hostap/src/rsn_supp/tdls.c

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/*
* wpa_supplicant - TDLS
* Copyright (c) 2010-2011, Atheros Communications
*
* 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 "utils/eloop.h"
#include "utils/os.h"
#include "common/ieee802_11_defs.h"
#include "crypto/sha256.h"
#include "crypto/crypto.h"
#include "crypto/aes_wrap.h"
#include "rsn_supp/wpa.h"
#include "rsn_supp/wpa_ie.h"
#include "rsn_supp/wpa_i.h" /* for set key */
#include "drivers/driver.h"
#include "l2_packet/l2_packet.h"
#ifdef CONFIG_TDLS_TESTING
#define TDLS_TESTING_LONG_FRAME BIT(0)
#define TDLS_TESTING_ALT_RSN_IE BIT(1)
#define TDLS_TESTING_DIFF_BSSID BIT(2)
#define TDLS_TESTING_SHORT_LIFETIME BIT(3)
#define TDLS_TESTING_WRONG_LIFETIME_RESP BIT(4)
#define TDLS_TESTING_WRONG_LIFETIME_CONF BIT(5)
unsigned int tdls_testing = 0;
#endif /* CONFIG_TDLS_TESTING */
#define TPK_LIFETIME 43200 /* 12 hours */
#define SMK_RETRY_COUNT 3
#define SMK_TIMEOUT 5000 /* in milliseconds */
#define TDLS_MIC_LEN 16
#define TDLS_TIMEOUT_LEN 4
struct wpa_tdls_ftie {
u8 ie_type; /* FTIE */
u8 ie_len;
u8 mic_ctrl[2];
u8 mic[TDLS_MIC_LEN];
u8 Anonce[WPA_NONCE_LEN]; /* Peer Nonce */
u8 Snonce[WPA_NONCE_LEN]; /* Initiator Nonce */
/* followed by optional elements */
} STRUCT_PACKED;
struct wpa_tdls_timeoutie {
u8 ie_type; /* Timeout IE */
u8 ie_len;
u8 interval_type;
u8 value[TDLS_TIMEOUT_LEN];
} STRUCT_PACKED;
struct wpa_tdls_lnkid {
u8 ie_type; /* Link Identifier IE */
u8 ie_len;
u8 bssid[ETH_ALEN];
u8 init_sta[ETH_ALEN];
u8 resp_sta[ETH_ALEN];
} STRUCT_PACKED;
/* TDLS frame headers as per IEEE Std 802.11z-2010 */
struct wpa_tdls_frame {
u8 payloadtype; /* IEEE80211_TDLS_RFTYPE */
u8 category; /* Category */
u8 action; /* Action (enum tdls_frame_type) */
} STRUCT_PACKED;
static u8 * wpa_add_tdls_timeoutie(u8 *pos, u8 *ie, size_t ie_len, u32 tsecs);
static void wpa_tdls_smkretry_timeout(void *eloop_ctx, void *timeout_ctx);
static void wpa_tdls_peer_free(struct wpa_sm *sm, struct wpa_tdls_peer *peer);
#define TDLS_MAX_IE_LEN 80
struct wpa_tdls_peer {
struct wpa_tdls_peer *next;
int initiator; /* whether this end was initator for SMK handshake */
u8 addr[ETH_ALEN]; /* other end MAC address */
u8 inonce[WPA_NONCE_LEN]; /* Initiator Nonce */
u8 pnonce[WPA_NONCE_LEN]; /* Peer Nonce */
u8 rsnie_i[TDLS_MAX_IE_LEN]; /* Initiator RSN IE */
size_t rsnie_i_len;
u8 rsnie_p[TDLS_MAX_IE_LEN]; /* Peer RSN IE */
size_t rsnie_p_len;
u32 lifetime;
int cipher; /* Selected cipher (WPA_CIPHER_*) */
#define TDLS_LNKID_LEN 20 /* T+L+V(18-octet) */
u8 lnkid[TDLS_LNKID_LEN];
u8 dtoken;
struct tpk {
u8 kck[16]; /* TPK-KCK */
u8 tk[16]; /* TPK-TK; assuming only CCMP will be used */
} tpk;
int tpk_set;
int tpk_success;
struct smk_timer {
u8 dest[ETH_ALEN];
int count; /* Retry Count: dot11RSNAConfigSMKUpdateCount
*/
int timer; /* Timeout: 2000 milliseconds */
u8 action_code; /* TDLS frame type */
u8 dialog_token;
u16 status_code;
int buf_len; /* length of SMK message for retransmission */
u8 *buf; /* buffer for SMK message */
} sm_tmr;
};
static int wpa_tdls_get_privacy(struct wpa_sm *sm)
{
/*
* Get info needed from supplicant to check if the current BSS supports
* security. Other than OPEN mode, rest are considered secured
* WEP/WPA/WPA2 hence TDLS frames are processed for TPK handshake.
*/
return sm->pairwise_cipher != WPA_CIPHER_NONE;
}
static u8 * wpa_add_ie(u8 *pos, const u8 *ie, size_t ie_len)
{
os_memcpy(pos, ie, ie_len);
return pos + ie_len;
}
static int wpa_tdls_del_key(struct wpa_sm *sm, struct wpa_tdls_peer *peer)
{
if (wpa_sm_set_key(sm, WPA_ALG_NONE, peer->addr,
0, 0, NULL, 0, NULL, 0) < 0) {
wpa_printf(MSG_WARNING, "TDLS: Failed to delete PTK-TK from "
"the driver");
return -1;
}
return 0;
}
static int wpa_tdls_set_key(struct wpa_sm *sm, struct wpa_tdls_peer *peer)
{
u8 key_len;
u8 rsc[6];
enum wpa_alg alg;
os_memset(rsc, 0, 6);
switch (peer->cipher) {
case WPA_CIPHER_CCMP:
alg = WPA_ALG_CCMP;
key_len = 16;
break;
case WPA_CIPHER_NONE:
wpa_printf(MSG_DEBUG, "WPA: Pairwise Cipher Suite: "
"NONE - do not use pairwise keys");
return -1;
default:
wpa_printf(MSG_WARNING, "WPA: Unsupported pairwise cipher %d",
sm->pairwise_cipher);
return -1;
}
if (wpa_sm_set_key(sm, alg, peer->addr, -1, 1,
rsc, sizeof(rsc), peer->tpk.tk, key_len) < 0) {
wpa_printf(MSG_WARNING, "RSN: Failed to set TPK to the "
"driver");
return -1;
}
return 0;
}
static int wpa_tdls_send_tpk_msg(struct wpa_sm *sm, const u8 *dst,
u8 action_code, u8 dialog_token,
u16 status_code, const u8 *buf, size_t len)
{
return wpa_sm_send_tdls_mgmt(sm, dst, action_code, dialog_token,
status_code, buf, len);
}
static int wpa_tdls_smk_send(struct wpa_sm *sm, const u8 *dest, u8 action_code,
u8 dialog_token, u16 status_code,
const u8 *msg, size_t msg_len)
{
struct wpa_tdls_peer *peer;
wpa_printf(MSG_DEBUG, "TDLS: SMK Send dest=" MACSTR " action_code=%u "
"dialog_token=%u status_code=%u msg_len=%u",
MAC2STR(dest), action_code, dialog_token, status_code,
(unsigned int) msg_len);
if (wpa_tdls_send_tpk_msg(sm, dest, action_code, dialog_token,
status_code, msg, msg_len)) {
wpa_printf(MSG_INFO, "TDLS: Failed to send message "
"(action_code=%u)", action_code);
return -1;
}
if (action_code == WLAN_TDLS_SETUP_CONFIRM ||
action_code == WLAN_TDLS_TEARDOWN)
return 0; /* No retries */
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, dest, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching entry found for "
"retry " MACSTR, MAC2STR(dest));
return 0;
}
eloop_cancel_timeout(wpa_tdls_smkretry_timeout, sm, peer);
peer->sm_tmr.count = SMK_RETRY_COUNT;
peer->sm_tmr.timer = SMK_TIMEOUT; /* value in milliseconds */
/* Copy message to resend on timeout */
os_memcpy(peer->sm_tmr.dest, dest, ETH_ALEN);
peer->sm_tmr.action_code = action_code;
peer->sm_tmr.dialog_token = dialog_token;
peer->sm_tmr.status_code = status_code;
peer->sm_tmr.buf_len = msg_len;
os_free(peer->sm_tmr.buf);
peer->sm_tmr.buf = os_malloc(msg_len);
if (peer->sm_tmr.buf == NULL)
