auth/ntlmssp/gensec_ntlmssp_server.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 "system/network.h"
  26 #include "lib/tsocket/tsocket.h"
  27 #include "auth/ntlmssp/ntlmssp.h"
  28 #include "../librpc/gen_ndr/ndr_ntlmssp.h"
  29 #include "auth/ntlmssp/ntlmssp_ndr.h"
  30 #include "auth/ntlmssp/ntlmssp_private.h"
  31 #include "../libcli/auth/libcli_auth.h"
  32 #include "../lib/crypto/crypto.h"
  33 #include "auth/gensec/gensec.h"
  34 #include "auth/common_auth.h"
  35 #include "param/param.h"
  36
  37 /**
  38  * Next state function for the Negotiate packet (GENSEC wrapper)
  39  *
  40  * @param gensec_security GENSEC state
  41  * @param out_mem_ctx Memory context for *out
  42  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
  43  * @param out The reply, as an allocated DATA_BLOB, caller to free.
  44  * @return Errors or MORE_PROCESSING_REQUIRED if (normal) a reply is required.
  45  */
  46
  47 NTSTATUS gensec_ntlmssp_server_negotiate(struct gensec_security *gensec_security,
  48                                          TALLOC_CTX *out_mem_ctx,
  49                                          const DATA_BLOB request, DATA_BLOB *reply)
  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         return ntlmssp_server_negotiate(ntlmssp_state, out_mem_ctx, request, reply);
  56 }
  57
  58 /**
  59  * Next state function for the Authenticate packet (GENSEC wrapper)
  60  *
  61  * @param gensec_security GENSEC state
  62  * @param out_mem_ctx Memory context for *out
  63  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
  64  * @param out The reply, as an allocated DATA_BLOB, caller to free.
  65  * @return Errors or NT_STATUS_OK if authentication sucessful
  66  */
  67
  68 NTSTATUS gensec_ntlmssp_server_auth(struct gensec_security *gensec_security,
  69                                     TALLOC_CTX *out_mem_ctx,
  70                                     const DATA_BLOB in, DATA_BLOB *out)
  71 {
  72         struct gensec_ntlmssp_context *gensec_ntlmssp =
  73                 talloc_get_type_abort(gensec_security->private_data,
  74                                       struct gensec_ntlmssp_context);
  75         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
  76         return ntlmssp_server_auth(ntlmssp_state, out_mem_ctx, in, out);
  77 }
  78
  79 /**
  80  * Return the challenge as determined by the authentication subsystem
  81  * @return an 8 byte random challenge
  82  */
  83
  84 static NTSTATUS auth_ntlmssp_get_challenge(const struct ntlmssp_state *ntlmssp_state,
  85                                            uint8_t chal[8])
  86 {
  87         struct gensec_ntlmssp_context *gensec_ntlmssp =
  88                 talloc_get_type_abort(ntlmssp_state->callback_private,
  89                                       struct gensec_ntlmssp_context);
  90         struct auth4_context *auth_context = gensec_ntlmssp->gensec_security->auth_context;
  91         NTSTATUS status = NT_STATUS_NOT_IMPLEMENTED;
  92
  93         if (auth_context->get_challenge) {
  94                 status = auth_context->get_challenge(auth_context, chal);
  95                 if (!NT_STATUS_IS_OK(status)) {
  96                         DEBUG(1, ("auth_ntlmssp_get_challenge: failed to get challenge: %s\n",
  97                                   nt_errstr(status)));
  98                         return status;
  99                 }
 100         }
 101
 102         return status;
 103 }
 104
 105 /**
 106  * Some authentication methods 'fix' the challenge, so we may not be able to set it
 107  *
 108  * @return If the effective challenge used by the auth subsystem may be modified
 109  */
 110 static bool auth_ntlmssp_may_set_challenge(const struct ntlmssp_state *ntlmssp_state)
 111 {
 112         struct gensec_ntlmssp_context *gensec_ntlmssp =
 113                 talloc_get_type_abort(ntlmssp_state->callback_private,
 114                                       struct gensec_ntlmssp_context);
 115         struct auth4_context *auth_context = gensec_ntlmssp->gensec_security->auth_context;
 116
 117         if (auth_context->challenge_may_be_modified) {
 118                 return auth_context->challenge_may_be_modified(auth_context);
 119         }
 120         return false;
 121 }
 122
 123 /**
