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 2008-2011 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 #ifdef LDAP_R_COMPILE
  45 #include <ldap_pvt_thread.h>
  46 #endif
  47
  48 #include <gnutls/gnutls.h>
  49 #include <gnutls/x509.h>
  50 #include <gcrypt.h>
  51
  52 #define DH_BITS (1024)
  53
  54 #if LIBGNUTLS_VERSION_NUMBER >= 0x020200
  55 #define HAVE_CIPHERSUITES       1
  56 /* This is a kludge. gcrypt 1.4.x has support. Recent GnuTLS requires gcrypt 1.4.x
  57  * but that dependency isn't reflected in their configure script, resulting in
  58  * build errors on older gcrypt. So, if they have a working build environment,
  59  * assume gcrypt is new enough.
  60  */
  61 #define HAVE_GCRYPT_RAND        1
  62 #else
  63 #undef HAVE_CIPHERSUITES
  64 #undef HAVE_GCRYPT_RAND
  65 #endif
  66
  67 #ifndef HAVE_CIPHERSUITES
  68 /* Versions prior to 2.2.0 didn't handle cipher suites, so we had to
  69  * kludge them ourselves.
  70  */
  71 typedef struct tls_cipher_suite {
  72         const char *name;
  73         gnutls_kx_algorithm_t kx;
  74         gnutls_cipher_algorithm_t cipher;
  75         gnutls_mac_algorithm_t mac;
  76         gnutls_protocol_t version;
  77 } tls_cipher_suite;
  78 #endif
  79
  80 typedef struct tlsg_ctx {
  81         struct ldapoptions *lo;
  82         gnutls_certificate_credentials_t cred;
  83         gnutls_dh_params_t dh_params;
  84         unsigned long verify_depth;
  85         int refcount;
  86 #ifdef HAVE_CIPHERSUITES
  87         gnutls_priority_t prios;
  88 #else
  89         int *kx_list;
  90         int *cipher_list;
  91         int *mac_list;
  92 #endif
  93 #ifdef LDAP_R_COMPILE
  94         ldap_pvt_thread_mutex_t ref_mutex;
  95 #endif
  96 } tlsg_ctx;
  97
  98 typedef struct tlsg_session {
  99         gnutls_session_t session;
 100         tlsg_ctx *ctx;
 101         struct berval peer_der_dn;
 102 } tlsg_session;
 103
 104 #ifndef HAVE_CIPHERSUITES
 105 static tls_cipher_suite *tlsg_ciphers;
 106 static int tlsg_n_ciphers;
 107 #endif
 108
 109 static int tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites );
 110 static int tlsg_cert_verify( tlsg_session *s );
 111
 112 #ifdef LDAP_R_COMPILE
 113
 114 static int
 115 tlsg_mutex_init( void **priv )
 116 {
 117         int err = 0;
 118         ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t ));
 119
 120         if ( !lock )
 121                 err = ENOMEM;
 122         if ( !err ) {
 123                 err = ldap_pvt_thread_mutex_init( lock );
 124                 if ( err )
 125                         LDAP_FREE( lock );
 126                 else
 127                         *priv = lock;
 128         }
 129         return err;
 130 }
 131
 132 static int
 133 tlsg_mutex_destroy( void **lock )
 134 {
 135         int err = ldap_pvt_thread_mutex_destroy( *lock );
 136         LDAP_FREE( *lock );
 137         return err;
 138 }
 139
 140 static int
 141 tlsg_mutex_lock( void **lock )
 142 {
 143         return ldap_pvt_thread_mutex_lock( *lock );
 144 }
 145
 146 static int
 147 tlsg_mutex_unlock( void **lock )
 148 {
 149         return ldap_pvt_thread_mutex_unlock( *lock );
 150 }
 151
 152 static struct gcry_thread_cbs tlsg_thread_cbs = {
 153         GCRY_THREAD_OPTION_USER,
 154         NULL,
 155         tlsg_mutex_init,
 156         tlsg_mutex_destroy,
 157         tlsg_mutex_lock,
 158         tlsg_mutex_unlock,
 159         NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
 160 };
 161
 162 static void
 163 tlsg_thr_init( void )
 164 {
 165         gcry_control (GCRYCTL_SET_THREAD_CBS, &tlsg_thread_cbs);
 166 }
 167 #endif /* LDAP_R_COMPILE */
 168
 169 /*
 170  * Initialize TLS subsystem. Should be called only once.
