contrib/hostapd/src/eap_peer/eap_tls.c

   1 /*
   2  * EAP peer method: EAP-TLS (RFC 2716)
   3  * Copyright (c) 2004-2008, 2012, Jouni Malinen <j@w1.fi>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #include "includes.h"
  10
  11 #include "common.h"
  12 #include "crypto/tls.h"
  13 #include "eap_i.h"
  14 #include "eap_tls_common.h"
  15 #include "eap_config.h"
  16
  17
  18 static void eap_tls_deinit(struct eap_sm *sm, void *priv);
  19
  20
  21 struct eap_tls_data {
  22         struct eap_ssl_data ssl;
  23         u8 *key_data;
  24         u8 *session_id;
  25         size_t id_len;
  26         void *ssl_ctx;
  27         u8 eap_type;
  28 };
  29
  30
  31 static void * eap_tls_init(struct eap_sm *sm)
  32 {
  33         struct eap_tls_data *data;
  34         struct eap_peer_config *config = eap_get_config(sm);
  35         if (config == NULL ||
  36             ((sm->init_phase2 ? config->private_key2 : config->private_key)
  37              == NULL &&
  38              (sm->init_phase2 ? config->engine2 : config->engine) == 0)) {
  39                 wpa_printf(MSG_INFO, "EAP-TLS: Private key not configured");
  40                 return NULL;
  41         }
  42
  43         data = os_zalloc(sizeof(*data));
  44         if (data == NULL)
  45                 return NULL;
  46
  47         data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
  48                 sm->ssl_ctx;
  49
  50         if (eap_peer_tls_ssl_init(sm, &data->ssl, config, EAP_TYPE_TLS)) {
  51                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
  52                 eap_tls_deinit(sm, data);
  53                 if (config->engine) {
  54                         wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting Smartcard "
  55                                    "PIN");
  56                         eap_sm_request_pin(sm);
  57                         sm->ignore = TRUE;
  58                 } else if (config->private_key && !config->private_key_passwd)
  59                 {
  60                         wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting private "
  61                                    "key passphrase");
  62                         eap_sm_request_passphrase(sm);
  63                         sm->ignore = TRUE;
  64                 }
  65                 return NULL;
  66         }
  67
  68         data->eap_type = EAP_TYPE_TLS;
  69
  70         return data;
  71 }
  72
  73
  74 #ifdef EAP_UNAUTH_TLS
  75 static void * eap_unauth_tls_init(struct eap_sm *sm)
  76 {
  77         struct eap_tls_data *data;
  78         struct eap_peer_config *config = eap_get_config(sm);
  79
  80         data = os_zalloc(sizeof(*data));
  81         if (data == NULL)
  82                 return NULL;
  83
  84         data->ssl_ctx = sm->init_phase2 && sm->ssl_ctx2 ? sm->ssl_ctx2 :
  85                 sm->ssl_ctx;
  86
  87         if (eap_peer_tls_ssl_init(sm, &data->ssl, config,
  88                                   EAP_UNAUTH_TLS_TYPE)) {
  89                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
  90                 eap_tls_deinit(sm, data);
  91                 return NULL;
  92         }
  93
  94         data->eap_type = EAP_UNAUTH_TLS_TYPE;
  95
  96         return data;
  97 }
  98 #endif /* EAP_UNAUTH_TLS */
  99
 100
 101 static void eap_tls_deinit(struct eap_sm *sm, void *priv)
 102 {
 103         struct eap_tls_data *data = priv;
 104         if (data == NULL)
 105                 return;
 106         eap_peer_tls_ssl_deinit(sm, &data->ssl);
 107         os_free(data->key_data);
 108         os_free(data->session_id);
 109         os_free(data);
 110 }
 111
 112
 113 static struct wpabuf * eap_tls_failure(struct eap_sm *sm,
 114                                        struct eap_tls_data *data,
 115                                        struct eap_method_ret *ret, int res,
 116                                        struct wpabuf *resp, u8 id)
 117 {
 118         wpa_printf(MSG_DEBUG, "EAP-TLS: TLS processing failed");
 119
 120         ret->methodState = METHOD_DONE;
 121         ret->decision = DECISION_FAIL;
 122
 123         if (res == -1) {
 124                 struct eap_peer_config *config = eap_get_config(sm);
 125                 if (config) {
 126                         /*
 127                          * The TLS handshake failed. So better forget the old
 128                          * PIN. It may be wrong, we cannot be sure but trying
 129                          * the wrong one again might block it on the card--so
 130                          * better ask the user again.
