kdc/pkinit.c

   1 /*
   2  * Copyright (c) 2003 - 2008 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Portions Copyright (c) 2009 Apple Inc. All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "kdc_locl.h"
  37
  38 #ifdef PKINIT
  39
  40 #include <heim_asn1.h>
  41 #include <rfc2459_asn1.h>
  42 #include <cms_asn1.h>
  43 #include <pkinit_asn1.h>
  44
  45 #include <hx509.h>
  46 #include "crypto-headers.h"
  47
  48 struct pk_client_params {
  49     enum krb5_pk_type type;
  50     enum { USE_RSA, USE_DH, USE_ECDH } keyex;
  51     union {
  52         struct {
  53             BIGNUM *public_key;
  54             DH *key;
  55         } dh;
  56 #ifdef HAVE_OPENSSL
  57         struct {
  58             EC_KEY *public_key;
  59             EC_KEY *key;
  60         } ecdh;
  61 #endif
  62     } u;
  63     hx509_cert cert;
  64     unsigned nonce;
  65     EncryptionKey reply_key;
  66     char *dh_group_name;
  67     hx509_peer_info peer;
  68     hx509_certs client_anchors;
  69     hx509_verify_ctx verify_ctx;
  70 };
  71
  72 struct pk_principal_mapping {
  73     unsigned int len;
  74     struct pk_allowed_princ {
  75         krb5_principal principal;
  76         char *subject;
  77     } *val;
  78 };
  79
  80 static struct krb5_pk_identity *kdc_identity;
  81 static struct pk_principal_mapping principal_mappings;
  82 static struct krb5_dh_moduli **moduli;
  83
  84 static struct {
  85     krb5_data data;
  86     time_t expire;
  87     time_t next_update;
  88 } ocsp;
  89
  90 /*
  91  *
  92  */
  93
  94 static krb5_error_code
  95 pk_check_pkauthenticator_win2k(krb5_context context,
  96                                PKAuthenticator_Win2k *a,
  97                                const KDC_REQ *req)
  98 {
  99     krb5_timestamp now;
 100
 101     krb5_timeofday (context, &now);
 102
 103     /* XXX cusec */
 104     if (a->ctime == 0 || abs(a->ctime - now) > context->max_skew) {
 105         krb5_clear_error_message(context);
 106         return KRB5KRB_AP_ERR_SKEW;
 107     }
 108     return 0;
 109 }
 110
 111 static krb5_error_code
 112 pk_check_pkauthenticator(krb5_context context,
 113                          PKAuthenticator *a,
 114                          const KDC_REQ *req)
 115 {
 116     u_char *buf = NULL;
 117     size_t buf_size;
 118     krb5_error_code ret;
 119     size_t len = 0;
 120     krb5_timestamp now;
 121     Checksum checksum;
 122
 123     krb5_timeofday (context, &now);
 124
 125     /* XXX cusec */
 126     if (a->ctime == 0 || abs(a->ctime - now) > context->max_skew) {
 127         krb5_clear_error_message(context);
 128         return KRB5KRB_AP_ERR_SKEW;
 129     }
 130
 131     ASN1_MALLOC_ENCODE(KDC_REQ_BODY, buf, buf_size, &req->req_body, &len, ret);
 132     if (ret) {
 133         krb5_clear_error_message(context);
 134         return ret;
 135     }
 136     if (buf_size != len)
 137         krb5_abortx(context, "Internal error in ASN.1 encoder");
 138
 139     ret = krb5_create_checksum(context,
 140                                NULL,
 141                                0,
 142                                CKSUMTYPE_SHA1,
 143                                buf,
 144                                len,
 145                                &checksum);
 146     free(buf);
 147     if (ret) {
 148         krb5_clear_error_message(context);
 149         return ret;
 150     }
 151
 152     if (a->paChecksum == NULL) {
 153         krb5_clear_error_message(context);
 154         ret = KRB5_KDC_ERR_PA_CHECKSUM_MUST_BE_INCLUDED;
 155         goto out;
 156     }
 157
 158     if (der_heim_octet_string_cmp(a->paChecksum, &checksum.checksum) != 0) {
 159         krb5_clear_error_message(context);
 160         ret = KRB5KRB_ERR_GENERIC;
 161     }
 162
 163 out:
 164     free_Checksum(&checksum);
 165
 166     return ret;
 167 }
 168
 169 void
 170 _kdc_pk_free_client_param(krb5_context context, pk_client_params *cp)
 171 {
 172     if (cp == NULL)
 173         return;
 174     if (cp->cert)
 175         hx509_cert_free(cp->cert);
 176     if (cp->verify_ctx)
 177         hx509_verify_destroy_ctx(cp->verify_ctx);
 178     if (cp->keyex == USE_DH) {
 179         if (cp->u.dh.key)
 180             DH_free(cp->u.dh.key);
 181         if (cp->u.dh.public_key)
 182             BN_free(cp->u.dh.public_key);
 183     }
 184 #ifdef HAVE_OPENSSL
 185     if (cp->keyex == USE_ECDH) {
 186         if (cp->u.ecdh.key)
 187             EC_KEY_free(cp->u.ecdh.key);
 188         if (cp->u.ecdh.public_key)
 189             EC_KEY_free(cp->u.ecdh.public_key);
 190     }
 191 #endif
 192     krb5_free_keyblock_contents(context, &cp->reply_key);
 193     if (cp->dh_group_name)
 194         free(cp->dh_group_name);
 195     if (cp->peer)
 196         hx509_peer_info_free(cp->peer);
 197     if (cp->client_anchors)
 198         hx509_certs_free(&cp->client_anchors);
 199     memset(cp, 0, sizeof(*cp));
 200     free(cp);
 201 }
 202
 203 static krb5_error_code
 204 generate_dh_keyblock(krb5_context context,
 205                      pk_client_params *client_params,
 206                      krb5_enctype enctype)
 207 {
 208     unsigned char *dh_gen_key = NULL;
 209     krb5_keyblock key;
 210     krb5_error_code ret;
 211     size_t dh_gen_keylen, size;
 212
 213     memset(&key, 0, sizeof(key));
 214
 215     if (client_params->keyex == USE_DH) {
 216
 217         if (client_params->u.dh.public_key == NULL) {
 218             ret = KRB5KRB_ERR_GENERIC;
 219             krb5_set_error_message(context, ret, "public_key");
 220             goto out;
 221         }
 222
 223         if (!DH_generate_key(client_params->u.dh.key)) {
 224             ret = KRB5KRB_ERR_GENERIC;
 225             krb5_set_error_message(context, ret,
 226                                    "Can't generate Diffie-Hellman keys");
 227             goto out;
 228         }
 229
 230         size = DH_size(client_params->u.dh.key);
 231
 232         dh_gen_key = malloc(size);
 233         if (dh_gen_key == NULL) {
 234             ret = ENOMEM;
 235             krb5_set_error_message(context, ret, "malloc: out of memory");
 236             goto out;
 237         }
 238
 239         dh_gen_keylen = DH_compute_key(dh_gen_key,client_params->u.dh.public_key, client_params->u.dh.key);
 240         if (dh_gen_keylen == (size_t)-1) {
 241             ret = KRB5KRB_ERR_GENERIC;
 242             krb5_set_error_message(context, ret,
 243                                    "Can't compute Diffie-Hellman key");
 244             goto out;
 245         }
 246         if (dh_gen_keylen < size) {
 247             size -= dh_gen_keylen;
 248             memmove(dh_gen_key + size, dh_gen_key, dh_gen_keylen);
 249             memset(dh_gen_key, 0, size);
 250         }
 251
 252         ret = 0;
 253 #ifdef HAVE_OPENSSL
 254     } else if (client_params->keyex == USE_ECDH) {
 255
 256         if (client_params->u.ecdh.public_key == NULL) {
 257             ret = KRB5KRB_ERR_GENERIC;
 258             krb5_set_error_message(context, ret, "public_key");
 259             goto out;
 260         }
 261
 262         client_params->u.ecdh.key = EC_KEY_new();
 263         if (client_params->u.ecdh.key == NULL) {
 264             ret = ENOMEM;
 265             goto out;
 266         }
 267         EC_KEY_set_group(client_params->u.ecdh.key,
 268                          EC_KEY_get0_group(client_params->u.ecdh.public_key));
 269
 270         if (EC_KEY_generate_key(client_params->u.ecdh.key) != 1) {
 271             ret = ENOMEM;
 272             goto out;
 273         }
 274
 275         size = (EC_GROUP_get_degree(EC_KEY_get0_group(client_params->u.ecdh.key)) + 7) / 8;
 276         dh_gen_key = malloc(size);
 277         if (dh_gen_key == NULL) {
 278             ret = ENOMEM;
 279             krb5_set_error_message(context, ret,
 280                                    N_("malloc: out of memory", ""));
 281             goto out;
 282         }
 283
 284         dh_gen_keylen = ECDH_compute_key(dh_gen_key, size,
 285                                          EC_KEY_get0_public_key(client_params->u.ecdh.public_key),
