contrib/hostapd/src/eap_server/eap_server_ikev2.c

/*
 * EAP-IKEv2 server (RFC 5106)
 * Copyright (c) 2007, 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 "eap_i.h"
#include "eap_common/eap_ikev2_common.h"
#include "ikev2.h"


struct eap_ikev2_data {
	struct ikev2_initiator_data ikev2;
	enum { MSG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
	struct wpabuf *in_buf;
	struct wpabuf *out_buf;
	size_t out_used;
	size_t fragment_size;
	int keys_ready;
	u8 keymat[EAP_MSK_LEN + EAP_EMSK_LEN];
	int keymat_ok;
};


static const u8 * eap_ikev2_get_shared_secret(void *ctx, const u8 *IDr,
					      size_t IDr_len,
					      size_t *secret_len)
{
	struct eap_sm *sm = ctx;

	if (IDr == NULL) {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: No IDr received - default "
			   "to user identity from EAP-Identity");
		IDr = sm->identity;
		IDr_len = sm->identity_len;
	}

	if (eap_user_get(sm, IDr, IDr_len, 0) < 0 || sm->user == NULL ||
	    sm->user->password == NULL) {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: No user entry found");
		return NULL;
	}

	*secret_len = sm->user->password_len;
	return sm->user->password;
}


static const char * eap_ikev2_state_txt(int state)
{
	switch (state) {
	case MSG:
		return "MSG";
	case FRAG_ACK:
		return "FRAG_ACK";
	case WAIT_FRAG_ACK:
		return "WAIT_FRAG_ACK";
	case DONE:
		return "DONE";
	case FAIL:
		return "FAIL";
	default:
		return "?";
	}
}


static void eap_ikev2_state(struct eap_ikev2_data *data, int state)
{
	wpa_printf(MSG_DEBUG, "EAP-IKEV2: %s -> %s",
		   eap_ikev2_state_txt(data->state),
		   eap_ikev2_state_txt(state));
	data->state = state;
}


static void * eap_ikev2_init(struct eap_sm *sm)
{
	struct eap_ikev2_data *data;

	data = os_zalloc(sizeof(*data));
	if (data == NULL)
		return NULL;
	data->state = MSG;
	data->fragment_size = sm->fragment_size > 0 ? sm->fragment_size :
		IKEV2_FRAGMENT_SIZE;
	data->ikev2.state = SA_INIT;
	data->ikev2.peer_auth = PEER_AUTH_SECRET;
	data->ikev2.key_pad = (u8 *) os_strdup("Key Pad for EAP-IKEv2");
	if (data->ikev2.key_pad == NULL)
		goto failed;
	data->ikev2.key_pad_len = 21;

	/* TODO: make proposals configurable */
	data->ikev2.proposal.proposal_num = 1;
	data->ikev2.proposal.integ = AUTH_HMAC_SHA1_96;
	data->ikev2.proposal.prf = PRF_HMAC_SHA1;
	data->ikev2.proposal.encr = ENCR_AES_CBC;
	data->ikev2.proposal.dh = DH_GROUP2_1024BIT_MODP;

	data->ikev2.IDi = os_malloc(sm->server_id_len);
	if (data->ikev2.IDi == NULL)
		goto failed;
	os_memcpy(data->ikev2.IDi, sm->server_id, sm->server_id_len);
	data->ikev2.IDi_len = sm->server_id_len;

	data->ikev2.get_shared_secret = eap_ikev2_get_shared_secret;
	data->ikev2.cb_ctx = sm;

	return data;

failed:
	ikev2_initiator_deinit(&data->ikev2);
	os_free(data);
	return NULL;
}


static void eap_ikev2_reset(struct eap_sm *sm, void *priv)
{
	struct eap_ikev2_data *data = priv;
	wpabuf_free(data->in_buf);
	wpabuf_free(data->out_buf);
	ikev2_initiator_deinit(&data->ikev2);
	os_free(data);
}


static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data, u8 id)
{
	struct wpabuf *req;
	u8 flags;
	size_t send_len, plen, icv_len = 0;

