source/libsmb/clispnego.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    simple kerberos5/SPNEGO routines
   4    Copyright (C) Andrew Tridgell 2001
   5    Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2002
   6    Copyright (C) Luke Howard     2003
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24
  25 /*
  26   generate a negTokenInit packet given a GUID, a list of supported
  27   OIDs (the mechanisms) and a principal name string
  28 */
  29 DATA_BLOB spnego_gen_negTokenInit(char guid[16],
  30                                   const char *OIDs[],
  31                                   const char *principal)
  32 {
  33         int i;
  34         ASN1_DATA data;
  35         DATA_BLOB ret;
  36
  37         memset(&data, 0, sizeof(data));
  38
  39         asn1_write(&data, guid, 16);
  40         asn1_push_tag(&data,ASN1_APPLICATION(0));
  41         asn1_write_OID(&data,OID_SPNEGO);
  42         asn1_push_tag(&data,ASN1_CONTEXT(0));
  43         asn1_push_tag(&data,ASN1_SEQUENCE(0));
  44
  45         asn1_push_tag(&data,ASN1_CONTEXT(0));
  46         asn1_push_tag(&data,ASN1_SEQUENCE(0));
  47         for (i=0; OIDs[i]; i++) {
  48                 asn1_write_OID(&data,OIDs[i]);
  49         }
  50         asn1_pop_tag(&data);
  51         asn1_pop_tag(&data);
  52
  53         asn1_push_tag(&data, ASN1_CONTEXT(3));
  54         asn1_push_tag(&data, ASN1_SEQUENCE(0));
  55         asn1_push_tag(&data, ASN1_CONTEXT(0));
  56         asn1_write_GeneralString(&data,principal);
  57         asn1_pop_tag(&data);
  58         asn1_pop_tag(&data);
  59         asn1_pop_tag(&data);
  60
  61         asn1_pop_tag(&data);
  62         asn1_pop_tag(&data);
  63
  64         asn1_pop_tag(&data);
  65
  66         if (data.has_error) {
  67                 DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data.ofs));
  68                 asn1_free(&data);
  69         }
  70
  71         ret = data_blob(data.data, data.length);
  72         asn1_free(&data);
  73
  74         return ret;
  75 }
  76
  77 /*
  78   Generate a negTokenInit as used by the client side ... It has a mechType
  79   (OID), and a mechToken (a security blob) ...
  80
  81   Really, we need to break out the NTLMSSP stuff as well, because it could be
  82   raw in the packets!
  83 */
  84 DATA_BLOB gen_negTokenInit(const char *OID, DATA_BLOB blob)
  85 {
  86         ASN1_DATA data;
  87         DATA_BLOB ret;
  88
  89         memset(&data, 0, sizeof(data));
  90
  91         asn1_push_tag(&data, ASN1_APPLICATION(0));
  92         asn1_write_OID(&data,OID_SPNEGO);
  93         asn1_push_tag(&data, ASN1_CONTEXT(0));
  94         asn1_push_tag(&data, ASN1_SEQUENCE(0));
  95
  96         asn1_push_tag(&data, ASN1_CONTEXT(0));
  97         asn1_push_tag(&data, ASN1_SEQUENCE(0));
  98         asn1_write_OID(&data, OID);
  99         asn1_pop_tag(&data);
 100         asn1_pop_tag(&data);
 101
 102         asn1_push_tag(&data, ASN1_CONTEXT(2));
 103         asn1_write_OctetString(&data,blob.data,blob.length);
 104         asn1_pop_tag(&data);
 105
 106         asn1_pop_tag(&data);
 107         asn1_pop_tag(&data);
 108
 109         asn1_pop_tag(&data);
 110
 111         if (data.has_error) {
 112                 DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data.ofs));
 113                 asn1_free(&data);
 114         }
 115
 116         ret = data_blob(data.data, data.length);
 117         asn1_free(&data);
 118
 119         return ret;
 120 }
 121
