kdc/kerberos5.c

   1 /*
   2  * Copyright (c) 1997-2007 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "kdc_locl.h"
  35
  36 RCSID("$Id$");
  37
  38 #define MAX_TIME ((time_t)((1U << 31) - 1))
  39
  40 void
  41 _kdc_fix_time(time_t **t)
  42 {
  43     if(*t == NULL){
  44         ALLOC(*t);
  45         **t = MAX_TIME;
  46     }
  47     if(**t == 0) **t = MAX_TIME; /* fix for old clients */
  48 }
  49
  50 static int
  51 realloc_method_data(METHOD_DATA *md)
  52 {
  53     PA_DATA *pa;
  54     pa = realloc(md->val, (md->len + 1) * sizeof(*md->val));
  55     if(pa == NULL)
  56         return ENOMEM;
  57     md->val = pa;
  58     md->len++;
  59     return 0;
  60 }
  61
  62 static void
  63 set_salt_padata (METHOD_DATA *md, Salt *salt)
  64 {
  65     if (salt) {
  66         realloc_method_data(md);
  67         md->val[md->len - 1].padata_type = salt->type;
  68         der_copy_octet_string(&salt->salt,
  69                               &md->val[md->len - 1].padata_value);
  70     }
  71 }
  72
  73 const PA_DATA*
  74 _kdc_find_padata(const KDC_REQ *req, int *start, int type)
  75 {
  76     if (req->padata == NULL)
  77         return NULL;
  78
  79     while(*start < req->padata->len){
  80         (*start)++;
  81         if(req->padata->val[*start - 1].padata_type == type)
  82             return &req->padata->val[*start - 1];
  83     }
  84     return NULL;
  85 }
  86
  87 /*
  88  * This is a hack to allow predefined weak services, like afs to
  89  * still use weak types
  90  */
  91
  92 krb5_boolean
  93 _kdc_is_weak_exception(krb5_principal principal, krb5_enctype etype)
  94 {
  95     if (principal->name.name_string.len > 0 &&
  96         strcmp(principal->name.name_string.val[0], "afs") == 0 &&
  97         (etype == ETYPE_DES_CBC_CRC
  98          || etype == ETYPE_DES_CBC_MD4
  99          || etype == ETYPE_DES_CBC_MD5))
 100         return TRUE;
 101     return FALSE;
 102 }
 103
 104
 105 /*
 106  * Detect if `key' is the using the the precomputed `default_salt'.
 107  */
 108
 109 static krb5_boolean
 110 is_default_salt_p(const krb5_salt *default_salt, const Key *key)
 111 {
 112     if (key->salt == NULL)
 113         return TRUE;
 114     if (default_salt->salttype != key->salt->type)
 115         return FALSE;
 116     if (krb5_data_cmp(&default_salt->saltvalue, &key->salt->salt))
 117         return FALSE;
 118     return TRUE;
 119 }
 120
 121 /*
 122  * return the first appropriate key of `princ' in `ret_key'.  Look for
 123  * all the etypes in (`etypes', `len'), stopping as soon as we find
 124  * one, but preferring one that has default salt
 125  */
 126
 127 krb5_error_code
 128 _kdc_find_etype(krb5_context context, const hdb_entry_ex *princ,
 129                 krb5_enctype *etypes, unsigned len,
 130                 Key **ret_key, krb5_enctype *ret_etype)
 131 {
 132     int i;
 133     krb5_error_code ret = KRB5KDC_ERR_ETYPE_NOSUPP;
 134     krb5_salt def_salt;
 135
 136     krb5_get_pw_salt (context, princ->entry.principal, &def_salt);
 137
 138     for(i = 0; ret != 0 && i < len ; i++) {
 139         Key *key = NULL;
 140
 141         if (krb5_enctype_valid(context, etypes[i]) != 0 &&
 142             !_kdc_is_weak_exception(princ->entry.principal, etypes[i]))
 143             continue;
 144
 145         while (hdb_next_enctype2key(context, &princ->entry, etypes[i], &key) == 0) {
 146             if (key->key.keyvalue.length == 0) {
 147                 ret = KRB5KDC_ERR_NULL_KEY;
 148                 continue;
 149             }
 150             *ret_key   = key;
 151             *ret_etype = etypes[i];
 152             ret = 0;
 153             if (is_default_salt_p(&def_salt, key)) {
 154                 krb5_free_salt (context, def_salt);
 155                 return ret;
 156             }
 157         }
 158     }
 159     krb5_free_salt (context, def_salt);
 160     return ret;
 161 }
 162
 163 krb5_error_code
 164 _kdc_make_anonymous_principalname (PrincipalName *pn)
 165 {
 166     pn->name_type = KRB5_NT_PRINCIPAL;
 167     pn->name_string.len = 1;
 168     pn->name_string.val = malloc(sizeof(*pn->name_string.val));
 169     if (pn->name_string.val == NULL)
 170         return ENOMEM;
 171     pn->name_string.val[0] = strdup("anonymous");
 172     if (pn->name_string.val[0] == NULL) {
 173         free(pn->name_string.val);
 174         pn->name_string.val = NULL;
 175         return ENOMEM;
 176     }
 177     return 0;
 178 }
 179
 180 void
 181 _kdc_log_timestamp(krb5_context context,
 182                    krb5_kdc_configuration *config,
 183                    const char *type,
 184                    KerberosTime authtime, KerberosTime *starttime,
 185                    KerberosTime endtime, KerberosTime *renew_till)
 186 {
 187     char authtime_str[100], starttime_str[100],
 188         endtime_str[100], renewtime_str[100];
 189
 190     krb5_format_time(context, authtime,
 191                      authtime_str, sizeof(authtime_str), TRUE);
 192     if (starttime)
 193         krb5_format_time(context, *starttime,
 194                          starttime_str, sizeof(starttime_str), TRUE);
 195     else
 196         strlcpy(starttime_str, "unset", sizeof(starttime_str));
 197     krb5_format_time(context, endtime,
 198                      endtime_str, sizeof(endtime_str), TRUE);
 199     if (renew_till)
 200         krb5_format_time(context, *renew_till,
 201                          renewtime_str, sizeof(renewtime_str), TRUE);
 202     else
 203         strlcpy(renewtime_str, "unset", sizeof(renewtime_str));
 204
 205     kdc_log(context, config, 5,
 206             "%s authtime: %s starttime: %s endtime: %s renew till: %s",
 207             type, authtime_str, starttime_str, endtime_str, renewtime_str);
 208 }
 209
 210 static void
 211 log_patypes(krb5_context context,
 212             krb5_kdc_configuration *config,
 213             METHOD_DATA *padata)
 214 {
 215     struct rk_strpool *p = NULL;
 216     char *str;
 217     int i;
 218
 219     for (i = 0; i < padata->len; i++) {
 220         switch(padata->val[i].padata_type) {
 221         case KRB5_PADATA_PK_AS_REQ:
 222             p = rk_strpoolprintf(p, "PK-INIT(ietf)");
 223             break;
 224         case KRB5_PADATA_PK_AS_REQ_WIN:
 225             p = rk_strpoolprintf(p, "PK-INIT(win2k)");
 226             break;
 227         case KRB5_PADATA_PA_PK_OCSP_RESPONSE:
 228             p = rk_strpoolprintf(p, "OCSP");
 229             break;
 230         case KRB5_PADATA_ENC_TIMESTAMP:
 231             p = rk_strpoolprintf(p, "encrypted-timestamp");
 232             break;
 233         default:
 234             p = rk_strpoolprintf(p, "%d", padata->val[i].padata_type);
 235             break;
 236         }
 237         if (p && i + 1 < padata->len)
 238             p = rk_strpoolprintf(p, ", ");
 239         if (p == NULL) {
