         call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
 607         return;
 608
 609 unlhsh_condremove_failure:
 610         spin_unlock(&netlbl_unlhsh_lock);
 611 }
 612
 613 /**
 614  * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
 615  * @net: network namespace
 616  * @dev_name: interface name
 617  * @addr: IP address in network byte order
 618  * @mask: address mask in network byte order
 619  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
 620  * @audit_info: NetLabel audit information
 621  *
 622  * Description:
 623  * Removes and existing entry from the unlabeled connection hash table.
 624  * Returns zero on success, negative values on failure.
 625  *
 626  */
 627 int netlbl_unlhsh_remove(struct net *net,
 628                          const char *dev_name,
 629                          const void *addr,
 630                          const void *mask,
 631                          u32 addr_len,
 632                          struct netlbl_audit *audit_info)
 633 {
 634         int ret_val;
 635         struct net_device *dev;
 636         struct netlbl_unlhsh_iface *iface;
 637
 638         if (addr_len != sizeof(struct in_addr) &&
 639             addr_len != sizeof(struct in6_addr))
 640                 return -EINVAL;
 641
 642         rcu_read_lock();
 643         if (dev_name != NULL) {
 644                 dev = dev_get_by_name_rcu(net, dev_name);
 645                 if (dev == NULL) {
 646                         ret_val = -ENODEV;
 647                         goto unlhsh_remove_return;
 648                 }
 649                 iface = netlbl_unlhsh_search_iface(dev->ifindex);
 650         } else
 651                 iface = rcu_dereference(netlbl_unlhsh_def);
 652         if (iface == NULL) {
 653                 ret_val = -ENOENT;
 654                 goto unlhsh_remove_return;
 655         }
 656         switch (addr_len) {
 657         case sizeof(struct in_addr):
 658                 ret_val = netlbl_unlhsh_remove_addr4(net,
 659                                                      iface, addr, mask,
 660                                                      audit_info);
 661                 break;
 662 #if IS_ENABLED(CONFIG_IPV6)
 663         case sizeof(struct in6_addr):
 664                 ret_val = netlbl_unlhsh_remove_addr6(net,
 665                                                      iface, addr, mask,
 666                                                      audit_info);
 667                 break;
 668 #endif /* IPv6 */
 669         default:
 670                 ret_val = -EINVAL;
 671         }
 672         if (ret_val == 0) {
 673                 netlbl_unlhsh_condremove_iface(iface);
 674                 atomic_dec(&netlabel_mgmt_protocount);
 675         }
 676
 677 unlhsh_remove_return:
 678         rcu_read_unlock();
 679         return ret_val;
 680 }
 681
 682 /*
 683  * General Helper Functions
 684  */
 685
 686 /**
 687  * netlbl_unlhsh_netdev_handler - Network device notification handler
 688  * @this: notifier block
 689  * @event: the event
 690  * @ptr: the netdevice notifier info (cast to void)
 691  *
 692  * Description:
 693  * Handle network device events, although at present all we care about is a
 694  * network device going away.  In the case of a device going away we clear any
 695  * related entries from the unlabeled connection hash table.
 696  *
 697  */
 698 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
 699                                         unsigned long event, void *ptr)
 700 {
 701         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 702         struct netlbl_unlhsh_iface *iface = NULL;
 703
 704         if (!net_eq(dev_net(dev), &init_net))
 705                 return NOTIFY_DONE;
 706
 707         /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
 708         if (event == NETDEV_DOWN) {
 709                 spin_lock(&netlbl_unlhsh_lock);
 710                 iface = netlbl_unlhsh_search_iface(dev->ifindex);
 711                 if (iface != NULL && iface->valid) {
 712                         iface->valid = 0;
 713                         list_del_rcu(&iface->list);
 714                 } else
 715                         iface = NULL;
 716                 spin_unlock(&netlbl_unlhsh_lock);
 717         }
 718
 719         if (iface != NULL)
 720                 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
 721
 722         return NOTIFY_DONE;
 723 }
 724
 725 /**
 726  * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
 727  * @value: desired value
 728  * @audit_info: NetLabel audit information
 729  *
 730  * Description:
 731  * Set the value of the unlabeled accept flag to @value.
