/**
* peerkey_verify_eapol_key_mic - Verify PeerKey MIC
* @sm: Pointer to WPA state machine data from wpa_sm_init()
* @peerkey: Pointer to the PeerKey data for the peer
* @key: Pointer to the EAPOL-Key frame header
* @ver: Version bits from EAPOL-Key Key Info
* @buf: Pointer to the beginning of EAPOL-Key frame
* @len: Length of the EAPOL-Key frame
* Returns: 0 on success, -1 on failure
*/
int peerkey_verify_eapol_key_mic(struct wpa_sm *sm,
struct wpa_peerkey *peerkey,
struct wpa_eapol_key *key, u16 ver,
const u8 *buf, size_t len)
{
u8 mic[16];
int ok = 0;
if (peerkey->initiator && !peerkey->stk_set) {
wpa_pmk_to_ptk(peerkey->smk, PMK_LEN, "Peer key expansion",
sm->own_addr, peerkey->addr,
peerkey->inonce, key->key_nonce,
(u8 *) &peerkey->stk, sizeof(peerkey->stk),
peerkey->use_sha256);
peerkey->stk_set = 1;
}
os_memcpy(mic, key->key_mic, 16);
if (peerkey->tstk_set) {
os_memset(key->key_mic, 0, 16);
wpa_eapol_key_mic(peerkey->tstk.kck, ver, buf, len,
key->key_mic);
if (os_memcmp(mic, key->key_mic, 16) != 0) {
wpa_printf(MSG_WARNING, "RSN: Invalid EAPOL-Key MIC "
"when using TSTK - ignoring TSTK");
} else {
ok = 1;
peerkey->tstk_set = 0;
peerkey->stk_set = 1;
os_memcpy(&peerkey->stk, &peerkey->tstk,
sizeof(peerkey->stk));
}
}
if (!ok && peerkey->stk_set) {
os_memset(key->key_mic, 0, 16);
wpa_eapol_key_mic(peerkey->stk.kck, ver, buf, len,
key->key_mic);
if (os_memcmp(mic, key->key_mic, 16) != 0) {
wpa_printf(MSG_WARNING, "RSN: Invalid EAPOL-Key MIC "
"- dropping packet");
return -1;
}
ok = 1;
}
if (!ok) {
wpa_printf(MSG_WARNING, "RSN: Could not verify EAPOL-Key MIC "
"- dropping packet");
return -1;
}
os_memcpy(peerkey->replay_counter, key->replay_counter,
WPA_REPLAY_COUNTER_LEN);
peerkey->replay_counter_set = 1;
return 0;
}
static int wpa_supplicant_verify_eapol_key_mic(struct wpa_sm *sm,
struct wpa_eapol_key *key,
u16 ver,
const u8 *buf, size_t len)
{
u8 mic[16];
int ok = 0;
os_memcpy(mic, key->key_mic, 16);
if (sm->tptk_set)
{
os_memset(key->key_mic, 0, 16);
wpa_eapol_key_mic(sm->tptk.kck, ver, buf, len, key->key_mic);
if (os_memcmp(mic, key->key_mic, 16) != 0)
{
lwip_log("WPA: Invalid EAPOL-Key MIC when using TPTK - ignoring TPTK\n");
}
else
{
ok = 1;
sm->tptk_set = 0;
sm->ptk_set = 1;
os_memcpy(&sm->ptk, &sm->tptk, sizeof(sm->ptk));
}
}
if (!ok && sm->ptk_set)
{
os_memset(key->key_mic, 0, 16);
wpa_eapol_key_mic(sm->ptk.kck, ver, buf, len, key->key_mic);
if (os_memcmp(mic, key->key_mic, 16) != 0)
{
lwip_log("WPA: Invalid EAPOL-Key MIC - dropping packet\n");
return -1;
}
ok = 1;
}
if (!ok)
{
lwip_log("WPA: Could not verify EAPOL-Key MIC - dropping packet\n");
return -1;
}
os_memcpy(sm->rx_replay_counter, key->replay_counter, WPA_REPLAY_COUNTER_LEN);
