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