net/netlabel/netlabel_unlabeled.c

   1 /*
   2  * NetLabel Unlabeled Support
   3  *
   4  * This file defines functions for dealing with unlabeled packets for the
   5  * NetLabel system.  The NetLabel system manages static and dynamic label
   6  * mappings for network protocols such as CIPSO and RIPSO.
   7  *
   8  * Author: Paul Moore <paul@paul-moore.com>
   9  *
  10  */
  11
  12 /*
  13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 - 2008
  14  *
  15  * This program is free software;  you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or
  18  * (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  23  * the GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program;  if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  28  *
  29  */
  30
  31 #include <linux/types.h>
  32 #include <linux/rcupdate.h>
  33 #include <linux/list.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/socket.h>
  36 #include <linux/string.h>
  37 #include <linux/skbuff.h>
  38 #include <linux/audit.h>
  39 #include <linux/in.h>
  40 #include <linux/in6.h>
  41 #include <linux/ip.h>
  42 #include <linux/ipv6.h>
  43 #include <linux/notifier.h>
  44 #include <linux/netdevice.h>
  45 #include <linux/security.h>
  46 #include <linux/slab.h>
  47 #include <net/sock.h>
  48 #include <net/netlink.h>
  49 #include <net/genetlink.h>
  50 #include <net/ip.h>
  51 #include <net/ipv6.h>
  52 #include <net/net_namespace.h>
  53 #include <net/netlabel.h>
  54 #include <asm/bug.h>
  55 #include <linux/atomic.h>
  56
  57 #include "netlabel_user.h"
  58 #include "netlabel_addrlist.h"
  59 #include "netlabel_domainhash.h"
  60 #include "netlabel_unlabeled.h"
  61 #include "netlabel_mgmt.h"
  62
  63 /* NOTE: at present we always use init's network namespace since we don't
  64  *       presently support different namespaces even though the majority of
  65  *       the functions in this file are "namespace safe" */
  66
  67 /* The unlabeled connection hash table which we use to map network interfaces
  68  * and addresses of unlabeled packets to a user specified secid value for the
  69  * LSM.  The hash table is used to lookup the network interface entry
  70  * (struct netlbl_unlhsh_iface) and then the interface entry is used to
  71  * lookup an IP address match from an ordered list.  If a network interface
  72  * match can not be found in the hash table then the default entry
  73  * (netlbl_unlhsh_def) is used.  The IP address entry list
  74  * (struct netlbl_unlhsh_addr) is ordered such that the entries with a
  75  * larger netmask come first.
  76  */
  77 struct netlbl_unlhsh_tbl {
  78         struct list_head *tbl;
  79         u32 size;
  80 };
  81 #define netlbl_unlhsh_addr4_entry(iter) \
  82         container_of(iter, struct netlbl_unlhsh_addr4, list)
  83 struct netlbl_unlhsh_addr4 {
  84         u32 secid;
  85
  86         struct netlbl_af4list list;
  87         struct rcu_head rcu;
  88 };
  89 #define netlbl_unlhsh_addr6_entry(iter) \
  90         container_of(iter, struct netlbl_unlhsh_addr6, list)
  91 struct netlbl_unlhsh_addr6 {
  92         u32 secid;
  93
  94         struct netlbl_af6list list;
  95         struct rcu_head rcu;
  96 };
  97 struct netlbl_unlhsh_iface {
  98         int ifindex;
  99         struct list_head addr4_list;
 100         struct list_head addr6_list;
 101
 102         u32 valid;
 103         struct list_head list;
 104         struct rcu_head rcu;
 105 };
 106
 107 /* Argument struct for netlbl_unlhsh_walk() */
 108 struct netlbl_unlhsh_walk_arg {
 109         struct netlink_callback *nl_cb;
 110         struct sk_buff *skb;
 111         u32 seq;
 112 };
 113
 114 /* Unlabeled connection hash table */
 115 /* updates should be so rare that having one spinlock for the entire
 116  * hash table should be okay */
 117 static DEFINE_SPINLOCK(netlbl_unlhsh_lock);
 118 #define netlbl_unlhsh_rcu_deref(p) \
 119         rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock))
 120 static struct netlbl_unlhsh_tbl *netlbl_unlhsh = NULL;
 121 static struct netlbl_unlhsh_iface *netlbl_unlhsh_def = NULL;
 122
 123 /* Accept unlabeled packets flag */
 124 static u8 netlabel_unlabel_acceptflg = 0;
 125
 126 /* NetLabel Generic NETLINK unlabeled family */
 127 static struct genl_family netlbl_unlabel_gnl_family = {
 128         .id = GENL_ID_GENERATE,
 129         .hdrsize = 0,
 130         .name = NETLBL_NLTYPE_UNLABELED_NAME,
 131         .version = NETLBL_PROTO_VERSION,
 132         .maxattr = NLBL_UNLABEL_A_MAX,
 133 };
 134
 135 /* NetLabel Netlink attribute policy */
 136 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
 137         [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
 138         [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
 139                                       .len = sizeof(struct in6_addr) },
 140         [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
 141                                       .len = sizeof(struct in6_addr) },
 142         [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
 143                                       .len = sizeof(struct in_addr) },
 144         [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
 145                                       .len = sizeof(struct in_addr) },
 146         [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
 147                                    .len = IFNAMSIZ - 1 },
 148         [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
 149 };
 150
 151 /*
 152  * Unlabeled Connection Hash Table Functions
 153  */
 154
 155 /**
 156  * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
 157  * @entry: the entry's RCU field
 158  *
 159  * Description:
 160  * This function is designed to be used as a callback to the call_rcu()
 161  * function so that memory allocated to a hash table interface entry can be
 162  * released safely.  It is important to note that this function does not free
 163  * the IPv4 and IPv6 address lists contained as part of an interface entry.  It
 164  * is up to the rest of the code to make sure an interface entry is only freed
 165  * once it's address lists are empty.
