lib/krb5/get_in_tkt.c

   1 /*
   2  * Copyright (c) 1997 - 2008 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 #define KRB5_DEPRECATED_FUNCTION(x)
  35
  36 #include "krb5_locl.h"
  37
  38 #ifndef HEIMDAL_SMALLER
  39
  40 static krb5_error_code
  41 make_pa_enc_timestamp(krb5_context context, PA_DATA *pa,
  42                       krb5_enctype etype, krb5_keyblock *key)
  43 {
  44     PA_ENC_TS_ENC p;
  45     unsigned char *buf;
  46     size_t buf_size;
  47     size_t len = 0;
  48     EncryptedData encdata;
  49     krb5_error_code ret;
  50     int32_t usec;
  51     int usec2;
  52     krb5_crypto crypto;
  53
  54     krb5_us_timeofday (context, &p.patimestamp, &usec);
  55     usec2         = usec;
  56     p.pausec      = &usec2;
  57
  58     ASN1_MALLOC_ENCODE(PA_ENC_TS_ENC, buf, buf_size, &p, &len, ret);
  59     if (ret)
  60         return ret;
  61     if(buf_size != len)
  62         krb5_abortx(context, "internal error in ASN.1 encoder");
  63     ret = krb5_crypto_init(context, key, 0, &crypto);
  64     if (ret) {
  65         free(buf);
  66         return ret;
  67     }
  68     ret = krb5_encrypt_EncryptedData(context,
  69                                      crypto,
  70                                      KRB5_KU_PA_ENC_TIMESTAMP,
  71                                      buf,
  72                                      len,
  73                                      0,
  74                                      &encdata);
  75     free(buf);
  76     krb5_crypto_destroy(context, crypto);
  77     if (ret)
  78         return ret;
  79
  80     ASN1_MALLOC_ENCODE(EncryptedData, buf, buf_size, &encdata, &len, ret);
  81     free_EncryptedData(&encdata);
  82     if (ret)
  83         return ret;
  84     if(buf_size != len)
  85         krb5_abortx(context, "internal error in ASN.1 encoder");
  86     pa->padata_type = KRB5_PADATA_ENC_TIMESTAMP;
  87     pa->padata_value.length = len;
  88     pa->padata_value.data = buf;
  89     return 0;
  90 }
  91
  92 static krb5_error_code
  93 add_padata(krb5_context context,
  94            METHOD_DATA *md,
  95            krb5_principal client,
  96            krb5_key_proc key_proc,
  97            krb5_const_pointer keyseed,
  98            krb5_enctype *enctypes,
  99            unsigned netypes,
 100            krb5_salt *salt)
 101 {
 102     krb5_error_code ret;
 103     PA_DATA *pa2;
 104     krb5_salt salt2;
 105     krb5_enctype *ep;
 106     size_t i;
 107
 108     if(salt == NULL) {
 109         /* default to standard salt */
 110         ret = krb5_get_pw_salt (context, client, &salt2);
 111         if (ret)
 112             return ret;
 113         salt = &salt2;
 114     }
 115     if (!enctypes) {
 116         enctypes = context->etypes;
 117         netypes = 0;
 118         for (ep = enctypes; *ep != ETYPE_NULL; ep++)
 119             netypes++;
 120     }
 121     pa2 = realloc (md->val, (md->len + netypes) * sizeof(*md->val));
 122     if (pa2 == NULL)
 123         return krb5_enomem(context);
 124     md->val = pa2;
 125
 126     for (i = 0; i < netypes; ++i) {
 127         krb5_keyblock *key;
 128
 129         ret = (*key_proc)(context, enctypes[i], *salt, keyseed, &key);
 130         if (ret)
 131             continue;
 132         ret = make_pa_enc_timestamp (context, &md->val[md->len],
 133                                      enctypes[i], key);
 134         krb5_free_keyblock (context, key);
 135         if (ret)
 136             return ret;
 137         ++md->len;
 138     }
 139     if(salt == &salt2)
 140         krb5_free_salt(context, salt2);
 141     return 0;
 142 }
 143
 144 static krb5_error_code
 145 init_as_req (krb5_context context,
 146              KDCOptions opts,
 147              krb5_creds *creds,
 148              const krb5_addresses *addrs,
