WPA: Add PTKSA cache to wpa_supplicant for PASN

PASN requires to store the PTK derived during PASN authentication
so it can later be used for secure LTF etc. This is also true
for a PTK derived during regular connection.

Add an instance of a PTKSA cache for each wpa_supplicant
interface when PASN is enabled in build configuration.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>

src/rsn_supp/wpa.c

@@ -949,6 +949,9 @@ static int wpa_supplicant_install_ptk(struct wpa_sm *sm,
 		return -1;
 	}
 
+	wpa_sm_store_ptk(sm, sm->bssid, sm->pairwise_cipher,
+			 sm->dot11RSNAConfigPMKLifetime, &sm->ptk);
+
 	/* TK is not needed anymore in supplicant */
 	os_memset(sm->ptk.tk, 0, WPA_TK_MAX_LEN);
 	sm->ptk.tk_len = 0;
@@ -4916,6 +4919,9 @@ int fils_process_assoc_resp(struct wpa_sm *sm, const u8 *resp, size_t len)
 		goto fail;
 	}
 
+	wpa_sm_store_ptk(sm, sm->bssid, sm->pairwise_cipher,
+			 sm->dot11RSNAConfigPMKLifetime, &sm->ptk);
+
 	/* TODO: TK could be cleared after auth frame exchange now that driver
 	 * takes care of association frame encryption/decryption. */
 	/* TK is not needed anymore in supplicant */

src/rsn_supp/wpa.h

@@ -87,6 +87,8 @@ struct wpa_sm_ctx {
 			    const u8 *pkt, size_t pkt_len);
 	int (*channel_info)(void *ctx, struct wpa_channel_info *ci);
 	void (*transition_disable)(void *ctx, u8 bitmap);
+	void (*store_ptk)(void *ctx, u8 *addr, int cipher,
+			  u32 life_time, const struct wpa_ptk *ptk);
 };
 
 

src/rsn_supp/wpa_ft.c

@@ -449,6 +449,8 @@ static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
 		return -1;
 	}
 
+	wpa_sm_store_ptk(sm, sm->bssid, sm->pairwise_cipher,
+			 sm->dot11RSNAConfigPMKLifetime, &sm->ptk);
 	return 0;
 }
 

src/rsn_supp/wpa_i.h

@@ -447,6 +447,14 @@ static inline void wpa_sm_transition_disable(struct wpa_sm *sm, u8 bitmap)
 		sm->ctx->transition_disable(sm->ctx->ctx, bitmap);
 }
 
+static inline void wpa_sm_store_ptk(struct wpa_sm *sm,
+				    u8 *addr, int cipher,
+				    u32 life_time, struct wpa_ptk *ptk)
+{
+	if (sm->ctx->store_ptk)
+		sm->ctx->store_ptk(sm->ctx->ctx, addr, cipher, life_time,
+				   ptk);
+}
 
 int wpa_eapol_key_send(struct wpa_sm *sm, struct wpa_ptk *ptk,
 		       int ver, const u8 *dest, u16 proto,

wpa_supplicant/Android.mk

@@ -373,10 +373,12 @@ endif
 
 ifdef CONFIG_PASN
 L_CFLAGS += -DCONFIG_PASN
+L_CFLAGS += -DCONFIG_PTKSA_CACHE
 NEED_HMAC_SHA256_KDF=y
 NEED_HMAC_SHA384_KDF=y
 NEED_SHA256=y
 NEED_SHA384=y
+OBJS += src/common/ptksa_cache.c
 endif
 
 ifdef CONFIG_HS20

wpa_supplicant/Makefile

@@ -392,10 +392,12 @@ endif
 
 ifdef CONFIG_PASN
 CFLAGS += -DCONFIG_PASN
+CFLAGS += -DCONFIG_PTKSA_CACHE
 NEED_HMAC_SHA256_KDF=y
 NEED_HMAC_SHA384_KDF=y
 NEED_SHA256=y
 NEED_SHA384=y
+OBJS += ../src/common/ptksa_cache.o
 endif
 
 ifdef CONFIG_HS20

wpa_supplicant/ctrl_iface.c

@@ -22,6 +22,7 @@
 #ifdef CONFIG_DPP
 #include "common/dpp.h"
 #endif /* CONFIG_DPP */
+#include "common/ptksa_cache.h"
 #include "crypto/tls.h"
 #include "ap/hostapd.h"
 #include "eap_peer/eap.h"
@@ -8431,6 +8432,7 @@ static void wpa_supplicant_ctrl_iface_flush(struct wpa_supplicant *wpa_s)
 	wpa_s->conf->auto_interworking = 0;
 	wpa_s->conf->okc = 0;
 
+	ptksa_cache_flush(wpa_s->ptksa, NULL, WPA_CIPHER_NONE);
 	wpa_sm_pmksa_cache_flush(wpa_s->wpa, NULL);
 	rsn_preauth_deinit(wpa_s->wpa);
 