return -1;
os_memcpy(peer->sm_tmr.buf, msg, msg_len);
wpa_printf(MSG_DEBUG, "TDLS: Retry timeout registered "
"(action_code=%u)", action_code);
eloop_register_timeout(peer->sm_tmr.timer / 1000, 0,
wpa_tdls_smkretry_timeout, sm, peer);
return 0;
}
static void tdls_clear_peer(struct wpa_sm *sm, struct wpa_tdls_peer *peer)
{
u8 mac[ETH_ALEN];
struct wpa_tdls_peer *tmp;
os_memcpy(mac, peer->addr, ETH_ALEN);
tmp = peer->next;
peer->initiator = 0;
eloop_cancel_timeout(wpa_tdls_smkretry_timeout, sm, peer);
os_free(peer->sm_tmr.buf);
/* reset all */
os_memset(peer, 0, sizeof(*peer));
/* restore things */
os_memcpy(peer->addr, mac, ETH_ALEN);
peer->next = tmp;
}
static void wpa_tdls_smkretry_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_sm *sm = eloop_ctx;
struct wpa_tdls_peer *peer = timeout_ctx;
if (peer->sm_tmr.count) {
peer->sm_tmr.count--;
peer->sm_tmr.timer = SMK_TIMEOUT; /* value in milliseconds */
wpa_printf(MSG_INFO, "TDLS: Retrying sending of message "
"(action_code=%u)",
peer->sm_tmr.action_code);
if (peer->sm_tmr.buf == NULL) {
wpa_printf(MSG_INFO, "TDLS: No retry buffer available "
"for action_code=%u",
peer->sm_tmr.action_code);
eloop_cancel_timeout(wpa_tdls_smkretry_timeout, sm,
peer);
return;
}
/* resend TPK Handshake Message to Peer */
if (wpa_tdls_send_tpk_msg(sm, peer->sm_tmr.dest,
peer->sm_tmr.action_code,
peer->sm_tmr.dialog_token,
peer->sm_tmr.status_code,
peer->sm_tmr.buf,
peer->sm_tmr.buf_len)) {
wpa_printf(MSG_INFO, "TDLS: Failed to retry "
"transmission");
}
eloop_cancel_timeout(wpa_tdls_smkretry_timeout, sm, peer);
eloop_register_timeout(peer->sm_tmr.timer / 1000, 0,
wpa_tdls_smkretry_timeout, sm, peer);
} else {
wpa_printf(MSG_INFO, "Sending Tear_Down Request");
wpa_sm_tdls_oper(sm, TDLS_TEARDOWN, peer->addr);
wpa_printf(MSG_INFO, "Clearing SM: Peerkey(" MACSTR ")",
MAC2STR(peer->addr));
eloop_cancel_timeout(wpa_tdls_smkretry_timeout, sm, peer);
/* clear the Peerkey statemachine */
wpa_tdls_peer_free(sm, peer);
}
}
static void wpa_tdls_smkretry_timeout_cancel(struct wpa_sm *sm,
struct wpa_tdls_peer *peer,
u8 action_code)
{
if (action_code == peer->sm_tmr.action_code) {
wpa_printf(MSG_DEBUG, "TDLS: Retry timeout cancelled for "
"action_code=%u", action_code);
/* Cancel Timeout registered */
eloop_cancel_timeout(wpa_tdls_smkretry_timeout, sm, peer);
/* free all resources meant for retry */
os_free(peer->sm_tmr.buf);
peer->sm_tmr.buf = NULL;
peer->sm_tmr.count = 0;
peer->sm_tmr.timer = 0;
peer->sm_tmr.buf_len = 0;
peer->sm_tmr.action_code = 0xff;
} else {
wpa_printf(MSG_INFO, "TDLS: Error in cancelling retry timeout "
"(Unknown action_code=%u)", action_code);
}
}
static void wpa_tdls_generate_tpk(struct wpa_tdls_peer *peer,
const u8 *own_addr, const u8 *bssid)
{
u8 key_input[SHA256_MAC_LEN];
const u8 *nonce[2];
size_t len[2];
u8 data[3 * ETH_ALEN];
/* 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(peer->inonce, peer->pnonce, WPA_NONCE_LEN) < 0) {
nonce[0] = peer->inonce;
nonce[1] = peer->pnonce;
} else {
nonce[0] = peer->pnonce;
nonce[1] = peer->inonce;
}
wpa_hexdump(MSG_DEBUG, "TDLS: min(Nonce)", nonce[0], WPA_NONCE_LEN);
wpa_hexdump(MSG_DEBUG, "TDLS: max(Nonce)", nonce[1], WPA_NONCE_LEN);
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(own_addr, peer->addr, ETH_ALEN) < 0) {
os_memcpy(data, own_addr, ETH_ALEN);
os_memcpy(data + ETH_ALEN, peer->addr, ETH_ALEN);
} else {
os_memcpy(data, peer->addr, ETH_ALEN);
os_memcpy(data + ETH_ALEN, own_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 *) &peer->tpk, sizeof(peer->tpk));
wpa_hexdump_key(MSG_DEBUG, "TDLS: TPK-KCK",
peer->tpk.kck, sizeof(peer->tpk.kck));
wpa_hexdump_key(MSG_DEBUG, "TDLS: TPK-TK",
peer->tpk.tk, sizeof(peer->tpk.tk));
peer->tpk_set = 1;
}
/**
* wpa_tdls_ftie_mic - Calculate TDLS FTIE MIC
* @kck: TPK-KCK
* @lnkid: Pointer to the beginning of Link Identifier IE
* @rsnie: Pointer to the beginning of RSN IE used for handshake
* @timeoutie: Pointer to the beginning of Timeout IE used for handshake
* @ftie: Pointer to the beginning of FT IE
* @mic: Pointer for writing MIC
*
* Calculate MIC for TDLS frame.
*/
static int wpa_tdls_ftie_mic(const u8 *kck, u8 trans_seq, const u8 *lnkid,
const u8 *rsnie, const u8 *timeoutie,
const u8 *ftie, u8 *mic)
{
u8 *buf, *pos;
struct wpa_tdls_ftie *_ftie;
const struct wpa_tdls_lnkid *_lnkid;
int ret;
int len = 2 * ETH_ALEN + 1 + 2 + lnkid[1] + 2 + rsnie[1] +
2 + timeoutie[1] + 2 + ftie[1];
buf = os_zalloc(len);
if (!buf) {
wpa_printf(MSG_WARNING, "TDLS: No memory for MIC calculation");
return -1;
}
pos = buf;
_lnkid = (const struct wpa_tdls_lnkid *) lnkid;
/* 1) TDLS initiator STA MAC address */
os_memcpy(pos, _lnkid->init_sta, ETH_ALEN);
pos += ETH_ALEN;
/* 2) TDLS responder STA MAC address */
os_memcpy(pos, _lnkid->resp_sta, ETH_ALEN);
pos += ETH_ALEN;
/* 3) Transaction Sequence number */
*pos++ = trans_seq;
/* 4) Link Identifier IE */
os_memcpy(pos, lnkid, 2 + lnkid[1]);
pos += 2 + lnkid[1];
/* 5) RSN IE */
os_memcpy(pos, rsnie, 2 + rsnie[1]);
pos += 2 + rsnie[1];
/* 6) Timeout Interval IE */
os_memcpy(pos, timeoutie, 2 + timeoutie[1]);
pos += 2 + timeoutie[1];
/* 7) FTIE, with the MIC field of the FTIE set to 0 */
os_memcpy(pos, ftie, 2 + ftie[1]);
_ftie = (struct wpa_tdls_ftie *) pos;
os_memset(_ftie->mic, 0, TDLS_MIC_LEN);
pos += 2 + ftie[1];
wpa_hexdump(MSG_DEBUG, "TDLS: Data for FTIE MIC", buf, pos - buf);
wpa_hexdump_key(MSG_DEBUG, "TDLS: KCK", kck, 16);
ret = omac1_aes_128(kck, buf, pos - buf, mic);
os_free(buf);
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE MIC", mic, 16);
return ret;
}
/**
* wpa_tdls_key_mic_teardown - Calculate TDLS FTIE MIC for Teardown frame
* @kck: TPK-KCK
* @trans_seq: Transaction Sequence Number (4 - Teardown)
* @rcode: Reason code for Teardown
* @dtoken: Dialogue Token used for that particular link
* @lnkid: Pointer to the beginning of Link Identifier IE
* @ftie: Pointer to the beginning of FT IE
* @mic: Pointer for writing MIC
*
* Calculate MIC for TDLS frame.
