1 /* 2 * Copyright (c) 1997 - 2003 Kungliga Tekniska H�gskolan 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 <krb5_locl.h> 35 36 RCSID("$Id: changepw.c,v 1.38.2.1 2004/06/21 08:38:10 lha Exp $"); 37 38 static void 39 str2data (krb5_data *d, 40 const char *fmt, 41 ...) __attribute__ ((format (printf, 2, 3))); 42 43 static void 44 str2data (krb5_data *d, 45 const char *fmt, 46 ...) 47 { 48 va_list args; 49 50 va_start(args, fmt); 51 d->length = vasprintf ((char **)&d->data, fmt, args); 52 va_end(args); 53 } 54 55 /* 56 * Change password protocol defined by 57 * draft-ietf-cat-kerb-chg-password-02.txt 58 * 59 * Share the response part of the protocol with MS set password 60 * (RFC3244) 61 */ 62 63 static krb5_error_code 64 chgpw_send_request (krb5_context context, 65 krb5_auth_context *auth_context, 66 krb5_creds *creds, 67 krb5_principal targprinc, 68 int is_stream, 69 int sock, 70 char *passwd, 71 const char *host) 72 { 73 krb5_error_code ret; 74 krb5_data ap_req_data; 75 krb5_data krb_priv_data; 76 krb5_data passwd_data; 77 size_t len; 78 u_char header[6]; 79 u_char *p; 80 struct iovec iov[3]; 81 struct msghdr msghdr; 82 83 if (is_stream) 84 return KRB5_KPASSWD_MALFORMED; 85 86 if (targprinc && 87 krb5_principal_compare(context, creds->client, targprinc) != TRUE) 88 return KRB5_KPASSWD_MALFORMED; 89 90 krb5_data_zero (&ap_req_data); 91 92 ret = krb5_mk_req_extended (context, 93 auth_context, 94 AP_OPTS_MUTUAL_REQUIRED | AP_OPTS_USE_SUBKEY, 95 NULL, /* in_data */ 96 creds, 97 &ap_req_data); 98 if (ret) 99 return ret; 100 101 passwd_data.data = passwd; 102 passwd_data.length = strlen(passwd); 103 104 krb5_data_zero (&krb_priv_data); 105 106 ret = krb5_mk_priv (context, 107 *auth_context, 108 &passwd_data, 109 &krb_priv_data, 110 NULL); 111 if (ret) 112 goto out2; 113 114 len = 6 + ap_req_data.length + krb_priv_data.length; 115 p = header; 116 *p++ = (len >> 8) & 0xFF; 117 *p++ = (len >> 0) & 0xFF; 118 *p++ = 0; 119 *p++ = 1; 120 *p++ = (ap_req_data.length >> 8) & 0xFF; 121 *p++ = (ap_req_data.length >> 0) & 0xFF; 122 123 memset(&msghdr, 0, sizeof(msghdr)); 124 msghdr.msg_name = NULL; 125 msghdr.msg_namelen = 0; 126 msghdr.msg_iov = iov; 127 msghdr.msg_iovlen = sizeof(iov)/sizeof(*iov); 128 #if 0 129 msghdr.msg_control = NULL; 130 msghdr.msg_controllen = 0; 131 #endif 132 133 iov[0].iov_base = (void*)header; 134 iov[0].iov_len = 6; 135 iov[1].iov_base = ap_req_data.data; 136 iov[1].iov_len = ap_req_data.length; 137 iov[2].iov_base = krb_priv_data.data; 138 iov[2].iov_len = krb_priv_data.length; 139 140 if (sendmsg (sock, &msghdr, 0) < 0) { 141 ret = errno; 142 krb5_set_error_string(context, "sendmsg %s: %s", host, strerror(ret)); 143 } 144 145 krb5_data_free (&krb_priv_data); 146 out2: 147 krb5_data_free (&ap_req_data); 148 return ret; 149 } 150 151 /* 152 * Set password protocol as defined by RFC3244 -- 153 * Microsoft Windows 2000 Kerberos Change Password and Set Password Protocols 154 */ 155 156 static krb5_error_code 157 setpw_send_request (krb5_context context, 158 krb5_auth_context *auth_context, 159 krb5_creds *creds, 160 krb5_principal targprinc, 161 int is_stream, 162 int sock, 163 char *passwd, 164 const char *host) 165 { 166 krb5_error_code ret; 167 krb5_data ap_req_data; 168 krb5_data krb_priv_data; 169 krb5_data pwd_data; 170 ChangePasswdDataMS chpw; 171 size_t len; 172 u_char header[4 + 6]; 173 u_char *p; 174 struct iovec iov[3]; 175 struct msghdr msghdr; 176 177 krb5_data_zero (&ap_req_data); 178 179 ret = krb5_mk_req_extended (context, 180 auth_context, 181 AP_OPTS_MUTUAL_REQUIRED | AP_OPTS_USE_SUBKEY, 182 NULL, /* in_data */ 183 creds, 184 &ap_req_data); 185 if (ret) 186 return ret; 187 188 chpw.newpasswd.length = strlen(passwd); 189 chpw.newpasswd.data = passwd; 190 if (targprinc) { 191 chpw.targname = &targprinc->name; 192 chpw.targrealm = &targprinc->realm; 193 } else { 194 chpw.targname = NULL; 195 chpw.targrealm = NULL; 196 } 197 198 ASN1_MALLOC_ENCODE(ChangePasswdDataMS, pwd_data.data, pwd_data.length, 199 &chpw, &len, ret); 200 if (ret) { 201 krb5_data_free (&ap_req_data); 202 return ret; 203 } 204 205 if(pwd_data.length != len) 206 krb5_abortx(context, "internal error in ASN.1 encoder"); 207 208 ret = krb5_mk_priv (context, 209 *auth_context, 210 &pwd_data, 211 &krb_priv_data, 212 NULL); 213 if (ret) 214 goto out2; 215 216 len = 6 + ap_req_data.length + krb_priv_data.length; 217 p = header; 218 if (is_stream) { 219 _krb5_put_int(p, len, 4); 220 p += 4; 221 } 222 *p++ = (len >> 8) & 0xFF; 223 *p++ = (len >> 0) & 0xFF; 224 *p++ = 0xff; 225 *p++ = 0x80; 226 *p++ = (ap_req_data.length >> 8) & 0xFF; 227 *p++ = (ap_req_data.length >> 0) & 0xFF; 228 229 memset(&msghdr, 0, sizeof(msghdr)); 230 msghdr.msg_name = NULL; 231 msghdr.msg_namelen = 0; 232 msghdr.msg_iov = iov; 233 msghdr.msg_iovlen = sizeof(iov)/sizeof(*iov); 234 #if 0 235 msghdr.msg_control = NULL; 236 msghdr.msg_controllen = 0; 237 #endif 238 239 iov[0].iov_base = (void*)header; 240 if (is_stream) 241 iov[0].iov_len = 10; 242 else 243 iov[0].iov_len = 6; 244 iov[1].iov_base = ap_req_data.data; 245 iov[1].iov_len = ap_req_data.length; 246 iov[2].iov_base = krb_priv_data.data; 247 iov[2].iov_len = krb_priv_data.length; 248 249 if (sendmsg (sock, &msghdr, 0) < 0) { 250 ret = errno; 251 krb5_set_error_string(context, "sendmsg %s: %s", host, strerror(ret)); 252 } 253 254 krb5_data_free (&krb_priv_data); 255 out2: 256 krb5_data_free (&ap_req_data); 257 krb5_data_free (&pwd_data); 258 return ret; 259 } 260 261 static krb5_error_code 262 process_reply (krb5_context context, 263 krb5_auth_context auth_context, 264 int is_stream, 265 int sock, 266 int *result_code, 267 krb5_data *result_code_string, 268 krb5_data *result_string, 269 const char *host) 270 { 271 krb5_error_code ret; 272 u_char reply[1024 * 3]; 273 ssize_t len; 274 u_int16_t pkt_len, pkt_ver; 275 krb5_data ap_rep_data; 276 int save_errno; 277 278 len = 0; 279 if (is_stream) { 280 while (len < sizeof(reply)) { 281 unsigned long size; 282 283 ret = recvfrom (sock, reply + len, sizeof(reply) - len, 284 0, NULL, NULL); 285 if (ret < 0) { 286 save_errno = errno; 