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 2008-2014 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 #define DH_BITS (1024)
  48
  49 typedef struct tlsg_ctx {
  50         struct ldapoptions *lo;
  51         gnutls_certificate_credentials_t cred;
  52         gnutls_dh_params_t dh_params;
  53         unsigned long verify_depth;
  54         int refcount;
  55         gnutls_priority_t prios;
  56 #ifdef LDAP_R_COMPILE
  57         ldap_pvt_thread_mutex_t ref_mutex;
  58 #endif
  59 } tlsg_ctx;
  60
  61 typedef struct tlsg_session {
  62         gnutls_session_t session;
  63         tlsg_ctx *ctx;
  64         struct berval peer_der_dn;
  65 } tlsg_session;
  66
  67 static int tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites );
  68 static int tlsg_cert_verify( tlsg_session *s );
  69
  70 #ifdef LDAP_R_COMPILE
  71
  72 static int
  73 tlsg_mutex_init( void **priv )
  74 {
  75         int err = 0;
  76         ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t ));
  77
  78         if ( !lock )
  79                 err = ENOMEM;
  80         if ( !err ) {
  81                 err = ldap_pvt_thread_mutex_init( lock );
  82                 if ( err )
  83                         LDAP_FREE( lock );
  84                 else
  85                         *priv = lock;
  86         }
  87         return err;
  88 }
  89
  90 static int
  91 tlsg_mutex_destroy( void **lock )
  92 {
  93         int err = ldap_pvt_thread_mutex_destroy( *lock );
  94         LDAP_FREE( *lock );
  95         return err;
  96 }
  97
  98 static int
  99 tlsg_mutex_lock( void **lock )
 100 {
 101         return ldap_pvt_thread_mutex_lock( *lock );
 102 }
 103
 104 static int
 105 tlsg_mutex_unlock( void **lock )
 106 {
 107         return ldap_pvt_thread_mutex_unlock( *lock );
 108 }
 109
 110 static void
 111 tlsg_thr_init( void )
 112 {
 113         gnutls_global_set_mutex (tlsg_mutex_init,
 114                 tlsg_mutex_destroy,
 115                 tlsg_mutex_lock,
 116                 tlsg_mutex_unlock);
 117 }
 118 #endif /* LDAP_R_COMPILE */
 119
 120 /*
 121  * Initialize TLS subsystem. Should be called only once.
 122  */
 123 static int
 124 tlsg_init( void )
 125 {
 126         gnutls_global_init();
 127         return 0;
 128 }
 129
 130 /*
 131  * Tear down the TLS subsystem. Should only be called once.
 132  */
 133 static void
 134 tlsg_destroy( void )
 135 {
 136         gnutls_global_deinit();
 137 }
 138
 139 static tls_ctx *
 140 tlsg_ctx_new ( struct ldapoptions *lo )
 141 {
 142         tlsg_ctx *ctx;
 143
 144         ctx = ber_memcalloc ( 1, sizeof (*ctx) );
 145         if ( ctx ) {
 146                 ctx->lo = lo;
 147                 if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
 148                         ber_memfree( ctx );
 149                         return NULL;
 150                 }
 151                 ctx->refcount = 1;
 152                 gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
 153 #ifdef LDAP_R_COMPILE
 154                 ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
 155 #endif
 156         }
 157         return (tls_ctx *)ctx;
 158 }
 159
 160 static void
 161 tlsg_ctx_ref( tls_ctx *ctx )
 162 {
 163         tlsg_ctx *c = (tlsg_ctx *)ctx;
 164         LDAP_MUTEX_LOCK( &c->ref_mutex );
 165         c->refcount++;
 166         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 167 }
 168
 169 static void
 170 tlsg_ctx_free ( tls_ctx *ctx )
 171 {
 172         tlsg_ctx *c = (tlsg_ctx *)ctx;
 173         int refcount;
 174
 175         if ( !c ) return;
 176
 177         LDAP_MUTEX_LOCK( &c->ref_mutex );
 178         refcount = --c->refcount;
 179         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 180         if ( refcount )
 181                 return;
 182         gnutls_priority_deinit( c->prios );
 183         gnutls_certificate_free_credentials( c->cred );
 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_dhfile ) {
 295                 Debug( LDAP_DEBUG_ANY,
 296                        "TLS: warning: ignoring dhfile\n",
 297                        NULL, NULL, NULL );
 298         }
 299
 300         if ( lo->ldo_tls_crlfile ) {
 301                 rc = gnutls_certificate_set_x509_crl_file(
 302                         ctx->cred,
 303                         lt->lt_crlfile,
 304                         GNUTLS_X509_FMT_PEM );
 305                 if ( rc < 0 ) return -1;
 306                 rc = 0;
 307         }
 308
 309         /* FIXME: ITS#5992 - this should go be configurable,
 310          * and V1 CA certs should be phased out ASAP.
