text: /*
   * EAP peer method: EAP-TTLS (RFC 5281)
   * Copyright (c) 2004-2011, Jouni Malinen <j@w1.fi>
   *
   * This software may be distributed under the terms of the BSD license.
   * See README for more details.
   */
  
  #include "includes.h"
  
  #include "common.h"
  #include "crypto/ms_funcs.h"
  #include "crypto/sha1.h"
  #include "crypto/tls.h"
  #include "eap_common/chap.h"
  #include "eap_common/eap_ttls.h"
  #include "mschapv2.h"
  #include "eap_i.h"
  #include "eap_tls_common.h"
  #include "eap_config.h"
  
  #define EAP_TTLS_VERSION 0
  
  static void eap_ttls_deinit(struct eap_sm *sm, void *priv);
  
  struct eap_ttls_data {
  	struct eap_ssl_data ssl;
  
  	int ttls_version;
  
  	const struct eap_method *phase2_method;
  	void *phase2_priv;
  	int phase2_success;
  	int phase2_start;
  
  	enum phase2_types {
  		EAP_TTLS_PHASE2_EAP,
  		EAP_TTLS_PHASE2_MSCHAPV2,
  		EAP_TTLS_PHASE2_MSCHAP,
  		EAP_TTLS_PHASE2_PAP,
  		EAP_TTLS_PHASE2_CHAP
  	} phase2_type;
  	struct eap_method_type phase2_eap_type;
  	struct eap_method_type *phase2_eap_types;
  	size_t num_phase2_eap_types;
  
  	u8 auth_response[MSCHAPV2_AUTH_RESPONSE_LEN];
  	int auth_response_valid;
  	u8 master_key[MSCHAPV2_MASTER_KEY_LEN];	/* MSCHAPv2 master key */
  	u8 ident;
  	int resuming;				/* starting a resumed session */
  	int reauth;					/* reauthentication */
  	u8 *key_data;
  	u8 *session_id;
  	size_t id_len;
  
  	struct wpabuf *pending_phase2_req;
  
  #ifdef EAP_TNC
  	int ready_for_tnc;
  	int tnc_started;
  #endif							/* EAP_TNC */
  };
  
  static void *eap_ttls_init(struct eap_sm *sm)
  {
  	struct eap_ttls_data *data;
  	struct eap_peer_config *config = eap_get_config(sm);
  	char *selected;
  
  	data = os_zalloc(sizeof(*data));
  	if (data == NULL) {
  		return NULL;
  	}
  	data->ttls_version = EAP_TTLS_VERSION;
  	selected = "EAP";
  	data->phase2_type = EAP_TTLS_PHASE2_EAP;
  
  	if (config && config->phase2) {
  		if (os_strstr(config->phase2, "autheap=")) {
  			selected = "EAP";
  			data->phase2_type = EAP_TTLS_PHASE2_EAP;
  		} else if (os_strstr(config->phase2, "auth=MSCHAPV2")) {
  			selected = "MSCHAPV2";
  			data->phase2_type = EAP_TTLS_PHASE2_MSCHAPV2;
  		} else if (os_strstr(config->phase2, "auth=MSCHAP")) {
  			selected = "MSCHAP";
  			data->phase2_type = EAP_TTLS_PHASE2_MSCHAP;
  		} else if (os_strstr(config->phase2, "auth=PAP")) {
  			selected = "PAP";
  			data->phase2_type = EAP_TTLS_PHASE2_PAP;
  		} else if (os_strstr(config->phase2, "auth=CHAP")) {
  			selected = "CHAP";
  			data->phase2_type = EAP_TTLS_PHASE2_CHAP;
  		}
  	}
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase2 type: %s", selected);
  
  	if (data->phase2_type == EAP_TTLS_PHASE2_EAP) {
  		if (eap_peer_select_phase2_methods(config, "autheap=", &data->phase2_eap_types, &data->num_phase2_eap_types)
  			< 0) {
  			eap_ttls_deinit(sm, data);
  			return NULL;
  		}
  
  		data->phase2_eap_type.vendor = EAP_VENDOR_IETF;
  		data->phase2_eap_type.method = EAP_TYPE_NONE;
  	}
  
  	if (eap_peer_tls_ssl_init(sm, &data->ssl, config, EAP_TYPE_TTLS)) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Failed to initialize SSL.");
  		eap_ttls_deinit(sm, data);
  		return NULL;
  	}
  
  	return data;
  }
  
  static void eap_ttls_phase2_eap_deinit(struct eap_sm *sm, struct eap_ttls_data *data)
  {
  	if (data->phase2_priv && data->phase2_method) {
  		data->phase2_method->deinit(sm, data->phase2_priv);
  		data->phase2_method = NULL;
  		data->phase2_priv = NULL;
  	}
  }
  
  static void eap_ttls_free_key(struct eap_ttls_data *data)
  {
  	if (data->key_data) {
  		bin_clear_free(data->key_data, EAP_TLS_KEY_LEN + EAP_EMSK_LEN);
  		data->key_data = NULL;
  	}
  }
  
  static void eap_ttls_deinit(struct eap_sm *sm, void *priv)
  {
  	struct eap_ttls_data *data = priv;
  	if (data == NULL) {
  		return;
  	}
  	eap_ttls_phase2_eap_deinit(sm, data);
  	os_free(data->phase2_eap_types);
  	eap_peer_tls_ssl_deinit(sm, &data->ssl);
  	eap_ttls_free_key(data);
  	os_free(data->session_id);
  	wpabuf_free(data->pending_phase2_req);
  	os_free(data);
  }
  
  static u8 *eap_ttls_avp_hdr(u8 *avphdr, u32 avp_code, u32 vendor_id, int mandatory, size_t len)
  {
  	struct ttls_avp_vendor *avp;
  	u8 flags;
  	size_t hdrlen;
  
  	avp = (struct ttls_avp_vendor *)avphdr;
  	flags = mandatory ? AVP_FLAGS_MANDATORY : 0;
  	if (vendor_id) {
  		flags |= AVP_FLAGS_VENDOR;
  		hdrlen = sizeof(*avp);
  		avp->vendor_id = host_to_be32(vendor_id);
  	} else {
  		hdrlen = sizeof(struct ttls_avp);
  	}
  
  	avp->avp_code = host_to_be32(avp_code);
  	avp->avp_length = host_to_be32((flags << 24) | (u32)(hdrlen + len));
  
  	return avphdr + hdrlen;
  }
  
  static u8 *eap_ttls_avp_add(u8 *start, u8 *avphdr, u32 avp_code, u32 vendor_id, int mandatory, const u8 *data, size_t len)
  {
  	u8 *pos;
  	pos = eap_ttls_avp_hdr(avphdr, avp_code, vendor_id, mandatory, len);
  	os_memcpy(pos, data, len);
  	pos += len;
  	AVP_PAD(start, pos);
  	return pos;
  }
  
  static int eap_ttls_avp_encapsulate(struct wpabuf **resp, u32 avp_code, int mandatory)
  {
  	struct wpabuf *msg;
  	u8 *avp, *pos;
  
