ip/iplink_vrf.c

   1 /* iplink_vrf.c VRF device support
   2  *
   3  *              This program is free software; you can redistribute it and/or
   4  *              modify it under the terms of the GNU General Public License
   5  *              as published by the Free Software Foundation; either version
   6  *              2 of the License, or (at your option) any later version.
   7  *
   8  * Authors:     Shrijeet Mukherjee <shm@cumulusnetworks.com>
   9  */
  10
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <sys/socket.h>
  15 #include <linux/if_link.h>
  16 #include <errno.h>
  17
  18 #include "rt_names.h"
  19 #include "utils.h"
  20 #include "ip_common.h"
  21
  22 static void vrf_explain(FILE *f)
  23 {
  24         fprintf(f, "Usage: ... vrf table TABLEID\n");
  25 }
  26
  27 static void explain(void)
  28 {
  29         vrf_explain(stderr);
  30 }
  31
  32 static int vrf_parse_opt(struct link_util *lu, int argc, char **argv,
  33                             struct nlmsghdr *n)
  34 {
  35         while (argc > 0) {
  36                 if (matches(*argv, "table") == 0) {
  37                         __u32 table;
  38
  39                         NEXT_ARG();
  40
  41                         if (rtnl_rttable_a2n(&table, *argv))
  42                                 invarg("invalid table ID\n", *argv);
  43                         addattr32(n, 1024, IFLA_VRF_TABLE, table);
  44                 } else if (matches(*argv, "help") == 0) {
  45                         explain();
  46                         return -1;
  47                 } else {
  48                         fprintf(stderr, "vrf: unknown option \"%s\"?\n",
  49                                 *argv);
  50                         explain();
  51                         return -1;
  52                 }
  53                 argc--, argv++;
  54         }
  55
  56         return 0;
  57 }
  58
  59 static void vrf_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
  60 {
  61         if (!tb)
  62                 return;
  63
  64         if (tb[IFLA_VRF_TABLE])
  65                 print_uint(PRINT_ANY,
  66                            "table",
  67                            "table %u ",
  68                            rta_getattr_u32(tb[IFLA_VRF_TABLE]));
  69 }
  70
  71 static void vrf_slave_print_opt(struct link_util *lu, FILE *f,
  72                                 struct rtattr *tb[])
  73 {
  74         if (!tb)
  75                 return;
  76
  77         if (tb[IFLA_VRF_PORT_TABLE]) {
  78                 print_uint(PRINT_ANY,
  79                            "table",
  80                            "table %u ",
  81                            rta_getattr_u32(tb[IFLA_VRF_PORT_TABLE]));
  82         }
  83 }
  84
  85 static void vrf_print_help(struct link_util *lu, int argc, char **argv,
  86                            FILE *f)
  87 {
  88         vrf_explain(f);
  89 }
  90
  91 struct link_util vrf_link_util = {
  92         .id             = "vrf",
  93         .maxattr        = IFLA_VRF_MAX,
  94         .parse_opt      = vrf_parse_opt,
  95         .print_opt      = vrf_print_opt,
  96         .print_help     = vrf_print_help,
  97 };
  98
  99 struct link_util vrf_slave_link_util = {
 100         .id             = "vrf_slave",
 101         .maxattr        = IFLA_VRF_PORT_MAX,
 102         .print_opt      = vrf_slave_print_opt,
 103 };
 104
 105 /* returns table id if name is a VRF device */
 106 __u32 ipvrf_get_table(const char *name)
 107 {
 108         struct {
 109                 struct nlmsghdr         n;
 110                 struct ifinfomsg        i;
 111                 char                    buf[1024];
 112         } req = {
 113                 .n = {
 114                         .nlmsg_len   = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 115                         .nlmsg_flags = NLM_F_REQUEST,
 116                         .nlmsg_type  = RTM_GETLINK,
 117                 },
 118                 .i = {
 119                         .ifi_family  = preferred_family,
