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 #include <gcrypt.h>
  47
  48 #define DH_BITS (1024)
  49
  50 #if LIBGNUTLS_VERSION_NUMBER >= 0x020200
  51 #define HAVE_CIPHERSUITES       1
  52 /* This is a kludge. gcrypt 1.4.x has support. Recent GnuTLS requires gcrypt 1.4.x
  53  * but that dependency isn't reflected in their configure script, resulting in
  54  * build errors on older gcrypt. So, if they have a working build environment,
  55  * assume gcrypt is new enough.
  56  */
  57 #define HAVE_GCRYPT_RAND        1
  58 #else
  59 #undef HAVE_CIPHERSUITES
  60 #undef HAVE_GCRYPT_RAND
  61 #endif
  62
  63 #ifndef HAVE_CIPHERSUITES
  64 /* Versions prior to 2.2.0 didn't handle cipher suites, so we had to
  65  * kludge them ourselves.
  66  */
  67 typedef struct tls_cipher_suite {
  68         const char *name;
  69         gnutls_kx_algorithm_t kx;
  70         gnutls_cipher_algorithm_t cipher;
  71         gnutls_mac_algorithm_t mac;
  72         gnutls_protocol_t version;
  73 } tls_cipher_suite;
  74 #endif
  75
  76 typedef struct tlsg_ctx {
  77         struct ldapoptions *lo;
  78         gnutls_certificate_credentials_t cred;
  79         gnutls_dh_params_t dh_params;
  80         unsigned long verify_depth;
  81         int refcount;
  82 #ifdef HAVE_CIPHERSUITES
  83         gnutls_priority_t prios;
  84 #else
  85         int *kx_list;
  86         int *cipher_list;
  87         int *mac_list;
  88 #endif
  89 #ifdef LDAP_R_COMPILE
  90         ldap_pvt_thread_mutex_t ref_mutex;
  91 #endif
  92 } tlsg_ctx;
  93
  94 typedef struct tlsg_session {
  95         gnutls_session_t session;
  96         tlsg_ctx *ctx;
  97         struct berval peer_der_dn;
  98 } tlsg_session;
  99
 100 #ifndef HAVE_CIPHERSUITES
 101 static tls_cipher_suite *tlsg_ciphers;
 102 static int tlsg_n_ciphers;
 103 #endif
 104
 105 static int tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites );
 106 static int tlsg_cert_verify( tlsg_session *s );
 107
 108 #ifdef LDAP_R_COMPILE
 109
 110 static int
 111 tlsg_mutex_init( void **priv )
 112 {
 113         int err = 0;
 114         ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t ));
 115
 116         if ( !lock )
 117                 err = ENOMEM;
 118         if ( !err ) {
 119                 err = ldap_pvt_thread_mutex_init( lock );
 120                 if ( err )
 121                         LDAP_FREE( lock );
 122                 else
 123                         *priv = lock;
 124         }
 125         return err;
 126 }
 127
 128 static int
 129 tlsg_mutex_destroy( void **lock )
 130 {
 131         int err = ldap_pvt_thread_mutex_destroy( *lock );
 132         LDAP_FREE( *lock );
 133         return err;
 134 }
 135
 136 static int
 137 tlsg_mutex_lock( void **lock )
 138 {
 139         return ldap_pvt_thread_mutex_lock( *lock );
 140 }
 141
 142 static int
 143 tlsg_mutex_unlock( void **lock )
 144 {
 145         return ldap_pvt_thread_mutex_unlock( *lock );
 146 }
 147
 148 static struct gcry_thread_cbs tlsg_thread_cbs = {
 149         GCRY_THREAD_OPTION_USER,
 150         NULL,
 151         tlsg_mutex_init,
 152         tlsg_mutex_destroy,
 153         tlsg_mutex_lock,
 154         tlsg_mutex_unlock,
 155         NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
 156 };
 157
 158 static void
 159 tlsg_thr_init( void )
 160 {
 161         gcry_control (GCRYCTL_SET_THREAD_CBS, &tlsg_thread_cbs);
 162 }
 163 #endif /* LDAP_R_COMPILE */
 164
 165 /*
 166  * Initialize TLS subsystem. Should be called only once.