  	msg = wpabuf_alloc(sizeof(struct ttls_avp) + wpabuf_len(*resp) + 4);
  	if (msg == NULL) {
  		wpabuf_free(*resp);
  		*resp = NULL;
  		return -1;
  	}
  
  	avp = wpabuf_mhead(msg);
  	pos = eap_ttls_avp_hdr(avp, avp_code, 0, mandatory, wpabuf_len(*resp));
  	os_memcpy(pos, wpabuf_head(*resp), wpabuf_len(*resp));
  	pos += wpabuf_len(*resp);
  	AVP_PAD(avp, pos);
  	wpabuf_free(*resp);
  	wpabuf_put(msg, pos - avp);
  	*resp = msg;
  	return 0;
  }
  
  static int eap_ttls_v0_derive_key(struct eap_sm *sm, struct eap_ttls_data *data)
  {
  	eap_ttls_free_key(data);
  	data->key_data = eap_peer_tls_derive_key(sm, &data->ssl, "ttls keying material", EAP_TLS_KEY_LEN + EAP_EMSK_LEN);
  	if (!data->key_data) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Failed to derive key");
  		return -1;
  	}
  
  	wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: Derived key", data->key_data, EAP_TLS_KEY_LEN);
  	wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: Derived EMSK", data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
  
  	os_free(data->session_id);
  	data->session_id = eap_peer_tls_derive_session_id(sm, &data->ssl, EAP_TYPE_TTLS, &data->id_len);
  	if (data->session_id) {
  		wpa_hexdump(MSG_DEBUG, "EAP-TTLS: Derived Session-Id", data->session_id, data->id_len);
  	} else {
  		wpa_printf(MSG_ERROR, "EAP-TTLS: Failed to derive Session-Id");
  	}
  
  	return 0;
  }
  
  static u8 *eap_ttls_implicit_challenge(struct eap_sm *sm, struct eap_ttls_data *data, size_t len)
  {
  	return eap_peer_tls_derive_key(sm, &data->ssl, "ttls challenge", len);
  }
  
  static void eap_ttls_phase2_select_eap_method(struct eap_ttls_data *data, u8 method)
  {
  	size_t i;
  	for (i = 0; i < data->num_phase2_eap_types; i++) {
  		if (data->phase2_eap_types[i].vendor != EAP_VENDOR_IETF || data->phase2_eap_types[i].method != method) {
  			continue;
  		}
  
  		data->phase2_eap_type.vendor = data->phase2_eap_types[i].vendor;
  		data->phase2_eap_type.method = data->phase2_eap_types[i].method;
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Selected " "Phase 2 EAP vendor %d method %d", data->phase2_eap_type.vendor, data->phase2_eap_type.method);
  		break;
  	}
  }
  
  static int eap_ttls_phase2_eap_process(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct eap_hdr *hdr, size_t len, struct wpabuf **resp)
  {
  	struct wpabuf msg;
  	struct eap_method_ret iret;
  
  	os_memset(&iret, 0, sizeof(iret));
  	wpabuf_set(&msg, hdr, len);
  	*resp = data->phase2_method->process(sm, data->phase2_priv, &iret, &msg);
  	if ((iret.methodState == METHOD_DONE || iret.methodState == METHOD_MAY_CONT) && (iret.decision == DECISION_UNCOND_SUCC || iret.decision == DECISION_COND_SUCC || iret.decision == DECISION_FAIL)) {
  		ret->methodState = iret.methodState;
  		ret->decision = iret.decision;
  	}
  
  	return 0;
  }
  
  static int eap_ttls_phase2_request_eap_method(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct eap_hdr *hdr, size_t len, u8 method, struct wpabuf **resp)
  {
  #ifdef EAP_TNC
  	if (data->tnc_started && data->phase2_method && data->phase2_priv && method == EAP_TYPE_TNC && data->phase2_eap_type.method == EAP_TYPE_TNC) {
  		return eap_ttls_phase2_eap_process(sm, data, ret, hdr, len, resp);
  	}
  
  	if (data->ready_for_tnc && !data->tnc_started && method == EAP_TYPE_TNC) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Start TNC after completed " "EAP method");
  		data->tnc_started = 1;
  	}
  
  	if (data->tnc_started) {
  		if (data->phase2_eap_type.vendor != EAP_VENDOR_IETF || data->phase2_eap_type.method == EAP_TYPE_TNC) {
  			wpa_printf(MSG_DEBUG, "EAP-TTLS: Unexpected EAP " "type %d for TNC", method);
  			return -1;
  		}
  
  		data->phase2_eap_type.vendor = EAP_VENDOR_IETF;
  		data->phase2_eap_type.method = method;
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Selected " "Phase 2 EAP vendor %d method %d (TNC)", data->phase2_eap_type.vendor, data->phase2_eap_type.method);
  
  		if (data->phase2_type == EAP_TTLS_PHASE2_EAP) {
  			eap_ttls_phase2_eap_deinit(sm, data);
  		}
  	}
  #endif							/* EAP_TNC */
  
  	if (data->phase2_eap_type.vendor == EAP_VENDOR_IETF && data->phase2_eap_type.method == EAP_TYPE_NONE) {
  		eap_ttls_phase2_select_eap_method(data, method);
  	}
  
  	if (method != data->phase2_eap_type.method || method == EAP_TYPE_NONE) {
  		if (eap_peer_tls_phase2_nak(data->phase2_eap_types, data->num_phase2_eap_types, hdr, resp)) {
  			return -1;
  		}
  		return 0;
  	}
  
  	if (data->phase2_priv == NULL) {
  		data->phase2_method = eap_peer_get_eap_method(EAP_VENDOR_IETF, method);
  		if (data->phase2_method) {
  			sm->init_phase2 = 1;
  			data->phase2_priv = data->phase2_method->init(sm);
  			sm->init_phase2 = 0;
  		}
  	}
  	if (data->phase2_priv == NULL || data->phase2_method == NULL) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: failed to initialize " "Phase 2 EAP method %d", method);
  		return -1;
  	}
  
  	return eap_ttls_phase2_eap_process(sm, data, ret, hdr, len, resp);
  }
  
  static int eap_ttls_phase2_request_eap(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct eap_hdr *hdr, struct wpabuf **resp)
  {
  	size_t len = be_to_host16(hdr->length);
  	u8 *pos;
  	struct eap_peer_config *config = eap_get_config(sm);
  
  	if (len <= sizeof(struct eap_hdr)) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: too short " "Phase 2 request (len=%lu)", (unsigned long)len);
  		return -1;
  	}
  	pos = (u8 *)(hdr + 1);
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase 2 EAP Request: type=%d", *pos);
  	switch (*pos) {
  	case EAP_TYPE_IDENTITY:
  		*resp = eap_sm_buildIdentity(sm, hdr->identifier, 1);
  		break;
  	default:
  		if (eap_ttls_phase2_request_eap_method(sm, data, ret, hdr, len, *pos, resp) < 0) {
  			return -1;
  		}
  		break;
  	}
  
  	if (*resp == NULL && (config->pending_req_identity || config->pending_req_password || config->pending_req_otp)) {
  		return 0;
  	}
  
