git.sur5r.net Git - openldap/blob - libraries/libldap/tls_g.c

   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 2008-2018 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  * Emily 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
  47 typedef struct tlsg_ctx {
  48         gnutls_certificate_credentials_t cred;
  49         gnutls_dh_params_t dh_params;
  50         unsigned long verify_depth;
  51         int refcount;
  52         int reqcert;
  53         gnutls_priority_t prios;
  54 #ifdef LDAP_R_COMPILE
  55         ldap_pvt_thread_mutex_t ref_mutex;
  56 #endif
  57 } tlsg_ctx;
  58
  59 typedef struct tlsg_session {
  60         gnutls_session_t session;
  61         tlsg_ctx *ctx;
  62         struct berval peer_der_dn;
  63 } tlsg_session;
  64
  65 static int tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites );
  66 static int tlsg_cert_verify( tlsg_session *s );
  67
  68 #ifdef LDAP_R_COMPILE
  69
  70 static int
  71 tlsg_mutex_init( void **priv )
  72 {
  73         int err = 0;
  74         ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t ));
  75
  76         if ( !lock )
  77                 err = ENOMEM;
  78         if ( !err ) {
  79                 err = ldap_pvt_thread_mutex_init( lock );
  80                 if ( err )
  81                         LDAP_FREE( lock );
  82                 else
  83                         *priv = lock;
  84         }
  85         return err;
  86 }
  87
  88 static int
  89 tlsg_mutex_destroy( void **lock )
  90 {
  91         int err = ldap_pvt_thread_mutex_destroy( *lock );
  92         LDAP_FREE( *lock );
  93         return err;
  94 }
  95
  96 static int
  97 tlsg_mutex_lock( void **lock )
  98 {
  99         return ldap_pvt_thread_mutex_lock( *lock );
 100 }
 101
 102 static int
 103 tlsg_mutex_unlock( void **lock )
 104 {
 105         return ldap_pvt_thread_mutex_unlock( *lock );
 106 }
 107
 108 static void
 109 tlsg_thr_init( void )
 110 {
 111         gnutls_global_set_mutex (tlsg_mutex_init,
 112                 tlsg_mutex_destroy,
 113                 tlsg_mutex_lock,
 114                 tlsg_mutex_unlock);
 115 }
 116 #endif /* LDAP_R_COMPILE */
 117
 118 /*
 119  * Initialize TLS subsystem. Should be called only once.
 120  */
 121 static int
 122 tlsg_init( void )
 123 {
 124         gnutls_global_init();
 125         return 0;
 126 }
 127
 128 /*
 129  * Tear down the TLS subsystem. Should only be called once.
 130  */
 131 static void
 132 tlsg_destroy( void )
 133 {
 134         gnutls_global_deinit();
 135 }
 136
 137 static tls_ctx *
 138 tlsg_ctx_new ( struct ldapoptions *lo )
 139 {
 140         tlsg_ctx *ctx;
 141
 142         ctx = ber_memcalloc ( 1, sizeof (*ctx) );
 143         if ( ctx ) {
 144                 if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
 145                         ber_memfree( ctx );
 146                         return NULL;
 147                 }
 148                 ctx->refcount = 1;
 149                 gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
 150 #ifdef LDAP_R_COMPILE
 151                 ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
 152 #endif
 153         }
 154         return (tls_ctx *)ctx;
 155 }
 156
 157 static void
 158 tlsg_ctx_ref( tls_ctx *ctx )
 159 {
 160         tlsg_ctx *c = (tlsg_ctx *)ctx;
 161         LDAP_MUTEX_LOCK( &c->ref_mutex );
 162         c->refcount++;
 163         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 164 }
 165
 166 static void
 167 tlsg_ctx_free ( tls_ctx *ctx )
 168 {
 169         tlsg_ctx *c = (tlsg_ctx *)ctx;
 170         int refcount;
 171
 172         if ( !c ) return;
 173
 174         LDAP_MUTEX_LOCK( &c->ref_mutex );
 175         refcount = --c->refcount;
