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 <[email protected]>
   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, see <http://www.gnu.org/licenses/>.
  27  *
  28  */
  29
  30 #include <linux/types.h>
  31 #include <linux/rcupdate.h>
  32 #include <linux/list.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/socket.h>
  35 #include <linux/string.h>
  36 #include <linux/skbuff.h>
  37 #include <linux/audit.h>
  38 #include <linux/in.h>
  39 #include <linux/in6.h>
  40 #include <linux/ip.h>
  41 #include <linux/ipv6.h>
  42 #include <linux/notifier.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/security.h>
  45 #include <linux/slab.h>
  46 #include <net/sock.h>
  47 #include <net/netlink.h>
  48 #include <net/genetlink.h>
  49 #include <net/ip.h>
  50 #include <net/ipv6.h>
  51 #include <net/net_namespace.h>
  52 #include <net/netlabel.h>
  53 #include <asm/bug.h>
  54 #include <linux/atomic.h>
  55
  56 #include "netlabel_user.h"
  57 #include "netlabel_addrlist.h"
  58 #include "netlabel_domainhash.h"
  59 #include "netlabel_unlabeled.h"
  60 #include "netlabel_mgmt.h"
  61
  62 /* NOTE: at present we always use init's network namespace since we don't
  63  *       presently support different namespaces even though the majority of
  64  *       the functions in this file are "namespace safe" */
  65
  66 /* The unlabeled connection hash table which we use to map network interfaces
  67  * and addresses of unlabeled packets to a user specified secid value for the
  68  * LSM.  The hash table is used to lookup the network interface entry
  69  * (struct netlbl_unlhsh_iface) and then the interface entry is used to
  70  * lookup an IP address match from an ordered list.  If a network interface
  71  * match can not be found in the hash table then the default entry
  72  * (netlbl_unlhsh_def) is used.  The IP address entry list
  73  * (struct netlbl_unlhsh_addr) is ordered such that the entries with a
  74  * larger netmask come first.
  75  */
  76 struct netlbl_unlhsh_tbl {
  77         struct list_head *tbl;
  78         u32 size;
  79 };
  80 #define netlbl_unlhsh_addr4_entry(iter) \
  81         container_of(iter, struct netlbl_unlhsh_addr4, list)
  82 struct netlbl_unlhsh_addr4 {
  83         u32 secid;
  84
  85         struct netlbl_af4list list;
  86         struct rcu_head rcu;
  87 };
  88 #define netlbl_unlhsh_addr6_entry(iter) \
  89         container_of(iter, struct netlbl_unlhsh_addr6, list)
  90 struct netlbl_unlhsh_addr6 {
  91         u32 secid;
  92
  93         struct netlbl_af6list list;
  94         struct rcu_head rcu;
  95 };
  96 struct netlbl_unlhsh_iface {
  97         int ifindex;
  98         struct list_head addr4_list;
  99         struct list_head addr6_list;
 100
 101         u32 valid;
 102         struct list_head list;
 103         struct rcu_head rcu;
 104 };
 105
 106 /* Argument struct for netlbl_unlhsh_walk() */
 107 struct netlbl_unlhsh_walk_arg {
 108         struct netlink_callback *nl_cb;
 109         struct sk_buff *skb;
 110         u32 seq;
 111 };
 112
 113 /* Unlabeled connection hash table */
 114 /* updates should be so rare that having one spinlock for the entire
 115  * hash table should be okay */
 116 static DEFINE_SPINLOCK(netlbl_unlhsh_lock);
 117 #define netlbl_unlhsh_rcu_deref(p) \
 118         rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock))
 119 static struct netlbl_unlhsh_tbl __rcu *netlbl_unlhsh;
 120 static struct netlbl_unlhsh_iface __rcu *netlbl_unlhsh_def;
 121
 122 /* Accept unlabeled packets flag */
 123 static u8 netlabel_unlabel_acceptflg;
 124
 125 /* NetLabel Generic NETLINK unlabeled family */
 126 static struct genl_family netlbl_unlabel_gnl_family;
 127
 128 /* NetLabel Netlink attribute policy */
 129 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
 130         [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
 131         [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
 132                                       .len = sizeof(struct in6_addr) },
 133         [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
 134                                       .len = sizeof(struct in6_addr) },
 135         [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
 136                                       .len = sizeof(struct in_addr) },
 137         [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
 138                                       .len = sizeof(struct in_addr) },
 139         [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
 140                                    .len = IFNAMSIZ - 1 },
 141         [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
 142 };
 143
 144 /*
 145  * Unlabeled Connection Hash Table Functions
 146  */
 147
 148 /**
 149  * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
 150  * @entry: the entry's RCU field
 151  *
 152  * Description:
 153  * This function is designed to be used as a callback to the call_rcu()
 154  * function so that memory allocated to a hash table interface entry can be
 155  * released safely.  It is important to note that this function does not free
 156  * the IPv4 and IPv6 address lists contained as part of an interface entry.  It
 157  * is up to the rest of the code to make sure an interface entry is only freed
 158  * once it's address lists are empty.
 159  *
 160  */
 161 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
 162 {
 163         struct netlbl_unlhsh_iface *iface;
 164         struct netlbl_af4list *iter4;
 165         struct netlbl_af4list *tmp4;
 166 #if IS_ENABLED(CONFIG_IPV6)
 167         struct netlbl_af6list *iter6;
 168         struct netlbl_af6list *tmp6;
 169 #endif /* IPv6 */
 170
 171         iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
 172
 173         /* no need for locks here since we are the only one with access to this
 174          * structure */
 175
 176         netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
 177                 netlbl_af4list_remove_entry(iter4);
 178                 kfree(netlbl_unlhsh_addr4_entry(iter4));
 179         }
 180 #if IS_ENABLED(CONFIG_IPV6)
 181         netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
 182                 netlbl_af6list_remove_entry(iter6);
 183                 kfree(netlbl_unlhsh_addr6_entry(iter6));
 184         }
 185 #endif /* IPv6 */
 186         kfree(iface);
 187 }
 188
 189 /**
 190  * netlbl_unlhsh_hash - Hashing function for the hash table
 191  * @ifindex: the network interface/device to hash
 192  *
 193  * Description:
 194  * This is the hashing function for the unlabeled hash table, it returns the
 195  * bucket number for the given device/interface.  The caller is responsible for
 196  * ensuring that the hash table is protected with either a RCU read lock or
 197  * the hash table lock.
