1/* tls_g.c - Handle tls/ssl using GNUTLS. */
2/* $OpenLDAP$ */
3/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
4 *
5 * Copyright 2008-2011 The OpenLDAP Foundation.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted only as authorized by the OpenLDAP
10 * Public License.
11 *
12 * A copy of this license is available in the file LICENSE in the
13 * top-level directory of the distribution or, alternatively, at
14 * <http://www.OpenLDAP.org/license.html>.
15 */
16/* ACKNOWLEDGEMENTS: GNUTLS support written by Howard Chu and
17 * Matt Backes; sponsored by The Written Word (thewrittenword.com)
18 * and Stanford University (stanford.edu).
19 */
20
21#include "portable.h"
22
23#ifdef HAVE_GNUTLS
24
25#include "ldap_config.h"
26
27#include <stdio.h>
28
29#include <ac/stdlib.h>
30#include <ac/errno.h>
31#include <ac/socket.h>
32#include <ac/string.h>
33#include <ac/ctype.h>
34#include <ac/time.h>
35#include <ac/unistd.h>
36#include <ac/param.h>
37#include <ac/dirent.h>
38#include <sys/stat.h>
39#include <fcntl.h>
40
41#include "ldap-int.h"
42#include "ldap-tls.h"
43
44#include <gnutls/gnutls.h>
45#include <gnutls/x509.h>
46#include <gcrypt.h>
47
48#define DH_BITS	(1024)
49
50#if LIBGNUTLS_VERSION_NUMBER >= 0x020200
51#define	HAVE_CIPHERSUITES	1
52/* This is a kludge. gcrypt 1.4.x has support. Recent GnuTLS requires gcrypt 1.4.x
53 * but that dependency isn't reflected in their configure script, resulting in
54 * build errors on older gcrypt. So, if they have a working build environment,
55 * assume gcrypt is new enough.
56 */
57#define HAVE_GCRYPT_RAND	1
58#else
59#undef HAVE_CIPHERSUITES
60#undef HAVE_GCRYPT_RAND
61#endif
62
63#ifndef HAVE_CIPHERSUITES
64/* Versions prior to 2.2.0 didn't handle cipher suites, so we had to
65 * kludge them ourselves.
66 */
67typedef struct tls_cipher_suite {
68	const char *name;
69	gnutls_kx_algorithm_t kx;
70	gnutls_cipher_algorithm_t cipher;
71	gnutls_mac_algorithm_t mac;
72	gnutls_protocol_t version;
73} tls_cipher_suite;
74#endif
75
76typedef struct tlsg_ctx {
77	struct ldapoptions *lo;
78	gnutls_certificate_credentials_t cred;
79	gnutls_dh_params_t dh_params;
80	unsigned long verify_depth;
81	int refcount;
82#ifdef HAVE_CIPHERSUITES
83	gnutls_priority_t prios;
84#else
85	int *kx_list;
86	int *cipher_list;
87	int *mac_list;
88#endif
89#ifdef LDAP_R_COMPILE
90	ldap_pvt_thread_mutex_t ref_mutex;
91#endif
92} tlsg_ctx;
93
94typedef struct tlsg_session {
95	gnutls_session_t session;
96	tlsg_ctx *ctx;
97	struct berval peer_der_dn;
98} tlsg_session;
99
100#ifndef HAVE_CIPHERSUITES
101static tls_cipher_suite *tlsg_ciphers;
102static int tlsg_n_ciphers;
103#endif
104
105static int tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites );
106static int tlsg_cert_verify( tlsg_session *s );
107
108#ifdef LDAP_R_COMPILE
109
110static int
111tlsg_mutex_init( void **priv )
112{
113	int err = 0;
114	ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t ));
115
116	if ( !lock )
117		err = ENOMEM;
118	if ( !err ) {
119		err = ldap_pvt_thread_mutex_init( lock );
120		if ( err )
121			LDAP_FREE( lock );
122		else
123			*priv = lock;
124	}
125	return err;
126}
127
128static int
129tlsg_mutex_destroy( void **lock )
130{
131	int err = ldap_pvt_thread_mutex_destroy( *lock );
132	LDAP_FREE( *lock );
133	return err;
134}
135
136static int
137tlsg_mutex_lock( void **lock )
138{
139	return ldap_pvt_thread_mutex_lock( *lock );
140}
141
142static int
143tlsg_mutex_unlock( void **lock )
144{
145	return ldap_pvt_thread_mutex_unlock( *lock );
146}
147
148static struct gcry_thread_cbs tlsg_thread_cbs = {
149	GCRY_THREAD_OPTION_USER,
150	NULL,
151	tlsg_mutex_init,
152	tlsg_mutex_destroy,
153	tlsg_mutex_lock,
154	tlsg_mutex_unlock,
155	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
156};
157
158static void
159tlsg_thr_init( void )
160{
161	gcry_control (GCRYCTL_SET_THREAD_CBS, &tlsg_thread_cbs);
162}
163#endif /* LDAP_R_COMPILE */
164
165/*
166 * Initialize TLS subsystem. Should be called only once.
