hostap/wpa_supplicant/rrm.c
Avraham Stern 3c716fdbd7 wpa_supplicant: Refactor wpas_rrm_build_lci_report()
1. Change the return type to reflect whether building the report
   succeeded or failed.
2. Change argument type to rrm_measurement_request_element instead
   of raw packet data to ease processing the request.
3. Use already existing function to create the measurement report
   and add it to the report buffer.

Signed-off-by: Avraham Stern <avraham.stern@intel.com>
2017-01-03 15:18:29 +02:00

638 lines
17 KiB
C

/*
* wpa_supplicant - Radio Measurements
* Copyright (c) 2003-2016, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "includes.h"
#include "utils/common.h"
#include "utils/eloop.h"
#include "common/ieee802_11_common.h"
#include "wpa_supplicant_i.h"
#include "driver_i.h"
#include "bss.h"
static void wpas_rrm_neighbor_rep_timeout_handler(void *data, void *user_ctx)
{
struct rrm_data *rrm = data;
if (!rrm->notify_neighbor_rep) {
wpa_printf(MSG_ERROR,
"RRM: Unexpected neighbor report timeout");
return;
}
wpa_printf(MSG_DEBUG, "RRM: Notifying neighbor report - NONE");
rrm->notify_neighbor_rep(rrm->neighbor_rep_cb_ctx, NULL);
rrm->notify_neighbor_rep = NULL;
rrm->neighbor_rep_cb_ctx = NULL;
}
/*
* wpas_rrm_reset - Clear and reset all RRM data in wpa_supplicant
* @wpa_s: Pointer to wpa_supplicant
*/
void wpas_rrm_reset(struct wpa_supplicant *wpa_s)
{
wpa_s->rrm.rrm_used = 0;
eloop_cancel_timeout(wpas_rrm_neighbor_rep_timeout_handler, &wpa_s->rrm,
NULL);
if (wpa_s->rrm.notify_neighbor_rep)
wpas_rrm_neighbor_rep_timeout_handler(&wpa_s->rrm, NULL);
wpa_s->rrm.next_neighbor_rep_token = 1;
}
/*
* wpas_rrm_process_neighbor_rep - Handle incoming neighbor report
* @wpa_s: Pointer to wpa_supplicant
* @report: Neighbor report buffer, prefixed by a 1-byte dialog token
* @report_len: Length of neighbor report buffer
*/
void wpas_rrm_process_neighbor_rep(struct wpa_supplicant *wpa_s,
const u8 *report, size_t report_len)
{
struct wpabuf *neighbor_rep;
wpa_hexdump(MSG_DEBUG, "RRM: New Neighbor Report", report, report_len);
if (report_len < 1)
return;
if (report[0] != wpa_s->rrm.next_neighbor_rep_token - 1) {
wpa_printf(MSG_DEBUG,
"RRM: Discarding neighbor report with token %d (expected %d)",
report[0], wpa_s->rrm.next_neighbor_rep_token - 1);
return;
}
eloop_cancel_timeout(wpas_rrm_neighbor_rep_timeout_handler, &wpa_s->rrm,
NULL);
if (!wpa_s->rrm.notify_neighbor_rep) {
wpa_printf(MSG_ERROR, "RRM: Unexpected neighbor report");
return;
}
/* skipping the first byte, which is only an id (dialog token) */
neighbor_rep = wpabuf_alloc(report_len - 1);
if (neighbor_rep == NULL)
return;
wpabuf_put_data(neighbor_rep, report + 1, report_len - 1);
wpa_printf(MSG_DEBUG, "RRM: Notifying neighbor report (token = %d)",
report[0]);
wpa_s->rrm.notify_neighbor_rep(wpa_s->rrm.neighbor_rep_cb_ctx,
neighbor_rep);
wpa_s->rrm.notify_neighbor_rep = NULL;
wpa_s->rrm.neighbor_rep_cb_ctx = NULL;
}
#if defined(__CYGWIN__) || defined(CONFIG_NATIVE_WINDOWS)
/* Workaround different, undefined for Windows, error codes used here */
#define ENOTCONN -1
#define EOPNOTSUPP -1
#define ECANCELED -1
#endif
/* Measurement Request element + Location Subject + Maximum Age subelement */
#define MEASURE_REQUEST_LCI_LEN (3 + 1 + 4)
/* Measurement Request element + Location Civic Request */
#define MEASURE_REQUEST_CIVIC_LEN (3 + 5)
/**
* wpas_rrm_send_neighbor_rep_request - Request a neighbor report from our AP
* @wpa_s: Pointer to wpa_supplicant
* @ssid: if not null, this is sent in the request. Otherwise, no SSID IE
* is sent in the request.