 286                                          client_params->u.ecdh.key, NULL);
 287
 288 #endif /* HAVE_OPENSSL */
 289     } else {
 290         ret = KRB5KRB_ERR_GENERIC;
 291         krb5_set_error_message(context, ret,
 292                                "Diffie-Hellman not selected keys");
 293         goto out;
 294     }
 295
 296     ret = _krb5_pk_octetstring2key(context,
 297                                    enctype,
 298                                    dh_gen_key, dh_gen_keylen,
 299                                    NULL, NULL,
 300                                    &client_params->reply_key);
 301
 302  out:
 303     if (dh_gen_key)
 304         free(dh_gen_key);
 305     if (key.keyvalue.data)
 306         krb5_free_keyblock_contents(context, &key);
 307
 308     return ret;
 309 }
 310
 311 static BIGNUM *
 312 integer_to_BN(krb5_context context, const char *field, heim_integer *f)
 313 {
 314     BIGNUM *bn;
 315
 316     bn = BN_bin2bn((const unsigned char *)f->data, f->length, NULL);
 317     if (bn == NULL) {
 318         krb5_set_error_message(context, KRB5_BADMSGTYPE,
 319                                "PKINIT: parsing BN failed %s", field);
 320         return NULL;
 321     }
 322     BN_set_negative(bn, f->negative);
 323     return bn;
 324 }
 325
 326 static krb5_error_code
 327 get_dh_param(krb5_context context,
 328              krb5_kdc_configuration *config,
 329              SubjectPublicKeyInfo *dh_key_info,
 330              pk_client_params *client_params)
 331 {
 332     DomainParameters dhparam;
 333     DH *dh = NULL;
 334     krb5_error_code ret;
 335
 336     memset(&dhparam, 0, sizeof(dhparam));
 337
 338     if ((dh_key_info->subjectPublicKey.length % 8) != 0) {
 339         ret = KRB5_BADMSGTYPE;
 340         krb5_set_error_message(context, ret,
 341                                "PKINIT: subjectPublicKey not aligned "
 342                                "to 8 bit boundary");
 343         goto out;
 344     }
 345
 346     if (dh_key_info->algorithm.parameters == NULL) {
 347         krb5_set_error_message(context, KRB5_BADMSGTYPE,
 348                                "PKINIT missing algorithm parameter "
 349                               "in clientPublicValue");
 350         return KRB5_BADMSGTYPE;
 351     }
 352
 353     ret = decode_DomainParameters(dh_key_info->algorithm.parameters->data,
 354                                   dh_key_info->algorithm.parameters->length,
 355                                   &dhparam,
 356                                   NULL);
 357     if (ret) {
 358         krb5_set_error_message(context, ret, "Can't decode algorithm "
 359                                "parameters in clientPublicValue");
 360         goto out;
 361     }
 362
 363     ret = _krb5_dh_group_ok(context, config->pkinit_dh_min_bits,
 364                             &dhparam.p, &dhparam.g, dhparam.q, moduli,
 365                             &client_params->dh_group_name);
 366     if (ret) {
 367         /* XXX send back proposal of better group */
 368         goto out;
 369     }
 370
 371     dh = DH_new();
 372     if (dh == NULL) {
 373         ret = ENOMEM;
 374         krb5_set_error_message(context, ret, "Cannot create DH structure");
 375         goto out;
 376     }
 377     ret = KRB5_BADMSGTYPE;
 378     dh->p = integer_to_BN(context, "DH prime", &dhparam.p);
 379     if (dh->p == NULL)
 380         goto out;
 381     dh->g = integer_to_BN(context, "DH base", &dhparam.g);
 382     if (dh->g == NULL)
 383         goto out;
 384
 385     if (dhparam.q) {
 386         dh->q = integer_to_BN(context, "DH p-1 factor", dhparam.q);
 387         if (dh->g == NULL)
 388             goto out;
 389     }
 390
 391     {
 392         heim_integer glue;
 393         size_t size;
 394
 395         ret = decode_DHPublicKey(dh_key_info->subjectPublicKey.data,
 396                                  dh_key_info->subjectPublicKey.length / 8,
 397                                  &glue,
 398                                  &size);
 399         if (ret) {
 400             krb5_clear_error_message(context);
 401             return ret;
 402         }
 403
 404         client_params->u.dh.public_key = integer_to_BN(context,
 405                                                        "subjectPublicKey",
 406                                                        &glue);
 407         der_free_heim_integer(&glue);
 408         if (client_params->u.dh.public_key == NULL) {
 409             ret = KRB5_BADMSGTYPE;
 410             goto out;
 411         }
 412     }
 413
 414     client_params->u.dh.key = dh;
 415     dh = NULL;
 416     ret = 0;
 417
 418  out:
 419     if (dh)
 420         DH_free(dh);
 421     free_DomainParameters(&dhparam);
 422     return ret;
 423 }
 424
 425 #ifdef HAVE_OPENSSL
 426
 427 static krb5_error_code
 428 get_ecdh_param(krb5_context context,
 429                krb5_kdc_configuration *config,
 430                SubjectPublicKeyInfo *dh_key_info,
 431                pk_client_params *client_params)
 432 {
 433     ECParameters ecp;
 434     EC_KEY *public = NULL;
 435     krb5_error_code ret;
 436     const unsigned char *p;
 437     size_t len;
 438     int nid;
 439
 440     if (dh_key_info->algorithm.parameters == NULL) {
 441         krb5_set_error_message(context, KRB5_BADMSGTYPE,
 442                                "PKINIT missing algorithm parameter "
 443                                "in clientPublicValue");
 444         return KRB5_BADMSGTYPE;
 445     }
 446
 447     memset(&ecp, 0, sizeof(ecp));
 448
 449     ret = decode_ECParameters(dh_key_info->algorithm.parameters->data,
 450                               dh_key_info->algorithm.parameters->length, &ecp, &len);
 451     if (ret)
 452         goto out;
 453
 454     if (ecp.element != choice_ECParameters_namedCurve) {
 455         ret = KRB5_BADMSGTYPE;
 456         goto out;
 457     }
 458
 459     if (der_heim_oid_cmp(&ecp.u.namedCurve, &asn1_oid_id_ec_group_secp256r1) == 0)
 460         nid = NID_X9_62_prime256v1;
 461     else {
 462         ret = KRB5_BADMSGTYPE;
 463         goto out;
 464     }
 465
 466     /* XXX verify group is ok */
 467
 468     public = EC_KEY_new_by_curve_name(nid);
 469
 470     p = dh_key_info->subjectPublicKey.data;
 471     len = dh_key_info->subjectPublicKey.length / 8;
 472     if (o2i_ECPublicKey(&public, &p, len) == NULL) {
 473         ret = KRB5_BADMSGTYPE;
 474         krb5_set_error_message(context, ret,
 475                                "PKINIT failed to decode ECDH key");
 476         goto out;
 477     }
 478     client_params->u.ecdh.public_key = public;
 479     public = NULL;
 480
 481  out:
 482     if (public)
 483         EC_KEY_free(public);
 484     free_ECParameters(&ecp);
 485     return ret;
 486 }
 487
 488 #endif /* HAVE_OPENSSL */
 489
 490 krb5_error_code
 491 _kdc_pk_rd_padata(krb5_context context,
 492                   krb5_kdc_configuration *config,
 493                   const KDC_REQ *req,
 494                   const PA_DATA *pa,
 495                   hdb_entry_ex *client,
 496                   pk_client_params **ret_params)
 497 {
 498     pk_client_params *cp;
 499     krb5_error_code ret;
 500     heim_oid eContentType = { 0, NULL }, contentInfoOid = { 0, NULL };
 501     krb5_data eContent = { 0, NULL };
 502     krb5_data signed_content = { 0, NULL };
 503     const char *type = "unknown type";
 504     hx509_certs trust_anchors;
 505     int have_data = 0;
 506     const HDB_Ext_PKINIT_cert *pc;
 507
 508     *ret_params = NULL;
 509
 510     if (!config->enable_pkinit) {
 511         kdc_log(context, config, 0, "PK-INIT request but PK-INIT not enabled");
 512         krb5_clear_error_message(context);
 513         return 0;
 514     }
 515
 516     cp = calloc(1, sizeof(*cp));
 517     if (cp == NULL) {
 518         krb5_clear_error_message(context);
 519         ret = ENOMEM;
 520         goto out;
 521     }
 522
 523     ret = hx509_certs_init(context->hx509ctx,
 524                            "MEMORY:trust-anchors",
 525                            0, NULL, &trust_anchors);
 526     if (ret) {
 527         krb5_set_error_message(context, ret, "failed to create trust anchors");