 122 /*
 123   parse a negTokenInit packet giving a GUID, a list of supported
 124   OIDs (the mechanisms) and a principal name string
 125 */
 126 BOOL spnego_parse_negTokenInit(DATA_BLOB blob,
 127                                char *OIDs[ASN1_MAX_OIDS],
 128                                char **principal)
 129 {
 130         int i;
 131         BOOL ret;
 132         ASN1_DATA data;
 133
 134         asn1_load(&data, blob);
 135
 136         asn1_start_tag(&data,ASN1_APPLICATION(0));
 137         asn1_check_OID(&data,OID_SPNEGO);
 138         asn1_start_tag(&data,ASN1_CONTEXT(0));
 139         asn1_start_tag(&data,ASN1_SEQUENCE(0));
 140
 141         asn1_start_tag(&data,ASN1_CONTEXT(0));
 142         asn1_start_tag(&data,ASN1_SEQUENCE(0));
 143         for (i=0; asn1_tag_remaining(&data) > 0 && i < ASN1_MAX_OIDS; i++) {
 144                 char *oid_str = NULL;
 145                 asn1_read_OID(&data,&oid_str);
 146                 OIDs[i] = oid_str;
 147         }
 148         OIDs[i] = NULL;
 149         asn1_end_tag(&data);
 150         asn1_end_tag(&data);
 151
 152         asn1_start_tag(&data, ASN1_CONTEXT(3));
 153         asn1_start_tag(&data, ASN1_SEQUENCE(0));
 154         asn1_start_tag(&data, ASN1_CONTEXT(0));
 155         asn1_read_GeneralString(&data,principal);
 156         asn1_end_tag(&data);
 157         asn1_end_tag(&data);
 158         asn1_end_tag(&data);
 159
 160         asn1_end_tag(&data);
 161         asn1_end_tag(&data);
 162
 163         asn1_end_tag(&data);
 164
 165         ret = !data.has_error;
 166         asn1_free(&data);
 167         return ret;
 168 }
 169
 170
 171 /*
 172   generate a negTokenTarg packet given a list of OIDs and a security blob
 173 */
 174 DATA_BLOB gen_negTokenTarg(const char *OIDs[], DATA_BLOB blob)
 175 {
 176         int i;
 177         ASN1_DATA data;
 178         DATA_BLOB ret;
 179
 180         memset(&data, 0, sizeof(data));
 181
 182         asn1_push_tag(&data, ASN1_APPLICATION(0));
 183         asn1_write_OID(&data,OID_SPNEGO);
 184         asn1_push_tag(&data, ASN1_CONTEXT(0));
 185         asn1_push_tag(&data, ASN1_SEQUENCE(0));
 186
 187         asn1_push_tag(&data, ASN1_CONTEXT(0));
 188         asn1_push_tag(&data, ASN1_SEQUENCE(0));
 189         for (i=0; OIDs[i]; i++) {
 190                 asn1_write_OID(&data,OIDs[i]);
 191         }
 192         asn1_pop_tag(&data);
 193         asn1_pop_tag(&data);
 194
 195         asn1_push_tag(&data, ASN1_CONTEXT(2));
 196         asn1_write_OctetString(&data,blob.data,blob.length);
 197         asn1_pop_tag(&data);
 198
 199         asn1_pop_tag(&data);
 200         asn1_pop_tag(&data);
 201
 202         asn1_pop_tag(&data);
 203
 204         if (data.has_error) {
 205                 DEBUG(1,("Failed to build negTokenTarg at offset %d\n", (int)data.ofs));
 206                 asn1_free(&data);
 207         }
 208
 209         ret = data_blob(data.data, data.length);
 210         asn1_free(&data);
 211
 212         return ret;
 213 }
 214
 215
 216 /*
 217   parse a negTokenTarg packet giving a list of OIDs and a security blob
 218 */
 219 BOOL parse_negTokenTarg(DATA_BLOB blob, char *OIDs[ASN1_MAX_OIDS], DATA_BLOB *secblob)
 220 {
 221         int i;
 222         ASN1_DATA data;
 223
 224         asn1_load(&data, blob);
 225         asn1_start_tag(&data, ASN1_APPLICATION(0));
 226         asn1_check_OID(&data,OID_SPNEGO);
 227         asn1_start_tag(&data, ASN1_CONTEXT(0));
 228         asn1_start_tag(&data, ASN1_SEQUENCE(0));