 732  *
 733  */
 734 static void netlbl_unlabel_acceptflg_set(u8 value,
 735                                          struct netlbl_audit *audit_info)
 736 {
 737         struct audit_buffer *audit_buf;
 738         u8 old_val;
 739
 740         old_val = netlabel_unlabel_acceptflg;
 741         netlabel_unlabel_acceptflg = value;
 742         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
 743                                               audit_info);
 744         if (audit_buf != NULL) {
 745                 audit_log_format(audit_buf,
 746                                  " unlbl_accept=%u old=%u", value, old_val);
 747                 audit_log_end(audit_buf);
 748         }
 749 }
 750
 751 /**
 752  * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
 753  * @info: the Generic NETLINK info block
 754  * @addr: the IP address
 755  * @mask: the IP address mask
 756  * @len: the address length
 757  *
 758  * Description:
 759  * Examine the Generic NETLINK message and extract the IP address information.
 760  * Returns zero on success, negative values on failure.
 761  *
 762  */
 763 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
 764                                        void **addr,
 765                                        void **mask,
 766                                        u32 *len)
 767 {
 768         u32 addr_len;
 769
 770         if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR] &&
 771             info->attrs[NLBL_UNLABEL_A_IPV4MASK]) {
 772                 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
 773                 if (addr_len != sizeof(struct in_addr) &&
 774                     addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
 775                         return -EINVAL;
 776                 *len = addr_len;
 777                 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
 778                 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
 779                 return 0;
 780         } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
 781                 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
 782                 if (addr_len != sizeof(struct in6_addr) &&
 783                     addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
 784                         return -EINVAL;
 785                 *len = addr_len;
 786                 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
 787                 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
 788                 return 0;
 789         }
 790
 791         return -EINVAL;
 792 }
 793
 794 /*
 795  * NetLabel Command Handlers
 796  */
 797
 798 /**
 799  * netlbl_unlabel_accept - Handle an ACCEPT message
 800  * @skb: the NETLINK buffer
 801  * @info: the Generic NETLINK info block
 802  *
 803  * Description:
 804  * Process a user generated ACCEPT message and set the accept flag accordingly.
 805  * Returns zero on success, negative values on failure.
 806  *
 807  */
 808 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
 809 {
 810         u8 value;
 811         struct netlbl_audit audit_info;
 812
 813         if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
 814                 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
 815                 if (value == 1 || value == 0) {
 816                         netlbl_netlink_auditinfo(skb, &audit_info);
 817                         netlbl_unlabel_acceptflg_set(value, &audit_info);
 818                         return 0;
 819                 }
 820         }
 821
 822         return -EINVAL;
 823 }
 824
 825 /**
 826  * netlbl_unlabel_list - Handle a LIST message
 827  * @skb: the NETLINK buffer
 828  * @info: the Generic NETLINK info block
 829  *
 830  * Description:
 831  * Process a user generated LIST message and respond with the current status.
 832  * Returns zero on success, negative values on failure.
 833  *
 834  */
 835 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
 836 {
 837         int ret_val = -EINVAL;
 838         struct sk_buff *ans_skb;
 839         void *data;
 840
 841         ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 842         if (ans_skb == NULL)
 843                 goto list_failure;
 844         data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
 845                                  0, NLBL_UNLABEL_C_LIST);
 846         if (data == NULL) {
 847                 ret_val = -ENOMEM;
 848                 goto list_failure;
 849         }
 850
 851         ret_val = nla_put_u8(ans_skb,
 852                              NLBL_UNLABEL_A_ACPTFLG,
 853                              netlabel_unlabel_acceptflg);
 854         if (ret_val != 0)
 855                 goto list_failure;
 856
 857         genlmsg_end(ans_skb, data);
 858         return genlmsg_reply(ans_skb, info);
 859
 860 list_failure:
 861         kfree_skb(ans_skb);
 862         return ret_val;
 863 }
 864
 865 /**
 866  * netlbl_unlabel_staticadd - Handle a STATICADD message
 867  * @skb: the NETLINK buffer
 868  * @info: the Generic NETLINK info block
 869  *
 870  * Description:
 871  * Process a user generated STATICADD message and add a new unlabeled
 872  * connection entry to the hash table.  Returns zero on success, negative
 873  * values on failure.