 528         goto out;
 529     }
 530
 531     ret = hx509_certs_merge(context->hx509ctx, trust_anchors,
 532                             kdc_identity->anchors);
 533     if (ret) {
 534         hx509_certs_free(&trust_anchors);
 535         krb5_set_error_message(context, ret, "failed to create verify context");
 536         goto out;
 537     }
 538
 539     /* Add any registered certificates for this client as trust anchors */
 540     ret = hdb_entry_get_pkinit_cert(&client->entry, &pc);
 541     if (ret == 0 && pc != NULL) {
 542         hx509_cert cert;
 543         unsigned int i;
 544
 545         for (i = 0; i < pc->len; i++) {
 546             cert = hx509_cert_init_data(context->hx509ctx,
 547                                         pc->val[i].cert.data,
 548                                         pc->val[i].cert.length,
 549                                         NULL);
 550             if (cert == NULL)
 551                 continue;
 552             hx509_certs_add(context->hx509ctx, trust_anchors, cert);
 553             hx509_cert_free(cert);
 554         }
 555     }
 556
 557     ret = hx509_verify_init_ctx(context->hx509ctx, &cp->verify_ctx);
 558     if (ret) {
 559         hx509_certs_free(&trust_anchors);
 560         krb5_set_error_message(context, ret, "failed to create verify context");
 561         goto out;
 562     }
 563
 564     hx509_verify_set_time(cp->verify_ctx, kdc_time);
 565     hx509_verify_attach_anchors(cp->verify_ctx, trust_anchors);
 566     hx509_certs_free(&trust_anchors);
 567
 568     if (config->pkinit_allow_proxy_certs)
 569         hx509_verify_set_proxy_certificate(cp->verify_ctx, 1);
 570
 571     if (pa->padata_type == KRB5_PADATA_PK_AS_REQ_WIN) {
 572         PA_PK_AS_REQ_Win2k r;
 573
 574         type = "PK-INIT-Win2k";
 575
 576         if (req->req_body.kdc_options.request_anonymous) {
 577             ret = KRB5_KDC_ERR_PUBLIC_KEY_ENCRYPTION_NOT_SUPPORTED;
 578             krb5_set_error_message(context, ret,
 579                                    "Anon not supported in RSA mode");
 580             goto out;
 581         }
 582
 583         ret = decode_PA_PK_AS_REQ_Win2k(pa->padata_value.data,
 584                                         pa->padata_value.length,
 585                                         &r,
 586                                         NULL);
 587         if (ret) {
 588             krb5_set_error_message(context, ret, "Can't decode "
 589                                    "PK-AS-REQ-Win2k: %d", ret);
 590             goto out;
 591         }
 592
 593         ret = hx509_cms_unwrap_ContentInfo(&r.signed_auth_pack,
 594                                            &contentInfoOid,
 595                                            &signed_content,
 596                                            &have_data);
 597         free_PA_PK_AS_REQ_Win2k(&r);
 598         if (ret) {
 599             krb5_set_error_message(context, ret,
 600                                    "Can't unwrap ContentInfo(win): %d", ret);
 601             goto out;
 602         }
 603
 604     } else if (pa->padata_type == KRB5_PADATA_PK_AS_REQ) {
 605         PA_PK_AS_REQ r;
 606
 607         type = "PK-INIT-IETF";
 608
 609         ret = decode_PA_PK_AS_REQ(pa->padata_value.data,
 610                                   pa->padata_value.length,
 611                                   &r,
 612                                   NULL);
 613         if (ret) {
 614             krb5_set_error_message(context, ret,
 615                                    "Can't decode PK-AS-REQ: %d", ret);
 616             goto out;
 617         }
 618
 619         /* XXX look at r.kdcPkId */
 620         if (r.trustedCertifiers) {
 621             ExternalPrincipalIdentifiers *edi = r.trustedCertifiers;
 622             unsigned int i, maxedi;
 623
 624             ret = hx509_certs_init(context->hx509ctx,
 625                                    "MEMORY:client-anchors",
 626                                    0, NULL,
 627                                    &cp->client_anchors);
 628             if (ret) {
 629                 krb5_set_error_message(context, ret,
 630                                        "Can't allocate client anchors: %d",
 631                                        ret);
 632                 goto out;
 633
 634             }
 635             /*
 636              * If the client sent more then 10 EDI, don't bother
 637              * looking more then 10 of performance reasons.
 638              */
 639             maxedi = edi->len;
 640             if (maxedi > 10)
 641                 maxedi = 10;
 642             for (i = 0; i < maxedi; i++) {
 643                 IssuerAndSerialNumber iasn;
 644                 hx509_query *q;
 645                 hx509_cert cert;
 646                 size_t size;
 647
 648                 if (edi->val[i].issuerAndSerialNumber == NULL)
 649                     continue;
 650
 651                 ret = hx509_query_alloc(context->hx509ctx, &q);
 652                 if (ret) {
 653                     krb5_set_error_message(context, ret,
 654                                           "Failed to allocate hx509_query");
 655                     goto out;
 656                 }
 657
 658                 ret = decode_IssuerAndSerialNumber(edi->val[i].issuerAndSerialNumber->data,
 659                                                    edi->val[i].issuerAndSerialNumber->length,
 660                                                    &iasn,
 661                                                    &size);
 662                 if (ret) {
 663                     hx509_query_free(context->hx509ctx, q);
 664                     continue;
 665                 }
 666                 ret = hx509_query_match_issuer_serial(q, &iasn.issuer, &iasn.serialNumber);
 667                 free_IssuerAndSerialNumber(&iasn);
 668                 if (ret) {
 669                     hx509_query_free(context->hx509ctx, q);
 670                     continue;
 671                 }
 672
 673                 ret = hx509_certs_find(context->hx509ctx,
 674                                        kdc_identity->certs,
 675                                        q,
 676                                        &cert);
 677                 hx509_query_free(context->hx509ctx, q);
 678                 if (ret)
 679                     continue;
 680                 hx509_certs_add(context->hx509ctx,
 681                                 cp->client_anchors, cert);
 682                 hx509_cert_free(cert);
 683             }
 684         }
 685
 686         ret = hx509_cms_unwrap_ContentInfo(&r.signedAuthPack,
 687                                            &contentInfoOid,
 688                                            &signed_content,
 689                                            &have_data);
 690         free_PA_PK_AS_REQ(&r);
 691         if (ret) {
 692             krb5_set_error_message(context, ret,
 693                                    "Can't unwrap ContentInfo: %d", ret);
 694             goto out;
 695         }
 696
 697     } else {
 698         krb5_clear_error_message(context);
 699         ret = KRB5KDC_ERR_PADATA_TYPE_NOSUPP;
 700         goto out;
 701     }
 702
 703     ret = der_heim_oid_cmp(&contentInfoOid, &asn1_oid_id_pkcs7_signedData);
 704     if (ret != 0) {
 705         ret = KRB5KRB_ERR_GENERIC;
 706         krb5_set_error_message(context, ret,
 707                                "PK-AS-REQ-Win2k invalid content type oid");
 708         goto out;
 709     }
 710
 711     if (!have_data) {
 712         ret = KRB5KRB_ERR_GENERIC;
 713         krb5_set_error_message(context, ret,
 714                               "PK-AS-REQ-Win2k no signed auth pack");
 715         goto out;
 716     }
 717
 718     {
 719         hx509_certs signer_certs;
 720         int flags = HX509_CMS_VS_ALLOW_DATA_OID_MISMATCH; /* BTMM */
 721
 722         if (req->req_body.kdc_options.request_anonymous)
 723             flags |= HX509_CMS_VS_ALLOW_ZERO_SIGNER;
 724
 725         ret = hx509_cms_verify_signed(context->hx509ctx,
 726                                       cp->verify_ctx,