	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Request");

	flags = 0;
	send_len = wpabuf_len(data->out_buf) - data->out_used;
	if (1 + send_len > data->fragment_size) {
		send_len = data->fragment_size - 1;
		flags |= IKEV2_FLAGS_MORE_FRAGMENTS;
		if (data->out_used == 0) {
			flags |= IKEV2_FLAGS_LENGTH_INCLUDED;
			send_len -= 4;
		}
	}

	plen = 1 + send_len;
	if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
		plen += 4;
	if (data->keys_ready) {
		const struct ikev2_integ_alg *integ;
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
			   "Data");
		flags |= IKEV2_FLAGS_ICV_INCLUDED;
		integ = ikev2_get_integ(data->ikev2.proposal.integ);
		if (integ == NULL) {
			wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
				   "transform / cannot generate ICV");
			return NULL;
		}
		icv_len = integ->hash_len;

		plen += icv_len;
	}
	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
			    EAP_CODE_REQUEST, id);
	if (req == NULL)
		return NULL;

	wpabuf_put_u8(req, flags); /* Flags */
	if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
		wpabuf_put_be32(req, wpabuf_len(data->out_buf));

	wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
			send_len);
	data->out_used += send_len;

	if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
		const u8 *msg = wpabuf_head(req);
		size_t len = wpabuf_len(req);
		ikev2_integ_hash(data->ikev2.proposal.integ,
				 data->ikev2.keys.SK_ai,
				 data->ikev2.keys.SK_integ_len,
				 msg, len, wpabuf_put(req, icv_len));
	}

	if (data->out_used == wpabuf_len(data->out_buf)) {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
			   "(message sent completely)",
			   (unsigned long) send_len);
		wpabuf_free(data->out_buf);
		data->out_buf = NULL;
		data->out_used = 0;
	} else {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
			   "(%lu more to send)", (unsigned long) send_len,
			   (unsigned long) wpabuf_len(data->out_buf) -
			   data->out_used);
		eap_ikev2_state(data, WAIT_FRAG_ACK);
	}

	return req;
}


static struct wpabuf * eap_ikev2_buildReq(struct eap_sm *sm, void *priv, u8 id)
{
	struct eap_ikev2_data *data = priv;

	switch (data->state) {
	case MSG:
		if (data->out_buf == NULL) {
			data->out_buf = ikev2_initiator_build(&data->ikev2);
			if (data->out_buf == NULL) {
				wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to "
					   "generate IKEv2 message");
				return NULL;
			}
			data->out_used = 0;
		}
		/* pass through */
	case WAIT_FRAG_ACK:
		return eap_ikev2_build_msg(data, id);
	case FRAG_ACK:
		return eap_ikev2_build_frag_ack(id, EAP_CODE_REQUEST);
	default:
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected state %d in "
			   "buildReq", data->state);
		return NULL;
	}
}


static Boolean eap_ikev2_check(struct eap_sm *sm, void *priv,
			       struct wpabuf *respData)
{
	const u8 *pos;
	size_t len;

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
			       &len);
	if (pos == NULL) {
		wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid frame");
		return TRUE;
	}

	return FALSE;
}


static int eap_ikev2_process_icv(struct eap_ikev2_data *data,
				 const struct wpabuf *respData,
				 u8 flags, const u8 *pos, const u8 **end)
{
	if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
		int icv_len = eap_ikev2_validate_icv(
			data->ikev2.proposal.integ, &data->ikev2.keys, 0,
			respData, pos, *end);
		if (icv_len < 0)
			return -1;
		/* Hide Integrity Checksum Data from further processing */
		*end -= icv_len;
	} else if (data->keys_ready) {
		wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
			   "included integrity checksum");
		return -1;
	}

	return 0;
}


static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
				  const u8 *buf, size_t len)
{
	/* Process continuation of a pending message */
	if (len > wpabuf_tailroom(data->in_buf)) {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
		eap_ikev2_state(data, FAIL);
		return -1;
	}

