Amazing-Mirror/fragattacks
1
0
Fork 0
mirror of https://github.com/vanhoefm/fragattacks.git synced 2024-12-02 04:08:26 -05:00
Code Issues Projects Releases Wiki Activity
16e38f2e34
fragattacks/src/p2p/p2p_go_neg.c
Jouni Malinen 13ece96f70 P2P: Improve robustness against lost ctrl::ack frames 
P2P includes two use cases where one of the devices is going to start a
group and likely change channels immediately after processing a frame.
This operation may be fast enough to make the device leave the current
channel before the peer has completed layer 2 retransmission of the
frame in case the ctrl::ack frame was lost. This can result in the peer
not getting TX status success notification.

For GO Negotiation Confirm frame, p2p_go_neg_conf_cb() has a workaround
that ignores the TX status failure and will continue with the group
formation with the assumption that the peer actually received the frame
even though we did not receive ctrl::ack. For Invitation Response frame
to re-invoke a persistent group, no such workaround is used in
p2p_invitation_resp_cb(). Consequently, TX status failure due to lost
ctrl::ack frame results in one of the peers not starting the group.

Increase the likelihood of layer 2 retransmission getting acknowledged
and ctrl::ack being received by waiting a short duration after having
processed the GO Negotiation Confirm and Invitation Response frames for
the re-invocation case. For the former, use 20 ms wait since this case
has been worked around in deployed devices. For the latter, use 50 ms
wait to get even higher likelihood of getting ctrl::ack through since
deployed devices (and the current wpa_supplicant implementation) do not
have a workaround to ignore TX status failure.

20 ms is long enough to include at least couple of retries and that
should increase likelihood of getting ctrl::ack through quite a bit. The
longer 50 ms wait is likely to include full set of layer 2 retries.

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
2012-10-13 17:33:16 +03:00

1208 lines
34 KiB
C
Raw Blame History

/*
* Wi-Fi Direct - P2P Group Owner Negotiation
* Copyright (c) 2009-2010, Atheros Communications
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "includes.h"
#include "common.h"
#include "common/ieee802_11_defs.h"
#include "wps/wps_defs.h"
#include "p2p_i.h"
#include "p2p.h"
static int p2p_go_det(u8 own_intent, u8 peer_value)
{
u8 peer_intent = peer_value >> 1;
if (own_intent == peer_intent) {
if (own_intent == P2P_MAX_GO_INTENT)
return -1; /* both devices want to become GO */
/* Use tie breaker bit to determine GO */
return (peer_value & 0x01) ? 0 : 1;
}
return own_intent > peer_intent;
}
int p2p_peer_channels_check(struct p2p_data *p2p, struct p2p_channels *own,
struct p2p_device *dev,
const u8 *channel_list, size_t channel_list_len)
{
const u8 *pos, *end;
struct p2p_channels *ch;
size_t channels;
struct p2p_channels intersection;
ch = &dev->channels;
os_memset(ch, 0, sizeof(*ch));
pos = channel_list;
end = channel_list + channel_list_len;
if (end - pos < 3)
return -1;
os_memcpy(dev->country, pos, 3);
wpa_hexdump_ascii(MSG_DEBUG, "P2P: Peer country", pos, 3);
if (pos[2] != 0x04 && os_memcmp(pos, p2p->cfg->country, 2) != 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_INFO,
"P2P: Mismatching country (ours=%c%c peer's=%c%c)",
p2p->cfg->country[0], p2p->cfg->country[1],
pos[0], pos[1]);
return -1;
}
pos += 3;
while (pos + 2 < end) {
struct p2p_reg_class *cl = &ch->reg_class[ch->reg_classes];
cl->reg_class = *pos++;
if (pos + 1 + pos[0] > end) {
wpa_msg(p2p->cfg->msg_ctx, MSG_INFO,
"P2P: Invalid peer Channel List");
return -1;
}
channels = *pos++;
cl->channels = channels > P2P_MAX_REG_CLASS_CHANNELS ?