 167  */
 168 static int
 169 tlsg_init( void )
 170 {
 171 #ifdef HAVE_GCRYPT_RAND
 172         struct ldapoptions *lo = LDAP_INT_GLOBAL_OPT();
 173         if ( lo->ldo_tls_randfile &&
 174                 gcry_control( GCRYCTL_SET_RNDEGD_SOCKET, lo->ldo_tls_randfile )) {
 175                 Debug( LDAP_DEBUG_ANY,
 176                 "TLS: gcry_control GCRYCTL_SET_RNDEGD_SOCKET failed\n",
 177                 0, 0, 0);
 178                 return -1;
 179         }
 180 #endif
 181
 182         gnutls_global_init();
 183
 184 #ifndef HAVE_CIPHERSUITES
 185         /* GNUtls cipher suite handling: The library ought to parse suite
 186          * names for us, but it doesn't. It will return a list of suite names
 187          * that it supports, so we can do parsing ourselves. It ought to tell
 188          * us how long the list is, but it doesn't do that either, so we just
 189          * have to count it manually...
 190          */
 191         {
 192                 int i = 0;
 193                 tls_cipher_suite *ptr, tmp;
 194                 char cs_id[2];
 195
 196                 while ( gnutls_cipher_suite_info( i, cs_id, &tmp.kx, &tmp.cipher,
 197                         &tmp.mac, &tmp.version ))
 198                         i++;
 199                 tlsg_n_ciphers = i;
 200
 201                 /* Store a copy */
 202                 tlsg_ciphers = LDAP_MALLOC(tlsg_n_ciphers * sizeof(tls_cipher_suite));
 203                 if ( !tlsg_ciphers )
 204                         return -1;
 205                 for ( i=0; i<tlsg_n_ciphers; i++ ) {
 206                         tlsg_ciphers[i].name = gnutls_cipher_suite_info( i, cs_id,
 207                                 &tlsg_ciphers[i].kx, &tlsg_ciphers[i].cipher, &tlsg_ciphers[i].mac,
 208                                 &tlsg_ciphers[i].version );
 209                 }
 210         }
 211 #endif
 212         return 0;
 213 }
 214
 215 /*
 216  * Tear down the TLS subsystem. Should only be called once.
 217  */
 218 static void
 219 tlsg_destroy( void )
 220 {
 221 #ifndef HAVE_CIPHERSUITES
 222         LDAP_FREE( tlsg_ciphers );
 223         tlsg_ciphers = NULL;
 224         tlsg_n_ciphers = 0;
 225 #endif
 226         gnutls_global_deinit();
 227 }
 228
 229 static tls_ctx *
 230 tlsg_ctx_new ( struct ldapoptions *lo )
 231 {
 232         tlsg_ctx *ctx;
 233
 234         ctx = ber_memcalloc ( 1, sizeof (*ctx) );
 235         if ( ctx ) {
 236                 ctx->lo = lo;
 237                 if ( gnutls_certificate_allocate_credentials( &ctx->cred )) {
 238                         ber_memfree( ctx );
 239                         return NULL;
 240                 }
 241                 ctx->refcount = 1;
 242 #ifdef HAVE_CIPHERSUITES
 243                 gnutls_priority_init( &ctx->prios, "NORMAL", NULL );
 244 #endif
 245 #ifdef LDAP_R_COMPILE
 246                 ldap_pvt_thread_mutex_init( &ctx->ref_mutex );
 247 #endif
 248         }
 249         return (tls_ctx *)ctx;
 250 }
 251
 252 static void
 253 tlsg_ctx_ref( tls_ctx *ctx )
 254 {
 255         tlsg_ctx *c = (tlsg_ctx *)ctx;
 256         LDAP_MUTEX_LOCK( &c->ref_mutex );
 257         c->refcount++;
 258         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 259 }
 260
 261 static void
 262 tlsg_ctx_free ( tls_ctx *ctx )
 263 {
 264         tlsg_ctx *c = (tlsg_ctx *)ctx;
 265         int refcount;
 266
 267         if ( !c ) return;
 268
 269         LDAP_MUTEX_LOCK( &c->ref_mutex );
 270         refcount = --c->refcount;
 271         LDAP_MUTEX_UNLOCK( &c->ref_mutex );
 272         if ( refcount )
 273                 return;
 274 #ifdef HAVE_CIPHERSUITES
 275         gnutls_priority_deinit( c->prios );
 276 #else
 277         LDAP_FREE( c->kx_list );
 278 #endif
 279         gnutls_certificate_free_credentials( c->cred );
 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 #if GNUTLS_VERSION_NUMBER >= 0x020c00
 372                         unsigned int i;
 373                         for ( i = 1; i<VERIFY_DEPTH; i++ ) {
 374                                 if ( gnutls_certificate_get_issuer( ctx->cred, certs[i-1], &certs[i], 0 ))
 375                                         break;
 376                                 max++;
 377                                 /* If this CA is self-signed, we're done */
 378                                 if ( gnutls_x509_crt_check_issuer( certs[i], certs[i] ))
 379                                         break;
 380                         }
 381 #else
 382                         gnutls_x509_crt_t *cas;
 383                         unsigned int i, j, ncas;
 384
 385                         gnutls_certificate_get_x509_cas( ctx->cred, &cas, &ncas );
 386                         for ( i = 1; i<VERIFY_DEPTH; i++ ) {
 387                                 for ( j = 0; j<ncas; j++ ) {
 388                                         if ( gnutls_x509_crt_check_issuer( certs[i-1], cas[j] )) {
 389                                                 certs[i] = cas[j];
 390                                                 max++;