	wpabuf_put_data(data->in_buf, buf, len);
	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting for %lu "
		   "bytes more", (unsigned long) len,
		   (unsigned long) wpabuf_tailroom(data->in_buf));

	return 0;
}


static int eap_ikev2_process_fragment(struct eap_ikev2_data *data,
				      u8 flags, u32 message_length,
				      const u8 *buf, size_t len)
{
	/* Process a fragment that is not the last one of the message */
	if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
			   "a fragmented packet");
		return -1;
	}

	if (data->in_buf == NULL) {
		/* First fragment of the message */
		data->in_buf = wpabuf_alloc(message_length);
		if (data->in_buf == NULL) {
			wpa_printf(MSG_DEBUG, "EAP-IKEV2: No memory for "
				   "message");
			return -1;
		}
		wpabuf_put_data(data->in_buf, buf, len);
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes in first "
			   "fragment, waiting for %lu bytes more",
			   (unsigned long) len,
			   (unsigned long) wpabuf_tailroom(data->in_buf));
	}

	return 0;
}


static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
{
	if (eap_ikev2_derive_keymat(
		    data->ikev2.proposal.prf, &data->ikev2.keys,
		    data->ikev2.i_nonce, data->ikev2.i_nonce_len,
		    data->ikev2.r_nonce, data->ikev2.r_nonce_len,
		    data->keymat) < 0) {
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
			   "key material");
		return -1;
	}
	data->keymat_ok = 1;
	return 0;
}


static void eap_ikev2_process(struct eap_sm *sm, void *priv,
			      struct wpabuf *respData)
{
	struct eap_ikev2_data *data = priv;
	const u8 *start, *pos, *end;
	size_t len;
	u8 flags;
	u32 message_length = 0;
	struct wpabuf tmpbuf;

	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
			       &len);
	if (pos == NULL)
		return; /* Should not happen; message already verified */

	start = pos;
	end = start + len;

	if (len == 0) {
		/* fragment ack */
		flags = 0;
	} else
		flags = *pos++;

	if (eap_ikev2_process_icv(data, respData, flags, pos, &end) < 0) {
		eap_ikev2_state(data, FAIL);
		return;
	}

	if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
		if (end - pos < 4) {
			wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
			eap_ikev2_state(data, FAIL);
			return;
		}
		message_length = WPA_GET_BE32(pos);
		pos += 4;

		if (message_length < (u32) (end - pos)) {
			wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
				   "Length (%d; %ld remaining in this msg)",
				   message_length, (long) (end - pos));
			eap_ikev2_state(data, FAIL);
			return;
		}
	}
	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
		   "Message Length %u", flags, message_length);

	if (data->state == WAIT_FRAG_ACK) {
		if (len != 0) {
			wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
				   "in WAIT_FRAG_ACK state");
			eap_ikev2_state(data, FAIL);
			return;
		}
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
		eap_ikev2_state(data, MSG);
		return;
	}

	if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
		eap_ikev2_state(data, FAIL);
		return;
	}

	if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
		if (eap_ikev2_process_fragment(data, flags, message_length,
					       pos, end - pos) < 0)
			eap_ikev2_state(data, FAIL);
		else
			eap_ikev2_state(data, FRAG_ACK);
		return;
	} else if (data->state == FRAG_ACK) {
		wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
		data->state = MSG;
	}

	if (data->in_buf == NULL) {
		/* Wrap unfragmented messages as wpabuf without extra copy */
		wpabuf_set(&tmpbuf, pos, end - pos);
		data->in_buf = &tmpbuf;
	}

	if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
		if (data->in_buf == &tmpbuf)
			data->in_buf = NULL;
		eap_ikev2_state(data, FAIL);
		return;
	}

