[2/4] dpp: add Address/Frequency as parameters to PKEX enrollees

Commit Message

James Prestwood Aug. 27, 2024, 2:21 p.m. UTC

The DPP spec allows for obtaining frequency and MAC addresses up
to the implementation. IWD already takes advantage of this by
first scanning for nearby APs and using only those frequencies.
For further optimization an enrollee may be able to determine the
configurators frequency and MAC ahead of time which would make
finding the configurator much faster.
---
 src/dpp.c | 43 ++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)

Patch

diff --git a/src/dpp.c b/src/dpp.c
index c1047ca3..39b66154 100644
--- a/src/dpp.c
+++ b/src/dpp.c
@@ -4345,6 +4345,12 @@  static bool dpp_start_pkex_enrollee(struct dpp_sm *dpp)
 {
 	dpp_property_changed_notify(dpp);
 
+	/* Already have a set (or single) frequency */
+	if (dpp->freqs) {
+		__dpp_pkex_start_enrollee(dpp);
+		return true;
+	}
+
 	/*
 	 * The 'dpp_default_freqs' function returns the default frequencies
 	 * outlined in section 5.6.1. For 2.4/5GHz this is only 3 frequencies
@@ -4374,13 +4380,17 @@  failed:
 
 static bool dpp_parse_pkex_args(struct l_dbus_message *message,
 					const char **key_out,
-					const char **id_out)
+					const char **id_out,
+					const char **mac_out,
+					uint32_t *freq_out)
 {
 	struct l_dbus_message_iter iter;
 	struct l_dbus_message_iter variant;
 	const char *dict_key;
 	const char *key = NULL;
 	const char *id = NULL;
+	const char *mac = NULL;
+	uint32_t freq = 0;
 
 	if (!l_dbus_message_get_arguments(message, "a{sv}", &iter))
 		return false;
@@ -4394,6 +4404,14 @@  static bool dpp_parse_pkex_args(struct l_dbus_message *message,
 			if (!l_dbus_message_iter_get_variant(&variant, "s",
 								&id))
 				return false;
+		} else if (!strcmp(dict_key, "Address")) {
+			if (!l_dbus_message_iter_get_variant(&variant, "s",
+								&mac))
+				return false;
+		} else if (!strcmp(dict_key, "Frequency")) {
+			if (!l_dbus_message_iter_get_variant(&variant, "u",
+								&freq))
+				return false;
 		}
 	}
 
@@ -4406,6 +4424,12 @@  static bool dpp_parse_pkex_args(struct l_dbus_message *message,
 	*key_out = key;
 	*id_out = id;
 
+	if (mac_out)
+		*mac_out = mac;
+
+	if (freq_out)
+		*freq_out = freq;
+
 	return true;
 }
 
@@ -4450,6 +4474,8 @@  static struct l_dbus_message *dpp_dbus_pkex_start_enrollee(struct l_dbus *dbus,
 	struct dpp_sm *dpp = user_data;
 	const char *key;
 	const char *id;
+	const char *mac_str;
+	uint32_t freq;
 	bool wait_for_disconnect;
 	int ret;
 
@@ -4459,8 +4485,19 @@  static struct l_dbus_message *dpp_dbus_pkex_start_enrollee(struct l_dbus *dbus,
 				dpp->interface != DPP_INTERFACE_UNBOUND)
 		return dbus_error_busy(message);
 
-	if (!dpp_parse_pkex_args(message, &key, &id))
+	if (!dpp_parse_pkex_args(message, &key, &id, &mac_str, &freq))
+		goto invalid_args;
+
+	if (mac_str && !util_string_to_address(mac_str, dpp->peer_addr))
 		goto invalid_args;
+	else if (!mac_str)
+		memcpy(dpp->peer_addr, broadcast, 6);
+
+	if (freq) {
+		dpp->freqs = l_new(uint32_t, 1);
+		dpp->freqs[0] = freq;
+		dpp->freqs_len = 1;
+	}
 
 	dpp->pkex_key = l_strdup(key);
 
@@ -4595,7 +4632,7 @@  static struct l_dbus_message *dpp_dbus_pkex_configure_enrollee(
 
 	l_debug("");
 
-	if (!dpp_parse_pkex_args(message, &key, &id))
+	if (!dpp_parse_pkex_args(message, &key, &id, NULL, NULL))
 		return dbus_error_invalid_args(message);
 
 	return dpp_start_pkex_configurator(dpp, key, id, NULL, message);