 171  */
 172 static int
 173 tlsg_init( void )
 174 {
 175 #ifdef HAVE_GCRYPT_RAND
 176         struct ldapoptions *lo = LDAP_INT_GLOBAL_OPT();
 177         if ( lo->ldo_tls_randfile &&
 178                 gcry_control( GCRYCTL_SET_RNDEGD_SOCKET, lo->ldo_tls_randfile )) {
 179                 Debug( LDAP_DEBUG_ANY,
 180                 "TLS: gcry_control GCRYCTL_SET_RNDEGD_SOCKET failed\n",
 181                 0, 0, 0);
 182                 return -1;
 183         }
 184 #endif
 185
 186         gnutls_global_init();
 187
 188 #ifndef HAVE_CIPHERSUITES
 189         /* GNUtls cipher suite handling: The library ought to parse suite
 190          * names for us, but it doesn't. It will return a list of suite names
 191          * that it supports, so we can do parsing ourselves. It ought to tell
 192          * us how long the list is, but it doesn't do that either, so we just
 193          * have to count it manually...
 194          */
 195         {
 196                 int i = 0;
 197                 tls_cipher_suite *ptr, tmp;
 198                 char cs_id[2];
 199
 200                 while ( gnutls_cipher_suite_info( i, cs_id, &tmp.kx, &tmp.cipher,
 201                         &tmp.mac, &tmp.version ))
 202                         i++;
 203                 tlsg_n_ciphers = i;
 204
 205                 /* Store a copy */
 206                 tlsg_ciphers = LDAP_MALLOC(tlsg_n_ciphers * sizeof(tls_cipher_suite));
 207                 if ( !tlsg_ciphers )
 208                         return -1;
 209                 for ( i=0; i<tlsg_n_ciphers; i++ ) {
 210                         tlsg_ciphers[i].name = gnutls_cipher_suite_info( i, cs_id,
 211                                 &tlsg_ciphers[i].kx, &tlsg_ciphers[i].cipher, &tlsg_ciphers[i].mac,
 212                                 &tlsg_ciphers[i].version );
 213                 }
 214         }
 215 #endif
 216         return 0;
 217 }
 218
 219 /*
 220  * Tear down the TLS subsystem. Should only be called once.
 221  */
 222 static void
 223 tlsg_destroy( void )
 224 {
 225 #ifndef HAVE_CIPHERSUITES
 226         LDAP_FREE( tlsg_ciphers );
 227         tlsg_ciphers = NULL;
 228         tlsg_n_ciphers = 0;
 229 #endif
 230         gnutls_global_deinit();
 231 }
 232
 233 static tls_ctx *
 234 tlsg_ctx_new ( struct ldapoptions *lo )
 235 {
 236         tlsg_ctx *ctx;
 237
 238         ctx = ber_memcalloc ( 1, sizeof (*ctx) );
 239         if ( ctx ) {
 240                 ctx->lo = lo;
 241                 if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
 242                         ber_memfree( ctx );
 243                         return NULL;
 244                 }
 245                 ctx->refcount = 1;
 246 #ifdef HAVE_CIPHERSUITES
 247                 gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
 248 #endif
 249 #ifdef LDAP_R_COMPILE
 250                 ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
 251 #endif
 252         }
 253         return (tls_ctx *)ctx;
 254 }
 255
 256 static void
 257 tlsg_ctx_ref( tls_ctx *ctx )
 258 {
 259         tlsg_ctx *c = (tlsg_ctx *)ctx;
 260 #ifdef LDAP_R_COMPILE
 261         ldap_pvt_thread_mutex_lock( &c->ref_mutex );
 262 #endif
 263         c->refcount++;
 264 #ifdef LDAP_R_COMPILE
 265         ldap_pvt_thread_mutex_unlock( &c->ref_mutex );
 266 #endif
 267 }
 268
 269 static void
 270 tlsg_ctx_free ( tls_ctx *ctx )
 271 {
 272         tlsg_ctx *c = (tlsg_ctx *)ctx;
 273         int refcount;
 274
 275         if ( !c ) return;
 276
 277 #ifdef LDAP_R_COMPILE
 278         ldap_pvt_thread_mutex_lock( &c->ref_mutex );
 279 #endif
 280         refcount = --c->refcount;
 281 #ifdef LDAP_R_COMPILE
 282         ldap_pvt_thread_mutex_unlock( &c->ref_mutex );
