source4/libcli/smb_composite/sesssetup.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Andrew Tridgell 2005
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20 /*
  21   a composite API for making handling a generic async session setup
  22 */
  23
  24 #include "includes.h"
  25 #include "libcli/raw/libcliraw.h"
  26 #include "libcli/composite/composite.h"
  27 #include "libcli/smb_composite/smb_composite.h"
  28 #include "libcli/auth/libcli_auth.h"
  29 #include "auth/auth.h"
  30 #include "version.h"
  31
  32 struct sesssetup_state {
  33         union smb_sesssetup setup;
  34         NTSTATUS gensec_status;
  35         struct smb_composite_sesssetup *io;
  36         struct smbcli_request *req;
  37 };
  38
  39
  40 /*
  41   store the user session key for a transport
  42 */
  43 static void set_user_session_key(struct smbcli_session *session,
  44                                  const DATA_BLOB *session_key)
  45 {
  46         session->user_session_key = data_blob_talloc(session,
  47                                                      session_key->data,
  48                                                      session_key->length);
  49 }
  50
  51 /*
  52   handler for completion of a smbcli_request sub-request
  53 */
  54 static void request_handler(struct smbcli_request *req)
  55 {
  56         struct composite_context *c = req->async.private;
  57         struct sesssetup_state *state = talloc_get_type(c->private_data, struct sesssetup_state);
  58         struct smbcli_session *session = req->session;
  59         DATA_BLOB session_key = data_blob(NULL, 0);
  60         DATA_BLOB null_data_blob = data_blob(NULL, 0);
  61         NTSTATUS session_key_err;
  62
  63         c->status = smb_raw_sesssetup_recv(req, state, &state->setup);
  64
  65         switch (state->setup.old.level) {
  66         case RAW_SESSSETUP_OLD:
  67                 state->io->out.vuid = state->setup.old.out.vuid;
  68                 break;
  69
  70         case RAW_SESSSETUP_NT1:
  71                 state->io->out.vuid = state->setup.nt1.out.vuid;
  72                 break;
  73
  74         case RAW_SESSSETUP_SPNEGO:
  75                 session->vuid = state->io->out.vuid = state->setup.spnego.out.vuid;
  76                 if (!NT_STATUS_EQUAL(c->status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
  77                     !NT_STATUS_IS_OK(c->status)) {
  78                         break;
  79                 }
  80                 if (NT_STATUS_EQUAL(state->gensec_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  81
  82                         /* The status value here, from the earlier pass at GENSEC is
  83                          * vital to the security of the system.  Even if the other end
  84                          * accepts, if GENSEC claims 'MORE_PROCESSING_REQUIRED' then
  85                          * you must keep feeding it blobs, or else the remote
  86                          * host/attacker might avoid mutal authentication
  87                          * requirements */
  88
  89                         state->gensec_status = gensec_update(session->gensec, state,
  90                                                          state->setup.spnego.out.secblob,
  91                                                          &state->setup.spnego.in.secblob);
  92                         c->status = state->gensec_status;
  93                         if (!NT_STATUS_EQUAL(c->status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
  94                             !NT_STATUS_IS_OK(c->status)) {
  95                                 break;
  96                         }
  97                 } else {
  98                         state->setup.spnego.in.secblob = data_blob(NULL, 0);
  99                 }
 100
 101                 /* we need to do another round of session setup. We keep going until both sides
 102                    are happy */
 103                 session_key_err = gensec_session_key(session->gensec, &session_key);
 104                 if (NT_STATUS_IS_OK(session_key_err)) {
 105                         set_user_session_key(session, &session_key);
 106                         smbcli_transport_simple_set_signing(session->transport, session_key, null_data_blob);
 107                 }
 108
 109                 if (state->setup.spnego.in.secblob.length) {
 110                         state->req = smb_raw_sesssetup_send(session, &state->setup);
 111                         state->req->async.fn = request_handler;
 112                         state->req->async.private = c;
 113                         return;
 114                 }
 115         }
 116
 117         /* enforce the local signing required flag */
 118         if (NT_STATUS_IS_OK(c->status) && !cli_credentials_is_anonymous(state->io->in.credentials)) {
 119                 if (!session->transport->negotiate.sign_info.doing_signing
 120                     && session->transport->negotiate.sign_info.mandatory_signing) {
 121                         DEBUG(0, ("SMB signing required, but server does not support it\n"));
 122                         c->status = NT_STATUS_ACCESS_DENIED;
 123                 }
 124         }
 125
