hostap/wpa_supplicant/wnm_sta.c
Jouni Malinen 2049a875bc WNM: Additional BSS Transition Management capability
Add some more functionality for BSS Transition Management:
- advertise support for BSS Transition Management in extended
  capabilities element
- add hostapd.conf parameter bss_transition=1 for enabling support
  for BSS Transition Management
- add "hostapd_cli disassoc_imminent <STA> <num TBTTs>" for sending
  disassociation imminent notifications for testing purposes
- wpa_supplicant: trigger a new scan to find another BSS if the
  current AP indicates disassociation imminent (TODO: the old AP needs
  to be marked to use lower priority to avoid re-selecting it)

Signed-hostap: Jouni Malinen <j@w1.fi>
2012-12-22 20:27:30 +02:00

423 lines
12 KiB
C

/*
* wpa_supplicant - WNM
* Copyright (c) 2011-2012, Qualcomm Atheros, Inc.
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "rsn_supp/wpa.h"
#include "wpa_supplicant_i.h"
#include "driver_i.h"
#include "scan.h"
#define MAX_TFS_IE_LEN 1024
/* get the TFS IE from driver */
static int ieee80211_11_get_tfs_ie(struct wpa_supplicant *wpa_s, u8 *buf,
u16 *buf_len, enum wnm_oper oper)
{
wpa_printf(MSG_DEBUG, "%s: TFS get operation %d", __func__, oper);
return wpa_drv_wnm_oper(wpa_s, oper, wpa_s->bssid, buf, buf_len);
}
/* set the TFS IE to driver */
static int ieee80211_11_set_tfs_ie(struct wpa_supplicant *wpa_s,
const u8 *addr, u8 *buf, u16 *buf_len,
enum wnm_oper oper)
{
wpa_printf(MSG_DEBUG, "%s: TFS set operation %d", __func__, oper);
return wpa_drv_wnm_oper(wpa_s, oper, addr, buf, buf_len);
}
/* MLME-SLEEPMODE.request */
int ieee802_11_send_wnmsleep_req(struct wpa_supplicant *wpa_s,
u8 action, u16 intval, struct wpabuf *tfs_req)
{
struct ieee80211_mgmt *mgmt;
int res;
size_t len;
struct wnm_sleep_element *wnmsleep_ie;
u8 *wnmtfs_ie;
u8 wnmsleep_ie_len;
u16 wnmtfs_ie_len; /* possibly multiple IE(s) */
enum wnm_oper tfs_oper = action == 0 ? WNM_SLEEP_TFS_REQ_IE_ADD :
WNM_SLEEP_TFS_REQ_IE_NONE;
wpa_printf(MSG_DEBUG, "WNM: Request to send WNM-Sleep Mode Request "
"action=%s to " MACSTR,
action == 0 ? "enter" : "exit",
MAC2STR(wpa_s->bssid));
/* WNM-Sleep Mode IE */
wnmsleep_ie_len = sizeof(struct wnm_sleep_element);
wnmsleep_ie = os_zalloc(sizeof(struct wnm_sleep_element));
if (wnmsleep_ie == NULL)
return -1;
wnmsleep_ie->eid = WLAN_EID_WNMSLEEP;
wnmsleep_ie->len = wnmsleep_ie_len - 2;
wnmsleep_ie->action_type = action;
wnmsleep_ie->status = WNM_STATUS_SLEEP_ACCEPT;
wnmsleep_ie->intval = host_to_le16(intval);
wpa_hexdump(MSG_DEBUG, "WNM: WNM-Sleep Mode element",
(u8 *) wnmsleep_ie, wnmsleep_ie_len);
/* TFS IE(s) */
if (tfs_req) {
wnmtfs_ie_len = wpabuf_len(tfs_req);
wnmtfs_ie = os_malloc(wnmtfs_ie_len);
if (wnmtfs_ie == NULL) {
os_free(wnmsleep_ie);
return -1;
}
os_memcpy(wnmtfs_ie, wpabuf_head(tfs_req), wnmtfs_ie_len);
} else {
wnmtfs_ie = os_zalloc(MAX_TFS_IE_LEN);
if (wnmtfs_ie == NULL) {
os_free(wnmsleep_ie);
return -1;
}
