1 /*
2  * eap.h - Extensible Authentication Protocol for PPP (RFC 2284)
3  *
4  * Copyright (c) 2001 by Sun Microsystems, Inc.
5  * All rights reserved.
6  *
7  * Non-exclusive rights to redistribute, modify, translate, and use
8  * this software in source and binary forms, in whole or in part, is
9  * hereby granted, provided that the above copyright notice is
10  * duplicated in any source form, and that neither the name of the
11  * copyright holder nor the author is used to endorse or promote
12  * products derived from this software.
13  *
14  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
16  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17  *
18  * Original version by James Carlson
19  *
20  * $Id: eap.h,v 1.2 2003/06/11 23:56:26 paulus Exp $
21  */
22 
23 #include "netif/ppp/ppp_opts.h"
24 #if PPP_SUPPORT && EAP_SUPPORT  /* don't build if not configured for use in lwipopts.h */
25 
26 #ifndef PPP_EAP_H
27 #define	PPP_EAP_H
28 
29 #include "ppp.h"
30 
31 #ifdef	__cplusplus
32 extern "C" {
33 #endif
34 
35 /*
36  * Packet header = Code, id, length.
37  */
38 #define	EAP_HEADERLEN	4
39 
40 
41 /* EAP message codes. */
42 #define	EAP_REQUEST	1
43 #define	EAP_RESPONSE	2
44 #define	EAP_SUCCESS	3
45 #define	EAP_FAILURE	4
46 
47 /* EAP types */
48 #define	EAPT_IDENTITY		1
49 #define	EAPT_NOTIFICATION	2
50 #define	EAPT_NAK		3	/* (response only) */
51 #define	EAPT_MD5CHAP		4
52 #define	EAPT_OTP		5	/* One-Time Password; RFC 1938 */
53 #define	EAPT_TOKEN		6	/* Generic Token Card */
54 /* 7 and 8 are unassigned. */
55 #define	EAPT_RSA		9	/* RSA Public Key Authentication */
56 #define	EAPT_DSS		10	/* DSS Unilateral */
57 #define	EAPT_KEA		11	/* KEA */
58 #define	EAPT_KEA_VALIDATE	12	/* KEA-VALIDATE	*/
59 #define	EAPT_TLS		13	/* EAP-TLS */
60 #define	EAPT_DEFENDER		14	/* Defender Token (AXENT) */
61 #define	EAPT_W2K		15	/* Windows 2000 EAP */
62 #define	EAPT_ARCOT		16	/* Arcot Systems */
63 #define	EAPT_CISCOWIRELESS	17	/* Cisco Wireless */
64 #define	EAPT_NOKIACARD		18	/* Nokia IP smart card */
65 #define	EAPT_SRP		19	/* Secure Remote Password */
66 /* 20 is deprecated */
67 
68 /* EAP SRP-SHA1 Subtypes */
69 #define	EAPSRP_CHALLENGE	1	/* Request 1 - Challenge */
70 #define	EAPSRP_CKEY		1	/* Response 1 - Client Key */
71 #define	EAPSRP_SKEY		2	/* Request 2 - Server Key */
72 #define	EAPSRP_CVALIDATOR	2	/* Response 2 - Client Validator */
73 #define	EAPSRP_SVALIDATOR	3	/* Request 3 - Server Validator */
74 #define	EAPSRP_ACK		3	/* Response 3 - final ack */
75 #define	EAPSRP_LWRECHALLENGE	4	/* Req/resp 4 - Lightweight rechal */
76 
77 #define	SRPVAL_EBIT	0x00000001	/* Use shared key for ECP */
78 
79 #define	SRP_PSEUDO_ID	"pseudo_"
80 #define	SRP_PSEUDO_LEN	7
81 
82 #define MD5_SIGNATURE_SIZE	16
83 #define EAP_MIN_CHALLENGE_LENGTH	17
84 #define EAP_MAX_CHALLENGE_LENGTH	24
85 #define EAP_MIN_MAX_POWER_OF_TWO_CHALLENGE_LENGTH     3   /* 2^3-1 = 7, 17+7 = 24 */
86 
87 #define	EAP_STATES	\
88 	"Initial", "Pending", "Closed", "Listen", "Identify", \
89 	"SRP1", "SRP2", "SRP3", "MD5Chall", "Open", "SRP4", "BadAuth"
90 
91 #define	eap_client_active(pcb)	((pcb)->eap.es_client.ea_state == eapListen)
92 #if PPP_SERVER
93 #define	eap_server_active(pcb)	\
94 	((pcb)->eap.es_server.ea_state >= eapIdentify && \
95 	 (pcb)->eap.es_server.ea_state <= eapMD5Chall)
96 #endif /* PPP_SERVER */
97 
98 /*
99  * Complete EAP state for one PPP session.
