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 2008-2013 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 #include <gcrypt.h>
  47
  48 #if LIBGNUTLS_VERSION_NUMBER >= 0x020200
  49 #define HAVE_CIPHERSUITES       1
  50 /* This is a kludge. gcrypt 1.4.x has support. Recent GnuTLS requires gcrypt 1.4.x
  51  * but that dependency isn't reflected in their configure script, resulting in
  52  * build errors on older gcrypt. So, if they have a working build environment,
  53  * assume gcrypt is new enough.
  54  */
  55 #define HAVE_GCRYPT_RAND        1
  56 #else
  57 #undef HAVE_CIPHERSUITES
  58 #undef HAVE_GCRYPT_RAND
  59 #endif
  60
  61 #ifndef HAVE_CIPHERSUITES
  62 /* Versions prior to 2.2.0 didn't handle cipher suites, so we had to
  63  * kludge them ourselves.
  64  */
  65 typedef struct tls_cipher_suite {
  66         const char *name;
  67         gnutls_kx_algorithm_t kx;
  68         gnutls_cipher_algorithm_t cipher;
  69         gnutls_mac_algorithm_t mac;
  70         gnutls_protocol_t version;
  71 } tls_cipher_suite;
  72 #endif
  73
  74 typedef struct tlsg_ctx {
  75         struct ldapoptions *lo;
  76         gnutls_certificate_credentials_t cred;
  77         gnutls_dh_params_t dh_params;
  78         unsigned long verify_depth;
  79         int refcount;
  80 #ifdef HAVE_CIPHERSUITES
  81         gnutls_priority_t prios;
  82 #else
  83         int *kx_list;
  84         int *cipher_list;
  85         int *mac_list;
  86 #endif
  87 #ifdef LDAP_R_COMPILE
  88         ldap_pvt_thread_mutex_t ref_mutex;
  89 #endif
  90 } tlsg_ctx;
  91
  92 typedef struct tlsg_session {
  93         gnutls_session_t session;
  94         tlsg_ctx *ctx;
  95         struct berval peer_der_dn;
  96 } tlsg_session;
  97
  98 #ifndef HAVE_CIPHERSUITES
  99 static tls_cipher_suite *tlsg_ciphers;
 100 static int tlsg_n_ciphers;
 101 #endif
 102
 103 static int tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites );
 104 static int tlsg_cert_verify( tlsg_session *s );
 105
 106 #ifdef LDAP_R_COMPILE
 107
 108 static int
 109 tlsg_mutex_init( void **priv )
 110 {
 111         int err = 0;
 112         ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t ));
 113
 114         if ( !lock )
 115                 err = ENOMEM;
 116         if ( !err ) {
 117                 err = ldap_pvt_thread_mutex_init( lock );
 118                 if ( err )
 119                         LDAP_FREE( lock );
 120                 else
 121                         *priv = lock;
 122         }
 123         return err;
 124 }
 125
 126 static int
 127 tlsg_mutex_destroy( void **lock )
 128 {
 129         int err = ldap_pvt_thread_mutex_destroy( *lock );
 130         LDAP_FREE( *lock );
 131         return err;
 132 }
 133
 134 static int
 135 tlsg_mutex_lock( void **lock )
 136 {
 137         return ldap_pvt_thread_mutex_lock( *lock );
 138 }
 139
 140 static int
 141 tlsg_mutex_unlock( void **lock )
 142 {
 143         return ldap_pvt_thread_mutex_unlock( *lock );
 144 }
 145
 146 static struct gcry_thread_cbs tlsg_thread_cbs = {
 147         GCRY_THREAD_OPTION_USER,
 148         NULL,
 149         tlsg_mutex_init,
 150         tlsg_mutex_destroy,
 151         tlsg_mutex_lock,
 152         tlsg_mutex_unlock,
 153         NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
 154 };
 155
 156 static void
 157 tlsg_thr_init( void )
 158 {
 159         gcry_control (GCRYCTL_SET_THREAD_CBS, &tlsg_thread_cbs);
 160 }
 161 #endif /* LDAP_R_COMPILE */
 162
 163 /*
 164  * Initialize TLS subsystem. Should be called only once.
