interface.c

   1 #include <net/if.h>
   2 #include <errno.h>
   3 #include <string.h>
   4 #include <stdbool.h>
   5
   6 #include <netlink/genl/genl.h>
   7 #include <netlink/genl/family.h>
   8 #include <netlink/genl/ctrl.h>
   9 #include <netlink/msg.h>
  10 #include <netlink/attr.h>
  11
  12 #include "nl80211.h"
  13 #include "iw.h"
  14
  15 #define VALID_FLAGS     "none:     no special flags\n"\
  16                         "fcsfail:  show frames with FCS errors\n"\
  17                         "control:  show control frames\n"\
  18                         "otherbss: show frames from other BSSes\n"\
  19                         "cook:     use cooked mode"
  20
  21 static char *mntr_flags[NL80211_MNTR_FLAG_MAX + 1] = {
  22         "none",
  23         "fcsfail",
  24         "plcpfail",
  25         "control",
  26         "otherbss",
  27         "cook",
  28 };
  29
  30 static int parse_mntr_flags(int *_argc, char ***_argv,
  31                             struct nl_msg *msg)
  32 {
  33         struct nl_msg *flags;
  34         int err = -ENOBUFS;
  35         enum nl80211_mntr_flags flag;
  36         int argc = *_argc;
  37         char **argv = *_argv;
  38
  39         flags = nlmsg_alloc();
  40         if (!flags)
  41                 return -ENOMEM;
  42
  43         while (argc) {
  44                 int ok = 0;
  45                 for (flag = __NL80211_MNTR_FLAG_INVALID;
  46                      flag <= NL80211_MNTR_FLAG_MAX; flag++) {
  47                         if (strcmp(*argv, mntr_flags[flag]) == 0) {
  48                                 ok = 1;
  49                                 /*
  50                                  * This shouldn't be adding "flag" if that is
  51                                  * zero, but due to a problem in the kernel's
  52                                  * nl80211 code (using NLA_NESTED policy) it
  53                                  * will reject an empty nested attribute but
  54                                  * not one that contains an invalid attribute
  55                                  */
  56                                 NLA_PUT_FLAG(flags, flag);
  57                                 break;
  58                         }
  59                 }
  60                 if (!ok) {
  61                         err = -EINVAL;
  62                         goto out;
  63                 }
  64                 argc--;
  65                 argv++;
  66         }
  67
  68         nla_put_nested(msg, NL80211_ATTR_MNTR_FLAGS, flags);
  69         err = 0;
  70  nla_put_failure:
  71  out:
  72         nlmsg_free(flags);
  73
  74         *_argc = argc;
  75         *_argv = argv;
  76
  77         return err;
  78 }
  79
  80 /* for help */
  81 #define IFACE_TYPES "Valid interface types are: managed, ibss, monitor, mesh, wds."
  82
  83 /* return 0 if ok, internal error otherwise */
  84 static int get_if_type(int *argc, char ***argv, enum nl80211_iftype *type,
  85                        bool need_type)
  86 {
  87         char *tpstr;
  88
  89         if (*argc < 1 + !!need_type)
  90                 return 1;
  91
  92         if (need_type && strcmp((*argv)[0], "type"))
  93                 return 1;
  94
  95         tpstr = (*argv)[!!need_type];
  96         *argc -= 1 + !!need_type;
  97         *argv += 1 + !!need_type;
  98
  99         if (strcmp(tpstr, "adhoc") == 0 ||
 100             strcmp(tpstr, "ibss") == 0) {
 101                 *type = NL80211_IFTYPE_ADHOC;
 102                 return 0;
 103         } else if (strcmp(tpstr, "monitor") == 0) {
 104                 *type = NL80211_IFTYPE_MONITOR;
 105                 return 0;
 106         } else if (strcmp(tpstr, "master") == 0) {
 107                 *type = NL80211_IFTYPE_UNSPECIFIED;
 108                 fprintf(stderr, "See http://wireless.kernel.org/RTFM-AP.\n");
 109                 return 2;
 110         } else if (strcmp(tpstr, "ap") == 0) {
 111                 *type = NL80211_IFTYPE_UNSPECIFIED;
 112                 fprintf(stderr, "See http://wireless.kernel.org/RTFM-AP.\n");
 113                 return 2;
 114         } else if (strcmp(tpstr, "__ap") == 0) {
 115                 *type = NL80211_IFTYPE_AP;
 116                 return 0;
 117         } else if (strcmp(tpstr, "__ap_vlan") == 0) {
 118                 *type = NL80211_IFTYPE_AP_VLAN;
