peerkey.c

最新的Host AP 新添加了许多pcmcia 的驱动

	/* RSN: msg 2/4 should contain SMKID for the selected SMK and RSN IE
	 * from the peer. It may also include Lifetime KDE. */
	keydata = (const u8 *) (key + 1);
	len = WPA_GET_BE16(key->key_data_length);
	wpa_hexdump(MSG_DEBUG, "RSN: msg 2/4 key data", keydata, len);
	if (wpa_supplicant_parse_ies(keydata, len, &kde) < 0 ||
	    kde.pmkid == NULL || kde.rsn_ie == NULL) {
		wpa_printf(MSG_DEBUG, "RSN: No SMKID or RSN IE in STK 2/4");
		return;
	}

	if (os_memcmp(kde.pmkid, peerkey->smkid, PMKID_LEN) != 0) {
		wpa_hexdump(MSG_DEBUG, "RSN: Unknown SMKID in STK 2/4",
			    kde.pmkid, PMKID_LEN);
		return;
	}

	if (kde.rsn_ie_len != peerkey->rsnie_p_len ||
	    os_memcmp(kde.rsn_ie, peerkey->rsnie_p, kde.rsn_ie_len) != 0) {
		wpa_printf(MSG_INFO, "RSN: Peer RSN IE in SMK and STK "
			   "handshakes did not match");
		wpa_hexdump(MSG_DEBUG, "RSN: Peer RSN IE in SMK handshake",
			    peerkey->rsnie_p, peerkey->rsnie_p_len);
		wpa_hexdump(MSG_DEBUG, "RSN: Peer RSN IE in STK handshake",
			    kde.rsn_ie, kde.rsn_ie_len);
		return;
	}

	wpa_supplicant_update_smk_lifetime(sm, peerkey, &kde);

	wpa_supplicant_send_stk_3_of_4(sm, peerkey);
	os_memcpy(peerkey->pnonce, key->key_nonce, WPA_NONCE_LEN);
}


static void wpa_supplicant_process_stk_3_of_4(struct wpa_sm *sm,
					      struct wpa_peerkey *peerkey,
					      const struct wpa_eapol_key *key,
					      u16 ver)
{
	struct wpa_eapol_ie_parse kde;
	const u8 *keydata;
	size_t len, key_len;
	const u8 *_key;
	u8 key_buf[32], rsc[6];

	wpa_printf(MSG_DEBUG, "RSN: RX message 3 of STK 4-Way Handshake from "
		   MACSTR " (ver=%d)", MAC2STR(peerkey->addr), ver);

	os_memset(&kde, 0, sizeof(kde));

	/* RSN: msg 3/4 should contain Initiator RSN IE. It may also include
	 * Lifetime KDE. */
	keydata = (const u8 *) (key + 1);
	len = WPA_GET_BE16(key->key_data_length);
	wpa_hexdump(MSG_DEBUG, "RSN: msg 3/4 key data", keydata, len);
	if (wpa_supplicant_parse_ies(keydata, len, &kde) < 0) {
		wpa_printf(MSG_DEBUG, "RSN: Failed to parse key data in "
			   "STK 3/4");
		return;
	}

	if (kde.rsn_ie_len != peerkey->rsnie_i_len ||
	    os_memcmp(kde.rsn_ie, peerkey->rsnie_i, kde.rsn_ie_len) != 0) {
		wpa_printf(MSG_INFO, "RSN: Initiator RSN IE in SMK and STK "
			   "handshakes did not match");
		wpa_hexdump(MSG_DEBUG, "RSN: Initiator RSN IE in SMK "
			    "handshake",
			    peerkey->rsnie_i, peerkey->rsnie_i_len);
		wpa_hexdump(MSG_DEBUG, "RSN: Initiator RSN IE in STK "
			    "handshake",
			    kde.rsn_ie, kde.rsn_ie_len);
		return;
	}

	if (os_memcmp(peerkey->inonce, key->key_nonce, WPA_NONCE_LEN) != 0) {
		wpa_printf(MSG_WARNING, "RSN: INonce from message 1 of STK "
			   "4-Way Handshake differs from 3 of STK 4-Way "
			   "Handshake - drop packet (src=" MACSTR ")",
			   MAC2STR(peerkey->addr));
		return;
	}

	wpa_supplicant_update_smk_lifetime(sm, peerkey, &kde);

	if (wpa_supplicant_send_4_of_4(sm, peerkey->addr, key, ver,
				       WPA_GET_BE16(key->key_info),
				       NULL, 0, &peerkey->stk))
		return;