*/
static int wpa_tdls_key_mic_teardown(const u8 *kck, u8 trans_seq, u16 rcode,
u8 dtoken, const u8 *lnkid,
const u8 *ftie, u8 *mic)
{
u8 *buf, *pos;
struct wpa_tdls_ftie *_ftie;
int ret;
int len;
if (lnkid == NULL)
return -1;
len = 2 + lnkid[1] + sizeof(rcode) + sizeof(dtoken) +
sizeof(trans_seq) + 2 + ftie[1];
buf = os_zalloc(len);
if (!buf) {
wpa_printf(MSG_WARNING, "TDLS: No memory for MIC calculation");
return -1;
}
pos = buf;
/* 1) Link Identifier IE */
os_memcpy(pos, lnkid, 2 + lnkid[1]);
pos += 2 + lnkid[1];
/* 2) Reason Code */
WPA_PUT_LE16(pos, rcode);
pos += sizeof(rcode);
/* 3) Dialog token */
*pos++ = dtoken;
/* 4) Transaction Sequence number */
*pos++ = trans_seq;
/* 7) FTIE, with the MIC field of the FTIE set to 0 */
os_memcpy(pos, ftie, 2 + ftie[1]);
_ftie = (struct wpa_tdls_ftie *) pos;
os_memset(_ftie->mic, 0, TDLS_MIC_LEN);
pos += 2 + ftie[1];
wpa_hexdump(MSG_DEBUG, "TDLS: Data for FTIE MIC", buf, pos - buf);
wpa_hexdump_key(MSG_DEBUG, "TDLS: KCK", kck, 16);
ret = omac1_aes_128(kck, buf, pos - buf, mic);
os_free(buf);
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE MIC", mic, 16);
return ret;
}
static int wpa_supplicant_verify_tdls_mic(u8 trans_seq,
struct wpa_tdls_peer *peer,
const u8 *lnkid, const u8 *timeoutie,
const struct wpa_tdls_ftie *ftie)
{
u8 mic[16];
if (peer->tpk_set) {
wpa_tdls_ftie_mic(peer->tpk.kck, trans_seq, lnkid,
peer->rsnie_p, timeoutie, (u8 *) ftie,
mic);
if (os_memcmp(mic, ftie->mic, 16) != 0) {
wpa_printf(MSG_INFO, "TDLS: Invalid MIC in FTIE - "
"dropping packet");
wpa_hexdump(MSG_DEBUG, "TDLS: Received MIC",
ftie->mic, 16);
wpa_hexdump(MSG_DEBUG, "TDLS: Calculated MIC",
mic, 16);
return -1;
}
} else {
wpa_printf(MSG_WARNING, "TDLS: Could not verify TDLS MIC, "
"TPK not set - dropping packet");
return -1;
}
return 0;
}
static int wpa_supplicant_verify_tdls_mic_teardown(
u8 trans_seq, u16 rcode, u8 dtoken, struct wpa_tdls_peer *peer,
const u8 *lnkid, const struct wpa_tdls_ftie *ftie)
{
u8 mic[16];
if (peer->tpk_set) {
wpa_tdls_key_mic_teardown(peer->tpk.kck, trans_seq, rcode,
dtoken, lnkid, (u8 *) ftie, mic);
if (os_memcmp(mic, ftie->mic, 16) != 0) {
wpa_printf(MSG_INFO, "TDLS: Invalid MIC in Teardown - "
"dropping packet");
return -1;
}
} else {
wpa_printf(MSG_INFO, "TDLS: Could not verify TDLS Teardown "
"MIC, TPK not set - dropping packet");
return -1;
}
return 0;
}
static void wpa_tdls_tpk_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_sm *sm = eloop_ctx;
struct wpa_tdls_peer *peer = timeout_ctx;
/*
* On TPK lifetime expiration, we have an option of either tearing down
* the direct link or trying to re-initiate it. The selection of what
* to do is not strictly speaking controlled by our role in the expired
* link, but for now, use that to select whether to renew or tear down
* the link.
*/
if (peer->initiator) {
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime expired for " MACSTR
" - try to renew", MAC2STR(peer->addr));
wpa_tdls_start(sm, peer->addr);
} else {
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime expired for " MACSTR
" - tear down", MAC2STR(peer->addr));
wpa_sm_tdls_oper(sm, TDLS_TEARDOWN, peer->addr);
}
}
static void wpa_tdls_peer_free(struct wpa_sm *sm, struct wpa_tdls_peer *peer)
{
eloop_cancel_timeout(wpa_tdls_tpk_timeout, sm, peer);
/* need to clear Peerkey SM */
tdls_clear_peer(sm, peer);
//os_free(peer);
}
int wpa_tdls_recv_teardown_notify(struct wpa_sm *sm, const u8 *addr,
u16 reason_code)
{
struct wpa_tdls_peer *peer = NULL;
struct wpa_tdls_ftie *ftie;
struct wpa_tdls_lnkid *lnkid;
u8 dialogue_token = 0;
u8 *rbuf;
int ielen;
u8 *pos;
/* Find the node and free from the list */
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, addr, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching entry found for "
"Teardown " MACSTR, MAC2STR(addr));
return 0;
}
dialogue_token = peer->dtoken;
lnkid = (struct wpa_tdls_lnkid *) &peer->lnkid;
wpa_printf(MSG_DEBUG, "RSN: TDLS Teardown for " MACSTR,
MAC2STR(addr));
ielen = 0;
if (wpa_tdls_get_privacy(sm) && peer->tpk_set && peer->tpk_success) {
/* To add FTIE for Teardown request and compute MIC */
ielen += sizeof(*ftie);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME)
ielen += 170;
#endif /* CONFIG_TDLS_TESTING */
}
rbuf = os_zalloc(ielen + 1);
if (rbuf == NULL)
return -1;
pos = rbuf;
if (!wpa_tdls_get_privacy(sm) || !peer->tpk_set || !peer->tpk_success)
goto skip_ies;
ftie = (struct wpa_tdls_ftie *) pos;
ftie->ie_type = WLAN_EID_FAST_BSS_TRANSITION;
/* Using the recent nonce which should be for CONFIRM frame */
os_memcpy(ftie->Anonce, peer->pnonce, WPA_NONCE_LEN);
os_memcpy(ftie->Snonce, peer->inonce, WPA_NONCE_LEN);
ftie->ie_len = sizeof(struct wpa_tdls_ftie) - 2;
pos = (u8 *) (ftie + 1);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - add extra subelem to "
"FTIE");
ftie->ie_len += 170;
*pos++ = 255; /* FTIE subelem */
*pos++ = 168; /* FTIE subelem length */
}
#endif /* CONFIG_TDLS_TESTING */
wpa_hexdump(MSG_DEBUG, "WPA: FTIE for TDLS Teardown handshake",
(u8 *) ftie, sizeof(*ftie));
/* compute MIC before sending */
wpa_tdls_key_mic_teardown(peer->tpk.kck, 4, reason_code,
dialogue_token, (u8 *) lnkid, (u8 *) ftie,
ftie->mic);
skip_ies:
/* TODO: register for a Timeout handler, if Teardown is not received at
* the other end, then try again another time */
/* request driver to send Teardown using this FTIE */
wpa_tdls_smk_send(sm, addr, WLAN_TDLS_TEARDOWN, 0,
WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED, rbuf,
pos - rbuf);
os_free(rbuf);
/* clear the Peerkey statemachine */
wpa_tdls_peer_free(sm, peer);
return 0;
}
static int wpa_tdls_recv_teardown(struct wpa_sm *sm, const u8 *src_addr,
const u8 *buf, size_t len)
{
struct wpa_tdls_peer *peer = NULL;
struct wpa_tdls_ftie *ftie;
struct wpa_tdls_lnkid *lnkid;
struct wpa_eapol_ie_parse kde;
u16 reason_code;
const u8 *pos;
int ielen;
/* Find the node and free from the list */
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, src_addr, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching entry found for "
"Teardown " MACSTR, MAC2STR(src_addr));
return 0;
}
pos = buf;
pos += 1 /* pkt_type */ + 1 /* Category */ + 1 /* Action */;
reason_code = WPA_GET_LE16(pos);
pos += 2;
wpa_printf(MSG_DEBUG, "TDLS: TDLS Teardown Request from " MACSTR
" (reason code %u)", MAC2STR(src_addr), reason_code);
ielen = len - (pos - buf); /* start of IE in buf */
if (wpa_supplicant_parse_ies((const u8 *) pos, ielen, &kde) < 0) {
wpa_printf(MSG_INFO, "TDLS: Failed to parse IEs in Teardown");
return -1;
}
if (kde.lnkid == NULL || kde.lnkid_len < 3 * ETH_ALEN) {
wpa_printf(MSG_INFO, "TDLS: No Link Identifier IE in TDLS "
"Teardown");
return -1;
}
lnkid = (struct wpa_tdls_lnkid *) kde.lnkid;
if (!wpa_tdls_get_privacy(sm) || !peer->tpk_set || !peer->tpk_success)
goto skip_ftie;
if (kde.ftie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No FTIE in TDLS Teardown");
return -1;
}
ftie = (struct wpa_tdls_ftie *) kde.ftie;
/* Process MIC check to see if TDLS Teardown is right */
if (wpa_supplicant_verify_tdls_mic_teardown(4, reason_code,
peer->dtoken, peer,
(u8 *) lnkid, ftie) < 0) {
wpa_printf(MSG_DEBUG, "TDLS: MIC failure for TDLS "
"Teardown Request from " MACSTR, MAC2STR(src_addr));
#if 0
return -1;
#else
/* TODO: figure out whether this workaround could be disabled
*/
wpa_printf(MSG_DEBUG, "TDLS: Workaround - ignore Teardown MIC "
"failure");
#endif
}
skip_ftie:
/*
* Request the driver to disable the direct link and clear associated
* keys.