 391                                                 /* If this CA is self-signed, we're done */
 392                                                 if ( gnutls_x509_crt_check_issuer( cas[j], cas[j] ))
 393                                                         j = ncas;
 394                                                 break;
 395                                         }
 396                                 }
 397                                 /* only continue if we found a CA and it was not self-signed */
 398                                 if ( j == ncas )
 399                                         break;
 400                         }
 401 #endif
 402                 }
 403                 rc = gnutls_certificate_set_x509_key( ctx->cred, certs, max, key );
 404                 if ( rc ) return -1;
 405         } else if ( lo->ldo_tls_certfile || lo->ldo_tls_keyfile ) {
 406                 Debug( LDAP_DEBUG_ANY,
 407                        "TLS: only one of certfile and keyfile specified\n",
 408                        NULL, NULL, NULL );
 409                 return -1;
 410         }
 411
 412         if ( lo->ldo_tls_dhfile ) {
 413                 Debug( LDAP_DEBUG_ANY,
 414                        "TLS: warning: ignoring dhfile\n",
 415                        NULL, NULL, NULL );
 416         }
 417
 418         if ( lo->ldo_tls_crlfile ) {
 419                 rc = gnutls_certificate_set_x509_crl_file(
 420                         ctx->cred,
 421                         lt->lt_crlfile,
 422                         GNUTLS_X509_FMT_PEM );
 423                 if ( rc < 0 ) return -1;
 424                 rc = 0;
 425         }
 426
 427         /* FIXME: ITS#5992 - this should go be configurable,
 428          * and V1 CA certs should be phased out ASAP.
 429          */
 430         gnutls_certificate_set_verify_flags( ctx->cred,
 431                 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT );
 432
 433         if ( is_server ) {
 434                 gnutls_dh_params_init(&ctx->dh_params);
 435                 gnutls_dh_params_generate2(ctx->dh_params, DH_BITS);
 436         }
 437         return 0;
 438 }
 439
 440 static tls_session *
 441 tlsg_session_new ( tls_ctx * ctx, int is_server )
 442 {
 443         tlsg_ctx *c = (tlsg_ctx *)ctx;
 444         tlsg_session *session;
 445
 446         session = ber_memcalloc ( 1, sizeof (*session) );
 447         if ( !session )
 448                 return NULL;
 449
 450         session->ctx = c;
 451         gnutls_init( &session->session, is_server ? GNUTLS_SERVER : GNUTLS_CLIENT );
 452 #ifdef HAVE_CIPHERSUITES
 453         gnutls_priority_set( session->session, c->prios );
 454 #else
 455         gnutls_set_default_priority( session->session );
 456         if ( c->kx_list ) {
 457                 gnutls_kx_set_priority( session->session, c->kx_list );
 458                 gnutls_cipher_set_priority( session->session, c->cipher_list );
 459                 gnutls_mac_set_priority( session->session, c->mac_list );
 460         }
 461 #endif
 462         if ( c->cred )
 463                 gnutls_credentials_set( session->session, GNUTLS_CRD_CERTIFICATE, c->cred );
 464
 465         if ( is_server ) {
 466                 int flag = 0;
 467                 if ( c->lo->ldo_tls_require_cert ) {
 468                         flag = GNUTLS_CERT_REQUEST;
 469                         if ( c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
 470                                 c->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD )
 471                                 flag = GNUTLS_CERT_REQUIRE;
 472                         gnutls_certificate_server_set_request( session->session, flag );
 473                 }
 474         }
 475         return (tls_session *)session;
 476 }
 477
 478 static int
 479 tlsg_session_accept( tls_session *session )
 480 {
 481         tlsg_session *s = (tlsg_session *)session;
 482         int rc;
 483
 484         rc = gnutls_handshake( s->session );
 485         if ( rc == 0 && s->ctx->lo->ldo_tls_require_cert != LDAP_OPT_X_TLS_NEVER ) {
 486                 const gnutls_datum_t *peer_cert_list;
 487                 unsigned int list_size;
 488
 489                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 490                                                 &list_size );
 491                 if ( !peer_cert_list && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_TRY )
 492                         rc = 0;
 493                 else {
 494                         rc = tlsg_cert_verify( s );
 495                         if ( rc && s->ctx->lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW )
 496                                 rc = 0;
 497                 }
 498         }
 499         return rc;
 500 }
 501
 502 static int
 503 tlsg_session_connect( LDAP *ld, tls_session *session )
 504 {
 505         return tlsg_session_accept( session);
 506 }
 507
 508 static int
 509 tlsg_session_upflags( Sockbuf *sb, tls_session *session, int rc )
 510 {
 511         tlsg_session *s = (tlsg_session *)session;
 512
