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 2008-2016 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         struct ldapoptions *lo;
  49         gnutls_certificate_credentials_t cred;
  50         gnutls_dh_params_t dh_params;
  51         unsigned long verify_depth;
  52         int refcount;
  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                 ctx->lo = lo;
 145                 if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
 146                         ber_memfree( ctx );
 147                         return NULL;
 148                 }
 149                 ctx->refcount = 1;
 150                 gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
 151 #ifdef LDAP_R_COMPILE
 152                 ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
 153 #endif
 154         }
 155         return (tls_ctx *)ctx;
 156 }
 157
 158 static void
 159 tlsg_ctx_ref( tls_ctx *ctx )
 160 {
 161         tlsg_ctx *c = (tlsg_ctx *)ctx;
 162         LDAP_MUTEX_LOCK( &c->ref_mutex );
 163         c->refcount++;
 164         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 165 }
 166
 167 static void
 168 tlsg_ctx_free ( tls_ctx *ctx )
 169 {
 170         tlsg_ctx *c = (tlsg_ctx *)ctx;
 171         int refcount;
 172
 173         if ( !c ) return;
 174
 175         LDAP_MUTEX_LOCK( &c->ref_mutex );
 176         refcount = --c->refcount;
 177         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 178         if ( refcount )
 179                 return;
 180         gnutls_priority_deinit( c->prios );
 181         gnutls_certificate_free_credentials( c->cred );
 182         if ( c->dh_params )
 183                 gnutls_dh_params_deinit( c->dh_params );
 184         ber_memfree ( c );
 185 }
 186
 187 static int
 188 tlsg_getfile( const char *path, gnutls_datum_t *buf )
 189 {
 190         int rc = -1, fd;
 191         struct stat st;
 192
 193         fd = open( path, O_RDONLY );
 194         if ( fd >= 0 && fstat( fd, &st ) == 0 ) {
 195                 buf->size = st.st_size;
 196                 buf->data = LDAP_MALLOC( st.st_size + 1 );
 197                 if ( buf->data ) {
 198                         rc = read( fd, buf->data, st.st_size );
 199                         close( fd );
 200                         if ( rc < st.st_size )
 201                                 rc = -1;
 202                         else
 203                                 rc = 0;
 204                 }
 205         }
 206         return rc;
 207 }
 208
 209 /* This is the GnuTLS default */
 210 #define VERIFY_DEPTH    6
 211
 212 /*
 213  * initialize a new TLS context
 214  */
 215 static int
 216 tlsg_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
 217 {
 218         tlsg_ctx *ctx = lo->ldo_tls_ctx;
 219         int rc;
 220
 221         if ( lo->ldo_tls_ciphersuite &&
 222                 tlsg_parse_ciphers( ctx, lt->lt_ciphersuite )) {
 223                 Debug( LDAP_DEBUG_ANY,
 224                            "TLS: could not set cipher list %s.\n",
 225                            lo->ldo_tls_ciphersuite, 0, 0 );
 226                 return -1;
 227         }
 228
 229         if (lo->ldo_tls_cacertdir != NULL) {
 230                 Debug( LDAP_DEBUG_ANY,
 231                        "TLS: warning: cacertdir not implemented for gnutls\n",
 232                        NULL, NULL, NULL );
 233         }
 234
 235         if (lo->ldo_tls_cacertfile != NULL) {
 236                 rc = gnutls_certificate_set_x509_trust_file(
 237                         ctx->cred,
 238                         lt->lt_cacertfile,
 239                         GNUTLS_X509_FMT_PEM );
 240                 if ( rc < 0 ) return -1;
 241         }
 242
 243         if ( lo->ldo_tls_certfile && lo->ldo_tls_keyfile ) {
 244                 gnutls_x509_privkey_t key;
 245                 gnutls_datum_t buf;
 246                 gnutls_x509_crt_t certs[VERIFY_DEPTH];
 247                 unsigned int max = VERIFY_DEPTH;
 248
 249                 rc = gnutls_x509_privkey_init( &key );
 250                 if ( rc ) return -1;
 251
 252                 /* OpenSSL builds the cert chain for us, but GnuTLS
 253                  * expects it to be present in the certfile. If it's
 254                  * not, we have to build it ourselves. So we have to
 255                  * do some special checks here...