*/
wpa_sm_tdls_oper(sm, TDLS_DISABLE_LINK, src_addr);
/* clear the Peerkey statemachine */
wpa_tdls_peer_free(sm, peer);
return 0;
}
/**
* wpa_tdls_send_smk_error - To send suitable TDLS status response with
* appropriate status code mentioning reason for error/failure.
* @dst - MAC addr of Peer station
* @tdls_action - TDLS frame type for which error code is sent
* @status - status code mentioning reason
*/
static int wpa_tdls_send_smk_error(struct wpa_sm *sm, const u8 *dst,
u8 tdls_action, u8 dialog_token, u16 status)
{
return wpa_tdls_smk_send(sm, dst, tdls_action, dialog_token, status,
NULL, 0);
}
static int wpa_tdls_send_tpk_m1(struct wpa_sm *sm,
struct wpa_tdls_peer *peer)
{
size_t buf_len;
struct wpa_tdls_timeoutie timeoutie;
u16 rsn_capab;
struct wpa_tdls_ftie *ftie;
u8 *rbuf, *pos, *count_pos;
u16 count;
struct rsn_ie_hdr *hdr;
if (!wpa_tdls_get_privacy(sm)) {
wpa_printf(MSG_DEBUG, "TDLS: No security used on the link");
peer->rsnie_i_len = 0;
goto skip_rsnie;
}
/*
* TPK Handshake Message 1:
* FTIE: ANonce=0, SNonce=nonce MIC=0, DataKDs=(RSNIE_I,
* Timeout Interval IE))
*/
/* Filling RSN IE */
hdr = (struct rsn_ie_hdr *) peer->rsnie_i;
hdr->elem_id = WLAN_EID_RSN;
WPA_PUT_LE16(hdr->version, RSN_VERSION);
pos = (u8 *) (hdr + 1);
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_NO_GROUP_ADDRESSED);
pos += RSN_SELECTOR_LEN;
count_pos = pos;
pos += 2;
count = 0;
/*
* AES-CCMP is the default Encryption preferred for TDLS, so
* RSN IE is filled only with CCMP CIPHER
* Note: TKIP is not used to encrypt TDLS link.
*
* Regardless of the cipher used on the AP connection, select CCMP
* here.
*/
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
pos += RSN_SELECTOR_LEN;
count++;
WPA_PUT_LE16(count_pos, count);
WPA_PUT_LE16(pos, 1);
pos += 2;
RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_TPK_HANDSHAKE);
pos += RSN_SELECTOR_LEN;
rsn_capab = WPA_CAPABILITY_PEERKEY_ENABLED;
rsn_capab |= RSN_NUM_REPLAY_COUNTERS_16 << 2;
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_ALT_RSN_IE) {
wpa_printf(MSG_DEBUG, "TDLS: Use alternative RSN IE for "
"testing");
rsn_capab = WPA_CAPABILITY_PEERKEY_ENABLED;
}
#endif /* CONFIG_TDLS_TESTING */
WPA_PUT_LE16(pos, rsn_capab);
pos += 2;
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_ALT_RSN_IE) {
/* Number of PMKIDs */
*pos++ = 0x00;
*pos++ = 0x00;
}
#endif /* CONFIG_TDLS_TESTING */
hdr->len = (pos - peer->rsnie_i) - 2;
peer->rsnie_i_len = pos - peer->rsnie_i;
wpa_hexdump(MSG_DEBUG, "TDLS: RSN IE for TPK handshake",
peer->rsnie_i, peer->rsnie_i_len);
skip_rsnie:
buf_len = 0;
if (wpa_tdls_get_privacy(sm))
buf_len += peer->rsnie_i_len + sizeof(struct wpa_tdls_ftie) +
sizeof(struct wpa_tdls_timeoutie);
#ifdef CONFIG_TDLS_TESTING
if (wpa_tdls_get_privacy(sm) &&
(tdls_testing & TDLS_TESTING_LONG_FRAME))
buf_len += 170;
if (tdls_testing & TDLS_TESTING_DIFF_BSSID)
buf_len += sizeof(struct wpa_tdls_lnkid);
#endif /* CONFIG_TDLS_TESTING */
rbuf = os_zalloc(buf_len + 1);
if (rbuf == NULL) {
wpa_tdls_peer_free(sm, peer);
return -1;
}
pos = rbuf;
if (!wpa_tdls_get_privacy(sm))
goto skip_ies;
/* Initiator RSN IE */
pos = wpa_add_ie(pos, peer->rsnie_i, peer->rsnie_i_len);
ftie = (struct wpa_tdls_ftie *) pos;
ftie->ie_type = WLAN_EID_FAST_BSS_TRANSITION;
ftie->ie_len = sizeof(struct wpa_tdls_ftie) - 2;
if (os_get_random(peer->inonce, WPA_NONCE_LEN)) {
wpa_msg(sm->ctx->msg_ctx, MSG_WARNING,
"WPA: Failed to get random data for INonce");
os_free(rbuf);
wpa_tdls_peer_free(sm, peer);
return -1;
}
os_memcpy(ftie->Snonce, peer->inonce, WPA_NONCE_LEN);
wpa_hexdump(MSG_DEBUG, "TDLS: INonce for TPK handshake",
ftie->Snonce, WPA_NONCE_LEN);
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE for TPK Handshake M1",
(u8 *) ftie, sizeof(struct wpa_tdls_ftie));
pos = (u8 *) (ftie + 1);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - add extra subelem to "
"FTIE");
ftie->ie_len += 170;
*pos++ = 255; /* FTIE subelem */
*pos++ = 168; /* FTIE subelem length */
pos += 168;
}
#endif /* CONFIG_TDLS_TESTING */
/* Lifetime */
peer->lifetime = TPK_LIFETIME;
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_SHORT_LIFETIME) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - use short TPK "
"lifetime");
peer->lifetime = 301;
}
#endif /* CONFIG_TDLS_TESTING */
pos = wpa_add_tdls_timeoutie(pos, (u8 *) &timeoutie,
sizeof(timeoutie), peer->lifetime);
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime %u seconds", peer->lifetime);
skip_ies:
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_DIFF_BSSID) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - use incorrect BSSID in "
"Link Identifier");
struct wpa_tdls_lnkid *l = (struct wpa_tdls_lnkid *) pos;
l->ie_type = WLAN_EID_LINK_ID;
l->ie_len = 3 * ETH_ALEN;
os_memcpy(l->bssid, sm->bssid, ETH_ALEN);
l->bssid[5] ^= 0x01;
os_memcpy(l->init_sta, sm->own_addr, ETH_ALEN);
os_memcpy(l->resp_sta, addr, ETH_ALEN);
pos += sizeof(*l);
}
#endif /* CONFIG_TDLS_TESTING */
wpa_printf(MSG_DEBUG, "TDLS: Sending TDLS Setup Request / TPK "
"Handshake Message 1 (peer " MACSTR ")",
MAC2STR(peer->addr));
wpa_tdls_smk_send(sm, peer->addr, WLAN_TDLS_SETUP_REQUEST, 0, 0,
rbuf, pos - rbuf);
os_free(rbuf);
return 0;
}
static int wpa_tdls_send_tpk_m2(struct wpa_sm *sm,
const unsigned char *src_addr, u8 dtoken,
struct wpa_tdls_lnkid *lnkid,
const struct wpa_tdls_peer *peer)
{
u8 *rbuf, *pos;
size_t buf_len;
u32 lifetime;
struct wpa_tdls_timeoutie timeoutie;
struct wpa_tdls_ftie *ftie;
buf_len = 0;
if (wpa_tdls_get_privacy(sm)) {
/* Peer RSN IE, FTIE(Initiator Nonce, Peer nonce), Lifetime */
buf_len += peer->rsnie_i_len + sizeof(struct wpa_tdls_ftie) +
sizeof(struct wpa_tdls_timeoutie);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME)
buf_len += 170;
#endif /* CONFIG_TDLS_TESTING */
}
rbuf = os_zalloc(buf_len + 1);
if (rbuf == NULL)
return -1;
pos = rbuf;
if (!wpa_tdls_get_privacy(sm))
goto skip_ies;
/* Peer RSN IE */
pos = wpa_add_ie(pos, peer->rsnie_p, peer->rsnie_p_len);
ftie = (struct wpa_tdls_ftie *) pos;
ftie->ie_type = WLAN_EID_FAST_BSS_TRANSITION;
/* TODO: ftie->mic_control to set 2-RESPONSE */
os_memcpy(ftie->Anonce, peer->pnonce, WPA_NONCE_LEN);