sm->rx_replay_counter_set = 1;
return 0;
}
static int check_mic(const u8 *kck, int ver, const u8 *data, size_t len)
{
u8 *buf;
int ret = -1;
struct ieee802_1x_hdr *hdr;
struct wpa_eapol_key *key;
u8 rx_mic[16];
buf = os_malloc(len);
if (buf == NULL)
return -1;
os_memcpy(buf, data, len);
hdr = (struct ieee802_1x_hdr *) buf;
key = (struct wpa_eapol_key *) (hdr + 1);
os_memcpy(rx_mic, key->key_mic, 16);
os_memset(key->key_mic, 0, 16);
if (wpa_eapol_key_mic(kck, ver, buf, len, key->key_mic) == 0 &&
os_memcmp(rx_mic, key->key_mic, 16) == 0)
ret = 0;
os_free(buf);
return ret;
}
/**
* wpa_eapol_key_send - Send WPA/RSN EAPOL-Key message
* @sm: Pointer to WPA state machine data from wpa_sm_init()
* @kck: Key Confirmation Key (KCK, part of PTK)
* @ver: Version field from Key Info
* @dest: Destination address for the frame
* @proto: Ethertype (usually ETH_P_EAPOL)
* @msg: EAPOL-Key message
* @msg_len: Length of message
* @key_mic: Pointer to the buffer to which the EAPOL-Key MIC is written
*/
void wpa_eapol_key_send(struct wpa_sm *sm, const u8 *kck,
int ver, const u8 *dest, u16 proto,
u8 *msg, size_t msg_len, u8 *key_mic)
{
if (is_zero_ether_addr(dest) && is_zero_ether_addr(sm->bssid)) {
/*
* Association event was not yet received; try to fetch
* BSSID from the driver.
*/
if (wpa_sm_get_bssid(sm, sm->bssid) < 0) {
wpa_printf(MSG_DEBUG, "WPA: Failed to read BSSID for "
"EAPOL-Key destination address");
} else {
dest = sm->bssid;
wpa_printf(MSG_DEBUG, "WPA: Use BSSID (" MACSTR
") as the destination for EAPOL-Key",
MAC2STR(dest));
}
}
if (key_mic &&
wpa_eapol_key_mic(kck, ver, msg, msg_len, key_mic)) {
wpa_printf(MSG_ERROR, "WPA: Failed to generate EAPOL-Key "
"version %d MIC", ver);
goto out;
}
wpa_hexdump(MSG_MSGDUMP, "WPA: TX EAPOL-Key", msg, msg_len);
wpa_sm_ether_send(sm, dest, proto, msg, msg_len);
eapol_sm_notify_tx_eapol_key(sm->eapol);
out:
os_free(msg);
}
static void wpa_eapol_key_send(struct wpa_sm *sm, const u8 *kck,
int ver, const u8 *dest, u16 proto,
u8 *msg, size_t msg_len, u8 *key_mic)
{
#if 0
if (os_memcmp(dest, "\x00\x00\x00\x00\x00\x00", ETH_ALEN) == 0 &&
os_memcmp(sm->bssid, "\x00\x00\x00\x00\x00\x00", ETH_ALEN) == 0) {
/*
* Association event was not yet received; try to fetch
* BSSID from the driver.
*/
if (wpa_sm_get_bssid(sm, sm->bssid) < 0) {
lwip_log("WPA: Failed to read BSSID for EAPOL-Key destination address\n");
} else {
dest = sm->bssid;
lwip_log("WPA: Use BSSID (" MACSTR ") as the destination for EAPOL-Key\n",
MAC2STR(dest));
}
}
#endif
//generate MIC.
if (key_mic)
{
wpa_eapol_key_mic(kck, ver, msg, msg_len, key_mic);
}
wpa_ether_send(dest, proto, msg, msg_len);
os_free(msg);
}
