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
  32 /*********************************************************************
  33  Client side NTLMSSP
  34 *********************************************************************/
  35
  36 /**
  37  * Next state function for the Initial packet
  38  *
  39  * @param ntlmssp_state NTLMSSP State
  40  * @param out_mem_ctx The DATA_BLOB *out will be allocated on this context
  41  * @param in A NULL data blob (input ignored)
  42  * @param out The initial negotiate request to the server, as an talloc()ed DATA_BLOB, on out_mem_ctx
  43  * @return Errors or NT_STATUS_OK.
  44  */
  45
  46 NTSTATUS ntlmssp_client_initial(struct gensec_security *gensec_security,
  47                                 TALLOC_CTX *out_mem_ctx,
  48                                 DATA_BLOB in, DATA_BLOB *out)
  49 {
  50         struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
  51         const char *domain = gensec_ntlmssp_state->domain;
  52         const char *workstation = cli_credentials_get_workstation(gensec_security->credentials);
  53
  54         /* These don't really matter in the initial packet, so don't panic if they are not set */
  55         if (!domain) {
  56                 domain = "";
  57         }
  58
  59         if (!workstation) {
  60                 workstation = "";
  61         }
  62
  63         if (gensec_ntlmssp_state->unicode) {
  64                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_UNICODE;
  65         } else {
  66                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_OEM;
  67         }
  68
  69         if (gensec_ntlmssp_state->use_ntlmv2) {
  70                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
  71         }
  72
  73         /* generate the ntlmssp negotiate packet */
  74         msrpc_gen(out_mem_ctx,
  75                   out, "CddAA",
  76                   "NTLMSSP",
  77                   NTLMSSP_NEGOTIATE,
  78                   gensec_ntlmssp_state->neg_flags,
  79                   domain,
  80                   workstation);
  81
  82         gensec_ntlmssp_state->expected_state = NTLMSSP_CHALLENGE;
  83
  84         return NT_STATUS_MORE_PROCESSING_REQUIRED;
  85 }
  86
  87 /**
  88  * Next state function for the Challenge Packet.  Generate an auth packet.
  89  *
  90  * @param gensec_security GENSEC state
  91  * @param out_mem_ctx Memory context for *out
  92  * @param in The server challnege, as a DATA_BLOB.  reply.data must be NULL
  93  * @param out The next request (auth packet) to the server, as an allocated DATA_BLOB, on the out_mem_ctx context
  94  * @return Errors or NT_STATUS_OK.
  95  */
  96
  97 NTSTATUS ntlmssp_client_challenge(struct gensec_security *gensec_security,
  98                                   TALLOC_CTX *out_mem_ctx,
  99                                   const DATA_BLOB in, DATA_BLOB *out)
 100 {
 101         struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
 102         uint32_t chal_flags, ntlmssp_command, unkn1, unkn2;
 103         DATA_BLOB server_domain_blob;
 104         DATA_BLOB challenge_blob;
 105         DATA_BLOB target_info = data_blob(NULL, 0);
 106         char *server_domain;
 107         const char *chal_parse_string;
 108         const char *auth_gen_string;
 109         DATA_BLOB lm_response = data_blob(NULL, 0);
 110         DATA_BLOB nt_response = data_blob(NULL, 0);
 111         DATA_BLOB session_key = data_blob(NULL, 0);
 112         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 113         DATA_BLOB encrypted_session_key = data_blob(NULL, 0);
 114         NTSTATUS nt_status;
 115         int flags = 0;
 116         const char *user, *domain;
 117
 118         TALLOC_CTX *mem_ctx = talloc_new(out_mem_ctx);
 119         if (!mem_ctx) {
 120                 return NT_STATUS_NO_MEMORY;
 121         }
 122
 123         if (!msrpc_parse(mem_ctx,
 124                          &in, "CdBd",
 125                          "NTLMSSP",
 126                          &ntlmssp_command,
 127                          &server_domain_blob,
 128                          &chal_flags)) {
 129                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#1)\n"));
 130                 dump_data(2, in.data, in.length);
 131                 talloc_free(mem_ctx);
 132
 133                 return NT_STATUS_INVALID_PARAMETER;
 134         }
 135
 136         data_blob_free(&server_domain_blob);
 137
 138         DEBUG(3, ("Got challenge flags:\n"));
 139         debug_ntlmssp_flags(chal_flags);
 140
 141         ntlmssp_handle_neg_flags(gensec_ntlmssp_state, chal_flags, gensec_ntlmssp_state->allow_lm_key);
 142
 143         if (gensec_ntlmssp_state->unicode) {
 144                 if (chal_flags & NTLMSSP_NEGOTIATE_TARGET_INFO) {
 145                         chal_parse_string = "CdUdbddB";
 146                 } else {
 147                         chal_parse_string = "CdUdbdd";
 148                 }
 149                 auth_gen_string = "CdBBUUUBd";
 150         } else {
 151                 if (chal_flags & NTLMSSP_NEGOTIATE_TARGET_INFO) {
 152                         chal_parse_string = "CdAdbddB";
 153                 } else {
 154                         chal_parse_string = "CdAdbdd";
 155                 }
 156
 157                 auth_gen_string = "CdBBAAABd";
 158         }
 159