 166  *
 167  */
 168 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
 169 {
 170         struct netlbl_unlhsh_iface *iface;
 171         struct netlbl_af4list *iter4;
 172         struct netlbl_af4list *tmp4;
 173 #if IS_ENABLED(CONFIG_IPV6)
 174         struct netlbl_af6list *iter6;
 175         struct netlbl_af6list *tmp6;
 176 #endif /* IPv6 */
 177
 178         iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
 179
 180         /* no need for locks here since we are the only one with access to this
 181          * structure */
 182
 183         netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
 184                 netlbl_af4list_remove_entry(iter4);
 185                 kfree(netlbl_unlhsh_addr4_entry(iter4));
 186         }
 187 #if IS_ENABLED(CONFIG_IPV6)
 188         netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
 189                 netlbl_af6list_remove_entry(iter6);
 190                 kfree(netlbl_unlhsh_addr6_entry(iter6));
 191         }
 192 #endif /* IPv6 */
 193         kfree(iface);
 194 }
 195
 196 /**
 197  * netlbl_unlhsh_hash - Hashing function for the hash table
 198  * @ifindex: the network interface/device to hash
 199  *
 200  * Description:
 201  * This is the hashing function for the unlabeled hash table, it returns the
 202  * bucket number for the given device/interface.  The caller is responsible for
 203  * ensuring that the hash table is protected with either a RCU read lock or
 204  * the hash table lock.
 205  *
 206  */
 207 static u32 netlbl_unlhsh_hash(int ifindex)
 208 {
 209         return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1);
 210 }
 211
 212 /**
 213  * netlbl_unlhsh_search_iface - Search for a matching interface entry
 214  * @ifindex: the network interface
 215  *
 216  * Description:
 217  * Searches the unlabeled connection hash table and returns a pointer to the
 218  * interface entry which matches @ifindex, otherwise NULL is returned.  The
 219  * caller is responsible for ensuring that the hash table is protected with
 220  * either a RCU read lock or the hash table lock.
 221  *
 222  */
 223 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
 224 {
 225         u32 bkt;
 226         struct list_head *bkt_list;
 227         struct netlbl_unlhsh_iface *iter;
 228
 229         bkt = netlbl_unlhsh_hash(ifindex);
 230         bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt];
 231         list_for_each_entry_rcu(iter, bkt_list, list)
 232                 if (iter->valid && iter->ifindex == ifindex)
 233                         return iter;
 234
 235         return NULL;
 236 }
 237
 238 /**
 239  * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
 240  * @iface: the associated interface entry
 241  * @addr: IPv4 address in network byte order
 242  * @mask: IPv4 address mask in network byte order
 243  * @secid: LSM secid value for entry
 244  *
 245  * Description:
 246  * Add a new address entry into the unlabeled connection hash table using the
 247  * interface entry specified by @iface.  On success zero is returned, otherwise
 248  * a negative value is returned.
 249  *
 250  */
 251 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
 252                                    const struct in_addr *addr,
 253                                    const struct in_addr *mask,
 254                                    u32 secid)
 255 {
 256         int ret_val;
 257         struct netlbl_unlhsh_addr4 *entry;
 258
 259         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 260         if (entry == NULL)
 261                 return -ENOMEM;
 262
 263         entry->list.addr = addr->s_addr & mask->s_addr;
 264         entry->list.mask = mask->s_addr;
 265         entry->list.valid = 1;
 266         entry->secid = secid;
 267
 268         spin_lock(&netlbl_unlhsh_lock);
 269         ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
 270         spin_unlock(&netlbl_unlhsh_lock);
 271
 272         if (ret_val != 0)
 273                 kfree(entry);
 274         return ret_val;
 275 }
 276
 277 #if IS_ENABLED(CONFIG_IPV6)
 278 /**
 279  * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
 280  * @iface: the associated interface entry
 281  * @addr: IPv6 address in network byte order
 282  * @mask: IPv6 address mask in network byte order
 283  * @secid: LSM secid value for entry
 284  *
 285  * Description:
 286  * Add a new address entry into the unlabeled connection hash table using the
 287  * interface entry specified by @iface.  On success zero is returned, otherwise
 288  * a negative value is returned.
 289  *
 290  */
 291 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
 292                                    const struct in6_addr *addr,
 293                                    const struct in6_addr *mask,
 294                                    u32 secid)
 295 {
 296         int ret_val;
 297         struct netlbl_unlhsh_addr6 *entry;
 298
 299         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 300         if (entry == NULL)
 301                 return -ENOMEM;
 302
 303         entry->list.addr = *addr;
 304         entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
 305         entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
 306         entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
 307         entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
 308         entry->list.mask = *mask;
 309         entry->list.valid = 1;
 310         entry->secid = secid;
 311
 312         spin_lock(&netlbl_unlhsh_lock);
 313         ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
 314         spin_unlock(&netlbl_unlhsh_lock);
 315
 316         if (ret_val != 0)
 317                 kfree(entry);
 318         return 0;
 319 }
 320 #endif /* IPv6 */
 321
 322 /**
 323  * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
 324  * @ifindex: network interface
 325  *
 326  * Description:
 327  * Add a new, empty, interface entry into the unlabeled connection hash table.
 328  * On success a pointer to the new interface entry is returned, on failure NULL
 329  * is returned.
 330  *
 331  */
 332 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
 333 {
 334         u32 bkt;
 335         struct netlbl_unlhsh_iface *iface;
 336
 337         iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
 338         if (iface == NULL)
 339                 return NULL;
 340
 341         iface->ifindex = ifindex;
 342         INIT_LIST_HEAD(&iface->addr4_list);
 343         INIT_LIST_HEAD(&iface->addr6_list);
 344         iface->valid = 1;
 345
 346         spin_lock(&netlbl_unlhsh_lock);
 347         if (ifindex > 0) {
 348                 bkt = netlbl_unlhsh_hash(ifindex);
 349                 if (netlbl_unlhsh_search_iface(ifindex) != NULL)
 350                         goto add_iface_failure;
 351                 list_add_tail_rcu(&iface->list,
 352                              &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]);
 353         } else {
 354                 INIT_LIST_HEAD(&iface->list);
 355                 if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL)
 356                         goto add_iface_failure;
 357                 rcu_assign_pointer(netlbl_unlhsh_def, iface);
 358         }
 359         spin_unlock(&netlbl_unlhsh_lock);
 360
 361         return iface;
 362
 363 add_iface_failure:
 364         spin_unlock(&netlbl_unlhsh_lock);
 365         kfree(iface);
 366         return NULL;
 367 }
 368
 369 /**
 370  * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
 371  * @net: network namespace
 372  * @dev_name: interface name
 373  * @addr: IP address in network byte order
 374  * @mask: address mask in network byte order
 375  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
 376  * @secid: LSM secid value for the entry
 377  * @audit_info: NetLabel audit information
 378  *
 379  * Description:
 380  * Adds a new entry to the unlabeled connection hash table.  Returns zero on
 381  * success, negative values on failure.
