include/libnetlink.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __LIBNETLINK_H__
   3 #define __LIBNETLINK_H__ 1
   4
   5 #include <stdio.h>
   6 #include <string.h>
   7 #include <asm/types.h>
   8 #include <linux/netlink.h>
   9 #include <linux/rtnetlink.h>
  10 #include <linux/if_link.h>
  11 #include <linux/if_addr.h>
  12 #include <linux/neighbour.h>
  13 #include <linux/netconf.h>
  14 #include <arpa/inet.h>
  15
  16 struct rtnl_handle {
  17         int                     fd;
  18         struct sockaddr_nl      local;
  19         struct sockaddr_nl      peer;
  20         __u32                   seq;
  21         __u32                   dump;
  22         int                     proto;
  23         FILE                   *dump_fp;
  24 #define RTNL_HANDLE_F_LISTEN_ALL_NSID           0x01
  25 #define RTNL_HANDLE_F_SUPPRESS_NLERR            0x02
  26         int                     flags;
  27 };
  28
  29 struct nlmsg_list {
  30         struct nlmsg_list *next;
  31         struct nlmsghdr   h;
  32 };
  33
  34 struct nlmsg_chain {
  35         struct nlmsg_list *head;
  36         struct nlmsg_list *tail;
  37 };
  38
  39 extern int rcvbuf;
  40
  41 int rtnl_open(struct rtnl_handle *rth, unsigned int subscriptions)
  42         __attribute__((warn_unused_result));
  43
  44 int rtnl_open_byproto(struct rtnl_handle *rth, unsigned int subscriptions,
  45                              int protocol)
  46         __attribute__((warn_unused_result));
  47
  48 void rtnl_close(struct rtnl_handle *rth);
  49
  50 int rtnl_addrdump_req(struct rtnl_handle *rth, int family)
  51         __attribute__((warn_unused_result));
  52 int rtnl_addrlbldump_req(struct rtnl_handle *rth, int family)
  53         __attribute__((warn_unused_result));
  54 int rtnl_routedump_req(struct rtnl_handle *rth, int family)
  55         __attribute__((warn_unused_result));
  56 int rtnl_ruledump_req(struct rtnl_handle *rth, int family)
  57         __attribute__((warn_unused_result));
  58 int rtnl_neighdump_req(struct rtnl_handle *rth, int family)
  59         __attribute__((warn_unused_result));
  60 int rtnl_neightbldump_req(struct rtnl_handle *rth, int family)
  61         __attribute__((warn_unused_result));
  62 int rtnl_mdbdump_req(struct rtnl_handle *rth, int family)
  63         __attribute__((warn_unused_result));
  64 int rtnl_netconfdump_req(struct rtnl_handle *rth, int family)
  65         __attribute__((warn_unused_result));
  66 int rtnl_nsiddump_req(struct rtnl_handle *rth, int family)
  67         __attribute__((warn_unused_result));
  68
  69 int rtnl_linkdump_req(struct rtnl_handle *rth, int fam)
  70         __attribute__((warn_unused_result));
  71 int rtnl_linkdump_req_filter(struct rtnl_handle *rth, int fam, __u32 filt_mask)
  72         __attribute__((warn_unused_result));
  73
  74 typedef int (*req_filter_fn_t)(struct nlmsghdr *nlh, int reqlen);
  75
  76 int rtnl_linkdump_req_filter_fn(struct rtnl_handle *rth, int fam,
  77                                 req_filter_fn_t fn)
  78         __attribute__((warn_unused_result));
  79 int rtnl_statsdump_req_filter(struct rtnl_handle *rth, int fam, __u32 filt_mask)
  80         __attribute__((warn_unused_result));
  81 int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req,
  82                              int len)
  83         __attribute__((warn_unused_result));
  84 int rtnl_dump_request_n(struct rtnl_handle *rth, struct nlmsghdr *n)
  85         __attribute__((warn_unused_result));
  86
  87 struct rtnl_ctrl_data {
  88         int     nsid;
  89 };
  90
  91 typedef int (*rtnl_filter_t)(struct nlmsghdr *n, void *);
  92
  93 typedef int (*rtnl_listen_filter_t)(struct rtnl_ctrl_data *,
