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.invalid) {
 682             kdc_log(context, config, 0,
 683                     "Client (%s) has invalid bit set", client_name);
 684             return KRB5KDC_ERR_POLICY;
 685         }
 686
 687         if(!client->flags.client){
 688             kdc_log(context, config, 0,
 689                     "Principal may not act as client -- %s", client_name);
 690             return KRB5KDC_ERR_POLICY;
 691         }
 692
 693         if (client->valid_start && *client->valid_start > kdc_time) {
 694             char starttime_str[100];
 695             krb5_format_time(context, *client->valid_start,
 696                              starttime_str, sizeof(starttime_str), TRUE);
 697             kdc_log(context, config, 0,
 698                     "Client not yet valid until %s -- %s",
 699                     starttime_str, client_name);
 700             return KRB5KDC_ERR_CLIENT_NOTYET;
 701         }
 702
 703         if (client->valid_end && *client->valid_end < kdc_time) {
 704             char endtime_str[100];
 705             krb5_format_time(context, *client->valid_end,
 706                              endtime_str, sizeof(endtime_str), TRUE);
 707             kdc_log(context, config, 0,
 708                     "Client expired at %s -- %s",
 709                     endtime_str, client_name);
 710             return KRB5KDC_ERR_NAME_EXP;
 711         }
 712
 713         if (client->pw_end && *client->pw_end < kdc_time
 714             && (server_ex == NULL || !server_ex->entry.flags.change_pw)) {
 715             char pwend_str[100];
 716             krb5_format_time(context, *client->pw_end,
 717                              pwend_str, sizeof(pwend_str), TRUE);
 718             kdc_log(context, config, 0,
 719                     "Client's key has expired at %s -- %s",
 720                     pwend_str, client_name);
 721             return KRB5KDC_ERR_KEY_EXPIRED;
 722         }
 723     }
 724
 725     /* check server */
 726
 727     if (server_ex != NULL) {
 728         hdb_entry *server = &server_ex->entry;
 729
 730         if (server->flags.invalid) {
 731             kdc_log(context, config, 0,
 732                     "Server has invalid flag set -- %s", server_name);
 733             return KRB5KDC_ERR_POLICY;
 734         }
 735
 736         if(!server->flags.server){
 737             kdc_log(context, config, 0,
 738                     "Principal may not act as server -- %s", server_name);
 739             return KRB5KDC_ERR_POLICY;
 740         }
 741
 742         if(!is_as_req && server->flags.initial) {
 743             kdc_log(context, config, 0,
 744                     "AS-REQ is required for server -- %s", server_name);
 745             return KRB5KDC_ERR_POLICY;
 746         }
 747
 748         if (server->valid_start && *server->valid_start > kdc_time) {
 749             char starttime_str[100];
 750             krb5_format_time(context, *server->valid_start,
 751                              starttime_str, sizeof(starttime_str), TRUE);
 752             kdc_log(context, config, 0,
 753                     "Server not yet valid until %s -- %s",
 754                     starttime_str, server_name);
 755             return KRB5KDC_ERR_SERVICE_NOTYET;
 756         }
 757
 758         if (server->valid_end && *server->valid_end < kdc_time) {
 759             char endtime_str[100];
 760             krb5_format_time(context, *server->valid_end,
 761                              endtime_str, sizeof(endtime_str), TRUE);
 762             kdc_log(context, config, 0,
 763                     "Server expired at %s -- %s",
 764                     endtime_str, server_name);
 765             return KRB5KDC_ERR_SERVICE_EXP;
 766         }
 767
 768         if (server->pw_end && *server->pw_end < kdc_time) {
 769             char pwend_str[100];
 770             krb5_format_time(context, *server->pw_end,
 771                              pwend_str, sizeof(pwend_str), TRUE);
 772             kdc_log(context, config, 0,
 773                     "Server's key has expired at -- %s",
 774                     pwend_str, server_name);
 775             return KRB5KDC_ERR_KEY_EXPIRED;
 776         }
 777     }
 778     return 0;
 779 }
 780
 781 /*
 782  * Return TRUE if `from' is part of `addresses' taking into consideration
 783  * the configuration variables that tells us how strict we should be about
 784  * these checks
 785  */
 786
 787 krb5_boolean
 788 _kdc_check_addresses(krb5_context context,
 789                      krb5_kdc_configuration *config,
 790                      HostAddresses *addresses, const struct sockaddr *from)
 791 {
 792     krb5_error_code ret;
 793     krb5_address addr;
 794     krb5_boolean result;
 795     krb5_boolean only_netbios = TRUE;
 796     int i;
 797
 798     if(config->check_ticket_addresses == 0)
 799         return TRUE;
 800
 801     if(addresses == NULL)
 802         return config->allow_null_ticket_addresses;
 803
 804     for (i = 0; i < addresses->len; ++i) {
 805         if (addresses->val[i].addr_type != KRB5_ADDRESS_NETBIOS) {
 806             only_netbios = FALSE;
 807         }
 808     }
 809
 810     /* Windows sends it's netbios name, which I can only assume is
 811      * used for the 'allowed workstations' check.  This is painful,
 812      * but we still want to check IP addresses if they happen to be
 813      * present.