 382  *
 383  */
 384 int netlbl_unlhsh_add(struct net *net,
 385                       const char *dev_name,
 386                       const void *addr,
 387                       const void *mask,
 388                       u32 addr_len,
 389                       u32 secid,
 390                       struct netlbl_audit *audit_info)
 391 {
 392         int ret_val;
 393         int ifindex;
 394         struct net_device *dev;
 395         struct netlbl_unlhsh_iface *iface;
 396         struct audit_buffer *audit_buf = NULL;
 397         char *secctx = NULL;
 398         u32 secctx_len;
 399
 400         if (addr_len != sizeof(struct in_addr) &&
 401             addr_len != sizeof(struct in6_addr))
 402                 return -EINVAL;
 403
 404         rcu_read_lock();
 405         if (dev_name != NULL) {
 406                 dev = dev_get_by_name_rcu(net, dev_name);
 407                 if (dev == NULL) {
 408                         ret_val = -ENODEV;
 409                         goto unlhsh_add_return;
 410                 }
 411                 ifindex = dev->ifindex;
 412                 iface = netlbl_unlhsh_search_iface(ifindex);
 413         } else {
 414                 ifindex = 0;
 415                 iface = rcu_dereference(netlbl_unlhsh_def);
 416         }
 417         if (iface == NULL) {
 418                 iface = netlbl_unlhsh_add_iface(ifindex);
 419                 if (iface == NULL) {
 420                         ret_val = -ENOMEM;
 421                         goto unlhsh_add_return;
 422                 }
 423         }
 424         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
 425                                               audit_info);
 426         switch (addr_len) {
 427         case sizeof(struct in_addr): {
 428                 const struct in_addr *addr4 = addr;
 429                 const struct in_addr *mask4 = mask;
 430
 431                 ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
 432                 if (audit_buf != NULL)
 433                         netlbl_af4list_audit_addr(audit_buf, 1,
 434                                                   dev_name,
 435                                                   addr4->s_addr,
 436                                                   mask4->s_addr);
 437                 break;
 438         }
 439 #if IS_ENABLED(CONFIG_IPV6)
 440         case sizeof(struct in6_addr): {
 441                 const struct in6_addr *addr6 = addr;
 442                 const struct in6_addr *mask6 = mask;
 443
 444                 ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
 445                 if (audit_buf != NULL)
 446                         netlbl_af6list_audit_addr(audit_buf, 1,
 447                                                   dev_name,
 448                                                   addr6, mask6);
 449                 break;
 450         }
 451 #endif /* IPv6 */
 452         default:
 453                 ret_val = -EINVAL;
 454         }
 455         if (ret_val == 0)
 456                 atomic_inc(&netlabel_mgmt_protocount);
 457
 458 unlhsh_add_return:
 459         rcu_read_unlock();
 460         if (audit_buf != NULL) {
 461                 if (security_secid_to_secctx(secid,
 462                                              &secctx,
 463                                              &secctx_len) == 0) {
 464                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 465                         security_release_secctx(secctx, secctx_len);
 466                 }
 467                 audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
 468                 audit_log_end(audit_buf);
 469         }
 470         return ret_val;
 471 }
 472
 473 /**
 474  * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
 475  * @net: network namespace
 476  * @iface: interface entry
 477  * @addr: IP address
 478  * @mask: IP address mask
 479  * @audit_info: NetLabel audit information
 480  *
 481  * Description:
 482  * Remove an IP address entry from the unlabeled connection hash table.
 483  * Returns zero on success, negative values on failure.
 484  *
 485  */
 486 static int netlbl_unlhsh_remove_addr4(struct net *net,
 487                                       struct netlbl_unlhsh_iface *iface,
 488                                       const struct in_addr *addr,
 489                                       const struct in_addr *mask,
 490                                       struct netlbl_audit *audit_info)
 491 {
 492         struct netlbl_af4list *list_entry;
 493         struct netlbl_unlhsh_addr4 *entry;
 494         struct audit_buffer *audit_buf;
 495         struct net_device *dev;
 496         char *secctx;
 497         u32 secctx_len;
 498
 499         spin_lock(&netlbl_unlhsh_lock);
 500         list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
 501                                            &iface->addr4_list);
 502         spin_unlock(&netlbl_unlhsh_lock);
 503         if (list_entry != NULL)
 504                 entry = netlbl_unlhsh_addr4_entry(list_entry);
 505         else
 506                 entry = NULL;
 507
 508         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
 509                                               audit_info);
 510         if (audit_buf != NULL) {
 511                 dev = dev_get_by_index(net, iface->ifindex);
 512                 netlbl_af4list_audit_addr(audit_buf, 1,
 513                                           (dev != NULL ? dev->name : NULL),
 514                                           addr->s_addr, mask->s_addr);
 515                 if (dev != NULL)
 516                         dev_put(dev);
 517                 if (entry != NULL &&
 518                     security_secid_to_secctx(entry->secid,
 519                                              &secctx, &secctx_len) == 0) {
 520                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 521                         security_release_secctx(secctx, secctx_len);
 522                 }
 523                 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 524                 audit_log_end(audit_buf);
 525         }
 526
 527         if (entry == NULL)
 528                 return -ENOENT;
 529
 530         kfree_rcu(entry, rcu);
 531         return 0;
 532 }
 533
 534 #if IS_ENABLED(CONFIG_IPV6)
 535 /**
 536  * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
 537  * @net: network namespace
 538  * @iface: interface entry
 539  * @addr: IP address
 540  * @mask: IP address mask
 541  * @audit_info: NetLabel audit information
 542  *
 543  * Description:
 544  * Remove an IP address entry from the unlabeled connection hash table.
 545  * Returns zero on success, negative values on failure.