  	if (*resp == NULL) {
  		return -1;
  	}
  
  	wpa_hexdump_buf(MSG_DEBUG, "EAP-TTLS: AVP encapsulate EAP Response", *resp);
  	return eap_ttls_avp_encapsulate(resp, RADIUS_ATTR_EAP_MESSAGE, 1);
  }
  
  static int eap_ttls_phase2_request_mschapv2(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct wpabuf **resp)
  {
  #ifdef EAP_MSCHAPv2
  	struct wpabuf *msg;
  	u8 *buf, *pos, *challenge, *peer_challenge;
  	const u8 *identity, *password;
  	size_t identity_len, password_len;
  	int pwhash;
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase 2 MSCHAPV2 Request");
  
  	identity = eap_get_config_identity(sm, &identity_len);
  	password = eap_get_config_password2(sm, &password_len, &pwhash);
  	if (identity == NULL || password == NULL) {
  		return -1;
  	}
  
  	msg = wpabuf_alloc(identity_len + 1000);
  	if (msg == NULL) {
  		wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to allocate memory");
  		return -1;
  	}
  	pos = buf = wpabuf_mhead(msg);
  
  	/* User-Name */
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_USER_NAME, 0, 1, identity, identity_len);
  
  	/* MS-CHAP-Challenge */
  	challenge = eap_ttls_implicit_challenge(sm, data, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN + 1);
  	if (challenge == NULL) {
  		wpabuf_free(msg);
  		wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to derive " "implicit challenge");
  		return -1;
  	}
  
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_MS_CHAP_CHALLENGE, RADIUS_VENDOR_ID_MICROSOFT, 1, challenge, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN);
  
  	/* MS-CHAP2-Response */
  	pos = eap_ttls_avp_hdr(pos, RADIUS_ATTR_MS_CHAP2_RESPONSE, RADIUS_VENDOR_ID_MICROSOFT, 1, EAP_TTLS_MSCHAPV2_RESPONSE_LEN);
  	data->ident = challenge[EAP_TTLS_MSCHAPV2_CHALLENGE_LEN];
  	*pos++ = data->ident;
  	*pos++ = 0;					/* Flags */
  	if (os_get_random(pos, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN) < 0) {
  		os_free(challenge);
  		wpabuf_free(msg);
  		wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to get " "random data for peer challenge");
  		return -1;
  	}
  	peer_challenge = pos;
  	pos += EAP_TTLS_MSCHAPV2_CHALLENGE_LEN;
  	os_memset(pos, 0, 8);		/* Reserved, must be zero */
  	pos += 8;
  	if (mschapv2_derive_response(identity, identity_len, password, password_len, pwhash, challenge, peer_challenge, pos, data->auth_response, data->master_key)) {
  		os_free(challenge);
  		wpabuf_free(msg);
  		wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to derive " "response");
  		return -1;
  	}
  	data->auth_response_valid = 1;
  
  	pos += 24;
  	os_free(challenge);
  	AVP_PAD(buf, pos);
  
  	wpabuf_put(msg, pos - buf);
  	*resp = msg;
  
  	return 0;
  #else							/* EAP_MSCHAPv2 */
  	wpa_printf(MSG_ERROR, "EAP-TTLS: MSCHAPv2 not included in the build");
  	return -1;
  #endif							/* EAP_MSCHAPv2 */
  }
  
  static int eap_ttls_phase2_request_mschap(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct wpabuf **resp)
  {
  	struct wpabuf *msg;
  	u8 *buf, *pos, *challenge;
  	const u8 *identity, *password;
  	size_t identity_len, password_len;
  	int pwhash;
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase 2 MSCHAP Request");
  
  	identity = eap_get_config_identity(sm, &identity_len);
  	password = eap_get_config_password2(sm, &password_len, &pwhash);
  	if (identity == NULL || password == NULL) {
  		return -1;
  	}
  
  	msg = wpabuf_alloc(identity_len + 1000);
  	if (msg == NULL) {
  		wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAP: Failed to allocate memory");
  		return -1;
  	}
  	pos = buf = wpabuf_mhead(msg);
  
  	/* User-Name */
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_USER_NAME, 0, 1, identity, identity_len);
  
  	/* MS-CHAP-Challenge */
  	challenge = eap_ttls_implicit_challenge(sm, data, EAP_TTLS_MSCHAP_CHALLENGE_LEN + 1);
  	if (challenge == NULL) {
  		wpabuf_free(msg);
  		wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAP: Failed to derive " "implicit challenge");
  		return -1;
  	}
  
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_MS_CHAP_CHALLENGE, RADIUS_VENDOR_ID_MICROSOFT, 1, challenge, EAP_TTLS_MSCHAP_CHALLENGE_LEN);
  
  	/* MS-CHAP-Response */
  	pos = eap_ttls_avp_hdr(pos, RADIUS_ATTR_MS_CHAP_RESPONSE, RADIUS_VENDOR_ID_MICROSOFT, 1, EAP_TTLS_MSCHAP_RESPONSE_LEN);
  	data->ident = challenge[EAP_TTLS_MSCHAP_CHALLENGE_LEN];
  	*pos++ = data->ident;
  	*pos++ = 1;					/* Flags: Use NT style passwords */
  	os_memset(pos, 0, 24);		/* LM-Response */
  	pos += 24;
  	if (pwhash) {
  		challenge_response(challenge, password, pos);	/* NT-Response */
  		wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: MSCHAP password hash", password, 16);
  	} else {
  		nt_challenge_response(challenge, password, password_len, pos);	/* NT-Response */
  		wpa_hexdump_ascii_key(MSG_DEBUG, "EAP-TTLS: MSCHAP password", password, password_len);
  	}
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: MSCHAP implicit challenge", challenge, EAP_TTLS_MSCHAP_CHALLENGE_LEN);
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: MSCHAP response", pos, 24);
  	pos += 24;
  	os_free(challenge);
  	AVP_PAD(buf, pos);
  
  	wpabuf_put(msg, pos - buf);
  	*resp = msg;
  
  	/* EAP-TTLS/MSCHAP does not provide tunneled success
  	 * notification, so assume that Phase2 succeeds. */
  	ret->methodState = METHOD_DONE;
  	ret->decision = DECISION_COND_SUCC;
  
  	return 0;
  }
  
  static int eap_ttls_phase2_request_pap(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct wpabuf **resp)
  {
  	struct wpabuf *msg;
  	u8 *buf, *pos;
  	size_t pad;
  	const u8 *identity, *password;
  	size_t identity_len, password_len;
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase 2 PAP Request");
  
  	identity = eap_get_config_identity(sm, &identity_len);
  	password = eap_get_config_password(sm, &password_len);
  	if (identity == NULL || password == NULL) {
  		return -1;
  	}
  
  	msg = wpabuf_alloc(identity_len + password_len + 100);
  	if (msg == NULL) {
  		wpa_printf(MSG_ERROR, "EAP-TTLS/PAP: Failed to allocate memory");
  		return -1;
  	}
  	pos = buf = wpabuf_mhead(msg);
  
  	/* User-Name */
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_USER_NAME, 0, 1, identity, identity_len);
  
