2 * EAP-IKEv2 server (RFC 5106)
3 * Copyright (c) 2007, Jouni Malinen <j@w1.fi>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * Alternatively, this software may be distributed under the terms of BSD
12 * See README and COPYING for more details.
19 #include "eap_common/eap_ikev2_common.h"
23 struct eap_ikev2_data {
24 struct ikev2_initiator_data ikev2;
25 enum { MSG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
26 struct wpabuf *in_buf;
27 struct wpabuf *out_buf;
31 u8 keymat[EAP_MSK_LEN + EAP_EMSK_LEN];
36 static const u8 * eap_ikev2_get_shared_secret(void *ctx, const u8 *IDr,
40 struct eap_sm *sm = ctx;
43 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No IDr received - default "
44 "to user identity from EAP-Identity");
46 IDr_len = sm->identity_len;
49 if (eap_user_get(sm, IDr, IDr_len, 0) < 0 || sm->user == NULL ||
50 sm->user->password == NULL) {
51 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No user entry found");
55 *secret_len = sm->user->password_len;
56 return sm->user->password;
60 static const char * eap_ikev2_state_txt(int state)
68 return "WAIT_FRAG_ACK";
79 static void eap_ikev2_state(struct eap_ikev2_data *data, int state)
81 wpa_printf(MSG_DEBUG, "EAP-IKEV2: %s -> %s",
82 eap_ikev2_state_txt(data->state),
83 eap_ikev2_state_txt(state));
88 static void * eap_ikev2_init(struct eap_sm *sm)
90 struct eap_ikev2_data *data;
92 data = os_zalloc(sizeof(*data));
96 data->fragment_size = sm->fragment_size > 0 ? sm->fragment_size :
98 data->ikev2.state = SA_INIT;
99 data->ikev2.peer_auth = PEER_AUTH_SECRET;
100 data->ikev2.key_pad = (u8 *) os_strdup("Key Pad for EAP-IKEv2");
101 if (data->ikev2.key_pad == NULL)
103 data->ikev2.key_pad_len = 21;
105 /* TODO: make proposals configurable */
106 data->ikev2.proposal.proposal_num = 1;
107 data->ikev2.proposal.integ = AUTH_HMAC_SHA1_96;
108 data->ikev2.proposal.prf = PRF_HMAC_SHA1;
109 data->ikev2.proposal.encr = ENCR_AES_CBC;
110 data->ikev2.proposal.dh = DH_GROUP2_1024BIT_MODP;
112 data->ikev2.IDi = (u8 *) os_strdup("hostapd");
113 data->ikev2.IDi_len = 7;
115 data->ikev2.get_shared_secret = eap_ikev2_get_shared_secret;
116 data->ikev2.cb_ctx = sm;
121 ikev2_initiator_deinit(&data->ikev2);
127 static void eap_ikev2_reset(struct eap_sm *sm, void *priv)
129 struct eap_ikev2_data *data = priv;
130 wpabuf_free(data->in_buf);
131 wpabuf_free(data->out_buf);
132 ikev2_initiator_deinit(&data->ikev2);
137 static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data, u8 id)
141 size_t send_len, plen, icv_len = 0;
143 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Request");
146 send_len = wpabuf_len(data->out_buf) - data->out_used;
147 if (1 + send_len > data->fragment_size) {
148 send_len = data->fragment_size - 1;
149 flags |= IKEV2_FLAGS_MORE_FRAGMENTS;
150 if (data->out_used == 0) {
151 flags |= IKEV2_FLAGS_LENGTH_INCLUDED;
157 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
159 if (data->keys_ready) {
160 const struct ikev2_integ_alg *integ;
161 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
163 flags |= IKEV2_FLAGS_ICV_INCLUDED;
164 integ = ikev2_get_integ(data->ikev2.proposal.integ);
166 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
167 "transform / cannot generate ICV");
170 icv_len = integ->hash_len;
174 req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
175 EAP_CODE_REQUEST, id);
179 wpabuf_put_u8(req, flags); /* Flags */
180 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
181 wpabuf_put_be32(req, wpabuf_len(data->out_buf));
183 wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
185 data->out_used += send_len;
187 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
188 const u8 *msg = wpabuf_head(req);
189 size_t len = wpabuf_len(req);
190 ikev2_integ_hash(data->ikev2.proposal.integ,
191 data->ikev2.keys.SK_ai,
192 data->ikev2.keys.SK_integ_len,
193 msg, len, wpabuf_put(req, icv_len));
196 if (data->out_used == wpabuf_len(data->out_buf)) {
197 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
198 "(message sent completely)",
199 (unsigned long) send_len);
200 wpabuf_free(data->out_buf);
201 data->out_buf = NULL;
204 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
205 "(%lu more to send)", (unsigned long) send_len,
206 (unsigned long) wpabuf_len(data->out_buf) -
208 eap_ikev2_state(data, WAIT_FRAG_ACK);
215 static struct wpabuf * eap_ikev2_buildReq(struct eap_sm *sm, void *priv, u8 id)
217 struct eap_ikev2_data *data = priv;
219 switch (data->state) {
221 if (data->out_buf == NULL) {
222 data->out_buf = ikev2_initiator_build(&data->ikev2);
223 if (data->out_buf == NULL) {
224 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to "
225 "generate IKEv2 message");
232 return eap_ikev2_build_msg(data, id);
234 return eap_ikev2_build_frag_ack(id, EAP_CODE_REQUEST);
236 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected state %d in "
237 "buildReq", data->state);
243 static Boolean eap_ikev2_check(struct eap_sm *sm, void *priv,
244 struct wpabuf *respData)
249 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
252 wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid frame");
260 static int eap_ikev2_process_icv(struct eap_ikev2_data *data,
261 const struct wpabuf *respData,
262 u8 flags, const u8 *pos, const u8 **end)
264 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
265 int icv_len = eap_ikev2_validate_icv(
266 data->ikev2.proposal.integ, &data->ikev2.keys, 0,
267 respData, pos, *end);