287 krb5_set_error_string(context, "recvfrom %s: %s", 288 host, strerror(save_errno)); 289 return save_errno; 290 } else if (ret == 0) { 291 krb5_set_error_string(context, "recvfrom timeout %s", host); 292 return 1; 293 } 294 len += ret; 295 if (len < 4) 296 continue; 297 _krb5_get_int(reply, &size, 4); 298 if (size + 4 < len) 299 continue; 300 memmove(reply, reply + 4, size); 301 len = size; 302 break; 303 } 304 if (len == sizeof(reply)) { 305 krb5_set_error_string(context, "message too large from %s", 306 host); 307 return ENOMEM; 308 } 309 } else { 310 ret = recvfrom (sock, reply, sizeof(reply), 0, NULL, NULL); 311 if (ret < 0) { 312 save_errno = errno; 313 krb5_set_error_string(context, "recvfrom %s: %s", 314 host, strerror(save_errno)); 315 return save_errno; 316 } 317 len = ret; 318 } 319 320 if (len < 6) { 321 str2data (result_string, "server %s sent to too short message " 322 "(%d bytes)", host, len); 323 *result_code = KRB5_KPASSWD_MALFORMED; 324 return 0; 325 } 326 327 pkt_len = (reply[0] << 8) | (reply[1]); 328 pkt_ver = (reply[2] << 8) | (reply[3]); 329 330 if ((pkt_len != len) || (reply[1] == 0x7e || reply[1] == 0x5e)) { 331 KRB_ERROR error; 332 size_t size; 333 u_char *p; 334 335 memset(&error, 0, sizeof(error)); 336 337 ret = decode_KRB_ERROR(reply, len, &error, &size); 338 if (ret) 339 return ret; 340 341 if (error.e_data->length < 2) { 342 str2data(result_string, "server %s sent too short " 343 "e_data to print anything usable", host); 344 free_KRB_ERROR(&error); 345 *result_code = KRB5_KPASSWD_MALFORMED; 346 return 0; 347 } 348 349 p = error.e_data->data; 350 *result_code = (p[0] << 8) | p[1]; 351 if (error.e_data->length == 2) 352 str2data(result_string, "server only sent error code"); 353 else 354 krb5_data_copy (result_string, 355 p + 2, 356 error.e_data->length - 2); 357 free_KRB_ERROR(&error); 358 return 0; 359 } 360 361 if (pkt_len != len) { 362 str2data (result_string, "client: wrong len in reply"); 363 *result_code = KRB5_KPASSWD_MALFORMED; 364 return 0; 365 } 366 if (pkt_ver != KRB5_KPASSWD_VERS_CHANGEPW) { 367 str2data (result_string, 368 "client: wrong version number (%d)", pkt_ver); 369 *result_code = KRB5_KPASSWD_MALFORMED; 370 return 0; 371 } 372 373 ap_rep_data.data = reply + 6; 374 ap_rep_data.length = (reply[4] << 8) | (reply[5]); 375 376 if (reply + len < (u_char *)ap_rep_data.data + ap_rep_data.length) { 377 str2data (result_string, "client: wrong AP len in reply"); 378 *result_code = KRB5_KPASSWD_MALFORMED; 379 return 0; 380 } 381 382 if (ap_rep_data.length) { 383 krb5_ap_rep_enc_part *ap_rep; 384 krb5_data priv_data; 385 u_char *p; 386 387 priv_data.data = (u_char*)ap_rep_data.data + ap_rep_data.length; 388 priv_data.length = len - ap_rep_data.length - 6; 389 390 ret = krb5_rd_rep (context, 391 auth_context, 392 &ap_rep_data, 393 &ap_rep); 394 if (ret) 395 return ret; 396 397 krb5_free_ap_rep_enc_part (context, ap_rep); 398 399 ret = krb5_rd_priv (context, 400 auth_context, 401 &priv_data, 402 result_code_string, 403 NULL); 404 if (ret) { 405 krb5_data_free (result_code_string); 406 return ret; 407 } 408 409 if (result_code_string->length < 2) { 410 *result_code = KRB5_KPASSWD_MALFORMED; 411 str2data (result_string, 412 "client: bad length in result"); 413 return 0; 414 } 415 416 p = result_code_string->data; 417 418 *result_code = (p[0] << 8) | p[1]; 419 krb5_data_copy (result_string, 420 (unsigned char*)result_code_string->data + 2, 421 result_code_string->length - 2); 422 return 0; 423 } else { 424 KRB_ERROR error; 425 size_t size; 426 u_char *p; 427 428 ret = decode_KRB_ERROR(reply + 6, len - 6, &error, &size); 429 if (ret) { 430 return ret; 431 } 432 if (error.e_data->length < 2) { 433 krb5_warnx (context, "too short e_data to print anything usable"); 434 return 1; /* XXX */ 435 } 436 437 p = error.e_data->data; 438 *result_code = (p[0] << 8) | p[1]; 439 krb5_data_copy (result_string, 440 p + 2, 441 error.e_data->length - 2); 442 return 0; 443 } 444 } 445 446 447 /* 448 * change the password using the credentials in `creds' (for the 449 * principal indicated in them) to `newpw', storing the result of 450 * the operation in `result_*' and an error code or 0. 451 */ 452 453 typedef krb5_error_code (*kpwd_send_request) (krb5_context, 454 krb5_auth_context *, 455 krb5_creds *, 456 krb5_principal, 457 int, 458 int, 459 char *, 460 const char *); 461 typedef krb5_error_code (*kpwd_process_reply) (krb5_context, 462 krb5_auth_context, 463 int, 464 int, 465 int *, 466 krb5_data *, 467 krb5_data *, 468 const char *); 469 470 struct kpwd_proc { 471 const char *name; 472 int flags; 473 #define SUPPORT_TCP 1 474 #define SUPPORT_UDP 2 475 kpwd_send_request send_req; 476 kpwd_process_reply process_rep; 477 } procs[] = { 478 { 479 "MS set password", 480 SUPPORT_TCP|SUPPORT_UDP, 481 setpw_send_request, 482 process_reply 483 }, 484 { 485 "change password", 486 SUPPORT_UDP, 487 chgpw_send_request, 488 process_reply 489 }, 490 { NULL } 491 }; 492 493 static struct kpwd_proc * 494 find_chpw_proto(const char *name) 495 { 496 struct kpwd_proc *p; 497 for (p = procs; p->name != NULL; p++) { 498 if (strcmp(p->name, name) == 0) 499 return p; 500 } 501 return NULL; 502 } 503 504 /* 505 * 506 */ 507 508 static krb5_error_code 509 change_password_loop (krb5_context context, 510 krb5_creds *creds, 511 krb5_principal targprinc, 512 char *newpw, 513 int *result_code, 514 krb5_data *result_code_string, 515 krb5_data *result_string, 516 struct kpwd_proc *proc) 517 { 518 krb5_error_code ret; 519 krb5_auth_context auth_context = NULL; 520 krb5_krbhst_handle handle = NULL; 521 krb5_krbhst_info *hi; 522 int sock; 523 int i; 524 int done = 0; 525 krb5_realm realm = creds->client->realm; 526 527 ret = krb5_auth_con_init (context, &auth_context); 528 if (ret) 529 return ret; 530 531 krb5_auth_con_setflags (context, auth_context, 532 KRB5_AUTH_CONTEXT_DO_SEQUENCE); 533 534 ret = krb5_krbhst_init (context, realm, KRB5_KRBHST_CHANGEPW, &handle); 535 if (ret) 536 goto out; 537 538 while (!done && (ret = krb5_krbhst_next(context, handle, &hi)) == 0) { 539 struct addrinfo *ai, *a; 540 int