 165  */
 166 static int
 167 tlsg_init( void )
 168 {
 169 #ifdef HAVE_GCRYPT_RAND
 170         struct ldapoptions *lo = LDAP_INT_GLOBAL_OPT();
 171         if ( lo->ldo_tls_randfile &&
 172                 gcry_control( GCRYCTL_SET_RNDEGD_SOCKET, lo->ldo_tls_randfile )) {
 173                 Debug( LDAP_DEBUG_ANY,
 174                 "TLS: gcry_control GCRYCTL_SET_RNDEGD_SOCKET failed\n",
 175                 0, 0, 0);
 176                 return -1;
 177         }
 178 #endif
 179
 180         gnutls_global_init();
 181
 182 #ifndef HAVE_CIPHERSUITES
 183         /* GNUtls cipher suite handling: The library ought to parse suite
 184          * names for us, but it doesn't. It will return a list of suite names
 185          * that it supports, so we can do parsing ourselves. It ought to tell
 186          * us how long the list is, but it doesn't do that either, so we just
 187          * have to count it manually...
 188          */
 189         {
 190                 int i = 0;
 191                 tls_cipher_suite *ptr, tmp;
 192                 char cs_id[2];
 193
 194                 while ( gnutls_cipher_suite_info( i, cs_id, &tmp.kx, &tmp.cipher,
 195                         &tmp.mac, &tmp.version ))
 196                         i++;
 197                 tlsg_n_ciphers = i;
 198
 199                 /* Store a copy */
 200                 tlsg_ciphers = LDAP_MALLOC(tlsg_n_ciphers * sizeof(tls_cipher_suite));
 201                 if ( !tlsg_ciphers )
 202                         return -1;
 203                 for ( i=0; i<tlsg_n_ciphers; i++ ) {
 204                         tlsg_ciphers[i].name = gnutls_cipher_suite_info( i, cs_id,
 205                                 &tlsg_ciphers[i].kx, &tlsg_ciphers[i].cipher, &tlsg_ciphers[i].mac,
 206                                 &tlsg_ciphers[i].version );
 207                 }
 208         }
 209 #endif
 210         return 0;
 211 }
 212
 213 /*
 214  * Tear down the TLS subsystem. Should only be called once.
 215  */
 216 static void
 217 tlsg_destroy( void )
 218 {
 219 #ifndef HAVE_CIPHERSUITES
 220         LDAP_FREE( tlsg_ciphers );
 221         tlsg_ciphers = NULL;
 222         tlsg_n_ciphers = 0;
 223 #endif
 224         gnutls_global_deinit();
 225 }
 226
 227 static tls_ctx *
 228 tlsg_ctx_new ( struct ldapoptions *lo )
 229 {
 230         tlsg_ctx *ctx;
 231
 232         ctx = ber_memcalloc ( 1, sizeof (*ctx) );
 233         if ( ctx ) {
 234                 ctx->lo = lo;
 235                 if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
 236                         ber_memfree( ctx );
 237                         return NULL;
 238                 }
 239                 ctx->refcount = 1;
 240 #ifdef HAVE_CIPHERSUITES
 241                 gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
 242 #endif
 243 #ifdef LDAP_R_COMPILE
 244                 ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
 245 #endif
 246         }
 247         return (tls_ctx *)ctx;
 248 }
 249
 250 static void
 251 tlsg_ctx_ref( tls_ctx *ctx )
 252 {
 253         tlsg_ctx *c = (tlsg_ctx *)ctx;
 254         LDAP_MUTEX_LOCK( &c->ref_mutex );
 255         c->refcount++;
 256         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 257 }
 258
 259 static void
 260 tlsg_ctx_free ( tls_ctx *ctx )
 261 {
 262         tlsg_ctx *c = (tlsg_ctx *)ctx;
 263         int refcount;
 264
 265         if ( !c ) return;
 266
 267         LDAP_MUTEX_LOCK( &c->ref_mutex );
 268         refcount = --c->refcount;
 269         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 270         if ( refcount )
 271                 return;
 272 #ifdef HAVE_CIPHERSUITES
 273         gnutls_priority_deinit( c->prios );
 274 #else
 275         LDAP_FREE( c->kx_list );
 276 #endif
 277         gnutls_certificate_free_credentials( c->cred );
 278         if ( c->dh_params )
 279                 gnutls_dh_params_deinit( c->dh_params );
 280         ber_memfree ( c );
 281 }
 282
 283 static int
 284 tlsg_getfile( const char *path, gnutls_datum_t *buf )
 285 {
 286         int rc = -1, fd;
 287         struct stat st;
 288
 289         fd = open( path, O_RDONLY );
 290         if ( fd >= 0 && fstat( fd, &st ) == 0 ) {
 291                 buf->size = st.st_size;
 292                 buf->data = LDAP_MALLOC( st.st_size + 1 );
 293                 if ( buf->data ) {
 294                         rc = read( fd, buf->data, st.st_size );
 295                         close( fd );
 296                         if ( rc < st.st_size )
 297                                 rc = -1;
 298                         else
 299                                 rc = 0;
 300                 }
 301         }
 302         return rc;
 303 }
 304
 305 /* This is the GnuTLS default */
 306 #define VERIFY_DEPTH    6
 307
 308 /*
