1 /* * eap-tls.c - EAP-TLS implementation for PPP
3 * Copyright (c) Beniamino Galvani 2005 All rights reserved.
4 * Jan Just Keijser 2006-2019 All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
18 * 3. The name(s) of the authors of this software must not be used to
19 * endorse or promote products derived from this software without
20 * prior written permission.
22 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
23 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
24 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
26 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
27 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
28 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
35 #include <sys/types.h>
39 #include <openssl/conf.h>
40 #include <openssl/engine.h>
41 #include <openssl/hmac.h>
42 #include <openssl/err.h>
43 #include <openssl/ui.h>
44 #include <openssl/x509v3.h>
45 #include <openssl/pkcs12.h>
54 #include "pathnames.h"
56 typedef struct pw_cb_data
59 const char *prompt_info;
62 #ifndef OPENSSL_NO_ENGINE
63 /* The openssl configuration file and engines can be loaded only once */
64 static CONF *ssl_config = NULL;
65 static ENGINE *cert_engine = NULL;
66 static ENGINE *pkey_engine = NULL;
69 /* TLSv1.3 do we have a session ticket ? */
70 static int have_session_ticket = 0;
72 int ssl_verify_callback(int, X509_STORE_CTX *);
73 void ssl_msg_callback(int write_p, int version, int ct, const void *buf,
74 size_t len, SSL * ssl, void *arg);
75 int ssl_new_session_cb(SSL *s, SSL_SESSION *sess);
77 X509 *get_X509_from_file(char *filename);
78 int ssl_cmp_certs(char *filename, X509 * a);
81 * OpenSSL 1.1+ introduced a generic TLS_method()
82 * For older releases we substitute the appropriate method
85 #if OPENSSL_VERSION_NUMBER < 0x10100000L
87 #define TLS_method SSLv23_method
89 #define SSL3_RT_HEADER 0x100
91 #ifndef SSL_CTX_set_max_proto_version
92 /** Mimics SSL_CTX_set_max_proto_version for OpenSSL < 1.1 */
93 static inline int SSL_CTX_set_max_proto_version(SSL_CTX *ctx, long tls_ver_max)
97 if (tls_ver_max < TLS1_VERSION)
99 sslopt |= SSL_OP_NO_TLSv1;
101 #ifdef SSL_OP_NO_TLSv1_1
102 if (tls_ver_max < TLS1_1_VERSION)
104 sslopt |= SSL_OP_NO_TLSv1_1;
107 #ifdef SSL_OP_NO_TLSv1_2
108 if (tls_ver_max < TLS1_2_VERSION)
110 sslopt |= SSL_OP_NO_TLSv1_2;
113 SSL_CTX_set_options(ctx, sslopt);
117 #endif /* SSL_CTX_set_max_proto_version */
119 #endif /* OPENSSL_VERSION_NUMBER < 0x10100000L */
122 #define EAPTLS_MPPE_KEY_LEN 32
125 * Generate keys according to RFC 2716 and add to reply
127 void eaptls_gen_mppe_keys(struct eaptls_session *ets, int client)
129 unsigned char out[4*EAPTLS_MPPE_KEY_LEN];
130 const char *prf_label;
132 unsigned char eap_tls13_context[] = { EAPT_TLS };
133 unsigned char *context = NULL;
134 size_t context_len = 0;
137 dbglog("EAP-TLS generating MPPE keys");
140 prf_label = "EXPORTER_EAP_TLS_Key_Material";
141 context = eap_tls13_context;
146 prf_label = "client EAP encryption";
149 dbglog("EAP-TLS PRF label = %s", prf_label);
150 prf_size = strlen(prf_label);
151 if (SSL_export_keying_material(ets->ssl, out, sizeof(out), prf_label, prf_size,
152 context, context_len, 0) != 1)
154 warn( "EAP-TLS: Failed generating keying material" );
159 * We now have the master send and receive keys.
160 * From these, generate the session send and receive keys.