 176         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 177         if ( refcount )
 178                 return;
 179         gnutls_priority_deinit( c->prios );
 180         gnutls_certificate_free_credentials( c->cred );
 181         if ( c->dh_params )
 182                 gnutls_dh_params_deinit( c->dh_params );
 183         ber_memfree ( c );
 184 }
 185
 186 static int
 187 tlsg_getfile( const char *path, gnutls_datum_t *buf )
 188 {
 189         int rc = -1, fd;
 190         struct stat st;
 191
 192         fd = open( path, O_RDONLY );
 193         if ( fd >= 0 && fstat( fd, &st ) == 0 ) {
 194                 buf->size = st.st_size;
 195                 buf->data = LDAP_MALLOC( st.st_size + 1 );
 196                 if ( buf->data ) {
 197                         rc = read( fd, buf->data, st.st_size );
 198                         close( fd );
 199                         if ( rc < st.st_size )
 200                                 rc = -1;
 201                         else
 202                                 rc = 0;
 203                 }
 204         }
 205         return rc;
 206 }
 207
 208 /* This is the GnuTLS default */
 209 #define VERIFY_DEPTH    6
 210
 211 /*
 212  * initialize a new TLS context
 213  */
 214 static int
 215 tlsg_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
 216 {
 217         tlsg_ctx *ctx = lo->ldo_tls_ctx;
 218         int rc;
 219
 220         if ( lo->ldo_tls_ciphersuite &&
 221                 tlsg_parse_ciphers( ctx, lt->lt_ciphersuite )) {
 222                 Debug( LDAP_DEBUG_ANY,
 223                            "TLS: could not set cipher list %s.\n",
 224                            lo->ldo_tls_ciphersuite, 0, 0 );
 225                 return -1;
 226         }
 227
 228         if (lo->ldo_tls_cacertdir != NULL) {
 229                 Debug( LDAP_DEBUG_ANY,
 230                        "TLS: warning: cacertdir not implemented for gnutls\n",
 231                        NULL, NULL, NULL );
 232         }
 233
 234         if (lo->ldo_tls_cacertfile != NULL) {
 235                 rc = gnutls_certificate_set_x509_trust_file(
 236                         ctx->cred,
 237                         lt->lt_cacertfile,
 238                         GNUTLS_X509_FMT_PEM );
 239                 if ( rc < 0 ) return -1;
 240         }
 241
 242         if ( lo->ldo_tls_certfile && lo->ldo_tls_keyfile ) {
 243                 gnutls_x509_privkey_t key;
 244                 gnutls_datum_t buf;
 245                 gnutls_x509_crt_t certs[VERIFY_DEPTH];
 246                 unsigned int max = VERIFY_DEPTH;
 247
 248                 rc = gnutls_x509_privkey_init( &key );
 249                 if ( rc ) return -1;
 250
 251                 /* OpenSSL builds the cert chain for us, but GnuTLS
 252                  * expects it to be present in the certfile. If it's
 253                  * not, we have to build it ourselves. So we have to
 254                  * do some special checks here...
 255                  */
 256                 rc = tlsg_getfile( lt->lt_keyfile, &buf );
 257                 if ( rc ) return -1;
 258                 rc = gnutls_x509_privkey_import( key, &buf,
 259                         GNUTLS_X509_FMT_PEM );
 260                 LDAP_FREE( buf.data );
 261                 if ( rc < 0 ) return rc;
 262
 263                 rc = tlsg_getfile( lt->lt_certfile, &buf );
 264                 if ( rc ) return -1;
 265                 rc = gnutls_x509_crt_list_import( certs, &max, &buf,
 266                         GNUTLS_X509_FMT_PEM, 0 );
 267                 LDAP_FREE( buf.data );
 268                 if ( rc < 0 ) return rc;
 269
 270                 /* If there's only one cert and it's not self-signed,
 271                  * then we have to build the cert chain.