if (ieee80211_11_get_tfs_ie(wpa_s, wnmtfs_ie, &wnmtfs_ie_len,
tfs_oper)) {
wnmtfs_ie_len = 0;
os_free(wnmtfs_ie);
wnmtfs_ie = NULL;
}
}
wpa_hexdump(MSG_DEBUG, "WNM: TFS Request element",
(u8 *) wnmtfs_ie, wnmtfs_ie_len);
mgmt = os_zalloc(sizeof(*mgmt) + wnmsleep_ie_len + wnmtfs_ie_len);
if (mgmt == NULL) {
wpa_printf(MSG_DEBUG, "MLME: Failed to allocate buffer for "
"WNM-Sleep Request action frame");
os_free(wnmsleep_ie);
os_free(wnmtfs_ie);
return -1;
}
os_memcpy(mgmt->da, wpa_s->bssid, ETH_ALEN);
os_memcpy(mgmt->sa, wpa_s->own_addr, ETH_ALEN);
os_memcpy(mgmt->bssid, wpa_s->bssid, ETH_ALEN);
mgmt->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
WLAN_FC_STYPE_ACTION);
mgmt->u.action.category = WLAN_ACTION_WNM;
mgmt->u.action.u.wnm_sleep_req.action = WNM_SLEEP_MODE_REQ;
mgmt->u.action.u.wnm_sleep_req.dialogtoken = 1;
os_memcpy(mgmt->u.action.u.wnm_sleep_req.variable, wnmsleep_ie,
wnmsleep_ie_len);
/* copy TFS IE here */
if (wnmtfs_ie_len > 0) {
os_memcpy(mgmt->u.action.u.wnm_sleep_req.variable +
wnmsleep_ie_len, wnmtfs_ie, wnmtfs_ie_len);
}
len = 1 + sizeof(mgmt->u.action.u.wnm_sleep_req) + wnmsleep_ie_len +
wnmtfs_ie_len;
res = wpa_drv_send_action(wpa_s, wpa_s->assoc_freq, 0, wpa_s->bssid,
wpa_s->own_addr, wpa_s->bssid,
&mgmt->u.action.category, len, 0);
if (res < 0)
wpa_printf(MSG_DEBUG, "Failed to send WNM-Sleep Request "
"(action=%d, intval=%d)", action, intval);
os_free(wnmsleep_ie);
os_free(wnmtfs_ie);
os_free(mgmt);
return res;
}
static void wnm_sleep_mode_enter_success(struct wpa_supplicant *wpa_s,
u8 *tfsresp_ie_start,
u8 *tfsresp_ie_end)
{
wpa_drv_wnm_oper(wpa_s, WNM_SLEEP_ENTER_CONFIRM,
wpa_s->bssid, NULL, NULL);
/* remove GTK/IGTK ?? */
/* set the TFS Resp IE(s) */
if (tfsresp_ie_start && tfsresp_ie_end &&
tfsresp_ie_end - tfsresp_ie_start >= 0) {
u16 tfsresp_ie_len;
tfsresp_ie_len = (tfsresp_ie_end + tfsresp_ie_end[1] + 2) -
tfsresp_ie_start;
wpa_printf(MSG_DEBUG, "TFS Resp IE(s) found");
/* pass the TFS Resp IE(s) to driver for processing */
if (ieee80211_11_set_tfs_ie(wpa_s, wpa_s->bssid,
tfsresp_ie_start,
&tfsresp_ie_len,
WNM_SLEEP_TFS_RESP_IE_SET))
wpa_printf(MSG_DEBUG, "WNM: Fail to set TFS Resp IE");
}
}
static void wnm_sleep_mode_exit_success(struct wpa_supplicant *wpa_s,
const u8 *frm, u16 key_len_total)
{
u8 *ptr, *end;
u8 gtk_len;
wpa_drv_wnm_oper(wpa_s, WNM_SLEEP_EXIT_CONFIRM, wpa_s->bssid,
NULL, NULL);
/* Install GTK/IGTK */
/* point to key data field */
ptr = (u8 *) frm + 1 + 1 + 2;
end = ptr + key_len_total;
wpa_hexdump_key(MSG_DEBUG, "WNM: Key Data", ptr, key_len_total);
while (ptr + 1 < end) {
if (ptr + 2 + ptr[1] > end) {
wpa_printf(MSG_DEBUG, "WNM: Invalid Key Data element "
"length");
if (end > ptr) {
wpa_hexdump(MSG_DEBUG, "WNM: Remaining data",
ptr, end - ptr);
}
break;
}
if (*ptr == WNM_SLEEP_SUBELEM_GTK) {
if (ptr[1] < 11 + 5) {
wpa_printf(MSG_DEBUG, "WNM: Too short GTK "
"subelem");
break;
}
gtk_len = *(ptr + 4);
if (ptr[1] < 11 + gtk_len ||
gtk_len < 5 || gtk_len > 32) {