  	/* User-Password; in RADIUS, this is encrypted, but EAP-TTLS encrypts
  	 * the data, so no separate encryption is used in the AVP itself.
  	 * However, the password is padded to obfuscate its length. */
  	pad = password_len == 0 ? 16 : (16 - (password_len & 15)) & 15;
  	pos = eap_ttls_avp_hdr(pos, RADIUS_ATTR_USER_PASSWORD, 0, 1, password_len + pad);
  	os_memcpy(pos, password, password_len);
  	pos += password_len;
  	os_memset(pos, 0, pad);
  	pos += pad;
  	AVP_PAD(buf, pos);
  
  	wpabuf_put(msg, pos - buf);
  	*resp = msg;
  
  	/* EAP-TTLS/PAP does not provide tunneled success notification,
  	 * so assume that Phase2 succeeds. */
  	ret->methodState = METHOD_DONE;
  	ret->decision = DECISION_COND_SUCC;
  
  	return 0;
  }
  
  static int eap_ttls_phase2_request_chap(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct wpabuf **resp)
  {
  	struct wpabuf *msg;
  	u8 *buf, *pos, *challenge;
  	const u8 *identity, *password;
  	size_t identity_len, password_len;
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase 2 CHAP Request");
  
  	identity = eap_get_config_identity(sm, &identity_len);
  	password = eap_get_config_password(sm, &password_len);
  	if (identity == NULL || password == NULL) {
  		return -1;
  	}
  
  	msg = wpabuf_alloc(identity_len + 1000);
  	if (msg == NULL) {
  		wpa_printf(MSG_ERROR, "EAP-TTLS/CHAP: Failed to allocate memory");
  		return -1;
  	}
  	pos = buf = wpabuf_mhead(msg);
  
  	/* User-Name */
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_USER_NAME, 0, 1, identity, identity_len);
  
  	/* CHAP-Challenge */
  	challenge = eap_ttls_implicit_challenge(sm, data, EAP_TTLS_CHAP_CHALLENGE_LEN + 1);
  	if (challenge == NULL) {
  		wpabuf_free(msg);
  		wpa_printf(MSG_ERROR, "EAP-TTLS/CHAP: Failed to derive " "implicit challenge");
  		return -1;
  	}
  
  	pos = eap_ttls_avp_add(buf, pos, RADIUS_ATTR_CHAP_CHALLENGE, 0, 1, challenge, EAP_TTLS_CHAP_CHALLENGE_LEN);
  
  	/* CHAP-Password */
  	pos = eap_ttls_avp_hdr(pos, RADIUS_ATTR_CHAP_PASSWORD, 0, 1, 1 + EAP_TTLS_CHAP_PASSWORD_LEN);
  	data->ident = challenge[EAP_TTLS_CHAP_CHALLENGE_LEN];
  	*pos++ = data->ident;
  
  	/* MD5(Ident + Password + Challenge) */
  	chap_md5(data->ident, password, password_len, challenge, EAP_TTLS_CHAP_CHALLENGE_LEN, pos);
  
  	wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: CHAP username", identity, identity_len);
  	wpa_hexdump_ascii_key(MSG_DEBUG, "EAP-TTLS: CHAP password", password, password_len);
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: CHAP implicit challenge", challenge, EAP_TTLS_CHAP_CHALLENGE_LEN);
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: CHAP password", pos, EAP_TTLS_CHAP_PASSWORD_LEN);
  	pos += EAP_TTLS_CHAP_PASSWORD_LEN;
  	os_free(challenge);
  	AVP_PAD(buf, pos);
  
  	wpabuf_put(msg, pos - buf);
  	*resp = msg;
  
  	/* EAP-TTLS/CHAP does not provide tunneled success
  	 * notification, so assume that Phase2 succeeds. */
  	ret->methodState = METHOD_DONE;
  	ret->decision = DECISION_COND_SUCC;
  
  	return 0;
  }
  
  static int eap_ttls_phase2_request(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct eap_hdr *hdr, struct wpabuf **resp)
  {
  	int res = 0;
  	size_t len;
  	enum phase2_types phase2_type = data->phase2_type;
  
  #ifdef EAP_TNC
  	if (data->tnc_started) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Processing TNC");
  		phase2_type = EAP_TTLS_PHASE2_EAP;
  	}
  #endif							/* EAP_TNC */
  
  	if (phase2_type == EAP_TTLS_PHASE2_MSCHAPV2 || phase2_type == EAP_TTLS_PHASE2_MSCHAP || phase2_type == EAP_TTLS_PHASE2_PAP || phase2_type == EAP_TTLS_PHASE2_CHAP) {
  		if (eap_get_config_identity(sm, &len) == NULL) {
  			wpa_printf(MSG_INFO, "EAP-TTLS: Identity not configured");
  			eap_sm_request_identity(sm);
  			if (eap_get_config_password(sm, &len) == NULL) {
  				eap_sm_request_password(sm);
  			}
  			return 0;
  		}
  
  		if (eap_get_config_password(sm, &len) == NULL) {
  			wpa_printf(MSG_INFO, "EAP-TTLS: Password not configured");
  			eap_sm_request_password(sm);
  			return 0;
  		}
  	}
  
  	switch (phase2_type) {
  	case EAP_TTLS_PHASE2_EAP:
  		res = eap_ttls_phase2_request_eap(sm, data, ret, hdr, resp);
  		break;
  	case EAP_TTLS_PHASE2_MSCHAPV2:
  		res = eap_ttls_phase2_request_mschapv2(sm, data, ret, resp);
  		break;
  	case EAP_TTLS_PHASE2_MSCHAP:
  		res = eap_ttls_phase2_request_mschap(sm, data, ret, resp);
  		break;
  	case EAP_TTLS_PHASE2_PAP:
  		res = eap_ttls_phase2_request_pap(sm, data, ret, resp);
  		break;
  	case EAP_TTLS_PHASE2_CHAP:
  		res = eap_ttls_phase2_request_chap(sm, data, ret, resp);
  		break;
  	default:
  		wpa_printf(MSG_ERROR, "EAP-TTLS: Phase 2 - Unknown");
  		res = -1;
  		break;
  	}
  
  	if (res < 0) {
  		ret->methodState = METHOD_DONE;
  		ret->decision = DECISION_FAIL;
  	}
  
  	return res;
  }
  
  struct ttls_parse_avp {
  	u8 *mschapv2;
  	u8 *eapdata;
  	size_t eap_len;
  	int mschapv2_error;
  };
  
  static int eap_ttls_parse_attr_eap(const u8 *dpos, size_t dlen, struct ttls_parse_avp *parse)
  {
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: AVP - EAP Message");
  	if (parse->eapdata == NULL) {
  		parse->eapdata = os_malloc(dlen);
  		if (parse->eapdata == NULL) {
  			wpa_printf(MSG_WARNING, "EAP-TTLS: Failed to allocate " "memory for Phase 2 EAP data");
  			return -1;
  		}
  		os_memcpy(parse->eapdata, dpos, dlen);
  		parse->eap_len = dlen;
  	} else {
  		u8 *neweap = os_realloc(parse->eapdata, parse->eap_len + dlen);
  		if (neweap == NULL) {
  			wpa_printf(MSG_WARNING, "EAP-TTLS: Failed to allocate " "memory for Phase 2 EAP data");
  			return -1;
  		}
  		os_memcpy(neweap + parse->eap_len, dpos, dlen);
  		parse->eapdata = neweap;
  		parse->eap_len += dlen;
  	}
  
