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d4b951f31b
If the offchannel TX frame command was offloaded to the driver in offchannel_send_action(), we must not send another copy of the frame if a remain-on-channel event happens to be delivered between this TX command and the matching TX status event. It was possible for the duplicated frame to cause problems, e.g., with P2P invitation exchange if the same Invitation Request frame got sent twice and only the first one getting accepted by the peer. Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
421 lines
14 KiB
C
421 lines
14 KiB
C
/*
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* wpa_supplicant - Off-channel Action frame TX/RX
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* Copyright (c) 2009-2010, Atheros Communications
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* Copyright (c) 2011, Qualcomm Atheros
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*
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* This software may be distributed under the terms of the BSD license.
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* See README for more details.
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*/
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#include "includes.h"
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#include "common.h"
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#include "utils/eloop.h"
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#include "wpa_supplicant_i.h"
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#include "driver_i.h"
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#include "offchannel.h"
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static struct wpa_supplicant *
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wpas_get_tx_interface(struct wpa_supplicant *wpa_s, const u8 *src)
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{
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struct wpa_supplicant *iface;
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if (os_memcmp(src, wpa_s->own_addr, ETH_ALEN) == 0)
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return wpa_s;
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/*
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* Try to find a group interface that matches with the source address.
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*/
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iface = wpa_s->global->ifaces;
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while (iface) {
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if (os_memcmp(wpa_s->pending_action_src,
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iface->own_addr, ETH_ALEN) == 0)
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break;
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iface = iface->next;
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}
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if (iface) {
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wpa_printf(MSG_DEBUG, "P2P: Use group interface %s "
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"instead of interface %s for Action TX",
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iface->ifname, wpa_s->ifname);
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return iface;
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}
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return wpa_s;
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}
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static void wpas_send_action_cb(void *eloop_ctx, void *timeout_ctx)
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{
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struct wpa_supplicant *wpa_s = eloop_ctx;
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struct wpa_supplicant *iface;
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int res;
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int without_roc;
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without_roc = wpa_s->pending_action_without_roc;
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wpa_s->pending_action_without_roc = 0;
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wpa_printf(MSG_DEBUG,
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"Off-channel: Send Action callback (without_roc=%d pending_action_tx=%p pending_action_tx_done=%d)",
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without_roc, wpa_s->pending_action_tx,
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!!wpa_s->pending_action_tx_done);
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if (wpa_s->pending_action_tx == NULL || wpa_s->pending_action_tx_done)
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return;
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/*
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* This call is likely going to be on the P2P device instance if the
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* driver uses a separate interface for that purpose. However, some
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* Action frames are actually sent within a P2P Group and when that is
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* the case, we need to follow power saving (e.g., GO buffering the
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* frame for a client in PS mode or a client following the advertised
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* NoA from its GO). To make that easier for the driver, select the
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* correct group interface here.
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*/
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iface = wpas_get_tx_interface(wpa_s, wpa_s->pending_action_src);
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if (wpa_s->off_channel_freq != wpa_s->pending_action_freq &&
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wpa_s->pending_action_freq != 0 &&
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wpa_s->pending_action_freq != iface->assoc_freq) {
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wpa_printf(MSG_DEBUG, "Off-channel: Pending Action frame TX "
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"waiting for another freq=%u (off_channel_freq=%u "
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"assoc_freq=%u)",
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wpa_s->pending_action_freq,
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wpa_s->off_channel_freq,
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iface->assoc_freq);
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if (without_roc && wpa_s->off_channel_freq == 0) {
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/*
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* We may get here if wpas_send_action() found us to be
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* on the correct channel, but remain-on-channel cancel
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* event was received before getting here.
