1 /*
2 * EAP peer method: EAP-MD5 (RFC 3748 and RFC 1994)
3 * Copyright (c) 2004-2012, 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 #include "eap_common/chap.h"
14
15
eap_md5_init(struct eap_sm * sm)16 static void * eap_md5_init(struct eap_sm *sm)
17 {
18 /* No need for private data. However, must return non-NULL to indicate
19 * success. */
20 return (void *) 1;
21 }
22
23
eap_md5_deinit(struct eap_sm * sm,void * priv)24 static void eap_md5_deinit(struct eap_sm *sm, void *priv)
25 {
26 }
27
28
eap_md5_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)29 static struct wpabuf * eap_md5_process(struct eap_sm *sm, void *priv,
30 struct eap_method_ret *ret,
31 const struct wpabuf *reqData)
32 {
33 struct wpabuf *resp;
34 const u8 *pos, *challenge, *password;
35 u8 *rpos, id;
36 size_t len, challenge_len, password_len;
37
38 password = eap_get_config_password(sm, &password_len);
39 if (password == NULL) {
40 wpa_printf(MSG_INFO, "EAP-MD5: Password not configured");
41 eap_sm_request_password(sm);
42 ret->ignore = TRUE;
43 return NULL;
44 }
45
46 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_MD5, reqData, &len);
47 if (pos == NULL || len == 0) {
48 wpa_printf(MSG_INFO, "EAP-MD5: Invalid frame (pos=%p len=%lu)",
49 pos, (unsigned long) len);
50 ret->ignore = TRUE;
51 return NULL;
52 }
53
54 /*
55 * CHAP Challenge:
56 * Value-Size (1 octet) | Value(Challenge) | Name(optional)
57 */
58 challenge_len = *pos++;
59 if (challenge_len == 0 || challenge_len > len - 1) {
60 wpa_printf(MSG_INFO, "EAP-MD5: Invalid challenge "
61 "(challenge_len=%lu len=%lu)",
62 (unsigned long) challenge_len, (unsigned long) len);
63 ret->ignore = TRUE;
64 return NULL;
65 }
66 ret->ignore = FALSE;
67 challenge = pos;
68 wpa_hexdump(MSG_MSGDUMP, "EAP-MD5: Challenge",
69 challenge, challenge_len);
70
71 wpa_printf(MSG_DEBUG, "EAP-MD5: Generating Challenge Response");
72 ret->methodState = METHOD_DONE;
73 ret->decision = DECISION_COND_SUCC;
74 ret->allowNotifications = TRUE;
75
76 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_MD5, 1 + CHAP_MD5_LEN,
77 EAP_CODE_RESPONSE, eap_get_id(reqData));
78 if (resp == NULL)
79 return NULL;
80
81 /*
82 * CHAP Response:
83 * Value-Size (1 octet) | Value(Response) | Name(optional)
84 */
85 wpabuf_put_u8(resp, CHAP_MD5_LEN);
86
87 id = eap_get_id(resp);
88 rpos = wpabuf_put(resp, CHAP_MD5_LEN);
89 if (chap_md5(id, password, password_len, challenge, challenge_len,
90 rpos)) {
91 wpa_printf(MSG_INFO, "EAP-MD5: CHAP MD5 operation failed");
92 ret->ignore = TRUE;
93 wpabuf_free(resp);
94 return NULL;
95 }
96 wpa_hexdump(MSG_MSGDUMP, "EAP-MD5: Response", rpos, CHAP_MD5_LEN);
97
98 return resp;
99 }
100
101
eap_peer_md5_register(void)102 int eap_peer_md5_register(void)
103 {
104 struct eap_method *eap;
105
106 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
107 EAP_VENDOR_IETF, EAP_TYPE_MD5, "MD5");
108 if (eap == NULL)
109 return -1;
110
111 eap->init = eap_md5_init;
112 eap->deinit = eap_md5_deinit;
113 eap->process = eap_md5_process;
114
115 return eap_peer_method_register(eap);
116 }
117