P2P_MAX_REG_CLASS_CHANNELS : channels;
os_memcpy(cl->channel, pos, cl->channels);
pos += channels;
ch->reg_classes++;
if (ch->reg_classes == P2P_MAX_REG_CLASSES)
break;
}
p2p_channels_intersect(own, &dev->channels, &intersection);
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Own reg_classes %d "
"peer reg_classes %d intersection reg_classes %d",
(int) own->reg_classes,
(int) dev->channels.reg_classes,
(int) intersection.reg_classes);
if (intersection.reg_classes == 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_INFO,
"P2P: No common channels found");
return -1;
}
return 0;
}
static int p2p_peer_channels(struct p2p_data *p2p, struct p2p_device *dev,
const u8 *channel_list, size_t channel_list_len)
{
return p2p_peer_channels_check(p2p, &p2p->channels, dev,
channel_list, channel_list_len);
}
u16 p2p_wps_method_pw_id(enum p2p_wps_method wps_method)
{
switch (wps_method) {
case WPS_PIN_DISPLAY:
return DEV_PW_REGISTRAR_SPECIFIED;
case WPS_PIN_KEYPAD:
return DEV_PW_USER_SPECIFIED;
case WPS_PBC:
return DEV_PW_PUSHBUTTON;
default:
return DEV_PW_DEFAULT;
}
}
static const char * p2p_wps_method_str(enum p2p_wps_method wps_method)
{
switch (wps_method) {
case WPS_PIN_DISPLAY:
return "Display";
case WPS_PIN_KEYPAD:
return "Keypad";
case WPS_PBC:
return "PBC";
default:
return "??";
}
}
static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
struct p2p_device *peer)
{
struct wpabuf *buf;
u8 *len;
u8 group_capab;
size_t extra = 0;
#ifdef CONFIG_WIFI_DISPLAY
if (p2p->wfd_ie_go_neg)
extra = wpabuf_len(p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */
buf = wpabuf_alloc(1000 + extra);
if (buf == NULL)
return NULL;
peer->dialog_token++;
if (peer->dialog_token == 0)
peer->dialog_token = 1;
p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_REQ, peer->dialog_token);
len = p2p_buf_add_ie_hdr(buf);
group_capab = 0;
if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
group_capab |= P2P_GROUP_CAPAB_PERSISTENT_RECONN;
}
if (p2p->cross_connect)
group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
if (p2p->cfg->p2p_intra_bss)
group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
p2p_buf_add_capability(buf, p2p->dev_capab &
~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
group_capab);
p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) |
p2p->next_tie_breaker);
p2p->next_tie_breaker = !p2p->next_tie_breaker;
p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout);
p2p_buf_add_listen_channel(buf, p2p->cfg->country, p2p->cfg->reg_class,
p2p->cfg->channel);
if (p2p->ext_listen_interval)
p2p_buf_add_ext_listen_timing(buf, p2p->ext_listen_period,
p2p->ext_listen_interval);
p2p_buf_add_intended_addr(buf, p2p->intended_addr);
p2p_buf_add_channel_list(buf, p2p->cfg->country, &p2p->channels);
p2p_buf_add_device_info(buf, p2p, peer);
p2p_buf_add_operating_channel(buf, p2p->cfg->country,
p2p->op_reg_class, p2p->op_channel);
p2p_buf_update_ie_hdr(buf, len);
/* WPS IE with Device Password ID attribute */
p2p_build_wps_ie(p2p, buf, p2p_wps_method_pw_id(peer->wps_method), 0);
#ifdef CONFIG_WIFI_DISPLAY
if (p2p->wfd_ie_go_neg)
wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */
return buf;
}
int p2p_connect_send(struct p2p_data *p2p, struct p2p_device *dev)
{
struct wpabuf *req;
int freq;
if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) {
u16 config_method;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Use PD-before-GO-Neg workaround for " MACSTR,
MAC2STR(dev->info.p2p_device_addr));
if (dev->wps_method == WPS_PIN_DISPLAY)
config_method = WPS_CONFIG_KEYPAD;
else if (dev->wps_method == WPS_PIN_KEYPAD)
config_method = WPS_CONFIG_DISPLAY;
else if (dev->wps_method == WPS_PBC)
config_method = WPS_CONFIG_PUSHBUTTON;
else
return -1;
return p2p_prov_disc_req(p2p, dev->info.p2p_device_addr,
config_method, 0, 0);
}
freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
if (freq <= 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Listen/Operating frequency known for the "
"peer " MACSTR " to send GO Negotiation Request",
MAC2STR(dev->info.p2p_device_addr));
return -1;
}
req = p2p_build_go_neg_req(p2p, dev);
if (req == NULL)
return -1;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Sending GO Negotiation Request");
p2p_set_state(p2p, P2P_CONNECT);
p2p->pending_action_state = P2P_PENDING_GO_NEG_REQUEST;
p2p->go_neg_peer = dev;
dev->flags |= P2P_DEV_WAIT_GO_NEG_RESPONSE;
dev->connect_reqs++;
if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
p2p->cfg->dev_addr, dev->info.p2p_device_addr,