	switch (data->ikev2.state) {
	case SA_AUTH:
		/* SA_INIT was sent out, so message have to be
		 * integrity protected from now on. */
		data->keys_ready = 1;
		break;
	case IKEV2_DONE:
		if (data->state == FAIL)
			break;
		wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
			   "successfully");
		if (eap_ikev2_server_keymat(data))
			break;
		eap_ikev2_state(data, DONE);
		break;
	default:
		break;
	}

	if (data->in_buf != &tmpbuf)
		wpabuf_free(data->in_buf);
	data->in_buf = NULL;
}


static Boolean eap_ikev2_isDone(struct eap_sm *sm, void *priv)
{
	struct eap_ikev2_data *data = priv;
	return data->state == DONE || data->state == FAIL;
}


static Boolean eap_ikev2_isSuccess(struct eap_sm *sm, void *priv)
{
	struct eap_ikev2_data *data = priv;
	return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
		data->keymat_ok;
}


static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
{
	struct eap_ikev2_data *data = priv;
	u8 *key;

	if (data->state != DONE || !data->keymat_ok)
		return NULL;

	key = os_malloc(EAP_MSK_LEN);
	if (key) {
		os_memcpy(key, data->keymat, EAP_MSK_LEN);
		*len = EAP_MSK_LEN;
	}

	return key;
}


static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
{
	struct eap_ikev2_data *data = priv;
	u8 *key;

	if (data->state != DONE || !data->keymat_ok)
		return NULL;

	key = os_malloc(EAP_EMSK_LEN);
	if (key) {
		os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
		*len = EAP_EMSK_LEN;
	}

	return key;
}


int eap_server_ikev2_register(void)
{
	struct eap_method *eap;
	int ret;

	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
				      EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
				      "IKEV2");
	if (eap == NULL)
		return -1;

	eap->init = eap_ikev2_init;
	eap->reset = eap_ikev2_reset;
	eap->buildReq = eap_ikev2_buildReq;
	eap->check = eap_ikev2_check;
	eap->process = eap_ikev2_process;
	eap->isDone = eap_ikev2_isDone;
	eap->getKey = eap_ikev2_getKey;
	eap->isSuccess = eap_ikev2_isSuccess;
	eap->get_emsk = eap_ikev2_get_emsk;

