/**
 * pmksa_cache_auth_add - Add a PMKSA cache entry
 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init()
 * @pmk: The new pairwise master key
 * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
 * @pmkid: Calculated PMKID
 * @kck: Key confirmation key or %NULL if not yet derived
 * @kck_len: KCK length in bytes
 * @aa: Authenticator address
 * @spa: Supplicant address
 * @session_timeout: Session timeout
 * @eapol: Pointer to EAPOL state machine data
 * @akmp: WPA_KEY_MGMT_* used in key derivation
 * Returns: Pointer to the added PMKSA cache entry or %NULL on error
 *
 * This function create a PMKSA entry for a new PMK and adds it to the PMKSA
 * cache. If an old entry is already in the cache for the same Supplicant,
 * this entry will be replaced with the new entry. PMKID will be calculated
 * based on the PMK.
 */
struct rsn_pmksa_cache_entry *
pmksa_cache_auth_add(struct rsn_pmksa_cache *pmksa,
		     const u8 *pmk, size_t pmk_len, const u8 *pmkid,
		     const u8 *kck, size_t kck_len,
		     const u8 *aa, const u8 *spa, int session_timeout,
		     struct eapol_state_machine *eapol, int akmp)
{
	struct rsn_pmksa_cache_entry *entry, *pos;
	struct os_reltime now;

	if (pmk_len > PMK_LEN_MAX)
		return NULL;

	if (wpa_key_mgmt_suite_b(akmp) && !kck)
		return NULL;

	entry = os_zalloc(sizeof(*entry));
	if (entry == NULL)
		return NULL;
	os_memcpy(entry->pmk, pmk, pmk_len);
	entry->pmk_len = pmk_len;
	if (pmkid)
		os_memcpy(entry->pmkid, pmkid, PMKID_LEN);
	else if (akmp == WPA_KEY_MGMT_IEEE8021X_SUITE_B_192)
		rsn_pmkid_suite_b_192(kck, kck_len, aa, spa, entry->pmkid);
	else if (wpa_key_mgmt_suite_b(akmp))
		rsn_pmkid_suite_b(kck, kck_len, aa, spa, entry->pmkid);
	else
		rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid,
			  wpa_key_mgmt_sha256(akmp));
	os_get_reltime(&now);
	entry->expiration = now.sec;
	if (session_timeout > 0)
		entry->expiration += session_timeout;
	else
		entry->expiration += dot11RSNAConfigPMKLifetime;
	entry->akmp = akmp;
	os_memcpy(entry->spa, spa, ETH_ALEN);
	pmksa_cache_from_eapol_data(entry, eapol);

	/* Replace an old entry for the same STA (if found) with the new entry
	 */
	pos = pmksa_cache_auth_get(pmksa, spa, NULL);
	if (pos)
		pmksa_cache_free_entry(pmksa, pos);

	if (pmksa->pmksa_count >= pmksa_cache_max_entries && pmksa->pmksa) {
		/* Remove the oldest entry to make room for the new entry */
		wpa_printf(MSG_DEBUG, "RSN: removed the oldest PMKSA cache "
			   "entry (for " MACSTR ") to make room for new one",
			   MAC2STR(pmksa->pmksa->spa));
		pmksa_cache_free_entry(pmksa, pmksa->pmksa);
	}

	pmksa_cache_link_entry(pmksa, entry);

	return entry;
}
/**
 * pmksa_cache_auth_create_entry - Create a PMKSA cache entry
 * @pmk: The new pairwise master key
 * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
 * @pmkid: Calculated PMKID
 * @kck: Key confirmation key or %NULL if not yet derived
 * @kck_len: KCK length in bytes
 * @aa: Authenticator address
 * @spa: Supplicant address
 * @session_timeout: Session timeout
 * @eapol: Pointer to EAPOL state machine data
 * @akmp: WPA_KEY_MGMT_* used in key derivation
 * Returns: Pointer to the added PMKSA cache entry or %NULL on error
 *
 * This function creates a PMKSA entry.
 */
struct rsn_pmksa_cache_entry *
pmksa_cache_auth_create_entry(const u8 *pmk, size_t pmk_len, const u8 *pmkid,
			      const u8 *kck, size_t kck_len, const u8 *aa,
			      const u8 *spa, int session_timeout,
			      struct eapol_state_machine *eapol, int akmp)
{
	struct rsn_pmksa_cache_entry *entry;
	struct os_reltime now;

	if (pmk_len > PMK_LEN_MAX)
		return NULL;

	if (wpa_key_mgmt_suite_b(akmp) && !kck)
		return NULL;

	entry = os_zalloc(sizeof(*entry));
	if (entry == NULL)
		return NULL;
	os_memcpy(entry->pmk, pmk, pmk_len);
	entry->pmk_len = pmk_len;
	if (pmkid)
		os_memcpy(entry->pmkid, pmkid, PMKID_LEN);
	else if (akmp == WPA_KEY_MGMT_IEEE8021X_SUITE_B_192)
		rsn_pmkid_suite_b_192(kck, kck_len, aa, spa, entry->pmkid);
	else if (wpa_key_mgmt_suite_b(akmp))
		rsn_pmkid_suite_b(kck, kck_len, aa, spa, entry->pmkid);
	else
		rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid, akmp);
	os_get_reltime(&now);
	entry->expiration = now.sec;
	if (session_timeout > 0)
		entry->expiration += session_timeout;
	else
		entry->expiration += dot11RSNAConfigPMKLifetime;
	entry->akmp = akmp;
	os_memcpy(entry->spa, spa, ETH_ALEN);
	pmksa_cache_from_eapol_data(entry, eapol);

