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 = IKEV2_FRAGMENT_SIZE;
97 data->ikev2.state = SA_INIT;
98 data->ikev2.peer_auth = PEER_AUTH_SECRET;
99 data->ikev2.key_pad = (u8 *) os_strdup("Key Pad for EAP-IKEv2");
100 if (data->ikev2.key_pad == NULL)
102 data->ikev2.key_pad_len = 21;
104 /* TODO: make proposals configurable */
105 data->ikev2.proposal.proposal_num = 1;
106 data->ikev2.proposal.integ = AUTH_HMAC_SHA1_96;
107 data->ikev2.proposal.prf = PRF_HMAC_SHA1;
108 data->ikev2.proposal.encr = ENCR_AES_CBC;
109 data->ikev2.proposal.dh = DH_GROUP2_1024BIT_MODP;
111 data->ikev2.IDi = (u8 *) os_strdup("hostapd");
112 data->ikev2.IDi_len = 7;
114 data->ikev2.get_shared_secret = eap_ikev2_get_shared_secret;
115 data->ikev2.cb_ctx = sm;
120 ikev2_initiator_deinit(&data->ikev2);
126 static void eap_ikev2_reset(struct eap_sm *sm, void *priv)
128 struct eap_ikev2_data *data = priv;
129 wpabuf_free(data->in_buf);
130 wpabuf_free(data->out_buf);
131 ikev2_initiator_deinit(&data->ikev2);
136 static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data, u8 id)
140 size_t send_len, plen, icv_len = 0;
142 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Request");
145 send_len = wpabuf_len(data->out_buf) - data->out_used;
146 if (1 + send_len > data->fragment_size) {
147 send_len = data->fragment_size - 1;
148 flags |= IKEV2_FLAGS_MORE_FRAGMENTS;
149 if (data->out_used == 0) {
150 flags |= IKEV2_FLAGS_LENGTH_INCLUDED;
156 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
158 if (data->keys_ready) {
159 const struct ikev2_integ_alg *integ;
160 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
162 flags |= IKEV2_FLAGS_ICV_INCLUDED;
163 integ = ikev2_get_integ(data->ikev2.proposal.integ);
165 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
166 "transform / cannot generate ICV");
169 icv_len = integ->hash_len;
173 req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
174 EAP_CODE_REQUEST, id);
178 wpabuf_put_u8(req, flags); /* Flags */
179 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
180 wpabuf_put_be32(req, wpabuf_len(data->out_buf));
182 wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
184 data->out_used += send_len;
186 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
187 const u8 *msg = wpabuf_head(req);
188 size_t len = wpabuf_len(req);
189 ikev2_integ_hash(data->ikev2.proposal.integ,
190 data->ikev2.keys.SK_ai,
191 data->ikev2.keys.SK_integ_len,
192 msg, len, wpabuf_put(req, icv_len));
195 if (data->out_used == wpabuf_len(data->out_buf)) {
196 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
197 "(message sent completely)",
198 (unsigned long) send_len);
199 wpabuf_free(data->out_buf);
200 data->out_buf = NULL;
203 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
204 "(%lu more to send)", (unsigned long) send_len,
205 (unsigned long) wpabuf_len(data->out_buf) -
207 eap_ikev2_state(data, WAIT_FRAG_ACK);
214 static struct wpabuf * eap_ikev2_buildReq(struct eap_sm *sm, void *priv, u8 id)
216 struct eap_ikev2_data *data = priv;
218 switch (data->state) {
220 if (data->out_buf == NULL) {
221 data->out_buf = ikev2_initiator_build(&data->ikev2);
222 if (data->out_buf == NULL) {
223 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to "
224 "generate IKEv2 message");
231 return eap_ikev2_build_msg(data, id);
233 return eap_ikev2_build_frag_ack(id, EAP_CODE_REQUEST);
235 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected state %d in "
236 "buildReq", data->state);
242 static Boolean eap_ikev2_check(struct eap_sm *sm, void *priv,
243 struct wpabuf *respData)
248 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
251 wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid frame");
259 static int eap_ikev2_process_icv(struct eap_ikev2_data *data,
260 const struct wpabuf *respData,
261 u8 flags, const u8 *pos, const u8 **end)
263 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
264 int icv_len = eap_ikev2_validate_icv(
265 data->ikev2.proposal.integ, &data->ikev2.keys, 0,
266 respData, pos, *end);
269 /* Hide Integrity Checksum Data from further processing */
271 } else if (data->keys_ready) {
272 wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
273 "included integrity checksum");
281 static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
282 const u8 *buf, size_t len)
284 /* Process continuation of a pending message */
285 if (len > wpabuf_tailroom(data->in_buf)) {
286 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
287 eap_ikev2_state(data, FAIL);
291 wpabuf_put_data(data->in_buf, buf, len);
292 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting for %lu "
293 "bytes more", (unsigned long) len,
294 (unsigned long) wpabuf_tailroom(data->in_buf));