 311          */
 312         gnutls_certificate_set_verify_flags( ctx->cred,
 313                 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
 314
 315         if ( is_server ) {
 316                 gnutls_dh_params_init(&ctx->dh_params);
 317                 gnutls_dh_params_generate2(ctx->dh_params, DH_BITS);
 318         }
 319         return 0;
 320 }
 321
 322 static tls_session *
 323 tlsg_session_new ( tls_ctx * ctx, int is_server )
 324 {
 325         tlsg_ctx *c = (tlsg_ctx *)ctx;
 326         tlsg_session *session;
 327
 328         session = ber_memcalloc ( 1, sizeof (*session) );
 329         if ( !session )
 330                 return NULL;
 331
 332         session->ctx = c;
 333         gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
 334         gnutls_priority_set( session->session, c->prios );
 335         if ( c->cred )
 336                 gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
 337
 338         if ( is_server ) {
 339                 int flag = 0;
 340                 if ( c->lo->ldo_tls_require_cert ) {
 341                         flag = GNUTLS_CERT_REQUEST;
 342                         if ( c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
 343                                 c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD )
 344                                 flag = GNUTLS_CERT_REQUIRE;
 345                         gnutls_certificate_server_set_request( session->session, flag );
 346                 }
 347         }
 348         return (tls_session *)session;
 349 }
 350
 351 static int
 352 tlsg_session_accept( tls_session *session )
 353 {
 354         tlsg_session *s = (tlsg_session *)session;
 355         int rc;
 356
 357         rc = gnutls_handshake( s->session );
 358         if ( rc == 0 && s->ctx->lo->ldo_tls_require_cert != LDAP_OPT_X_TLS_NEVER ) {
 359                 const gnutls_datum_t *peer_cert_list;
 360                 unsigned int list_size;
 361
 362                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 363                                                 &list_size );
 364                 if ( !peer_cert_list && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_TRY )
 365                         rc = 0;
 366                 else {
 367                         rc = tlsg_cert_verify( s );
 368                         if ( rc && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW )
 369                                 rc = 0;
 370                 }
 371         }
 372         return rc;
 373 }
 374
 375 static int
 376 tlsg_session_connect( LDAP *ld, tls_session *session )
 377 {
 378         return tlsg_session_accept( session);
 379 }
 380
 381 static int
 382 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 383 {
 384         tlsg_session *s = (tlsg_session *)session;
 385
 386         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 387                 return 0;
 388
 389         switch (gnutls_record_get_direction (s->session)) {
 390         case 0:
 391                 sb->sb_trans_needs_read = 1;
 392                 return 1;
 393         case 1:
 394                 sb->sb_trans_needs_write = 1;
 395                 return 1;
 396         }
 397         return 0;
 398 }
 399
 400 static char *
 401 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 402 {
 403         return (char *)gnutls_strerror( rc );
 404 }
 405
 406 static void
 407 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 408 {
 409         BerElementBuffer berbuf;
 410         BerElement *ber = (BerElement *)&berbuf;
 411         ber_tag_t tag;
 412         ber_len_t len;
 413         ber_int_t i;
 414
 415         ber_init2( ber, cert, LBER_USE_DER );
 416         tag = ber_skip_tag( ber, &len );        /* Sequence */
 417         tag = ber_skip_tag( ber, &len );        /* Sequence */
 418         tag = ber_peek_tag( ber, &len );        /* Context + Constructed (version) */
 419         if ( tag == 0xa0 ) {    /* Version is optional */
 420                 tag = ber_skip_tag( ber, &len );
 421                 tag = ber_get_int( ber, &i );   /* Int: Version */
 422         }
 423         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 424         ber_skip_data( ber, len );
 425         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 426         ber_skip_data( ber, len );
 427         if ( !get_subject ) {
 428                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 429         } else {
 430                 tag = ber_skip_tag( ber, &len );
 431                 ber_skip_data( ber, len );
 432                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 433                 ber_skip_data( ber, len );
 434                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 435         }
 436         len = ber_ptrlen( ber );
 437         dn->bv_val = cert->bv_val + len;
 438         dn->bv_len = cert->bv_len - len;
 439 }
 440
 441 static int
 442 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 443 {
 444         tlsg_session *s = (tlsg_session *)session;
 445         const gnutls_datum_t *x;
 446         struct berval bv;
 447
 448         x = gnutls_certificate_get_ours( s->session );
 449
 450         if (!x) return LDAP_INVALID_CREDENTIALS;
 451
 452         bv.bv_val = (char *) x->data;
 453         bv.bv_len = x->size;
 454
 455         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 456         return 0;
 457 }
 458
 459 static int
 460 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 461 {
