eap_server_gtc.c revision 8d520ff1dc2da35cdca849e982051b86468016d8 
1/*
2 * hostapd / EAP-GTC (RFC 3748)
3 * Copyright (c) 2004-2006, Jouni Malinen <j@w1.fi>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16
17#include "common.h"
18#include "eap_i.h"
19
20
21struct eap_gtc_data {
22	enum { CONTINUE, SUCCESS, FAILURE } state;
23	int prefix;
24};
25
26
27static void * eap_gtc_init(struct eap_sm *sm)
28{
29	struct eap_gtc_data *data;
30
31	data = os_zalloc(sizeof(*data));
32	if (data == NULL)
33		return NULL;
34	data->state = CONTINUE;
35
36#ifdef EAP_SERVER_FAST
37	if (sm->m && sm->m->vendor == EAP_VENDOR_IETF &&
38	    sm->m->method == EAP_TYPE_FAST) {
39		wpa_printf(MSG_DEBUG, "EAP-GTC: EAP-FAST tunnel - use prefix "
40			   "with challenge/response");
41		data->prefix = 1;
42	}
43#endif /* EAP_SERVER_FAST */
44
45	return data;
46}
47
48
49static void eap_gtc_reset(struct eap_sm *sm, void *priv)
50{
51	struct eap_gtc_data *data = priv;
52	os_free(data);
53}
54
55
56static struct wpabuf * eap_gtc_buildReq(struct eap_sm *sm, void *priv, u8 id)
57{
58	struct eap_gtc_data *data = priv;
59	struct wpabuf *req;
60	char *msg;
61	size_t msg_len;
62
63	msg = data->prefix ? "CHALLENGE=Password" : "Password";
64
65	msg_len = os_strlen(msg);
66	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GTC, msg_len,
67			    EAP_CODE_REQUEST, id);
68	if (req == NULL) {
69		wpa_printf(MSG_ERROR, "EAP-GTC: Failed to allocate memory for "
70			   "request");
71		data->state = FAILURE;
72		return NULL;
73	}
74
75	wpabuf_put_data(req, msg, msg_len);
76
77	data->state = CONTINUE;
78
79	return req;
80}
81
82
83static Boolean eap_gtc_check(struct eap_sm *sm, void *priv,
84			     struct wpabuf *respData)
85{
86	const u8 *pos;
87	size_t len;
88
89	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GTC, respData, &len);
90	if (pos == NULL || len < 1) {
91		wpa_printf(MSG_INFO, "EAP-GTC: Invalid frame");
92		return TRUE;
93	}
94
95	return FALSE;
96}
97
98
99static void eap_gtc_process(struct eap_sm *sm, void *priv,
100			    struct wpabuf *respData)
101{
102	struct eap_gtc_data *data = priv;
103	const u8 *pos;
104	size_t rlen;
105
106	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GTC, respData, &rlen);
107	if (pos == NULL || rlen < 1)
108		return; /* Should not happen - frame already validated */
109
110	wpa_hexdump_ascii_key(MSG_MSGDUMP, "EAP-GTC: Response", pos, rlen);
111
112#ifdef EAP_SERVER_FAST
113	if (data->prefix) {
114		const u8 *pos2, *end;
115		/* "RESPONSE=<user>\0<password>" */
116		if (rlen < 10) {
117			wpa_printf(MSG_DEBUG, "EAP-GTC: Too short response "
118				   "for EAP-FAST prefix");
119			data->state = FAILURE;
120			return;
121		}
122
123		end = pos + rlen;
124		pos += 9;
125		pos2 = pos;
126		while (pos2 < end && *pos2)
127			pos2++;
128		if (pos2 == end) {
129			wpa_printf(MSG_DEBUG, "EAP-GTC: No password in "
130				   "response to EAP-FAST prefix");
131			data->state = FAILURE;
132			return;
133		}
134
135		wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-GTC: Response user",
136				  pos, pos2 - pos);
137		if (sm->identity && sm->require_identity_match &&
138		    (pos2 - pos != (int) sm->identity_len ||
139		     os_memcmp(pos, sm->identity, sm->identity_len))) {
140			wpa_printf(MSG_DEBUG, "EAP-GTC: Phase 2 Identity did "
141				   "not match with required Identity");
142			wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-GTC: Expected "
143					  "identity",
144					  sm->identity, sm->identity_len);
145			data->state = FAILURE;
146			return;
147		} else {
148			os_free(sm->identity);
149			sm->identity_len = pos2 - pos;
150			sm->identity = os_malloc(sm->identity_len);
151			if (sm->identity == NULL) {
152				data->state = FAILURE;
153				return;
154			}
155			os_memcpy(sm->identity, pos, sm->identity_len);
156		}
157
158		if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
159			wpa_hexdump_ascii(MSG_DEBUG, "EAP-GTC: Phase2 "
160					  "Identity not found in the user "
161					  "database",
162					  sm->identity, sm->identity_len);
163			data->state = FAILURE;
164			return;
165		}
166
167		pos = pos2 + 1;
168		rlen = end - pos;
169		wpa_hexdump_ascii_key(MSG_MSGDUMP,
170				      "EAP-GTC: Response password",
171				      pos, rlen);
172	}
173#endif /* EAP_SERVER_FAST */
174
175	if (sm->user == NULL || sm->user->password == NULL ||
176	    sm->user->password_hash) {
177		wpa_printf(MSG_INFO, "EAP-GTC: Plaintext password not "
178			   "configured");
179		data->state = FAILURE;
180		return;
181	}
182
183	if (rlen != sm->user->password_len ||
184	    os_memcmp(pos, sm->user->password, rlen) != 0) {
185		wpa_printf(MSG_DEBUG, "EAP-GTC: Done - Failure");
186		data->state = FAILURE;
187	} else {
188		wpa_printf(MSG_DEBUG, "EAP-GTC: Done - Success");
189		data->state = SUCCESS;
190	}
191}
192
193
194static Boolean eap_gtc_isDone(struct eap_sm *sm, void *priv)
195{
196	struct eap_gtc_data *data = priv;
197	return data->state != CONTINUE;
198}
199
200
201static Boolean eap_gtc_isSuccess(struct eap_sm *sm, void *priv)
202{
203	struct eap_gtc_data *data = priv;
204	return data->state == SUCCESS;
205}
206
207
208int eap_server_gtc_register(void)
209{
210	struct eap_method *eap;
211	int ret;
212
213	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
214				      EAP_VENDOR_IETF, EAP_TYPE_GTC, "GTC");
215	if (eap == NULL)
216		return -1;
217
218	eap->init = eap_gtc_init;
219	eap->reset = eap_gtc_reset;
220	eap->buildReq = eap_gtc_buildReq;
221	eap->check = eap_gtc_check;
222	eap->process = eap_gtc_process;
223	eap->isDone = eap_gtc_isDone;
224	eap->isSuccess = eap_gtc_isSuccess;
225
226	ret = eap_server_method_register(eap);
227	if (ret)
228		eap_server_method_free(eap);
229	return ret;
230}
231