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 #define RTNL_HANDLE_F_STRICT_CHK                0x04
  27         int                     flags;
  28 };
  29
  30 struct nlmsg_list {
  31         struct nlmsg_list *next;
  32         struct nlmsghdr   h;
  33 };
  34
  35 struct nlmsg_chain {
  36         struct nlmsg_list *head;
  37         struct nlmsg_list *tail;
  38 };
  39
  40 extern int rcvbuf;
  41
  42 int rtnl_open(struct rtnl_handle *rth, unsigned int subscriptions)
  43         __attribute__((warn_unused_result));
  44
  45 int rtnl_open_byproto(struct rtnl_handle *rth, unsigned int subscriptions,
  46                              int protocol)
  47         __attribute__((warn_unused_result));
  48 int rtnl_add_nl_group(struct rtnl_handle *rth, unsigned int group)
  49         __attribute__((warn_unused_result));
  50 void rtnl_close(struct rtnl_handle *rth);
  51 void rtnl_set_strict_dump(struct rtnl_handle *rth);
  52
  53 typedef int (*req_filter_fn_t)(struct nlmsghdr *nlh, int reqlen);
  54
  55 int rtnl_addrdump_req(struct rtnl_handle *rth, int family,
  56                       req_filter_fn_t filter_fn)
  57         __attribute__((warn_unused_result));
  58 int rtnl_addrlbldump_req(struct rtnl_handle *rth, int family)
  59         __attribute__((warn_unused_result));
  60 int rtnl_routedump_req(struct rtnl_handle *rth, int family,
  61                        req_filter_fn_t filter_fn)
  62         __attribute__((warn_unused_result));
  63 int rtnl_ruledump_req(struct rtnl_handle *rth, int family)
  64         __attribute__((warn_unused_result));
  65 int rtnl_neighdump_req(struct rtnl_handle *rth, int family,
  66                        req_filter_fn_t filter_fn)
  67         __attribute__((warn_unused_result));
  68 int rtnl_neightbldump_req(struct rtnl_handle *rth, int family)
  69         __attribute__((warn_unused_result));
  70 int rtnl_mdbdump_req(struct rtnl_handle *rth, int family)
  71         __attribute__((warn_unused_result));
  72 int rtnl_netconfdump_req(struct rtnl_handle *rth, int family)
  73         __attribute__((warn_unused_result));
  74 int rtnl_nsiddump_req(struct rtnl_handle *rth, int family)
  75         __attribute__((warn_unused_result));
  76
  77 int rtnl_linkdump_req(struct rtnl_handle *rth, int fam)
  78         __attribute__((warn_unused_result));
  79 int rtnl_linkdump_req_filter(struct rtnl_handle *rth, int fam, __u32 filt_mask)
  80         __attribute__((warn_unused_result));
  81
  82 int rtnl_linkdump_req_filter_fn(struct rtnl_handle *rth, int fam,
  83                                 req_filter_fn_t fn)
  84         __attribute__((warn_unused_result));
  85 int rtnl_fdb_linkdump_req_filter_fn(struct rtnl_handle *rth,
  86                                     req_filter_fn_t filter_fn)
  87         __attribute__((warn_unused_result));
  88 int rtnl_statsdump_req_filter(struct rtnl_handle *rth, int fam, __u32 filt_mask)
  89         __attribute__((warn_unused_result));
  90 int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req,
  91                              int len)
  92         __attribute__((warn_unused_result));
  93 int rtnl_dump_request_n(struct rtnl_handle *rth, struct nlmsghdr *n)
  94         __attribute__((warn_unused_result));
  95
  96 int rtnl_nexthopdump_req(struct rtnl_handle *rth, int family,
  97                          req_filter_fn_t filter_fn)
  98         __attribute__((warn_unused_result));
  99
 100 struct rtnl_ctrl_data {
 101         int     nsid;
 102 };
 103
 104 typedef int (*rtnl_filter_t)(struct nlmsghdr *n, void *);
 105
 106 typedef int (*rtnl_listen_filter_t)(struct rtnl_ctrl_data *,
 107                                     struct nlmsghdr *n, void *);