 283 #endif
 284         if ( refcount )
 285                 return;
 286 #ifdef HAVE_CIPHERSUITES
 287         gnutls_priority_deinit( c->prios );
 288 #else
 289         LDAP_FREE( c->kx_list );
 290 #endif
 291         gnutls_certificate_free_credentials( c->cred );
 292         ber_memfree ( c );
 293 }
 294
 295 static int
 296 tlsg_getfile( const char *path, gnutls_datum_t *buf )
 297 {
 298         int rc = -1, fd;
 299         struct stat st;
 300
 301         fd = open( path, O_RDONLY );
 302         if ( fd >= 0 && fstat( fd, &st ) == 0 ) {
 303                 buf->size = st.st_size;
 304                 buf->data = LDAP_MALLOC( st.st_size + 1 );
 305                 if ( buf->data ) {
 306                         rc = read( fd, buf->data, st.st_size );
 307                         close( fd );
 308                         if ( rc < st.st_size )
 309                                 rc = -1;
 310                         else
 311                                 rc = 0;
 312                 }
 313         }
 314         return rc;
 315 }
 316
 317 /* This is the GnuTLS default */
 318 #define VERIFY_DEPTH    6
 319
 320 /*
 321  * initialize a new TLS context
 322  */
 323 static int
 324 tlsg_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
 325 {
 326         tlsg_ctx *ctx = lo->ldo_tls_ctx;
 327         int rc;
 328
 329         if ( lo->ldo_tls_ciphersuite &&
 330                 tlsg_parse_ciphers( ctx, lt->lt_ciphersuite )) {
 331                 Debug( LDAP_DEBUG_ANY,
 332                            "TLS: could not set cipher list %s.\n",
 333                            lo->ldo_tls_ciphersuite, 0, 0 );
 334                 return -1;
 335         }
 336
 337         if (lo->ldo_tls_cacertdir != NULL) {
 338                 Debug( LDAP_DEBUG_ANY,
 339                        "TLS: warning: cacertdir not implemented for gnutls\n",
 340                        NULL, NULL, NULL );
 341         }
 342
 343         if (lo->ldo_tls_cacertfile != NULL) {
 344                 rc = gnutls_certificate_set_x509_trust_file(
 345                         ctx->cred,
 346                         lt->lt_cacertfile,
 347                         GNUTLS_X509_FMT_PEM );
 348                 if ( rc < 0 ) return -1;
 349         }
 350
 351         if ( lo->ldo_tls_certfile && lo->ldo_tls_keyfile ) {
 352                 gnutls_x509_privkey_t key;
 353                 gnutls_datum_t buf;
 354                 gnutls_x509_crt_t certs[VERIFY_DEPTH];
 355                 unsigned int max = VERIFY_DEPTH;
 356
 357                 rc = gnutls_x509_privkey_init( &key );
 358                 if ( rc ) return -1;
 359
 360                 /* OpenSSL builds the cert chain for us, but GnuTLS
 361                  * expects it to be present in the certfile. If it's
 362                  * not, we have to build it ourselves. So we have to
 363                  * do some special checks here...
 364                  */
 365                 rc = tlsg_getfile( lt->lt_keyfile, &buf );
 366                 if ( rc ) return -1;
 367                 rc = gnutls_x509_privkey_import( key, &buf,
 368                         GNUTLS_X509_FMT_PEM );
 369                 LDAP_FREE( buf.data );
 370                 if ( rc < 0 ) return rc;
 371
 372                 rc = tlsg_getfile( lt->lt_certfile, &buf );
 373                 if ( rc ) return -1;
 374                 rc = gnutls_x509_crt_list_import( certs, &max, &buf,
 375                         GNUTLS_X509_FMT_PEM, 0 );
 376                 LDAP_FREE( buf.data );
 377                 if ( rc < 0 ) return rc;
 378
 379                 /* If there's only one cert and it's not self-signed,
 380                  * then we have to build the cert chain.
