1 /* 2 * EAP peer state machines internal structures (RFC 4137) 3 * Copyright (c) 2004-2007, 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 #ifndef EAP_I_H 10 #define EAP_I_H 11 12 #include "wpabuf.h" 13 #include "eap_peer/eap.h" 14 #include "eap_common/eap_common.h" 15 16 /* RFC 4137 - EAP Peer state machine */ 17 18 typedef enum { 19 DECISION_FAIL, DECISION_COND_SUCC, DECISION_UNCOND_SUCC 20 } EapDecision; 21 22 typedef enum { 23 METHOD_NONE, METHOD_INIT, METHOD_CONT, METHOD_MAY_CONT, METHOD_DONE 24 } EapMethodState; 25 26 /** 27 * struct eap_method_ret - EAP return values from struct eap_method::process() 28 * 29 * These structure contains OUT variables for the interface between peer state 30 * machine and methods (RFC 4137, Sect. 4.2). eapRespData will be returned as 31 * the return value of struct eap_method::process() so it is not included in 32 * this structure. 33 */ 34 struct eap_method_ret { 35 /** 36 * ignore - Whether method decided to drop the current packed (OUT) 37 */ 38 Boolean ignore; 39 40 /** 41 * methodState - Method-specific state (IN/OUT) 42 */ 43 EapMethodState methodState; 44 45 /** 46 * decision - Authentication decision (OUT) 47 */ 48 EapDecision decision; 49 50 /** 51 * allowNotifications - Whether method allows notifications (OUT) 52 */ 53 Boolean allowNotifications; 54 }; 55 56 57 /** 58 * struct eap_method - EAP method interface 59 * This structure defines the EAP method interface. Each method will need to 60 * register its own EAP type, EAP name, and set of function pointers for method 61 * specific operations. This interface is based on section 4.4 of RFC 4137. 62 */ 63 struct eap_method { 64 /** 65 * vendor - EAP Vendor-ID (EAP_VENDOR_*) (0 = IETF) 66 */ 67 int vendor; 68 69 /** 70 * method - EAP type number (EAP_TYPE_*) 71 */ 72 EapType method; 73 74 /** 75 * name - Name of the method (e.g., "TLS") 76 */ 77 const char *name; 78 79 /** 80 * init - Initialize an EAP method 81 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 82 * Returns: Pointer to allocated private data, or %NULL on failure 83 * 84 * This function is used to initialize the EAP method explicitly 85 * instead of using METHOD_INIT state as specific in RFC 4137. The 86 * method is expected to initialize it method-specific state and return 87 * a pointer that will be used as the priv argument to other calls. 88 */ 89 void * (*init)(struct eap_sm *sm); 90 91 /** 92 * deinit - Deinitialize an EAP method 93 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 94 * @priv: Pointer to private EAP method data from eap_method::init() 95 * 96 * Deinitialize the EAP method and free any allocated private data. 97 */ 98 void (*deinit)(struct eap_sm *sm, void *priv); 99 100 /** 101 * process - Process an EAP request 102 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 103 * @priv: Pointer to private EAP method data from eap_method::init() 104 * @ret: Return values from EAP request validation and processing 105 * @reqData: EAP request to be processed (eapReqData) 106 * Returns: Pointer to allocated EAP response packet (eapRespData) 107 * 108 * This function is a combination of m.check(), m.process(), and 109 * m.buildResp() procedures defined in section 4.4 of RFC 4137 In other 110 * words, this function validates the incoming request, processes it, 111 * and build a response packet. m.check() and m.process() return values 112 * are returned through struct eap_method_ret *ret variable. Caller is 113 * responsible for freeing the returned EAP response packet. 114 */ 115 struct wpabuf * (*process)(struct eap_sm *sm, void *priv, 116 struct eap_method_ret *ret, 117 const struct wpabuf *reqData); 118 119 /** 120 * isKeyAvailable - Find out whether EAP method has keying material 121 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 122 * @priv: Pointer to private EAP method data from eap_method::init() 123 * Returns: %TRUE if key material (eapKeyData) is available 124 */ 125 Boolean (*isKeyAvailable)(struct eap_sm *sm, void *priv); 126 127 /** 128 * getKey - Get EAP method specific keying material (eapKeyData) 129 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 130 * @priv: Pointer to private EAP method data from eap_method::init() 131 * @len: Pointer to variable to store key length (eapKeyDataLen) 132 * Returns: Keying material (eapKeyData) or %NULL if not available 133 * 134 * This function can be used to get the keying material from the EAP 135 * method. The key may already be stored in the method-specific private 136 * data or this function may derive the key. 137 */ 138 u8 * (*getKey)(struct eap_sm *sm, void *priv, size_t *len); 139 140 /** 141 * get_status - Get EAP method status 142 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 143 * @priv: Pointer to private EAP method data from eap_method::init() 144 * @buf: Buffer for status information 145 * @buflen: Maximum buffer length 146 * @verbose: Whether to include verbose status information 147 * Returns: Number of bytes written to buf 148 * 149 * Query EAP method for status information. This function fills in a 150 * text area with current status information from the EAP method. If 151 * the buffer (buf) is not large enough, status information will be 152 * truncated to fit the buffer. 153 */ 154 int (*get_status)(struct eap_sm *sm, void *priv, char *buf, 155 size_t buflen, int verbose); 156 157 /** 158 * has_reauth_data - Whether method is ready for fast reauthentication 159 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 160 * @priv: Pointer to private EAP method data from eap_method::init() 161 * Returns: %TRUE or %FALSE based on whether fast reauthentication is 162 * possible 163 * 164 * This function is an optional handler that only EAP methods 165 * supporting fast re-authentication need to implement. 166 */ 167 Boolean (*has_reauth_data)(struct eap_sm *sm, void *priv); 168 169 /** 170 * deinit_for_reauth - Release data that is not needed for fast re-auth 171 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 172 * @priv: Pointer to private EAP method data from eap_method::init() 173 * 174 * This function is an optional handler that only EAP methods 175 * supporting fast re-authentication need to implement. This is called 176 * when authentication has been completed and EAP state machine is 177 * requesting that enough state information is maintained for fast 178 * re-authentication 179 */ 180 void (*deinit_for_reauth)(struct eap_sm *sm, void *priv); 181 182 /** 183 * init_for_reauth - Prepare for start of fast re-authentication 184 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 185 * @priv: Pointer to private EAP method data from eap_method::init() 186 * 187 * This function is an optional handler that only EAP methods 188 * supporting fast re-authentication need to implement. This is called 189 * when EAP authentication is started and EAP state machine is 190 * requesting fast re-authentication to be used. 191 */ 192 void * (*init_for_reauth)(struct eap_sm *sm, void *priv); 193 194 /** 195 * get_identity - Get method specific identity for re-authentication 196 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 197 * @priv: Pointer to private EAP method data from eap_method::init() 198 * @len: Length of the returned identity 199 * Returns: Pointer to the method specific identity or %NULL if default 200 * identity is to be used 201 * 202 * This function is an optional handler that only EAP methods 203 * that use method specific identity need to implement. 204 */ 205 const u8 * (*get_identity)(struct eap_sm *sm, void *priv, size_t *len); 206 207 /** 208 * free - Free EAP method data 209 * @method: Pointer to the method data registered with 210 * eap_peer_method_register(). 211 * 212 * This function will be called when the EAP method is being 213 * unregistered. If the EAP method allocated resources during 214 * registration (e.g., allocated struct eap_method), they should be 215 * freed in this function. No other method functions will be called 216 * after this call. If this function is not defined (i.e., function 217 * pointer is %NULL), a default handler is used to release the method 218 * data with free(method). This is suitable for most cases. 219 */ 220 void (*free)(struct eap_method *method); 221 222 #define EAP_PEER_METHOD_INTERFACE_VERSION 1 223 /** 224 * version - Version of the EAP peer method interface 225 * 226 * The EAP peer method implementation should set this variable to 227 * EAP_PEER_METHOD_INTERFACE_VERSION. This is used to verify that the 228 * EAP method is using supported API version when using dynamically 229 * loadable EAP methods. 