 160         if (!msrpc_parse(mem_ctx,
 161                          &in, chal_parse_string,
 162                          "NTLMSSP",
 163                          &ntlmssp_command,
 164                          &server_domain,
 165                          &chal_flags,
 166                          &challenge_blob, 8,
 167                          &unkn1, &unkn2,
 168                          &target_info)) {
 169                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#2)\n"));
 170                 dump_data(2, in.data, in.length);
 171                 talloc_free(mem_ctx);
 172                 return NT_STATUS_INVALID_PARAMETER;
 173         }
 174
 175         gensec_ntlmssp_state->server_domain = server_domain;
 176
 177         if (challenge_blob.length != 8) {
 178                 talloc_free(mem_ctx);
 179                 return NT_STATUS_INVALID_PARAMETER;
 180         }
 181
 182         cli_credentials_get_ntlm_username_domain(gensec_security->credentials, mem_ctx,
 183                                                  &user, &domain);
 184
 185         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 186                 flags |= CLI_CRED_NTLM2;
 187         }
 188         if (gensec_ntlmssp_state->use_ntlmv2) {
 189                 flags |= CLI_CRED_NTLMv2_AUTH;
 190         }
 191         if (gensec_ntlmssp_state->use_nt_response) {
 192                 flags |= CLI_CRED_NTLM_AUTH;
 193         }
 194         if (lp_client_lanman_auth(gensec_security->settings->lp_ctx)) {
 195                 flags |= CLI_CRED_LANMAN_AUTH;
 196         }
 197
 198         nt_status = cli_credentials_get_ntlm_response(gensec_security->credentials, mem_ctx,
 199                                                       &flags, challenge_blob, target_info,
 200                                                       &lm_response, &nt_response,
 201                                                       &lm_session_key, &session_key);
 202
 203         if (!NT_STATUS_IS_OK(nt_status)) {
 204                 return nt_status;
 205         }
 206
 207         if (!(flags & CLI_CRED_LANMAN_AUTH)) {
 208                 /* LM Key is still possible, just silly.  Fortunetly
 209                  * we require command line options to end up here */
 210                 /* gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY; */
 211         }
 212
 213         if (!(flags & CLI_CRED_NTLM2)) {
 214                 /* NTLM2 is incompatible... */
 215                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 216         }
 217
 218         if ((gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 219             && lp_client_lanman_auth(gensec_security->settings->lp_ctx) && lm_session_key.length == 16) {
 220                 DATA_BLOB new_session_key = data_blob_talloc(mem_ctx, NULL, 16);
 221                 if (lm_response.length == 24) {
 222                         SMBsesskeygen_lm_sess_key(lm_session_key.data, lm_response.data,
 223                                                   new_session_key.data);
 224                 } else {
 225                         static const uint8_t zeros[24];
 226                         SMBsesskeygen_lm_sess_key(lm_session_key.data, zeros,
 227                                                   new_session_key.data);
 228                 }
 229                 session_key = new_session_key;
 230                 dump_data_pw("LM session key\n", session_key.data, session_key.length);
 231         }
 232
 233
 234         /* Key exchange encryptes a new client-generated session key with
 235            the password-derived key */
 236         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 237                 /* Make up a new session key */
 238                 uint8_t client_session_key[16];
 239                 generate_secret_buffer(client_session_key, sizeof(client_session_key));
 240
 241                 /* Encrypt the new session key with the old one */
 242                 encrypted_session_key = data_blob_talloc(gensec_ntlmssp_state,
 243                                                          client_session_key, sizeof(client_session_key));
 244                 dump_data_pw("KEY_EXCH session key:\n", encrypted_session_key.data, encrypted_session_key.length);
 245                 arcfour_crypt(encrypted_session_key.data, session_key.data, encrypted_session_key.length);
 246                 dump_data_pw("KEY_EXCH session key (enc):\n", encrypted_session_key.data, encrypted_session_key.length);
 247
 248                 /* Mark the new session key as the 'real' session key */
 249                 session_key = data_blob_talloc(mem_ctx, client_session_key, sizeof(client_session_key));
 250         }
 251
 252         DEBUG(3, ("NTLMSSP: Set final flags:\n"));
 253         debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
 254
 255         /* this generates the actual auth packet */
 256         if (!msrpc_gen(mem_ctx,
 257                        out, auth_gen_string,
 258                        "NTLMSSP",
 259                        NTLMSSP_AUTH,
 260                        lm_response.data, lm_response.length,
 261                        nt_response.data, nt_response.length,
 262                        domain,
 263                        user,
 264                        cli_credentials_get_workstation(gensec_security->credentials),
