From 91d35987fd44dd30bf0b1af3a38215980e192382 Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Tue, 11 Oct 2016 01:36:48 -0500
Subject: [PATCH] eapol: Add provision to use EAPOL-Start

---
 src/eapol.c | 36 ++++++++++++++++++++++++++++++++++++
 src/eapol.h |  1 +
 2 files changed, 37 insertions(+)

diff --git a/src/eapol.c b/src/eapol.c
index 7f0ed0b9..b9413b67 100644
--- a/src/eapol.c
+++ b/src/eapol.c
@@ -726,11 +726,13 @@ struct eapol_sm {
 	eapol_sm_event_func_t event_func;
 	void *user_data;
 	struct l_timeout *timeout;
+	struct l_timeout *eapol_start_timeout;
 	bool have_snonce:1;
 	bool have_replay:1;
 	bool ptk_complete:1;
 	bool wpa_ie:1;
 	bool have_pmk:1;
+	bool use_eapol_start:1;
 	struct eap_state *eap;
 };
 
@@ -742,6 +744,7 @@ static void eapol_sm_destroy(void *value)
 	l_free(sm->own_ie);
 
 	l_timeout_remove(sm->timeout);
+	l_timeout_remove(sm->eapol_start_timeout);
 
 	if (sm->eap)
 		eap_free(sm->eap);
@@ -920,6 +923,22 @@ static void eapol_timeout(struct l_timeout *timeout, void *user_data)
 				MPDU_REASON_CODE_4WAY_HANDSHAKE_TIMEOUT);
 }
 
+static void send_eapol_start(struct l_timeout *timeout, void *user_data)
+{
+	struct eapol_sm *sm = user_data;
+	uint8_t buf[sizeof(struct eapol_frame)];
+	struct eapol_frame *frame = (struct eapol_frame *) buf;
+
+	l_timeout_remove(sm->eapol_start_timeout);
+	sm->eapol_start_timeout = NULL;
+
+	frame->header.protocol_version = sm->protocol_version;
+	frame->header.packet_type = 1;
+	l_put_be16(0, &frame->header.packet_len);
+
+	pae_write(sm->ifindex, sm->aa, sm->spa, frame);
+}
+
 static void eapol_handle_ptk_1_of_4(uint32_t ifindex, struct eapol_sm *sm,
 					const struct eapol_key *ek)
 {
@@ -1611,6 +1630,11 @@ void eapol_sm_set_8021x_config(struct eapol_sm *sm, struct l_settings *settings)
 	eap_set_event_func(sm->eap, eapol_eap_event_cb);
 }
 
+void eapol_sm_set_use_eapol_start(struct eapol_sm *sm, bool enabled)
+{
+	sm->use_eapol_start = enabled;
+}
+
 static void eapol_rx_packet(struct eapol_sm *sm,
 					const uint8_t *frame, size_t len)
 {
@@ -1638,6 +1662,9 @@ static void eapol_rx_packet(struct eapol_sm *sm,
 
 	switch (eh->packet_type) {
 	case 0: /* EAPOL-EAP */
+		l_timeout_remove(sm->eapol_start_timeout);
+		sm->eapol_start_timeout = 0;
+
 		if (!sm->eap) {
 			/* If we're not configured for EAP, send a NAK */
 			sm->eap = eap_new(eapol_eap_msg_cb,
@@ -1742,6 +1769,15 @@ void eapol_start(uint32_t ifindex, struct eapol_sm *sm)
 	sm->ifindex = ifindex;
 	sm->timeout = l_timeout_create(2, eapol_timeout, sm, NULL);
 
+	if (sm->use_eapol_start) {
+		/*
+		 * We start a short timeout, if EAP packets are not received
+		 * from AP, then we send the EAPoL-Start
+		 */
+		sm->eapol_start_timeout =
+				l_timeout_create(1, send_eapol_start, sm, NULL);
+	}
+
 	l_queue_push_head(state_machines, sm);
 }
 
diff --git a/src/eapol.h b/src/eapol.h
index 425050a1..e5a50764 100644
--- a/src/eapol.h
+++ b/src/eapol.h
@@ -191,6 +191,7 @@ void eapol_sm_set_authenticator_address(struct eapol_sm *sm, const uint8_t *aa);
 void eapol_sm_set_pmk(struct eapol_sm *sm, const uint8_t *pmk);
 void eapol_sm_set_8021x_config(struct eapol_sm *sm,
 				struct l_settings *settings);
+void eapol_sm_set_use_eapol_start(struct eapol_sm *sm, bool enabled);
 void eapol_sm_set_ap_rsn(struct eapol_sm *sm, const uint8_t *rsn_ie,
 				size_t len);
 bool eapol_sm_set_own_rsn(struct eapol_sm *sm, const uint8_t *rsn_ie,