  	return 0;
  }
  
  static int eap_ttls_parse_avp(u8 *pos, size_t left, struct ttls_parse_avp *parse)
  {
  	struct ttls_avp *avp;
  	u32 avp_code, avp_length, vendor_id = 0;
  	u8 avp_flags, *dpos;
  	size_t dlen;
  
  	avp = (struct ttls_avp *)pos;
  	avp_code = be_to_host32(avp->avp_code);
  	avp_length = be_to_host32(avp->avp_length);
  	avp_flags = (avp_length >> 24) & 0xff;
  	avp_length &= 0xffffff;
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: AVP: code=%d flags=0x%02x " "length=%d", (int)avp_code, avp_flags, (int)avp_length);
  
  	if (avp_length > left) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: AVP overflow " "(len=%d, left=%lu) - dropped", (int)avp_length, (unsigned long)left);
  		return -1;
  	}
  
  	if (avp_length < sizeof(*avp)) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: Invalid AVP length %d", avp_length);
  		return -1;
  	}
  
  	dpos = (u8 *)(avp + 1);
  	dlen = avp_length - sizeof(*avp);
  	if (avp_flags & AVP_FLAGS_VENDOR) {
  		if (dlen < 4) {
  			wpa_printf(MSG_WARNING, "EAP-TTLS: Vendor AVP " "underflow");
  			return -1;
  		}
  		vendor_id = WPA_GET_BE32(dpos);
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: AVP vendor_id %d", (int)vendor_id);
  		dpos += 4;
  		dlen -= 4;
  	}
  
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: AVP data", dpos, dlen);
  
  	if (vendor_id == 0 && avp_code == RADIUS_ATTR_EAP_MESSAGE) {
  		if (eap_ttls_parse_attr_eap(dpos, dlen, parse) < 0) {
  			return -1;
  		}
  	} else if (vendor_id == 0 && avp_code == RADIUS_ATTR_REPLY_MESSAGE) {
  		/* This is an optional message that can be displayed to
  		 * the user. */
  		wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: AVP - Reply-Message", dpos, dlen);
  	} else if (vendor_id == RADIUS_VENDOR_ID_MICROSOFT && avp_code == RADIUS_ATTR_MS_CHAP2_SUCCESS) {
  		wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: MS-CHAP2-Success", dpos, dlen);
  		if (dlen != 43) {
  			wpa_printf(MSG_WARNING, "EAP-TTLS: Unexpected " "MS-CHAP2-Success length " "(len=%lu, expected 43)", (unsigned long)dlen);
  			return -1;
  		}
  		parse->mschapv2 = dpos;
  	} else if (vendor_id == RADIUS_VENDOR_ID_MICROSOFT && avp_code == RADIUS_ATTR_MS_CHAP_ERROR) {
  		wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: MS-CHAP-Error", dpos, dlen);
  		parse->mschapv2_error = 1;
  	} else if (avp_flags & AVP_FLAGS_MANDATORY) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: Unsupported mandatory AVP " "code %d vendor_id %d - dropped", (int)avp_code, (int)vendor_id);
  		return -1;
  	} else {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Ignoring unsupported AVP " "code %d vendor_id %d", (int)avp_code, (int)vendor_id);
  	}
  
  	return avp_length;
  }
  
  static int eap_ttls_parse_avps(struct wpabuf *in_decrypted, struct ttls_parse_avp *parse)
  {
  	u8 *pos;
  	size_t left, pad;
  	int avp_length;
  
  	pos = wpabuf_mhead(in_decrypted);
  	left = wpabuf_len(in_decrypted);
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: Decrypted Phase 2 AVPs", pos, left);
  	if (left < sizeof(struct ttls_avp)) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: Too short Phase 2 AVP frame" " len=%lu expected %lu or more - dropped", (unsigned long)left, (unsigned long)sizeof(struct ttls_avp));
  		return -1;
  	}
  
  	/* Parse AVPs */
  	os_memset(parse, 0, sizeof(*parse));
  
  	while (left > 0) {
  		avp_length = eap_ttls_parse_avp(pos, left, parse);
  		if (avp_length < 0) {
  			return -1;
  		}
  
  		pad = (4 - (avp_length & 3)) & 3;
  		pos += avp_length + pad;
  		if (left < avp_length + pad) {
  			left = 0;
  		} else {
  			left -= avp_length + pad;
  		}
  	}
  
  	return 0;
  }
  
  static u8 *eap_ttls_fake_identity_request(void)
  {
  	struct eap_hdr *hdr;
  	u8 *buf;
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: empty data in beginning of " "Phase 2 - use fake EAP-Request Identity");
  	buf = os_malloc(sizeof(*hdr) + 1);
  	if (buf == NULL) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: failed to allocate " "memory for fake EAP-Identity Request");
  		return NULL;
  	}
  
  	hdr = (struct eap_hdr *)buf;
  	hdr->code = EAP_CODE_REQUEST;
  	hdr->identifier = 0;
  	hdr->length = host_to_be16(sizeof(*hdr) + 1);
  	buf[sizeof(*hdr)] = EAP_TYPE_IDENTITY;
  
  	return buf;
  }
  
  static int eap_ttls_encrypt_response(struct eap_sm *sm, struct eap_ttls_data *data, struct wpabuf *resp, u8 identifier, struct wpabuf **out_data)
  {
  	if (resp == NULL) {
  		return 0;
  	}
  
  	wpa_hexdump_buf_key(MSG_DEBUG, "EAP-TTLS: Encrypting Phase 2 data", resp);
  	if (eap_peer_tls_encrypt(sm, &data->ssl, EAP_TYPE_TTLS, data->ttls_version, identifier, resp, out_data)) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Failed to encrypt a Phase 2 " "frame");
  		wpabuf_free(resp);
  		return -1;
  	}
  	wpabuf_free(resp);
  
  	return 0;
  }
  
  static int eap_ttls_process_phase2_eap(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct ttls_parse_avp *parse, struct wpabuf **resp)
  {
  	struct eap_hdr *hdr;
  	size_t len;
  
  	if (parse->eapdata == NULL) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: No EAP Message in the " "packet - dropped");
  		return -1;
  	}
  