 240             kdc_log(context, config, 0, "out of memory");
 241             return;
 242         }
 243     }
 244     if (p == NULL)
 245         p = rk_strpoolprintf(p, "none");
 246
 247     str = rk_strpoolcollect(p);
 248     kdc_log(context, config, 0, "Client sent patypes: %s", str);
 249     free(str);
 250 }
 251
 252 /*
 253  *
 254  */
 255
 256
 257 krb5_error_code
 258 _kdc_encode_reply(krb5_context context,
 259                   krb5_kdc_configuration *config,
 260                   KDC_REP *rep, const EncTicketPart *et, EncKDCRepPart *ek,
 261                   krb5_enctype etype,
 262                   int skvno, const EncryptionKey *skey,
 263                   int ckvno, const EncryptionKey *reply_key,
 264                   const char **e_text,
 265                   krb5_data *reply)
 266 {
 267     unsigned char *buf;
 268     size_t buf_size;
 269     size_t len;
 270     krb5_error_code ret;
 271     krb5_crypto crypto;
 272
 273     ASN1_MALLOC_ENCODE(EncTicketPart, buf, buf_size, et, &len, ret);
 274     if(ret) {
 275         kdc_log(context, config, 0, "Failed to encode ticket: %s",
 276                 krb5_get_err_text(context, ret));
 277         return ret;
 278     }
 279     if(buf_size != len) {
 280         free(buf);
 281         kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
 282         *e_text = "KDC internal error";
 283         return KRB5KRB_ERR_GENERIC;
 284     }
 285
 286     ret = krb5_crypto_init(context, skey, etype, &crypto);
 287     if (ret) {
 288         free(buf);
 289         kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
 290                 krb5_get_err_text(context, ret));
 291         return ret;
 292     }
 293
 294     ret = krb5_encrypt_EncryptedData(context,
 295                                      crypto,
 296                                      KRB5_KU_TICKET,
 297                                      buf,
 298                                      len,
 299                                      skvno,
 300                                      &rep->ticket.enc_part);
 301     free(buf);
 302     krb5_crypto_destroy(context, crypto);
 303     if(ret) {
 304         kdc_log(context, config, 0, "Failed to encrypt data: %s",
 305                 krb5_get_err_text(context, ret));
 306         return ret;
 307     }
 308
 309     if(rep->msg_type == krb_as_rep && !config->encode_as_rep_as_tgs_rep)
 310         ASN1_MALLOC_ENCODE(EncASRepPart, buf, buf_size, ek, &len, ret);
 311     else
 312         ASN1_MALLOC_ENCODE(EncTGSRepPart, buf, buf_size, ek, &len, ret);
 313     if(ret) {
 314         kdc_log(context, config, 0, "Failed to encode KDC-REP: %s",
 315                 krb5_get_err_text(context, ret));
 316         return ret;
 317     }
 318     if(buf_size != len) {
 319         free(buf);
 320         kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
 321         *e_text = "KDC internal error";
 322         return KRB5KRB_ERR_GENERIC;
 323     }
 324     ret = krb5_crypto_init(context, reply_key, 0, &crypto);
 325     if (ret) {
 326         free(buf);
 327         kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
 328                 krb5_get_err_text(context, ret));
 329         return ret;
 330     }
 331     if(rep->msg_type == krb_as_rep) {
 332         krb5_encrypt_EncryptedData(context,
 333                                    crypto,
 334                                    KRB5_KU_AS_REP_ENC_PART,
 335                                    buf,
 336                                    len,
 337                                    ckvno,
 338                                    &rep->enc_part);
 339         free(buf);
 340         ASN1_MALLOC_ENCODE(AS_REP, buf, buf_size, rep, &len, ret);
 341     } else {
 342         krb5_encrypt_EncryptedData(context,
 343                                    crypto,
 344                                    KRB5_KU_TGS_REP_ENC_PART_SESSION,
 345                                    buf,
 346                                    len,
 347                                    ckvno,
 348                                    &rep->enc_part);
 349         free(buf);
 350         ASN1_MALLOC_ENCODE(TGS_REP, buf, buf_size, rep, &len, ret);
 351     }
 352     krb5_crypto_destroy(context, crypto);
 353     if(ret) {
 354         kdc_log(context, config, 0, "Failed to encode KDC-REP: %s",
 355                 krb5_get_err_text(context, ret));
 356         return ret;
 357     }
 358     if(buf_size != len) {
 359         free(buf);
 360         kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
 361         *e_text = "KDC internal error";
 362         return KRB5KRB_ERR_GENERIC;
 363     }
 364     reply->data = buf;
 365     reply->length = buf_size;
 366     return 0;
 367 }
 368
 369 /*
 370  * Return 1 if the client have only older enctypes, this is for
 371  * determining if the server should send ETYPE_INFO2 or not.
 372  */
 373
 374 static int
 375 older_enctype(krb5_enctype enctype)
 376 {
 377     switch (enctype) {
 378     case ETYPE_DES_CBC_CRC:
 379     case ETYPE_DES_CBC_MD4:
 380     case ETYPE_DES_CBC_MD5:
 381     case ETYPE_DES3_CBC_SHA1:
 382     case ETYPE_ARCFOUR_HMAC_MD5:
 383     case ETYPE_ARCFOUR_HMAC_MD5_56:
 384     /*
 385      * The following three is "old" windows enctypes and is needed for
 386      * windows 2000 hosts.
 387      */
 388     case ETYPE_ARCFOUR_MD4:
 389     case ETYPE_ARCFOUR_HMAC_OLD:
 390     case ETYPE_ARCFOUR_HMAC_OLD_EXP:
 391         return 1;
 392     default:
 393         return 0;
 394     }
 395 }
 396
 397 /*
 398  *
 399  */
 400
 401 static krb5_error_code
 402 make_etype_info_entry(krb5_context context, ETYPE_INFO_ENTRY *ent, Key *key)
 403 {
 404     ent->etype = key->key.keytype;
 405     if(key->salt){
 406 #if 0
 407         ALLOC(ent->salttype);
 408
 409         if(key->salt->type == hdb_pw_salt)
 410             *ent->salttype = 0; /* or 1? or NULL? */
 411         else if(key->salt->type == hdb_afs3_salt)
 412             *ent->salttype = 2;
 413         else {
 414             kdc_log(context, config, 0, "unknown salt-type: %d",
 415                     key->salt->type);
 416             return KRB5KRB_ERR_GENERIC;
 417         }
 418         /* according to `the specs', we can't send a salt if
 419            we have AFS3 salted key, but that requires that you
 420            *know* what cell you are using (e.g by assuming
 421            that the cell is the same as the realm in lower
 422            case) */
 423 #elif 0
 424         ALLOC(ent->salttype);
 425         *ent->salttype = key->salt->type;
 426 #else
 427         /*
 428          * We shouldn't sent salttype since it is incompatible with the
 429          * specification and it breaks windows clients.  The afs
 430          * salting problem is solved by using KRB5-PADATA-AFS3-SALT
 431          * implemented in Heimdal 0.7 and later.