* @lci: if set, neighbor request will include LCI request
* @civic: if set, neighbor request will include civic location request
* @cb: Callback function to be called once the requested report arrives, or
* timed out after RRM_NEIGHBOR_REPORT_TIMEOUT seconds.
* In the former case, 'neighbor_rep' is a newly allocated wpabuf, and it's
* the requester's responsibility to free it.
* In the latter case NULL will be sent in 'neighbor_rep'.
* @cb_ctx: Context value to send the callback function
* Returns: 0 in case of success, negative error code otherwise
*
* In case there is a previous request which has not been answered yet, the
* new request fails. The caller may retry after RRM_NEIGHBOR_REPORT_TIMEOUT.
* Request must contain a callback function.
*/
int wpas_rrm_send_neighbor_rep_request(struct wpa_supplicant *wpa_s,
const struct wpa_ssid_value *ssid,
int lci, int civic,
void (*cb)(void *ctx,
struct wpabuf *neighbor_rep),
void *cb_ctx)
{
struct wpabuf *buf;
const u8 *rrm_ie;
if (wpa_s->wpa_state != WPA_COMPLETED || wpa_s->current_ssid == NULL) {
wpa_printf(MSG_DEBUG, "RRM: No connection, no RRM.");
return -ENOTCONN;
}
if (!wpa_s->rrm.rrm_used) {
wpa_printf(MSG_DEBUG, "RRM: No RRM in current connection.");
return -EOPNOTSUPP;
}
rrm_ie = wpa_bss_get_ie(wpa_s->current_bss,
WLAN_EID_RRM_ENABLED_CAPABILITIES);
if (!rrm_ie || !(wpa_s->current_bss->caps & IEEE80211_CAP_RRM) ||
!(rrm_ie[2] & WLAN_RRM_CAPS_NEIGHBOR_REPORT)) {
wpa_printf(MSG_DEBUG,
"RRM: No network support for Neighbor Report.");
return -EOPNOTSUPP;
}
if (!cb) {
wpa_printf(MSG_DEBUG,
"RRM: Neighbor Report request must provide a callback.");
return -EINVAL;
}
/* Refuse if there's a live request */
if (wpa_s->rrm.notify_neighbor_rep) {
wpa_printf(MSG_DEBUG,
"RRM: Currently handling previous Neighbor Report.");
return -EBUSY;
}
/* 3 = action category + action code + dialog token */
buf = wpabuf_alloc(3 + (ssid ? 2 + ssid->ssid_len : 0) +
(lci ? 2 + MEASURE_REQUEST_LCI_LEN : 0) +
(civic ? 2 + MEASURE_REQUEST_CIVIC_LEN : 0));
if (buf == NULL) {
wpa_printf(MSG_DEBUG,
"RRM: Failed to allocate Neighbor Report Request");
return -ENOMEM;
}
wpa_printf(MSG_DEBUG, "RRM: Neighbor report request (for %s), token=%d",
(ssid ? wpa_ssid_txt(ssid->ssid, ssid->ssid_len) : ""),
wpa_s->rrm.next_neighbor_rep_token);
wpabuf_put_u8(buf, WLAN_ACTION_RADIO_MEASUREMENT);
wpabuf_put_u8(buf, WLAN_RRM_NEIGHBOR_REPORT_REQUEST);
wpabuf_put_u8(buf, wpa_s->rrm.next_neighbor_rep_token);
if (ssid) {
wpabuf_put_u8(buf, WLAN_EID_SSID);
wpabuf_put_u8(buf, ssid->ssid_len);
wpabuf_put_data(buf, ssid->ssid, ssid->ssid_len);
}
if (lci) {
/* IEEE P802.11-REVmc/D5.0 9.4.2.21 */
wpabuf_put_u8(buf, WLAN_EID_MEASURE_REQUEST);
wpabuf_put_u8(buf, MEASURE_REQUEST_LCI_LEN);
/*
* Measurement token; nonzero number that is unique among the
* Measurement Request elements in a particular frame.
*/
wpabuf_put_u8(buf, 1); /* Measurement Token */
/*
* Parallel, Enable, Request, and Report bits are 0, Duration is
* reserved.
