eap_tls.c
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00001 /*
00002  * EAP peer method: EAP-TLS (RFC 2716)
00003  * Copyright (c) 2004-2008, Jouni Malinen <j@w1.fi>
00004  *
00005  * This program is free software; you can redistribute it and/or modify
00006  * it under the terms of the GNU General Public License version 2 as
00007  * published by the Free Software Foundation.
00008  *
00009  * Alternatively, this software may be distributed under the terms of BSD
00010  * license.
00011  *
00012  * See README and COPYING for more details.
00013  */
00014 
00015 #include "includes.h"
00016 
00017 #include "common.h"
00018 #include "crypto/tls.h"
00019 #include "eap_i.h"
00020 #include "eap_tls_common.h"
00021 #include "eap_config.h"
00022 
00023 
00024 static void eap_tls_deinit(struct eap_sm *sm, void *priv);
00025 
00026 
00027 struct eap_tls_data {
00028         struct eap_ssl_data ssl;
00029         u8 *key_data;
00030 };
00031 
00032 
00033 static void * eap_tls_init(struct eap_sm *sm)
00034 {
00035         struct eap_tls_data *data;
00036         struct eap_peer_config *config = eap_get_config(sm);
00037         if (config == NULL ||
00038             ((sm->init_phase2 ? config->private_key2 : config->private_key)
00039              == NULL &&
00040              (sm->init_phase2 ? config->engine2 : config->engine) == 0)) {
00041                 wpa_printf(MSG_INFO, "EAP-TLS: Private key not configured");
00042                 return NULL;
00043         }
00044 
00045         data = os_zalloc(sizeof(*data));
00046         if (data == NULL)
00047                 return NULL;
00048 
00049         if (eap_peer_tls_ssl_init(sm, &data->ssl, config)) {
00050                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
00051                 eap_tls_deinit(sm, data);
00052                 if (config->engine) {
00053                         wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting Smartcard "
00054                                    "PIN");
00055                         eap_sm_request_pin(sm);
00056                         sm->ignore = TRUE;
00057                 } else if (config->private_key && !config->private_key_passwd)
00058                 {
00059                         wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting private "
00060                                    "key passphrase");
00061                         eap_sm_request_passphrase(sm);
00062                         sm->ignore = TRUE;
00063                 }
00064                 return NULL;
00065         }
00066 
00067         return data;
00068 }
00069 
00070 
00071 static void eap_tls_deinit(struct eap_sm *sm, void *priv)
00072 {
00073         struct eap_tls_data *data = priv;
00074         if (data == NULL)
00075                 return;
00076         eap_peer_tls_ssl_deinit(sm, &data->ssl);
00077         os_free(data->key_data);
00078         os_free(data);
00079 }
00080 
00081 
00082 static struct wpabuf * eap_tls_failure(struct eap_sm *sm,
00083                                        struct eap_tls_data *data,
00084                                        struct eap_method_ret *ret, int res,
00085                                        struct wpabuf *resp, u8 id)
00086 {
00087         wpa_printf(MSG_DEBUG, "EAP-TLS: TLS processing failed");
00088 
00089         ret->methodState = METHOD_DONE;
00090         ret->decision = DECISION_FAIL;
00091 
00092         if (res == -1) {
00093                 struct eap_peer_config *config = eap_get_config(sm);
00094                 if (config) {
00095                         /*
00096                          * The TLS handshake failed. So better forget the old
00097                          * PIN. It may be wrong, we cannot be sure but trying
00098                          * the wrong one again might block it on the card--so
00099                          * better ask the user again.
00100                          */
00101                         os_free(config->pin);
00102                         config->pin = NULL;
00103                 }
00104         }
00105 
00106         if (resp) {
00107                 /*
00108                  * This is likely an alert message, so send it instead of just
00109                  * ACKing the error.
