MACsec: Support GCM-AES-256 cipher suite

Allow macsec_csindex to be configured and select the cipher suite when
the participant acts as a key server.

Signed-off-by: leiwei <quic_leiwei@quicinc.com>

hostapd/config_file.c

@@ -4661,6 +4661,16 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 			return 1;
 		}
 		bss->mka_priority = mka_priority;
+	} else if (os_strcmp(buf, "macsec_csindex") == 0) {
+		int macsec_csindex = atoi(pos);
+
+		if (macsec_csindex < 0 || macsec_csindex > 1) {
+			wpa_printf(MSG_ERROR,
+				   "Line %d: invalid macsec_csindex (%d): '%s'.",
+				   line, macsec_csindex, pos);
+			return 1;
+		}
+		bss->macsec_csindex = macsec_csindex;
 	} else if (os_strcmp(buf, "mka_cak") == 0) {
 		size_t len = os_strlen(pos);
 

hostapd/hostapd.conf

@@ -1070,6 +1070,10 @@ eapol_key_index_workaround=0
 # mka_priority (Priority of MKA Actor)
 # Range: 0..255 (default: 255)
 #
+# macsec_csindex: IEEE 802.1X/MACsec cipher suite
+# 0 = GCM-AES-128 (default)
+# 1 = GCM-AES-256 (default)
+#
 # mka_cak, mka_ckn, and mka_priority: IEEE 802.1X/MACsec pre-shared key mode
 # This allows to configure MACsec with a pre-shared key using a (CAK,CKN) pair.
 # In this mode, instances of hostapd can act as MACsec peers. The peer

src/ap/ap_config.h

@@ -848,6 +848,13 @@ struct hostapd_bss_config {
 	 */
 	int mka_priority;
 
+	/**
+	 * macsec_csindex - Cipher suite index for MACsec
+	 *
+	 * Range: 0-1 (default: 0)
+	 */
+	int macsec_csindex;
+
 	/**
 	 * mka_ckn - MKA pre-shared CKN
 	 */

src/ap/wpa_auth_kay.c

@@ -329,7 +329,9 @@ int ieee802_1x_alloc_kay_sm_hapd(struct hostapd_data *hapd,
 				  hapd->conf->macsec_replay_protect,
 				  hapd->conf->macsec_replay_window,
 				  hapd->conf->macsec_port,
-				  hapd->conf->mka_priority, hapd->conf->iface,
+				  hapd->conf->mka_priority,
+				  hapd->conf->macsec_csindex,
+				  hapd->conf->iface,
 				  hapd->own_addr);
 	/* ieee802_1x_kay_init() frees kay_ctx on failure */
 	if (!res)

src/pae/ieee802_1x_cp.c

@@ -20,7 +20,7 @@
 #define STATE_MACHINE_DATA struct ieee802_1x_cp_sm
 #define STATE_MACHINE_DEBUG_PREFIX "CP"
 
-static u64 default_cs_id = CS_ID_GCM_AES_128;
+static u64 cs_id[] = { CS_ID_GCM_AES_128, CS_ID_GCM_AES_256 };
 
 /* The variable defined in clause 12 in IEEE Std 802.1X-2010 */
 enum connect_type { PENDING, UNAUTHENTICATED, AUTHENTICATED, SECURE };
@@ -210,7 +210,6 @@ SM_STATE(CP, SECURED)
 	sm->replay_protect = sm->kay->macsec_replay_protect;
 	sm->validate_frames = sm->kay->macsec_validate;
 
-	/* NOTE: now no other than default cipher suite (AES-GCM-128) */
 	sm->current_cipher_suite = sm->cipher_suite;
 	secy_cp_control_current_cipher_suite(sm->kay, sm->current_cipher_suite);
 
@@ -473,8 +472,8 @@ struct ieee802_1x_cp_sm * ieee802_1x_cp_sm_init(struct ieee802_1x_kay *kay)
 	sm->orx = false;
 	sm->otx = false;
 
-	sm->current_cipher_suite = default_cs_id;
-	sm->cipher_suite = default_cs_id;
+	sm->current_cipher_suite = cs_id[kay->macsec_csindex];
+	sm->cipher_suite = cs_id[kay->macsec_csindex];
 	sm->cipher_offset = CONFIDENTIALITY_OFFSET_0;
 	sm->confidentiality_offset = sm->cipher_offset;
 	sm->transmit_delay = MKA_LIFE_TIME;
@@ -491,6 +490,7 @@ struct ieee802_1x_cp_sm * ieee802_1x_cp_sm_init(struct ieee802_1x_kay *kay)
 	secy_cp_control_enable_port(sm->kay, sm->controlled_port_enabled);
 	secy_cp_control_confidentiality_offset(sm->kay,
 					       sm->confidentiality_offset);
+	secy_cp_control_current_cipher_suite(sm->kay, sm->current_cipher_suite);
 