 309  * initialize a new TLS context
 310  */
 311 static int
 312 tlsg_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
 313 {
 314         tlsg_ctx *ctx = lo->ldo_tls_ctx;
 315         int rc;
 316
 317         if ( lo->ldo_tls_ciphersuite &&
 318                 tlsg_parse_ciphers( ctx, lt->lt_ciphersuite )) {
 319                 Debug( LDAP_DEBUG_ANY,
 320                            "TLS: could not set cipher list %s.\n",
 321                            lo->ldo_tls_ciphersuite, 0, 0 );
 322                 return -1;
 323         }
 324
 325         if (lo->ldo_tls_cacertdir != NULL) {
 326                 Debug( LDAP_DEBUG_ANY,
 327                        "TLS: warning: cacertdir not implemented for gnutls\n",
 328                        NULL, NULL, NULL );
 329         }
 330
 331         if (lo->ldo_tls_cacertfile != NULL) {
 332                 rc = gnutls_certificate_set_x509_trust_file(
 333                         ctx->cred,
 334                         lt->lt_cacertfile,
 335                         GNUTLS_X509_FMT_PEM );
 336                 if ( rc < 0 ) return -1;
 337         }
 338
 339         if ( lo->ldo_tls_certfile && lo->ldo_tls_keyfile ) {
 340                 gnutls_x509_privkey_t key;
 341                 gnutls_datum_t buf;
 342                 gnutls_x509_crt_t certs[VERIFY_DEPTH];
 343                 unsigned int max = VERIFY_DEPTH;
 344
 345                 rc = gnutls_x509_privkey_init( &key );
 346                 if ( rc ) return -1;
 347
 348                 /* OpenSSL builds the cert chain for us, but GnuTLS
 349                  * expects it to be present in the certfile. If it's
 350                  * not, we have to build it ourselves. So we have to
 351                  * do some special checks here...
 352                  */
 353                 rc = tlsg_getfile( lt->lt_keyfile, &buf );
 354                 if ( rc ) return -1;
 355                 rc = gnutls_x509_privkey_import( key, &buf,
 356                         GNUTLS_X509_FMT_PEM );
 357                 LDAP_FREE( buf.data );
 358                 if ( rc < 0 ) return rc;
 359
 360                 rc = tlsg_getfile( lt->lt_certfile, &buf );
 361                 if ( rc ) return -1;
 362                 rc = gnutls_x509_crt_list_import( certs, &max, &buf,
 363                         GNUTLS_X509_FMT_PEM, 0 );
 364                 LDAP_FREE( buf.data );
 365                 if ( rc < 0 ) return rc;
 366
 367                 /* If there's only one cert and it's not self-signed,
 368                  * then we have to build the cert chain.
 369                  */
 370                 if ( max == 1 && !gnutls_x509_crt_check_issuer( certs[0], certs[0] )) {
 371                         gnutls_x509_crt_t *cas;
 372                         unsigned int i, j, ncas;
 373
 374                         gnutls_certificate_get_x509_cas( ctx->cred, &cas, &ncas );
 375                         for ( i = 1; i<VERIFY_DEPTH; i++ ) {
 376                                 for ( j = 0; j<ncas; j++ ) {
 377                                         if ( gnutls_x509_crt_check_issuer( certs[i-1], cas[j] )) {
 378                                                 certs[i] = cas[j];
 379                                                 max++;
 380                                                 /* If this CA is self-signed, we're done */
 381                                                 if ( gnutls_x509_crt_check_issuer( cas[j], cas[j] ))
 382                                                         j = ncas;
 383                                                 break;
 384                                         }
 385                                 }
 386                                 /* only continue if we found a CA and it was not self-signed */
 387                                 if ( j == ncas )
 388                                         break;
 389                         }
 390                 }
 391                 rc = gnutls_certificate_set_x509_key( ctx->cred, certs, max, key );
 392                 if ( rc ) return -1;
 393         } else if ( lo->ldo_tls_certfile || lo->ldo_tls_keyfile ) {
 394                 Debug( LDAP_DEBUG_ANY,
 395                        "TLS: only one of certfile and keyfile specified\n",
 396                        NULL, NULL, NULL );
 397                 return -1;
 398         }
 399
 400         if ( lo->ldo_tls_crlfile ) {
 401                 rc = gnutls_certificate_set_x509_crl_file(
 402                         ctx->cred,
 403                         lt->lt_crlfile,
 404                         GNUTLS_X509_FMT_PEM );
 405                 if ( rc < 0 ) return -1;
 406                 rc = 0;
 407         }
 408
 409         /* FIXME: ITS#5992 - this should go be configurable,
 410          * and V1 CA certs should be phased out ASAP.