 874  *
 875  */
 876 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
 877                                     struct genl_info *info)
 878 {
 879         int ret_val;
 880         char *dev_name;
 881         void *addr;
 882         void *mask;
 883         u32 addr_len;
 884         u32 secid;
 885         struct netlbl_audit audit_info;
 886
 887         /* Don't allow users to add both IPv4 and IPv6 addresses for a
 888          * single entry.  However, allow users to create two entries, one each
 889          * for IPv4 and IPv4, with the same LSM security context which should
 890          * achieve the same result. */
 891         if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
 892             !info->attrs[NLBL_UNLABEL_A_IFACE] ||
 893             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 894                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 895               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 896                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 897                 return -EINVAL;
 898
 899         netlbl_netlink_auditinfo(skb, &audit_info);
 900
 901         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 902         if (ret_val != 0)
 903                 return ret_val;
 904         dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
 905         ret_val = security_secctx_to_secid(
 906                                   nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 907                                   nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 908                                   &secid);
 909         if (ret_val != 0)
 910                 return ret_val;
 911
 912         return netlbl_unlhsh_add(&init_net,
 913                                  dev_name, addr, mask, addr_len, secid,
 914                                  &audit_info);
 915 }
 916
 917 /**
 918  * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
 919  * @skb: the NETLINK buffer
 920  * @info: the Generic NETLINK info block
 921  *
 922  * Description:
 923  * Process a user generated STATICADDDEF message and add a new default
 924  * unlabeled connection entry.  Returns zero on success, negative values on
 925  * failure.
 926  *
 927  */
 928 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
 929                                        struct genl_info *info)
 930 {
 931         int ret_val;
 932         void *addr;
 933         void *mask;
 934         u32 addr_len;
 935         u32 secid;
 936         struct netlbl_audit audit_info;
 937
 938         /* Don't allow users to add both IPv4 and IPv6 addresses for a
 939          * single entry.  However, allow users to create two entries, one each
 940          * for IPv4 and IPv6, with the same LSM security context which should
 941          * achieve the same result. */
 942         if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
 943             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 944                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 945               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 946                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 947                 return -EINVAL;
 948
 949         netlbl_netlink_auditinfo(skb, &audit_info);
 950
 951         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 952         if (ret_val != 0)
 953                 return ret_val;
 954         ret_val = security_secctx_to_secid(
 955                                   nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 956                                   nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 957                                   &secid);
 958         if (ret_val != 0)
 959                 return ret_val;
 960
 961         return netlbl_unlhsh_add(&init_net,
 962                                  NULL, addr, mask, addr_len, secid,
 963                                  &audit_info);
 964 }
 965
 966 /**
 967  * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
 968  * @skb: the NETLINK buffer
 969  * @info: the Generic NETLINK info block
 970  *
 971  * Description:
 972  * Process a user generated STATICREMOVE message and remove the specified
 973  * unlabeled connection entry.  Returns zero on success, negative values on
 974  * failure.