 727                                       flags,
 728                                       signed_content.data,
 729                                       signed_content.length,
 730                                       NULL,
 731                                       kdc_identity->certpool,
 732                                       &eContentType,
 733                                       &eContent,
 734                                       &signer_certs);
 735         if (ret) {
 736             char *s = hx509_get_error_string(context->hx509ctx, ret);
 737             krb5_warnx(context, "PKINIT: failed to verify signature: %s: %d",
 738                        s, ret);
 739             free(s);
 740             goto out;
 741         }
 742
 743         if (signer_certs) {
 744             ret = hx509_get_one_cert(context->hx509ctx, signer_certs,
 745                                      &cp->cert);
 746             hx509_certs_free(&signer_certs);
 747         }
 748         if (ret)
 749             goto out;
 750     }
 751
 752     /* Signature is correct, now verify the signed message */
 753     if (der_heim_oid_cmp(&eContentType, &asn1_oid_id_pkcs7_data) != 0 &&
 754         der_heim_oid_cmp(&eContentType, &asn1_oid_id_pkauthdata) != 0)
 755     {
 756         ret = KRB5_BADMSGTYPE;
 757         krb5_set_error_message(context, ret, "got wrong oid for pkauthdata");
 758         goto out;
 759     }
 760
 761     if (pa->padata_type == KRB5_PADATA_PK_AS_REQ_WIN) {
 762         AuthPack_Win2k ap;
 763
 764         ret = decode_AuthPack_Win2k(eContent.data,
 765                                     eContent.length,
 766                                     &ap,
 767                                     NULL);
 768         if (ret) {
 769             krb5_set_error_message(context, ret,
 770                                    "Can't decode AuthPack: %d", ret);
 771             goto out;
 772         }
 773
 774         ret = pk_check_pkauthenticator_win2k(context,
 775                                              &ap.pkAuthenticator,
 776                                              req);
 777         if (ret) {
 778             free_AuthPack_Win2k(&ap);
 779             goto out;
 780         }
 781
 782         cp->type = PKINIT_WIN2K;
 783         cp->nonce = ap.pkAuthenticator.nonce;
 784
 785         if (ap.clientPublicValue) {
 786             ret = KRB5KRB_ERR_GENERIC;
 787             krb5_set_error_message(context, ret,
 788                                    "DH not supported for windows");
 789             goto out;
 790         }
 791         free_AuthPack_Win2k(&ap);
 792
 793     } else if (pa->padata_type == KRB5_PADATA_PK_AS_REQ) {
 794         AuthPack ap;
 795
 796         ret = decode_AuthPack(eContent.data,
 797                               eContent.length,
 798                               &ap,
 799                               NULL);
 800         if (ret) {
 801             krb5_set_error_message(context, ret,
 802                                    "Can't decode AuthPack: %d", ret);
 803             free_AuthPack(&ap);
 804             goto out;
 805         }
 806
 807         if (req->req_body.kdc_options.request_anonymous &&
 808             ap.clientPublicValue == NULL) {
 809             free_AuthPack(&ap);
 810             ret = KRB5_KDC_ERR_PUBLIC_KEY_ENCRYPTION_NOT_SUPPORTED;
 811             krb5_set_error_message(context, ret,
 812                                    "Anon not supported in RSA mode");
 813             goto out;
 814         }
 815
 816         ret = pk_check_pkauthenticator(context,
 817                                        &ap.pkAuthenticator,
 818                                        req);
 819         if (ret) {
 820             free_AuthPack(&ap);
 821             goto out;
 822         }
 823
 824         cp->type = PKINIT_27;
 825         cp->nonce = ap.pkAuthenticator.nonce;
 826
 827         if (ap.clientPublicValue) {
 828             if (der_heim_oid_cmp(&ap.clientPublicValue->algorithm.algorithm, &asn1_oid_id_dhpublicnumber) == 0) {
 829                 cp->keyex = USE_DH;
 830                 ret = get_dh_param(context, config,
 831                                    ap.clientPublicValue, cp);
 832 #ifdef HAVE_OPENSSL
 833             } else if (der_heim_oid_cmp(&ap.clientPublicValue->algorithm.algorithm, &asn1_oid_id_ecPublicKey) == 0) {
 834                 cp->keyex = USE_ECDH;
 835                 ret = get_ecdh_param(context, config,
 836                                      ap.clientPublicValue, cp);
 837 #endif /* HAVE_OPENSSL */
 838             } else {
 839                 ret = KRB5_BADMSGTYPE;
 840                 krb5_set_error_message(context, ret, "PKINIT unknown DH mechanism");
 841             }
 842             if (ret) {
 843                 free_AuthPack(&ap);
 844                 goto out;
 845             }
 846         } else
 847             cp->keyex = USE_RSA;
 848
 849         ret = hx509_peer_info_alloc(context->hx509ctx,
 850                                         &cp->peer);
 851         if (ret) {
 852             free_AuthPack(&ap);
 853             goto out;
 854         }
 855
 856         if (ap.supportedCMSTypes) {
 857             ret = hx509_peer_info_set_cms_algs(context->hx509ctx,
 858                                                cp->peer,
 859                                                ap.supportedCMSTypes->val,
 860                                                ap.supportedCMSTypes->len);
 861             if (ret) {
 862                 free_AuthPack(&ap);
 863                 goto out;
 864             }
 865         } else {
 866             /* assume old client */
 867             hx509_peer_info_add_cms_alg(context->hx509ctx, cp->peer,
 868                                         hx509_crypto_des_rsdi_ede3_cbc());
 869             hx509_peer_info_add_cms_alg(context->hx509ctx, cp->peer,
 870                                         hx509_signature_rsa_with_sha1());
 871             hx509_peer_info_add_cms_alg(context->hx509ctx, cp->peer,
 872                                         hx509_signature_sha1());
 873         }
 874         free_AuthPack(&ap);
 875     } else
 876         krb5_abortx(context, "internal pkinit error");
 877
 878     kdc_log(context, config, 0, "PK-INIT request of type %s", type);
 879
 880 out:
 881     if (ret)
 882         krb5_warn(context, ret, "PKINIT");
 883
 884     if (signed_content.data)
 885         free(signed_content.data);
 886     krb5_data_free(&eContent);
 887     der_free_oid(&eContentType);
 888     der_free_oid(&contentInfoOid);
 889     if (ret) {
 890         _kdc_pk_free_client_param(context, cp);
 891     } else
 892         *ret_params = cp;
 893     return ret;
 894 }
 895
 896 /*
 897  *
 898  */
 899
 900 static krb5_error_code
 901 BN_to_integer(krb5_context context, BIGNUM *bn, heim_integer *integer)
 902 {
 903     integer->length = BN_num_bytes(bn);
 904     integer->data = malloc(integer->length);
 905     if (integer->data == NULL) {
 906         krb5_clear_error_message(context);
 907         return ENOMEM;
 908     }
 909     BN_bn2bin(bn, integer->data);
 910     integer->negative = BN_is_negative(bn);
 911     return 0;
 912 }
 913
 914 static krb5_error_code
 915 pk_mk_pa_reply_enckey(krb5_context context,
 916                       krb5_kdc_configuration *config,
 917                       pk_client_params *cp,
 918                       const KDC_REQ *req,
 919                       const krb5_data *req_buffer,
 920                       krb5_keyblock *reply_key,
 921                       ContentInfo *content_info,
 922                       hx509_cert *kdc_cert)
 923 {
 924     const heim_oid *envelopedAlg = NULL, *sdAlg = NULL, *evAlg = NULL;
 925     krb5_error_code ret;
 926     krb5_data buf, signed_data;
 927     size_t size = 0;
 928     int do_win2k = 0;
 929
 930     krb5_data_zero(&buf);
 931     krb5_data_zero(&signed_data);
 932
 933     *kdc_cert = NULL;
 934
 935     /*
 936      * If the message client is a win2k-type but it send pa data
 937      * 09-binding it expects a IETF (checksum) reply so there can be
 938      * no replay attacks.
