dist/wpa/src/eap_peer/eap_tls.c

   1 /*
   2  * EAP peer method: EAP-TLS (RFC 2716)
   3  * Copyright (c) 2004-2008, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "eap_i.h"
  19 #include "eap_tls_common.h"
  20 #include "eap_config.h"
  21 #include "tls.h"
  22
  23
  24 static void eap_tls_deinit(struct eap_sm *sm, void *priv);
  25
  26
  27 struct eap_tls_data {
  28         struct eap_ssl_data ssl;
  29         u8 *key_data;
  30 };
  31
  32
  33 static void * eap_tls_init(struct eap_sm *sm)
  34 {
  35         struct eap_tls_data *data;
  36         struct eap_peer_config *config = eap_get_config(sm);
  37         if (config == NULL ||
  38             ((sm->init_phase2 ? config->private_key2 : config->private_key)
  39             == NULL && config->engine == 0)) {
  40                 wpa_printf(MSG_INFO, "EAP-TLS: Private key not configured");
  41                 return NULL;
  42         }
  43
  44         data = os_zalloc(sizeof(*data));
  45         if (data == NULL)
  46                 return NULL;
  47
  48         if (eap_peer_tls_ssl_init(sm, &data->ssl, config)) {
  49                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to initialize SSL.");
  50                 eap_tls_deinit(sm, data);
  51                 if (config->engine) {
  52                         wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting Smartcard "
  53                                    "PIN");
  54                         eap_sm_request_pin(sm);
  55                         sm->ignore = TRUE;
  56                 } else if (config->private_key && !config->private_key_passwd)
  57                 {
  58                         wpa_printf(MSG_DEBUG, "EAP-TLS: Requesting private "
  59                                    "key passphrase");
  60                         eap_sm_request_passphrase(sm);
  61                         sm->ignore = TRUE;
  62                 }
  63                 return NULL;
  64         }
  65
  66         return data;
  67 }
  68
  69
  70 static void eap_tls_deinit(struct eap_sm *sm, void *priv)
  71 {
  72         struct eap_tls_data *data = priv;
  73         if (data == NULL)
  74                 return;
  75         eap_peer_tls_ssl_deinit(sm, &data->ssl);
  76         os_free(data->key_data);
  77         os_free(data);
  78 }
  79
  80
  81 static struct wpabuf * eap_tls_failure(struct eap_sm *sm,
  82                                        struct eap_tls_data *data,
  83                                        struct eap_method_ret *ret, int res,
  84                                        struct wpabuf *resp, u8 id)
  85 {
  86         wpa_printf(MSG_DEBUG, "EAP-TLS: TLS processing failed");
  87
  88         ret->methodState = METHOD_DONE;
  89         ret->decision = DECISION_FAIL;
  90
  91         if (res == -1) {
  92                 struct eap_peer_config *config = eap_get_config(sm);
  93                 if (config) {
  94                         /*
  95                          * The TLS handshake failed. So better forget the old
  96                          * PIN. It may be wrong, we cannot be sure but trying
  97                          * the wrong one again might block it on the card--so
  98                          * better ask the user again.
  99                          */
 100                         os_free(config->pin);
 101                         config->pin = NULL;
 102                 }
 103         }
 104
 105         if (resp) {
 106                 /*
 107                  * This is likely an alert message, so send it instead of just
 108                  * ACKing the error.
 109                  */
 110                 return resp;
 111         }
 112
 113         return eap_peer_tls_build_ack(id, EAP_TYPE_TLS, 0);
 114 }
 115
 116
 117 static void eap_tls_success(struct eap_sm *sm, struct eap_tls_data *data,
 118                             struct eap_method_ret *ret)
 119 {
 120         wpa_printf(MSG_DEBUG, "EAP-TLS: Done");
 121
 122         ret->methodState = METHOD_DONE;
 123         ret->decision = DECISION_UNCOND_SUCC;
 124
 125         os_free(data->key_data);
 126         data->key_data = eap_peer_tls_derive_key(sm, &data->ssl,
 127                                                  "client EAP encryption",
 128                                                  EAP_TLS_KEY_LEN +
 129                                                  EAP_EMSK_LEN);
 130         if (data->key_data) {
 131                 wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived key",
 132                                 data->key_data, EAP_TLS_KEY_LEN);
 133                 wpa_hexdump_key(MSG_DEBUG, "EAP-TLS: Derived EMSK",
 134                                 data->key_data + EAP_TLS_KEY_LEN,
 135                                 EAP_EMSK_LEN);
 136         } else {
 137                 wpa_printf(MSG_INFO, "EAP-TLS: Failed to derive key");