 814      */
 815
 816     if(only_netbios)
 817         return config->allow_null_ticket_addresses;
 818
 819     ret = krb5_sockaddr2address (context, from, &addr);
 820     if(ret)
 821         return FALSE;
 822
 823     result = krb5_address_search(context, &addr, addresses);
 824     krb5_free_address (context, &addr);
 825     return result;
 826 }
 827
 828 /*
 829  *
 830  */
 831
 832 static krb5_boolean
 833 send_pac_p(krb5_context context, KDC_REQ *req)
 834 {
 835     krb5_error_code ret;
 836     PA_PAC_REQUEST pacreq;
 837     const PA_DATA *pa;
 838     int i = 0;
 839
 840     pa = _kdc_find_padata(req, &i, KRB5_PADATA_PA_PAC_REQUEST);
 841     if (pa == NULL)
 842         return TRUE;
 843
 844     ret = decode_PA_PAC_REQUEST(pa->padata_value.data,
 845                                 pa->padata_value.length,
 846                                 &pacreq,
 847                                 NULL);
 848     if (ret)
 849         return TRUE;
 850     i = pacreq.include_pac;
 851     free_PA_PAC_REQUEST(&pacreq);
 852     if (i == 0)
 853         return FALSE;
 854     return TRUE;
 855 }
 856
 857 krb5_boolean
 858 _kdc_is_anonymous(krb5_context context, krb5_principal principal)
 859 {
 860     if (principal->name.name_type != KRB5_NT_WELLKNOWN ||
 861         principal->name.name_string.len != 2 ||
 862         strcmp(principal->name.name_string.val[0], KRB5_WELLKNOWN_NAME) != 0 ||
 863         strcmp(principal->name.name_string.val[1], KRB5_ANON_NAME) != 0)
 864         return 0;
 865     return 1;
 866 }
 867
 868 /*
 869  *
 870  */
 871
 872 krb5_error_code
 873 _kdc_as_rep(krb5_context context,
 874             krb5_kdc_configuration *config,
 875             KDC_REQ *req,
 876             const krb5_data *req_buffer,
 877             krb5_data *reply,
 878             const char *from,
 879             struct sockaddr *from_addr,
 880             int datagram_reply)
 881 {
 882     KDC_REQ_BODY *b = &req->req_body;
 883     AS_REP rep;
 884     KDCOptions f = b->kdc_options;
 885     hdb_entry_ex *client = NULL, *server = NULL;
 886     krb5_enctype cetype, setype, sessionetype;
 887     krb5_data e_data;
 888     EncTicketPart et;
 889     EncKDCRepPart ek;
 890     krb5_principal client_princ = NULL, server_princ = NULL;
 891     char *client_name = NULL, *server_name = NULL;
 892     krb5_error_code ret = 0;
 893     const char *e_text = NULL;
 894     krb5_crypto crypto;
 895     Key *ckey, *skey;
 896     EncryptionKey *reply_key;
 897     int flags = 0;
 898 #ifdef PKINIT
 899     pk_client_params *pkp = NULL;
 900 #endif
 901
 902     memset(&rep, 0, sizeof(rep));
 903     krb5_data_zero(&e_data);
 904
 905     if (f.canonicalize)
 906         flags |= HDB_F_CANON;
 907
 908     if(b->sname == NULL){
 909         ret = KRB5KRB_ERR_GENERIC;
 910         e_text = "No server in request";
 911     } else{
 912         ret = _krb5_principalname2krb5_principal (context,
 913                                                   &server_princ,
 914                                                   *(b->sname),
 915                                                   b->realm);
 916         if (ret == 0)
 917             ret = krb5_unparse_name(context, server_princ, &server_name);
 918     }
 919     if (ret) {
 920         kdc_log(context, config, 0,
 921                 "AS-REQ malformed server name from %s", from);
 922         goto out;
 923     }
 924     if(b->cname == NULL){
 925         ret = KRB5KRB_ERR_GENERIC;
 926         e_text = "No client in request";
 927     } else {
 928         ret = _krb5_principalname2krb5_principal (context,
 929                                                   &client_princ,
 930                                                   *(b->cname),
 931                                                   b->realm);
 932         if (ret)
 933             goto out;
 934
 935         ret = krb5_unparse_name(context, client_princ, &client_name);
 936     }
 937     if (ret) {
 938         kdc_log(context, config, 0,
 939                 "AS-REQ malformed client name from %s", from);
 940         goto out;
 941     }
 942
 943     kdc_log(context, config, 0, "AS-REQ %s from %s for %s",
 944             client_name, from, server_name);
 945
 946     /*
 947      *
 948      */
 949
 950     if (_kdc_is_anonymous(context, client_princ)) {
 951         if (!b->kdc_options.request_anonymous) {
 952             kdc_log(context, config, 0, "Anonymous ticket w/o anonymous flag");
 953             ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 954             goto out;
 955         }
 956     } else if (b->kdc_options.request_anonymous) {
 957         kdc_log(context, config, 0,
 958                 "Request for a anonymous ticket with non "
 959                 "anonymous client name: %s", client_name);
 960         ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 961         goto out;
 962     }
 963
 964     /*
 965      *
 966      */
 967
 968     ret = _kdc_db_fetch(context, config, client_princ,
 969                         HDB_F_GET_CLIENT | flags, NULL, &client);
 970     if(ret){
 971         kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name,
 972                 krb5_get_err_text(context, ret));
 973         ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 974         goto out;
 975     }
 976
 977     ret = _kdc_db_fetch(context, config, server_princ,
 978                         HDB_F_GET_SERVER|HDB_F_GET_KRBTGT,
 979                         NULL, &server);
 980     if(ret){
 981         kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name,
 982                 krb5_get_err_text(context, ret));
 983         ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
 984         goto out;
 985     }
 986
 987     memset(&et, 0, sizeof(et));
 988     memset(&ek, 0, sizeof(ek));
 989
 990     /*
 991      * Find the client key for reply encryption and pa-type salt, Pick
 992      * the client key upfront before the other keys because that is
 993      * going to affect what enctypes we are going to use in
 994      * ETYPE-INFO{,2}.