os_memcpy(ftie->Snonce, peer->inonce, WPA_NONCE_LEN);
ftie->ie_len = sizeof(struct wpa_tdls_ftie) - 2;
wpa_hexdump(MSG_WARNING, "WPA: FTIE for SMK M2 handshake",
(u8 *) ftie, sizeof(*ftie));
pos = (u8 *) (ftie + 1);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - add extra subelem to "
"FTIE");
ftie->ie_len += 170;
*pos++ = 255; /* FTIE subelem */
*pos++ = 168; /* FTIE subelem length */
pos += 168;
}
#endif /* CONFIG_TDLS_TESTING */
/* Lifetime */
lifetime = peer->lifetime;
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_WRONG_LIFETIME_RESP) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - use wrong TPK "
"lifetime in response");
lifetime++;
}
#endif /* CONFIG_TDLS_TESTING */
pos = wpa_add_tdls_timeoutie(pos, (u8 *) &timeoutie,
sizeof(timeoutie), lifetime);
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime %u seconds from initiator",
lifetime);
/* compute MIC before sending */
wpa_tdls_ftie_mic(peer->tpk.kck, 2, (u8 *) lnkid, peer->rsnie_p,
(u8 *) &timeoutie, (u8 *) ftie, ftie->mic);
skip_ies:
wpa_tdls_smk_send(sm, src_addr, WLAN_TDLS_SETUP_RESPONSE, dtoken, 0,
rbuf, pos - rbuf);
os_free(rbuf);
return 0;
}
static int wpa_tdls_send_tpk_m3(struct wpa_sm *sm,
const unsigned char *src_addr, u8 dtoken,
struct wpa_tdls_lnkid *lnkid,
const struct wpa_tdls_peer *peer)
{
u8 *rbuf, *pos;
size_t buf_len;
struct wpa_tdls_ftie *ftie;
struct wpa_tdls_timeoutie timeoutie;
u32 lifetime;
buf_len = 0;
if (wpa_tdls_get_privacy(sm)) {
/* Peer RSN IE, FTIE(Initiator Nonce, Peer nonce), Lifetime */
buf_len += peer->rsnie_i_len + sizeof(struct wpa_tdls_ftie) +
sizeof(struct wpa_tdls_timeoutie);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME)
buf_len += 170;
#endif /* CONFIG_TDLS_TESTING */
}
rbuf = os_zalloc(buf_len + 1);
if (rbuf == NULL)
return -1;
pos = rbuf;
if (!wpa_tdls_get_privacy(sm))
goto skip_ies;
/* Peer RSN IE */
pos = wpa_add_ie(pos, peer->rsnie_p, peer->rsnie_p_len);
ftie = (struct wpa_tdls_ftie *) pos;
ftie->ie_type = WLAN_EID_FAST_BSS_TRANSITION;
/*TODO: ftie->mic_control to set 3-CONFIRM */
os_memcpy(ftie->Anonce, peer->pnonce, WPA_NONCE_LEN);
os_memcpy(ftie->Snonce, peer->inonce, WPA_NONCE_LEN);
ftie->ie_len = sizeof(struct wpa_tdls_ftie) - 2;
pos = (u8 *) (ftie + 1);
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_LONG_FRAME) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - add extra subelem to "
"FTIE");
ftie->ie_len += 170;
*pos++ = 255; /* FTIE subelem */
*pos++ = 168; /* FTIE subelem length */
pos += 168;
}
#endif /* CONFIG_TDLS_TESTING */
/* Lifetime */
lifetime = peer->lifetime;
#ifdef CONFIG_TDLS_TESTING
if (tdls_testing & TDLS_TESTING_WRONG_LIFETIME_CONF) {
wpa_printf(MSG_DEBUG, "TDLS: Testing - use wrong TPK "
"lifetime in confirm");
lifetime++;
}
#endif /* CONFIG_TDLS_TESTING */
pos = wpa_add_tdls_timeoutie(pos, (u8 *) &timeoutie,
sizeof(timeoutie), lifetime);
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime %u seconds",
lifetime);
/* compute MIC before sending */
wpa_tdls_ftie_mic(peer->tpk.kck, 3, (u8 *) lnkid, peer->rsnie_p,
(u8 *) &timeoutie, (u8 *) ftie, ftie->mic);
skip_ies:
wpa_tdls_smk_send(sm, src_addr, WLAN_TDLS_SETUP_CONFIRM, dtoken, 0,
rbuf, pos - rbuf);
os_free(rbuf);
return 0;
}
static int wpa_tdls_process_tpk_m1(struct wpa_sm *sm, const u8 *src_addr,
const u8 *buf, size_t len)
{
struct wpa_tdls_peer *peer;
struct wpa_eapol_ie_parse kde;
struct wpa_ie_data ie;
int cipher;
const u8 *cpos;
struct wpa_tdls_ftie *ftie = NULL;
struct wpa_tdls_timeoutie *timeoutie;
struct wpa_tdls_lnkid *lnkid;
u32 lifetime = 0;
#if 0
struct rsn_ie_hdr *hdr;
u8 *pos;
u16 rsn_capab;
u16 rsn_ver;
#endif
u8 dtoken;
u16 ielen;
cpos = buf;
cpos += 1 /* pkt_type */ + 1 /* Category */ + 1 /* Action */;
/* driver had already verified the frame format */
dtoken = *cpos++; /* dialogue token */
wpa_printf(MSG_INFO, "TDLS: Dialogue Token in TPK M1 %d",
dtoken);
cpos += 2; /* capability information */
ielen = len - (cpos - buf); /* start of IE in buf */
if (wpa_supplicant_parse_ies(cpos, ielen, &kde) < 0) {
wpa_printf(MSG_INFO, "TDLS: Failed to parse KDEs in TPK M1");
return -1;
}
if (kde.lnkid == NULL || kde.lnkid_len < 3 * ETH_ALEN) {
wpa_printf(MSG_INFO, "TDLS: No Link Identifier IE in TPK M1");
return -1;
}
lnkid = (struct wpa_tdls_lnkid *) kde.lnkid;
if (os_memcmp(sm->bssid, lnkid->bssid, ETH_ALEN) != 0) {
wpa_printf(MSG_INFO, "TDLS: TPK M1 from diff BSS");
wpa_tdls_send_smk_error(sm, src_addr, WLAN_TDLS_SETUP_RESPONSE,
dtoken, WLAN_STATUS_NOT_IN_SAME_BSS);
return -1;
}
wpa_printf(MSG_DEBUG, "TDLS: TPK M1 - TPK initiator " MACSTR,
MAC2STR(src_addr));
if (!wpa_tdls_get_privacy(sm))
goto skip_rsn;
if (kde.ftie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No FTIE in TPK M1");
return -1;
}
ftie = (struct wpa_tdls_ftie *) kde.ftie;
if (kde.rsn_ie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No RSN IE in TPK M1");
return -1;
}
if (kde.rsn_ie_len > TDLS_MAX_IE_LEN) {
wpa_printf(MSG_INFO, "TDLS: Too long Initiator RSN IE in "
"TPK M1");
return -1;
}
if (wpa_parse_wpa_ie_rsn(kde.rsn_ie, kde.rsn_ie_len, &ie) < 0) {
wpa_printf(MSG_INFO, "TDLS: Failed to parse RSN IE in TPK M1");
return -1;
}
cipher = ie.pairwise_cipher;
if (cipher & WPA_CIPHER_CCMP) {
wpa_printf(MSG_DEBUG, "TDLS: Using CCMP for direct link");
cipher = WPA_CIPHER_CCMP;
} else {
wpa_printf(MSG_INFO, "TDLS: No acceptable cipher in TPK M1");
wpa_tdls_send_smk_error(sm, src_addr, WLAN_TDLS_SETUP_RESPONSE,
dtoken,
WLAN_STATUS_PAIRWISE_CIPHER_NOT_VALID);
return -1;
}
skip_rsn:
/* Find existing entry and if found, use that instead of adding
* a new one; how to handle the case where both ends initiate at the
* same time? */
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, src_addr, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching entry found for "
"peer, creating one for " MACSTR,
MAC2STR(src_addr));
peer = os_malloc(sizeof(*peer));
if (peer == NULL)
return -1;
os_memset(peer, 0, sizeof(*peer));
os_memcpy(peer->addr, src_addr, ETH_ALEN);
peer->next = sm->tdls;
sm->tdls = peer;
} else {
/*
* An entry is already present, so check if a TPK_M1 Request
* had been sent.
