/*
* wpa_supplicant - Off-channel Action frame TX/RX
* Copyright (c) 2009-2010, Atheros Communications
* Copyright (c) 2011, Qualcomm Atheros
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "includes.h"
#include "common.h"
#include "utils/eloop.h"
#include "wpa_supplicant_i.h"
#include "driver_i.h"
#include "offchannel.h"
static struct wpa_supplicant *
wpas_get_tx_interface(struct wpa_supplicant *wpa_s, const u8 *src)
{
struct wpa_supplicant *iface;
if (os_memcmp(src, wpa_s->own_addr, ETH_ALEN) == 0)
return wpa_s;
/*
* Try to find a group interface that matches with the source address.
*/
iface = wpa_s->global->ifaces;
while (iface) {
if (os_memcmp(wpa_s->pending_action_src,
iface->own_addr, ETH_ALEN) == 0)
break;
iface = iface->next;
}
if (iface) {
wpa_printf(MSG_DEBUG, "P2P: Use group interface %s "
"instead of interface %s for Action TX",
iface->ifname, wpa_s->ifname);
return iface;
}
return wpa_s;
}
static void wpas_send_action_cb(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
struct wpa_supplicant *iface;
int res;
int without_roc;
without_roc = wpa_s->pending_action_without_roc;
wpa_s->pending_action_without_roc = 0;
wpa_printf(MSG_DEBUG, "Off-channel: Send Action callback "
"(without_roc=%d pending_action_tx=%p)",
without_roc, wpa_s->pending_action_tx);
if (wpa_s->pending_action_tx == NULL)
return;
/*
* This call is likely going to be on the P2P device instance if the
* driver uses a separate interface for that purpose. However, some
* Action frames are actually sent within a P2P Group and when that is
* the case, we need to follow power saving (e.g., GO buffering the
* frame for a client in PS mode or a client following the advertised
* NoA from its GO). To make that easier for the driver, select the
* correct group interface here.
*/
iface = wpas_get_tx_interface(wpa_s, wpa_s->pending_action_src);
if (wpa_s->off_channel_freq != wpa_s->pending_action_freq &&
wpa_s->pending_action_freq != 0 &&
wpa_s->pending_action_freq != iface->assoc_freq) {
wpa_printf(MSG_DEBUG, "Off-channel: Pending Action frame TX "
"waiting for another freq=%u (off_channel_freq=%u "
"assoc_freq=%u)",
wpa_s->pending_action_freq,
wpa_s->off_channel_freq,
iface->assoc_freq);
if (without_roc && wpa_s->off_channel_freq == 0) {
/*
* We may get here if wpas_send_action() found us to be
* on the correct channel, but remain-on-channel cancel
* event was received before getting here.
*/
wpa_printf(MSG_DEBUG, "Off-channel: Schedule "
"remain-on-channel to send Action frame");
if (wpa_drv_remain_on_channel(
wpa_s, wpa_s->pending_action_freq, 200) <
0) {
wpa_printf(MSG_DEBUG, "Off-channel: Failed to "
"request driver to remain on "
"channel (%u MHz) for Action Frame "
"TX", wpa_s->pending_action_freq);
} else {
wpa_s->off_channel_freq = 0;
wpa_s->roc_waiting_drv_freq =
wpa_s->pending_action_freq;
}
}
return;
}
wpa_printf(MSG_DEBUG, "Off-channel: Sending pending Action frame to "
MACSTR " using interface %s",
MAC2STR(wpa_s->pending_action_dst), iface->ifname);
res = wpa_drv_send_action(iface, wpa_s->pending_action_freq, 0,
wpa_s->pending_action_dst,
wpa_s->pending_action_src,
wpa_s->pending_action_bssid,
wpabuf_head(wpa_s->pending_action_tx),
wpabuf_len(wpa_s->pending_action_tx),
wpa_s->pending_action_no_cck);
if (res) {
wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the "
"pending Action frame");
/*
* Use fake TX status event to allow state machines to
* continue.