00110                  */
00111                 return resp;
00112         }
00113 
00114         return eap_peer_tls_build_ack(id, EAP_TYPE_TLS, 0);
00115 }
00116 
00117 
00118 static void eap_tls_success(struct eap_sm *sm, struct eap_tls_data *data,
00119                             struct eap_method_ret *ret)
00120 {
00121         wpa_printf(MSG_DEBUG, "EAP-TLS: Done");
00122 
00123         ret->methodState = METHOD_DONE;
00124         ret->decision = DECISION_UNCOND_SUCC;
00125 
00126         os_free(data->key_data);
00127         data->key_data = eap_peer_tls_derive_key(sm, &data->ssl,
00128                                                  "client EAP encryption",
00129                                                  EAP_TLS_KEY_LEN +
00130                                                  EAP_EMSK_LEN);
00131         if (data->key_data) {
00132                 wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived key",
00133                                 data->key_data, EAP_TLS_KEY_LEN);
00134                 wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived EMSK",
00135                                 data->key_data + EAP_TLS_KEY_LEN,
00136                                 EAP_EMSK_LEN);
00137         } else {
00138                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to derive key");
00139         }
00140 }
00141 
00142 
00143 static struct wpabuf * eap_tls_process(struct eap_sm *sm, void *priv,
00144                                        struct eap_method_ret *ret,
00145                                        const struct wpabuf *reqData)
00146 {
00147         size_t left;
00148         int res;
00149         struct wpabuf *resp;
00150         u8 flags, id;
00151         const u8 *pos;
00152         struct eap_tls_data *data = priv;
00153 
00154         pos = eap_peer_tls_process_init(sm, &data->ssl, EAP_TYPE_TLS, ret,
00155                                         reqData, &left, &flags);
00156         if (pos == NULL)
00157                 return NULL;
00158         id = eap_get_id(reqData);
00159 
00160         if (flags & EAP_TLS_FLAGS_START) {
00161                 wpa_printf(MSG_DEBUG, "EAP-TLS: Start");
00162                 left = 0; /* make sure that this frame is empty, even though it
00163                            * should always be, anyway */
00164         }
00165 
00166         resp = NULL;
00167         res = eap_peer_tls_process_helper(sm, &data->ssl, EAP_TYPE_TLS, 0, id,
00168                                           pos, left, &resp);
00169 
00170         if (res < 0) {
00171                 return eap_tls_failure(sm, data, ret, res, resp, id);
00172         }
00173 
00174         if (tls_connection_established(sm->ssl_ctx, data->ssl.conn))
00175                 eap_tls_success(sm, data, ret);
00176 
00177         if (res == 1) {
00178                 wpabuf_free(resp);
00179                 return eap_peer_tls_build_ack(id, EAP_TYPE_TLS, 0);
00180         }
00181 
00182         return resp;
00183 }
00184 
00185 
00186 static Boolean eap_tls_has_reauth_data(struct eap_sm *sm, void *priv)
00187 {
00188         struct eap_tls_data *data = priv;
00189         return tls_connection_established(sm->ssl_ctx, data->ssl.conn);
00190 }
00191 
00192 
00193 static void eap_tls_deinit_for_reauth(struct eap_sm *sm, void *priv)
00194 {
00195 }
00196 
00197 
00198 static void * eap_tls_init_for_reauth(struct eap_sm *sm, void *priv)
00199 {
00200         struct eap_tls_data *data = priv;
00201         os_free(data->key_data);
00202         data->key_data = NULL;
00203         if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
00204                 os_free(data);
00205                 return NULL;
00206         }
00207         return priv;
00208 }
00209 
00210 
00211 static int eap_tls_get_status(struct eap_sm *sm, void *priv, char *buf,
00212                               size_t buflen, int verbose)
00213 {
00214         struct eap_tls_data *data = priv;
00215         return eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
00216 }
00217 
00218 
00219 static Boolean eap_tls_isKeyAvailable(struct eap_sm *sm, void *priv)
00220 {
00221         struct eap_tls_data *data = priv;
00222         return data->key_data != NULL;
00223 }
00224 
00225 
00226 static u8 * eap_tls_getKey(struct eap_sm *sm, void *priv, size_t *len)
00227 {
00228         struct eap_tls_data *data = priv;
00229         u8 *key;
00230 
00231         if (data->key_data == NULL)
00232                 return NULL;
00233 
00234         key = os_malloc(EAP_TLS_KEY_LEN);
00235         if (key == NULL)
00236                 return NULL;
00237 
00238         *len = EAP_TLS_KEY_LEN;
00239         os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
00240 
00241         return key;
00242 }
00243 
00244 
00245 static u8 * eap_tls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
00246 {
00247         struct eap_tls_data *data = priv;
00248         u8 *key;
00249 
00250         if (data->key_data == NULL)
00251                 return NULL;
00252 
00253         key = os_malloc(EAP_EMSK_LEN);
00254         if (key == NULL)
00255                 return NULL;
00256 
00257         *len = EAP_EMSK_LEN;
00258         os_memcpy(key, data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
00259 
00260         return key;
00261 }
00262 
00263 
00264 int eap_peer_tls_register(void)
00265 {
00266         struct eap_method *eap;
00267         int ret;
00268 
00269         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
00270                                     EAP_VENDOR_IETF, EAP_TYPE_TLS, "TLS");
00271         if (eap == NULL)
00272                 return -1;
00273 
00274         eap->init = eap_tls_init;
00275         eap->deinit = eap_tls_deinit;
00276         eap->process = eap_tls_process;
00277         eap->isKeyAvailable = eap_tls_isKeyAvailable;
00278         eap->getKey = eap_tls_getKey;
00279         eap->get_status = eap_tls_get_status;
00280         eap->has_reauth_data = eap_tls_has_reauth_data;
00281         eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
00282         eap->init_for_reauth = eap_tls_init_for_reauth;
00283         eap->get_emsk = eap_tls_get_emsk;
00284 
00285         ret = eap_peer_method_register(eap);
00286         if (ret)
00287                 eap_peer_method_free(eap);
00288         return ret;
00289 }


wpa_supplicant
Author(s): Package maintained by Blaise Gassend
autogenerated on Thu Jan 2 2014 11:26:37