2 * EAP-IKEv2 peer (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_responder_data ikev2;
25 enum { WAIT_START, PROC_MSG, 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 char * eap_ikev2_state_txt(int state)
44 return "WAIT_FRAG_ACK";
55 static void eap_ikev2_state(struct eap_ikev2_data *data, int state)
57 wpa_printf(MSG_DEBUG, "EAP-IKEV2: %s -> %s",
58 eap_ikev2_state_txt(data->state),
59 eap_ikev2_state_txt(state));
64 static void * eap_ikev2_init(struct eap_sm *sm)
66 struct eap_ikev2_data *data;
67 const u8 *identity, *password;
68 size_t identity_len, password_len;
70 identity = eap_get_config_identity(sm, &identity_len);
71 if (identity == NULL) {
72 wpa_printf(MSG_INFO, "EAP-IKEV2: No identity available");
76 data = os_zalloc(sizeof(*data));
79 data->state = WAIT_START;
80 data->fragment_size = IKEV2_FRAGMENT_SIZE;
81 data->ikev2.state = SA_INIT;
82 data->ikev2.peer_auth = PEER_AUTH_SECRET;
83 data->ikev2.key_pad = (u8 *) os_strdup("Key Pad for EAP-IKEv2");
84 if (data->ikev2.key_pad == NULL)
86 data->ikev2.key_pad_len = 21;
87 data->ikev2.IDr = os_malloc(identity_len);
88 if (data->ikev2.IDr == NULL)
90 os_memcpy(data->ikev2.IDr, identity, identity_len);
91 data->ikev2.IDr_len = identity_len;
93 password = eap_get_config_password(sm, &password_len);
95 data->ikev2.shared_secret = os_malloc(password_len);
96 if (data->ikev2.shared_secret == NULL)
98 os_memcpy(data->ikev2.shared_secret, password, password_len);
99 data->ikev2.shared_secret_len = password_len;
105 ikev2_responder_deinit(&data->ikev2);
111 static void eap_ikev2_deinit(struct eap_sm *sm, void *priv)
113 struct eap_ikev2_data *data = priv;
114 wpabuf_free(data->in_buf);
115 wpabuf_free(data->out_buf);
116 ikev2_responder_deinit(&data->ikev2);
121 static int eap_ikev2_peer_keymat(struct eap_ikev2_data *data)
123 if (eap_ikev2_derive_keymat(
124 data->ikev2.proposal.prf, &data->ikev2.keys,
125 data->ikev2.i_nonce, data->ikev2.i_nonce_len,
126 data->ikev2.r_nonce, data->ikev2.r_nonce_len,
128 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to "
129 "derive key material");
137 static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data,
138 struct eap_method_ret *ret, u8 id)
142 size_t send_len, plen, icv_len = 0;
145 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Response");
146 ret->allowNotifications = TRUE;
149 send_len = wpabuf_len(data->out_buf) - data->out_used;
150 if (1 + send_len > data->fragment_size) {
151 send_len = data->fragment_size - 1;
152 flags |= IKEV2_FLAGS_MORE_FRAGMENTS;
153 if (data->out_used == 0) {
154 flags |= IKEV2_FLAGS_LENGTH_INCLUDED;
159 /* Some issues figuring out the length of the message if Message Length
160 * field not included?! */
161 if (!(flags & IKEV2_FLAGS_LENGTH_INCLUDED))
162 flags |= IKEV2_FLAGS_LENGTH_INCLUDED;
166 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
168 if (data->keys_ready) {
169 const struct ikev2_integ_alg *integ;
170 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
172 flags |= IKEV2_FLAGS_ICV_INCLUDED;
173 integ = ikev2_get_integ(data->ikev2.proposal.integ);
175 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
176 "transform / cannot generate ICV");
179 icv_len = integ->hash_len;
183 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
184 EAP_CODE_RESPONSE, id);
188 wpabuf_put_u8(resp, flags); /* Flags */
189 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
190 wpabuf_put_be32(resp, wpabuf_len(data->out_buf));
192 wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
194 data->out_used += send_len;
196 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
197 const u8 *msg = wpabuf_head(resp);
198 size_t len = wpabuf_len(resp);
199 ikev2_integ_hash(data->ikev2.proposal.integ,
200 data->ikev2.keys.SK_ar,
201 data->ikev2.keys.SK_integ_len,
202 msg, len, wpabuf_put(resp, icv_len));
205 ret->methodState = METHOD_MAY_CONT;
206 ret->decision = DECISION_FAIL;
208 if (data->out_used == wpabuf_len(data->out_buf)) {
209 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
210 "(message sent completely)",
211 (unsigned long) send_len);
212 wpabuf_free(data->out_buf);
213 data->out_buf = NULL;
215 switch (data->ikev2.state) {
217 /* SA_INIT was sent out, so message have to be
218 * integrity protected from now on. */
219 data->keys_ready = 1;
222 ret->methodState = METHOD_DONE;
223 if (data->state == FAIL)
225 ret->decision = DECISION_COND_SUCC;
226 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication "
227 "completed successfully");
228 if (eap_ikev2_peer_keymat(data))
230 eap_ikev2_state(data, DONE);
233 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication "
235 ret->methodState = METHOD_DONE;
236 ret->decision = DECISION_FAIL;
242 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
243 "(%lu more to send)", (unsigned long) send_len,
244 (unsigned long) wpabuf_len(data->out_buf) -
