src/network/networkd-wifi.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <net/ethernet.h>
   4 #include <linux/nl80211.h>
   5
   6 #include "ether-addr-util.h"
   7 #include "netlink-util.h"
   8 #include "networkd-link.h"
   9 #include "networkd-manager.h"
  10 #include "networkd-wifi.h"
  11 #include "networkd-wiphy.h"
  12 #include "string-util.h"
  13 #include "wifi-util.h"
  14
  15 int link_get_wlan_interface(Link *link) {
  16         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
  17         int r;
  18
  19         assert(link);
  20
  21         r = sd_genl_message_new(link->manager->genl, NL80211_GENL_NAME, NL80211_CMD_GET_INTERFACE, &req);
  22         if (r < 0)
  23                 return log_link_debug_errno(link, r, "Failed to create generic netlink message: %m");
  24
  25         r = sd_netlink_message_append_u32(req, NL80211_ATTR_IFINDEX, link->ifindex);
  26         if (r < 0)
  27                 return log_link_debug_errno(link, r, "Could not append NL80211_ATTR_IFINDEX attribute: %m");
  28
  29         r = sd_netlink_call(link->manager->genl, req, 0, &reply);
  30         if (r < 0)
  31                 return log_link_debug_errno(link, r, "Failed to request information about wlan interface: %m");
  32         if (!reply) {
  33                 log_link_debug(link, "No reply received to request for information about wifi interface, ignoring.");
  34                 return 0;
  35         }
  36
  37         return manager_genl_process_nl80211_config(link->manager->genl, reply, link->manager);
  38 }
  39
  40 int manager_genl_process_nl80211_config(sd_netlink *genl, sd_netlink_message *message, Manager *manager) {
  41         _cleanup_free_ char *ssid = NULL;
  42         uint32_t ifindex, wlan_iftype;
  43         const char *family, *ifname;
  44         uint8_t cmd;
  45         size_t len;
  46         Link *link;
  47         int r;
  48
  49         assert(genl);
  50         assert(message);
  51         assert(manager);
  52
  53         if (sd_netlink_message_is_error(message)) {
  54                 r = sd_netlink_message_get_errno(message);
  55                 if (r < 0)
  56                         log_message_warning_errno(message, r, "nl80211: received error message, ignoring");
  57
  58                 return 0;
  59         }
  60
  61         r = sd_genl_message_get_family_name(genl, message, &family);
  62         if (r < 0) {
  63                 log_debug_errno(r, "nl80211: failed to determine genl family, ignoring: %m");
  64                 return 0;
  65         }
  66         if (!streq(family, NL80211_GENL_NAME)) {
  67                 log_debug("nl80211: received message of unexpected genl family '%s', ignoring.", family);
  68                 return 0;
  69         }
  70
  71         r = sd_genl_message_get_command(genl, message, &cmd);
  72         if (r < 0) {
  73                 log_debug_errno(r, "nl80211: failed to determine genl message command, ignoring: %m");
  74                 return 0;
  75         }
  76         if (IN_SET(cmd, NL80211_CMD_NEW_WIPHY, NL80211_CMD_DEL_WIPHY))
  77                 return manager_genl_process_nl80211_wiphy(genl, message, manager);
  78         if (!IN_SET(cmd, NL80211_CMD_SET_INTERFACE, NL80211_CMD_NEW_INTERFACE, NL80211_CMD_DEL_INTERFACE)) {
  79                 log_debug("nl80211: ignoring nl80211 %s(%u) message.",
  80                           strna(nl80211_cmd_to_string(cmd)), cmd);
  81                 return 0;
  82         }
  83
  84         r = sd_netlink_message_read_u32(message, NL80211_ATTR_IFINDEX, &ifindex);
  85         if (r < 0) {
  86                 log_debug_errno(r, "nl80211: received %s(%u) message without valid ifindex, ignoring: %m",
  87                                 strna(nl80211_cmd_to_string(cmd)), cmd);
  88                 return 0;
  89         }
  90
  91         r = link_get_by_index(manager, ifindex, &link);
  92         if (r < 0) {
  93                 log_debug_errno(r, "nl80211: received %s(%u) message for link '%"PRIu32"' we don't know about, ignoring.",
  94                                 strna(nl80211_cmd_to_string(cmd)), cmd, ifindex);
  95
  96                 /* The NL80211_CMD_NEW_INTERFACE message might arrive before RTM_NEWLINK, in which case a
  97                  * link will not have been created yet. Store the interface index such that the wireless
  98                  * properties of the link (such as wireless interface type) are queried again after the link
  99                  * is created.