wpabuf_head(req), wpabuf_len(req), 200) < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Failed to send Action frame");
/* Use P2P find to recover and retry */
p2p_set_timeout(p2p, 0, 0);
} else
dev->go_neg_req_sent++;
wpabuf_free(req);
return 0;
}
static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
struct p2p_device *peer,
u8 dialog_token, u8 status,
u8 tie_breaker)
{
struct wpabuf *buf;
u8 *len;
u8 group_capab;
size_t extra = 0;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Building GO Negotiation Response");
#ifdef CONFIG_WIFI_DISPLAY
if (p2p->wfd_ie_go_neg)
extra = wpabuf_len(p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */
buf = wpabuf_alloc(1000 + extra);
if (buf == NULL)
return NULL;
p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_RESP, dialog_token);
len = p2p_buf_add_ie_hdr(buf);
p2p_buf_add_status(buf, status);
group_capab = 0;
if (peer && peer->go_state == LOCAL_GO) {
if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
group_capab |=
P2P_GROUP_CAPAB_PERSISTENT_RECONN;
}
if (p2p->cross_connect)
group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
if (p2p->cfg->p2p_intra_bss)
group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
}
p2p_buf_add_capability(buf, p2p->dev_capab &
~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
group_capab);
p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | tie_breaker);
p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout);
if (peer && peer->go_state == REMOTE_GO) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Omit Operating "
"Channel attribute");
} else {
p2p_buf_add_operating_channel(buf, p2p->cfg->country,
p2p->op_reg_class,
p2p->op_channel);
}
p2p_buf_add_intended_addr(buf, p2p->intended_addr);
if (status || peer == NULL) {
p2p_buf_add_channel_list(buf, p2p->cfg->country,
&p2p->channels);
} else if (peer->go_state == REMOTE_GO) {
p2p_buf_add_channel_list(buf, p2p->cfg->country,
&p2p->channels);
} else {
struct p2p_channels res;
p2p_channels_intersect(&p2p->channels, &peer->channels,
&res);
p2p_buf_add_channel_list(buf, p2p->cfg->country, &res);
}
p2p_buf_add_device_info(buf, p2p, peer);
if (peer && peer->go_state == LOCAL_GO) {
p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid,
p2p->ssid_len);
}
p2p_buf_update_ie_hdr(buf, len);
/* WPS IE with Device Password ID attribute */
p2p_build_wps_ie(p2p, buf,
p2p_wps_method_pw_id(peer ? peer->wps_method :
WPS_NOT_READY), 0);
#ifdef CONFIG_WIFI_DISPLAY
if (p2p->wfd_ie_go_neg)
wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */
return buf;
}
void p2p_reselect_channel(struct p2p_data *p2p,
struct p2p_channels *intersection)
{
struct p2p_reg_class *cl;
int freq;
u8 op_reg_class, op_channel;
unsigned int i;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Selected operating "
"channel (reg_class %u channel %u) not acceptable to the "
"peer", p2p->op_reg_class, p2p->op_channel);
/* First, try to pick the best channel from another band */
freq = p2p_channel_to_freq(p2p->cfg->country, p2p->op_reg_class,
p2p->op_channel);
if (freq >= 2400 && freq < 2500 && p2p->best_freq_5 > 0 &&
p2p_freq_to_channel(p2p->cfg->country, p2p->best_freq_5,
&op_reg_class, &op_channel) == 0 &&
p2p_channels_includes(intersection, op_reg_class, op_channel)) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Pick best 5 GHz "
"channel (reg_class %u channel %u) from intersection",
op_reg_class, op_channel);
p2p->op_reg_class = op_reg_class;
p2p->op_channel = op_channel;
return;
}
if (freq >= 4900 && freq < 6000 && p2p->best_freq_24 > 0 &&
p2p_freq_to_channel(p2p->cfg->country, p2p->best_freq_24,
&op_reg_class, &op_channel) == 0 &&
p2p_channels_includes(intersection, op_reg_class, op_channel)) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Pick best 2.4 GHz "
"channel (reg_class %u channel %u) from intersection",
op_reg_class, op_channel);
p2p->op_reg_class = op_reg_class;
p2p->op_channel = op_channel;
return;
}
/* Select channel with highest preference if the peer supports it */
for (i = 0; p2p->cfg->pref_chan && i < p2p->cfg->num_pref_chan; i++) {
if (p2p_channels_includes(intersection,
p2p->cfg->pref_chan[i].op_class,
p2p->cfg->pref_chan[i].chan)) {
p2p->op_reg_class = p2p->cfg->pref_chan[i].op_class;
p2p->op_channel = p2p->cfg->pref_chan[i].chan;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Pick "
"highest preferred chnnel (op_class %u "
"channel %u) from intersection",
p2p->op_reg_class, p2p->op_channel);
return;
}
}
/*
* Fall back to whatever is included in the channel intersection since
* no better options seems to be available.