 411          */
 412         gnutls_certificate_set_verify_flags( ctx->cred,
 413                 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
 414
 415         if ( is_server && lo->ldo_tls_dhfile ) {
 416                 gnutls_datum_t buf;
 417                 rc = tlsg_getfile( lo->ldo_tls_dhfile, &buf );
 418                 if ( rc ) return -1;
 419                 rc = gnutls_dh_params_init(&ctx->dh_params);
 420                 if ( rc ) {
 421                         LDAP_FREE( buf.data );
 422                         return -1;
 423                 }
 424                 rc = gnutls_dh_params_import_pkcs3( ctx->dh_params, &buf,
 425                         GNUTLS_X509_FMT_PEM );
 426                 LDAP_FREE( buf.data );
 427                 if ( rc ) return -1;
 428                 gnutls_certificate_set_dh_params( ctx->cred, ctx->dh_params );
 429         }
 430         return 0;
 431 }
 432
 433 static tls_session *
 434 tlsg_session_new ( tls_ctx * ctx, int is_server )
 435 {
 436         tlsg_ctx *c = (tlsg_ctx *)ctx;
 437         tlsg_session *session;
 438
 439         session = ber_memcalloc ( 1, sizeof (*session) );
 440         if ( !session )
 441                 return NULL;
 442
 443         session->ctx = c;
 444         gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
 445 #ifdef HAVE_CIPHERSUITES
 446         gnutls_priority_set( session->session, c->prios );
 447 #else
 448         gnutls_set_default_priority( session->session );
 449         if ( c->kx_list ) {
 450                 gnutls_kx_set_priority( session->session, c->kx_list );
 451                 gnutls_cipher_set_priority( session->session, c->cipher_list );
 452                 gnutls_mac_set_priority( session->session, c->mac_list );
 453         }
 454 #endif
 455         if ( c->cred )
 456                 gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
 457
 458         if ( is_server ) {
 459                 int flag = 0;
 460                 if ( c->lo->ldo_tls_require_cert ) {
 461                         flag = GNUTLS_CERT_REQUEST;
 462                         if ( c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
 463                                 c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD )
 464                                 flag = GNUTLS_CERT_REQUIRE;
 465                         gnutls_certificate_server_set_request( session->session, flag );
 466                 }
 467         }
 468         return (tls_session *)session;
 469 }
 470
 471 static int
 472 tlsg_session_accept( tls_session *session )
 473 {
 474         tlsg_session *s = (tlsg_session *)session;
 475         int rc;
 476
 477         rc = gnutls_handshake( s->session );
 478         if ( rc == 0 && s->ctx->lo->ldo_tls_require_cert != LDAP_OPT_X_TLS_NEVER ) {
 479                 const gnutls_datum_t *peer_cert_list;
 480                 unsigned int list_size;
 481
 482                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 483                                                 &list_size );
 484                 if ( !peer_cert_list && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_TRY )
 485                         rc = 0;
 486                 else {
 487                         rc = tlsg_cert_verify( s );
 488                         if ( rc && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW )
 489                                 rc = 0;
 490                 }
 491         }
 492         return rc;
 493 }
 494
 495 static int
 496 tlsg_session_connect( LDAP *ld, tls_session *session )
 497 {
 498         return tlsg_session_accept( session);
 499 }
 500
 501 static int
 502 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 503 {
 504         tlsg_session *s = (tlsg_session *)session;
 505
 506         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 507                 return 0;
 508
 509         switch (gnutls_record_get_direction (s->session)) {
 510         case 0:
 511                 sb->sb_trans_needs_read = 1;
 512                 return 1;
 513         case 1:
 514                 sb->sb_trans_needs_write = 1;
 515                 return 1;
 516         }
 517         return 0;
 518 }
 519
 520 static char *
 521 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 522 {
 523         return (char *)gnutls_strerror( rc );
 524 }
 525
 526 static void