 198  *
 199  */
 200 static u32 netlbl_unlhsh_hash(int ifindex)
 201 {
 202         return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1);
 203 }
 204
 205 /**
 206  * netlbl_unlhsh_search_iface - Search for a matching interface entry
 207  * @ifindex: the network interface
 208  *
 209  * Description:
 210  * Searches the unlabeled connection hash table and returns a pointer to the
 211  * interface entry which matches @ifindex, otherwise NULL is returned.  The
 212  * caller is responsible for ensuring that the hash table is protected with
 213  * either a RCU read lock or the hash table lock.
 214  *
 215  */
 216 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
 217 {
 218         u32 bkt;
 219         struct list_head *bkt_list;
 220         struct netlbl_unlhsh_iface *iter;
 221
 222         bkt = netlbl_unlhsh_hash(ifindex);
 223         bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt];
 224         list_for_each_entry_rcu(iter, bkt_list, list)
 225                 if (iter->valid && iter->ifindex == ifindex)
 226                         return iter;
 227
 228         return NULL;
 229 }
 230
 231 /**
 232  * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
 233  * @iface: the associated interface entry
 234  * @addr: IPv4 address in network byte order
 235  * @mask: IPv4 address mask in network byte order
 236  * @secid: LSM secid value for entry
 237  *
 238  * Description:
 239  * Add a new address entry into the unlabeled connection hash table using the
 240  * interface entry specified by @iface.  On success zero is returned, otherwise
 241  * a negative value is returned.
 242  *
 243  */
 244 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
 245                                    const struct in_addr *addr,
 246                                    const struct in_addr *mask,
 247                                    u32 secid)
 248 {
 249         int ret_val;
 250         struct netlbl_unlhsh_addr4 *entry;
 251
 252         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 253         if (entry == NULL)
 254                 return -ENOMEM;
 255
 256         entry->list.addr = addr->s_addr & mask->s_addr;
 257         entry->list.mask = mask->s_addr;
 258         entry->list.valid = 1;
 259         entry->secid = secid;
 260
 261         spin_lock(&netlbl_unlhsh_lock);
 262         ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
 263         spin_unlock(&netlbl_unlhsh_lock);
 264
 265         if (ret_val != 0)
 266                 kfree(entry);
 267         return ret_val;
 268 }
 269
 270 #if IS_ENABLED(CONFIG_IPV6)
 271 /**
 272  * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
 273  * @iface: the associated interface entry
 274  * @addr: IPv6 address in network byte order
 275  * @mask: IPv6 address mask in network byte order
 276  * @secid: LSM secid value for entry
 277  *
 278  * Description:
 279  * Add a new address entry into the unlabeled connection hash table using the
 280  * interface entry specified by @iface.  On success zero is returned, otherwise
 281  * a negative value is returned.
 282  *
 283  */
 284 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
 285                                    const struct in6_addr *addr,
 286                                    const struct in6_addr *mask,
 287                                    u32 secid)
 288 {
 289         int ret_val;
 290         struct netlbl_unlhsh_addr6 *entry;
 291
 292         entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
 293         if (entry == NULL)
 294                 return -ENOMEM;
 295
 296         entry->list.addr = *addr;
 297         entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
 298         entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
 299         entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
 300         entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
 301         entry->list.mask = *mask;
 302         entry->list.valid = 1;
 303         entry->secid = secid;
 304
 305         spin_lock(&netlbl_unlhsh_lock);
 306         ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
 307         spin_unlock(&netlbl_unlhsh_lock);
 308
 309         if (ret_val != 0)
 310                 kfree(entry);
 311         return 0;
 312 }
 313 #endif /* IPv6 */
 314
 315 /**
 316  * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
 317  * @ifindex: network interface
 318  *
 319  * Description:
 320  * Add a new, empty, interface entry into the unlabeled connection hash table.
 321  * On success a pointer to the new interface entry is returned, on failure NULL
 322  * is returned.
 323  *
 324  */
 325 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
 326 {
 327         u32 bkt;
 328         struct netlbl_unlhsh_iface *iface;
 329
 330         iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
 331         if (iface == NULL)
 332                 return NULL;
 333
 334         iface->ifindex = ifindex;
 335         INIT_LIST_HEAD(&iface->addr4_list);
 336         INIT_LIST_HEAD(&iface->addr6_list);
 337         iface->valid = 1;
 338
 339         spin_lock(&netlbl_unlhsh_lock);
 340         if (ifindex > 0) {
 341                 bkt = netlbl_unlhsh_hash(ifindex);
 342                 if (netlbl_unlhsh_search_iface(ifindex) != NULL)
 343                         goto add_iface_failure;
 344                 list_add_tail_rcu(&iface->list,
 345                              &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]);
 346         } else {
 347                 INIT_LIST_HEAD(&iface->list);
 348                 if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL)
 349                         goto add_iface_failure;
 350                 rcu_assign_pointer(netlbl_unlhsh_def, iface);
 351         }
 352         spin_unlock(&netlbl_unlhsh_lock);
 353
 354         return iface;
 355
 356 add_iface_failure:
 357         spin_unlock(&netlbl_unlhsh_lock);
 358         kfree(iface);
 359         return NULL;
 360 }
 361
 362 /**
 363  * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
 364  * @net: network namespace
 365  * @dev_name: interface name
 366  * @addr: IP address in network byte order
 367  * @mask: address mask in network byte order
 368  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
 369  * @secid: LSM secid value for the entry
 370  * @audit_info: NetLabel audit information
 371  *
 372  * Description:
 373  * Adds a new entry to the unlabeled connection hash table.  Returns zero on
 374  * success, negative values on failure.