 432          */
 433         ent->salttype = NULL;
 434 #endif
 435         krb5_copy_data(context, &key->salt->salt,
 436                        &ent->salt);
 437     } else {
 438         /* we return no salt type at all, as that should indicate
 439          * the default salt type and make everybody happy.  some
 440          * systems (like w2k) dislike being told the salt type
 441          * here. */
 442
 443         ent->salttype = NULL;
 444         ent->salt = NULL;
 445     }
 446     return 0;
 447 }
 448
 449 static krb5_error_code
 450 get_pa_etype_info(krb5_context context,
 451                   krb5_kdc_configuration *config,
 452                   METHOD_DATA *md, Key *ckey)
 453 {
 454     krb5_error_code ret = 0;
 455     ETYPE_INFO pa;
 456     unsigned char *buf;
 457     size_t len;
 458
 459
 460     pa.len = 1;
 461     pa.val = calloc(1, sizeof(pa.val[0]));
 462     if(pa.val == NULL)
 463         return ENOMEM;
 464
 465     ret = make_etype_info_entry(context, &pa.val[0], ckey);
 466     if (ret) {
 467         free_ETYPE_INFO(&pa);
 468         return ret;
 469     }
 470
 471     ASN1_MALLOC_ENCODE(ETYPE_INFO, buf, len, &pa, &len, ret);
 472     free_ETYPE_INFO(&pa);
 473     if(ret)
 474         return ret;
 475     ret = realloc_method_data(md);
 476     if(ret) {
 477         free(buf);
 478         return ret;
 479     }
 480     md->val[md->len - 1].padata_type = KRB5_PADATA_ETYPE_INFO;
 481     md->val[md->len - 1].padata_value.length = len;
 482     md->val[md->len - 1].padata_value.data = buf;
 483     return 0;
 484 }
 485
 486 /*
 487  *
 488  */
 489
 490 extern int _krb5_AES_string_to_default_iterator;
 491
 492 static krb5_error_code
 493 make_etype_info2_entry(ETYPE_INFO2_ENTRY *ent, Key *key)
 494 {
 495     ent->etype = key->key.keytype;
 496     if(key->salt) {
 497         ALLOC(ent->salt);
 498         if (ent->salt == NULL)
 499             return ENOMEM;
 500         *ent->salt = malloc(key->salt->salt.length + 1);
 501         if (*ent->salt == NULL) {
 502             free(ent->salt);
 503             ent->salt = NULL;
 504             return ENOMEM;
 505         }
 506         memcpy(*ent->salt, key->salt->salt.data, key->salt->salt.length);
 507         (*ent->salt)[key->salt->salt.length] = '\0';
 508     } else
 509         ent->salt = NULL;
 510
 511     ent->s2kparams = NULL;
 512
 513     switch (key->key.keytype) {
 514     case ETYPE_AES128_CTS_HMAC_SHA1_96:
 515     case ETYPE_AES256_CTS_HMAC_SHA1_96:
 516         ALLOC(ent->s2kparams);
 517         if (ent->s2kparams == NULL)
 518             return ENOMEM;
 519         ent->s2kparams->length = 4;
 520         ent->s2kparams->data = malloc(ent->s2kparams->length);
 521         if (ent->s2kparams->data == NULL) {
 522             free(ent->s2kparams);
 523             ent->s2kparams = NULL;
 524             return ENOMEM;
 525         }
 526         _krb5_put_int(ent->s2kparams->data,
 527                       _krb5_AES_string_to_default_iterator,
 528                       ent->s2kparams->length);
 529         break;
 530     case ETYPE_DES_CBC_CRC:
 531     case ETYPE_DES_CBC_MD4:
 532     case ETYPE_DES_CBC_MD5:
 533         /* Check if this was a AFS3 salted key */
 534         if(key->salt && key->salt->type == hdb_afs3_salt){
 535             ALLOC(ent->s2kparams);
 536             if (ent->s2kparams == NULL)
 537                 return ENOMEM;
 538             ent->s2kparams->length = 1;
 539             ent->s2kparams->data = malloc(ent->s2kparams->length);
 540             if (ent->s2kparams->data == NULL) {
 541                 free(ent->s2kparams);
 542                 ent->s2kparams = NULL;
 543                 return ENOMEM;
 544             }
 545             _krb5_put_int(ent->s2kparams->data,
 546                           1,
 547                           ent->s2kparams->length);
 548         }
 549         break;
 550     default:
 551         break;
 552     }
 553     return 0;
 554 }
 555
 556 /*
 557  * Return an ETYPE-INFO2. Enctypes are storted the same way as in the
 558  * database (client supported enctypes first, then the unsupported
 559  * enctypes).
 560  */
 561
 562 static krb5_error_code
 563 get_pa_etype_info2(krb5_context context,
 564                    krb5_kdc_configuration *config,
 565                    METHOD_DATA *md, Key *ckey)
 566 {
 567     krb5_error_code ret = 0;
 568     ETYPE_INFO2 pa;
 569     unsigned char *buf;
 570     size_t len;
 571
 572     pa.len = 1;
 573     pa.val = calloc(1, sizeof(pa.val[0]));
 574     if(pa.val == NULL)
 575         return ENOMEM;
 576
 577     ret = make_etype_info2_entry(&pa.val[0], ckey);
 578     if (ret) {
 579         free_ETYPE_INFO2(&pa);
 580         return ret;
 581     }
 582
 583     ASN1_MALLOC_ENCODE(ETYPE_INFO2, buf, len, &pa, &len, ret);
 584     free_ETYPE_INFO2(&pa);
 585     if(ret)
 586         return ret;
 587     ret = realloc_method_data(md);
 588     if(ret) {
 589         free(buf);
 590         return ret;
 591     }
 592     md->val[md->len - 1].padata_type = KRB5_PADATA_ETYPE_INFO2;
 593     md->val[md->len - 1].padata_value.length = len;
 594     md->val[md->len - 1].padata_value.data = buf;
 595     return 0;
 596 }
 597
 598 /*
 599  *
 600  */
 601
 602 static void
 603 log_as_req(krb5_context context,
 604            krb5_kdc_configuration *config,
 605            krb5_enctype cetype,
 606            krb5_enctype setype,
 607            const KDC_REQ_BODY *b)
 608 {
 609     krb5_error_code ret;
 610     struct rk_strpool *p;
 611     char *str;
 612     int i;
 613
 614     p = rk_strpoolprintf(NULL, "%s", "Client supported enctypes: ");
 615
 616     for (i = 0; i < b->etype.len; i++) {
 617         ret = krb5_enctype_to_string(context, b->etype.val[i], &str);
 618         if (ret == 0) {
 619             p = rk_strpoolprintf(p, "%s", str);
 620             free(str);
 621         } else
 622             p = rk_strpoolprintf(p, "%d", b->etype.val[i]);
 623         if (p && i + 1 < b->etype.len)
 624             p = rk_strpoolprintf(p, ", ");
 625         if (p == NULL) {
 626             kdc_log(context, config, 0, "out of memory");
 627             return;
 628         }
 629     }
 630     if (p == NULL)
 631         p = rk_strpoolprintf(p, "no encryption types");
 632
 633     {
 634         char *cet;
 635         char *set;
 636
 637         ret = krb5_enctype_to_string(context, cetype, &cet);
 638         if(ret == 0) {
 639             ret = krb5_enctype_to_string(context, setype, &set);
 640             if (ret == 0) {
 641                 p = rk_strpoolprintf(p, ", using %s/%s", cet, set);
 642                 free(set);
 643             }
 644             free(cet);
 645         }
 646         if (ret != 0)
 647             p = rk_strpoolprintf(p, ", using enctypes %d/%d",
 648                                  cetype, setype);
 649     }
 650
 651     str = rk_strpoolcollect(p);
 652     kdc_log(context, config, 0, "%s", str);
 653     free(str);
 654
 655     {
 656         char fixedstr[128];
 657         unparse_flags(KDCOptions2int(b->kdc_options), asn1_KDCOptions_units(),
 658                       fixedstr, sizeof(fixedstr));
 659         if(*fixedstr)
 660             kdc_log(context, config, 0, "Requested flags: %s", fixedstr);
 661     }
 662 }
 663
 664 /*
 665  * verify the flags on `client' and `server', returning 0
 666  * if they are OK and generating an error messages and returning
 667  * and error code otherwise.