 126         if (NT_STATUS_IS_OK(c->status)) {
 127                 c->state = COMPOSITE_STATE_DONE;
 128         } else {
 129                 c->state = COMPOSITE_STATE_ERROR;
 130         }
 131         if (c->async.fn) {
 132                 c->async.fn(c);
 133         }
 134 }
 135
 136
 137 /*
 138   send a nt1 style session setup
 139 */
 140 static NTSTATUS session_setup_nt1(struct composite_context *c,
 141                                   struct smbcli_session *session,
 142                                   struct smb_composite_sesssetup *io,
 143                                   struct smbcli_request **req)
 144 {
 145         NTSTATUS nt_status;
 146         struct sesssetup_state *state = talloc_get_type(c->private_data, struct sesssetup_state);
 147         const char *password = cli_credentials_get_password(io->in.credentials);
 148         DATA_BLOB names_blob = NTLMv2_generate_names_blob(state, session->transport->socket->hostname, lp_workgroup());
 149         DATA_BLOB session_key;
 150         int flags = CLI_CRED_NTLM_AUTH;
 151         if (lp_client_lanman_auth()) {
 152                 flags |= CLI_CRED_LANMAN_AUTH;
 153         }
 154
 155         if (lp_client_ntlmv2_auth()) {
 156                 flags |= CLI_CRED_NTLMv2_AUTH;
 157         }
 158
 159         state->setup.nt1.level           = RAW_SESSSETUP_NT1;
 160         state->setup.nt1.in.bufsize      = session->transport->options.max_xmit;
 161         state->setup.nt1.in.mpx_max      = session->transport->options.max_mux;
 162         state->setup.nt1.in.vc_num       = 1;
 163         state->setup.nt1.in.sesskey      = io->in.sesskey;
 164         state->setup.nt1.in.capabilities = io->in.capabilities;
 165         state->setup.nt1.in.os           = "Unix";
 166         state->setup.nt1.in.lanman       = talloc_asprintf(state, "Samba %s", SAMBA_VERSION_STRING);
 167
 168         cli_credentials_get_ntlm_username_domain(io->in.credentials, state,
 169                                                  &state->setup.nt1.in.user,
 170                                                  &state->setup.nt1.in.domain);
 171
 172
 173         if (session->transport->negotiate.sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) {
 174                 nt_status = cli_credentials_get_ntlm_response(io->in.credentials, state,
 175                                                               &flags,
 176                                                               session->transport->negotiate.secblob,
 177                                                               names_blob,
 178                                                               &state->setup.nt1.in.password1,
 179                                                               &state->setup.nt1.in.password2,
 180                                                               NULL, &session_key);
 181                 NT_STATUS_NOT_OK_RETURN(nt_status);
 182
 183                 smbcli_transport_simple_set_signing(session->transport, session_key,
 184                                                     state->setup.nt1.in.password2);
 185                 set_user_session_key(session, &session_key);
 186
 187                 data_blob_free(&session_key);
 188         } else if (lp_client_plaintext_auth()) {
 189                 state->setup.nt1.in.password1 = data_blob_talloc(state, password, strlen(password));
 190                 state->setup.nt1.in.password2 = data_blob(NULL, 0);
 191         } else {
 192                 /* could match windows client and return 'cannot logon from this workstation', but it just confuses everybody */
 193                 return NT_STATUS_INVALID_PARAMETER;
 194         }
 195
 196         *req = smb_raw_sesssetup_send(session, &state->setup);
 197         if (!*req) {
 198                 return NT_STATUS_NO_MEMORY;
 199         }
 200         return (*req)->status;
 201 }
 202
 203
 204 /*
 205   old style session setup (pre NT1 protocol level)
 206 */
 207 static NTSTATUS session_setup_old(struct composite_context *c,
 208                                   struct smbcli_session *session,
 209                                   struct smb_composite_sesssetup *io,
 210                                   struct smbcli_request **req)
 211 {
 212         NTSTATUS nt_status;
 213         struct sesssetup_state *state = talloc_get_type(c->private_data, struct sesssetup_state);
 214         const char *password = cli_credentials_get_password(io->in.credentials);
 215         DATA_BLOB names_blob = NTLMv2_generate_names_blob(state, session->transport->socket->hostname, lp_workgroup());
 216         DATA_BLOB session_key;
 217         int flags = 0;
 218         if (lp_client_lanman_auth()) {
 219                 flags |= CLI_CRED_LANMAN_AUTH;
 220         }
 221
 222         if (lp_client_ntlmv2_auth()) {
 223                 flags |= CLI_CRED_NTLMv2_AUTH;
 224         }
 225
 226         state->setup.old.level      = RAW_SESSSETUP_OLD;
 227         state->setup.old.in.bufsize = session->transport->options.max_xmit;
 228         state->setup.old.in.mpx_max = session->transport->options.max_mux;
 229         state->setup.old.in.vc_num  = 1;
 230         state->setup.old.in.sesskey = io->in.sesskey;