 939      */
 940
 941     switch (cp->type) {
 942     case PKINIT_WIN2K: {
 943         int i = 0;
 944         if (_kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_09_BINDING) == NULL
 945             && config->pkinit_require_binding == 0)
 946         {
 947             do_win2k = 1;
 948         }
 949         sdAlg = &asn1_oid_id_pkcs7_data;
 950         evAlg = &asn1_oid_id_pkcs7_data;
 951         envelopedAlg = &asn1_oid_id_rsadsi_des_ede3_cbc;
 952         break;
 953     }
 954     case PKINIT_27:
 955         sdAlg = &asn1_oid_id_pkrkeydata;
 956         evAlg = &asn1_oid_id_pkcs7_signedData;
 957         break;
 958     default:
 959         krb5_abortx(context, "internal pkinit error");
 960     }
 961
 962     if (do_win2k) {
 963         ReplyKeyPack_Win2k kp;
 964         memset(&kp, 0, sizeof(kp));
 965
 966         ret = copy_EncryptionKey(reply_key, &kp.replyKey);
 967         if (ret) {
 968             krb5_clear_error_message(context);
 969             goto out;
 970         }
 971         kp.nonce = cp->nonce;
 972
 973         ASN1_MALLOC_ENCODE(ReplyKeyPack_Win2k,
 974                            buf.data, buf.length,
 975                            &kp, &size,ret);
 976         free_ReplyKeyPack_Win2k(&kp);
 977     } else {
 978         krb5_crypto ascrypto;
 979         ReplyKeyPack kp;
 980         memset(&kp, 0, sizeof(kp));
 981
 982         ret = copy_EncryptionKey(reply_key, &kp.replyKey);
 983         if (ret) {
 984             krb5_clear_error_message(context);
 985             goto out;
 986         }
 987
 988         ret = krb5_crypto_init(context, reply_key, 0, &ascrypto);
 989         if (ret) {
 990             krb5_clear_error_message(context);
 991             goto out;
 992         }
 993
 994         ret = krb5_create_checksum(context, ascrypto, 6, 0,
 995                                    req_buffer->data, req_buffer->length,
 996                                    &kp.asChecksum);
 997         if (ret) {
 998             krb5_clear_error_message(context);
 999             goto out;
1000         }
1001
1002         ret = krb5_crypto_destroy(context, ascrypto);
1003         if (ret) {
1004             krb5_clear_error_message(context);
1005             goto out;
1006         }
1007         ASN1_MALLOC_ENCODE(ReplyKeyPack, buf.data, buf.length, &kp, &size,ret);
1008         free_ReplyKeyPack(&kp);
1009     }
1010     if (ret) {
1011         krb5_set_error_message(context, ret, "ASN.1 encoding of ReplyKeyPack "
1012                                "failed (%d)", ret);
1013         goto out;
1014     }
1015     if (buf.length != size)
1016         krb5_abortx(context, "Internal ASN.1 encoder error");
1017
1018     {
1019         hx509_query *q;
1020         hx509_cert cert;
1021
1022         ret = hx509_query_alloc(context->hx509ctx, &q);
1023         if (ret)
1024             goto out;
1025
1026         hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
1027         if (config->pkinit_kdc_friendly_name)
1028             hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);
1029
1030         ret = hx509_certs_find(context->hx509ctx,
1031                                kdc_identity->certs,
1032                                q,
1033                                &cert);
1034         hx509_query_free(context->hx509ctx, q);
1035         if (ret)
1036             goto out;
1037
1038         ret = hx509_cms_create_signed_1(context->hx509ctx,
1039                                         0,
1040                                         sdAlg,
1041                                         buf.data,
1042                                         buf.length,
1043                                         NULL,
1044                                         cert,
1045                                         cp->peer,
1046                                         cp->client_anchors,
1047                                         kdc_identity->certpool,
1048                                         &signed_data);
1049         *kdc_cert = cert;
1050     }
1051
1052     krb5_data_free(&buf);
1053     if (ret)
1054         goto out;
1055
1056     if (cp->type == PKINIT_WIN2K) {
1057         ret = hx509_cms_wrap_ContentInfo(&asn1_oid_id_pkcs7_signedData,
1058                                          &signed_data,
1059                                          &buf);
1060         if (ret)
1061             goto out;
1062         krb5_data_free(&signed_data);
1063         signed_data = buf;
1064     }
1065
1066     ret = hx509_cms_envelope_1(context->hx509ctx,
1067                                HX509_CMS_EV_NO_KU_CHECK,
1068                                cp->cert,
1069                                signed_data.data, signed_data.length,
1070                                envelopedAlg,
1071                                evAlg, &buf);
1072     if (ret)
1073         goto out;
1074
1075     ret = _krb5_pk_mk_ContentInfo(context,
1076                                   &buf,
1077                                   &asn1_oid_id_pkcs7_envelopedData,
1078                                   content_info);
1079 out:
1080     if (ret && *kdc_cert) {
1081         hx509_cert_free(*kdc_cert);
1082         *kdc_cert = NULL;
1083     }
1084
1085     krb5_data_free(&buf);
1086     krb5_data_free(&signed_data);
1087     return ret;
1088 }
1089
1090 /*
1091  *
1092  */
1093
1094 static krb5_error_code
1095 pk_mk_pa_reply_dh(krb5_context context,
1096                   krb5_kdc_configuration *config,
1097                   pk_client_params *cp,
1098                   ContentInfo *content_info,
1099                   hx509_cert *kdc_cert)
1100 {
1101     KDCDHKeyInfo dh_info;
1102     krb5_data signed_data, buf;
1103     ContentInfo contentinfo;
1104     krb5_error_code ret;
1105     hx509_cert cert;
1106     hx509_query *q;
1107     size_t size = 0;
1108
1109     memset(&contentinfo, 0, sizeof(contentinfo));
1110     memset(&dh_info, 0, sizeof(dh_info));
1111     krb5_data_zero(&signed_data);
1112     krb5_data_zero(&buf);
1113
1114     *kdc_cert = NULL;
1115
1116     if (cp->keyex == USE_DH) {
1117         DH *kdc_dh = cp->u.dh.key;
1118         heim_integer i;
1119
1120         ret = BN_to_integer(context, kdc_dh->pub_key, &i);
1121         if (ret)
1122             return ret;
1123
1124         ASN1_MALLOC_ENCODE(DHPublicKey, buf.data, buf.length, &i, &size, ret);
1125         der_free_heim_integer(&i);
1126         if (ret) {
1127             krb5_set_error_message(context, ret, "ASN.1 encoding of "
1128                                    "DHPublicKey failed (%d)", ret);
1129             return ret;
1130         }
1131         if (buf.length != size)
1132             krb5_abortx(context, "Internal ASN.1 encoder error");
1133
1134         dh_info.subjectPublicKey.length = buf.length * 8;
1135         dh_info.subjectPublicKey.data = buf.data;
1136         krb5_data_zero(&buf);
1137 #ifdef HAVE_OPENSSL
1138     } else if (cp->keyex == USE_ECDH) {
1139         unsigned char *p;
1140         int len;
1141
1142         len = i2o_ECPublicKey(cp->u.ecdh.key, NULL);
1143         if (len <= 0)
1144             abort();
1145
1146         p = malloc(len);
1147         if (p == NULL)
1148             abort();
1149
1150         dh_info.subjectPublicKey.length = len * 8;
1151         dh_info.subjectPublicKey.data = p;
1152
1153         len = i2o_ECPublicKey(cp->u.ecdh.key, &p);
1154         if (len <= 0)
1155             abort();
1156 #endif
1157     } else
1158         krb5_abortx(context, "no keyex selected ?");
1159
1160
1161     dh_info.nonce = cp->nonce;
1162
1163     ASN1_MALLOC_ENCODE(KDCDHKeyInfo, buf.data, buf.length, &dh_info, &size,
1164                        ret);
1165     if (ret) {
1166         krb5_set_error_message(context, ret, "ASN.1 encoding of "
1167                                "KdcDHKeyInfo failed (%d)", ret);
1168         goto out;
1169     }
1170     if (buf.length != size)
1171         krb5_abortx(context, "Internal ASN.1 encoder error");
1172
1173     /*
1174      * Create the SignedData structure and sign the KdcDHKeyInfo
1175      * filled in above
1176      */
1177
1178     ret = hx509_query_alloc(context->hx509ctx, &q);
1179     if (ret)
1180         goto out;
1181
1182     hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
1183     if (config->pkinit_kdc_friendly_name)
1184         hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);
1185
1186     ret = hx509_certs_find(context->hx509ctx,
1187                            kdc_identity->certs,
1188                            q,
1189                            &cert);
1190     hx509_query_free(context->hx509ctx, q);
1191     if (ret)
1192         goto out;
1193
1194     ret = hx509_cms_create_signed_1(context->hx509ctx,
1195                                     0,
1196                                     &asn1_oid_id_pkdhkeydata,
1197                                     buf.data,
1198                                     buf.length,
1199                                     NULL,
1200                                     cert,
1201                                     cp->peer,
1202                                     cp->client_anchors,
1203                                     kdc_identity->certpool,
1204                                     &signed_data);
1205     if (ret) {
1206         kdc_log(context, config, 0, "Failed signing the DH* reply: %d", ret);
1207         goto out;
1208     }
1209     *kdc_cert = cert;
1210
1211     ret = _krb5_pk_mk_ContentInfo(context,
1212                                   &signed_data,
1213                                   &asn1_oid_id_pkcs7_signedData,
1214                                   content_info);
1215     if (ret)
1216         goto out;
1217
1218  out:
1219     if (ret && *kdc_cert) {
1220         hx509_cert_free(*kdc_cert);
1221         *kdc_cert = NULL;
1222     }
1223
1224     krb5_data_free(&buf);
1225     krb5_data_free(&signed_data);
1226     free_KDCDHKeyInfo(&dh_info);
1227
1228     return ret;
1229 }
1230
1231 /*
1232  *
1233  */
1234
1235 krb5_error_code
1236 _kdc_pk_mk_pa_reply(krb5_context context,
1237                     krb5_kdc_configuration *config,
1238                     pk_client_params *cp,
1239                     const hdb_entry_ex *client,
1240                     krb5_enctype sessionetype,