 995      */
 996
 997     ret = _kdc_find_etype(context, client, b->etype.val, b->etype.len,
 998                           &ckey, &cetype);
 999     if (ret) {
1000         kdc_log(context, config, 0,
1001                 "Client (%s) has no support for etypes", client_name);
1002         goto out;
1003     }
1004
1005     /*
1006      * Pre-auth processing
1007      */
1008
1009     if(req->padata){
1010         int i;
1011         const PA_DATA *pa;
1012         int found_pa = 0;
1013
1014         log_patypes(context, config, req->padata);
1015
1016 #ifdef PKINIT
1017         kdc_log(context, config, 5,
1018                 "Looking for PKINIT pa-data -- %s", client_name);
1019
1020         e_text = "No PKINIT PA found";
1021
1022         i = 0;
1023         pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ);
1024         if (pa == NULL) {
1025             i = 0;
1026             pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN);
1027         }
1028         if (pa) {
1029             char *client_cert = NULL;
1030
1031             ret = _kdc_pk_rd_padata(context, config, req, pa, client, &pkp);
1032             if (ret) {
1033                 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
1034                 kdc_log(context, config, 5,
1035                         "Failed to decode PKINIT PA-DATA -- %s",
1036                         client_name);
1037                 goto ts_enc;
1038             }
1039             if (ret == 0 && pkp == NULL)
1040                 goto ts_enc;
1041
1042             ret = _kdc_pk_check_client(context,
1043                                        config,
1044                                        client,
1045                                        pkp,
1046                                        &client_cert);
1047             if (ret) {
1048                 e_text = "PKINIT certificate not allowed to "
1049                     "impersonate principal";
1050                 _kdc_pk_free_client_param(context, pkp);
1051
1052                 kdc_log(context, config, 0, "%s", e_text);
1053                 pkp = NULL;
1054                 goto out;
1055             }
1056
1057             found_pa = 1;
1058             et.flags.pre_authent = 1;
1059             kdc_log(context, config, 0,
1060                     "PKINIT pre-authentication succeeded -- %s using %s",
1061                     client_name, client_cert);
1062             free(client_cert);
1063             if (pkp)
1064                 goto preauth_done;
1065         }
1066     ts_enc:
1067 #endif
1068         kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s",
1069                 client_name);
1070
1071         i = 0;
1072         e_text = "No ENC-TS found";
1073         while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){
1074             krb5_data ts_data;
1075             PA_ENC_TS_ENC p;
1076             size_t len;
1077             EncryptedData enc_data;
1078             Key *pa_key;
1079             char *str;
1080
1081             found_pa = 1;
1082
1083             if (b->kdc_options.request_anonymous) {
1084                 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
1085                 kdc_log(context, config, 0, "ENC-TS doesn't support anon");
1086                 goto out;
1087             }
1088
1089             ret = decode_EncryptedData(pa->padata_value.data,
1090                                        pa->padata_value.length,
1091                                        &enc_data,
1092                                        &len);
1093             if (ret) {
1094                 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
1095                 kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s",
1096                         client_name);
1097                 goto out;
1098             }
1099
1100             ret = hdb_enctype2key(context, &client->entry,
1101                                   enc_data.etype, &pa_key);
1102             if(ret){
1103                 char *estr;
1104                 e_text = "No key matches pa-data";
1105                 ret = KRB5KDC_ERR_ETYPE_NOSUPP;
1106                 if(krb5_enctype_to_string(context, enc_data.etype, &estr))
1107                     estr = NULL;
1108                 if(estr == NULL)
1109                     kdc_log(context, config, 5,
1110                             "No client key matching pa-data (%d) -- %s",
1111                             enc_data.etype, client_name);
1112                 else
1113                     kdc_log(context, config, 5,
1114                             "No client key matching pa-data (%s) -- %s",
1115                             estr, client_name);
1116                 free(estr);
1117
1118                 free_EncryptedData(&enc_data);
1119                 continue;
1120             }
1121
1122         try_next_key:
1123             ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto);
1124             if (ret) {
1125                 kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
1126                         krb5_get_err_text(context, ret));
1127                 free_EncryptedData(&enc_data);
1128                 continue;
1129             }
1130
1131             ret = krb5_decrypt_EncryptedData (context,
1132                                               crypto,
1133                                               KRB5_KU_PA_ENC_TIMESTAMP,
1134                                               &enc_data,
1135                                               &ts_data);
1136             krb5_crypto_destroy(context, crypto);
1137             /*
1138              * Since the user might have several keys with the same
1139              * enctype but with diffrent salting, we need to try all
1140              * the keys with the same enctype.
