source4/auth/ntlmssp/ntlmssp_client.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    handle NLTMSSP, client server side parsing
   5
   6    Copyright (C) Andrew Tridgell      2001
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2005
   8    Copyright (C) Stefan Metzmacher 2005
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "auth/ntlmssp/ntlmssp.h"
  26 #include "../lib/crypto/crypto.h"
  27 #include "../libcli/auth/libcli_auth.h"
  28 #include "auth/credentials/credentials.h"
  29 #include "auth/gensec/gensec.h"
  30 #include "param/param.h"
  31 #include "libcli/auth/ntlmssp_private.h"
  32
  33 /*********************************************************************
  34  Client side NTLMSSP
  35 *********************************************************************/
  36
  37 /**
  38  * Next state function for the Initial packet
  39  *
  40  * @param ntlmssp_state NTLMSSP State
  41  * @param out_mem_ctx The DATA_BLOB *out will be allocated on this context
  42  * @param in A NULL data blob (input ignored)
  43  * @param out The initial negotiate request to the server, as an talloc()ed DATA_BLOB, on out_mem_ctx
  44  * @return Errors or NT_STATUS_OK.
  45  */
  46
  47 NTSTATUS ntlmssp_client_initial(struct gensec_security *gensec_security,
  48                                 TALLOC_CTX *out_mem_ctx,
  49                                 DATA_BLOB in, DATA_BLOB *out)
  50 {
  51         struct gensec_ntlmssp_context *gensec_ntlmssp =
  52                 talloc_get_type_abort(gensec_security->private_data,
  53                                       struct gensec_ntlmssp_context);
  54         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
  55         const char *domain = ntlmssp_state->domain;
  56         const char *workstation = cli_credentials_get_workstation(gensec_security->credentials);
  57
  58         /* These don't really matter in the initial packet, so don't panic if they are not set */
  59         if (!domain) {
  60                 domain = "";
  61         }
  62
  63         if (!workstation) {
  64                 workstation = "";
  65         }
  66
  67         if (ntlmssp_state->unicode) {
  68                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_UNICODE;
  69         } else {
  70                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_OEM;
  71         }
  72
  73         if (ntlmssp_state->use_ntlmv2) {
  74                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
  75         }
  76
  77         /* generate the ntlmssp negotiate packet */
  78         msrpc_gen(out_mem_ctx,
  79                   out, "CddAA",
  80                   "NTLMSSP",
  81                   NTLMSSP_NEGOTIATE,
  82                   ntlmssp_state->neg_flags,
  83                   domain,
  84                   workstation);
  85
  86         ntlmssp_state->expected_state = NTLMSSP_CHALLENGE;
  87
  88         return NT_STATUS_MORE_PROCESSING_REQUIRED;
  89 }
  90
  91 /**
  92  * Next state function for the Challenge Packet.  Generate an auth packet.
  93  *
  94  * @param gensec_security GENSEC state
  95  * @param out_mem_ctx Memory context for *out
  96  * @param in The server challnege, as a DATA_BLOB.  reply.data must be NULL
  97  * @param out The next request (auth packet) to the server, as an allocated DATA_BLOB, on the out_mem_ctx context
  98  * @return Errors or NT_STATUS_OK.
