1 /*
2  * hostapd / EAP Authenticator state machine 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_server/eap.h"
14 #include "eap_common/eap_common.h"
15 
16 /* RFC 4137 - EAP Standalone Authenticator */
17 
18 /**
19  * struct eap_method - EAP method interface
20  * This structure defines the EAP method interface. Each method will need to
21  * register its own EAP type, EAP name, and set of function pointers for method
22  * specific operations. This interface is based on section 5.4 of RFC 4137.
23  */
24 struct eap_method {
25 	int vendor;
26 	EapType method;
27 	const char *name;
28 
29 	void * (*init)(struct eap_sm *sm);
30 	void * (*initPickUp)(struct eap_sm *sm);
31 	void (*reset)(struct eap_sm *sm, void *priv);
32 
33 	struct wpabuf * (*buildReq)(struct eap_sm *sm, void *priv, u8 id);
34 	int (*getTimeout)(struct eap_sm *sm, void *priv);
35 	Boolean (*check)(struct eap_sm *sm, void *priv,
36 			 struct wpabuf *respData);
37 	void (*process)(struct eap_sm *sm, void *priv,
38 			struct wpabuf *respData);
39 	Boolean (*isDone)(struct eap_sm *sm, void *priv);
40 	u8 * (*getKey)(struct eap_sm *sm, void *priv, size_t *len);
41 	/* isSuccess is not specified in draft-ietf-eap-statemachine-05.txt,
42 	 * but it is useful in implementing Policy.getDecision() */
43 	Boolean (*isSuccess)(struct eap_sm *sm, void *priv);
44 
45 	/**
46 	 * free - Free EAP method data
47 	 * @method: Pointer to the method data registered with
48 	 * eap_server_method_register().
49 	 *
50 	 * This function will be called when the EAP method is being
51 	 * unregistered. If the EAP method allocated resources during
52 	 * registration (e.g., allocated struct eap_method), they should be
53 	 * freed in this function. No other method functions will be called
54 	 * after this call. If this function is not defined (i.e., function
55 	 * pointer is %NULL), a default handler is used to release the method
56 	 * data with free(method). This is suitable for most cases.
57 	 */
58 	void (*free)(struct eap_method *method);
59 
60 #define EAP_SERVER_METHOD_INTERFACE_VERSION 1
61 	/**
62 	 * version - Version of the EAP server method interface
63 	 *
64 	 * The EAP server method implementation should set this variable to
65 	 * EAP_SERVER_METHOD_INTERFACE_VERSION. This is used to verify that the
66 	 * EAP method is using supported API version when using dynamically
67 	 * loadable EAP methods.
68 	 */
69 	int version;
70 
71 	/**
72 	 * next - Pointer to the next EAP method
73 	 *
74 	 * This variable is used internally in the EAP method registration code
75 	 * to create a linked list of registered EAP methods.
76 	 */
77 	struct eap_method *next;
78 
79 	/**
80 	 * get_emsk - Get EAP method specific keying extended material (EMSK)
81 	 * @sm: Pointer to EAP state machine allocated with eap_sm_init()
82 	 * @priv: Pointer to private EAP method data from eap_method::init()
83 	 * @len: Pointer to a variable to store EMSK length
84 	 * Returns: EMSK or %NULL if not available
85 	 *
86 	 * This function can be used to get the extended keying material from
87 	 * the EAP method. The key may already be stored in the method-specific
88 	 * private data or this function may derive the key.
89 	 */
90 	u8 * (*get_emsk)(struct eap_sm *sm, void *priv, size_t *len);
91 
92 	/**
93 	 * getSessionId - Get EAP method specific Session-Id
94 	 * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
95 	 * @priv: Pointer to private EAP method data from eap_method::init()
96 	 * @len: Pointer to a variable to store Session-Id length
97 	 * Returns: Session-Id or %NULL if not available
98 	 *
99 	 * This function can be used to get the Session-Id from the EAP method.
100 	 * The Session-Id may already be stored in the method-specific private
101 	 * data or this function may derive the Session-Id.