	ret = eap_server_method_register(eap);
	if (ret)
		eap_server_method_free(eap);
	return ret;
}
Commit	Line	Data
	1	/*
	2	* EAP-IKEv2 server (RFC 5106)
	3	* Copyright (c) 2007, Jouni Malinen <j@w1.fi>
	4	*
	5	* This software may be distributed under the terms of the BSD license.
	6	* See README for more details.
	7	*/
	8
	9	#include "includes.h"
	10
	11	#include "common.h"
	12	#include "eap_i.h"
	13	#include "eap_common/eap_ikev2_common.h"
	14	#include "ikev2.h"
	15
	16
	17	struct eap_ikev2_data {
	18	struct ikev2_initiator_data ikev2;
	19	enum { MSG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
	20	struct wpabuf *in_buf;
	21	struct wpabuf *out_buf;
	22	size_t out_used;
	23	size_t fragment_size;
	24	int keys_ready;
	25	u8 keymat[EAP_MSK_LEN + EAP_EMSK_LEN];
	26	int keymat_ok;
	27	};
	28
	29
	30	static const u8 * eap_ikev2_get_shared_secret(void ctx, const u8 IDr,
	31	size_t IDr_len,
	32	size_t *secret_len)
	33	{
	34	struct eap_sm *sm = ctx;
	35
	36	if (IDr == NULL) {
	37	wpa_printf(MSG_DEBUG, "EAP-IKEV2: No IDr received - default "
	38	"to user identity from EAP-Identity");
	39	IDr = sm->identity;
	40	IDr_len = sm->identity_len;
	41	}
	42
	43	if (eap_user_get(sm, IDr, IDr_len, 0) < 0 \|\| sm->user == NULL \|\|
	44	sm->user->password == NULL) {
	45	wpa_printf(MSG_DEBUG, "EAP-IKEV2: No user entry found");
	46	return NULL;
	47	}
	48
	49	*secret_len = sm->user->password_len;
	50	return sm->user->password;
	51	}
	52
	53
	54	static const char * eap_ikev2_state_txt(int state)
	55	{
	56	switch (state) {
	57	case MSG:
	58	return "MSG";
	59	case FRAG_ACK:
	60	return "FRAG_ACK";
	61	case WAIT_FRAG_ACK:
	62	return "WAIT_FRAG_ACK";
	63	case DONE:
	64	return "DONE";
	65	case FAIL:
	66	return "FAIL";
	67	default:
	68	return "?";
	69	}
	70	}
	71
	72
	73	static void eap_ikev2_state(struct eap_ikev2_data *data, int state)
	74	{
	75	wpa_printf(MSG_DEBUG, "EAP-IKEV2: %s -> %s",
	76	eap_ikev2_state_txt(data->state),
	77	eap_ikev2_state_txt(state));
	78	data->state = state;
	79	}
	80
	81
	82	static void * eap_ikev2_init(struct eap_sm *sm)
	83	{
	84	struct eap_ikev2_data *data;
	85
	86	data = os_zalloc(sizeof(*data));
	87	if (data == NULL)
	88	return NULL;
	89	data->state = MSG;
	90	data->fragment_size = sm->fragment_size > 0 ? sm->fragment_size :
	91	IKEV2_FRAGMENT_SIZE;
	92	data->ikev2.state = SA_INIT;
	93	data->ikev2.peer_auth = PEER_AUTH_SECRET;
	94	data->ikev2.key_pad = (u8 *) os_strdup("Key Pad for EAP-IKEv2");
	95	if (data->ikev2.key_pad == NULL)
	96	goto failed;
	97	data->ikev2.key_pad_len = 21;
	98
	99	/* TODO: make proposals configurable */
	100	data->ikev2.proposal.proposal_num = 1;
	101	data->ikev2.proposal.integ = AUTH_HMAC_SHA1_96;
	102	data->ikev2.proposal.prf = PRF_HMAC_SHA1;
	103	data->ikev2.proposal.encr = ENCR_AES_CBC;
	104	data->ikev2.proposal.dh = DH_GROUP2_1024BIT_MODP;
	105
	106	data->ikev2.IDi = os_malloc(sm->server_id_len);
	107	if (data->ikev2.IDi == NULL)
	108	goto failed;
	109	os_memcpy(data->ikev2.IDi, sm->server_id, sm->server_id_len);
	110	data->ikev2.IDi_len = sm->server_id_len;
	111
	112	data->ikev2.get_shared_secret = eap_ikev2_get_shared_secret;
	113	data->ikev2.cb_ctx = sm;
	114
	115	return data;
	116
	117	failed:
	118	ikev2_initiator_deinit(&data->ikev2);
	119	os_free(data);
	120	return NULL;
	121	}
	122
	123
	124	static void eap_ikev2_reset(struct eap_sm sm, void priv)
	125	{
	126	struct eap_ikev2_data *data = priv;
	127	wpabuf_free(data->in_buf);
	128	wpabuf_free(data->out_buf);
	129	ikev2_initiator_deinit(&data->ikev2);
	130	os_free(data);
	131	}
	132
	133
	134	static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data, u8 id)
	135	{
	136	struct wpabuf *req;
	137	u8 flags;
	138	size_t send_len, plen, icv_len = 0;