* If so compare MAC address and let
* - greater MAC continue to be initiator
* - other MAC be Peer and process the Req.
*/
if (peer->initiator) {
if (os_memcmp(sm->own_addr, src_addr, ETH_ALEN) > 0) {
wpa_printf(MSG_DEBUG, "TDLS: Dropping Request "
"from peer with smaller address "
MACSTR, MAC2STR(src_addr));
return -1;
} else {
/*
* If smaller node then accept the packet,
* clear values and get ready to process this
* Req.
*/
wpa_printf(MSG_DEBUG, "TDLS: Accepting "
"Request from peer " MACSTR,
MAC2STR(src_addr));
/* clear sm info and preserve the list */
wpa_tdls_peer_free(sm, peer);
}
}
}
peer->initiator = 0; /* Need to check */
peer->dtoken = dtoken;
os_memcpy(peer->lnkid, (u8 *) lnkid, sizeof(struct wpa_tdls_lnkid));
if (!wpa_tdls_get_privacy(sm)) {
peer->rsnie_i_len = 0;
peer->rsnie_p_len = 0;
peer->cipher = WPA_CIPHER_NONE;
goto skip_rsn_check;
}
os_memcpy(peer->inonce, ftie->Snonce, WPA_NONCE_LEN);
os_memcpy(peer->rsnie_i, kde.rsn_ie, kde.rsn_ie_len);
peer->rsnie_i_len = kde.rsn_ie_len;
peer->cipher = cipher;
if (os_get_random(peer->pnonce, WPA_NONCE_LEN)) {
wpa_msg(sm->ctx->ctx, MSG_WARNING,
"TDLS: Failed to get random data for PNonce");
wpa_tdls_peer_free(sm, peer);
return -1;
}
#if 0
/* get version info from RSNIE received from Peer */
hdr = (struct rsn_ie_hdr *) kde.rsn_ie;
rsn_ver = WPA_GET_LE16(hdr->version);
/* use min(peer's version, out version) */
if (rsn_ver > RSN_VERSION)
rsn_ver = RSN_VERSION;
hdr = (struct rsn_ie_hdr *) peer->rsnie_p;
hdr->elem_id = WLAN_EID_RSN;
WPA_PUT_LE16(hdr->version, rsn_ver);
pos = (u8 *) (hdr + 1);
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_NO_GROUP_ADDRESSED);
pos += RSN_SELECTOR_LEN;
/* Include only the selected cipher in pairwise cipher suite */
WPA_PUT_LE16(pos, 1);
pos += 2;
if (cipher == WPA_CIPHER_CCMP)
RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
pos += RSN_SELECTOR_LEN;
WPA_PUT_LE16(pos, 1);
pos += 2;
RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_TPK_HANDSHAKE);
pos += RSN_SELECTOR_LEN;
rsn_capab = WPA_CAPABILITY_PEERKEY_ENABLED;
rsn_capab |= RSN_NUM_REPLAY_COUNTERS_16 << 2;
WPA_PUT_LE16(pos, rsn_capab);
pos += 2;
hdr->len = (pos - peer->rsnie_p) - 2;
peer->rsnie_p_len = pos - peer->rsnie_p;
#endif
/* temp fix: validation of RSNIE later */
os_memcpy(peer->rsnie_p, peer->rsnie_i, peer->rsnie_i_len);
peer->rsnie_p_len = peer->rsnie_i_len;
wpa_hexdump(MSG_DEBUG, "TDLS: RSN IE for PTK handshake",
peer->rsnie_p, peer->rsnie_p_len);
/* Lifetime */
if (kde.key_lifetime == NULL) {
wpa_printf(MSG_INFO, "TDLS: No Key Lifetime IE in TPK M1");
return -1;
}
timeoutie = (struct wpa_tdls_timeoutie *) kde.key_lifetime;
lifetime = WPA_GET_LE32(timeoutie->value);
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime %u seconds", lifetime);
if (lifetime < 300)
lifetime = 300; /* minimum seconds */
peer->lifetime = lifetime;
/* generate SMK using Nonce */
wpa_tdls_generate_tpk(peer, sm->own_addr, sm->bssid);
skip_rsn_check:
wpa_printf(MSG_DEBUG, "TDLS: Sending TDLS Setup Response / TPK M2");
wpa_tdls_send_tpk_m2(sm, src_addr, dtoken, lnkid, peer);
return 0;
}
static void wpa_tdls_enable_link(struct wpa_sm *sm, struct wpa_tdls_peer *peer)
{
peer->tpk_success = 1;
eloop_cancel_timeout(wpa_tdls_tpk_timeout, sm, peer);
if (wpa_tdls_get_privacy(sm)) {
eloop_register_timeout(peer->lifetime, 0, wpa_tdls_tpk_timeout,
sm, peer);
}
wpa_sm_tdls_oper(sm, TDLS_ENABLE_LINK, peer->addr);
}
static int wpa_tdls_process_tpk_m2(struct wpa_sm *sm, const u8 *src_addr,
const u8 *buf, size_t len)
{
struct wpa_tdls_peer *peer;
struct wpa_eapol_ie_parse kde;
struct wpa_ie_data ie;
int cipher;
struct wpa_tdls_ftie *ftie;
struct wpa_tdls_timeoutie *timeoutie;
struct wpa_tdls_lnkid *lnkid;
u32 lifetime;
u8 dtoken;
int ielen;
u16 status;
const u8 *pos;
wpa_printf(MSG_DEBUG, "TDLS: Received TDLS Setup Response / TPK M2 "
"(Peer " MACSTR ")", MAC2STR(src_addr));
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, src_addr, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching peer found for "
"TPK M2: " MACSTR, MAC2STR(src_addr));
return -1;
}
wpa_tdls_smkretry_timeout_cancel(sm, peer, WLAN_TDLS_SETUP_REQUEST);
if (len < 3 + 2 + 1)
return -1;
pos = buf;
pos += 1 /* pkt_type */ + 1 /* Category */ + 1 /* Action */;
status = WPA_GET_LE16(pos);
pos += 2 /* status code */;
if (status != 0) {
wpa_printf(MSG_INFO, "TDLS: Status code in TPK M2: %u",
status);
return -1;
}
/* TODO: need to verify dialog token matches here or in kernel */
dtoken = *pos++; /* dialogue token */
wpa_printf(MSG_DEBUG, "TDLS: Dialogue Token in TPK M2 %d", dtoken);
if (len < 3 + 2 + 1 + 2)
return -1;
pos += 2; /* capability information */
ielen = len - (pos - buf); /* start of IE in buf */
if (wpa_supplicant_parse_ies(pos, ielen, &kde) < 0) {
wpa_printf(MSG_INFO, "TDLS: Failed to parse IEs in TPK M2");
return -1;
}
if (kde.lnkid == NULL || kde.lnkid_len < 3 * ETH_ALEN) {
wpa_printf(MSG_INFO, "TDLS: No valid Link Identifier IE in "
"TPK M2");
return -1;
}
wpa_hexdump(MSG_DEBUG, "TDLS: Link ID Received from TPK M2",
kde.lnkid, kde.lnkid_len);
lnkid = (struct wpa_tdls_lnkid *) kde.lnkid;
if (os_memcmp(sm->bssid, lnkid->bssid, ETH_ALEN) != 0) {
wpa_printf(MSG_INFO, "TDLS: TPK M2 from different BSS");
wpa_tdls_send_smk_error(sm, src_addr, WLAN_TDLS_SETUP_CONFIRM,
dtoken, WLAN_STATUS_NOT_IN_SAME_BSS);
return -1;
