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)(const struct sockaddr_nl *,
  92                              struct nlmsghdr *n, void *);
  93
  94 typedef int (*rtnl_listen_filter_t)(const struct sockaddr_nl *,
  95                                     struct rtnl_ctrl_data *,
  96                                     struct nlmsghdr *n, void *);
  97
  98 typedef int (*nl_ext_ack_fn_t)(const char *errmsg, uint32_t off,
  99                                const struct nlmsghdr *inner_nlh);
 100
 101 struct rtnl_dump_filter_arg {
 102         rtnl_filter_t filter;
 103         void *arg1;
 104         __u16 nc_flags;
 105 };
 106
 107 int rtnl_dump_filter_l(struct rtnl_handle *rth,
 108                               const struct rtnl_dump_filter_arg *arg);
 109 int rtnl_dump_filter_nc(struct rtnl_handle *rth,
 110                         rtnl_filter_t filter,
 111                         void *arg, __u16 nc_flags);
 112 #define rtnl_dump_filter(rth, filter, arg) \
 113         rtnl_dump_filter_nc(rth, filter, arg, 0)
 114 int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 115               struct nlmsghdr **answer)
 116         __attribute__((warn_unused_result));
 117 int rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iovec, size_t iovlen,
 118                   struct nlmsghdr **answer)
 119         __attribute__((warn_unused_result));
 120 int rtnl_talk_extack(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 121               struct nlmsghdr **answer, nl_ext_ack_fn_t errfn)
 122         __attribute__((warn_unused_result));
 123 int rtnl_talk_suppress_rtnl_errmsg(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 124                                    struct nlmsghdr **answer)
 125         __attribute__((warn_unused_result));
 126 int rtnl_send(struct rtnl_handle *rth, const void *buf, int)
 127         __attribute__((warn_unused_result));
 128 int rtnl_send_check(struct rtnl_handle *rth, const void *buf, int)
 129         __attribute__((warn_unused_result));
 130 int nl_dump_ext_ack(const struct nlmsghdr *nlh, nl_ext_ack_fn_t errfn);
 131
 132 int addattr(struct nlmsghdr *n, int maxlen, int type);
 133 int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data);
 134 int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data);
 135 int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data);
 136 int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data);
 137 int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *data);
 138
 139 int addattr_l(struct nlmsghdr *n, int maxlen, int type,
 140               const void *data, int alen);
 141 int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len);
 142 struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type);
 143 int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest);
 144 struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type,
 145                                    const void *data, int len);
 146 int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *nest);
 147 int rta_addattr8(struct rtattr *rta, int maxlen, int type, __u8 data);
 148 int rta_addattr16(struct rtattr *rta, int maxlen, int type, __u16 data);
 149 int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data);
 150 int rta_addattr64(struct rtattr *rta, int maxlen, int type, __u64 data);
 151 int rta_addattr_l(struct rtattr *rta, int maxlen, int type,
 152                   const void *data, int alen);
 153
 154 int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len);
 155 int parse_rtattr_flags(struct rtattr *tb[], int max, struct rtattr *rta,
 156                               int len, unsigned short flags);
 157 int parse_rtattr_byindex(struct rtattr *tb[], int max,
 158                          struct rtattr *rta, int len);
 159 struct rtattr *parse_rtattr_one(int type, struct rtattr *rta, int len);
 160 int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta, int len);
 161
 162 struct rtattr *rta_nest(struct rtattr *rta, int maxlen, int type);
 163 int rta_nest_end(struct rtattr *rta, struct rtattr *nest);