 975  *
 976  */
 977 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
 978                                        struct genl_info *info)
 979 {
 980         int ret_val;
 981         char *dev_name;
 982         void *addr;
 983         void *mask;
 984         u32 addr_len;
 985         struct netlbl_audit audit_info;
 986
 987         /* See the note in netlbl_unlabel_staticadd() about not allowing both
 988          * IPv4 and IPv6 in the same entry. */
 989         if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
 990             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 991                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 992               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 993                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 994                 return -EINVAL;
 995
 996         netlbl_netlink_auditinfo(skb, &audit_info);
 997
 998         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 999         if (ret_val != 0)
1000                 return ret_val;
1001         dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1002
1003         return netlbl_unlhsh_remove(&init_net,
1004                                     dev_name, addr, mask, addr_len,
1005                                     &audit_info);
1006 }
1007
1008 /**
1009  * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1010  * @skb: the NETLINK buffer
1011  * @info: the Generic NETLINK info block
1012  *
1013  * Description:
1014  * Process a user generated STATICREMOVEDEF message and remove the default
1015  * unlabeled connection entry.  Returns zero on success, negative values on
1016  * failure.
1017  *
1018  */
1019 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1020                                           struct genl_info *info)
1021 {
1022         int ret_val;
1023         void *addr;
1024         void *mask;
1025         u32 addr_len;
1026         struct netlbl_audit audit_info;
1027
1028         /* See the note in netlbl_unlabel_staticadd() about not allowing both
1029          * IPv4 and IPv6 in the same entry. */
1030         if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1031                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1032               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1033                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1034                 return -EINVAL;
1035
1036         netlbl_netlink_auditinfo(skb, &audit_info);
1037
1038         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1039         if (ret_val != 0)
1040                 return ret_val;
1041
1042         return netlbl_unlhsh_remove(&init_net,
1043                                     NULL, addr, mask, addr_len,
1044                                     &audit_info);
1045 }
1046
1047
1048 /**
1049  * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1050  * @cmd: command/message
1051  * @iface: the interface entry
1052  * @addr4: the IPv4 address entry
1053  * @addr6: the IPv6 address entry
1054  * @arg: the netlbl_unlhsh_walk_arg structure
1055  *
1056  * Description:
1057  * This function is designed to be used to generate a response for a
1058  * STATICLIST or STATICLISTDEF message.  When called either @addr4 or @addr6
1059  * can be specified, not both, the other unspecified entry should be set to
1060  * NULL by the caller.  Returns the size of the message on success, negative
1061  * values on failure.
1062  *
1063  */
1064 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1065                                        const struct netlbl_unlhsh_iface *iface,
1066                                        const struct netlbl_unlhsh_addr4 *addr4,
1067                                        const struct netlbl_unlhsh_addr6 *addr6,
1068                                        void *arg)
1069 {
1070         int ret_val = -ENOMEM;
1071         struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1072         struct net_device *dev;
1073         void *data;
1074         u32 secid;
1075         char *secctx;
1076         u32 secctx_len;
1077
1078         data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
1079                            cb_arg->seq, &netlbl_unlabel_gnl_family,
1080                            NLM_F_MULTI, cmd);
1081         if (data == NULL)
1082                 goto list_cb_failure;
1083
1084         if (iface->ifindex > 0) {
1085                 dev = dev_get_by_index(&init_net, iface->ifindex);
1086                 if (!dev) {
1087                         ret_val = -ENODEV;
1088                         goto list_cb_failure;
1089                 }
1090                 ret_val = nla_put_string(cb_arg->skb,
1091                                          NLBL_UNLABEL_A_IFACE, dev->name);
1092                 dev_put(dev);
1093                 if (ret_val != 0)
1094                         goto list_cb_failure;
1095         }
1096
1097         if (addr4) {
1098                 struct in_addr addr_struct;
1099
1100                 addr_struct.s_addr = addr4->list.addr;
1101                 ret_val = nla_put_in_addr(cb_arg->skb,
1102                                           NLBL_UNLABEL_A_IPV4ADDR,
1103                                           addr_struct.s_addr);
1104                 if (ret_val != 0)
1105                         goto list_cb_failure;
1106
1107                 addr_struct.s_addr = addr4->list.mask;
1108                 ret_val = nla_put_in_addr(cb_arg->skb,
1109                                           NLBL_UNLABEL_A_IPV4MASK,
1110                                           addr_struct.s_addr);
1111                 if (ret_val != 0)