161 * (see RFC3079 / draft-ietf-pppext-mppe-keys-03.txt for details)
165 mppe_set_keys(out, out + EAPTLS_MPPE_KEY_LEN, EAPTLS_MPPE_KEY_LEN);
169 mppe_set_keys(out + EAPTLS_MPPE_KEY_LEN, out, EAPTLS_MPPE_KEY_LEN);
176 void log_ssl_errors( void )
178 unsigned long ssl_err = ERR_get_error();
181 dbglog("EAP-TLS SSL error stack:");
182 while (ssl_err != 0) {
183 dbglog( ERR_error_string( ssl_err, NULL ) );
184 ssl_err = ERR_get_error();
189 int password_callback (char *buf, int size, int rwflag, void *u)
193 strlcpy (buf, passwd, size);
200 CONF *eaptls_ssl_load_config( void )
204 long error_line = 33;
206 config = NCONF_new( NULL );
207 dbglog( "Loading OpenSSL config file" );
208 ret_code = NCONF_load( config, _PATH_OPENSSLCONFFILE, &error_line );
211 warn( "EAP-TLS: Error in OpenSSL config file %s at line %d", _PATH_OPENSSLCONFFILE, error_line );
212 NCONF_free( config );
217 dbglog( "Loading OpenSSL built-ins" );
218 #ifndef OPENSSL_NO_ENGINE
219 ENGINE_load_builtin_engines();
221 OPENSSL_load_builtin_modules();
223 dbglog( "Loading OpenSSL configured modules" );
224 if (CONF_modules_load( config, NULL, 0 ) <= 0 )
226 warn( "EAP-TLS: Error loading OpenSSL modules" );
234 #ifndef OPENSSL_NO_ENGINE
235 ENGINE *eaptls_ssl_load_engine( char *engine_name )
239 dbglog( "Enabling OpenSSL auto engines" );
240 ENGINE_register_all_complete();
242 dbglog( "Loading OpenSSL '%s' engine support", engine_name );
243 e = ENGINE_by_id( engine_name );
246 dbglog( "EAP-TLS: Cannot load '%s' engine support, trying 'dynamic'", engine_name );
247 e = ENGINE_by_id( "dynamic" );
250 if (!ENGINE_ctrl_cmd_string(e, "SO_PATH", engine_name, 0)
251 || !ENGINE_ctrl_cmd_string(e, "LOAD", NULL, 0))
253 warn( "EAP-TLS: Error loading dynamic engine '%s'", engine_name );
261 warn( "EAP-TLS: Cannot load dynamic engine support" );
267 dbglog( "Initialising engine" );
268 if(!ENGINE_set_default(e, ENGINE_METHOD_ALL))
270 warn( "EAP-TLS: Cannot use that engine" );
283 * Initialize the SSL stacks and tests if certificates, key and crl
284 * for client or server use can be loaded.
286 SSL_CTX *eaptls_init_ssl(int init_server, char *cacertfile, char *capath,
287 char *certfile, char *peer_certfile, char *privkeyfile, char *pkcs12)
289 #ifndef OPENSSL_NO_ENGINE
290 char *cert_engine_name = NULL;
291 char *cert_identifier = NULL;
292 char *pkey_engine_name = NULL;
293 char *pkey_identifier = NULL;
297 X509_STORE *certstore;
302 EVP_PKEY *pkey = NULL;
303 STACK_OF(X509) *chain = NULL;
307 #if defined(TLS1_2_VERSION)
308 long tls_version = TLS1_2_VERSION;
309 #elif defined(TLS1_1_VERSION)
310 long tls_version = TLS1_1_VERSION;
312 long tls_version = TLS1_VERSION;
316 * Without these can't continue
320 if (!(cacertfile[0] || capath[0]))
322 error("EAP-TLS: CA certificate file or path missing");
328 error("EAP-TLS: Certificate missing");
334 error("EAP-TLS: Private key missing");
340 SSL_load_error_strings();
342 #ifndef OPENSSL_NO_ENGINE
343 /* load the openssl config file only once and load it before triggering
344 the loading of a global openssl config file via SSL_CTX_new()
347 ssl_config = eaptls_ssl_load_config();
350 ctx = SSL_CTX_new(TLS_method());
353 error("EAP-TLS: Cannot initialize SSL CTX context");
357 #ifndef OPENSSL_NO_ENGINE
358 /* if the certificate filename is of the form engine:id. e.g.
360 then we try to load and use this engine.
361 If the certificate filename starts with a / or . then we
362 ALWAYS assume it is a file and not an engine/pkcs11 identifier
364 if ( index( certfile, '/' ) == NULL && index( certfile, '.') == NULL )
366 cert_identifier = index( certfile, ':' );
370 cert_engine_name = certfile;
371 *cert_identifier = '\0';
374 dbglog( "Found certificate engine '%s'", cert_engine_name );
375 dbglog( "Found certificate identifier '%s'", cert_identifier );
379 /* if the privatekey filename is of the form engine:id. e.g.
381 then we try to load and use this engine.