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*/
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wpa_printf(MSG_DEBUG, "Off-channel: Schedule "
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"remain-on-channel to send Action frame");
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if (wpa_drv_remain_on_channel(
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wpa_s, wpa_s->pending_action_freq, 200) <
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0) {
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wpa_printf(MSG_DEBUG, "Off-channel: Failed to "
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"request driver to remain on "
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"channel (%u MHz) for Action Frame "
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"TX", wpa_s->pending_action_freq);
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} else {
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wpa_s->off_channel_freq = 0;
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wpa_s->roc_waiting_drv_freq =
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wpa_s->pending_action_freq;
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}
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}
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return;
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}
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wpa_printf(MSG_DEBUG, "Off-channel: Sending pending Action frame to "
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MACSTR " using interface %s",
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MAC2STR(wpa_s->pending_action_dst), iface->ifname);
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res = wpa_drv_send_action(iface, wpa_s->pending_action_freq, 0,
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wpa_s->pending_action_dst,
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wpa_s->pending_action_src,
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wpa_s->pending_action_bssid,
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wpabuf_head(wpa_s->pending_action_tx),
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wpabuf_len(wpa_s->pending_action_tx),
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wpa_s->pending_action_no_cck);
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if (res) {
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wpa_printf(MSG_DEBUG, "Off-channel: Failed to send the "
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"pending Action frame");
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/*
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* Use fake TX status event to allow state machines to
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* continue.
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*/
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offchannel_send_action_tx_status(
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wpa_s, wpa_s->pending_action_dst,
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wpabuf_head(wpa_s->pending_action_tx),
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wpabuf_len(wpa_s->pending_action_tx),
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OFFCHANNEL_SEND_ACTION_FAILED);
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}
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}
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/**
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* offchannel_send_action_tx_status - TX status callback
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* @wpa_s: Pointer to wpa_supplicant data
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* @dst: Destination MAC address of the transmitted Action frame
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* @data: Transmitted frame payload
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* @data_len: Length of @data in bytes
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* @result: TX status
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*
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* This function is called whenever the driver indicates a TX status event for
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* a frame sent by offchannel_send_action() using wpa_drv_send_action().
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*/
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void offchannel_send_action_tx_status(
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struct wpa_supplicant *wpa_s, const u8 *dst, const u8 *data,
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size_t data_len, enum offchannel_send_action_result result)
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{
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if (wpa_s->pending_action_tx == NULL) {
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wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
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"no pending operation");
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return;
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}
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if (os_memcmp(dst, wpa_s->pending_action_dst, ETH_ALEN) != 0) {
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wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
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"unknown destination address");
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return;
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}
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/* Accept report only if the contents of the frame matches */
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if (data_len - wpabuf_len(wpa_s->pending_action_tx) != 24 ||
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os_memcmp(data + 24, wpabuf_head(wpa_s->pending_action_tx),
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wpabuf_len(wpa_s->pending_action_tx)) != 0) {
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wpa_printf(MSG_DEBUG, "Off-channel: Ignore Action TX status - "
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"mismatching contents with pending frame");
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wpa_hexdump(MSG_MSGDUMP, "TX status frame data",
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data, data_len);
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wpa_hexdump_buf(MSG_MSGDUMP, "Pending TX frame",
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wpa_s->pending_action_tx);
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return;
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}
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wpa_printf(MSG_DEBUG, "Off-channel: Delete matching pending action frame");
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wpabuf_free(wpa_s->pending_action_tx);
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wpa_s->pending_action_tx = NULL;
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wpa_printf(MSG_DEBUG, "Off-channel: TX status result=%d cb=%p",
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result, wpa_s->pending_action_tx_status_cb);
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if (wpa_s->pending_action_tx_status_cb) {
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wpa_s->pending_action_tx_status_cb(
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wpa_s, wpa_s->pending_action_freq,
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wpa_s->pending_action_dst, wpa_s->pending_action_src,
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wpa_s->pending_action_bssid,
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data, data_len, result);
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}
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}
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/**
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* offchannel_send_action - Request off-channel Action frame TX
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* @wpa_s: Pointer to wpa_supplicant data
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* @freq: The frequency in MHz indicating the channel on which the frame is to
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* transmitted or 0 for the current channel (only if associated)
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* @dst: Action frame destination MAC address
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* @src: Action frame source MAC address
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* @bssid: Action frame BSSID
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* @buf: Frame to transmit starting from the Category field
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* @len: Length of @buf in bytes
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* @wait_time: Wait time for response in milliseconds
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* @tx_cb: Callback function for indicating TX status or %NULL for now callback
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* @no_cck: Whether CCK rates are to be disallowed for TX rate selection
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* Returns: 0 on success or -1 on failure
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*
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* This function is used to request an Action frame to be transmitted on the
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* current operating channel or on another channel (off-channel). The actual
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* frame transmission will be delayed until the driver is ready on the specified
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* channel. The @wait_time parameter can be used to request the driver to remain
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* awake on the channel to wait for a response.