 272                  */
 273                 if ( max == 1 && !gnutls_x509_crt_check_issuer( certs[0], certs[0] )) {
 274                         unsigned int i;
 275                         for ( i = 1; i<VERIFY_DEPTH; i++ ) {
 276                                 if ( gnutls_certificate_get_issuer( ctx->cred, certs[i-1], &certs[i], 0 ))
 277                                         break;
 278                                 max++;
 279                                 /* If this CA is self-signed, we're done */
 280                                 if ( gnutls_x509_crt_check_issuer( certs[i], certs[i] ))
 281                                         break;
 282                         }
 283                 }
 284                 rc = gnutls_certificate_set_x509_key( ctx->cred, certs, max, key );
 285                 if ( rc ) return -1;
 286         } else if ( lo->ldo_tls_certfile || lo->ldo_tls_keyfile ) {
 287                 Debug( LDAP_DEBUG_ANY,
 288                        "TLS: only one of certfile and keyfile specified\n",
 289                        NULL, NULL, NULL );
 290                 return -1;
 291         }
 292
 293         if ( lo->ldo_tls_crlfile ) {
 294                 rc = gnutls_certificate_set_x509_crl_file(
 295                         ctx->cred,
 296                         lt->lt_crlfile,
 297                         GNUTLS_X509_FMT_PEM );
 298                 if ( rc < 0 ) return -1;
 299                 rc = 0;
 300         }
 301
 302         /* FIXME: ITS#5992 - this should be configurable,
 303          * and V1 CA certs should be phased out ASAP.
 304          */
 305         gnutls_certificate_set_verify_flags( ctx->cred,
 306                 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
 307
 308         if ( is_server && lo->ldo_tls_dhfile ) {
 309                 gnutls_datum_t buf;
 310                 rc = tlsg_getfile( lo->ldo_tls_dhfile, &buf );
 311                 if ( rc ) return -1;
 312                 rc = gnutls_dh_params_init( &ctx->dh_params );
 313                 if ( rc == 0 )
 314                         rc = gnutls_dh_params_import_pkcs3( ctx->dh_params, &buf,
 315                                 GNUTLS_X509_FMT_PEM );
 316                 LDAP_FREE( buf.data );
 317                 if ( rc ) return -1;
 318                 gnutls_certificate_set_dh_params( ctx->cred, ctx->dh_params );
 319         }
 320
 321         ctx->reqcert = lo->ldo_tls_require_cert;
 322
 323         return 0;
 324 }
 325
 326 static tls_session *
 327 tlsg_session_new ( tls_ctx * ctx, int is_server )
 328 {
 329         tlsg_ctx *c = (tlsg_ctx *)ctx;
 330         tlsg_session *session;
 331
 332         session = ber_memcalloc ( 1, sizeof (*session) );
 333         if ( !session )
 334                 return NULL;
 335
 336         session->ctx = c;
 337         gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
 338         gnutls_priority_set( session->session, c->prios );
 339         if ( c->cred )
 340                 gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
 341
 342         if ( is_server ) {
 343                 int flag = 0;
 344                 if ( c->reqcert ) {
 345                         flag = GNUTLS_CERT_REQUEST;
 346                         if ( c->reqcert == LDAP_OPT_X_TLS_DEMAND ||
 347                                 c->reqcert == LDAP_OPT_X_TLS_HARD )
 348                                 flag = GNUTLS_CERT_REQUIRE;
 349                         gnutls_certificate_server_set_request( session->session, flag );
 350                 }
 351         }
 352         return (tls_session *)session;
 353 }
 354
 355 static int
 356 tlsg_session_accept( tls_session *session )
 357 {
 358         tlsg_session *s = (tlsg_session *)session;
 359         int rc;
 360
 361         for ( rc = gnutls_handshake ( s->session );
 362               rc == GNUTLS_E_INTERRUPTED || rc == GNUTLS_E_AGAIN;
 363               rc = gnutls_handshake ( s->session ) );
 364         if ( rc == 0 && s->ctx->reqcert != LDAP_OPT_X_TLS_NEVER ) {
 365                 const gnutls_datum_t *peer_cert_list;
 366                 unsigned int list_size;
 367
 368                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 369                                                 &list_size );
 370                 if ( !peer_cert_list && s->ctx->reqcert == LDAP_OPT_X_TLS_TRY )
 371                         rc = 0;
 372                 else {
 373                         rc = tlsg_cert_verify( s );
 374                         if ( rc && s->ctx->reqcert == LDAP_OPT_X_TLS_ALLOW )
 375                                 rc = 0;
 376                 }
 377         }
 378         return rc;
 379 }
 380
 381 static int
 382 tlsg_session_connect( LDAP *ld, tls_session *session )
 383 {
 384         return tlsg_session_accept( session);
 385 }
 386
 387 static int
 388 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 389 {
 390         tlsg_session *s = (tlsg_session *)session;