 231         state->setup.old.in.os      = "Unix";
 232         state->setup.old.in.lanman  = talloc_asprintf(state, "Samba %s", SAMBA_VERSION_STRING);
 233         cli_credentials_get_ntlm_username_domain(io->in.credentials, state,
 234                                                  &state->setup.old.in.user,
 235                                                  &state->setup.old.in.domain);
 236
 237         if (session->transport->negotiate.sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) {
 238                 nt_status = cli_credentials_get_ntlm_response(io->in.credentials, state,
 239                                                               &flags,
 240                                                               session->transport->negotiate.secblob,
 241                                                               names_blob,
 242                                                               &state->setup.old.in.password,
 243                                                               NULL,
 244                                                               NULL, &session_key);
 245                 NT_STATUS_NOT_OK_RETURN(nt_status);
 246                 set_user_session_key(session, &session_key);
 247
 248                 data_blob_free(&session_key);
 249         } else if (lp_client_plaintext_auth()) {
 250                 state->setup.old.in.password = data_blob_talloc(state, password, strlen(password));
 251         } else {
 252                 /* could match windows client and return 'cannot logon from this workstation', but it just confuses everybody */
 253                 return NT_STATUS_INVALID_PARAMETER;
 254         }
 255
 256         *req = smb_raw_sesssetup_send(session, &state->setup);
 257         if (!*req) {
 258                 return NT_STATUS_NO_MEMORY;
 259         }
 260         return (*req)->status;
 261 }
 262
 263
 264 /*
 265   Modern, all singing, all dancing extended security (and possibly SPNEGO) request
 266 */
 267 static NTSTATUS session_setup_spnego(struct composite_context *c,
 268                                      struct smbcli_session *session,
 269                                      struct smb_composite_sesssetup *io,
 270                                      struct smbcli_request **req)
 271 {
 272         struct sesssetup_state *state = talloc_get_type(c->private_data, struct sesssetup_state);
 273         NTSTATUS status, session_key_err;
 274         DATA_BLOB session_key = data_blob(NULL, 0);
 275         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 276         const char *chosen_oid = NULL;
 277
 278         state->setup.spnego.level           = RAW_SESSSETUP_SPNEGO;
 279         state->setup.spnego.in.bufsize      = session->transport->options.max_xmit;
 280         state->setup.spnego.in.mpx_max      = session->transport->options.max_mux;
 281         state->setup.spnego.in.vc_num       = 1;
 282         state->setup.spnego.in.sesskey      = io->in.sesskey;
 283         state->setup.spnego.in.capabilities = io->in.capabilities;
 284         state->setup.spnego.in.os           = "Unix";
 285         state->setup.spnego.in.lanman       = talloc_asprintf(state, "Samba %s", SAMBA_VERSION_STRING);
 286         state->setup.spnego.in.workgroup    = io->in.workgroup;
 287
 288         state->setup.spnego.out.vuid        = session->vuid;
 289
 290         smbcli_temp_set_signing(session->transport);
 291
 292         status = gensec_client_start(session, &session->gensec, c->event_ctx);
 293         if (!NT_STATUS_IS_OK(status)) {
 294                 DEBUG(1, ("Failed to start GENSEC client mode: %s\n", nt_errstr(status)));
 295                 return status;
 296         }
 297
 298         gensec_want_feature(session->gensec, GENSEC_FEATURE_SESSION_KEY);
 299
 300         status = gensec_set_credentials(session->gensec, io->in.credentials);
 301         if (!NT_STATUS_IS_OK(status)) {
 302                 DEBUG(1, ("Failed to start set GENSEC client credentails: %s\n",
 303                           nt_errstr(status)));
 304                 return status;
 305         }
 306
 307         status = gensec_set_target_hostname(session->gensec, session->transport->socket->hostname);
 308         if (!NT_STATUS_IS_OK(status)) {
 309                 DEBUG(1, ("Failed to start set GENSEC target hostname: %s\n",
 310                           nt_errstr(status)));
 311                 return status;
 312         }
 313
 314         status = gensec_set_target_service(session->gensec, "cifs");
 315         if (!NT_STATUS_IS_OK(status)) {
 316                 DEBUG(1, ("Failed to start set GENSEC target service: %s\n",
 317                           nt_errstr(status)));
 318                 return status;
 319         }
 320
 321         if (session->transport->negotiate.secblob.length) {
 322                 chosen_oid = GENSEC_OID_SPNEGO;
 323                 status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 324                 if (!NT_STATUS_IS_OK(status)) {
 325                         DEBUG(1, ("Failed to start set GENSEC client mechanism %s: %s\n",
 326                                   gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 327                         chosen_oid = GENSEC_OID_NTLMSSP;