 119                 return 0;
 120         } else if (strcmp(tpstr, "wds") == 0) {
 121                 *type = NL80211_IFTYPE_WDS;
 122                 return 0;
 123         } else if (strcmp(tpstr, "managed") == 0 ||
 124                    strcmp(tpstr, "mgd") == 0 ||
 125                    strcmp(tpstr, "station") == 0) {
 126                 *type = NL80211_IFTYPE_STATION;
 127                 return 0;
 128         } else if (strcmp(tpstr, "mp") == 0 ||
 129                    strcmp(tpstr, "mesh") == 0) {
 130                 *type = NL80211_IFTYPE_MESH_POINT;
 131                 return 0;
 132         }
 133
 134         fprintf(stderr, "invalid interface type %s\n", tpstr);
 135         return 2;
 136 }
 137
 138 static int handle_interface_add(struct nl80211_state *state,
 139                                 struct nl_cb *cb,
 140                                 struct nl_msg *msg,
 141                                 int argc, char **argv)
 142 {
 143         char *name;
 144         char *mesh_id = NULL;
 145         enum nl80211_iftype type;
 146         int tpset;
 147
 148         if (argc < 1)
 149                 return 1;
 150
 151         name = argv[0];
 152         argc--;
 153         argv++;
 154
 155         tpset = get_if_type(&argc, &argv, &type, true);
 156         if (tpset)
 157                 return tpset;
 158
 159         if (argc) {
 160                 if (strcmp(argv[0], "mesh_id") == 0) {
 161                         argc--;
 162                         argv++;
 163
 164                         if (!argc)
 165                                 return 1;
 166                         mesh_id = argv[0];
 167                         argc--;
 168                         argv++;
 169                 } else if (strcmp(argv[0], "flags") == 0) {
 170                         argc--;
 171                         argv++;
 172                         if (parse_mntr_flags(&argc, &argv, msg)) {
 173                                 fprintf(stderr, "flags error\n");
 174                                 return 2;
 175                         }
 176                 } else {
 177                         return 1;
 178                 }
 179         }
 180
 181         if (argc)
 182                 return 1;
 183
 184         NLA_PUT_STRING(msg, NL80211_ATTR_IFNAME, name);
 185         NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, type);
 186         if (mesh_id)
 187                 NLA_PUT(msg, NL80211_ATTR_MESH_ID, strlen(mesh_id), mesh_id);
 188
 189         return 0;
 190  nla_put_failure:
 191         return -ENOBUFS;
 192 }
 193 COMMAND(interface, add, "<name> type <type> [mesh_id <meshid>] [flags <flag>*]",
 194         NL80211_CMD_NEW_INTERFACE, 0, CIB_PHY, handle_interface_add,
 195         "Add a new virtual interface with the given configuration.\n"
 196         IFACE_TYPES "\n\n"
 197         "The flags are only used for monitor interfaces, valid flags are:\n"
 198         VALID_FLAGS "\n\n"
 199         "The mesh_id is used only for mesh mode.");
 200 COMMAND(interface, add, "<name> type <type> [mesh_id <meshid>] [flags <flag>*]",
 201         NL80211_CMD_NEW_INTERFACE, 0, CIB_NETDEV, handle_interface_add, NULL);
 202
 203 static int handle_interface_del(struct nl80211_state *state,
 204                                 struct nl_cb *cb,
 205                                 struct nl_msg *msg,
 206                                 int argc, char **argv)
 207 {
 208         return 0;
 209 }
 210 TOPLEVEL(del, NULL, NL80211_CMD_DEL_INTERFACE, 0, CIB_NETDEV, handle_interface_del,
 211          "Remove this virtual interface");
 212 HIDDEN(interface, del, NULL, NL80211_CMD_DEL_INTERFACE, 0, CIB_NETDEV, handle_interface_del);
 213
 214 static int print_iface_handler(struct nl_msg *msg, void *arg)
 215 {
 216         struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
 217         struct nlattr *tb_msg[NL80211_ATTR_MAX + 1];
 218         unsigned int *wiphy = arg;
 219         const char *indent = "";
 220
 221         nla_parse(tb_msg, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
 222                   genlmsg_attrlen(gnlh, 0), NULL);
 223
 224         if (wiphy && tb_msg[NL80211_ATTR_WIPHY]) {
 225                 unsigned int thiswiphy = nla_get_u32(tb_msg[NL80211_ATTR_WIPHY]);
 226                 indent = "\t";
 227                 if (*wiphy != thiswiphy)
