src/eap_peer/eap_i.h

   1 /*
   2  * EAP peer state machines internal structures (RFC 4137)
   3  * Copyright (c) 2004-2007, 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 #ifndef EAP_I_H
  16 #define EAP_I_H
  17
  18 #include "wpabuf.h"
  19 #include "eap_peer/eap.h"
  20 #include "eap_common/eap_common.h"
  21
  22 /* RFC 4137 - EAP Peer state machine */
  23
  24 typedef enum {
  25         DECISION_FAIL, DECISION_COND_SUCC, DECISION_UNCOND_SUCC
  26 } EapDecision;
  27
  28 typedef enum {
  29         METHOD_NONE, METHOD_INIT, METHOD_CONT, METHOD_MAY_CONT, METHOD_DONE
  30 } EapMethodState;
  31
  32 /**
  33  * struct eap_method_ret - EAP return values from struct eap_method::process()
  34  *
  35  * These structure contains OUT variables for the interface between peer state
  36  * machine and methods (RFC 4137, Sect. 4.2). eapRespData will be returned as
  37  * the return value of struct eap_method::process() so it is not included in
  38  * this structure.
  39  */
  40 struct eap_method_ret {
  41         /**
  42          * ignore - Whether method decided to drop the current packed (OUT)
  43          */
  44         Boolean ignore;
  45
  46         /**
  47          * methodState - Method-specific state (IN/OUT)
  48          */
  49         EapMethodState methodState;
  50
  51         /**
  52          * decision - Authentication decision (OUT)
  53          */
  54         EapDecision decision;
  55
  56         /**
  57          * allowNotifications - Whether method allows notifications (OUT)
  58          */
  59         Boolean allowNotifications;
  60 };
  61
  62
  63 /**
  64  * struct eap_method - EAP method interface
  65  * This structure defines the EAP method interface. Each method will need to
  66  * register its own EAP type, EAP name, and set of function pointers for method
  67  * specific operations. This interface is based on section 4.4 of RFC 4137.
  68  */
  69 struct eap_method {
  70         /**
  71          * vendor - EAP Vendor-ID (EAP_VENDOR_*) (0 = IETF)
  72          */
  73         int vendor;
  74
  75         /**
  76          * method - EAP type number (EAP_TYPE_*)
  77          */
  78         EapType method;
  79
  80         /**
  81          * name - Name of the method (e.g., "TLS")
  82          */
  83         const char *name;
  84
  85         /**
  86          * init - Initialize an EAP method
  87          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
  88          * Returns: Pointer to allocated private data, or %NULL on failure
  89          *
  90          * This function is used to initialize the EAP method explicitly
  91          * instead of using METHOD_INIT state as specific in RFC 4137. The
  92          * method is expected to initialize it method-specific state and return
  93          * a pointer that will be used as the priv argument to other calls.
  94          */
  95         void * (*init)(struct eap_sm *sm);
  96
  97         /**
  98          * deinit - Deinitialize an EAP method
  99          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 100          * @priv: Pointer to private EAP method data from eap_method::init()
 101          *
 102          * Deinitialize the EAP method and free any allocated private data.
 103          */
 104         void (*deinit)(struct eap_sm *sm, void *priv);
 105
 106         /**
 107          * process - Process an EAP request
 108          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 109          * @priv: Pointer to private EAP method data from eap_method::init()
 110          * @ret: Return values from EAP request validation and processing
 111          * @reqData: EAP request to be processed (eapReqData)
 112          * Returns: Pointer to allocated EAP response packet (eapRespData)
 113          *
 114          * This function is a combination of m.check(), m.process(), and
 115          * m.buildResp() procedures defined in section 4.4 of RFC 4137 In other
 116          * words, this function validates the incoming request, processes it,
 117          * and build a response packet. m.check() and m.process() return values
 118          * are returned through struct eap_method_ret *ret variable. Caller is
 119          * responsible for freeing the returned EAP response packet.
 120          */
 121         struct wpabuf * (*process)(struct eap_sm *sm, void *priv,
 122                                    struct eap_method_ret *ret,
 123                                    const struct wpabuf *reqData);
 124
 125         /**
 126          * isKeyAvailable - Find out whether EAP method has keying material
 127          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 128          * @priv: Pointer to private EAP method data from eap_method::init()
 129          * Returns: %TRUE if key material (eapKeyData) is available
 130          */
 131         Boolean (*isKeyAvailable)(struct eap_sm *sm, void *priv);
 132
 133         /**
 134          * getKey - Get EAP method specific keying material (eapKeyData)
 135          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 136          * @priv: Pointer to private EAP method data from eap_method::init()
 137          * @len: Pointer to variable to store key length (eapKeyDataLen)
 138          * Returns: Keying material (eapKeyData) or %NULL if not available
 139          *
 140          * This function can be used to get the keying material from the EAP
 141          * method. The key may already be stored in the method-specific private
 142          * data or this function may derive the key.