 149              const krb5_enctype *etypes,
 150              const krb5_preauthtype *ptypes,
 151              const krb5_preauthdata *preauth,
 152              krb5_key_proc key_proc,
 153              krb5_const_pointer keyseed,
 154              unsigned nonce,
 155              AS_REQ *a)
 156 {
 157     krb5_error_code ret;
 158     krb5_salt salt;
 159
 160     memset(a, 0, sizeof(*a));
 161
 162     a->pvno = 5;
 163     a->msg_type = krb_as_req;
 164     a->req_body.kdc_options = opts;
 165     a->req_body.cname = malloc(sizeof(*a->req_body.cname));
 166     if (a->req_body.cname == NULL) {
 167         ret = krb5_enomem(context);
 168         goto fail;
 169     }
 170     a->req_body.sname = malloc(sizeof(*a->req_body.sname));
 171     if (a->req_body.sname == NULL) {
 172         ret = krb5_enomem(context);
 173         goto fail;
 174     }
 175     ret = _krb5_principal2principalname (a->req_body.cname, creds->client);
 176     if (ret)
 177         goto fail;
 178     ret = _krb5_principal2principalname (a->req_body.sname, creds->server);
 179     if (ret)
 180         goto fail;
 181     ret = copy_Realm(&creds->client->realm, &a->req_body.realm);
 182     if (ret)
 183         goto fail;
 184
 185     if(creds->times.starttime) {
 186         a->req_body.from = malloc(sizeof(*a->req_body.from));
 187         if (a->req_body.from == NULL) {
 188             ret = krb5_enomem(context);
 189             goto fail;
 190         }
 191         *a->req_body.from = creds->times.starttime;
 192     }
 193     if(creds->times.endtime){
 194         ALLOC(a->req_body.till, 1);
 195         *a->req_body.till = creds->times.endtime;
 196     }
 197     if(creds->times.renew_till){
 198         a->req_body.rtime = malloc(sizeof(*a->req_body.rtime));
 199         if (a->req_body.rtime == NULL) {
 200             ret = krb5_enomem(context);
 201             goto fail;
 202         }
 203         *a->req_body.rtime = creds->times.renew_till;
 204     }
 205     a->req_body.nonce = nonce;
 206     ret = _krb5_init_etype(context,
 207                            KRB5_PDU_AS_REQUEST,
 208                            &a->req_body.etype.len,
 209                            &a->req_body.etype.val,
 210                            etypes);
 211     if (ret)
 212         goto fail;
 213
 214     /*
 215      * This means no addresses
 216      */
 217
 218     if (addrs && addrs->len == 0) {
 219         a->req_body.addresses = NULL;
 220     } else {
 221         a->req_body.addresses = malloc(sizeof(*a->req_body.addresses));
 222         if (a->req_body.addresses == NULL) {
 223             ret = krb5_enomem(context);
 224             goto fail;
 225         }
 226
 227         if (addrs)
 228             ret = krb5_copy_addresses(context, addrs, a->req_body.addresses);
 229         else {
 230             ret = krb5_get_all_client_addrs (context, a->req_body.addresses);
 231             if(ret == 0 && a->req_body.addresses->len == 0) {
 232                 free(a->req_body.addresses);
 233                 a->req_body.addresses = NULL;
 234             }
 235         }
 236         if (ret)
 237             return ret;
 238     }
 239
 240     a->req_body.enc_authorization_data = NULL;
 241     a->req_body.additional_tickets = NULL;
 242
 243     if(preauth != NULL) {
 244         size_t i;
 245         ALLOC(a->padata, 1);
 246         if(a->padata == NULL) {
 247             ret = krb5_enomem(context);
 248             goto fail;
 249         }
 250         a->padata->val = NULL;
 251         a->padata->len = 0;
 252         for(i = 0; i < preauth->len; i++) {
 253             if(preauth->val[i].type == KRB5_PADATA_ENC_TIMESTAMP){
 254                 size_t j;
 255
 256                 for(j = 0; j < preauth->val[i].info.len; j++) {