382 If the privatekey filename starts with a / or . then we
383 ALWAYS assume it is a file and not an engine/pkcs11 identifier
385 if ( index( privkeyfile, '/' ) == NULL && index( privkeyfile, '.') == NULL )
387 pkey_identifier = index( privkeyfile, ':' );
391 pkey_engine_name = privkeyfile;
392 *pkey_identifier = '\0';
395 dbglog( "Found privatekey engine '%s'", pkey_engine_name );
396 dbglog( "Found privatekey identifier '%s'", pkey_identifier );
400 if (cert_identifier && pkey_identifier)
402 if (strlen( cert_identifier ) == 0)
404 if (strlen( pkey_identifier ) == 0)
405 error( "EAP-TLS: both the certificate and privatekey identifiers are missing!" );
408 dbglog( "Substituting privatekey identifier for certificate identifier" );
409 cert_identifier = pkey_identifier;
414 if (strlen( pkey_identifier ) == 0)
416 dbglog( "Substituting certificate identifier for privatekey identifier" );
417 pkey_identifier = cert_identifier;
422 if (ssl_config && cert_engine_name)
423 cert_engine = eaptls_ssl_load_engine( cert_engine_name );
425 if (ssl_config && pkey_engine_name)
427 /* don't load the same engine twice */
428 if ( cert_engine && strcmp( cert_engine_name, pkey_engine_name) == 0 )
429 pkey_engine = cert_engine;
431 pkey_engine = eaptls_ssl_load_engine( pkey_engine_name );
435 SSL_CTX_set_default_passwd_cb (ctx, password_callback);
437 if (strlen(cacertfile) == 0) cacertfile = NULL;
438 if (strlen(capath) == 0) capath = NULL;
440 if (!SSL_CTX_load_verify_locations(ctx, cacertfile, capath))
442 error("EAP-TLS: Cannot load verify locations");
443 if (cacertfile) dbglog("CA certificate file = [%s]", cacertfile);
444 if (capath) dbglog("CA certificate path = [%s]", capath);
449 SSL_CTX_set_client_CA_list(ctx, SSL_load_client_CA_file(cacertfile));
451 #ifndef OPENSSL_NO_ENGINE
456 const char *s_slot_cert_id;
460 cert_info.s_slot_cert_id = cert_identifier;
461 cert_info.cert = NULL;
463 if (!ENGINE_ctrl_cmd( cert_engine, "LOAD_CERT_CTRL", 0, &cert_info, NULL, 0 ) )
465 error( "EAP-TLS: Error loading certificate with id '%s' from engine", cert_identifier );
471 dbglog( "Got the certificate" );
472 dbglog( "subject = %s", X509_NAME_oneline( X509_get_subject_name( cert_info.cert ), NULL, 0 ) );
473 cert = cert_info.cert;
477 warn("EAP-TLS: Cannot load PKCS11 key %s", cert_identifier);
486 input = BIO_new_file(pkcs12, "r");
489 error("EAP-TLS: Cannot open `%s' PKCS12 for input", pkcs12);
493 p12 = d2i_PKCS12_bio(input, NULL);
497 error("EAP-TLS: Cannot load PKCS12 certificate");
501 if (PKCS12_parse(p12, passwd, &pkey, &cert, &chain) != 1)
503 error("EAP-TLS: Cannot parse PKCS12 certificate, invalid password");
512 if (!SSL_CTX_use_certificate_chain_file(ctx, certfile))
514 error( "EAP-TLS: Cannot load certificate %s", certfile );
522 if (!SSL_CTX_use_certificate(ctx, cert))
524 error("EAP-TLS: Cannot use load certificate");
531 for (i = 0; i < sk_X509_num(chain); i++)
533 if (!SSL_CTX_add_extra_chain_cert(ctx, sk_X509_value(chain, i)))
535 error("EAP-TLS: Cannot add extra chain certificate");
543 * Check the Before and After dates of the certificate
546 tmp = SSL_get_certificate(ssl);
548 ret = X509_cmp_time(X509_get_notBefore(tmp), NULL);
551 warn( "EAP-TLS: Failed to read certificate notBefore field.");
555 warn( "EAP-TLS: Your certificate is not yet valid!");
558 ret = X509_cmp_time(X509_get_notAfter(tmp), NULL);
561 warn( "EAP-TLS: Failed to read certificate notAfter field.");
565 warn( "EAP-TLS: Your certificate has expired!");
569 #ifndef OPENSSL_NO_ENGINE
574 cb_data.password = passwd;
575 cb_data.prompt_info = pkey_identifier;
579 UI_METHOD* transfer_pin = UI_create_method("transfer_pin");
581 int writer (UI *ui, UI_STRING *uis)
583 PW_CB_DATA* cb_data = (PW_CB_DATA*)UI_get0_user_data(ui);
584 UI_set_result(ui, uis, cb_data->password);
587 int stub (UI* ui) {return 1;};
588 int stub_reader (UI *ui, UI_STRING *uis) {return 1;};
590 UI_method_set_writer(transfer_pin, writer);
591 UI_method_set_opener(transfer_pin, stub);
592 UI_method_set_closer(transfer_pin, stub);
593 UI_method_set_flusher(transfer_pin, stub);
594 UI_method_set_reader(transfer_pin, stub_reader);
596 dbglog( "Using our private key '%s' in engine", pkey_identifier );
597 pkey = ENGINE_load_private_key(pkey_engine, pkey_identifier, transfer_pin, &cb_data);
599 if (transfer_pin) UI_destroy_method(transfer_pin);
602 dbglog( "Loading private key '%s' from engine", pkey_identifier );
603 pkey = ENGINE_load_private_key(pkey_engine, pkey_identifier, NULL, NULL);
611 input = BIO_new_file(privkeyfile, "r");
614 error("EAP-TLS: Could not open private key, %s", privkeyfile);
618 pkey = PEM_read_bio_PrivateKey(input, NULL, password_callback, NULL);
622 error("EAP-TLS: Cannot load private key, %s", privkeyfile);
628 if (SSL_CTX_use_PrivateKey(ctx, pkey) != 1)
630 error("EAP-TLS: Cannot use private key");
634 if (SSL_CTX_check_private_key(ctx) != 1)
636 error("EAP-TLS: Private key fails security check");
640 /* Explicitly set the NO_TICKETS flag to support Win7/Win8 clients */
641 SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3
642 #ifdef SSL_OP_NO_TICKET
647 /* OpenSSL 1.1.1+ does not include RC4 ciphers by default.