 256                  */
 257                 rc = tlsg_getfile( lt->lt_keyfile, &buf );
 258                 if ( rc ) return -1;
 259                 rc = gnutls_x509_privkey_import( key, &buf,
 260                         GNUTLS_X509_FMT_PEM );
 261                 LDAP_FREE( buf.data );
 262                 if ( rc < 0 ) return rc;
 263
 264                 rc = tlsg_getfile( lt->lt_certfile, &buf );
 265                 if ( rc ) return -1;
 266                 rc = gnutls_x509_crt_list_import( certs, &max, &buf,
 267                         GNUTLS_X509_FMT_PEM, 0 );
 268                 LDAP_FREE( buf.data );
 269                 if ( rc < 0 ) return rc;
 270
 271                 /* If there's only one cert and it's not self-signed,
 272                  * then we have to build the cert chain.
 273                  */
 274                 if ( max == 1 && !gnutls_x509_crt_check_issuer( certs[0], certs[0] )) {
 275                         unsigned int i;
 276                         for ( i = 1; i<VERIFY_DEPTH; i++ ) {
 277                                 if ( gnutls_certificate_get_issuer( ctx->cred, certs[i-1], &certs[i], 0 ))
 278                                         break;
 279                                 max++;
 280                                 /* If this CA is self-signed, we're done */
 281                                 if ( gnutls_x509_crt_check_issuer( certs[i], certs[i] ))
 282                                         break;
 283                         }
 284                 }
 285                 rc = gnutls_certificate_set_x509_key( ctx->cred, certs, max, key );
 286                 if ( rc ) return -1;
 287         } else if ( lo->ldo_tls_certfile || lo->ldo_tls_keyfile ) {
 288                 Debug( LDAP_DEBUG_ANY,
 289                        "TLS: only one of certfile and keyfile specified\n",
 290                        NULL, NULL, NULL );
 291                 return -1;
 292         }
 293
 294         if ( lo->ldo_tls_crlfile ) {
 295                 rc = gnutls_certificate_set_x509_crl_file(
 296                         ctx->cred,
 297                         lt->lt_crlfile,
 298                         GNUTLS_X509_FMT_PEM );
 299                 if ( rc < 0 ) return -1;
 300                 rc = 0;
 301         }
 302
 303         /* FIXME: ITS#5992 - this should be configurable,
 304          * and V1 CA certs should be phased out ASAP.
 305          */
 306         gnutls_certificate_set_verify_flags( ctx->cred,
 307                 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
 308
 309         if ( is_server && lo->ldo_tls_dhfile ) {
 310                 gnutls_datum_t buf;
 311                 rc = tlsg_getfile( lo->ldo_tls_dhfile, &buf );
 312                 if ( rc ) return -1;
 313                 rc = gnutls_dh_params_init( &ctx->dh_params );
 314                 if ( rc == 0 )
 315                         rc = gnutls_dh_params_import_pkcs3( ctx->dh_params, &buf,
 316                                 GNUTLS_X509_FMT_PEM );
 317                 LDAP_FREE( buf.data );
 318                 if ( rc ) return -1;
 319                 gnutls_certificate_set_dh_params( ctx->cred, ctx->dh_params );
 320         }
 321         return 0;
 322 }
 323
 324 static tls_session *
 325 tlsg_session_new ( tls_ctx * ctx, int is_server )
 326 {
 327         tlsg_ctx *c = (tlsg_ctx *)ctx;
 328         tlsg_session *session;
 329
 330         session = ber_memcalloc ( 1, sizeof (*session) );
 331         if ( !session )
 332                 return NULL;
 333
 334         session->ctx = c;
 335         gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
 336         gnutls_priority_set( session->session, c->prios );
 337         if ( c->cred )
 338                 gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
 339
 340         if ( is_server ) {
 341                 int flag = 0;
 342                 if ( c->lo->ldo_tls_require_cert ) {
 343                         flag = GNUTLS_CERT_REQUEST;
 344                         if ( c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
 345                                 c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD )
 346                                 flag = GNUTLS_CERT_REQUIRE;
 347                         gnutls_certificate_server_set_request( session->session, flag );
 348                 }
 349         }
 350         return (tls_session *)session;
 351 }
 352
 353 static int
 354 tlsg_session_accept( tls_session *session )
 355 {
 356         tlsg_session *s = (tlsg_session *)session;
 357         int rc;
 358
 359         rc = gnutls_handshake( s->session );
 360         if ( rc == 0 && s->ctx->lo->ldo_tls_require_cert != LDAP_OPT_X_TLS_NEVER ) {
 361                 const gnutls_datum_t *peer_cert_list;
 362                 unsigned int list_size;
 363
 364                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 365                                                 &list_size );
 366                 if ( !peer_cert_list && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_TRY )
 367                         rc = 0;
 368                 else {
 369                         rc = tlsg_cert_verify( s );
 370                         if ( rc && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW )
 371                                 rc = 0;
