LXR linux/net/netlabel/netlabel

   1/*
   2 * NetLabel Management Support
   3 *
   4 * This file defines the management functions for the NetLabel system.  The
   5 * NetLabel system manages static and dynamic label mappings for network
   6 * 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/socket.h>
  33#include <linux/string.h>
  34#include <linux/skbuff.h>
  35#include <linux/in.h>
  36#include <linux/in6.h>
  37#include <linux/slab.h>
  38#include <net/sock.h>
  39#include <net/netlink.h>
  40#include <net/genetlink.h>
  41#include <net/ip.h>
  42#include <net/ipv6.h>
  43#include <net/netlabel.h>
  44#include <net/cipso_ipv4.h>
  45#include <linux/atomic.h>
  46
  47#include "netlabel_domainhash.h"
  48#include "netlabel_user.h"
  49#include "netlabel_mgmt.h"
  50
  51/* NetLabel configured protocol counter */
  52atomic_t netlabel_mgmt_protocount = ATOMIC_INIT(0);
  53
  54/* Argument struct for netlbl_domhsh_walk() */
  55struct netlbl_domhsh_walk_arg {
  56        struct netlink_callback *nl_cb;
  57        struct sk_buff *skb;
  58        u32 seq;
  59};
  60
  61/* NetLabel Generic NETLINK CIPSOv4 family */
  62static struct genl_family netlbl_mgmt_gnl_family = {
  63        .id = GENL_ID_GENERATE,
  64        .hdrsize = 0,
  65        .name = NETLBL_NLTYPE_MGMT_NAME,
  66        .version = NETLBL_PROTO_VERSION,
  67        .maxattr = NLBL_MGMT_A_MAX,
  68};
  69
  70/* NetLabel Netlink attribute policy */
  71static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
  72        [NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
  73        [NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
  74        [NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
  75        [NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
  76};
  77
  78/*
  79 * Helper Functions
  80 */
  81
  82/**
  83 * netlbl_mgmt_add - Handle an ADD message
  84 * @info: the Generic NETLINK info block
  85 * @audit_info: NetLabel audit information
  86 *
  87 * Description:
  88 * Helper function for the ADD and ADDDEF messages to add the domain mappings
  89 * from the message to the hash table.  See netlabel.h for a description of the
  90 * message format.  Returns zero on success, negative values on failure.
  91 *
  92 */
  93static int netlbl_mgmt_add_common(struct genl_info *info,
  94                                  struct netlbl_audit *audit_info)
  95{
  96        int ret_val = -EINVAL;
  97        struct netlbl_dom_map *entry = NULL;
  98        struct netlbl_domaddr_map *addrmap = NULL;
  99        struct cipso_v4_doi *cipsov4 = NULL;
 100        u32 tmp_val;
 101
 102        entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 103        if (entry == NULL) {
 104                ret_val = -ENOMEM;
 105                goto add_failure;
 106        }
 107        entry->def.type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
 108        if (info->attrs[NLBL_MGMT_A_DOMAIN]) {
 109                size_t tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
 110                entry->domain = kmalloc(tmp_size, GFP_KERNEL);
 111                if (entry->domain == NULL) {
 112                        ret_val = -ENOMEM;
 113                        goto add_failure;
 114                }
 115                nla_strlcpy(entry->domain,
 116                            info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
 117        }
 118
 119        /* NOTE: internally we allow/use a entry->def.type value of
 120         *       NETLBL_NLTYPE_ADDRSELECT but we don't currently allow users
 121         *       to pass that as a protocol value because we need to know the
 122         *       "real" protocol */
 123
 124        switch (entry->def.type) {
 125        case NETLBL_NLTYPE_UNLABELED:
 126                break;
 127        case NETLBL_NLTYPE_CIPSOV4:
 128                if (!info->attrs[NLBL_MGMT_A_CV4DOI])
 129                        goto add_failure;
 130
 131                tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
 132                cipsov4 = cipso_v4_doi_getdef(tmp_val);
 133                if (cipsov4 == NULL)
 134                        goto add_failure;
 135                entry->def.cipso = cipsov4;
 136                break;
 137        default:
 138                goto add_failure;
 139        }
 140
 141        if (info->attrs[NLBL_MGMT_A_IPV4ADDR]) {
 142                struct in_addr *addr;
 143                struct in_addr *mask;
 144                struct netlbl_domaddr4_map *map;
 145
 146                addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL);
 147                if (addrmap == NULL) {
 148                        ret_val = -ENOMEM;
 149                        goto add_failure;