648 * This causes totally obsolete WinXP clients to fail. If you really
649 * need ppp+EAP-TLS+openssl 1.1.1+WinXP then enable RC4 cipers and
650 * make sure that you use an OpenSSL that supports them
652 SSL_CTX_set_cipher_list(ctx, "RC4");
656 /* Set up a SSL Session cache with a callback. This is needed for TLSv1.3+.
657 * During the initial handshake the server signals to the client early on
658 * that the handshake is finished, even before the client has sent its
659 * credentials to the server. The actual connection (and moment that the
660 * client sends its credentials) only starts after the arrival of the first
661 * session ticket. The 'ssl_new_session_cb' catches this ticket.
663 SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_CLIENT | SSL_SESS_CACHE_NO_INTERNAL_STORE);
664 SSL_CTX_sess_set_new_cb(ctx, ssl_new_session_cb);
666 /* As EAP-TLS+TLSv1.3 is highly experimental we offer the user a chance to override */
669 if (strncmp(max_tls_version, "1.0", 3) == 0)
670 tls_version = TLS1_VERSION;
671 else if (strncmp(max_tls_version, "1.1", 3) == 0)
672 tls_version = TLS1_1_VERSION;
673 else if (strncmp(max_tls_version, "1.2", 3) == 0)
674 #ifdef TLS1_2_VERSION
675 tls_version = TLS1_2_VERSION;
678 warn("TLSv1.2 not available. Defaulting to TLSv1.1");
679 tls_version = TLS_1_1_VERSION;
682 else if (strncmp(max_tls_version, "1.3", 3) == 0)
683 #ifdef TLS1_3_VERSION
684 tls_version = TLS1_3_VERSION;
686 warn("TLSv1.3 not available.");
690 dbglog("EAP-TLS: Setting max protocol version to 0x%X", tls_version);
691 SSL_CTX_set_max_proto_version(ctx, tls_version);
693 SSL_CTX_set_verify_depth(ctx, 5);
694 SSL_CTX_set_verify(ctx,
696 SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
697 &ssl_verify_callback);
700 if (!(certstore = SSL_CTX_get_cert_store(ctx))) {
701 error("EAP-TLS: Failed to get certificate store");
706 X509_STORE_add_lookup(certstore, X509_LOOKUP_hash_dir()))) {
707 error("EAP-TLS: Store lookup for CRL failed");
712 X509_LOOKUP_add_dir(lookup, crl_dir, X509_FILETYPE_PEM);
713 X509_STORE_set_flags(certstore, X509_V_FLAG_CRL_CHECK);
718 X509_CRL *crl = NULL;
720 fp = fopen(crl_file, "r");
722 error("EAP-TLS: Cannot open CRL file '%s'", crl_file);
726 crl = PEM_read_X509_CRL(fp, NULL, NULL, NULL);
728 error("EAP-TLS: Cannot read CRL file '%s'", crl_file);
732 if (!(certstore = SSL_CTX_get_cert_store(ctx))) {
733 error("EAP-TLS: Failed to get certificate store");
736 if (!X509_STORE_add_crl(certstore, crl)) {
737 error("EAP-TLS: Cannot add CRL to certificate store");
740 X509_STORE_set_flags(certstore, X509_V_FLAG_CRL_CHECK);
745 * If a peer certificate file was specified, it must be valid, else fail
747 if (peer_certfile[0]) {
748 if (!(tmp = get_X509_from_file(peer_certfile))) {
749 error("EAP-TLS: Error loading client certificate from file %s",
767 sk_X509_pop_free(chain, X509_free);
775 * Determine the maximum packet size by looking at the LCP handshake
778 int eaptls_get_mtu(int unit)
782 lcp_options *wo = &lcp_wantoptions[unit];
783 lcp_options *go = &lcp_gotoptions[unit];
784 lcp_options *ho = &lcp_hisoptions[unit];
785 lcp_options *ao = &lcp_allowoptions[unit];
787 mtu = ho->neg_mru? ho->mru: PPP_MRU;
788 mru = go->neg_mru? MAX(wo->mru, go->mru): PPP_MRU;
789 mtu = MIN(MIN(mtu, mru), ao->mru)- PPP_HDRLEN - 10;
791 dbglog("MTU = %d", mtu);
797 * Init the ssl handshake (server mode)
799 int eaptls_init_ssl_server(eap_state * esp)
801 struct eaptls_session *ets;
802 char servcertfile[MAXWORDLEN];
803 char clicertfile[MAXWORDLEN];
804 char cacertfile[MAXWORDLEN];
805 char capath[MAXWORDLEN];