*/
cl = &intersection->reg_class[0];
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Pick another channel "
"(reg_class %u channel %u) from intersection",
cl->reg_class, cl->channel[0]);
p2p->op_reg_class = cl->reg_class;
p2p->op_channel = cl->channel[0];
}
void p2p_process_go_neg_req(struct p2p_data *p2p, const u8 *sa,
const u8 *data, size_t len, int rx_freq)
{
struct p2p_device *dev = NULL;
struct wpabuf *resp;
struct p2p_message msg;
u8 status = P2P_SC_FAIL_INVALID_PARAMS;
int tie_breaker = 0;
int freq;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Received GO Negotiation Request from " MACSTR
"(freq=%d)", MAC2STR(sa), rx_freq);
if (p2p_parse(data, len, &msg))
return;
if (!msg.capability) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory Capability attribute missing from GO "
"Negotiation Request");
#ifdef CONFIG_P2P_STRICT
goto fail;
#endif /* CONFIG_P2P_STRICT */
}
if (msg.go_intent)
tie_breaker = *msg.go_intent & 0x01;
else {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory GO Intent attribute missing from GO "
"Negotiation Request");
#ifdef CONFIG_P2P_STRICT
goto fail;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.config_timeout) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory Configuration Timeout attribute "
"missing from GO Negotiation Request");
#ifdef CONFIG_P2P_STRICT
goto fail;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.listen_channel) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Listen Channel attribute received");
goto fail;
}
if (!msg.operating_channel) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Operating Channel attribute received");
goto fail;
}
if (!msg.channel_list) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Channel List attribute received");
goto fail;
}
if (!msg.intended_addr) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Intended P2P Interface Address attribute "
"received");
goto fail;
}
if (!msg.p2p_device_info) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No P2P Device Info attribute received");
goto fail;
}
if (os_memcmp(msg.p2p_device_addr, sa, ETH_ALEN) != 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unexpected GO Negotiation Request SA=" MACSTR
" != dev_addr=" MACSTR,
MAC2STR(sa), MAC2STR(msg.p2p_device_addr));
goto fail;
}
dev = p2p_get_device(p2p, sa);
if (msg.status && *msg.status) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unexpected Status attribute (%d) in GO "
"Negotiation Request", *msg.status);
goto fail;
}
if (dev == NULL)
dev = p2p_add_dev_from_go_neg_req(p2p, sa, &msg);
else if (dev->flags & P2P_DEV_PROBE_REQ_ONLY)
p2p_add_dev_info(p2p, sa, dev, &msg);
if (dev && dev->flags & P2P_DEV_USER_REJECTED) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: User has rejected this peer");
status = P2P_SC_FAIL_REJECTED_BY_USER;
} else if (dev == NULL || dev->wps_method == WPS_NOT_READY) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Not ready for GO negotiation with " MACSTR,
MAC2STR(sa));
status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE;
if (dev)
dev->flags |= P2P_DEV_PEER_WAITING_RESPONSE;
p2p->cfg->go_neg_req_rx(p2p->cfg->cb_ctx, sa,
msg.dev_password_id);
} else if (p2p->go_neg_peer && p2p->go_neg_peer != dev) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Already in Group Formation with another peer");
status = P2P_SC_FAIL_UNABLE_TO_ACCOMMODATE;
} else {
int go;
if (!p2p->go_neg_peer) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Starting "
"GO Negotiation with previously authorized "
"peer");
if (!(dev->flags & P2P_DEV_FORCE_FREQ)) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Use default channel settings");
p2p->op_reg_class = p2p->cfg->op_reg_class;
p2p->op_channel = p2p->cfg->op_channel;
os_memcpy(&p2p->channels, &p2p->cfg->channels,
sizeof(struct p2p_channels));
} else {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Use previously configured "
"forced channel settings");
}
}
dev->flags &= ~P2P_DEV_NOT_YET_READY;
if (!msg.go_intent) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No GO Intent attribute received");
goto fail;
}
if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Invalid GO Intent value (%u) received",
*msg.go_intent >> 1);
goto fail;
}
if (dev->go_neg_req_sent &&