1112                         goto list_cb_failure;
1113
1114                 secid = addr4->secid;
1115         } else {
1116                 ret_val = nla_put_in6_addr(cb_arg->skb,
1117                                            NLBL_UNLABEL_A_IPV6ADDR,
1118                                            &addr6->list.addr);
1119                 if (ret_val != 0)
1120                         goto list_cb_failure;
1121
1122                 ret_val = nla_put_in6_addr(cb_arg->skb,
1123                                            NLBL_UNLABEL_A_IPV6MASK,
1124                                            &addr6->list.mask);
1125                 if (ret_val != 0)
1126                         goto list_cb_failure;
1127
1128                 secid = addr6->secid;
1129         }
1130
1131         ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1132         if (ret_val != 0)
1133                 goto list_cb_failure;
1134         ret_val = nla_put(cb_arg->skb,
1135                           NLBL_UNLABEL_A_SECCTX,
1136                           secctx_len,
1137                           secctx);
1138         security_release_secctx(secctx, secctx_len);
1139         if (ret_val != 0)
1140                 goto list_cb_failure;
1141
1142         cb_arg->seq++;
1143         genlmsg_end(cb_arg->skb, data);
1144         return 0;
1145
1146 list_cb_failure:
1147         genlmsg_cancel(cb_arg->skb, data);
1148         return ret_val;
1149 }
1150
1151 /**
1152  * netlbl_unlabel_staticlist - Handle a STATICLIST message
1153  * @skb: the NETLINK buffer
1154  * @cb: the NETLINK callback
1155  *
1156  * Description:
1157  * Process a user generated STATICLIST message and dump the unlabeled
1158  * connection hash table in a form suitable for use in a kernel generated
1159  * STATICLIST message.  Returns the length of @skb.
1160  *
1161  */
1162 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1163                                      struct netlink_callback *cb)
1164 {
1165         struct netlbl_unlhsh_walk_arg cb_arg;
1166         u32 skip_bkt = cb->args[0];
1167         u32 skip_chain = cb->args[1];
1168         u32 iter_bkt;
1169         u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1170         struct netlbl_unlhsh_iface *iface;
1171         struct list_head *iter_list;
1172         struct netlbl_af4list *addr4;
1173 #if IS_ENABLED(CONFIG_IPV6)
1174         struct netlbl_af6list *addr6;
1175 #endif
1176
1177         cb_arg.nl_cb = cb;
1178         cb_arg.skb = skb;
1179         cb_arg.seq = cb->nlh->nlmsg_seq;
1180
1181         rcu_read_lock();
1182         for (iter_bkt = skip_bkt;
1183              iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1184              iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1185                 iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1186                 list_for_each_entry_rcu(iface, iter_list, list) {
1187                         if (!iface->valid ||
1188                             iter_chain++ < skip_chain)
1189                                 continue;
1190                         netlbl_af4list_foreach_rcu(addr4,
1191                                                    &iface->addr4_list) {
1192                                 if (iter_addr4++ < cb->args[2])
1193                                         continue;
1194                                 if (netlbl_unlabel_staticlist_gen(
1195                                               NLBL_UNLABEL_C_STATICLIST,
1196                                               iface,
1197                                               netlbl_unlhsh_addr4_entry(addr4),
1198                                               NULL,
1199                                               &cb_arg) < 0) {
1200                                         iter_addr4--;
1201                                         iter_chain--;
1202                                         goto unlabel_staticlist_return;
1203                                 }
1204                         }
1205 #if IS_ENABLED(CONFIG_IPV6)
1206                         netlbl_af6list_foreach_rcu(addr6,
1207                                                    &iface->addr6_list) {
1208                                 if (iter_addr6++ < cb->args[3])
1209                                         continue;
1210                                 if (netlbl_unlabel_staticlist_gen(
1211                                               NLBL_UNLABEL_C_STATICLIST,
1212                                               iface,
1213                                               NULL,
1214                                               netlbl_unlhsh_addr6_entry(addr6),
1215                                               &cb_arg) < 0) {
1216                                         iter_addr6--;
1217                                         iter_chain--;
1218                                         goto unlabel_staticlist_return;
1219                                 }
1220                         }
1221 #endif /* IPv6 */
1222                 }
1223         }
1224
1225 unlabel_staticlist_return:
1226         rcu_read_unlock();
1227         cb->args[0] = iter_bkt;
1228         cb->args[1] = iter_chain;
1229         cb->args[2] = iter_addr4;
1230         cb->args[3] = iter_addr6;
1231         return skb->len;
1232 }
1233
1234 /**
1235  * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1236  * @skb: the NETLINK buffer
1237  * @cb: the NETLINK callback
1238  *
1239  * Description:
1240  * Process a user generated STATICLISTDEF message and dump the default
1241  * unlabeled connection entry in a form suitable for use in a kernel generated
1242  * STATICLISTDEF message.  Returns the length of @skb.