806 char pkfile[MAXWORDLEN];
807 char pkcs12[MAXWORDLEN];
810 * Allocate new eaptls session
812 esp->es_server.ea_session = malloc(sizeof(struct eaptls_session));
813 if (!esp->es_server.ea_session)
814 fatal("Allocation error");
815 ets = esp->es_server.ea_session;
818 if (!esp->es_server.ea_peer) {
819 error("EAP-TLS: Error: client name not set (BUG)");
823 strlcpy(ets->peer, esp->es_server.ea_peer, MAXWORDLEN-1);
825 dbglog( "getting eaptls secret" );
826 if (!get_eaptls_secret(esp->es_unit, esp->es_server.ea_peer,
827 esp->es_server.ea_name, clicertfile,
828 servcertfile, cacertfile, capath, pkfile, pkcs12, 1)) {
829 error( "EAP-TLS: Cannot get secret/password for client \"%s\", server \"%s\"",
830 esp->es_server.ea_peer, esp->es_server.ea_name );
834 ets->mtu = eaptls_get_mtu(esp->es_unit);
836 ets->ctx = eaptls_init_ssl(1, cacertfile, capath, servcertfile, clicertfile, pkfile, pkcs12);
840 if (!(ets->ssl = SSL_new(ets->ctx)))
844 * Set auto-retry to avoid timeouts on BIO_read
846 SSL_set_mode(ets->ssl, SSL_MODE_AUTO_RETRY);
849 * Initialize the BIOs we use to read/write to ssl engine
851 ets->into_ssl = BIO_new(BIO_s_mem());
852 ets->from_ssl = BIO_new(BIO_s_mem());
853 SSL_set_bio(ets->ssl, ets->into_ssl, ets->from_ssl);
855 SSL_set_msg_callback(ets->ssl, ssl_msg_callback);
856 SSL_set_msg_callback_arg(ets->ssl, ets);
859 * Attach the session struct to the connection, so we can later
860 * retrieve it when doing certificate verification
862 SSL_set_ex_data(ets->ssl, 0, ets);
864 SSL_set_accept_state(ets->ssl);
874 * If we specified the client certificate file, store it in ets->peercertfile,
875 * so we can check it later in ssl_verify_callback()
878 strlcpy(&ets->peercertfile[0], clicertfile, MAXWORDLEN);
880 ets->peercertfile[0] = 0;
885 SSL_CTX_free(ets->ctx);
890 * Init the ssl handshake (client mode)
892 int eaptls_init_ssl_client(eap_state * esp)
894 struct eaptls_session *ets;
895 char servcertfile[MAXWORDLEN];
896 char clicertfile[MAXWORDLEN];
897 char cacertfile[MAXWORDLEN];
898 char capath[MAXWORDLEN];
899 char pkfile[MAXWORDLEN];
900 char pkcs12[MAXWORDLEN];
903 * Allocate new eaptls session
905 esp->es_client.ea_session = malloc(sizeof(struct eaptls_session));
906 if (!esp->es_client.ea_session)
907 fatal("Allocation error");
908 ets = esp->es_client.ea_session;
912 * If available, copy server name in ets; it will be used in cert
915 if (esp->es_client.ea_peer)
916 strlcpy(ets->peer, esp->es_client.ea_peer, MAXWORDLEN-1);
920 ets->mtu = eaptls_get_mtu(esp->es_unit);
922 dbglog( "calling get_eaptls_secret" );
923 if (!get_eaptls_secret(esp->es_unit, esp->es_client.ea_name,
924 ets->peer, clicertfile,
925 servcertfile, cacertfile, capath, pkfile, pkcs12, 0)) {
926 error( "EAP-TLS: Cannot get secret/password for client \"%s\", server \"%s\"",
927 esp->es_client.ea_name, ets->peer );
931 dbglog( "calling eaptls_init_ssl" );
932 ets->ctx = eaptls_init_ssl(0, cacertfile, capath, clicertfile, servcertfile, pkfile, pkcs12);
936 ets->ssl = SSL_new(ets->ctx);
942 * Initialize the BIOs we use to read/write to ssl engine
944 dbglog( "Initializing SSL BIOs" );
945 ets->into_ssl = BIO_new(BIO_s_mem());
946 ets->from_ssl = BIO_new(BIO_s_mem());
947 SSL_set_bio(ets->ssl, ets->into_ssl, ets->from_ssl);
949 SSL_set_msg_callback(ets->ssl, ssl_msg_callback);
950 SSL_set_msg_callback_arg(ets->ssl, ets);
953 * Attach the session struct to the connection, so we can later
954 * retrieve it when doing certificate verification
956 SSL_set_ex_data(ets->ssl, 0, ets);
958 SSL_set_connect_state(ets->ssl);
968 * If we specified the server certificate file, store it in