 462         tlsg_session *s = (tlsg_session *)session;
 463         if ( !s->peer_der_dn.bv_val ) {
 464                 const gnutls_datum_t *peer_cert_list;
 465                 unsigned int list_size;
 466                 struct berval bv;
 467
 468                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 469                                                         &list_size );
 470                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 471
 472                 bv.bv_len = peer_cert_list->size;
 473                 bv.bv_val = (char *) peer_cert_list->data;
 474
 475                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 476         }
 477         *der_dn = s->peer_der_dn;
 478         return 0;
 479 }
 480
 481 /* what kind of hostname were we given? */
 482 #define IS_DNS  0
 483 #define IS_IP4  1
 484 #define IS_IP6  2
 485
 486 #define CN_OID  "2.5.4.3"
 487
 488 static int
 489 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 490 {
 491         tlsg_session *s = (tlsg_session *)session;
 492         int i, ret;
 493         const gnutls_datum_t *peer_cert_list;
 494         unsigned int list_size;
 495         char altname[NI_MAXHOST];
 496         size_t altnamesize;
 497
 498         gnutls_x509_crt_t cert;
 499         const char *name;
 500         char *ptr;
 501         char *domain = NULL;
 502 #ifdef LDAP_PF_INET6
 503         struct in6_addr addr;
 504 #else
 505         struct in_addr addr;
 506 #endif
 507         int len1 = 0, len2 = 0;
 508         int ntype = IS_DNS;
 509
 510         if( ldap_int_hostname &&
 511                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 512         {
 513                 name = ldap_int_hostname;
 514         } else {
 515                 name = name_in;
 516         }
 517
 518         peer_cert_list = gnutls_certificate_get_peers( s->session,
 519                                                 &list_size );
 520         if ( !peer_cert_list ) {
 521                 Debug( LDAP_DEBUG_ANY,
 522                         "TLS: unable to get peer certificate.\n",
 523                         0, 0, 0 );
 524                 /* If this was a fatal condition, things would have
 525                  * aborted long before now.
 526                  */
 527                 return LDAP_SUCCESS;
 528         }
 529         ret = gnutls_x509_crt_init( &cert );
 530         if ( ret < 0 )
 531                 return LDAP_LOCAL_ERROR;
 532         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 533         if ( ret ) {
 534                 gnutls_x509_crt_deinit( cert );
 535                 return LDAP_LOCAL_ERROR;
 536         }
 537
 538 #ifdef LDAP_PF_INET6
 539         if (inet_pton(AF_INET6, name, &addr)) {
 540                 ntype = IS_IP6;
 541         } else
 542 #endif
 543         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 544                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 545         }
 546
 547         if (ntype == IS_DNS) {
 548                 len1 = strlen(name);
 549                 domain = strchr(name, '.');
 550                 if (domain) {
 551                         len2 = len1 - (domain-name);
 552                 }
 553         }
 554
 555         for ( i=0, ret=0; ret >= 0; i++ ) {
 556                 altnamesize = sizeof(altname);
 557                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 558                         altname, &altnamesize, NULL );
 559                 if ( ret < 0 ) break;
 560
 561                 /* ignore empty */
 562                 if ( altnamesize == 0 ) continue;
 563
 564                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 565                         if (ntype != IS_DNS) continue;
 566
 567                         /* Is this an exact match? */
 568                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 569                                 break;
 570                         }
 571
 572                         /* Is this a wildcard match? */
 573                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 574                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 575                         {
 576                                 break;
 577                         }
 578                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 579                         if (ntype == IS_DNS) continue;
 580
 581 #ifdef LDAP_PF_INET6
 582                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 583                                 continue;
 584                         } else
 585 #endif
 586                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 587                                 continue;
 588                         }
 589                         if (!memcmp(altname, &addr, altnamesize)) {
 590                                 break;
 591                         }
 592                 }
 593         }
 594         if ( ret >= 0 ) {
 595                 ret = LDAP_SUCCESS;
 596         } else {
 597                 /* find the last CN */
 598                 i=0;
 599                 do {
 600                         altnamesize = 0;
 601                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 602                                 i, 1, altname, &altnamesize );
 603                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 604                                 i++;
 605                         else
 606                                 break;
 607                 } while ( 1 );
 608