*/
offchannel_send_action_tx_status(
wpa_s, wpa_s->pending_action_dst,
wpabuf_head(wpa_s->pending_action_tx),
wpabuf_len(wpa_s->pending_action_tx),
OFFCHANNEL_SEND_ACTION_FAILED);
}
}
/**
* offchannel_send_action_tx_status - TX status callback
* @wpa_s: Pointer to wpa_supplicant data
* @dst: Destination MAC address of the transmitted Action frame
* @data: Transmitted frame payload
* @data_len: Length of @data in bytes
* @result: TX status
*
* This function is called whenever the driver indicates a TX status event for
* a frame sent by offchannel_send_action() using wpa_drv_send_action().
*/
void offchannel_send_action_tx_status(
struct wpa_supplicant *wpa_s, const u8 *dst, const u8 *data,
size_t data_len, enum offchannel_send_action_result result)
{
if (wpa_s->pending_action_tx == NULL) {
wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
"no pending operation");
return;
}
if (os_memcmp(dst, wpa_s->pending_action_dst, ETH_ALEN) != 0) {
wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
"unknown destination address");
return;
}
wpabuf_free(wpa_s->pending_action_tx);
wpa_s->pending_action_tx = NULL;
wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p",
result, wpa_s->pending_action_tx_status_cb);
if (wpa_s->pending_action_tx_status_cb) {
wpa_s->pending_action_tx_status_cb(
wpa_s, wpa_s->pending_action_freq,
wpa_s->pending_action_dst, wpa_s->pending_action_src,
wpa_s->pending_action_bssid,
data, data_len, result);
}
}
/**
* offchannel_send_action - Request off-channel Action frame TX
* @wpa_s: Pointer to wpa_supplicant data
* @freq: The frequency in MHz indicating the channel on which the frame is to
* transmitted or 0 for the current channel (only if associated)
* @dst: Action frame destination MAC address
* @src: Action frame source MAC address
* @bssid: Action frame BSSID
* @buf: Frame to transmit starting from the Category field
* @len: Length of @buf in bytes
* @wait_time: Wait time for response in milliseconds
* @tx_cb: Callback function for indicating TX status or %NULL for now callback
* @no_cck: Whether CCK rates are to be disallowed for TX rate selection
* Returns: 0 on success or -1 on failure
*
* This function is used to request an Action frame to be transmitted on the
* current operating channel or on another channel (off-channel). The actual
* frame transmission will be delayed until the driver is ready on the specified
* channel. The @wait_time parameter can be used to request the driver to remain
* awake on the channel to wait for a response.
*/
int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
const u8 *dst, const u8 *src, const u8 *bssid,
const u8 *buf, size_t len, unsigned int wait_time,
void (*tx_cb)(struct wpa_supplicant *wpa_s,
unsigned int freq, const u8 *dst,
const u8 *src, const u8 *bssid,
const u8 *data, size_t data_len,
enum offchannel_send_action_result
result),
int no_cck)
{
wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst="
MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d",
freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid),
(int) len);
wpa_s->pending_action_tx_status_cb = tx_cb;
if (wpa_s->pending_action_tx) {
wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
"frame TX to " MACSTR,
MAC2STR(wpa_s->pending_action_dst));
wpabuf_free(wpa_s->pending_action_tx);
}
wpa_s->pending_action_tx = wpabuf_alloc(len);
if (wpa_s->pending_action_tx == NULL) {
wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action "
"frame TX buffer (len=%llu)",
(unsigned long long) len);
return -1;
}
wpabuf_put_data(wpa_s->pending_action_tx, buf, len);
os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN);
os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN);
os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN);
wpa_s->pending_action_freq = freq;
wpa_s->pending_action_no_cck = no_cck;
if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) {
struct wpa_supplicant *iface;
iface = wpas_get_tx_interface(wpa_s,
wpa_s->pending_action_src);
wpa_s->action_tx_wait_time = wait_time;
return wpa_drv_send_action(
iface, wpa_s->pending_action_freq,
wait_time, wpa_s->pending_action_dst,
wpa_s->pending_action_src, wpa_s->pending_action_bssid,
wpabuf_head(wpa_s->pending_action_tx),
wpabuf_len(wpa_s->pending_action_tx),
wpa_s->pending_action_no_cck);