 375  *
 376  */
 377 int netlbl_unlhsh_add(struct net *net,
 378                       const char *dev_name,
 379                       const void *addr,
 380                       const void *mask,
 381                       u32 addr_len,
 382                       u32 secid,
 383                       struct netlbl_audit *audit_info)
 384 {
 385         int ret_val;
 386         int ifindex;
 387         struct net_device *dev;
 388         struct netlbl_unlhsh_iface *iface;
 389         struct audit_buffer *audit_buf = NULL;
 390         char *secctx = NULL;
 391         u32 secctx_len;
 392
 393         if (addr_len != sizeof(struct in_addr) &&
 394             addr_len != sizeof(struct in6_addr))
 395                 return -EINVAL;
 396
 397         rcu_read_lock();
 398         if (dev_name != NULL) {
 399                 dev = dev_get_by_name_rcu(net, dev_name);
 400                 if (dev == NULL) {
 401                         ret_val = -ENODEV;
 402                         goto unlhsh_add_return;
 403                 }
 404                 ifindex = dev->ifindex;
 405                 iface = netlbl_unlhsh_search_iface(ifindex);
 406         } else {
 407                 ifindex = 0;
 408                 iface = rcu_dereference(netlbl_unlhsh_def);
 409         }
 410         if (iface == NULL) {
 411                 iface = netlbl_unlhsh_add_iface(ifindex);
 412                 if (iface == NULL) {
 413                         ret_val = -ENOMEM;
 414                         goto unlhsh_add_return;
 415                 }
 416         }
 417         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
 418                                               audit_info);
 419         switch (addr_len) {
 420         case sizeof(struct in_addr): {
 421                 const struct in_addr *addr4 = addr;
 422                 const struct in_addr *mask4 = mask;
 423
 424                 ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
 425                 if (audit_buf != NULL)
 426                         netlbl_af4list_audit_addr(audit_buf, 1,
 427                                                   dev_name,
 428                                                   addr4->s_addr,
 429                                                   mask4->s_addr);
 430                 break;
 431         }
 432 #if IS_ENABLED(CONFIG_IPV6)
 433         case sizeof(struct in6_addr): {
 434                 const struct in6_addr *addr6 = addr;
 435                 const struct in6_addr *mask6 = mask;
 436
 437                 ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
 438                 if (audit_buf != NULL)
 439                         netlbl_af6list_audit_addr(audit_buf, 1,
 440                                                   dev_name,
 441                                                   addr6, mask6);
 442                 break;
 443         }
 444 #endif /* IPv6 */
 445         default:
 446                 ret_val = -EINVAL;
 447         }
 448         if (ret_val == 0)
 449                 atomic_inc(&netlabel_mgmt_protocount);
 450
 451 unlhsh_add_return:
 452         rcu_read_unlock();
 453         if (audit_buf != NULL) {
 454                 if (security_secid_to_secctx(secid,
 455                                              &secctx,
 456                                              &secctx_len) == 0) {
 457                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 458                         security_release_secctx(secctx, secctx_len);
 459                 }
 460                 audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
 461                 audit_log_end(audit_buf);
 462         }
 463         return ret_val;
 464 }
 465
 466 /**
 467  * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
 468  * @net: network namespace
 469  * @iface: interface entry
 470  * @addr: IP address
 471  * @mask: IP address mask
 472  * @audit_info: NetLabel audit information
 473  *
 474  * Description:
 475  * Remove an IP address entry from the unlabeled connection hash table.
 476  * Returns zero on success, negative values on failure.
 477  *
 478  */
 479 static int netlbl_unlhsh_remove_addr4(struct net *net,
 480                                       struct netlbl_unlhsh_iface *iface,
 481                                       const struct in_addr *addr,
 482                                       const struct in_addr *mask,
 483                                       struct netlbl_audit *audit_info)
 484 {
 485         struct netlbl_af4list *list_entry;
 486         struct netlbl_unlhsh_addr4 *entry;
 487         struct audit_buffer *audit_buf;
 488         struct net_device *dev;
 489         char *secctx;
 490         u32 secctx_len;
 491
 492         spin_lock(&netlbl_unlhsh_lock);
 493         list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
 494                                            &iface->addr4_list);
 495         spin_unlock(&netlbl_unlhsh_lock);
 496         if (list_entry != NULL)
 497                 entry = netlbl_unlhsh_addr4_entry(list_entry);
 498         else
 499                 entry = NULL;
 500
 501         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
 502                                               audit_info);
 503         if (audit_buf != NULL) {
 504                 dev = dev_get_by_index(net, iface->ifindex);
 505                 netlbl_af4list_audit_addr(audit_buf, 1,
 506                                           (dev != NULL ? dev->name : NULL),
 507                                           addr->s_addr, mask->s_addr);
 508                 if (dev != NULL)
 509                         dev_put(dev);
 510                 if (entry != NULL &&
 511                     security_secid_to_secctx(entry->secid,
 512                                              &secctx, &secctx_len) == 0) {
 513                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 514                         security_release_secctx(secctx, secctx_len);
 515                 }
 516                 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 517                 audit_log_end(audit_buf);
 518         }
 519
 520         if (entry == NULL)
 521                 return -ENOENT;
 522
 523         kfree_rcu(entry, rcu);
 524         return 0;
 525 }
 526
 527 #if IS_ENABLED(CONFIG_IPV6)
 528 /**
 529  * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
 530  * @net: network namespace
 531  * @iface: interface entry
 532  * @addr: IP address
 533  * @mask: IP address mask
 534  * @audit_info: NetLabel audit information
 535  *
 536  * Description:
 537  * Remove an IP address entry from the unlabeled connection hash table.
 538  * Returns zero on success, negative values on failure.
 539  *
 540  */
 541 static int netlbl_unlhsh_remove_addr6(struct net *net,
 542                                       struct netlbl_unlhsh_iface *iface,
 543                                       const struct in6_addr *addr,
 544                                       const struct in6_addr *mask,
 545                                       struct netlbl_audit *audit_info)
 546 {
 547         struct netlbl_af6list *list_entry;
 548         struct netlbl_unlhsh_addr6 *entry;
 549         struct audit_buffer *audit_buf;
 550         struct net_device *dev;
 551         char *secctx;
 552         u32 secctx_len;
 553
 554         spin_lock(&netlbl_unlhsh_lock);
 555         list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
 556         spin_unlock(&netlbl_unlhsh_lock);
 557         if (list_entry != NULL)
 558                 entry = netlbl_unlhsh_addr6_entry(list_entry);
 559         else
 560                 entry = NULL;
 561
 562         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
 563                                               audit_info);
 564         if (audit_buf != NULL) {
 565                 dev = dev_get_by_index(net, iface->ifindex);
 566                 netlbl_af6list_audit_addr(audit_buf, 1,
 567                                           (dev != NULL ? dev->name : NULL),
 568                                           addr, mask);
 569                 if (dev != NULL)
 570                         dev_put(dev);
 571                 if (entry != NULL &&
 572                     security_secid_to_secctx(entry->secid,
 573                                              &secctx, &secctx_len) == 0) {
 574                         audit_log_format(audit_buf, " sec_obj=%s", secctx);
 575                         security_release_secctx(secctx, secctx_len);
 576                 }
 577                 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 578                 audit_log_end(audit_buf);
 579         }
 580
 581         if (entry == NULL)
 582                 return -ENOENT;
 583
 584         kfree_rcu(entry, rcu);
 585         return 0;
 586 }
 587 #endif /* IPv6 */
 588
 589 /**
 590  * netlbl_unlhsh_condremove_iface - Remove an interface entry
 591  * @iface: the interface entry
 592  *
 593  * Description:
 594  * Remove an interface entry from the unlabeled connection hash table if it is
 595  * empty.  An interface entry is considered to be empty if there are no
 596  * address entries assigned to it.