	139
	140	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Request");
	141
	142	flags = 0;
	143	send_len = wpabuf_len(data->out_buf) - data->out_used;
	144	if (1 + send_len > data->fragment_size) {
	145	send_len = data->fragment_size - 1;
	146	flags \|= IKEV2_FLAGS_MORE_FRAGMENTS;
	147	if (data->out_used == 0) {
	148	flags \|= IKEV2_FLAGS_LENGTH_INCLUDED;
	149	send_len -= 4;
	150	}
	151	}
	152
	153	plen = 1 + send_len;
	154	if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
	155	plen += 4;
	156	if (data->keys_ready) {
	157	const struct ikev2_integ_alg *integ;
	158	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
	159	"Data");
	160	flags \|= IKEV2_FLAGS_ICV_INCLUDED;
	161	integ = ikev2_get_integ(data->ikev2.proposal.integ);
	162	if (integ == NULL) {
	163	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
	164	"transform / cannot generate ICV");
	165	return NULL;
	166	}
	167	icv_len = integ->hash_len;
	168
	169	plen += icv_len;
	170	}
	171	req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
	172	EAP_CODE_REQUEST, id);
	173	if (req == NULL)
	174	return NULL;
	175
	176	wpabuf_put_u8(req, flags); /* Flags */
	177	if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
	178	wpabuf_put_be32(req, wpabuf_len(data->out_buf));
	179
	180	wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
	181	send_len);
	182	data->out_used += send_len;
	183
	184	if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
	185	const u8 *msg = wpabuf_head(req);
	186	size_t len = wpabuf_len(req);
	187	ikev2_integ_hash(data->ikev2.proposal.integ,
	188	data->ikev2.keys.SK_ai,
	189	data->ikev2.keys.SK_integ_len,
	190	msg, len, wpabuf_put(req, icv_len));
	191	}
	192
	193	if (data->out_used == wpabuf_len(data->out_buf)) {
	194	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
	195	"(message sent completely)",
	196	(unsigned long) send_len);
	197	wpabuf_free(data->out_buf);
	198	data->out_buf = NULL;
	199	data->out_used = 0;
	200	} else {
	201	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
	202	"(%lu more to send)", (unsigned long) send_len,
	203	(unsigned long) wpabuf_len(data->out_buf) -
	204	data->out_used);
	205	eap_ikev2_state(data, WAIT_FRAG_ACK);
	206	}
	207
	208	return req;
	209	}
	210
	211
	212	static struct wpabuf * eap_ikev2_buildReq(struct eap_sm sm, void priv, u8 id)
	213	{
	214	struct eap_ikev2_data *data = priv;
	215
	216	switch (data->state) {
	217	case MSG:
	218	if (data->out_buf == NULL) {
	219	data->out_buf = ikev2_initiator_build(&data->ikev2);
	220	if (data->out_buf == NULL) {
	221	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to "
	222	"generate IKEv2 message");
	223	return NULL;
	224	}
	225	data->out_used = 0;
	226	}
	227	/* pass through */
	228	case WAIT_FRAG_ACK:
	229	return eap_ikev2_build_msg(data, id);
	230	case FRAG_ACK:
	231	return eap_ikev2_build_frag_ack(id, EAP_CODE_REQUEST);
	232	default:
	233	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected state %d in "
	234	"buildReq", data->state);
	235	return NULL;
	236	}
	237	}
	238
	239
	240	static Boolean eap_ikev2_check(struct eap_sm sm, void priv,
	241	struct wpabuf *respData)
	242	{
	243	const u8 *pos;
	244	size_t len;
	245
	246	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
	247	&len);
	248	if (pos == NULL) {
	249	wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid frame");
	250	return TRUE;
	251	}
	252
	253	return FALSE;
	254	}
	255
	256
	257	static int eap_ikev2_process_icv(struct eap_ikev2_data *data,
	258	const struct wpabuf *respData,
	259	u8 flags, const u8 pos, const u8 *end)
	260	{
	261	if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
	262	int icv_len = eap_ikev2_validate_icv(