 546  *
 547  */
 548 static int netlbl_unlhsh_remove_addr6(struct net *net,
 549                                       struct netlbl_unlhsh_iface *iface,
 550                                       const struct in6_addr *addr,
 551                                       const struct in6_addr *mask,
 552                                       struct netlbl_audit *audit_info)
 553 {
 554         struct netlbl_af6list *list_entry;
 555         struct netlbl_unlhsh_addr6 *entry;
 556         struct audit_buffer *audit_buf;
 557         struct net_device *dev;
 558         char *secctx;
 559         u32 secctx_len;
 560
 561         spin_lock(&netlbl_unlhsh_lock);
 562         list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
 563         spin_unlock(&netlbl_unlhsh_lock);
 564         if (list_entry != NULL)
 565                 entry = netlbl_unlhsh_addr6_entry(list_entry);
 566         else
 567                 entry = NULL;
 568
 569         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
 570                                               audit_info);
 571         if (audit_buf != NULL) {
 572                 dev = dev_get_by_index(net, iface->ifindex);
 573                 netlbl_af6list_audit_addr(audit_buf, 1,
 574                                           (dev != NULL ? dev->name : NULL),
 575                                           addr, mask);
 576                 if (dev != NULL)
 577                         dev_put(dev);
 578                 if (entry != NULL &&
 579                     security_secid_to_secctx(entry->secid,
 580                                              &secctx, &secctx_len) == 0) {
 581                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 582                         security_release_secctx(secctx, secctx_len);
 583                 }
 584                 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 585                 audit_log_end(audit_buf);
 586         }
 587
 588         if (entry == NULL)
 589                 return -ENOENT;
 590
 591         kfree_rcu(entry, rcu);
 592         return 0;
 593 }
 594 #endif /* IPv6 */
 595
 596 /**
 597  * netlbl_unlhsh_condremove_iface - Remove an interface entry
 598  * @iface: the interface entry
 599  *
 600  * Description:
 601  * Remove an interface entry from the unlabeled connection hash table if it is
 602  * empty.  An interface entry is considered to be empty if there are no
 603  * address entries assigned to it.
 604  *
 605  */
 606 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
 607 {
 608         struct netlbl_af4list *iter4;
 609 #if IS_ENABLED(CONFIG_IPV6)
 610         struct netlbl_af6list *iter6;
 611 #endif /* IPv6 */
 612
 613         spin_lock(&netlbl_unlhsh_lock);
 614         netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
 615                 goto unlhsh_condremove_failure;
 616 #if IS_ENABLED(CONFIG_IPV6)
 617         netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
 618                 goto unlhsh_condremove_failure;
 619 #endif /* IPv6 */
 620         iface->valid = 0;
 621         if (iface->ifindex > 0)
 622                 list_del_rcu(&iface->list);
 623         else
 624                 RCU_INIT_POINTER(netlbl_unlhsh_def, NULL);
 625         spin_unlock(&netlbl_unlhsh_lock);
 626
 627         call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
 628         return;
 629
 630 unlhsh_condremove_failure:
 631         spin_unlock(&netlbl_unlhsh_lock);
 632 }
 633
 634 /**
 635  * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
 636  * @net: network namespace
 637  * @dev_name: interface name
 638  * @addr: IP address in network byte order
 639  * @mask: address mask in network byte order
 640  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
 641  * @audit_info: NetLabel audit information
 642  *
 643  * Description:
 644  * Removes and existing entry from the unlabeled connection hash table.
 645  * Returns zero on success, negative values on failure.
 646  *
 647  */
 648 int netlbl_unlhsh_remove(struct net *net,
 649                          const char *dev_name,
 650                          const void *addr,
 651                          const void *mask,
 652                          u32 addr_len,
 653                          struct netlbl_audit *audit_info)
 654 {
 655         int ret_val;
 656         struct net_device *dev;
 657         struct netlbl_unlhsh_iface *iface;
 658
 659         if (addr_len != sizeof(struct in_addr) &&
 660             addr_len != sizeof(struct in6_addr))
 661                 return -EINVAL;
 662
 663         rcu_read_lock();
 664         if (dev_name != NULL) {
 665                 dev = dev_get_by_name_rcu(net, dev_name);
 666                 if (dev == NULL) {
 667                         ret_val = -ENODEV;
 668                         goto unlhsh_remove_return;
 669                 }
 670                 iface = netlbl_unlhsh_search_iface(dev->ifindex);
 671         } else
 672                 iface = rcu_dereference(netlbl_unlhsh_def);
 673         if (iface == NULL) {
 674                 ret_val = -ENOENT;
 675                 goto unlhsh_remove_return;
 676         }
 677         switch (addr_len) {
 678         case sizeof(struct in_addr):
 679                 ret_val = netlbl_unlhsh_remove_addr4(net,
 680                                                      iface, addr, mask,
 681                                                      audit_info);
 682                 break;
 683 #if IS_ENABLED(CONFIG_IPV6)
 684         case sizeof(struct in6_addr):
 685                 ret_val = netlbl_unlhsh_remove_addr6(net,
 686                                                      iface, addr, mask,
 687                                                      audit_info);
 688                 break;
 689 #endif /* IPv6 */
 690         default:
 691                 ret_val = -EINVAL;
 692         }
 693         if (ret_val == 0) {
 694                 netlbl_unlhsh_condremove_iface(iface);
 695                 atomic_dec(&netlabel_mgmt_protocount);
 696         }
 697
 698 unlhsh_remove_return:
 699         rcu_read_unlock();
 700         return ret_val;
 701 }
 702
 703 /*
 704  * General Helper Functions
 705  */
 706
 707 /**
 708  * netlbl_unlhsh_netdev_handler - Network device notification handler
 709  * @this: notifier block
 710  * @event: the event
 711  * @ptr: the netdevice notifier info (cast to void)
 712  *
 713  * Description:
 714  * Handle network device events, although at present all we care about is a
 715  * network device going away.  In the case of a device going away we clear any
 716  * related entries from the unlabeled connection hash table.
 717  *
 718  */
 719 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
 720                                         unsigned long event, void *ptr)
 721 {
 722         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 723         struct netlbl_unlhsh_iface *iface = NULL;
 724
 725         if (!net_eq(dev_net(dev), &init_net))
 726                 return NOTIFY_DONE;
 727
 728         /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
 729         if (event == NETDEV_DOWN) {
 730                 spin_lock(&netlbl_unlhsh_lock);
 731                 iface = netlbl_unlhsh_search_iface(dev->ifindex);
 732                 if (iface != NULL && iface->valid) {
 733                         iface->valid = 0;
 734                         list_del_rcu(&iface->list);
 735                 } else
 736                         iface = NULL;
 737                 spin_unlock(&netlbl_unlhsh_lock);
 738         }
 739
 740         if (iface != NULL)
 741                 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
 742
 743         return NOTIFY_DONE;
 744 }
 745
 746 /**
 747  * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
 748  * @value: desired value
 749  * @audit_info: NetLabel audit information
 750  *
 751  * Description:
 752  * Set the value of the unlabeled accept flag to @value.