 391
 392         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 393                 return 0;
 394
 395         switch (gnutls_record_get_direction (s->session)) {
 396         case 0:
 397                 sb->sb_trans_needs_read = 1;
 398                 return 1;
 399         case 1:
 400                 sb->sb_trans_needs_write = 1;
 401                 return 1;
 402         }
 403         return 0;
 404 }
 405
 406 static char *
 407 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 408 {
 409         return (char *)gnutls_strerror( rc );
 410 }
 411
 412 static void
 413 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 414 {
 415         BerElementBuffer berbuf;
 416         BerElement *ber = (BerElement *)&berbuf;
 417         ber_tag_t tag;
 418         ber_len_t len;
 419         ber_int_t i;
 420
 421         ber_init2( ber, cert, LBER_USE_DER );
 422         tag = ber_skip_tag( ber, &len );        /* Sequence */
 423         tag = ber_skip_tag( ber, &len );        /* Sequence */
 424         tag = ber_peek_tag( ber, &len );        /* Context + Constructed (version) */
 425         if ( tag == 0xa0 ) {    /* Version is optional */
 426                 tag = ber_skip_tag( ber, &len );
 427                 tag = ber_get_int( ber, &i );   /* Int: Version */
 428         }
 429         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 430         ber_skip_data( ber, len );
 431         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 432         ber_skip_data( ber, len );
 433         if ( !get_subject ) {
 434                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 435         } else {
 436                 tag = ber_skip_tag( ber, &len );
 437                 ber_skip_data( ber, len );
 438                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 439                 ber_skip_data( ber, len );
 440                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 441         }
 442         len = ber_ptrlen( ber );
 443         dn->bv_val = cert->bv_val + len;
 444         dn->bv_len = cert->bv_len - len;
 445 }
 446
 447 static int
 448 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 449 {
 450         tlsg_session *s = (tlsg_session *)session;
 451         const gnutls_datum_t *x;
 452         struct berval bv;
 453
 454         x = gnutls_certificate_get_ours( s->session );
 455
 456         if (!x) return LDAP_INVALID_CREDENTIALS;
 457
 458         bv.bv_val = (char *) x->data;
 459         bv.bv_len = x->size;
 460
 461         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 462         return 0;
 463 }
 464
 465 static int
 466 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 467 {
 468         tlsg_session *s = (tlsg_session *)session;
 469         if ( !s->peer_der_dn.bv_val ) {
 470                 const gnutls_datum_t *peer_cert_list;
 471                 unsigned int list_size;
 472                 struct berval bv;
 473
 474                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 475                                                         &list_size );
 476                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 477
 478                 bv.bv_len = peer_cert_list->size;
 479                 bv.bv_val = (char *) peer_cert_list->data;
 480
 481                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 482         }
 483         *der_dn = s->peer_der_dn;
 484         return 0;
 485 }
 486
 487 /* what kind of hostname were we given? */
 488 #define IS_DNS  0
 489 #define IS_IP4  1
 490 #define IS_IP6  2
 491
 492 #define CN_OID  "2.5.4.3"
 493
 494 static int
 495 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 496 {
 497         tlsg_session *s = (tlsg_session *)session;
 498         int i, ret;
 499         const gnutls_datum_t *peer_cert_list;
 500         unsigned int list_size;
 501         char altname[NI_MAXHOST];
 502         size_t altnamesize;
 503
 504         gnutls_x509_crt_t cert;
 505         const char *name;
 506         char *ptr;
 507         char *domain = NULL;
 508 #ifdef LDAP_PF_INET6
 509         struct in6_addr addr;
 510 #else
 511         struct in_addr addr;
 512 #endif
 513         int len1 = 0, len2 = 0;
 514         int ntype = IS_DNS;
 515
 516         if( ldap_int_hostname &&
 517                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 518         {
 519                 name = ldap_int_hostname;
 520         } else {
 521                 name = name_in;
 522         }
 523
 524         peer_cert_list = gnutls_certificate_get_peers( s->session,
 525                                                 &list_size );
 526         if ( !peer_cert_list ) {
 527                 Debug( LDAP_DEBUG_ANY,
 528                         "TLS: unable to get peer certificate.\n",
 529                         0, 0, 0 );
 530                 /* If this was a fatal condition, things would have
 531                  * aborted long before now.