 150                }
 151                INIT_LIST_HEAD(&addrmap->list4);
 152                INIT_LIST_HEAD(&addrmap->list6);
 153
 154                if (nla_len(info->attrs[NLBL_MGMT_A_IPV4ADDR]) !=
 155                    sizeof(struct in_addr)) {
 156                        ret_val = -EINVAL;
 157                        goto add_failure;
 158                }
 159                if (nla_len(info->attrs[NLBL_MGMT_A_IPV4MASK]) !=
 160                    sizeof(struct in_addr)) {
 161                        ret_val = -EINVAL;
 162                        goto add_failure;
 163                }
 164                addr = nla_data(info->attrs[NLBL_MGMT_A_IPV4ADDR]);
 165                mask = nla_data(info->attrs[NLBL_MGMT_A_IPV4MASK]);
 166
 167                map = kzalloc(sizeof(*map), GFP_KERNEL);
 168                if (map == NULL) {
 169                        ret_val = -ENOMEM;
 170                        goto add_failure;
 171                }
 172                map->list.addr = addr->s_addr & mask->s_addr;
 173                map->list.mask = mask->s_addr;
 174                map->list.valid = 1;
 175                map->def.type = entry->def.type;
 176                if (cipsov4)
 177                        map->def.cipso = cipsov4;
 178
 179                ret_val = netlbl_af4list_add(&map->list, &addrmap->list4);
 180                if (ret_val != 0) {
 181                        kfree(map);
 182                        goto add_failure;
 183                }
 184
 185                entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 186                entry->def.addrsel = addrmap;
 187#if IS_ENABLED(CONFIG_IPV6)
 188        } else if (info->attrs[NLBL_MGMT_A_IPV6ADDR]) {
 189                struct in6_addr *addr;
 190                struct in6_addr *mask;
 191                struct netlbl_domaddr6_map *map;
 192
 193                addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL);
 194                if (addrmap == NULL) {
 195                        ret_val = -ENOMEM;
 196                        goto add_failure;
 197                }
 198                INIT_LIST_HEAD(&addrmap->list4);
 199                INIT_LIST_HEAD(&addrmap->list6);
 200
 201                if (nla_len(info->attrs[NLBL_MGMT_A_IPV6ADDR]) !=
 202                    sizeof(struct in6_addr)) {
 203                        ret_val = -EINVAL;
 204                        goto add_failure;
 205                }
 206                if (nla_len(info->attrs[NLBL_MGMT_A_IPV6MASK]) !=
 207                    sizeof(struct in6_addr)) {
 208                        ret_val = -EINVAL;
 209                        goto add_failure;
 210                }
 211                addr = nla_data(info->attrs[NLBL_MGMT_A_IPV6ADDR]);
 212                mask = nla_data(info->attrs[NLBL_MGMT_A_IPV6MASK]);
 213
 214                map = kzalloc(sizeof(*map), GFP_KERNEL);
 215                if (map == NULL) {
 216                        ret_val = -ENOMEM;
 217                        goto add_failure;
 218                }
 219                map->list.addr = *addr;
 220                map->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
 221                map->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
 222                map->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
 223                map->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
 224                map->list.mask = *mask;
 225                map->list.valid = 1;
 226                map->def.type = entry->def.type;
 227
 228                ret_val = netlbl_af6list_add(&map->list, &addrmap->list6);
 229                if (ret_val != 0) {
 230                        kfree(map);
 231                        goto add_failure;
 232                }
 233
 234                entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
 235                entry->def.addrsel = addrmap;
 236#endif /* IPv6 */
 237        }
 238
 239        ret_val = netlbl_domhsh_add(entry, audit_info);
 240        if (ret_val != 0)
 241                goto add_failure;
 242
 243        return 0;
 244
 245add_failure:
 246        if (cipsov4)
 247                cipso_v4_doi_putdef(cipsov4);
 248        if (entry)
 249                kfree(entry->domain);
 250        kfree(addrmap);
 251        kfree(entry);
 252        return ret_val;
 253}
 254
 255/**
 256 * netlbl_mgmt_listentry - List a NetLabel/LSM domain map entry
 257 * @skb: the NETLINK buffer
 258 * @entry: the map entry
 259 *
 260 * Description:
 261 * This function is a helper function used by the LISTALL and LISTDEF command
 262 * handlers.  The caller is responsible for ensuring that the RCU read lock
 263 * is held.  Returns zero on success, negative values on failure.