 668  */
 669
 670 krb5_error_code
 671 kdc_check_flags(krb5_context context,
 672                 krb5_kdc_configuration *config,
 673                 hdb_entry_ex *client_ex, const char *client_name,
 674                 hdb_entry_ex *server_ex, const char *server_name,
 675                 krb5_boolean is_as_req)
 676 {
 677     if(client_ex != NULL) {
 678         hdb_entry *client = &client_ex->entry;
 679
 680         /* check client */
 681         if (client->flags.locked_out) {
 682             kdc_log(context, config, 0,
 683                     "Client (%s) is locked out", client_name);
 684             return KRB5KDC_ERR_POLICY;
 685         }
 686
 687         if (client->flags.invalid) {
 688             kdc_log(context, config, 0,
 689                     "Client (%s) has invalid bit set", client_name);
 690             return KRB5KDC_ERR_POLICY;
 691         }
 692
 693         if(!client->flags.client){
 694             kdc_log(context, config, 0,
 695                     "Principal may not act as client -- %s", client_name);
 696             return KRB5KDC_ERR_POLICY;
 697         }
 698
 699         if (client->valid_start && *client->valid_start > kdc_time) {
 700             char starttime_str[100];
 701             krb5_format_time(context, *client->valid_start,
 702                              starttime_str, sizeof(starttime_str), TRUE);
 703             kdc_log(context, config, 0,
 704                     "Client not yet valid until %s -- %s",
 705                     starttime_str, client_name);
 706             return KRB5KDC_ERR_CLIENT_NOTYET;
 707         }
 708
 709         if (client->valid_end && *client->valid_end < kdc_time) {
 710             char endtime_str[100];
 711             krb5_format_time(context, *client->valid_end,
 712                              endtime_str, sizeof(endtime_str), TRUE);
 713             kdc_log(context, config, 0,
 714                     "Client expired at %s -- %s",
 715                     endtime_str, client_name);
 716             return KRB5KDC_ERR_NAME_EXP;
 717         }
 718
 719         if (client->pw_end && *client->pw_end < kdc_time
 720             && (server_ex == NULL || !server_ex->entry.flags.change_pw)) {
 721             char pwend_str[100];
 722             krb5_format_time(context, *client->pw_end,
 723                              pwend_str, sizeof(pwend_str), TRUE);
 724             kdc_log(context, config, 0,
 725                     "Client's key has expired at %s -- %s",
 726                     pwend_str, client_name);
 727             return KRB5KDC_ERR_KEY_EXPIRED;
 728         }
 729     }
 730
 731     /* check server */
 732
 733     if (server_ex != NULL) {
 734         hdb_entry *server = &server_ex->entry;
 735
 736         if (server->flags.locked_out) {
 737             kdc_log(context, config, 0,
 738                     "Client server locked out -- %s", server_name);
 739             return KRB5KDC_ERR_POLICY;
 740         }
 741         if (server->flags.invalid) {
 742             kdc_log(context, config, 0,
 743                     "Server has invalid flag set -- %s", server_name);
 744             return KRB5KDC_ERR_POLICY;
 745         }
 746
 747         if(!server->flags.server){
 748             kdc_log(context, config, 0,
 749                     "Principal may not act as server -- %s", server_name);
 750             return KRB5KDC_ERR_POLICY;
 751         }
 752
 753         if(!is_as_req && server->flags.initial) {
 754             kdc_log(context, config, 0,
 755                     "AS-REQ is required for server -- %s", server_name);
 756             return KRB5KDC_ERR_POLICY;
 757         }
 758
 759         if (server->valid_start && *server->valid_start > kdc_time) {
 760             char starttime_str[100];
 761             krb5_format_time(context, *server->valid_start,
 762                              starttime_str, sizeof(starttime_str), TRUE);
 763             kdc_log(context, config, 0,
 764                     "Server not yet valid until %s -- %s",
 765                     starttime_str, server_name);
 766             return KRB5KDC_ERR_SERVICE_NOTYET;
 767         }
 768
 769         if (server->valid_end && *server->valid_end < kdc_time) {
 770             char endtime_str[100];
 771             krb5_format_time(context, *server->valid_end,
 772                              endtime_str, sizeof(endtime_str), TRUE);
 773             kdc_log(context, config, 0,
 774                     "Server expired at %s -- %s",
 775                     endtime_str, server_name);
 776             return KRB5KDC_ERR_SERVICE_EXP;
 777         }
 778
 779         if (server->pw_end && *server->pw_end < kdc_time) {
 780             char pwend_str[100];
 781             krb5_format_time(context, *server->pw_end,
 782                              pwend_str, sizeof(pwend_str), TRUE);
 783             kdc_log(context, config, 0,
 784                     "Server's key has expired at -- %s",
 785                     pwend_str, server_name);
 786             return KRB5KDC_ERR_KEY_EXPIRED;
 787         }
 788     }
 789     return 0;
 790 }
 791
 792 /*
 793  * Return TRUE if `from' is part of `addresses' taking into consideration
 794  * the configuration variables that tells us how strict we should be about
 795  * these checks
 796  */
 797
 798 krb5_boolean
 799 _kdc_check_addresses(krb5_context context,
 800                      krb5_kdc_configuration *config,
 801                      HostAddresses *addresses, const struct sockaddr *from)
 802 {
 803     krb5_error_code ret;
 804     krb5_address addr;
 805     krb5_boolean result;
 806     krb5_boolean only_netbios = TRUE;
 807     int i;
 808
 809     if(config->check_ticket_addresses == 0)
 810         return TRUE;
 811
 812     if(addresses == NULL)
 813         return config->allow_null_ticket_addresses;
 814
 815     for (i = 0; i < addresses->len; ++i) {
 816         if (addresses->val[i].addr_type != KRB5_ADDRESS_NETBIOS) {
 817             only_netbios = FALSE;
 818         }
 819     }
 820
 821     /* Windows sends it's netbios name, which I can only assume is
 822      * used for the 'allowed workstations' check.  This is painful,
 823      * but we still want to check IP addresses if they happen to be
 824      * present.
 825      */
 826
 827     if(only_netbios)
 828         return config->allow_null_ticket_addresses;
 829
 830     ret = krb5_sockaddr2address (context, from, &addr);
 831     if(ret)
 832         return FALSE;
 833
 834     result = krb5_address_search(context, &addr, addresses);
 835     krb5_free_address (context, &addr);
 836     return result;
 837 }
 838
 839 /*
 840  *
 841  */
 842
 843 static krb5_boolean
 844 send_pac_p(krb5_context context, KDC_REQ *req)
 845 {
 846     krb5_error_code ret;
 847     PA_PAC_REQUEST pacreq;
 848     const PA_DATA *pa;
 849     int i = 0;
 850
 851     pa = _kdc_find_padata(req, &i, KRB5_PADATA_PA_PAC_REQUEST);
 852     if (pa == NULL)
 853         return TRUE;
 854
 855     ret = decode_PA_PAC_REQUEST(pa->padata_value.data,
 856                                 pa->padata_value.length,
 857                                 &pacreq,
 858                                 NULL);
 859     if (ret)
 860         return TRUE;
 861     i = pacreq.include_pac;
 862     free_PA_PAC_REQUEST(&pacreq);
 863     if (i == 0)
 864         return FALSE;
 865     return TRUE;
 866 }
 867
 868 krb5_boolean
 869 _kdc_is_anonymous(krb5_context context, krb5_principal principal)
 870 {
 871     if (principal->name.name_type != KRB5_NT_WELLKNOWN ||
 872         principal->name.name_string.len != 2 ||
 873         strcmp(principal->name.name_string.val[0], KRB5_WELLKNOWN_NAME) != 0 ||
 874         strcmp(principal->name.name_string.val[1], KRB5_ANON_NAME) != 0)
 875         return 0;
 876     return 1;
 877 }
 878
 879 /*
 880  *
 881  */
 882
 883 krb5_error_code
 884 _kdc_as_rep(krb5_context context,
 885             krb5_kdc_configuration *config,
 886             KDC_REQ *req,
 887             const krb5_data *req_buffer,
 888             krb5_data *reply,
 889             const char *from,
 890             struct sockaddr *from_addr,
 891             int datagram_reply)
 892 {
 893     KDC_REQ_BODY *b = &req->req_body;
 894     AS_REP rep;
 895     KDCOptions f = b->kdc_options;
 896     hdb_entry_ex *client = NULL, *server = NULL;
 897     krb5_enctype cetype, setype, sessionetype;
 898     krb5_data e_data;
 899     EncTicketPart et;
 900     EncKDCRepPart ek;
 901     krb5_principal client_princ = NULL, server_princ = NULL;
 902     char *client_name = NULL, *server_name = NULL;
 903     krb5_error_code ret = 0;
 904     const char *e_text = NULL;
 905     krb5_crypto crypto;
 906     Key *ckey, *skey;
 907     EncryptionKey *reply_key;
 908     int flags = 0;
 909 #ifdef PKINIT
 910     pk_client_params *pkp = NULL;
 911 #endif
 912
 913     memset(&rep, 0, sizeof(rep));
 914     krb5_data_zero(&e_data);
 915
 916     if (f.canonicalize)
 917         flags |= HDB_F_CANON;
 918
 919     if(b->sname == NULL){
 920         ret = KRB5KRB_ERR_GENERIC;
