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 "auth/ntlmssp/msrpc_parse.h"
  27 #include "../lib/crypto/crypto.h"
  28 #include "libcli/auth/libcli_auth.h"
  29 #include "auth/credentials/credentials.h"
  30 #include "auth/gensec/gensec.h"
  31 #include "param/param.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_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
  52         const char *domain = gensec_ntlmssp_state->domain;
  53         const char *workstation = cli_credentials_get_workstation(gensec_security->credentials);
  54
  55         /* These don't really matter in the initial packet, so don't panic if they are not set */
  56         if (!domain) {
  57                 domain = "";
  58         }
  59
  60         if (!workstation) {
  61                 workstation = "";
  62         }
  63
  64         if (gensec_ntlmssp_state->unicode) {
  65                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_UNICODE;
  66         } else {
  67                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_OEM;
  68         }
  69
  70         if (gensec_ntlmssp_state->use_ntlmv2) {
  71                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
  72         }
  73
  74         /* generate the ntlmssp negotiate packet */
  75         msrpc_gen(out_mem_ctx,
  76                   out, "CddAA",
  77                   "NTLMSSP",
  78                   NTLMSSP_NEGOTIATE,
  79                   gensec_ntlmssp_state->neg_flags,
  80                   domain,
  81                   workstation);
  82
  83         gensec_ntlmssp_state->expected_state = NTLMSSP_CHALLENGE;
  84
  85         return NT_STATUS_MORE_PROCESSING_REQUIRED;
  86 }
  87
  88 /**
  89  * Next state function for the Challenge Packet.  Generate an auth packet.
  90  *
  91  * @param gensec_security GENSEC state
  92  * @param out_mem_ctx Memory context for *out
  93  * @param in The server challnege, as a DATA_BLOB.  reply.data must be NULL
  94  * @param out The next request (auth packet) to the server, as an allocated DATA_BLOB, on the out_mem_ctx context
  95  * @return Errors or NT_STATUS_OK.
  96  */
  97
  98 NTSTATUS ntlmssp_client_challenge(struct gensec_security *gensec_security,
  99                                   TALLOC_CTX *out_mem_ctx,
 100                                   const DATA_BLOB in, DATA_BLOB *out)
 101 {
 102         struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
 103         uint32_t chal_flags, ntlmssp_command, unkn1, unkn2;
 104         DATA_BLOB server_domain_blob;
 105         DATA_BLOB challenge_blob;
 106         DATA_BLOB target_info = data_blob(NULL, 0);
 107         char *server_domain;
 108         const char *chal_parse_string;
 109         const char *auth_gen_string;
 110         DATA_BLOB lm_response = data_blob(NULL, 0);
 111         DATA_BLOB nt_response = data_blob(NULL, 0);
 112         DATA_BLOB session_key = data_blob(NULL, 0);
 113         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 114         DATA_BLOB encrypted_session_key = data_blob(NULL, 0);
 115         NTSTATUS nt_status;
 116         int flags = 0;
 117         const char *user, *domain;
 118
 119         TALLOC_CTX *mem_ctx = talloc_new(out_mem_ctx);
 120         if (!mem_ctx) {
 121                 return NT_STATUS_NO_MEMORY;
 122         }
 123
 124         if (!msrpc_parse(mem_ctx,
 125                          lp_iconv_convenience(gensec_security->lp_ctx),
 126                          &in, "CdBd",
 127                          "NTLMSSP",
 128                          &ntlmssp_command,
 129                          &server_domain_blob,
 130                          &chal_flags)) {
 131                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#1)\n"));
 132                 dump_data(2, in.data, in.length);
 133                 talloc_free(mem_ctx);
 134
 135                 return NT_STATUS_INVALID_PARAMETER;
 136         }
 137
 138         data_blob_free(&server_domain_blob);
 139
 140         DEBUG(3, ("Got challenge flags:\n"));
 141         debug_ntlmssp_flags(chal_flags);
 142
 143         ntlmssp_handle_neg_flags(gensec_ntlmssp_state, chal_flags, gensec_ntlmssp_state->allow_lm_key);
 144
 145         if (gensec_ntlmssp_state->unicode) {
 146                 if (chal_flags & NTLMSSP_CHAL_TARGET_INFO) {
 147                         chal_parse_string = "CdUdbddB";
 148                 } else {
 149                         chal_parse_string = "CdUdbdd";
 150                 }
 151                 auth_gen_string = "CdBBUUUBd";
 152         } else {
 153                 if (chal_flags & NTLMSSP_CHAL_TARGET_INFO) {
 154                         chal_parse_string = "CdAdbddB";
 155                 } else {
 156                         chal_parse_string = "CdAdbdd";
 157                 }
 158
 159                 auth_gen_string = "CdBBAAABd";
 160         }
 161
 162         if (!msrpc_parse(mem_ctx,
 163                          lp_iconv_convenience(gensec_security->lp_ctx),
 164                          &in, chal_parse_string,
 165                          "NTLMSSP",
 166                          &ntlmssp_command,
 167                          &server_domain,
 168                          &chal_flags,