os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) > 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Do not reply since peer has higher "
"address and GO Neg Request already sent");
p2p_parse_free(&msg);
return;
}
go = p2p_go_det(p2p->go_intent, *msg.go_intent);
if (go < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Incompatible GO Intent");
status = P2P_SC_FAIL_BOTH_GO_INTENT_15;
goto fail;
}
if (p2p_peer_channels(p2p, dev, msg.channel_list,
msg.channel_list_len) < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No common channels found");
status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
goto fail;
}
switch (msg.dev_password_id) {
case DEV_PW_REGISTRAR_SPECIFIED:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: PIN from peer Display");
if (dev->wps_method != WPS_PIN_KEYPAD) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: We have wps_method=%s -> "
"incompatible",
p2p_wps_method_str(dev->wps_method));
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
break;
case DEV_PW_USER_SPECIFIED:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Peer entered PIN on Keypad");
if (dev->wps_method != WPS_PIN_DISPLAY) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: We have wps_method=%s -> "
"incompatible",
p2p_wps_method_str(dev->wps_method));
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
break;
case DEV_PW_PUSHBUTTON:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Peer using pushbutton");
if (dev->wps_method != WPS_PBC) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: We have wps_method=%s -> "
"incompatible",
p2p_wps_method_str(dev->wps_method));
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
break;
default:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unsupported Device Password ID %d",
msg.dev_password_id);
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
if (go) {
struct p2p_channels intersection;
size_t i;
p2p_channels_intersect(&p2p->channels, &dev->channels,
&intersection);
if (intersection.reg_classes == 0 ||
intersection.reg_class[0].channels == 0) {
status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No common channels found");
goto fail;
}
for (i = 0; i < intersection.reg_classes; i++) {
struct p2p_reg_class *c;
c = &intersection.reg_class[i];
wpa_printf(MSG_DEBUG, "P2P: reg_class %u",
c->reg_class);
wpa_hexdump(MSG_DEBUG, "P2P: channels",
c->channel, c->channels);
}
if (!p2p_channels_includes(&intersection,
p2p->op_reg_class,
p2p->op_channel))
p2p_reselect_channel(p2p, &intersection);
if (!p2p->ssid_set) {
p2p_build_ssid(p2p, p2p->ssid, &p2p->ssid_len);
p2p->ssid_set = 1;
}
}
dev->go_state = go ? LOCAL_GO : REMOTE_GO;
dev->oper_freq = p2p_channel_to_freq((const char *)
msg.operating_channel,
msg.operating_channel[3],
msg.operating_channel[4]);
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer operating "
"channel preference: %d MHz", dev->oper_freq);
if (msg.config_timeout) {
dev->go_timeout = msg.config_timeout[0];
dev->client_timeout = msg.config_timeout[1];
}
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: GO Negotiation with " MACSTR, MAC2STR(sa));
if (p2p->state != P2P_IDLE)
p2p_stop_find_for_freq(p2p, rx_freq);
p2p_set_state(p2p, P2P_GO_NEG);
p2p_clear_timeout(p2p);
dev->dialog_token = msg.dialog_token;
os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN);
p2p->go_neg_peer = dev;
status = P2P_SC_SUCCESS;
}
fail:
if (dev)
dev->status = status;
resp = p2p_build_go_neg_resp(p2p, dev, msg.dialog_token, status,
!tie_breaker);
p2p_parse_free(&msg);
if (resp == NULL)
return;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Sending GO Negotiation Response");
if (rx_freq > 0)
freq = rx_freq;
else
freq = p2p_channel_to_freq(p2p->cfg->country,
p2p->cfg->reg_class,
p2p->cfg->channel);
if (freq < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unknown regulatory class/channel");
wpabuf_free(resp);
return;
}
if (status == P2P_SC_SUCCESS) {
p2p->pending_action_state = P2P_PENDING_GO_NEG_RESPONSE;
dev->flags |= P2P_DEV_WAIT_GO_NEG_CONFIRM;
if (os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) < 0) {
/*
* Peer has smaller address, so the GO Negotiation
* Response from us is expected to complete
* negotiation. Ignore a GO Negotiation Response from
* the peer if it happens to be received after this
* point due to a race condition in GO Negotiation
* Request transmission and processing.
