EAP-TTLS server: Add support for session resumption

This allows TLS session resumption to be used to enable abbreviated
handshake and skipping of Phase 2.

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/src/eap_server/eap_server_ttls.c b/src/eap_server/eap_server_ttls.c
index 6766dd2..53ffa1e 100644 (file)
--- a/src/eap_server/eap_server_ttls.c
+++ b/src/eap_server/eap_server_ttls.c
@@ -71,6 +71,36 @@ static void eap_ttls_state(struct eap_ttls_data *data, int state)
                   eap_ttls_state_txt(data->state),
                   eap_ttls_state_txt(state));
        data->state = state;
+       if (state == FAILURE)
+               tls_connection_remove_session(data->ssl.conn);
+}
+
+
+static void eap_ttls_valid_session(struct eap_sm *sm,
+                                  struct eap_ttls_data *data)
+{
+       struct wpabuf *buf;
+
+       if (!sm->tls_session_lifetime)
+               return;
+
+       buf = wpabuf_alloc(1 + 1 + sm->identity_len);
+       if (!buf)
+               return;
+       wpabuf_put_u8(buf, EAP_TYPE_TTLS);
+       if (sm->identity) {
+               u8 id_len;
+
+               if (sm->identity_len <= 255)
+                       id_len = sm->identity_len;
+               else
+                       id_len = 255;
+               wpabuf_put_u8(buf, id_len);
+               wpabuf_put_data(buf, sm->identity, id_len);
+       } else {
+               wpabuf_put_u8(buf, 0);
+       }
+       tls_connection_set_success_data(data->ssl.conn, buf);
 }
 
 
@@ -518,6 +548,7 @@ static void eap_ttls_process_phase2_pap(struct eap_sm *sm,
 
        wpa_printf(MSG_DEBUG, "EAP-TTLS/PAP: Correct user password");
        eap_ttls_state(data, SUCCESS);
+       eap_ttls_valid_session(sm, data);
 }
 
 
@@ -576,6 +607,7 @@ static void eap_ttls_process_phase2_chap(struct eap_sm *sm,
            0) {
                wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Correct user password");
                eap_ttls_state(data, SUCCESS);
+               eap_ttls_valid_session(sm, data);
        } else {
                wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Invalid user password");
                eap_ttls_state(data, FAILURE);
@@ -643,6 +675,7 @@ static void eap_ttls_process_phase2_mschap(struct eap_sm *sm,
        if (os_memcmp_const(nt_response, response + 2 + 24, 24) == 0) {
                wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Correct response");
                eap_ttls_state(data, SUCCESS);
+               eap_ttls_valid_session(sm, data);
        } else {
                wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Invalid NT-Response");
                wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAP: Received",
@@ -906,6 +939,7 @@ static void eap_ttls_process_phase2_eap_response(struct eap_sm *sm,
                break;
        case PHASE2_METHOD:
                eap_ttls_state(data, SUCCESS);
+               eap_ttls_valid_session(sm, data);
                break;
        case FAILURE:
                break;
@@ -1129,6 +1163,7 @@ static void eap_ttls_process_msg(struct eap_sm *sm, void *priv,
                        wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Peer "
                                   "acknowledged response");
                        eap_ttls_state(data, SUCCESS);
+                       eap_ttls_valid_session(sm, data);
                } else if (!data->mschapv2_resp_ok) {
                        wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Peer "
                                   "acknowledged error");
@@ -1155,10 +1190,64 @@ static void eap_ttls_process(struct eap_sm *sm, void *priv,
                             struct wpabuf *respData)
 {
        struct eap_ttls_data *data = priv;
+       const struct wpabuf *buf;
+       const u8 *pos;
+       u8 id_len;
+
        if (eap_server_tls_process(sm, &data->ssl, respData, data,
                                   EAP_TYPE_TTLS, eap_ttls_process_version,
-                                  eap_ttls_process_msg) < 0)
+                                  eap_ttls_process_msg) < 0) {
+               eap_ttls_state(data, FAILURE);
+               return;
+       }
+
+       if (!tls_connection_established(sm->ssl_ctx, data->ssl.conn) ||
+           !tls_connection_resumed(sm->ssl_ctx, data->ssl.conn))
+               return;
+
+       buf = tls_connection_get_success_data(data->ssl.conn);
+       if (!buf || wpabuf_len(buf) < 1) {
+               wpa_printf(MSG_DEBUG,
+                          "EAP-TTLS: No success data in resumed session - reject attempt");
                eap_ttls_state(data, FAILURE);
+               return;
+       }
+
+       pos = wpabuf_head(buf);
+       if (*pos != EAP_TYPE_TTLS) {
+               wpa_printf(MSG_DEBUG,
+                          "EAP-TTLS: Resumed session for another EAP type (%u) - reject attempt",
+                          *pos);
+               eap_ttls_state(data, FAILURE);
+               return;
+       }
+
+       pos++;
+       id_len = *pos++;
+       wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: Identity from cached session",
+                         pos, id_len);
+       os_free(sm->identity);
+       sm->identity = os_malloc(id_len ? id_len : 1);
+       if (!sm->identity) {
+               sm->identity_len = 0;
+               eap_ttls_state(data, FAILURE);
+               return;
+       }
+
+       os_memcpy(sm->identity, pos, id_len);
+       sm->identity_len = id_len;
+
+       if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
+               wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: Phase2 Identity not found in the user database",
+                                 sm->identity, sm->identity_len);
+               eap_ttls_state(data, FAILURE);
+               return;
+       }
+
+       wpa_printf(MSG_DEBUG,
+                  "EAP-TTLS: Resuming previous session - skip Phase2");
+       eap_ttls_state(data, SUCCESS);
+       tls_connection_set_success_data_resumed(data->ssl.conn);
 }