 169                          &challenge_blob, 8,
 170                          &unkn1, &unkn2,
 171                          &target_info)) {
 172                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#2)\n"));
 173                 dump_data(2, in.data, in.length);
 174                 talloc_free(mem_ctx);
 175                 return NT_STATUS_INVALID_PARAMETER;
 176         }
 177
 178         gensec_ntlmssp_state->server_domain = server_domain;
 179
 180         if (challenge_blob.length != 8) {
 181                 talloc_free(mem_ctx);
 182                 return NT_STATUS_INVALID_PARAMETER;
 183         }
 184
 185         cli_credentials_get_ntlm_username_domain(gensec_security->credentials, mem_ctx,
 186                                                  &user, &domain);
 187
 188         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 189                 flags |= CLI_CRED_NTLM2;
 190         }
 191         if (gensec_ntlmssp_state->use_ntlmv2) {
 192                 flags |= CLI_CRED_NTLMv2_AUTH;
 193         }
 194         if (gensec_ntlmssp_state->use_nt_response) {
 195                 flags |= CLI_CRED_NTLM_AUTH;
 196         }
 197         if (lp_client_lanman_auth(gensec_security->lp_ctx)) {
 198                 flags |= CLI_CRED_LANMAN_AUTH;
 199         }
 200
 201         nt_status = cli_credentials_get_ntlm_response(gensec_security->credentials, mem_ctx,
 202                                                       &flags, challenge_blob, target_info,
 203                                                       &lm_response, &nt_response,
 204                                                       &lm_session_key, &session_key);
 205
 206         if (!NT_STATUS_IS_OK(nt_status)) {
 207                 return nt_status;
 208         }
 209
 210         if (!(flags & CLI_CRED_LANMAN_AUTH)) {
 211                 /* LM Key is still possible, just silly.  Fortunetly
 212                  * we require command line options to end up here */
 213                 /* gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY; */
 214         }
 215
 216         if (!(flags & CLI_CRED_NTLM2)) {
 217                 /* NTLM2 is incompatible... */
 218                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 219         }
 220
 221         if ((gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 222             && lp_client_lanman_auth(gensec_security->lp_ctx) && lm_session_key.length == 16) {
 223                 DATA_BLOB new_session_key = data_blob_talloc(mem_ctx, NULL, 16);
 224                 if (lm_response.length == 24) {
 225                         SMBsesskeygen_lm_sess_key(lm_session_key.data, lm_response.data,
 226                                                   new_session_key.data);
 227                 } else {
 228                         static const uint8_t zeros[24];
 229                         SMBsesskeygen_lm_sess_key(lm_session_key.data, zeros,
 230                                                   new_session_key.data);
 231                 }
 232                 session_key = new_session_key;
 233                 dump_data_pw("LM session key\n", session_key.data, session_key.length);
 234         }
 235
 236
 237         /* Key exchange encryptes a new client-generated session key with
 238            the password-derived key */
 239         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 240                 /* Make up a new session key */
 241                 uint8_t client_session_key[16];
 242                 generate_secret_buffer(client_session_key, sizeof(client_session_key));
 243
 244                 /* Encrypt the new session key with the old one */
 245                 encrypted_session_key = data_blob_talloc(gensec_ntlmssp_state,
 246                                                          client_session_key, sizeof(client_session_key));
 247                 dump_data_pw("KEY_EXCH session key:\n", encrypted_session_key.data, encrypted_session_key.length);
 248                 arcfour_crypt(encrypted_session_key.data, session_key.data, encrypted_session_key.length);
 249                 dump_data_pw("KEY_EXCH session key (enc):\n", encrypted_session_key.data, encrypted_session_key.length);
 250
 251                 /* Mark the new session key as the 'real' session key */
 252                 session_key = data_blob_talloc(mem_ctx, client_session_key, sizeof(client_session_key));
 253         }
 254
 255         DEBUG(3, ("NTLMSSP: Set final flags:\n"));
 256         debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
 257
 258         /* this generates the actual auth packet */
 259         if (!msrpc_gen(mem_ctx,
 260                        out, auth_gen_string,
 261                        "NTLMSSP",
 262                        NTLMSSP_AUTH,
 263                        lm_response.data, lm_response.length,
 264                        nt_response.data, nt_response.length,
 265                        domain,
 266                        user,
 267                        cli_credentials_get_workstation(gensec_security->credentials),
 268                        encrypted_session_key.data, encrypted_session_key.length,
 269                        gensec_ntlmssp_state->neg_flags)) {