 921         e_text = "No server in request";
 922     } else{
 923         ret = _krb5_principalname2krb5_principal (context,
 924                                                   &server_princ,
 925                                                   *(b->sname),
 926                                                   b->realm);
 927         if (ret == 0)
 928             ret = krb5_unparse_name(context, server_princ, &server_name);
 929     }
 930     if (ret) {
 931         kdc_log(context, config, 0,
 932                 "AS-REQ malformed server name from %s", from);
 933         goto out;
 934     }
 935     if(b->cname == NULL){
 936         ret = KRB5KRB_ERR_GENERIC;
 937         e_text = "No client in request";
 938     } else {
 939         ret = _krb5_principalname2krb5_principal (context,
 940                                                   &client_princ,
 941                                                   *(b->cname),
 942                                                   b->realm);
 943         if (ret)
 944             goto out;
 945
 946         ret = krb5_unparse_name(context, client_princ, &client_name);
 947     }
 948     if (ret) {
 949         kdc_log(context, config, 0,
 950                 "AS-REQ malformed client name from %s", from);
 951         goto out;
 952     }
 953
 954     kdc_log(context, config, 0, "AS-REQ %s from %s for %s",
 955             client_name, from, server_name);
 956
 957     /*
 958      *
 959      */
 960
 961     if (_kdc_is_anonymous(context, client_princ)) {
 962         if (!b->kdc_options.request_anonymous) {
 963             kdc_log(context, config, 0, "Anonymous ticket w/o anonymous flag");
 964             ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 965             goto out;
 966         }
 967     } else if (b->kdc_options.request_anonymous) {
 968         kdc_log(context, config, 0,
 969                 "Request for a anonymous ticket with non "
 970                 "anonymous client name: %s", client_name);
 971         ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 972         goto out;
 973     }
 974
 975     /*
 976      *
 977      */
 978
 979     ret = _kdc_db_fetch(context, config, client_princ,
 980                         HDB_F_GET_CLIENT | flags, NULL, &client);
 981     if(ret){
 982         kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name,
 983                 krb5_get_err_text(context, ret));
 984         ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 985         goto out;
 986     }
 987
 988     ret = _kdc_db_fetch(context, config, server_princ,
 989                         HDB_F_GET_SERVER|HDB_F_GET_KRBTGT,
 990                         NULL, &server);
 991     if(ret){
 992         kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name,
 993                 krb5_get_err_text(context, ret));
 994         ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
 995         goto out;
 996     }
 997
 998     memset(&et, 0, sizeof(et));
 999     memset(&ek, 0, sizeof(ek));
1000
1001     /*
1002      * Find the client key for reply encryption and pa-type salt, Pick
1003      * the client key upfront before the other keys because that is
1004      * going to affect what enctypes we are going to use in
1005      * ETYPE-INFO{,2}.
1006      */
1007
1008     ret = _kdc_find_etype(context, client, b->etype.val, b->etype.len,
1009                           &ckey, &cetype);
1010     if (ret) {
1011         kdc_log(context, config, 0,
1012                 "Client (%s) has no support for etypes", client_name);
1013         goto out;
1014     }
1015
1016     /*
1017      * Pre-auth processing
1018      */
1019
1020     if(req->padata){
1021         int i;
1022         const PA_DATA *pa;
1023         int found_pa = 0;
1024
1025         log_patypes(context, config, req->padata);
1026
1027 #ifdef PKINIT
1028         kdc_log(context, config, 5,
1029                 "Looking for PKINIT pa-data -- %s", client_name);
1030
1031         e_text = "No PKINIT PA found";
1032
1033         i = 0;
1034         pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ);
1035         if (pa == NULL) {
1036             i = 0;
1037             pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN);
1038         }
1039         if (pa) {
1040             char *client_cert = NULL;
1041
1042             ret = _kdc_pk_rd_padata(context, config, req, pa, client, &pkp);
1043             if (ret) {
1044                 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
1045                 kdc_log(context, config, 5,
1046                         "Failed to decode PKINIT PA-DATA -- %s",
1047                         client_name);
1048                 goto ts_enc;
1049             }
1050             if (ret == 0 && pkp == NULL)
1051                 goto ts_enc;
1052
1053             ret = _kdc_pk_check_client(context,
1054                                        config,
1055                                        client,
1056                                        pkp,
1057                                        &client_cert);
1058             if (ret) {
1059                 e_text = "PKINIT certificate not allowed to "
1060                     "impersonate principal";
1061                 _kdc_pk_free_client_param(context, pkp);
1062
1063                 kdc_log(context, config, 0, "%s", e_text);
1064                 pkp = NULL;
1065                 goto out;
1066             }
1067
1068             found_pa = 1;
1069             et.flags.pre_authent = 1;
1070             kdc_log(context, config, 0,
1071                     "PKINIT pre-authentication succeeded -- %s using %s",
1072                     client_name, client_cert);
1073             free(client_cert);
1074             if (pkp)
1075                 goto preauth_done;
1076         }
1077     ts_enc:
1078 #endif
1079         kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s",
1080                 client_name);
1081
1082         i = 0;
1083         e_text = "No ENC-TS found";
1084         while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){
1085             krb5_data ts_data;
1086             PA_ENC_TS_ENC p;
1087             size_t len;
1088             EncryptedData enc_data;
1089             Key *pa_key;
1090             char *str;
1091
1092             found_pa = 1;
1093
1094             if (b->kdc_options.request_anonymous) {
1095                 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
1096                 kdc_log(context, config, 0, "ENC-TS doesn't support anon");
1097                 goto out;
1098             }
1099
1100             ret = decode_EncryptedData(pa->padata_value.data,
1101                                        pa->padata_value.length,
1102                                        &enc_data,
1103                                        &len);
1104             if (ret) {
1105                 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
1106                 kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s",
1107                         client_name);
1108                 goto out;
1109             }
1110
1111             ret = hdb_enctype2key(context, &client->entry,
1112                                   enc_data.etype, &pa_key);
1113             if(ret){
1114                 char *estr;
1115                 e_text = "No key matches pa-data";
1116                 ret = KRB5KDC_ERR_ETYPE_NOSUPP;
1117                 if(krb5_enctype_to_string(context, enc_data.etype, &estr))
1118                     estr = NULL;
1119                 if(estr == NULL)
1120                     kdc_log(context, config, 5,
1121                             "No client key matching pa-data (%d) -- %s",
1122                             enc_data.etype, client_name);
1123                 else
1124                     kdc_log(context, config, 5,
1125                             "No client key matching pa-data (%s) -- %s",
1126                             estr, client_name);
1127                 free(estr);
1128
1129                 free_EncryptedData(&enc_data);
1130                 continue;
1131             }
1132
1133         try_next_key:
1134             ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto);
1135             if (ret) {
1136                 kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
1137                         krb5_get_err_text(context, ret));
1138                 free_EncryptedData(&enc_data);
1139                 continue;
1140             }
1141
1142             ret = krb5_decrypt_EncryptedData (context,
1143                                               crypto,
1144                                               KRB5_KU_PA_ENC_TIMESTAMP,
1145                                               &enc_data,
1146                                               &ts_data);
1147             krb5_crypto_destroy(context, crypto);
1148             /*
1149              * Since the user might have several keys with the same
1150              * enctype but with diffrent salting, we need to try all
1151              * the keys with the same enctype.