 381                  */
 382                 if ( max == 1 && !gnutls_x509_crt_check_issuer( certs[0], certs[0] )) {
 383                         gnutls_x509_crt_t *cas;
 384                         unsigned int i, j, ncas;
 385
 386                         gnutls_certificate_get_x509_cas( ctx->cred, &cas, &ncas );
 387                         for ( i = 1; i<VERIFY_DEPTH; i++ ) {
 388                                 for ( j = 0; j<ncas; j++ ) {
 389                                         if ( gnutls_x509_crt_check_issuer( certs[i-1], cas[j] )) {
 390                                                 certs[i] = cas[j];
 391                                                 max++;
 392                                                 /* If this CA is self-signed, we're done */
 393                                                 if ( gnutls_x509_crt_check_issuer( cas[j], cas[j] ))
 394                                                         j = ncas;
 395                                                 break;
 396                                         }
 397                                 }
 398                                 /* only continue if we found a CA and it was not self-signed */
 399                                 if ( j == ncas )
 400                                         break;
 401                         }
 402                 }
 403                 rc = gnutls_certificate_set_x509_key( ctx->cred, certs, max, key );
 404                 if ( rc ) return -1;
 405         } else if ( lo->ldo_tls_certfile || lo->ldo_tls_keyfile ) {
 406                 Debug( LDAP_DEBUG_ANY,
 407                        "TLS: only one of certfile and keyfile specified\n",
 408                        NULL, NULL, NULL );
 409                 return -1;
 410         }
 411
 412         if ( lo->ldo_tls_dhfile ) {
 413                 Debug( LDAP_DEBUG_ANY,
 414                        "TLS: warning: ignoring dhfile\n",
 415                        NULL, NULL, NULL );
 416         }
 417
 418         if ( lo->ldo_tls_crlfile ) {
 419                 rc = gnutls_certificate_set_x509_crl_file(
 420                         ctx->cred,
 421                         lt->lt_crlfile,
 422                         GNUTLS_X509_FMT_PEM );
 423                 if ( rc < 0 ) return -1;
 424                 rc = 0;
 425         }
 426
 427         /* FIXME: ITS#5992 - this should go be configurable,
 428          * and V1 CA certs should be phased out ASAP.
 429          */
 430         gnutls_certificate_set_verify_flags( ctx->cred,
 431                 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
 432
 433         if ( is_server ) {
 434                 gnutls_dh_params_init(&ctx->dh_params);
 435                 gnutls_dh_params_generate2(ctx->dh_params, DH_BITS);
 436         }
 437         return 0;
 438 }
 439
 440 static tls_session *
 441 tlsg_session_new ( tls_ctx * ctx, int is_server )
 442 {
 443         tlsg_ctx *c = (tlsg_ctx *)ctx;
 444         tlsg_session *session;
 445
 446         session = ber_memcalloc ( 1, sizeof (*session) );
 447         if ( !session )
 448                 return NULL;
 449
 450         session->ctx = c;
 451         gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
 452 #ifdef HAVE_CIPHERSUITES
 453         gnutls_priority_set( session->session, c->prios );
 454 #else
 455         gnutls_set_default_priority( session->session );
 456         if ( c->kx_list ) {
 457                 gnutls_kx_set_priority( session->session, c->kx_list );
 458                 gnutls_cipher_set_priority( session->session, c->cipher_list );
 459                 gnutls_mac_set_priority( session->session, c->mac_list );
 460         }
 461 #endif
 462         if ( c->cred )
 463                 gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
 464
 465         if ( is_server ) {
 466                 int flag = 0;
 467                 if ( c->lo->ldo_tls_require_cert ) {
 468                         flag = GNUTLS_CERT_REQUEST;
 469                         if ( c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
 470                                 c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD )
 471                                 flag = GNUTLS_CERT_REQUIRE;
 472                         gnutls_certificate_server_set_request( session->session, flag );
 473                 }
 474         }
 475         return (tls_session *)session;
 476 }
 477
 478 static int
 479 tlsg_session_accept( tls_session *session )
 480 {
 481         tlsg_session *s = (tlsg_session *)session;
 482         int rc;
 483
 484         rc = gnutls_handshake( s->session );
 485         if ( rc == 0 && s->ctx->lo->ldo_tls_require_cert != LDAP_OPT_X_TLS_NEVER ) {
 486                 const gnutls_datum_t *peer_cert_list;
 487                 unsigned int list_size;
 488
 489                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 490                                                 &list_size );
 491                 if ( !peer_cert_list && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_TRY )
 492                         rc = 0;
 493                 else {
 494                         rc = tlsg_cert_verify( s );
 495                         if ( rc && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW )
 496                                 rc = 0;
 497                 }
 498         }
 499         return rc;
 500 }
 501
 502 static int
 503 tlsg_session_connect( LDAP *ld, tls_session *session )
 504 {
 505         return tlsg_session_accept( session);
 506 }
 507
 508 static int
 509 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 510 {
 511         tlsg_session *s = (tlsg_session *)session;
 512
 513         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 514                 return 0;
 515
 516         switch (gnutls_record_get_direction (s->session)) {
 517         case 0:
 518                 sb->sb_trans_needs_read = 1;
 519                 return 1;
 520         case 1:
 521                 sb->sb_trans_needs_write = 1;
 522                 return 1;
 523         }
 524         return 0;
 525 }
 526
 527 static char *
 528 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 529 {
 530         return (char *)gnutls_strerror( rc );
 531 }
 532
 533 static void
 534 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 535 {
 536         BerElementBuffer berbuf;
 537         BerElement *ber = (BerElement *)&berbuf;
 538         ber_tag_t tag;
 539         ber_len_t len;
 540         ber_int_t i;
 541
 542         ber_init2( ber, cert, LBER_USE_DER );
 543         tag = ber_skip_tag( ber, &len );        /* Sequence */
 544         tag = ber_skip_tag( ber, &len );        /* Sequence */
 545         tag = ber_skip_tag( ber, &len );        /* Context + Constructed (version) */
 546         if ( tag == 0xa0 )      /* Version is optional */
 547                 tag = ber_get_int( ber, &i );   /* Int: Version */
 548         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 549         ber_skip_data( ber, len );
 550         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 551         ber_skip_data( ber, len );
 552         if ( !get_subject ) {
 553                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 554         } else {
 555                 tag = ber_skip_tag( ber, &len );
 556                 ber_skip_data( ber, len );
 557                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 558                 ber_skip_data( ber, len );
 559                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 560         }
 561         len = ber_ptrlen( ber );
 562         dn->bv_val = cert->bv_val + len;
 563         dn->bv_len = cert->bv_len - len;
 564 }
 565
 566 static int
 567 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 568 {
 569         tlsg_session *s = (tlsg_session *)session;
 570         const gnutls_datum_t *x;
 571         struct berval bv;
 572
 573         x = gnutls_certificate_get_ours( s->session );
 574
 575         if (!x) return LDAP_INVALID_CREDENTIALS;
 576
 577         bv.bv_val = (char *) x->data;
 578         bv.bv_len = x->size;
 579
 580         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 581         return 0;
 582 }
 583
 584 static int
 585 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 586 {
 587         tlsg_session *s = (tlsg_session *)session;
 588         if ( !s->peer_der_dn.bv_val ) {
 589                 const gnutls_datum_t *peer_cert_list;
 590                 unsigned int list_size;
 591                 struct berval bv;
 592
 593                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 594                                                         &list_size );
 595                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 596
 597                 bv.bv_len = peer_cert_list->size;
 598                 bv.bv_val = (char *) peer_cert_list->data;
 599
 600                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 601         }
 602         *der_dn = s->peer_der_dn;
 603         return 0;
 604 }
 605
 606 /* what kind of hostname were we given? */
 607 #define IS_DNS  0
 608 #define IS_IP4  1
 609 #define IS_IP6  2
 610
 611 #define CN_OID  "2.5.4.3"
 612
 613 static int
 614 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 615 {
 616         tlsg_session *s = (tlsg_session *)session;
 617         int i, ret;
 618         const gnutls_datum_t *peer_cert_list;
 619         unsigned int list_size;
 620         char altname[NI_MAXHOST];
 621         size_t altnamesize;
 622
 623         gnutls_x509_crt_t cert;
 624         const char *name;
 625         char *ptr;
 626         char *domain = NULL;
 627 #ifdef LDAP_PF_INET6
 628         struct in6_addr addr;
 629 #else
 630         struct in_addr addr;
 631 #endif
 632         int len1 = 0, len2 = 0;
 633         int ntype = IS_DNS;
 634
 635         if( ldap_int_hostname &&
 636                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 637         {
 638                 name = ldap_int_hostname;
 639         } else {
 640                 name = name_in;
 641         }
 642
 643         peer_cert_list = gnutls_certificate_get_peers( s->session,
 644                                                 &list_size );
 645         if ( !peer_cert_list ) {
 646                 Debug( LDAP_DEBUG_ANY,
 647                         "TLS: unable to get peer certificate.\n",
 648                         0, 0, 0 );
 649                 /* If this was a fatal condition, things would have
 650                  * aborted long before now.