 532                  */
 533                 return LDAP_SUCCESS;
 534         }
 535         ret = gnutls_x509_crt_init( &cert );
 536         if ( ret < 0 )
 537                 return LDAP_LOCAL_ERROR;
 538         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 539         if ( ret ) {
 540                 gnutls_x509_crt_deinit( cert );
 541                 return LDAP_LOCAL_ERROR;
 542         }
 543
 544 #ifdef LDAP_PF_INET6
 545         if (inet_pton(AF_INET6, name, &addr)) {
 546                 ntype = IS_IP6;
 547         } else
 548 #endif
 549         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 550                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 551         }
 552
 553         if (ntype == IS_DNS) {
 554                 len1 = strlen(name);
 555                 domain = strchr(name, '.');
 556                 if (domain) {
 557                         len2 = len1 - (domain-name);
 558                 }
 559         }
 560
 561         for ( i=0, ret=0; ret >= 0; i++ ) {
 562                 altnamesize = sizeof(altname);
 563                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 564                         altname, &altnamesize, NULL );
 565                 if ( ret < 0 ) break;
 566
 567                 /* ignore empty */
 568                 if ( altnamesize == 0 ) continue;
 569
 570                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 571                         if (ntype != IS_DNS) continue;
 572
 573                         /* Is this an exact match? */
 574                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 575                                 break;
 576                         }
 577
 578                         /* Is this a wildcard match? */
 579                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 580                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 581                         {
 582                                 break;
 583                         }
 584                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 585                         if (ntype == IS_DNS) continue;
 586
 587 #ifdef LDAP_PF_INET6
 588                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 589                                 continue;
 590                         } else
 591 #endif
 592                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 593                                 continue;
 594                         }
 595                         if (!memcmp(altname, &addr, altnamesize)) {
 596                                 break;
 597                         }
 598                 }
 599         }
 600         if ( ret >= 0 ) {
 601                 ret = LDAP_SUCCESS;
 602         } else {
 603                 /* find the last CN */
 604                 i=0;
 605                 do {
 606                         altnamesize = 0;
 607                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 608                                 i, 1, altname, &altnamesize );
 609                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 610                                 i++;
 611                         else
 612                                 break;
 613                 } while ( 1 );
 614
 615                 if ( i ) {
 616                         altnamesize = sizeof(altname);
 617                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 618                                 i-1, 0, altname, &altnamesize );
 619                 }
 620
 621                 if ( ret < 0 ) {
 622                         Debug( LDAP_DEBUG_ANY,
 623                                 "TLS: unable to get common name from peer certificate.\n",
 624                                 0, 0, 0 );
 625                         ret = LDAP_CONNECT_ERROR;
 626                         if ( ld->ld_error ) {
 627                                 LDAP_FREE( ld->ld_error );
 628                         }
 629                         ld->ld_error = LDAP_STRDUP(
 630                                 _("TLS: unable to get CN from peer certificate"));
 631
 632                 } else {
 633                         ret = LDAP_LOCAL_ERROR;
 634                         if ( !len1 ) len1 = strlen( name );
 635                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 636                                 ret = LDAP_SUCCESS;
 637
 638                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 639                                         /* Is this a wildcard match? */
 640                                 if( domain &&
 641                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 642                                         ret = LDAP_SUCCESS;
 643                                 }