1152              */
1153             if(ret){
1154                 krb5_error_code ret2;
1155                 ret2 = krb5_enctype_to_string(context,
1156                                               pa_key->key.keytype, &str);
1157                 if (ret2)
1158                     str = NULL;
1159                 kdc_log(context, config, 5,
1160                         "Failed to decrypt PA-DATA -- %s "
1161                         "(enctype %s) error %s",
1162                         client_name,
1163                         str ? str : "unknown enctype",
1164                         krb5_get_err_text(context, ret));
1165                 free(str);
1166
1167                 if(hdb_next_enctype2key(context, &client->entry,
1168                                         enc_data.etype, &pa_key) == 0)
1169                     goto try_next_key;
1170                 e_text = "Failed to decrypt PA-DATA";
1171
1172                 free_EncryptedData(&enc_data);
1173                 ret = KRB5KDC_ERR_PREAUTH_FAILED;
1174                 continue;
1175             }
1176             free_EncryptedData(&enc_data);
1177             ret = decode_PA_ENC_TS_ENC(ts_data.data,
1178                                        ts_data.length,
1179                                        &p,
1180                                        &len);
1181             krb5_data_free(&ts_data);
1182             if(ret){
1183                 e_text = "Failed to decode PA-ENC-TS-ENC";
1184                 ret = KRB5KDC_ERR_PREAUTH_FAILED;
1185                 kdc_log(context, config,
1186                         5, "Failed to decode PA-ENC-TS_ENC -- %s",
1187                         client_name);
1188                 continue;
1189             }
1190             free_PA_ENC_TS_ENC(&p);
1191             if (abs(kdc_time - p.patimestamp) > context->max_skew) {
1192                 char client_time[100];
1193
1194                 krb5_format_time(context, p.patimestamp,
1195                                  client_time, sizeof(client_time), TRUE);
1196
1197                 ret = KRB5KRB_AP_ERR_SKEW;
1198                 kdc_log(context, config, 0,
1199                         "Too large time skew, "
1200                         "client time %s is out by %u > %u seconds -- %s",
1201                         client_time,
1202                         (unsigned)abs(kdc_time - p.patimestamp),
1203                         context->max_skew,
1204                         client_name);
1205 #if 0
1206                 /* This code is from samba, needs testing */
1207                 /*
1208                  * the following is needed to make windows clients
1209                  * to retry using the timestamp in the error message
1210                  *
1211                  * this is maybe a bug in windows to not trying when e_text
1212                  * is present...
1213                  */
1214                 e_text = NULL;
1215 #else
1216                 e_text = "Too large time skew";
1217 #endif
1218                 goto out;
1219             }
1220             et.flags.pre_authent = 1;
1221
1222             ret = krb5_enctype_to_string(context,pa_key->key.keytype, &str);
1223             if (ret)
1224                 str = NULL;
1225
1226             kdc_log(context, config, 2,
1227                     "ENC-TS Pre-authentication succeeded -- %s using %s",
1228                     client_name, str ? str : "unknown enctype");
1229             free(str);
1230             break;
1231         }
1232 #ifdef PKINIT
1233     preauth_done:
1234 #endif
1235         if(found_pa == 0 && config->require_preauth)
1236             goto use_pa;
1237         /* We come here if we found a pa-enc-timestamp, but if there
1238            was some problem with it, other than too large skew */
1239         if(found_pa && et.flags.pre_authent == 0){
1240             kdc_log(context, config, 0, "%s -- %s", e_text, client_name);
1241             e_text = NULL;
1242             goto out;
1243         }
1244     }else if (config->require_preauth
1245               || b->kdc_options.request_anonymous /* hack to force anon */
1246               || client->entry.flags.require_preauth
1247               || server->entry.flags.require_preauth) {
1248         METHOD_DATA method_data;
1249         PA_DATA *pa;
1250         unsigned char *buf;
1251         size_t len;
1252
1253     use_pa:
1254         method_data.len = 0;
1255         method_data.val = NULL;
1256
1257         ret = realloc_method_data(&method_data);
1258         if (ret) {
1259             free_METHOD_DATA(&method_data);
1260             goto out;
1261         }
1262         pa = &method_data.val[method_data.len-1];
1263         pa->padata_type         = KRB5_PADATA_ENC_TIMESTAMP;
1264         pa->padata_value.length = 0;
1265         pa->padata_value.data   = NULL;
1266
1267 #ifdef PKINIT
1268         ret = realloc_method_data(&method_data);
1269         if (ret) {
1270             free_METHOD_DATA(&method_data);
1271             goto out;
1272         }
1273         pa = &method_data.val[method_data.len-1];
1274         pa->padata_type         = KRB5_PADATA_PK_AS_REQ;
1275         pa->padata_value.length = 0;
1276         pa->padata_value.data   = NULL;
1277
1278         ret = realloc_method_data(&method_data);
1279         if (ret) {
1280             free_METHOD_DATA(&method_data);
1281             goto out;
1282         }
1283         pa = &method_data.val[method_data.len-1];
1284         pa->padata_type         = KRB5_PADATA_PK_AS_REQ_WIN;
1285         pa->padata_value.length = 0;
1286         pa->padata_value.data   = NULL;
1287 #endif
1288
1289         /*
1290          * If there is a client key, send ETYPE_INFO{,2}
1291          */
1292         if (ckey) {
1293
1294             /*
1295              * RFC4120 requires:
1296              * - If the client only knows about old enctypes, then send
1297              *   both info replies (we send 'info' first in the list).
1298              * - If the client is 'modern', because it knows about 'new'
1299              *   enctype types, then only send the 'info2' reply.
1300              *
1301              * Before we send the full list of etype-info data, we pick
1302              * the client key we would have used anyway below, just pick
1303              * that instead.
1304              */
1305
1306             if (older_enctype(ckey->key.keytype)) {
1307                 ret = get_pa_etype_info(context, config,
1308                                         &method_data, ckey);
1309                 if (ret) {
1310                     free_METHOD_DATA(&method_data);
1311                     goto out;
1312                 }
1313             }
1314             ret = get_pa_etype_info2(context, config,
1315                                      &method_data, ckey);
1316             if (ret) {
1317                 free_METHOD_DATA(&method_data);
1318                 goto out;
1319             }
1320         }
1321
1322         ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret);
1323         free_METHOD_DATA(&method_data);
1324
1325         e_data.data   = buf;
1326         e_data.length = len;
1327         e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ",
1328
1329         ret = KRB5KDC_ERR_PREAUTH_REQUIRED;
1330
1331         kdc_log(context, config, 0,
1332                 "No preauth found, returning PREAUTH-REQUIRED -- %s",
1333                 client_name);
1334         goto out;
1335     }
1336
1337     /*
1338      * Verify flags after the user been required to prove its identity
1339      * with in a preauth mech.
1340      */
1341
1342     ret = _kdc_check_access(context, config, client, client_name,
1343                             server, server_name,
1344                             req, &e_data);
1345     if(ret)
1346         goto out;
1347
1348     /*
1349      * Selelct the best encryption type for the KDC with out regard to
1350      * the client since the client never needs to read that data.
1351      */
1352
1353     ret = _kdc_get_preferred_key(context, config,
1354                                  server, server_name,
1355                                  &setype, &skey);
1356     if(ret)
1357         goto out;
1358
1359     /*
1360      * Select a session enctype from the list of the crypto systems
1361      * supported enctype, is supported by the client and is one of the
1362      * enctype of the enctype of the krbtgt.
1363      *
1364      * The later is used as a hint what enctype all KDC are supporting
1365      * to make sure a newer version of KDC wont generate a session
1366      * enctype that and older version of a KDC in the same realm can't
1367      * decrypt.
1368      *
1369      * But if the KDC admin is paranoid and doesn't want to have "no
1370      * the best" enctypes on the krbtgt, lets save the best pick from
1371      * the client list and hope that that will work for any other
1372      * KDCs.