 597  *
 598  */
 599 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
 600 {
 601         struct netlbl_af4list *iter4;
 602 #if IS_ENABLED(CONFIG_IPV6)
 603         struct netlbl_af6list *iter6;
 604 #endif /* IPv6 */
 605
 606         spin_lock(&netlbl_unlhsh_lock);
 607         netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
 608                 goto unlhsh_condremove_failure;
 609 #if IS_ENABLED(CONFIG_IPV6)
 610         netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
 611                 goto unlhsh_condremove_failure;
 612 #endif /* IPv6 */
 613         iface->valid = 0;
 614         if (iface->ifindex > 0)
 615                 list_del_rcu(&iface->list);
 616         else
 617                 RCU_INIT_POINTER(netlbl_unlhsh_def, NULL);
 618         spin_unlock(&netlbl_unlhsh_lock);
 619
 620         call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
 621         return;
 622
 623 unlhsh_condremove_failure:
 624         spin_unlock(&netlbl_unlhsh_lock);
 625 }
 626
 627 /**
 628  * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
 629  * @net: network namespace
 630  * @dev_name: interface name
 631  * @addr: IP address in network byte order
 632  * @mask: address mask in network byte order
 633  * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
 634  * @audit_info: NetLabel audit information
 635  *
 636  * Description:
 637  * Removes and existing entry from the unlabeled connection hash table.
 638  * Returns zero on success, negative values on failure.
 639  *
 640  */
 641 int netlbl_unlhsh_remove(struct net *net,
 642                          const char *dev_name,
 643                          const void *addr,
 644                          const void *mask,
 645                          u32 addr_len,
 646                          struct netlbl_audit *audit_info)
 647 {
 648         int ret_val;
 649         struct net_device *dev;
 650         struct netlbl_unlhsh_iface *iface;
 651
 652         if (addr_len != sizeof(struct in_addr) &&
 653             addr_len != sizeof(struct in6_addr))
 654                 return -EINVAL;
 655
 656         rcu_read_lock();
 657         if (dev_name != NULL) {
 658                 dev = dev_get_by_name_rcu(net, dev_name);
 659                 if (dev == NULL) {
 660                         ret_val = -ENODEV;
 661                         goto unlhsh_remove_return;
 662                 }
 663                 iface = netlbl_unlhsh_search_iface(dev->ifindex);
 664         } else
 665                 iface = rcu_dereference(netlbl_unlhsh_def);
 666         if (iface == NULL) {
 667                 ret_val = -ENOENT;
 668                 goto unlhsh_remove_return;
 669         }
 670         switch (addr_len) {
 671         case sizeof(struct in_addr):
 672                 ret_val = netlbl_unlhsh_remove_addr4(net,
 673                                                      iface, addr, mask,
 674                                                      audit_info);
 675                 break;
 676 #if IS_ENABLED(CONFIG_IPV6)
 677         case sizeof(struct in6_addr):
 678                 ret_val = netlbl_unlhsh_remove_addr6(net,
 679                                                      iface, addr, mask,
 680                                                      audit_info);
 681                 break;
 682 #endif /* IPv6 */
 683         default:
 684                 ret_val = -EINVAL;
 685         }
 686         if (ret_val == 0) {
 687                 netlbl_unlhsh_condremove_iface(iface);
 688                 atomic_dec(&netlabel_mgmt_protocount);
 689         }
 690
 691 unlhsh_remove_return:
 692         rcu_read_unlock();
 693         return ret_val;
 694 }
 695
 696 /*
 697  * General Helper Functions
 698  */
 699
 700 /**
 701  * netlbl_unlhsh_netdev_handler - Network device notification handler
 702  * @this: notifier block
 703  * @event: the event
 704  * @ptr: the netdevice notifier info (cast to void)
 705  *
 706  * Description:
 707  * Handle network device events, although at present all we care about is a
 708  * network device going away.  In the case of a device going away we clear any
 709  * related entries from the unlabeled connection hash table.
 710  *
 711  */
 712 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
 713                                         unsigned long event, void *ptr)
 714 {
 715         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 716         struct netlbl_unlhsh_iface *iface = NULL;
 717
 718         if (!net_eq(dev_net(dev), &init_net))
 719                 return NOTIFY_DONE;
 720
 721         /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
 722         if (event == NETDEV_DOWN) {
 723                 spin_lock(&netlbl_unlhsh_lock);
 724                 iface = netlbl_unlhsh_search_iface(dev->ifindex);
 725                 if (iface != NULL && iface->valid) {
 726                         iface->valid = 0;
 727                         list_del_rcu(&iface->list);
 728                 } else
 729                         iface = NULL;
 730                 spin_unlock(&netlbl_unlhsh_lock);
 731         }
 732
 733         if (iface != NULL)
 734                 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
 735
 736         return NOTIFY_DONE;
 737 }
 738
 739 /**
 740  * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
 741  * @value: desired value
 742  * @audit_info: NetLabel audit information
 743  *
 744  * Description:
 745  * Set the value of the unlabeled accept flag to @value.
 746  *
 747  */
 748 static void netlbl_unlabel_acceptflg_set(u8 value,
 749                                          struct netlbl_audit *audit_info)
 750 {
 751         struct audit_buffer *audit_buf;
 752         u8 old_val;
 753
 754         old_val = netlabel_unlabel_acceptflg;
 755         netlabel_unlabel_acceptflg = value;
 756         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
 757                                               audit_info);
 758         if (audit_buf != NULL) {
 759                 audit_log_format(audit_buf,
 760                                  " unlbl_accept=%u old=%u", value, old_val);
 761                 audit_log_end(audit_buf);
 762         }
 763 }
 764
 765 /**
 766  * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
 767  * @info: the Generic NETLINK info block
 768  * @addr: the IP address
 769  * @mask: the IP address mask
 770  * @len: the address length
 771  *
 772  * Description:
 773  * Examine the Generic NETLINK message and extract the IP address information.
 774  * Returns zero on success, negative values on failure.