 527 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 528 {
 529         BerElementBuffer berbuf;
 530         BerElement *ber = (BerElement *)&berbuf;
 531         ber_tag_t tag;
 532         ber_len_t len;
 533         ber_int_t i;
 534
 535         ber_init2( ber, cert, LBER_USE_DER );
 536         tag = ber_skip_tag( ber, &len );        /* Sequence */
 537         tag = ber_skip_tag( ber, &len );        /* Sequence */
 538         tag = ber_peek_tag( ber, &len );        /* Context + Constructed (version) */
 539         if ( tag == 0xa0 ) {    /* Version is optional */
 540                 tag = ber_skip_tag( ber, &len );
 541                 tag = ber_get_int( ber, &i );   /* Int: Version */
 542         }
 543         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 544         ber_skip_data( ber, len );
 545         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 546         ber_skip_data( ber, len );
 547         if ( !get_subject ) {
 548                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 549         } else {
 550                 tag = ber_skip_tag( ber, &len );
 551                 ber_skip_data( ber, len );
 552                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 553                 ber_skip_data( ber, len );
 554                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 555         }
 556         len = ber_ptrlen( ber );
 557         dn->bv_val = cert->bv_val + len;
 558         dn->bv_len = cert->bv_len - len;
 559 }
 560
 561 static int
 562 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 563 {
 564         tlsg_session *s = (tlsg_session *)session;
 565         const gnutls_datum_t *x;
 566         struct berval bv;
 567
 568         x = gnutls_certificate_get_ours( s->session );
 569
 570         if (!x) return LDAP_INVALID_CREDENTIALS;
 571
 572         bv.bv_val = (char *) x->data;
 573         bv.bv_len = x->size;
 574
 575         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 576         return 0;
 577 }
 578
 579 static int
 580 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 581 {
 582         tlsg_session *s = (tlsg_session *)session;
 583         if ( !s->peer_der_dn.bv_val ) {
 584                 const gnutls_datum_t *peer_cert_list;
 585                 unsigned int list_size;
 586                 struct berval bv;
 587
 588                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 589                                                         &list_size );
 590                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 591
 592                 bv.bv_len = peer_cert_list->size;
 593                 bv.bv_val = (char *) peer_cert_list->data;
 594
 595                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 596         }
 597         *der_dn = s->peer_der_dn;
 598         return 0;
 599 }
 600
 601 /* what kind of hostname were we given? */
 602 #define IS_DNS  0
 603 #define IS_IP4  1
 604 #define IS_IP6  2
 605
 606 #define CN_OID  "2.5.4.3"
 607
 608 static int
 609 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 610 {
 611         tlsg_session *s = (tlsg_session *)session;
 612         int i, ret;
 613         const gnutls_datum_t *peer_cert_list;
 614         unsigned int list_size;
 615         char altname[NI_MAXHOST];
 616         size_t altnamesize;
 617
 618         gnutls_x509_crt_t cert;
 619         const char *name;
 620         char *ptr;
 621         char *domain = NULL;
 622 #ifdef LDAP_PF_INET6
 623         struct in6_addr addr;
 624 #else
 625         struct in_addr addr;
 626 #endif
 627         int len1 = 0, len2 = 0;
 628         int ntype = IS_DNS;
 629
 630         if( ldap_int_hostname &&
 631                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 632         {
 633                 name = ldap_int_hostname;
 634         } else {
 635                 name = name_in;
 636         }
 637
 638         peer_cert_list = gnutls_certificate_get_peers( s->session,
 639                                                 &list_size );
 640         if ( !peer_cert_list ) {
 641                 Debug( LDAP_DEBUG_ANY,
 642                         "TLS: unable to get peer certificate.\n",
 643                         0, 0, 0 );
 644                 /* If this was a fatal condition, things would have
 645                  * aborted long before now.