1141              */
1142             if(ret){
1143                 krb5_error_code ret2;
1144                 ret2 = krb5_enctype_to_string(context,
1145                                               pa_key->key.keytype, &str);
1146                 if (ret2)
1147                     str = NULL;
1148                 kdc_log(context, config, 5,
1149                         "Failed to decrypt PA-DATA -- %s "
1150                         "(enctype %s) error %s",
1151                         client_name,
1152                         str ? str : "unknown enctype",
1153                         krb5_get_err_text(context, ret));
1154                 free(str);
1155
1156                 if(hdb_next_enctype2key(context, &client->entry,
1157                                         enc_data.etype, &pa_key) == 0)
1158                     goto try_next_key;
1159                 e_text = "Failed to decrypt PA-DATA";
1160
1161                 free_EncryptedData(&enc_data);
1162                 ret = KRB5KDC_ERR_PREAUTH_FAILED;
1163                 continue;
1164             }
1165             free_EncryptedData(&enc_data);
1166             ret = decode_PA_ENC_TS_ENC(ts_data.data,
1167                                        ts_data.length,
1168                                        &p,
1169                                        &len);
1170             krb5_data_free(&ts_data);
1171             if(ret){
1172                 e_text = "Failed to decode PA-ENC-TS-ENC";
1173                 ret = KRB5KDC_ERR_PREAUTH_FAILED;
1174                 kdc_log(context, config,
1175                         5, "Failed to decode PA-ENC-TS_ENC -- %s",
1176                         client_name);
1177                 continue;
1178             }
1179             free_PA_ENC_TS_ENC(&p);
1180             if (abs(kdc_time - p.patimestamp) > context->max_skew) {
1181                 char client_time[100];
1182
1183                 krb5_format_time(context, p.patimestamp,
1184                                  client_time, sizeof(client_time), TRUE);
1185
1186                 ret = KRB5KRB_AP_ERR_SKEW;
1187                 kdc_log(context, config, 0,
1188                         "Too large time skew, "
1189                         "client time %s is out by %u > %u seconds -- %s",
1190                         client_time,
1191                         (unsigned)abs(kdc_time - p.patimestamp),
1192                         context->max_skew,
1193                         client_name);
1194 #if 0
1195                 /* This code is from samba, needs testing */
1196                 /*
1197                  * the following is needed to make windows clients
1198                  * to retry using the timestamp in the error message
1199                  *
1200                  * this is maybe a bug in windows to not trying when e_text
1201                  * is present...
1202                  */
1203                 e_text = NULL;
1204 #else
1205                 e_text = "Too large time skew";
1206 #endif
1207                 goto out;
1208             }
1209             et.flags.pre_authent = 1;
1210
1211             ret = krb5_enctype_to_string(context,pa_key->key.keytype, &str);
1212             if (ret)
1213                 str = NULL;
1214
1215             kdc_log(context, config, 2,
1216                     "ENC-TS Pre-authentication succeeded -- %s using %s",
1217                     client_name, str ? str : "unknown enctype");
1218             free(str);
1219             break;
1220         }
1221 #ifdef PKINIT
1222     preauth_done:
1223 #endif
1224         if(found_pa == 0 && config->require_preauth)
1225             goto use_pa;
1226         /* We come here if we found a pa-enc-timestamp, but if there
1227            was some problem with it, other than too large skew */
1228         if(found_pa && et.flags.pre_authent == 0){
1229             kdc_log(context, config, 0, "%s -- %s", e_text, client_name);
1230             e_text = NULL;
1231             goto out;
1232         }
1233     }else if (config->require_preauth
1234               || b->kdc_options.request_anonymous /* hack to force anon */
1235               || client->entry.flags.require_preauth
1236               || server->entry.flags.require_preauth) {
1237         METHOD_DATA method_data;
1238         PA_DATA *pa;
1239         unsigned char *buf;
1240         size_t len;
1241
1242     use_pa:
1243         method_data.len = 0;
1244         method_data.val = NULL;
1245
1246         ret = realloc_method_data(&method_data);
1247         if (ret) {
1248             free_METHOD_DATA(&method_data);
1249             goto out;
1250         }
1251         pa = &method_data.val[method_data.len-1];
1252         pa->padata_type         = KRB5_PADATA_ENC_TIMESTAMP;
1253         pa->padata_value.length = 0;
1254         pa->padata_value.data   = NULL;
1255
1256 #ifdef PKINIT
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_PK_AS_REQ;
1264         pa->padata_value.length = 0;
1265         pa->padata_value.data   = NULL;
1266
1267         ret = realloc_method_data(&method_data);
1268         if (ret) {
1269             free_METHOD_DATA(&method_data);
1270             goto out;
1271         }
1272         pa = &method_data.val[method_data.len-1];
1273         pa->padata_type         = KRB5_PADATA_PK_AS_REQ_WIN;
1274         pa->padata_value.length = 0;
1275         pa->padata_value.data   = NULL;
1276 #endif
1277
1278         /*
1279          * If there is a client key, send ETYPE_INFO{,2}
1280          */
1281         if (ckey) {
1282
1283             /*
1284              * RFC4120 requires:
1285              * - If the client only knows about old enctypes, then send
1286              *   both info replies (we send 'info' first in the list).