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*/
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int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
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const u8 *dst, const u8 *src, const u8 *bssid,
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const u8 *buf, size_t len, unsigned int wait_time,
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void (*tx_cb)(struct wpa_supplicant *wpa_s,
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unsigned int freq, const u8 *dst,
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const u8 *src, const u8 *bssid,
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const u8 *data, size_t data_len,
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enum offchannel_send_action_result
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result),
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int no_cck)
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{
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wpa_printf(MSG_DEBUG, "Off-channel: Send action frame: freq=%d dst="
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MACSTR " src=" MACSTR " bssid=" MACSTR " len=%d",
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freq, MAC2STR(dst), MAC2STR(src), MAC2STR(bssid),
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(int) len);
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wpa_s->pending_action_tx_status_cb = tx_cb;
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if (wpa_s->pending_action_tx) {
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wpa_printf(MSG_DEBUG, "Off-channel: Dropped pending Action "
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"frame TX to " MACSTR,
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MAC2STR(wpa_s->pending_action_dst));
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wpabuf_free(wpa_s->pending_action_tx);
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}
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wpa_s->pending_action_tx_done = 0;
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wpa_s->pending_action_tx = wpabuf_alloc(len);
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if (wpa_s->pending_action_tx == NULL) {
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wpa_printf(MSG_DEBUG, "Off-channel: Failed to allocate Action "
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"frame TX buffer (len=%llu)",
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(unsigned long long) len);
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return -1;
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}
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wpabuf_put_data(wpa_s->pending_action_tx, buf, len);
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os_memcpy(wpa_s->pending_action_src, src, ETH_ALEN);
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os_memcpy(wpa_s->pending_action_dst, dst, ETH_ALEN);
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os_memcpy(wpa_s->pending_action_bssid, bssid, ETH_ALEN);
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wpa_s->pending_action_freq = freq;
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wpa_s->pending_action_no_cck = no_cck;
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if (freq != 0 && wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX) {
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struct wpa_supplicant *iface;
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int ret;
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iface = wpas_get_tx_interface(wpa_s,
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wpa_s->pending_action_src);
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wpa_s->action_tx_wait_time = wait_time;
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ret = wpa_drv_send_action(
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iface, wpa_s->pending_action_freq,
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wait_time, wpa_s->pending_action_dst,
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wpa_s->pending_action_src, wpa_s->pending_action_bssid,
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wpabuf_head(wpa_s->pending_action_tx),
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wpabuf_len(wpa_s->pending_action_tx),
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wpa_s->pending_action_no_cck);
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if (ret == 0)
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wpa_s->pending_action_tx_done = 1;
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return ret;
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}
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if (freq) {
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struct wpa_supplicant *tx_iface;
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tx_iface = wpas_get_tx_interface(wpa_s, src);
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if (tx_iface->assoc_freq == freq) {
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wpa_printf(MSG_DEBUG, "Off-channel: Already on "
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"requested channel (TX interface operating "
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"channel)");
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freq = 0;
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}
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}
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if (wpa_s->off_channel_freq == freq || freq == 0) {
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wpa_printf(MSG_DEBUG, "Off-channel: Already on requested "
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"channel; send Action frame immediately");
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/* TODO: Would there ever be need to extend the current
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* duration on the channel? */
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wpa_s->pending_action_without_roc = 1;
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eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
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eloop_register_timeout(0, 0, wpas_send_action_cb, wpa_s, NULL);
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return 0;
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}
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wpa_s->pending_action_without_roc = 0;
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if (wpa_s->roc_waiting_drv_freq == freq) {
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wpa_printf(MSG_DEBUG, "Off-channel: Already waiting for "
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"driver to get to frequency %u MHz; continue "
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"waiting to send the Action frame", freq);
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return 0;
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}
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wpa_printf(MSG_DEBUG, "Off-channel: Schedule Action frame to be "
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"transmitted once the driver gets to the requested "
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"channel");
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if (wait_time > wpa_s->max_remain_on_chan)
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wait_time = wpa_s->max_remain_on_chan;
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else if (wait_time == 0)
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wait_time = 20;
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if (wpa_drv_remain_on_channel(wpa_s, freq, wait_time) < 0) {
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wpa_printf(MSG_DEBUG, "Off-channel: Failed to request driver "
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"to remain on channel (%u MHz) for Action "
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"Frame TX", freq);
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return -1;
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}
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wpa_s->off_channel_freq = 0;
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wpa_s->roc_waiting_drv_freq = freq;
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return 0;
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}
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/**
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* offchannel_send_send_action_done - Notify completion of Action frame sequence
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* @wpa_s: Pointer to wpa_supplicant data
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*
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* This function can be used to cancel a wait for additional response frames on
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* the channel that was used with offchannel_send_action().