 143          */
 144         u8 * (*getKey)(struct eap_sm *sm, void *priv, size_t *len);
 145
 146         /**
 147          * get_status - Get EAP method status
 148          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 149          * @priv: Pointer to private EAP method data from eap_method::init()
 150          * @buf: Buffer for status information
 151          * @buflen: Maximum buffer length
 152          * @verbose: Whether to include verbose status information
 153          * Returns: Number of bytes written to buf
 154          *
 155          * Query EAP method for status information. This function fills in a
 156          * text area with current status information from the EAP method. If
 157          * the buffer (buf) is not large enough, status information will be
 158          * truncated to fit the buffer.
 159          */
 160         int (*get_status)(struct eap_sm *sm, void *priv, char *buf,
 161                           size_t buflen, int verbose);
 162
 163         /**
 164          * has_reauth_data - Whether method is ready for fast reauthentication
 165          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 166          * @priv: Pointer to private EAP method data from eap_method::init()
 167          * Returns: %TRUE or %FALSE based on whether fast reauthentication is
 168          * possible
 169          *
 170          * This function is an optional handler that only EAP methods
 171          * supporting fast re-authentication need to implement.
 172          */
 173         Boolean (*has_reauth_data)(struct eap_sm *sm, void *priv);
 174
 175         /**
 176          * deinit_for_reauth - Release data that is not needed for fast re-auth
 177          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 178          * @priv: Pointer to private EAP method data from eap_method::init()
 179          *
 180          * This function is an optional handler that only EAP methods
 181          * supporting fast re-authentication need to implement. This is called
 182          * when authentication has been completed and EAP state machine is
 183          * requesting that enough state information is maintained for fast
 184          * re-authentication
 185          */
 186         void (*deinit_for_reauth)(struct eap_sm *sm, void *priv);
 187
 188         /**
 189          * init_for_reauth - Prepare for start of fast re-authentication
 190          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 191          * @priv: Pointer to private EAP method data from eap_method::init()
 192          *
 193          * This function is an optional handler that only EAP methods
 194          * supporting fast re-authentication need to implement. This is called
 195          * when EAP authentication is started and EAP state machine is
 196          * requesting fast re-authentication to be used.
 197          */
 198         void * (*init_for_reauth)(struct eap_sm *sm, void *priv);
 199
 200         /**
 201          * get_identity - Get method specific identity for re-authentication
 202          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 203          * @priv: Pointer to private EAP method data from eap_method::init()
 204          * @len: Length of the returned identity
 205          * Returns: Pointer to the method specific identity or %NULL if default
 206          * identity is to be used
 207          *
 208          * This function is an optional handler that only EAP methods
 209          * that use method specific identity need to implement.
 210          */
 211         const u8 * (*get_identity)(struct eap_sm *sm, void *priv, size_t *len);
 212
 213         /**
 214          * free - Free EAP method data
 215          * @method: Pointer to the method data registered with
 216          * eap_peer_method_register().
 217          *
 218          * This function will be called when the EAP method is being
 219          * unregistered. If the EAP method allocated resources during
 220          * registration (e.g., allocated struct eap_method), they should be
 221          * freed in this function. No other method functions will be called
 222          * after this call. If this function is not defined (i.e., function
 223          * pointer is %NULL), a default handler is used to release the method
 224          * data with free(method). This is suitable for most cases.
 225          */
 226         void (*free)(struct eap_method *method);
 227
 228 #define EAP_PEER_METHOD_INTERFACE_VERSION 1
 229         /**
 230          * version - Version of the EAP peer method interface
 231          *
 232          * The EAP peer method implementation should set this variable to
 233          * EAP_PEER_METHOD_INTERFACE_VERSION. This is used to verify that the
 234          * EAP method is using supported API version when using dynamically
 235          * loadable EAP methods.
 236          */
 237         int version;
 238
 239         /**
 240          * next - Pointer to the next EAP method
 241          *
 242          * This variable is used internally in the EAP method registration code
 243          * to create a linked list of registered EAP methods.
 244          */
 245         struct eap_method *next;
 246
 247 #ifdef CONFIG_DYNAMIC_EAP_METHODS
 248         /**
 249          * dl_handle - Handle for the dynamic library
 250          *
 251          * This variable is used internally in the EAP method registration code
 252          * to store a handle for the dynamic library. If the method is linked
 253          * in statically, this is %NULL.