 753  *
 754  */
 755 static void netlbl_unlabel_acceptflg_set(u8 value,
 756                                          struct netlbl_audit *audit_info)
 757 {
 758         struct audit_buffer *audit_buf;
 759         u8 old_val;
 760
 761         old_val = netlabel_unlabel_acceptflg;
 762         netlabel_unlabel_acceptflg = value;
 763         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
 764                                               audit_info);
 765         if (audit_buf != NULL) {
 766                 audit_log_format(audit_buf,
 767                                  " unlbl_accept=%u old=%u", value, old_val);
 768                 audit_log_end(audit_buf);
 769         }
 770 }
 771
 772 /**
 773  * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
 774  * @info: the Generic NETLINK info block
 775  * @addr: the IP address
 776  * @mask: the IP address mask
 777  * @len: the address length
 778  *
 779  * Description:
 780  * Examine the Generic NETLINK message and extract the IP address information.
 781  * Returns zero on success, negative values on failure.
 782  *
 783  */
 784 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
 785                                        void **addr,
 786                                        void **mask,
 787                                        u32 *len)
 788 {
 789         u32 addr_len;
 790
 791         if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR]) {
 792                 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
 793                 if (addr_len != sizeof(struct in_addr) &&
 794                     addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
 795                         return -EINVAL;
 796                 *len = addr_len;
 797                 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
 798                 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
 799                 return 0;
 800         } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
 801                 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
 802                 if (addr_len != sizeof(struct in6_addr) &&
 803                     addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
 804                         return -EINVAL;
 805                 *len = addr_len;
 806                 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
 807                 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
 808                 return 0;
 809         }
 810
 811         return -EINVAL;
 812 }
 813
 814 /*
 815  * NetLabel Command Handlers
 816  */
 817
 818 /**
 819  * netlbl_unlabel_accept - Handle an ACCEPT message
 820  * @skb: the NETLINK buffer
 821  * @info: the Generic NETLINK info block
 822  *
 823  * Description:
 824  * Process a user generated ACCEPT message and set the accept flag accordingly.
 825  * Returns zero on success, negative values on failure.
 826  *
 827  */
 828 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
 829 {
 830         u8 value;
 831         struct netlbl_audit audit_info;
 832
 833         if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
 834                 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
 835                 if (value == 1 || value == 0) {
 836                         netlbl_netlink_auditinfo(skb, &audit_info);
 837                         netlbl_unlabel_acceptflg_set(value, &audit_info);
 838                         return 0;
 839                 }
 840         }
 841
 842         return -EINVAL;
 843 }
 844
 845 /**
 846  * netlbl_unlabel_list - Handle a LIST message
 847  * @skb: the NETLINK buffer
 848  * @info: the Generic NETLINK info block
 849  *
 850  * Description:
 851  * Process a user generated LIST message and respond with the current status.
 852  * Returns zero on success, negative values on failure.
 853  *
 854  */
 855 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
 856 {
 857         int ret_val = -EINVAL;
 858         struct sk_buff *ans_skb;
 859         void *data;
 860
 861         ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 862         if (ans_skb == NULL)
 863                 goto list_failure;
 864         data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
 865                                  0, NLBL_UNLABEL_C_LIST);
 866         if (data == NULL) {
 867                 ret_val = -ENOMEM;
 868                 goto list_failure;
 869         }
 870
 871         ret_val = nla_put_u8(ans_skb,
 872                              NLBL_UNLABEL_A_ACPTFLG,
 873                              netlabel_unlabel_acceptflg);
 874         if (ret_val != 0)
 875                 goto list_failure;
 876
 877         genlmsg_end(ans_skb, data);
 878         return genlmsg_reply(ans_skb, info);
 879
 880 list_failure:
 881         kfree_skb(ans_skb);
 882         return ret_val;
 883 }
 884
 885 /**
 886  * netlbl_unlabel_staticadd - Handle a STATICADD message
 887  * @skb: the NETLINK buffer
 888  * @info: the Generic NETLINK info block
 889  *
 890  * Description:
 891  * Process a user generated STATICADD message and add a new unlabeled
 892  * connection entry to the hash table.  Returns zero on success, negative
 893  * values on failure.
 894  *
 895  */
 896 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
 897                                     struct genl_info *info)
 898 {
 899         int ret_val;
 900         char *dev_name;
 901         void *addr;
 902         void *mask;
 903         u32 addr_len;
 904         u32 secid;
 905         struct netlbl_audit audit_info;
 906
 907         /* Don't allow users to add both IPv4 and IPv6 addresses for a
 908          * single entry.  However, allow users to create two entries, one each
 909          * for IPv4 and IPv4, with the same LSM security context which should
 910          * achieve the same result. */
 911         if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
 912             !info->attrs[NLBL_UNLABEL_A_IFACE] ||
 913             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 914                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 915               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 916                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 917                 return -EINVAL;
 918
 919         netlbl_netlink_auditinfo(skb, &audit_info);
 920
 921         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 922         if (ret_val != 0)
 923                 return ret_val;
 924         dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
 925         ret_val = security_secctx_to_secid(
 926                                   nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 927                                   nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 928                                   &secid);
 929         if (ret_val != 0)
 930                 return ret_val;
 931
 932         return netlbl_unlhsh_add(&init_net,
 933                                  dev_name, addr, mask, addr_len, secid,
 934                                  &audit_info);
 935 }
 936
 937 /**
 938  * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
 939  * @skb: the NETLINK buffer
 940  * @info: the Generic NETLINK info block
 941  *
 942  * Description:
 943  * Process a user generated STATICADDDEF message and add a new default
 944  * unlabeled connection entry.  Returns zero on success, negative values on
 945  * failure.
 946  *
 947  */
 948 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
 949                                        struct genl_info *info)
 950 {
 951         int ret_val;
 952         void *addr;
 953         void *mask;
 954         u32 addr_len;
 955         u32 secid;
 956         struct netlbl_audit audit_info;
 957
 958         /* Don't allow users to add both IPv4 and IPv6 addresses for a
 959          * single entry.  However, allow users to create two entries, one each
 960          * for IPv4 and IPv6, with the same LSM security context which should
 961          * achieve the same result. */
 962         if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
 963             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 964                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 965               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 966                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 967                 return -EINVAL;
 968
 969         netlbl_netlink_auditinfo(skb, &audit_info);
 970
 971         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 972         if (ret_val != 0)
 973                 return ret_val;
 974         ret_val = security_secctx_to_secid(
 975                                   nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 976                                   nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 977                                   &secid);
 978         if (ret_val != 0)
 979                 return ret_val;
 980
 981         return netlbl_unlhsh_add(&init_net,
 982                                  NULL, addr, mask, addr_len, secid,
 983                                  &audit_info);
 984 }
 985
 986 /**
 987  * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
 988  * @skb: the NETLINK buffer
 989  * @info: the Generic NETLINK info block
 990  *
 991  * Description:
 992  * Process a user generated STATICREMOVE message and remove the specified
 993  * unlabeled connection entry.  Returns zero on success, negative values on
 994  * failure.
