eap_ttls.c

最新的Host AP 新添加了许多pcmcia 的驱动

/*
 * EAP peer method: EAP-TTLS (RFC 5281)
 * Copyright (c) 2004-2008, Jouni Malinen <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"

#include "common.h"
#include "eap_peer/eap_i.h"
#include "eap_peer/eap_tls_common.h"
#include "eap_peer/eap_config.h"
#include "ms_funcs.h"
#include "sha1.h"
#include "eap_common/chap.h"
#include "tls.h"
#include "mschapv2.h"
#include "eap_common/eap_ttls.h"


/* Maximum supported TTLS version
 * 0 = RFC 5281
 * 1 = draft-funk-eap-ttls-v1-00.txt
 */
#ifndef EAP_TTLS_VERSION
#define EAP_TTLS_VERSION 0 /* TTLSv1 implementation is not yet complete */
#endif /* EAP_TTLS_VERSION */


#define MSCHAPV2_KEY_LEN 16
#define MSCHAPV2_NT_RESPONSE_LEN 24


static void eap_ttls_deinit(struct eap_sm *sm, void *priv);


struct eap_ttls_data {
	struct eap_ssl_data ssl;
	int ssl_initialized;

	int ttls_version, force_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;

	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;
	data->force_ttls_version = -1;
	selected = "EAP";
	data->phase2_type = EAP_TTLS_PHASE2_EAP;

#if EAP_TTLS_VERSION > 0
	if (config && config->phase1) {
		const char *pos = os_strstr(config->phase1, "ttlsver=");
		if (pos) {
			data->force_ttls_version = atoi(pos + 8);
			data->ttls_version = data->force_ttls_version;
			wpa_printf(MSG_DEBUG, "EAP-TTLS: Forced TTLS version "
				   "%d", data->force_ttls_version);
		}
	}
#endif /* EAP_TTLS_VERSION */

	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_TTLS_VERSION > 0
	if (!(tls_capabilities(sm->ssl_ctx) & TLS_CAPABILITY_IA) &&
	    data->ttls_version > 0) {
		if (data->force_ttls_version > 0) {
			wpa_printf(MSG_INFO, "EAP-TTLS: Forced TTLSv%d and "
				   "TLS library does not support TLS/IA.",
				   data->force_ttls_version);
			eap_ttls_deinit(sm, data);
			return NULL;
		}
		data->ttls_version = 0;
	}
#endif /* EAP_TTLS_VERSION */

	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_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);
	if (data->ssl_initialized)
		eap_peer_tls_ssl_deinit(sm, &data->ssl);
	os_free(data->key_data);
	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) | (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;
}


#if EAP_TTLS_VERSION > 0
static int eap_ttls_ia_permute_inner_secret(struct eap_sm *sm,
					    struct eap_ttls_data *data,
					    const u8 *key, size_t key_len)
{
	u8 *buf;
	size_t buf_len;
	int ret;

	if (key) {
		buf_len = 2 + key_len;
		buf = os_malloc(buf_len);
		if (buf == NULL)
			return -1;
		WPA_PUT_BE16(buf, key_len);
		os_memcpy(buf + 2, key, key_len);
	} else {
		buf = NULL;
		buf_len = 0;
	}

	wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: Session keys for TLS/IA inner "
			"secret permutation", buf, buf_len);
	ret = tls_connection_ia_permute_inner_secret(sm->ssl_ctx,
						     data->ssl.conn,
						     buf, buf_len);
	os_free(buf);

	return ret;
}
#endif /* EAP_TTLS_VERSION */


static int eap_ttls_v0_derive_key(struct eap_sm *sm,
				  struct eap_ttls_data *data)
{
	os_free(data->key_data);
	data->key_data = eap_peer_tls_derive_key(sm, &data->ssl,
						 "ttls keying material",
						 EAP_TLS_KEY_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);

	return 0;
}


#if EAP_TTLS_VERSION > 0
static int eap_ttls_v1_derive_key(struct eap_sm *sm,
				  struct eap_ttls_data *data)
{
	struct tls_keys keys;
	u8 *rnd;

	os_free(data->key_data);
	data->key_data = NULL;

	os_memset(&keys, 0, sizeof(keys));
	if (tls_connection_get_keys(sm->ssl_ctx, data->ssl.conn, &keys) ||
	    keys.client_random == NULL || keys.server_random == NULL ||
	    keys.inner_secret == NULL) {
		wpa_printf(MSG_INFO, "EAP-TTLS: Could not get inner secret, "
			   "client random, or server random to derive keying "
			   "material");
		return -1;
	}

