eap_i.h revision 346981
1/*
2 * EAP peer state machines internal structures (RFC 4137)
3 * Copyright (c) 2004-2014, 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 "utils/list.h"
14#include "eap_peer/eap.h"
15#include "eap_common/eap_common.h"
16
17#define NO_EAP_METHOD_ERROR (-1)
18
19/* RFC 4137 - EAP Peer state machine */
20
21typedef enum {
22	DECISION_FAIL, DECISION_COND_SUCC, DECISION_UNCOND_SUCC
23} EapDecision;
24
25typedef enum {
26	METHOD_NONE, METHOD_INIT, METHOD_CONT, METHOD_MAY_CONT, METHOD_DONE
27} EapMethodState;
28
29/**
30 * struct eap_method_ret - EAP return values from struct eap_method::process()
31 *
32 * These structure contains OUT variables for the interface between peer state
33 * machine and methods (RFC 4137, Sect. 4.2). eapRespData will be returned as
34 * the return value of struct eap_method::process() so it is not included in
35 * this structure.
36 */
37struct eap_method_ret {
38	/**
39	 * ignore - Whether method decided to drop the current packed (OUT)
40	 */
41	Boolean ignore;
42
43	/**
44	 * methodState - Method-specific state (IN/OUT)
45	 */
46	EapMethodState methodState;
47
48	/**
49	 * decision - Authentication decision (OUT)
50	 */
51	EapDecision decision;
52
53	/**
54	 * allowNotifications - Whether method allows notifications (OUT)
55	 */
56	Boolean allowNotifications;
57};
58
59
60/**
61 * struct eap_method - EAP method interface
62 * This structure defines the EAP method interface. Each method will need to
63 * register its own EAP type, EAP name, and set of function pointers for method
64 * specific operations. This interface is based on section 4.4 of RFC 4137.
65 */
66struct eap_method {
67	/**
68	 * vendor - EAP Vendor-ID (EAP_VENDOR_*) (0 = IETF)
69	 */
70	int vendor;
71
72	/**
73	 * method - EAP type number (EAP_TYPE_*)
74	 */
75	EapType method;
76
77	/**
78	 * name - Name of the method (e.g., "TLS")
79	 */
80	const char *name;
81
82	/**
83	 * init - Initialize an EAP method
84	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
85	 * Returns: Pointer to allocated private data, or %NULL on failure
86	 *
87	 * This function is used to initialize the EAP method explicitly
88	 * instead of using METHOD_INIT state as specific in RFC 4137. The
89	 * method is expected to initialize it method-specific state and return
90	 * a pointer that will be used as the priv argument to other calls.
91	 */
92	void * (*init)(struct eap_sm *sm);
93
94	/**
95	 * deinit - Deinitialize an EAP method
96	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
97	 * @priv: Pointer to private EAP method data from eap_method::init()
98	 *
99	 * Deinitialize the EAP method and free any allocated private data.
100	 */
101	void (*deinit)(struct eap_sm *sm, void *priv);
102
103	/**
104	 * process - Process an EAP request
105	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
106	 * @priv: Pointer to private EAP method data from eap_method::init()
107	 * @ret: Return values from EAP request validation and processing
108	 * @reqData: EAP request to be processed (eapReqData)
109	 * Returns: Pointer to allocated EAP response packet (eapRespData)
110	 *
111	 * This function is a combination of m.check(), m.process(), and
112	 * m.buildResp() procedures defined in section 4.4 of RFC 4137 In other
113	 * words, this function validates the incoming request, processes it,
114	 * and build a response packet. m.check() and m.process() return values
115	 * are returned through struct eap_method_ret *ret variable. Caller is
116	 * responsible for freeing the returned EAP response packet.
117	 */
118	struct wpabuf * (*process)(struct eap_sm *sm, void *priv,
119				   struct eap_method_ret *ret,
120				   const struct wpabuf *reqData);
121
122	/**
123	 * isKeyAvailable - Find out whether EAP method has keying material
124	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
125	 * @priv: Pointer to private EAP method data from eap_method::init()
126	 * Returns: %TRUE if key material (eapKeyData) is available
127	 */
128	Boolean (*isKeyAvailable)(struct eap_sm *sm, void *priv);
129
130	/**
131	 * getKey - Get EAP method specific keying material (eapKeyData)
132	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
133	 * @priv: Pointer to private EAP method data from eap_method::init()
134	 * @len: Pointer to variable to store key length (eapKeyDataLen)
135	 * Returns: Keying material (eapKeyData) or %NULL if not available
136	 *
137	 * This function can be used to get the keying material from the EAP
138	 * method. The key may already be stored in the method-specific private
139	 * data or this function may derive the key.
140	 */
141	u8 * (*getKey)(struct eap_sm *sm, void *priv, size_t *len);
142
143	/**
144	 * get_status - Get EAP method status
145	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
146	 * @priv: Pointer to private EAP method data from eap_method::init()
147	 * @buf: Buffer for status information
148	 * @buflen: Maximum buffer length
149	 * @verbose: Whether to include verbose status information
150	 * Returns: Number of bytes written to buf
151	 *
152	 * Query EAP method for status information. This function fills in a
153	 * text area with current status information from the EAP method. If
154	 * the buffer (buf) is not large enough, status information will be
155	 * truncated to fit the buffer.