300 static int eap_ikev2_process_fragment(struct eap_ikev2_data *data,
301 u8 flags, u32 message_length,
302 const u8 *buf, size_t len)
304 /* Process a fragment that is not the last one of the message */
305 if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
306 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
307 "a fragmented packet");
311 if (data->in_buf == NULL) {
312 /* First fragment of the message */
313 data->in_buf = wpabuf_alloc(message_length);
314 if (data->in_buf == NULL) {
315 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No memory for "
319 wpabuf_put_data(data->in_buf, buf, len);
320 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes in first "
321 "fragment, waiting for %lu bytes more",
323 (unsigned long) wpabuf_tailroom(data->in_buf));
330 static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
332 if (eap_ikev2_derive_keymat(
333 data->ikev2.proposal.prf, &data->ikev2.keys,
334 data->ikev2.i_nonce, data->ikev2.i_nonce_len,
335 data->ikev2.r_nonce, data->ikev2.r_nonce_len,
337 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
346 static void eap_ikev2_process(struct eap_sm *sm, void *priv,
347 struct wpabuf *respData)
349 struct eap_ikev2_data *data = priv;
350 const u8 *start, *pos, *end;
353 u32 message_length = 0;
354 struct wpabuf tmpbuf;
356 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
359 return; /* Should not happen; message already verified */
370 if (eap_ikev2_process_icv(data, respData, flags, pos, &end) < 0) {
371 eap_ikev2_state(data, FAIL);
375 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
377 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
378 eap_ikev2_state(data, FAIL);
381 message_length = WPA_GET_BE32(pos);
384 if (message_length < (u32) (end - pos)) {
385 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
386 "Length (%d; %ld remaining in this msg)",
387 message_length, (long) (end - pos));
388 eap_ikev2_state(data, FAIL);
392 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
393 "Message Length %u", flags, message_length);
395 if (data->state == WAIT_FRAG_ACK) {
397 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
398 "in WAIT_FRAG_ACK state");
399 eap_ikev2_state(data, FAIL);
402 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
403 eap_ikev2_state(data, MSG);
407 if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
408 eap_ikev2_state(data, FAIL);
412 if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
413 if (eap_ikev2_process_fragment(data, flags, message_length,
415 eap_ikev2_state(data, FAIL);
417 eap_ikev2_state(data, FRAG_ACK);
419 } else if (data->state == FRAG_ACK) {
420 wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
424 if (data->in_buf == NULL) {
425 /* Wrap unfragmented messages as wpabuf without extra copy */
426 wpabuf_set(&tmpbuf, pos, end - pos);
427 data->in_buf = &tmpbuf;
430 if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
431 if (data->in_buf == &tmpbuf)
433 eap_ikev2_state(data, FAIL);
437 switch (data->ikev2.state) {
439 /* SA_INIT was sent out, so message have to be
440 * integrity protected from now on. */
441 data->keys_ready = 1;
444 if (data->state == FAIL)
446 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
448 if (eap_ikev2_server_keymat(data))
450 eap_ikev2_state(data, DONE);
456 if (data->in_buf != &tmpbuf)
457 wpabuf_free(data->in_buf);
462 static Boolean eap_ikev2_isDone(struct eap_sm *sm, void *priv)
464 struct eap_ikev2_data *data = priv;
465 return data->state == DONE || data->state == FAIL;
469 static Boolean eap_ikev2_isSuccess(struct eap_sm *sm, void *priv)
471 struct eap_ikev2_data *data = priv;
472 return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
477 static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
479 struct eap_ikev2_data *data = priv;
482 if (data->state != DONE || !data->keymat_ok)
485 key = os_malloc(EAP_MSK_LEN);
487 os_memcpy(key, data->keymat, EAP_MSK_LEN);
495 static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
497 struct eap_ikev2_data *data = priv;
500 if (data->state != DONE || !data->keymat_ok)
503 key = os_malloc(EAP_EMSK_LEN);
505 os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
513 int eap_server_ikev2_register(void)
515 struct eap_method *eap;
518 eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
519 EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
524 eap->init = eap_ikev2_init;
525 eap->reset = eap_ikev2_reset;
526 eap->buildReq = eap_ikev2_buildReq;
527 eap->check = eap_ikev2_check;
528 eap->process = eap_ikev2_process;
529 eap->isDone = eap_ikev2_isDone;
530 eap->getKey = eap_ikev2_getKey;
531 eap->isSuccess = eap_ikev2_isSuccess;
532 eap->get_emsk = eap_ikev2_get_emsk;
534 ret = eap_server_method_register(eap);
536 eap_server_method_free(eap);