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 2008-2017 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         rc = gnutls_handshake( s->session );
 362         if ( rc == 0 && s->ctx->reqcert != LDAP_OPT_X_TLS_NEVER ) {
 363                 const gnutls_datum_t *peer_cert_list;
 364                 unsigned int list_size;
 365
 366                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 367                                                 &list_size );
 368                 if ( !peer_cert_list && s->ctx->reqcert == LDAP_OPT_X_TLS_TRY )
 369                         rc = 0;
 370                 else {
 371                         rc = tlsg_cert_verify( s );
 372                         if ( rc && s->ctx->reqcert == LDAP_OPT_X_TLS_ALLOW )
 373                                 rc = 0;
 374                 }
 375         }
 376         return rc;
 377 }
 378
 379 static int
 380 tlsg_session_connect( LDAP *ld, tls_session *session )
 381 {
 382         return tlsg_session_accept( session);
 383 }
 384
 385 static int
 386 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 387 {
 388         tlsg_session *s = (tlsg_session *)session;
 389
 390         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 391                 return 0;
 392
 393         switch (gnutls_record_get_direction (s->session)) {
 394         case 0:
 395                 sb->sb_trans_needs_read = 1;
 396                 return 1;
 397         case 1:
 398                 sb->sb_trans_needs_write = 1;
 399                 return 1;
 400         }
 401         return 0;
 402 }
 403
 404 static char *
 405 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 406 {
 407         return (char *)gnutls_strerror( rc );
 408 }
 409
 410 static void
 411 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 412 {
 413         BerElementBuffer berbuf;
 414         BerElement *ber = (BerElement *)&berbuf;
 415         ber_tag_t tag;
 416         ber_len_t len;
 417         ber_int_t i;
 418
 419         ber_init2( ber, cert, LBER_USE_DER );
 420         tag = ber_skip_tag( ber, &len );        /* Sequence */
 421         tag = ber_skip_tag( ber, &len );        /* Sequence */
 422         tag = ber_peek_tag( ber, &len );        /* Context + Constructed (version) */
 423         if ( tag == 0xa0 ) {    /* Version is optional */
 424                 tag = ber_skip_tag( ber, &len );
 425                 tag = ber_get_int( ber, &i );   /* Int: Version */
 426         }
 427         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 428         ber_skip_data( ber, len );
 429         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 430         ber_skip_data( ber, len );
 431         if ( !get_subject ) {
 432                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 433         } else {
 434                 tag = ber_skip_tag( ber, &len );
 435                 ber_skip_data( ber, len );
 436                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 437                 ber_skip_data( ber, len );
 438                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 439         }
 440         len = ber_ptrlen( ber );
 441         dn->bv_val = cert->bv_val + len;
 442         dn->bv_len = cert->bv_len - len;
 443 }
 444
 445 static int
 446 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 447 {
 448         tlsg_session *s = (tlsg_session *)session;
 449         const gnutls_datum_t *x;
 450         struct berval bv;
 451
 452         x = gnutls_certificate_get_ours( s->session );
 453
 454         if (!x) return LDAP_INVALID_CREDENTIALS;
 455
 456         bv.bv_val = (char *) x->data;
 457         bv.bv_len = x->size;
 458
 459         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 460         return 0;
 461 }
 462
 463 static int
 464 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 465 {
 466         tlsg_session *s = (tlsg_session *)session;
 467         if ( !s->peer_der_dn.bv_val ) {
 468                 const gnutls_datum_t *peer_cert_list;
 469                 unsigned int list_size;
 470                 struct berval bv;
 471
 472                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 473                                                         &list_size );
 474                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 475
 476                 bv.bv_len = peer_cert_list->size;
 477                 bv.bv_val = (char *) peer_cert_list->data;
 478
 479                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 480         }
 481         *der_dn = s->peer_der_dn;
 482         return 0;
 483 }
 484
 485 /* what kind of hostname were we given? */
 486 #define IS_DNS  0
 487 #define IS_IP4  1
 488 #define IS_IP6  2
 489
 490 #define CN_OID  "2.5.4.3"
 491
 492 static int
 493 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 494 {
 495         tlsg_session *s = (tlsg_session *)session;
 496         int i, ret;
 497         const gnutls_datum_t *peer_cert_list;
 498         unsigned int list_size;
 499         char altname[NI_MAXHOST];
 500         size_t altnamesize;
 501
 502         gnutls_x509_crt_t cert;
 503         const char *name;
 504         char *ptr;
 505         char *domain = NULL;
 506 #ifdef LDAP_PF_INET6
 507         struct in6_addr addr;
 508 #else
 509         struct in_addr addr;
 510 #endif
 511         int len1 = 0, len2 = 0;
 512         int ntype = IS_DNS;
 513
 514         if( ldap_int_hostname &&
 515                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 516         {
 517                 name = ldap_int_hostname;
 518         } else {
 519                 name = name_in;
 520         }
 521
 522         peer_cert_list = gnutls_certificate_get_peers( s->session,
 523                                                 &list_size );
 524         if ( !peer_cert_list ) {
 525                 Debug( LDAP_DEBUG_ANY,
 526                         "TLS: unable to get peer certificate.\n",
 527                         0, 0, 0 );
 528                 /* If this was a fatal condition, things would have
 529                  * aborted long before now.