1241                     const KDC_REQ *req,
1242                     const krb5_data *req_buffer,
1243                     krb5_keyblock *reply_key,
1244                     krb5_keyblock *sessionkey,
1245                     METHOD_DATA *md)
1246 {
1247     krb5_error_code ret;
1248     void *buf = NULL;
1249     size_t len = 0, size = 0;
1250     krb5_enctype enctype;
1251     int pa_type;
1252     hx509_cert kdc_cert = NULL;
1253     size_t i;
1254
1255     if (!config->enable_pkinit) {
1256         krb5_clear_error_message(context);
1257         return 0;
1258     }
1259
1260     if (req->req_body.etype.len > 0) {
1261         for (i = 0; i < req->req_body.etype.len; i++)
1262             if (krb5_enctype_valid(context, req->req_body.etype.val[i]) == 0)
1263                 break;
1264         if (req->req_body.etype.len <= i) {
1265             ret = KRB5KRB_ERR_GENERIC;
1266             krb5_set_error_message(context, ret,
1267                                    "No valid enctype available from client");
1268             goto out;
1269         }
1270         enctype = req->req_body.etype.val[i];
1271     } else
1272         enctype = ETYPE_DES3_CBC_SHA1;
1273
1274     if (cp->type == PKINIT_27) {
1275         PA_PK_AS_REP rep;
1276         const char *type, *other = "";
1277
1278         memset(&rep, 0, sizeof(rep));
1279
1280         pa_type = KRB5_PADATA_PK_AS_REP;
1281
1282         if (cp->keyex == USE_RSA) {
1283             ContentInfo info;
1284
1285             type = "enckey";
1286
1287             rep.element = choice_PA_PK_AS_REP_encKeyPack;
1288
1289             ret = krb5_generate_random_keyblock(context, enctype,
1290                                                 &cp->reply_key);
1291             if (ret) {
1292                 free_PA_PK_AS_REP(&rep);
1293                 goto out;
1294             }
1295             ret = pk_mk_pa_reply_enckey(context,
1296                                         config,
1297                                         cp,
1298                                         req,
1299                                         req_buffer,
1300                                         &cp->reply_key,
1301                                         &info,
1302                                         &kdc_cert);
1303             if (ret) {
1304                 free_PA_PK_AS_REP(&rep);
1305                 goto out;
1306             }
1307             ASN1_MALLOC_ENCODE(ContentInfo, rep.u.encKeyPack.data,
1308                                rep.u.encKeyPack.length, &info, &size,
1309                                ret);
1310             free_ContentInfo(&info);
1311             if (ret) {
1312                 krb5_set_error_message(context, ret, "encoding of Key ContentInfo "
1313                                        "failed %d", ret);
1314                 free_PA_PK_AS_REP(&rep);
1315                 goto out;
1316             }
1317             if (rep.u.encKeyPack.length != size)
1318                 krb5_abortx(context, "Internal ASN.1 encoder error");
1319
1320             ret = krb5_generate_random_keyblock(context, sessionetype,
1321                                                 sessionkey);
1322             if (ret) {
1323                 free_PA_PK_AS_REP(&rep);
1324                 goto out;
1325             }
1326
1327         } else {
1328             ContentInfo info;
1329
1330             switch (cp->keyex) {
1331             case USE_DH: type = "dh"; break;
1332 #ifdef HAVE_OPENSSL
1333             case USE_ECDH: type = "ecdh"; break;
1334 #endif
1335             default: krb5_abortx(context, "unknown keyex"); break;
1336             }
1337
1338             if (cp->dh_group_name)
1339                 other = cp->dh_group_name;
1340
1341             rep.element = choice_PA_PK_AS_REP_dhInfo;
1342
1343             ret = generate_dh_keyblock(context, cp, enctype);
1344             if (ret)
1345                 return ret;
1346
1347             ret = pk_mk_pa_reply_dh(context, config,
1348                                     cp,
1349                                     &info,
1350                                     &kdc_cert);
1351             if (ret) {
1352                 free_PA_PK_AS_REP(&rep);
1353                 krb5_set_error_message(context, ret,
1354                                        "create pa-reply-dh "
1355                                        "failed %d", ret);
1356                 goto out;
1357             }
1358
1359             ASN1_MALLOC_ENCODE(ContentInfo, rep.u.dhInfo.dhSignedData.data,
1360                                rep.u.dhInfo.dhSignedData.length, &info, &size,
1361                                ret);
1362             free_ContentInfo(&info);
1363             if (ret) {
1364                 krb5_set_error_message(context, ret,
1365                                        "encoding of Key ContentInfo "
1366                                        "failed %d", ret);
1367                 free_PA_PK_AS_REP(&rep);
1368                 goto out;
1369             }
1370             if (rep.u.encKeyPack.length != size)
1371                 krb5_abortx(context, "Internal ASN.1 encoder error");
1372
1373             /* XXX KRB-FX-CF2 */
1374             ret = krb5_generate_random_keyblock(context, sessionetype,
1375                                                 sessionkey);
1376             if (ret) {
1377                 free_PA_PK_AS_REP(&rep);
1378                 goto out;
1379             }
1380
1381             /* XXX Add PA-PKINIT-KX */
1382
1383         }
1384
1385 #define use_btmm_with_enckey 0
1386         if (use_btmm_with_enckey && rep.element == choice_PA_PK_AS_REP_encKeyPack) {
1387             PA_PK_AS_REP_BTMM btmm;
1388             heim_any any;
1389
1390             any.data = rep.u.encKeyPack.data;
1391             any.length = rep.u.encKeyPack.length;
1392
1393             btmm.dhSignedData = NULL;
1394             btmm.encKeyPack = &any;
1395
1396             ASN1_MALLOC_ENCODE(PA_PK_AS_REP_BTMM, buf, len, &btmm, &size, ret);
1397         } else {
1398             ASN1_MALLOC_ENCODE(PA_PK_AS_REP, buf, len, &rep, &size, ret);
1399         }
1400
1401         free_PA_PK_AS_REP(&rep);
1402         if (ret) {
1403             krb5_set_error_message(context, ret,
1404                                    "encode PA-PK-AS-REP failed %d", ret);
1405             goto out;
1406         }
1407         if (len != size)
1408             krb5_abortx(context, "Internal ASN.1 encoder error");
1409
1410         kdc_log(context, config, 0, "PK-INIT using %s %s", type, other);
1411
1412     } else if (cp->type == PKINIT_WIN2K) {
1413         PA_PK_AS_REP_Win2k rep;
1414         ContentInfo info;
1415
1416         if (cp->keyex != USE_RSA) {
1417             ret = KRB5KRB_ERR_GENERIC;
1418             krb5_set_error_message(context, ret,
1419                                    "Windows PK-INIT doesn't support DH");
1420             goto out;
1421         }
1422
1423         memset(&rep, 0, sizeof(rep));
1424
1425         pa_type = KRB5_PADATA_PK_AS_REP_19;
1426         rep.element = choice_PA_PK_AS_REP_Win2k_encKeyPack;
1427
1428         ret = krb5_generate_random_keyblock(context, enctype,
1429                                             &cp->reply_key);
1430         if (ret) {
1431             free_PA_PK_AS_REP_Win2k(&rep);
1432             goto out;
1433         }
1434         ret = pk_mk_pa_reply_enckey(context,
1435                                     config,
1436                                     cp,
1437                                     req,
1438                                     req_buffer,
1439                                     &cp->reply_key,
1440                                     &info,
1441                                     &kdc_cert);
1442         if (ret) {
1443             free_PA_PK_AS_REP_Win2k(&rep);
1444             goto out;
1445         }
1446         ASN1_MALLOC_ENCODE(ContentInfo, rep.u.encKeyPack.data,
1447                            rep.u.encKeyPack.length, &info, &size,
1448                            ret);
1449         free_ContentInfo(&info);
1450         if (ret) {
1451             krb5_set_error_message(context, ret, "encoding of Key ContentInfo "
1452                                   "failed %d", ret);
1453             free_PA_PK_AS_REP_Win2k(&rep);
1454             goto out;
1455         }
1456         if (rep.u.encKeyPack.length != size)
1457             krb5_abortx(context, "Internal ASN.1 encoder error");
1458
1459         ASN1_MALLOC_ENCODE(PA_PK_AS_REP_Win2k, buf, len, &rep, &size, ret);
1460         free_PA_PK_AS_REP_Win2k(&rep);
1461         if (ret) {
1462             krb5_set_error_message(context, ret,
1463                                   "encode PA-PK-AS-REP-Win2k failed %d", ret);
1464             goto out;
1465         }
1466         if (len != size)
1467             krb5_abortx(context, "Internal ASN.1 encoder error");
1468
1469         ret = krb5_generate_random_keyblock(context, sessionetype,
1470                                             sessionkey);
1471         if (ret) {
1472             free(buf);
1473             goto out;
1474         }
1475
1476     } else
1477         krb5_abortx(context, "PK-INIT internal error");
1478
1479
1480     ret = krb5_padata_add(context, md, pa_type, buf, len);
1481     if (ret) {
1482         krb5_set_error_message(context, ret,
1483                                "Failed adding PA-PK-AS-REP %d", ret);
1484         free(buf);
1485         goto out;
1486     }
1487
1488     if (config->pkinit_kdc_ocsp_file) {
1489
1490         if (ocsp.expire == 0 && ocsp.next_update > kdc_time) {
1491             struct stat sb;
1492             int fd;
1493
1494             krb5_data_free(&ocsp.data);
1495
1496             ocsp.expire = 0;
1497             ocsp.next_update = kdc_time + 60 * 5;
1498
1499             fd = open(config->pkinit_kdc_ocsp_file, O_RDONLY);
1500             if (fd < 0) {
1501                 kdc_log(context, config, 0,
1502                         "PK-INIT failed to open ocsp data file %d", errno);
1503                 goto out_ocsp;
1504             }
1505             ret = fstat(fd, &sb);
1506             if (ret) {
1507                 ret = errno;
1508                 close(fd);
