contrib/wpa_supplicant-0.5.8/eap_gtc.c

   1 /*
   2  * EAP peer method: 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
  21 struct eap_gtc_data {
  22         int prefix;
  23 };
  24
  25
  26 static void * eap_gtc_init(struct eap_sm *sm)
  27 {
  28         struct eap_gtc_data *data;
  29         data = os_zalloc(sizeof(*data));
  30         if (data == NULL)
  31                 return NULL;
  32
  33         if (sm->m && sm->m->method == EAP_TYPE_FAST) {
  34                 wpa_printf(MSG_DEBUG, "EAP-GTC: EAP-FAST tunnel - use prefix "
  35                            "with challenge/response");
  36                 data->prefix = 1;
  37         }
  38         return data;
  39 }
  40
  41
  42 static void eap_gtc_deinit(struct eap_sm *sm, void *priv)
  43 {
  44         struct eap_gtc_data *data = priv;
  45         os_free(data);
  46 }
  47
  48
  49 static u8 * eap_gtc_process(struct eap_sm *sm, void *priv,
  50                             struct eap_method_ret *ret,
  51                             const u8 *reqData, size_t reqDataLen,
  52                             size_t *respDataLen)
  53 {
  54         struct eap_gtc_data *data = priv;
  55         const struct eap_hdr *req;
  56         struct eap_hdr *resp;
  57         const u8 *pos, *password, *identity;
  58         u8 *rpos;
  59         size_t password_len, identity_len, len, plen;
  60         int otp;
  61
  62         pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_GTC,
  63                                reqData, reqDataLen, &len);
  64         if (pos == NULL) {
  65                 ret->ignore = TRUE;
  66                 return NULL;
  67         }
  68         req = (const struct eap_hdr *) reqData;
  69
  70         wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-GTC: Request message", pos, len);
  71         if (data->prefix &&
  72             (len < 10 || os_memcmp(pos, "CHALLENGE=", 10) != 0)) {
  73                 wpa_printf(MSG_DEBUG, "EAP-GTC: Challenge did not start with "
  74                            "expected prefix");
  75
  76                 /* Send an empty response in order to allow tunneled
  77                  * acknowledgement of the failure. This will also cover the
  78                  * error case which seems to use EAP-MSCHAPv2 like error
  79                  * reporting with EAP-GTC inside EAP-FAST tunnel. */
  80                 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GTC,
  81                                      respDataLen, 0, EAP_CODE_RESPONSE,
  82                                      req->identifier, NULL);
  83                 return (u8 *) resp;
  84         }
  85
  86         password = eap_get_config_otp(sm, &password_len);
  87         if (password)
  88                 otp = 1;
  89         else {
  90                 password = eap_get_config_password(sm, &password_len);
  91                 otp = 0;
  92         }
  93
  94         if (password == NULL) {
  95                 wpa_printf(MSG_INFO, "EAP-GTC: Password not configured");
  96                 eap_sm_request_otp(sm, (const char *) pos, len);
  97                 ret->ignore = TRUE;
  98                 return NULL;
  99         }
 100
 101         ret->ignore = FALSE;
 102
 103         ret->methodState = data->prefix ? METHOD_MAY_CONT : METHOD_DONE;
 104         ret->decision = DECISION_COND_SUCC;
 105         ret->allowNotifications = FALSE;
 106
 107         plen = password_len;
 108         identity = eap_get_config_identity(sm, &identity_len);
 109         if (identity == NULL)
 110                 return NULL;
 111         if (data->prefix)
 112                 plen += 9 + identity_len + 1;
 113         resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_GTC, respDataLen,
 114                              plen, EAP_CODE_RESPONSE, req->identifier, &rpos);
 115         if (resp == NULL)
 116                 return NULL;
 117         if (data->prefix) {
 118                 os_memcpy(rpos, "RESPONSE=", 9);
 119                 rpos += 9;
 120                 os_memcpy(rpos, identity, identity_len);
 121                 rpos += identity_len;
 122                 *rpos++ = '\0';
 123         }
 124         os_memcpy(rpos, password, password_len);
 125         wpa_hexdump_ascii_key(MSG_MSGDUMP, "EAP-GTC: Response",
 126                               (u8 *) (resp + 1) + 1, plen);
 127
 128         if (otp) {
 129                 wpa_printf(MSG_DEBUG, "EAP-GTC: Forgetting used password");
 130                 eap_clear_config_otp(sm);
 131         }
 132
 133         return (u8 *) resp;
 134 }
 135
 136
 137 int eap_peer_gtc_register(void)
 138 {
 139         struct eap_method *eap;
 140         int ret;
 141
 142         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 143                                     EAP_VENDOR_IETF, EAP_TYPE_GTC, "GTC");
 144         if (eap == NULL)
 145                 return -1;
 146
 147         eap->init = eap_gtc_init;
 148         eap->deinit = eap_gtc_deinit;
 149         eap->process = eap_gtc_process;
 150
 151         ret = eap_peer_method_register(eap);
 152         if (ret)
 153                 eap_peer_method_free(eap);
 154         return ret;
 155 }