	263	data->ikev2.proposal.integ, &data->ikev2.keys, 0,
	264	respData, pos, *end);
	265	if (icv_len < 0)
	266	return -1;
	267	/* Hide Integrity Checksum Data from further processing */
	268	*end -= icv_len;
	269	} else if (data->keys_ready) {
	270	wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
	271	"included integrity checksum");
	272	return -1;
	273	}
	274
	275	return 0;
	276	}
	277
	278
	279	static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
	280	const u8 *buf, size_t len)
	281	{
	282	/* Process continuation of a pending message */
	283	if (len > wpabuf_tailroom(data->in_buf)) {
	284	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
	285	eap_ikev2_state(data, FAIL);
	286	return -1;
	287	}
	288
	289	wpabuf_put_data(data->in_buf, buf, len);
	290	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting for %lu "
	291	"bytes more", (unsigned long) len,
	292	(unsigned long) wpabuf_tailroom(data->in_buf));
	293
	294	return 0;
	295	}
	296
	297
	298	static int eap_ikev2_process_fragment(struct eap_ikev2_data *data,
	299	u8 flags, u32 message_length,
	300	const u8 *buf, size_t len)
	301	{
	302	/* Process a fragment that is not the last one of the message */
	303	if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
	304	wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
	305	"a fragmented packet");
	306	return -1;
	307	}
	308
	309	if (data->in_buf == NULL) {
	310	/* First fragment of the message */
	311	data->in_buf = wpabuf_alloc(message_length);
	312	if (data->in_buf == NULL) {
	313	wpa_printf(MSG_DEBUG, "EAP-IKEV2: No memory for "
	314	"message");
	315	return -1;
	316	}
	317	wpabuf_put_data(data->in_buf, buf, len);
	318	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes in first "
	319	"fragment, waiting for %lu bytes more",
	320	(unsigned long) len,
	321	(unsigned long) wpabuf_tailroom(data->in_buf));
	322	}
	323
	324	return 0;
	325	}
	326
	327
	328	static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
	329	{
	330	if (eap_ikev2_derive_keymat(
	331	data->ikev2.proposal.prf, &data->ikev2.keys,
	332	data->ikev2.i_nonce, data->ikev2.i_nonce_len,
	333	data->ikev2.r_nonce, data->ikev2.r_nonce_len,
	334	data->keymat) < 0) {
	335	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
	336	"key material");
	337	return -1;
	338	}
	339	data->keymat_ok = 1;
	340	return 0;
	341	}
	342
	343
	344	static void eap_ikev2_process(struct eap_sm sm, void priv,
	345	struct wpabuf *respData)
	346	{
	347	struct eap_ikev2_data *data = priv;
	348	const u8 start, pos, *end;
	349	size_t len;
	350	u8 flags;
	351	u32 message_length = 0;
	352	struct wpabuf tmpbuf;
	353
	354	pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
	355	&len);
	356	if (pos == NULL)
	357	return; /* Should not happen; message already verified */
	358
	359	start = pos;
	360	end = start + len;
	361
	362	if (len == 0) {
	363	/* fragment ack */
	364	flags = 0;
	365	} else
	366	flags = *pos++;
	367
	368	if (eap_ikev2_process_icv(data, respData, flags, pos, &end) < 0) {
	369	eap_ikev2_state(data, FAIL);
	370	return;
	371	}
	372
	373	if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
	374	if (end - pos < 4) {
	375	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
	376	eap_ikev2_state(data, FAIL);
	377	return;
	378	}
	379	message_length = WPA_GET_BE32(pos);
	380	pos += 4;
	381
	382	if (message_length < (u32) (end - pos)) {
	383	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
	384	"Length (%d; %ld remaining in this msg)",
	385	message_length, (long) (end - pos));
	386	eap_ikev2_state(data, FAIL);
	387	return;
	388	}
	389	}
	390	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
	391	"Message Length %u", flags, message_length);
	392