 995  *
 996  */
 997 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
 998                                        struct genl_info *info)
 999 {
1000         int ret_val;
1001         char *dev_name;
1002         void *addr;
1003         void *mask;
1004         u32 addr_len;
1005         struct netlbl_audit audit_info;
1006
1007         /* See the note in netlbl_unlabel_staticadd() about not allowing both
1008          * IPv4 and IPv6 in the same entry. */
1009         if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
1010             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1011                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1012               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1013                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1014                 return -EINVAL;
1015
1016         netlbl_netlink_auditinfo(skb, &audit_info);
1017
1018         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1019         if (ret_val != 0)
1020                 return ret_val;
1021         dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1022
1023         return netlbl_unlhsh_remove(&init_net,
1024                                     dev_name, addr, mask, addr_len,
1025                                     &audit_info);
1026 }
1027
1028 /**
1029  * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1030  * @skb: the NETLINK buffer
1031  * @info: the Generic NETLINK info block
1032  *
1033  * Description:
1034  * Process a user generated STATICREMOVEDEF message and remove the default
1035  * unlabeled connection entry.  Returns zero on success, negative values on
1036  * failure.
1037  *
1038  */
1039 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1040                                           struct genl_info *info)
1041 {
1042         int ret_val;
1043         void *addr;
1044         void *mask;
1045         u32 addr_len;
1046         struct netlbl_audit audit_info;
1047
1048         /* See the note in netlbl_unlabel_staticadd() about not allowing both
1049          * IPv4 and IPv6 in the same entry. */
1050         if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1051                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1052               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1053                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1054                 return -EINVAL;
1055
1056         netlbl_netlink_auditinfo(skb, &audit_info);
1057
1058         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1059         if (ret_val != 0)
1060                 return ret_val;
1061
1062         return netlbl_unlhsh_remove(&init_net,
1063                                     NULL, addr, mask, addr_len,
1064                                     &audit_info);
1065 }
1066
1067
1068 /**
1069  * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1070  * @cmd: command/message
1071  * @iface: the interface entry
1072  * @addr4: the IPv4 address entry
1073  * @addr6: the IPv6 address entry
1074  * @arg: the netlbl_unlhsh_walk_arg structure
1075  *
1076  * Description:
1077  * This function is designed to be used to generate a response for a
1078  * STATICLIST or STATICLISTDEF message.  When called either @addr4 or @addr6
1079  * can be specified, not both, the other unspecified entry should be set to
1080  * NULL by the caller.  Returns the size of the message on success, negative
1081  * values on failure.
1082  *
1083  */
1084 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1085                                        const struct netlbl_unlhsh_iface *iface,
1086                                        const struct netlbl_unlhsh_addr4 *addr4,
1087                                        const struct netlbl_unlhsh_addr6 *addr6,
1088                                        void *arg)
1089 {
1090         int ret_val = -ENOMEM;
1091         struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1092         struct net_device *dev;
1093         void *data;
1094         u32 secid;
1095         char *secctx;
1096         u32 secctx_len;
1097
1098         data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
1099                            cb_arg->seq, &netlbl_unlabel_gnl_family,
1100                            NLM_F_MULTI, cmd);
1101         if (data == NULL)
1102                 goto list_cb_failure;
1103
1104         if (iface->ifindex > 0) {
1105                 dev = dev_get_by_index(&init_net, iface->ifindex);
1106                 if (!dev) {
1107                         ret_val = -ENODEV;
1108                         goto list_cb_failure;
1109                 }
1110                 ret_val = nla_put_string(cb_arg->skb,
1111                                          NLBL_UNLABEL_A_IFACE, dev->name);
1112                 dev_put(dev);
1113                 if (ret_val != 0)
1114                         goto list_cb_failure;
1115         }
1116
1117         if (addr4) {
1118                 struct in_addr addr_struct;
1119
1120                 addr_struct.s_addr = addr4->list.addr;
1121                 ret_val = nla_put(cb_arg->skb,
1122                                   NLBL_UNLABEL_A_IPV4ADDR,
1123                                   sizeof(struct in_addr),
1124                                   &addr_struct);
1125                 if (ret_val != 0)
1126                         goto list_cb_failure;
1127
1128                 addr_struct.s_addr = addr4->list.mask;
1129                 ret_val = nla_put(cb_arg->skb,
1130                                   NLBL_UNLABEL_A_IPV4MASK,
1131                                   sizeof(struct in_addr),
1132                                   &addr_struct);
1133                 if (ret_val != 0)
1134                         goto list_cb_failure;
1135
1136                 secid = addr4->secid;
1137         } else {
1138                 ret_val = nla_put(cb_arg->skb,
1139                                   NLBL_UNLABEL_A_IPV6ADDR,
1140                                   sizeof(struct in6_addr),
1141                                   &addr6->list.addr);
1142                 if (ret_val != 0)
1143                         goto list_cb_failure;
1144
1145                 ret_val = nla_put(cb_arg->skb,
1146                                   NLBL_UNLABEL_A_IPV6MASK,
1147                                   sizeof(struct in6_addr),
1148                                   &addr6->list.mask);
1149                 if (ret_val != 0)
1150                         goto list_cb_failure;
1151
1152                 secid = addr6->secid;
1153         }
1154
1155         ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1156         if (ret_val != 0)
1157                 goto list_cb_failure;
1158         ret_val = nla_put(cb_arg->skb,
1159                           NLBL_UNLABEL_A_SECCTX,
1160                           secctx_len,
1161                           secctx);
1162         security_release_secctx(secctx, secctx_len);
1163         if (ret_val != 0)
1164                 goto list_cb_failure;
1165
1166         cb_arg->seq++;
1167         return genlmsg_end(cb_arg->skb, data);
1168
1169 list_cb_failure:
1170         genlmsg_cancel(cb_arg->skb, data);
1171         return ret_val;
1172 }
1173
1174 /**
1175  * netlbl_unlabel_staticlist - Handle a STATICLIST message
1176  * @skb: the NETLINK buffer
1177  * @cb: the NETLINK callback
1178  *
1179  * Description:
1180  * Process a user generated STATICLIST message and dump the unlabeled
1181  * connection hash table in a form suitable for use in a kernel generated
1182  * STATICLIST message.  Returns the length of @skb.