 646                  */
 647                 return LDAP_SUCCESS;
 648         }
 649         ret = gnutls_x509_crt_init( &cert );
 650         if ( ret < 0 )
 651                 return LDAP_LOCAL_ERROR;
 652         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 653         if ( ret ) {
 654                 gnutls_x509_crt_deinit( cert );
 655                 return LDAP_LOCAL_ERROR;
 656         }
 657
 658 #ifdef LDAP_PF_INET6
 659         if (inet_pton(AF_INET6, name, &addr)) {
 660                 ntype = IS_IP6;
 661         } else
 662 #endif
 663         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 664                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 665         }
 666
 667         if (ntype == IS_DNS) {
 668                 len1 = strlen(name);
 669                 domain = strchr(name, '.');
 670                 if (domain) {
 671                         len2 = len1 - (domain-name);
 672                 }
 673         }
 674
 675         for ( i=0, ret=0; ret >= 0; i++ ) {
 676                 altnamesize = sizeof(altname);
 677                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 678                         altname, &altnamesize, NULL );
 679                 if ( ret < 0 ) break;
 680
 681                 /* ignore empty */
 682                 if ( altnamesize == 0 ) continue;
 683
 684                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 685                         if (ntype != IS_DNS) continue;
 686
 687                         /* Is this an exact match? */
 688                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 689                                 break;
 690                         }
 691
 692                         /* Is this a wildcard match? */
 693                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 694                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 695                         {
 696                                 break;
 697                         }
 698                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 699                         if (ntype == IS_DNS) continue;
 700
 701 #ifdef LDAP_PF_INET6
 702                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 703                                 continue;
 704                         } else
 705 #endif
 706                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 707                                 continue;
 708                         }
 709                         if (!memcmp(altname, &addr, altnamesize)) {
 710                                 break;
 711                         }
 712                 }
 713         }
 714         if ( ret >= 0 ) {
 715                 ret = LDAP_SUCCESS;
 716         } else {
 717                 /* find the last CN */
 718                 i=0;
 719                 do {
 720                         altnamesize = 0;
 721                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 722                                 i, 1, altname, &altnamesize );
 723                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 724                                 i++;
 725                         else
 726                                 break;
 727                 } while ( 1 );
 728
 729                 if ( i ) {
 730                         altnamesize = sizeof(altname);
 731                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 732                                 i-1, 0, altname, &altnamesize );
 733                 }
 734
 735                 if ( ret < 0 ) {
 736                         Debug( LDAP_DEBUG_ANY,
 737                                 "TLS: unable to get common name from peer certificate.\n",
 738                                 0, 0, 0 );
 739                         ret = LDAP_CONNECT_ERROR;
 740                         if ( ld->ld_error ) {
 741                                 LDAP_FREE( ld->ld_error );
 742                         }
 743                         ld->ld_error = LDAP_STRDUP(
 744                                 _("TLS: unable to get CN from peer certificate"));
 745
 746                 } else {
 747                         ret = LDAP_LOCAL_ERROR;
 748                         if ( !len1 ) len1 = strlen( name );
 749                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 750                                 ret = LDAP_SUCCESS;
 751
 752                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 753                                         /* Is this a wildcard match? */
 754                                 if( domain &&
 755                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 756                                         ret = LDAP_SUCCESS;
 757                                 }
 758                         }
 759                 }
 760
 761                 if( ret == LDAP_LOCAL_ERROR ) {
 762                         altname[altnamesize] = '\0';
 763                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 764                                 "common name in certificate (%s).\n",
 765                                 name, altname, 0 );
 766                         ret = LDAP_CONNECT_ERROR;
 767                         if ( ld->ld_error ) {
 768                                 LDAP_FREE( ld->ld_error );
 769                         }
 770                         ld->ld_error = LDAP_STRDUP(
 771                                 _("TLS: hostname does not match CN in peer certificate"));
 772                 }
 773         }
 774         gnutls_x509_crt_deinit( cert );
 775         return ret;
 776 }
 777
 778 static int
 779 tlsg_session_strength( tls_session *session )
 780 {
 781         tlsg_session *s = (tlsg_session *)session;
 782         gnutls_cipher_algorithm_t c;
 783
 784         c = gnutls_cipher_get( s->session );
 785         return gnutls_cipher_get_key_size( c ) * 8;
 786 }
 787
 788 static int
 789 tlsg_session_unique( tls_session *sess, struct berval *buf, int is_server)
 790 {
 791         return 0;
 792 }
 793
 794 /* suites is a string of colon-separated cipher suite names. */
 795 static int
 796 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 797 {
 798 #ifdef HAVE_CIPHERSUITES
 799         const char *err;
 800         return gnutls_priority_init( &ctx->prios, suites, &err );
 801 #else
 802         char *ptr, *end;
 803         int i, j, len, num;
 804         int *list, nkx = 0, ncipher = 0, nmac = 0;
 805         int *kx, *cipher, *mac;
 806
 807         num = 0;
 808         ptr = suites;
 809         do {
 810                 end = strchr(ptr, ':');
 811                 if ( end )
 812                         len = end - ptr;
 813                 else
 814                         len = strlen(ptr);
 815                 for (i=0; i<tlsg_n_ciphers; i++) {
 816                         if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
 817                                 num++;
 818                                 break;
 819                         }
 820                 }
 821                 if ( i == tlsg_n_ciphers ) {
 822                         /* unrecognized cipher suite */
 823                         return -1;
 824                 }
 825                 ptr += len + 1;
 826         } while (end);
 827
 828         /* Space for all 3 lists */
 829         list = LDAP_MALLOC( (num+1) * sizeof(int) * 3 );
 830         if ( !list )
 831                 return -1;
 832         kx = list;
 833         cipher = kx+num+1;
 834         mac = cipher+num+1;
 835
 836         ptr = suites;
 837         do {
 838                 end = strchr(ptr, ':');
 839                 if ( end )
 840                         len = end - ptr;
 841                 else
 842                         len = strlen(ptr);
 843                 for (i=0; i<tlsg_n_ciphers; i++) {
 844                         /* For each cipher suite, insert its algorithms into
 845                          * their respective priority lists. Make sure they
 846                          * only appear once in each list.