1243  *
1244  */
1245 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1246                                         struct netlink_callback *cb)
1247 {
1248         struct netlbl_unlhsh_walk_arg cb_arg;
1249         struct netlbl_unlhsh_iface *iface;
1250         u32 iter_addr4 = 0, iter_addr6 = 0;
1251         struct netlbl_af4list *addr4;
1252 #if IS_ENABLED(CONFIG_IPV6)
1253         struct netlbl_af6list *addr6;
1254 #endif
1255
1256         cb_arg.nl_cb = cb;
1257         cb_arg.skb = skb;
1258         cb_arg.seq = cb->nlh->nlmsg_seq;
1259
1260         rcu_read_lock();
1261         iface = rcu_dereference(netlbl_unlhsh_def);
1262         if (iface == NULL || !iface->valid)
1263                 goto unlabel_staticlistdef_return;
1264
1265         netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1266                 if (iter_addr4++ < cb->args[0])
1267                         continue;
1268                 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1269                                               iface,
1270                                               netlbl_unlhsh_addr4_entry(addr4),
1271                                               NULL,
1272                                               &cb_arg) < 0) {
1273                         iter_addr4--;
1274                         goto unlabel_staticlistdef_return;
1275                 }
1276         }
1277 #if IS_ENABLED(CONFIG_IPV6)
1278         netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1279                 if (iter_addr6++ < cb->args[1])
1280                         continue;
1281                 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1282                                               iface,
1283                                               NULL,
1284                                               netlbl_unlhsh_addr6_entry(addr6),
1285                                               &cb_arg) < 0) {
1286                         iter_addr6--;
1287                         goto unlabel_staticlistdef_return;
1288                 }
1289         }
1290 #endif /* IPv6 */
1291
1292 unlabel_staticlistdef_return:
1293         rcu_read_unlock();
1294         cb->args[0] = iter_addr4;
1295         cb->args[1] = iter_addr6;
1296         return skb->len;
1297 }
1298
1299 /*
1300  * NetLabel Generic NETLINK Command Definitions
1301  */
1302
1303 static const struct genl_ops netlbl_unlabel_genl_ops[] = {
1304         {
1305         .cmd = NLBL_UNLABEL_C_STATICADD,
1306         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1307         .flags = GENL_ADMIN_PERM,
1308         .doit = netlbl_unlabel_staticadd,
1309         .dumpit = NULL,
1310         },
1311         {
1312         .cmd = NLBL_UNLABEL_C_STATICREMOVE,
1313         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1314         .flags = GENL_ADMIN_PERM,
1315         .doit = netlbl_unlabel_staticremove,
1316         .dumpit = NULL,
1317         },
1318         {
1319         .cmd = NLBL_UNLABEL_C_STATICLIST,
1320         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1321         .flags = 0,
1322         .doit = NULL,
1323         .dumpit = netlbl_unlabel_staticlist,
1324         },
1325         {
1326         .cmd = NLBL_UNLABEL_C_STATICADDDEF,
1327         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1328         .flags = GENL_ADMIN_PERM,
1329         .doit = netlbl_unlabel_staticadddef,
1330         .dumpit = NULL,
1331         },
1332         {
1333         .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1334         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1335         .flags = GENL_ADMIN_PERM,
1336         .doit = netlbl_unlabel_staticremovedef,
1337         .dumpit = NULL,
1338         },
1339         {