 372                 }
 373         }
 374         return rc;
 375 }
 376
 377 static int
 378 tlsg_session_connect( LDAP *ld, tls_session *session )
 379 {
 380         return tlsg_session_accept( session);
 381 }
 382
 383 static int
 384 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 385 {
 386         tlsg_session *s = (tlsg_session *)session;
 387
 388         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 389                 return 0;
 390
 391         switch (gnutls_record_get_direction (s->session)) {
 392         case 0:
 393                 sb->sb_trans_needs_read = 1;
 394                 return 1;
 395         case 1:
 396                 sb->sb_trans_needs_write = 1;
 397                 return 1;
 398         }
 399         return 0;
 400 }
 401
 402 static char *
 403 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 404 {
 405         return (char *)gnutls_strerror( rc );
 406 }
 407
 408 static void
 409 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 410 {
 411         BerElementBuffer berbuf;
 412         BerElement *ber = (BerElement *)&berbuf;
 413         ber_tag_t tag;
 414         ber_len_t len;
 415         ber_int_t i;
 416
 417         ber_init2( ber, cert, LBER_USE_DER );
 418         tag = ber_skip_tag( ber, &len );        /* Sequence */
 419         tag = ber_skip_tag( ber, &len );        /* Sequence */
 420         tag = ber_peek_tag( ber, &len );        /* Context + Constructed (version) */
 421         if ( tag == 0xa0 ) {    /* Version is optional */
 422                 tag = ber_skip_tag( ber, &len );
 423                 tag = ber_get_int( ber, &i );   /* Int: Version */
 424         }
 425         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 426         ber_skip_data( ber, len );
 427         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 428         ber_skip_data( ber, len );
 429         if ( !get_subject ) {
 430                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 431         } else {
 432                 tag = ber_skip_tag( ber, &len );
 433                 ber_skip_data( ber, len );
 434                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 435                 ber_skip_data( ber, len );
 436                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 437         }
 438         len = ber_ptrlen( ber );
 439         dn->bv_val = cert->bv_val + len;
 440         dn->bv_len = cert->bv_len - len;
 441 }
 442
 443 static int
 444 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 445 {
 446         tlsg_session *s = (tlsg_session *)session;
 447         const gnutls_datum_t *x;
 448         struct berval bv;
 449
 450         x = gnutls_certificate_get_ours( s->session );
 451
 452         if (!x) return LDAP_INVALID_CREDENTIALS;
 453
 454         bv.bv_val = (char *) x->data;
 455         bv.bv_len = x->size;
 456
 457         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 458         return 0;
 459 }
 460
 461 static int
 462 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 463 {
 464         tlsg_session *s = (tlsg_session *)session;
 465         if ( !s->peer_der_dn.bv_val ) {
 466                 const gnutls_datum_t *peer_cert_list;
 467                 unsigned int list_size;
 468                 struct berval bv;
 469
 470                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 471                                                         &list_size );
 472                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 473
 474                 bv.bv_len = peer_cert_list->size;
 475                 bv.bv_val = (char *) peer_cert_list->data;
 476
 477                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 478         }
 479         *der_dn = s->peer_der_dn;
 480         return 0;
 481 }
 482
 483 /* what kind of hostname were we given? */
 484 #define IS_DNS  0
 485 #define IS_IP4  1
 486 #define IS_IP6  2
 487
 488 #define CN_OID  "2.5.4.3"
 489
 490 static int
 491 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 492 {
 493         tlsg_session *s = (tlsg_session *)session;
 494         int i, ret;
 495         const gnutls_datum_t *peer_cert_list;
 496         unsigned int list_size;
 497         char altname[NI_MAXHOST];
 498         size_t altnamesize;
 499
 500         gnutls_x509_crt_t cert;
 501         const char *name;
 502         char *ptr;
 503         char *domain = NULL;
 504 #ifdef LDAP_PF_INET6
 505         struct in6_addr addr;
 506 #else
 507         struct in_addr addr;
 508 #endif
 509         int len1 = 0, len2 = 0;
 510         int ntype = IS_DNS;
 511
 512         if( ldap_int_hostname &&
 513                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 514         {
 515                 name = ldap_int_hostname;
 516         } else {
 517                 name = name_in;
 518         }
 519
 520         peer_cert_list = gnutls_certificate_get_peers( s->session,
 521                                                 &list_size );
 522         if ( !peer_cert_list ) {
 523                 Debug( LDAP_DEBUG_ANY,
 524                         "TLS: unable to get peer certificate.\n",
 525                         0, 0, 0 );
 526                 /* If this was a fatal condition, things would have
 527                  * aborted long before now.