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*/
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void offchannel_send_action_done(struct wpa_supplicant *wpa_s)
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{
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wpa_printf(MSG_DEBUG, "Off-channel: Action frame sequence done "
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"notification");
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wpabuf_free(wpa_s->pending_action_tx);
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wpa_s->pending_action_tx = NULL;
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if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_OFFCHANNEL_TX &&
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wpa_s->action_tx_wait_time)
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wpa_drv_send_action_cancel_wait(wpa_s);
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if (wpa_s->off_channel_freq || wpa_s->roc_waiting_drv_freq) {
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wpa_drv_cancel_remain_on_channel(wpa_s);
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wpa_s->off_channel_freq = 0;
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wpa_s->roc_waiting_drv_freq = 0;
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}
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}
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/**
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* offchannel_remain_on_channel_cb - Remain-on-channel callback function
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* @wpa_s: Pointer to wpa_supplicant data
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* @freq: Frequency (in MHz) of the selected channel
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* @duration: Duration of the remain-on-channel operation in milliseconds
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*
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* This function is called whenever the driver notifies beginning of a
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* remain-on-channel operation.
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*/
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void offchannel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
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unsigned int freq, unsigned int duration)
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{
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wpa_s->roc_waiting_drv_freq = 0;
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wpa_s->off_channel_freq = freq;
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wpas_send_action_cb(wpa_s, NULL);
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}
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/**
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* offchannel_cancel_remain_on_channel_cb - Remain-on-channel stopped callback
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* @wpa_s: Pointer to wpa_supplicant data
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* @freq: Frequency (in MHz) of the selected channel
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*
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* This function is called whenever the driver notifies termination of a
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* remain-on-channel operation.
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*/
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void offchannel_cancel_remain_on_channel_cb(struct wpa_supplicant *wpa_s,
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unsigned int freq)
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{
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wpa_s->off_channel_freq = 0;
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}
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/**
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* offchannel_pending_action_tx - Check whether there is a pending Action TX
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* @wpa_s: Pointer to wpa_supplicant data
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* Returns: Pointer to pending frame or %NULL if no pending operation
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*
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* This function can be used to check whether there is a pending Action frame TX
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* operation. The returned pointer should be used only for checking whether it
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* is %NULL (no pending frame) or to print the pointer value in debug
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* information (i.e., the pointer should not be dereferenced).
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*/
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const void * offchannel_pending_action_tx(struct wpa_supplicant *wpa_s)
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{
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return wpa_s->pending_action_tx;
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}
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/**
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* offchannel_clear_pending_action_tx - Clear pending Action frame TX
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* @wpa_s: Pointer to wpa_supplicant data
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*/
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void offchannel_clear_pending_action_tx(struct wpa_supplicant *wpa_s)
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{
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wpabuf_free(wpa_s->pending_action_tx);
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wpa_s->pending_action_tx = NULL;
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}
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/**
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* offchannel_deinit - Deinit off-channel operations
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* @wpa_s: Pointer to wpa_supplicant data
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*
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* This function is used to free up any allocated resources for off-channel
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* operations.
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*/
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void offchannel_deinit(struct wpa_supplicant *wpa_s)
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{
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offchannel_clear_pending_action_tx(wpa_s);
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eloop_cancel_timeout(wpas_send_action_cb, wpa_s, NULL);
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}
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