net/batman-adv/netlink.c

   1 /* Copyright (C) 2016 B.A.T.M.A.N. contributors:
   2  *
   3  * Matthias Schiffer
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "netlink.h"
  19 #include "main.h"
  20
  21 #include <linux/errno.h>
  22 #include <linux/fs.h>
  23 #include <linux/genetlink.h>
  24 #include <linux/if_ether.h>
  25 #include <linux/init.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/netlink.h>
  28 #include <linux/printk.h>
  29 #include <linux/rculist.h>
  30 #include <linux/rcupdate.h>
  31 #include <linux/skbuff.h>
  32 #include <linux/stddef.h>
  33 #include <linux/types.h>
  34 #include <net/genetlink.h>
  35 #include <net/netlink.h>
  36 #include <net/sock.h>
  37 #include <uapi/linux/batman_adv.h>
  38
  39 #include "bat_algo.h"
  40 #include "hard-interface.h"
  41 #include "soft-interface.h"
  42 #include "tp_meter.h"
  43 #include "translation-table.h"
  44
  45 struct genl_family batadv_netlink_family = {
  46         .id = GENL_ID_GENERATE,
  47         .hdrsize = 0,
  48         .name = BATADV_NL_NAME,
  49         .version = 1,
  50         .maxattr = BATADV_ATTR_MAX,
  51 };
  52
  53 /* multicast groups */
  54 enum batadv_netlink_multicast_groups {
  55         BATADV_NL_MCGRP_TPMETER,
  56 };
  57
  58 static struct genl_multicast_group batadv_netlink_mcgrps[] = {
  59         [BATADV_NL_MCGRP_TPMETER] = { .name = BATADV_NL_MCAST_GROUP_TPMETER },
  60 };
  61
  62 static struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
  63         [BATADV_ATTR_VERSION]           = { .type = NLA_STRING },
  64         [BATADV_ATTR_ALGO_NAME]         = { .type = NLA_STRING },
  65         [BATADV_ATTR_MESH_IFINDEX]      = { .type = NLA_U32 },
  66         [BATADV_ATTR_MESH_IFNAME]       = { .type = NLA_STRING },
  67         [BATADV_ATTR_MESH_ADDRESS]      = { .len = ETH_ALEN },
  68         [BATADV_ATTR_HARD_IFINDEX]      = { .type = NLA_U32 },
  69         [BATADV_ATTR_HARD_IFNAME]       = { .type = NLA_STRING },
  70         [BATADV_ATTR_HARD_ADDRESS]      = { .len = ETH_ALEN },
  71         [BATADV_ATTR_ORIG_ADDRESS]      = { .len = ETH_ALEN },
  72         [BATADV_ATTR_TPMETER_RESULT]    = { .type = NLA_U8 },
  73         [BATADV_ATTR_TPMETER_TEST_TIME] = { .type = NLA_U32 },
  74         [BATADV_ATTR_TPMETER_BYTES]     = { .type = NLA_U64 },
  75         [BATADV_ATTR_TPMETER_COOKIE]    = { .type = NLA_U32 },
  76         [BATADV_ATTR_ACTIVE]            = { .type = NLA_FLAG },
  77         [BATADV_ATTR_TT_ADDRESS]        = { .len = ETH_ALEN },
  78         [BATADV_ATTR_TT_TTVN]           = { .type = NLA_U8 },
  79         [BATADV_ATTR_TT_LAST_TTVN]      = { .type = NLA_U8 },
  80         [BATADV_ATTR_TT_CRC32]          = { .type = NLA_U32 },
  81         [BATADV_ATTR_TT_VID]            = { .type = NLA_U16 },
  82         [BATADV_ATTR_TT_FLAGS]          = { .type = NLA_U32 },
  83         [BATADV_ATTR_FLAG_BEST]         = { .type = NLA_FLAG },
  84         [BATADV_ATTR_LAST_SEEN_MSECS]   = { .type = NLA_U32 },
  85 };
  86
  87 /**
  88  * batadv_netlink_get_ifindex - Extract an interface index from a message
  89  * @nlh: Message header
  90  * @attrtype: Attribute which holds an interface index
  91  *
  92  * Return: interface index, or 0.
