source3/libads/krb5_setpw.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    krb5 set password implementation
   4    Copyright (C) Andrew Tridgell 2001
   5    Copyright (C) Remus Koos 2001 (remuskoos@yahoo.com)
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 #ifdef HAVE_KRB5
  25
  26 #define DEFAULT_KPASSWD_PORT    464
  27
  28 #define KRB5_KPASSWD_VERS_CHANGEPW              1
  29
  30 #define KRB5_KPASSWD_VERS_SETPW                 0xff80
  31 #define KRB5_KPASSWD_VERS_SETPW_ALT             2
  32
  33 #define KRB5_KPASSWD_SUCCESS                    0
  34 #define KRB5_KPASSWD_MALFORMED                  1
  35 #define KRB5_KPASSWD_HARDERROR                  2
  36 #define KRB5_KPASSWD_AUTHERROR                  3
  37 #define KRB5_KPASSWD_SOFTERROR                  4
  38 #define KRB5_KPASSWD_ACCESSDENIED               5
  39 #define KRB5_KPASSWD_BAD_VERSION                6
  40 #define KRB5_KPASSWD_INITIAL_FLAG_NEEDED        7
  41
  42 /* Those are defined by kerberos-set-passwd-02.txt and are probably
  43  * not supported by M$ implementation */
  44 #define KRB5_KPASSWD_POLICY_REJECT              8
  45 #define KRB5_KPASSWD_BAD_PRINCIPAL              9
  46 #define KRB5_KPASSWD_ETYPE_NOSUPP               10
  47
  48 /* This implements kerberos password change protocol as specified in
  49  * kerb-chg-password-02.txt and kerberos-set-passwd-02.txt
  50  * as well as microsoft version of the protocol
  51  * as specified in kerberos-set-passwd-00.txt
  52  */
  53 static DATA_BLOB encode_krb5_setpw(const char *principal, const char *password)
  54 {
  55         char* princ_part1 = NULL;
  56         char* princ_part2 = NULL;
  57         char* realm = NULL;
  58         char* c;
  59         char* princ;
  60
  61         ASN1_DATA req;
  62         DATA_BLOB ret;
  63
  64
  65         princ = SMB_STRDUP(principal);
  66
  67         if ((c = strchr_m(princ, '/')) == NULL) {
  68             c = princ;
  69         } else {
  70             *c = '\0';
  71             c++;
  72             princ_part1 = princ;
  73         }
  74
  75         princ_part2 = c;
  76
  77         if ((c = strchr_m(c, '@')) != NULL) {
  78             *c = '\0';
  79             c++;
  80             realm = c;
  81         }
  82
  83         memset(&req, 0, sizeof(req));
  84
  85         asn1_push_tag(&req, ASN1_SEQUENCE(0));
  86         asn1_push_tag(&req, ASN1_CONTEXT(0));
  87         asn1_write_OctetString(&req, password, strlen(password));
  88         asn1_pop_tag(&req);
  89
  90         asn1_push_tag(&req, ASN1_CONTEXT(1));
  91         asn1_push_tag(&req, ASN1_SEQUENCE(0));
  92
  93         asn1_push_tag(&req, ASN1_CONTEXT(0));
  94         asn1_write_Integer(&req, 1);
  95         asn1_pop_tag(&req);
  96
  97         asn1_push_tag(&req, ASN1_CONTEXT(1));
  98         asn1_push_tag(&req, ASN1_SEQUENCE(0));
  99
 100         if (princ_part1)
 101             asn1_write_GeneralString(&req, princ_part1);
 102
 103         asn1_write_GeneralString(&req, princ_part2);
 104         asn1_pop_tag(&req);
 105         asn1_pop_tag(&req);
 106         asn1_pop_tag(&req);
 107         asn1_pop_tag(&req);
 108
 109         asn1_push_tag(&req, ASN1_CONTEXT(2));
 110         asn1_write_GeneralString(&req, realm);
 111         asn1_pop_tag(&req);
 112         asn1_pop_tag(&req);
 113
 114         ret = data_blob(req.data, req.length);
 115         asn1_free(&req);
 116
 117         free(princ);
 118
 119         return ret;
 120 }
 121
 122 static krb5_error_code build_kpasswd_request(uint16 pversion,
 123                                            krb5_context context,
 124                                            krb5_auth_context auth_context,
 125                                            krb5_data *ap_req,
 126                                            const char *princ,
 127                                            const char *passwd,
 128                                            krb5_data *packet)
 129 {
 130         krb5_error_code ret;
 131         krb5_data cipherpw;
 132         krb5_data encoded_setpw;