 264 *
 265 */
 266static int netlbl_mgmt_listentry(struct sk_buff *skb,
 267                                 struct netlbl_dom_map *entry)
 268{
 269        int ret_val = 0;
 270        struct nlattr *nla_a;
 271        struct nlattr *nla_b;
 272        struct netlbl_af4list *iter4;
 273#if IS_ENABLED(CONFIG_IPV6)
 274        struct netlbl_af6list *iter6;
 275#endif
 276
 277        if (entry->domain != NULL) {
 278                ret_val = nla_put_string(skb,
 279                                         NLBL_MGMT_A_DOMAIN, entry->domain);
 280                if (ret_val != 0)
 281                        return ret_val;
 282        }
 283
 284        switch (entry->def.type) {
 285        case NETLBL_NLTYPE_ADDRSELECT:
 286                nla_a = nla_nest_start(skb, NLBL_MGMT_A_SELECTORLIST);
 287                if (nla_a == NULL)
 288                        return -ENOMEM;
 289
 290                netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) {
 291                        struct netlbl_domaddr4_map *map4;
 292                        struct in_addr addr_struct;
 293
 294                        nla_b = nla_nest_start(skb, NLBL_MGMT_A_ADDRSELECTOR);
 295                        if (nla_b == NULL)
 296                                return -ENOMEM;
 297
 298                        addr_struct.s_addr = iter4->addr;
 299                        ret_val = nla_put(skb, NLBL_MGMT_A_IPV4ADDR,
 300                                          sizeof(struct in_addr),
 301                                          &addr_struct);
 302                        if (ret_val != 0)
 303                                return ret_val;
 304                        addr_struct.s_addr = iter4->mask;
 305                        ret_val = nla_put(skb, NLBL_MGMT_A_IPV4MASK,
 306                                          sizeof(struct in_addr),
 307                                          &addr_struct);
 308                        if (ret_val != 0)
 309                                return ret_val;
 310                        map4 = netlbl_domhsh_addr4_entry(iter4);
 311                        ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL,
 312                                              map4->def.type);
 313                        if (ret_val != 0)
 314                                return ret_val;
 315                        switch (map4->def.type) {
 316                        case NETLBL_NLTYPE_CIPSOV4:
 317                                ret_val = nla_put_u32(skb, NLBL_MGMT_A_CV4DOI,
 318                                                      map4->def.cipso->doi);
 319                                if (ret_val != 0)
 320                                        return ret_val;
 321                                break;
 322                        }
 323
 324                        nla_nest_end(skb, nla_b);
 325                }
 326#if IS_ENABLED(CONFIG_IPV6)
 327                netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) {
 328                        struct netlbl_domaddr6_map *map6;
 329
 330                        nla_b = nla_nest_start(skb, NLBL_MGMT_A_ADDRSELECTOR);
 331                        if (nla_b == NULL)
 332                                return -ENOMEM;
 333
 334                        ret_val = nla_put(skb, NLBL_MGMT_A_IPV6ADDR,
 335                                          sizeof(struct in6_addr),
 336                                          &iter6->addr);
 337                        if (ret_val != 0)
 338                                return ret_val;
 339                        ret_val = nla_put(skb, NLBL_MGMT_A_IPV6MASK,
 340                                          sizeof(struct in6_addr),
 341                                          &iter6->mask);