 513         if ( rc != GNUTLS_E_INTERRUPTED && rc != GNUTLS_E_AGAIN )
 514                 return 0;
 515
 516         switch (gnutls_record_get_direction (s->session)) {
 517         case 0:
 518                 sb->sb_trans_needs_read = 1;
 519                 return 1;
 520         case 1:
 521                 sb->sb_trans_needs_write = 1;
 522                 return 1;
 523         }
 524         return 0;
 525 }
 526
 527 static char *
 528 tlsg_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
 529 {
 530         return (char *)gnutls_strerror( rc );
 531 }
 532
 533 static void
 534 tlsg_x509_cert_dn( struct berval *cert, struct berval *dn, int get_subject )
 535 {
 536         BerElementBuffer berbuf;
 537         BerElement *ber = (BerElement *)&berbuf;
 538         ber_tag_t tag;
 539         ber_len_t len;
 540         ber_int_t i;
 541
 542         ber_init2( ber, cert, LBER_USE_DER );
 543         tag = ber_skip_tag( ber, &len );        /* Sequence */
 544         tag = ber_skip_tag( ber, &len );        /* Sequence */
 545         tag = ber_peek_tag( ber, &len );        /* Context + Constructed (version) */
 546         if ( tag == 0xa0 ) {    /* Version is optional */
 547                 tag = ber_skip_tag( ber, &len );
 548                 tag = ber_get_int( ber, &i );   /* Int: Version */
 549         }
 550         tag = ber_skip_tag( ber, &len );        /* Int: Serial (can be longer than ber_int_t) */
 551         ber_skip_data( ber, len );
 552         tag = ber_skip_tag( ber, &len );        /* Sequence: Signature */
 553         ber_skip_data( ber, len );
 554         if ( !get_subject ) {
 555                 tag = ber_peek_tag( ber, &len );        /* Sequence: Issuer DN */
 556         } else {
 557                 tag = ber_skip_tag( ber, &len );
 558                 ber_skip_data( ber, len );
 559                 tag = ber_skip_tag( ber, &len );        /* Sequence: Validity */
 560                 ber_skip_data( ber, len );
 561                 tag = ber_peek_tag( ber, &len );        /* Sequence: Subject DN */
 562         }
 563         len = ber_ptrlen( ber );
 564         dn->bv_val = cert->bv_val + len;
 565         dn->bv_len = cert->bv_len - len;
 566 }
 567
 568 static int
 569 tlsg_session_my_dn( tls_session *session, struct berval *der_dn )
 570 {
 571         tlsg_session *s = (tlsg_session *)session;
 572         const gnutls_datum_t *x;
 573         struct berval bv;
 574
 575         x = gnutls_certificate_get_ours( s->session );
 576
 577         if (!x) return LDAP_INVALID_CREDENTIALS;
 578
 579         bv.bv_val = (char *) x->data;
 580         bv.bv_len = x->size;
 581
 582         tlsg_x509_cert_dn( &bv, der_dn, 1 );
 583         return 0;
 584 }
 585
 586 static int
 587 tlsg_session_peer_dn( tls_session *session, struct berval *der_dn )
 588 {
 589         tlsg_session *s = (tlsg_session *)session;
 590         if ( !s->peer_der_dn.bv_val ) {
 591                 const gnutls_datum_t *peer_cert_list;
 592                 unsigned int list_size;
 593                 struct berval bv;
 594
 595                 peer_cert_list = gnutls_certificate_get_peers( s->session,
 596                                                         &list_size );
 597                 if ( !peer_cert_list ) return LDAP_INVALID_CREDENTIALS;
 598
 599                 bv.bv_len = peer_cert_list->size;
 600                 bv.bv_val = (char *) peer_cert_list->data;
 601
 602                 tlsg_x509_cert_dn( &bv, &s->peer_der_dn, 1 );
 603         }
 604         *der_dn = s->peer_der_dn;
 605         return 0;
 606 }
 607
 608 /* what kind of hostname were we given? */
 609 #define IS_DNS  0
 610 #define IS_IP4  1
 611 #define IS_IP6  2
 612
 613 #define CN_OID  "2.5.4.3"
 614
 615 static int
 616 tlsg_session_chkhost( LDAP *ld, tls_session *session, const char *name_in )
 617 {
 618         tlsg_session *s = (tlsg_session *)session;
 619         int i, ret;
 620         const gnutls_datum_t *peer_cert_list;
 621         unsigned int list_size;
 622         char altname[NI_MAXHOST];
 623         size_t altnamesize;
 624
 625         gnutls_x509_crt_t cert;
 626         const char *name;
 627         char *ptr;
 628         char *domain = NULL;
 629 #ifdef LDAP_PF_INET6
 630         struct in6_addr addr;
 631 #else
 632         struct in_addr addr;
 633 #endif
 634         int len1 = 0, len2 = 0;
 635         int ntype = IS_DNS;
 636
 637         if( ldap_int_hostname &&
 638                 ( !name_in || !strcasecmp( name_in, "localhost" ) ) )
 639         {
 640                 name = ldap_int_hostname;
 641         } else {
 642                 name = name_in;
 643         }
 644
 645         peer_cert_list = gnutls_certificate_get_peers( s->session,
 646                                                 &list_size );
 647         if ( !peer_cert_list ) {
 648                 Debug( LDAP_DEBUG_ANY,
 649                         "TLS: unable to get peer certificate.\n",
 650                         0, 0, 0 );
 651                 /* If this was a fatal condition, things would have
 652                  * aborted long before now.