1183  *
1184  */
1185 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1186                                      struct netlink_callback *cb)
1187 {
1188         struct netlbl_unlhsh_walk_arg cb_arg;
1189         u32 skip_bkt = cb->args[0];
1190         u32 skip_chain = cb->args[1];
1191         u32 iter_bkt;
1192         u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1193         struct netlbl_unlhsh_iface *iface;
1194         struct list_head *iter_list;
1195         struct netlbl_af4list *addr4;
1196 #if IS_ENABLED(CONFIG_IPV6)
1197         struct netlbl_af6list *addr6;
1198 #endif
1199
1200         cb_arg.nl_cb = cb;
1201         cb_arg.skb = skb;
1202         cb_arg.seq = cb->nlh->nlmsg_seq;
1203
1204         rcu_read_lock();
1205         for (iter_bkt = skip_bkt;
1206              iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1207              iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1208                 iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1209                 list_for_each_entry_rcu(iface, iter_list, list) {
1210                         if (!iface->valid ||
1211                             iter_chain++ < skip_chain)
1212                                 continue;
1213                         netlbl_af4list_foreach_rcu(addr4,
1214                                                    &iface->addr4_list) {
1215                                 if (iter_addr4++ < cb->args[2])
1216                                         continue;
1217                                 if (netlbl_unlabel_staticlist_gen(
1218                                               NLBL_UNLABEL_C_STATICLIST,
1219                                               iface,
1220                                               netlbl_unlhsh_addr4_entry(addr4),
1221                                               NULL,
1222                                               &cb_arg) < 0) {
1223                                         iter_addr4--;
1224                                         iter_chain--;
1225                                         goto unlabel_staticlist_return;
1226                                 }
1227                         }
1228 #if IS_ENABLED(CONFIG_IPV6)
1229                         netlbl_af6list_foreach_rcu(addr6,
1230                                                    &iface->addr6_list) {
1231                                 if (iter_addr6++ < cb->args[3])
1232                                         continue;
1233                                 if (netlbl_unlabel_staticlist_gen(
1234                                               NLBL_UNLABEL_C_STATICLIST,
1235                                               iface,
1236                                               NULL,
1237                                               netlbl_unlhsh_addr6_entry(addr6),
1238                                               &cb_arg) < 0) {
1239                                         iter_addr6--;
1240                                         iter_chain--;
1241                                         goto unlabel_staticlist_return;
1242                                 }
1243                         }
1244 #endif /* IPv6 */
1245                 }
1246         }
1247
1248 unlabel_staticlist_return:
1249         rcu_read_unlock();
1250         cb->args[0] = iter_bkt;
1251         cb->args[1] = iter_chain;
1252         cb->args[2] = iter_addr4;
1253         cb->args[3] = iter_addr6;
1254         return skb->len;
1255 }
1256
1257 /**
1258  * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1259  * @skb: the NETLINK buffer
1260  * @cb: the NETLINK callback
1261  *
1262  * Description:
1263  * Process a user generated STATICLISTDEF message and dump the default
1264  * unlabeled connection entry in a form suitable for use in a kernel generated
1265  * STATICLISTDEF message.  Returns the length of @skb.
1266  *
1267  */
1268 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1269                                         struct netlink_callback *cb)
1270 {
1271         struct netlbl_unlhsh_walk_arg cb_arg;
1272         struct netlbl_unlhsh_iface *iface;
1273         u32 iter_addr4 = 0, iter_addr6 = 0;
1274         struct netlbl_af4list *addr4;
1275 #if IS_ENABLED(CONFIG_IPV6)
1276         struct netlbl_af6list *addr6;
1277 #endif
1278
1279         cb_arg.nl_cb = cb;
1280         cb_arg.skb = skb;
1281         cb_arg.seq = cb->nlh->nlmsg_seq;
1282
1283         rcu_read_lock();
1284         iface = rcu_dereference(netlbl_unlhsh_def);
1285         if (iface == NULL || !iface->valid)
1286                 goto unlabel_staticlistdef_return;
1287
1288         netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1289                 if (iter_addr4++ < cb->args[0])
1290                         continue;
1291                 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1292                                               iface,
1293                                               netlbl_unlhsh_addr4_entry(addr4),
1294                                               NULL,
1295                                               &cb_arg) < 0) {
1296                         iter_addr4--;
1297                         goto unlabel_staticlistdef_return;
1298                 }
1299         }
1300 #if IS_ENABLED(CONFIG_IPV6)
1301         netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1302                 if (iter_addr6++ < cb->args[1])
1303                         continue;
1304                 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1305                                               iface,
1306                                               NULL,
1307                                               netlbl_unlhsh_addr6_entry(addr6),
1308                                               &cb_arg) < 0) {
1309                         iter_addr6--;
1310                         goto unlabel_staticlistdef_return;
1311                 }
1312         }
1313 #endif /* IPv6 */
1314
1315 unlabel_staticlistdef_return:
1316         rcu_read_unlock();
1317         cb->args[0] = iter_addr4;
1318         cb->args[1] = iter_addr6;
1319         return skb->len;
1320 }
1321
1322 /*
1323  * NetLabel Generic NETLINK Command Definitions
1324  */
1325
1326 static struct genl_ops netlbl_unlabel_genl_ops[] = {
1327         {
1328         .cmd = NLBL_UNLABEL_C_STATICADD,
1329         .flags = GENL_ADMIN_PERM,
1330         .policy = netlbl_unlabel_genl_policy,
1331         .doit = netlbl_unlabel_staticadd,
1332         .dumpit = NULL,
1333         },
1334         {
1335         .cmd = NLBL_UNLABEL_C_STATICREMOVE,
1336         .flags = GENL_ADMIN_PERM,
1337         .policy = netlbl_unlabel_genl_policy,
1338         .doit = netlbl_unlabel_staticremove,
1339         .dumpit = NULL,
1340         },
1341         {
1342         .cmd = NLBL_UNLABEL_C_STATICLIST,
1343         .flags = 0,
1344         .policy = netlbl_unlabel_genl_policy,
1345         .doit = NULL,
1346         .dumpit = netlbl_unlabel_staticlist,
1347         },
1348         {
1349         .cmd = NLBL_UNLABEL_C_STATICADDDEF,
1350         .flags = GENL_ADMIN_PERM,
1351         .policy = netlbl_unlabel_genl_policy,
1352         .doit = netlbl_unlabel_staticadddef,
1353         .dumpit = NULL,
1354         },
1355         {
1356         .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1357         .flags = GENL_ADMIN_PERM,
1358         .policy = netlbl_unlabel_genl_policy,
1359         .doit = netlbl_unlabel_staticremovedef,
1360         .dumpit = NULL,
1361         },
1362         {
1363         .cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1364         .flags = 0,
1365         .policy = netlbl_unlabel_genl_policy,
1366         .doit = NULL,
1367         .dumpit = netlbl_unlabel_staticlistdef,
1368         },
1369         {
1370         .cmd = NLBL_UNLABEL_C_ACCEPT,
1371         .flags = GENL_ADMIN_PERM,
1372         .policy = netlbl_unlabel_genl_policy,
1373         .doit = netlbl_unlabel_accept,
1374         .dumpit = NULL,
1375         },
1376         {
1377         .cmd = NLBL_UNLABEL_C_LIST,
1378         .flags = 0,
1379         .policy = netlbl_unlabel_genl_policy,
1380         .doit = netlbl_unlabel_list,
1381         .dumpit = NULL,
1382         },
1383 };
1384
1385 /*
1386  * NetLabel Generic NETLINK Protocol Functions
1387  */
1388
1389 /**
1390  * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
1391  *
1392  * Description:
1393  * Register the unlabeled packet NetLabel component with the Generic NETLINK
1394  * mechanism.  Returns zero on success, negative values on failure.