156	 */
157	int (*get_status)(struct eap_sm *sm, void *priv, char *buf,
158			  size_t buflen, int verbose);
159
160	/**
161	 * has_reauth_data - Whether method is ready for fast reauthentication
162	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
163	 * @priv: Pointer to private EAP method data from eap_method::init()
164	 * Returns: %TRUE or %FALSE based on whether fast reauthentication is
165	 * possible
166	 *
167	 * This function is an optional handler that only EAP methods
168	 * supporting fast re-authentication need to implement.
169	 */
170	Boolean (*has_reauth_data)(struct eap_sm *sm, void *priv);
171
172	/**
173	 * deinit_for_reauth - Release data that is not needed for fast re-auth
174	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
175	 * @priv: Pointer to private EAP method data from eap_method::init()
176	 *
177	 * This function is an optional handler that only EAP methods
178	 * supporting fast re-authentication need to implement. This is called
179	 * when authentication has been completed and EAP state machine is
180	 * requesting that enough state information is maintained for fast
181	 * re-authentication
182	 */
183	void (*deinit_for_reauth)(struct eap_sm *sm, void *priv);
184
185	/**
186	 * init_for_reauth - Prepare for start of fast re-authentication
187	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
188	 * @priv: Pointer to private EAP method data from eap_method::init()
189	 *
190	 * This function is an optional handler that only EAP methods
191	 * supporting fast re-authentication need to implement. This is called
192	 * when EAP authentication is started and EAP state machine is
193	 * requesting fast re-authentication to be used.
194	 */
195	void * (*init_for_reauth)(struct eap_sm *sm, void *priv);
196
197	/**
198	 * get_identity - Get method specific identity for re-authentication
199	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
200	 * @priv: Pointer to private EAP method data from eap_method::init()
201	 * @len: Length of the returned identity
202	 * Returns: Pointer to the method specific identity or %NULL if default
203	 * identity is to be used
204	 *
205	 * This function is an optional handler that only EAP methods
206	 * that use method specific identity need to implement.
207	 */
208	const u8 * (*get_identity)(struct eap_sm *sm, void *priv, size_t *len);
209
210	/**
211	 * get_error_code - Get the latest EAP method error code
212	 * @priv: Pointer to private EAP method data from eap_method::init()
213	 * Returns: An int for the EAP method specific error code if exists or
214	 * NO_EAP_METHOD_ERROR otherwise.
215	 *
216	 * This method is an optional handler that only EAP methods that need to
217	 * report their error code need to implement.
218	 */
219	int (*get_error_code)(void *priv);
220
221	/**
222	 * free - Free EAP method data
223	 * @method: Pointer to the method data registered with
224	 * eap_peer_method_register().
225	 *
226	 * This function will be called when the EAP method is being
227	 * unregistered. If the EAP method allocated resources during
228	 * registration (e.g., allocated struct eap_method), they should be
229	 * freed in this function. No other method functions will be called
230	 * after this call. If this function is not defined (i.e., function
231	 * pointer is %NULL), a default handler is used to release the method
232	 * data with free(method). This is suitable for most cases.
233	 */
234	void (*free)(struct eap_method *method);
235
236#define EAP_PEER_METHOD_INTERFACE_VERSION 1
237	/**
238	 * version - Version of the EAP peer method interface
239	 *
240	 * The EAP peer method implementation should set this variable to
241	 * EAP_PEER_METHOD_INTERFACE_VERSION. This is used to verify that the
242	 * EAP method is using supported API version when using dynamically
243	 * loadable EAP methods.
244	 */
245	int version;
246
247	/**
248	 * next - Pointer to the next EAP method
249	 *
250	 * This variable is used internally in the EAP method registration code
251	 * to create a linked list of registered EAP methods.
252	 */
253	struct eap_method *next;
254
255#ifdef CONFIG_DYNAMIC_EAP_METHODS
256	/**
257	 * dl_handle - Handle for the dynamic library
258	 *
259	 * This variable is used internally in the EAP method registration code
260	 * to store a handle for the dynamic library. If the method is linked
261	 * in statically, this is %NULL.
262	 */
263	void *dl_handle;
264#endif /* CONFIG_DYNAMIC_EAP_METHODS */
265
266	/**
267	 * get_emsk - Get EAP method specific keying extended material (EMSK)
268	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
269	 * @priv: Pointer to private EAP method data from eap_method::init()
270	 * @len: Pointer to a variable to store EMSK length
271	 * Returns: EMSK or %NULL if not available
272	 *
273	 * This function can be used to get the extended keying material from
274	 * the EAP method. The key may already be stored in the method-specific
275	 * private data or this function may derive the key.