 653                  */
 654                 return LDAP_SUCCESS;
 655         }
 656         ret = gnutls_x509_crt_init( &cert );
 657         if ( ret < 0 )
 658                 return LDAP_LOCAL_ERROR;
 659         ret = gnutls_x509_crt_import( cert, peer_cert_list, GNUTLS_X509_FMT_DER );
 660         if ( ret ) {
 661                 gnutls_x509_crt_deinit( cert );
 662                 return LDAP_LOCAL_ERROR;
 663         }
 664
 665 #ifdef LDAP_PF_INET6
 666         if (inet_pton(AF_INET6, name, &addr)) {
 667                 ntype = IS_IP6;
 668         } else
 669 #endif
 670         if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
 671                 if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
 672         }
 673
 674         if (ntype == IS_DNS) {
 675                 len1 = strlen(name);
 676                 domain = strchr(name, '.');
 677                 if (domain) {
 678                         len2 = len1 - (domain-name);
 679                 }
 680         }
 681
 682         for ( i=0, ret=0; ret >= 0; i++ ) {
 683                 altnamesize = sizeof(altname);
 684                 ret = gnutls_x509_crt_get_subject_alt_name( cert, i,
 685                         altname, &altnamesize, NULL );
 686                 if ( ret < 0 ) break;
 687
 688                 /* ignore empty */
 689                 if ( altnamesize == 0 ) continue;
 690
 691                 if ( ret == GNUTLS_SAN_DNSNAME ) {
 692                         if (ntype != IS_DNS) continue;
 693
 694                         /* Is this an exact match? */
 695                         if ((len1 == altnamesize) && !strncasecmp(name, altname, len1)) {
 696                                 break;
 697                         }
 698
 699                         /* Is this a wildcard match? */
 700                         if (domain && (altname[0] == '*') && (altname[1] == '.') &&
 701                                 (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2))
 702                         {
 703                                 break;
 704                         }
 705                 } else if ( ret == GNUTLS_SAN_IPADDRESS ) {
 706                         if (ntype == IS_DNS) continue;
 707
 708 #ifdef LDAP_PF_INET6
 709                         if (ntype == IS_IP6 && altnamesize != sizeof(struct in6_addr)) {
 710                                 continue;
 711                         } else
 712 #endif
 713                         if (ntype == IS_IP4 && altnamesize != sizeof(struct in_addr)) {
 714                                 continue;
 715                         }
 716                         if (!memcmp(altname, &addr, altnamesize)) {
 717                                 break;
 718                         }
 719                 }
 720         }
 721         if ( ret >= 0 ) {
 722                 ret = LDAP_SUCCESS;
 723         } else {
 724                 /* find the last CN */
 725                 i=0;
 726                 do {
 727                         altnamesize = 0;
 728                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 729                                 i, 1, altname, &altnamesize );
 730                         if ( ret == GNUTLS_E_SHORT_MEMORY_BUFFER )
 731                                 i++;
 732                         else
 733                                 break;
 734                 } while ( 1 );
 735
 736                 if ( i ) {
 737                         altnamesize = sizeof(altname);
 738                         ret = gnutls_x509_crt_get_dn_by_oid( cert, CN_OID,
 739                                 i-1, 0, altname, &altnamesize );
 740                 }
 741
 742                 if ( ret < 0 ) {
 743                         Debug( LDAP_DEBUG_ANY,
 744                                 "TLS: unable to get common name from peer certificate.\n",
 745                                 0, 0, 0 );
 746                         ret = LDAP_CONNECT_ERROR;
 747                         if ( ld->ld_error ) {
 748                                 LDAP_FREE( ld->ld_error );
 749                         }