 530                  */
 531                 return LDAP_SUCCESS;
 532         }
 533         ret = gnutls_x509_crt_init( &cert );
 534         if ( ret < 0 )
 535                 return LDAP_LOCAL_ERROR;
 536         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 537         if ( ret ) {
 538                 gnutls_x509_crt_deinit( cert );
 539                 return LDAP_LOCAL_ERROR;
 540         }
 541
 542 #ifdef LDAP_PF_INET6
 543         if (inet_pton(AF_INET6, name, &addr)) {
 544                 ntype = IS_IP6;
 545         } else
 546 #endif
 547         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 548                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 549         }
 550
 551         if (ntype == IS_DNS) {
 552                 len1 = strlen(name);
 553                 domain = strchr(name, '.');
 554                 if (domain) {
 555                         len2 = len1 - (domain-name);
 556                 }
 557         }
 558
 559         for ( i=0, ret=0; ret >= 0; i++ ) {
 560                 altnamesize = sizeof(altname);
 561                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 562                         altname, &altnamesize, NULL );
 563                 if ( ret < 0 ) break;
 564
 565                 /* ignore empty */
 566                 if ( altnamesize == 0 ) continue;
 567
 568                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 569                         if (ntype != IS_DNS) continue;
 570
 571                         /* Is this an exact match? */
 572                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 573                                 break;
 574                         }
 575
 576                         /* Is this a wildcard match? */
 577                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 578                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 579                         {
 580                                 break;
 581                         }
 582                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 583                         if (ntype == IS_DNS) continue;
 584
 585 #ifdef LDAP_PF_INET6
 586                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 587                                 continue;
 588                         } else
 589 #endif
 590                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 591                                 continue;
 592                         }
 593                         if (!memcmp(altname, &addr, altnamesize)) {
 594                                 break;
 595                         }
 596                 }
 597         }
 598         if ( ret >= 0 ) {
 599                 ret = LDAP_SUCCESS;
 600         } else {
 601                 /* find the last CN */
 602                 i=0;
 603                 do {
 604                         altnamesize = 0;
 605                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 606                                 i, 1, altname, &altnamesize );
 607                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 608                                 i++;
 609                         else
 610                                 break;
 611                 } while ( 1 );
 612
 613                 if ( i ) {
 614                         altnamesize = sizeof(altname);
 615                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 616                                 i-1, 0, altname, &altnamesize );
 617                 }
 618
 619                 if ( ret < 0 ) {
 620                         Debug( LDAP_DEBUG_ANY,
 621                                 "TLS: unable to get common name from peer certificate.\n",
 622                                 0, 0, 0 );
 623                         ret = LDAP_CONNECT_ERROR;
 624                         if ( ld->ld_error ) {
 625                                 LDAP_FREE( ld->ld_error );
 626                         }
 627                         ld->ld_error = LDAP_STRDUP(
 628                                 _("TLS: unable to get CN from peer certificate"));
 629
 630                 } else {
 631                         ret = LDAP_LOCAL_ERROR;
 632                         if ( !len1 ) len1 = strlen( name );
 633                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 634                                 ret = LDAP_SUCCESS;
 635
 636                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 637                                         /* Is this a wildcard match? */
 638                                 if( domain &&
 639                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 640                                         ret = LDAP_SUCCESS;
 641                                 }
 642                         }
 643                 }
 644
 645                 if( ret == LDAP_LOCAL_ERROR ) {
 646                         altname[altnamesize] = '\0';
 647                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 648                                 "common name in certificate (%s).\n",
 649                                 name, altname, 0 );
 650                         ret = LDAP_CONNECT_ERROR;
 651                         if ( ld->ld_error ) {
 652                                 LDAP_FREE( ld->ld_error );
 653                         }
 654                         ld->ld_error = LDAP_STRDUP(