167 */
168static int
169tlsg_init( void )
170{
171#ifdef HAVE_GCRYPT_RAND
172	struct ldapoptions *lo = LDAP_INT_GLOBAL_OPT();
173	if ( lo->ldo_tls_randfile &&
174		gcry_control( GCRYCTL_SET_RNDEGD_SOCKET, lo->ldo_tls_randfile )) {
175		Debug( LDAP_DEBUG_ANY,
176		"TLS: gcry_control GCRYCTL_SET_RNDEGD_SOCKET failed\n",
177		0, 0, 0);
178		return -1;
179	}
180#endif
181
182	gnutls_global_init();
183
184#ifndef HAVE_CIPHERSUITES
185	/* GNUtls cipher suite handling: The library ought to parse suite
186	 * names for us, but it doesn't. It will return a list of suite names
187	 * that it supports, so we can do parsing ourselves. It ought to tell
188	 * us how long the list is, but it doesn't do that either, so we just
189	 * have to count it manually...
190	 */
191	{
192		int i = 0;
193		tls_cipher_suite *ptr, tmp;
194		char cs_id[2];
195
196		while ( gnutls_cipher_suite_info( i, cs_id, &tmp.kx, &tmp.cipher,
197			&tmp.mac, &tmp.version ))
198			i++;
199		tlsg_n_ciphers = i;
200
201		/* Store a copy */
202		tlsg_ciphers = LDAP_MALLOC(tlsg_n_ciphers * sizeof(tls_cipher_suite));
203		if ( !tlsg_ciphers )
204			return -1;
205		for ( i=0; i<tlsg_n_ciphers; i++ ) {
206			tlsg_ciphers[i].name = gnutls_cipher_suite_info( i, cs_id,
207				&tlsg_ciphers[i].kx, &tlsg_ciphers[i].cipher, &tlsg_ciphers[i].mac,
208				&tlsg_ciphers[i].version );
209		}
210	}
211#endif
212	return 0;
213}
214
215/*
216 * Tear down the TLS subsystem. Should only be called once.
217 */
218static void
219tlsg_destroy( void )
220{
221#ifndef HAVE_CIPHERSUITES
222	LDAP_FREE( tlsg_ciphers );
223	tlsg_ciphers = NULL;
224	tlsg_n_ciphers = 0;
225#endif
226	gnutls_global_deinit();
227}
228
229static tls_ctx *
230tlsg_ctx_new ( struct ldapoptions *lo )
231{
232	tlsg_ctx *ctx;
233
234	ctx = ber_memcalloc ( 1, sizeof (*ctx) );
235	if ( ctx ) {
236		ctx->lo = lo;
237		if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
238			ber_memfree( ctx );
239			return NULL;
240		}
241		ctx->refcount = 1;
242#ifdef HAVE_CIPHERSUITES
243		gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
244#endif
245#ifdef LDAP_R_COMPILE
246		ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
247#endif
248	}
249	return (tls_ctx *)ctx;
250}
251
252static void
253tlsg_ctx_ref( tls_ctx *ctx )
254{
255	tlsg_ctx *c = (tlsg_ctx *)ctx;
256	LDAP_MUTEX_LOCK( &c->ref_mutex );
257	c->refcount++;
258	LDAP_MUTEX_UNLOCK( &c->ref_mutex );
259}
260
261static void
262tlsg_ctx_free ( tls_ctx *ctx )
263{
264	tlsg_ctx *c = (tlsg_ctx *)ctx;
265	int refcount;
266
267	if ( !c ) return;
268
269	LDAP_MUTEX_LOCK( &c->ref_mutex );
270	refcount = --c->refcount;
271	LDAP_MUTEX_UNLOCK( &c->ref_mutex );