 100                  */
 101                 if (cmd == NL80211_CMD_NEW_INTERFACE) {
 102                         r = set_ensure_put(&manager->new_wlan_ifindices, NULL, INT_TO_PTR(ifindex));
 103                         if (r < 0)
 104                                 log_warning_errno(r, "Failed to add new wireless interface index to set, ignoring: %m");
 105                 } else if (cmd == NL80211_CMD_DEL_INTERFACE)
 106                         set_remove(manager->new_wlan_ifindices, INT_TO_PTR(ifindex));
 107
 108                 return 0;
 109         }
 110
 111         r = sd_netlink_message_read_string(message, NL80211_ATTR_IFNAME, &ifname);
 112         if (r < 0) {
 113                 log_link_debug_errno(link, r, "nl80211: received %s(%u) message without valid interface name, ignoring: %m",
 114                                      strna(nl80211_cmd_to_string(cmd)), cmd);
 115                 return 0;
 116         }
 117
 118         if (!streq(ifname, link->ifname)) {
 119                 log_link_debug(link, "nl80211: received %s(%u) message with invalid interface name '%s', ignoring: %m",
 120                                strna(nl80211_cmd_to_string(cmd)), cmd, ifname);
 121                 return 0;
 122         }
 123
 124         r = sd_netlink_message_read_u32(message, NL80211_ATTR_IFTYPE, &wlan_iftype);
 125         if (r < 0) {
 126                 log_link_debug_errno(link, r, "nl80211: received %s(%u) message without valid wlan interface type, ignoring: %m",
 127                                      strna(nl80211_cmd_to_string(cmd)), cmd);
 128                 return 0;
 129         }
 130
 131         r = sd_netlink_message_read_data(message, NL80211_ATTR_SSID, &len, (void**) &ssid);
 132         if (r < 0 && r != -ENODATA) {
 133                 log_link_debug_errno(link, r, "nl80211: received %s(%u) message without valid SSID, ignoring: %m",
 134                                      strna(nl80211_cmd_to_string(cmd)), cmd);
 135                 return 0;
 136         }
 137         if (r >= 0) {
 138                 if (len == 0) {
 139                         log_link_debug(link, "nl80211: received SSID has zero length, ignoring it: %m");
 140                         ssid = mfree(ssid);
 141                 } else if (strlen_ptr(ssid) != len) {
 142                         log_link_debug(link, "nl80211: received SSID contains NUL characters, ignoring it.");
 143                         ssid = mfree(ssid);
 144                 }
 145         }
 146
 147         log_link_debug(link, "nl80211: received %s(%u) message: iftype=%s, ssid=%s",
 148                        strna(nl80211_cmd_to_string(cmd)), cmd,
 149                        strna(nl80211_iftype_to_string(wlan_iftype)), strna(ssid));
 150
 151         switch (cmd) {
 152         case NL80211_CMD_SET_INTERFACE:
 153         case NL80211_CMD_NEW_INTERFACE:
 154                 link->wlan_iftype = wlan_iftype;
 155                 free_and_replace(link->ssid, ssid);
 156                 break;
 157
 158         case NL80211_CMD_DEL_INTERFACE:
 159                 link->wlan_iftype = NL80211_IFTYPE_UNSPECIFIED;
 160                 link->ssid = mfree(link->ssid);
 161                 break;
 162
 163         default:
 164                 assert_not_reached();
 165         }
 166
 167         return 0;
 168 }
 169
 170 int manager_genl_process_nl80211_mlme(sd_netlink *genl, sd_netlink_message *message, Manager *manager) {
 171         const char *family;
 172         uint32_t ifindex;
 173         uint8_t cmd;
 174         Link *link;
 175         int r;
 176
 177         assert(genl);
 178         assert(message);
 179         assert(manager);
 180
 181         if (sd_netlink_message_is_error(message)) {
 182                 r = sd_netlink_message_get_errno(message);
 183                 if (r < 0)
