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9#ifndef __LIBBPF_NLATTR_H
10#define __LIBBPF_NLATTR_H
11
12#include <stdint.h>
13#include <string.h>
14#include <errno.h>
15#include <linux/netlink.h>
16#include <linux/rtnetlink.h>
17
18
19#define __LINUX_NETLINK_H
20
21
22
23
24enum {
25 LIBBPF_NLA_UNSPEC,
26 LIBBPF_NLA_U8,
27 LIBBPF_NLA_U16,
28 LIBBPF_NLA_U32,
29 LIBBPF_NLA_U64,
30 LIBBPF_NLA_STRING,
31 LIBBPF_NLA_FLAG,
32 LIBBPF_NLA_MSECS,
33 LIBBPF_NLA_NESTED,
34 __LIBBPF_NLA_TYPE_MAX,
35};
36
37#define LIBBPF_NLA_TYPE_MAX (__LIBBPF_NLA_TYPE_MAX - 1)
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39
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43
44
45struct libbpf_nla_policy {
46
47 uint16_t type;
48
49
50 uint16_t minlen;
51
52
53 uint16_t maxlen;
54};
55
56struct libbpf_nla_req {
57 struct nlmsghdr nh;
58 union {
59 struct ifinfomsg ifinfo;
60 struct tcmsg tc;
61 };
62 char buf[128];
63};
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70
71
72
73#define libbpf_nla_for_each_attr(pos, head, len, rem) \
74 for (pos = head, rem = len; \
75 nla_ok(pos, rem); \
76 pos = nla_next(pos, &(rem)))
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78
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80
81
82static inline void *libbpf_nla_data(const struct nlattr *nla)
83{
84 return (void *)nla + NLA_HDRLEN;
85}
86
87static inline uint8_t libbpf_nla_getattr_u8(const struct nlattr *nla)
88{
89 return *(uint8_t *)libbpf_nla_data(nla);
90}
91
92static inline uint32_t libbpf_nla_getattr_u32(const struct nlattr *nla)
93{
94 return *(uint32_t *)libbpf_nla_data(nla);
95}
96
97static inline const char *libbpf_nla_getattr_str(const struct nlattr *nla)
98{
99 return (const char *)libbpf_nla_data(nla);
100}
101
102
103
104
105
106static inline int libbpf_nla_len(const struct nlattr *nla)
107{
108 return nla->nla_len - NLA_HDRLEN;
109}
110
111int libbpf_nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head,
112 int len, struct libbpf_nla_policy *policy);
113int libbpf_nla_parse_nested(struct nlattr *tb[], int maxtype,
114 struct nlattr *nla,
115 struct libbpf_nla_policy *policy);
116
117int libbpf_nla_dump_errormsg(struct nlmsghdr *nlh);
118
119static inline struct nlattr *nla_data(struct nlattr *nla)
120{
121 return (struct nlattr *)((void *)nla + NLA_HDRLEN);
122}
123
124static inline struct nlattr *req_tail(struct libbpf_nla_req *req)
125{
126 return (struct nlattr *)((void *)req + NLMSG_ALIGN(req->nh.nlmsg_len));
127}
128
129static inline int nlattr_add(struct libbpf_nla_req *req, int type,
130 const void *data, int len)
131{
132 struct nlattr *nla;
133
134 if (NLMSG_ALIGN(req->nh.nlmsg_len) + NLA_ALIGN(NLA_HDRLEN + len) > sizeof(*req))
135 return -EMSGSIZE;
136 if (!!data != !!len)
137 return -EINVAL;
138
139 nla = req_tail(req);
140 nla->nla_type = type;
141 nla->nla_len = NLA_HDRLEN + len;
142 if (data)
143 memcpy(nla_data(nla), data, len);
144 req->nh.nlmsg_len = NLMSG_ALIGN(req->nh.nlmsg_len) + NLA_ALIGN(nla->nla_len);
145 return 0;
146}
147
148static inline struct nlattr *nlattr_begin_nested(struct libbpf_nla_req *req, int type)
149{
150 struct nlattr *tail;
151
152 tail = req_tail(req);
153 if (nlattr_add(req, type | NLA_F_NESTED, NULL, 0))
154 return NULL;
155 return tail;
156}
157
158static inline void nlattr_end_nested(struct libbpf_nla_req *req,
159 struct nlattr *tail)
160{
161 tail->nla_len = (void *)req_tail(req) - (void *)tail;
162}
163
164#endif
165