969 * ets->peercertfile, so we can check it later in
970 * ssl_verify_callback()
973 strlcpy(ets->peercertfile, servcertfile, MAXWORDLEN);
975 ets->peercertfile[0] = 0;
980 dbglog( "eaptls_init_ssl_client: fail" );
981 SSL_CTX_free(ets->ctx);
986 void eaptls_free_session(struct eaptls_session *ets)
992 SSL_CTX_free(ets->ctx);
998 int eaptls_is_init_finished(struct eaptls_session *ets)
1000 if (ets->ssl && SSL_is_init_finished(ets->ssl))
1003 return have_session_ticket;
1012 * Handle a received packet, reassembling fragmented messages and
1013 * passing them to the ssl engine
1015 int eaptls_receive(struct eaptls_session *ets, u_char * inp, int len)
1019 u_char dummy[65536];
1022 warn("EAP-TLS: received no or invalid data");
1026 GETCHAR(flags, inp);
1029 if (flags & EAP_TLS_FLAGS_LI && len > 4) {
1031 * LenghtIncluded flag set -> this is the first packet of a message
1035 * the first 4 octets are the length of the EAP-TLS message
1037 GETLONG(tlslen, inp);
1042 if (tlslen > EAP_TLS_MAX_LEN) {
1043 error("EAP-TLS: TLS message length > %d, truncated", EAP_TLS_MAX_LEN);
1044 tlslen = EAP_TLS_MAX_LEN;
1048 * Allocate memory for the whole message
1050 ets->data = malloc(tlslen);
1052 fatal("EAP-TLS: allocation error\n");
1055 ets->tlslen = tlslen;
1058 warn("EAP-TLS: non-first LI packet? that's odd...");
1060 else if (!ets->data) {
1062 * A non fragmented message without LI flag
1065 ets->data = malloc(len);
1067 fatal("EAP-TLS: memory allocation error in eaptls_receive\n");
1073 if (flags & EAP_TLS_FLAGS_MF)
1079 warn("EAP-TLS: received malformed data");
1083 if (len + ets->datalen > ets->tlslen) {
1084 warn("EAP-TLS: received data > TLS message length");
1088 BCOPY(inp, ets->data + ets->datalen, len);
1089 ets->datalen += len;
1094 * If we have the whole message, pass it to ssl
1097 if (ets->datalen != ets->tlslen) {
1098 warn("EAP-TLS: received data != TLS message length");
1102 if (BIO_write(ets->into_ssl, ets->data, ets->datalen) == -1)
1105 SSL_read(ets->ssl, dummy, 65536);
1116 * Return an eap-tls packet in outp.
1117 * A TLS message read from the ssl engine is buffered in ets->data.
1118 * At each call we control if there is buffered data and send a
1119 * packet of mtu bytes.
1121 int eaptls_send(struct eaptls_session *ets, u_char ** outp)
1125 u_char fromtls[65536];
1133 if(!ets->alert_sent)
1135 res = SSL_read(ets->ssl, fromtls, 65536);
1141 if ((res = BIO_read(ets->from_ssl, fromtls, 65536)) == -1)
1143 warn("EAP-TLS send: No data from BIO_read");
1149 ets->data = malloc(ets->datalen);
1151 fatal("EAP-TLS: memory allocation error in eaptls_send\n");
1153 BCOPY(fromtls, ets->data, ets->datalen);
1159 size = ets->datalen - ets->offset;
1161 if (size > ets->mtu) {
1167 PUTCHAR(EAPT_TLS, *outp);
1170 * Set right flags and length if necessary
1172 if (ets->frag && first) {
1173 PUTCHAR(EAP_TLS_FLAGS_LI | EAP_TLS_FLAGS_MF, *outp);
1174 PUTLONG(ets->datalen, *outp);
1175 } else if (ets->frag) {
1176 PUTCHAR(EAP_TLS_FLAGS_MF, *outp);
1181 * Copy the data in outp
1183 BCOPY(ets->data + ets->offset, *outp, size);
1184 INCPTR(size, *outp);
1187 * Copy the packet in retransmission buffer
1189 BCOPY(start, &ets->rtx[0], *outp - start);
1190 ets->rtx_len = *outp - start;
1192 ets->offset += size;
1194 if (ets->offset >= ets->datalen) {
1197 * The whole message has been sent
1210 * Get the sent packet from the retransmission buffer
1212 void eaptls_retransmit(struct eaptls_session *ets, u_char ** outp)
1214 BCOPY(ets->rtx, *outp, ets->rtx_len);
1215 INCPTR(ets->rtx_len, *outp);
1219 * Verify a certificate.