 133         krb5_replay_data replay;
 134         char *p;
 135         DATA_BLOB setpw;
 136
 137         ret = krb5_auth_con_setflags(context,
 138                                      auth_context,KRB5_AUTH_CONTEXT_DO_SEQUENCE);
 139         if (ret) {
 140                 DEBUG(1,("krb5_auth_con_setflags failed (%s)\n",
 141                          error_message(ret)));
 142                 return ret;
 143         }
 144
 145         /* handle protocol differences in chpw and setpw */
 146         if (pversion  == KRB5_KPASSWD_VERS_CHANGEPW)
 147                 setpw = data_blob(passwd, strlen(passwd));
 148         else if (pversion == KRB5_KPASSWD_VERS_SETPW ||
 149                  pversion == KRB5_KPASSWD_VERS_SETPW_ALT)
 150                 setpw = encode_krb5_setpw(princ, passwd);
 151         else
 152                 return EINVAL;
 153
 154         encoded_setpw.data = (char *)setpw.data;
 155         encoded_setpw.length = setpw.length;
 156
 157         ret = krb5_mk_priv(context, auth_context,
 158                            &encoded_setpw, &cipherpw, &replay);
 159
 160         data_blob_free(&setpw);         /*from 'encode_krb5_setpw(...)' */
 161
 162         if (ret) {
 163                 DEBUG(1,("krb5_mk_priv failed (%s)\n", error_message(ret)));
 164                 return ret;
 165         }
 166
 167         packet->data = (char *)SMB_MALLOC(ap_req->length + cipherpw.length + 6);
 168         if (!packet->data)
 169                 return -1;
 170
 171         /* see the RFC for details */
 172         p = ((char *)packet->data) + 2;
 173         RSSVAL(p, 0, pversion);
 174         p += 2;
 175         RSSVAL(p, 0, ap_req->length);
 176         p += 2;
 177         memcpy(p, ap_req->data, ap_req->length);
 178         p += ap_req->length;
 179         memcpy(p, cipherpw.data, cipherpw.length);
 180         p += cipherpw.length;
 181         packet->length = PTR_DIFF(p,packet->data);
 182         RSSVAL(packet->data, 0, packet->length);
 183
 184         free(cipherpw.data);    /* from 'krb5_mk_priv(...)' */
 185
 186         return 0;
 187 }
 188
 189 static const struct kpasswd_errors {
 190         int result_code;
 191         const char *error_string;
 192 } kpasswd_errors[] = {
 193         {KRB5_KPASSWD_MALFORMED, "Malformed request error"},
 194         {KRB5_KPASSWD_HARDERROR, "Server error"},
 195         {KRB5_KPASSWD_AUTHERROR, "Authentication error"},
 196         {KRB5_KPASSWD_SOFTERROR, "Password change rejected"},
 197         {KRB5_KPASSWD_ACCESSDENIED, "Client does not have proper authorization"},
 198         {KRB5_KPASSWD_BAD_VERSION, "Protocol version not supported"},
 199         {KRB5_KPASSWD_INITIAL_FLAG_NEEDED, "Authorization ticket must have initial flag set"},
 200         {KRB5_KPASSWD_POLICY_REJECT, "Password rejected due to policy requirements"},
 201         {KRB5_KPASSWD_BAD_PRINCIPAL, "Target principal does not exist"},
 202         {KRB5_KPASSWD_ETYPE_NOSUPP, "Unsupported encryption type"},
 203         {0, NULL}
 204 };
 205
 206 static krb5_error_code setpw_result_code_string(krb5_context context,
 207                                                 int result_code,
 208                                                 const char **code_string)
 209 {
 210         unsigned int idx = 0;
 211
 212         while (kpasswd_errors[idx].error_string != NULL) {
 213                 if (kpasswd_errors[idx].result_code ==
 214                     result_code) {
 215                         *code_string = kpasswd_errors[idx].error_string;
 216                         return 0;
 217                 }
 218                 idx++;
 219         }
 220         *code_string = "Password change failed";
 221         return (0);
 222 }
 223
 224  krb5_error_code kpasswd_err_to_krb5_err(krb5_error_code res_code)
 225 {
 226         switch(res_code) {
 227                 case KRB5_KPASSWD_ACCESSDENIED:
 228                         return KRB5KDC_ERR_BADOPTION;
 229                 case KRB5_KPASSWD_INITIAL_FLAG_NEEDED:
 230                         return KRB5KDC_ERR_BADOPTION;