 342                        if (ret_val != 0)
 343                                return ret_val;
 344                        map6 = netlbl_domhsh_addr6_entry(iter6);
 345                        ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL,
 346                                              map6->def.type);
 347                        if (ret_val != 0)
 348                                return ret_val;
 349
 350                        nla_nest_end(skb, nla_b);
 351                }
 352#endif /* IPv6 */
 353
 354                nla_nest_end(skb, nla_a);
 355                break;
 356        case NETLBL_NLTYPE_UNLABELED:
 357                ret_val = nla_put_u32(skb,NLBL_MGMT_A_PROTOCOL,entry->def.type);
 358                break;
 359        case NETLBL_NLTYPE_CIPSOV4:
 360                ret_val = nla_put_u32(skb,NLBL_MGMT_A_PROTOCOL,entry->def.type);
 361                if (ret_val != 0)
 362                        return ret_val;
 363                ret_val = nla_put_u32(skb, NLBL_MGMT_A_CV4DOI,
 364                                      entry->def.cipso->doi);
 365                break;
 366        }
 367
 368        return ret_val;
 369}
 370
 371/*
 372 * NetLabel Command Handlers
 373 */
 374
 375/**
 376 * netlbl_mgmt_add - Handle an ADD message
 377 * @skb: the NETLINK buffer
 378 * @info: the Generic NETLINK info block
 379 *
 380 * Description:
 381 * Process a user generated ADD message and add the domains from the message
 382 * to the hash table.  See netlabel.h for a description of the message format.
 383 * Returns zero on success, negative values on failure.
 384 *
 385 */
 386static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
 387{
 388        struct netlbl_audit audit_info;
 389
 390        if ((!info->attrs[NLBL_MGMT_A_DOMAIN]) ||
 391            (!info->attrs[NLBL_MGMT_A_PROTOCOL]) ||
 392            (info->attrs[NLBL_MGMT_A_IPV4ADDR] &&
 393             info->attrs[NLBL_MGMT_A_IPV6ADDR]) ||
 394            (info->attrs[NLBL_MGMT_A_IPV4MASK] &&
 395             info->attrs[NLBL_MGMT_A_IPV6MASK]) ||
 396            ((info->attrs[NLBL_MGMT_A_IPV4ADDR] != NULL) ^
 397             (info->attrs[NLBL_MGMT_A_IPV4MASK] != NULL)) ||
 398            ((info->attrs[NLBL_MGMT_A_IPV6ADDR] != NULL) ^
 399             (info->attrs[NLBL_MGMT_A_IPV6MASK] != NULL)))
 400                return -EINVAL;
 401
 402        netlbl_netlink_auditinfo(skb, &audit_info);
 403
 404        return netlbl_mgmt_add_common(info, &audit_info);
 405}
 406
 407/**
 408 * netlbl_mgmt_remove - Handle a REMOVE message
 409 * @skb: the NETLINK buffer
 410 * @info: the Generic NETLINK info block
 411 *
 412 * Description:
 413 * Process a user generated REMOVE message and remove the specified domain
 414 * mappings.  Returns zero on success, negative values on failure.
 415 *
 416 */
 417static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
 418{
 419        char *domain;
 420        struct netlbl_audit audit_info;
 421
 422        if (!info->attrs[NLBL_MGMT_A_DOMAIN])
 423                return -EINVAL;
 424
 425        netlbl_netlink_auditinfo(skb, &audit_info);
 426
 427        domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
 428        return netlbl_domhsh_remove(domain, &audit_info);
 429}
 430
 431/**
 432 * netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
 433 * @entry: the domain mapping hash table entry
 434 * @arg: the netlbl_domhsh_walk_arg structure
 435 *
 436 * Description:
 437 * This function is designed to be used as a callback to the
 438 * netlbl_domhsh_walk() function for use in generating a response for a LISTALL
 439 * message.  Returns the size of the message on success, negative values on
 440 * failure.