 257                     krb5_salt *sp = &salt;
 258                     if(preauth->val[i].info.val[j].salttype)
 259                         salt.salttype = *preauth->val[i].info.val[j].salttype;
 260                     else
 261                         salt.salttype = KRB5_PW_SALT;
 262                     if(preauth->val[i].info.val[j].salt)
 263                         salt.saltvalue = *preauth->val[i].info.val[j].salt;
 264                     else
 265                         if(salt.salttype == KRB5_PW_SALT)
 266                             sp = NULL;
 267                         else
 268                             krb5_data_zero(&salt.saltvalue);
 269                     ret = add_padata(context, a->padata, creds->client,
 270                                      key_proc, keyseed,
 271                                      &preauth->val[i].info.val[j].etype, 1,
 272                                      sp);
 273                     if (ret == 0)
 274                         break;
 275                 }
 276             }
 277         }
 278     } else
 279     /* not sure this is the way to use `ptypes' */
 280     if (ptypes == NULL || *ptypes == KRB5_PADATA_NONE)
 281         a->padata = NULL;
 282     else if (*ptypes ==  KRB5_PADATA_ENC_TIMESTAMP) {
 283         ALLOC(a->padata, 1);
 284         if (a->padata == NULL) {
 285             ret = krb5_enomem(context);
 286             goto fail;
 287         }
 288         a->padata->len = 0;
 289         a->padata->val = NULL;
 290
 291         /* make a v5 salted pa-data */
 292         add_padata(context, a->padata, creds->client,
 293                    key_proc, keyseed, a->req_body.etype.val,
 294                    a->req_body.etype.len, NULL);
 295
 296         /* make a v4 salted pa-data */
 297         salt.salttype = KRB5_PW_SALT;
 298         krb5_data_zero(&salt.saltvalue);
 299         add_padata(context, a->padata, creds->client,
 300                    key_proc, keyseed, a->req_body.etype.val,
 301                    a->req_body.etype.len, &salt);
 302     } else {
 303         ret = KRB5_PREAUTH_BAD_TYPE;
 304         krb5_set_error_message (context, ret,
 305                                 N_("pre-auth type %d not supported", ""),
 306                                *ptypes);
 307         goto fail;
 308     }
 309     return 0;
 310 fail:
 311     free_AS_REQ(a);
 312     return ret;
 313 }
 314
 315 static int
 316 set_ptypes(krb5_context context,
 317            KRB_ERROR *error,
 318            const krb5_preauthtype **ptypes,
 319            krb5_preauthdata **preauth)
 320 {
 321     static krb5_preauthdata preauth2;
 322     static const krb5_preauthtype ptypes2[] = {
 323             KRB5_PADATA_ENC_TIMESTAMP, KRB5_PADATA_NONE
 324     };
 325
 326     if(error->e_data) {
 327         METHOD_DATA md;
 328         size_t i;
 329         decode_METHOD_DATA(error->e_data->data,
 330                            error->e_data->length,
 331                            &md,
 332                            NULL);
 333         for(i = 0; i < md.len; i++){
 334             switch(md.val[i].padata_type){
 335             case KRB5_PADATA_ENC_TIMESTAMP:
 336                 *ptypes = ptypes2;
 337                 break;
 338             case KRB5_PADATA_ETYPE_INFO:
 339                 *preauth = &preauth2;
 340                 ALLOC_SEQ(*preauth, 1);
 341                 (*preauth)->val[0].type = KRB5_PADATA_ENC_TIMESTAMP;
 342                 decode_ETYPE_INFO(md.val[i].padata_value.data,
 343                                   md.val[i].padata_value.length,
 344                                   &(*preauth)->val[0].info,
 345                                   NULL);
 346                 break;
 347             default:
 348                 break;
 349             }
 350         }
 351         free_METHOD_DATA(&md);