 231                         /* return KV5M_ALT_METHOD; MIT-only define */
 232                 case KRB5_KPASSWD_ETYPE_NOSUPP:
 233                         return KRB5KDC_ERR_ETYPE_NOSUPP;
 234                 case KRB5_KPASSWD_BAD_PRINCIPAL:
 235                         return KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
 236                 case KRB5_KPASSWD_POLICY_REJECT:
 237                 case KRB5_KPASSWD_SOFTERROR:
 238                         return KRB5KDC_ERR_POLICY;
 239                 default:
 240                         return KRB5KRB_ERR_GENERIC;
 241         }
 242 }
 243 static krb5_error_code parse_setpw_reply(krb5_context context,
 244                                          krb5_auth_context auth_context,
 245                                          krb5_data *packet)
 246 {
 247         krb5_data ap_rep;
 248         char *p;
 249         int vnum, ret, res_code;
 250         krb5_data cipherresult;
 251         krb5_data clearresult;
 252         krb5_ap_rep_enc_part *ap_rep_enc;
 253         krb5_replay_data replay;
 254
 255         if (packet->length < 4) {
 256                 return KRB5KRB_AP_ERR_MODIFIED;
 257         }
 258
 259         p = packet->data;
 260
 261         if (((char *)packet->data)[0] == 0x7e || ((char *)packet->data)[0] == 0x5e) {
 262                 /* it's an error packet. We should parse it ... */
 263                 DEBUG(1,("Got error packet 0x%x from kpasswd server\n",
 264                          ((char *)packet->data)[0]));
 265                 return KRB5KRB_AP_ERR_MODIFIED;
 266         }
 267
 268         if (RSVAL(p, 0) != packet->length) {
 269                 DEBUG(1,("Bad packet length (%d/%d) from kpasswd server\n",
 270                          RSVAL(p, 0), packet->length));
 271                 return KRB5KRB_AP_ERR_MODIFIED;
 272         }
 273
 274         p += 2;
 275
 276         vnum = RSVAL(p, 0); p += 2;
 277
 278         /* FIXME: According to standard there is only one type of reply */
 279         if (vnum != KRB5_KPASSWD_VERS_SETPW &&
 280             vnum != KRB5_KPASSWD_VERS_SETPW_ALT &&
 281             vnum != KRB5_KPASSWD_VERS_CHANGEPW) {
 282                 DEBUG(1,("Bad vnum (%d) from kpasswd server\n", vnum));
 283                 return KRB5KDC_ERR_BAD_PVNO;
 284         }
 285
 286         ap_rep.length = RSVAL(p, 0); p += 2;
 287
 288         if (p + ap_rep.length >= (char *)packet->data + packet->length) {
 289                 DEBUG(1,("ptr beyond end of packet from kpasswd server\n"));
 290                 return KRB5KRB_AP_ERR_MODIFIED;
 291         }
 292
 293         if (ap_rep.length == 0) {
 294                 DEBUG(1,("got unencrypted setpw result?!\n"));
 295                 return KRB5KRB_AP_ERR_MODIFIED;
 296         }
 297
 298         /* verify ap_rep */
 299         ap_rep.data = p;
 300         p += ap_rep.length;
 301
 302         ret = krb5_rd_rep(context, auth_context, &ap_rep, &ap_rep_enc);
 303         if (ret) {
 304                 DEBUG(1,("failed to rd setpw reply (%s)\n", error_message(ret)));
 305                 return KRB5KRB_AP_ERR_MODIFIED;
 306         }
 307
 308         krb5_free_ap_rep_enc_part(context, ap_rep_enc);
 309
 310         cipherresult.data = p;
 311         cipherresult.length = ((char *)packet->data + packet->length) - p;
 312
 313         ret = krb5_rd_priv(context, auth_context, &cipherresult, &clearresult,
 314                            &replay);
 315         if (ret) {
 316                 DEBUG(1,("failed to decrypt setpw reply (%s)\n", error_message(ret)));
 317                 return KRB5KRB_AP_ERR_MODIFIED;
 318         }
 319
 320         if (clearresult.length < 2) {
 321                 free(clearresult.data);
 322                 ret = KRB5KRB_AP_ERR_MODIFIED;
 323                 return KRB5KRB_AP_ERR_MODIFIED;
 324         }
 325
 326         p = clearresult.data;
 327
 328         res_code = RSVAL(p, 0);
 329
 330         free(clearresult.data);
 331
 332         if ((res_code < KRB5_KPASSWD_SUCCESS) ||
 333             (res_code > KRB5_KPASSWD_ETYPE_NOSUPP)) {
 334                 return KRB5KRB_AP_ERR_MODIFIED;
