6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
20 * Copyright 2001 hereUare Communications, Inc. <raghud@hereuare.com>
21 * Copyright 2003 Alan DeKok <aland@freeradius.org>
22 * Copyright 2006 The FreeRADIUS server project
27 * TLS Packet Format in EAP
28 * --- ------ ------ -- ---
30 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
31 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
32 * | Code | Identifier | Length |
33 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
34 * | Type | Flags | TLS Message Length
35 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36 * | TLS Message Length | TLS Data...
37 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42 USES_APPLE_DEPRECATED_API /* OpenSSL API has been deprecated by Apple */
48 * Send an initial eap-tls request to the peer.
50 * Frame eap reply packet.
51 * len = header + type + tls_typedata
52 * tls_typedata = flags(Start (S) bit set, and no data)
54 * Once having received the peer's Identity, the EAP server MUST
55 * respond with an EAP-TLS/Start packet, which is an
56 * EAP-Request packet with EAP-Type=EAP-TLS, the Start (S) bit
57 * set, and no data. The EAP-TLS conversation will then begin,
58 * with the peer sending an EAP-Response packet with
59 * EAP-Type = EAP-TLS. The data field of that packet will
62 * Fragment length is Framed-MTU - 4.
64 tls_session_t *eaptls_session(eap_handler_t *handler, fr_tls_server_conf_t *tls_conf, bool client_cert)
67 REQUEST *request = handler->request;
72 * Every new session is started only from EAP-TLS-START.
73 * Before Sending EAP-TLS-START, open a new SSL session.
74 * Create all the required data structures & store them
75 * in Opaque. So that we can use these data structures
76 * when we get the response
78 ssn = tls_new_session(handler, tls_conf, request, client_cert);
84 * Create a structure for all the items required to be
85 * verified for each client and set that as opaque data
88 * NOTE: If we want to set each item sepearately then
89 * this index should be global.
91 SSL_set_ex_data(ssn->ssl, FR_TLS_EX_INDEX_HANDLER, (void *)handler);
92 SSL_set_ex_data(ssn->ssl, FR_TLS_EX_INDEX_CONF, (void *)tls_conf);
93 SSL_set_ex_data(ssn->ssl, fr_tls_ex_index_certs, (void *)&(handler->certs));
94 SSL_set_ex_data(ssn->ssl, FR_TLS_EX_INDEX_IDENTITY, (void *)&(handler->identity));
95 #ifdef HAVE_OPENSSL_OCSP_H
96 SSL_set_ex_data(ssn->ssl, FR_TLS_EX_INDEX_STORE, (void *)tls_conf->ocsp_store);
98 SSL_set_ex_data(ssn->ssl, FR_TLS_EX_INDEX_SSN, (void *)ssn);
99 SSL_set_ex_data(ssn->ssl, FR_TLS_EX_INDEX_TALLOC, NULL);
101 return talloc_steal(handler, ssn); /* ssn */
105 The S flag is set only within the EAP-TLS start message
106 sent from the EAP server to the peer.
108 int eaptls_start(EAP_DS *eap_ds, int peap_flag)
112 reply.code = FR_TLS_START;
113 reply.length = TLS_HEADER_LEN + 1/*flags*/;
115 reply.flags = peap_flag;
116 reply.flags = SET_START(reply.flags);
121 eaptls_compose(eap_ds, &reply);
126 int eaptls_success(eap_handler_t *handler, int peap_flag)
129 REQUEST *request = handler->request;
130 tls_session_t *tls_session = handler->opaque;
132 handler->finished = true;
133 reply.code = FR_TLS_SUCCESS;
134 reply.length = TLS_HEADER_LEN;
135 reply.flags = peap_flag;
139 tls_success(tls_session, request);
142 * Call compose AFTER checking for cached data.
144 eaptls_compose(handler->eap_ds, &reply);
147 * Automatically generate MPPE keying material.
