net/netlabel/netlabel_user.c

   1 /*
   2  * NetLabel NETLINK Interface
   3  *
   4  * This file defines the NETLINK interface 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.moore@hp.com>
   9  *
  10  */
  11
  12 /*
  13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
  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/init.h>
  32 #include <linux/types.h>
  33 #include <linux/list.h>
  34 #include <linux/socket.h>
  35 #include <net/sock.h>
  36 #include <net/netlink.h>
  37 #include <net/genetlink.h>
  38 #include <net/netlabel.h>
  39 #include <asm/bug.h>
  40
  41 #include "netlabel_mgmt.h"
  42 #include "netlabel_unlabeled.h"
  43 #include "netlabel_cipso_v4.h"
  44 #include "netlabel_user.h"
  45
  46 /*
  47  * NetLabel NETLINK Setup Functions
  48  */
  49
  50 /**
  51  * netlbl_netlink_init - Initialize the NETLINK communication channel
  52  *
  53  * Description:
  54  * Call out to the NetLabel components so they can register their families and
  55  * commands with the Generic NETLINK mechanism.  Returns zero on success and
  56  * non-zero on failure.
  57  *
  58  */
  59 int netlbl_netlink_init(void)
  60 {
  61         int ret_val;
  62
  63         ret_val = netlbl_mgmt_genl_init();
  64         if (ret_val != 0)
  65                 return ret_val;
  66
  67         ret_val = netlbl_cipsov4_genl_init();
  68         if (ret_val != 0)
  69                 return ret_val;
  70
  71         ret_val = netlbl_unlabel_genl_init();
  72         if (ret_val != 0)
  73                 return ret_val;
  74
  75         return 0;
  76 }
  77
  78 /*
  79  * NetLabel Common Protocol Functions
  80  */
  81
  82 /**
  83  * netlbl_netlink_send_ack - Send an ACK message
  84  * @info: the generic NETLINK information
  85  * @genl_family: the generic NETLINK family ID value
  86  * @ack_cmd: the generic NETLINK family ACK command value
  87  * @ret_code: return code to use
  88  *
  89  * Description:
  90  * This function sends an ACK message to the sender of the NETLINK message
  91  * specified by @info.
  92  *
  93  */
  94 void netlbl_netlink_send_ack(const struct genl_info *info,
  95                              u32 genl_family,
  96                              u8 ack_cmd,
  97                              u32 ret_code)
  98 {
  99         size_t data_size;
 100         struct sk_buff *skb;
 101
 102         data_size = GENL_HDRLEN + 2 * NETLBL_LEN_U32;
 103         skb = netlbl_netlink_alloc_skb(0, data_size, GFP_KERNEL);
 104         if (skb == NULL)
 105                 return;
 106
 107         if (netlbl_netlink_hdr_put(skb,
 108                                    info->snd_pid,
 109                                    0,
 110                                    genl_family,
 111                                    ack_cmd) == NULL)
 112                 goto send_ack_failure;
 113
 114         if (nla_put_u32(skb, NLA_U32, info->snd_seq) != 0)
 115                 goto send_ack_failure;
 116         if (nla_put_u32(skb, NLA_U32, ret_code) != 0)
 117                 goto send_ack_failure;
 118
 119         netlbl_netlink_snd(skb, info->snd_pid);
 120         return;
 121
 122 send_ack_failure:
 123         kfree_skb(skb);
 124 }
 125
 126 /*
 127  * NETLINK I/O Functions
 128  */
 129
 130 /**
 131  * netlbl_netlink_snd - Send a NetLabel message
 132  * @skb: NetLabel message
 133  * @pid: destination PID
 134  *
 135  * Description:
 136  * Sends a unicast NetLabel message over the NETLINK socket.
 137  *
 138  */
 139 int netlbl_netlink_snd(struct sk_buff *skb, u32 pid)
 140 {
 141         return genlmsg_unicast(skb, pid);
 142 }
 143
 144 /**
 145  * netlbl_netlink_snd - Send a NetLabel message
 146  * @skb: NetLabel message
 147  * @pid: sending PID
 148  * @group: multicast group id
 149  *
 150  * Description:
 151  * Sends a multicast NetLabel message over the NETLINK socket to all members
 152  * of @group except @pid.
 153  *
 154  */
 155 int netlbl_netlink_snd_multicast(struct sk_buff *skb, u32 pid, u32 group)
 156 {
 157         return genlmsg_multicast(skb, pid, group, GFP_KERNEL);
 158 }