 528                  */
 529                 return LDAP_SUCCESS;
 530         }
 531         ret = gnutls_x509_crt_init( &cert );
 532         if ( ret < 0 )
 533                 return LDAP_LOCAL_ERROR;
 534         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 535         if ( ret ) {
 536                 gnutls_x509_crt_deinit( cert );
 537                 return LDAP_LOCAL_ERROR;
 538         }
 539
 540 #ifdef LDAP_PF_INET6
 541         if (inet_pton(AF_INET6, name, &addr)) {
 542                 ntype = IS_IP6;
 543         } else
 544 #endif
 545         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 546                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 547         }
 548
 549         if (ntype == IS_DNS) {
 550                 len1 = strlen(name);
 551                 domain = strchr(name, '.');
 552                 if (domain) {
 553                         len2 = len1 - (domain-name);
 554                 }
 555         }
 556
 557         for ( i=0, ret=0; ret >= 0; i++ ) {
 558                 altnamesize = sizeof(altname);
 559                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 560                         altname, &altnamesize, NULL );
 561                 if ( ret < 0 ) break;
 562
 563                 /* ignore empty */
 564                 if ( altnamesize == 0 ) continue;
 565
 566                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 567                         if (ntype != IS_DNS) continue;
 568
 569                         /* Is this an exact match? */
 570                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 571                                 break;
 572                         }
 573
 574                         /* Is this a wildcard match? */
 575                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 576                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 577                         {
 578                                 break;
 579                         }
 580                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 581                         if (ntype == IS_DNS) continue;
 582
 583 #ifdef LDAP_PF_INET6
 584                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 585                                 continue;
 586                         } else
 587 #endif
 588                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 589                                 continue;
 590                         }
 591                         if (!memcmp(altname, &addr, altnamesize)) {
 592                                 break;
 593                         }
 594                 }
 595         }
 596         if ( ret >= 0 ) {
 597                 ret = LDAP_SUCCESS;
 598         } else {
 599                 /* find the last CN */
 600                 i=0;
 601                 do {
 602                         altnamesize = 0;
 603                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 604                                 i, 1, altname, &altnamesize );
 605                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 606                                 i++;
 607                         else
 608                                 break;
 609                 } while ( 1 );
 610
 611                 if ( i ) {
 612                         altnamesize = sizeof(altname);
 613                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 614                                 i-1, 0, altname, &altnamesize );
 615                 }
 616
 617                 if ( ret < 0 ) {
 618                         Debug( LDAP_DEBUG_ANY,
 619                                 "TLS: unable to get common name from peer certificate.\n",
 620                                 0, 0, 0 );
 621                         ret = LDAP_CONNECT_ERROR;
 622                         if ( ld->ld_error ) {
 623                                 LDAP_FREE( ld->ld_error );
 624                         }
 625                         ld->ld_error = LDAP_STRDUP(
 626                                 _("TLS: unable to get CN from peer certificate"));
 627
 628                 } else {
 629                         ret = LDAP_LOCAL_ERROR;
 630                         if ( !len1 ) len1 = strlen( name );
 631                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 632                                 ret = LDAP_SUCCESS;
 633
 634                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 635                                         /* Is this a wildcard match? */
 636                                 if( domain &&
 637                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 638                                         ret = LDAP_SUCCESS;
 639                                 }
