2 * EAP-IKEv2 server (RFC 5106)
3 * Copyright (c) 2007, Jouni Malinen <j@w1.fi>
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
13 #include "eap_common/eap_ikev2_common.h"
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;
25 u8 keymat[EAP_MSK_LEN + EAP_EMSK_LEN];
30 static const u8 * eap_ikev2_get_shared_secret(void *ctx, const u8 *IDr,
34 struct eap_sm *sm = ctx;
37 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No IDr received - default "
38 "to user identity from EAP-Identity");
40 IDr_len = sm->identity_len;
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");
49 *secret_len = sm->user->password_len;
50 return sm->user->password;
54 static const char * eap_ikev2_state_txt(int state)
62 return "WAIT_FRAG_ACK";
73 static void eap_ikev2_state(struct eap_ikev2_data *data, int state)
75 wpa_printf(MSG_DEBUG, "EAP-IKEV2: %s -> %s",
76 eap_ikev2_state_txt(data->state),
77 eap_ikev2_state_txt(state));
82 static void * eap_ikev2_init(struct eap_sm *sm)
84 struct eap_ikev2_data *data;
86 data = os_zalloc(sizeof(*data));
90 data->fragment_size = sm->fragment_size > 0 ? sm->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)
97 data->ikev2.key_pad_len = 21;
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;
106 data->ikev2.IDi = os_malloc(sm->server_id_len);
107 if (data->ikev2.IDi == NULL)
109 os_memcpy(data->ikev2.IDi, sm->server_id, sm->server_id_len);
110 data->ikev2.IDi_len = sm->server_id_len;
112 data->ikev2.get_shared_secret = eap_ikev2_get_shared_secret;
113 data->ikev2.cb_ctx = sm;
118 ikev2_initiator_deinit(&data->ikev2);
124 static void eap_ikev2_reset(struct eap_sm *sm, void *priv)
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 bin_clear_free(data, sizeof(*data));
134 static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data, u8 id)
138 size_t send_len, plen, icv_len = 0;
140 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Request");
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;
154 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
156 if (data->keys_ready) {
157 const struct ikev2_integ_alg *integ;
158 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
160 flags |= IKEV2_FLAGS_ICV_INCLUDED;
161 integ = ikev2_get_integ(data->ikev2.proposal.integ);
163 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
164 "transform / cannot generate ICV");
167 icv_len = integ->hash_len;
171 req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
172 EAP_CODE_REQUEST, id);
176 wpabuf_put_u8(req, flags); /* Flags */
177 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
178 wpabuf_put_be32(req, wpabuf_len(data->out_buf));
180 wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
182 data->out_used += send_len;
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));
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;
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) -
205 eap_ikev2_state(data, WAIT_FRAG_ACK);
212 static struct wpabuf * eap_ikev2_buildReq(struct eap_sm *sm, void *priv, u8 id)
214 struct eap_ikev2_data *data = priv;
216 switch (data->state) {
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");
229 return eap_ikev2_build_msg(data, id);
231 return eap_ikev2_build_frag_ack(id, EAP_CODE_REQUEST);
233 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected state %d in "
234 "buildReq", data->state);
240 static Boolean eap_ikev2_check(struct eap_sm *sm, void *priv,
241 struct wpabuf *respData)
246 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
249 wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid frame");
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,
262 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
263 int icv_len = eap_ikev2_validate_icv(
264 data->ikev2.proposal.integ, &data->ikev2.keys, 0,
265 respData, pos, *end);
268 /* Hide Integrity Checksum Data from further processing */
270 } else if (data->keys_ready && !frag_ack) {
271 wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
272 "included integrity checksum");
280 static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
281 const u8 *buf, size_t len)
283 /* Process continuation of a pending message */
284 if (len > wpabuf_tailroom(data->in_buf)) {
285 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
286 eap_ikev2_state(data, FAIL);
290 wpabuf_put_data(data->in_buf, buf, len);
291 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting for %lu "
292 "bytes more", (unsigned long) len,
293 (unsigned long) wpabuf_tailroom(data->in_buf));
299 static int eap_ikev2_process_fragment(struct eap_ikev2_data *data,
300 u8 flags, u32 message_length,
301 const u8 *buf, size_t len)
303 /* Process a fragment that is not the last one of the message */
304 if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
305 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
306 "a fragmented packet");
310 if (data->in_buf == NULL) {
311 /* First fragment of the message */
312 if (message_length > 50000) {
313 /* Limit maximum memory allocation */
314 wpa_printf(MSG_DEBUG,