 108
 109 typedef int (*nl_ext_ack_fn_t)(const char *errmsg, uint32_t off,
 110                                const struct nlmsghdr *inner_nlh);
 111
 112 struct rtnl_dump_filter_arg {
 113         rtnl_filter_t filter;
 114         void *arg1;
 115         __u16 nc_flags;
 116 };
 117
 118 int rtnl_dump_filter_nc(struct rtnl_handle *rth,
 119                         rtnl_filter_t filter,
 120                         void *arg, __u16 nc_flags);
 121 #define rtnl_dump_filter(rth, filter, arg) \
 122         rtnl_dump_filter_nc(rth, filter, arg, 0)
 123 int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 124               struct nlmsghdr **answer)
 125         __attribute__((warn_unused_result));
 126 int rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iovec, size_t iovlen,
 127                   struct nlmsghdr **answer)
 128         __attribute__((warn_unused_result));
 129 int rtnl_talk_suppress_rtnl_errmsg(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 130                                    struct nlmsghdr **answer)
 131         __attribute__((warn_unused_result));
 132 int rtnl_send(struct rtnl_handle *rth, const void *buf, int)
 133         __attribute__((warn_unused_result));
 134 int rtnl_send_check(struct rtnl_handle *rth, const void *buf, int)
 135         __attribute__((warn_unused_result));
 136 int nl_dump_ext_ack(const struct nlmsghdr *nlh, nl_ext_ack_fn_t errfn);
 137 int nl_dump_ext_ack_done(const struct nlmsghdr *nlh, int error);
 138
 139 int addattr(struct nlmsghdr *n, int maxlen, int type);
 140 int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data);
 141 int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data);
 142 int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data);
 143 int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data);
 144 int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *data);
 145
 146 int addattr_l(struct nlmsghdr *n, int maxlen, int type,
 147               const void *data, int alen);
 148 int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len);
 149 struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type);
 150 int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest);
 151 struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type,
 152                                    const void *data, int len);
 153 int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *nest);
 154 int rta_addattr8(struct rtattr *rta, int maxlen, int type, __u8 data);
 155 int rta_addattr16(struct rtattr *rta, int maxlen, int type, __u16 data);
 156 int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data);
 157 int rta_addattr64(struct rtattr *rta, int maxlen, int type, __u64 data);
 158 int rta_addattr_l(struct rtattr *rta, int maxlen, int type,
 159                   const void *data, int alen);
 160
 161 int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len);
 162 int parse_rtattr_flags(struct rtattr *tb[], int max, struct rtattr *rta,
 163                               int len, unsigned short flags);
 164 struct rtattr *parse_rtattr_one(int type, struct rtattr *rta, int len);
 165 int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta, int len);
 166
 167 struct rtattr *rta_nest(struct rtattr *rta, int maxlen, int type);
 168 int rta_nest_end(struct rtattr *rta, struct rtattr *nest);
 169
 170 #define RTA_TAIL(rta) \
 171                 ((struct rtattr *) (((void *) (rta)) + \
 172                                     RTA_ALIGN((rta)->rta_len)))
 173
 174 #define parse_rtattr_nested(tb, max, rta) \
 175         (parse_rtattr((tb), (max), RTA_DATA(rta), RTA_PAYLOAD(rta)))
 176