102 	 */
103 	u8 * (*getSessionId)(struct eap_sm *sm, void *priv, size_t *len);
104 };
105 
106 /**
107  * struct eap_sm - EAP server state machine data
108  */
109 struct eap_sm {
110 	enum {
111 		EAP_DISABLED, EAP_INITIALIZE, EAP_IDLE, EAP_RECEIVED,
112 		EAP_INTEGRITY_CHECK, EAP_METHOD_RESPONSE, EAP_METHOD_REQUEST,
113 		EAP_PROPOSE_METHOD, EAP_SELECT_ACTION, EAP_SEND_REQUEST,
114 		EAP_DISCARD, EAP_NAK, EAP_RETRANSMIT, EAP_SUCCESS, EAP_FAILURE,
115 		EAP_TIMEOUT_FAILURE, EAP_PICK_UP_METHOD,
116 		EAP_INITIALIZE_PASSTHROUGH, EAP_IDLE2, EAP_RETRANSMIT2,
117 		EAP_RECEIVED2, EAP_DISCARD2, EAP_SEND_REQUEST2,
118 		EAP_AAA_REQUEST, EAP_AAA_RESPONSE, EAP_AAA_IDLE,
119 		EAP_TIMEOUT_FAILURE2, EAP_FAILURE2, EAP_SUCCESS2,
120 		EAP_INITIATE_REAUTH_START, EAP_INITIATE_RECEIVED
121 	} EAP_state;
122 
123 	/* Constants */
124 	int MaxRetrans;
125 
126 	struct eap_eapol_interface eap_if;
127 
128 	/* Full authenticator state machine local variables */
129 
130 	/* Long-term (maintained between packets) */
131 	EapType currentMethod;
132 	int currentId;
133 	enum {
134 		METHOD_PROPOSED, METHOD_CONTINUE, METHOD_END
135 	} methodState;
136 	int retransCount;
137 	struct wpabuf *lastReqData;
138 	int methodTimeout;
139 
140 	/* Short-term (not maintained between packets) */
141 	Boolean rxResp;
142 	Boolean rxInitiate;
143 	int respId;
144 	EapType respMethod;
145 	int respVendor;
146 	u32 respVendorMethod;
147 	Boolean ignore;
148 	enum {
149 		DECISION_SUCCESS, DECISION_FAILURE, DECISION_CONTINUE,
150 		DECISION_PASSTHROUGH, DECISION_INITIATE_REAUTH_START
151 	} decision;
152 
153 	/* Miscellaneous variables */
154 	const struct eap_method *m; /* selected EAP method */
155 	/* not defined in RFC 4137 */
156 	Boolean changed;
157 	void *eapol_ctx, *msg_ctx;
158 	const struct eapol_callbacks *eapol_cb;
159 	void *eap_method_priv;
160 	u8 *identity;
161 	size_t identity_len;
162 	/* Whether Phase 2 method should validate identity match */
163 	int require_identity_match;
164 	int lastId; /* Identifier used in the last EAP-Packet */
165 	struct eap_user *user;
166 	int user_eap_method_index;
167 	int init_phase2;
168 	void *ssl_ctx;
169 	struct eap_sim_db_data *eap_sim_db_priv;
170 	Boolean backend_auth;
171 	Boolean update_user;
172 	int eap_server;
173 
174 	int num_rounds;
175 	enum {
176 		METHOD_PENDING_NONE, METHOD_PENDING_WAIT, METHOD_PENDING_CONT
177 	} method_pending;
178 
179 	u8 *auth_challenge;
180 	u8 *peer_challenge;
181 
182 	u8 *pac_opaque_encr_key;
183 	u8 *eap_fast_a_id;
184 	size_t eap_fast_a_id_len;
185 	char *eap_fast_a_id_info;
186 	enum {
187 		NO_PROV, ANON_PROV, AUTH_PROV, BOTH_PROV
188 	} eap_fast_prov;
189 	int pac_key_lifetime;
190 	int pac_key_refresh_time;
191 	int eap_sim_aka_result_ind;
192 	int tnc;
193 	u16 pwd_group;
194 	struct wps_context *wps;
195 	struct wpabuf *assoc_wps_ie;
196 	struct wpabuf *assoc_p2p_ie;
197 
198 	Boolean start_reauth;
199 
200 	u8 peer_addr[ETH_ALEN];
201 
202 	/* Fragmentation size for EAP method init() handler */
203 	int fragment_size;
204 
205 	int pbc_in_m1;
206 
207 	const u8 *server_id;
208 	size_t server_id_len;
209 
210 	Boolean initiate_reauth_start_sent;
211 	Boolean try_initiate_reauth;
212 	int erp;
213 	unsigned int tls_session_lifetime;
214 
215 #ifdef CONFIG_TESTING_OPTIONS
216 	u32 tls_test_flags;
217 #endif /* CONFIG_TESTING_OPTIONS */
218 };
219 
220 int eap_user_get(struct eap_sm *sm, const u8 *identity, size_t identity_len,
221 		 int phase2);
222 void eap_log_msg(struct eap_sm *sm, const char *fmt, ...)
223 PRINTF_FORMAT(2, 3);
224 void eap_sm_process_nak(struct eap_sm *sm, const u8 *nak_list, size_t len);
225 
226 #endif /* EAP_I_H */
227