 335         }
 336
 337         if(res_code == KRB5_KPASSWD_SUCCESS)
 338                         return 0;
 339         else {
 340                 const char *errstr;
 341                 setpw_result_code_string(context, res_code, &errstr);
 342                 DEBUG(1, ("Error changing password: %s (%d)\n", errstr, res_code));
 343
 344                 return kpasswd_err_to_krb5_err(res_code);
 345         }
 346 }
 347
 348 static ADS_STATUS do_krb5_kpasswd_request(krb5_context context,
 349                                           const char *kdc_host,
 350                                           uint16 pversion,
 351                                           krb5_creds *credsp,
 352                                           const char *princ,
 353                                           const char *newpw)
 354 {
 355         krb5_auth_context auth_context = NULL;
 356         krb5_data ap_req, chpw_req, chpw_rep;
 357         int ret, sock;
 358         socklen_t addr_len;
 359         struct sockaddr remote_addr, local_addr;
 360         krb5_address local_kaddr, remote_kaddr;
 361
 362         ret = krb5_mk_req_extended(context, &auth_context, AP_OPTS_USE_SUBKEY,
 363                                    NULL, credsp, &ap_req);
 364         if (ret) {
 365                 DEBUG(1,("krb5_mk_req_extended failed (%s)\n", error_message(ret)));
 366                 return ADS_ERROR_KRB5(ret);
 367         }
 368
 369         sock = open_udp_socket(kdc_host, DEFAULT_KPASSWD_PORT);
 370         if (sock == -1) {
 371                 int rc = errno;
 372                 free(ap_req.data);
 373                 krb5_auth_con_free(context, auth_context);
 374                 DEBUG(1,("failed to open kpasswd socket to %s (%s)\n",
 375                          kdc_host, strerror(errno)));
 376                 return ADS_ERROR_SYSTEM(rc);
 377         }
 378
 379         addr_len = sizeof(remote_addr);
 380         getpeername(sock, &remote_addr, &addr_len);
 381         addr_len = sizeof(local_addr);
 382         getsockname(sock, &local_addr, &addr_len);
 383
 384         setup_kaddr(&remote_kaddr, &remote_addr);
 385         setup_kaddr(&local_kaddr, &local_addr);
 386
 387         ret = krb5_auth_con_setaddrs(context, auth_context, &local_kaddr, NULL);
 388         if (ret) {
 389                 close(sock);
 390                 free(ap_req.data);
 391                 krb5_auth_con_free(context, auth_context);
 392                 DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n", error_message(ret)));
 393                 return ADS_ERROR_KRB5(ret);
 394         }
 395
 396         ret = build_kpasswd_request(pversion, context, auth_context, &ap_req,
 397                                   princ, newpw, &chpw_req);
 398         if (ret) {
 399                 close(sock);
 400                 free(ap_req.data);
 401                 krb5_auth_con_free(context, auth_context);
 402                 DEBUG(1,("build_setpw_request failed (%s)\n", error_message(ret)));
 403                 return ADS_ERROR_KRB5(ret);
 404         }
 405
 406         if (write(sock, chpw_req.data, chpw_req.length) != chpw_req.length) {
 407                 close(sock);
 408                 free(chpw_req.data);
 409                 free(ap_req.data);
 410                 krb5_auth_con_free(context, auth_context);
 411                 DEBUG(1,("send of chpw failed (%s)\n", strerror(errno)));
 412                 return ADS_ERROR_SYSTEM(errno);
 413         }
 414
 415         free(chpw_req.data);
 416
 417         chpw_rep.length = 1500;
 418         chpw_rep.data = (char *) SMB_MALLOC(chpw_rep.length);
 419         if (!chpw_rep.data) {
 420                 close(sock);
 421                 free(ap_req.data);
 422                 krb5_auth_con_free(context, auth_context);
 423                 DEBUG(1,("send of chpw failed (%s)\n", strerror(errno)));
 424                 errno = ENOMEM;
 425                 return ADS_ERROR_SYSTEM(errno);
 426         }
 427
 428         ret = read(sock, chpw_rep.data, chpw_rep.length);
 429         if (ret < 0) {