	_key = (u8 *) peerkey->stk.tk1;
	if (peerkey->cipher == WPA_CIPHER_TKIP) {
		/* Swap Tx/Rx keys for Michael MIC */
		os_memcpy(key_buf, _key, 16);
		os_memcpy(key_buf + 16, peerkey->stk.u.auth.rx_mic_key, 8);
		os_memcpy(key_buf + 24, peerkey->stk.u.auth.tx_mic_key, 8);
		_key = key_buf;
		key_len = 32;
	} else
		key_len = 16;

	os_memset(rsc, 0, 6);
	if (wpa_sm_set_key(sm, peerkey->cipher, peerkey->addr, 0, 1,
			   rsc, sizeof(rsc), _key, key_len) < 0) {
		wpa_printf(MSG_WARNING, "RSN: Failed to set STK to the "
			   "driver.");
		return;
	}
}


static void wpa_supplicant_process_stk_4_of_4(struct wpa_sm *sm,
					      struct wpa_peerkey *peerkey,
					      const struct wpa_eapol_key *key,
					      u16 ver)
{
	u8 rsc[6];

	wpa_printf(MSG_DEBUG, "RSN: RX message 4 of STK 4-Way Handshake from "
		   MACSTR " (ver=%d)", MAC2STR(peerkey->addr), ver);

	os_memset(rsc, 0, 6);
	if (wpa_sm_set_key(sm, peerkey->cipher, peerkey->addr, 0, 1,
			   rsc, sizeof(rsc), (u8 *) peerkey->stk.tk1,
			   peerkey->cipher == WPA_CIPHER_TKIP ? 32 : 16) < 0) {
		wpa_printf(MSG_WARNING, "RSN: Failed to set STK to the "
			   "driver.");
		return;
	}
}


/**
 * 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;
}


/**
 * wpa_sm_stkstart - Send EAPOL-Key Request for STK handshake (STK M1)
 * @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 an EAPOL-Key Request to the current authenticator to start STK
 * handshake with the peer.
 */
int wpa_sm_stkstart(struct wpa_sm *sm, const u8 *peer)
{
	size_t rlen, kde_len;
	struct wpa_eapol_key *req;
	int key_info, ver;
	u8 bssid[ETH_ALEN], *rbuf, *pos, *count_pos;
	u16 count;
	struct rsn_ie_hdr *hdr;
	struct wpa_peerkey *peerkey;
	struct wpa_ie_data ie;

	if (sm->proto != WPA_PROTO_RSN || !sm->ptk_set || !sm->peerkey_enabled)
		return -1;

	if (sm->ap_rsn_ie &&
	    wpa_parse_wpa_ie_rsn(sm->ap_rsn_ie, sm->ap_rsn_ie_len, &ie) == 0 &&
	    !(ie.capabilities & WPA_CAPABILITY_PEERKEY_ENABLED)) {
		wpa_printf(MSG_DEBUG, "RSN: Current AP does not support STK");
		return -1;
	}

	if (sm->pairwise_cipher == WPA_CIPHER_CCMP)
		ver = WPA_KEY_INFO_TYPE_HMAC_SHA1_AES;
	else
		ver = WPA_KEY_INFO_TYPE_HMAC_MD5_RC4;

	if (wpa_sm_get_bssid(sm, bssid) < 0) {
		wpa_printf(MSG_WARNING, "Failed to read BSSID for EAPOL-Key "
			   "SMK M1");
		return -1;
	}

	/* TODO: find existing entry and if found, use that instead of adding
	 * a new one */
	peerkey = os_zalloc(sizeof(*peerkey));
	if (peerkey == NULL)
		return -1;
	peerkey->initiator = 1;
	os_memcpy(peerkey->addr, peer, ETH_ALEN);
#ifdef CONFIG_IEEE80211W
	if (wpa_key_mgmt_sha256(sm->key_mgmt))
		peerkey->use_sha256 = 1;
#endif /* CONFIG_IEEE80211W */

	/* SMK M1:
	 * EAPOL-Key(S=1, M=1, A=0, I=0, K=0, SM=1, KeyRSC=0, Nonce=INonce,
	 *           MIC=MIC, DataKDs=(RSNIE_I, MAC_P KDE))
	 */

	hdr = (struct rsn_ie_hdr *) peerkey->rsnie_i;
	hdr->elem_id = WLAN_EID_RSN;
	WPA_PUT_LE16(hdr->version, RSN_VERSION);
	pos = (u8 *) (hdr + 1);
	/* Group Suite can be anything for SMK RSN IE; receiver will just
	 * ignore it. */
	RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
	pos += RSN_SELECTOR_LEN;
	count_pos = pos;
	pos += 2;

	count = 0;
	if (sm->allowed_pairwise_cipher & WPA_CIPHER_CCMP) {
		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
		pos += RSN_SELECTOR_LEN;
		count++;
	}
	if (sm->allowed_pairwise_cipher & WPA_CIPHER_TKIP) {
		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
		pos += RSN_SELECTOR_LEN;
		count++;
	}
	WPA_PUT_LE16(count_pos, count);

	hdr->len = (pos - peerkey->rsnie_i) - 2;
	peerkey->rsnie_i_len = pos - peerkey->rsnie_i;
	wpa_hexdump(MSG_DEBUG, "WPA: RSN IE for SMK handshake",
		    peerkey->rsnie_i, peerkey->rsnie_i_len);