 441 *
 442 */
 443static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg)
 444{
 445        int ret_val = -ENOMEM;
 446        struct netlbl_domhsh_walk_arg *cb_arg = arg;
 447        void *data;
 448
 449        data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
 450                           cb_arg->seq, &netlbl_mgmt_gnl_family,
 451                           NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
 452        if (data == NULL)
 453                goto listall_cb_failure;
 454
 455        ret_val = netlbl_mgmt_listentry(cb_arg->skb, entry);
 456        if (ret_val != 0)
 457                goto listall_cb_failure;
 458
 459        cb_arg->seq++;
 460        return genlmsg_end(cb_arg->skb, data);
 461
 462listall_cb_failure:
 463        genlmsg_cancel(cb_arg->skb, data);
 464        return ret_val;
 465}
 466
 467/**
 468 * netlbl_mgmt_listall - Handle a LISTALL message
 469 * @skb: the NETLINK buffer
 470 * @cb: the NETLINK callback
 471 *
 472 * Description:
 473 * Process a user generated LISTALL message and dumps the domain hash table in
 474 * a form suitable for use in a kernel generated LISTALL message.  Returns zero
 475 * on success, negative values on failure.
 476 *
 477 */
 478static int netlbl_mgmt_listall(struct sk_buff *skb,
 479                               struct netlink_callback *cb)
 480{
 481        struct netlbl_domhsh_walk_arg cb_arg;
 482        u32 skip_bkt = cb->args[0];
 483        u32 skip_chain = cb->args[1];
 484
 485        cb_arg.nl_cb = cb;
 486        cb_arg.skb = skb;
 487        cb_arg.seq = cb->nlh->nlmsg_seq;
 488
 489        netlbl_domhsh_walk(&skip_bkt,
 490                           &skip_chain,
 491                           netlbl_mgmt_listall_cb,
 492                           &cb_arg);
 493
 494        cb->args[0] = skip_bkt;
 495        cb->args[1] = skip_chain;
 496        return skb->len;
 497}
 498
 499/**
 500 * netlbl_mgmt_adddef - Handle an ADDDEF message
 501 * @skb: the NETLINK buffer
 502 * @info: the Generic NETLINK info block
 503 *
 504 * Description:
 505 * Process a user generated ADDDEF message and respond accordingly.  Returns
 506 * zero on success, negative values on failure.
 507 *
 508 */
 509static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
 510{
 511        struct netlbl_audit audit_info;
 512
 513        if ((!info->attrs[NLBL_MGMT_A_PROTOCOL]) ||
 514            (info->attrs[NLBL_MGMT_A_IPV4ADDR] &&
 515             info->attrs[NLBL_MGMT_A_IPV6ADDR]) ||
 516            (info->attrs[NLBL_MGMT_A_IPV4MASK] &&
 517             info->attrs[NLBL_MGMT_A_IPV6MASK]) ||
 518            ((info->attrs[NLBL_MGMT_A_IPV4ADDR] != NULL) ^
 519             (info->attrs[NLBL_MGMT_A_IPV4MASK] != NULL)) ||
 520            ((info->attrs[NLBL_MGMT_A_IPV6ADDR] != NULL) ^
 521             (info->attrs[NLBL_MGMT_A_IPV6MASK] != NULL)))
 522                return -EINVAL;
 523
 524        netlbl_netlink_auditinfo(skb, &audit_info);
 525
 526        return netlbl_mgmt_add_common(info, &audit_info);
 527}
 528
 529/**
 530 * netlbl_mgmt_removedef - Handle a REMOVEDEF message
 531 * @skb: the NETLINK buffer
 532 * @info: the Generic NETLINK info block
 533 *
 534 * Description:
 535 * Process a user generated REMOVEDEF message and remove the default domain
 536 * mapping.  Returns zero on success, negative values on failure.
 537 *
 538 */
 539static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
 540{
 541        struct netlbl_audit audit_info;
 542
 543        netlbl_netlink_auditinfo(skb, &audit_info);
 544
 545        return netlbl_domhsh_remove_default(&audit_info);
 546}
 547
 548/**
 549 * netlbl_mgmt_listdef - Handle a LISTDEF message
 550 * @skb: the NETLINK buffer
 551 * @info: the Generic NETLINK info block
 552 *
 553 * Description:
 554 * Process a user generated LISTDEF message and dumps the default domain
 555 * mapping in a form suitable for use in a kernel generated LISTDEF message.