  93  */
  94 int
  95 batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype)
  96 {
  97         struct nlattr *attr = nlmsg_find_attr(nlh, GENL_HDRLEN, attrtype);
  98
  99         return attr ? nla_get_u32(attr) : 0;
 100 }
 101
 102 /**
 103  * batadv_netlink_mesh_info_put - fill in generic information about mesh
 104  *  interface
 105  * @msg: netlink message to be sent back
 106  * @soft_iface: interface for which the data should be taken
 107  *
 108  * Return: 0 on success, < 0 on error
 109  */
 110 static int
 111 batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface)
 112 {
 113         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
 114         struct batadv_hard_iface *primary_if = NULL;
 115         struct net_device *hard_iface;
 116         int ret = -ENOBUFS;
 117
 118         if (nla_put_string(msg, BATADV_ATTR_VERSION, BATADV_SOURCE_VERSION) ||
 119             nla_put_string(msg, BATADV_ATTR_ALGO_NAME,
 120                            bat_priv->algo_ops->name) ||
 121             nla_put_u32(msg, BATADV_ATTR_MESH_IFINDEX, soft_iface->ifindex) ||
 122             nla_put_string(msg, BATADV_ATTR_MESH_IFNAME, soft_iface->name) ||
 123             nla_put(msg, BATADV_ATTR_MESH_ADDRESS, ETH_ALEN,
 124                     soft_iface->dev_addr))
 125                 goto out;
 126
 127         primary_if = batadv_primary_if_get_selected(bat_priv);
 128         if (primary_if && primary_if->if_status == BATADV_IF_ACTIVE) {
 129                 hard_iface = primary_if->net_dev;
 130
 131                 if (nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
 132                                 hard_iface->ifindex) ||
 133                     nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
 134                                    hard_iface->name) ||
 135                     nla_put(msg, BATADV_ATTR_HARD_ADDRESS, ETH_ALEN,
 136                             hard_iface->dev_addr))
 137                         goto out;
 138         }
 139
 140         ret = 0;
 141
 142  out:
 143         if (primary_if)
 144                 batadv_hardif_put(primary_if);
 145
 146         return ret;
 147 }
 148
 149 /**
 150  * batadv_netlink_get_mesh_info - handle incoming BATADV_CMD_GET_MESH_INFO
 151  *  netlink request
 152  * @skb: received netlink message
 153  * @info: receiver information
 154  *
 155  * Return: 0 on success, < 0 on error
 156  */
 157 static int
 158 batadv_netlink_get_mesh_info(struct sk_buff *skb, struct genl_info *info)
 159 {
 160         struct net *net = genl_info_net(info);
 161         struct net_device *soft_iface;
 162         struct sk_buff *msg = NULL;
 163         void *msg_head;
 164         int ifindex;
 165         int ret;
 166
 167         if (!info->attrs[BATADV_ATTR_MESH_IFINDEX])
 168                 return -EINVAL;
 169
 170         ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]);
 171         if (!ifindex)
 172                 return -EINVAL;
 173
 174         soft_iface = dev_get_by_index(net, ifindex);
 175         if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
 176                 ret = -ENODEV;
 177                 goto out;
 178         }
 179
 180         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 181         if (!msg) {
 182                 ret = -ENOMEM;
 183                 goto out;
 184         }
 185
 186         msg_head = genlmsg_put(msg, info->snd_portid, info->snd_seq,
 187                                &batadv_netlink_family, 0,
 188                                BATADV_CMD_GET_MESH_INFO);
 189         if (!msg_head) {
 190                 ret = -ENOBUFS;
 191                 goto out;
 192         }
 193
 194         ret = batadv_netlink_mesh_info_put(msg, soft_iface);
 195
 196  out:
 197         if (soft_iface)
 198                 dev_put(soft_iface);
 199
 200         if (ret) {
 201                 if (msg)
 202                         nlmsg_free(msg);
 203                 return ret;
 204         }
 205
 206         genlmsg_end(msg, msg_head);
 207         return genlmsg_reply(msg, info);
 208 }
 209
 210 /**
 211  * batadv_netlink_tp_meter_put - Fill information of started tp_meter session