149 if (tls_session->prf_label) {
150 eaptls_gen_mppe_keys(handler->request,
151 tls_session->ssl, tls_session->prf_label);
153 RWDEBUG("Not adding MPPE keys because there is no PRF label");
156 eaptls_gen_eap_key(handler->request->reply, tls_session->ssl,
161 int eaptls_fail(eap_handler_t *handler, int peap_flag)
164 tls_session_t *tls_session = handler->opaque;
166 handler->finished = true;
167 reply.code = FR_TLS_FAIL;
168 reply.length = TLS_HEADER_LEN;
169 reply.flags = peap_flag;
173 tls_fail(tls_session);
175 eaptls_compose(handler->eap_ds, &reply);
181 A single TLS record may be up to 16384 octets in length, but a TLS
182 message may span multiple TLS records, and a TLS certificate message
183 may in principle be as long as 16MB.
187 * Frame the Dirty data that needs to be send to the client in an
188 * EAP-Request. We always embed the TLS-length in all EAP-TLS
189 * packets that we send, for easy reference purpose. Handle
190 * fragmentation and sending the next fragment etc.
192 int eaptls_request(EAP_DS *eap_ds, tls_session_t *ssn)
197 unsigned int lbit = 0;
199 /* This value determines whether we set (L)ength flag for
200 EVERY packet we send and add corresponding
201 "TLS Message Length" field.
204 This means we include L flag and "TLS Msg Len" in EVERY
208 This means we include L flag and "TLS Msg Len" **ONLY**
209 in First packet of a fragment series. We do not use
212 Having L flag in every packet is prefered.
215 if (ssn->length_flag) {
218 if (ssn->fragment == 0) {
219 ssn->tls_msg_len = ssn->dirty_out.used;
222 reply.code = FR_TLS_REQUEST;
223 reply.flags = ssn->peap_flag;
225 /* Send data, NOT more than the FRAGMENT size */
226 if (ssn->dirty_out.used > ssn->mtu) {
228 reply.flags = SET_MORE_FRAGMENTS(reply.flags);
229 /* Length MUST be included if it is the First Fragment */
230 if (ssn->fragment == 0) {
235 size = ssn->dirty_out.used;
239 reply.dlen = lbit + size;
240 reply.length = TLS_HEADER_LEN + 1/*flags*/ + reply.dlen;
242 reply.data = talloc_array(eap_ds, uint8_t, reply.length);
243 if (!reply.data) return 0;
246 nlen = htonl(ssn->tls_msg_len);
247 memcpy(reply.data, &nlen, lbit);
248 reply.flags = SET_LENGTH_INCLUDED(reply.flags);
250 (ssn->record_minus)(&ssn->dirty_out, reply.data + lbit, size);
252 eaptls_compose(eap_ds, &reply);
253 talloc_free(reply.data);
261 * Similarly, when the EAP server receives an EAP-Response with
262 * the M bit set, it MUST respond with an EAP-Request with
263 * EAP-Type=EAP-TLS and no data. This serves as a fragment ACK.
265 * In order to prevent errors in the processing of fragments, the
266 * EAP server MUST use increment the Identifier value for each
267 * fragment ACK contained within an EAP-Request, and the peer
268 * MUST include this Identifier value in the subsequent fragment
269 * contained within an EAP- Reponse.
271 * EAP server sends an ACK when it determines there are More
272 * fragments to receive to make the complete
273 * TLS-record/TLS-Message
275 static int eaptls_send_ack(eap_handler_t *handler, int peap_flag)
278 REQUEST *request = handler->request;
280 RDEBUG2("ACKing Peer's TLS record fragment");
281 reply.code = FR_TLS_ACK;
282 reply.length = TLS_HEADER_LEN + 1/*flags*/;
283 reply.flags = peap_flag;
287 eaptls_compose(handler->eap_ds, &reply);
293 * The S flag is set only within the EAP-TLS start message sent
294 * from the EAP server to the peer.
296 * Similarly, when the EAP server receives an EAP-Response with
297 * the M bit set, it MUST respond with an EAP-Request with
298 * EAP-Type=EAP-TLS and no data. This serves as a fragment
299 * ACK. The EAP peer MUST wait.