 640                         }
 641                 }
 642
 643                 if( ret == LDAP_LOCAL_ERROR ) {
 644                         altname[altnamesize] = '\0';
 645                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 646                                 "common name in certificate (%s).\n",
 647                                 name, altname, 0 );
 648                         ret = LDAP_CONNECT_ERROR;
 649                         if ( ld->ld_error ) {
 650                                 LDAP_FREE( ld->ld_error );
 651                         }
 652                         ld->ld_error = LDAP_STRDUP(
 653                                 _("TLS: hostname does not match CN in peer certificate"));
 654                 }
 655         }
 656         gnutls_x509_crt_deinit( cert );
 657         return ret;
 658 }
 659
 660 static int
 661 tlsg_session_strength( tls_session *session )
 662 {
 663         tlsg_session *s = (tlsg_session *)session;
 664         gnutls_cipher_algorithm_t c;
 665
 666         c = gnutls_cipher_get( s->session );
 667         return gnutls_cipher_get_key_size( c ) * 8;
 668 }
 669
 670 /* suites is a string of colon-separated cipher suite names. */
 671 static int
 672 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 673 {
 674         const char *err;
 675         int rc = gnutls_priority_init( &ctx->prios, suites, &err );
 676         if ( rc )
 677                 ctx->prios = NULL;
 678         return rc;
 679 }
 680
 681 /*
 682  * TLS support for LBER Sockbufs
 683  */
 684
 685 struct tls_data {
 686         tlsg_session            *session;
 687         Sockbuf_IO_Desc         *sbiod;
 688 };
 689
 690 static ssize_t
 691 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 692 {
 693         struct tls_data         *p;
 694
 695         if ( buf == NULL || len <= 0 ) return 0;
 696
 697         p = (struct tls_data *)ptr;
 698
 699         if ( p == NULL || p->sbiod == NULL ) {
 700                 return 0;
 701         }
 702
 703         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 704 }
 705
 706 static ssize_t
 707 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 708 {
 709         struct tls_data         *p;
 710
 711         if ( buf == NULL || len <= 0 ) return 0;
 712
 713         p = (struct tls_data *)ptr;
 714
 715         if ( p == NULL || p->sbiod == NULL ) {
 716                 return 0;
 717         }
 718
 719         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 720 }
 721
 722 static int
 723 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 724 {
 725         struct tls_data         *p;
 726         tlsg_session    *session = arg;
 727
 728         assert( sbiod != NULL );
 729
 730         p = LBER_MALLOC( sizeof( *p ) );
 731         if ( p == NULL ) {
 732                 return -1;
 733         }
 734
 735         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 736         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 737         gnutls_transport_set_push_function( session->session, tlsg_send );
 738         p->session = session;
 739         p->sbiod = sbiod;
 740         sbiod->sbiod_pvt = p;
 741         return 0;
 742 }
 743
 744 static int
 745 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 746 {
 747         struct tls_data         *p;
 748
 749         assert( sbiod != NULL );
 750         assert( sbiod->sbiod_pvt != NULL );
 751
 752         p = (struct tls_data *)sbiod->sbiod_pvt;
 753         gnutls_deinit ( p->session->session );
 754         LBER_FREE( p->session );
 755         LBER_FREE( sbiod->sbiod_pvt );
 756         sbiod->sbiod_pvt = NULL;
 757         return 0;
 758 }
 759
 760 static int
 761 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 762 {
 763         struct tls_data         *p;
 764
 765         assert( sbiod != NULL );
 766         assert( sbiod->sbiod_pvt != NULL );
 767
 768         p = (struct tls_data *)sbiod->sbiod_pvt;
 769         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 770         return 0;
 771 }
 772
 773 static int
 774 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 775 {
 776         struct tls_data         *p;
 777
 778         assert( sbiod != NULL );
 779         assert( sbiod->sbiod_pvt != NULL );
 780
 781         p = (struct tls_data *)sbiod->sbiod_pvt;
 782
 783         if ( opt == LBER_SB_OPT_GET_SSL ) {
 784                 *((tlsg_session **)arg) = p->session;
 785                 return 1;
 786
 787         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 788                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 789                         return 1;
 790                 }
 791         }
 792
 793         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 794 }
 795
 796 static ber_slen_t