 212  * @msg: netlink message to be sent back
 213  * @cookie: tp meter session cookie
 214  *
 215  *  Return: 0 on success, < 0 on error
 216  */
 217 static int
 218 batadv_netlink_tp_meter_put(struct sk_buff *msg, u32 cookie)
 219 {
 220         if (nla_put_u32(msg, BATADV_ATTR_TPMETER_COOKIE, cookie))
 221                 return -ENOBUFS;
 222
 223         return 0;
 224 }
 225
 226 /**
 227  * batadv_netlink_tpmeter_notify - send tp_meter result via netlink to client
 228  * @bat_priv: the bat priv with all the soft interface information
 229  * @dst: destination of tp_meter session
 230  * @result: reason for tp meter session stop
 231  * @test_time: total time ot the tp_meter session
 232  * @total_bytes: bytes acked to the receiver
 233  * @cookie: cookie of tp_meter session
 234  *
 235  * Return: 0 on success, < 0 on error
 236  */
 237 int batadv_netlink_tpmeter_notify(struct batadv_priv *bat_priv, const u8 *dst,
 238                                   u8 result, u32 test_time, u64 total_bytes,
 239                                   u32 cookie)
 240 {
 241         struct sk_buff *msg;
 242         void *hdr;
 243         int ret;
 244
 245         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 246         if (!msg)
 247                 return -ENOMEM;
 248
 249         hdr = genlmsg_put(msg, 0, 0, &batadv_netlink_family, 0,
 250                           BATADV_CMD_TP_METER);
 251         if (!hdr) {
 252                 ret = -ENOBUFS;
 253                 goto err_genlmsg;
 254         }
 255
 256         if (nla_put_u32(msg, BATADV_ATTR_TPMETER_COOKIE, cookie))
 257                 goto nla_put_failure;
 258
 259         if (nla_put_u32(msg, BATADV_ATTR_TPMETER_TEST_TIME, test_time))
 260                 goto nla_put_failure;
 261
 262         if (nla_put_u64_64bit(msg, BATADV_ATTR_TPMETER_BYTES, total_bytes,
 263                               BATADV_ATTR_PAD))
 264                 goto nla_put_failure;
 265
 266         if (nla_put_u8(msg, BATADV_ATTR_TPMETER_RESULT, result))
 267                 goto nla_put_failure;
 268
 269         if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN, dst))
 270                 goto nla_put_failure;
 271
 272         genlmsg_end(msg, hdr);
 273
 274         genlmsg_multicast_netns(&batadv_netlink_family,
 275                                 dev_net(bat_priv->soft_iface), msg, 0,
 276                                 BATADV_NL_MCGRP_TPMETER, GFP_KERNEL);
 277
 278         return 0;
 279
 280 nla_put_failure:
 281         genlmsg_cancel(msg, hdr);
 282         ret = -EMSGSIZE;
 283
 284 err_genlmsg:
 285         nlmsg_free(msg);
 286         return ret;
 287 }
 288
 289 /**
 290  * batadv_netlink_tp_meter_start - Start a new tp_meter session
 291  * @skb: received netlink message
 292  * @info: receiver information
 293  *
 294  * Return: 0 on success, < 0 on error
 295  */
 296 static int
 297 batadv_netlink_tp_meter_start(struct sk_buff *skb, struct genl_info *info)
 298 {
 299         struct net *net = genl_info_net(info);
 300         struct net_device *soft_iface;
 301         struct batadv_priv *bat_priv;
 302         struct sk_buff *msg = NULL;
 303         u32 test_length;
 304         void *msg_head;
 305         int ifindex;
 306         u32 cookie;
 307         u8 *dst;
 308         int ret;
 309
 310         if (!info->attrs[BATADV_ATTR_MESH_IFINDEX])
 311                 return -EINVAL;
 312
 313         if (!info->attrs[BATADV_ATTR_ORIG_ADDRESS])
 314                 return -EINVAL;
 315
 316         if (!info->attrs[BATADV_ATTR_TPMETER_TEST_TIME])
 317                 return -EINVAL;
 318
 319         ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]);
 320         if (!ifindex)
 321                 return -EINVAL;
 322
 323         dst = nla_data(info->attrs[BATADV_ATTR_ORIG_ADDRESS]);
 324
 325         test_length = nla_get_u32(info->attrs[BATADV_ATTR_TPMETER_TEST_TIME]);
 326
 327         soft_iface = dev_get_by_index(net, ifindex);
 328         if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
 329                 ret = -ENODEV;
 330                 goto out;
 331         }
 332