301 static fr_tls_status_t eaptls_verify(eap_handler_t *handler)
303 EAP_DS *eap_ds = handler->eap_ds;
304 tls_session_t *tls_session = handler->opaque;
305 EAP_DS *prev_eap_ds = handler->prev_eapds;
306 eaptls_packet_t *eaptls_packet, *eaptls_prev = NULL;
307 REQUEST *request = handler->request;
311 * We don't check ANY of the input parameters. It's all
312 * code which works together, so if something is wrong,
313 * we SHOULD core dump.
315 * e.g. if eap_ds is NULL, of if eap_ds->response is
316 * NULL, of if it's NOT an EAP-Response, or if the packet
317 * is too short. See eap_validation()., in ../../eap.c
319 * Also, eap_method_select() takes care of selecting the
320 * appropriate type, so we don't need to check
321 * eap_ds->response->type.num == PW_EAP_TLS, or anything
324 eaptls_packet = (eaptls_packet_t *)eap_ds->response->type.data;
325 if (prev_eap_ds && prev_eap_ds->response)
326 eaptls_prev = (eaptls_packet_t *)prev_eap_ds->response->type.data;
329 * First output the flags (for debugging)
331 RDEBUG3("Peer sent flags %c%c%c",
332 TLS_START(eaptls_packet->flags) ? 'S' : '-',
333 TLS_MORE_FRAGMENTS(eaptls_packet->flags) ? 'M' : '-',
334 TLS_LENGTH_INCLUDED(eaptls_packet->flags) ? 'L' : '-');
339 * If there's no TLS data, or there's 1 byte of TLS data,
340 * with the flags set to zero, then it's an ACK.
342 * Find if this is a reply to the previous request sent
344 if ((!eaptls_packet) ||
345 ((eap_ds->response->length == EAP_HEADER_LEN + 2) &&
346 ((eaptls_packet->flags & 0xc0) == 0x00))) {
348 if (prev_eap_ds && (prev_eap_ds->request->id == eap_ds->response->id)) {
349 return tls_ack_handler(handler->opaque, request);
351 REDEBUG("Received Invalid TLS ACK");
352 return FR_TLS_INVALID;
357 * We send TLS_START, but do not receive it.
359 if (TLS_START(eaptls_packet->flags)) {
360 REDEBUG("Peer sent EAP-TLS Start message (only the server is allowed to do this)");
361 return FR_TLS_INVALID;
365 * Calculate this fragment's length
367 frag_len = eap_ds->response->length -
368 (EAP_HEADER_LEN + (TLS_LENGTH_INCLUDED(eaptls_packet->flags) ? 6 : 2));
371 * The L bit (length included) is set to indicate the
372 * presence of the four octet TLS Message Length field,
373 * and MUST be set for the first fragment of a fragmented
374 * TLS message or set of messages.
376 * The M bit (more fragments) is set on all but the last
379 * The S bit (EAP-TLS start) is set in an EAP-TLS Start
380 * message. This differentiates the EAP-TLS Start message
381 * from a fragment acknowledgement.
383 if (TLS_LENGTH_INCLUDED(eaptls_packet->flags)) {
384 size_t total_len = eaptls_packet->data[2] * 256 | eaptls_packet->data[3];
386 if (frag_len > total_len) {
387 RWDEBUG("TLS fragment length (%zu bytes) greater than TLS record length (%zu bytes)", frag_len,
391 RDEBUG2("Peer indicated complete TLS record size will be %zu bytes", total_len);
392 if (TLS_MORE_FRAGMENTS(eaptls_packet->flags)) {
394 * The supplicant is free to send fragments of wildly varying
395 * lengths, but the vast majority won't.
397 * In this calculation we take into account the fact that the future
398 * fragments are likely to be 4 bytes larger than the initial one
399 * as they won't contain the length field.
401 if (frag_len + 4) { /* check for wrap, else clang scan gets excited */
402 RDEBUG2("Expecting %i TLS record fragments",
403 (int)((((total_len - frag_len) + ((frag_len + 4) - 1)) / (frag_len + 4)) + 1));
407 * FIRST_FRAGMENT is identified
408 * 1. If there is no previous EAP-response received.
409 * 2. If EAP-response received, then its M bit not set.