272	if ( refcount )
273		return;
274#ifdef HAVE_CIPHERSUITES
275	gnutls_priority_deinit( c->prios );
276#else
277	LDAP_FREE( c->kx_list );
278#endif
279	gnutls_certificate_free_credentials( c->cred );
280	ber_memfree ( c );
281}
282
283static int
284tlsg_getfile( const char *path, gnutls_datum_t *buf )
285{
286	int rc = -1, fd;
287	struct stat st;
288
289	fd = open( path, O_RDONLY );
290	if ( fd >= 0 && fstat( fd, &st ) == 0 ) {
291		buf->size = st.st_size;
292		buf->data = LDAP_MALLOC( st.st_size + 1 );
293		if ( buf->data ) {
294			rc = read( fd, buf->data, st.st_size );
295			close( fd );
296			if ( rc < st.st_size )
297				rc = -1;
298			else
299				rc = 0;
300		}
301	}
302	return rc;
303}
304
305/* This is the GnuTLS default */
306#define	VERIFY_DEPTH	6
307
308/*
309 * initialize a new TLS context
310 */
311static int
312tlsg_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
313{
314	tlsg_ctx *ctx = lo->ldo_tls_ctx;
315	int rc;
316
317 	if ( lo->ldo_tls_ciphersuite &&
318		tlsg_parse_ciphers( ctx, lt->lt_ciphersuite )) {
319 		Debug( LDAP_DEBUG_ANY,
320 			   "TLS: could not set cipher list %s.\n",
321 			   lo->ldo_tls_ciphersuite, 0, 0 );
322		return -1;
323 	}
324
325	if (lo->ldo_tls_cacertdir != NULL) {
326		Debug( LDAP_DEBUG_ANY,
327		       "TLS: warning: cacertdir not implemented for gnutls\n",
328		       NULL, NULL, NULL );
329	}
330
331	if (lo->ldo_tls_cacertfile != NULL) {
332		rc = gnutls_certificate_set_x509_trust_file(
333			ctx->cred,
334			lt->lt_cacertfile,
335			GNUTLS_X509_FMT_PEM );
336		if ( rc < 0 ) return -1;
337	}
338
339	if ( lo->ldo_tls_certfile && lo->ldo_tls_keyfile ) {
340		gnutls_x509_privkey_t key;
341		gnutls_datum_t buf;
342		gnutls_x509_crt_t certs[VERIFY_DEPTH];
343		unsigned int max = VERIFY_DEPTH;
344
345		rc = gnutls_x509_privkey_init( &key );
346		if ( rc ) return -1;
347
348		/* OpenSSL builds the cert chain for us, but GnuTLS
349		 * expects it to be present in the certfile. If it's
350		 * not, we have to build it ourselves. So we have to
351		 * do some special checks here...
352		 */
353		rc = tlsg_getfile( lt->lt_keyfile, &buf );
354		if ( rc ) return -1;
355		rc = gnutls_x509_privkey_import( key, &buf,
356			GNUTLS_X509_FMT_PEM );
357		LDAP_FREE( buf.data );
358		if ( rc < 0 ) return rc;
359
360		rc = tlsg_getfile( lt->lt_certfile, &buf );
361		if ( rc ) return -1;
362		rc = gnutls_x509_crt_list_import( certs, &max, &buf,
363			GNUTLS_X509_FMT_PEM, 0 );
364		LDAP_FREE( buf.data );
365		if ( rc < 0 ) return rc;
366
367		/* If there's only one cert and it's not self-signed,
368		 * then we have to build the cert chain.