}
if (!wpa_tdls_get_privacy(sm)) {
peer->rsnie_p_len = 0;
peer->cipher = WPA_CIPHER_NONE;
goto skip_rsn;
}
if (kde.rsn_ie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No RSN IE in TPK M2");
return -1;
}
wpa_hexdump(MSG_DEBUG, "TDLS: RSNIE Received from TPK M2",
kde.rsn_ie, kde.rsn_ie_len);
if (kde.rsn_ie_len != peer->rsnie_i_len ||
os_memcmp(peer->rsnie_i, kde.rsn_ie, peer->rsnie_i_len) != 0) {
wpa_printf(MSG_INFO, "TDLS: RSN IE in TPK M2 does "
"not match with RSN IE used in TPK M1");
wpa_hexdump(MSG_DEBUG, "TDLS: RSN IE Sent in TPK M1",
peer->rsnie_i, peer->rsnie_i_len);
wpa_hexdump(MSG_DEBUG, "TDLS: RSN IE Received from TPK M2",
kde.rsn_ie, kde.rsn_ie_len);
wpa_tdls_send_smk_error(
sm, src_addr,
WLAN_TDLS_SETUP_CONFIRM, dtoken,
WLAN_STATUS_UNSUPPORTED_RSN_IE_VERSION);
return -1;
}
if (wpa_parse_wpa_ie_rsn(kde.rsn_ie, kde.rsn_ie_len, &ie) < 0) {
wpa_printf(MSG_INFO, "TDLS: Failed to parse RSN IE in TPK M2");
return -1;
}
cipher = ie.pairwise_cipher;
if (cipher & WPA_CIPHER_CCMP) {
wpa_printf(MSG_DEBUG, "TDLS: Using CCMP for direct link");
cipher = WPA_CIPHER_CCMP;
} else {
wpa_printf(MSG_INFO, "TDLS: No acceptable cipher in TPK M2");
wpa_tdls_send_smk_error(sm, src_addr, WLAN_TDLS_SETUP_CONFIRM,
dtoken,
WLAN_STATUS_PAIRWISE_CIPHER_NOT_VALID);
return -1;
}
if (kde.ftie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No FTIE in TPK M2");
return -1;
}
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE Received from TPK M2",
kde.ftie, sizeof(*ftie));
ftie = (struct wpa_tdls_ftie *) kde.ftie;
if (!os_memcmp(peer->inonce, ftie->Snonce, WPA_NONCE_LEN) == 0) {
wpa_printf(MSG_INFO, "TDLS: Key Nonce in TPK M2 does "
"not match with INonce used in TPK M1");
return -1;
}
/* P-Nonce and RSN_IE */
os_memcpy(peer->lnkid, (u8 *) lnkid, sizeof(struct wpa_tdls_lnkid));
os_memcpy(peer->pnonce, ftie->Anonce, WPA_NONCE_LEN);
os_memcpy(peer->rsnie_p, kde.rsn_ie, kde.rsn_ie_len);
peer->rsnie_p_len = kde.rsn_ie_len;
peer->cipher = cipher;
/* Lifetime */
if (kde.key_lifetime == NULL) {
wpa_printf(MSG_INFO, "TDLS: No Key Lifetime IE in TPK M2");
return -1;
}
timeoutie = (struct wpa_tdls_timeoutie *) kde.key_lifetime;
lifetime = WPA_GET_LE32(timeoutie->value);
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime %u seconds in TPK M2",
lifetime);
if (lifetime != peer->lifetime) {
wpa_printf(MSG_INFO, "TDLS: Unexpected TPK lifetime %u in "
"TPK M2 (expected %u)", lifetime, peer->lifetime);
wpa_tdls_send_smk_error(sm, src_addr, WLAN_TDLS_SETUP_CONFIRM,
dtoken,
WLAN_STATUS_UNACCEPTABLE_LIFETIME);
return -1;
}
/* generate SMK using Nonce */
wpa_tdls_generate_tpk(peer, sm->own_addr, sm->bssid);
/* Process MIC check to see if TPK M2 is right */
if (wpa_supplicant_verify_tdls_mic(2, peer, (u8 *) lnkid,
(u8 *) timeoutie, ftie) < 0) {
wpa_tdls_del_key(sm, peer);
wpa_tdls_peer_free(sm, peer);
return -1;
}
wpa_tdls_set_key(sm, peer);
skip_rsn:
peer->dtoken = dtoken;
wpa_printf(MSG_DEBUG, "TDLS: Sending TDLS Setup Confirm / "
"TPK Handshake Message 3");
wpa_tdls_send_tpk_m3(sm, src_addr, dtoken, lnkid, peer);
wpa_tdls_enable_link(sm, peer);
return 0;
}
static int wpa_tdls_process_tpk_m3(struct wpa_sm *sm, const u8 *src_addr,
const u8 *buf, size_t len)
{
struct wpa_tdls_peer *peer;
struct wpa_eapol_ie_parse kde;
struct wpa_tdls_ftie *ftie;
struct wpa_tdls_timeoutie *timeoutie;
struct wpa_tdls_lnkid *lnkid;
int ielen;
u16 status;
const u8 *pos;
u32 lifetime;
wpa_printf(MSG_DEBUG, "RSN: Received TPK M3 (Peer " MACSTR ")",
MAC2STR(src_addr));
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, src_addr, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching peer found for "
"TPK M3: " MACSTR, MAC2STR(src_addr));
return -1;
}
wpa_tdls_smkretry_timeout_cancel(sm, peer, WLAN_TDLS_SETUP_RESPONSE);
pos = buf;
pos += 1 /* pkt_type */ + 1 /* Category */ + 1 /* Action */;
status = WPA_GET_LE16(pos);
if (status != 0) {
wpa_printf(MSG_INFO, "TDLS: Status code in TPK M3: %u",
status);
return -1;
}
pos += 2 /* status code */ + 1 /* dialogue token */;
ielen = len - (pos - buf); /* start of IE in buf */
if (wpa_supplicant_parse_ies((const u8 *) pos, ielen, &kde) < 0) {
wpa_printf(MSG_INFO, "TDLS: Failed to parse KDEs in TPK M3");
return -1;
}
if (kde.lnkid == NULL || kde.lnkid_len < 3 * ETH_ALEN) {
wpa_printf(MSG_INFO, "TDLS: No Link Identifier IE in TPK M3");
return -1;
}
wpa_hexdump(MSG_DEBUG, "TDLS: Link ID Received from TPK M3",
(u8 *) kde.lnkid, kde.lnkid_len);
lnkid = (struct wpa_tdls_lnkid *) kde.lnkid;
if (os_memcmp(sm->bssid, lnkid->bssid, ETH_ALEN) != 0) {
wpa_printf(MSG_INFO, "TDLS: TPK M3 from diff BSS");
return -1;
}
if (!wpa_tdls_get_privacy(sm))
goto skip_rsn;
if (kde.ftie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No FTIE in TPK M3");
return -1;
}
wpa_hexdump(MSG_DEBUG, "TDLS: FTIE Received from TPK M3",
(u8 *) ftie, sizeof(*ftie));
ftie = (struct wpa_tdls_ftie *) kde.ftie;
if (kde.rsn_ie == NULL) {
wpa_printf(MSG_INFO, "TDLS: No RSN IE KDE in TPK M3");
return -1;
}
wpa_hexdump(MSG_DEBUG, "TDLS: RSNIE Received from TPK M3",
kde.rsn_ie, kde.rsn_ie_len);
if (!os_memcmp(peer->pnonce, ftie->Anonce, WPA_NONCE_LEN) == 0) {
wpa_printf(MSG_INFO, "TDLS: PNonce in TPK M3 does "
"not match with PNonce used in TPK M2");
return -1;
}
if (!os_memcmp(peer->inonce, ftie->Snonce, WPA_NONCE_LEN) == 0) {
wpa_printf(MSG_INFO, "TDLS: INonce in TPK M3 did not "