 265                        encrypted_session_key.data, encrypted_session_key.length,
 266                        gensec_ntlmssp_state->neg_flags)) {
 267                 talloc_free(mem_ctx);
 268                 return NT_STATUS_NO_MEMORY;
 269         }
 270
 271         gensec_ntlmssp_state->session_key = session_key;
 272         talloc_steal(gensec_ntlmssp_state, session_key.data);
 273
 274         talloc_steal(out_mem_ctx, out->data);
 275
 276         gensec_ntlmssp_state->chal = challenge_blob;
 277         gensec_ntlmssp_state->lm_resp = lm_response;
 278         talloc_steal(gensec_ntlmssp_state->lm_resp.data, lm_response.data);
 279         gensec_ntlmssp_state->nt_resp = nt_response;
 280         talloc_steal(gensec_ntlmssp_state->nt_resp.data, nt_response.data);
 281
 282         gensec_ntlmssp_state->expected_state = NTLMSSP_DONE;
 283
 284         if (gensec_security->want_features & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL)) {
 285                 nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
 286                 if (!NT_STATUS_IS_OK(nt_status)) {
 287                         DEBUG(1, ("Could not setup NTLMSSP signing/sealing system (error was: %s)\n",
 288                                   nt_errstr(nt_status)));
 289                         talloc_free(mem_ctx);
 290                         return nt_status;
 291                 }
 292         }
 293
 294         talloc_free(mem_ctx);
 295         return NT_STATUS_OK;
 296 }
 297
 298 NTSTATUS gensec_ntlmssp_client_start(struct gensec_security *gensec_security)
 299 {
 300         struct gensec_ntlmssp_state *gensec_ntlmssp_state;
 301         NTSTATUS nt_status;
 302
 303         nt_status = gensec_ntlmssp_start(gensec_security);
 304         NT_STATUS_NOT_OK_RETURN(nt_status);
 305
 306         gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
 307
 308         gensec_ntlmssp_state->role = NTLMSSP_CLIENT;
 309
 310         gensec_ntlmssp_state->domain = lp_workgroup(gensec_security->settings->lp_ctx);
 311
 312         gensec_ntlmssp_state->unicode = gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "unicode", true);
 313
 314         gensec_ntlmssp_state->use_nt_response = gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "send_nt_reponse", true);
 315
 316         gensec_ntlmssp_state->allow_lm_key = (lp_client_lanman_auth(gensec_security->settings->lp_ctx)
 317                                               && (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "allow_lm_key", false)
 318                                                   || gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "lm_key", false)));
 319
 320         gensec_ntlmssp_state->use_ntlmv2 = lp_client_ntlmv2_auth(gensec_security->settings->lp_ctx);
 321
 322         gensec_ntlmssp_state->expected_state = NTLMSSP_INITIAL;
 323
 324         gensec_ntlmssp_state->neg_flags =
 325                 NTLMSSP_NEGOTIATE_NTLM |
 326                 NTLMSSP_REQUEST_TARGET;
 327
 328         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "128bit", true)) {
 329                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 330         }
 331
 332         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "56bit", false)) {
 333                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 334         }
 335
 336         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "lm_key", false)) {
 337                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_LM_KEY;
 338         }
 339
 340         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "keyexchange", true)) {
 341                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 342         }
 343
 344         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "alwayssign", true)) {
 345                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 346         }
 347
 348         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_client", "ntlm2", true)) {
 349                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 350         } else {
 351                 /* apparently we can't do ntlmv2 if we don't do ntlm2 */
 352                 gensec_ntlmssp_state->use_ntlmv2 = false;
 353         }
 354
 355         if (gensec_security->want_features & GENSEC_FEATURE_SESSION_KEY) {
 356                 /*
 357                  * We need to set this to allow a later SetPassword
 358                  * via the SAMR pipe to succeed. Strange.... We could
 359                  * also add  NTLMSSP_NEGOTIATE_SEAL here. JRA.
 360                  *
 361                  * Without this, Windows will not create the master key
 362                  * that it thinks is only used for NTLMSSP signing and
 363                  * sealing.  (It is actually pulled out and used directly)
 364                  */
 365                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 366         }
 367         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 368                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 369         }
 370         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 371                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 372         }
 373
 374         gensec_security->private_data = gensec_ntlmssp_state;
 375
 376         return NT_STATUS_OK;
 377 }
 378