 750                         ld->ld_error = LDAP_STRDUP(
 751                                 _("TLS: unable to get CN from peer certificate"));
 752
 753                 } else {
 754                         ret = LDAP_LOCAL_ERROR;
 755                         if ( !len1 ) len1 = strlen( name );
 756                         if ( len1 == altnamesize && strncasecmp(name, altname, altnamesize) == 0 ) {
 757                                 ret = LDAP_SUCCESS;
 758
 759                         } else if (( altname[0] == '*' ) && ( altname[1] == '.' )) {
 760                                         /* Is this a wildcard match? */
 761                                 if( domain &&
 762                                         (len2 == altnamesize-1) && !strncasecmp(domain, &altname[1], len2)) {
 763                                         ret = LDAP_SUCCESS;
 764                                 }
 765                         }
 766                 }
 767
 768                 if( ret == LDAP_LOCAL_ERROR ) {
 769                         altname[altnamesize] = '\0';
 770                         Debug( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
 771                                 "common name in certificate (%s).\n",
 772                                 name, altname, 0 );
 773                         ret = LDAP_CONNECT_ERROR;
 774                         if ( ld->ld_error ) {
 775                                 LDAP_FREE( ld->ld_error );
 776                         }
 777                         ld->ld_error = LDAP_STRDUP(
 778                                 _("TLS: hostname does not match CN in peer certificate"));
 779                 }
 780         }
 781         gnutls_x509_crt_deinit( cert );
 782         return ret;
 783 }
 784
 785 static int
 786 tlsg_session_strength( tls_session *session )
 787 {
 788         tlsg_session *s = (tlsg_session *)session;
 789         gnutls_cipher_algorithm_t c;
 790
 791         c = gnutls_cipher_get( s->session );
 792         return gnutls_cipher_get_key_size( c ) * 8;
 793 }
 794
 795 /* suites is a string of colon-separated cipher suite names. */
 796 static int
 797 tlsg_parse_ciphers( tlsg_ctx *ctx, char *suites )
 798 {
 799 #ifdef HAVE_CIPHERSUITES
 800         const char *err;
 801         int rc = gnutls_priority_init( &ctx->prios, suites, &err );
 802         if ( rc )
 803                 ctx->prios = NULL;
 804         return rc;
 805 #else
 806         char *ptr, *end;
 807         int i, j, len, num;
 808         int *list, nkx = 0, ncipher = 0, nmac = 0;
 809         int *kx, *cipher, *mac;
 810
 811         num = 0;
 812         ptr = suites;
 813         do {
 814                 end = strchr(ptr, ':');
 815                 if ( end )
 816                         len = end - ptr;
 817                 else
 818                         len = strlen(ptr);
 819                 for (i=0; i<tlsg_n_ciphers; i++) {
 820                         if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
 821                                 num++;
 822                                 break;
 823                         }
 824                 }
 825                 if ( i == tlsg_n_ciphers ) {
 826                         /* unrecognized cipher suite */
 827                         return -1;
 828                 }
 829                 ptr += len + 1;
 830         } while (end);
 831
 832         /* Space for all 3 lists */
 833         list = LDAP_MALLOC( (num+1) * sizeof(int) * 3 );
 834         if ( !list )
 835                 return -1;
 836         kx = list;
 837         cipher = kx+num+1;
 838         mac = cipher+num+1;
 839
 840         ptr = suites;
 841         do {
 842                 end = strchr(ptr, ':');
 843                 if ( end )
 844                         len = end - ptr;
 845                 else
 846                         len = strlen(ptr);
 847                 for (i=0; i<tlsg_n_ciphers; i++) {
 848                         /* For each cipher suite, insert its algorithms into
 849                          * their respective priority lists. Make sure they
 850                          * only appear once in each list.
