xref: /linux/net/netlabel/netlabel_user.c (revision 2dc94310bd94d0906febea7d0f7c188da620c952)
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 }
159