*/
dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE;
}
} else
p2p->pending_action_state =
P2P_PENDING_GO_NEG_RESPONSE_FAILURE;
if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr,
p2p->cfg->dev_addr,
wpabuf_head(resp), wpabuf_len(resp), 250) < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Failed to send Action frame");
}
wpabuf_free(resp);
}
static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
struct p2p_device *peer,
u8 dialog_token, u8 status,
const u8 *resp_chan, int go)
{
struct wpabuf *buf;
u8 *len;
struct p2p_channels res;
u8 group_capab;
size_t extra = 0;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Building GO Negotiation Confirm");
#ifdef CONFIG_WIFI_DISPLAY
if (p2p->wfd_ie_go_neg)
extra = wpabuf_len(p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */
buf = wpabuf_alloc(1000 + extra);
if (buf == NULL)
return NULL;
p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_CONF, dialog_token);
len = p2p_buf_add_ie_hdr(buf);
p2p_buf_add_status(buf, status);
group_capab = 0;
if (peer->go_state == LOCAL_GO) {
if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
group_capab |=
P2P_GROUP_CAPAB_PERSISTENT_RECONN;
}
if (p2p->cross_connect)
group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
if (p2p->cfg->p2p_intra_bss)
group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
}
p2p_buf_add_capability(buf, p2p->dev_capab &
~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
group_capab);
if (go || resp_chan == NULL)
p2p_buf_add_operating_channel(buf, p2p->cfg->country,
p2p->op_reg_class,
p2p->op_channel);
else
p2p_buf_add_operating_channel(buf, (const char *) resp_chan,
resp_chan[3], resp_chan[4]);
p2p_channels_intersect(&p2p->channels, &peer->channels, &res);
p2p_buf_add_channel_list(buf, p2p->cfg->country, &res);
if (go) {
p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid,
p2p->ssid_len);
}
p2p_buf_update_ie_hdr(buf, len);
#ifdef CONFIG_WIFI_DISPLAY
if (p2p->wfd_ie_go_neg)
wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
#endif /* CONFIG_WIFI_DISPLAY */
return buf;
}
void p2p_process_go_neg_resp(struct p2p_data *p2p, const u8 *sa,
const u8 *data, size_t len, int rx_freq)
{
struct p2p_device *dev;
struct wpabuf *conf;
int go = -1;
struct p2p_message msg;
u8 status = P2P_SC_SUCCESS;
int freq;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Received GO Negotiation Response from " MACSTR
" (freq=%d)", MAC2STR(sa), rx_freq);
dev = p2p_get_device(p2p, sa);
if (dev == NULL || dev->wps_method == WPS_NOT_READY ||
dev != p2p->go_neg_peer) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Not ready for GO negotiation with " MACSTR,
MAC2STR(sa));
return;
}
if (p2p_parse(data, len, &msg))
return;
if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_RESPONSE)) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Was not expecting GO Negotiation Response - "
"ignore");
p2p_parse_free(&msg);
return;
}
dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE;
if (msg.dialog_token != dev->dialog_token) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unexpected Dialog Token %u (expected %u)",
msg.dialog_token, dev->dialog_token);
p2p_parse_free(&msg);
return;
}
if (!msg.status) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Status attribute received");
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
}
if (*msg.status) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: GO Negotiation rejected: status %d",
*msg.status);
dev->go_neg_req_sent = 0;
if (*msg.status == P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Wait for the peer to become ready for "
"GO Negotiation");
dev->flags |= P2P_DEV_NOT_YET_READY;
dev->wait_count = 0;
p2p_set_state(p2p, P2P_WAIT_PEER_IDLE);
p2p_set_timeout(p2p, 0, 0);
} else {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Stop GO Negotiation attempt");
p2p_go_neg_failed(p2p, dev, *msg.status);
}
p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
p2p_parse_free(&msg);
return;
}
if (!msg.capability) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory Capability attribute missing from GO "
"Negotiation Response");
#ifdef CONFIG_P2P_STRICT
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.p2p_device_info) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory P2P Device Info attribute missing "
"from GO Negotiation Response");
#ifdef CONFIG_P2P_STRICT