1340         .cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1341         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1342         .flags = 0,
1343         .doit = NULL,
1344         .dumpit = netlbl_unlabel_staticlistdef,
1345         },
1346         {
1347         .cmd = NLBL_UNLABEL_C_ACCEPT,
1348         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1349         .flags = GENL_ADMIN_PERM,
1350         .doit = netlbl_unlabel_accept,
1351         .dumpit = NULL,
1352         },
1353         {
1354         .cmd = NLBL_UNLABEL_C_LIST,
1355         .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1356         .flags = 0,
1357         .doit = netlbl_unlabel_list,
1358         .dumpit = NULL,
1359         },
1360 };
1361
1362 static struct genl_family netlbl_unlabel_gnl_family __ro_after_init = {
1363         .hdrsize = 0,
1364         .name = NETLBL_NLTYPE_UNLABELED_NAME,
1365         .version = NETLBL_PROTO_VERSION,
1366         .maxattr = NLBL_UNLABEL_A_MAX,
1367         .policy = netlbl_unlabel_genl_policy,
1368         .module = THIS_MODULE,
1369         .ops = netlbl_unlabel_genl_ops,
1370         .n_ops = ARRAY_SIZE(netlbl_unlabel_genl_ops),
1371 };
1372
1373 /*
1374  * NetLabel Generic NETLINK Protocol Functions
1375  */
1376
1377 /**
1378  * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
1379  *
1380  * Description:
1381  * Register the unlabeled packet NetLabel component with the Generic NETLINK
1382  * mechanism.  Returns zero on success, negative values on failure.
1383  *
1384  */
1385 int __init netlbl_unlabel_genl_init(void)
1386 {
1387         return genl_register_family(&netlbl_unlabel_gnl_family);
1388 }
1389
1390 /*
1391  * NetLabel KAPI Hooks
1392  */
1393
1394 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1395         .notifier_call = netlbl_unlhsh_netdev_handler,
1396 };
1397
1398 /**
1399  * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1400  * @size: the number of bits to use for the hash buckets
1401  *
1402  * Description:
1403  * Initializes the unlabeled connection hash table and registers a network
1404  * device notification handler.  This function should only be called by the
1405  * NetLabel subsystem itself during initialization.  Returns zero on success,
1406  * non-zero values on error.
1407  *
1408  */
1409 int __init netlbl_unlabel_init(u32 size)
1410 {
1411         u32 iter;
1412         struct netlbl_unlhsh_tbl *hsh_tbl;
1413
1414         if (size == 0)
1415                 return -EINVAL;
1416
1417         hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1418         if (hsh_tbl == NULL)
1419                 return -ENOMEM;
1420         hsh_tbl->size = 1 << size;
1421         hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1422                                sizeof(struct list_head),
1423                                GFP_KERNEL);
1424         if (hsh_tbl->tbl == NULL) {
1425                 kfree(hsh_tbl);
1426                 return -ENOMEM;
1427         }
1428         for (iter = 0; iter < hsh_tbl->size; iter++)
1429                 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1430
1431         spin_lock(&netlbl_unlhsh_lock);
1432         rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1433         spin_unlock(&netlbl_unlhsh_lock);
1434
1435         register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1436
1437         return 0;
1438 }
1439
1440 /**
1441  * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1442  * @skb: the packet
1443  * @family: protocol family
1444  * @secattr: the security attributes
1445  *
1446  * Description:
1447  * Determine the security attributes, if any, for an unlabled packet and return
1448  * them in @secattr.  Returns zero on success and negative values on failure.