410 * (It is because Last fragment will not have M bit set)
412 if (!prev_eap_ds || (!prev_eap_ds->response) || (!eaptls_prev) ||
413 !TLS_MORE_FRAGMENTS(eaptls_prev->flags)) {
414 RDEBUG2("Got first TLS record fragment (%zu bytes). Peer indicated more fragments "
415 "to follow", frag_len);
416 tls_session->tls_record_in_total_len = total_len;
417 tls_session->tls_record_in_recvd_len = frag_len;
419 return FR_TLS_FIRST_FRAGMENT;
422 RDEBUG2("Got additional TLS record fragment with length (%zu bytes). "
423 "Peer indicated more fragments to follow", frag_len);
426 * Check we've not exceeded the originally indicated TLS record size.
428 tls_session->tls_record_in_recvd_len += frag_len;
429 if (tls_session->tls_record_in_recvd_len > tls_session->tls_record_in_total_len) {
430 RWDEBUG("Total received TLS record fragments (%zu bytes), exceeds "
431 "total TLS record length (%zu bytes)", frag_len, total_len);
434 return FR_TLS_MORE_FRAGMENTS_WITH_LENGTH;
438 * If it's a complete record, our fragment size should match the
439 * value of the four octet TLS length field.
441 if (total_len != frag_len) {
442 RWDEBUG("Peer indicated no more fragments, but TLS record length (%zu bytes) "
443 "does not match EAP-TLS data length (%zu bytes)", total_len, frag_len);
446 tls_session->tls_record_in_total_len = total_len;
447 tls_session->tls_record_in_recvd_len = frag_len;
448 RDEBUG2("Got complete TLS record (%zu bytes)", frag_len);
449 return FR_TLS_LENGTH_INCLUDED;
453 * The previous packet had the M flags set, but this one doesn't,
454 * this must be the final record fragment
456 if ((eaptls_prev && TLS_MORE_FRAGMENTS(eaptls_prev->flags)) && !TLS_MORE_FRAGMENTS(eaptls_packet->flags)) {
457 RDEBUG2("Got final TLS record fragment (%zu bytes)", frag_len);
458 tls_session->tls_record_in_recvd_len += frag_len;
459 if (tls_session->tls_record_in_recvd_len != tls_session->tls_record_in_total_len) {
460 RWDEBUG("Total received TLS record fragments (%zu bytes), does not equal indicated "
461 "TLS record length (%zu bytes)",
462 tls_session->tls_record_in_recvd_len, tls_session->tls_record_in_total_len);
466 if (TLS_MORE_FRAGMENTS(eaptls_packet->flags)) {
467 RDEBUG2("Got additional TLS record fragment (%zu bytes). Peer indicated more fragments to follow",
469 tls_session->tls_record_in_recvd_len += frag_len;
470 if (tls_session->tls_record_in_recvd_len > tls_session->tls_record_in_total_len) {
471 RWDEBUG("Total received TLS record fragments (%zu bytes), exceeds "
472 "indicated TLS record length (%zu bytes)",
473 tls_session->tls_record_in_recvd_len, tls_session->tls_record_in_total_len);
475 return FR_TLS_MORE_FRAGMENTS;
479 * None of the flags are set, but it's still a valid EAP-TLS packet.
488 * length = code + id + length + flags + tlsdata
489 * = 1 + 1 + 2 + 1 + X
490 * length = EAP-length - 1(EAP-Type = 1 octet)
491 * flags = EAP-typedata[0] (1 octet)
492 * dlen = EAP-typedata[1-4] (4 octets), if L flag set
493 * = length - 5(code+id+length+flags), otherwise
494 * data = EAP-typedata[5-n], if L flag set
495 * = EAP-typedata[1-n], otherwise
496 * packet = EAP-typedata (complete typedata)
498 * Points to consider during EAP-TLS data extraction
499 * 1. In the received packet, No data will be present incase of ACK-NAK
500 * 2. Incase if more fragments need to be received then ACK after retreiving this fragment.
502 * RFC 2716 Section 4.2. PPP EAP TLS Request Packet
505 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
506 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
507 * | Code | Identifier | Length |
508 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
509 * | Type | Flags | TLS Message Length
510 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
511 * | TLS Message Length | TLS Data...
