mka: Make MKA actor priority configurable

This adds a new wpa_supplicant network profile parameter
mka_priority=0..255 to set the priority of the MKA Actor.

Signed-off-by: Badrish Adiga H R <badrish.adigahr@gmail.com>

src/pae/ieee802_1x_kay.c

@@ -3083,7 +3083,7 @@ 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,
-		    u16 port, const char *ifname, const u8 *addr)
+		    u16 port, u8 priority, const char *ifname, const u8 *addr)
 {
 	struct ieee802_1x_kay *kay;
 
@@ -3106,7 +3106,7 @@ ieee802_1x_kay_init(struct ieee802_1x_kay_ctx *ctx, enum macsec_policy policy,
 	os_strlcpy(kay->if_name, ifname, IFNAMSIZ);
 	os_memcpy(kay->actor_sci.addr, addr, ETH_ALEN);
 	kay->actor_sci.port = host_to_be16(port ? port : 0x0001);
-	kay->actor_priority = DEFAULT_PRIO_NOT_KEY_SERVER;
+	kay->actor_priority = priority;
 
 	/* While actor acts as a key server, shall distribute sakey */
 	kay->dist_kn = 1;

src/pae/ieee802_1x_kay.h

@@ -236,7 +236,7 @@ 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,
-		    u16 port, const char *ifname, const u8 *addr);
+		    u16 port, u8 priority, 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

@@ -11,6 +11,7 @@
 #include "common.h"
 #include "utils/uuid.h"
 #include "utils/ip_addr.h"
+#include "common/ieee802_1x_defs.h"
 #include "crypto/sha1.h"
 #include "rsn_supp/wpa.h"
 #include "eap_peer/eap.h"
@@ -2127,6 +2128,7 @@ static const struct parse_data ssid_fields[] = {
 	{ INT_RANGE(macsec_policy, 0, 1) },
 	{ INT_RANGE(macsec_integ_only, 0, 1) },
 	{ INT_RANGE(macsec_port, 1, 65534) },
+	{ INT_RANGE(mka_priority, 0, 255) },
 	{ FUNC_KEY(mka_cak) },
 	{ FUNC_KEY(mka_ckn) },
 #endif /* CONFIG_MACSEC */
@@ -2617,6 +2619,9 @@ void wpa_config_set_network_defaults(struct wpa_ssid *ssid)
 #ifdef CONFIG_IEEE80211W
 	ssid->ieee80211w = MGMT_FRAME_PROTECTION_DEFAULT;
 #endif /* CONFIG_IEEE80211W */
+#ifdef CONFIG_MACSEC
+	ssid->mka_priority = DEFAULT_PRIO_NOT_KEY_SERVER;
+#endif /* CONFIG_MACSEC */
 	ssid->mac_addr = -1;
 }
 

wpa_supplicant/config_file.c

@@ -19,6 +19,7 @@
 #include "config.h"
 #include "base64.h"
 #include "uuid.h"
+#include "common/ieee802_1x_defs.h"
 #include "p2p/p2p.h"
 #include "eap_peer/eap_methods.h"
 #include "eap_peer/eap.h"
@@ -813,6 +814,7 @@ static void wpa_config_write_network(FILE *f, struct wpa_ssid *ssid)
 	write_mka_ckn(f, ssid);
 	INT(macsec_integ_only);
 	INT(macsec_port);
+	INT_DEF(mka_priority, DEFAULT_PRIO_NOT_KEY_SERVER);
 #endif /* CONFIG_MACSEC */
 #ifdef CONFIG_HS20
 	INT(update_identifier);

wpa_supplicant/config_ssid.h

@@ -750,6 +750,13 @@ struct wpa_ssid {
 	 */
 	int macsec_port;
 
+	/**
+	 * mka_priority - Priority of MKA Actor
+	 *
+	 * Range: 0-255 (default: 255)
+	 */
+	int mka_priority;
+
 	/**
 	 * mka_ckn - MKA pre-shared CKN
 	 */

wpa_supplicant/wpa_cli.c

@@ -1392,6 +1392,7 @@ static const char *network_fields[] = {
 	"macsec_policy",
 	"macsec_integ_only",
 	"macsec_port",
+	"mka_priority",
 #endif /* CONFIG_MACSEC */
 #ifdef CONFIG_HS20
 	"update_identifier",

wpa_supplicant/wpa_supplicant.conf

@@ -901,13 +901,15 @@ fast_reauth=1
 # Port component of the SCI
 # Range: 1-65534 (default: 1)
 #
-# mka_cak and mka_ckn: IEEE 802.1X/MACsec pre-shared authentication mode
+# 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 wpa_supplicant can act as peers, one of
-# which will become the key server and start distributing SAKs.
+# In this mode, instances of wpa_supplicant can act as MACsec peers. The peer
+# with lower priority will become the key server and start distributing SAKs.
 # mka_cak (CAK = Secure Connectivity Association Key) takes a 16-bytes (128 bit)
 # hex-string (32 hex-digits)
 # mka_ckn (CKN = CAK Name) takes a 32-bytes (256 bit) hex-string (64 hex-digits)
+# mka_priority (Priority of MKA Actor) is in 0..255 range with 255 being
+# default priority
 #
 # mixed_cell: This option can be used to configure whether so called mixed
 # cells, i.e., networks that use both plaintext and encryption in the same

wpa_supplicant/wpas_kay.c

@@ -233,7 +233,8 @@ int ieee802_1x_alloc_kay_sm(struct wpa_supplicant *wpa_s, struct wpa_ssid *ssid)
 	kay_ctx->disable_transmit_sa = wpas_disable_transmit_sa;
 
 	res = ieee802_1x_kay_init(kay_ctx, policy, ssid->macsec_port,
-				  wpa_s->ifname, wpa_s->own_addr);
+				  ssid->mka_priority, wpa_s->ifname,
+				  wpa_s->own_addr);
 	if (res == NULL) {
 		os_free(kay_ctx);
 		return -1;