 184                         log_message_warning_errno(message, r, "nl80211: received error message, ignoring");
 185
 186                 return 0;
 187         }
 188
 189         r = sd_genl_message_get_family_name(genl, message, &family);
 190         if (r < 0) {
 191                 log_debug_errno(r, "nl80211: failed to determine genl family, ignoring: %m");
 192                 return 0;
 193         }
 194         if (!streq(family, NL80211_GENL_NAME)) {
 195                 log_debug("nl80211: Received message of unexpected genl family '%s', ignoring.", family);
 196                 return 0;
 197         }
 198
 199         r = sd_genl_message_get_command(genl, message, &cmd);
 200         if (r < 0) {
 201                 log_debug_errno(r, "nl80211: failed to determine genl message command, ignoring: %m");
 202                 return 0;
 203         }
 204
 205         r = sd_netlink_message_read_u32(message, NL80211_ATTR_IFINDEX, &ifindex);
 206         if (r < 0) {
 207                 log_debug_errno(r, "nl80211: received %s(%u) message without valid ifindex, ignoring: %m",
 208                                 strna(nl80211_cmd_to_string(cmd)), cmd);
 209                 return 0;
 210         }
 211
 212         r = link_get_by_index(manager, ifindex, &link);
 213         if (r < 0) {
 214                 log_debug_errno(r, "nl80211: received %s(%u) message for link '%"PRIu32"' we don't know about, ignoring.",
 215                                 strna(nl80211_cmd_to_string(cmd)), cmd, ifindex);
 216                 return 0;
 217         }
 218
 219         switch (cmd) {
 220         case NL80211_CMD_NEW_STATION:
 221         case NL80211_CMD_DEL_STATION: {
 222                 struct ether_addr bssid;
 223
 224                 r = sd_netlink_message_read_ether_addr(message, NL80211_ATTR_MAC, &bssid);
 225                 if (r < 0) {
 226                         log_link_debug_errno(link, r, "nl80211: received %s(%u) message without valid BSSID, ignoring: %m",
 227                                              strna(nl80211_cmd_to_string(cmd)), cmd);
 228                         return 0;
 229                 }
 230
 231                 log_link_debug(link, "nl80211: received %s(%u) message: bssid=%s",
 232                                strna(nl80211_cmd_to_string(cmd)), cmd, ETHER_ADDR_TO_STR(&bssid));
 233
 234                 if (cmd == NL80211_CMD_DEL_STATION) {
 235                         link->bssid = ETHER_ADDR_NULL;
 236                         return 0;
 237                 }
 238
 239                 link->bssid = bssid;
 240
 241                 if (manager->enumerating &&
 242                     link->wlan_iftype == NL80211_IFTYPE_STATION && link->ssid)
 243                         log_link_info(link, "Connected WiFi access point: %s (%s)",
 244                                       link->ssid, ETHER_ADDR_TO_STR(&link->bssid));
 245                 break;
 246         }
 247         case NL80211_CMD_CONNECT: {
 248                 struct ether_addr bssid;
 249                 uint16_t status_code;
 250
 251                 r = sd_netlink_message_read_ether_addr(message, NL80211_ATTR_MAC, &bssid);
 252                 if (r < 0 && r != -ENODATA) {
 253                         log_link_debug_errno(link, r, "nl80211: received %s(%u) message without valid BSSID, ignoring: %m",
 254                                              strna(nl80211_cmd_to_string(cmd)), cmd);
 255                         return 0;
 256                 }
 257
 258                 r = sd_netlink_message_read_u16(message, NL80211_ATTR_STATUS_CODE, &status_code);
 259                 if (r < 0) {
 260                         log_link_debug_errno(link, r, "nl80211: received %s(%u) message without valid status code, ignoring: %m",
 261                                              strna(nl80211_cmd_to_string(cmd)), cmd);
 262                         return 0;
 263                 }