 775  *
 776  */
 777 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
 778                                        void **addr,
 779                                        void **mask,
 780                                        u32 *len)
 781 {
 782         u32 addr_len;
 783
 784         if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR]) {
 785                 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
 786                 if (addr_len != sizeof(struct in_addr) &&
 787                     addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
 788                         return -EINVAL;
 789                 *len = addr_len;
 790                 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
 791                 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
 792                 return 0;
 793         } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
 794                 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
 795                 if (addr_len != sizeof(struct in6_addr) &&
 796                     addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
 797                         return -EINVAL;
 798                 *len = addr_len;
 799                 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
 800                 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
 801                 return 0;
 802         }
 803
 804         return -EINVAL;
 805 }
 806
 807 /*
 808  * NetLabel Command Handlers
 809  */
 810
 811 /**
 812  * netlbl_unlabel_accept - Handle an ACCEPT message
 813  * @skb: the NETLINK buffer
 814  * @info: the Generic NETLINK info block
 815  *
 816  * Description:
 817  * Process a user generated ACCEPT message and set the accept flag accordingly.
 818  * Returns zero on success, negative values on failure.
 819  *
 820  */
 821 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
 822 {
 823         u8 value;
 824         struct netlbl_audit audit_info;
 825
 826         if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
 827                 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
 828                 if (value == 1 || value == 0) {
 829                         netlbl_netlink_auditinfo(skb, &audit_info);
 830                         netlbl_unlabel_acceptflg_set(value, &audit_info);
 831                         return 0;
 832                 }
 833         }
 834
 835         return -EINVAL;
 836 }
 837
 838 /**
 839  * netlbl_unlabel_list - Handle a LIST message
 840  * @skb: the NETLINK buffer
 841  * @info: the Generic NETLINK info block
 842  *
 843  * Description:
 844  * Process a user generated LIST message and respond with the current status.
 845  * Returns zero on success, negative values on failure.
 846  *
 847  */
 848 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
 849 {
 850         int ret_val = -EINVAL;
 851         struct sk_buff *ans_skb;
 852         void *data;
 853
 854         ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 855         if (ans_skb == NULL)
 856                 goto list_failure;
 857         data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
 858                                  0, NLBL_UNLABEL_C_LIST);
 859         if (data == NULL) {
 860                 ret_val = -ENOMEM;
 861                 goto list_failure;
 862         }
 863
 864         ret_val = nla_put_u8(ans_skb,
 865                              NLBL_UNLABEL_A_ACPTFLG,
 866                              netlabel_unlabel_acceptflg);
 867         if (ret_val != 0)
 868                 goto list_failure;
 869
 870         genlmsg_end(ans_skb, data);
 871         return genlmsg_reply(ans_skb, info);
 872
 873 list_failure:
 874         kfree_skb(ans_skb);
 875         return ret_val;
 876 }
 877
 878 /**
 879  * netlbl_unlabel_staticadd - Handle a STATICADD message
 880  * @skb: the NETLINK buffer
 881  * @info: the Generic NETLINK info block
 882  *
 883  * Description:
 884  * Process a user generated STATICADD message and add a new unlabeled
 885  * connection entry to the hash table.  Returns zero on success, negative
 886  * values on failure.
 887  *
 888  */
 889 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
 890                                     struct genl_info *info)
 891 {
 892         int ret_val;
 893         char *dev_name;
 894         void *addr;
 895         void *mask;
 896         u32 addr_len;
 897         u32 secid;
 898         struct netlbl_audit audit_info;
 899
 900         /* Don't allow users to add both IPv4 and IPv6 addresses for a
 901          * single entry.  However, allow users to create two entries, one each
 902          * for IPv4 and IPv4, with the same LSM security context which should
 903          * achieve the same result. */
 904         if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
 905             !info->attrs[NLBL_UNLABEL_A_IFACE] ||
 906             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 907                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 908               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 909                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 910                 return -EINVAL;
 911
 912         netlbl_netlink_auditinfo(skb, &audit_info);
 913
 914         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 915         if (ret_val != 0)
 916                 return ret_val;
 917         dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
 918         ret_val = security_secctx_to_secid(
 919                                   nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 920                                   nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 921                                   &secid);
 922         if (ret_val != 0)
 923                 return ret_val;
 924
 925         return netlbl_unlhsh_add(&init_net,
 926                                  dev_name, addr, mask, addr_len, secid,
 927                                  &audit_info);
 928 }
 929
 930 /**
 931  * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
 932  * @skb: the NETLINK buffer
 933  * @info: the Generic NETLINK info block
 934  *
 935  * Description:
 936  * Process a user generated STATICADDDEF message and add a new default
 937  * unlabeled connection entry.  Returns zero on success, negative values on
 938  * failure.
 939  *
 940  */
 941 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
 942                                        struct genl_info *info)
 943 {
 944         int ret_val;
 945         void *addr;
 946         void *mask;
 947         u32 addr_len;
 948         u32 secid;
 949         struct netlbl_audit audit_info;
 950
 951         /* Don't allow users to add both IPv4 and IPv6 addresses for a
 952          * single entry.  However, allow users to create two entries, one each
 953          * for IPv4 and IPv6, with the same LSM security context which should
 954          * achieve the same result. */
 955         if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
 956             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
 957                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
 958               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
 959                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
 960                 return -EINVAL;
 961
 962         netlbl_netlink_auditinfo(skb, &audit_info);
 963
 964         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
 965         if (ret_val != 0)
 966                 return ret_val;
 967         ret_val = security_secctx_to_secid(
 968                                   nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 969                                   nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
 970                                   &secid);
 971         if (ret_val != 0)
 972                 return ret_val;
 973
 974         return netlbl_unlhsh_add(&init_net,
 975                                  NULL, addr, mask, addr_len, secid,
 976                                  &audit_info);
 977 }
 978
 979 /**
 980  * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
 981  * @skb: the NETLINK buffer
 982  * @info: the Generic NETLINK info block
 983  *
 984  * Description:
 985  * Process a user generated STATICREMOVE message and remove the specified
 986  * unlabeled connection entry.  Returns zero on success, negative values on
 987  * failure.
