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);
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)
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);
267 /* Hide Integrity Checksum Data from further processing */
269 } else if (data->keys_ready) {
270 wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
271 "included integrity checksum");
279 static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
280 const u8 *buf, size_t len)
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);
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));
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)
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");
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 "
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",
321 (unsigned long) wpabuf_tailroom(data->in_buf));
328 static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
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,
335 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
344 static void eap_ikev2_process(struct eap_sm *sm, void *priv,
345 struct wpabuf *respData)
347 struct eap_ikev2_data *data = priv;
348 const u8 *start, *pos, *end;
351 u32 message_length = 0;
352 struct wpabuf tmpbuf;
354 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
357 return; /* Should not happen; message already verified */
368 if (eap_ikev2_process_icv(data, respData, flags, pos, &end) < 0) {
369 eap_ikev2_state(data, FAIL);
373 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
375 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
376 eap_ikev2_state(data, FAIL);
379 message_length = WPA_GET_BE32(pos);
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);
390 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
391 "Message Length %u", flags, message_length);
393 if (data->state == WAIT_FRAG_ACK) {
395 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
396 "in WAIT_FRAG_ACK state");
397 eap_ikev2_state(data, FAIL);
400 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
401 eap_ikev2_state(data, MSG);
405 if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
406 eap_ikev2_state(data, FAIL);
410 if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
411 if (eap_ikev2_process_fragment(data, flags, message_length,
413 eap_ikev2_state(data, FAIL);
415 eap_ikev2_state(data, FRAG_ACK);
417 } else if (data->state == FRAG_ACK) {
418 wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
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;
428 if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
429 if (data->in_buf == &tmpbuf)
431 eap_ikev2_state(data, FAIL);
435 switch (data->ikev2.state) {
437 /* SA_INIT was sent out, so message have to be
438 * integrity protected from now on. */
439 data->keys_ready = 1;
442 if (data->state == FAIL)
444 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
446 if (eap_ikev2_server_keymat(data))
448 eap_ikev2_state(data, DONE);
454 if (data->in_buf != &tmpbuf)
455 wpabuf_free(data->in_buf);
460 static Boolean eap_ikev2_isDone(struct eap_sm *sm, void *priv)
462 struct eap_ikev2_data *data = priv;
463 return data->state == DONE || data->state == FAIL;
467 static Boolean eap_ikev2_isSuccess(struct eap_sm *sm, void *priv)
469 struct eap_ikev2_data *data = priv;
470 return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
475 static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
477 struct eap_ikev2_data *data = priv;
480 if (data->state != DONE || !data->keymat_ok)
483 key = os_malloc(EAP_MSK_LEN);
485 os_memcpy(key, data->keymat, EAP_MSK_LEN);
493 static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
495 struct eap_ikev2_data *data = priv;
498 if (data->state != DONE || !data->keymat_ok)
501 key = os_malloc(EAP_EMSK_LEN);
503 os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
511 int eap_server_ikev2_register(void)
513 struct eap_method *eap;
516 eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
517 EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
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;
532 ret = eap_server_method_register(eap);
534 eap_server_method_free(eap);