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 2 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, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #include "includes.h"
  26 #include "auth/auth.h"
  27 #include "auth/ntlmssp/ntlmssp.h"
  28 #include "lib/crypto/crypto.h"
  29 #include "libcli/auth/proto.h"
  30
  31 /*********************************************************************
  32  Client side NTLMSSP
  33 *********************************************************************/
  34
  35 /**
  36  * Next state function for the Initial packet
  37  *
  38  * @param ntlmssp_state NTLMSSP State
  39  * @param out_mem_ctx The DATA_BLOB *out will be allocated on this context
  40  * @param in A NULL data blob (input ignored)
  41  * @param out The initial negotiate request to the server, as an talloc()ed DATA_BLOB, on out_mem_ctx
  42  * @return Errors or NT_STATUS_OK.
  43  */
  44
  45 NTSTATUS ntlmssp_client_initial(struct gensec_security *gensec_security,
  46                                 TALLOC_CTX *out_mem_ctx,
  47                                 DATA_BLOB in, DATA_BLOB *out)
  48 {
  49         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
  50
  51         if (gensec_ntlmssp_state->unicode) {
  52                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_UNICODE;
  53         } else {
  54                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_OEM;
  55         }
  56
  57         if (gensec_ntlmssp_state->use_ntlmv2) {
  58                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
  59         }
  60
  61         /* generate the ntlmssp negotiate packet */
  62         msrpc_gen(out_mem_ctx,
  63                   out, "CddAA",
  64                   "NTLMSSP",
  65                   NTLMSSP_NEGOTIATE,
  66                   gensec_ntlmssp_state->neg_flags,
  67                   gensec_ntlmssp_state->get_domain(),
  68                   cli_credentials_get_workstation(gensec_security->credentials));
  69
  70         gensec_ntlmssp_state->expected_state = NTLMSSP_CHALLENGE;
  71
  72         return NT_STATUS_MORE_PROCESSING_REQUIRED;
  73 }
  74
  75 /**
  76  * Next state function for the Challenge Packet.  Generate an auth packet.
  77  *
  78  * @param gensec_security GENSEC state
  79  * @param out_mem_ctx Memory context for *out
  80  * @param in The server challnege, as a DATA_BLOB.  reply.data must be NULL
  81  * @param out The next request (auth packet) to the server, as an allocated DATA_BLOB, on the out_mem_ctx context
  82  * @return Errors or NT_STATUS_OK.
  83  */
  84
  85 NTSTATUS ntlmssp_client_challenge(struct gensec_security *gensec_security,
  86                                   TALLOC_CTX *out_mem_ctx,
  87                                   const DATA_BLOB in, DATA_BLOB *out)
  88 {
  89         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
  90         uint32_t chal_flags, ntlmssp_command, unkn1, unkn2;
  91         DATA_BLOB server_domain_blob;
  92         DATA_BLOB challenge_blob;
  93         DATA_BLOB target_info = data_blob(NULL, 0);
  94         char *server_domain;
  95         const char *chal_parse_string;
  96         const char *auth_gen_string;
  97         DATA_BLOB lm_response = data_blob(NULL, 0);
  98         DATA_BLOB nt_response = data_blob(NULL, 0);
  99         DATA_BLOB session_key = data_blob(NULL, 0);
 100         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 101         DATA_BLOB encrypted_session_key = data_blob(NULL, 0);
 102         NTSTATUS nt_status;
 103         int flags = 0;
 104         const char *user, *domain;
 105
 106         TALLOC_CTX *mem_ctx = talloc_new(out_mem_ctx);
 107         if (!mem_ctx) {
 108                 return NT_STATUS_NO_MEMORY;
 109         }
 110
 111         if (!msrpc_parse(mem_ctx,
 112                          &in, "CdBd",
 113                          "NTLMSSP",
 114                          &ntlmssp_command,
 115                          &server_domain_blob,
 116                          &chal_flags)) {
 117                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#1)\n"));
 118                 dump_data(2, in.data, in.length);
 119                 talloc_free(mem_ctx);
 120
 121                 return NT_STATUS_INVALID_PARAMETER;
 122         }
 123
 124         data_blob_free(&server_domain_blob);
 125
 126         DEBUG(3, ("Got challenge flags:\n"));
 127         debug_ntlmssp_flags(chal_flags);
 128
 129         ntlmssp_handle_neg_flags(gensec_ntlmssp_state, chal_flags, gensec_ntlmssp_state->allow_lm_key);
 130
 131         if (gensec_ntlmssp_state->unicode) {
 132                 if (chal_flags & NTLMSSP_CHAL_TARGET_INFO) {
 133                         chal_parse_string = "CdUdbddB";
 134                 } else {
 135                         chal_parse_string = "CdUdbdd";
 136                 }
 137                 auth_gen_string = "CdBBUUUBd";
 138         } else {
 139                 if (chal_flags & NTLMSSP_CHAL_TARGET_INFO) {
 140                         chal_parse_string = "CdAdbddB";
 141                 } else {
 142                         chal_parse_string = "CdAdbdd";
