2 * Copyright (c) 2008, 2010, 2011 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #ifndef NETLINK_PROTOCOL_H
18 #define NETLINK_PROTOCOL_H 1
20 /* Netlink protocol definitions.
22 * Netlink is a message framing format described in RFC 3549 and used heavily
23 * in Linux to access the network stack. Open vSwitch uses AF_NETLINK sockets
24 * for this purpose on Linux. But on all platforms, Open vSwitch uses Netlink
25 * message framing internally for certain purposes.
27 * This header provides access to the Netlink message framing definitions
28 * regardless of platform. On Linux, it includes the proper headers directly;
29 * on other platforms it directly defines the structures and macros itself.
33 #include <sys/socket.h>
37 #include <linux/netlink.h>
38 #include <linux/genetlink.h>
40 #define NETLINK_GENERIC 16
43 sa_family_t nl_family;
44 unsigned short int nl_pad;
48 BUILD_ASSERT_DECL(sizeof(struct sockaddr_nl) == 12);
50 /* nlmsg_flags bits. */
51 #define NLM_F_REQUEST 0x001
52 #define NLM_F_MULTI 0x002
53 #define NLM_F_ACK 0x004
54 #define NLM_F_ECHO 0x008
56 #define NLM_F_ROOT 0x100
57 #define NLM_F_MATCH 0x200
58 #define NLM_F_ATOMIC 0x400
59 #define NLM_F_DUMP (NLM_F_ROOT | NLM_F_MATCH)
61 /* nlmsg_type values. */
65 #define NLMSG_OVERRUN 4
67 #define NLMSG_MIN_TYPE 0x10
76 BUILD_ASSERT_DECL(sizeof(struct nlmsghdr) == 16);
78 #define NLMSG_ALIGNTO 4
79 #define NLMSG_ALIGN(SIZE) ROUND_UP(SIZE, NLMSG_ALIGNTO)
80 #define NLMSG_HDRLEN ((int) NLMSG_ALIGN(sizeof(struct nlmsghdr)))
87 BUILD_ASSERT_DECL(sizeof(struct nlmsgerr) == 20);
94 BUILD_ASSERT_DECL(sizeof(struct genlmsghdr) == 4);
96 #define GENL_HDRLEN NLMSG_ALIGN(sizeof(struct genlmsghdr))
102 BUILD_ASSERT_DECL(sizeof(struct nlattr) == 4);
104 #define NLA_ALIGNTO 4
105 #define NLA_ALIGN(SIZE) ROUND_UP(SIZE, NLA_ALIGNTO)
106 #define NLA_HDRLEN ((int) NLA_ALIGN(sizeof(struct nlattr)))
108 #define GENL_MIN_ID NLMSG_MIN_TYPE
109 #define GENL_MAX_ID 1023
111 #define GENL_ID_CTRL NLMSG_MIN_TYPE
124 #define CTRL_CMD_MAX (__CTRL_CMD_MAX - 1)
129 CTRL_ATTR_FAMILY_NAME,
137 #define CTRL_ATTR_MAX (__CTRL_ATTR_MAX - 1)
146 #define CTRL_ATTR_OP_MAX (__CTRL_ATTR_OP_MAX - 1)
147 #endif /* !HAVE_NETLINK */
149 /* These were introduced all together in 2.6.24. */
150 #ifndef NLA_TYPE_MASK
151 #define NLA_F_NESTED (1 << 15)
152 #define NLA_F_NET_BYTEORDER (1 << 14)
153 #define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER)
156 /* These were introduced all together in 2.6.14. (We want our programs to
157 * support the newer kernel features even if compiled with older headers.) */
158 #ifndef NETLINK_ADD_MEMBERSHIP
159 #define NETLINK_ADD_MEMBERSHIP 1
160 #define NETLINK_DROP_MEMBERSHIP 2
163 #endif /* netlink-protocol.h */