 430                 close(sock);
 431                 free(chpw_rep.data);
 432                 free(ap_req.data);
 433                 krb5_auth_con_free(context, auth_context);
 434                 DEBUG(1,("recv of chpw reply failed (%s)\n", strerror(errno)));
 435                 return ADS_ERROR_SYSTEM(errno);
 436         }
 437
 438         close(sock);
 439         chpw_rep.length = ret;
 440
 441         ret = krb5_auth_con_setaddrs(context, auth_context, NULL,&remote_kaddr);
 442         if (ret) {
 443                 free(chpw_rep.data);
 444                 free(ap_req.data);
 445                 krb5_auth_con_free(context, auth_context);
 446                 DEBUG(1,("krb5_auth_con_setaddrs on reply failed (%s)\n",
 447                          error_message(ret)));
 448                 return ADS_ERROR_KRB5(ret);
 449         }
 450
 451         ret = parse_setpw_reply(context, auth_context, &chpw_rep);
 452         free(chpw_rep.data);
 453
 454         if (ret) {
 455                 free(ap_req.data);
 456                 krb5_auth_con_free(context, auth_context);
 457                 DEBUG(1,("parse_setpw_reply failed (%s)\n",
 458                          error_message(ret)));
 459                 return ADS_ERROR_KRB5(ret);
 460         }
 461
 462         free(ap_req.data);
 463         krb5_auth_con_free(context, auth_context);
 464
 465         return ADS_SUCCESS;
 466 }
 467
 468 ADS_STATUS ads_krb5_set_password(const char *kdc_host, const char *princ,
 469                                  const char *newpw, int time_offset)
 470 {
 471
 472         ADS_STATUS aret;
 473         krb5_error_code ret = 0;
 474         krb5_context context = NULL;
 475         krb5_principal principal = NULL;
 476         char *princ_name = NULL;
 477         char *realm = NULL;
 478         krb5_creds creds, *credsp = NULL;
 479 #if KRB5_PRINC_REALM_RETURNS_REALM
 480         krb5_realm orig_realm;
 481 #else
 482         krb5_data orig_realm;
 483 #endif
 484         krb5_ccache ccache = NULL;
 485
 486         ZERO_STRUCT(creds);
 487
 488         initialize_krb5_error_table();
 489         ret = krb5_init_context(&context);
 490         if (ret) {
 491                 DEBUG(1,("Failed to init krb5 context (%s)\n", error_message(ret)));
 492                 return ADS_ERROR_KRB5(ret);
 493         }
 494
 495         if (time_offset != 0) {
 496                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
 497         }
 498
 499         ret = krb5_cc_default(context, &ccache);
 500         if (ret) {
 501                 krb5_free_context(context);
 502                 DEBUG(1,("Failed to get default creds (%s)\n", error_message(ret)));
 503                 return ADS_ERROR_KRB5(ret);
 504         }
 505
 506         realm = strchr_m(princ, '@');
 507         if (!realm) {
 508                 krb5_cc_close(context, ccache);
 509                 krb5_free_context(context);
 510                 DEBUG(1,("Failed to get realm\n"));
 511                 return ADS_ERROR_KRB5(-1);
 512         }
 513         realm++;
 514
 515         asprintf(&princ_name, "kadmin/changepw@%s", realm);
 516         ret = krb5_parse_name(context, princ_name, &creds.server);
 517         if (ret) {
 518                 krb5_cc_close(context, ccache);
 519                 krb5_free_context(context);
 520                 DEBUG(1,("Failed to parse kadmin/changepw (%s)\n", error_message(ret)));
 521                 return ADS_ERROR_KRB5(ret);
 522         }
 523         free(princ_name);
 524
 525         /* parse the principal we got as a function argument */
 526         ret = krb5_parse_name(context, princ, &principal);
 527         if (ret) {
 528                 krb5_cc_close(context, ccache);
 529                 krb5_free_principal(context, creds.server);
 530                 krb5_free_context(context);
 531                 DEBUG(1,("Failed to parse %s (%s)\n", princ_name, error_message(ret)));
 532                 return ADS_ERROR_KRB5(ret);
 533         }
 534
 535         /* The creds.server principal takes ownership of this memory.