 556 * Returns zero on success, negative values on failure.
 557 *
 558 */
 559static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info)
 560{
 561        int ret_val = -ENOMEM;
 562        struct sk_buff *ans_skb = NULL;
 563        void *data;
 564        struct netlbl_dom_map *entry;
 565
 566        ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 567        if (ans_skb == NULL)
 568                return -ENOMEM;
 569        data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
 570                                 0, NLBL_MGMT_C_LISTDEF);
 571        if (data == NULL)
 572                goto listdef_failure;
 573
 574        rcu_read_lock();
 575        entry = netlbl_domhsh_getentry(NULL);
 576        if (entry == NULL) {
 577                ret_val = -ENOENT;
 578                goto listdef_failure_lock;
 579        }
 580        ret_val = netlbl_mgmt_listentry(ans_skb, entry);
 581        rcu_read_unlock();
 582        if (ret_val != 0)
 583                goto listdef_failure;
 584
 585        genlmsg_end(ans_skb, data);
 586        return genlmsg_reply(ans_skb, info);
 587
 588listdef_failure_lock:
 589        rcu_read_unlock();
 590listdef_failure:
 591        kfree_skb(ans_skb);
 592        return ret_val;
 593}
 594
 595/**
 596 * netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
 597 * @skb: the skb to write to
 598 * @cb: the NETLINK callback
 599 * @protocol: the NetLabel protocol to use in the message
 600 *
 601 * Description:
 602 * This function is to be used in conjunction with netlbl_mgmt_protocols() to
 603 * answer a application's PROTOCOLS message.  Returns the size of the message
 604 * on success, negative values on failure.
 605 *
 606 */
 607static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
 608                                    struct netlink_callback *cb,
 609                                    u32 protocol)
 610{
 611        int ret_val = -ENOMEM;
 612        void *data;
 613
 614        data = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 615                           &netlbl_mgmt_gnl_family, NLM_F_MULTI,
 616                           NLBL_MGMT_C_PROTOCOLS);
 617        if (data == NULL)
 618                goto protocols_cb_failure;
 619
 620        ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
 621        if (ret_val != 0)
 622                goto protocols_cb_failure;
 623
 624        return genlmsg_end(skb, data);
 625
 626protocols_cb_failure:
 627        genlmsg_cancel(skb, data);
 628        return ret_val;
 629}
 630
 631/**
 632 * netlbl_mgmt_protocols - Handle a PROTOCOLS message
 633 * @skb: the NETLINK buffer
 634 * @cb: the NETLINK callback
 635 *
 636 * Description:
 637 * Process a user generated PROTOCOLS message and respond accordingly.
 638 *
 639 */
 640static int netlbl_mgmt_protocols(struct sk_buff *skb,
 641                                 struct netlink_callback *cb)
 642{
 643        u32 protos_sent = cb->args[0];
 644
 645        if (protos_sent == 0) {
 646                if (netlbl_mgmt_protocols_cb(skb,
 647                                             cb,
 648                                             NETLBL_NLTYPE_UNLABELED) < 0)
 649                        goto protocols_return;
 650                protos_sent++;
 651        }
 652        if (protos_sent == 1) {
 653                if (netlbl_mgmt_protocols_cb(skb,
 654                                             cb,
 655                                             NETLBL_NLTYPE_CIPSOV4) < 0)
 656                        goto protocols_return;
 657                protos_sent++;
 658        }
 659
 660protocols_return:
 661        cb->args[0] = protos_sent;
 662        return skb->len;
 663}
 664
 665/**
 666 * netlbl_mgmt_version - Handle a VERSION message
 667 * @skb: the NETLINK buffer
 668 * @info: the Generic NETLINK info block
 669 *
 670 * Description:
 671 * Process a user generated VERSION message and respond accordingly.  Returns
 672 * zero on success, negative values on failure.