 644                         }
 645                 }
 646
 647                 if( ret == LDAP_LOCAL_ERROR ) {
 648                         altname[altnamesize] = '\0';
 649                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 650                                 "common name in certificate (%s).\n",
 651                                 name, altname, 0 );
 652                         ret = LDAP_CONNECT_ERROR;
 653                         if ( ld->ld_error ) {
 654                                 LDAP_FREE( ld->ld_error );
 655                         }
 656                         ld->ld_error = LDAP_STRDUP(
 657                                 _("TLS: hostname does not match CN in peer certificate"));
 658                 }
 659         }
 660         gnutls_x509_crt_deinit( cert );
 661         return ret;
 662 }
 663
 664 static int
 665 tlsg_session_strength( tls_session *session )
 666 {
 667         tlsg_session *s = (tlsg_session *)session;
 668         gnutls_cipher_algorithm_t c;
 669
 670         c = gnutls_cipher_get( s->session );
 671         return gnutls_cipher_get_key_size( c ) * 8;
 672 }
 673
 674 /* suites is a string of colon-separated cipher suite names. */
 675 static int
 676 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 677 {
 678         const char *err;
 679         int rc = gnutls_priority_init( &ctx->prios, suites, &err );
 680         if ( rc )
 681                 ctx->prios = NULL;
 682         return rc;
 683 }
 684
 685 /*
 686  * TLS support for LBER Sockbufs
 687  */
 688
 689 struct tls_data {
 690         tlsg_session            *session;
 691         Sockbuf_IO_Desc         *sbiod;
 692 };
 693
 694 static ssize_t
 695 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 696 {
 697         struct tls_data         *p;
 698
 699         if ( buf == NULL || len <= 0 ) return 0;
 700
 701         p = (struct tls_data *)ptr;
 702
 703         if ( p == NULL || p->sbiod == NULL ) {
 704                 return 0;
 705         }
 706
 707         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 708 }
 709
 710 static ssize_t
 711 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 712 {
 713         struct tls_data         *p;
 714
 715         if ( buf == NULL || len <= 0 ) return 0;
 716
 717         p = (struct tls_data *)ptr;
 718
 719         if ( p == NULL || p->sbiod == NULL ) {
 720                 return 0;
 721         }
 722
 723         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 724 }
 725
 726 static int
 727 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 728 {
 729         struct tls_data         *p;
 730         tlsg_session    *session = arg;
 731
 732         assert( sbiod != NULL );
 733
 734         p = LBER_MALLOC( sizeof( *p ) );
 735         if ( p == NULL ) {
 736                 return -1;
 737         }
 738
 739         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 740         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 741         gnutls_transport_set_push_function( session->session, tlsg_send );
 742         p->session = session;
 743         p->sbiod = sbiod;
 744         sbiod->sbiod_pvt = p;
 745         return 0;
 746 }
 747
 748 static int
 749 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 750 {
 751         struct tls_data         *p;
 752
 753         assert( sbiod != NULL );
 754         assert( sbiod->sbiod_pvt != NULL );
 755
 756         p = (struct tls_data *)sbiod->sbiod_pvt;
 757         gnutls_deinit ( p->session->session );
 758         LBER_FREE( p->session );
 759         LBER_FREE( sbiod->sbiod_pvt );
 760         sbiod->sbiod_pvt = NULL;
 761         return 0;
 762 }
 763
 764 static int
 765 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 766 {
 767         struct tls_data         *p;
 768
 769         assert( sbiod != NULL );
 770         assert( sbiod->sbiod_pvt != NULL );
 771
 772         p = (struct tls_data *)sbiod->sbiod_pvt;
 773         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 774         return 0;
 775 }
 776
 777 static int
 778 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 779 {
 780         struct tls_data         *p;
 781
 782         assert( sbiod != NULL );
 783         assert( sbiod->sbiod_pvt != NULL );
 784
 785         p = (struct tls_data *)sbiod->sbiod_pvt;
 786
 787         if ( opt == LBER_SB_OPT_GET_SSL ) {
 788                 *((tlsg_session **)arg) = p->session;
 789                 return 1;
 790
 791         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 792                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 793                         return 1;
 794                 }
 795         }
 796
 797         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 798 }
 799
 800 static ber_slen_t