512 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
514 * The Length field is two octets and indicates the length of the EAP
515 * packet including the Code, Identifir, Length, Type, and TLS data
518 static EAPTLS_PACKET *eaptls_extract(REQUEST *request, EAP_DS *eap_ds, fr_tls_status_t status)
520 EAPTLS_PACKET *tlspacket;
521 uint32_t data_len = 0;
523 uint8_t *data = NULL;
525 if (status == FR_TLS_INVALID) return NULL;
528 * The main EAP code & eaptls_verify() take care of
529 * ensuring that the packet is OK, and that we can
530 * extract the various fields we want.
532 * e.g. a TLS packet with zero data is allowed as an ACK,
533 * but we will never see it here, as we will simply
534 * send another fragment, instead of trying to extract
537 * MUST have TLS type octet, followed by flags, followed
540 assert(eap_ds->response->length > 2);
542 tlspacket = talloc(eap_ds, EAPTLS_PACKET);
543 if (!tlspacket) return NULL;
546 * Code & id for EAPTLS & EAP are same
547 * but eaptls_length = eap_length - 1(EAP-Type = 1 octet)
549 * length = code + id + length + type + tlsdata
550 * = 1 + 1 + 2 + 1 + X
552 tlspacket->code = eap_ds->response->code;
553 tlspacket->id = eap_ds->response->id;
554 tlspacket->length = eap_ds->response->length - 1; /* EAP type */
555 tlspacket->flags = eap_ds->response->type.data[0];
558 * A quick sanity check of the flags. If we've been told
559 * that there's a length, and there isn't one, then stop.
561 if (TLS_LENGTH_INCLUDED(tlspacket->flags) &&
562 (tlspacket->length < 5)) { /* flags + TLS message length */
563 REDEBUG("Invalid EAP-TLS packet received: Length bit is set, "
564 "but packet too short to contain length field");
565 talloc_free(tlspacket);
570 * If the final TLS packet is larger than we can handle, die
573 * Likewise, if the EAP packet says N bytes, and the TLS
574 * packet says there's fewer bytes, it's a problem.
576 if (TLS_LENGTH_INCLUDED(tlspacket->flags)) {
577 memcpy(&data_len, &eap_ds->response->type.data[1], 4);
578 data_len = ntohl(data_len);
579 if (data_len > MAX_RECORD_SIZE) {
580 REDEBUG("Reassembled TLS record will be %u bytes, "
581 "greater than our maximum record size (" STRINGIFY(MAX_RECORD_SIZE) " bytes)",
583 talloc_free(tlspacket);
590 * The TLS Message Length field is four octets, and
591 * provides the total length of the TLS message or set of
592 * messages that is being fragmented; this simplifies
595 * Dynamic allocation of buffers as & when we know the
596 * length should solve the problem.
598 case FR_TLS_FIRST_FRAGMENT:
599 case FR_TLS_LENGTH_INCLUDED:
600 case FR_TLS_MORE_FRAGMENTS_WITH_LENGTH:
601 if (tlspacket->length < 5) { /* flags + TLS message length */
602 REDEBUG("Invalid EAP-TLS packet received: Expected length, got none");
603 talloc_free(tlspacket);
608 * Extract all the TLS fragments from the
609 * previous eap_ds Start appending this
610 * fragment to the above ds
612 memcpy(&data_len, &eap_ds->response->type.data[1], sizeof(uint32_t));
613 data_len = ntohl(data_len);
614 data = (eap_ds->response->type.data + 5/*flags+TLS-Length*/);
615 len = eap_ds->response->type.length - 5/*flags+TLS-Length*/;
618 * Hmm... this should be an error, too.
620 if (data_len > len) {
626 * Data length is implicit, from the EAP header.
628 case FR_TLS_MORE_FRAGMENTS:
630 data_len = eap_ds->response->type.length - 1/*flags*/;
631 data = eap_ds->response->type.data + 1/*flags*/;
635 REDEBUG("Invalid EAP-TLS packet received");
636 talloc_free(tlspacket);
640 tlspacket->dlen = data_len;
642 tlspacket->data = talloc_array(tlspacket, uint8_t,
644 if (!tlspacket->data) {
645 talloc_free(tlspacket);
648 memcpy(tlspacket->data, data, data_len);
657 * To process the TLS,
659 * 1. EAP-TLS should get the compelete TLS data from the peer.
