1 #ifndef __NET_NETLINK_WRAPPER_H
2 #define __NET_NETLINK_WRAPPER_H 1
4 #include <linux/version.h>
5 #include_next <net/netlink.h>
7 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
8 /* Before v2.6.29, a NLA_NESTED attribute, if it was present, was not allowed
9 * to be empty. However, OVS depends on the ability to accept empty
10 * attributes. For example, a present but empty ODP_FLOW_ATTR_ACTIONS on
11 * ODP_FLOW_CMD_SET replaces the existing set of actions by an empty "drop"
12 * action, whereas a missing ODP_FLOW_ATTR_ACTIONS leaves the existing
13 * actions, if any, unchanged.
15 * NLA_NESTED is different from NLA_UNSPEC in only two ways:
17 * - If the size of the nested attributes is zero, no further size checks
20 * - If the size of the nested attributes is not zero and no length
21 * parameter is specified the minimum size of nested attributes is
24 * nla_parse_nested() validates that there is at least enough space for
25 * NLA_HDRLEN, so neither of these conditions are important, and we might
26 * as well use NLA_UNSPEC with old kernels.
29 #define NLA_NESTED NLA_UNSPEC
32 #ifndef HAVE_NLA_NUL_STRING
33 static inline int VERIFY_NUL_STRING(struct nlattr *attr, int maxlen)
45 if (s[len - 1] != '\0')
51 static inline int VERIFY_NUL_STRING(struct nlattr *attr, int maxlen)
55 #endif /* !HAVE_NLA_NUL_STRING */
58 #define NLA_PUT_BE16(skb, attrtype, value) \
59 NLA_PUT_TYPE(skb, __be16, attrtype, value)
60 #endif /* !NLA_PUT_BE16 */
63 #define NLA_PUT_BE32(skb, attrtype, value) \
64 NLA_PUT_TYPE(skb, __be32, attrtype, value)
65 #endif /* !NLA_PUT_BE32 */
68 #define NLA_PUT_BE64(skb, attrtype, value) \
69 NLA_PUT_TYPE(skb, __be64, attrtype, value)
70 #endif /* !NLA_PUT_BE64 */
72 #ifndef HAVE_NLA_GET_BE16
74 * nla_get_be16 - return payload of __be16 attribute
75 * @nla: __be16 netlink attribute
77 static inline __be16 nla_get_be16(const struct nlattr *nla)
79 return *(__be16 *) nla_data(nla);
81 #endif /* !HAVE_NLA_GET_BE16 */
83 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
85 * nla_get_be32 - return payload of __be32 attribute
86 * @nla: __be32 netlink attribute
88 static inline __be32 nla_get_be32(const struct nlattr *nla)
90 return *(__be32 *) nla_data(nla);
94 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
95 /* These functions' nlattr source arguments weren't "const" before 2.6.29, so
96 * cast their arguments to the non-"const" versions. Using macros for this
97 * isn't exactly a brilliant idea, but it seems less error-prone than copying
98 * the definitions of all umpteen functions. */
99 #define nla_get_u64(nla) (nla_get_u64) ((struct nlattr *) (nla))
100 #define nla_get_u32(nla) (nla_get_u32) ((struct nlattr *) (nla))
101 #define nla_get_u16(nla) (nla_get_u16) ((struct nlattr *) (nla))
102 #define nla_get_u8(nla) (nla_get_u8) ((struct nlattr *) (nla))
103 /* nla_get_be64 is handled separately below. */
104 #define nla_get_be32(nla) (nla_get_be32) ((struct nlattr *) (nla))
105 #define nla_get_be16(nla) (nla_get_be16) ((struct nlattr *) (nla))
106 #define nla_get_be8(nla) (nla_get_be8) ((struct nlattr *) (nla))
107 #define nla_get_flag(nla) (nla_get_flag) ((struct nlattr *) (nla))
108 #define nla_get_msecs(nla) (nla_get_msecs)((struct nlattr *) (nla))
109 #define nla_memcpy(dst, src, count) \
110 (nla_memcpy)(dst, (struct nlattr *)(src), count)
113 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,34)
114 /* This function was introduced in 2.6.31, but initially it performed an
115 * unaligned access, so we replace it up to 2.6.34 where it was fixed. */
116 #define nla_get_be64 rpl_nla_get_be64
117 static inline __be64 nla_get_be64(const struct nlattr *nla)
121 /* The additional cast is necessary because */
122 nla_memcpy(&tmp, (struct nlattr *) nla, sizeof(tmp));
128 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24)
130 * nla_type - attribute type
131 * @nla: netlink attribute
133 static inline int nla_type(const struct nlattr *nla)
135 return nla->nla_type & NLA_TYPE_MASK;
139 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
140 #define nla_parse_nested(tb, maxtype, nla, policy) \
141 nla_parse_nested(tb, maxtype, (struct nlattr *)(nla), (struct nla_policy *)(policy))
142 #elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,29)
143 #define nla_parse_nested(tb, maxtype, nla, policy) \
144 nla_parse_nested(tb, maxtype, (struct nlattr *)(nla), policy)
147 #ifndef nla_for_each_nested
148 #define nla_for_each_nested(pos, nla, rem) \
149 nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
152 #ifndef HAVE_NLA_FIND_NESTED
153 static inline struct nlattr *nla_find_nested(struct nlattr *nla, int attrtype)
155 return nla_find(nla_data(nla), nla_len(nla), attrtype);
159 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
161 * nlmsg_report - need to report back to application?
162 * @nlh: netlink message header
164 * Returns 1 if a report back to the application is requested.
166 static inline int nlmsg_report(const struct nlmsghdr *nlh)
168 return !!(nlh->nlmsg_flags & NLM_F_ECHO);
171 extern int nlmsg_notify(struct sock *sk, struct sk_buff *skb,
172 u32 pid, unsigned int group, int report,
174 #endif /* linux kernel < 2.6.19 */
176 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
177 /* Before 2.6.19 the 'flags' parameter was missing, so replace it. We have to
178 * #include <net/genetlink.h> first because the 2.6.18 version of that header
179 * has an inline call to nlmsg_multicast() without, of course, any 'flags'
181 #define nlmsg_multicast rpl_nlmsg_multicast
182 static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
183 u32 pid, unsigned int group, gfp_t flags)
187 NETLINK_CB(skb).dst_group = group;
189 err = netlink_broadcast(sk, skb, pid, group, flags);
195 #endif /* linux kernel < 2.6.19 */
197 #endif /* net/netlink.h */