276	 */
277	u8 * (*get_emsk)(struct eap_sm *sm, void *priv, size_t *len);
278
279	/**
280	 * getSessionId - Get EAP method specific Session-Id
281	 * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
282	 * @priv: Pointer to private EAP method data from eap_method::init()
283	 * @len: Pointer to a variable to store Session-Id length
284	 * Returns: Session-Id or %NULL if not available
285	 *
286	 * This function can be used to get the Session-Id from the EAP method.
287	 * The Session-Id may already be stored in the method-specific private
288	 * data or this function may derive the Session-Id.
289	 */
290	u8 * (*getSessionId)(struct eap_sm *sm, void *priv, size_t *len);
291};
292
293
294struct eap_erp_key {
295	struct dl_list list;
296	size_t rRK_len;
297	size_t rIK_len;
298	u8 rRK[ERP_MAX_KEY_LEN];
299	u8 rIK[ERP_MAX_KEY_LEN];
300	u32 next_seq;
301	char keyname_nai[];
302};
303
304/**
305 * struct eap_sm - EAP state machine data
306 */
307struct eap_sm {
308	enum {
309		EAP_INITIALIZE, EAP_DISABLED, EAP_IDLE, EAP_RECEIVED,
310		EAP_GET_METHOD, EAP_METHOD, EAP_SEND_RESPONSE, EAP_DISCARD,
311		EAP_IDENTITY, EAP_NOTIFICATION, EAP_RETRANSMIT, EAP_SUCCESS,
312		EAP_FAILURE
313	} EAP_state;
314	/* Long-term local variables */
315	EapType selectedMethod;
316	EapMethodState methodState;
317	int lastId;
318	struct wpabuf *lastRespData;
319	EapDecision decision;
320	/* Short-term local variables */
321	Boolean rxReq;
322	Boolean rxSuccess;
323	Boolean rxFailure;
324	int reqId;
325	EapType reqMethod;
326	int reqVendor;
327	u32 reqVendorMethod;
328	Boolean ignore;
329	/* Constants */
330	int ClientTimeout;
331
332	/* Miscellaneous variables */
333	Boolean allowNotifications; /* peer state machine <-> methods */
334	struct wpabuf *eapRespData; /* peer to lower layer */
335	Boolean eapKeyAvailable; /* peer to lower layer */
336	u8 *eapKeyData; /* peer to lower layer */
337	size_t eapKeyDataLen; /* peer to lower layer */
338	u8 *eapSessionId; /* peer to lower layer */
339	size_t eapSessionIdLen; /* peer to lower layer */
340	const struct eap_method *m; /* selected EAP method */
341	/* not defined in RFC 4137 */
342	Boolean changed;
343	void *eapol_ctx;
344	const struct eapol_callbacks *eapol_cb;
345	void *eap_method_priv;
346	int init_phase2;
347	int fast_reauth;
348	Boolean reauthInit; /* send EAP-Identity/Re-auth */
349	u32 erp_seq;
350
351	Boolean rxResp /* LEAP only */;
352	Boolean leap_done;
353	Boolean peap_done;
354	u8 req_sha1[20]; /* SHA1() of the current EAP packet */
355	u8 last_sha1[20]; /* SHA1() of the previously received EAP packet; used
356			   * in duplicate request detection. */
357
358	void *msg_ctx;
359	void *scard_ctx;
360	void *ssl_ctx;
361	void *ssl_ctx2;
362
363	unsigned int workaround;
364
365	/* Optional challenges generated in Phase 1 (EAP-FAST) */
366	u8 *peer_challenge, *auth_challenge;
367
368	int num_rounds;
369	int force_disabled;
370
371	struct wps_context *wps;
372
373	int prev_failure;
374	struct eap_peer_config *last_config;
375
376	struct ext_password_data *ext_pw;
377	struct wpabuf *ext_pw_buf;
378
379	int external_sim;
380
381	unsigned int expected_failure:1;
382	unsigned int ext_cert_check:1;
383	unsigned int waiting_ext_cert_check:1;
384
385	struct dl_list erp_keys; /* struct eap_erp_key */
386};
387
388const u8 * eap_get_config_identity(struct eap_sm *sm, size_t *len);
389const u8 * eap_get_config_password(struct eap_sm *sm, size_t *len);
390const u8 * eap_get_config_password2(struct eap_sm *sm, size_t *len, int *hash);
391const u8 * eap_get_config_new_password(struct eap_sm *sm, size_t *len);
392const u8 * eap_get_config_otp(struct eap_sm *sm, size_t *len);
393void eap_clear_config_otp(struct eap_sm *sm);
394const char * eap_get_config_phase1(struct eap_sm *sm);
395const char * eap_get_config_phase2(struct eap_sm *sm);
396int eap_get_config_fragment_size(struct eap_sm *sm);
397struct eap_peer_config * eap_get_config(struct eap_sm *sm);
398void eap_set_config_blob(struct eap_sm *sm, struct wpa_config_blob *blob);
399const struct wpa_config_blob *
400eap_get_config_blob(struct eap_sm *sm, const char *name);
401void eap_notify_pending(struct eap_sm *sm);
402int eap_allowed_method(struct eap_sm *sm, int vendor, u32 method);
403
404#endif /* EAP_I_H */
405