*/
wpabuf_put_u8(buf, 0); /* Measurement Request Mode */
wpabuf_put_u8(buf, MEASURE_TYPE_LCI); /* Measurement Type */
/* IEEE P802.11-REVmc/D5.0 9.4.2.21.10 - LCI request */
/* Location Subject */
wpabuf_put_u8(buf, LOCATION_SUBJECT_REMOTE);
/* Optional Subelements */
/*
* IEEE P802.11-REVmc/D5.0 Figure 9-170
* The Maximum Age subelement is required, otherwise the AP can
* send only data that was determined after receiving the
* request. Setting it here to unlimited age.
*/
wpabuf_put_u8(buf, LCI_REQ_SUBELEM_MAX_AGE);
wpabuf_put_u8(buf, 2);
wpabuf_put_le16(buf, 0xffff);
}
if (civic) {
/* IEEE P802.11-REVmc/D5.0 9.4.2.21 */
wpabuf_put_u8(buf, WLAN_EID_MEASURE_REQUEST);
wpabuf_put_u8(buf, MEASURE_REQUEST_CIVIC_LEN);
/*
* Measurement token; nonzero number that is unique among the
* Measurement Request elements in a particular frame.
*/
wpabuf_put_u8(buf, 2); /* Measurement Token */
/*
* Parallel, Enable, Request, and Report bits are 0, Duration is
* reserved.
*/
wpabuf_put_u8(buf, 0); /* Measurement Request Mode */
/* Measurement Type */
wpabuf_put_u8(buf, MEASURE_TYPE_LOCATION_CIVIC);
/* IEEE P802.11-REVmc/D5.0 9.4.2.21.14:
* Location Civic request */
/* Location Subject */
wpabuf_put_u8(buf, LOCATION_SUBJECT_REMOTE);
wpabuf_put_u8(buf, 0); /* Civic Location Type: IETF RFC 4776 */
/* Location Service Interval Units: Seconds */
wpabuf_put_u8(buf, 0);
/* Location Service Interval: 0 - Only one report is requested
*/
wpabuf_put_le16(buf, 0);
/* No optional subelements */
}
wpa_s->rrm.next_neighbor_rep_token++;
if (wpa_drv_send_action(wpa_s, wpa_s->assoc_freq, 0, wpa_s->bssid,
wpa_s->own_addr, wpa_s->bssid,
wpabuf_head(buf), wpabuf_len(buf), 0) < 0) {
wpa_printf(MSG_DEBUG,
"RRM: Failed to send Neighbor Report Request");
wpabuf_free(buf);
return -ECANCELED;
}
wpa_s->rrm.neighbor_rep_cb_ctx = cb_ctx;
wpa_s->rrm.notify_neighbor_rep = cb;
eloop_register_timeout(RRM_NEIGHBOR_REPORT_TIMEOUT, 0,
wpas_rrm_neighbor_rep_timeout_handler,
&wpa_s->rrm, NULL);
wpabuf_free(buf);
return 0;
}
static int wpas_rrm_report_elem(struct wpabuf *buf, u8 token, u8 mode, u8 type,
const u8 *data, size_t data_len)
{
if (wpabuf_tailroom(buf) < 5 + data_len)
return -1;
wpabuf_put_u8(buf, WLAN_EID_MEASURE_REPORT);
wpabuf_put_u8(buf, 3 + data_len);
wpabuf_put_u8(buf, token);
wpabuf_put_u8(buf, mode);
wpabuf_put_u8(buf, type);
if (data_len)
wpabuf_put_data(buf, data, data_len);
return 0;
}
static int
wpas_rrm_build_lci_report(struct wpa_supplicant *wpa_s,
const struct rrm_measurement_request_element *req,
struct wpabuf **buf)
{
u8 subject;
u16 max_age = 0;
struct os_reltime t, diff;
unsigned long diff_l;
const u8 *subelem;
const u8 *request = req->variable;
size_t len = req->len - 3;
if (len < 4)
return -1;
if (!wpa_s->lci)
goto reject;
subject = *request++;
len--;
wpa_printf(MSG_DEBUG, "Measurement request location subject=%u",
subject);
if (subject != LOCATION_SUBJECT_REMOTE) {
wpa_printf(MSG_INFO,
"Not building LCI report - bad location subject");
return 0;
}
/* Subelements are formatted exactly like elements */
subelem = get_ie(request, len, LCI_REQ_SUBELEM_MAX_AGE);
if (subelem && subelem[1] == 2)
max_age = WPA_GET_LE16(subelem + 2);
if (os_get_reltime(&t))
goto reject;
os_reltime_sub(&t, &wpa_s->lci_time, &diff);
/* LCI age is calculated in 10th of a second units. */
diff_l = diff.sec * 10 + diff.usec / 100000;