1395  *
1396  */
1397 int __init netlbl_unlabel_genl_init(void)
1398 {
1399         return genl_register_family_with_ops(&netlbl_unlabel_gnl_family,
1400                 netlbl_unlabel_genl_ops, ARRAY_SIZE(netlbl_unlabel_genl_ops));
1401 }
1402
1403 /*
1404  * NetLabel KAPI Hooks
1405  */
1406
1407 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1408         .notifier_call = netlbl_unlhsh_netdev_handler,
1409 };
1410
1411 /**
1412  * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1413  * @size: the number of bits to use for the hash buckets
1414  *
1415  * Description:
1416  * Initializes the unlabeled connection hash table and registers a network
1417  * device notification handler.  This function should only be called by the
1418  * NetLabel subsystem itself during initialization.  Returns zero on success,
1419  * non-zero values on error.
1420  *
1421  */
1422 int __init netlbl_unlabel_init(u32 size)
1423 {
1424         u32 iter;
1425         struct netlbl_unlhsh_tbl *hsh_tbl;
1426
1427         if (size == 0)
1428                 return -EINVAL;
1429
1430         hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1431         if (hsh_tbl == NULL)
1432                 return -ENOMEM;
1433         hsh_tbl->size = 1 << size;
1434         hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1435                                sizeof(struct list_head),
1436                                GFP_KERNEL);
1437         if (hsh_tbl->tbl == NULL) {
1438                 kfree(hsh_tbl);
1439                 return -ENOMEM;
1440         }
1441         for (iter = 0; iter < hsh_tbl->size; iter++)
1442                 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1443
1444         spin_lock(&netlbl_unlhsh_lock);
1445         rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1446         spin_unlock(&netlbl_unlhsh_lock);
1447
1448         register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1449
1450         return 0;
1451 }
1452
1453 /**
1454  * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1455  * @skb: the packet
1456  * @family: protocol family
1457  * @secattr: the security attributes
1458  *
1459  * Description:
1460  * Determine the security attributes, if any, for an unlabled packet and return
1461  * them in @secattr.  Returns zero on success and negative values on failure.
1462  *
1463  */
1464 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1465                            u16 family,
1466                            struct netlbl_lsm_secattr *secattr)
1467 {
1468         struct netlbl_unlhsh_iface *iface;
1469
1470         rcu_read_lock();
1471         iface = netlbl_unlhsh_search_iface(skb->skb_iif);
1472         if (iface == NULL)
1473                 iface = rcu_dereference(netlbl_unlhsh_def);
1474         if (iface == NULL || !iface->valid)
1475                 goto unlabel_getattr_nolabel;
1476         switch (family) {
1477         case PF_INET: {
1478                 struct iphdr *hdr4;
1479                 struct netlbl_af4list *addr4;
1480
1481                 hdr4 = ip_hdr(skb);
1482                 addr4 = netlbl_af4list_search(hdr4->saddr,
1483                                               &iface->addr4_list);
1484                 if (addr4 == NULL)
1485                         goto unlabel_getattr_nolabel;
1486                 secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1487                 break;
1488         }
1489 #if IS_ENABLED(CONFIG_IPV6)
1490         case PF_INET6: {
1491                 struct ipv6hdr *hdr6;
1492                 struct netlbl_af6list *addr6;
1493
1494                 hdr6 = ipv6_hdr(skb);
1495                 addr6 = netlbl_af6list_search(&hdr6->saddr,
1496                                               &iface->addr6_list);
1497                 if (addr6 == NULL)
1498                         goto unlabel_getattr_nolabel;
1499                 secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1500                 break;
1501         }
1502 #endif /* IPv6 */
1503         default:
1504                 goto unlabel_getattr_nolabel;
1505         }
1506         rcu_read_unlock();
1507
1508         secattr->flags |= NETLBL_SECATTR_SECID;
1509         secattr->type = NETLBL_NLTYPE_UNLABELED;
1510         return 0;
1511
1512 unlabel_getattr_nolabel:
1513         rcu_read_unlock();
1514         if (netlabel_unlabel_acceptflg == 0)
1515                 return -ENOMSG;
1516         secattr->type = NETLBL_NLTYPE_UNLABELED;
1517         return 0;
1518 }
1519
1520 /**
1521  * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1522  *
1523  * Description:
1524  * Set the default NetLabel configuration to allow incoming unlabeled packets
1525  * and to send unlabeled network traffic by default.
1526  *
1527  */
1528 int __init netlbl_unlabel_defconf(void)
1529 {
1530         int ret_val;
1531         struct netlbl_dom_map *entry;
1532         struct netlbl_audit audit_info;
1533
1534         /* Only the kernel is allowed to call this function and the only time
1535          * it is called is at bootup before the audit subsystem is reporting
1536          * messages so don't worry to much about these values. */
1537         security_task_getsecid(current, &audit_info.secid);
1538         audit_info.loginuid = GLOBAL_ROOT_UID;
1539         audit_info.sessionid = 0;
1540
1541         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1542         if (entry == NULL)
1543                 return -ENOMEM;
1544         entry->def.type = NETLBL_NLTYPE_UNLABELED;
1545         ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1546         if (ret_val != 0)
1547                 return ret_val;
1548
1549         netlbl_unlabel_acceptflg_set(1, &audit_info);
1550
1551         return 0;
1552 }