 143                 }
 144
 145                 auth_gen_string = "CdBBAAABd";
 146         }
 147
 148         if (!msrpc_parse(mem_ctx,
 149                          &in, chal_parse_string,
 150                          "NTLMSSP",
 151                          &ntlmssp_command,
 152                          &server_domain,
 153                          &chal_flags,
 154                          &challenge_blob, 8,
 155                          &unkn1, &unkn2,
 156                          &target_info)) {
 157                 DEBUG(1, ("Failed to parse the NTLMSSP Challenge: (#2)\n"));
 158                 dump_data(2, in.data, in.length);
 159                 talloc_free(mem_ctx);
 160                 return NT_STATUS_INVALID_PARAMETER;
 161         }
 162
 163         gensec_ntlmssp_state->server_domain = server_domain;
 164
 165         if (challenge_blob.length != 8) {
 166                 talloc_free(mem_ctx);
 167                 return NT_STATUS_INVALID_PARAMETER;
 168         }
 169
 170         cli_credentials_get_ntlm_username_domain(gensec_security->credentials, mem_ctx,
 171                                                  &user, &domain);
 172
 173         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 174                 flags |= CLI_CRED_NTLM2;
 175         }
 176         if (gensec_ntlmssp_state->use_ntlmv2) {
 177                 flags |= CLI_CRED_NTLMv2_AUTH;
 178         }
 179         if (gensec_ntlmssp_state->use_nt_response) {
 180                 flags |= CLI_CRED_NTLM_AUTH;
 181         }
 182         if (lp_client_lanman_auth()) {
 183                 flags |= CLI_CRED_LANMAN_AUTH;
 184         }
 185
 186         nt_status = cli_credentials_get_ntlm_response(gensec_security->credentials, mem_ctx,
 187                                                       &flags, challenge_blob, target_info,
 188                                                       &lm_response, &nt_response,
 189                                                       &lm_session_key, &session_key);
 190
 191         if (!NT_STATUS_IS_OK(nt_status)) {
 192                 return nt_status;
 193         }
 194
 195         if (!(flags & CLI_CRED_LANMAN_AUTH)) {
 196                 /* LM Key is incompatible... */
 197                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 198         }
 199
 200         if (!(flags & CLI_CRED_NTLM2)) {
 201                 /* NTLM2 is incompatible... */
 202                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 203         }
 204
 205         if ((gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 206             && lp_client_lanman_auth() && lm_session_key.length == 16) {
 207                 DATA_BLOB new_session_key = data_blob_talloc(mem_ctx, NULL, 16);
 208                 if (lm_response.length == 24) {
 209                         SMBsesskeygen_lm_sess_key(lm_session_key.data, lm_response.data,
 210                                                   new_session_key.data);
 211                 } else {
 212                         static const uint8_t zeros[24];
 213                         SMBsesskeygen_lm_sess_key(lm_session_key.data, zeros,
 214                                                   new_session_key.data);
 215                 }
 216                 session_key = new_session_key;
 217                 dump_data_pw("LM session key\n", session_key.data, session_key.length);
 218         }
 219
 220
 221         /* Key exchange encryptes a new client-generated session key with
 222            the password-derived key */
 223         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 224                 /* Make up a new session key */
 225                 uint8_t client_session_key[16];
 226                 generate_random_buffer(client_session_key, sizeof(client_session_key));
 227
 228                 /* Encrypt the new session key with the old one */
 229                 encrypted_session_key = data_blob_talloc(gensec_ntlmssp_state,
 230                                                          client_session_key, sizeof(client_session_key));
 231                 dump_data_pw("KEY_EXCH session key:\n", encrypted_session_key.data, encrypted_session_key.length);
 232                 arcfour_crypt(encrypted_session_key.data, session_key.data, encrypted_session_key.length);
 233                 dump_data_pw("KEY_EXCH session key (enc):\n", encrypted_session_key.data, encrypted_session_key.length);
 234
 235                 /* Mark the new session key as the 'real' session key */
 236                 session_key = data_blob_talloc(mem_ctx, client_session_key, sizeof(client_session_key));
 237         }
 238
 239         DEBUG(3, ("NTLMSSP: Set final flags:\n"));
 240         debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
 241
 242         /* this generates the actual auth packet */
 243         if (!msrpc_gen(mem_ctx,
 244                        out, auth_gen_string,
 245                        "NTLMSSP",
 246                        NTLMSSP_AUTH,
 247                        lm_response.data, lm_response.length,