1509                 kdc_log(context, config, 0,
1510                         "PK-INIT failed to stat ocsp data %d", ret);
1511                 goto out_ocsp;
1512             }
1513
1514             ret = krb5_data_alloc(&ocsp.data, sb.st_size);
1515             if (ret) {
1516                 close(fd);
1517                 kdc_log(context, config, 0,
1518                         "PK-INIT failed to stat ocsp data %d", ret);
1519                 goto out_ocsp;
1520             }
1521             ocsp.data.length = sb.st_size;
1522             ret = read(fd, ocsp.data.data, sb.st_size);
1523             close(fd);
1524             if (ret != sb.st_size) {
1525                 kdc_log(context, config, 0,
1526                         "PK-INIT failed to read ocsp data %d", errno);
1527                 goto out_ocsp;
1528             }
1529
1530             ret = hx509_ocsp_verify(context->hx509ctx,
1531                                     kdc_time,
1532                                     kdc_cert,
1533                                     0,
1534                                     ocsp.data.data, ocsp.data.length,
1535                                     &ocsp.expire);
1536             if (ret) {
1537                 kdc_log(context, config, 0,
1538                         "PK-INIT failed to verify ocsp data %d", ret);
1539                 krb5_data_free(&ocsp.data);
1540                 ocsp.expire = 0;
1541             } else if (ocsp.expire > 180) {
1542                 ocsp.expire -= 180; /* refetch the ocsp before it expire */
1543                 ocsp.next_update = ocsp.expire;
1544             } else {
1545                 ocsp.next_update = kdc_time;
1546             }
1547         out_ocsp:
1548             ret = 0;
1549         }
1550
1551         if (ocsp.expire != 0 && ocsp.expire > kdc_time) {
1552
1553             ret = krb5_padata_add(context, md,
1554                                   KRB5_PADATA_PA_PK_OCSP_RESPONSE,
1555                                   ocsp.data.data, ocsp.data.length);
1556             if (ret) {
1557                 krb5_set_error_message(context, ret,
1558                                        "Failed adding OCSP response %d", ret);
1559                 goto out;
1560             }
1561         }
1562     }
1563
1564 out:
1565     if (kdc_cert)
1566         hx509_cert_free(kdc_cert);
1567
1568     if (ret == 0)
1569         ret = krb5_copy_keyblock_contents(context, &cp->reply_key, reply_key);
1570     return ret;
1571 }
1572
1573 static int
1574 match_rfc_san(krb5_context context,
1575               krb5_kdc_configuration *config,
1576               hx509_context hx509ctx,
1577               hx509_cert client_cert,
1578               krb5_const_principal match)
1579 {
1580     hx509_octet_string_list list;
1581     int ret, found = 0;
1582     size_t i;
1583
1584     memset(&list, 0 , sizeof(list));
1585
1586     ret = hx509_cert_find_subjectAltName_otherName(hx509ctx,
1587                                                    client_cert,
1588                                                    &asn1_oid_id_pkinit_san,
1589                                                    &list);
1590     if (ret)
1591         goto out;
1592
1593     for (i = 0; !found && i < list.len; i++) {
1594         krb5_principal_data principal;
1595         KRB5PrincipalName kn;
1596         size_t size;
1597
1598         ret = decode_KRB5PrincipalName(list.val[i].data,
1599                                        list.val[i].length,
1600                                        &kn, &size);
1601         if (ret) {
1602             const char *msg = krb5_get_error_message(context, ret);
1603             kdc_log(context, config, 0,
1604                     "Decoding kerberos name in certificate failed: %s", msg);
1605             krb5_free_error_message(context, msg);
1606             break;
1607         }
1608         if (size != list.val[i].length) {
1609             kdc_log(context, config, 0,
1610                     "Decoding kerberos name have extra bits on the end");
1611             return KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1612         }
1613
1614         memset(&principal, 0, sizeof (principal));
1615         principal.name = kn.principalName;
1616         principal.realm = kn.realm;
1617
1618         if (krb5_principal_compare(context, &principal, match) == TRUE)
1619             found = 1;
1620         free_KRB5PrincipalName(&kn);
1621     }
1622
1623 out:
1624     hx509_free_octet_string_list(&list);
1625     if (ret)
1626         return ret;
1627
1628     if (!found)
1629         return KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1630
1631     return 0;
1632 }
1633
1634 static int
1635 match_ms_upn_san(krb5_context context,
1636                  krb5_kdc_configuration *config,
1637                  hx509_context hx509ctx,
1638                  hx509_cert client_cert,
1639                  HDB *clientdb,
1640                  hdb_entry_ex *client)
1641 {
1642     hx509_octet_string_list list;
1643     krb5_principal principal = NULL;
1644     int ret;
1645     MS_UPN_SAN upn;
1646     size_t size;
1647
1648     memset(&list, 0 , sizeof(list));
1649
1650     ret = hx509_cert_find_subjectAltName_otherName(hx509ctx,
1651                                                    client_cert,
1652                                                    &asn1_oid_id_pkinit_ms_san,
1653                                                    &list);
1654     if (ret)
1655         goto out;
1656
1657     if (list.len != 1) {
1658         kdc_log(context, config, 0,
1659                 "More then one PK-INIT MS UPN SAN");
1660         ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1661         goto out;
1662     }
1663
1664     ret = decode_MS_UPN_SAN(list.val[0].data, list.val[0].length, &upn, &size);
1665     if (ret) {
1666         kdc_log(context, config, 0, "Decode of MS-UPN-SAN failed");
1667         goto out;
1668     }
1669     if (size != list.val[0].length) {
1670         free_MS_UPN_SAN(&upn);
1671         kdc_log(context, config, 0, "Trailing data in ");
1672         ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1673         goto out;
1674     }
1675
1676     kdc_log(context, config, 0, "found MS UPN SAN: %s", upn);
1677
1678     ret = krb5_parse_name(context, upn, &principal);
1679     free_MS_UPN_SAN(&upn);
1680     if (ret) {
1681         kdc_log(context, config, 0, "Failed to parse principal in MS UPN SAN");
1682         goto out;
1683     }
1684
1685     if (clientdb->hdb_check_pkinit_ms_upn_match) {
1686         ret = clientdb->hdb_check_pkinit_ms_upn_match(context, clientdb, client, principal);
1687     } else {
1688
1689         /*
1690          * This is very wrong, but will do for a fallback
1691          */
1692         strupr(principal->realm);
1693
1694         if (krb5_principal_compare(context, principal, client->entry.principal) == FALSE)
1695             ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1696     }
1697
1698 out:
1699     if (principal)
1700         krb5_free_principal(context, principal);
1701     hx509_free_octet_string_list(&list);
1702
1703     return ret;
1704 }
1705
1706 krb5_error_code
1707 _kdc_pk_check_client(krb5_context context,
1708                      krb5_kdc_configuration *config,
1709                      HDB *clientdb,
1710                      hdb_entry_ex *client,
1711                      pk_client_params *cp,
1712                      char **subject_name)
1713 {
1714     const HDB_Ext_PKINIT_acl *acl;
1715     const HDB_Ext_PKINIT_cert *pc;
1716     krb5_error_code ret;
1717     hx509_name name;
1718     size_t i;
1719
1720     if (cp->cert == NULL) {
1721
1722         *subject_name = strdup("anonymous client client");
1723         if (*subject_name == NULL)
1724             return ENOMEM;
1725         return 0;
1726     }
1727
1728     ret = hx509_cert_get_base_subject(context->hx509ctx,
1729                                       cp->cert,
1730                                       &name);
1731     if (ret)
1732         return ret;
1733
1734     ret = hx509_name_to_string(name, subject_name);
1735     hx509_name_free(&name);
1736     if (ret)
1737         return ret;
1738
1739     kdc_log(context, config, 0,
1740             "Trying to authorize PK-INIT subject DN %s",
1741             *subject_name);
1742
1743     ret = hdb_entry_get_pkinit_cert(&client->entry, &pc);
1744     if (ret == 0 && pc) {
1745         hx509_cert cert;
1746         size_t j;
1747
1748         for (j = 0; j < pc->len; j++) {
1749             cert = hx509_cert_init_data(context->hx509ctx,
1750                                         pc->val[j].cert.data,
1751                                         pc->val[j].cert.length,
1752                                         NULL);
1753             if (cert == NULL)
1754                 continue;
1755             ret = hx509_cert_cmp(cert, cp->cert);
1756             hx509_cert_free(cert);
1757             if (ret == 0) {
1758                 kdc_log(context, config, 5,
1759                         "Found matching PK-INIT cert in hdb");
1760                 return 0;
1761             }
1762         }
1763     }
1764
1765
1766     if (config->pkinit_princ_in_cert) {
1767         ret = match_rfc_san(context, config,
1768                             context->hx509ctx,
1769                             cp->cert,
1770                             client->entry.principal);
1771         if (ret == 0) {
1772             kdc_log(context, config, 5,
1773                     "Found matching PK-INIT SAN in certificate");
1774             return 0;
1775         }
1776         ret = match_ms_upn_san(context, config,
1777                                context->hx509ctx,
1778                                cp->cert,
1779                                clientdb,
1780                                client);
1781         if (ret == 0) {
1782             kdc_log(context, config, 5,
1783                     "Found matching MS UPN SAN in certificate");
1784             return 0;
1785         }
1786     }
1787
1788     ret = hdb_entry_get_pkinit_acl(&client->entry, &acl);
1789     if (ret == 0 && acl != NULL) {
1790         /*
1791          * Cheat here and compare the generated name with the string
1792          * and not the reverse.