 124  * NTLM2 authentication modifies the effective challenge,
 125  * @param challenge The new challenge value
 126  */
 127 static NTSTATUS auth_ntlmssp_set_challenge(struct ntlmssp_state *ntlmssp_state, DATA_BLOB *challenge)
 128 {
 129         struct gensec_ntlmssp_context *gensec_ntlmssp =
 130                 talloc_get_type_abort(ntlmssp_state->callback_private,
 131                                       struct gensec_ntlmssp_context);
 132         struct auth4_context *auth_context = gensec_ntlmssp->gensec_security->auth_context;
 133         NTSTATUS nt_status = NT_STATUS_NOT_IMPLEMENTED;
 134         const uint8_t *chal;
 135
 136         if (challenge->length != 8) {
 137                 return NT_STATUS_INVALID_PARAMETER;
 138         }
 139
 140         chal = challenge->data;
 141
 142         if (auth_context->set_challenge) {
 143                 nt_status = auth_context->set_challenge(auth_context,
 144                                                         chal,
 145                                                         "NTLMSSP callback (NTLM2)");
 146         }
 147         return nt_status;
 148 }
 149
 150 /**
 151  * Check the password on an NTLMSSP login.
 152  *
 153  * Return the session keys used on the connection.
 154  */
 155
 156 static NTSTATUS auth_ntlmssp_check_password(struct ntlmssp_state *ntlmssp_state,
 157                                             TALLOC_CTX *mem_ctx,
 158                                             DATA_BLOB *user_session_key, DATA_BLOB *lm_session_key)
 159 {
 160         struct gensec_ntlmssp_context *gensec_ntlmssp =
 161                 talloc_get_type_abort(ntlmssp_state->callback_private,
 162                                       struct gensec_ntlmssp_context);
 163         struct auth4_context *auth_context = gensec_ntlmssp->gensec_security->auth_context;
 164         NTSTATUS nt_status = NT_STATUS_NOT_IMPLEMENTED;
 165         struct auth_usersupplied_info *user_info;
 166
 167         user_info = talloc_zero(ntlmssp_state, struct auth_usersupplied_info);
 168         if (!user_info) {
 169                 return NT_STATUS_NO_MEMORY;
 170         }
 171
 172         user_info->logon_parameters = MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT;
 173         user_info->flags = 0;
 174         user_info->mapped_state = false;
 175         user_info->client.account_name = ntlmssp_state->user;
 176         user_info->client.domain_name = ntlmssp_state->domain;
 177         user_info->workstation_name = ntlmssp_state->client.netbios_name;
 178         user_info->remote_host = gensec_get_remote_address(gensec_ntlmssp->gensec_security);
 179
 180         user_info->password_state = AUTH_PASSWORD_RESPONSE;
 181         user_info->password.response.lanman = ntlmssp_state->lm_resp;
 182         user_info->password.response.lanman.data = talloc_steal(user_info, ntlmssp_state->lm_resp.data);
 183         user_info->password.response.nt = ntlmssp_state->nt_resp;
 184         user_info->password.response.nt.data = talloc_steal(user_info, ntlmssp_state->nt_resp.data);
 185
 186         if (auth_context->check_password) {
 187                 nt_status = auth_context->check_password(auth_context,
 188                                                          gensec_ntlmssp,
 189                                                          user_info,
 190                                                          &gensec_ntlmssp->server_returned_info,
 191                                                          user_session_key, lm_session_key);
 192         }
 193         talloc_free(user_info);
 194
 195         if (!NT_STATUS_IS_OK(nt_status)) {
 196                 DEBUG(5,("%s: Checking NTLMSSP password for %s\\%s failed: %s\n",
 197                          __location__,
 198                          user_info->client.domain_name,
 199                          user_info->client.account_name,
 200                          nt_errstr(nt_status)));
 201         }
 202
 203         NT_STATUS_NOT_OK_RETURN(nt_status);
 204
 205         talloc_steal(mem_ctx, user_session_key->data);
 206         talloc_steal(mem_ctx, lm_session_key->data);
 207
 208         return nt_status;
 209 }
 210
 211 /**
 212  * Return the credentials of a logged on user, including session keys
 213  * etc.