 801 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 802 {
 803         struct tls_data         *p;
 804         ber_slen_t              ret;
 805
 806         assert( sbiod != NULL );
 807         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 808
 809         p = (struct tls_data *)sbiod->sbiod_pvt;
 810
 811         ret = gnutls_record_recv ( p->session->session, buf, len );
 812         switch (ret) {
 813         case GNUTLS_E_INTERRUPTED:
 814         case GNUTLS_E_AGAIN:
 815                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 816                 sock_errset(EWOULDBLOCK);
 817                 ret = 0;
 818                 break;
 819         case GNUTLS_E_REHANDSHAKE:
 820                 for ( ret = gnutls_handshake ( p->session->session );
 821                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
 822                       ret = gnutls_handshake ( p->session->session ) );
 823                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 824                 ret = 0;
 825                 break;
 826         default:
 827                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
 828         }
 829         return ret;
 830 }
 831
 832 static ber_slen_t
 833 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 834 {
 835         struct tls_data         *p;
 836         ber_slen_t              ret;
 837
 838         assert( sbiod != NULL );
 839         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 840
 841         p = (struct tls_data *)sbiod->sbiod_pvt;
 842
 843         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
 844
 845         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
 846                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
 847                 sock_errset(EWOULDBLOCK);
 848                 ret = 0;
 849         } else {
 850                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
 851         }
 852         return ret;
 853 }
 854
 855 static Sockbuf_IO tlsg_sbio =
 856 {
 857         tlsg_sb_setup,          /* sbi_setup */
 858         tlsg_sb_remove,         /* sbi_remove */
 859         tlsg_sb_ctrl,           /* sbi_ctrl */
 860         tlsg_sb_read,           /* sbi_read */
 861         tlsg_sb_write,          /* sbi_write */
 862         tlsg_sb_close           /* sbi_close */
 863 };
 864
 865 /* Certs are not automatically varified during the handshake */
 866 static int
 867 tlsg_cert_verify( tlsg_session *ssl )
 868 {
 869         unsigned int status = 0;
 870         int err;
 871         time_t now = time(0);
 872         time_t peertime;
 873
 874         err = gnutls_certificate_verify_peers2( ssl->session, &status );
 875         if ( err < 0 ) {
 876                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
 877                         err,0,0 );
 878                 return -1;
 879         }
 880         if ( status ) {
 881                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
 882                         status, 0,0 );
 883                 return -1;
 884         }
 885         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
 886         if ( peertime == (time_t) -1 ) {
 887                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
 888                         0, 0, 0 );
 889                 return -1;
 890         }
 891         if ( peertime < now ) {
 892                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
 893                         0, 0, 0 );
 894                 return -1;
 895         }
 896         peertime = gnutls_certificate_activation_time_peers( ssl->session );
 897         if ( peertime == (time_t) -1 ) {
 898                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
 899                         0, 0, 0 );
 900                 return -1;
 901         }
 902         if ( peertime > now ) {
 903                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
 904                         0, 0, 0 );
 905                 return -1;
 906         }
 907         return 0;
 908 }
 909
 910 tls_impl ldap_int_tls_impl = {
 911         "GnuTLS",
 912
 913         tlsg_init,
 914         tlsg_destroy,
 915
 916         tlsg_ctx_new,
 917         tlsg_ctx_ref,
 918         tlsg_ctx_free,
 919         tlsg_ctx_init,
 920
 921         tlsg_session_new,
 922         tlsg_session_connect,
 923         tlsg_session_accept,
 924         tlsg_session_upflags,
 925         tlsg_session_errmsg,
 926         tlsg_session_my_dn,
 927         tlsg_session_peer_dn,
 928         tlsg_session_chkhost,
 929         tlsg_session_strength,
 930
 931         &tlsg_sbio,
 932
 933 #ifdef LDAP_R_COMPILE
 934         tlsg_thr_init,
 935 #else
 936         NULL,
 937 #endif
 938
 939         0
 940 };
 941
 942 #endif /* HAVE_GNUTLS */