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.intended_addr) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Intended P2P Interface Address attribute "
"received");
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
}
if (!msg.go_intent) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No GO Intent attribute received");
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
}
if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Invalid GO Intent value (%u) received",
*msg.go_intent >> 1);
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
}
go = p2p_go_det(p2p->go_intent, *msg.go_intent);
if (go < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Incompatible GO Intent");
status = P2P_SC_FAIL_INCOMPATIBLE_PARAMS;
goto fail;
}
if (!go && msg.group_id) {
/* Store SSID for Provisioning step */
p2p->ssid_len = msg.group_id_len - ETH_ALEN;
os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len);
} else if (!go) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory P2P Group ID attribute missing from "
"GO Negotiation Response");
p2p->ssid_len = 0;
#ifdef CONFIG_P2P_STRICT
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.config_timeout) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory Configuration Timeout attribute "
"missing from GO Negotiation Response");
#ifdef CONFIG_P2P_STRICT
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
#endif /* CONFIG_P2P_STRICT */
} else {
dev->go_timeout = msg.config_timeout[0];
dev->client_timeout = msg.config_timeout[1];
}
if (!msg.operating_channel && !go) {
/*
* Note: P2P Client may omit Operating Channel attribute to
* indicate it does not have a preference.
*/
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Operating Channel attribute received");
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
}
if (!msg.channel_list) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Channel List attribute received");
status = P2P_SC_FAIL_INVALID_PARAMS;
goto fail;
}
if (p2p_peer_channels(p2p, dev, msg.channel_list,
msg.channel_list_len) < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No common channels found");
status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
goto fail;
}
if (msg.operating_channel) {
dev->oper_freq = p2p_channel_to_freq((const char *)
msg.operating_channel,
msg.operating_channel[3],
msg.operating_channel[4]);
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer operating "
"channel preference: %d MHz", dev->oper_freq);
} else
dev->oper_freq = 0;
switch (msg.dev_password_id) {
case DEV_PW_REGISTRAR_SPECIFIED:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: PIN from peer Display");
if (dev->wps_method != WPS_PIN_KEYPAD) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: We have wps_method=%s -> "
"incompatible",
p2p_wps_method_str(dev->wps_method));
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
break;
case DEV_PW_USER_SPECIFIED:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Peer entered PIN on Keypad");
if (dev->wps_method != WPS_PIN_DISPLAY) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: We have wps_method=%s -> "
"incompatible",
p2p_wps_method_str(dev->wps_method));
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
break;
case DEV_PW_PUSHBUTTON:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Peer using pushbutton");
if (dev->wps_method != WPS_PBC) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: We have wps_method=%s -> "
"incompatible",
p2p_wps_method_str(dev->wps_method));
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
break;
default:
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unsupported Device Password ID %d",
msg.dev_password_id);
status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
goto fail;
}
if (go) {
struct p2p_channels intersection;
size_t i;
p2p_channels_intersect(&p2p->channels, &dev->channels,
&intersection);
if (intersection.reg_classes == 0 ||
intersection.reg_class[0].channels == 0) {
status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No common channels found");
goto fail;
}
for (i = 0; i < intersection.reg_classes; i++) {
struct p2p_reg_class *c;
c = &intersection.reg_class[i];
wpa_printf(MSG_DEBUG, "P2P: reg_class %u",
c->reg_class);
wpa_hexdump(MSG_DEBUG, "P2P: channels",
c->channel, c->channels);
}
if (!p2p_channels_includes(&intersection, p2p->op_reg_class,
p2p->op_channel))
p2p_reselect_channel(p2p, &intersection);
if (!p2p->ssid_set) {