wpa_printf(MSG_DEBUG, "WNM: Invalid GTK "
"subelem");
break;
}
wpa_wnmsleep_install_key(
wpa_s->wpa,
WNM_SLEEP_SUBELEM_GTK,
ptr);
ptr += 13 + gtk_len;
#ifdef CONFIG_IEEE80211W
} else if (*ptr == WNM_SLEEP_SUBELEM_IGTK) {
if (ptr[1] < 2 + 6 + WPA_IGTK_LEN) {
wpa_printf(MSG_DEBUG, "WNM: Too short IGTK "
"subelem");
break;
}
wpa_wnmsleep_install_key(wpa_s->wpa,
WNM_SLEEP_SUBELEM_IGTK, ptr);
ptr += 10 + WPA_IGTK_LEN;
#endif /* CONFIG_IEEE80211W */
} else
break; /* skip the loop */
}
}
static void ieee802_11_rx_wnmsleep_resp(struct wpa_supplicant *wpa_s,
const u8 *frm, int len)
{
/*
* Action [1] | Diaglog Token [1] | Key Data Len [2] | Key Data |
* WNM-Sleep Mode IE | TFS Response IE
*/
u8 *pos = (u8 *) frm; /* point to action field */
u16 key_len_total = le_to_host16(*((u16 *)(frm+2)));
struct wnm_sleep_element *wnmsleep_ie = NULL;
/* multiple TFS Resp IE (assuming consecutive) */
u8 *tfsresp_ie_start = NULL;
u8 *tfsresp_ie_end = NULL;
wpa_printf(MSG_DEBUG, "action=%d token = %d key_len_total = %d",
frm[0], frm[1], key_len_total);
pos += 4 + key_len_total;
if (pos > frm + len) {
wpa_printf(MSG_INFO, "WNM: Too short frame for Key Data field");
return;
}
while (pos - frm < len) {
u8 ie_len = *(pos + 1);
if (pos + 2 + ie_len > frm + len) {
wpa_printf(MSG_INFO, "WNM: Invalid IE len %u", ie_len);
break;
}
wpa_hexdump(MSG_DEBUG, "WNM: Element", pos, 2 + ie_len);
if (*pos == WLAN_EID_WNMSLEEP)
wnmsleep_ie = (struct wnm_sleep_element *) pos;
else if (*pos == WLAN_EID_TFS_RESP) {
if (!tfsresp_ie_start)
tfsresp_ie_start = pos;
tfsresp_ie_end = pos;
} else
wpa_printf(MSG_DEBUG, "EID %d not recognized", *pos);
pos += ie_len + 2;
}
if (!wnmsleep_ie) {
wpa_printf(MSG_DEBUG, "No WNM-Sleep IE found");
return;
}
if (wnmsleep_ie->status == WNM_STATUS_SLEEP_ACCEPT ||
wnmsleep_ie->status == WNM_STATUS_SLEEP_EXIT_ACCEPT_GTK_UPDATE) {
wpa_printf(MSG_DEBUG, "Successfully recv WNM-Sleep Response "
"frame (action=%d, intval=%d)",
wnmsleep_ie->action_type, wnmsleep_ie->intval);
if (wnmsleep_ie->action_type == WNM_SLEEP_MODE_ENTER) {
wnm_sleep_mode_enter_success(wpa_s, tfsresp_ie_start,
tfsresp_ie_end);
} else if (wnmsleep_ie->action_type == WNM_SLEEP_MODE_EXIT) {
wnm_sleep_mode_exit_success(wpa_s, frm, key_len_total);
}
} else {
wpa_printf(MSG_DEBUG, "Reject recv WNM-Sleep Response frame "
"(action=%d, intval=%d)",
wnmsleep_ie->action_type, wnmsleep_ie->intval);
if (wnmsleep_ie->action_type == WNM_SLEEP_MODE_ENTER)
wpa_drv_wnm_oper(wpa_s, WNM_SLEEP_ENTER_FAIL,
wpa_s->bssid, NULL, NULL);
else if (wnmsleep_ie->action_type == WNM_SLEEP_MODE_EXIT)
wpa_drv_wnm_oper(wpa_s, WNM_SLEEP_EXIT_FAIL,
wpa_s->bssid, NULL, NULL);
}
}
static void wnm_send_bss_transition_mgmt_resp(struct wpa_supplicant *wpa_s,
u8 dialog_token, u8 status,
u8 delay, const u8 *target_bssid)
{
u8 buf[1000], *pos;
struct ieee80211_mgmt *mgmt;
size_t len;
wpa_printf(MSG_DEBUG, "WNM: Send BSS Transition Management Response "
"to " MACSTR " dialog_token=%u status=%u delay=%d",
