From eda02fb92987b95fd4d045c7193bd648b8107b0e Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Tue, 3 Jan 2023 09:58:29 -0600
Subject: [PATCH] eap-peap: Fix failures with session resumption

The PEAP RFC wants implementations to enforce that Phase2 methods have
been successfully completed prior to accepting a successful result TLV.
However, when TLS session resumption is used, some servers will skip
phase2 methods entirely and simply send a Result TLV with a success
code.  This results in iwd (erroneously) rejecting the authentication
attempt.

Fix this by marking phase2 method as successful if session resumption is
being used.
---
 src/eap-peap.c       | 12 +++++++++++-
 src/eap-tls-common.c |  3 ++-
 src/eap-tls-common.h |  3 ++-
 src/eap-tls.c        |  3 ++-
 src/eap-ttls.c       |  3 ++-
 5 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/eap-peap.c b/src/eap-peap.c
index 38ecd6a9..785bfc81 100644
--- a/src/eap-peap.c
+++ b/src/eap-peap.c
@@ -468,7 +468,8 @@ static void eap_extensions_handle_request(struct eap_state *eap,
 }
 
 static bool eap_peap_tunnel_ready(struct eap_state *eap,
-						const char *peer_identity)
+						const char *peer_identity,
+						bool resumed)
 {
 	struct peap_state *peap_state = eap_tls_common_get_variant_data(eap);
 
@@ -480,6 +481,15 @@ static bool eap_peap_tunnel_ready(struct eap_state *eap,
 	*/
 	eap_discard_success_and_failure(eap, true);
 
+	/*
+	 * In case of a resumed session, the server will typically not run
+	 * phase2 methods at all, but will instead send a result TLV right
+	 * away.  Treat this like a successful phase2.  In case the server
+	 * does proceed with phase2, the success/failure state will be updated.
+	 */
+	if (resumed)
+		eap_method_success(peap_state->phase2);
+
 	/* MSK, EMSK and challenge derivation */
 	eap_tls_common_tunnel_prf_get_bytes(eap, true, "client EAP encryption",
 						peap_state->key, 128);
diff --git a/src/eap-tls-common.c b/src/eap-tls-common.c
index 9a4450e9..784a57ee 100644
--- a/src/eap-tls-common.c
+++ b/src/eap-tls-common.c
@@ -244,6 +244,7 @@ static void eap_tls_tunnel_ready(const char *peer_identity, void *user_data)
 {
 	struct eap_state *eap = user_data;
 	struct eap_tls_state *eap_tls = eap_get_data(eap);
+	bool resumed = l_tls_get_session_resumed(eap_tls->tunnel);
 
 	if (eap_tls->ca_cert && !peer_identity) {
 		l_error("%s: TLS did not verify AP identity",
@@ -264,7 +265,7 @@ static void eap_tls_tunnel_ready(const char *peer_identity, void *user_data)
 	if (!eap_tls->variant_ops->tunnel_ready)
 		return;
 
-	if (!eap_tls->variant_ops->tunnel_ready(eap, peer_identity))
+	if (!eap_tls->variant_ops->tunnel_ready(eap, peer_identity, resumed))
 		l_tls_close(eap_tls->tunnel);
 }
 
diff --git a/src/eap-tls-common.h b/src/eap-tls-common.h
index 25f668e2..bfc23c08 100644
--- a/src/eap-tls-common.h
+++ b/src/eap-tls-common.h
@@ -33,7 +33,8 @@ enum eap_tls_version {
 struct eap_tls_variant_ops {
 	enum eap_tls_version version_max_supported;
 
-	bool (*tunnel_ready)(struct eap_state *eap, const char *peer_identity);
+	bool (*tunnel_ready)(struct eap_state *eap, const char *peer_identity,
+				bool resumed);
 	bool (*tunnel_handle_request)(struct eap_state *eap,
 					const uint8_t *data, size_t data_len);
 	void (*reset)(void *variant_data);
diff --git a/src/eap-tls.c b/src/eap-tls.c
index ecea94d9..56fdc67f 100644
--- a/src/eap-tls.c
+++ b/src/eap-tls.c
@@ -35,7 +35,8 @@
 #include "src/eap-tls-common.h"
 
 static bool eap_tls_tunnel_ready(struct eap_state *eap,
-						const char *peer_identity)
+						const char *peer_identity,
+						bool resumed)
 {
 	uint8_t msk_emsk[128];
 	uint8_t iv[64];
diff --git a/src/eap-ttls.c b/src/eap-ttls.c
index 672a47c6..43a6c118 100644
--- a/src/eap-ttls.c
+++ b/src/eap-ttls.c
@@ -902,7 +902,8 @@ static const struct phase2_method_ops phase2_eap_ops = {
 };
 
 static bool eap_ttls_tunnel_ready(struct eap_state *eap,
-						const char *peer_identity)
+						const char *peer_identity,
+						bool resumed)
 {
 	struct phase2_method *phase2 = eap_tls_common_get_variant_data(eap);
 	uint8_t msk_emsk[128];