1 /* 2 * EAP peer method: LEAP 3 * Copyright (c) 2004-2006, Jouni Malinen <j (at) 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 "ms_funcs.h" 20 #include "crypto.h" 21 22 #define LEAP_VERSION 1 23 #define LEAP_CHALLENGE_LEN 8 24 #define LEAP_RESPONSE_LEN 24 25 #define LEAP_KEY_LEN 16 26 27 28 struct eap_leap_data { 29 enum { 30 LEAP_WAIT_CHALLENGE, 31 LEAP_WAIT_SUCCESS, 32 LEAP_WAIT_RESPONSE, 33 LEAP_DONE 34 } state; 35 36 u8 peer_challenge[LEAP_CHALLENGE_LEN]; 37 u8 peer_response[LEAP_RESPONSE_LEN]; 38 39 u8 ap_challenge[LEAP_CHALLENGE_LEN]; 40 u8 ap_response[LEAP_RESPONSE_LEN]; 41 }; 42 43 44 static void * eap_leap_init(struct eap_sm *sm) 45 { 46 struct eap_leap_data *data; 47 48 data = os_zalloc(sizeof(*data)); 49 if (data == NULL) 50 return NULL; 51 data->state = LEAP_WAIT_CHALLENGE; 52 53 sm->leap_done = FALSE; 54 return data; 55 } 56 57 58 static void eap_leap_deinit(struct eap_sm *sm, void *priv) 59 { 60 os_free(priv); 61 } 62 63 64 static u8 * eap_leap_process_request(struct eap_sm *sm, void *priv, 65 struct eap_method_ret *ret, 66 const u8 *reqData, size_t reqDataLen, 67 size_t *respDataLen) 68 { 69 struct eap_leap_data *data = priv; 70 const struct eap_hdr *req; 71 struct eap_hdr *resp; 72 const u8 *pos, *challenge, *identity, *password; 73 u8 challenge_len, *rpos; 74 size_t identity_len, password_len; 75 76 wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Request"); 77 78 identity = eap_get_config_identity(sm, &identity_len); 79 password = eap_get_config_password(sm, &password_len); 80 if (identity == NULL || password == NULL) 81 return NULL; 82 83 req = (const struct eap_hdr *) reqData; 84 pos = (const u8 *) (req + 1); 85 if (reqDataLen < sizeof(*req) + 4 || *pos != EAP_TYPE_LEAP) { 86 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid EAP-Request frame"); 87 ret->ignore = TRUE; 88 return NULL; 89 } 90 pos++; 91 92 if (*pos != LEAP_VERSION) { 93 wpa_printf(MSG_WARNING, "EAP-LEAP: Unsupported LEAP version " 94 "%d", *pos); 95 ret->ignore = TRUE; 96 return NULL; 97 } 98 pos++; 99 100 pos++; /* skip unused byte */ 101 102 challenge_len = *pos++; 103 if (challenge_len != LEAP_CHALLENGE_LEN || 104 challenge_len > reqDataLen - sizeof(*req) - 4) { 105 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid challenge " 106 "(challenge_len=%d reqDataLen=%lu)", 107 challenge_len, (unsigned long) reqDataLen); 108 ret->ignore = TRUE; 109 return NULL; 110 } 111 challenge = pos; 112 os_memcpy(data->peer_challenge, challenge, LEAP_CHALLENGE_LEN); 113 wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Challenge from AP", 114 challenge, LEAP_CHALLENGE_LEN); 115 116 wpa_printf(MSG_DEBUG, "EAP-LEAP: Generating Challenge Response"); 117 118 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_LEAP, respDataLen, 119 3 + LEAP_RESPONSE_LEN + identity_len, 120 EAP_CODE_RESPONSE, req->identifier, &rpos); 121 if (resp == NULL) 122 return NULL; 123 *rpos++ = LEAP_VERSION; 124 *rpos++ = 0; /* unused */ 125 *rpos++ = LEAP_RESPONSE_LEN; 126 nt_challenge_response(challenge, password, password_len, rpos); 127 os_memcpy(data->peer_response, rpos, LEAP_RESPONSE_LEN); 128 wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Response", 129 rpos, LEAP_RESPONSE_LEN); 130 rpos += LEAP_RESPONSE_LEN; 131 os_memcpy(rpos, identity, identity_len); 132 133 data->state = LEAP_WAIT_SUCCESS; 134 135 return (u8 *) resp; 136 } 137 138 139 static u8 * eap_leap_process_success(struct eap_sm *sm, void *priv, 140 struct eap_method_ret *ret, 141 const u8 *reqData, size_t *respDataLen) 142 { 143 struct eap_leap_data *data = priv; 144 const struct eap_hdr *req; 145 struct eap_hdr *resp; 146 u8 *pos; 147 const u8 *identity; 148 size_t identity_len; 149 150 wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Success"); 151 