 214  *
 215  * Only valid after a successful authentication
 216  *
 217  * May only be called once per authentication.
 218  *
 219  */
 220
 221 NTSTATUS gensec_ntlmssp_session_info(struct gensec_security *gensec_security,
 222                                      TALLOC_CTX *mem_ctx,
 223                                      struct auth_session_info **session_info)
 224 {
 225         NTSTATUS nt_status;
 226         struct gensec_ntlmssp_context *gensec_ntlmssp =
 227                 talloc_get_type_abort(gensec_security->private_data,
 228                                       struct gensec_ntlmssp_context);
 229         uint32_t session_info_flags = 0;
 230
 231         if (gensec_security->want_features & GENSEC_FEATURE_UNIX_TOKEN) {
 232                 session_info_flags |= AUTH_SESSION_INFO_UNIX_TOKEN;
 233         }
 234
 235         session_info_flags |= AUTH_SESSION_INFO_DEFAULT_GROUPS;
 236
 237         if (gensec_security->auth_context && gensec_security->auth_context->generate_session_info) {
 238                 nt_status = gensec_security->auth_context->generate_session_info(mem_ctx, gensec_security->auth_context,
 239                                                                                  gensec_ntlmssp->server_returned_info,
 240                                                                                  gensec_ntlmssp->ntlmssp_state->user,
 241                                                                                  session_info_flags,
 242                                                                                  session_info);
 243         } else {
 244                 DEBUG(0, ("Cannot generate a session_info without the auth_context\n"));
 245                 return NT_STATUS_INTERNAL_ERROR;
 246         }
 247
 248         NT_STATUS_NOT_OK_RETURN(nt_status);
 249
 250         nt_status = gensec_ntlmssp_session_key(gensec_security, *session_info,
 251                                                &(*session_info)->session_key);
 252         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_USER_SESSION_KEY)) {
 253                 (*session_info)->session_key = data_blob_null;
 254                 nt_status = NT_STATUS_OK;
 255         }
 256
 257         return nt_status;
 258 }
 259
 260 /**
 261  * Start NTLMSSP on the server side
 262  *
 263  */
 264 NTSTATUS gensec_ntlmssp_server_start(struct gensec_security *gensec_security)
 265 {
 266         NTSTATUS nt_status;
 267         struct ntlmssp_state *ntlmssp_state;
 268         struct gensec_ntlmssp_context *gensec_ntlmssp;
 269         const char *netbios_name;
 270         const char *netbios_domain;
 271         const char *dns_name;
 272         const char *dns_domain;
 273
 274         nt_status = gensec_ntlmssp_start(gensec_security);
 275         NT_STATUS_NOT_OK_RETURN(nt_status);
 276
 277         gensec_ntlmssp =
 278                 talloc_get_type_abort(gensec_security->private_data,
 279                                       struct gensec_ntlmssp_context);
 280
 281         ntlmssp_state = talloc_zero(gensec_ntlmssp,
 282                                     struct ntlmssp_state);
 283         if (!ntlmssp_state) {
 284                 return NT_STATUS_NO_MEMORY;
 285         }
 286         gensec_ntlmssp->ntlmssp_state = ntlmssp_state;
 287
 288         ntlmssp_state->callback_private = gensec_ntlmssp;
 289
 290         ntlmssp_state->role = NTLMSSP_SERVER;
 291
 292         ntlmssp_state->expected_state = NTLMSSP_NEGOTIATE;
 293
 294         if (lpcfg_lanman_auth(gensec_security->settings->lp_ctx) &&
 295             gensec_setting_bool(gensec_security->settings,
 296                                 "ntlmssp_server", "allow_lm_key", false))
 297         {
 298                 ntlmssp_state->allow_lm_key = true;
 299         }
 300
 301         ntlmssp_state->neg_flags =
 302                 NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_VERSION;
 303
 304         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_server", "128bit", true)) {
 305                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 306         }
 307
 308         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_server", "56bit", true)) {
 309                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 310         }
 311