  	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: Phase 2 EAP", parse->eapdata, parse->eap_len);
  	hdr = (struct eap_hdr *)parse->eapdata;
  
  	if (parse->eap_len < sizeof(*hdr)) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: Too short Phase 2 EAP " "frame (len=%lu, expected %lu or more) - dropped", (unsigned long)parse->eap_len, (unsigned long)sizeof(*hdr));
  		return -1;
  	}
  	len = be_to_host16(hdr->length);
  	if (len > parse->eap_len) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Length mismatch in Phase 2 " "EAP frame (EAP hdr len=%lu, EAP data len in " "AVP=%lu)", (unsigned long)len, (unsigned long)parse->eap_len);
  		return -1;
  	}
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: received Phase 2: code=%d " "identifier=%d length=%lu", hdr->code, hdr->identifier, (unsigned long)len);
  	switch (hdr->code) {
  	case EAP_CODE_REQUEST:
  		if (eap_ttls_phase2_request(sm, data, ret, hdr, resp)) {
  			wpa_printf(MSG_INFO, "EAP-TTLS: Phase2 Request " "processing failed");
  			return -1;
  		}
  		break;
  	default:
  		wpa_printf(MSG_INFO, "EAP-TTLS: Unexpected code=%d in " "Phase 2 EAP header", hdr->code);
  		return -1;
  	}
  
  	return 0;
  }
  
  static int eap_ttls_process_phase2_mschapv2(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct ttls_parse_avp *parse)
  {
  #ifdef EAP_MSCHAPv2
  	if (parse->mschapv2_error) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Received " "MS-CHAP-Error - failed");
  		ret->methodState = METHOD_DONE;
  		ret->decision = DECISION_FAIL;
  		/* Reply with empty data to ACK error */
  		return 1;
  	}
  
  	if (parse->mschapv2 == NULL) {
  #ifdef EAP_TNC
  		if (data->phase2_success && parse->eapdata) {
  			/*
  			 * Allow EAP-TNC to be started after successfully
  			 * completed MSCHAPV2.
  			 */
  			return 1;
  		}
  #endif							/* EAP_TNC */
  		wpa_printf(MSG_WARNING, "EAP-TTLS: no MS-CHAP2-Success AVP " "received for Phase2 MSCHAPV2");
  		return -1;
  	}
  	if (parse->mschapv2[0] != data->ident) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: Ident mismatch for Phase 2 " "MSCHAPV2 (received Ident 0x%02x, expected 0x%02x)", parse->mschapv2[0], data->ident);
  		return -1;
  	}
  	if (!data->auth_response_valid || mschapv2_verify_auth_response(data->auth_response, parse->mschapv2 + 1, 42)) {
  		wpa_printf(MSG_WARNING, "EAP-TTLS: Invalid authenticator " "response in Phase 2 MSCHAPV2 success request");
  		return -1;
  	}
  
  	wpa_printf(MSG_INFO, "EAP-TTLS: Phase 2 MSCHAPV2 " "authentication succeeded");
  	ret->methodState = METHOD_DONE;
  	ret->decision = DECISION_UNCOND_SUCC;
  	data->phase2_success = 1;
  
  	/*
  	 * Reply with empty data; authentication server will reply
  	 * with EAP-Success after this.
  	 */
  	return 1;
  #else							/* EAP_MSCHAPv2 */
  	wpa_printf(MSG_ERROR, "EAP-TTLS: MSCHAPv2 not included in the build");
  	return -1;
  #endif							/* EAP_MSCHAPv2 */
  }
  
  #ifdef EAP_TNC
  static int eap_ttls_process_tnc_start(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, struct ttls_parse_avp *parse, struct wpabuf **resp)
  {
  	/* TNC uses inner EAP method after non-EAP TTLS phase 2. */
  	if (parse->eapdata == NULL) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Phase 2 received " "unexpected tunneled data (no EAP)");
  		return -1;
  	}
  
  	if (!data->ready_for_tnc) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Phase 2 received " "EAP after non-EAP, but not ready for TNC");
  		return -1;
  	}
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: Start TNC after completed " "non-EAP method");
  	data->tnc_started = 1;
  
  	if (eap_ttls_process_phase2_eap(sm, data, ret, parse, resp) < 0) {
  		return -1;
  	}
  
  	return 0;
  }
  #endif							/* EAP_TNC */
  
  static int eap_ttls_process_decrypted(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, u8 identifier, struct ttls_parse_avp *parse, struct wpabuf *in_decrypted, struct wpabuf **out_data)
  {
  	struct wpabuf *resp = NULL;
  	struct eap_peer_config *config = eap_get_config(sm);
  	int res;
  	enum phase2_types phase2_type = data->phase2_type;
  
  #ifdef EAP_TNC
  	if (data->tnc_started) {
  		phase2_type = EAP_TTLS_PHASE2_EAP;
  	}
  #endif							/* EAP_TNC */
  
  	switch (phase2_type) {
  	case EAP_TTLS_PHASE2_EAP:
  		if (eap_ttls_process_phase2_eap(sm, data, ret, parse, &resp) < 0) {
  			return -1;
  		}
  		break;
  	case EAP_TTLS_PHASE2_MSCHAPV2:
  		res = eap_ttls_process_phase2_mschapv2(sm, data, ret, parse);
  #ifdef EAP_TNC
  		if (res == 1 && parse->eapdata && data->phase2_success) {
  			/*
  			 * TNC may be required as the next
  			 * authentication method within the tunnel.
  			 */
  			ret->methodState = METHOD_MAY_CONT;
  			data->ready_for_tnc = 1;
  			if (eap_ttls_process_tnc_start(sm, data, ret, parse, &resp) == 0) {
  				break;
  			}
  		}
  #endif							/* EAP_TNC */
  		return res;
  	case EAP_TTLS_PHASE2_MSCHAP:
  	case EAP_TTLS_PHASE2_PAP:
  	case EAP_TTLS_PHASE2_CHAP:
  #ifdef EAP_TNC
  		if (eap_ttls_process_tnc_start(sm, data, ret, parse, &resp) < 0) {
  			return -1;
  		}
  		break;
  #else							/* EAP_TNC */
  		/* EAP-TTLS/{MSCHAP,PAP,CHAP} should not send any TLS tunneled
  		 * requests to the supplicant */
  		wpa_printf(MSG_INFO, "EAP-TTLS: Phase 2 received unexpected " "tunneled data");
  		return -1;
  #endif							/* EAP_TNC */
  	}
  
  	if (resp) {
  		if (eap_ttls_encrypt_response(sm, data, resp, identifier, out_data) < 0) {
  			return -1;
  		}
  	} else if (config->pending_req_identity || config->pending_req_password || config->pending_req_otp || config->pending_req_new_password) {
  		wpabuf_free(data->pending_phase2_req);
  		data->pending_phase2_req = wpabuf_dup(in_decrypted);
  	}
  
  	return 0;
  }
  
  static int eap_ttls_implicit_identity_request(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, u8 identifier, struct wpabuf **out_data)
  {
  	int retval = 0;
  	struct eap_hdr *hdr;
  	struct wpabuf *resp;
  
  	hdr = (struct eap_hdr *)eap_ttls_fake_identity_request();
  	if (hdr == NULL) {
  		ret->methodState = METHOD_DONE;
  		ret->decision = DECISION_FAIL;
  		return -1;
  	}
  
  	resp = NULL;
  	if (eap_ttls_phase2_request(sm, data, ret, hdr, &resp)) {
  		wpa_printf(MSG_INFO, "EAP-TTLS: Phase2 Request " "processing failed");
  		retval = -1;
  	} else {
  		struct eap_peer_config *config = eap_get_config(sm);
  		if (resp == NULL && (config->pending_req_identity || config->pending_req_password || config->pending_req_otp || config->pending_req_new_password)) {
  			/*
  			 * Use empty buffer to force implicit request
  			 * processing when EAP request is re-processed after
  			 * user input.
  			 */
  			wpabuf_free(data->pending_phase2_req);
  			data->pending_phase2_req = wpabuf_alloc(0);
  		}
  
  		retval = eap_ttls_encrypt_response(sm, data, resp, identifier, out_data);
  	}
  
  	os_free(hdr);
  
  	if (retval < 0) {
  		ret->methodState = METHOD_DONE;
  		ret->decision = DECISION_FAIL;
  	}
  
  	return retval;
  }
  
  static int eap_ttls_phase2_start(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, u8 identifier, struct wpabuf **out_data)
  {
  	data->phase2_start = 0;
  