1220 * Most of the work (signatures and issuer attributes checking)
1221 * is done by ssl; we check the CN in the peer certificate
1222 * against the peer name.
1224 int ssl_verify_callback(int ok, X509_STORE_CTX * ctx)
1231 struct eaptls_session *ets;
1232 char *ptr1 = NULL, *ptr2 = NULL;
1234 peer_cert = X509_STORE_CTX_get_current_cert(ctx);
1235 err = X509_STORE_CTX_get_error(ctx);
1236 depth = X509_STORE_CTX_get_error_depth(ctx);
1238 dbglog("certificate verify depth: %d", depth);
1240 if (auth_required && !ok) {
1241 X509_NAME_oneline(X509_get_subject_name(peer_cert),
1244 X509_NAME_get_text_by_NID(X509_get_subject_name(peer_cert),
1245 NID_commonName, cn_str, 256);
1247 dbglog("Certificate verification error:\n depth: %d CN: %s"
1248 "\n err: %d (%s)\n", depth, cn_str, err,
1249 X509_verify_cert_error_string(err));
1254 ssl = X509_STORE_CTX_get_ex_data(ctx,
1255 SSL_get_ex_data_X509_STORE_CTX_idx());
1257 ets = (struct eaptls_session *)SSL_get_ex_data(ssl, 0);
1260 error("Error: SSL_get_ex_data returned NULL");
1268 /* Verify certificate based on certificate type and extended key usage */
1269 if (tls_verify_key_usage) {
1270 int purpose = ets->client ? X509_PURPOSE_SSL_SERVER : X509_PURPOSE_SSL_CLIENT ;
1271 if (X509_check_purpose(peer_cert, purpose, 0) == 0) {
1272 error("Certificate verification error: nsCertType mismatch");
1276 #if OPENSSL_VERSION_NUMBER >= 0x10100000L
1277 int flags = ets->client ? XKU_SSL_SERVER : XKU_SSL_CLIENT;
1278 if (!(X509_get_extended_key_usage(peer_cert) & flags)) {
1279 error("Certificate verification error: invalid extended key usage");
1283 info("Certificate key usage: OK");
1287 * If acting as client and the name of the server wasn't specified
1288 * explicitely, we can't verify the server authenticity
1290 if (!tls_verify_method)
1291 tls_verify_method = TLS_VERIFY_NONE;
1293 if (!ets->peer[0] || !strcmp(TLS_VERIFY_NONE, tls_verify_method)) {
1294 warn("Certificate verication disabled or no peer name was specified");
1298 /* This is the peer certificate */
1299 X509_NAME_oneline(X509_get_subject_name(peer_cert),
1302 X509_NAME_get_text_by_NID(X509_get_subject_name(peer_cert),
1303 NID_commonName, cn_str, 256);
1305 /* Verify based on subject name */
1307 if (!strcmp(TLS_VERIFY_SUBJECT, tls_verify_method)) {
1311 /* Verify based on common name (default) */
1312 if (strlen(tls_verify_method) == 0 ||
1313 !strcmp(TLS_VERIFY_NAME, tls_verify_method)) {
1317 /* Match the suffix of common name */
1318 if (!strcmp(TLS_VERIFY_SUFFIX, tls_verify_method)) {
1319 int len = strlen(ptr1);
1320 int off = strlen(cn_str) - len;
1323 ptr2 = cn_str + off;
1327 if (strcmp(ptr1, ptr2)) {
1328 error("Certificate verification error: CN (%s) != %s", ptr1, ptr2);
1332 info("Certificate CN: %s, peer name %s", cn_str, ets->peer);
1335 * If a peer certificate file was specified, here we check it
1337 if (ets->peercertfile[0]) {
1338 if (ssl_cmp_certs(&ets->peercertfile[0], peer_cert)
1341 ("Peer certificate doesn't match stored certificate");
1351 * Compare a certificate with the one stored in a file
1353 int ssl_cmp_certs(char *filename, X509 * a)
1358 if (!(b = get_X509_from_file(filename)))
1361 ret = X509_cmp(a, b);
1368 X509 *get_X509_from_file(char *filename)
1373 if (!(fp = fopen(filename, "r")))
1376 ret = PEM_read_X509(fp, NULL, NULL, NULL);
1384 * Every sent & received message this callback function is invoked,
1385 * so we know when alert messages have arrived or are sent and
1386 * we can print debug information about TLS handshake.