 988  *
 989  */
 990 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
 991                                        struct genl_info *info)
 992 {
 993         int ret_val;
 994         char *dev_name;
 995         void *addr;
 996         void *mask;
 997         u32 addr_len;
 998         struct netlbl_audit audit_info;
 999
1000         /* See the note in netlbl_unlabel_staticadd() about not allowing both
1001          * IPv4 and IPv6 in the same entry. */
1002         if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
1003             !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1004                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1005               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1006                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1007                 return -EINVAL;
1008
1009         netlbl_netlink_auditinfo(skb, &audit_info);
1010
1011         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1012         if (ret_val != 0)
1013                 return ret_val;
1014         dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1015
1016         return netlbl_unlhsh_remove(&init_net,
1017                                     dev_name, addr, mask, addr_len,
1018                                     &audit_info);
1019 }
1020
1021 /**
1022  * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1023  * @skb: the NETLINK buffer
1024  * @info: the Generic NETLINK info block
1025  *
1026  * Description:
1027  * Process a user generated STATICREMOVEDEF message and remove the default
1028  * unlabeled connection entry.  Returns zero on success, negative values on
1029  * failure.
1030  *
1031  */
1032 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1033                                           struct genl_info *info)
1034 {
1035         int ret_val;
1036         void *addr;
1037         void *mask;
1038         u32 addr_len;
1039         struct netlbl_audit audit_info;
1040
1041         /* See the note in netlbl_unlabel_staticadd() about not allowing both
1042          * IPv4 and IPv6 in the same entry. */
1043         if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1044                !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1045               (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1046                !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1047                 return -EINVAL;
1048
1049         netlbl_netlink_auditinfo(skb, &audit_info);
1050
1051         ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1052         if (ret_val != 0)
1053                 return ret_val;
1054
1055         return netlbl_unlhsh_remove(&init_net,
1056                                     NULL, addr, mask, addr_len,
1057                                     &audit_info);
1058 }
1059
1060
1061 /**
1062  * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1063  * @cmd: command/message
1064  * @iface: the interface entry
1065  * @addr4: the IPv4 address entry
1066  * @addr6: the IPv6 address entry
1067  * @arg: the netlbl_unlhsh_walk_arg structure
1068  *
1069  * Description:
1070  * This function is designed to be used to generate a response for a
1071  * STATICLIST or STATICLISTDEF message.  When called either @addr4 or @addr6
1072  * can be specified, not both, the other unspecified entry should be set to
1073  * NULL by the caller.  Returns the size of the message on success, negative
1074  * values on failure.
1075  *
1076  */
1077 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1078                                        const struct netlbl_unlhsh_iface *iface,
1079                                        const struct netlbl_unlhsh_addr4 *addr4,
1080                                        const struct netlbl_unlhsh_addr6 *addr6,
1081                                        void *arg)
1082 {
1083         int ret_val = -ENOMEM;
1084         struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1085         struct net_device *dev;
1086         void *data;
1087         u32 secid;
1088         char *secctx;
1089         u32 secctx_len;
1090
1091         data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
1092                            cb_arg->seq, &netlbl_unlabel_gnl_family,
1093                            NLM_F_MULTI, cmd);
1094         if (data == NULL)
1095                 goto list_cb_failure;
1096
1097         if (iface->ifindex > 0) {
1098                 dev = dev_get_by_index(&init_net, iface->ifindex);
1099                 if (!dev) {
1100                         ret_val = -ENODEV;
1101                         goto list_cb_failure;
1102                 }
1103                 ret_val = nla_put_string(cb_arg->skb,
1104                                          NLBL_UNLABEL_A_IFACE, dev->name);
1105                 dev_put(dev);
1106                 if (ret_val != 0)
1107                         goto list_cb_failure;
1108         }
1109
1110         if (addr4) {
1111                 struct in_addr addr_struct;
1112
1113                 addr_struct.s_addr = addr4->list.addr;
1114                 ret_val = nla_put_in_addr(cb_arg->skb,
1115                                           NLBL_UNLABEL_A_IPV4ADDR,
1116                                           addr_struct.s_addr);
1117                 if (ret_val != 0)
1118                         goto list_cb_failure;
1119
1120                 addr_struct.s_addr = addr4->list.mask;
1121                 ret_val = nla_put_in_addr(cb_arg->skb,
1122                                           NLBL_UNLABEL_A_IPV4MASK,
1123                                           addr_struct.s_addr);
1124                 if (ret_val != 0)
1125                         goto list_cb_failure;
1126
1127                 secid = addr4->secid;
1128         } else {
1129                 ret_val = nla_put_in6_addr(cb_arg->skb,
1130                                            NLBL_UNLABEL_A_IPV6ADDR,
1131                                            &addr6->list.addr);
1132                 if (ret_val != 0)
1133                         goto list_cb_failure;
1134
1135                 ret_val = nla_put_in6_addr(cb_arg->skb,
1136                                            NLBL_UNLABEL_A_IPV6MASK,
1137                                            &addr6->list.mask);
1138                 if (ret_val != 0)
1139                         goto list_cb_failure;
1140
1141                 secid = addr6->secid;
1142         }
1143
1144         ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1145         if (ret_val != 0)
1146                 goto list_cb_failure;
1147         ret_val = nla_put(cb_arg->skb,
1148                           NLBL_UNLABEL_A_SECCTX,
1149                           secctx_len,
1150                           secctx);
1151         security_release_secctx(secctx, secctx_len);
1152         if (ret_val != 0)
1153                 goto list_cb_failure;
1154
1155         cb_arg->seq++;
1156         genlmsg_end(cb_arg->skb, data);
1157         return 0;
1158
1159 list_cb_failure:
1160         genlmsg_cancel(cb_arg->skb, data);
1161         return ret_val;
1162 }
1163
1164 /**
1165  * netlbl_unlabel_staticlist - Handle a STATICLIST message
1166  * @skb: the NETLINK buffer
1167  * @cb: the NETLINK callback
1168  *
1169  * Description:
1170  * Process a user generated STATICLIST message and dump the unlabeled
1171  * connection hash table in a form suitable for use in a kernel generated
1172  * STATICLIST message.  Returns the length of @skb.