270 /* Hide Integrity Checksum Data from further processing */
272 } else if (data->keys_ready) {
273 wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
274 "included integrity checksum");
282 static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
283 const u8 *buf, size_t len)
285 /* Process continuation of a pending message */
286 if (len > wpabuf_tailroom(data->in_buf)) {
287 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
288 eap_ikev2_state(data, FAIL);
292 wpabuf_put_data(data->in_buf, buf, len);
293 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting for %lu "
294 "bytes more", (unsigned long) len,
295 (unsigned long) wpabuf_tailroom(data->in_buf));
301 static int eap_ikev2_process_fragment(struct eap_ikev2_data *data,
302 u8 flags, u32 message_length,
303 const u8 *buf, size_t len)
305 /* Process a fragment that is not the last one of the message */
306 if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
307 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
308 "a fragmented packet");
312 if (data->in_buf == NULL) {
313 /* First fragment of the message */
314 data->in_buf = wpabuf_alloc(message_length);
315 if (data->in_buf == NULL) {
316 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No memory for "
320 wpabuf_put_data(data->in_buf, buf, len);
321 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes in first "
322 "fragment, waiting for %lu bytes more",
324 (unsigned long) wpabuf_tailroom(data->in_buf));
331 static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
333 if (eap_ikev2_derive_keymat(
334 data->ikev2.proposal.prf, &data->ikev2.keys,
335 data->ikev2.i_nonce, data->ikev2.i_nonce_len,
336 data->ikev2.r_nonce, data->ikev2.r_nonce_len,
338 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
347 static void eap_ikev2_process(struct eap_sm *sm, void *priv,
348 struct wpabuf *respData)
350 struct eap_ikev2_data *data = priv;
351 const u8 *start, *pos, *end;
354 u32 message_length = 0;
355 struct wpabuf tmpbuf;
357 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
360 return; /* Should not happen; message already verified */
371 if (eap_ikev2_process_icv(data, respData, flags, pos, &end) < 0) {
372 eap_ikev2_state(data, FAIL);
376 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
378 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
379 eap_ikev2_state(data, FAIL);
382 message_length = WPA_GET_BE32(pos);
385 if (message_length < (u32) (end - pos)) {
386 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
387 "Length (%d; %ld remaining in this msg)",
388 message_length, (long) (end - pos));
389 eap_ikev2_state(data, FAIL);
393 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
394 "Message Length %u", flags, message_length);
396 if (data->state == WAIT_FRAG_ACK) {
398 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
399 "in WAIT_FRAG_ACK state");
400 eap_ikev2_state(data, FAIL);
403 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
404 eap_ikev2_state(data, MSG);
408 if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
409 eap_ikev2_state(data, FAIL);
413 if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
414 if (eap_ikev2_process_fragment(data, flags, message_length,
416 eap_ikev2_state(data, FAIL);
418 eap_ikev2_state(data, FRAG_ACK);
420 } else if (data->state == FRAG_ACK) {
421 wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
425 if (data->in_buf == NULL) {
426 /* Wrap unfragmented messages as wpabuf without extra copy */
427 wpabuf_set(&tmpbuf, pos, end - pos);
428 data->in_buf = &tmpbuf;
431 if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
432 if (data->in_buf == &tmpbuf)
434 eap_ikev2_state(data, FAIL);
438 switch (data->ikev2.state) {
440 /* SA_INIT was sent out, so message have to be
441 * integrity protected from now on. */
442 data->keys_ready = 1;
445 if (data->state == FAIL)
447 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
449 if (eap_ikev2_server_keymat(data))
451 eap_ikev2_state(data, DONE);
457 if (data->in_buf != &tmpbuf)
458 wpabuf_free(data->in_buf);
463 static Boolean eap_ikev2_isDone(struct eap_sm *sm, void *priv)
465 struct eap_ikev2_data *data = priv;
466 return data->state == DONE || data->state == FAIL;
470 static Boolean eap_ikev2_isSuccess(struct eap_sm *sm, void *priv)
472 struct eap_ikev2_data *data = priv;
473 return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
478 static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
480 struct eap_ikev2_data *data = priv;
483 if (data->state != DONE || !data->keymat_ok)
486 key = os_malloc(EAP_MSK_LEN);
488 os_memcpy(key, data->keymat, EAP_MSK_LEN);
496 static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
498 struct eap_ikev2_data *data = priv;
501 if (data->state != DONE || !data->keymat_ok)
504 key = os_malloc(EAP_EMSK_LEN);
506 os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
514 int eap_server_ikev2_register(void)
516 struct eap_method *eap;
519 eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
520 EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
525 eap->init = eap_ikev2_init;
526 eap->reset = eap_ikev2_reset;
527 eap->buildReq = eap_ikev2_buildReq;
528 eap->check = eap_ikev2_check;
529 eap->process = eap_ikev2_process;
530 eap->isDone = eap_ikev2_isDone;
531 eap->getKey = eap_ikev2_getKey;
532 eap->isSuccess = eap_ikev2_isSuccess;
533 eap->get_emsk = eap_ikev2_get_emsk;
535 ret = eap_server_method_register(eap);
537 eap_server_method_free(eap);