	rnd = os_malloc(keys.client_random_len + keys.server_random_len);
	data->key_data = os_malloc(EAP_TLS_KEY_LEN);
	if (rnd == NULL || data->key_data == NULL) {
		wpa_printf(MSG_INFO, "EAP-TTLS: No memory for key derivation");
		os_free(rnd);
		os_free(data->key_data);
		data->key_data = NULL;
		return -1;
	}
	os_memcpy(rnd, keys.client_random, keys.client_random_len);
	os_memcpy(rnd + keys.client_random_len, keys.server_random,
		  keys.server_random_len);

	if (tls_prf(keys.inner_secret, keys.inner_secret_len,
		    "ttls v1 keying material", rnd, keys.client_random_len +
		    keys.server_random_len, data->key_data, EAP_TLS_KEY_LEN)) {
		wpa_printf(MSG_DEBUG, "EAP-TTLS: Failed to derive key");
		os_free(rnd);
		os_free(data->key_data);
		data->key_data = NULL;
		return -1;
	}

	wpa_hexdump(MSG_DEBUG, "EAP-TTLS: client/server random",
		    rnd, keys.client_random_len + keys.server_random_len);
	wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: TLS/IA inner secret",
			keys.inner_secret, keys.inner_secret_len);

	os_free(rnd);

	wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: Derived key",
			data->key_data, EAP_TLS_KEY_LEN);

	return 0;
}
#endif /* EAP_TTLS_VERSION */


static u8 * eap_ttls_implicit_challenge(struct eap_sm *sm,
					struct eap_ttls_data *data, size_t len)
{
#if EAP_TTLS_VERSION > 0
	struct tls_keys keys;
	u8 *challenge, *rnd;
#endif /* EAP_TTLS_VERSION */

	if (data->ttls_version == 0) {
		return eap_peer_tls_derive_key(sm, &data->ssl,
					       "ttls challenge", len);
	}

#if EAP_TTLS_VERSION > 0

	os_memset(&keys, 0, sizeof(keys));
	if (tls_connection_get_keys(sm->ssl_ctx, data->ssl.conn, &keys) ||
	    keys.client_random == NULL || keys.server_random == NULL ||
	    keys.inner_secret == NULL) {
		wpa_printf(MSG_INFO, "EAP-TTLS: Could not get inner secret, "
			   "client random, or server random to derive "
			   "implicit challenge");
		return NULL;
	}

	rnd = os_malloc(keys.client_random_len + keys.server_random_len);
	challenge = os_malloc(len);
	if (rnd == NULL || challenge == NULL) {
		wpa_printf(MSG_INFO, "EAP-TTLS: No memory for implicit "
			   "challenge derivation");
		os_free(rnd);
		os_free(challenge);
		return NULL;
	}
	os_memcpy(rnd, keys.server_random, keys.server_random_len);
	os_memcpy(rnd + keys.server_random_len, keys.client_random,
		  keys.client_random_len);

	if (tls_prf(keys.inner_secret, keys.inner_secret_len,
		    "inner application challenge", rnd,
		    keys.client_random_len + keys.server_random_len,
		    challenge, len)) {
		wpa_printf(MSG_DEBUG, "EAP-TTLS: Failed to derive implicit "
			   "challenge");
		os_free(rnd);
		os_free(challenge);
		return NULL;
	}

	os_free(rnd);

	wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: Derived implicit challenge",
			challenge, len);

	return challenge;

#else /* EAP_TTLS_VERSION */

	return NULL;

#endif /* EAP_TTLS_VERSION */
}


static void eap_ttlsv1_phase2_eap_finish(struct eap_sm *sm,
					 struct eap_ttls_data *data,
					 struct eap_method_ret *ret)
{
#if EAP_TTLS_VERSION > 0
	if (data->ttls_version > 0) {
		const struct eap_method *m = data->phase2_method;
		void *priv = data->phase2_priv;

		/* TTLSv1 requires TLS/IA FinalPhaseFinished */
		if (ret->decision == DECISION_UNCOND_SUCC)
			ret->decision = DECISION_COND_SUCC;
		ret->methodState = METHOD_CONT;

		if (ret->decision == DECISION_COND_SUCC &&
		    m->isKeyAvailable && m->getKey &&
		    m->isKeyAvailable(sm, priv)) {
			u8 *key;
			size_t key_len;
			key = m->getKey(sm, priv, &key_len);
			if (key) {
				eap_ttls_ia_permute_inner_secret(
					sm, data, key, key_len);
				os_free(key);
			}
		}
	}
#endif /* EAP_TTLS_VERSION */
}


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;
	}