 138         }
 139 }
 140
 141
 142 static struct wpabuf * eap_tls_process(struct eap_sm *sm, void *priv,
 143                                        struct eap_method_ret *ret,
 144                                        const struct wpabuf *reqData)
 145 {
 146         size_t left;
 147         int res;
 148         struct wpabuf *resp;
 149         u8 flags, id;
 150         const u8 *pos;
 151         struct eap_tls_data *data = priv;
 152
 153         pos = eap_peer_tls_process_init(sm, &data->ssl, EAP_TYPE_TLS, ret,
 154                                         reqData, &left, &flags);
 155         if (pos == NULL)
 156                 return NULL;
 157         id = eap_get_id(reqData);
 158
 159         if (flags & EAP_TLS_FLAGS_START) {
 160                 wpa_printf(MSG_DEBUG, "EAP-TLS: Start");
 161                 left = 0; /* make sure that this frame is empty, even though it
 162                            * should always be, anyway */
 163         }
 164
 165         resp = NULL;
 166         res = eap_peer_tls_process_helper(sm, &data->ssl, EAP_TYPE_TLS, 0, id,
 167                                           pos, left, &resp);
 168
 169         if (res < 0) {
 170                 return eap_tls_failure(sm, data, ret, res, resp, id);
 171         }
 172
 173         if (tls_connection_established(sm->ssl_ctx, data->ssl.conn))
 174                 eap_tls_success(sm, data, ret);
 175
 176         if (res == 1) {
 177                 wpabuf_free(resp);
 178                 return eap_peer_tls_build_ack(id, EAP_TYPE_TLS, 0);
 179         }
 180
 181         return resp;
 182 }
 183
 184
 185 static Boolean eap_tls_has_reauth_data(struct eap_sm *sm, void *priv)
 186 {
 187         struct eap_tls_data *data = priv;
 188         return tls_connection_established(sm->ssl_ctx, data->ssl.conn);
 189 }
 190
 191
 192 static void eap_tls_deinit_for_reauth(struct eap_sm *sm, void *priv)
 193 {
 194 }
 195
 196
 197 static void * eap_tls_init_for_reauth(struct eap_sm *sm, void *priv)
 198 {
 199         struct eap_tls_data *data = priv;
 200         os_free(data->key_data);
 201         data->key_data = NULL;
 202         if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
 203                 os_free(data);
 204                 return NULL;
 205         }
 206         return priv;
 207 }
 208
 209
 210 static int eap_tls_get_status(struct eap_sm *sm, void *priv, char *buf,
 211                               size_t buflen, int verbose)
 212 {
 213         struct eap_tls_data *data = priv;
 214         return eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
 215 }
 216
 217
 218 static Boolean eap_tls_isKeyAvailable(struct eap_sm *sm, void *priv)
 219 {
 220         struct eap_tls_data *data = priv;
 221         return data->key_data != NULL;
 222 }
 223
 224
 225 static u8 * eap_tls_getKey(struct eap_sm *sm, void *priv, size_t *len)
 226 {
 227         struct eap_tls_data *data = priv;
 228         u8 *key;
 229
 230         if (data->key_data == NULL)
 231                 return NULL;
 232
 233         key = os_malloc(EAP_TLS_KEY_LEN);
 234         if (key == NULL)
 235                 return NULL;
 236
 237         *len = EAP_TLS_KEY_LEN;
 238         os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
 239
 240         return key;
 241 }
 242
 243
 244 static u8 * eap_tls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
 245 {
 246         struct eap_tls_data *data = priv;
 247         u8 *key;
 248
 249         if (data->key_data == NULL)
 250                 return NULL;
 251
 252         key = os_malloc(EAP_EMSK_LEN);
 253         if (key == NULL)
 254                 return NULL;
 255
 256         *len = EAP_EMSK_LEN;
 257         os_memcpy(key, data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
 258
 259         return key;
 260 }
 261
 262
 263 int eap_peer_tls_register(void)
 264 {
 265         struct eap_method *eap;
 266         int ret;
 267
 268         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 269                                     EAP_VENDOR_IETF, EAP_TYPE_TLS, "TLS");
 270         if (eap == NULL)
 271                 return -1;
 272
 273         eap->init = eap_tls_init;
 274         eap->deinit = eap_tls_deinit;
 275         eap->process = eap_tls_process;
 276         eap->isKeyAvailable = eap_tls_isKeyAvailable;
 277         eap->getKey = eap_tls_getKey;
 278         eap->get_status = eap_tls_get_status;
 279         eap->has_reauth_data = eap_tls_has_reauth_data;
 280         eap->deinit_for_reauth = eap_tls_deinit_for_reauth;
 281         eap->init_for_reauth = eap_tls_init_for_reauth;
 282         eap->get_emsk = eap_tls_get_emsk;
 283
 284         ret = eap_peer_method_register(eap);
 285         if (ret)
 286                 eap_peer_method_free(eap);
 287         return ret;
 288 }