 609                 if ( i ) {
 610                         altnamesize = sizeof(altname);
 611                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 612                                 i-1, 0, altname, &altnamesize );
 613                 }
 614
 615                 if ( ret < 0 ) {
 616                         Debug( LDAP_DEBUG_ANY,
 617                                 "TLS: unable to get common name from peer certificate.\n",
 618                                 0, 0, 0 );
 619                         ret = LDAP_CONNECT_ERROR;
 620                         if ( ld->ld_error ) {
 621                                 LDAP_FREE( ld->ld_error );
 622                         }
 623                         ld->ld_error = LDAP_STRDUP(
 624                                 _("TLS: unable to get CN from peer certificate"));
 625
 626                 } else {
 627                         ret = LDAP_LOCAL_ERROR;
 628                         if ( !len1 ) len1 = strlen( name );
 629                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 630                                 ret = LDAP_SUCCESS;
 631
 632                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 633                                         /* Is this a wildcard match? */
 634                                 if( domain &&
 635                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 636                                         ret = LDAP_SUCCESS;
 637                                 }
 638                         }
 639                 }
 640
 641                 if( ret == LDAP_LOCAL_ERROR ) {
 642                         altname[altnamesize] = '\0';
 643                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 644                                 "common name in certificate (%s).\n",
 645                                 name, altname, 0 );
 646                         ret = LDAP_CONNECT_ERROR;
 647                         if ( ld->ld_error ) {
 648                                 LDAP_FREE( ld->ld_error );
 649                         }
 650                         ld->ld_error = LDAP_STRDUP(
 651                                 _("TLS: hostname does not match CN in peer certificate"));
 652                 }
 653         }
 654         gnutls_x509_crt_deinit( cert );
 655         return ret;
 656 }
 657
 658 static int
 659 tlsg_session_strength( tls_session *session )
 660 {
 661         tlsg_session *s = (tlsg_session *)session;
 662         gnutls_cipher_algorithm_t c;
 663
 664         c = gnutls_cipher_get( s->session );
 665         return gnutls_cipher_get_key_size( c ) * 8;
 666 }
 667
 668 /* suites is a string of colon-separated cipher suite names. */
 669 static int
 670 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 671 {
 672         const char *err;
 673         int rc = gnutls_priority_init( &ctx->prios, suites, &err );
 674         if ( rc )
 675                 ctx->prios = NULL;
 676         return rc;
 677 }
 678
 679 /*
 680  * TLS support for LBER Sockbufs
 681  */
 682
 683 struct tls_data {
 684         tlsg_session            *session;
 685         Sockbuf_IO_Desc         *sbiod;
 686 };
 687
 688 static ssize_t
 689 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 690 {
 691         struct tls_data         *p;
 692
 693         if ( buf == NULL || len <= 0 ) return 0;
 694
 695         p = (struct tls_data *)ptr;
 696
 697         if ( p == NULL || p->sbiod == NULL ) {
 698                 return 0;
 699         }
 700
 701         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 702 }
 703
 704 static ssize_t
 705 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 706 {
 707         struct tls_data         *p;
 708
 709         if ( buf == NULL || len <= 0 ) return 0;
 710
 711         p = (struct tls_data *)ptr;
 712
 713         if ( p == NULL || p->sbiod == NULL ) {
 714                 return 0;
 715         }
 716
 717         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 718 }
 719
 720 static int
 721 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 722 {
 723         struct tls_data         *p;
 724         tlsg_session    *session = arg;
 725
 726         assert( sbiod != NULL );
 727
 728         p = LBER_MALLOC( sizeof( *p ) );
 729         if ( p == NULL ) {
 730                 return -1;
 731         }
 732
 733         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 734         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 735         gnutls_transport_set_push_function( session->session, tlsg_send );
 736         p->session = session;
 737         p->sbiod = sbiod;
 738         sbiod->sbiod_pvt = p;
 739         return 0;
 740 }
 741
 742 static int
 743 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 744 {
 745         struct tls_data         *p;
 746
 747         assert( sbiod != NULL );
 748         assert( sbiod->sbiod_pvt != NULL );
 749
 750         p = (struct tls_data *)sbiod->sbiod_pvt;
 751         gnutls_deinit ( p->session->session );
 752         LBER_FREE( p->session );
 753         LBER_FREE( sbiod->sbiod_pvt );
 754         sbiod->sbiod_pvt = NULL;
 755         return 0;
 756 }
 757
 758 static int
 759 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 760 {
 761         struct tls_data         *p;
 762
 763         assert( sbiod != NULL );
 764         assert( sbiod->sbiod_pvt != NULL );
 765
 766         p = (struct tls_data *)sbiod->sbiod_pvt;
 767         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 768         return 0;
 769 }
 770
