1 /*
2  * hostapd / EAP Full Authenticator state machine (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_H
10 #define EAP_H
11 
12 #include "common/defs.h"
13 #include "utils/list.h"
14 #include "eap_common/eap_defs.h"
15 #include "eap_server/eap_methods.h"
16 #include "wpabuf.h"
17 
18 struct eap_sm;
19 
20 #define EAP_TTLS_AUTH_PAP 1
21 #define EAP_TTLS_AUTH_CHAP 2
22 #define EAP_TTLS_AUTH_MSCHAP 4
23 #define EAP_TTLS_AUTH_MSCHAPV2 8
24 
25 struct eap_user {
26 	struct {
27 		int vendor;
28 		u32 method;
29 	} methods[EAP_MAX_METHODS];
30 	u8 *password;
31 	size_t password_len;
32 	int password_hash; /* whether password is hashed with
33 			    * nt_password_hash() */
34 	u8 *salt;
35 	size_t salt_len;
36 	int phase2;
37 	int force_version;
38 	unsigned int macacl:1;
39 	int ttls_auth; /* bitfield of
40 			* EAP_TTLS_AUTH_{PAP,CHAP,MSCHAP,MSCHAPV2} */
41 	struct hostapd_radius_attr *accept_attr;
42 	u32 t_c_timestamp;
43 };
44 
45 struct eap_eapol_interface {
46 	/* Lower layer to full authenticator variables */
47 	bool eapResp; /* shared with EAPOL Backend Authentication */
48 	struct wpabuf *eapRespData;
49 	bool portEnabled;
50 	int retransWhile;
51 	bool eapRestart; /* shared with EAPOL Authenticator PAE */
52 	int eapSRTT;
53 	int eapRTTVAR;
54 
55 	/* Full authenticator to lower layer variables */
56 	bool eapReq; /* shared with EAPOL Backend Authentication */
57 	bool eapNoReq; /* shared with EAPOL Backend Authentication */
58 	bool eapSuccess;
59 	bool eapFail;
60 	bool eapTimeout;
61 	struct wpabuf *eapReqData;
62 	u8 *eapKeyData;
63 	size_t eapKeyDataLen;
64 	u8 *eapSessionId;
65 	size_t eapSessionIdLen;
66 	bool eapKeyAvailable; /* called keyAvailable in IEEE 802.1X-2004 */
67 
68 	/* AAA interface to full authenticator variables */
69 	bool aaaEapReq;
70 	bool aaaEapNoReq;
71 	bool aaaSuccess;
72 	bool aaaFail;
73 	struct wpabuf *aaaEapReqData;
74 	u8 *aaaEapKeyData;
75 	size_t aaaEapKeyDataLen;
76 	bool aaaEapKeyAvailable;
77 	int aaaMethodTimeout;
78 
79 	/* Full authenticator to AAA interface variables */
80 	bool aaaEapResp;
81 	struct wpabuf *aaaEapRespData;
82 	/* aaaIdentity -> eap_get_identity() */
83 	bool aaaTimeout;
84 };
85 
86 struct eap_server_erp_key {
87 	struct dl_list list;
88 	size_t rRK_len;
89 	size_t rIK_len;
90 	u8 rRK[ERP_MAX_KEY_LEN];
91 	u8 rIK[ERP_MAX_KEY_LEN];
92 	u32 recv_seq;
93 	u8 cryptosuite;
94 	char keyname_nai[];
95 };
96 
97 struct eapol_callbacks {
98 	int (*get_eap_user)(void *ctx, const u8 *identity, size_t identity_len,
99 			    int phase2, struct eap_user *user);
100 	const char * (*get_eap_req_id_text)(void *ctx, size_t *len);
101 	void (*log_msg)(void *ctx, const char *msg);
102 	int (*get_erp_send_reauth_start)(void *ctx);
103 	const char * (*get_erp_domain)(void *ctx);
104 	struct eap_server_erp_key * (*erp_get_key)(void *ctx,
105 						   const char *keyname);
106 	int (*erp_add_key)(void *ctx, struct eap_server_erp_key *erp);
107 };
108 
109 struct eap_config {
110 	/**
111 	 * ssl_ctx - TLS context
112 	 *
113 	 * This is passed to the EAP server implementation as a callback
114 	 * context for TLS operations.