369		 */
370		if ( max == 1 && !gnutls_x509_crt_check_issuer( certs[0], certs[0] )) {
371			gnutls_x509_crt_t *cas;
372			unsigned int i, j, ncas;
373
374			gnutls_certificate_get_x509_cas( ctx->cred, &cas, &ncas );
375			for ( i = 1; i<VERIFY_DEPTH; i++ ) {
376				for ( j = 0; j<ncas; j++ ) {
377					if ( gnutls_x509_crt_check_issuer( certs[i-1], cas[j] )) {
378						certs[i] = cas[j];
379						max++;
380						/* If this CA is self-signed, we're done */
381						if ( gnutls_x509_crt_check_issuer( cas[j], cas[j] ))
382							j = ncas;
383						break;
384					}
385				}
386				/* only continue if we found a CA and it was not self-signed */
387				if ( j == ncas )
388					break;
389			}
390		}
391		rc = gnutls_certificate_set_x509_key( ctx->cred, certs, max, key );
392		if ( rc ) return -1;
393	} else if ( lo->ldo_tls_certfile || lo->ldo_tls_keyfile ) {
394		Debug( LDAP_DEBUG_ANY,
395		       "TLS: only one of certfile and keyfile specified\n",
396		       NULL, NULL, NULL );
397		return -1;
398	}
399
400	if ( lo->ldo_tls_dhfile ) {
401		Debug( LDAP_DEBUG_ANY,
402		       "TLS: warning: ignoring dhfile\n",
403		       NULL, NULL, NULL );
404	}
405
406	if ( lo->ldo_tls_crlfile ) {
407		rc = gnutls_certificate_set_x509_crl_file(
408			ctx->cred,
409			lt->lt_crlfile,
410			GNUTLS_X509_FMT_PEM );
411		if ( rc < 0 ) return -1;
412		rc = 0;
413	}
414
415	/* FIXME: ITS#5992 - this should go be configurable,
416	 * and V1 CA certs should be phased out ASAP.
417	 */
418	gnutls_certificate_set_verify_flags( ctx->cred,
419		GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
420
421	if ( is_server ) {
422		gnutls_dh_params_init(&ctx->dh_params);
423		gnutls_dh_params_generate2(ctx->dh_params, DH_BITS);
424	}
425	return 0;
426}
427
428static tls_session *
429tlsg_session_new ( tls_ctx * ctx, int is_server )
430{
431	tlsg_ctx *c = (tlsg_ctx *)ctx;
432	tlsg_session *session;
433
434	session = ber_memcalloc ( 1, sizeof (*session) );
435	if ( !session )
436		return NULL;
437
438	session->ctx = c;
439	gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
440#ifdef HAVE_CIPHERSUITES
441	gnutls_priority_set( session->session, c->prios );
442#else
443	gnutls_set_default_priority( session->session );
444	if ( c->kx_list ) {
445		gnutls_kx_set_priority( session->session, c->kx_list );
446		gnutls_cipher_set_priority( session->session, c->cipher_list );
447		gnutls_mac_set_priority( session->session, c->mac_list );
448	}
449#endif
450	if ( c->cred )
451		gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
452
453	if ( is_server ) {
454		int flag = 0;
455		if ( c->lo->ldo_tls_require_cert ) {
456			flag = GNUTLS_CERT_REQUEST;
457			if ( c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
458				c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD )
459				flag = GNUTLS_CERT_REQUIRE;
460			gnutls_certificate_server_set_request( session->session, flag );
461		}
462	}
463	return (tls_session *)session;
464}
465
466static int
467tlsg_session_accept( tls_session *session )
468{
469	tlsg_session *s = (tlsg_session *)session;
470	int rc;
471
472	rc = gnutls_handshake( s->session );
473	if ( rc == 0 && s->ctx->lo->ldo_tls_require_cert != LDAP_OPT_X_TLS_NEVER ) {
474		const gnutls_datum_t *peer_cert_list;
475		unsigned int list_size;
476
477		peer_cert_list = gnutls_certificate_get_peers( s->session,
478						&list_size );
479		if ( !peer_cert_list && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_TRY )
480			rc = 0;
481		else {
482			rc = tlsg_cert_verify( s );
483			if ( rc && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW )
484				rc = 0;
485		}
486	}
487	return rc;
488}
489
490static int
491tlsg_session_connect( LDAP *ld, tls_session *session )
492{
493	return tlsg_session_accept( session);
494}
495
496static int
497tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
498{