 771 static int
 772 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 773 {
 774         struct tls_data         *p;
 775
 776         assert( sbiod != NULL );
 777         assert( sbiod->sbiod_pvt != NULL );
 778
 779         p = (struct tls_data *)sbiod->sbiod_pvt;
 780
 781         if ( opt == LBER_SB_OPT_GET_SSL ) {
 782                 *((tlsg_session **)arg) = p->session;
 783                 return 1;
 784
 785         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 786                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 787                         return 1;
 788                 }
 789         }
 790
 791         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 792 }
 793
 794 static ber_slen_t
 795 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 796 {
 797         struct tls_data         *p;
 798         ber_slen_t              ret;
 799
 800         assert( sbiod != NULL );
 801         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 802
 803         p = (struct tls_data *)sbiod->sbiod_pvt;
 804
 805         ret = gnutls_record_recv ( p->session->session, buf, len );
 806         switch (ret) {
 807         case GNUTLS_E_INTERRUPTED:
 808         case GNUTLS_E_AGAIN:
 809                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 810                 sock_errset(EWOULDBLOCK);
 811                 ret = 0;
 812                 break;
 813         case GNUTLS_E_REHANDSHAKE:
 814                 for ( ret = gnutls_handshake ( p->session->session );
 815                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
 816                       ret = gnutls_handshake ( p->session->session ) );
 817                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
 818                 ret = 0;
 819                 break;
 820         default:
 821                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
 822         }
 823         return ret;
 824 }
 825
 826 static ber_slen_t
 827 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 828 {
 829         struct tls_data         *p;
 830         ber_slen_t              ret;
 831
 832         assert( sbiod != NULL );
 833         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
 834
 835         p = (struct tls_data *)sbiod->sbiod_pvt;
 836
 837         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
 838
 839         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
 840                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
 841                 sock_errset(EWOULDBLOCK);
 842                 ret = 0;
 843         } else {
 844                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
 845         }
 846         return ret;
 847 }
 848
 849 static Sockbuf_IO tlsg_sbio =
 850 {
 851         tlsg_sb_setup,          /* sbi_setup */
 852         tlsg_sb_remove,         /* sbi_remove */
 853         tlsg_sb_ctrl,           /* sbi_ctrl */
 854         tlsg_sb_read,           /* sbi_read */
 855         tlsg_sb_write,          /* sbi_write */
 856         tlsg_sb_close           /* sbi_close */
 857 };
 858
 859 /* Certs are not automatically varified during the handshake */
 860 static int
 861 tlsg_cert_verify( tlsg_session *ssl )
 862 {
 863         unsigned int status = 0;
 864         int err;
 865         time_t now = time(0);
 866         time_t peertime;
 867
 868         err = gnutls_certificate_verify_peers2( ssl->session, &status );
 869         if ( err < 0 ) {
 870                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
 871                         err,0,0 );
 872                 return -1;
 873         }
 874         if ( status ) {
 875                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
 876                         status, 0,0 );
 877                 return -1;
 878         }
 879         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
 880         if ( peertime == (time_t) -1 ) {
 881                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
 882                         0, 0, 0 );
 883                 return -1;
 884         }
 885         if ( peertime < now ) {
 886                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
 887                         0, 0, 0 );
 888                 return -1;
 889         }
 890         peertime = gnutls_certificate_activation_time_peers( ssl->session );
 891         if ( peertime == (time_t) -1 ) {
 892                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
 893                         0, 0, 0 );
 894                 return -1;
 895         }
 896         if ( peertime > now ) {
 897                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
 898                         0, 0, 0 );
 899                 return -1;
 900         }
 901         return 0;
 902 }
 903
 904 tls_impl ldap_int_tls_impl = {
 905         "GnuTLS",
 906
 907         tlsg_init,
 908         tlsg_destroy,
 909
 910         tlsg_ctx_new,
 911         tlsg_ctx_ref,
 912         tlsg_ctx_free,
 913         tlsg_ctx_init,
 914
 915         tlsg_session_new,
 916         tlsg_session_connect,
 917         tlsg_session_accept,
 918         tlsg_session_upflags,
 919         tlsg_session_errmsg,
 920         tlsg_session_my_dn,
 921         tlsg_session_peer_dn,
 922         tlsg_session_chkhost,
 923         tlsg_session_strength,
 924
 925         &tlsg_sbio,
 926
 927 #ifdef LDAP_R_COMPILE
 928         tlsg_thr_init,
 929 #else
 930         NULL,
 931 #endif
 932
 933         0
 934 };
 935
 936 #endif /* HAVE_GNUTLS */