hostap/wlantest/rx_tdls.c

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/*
* Received Data frame processing for TDLS packets
* Copyright (c) 2010, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "crypto/sha256.h"
#include "crypto/crypto.h"
#include "crypto/aes_wrap.h"
#include "common/ieee802_11_defs.h"
#include "common/ieee802_11_common.h"
#include "wlantest.h"
static struct wlantest_tdls * get_tdls(struct wlantest *wt, const u8 *linkid,
int create_new)
{
struct wlantest_bss *bss;
struct wlantest_sta *init, *resp;
struct wlantest_tdls *tdls;
bss = bss_find(wt, linkid);
if (bss == NULL)
return NULL;
init = sta_find(bss, linkid + ETH_ALEN);
if (init == NULL)
return NULL;
resp = sta_find(bss, linkid + 2 * ETH_ALEN);
if (resp == NULL)
return NULL;
dl_list_for_each(tdls, &bss->tdls, struct wlantest_tdls, list) {
if (tdls->init == init && tdls->resp == resp)
return tdls;
}
if (!create_new)
return NULL;
tdls = os_zalloc(sizeof(*tdls));
if (tdls == NULL)
return NULL;
tdls->init = init;
tdls->resp = resp;
dl_list_add(&bss->tdls, &tdls->list);
return tdls;
}
static int tdls_derive_tpk(struct wlantest_tdls *tdls, const u8 *bssid,
const u8 *ftie, u8 ftie_len)
{
const struct rsn_ftie *f;
u8 key_input[SHA256_MAC_LEN];
const u8 *nonce[2];
size_t len[2];
u8 data[3 * ETH_ALEN];
if (ftie == NULL || ftie_len < sizeof(struct rsn_ftie))
return 0;
f = (const struct rsn_ftie *) ftie;
wpa_hexdump(MSG_DEBUG, "TDLS ANonce", f->anonce, WPA_NONCE_LEN);
wpa_hexdump(MSG_DEBUG, "TDLS SNonce", f->snonce, WPA_NONCE_LEN);
/*
* IEEE Std 802.11z-2010 8.5.9.1:
* TPK-Key-Input = SHA-256(min(SNonce, ANonce) || max(SNonce, ANonce))
*/
len[0] = WPA_NONCE_LEN;
len[1] = WPA_NONCE_LEN;
if (os_memcmp(f->anonce, f->snonce, WPA_NONCE_LEN) < 0) {
nonce[0] = f->anonce;
nonce[1] = f->snonce;
} else {
nonce[0] = f->snonce;
nonce[1] = f->anonce;
}
sha256_vector(2, nonce, len, key_input);
wpa_hexdump_key(MSG_DEBUG, "TDLS: TPK-Key-Input",
key_input, SHA256_MAC_LEN);
/*
* TPK-Key-Data = KDF-N_KEY(TPK-Key-Input, "TDLS PMK",
* min(MAC_I, MAC_R) || max(MAC_I, MAC_R) || BSSID || N_KEY)
* TODO: is N_KEY really included in KDF Context and if so, in which
* presentation format (little endian 16-bit?) is it used? It gets
* added by the KDF anyway..