1373      */
1374     {
1375         const krb5_enctype *p;
1376         krb5_enctype clientbest = ETYPE_NULL;
1377         int i, j;
1378
1379         p = krb5_kerberos_enctypes(context);
1380
1381         sessionetype = ETYPE_NULL;
1382
1383         for (i = 0; p[i] != ETYPE_NULL && sessionetype == ETYPE_NULL; i++) {
1384             if (krb5_enctype_valid(context, p[i]) != 0)
1385                 continue;
1386
1387             for (j = 0; j < b->etype.len && sessionetype == ETYPE_NULL; j++) {
1388                 Key *dummy;
1389                 /* check with client */
1390                 if (p[i] != b->etype.val[j])
1391                     continue;
1392                 /* save best of union of { client, crypto system } */
1393                 if (clientbest == ETYPE_NULL)
1394                     clientbest = p[i];
1395                 /* check with krbtgt */
1396                 ret = hdb_enctype2key(context, &server->entry, p[i], &dummy);
1397                 if (ret)
1398                     continue;
1399                 sessionetype = p[i];
1400             }
1401         }
1402         /* if krbtgt had no shared keys with client, pick clients best */
1403         if (clientbest != ETYPE_NULL && sessionetype == ETYPE_NULL) {
1404             sessionetype = clientbest;
1405         } else if (sessionetype == ETYPE_NULL) {
1406             kdc_log(context, config, 0,
1407                     "Client (%s) from %s has no common enctypes with KDC"
1408                     "to use for the session key",
1409                     client_name, from);
1410             goto out;
1411         }
1412     }
1413
1414     log_as_req(context, config, cetype, setype, b);
1415
1416     if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey
1417        || (f.request_anonymous && !config->allow_anonymous)) {
1418         ret = KRB5KDC_ERR_BADOPTION;
1419         kdc_log(context, config, 0, "Bad KDC options -- %s", client_name);
1420         goto out;
1421     }
1422
1423     rep.pvno = 5;
1424     rep.msg_type = krb_as_rep;
1425
1426     ret = copy_Realm(&client->entry.principal->realm, &rep.crealm);
1427     if (ret)
1428         goto out;
1429     ret = _krb5_principal2principalname(&rep.cname, client->entry.principal);
1430     if (ret)
1431         goto out;
1432
1433     rep.ticket.tkt_vno = 5;
1434     copy_Realm(&server->entry.principal->realm, &rep.ticket.realm);
1435     _krb5_principal2principalname(&rep.ticket.sname,
1436                                   server->entry.principal);
1437     /* java 1.6 expects the name to be the same type, lets allow that
1438      * uncomplicated name-types. */
1439 #define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t)
1440     if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST))
1441         rep.ticket.sname.name_type = b->sname->name_type;
1442 #undef CNT
1443
1444     et.flags.initial = 1;
1445     if(client->entry.flags.forwardable && server->entry.flags.forwardable)
1446         et.flags.forwardable = f.forwardable;
1447     else if (f.forwardable) {
1448         ret = KRB5KDC_ERR_POLICY;
1449         kdc_log(context, config, 0,
1450                 "Ticket may not be forwardable -- %s", client_name);
1451         goto out;
1452     }
1453     if(client->entry.flags.proxiable && server->entry.flags.proxiable)
1454         et.flags.proxiable = f.proxiable;
1455     else if (f.proxiable) {
1456         ret = KRB5KDC_ERR_POLICY;
1457         kdc_log(context, config, 0,
1458                 "Ticket may not be proxiable -- %s", client_name);
1459         goto out;
1460     }
1461     if(client->entry.flags.postdate && server->entry.flags.postdate)
1462         et.flags.may_postdate = f.allow_postdate;
1463     else if (f.allow_postdate){
1464         ret = KRB5KDC_ERR_POLICY;
1465         kdc_log(context, config, 0,
1466                 "Ticket may not be postdatable -- %s", client_name);
1467         goto out;
1468     }
1469
1470     /* check for valid set of addresses */
1471     if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) {
1472         ret = KRB5KRB_AP_ERR_BADADDR;
1473         kdc_log(context, config, 0,
1474                 "Bad address list requested -- %s", client_name);
1475         goto out;
1476     }
1477
1478     ret = copy_PrincipalName(&rep.cname, &et.cname);
1479     if (ret)
1480         goto out;
1481     ret = copy_Realm(&rep.crealm, &et.crealm);
1482     if (ret)
1483         goto out;
1484
1485     {
1486         time_t start;
1487         time_t t;
1488
1489         start = et.authtime = kdc_time;
1490
1491         if(f.postdated && req->req_body.from){
1492             ALLOC(et.starttime);
1493             start = *et.starttime = *req->req_body.from;
1494             et.flags.invalid = 1;
1495             et.flags.postdated = 1; /* XXX ??? */
1496         }
1497         _kdc_fix_time(&b->till);
1498         t = *b->till;
1499
1500         /* be careful not overflowing */
1501
1502         if(client->entry.max_life)
1503             t = start + min(t - start, *client->entry.max_life);
1504         if(server->entry.max_life)
1505             t = start + min(t - start, *server->entry.max_life);
1506 #if 0
1507         t = min(t, start + realm->max_life);
1508 #endif
1509         et.endtime = t;
1510         if(f.renewable_ok && et.endtime < *b->till){
1511             f.renewable = 1;
1512             if(b->rtime == NULL){
1513                 ALLOC(b->rtime);
1514                 *b->rtime = 0;
1515             }
1516             if(*b->rtime < *b->till)
1517                 *b->rtime = *b->till;
1518         }
1519         if(f.renewable && b->rtime){
1520             t = *b->rtime;
1521             if(t == 0)
1522                 t = MAX_TIME;
1523             if(client->entry.max_renew)
1524                 t = start + min(t - start, *client->entry.max_renew);
1525             if(server->entry.max_renew)
1526                 t = start + min(t - start, *server->entry.max_renew);
1527 #if 0
1528             t = min(t, start + realm->max_renew);
1529 #endif
1530             ALLOC(et.renew_till);
1531             *et.renew_till = t;
1532             et.flags.renewable = 1;
1533         }
1534     }
1535
1536     if (f.request_anonymous)
1537         et.flags.anonymous = 1;
1538
1539     if(b->addresses){
1540         ALLOC(et.caddr);
1541         copy_HostAddresses(b->addresses, et.caddr);
1542     }
1543
1544     et.transited.tr_type = DOMAIN_X500_COMPRESS;
1545     krb5_data_zero(&et.transited.contents);
1546
1547     /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded
1548      * as 0 and as 0x80 (meaning indefinite length) apart, and is thus
1549      * incapable of correctly decoding SEQUENCE OF's of zero length.
1550      *
1551      * To fix this, always send at least one no-op last_req
1552      *
1553      * If there's a pw_end or valid_end we will use that,
1554      * otherwise just a dummy lr.
1555      */
1556     ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val));
1557     if (ek.last_req.val == NULL) {
1558         ret = ENOMEM;
1559         goto out;
1560     }
1561     ek.last_req.len = 0;
1562     if (client->entry.pw_end
1563         && (config->kdc_warn_pwexpire == 0
1564             || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) {
1565         ek.last_req.val[ek.last_req.len].lr_type  = LR_PW_EXPTIME;
1566         ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end;
1567         ++ek.last_req.len;
1568     }
1569     if (client->entry.valid_end) {
1570         ek.last_req.val[ek.last_req.len].lr_type  = LR_ACCT_EXPTIME;
1571         ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end;
1572         ++ek.last_req.len;
1573     }
1574     if (ek.last_req.len == 0) {
1575         ek.last_req.val[ek.last_req.len].lr_type  = LR_NONE;
1576         ek.last_req.val[ek.last_req.len].lr_value = 0;
1577         ++ek.last_req.len;
1578     }
1579     ek.nonce = b->nonce;
1580     if (client->entry.valid_end || client->entry.pw_end) {
1581         ALLOC(ek.key_expiration);
1582         if (client->entry.valid_end) {
1583             if (client->entry.pw_end)
1584                 *ek.key_expiration = min(*client->entry.valid_end,
1585                                          *client->entry.pw_end);
1586             else
1587                 *ek.key_expiration = *client->entry.valid_end;
1588         } else
1589             *ek.key_expiration = *client->entry.pw_end;
1590     } else
1591         ek.key_expiration = NULL;
1592     ek.flags = et.flags;
1593     ek.authtime = et.authtime;
1594     if (et.starttime) {
1595         ALLOC(ek.starttime);
1596         *ek.starttime = *et.starttime;
1597     }
1598     ek.endtime = et.endtime;
1599     if (et.renew_till) {
1600         ALLOC(ek.renew_till);
1601         *ek.renew_till = *et.renew_till;
1602     }
1603     copy_Realm(&rep.ticket.realm, &ek.srealm);
1604     copy_PrincipalName(&rep.ticket.sname, &ek.sname);
1605     if(et.caddr){
1606         ALLOC(ek.caddr);