}
if (freq) {
struct wpa_supplicant *tx_iface;
tx_iface = wpas_get_tx_interface(wpa_s, src);
if (tx_iface->assoc_freq == freq) {
wpa_printf(MSG_DEBUG, "Off-channel: Already on "
"requested channel (TX interface operating "
"channel)");
freq = 0;
}
}
if (wpa_s->off_channel_freq == freq || freq == 0) {
wpa_printf(MSG_DEBUG, "Off-channel: Already on requested "
"channel; send Action frame immediately");
/* TODO: Would there ever be need to extend the current
* duration on the channel? */
wpa_s->pending_action_without_roc = 1;
eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL);
return 0;
}
wpa_s->pending_action_without_roc = 0;
if (wpa_s->roc_waiting_drv_freq == freq) {
wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for "
"driver to get to frequency %u MHz; continue "
"waiting to send the Action frame", freq);
return 0;
}
wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be "
"transmitted once the driver gets to the requested "
"channel");
if (wait_time > wpa_s->max_remain_on_chan)
wait_time = wpa_s->max_remain_on_chan;
else if (wait_time == 0)
wait_time = 20;
if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) {
wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver "
"to remain on channel (%u MHz) for Action "
"Frame TX", freq);
return -1;
}
wpa_s->off_channel_freq = 0;
wpa_s->roc_waiting_drv_freq = freq;
return 0;
}
/**
* offchannel_send_send_action_done - Notify completion of Action frame sequence
* @wpa_s: Pointer to wpa_supplicant data
*
* This function can be used to cancel a wait for additional response frames on
* the channel that was used with offchannel_send_action().
*/
void offchannel_send_action_done(struct wpa_supplicant *wpa_s)
{
wpa_printf(MSG_DEBUG, "Off-channel: Action frame sequence done "
"notification");
wpabuf_free(wpa_s->pending_action_tx);
wpa_s->pending_action_tx = NULL;
if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX &&
wpa_s->action_tx_wait_time)
wpa_drv_send_action_cancel_wait(wpa_s);
if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) {
wpa_drv_cancel_remain_on_channel(wpa_s);
wpa_s->off_channel_freq = 0;
wpa_s->roc_waiting_drv_freq = 0;
}
}
/**
* offchannel_remain_on_channel_cb - Remain-on-channel callback function
* @wpa_s: Pointer to wpa_supplicant data
* @freq: Frequency (in MHz) of the selected channel
* @duration: Duration of the remain-on-channel operation in milliseconds
*
* This function is called whenever the driver notifies beginning of a
* remain-on-channel operation.
*/
void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
unsigned int freq, unsigned int duration)
{
wpa_s->roc_waiting_drv_freq = 0;
wpa_s->off_channel_freq = freq;
wpas_send_action_cb(wpa_s, NULL);
}
/**
* offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback
* @wpa_s: Pointer to wpa_supplicant data
* @freq: Frequency (in MHz) of the selected channel
*
* This function is called whenever the driver notifies termination of a
* remain-on-channel operation.
*/
void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
unsigned int freq)
{
wpa_s->off_channel_freq = 0;
}
/**
* offchannel_pending_action_tx - Check whether there is a pending Action TX
* @wpa_s: Pointer to wpa_supplicant data
* Returns: Pointer to pending frame or %NULL if no pending operation
*
* This function can be used to check whether there is a pending Action frame TX
* operation. The returned pointer should be used only for checking whether it
* is %NULL (no pending frame) or to print the pointer value in debug
* information (i.e., the pointer should not be dereferenced).
*/
const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s)
{
return wpa_s->pending_action_tx;
}
/**
* offchannel_clear_pending_action_tx - Clear pending Action frame TX
* @wpa_s: Pointer to wpa_supplicant data
*/
void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s)
{
wpabuf_free(wpa_s->pending_action_tx);
wpa_s->pending_action_tx = NULL;
}
/**
* offchannel_deinit - Deinit off-channel operations
* @wpa_s: Pointer to wpa_supplicant data
*
* This function is used to free up any allocated resources for off-channel
* operations.
*/
void offchannel_deinit(struct wpa_supplicant *wpa_s)
{
offchannel_clear_pending_action_tx(wpa_s);
eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
}