is_stream; 541 542 switch (hi->proto) { 543 case KRB5_KRBHST_UDP: 544 if ((proc->flags & SUPPORT_UDP) == 0) 545 continue; 546 is_stream = 0; 547 break; 548 case KRB5_KRBHST_TCP: 549 if ((proc->flags & SUPPORT_TCP) == 0) 550 continue; 551 is_stream = 1; 552 break; 553 default: 554 continue; 555 } 556 557 ret = krb5_krbhst_get_addrinfo(context, hi, &ai); 558 if (ret) 559 continue; 560 561 for (a = ai; !done && a != NULL; a = a->ai_next) { 562 int replied = 0; 563 564 sock = socket (a->ai_family, a->ai_socktype, a->ai_protocol); 565 if (sock < 0) 566 continue; 567 568 ret = connect(sock, a->ai_addr, a->ai_addrlen); 569 if (ret < 0) { 570 close (sock); 571 goto out; 572 } 573 574 ret = krb5_auth_con_genaddrs (context, auth_context, sock, 575 KRB5_AUTH_CONTEXT_GENERATE_LOCAL_ADDR); 576 if (ret) { 577 close (sock); 578 goto out; 579 } 580 581 for (i = 0; !done && i < 5; ++i) { 582 fd_set fdset; 583 struct timeval tv; 584 585 if (!replied) { 586 replied = 0; 587 588 ret = (*proc->send_req) (context, 589 &auth_context, 590 creds, 591 targprinc, 592 is_stream, 593 sock, 594 newpw, 595 hi->hostname); 596 if (ret) { 597 close(sock); 598 goto out; 599 } 600 } 601 602 if (sock >= FD_SETSIZE) { 603 krb5_set_error_string(context, "fd %d too large", sock); 604 ret = ERANGE; 605 close (sock); 606 goto out; 607 } 608 609 FD_ZERO(&fdset); 610 FD_SET(sock, &fdset); 611 tv.tv_usec = 0; 612 tv.tv_sec = 1 + (1 << i); 613 614 ret = select (sock + 1, &fdset, NULL, NULL, &tv); 615 if (ret < 0 && errno != EINTR) { 616 close(sock); 617 goto out; 618 } 619 if (ret == 1) { 620 ret = (*proc->process_rep) (context, 621 auth_context, 622 is_stream, 623 sock, 624 result_code, 625 result_code_string, 626 result_string, 627 hi->hostname); 628 if (ret == 0) 629 done = 1; 630 else if (i > 0 && ret == KRB5KRB_AP_ERR_MUT_FAIL) 631 replied = 1; 632 } else { 633 ret = KRB5_KDC_UNREACH; 634 } 635 } 636 close (sock); 637 } 638 } 639 640 out: 641 krb5_krbhst_free (context, handle); 642 krb5_auth_con_free (context, auth_context); 643 if (done) 644 return 0; 645 else { 646 if (ret == KRB5_KDC_UNREACH) 647 krb5_set_error_string(context, 648 "unable to reach any changepw server " 649 " in realm %s", realm); 650 return ret; 651 } 652 } 653 654 655 /* 656 * change the password using the credentials in `creds' (for the 657 * principal indicated in them) to `newpw', storing the result of 658 * the operation in `result_*' and an error code or 0. 659 */ 660 661 krb5_error_code 662 krb5_change_password (krb5_context context, 663 krb5_creds *creds, 664 char *newpw, 665 int *result_code, 666 krb5_data *result_code_string, 667 krb5_data *result_string) 668 { 669 struct kpwd_proc *p = find_chpw_proto("change password"); 670 671 *result_code = KRB5_KPASSWD_MALFORMED; 672 result_code_string->data = result_string->data = NULL; 673 result_code_string->length = result_string->length = 0; 674 675 if (p == NULL) 676 return KRB5_KPASSWD_MALFORMED; 677 678 return change_password_loop(context, creds, NULL, newpw, 679 result_code, result_code_string, 680 result_string, p); 