 333         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 334         if (!msg) {
 335                 ret = -ENOMEM;
 336                 goto out;
 337         }
 338
 339         msg_head = genlmsg_put(msg, info->snd_portid, info->snd_seq,
 340                                &batadv_netlink_family, 0,
 341                                BATADV_CMD_TP_METER);
 342         if (!msg_head) {
 343                 ret = -ENOBUFS;
 344                 goto out;
 345         }
 346
 347         bat_priv = netdev_priv(soft_iface);
 348         batadv_tp_start(bat_priv, dst, test_length, &cookie);
 349
 350         ret = batadv_netlink_tp_meter_put(msg, cookie);
 351
 352  out:
 353         if (soft_iface)
 354                 dev_put(soft_iface);
 355
 356         if (ret) {
 357                 if (msg)
 358                         nlmsg_free(msg);
 359                 return ret;
 360         }
 361
 362         genlmsg_end(msg, msg_head);
 363         return genlmsg_reply(msg, info);
 364 }
 365
 366 /**
 367  * batadv_netlink_tp_meter_start - Cancel a running tp_meter session
 368  * @skb: received netlink message
 369  * @info: receiver information
 370  *
 371  * Return: 0 on success, < 0 on error
 372  */
 373 static int
 374 batadv_netlink_tp_meter_cancel(struct sk_buff *skb, struct genl_info *info)
 375 {
 376         struct net *net = genl_info_net(info);
 377         struct net_device *soft_iface;
 378         struct batadv_priv *bat_priv;
 379         int ifindex;
 380         u8 *dst;
 381         int ret = 0;
 382
 383         if (!info->attrs[BATADV_ATTR_MESH_IFINDEX])
 384                 return -EINVAL;
 385
 386         if (!info->attrs[BATADV_ATTR_ORIG_ADDRESS])
 387                 return -EINVAL;
 388
 389         ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]);
 390         if (!ifindex)
 391                 return -EINVAL;
 392
 393         dst = nla_data(info->attrs[BATADV_ATTR_ORIG_ADDRESS]);
 394
 395         soft_iface = dev_get_by_index(net, ifindex);
 396         if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
 397                 ret = -ENODEV;
 398                 goto out;
 399         }
 400
 401         bat_priv = netdev_priv(soft_iface);
 402         batadv_tp_stop(bat_priv, dst, BATADV_TP_REASON_CANCEL);
 403
 404 out:
 405         if (soft_iface)
 406                 dev_put(soft_iface);
 407
 408         return ret;
 409 }
 410
 411 /**
 412  * batadv_netlink_dump_hardif_entry - Dump one hard interface into a message
 413  * @msg: Netlink message to dump into
 414  * @portid: Port making netlink request
 415  * @seq: Sequence number of netlink message
 416  * @hard_iface: Hard interface to dump
 417  *
 418  * Return: error code, or 0 on success
 419  */
 420 static int
 421 batadv_netlink_dump_hardif_entry(struct sk_buff *msg, u32 portid, u32 seq,
 422                                  struct batadv_hard_iface *hard_iface)
 423 {
 424         struct net_device *net_dev = hard_iface->net_dev;
 425         void *hdr;
 426
 427         hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, NLM_F_MULTI,
 428                           BATADV_CMD_GET_HARDIFS);
 429         if (!hdr)
 430                 return -EMSGSIZE;
 431
 432         if (nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
 433                         net_dev->ifindex) ||
 434             nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
 435                            net_dev->name) ||
 436             nla_put(msg, BATADV_ATTR_HARD_ADDRESS, ETH_ALEN,
 437                     net_dev->dev_addr))
 438                 goto nla_put_failure;
 439
 440         if (hard_iface->if_status == BATADV_IF_ACTIVE) {
 441                 if (nla_put_flag(msg, BATADV_ATTR_ACTIVE))
 442                         goto nla_put_failure;
 443         }
 444
 445         genlmsg_end(msg, hdr);
 446         return 0;
 447
 448  nla_put_failure:
 449         genlmsg_cancel(msg, hdr);
 450         return -EMSGSIZE;
 451 }
 452
 453 /**
 454  * batadv_netlink_dump_hardifs - Dump all hard interface into a messages
 455  * @msg: Netlink message to dump into
 456  * @cb: Parameters from query
 457  *