499	tlsg_session *s = (tlsg_session *)session;
500
501	if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
502		return 0;
503
504	switch (gnutls_record_get_direction (s->session)) {
505	case 0:
506		sb->sb_trans_needs_read = 1;
507		return 1;
508	case 1:
509		sb->sb_trans_needs_write = 1;
510		return 1;
511	}
512	return 0;
513}
514
515static char *
516tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
517{
518	return (char *)gnutls_strerror( rc );
519}
520
521static void
522tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
523{
524	BerElementBuffer berbuf;
525	BerElement *ber = (BerElement *)&berbuf;
526	ber_tag_t tag;
527	ber_len_t len;
528	ber_int_t i;
529
530	ber_init2( ber, cert, LBER_USE_DER );
531	tag = ber_skip_tag( ber, &len );	/* Sequence */
532	tag = ber_skip_tag( ber, &len );	/* Sequence */
533	tag = ber_peek_tag( ber, &len );	/* Context + Constructed (version) */
534	if ( tag == 0xa0 ) {	/* Version is optional */
535		tag = ber_skip_tag( ber, &len );
536		tag = ber_get_int( ber, &i );	/* Int: Version */
537	}
538	tag = ber_skip_tag( ber, &len );	/* Int: Serial (can be longer than ber_int_t) */
539	ber_skip_data( ber, len );
540	tag = ber_skip_tag( ber, &len );	/* Sequence: Signature */
541	ber_skip_data( ber, len );
542	if ( !get_subject ) {
543		tag = ber_peek_tag( ber, &len );	/* Sequence: Issuer DN */
544	} else {
545		tag = ber_skip_tag( ber, &len );
546		ber_skip_data( ber, len );
547		tag = ber_skip_tag( ber, &len );	/* Sequence: Validity */
548		ber_skip_data( ber, len );
549		tag = ber_peek_tag( ber, &len );	/* Sequence: Subject DN */
550	}
551	len = ber_ptrlen( ber );
552	dn->bv_val = cert->bv_val + len;
553	dn->bv_len = cert->bv_len - len;
554}
555
556static int
557tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
558{
559	tlsg_session *s = (tlsg_session *)session;
560	const gnutls_datum_t *x;
561	struct berval bv;
562
563	x = gnutls_certificate_get_ours( s->session );
564
565	if (!x) return LDAP_INVALID_CREDENTIALS;
566
567	bv.bv_val = (char *) x->data;
568	bv.bv_len = x->size;
569
570	tlsg_x509_cert_dn( &bv, der_dn, 1 );
571	return 0;
572}
573
574static int
575tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
576{
577	tlsg_session *s = (tlsg_session *)session;
578	if ( !s->peer_der_dn.bv_val ) {
579		const gnutls_datum_t *peer_cert_list;
580		unsigned int list_size;
581		struct berval bv;
582
583		peer_cert_list = gnutls_certificate_get_peers( s->session,
584							&list_size );
585		if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
586
587		bv.bv_len = peer_cert_list->size;
588		bv.bv_val = (char *) peer_cert_list->data;
589
590		tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
591	}
592	*der_dn = s->peer_der_dn;
593	return 0;
594}
595
596/* what kind of hostname were we given? */
597#define	IS_DNS	0
598#define	IS_IP4	1
599#define	IS_IP6	2
600
601#define	CN_OID	"2.5.4.3"
602
603static int
604tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
605{
606	tlsg_session *s = (tlsg_session *)session;
607	int i, ret;
608	const gnutls_datum_t *peer_cert_list;
609	unsigned int list_size;
610	char altname[NI_MAXHOST];
611	size_t altnamesize;
612
613	gnutls_x509_crt_t cert;
614	const char *name;
615	char *ptr;
616	char *domain = NULL;
617#ifdef LDAP_PF_INET6
618	struct in6_addr addr;
619#else
620	struct in_addr addr;
621#endif
622	int len1 = 0, len2 = 0;
623	int ntype = IS_DNS;
624
625	if( ldap_int_hostname &&
626		( !name_in || !strcasecmp( name_in, "localhost" ) ) )
627	{
628		name = ldap_int_hostname;
629	} else {
630		name = name_in;
631	}
632
633	peer_cert_list = gnutls_certificate_get_peers( s->session,
634						&list_size );
635	if ( !peer_cert_list ) {
636		Debug( LDAP_DEBUG_ANY,
637			"TLS: unable to get peer certificate.\n",
638			0, 0, 0 );
639		/* If this was a fatal condition, things would have
640		 * aborted long before now.