1287              * - If the client is 'modern', because it knows about 'new'
1288              *   enctype types, then only send the 'info2' reply.
1289              *
1290              * Before we send the full list of etype-info data, we pick
1291              * the client key we would have used anyway below, just pick
1292              * that instead.
1293              */
1294
1295             if (older_enctype(ckey->key.keytype)) {
1296                 ret = get_pa_etype_info(context, config,
1297                                         &method_data, ckey);
1298                 if (ret) {
1299                     free_METHOD_DATA(&method_data);
1300                     goto out;
1301                 }
1302             }
1303             ret = get_pa_etype_info2(context, config,
1304                                      &method_data, ckey);
1305             if (ret) {
1306                 free_METHOD_DATA(&method_data);
1307                 goto out;
1308             }
1309         }
1310
1311         ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret);
1312         free_METHOD_DATA(&method_data);
1313
1314         e_data.data   = buf;
1315         e_data.length = len;
1316         e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ",
1317
1318         ret = KRB5KDC_ERR_PREAUTH_REQUIRED;
1319
1320         kdc_log(context, config, 0,
1321                 "No preauth found, returning PREAUTH-REQUIRED -- %s",
1322                 client_name);
1323         goto out;
1324     }
1325
1326     /*
1327      * Verify flags after the user been required to prove its identity
1328      * with in a preauth mech.
1329      */
1330
1331     ret = _kdc_check_access(context, config, client, client_name,
1332                             server, server_name,
1333                             req, &e_data);
1334     if(ret)
1335         goto out;
1336
1337     /*
1338      * Selelct the best encryption type for the KDC with out regard to
1339      * the client since the client never needs to read that data.
1340      */
1341
1342     ret = _kdc_get_preferred_key(context, config,
1343                                  server, server_name,
1344                                  &setype, &skey);
1345     if(ret)
1346         goto out;
1347
1348     /*
1349      * Select a session enctype from the list of the crypto systems
1350      * supported enctype, is supported by the client and is one of the
1351      * enctype of the enctype of the krbtgt.
1352      *
1353      * The later is used as a hint what enctype all KDC are supporting
1354      * to make sure a newer version of KDC wont generate a session
1355      * enctype that and older version of a KDC in the same realm can't
1356      * decrypt.
1357      *
1358      * But if the KDC admin is paranoid and doesn't want to have "no
1359      * the best" enctypes on the krbtgt, lets save the best pick from
1360      * the client list and hope that that will work for any other
1361      * KDCs.
1362      */
1363     {
1364         const krb5_enctype *p;
1365         krb5_enctype clientbest = ETYPE_NULL;
1366         int i, j;
1367
1368         p = krb5_kerberos_enctypes(context);
1369
1370         sessionetype = ETYPE_NULL;
1371
1372         for (i = 0; p[i] != ETYPE_NULL && sessionetype == ETYPE_NULL; i++) {
1373             if (krb5_enctype_valid(context, p[i]) != 0)
1374                 continue;
1375
1376             for (j = 0; j < b->etype.len && sessionetype == ETYPE_NULL; j++) {
1377                 Key *dummy;
1378                 /* check with client */
1379                 if (p[i] != b->etype.val[j])
1380                     continue;
1381                 /* save best of union of { client, crypto system } */
1382                 if (clientbest == ETYPE_NULL)
1383                     clientbest = p[i];
1384                 /* check with krbtgt */
1385                 ret = hdb_enctype2key(context, &server->entry, p[i], &dummy);
1386                 if (ret)
1387                     continue;
1388                 sessionetype = p[i];
1389             }
1390         }
1391         /* if krbtgt had no shared keys with client, pick clients best */
1392         if (clientbest != ETYPE_NULL && sessionetype == ETYPE_NULL) {
1393             sessionetype = clientbest;
1394         } else if (sessionetype == ETYPE_NULL) {
1395             kdc_log(context, config, 0,
1396                     "Client (%s) from %s has no common enctypes with KDC"
1397                     "to use for the session key",
1398                     client_name, from);
1399             goto out;
1400         }
1401     }
1402
1403     log_as_req(context, config, cetype, setype, b);
1404
1405     if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey
1406        || (f.request_anonymous && !config->allow_anonymous)) {
1407         ret = KRB5KDC_ERR_BADOPTION;
1408         kdc_log(context, config, 0, "Bad KDC options -- %s", client_name);
1409         goto out;