 458  * Return: error code, or length of reply message on success
 459  */
 460 static int
 461 batadv_netlink_dump_hardifs(struct sk_buff *msg, struct netlink_callback *cb)
 462 {
 463         struct net *net = sock_net(cb->skb->sk);
 464         struct net_device *soft_iface;
 465         struct batadv_hard_iface *hard_iface;
 466         int ifindex;
 467         int portid = NETLINK_CB(cb->skb).portid;
 468         int seq = cb->nlh->nlmsg_seq;
 469         int skip = cb->args[0];
 470         int i = 0;
 471
 472         ifindex = batadv_netlink_get_ifindex(cb->nlh,
 473                                              BATADV_ATTR_MESH_IFINDEX);
 474         if (!ifindex)
 475                 return -EINVAL;
 476
 477         soft_iface = dev_get_by_index(net, ifindex);
 478         if (!soft_iface)
 479                 return -ENODEV;
 480
 481         if (!batadv_softif_is_valid(soft_iface)) {
 482                 dev_put(soft_iface);
 483                 return -ENODEV;
 484         }
 485
 486         rcu_read_lock();
 487
 488         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 489                 if (hard_iface->soft_iface != soft_iface)
 490                         continue;
 491
 492                 if (i++ < skip)
 493                         continue;
 494
 495                 if (batadv_netlink_dump_hardif_entry(msg, portid, seq,
 496                                                      hard_iface)) {
 497                         i--;
 498                         break;
 499                 }
 500         }
 501
 502         rcu_read_unlock();
 503
 504         dev_put(soft_iface);
 505
 506         cb->args[0] = i;
 507
 508         return msg->len;
 509 }
 510
 511 static struct genl_ops batadv_netlink_ops[] = {
 512         {
 513                 .cmd = BATADV_CMD_GET_MESH_INFO,
 514                 .flags = GENL_ADMIN_PERM,
 515                 .policy = batadv_netlink_policy,
 516                 .doit = batadv_netlink_get_mesh_info,
 517         },
 518         {
 519                 .cmd = BATADV_CMD_TP_METER,
 520                 .flags = GENL_ADMIN_PERM,
 521                 .policy = batadv_netlink_policy,
 522                 .doit = batadv_netlink_tp_meter_start,
 523         },
 524         {
 525                 .cmd = BATADV_CMD_TP_METER_CANCEL,
 526                 .flags = GENL_ADMIN_PERM,
 527                 .policy = batadv_netlink_policy,
 528                 .doit = batadv_netlink_tp_meter_cancel,
 529         },
 530         {
 531                 .cmd = BATADV_CMD_GET_ROUTING_ALGOS,
 532                 .flags = GENL_ADMIN_PERM,
 533                 .policy = batadv_netlink_policy,
 534                 .dumpit = batadv_algo_dump,
 535         },
 536         {
 537                 .cmd = BATADV_CMD_GET_HARDIFS,
 538                 .flags = GENL_ADMIN_PERM,
 539                 .policy = batadv_netlink_policy,
 540                 .dumpit = batadv_netlink_dump_hardifs,
 541         },
 542         {
 543                 .cmd = BATADV_CMD_GET_TRANSTABLE_LOCAL,
 544                 .flags = GENL_ADMIN_PERM,
 545                 .policy = batadv_netlink_policy,
 546                 .dumpit = batadv_tt_local_dump,
 547         },
 548         {
 549                 .cmd = BATADV_CMD_GET_TRANSTABLE_GLOBAL,
 550                 .flags = GENL_ADMIN_PERM,
 551                 .policy = batadv_netlink_policy,
 552                 .dumpit = batadv_tt_global_dump,
 553         },
 554 };
 555
 556 /**
 557  * batadv_netlink_register - register batadv genl netlink family
 558  */
 559 void __init batadv_netlink_register(void)
 560 {
 561         int ret;
 562
 563         ret = genl_register_family_with_ops_groups(&batadv_netlink_family,
 564                                                    batadv_netlink_ops,
 565                                                    batadv_netlink_mcgrps);
 566         if (ret)
 567                 pr_warn("unable to register netlink family");
 568 }
 569
 570 /**
 571  * batadv_netlink_unregister - unregister batadv genl netlink family
 572  */
 573 void batadv_netlink_unregister(void)
 574 {
 575         genl_unregister_family(&batadv_netlink_family);
 576 }