 229
 230         asn1_start_tag(&data, ASN1_CONTEXT(0));
 231         asn1_start_tag(&data, ASN1_SEQUENCE(0));
 232         for (i=0; asn1_tag_remaining(&data) > 0 && i < ASN1_MAX_OIDS; i++) {
 233                 char *oid_str = NULL;
 234                 asn1_read_OID(&data,&oid_str);
 235                 OIDs[i] = oid_str;
 236         }
 237         OIDs[i] = NULL;
 238         asn1_end_tag(&data);
 239         asn1_end_tag(&data);
 240
 241         asn1_start_tag(&data, ASN1_CONTEXT(2));
 242         asn1_read_OctetString(&data,secblob);
 243         asn1_end_tag(&data);
 244
 245         asn1_end_tag(&data);
 246         asn1_end_tag(&data);
 247
 248         asn1_end_tag(&data);
 249
 250         if (data.has_error) {
 251                 DEBUG(1,("Failed to parse negTokenTarg at offset %d\n", (int)data.ofs));
 252                 asn1_free(&data);
 253                 return False;
 254         }
 255
 256         asn1_free(&data);
 257         return True;
 258 }
 259
 260 /*
 261   generate a krb5 GSS-API wrapper packet given a ticket
 262 */
 263 DATA_BLOB spnego_gen_krb5_wrap(DATA_BLOB ticket, const uint8 tok_id[2])
 264 {
 265         ASN1_DATA data;
 266         DATA_BLOB ret;
 267
 268         memset(&data, 0, sizeof(data));
 269
 270         asn1_push_tag(&data, ASN1_APPLICATION(0));
 271         asn1_write_OID(&data, OID_KERBEROS5);
 272
 273         asn1_write(&data, tok_id, 2);
 274         asn1_write(&data, ticket.data, ticket.length);
 275         asn1_pop_tag(&data);
 276
 277         if (data.has_error) {
 278                 DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data.ofs));
 279                 asn1_free(&data);
 280         }
 281
 282         ret = data_blob(data.data, data.length);
 283         asn1_free(&data);
 284
 285         return ret;
 286 }
 287
 288 /*
 289   parse a krb5 GSS-API wrapper packet giving a ticket
 290 */
 291 BOOL spnego_parse_krb5_wrap(DATA_BLOB blob, DATA_BLOB *ticket, uint8 tok_id[2])
 292 {
 293         BOOL ret;
 294         ASN1_DATA data;
 295         int data_remaining;
 296
 297         asn1_load(&data, blob);
 298         asn1_start_tag(&data, ASN1_APPLICATION(0));
 299         asn1_check_OID(&data, OID_KERBEROS5);
 300
 301         data_remaining = asn1_tag_remaining(&data);
 302
 303         if (data_remaining < 3) {
 304                 data.has_error = True;
 305         } else {
 306                 asn1_read(&data, tok_id, 2);
 307                 data_remaining -= 2;
 308                 *ticket = data_blob(NULL, data_remaining);
 309                 asn1_read(&data, ticket->data, ticket->length);
 310         }
 311
 312         asn1_end_tag(&data);
 313
 314         ret = !data.has_error;
 315
 316         asn1_free(&data);
 317
 318         return ret;
 319 }
 320
 321
 322 /*
 323    generate a SPNEGO negTokenTarg packet, ready for a EXTENDED_SECURITY
 324    kerberos session setup
 325 */
 326 int spnego_gen_negTokenTarg(const char *principal, int time_offset,
 327                             DATA_BLOB *targ,
 328                             DATA_BLOB *session_key_krb5, uint32 extra_ap_opts)
 329 {
 330         int retval;
 331         DATA_BLOB tkt, tkt_wrapped;
 332         const char *krb_mechs[] = {OID_KERBEROS5_OLD, OID_NTLMSSP, NULL};
 333
 334         /* get a kerberos ticket for the service and extract the session key */
 335         retval = cli_krb5_get_ticket(principal, time_offset,
 336                                         &tkt, session_key_krb5, extra_ap_opts);