if (max_age != 0xffff && max_age < diff_l)
goto reject;
if (wpabuf_resize(buf, 5 + wpabuf_len(wpa_s->lci)))
return -1;
if (wpas_rrm_report_elem(*buf, req->token,
MEASUREMENT_REPORT_MODE_ACCEPT, req->type,
wpabuf_head_u8(wpa_s->lci),
wpabuf_len(wpa_s->lci)) < 0) {
wpa_printf(MSG_DEBUG, "Failed to add LCI report element");
return -1;
}
return 0;
reject:
if (wpabuf_resize(buf, sizeof(struct rrm_measurement_report_element))) {
wpa_printf(MSG_DEBUG, "RRM: Memory allocation failed");
return -1;
}
if (wpas_rrm_report_elem(*buf, req->token,
MEASUREMENT_REPORT_MODE_REJECT_INCAPABLE,
req->type, NULL, 0) < 0) {
wpa_printf(MSG_DEBUG, "RRM: Failed to add report element");
return -1;
}
return 0;
}
static void wpas_rrm_send_msr_report_mpdu(struct wpa_supplicant *wpa_s,
const u8 *data, size_t len)
{
struct wpabuf *report = wpabuf_alloc(len + 3);
if (!report)
return;
wpabuf_put_u8(report, WLAN_ACTION_RADIO_MEASUREMENT);
wpabuf_put_u8(report, WLAN_RRM_RADIO_MEASUREMENT_REPORT);
wpabuf_put_u8(report, wpa_s->rrm.token);
wpabuf_put_data(report, data, len);
if (wpa_drv_send_action(wpa_s, wpa_s->assoc_freq, 0, wpa_s->bssid,
wpa_s->own_addr, wpa_s->bssid,
wpabuf_head(report), wpabuf_len(report), 0)) {
wpa_printf(MSG_ERROR,
"RRM: Radio measurement report failed: Sending Action frame failed");
}
wpabuf_free(report);
}
static void wpas_rrm_send_msr_report(struct wpa_supplicant *wpa_s,
struct wpabuf *buf)
{
int len = wpabuf_len(buf);
const u8 *pos = wpabuf_head_u8(buf), *next = pos;
#define MPDU_REPORT_LEN (int) (IEEE80211_MAX_MMPDU_SIZE - IEEE80211_HDRLEN - 3)
while (len) {
int send_len = (len > MPDU_REPORT_LEN) ? next - pos : len;
if (send_len == len ||
(send_len + next[1] + 2) > MPDU_REPORT_LEN) {
wpas_rrm_send_msr_report_mpdu(wpa_s, pos, send_len);
len -= send_len;
pos = next;
}
next += next[1] + 2;
}
#undef MPDU_REPORT_LEN
}
static int
wpas_rrm_handle_msr_req_element(
struct wpa_supplicant *wpa_s,
const struct rrm_measurement_request_element *req,
struct wpabuf **buf)
{
wpa_printf(MSG_DEBUG, "Measurement request type %d token %d",
req->type, req->token);
if (req->mode & MEASUREMENT_REQUEST_MODE_ENABLE) {
/* Enable bit is not supported for now */
wpa_printf(MSG_DEBUG, "RRM: Enable bit not supported, ignore");
return 0;
}
if ((req->mode & MEASUREMENT_REQUEST_MODE_PARALLEL) &&
req->type > MEASURE_TYPE_RPI_HIST) {
/* Parallel measurements are not supported for now */
wpa_printf(MSG_DEBUG,
"RRM: Parallel measurements are not supported, reject");
goto reject;
}
switch (req->type) {
case MEASURE_TYPE_LCI:
return wpas_rrm_build_lci_report(wpa_s, req, buf);
default:
wpa_printf(MSG_INFO,
"RRM: Unsupported radio measurement type %u",
req->type);
break;
}
reject:
if (wpabuf_resize(buf, sizeof(struct rrm_measurement_report_element))) {
wpa_printf(MSG_DEBUG, "RRM: Memory allocation failed");
return -1;
}
if (wpas_rrm_report_elem(*buf, req->token,
MEASUREMENT_REPORT_MODE_REJECT_INCAPABLE,
req->type, NULL, 0) < 0) {
wpa_printf(MSG_DEBUG, "RRM: Failed to add report element");
return -1;
}
return 0;
}
static struct wpabuf *
wpas_rrm_process_msr_req_elems(struct wpa_supplicant *wpa_s, const u8 *pos,
size_t len)
{
struct wpabuf *buf = NULL;
while (len) {
const struct rrm_measurement_request_element *req;
int res;
if (len < 2) {
wpa_printf(MSG_DEBUG, "RRM: Truncated element");
goto out;
}
req = (const struct rrm_measurement_request_element *) pos;