115 	 */
116 	void *ssl_ctx;
117 	void *msg_ctx;
118 
119 	/**
120 	 * eap_sim_db_priv - EAP-SIM/AKA database context
121 	 *
122 	 * This is passed to the EAP-SIM/AKA server implementation as a
123 	 * callback context.
124 	 */
125 	void *eap_sim_db_priv;
126 
127 	struct crypto_rsa_key *imsi_privacy_key;
128 
129 	bool backend_auth;
130 	int eap_server;
131 
132 	/**
133 	 * pwd_group - The D-H group assigned for EAP-pwd
134 	 *
135 	 * If EAP-pwd is not used it can be set to zero.
136 	 */
137 	u16 pwd_group;
138 
139 	/**
140 	 * pac_opaque_encr_key - PAC-Opaque encryption key for EAP-FAST
141 	 *
142 	 * This parameter is used to set a key for EAP-FAST to encrypt the
143 	 * PAC-Opaque data. It can be set to %NULL if EAP-FAST is not used. If
144 	 * set, must point to a 16-octet key.
145 	 */
146 	u8 *pac_opaque_encr_key;
147 
148 	/**
149 	 * eap_fast_a_id - EAP-FAST authority identity (A-ID)
150 	 *
151 	 * If EAP-FAST is not used, this can be set to %NULL. In theory, this
152 	 * is a variable length field, but due to some existing implementations
153 	 * requiring A-ID to be 16 octets in length, it is recommended to use
154 	 * that length for the field to provide interoperability with deployed
155 	 * peer implementations.
156 	 */
157 	u8 *eap_fast_a_id;
158 
159 	/**
160 	 * eap_fast_a_id_len - Length of eap_fast_a_id buffer in octets
161 	 */
162 	size_t eap_fast_a_id_len;
163 	/**
164 	 * eap_fast_a_id_info - EAP-FAST authority identifier information
165 	 *
166 	 * This A-ID-Info contains a user-friendly name for the A-ID. For
167 	 * example, this could be the enterprise and server names in
168 	 * human-readable format. This field is encoded as UTF-8. If EAP-FAST
169 	 * is not used, this can be set to %NULL.
170 	 */
171 	char *eap_fast_a_id_info;
172 
173 	/**
174 	 * eap_fast_prov - EAP-FAST provisioning modes
175 	 *
176 	 * 0 = provisioning disabled, 1 = only anonymous provisioning allowed,
177 	 * 2 = only authenticated provisioning allowed, 3 = both provisioning
178 	 * modes allowed.
179 	 */
180 	enum {
181 		NO_PROV, ANON_PROV, AUTH_PROV, BOTH_PROV
182 	} eap_fast_prov;
183 
184 	/**
185 	 * pac_key_lifetime - EAP-FAST PAC-Key lifetime in seconds
186 	 *
187 	 * This is the hard limit on how long a provisioned PAC-Key can be
188 	 * used.
189 	 */
190 	int pac_key_lifetime;
191 
192 	/**
193 	 * pac_key_refresh_time - EAP-FAST PAC-Key refresh time in seconds
194 	 *
195 	 * This is a soft limit on the PAC-Key. The server will automatically
196 	 * generate a new PAC-Key when this number of seconds (or fewer) of the
197 	 * lifetime remains.
198 	 */
199 	int pac_key_refresh_time;
200 	int eap_teap_auth;
201 	int eap_teap_separate_result;
202 	enum eap_teap_id {
203 		EAP_TEAP_ID_ALLOW_ANY = 0,
204 		EAP_TEAP_ID_REQUIRE_USER = 1,
205 		EAP_TEAP_ID_REQUIRE_MACHINE = 2,
206 		EAP_TEAP_ID_REQUEST_USER_ACCEPT_MACHINE = 3,
207 		EAP_TEAP_ID_REQUEST_MACHINE_ACCEPT_USER = 4,
208 		EAP_TEAP_ID_REQUIRE_USER_AND_MACHINE = 5,
209 	} eap_teap_id;
210 	int eap_teap_method_sequence;
211 
212 	/**
213 	 * eap_sim_aka_result_ind - EAP-SIM/AKA protected success indication
214 	 *
215 	 * This controls whether the protected success/failure indication
216 	 * (AT_RESULT_IND) is used with EAP-SIM and EAP-AKA.