1389 ssl_msg_callback(int write_p, int version, int content_type,
1390 const void *buf, size_t len, SSL * ssl, void *arg)
1393 struct eaptls_session *ets = (struct eaptls_session *)arg;
1395 const unsigned char*msg = buf;
1396 int hvers = msg[1] << 8 | msg[2];
1399 strcpy(string, " -> ");
1401 strcpy(string, " <- ");
1403 switch(content_type) {
1405 case SSL3_RT_HEADER:
1406 strcat(string, "SSL/TLS Header: ");
1409 strcat(string, "SSL 3.0");
1412 strcat(string, "TLS 1.0");
1414 case TLS1_1_VERSION:
1415 strcat(string, "TLS 1.1");
1417 case TLS1_2_VERSION:
1418 strcat(string, "TLS 1.2");
1421 sprintf(string, "SSL/TLS Header: Unknown version (%d)", hvers);
1426 strcat(string, "Alert: ");
1430 ets->alert_sent = 1;
1431 ets->alert_sent_desc = code;
1433 ets->alert_recv = 1;
1434 ets->alert_recv_desc = code;
1437 strcat(string, SSL_alert_desc_string_long(code));
1440 case SSL3_RT_CHANGE_CIPHER_SPEC:
1441 strcat(string, "ChangeCipherSpec");
1444 #ifdef SSL3_RT_INNER_CONTENT_TYPE
1445 case SSL3_RT_INNER_CONTENT_TYPE:
1446 strcat(string, "InnerContentType (TLS1.3)");
1450 case SSL3_RT_HANDSHAKE:
1452 strcat(string, "Handshake: ");
1456 case SSL3_MT_HELLO_REQUEST:
1457 strcat(string,"Hello Request");
1459 case SSL3_MT_CLIENT_HELLO:
1460 strcat(string,"Client Hello");
1462 case SSL3_MT_SERVER_HELLO:
1463 strcat(string,"Server Hello");
1465 #ifdef SSL3_MT_NEWSESSION_TICKET
1466 case SSL3_MT_NEWSESSION_TICKET:
1467 strcat(string,"New Session Ticket");
1470 #ifdef SSL3_MT_END_OF_EARLY_DATA
1471 case SSL3_MT_END_OF_EARLY_DATA:
1472 strcat(string,"End of Early Data");
1475 #ifdef SSL3_MT_ENCRYPTED_EXTENSIONS
1476 case SSL3_MT_ENCRYPTED_EXTENSIONS:
1477 strcat(string,"Encryped Extensions");
1480 case SSL3_MT_CERTIFICATE:
1481 strcat(string,"Certificate");
1483 case SSL3_MT_SERVER_KEY_EXCHANGE:
1484 strcat(string,"Server Key Exchange");
1486 case SSL3_MT_CERTIFICATE_REQUEST:
1487 strcat(string,"Certificate Request");
1489 case SSL3_MT_SERVER_DONE:
1490 strcat(string,"Server Hello Done");
1492 case SSL3_MT_CERTIFICATE_VERIFY:
1493 strcat(string,"Certificate Verify");
1495 case SSL3_MT_CLIENT_KEY_EXCHANGE:
1496 strcat(string,"Client Key Exchange");
1498 case SSL3_MT_FINISHED:
1499 strcat(string,"Finished: ");
1500 hvers = SSL_version(ssl);
1503 strcat(string, "SSL 3.0");
1506 strcat(string, "TLS 1.0");
1508 case TLS1_1_VERSION:
1509 strcat(string, "TLS 1.1");
1511 case TLS1_2_VERSION:
1512 strcat(string, "TLS 1.2");
1514 #ifdef TLS1_3_VERSION
1515 case TLS1_3_VERSION:
1516 strcat(string, "TLS 1.3 (experimental)");
1521 strcat(string, "Unknown version");
1525 sprintf( string, "Handshake: Unknown SSL3 code received: %d", code );
1530 sprintf( string, "SSL message contains unknown content type: %d", content_type );
1533 /* Alert messages must always be displayed */
1534 if(content_type == SSL3_RT_ALERT)
1535 error("%s", string);
1537 dbglog("%s", string);
1541 ssl_new_session_cb(SSL *s, SSL_SESSION *sess)
1543 dbglog("EAP-TLS: Post-Handshake New Session Ticket arrived:");
1544 have_session_ticket = 1;
1546 /* always return success */