	return entry;
}
Esempio n. 3
0
/**
 * pmksa_cache_add - Add a PMKSA cache entry
 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
 * @pmk: The new pairwise master key
 * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
 * @pmkid: Calculated PMKID
 * @kck: Key confirmation key or %NULL if not yet derived
 * @kck_len: KCK length in bytes
 * @aa: Authenticator address
 * @spa: Supplicant address
 * @network_ctx: Network configuration context for this PMK
 * @akmp: WPA_KEY_MGMT_* used in key derivation
 * Returns: Pointer to the added PMKSA cache entry or %NULL on error
 *
 * This function create a PMKSA entry for a new PMK and adds it to the PMKSA
 * cache. If an old entry is already in the cache for the same Authenticator,
 * this entry will be replaced with the new entry. PMKID will be calculated
 * based on the PMK and the driver interface is notified of the new PMKID.
 */
struct rsn_pmksa_cache_entry *
pmksa_cache_add(struct rsn_pmksa_cache *pmksa, const u8 *pmk, size_t pmk_len,
		const u8 *pmkid, const u8 *kck, size_t kck_len,
		const u8 *aa, const u8 *spa, void *network_ctx, int akmp)
{
	struct rsn_pmksa_cache_entry *entry, *pos, *prev;
	struct os_reltime now;

	if (pmk_len > PMK_LEN_MAX)
		return NULL;

	if (wpa_key_mgmt_suite_b(akmp) && !kck)
		return NULL;

	entry = os_zalloc(sizeof(*entry));
	if (entry == NULL)
		return NULL;
	os_memcpy(entry->pmk, pmk, pmk_len);
	entry->pmk_len = pmk_len;
	if (pmkid)
		os_memcpy(entry->pmkid, pmkid, PMKID_LEN);
	else if (akmp == WPA_KEY_MGMT_IEEE8021X_SUITE_B_192)
		rsn_pmkid_suite_b_192(kck, kck_len, aa, spa, entry->pmkid);
	else if (wpa_key_mgmt_suite_b(akmp))
		rsn_pmkid_suite_b(kck, kck_len, aa, spa, entry->pmkid);
	else
		rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid,
			  wpa_key_mgmt_sha256(akmp));
	os_get_reltime(&now);
	entry->expiration = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime;
	entry->reauth_time = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime *
		pmksa->sm->dot11RSNAConfigPMKReauthThreshold / 100;
	entry->akmp = akmp;
	os_memcpy(entry->aa, aa, ETH_ALEN);
	entry->network_ctx = network_ctx;

	/* Replace an old entry for the same Authenticator (if found) with the
	 * new entry */
	pos = pmksa->pmksa;
	prev = NULL;
	while (pos) {
		if (os_memcmp(aa, pos->aa, ETH_ALEN) == 0) {
			if (pos->pmk_len == pmk_len &&
			    os_memcmp_const(pos->pmk, pmk, pmk_len) == 0 &&
			    os_memcmp_const(pos->pmkid, entry->pmkid,
					    PMKID_LEN) == 0) {
				wpa_printf(MSG_DEBUG, "WPA: reusing previous "
					   "PMKSA entry");
				os_free(entry);
				return pos;
			}
			if (prev == NULL)
				pmksa->pmksa = pos->next;
			else
				prev->next = pos->next;

			/*
			 * If OKC is used, there may be other PMKSA cache
			 * entries based on the same PMK. These needs to be
			 * flushed so that a new entry can be created based on
			 * the new PMK. Only clear other entries if they have a
			 * matching PMK and this PMK has been used successfully
			 * with the current AP, i.e., if opportunistic flag has
			 * been cleared in wpa_supplicant_key_neg_complete().
			 */
			wpa_printf(MSG_DEBUG, "RSN: Replace PMKSA entry for "
				   "the current AP and any PMKSA cache entry "
				   "that was based on the old PMK");
			if (!pos->opportunistic)
				pmksa_cache_flush(pmksa, network_ctx, pos->pmk,
						  pos->pmk_len);
			pmksa_cache_free_entry(pmksa, pos, PMKSA_REPLACE);
			break;
		}
		prev = pos;
		pos = pos->next;
	}

	if (pmksa->pmksa_count >= pmksa_cache_max_entries && pmksa->pmksa) {
		/* Remove the oldest entry to make room for the new entry */
		pos = pmksa->pmksa;

		if (pos == pmksa->sm->cur_pmksa) {
			/*
			 * Never remove the current PMKSA cache entry, since
			 * it's in use, and removing it triggers a needless
			 * deauthentication.
			 */
			pos = pos->next;
			pmksa->pmksa->next = pos ? pos->next : NULL;
		} else
			pmksa->pmksa = pos->next;

		if (pos) {
			wpa_printf(MSG_DEBUG, "RSN: removed the oldest idle "
				   "PMKSA cache entry (for " MACSTR ") to "
				   "make room for new one",
				   MAC2STR(pos->aa));
			pmksa_cache_free_entry(pmksa, pos, PMKSA_FREE);
		}
	}

	/* Add the new entry; order by expiration time */
	pos = pmksa->pmksa;
	prev = NULL;
	while (pos) {
		if (pos->expiration > entry->expiration)
			break;
		prev = pos;
		pos = pos->next;
	}
	if (prev == NULL) {
		entry->next = pmksa->pmksa;
		pmksa->pmksa = entry;
		pmksa_cache_set_expiration(pmksa);
	} else {
		entry->next = prev->next;
		prev->next = entry;
	}
	pmksa->pmksa_count++;
	wpa_printf(MSG_DEBUG, "RSN: Added PMKSA cache entry for " MACSTR
		   " network_ctx=%p", MAC2STR(entry->aa), network_ctx);
	wpa_sm_add_pmkid(pmksa->sm, entry->aa, entry->pmkid);

	return entry;
}