 797 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 798 {
 799         struct tls_data         *p;
 800         ber_slen_t              ret;
 801
 802         assert( sbiod != NULL );
 803         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 804
 805         p = (struct tls_data *)sbiod->sbiod_pvt;
 806
 807         ret = gnutls_record_recv ( p->session->session, buf, len );
 808         switch (ret) {
 809         case GNUTLS_E_INTERRUPTED:
 810         case GNUTLS_E_AGAIN:
 811                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 812                 sock_errset(EWOULDBLOCK);
 813                 ret = 0;
 814                 break;
 815         case GNUTLS_E_REHANDSHAKE:
 816                 for ( ret = gnutls_handshake ( p->session->session );
 817                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
 818                       ret = gnutls_handshake ( p->session->session ) );
 819                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 820                 ret = 0;
 821                 break;
 822         default:
 823                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
 824         }
 825         return ret;
 826 }
 827
 828 static ber_slen_t
 829 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 830 {
 831         struct tls_data         *p;
 832         ber_slen_t              ret;
 833
 834         assert( sbiod != NULL );
 835         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 836
 837         p = (struct tls_data *)sbiod->sbiod_pvt;
 838
 839         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
 840
 841         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
 842                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
 843                 sock_errset(EWOULDBLOCK);
 844                 ret = 0;
 845         } else {
 846                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
 847         }
 848         return ret;
 849 }
 850
 851 static Sockbuf_IO tlsg_sbio =
 852 {
 853         tlsg_sb_setup,          /* sbi_setup */
 854         tlsg_sb_remove,         /* sbi_remove */
 855         tlsg_sb_ctrl,           /* sbi_ctrl */
 856         tlsg_sb_read,           /* sbi_read */
 857         tlsg_sb_write,          /* sbi_write */
 858         tlsg_sb_close           /* sbi_close */
 859 };
 860
 861 /* Certs are not automatically varified during the handshake */
 862 static int
 863 tlsg_cert_verify( tlsg_session *ssl )
 864 {
 865         unsigned int status = 0;
 866         int err;
 867         time_t now = time(0);
 868         time_t peertime;
 869
 870         err = gnutls_certificate_verify_peers2( ssl->session, &status );
 871         if ( err < 0 ) {
 872                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
 873                         err,0,0 );
 874                 return -1;
 875         }
 876         if ( status ) {
 877                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
 878                         status, 0,0 );
 879                 return -1;
 880         }
 881         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
 882         if ( peertime == (time_t) -1 ) {
 883                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
 884                         0, 0, 0 );
 885                 return -1;
 886         }
 887         if ( peertime < now ) {
 888                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
 889                         0, 0, 0 );
 890                 return -1;
 891         }
 892         peertime = gnutls_certificate_activation_time_peers( ssl->session );
 893         if ( peertime == (time_t) -1 ) {
 894                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
 895                         0, 0, 0 );
 896                 return -1;
 897         }
 898         if ( peertime > now ) {
 899                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
 900                         0, 0, 0 );
 901                 return -1;
 902         }
 903         return 0;
 904 }
 905
 906 tls_impl ldap_int_tls_impl = {
 907         "GnuTLS",
 908
 909         tlsg_init,
 910         tlsg_destroy,
 911
 912         tlsg_ctx_new,
 913         tlsg_ctx_ref,
 914         tlsg_ctx_free,
 915         tlsg_ctx_init,
 916
 917         tlsg_session_new,
 918         tlsg_session_connect,
 919         tlsg_session_accept,
 920         tlsg_session_upflags,
 921         tlsg_session_errmsg,
 922         tlsg_session_my_dn,
 923         tlsg_session_peer_dn,
 924         tlsg_session_chkhost,
 925         tlsg_session_strength,
 926
 927         &tlsg_sbio,
 928
 929 #ifdef LDAP_R_COMPILE
 930         tlsg_thr_init,
 931 #else
 932         NULL,
 933 #endif
 934
 935         0
 936 };
 937
 938 #endif /* HAVE_GNUTLS */