1793          */
1794         for (i = 0; i < acl->len; i++) {
1795             if (strcmp(*subject_name, acl->val[0].subject) != 0)
1796                 continue;
1797
1798             /* Don't support isser and anchor checking right now */
1799             if (acl->val[0].issuer)
1800                 continue;
1801             if (acl->val[0].anchor)
1802                 continue;
1803
1804             kdc_log(context, config, 5,
1805                     "Found matching PK-INIT database ACL");
1806             return 0;
1807         }
1808     }
1809
1810     for (i = 0; i < principal_mappings.len; i++) {
1811         krb5_boolean b;
1812
1813         b = krb5_principal_compare(context,
1814                                    client->entry.principal,
1815                                    principal_mappings.val[i].principal);
1816         if (b == FALSE)
1817             continue;
1818         if (strcmp(principal_mappings.val[i].subject, *subject_name) != 0)
1819             continue;
1820         kdc_log(context, config, 5,
1821                 "Found matching PK-INIT FILE ACL");
1822         return 0;
1823     }
1824
1825     ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
1826     krb5_set_error_message(context, ret,
1827                           "PKINIT no matching principals for %s",
1828                           *subject_name);
1829
1830     kdc_log(context, config, 5,
1831             "PKINIT no matching principals for %s",
1832             *subject_name);
1833
1834     free(*subject_name);
1835     *subject_name = NULL;
1836
1837     return ret;
1838 }
1839
1840 static krb5_error_code
1841 add_principal_mapping(krb5_context context,
1842                       const char *principal_name,
1843                       const char * subject)
1844 {
1845    struct pk_allowed_princ *tmp;
1846    krb5_principal principal;
1847    krb5_error_code ret;
1848
1849    tmp = realloc(principal_mappings.val,
1850                  (principal_mappings.len + 1) * sizeof(*tmp));
1851    if (tmp == NULL)
1852        return ENOMEM;
1853    principal_mappings.val = tmp;
1854
1855    ret = krb5_parse_name(context, principal_name, &principal);
1856    if (ret)
1857        return ret;
1858
1859    principal_mappings.val[principal_mappings.len].principal = principal;
1860
1861    principal_mappings.val[principal_mappings.len].subject = strdup(subject);
1862    if (principal_mappings.val[principal_mappings.len].subject == NULL) {
1863        krb5_free_principal(context, principal);
1864        return ENOMEM;
1865    }
1866    principal_mappings.len++;
1867
1868    return 0;
1869 }
1870
1871 krb5_error_code
1872 _kdc_add_inital_verified_cas(krb5_context context,
1873                              krb5_kdc_configuration *config,
1874                              pk_client_params *cp,
1875                              EncTicketPart *tkt)
1876 {
1877     AD_INITIAL_VERIFIED_CAS cas;
1878     krb5_error_code ret;
1879     krb5_data data;
1880     size_t size = 0;
1881
1882     memset(&cas, 0, sizeof(cas));
1883
1884     /* XXX add CAs to cas here */
1885
1886     ASN1_MALLOC_ENCODE(AD_INITIAL_VERIFIED_CAS, data.data, data.length,
1887                        &cas, &size, ret);
1888     if (ret)
1889         return ret;
1890     if (data.length != size)
1891         krb5_abortx(context, "internal asn.1 encoder error");
1892
1893     ret = _kdc_tkt_add_if_relevant_ad(context, tkt,
1894                                       KRB5_AUTHDATA_INITIAL_VERIFIED_CAS,
1895                                       &data);
1896     krb5_data_free(&data);
1897     return ret;
1898 }
1899
1900 /*
1901  *
1902  */
1903
1904 static void
1905 load_mappings(krb5_context context, const char *fn)
1906 {
1907     krb5_error_code ret;
1908     char buf[1024];
1909     unsigned long lineno = 0;
1910     FILE *f;
1911
1912     f = fopen(fn, "r");
1913     if (f == NULL)
1914         return;
1915
1916     while (fgets(buf, sizeof(buf), f) != NULL) {
1917         char *subject_name, *p;
1918
1919         buf[strcspn(buf, "\n")] = '\0';
1920         lineno++;
1921
1922         p = buf + strspn(buf, " \t");
1923
1924         if (*p == '#' || *p == '\0')
1925             continue;
1926
1927         subject_name = strchr(p, ':');
1928         if (subject_name == NULL) {
1929             krb5_warnx(context, "pkinit mapping file line %lu "
1930                        "missing \":\" :%s",
1931                        lineno, buf);
1932             continue;
1933         }
1934         *subject_name++ = '\0';
1935
1936         ret = add_principal_mapping(context, p, subject_name);
1937         if (ret) {
1938             krb5_warn(context, ret, "failed to add line %lu \":\" :%s\n",
1939                       lineno, buf);
1940             continue;
1941         }
1942     }
1943
1944     fclose(f);
1945 }
1946
1947 /*
1948  *
1949  */
1950
1951 krb5_error_code
1952 krb5_kdc_pk_initialize(krb5_context context,
1953                        krb5_kdc_configuration *config,
1954                        const char *user_id,
1955                        const char *anchors,
1956                        char **pool,
1957                        char **revoke_list)
1958 {
1959     const char *file;
1960     char *fn = NULL;
1961     krb5_error_code ret;
1962
1963     file = krb5_config_get_string(context, NULL,
1964                                   "libdefaults", "moduli", NULL);
1965
1966     ret = _krb5_parse_moduli(context, file, &moduli);
1967     if (ret)
1968         krb5_err(context, 1, ret, "PKINIT: failed to load modidi file");
1969
1970     principal_mappings.len = 0;
1971     principal_mappings.val = NULL;
1972
1973     ret = _krb5_pk_load_id(context,
1974                            &kdc_identity,
1975                            user_id,
1976                            anchors,
1977                            pool,
1978                            revoke_list,
1979                            NULL,
1980                            NULL,
1981                            NULL);
1982     if (ret) {
1983         krb5_warn(context, ret, "PKINIT: ");
1984         config->enable_pkinit = 0;
1985         return ret;
1986     }
1987
1988     {
1989         hx509_query *q;
1990         hx509_cert cert;
1991
1992         ret = hx509_query_alloc(context->hx509ctx, &q);
1993         if (ret) {
1994             krb5_warnx(context, "PKINIT: out of memory");
1995             return ENOMEM;
1996         }
1997
1998         hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
1999         if (config->pkinit_kdc_friendly_name)
2000             hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);
2001
2002         ret = hx509_certs_find(context->hx509ctx,
2003                                kdc_identity->certs,
2004                                q,
2005                                &cert);
2006         hx509_query_free(context->hx509ctx, q);
2007         if (ret == 0) {
2008             if (hx509_cert_check_eku(context->hx509ctx, cert,
2009                                      &asn1_oid_id_pkkdcekuoid, 0)) {
2010                 hx509_name name;
2011                 char *str;
2012                 ret = hx509_cert_get_subject(cert, &name);
2013                 if (ret == 0) {
2014                     hx509_name_to_string(name, &str);
2015                     krb5_warnx(context, "WARNING Found KDC certificate (%s)"
2016                                "is missing the PK-INIT KDC EKU, this is bad for "
2017                                "interoperability.", str);
2018                     hx509_name_free(&name);
2019                     free(str);
2020                 }
2021             }
2022             hx509_cert_free(cert);
2023         } else
2024             krb5_warnx(context, "PKINIT: failed to find a signing "
2025                        "certifiate with a public key");
2026     }
2027
2028     if (krb5_config_get_bool_default(context,
2029                                      NULL,
2030                                      FALSE,
2031                                      "kdc",
2032                                      "pkinit_allow_proxy_certificate",
2033                                      NULL))
2034         config->pkinit_allow_proxy_certs = 1;
2035
2036     file = krb5_config_get_string(context,
2037                                   NULL,
2038                                   "kdc",
2039                                   "pkinit_mappings_file",
2040                                   NULL);
2041     if (file == NULL) {
2042         int aret;
2043
2044         aret = asprintf(&fn, "%s/pki-mapping", hdb_db_dir(context));
2045         if (aret == -1) {
2046             krb5_warnx(context, "PKINIT: out of memory");
2047             return ENOMEM;
2048         }
2049
2050         file = fn;
2051     }
2052
2053     load_mappings(context, file);
2054     if (fn)
2055         free(fn);
2056
2057     return 0;
2058 }
2059
2060 #endif /* PKINIT */