1173  *
1174  */
1175 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1176                                      struct netlink_callback *cb)
1177 {
1178         struct netlbl_unlhsh_walk_arg cb_arg;
1179         u32 skip_bkt = cb->args[0];
1180         u32 skip_chain = cb->args[1];
1181         u32 iter_bkt;
1182         u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1183         struct netlbl_unlhsh_iface *iface;
1184         struct list_head *iter_list;
1185         struct netlbl_af4list *addr4;
1186 #if IS_ENABLED(CONFIG_IPV6)
1187         struct netlbl_af6list *addr6;
1188 #endif
1189
1190         cb_arg.nl_cb = cb;
1191         cb_arg.skb = skb;
1192         cb_arg.seq = cb->nlh->nlmsg_seq;
1193
1194         rcu_read_lock();
1195         for (iter_bkt = skip_bkt;
1196              iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1197              iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1198                 iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1199                 list_for_each_entry_rcu(iface, iter_list, list) {
1200                         if (!iface->valid ||
1201                             iter_chain++ < skip_chain)
1202                                 continue;
1203                         netlbl_af4list_foreach_rcu(addr4,
1204                                                    &iface->addr4_list) {
1205                                 if (iter_addr4++ < cb->args[2])
1206                                         continue;
1207                                 if (netlbl_unlabel_staticlist_gen(
1208                                               NLBL_UNLABEL_C_STATICLIST,
1209                                               iface,
1210                                               netlbl_unlhsh_addr4_entry(addr4),
1211                                               NULL,
1212                                               &cb_arg) < 0) {
1213                                         iter_addr4--;
1214                                         iter_chain--;
1215                                         goto unlabel_staticlist_return;
1216                                 }
1217                         }
1218 #if IS_ENABLED(CONFIG_IPV6)
1219                         netlbl_af6list_foreach_rcu(addr6,
1220                                                    &iface->addr6_list) {
1221                                 if (iter_addr6++ < cb->args[3])
1222                                         continue;
1223                                 if (netlbl_unlabel_staticlist_gen(
1224                                               NLBL_UNLABEL_C_STATICLIST,
1225                                               iface,
1226                                               NULL,
1227                                               netlbl_unlhsh_addr6_entry(addr6),
1228                                               &cb_arg) < 0) {
1229                                         iter_addr6--;
1230                                         iter_chain--;
1231                                         goto unlabel_staticlist_return;
1232                                 }
1233                         }
1234 #endif /* IPv6 */
1235                 }
1236         }
1237
1238 unlabel_staticlist_return:
1239         rcu_read_unlock();
1240         cb->args[0] = iter_bkt;
1241         cb->args[1] = iter_chain;
1242         cb->args[2] = iter_addr4;
1243         cb->args[3] = iter_addr6;
1244         return skb->len;
1245 }
1246
1247 /**
1248  * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1249  * @skb: the NETLINK buffer
1250  * @cb: the NETLINK callback
1251  *
1252  * Description:
1253  * Process a user generated STATICLISTDEF message and dump the default
1254  * unlabeled connection entry in a form suitable for use in a kernel generated
1255  * STATICLISTDEF message.  Returns the length of @skb.
1256  *
1257  */
1258 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1259                                         struct netlink_callback *cb)
1260 {
1261         struct netlbl_unlhsh_walk_arg cb_arg;
1262         struct netlbl_unlhsh_iface *iface;
1263         u32 iter_addr4 = 0, iter_addr6 = 0;
1264         struct netlbl_af4list *addr4;
1265 #if IS_ENABLED(CONFIG_IPV6)
1266         struct netlbl_af6list *addr6;
1267 #endif
1268
1269         cb_arg.nl_cb = cb;
1270         cb_arg.skb = skb;
1271         cb_arg.seq = cb->nlh->nlmsg_seq;
1272
1273         rcu_read_lock();
1274         iface = rcu_dereference(netlbl_unlhsh_def);
1275         if (iface == NULL || !iface->valid)
1276                 goto unlabel_staticlistdef_return;
1277
1278         netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1279                 if (iter_addr4++ < cb->args[0])
1280                         continue;
1281                 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1282                                               iface,
1283                                               netlbl_unlhsh_addr4_entry(addr4),
1284                                               NULL,
1285                                               &cb_arg) < 0) {
1286                         iter_addr4--;
1287                         goto unlabel_staticlistdef_return;
1288                 }
1289         }
1290 #if IS_ENABLED(CONFIG_IPV6)
1291         netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1292                 if (iter_addr6++ < cb->args[1])
1293                         continue;
1294                 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1295                                               iface,
1296                                               NULL,
1297                                               netlbl_unlhsh_addr6_entry(addr6),
1298                                               &cb_arg) < 0) {
1299                         iter_addr6--;
1300                         goto unlabel_staticlistdef_return;
1301                 }
1302         }
1303 #endif /* IPv6 */
1304
1305 unlabel_staticlistdef_return:
1306         rcu_read_unlock();
1307         cb->args[0] = iter_addr4;
1308         cb->args[1] = iter_addr6;
1309         return skb->len;
1310 }
1311
1312 /*
1313  * NetLabel Generic NETLINK Command Definitions
1314  */
1315
1316 static const struct genl_ops netlbl_unlabel_genl_ops[] = {
1317         {
1318         .cmd = NLBL_UNLABEL_C_STATICADD,
1319         .flags = GENL_ADMIN_PERM,
1320         .policy = netlbl_unlabel_genl_policy,
1321         .doit = netlbl_unlabel_staticadd,
1322         .dumpit = NULL,
1323         },
1324         {
1325         .cmd = NLBL_UNLABEL_C_STATICREMOVE,
1326         .flags = GENL_ADMIN_PERM,
1327         .policy = netlbl_unlabel_genl_policy,
1328         .doit = netlbl_unlabel_staticremove,
1329         .dumpit = NULL,
1330         },
1331         {
1332         .cmd = NLBL_UNLABEL_C_STATICLIST,
1333         .flags = 0,
1334         .policy = netlbl_unlabel_genl_policy,
1335         .doit = NULL,
1336         .dumpit = netlbl_unlabel_staticlist,
1337         },
1338         {
1339         .cmd = NLBL_UNLABEL_C_STATICADDDEF,
1340         .flags = GENL_ADMIN_PERM,
1341         .policy = netlbl_unlabel_genl_policy,
1342         .doit = netlbl_unlabel_staticadddef,
1343         .dumpit = NULL,
1344         },
1345         {
1346         .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1347         .flags = GENL_ADMIN_PERM,
1348         .policy = netlbl_unlabel_genl_policy,
1349         .doit = netlbl_unlabel_staticremovedef,
1350         .dumpit = NULL,
1351         },
1352         {
1353         .cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1354         .flags = 0,
1355         .policy = netlbl_unlabel_genl_policy,
1356         .doit = NULL,
1357         .dumpit = netlbl_unlabel_staticlistdef,
1358         },
1359         {
1360         .cmd = NLBL_UNLABEL_C_ACCEPT,
1361         .flags = GENL_ADMIN_PERM,
1362         .policy = netlbl_unlabel_genl_policy,
1363         .doit = netlbl_unlabel_accept,
1364         .dumpit = NULL,
1365         },
1366         {
1367         .cmd = NLBL_UNLABEL_C_LIST,
1368         .flags = 0,
1369         .policy = netlbl_unlabel_genl_policy,
1370         .doit = netlbl_unlabel_list,
1371         .dumpit = NULL,
1372         },
1373 };
1374
1375 static struct genl_family netlbl_unlabel_gnl_family __ro_after_init = {
1376         .hdrsize = 0,
1377         .name = NETLBL_NLTYPE_UNLABELED_NAME,
1378         .version = NETLBL_PROTO_VERSION,
1379         .maxattr = NLBL_UNLABEL_A_MAX,
1380         .module = THIS_MODULE,
1381         .ops = netlbl_unlabel_genl_ops,
1382         .n_ops = ARRAY_SIZE(netlbl_unlabel_genl_ops),
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(&netlbl_unlabel_gnl_family);
1400 }
1401
1402 /*
1403  * NetLabel KAPI Hooks
1404  */
1405
1406 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1407         .notifier_call = netlbl_unlhsh_netdev_handler,
1408 };
1409
1410 /**
1411  * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1412  * @size: the number of bits to use for the hash buckets
1413  *
1414  * Description:
1415  * Initializes the unlabeled connection hash table and registers a network
1416  * device notification handler.  This function should only be called by the
1417  * NetLabel subsystem itself during initialization.  Returns zero on success,
1418  * non-zero values on error.