 851                          */
 852                         if ( !strncasecmp( tlsg_ciphers[i].name, ptr, len )) {
 853                                 for (j=0; j<nkx; j++)
 854                                         if ( kx[j] == tlsg_ciphers[i].kx )
 855                                                 break;
 856                                 if ( j == nkx )
 857                                         kx[nkx++] = tlsg_ciphers[i].kx;
 858                                 for (j=0; j<ncipher; j++)
 859                                         if ( cipher[j] == tlsg_ciphers[i].cipher )
 860                                                 break;
 861                                 if ( j == ncipher )
 862                                         cipher[ncipher++] = tlsg_ciphers[i].cipher;
 863                                 for (j=0; j<nmac; j++)
 864                                         if ( mac[j] == tlsg_ciphers[i].mac )
 865                                                 break;
 866                                 if ( j == nmac )
 867                                         mac[nmac++] = tlsg_ciphers[i].mac;
 868                                 break;
 869                         }
 870                 }
 871                 ptr += len + 1;
 872         } while (end);
 873         kx[nkx] = 0;
 874         cipher[ncipher] = 0;
 875         mac[nmac] = 0;
 876         ctx->kx_list = kx;
 877         ctx->cipher_list = cipher;
 878         ctx->mac_list = mac;
 879         return 0;
 880 #endif
 881 }
 882
 883 /*
 884  * TLS support for LBER Sockbufs
 885  */
 886
 887 struct tls_data {
 888         tlsg_session            *session;
 889         Sockbuf_IO_Desc         *sbiod;
 890 };
 891
 892 static ssize_t
 893 tlsg_recv( gnutls_transport_ptr_t ptr, void *buf, size_t len )
 894 {
 895         struct tls_data         *p;
 896
 897         if ( buf == NULL || len <= 0 ) return 0;
 898
 899         p = (struct tls_data *)ptr;
 900
 901         if ( p == NULL || p->sbiod == NULL ) {
 902                 return 0;
 903         }
 904
 905         return LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
 906 }
 907
 908 static ssize_t
 909 tlsg_send( gnutls_transport_ptr_t ptr, const void *buf, size_t len )
 910 {
 911         struct tls_data         *p;
 912
 913         if ( buf == NULL || len <= 0 ) return 0;
 914
 915         p = (struct tls_data *)ptr;
 916
 917         if ( p == NULL || p->sbiod == NULL ) {
 918                 return 0;
 919         }
 920
 921         return LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
 922 }
 923
 924 static int
 925 tlsg_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
 926 {
 927         struct tls_data         *p;
 928         tlsg_session    *session = arg;
 929
 930         assert( sbiod != NULL );
 931
 932         p = LBER_MALLOC( sizeof( *p ) );
 933         if ( p == NULL ) {
 934                 return -1;
 935         }
 936
 937         gnutls_transport_set_ptr( session->session, (gnutls_transport_ptr)p );
 938         gnutls_transport_set_pull_function( session->session, tlsg_recv );
 939         gnutls_transport_set_push_function( session->session, tlsg_send );
 940         p->session = session;
 941         p->sbiod = sbiod;
 942         sbiod->sbiod_pvt = p;
 943         return 0;
 944 }
 945
 946 static int
 947 tlsg_sb_remove( Sockbuf_IO_Desc *sbiod )
 948 {
 949         struct tls_data         *p;
 950
 951         assert( sbiod != NULL );
 952         assert( sbiod->sbiod_pvt != NULL );
 953
 954         p = (struct tls_data *)sbiod->sbiod_pvt;
 955         gnutls_deinit ( p->session->session );
 956         LBER_FREE( p->session );
 957         LBER_FREE( sbiod->sbiod_pvt );
 958         sbiod->sbiod_pvt = NULL;
 959         return 0;
 960 }
 961
 962 static int
 963 tlsg_sb_close( Sockbuf_IO_Desc *sbiod )
 964 {
 965         struct tls_data         *p;
 966
 967         assert( sbiod != NULL );
 968         assert( sbiod->sbiod_pvt != NULL );
 969
 970         p = (struct tls_data *)sbiod->sbiod_pvt;
 971         gnutls_bye ( p->session->session, GNUTLS_SHUT_WR );
 972         return 0;
 973 }
 974
 975 static int
 976 tlsg_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
 977 {
 978         struct tls_data         *p;
 979
 980         assert( sbiod != NULL );
 981         assert( sbiod->sbiod_pvt != NULL );
 982
 983         p = (struct tls_data *)sbiod->sbiod_pvt;
 984
 985         if ( opt == LBER_SB_OPT_GET_SSL ) {
 986                 *((tlsg_session **)arg) = p->session;
 987                 return 1;
 988
 989         } else if ( opt == LBER_SB_OPT_DATA_READY ) {
 990                 if( gnutls_record_check_pending( p->session->session ) > 0 ) {
 991                         return 1;
 992                 }
 993         }
 994
 995         return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
 996 }
 997
 998 static ber_slen_t