 264
 265                 log_link_debug(link, "nl80211: received %s(%u) message: status=%u, bssid=%s",
 266                                strna(nl80211_cmd_to_string(cmd)), cmd, status_code, ETHER_ADDR_TO_STR(&bssid));
 267
 268                 if (status_code != 0)
 269                         return 0;
 270
 271                 link->bssid = bssid;
 272
 273                 if (!manager->enumerating) {
 274                         r = link_get_wlan_interface(link);
 275                         if (r < 0) {
 276                                 log_link_warning_errno(link, r, "Failed to update wireless LAN interface: %m");
 277                                 link_enter_failed(link);
 278                                 return 0;
 279                         }
 280                 }
 281
 282                 if (link->wlan_iftype == NL80211_IFTYPE_STATION && link->ssid)
 283                         log_link_info(link, "Connected WiFi access point: %s (%s)",
 284                                       link->ssid, ETHER_ADDR_TO_STR(&link->bssid));
 285
 286                 /* Sometimes, RTM_NEWLINK message with carrier is received earlier than NL80211_CMD_CONNECT.
 287                  * To make SSID= or other WiFi related settings in [Match] section work, let's try to
 288                  * reconfigure the interface. */
 289                 if (link->ssid && link_has_carrier(link)) {
 290                         r = link_reconfigure_impl(link, /* force = */ false);
 291                         if (r < 0) {
 292                                 log_link_warning_errno(link, r, "Failed to reconfigure interface: %m");
 293                                 link_enter_failed(link);
 294                                 return 0;
 295                         }
 296                 }
 297                 break;
 298         }
 299         case NL80211_CMD_DISCONNECT:
 300                 log_link_debug(link, "nl80211: received %s(%u) message.",
 301                                strna(nl80211_cmd_to_string(cmd)), cmd);
 302
 303                 link->bssid = ETHER_ADDR_NULL;
 304                 free_and_replace(link->previous_ssid, link->ssid);
 305                 break;
 306
 307         case NL80211_CMD_START_AP: {
 308                 log_link_debug(link, "nl80211: received %s(%u) message.",
 309                                strna(nl80211_cmd_to_string(cmd)), cmd);
 310
 311                 /* No need to reconfigure during enumeration */
 312                 if (manager->enumerating)
 313                         break;
 314
 315                 /* If there is no carrier, let the link get configured on
 316                  * carrier gain instead */
 317                 if (!link_has_carrier(link))
 318                         break;
 319
 320                 /* AP start event may indicate different properties (e.g. SSID)  */
 321                 r = link_get_wlan_interface(link);
 322                 if (r < 0) {
 323                         log_link_warning_errno(link, r, "Failed to update wireless LAN interface: %m");
 324                         link_enter_failed(link);
 325                         return 0;
 326                 }
 327
 328                 /* If necessary, reconfigure based on those new properties */
 329                 r = link_reconfigure_impl(link, /* force = */ false);
 330                 if (r < 0) {
 331                         log_link_warning_errno(link, r, "Failed to reconfigure interface: %m");
 332                         link_enter_failed(link);
 333                         return 0;
 334                 }
 335
 336                 break;
 337         }
 338
 339         default:
 340                 log_link_debug(link, "nl80211: received %s(%u) message.",
 341                                strna(nl80211_cmd_to_string(cmd)), cmd);
 342         }
 343
 344         return 0;
 345 }