  99  */
 100
 101 NTSTATUS ntlmssp_client_challenge(struct gensec_security *gensec_security,
 102                                   TALLOC_CTX *out_mem_ctx,
 103                                   const DATA_BLOB in, DATA_BLOB *out)
 104 {
 105         struct gensec_ntlmssp_context *gensec_ntlmssp =
 106                 talloc_get_type_abort(gensec_security->private_data,
 107                                       struct gensec_ntlmssp_context);
 108         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 109         uint32_t chal_flags, ntlmssp_command, unkn1, unkn2;
 110         DATA_BLOB server_domain_blob;
 111         DATA_BLOB challenge_blob;
 112         DATA_BLOB target_info = data_blob(NULL, 0);
 113         char *server_domain;
 114         const char *chal_parse_string;
 115         const char *auth_gen_string;
 116         DATA_BLOB lm_response = data_blob(NULL, 0);
 117         DATA_BLOB nt_response = data_blob(NULL, 0);
 118         DATA_BLOB session_key = data_blob(NULL, 0);
 119         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 120         DATA_BLOB encrypted_session_key = data_blob(NULL, 0);
 121         NTSTATUS nt_status;
 122         int flags = 0;
 123         const char *user, *domain;
 124
 125         TALLOC_CTX *mem_ctx = talloc_new(out_mem_ctx);
 126         if (!mem_ctx) {
 127                 return NT_STATUS_NO_MEMORY;
 128         }
 129
 130         if (!msrpc_parse(mem_ctx,
 131                          &in, "CdBd",
 132                          "NTLMSSP",
 133                          &ntlmssp_command,
 134                          &server_domain_blob,
 135                          &chal_flags)) {
 136                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#1)\n"));
 137                 dump_data(2, in.data, in.length);
 138                 talloc_free(mem_ctx);
 139
 140                 return NT_STATUS_INVALID_PARAMETER;
 141         }
 142
 143         data_blob_free(&server_domain_blob);
 144
 145         DEBUG(3, ("Got challenge flags:\n"));
 146         debug_ntlmssp_flags(chal_flags);
 147
 148         ntlmssp_handle_neg_flags(ntlmssp_state, chal_flags, ntlmssp_state->allow_lm_key);
 149
 150         if (ntlmssp_state->unicode) {
 151                 if (chal_flags & NTLMSSP_NEGOTIATE_TARGET_INFO) {
 152                         chal_parse_string = "CdUdbddB";
 153                 } else {
 154                         chal_parse_string = "CdUdbdd";
 155                 }
 156                 auth_gen_string = "CdBBUUUBd";
 157         } else {
 158                 if (chal_flags & NTLMSSP_NEGOTIATE_TARGET_INFO) {
 159                         chal_parse_string = "CdAdbddB";
 160                 } else {
 161                         chal_parse_string = "CdAdbdd";
 162                 }
 163
 164                 auth_gen_string = "CdBBAAABd";
 165         }
 166
 167         if (!msrpc_parse(mem_ctx,
 168                          &in, chal_parse_string,
 169                          "NTLMSSP",
 170                          &ntlmssp_command,
 171                          &server_domain,
 172                          &chal_flags,
 173                          &challenge_blob, 8,
 174                          &unkn1, &unkn2,
 175                          &target_info)) {
 176                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#2)\n"));
 177                 dump_data(2, in.data, in.length);
 178                 talloc_free(mem_ctx);
 179                 return NT_STATUS_INVALID_PARAMETER;
 180         }
 181
 182         if (chal_flags & NTLMSSP_TARGET_TYPE_SERVER) {
 183                 ntlmssp_state->server.is_standalone = true;
 184         } else {
 185                 ntlmssp_state->server.is_standalone = false;
 186         }
 187         /* TODO: parse struct_blob and fill in the rest */
 188         ntlmssp_state->server.netbios_name = "";
 189         ntlmssp_state->server.netbios_domain = server_domain;
 190         ntlmssp_state->server.dns_name = "";
 191         ntlmssp_state->server.dns_domain = "";
 192
 193         if (challenge_blob.length != 8) {
 194                 talloc_free(mem_ctx);
 195                 return NT_STATUS_INVALID_PARAMETER;
 196         }
 197
 198         cli_credentials_get_ntlm_username_domain(gensec_security->credentials, mem_ctx,
 199                                                  &user, &domain);
 200
 201         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 202                 flags |= CLI_CRED_NTLM2;
 203         }
 204         if (ntlmssp_state->use_ntlmv2) {
 205                 flags |= CLI_CRED_NTLMv2_AUTH;
 206         }
 207         if (ntlmssp_state->use_nt_response) {