 999 tlsg_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
1000 {
1001         struct tls_data         *p;
1002         ber_slen_t              ret;
1003
1004         assert( sbiod != NULL );
1005         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1006
1007         p = (struct tls_data *)sbiod->sbiod_pvt;
1008
1009         ret = gnutls_record_recv ( p->session->session, buf, len );
1010         switch (ret) {
1011         case GNUTLS_E_INTERRUPTED:
1012         case GNUTLS_E_AGAIN:
1013                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
1014                 sock_errset(EWOULDBLOCK);
1015                 ret = 0;
1016                 break;
1017         case GNUTLS_E_REHANDSHAKE:
1018                 for ( ret = gnutls_handshake ( p->session->session );
1019                       ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN;
1020                       ret = gnutls_handshake ( p->session->session ) );
1021                 sbiod->sbiod_sb->sb_trans_needs_read = 1;
1022                 ret = 0;
1023                 break;
1024         default:
1025                 sbiod->sbiod_sb->sb_trans_needs_read = 0;
1026         }
1027         return ret;
1028 }
1029
1030 static ber_slen_t
1031 tlsg_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
1032 {
1033         struct tls_data         *p;
1034         ber_slen_t              ret;
1035
1036         assert( sbiod != NULL );
1037         assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
1038
1039         p = (struct tls_data *)sbiod->sbiod_pvt;
1040
1041         ret = gnutls_record_send ( p->session->session, (char *)buf, len );
1042
1043         if ( ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ) {
1044                 sbiod->sbiod_sb->sb_trans_needs_write = 1;
1045                 sock_errset(EWOULDBLOCK);
1046                 ret = 0;
1047         } else {
1048                 sbiod->sbiod_sb->sb_trans_needs_write = 0;
1049         }
1050         return ret;
1051 }
1052
1053 static Sockbuf_IO tlsg_sbio =
1054 {
1055         tlsg_sb_setup,          /* sbi_setup */
1056         tlsg_sb_remove,         /* sbi_remove */
1057         tlsg_sb_ctrl,           /* sbi_ctrl */
1058         tlsg_sb_read,           /* sbi_read */
1059         tlsg_sb_write,          /* sbi_write */
1060         tlsg_sb_close           /* sbi_close */
1061 };
1062
1063 /* Certs are not automatically varified during the handshake */
1064 static int
1065 tlsg_cert_verify( tlsg_session *ssl )
1066 {
1067         unsigned int status = 0;
1068         int err;
1069         time_t now = time(0);
1070         time_t peertime;
1071
1072         err = gnutls_certificate_verify_peers2( ssl->session, &status );
1073         if ( err < 0 ) {
1074                 Debug( LDAP_DEBUG_ANY,"TLS: gnutls_certificate_verify_peers2 failed %d\n",
1075                         err,0,0 );
1076                 return -1;
1077         }
1078         if ( status ) {
1079                 Debug( LDAP_DEBUG_TRACE,"TLS: peer cert untrusted or revoked (0x%x)\n",
1080                         status, 0,0 );
1081                 return -1;
1082         }
1083         peertime = gnutls_certificate_expiration_time_peers( ssl->session );
1084         if ( peertime == (time_t) -1 ) {
1085                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_expiration_time_peers failed\n",
1086                         0, 0, 0 );
1087                 return -1;
1088         }
1089         if ( peertime < now ) {
1090                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate is expired\n",
1091                         0, 0, 0 );
1092                 return -1;
1093         }
1094         peertime = gnutls_certificate_activation_time_peers( ssl->session );
1095         if ( peertime == (time_t) -1 ) {
1096                 Debug( LDAP_DEBUG_ANY, "TLS: gnutls_certificate_activation_time_peers failed\n",
1097                         0, 0, 0 );
1098                 return -1;
1099         }
1100         if ( peertime > now ) {
1101                 Debug( LDAP_DEBUG_ANY, "TLS: peer certificate not yet active\n",
1102                         0, 0, 0 );
1103                 return -1;
1104         }
1105         return 0;
1106 }
1107
1108 tls_impl ldap_int_tls_impl = {
1109         "GnuTLS",
1110
1111         tlsg_init,
1112         tlsg_destroy,
1113
1114         tlsg_ctx_new,
1115         tlsg_ctx_ref,
1116         tlsg_ctx_free,
1117         tlsg_ctx_init,
1118
1119         tlsg_session_new,
1120         tlsg_session_connect,
1121         tlsg_session_accept,
1122         tlsg_session_upflags,
1123         tlsg_session_errmsg,
1124         tlsg_session_my_dn,
1125         tlsg_session_peer_dn,
1126         tlsg_session_chkhost,
1127         tlsg_session_strength,
1128
1129         &tlsg_sbio,
1130
1131 #ifdef LDAP_R_COMPILE
1132         tlsg_thr_init,
1133 #else
1134         NULL,
1135 #endif
1136
1137         0
1138 };
1139
1140 #endif /* HAVE_GNUTLS */