 120                 },
 121         };
 122         struct {
 123                 struct nlmsghdr n;
 124                 char buf[8192];
 125         } answer;
 126         struct rtattr *tb[IFLA_MAX+1];
 127         struct rtattr *li[IFLA_INFO_MAX+1];
 128         struct rtattr *vrf_attr[IFLA_VRF_MAX + 1];
 129         struct ifinfomsg *ifi;
 130         __u32 tb_id = 0;
 131         int len;
 132
 133         addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, strlen(name) + 1);
 134
 135         if (rtnl_talk_suppress_rtnl_errmsg(&rth, &req.n,
 136                                            &answer.n, sizeof(answer)) < 0) {
 137                 /* special case "default" vrf to be the main table */
 138                 if (errno == ENODEV && !strcmp(name, "default"))
 139                         if (rtnl_rttable_a2n(&tb_id, "main"))
 140                                 fprintf(stderr,
 141                                         "BUG: RTTable \"main\" not found.\n");
 142
 143                 return tb_id;
 144         }
 145
 146         ifi = NLMSG_DATA(&answer.n);
 147         len = answer.n.nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
 148         if (len < 0) {
 149                 fprintf(stderr, "BUG: Invalid response to link query.\n");
 150                 return 0;
 151         }
 152
 153         parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
 154
 155         if (!tb[IFLA_LINKINFO])
 156                 return 0;
 157
 158         parse_rtattr_nested(li, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
 159
 160         if (!li[IFLA_INFO_KIND] || !li[IFLA_INFO_DATA])
 161                 return 0;
 162
 163         if (strcmp(RTA_DATA(li[IFLA_INFO_KIND]), "vrf"))
 164                 return 0;
 165
 166         parse_rtattr_nested(vrf_attr, IFLA_VRF_MAX, li[IFLA_INFO_DATA]);
 167         if (vrf_attr[IFLA_VRF_TABLE])
 168                 tb_id = rta_getattr_u32(vrf_attr[IFLA_VRF_TABLE]);
 169
 170         if (!tb_id)
 171                 fprintf(stderr, "BUG: VRF %s is missing table id\n", name);
 172
 173         return tb_id;
 174 }
 175
 176 int name_is_vrf(const char *name)
 177 {
 178         struct {
 179                 struct nlmsghdr         n;
 180                 struct ifinfomsg        i;
 181                 char                    buf[1024];
 182         } req = {
 183                 .n = {
 184                         .nlmsg_len   = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 185                         .nlmsg_flags = NLM_F_REQUEST,
 186                         .nlmsg_type  = RTM_GETLINK,
 187                 },
 188                 .i = {
 189                         .ifi_family  = preferred_family,
 190                 },
 191         };
 192         struct {
 193                 struct nlmsghdr n;
 194                 char buf[8192];
 195         } answer;
 196         struct rtattr *tb[IFLA_MAX+1];
 197         struct rtattr *li[IFLA_INFO_MAX+1];
 198         struct ifinfomsg *ifi;
 199         int len;
 200
 201         addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, strlen(name) + 1);
 202
 203         if (rtnl_talk_suppress_rtnl_errmsg(&rth, &req.n,
 204                                            &answer.n, sizeof(answer)) < 0)
 205                 return 0;
 206
 207         ifi = NLMSG_DATA(&answer.n);
 208         len = answer.n.nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
 209         if (len < 0) {
 210                 fprintf(stderr, "BUG: Invalid response to link query.\n");
 211                 return 0;
 212         }
 213
 214         parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
 215
 216         if (!tb[IFLA_LINKINFO])
 217                 return 0;
 218
 219         parse_rtattr_nested(li, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
 220
 221         if (!li[IFLA_INFO_KIND])
 222                 return 0;
 223
 224         if (strcmp(RTA_DATA(li[IFLA_INFO_KIND]), "vrf"))
 225                 return 0;
 226
 227         return ifi->ifi_index;
 228 }