  	/*
  	 * EAP-TTLS does not use Phase2 on fast re-auth; this must be done only
  	 * if TLS part was indeed resuming a previous session. Most
  	 * Authentication Servers terminate EAP-TTLS before reaching this
  	 * point, but some do not. Make wpa_supplicant stop phase 2 here, if
  	 * needed.
  	 */
  	if (data->reauth && tls_connection_resumed(sm->ssl_ctx, data->ssl.conn)) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Session resumption - " "skip phase 2");
  		*out_data = eap_peer_tls_build_ack(identifier, EAP_TYPE_TTLS, data->ttls_version);
  		ret->methodState = METHOD_DONE;
  		ret->decision = DECISION_UNCOND_SUCC;
  		data->phase2_success = 1;
  		return 0;
  	}
  
  	return eap_ttls_implicit_identity_request(sm, data, ret, identifier, out_data);
  }
  
  static int eap_ttls_decrypt(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, u8 identifier, const struct wpabuf *in_data, struct wpabuf **out_data)
  {
  	struct wpabuf *in_decrypted = NULL;
  	int retval = 0;
  	struct ttls_parse_avp parse;
  
  	os_memset(&parse, 0, sizeof(parse));
  
  	wpa_printf(MSG_DEBUG, "EAP-TTLS: received %lu bytes encrypted data for" " Phase 2", in_data ? (unsigned long)wpabuf_len(in_data) : 0);
  
  	if (data->pending_phase2_req) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Pending Phase 2 request - " "skip decryption and use old data");
  		/* Clear TLS reassembly state. */
  		eap_peer_tls_reset_input(&data->ssl);
  
  		in_decrypted = data->pending_phase2_req;
  		data->pending_phase2_req = NULL;
  		if (wpabuf_len(in_decrypted) == 0) {
  			wpabuf_free(in_decrypted);
  			return eap_ttls_implicit_identity_request(sm, data, ret, identifier, out_data);
  		}
  		goto continue_req;
  	}
  
  	if ((in_data == NULL || wpabuf_len(in_data) == 0) && data->phase2_start) {
  		return eap_ttls_phase2_start(sm, data, ret, identifier, out_data);
  	}
  
  	if (in_data == NULL || wpabuf_len(in_data) == 0) {
  		/* Received TLS ACK - requesting more fragments */
  		return eap_peer_tls_encrypt(sm, &data->ssl, EAP_TYPE_TTLS, data->ttls_version, identifier, NULL, out_data);
  	}
  
  	retval = eap_peer_tls_decrypt(sm, &data->ssl, in_data, &in_decrypted);
  	if (retval) {
  		goto done;
  	}
  
  continue_req:
  	data->phase2_start = 0;
  
  	if (eap_ttls_parse_avps(in_decrypted, &parse) < 0) {
  		retval = -1;
  		goto done;
  	}
  
  	retval = eap_ttls_process_decrypted(sm, data, ret, identifier, &parse, in_decrypted, out_data);
  
  done:
  	wpabuf_free(in_decrypted);
  	os_free(parse.eapdata);
  
  	if (retval < 0) {
  		ret->methodState = METHOD_DONE;
  		ret->decision = DECISION_FAIL;
  	}
  
  	return retval;
  }
  
  static int eap_ttls_process_handshake(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret, u8 identifier, const struct wpabuf *in_data, struct wpabuf **out_data)
  {
  	int res;
  
  	res = eap_peer_tls_process_helper(sm, &data->ssl, EAP_TYPE_TTLS, data->ttls_version, identifier, in_data, out_data);
  
  	if (tls_connection_established(sm->ssl_ctx, data->ssl.conn)) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: TLS done, proceed to " "Phase 2");
  		if (data->resuming) {
  			wpa_printf(MSG_DEBUG, "EAP-TTLS: fast reauth - may " "skip Phase 2");
  			ret->decision = DECISION_COND_SUCC;
  			ret->methodState = METHOD_MAY_CONT;
  		}
  		data->phase2_start = 1;
  		eap_ttls_v0_derive_key(sm, data);
  
  		if (*out_data == NULL || wpabuf_len(*out_data) == 0) {
  			if (eap_ttls_decrypt(sm, data, ret, identifier, NULL, out_data)) {
  				wpa_printf(MSG_WARNING, "EAP-TTLS: " "failed to process early " "start for Phase 2");
  			}
  			res = 0;
  		}
  		data->resuming = 0;
  	}
  
  	if (res == 2) {
  		/*
  		 * Application data included in the handshake message.
  		 */
  		wpabuf_free(data->pending_phase2_req);
  		data->pending_phase2_req = *out_data;
  		*out_data = NULL;
  		res = eap_ttls_decrypt(sm, data, ret, identifier, in_data, out_data);
  	}
  
  	return res;
  }
  
  static void eap_ttls_check_auth_status(struct eap_sm *sm, struct eap_ttls_data *data, struct eap_method_ret *ret)
  {
  	if (ret->methodState == METHOD_DONE) {
  		ret->allowNotifications = FALSE;
  		if (ret->decision == DECISION_UNCOND_SUCC || ret->decision == DECISION_COND_SUCC) {
  			wpa_printf(MSG_DEBUG, "EAP-TTLS: Authentication " "completed successfully");
  			data->phase2_success = 1;
  #ifdef EAP_TNC
  			if (!data->ready_for_tnc && !data->tnc_started) {
  				/*
  				 * TNC may be required as the next
  				 * authentication method within the tunnel.
  				 */
  				ret->methodState = METHOD_MAY_CONT;
  				data->ready_for_tnc = 1;
  			}
  #endif							/* EAP_TNC */
  		}
  	} else if (ret->methodState == METHOD_MAY_CONT && (ret->decision == DECISION_UNCOND_SUCC || ret->decision == DECISION_COND_SUCC)) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Authentication " "completed successfully (MAY_CONT)");
  		data->phase2_success = 1;
  	}
  }
  
  static struct wpabuf *eap_ttls_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret, const struct wpabuf *reqData)
  {
  	size_t left;
  	int res;
  	u8 flags, id;
  	struct wpabuf *resp;
  	const u8 *pos;
  	struct eap_ttls_data *data = priv;
  	struct wpabuf msg;
  
  	pos = eap_peer_tls_process_init(sm, &data->ssl, EAP_TYPE_TTLS, ret, reqData, &left, &flags);
  	if (pos == NULL) {
  		return NULL;
  	}
  	id = eap_get_id(reqData);
  
  	if (flags & EAP_TLS_FLAGS_START) {
  		wpa_printf(MSG_DEBUG, "EAP-TTLS: Start (server ver=%d, own " "ver=%d)", flags & EAP_TLS_VERSION_MASK, data->ttls_version);
  