1410     }
1411
1412     rep.pvno = 5;
1413     rep.msg_type = krb_as_rep;
1414
1415     ret = copy_Realm(&client->entry.principal->realm, &rep.crealm);
1416     if (ret)
1417         goto out;
1418     ret = _krb5_principal2principalname(&rep.cname, client->entry.principal);
1419     if (ret)
1420         goto out;
1421
1422     rep.ticket.tkt_vno = 5;
1423     copy_Realm(&server->entry.principal->realm, &rep.ticket.realm);
1424     _krb5_principal2principalname(&rep.ticket.sname,
1425                                   server->entry.principal);
1426     /* java 1.6 expects the name to be the same type, lets allow that
1427      * uncomplicated name-types. */
1428 #define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t)
1429     if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST))
1430         rep.ticket.sname.name_type = b->sname->name_type;
1431 #undef CNT
1432
1433     et.flags.initial = 1;
1434     if(client->entry.flags.forwardable && server->entry.flags.forwardable)
1435         et.flags.forwardable = f.forwardable;
1436     else if (f.forwardable) {
1437         ret = KRB5KDC_ERR_POLICY;
1438         kdc_log(context, config, 0,
1439                 "Ticket may not be forwardable -- %s", client_name);
1440         goto out;
1441     }
1442     if(client->entry.flags.proxiable && server->entry.flags.proxiable)
1443         et.flags.proxiable = f.proxiable;
1444     else if (f.proxiable) {
1445         ret = KRB5KDC_ERR_POLICY;
1446         kdc_log(context, config, 0,
1447                 "Ticket may not be proxiable -- %s", client_name);
1448         goto out;
1449     }
1450     if(client->entry.flags.postdate && server->entry.flags.postdate)
1451         et.flags.may_postdate = f.allow_postdate;
1452     else if (f.allow_postdate){
1453         ret = KRB5KDC_ERR_POLICY;
1454         kdc_log(context, config, 0,
1455                 "Ticket may not be postdatable -- %s", client_name);
1456         goto out;
1457     }
1458
1459     /* check for valid set of addresses */
1460     if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) {
1461         ret = KRB5KRB_AP_ERR_BADADDR;
1462         kdc_log(context, config, 0,
1463                 "Bad address list requested -- %s", client_name);
1464         goto out;
1465     }
1466
1467     ret = copy_PrincipalName(&rep.cname, &et.cname);
1468     if (ret)
1469         goto out;
1470     ret = copy_Realm(&rep.crealm, &et.crealm);
1471     if (ret)
1472         goto out;
1473
1474     {
1475         time_t start;
1476         time_t t;
1477
1478         start = et.authtime = kdc_time;
1479
1480         if(f.postdated && req->req_body.from){
1481             ALLOC(et.starttime);
1482             start = *et.starttime = *req->req_body.from;
1483             et.flags.invalid = 1;
1484             et.flags.postdated = 1; /* XXX ??? */
1485         }
1486         _kdc_fix_time(&b->till);
1487         t = *b->till;
1488
1489         /* be careful not overflowing */
1490
1491         if(client->entry.max_life)
1492             t = start + min(t - start, *client->entry.max_life);
1493         if(server->entry.max_life)
1494             t = start + min(t - start, *server->entry.max_life);
1495 #if 0
1496         t = min(t, start + realm->max_life);
1497 #endif
1498         et.endtime = t;
1499         if(f.renewable_ok && et.endtime < *b->till){
1500             f.renewable = 1;
1501             if(b->rtime == NULL){
1502                 ALLOC(b->rtime);
1503                 *b->rtime = 0;
1504             }
1505             if(*b->rtime < *b->till)
1506                 *b->rtime = *b->till;
1507         }
1508         if(f.renewable && b->rtime){
1509             t = *b->rtime;
1510             if(t == 0)
1511                 t = MAX_TIME;
1512             if(client->entry.max_renew)
1513                 t = start + min(t - start, *client->entry.max_renew);
1514             if(server->entry.max_renew)
1515                 t = start + min(t - start, *server->entry.max_renew);
1516 #if 0
1517             t = min(t, start + realm->max_renew);
1518 #endif
1519             ALLOC(et.renew_till);
1520             *et.renew_till = t;
1521             et.flags.renewable = 1;
1522         }
1523     }
1524
1525     if (f.request_anonymous)
1526         et.flags.anonymous = 1;
1527
1528     if(b->addresses){
1529         ALLOC(et.caddr);
1530         copy_HostAddresses(b->addresses, et.caddr);
1531     }
1532
1533     et.transited.tr_type = DOMAIN_X500_COMPRESS;
1534     krb5_data_zero(&et.transited.contents);
1535
1536     /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded
1537      * as 0 and as 0x80 (meaning indefinite length) apart, and is thus
1538      * incapable of correctly decoding SEQUENCE OF's of zero length.
1539      *
1540      * To fix this, always send at least one no-op last_req
1541      *
1542      * If there's a pw_end or valid_end we will use that,
1543      * otherwise just a dummy lr.