315 "EAP-IKEV2: Ignore too long message");
318 data->in_buf = wpabuf_alloc(message_length);
319 if (data->in_buf == NULL) {
320 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No memory for "
324 wpabuf_put_data(data->in_buf, buf, len);
325 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes in first "
326 "fragment, waiting for %lu bytes more",
328 (unsigned long) wpabuf_tailroom(data->in_buf));
335 static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
337 if (eap_ikev2_derive_keymat(
338 data->ikev2.proposal.prf, &data->ikev2.keys,
339 data->ikev2.i_nonce, data->ikev2.i_nonce_len,
340 data->ikev2.r_nonce, data->ikev2.r_nonce_len,
342 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
351 static void eap_ikev2_process(struct eap_sm *sm, void *priv,
352 struct wpabuf *respData)
354 struct eap_ikev2_data *data = priv;
355 const u8 *start, *pos, *end;
358 u32 message_length = 0;
359 struct wpabuf tmpbuf;
361 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
364 return; /* Should not happen; message already verified */
375 if (eap_ikev2_process_icv(data, respData, flags, pos, &end,
376 data->state == WAIT_FRAG_ACK && len == 0) < 0)
378 eap_ikev2_state(data, FAIL);
382 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
384 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
385 eap_ikev2_state(data, FAIL);
388 message_length = WPA_GET_BE32(pos);
391 if (message_length < (u32) (end - pos)) {
392 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
393 "Length (%d; %ld remaining in this msg)",
394 message_length, (long) (end - pos));
395 eap_ikev2_state(data, FAIL);
399 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
400 "Message Length %u", flags, message_length);
402 if (data->state == WAIT_FRAG_ACK) {
404 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
405 "in WAIT_FRAG_ACK state");
406 eap_ikev2_state(data, FAIL);
409 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
410 eap_ikev2_state(data, MSG);
414 if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
415 eap_ikev2_state(data, FAIL);
419 if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
420 if (eap_ikev2_process_fragment(data, flags, message_length,
422 eap_ikev2_state(data, FAIL);
424 eap_ikev2_state(data, FRAG_ACK);
426 } else if (data->state == FRAG_ACK) {
427 wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
431 if (data->in_buf == NULL) {
432 /* Wrap unfragmented messages as wpabuf without extra copy */
433 wpabuf_set(&tmpbuf, pos, end - pos);
434 data->in_buf = &tmpbuf;
437 if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
438 if (data->in_buf == &tmpbuf)
440 eap_ikev2_state(data, FAIL);
444 switch (data->ikev2.state) {
446 /* SA_INIT was sent out, so message have to be
447 * integrity protected from now on. */
448 data->keys_ready = 1;
451 if (data->state == FAIL)
453 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
455 if (eap_ikev2_server_keymat(data))
457 eap_ikev2_state(data, DONE);
463 if (data->in_buf != &tmpbuf)
464 wpabuf_free(data->in_buf);
469 static Boolean eap_ikev2_isDone(struct eap_sm *sm, void *priv)
471 struct eap_ikev2_data *data = priv;
472 return data->state == DONE || data->state == FAIL;
476 static Boolean eap_ikev2_isSuccess(struct eap_sm *sm, void *priv)
478 struct eap_ikev2_data *data = priv;
479 return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
484 static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
486 struct eap_ikev2_data *data = priv;
489 if (data->state != DONE || !data->keymat_ok)
492 key = os_malloc(EAP_MSK_LEN);
494 os_memcpy(key, data->keymat, EAP_MSK_LEN);
502 static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
504 struct eap_ikev2_data *data = priv;
507 if (data->state != DONE || !data->keymat_ok)
510 key = os_malloc(EAP_EMSK_LEN);
512 os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
520 static u8 * eap_ikev2_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
522 struct eap_ikev2_data *data = priv;
527 if (data->state != DONE || !data->keymat_ok)
530 sid_len = 1 + data->ikev2.i_nonce_len + data->ikev2.r_nonce_len;
531 sid = os_malloc(sid_len);
534 sid[offset] = EAP_TYPE_IKEV2;
536 os_memcpy(sid + offset, data->ikev2.i_nonce,
537 data->ikev2.i_nonce_len);
538 offset += data->ikev2.i_nonce_len;
539 os_memcpy(sid + offset, data->ikev2.r_nonce,
540 data->ikev2.r_nonce_len);
542 wpa_hexdump(MSG_DEBUG, "EAP-IKEV2: Derived Session-Id",
550 int eap_server_ikev2_register(void)
552 struct eap_method *eap;
555 eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
556 EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
561 eap->init = eap_ikev2_init;
562 eap->reset = eap_ikev2_reset;
563 eap->buildReq = eap_ikev2_buildReq;
564 eap->check = eap_ikev2_check;
565 eap->process = eap_ikev2_process;
566 eap->isDone = eap_ikev2_isDone;
567 eap->getKey = eap_ikev2_getKey;
568 eap->isSuccess = eap_ikev2_isSuccess;
569 eap->get_emsk = eap_ikev2_get_emsk;
570 eap->getSessionId = eap_ikev2_get_session_id;
572 ret = eap_server_method_register(eap);
574 eap_server_method_free(eap);