641		 */
642		return LDAP_SUCCESS;
643	}
644	ret = gnutls_x509_crt_init( &cert );
645	if ( ret < 0 )
646		return LDAP_LOCAL_ERROR;
647	ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
648	if ( ret ) {
649		gnutls_x509_crt_deinit( cert );
650		return LDAP_LOCAL_ERROR;
651	}
652
653#ifdef LDAP_PF_INET6
654	if (name[0] == '[' && strchr(name, ']')) {
655		char *n2 = ldap_strdup(name+1);
656		*strchr(n2, ']') = 0;
657		if (inet_pton(AF_INET6, n2, &addr))
658			ntype = IS_IP6;
659		LDAP_FREE(n2);
660	} else
661#endif
662	if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
663		if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
664	}
665
666	if (ntype == IS_DNS) {
667		len1 = strlen(name);
668		domain = strchr(name, '.');
669		if (domain) {
670			len2 = len1 - (domain-name);
671		}
672	}
673
674	for ( i=0, ret=0; ret >= 0; i++ ) {
675		altnamesize = sizeof(altname);
676		ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
677			altname, &altnamesize, NULL );
678		if ( ret < 0 ) break;
679
680		/* ignore empty */
681		if ( altnamesize == 0 ) continue;
682
683		if ( ret == GNUTLS_SAN_DNSNAME ) {
684			if (ntype != IS_DNS) continue;
685
686			/* Is this an exact match? */
687			if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
688				break;
689			}
690
691			/* Is this a wildcard match? */
692			if (domain && (altname[0] == '*') && (altname[1] == '.') &&
693				(len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
694			{
695				break;
696			}
697		} else if ( ret == GNUTLS_SAN_IPADDRESS ) {
698			if (ntype == IS_DNS) continue;
699
700#ifdef LDAP_PF_INET6
701			if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
702				continue;
703			} else
704#endif
705			if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
706				continue;
707			}
708			if (!memcmp(altname, &addr, altnamesize)) {
709				break;
710			}
711		}
712	}
713	if ( ret >= 0 ) {
714		ret = LDAP_SUCCESS;
715	} else {
716		/* find the last CN */
717		i=0;
718		do {
719			altnamesize = 0;
720			ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
721				i, 1, altname, &altnamesize );
722			if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
723				i++;
724			else
725				break;
726		} while ( 1 );
727
728		if ( i ) {
729			altnamesize = sizeof(altname);
730			ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
731				i-1, 0, altname, &altnamesize );
732		}
733
734		if ( ret < 0 ) {
735			Debug( LDAP_DEBUG_ANY,
736				"TLS: unable to get common name from peer certificate.\n",
737				0, 0, 0 );
738			ret = LDAP_CONNECT_ERROR;
739			if ( ld->ld_error ) {
740				LDAP_FREE( ld->ld_error );
741			}
742			ld->ld_error = LDAP_STRDUP(
743				_("TLS: unable to get CN from peer certificate"));
744
745		} else {
746			ret = LDAP_LOCAL_ERROR;
747			if ( !len1 ) len1 = strlen( name );
748			if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
749				ret = LDAP_SUCCESS;
750
751			} else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
752					/* Is this a wildcard match? */
753				if( domain &&
754					(len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
755					ret = LDAP_SUCCESS;
756				}
757			}
758		}
759
760		if( ret == LDAP_LOCAL_ERROR ) {
761			altname[altnamesize] = '\0';
762			Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
763				"common name in certificate (%s).\n",
764				name, altname, 0 );
765			ret = LDAP_CONNECT_ERROR;
766			if ( ld->ld_error ) {
767				LDAP_FREE( ld->ld_error );
768			}
769			ld->ld_error = LDAP_STRDUP(
770				_("TLS: hostname does not match CN in peer certificate"));
771		}
772	}
773	gnutls_x509_crt_deinit( cert );
774	return ret;
775}
776
777static int
778tlsg_session_strength( tls_session *session )
779{
780	tlsg_session *s = (tlsg_session *)session;
781	gnutls_cipher_algorithm_t c;
782
783	c = gnutls_cipher_get( s->session );
784	return gnutls_cipher_get_key_size( c ) * 8;
785}
786
787/* suites is a string of colon-separated cipher suite names. */
788static int
789tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
790{
791#ifdef HAVE_CIPHERSUITES
792	const char *err;
793	return gnutls_priority_init( &ctx->prios, suites, &err );
794#else
795	char *ptr, *end;
796	int i, j, len, num;
797	int *list, nkx = 0, ncipher = 0, nmac = 0;
798	int *kx, *cipher, *mac;
799
800	num = 0;
801	ptr = suites;
802	do {
803		end = strchr(ptr, ':');
804		if ( end )
805			len = end - ptr;
806		else
807			len = strlen(ptr);
808		for (i=0; i<tlsg_n_ciphers; i++) {
809			if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
810				num++;
811				break;
812			}
813		}
814		if ( i == tlsg_n_ciphers ) {
815			/* unrecognized cipher suite */
816			return -1;
817		}
818		ptr += len + 1;
819	} while (end);
820
821	/* Space for all 3 lists */
822	list = LDAP_MALLOC( (num+1) * sizeof(int) * 3 );
823	if ( !list )
824		return -1;
825	kx = list;
826	cipher = kx+num+1;
827	mac = cipher+num+1;
828
829	ptr = suites;
830	do {
831		end = strchr(ptr, ':');
832		if ( end )
833			len = end - ptr;
834		else
835			len = strlen(ptr);
836		for (i=0; i<tlsg_n_ciphers; i++) {
837			/* For each cipher suite, insert its algorithms into
838			 * their respective priority lists. Make sure they
839			 * only appear once in each list.