100  */
101 enum eap_state_code {
102 	eapInitial = 0,	/* No EAP authentication yet requested */
103 	eapPending,	/* Waiting for LCP (no timer) */
104 	eapClosed,	/* Authentication not in use */
105 	eapListen,	/* Client ready (and timer running) */
106 	eapIdentify,	/* EAP Identify sent */
107 	eapSRP1,	/* Sent EAP SRP-SHA1 Subtype 1 */
108 	eapSRP2,	/* Sent EAP SRP-SHA1 Subtype 2 */
109 	eapSRP3,	/* Sent EAP SRP-SHA1 Subtype 3 */
110 	eapMD5Chall,	/* Sent MD5-Challenge */
111 	eapOpen,	/* Completed authentication */
112 	eapSRP4,	/* Sent EAP SRP-SHA1 Subtype 4 */
113 	eapBadAuth	/* Failed authentication */
114 };
115 
116 struct eap_auth {
117 	const char *ea_name;	/* Our name */
118 	char ea_peer[MAXNAMELEN +1];	/* Peer's name */
119 	void *ea_session;	/* Authentication library linkage */
120 	u_char *ea_skey;	/* Shared encryption key */
121 	u_short ea_namelen;	/* Length of our name */
122 	u_short ea_peerlen;	/* Length of peer's name */
123 	enum eap_state_code ea_state;
124 	u_char ea_id;		/* Current id */
125 	u_char ea_requests;	/* Number of Requests sent/received */
126 	u_char ea_responses;	/* Number of Responses */
127 	u_char ea_type;		/* One of EAPT_* */
128 	u32_t ea_keyflags;	/* SRP shared key usage flags */
129 };
130 
131 #ifndef EAP_MAX_CHALLENGE_LENGTH
132 #define EAP_MAX_CHALLENGE_LENGTH	24
133 #endif
134 typedef struct eap_state {
135 	struct eap_auth es_client;	/* Client (authenticatee) data */
136 #if PPP_SERVER
137 	struct eap_auth es_server;	/* Server (authenticator) data */
138 #endif /* PPP_SERVER */
139 	int es_savedtime;		/* Saved timeout */
140 	int es_rechallenge;		/* EAP rechallenge interval */
141 	int es_lwrechallenge;		/* SRP lightweight rechallenge inter */
142 	u8_t es_usepseudo;		/* Use SRP Pseudonym if offered one */
143 	int es_usedpseudo;		/* Set if we already sent PN */
144 	int es_challen;			/* Length of challenge string */
145 	u_char es_challenge[EAP_MAX_CHALLENGE_LENGTH];
146 } eap_state;
147 
148 /*
149  * Timeouts.
150  */
151 #if 0 /* moved to ppp_opts.h */
152 #define	EAP_DEFTIMEOUT		3	/* Timeout (seconds) for rexmit */
153 #define	EAP_DEFTRANSMITS	10	/* max # times to transmit */
154 #define	EAP_DEFREQTIME		20	/* Time to wait for peer request */
155 #define	EAP_DEFALLOWREQ		20	/* max # times to accept requests */
156 #endif /* moved to ppp_opts.h */
157 
158 void eap_authwithpeer(ppp_pcb *pcb, const char *localname);
159 void eap_authpeer(ppp_pcb *pcb, const char *localname);
160 
161 extern const struct protent eap_protent;
162 
163 #ifdef	__cplusplus
164 }
165 #endif
166 
167 #endif /* PPP_EAP_H */
168 
169 #endif /* PPP_SUPPORT && EAP_SUPPORT */
170