OCV: Add wpa_supplicant config parameter

Add wpa_supplicant network profile parameter ocv to disable or enable
Operating Channel Verification (OCV) support.

Signed-off-by: Mathy Vanhoef <Mathy.Vanhoef@cs.kuleuven.be>

wpa_supplicant/config.c

@@ -2059,6 +2059,43 @@ static char * wpa_config_write_mka_ckn(const struct parse_data *data,
 #endif /* CONFIG_MACSEC */
 
 
+#ifdef CONFIG_OCV
+
+static int wpa_config_parse_ocv(const struct parse_data *data,
+				struct wpa_ssid *ssid, int line,
+				const char *value)
+{
+	char *end;
+
+	ssid->ocv = strtol(value, &end, 0);
+	if (*end || ssid->ocv < 0 || ssid->ocv > 1) {
+		wpa_printf(MSG_ERROR, "Line %d: Invalid ocv value '%s'.",
+			   line, value);
+		return -1;
+	}
+	if (ssid->ocv && ssid->ieee80211w == NO_MGMT_FRAME_PROTECTION)
+		ssid->ieee80211w = MGMT_FRAME_PROTECTION_OPTIONAL;
+	return 0;
+}
+
+
+#ifndef NO_CONFIG_WRITE
+static char * wpa_config_write_ocv(const struct parse_data *data,
+				   struct wpa_ssid *ssid)
+{
+	char *value = os_malloc(20);
+
+	if (!value)
+		return NULL;
+	os_snprintf(value, 20, "%d", ssid->ocv);
+	value[20 - 1] = '\0';
+	return value;
+}
+#endif /* NO_CONFIG_WRITE */
+
+#endif /* CONFIG_OCV */
+
+
 static int wpa_config_parse_peerkey(const struct parse_data *data,
 				    struct wpa_ssid *ssid, int line,
 				    const char *value)
@@ -2262,6 +2299,9 @@ static const struct parse_data ssid_fields[] = {
 #ifdef CONFIG_IEEE80211W
 	{ INT_RANGE(ieee80211w, 0, 2) },
 #endif /* CONFIG_IEEE80211W */
+#ifdef CONFIG_OCV
+	{ FUNC(ocv) },
+#endif /* CONFIG_OCV */
 	{ FUNC(peerkey) /* obsolete - removed */ },
 	{ INT_RANGE(mixed_cell, 0, 1) },
 	{ INT_RANGE(frequency, 0, 65000) },

wpa_supplicant/config_file.c

@@ -160,6 +160,15 @@ static int wpa_config_validate_network(struct wpa_ssid *ssid, int line)
 		errors++;
 	}
 
+#ifdef CONFIG_OCV
+	if (ssid->ocv && ssid->ieee80211w == NO_MGMT_FRAME_PROTECTION) {
+		wpa_printf(MSG_ERROR,
+			   "Line %d: PMF needs to be enabled whenever using OCV",
+			   line);
+		errors++;
+	}
+#endif /* CONFIG_OCV */
+
 	return errors;
 }
 

wpa_supplicant/config_ssid.h

@@ -457,6 +457,17 @@ struct wpa_ssid {
 	enum mfp_options ieee80211w;
 #endif /* CONFIG_IEEE80211W */
 
+#ifdef CONFIG_OCV
+	/**
+	 * ocv - Enable/disable operating channel validation
+	 *
+	 * If this parameter is set to 1, stations will exchange OCI element
+	 * to cryptographically verify the operating channel. Setting this
+	 * parameter to 0 disables this option. Default value: 0.
+	 */
+	int ocv;
+#endif /* CONFIG_OCV */
+
 	/**
 	 * frequency - Channel frequency in megahertz (MHz) for IBSS
 	 *

wpa_supplicant/wpa_supplicant.conf

@@ -907,6 +907,13 @@ fast_reauth=1
 # PMF required: ieee80211w=2 and key_mgmt=WPA-EAP-SHA256
 # (and similarly for WPA-PSK and WPA-WPSK-SHA256 if WPA2-Personal is used)
 #
+# ocv: whether operating channel validation is enabled
+# This is a countermeasure against multi-channel man-in-the-middle attacks.
+# Enabling this automatically also enables ieee80211w, if not yet enabled.
+# 0 = disabled (default)
+# 1 = enabled
+#ocv=1
+#
 # auth_alg: list of allowed IEEE 802.11 authentication algorithms
 # OPEN = Open System authentication (required for WPA/WPA2)
 # SHARED = Shared Key authentication (requires static WEP keys)