230 */ 231 int version; 232 233 /** 234 * next - Pointer to the next EAP method 235 * 236 * This variable is used internally in the EAP method registration code 237 * to create a linked list of registered EAP methods. 238 */ 239 struct eap_method *next; 240 241 #ifdef CONFIG_DYNAMIC_EAP_METHODS 242 /** 243 * dl_handle - Handle for the dynamic library 244 * 245 * This variable is used internally in the EAP method registration code 246 * to store a handle for the dynamic library. If the method is linked 247 * in statically, this is %NULL. 248 */ 249 void *dl_handle; 250 #endif /* CONFIG_DYNAMIC_EAP_METHODS */ 251 252 /** 253 * get_emsk - Get EAP method specific keying extended material (EMSK) 254 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() 255 * @priv: Pointer to private EAP method data from eap_method::init() 256 * @len: Pointer to a variable to store EMSK length 257 * Returns: EMSK or %NULL if not available 258 * 259 * This function can be used to get the extended keying material from 260 * the EAP method. The key may already be stored in the method-specific 261 * private data or this function may derive the key. 262 */ 263 u8 * (*get_emsk)(struct eap_sm *sm, void *priv, size_t *len); 264 }; 265 266 267 /** 268 * struct eap_sm - EAP state machine data 269 */ 270 struct eap_sm { 271 enum { 272 EAP_INITIALIZE, EAP_DISABLED, EAP_IDLE, EAP_RECEIVED, 273 EAP_GET_METHOD, EAP_METHOD, EAP_SEND_RESPONSE, EAP_DISCARD, 274 EAP_IDENTITY, EAP_NOTIFICATION, EAP_RETRANSMIT, EAP_SUCCESS, 275 EAP_FAILURE 276 } EAP_state; 277 /* Long-term local variables */ 278 EapType selectedMethod; 279 EapMethodState methodState; 280 int lastId; 281 struct wpabuf *lastRespData; 282 EapDecision decision; 283 /* Short-term local variables */ 284 Boolean rxReq; 285 Boolean rxSuccess; 286 Boolean rxFailure; 287 int reqId; 288 EapType reqMethod; 289 int reqVendor; 290 u32 reqVendorMethod; 291 Boolean ignore; 292 /* Constants */ 293 int ClientTimeout; 294 295 /* Miscellaneous variables */ 296 Boolean allowNotifications; /* peer state machine <-> methods */ 297 struct wpabuf *eapRespData; /* peer to lower layer */ 298 Boolean eapKeyAvailable; /* peer to lower layer */ 299 u8 *eapKeyData; /* peer to lower layer */ 300 size_t eapKeyDataLen; /* peer to lower layer */ 301 const struct eap_method *m; /* selected EAP method */ 302 /* not defined in RFC 4137 */ 303 Boolean changed; 304 void *eapol_ctx; 305 struct eapol_callbacks *eapol_cb; 306 void *eap_method_priv; 307 int init_phase2; 308 int fast_reauth; 309 310 Boolean rxResp /* LEAP only */; 311 Boolean leap_done; 312 Boolean peap_done; 313 u8 req_md5[16]; /* MD5() of the current EAP packet */ 314 u8 last_md5[16]; /* MD5() of the previously received EAP packet; used 315 * in duplicate request detection. */ 316 317 void *msg_ctx; 318 void *scard_ctx; 319 void *ssl_ctx; 320 void *ssl_ctx2; 321 322 unsigned int workaround; 323 324 /* Optional challenges generated in Phase 1 (EAP-FAST) */ 325 u8 *peer_challenge, *auth_challenge; 326 327 int num_rounds; 328 int force_disabled; 329 330 struct wps_context *wps; 331 332 int prev_failure; 333 334 struct ext_password_data *ext_pw; 335 struct wpabuf *ext_pw_buf; 336 }; 337 338 const u8 * eap_get_config_identity(struct eap_sm *sm, size_t *len); 339 const u8 * eap_get_config_password(struct eap_sm *sm, size_t *len); 340 const u8 * eap_get_config_password2(struct eap_sm *sm, size_t *len, int *hash); 341 const u8 * eap_get_config_new_password(struct eap_sm *sm, size_t *len); 342 const u8 * eap_get_config_otp(struct eap_sm *sm, size_t *len); 343 void eap_clear_config_otp(struct eap_sm *sm); 344 const char * eap_get_config_phase1(struct eap_sm *sm); 345 const char * eap_get_config_phase2(struct eap_sm *sm); 346 int eap_get_config_fragment_size(struct eap_sm *sm); 347 struct eap_peer_config * eap_get_config(struct eap_sm *sm); 348 void eap_set_config_blob(struct eap_sm *sm, struct wpa_config_blob *blob); 349 const struct wpa_config_blob * 350 eap_get_config_blob(struct eap_sm *sm, const char *name); 351 void eap_notify_pending(struct eap_sm *sm); 352 int eap_allowed_method(struct eap_sm *sm, int vendor, u32 method); 353 354 #endif /* EAP_I_H */ 355