 337
 338         if (retval)
 339                 return retval;
 340
 341         /* wrap that up in a nice GSS-API wrapping */
 342         tkt_wrapped = spnego_gen_krb5_wrap(tkt, TOK_ID_KRB_AP_REQ);
 343
 344         /* and wrap that in a shiny SPNEGO wrapper */
 345         *targ = gen_negTokenTarg(krb_mechs, tkt_wrapped);
 346
 347         data_blob_free(&tkt_wrapped);
 348         data_blob_free(&tkt);
 349
 350         return retval;
 351 }
 352
 353
 354 /*
 355   parse a spnego NTLMSSP challenge packet giving two security blobs
 356 */
 357 BOOL spnego_parse_challenge(const DATA_BLOB blob,
 358                             DATA_BLOB *chal1, DATA_BLOB *chal2)
 359 {
 360         BOOL ret;
 361         ASN1_DATA data;
 362
 363         ZERO_STRUCTP(chal1);
 364         ZERO_STRUCTP(chal2);
 365
 366         asn1_load(&data, blob);
 367         asn1_start_tag(&data,ASN1_CONTEXT(1));
 368         asn1_start_tag(&data,ASN1_SEQUENCE(0));
 369
 370         asn1_start_tag(&data,ASN1_CONTEXT(0));
 371         asn1_check_enumerated(&data,1);
 372         asn1_end_tag(&data);
 373
 374         asn1_start_tag(&data,ASN1_CONTEXT(1));
 375         asn1_check_OID(&data, OID_NTLMSSP);
 376         asn1_end_tag(&data);
 377
 378         asn1_start_tag(&data,ASN1_CONTEXT(2));
 379         asn1_read_OctetString(&data, chal1);
 380         asn1_end_tag(&data);
 381
 382         /* the second challenge is optional (XP doesn't send it) */
 383         if (asn1_tag_remaining(&data)) {
 384                 asn1_start_tag(&data,ASN1_CONTEXT(3));
 385                 asn1_read_OctetString(&data, chal2);
 386                 asn1_end_tag(&data);
 387         }
 388
 389         asn1_end_tag(&data);
 390         asn1_end_tag(&data);
 391
 392         ret = !data.has_error;
 393         asn1_free(&data);
 394         return ret;
 395 }
 396
 397
 398 /*
 399  generate a SPNEGO auth packet. This will contain the encrypted passwords
 400 */
 401 DATA_BLOB spnego_gen_auth(DATA_BLOB blob)
 402 {
 403         ASN1_DATA data;
 404         DATA_BLOB ret;
 405
 406         memset(&data, 0, sizeof(data));
 407
 408         asn1_push_tag(&data, ASN1_CONTEXT(1));
 409         asn1_push_tag(&data, ASN1_SEQUENCE(0));
 410         asn1_push_tag(&data, ASN1_CONTEXT(2));
 411         asn1_write_OctetString(&data,blob.data,blob.length);
 412         asn1_pop_tag(&data);
 413         asn1_pop_tag(&data);
 414         asn1_pop_tag(&data);
 415
 416         ret = data_blob(data.data, data.length);
 417
 418         asn1_free(&data);
 419
 420         return ret;
 421 }
 422
 423 /*
 424  parse a SPNEGO auth packet. This contains the encrypted passwords
 425 */
 426 BOOL spnego_parse_auth(DATA_BLOB blob, DATA_BLOB *auth)
 427 {
 428         ASN1_DATA data;
 429
 430         asn1_load(&data, blob);
 431         asn1_start_tag(&data, ASN1_CONTEXT(1));
 432         asn1_start_tag(&data, ASN1_SEQUENCE(0));
 433         asn1_start_tag(&data, ASN1_CONTEXT(2));
 434         asn1_read_OctetString(&data,auth);
 435         asn1_end_tag(&data);
 436         asn1_end_tag(&data);
 437         asn1_end_tag(&data);
 438
 439         if (data.has_error) {
 440                 DEBUG(3,("spnego_parse_auth failed at %d\n", (int)data.ofs));
 441                 asn1_free(&data);
 442                 return False;
 443         }
 444
 445         asn1_free(&data);
 446         return True;
 447 }
 448
 449 /*
 450   generate a minimal SPNEGO response packet.  Doesn't contain much.