246 eap_ikev2_state(data, WAIT_FRAG_ACK);
253 static int eap_ikev2_process_icv(struct eap_ikev2_data *data,
254 const struct wpabuf *reqData,
255 u8 flags, const u8 *pos, const u8 **end)
257 if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
258 int icv_len = eap_ikev2_validate_icv(
259 data->ikev2.proposal.integ, &data->ikev2.keys, 1,
263 /* Hide Integrity Checksum Data from further processing */
265 } else if (data->keys_ready) {
266 wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
267 "included integrity checksum");
275 static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
276 const u8 *buf, size_t len)
278 /* Process continuation of a pending message */
279 if (len > wpabuf_tailroom(data->in_buf)) {
280 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
281 eap_ikev2_state(data, FAIL);
285 wpabuf_put_data(data->in_buf, buf, len);
286 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting "
287 "for %lu bytes more", (unsigned long) len,
288 (unsigned long) wpabuf_tailroom(data->in_buf));
294 static struct wpabuf * eap_ikev2_process_fragment(struct eap_ikev2_data *data,
295 struct eap_method_ret *ret,
298 const u8 *buf, size_t len)
300 /* Process a fragment that is not the last one of the message */
301 if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
302 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
303 "a fragmented packet");
308 if (data->in_buf == NULL) {
309 /* First fragment of the message */
310 data->in_buf = wpabuf_alloc(message_length);
311 if (data->in_buf == NULL) {
312 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));
324 return eap_ikev2_build_frag_ack(id, EAP_CODE_RESPONSE);
328 static struct wpabuf * eap_ikev2_process(struct eap_sm *sm, void *priv,
329 struct eap_method_ret *ret,
330 const struct wpabuf *reqData)
332 struct eap_ikev2_data *data = priv;
333 const u8 *start, *pos, *end;
336 u32 message_length = 0;
337 struct wpabuf tmpbuf;
339 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, reqData, &len);
345 id = eap_get_id(reqData);
351 flags = 0; /* fragment ack */
355 if (eap_ikev2_process_icv(data, reqData, flags, pos, &end) < 0) {
360 if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
362 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
366 message_length = WPA_GET_BE32(pos);
369 if (message_length < (u32) (end - pos)) {
370 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
371 "Length (%d; %ld remaining in this msg)",
372 message_length, (long) (end - pos));
378 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
379 "Message Length %u", flags, message_length);
381 if (data->state == WAIT_FRAG_ACK) {
383 if (len > 1) /* Empty Flags field included in ACK */
388 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
389 "in WAIT_FRAG_ACK state");
393 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
394 eap_ikev2_state(data, PROC_MSG);
395 return eap_ikev2_build_msg(data, ret, id);
398 if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
403 if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
404 return eap_ikev2_process_fragment(data, ret, id, flags,
409 if (data->in_buf == NULL) {
410 /* Wrap unfragmented messages as wpabuf without extra copy */
411 wpabuf_set(&tmpbuf, pos, end - pos);
412 data->in_buf = &tmpbuf;
415 if (ikev2_responder_process(&data->ikev2, data->in_buf) < 0) {
416 if (data->in_buf == &tmpbuf)
418 eap_ikev2_state(data, FAIL);
422 if (data->in_buf != &tmpbuf)
423 wpabuf_free(data->in_buf);
426 if (data->out_buf == NULL) {
427 data->out_buf = ikev2_responder_build(&data->ikev2);
428 if (data->out_buf == NULL) {
429 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to generate "
436 eap_ikev2_state(data, PROC_MSG);
437 return eap_ikev2_build_msg(data, ret, id);
441 static Boolean eap_ikev2_isKeyAvailable(struct eap_sm *sm, void *priv)
443 struct eap_ikev2_data *data = priv;
444 return data->state == DONE && data->keymat_ok;
448 static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
450 struct eap_ikev2_data *data = priv;
453 if (data->state != DONE || !data->keymat_ok)
456 key = os_malloc(EAP_MSK_LEN);
458 os_memcpy(key, data->keymat, EAP_MSK_LEN);
466 static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
468 struct eap_ikev2_data *data = priv;
471 if (data->state != DONE || !data->keymat_ok)
474 key = os_malloc(EAP_EMSK_LEN);
476 os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
484 int eap_peer_ikev2_register(void)
486 struct eap_method *eap;
489 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
490 EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
495 eap->init = eap_ikev2_init;
496 eap->deinit = eap_ikev2_deinit;
497 eap->process = eap_ikev2_process;
498 eap->isKeyAvailable = eap_ikev2_isKeyAvailable;
499 eap->getKey = eap_ikev2_getKey;
500 eap->get_emsk = eap_ikev2_get_emsk;
502 ret = eap_peer_method_register(eap);
504 eap_peer_method_free(eap);