 208                 flags |= CLI_CRED_NTLM_AUTH;
 209         }
 210         if (lpcfg_client_lanman_auth(gensec_security->settings->lp_ctx)) {
 211                 flags |= CLI_CRED_LANMAN_AUTH;
 212         }
 213
 214         nt_status = cli_credentials_get_ntlm_response(gensec_security->credentials, mem_ctx,
 215                                                       &flags, challenge_blob, target_info,
 216                                                       &lm_response, &nt_response,
 217                                                       &lm_session_key, &session_key);
 218
 219         if (!NT_STATUS_IS_OK(nt_status)) {
 220                 return nt_status;
 221         }
 222
 223         if (!(flags & CLI_CRED_LANMAN_AUTH)) {
 224                 /* LM Key is still possible, just silly.  Fortunetly
 225                  * we require command line options to end up here */
 226                 /* ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY; */
 227         }
 228
 229         if (!(flags & CLI_CRED_NTLM2)) {
 230                 /* NTLM2 is incompatible... */
 231                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 232         }
 233
 234         if ((ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 235             && lpcfg_client_lanman_auth(gensec_security->settings->lp_ctx) && lm_session_key.length == 16) {
 236                 DATA_BLOB new_session_key = data_blob_talloc(mem_ctx, NULL, 16);
 237                 if (lm_response.length == 24) {
 238                         SMBsesskeygen_lm_sess_key(lm_session_key.data, lm_response.data,
 239                                                   new_session_key.data);
 240                 } else {
 241                         static const uint8_t zeros[24];
 242                         SMBsesskeygen_lm_sess_key(lm_session_key.data, zeros,
 243                                                   new_session_key.data);
 244                 }
 245                 session_key = new_session_key;
 246                 dump_data_pw("LM session key\n", session_key.data, session_key.length);
 247         }
 248
 249
 250         /* Key exchange encryptes a new client-generated session key with
 251            the password-derived key */
 252         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 253                 /* Make up a new session key */
 254                 uint8_t client_session_key[16];
 255                 generate_secret_buffer(client_session_key, sizeof(client_session_key));
 256
 257                 /* Encrypt the new session key with the old one */
 258                 encrypted_session_key = data_blob_talloc(ntlmssp_state,
 259                                                          client_session_key, sizeof(client_session_key));
 260                 dump_data_pw("KEY_EXCH session key:\n", encrypted_session_key.data, encrypted_session_key.length);
 261                 arcfour_crypt(encrypted_session_key.data, session_key.data, encrypted_session_key.length);
 262                 dump_data_pw("KEY_EXCH session key (enc):\n", encrypted_session_key.data, encrypted_session_key.length);
 263
 264                 /* Mark the new session key as the 'real' session key */
 265                 session_key = data_blob_talloc(mem_ctx, client_session_key, sizeof(client_session_key));
 266         }
 267
 268         DEBUG(3, ("NTLMSSP: Set final flags:\n"));
 269         debug_ntlmssp_flags(ntlmssp_state->neg_flags);
 270
 271         /* this generates the actual auth packet */
 272         if (!msrpc_gen(mem_ctx,
 273                        out, auth_gen_string,
 274                        "NTLMSSP",
 275                        NTLMSSP_AUTH,
 276                        lm_response.data, lm_response.length,
 277                        nt_response.data, nt_response.length,
 278                        domain,
 279                        user,
 280                        cli_credentials_get_workstation(gensec_security->credentials),
 281                        encrypted_session_key.data, encrypted_session_key.length,
 282                        ntlmssp_state->neg_flags)) {
 283                 talloc_free(mem_ctx);
 284                 return NT_STATUS_NO_MEMORY;
 285         }
 286
 287         ntlmssp_state->session_key = session_key;
 288         talloc_steal(ntlmssp_state, session_key.data);
 289
 290         talloc_steal(out_mem_ctx, out->data);
 291
 292         ntlmssp_state->chal = challenge_blob;
 293         ntlmssp_state->lm_resp = lm_response;
 294         talloc_steal(ntlmssp_state->lm_resp.data, lm_response.data);
 295         ntlmssp_state->nt_resp = nt_response;
 296         talloc_steal(ntlmssp_state->nt_resp.data, nt_response.data);
 297