660 * 2. Store that data in a data structure with any other required info
661 * 3. Handle that data structure to the TLS module.
662 * 4. TLS module will perform its operations on the data and
663 * handle back to EAP-TLS
666 * 1. EAP-TLS if necessary will fragment it and send it to the
669 * During EAP-TLS initialization, TLS Context object will be
670 * initialized and stored. For every new authentication
671 * requests, TLS will open a new session object and that session
672 * object should be maintained even after the session is
673 * completed for session resumption. (Probably later as a feature
674 * as we donot know who maintains these session objects ie,
675 * SSL_CTX (internally) or TLS module(explicitly). If TLS module,
676 * then how to let SSL API know about these sessions.)
678 static fr_tls_status_t eaptls_operation(fr_tls_status_t status, eap_handler_t *handler)
680 REQUEST *request = handler->request;
681 tls_session_t *tls_session = handler->opaque;
683 if ((status == FR_TLS_MORE_FRAGMENTS) ||
684 (status == FR_TLS_MORE_FRAGMENTS_WITH_LENGTH) ||
685 (status == FR_TLS_FIRST_FRAGMENT)) {
689 eaptls_send_ack(handler, tls_session->peap_flag);
690 return FR_TLS_HANDLED;
695 * We have the complete TLS-data or TLS-message.
697 * Clean the dirty message.
699 * Authenticate the user and send
703 * is required then send another request.
705 if (!tls_handshake_recv(handler->request, tls_session)) {
706 REDEBUG("TLS receive handshake failed during operation");
707 tls_fail(tls_session);
712 * FIXME: return success/fail.
714 * TLS proper can decide what to do, then.
716 if (tls_session->dirty_out.used > 0) {
717 eaptls_request(handler->eap_ds, tls_session);
718 return FR_TLS_HANDLED;
722 * If there is no data to send i.e
723 * dirty_out.used <=0 and if the SSL
724 * handshake is finished, then return a
728 if (SSL_is_init_finished(tls_session->ssl)) {
730 * Init is finished. The rest is
733 tls_session->info.content_type = application_data;
734 return FR_TLS_SUCCESS;
738 * Who knows what happened...
740 REDEBUG("TLS failed during operation");
746 * In the actual authentication first verify the packet and then create the data structure
749 * To process the TLS,
751 * 1. EAP-TLS should get the compelete TLS data from the peer.
752 * 2. Store that data in a data structure with any other required info
753 * 3. Hand this data structure to the TLS module.
754 * 4. TLS module will perform its operations on the data and hands back to EAP-TLS
756 * 1. EAP-TLS if necessary will fragment it and send it to the destination.
758 * During EAP-TLS initialization, TLS Context object will be
759 * initialized and stored. For every new authentication
760 * requests, TLS will open a new session object and that
761 * session object SHOULD be maintained even after the session
762 * is completed, for session resumption. (Probably later as a
763 * feature, as we do not know who maintains these session
764 * objects ie, SSL_CTX (internally) or TLS module (explicitly). If
765 * TLS module, then how to let SSL API know about these
770 * Process an EAP request
772 fr_tls_status_t eaptls_process(eap_handler_t *handler)
774 tls_session_t *tls_session = (tls_session_t *) handler->opaque;
775 EAPTLS_PACKET *tlspacket;
776 fr_tls_status_t status;
777 REQUEST *request = handler->request;
779 if (!request) return FR_TLS_FAIL;
781 RDEBUG2("Continuing EAP-TLS");
783 SSL_set_ex_data(tls_session->ssl, FR_TLS_EX_INDEX_REQUEST, request);
785 if (handler->certs) fr_pair_add(&request->packet->vps,
786 fr_pair_list_copy(request->packet, handler->certs));
789 * This case is when SSL generates Alert then we
790 * send that alert to the client and then send the EAP-Failure
792 status = eaptls_verify(handler);
793 if ((status == FR_TLS_INVALID) || (status == FR_TLS_FAIL)) {
794 REDEBUG("[eaptls verify] = %s", fr_int2str(fr_tls_status_table, status, "<INVALID>"));
796 RDEBUG2("[eaptls verify] = %s", fr_int2str(fr_tls_status_table, status, "<INVALID>"));
805 * Success means that we're done the initial
806 * handshake. For TTLS, this means send stuff
807 * back to the client, and the client sends us
808 * more tunneled data.