152 identity = eap_get_config_identity(sm, &identity_len); 153 if (identity == NULL) 154 return NULL; 155 156 if (data->state != LEAP_WAIT_SUCCESS) { 157 wpa_printf(MSG_INFO, "EAP-LEAP: EAP-Success received in " 158 "unexpected state (%d) - ignored", data->state); 159 ret->ignore = TRUE; 160 return NULL; 161 } 162 163 req = (const struct eap_hdr *) reqData; 164 165 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_LEAP, respDataLen, 166 3 + LEAP_CHALLENGE_LEN + identity_len, 167 EAP_CODE_REQUEST, req->identifier, &pos); 168 if (resp == NULL) 169 return NULL; 170 *pos++ = LEAP_VERSION; 171 *pos++ = 0; /* unused */ 172 *pos++ = LEAP_CHALLENGE_LEN; 173 if (hostapd_get_rand(pos, LEAP_CHALLENGE_LEN)) { 174 wpa_printf(MSG_WARNING, "EAP-LEAP: Failed to read random data " 175 "for challenge"); 176 os_free(resp); 177 ret->ignore = TRUE; 178 return NULL; 179 } 180 os_memcpy(data->ap_challenge, pos, LEAP_CHALLENGE_LEN); 181 wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Challenge to AP/AS", pos, 182 LEAP_CHALLENGE_LEN); 183 pos += LEAP_CHALLENGE_LEN; 184 os_memcpy(pos, identity, identity_len); 185 186 data->state = LEAP_WAIT_RESPONSE; 187 188 return (u8 *) resp; 189 } 190 191 192 static u8 * eap_leap_process_response(struct eap_sm *sm, void *priv, 193 struct eap_method_ret *ret, 194 const u8 *reqData, size_t reqDataLen) 195 { 196 struct eap_leap_data *data = priv; 197 const struct eap_hdr *resp; 198 const u8 *pos, *password; 199 u8 response_len, pw_hash[16], pw_hash_hash[16], 200 expected[LEAP_RESPONSE_LEN]; 201 size_t password_len; 202 203 wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Response"); 204 205 password = eap_get_config_password(sm, &password_len); 206 if (password == NULL) 207 return NULL; 208 209 resp = (const struct eap_hdr *) reqData; 210 pos = (const u8 *) (resp + 1); 211 if (reqDataLen < sizeof(*resp) + 4 || *pos != EAP_TYPE_LEAP) { 212 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid EAP-Response frame"); 213 ret->ignore = TRUE; 214 return NULL; 215 } 216 pos++; 217 218 if (*pos != LEAP_VERSION) { 219 wpa_printf(MSG_WARNING, "EAP-LEAP: Unsupported LEAP version " 220 "%d", *pos); 221 ret->ignore = TRUE; 222 return NULL; 223 } 224 pos++; 225 226 pos++; /* skip unused byte */ 227 228 response_len = *pos++; 229 if (response_len != LEAP_RESPONSE_LEN || 230 response_len > reqDataLen - sizeof(*resp) - 4) { 231 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid response " 232 "(response_len=%d reqDataLen=%lu)", 233 response_len, (unsigned long) reqDataLen); 234 ret->ignore = TRUE; 235 return NULL; 236 } 237 238 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: Response from AP", 239 pos, LEAP_RESPONSE_LEN); 240 os_memcpy(data->ap_response, pos, LEAP_RESPONSE_LEN); 241 242 nt_password_hash(password, password_len, pw_hash); 243 hash_nt_password_hash(pw_hash, pw_hash_hash); 244 challenge_response(data->ap_challenge, pw_hash_hash, expected); 245 246 ret->methodState = METHOD_DONE; 247 ret->allowNotifications = FALSE; 248 249 if (os_memcmp(pos, expected, LEAP_RESPONSE_LEN) != 0) { 250 wpa_printf(MSG_WARNING, "EAP-LEAP: AP sent an invalid " 251 "response - authentication failed"); 252 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: Expected response from AP", 253 expected, LEAP_RESPONSE_LEN); 254 ret->decision = DECISION_FAIL; 255 return NULL; 256 } 257 258 ret->decision = DECISION_UNCOND_SUCC; 259 260 /* LEAP is somewhat odd method since it sends EAP-Success in the middle 261 * of the authentication. Use special variable to transit EAP state 262 * machine to SUCCESS state. */ 263 sm->leap_done = TRUE; 264 data->state = LEAP_DONE; 265 266 /* No more authentication messages expected; AP will send EAPOL-Key 267 * frames if encryption is enabled. */ 268 return NULL; 269 } 270 271 272 static u8 * eap_leap_process(struct eap_sm *sm, void *priv, 273 struct eap_method_ret *ret, 274 const u8 *reqData, size_t reqDataLen, 275 size_t *respDataLen) 276 { 277 const struct eap_hdr *eap; 278 size_t len, password_len; 279 const u8 *password; 280 281 password = eap_get_config_password(sm, &password_len); 282 if (password == NULL) { 283 wpa_printf(MSG_INFO, "EAP-LEAP: Password not configured"); 284 eap_sm_request_password(sm); 285 ret->ignore = TRUE; 286 return NULL; 287 } 288 289 eap = (const struct eap_hdr *) reqData; 290 291 if (reqDataLen < sizeof(*eap) || 292 (len = be_to_host16(eap->length)) > reqDataLen) { 293 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid frame"); 294 ret->ignore = TRUE; 295 return NULL; 296 } 297 298 ret->ignore = FALSE; 299 ret->allowNotifications = TRUE; 300 ret->methodState = METHOD_MAY_CONT; 301 ret->decision = DECISION_FAIL; 302 303 sm->leap_done = FALSE; 304 305 switch (eap->code) { 306 case EAP_CODE_REQUEST: 307 return eap_leap_process_request(sm, priv, ret, reqData, len, 308 respDataLen); 309 case EAP_CODE_SUCCESS: 310 return eap_leap_process_success(sm, priv, ret, reqData, 311 respDataLen); 312 case EAP_CODE_RESPONSE: 313 return eap_leap_process_response(sm, priv, ret, reqData, len); 314 default: 315 wpa_printf(MSG_INFO, "EAP-LEAP: Unexpected EAP code (%d) - " 316 "ignored", eap->code); 317 ret->ignore = TRUE; 318 return NULL; 319 } 320 } 321 322 323 static Boolean eap_leap_isKeyAvailable(struct eap_sm *sm, void *priv) 324 { 325 struct eap_leap_data *data = priv; 326 return data->state == LEAP_DONE; 327 } 328 329 330 static u8 * eap_leap_getKey(struct eap_sm *sm, void *priv, size_t *len) 331 { 332 struct eap_leap_data *data = priv; 333 u8 *key, pw_hash_hash[16], pw_hash[16]; 334 const u8 *addr[5], *password; 335 size_t elen[5], password_len; 336 337 if (data->state != LEAP_DONE) 338 return NULL; 339 340 password = eap_get_config_password(sm, &password_len); 341 if (password == NULL) 342 return NULL; 343 344 key = os_malloc(LEAP_KEY_LEN); 345 if (key == NULL) 346 return NULL; 347 348 nt_password_hash(password, password_len, pw_hash); 349 hash_nt_password_hash(pw_hash, pw_hash_hash); 350 wpa_hexdump_key(MSG_DEBUG, "EAP-LEAP: pw_hash_hash", 351 pw_hash_hash, 16); 352 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: peer_challenge", 353 data->peer_challenge, LEAP_CHALLENGE_LEN); 354 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: peer_response", 355 data->peer_response, LEAP_RESPONSE_LEN); 356 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: ap_challenge", 357 data->ap_challenge, LEAP_CHALLENGE_LEN); 358 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: ap_response", 359 data->ap_response, LEAP_RESPONSE_LEN); 360 361 addr[0] = pw_hash_hash; 362 elen[0] = 16; 363 addr[1] = data->ap_challenge; 364 elen[1] = LEAP_CHALLENGE_LEN; 365 addr[2] = data->ap_response; 366 elen[2] = LEAP_RESPONSE_LEN; 367 addr[3] = data->peer_challenge; 368 elen[3] = LEAP_CHALLENGE_LEN; 369 addr[4] = data->peer_response; 370 elen[4] = LEAP_RESPONSE_LEN; 371 md5_vector(5, addr, elen, key); 372 wpa_hexdump_key(MSG_DEBUG, "EAP-LEAP: master key", key, LEAP_KEY_LEN); 373 *len = LEAP_KEY_LEN; 374 375 return key; 376 } 377 378 379 int eap_peer_leap_register(void) 380 { 381 struct eap_method *eap; 382 int ret; 383 384 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION, 385 EAP_VENDOR_IETF, EAP_TYPE_LEAP, "LEAP"); 386 if (eap == NULL) 387 return -1; 388 389 eap->init = eap_leap_init; 390 eap->deinit = eap_leap_deinit; 391 eap->process = eap_leap_process; 392 eap->isKeyAvailable = eap_leap_isKeyAvailable; 393 eap->getKey = eap_leap_getKey; 394 395 ret = eap_peer_method_register(eap); 396 if (ret) 397 eap_peer_method_free(eap); 398 return ret; 399 } 400