 655                                 _("TLS: hostname does not match CN in peer certificate"));
 656                 }
 657         }
 658         gnutls_x509_crt_deinit( cert );
 659         return ret;
 660 }
 661
 662 static int
 663 tlsg_session_strength( tls_session *session )
 664 {
 665         tlsg_session *s = (tlsg_session *)session;
 666         gnutls_cipher_algorithm_t c;
 667
 668         c = gnutls_cipher_get( s->session );
 669         return gnutls_cipher_get_key_size( c ) * 8;
 670 }
 671
 672 static int
 673 tlsg_session_unique( tls_session *sess, struct berval *buf, int is_server)
 674 {
 675         tlsg_session *s = (tlsg_session *)sess;
 676         gnutls_datum_t cb;
 677         int rc;
 678
 679         rc = gnutls_session_channel_binding( s->session, GNUTLS_CB_TLS_UNIQUE, &cb );
 680         if ( rc == 0 ) {
 681                 int len = cb.size;
 682                 if ( len > buf->bv_len )
 683                         len = buf->bv_len;
 684                 buf->bv_len = len;
 685                 memcpy( buf->bv_val, cb.data, len );
 686                 return len;
 687         }
 688         return 0;
 689 }
 690
 691 static const char *
 692 tlsg_session_version( tls_session *sess )
 693 {
 694         tlsg_session *s = (tlsg_session *)sess;
 695         return gnutls_protocol_get_name(gnutls_protocol_get_version( s->session ));
 696 }
 697
 698 static const char *
 699 tlsg_session_cipher( tls_session *sess )
 700 {
 701         tlsg_session *s = (tlsg_session *)sess;
 702         return gnutls_cipher_get_name(gnutls_cipher_get( s->session ));
 703 }
 704
 705 static int
 706 tlsg_session_peercert( tls_session *sess, struct berval *der )
 707 {
 708         tlsg_session *s = (tlsg_session *)sess;
 709         const gnutls_datum_t *peer_cert_list;
 710         unsigned int list_size;
 711
 712         peer_cert_list = gnutls_certificate_get_peers( s->session, &list_size );
 713         if (!peer_cert_list)
 714                 return -1;
 715         der->bv_len = peer_cert_list[0].size;
 716         der->bv_val = LDAP_MALLOC( der->bv_len );
 717         if (!der->bv_val)
 718                 return -1;
 719         memcpy(der->bv_val, peer_cert_list[0].data, der->bv_len);
 720         return 0;
 721 }
 722
 723 /* suites is a string of colon-separated cipher suite names. */
 724 static int
 725 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 726 {
 727         const char *err;
 728         int rc = gnutls_priority_init( &ctx->prios, suites, &err );
 729         if ( rc )
 730                 ctx->prios = NULL;
 731         return rc;
 732 }
 733
 734 /*
 735  * TLS support for LBER Sockbufs
 736  */
 737
 738 struct tls_data {
 739         tlsg_session            *session;
 740         Sockbuf_IO_Desc         *sbiod;
 741 };
 742
 743 static ssize_t
 744 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 745 {
 746         struct tls_data         *p;
 747
 748         if ( buf == NULL || len <= 0 ) return 0;
 749
 750         p = (struct tls_data *)ptr;
 751
 752         if ( p == NULL || p->sbiod == NULL ) {
 753                 return 0;
 754         }
 755
 756         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 757 }
 758
 759 static ssize_t
 760 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 761 {
 762         struct tls_data         *p;
 763
 764         if ( buf == NULL || len <= 0 ) return 0;
 765
 766         p = (struct tls_data *)ptr;
 767
 768         if ( p == NULL || p->sbiod == NULL ) {
 769                 return 0;
 770         }
 771
 772         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 773 }
 774
 775 static int
 776 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 777 {
 778         struct tls_data         *p;
 779         tlsg_session    *session = arg;
 780
 781         assert( sbiod != NULL );
 782
 783         p = LBER_MALLOC( sizeof( *p ) );
 784         if ( p == NULL ) {
 785                 return -1;
 786         }
 787
 788         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 789         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 790         gnutls_transport_set_push_function( session->session, tlsg_send );
 791         p->session = session;
 792         p->sbiod = sbiod;
 793         sbiod->sbiod_pvt = p;
 794         return 0;
 795 }
 796
 797 static int
 798 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 799 {
 800         struct tls_data         *p;
 801
 802         assert( sbiod != NULL );
 803         assert( sbiod->sbiod_pvt != NULL );
 804
 805         p = (struct tls_data *)sbiod->sbiod_pvt;
 806         gnutls_deinit ( p->session->session );
 807         LBER_FREE( p->session );
 808         LBER_FREE( sbiod->sbiod_pvt );
 809         sbiod->sbiod_pvt = NULL;
 810         return 0;
 811 }
 812
 813 static int
 814 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 815 {
 816         struct tls_data         *p;
 817
 818         assert( sbiod != NULL );
 819         assert( sbiod->sbiod_pvt != NULL );
 820
 821         p = (struct tls_data *)sbiod->sbiod_pvt;
 822         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 823         return 0;
 824 }
 825
 826 static int
 827 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 828 {
 829         struct tls_data         *p;
 830
 831         assert( sbiod != NULL );
 832         assert( sbiod->sbiod_pvt != NULL );
 833
 834         p = (struct tls_data *)sbiod->sbiod_pvt;