 298         ntlmssp_state->expected_state = NTLMSSP_DONE;
 299
 300         if (gensec_security->want_features & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL)) {
 301                 nt_status = ntlmssp_sign_init(ntlmssp_state);
 302                 if (!NT_STATUS_IS_OK(nt_status)) {
 303                         DEBUG(1, ("Could not setup NTLMSSP signing/sealing system (error was: %s)\n",
 304                                   nt_errstr(nt_status)));
 305                         talloc_free(mem_ctx);
 306                         return nt_status;
 307                 }
 308         }
 309
 310         talloc_free(mem_ctx);
 311         return NT_STATUS_OK;
 312 }
 313
 314 NTSTATUS gensec_ntlmssp_client_start(struct gensec_security *gensec_security)
 315 {
 316         struct gensec_ntlmssp_context *gensec_ntlmssp;
 317         struct ntlmssp_state *ntlmssp_state;
 318         NTSTATUS nt_status;
 319
 320         nt_status = gensec_ntlmssp_start(gensec_security);
 321         NT_STATUS_NOT_OK_RETURN(nt_status);
 322
 323         gensec_ntlmssp = talloc_get_type_abort(gensec_security->private_data,
 324                                                struct gensec_ntlmssp_context);
 325         ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 326
 327         ntlmssp_state->role = NTLMSSP_CLIENT;
 328
 329         ntlmssp_state->domain = lpcfg_workgroup(gensec_security->settings->lp_ctx);
 330
 331         ntlmssp_state->unicode = gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "unicode", true);
 332
 333         ntlmssp_state->use_nt_response = gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "send_nt_reponse", true);
 334
 335         ntlmssp_state->allow_lm_key = (lpcfg_client_lanman_auth(gensec_security->settings->lp_ctx)
 336                                               && (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "allow_lm_key", false)
 337                                                   || gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "lm_key", false)));
 338
 339         ntlmssp_state->use_ntlmv2 = lpcfg_client_ntlmv2_auth(gensec_security->settings->lp_ctx);
 340
 341         ntlmssp_state->expected_state = NTLMSSP_INITIAL;
 342
 343         ntlmssp_state->neg_flags =
 344                 NTLMSSP_NEGOTIATE_NTLM |
 345                 NTLMSSP_REQUEST_TARGET;
 346
 347         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "128bit", true)) {
 348                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 349         }
 350
 351         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "56bit", false)) {
 352                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 353         }
 354
 355         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "lm_key", false)) {
 356                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_LM_KEY;
 357         }
 358
 359         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "keyexchange", true)) {
 360                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 361         }
 362
 363         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "alwayssign", true)) {
 364                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 365         }
 366
 367         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "ntlm2", true)) {
 368                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 369         } else {
 370                 /* apparently we can't do ntlmv2 if we don't do ntlm2 */
 371                 ntlmssp_state->use_ntlmv2 = false;
 372         }
 373
 374         if (gensec_security->want_features & GENSEC_FEATURE_SESSION_KEY) {
 375                 /*
 376                  * We need to set this to allow a later SetPassword
 377                  * via the SAMR pipe to succeed. Strange.... We could
 378                  * also add  NTLMSSP_NEGOTIATE_SEAL here. JRA.
 379                  *
 380                  * Without this, Windows will not create the master key
 381                  * that it thinks is only used for NTLMSSP signing and
 382                  * sealing.  (It is actually pulled out and used directly)
 383                  */
 384                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 385         }
 386         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 387                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 388         }
 389         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 390                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 391                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 392         }
 393
 394         return NT_STATUS_OK;
 395 }
 396