 	SM_STEP_RUN(CP);
 

src/pae/ieee802_1x_kay.c

@@ -221,8 +221,16 @@ ieee802_1x_mka_dump_dist_sak_body(struct ieee802_1x_mka_dist_sak_body *body)
 
 	wpa_printf(MSG_DEBUG, "\tKey Number............: %d",
 		   be_to_host32(body->kn));
-	/* TODO: Other than GCM-AES-128 case: MACsec Cipher Suite */
-	wpa_hexdump(MSG_DEBUG, "\tAES Key Wrap of SAK...:", body->sak, 24);
+	if (body_len == 28) {
+		wpa_hexdump(MSG_DEBUG, "\tAES Key Wrap of SAK...:",
+			    body->sak, 24);
+	} else if (body_len > CS_ID_LEN - sizeof(body->kn)) {
+		wpa_hexdump(MSG_DEBUG, "\tMACsec Cipher Suite...:",
+			    body->sak, CS_ID_LEN);
+		wpa_hexdump(MSG_DEBUG, "\tAES Key Wrap of SAK...:",
+			    body->sak + CS_ID_LEN,
+			    body_len - CS_ID_LEN - sizeof(body->kn));
+	}
 }
 
 
@@ -3456,7 +3464,8 @@ static void kay_l2_receive(void *ctx, const u8 *src_addr, const u8 *buf,
 struct ieee802_1x_kay *
 ieee802_1x_kay_init(struct ieee802_1x_kay_ctx *ctx, enum macsec_policy policy,
 		    bool macsec_replay_protect, u32 macsec_replay_window,
-		    u16 port, u8 priority, const char *ifname, const u8 *addr)
+		    u16 port, u8 priority, u32 macsec_csindex,
+		    const char *ifname, const u8 *addr)
 {
 	struct ieee802_1x_kay *kay;
 
@@ -3493,7 +3502,7 @@ ieee802_1x_kay_init(struct ieee802_1x_kay_ctx *ctx, enum macsec_policy policy,
 	kay->dist_time = 0;
 
 	kay->pn_exhaustion = PENDING_PN_EXHAUSTION;
-	kay->macsec_csindex = DEFAULT_CS_INDEX;
+	kay->macsec_csindex = macsec_csindex;
 	kay->mka_algindex = DEFAULT_MKA_ALG_INDEX;
 	kay->mka_version = MKA_VERSION_ID;
 

src/pae/ieee802_1x_kay.h

@@ -240,7 +240,8 @@ u64 mka_sci_u64(struct ieee802_1x_mka_sci *sci);
 struct ieee802_1x_kay *
 ieee802_1x_kay_init(struct ieee802_1x_kay_ctx *ctx, enum macsec_policy policy,
 		    bool macsec_replay_protect, u32 macsec_replay_window,
-		    u16 port, u8 priority, const char *ifname, const u8 *addr);
+		    u16 port, u8 priority, u32 macsec_csindex,
+		    const char *ifname, const u8 *addr);
 void ieee802_1x_kay_deinit(struct ieee802_1x_kay *kay);
 
 struct ieee802_1x_mka_participant *

wpa_supplicant/config.c

@@ -2612,6 +2612,7 @@ static const struct parse_data ssid_fields[] = {
 	{ INT(macsec_replay_window) },
 	{ INT_RANGE(macsec_port, 1, 65534) },
 	{ INT_RANGE(mka_priority, 0, 255) },
+	{ INT_RANGE(macsec_csindex, 0, 1) },
 	{ FUNC_KEY(mka_cak) },
 	{ FUNC_KEY(mka_ckn) },
 #endif /* CONFIG_MACSEC */

wpa_supplicant/config_file.c

@@ -810,6 +810,7 @@ static void wpa_config_write_network(FILE *f, struct wpa_ssid *ssid)
 	INT(macsec_replay_window);
 	INT(macsec_port);
 	INT_DEF(mka_priority, DEFAULT_PRIO_NOT_KEY_SERVER);
+	INT(macsec_csindex);
 #endif /* CONFIG_MACSEC */
 #ifdef CONFIG_HS20
 	INT(update_identifier);

wpa_supplicant/config_ssid.h

@@ -911,6 +911,13 @@ struct wpa_ssid {
 	 */
 	int mka_priority;
 
+	/**
+	 * macsec_csindex - Cipher suite index for MACsec
+	 *
+	 * Range: 0-1 (default: 0)
+	 */
+	int macsec_csindex;
+
 	/**
 	 * mka_ckn - MKA pre-shared CKN
 	 */

wpa_supplicant/wpas_kay.c

@@ -241,8 +241,8 @@ int ieee802_1x_alloc_kay_sm(struct wpa_supplicant *wpa_s, struct wpa_ssid *ssid)
 
 	res = ieee802_1x_kay_init(kay_ctx, policy, ssid->macsec_replay_protect,
 				  ssid->macsec_replay_window, ssid->macsec_port,
-				  ssid->mka_priority, wpa_s->ifname,
-				  wpa_s->own_addr);
+				  ssid->mka_priority, ssid->macsec_csindex,
+				  wpa_s->ifname, wpa_s->own_addr);
 	/* ieee802_1x_kay_init() frees kay_ctx on failure */
 	if (res == NULL)
 		return -1;