 131                          */
 132                         os_free(config->pin);
 133                         config->pin = NULL;
 134                 }
 135         }
 136
 137         if (resp) {
 138                 /*
 139                  * This is likely an alert message, so send it instead of just
 140                  * ACKing the error.
 141                  */
 142                 return resp;
 143         }
 144
 145         return eap_peer_tls_build_ack(id, data->eap_type, 0);
 146 }
 147
 148
 149 static void eap_tls_success(struct eap_sm *sm, struct eap_tls_data *data,
 150                             struct eap_method_ret *ret)
 151 {
 152         wpa_printf(MSG_DEBUG, "EAP-TLS: Done");
 153
 154         ret->methodState = METHOD_DONE;
 155         ret->decision = DECISION_UNCOND_SUCC;
 156
 157         os_free(data->key_data);
 158         data->key_data = eap_peer_tls_derive_key(sm, &data->ssl,
 159                                                  "client EAP encryption",
 160                                                  EAP_TLS_KEY_LEN +
 161                                                  EAP_EMSK_LEN);
 162         if (data->key_data) {
 163                 wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived key",
 164                                 data->key_data, EAP_TLS_KEY_LEN);
 165                 wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived EMSK",
 166                                 data->key_data + EAP_TLS_KEY_LEN,
 167                                 EAP_EMSK_LEN);
 168         } else {
 169                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to derive key");
 170         }
 171
 172         os_free(data->session_id);
 173         data->session_id = eap_peer_tls_derive_session_id(sm, &data->ssl,
 174                                                           EAP_TYPE_TLS,
 175                                                           &data->id_len);
 176         if (data->session_id) {
 177                 wpa_hexdump(MSG_DEBUG, "EAP-TLS: Derived Session-Id",
 178                             data->session_id, data->id_len);
 179         } else {
 180                 wpa_printf(MSG_ERROR, "EAP-TLS: Failed to derive Session-Id");
 181         }
 182 }
 183
 184
 185 static struct wpabuf * eap_tls_process(struct eap_sm *sm, void *priv,
 186                                        struct eap_method_ret *ret,
 187                                        const struct wpabuf *reqData)
 188 {
 189         size_t left;
 190         int res;
 191         struct wpabuf *resp;
 192         u8 flags, id;
 193         const u8 *pos;
 194         struct eap_tls_data *data = priv;
 195
 196         pos = eap_peer_tls_process_init(sm, &data->ssl, data->eap_type, ret,
 197                                         reqData, &left, &flags);
 198         if (pos == NULL)
 199                 return NULL;
 200         id = eap_get_id(reqData);
 201
 202         if (flags & EAP_TLS_FLAGS_START) {
 203                 wpa_printf(MSG_DEBUG, "EAP-TLS: Start");
 204                 left = 0; /* make sure that this frame is empty, even though it
 205                            * should always be, anyway */
 206         }
 207
 208         resp = NULL;
 209         res = eap_peer_tls_process_helper(sm, &data->ssl, data->eap_type, 0,
 210                                           id, pos, left, &resp);
 211
 212         if (res < 0) {
 213                 return eap_tls_failure(sm, data, ret, res, resp, id);
 214         }
 215
 216         if (tls_connection_established(data->ssl_ctx, data->ssl.conn))
 217                 eap_tls_success(sm, data, ret);
 218
 219         if (res == 1) {
 220                 wpabuf_free(resp);
 221                 return eap_peer_tls_build_ack(id, data->eap_type, 0);
 222         }
 223
 224         return resp;
 225 }
 226
 227
 228 static Boolean eap_tls_has_reauth_data(struct eap_sm *sm, void *priv)
 229 {
 230         struct eap_tls_data *data = priv;
 231         return tls_connection_established(data->ssl_ctx, data->ssl.conn);
 232 }
 233
 234
 235 static void eap_tls_deinit_for_reauth(struct eap_sm *sm, void *priv)
 236 {
 237 }
 238
 239
 240 static void * eap_tls_init_for_reauth(struct eap_sm *sm, void *priv)
 241 {
 242         struct eap_tls_data *data = priv;
 243         os_free(data->key_data);
 244         data->key_data = NULL;
 245         os_free(data->session_id);