if (req->eid != WLAN_EID_MEASURE_REQUEST) {
wpa_printf(MSG_DEBUG,
"RRM: Expected Measurement Request element, but EID is %u",
req->eid);
goto out;
}
if (req->len < 3) {
wpa_printf(MSG_DEBUG, "RRM: Element length too short");
goto out;
}
if (req->len > len - 2) {
wpa_printf(MSG_DEBUG, "RRM: Element length too long");
goto out;
}
res = wpas_rrm_handle_msr_req_element(wpa_s, req, &buf);
if (res < 0)
goto out;
pos += req->len + 2;
len -= req->len + 2;
}
return buf;
out:
wpabuf_free(buf);
return NULL;
}
void wpas_rrm_handle_radio_measurement_request(struct wpa_supplicant *wpa_s,
const u8 *src,
const u8 *frame, size_t len)
{
struct wpabuf *report;
if (wpa_s->wpa_state != WPA_COMPLETED) {
wpa_printf(MSG_INFO,
"RRM: Ignoring radio measurement request: Not associated");
return;
}
if (!wpa_s->rrm.rrm_used) {
wpa_printf(MSG_INFO,
"RRM: Ignoring radio measurement request: Not RRM network");
return;
}
if (len < 3) {
wpa_printf(MSG_INFO,
"RRM: Ignoring too short radio measurement request");
return;
}
wpa_s->rrm.token = *frame;
/* Number of repetitions is not supported */
report = wpas_rrm_process_msr_req_elems(wpa_s, frame + 3, len - 3);
if (!report)
return;
wpas_rrm_send_msr_report(wpa_s, report);
wpabuf_free(report);
}
void wpas_rrm_handle_link_measurement_request(struct wpa_supplicant *wpa_s,
const u8 *src,
const u8 *frame, size_t len,
int rssi)
{
struct wpabuf *buf;
const struct rrm_link_measurement_request *req;
struct rrm_link_measurement_report report;
if (wpa_s->wpa_state != WPA_COMPLETED) {
wpa_printf(MSG_INFO,
"RRM: Ignoring link measurement request. Not associated");
return;
}
if (!wpa_s->rrm.rrm_used) {
wpa_printf(MSG_INFO,
"RRM: Ignoring link measurement request. Not RRM network");
return;
}
if (!(wpa_s->drv_rrm_flags & WPA_DRIVER_FLAGS_TX_POWER_INSERTION)) {
wpa_printf(MSG_INFO,
"RRM: Measurement report failed. TX power insertion not supported");
return;
}
req = (const struct rrm_link_measurement_request *) frame;
if (len < sizeof(*req)) {
wpa_printf(MSG_INFO,
"RRM: Link measurement report failed. Request too short");
return;
}
os_memset(&report, 0, sizeof(report));
report.tpc.eid = WLAN_EID_TPC_REPORT;
report.tpc.len = 2;
report.rsni = 255; /* 255 indicates that RSNI is not available */
report.dialog_token = req->dialog_token;
/*
* It's possible to estimate RCPI based on RSSI in dBm. This
* calculation will not reflect the correct value for high rates,
* but it's good enough for Action frames which are transmitted
* with up to 24 Mbps rates.
*/
if (!rssi)
report.rcpi = 255; /* not available */
else if (rssi < -110)
report.rcpi = 0;
else if (rssi > 0)
report.rcpi = 220;
else
report.rcpi = (rssi + 110) * 2;
/* action_category + action_code */
buf = wpabuf_alloc(2 + sizeof(report));
if (buf == NULL) {
wpa_printf(MSG_ERROR,
"RRM: Link measurement report failed. Buffer allocation failed");
return;
}
wpabuf_put_u8(buf, WLAN_ACTION_RADIO_MEASUREMENT);
wpabuf_put_u8(buf, WLAN_RRM_LINK_MEASUREMENT_REPORT);
wpabuf_put_data(buf, &report, sizeof(report));
wpa_hexdump(MSG_DEBUG, "RRM: Link measurement report:",
wpabuf_head(buf), wpabuf_len(buf));
if (wpa_drv_send_action(wpa_s, wpa_s->assoc_freq, 0, src,
wpa_s->own_addr, wpa_s->bssid,
wpabuf_head(buf), wpabuf_len(buf), 0)) {
wpa_printf(MSG_ERROR,
"RRM: Link measurement report failed. Send action failed");
}
wpabuf_free(buf);
}