 312         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_server", "keyexchange", true)) {
 313                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 314         }
 315
 316         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_server", "alwayssign", true)) {
 317                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 318         }
 319
 320         if (gensec_setting_bool(gensec_security->settings, "ntlmssp_server", "ntlm2", true)) {
 321                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 322         }
 323
 324         if (gensec_security->want_features & GENSEC_FEATURE_SESSION_KEY) {
 325                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 326         }
 327         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 328                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 329         }
 330         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 331                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 332                 ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 333         }
 334
 335         ntlmssp_state->get_challenge = auth_ntlmssp_get_challenge;
 336         ntlmssp_state->may_set_challenge = auth_ntlmssp_may_set_challenge;
 337         ntlmssp_state->set_challenge = auth_ntlmssp_set_challenge;
 338         ntlmssp_state->check_password = auth_ntlmssp_check_password;
 339
 340         if (lpcfg_server_role(gensec_security->settings->lp_ctx) == ROLE_STANDALONE) {
 341                 ntlmssp_state->server.is_standalone = true;
 342         } else {
 343                 ntlmssp_state->server.is_standalone = false;
 344         }
 345
 346         if (gensec_security->settings->server_netbios_name) {
 347                 netbios_name = gensec_security->settings->server_netbios_name;
 348         } else {
 349                 netbios_name = lpcfg_netbios_name(gensec_security->settings->lp_ctx);
 350         }
 351
 352         if (gensec_security->settings->server_netbios_domain) {
 353                 netbios_domain = gensec_security->settings->server_netbios_domain;
 354         } else {
 355                 netbios_domain = lpcfg_workgroup(gensec_security->settings->lp_ctx);
 356         }
 357
 358         if (gensec_security->settings->server_dns_name) {
 359                 dns_name = gensec_security->settings->server_dns_name;
 360         } else {
 361                 const char *dnsdomain = lpcfg_dnsdomain(gensec_security->settings->lp_ctx);
 362                 char *lower_netbiosname;
 363
 364                 lower_netbiosname = strlower_talloc(ntlmssp_state, netbios_name);
 365                 NT_STATUS_HAVE_NO_MEMORY(lower_netbiosname);
 366
 367                 /* Find out the DNS host name */
 368                 if (dnsdomain && dnsdomain[0] != '\0') {
 369                         dns_name = talloc_asprintf(ntlmssp_state, "%s.%s",
 370                                                    lower_netbiosname,
 371                                                    dnsdomain);
 372                         talloc_free(lower_netbiosname);
 373                         NT_STATUS_HAVE_NO_MEMORY(dns_name);
 374                 } else {
 375                         dns_name = lower_netbiosname;
 376                 }
 377         }
 378
 379         if (gensec_security->settings->server_dns_domain) {
 380                 dns_domain = gensec_security->settings->server_dns_domain;
 381         } else {
 382                 dns_domain = lpcfg_dnsdomain(gensec_security->settings->lp_ctx);
 383         }
 384
 385         ntlmssp_state->server.netbios_name = talloc_strdup(ntlmssp_state, netbios_name);
 386         NT_STATUS_HAVE_NO_MEMORY(ntlmssp_state->server.netbios_name);
 387
 388         ntlmssp_state->server.netbios_domain = talloc_strdup(ntlmssp_state, netbios_domain);
 389         NT_STATUS_HAVE_NO_MEMORY(ntlmssp_state->server.netbios_domain);
 390
 391         ntlmssp_state->server.dns_name = talloc_strdup(ntlmssp_state, dns_name);
 392         NT_STATUS_HAVE_NO_MEMORY(ntlmssp_state->server.dns_name);
 393
 394         ntlmssp_state->server.dns_domain = talloc_strdup(ntlmssp_state, dns_domain);
 395         NT_STATUS_HAVE_NO_MEMORY(ntlmssp_state->server.dns_domain);
 396
 397         return NT_STATUS_OK;
 398 }
 399