@@ -10108,6 +10110,7 @@ static int wpas_ctrl_iface_pmksa(struct wpa_supplicant *wpa_s,
 
 static void wpas_ctrl_iface_pmksa_flush(struct wpa_supplicant *wpa_s)
 {
+	ptksa_cache_flush(wpa_s->ptksa, NULL, WPA_CIPHER_NONE);
 	wpa_sm_pmksa_cache_flush(wpa_s->wpa, NULL);
 #ifdef CONFIG_AP
 	wpas_ap_pmksa_cache_flush(wpa_s);

wpa_supplicant/events.c

@@ -30,6 +30,7 @@
 #include "common/ieee802_11_common.h"
 #include "common/gas_server.h"
 #include "common/dpp.h"
+#include "common/ptksa_cache.h"
 #include "crypto/random.h"
 #include "blacklist.h"
 #include "wpas_glue.h"
@@ -3482,6 +3483,8 @@ static void wpa_supplicant_event_disassoc_finish(struct wpa_supplicant *wpa_s,
 	if (wpa_s->wpa_state >= WPA_AUTHENTICATING)
 		wpas_connection_failed(wpa_s, bssid);
 	wpa_sm_notify_disassoc(wpa_s->wpa);
+	ptksa_cache_flush(wpa_s->ptksa, wpa_s->bssid, WPA_CIPHER_NONE);
+
 	if (locally_generated)
 		wpa_s->disconnect_reason = -reason_code;
 	else

wpa_supplicant/wpa_supplicant.c

@@ -41,6 +41,7 @@
 #include "common/hw_features_common.h"
 #include "common/gas_server.h"
 #include "common/dpp.h"
+#include "common/ptksa_cache.h"
 #include "p2p/p2p.h"
 #include "fst/fst.h"
 #include "blacklist.h"
@@ -573,6 +574,8 @@ static void wpa_supplicant_cleanup(struct wpa_supplicant *wpa_s)
 
 	wmm_ac_clear_saved_tspecs(wpa_s);
 	pmksa_candidate_free(wpa_s->wpa);
+	ptksa_cache_deinit(wpa_s->ptksa);
+	wpa_s->ptksa = NULL;
 	wpa_sm_deinit(wpa_s->wpa);
 	wpa_s->wpa = NULL;
 	wpa_blacklist_clear(wpa_s);

wpa_supplicant/wpa_supplicant_i.h

@@ -639,6 +639,8 @@ struct wpa_supplicant {
 	int interface_removed; /* whether the network interface has been
 				* removed */
 	struct wpa_sm *wpa;
+	struct ptksa_cache *ptksa;
+
 	struct eapol_sm *eapol;
 
 	struct ctrl_iface_priv *ctrl_iface;

wpa_supplicant/wpas_glue.c

@@ -16,6 +16,7 @@
 #include "config.h"
 #include "l2_packet/l2_packet.h"
 #include "common/wpa_common.h"
+#include "common/ptksa_cache.h"
 #include "wpa_supplicant_i.h"
 #include "driver_i.h"
 #include "rsn_supp/pmksa_cache.h"
@@ -1341,6 +1342,15 @@ static void wpa_supplicant_transition_disable(void *_wpa_s, u8 bitmap)
 #endif /* CONFIG_NO_CONFIG_WRITE */
 }
 
+
+static void wpa_supplicant_store_ptk(void *ctx, u8 *addr, int cipher,
+				     u32 life_time, const struct wpa_ptk *ptk)
+{
+	struct wpa_supplicant *wpa_s = ctx;
+
+	ptksa_cache_add(wpa_s->ptksa, addr, cipher, life_time, ptk);
+}
+
 #endif /* CONFIG_NO_WPA */
 
 
@@ -1348,9 +1358,20 @@ int wpa_supplicant_init_wpa(struct wpa_supplicant *wpa_s)
 {
 #ifndef CONFIG_NO_WPA
 	struct wpa_sm_ctx *ctx;
+
+	wpa_s->ptksa = ptksa_cache_init();
+	if (!wpa_s->ptksa) {
+		wpa_printf(MSG_ERROR, "Failed to allocate PTKSA");
+		return -1;
+	}
+
 	ctx = os_zalloc(sizeof(*ctx));
 	if (ctx == NULL) {
 		wpa_printf(MSG_ERROR, "Failed to allocate WPA context.");
+
+		ptksa_cache_deinit(wpa_s->ptksa);
+		wpa_s->ptksa = NULL;
+
 		return -1;
 	}
 
@@ -1394,12 +1415,15 @@ int wpa_supplicant_init_wpa(struct wpa_supplicant *wpa_s)
 	ctx->fils_hlp_rx = wpa_supplicant_fils_hlp_rx;
 	ctx->channel_info = wpa_supplicant_channel_info;
 	ctx->transition_disable = wpa_supplicant_transition_disable;
+	ctx->store_ptk = wpa_supplicant_store_ptk;
 
 	wpa_s->wpa = wpa_sm_init(ctx);
 	if (wpa_s->wpa == NULL) {
-		wpa_printf(MSG_ERROR, "Failed to initialize WPA state "
-			   "machine");
+		wpa_printf(MSG_ERROR,
+			   "Failed to initialize WPA state machine");
 		os_free(ctx);
+		ptksa_cache_deinit(wpa_s->ptksa);
+		wpa_s->ptksa = NULL;
 		return -1;
 	}
 #endif /* CONFIG_NO_WPA */