 651                  */
 652                 return LDAP_SUCCESS;
 653         }
 654         ret = gnutls_x509_crt_init( &cert );
 655         if ( ret < 0 )
 656                 return LDAP_LOCAL_ERROR;
 657         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 658         if ( ret ) {
 659                 gnutls_x509_crt_deinit( cert );
 660                 return LDAP_LOCAL_ERROR;
 661         }
 662
 663 #ifdef LDAP_PF_INET6
 664         if (name[0] == '[' && strchr(name, ']')) {
 665                 char *n2 = ldap_strdup(name+1);
 666                 *strchr(n2, ']') = 0;
 667                 if (inet_pton(AF_INET6, n2, &addr))
 668                         ntype = IS_IP6;
 669                 LDAP_FREE(n2);
 670         } else
 671 #endif
 672         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 673                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 674         }
 675
 676         if (ntype == IS_DNS) {
 677                 len1 = strlen(name);
 678                 domain = strchr(name, '.');
 679                 if (domain) {
 680                         len2 = len1 - (domain-name);
 681                 }
 682         }
 683
 684         for ( i=0, ret=0; ret >= 0; i++ ) {
 685                 altnamesize = sizeof(altname);
 686                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 687                         altname, &altnamesize, NULL );
 688                 if ( ret < 0 ) break;
 689
 690                 /* ignore empty */
 691                 if ( altnamesize == 0 ) continue;
 692
 693                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 694                         if (ntype != IS_DNS) continue;
 695
 696                         /* Is this an exact match? */
 697                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 698                                 break;
 699                         }
 700
 701                         /* Is this a wildcard match? */
 702                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 703                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 704                         {
 705                                 break;
 706                         }
 707                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 708                         if (ntype == IS_DNS) continue;
 709
 710 #ifdef LDAP_PF_INET6
 711                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 712                                 continue;
 713                         } else
 714 #endif
 715                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 716                                 continue;
 717                         }
 718                         if (!memcmp(altname, &addr, altnamesize)) {
 719                                 break;
 720                         }
 721                 }
 722         }
 723         if ( ret >= 0 ) {
 724                 ret = LDAP_SUCCESS;
 725         } else {
 726                 /* find the last CN */
 727                 i=0;
 728                 do {
 729                         altnamesize = 0;
 730                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 731                                 i, 1, altname, &altnamesize );
 732                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 733                                 i++;
 734                         else
 735                                 break;
 736                 } while ( 1 );
 737
 738                 if ( i ) {
 739                         altnamesize = sizeof(altname);
 740                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 741                                 i-1, 0, altname, &altnamesize );
 742                 }
 743
 744                 if ( ret < 0 ) {
 745                         Debug( LDAP_DEBUG_ANY,
 746                                 "TLS: unable to get common name from peer certificate.\n",
 747                                 0, 0, 0 );
 748                         ret = LDAP_CONNECT_ERROR;
 749                         if ( ld->ld_error ) {
 750                                 LDAP_FREE( ld->ld_error );
 751                         }
 752                         ld->ld_error = LDAP_STRDUP(
 753                                 _("TLS: unable to get CN from peer certificate"));
 754
 755                 } else {
 756                         ret = LDAP_LOCAL_ERROR;
 757                         if ( !len1 ) len1 = strlen( name );
 758                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 759                                 ret = LDAP_SUCCESS;
 760
 761                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 762                                         /* Is this a wildcard match? */
 763                                 if( domain &&
 764                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 765                                         ret = LDAP_SUCCESS;
 766                                 }
 767                         }
 768                 }
 769
 770                 if( ret == LDAP_LOCAL_ERROR ) {
 771                         altname[altnamesize] = '\0';
 772                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 773                                 "common name in certificate (%s).\n",
 774                                 name, altname, 0 );
 775                         ret = LDAP_CONNECT_ERROR;
 776                         if ( ld->ld_error ) {
 777                                 LDAP_FREE( ld->ld_error );
 778                         }
 779                         ld->ld_error = LDAP_STRDUP(
 780                                 _("TLS: hostname does not match CN in peer certificate"));
 781                 }
 782         }
 783         gnutls_x509_crt_deinit( cert );
 784         return ret;
 785 }
 786
 787 static int
 788 tlsg_session_strength( tls_session *session )
 789 {
 790         tlsg_session *s = (tlsg_session *)session;
 791         gnutls_cipher_algorithm_t c;
 792
 793         c = gnutls_cipher_get( s->session );
 794         return gnutls_cipher_get_key_size( c ) * 8;
 795 }
 796
 797 /* suites is a string of colon-separated cipher suite names. */
 798 static int
 799 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 800 {
 801 #ifdef HAVE_CIPHERSUITES
 802         const char *err;
 803         return gnutls_priority_init( &ctx->prios, suites, &err );
 804 #else
 805         char *ptr, *end;
 806         int i, j, len, num;
 807         int *list, nkx = 0, ncipher = 0, nmac = 0;
 808         int *kx, *cipher, *mac;
 809
 810         num = 0;
 811         ptr = suites;
 812         do {
 813                 end = strchr(ptr, ':');
 814                 if ( end )
 815                         len = end - ptr;
 816                 else
 817                         len = strlen(ptr);
 818                 for (i=0; i<tlsg_n_ciphers; i++) {
 819                         if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
 820                                 num++;
 821                                 break;
 822                         }
 823                 }
 824                 if ( i == tlsg_n_ciphers ) {
 825                         /* unrecognized cipher suite */
 826                         return -1;
 827                 }
 828                 ptr += len + 1;
 829         } while (end);
 830
 831         /* Space for all 3 lists */
 832         list = LDAP_MALLOC( (num+1) * sizeof(int) * 3 );
 833         if ( !list )
 834                 return -1;
 835         kx = list;
 836         cipher = kx+num+1;
 837         mac = cipher+num+1;
 838
 839         ptr = suites;
 840         do {
 841                 end = strchr(ptr, ':');
 842                 if ( end )
 843                         len = end - ptr;
 844                 else
 845                         len = strlen(ptr);
 846                 for (i=0; i<tlsg_n_ciphers; i++) {
 847                         /* For each cipher suite, insert its algorithms into
 848                          * their respective priority lists. Make sure they
 849                          * only appear once in each list.