217 	 */
218 	int eap_sim_aka_result_ind;
219 	int eap_sim_id;
220 
221 	/* Maximum number of fast re-authentications allowed after each full
222 	 * EAP-SIM/AKA authentication. */
223 	int eap_sim_aka_fast_reauth_limit;
224 
225 	/**
226 	 * tnc - Trusted Network Connect (TNC)
227 	 *
228 	 * This controls whether TNC is enabled and will be required before the
229 	 * peer is allowed to connect. Note: This is only used with EAP-TTLS
230 	 * and EAP-FAST. If any other EAP method is enabled, the peer will be
231 	 * allowed to connect without TNC.
232 	 */
233 	int tnc;
234 
235 	/**
236 	 * wps - Wi-Fi Protected Setup context
237 	 *
238 	 * If WPS is used with an external RADIUS server (which is quite
239 	 * unlikely configuration), this is used to provide a pointer to WPS
240 	 * context data. Normally, this can be set to %NULL.
241 	 */
242 	struct wps_context *wps;
243 	int fragment_size;
244 
245 	int pbc_in_m1;
246 
247 	/**
248 	 * server_id - Server identity
249 	 */
250 	u8 *server_id;
251 	size_t server_id_len;
252 
253 	/**
254 	 * erp - Whether EAP Re-authentication Protocol (ERP) is enabled
255 	 *
256 	 * This controls whether the authentication server derives ERP key
257 	 * hierarchy (rRK and rIK) from full EAP authentication and allows
258 	 * these keys to be used to perform ERP to derive rMSK instead of full
259 	 * EAP authentication to derive MSK.
260 	 */
261 	int erp;
262 	unsigned int tls_session_lifetime;
263 	unsigned int tls_flags;
264 
265 	unsigned int max_auth_rounds;
266 	unsigned int max_auth_rounds_short;
267 
268 #ifdef CONFIG_TESTING_OPTIONS
269 	bool skip_prot_success;
270 #endif /* CONFIG_TESTING_OPTIONS */
271 };
272 
273 struct eap_session_data {
274 	const struct wpabuf *assoc_wps_ie;
275 	const struct wpabuf *assoc_p2p_ie;
276 	const u8 *peer_addr;
277 #ifdef CONFIG_TESTING_OPTIONS
278 	u32 tls_test_flags;
279 #endif /* CONFIG_TESTING_OPTIONS */
280 };
281 
282 
283 struct eap_sm * eap_server_sm_init(void *eapol_ctx,
284 				   const struct eapol_callbacks *eapol_cb,
285 				   const struct eap_config *conf,
286 				   const struct eap_session_data *sess);
287 void eap_server_sm_deinit(struct eap_sm *sm);
288 int eap_server_sm_step(struct eap_sm *sm);
289 void eap_sm_notify_cached(struct eap_sm *sm);
290 void eap_sm_pending_cb(struct eap_sm *sm);
291 int eap_sm_method_pending(struct eap_sm *sm);
292 const u8 * eap_get_identity(struct eap_sm *sm, size_t *len);
293 const char * eap_get_serial_num(struct eap_sm *sm);
294 const char * eap_get_method(struct eap_sm *sm);
295 const char * eap_get_imsi(struct eap_sm *sm);
296 struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm);
297 void eap_server_clear_identity(struct eap_sm *sm);
298 void eap_server_mschap_rx_callback(struct eap_sm *sm, const char *source,
299 				   const u8 *username, size_t username_len,
300 				   const u8 *challenge, const u8 *response);
301 void eap_erp_update_identity(struct eap_sm *sm, const u8 *eap, size_t len);
302 void eap_user_free(struct eap_user *user);
303 void eap_server_config_free(struct eap_config *cfg);
304 
305 #endif /* EAP_H */
306