contrib/wpa_supplicant-0.4.9/eap_md5.c

   1 /*
   2  * WPA Supplicant / EAP-MD5
   3  * Copyright (c) 2004-2005, Jouni Malinen <jkmaline@cc.hut.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 <stdlib.h>
  16 #include <stdio.h>
  17
  18 #include "common.h"
  19 #include "eap_i.h"
  20 #include "wpa_supplicant.h"
  21 #include "config_ssid.h"
  22 #include "md5.h"
  23 #include "crypto.h"
  24
  25
  26 static void * eap_md5_init(struct eap_sm *sm)
  27 {
  28         return (void *) 1;
  29 }
  30
  31
  32 static void eap_md5_deinit(struct eap_sm *sm, void *priv)
  33 {
  34 }
  35
  36
  37 static u8 * eap_md5_process(struct eap_sm *sm, void *priv,
  38                             struct eap_method_ret *ret,
  39                             const u8 *reqData, size_t reqDataLen,
  40                             size_t *respDataLen)
  41 {
  42         struct wpa_ssid *config = eap_get_config(sm);
  43         const struct eap_hdr *req;
  44         struct eap_hdr *resp;
  45         const u8 *pos, *challenge;
  46         u8 *rpos;
  47         int challenge_len;
  48         size_t len;
  49         const u8 *addr[3];
  50         size_t elen[3];
  51
  52         if (config == NULL || config->password == NULL) {
  53                 wpa_printf(MSG_INFO, "EAP-MD5: Password not configured");
  54                 eap_sm_request_password(sm, config);
  55                 ret->ignore = TRUE;
  56                 return NULL;
  57         }
  58
  59         pos = eap_hdr_validate(EAP_TYPE_MD5, reqData, reqDataLen, &len);
  60         if (pos == NULL || len == 0) {
  61                 wpa_printf(MSG_INFO, "EAP-MD5: Invalid frame (pos=%p len=%lu)",
  62                            pos, (unsigned long) len);
  63                 ret->ignore = TRUE;
  64                 return NULL;
  65         }
  66         req = (const struct eap_hdr *) reqData;
  67         challenge_len = *pos++;
  68         if (challenge_len == 0 ||
  69             challenge_len > len - 1) {
  70                 wpa_printf(MSG_INFO, "EAP-MD5: Invalid challenge "
  71                            "(challenge_len=%d len=%lu)",
  72                            challenge_len, (unsigned long) len);
  73                 ret->ignore = TRUE;
  74                 return NULL;
  75         }
  76         ret->ignore = FALSE;
  77         challenge = pos;
  78         wpa_hexdump(MSG_MSGDUMP, "EAP-MD5: Challenge",
  79                     challenge, challenge_len);
  80
  81         wpa_printf(MSG_DEBUG, "EAP-MD5: generating Challenge Response");
  82         ret->methodState = METHOD_DONE;
  83         ret->decision = DECISION_UNCOND_SUCC;
  84         ret->allowNotifications = TRUE;
  85
  86         *respDataLen = sizeof(struct eap_hdr) + 1 + 1 + MD5_MAC_LEN;
  87         resp = malloc(*respDataLen);
  88         if (resp == NULL)
  89                 return NULL;
  90         resp->code = EAP_CODE_RESPONSE;
  91         resp->identifier = req->identifier;
  92         resp->length = host_to_be16(*respDataLen);
  93         rpos = (u8 *) (resp + 1);
  94         *rpos++ = EAP_TYPE_MD5;
  95         *rpos++ = MD5_MAC_LEN; /* Value-Size */
  96
  97         addr[0] = &resp->identifier;
  98         elen[0] = 1;
  99         addr[1] = config->password;
 100         elen[1] = config->password_len;
 101         addr[2] = challenge;
 102         elen[2] = challenge_len;
 103         md5_vector(3, addr, elen, rpos);
 104         wpa_hexdump(MSG_MSGDUMP, "EAP-MD5: Response", rpos, MD5_MAC_LEN);
 105
 106         return (u8 *) resp;
 107 }
 108
 109
 110 const struct eap_method eap_method_md5 =
 111 {
 112         .method = EAP_TYPE_MD5,
 113         .name = "MD5",
 114         .init = eap_md5_init,
 115         .deinit = eap_md5_deinit,
 116         .process = eap_md5_process,
 117 };