1 /* 2 * EAP peer method: EAP-MD5 (RFC 3748 and RFC 1994) 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 #include "eap_common/chap.h" 20 21 22 static void * eap_md5_init(struct eap_sm *sm) 23 { 24 /* No need for private data. However, must return non-NULL to indicate 25 * success. */ 26 return (void *) 1; 27 } 28 29 30 static void eap_md5_deinit(struct eap_sm *sm, void *priv) 31 { 32 } 33 34 35 static struct wpabuf * eap_md5_process(struct eap_sm *sm, void *priv, 36 struct eap_method_ret *ret, 37 const struct wpabuf *reqData) 38 { 39 struct wpabuf *resp; 40 const u8 *pos, *challenge, *password; 41 u8 *rpos, id; 42 size_t len, challenge_len, password_len; 43 44 password = eap_get_config_password(sm, &password_len); 45 if (password == NULL) { 46 wpa_printf(MSG_INFO, "EAP-MD5: Password not configured"); 47 eap_sm_request_password(sm); 48 ret->ignore = TRUE; 49 return NULL; 50 } 51 52 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_MD5, reqData, &len); 53 if (pos == NULL || len == 0) { 54 wpa_printf(MSG_INFO, "EAP-MD5: Invalid frame (pos=%p len=%lu)", 55 pos, (unsigned long) len); 56 ret->ignore = TRUE; 57 return NULL; 58 } 59 60 /* 61 * CHAP Challenge: 62 * Value-Size (1 octet) | Value(Challenge) | Name(optional) 63 */ 64 challenge_len = *pos++; 65 if (challenge_len == 0 || challenge_len > len - 1) { 66 wpa_printf(MSG_INFO, "EAP-MD5: Invalid challenge " 67 "(challenge_len=%lu len=%lu)", 68 (unsigned long) challenge_len, (unsigned long) len); 69 ret->ignore = TRUE; 70 return NULL; 71 } 72 ret->ignore = FALSE; 73 challenge = pos; 74 wpa_hexdump(MSG_MSGDUMP, "EAP-MD5: Challenge", 75 challenge, challenge_len); 76 77 wpa_printf(MSG_DEBUG, "EAP-MD5: Generating Challenge Response"); 78 ret->methodState = METHOD_DONE; 79 ret->decision = DECISION_COND_SUCC; 80 ret->allowNotifications = TRUE; 81 82 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_MD5, 1 + CHAP_MD5_LEN, 83 EAP_CODE_RESPONSE, eap_get_id(reqData)); 84 if (resp == NULL) 85 return NULL; 86 87 /* 88 * CHAP Response: 89 * Value-Size (1 octet) | Value(Response) | Name(optional) 90 */ 91 wpabuf_put_u8(resp, CHAP_MD5_LEN); 92 93 id = eap_get_id(resp); 94 rpos = wpabuf_put(resp, CHAP_MD5_LEN); 95 chap_md5(id, password, password_len, challenge, challenge_len, rpos); 96 wpa_hexdump(MSG_MSGDUMP, "EAP-MD5: Response", rpos, CHAP_MD5_LEN); 97 98 return resp; 99 } 100 101 102 int eap_peer_md5_register(void) 103 { 104 struct eap_method *eap; 105 int ret; 106 107 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION, 108 EAP_VENDOR_IETF, EAP_TYPE_MD5, "MD5"); 109 if (eap == NULL) 110 return -1; 111 112 eap->init = eap_md5_init; 113 eap->deinit = eap_md5_deinit; 114 eap->process = eap_md5_process; 115 116 ret = eap_peer_method_register(eap); 117 if (ret) 118 eap_peer_method_free(eap); 119 return ret; 120 } 121