681 } 682 683 /* 684 * 685 */ 686 687 krb5_error_code 688 krb5_set_password(krb5_context context, 689 krb5_creds *creds, 690 char *newpw, 691 krb5_principal targprinc, 692 int *result_code, 693 krb5_data *result_code_string, 694 krb5_data *result_string) 695 { 696 krb5_principal principal = NULL; 697 krb5_error_code ret = 0; 698 int i; 699 700 *result_code = KRB5_KPASSWD_MALFORMED; 701 result_code_string->data = result_string->data = NULL; 702 result_code_string->length = result_string->length = 0; 703 704 if (targprinc == NULL) { 705 ret = krb5_get_default_principal(context, &principal); 706 if (ret) 707 return ret; 708 } else 709 principal = targprinc; 710 711 for (i = 0; procs[i].name != NULL; i++) { 712 *result_code = 0; 713 ret = change_password_loop(context, creds, targprinc, newpw, 714 result_code, result_code_string, 715 result_string, 716 &procs[i]); 717 if (ret == 0 && *result_code == 0) 718 break; 719 } 720 721 if (targprinc == NULL) 722 krb5_free_principal(context, principal); 723 return ret; 724 } 725 726 /* 727 * 728 */ 729 730 krb5_error_code 731 krb5_set_password_using_ccache(krb5_context context, 732 krb5_ccache ccache, 733 char *newpw, 734 krb5_principal targprinc, 735 int *result_code, 736 krb5_data *result_code_string, 737 krb5_data *result_string) 738 { 739 krb5_creds creds, *credsp; 740 krb5_error_code ret; 741 krb5_principal principal = NULL; 742 743 *result_code = KRB5_KPASSWD_MALFORMED; 744 result_code_string->data = result_string->data = NULL; 745 result_code_string->length = result_string->length = 0; 746 747 memset(&creds, 0, sizeof(creds)); 748 749 if (targprinc == NULL) { 750 ret = krb5_cc_get_principal(context, ccache, &principal); 751 if (ret) 752 return ret; 753 } else 754 principal = targprinc; 755 756 ret = krb5_make_principal(context, &creds.server, 757 krb5_principal_get_realm(context, principal), 758 "kadmin", "changepw", NULL); 759 if (ret) 760 goto out; 761 762 ret = krb5_cc_get_principal(context, ccache, &creds.client); 763 if (ret) { 764 krb5_free_principal(context, creds.server); 765 goto out; 766 } 767 768 ret = krb5_get_credentials(context, 0, ccache, &creds, &credsp); 769 krb5_free_principal(context, creds.server); 770 krb5_free_principal(context, creds.client); 771 if (ret) 772 goto out; 773 774 ret = krb5_set_password(context, 775 credsp, 776 newpw, 777 principal, 778 result_code, 779 result_code_string, 780 result_string); 781 782 krb5_free_creds(context, credsp); 783 784 return ret; 785 out: 786 if (targprinc == NULL) 787 krb5_free_principal(context, principal); 788 return ret; 789 } 790 791 /* 792 * 793 */ 794 795 const char* 796 krb5_passwd_result_to_string (krb5_context context, 797 int result) 798 { 799 static const char *strings[] = { 800 "Success", 801 "Malformed", 802 "Hard error", 803 "Auth error", 804 "Soft error" , 805 "Access denied", 806 "Bad version", 807 "Initial flag needed" 808 }; 809 810 if (result < 0 || result > KRB5_KPASSWD_INITIAL_FLAG_NEEDED) 811 return "unknown result code"; 812 else 813 return strings[result]; 814 } 815