1607         copy_HostAddresses(et.caddr, ek.caddr);
1608     }
1609
1610     ALLOC(rep.padata);
1611     rep.padata->len = 0;
1612     rep.padata->val = NULL;
1613
1614 #if PKINIT
1615     if (pkp) {
1616         e_text = "Failed to build PK-INIT reply";
1617         ret = _kdc_pk_mk_pa_reply(context, config, pkp, client,
1618                                   sessionetype, req, req_buffer,
1619                                   &reply_key, &et.key, rep.padata);
1620         if (ret)
1621             goto out;
1622         ret = _kdc_add_inital_verified_cas(context,
1623                                            config,
1624                                            pkp,
1625                                            &et);
1626         if (ret)
1627             goto out;
1628     } else
1629 #endif
1630     if (ckey) {
1631         reply_key = &ckey->key;
1632         ret = krb5_generate_random_keyblock(context, sessionetype, &et.key);
1633         if (ret)
1634             goto out;
1635     } else {
1636         e_text = "Client have no reply key";
1637         ret = KRB5KDC_ERR_CLIENT_NOTYET;
1638         goto out;
1639     }
1640
1641     ret = copy_EncryptionKey(&et.key, &ek.key);
1642     if (ret)
1643         goto out;
1644
1645     if (ckey)
1646         set_salt_padata (rep.padata, ckey->salt);
1647
1648     /* Add signing of alias referral */
1649     if (f.canonicalize) {
1650         PA_ClientCanonicalized canon;
1651         krb5_data data;
1652         PA_DATA pa;
1653         krb5_crypto crypto;
1654         size_t len;
1655
1656         memset(&canon, 0, sizeof(canon));
1657
1658         canon.names.requested_name = *b->cname;
1659         canon.names.mapped_name = client->entry.principal->name;
1660
1661         ASN1_MALLOC_ENCODE(PA_ClientCanonicalizedNames, data.data, data.length,
1662                            &canon.names, &len, ret);
1663         if (ret)
1664             goto out;
1665         if (data.length != len)
1666             krb5_abortx(context, "internal asn.1 error");
1667
1668         /* sign using "returned session key" */
1669         ret = krb5_crypto_init(context, &et.key, 0, &crypto);
1670         if (ret) {
1671             free(data.data);
1672             goto out;
1673         }
1674
1675         ret = krb5_create_checksum(context, crypto,
1676                                    KRB5_KU_CANONICALIZED_NAMES, 0,
1677                                    data.data, data.length,
1678                                    &canon.canon_checksum);
1679         free(data.data);
1680         krb5_crypto_destroy(context, crypto);
1681         if (ret)
1682             goto out;
1683
1684         ASN1_MALLOC_ENCODE(PA_ClientCanonicalized, data.data, data.length,
1685                            &canon, &len, ret);
1686         free_Checksum(&canon.canon_checksum);
1687         if (ret)
1688             goto out;
1689         if (data.length != len)
1690             krb5_abortx(context, "internal asn.1 error");
1691
1692         pa.padata_type = KRB5_PADATA_CLIENT_CANONICALIZED;
1693         pa.padata_value = data;
1694         ret = add_METHOD_DATA(rep.padata, &pa);
1695         free(data.data);
1696         if (ret)
1697             goto out;
1698     }
1699
1700     if (rep.padata->len == 0) {
1701         free(rep.padata);
1702         rep.padata = NULL;
1703     }
1704
1705     /* Add the PAC */
1706     if (send_pac_p(context, req)) {
1707         krb5_pac p = NULL;
1708         krb5_data data;
1709
1710         ret = _kdc_pac_generate(context, client, &p);
1711         if (ret) {
1712             kdc_log(context, config, 0, "PAC generation failed for -- %s",
1713                     client_name);
1714             goto out;
1715         }
1716         if (p != NULL) {
1717             ret = _krb5_pac_sign(context, p, et.authtime,
1718                                  client->entry.principal,
1719                                  &skey->key, /* Server key */
1720                                  &skey->key, /* FIXME: should be krbtgt key */
1721                                  &data);
1722             krb5_pac_free(context, p);
1723             if (ret) {
1724                 kdc_log(context, config, 0, "PAC signing failed for -- %s",
1725                         client_name);
1726                 goto out;
1727             }
1728
1729             ret = _kdc_tkt_add_if_relevant_ad(context, &et,
1730                                               KRB5_AUTHDATA_WIN2K_PAC,
1731                                               &data);
1732             krb5_data_free(&data);
1733             if (ret)
1734                 goto out;
1735         }
1736     }
1737
1738     _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime,
1739                        et.endtime, et.renew_till);
1740
1741     /* do this as the last thing since this signs the EncTicketPart */
1742     ret = _kdc_add_KRB5SignedPath(context,
1743                                   config,
1744                                   server,
1745                                   setype,
1746                                   NULL,
1747                                   NULL,
1748                                   &et);
1749     if (ret)
1750         goto out;
1751
1752     ret = _kdc_encode_reply(context, config,
1753                             &rep, &et, &ek, setype, server->entry.kvno,
1754                             &skey->key, client->entry.kvno,
1755                             reply_key, &e_text, reply);
1756     free_EncTicketPart(&et);
1757     free_EncKDCRepPart(&ek);
1758     if (ret)
1759         goto out;
1760
1761     /* */
1762     if (datagram_reply && reply->length > config->max_datagram_reply_length) {
1763         krb5_data_free(reply);
1764         ret = KRB5KRB_ERR_RESPONSE_TOO_BIG;
1765         e_text = "Reply packet too large";
1766     }
1767
1768 out:
1769     free_AS_REP(&rep);
1770     if(ret){
1771         krb5_mk_error(context,
1772                       ret,
1773                       e_text,
1774                       (e_data.data ? &e_data : NULL),
1775                       client_princ,
1776                       server_princ,
1777                       NULL,
1778                       NULL,
1779                       reply);
1780         ret = 0;
1781     }
1782 #ifdef PKINIT
1783     if (pkp)
1784         _kdc_pk_free_client_param(context, pkp);
1785 #endif
1786     if (e_data.data)
1787         free(e_data.data);
1788     if (client_princ)
1789         krb5_free_principal(context, client_princ);
1790     free(client_name);
1791     if (server_princ)
1792         krb5_free_principal(context, server_princ);
1793     free(server_name);
1794     if(client)
1795         _kdc_free_ent(context, client);
1796     if(server)
1797         _kdc_free_ent(context, server);
1798     return ret;
1799 }
1800
1801 /*
1802  * Add the AuthorizationData `data´ of `type´ to the last element in
1803  * the sequence of authorization_data in `tkt´ wrapped in an IF_RELEVANT
1804  */
1805
1806 krb5_error_code
1807 _kdc_tkt_add_if_relevant_ad(krb5_context context,
1808                             EncTicketPart *tkt,
1809                             int type,
1810                             const krb5_data *data)
1811 {
1812     krb5_error_code ret;
1813     size_t size;
1814
1815     if (tkt->authorization_data == NULL) {
1816         tkt->authorization_data = calloc(1, sizeof(*tkt->authorization_data));
1817         if (tkt->authorization_data == NULL) {
1818             krb5_set_error_message(context, ENOMEM, "out of memory");
1819             return ENOMEM;
1820         }
1821     }
1822
1823     /* add the entry to the last element */
1824     {
1825         AuthorizationData ad = { 0, NULL };
1826         AuthorizationDataElement ade;
1827
1828         ade.ad_type = type;
1829         ade.ad_data = *data;
1830
1831         ret = add_AuthorizationData(&ad, &ade);
1832         if (ret) {
1833             krb5_set_error_message(context, ret, "add AuthorizationData failed");
1834             return ret;
1835         }
1836
1837         ade.ad_type = KRB5_AUTHDATA_IF_RELEVANT;
1838
1839         ASN1_MALLOC_ENCODE(AuthorizationData,
1840                            ade.ad_data.data, ade.ad_data.length,
1841                            &ad, &size, ret);
1842         free_AuthorizationData(&ad);
1843         if (ret) {
1844             krb5_set_error_message(context, ret, "ASN.1 encode of "
1845                                    "AuthorizationData failed");
1846             return ret;
1847         }
1848         if (ade.ad_data.length != size)
1849             krb5_abortx(context, "internal asn.1 encoder error");
1850
1851         ret = add_AuthorizationData(tkt->authorization_data, &ade);
1852         der_free_octet_string(&ade.ad_data);
1853         if (ret) {
1854             krb5_set_error_message(context, ret, "add AuthorizationData failed");
1855             return ret;
1856         }
1857     }
1858
1859     return 0;
1860 }