 536                 Remember to set back to original value before freeing. */
 537         orig_realm = *krb5_princ_realm(context, creds.server);
 538         krb5_princ_set_realm(context, creds.server, krb5_princ_realm(context, principal));
 539
 540         ret = krb5_cc_get_principal(context, ccache, &creds.client);
 541         if (ret) {
 542                 krb5_cc_close(context, ccache);
 543                 krb5_princ_set_realm(context, creds.server, &orig_realm);
 544                 krb5_free_principal(context, creds.server);
 545                 krb5_free_principal(context, principal);
 546                 krb5_free_context(context);
 547                 DEBUG(1,("Failed to get principal from ccache (%s)\n",
 548                          error_message(ret)));
 549                 return ADS_ERROR_KRB5(ret);
 550         }
 551
 552         ret = krb5_get_credentials(context, 0, ccache, &creds, &credsp);
 553         if (ret) {
 554                 krb5_cc_close(context, ccache);
 555                 krb5_free_principal(context, creds.client);
 556                 krb5_princ_set_realm(context, creds.server, &orig_realm);
 557                 krb5_free_principal(context, creds.server);
 558                 krb5_free_principal(context, principal);
 559                 krb5_free_context(context);
 560                 DEBUG(1,("krb5_get_credentials failed (%s)\n", error_message(ret)));
 561                 return ADS_ERROR_KRB5(ret);
 562         }
 563
 564         /* we might have to call krb5_free_creds(...) from now on ... */
 565
 566         aret = do_krb5_kpasswd_request(context, kdc_host,
 567                                        KRB5_KPASSWD_VERS_SETPW,
 568                                        credsp, princ, newpw);
 569
 570         krb5_free_creds(context, credsp);
 571         krb5_free_principal(context, creds.client);
 572         krb5_princ_set_realm(context, creds.server, &orig_realm);
 573         krb5_free_principal(context, creds.server);
 574         krb5_free_principal(context, principal);
 575         krb5_cc_close(context, ccache);
 576         krb5_free_context(context);
 577
 578         return aret;
 579 }
 580
 581 /*
 582   we use a prompter to avoid a crash bug in the kerberos libs when
 583   dealing with empty passwords
 584   this prompter is just a string copy ...
