LXR linux/net/tipc/netlink.c

   1/*
   2 * net/tipc/netlink.c: TIPC configuration handling
   3 *
   4 * Copyright (c) 2005-2006, Ericsson AB
   5 * Copyright (c) 2005-2007, Wind River Systems
   6 * All rights reserved.
   7 *
   8 * Redistribution and use in source and binary forms, with or without
   9 * modification, are permitted provided that the following conditions are met:
  10 *
  11 * 1. Redistributions of source code must retain the above copyright
  12 *    notice, this list of conditions and the following disclaimer.
  13 * 2. Redistributions in binary form must reproduce the above copyright
  14 *    notice, this list of conditions and the following disclaimer in the
  15 *    documentation and/or other materials provided with the distribution.
  16 * 3. Neither the names of the copyright holders nor the names of its
  17 *    contributors may be used to endorse or promote products derived from
  18 *    this software without specific prior written permission.
  19 *
  20 * Alternatively, this software may be distributed under the terms of the
  21 * GNU General Public License ("GPL") version 2 as published by the Free
  22 * Software Foundation.
  23 *
  24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  34 * POSSIBILITY OF SUCH DAMAGE.
  35 */
  36
  37#include "core.h"
  38#include "config.h"
  39#include <net/genetlink.h>
  40
  41static int handle_cmd(struct sk_buff *skb, struct genl_info *info)
  42{
  43        struct sk_buff *rep_buf;
  44        struct nlmsghdr *rep_nlh;
  45        struct nlmsghdr *req_nlh = info->nlhdr;
  46        struct tipc_genlmsghdr *req_userhdr = info->userhdr;
  47        int hdr_space = NLMSG_SPACE(GENL_HDRLEN + TIPC_GENL_HDRLEN);
  48        u16 cmd;
  49
  50        if ((req_userhdr->cmd & 0xC000) && (!capable(CAP_NET_ADMIN)))
  51                cmd = TIPC_CMD_NOT_NET_ADMIN;
  52        else
  53                cmd = req_userhdr->cmd;
  54
  55        rep_buf = tipc_cfg_do_cmd(req_userhdr->dest, cmd,
  56                        NLMSG_DATA(req_nlh) + GENL_HDRLEN + TIPC_GENL_HDRLEN,
  57                        NLMSG_PAYLOAD(req_nlh, GENL_HDRLEN + TIPC_GENL_HDRLEN),
  58                        hdr_space);
  59
  60        if (rep_buf) {
  61                skb_push(rep_buf, hdr_space);
  62                rep_nlh = nlmsg_hdr(rep_buf);
  63                memcpy(rep_nlh, req_nlh, hdr_space);
  64                rep_nlh->nlmsg_len = rep_buf->len;
  65                genlmsg_unicast(&init_net, rep_buf, NETLINK_CB(skb).pid);
  66        }
  67
  68        return 0;
  69}
  70
  71static struct genl_family tipc_genl_family = {
  72        .id             = GENL_ID_GENERATE,
  73        .name           = TIPC_GENL_NAME,
  74        .version        = TIPC_GENL_VERSION,
  75        .hdrsize        = TIPC_GENL_HDRLEN,
  76        .maxattr        = 0,
  77};
  78
  79static struct genl_ops tipc_genl_ops = {
  80        .cmd            = TIPC_GENL_CMD,
  81        .doit           = handle_cmd,
  82};
  83
  84static int tipc_genl_family_registered;
  85
  86int tipc_netlink_start(void)
  87{
  88        int res;
  89
  90        res = genl_register_family_with_ops(&tipc_genl_family,
  91                &tipc_genl_ops, 1);
  92        if (res) {
  93                err("Failed to register netlink interface\n");
  94                return res;
  95        }
  96
  97        tipc_genl_family_registered = 1;
  98        return 0;
  99}
 100
 101void tipc_netlink_stop(void)
 102{
 103        if (!tipc_genl_family_registered)
 104                return;
 105
 106        genl_unregister_family(&tipc_genl_family);
 107        tipc_genl_family_registered = 0;
 108}
 109