1544      */
1545     ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val));
1546     if (ek.last_req.val == NULL) {
1547         ret = ENOMEM;
1548         goto out;
1549     }
1550     ek.last_req.len = 0;
1551     if (client->entry.pw_end
1552         && (config->kdc_warn_pwexpire == 0
1553             || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) {
1554         ek.last_req.val[ek.last_req.len].lr_type  = LR_PW_EXPTIME;
1555         ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end;
1556         ++ek.last_req.len;
1557     }
1558     if (client->entry.valid_end) {
1559         ek.last_req.val[ek.last_req.len].lr_type  = LR_ACCT_EXPTIME;
1560         ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end;
1561         ++ek.last_req.len;
1562     }
1563     if (ek.last_req.len == 0) {
1564         ek.last_req.val[ek.last_req.len].lr_type  = LR_NONE;
1565         ek.last_req.val[ek.last_req.len].lr_value = 0;
1566         ++ek.last_req.len;
1567     }
1568     ek.nonce = b->nonce;
1569     if (client->entry.valid_end || client->entry.pw_end) {
1570         ALLOC(ek.key_expiration);
1571         if (client->entry.valid_end) {
1572             if (client->entry.pw_end)
1573                 *ek.key_expiration = min(*client->entry.valid_end,
1574                                          *client->entry.pw_end);
1575             else
1576                 *ek.key_expiration = *client->entry.valid_end;
1577         } else
1578             *ek.key_expiration = *client->entry.pw_end;
1579     } else
1580         ek.key_expiration = NULL;
1581     ek.flags = et.flags;
1582     ek.authtime = et.authtime;
1583     if (et.starttime) {
1584         ALLOC(ek.starttime);
1585         *ek.starttime = *et.starttime;
1586     }
1587     ek.endtime = et.endtime;
1588     if (et.renew_till) {
1589         ALLOC(ek.renew_till);
1590         *ek.renew_till = *et.renew_till;
1591     }
1592     copy_Realm(&rep.ticket.realm, &ek.srealm);
1593     copy_PrincipalName(&rep.ticket.sname, &ek.sname);
1594     if(et.caddr){
1595         ALLOC(ek.caddr);
1596         copy_HostAddresses(et.caddr, ek.caddr);
1597     }
1598
1599     ALLOC(rep.padata);
1600     rep.padata->len = 0;
1601     rep.padata->val = NULL;
1602
1603 #if PKINIT
1604     if (pkp) {
1605         e_text = "Failed to build PK-INIT reply";
1606         ret = _kdc_pk_mk_pa_reply(context, config, pkp, client,
1607                                   sessionetype, req, req_buffer,
1608                                   &reply_key, &et.key, rep.padata);
1609         if (ret)
1610             goto out;
1611         ret = _kdc_add_inital_verified_cas(context,
1612                                            config,
1613                                            pkp,
1614                                            &et);
1615         if (ret)
1616             goto out;
1617     } else
1618 #endif
1619     if (ckey) {
1620         reply_key = &ckey->key;
1621         ret = krb5_generate_random_keyblock(context, sessionetype, &et.key);
1622         if (ret)
1623             goto out;
1624     } else {
1625         e_text = "Client have no reply key";
1626         ret = KRB5KDC_ERR_CLIENT_NOTYET;
1627         goto out;
1628     }
1629
1630     ret = copy_EncryptionKey(&et.key, &ek.key);
1631     if (ret)
1632         goto out;
1633
1634     if (ckey)
1635         set_salt_padata (rep.padata, ckey->salt);
1636
1637     /* Add signing of alias referral */
1638     if (f.canonicalize) {
1639         PA_ClientCanonicalized canon;
1640         krb5_data data;
1641         PA_DATA pa;
1642         krb5_crypto crypto;
1643         size_t len;
1644
1645         memset(&canon, 0, sizeof(canon));
1646
1647         canon.names.requested_name = *b->cname;
1648         canon.names.mapped_name = client->entry.principal->name;
1649
1650         ASN1_MALLOC_ENCODE(PA_ClientCanonicalizedNames, data.data, data.length,
1651                            &canon.names, &len, ret);
1652         if (ret)
1653             goto out;
1654         if (data.length != len)
1655             krb5_abortx(context, "internal asn.1 error");
1656
1657         /* sign using "returned session key" */
1658         ret = krb5_crypto_init(context, &et.key, 0, &crypto);
1659         if (ret) {
1660             free(data.data);
1661             goto out;
1662         }
1663
1664         ret = krb5_create_checksum(context, crypto,
1665                                    KRB5_KU_CANONICALIZED_NAMES, 0,
1666                                    data.data, data.length,
1667                                    &canon.canon_checksum);
1668         free(data.data);
1669         krb5_crypto_destroy(context, crypto);
1670         if (ret)
1671             goto out;
1672
1673         ASN1_MALLOC_ENCODE(PA_ClientCanonicalized, data.data, data.length,
1674                            &canon, &len, ret);
1675         free_Checksum(&canon.canon_checksum);
1676         if (ret)
1677             goto out;
1678         if (data.length != len)
1679             krb5_abortx(context, "internal asn.1 error");
1680
1681         pa.padata_type = KRB5_PADATA_CLIENT_CANONICALIZED;
1682         pa.padata_value = data;
1683         ret = add_METHOD_DATA(rep.padata, &pa);
1684         free(data.data);
1685         if (ret)
1686             goto out;
1687     }
1688
1689     if (rep.padata->len == 0) {
1690         free(rep.padata);
1691         rep.padata = NULL;
1692     }
1693
1694     /* Add the PAC */
1695     if (send_pac_p(context, req)) {
1696         krb5_pac p = NULL;