 246         data->session_id = NULL;
 247         if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
 248                 os_free(data);
 249                 return NULL;
 250         }
 251         return priv;
 252 }
 253
 254
 255 static int eap_tls_get_status(struct eap_sm *sm, void *priv, char *buf,
 256                               size_t buflen, int verbose)
 257 {
 258         struct eap_tls_data *data = priv;
 259         return eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
 260 }
 261
 262
 263 static Boolean eap_tls_isKeyAvailable(struct eap_sm *sm, void *priv)
 264 {
 265         struct eap_tls_data *data = priv;
 266         return data->key_data != NULL;
 267 }
 268
 269
 270 static u8 * eap_tls_getKey(struct eap_sm *sm, void *priv, size_t *len)
 271 {
 272         struct eap_tls_data *data = priv;
 273         u8 *key;
 274
 275         if (data->key_data == NULL)
 276                 return NULL;
 277
 278         key = os_malloc(EAP_TLS_KEY_LEN);
 279         if (key == NULL)
 280                 return NULL;
 281
 282         *len = EAP_TLS_KEY_LEN;
 283         os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
 284
 285         return key;
 286 }
 287
 288
 289 static u8 * eap_tls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
 290 {
 291         struct eap_tls_data *data = priv;
 292         u8 *key;
 293
 294         if (data->key_data == NULL)
 295                 return NULL;
 296
 297         key = os_malloc(EAP_EMSK_LEN);
 298         if (key == NULL)
 299                 return NULL;
 300
 301         *len = EAP_EMSK_LEN;
 302         os_memcpy(key, data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
 303
 304         return key;
 305 }
 306
 307
 308 static u8 * eap_tls_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
 309 {
 310         struct eap_tls_data *data = priv;
 311         u8 *id;
 312
 313         if (data->session_id == NULL)
 314                 return NULL;
 315
 316         id = os_malloc(data->id_len);
 317         if (id == NULL)
 318                 return NULL;
 319
 320         *len = data->id_len;
 321         os_memcpy(id, data->session_id, data->id_len);
 322
 323         return id;
 324 }
 325
 326
 327 int eap_peer_tls_register(void)
 328 {
 329         struct eap_method *eap;
 330         int ret;
 331
 332         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 333                                     EAP_VENDOR_IETF, EAP_TYPE_TLS, "TLS");
 334         if (eap == NULL)
 335                 return -1;
 336
 337         eap->init = eap_tls_init;
 338         eap->deinit = eap_tls_deinit;
 339         eap->process = eap_tls_process;
 340         eap->isKeyAvailable = eap_tls_isKeyAvailable;
 341         eap->getKey = eap_tls_getKey;
 342         eap->getSessionId = eap_tls_get_session_id;
 343         eap->get_status = eap_tls_get_status;
 344         eap->has_reauth_data = eap_tls_has_reauth_data;
 345         eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
 346         eap->init_for_reauth = eap_tls_init_for_reauth;
 347         eap->get_emsk = eap_tls_get_emsk;
 348
 349         ret = eap_peer_method_register(eap);
 350         if (ret)
 351                 eap_peer_method_free(eap);
 352         return ret;
 353 }
 354
 355
 356 #ifdef EAP_UNAUTH_TLS
 357 int eap_peer_unauth_tls_register(void)
 358 {
 359         struct eap_method *eap;
 360         int ret;
 361
 362         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 363                                     EAP_VENDOR_UNAUTH_TLS,
 364                                     EAP_VENDOR_TYPE_UNAUTH_TLS, "UNAUTH-TLS");
 365         if (eap == NULL)
 366                 return -1;
 367
 368         eap->init = eap_unauth_tls_init;
 369         eap->deinit = eap_tls_deinit;
 370         eap->process = eap_tls_process;
 371         eap->isKeyAvailable = eap_tls_isKeyAvailable;
 372         eap->getKey = eap_tls_getKey;
 373         eap->get_status = eap_tls_get_status;
 374         eap->has_reauth_data = eap_tls_has_reauth_data;
 375         eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
 376         eap->init_for_reauth = eap_tls_init_for_reauth;
 377         eap->get_emsk = eap_tls_get_emsk;
 378
 379         ret = eap_peer_method_register(eap);
 380         if (ret)
 381                 eap_peer_method_free(eap);
 382         return ret;
 383 }
 384 #endif /* EAP_UNAUTH_TLS */