	393	if (data->state == WAIT_FRAG_ACK) {
	394	if (len != 0) {
	395	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
	396	"in WAIT_FRAG_ACK state");
	397	eap_ikev2_state(data, FAIL);
	398	return;
	399	}
	400	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
	401	eap_ikev2_state(data, MSG);
	402	return;
	403	}
	404
	405	if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
	406	eap_ikev2_state(data, FAIL);
	407	return;
	408	}
	409
	410	if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
	411	if (eap_ikev2_process_fragment(data, flags, message_length,
	412	pos, end - pos) < 0)
	413	eap_ikev2_state(data, FAIL);
	414	else
	415	eap_ikev2_state(data, FRAG_ACK);
	416	return;
	417	} else if (data->state == FRAG_ACK) {
	418	wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
	419	data->state = MSG;
	420	}
	421
	422	if (data->in_buf == NULL) {
	423	/* Wrap unfragmented messages as wpabuf without extra copy */
	424	wpabuf_set(&tmpbuf, pos, end - pos);
	425	data->in_buf = &tmpbuf;
	426	}
	427
	428	if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
	429	if (data->in_buf == &tmpbuf)
	430	data->in_buf = NULL;
	431	eap_ikev2_state(data, FAIL);
	432	return;
	433	}
	434
	435	switch (data->ikev2.state) {
	436	case SA_AUTH:
	437	/* SA_INIT was sent out, so message have to be
	438	* integrity protected from now on. */
	439	data->keys_ready = 1;
	440	break;
	441	case IKEV2_DONE:
	442	if (data->state == FAIL)
	443	break;
	444	wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
	445	"successfully");
	446	if (eap_ikev2_server_keymat(data))
	447	break;
	448	eap_ikev2_state(data, DONE);
	449	break;
	450	default:
	451	break;
	452	}
	453
	454	if (data->in_buf != &tmpbuf)
	455	wpabuf_free(data->in_buf);
	456	data->in_buf = NULL;
	457	}
	458
	459
	460	static Boolean eap_ikev2_isDone(struct eap_sm sm, void priv)
	461	{
	462	struct eap_ikev2_data *data = priv;
	463	return data->state == DONE \|\| data->state == FAIL;
	464	}
	465
	466
	467	static Boolean eap_ikev2_isSuccess(struct eap_sm sm, void priv)
	468	{
	469	struct eap_ikev2_data *data = priv;
	470	return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
	471	data->keymat_ok;
	472	}
	473
	474
	475	static u8 * eap_ikev2_getKey(struct eap_sm sm, void priv, size_t *len)
	476	{
	477	struct eap_ikev2_data *data = priv;
	478	u8 *key;
	479
	480	if (data->state != DONE \|\| !data->keymat_ok)
	481	return NULL;
	482
	483	key = os_malloc(EAP_MSK_LEN);
	484	if (key) {
	485	os_memcpy(key, data->keymat, EAP_MSK_LEN);
	486	*len = EAP_MSK_LEN;
	487	}
	488
	489	return key;
	490	}
	491
	492
	493	static u8 * eap_ikev2_get_emsk(struct eap_sm sm, void priv, size_t *len)
	494	{
	495	struct eap_ikev2_data *data = priv;
	496	u8 *key;
	497
	498	if (data->state != DONE \|\| !data->keymat_ok)
	499	return NULL;
	500
	501	key = os_malloc(EAP_EMSK_LEN);
	502	if (key) {
	503	os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
	504	*len = EAP_EMSK_LEN;
	505	}
	506
	507	return key;
	508	}
	509
	510
	511	int eap_server_ikev2_register(void)
	512	{
	513	struct eap_method *eap;
	514	int ret;
	515
	516	eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
	517	EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
	518	"IKEV2");
	519	if (eap == NULL)
	520	return -1;
	521
	522	eap->init = eap_ikev2_init;
	523	eap->reset = eap_ikev2_reset;
	524	eap->buildReq = eap_ikev2_buildReq;
	525	eap->check = eap_ikev2_check;
	526	eap->process = eap_ikev2_process;
	527	eap->isDone = eap_ikev2_isDone;
	528	eap->getKey = eap_ikev2_getKey;
	529	eap->isSuccess = eap_ikev2_isSuccess;
	530	eap->get_emsk = eap_ikev2_get_emsk;
	531
	532	ret = eap_server_method_register(eap);
	533	if (ret)
	534	eap_server_method_free(eap);
	535	return ret;
	536	}