 352     } else {
 353         *ptypes = ptypes2;
 354     }
 355     return(1);
 356 }
 357
 358 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 359 krb5_get_in_cred(krb5_context context,
 360                  krb5_flags options,
 361                  const krb5_addresses *addrs,
 362                  const krb5_enctype *etypes,
 363                  const krb5_preauthtype *ptypes,
 364                  const krb5_preauthdata *preauth,
 365                  krb5_key_proc key_proc,
 366                  krb5_const_pointer keyseed,
 367                  krb5_decrypt_proc decrypt_proc,
 368                  krb5_const_pointer decryptarg,
 369                  krb5_creds *creds,
 370                  krb5_kdc_rep *ret_as_reply)
 371     KRB5_DEPRECATED_FUNCTION("Use X instead")
 372 {
 373     krb5_error_code ret;
 374     AS_REQ a;
 375     krb5_kdc_rep rep;
 376     krb5_data req, resp;
 377     size_t len = 0;
 378     krb5_salt salt;
 379     krb5_keyblock *key;
 380     size_t size;
 381     KDCOptions opts;
 382     PA_DATA *pa;
 383     krb5_enctype etype;
 384     krb5_preauthdata *my_preauth = NULL;
 385     unsigned nonce;
 386     int done;
 387
 388     opts = int2KDCOptions(options);
 389
 390     krb5_generate_random_block (&nonce, sizeof(nonce));
 391     nonce &= 0xffffffff;
 392
 393     do {
 394         done = 1;
 395         ret = init_as_req (context,
 396                            opts,
 397                            creds,
 398                            addrs,
 399                            etypes,
 400                            ptypes,
 401                            preauth,
 402                            key_proc,
 403                            keyseed,
 404                            nonce,
 405                            &a);
 406         if (my_preauth) {
 407             free_ETYPE_INFO(&my_preauth->val[0].info);
 408             free (my_preauth->val);
 409             my_preauth = NULL;
 410         }
 411         if (ret)
 412             return ret;
 413
 414         ASN1_MALLOC_ENCODE(AS_REQ, req.data, req.length, &a, &len, ret);
 415         free_AS_REQ(&a);
 416         if (ret)
 417             return ret;
 418         if(len != req.length)
 419             krb5_abortx(context, "internal error in ASN.1 encoder");
 420
 421         ret = krb5_sendto_kdc (context, &req, &creds->client->realm, &resp);
 422         krb5_data_free(&req);
 423         if (ret)
 424             return ret;
 425
 426         memset (&rep, 0, sizeof(rep));
 427         ret = decode_AS_REP(resp.data, resp.length, &rep.kdc_rep, &size);
 428         if(ret) {
 429             /* let's try to parse it as a KRB-ERROR */
 430             KRB_ERROR error;
 431             int ret2;
 432
 433             ret2 = krb5_rd_error(context, &resp, &error);
 434             if(ret2 && resp.data && ((char*)resp.data)[0] == 4)
 435                 ret = KRB5KRB_AP_ERR_V4_REPLY;
 436             krb5_data_free(&resp);
 437             if (ret2 == 0) {
 438                 ret = krb5_error_from_rd_error(context, &error, creds);
 439                 /* if no preauth was set and KDC requires it, give it
 440                    one more try */
 441                 if (!ptypes && !preauth
 442                     && ret == KRB5KDC_ERR_PREAUTH_REQUIRED
 443                     && set_ptypes(context, &error, &ptypes, &my_preauth)) {
 444                     done = 0;
 445                     preauth = my_preauth;
 446                     krb5_free_error_contents(context, &error);
 447                     krb5_clear_error_message(context);
 448                     continue;
 449                 }
 450                 if(ret_as_reply)
 451                     ret_as_reply->error = error;
 452                 else
 453                     free_KRB_ERROR (&error);