 850                          */
 851                         if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
 852                                 for (j=0; j<nkx; j++)
 853                                         if ( kx[j] == tlsg_ciphers[i].kx )
 854                                                 break;
 855                                 if ( j == nkx )
 856                                         kx[nkx++] = tlsg_ciphers[i].kx;
 857                                 for (j=0; j<ncipher; j++)
 858                                         if ( cipher[j] == tlsg_ciphers[i].cipher )
 859                                                 break;
 860                                 if ( j == ncipher )
 861                                         cipher[ncipher++] = tlsg_ciphers[i].cipher;
 862                                 for (j=0; j<nmac; j++)
 863                                         if ( mac[j] == tlsg_ciphers[i].mac )
 864                                                 break;
 865                                 if ( j == nmac )
 866                                         mac[nmac++] = tlsg_ciphers[i].mac;
 867                                 break;
 868                         }
 869                 }
 870                 ptr += len + 1;
 871         } while (end);
 872         kx[nkx] = 0;
 873         cipher[ncipher] = 0;
 874         mac[nmac] = 0;
 875         ctx->kx_list = kx;
 876         ctx->cipher_list = cipher;
 877         ctx->mac_list = mac;
 878         return 0;
 879 #endif
 880 }
 881
 882 /*
 883  * TLS support for LBER Sockbufs
 884  */
 885
 886 struct tls_data {
 887         tlsg_session            *session;
 888         Sockbuf_IO_Desc         *sbiod;
 889 };
 890
 891 static ssize_t
 892 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 893 {
 894         struct tls_data         *p;
 895
 896         if ( buf == NULL || len <= 0 ) return 0;
 897
 898         p = (struct tls_data *)ptr;
 899
 900         if ( p == NULL || p->sbiod == NULL ) {
 901                 return 0;
 902         }
 903
 904         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 905 }
 906
 907 static ssize_t
 908 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 909 {
 910         struct tls_data         *p;
 911
 912         if ( buf == NULL || len <= 0 ) return 0;
 913
 914         p = (struct tls_data *)ptr;
 915
 916         if ( p == NULL || p->sbiod == NULL ) {
 917                 return 0;
 918         }
 919
 920         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 921 }
 922
 923 static int
 924 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 925 {
 926         struct tls_data         *p;
 927         tlsg_session    *session = arg;
 928
 929         assert( sbiod != NULL );
 930
 931         p = LBER_MALLOC( sizeof( *p ) );
 932         if ( p == NULL ) {
 933                 return -1;
 934         }
 935
 936         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 937         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 938         gnutls_transport_set_push_function( session->session, tlsg_send );
 939         p->session = session;
 940         p->sbiod = sbiod;
 941         sbiod->sbiod_pvt = p;
 942         return 0;
 943 }
 944
 945 static int
 946 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 947 {
 948         struct tls_data         *p;
 949
 950         assert( sbiod != NULL );
 951         assert( sbiod->sbiod_pvt != NULL );
 952
 953         p = (struct tls_data *)sbiod->sbiod_pvt;
 954         gnutls_deinit ( p->session->session );
 955         LBER_FREE( p->session );
 956         LBER_FREE( sbiod->sbiod_pvt );
 957         sbiod->sbiod_pvt = NULL;
 958         return 0;
 959 }
 960
 961 static int
 962 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 963 {
 964         struct tls_data         *p;
 965
 966         assert( sbiod != NULL );
 967         assert( sbiod->sbiod_pvt != NULL );
 968
 969         p = (struct tls_data *)sbiod->sbiod_pvt;
 970         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 971         return 0;
 972 }
 973
 974 static int
 975 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 976 {
 977         struct tls_data         *p;
 978
 979         assert( sbiod != NULL );
 980         assert( sbiod->sbiod_pvt != NULL );
 981
 982         p = (struct tls_data *)sbiod->sbiod_pvt;
 983
 984         if ( opt == LBER_SB_OPT_GET_SSL ) {
 985                 *((tlsg_session **)arg) = p->session;
 986                 return 1;
 987
 988         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 989                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 990                         return 1;
 991                 }
 992         }
 993
 994         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 995 }
 996
 997 static ber_slen_t