 451 */
 452 DATA_BLOB spnego_gen_auth_response(DATA_BLOB *reply, NTSTATUS nt_status,
 453                                    const char *mechOID)
 454 {
 455         ASN1_DATA data;
 456         DATA_BLOB ret;
 457         uint8 negResult;
 458
 459         if (NT_STATUS_IS_OK(nt_status)) {
 460                 negResult = SPNEGO_NEG_RESULT_ACCEPT;
 461         } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 462                 negResult = SPNEGO_NEG_RESULT_INCOMPLETE;
 463         } else {
 464                 negResult = SPNEGO_NEG_RESULT_REJECT;
 465         }
 466
 467         ZERO_STRUCT(data);
 468
 469         asn1_push_tag(&data, ASN1_CONTEXT(1));
 470         asn1_push_tag(&data, ASN1_SEQUENCE(0));
 471         asn1_push_tag(&data, ASN1_CONTEXT(0));
 472         asn1_write_enumerated(&data, negResult);
 473         asn1_pop_tag(&data);
 474
 475         if (reply->data != NULL) {
 476                 asn1_push_tag(&data,ASN1_CONTEXT(1));
 477                 asn1_write_OID(&data, mechOID);
 478                 asn1_pop_tag(&data);
 479
 480                 asn1_push_tag(&data,ASN1_CONTEXT(2));
 481                 asn1_write_OctetString(&data, reply->data, reply->length);
 482                 asn1_pop_tag(&data);
 483         }
 484
 485         asn1_pop_tag(&data);
 486         asn1_pop_tag(&data);
 487
 488         ret = data_blob(data.data, data.length);
 489         asn1_free(&data);
 490         return ret;
 491 }
 492
 493 /*
 494  parse a SPNEGO NTLMSSP auth packet. This contains the encrypted passwords
 495 */
 496 BOOL spnego_parse_auth_response(DATA_BLOB blob, NTSTATUS nt_status,
 497                                 DATA_BLOB *auth)
 498 {
 499         ASN1_DATA data;
 500         uint8 negResult;
 501
 502         if (NT_STATUS_IS_OK(nt_status)) {
 503                 negResult = SPNEGO_NEG_RESULT_ACCEPT;
 504         } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 505                 negResult = SPNEGO_NEG_RESULT_INCOMPLETE;
 506         } else {
 507                 negResult = SPNEGO_NEG_RESULT_REJECT;
 508         }
 509
 510         asn1_load(&data, blob);
 511         asn1_start_tag(&data, ASN1_CONTEXT(1));
 512         asn1_start_tag(&data, ASN1_SEQUENCE(0));
 513         asn1_start_tag(&data, ASN1_CONTEXT(0));
 514         asn1_check_enumerated(&data, negResult);
 515         asn1_end_tag(&data);
 516
 517         if (negResult == SPNEGO_NEG_RESULT_INCOMPLETE) {
 518                 asn1_start_tag(&data,ASN1_CONTEXT(1));
 519                 asn1_check_OID(&data, OID_NTLMSSP);
 520                 asn1_end_tag(&data);
 521
 522                 asn1_start_tag(&data,ASN1_CONTEXT(2));
 523                 asn1_read_OctetString(&data, auth);
 524                 asn1_end_tag(&data);
 525         }
 526
 527         asn1_end_tag(&data);
 528         asn1_end_tag(&data);
 529
 530         if (data.has_error) {
 531                 DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data.ofs));
 532                 asn1_free(&data);
 533                 data_blob_free(auth);
 534                 return False;
 535         }
 536
 537         asn1_free(&data);
 538         return True;
 539 }
 540