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