 998 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 999 {
1000         struct tls_data         *p;
1001         ber_slen_t              ret;
1002
1003         assert( sbiod != NULL );
1004         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1005
1006         p = (struct tls_data *)sbiod->sbiod_pvt;
1007
1008         ret = gnutls_record_recv ( p->session->session, buf, len );
1009         switch (ret) {
1010         case GNUTLS_E_INTERRUPTED:
1011         case GNUTLS_E_AGAIN:
1012                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
1013                 sock_errset(EWOULDBLOCK);
1014                 ret = 0;
1015                 break;
1016         case GNUTLS_E_REHANDSHAKE:
1017                 for ( ret = gnutls_handshake ( p->session->session );
1018                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
1019                       ret = gnutls_handshake ( p->session->session ) );
1020                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
1021                 ret = 0;
1022                 break;
1023         default:
1024                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
1025         }
1026         return ret;
1027 }
1028
1029 static ber_slen_t
1030 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
1031 {
1032         struct tls_data         *p;
1033         ber_slen_t              ret;
1034
1035         assert( sbiod != NULL );
1036         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1037
1038         p = (struct tls_data *)sbiod->sbiod_pvt;
1039
1040         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
1041
1042         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
1043                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
1044                 sock_errset(EWOULDBLOCK);
1045                 ret = 0;
1046         } else {
1047                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
1048         }
1049         return ret;
1050 }
1051
1052 static Sockbuf_IO tlsg_sbio =
1053 {
1054         tlsg_sb_setup,          /* sbi_setup */
1055         tlsg_sb_remove,         /* sbi_remove */
1056         tlsg_sb_ctrl,           /* sbi_ctrl */
1057         tlsg_sb_read,           /* sbi_read */
1058         tlsg_sb_write,          /* sbi_write */
1059         tlsg_sb_close           /* sbi_close */
1060 };
1061
1062 /* Certs are not automatically varified during the handshake */
1063 static int
1064 tlsg_cert_verify( tlsg_session *ssl )
1065 {
1066         unsigned int status = 0;
1067         int err;
1068         time_t now = time(0);
1069         time_t peertime;
1070
1071         err = gnutls_certificate_verify_peers2( ssl->session, &status );
1072         if ( err < 0 ) {
1073                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
1074                         err,0,0 );
1075                 return -1;
1076         }
1077         if ( status ) {
1078                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
1079                         status, 0,0 );
1080                 return -1;
1081         }
1082         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
1083         if ( peertime == (time_t) -1 ) {
1084                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
1085                         0, 0, 0 );
1086                 return -1;
1087         }
1088         if ( peertime < now ) {
1089                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
1090                         0, 0, 0 );
1091                 return -1;
1092         }
1093         peertime = gnutls_certificate_activation_time_peers( ssl->session );
1094         if ( peertime == (time_t) -1 ) {
1095                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
1096                         0, 0, 0 );
1097                 return -1;
1098         }
1099         if ( peertime > now ) {
1100                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
1101                         0, 0, 0 );
1102                 return -1;
1103         }
1104         return 0;
1105 }
1106
1107 tls_impl ldap_int_tls_impl = {
1108         "GnuTLS",
1109
1110         tlsg_init,
1111         tlsg_destroy,
1112
1113         tlsg_ctx_new,
1114         tlsg_ctx_ref,
1115         tlsg_ctx_free,
1116         tlsg_ctx_init,
1117
1118         tlsg_session_new,
1119         tlsg_session_connect,
1120         tlsg_session_accept,
1121         tlsg_session_upflags,
1122         tlsg_session_errmsg,
1123         tlsg_session_my_dn,
1124         tlsg_session_peer_dn,
1125         tlsg_session_chkhost,
1126         tlsg_session_strength,
1127
1128         &tlsg_sbio,
1129
1130 #ifdef LDAP_R_COMPILE
1131         tlsg_thr_init,
1132 #else
1133         NULL,
1134 #endif
1135
1136         0
1137 };
1138
1139 #endif /* HAVE_GNUTLS */