1449  *
1450  */
1451 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1452                            u16 family,
1453                            struct netlbl_lsm_secattr *secattr)
1454 {
1455         struct netlbl_unlhsh_iface *iface;
1456
1457         rcu_read_lock();
1458         iface = netlbl_unlhsh_search_iface(skb->skb_iif);
1459         if (iface == NULL)
1460                 iface = rcu_dereference(netlbl_unlhsh_def);
1461         if (iface == NULL || !iface->valid)
1462                 goto unlabel_getattr_nolabel;
1463
1464 #if IS_ENABLED(CONFIG_IPV6)
1465         /* When resolving a fallback label, check the sk_buff version as
1466          * it is possible (e.g. SCTP) to have family = PF_INET6 while
1467          * receiving ip_hdr(skb)->version = 4.
1468          */
1469         if (family == PF_INET6 && ip_hdr(skb)->version == 4)
1470                 family = PF_INET;
1471 #endif /* IPv6 */
1472
1473         switch (family) {
1474         case PF_INET: {
1475                 struct iphdr *hdr4;
1476                 struct netlbl_af4list *addr4;
1477
1478                 hdr4 = ip_hdr(skb);
1479                 addr4 = netlbl_af4list_search(hdr4->saddr,
1480                                               &iface->addr4_list);
1481                 if (addr4 == NULL)
1482                         goto unlabel_getattr_nolabel;
1483                 secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1484                 break;
1485         }
1486 #if IS_ENABLED(CONFIG_IPV6)
1487         case PF_INET6: {
1488                 struct ipv6hdr *hdr6;
1489                 struct netlbl_af6list *addr6;
1490
1491                 hdr6 = ipv6_hdr(skb);
1492                 addr6 = netlbl_af6list_search(&hdr6->saddr,
1493                                               &iface->addr6_list);
1494                 if (addr6 == NULL)
1495                         goto unlabel_getattr_nolabel;
1496                 secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1497                 break;
1498         }
1499 #endif /* IPv6 */
1500         default:
1501                 goto unlabel_getattr_nolabel;
1502         }
1503         rcu_read_unlock();
1504
1505         secattr->flags |= NETLBL_SECATTR_SECID;
1506         secattr->type = NETLBL_NLTYPE_UNLABELED;
1507         return 0;
1508
1509 unlabel_getattr_nolabel:
1510         rcu_read_unlock();
1511         if (netlabel_unlabel_acceptflg == 0)
1512                 return -ENOMSG;
1513         secattr->type = NETLBL_NLTYPE_UNLABELED;
1514         return 0;
1515 }
1516
1517 /**
1518  * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1519  *
1520  * Description:
1521  * Set the default NetLabel configuration to allow incoming unlabeled packets
1522  * and to send unlabeled network traffic by default.
1523  *
1524  */
1525 int __init netlbl_unlabel_defconf(void)
1526 {
1527         int ret_val;
1528         struct netlbl_dom_map *entry;
1529         struct netlbl_audit audit_info;
1530
1531         /* Only the kernel is allowed to call this function and the only time
1532          * it is called is at bootup before the audit subsystem is reporting
1533          * messages so don't worry to much about these values. */
1534         security_task_getsecid(current, &audit_info.secid);
1535         audit_info.loginuid = GLOBAL_ROOT_UID;
1536         audit_info.sessionid = 0;
1537
1538         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1539         if (entry == NULL)
1540                 return -ENOMEM;
1541         entry->family = AF_UNSPEC;
1542         entry->def.type = NETLBL_NLTYPE_UNLABELED;
1543         ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1544         if (ret_val != 0)
1545                 return ret_val;
1546
1547         netlbl_unlabel_acceptflg_set(1, &audit_info);
1548
1549         return 0;
1550 }