 673 *
 674 */
 675static int netlbl_mgmt_version(struct sk_buff *skb, struct genl_info *info)
 676{
 677        int ret_val = -ENOMEM;
 678        struct sk_buff *ans_skb = NULL;
 679        void *data;
 680
 681        ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 682        if (ans_skb == NULL)
 683                return -ENOMEM;
 684        data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
 685                                 0, NLBL_MGMT_C_VERSION);
 686        if (data == NULL)
 687                goto version_failure;
 688
 689        ret_val = nla_put_u32(ans_skb,
 690                              NLBL_MGMT_A_VERSION,
 691                              NETLBL_PROTO_VERSION);
 692        if (ret_val != 0)
 693                goto version_failure;
 694
 695        genlmsg_end(ans_skb, data);
 696        return genlmsg_reply(ans_skb, info);
 697
 698version_failure:
 699        kfree_skb(ans_skb);
 700        return ret_val;
 701}
 702
 703
 704/*
 705 * NetLabel Generic NETLINK Command Definitions
 706 */
 707
 708static struct genl_ops netlbl_mgmt_genl_ops[] = {
 709        {
 710        .cmd = NLBL_MGMT_C_ADD,
 711        .flags = GENL_ADMIN_PERM,
 712        .policy = netlbl_mgmt_genl_policy,
 713        .doit = netlbl_mgmt_add,
 714        .dumpit = NULL,
 715        },
 716        {
 717        .cmd = NLBL_MGMT_C_REMOVE,
 718        .flags = GENL_ADMIN_PERM,
 719        .policy = netlbl_mgmt_genl_policy,
 720        .doit = netlbl_mgmt_remove,
 721        .dumpit = NULL,
 722        },
 723        {
 724        .cmd = NLBL_MGMT_C_LISTALL,
 725        .flags = 0,
 726        .policy = netlbl_mgmt_genl_policy,
 727        .doit = NULL,
 728        .dumpit = netlbl_mgmt_listall,
 729        },
 730        {
 731        .cmd = NLBL_MGMT_C_ADDDEF,
 732        .flags = GENL_ADMIN_PERM,
 733        .policy = netlbl_mgmt_genl_policy,
 734        .doit = netlbl_mgmt_adddef,
 735        .dumpit = NULL,
 736        },
 737        {
 738        .cmd = NLBL_MGMT_C_REMOVEDEF,
 739        .flags = GENL_ADMIN_PERM,
 740        .policy = netlbl_mgmt_genl_policy,
 741        .doit = netlbl_mgmt_removedef,
 742        .dumpit = NULL,
 743        },
 744        {
 745        .cmd = NLBL_MGMT_C_LISTDEF,
 746        .flags = 0,
 747        .policy = netlbl_mgmt_genl_policy,
 748        .doit = netlbl_mgmt_listdef,
 749        .dumpit = NULL,
 750        },
 751        {
 752        .cmd = NLBL_MGMT_C_PROTOCOLS,
 753        .flags = 0,
 754        .policy = netlbl_mgmt_genl_policy,
 755        .doit = NULL,
 756        .dumpit = netlbl_mgmt_protocols,
 757        },
 758        {
 759        .cmd = NLBL_MGMT_C_VERSION,
 760        .flags = 0,
 761        .policy = netlbl_mgmt_genl_policy,
 762        .doit = netlbl_mgmt_version,
 763        .dumpit = NULL,
 764        },
 765};
 766
 767/*
 768 * NetLabel Generic NETLINK Protocol Functions
 769 */
 770
 771/**
 772 * netlbl_mgmt_genl_init - Register the NetLabel management component
 773 *
 774 * Description:
 775 * Register the NetLabel management component with the Generic NETLINK
 776 * mechanism.  Returns zero on success, negative values on failure.
 777 *
 778 */
 779int __init netlbl_mgmt_genl_init(void)
 780{
 781        return genl_register_family_with_ops(&netlbl_mgmt_gnl_family,
 782                netlbl_mgmt_genl_ops, ARRAY_SIZE(netlbl_mgmt_genl_ops));
 783}
 784