 254          */
 255         void *dl_handle;
 256 #endif /* CONFIG_DYNAMIC_EAP_METHODS */
 257
 258         /**
 259          * get_emsk - Get EAP method specific keying extended material (EMSK)
 260          * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
 261          * @priv: Pointer to private EAP method data from eap_method::init()
 262          * @len: Pointer to a variable to store EMSK length
 263          * Returns: EMSK or %NULL if not available
 264          *
 265          * This function can be used to get the extended keying material from
 266          * the EAP method. The key may already be stored in the method-specific
 267          * private data or this function may derive the key.
 268          */
 269         u8 * (*get_emsk)(struct eap_sm *sm, void *priv, size_t *len);
 270 };
 271
 272
 273 /**
 274  * struct eap_sm - EAP state machine data
 275  */
 276 struct eap_sm {
 277         enum {
 278                 EAP_INITIALIZE, EAP_DISABLED, EAP_IDLE, EAP_RECEIVED,
 279                 EAP_GET_METHOD, EAP_METHOD, EAP_SEND_RESPONSE, EAP_DISCARD,
 280                 EAP_IDENTITY, EAP_NOTIFICATION, EAP_RETRANSMIT, EAP_SUCCESS,
 281                 EAP_FAILURE
 282         } EAP_state;
 283         /* Long-term local variables */
 284         EapType selectedMethod;
 285         EapMethodState methodState;
 286         int lastId;
 287         struct wpabuf *lastRespData;
 288         EapDecision decision;
 289         /* Short-term local variables */
 290         Boolean rxReq;
 291         Boolean rxSuccess;
 292         Boolean rxFailure;
 293         int reqId;
 294         EapType reqMethod;
 295         int reqVendor;
 296         u32 reqVendorMethod;
 297         Boolean ignore;
 298         /* Constants */
 299         int ClientTimeout;
 300
 301         /* Miscellaneous variables */
 302         Boolean allowNotifications; /* peer state machine <-> methods */
 303         struct wpabuf *eapRespData; /* peer to lower layer */
 304         Boolean eapKeyAvailable; /* peer to lower layer */
 305         u8 *eapKeyData; /* peer to lower layer */
 306         size_t eapKeyDataLen; /* peer to lower layer */
 307         const struct eap_method *m; /* selected EAP method */
 308         /* not defined in RFC 4137 */
 309         Boolean changed;
 310         void *eapol_ctx;
 311         struct eapol_callbacks *eapol_cb;
 312         void *eap_method_priv;
 313         int init_phase2;
 314         int fast_reauth;
 315
 316         Boolean rxResp /* LEAP only */;
 317         Boolean leap_done;
 318         Boolean peap_done;
 319         u8 req_md5[16]; /* MD5() of the current EAP packet */
 320         u8 last_md5[16]; /* MD5() of the previously received EAP packet; used
 321                           * in duplicate request detection. */
 322
 323         void *msg_ctx;
 324         void *scard_ctx;
 325         void *ssl_ctx;
 326
 327         unsigned int workaround;
 328
 329         /* Optional challenges generated in Phase 1 (EAP-FAST) */
 330         u8 *peer_challenge, *auth_challenge;
 331
 332         int num_rounds;
 333         int force_disabled;
 334
 335         struct wps_context *wps;
 336
 337         int prev_failure;
 338 };
 339
 340 const u8 * eap_get_config_identity(struct eap_sm *sm, size_t *len);
 341 const u8 * eap_get_config_password(struct eap_sm *sm, size_t *len);
 342 const u8 * eap_get_config_password2(struct eap_sm *sm, size_t *len, int *hash);
 343 const u8 * eap_get_config_new_password(struct eap_sm *sm, size_t *len);
 344 const u8 * eap_get_config_otp(struct eap_sm *sm, size_t *len);
 345 void eap_clear_config_otp(struct eap_sm *sm);
 346 const char * eap_get_config_phase1(struct eap_sm *sm);
 347 const char * eap_get_config_phase2(struct eap_sm *sm);
 348 int eap_get_config_fragment_size(struct eap_sm *sm);
 349 struct eap_peer_config * eap_get_config(struct eap_sm *sm);
 350 void eap_set_config_blob(struct eap_sm *sm, struct wpa_config_blob *blob);
 351 const struct wpa_config_blob *
 352 eap_get_config_blob(struct eap_sm *sm, const char *name);
 353 void eap_notify_pending(struct eap_sm *sm);
 354 int eap_allowed_method(struct eap_sm *sm, int vendor, u32 method);
 355
 356 #endif /* EAP_I_H */