840			 */
841			if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
842				for (j=0; j<nkx; j++)
843					if ( kx[j] == tlsg_ciphers[i].kx )
844						break;
845				if ( j == nkx )
846					kx[nkx++] = tlsg_ciphers[i].kx;
847				for (j=0; j<ncipher; j++)
848					if ( cipher[j] == tlsg_ciphers[i].cipher )
849						break;
850				if ( j == ncipher )
851					cipher[ncipher++] = tlsg_ciphers[i].cipher;
852				for (j=0; j<nmac; j++)
853					if ( mac[j] == tlsg_ciphers[i].mac )
854						break;
855				if ( j == nmac )
856					mac[nmac++] = tlsg_ciphers[i].mac;
857				break;
858			}
859		}
860		ptr += len + 1;
861	} while (end);
862	kx[nkx] = 0;
863	cipher[ncipher] = 0;
864	mac[nmac] = 0;
865	ctx->kx_list = kx;
866	ctx->cipher_list = cipher;
867	ctx->mac_list = mac;
868	return 0;
869#endif
870}
871
872/*
873 * TLS support for LBER Sockbufs
874 */
875
876struct tls_data {
877	tlsg_session		*session;
878	Sockbuf_IO_Desc		*sbiod;
879};
880
881static ssize_t
882tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
883{
884	struct tls_data		*p;
885
886	if ( buf == NULL || len <= 0 ) return 0;
887
888	p = (struct tls_data *)ptr;
889
890	if ( p == NULL || p->sbiod == NULL ) {
891		return 0;
892	}
893
894	return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
895}
896
897static ssize_t
898tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
899{
900	struct tls_data		*p;
901
902	if ( buf == NULL || len <= 0 ) return 0;
903
904	p = (struct tls_data *)ptr;
905
906	if ( p == NULL || p->sbiod == NULL ) {
907		return 0;
908	}
909
910	return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
911}
912
913static int
914tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
915{
916	struct tls_data		*p;
917	tlsg_session	*session = arg;
918
919	assert( sbiod != NULL );
920
921	p = LBER_MALLOC( sizeof( *p ) );
922	if ( p == NULL ) {
923		return -1;
924	}
925
926	gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
927	gnutls_transport_set_pull_function( session->session, tlsg_recv );
928	gnutls_transport_set_push_function( session->session, tlsg_send );
929	p->session = session;
930	p->sbiod = sbiod;
931	sbiod->sbiod_pvt = p;
932	return 0;
933}
934
935static int
936tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
937{
938	struct tls_data		*p;
939
940	assert( sbiod != NULL );
941	assert( sbiod->sbiod_pvt != NULL );
942
943	p = (struct tls_data *)sbiod->sbiod_pvt;
944	gnutls_deinit ( p->session->session );
945	LBER_FREE( p->session );
946	LBER_FREE( sbiod->sbiod_pvt );
947	sbiod->sbiod_pvt = NULL;
948	return 0;
949}
950
951static int
952tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
953{
954	struct tls_data		*p;
955
956	assert( sbiod != NULL );
957	assert( sbiod->sbiod_pvt != NULL );
958
959	p = (struct tls_data *)sbiod->sbiod_pvt;
960	gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
961	return 0;
962}
963
964static int
965tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
966{
967	struct tls_data		*p;
968
969	assert( sbiod != NULL );
970	assert( sbiod->sbiod_pvt != NULL );
971
972	p = (struct tls_data *)sbiod->sbiod_pvt;
973
974	if ( opt == LBER_SB_OPT_GET_SSL ) {
975		*((tlsg_session **)arg) = p->session;
976		return 1;
977
978	} else if ( opt == LBER_SB_OPT_DATA_READY ) {
979		if( gnutls_record_check_pending( p->session->session ) > 0 ) {
980			return 1;
981		}
982	}
983
984	return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
985}
986
987static ber_slen_t
988tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
989{
990	struct tls_data		*p;