 585 */
 586 static krb5_error_code
 587 kerb_prompter(krb5_context ctx, void *data,
 588                const char *name,
 589                const char *banner,
 590                int num_prompts,
 591                krb5_prompt prompts[])
 592 {
 593         if (num_prompts == 0) return 0;
 594
 595         memset(prompts[0].reply->data, 0, prompts[0].reply->length);
 596         if (prompts[0].reply->length > 0) {
 597                 if (data) {
 598                         strncpy(prompts[0].reply->data, data, prompts[0].reply->length-1);
 599                         prompts[0].reply->length = strlen(prompts[0].reply->data);
 600                 } else {
 601                         prompts[0].reply->length = 0;
 602                 }
 603         }
 604         return 0;
 605 }
 606
 607 static ADS_STATUS ads_krb5_chg_password(const char *kdc_host,
 608                                         const char *principal,
 609                                         const char *oldpw,
 610                                         const char *newpw,
 611                                         int time_offset)
 612 {
 613     ADS_STATUS aret;
 614     krb5_error_code ret;
 615     krb5_context context = NULL;
 616     krb5_principal princ;
 617     krb5_get_init_creds_opt opts;
 618     krb5_creds creds;
 619     char *chpw_princ = NULL, *password;
 620
 621     initialize_krb5_error_table();
 622     ret = krb5_init_context(&context);
 623     if (ret) {
 624         DEBUG(1,("Failed to init krb5 context (%s)\n", error_message(ret)));
 625         return ADS_ERROR_KRB5(ret);
 626     }
 627
 628     if ((ret = krb5_parse_name(context, principal,
 629                                     &princ))) {
 630         krb5_free_context(context);
 631         DEBUG(1,("Failed to parse %s (%s)\n", principal, error_message(ret)));
 632         return ADS_ERROR_KRB5(ret);
 633     }
 634
 635     krb5_get_init_creds_opt_init(&opts);
 636     krb5_get_init_creds_opt_set_tkt_life(&opts, 5*60);
 637     krb5_get_init_creds_opt_set_renew_life(&opts, 0);
 638     krb5_get_init_creds_opt_set_forwardable(&opts, 0);
 639     krb5_get_init_creds_opt_set_proxiable(&opts, 0);
 640
 641     /* We have to obtain an INITIAL changepw ticket for changing password */
 642     asprintf(&chpw_princ, "kadmin/changepw@%s",
 643                                 (char *) krb5_princ_realm(context, princ));
 644     password = SMB_STRDUP(oldpw);
 645     ret = krb5_get_init_creds_password(context, &creds, princ, password,
 646                                            kerb_prompter, NULL,
 647                                            0, chpw_princ, &opts);
 648     SAFE_FREE(chpw_princ);
 649     SAFE_FREE(password);
 650
 651     if (ret) {
 652       if (ret == KRB5KRB_AP_ERR_BAD_INTEGRITY)
 653         DEBUG(1,("Password incorrect while getting initial ticket"));
 654       else
 655         DEBUG(1,("krb5_get_init_creds_password failed (%s)\n", error_message(ret)));
 656
 657         krb5_free_principal(context, princ);
 658         krb5_free_context(context);
 659         return ADS_ERROR_KRB5(ret);
 660     }
 661
 662     aret = do_krb5_kpasswd_request(context, kdc_host,
 663                                    KRB5_KPASSWD_VERS_CHANGEPW,
 664                                    &creds, principal, newpw);
 665
 666     krb5_free_principal(context, princ);
 667     krb5_free_context(context);
 668
 669     return aret;
 670 }
 671
 672
 673 ADS_STATUS kerberos_set_password(const char *kpasswd_server,
 674                                  const char *auth_principal, const char *auth_password,
 675                                  const char *target_principal, const char *new_password,
 676                                  int time_offset)
 677 {
 678     int ret;
 679
 680     if ((ret = kerberos_kinit_password(auth_principal, auth_password, time_offset, NULL, NULL, NULL, False, 0))) {
 681         DEBUG(1,("Failed kinit for principal %s (%s)\n", auth_principal, error_message(ret)));
 682         return ADS_ERROR_KRB5(ret);
 683     }
 684
 685     if (!strcmp(auth_principal, target_principal))
 686         return ads_krb5_chg_password(kpasswd_server, target_principal,
 687                                      auth_password, new_password, time_offset);
 688     else
 689         return ads_krb5_set_password(kpasswd_server, target_principal,
 690                                      new_password, time_offset);
 691 }
 692
 693
 694 /**
 695  * Set the machine account password
 696  * @param ads connection to ads server
 697  * @param hostname machine whose password is being set
 698  * @param password new password
 699  * @return status of password change
 700  **/
 701 ADS_STATUS ads_set_machine_password(ADS_STRUCT *ads,
 702                                     const char *machine_account,
 703                                     const char *password)
 704 {
 705         ADS_STATUS status;
 706         char *principal = NULL;
 707
 708         /*
 709           we need to use the '$' form of the name here (the machine account name),
 710           as otherwise the server might end up setting the password for a user
 711           instead
 712          */
 713         asprintf(&principal, "%s@%s", machine_account, ads->config.realm);
 714
 715         status = ads_krb5_set_password(ads->auth.kdc_server, principal,
 716                                        password, ads->auth.time_offset);
 717
 718         free(principal);
 719
 720         return status;
 721 }
 722
 723
 724
 725 #endif