 248                        nt_response.data, nt_response.length,
 249                        domain,
 250                        user,
 251                        cli_credentials_get_workstation(gensec_security->credentials),
 252                        encrypted_session_key.data, encrypted_session_key.length,
 253                        gensec_ntlmssp_state->neg_flags)) {
 254                 talloc_free(mem_ctx);
 255                 return NT_STATUS_NO_MEMORY;
 256         }
 257
 258         gensec_ntlmssp_state->session_key = session_key;
 259         talloc_steal(gensec_ntlmssp_state, session_key.data);
 260
 261         talloc_steal(out_mem_ctx, out->data);
 262
 263         gensec_ntlmssp_state->chal = challenge_blob;
 264         gensec_ntlmssp_state->lm_resp = lm_response;
 265         talloc_steal(gensec_ntlmssp_state->lm_resp.data, lm_response.data);
 266         gensec_ntlmssp_state->nt_resp = nt_response;
 267         talloc_steal(gensec_ntlmssp_state->nt_resp.data, nt_response.data);
 268
 269         gensec_ntlmssp_state->expected_state = NTLMSSP_DONE;
 270
 271         if (gensec_security->want_features & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL)) {
 272                 nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
 273                 if (!NT_STATUS_IS_OK(nt_status)) {
 274                         DEBUG(1, ("Could not setup NTLMSSP signing/sealing system (error was: %s)\n",
 275                                   nt_errstr(nt_status)));
 276                         talloc_free(mem_ctx);
 277                         return nt_status;
 278                 }
 279         }
 280
 281         talloc_free(mem_ctx);
 282         return NT_STATUS_OK;
 283 }
 284
 285 NTSTATUS gensec_ntlmssp_client_start(struct gensec_security *gensec_security)
 286 {
 287         struct gensec_ntlmssp_state *gensec_ntlmssp_state;
 288         NTSTATUS nt_status;
 289
 290         nt_status = gensec_ntlmssp_start(gensec_security);
 291         NT_STATUS_NOT_OK_RETURN(nt_status);
 292
 293         gensec_ntlmssp_state = gensec_security->private_data;
 294
 295         gensec_ntlmssp_state->role = NTLMSSP_CLIENT;
 296
 297         gensec_ntlmssp_state->get_domain = lp_workgroup;
 298
 299         gensec_ntlmssp_state->unicode = lp_parm_bool(-1, "ntlmssp_client", "unicode", True);
 300
 301         gensec_ntlmssp_state->use_nt_response = lp_parm_bool(-1, "ntlmssp_client", "send_nt_reponse", True);
 302
 303         gensec_ntlmssp_state->allow_lm_key = (lp_client_lanman_auth()
 304                                               && (lp_parm_bool(-1, "ntlmssp_client", "allow_lm_key", False)
 305                                                   || lp_parm_bool(-1, "ntlmssp_client", "lm_key", False)));
 306
 307         gensec_ntlmssp_state->use_ntlmv2 = lp_client_ntlmv2_auth();
 308
 309         gensec_ntlmssp_state->expected_state = NTLMSSP_INITIAL;
 310
 311         gensec_ntlmssp_state->neg_flags =
 312                 NTLMSSP_NEGOTIATE_NTLM |
 313                 NTLMSSP_REQUEST_TARGET;
 314
 315         if (lp_parm_bool(-1, "ntlmssp_client", "128bit", True)) {
 316                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 317         }
 318
 319         if (lp_parm_bool(-1, "ntlmssp_client", "56bit", False)) {
 320                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 321         }
 322
 323         if (lp_parm_bool(-1, "ntlmssp_client", "lm_key", False)) {
 324                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_LM_KEY;
 325         }
 326
 327         if (lp_parm_bool(-1, "ntlmssp_client", "keyexchange", True)) {
 328                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 329         }
 330
 331         if (lp_parm_bool(-1, "ntlmssp_client", "ntlm2", True)) {
 332                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 333         } else {
 334                 /* apparently we can't do ntlmv2 if we don't do ntlm2 */
 335                 gensec_ntlmssp_state->use_ntlmv2 = False;
 336         }
 337
 338         if (gensec_security->want_features & GENSEC_FEATURE_SESSION_KEY) {
 339                 /*
 340                  * We need to set this to allow a later SetPassword
 341                  * via the SAMR pipe to succeed. Strange.... We could
 342                  * also add  NTLMSSP_NEGOTIATE_SEAL here. JRA.
 343                  *
 344                  * Without this, Windows will not create the master key
 345                  * that it thinks is only used for NTLMSSP signing and
 346                  * sealing.  (It is actually pulled out and used directly)
 347                  */
 348                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 349         }
 350         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 351                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 352         }
 353         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 354                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 355         }
 356
 357         gensec_security->private_data = gensec_ntlmssp_state;
 358
 359         return NT_STATUS_OK;
 360 }
 361