 177 #define parse_rtattr_one_nested(type, rta) \
 178         (parse_rtattr_one(type, RTA_DATA(rta), RTA_PAYLOAD(rta)))
 179
 180 #define parse_rtattr_nested_compat(tb, max, rta, data, len) \
 181         ({ data = RTA_PAYLOAD(rta) >= len ? RTA_DATA(rta) : NULL;       \
 182                 __parse_rtattr_nested_compat(tb, max, rta, len); })
 183
 184 static inline __u8 rta_getattr_u8(const struct rtattr *rta)
 185 {
 186         return *(__u8 *)RTA_DATA(rta);
 187 }
 188 static inline __u16 rta_getattr_u16(const struct rtattr *rta)
 189 {
 190         return *(__u16 *)RTA_DATA(rta);
 191 }
 192 static inline __be16 rta_getattr_be16(const struct rtattr *rta)
 193 {
 194         return ntohs(rta_getattr_u16(rta));
 195 }
 196 static inline __u32 rta_getattr_u32(const struct rtattr *rta)
 197 {
 198         return *(__u32 *)RTA_DATA(rta);
 199 }
 200 static inline __be32 rta_getattr_be32(const struct rtattr *rta)
 201 {
 202         return ntohl(rta_getattr_u32(rta));
 203 }
 204 static inline __u64 rta_getattr_u64(const struct rtattr *rta)
 205 {
 206         __u64 tmp;
 207
 208         memcpy(&tmp, RTA_DATA(rta), sizeof(__u64));
 209         return tmp;
 210 }
 211 static inline __s32 rta_getattr_s32(const struct rtattr *rta)
 212 {
 213         return *(__s32 *)RTA_DATA(rta);
 214 }
 215 static inline __s64 rta_getattr_s64(const struct rtattr *rta)
 216 {
 217         __s64 tmp;
 218
 219         memcpy(&tmp, RTA_DATA(rta), sizeof(tmp));
 220         return tmp;
 221 }
 222 static inline const char *rta_getattr_str(const struct rtattr *rta)
 223 {
 224         return (const char *)RTA_DATA(rta);
 225 }
 226
 227 int rtnl_listen_all_nsid(struct rtnl_handle *);
 228 int rtnl_listen(struct rtnl_handle *, rtnl_listen_filter_t handler,
 229                 void *jarg);
 230 int rtnl_from_file(FILE *, rtnl_listen_filter_t handler,
 231                    void *jarg);
 232
 233 #define NLMSG_TAIL(nmsg) \
 234         ((struct rtattr *) (((void *) (nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len)))
 235
 236 #ifndef IFA_RTA
 237 #define IFA_RTA(r) \
 238         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ifaddrmsg))))
 239 #endif
 240 #ifndef IFA_PAYLOAD
 241 #define IFA_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct ifaddrmsg))
 242 #endif
 243
 244 #ifndef IFLA_RTA
 245 #define IFLA_RTA(r) \
 246         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ifinfomsg))))
 247 #endif
 248 #ifndef IFLA_PAYLOAD
 249 #define IFLA_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct ifinfomsg))
 250 #endif
 251
 252 #ifndef NDA_RTA
 253 #define NDA_RTA(r) \
 254         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ndmsg))))
 255 #endif
 256 #ifndef NDA_PAYLOAD
 257 #define NDA_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct ndmsg))
 258 #endif
 259
 260 #ifndef NDTA_RTA
 261 #define NDTA_RTA(r) \
 262         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ndtmsg))))
 263 #endif
 264 #ifndef NDTA_PAYLOAD
 265 #define NDTA_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct ndtmsg))
 266 #endif
 267
 268 #ifndef NETNS_RTA
 269 #define NETNS_RTA(r) \
 270         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct rtgenmsg))))
 271 #endif
 272 #ifndef NETNS_PAYLOAD
 273 #define NETNS_PAYLOAD(n)        NLMSG_PAYLOAD(n, sizeof(struct rtgenmsg))
 274 #endif
 275
 276 #ifndef IFLA_STATS_RTA
 277 #define IFLA_STATS_RTA(r) \
 278         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct if_stats_msg))))
 279 #endif
 280
 281 /* User defined nlmsg_type which is used mostly for logging netlink
 282  * messages from dump file */
 283 #define NLMSG_TSTAMP    15
 284
 285 #endif /* __LIBNETLINK_H__ */