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