 835
 836         if ( opt == LBER_SB_OPT_GET_SSL ) {
 837                 *((tlsg_session **)arg) = p->session;
 838                 return 1;
 839
 840         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 841                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 842                         return 1;
 843                 }
 844         }
 845
 846         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 847 }
 848
 849 static ber_slen_t
 850 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 851 {
 852         struct tls_data         *p;
 853         ber_slen_t              ret;
 854
 855         assert( sbiod != NULL );
 856         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 857
 858         p = (struct tls_data *)sbiod->sbiod_pvt;
 859
 860         ret = gnutls_record_recv ( p->session->session, buf, len );
 861         switch (ret) {
 862         case GNUTLS_E_INTERRUPTED:
 863         case GNUTLS_E_AGAIN:
 864                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 865                 sock_errset(EWOULDBLOCK);
 866                 ret = 0;
 867                 break;
 868         case GNUTLS_E_REHANDSHAKE:
 869                 for ( ret = gnutls_handshake ( p->session->session );
 870                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
 871                       ret = gnutls_handshake ( p->session->session ) );
 872                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 873                 ret = 0;
 874                 break;
 875         default:
 876                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
 877         }
 878         return ret;
 879 }
 880
 881 static ber_slen_t
 882 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 883 {
 884         struct tls_data         *p;
 885         ber_slen_t              ret;
 886
 887         assert( sbiod != NULL );
 888         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 889
 890         p = (struct tls_data *)sbiod->sbiod_pvt;
 891
 892         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
 893
 894         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
 895                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
 896                 sock_errset(EWOULDBLOCK);
 897                 ret = 0;
 898         } else {
 899                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
 900         }
 901         return ret;
 902 }
 903
 904 static Sockbuf_IO tlsg_sbio =
 905 {
 906         tlsg_sb_setup,          /* sbi_setup */
 907         tlsg_sb_remove,         /* sbi_remove */
 908         tlsg_sb_ctrl,           /* sbi_ctrl */
 909         tlsg_sb_read,           /* sbi_read */
 910         tlsg_sb_write,          /* sbi_write */
 911         tlsg_sb_close           /* sbi_close */
 912 };
 913
 914 /* Certs are not automatically varified during the handshake */
 915 static int
 916 tlsg_cert_verify( tlsg_session *ssl )
 917 {
 918         unsigned int status = 0;
 919         int err;
 920         time_t now = time(0);
 921         time_t peertime;
 922
 923         err = gnutls_certificate_verify_peers2( ssl->session, &status );
 924         if ( err < 0 ) {
 925                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
 926                         err,0,0 );
 927                 return -1;
 928         }
 929         if ( status ) {
 930                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
 931                         status, 0,0 );
 932                 return -1;
 933         }
 934         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
 935         if ( peertime == (time_t) -1 ) {
 936                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
 937                         0, 0, 0 );
 938                 return -1;
 939         }
 940         if ( peertime < now ) {
 941                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
 942                         0, 0, 0 );
 943                 return -1;
 944         }
 945         peertime = gnutls_certificate_activation_time_peers( ssl->session );
 946         if ( peertime == (time_t) -1 ) {
 947                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
 948                         0, 0, 0 );
 949                 return -1;
 950         }
 951         if ( peertime > now ) {
 952                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
 953                         0, 0, 0 );
 954                 return -1;
 955         }
 956         return 0;
 957 }
 958
 959 tls_impl ldap_int_tls_impl = {
 960         "GnuTLS",
 961
 962         tlsg_init,
 963         tlsg_destroy,
 964
 965         tlsg_ctx_new,
 966         tlsg_ctx_ref,
 967         tlsg_ctx_free,
 968         tlsg_ctx_init,
 969
 970         tlsg_session_new,
 971         tlsg_session_connect,
 972         tlsg_session_accept,
 973         tlsg_session_upflags,
 974         tlsg_session_errmsg,
 975         tlsg_session_my_dn,
 976         tlsg_session_peer_dn,
 977         tlsg_session_chkhost,
 978         tlsg_session_strength,
 979         tlsg_session_unique,
 980         tlsg_session_version,
 981         tlsg_session_cipher,
 982         tlsg_session_peercert,
 983
 984         &tlsg_sbio,
 985
 986 #ifdef LDAP_R_COMPILE
 987         tlsg_thr_init,
 988 #else
 989         NULL,
 990 #endif
 991
 992         0
 993 };
 994
 995 #endif /* HAVE_GNUTLS */