eap_server_gtc.c revision c28170251eb54dbf64a9074a07fee377587425b2 
1/*
2 * hostapd / EAP-GTC (RFC 3748)
3 * Copyright (c) 2004-2006, 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#include "includes.h"
10
11#include "common.h"
12#include "eap_i.h"
13
14
15struct eap_gtc_data {
16	enum { CONTINUE, SUCCESS, FAILURE } state;
17	int prefix;
18};
19
20
21static void * eap_gtc_init(struct eap_sm *sm)
22{
23	struct eap_gtc_data *data;
24
25	data = os_zalloc(sizeof(*data));
26	if (data == NULL)
27		return NULL;
28	data->state = CONTINUE;
29
30#ifdef EAP_SERVER_FAST
31	if (sm->m && sm->m->vendor == EAP_VENDOR_IETF &&
32	    sm->m->method == EAP_TYPE_FAST) {
33		wpa_printf(MSG_DEBUG, "EAP-GTC: EAP-FAST tunnel - use prefix "
34			   "with challenge/response");
35		data->prefix = 1;
36	}
37#endif /* EAP_SERVER_FAST */
38
39	return data;
40}
41
42
43static void eap_gtc_reset(struct eap_sm *sm, void *priv)
44{
45	struct eap_gtc_data *data = priv;
46	os_free(data);
47}
48
49
50static struct wpabuf * eap_gtc_buildReq(struct eap_sm *sm, void *priv, u8 id)
51{
52	struct eap_gtc_data *data = priv;
53	struct wpabuf *req;
54	char *msg;
55	size_t msg_len;
56
57	msg = data->prefix ? "CHALLENGE=Password" : "Password";
58
59	msg_len = os_strlen(msg);
60	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GTC, msg_len,
61			    EAP_CODE_REQUEST, id);
62	if (req == NULL) {
63		wpa_printf(MSG_ERROR, "EAP-GTC: Failed to allocate memory for "
64			   "request");
65		data->state = FAILURE;
66		return NULL;
67	}
68
69	wpabuf_put_data(req, msg, msg_len);
70
71	data->state = CONTINUE;
72
73	return req;
74}
75
76
77static Boolean eap_gtc_check(struct eap_sm *sm, void *priv,
78			     struct wpabuf *respData)
79{
80	const u8 *pos;
81	size_t len;
82
83	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GTC, respData, &len);
84	if (pos == NULL || len < 1) {
85		wpa_printf(MSG_INFO, "EAP-GTC: Invalid frame");
86		return TRUE;
87	}
88
89	return FALSE;
90}
91
92
93static void eap_gtc_process(struct eap_sm *sm, void *priv,
94			    struct wpabuf *respData)
95{
96	struct eap_gtc_data *data = priv;
97	const u8 *pos;
98	size_t rlen;
99
100	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GTC, respData, &rlen);
101	if (pos == NULL || rlen < 1)
102		return; /* Should not happen - frame already validated */
103
104	wpa_hexdump_ascii_key(MSG_MSGDUMP, "EAP-GTC: Response", pos, rlen);
105
106#ifdef EAP_SERVER_FAST
107	if (data->prefix) {
108		const u8 *pos2, *end;
109		/* "RESPONSE=<user>\0<password>" */
110		if (rlen < 10) {
111			wpa_printf(MSG_DEBUG, "EAP-GTC: Too short response "
112				   "for EAP-FAST prefix");
113			data->state = FAILURE;
114			return;
115		}
116
117		end = pos + rlen;
118		pos += 9;
119		pos2 = pos;
120		while (pos2 < end && *pos2)
121			pos2++;
122		if (pos2 == end) {
123			wpa_printf(MSG_DEBUG, "EAP-GTC: No password in "
124				   "response to EAP-FAST prefix");
125			data->state = FAILURE;
126			return;
127		}
128
129		wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-GTC: Response user",
130				  pos, pos2 - pos);
131		if (sm->identity && sm->require_identity_match &&
132		    (pos2 - pos != (int) sm->identity_len ||
133		     os_memcmp(pos, sm->identity, sm->identity_len))) {
134			wpa_printf(MSG_DEBUG, "EAP-GTC: Phase 2 Identity did "
135				   "not match with required Identity");
136			wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-GTC: Expected "
137					  "identity",
138					  sm->identity, sm->identity_len);
139			data->state = FAILURE;
140			return;
141		} else {
142			os_free(sm->identity);
143			sm->identity_len = pos2 - pos;
144			sm->identity = os_malloc(sm->identity_len);
145			if (sm->identity == NULL) {
146				data->state = FAILURE;
147				return;
148			}
149			os_memcpy(sm->identity, pos, sm->identity_len);
150		}
151
152		if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
153			wpa_hexdump_ascii(MSG_DEBUG, "EAP-GTC: Phase2 "
154					  "Identity not found in the user "
155					  "database",
156					  sm->identity, sm->identity_len);
157			data->state = FAILURE;
158			return;
159		}
160
161		pos = pos2 + 1;
162		rlen = end - pos;
163		wpa_hexdump_ascii_key(MSG_MSGDUMP,
164				      "EAP-GTC: Response password",
165				      pos, rlen);
166	}
167#endif /* EAP_SERVER_FAST */
168
169	if (sm->user == NULL || sm->user->password == NULL ||
170	    sm->user->password_hash) {
171		wpa_printf(MSG_INFO, "EAP-GTC: Plaintext password not "
172			   "configured");
173		data->state = FAILURE;
174		return;
175	}
176
177	if (rlen != sm->user->password_len ||
178	    os_memcmp_const(pos, sm->user->password, rlen) != 0) {
179		wpa_printf(MSG_DEBUG, "EAP-GTC: Done - Failure");
180		data->state = FAILURE;
181	} else {
182		wpa_printf(MSG_DEBUG, "EAP-GTC: Done - Success");
183		data->state = SUCCESS;
184	}
185}
186
187
188static Boolean eap_gtc_isDone(struct eap_sm *sm, void *priv)
189{
190	struct eap_gtc_data *data = priv;
191	return data->state != CONTINUE;
192}
193
194
195static Boolean eap_gtc_isSuccess(struct eap_sm *sm, void *priv)
196{
197	struct eap_gtc_data *data = priv;
198	return data->state == SUCCESS;
199}
200
201
202int eap_server_gtc_register(void)
203{
204	struct eap_method *eap;
205	int ret;
206
207	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
208				      EAP_VENDOR_IETF, EAP_TYPE_GTC, "GTC");
209	if (eap == NULL)
210		return -1;
211
212	eap->init = eap_gtc_init;
213	eap->reset = eap_gtc_reset;
214	eap->buildReq = eap_gtc_buildReq;
215	eap->check = eap_gtc_check;
216	eap->process = eap_gtc_process;
217	eap->isDone = eap_gtc_isDone;
218	eap->isSuccess = eap_gtc_isSuccess;
219
220	ret = eap_server_method_register(eap);
221	if (ret)
222		eap_server_method_free(eap);
223	return ret;
224}
225