/* * hostapd / EAP Full Authenticator state machine (RFC 4137) * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi> * * This software may be distributed under the terms of the BSD license. * See README for more details. * * This state machine is based on the full authenticator state machine defined * in RFC 4137. However, to support backend authentication in RADIUS * authentication server functionality, parts of backend authenticator (also * from RFC 4137) are mixed in. This functionality is enabled by setting * backend_auth configuration variable to TRUE. */ #include "includes.h" #include "common.h" #include "eap_i.h" #include "state_machine.h" #include "common/wpa_ctrl.h" #define STATE_MACHINE_DATA struct eap_sm #define STATE_MACHINE_DEBUG_PREFIX "EAP" #define EAP_MAX_AUTH_ROUNDS 50 static void eap_user_free(struct eap_user *user); /* EAP state machines are described in RFC 4137 */ static int eap_sm_calculateTimeout(struct eap_sm *sm, int retransCount, int eapSRTT, int eapRTTVAR, int methodTimeout); static void eap_sm_parseEapResp(struct eap_sm *sm, const struct wpabuf *resp); static int eap_sm_getId(const struct wpabuf *data); static struct wpabuf * eap_sm_buildSuccess(struct eap_sm *sm, u8 id); static struct wpabuf * eap_sm_buildFailure(struct eap_sm *sm, u8 id); static int eap_sm_nextId(struct eap_sm *sm, int id); static void eap_sm_Policy_update(struct eap_sm *sm, const u8 *nak_list, size_t len); static EapType eap_sm_Policy_getNextMethod(struct eap_sm *sm, int *vendor); static int eap_sm_Policy_getDecision(struct eap_sm *sm); static Boolean eap_sm_Policy_doPickUp(struct eap_sm *sm, EapType method); static int eap_copy_buf(struct wpabuf **dst, const struct wpabuf *src) { if (src == NULL) return -1; wpabuf_free(*dst); *dst = wpabuf_dup(src); return *dst ? 0 : -1; } static int eap_copy_data(u8 **dst, size_t *dst_len, const u8 *src, size_t src_len) { if (src == NULL) return -1; os_free(*dst); *dst = os_malloc(src_len); if (*dst) { os_memcpy(*dst, src, src_len); *dst_len = src_len; return 0; } else { *dst_len = 0; return -1; } } #define EAP_COPY(dst, src) \ eap_copy_data((dst), (dst ## Len), (src), (src ## Len)) /** * eap_user_get - Fetch user information from the database * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * @identity: Identity (User-Name) of the user * @identity_len: Length of identity in bytes * @phase2: 0 = EAP phase1 user, 1 = EAP phase2 (tunneled) user * Returns: 0 on success, or -1 on failure * * This function is used to fetch user information for EAP. The user will be * selected based on the specified identity. sm->user and * sm->user_eap_method_index are updated for the new user when a matching user * is found. sm->user can be used to get user information (e.g., password). */ int eap_user_get(struct eap_sm *sm, const u8 *identity, size_t identity_len, int phase2) { struct eap_user *user; if (sm == NULL || sm->eapol_cb == NULL || sm->eapol_cb->get_eap_user == NULL) return -1; eap_user_free(sm->user); sm->user = NULL; user = os_zalloc(sizeof(*user)); if (user == NULL) return -1; if (sm->eapol_cb->get_eap_user(sm->eapol_ctx, identity, identity_len, phase2, user) != 0) { eap_user_free(user); return -1; } sm->user = user; sm->user_eap_method_index = 0; return 0; } void eap_log_msg(struct eap_sm *sm, const char *fmt, ...) { va_list ap; char *buf; int buflen; if (sm == NULL || sm->eapol_cb == NULL || sm->eapol_cb->log_msg == NULL) return; va_start(ap, fmt); buflen = vsnprintf(NULL, 0, fmt, ap) + 1; va_end(ap); buf = os_malloc(buflen); if (buf == NULL) return; va_start(ap, fmt); vsnprintf(buf, buflen, fmt, ap); va_end(ap); sm->eapol_cb->log_msg(sm->eapol_ctx, buf); os_free(buf); } SM_STATE(EAP, DISABLED) { SM_ENTRY(EAP, DISABLED); sm->num_rounds = 0; } SM_STATE(EAP, INITIALIZE) { SM_ENTRY(EAP, INITIALIZE); if (sm->eap_if.eapRestart && !sm->eap_server && sm->identity) { /* * Need to allow internal Identity method to be used instead * of passthrough at the beginning of reauthentication. */ eap_server_clear_identity(sm); } sm->currentId = -1; sm->eap_if.eapSuccess = FALSE; sm->eap_if.eapFail = FALSE; sm->eap_if.eapTimeout = FALSE; bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen); sm->eap_if.eapKeyData = NULL; sm->eap_if.eapKeyDataLen = 0; sm->eap_if.eapKeyAvailable = FALSE; sm->eap_if.eapRestart = FALSE; /* * This is not defined in RFC 4137, but