  94                                     struct nlmsghdr *n, void *);
  95
  96 typedef int (*nl_ext_ack_fn_t)(const char *errmsg, uint32_t off,
  97                                const struct nlmsghdr *inner_nlh);
  98
  99 struct rtnl_dump_filter_arg {
 100         rtnl_filter_t filter;
 101         void *arg1;
 102         __u16 nc_flags;
 103 };
 104
 105 int rtnl_dump_filter_nc(struct rtnl_handle *rth,
 106                         rtnl_filter_t filter,
 107                         void *arg, __u16 nc_flags);
 108 #define rtnl_dump_filter(rth, filter, arg) \
 109         rtnl_dump_filter_nc(rth, filter, arg, 0)
 110 int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 111               struct nlmsghdr **answer)
 112         __attribute__((warn_unused_result));
 113 int rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iovec, size_t iovlen,
 114                   struct nlmsghdr **answer)
 115         __attribute__((warn_unused_result));
 116 int rtnl_talk_suppress_rtnl_errmsg(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 117                                    struct nlmsghdr **answer)
 118         __attribute__((warn_unused_result));
 119 int rtnl_send(struct rtnl_handle *rth, const void *buf, int)
 120         __attribute__((warn_unused_result));
 121 int rtnl_send_check(struct rtnl_handle *rth, const void *buf, int)
 122         __attribute__((warn_unused_result));
 123 int nl_dump_ext_ack(const struct nlmsghdr *nlh, nl_ext_ack_fn_t errfn);
 124
 125 int addattr(struct nlmsghdr *n, int maxlen, int type);
 126 int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data);
 127 int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data);
 128 int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data);
 129 int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data);
 130 int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *data);
 131
 132 int addattr_l(struct nlmsghdr *n, int maxlen, int type,
 133               const void *data, int alen);
 134 int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len);
 135 struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type);
 136 int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest);
 137 struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type,
 138                                    const void *data, int len);
 139 int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *nest);
 140 int rta_addattr8(struct rtattr *rta, int maxlen, int type, __u8 data);
 141 int rta_addattr16(struct rtattr *rta, int maxlen, int type, __u16 data);
 142 int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data);
 143 int rta_addattr64(struct rtattr *rta, int maxlen, int type, __u64 data);
 144 int rta_addattr_l(struct rtattr *rta, int maxlen, int type,
 145                   const void *data, int alen);
 146
 147 int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len);
 148 int parse_rtattr_flags(struct rtattr *tb[], int max, struct rtattr *rta,
 149                               int len, unsigned short flags);
 150 struct rtattr *parse_rtattr_one(int type, struct rtattr *rta, int len);
 151 int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta, int len);
 152
 153 struct rtattr *rta_nest(struct rtattr *rta, int maxlen, int type);
 154 int rta_nest_end(struct rtattr *rta, struct rtattr *nest);
 155
 156 #define RTA_TAIL(rta) \
 157                 ((struct rtattr *) (((void *) (rta)) + \
 158                                     RTA_ALIGN((rta)->rta_len)))
 159
 160 #define parse_rtattr_nested(tb, max, rta) \
 161         (parse_rtattr((tb), (max), RTA_DATA(rta), RTA_PAYLOAD(rta)))
 162