*/
if (os_memcmp(tdls->init->addr, tdls->resp->addr, ETH_ALEN) < 0) {
os_memcpy(data, tdls->init->addr, ETH_ALEN);
os_memcpy(data + ETH_ALEN, tdls->resp->addr, ETH_ALEN);
} else {
os_memcpy(data, tdls->resp->addr, ETH_ALEN);
os_memcpy(data + ETH_ALEN, tdls->init->addr, ETH_ALEN);
}
os_memcpy(data + 2 * ETH_ALEN, bssid, ETH_ALEN);
wpa_hexdump(MSG_DEBUG, "TDLS: KDF Context", data, sizeof(data));
sha256_prf(key_input, SHA256_MAC_LEN, "TDLS PMK", data, sizeof(data),
(u8 *) &tdls->tpk, sizeof(tdls->tpk));
wpa_hexdump_key(MSG_DEBUG, "TDLS: TPK-KCK",
tdls->tpk.kck, sizeof(tdls->tpk.kck));
wpa_hexdump_key(MSG_DEBUG, "TDLS: TPK-TK",
tdls->tpk.tk, sizeof(tdls->tpk.tk));
return 1;
}
static int tdls_verify_mic(struct wlantest_tdls *tdls, u8 trans_seq,
struct ieee802_11_elems *elems)
{
u8 *buf, *pos;
int len;
u8 mic[16];
int ret;
const struct rsn_ftie *rx_ftie;
struct rsn_ftie *tmp_ftie;
if (elems->link_id == NULL || elems->rsn_ie == NULL ||
elems->timeout_int == NULL || elems->ftie == NULL)
return -1;
len = 2 * ETH_ALEN + 1 + 2 + 18 + 2 + elems->rsn_ie_len +
2 + elems->timeout_int_len + 2 + elems->ftie_len;
buf = os_zalloc(len);
if (buf == NULL)
return -1;
pos = buf;
/* 1) TDLS initiator STA MAC address */
os_memcpy(pos, elems->link_id + ETH_ALEN, ETH_ALEN);
pos += ETH_ALEN;
/* 2) TDLS responder STA MAC address */
os_memcpy(pos, elems->link_id + 2 * ETH_ALEN, ETH_ALEN);
pos += ETH_ALEN;
/* 3) Transaction Sequence number */
*pos++ = trans_seq;
/* 4) Link Identifier IE */
os_memcpy(pos, elems->link_id - 2, 2 + 18);
pos += 2 + 18;
/* 5) RSN IE */
os_memcpy(pos, elems->rsn_ie - 2, 2 + elems->rsn_ie_len);
pos += 2 + elems->rsn_ie_len;
/* 6) Timeout Interval IE */
os_memcpy(pos, elems->timeout_int - 2, 2 + elems->timeout_int_len);
pos += 2 + elems->timeout_int_len;
/* 7) FTIE, with the MIC field of the FTIE set to 0 */
os_memcpy(pos, elems->ftie - 2, 2 + elems->ftie_len);
pos += 2;
tmp_ftie = (struct rsn_ftie *) pos;
os_memset(tmp_ftie->mic, 0, 16);
pos += elems->ftie_len;
wpa_hexdump(MSG_DEBUG, "TDLS: Data for FTIE MIC", buf, pos - buf);
wpa_hexdump_key(MSG_DEBUG, "TDLS: KCK", tdls->tpk.kck, 16);
ret = omac1_aes_128(tdls->tpk.kck, buf, pos - buf, mic);
os_free(buf);
if (ret)
return -1;
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE MIC", mic, 16);
rx_ftie = (const struct rsn_ftie *) elems->ftie;
if (os_memcmp(mic, rx_ftie->mic, 16) == 0) {
wpa_printf(MSG_DEBUG, "TDLS: Valid MIC");
return 0;
}
wpa_printf(MSG_DEBUG, "TDLS: Invalid MIC");
return -1;
}
static void rx_data_tdls_setup_request(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, const u8 *dst,
const u8 *src,
const u8 *data, size_t len)
{
struct ieee802_11_elems elems;
struct wlantest_tdls *tdls;
if (len < 3)
return;
wpa_printf(MSG_DEBUG, "TDLS Setup Request " MACSTR " -> "
MACSTR, MAC2STR(src), MAC2STR(dst));
if (ieee802_11_parse_elems(data + 3, len - 3, &elems, 1) ==
ParseFailed || elems.link_id == NULL)
return;
wpa_printf(MSG_DEBUG, "TDLS Link Identifier: BSSID " MACSTR