991	ber_slen_t		ret;
992
993	assert( sbiod != NULL );
994	assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
995
996	p = (struct tls_data *)sbiod->sbiod_pvt;
997
998	ret = gnutls_record_recv ( p->session->session, buf, len );
999	switch (ret) {
1000	case GNUTLS_E_INTERRUPTED:
1001	case GNUTLS_E_AGAIN:
1002		sbiod->sbiod_sb->sb_trans_needs_read = 1;
1003		sock_errset(EWOULDBLOCK);
1004		ret = 0;
1005		break;
1006	case GNUTLS_E_REHANDSHAKE:
1007		for ( ret = gnutls_handshake ( p->session->session );
1008		      ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
1009		      ret = gnutls_handshake ( p->session->session ) );
1010		sbiod->sbiod_sb->sb_trans_needs_read = 1;
1011		ret = 0;
1012		break;
1013	default:
1014		sbiod->sbiod_sb->sb_trans_needs_read = 0;
1015	}
1016	return ret;
1017}
1018
1019static ber_slen_t
1020tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
1021{
1022	struct tls_data		*p;
1023	ber_slen_t		ret;
1024
1025	assert( sbiod != NULL );
1026	assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1027
1028	p = (struct tls_data *)sbiod->sbiod_pvt;
1029
1030	ret = gnutls_record_send ( p->session->session, (char *)buf, len );
1031
1032	if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
1033		sbiod->sbiod_sb->sb_trans_needs_write = 1;
1034		sock_errset(EWOULDBLOCK);
1035		ret = 0;
1036	} else {
1037		sbiod->sbiod_sb->sb_trans_needs_write = 0;
1038	}
1039	return ret;
1040}
1041
1042static Sockbuf_IO tlsg_sbio =
1043{
1044	tlsg_sb_setup,		/* sbi_setup */
1045	tlsg_sb_remove,		/* sbi_remove */
1046	tlsg_sb_ctrl,		/* sbi_ctrl */
1047	tlsg_sb_read,		/* sbi_read */
1048	tlsg_sb_write,		/* sbi_write */
1049	tlsg_sb_close		/* sbi_close */
1050};
1051
1052/* Certs are not automatically varified during the handshake */
1053static int
1054tlsg_cert_verify( tlsg_session *ssl )
1055{
1056	unsigned int status = 0;
1057	int err;
1058	time_t now = time(0);
1059	time_t peertime;
1060
1061	err = gnutls_certificate_verify_peers2( ssl->session, &status );
1062	if ( err < 0 ) {
1063		Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
1064			err,0,0 );
1065		return -1;
1066	}
1067	if ( status ) {
1068		Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
1069			status, 0,0 );
1070		return -1;
1071	}
1072	peertime = gnutls_certificate_expiration_time_peers( ssl->session );
1073	if ( peertime == (time_t) -1 ) {
1074		Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
1075			0, 0, 0 );
1076		return -1;
1077	}
1078	if ( peertime < now ) {
1079		Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
1080			0, 0, 0 );
1081		return -1;
1082	}
1083	peertime = gnutls_certificate_activation_time_peers( ssl->session );
1084	if ( peertime == (time_t) -1 ) {
1085		Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
1086			0, 0, 0 );
1087		return -1;
1088	}
1089	if ( peertime > now ) {
1090		Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
1091			0, 0, 0 );
1092		return -1;
1093	}
1094	return 0;
1095}
1096
1097tls_impl ldap_int_tls_impl = {
1098	"GnuTLS",
1099
1100	tlsg_init,
1101	tlsg_destroy,
1102
1103	tlsg_ctx_new,
1104	tlsg_ctx_ref,
1105	tlsg_ctx_free,
1106	tlsg_ctx_init,
1107
1108	tlsg_session_new,
1109	tlsg_session_connect,
1110	tlsg_session_accept,
1111	tlsg_session_upflags,
1112	tlsg_session_errmsg,
1113	tlsg_session_my_dn,
1114	tlsg_session_peer_dn,
1115	tlsg_session_chkhost,
1116	tlsg_session_strength,
1117
1118	&tlsg_sbio,
1119
1120#ifdef LDAP_R_COMPILE
1121	tlsg_thr_init,
1122#else
1123	NULL,
1124#endif
1125
1126	0
1127};
1128
1129#endif /* HAVE_GNUTLS */
1130