MAC2STR(wpa_s->bssid), dialog_token, status, delay);
mgmt = (struct ieee80211_mgmt *) buf;
os_memset(&buf, 0, sizeof(buf));
os_memcpy(mgmt->da, wpa_s->bssid, ETH_ALEN);
os_memcpy(mgmt->sa, wpa_s->own_addr, ETH_ALEN);
os_memcpy(mgmt->bssid, wpa_s->bssid, ETH_ALEN);
mgmt->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
WLAN_FC_STYPE_ACTION);
mgmt->u.action.category = WLAN_ACTION_WNM;
mgmt->u.action.u.bss_tm_resp.action = WNM_BSS_TRANS_MGMT_RESP;
mgmt->u.action.u.bss_tm_resp.dialog_token = dialog_token;
mgmt->u.action.u.bss_tm_resp.status_code = status;
mgmt->u.action.u.bss_tm_resp.bss_termination_delay = delay;
pos = mgmt->u.action.u.bss_tm_resp.variable;
if (target_bssid) {
os_memcpy(pos, target_bssid, ETH_ALEN);
pos += ETH_ALEN;
}
len = pos - (u8 *) &mgmt->u.action.category;
wpa_drv_send_action(wpa_s, wpa_s->assoc_freq, 0, wpa_s->bssid,
wpa_s->own_addr, wpa_s->bssid,
&mgmt->u.action.category, len, 0);
}
static void ieee802_11_rx_bss_trans_mgmt_req(struct wpa_supplicant *wpa_s,
const u8 *pos, const u8 *end,
int reply)
{
u8 dialog_token;
u8 mode;
u16 disassoc_timer;
if (pos + 5 > end)
return;
dialog_token = pos[0];
mode = pos[1];
disassoc_timer = WPA_GET_LE16(pos + 2);
wpa_printf(MSG_DEBUG, "WNM: BSS Transition Management Request: "
"dialog_token=%u request_mode=0x%x "
"disassoc_timer=%u validity_interval=%u",
dialog_token, mode, disassoc_timer, pos[4]);
pos += 5;
if (mode & 0x08)
pos += 12; /* BSS Termination Duration */
if (mode & 0x10) {
char url[256];
if (pos + 1 > end || pos + 1 + pos[0] > end) {
wpa_printf(MSG_DEBUG, "WNM: Invalid BSS Transition "
"Management Request (URL)");
return;
}
os_memcpy(url, pos + 1, pos[0]);
url[pos[0]] = '\0';
wpa_msg(wpa_s, MSG_INFO, "WNM: ESS Disassociation Imminent - "
"session_info_url=%s", url);
}
if (mode & 0x04) {
wpa_msg(wpa_s, MSG_INFO, "WNM: Disassociation Imminent - "
"Disassociation Timer %u", disassoc_timer);
if (disassoc_timer && !wpa_s->scanning) {
/* TODO: mark current BSS less preferred for
* selection */
wpa_printf(MSG_DEBUG, "Trying to find another BSS");
wpa_supplicant_req_scan(wpa_s, 0, 0);
}
}
if (reply) {
/* TODO: add support for reporting Accept */
wnm_send_bss_transition_mgmt_resp(wpa_s, dialog_token,
1 /* Reject - unspecified */,
0, NULL);
}
}
void ieee802_11_rx_wnm_action(struct wpa_supplicant *wpa_s,
struct rx_action *action)
{
const u8 *pos, *end;
u8 act;
if (action->data == NULL || action->len == 0)
return;
pos = action->data;
end = pos + action->len;
act = *pos++;
wpa_printf(MSG_DEBUG, "WNM: RX action %u from " MACSTR,
act, MAC2STR(action->sa));
if (wpa_s->wpa_state < WPA_ASSOCIATED ||
os_memcmp(action->sa, wpa_s->bssid, ETH_ALEN) != 0) {
wpa_printf(MSG_DEBUG, "WNM: Ignore unexpected WNM Action "
"frame");
return;
}
switch (act) {
case WNM_BSS_TRANS_MGMT_REQ:
ieee802_11_rx_bss_trans_mgmt_req(wpa_s, pos, end,
!(action->da[0] & 0x01));
break;
case WNM_SLEEP_MODE_RESP:
ieee802_11_rx_wnmsleep_resp(wpa_s, action->data, action->len);
break;
default:
break;
}
}