814 * Normal TLS request, continue with the "get rest
815 * of fragments" phase.
818 eaptls_request(handler->eap_ds, tls_session);
819 status = FR_TLS_HANDLED;
823 * The handshake is done, and we're in the "tunnel
827 RDEBUG2("Done initial handshake");
830 * Get the rest of the fragments.
832 case FR_TLS_FIRST_FRAGMENT:
833 case FR_TLS_MORE_FRAGMENTS:
834 case FR_TLS_LENGTH_INCLUDED:
835 case FR_TLS_MORE_FRAGMENTS_WITH_LENGTH:
840 * Extract the TLS packet from the buffer.
842 if ((tlspacket = eaptls_extract(request, handler->eap_ds, status)) == NULL) {
843 status = FR_TLS_FAIL;
848 * Get the session struct from the handler
850 * update the dirty_in buffer
852 * NOTE: This buffer will contain partial data when M bit is set.
854 * CAUTION while reinitializing this buffer, it should be
855 * reinitialized only when this M bit is NOT set.
857 if (tlspacket->dlen !=
858 (tls_session->record_plus)(&tls_session->dirty_in, tlspacket->data, tlspacket->dlen)) {
859 talloc_free(tlspacket);
860 REDEBUG("Exceeded maximum record size");
861 status = FR_TLS_FAIL;
868 talloc_free(tlspacket);
871 * SSL initalization is done. Return.
873 * The TLS data will be in the tls_session structure.
875 if (SSL_is_init_finished(tls_session->ssl)) {
877 * The initialization may be finished, but if
878 * there more fragments coming, then send ACK,
879 * and get the caller to continue the
882 if ((status == FR_TLS_MORE_FRAGMENTS) ||
883 (status == FR_TLS_MORE_FRAGMENTS_WITH_LENGTH) ||
884 (status == FR_TLS_FIRST_FRAGMENT)) {
888 eaptls_send_ack(handler, tls_session->peap_flag);
889 RDEBUG2("Init is done, but tunneled data is fragmented");
890 status = FR_TLS_HANDLED;
894 status = tls_application_data(tls_session, request);
899 * Continue the handshake.
901 status = eaptls_operation(status, handler);
902 if (status == FR_TLS_SUCCESS) {
903 #define MAX_SESSION_SIZE (256)
905 char buffer[2 * MAX_SESSION_SIZE + 1];
908 * Restore the cached VPs before processing the
911 tls_session_id(tls_session->ssl_session, buffer, MAX_SESSION_SIZE);
913 vps = SSL_SESSION_get_ex_data(tls_session->ssl_session, fr_tls_ex_index_vps);
915 RWDEBUG("No information in cached session %s", buffer);
920 RDEBUG("Adding cached attributes from session %s", buffer);
923 * The cbtls_get_session() function doesn't have
924 * access to sock->certs or handler->certs, which
925 * is where the certificates normally live. So
926 * the certs are all in the VPS list here, and
927 * have to be manually extracted.
930 for (vp = fr_cursor_init(&cursor, &vps);
932 vp = fr_cursor_next(&cursor)) {
934 * TLS-* attrs get added back to
937 if ((vp->da->vendor == 0) &&
938 (vp->da->attr >= PW_TLS_CERT_SERIAL) &&
939 (vp->da->attr <= PW_TLS_CLIENT_CERT_SUBJECT_ALT_NAME_UPN)) {
941 * Certs already exist. Don't re-add them.