p2p_build_ssid(p2p, p2p->ssid, &p2p->ssid_len);
p2p->ssid_set = 1;
}
}
p2p_set_state(p2p, P2P_GO_NEG);
p2p_clear_timeout(p2p);
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: GO Negotiation with " MACSTR, MAC2STR(sa));
os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN);
fail:
conf = p2p_build_go_neg_conf(p2p, dev, msg.dialog_token, status,
msg.operating_channel, go);
p2p_parse_free(&msg);
if (conf == NULL)
return;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Sending GO Negotiation Confirm");
if (status == P2P_SC_SUCCESS) {
p2p->pending_action_state = P2P_PENDING_GO_NEG_CONFIRM;
dev->go_state = go ? LOCAL_GO : REMOTE_GO;
} else
p2p->pending_action_state = P2P_NO_PENDING_ACTION;
if (rx_freq > 0)
freq = rx_freq;
else
freq = dev->listen_freq;
if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, sa,
wpabuf_head(conf), wpabuf_len(conf), 0) < 0) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Failed to send Action frame");
p2p_go_neg_failed(p2p, dev, -1);
}
wpabuf_free(conf);
}
void p2p_process_go_neg_conf(struct p2p_data *p2p, const u8 *sa,
const u8 *data, size_t len)
{
struct p2p_device *dev;
struct p2p_message msg;
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Received GO Negotiation Confirm from " MACSTR,
MAC2STR(sa));
dev = p2p_get_device(p2p, sa);
if (dev == NULL || dev->wps_method == WPS_NOT_READY ||
dev != p2p->go_neg_peer) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Not ready for GO negotiation with " MACSTR,
MAC2STR(sa));
return;
}
if (p2p->pending_action_state == P2P_PENDING_GO_NEG_RESPONSE) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Stopped waiting "
"for TX status on GO Negotiation Response since we "
"already received Confirmation");
p2p->pending_action_state = P2P_NO_PENDING_ACTION;
}
if (p2p_parse(data, len, &msg))
return;
if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_CONFIRM)) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Was not expecting GO Negotiation Confirm - "
"ignore");
return;
}
dev->flags &= ~P2P_DEV_WAIT_GO_NEG_CONFIRM;
if (msg.dialog_token != dev->dialog_token) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unexpected Dialog Token %u (expected %u)",
msg.dialog_token, dev->dialog_token);
p2p_parse_free(&msg);
return;
}
if (!msg.status) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: No Status attribute received");
p2p_parse_free(&msg);
return;
}
if (*msg.status) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: GO Negotiation rejected: status %d",
*msg.status);
p2p_parse_free(&msg);
return;
}
if (dev->go_state == REMOTE_GO && msg.group_id) {
/* Store SSID for Provisioning step */
p2p->ssid_len = msg.group_id_len - ETH_ALEN;
os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len);
} else if (dev->go_state == REMOTE_GO) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory P2P Group ID attribute missing from "
"GO Negotiation Confirmation");
p2p->ssid_len = 0;
#ifdef CONFIG_P2P_STRICT
p2p_parse_free(&msg);
return;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.operating_channel) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory Operating Channel attribute missing "
"from GO Negotiation Confirmation");
#ifdef CONFIG_P2P_STRICT
p2p_parse_free(&msg);
return;
#endif /* CONFIG_P2P_STRICT */
}
if (!msg.channel_list) {
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Mandatory Operating Channel attribute missing "
"from GO Negotiation Confirmation");
#ifdef CONFIG_P2P_STRICT
p2p_parse_free(&msg);
return;
#endif /* CONFIG_P2P_STRICT */
}
p2p_parse_free(&msg);
if (dev->go_state == UNKNOWN_GO) {
/*
* This should not happen since GO negotiation has already
* been completed.
*/
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
"P2P: Unexpected GO Neg state - do not know which end "
"becomes GO");
return;
}
/*
* The peer could have missed our ctrl::ack frame for GO Negotiation
* Confirm and continue retransmitting the frame. To reduce the
* likelihood of the peer not getting successful TX status for the
* GO Negotiation Confirm frame, wait a short time here before starting
* the group so that we will remain on the current channel to
* acknowledge any possible retransmission from the peer.
*/
wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: 20 ms wait on current "
"channel before starting group");
os_sleep(0, 20000);
p2p_go_complete(p2p, dev);
}
Reference in New Issue View Git Blame Copy Permalink