 163 #define parse_rtattr_one_nested(type, rta) \
 164         (parse_rtattr_one(type, RTA_DATA(rta), RTA_PAYLOAD(rta)))
 165
 166 #define parse_rtattr_nested_compat(tb, max, rta, data, len) \
 167         ({ data = RTA_PAYLOAD(rta) >= len ? RTA_DATA(rta) : NULL;       \
 168                 __parse_rtattr_nested_compat(tb, max, rta, len); })
 169
 170 static inline __u8 rta_getattr_u8(const struct rtattr *rta)
 171 {
 172         return *(__u8 *)RTA_DATA(rta);
 173 }
 174 static inline __u16 rta_getattr_u16(const struct rtattr *rta)
 175 {
 176         return *(__u16 *)RTA_DATA(rta);
 177 }
 178 static inline __be16 rta_getattr_be16(const struct rtattr *rta)
 179 {
 180         return ntohs(rta_getattr_u16(rta));
 181 }
 182 static inline __u32 rta_getattr_u32(const struct rtattr *rta)
 183 {
 184         return *(__u32 *)RTA_DATA(rta);
 185 }
 186 static inline __be32 rta_getattr_be32(const struct rtattr *rta)
 187 {
 188         return ntohl(rta_getattr_u32(rta));
 189 }
 190 static inline __u64 rta_getattr_u64(const struct rtattr *rta)
 191 {
 192         __u64 tmp;
 193
 194         memcpy(&tmp, RTA_DATA(rta), sizeof(__u64));
 195         return tmp;
 196 }
 197 static inline __s32 rta_getattr_s32(const struct rtattr *rta)
 198 {
 199         return *(__s32 *)RTA_DATA(rta);
 200 }
 201 static inline __s64 rta_getattr_s64(const struct rtattr *rta)
 202 {
 203         __s64 tmp;
 204
 205         memcpy(&tmp, RTA_DATA(rta), sizeof(tmp));
 206         return tmp;
 207 }
 208 static inline const char *rta_getattr_str(const struct rtattr *rta)
 209 {
 210         return (const char *)RTA_DATA(rta);
 211 }
 212
 213 int rtnl_listen_all_nsid(struct rtnl_handle *);
 214 int rtnl_listen(struct rtnl_handle *, rtnl_listen_filter_t handler,
 215                 void *jarg);
 216 int rtnl_from_file(FILE *, rtnl_listen_filter_t handler,
 217                    void *jarg);
 218
 219 #define NLMSG_TAIL(nmsg) \
 220         ((struct rtattr *) (((void *) (nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len)))
 221
 222 #ifndef IFA_RTA
 223 #define IFA_RTA(r) \
 224         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ifaddrmsg))))
 225 #endif
 226 #ifndef IFA_PAYLOAD
 227 #define IFA_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct ifaddrmsg))
 228 #endif
 229
 230 #ifndef IFLA_RTA
 231 #define IFLA_RTA(r) \
 232         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ifinfomsg))))
 233 #endif
 234 #ifndef IFLA_PAYLOAD
 235 #define IFLA_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct ifinfomsg))
 236 #endif
 237
 238 #ifndef NDA_RTA
 239 #define NDA_RTA(r) \
 240         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ndmsg))))
 241 #endif
 242 #ifndef NDA_PAYLOAD
 243 #define NDA_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct ndmsg))
 244 #endif
 245
 246 #ifndef NDTA_RTA
 247 #define NDTA_RTA(r) \
 248         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ndtmsg))))
 249 #endif
 250 #ifndef NDTA_PAYLOAD
 251 #define NDTA_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct ndtmsg))
 252 #endif
 253
 254 #ifndef NETNS_RTA
 255 #define NETNS_RTA(r) \
 256         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct rtgenmsg))))
 257 #endif
 258 #ifndef NETNS_PAYLOAD
 259 #define NETNS_PAYLOAD(n)        NLMSG_PAYLOAD(n, sizeof(struct rtgenmsg))
 260 #endif
 261
 262 #ifndef IFLA_STATS_RTA
 263 #define IFLA_STATS_RTA(r) \
 264         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct if_stats_msg))))
 265 #endif
 266
 267 /* User defined nlmsg_type which is used mostly for logging netlink
 268  * messages from dump file */
 269 #define NLMSG_TSTAMP    15
 270
 271 #endif /* __LIBNETLINK_H__ */