943 if (!handler->certs) {
944 rdebug_pair(L_DBG_LVL_2, request, vp, "request:");
945 fr_pair_add(&request->packet->vps, fr_pair_copy(request->packet, vp));
948 rdebug_pair(L_DBG_LVL_2, request, vp, "reply:");
949 fr_pair_add(&request->reply->vps, fr_pair_copy(request->reply, vp));
957 SSL_set_ex_data(tls_session->ssl, FR_TLS_EX_INDEX_REQUEST, NULL);
964 * compose the TLS reply packet in the EAP reply typedata
966 int eaptls_compose(EAP_DS *eap_ds, EAPTLS_PACKET *reply)
971 * Don't set eap_ds->request->type.num, as the main EAP
972 * handler will do that for us. This allows the TLS
973 * module to be called from TTLS & PEAP.
977 * When the EAP server receives an EAP-Response with the
978 * M bit set, it MUST respond with an EAP-Request with
979 * EAP-Type=EAP-TLS and no data. This serves as a
980 * fragment ACK. The EAP peer MUST wait until it receives
981 * the EAP-Request before sending another fragment.
983 * In order to prevent errors in the processing of
984 * fragments, the EAP server MUST use increment the
985 * Identifier value for each fragment ACK contained
986 * within an EAP-Request, and the peer MUST include this
987 * Identifier value in the subsequent fragment contained
988 * within an EAP- Reponse.
990 eap_ds->request->type.data = talloc_array(eap_ds->request, uint8_t,
991 reply->length - TLS_HEADER_LEN + 1);
992 if (!eap_ds->request->type.data) return 0;
994 /* EAPTLS Header length is excluded while computing EAP typelen */
995 eap_ds->request->type.length = reply->length - TLS_HEADER_LEN;
997 ptr = eap_ds->request->type.data;
998 *ptr++ = (uint8_t)(reply->flags & 0xFF);
1000 if (reply->dlen) memcpy(ptr, reply->data, reply->dlen);
1002 switch (reply->code) {
1005 case FR_TLS_REQUEST:
1006 eap_ds->request->code = PW_EAP_REQUEST;
1009 case FR_TLS_SUCCESS:
1010 eap_ds->request->code = PW_EAP_SUCCESS;
1014 eap_ds->request->code = PW_EAP_FAILURE;
1018 /* Should never enter here */
1027 * Parse TLS configuration
1029 * If the option given by 'attr' is set, we find the config section
1030 * of that name and use that for the TLS configuration. If not, we
1031 * fall back to compatibility mode and read the TLS options from
1032 * the 'tls' section.
1034 fr_tls_server_conf_t *eaptls_conf_parse(CONF_SECTION *cs, char const *attr)
1036 char const *tls_conf_name;
1038 CONF_SECTION *parent;
1039 CONF_SECTION *tls_cs;
1040 fr_tls_server_conf_t *tls_conf;
1045 rad_assert(attr != NULL);
1047 parent = cf_item_parent(cf_section_to_item(cs));
1049 cp = cf_pair_find(cs, attr);
1051 tls_conf_name = cf_pair_value(cp);
1053 tls_cs = cf_section_sub_find_name2(parent, TLS_CONFIG_SECTION, tls_conf_name);
1056 ERROR("Cannot find tls config \"%s\"", tls_conf_name);
1061 * If we can't find the section given by the 'attr', we
1062 * fall-back to looking for the "tls" section, as in
1063 * previous versions.
1065 * We don't fall back if the 'attr' is specified, but we can't
1066 * find the section - that is just a config error.
1068 INFO("TLS section \"%s\" missing, trying to use legacy configuration", attr);
1069 tls_cs = cf_section_sub_find(parent, "tls");
1075 tls_conf = tls_server_conf_parse(tls_cs);
1081 * The EAP RFC's say 1020, but we're less picky.
1083 if (tls_conf->fragment_size < 100) {
1084 ERROR("Configured fragment size is too small, must be >= 100");
1089 * The maximum size for a RADIUS packet is 4096,
1090 * minus the header (20), Message-Authenticator (18),
1091 * and State (18), etc. results in about 4000 bytes of data
1092 * that can be devoted *solely* to EAP.
1094 if (tls_conf->fragment_size > 4000) {
1095 ERROR("Configured fragment size is too large, must be <= 4000");
1100 * Account for the EAP header (4), and the EAP-TLS header
1101 * (6), as per Section 4.2 of RFC 2716. What's left is
1102 * the maximum amount of data we read from a TLS buffer.
1104 tls_conf->fragment_size -= 10;