  		/* RFC 5281, Ch. 9.2:
  		 * "This packet MAY contain additional information in the form
  		 * of AVPs, which may provide useful hints to the client"
  		 * For now, ignore any potential extra data.
  		 */
  		left = 0;
  	}
  
  	wpabuf_set(&msg, pos, left);
  
  	resp = NULL;
  	if (tls_connection_established(sm->ssl_ctx, data->ssl.conn) && !data->resuming) {
  		res = eap_ttls_decrypt(sm, data, ret, id, &msg, &resp);
  	} else {
  		res = eap_ttls_process_handshake(sm, data, ret, id, &msg, &resp);
  	}
  
  	eap_ttls_check_auth_status(sm, data, ret);
  
  	/* FIX: what about res == -1? Could just move all error processing into
  	 * the other functions and get rid of this res==1 case here. */
  	if (res == 1) {
  		wpabuf_free(resp);
  		return eap_peer_tls_build_ack(id, EAP_TYPE_TTLS, data->ttls_version);
  	}
  	return resp;
  }
  
  static Boolean eap_ttls_has_reauth_data(struct eap_sm *sm, void *priv)
  {
  	struct eap_ttls_data *data = priv;
  	return tls_connection_established(sm->ssl_ctx, data->ssl.conn) && data->phase2_success;
  }
  
  static void eap_ttls_deinit_for_reauth(struct eap_sm *sm, void *priv)
  {
  	struct eap_ttls_data *data = priv;
  	wpabuf_free(data->pending_phase2_req);
  	data->pending_phase2_req = NULL;
  #ifdef EAP_TNC
  	data->ready_for_tnc = 0;
  	data->tnc_started = 0;
  #endif							/* EAP_TNC */
  }
  
  static void *eap_ttls_init_for_reauth(struct eap_sm *sm, void *priv)
  {
  	struct eap_ttls_data *data = priv;
  	eap_ttls_free_key(data);
  	os_free(data->session_id);
  	data->session_id = NULL;
  	if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
  		os_free(data);
  		return NULL;
  	}
  	if (data->phase2_priv && data->phase2_method && data->phase2_method->init_for_reauth) {
  		data->phase2_method->init_for_reauth(sm, data->phase2_priv);
  	}
  	data->phase2_start = 0;
  	data->phase2_success = 0;
  	data->resuming = 1;
  	data->reauth = 1;
  	return priv;
  }
  
  static int eap_ttls_get_status(struct eap_sm *sm, void *priv, char *buf, size_t buflen, int verbose)
  {
  	struct eap_ttls_data *data = priv;
  	int len, ret;
  
  	len = eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
  	ret = os_snprintf(buf + len, buflen - len, "EAP-TTLSv%d Phase2 method=", data->ttls_version);
  	if (os_snprintf_error(buflen - len, ret)) {
  		return len;
  	}
  	len += ret;
  	switch (data->phase2_type) {
  	case EAP_TTLS_PHASE2_EAP:
  		ret = os_snprintf(buf + len, buflen - len, "EAP-%s\n", data->phase2_method ? data->phase2_method->name : "?");
  		break;
  	case EAP_TTLS_PHASE2_MSCHAPV2:
  		ret = os_snprintf(buf + len, buflen - len, "MSCHAPV2\n");
  		break;
  	case EAP_TTLS_PHASE2_MSCHAP:
  		ret = os_snprintf(buf + len, buflen - len, "MSCHAP\n");
  		break;
  	case EAP_TTLS_PHASE2_PAP:
  		ret = os_snprintf(buf + len, buflen - len, "PAP\n");
  		break;
  	case EAP_TTLS_PHASE2_CHAP:
  		ret = os_snprintf(buf + len, buflen - len, "CHAP\n");
  		break;
  	default:
  		ret = 0;
  		break;
  	}
  	if (os_snprintf_error(buflen - len, ret)) {
  		return len;
  	}
  	len += ret;
  
  	return len;
  }
  
  static Boolean eap_ttls_isKeyAvailable(struct eap_sm *sm, void *priv)
  {
  	struct eap_ttls_data *data = priv;
  	return data->key_data != NULL && data->phase2_success;
  }
  
  static u8 *eap_ttls_getKey(struct eap_sm *sm, void *priv, size_t *len)
  {
  	struct eap_ttls_data *data = priv;
  	u8 *key;
  
  	if (data->key_data == NULL || !data->phase2_success) {
  		return NULL;
  	}
  
  	key = os_malloc(EAP_TLS_KEY_LEN);
  	if (key == NULL) {
  		return NULL;
  	}
  
  	*len = EAP_TLS_KEY_LEN;
  	os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
  
  	return key;
  }
  
  static u8 *eap_ttls_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
  {
  	struct eap_ttls_data *data = priv;
  	u8 *id;
  
  	if (data->session_id == NULL || !data->phase2_success) {
  		return NULL;
  	}
  
  	id = os_malloc(data->id_len);
  	if (id == NULL) {
  		return NULL;
  	}
  
  	*len = data->id_len;
  	os_memcpy(id, data->session_id, data->id_len);
  
  	return id;
  }
  
  static u8 *eap_ttls_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
  {
  	struct eap_ttls_data *data = priv;
  	u8 *key;
  
  	if (data->key_data == NULL) {
  		return NULL;
  	}
  
  	key = os_malloc(EAP_EMSK_LEN);
  	if (key == NULL) {
  		return NULL;
  	}
  
  	*len = EAP_EMSK_LEN;
  	os_memcpy(key, data->key_data + EAP_TLS_KEY_LEN, EAP_EMSK_LEN);
  
  	return key;
  }
  
  int eap_peer_ttls_register(void)
  {
  	struct eap_method *eap;
  	int ret;
  
  	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION, EAP_VENDOR_IETF, EAP_TYPE_TTLS, "TTLS");
  	if (eap == NULL) {
  		return -1;
  	}
  
  	eap->init = eap_ttls_init;
  	eap->deinit = eap_ttls_deinit;
  	eap->process = eap_ttls_process;
  	eap->isKeyAvailable = eap_ttls_isKeyAvailable;
  	eap->getKey = eap_ttls_getKey;
  	eap->getSessionId = eap_ttls_get_session_id;
  	eap->get_status = eap_ttls_get_status;
  	eap->has_reauth_data = eap_ttls_has_reauth_data;
  	eap->deinit_for_reauth = eap_ttls_deinit_for_reauth;
  	eap->init_for_reauth = eap_ttls_init_for_reauth;
  	eap->get_emsk = eap_ttls_get_emsk;
  
  	ret = eap_peer_method_register(eap);
  	if (ret) {
  		eap_peer_method_free(eap);
  	}
  	return ret;
  }
  