1697         krb5_data data;
1698
1699         ret = _kdc_pac_generate(context, client, &p);
1700         if (ret) {
1701             kdc_log(context, config, 0, "PAC generation failed for -- %s",
1702                     client_name);
1703             goto out;
1704         }
1705         if (p != NULL) {
1706             ret = _krb5_pac_sign(context, p, et.authtime,
1707                                  client->entry.principal,
1708                                  &skey->key, /* Server key */
1709                                  &skey->key, /* FIXME: should be krbtgt key */
1710                                  &data);
1711             krb5_pac_free(context, p);
1712             if (ret) {
1713                 kdc_log(context, config, 0, "PAC signing failed for -- %s",
1714                         client_name);
1715                 goto out;
1716             }
1717
1718             ret = _kdc_tkt_add_if_relevant_ad(context, &et,
1719                                               KRB5_AUTHDATA_WIN2K_PAC,
1720                                               &data);
1721             krb5_data_free(&data);
1722             if (ret)
1723                 goto out;
1724         }
1725     }
1726
1727     _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime,
1728                        et.endtime, et.renew_till);
1729
1730     /* do this as the last thing since this signs the EncTicketPart */
1731     ret = _kdc_add_KRB5SignedPath(context,
1732                                   config,
1733                                   server,
1734                                   setype,
1735                                   NULL,
1736                                   NULL,
1737                                   &et);
1738     if (ret)
1739         goto out;
1740
1741     ret = _kdc_encode_reply(context, config,
1742                             &rep, &et, &ek, setype, server->entry.kvno,
1743                             &skey->key, client->entry.kvno,
1744                             reply_key, &e_text, reply);
1745     free_EncTicketPart(&et);
1746     free_EncKDCRepPart(&ek);
1747     if (ret)
1748         goto out;
1749
1750     /* */
1751     if (datagram_reply && reply->length > config->max_datagram_reply_length) {
1752         krb5_data_free(reply);
1753         ret = KRB5KRB_ERR_RESPONSE_TOO_BIG;
1754         e_text = "Reply packet too large";
1755     }
1756
1757 out:
1758     free_AS_REP(&rep);
1759     if(ret){
1760         krb5_mk_error(context,
1761                       ret,
1762                       e_text,
1763                       (e_data.data ? &e_data : NULL),
1764                       client_princ,
1765                       server_princ,
1766                       NULL,
1767                       NULL,
1768                       reply);
1769         ret = 0;
1770     }
1771 #ifdef PKINIT
1772     if (pkp)
1773         _kdc_pk_free_client_param(context, pkp);
1774 #endif
1775     if (e_data.data)
1776         free(e_data.data);
1777     if (client_princ)
1778         krb5_free_principal(context, client_princ);
1779     free(client_name);
1780     if (server_princ)
1781         krb5_free_principal(context, server_princ);
1782     free(server_name);
1783     if(client)
1784         _kdc_free_ent(context, client);
1785     if(server)
1786         _kdc_free_ent(context, server);
1787     return ret;
1788 }
1789
1790 /*
1791  * Add the AuthorizationData `data´ of `type´ to the last element in
1792  * the sequence of authorization_data in `tkt´ wrapped in an IF_RELEVANT
1793  */
1794
1795 krb5_error_code
1796 _kdc_tkt_add_if_relevant_ad(krb5_context context,
1797                             EncTicketPart *tkt,
1798                             int type,
1799                             const krb5_data *data)
1800 {
1801     krb5_error_code ret;
1802     size_t size;
1803
1804     if (tkt->authorization_data == NULL) {
1805         tkt->authorization_data = calloc(1, sizeof(*tkt->authorization_data));
1806         if (tkt->authorization_data == NULL) {
1807             krb5_set_error_message(context, ENOMEM, "out of memory");
1808             return ENOMEM;
1809         }
1810     }
1811
1812     /* add the entry to the last element */
1813     {
1814         AuthorizationData ad = { 0, NULL };
1815         AuthorizationDataElement ade;
1816
1817         ade.ad_type = type;
1818         ade.ad_data = *data;
1819
1820         ret = add_AuthorizationData(&ad, &ade);
1821         if (ret) {
1822             krb5_set_error_message(context, ret, "add AuthorizationData failed");
1823             return ret;
1824         }
1825
1826         ade.ad_type = KRB5_AUTHDATA_IF_RELEVANT;
1827
1828         ASN1_MALLOC_ENCODE(AuthorizationData,
1829                            ade.ad_data.data, ade.ad_data.length,
1830                            &ad, &size, ret);
1831         free_AuthorizationData(&ad);
1832         if (ret) {
1833             krb5_set_error_message(context, ret, "ASN.1 encode of "
1834                                    "AuthorizationData failed");
1835             return ret;
1836         }
1837         if (ade.ad_data.length != size)
1838             krb5_abortx(context, "internal asn.1 encoder error");
1839
1840         ret = add_AuthorizationData(tkt->authorization_data, &ade);
1841         der_free_octet_string(&ade.ad_data);
1842         if (ret) {
1843             krb5_set_error_message(context, ret, "add AuthorizationData failed");
1844             return ret;
1845         }
1846     }
1847
1848     return 0;
1849 }