1419  *
1420  */
1421 int __init netlbl_unlabel_init(u32 size)
1422 {
1423         u32 iter;
1424         struct netlbl_unlhsh_tbl *hsh_tbl;
1425
1426         if (size == 0)
1427                 return -EINVAL;
1428
1429         hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1430         if (hsh_tbl == NULL)
1431                 return -ENOMEM;
1432         hsh_tbl->size = 1 << size;
1433         hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1434                                sizeof(struct list_head),
1435                                GFP_KERNEL);
1436         if (hsh_tbl->tbl == NULL) {
1437                 kfree(hsh_tbl);
1438                 return -ENOMEM;
1439         }
1440         for (iter = 0; iter < hsh_tbl->size; iter++)
1441                 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1442
1443         spin_lock(&netlbl_unlhsh_lock);
1444         rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1445         spin_unlock(&netlbl_unlhsh_lock);
1446
1447         register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1448
1449         return 0;
1450 }
1451
1452 /**
1453  * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1454  * @skb: the packet
1455  * @family: protocol family
1456  * @secattr: the security attributes
1457  *
1458  * Description:
1459  * Determine the security attributes, if any, for an unlabled packet and return
1460  * them in @secattr.  Returns zero on success and negative values on failure.
1461  *
1462  */
1463 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1464                            u16 family,
1465                            struct netlbl_lsm_secattr *secattr)
1466 {
1467         struct netlbl_unlhsh_iface *iface;
1468
1469         rcu_read_lock();
1470         iface = netlbl_unlhsh_search_iface(skb->skb_iif);
1471         if (iface == NULL)
1472                 iface = rcu_dereference(netlbl_unlhsh_def);
1473         if (iface == NULL || !iface->valid)
1474                 goto unlabel_getattr_nolabel;
1475
1476 #if IS_ENABLED(CONFIG_IPV6)
1477         /* When resolving a fallback label, check the sk_buff version as
1478          * it is possible (e.g. SCTP) to have family = PF_INET6 while
1479          * receiving ip_hdr(skb)->version = 4.
1480          */
1481         if (family == PF_INET6 && ip_hdr(skb)->version == 4)
1482                 family = PF_INET;
1483 #endif /* IPv6 */
1484
1485         switch (family) {
1486         case PF_INET: {
1487                 struct iphdr *hdr4;
1488                 struct netlbl_af4list *addr4;
1489
1490                 hdr4 = ip_hdr(skb);
1491                 addr4 = netlbl_af4list_search(hdr4->saddr,
1492                                               &iface->addr4_list);
1493                 if (addr4 == NULL)
1494                         goto unlabel_getattr_nolabel;
1495                 secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1496                 break;
1497         }
1498 #if IS_ENABLED(CONFIG_IPV6)
1499         case PF_INET6: {
1500                 struct ipv6hdr *hdr6;
1501                 struct netlbl_af6list *addr6;
1502
1503                 hdr6 = ipv6_hdr(skb);
1504                 addr6 = netlbl_af6list_search(&hdr6->saddr,
1505                                               &iface->addr6_list);
1506                 if (addr6 == NULL)
1507                         goto unlabel_getattr_nolabel;
1508                 secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1509                 break;
1510         }
1511 #endif /* IPv6 */
1512         default:
1513                 goto unlabel_getattr_nolabel;
1514         }
1515         rcu_read_unlock();
1516
1517         secattr->flags |= NETLBL_SECATTR_SECID;
1518         secattr->type = NETLBL_NLTYPE_UNLABELED;
1519         return 0;
1520
1521 unlabel_getattr_nolabel:
1522         rcu_read_unlock();
1523         if (netlabel_unlabel_acceptflg == 0)
1524                 return -ENOMSG;
1525         secattr->type = NETLBL_NLTYPE_UNLABELED;
1526         return 0;
1527 }
1528
1529 /**
1530  * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1531  *
1532  * Description:
1533  * Set the default NetLabel configuration to allow incoming unlabeled packets
1534  * and to send unlabeled network traffic by default.
1535  *
1536  */
1537 int __init netlbl_unlabel_defconf(void)
1538 {
1539         int ret_val;
1540         struct netlbl_dom_map *entry;
1541         struct netlbl_audit audit_info;
1542
1543         /* Only the kernel is allowed to call this function and the only time
1544          * it is called is at bootup before the audit subsystem is reporting
1545          * messages so don't worry to much about these values. */
1546         security_task_getsecid(current, &audit_info.secid);
1547         audit_info.loginuid = GLOBAL_ROOT_UID;
1548         audit_info.sessionid = 0;
1549
1550         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1551         if (entry == NULL)
1552                 return -ENOMEM;
1553         entry->family = AF_UNSPEC;
1554         entry->def.type = NETLBL_NLTYPE_UNLABELED;
1555         ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1556         if (ret_val != 0)
1557                 return ret_val;
1558
1559         netlbl_unlabel_acceptflg_set(1, &audit_info);
1560
1561         return 0;
1562 }