" initiator STA " MACSTR " responder STA " MACSTR,
MAC2STR(elems.link_id), MAC2STR(elems.link_id + ETH_ALEN),
MAC2STR(elems.link_id + 2 * ETH_ALEN));
tdls = get_tdls(wt, elems.link_id, 1);
if (tdls)
tdls->counters[WLANTEST_TDLS_COUNTER_SETUP_REQ]++;
}
static void rx_data_tdls_setup_response(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, const u8 *dst,
const u8 *src,
const u8 *data, size_t len)
{
u16 status;
struct ieee802_11_elems elems;
struct wlantest_tdls *tdls;
if (len < 5)
return;
status = WPA_GET_LE16(data);
wpa_printf(MSG_DEBUG, "TDLS Setup Response " MACSTR " -> "
MACSTR " (status %d)",
MAC2STR(src), MAC2STR(dst), status);
if (status != WLAN_STATUS_SUCCESS)
return;
if (ieee802_11_parse_elems(data + 5, len - 5, &elems, 1) ==
ParseFailed || elems.link_id == NULL)
return;
wpa_printf(MSG_DEBUG, "TDLS Link Identifier: BSSID " MACSTR
" initiator STA " MACSTR " responder STA " MACSTR,
MAC2STR(elems.link_id), MAC2STR(elems.link_id + ETH_ALEN),
MAC2STR(elems.link_id + 2 * ETH_ALEN));
tdls = get_tdls(wt, elems.link_id, 1);
if (!tdls)
return;
if (status)
tdls->counters[WLANTEST_TDLS_COUNTER_SETUP_RESP_FAIL]++;
else
tdls->counters[WLANTEST_TDLS_COUNTER_SETUP_RESP_OK]++;
if (tdls_derive_tpk(tdls, bssid, elems.ftie, elems.ftie_len) < 1)
return;
if (tdls_verify_mic(tdls, 2, &elems) == 0) {
tdls->dialog_token = data[2];
wpa_printf(MSG_DEBUG, "TDLS: Dialog Token for the link: %u",
tdls->dialog_token);
}
}
static void rx_data_tdls_setup_confirm(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, const u8 *dst,
const u8 *src,
const u8 *data, size_t len)
{
u16 status;
struct ieee802_11_elems elems;
struct wlantest_tdls *tdls;
u8 link_id[3 * ETH_ALEN];
if (len < 3)
return;
status = WPA_GET_LE16(data);
wpa_printf(MSG_DEBUG, "TDLS Setup Confirm " MACSTR " -> "
MACSTR " (status %d)",
MAC2STR(src), MAC2STR(dst), status);
if (ieee802_11_parse_elems(data + 3, len - 3, &elems, 1) ==
ParseFailed || elems.link_id == NULL)
return;
wpa_printf(MSG_DEBUG, "TDLS Link Identifier: BSSID " MACSTR
" initiator STA " MACSTR " responder STA " MACSTR,
MAC2STR(elems.link_id), MAC2STR(elems.link_id + ETH_ALEN),
MAC2STR(elems.link_id + 2 * ETH_ALEN));
tdls = get_tdls(wt, elems.link_id, 1);
if (tdls == NULL)
return;
if (status)
tdls->counters[WLANTEST_TDLS_COUNTER_SETUP_CONF_FAIL]++;
else
tdls->counters[WLANTEST_TDLS_COUNTER_SETUP_CONF_OK]++;
if (status != WLAN_STATUS_SUCCESS)
return;
tdls->link_up = 1;
if (tdls_derive_tpk(tdls, bssid, elems.ftie, elems.ftie_len) < 1) {
if (elems.ftie == NULL)
goto remove_reverse;
return;
}
if (tdls_verify_mic(tdls, 3, &elems) == 0) {
tdls->dialog_token = data[2];
wpa_printf(MSG_DEBUG, "TDLS: Dialog Token for the link: %u",
tdls->dialog_token);
}
remove_reverse:
/*
* The TDLS link itself is bidirectional, but there is explicit
* initiator/responder roles. Remove the other direction of the link
* (if it exists) to make sure that the link counters are stored for
* the current TDLS entery.