 270                 talloc_free(mem_ctx);
 271                 return NT_STATUS_NO_MEMORY;
 272         }
 273
 274         gensec_ntlmssp_state->session_key = session_key;
 275         talloc_steal(gensec_ntlmssp_state, session_key.data);
 276
 277         talloc_steal(out_mem_ctx, out->data);
 278
 279         gensec_ntlmssp_state->chal = challenge_blob;
 280         gensec_ntlmssp_state->lm_resp = lm_response;
 281         talloc_steal(gensec_ntlmssp_state->lm_resp.data, lm_response.data);
 282         gensec_ntlmssp_state->nt_resp = nt_response;
 283         talloc_steal(gensec_ntlmssp_state->nt_resp.data, nt_response.data);
 284
 285         gensec_ntlmssp_state->expected_state = NTLMSSP_DONE;
 286
 287         if (gensec_security->want_features & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL)) {
 288                 nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
 289                 if (!NT_STATUS_IS_OK(nt_status)) {
 290                         DEBUG(1, ("Could not setup NTLMSSP signing/sealing system (error was: %s)\n",
 291                                   nt_errstr(nt_status)));
 292                         talloc_free(mem_ctx);
 293                         return nt_status;
 294                 }
 295         }
 296
 297         talloc_free(mem_ctx);
 298         return NT_STATUS_OK;
 299 }
 300
 301 NTSTATUS gensec_ntlmssp_client_start(struct gensec_security *gensec_security)
 302 {
 303         struct gensec_ntlmssp_state *gensec_ntlmssp_state;
 304         NTSTATUS nt_status;
 305
 306         nt_status = gensec_ntlmssp_start(gensec_security);
 307         NT_STATUS_NOT_OK_RETURN(nt_status);
 308
 309         gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
 310
 311         gensec_ntlmssp_state->role = NTLMSSP_CLIENT;
 312
 313         gensec_ntlmssp_state->domain = lp_workgroup(gensec_security->lp_ctx);
 314
 315         gensec_ntlmssp_state->unicode = lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "unicode", true);
 316
 317         gensec_ntlmssp_state->use_nt_response = lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "send_nt_reponse", true);
 318
 319         gensec_ntlmssp_state->allow_lm_key = (lp_client_lanman_auth(gensec_security->lp_ctx)
 320                                               && (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "allow_lm_key", false)
 321                                                   || lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "lm_key", false)));
 322
 323         gensec_ntlmssp_state->use_ntlmv2 = lp_client_ntlmv2_auth(gensec_security->lp_ctx);
 324
 325         gensec_ntlmssp_state->expected_state = NTLMSSP_INITIAL;
 326
 327         gensec_ntlmssp_state->neg_flags =
 328                 NTLMSSP_NEGOTIATE_NTLM |
 329                 NTLMSSP_REQUEST_TARGET;
 330
 331         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "128bit", true)) {
 332                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 333         }
 334
 335         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "56bit", false)) {
 336                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 337         }
 338
 339         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "lm_key", false)) {
 340                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_LM_KEY;
 341         }
 342
 343         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "keyexchange", true)) {
 344                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 345         }
 346
 347         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "alwayssign", true)) {
 348                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 349         }
 350
 351         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "ntlmssp_client", "ntlm2", true)) {
 352                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 353         } else {
 354                 /* apparently we can't do ntlmv2 if we don't do ntlm2 */
 355                 gensec_ntlmssp_state->use_ntlmv2 = false;
 356         }
 357
 358         if (gensec_security->want_features & GENSEC_FEATURE_SESSION_KEY) {
 359                 /*
 360                  * We need to set this to allow a later SetPassword
 361                  * via the SAMR pipe to succeed. Strange.... We could
 362                  * also add  NTLMSSP_NEGOTIATE_SEAL here. JRA.
 363                  *
 364                  * Without this, Windows will not create the master key
 365                  * that it thinks is only used for NTLMSSP signing and
 366                  * sealing.  (It is actually pulled out and used directly)
 367                  */
 368                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 369         }
 370         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 371                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 372         }
 373         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 374                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 375         }
 376
 377         gensec_security->private_data = gensec_ntlmssp_state;
 378
 379         return NT_STATUS_OK;
 380 }
 381