	kde_len = peerkey->rsnie_i_len + 2 + RSN_SELECTOR_LEN + ETH_ALEN;

	rbuf = wpa_sm_alloc_eapol(sm, IEEE802_1X_TYPE_EAPOL_KEY, NULL,
				  sizeof(*req) + kde_len, &rlen,
				  (void *) &req);
	if (rbuf == NULL) {
		wpa_supplicant_peerkey_free(sm, peerkey);
		return -1;
	}

	req->type = EAPOL_KEY_TYPE_RSN;
	key_info = WPA_KEY_INFO_SMK_MESSAGE | WPA_KEY_INFO_MIC |
		WPA_KEY_INFO_SECURE | WPA_KEY_INFO_REQUEST | ver;
	WPA_PUT_BE16(req->key_info, key_info);
	WPA_PUT_BE16(req->key_length, 0);
	os_memcpy(req->replay_counter, sm->request_counter,
		  WPA_REPLAY_COUNTER_LEN);
	inc_byte_array(sm->request_counter, WPA_REPLAY_COUNTER_LEN);

	if (os_get_random(peerkey->inonce, WPA_NONCE_LEN)) {
		wpa_msg(sm->ctx->ctx, MSG_WARNING,
			"WPA: Failed to get random data for INonce");
		os_free(rbuf);
		wpa_supplicant_peerkey_free(sm, peerkey);
		return -1;
	}
	os_memcpy(req->key_nonce, peerkey->inonce, WPA_NONCE_LEN);
	wpa_hexdump(MSG_DEBUG, "WPA: INonce for SMK handshake",
		    req->key_nonce, WPA_NONCE_LEN);

	WPA_PUT_BE16(req->key_data_length, (u16) kde_len);
	pos = (u8 *) (req + 1);

	/* Initiator RSN IE */
	pos = wpa_add_ie(pos, peerkey->rsnie_i, peerkey->rsnie_i_len);
	/* Peer MAC address KDE */
	wpa_add_kde(pos, RSN_KEY_DATA_MAC_ADDR, peer, ETH_ALEN);

	wpa_printf(MSG_INFO, "RSN: Sending EAPOL-Key SMK M1 Request (peer "
		   MACSTR ")", MAC2STR(peer));
	wpa_eapol_key_send(sm, sm->ptk.kck, ver, bssid, ETH_P_EAPOL,
			   rbuf, rlen, req->key_mic);

	peerkey->next = sm->peerkey;
	sm->peerkey = peerkey;

	return 0;
}


/**
 * peerkey_deinit - Free PeerKey values
 * @sm: Pointer to WPA state machine data from wpa_sm_init()
 */
void peerkey_deinit(struct wpa_sm *sm)
{
	struct wpa_peerkey *prev, *peerkey = sm->peerkey;
	while (peerkey) {
		prev = peerkey;
		peerkey = peerkey->next;
		os_free(prev);
	}
}


void peerkey_rx_eapol_4way(struct wpa_sm *sm, struct wpa_peerkey *peerkey,
			   struct wpa_eapol_key *key, u16 key_info, u16 ver)
{
	if ((key_info & (WPA_KEY_INFO_MIC | WPA_KEY_INFO_ACK)) ==
	    (WPA_KEY_INFO_MIC | WPA_KEY_INFO_ACK)) {
		/* 3/4 STK 4-Way Handshake */
		wpa_supplicant_process_stk_3_of_4(sm, peerkey, key, ver);
	} else if (key_info & WPA_KEY_INFO_ACK) {
		/* 1/4 STK 4-Way Handshake */
		wpa_supplicant_process_stk_1_of_4(sm, peerkey, key, ver);
	} else if (key_info & WPA_KEY_INFO_SECURE) {
		/* 4/4 STK 4-Way Handshake */
		wpa_supplicant_process_stk_4_of_4(sm, peerkey, key, ver);
	} else {
		/* 2/4 STK 4-Way Handshake */
		wpa_supplicant_process_stk_2_of_4(sm, peerkey, key, ver);
	}
}


void peerkey_rx_eapol_smk(struct wpa_sm *sm, const u8 *src_addr,
			  struct wpa_eapol_key *key, size_t extra_len,
			  u16 key_info, u16 ver)
{
	if (key_info & WPA_KEY_INFO_ERROR) {
		/* SMK Error */
		wpa_supplicant_process_smk_error(sm, src_addr, key, extra_len);
	} else if (key_info & WPA_KEY_INFO_ACK) {
		/* SMK M2 */
		wpa_supplicant_process_smk_m2(sm, src_addr, key, extra_len,
					      ver);
	} else {
		/* SMK M4 or M5 */
		wpa_supplicant_process_smk_m45(sm, src_addr, key, extra_len,
					       ver);
	}
}

#endif /* CONFIG_PEERKEY */