 228                         printf("phy#%d\n", thiswiphy);
 229                 *wiphy = thiswiphy;
 230         }
 231
 232         if (tb_msg[NL80211_ATTR_IFNAME])
 233                 printf("%sInterface %s\n", indent, nla_get_string(tb_msg[NL80211_ATTR_IFNAME]));
 234         if (tb_msg[NL80211_ATTR_IFINDEX])
 235                 printf("%s\tifindex %d\n", indent, nla_get_u32(tb_msg[NL80211_ATTR_IFINDEX]));
 236         if (tb_msg[NL80211_ATTR_IFTYPE])
 237                 printf("%s\ttype %s\n", indent, iftype_name(nla_get_u32(tb_msg[NL80211_ATTR_IFTYPE])));
 238
 239         return NL_SKIP;
 240 }
 241
 242 static int handle_interface_info(struct nl80211_state *state,
 243                                  struct nl_cb *cb,
 244                                  struct nl_msg *msg,
 245                                  int argc, char **argv)
 246 {
 247         nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, print_iface_handler, NULL);
 248         return 0;
 249 }
 250 TOPLEVEL(info, NULL, NL80211_CMD_GET_INTERFACE, 0, CIB_NETDEV, handle_interface_info,
 251          "Show information for this interface.");
 252
 253 static int handle_interface_set(struct nl80211_state *state,
 254                                 struct nl_cb *cb,
 255                                 struct nl_msg *msg,
 256                                 int argc, char **argv)
 257 {
 258         if (!argc)
 259                 return 1;
 260
 261         NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, NL80211_IFTYPE_MONITOR);
 262
 263         switch (parse_mntr_flags(&argc, &argv, msg)) {
 264         case 0:
 265                 return 0;
 266         case -ENOMEM:
 267                 fprintf(stderr, "failed to allocate flags\n");
 268                 return 2;
 269         case -EINVAL:
 270                 fprintf(stderr, "unknown flag %s\n", *argv);
 271                 return 2;
 272         default:
 273                 return 2;
 274         }
 275  nla_put_failure:
 276         return -ENOBUFS;
 277 }
 278 COMMAND(set, monitor, "<flag>*",
 279         NL80211_CMD_SET_INTERFACE, 0, CIB_NETDEV, handle_interface_set,
 280         "Set monitor flags. Valid flags are:\n"
 281         VALID_FLAGS);
 282
 283 static int handle_interface_meshid(struct nl80211_state *state,
 284                                    struct nl_cb *cb,
 285                                    struct nl_msg *msg,
 286                                    int argc, char **argv)
 287 {
 288         char *mesh_id = NULL;
 289
 290         if (argc != 1)
 291                 return 1;
 292
 293         mesh_id = argv[0];
 294
 295         NLA_PUT(msg, NL80211_ATTR_MESH_ID, strlen(mesh_id), mesh_id);
 296
 297         return 0;
 298  nla_put_failure:
 299         return -ENOBUFS;
 300 }
 301 COMMAND(set, meshid, "<meshid>",
 302         NL80211_CMD_SET_INTERFACE, 0, CIB_NETDEV, handle_interface_meshid, NULL);
 303
 304 static unsigned int dev_dump_wiphy;
 305
 306 static int handle_dev_dump(struct nl80211_state *state,
 307                            struct nl_cb *cb,
 308                            struct nl_msg *msg,
 309                            int argc, char **argv)
 310 {
 311         dev_dump_wiphy = -1;
 312         nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, print_iface_handler, &dev_dump_wiphy);
 313         return 0;
 314 }
 315 TOPLEVEL(dev, NULL, NL80211_CMD_GET_INTERFACE, NLM_F_DUMP, CIB_NONE, handle_dev_dump,
 316          "List all network interfaces for wireless hardware.");
 317
 318 static int handle_interface_type(struct nl80211_state *state,
 319                                  struct nl_cb *cb,
 320                                  struct nl_msg *msg,
 321                                  int argc, char **argv)
 322 {
 323         enum nl80211_iftype type;
 324         int tpset;
 325
 326         tpset = get_if_type(&argc, &argv, &type, false);
 327         if (tpset)
 328                 return tpset;
 329
 330         if (argc)
 331                 return 1;
 332
 333         NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, type);
 334
 335         return 0;
 336  nla_put_failure:
 337         return -ENOBUFS;
 338 }
 339 COMMAND(set, type, "<type>",
 340         NL80211_CMD_SET_INTERFACE, 0, CIB_NETDEV, handle_interface_type,
 341         "Set interface type/mode.\n"
 342         IFACE_TYPES);