"match with the one received in TPK M1");
return -1;
}
if (kde.key_lifetime == NULL) {
wpa_printf(MSG_INFO, "TDLS: No Key Lifetime IE in TPK M3");
return -1;
}
timeoutie = (struct wpa_tdls_timeoutie *) kde.key_lifetime;
wpa_hexdump(MSG_DEBUG, "TDLS: Timeout IE Received from TPK M3",
(u8 *) timeoutie, sizeof(*timeoutie));
lifetime = WPA_GET_LE32(timeoutie->value);
wpa_printf(MSG_DEBUG, "TDLS: TPK lifetime %u seconds in TPK M3",
lifetime);
if (lifetime != peer->lifetime) {
wpa_printf(MSG_INFO, "TDLS: Unexpected TPK lifetime %u in "
"TPK M3 (expected %u)", lifetime, peer->lifetime);
return -1;
}
if (wpa_supplicant_verify_tdls_mic(3, peer, (u8 *) lnkid,
(u8 *) timeoutie, ftie) < 0) {
wpa_tdls_del_key(sm, peer);
wpa_tdls_peer_free(sm, peer);
return -1;
}
if (wpa_tdls_set_key(sm, peer) < 0)
return -1;
skip_rsn:
wpa_tdls_enable_link(sm, peer);
return 0;
}
static u8 * wpa_add_tdls_timeoutie(u8 *pos, u8 *ie, size_t ie_len, u32 tsecs)
{
struct wpa_tdls_timeoutie *lifetime = (struct wpa_tdls_timeoutie *) ie;
os_memset(lifetime, 0, ie_len);
lifetime->ie_type = WLAN_EID_TIMEOUT_INTERVAL;
lifetime->ie_len = sizeof(struct wpa_tdls_timeoutie) - 2;
lifetime->interval_type = WLAN_TIMEOUT_KEY_LIFETIME;
WPA_PUT_LE32(lifetime->value, tsecs); /* dot11RSNAConfigSMKLifetime */
os_memcpy(pos, ie, ie_len);
return pos + ie_len;
}
/**
* wpa_tdls_start - Initiate TDLS handshake (send TPK Handshake Message 1)
* @sm: Pointer to WPA state machine data from wpa_sm_init()
* @peer: MAC address of the peer STA
* Returns: 0 on success, or -1 on failure
*
* Send TPK Handshake Message 1 info to driver to start TDLS
* handshake with the peer.
*/
int wpa_tdls_start(struct wpa_sm *sm, const u8 *addr)
{
struct wpa_tdls_peer *peer;
/* Find existing entry and if found, use that instead of adding
* a new one */
for (peer = sm->tdls; peer; peer = peer->next) {
if (os_memcmp(peer->addr, addr, ETH_ALEN) == 0)
break;
}
if (peer == NULL) {
wpa_printf(MSG_INFO, "TDLS: No matching entry found for "
"peer, creating one for " MACSTR, MAC2STR(addr));
peer = os_malloc(sizeof(*peer));
if (peer == NULL)
return -1;
os_memset(peer, 0, sizeof(*peer));
os_memcpy(peer->addr, addr, ETH_ALEN);
peer->next = sm->tdls;
sm->tdls = peer;
}
peer->initiator = 1;
return wpa_tdls_send_tpk_m1(sm, peer);
}
/**
* wpa_supplicant_rx_tdls - Receive TDLS data frame
*
* This function is called to receive TDLS (ethertype = 0x890d) data frames.
*/
static void wpa_supplicant_rx_tdls(void *ctx, const u8 *src_addr,
const u8 *buf, size_t len)
{
struct wpa_sm *sm = ctx;
struct wpa_tdls_frame *tf;
wpa_hexdump(MSG_DEBUG, "TDLS: Received Data frame encapsulation",
buf, len);
if (os_memcmp(src_addr, sm->own_addr, ETH_ALEN) == 0) {
wpa_printf(MSG_DEBUG, "TDLS: Discard copy of own message");
return;
}
if (len < sizeof(*tf)) {
wpa_printf(MSG_INFO, "TDLS: Drop too short frame");
return;
}
/* Check to make sure its a valid encapsulated TDLS frame */
tf = (struct wpa_tdls_frame *) buf;
if (tf->payloadtype != 2 /* TDLS_RFTYPE */ ||
tf->category != WLAN_ACTION_TDLS) {
wpa_printf(MSG_INFO, "TDLS: Invalid frame - payloadtype=%u "
"category=%u action=%u",
tf->payloadtype, tf->category, tf->action);
return;
}
switch (tf->action) {
case WLAN_TDLS_SETUP_REQUEST:
wpa_tdls_process_tpk_m1(sm, src_addr, buf, len);
break;
case WLAN_TDLS_SETUP_RESPONSE:
wpa_tdls_process_tpk_m2(sm, src_addr, buf, len);
break;
case WLAN_TDLS_SETUP_CONFIRM:
wpa_tdls_process_tpk_m3(sm, src_addr, buf, len);
break;
case WLAN_TDLS_TEARDOWN:
wpa_tdls_recv_teardown(sm, src_addr, buf, len);
break;
default:
/* Kernel code will process remaining frames */
wpa_printf(MSG_DEBUG, "TDLS: Ignore TDLS frame action code %u",
tf->action);
break;
}
}
/**
* wpa_tdls_init - Initialize driver interface parameters for TDLS
* @wpa_s: Pointer to wpa_supplicant data
* Returns: 0 on success, -1 on failure
*
* This function is called to initialize driver interface parameters for TDLS.
* wpa_drv_init() must have been called before this function to initialize the
* driver interface.
*/
int wpa_tdls_init(struct wpa_sm *sm)
{
if (sm == NULL)
return -1;
sm->l2_tdls = l2_packet_init(sm->ifname, sm->own_addr,
ETH_P_80211_ENCAP, wpa_supplicant_rx_tdls,
sm, 0);
if (sm->l2_tdls == NULL) {
wpa_printf(MSG_ERROR, "TDLS: Failed to open l2_packet "
"connection");
return -1;
}
return 0;
}
static void wpa_tdls_remove_peers(struct wpa_sm *sm)
{
struct wpa_tdls_peer *peer, *tmp;
peer = sm->tdls;
sm->tdls = NULL;
while (peer) {
int res;
tmp = peer->next;
res = wpa_sm_tdls_oper(sm, TDLS_DISABLE_LINK, peer->addr);
wpa_printf(MSG_DEBUG, "TDLS: Remove peer " MACSTR " (res=%d)",
MAC2STR(peer->addr), res);
wpa_tdls_peer_free(sm, peer);
os_free(peer);
peer = tmp;
}
}
/**
* wpa_tdls_deinit - Deinitialize driver interface parameters for TDLS
*
* This function is called to recover driver interface parameters for TDLS
* and frees resources allocated for it.
*/
void wpa_tdls_deinit(struct wpa_sm *sm)
{
if (sm == NULL)
return;
if (sm->l2_tdls)
l2_packet_deinit(sm->l2_tdls);
sm->l2_tdls = NULL;
wpa_tdls_remove_peers(sm);
}
void wpa_tdls_assoc(struct wpa_sm *sm)
{
wpa_printf(MSG_DEBUG, "TDLS: Remove peers on association");
wpa_tdls_remove_peers(sm);
}
void wpa_tdls_disassoc(struct wpa_sm *sm)
{
wpa_printf(MSG_DEBUG, "TDLS: Remove peers on disassociation");
wpa_tdls_remove_peers(sm);
}