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