method state needs to be * reseted here so that it does not remain in success state when * re-authentication starts. */ if (sm->m && sm->eap_method_priv) { sm->m->reset(sm, sm->eap_method_priv); sm->eap_method_priv = NULL; } sm->m = NULL; sm->user_eap_method_index = 0; if (sm->backend_auth) { sm->currentMethod = EAP_TYPE_NONE; /* parse rxResp, respId, respMethod */ eap_sm_parseEapResp(sm, sm->eap_if.eapRespData); if (sm->rxResp) { sm->currentId = sm->respId; } } sm->num_rounds = 0; sm->method_pending = METHOD_PENDING_NONE; wpa_msg(sm->msg_ctx, MSG_INFO, WPA_EVENT_EAP_STARTED MACSTR, MAC2STR(sm->peer_addr)); } SM_STATE(EAP, PICK_UP_METHOD) { SM_ENTRY(EAP, PICK_UP_METHOD); if (eap_sm_Policy_doPickUp(sm, sm->respMethod)) { sm->currentMethod = sm->respMethod; if (sm->m && sm->eap_method_priv) { sm->m->reset(sm, sm->eap_method_priv); sm->eap_method_priv = NULL; } sm->m = eap_server_get_eap_method(EAP_VENDOR_IETF, sm->currentMethod); if (sm->m && sm->m->initPickUp) { sm->eap_method_priv = sm->m->initPickUp(sm); if (sm->eap_method_priv == NULL) { wpa_printf(MSG_DEBUG, "EAP: Failed to " "initialize EAP method %d", sm->currentMethod); sm->m = NULL; sm->currentMethod = EAP_TYPE_NONE; } } else { sm->m = NULL; sm->currentMethod = EAP_TYPE_NONE; } } wpa_msg(sm->msg_ctx, MSG_INFO, WPA_EVENT_EAP_PROPOSED_METHOD "method=%u", sm->currentMethod); } SM_STATE(EAP, IDLE) { SM_ENTRY(EAP, IDLE); sm->eap_if.retransWhile = eap_sm_calculateTimeout( sm, sm->retransCount, sm->eap_if.eapSRTT, sm->eap_if.eapRTTVAR, sm->methodTimeout); } SM_STATE(EAP, RETRANSMIT) { SM_ENTRY(EAP, RETRANSMIT); sm->retransCount++; if (sm->retransCount <= sm->MaxRetrans && sm->lastReqData) { if (eap_copy_buf(&sm->eap_if.eapReqData, sm->lastReqData) == 0) sm->eap_if.eapReq = TRUE; } } SM_STATE(EAP, RECEIVED) { SM_ENTRY(EAP, RECEIVED); /* parse rxResp, respId, respMethod */ eap_sm_parseEapResp(sm, sm->eap_if.eapRespData); sm->num_rounds++; } SM_STATE(EAP, DISCARD) { SM_ENTRY(EAP, DISCARD); sm->eap_if.eapResp = FALSE; sm->eap_if.eapNoReq = TRUE; } SM_STATE(EAP, SEND_REQUEST) { SM_ENTRY(EAP, SEND_REQUEST); sm->retransCount = 0; if (sm->eap_if.eapReqData) { if (eap_copy_buf(&sm->lastReqData, sm->eap_if.eapReqData) == 0) { sm->eap_if.eapResp = FALSE; sm->eap_if.eapReq = TRUE; } else { sm->eap_if.eapResp = FALSE; sm->eap_if.eapReq = FALSE; } } else { wpa_printf(MSG_INFO, "EAP: SEND_REQUEST - no eapReqData"); sm->eap_if.eapResp = FALSE; sm->eap_if.eapReq = FALSE; sm->eap_if.eapNoReq = TRUE; } } SM_STATE(EAP, INTEGRITY_CHECK) { SM_ENTRY(EAP, INTEGRITY_CHECK); if (!eap_hdr_len_valid(sm->eap_if.eapRespData, 1)) { sm->ignore = TRUE; return; } if (sm->m->check) { sm->ignore = sm->m->check(sm, sm->eap_method_priv, sm->eap_if.eapRespData); } } SM_STATE(EAP, METHOD_REQUEST) { SM_ENTRY(EAP, METHOD_REQUEST); if (sm->m == NULL) { wpa_printf(MSG_DEBUG, "EAP: method not initialized"); return; } sm->currentId = eap_sm_nextId(sm, sm->currentId); wpa_printf(MSG_DEBUG, "EAP: building EAP-Request: Identifier %d", sm->currentId); sm->lastId = sm->currentId; wpabuf_free(sm->eap_if.eapReqData); sm->eap_if.eapReqData = sm->m->buildReq(sm, sm->eap_method_priv, sm->currentId); if (sm->m->getTimeout) sm->methodTimeout = sm->m->getTimeout(sm, sm->eap_method_priv); else sm->methodTimeout = 0; } SM_STATE(EAP, METHOD_RESPONSE) { SM_ENTRY(EAP, METHOD_RESPONSE); if (!eap_hdr_len_valid(sm->eap_if.eapRespData, 1)) return; sm->m->process(sm, sm->eap_method_priv, sm->eap_if.eapRespData); if (sm->m->isDone(sm, sm->eap_method_priv)) { eap_sm_Policy_update(sm, NULL, 0); bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen); if (sm->m->getKey) { sm->eap_if.eapKeyData = sm->m->getKey( sm, sm->eap_method_priv, &sm->eap_if.eapKeyDataLen); } else { sm->eap_if.eapKeyData = NULL; sm->eap_if.eapKeyDataLen = 0; } sm->methodState = METHOD_END; } else { sm->methodState = METHOD_CONTINUE; } } SM_STATE(EAP, PROPOSE_METHOD) { int vendor; EapType type; SM_ENTRY(EAP, PROPOSE_METHOD); try_another_method: type = eap_sm_Policy_getNextMethod(sm, &vendor); if (vendor == EAP_VENDOR_IETF) sm->currentMethod = type; else sm->currentMethod = EAP_TYPE_EXPANDED; if (sm->m && sm->eap_method_priv) { sm->m->reset(sm, sm->eap_method_priv); sm->eap_method_priv = NULL; } sm->m = eap_server_get_eap_method(vendor, type); if (sm->m) { sm->eap_method_priv = sm->m->init(sm); if (sm->eap_method_priv == NULL) { wpa_printf(MSG_DEBUG, "EAP: Failed to initialize EAP " "method %d", sm->currentMethod); sm->m = NULL; sm->currentMethod = EAP_TYPE_NONE; goto try_another_method; } } if (sm->m == NULL) { wpa_printf(MSG_DEBUG, "EAP: Could not find suitable EAP method"); eap_log_msg(sm, "Could not find suitable EAP method"); sm->decision = DECISION_FAILURE; return; } if (sm->currentMethod == EAP_TYPE_IDENTITY || sm->currentMethod == EAP_TYPE_NOTIFICATION) sm->methodState = METHOD_CONTINUE; else sm->methodState = METHOD_PROPOSED; wpa_msg(sm->msg_ctx, MSG_INFO, WPA_EVENT_EAP_PROPOSED_METHOD "vendor=%u method=%u", vendor, sm->currentMethod); eap_log_msg(sm, "Propose EAP method vendor=%u method=%u", vendor, sm->currentMethod); } SM_STATE(EAP, NAK) { const struct eap_hdr *nak; size_t len = 0; const u8 *pos; const u8 *nak_list = NULL; SM_ENTRY(EAP, NAK); if (sm->eap_method_priv) { sm->m->reset(sm, sm->eap_method_priv); sm->eap_method_priv = NULL; } sm->m = NULL; if (!eap_hdr_len_valid(sm->eap_if.eapRespData, 1)) return; nak = wpabuf_head(sm->eap_if.eapRespData); if (nak && wpabuf_len(sm->eap_if.eapRespData) > sizeof(*nak)) { len = be_to_host16(nak->length); if (len > wpabuf_len(sm->eap_if.eapRespData)) len = wpabuf_len(sm->eap_if.eapRespData); pos = (const u8 *) (nak + 1); len -= sizeof(*nak); if (*pos == EAP_TYPE_NAK) { pos++; len--; nak_list = pos; } } eap_sm_Policy_update(sm, nak_list, len); } SM_STATE(EAP, SELECT_ACTION) { SM_ENTRY(EAP, SELECT_ACTION); sm->decision = eap_sm_Policy_getDecision(sm); } SM_STATE(EAP, TIMEOUT_FAILURE) { SM_ENTRY(EAP, TIMEOUT_FAILURE); sm->eap_if.eapTimeout = TRUE; } SM_STATE(EAP, FAILURE) { SM_ENTRY(EAP, FAILURE); wpabuf_free(sm->eap_if.eapReqData); sm->eap_if.eapReqData = eap_sm_buildFailure(sm, sm->currentId); wpabuf_free(sm->lastReqData); sm->lastReqData = NULL; sm->eap_if.eapFail = TRUE; wpa_msg(sm->msg_ctx, MSG_INFO, WPA_EVENT_EAP_FAILURE MACSTR, MAC2STR(sm->peer_addr)); } SM_STATE(EAP, SUCCESS) { SM_ENTRY(EAP, SUCCESS); wpabuf_free(sm->eap_if.eapReqData); sm->eap_if.eapReqData = eap_sm_buildSuccess(sm, sm->currentId); wpabuf_free(sm->lastReqData); sm->lastReqData = NULL; if (sm->eap_if.eapKeyData) sm->eap_if.eapKeyAvailable = TRUE; sm->eap_if.eapSuccess = TRUE; wpa_msg(sm->msg_ctx, MSG_INFO, WPA_EVENT_EAP_SUCCESS MACSTR, MAC2STR(sm->peer_addr)); } SM_STATE(EAP, INITIALIZE_PASSTHROUGH) { SM_ENTRY(EAP, INITIALIZE_PASSTHROUGH); wpabuf_free(sm->eap_if.aaaEapRespData); sm->eap_if.aaaEapRespData = NULL; } SM_STATE(EAP, IDLE2) { SM_ENTRY(EAP, IDLE2); sm->eap_if.retransWhile = eap_sm_calculateTimeout( sm, sm->retransCount, sm->eap_if.eapSRTT, sm->eap_if.eapRTTVAR, sm->methodTimeout); } SM_STATE(EAP, RETRANSMIT2) { SM_ENTRY(EAP, RETRANSMIT2); sm->retransCount++; if (sm->retransCount <= sm->MaxRetrans && sm->lastReqData) { if (eap_copy_buf(&sm->eap_if.eapReqData, sm->lastReqData) == 0) sm->eap_if.eapReq = TRUE; } } SM_STATE(EAP, RECEIVED2) { SM_ENTRY(EAP, RECEIVED2); /* parse rxResp, respId, respMethod */ eap_sm_parseEapResp(sm, sm->eap_if.eapRespData); } SM_STATE(EAP, DISCARD2) { SM_ENTRY(EAP, DISCARD2); sm->eap_if.eapResp = FALSE; sm->eap_if.eapNoReq = TRUE; } SM_STATE(EAP, SEND_REQUEST2) { SM_ENTRY(EAP, SEND_REQUEST2); sm->retransCount = 0; if (sm->eap_if.eapReqData) { if (eap_copy_buf(&sm->lastReqData, sm->eap_if.eapReqData) == 0) { sm->eap_if.eapResp = FALSE; sm->eap_if.eapReq = TRUE; } else { sm->eap_if.eapResp = FALSE; sm->eap_if.eapReq = FALSE; } } else { wpa_printf(MSG_INFO, "EAP: SEND_REQUEST2 - no eapReqData"); sm->eap_if.eapResp = FALSE; sm->eap_if.eapReq = FALSE; sm->eap_if.eapNoReq = TRUE; } } SM_STATE(EAP, AAA_REQUEST) { SM_ENTRY(EAP, AAA_REQUEST); if (sm->eap_if.eapRespData == NULL) { wpa_printf(MSG_INFO, "EAP: AAA_REQUEST - no eapRespData"); return; } /* * if (respMethod == IDENTITY) * aaaIdentity = eapRespData * This is already taken care of by the EAP-Identity method which * stores the identity into sm->identity. */ eap_copy_buf(&sm->eap_if.aaaEapRespData, sm->eap_if.eapRespData); } SM_STATE(EAP, AAA_RESPONSE) { SM_ENTRY(EAP, AAA_RESPONSE); eap_copy_buf(&sm->eap_if.eapReqData, sm->eap_if.aaaEapReqData); sm->currentId = eap_sm_getId(sm->eap_if.eapReqData); sm->methodTimeout = sm->eap_if.aaaMethodTimeout; } SM_STATE(EAP, AAA_IDLE) { SM_ENTRY(EAP, AAA_IDLE); sm->eap_if.aaaFail = FALSE; sm->eap_if.aaaSuccess = FALSE; sm->eap_if.aaaEapReq = FALSE; sm->eap_if.aaaEapNoReq = FALSE; sm->eap_if.aaaEapResp = TRUE; } SM_STATE(EAP, TIMEOUT_FAILURE2) { SM_ENTRY(EAP, TIMEOUT_FAILURE2); sm->eap_if.eapTimeout = TRUE; } SM_STATE(EAP, FAILURE2) { SM_ENTRY(EAP, FAILURE2); eap_copy_buf(&sm->eap_if.eapReqData, sm->eap_if.aaaEapReqData); sm->eap_if.eapFail = TRUE; } SM_STATE(EAP, SUCCESS2) { SM_ENTRY(EAP, SUCCESS2); eap_copy_buf(&sm->eap_if.eapReqData, sm->eap_if.aaaEapReqData); sm->eap_if.eapKeyAvailable = sm->eap_if.aaaEapKeyAvailable; if (sm->eap_if.aaaEapKeyAvailable) { EAP_COPY(&sm->eap_if.eapKeyData, sm->eap_if.aaaEapKeyData); } else { bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen); sm->eap_if.eapKeyData = NULL; sm->eap_if.eapKeyDataLen = 0; } sm->eap_if.eapSuccess = TRUE; /* * Start reauthentication with identity request even though we know the * previously used identity. This is needed to get reauthentication * started properly. */ sm->start_reauth = TRUE; } SM_STEP(EAP) { if (sm->eap_if.eapRestart && sm->eap_if.portEnabled) SM_ENTER_GLOBAL(EAP, INITIALIZE); else if (!sm->eap_if.portEnabled) SM_ENTER_GLOBAL(EAP, DISABLED); else if (sm->num_rounds > EAP_MAX_AUTH_ROUNDS) { if (sm->num_rounds == EAP_MAX_AUTH_ROUNDS + 1) { wpa_printf(MSG_DEBUG, "EAP: more than %d " "authentication rounds - abort", EAP_MAX_AUTH_ROUNDS); sm->num_rounds++; SM_ENTER_GLOBAL(EAP, FAILURE); } } else switch (sm->EAP_state) { case EAP_INITIALIZE: if (sm->backend_auth) { if (!sm->rxResp) SM_ENTER(EAP, SELECT_ACTION); else if (sm->rxResp && (sm->respMethod == EAP_TYPE_NAK || (sm->respMethod == EAP_TYPE_EXPANDED && sm->respVendor == EAP_VENDOR_IETF && sm->respVendorMethod == EAP_TYPE_NAK))) SM_ENTER(EAP, NAK); else SM_ENTER(EAP, PICK_UP_METHOD); } else { SM_ENTER(EAP, SELECT_ACTION); } break; case EAP_PICK_UP_METHOD: if (sm->currentMethod == EAP_TYPE_NONE) { SM_ENTER(EAP, SELECT_ACTION); } else { SM_ENTER(EAP, METHOD_RESPONSE); } break; case EAP_DISABLED: if (sm->eap_if.portEnabled) SM_ENTER(EAP, INITIALIZE); break; case EAP_IDLE: if (sm->eap_if.retransWhile == 0) SM_ENTER(EAP, RETRANSMIT); else if (sm->eap_if.eapResp) SM_ENTER(EAP, RECEIVED); break; case EAP_RETRANSMIT: if (sm->retransCount > sm->MaxRetrans) SM_ENTER(EAP, TIMEOUT_FAILURE); else SM_ENTER(EAP, IDLE); break; case EAP_RECEIVED: if (sm->rxResp && (sm->respId == sm->currentId) && (sm->respMethod == EAP_TYPE_NAK || (sm->respMethod == EAP_TYPE_EXPANDED && sm->respVendor == EAP_VENDOR_IETF && sm->respVendorMethod == EAP_TYPE_NAK)) && (sm->methodState == METHOD_PROPOSED)) SM_ENTER(EAP, NAK); else if (sm->rxResp && (sm->respId == sm->currentId) && ((sm->respMethod == sm->currentMethod) || (sm->respMethod == EAP_TYPE_EXPANDED && sm->respVendor == EAP_VENDOR_IETF && sm->respVendorMethod == sm->currentMethod))) SM_ENTER(EAP, INTEGRITY_CHECK); else { wpa_printf(MSG_DEBUG, "EAP: RECEIVED->DISCARD: " "rxResp=%d respId=%d currentId=%d " "respMethod=%d currentMethod=%d", sm->rxResp, sm->respId, sm->currentId, sm->respMethod, sm->currentMethod); eap_log_msg(sm, "Discard received EAP message"); SM_ENTER(EAP, DISCARD); } break; case EAP_DISCARD: SM_ENTER(EAP, IDLE); break; case EAP_SEND_REQUEST: SM_ENTER(EAP, IDLE); break; case EAP_INTEGRITY_CHECK: if (sm->ignore) SM_ENTER(EAP, DISCARD); else SM_ENTER(EAP, METHOD_RESPONSE); break; case EAP_METHOD_REQUEST: if (sm->m == NULL) { /* * This transition is not mentioned in RFC 4137, but it * is needed to handle cleanly a case where EAP method * initialization fails. */ SM_ENTER(EAP, FAILURE); break; } SM_ENTER(EAP, SEND_REQUEST); break; case EAP_METHOD_RESPONSE: /* * Note: Mechanism to allow EAP methods to wait while going * through pending processing is an extension to RFC 4137 * which only defines the transits to SELECT_ACTION and * METHOD_REQUEST from this METHOD_RESPONSE state. */ if (sm->methodState == METHOD_END) SM_ENTER(EAP, SELECT_ACTION); else if (sm->method_pending == METHOD_PENDING_WAIT) { wpa_printf(MSG_DEBUG, "EAP: Method has pending " "processing - wait before proceeding to " "METHOD_REQUEST state"); } else if (sm->method_pending == METHOD_PENDING_CONT) { wpa_printf(MSG_DEBUG, "EAP: Method has completed " "pending processing - reprocess pending " "EAP message"); sm->method_pending = METHOD_PENDING_NONE; SM_ENTER(EAP, METHOD_RESPONSE); } else SM_ENTER(EAP, METHOD_REQUEST); break; case EAP_PROPOSE_METHOD: /* * Note: Mechanism to allow EAP methods to wait while going * through pending processing is an extension to RFC 4137 * which only defines the transit to METHOD_REQUEST from this * PROPOSE_METHOD state. */ if (sm->method_pending == METHOD_PENDING_WAIT) { wpa_printf(MSG_DEBUG, "EAP: Method has pending " "processing - wait before proceeding to " "METHOD_REQUEST state"); if (sm->user_eap_method_index > 0) sm->user_eap_method_index--; } else if (sm->method_pending == METHOD_PENDING_CONT) { wpa_printf(MSG_DEBUG, "EAP: Method has completed " "pending processing - reprocess pending " "EAP message"); sm->method_pending = METHOD_PENDING_NONE; SM_ENTER(EAP, PROPOSE_METHOD); } else SM_ENTER(EAP, METHOD_REQUEST); break; case EAP_NAK: SM_ENTER(EAP, SELECT_ACTION); break; case EAP_SELECT_ACTION: if (sm->decision == DECISION_FAILURE) SM_ENTER(EAP, FAILURE); else if (sm->decision == DECISION_SUCCESS) SM_ENTER(EAP, SUCCESS); else if (sm->decision == DECISION_PASSTHROUGH) SM_ENTER(EAP, INITIALIZE_PASSTHROUGH); else SM_ENTER(EAP, PROPOSE_METHOD); break; case EAP_TIMEOUT_FAILURE: break; case EAP_FAILURE: break; case EAP_SUCCESS: break; case EAP_INITIALIZE_PASSTHROUGH: if (sm->currentId == -1) SM_ENTER(EAP, AAA_IDLE); else SM_ENTER(EAP, AAA_REQUEST); break; case EAP_IDLE2: if (sm->eap_if.eapResp) SM_ENTER(EAP, RECEIVED2); else if (sm->eap_if.retransWhile == 0) SM_ENTER(EAP, RETRANSMIT2); break; case EAP_RETRANSMIT2: if (sm->retransCount > sm->MaxRetrans) SM_ENTER(EAP, TIMEOUT_FAILURE2); else SM_ENTER(EAP, IDLE2); break; case EAP_RECEIVED2: if (sm->rxResp && (sm->respId == sm->currentId)) SM_ENTER(EAP, AAA_REQUEST); else SM_ENTER(EAP, DISCARD2); break; case EAP_DISCARD2: SM_ENTER(EAP, IDLE2); break; case EAP_SEND_REQUEST2: SM_ENTER(EAP, IDLE2); break; case EAP_AAA_REQUEST: SM_ENTER(EAP, AAA_IDLE); break; case EAP_AAA_RESPONSE: SM_ENTER(EAP, SEND_REQUEST2); break; case EAP_AAA_IDLE: if (sm->eap_if.aaaFail) SM_ENTER(EAP, FAILURE2); else if (sm->eap_if.aaaSuccess) SM_ENTER(EAP, SUCCESS2); else if (sm->eap_if.aaaEapReq) SM_ENTER(EAP, AAA_RESPONSE); else if (sm->eap_if.aaaTimeout) SM_ENTER(EAP, TIMEOUT_FAILURE2); break; case EAP_TIMEOUT_FAILURE2: break; case EAP_FAILURE2: break; case EAP_SUCCESS2: break; } } static int eap_sm_calculateTimeout(struct eap_sm *sm, int retransCount, int eapSRTT, int eapRTTVAR, int methodTimeout) { int rto, i; if (methodTimeout) { /* * EAP method (either internal or through AAA server, provided * timeout hint. Use that as-is as a timeout for retransmitting * the EAP request if no response is received. */ wpa_printf(MSG_DEBUG, "EAP: retransmit timeout %d seconds " "(from EAP method hint)", methodTimeout); return methodTimeout; } /* * RFC 3748 recommends algorithms described in RFC 2988 for estimation * of the retransmission timeout. This should be implemented once * round-trip time measurements are available. For nowm a simple * backoff mechanism is used instead if there are no EAP method * specific hints. * * SRTT = smoothed round-trip time * RTTVAR = round-trip time variation * RTO = retransmission timeout */ /* * RFC 2988, 2.1: before RTT measurement, set RTO to 3 seconds for * initial retransmission and then double the RTO to provide back off * per 5.5. Limit the maximum RTO to 20 seconds per RFC 3748, 4.3 * modified RTOmax. */ rto = 3; for (i = 0; i < retransCount; i++) { rto *= 2; if (rto >= 20) { rto = 20; break; } } wpa_printf(MSG_DEBUG, "EAP: retransmit timeout %d seconds " "(from dynamic back off; retransCount=%d)", rto, retransCount); return rto; } static void eap_sm_parseEapResp(struct eap_sm *sm, const struct wpabuf *resp) { const struct eap_hdr *hdr; size_t plen; /* parse rxResp, respId, respMethod */ sm->rxResp = FALSE; sm->respId = -1; sm->respMethod = EAP_TYPE_NONE; sm->respVendor = EAP_VENDOR_IETF; sm->respVendorMethod = EAP_TYPE_NONE; if (resp == NULL || wpabuf_len(resp) < sizeof(*hdr)) { wpa_printf(MSG_DEBUG, "EAP: parseEapResp: invalid resp=%p " "len=%lu", resp, resp ? (unsigned long) wpabuf_len(resp) : 0); return; } hdr = wpabuf_head(resp); plen = be_to_host16(hdr->length); if (plen > wpabuf_len(resp)) { wpa_printf(MSG_DEBUG, "EAP: Ignored truncated EAP-Packet " "(len=%lu plen=%lu)", (unsigned long) wpabuf_len(resp), (unsigned long) plen); return; } sm->respId = hdr->identifier; if (hdr->code == EAP_CODE_RESPONSE) sm->rxResp = TRUE; if (plen > sizeof(*hdr)) { u8 *pos = (u8 *) (hdr + 1); sm->respMethod = *pos++; if (sm->respMethod == EAP_TYPE_EXPANDED) { if (plen < sizeof(*hdr) + 8) { wpa_printf(MSG_DEBUG, "EAP: Ignored truncated " "expanded EAP-Packet (plen=%lu)", (unsigned long) plen); return; } sm->respVendor = WPA_GET_BE24(pos); pos += 3; sm->respVendorMethod = WPA_GET_BE32(pos); } } wpa_printf(MSG_DEBUG, "EAP: parseEapResp: rxResp=%d respId=%d " "respMethod=%u respVendor=%u respVendorMethod=%u", sm->rxResp, sm->respId, sm->respMethod, sm->respVendor, sm->respVendorMethod); } static int eap_sm_getId(const struct wpabuf *data) { const struct eap_hdr *hdr; if (data == NULL || wpabuf_len(data) < sizeof(*hdr)) return -1; hdr = wpabuf_head(data); wpa_printf(MSG_DEBUG, "EAP: getId: id=%d", hdr->identifier); return hdr->identifier; } static struct wpabuf * eap_sm_buildSuccess(struct eap_sm *sm, u8 id) { struct wpabuf *msg; struct eap_hdr *resp; wpa_printf(MSG_DEBUG, "EAP: Building EAP-Success (id=%d)", id); msg = wpabuf_alloc(sizeof(*resp)); if (msg == NULL) return NULL; resp = wpabuf_put(msg, sizeof(*resp)); resp->code = EAP_CODE_SUCCESS; resp->identifier = id; resp->length = host_to_be16(sizeof(*resp)); return msg; } static struct wpabuf * eap_sm_buildFailure(struct eap_sm *sm, u8 id) { struct wpabuf *msg; struct eap_hdr *resp; wpa_printf(MSG_DEBUG, "EAP: Building EAP-Failure (id=%d)", id); msg = wpabuf_alloc(sizeof(*resp)); if (msg == NULL) return NULL; resp = wpabuf_put(msg, sizeof(*resp)); resp->code = EAP_CODE_FAILURE; resp->identifier = id; resp->length = host_to_be16(sizeof(*resp)); return msg; } static int eap_sm_nextId(struct eap_sm *sm, int id) { if (id < 0) { /* RFC 3748 Ch 4.1: recommended to initialize Identifier with a * random number */ id = rand() & 0xff; if (id != sm->lastId) return id; } return (id + 1) & 0xff; } /** * eap_sm_process_nak - Process EAP-Response/Nak * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * @nak_list: Nak list (allowed methods) from the supplicant * @len: Length of nak_list in bytes * * This function is called when EAP-Response/Nak is received from the * supplicant. This can happen for both phase 1 and phase 2 authentications. */ void eap_sm_process_nak(struct eap_sm *sm, const u8 *nak_list, size_t len) { int i; size_t j; if (sm->user == NULL) return; wpa_printf(MSG_MSGDUMP, "EAP: processing NAK (current EAP method " "index %d)", sm->user_eap_method_index); wpa_hexdump(MSG_MSGDUMP, "EAP: configured methods", (u8 *) sm->user->methods, EAP_MAX_METHODS * sizeof(sm->user->methods[0])); wpa_hexdump(MSG_MSGDUMP, "EAP: list of methods supported by the peer", nak_list, len); i = sm->user_eap_method_index; while (i < EAP_MAX_METHODS && (sm->user->methods[i].vendor != EAP_VENDOR_IETF || sm->user->methods[i].method != EAP_TYPE_NONE)) { if (sm->user->methods[i].vendor != EAP_VENDOR_IETF) goto not_found; for (j = 0; j < len; j++) { if (nak_list[j] == sm->user->methods[i].method) { break; } } if (j < len) { /* found */ i++; continue; } not_found: /* not found - remove from the list */ if (i + 1 < EAP_MAX_METHODS) { os_memmove(&sm->user->methods[i], &sm->user->methods[i + 1], (EAP_MAX_METHODS - i - 1) * sizeof(sm->user->methods[0])); } sm->user->methods[EAP_MAX_METHODS - 1].vendor = EAP_VENDOR_IETF; sm->user->methods[EAP_MAX_METHODS - 1].method = EAP_TYPE_NONE; } wpa_hexdump(MSG_MSGDUMP, "EAP: new list of configured methods", (u8 *) sm->user->methods, EAP_MAX_METHODS * sizeof(sm->user->methods[0])); } static void eap_sm_Policy_update(struct eap_sm *sm, const u8 *nak_list, size_t len) { if (nak_list == NULL || sm == NULL || sm->user == NULL) return; if (sm->user->phase2) { wpa_printf(MSG_DEBUG, "EAP: EAP-Nak received after Phase2 user" " info was selected - reject"); sm->decision = DECISION_FAILURE; return; } eap_sm_process_nak(sm, nak_list, len); } static EapType eap_sm_Policy_getNextMethod(struct eap_sm *sm, int *vendor) { EapType next; int idx = sm->user_eap_method_index; /* In theory, there should be no problems with starting * re-authentication with something else than EAP-Request/Identity and * this does indeed work with wpa_supplicant. However, at least Funk * Supplicant seemed to ignore re-auth if it skipped * EAP-Request/Identity. * Re-auth sets currentId == -1, so that can be used here to select * whether Identity needs to be requested again. */ if (sm->identity == NULL || sm->currentId == -1) { *vendor = EAP_VENDOR_IETF; next = EAP_TYPE_IDENTITY; sm->update_user = TRUE; } else if (sm->user && idx < EAP_MAX_METHODS && (sm->user->methods[idx].vendor != EAP_VENDOR_IETF || sm->user->methods[idx].method != EAP_TYPE_NONE)) { *vendor = sm->user->methods[idx].vendor; next = sm->user->methods[idx].method; sm->user_eap_method_index++; } else { *vendor = EAP_VENDOR_IETF; next = EAP_TYPE_NONE; } wpa_printf(MSG_DEBUG, "EAP: getNextMethod: vendor %d type %d", *vendor, next); return next; } static int eap_sm_Policy_getDecision(struct eap_sm *sm) { if (!sm->eap_server && sm->identity && !sm->start_reauth) { wpa_printf(MSG_DEBUG, "EAP: getDecision: -> PASSTHROUGH"); return DECISION_PASSTHROUGH; } if (sm->m && sm->currentMethod != EAP_TYPE_IDENTITY && sm->m->isSuccess(sm, sm->eap_method_priv)) { wpa_printf(MSG_DEBUG, "EAP: getDecision: method succeeded -> " "SUCCESS"); sm->update_user = TRUE; return DECISION_SUCCESS; } if (sm->m && sm->m->isDone(sm, sm->eap_method_priv) && !sm->m->isSuccess(sm, sm->eap_method_priv)) { wpa_printf(MSG_DEBUG, "EAP: getDecision: method failed -> " "FAILURE"); sm->update_user = TRUE; return DECISION_FAILURE; } if ((sm->user == NULL || sm->update_user) && sm->identity && !sm->start_reauth) { /* * Allow Identity method to be started once to allow identity * selection hint to be sent from the authentication server, * but prevent a loop of Identity requests by only allowing * this to happen once. */ int id_req = 0; if (sm->user && sm->currentMethod == EAP_TYPE_IDENTITY && sm->user->methods[0].vendor == EAP_VENDOR_IETF && sm->user->methods[0].method == EAP_TYPE_IDENTITY) id_req = 1; if (eap_user_get(sm, sm->identity, sm->identity_len, 0) != 0) { wpa_printf(MSG_DEBUG, "EAP: getDecision: user not " "found from database -> FAILURE"); return DECISION_FAILURE; } if (id_req && sm->user && sm->user->methods[0].vendor == EAP_VENDOR_IETF && sm->user->methods[0].method == EAP_TYPE_IDENTITY) { wpa_printf(MSG_DEBUG, "EAP: getDecision: stop " "identity request loop -> FAILURE"); sm->update_user = TRUE; return DECISION_FAILURE; } sm->update_user = FALSE; } sm->start_reauth = FALSE; if (sm->user && sm->user_eap_method_index < EAP_MAX_METHODS && (sm->user->methods[sm->user_eap_method_index].vendor != EAP_VENDOR_IETF || sm->user->methods[sm->user_eap_method_index].method != EAP_TYPE_NONE)) { wpa_printf(MSG_DEBUG, "EAP: getDecision: another method " "available -> CONTINUE"); return DECISION_CONTINUE; } if (sm->identity == NULL || sm->currentId == -1) { wpa_printf(MSG_DEBUG, "EAP: getDecision: no identity known " "yet -> CONTINUE"); return DECISION_CONTINUE; } wpa_printf(MSG_DEBUG, "EAP: getDecision: no more methods available -> " "FAILURE"); return DECISION_FAILURE; } static Boolean eap_sm_Policy_doPickUp(struct eap_sm *sm, EapType method) { return method == EAP_TYPE_IDENTITY ? TRUE : FALSE; } /** * eap_server_sm_step - Step EAP server state machine * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * Returns: 1 if EAP state was changed or 0 if not * * This function advances EAP state machine to a new state to match with the * current variables. This should be called whenever variables used by the EAP * state machine have changed. */ int eap_server_sm_step(struct eap_sm *sm) { int res = 0; do { sm->changed = FALSE; SM_STEP_RUN(EAP); if (sm->changed) res = 1; } while (sm->changed); return res; } static void eap_user_free(struct eap_user *user) { if (user == NULL) return; bin_clear_free(user->password, user->password_len); user->password = NULL; os_free(user); } /** * eap_server_sm_init - Allocate and initialize EAP server state machine * @eapol_ctx: Context data to be used with eapol_cb calls * @eapol_cb: Pointer to EAPOL callback functions * @conf: EAP configuration * Returns: Pointer to the allocated EAP state machine or %NULL on failure * * This function allocates and initializes an EAP state machine. */ struct eap_sm * eap_server_sm_init(void *eapol_ctx, struct eapol_callbacks *eapol_cb, struct eap_config *conf) { struct eap_sm *sm; sm = os_zalloc(sizeof(*sm)); if (sm == NULL) return NULL; sm->eapol_ctx = eapol_ctx; sm->eapol_cb = eapol_cb; sm->MaxRetrans = 5; /* RFC 3748: max 3-5 retransmissions suggested */ sm->ssl_ctx = conf->ssl_ctx; sm->msg_ctx = conf->msg_ctx; sm->eap_sim_db_priv = conf->eap_sim_db_priv; sm->backend_auth = conf->backend_auth; sm->eap_server = conf->eap_server; if (conf->pac_opaque_encr_key) { sm->pac_opaque_encr_key = os_malloc(16); if (sm->pac_opaque_encr_key) { os_memcpy(sm->pac_opaque_encr_key, conf->pac_opaque_encr_key, 16); } } if (conf->eap_fast_a_id) { sm->eap_fast_a_id = os_malloc(conf->eap_fast_a_id_len); if (sm->eap_fast_a_id) { os_memcpy(sm->eap_fast_a_id, conf->eap_fast_a_id, conf->eap_fast_a_id_len); sm->eap_fast_a_id_len = conf->eap_fast_a_id_len; } } if (conf->eap_fast_a_id_info) sm->eap_fast_a_id_info = os_strdup(conf->eap_fast_a_id_info); sm->eap_fast_prov = conf->eap_fast_prov; sm->pac_key_lifetime = conf->pac_key_lifetime; sm->pac_key_refresh_time = conf->pac_key_refresh_time; sm->eap_sim_aka_result_ind = conf->eap_sim_aka_result_ind; sm->tnc = conf->tnc; sm->wps = conf->wps; if (conf->assoc_wps_ie) sm->assoc_wps_ie = wpabuf_dup(conf->assoc_wps_ie); if (conf->assoc_p2p_ie) sm->assoc_p2p_ie = wpabuf_dup(conf->assoc_p2p_ie); if (conf->peer_addr) os_memcpy(sm->peer_addr, conf->peer_addr, ETH_ALEN); sm->fragment_size = conf->fragment_size; sm->pwd_group = conf->pwd_group; sm->pbc_in_m1 = conf->pbc_in_m1; sm->server_id = conf->server_id; sm->server_id_len = conf->server_id_len; #ifdef CONFIG_TESTING_OPTIONS sm->tls_test_flags = conf->tls_test_flags; #endif /* CONFIG_TESTING_OPTIONS */ wpa_printf(MSG_DEBUG, "EAP: Server state machine created"); return sm; } /** * eap_server_sm_deinit - Deinitialize and free an EAP server state machine * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * * This function deinitializes EAP state machine and frees all allocated * resources. */ void eap_server_sm_deinit(struct eap_sm *sm) { if (sm == NULL) return; wpa_printf(MSG_DEBUG, "EAP: Server state machine removed"); if (sm->m && sm->eap_method_priv) sm->m->reset(sm, sm->eap_method_priv); wpabuf_free(sm->eap_if.eapReqData); bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen); wpabuf_free(sm->lastReqData); wpabuf_free(sm->eap_if.eapRespData); os_free(sm->identity); os_free(sm->pac_opaque_encr_key); os_free(sm->eap_fast_a_id); os_free(sm->eap_fast_a_id_info); wpabuf_free(sm->eap_if.aaaEapReqData); wpabuf_free(sm->eap_if.aaaEapRespData); bin_clear_free(sm->eap_if.aaaEapKeyData, sm->eap_if.aaaEapKeyDataLen); eap_user_free(sm->user); wpabuf_free(sm->assoc_wps_ie); wpabuf_free(sm->assoc_p2p_ie); os_free(sm); } /** * eap_sm_notify_cached - Notify EAP state machine of cached PMK * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * * This function is called when PMKSA caching is used to skip EAP * authentication. */ void eap_sm_notify_cached(struct eap_sm *sm) { if (sm == NULL) return; sm->EAP_state = EAP_SUCCESS; } /** * eap_sm_pending_cb - EAP state machine callback for a pending EAP request * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * * This function is called when data for a pending EAP-Request is received. */ void eap_sm_pending_cb(struct eap_sm *sm) { if (sm == NULL) return; wpa_printf(MSG_DEBUG, "EAP: Callback for pending request received"); if (sm->method_pending == METHOD_PENDING_WAIT) sm->method_pending = METHOD_PENDING_CONT; } /** * eap_sm_method_pending - Query whether EAP method is waiting for pending data * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * Returns: 1 if method is waiting for pending data or 0 if not */ int eap_sm_method_pending(struct eap_sm *sm) { if (sm == NULL) return 0; return sm->method_pending == METHOD_PENDING_WAIT; } /** * eap_get_identity - Get the user identity (from EAP-Response/Identity) * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * @len: Buffer for returning identity length * Returns: Pointer to the user identity or %NULL if not available */ const u8 * eap_get_identity(struct eap_sm *sm, size_t *len) { *len = sm->identity_len; return sm->identity; } /** * eap_get_interface - Get pointer to EAP-EAPOL interface data * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * Returns: Pointer to the EAP-EAPOL interface data */ struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm) { return &sm->eap_if; } /** * eap_server_clear_identity - Clear EAP identity information * @sm: Pointer to EAP state machine allocated with eap_server_sm_init() * * This function can be used to clear the EAP identity information in the EAP * server context. This allows the EAP/Identity method to be used again after * EAPOL-Start or EAPOL-Logoff. */ void eap_server_clear_identity(struct eap_sm *sm) { os_free(sm->identity); sm->identity = NULL; }