 164
 165 #define RTA_TAIL(rta) \
 166                 ((struct rtattr *) (((void *) (rta)) + \
 167                                     RTA_ALIGN((rta)->rta_len)))
 168
 169 #define parse_rtattr_nested(tb, max, rta) \
 170         (parse_rtattr((tb), (max), RTA_DATA(rta), RTA_PAYLOAD(rta)))
 171
 172 #define parse_rtattr_one_nested(type, rta) \
 173         (parse_rtattr_one(type, RTA_DATA(rta), RTA_PAYLOAD(rta)))
 174
 175 #define parse_rtattr_nested_compat(tb, max, rta, data, len) \
 176         ({ data = RTA_PAYLOAD(rta) >= len ? RTA_DATA(rta) : NULL;       \
 177                 __parse_rtattr_nested_compat(tb, max, rta, len); })
 178
 179 static inline __u8 rta_getattr_u8(const struct rtattr *rta)
 180 {
 181         return *(__u8 *)RTA_DATA(rta);
 182 }
 183 static inline __u16 rta_getattr_u16(const struct rtattr *rta)
 184 {
 185         return *(__u16 *)RTA_DATA(rta);
 186 }
 187 static inline __be16 rta_getattr_be16(const struct rtattr *rta)
 188 {
 189         return ntohs(rta_getattr_u16(rta));
 190 }
 191 static inline __u32 rta_getattr_u32(const struct rtattr *rta)
 192 {
 193         return *(__u32 *)RTA_DATA(rta);
 194 }
 195 static inline __be32 rta_getattr_be32(const struct rtattr *rta)
 196 {
 197         return ntohl(rta_getattr_u32(rta));
 198 }
 199 static inline __u64 rta_getattr_u64(const struct rtattr *rta)
 200 {
 201         __u64 tmp;
 202
 203         memcpy(&tmp, RTA_DATA(rta), sizeof(__u64));
 204         return tmp;
 205 }
 206 static inline __s32 rta_getattr_s32(const struct rtattr *rta)
 207 {
 208         return *(__s32 *)RTA_DATA(rta);
 209 }
 210 static inline __s64 rta_getattr_s64(const struct rtattr *rta)
 211 {
 212         __s64 tmp;
 213
 214         memcpy(&tmp, RTA_DATA(rta), sizeof(tmp));
 215         return tmp;
 216 }
 217 static inline const char *rta_getattr_str(const struct rtattr *rta)
 218 {
 219         return (const char *)RTA_DATA(rta);
 220 }
 221
 222 int rtnl_listen_all_nsid(struct rtnl_handle *);
 223 int rtnl_listen(struct rtnl_handle *, rtnl_listen_filter_t handler,
 224                 void *jarg);
 225 int rtnl_from_file(FILE *, rtnl_listen_filter_t handler,
 226                    void *jarg);
 227
 228 #define NLMSG_TAIL(nmsg) \
 229         ((struct rtattr *) (((void *) (nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len)))
 230
 231 #ifndef IFA_RTA
 232 #define IFA_RTA(r) \
 233         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ifaddrmsg))))
 234 #endif
 235 #ifndef IFA_PAYLOAD
 236 #define IFA_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct ifaddrmsg))
 237 #endif
 238
 239 #ifndef IFLA_RTA
 240 #define IFLA_RTA(r) \
 241         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ifinfomsg))))
 242 #endif
 243 #ifndef IFLA_PAYLOAD
 244 #define IFLA_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct ifinfomsg))
 245 #endif
 246
 247 #ifndef NDA_RTA
 248 #define NDA_RTA(r) \
 249         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ndmsg))))
 250 #endif
 251 #ifndef NDA_PAYLOAD
 252 #define NDA_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct ndmsg))
 253 #endif
 254
 255 #ifndef NDTA_RTA
 256 #define NDTA_RTA(r) \
 257         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct ndtmsg))))
 258 #endif
 259 #ifndef NDTA_PAYLOAD
 260 #define NDTA_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct ndtmsg))
 261 #endif
 262
 263 #ifndef NETNS_RTA
 264 #define NETNS_RTA(r) \
 265         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct rtgenmsg))))
 266 #endif
 267 #ifndef NETNS_PAYLOAD
 268 #define NETNS_PAYLOAD(n)        NLMSG_PAYLOAD(n, sizeof(struct rtgenmsg))
 269 #endif
 270
 271 #ifndef IFLA_STATS_RTA
 272 #define IFLA_STATS_RTA(r) \
 273         ((struct rtattr *)(((char *)(r)) + NLMSG_ALIGN(sizeof(struct if_stats_msg))))
 274 #endif
 275
 276 /* User defined nlmsg_type which is used mostly for logging netlink
 277  * messages from dump file */
 278 #define NLMSG_TSTAMP    15
 279
 280 #endif /* __LIBNETLINK_H__ */