 847                          */
 848                         if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
 849                                 for (j=0; j<nkx; j++)
 850                                         if ( kx[j] == tlsg_ciphers[i].kx )
 851                                                 break;
 852                                 if ( j == nkx )
 853                                         kx[nkx++] = tlsg_ciphers[i].kx;
 854                                 for (j=0; j<ncipher; j++)
 855                                         if ( cipher[j] == tlsg_ciphers[i].cipher )
 856                                                 break;
 857                                 if ( j == ncipher )
 858                                         cipher[ncipher++] = tlsg_ciphers[i].cipher;
 859                                 for (j=0; j<nmac; j++)
 860                                         if ( mac[j] == tlsg_ciphers[i].mac )
 861                                                 break;
 862                                 if ( j == nmac )
 863                                         mac[nmac++] = tlsg_ciphers[i].mac;
 864                                 break;
 865                         }
 866                 }
 867                 ptr += len + 1;
 868         } while (end);
 869         kx[nkx] = 0;
 870         cipher[ncipher] = 0;
 871         mac[nmac] = 0;
 872         ctx->kx_list = kx;
 873         ctx->cipher_list = cipher;
 874         ctx->mac_list = mac;
 875         return 0;
 876 #endif
 877 }
 878
 879 /*
 880  * TLS support for LBER Sockbufs
 881  */
 882
 883 struct tls_data {
 884         tlsg_session            *session;
 885         Sockbuf_IO_Desc         *sbiod;
 886 };
 887
 888 static ssize_t
 889 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 890 {
 891         struct tls_data         *p;
 892
 893         if ( buf == NULL || len <= 0 ) return 0;
 894
 895         p = (struct tls_data *)ptr;
 896
 897         if ( p == NULL || p->sbiod == NULL ) {
 898                 return 0;
 899         }
 900
 901         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 902 }
 903
 904 static ssize_t
 905 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 906 {
 907         struct tls_data         *p;
 908
 909         if ( buf == NULL || len <= 0 ) return 0;
 910
 911         p = (struct tls_data *)ptr;
 912
 913         if ( p == NULL || p->sbiod == NULL ) {
 914                 return 0;
 915         }
 916
 917         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 918 }
 919
 920 static int
 921 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 922 {
 923         struct tls_data         *p;
 924         tlsg_session    *session = arg;
 925
 926         assert( sbiod != NULL );
 927
 928         p = LBER_MALLOC( sizeof( *p ) );
 929         if ( p == NULL ) {
 930                 return -1;
 931         }
 932
 933         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 934         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 935         gnutls_transport_set_push_function( session->session, tlsg_send );
 936         p->session = session;
 937         p->sbiod = sbiod;
 938         sbiod->sbiod_pvt = p;
 939         return 0;
 940 }
 941
 942 static int
 943 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 944 {
 945         struct tls_data         *p;
 946
 947         assert( sbiod != NULL );
 948         assert( sbiod->sbiod_pvt != NULL );
 949
 950         p = (struct tls_data *)sbiod->sbiod_pvt;
 951         gnutls_deinit ( p->session->session );
 952         LBER_FREE( p->session );
 953         LBER_FREE( sbiod->sbiod_pvt );
 954         sbiod->sbiod_pvt = NULL;
 955         return 0;
 956 }
 957
 958 static int
 959 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 960 {
 961         struct tls_data         *p;
 962
 963         assert( sbiod != NULL );
 964         assert( sbiod->sbiod_pvt != NULL );
 965
 966         p = (struct tls_data *)sbiod->sbiod_pvt;
 967         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 968         return 0;
 969 }
 970
 971 static int
 972 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 973 {
 974         struct tls_data         *p;
 975
 976         assert( sbiod != NULL );
 977         assert( sbiod->sbiod_pvt != NULL );
 978
 979         p = (struct tls_data *)sbiod->sbiod_pvt;
 980
 981         if ( opt == LBER_SB_OPT_GET_SSL ) {
 982                 *((tlsg_session **)arg) = p->session;
 983                 return 1;
 984
 985         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 986                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 987                         return 1;
 988                 }
 989         }
 990
 991         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 992 }
 993
 994 static ber_slen_t