*/
os_memcpy(link_id, elems.link_id, ETH_ALEN);
os_memcpy(link_id + ETH_ALEN, elems.link_id + 2 * ETH_ALEN, ETH_ALEN);
os_memcpy(link_id + 2 * ETH_ALEN, elems.link_id + ETH_ALEN, ETH_ALEN);
tdls = get_tdls(wt, link_id, 0);
if (tdls) {
wpa_printf(MSG_DEBUG, "TDLS: Remove reverse link entry");
tdls_deinit(tdls);
}
}
static int tdls_verify_mic_teardown(struct wlantest_tdls *tdls, u8 trans_seq,
const u8 *reason_code,
struct ieee802_11_elems *elems)
{
u8 *buf, *pos;
int len;
u8 mic[16];
int ret;
const struct rsn_ftie *rx_ftie;
struct rsn_ftie *tmp_ftie;
if (elems->link_id == NULL || elems->ftie == NULL)
return -1;
len = 2 + 18 + 2 + 1 + 1 + 2 + elems->ftie_len;
buf = os_zalloc(len);
if (buf == NULL)
return -1;
pos = buf;
/* 1) Link Identifier IE */
os_memcpy(pos, elems->link_id - 2, 2 + 18);
pos += 2 + 18;
/* 2) Reason Code */
os_memcpy(pos, reason_code, 2);
pos += 2;
/* 3) Dialog token */
*pos++ = tdls->dialog_token;
/* 4) Transaction Sequence number */
*pos++ = trans_seq;
/* 5) FTIE, with the MIC field of the FTIE set to 0 */
os_memcpy(pos, elems->ftie - 2, 2 + elems->ftie_len);
pos += 2;
tmp_ftie = (struct rsn_ftie *) pos;
os_memset(tmp_ftie->mic, 0, 16);
pos += elems->ftie_len;
wpa_hexdump(MSG_DEBUG, "TDLS: Data for FTIE MIC", buf, pos - buf);
wpa_hexdump_key(MSG_DEBUG, "TDLS: KCK", tdls->tpk.kck, 16);
ret = omac1_aes_128(tdls->tpk.kck, buf, pos - buf, mic);
os_free(buf);
if (ret)
return -1;
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE MIC", mic, 16);
rx_ftie = (const struct rsn_ftie *) elems->ftie;
if (os_memcmp(mic, rx_ftie->mic, 16) == 0) {
wpa_printf(MSG_DEBUG, "TDLS: Valid MIC");
return 0;
}
wpa_printf(MSG_DEBUG, "TDLS: Invalid MIC");
return -1;
}
static void rx_data_tdls_teardown(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, const u8 *dst,
const u8 *src,
const u8 *data, size_t len)
{
u16 reason;
struct ieee802_11_elems elems;
struct wlantest_tdls *tdls;
if (len < 2)
return;
reason = WPA_GET_LE16(data);
wpa_printf(MSG_DEBUG, "TDLS Teardown " MACSTR " -> "
MACSTR " (reason %d)",
MAC2STR(src), MAC2STR(dst), reason);
if (ieee802_11_parse_elems(data + 2, len - 2, &elems, 1) ==
ParseFailed || elems.link_id == NULL)
return;
wpa_printf(MSG_DEBUG, "TDLS Link Identifier: BSSID " MACSTR
" initiator STA " MACSTR " responder STA " MACSTR,
MAC2STR(elems.link_id), MAC2STR(elems.link_id + ETH_ALEN),
MAC2STR(elems.link_id + 2 * ETH_ALEN));
tdls = get_tdls(wt, elems.link_id, 1);
if (tdls) {
tdls->link_up = 0;
tdls_verify_mic_teardown(tdls, 4, data, &elems);
}
}
static void rx_data_tdls(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, const u8 *dst, const u8 *src,
const u8 *data, size_t len)
{
/* data contains the payload of a TDLS Action frame */
if (len < 2 || data[0] != WLAN_ACTION_TDLS) {
wpa_hexdump(MSG_DEBUG, "Unrecognized encapsulated TDLS frame",
data, len);
return;
}
switch (data[1]) {
case WLAN_TDLS_SETUP_REQUEST:
rx_data_tdls_setup_request(wt, bssid, sta_addr, dst, src,
data + 2, len - 2);
break;
case WLAN_TDLS_SETUP_RESPONSE:
rx_data_tdls_setup_response(wt, bssid, sta_addr, dst, src,
data + 2, len - 2);
break;
case WLAN_TDLS_SETUP_CONFIRM:
rx_data_tdls_setup_confirm(wt, bssid, sta_addr, dst, src,
data + 2, len - 2);
break;
case WLAN_TDLS_TEARDOWN:
rx_data_tdls_teardown(wt, bssid, sta_addr, dst, src, data + 2,
len - 2);
break;
case WLAN_TDLS_DISCOVERY_REQUEST:
wpa_printf(MSG_DEBUG, "TDLS Discovery Request " MACSTR " -> "
MACSTR, MAC2STR(src), MAC2STR(dst));
break;
}
}
void rx_data_80211_encap(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, const u8 *dst, const u8 *src,
const u8 *data, size_t len)
{
wpa_hexdump(MSG_EXCESSIVE, "802.11 data encap frame", data, len);
if (len < 1)
return;
if (data[0] == 0x02)
rx_data_tdls(wt, bssid, sta_addr, dst, src, data + 1, len - 1);
}