 454                 return ret;
 455             }
 456             return ret;
 457         }
 458         krb5_data_free(&resp);
 459     } while(!done);
 460
 461     pa = NULL;
 462     etype = rep.kdc_rep.enc_part.etype;
 463     if(rep.kdc_rep.padata){
 464         int i = 0;
 465         pa = krb5_find_padata(rep.kdc_rep.padata->val, rep.kdc_rep.padata->len,
 466                               KRB5_PADATA_PW_SALT, &i);
 467         if(pa == NULL) {
 468             i = 0;
 469             pa = krb5_find_padata(rep.kdc_rep.padata->val,
 470                                   rep.kdc_rep.padata->len,
 471                                   KRB5_PADATA_AFS3_SALT, &i);
 472         }
 473     }
 474     if(pa) {
 475         salt.salttype = (krb5_salttype)pa->padata_type;
 476         salt.saltvalue = pa->padata_value;
 477
 478         ret = (*key_proc)(context, etype, salt, keyseed, &key);
 479     } else {
 480         /* make a v5 salted pa-data */
 481         ret = krb5_get_pw_salt (context, creds->client, &salt);
 482
 483         if (ret)
 484             goto out;
 485         ret = (*key_proc)(context, etype, salt, keyseed, &key);
 486         krb5_free_salt(context, salt);
 487     }
 488     if (ret)
 489         goto out;
 490
 491     {
 492         unsigned flags = EXTRACT_TICKET_TIMESYNC;
 493         if (opts.request_anonymous)
 494             flags |= EXTRACT_TICKET_ALLOW_SERVER_MISMATCH | EXTRACT_TICKET_MATCH_ANON;
 495
 496         ret = _krb5_extract_ticket(context,
 497                                    &rep,
 498                                    creds,
 499                                    key,
 500                                    keyseed,
 501                                    KRB5_KU_AS_REP_ENC_PART,
 502                                    NULL,
 503                                    nonce,
 504                                    flags,
 505                                    NULL,
 506                                    decrypt_proc,
 507                                    decryptarg);
 508     }
 509     memset (key->keyvalue.data, 0, key->keyvalue.length);
 510     krb5_free_keyblock_contents (context, key);
 511     free (key);
 512
 513 out:
 514     if (ret == 0 && ret_as_reply)
 515         *ret_as_reply = rep;
 516     else
 517         krb5_free_kdc_rep (context, &rep);
 518     return ret;
 519 }
 520
 521 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 522 krb5_get_in_tkt(krb5_context context,
 523                 krb5_flags options,
 524                 const krb5_addresses *addrs,
 525                 const krb5_enctype *etypes,
 526                 const krb5_preauthtype *ptypes,
 527                 krb5_key_proc key_proc,
 528                 krb5_const_pointer keyseed,
 529                 krb5_decrypt_proc decrypt_proc,
 530                 krb5_const_pointer decryptarg,
 531                 krb5_creds *creds,
 532                 krb5_ccache ccache,
 533                 krb5_kdc_rep *ret_as_reply)
 534     KRB5_DEPRECATED_FUNCTION("Use X instead")
 535 {
 536     krb5_error_code ret;
 537
 538     ret = krb5_get_in_cred (context,
 539                             options,
 540                             addrs,
 541                             etypes,
 542                             ptypes,
 543                             NULL,
 544                             key_proc,
 545                             keyseed,
 546                             decrypt_proc,
 547                             decryptarg,
 548                             creds,
 549                             ret_as_reply);
 550     if(ret)
 551         return ret;
 552     if (ccache)
 553         ret = krb5_cc_store_cred (context, ccache, creds);
 554     return ret;
 555 }
 556
 557 #endif /* HEIMDAL_SMALLER */