 995 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
 996 {
 997         struct tls_data         *p;
 998         ber_slen_t              ret;
 999
1000         assert( sbiod != NULL );
1001         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1002
1003         p = (struct tls_data *)sbiod->sbiod_pvt;
1004
1005         ret = gnutls_record_recv ( p->session->session, buf, len );
1006         switch (ret) {
1007         case GNUTLS_E_INTERRUPTED:
1008         case GNUTLS_E_AGAIN:
1009                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
1010                 sock_errset(EWOULDBLOCK);
1011                 ret = 0;
1012                 break;
1013         case GNUTLS_E_REHANDSHAKE:
1014                 for ( ret = gnutls_handshake ( p->session->session );
1015                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
1016                       ret = gnutls_handshake ( p->session->session ) );
1017                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
1018                 ret = 0;
1019                 break;
1020         default:
1021                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
1022         }
1023         return ret;
1024 }
1025
1026 static ber_slen_t
1027 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
1028 {
1029         struct tls_data         *p;
1030         ber_slen_t              ret;
1031
1032         assert( sbiod != NULL );
1033         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1034
1035         p = (struct tls_data *)sbiod->sbiod_pvt;
1036
1037         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
1038
1039         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
1040                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
1041                 sock_errset(EWOULDBLOCK);
1042                 ret = 0;
1043         } else {
1044                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
1045         }
1046         return ret;
1047 }
1048
1049 static Sockbuf_IO tlsg_sbio =
1050 {
1051         tlsg_sb_setup,          /* sbi_setup */
1052         tlsg_sb_remove,         /* sbi_remove */
1053         tlsg_sb_ctrl,           /* sbi_ctrl */
1054         tlsg_sb_read,           /* sbi_read */
1055         tlsg_sb_write,          /* sbi_write */
1056         tlsg_sb_close           /* sbi_close */
1057 };
1058
1059 /* Certs are not automatically varified during the handshake */
1060 static int
1061 tlsg_cert_verify( tlsg_session *ssl )
1062 {
1063         unsigned int status = 0;
1064         int err;
1065         time_t now = time(0);
1066         time_t peertime;
1067
1068         err = gnutls_certificate_verify_peers2( ssl->session, &status );
1069         if ( err < 0 ) {
1070                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
1071                         err,0,0 );
1072                 return -1;
1073         }
1074         if ( status ) {
1075                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
1076                         status, 0,0 );
1077                 return -1;
1078         }
1079         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
1080         if ( peertime == (time_t) -1 ) {
1081                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
1082                         0, 0, 0 );
1083                 return -1;
1084         }
1085         if ( peertime < now ) {
1086                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
1087                         0, 0, 0 );
1088                 return -1;
1089         }
1090         peertime = gnutls_certificate_activation_time_peers( ssl->session );
1091         if ( peertime == (time_t) -1 ) {
1092                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
1093                         0, 0, 0 );
1094                 return -1;
1095         }
1096         if ( peertime > now ) {
1097                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
1098                         0, 0, 0 );
1099                 return -1;
1100         }
1101         return 0;
1102 }
1103
1104 tls_impl ldap_int_tls_impl = {
1105         "GnuTLS",
1106
1107         tlsg_init,
1108         tlsg_destroy,
1109
1110         tlsg_ctx_new,
1111         tlsg_ctx_ref,
1112         tlsg_ctx_free,
1113         tlsg_ctx_init,
1114
1115         tlsg_session_new,
1116         tlsg_session_connect,
1117         tlsg_session_accept,
1118         tlsg_session_upflags,
1119         tlsg_session_errmsg,
1120         tlsg_session_my_dn,
1121         tlsg_session_peer_dn,
1122         tlsg_session_chkhost,
1123         tlsg_session_strength,
1124         tlsg_session_unique,
1125
1126         &tlsg_sbio,
1127
1128 #ifdef LDAP_R_COMPILE
1129         tlsg_thr_init,
1130 #else
1131         NULL,
1132 #endif
1133
1134         0
1135 };
1136
1137 #endif /* HAVE_GNUTLS */