 328                         status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 329                         if (!NT_STATUS_IS_OK(status)) {
 330                                 DEBUG(1, ("Failed to start set (fallback) GENSEC client mechanism %s: %s\n",
 331                                           gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 332                         return status;
 333                         }
 334                 }
 335         } else {
 336                 /* without a sec blob, means raw NTLMSSP */
 337                 chosen_oid = GENSEC_OID_NTLMSSP;
 338                 status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 339                 if (!NT_STATUS_IS_OK(status)) {
 340                         DEBUG(1, ("Failed to start set GENSEC client mechanism %s: %s\n",
 341                                   gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 342                 }
 343         }
 344
 345         if (chosen_oid == GENSEC_OID_SPNEGO) {
 346                 status = gensec_update(session->gensec, state,
 347                                        session->transport->negotiate.secblob,
 348                                        &state->setup.spnego.in.secblob);
 349         } else {
 350                 status = gensec_update(session->gensec, state,
 351                                        data_blob(NULL, 0),
 352                                        &state->setup.spnego.in.secblob);
 353
 354         }
 355
 356         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 357             !NT_STATUS_IS_OK(status)) {
 358                 DEBUG(1, ("Failed initial gensec_update with mechanism %s: %s\n",
 359                           gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 360                 return status;
 361         }
 362         state->gensec_status = status;
 363
 364         session_key_err = gensec_session_key(session->gensec, &session_key);
 365         if (NT_STATUS_IS_OK(session_key_err)) {
 366                 smbcli_transport_simple_set_signing(session->transport, session_key, null_data_blob);
 367         }
 368
 369         *req = smb_raw_sesssetup_send(session, &state->setup);
 370         if (!*req) {
 371                 return NT_STATUS_NO_MEMORY;
 372         }
 373         return (*req)->status;
 374 }
 375
 376
 377 /*
 378   composite session setup function that hides the details of all the
 379   different session setup varients, including the multi-pass nature of
 380   the spnego varient
 381 */
 382 struct composite_context *smb_composite_sesssetup_send(struct smbcli_session *session,
 383                                                        struct smb_composite_sesssetup *io)
 384 {
 385         struct composite_context *c;
 386         struct sesssetup_state *state;
 387         NTSTATUS status;
 388
 389         c = talloc_zero(session, struct composite_context);
 390         if (c == NULL) return NULL;
 391
 392         state = talloc(c, struct sesssetup_state);
 393         if (state == NULL) {
 394                 talloc_free(c);
 395                 return NULL;
 396         }
 397
 398         state->io = io;
 399
 400         c->state = COMPOSITE_STATE_IN_PROGRESS;
 401         c->private_data = state;
 402         c->event_ctx = session->transport->socket->event.ctx;
 403
 404         /* no session setup at all in earliest protocol varients */
 405         if (session->transport->negotiate.protocol < PROTOCOL_LANMAN1) {
 406                 ZERO_STRUCT(io->out);
 407                 c->state = COMPOSITE_STATE_DONE;
 408                 return c;
 409         }
 410
 411         /* see what session setup interface we will use */
 412         if (session->transport->negotiate.protocol < PROTOCOL_NT1) {
 413                 status = session_setup_old(c, session, io, &state->req);
 414         } else if (!session->transport->options.use_spnego ||
 415                    !(io->in.capabilities & CAP_EXTENDED_SECURITY)) {
 416                 status = session_setup_nt1(c, session, io, &state->req);
 417         } else {
 418                 status = session_setup_spnego(c, session, io, &state->req);
 419         }
 420
 421         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) ||
 422             NT_STATUS_IS_OK(status)) {
 423                 state->req->async.fn = request_handler;
 424                 state->req->async.private = c;
 425                 return c;
 426         }
 427
 428         c->state = COMPOSITE_STATE_ERROR;
 429         c->status = status;
 430         return c;
 431 }
 432
 433
 434 /*
 435   receive a composite session setup reply
 436 */
 437 NTSTATUS smb_composite_sesssetup_recv(struct composite_context *c)
 438 {
 439         NTSTATUS status;
 440         status = composite_wait(c);
 441         talloc_free(c);
 442         return status;
 443 }
 444
 445 /*
 446   sync version of smb_composite_sesssetup
 447 */
 448 NTSTATUS smb_composite_sesssetup(struct smbcli_session *session, struct smb_composite_sesssetup *io)
 449 {
 450         struct composite_context *c = smb_composite_sesssetup_send(session, io);
 451         return smb_composite_sesssetup_recv(c);
 452 }