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
 182                 smbcli_transport_simple_set_signing(session->transport, session_key,
 183                                                     state->setup.nt1.in.password2);
 184                 set_user_session_key(session, &session_key);
 185
 186                 data_blob_free(&session_key);
 187         } else if (lp_client_plaintext_auth()) {
 188                 state->setup.nt1.in.password1 = data_blob_talloc(state, password, strlen(password));
 189                 state->setup.nt1.in.password2 = data_blob(NULL, 0);
 190         } else {
 191                 /* could match windows client and return 'cannot logon from this workstation', but it just confuses everybody */
 192                 return NT_STATUS_INVALID_PARAMETER;
 193         }
 194
 195         *req = smb_raw_sesssetup_send(session, &state->setup);
 196         if (!*req) {
 197                 return NT_STATUS_NO_MEMORY;
 198         }
 199         return (*req)->status;
 200 }
 201
 202
 203 /*
 204   old style session setup (pre NT1 protocol level)
 205 */
 206 static NTSTATUS session_setup_old(struct composite_context *c,
 207                                   struct smbcli_session *session,
 208                                   struct smb_composite_sesssetup *io,
 209                                   struct smbcli_request **req)
 210 {
 211         NTSTATUS nt_status;
 212         struct sesssetup_state *state = talloc_get_type(c->private_data, struct sesssetup_state);
 213         const char *password = cli_credentials_get_password(io->in.credentials);
 214         DATA_BLOB names_blob = NTLMv2_generate_names_blob(state, session->transport->socket->hostname, lp_workgroup());
 215         DATA_BLOB session_key;
 216         int flags = 0;
 217         if (lp_client_lanman_auth()) {
 218                 flags |= CLI_CRED_LANMAN_AUTH;
 219         }
 220
 221         if (lp_client_ntlmv2_auth()) {
 222                 flags |= CLI_CRED_NTLMv2_AUTH;
 223         }
 224
 225         state->setup.old.level      = RAW_SESSSETUP_OLD;
 226         state->setup.old.in.bufsize = session->transport->options.max_xmit;
 227         state->setup.old.in.mpx_max = session->transport->options.max_mux;
 228         state->setup.old.in.vc_num  = 1;
 229         state->setup.old.in.sesskey = io->in.sesskey;
 230         state->setup.old.in.os      = "Unix";
 231         state->setup.old.in.lanman  = talloc_asprintf(state, "Samba %s", SAMBA_VERSION_STRING);
 232         cli_credentials_get_ntlm_username_domain(io->in.credentials, state,
 233                                                  &state->setup.old.in.user,
 234                                                  &state->setup.old.in.domain);
 235
 236         if (session->transport->negotiate.sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) {
 237                 nt_status = cli_credentials_get_ntlm_response(io->in.credentials, state,
 238                                                               &flags,
 239                                                               session->transport->negotiate.secblob,
 240                                                               names_blob,
 241                                                               &state->setup.old.in.password,
 242                                                               NULL,
 243                                                               NULL, &session_key);
 244                 set_user_session_key(session, &session_key);
 245
 246                 data_blob_free(&session_key);
 247         } else if (lp_client_plaintext_auth()) {
 248                 state->setup.old.in.password = data_blob_talloc(state, password, strlen(password));
 249         } else {
 250                 /* could match windows client and return 'cannot logon from this workstation', but it just confuses everybody */
 251                 return NT_STATUS_INVALID_PARAMETER;
 252         }
 253
 254         *req = smb_raw_sesssetup_send(session, &state->setup);
 255         if (!*req) {
 256                 return NT_STATUS_NO_MEMORY;
 257         }
 258         return (*req)->status;
 259 }
 260
 261
 262 /*
 263   Modern, all singing, all dancing extended security (and possibly SPNEGO) request
 264 */
 265 static NTSTATUS session_setup_spnego(struct composite_context *c,
 266                                      struct smbcli_session *session,
 267                                      struct smb_composite_sesssetup *io,
 268                                      struct smbcli_request **req)
 269 {
 270         struct sesssetup_state *state = talloc_get_type(c->private_data, struct sesssetup_state);
 271         NTSTATUS status, session_key_err;
 272         DATA_BLOB session_key = data_blob(NULL, 0);
 273         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 274         const char *chosen_oid = NULL;
 275
 276         state->setup.spnego.level           = RAW_SESSSETUP_SPNEGO;
 277         state->setup.spnego.in.bufsize      = session->transport->options.max_xmit;
 278         state->setup.spnego.in.mpx_max      = session->transport->options.max_mux;
 279         state->setup.spnego.in.vc_num       = 1;
 280         state->setup.spnego.in.sesskey      = io->in.sesskey;
 281         state->setup.spnego.in.capabilities = io->in.capabilities;
 282         state->setup.spnego.in.os           = "Unix";
 283         state->setup.spnego.in.lanman       = talloc_asprintf(state, "Samba %s", SAMBA_VERSION_STRING);
 284         state->setup.spnego.in.workgroup    = io->in.workgroup;
 285
 286         state->setup.spnego.out.vuid        = session->vuid;
 287
 288         smbcli_temp_set_signing(session->transport);
 289
 290         status = gensec_client_start(session, &session->gensec, c->event_ctx);
 291         if (!NT_STATUS_IS_OK(status)) {
 292                 DEBUG(1, ("Failed to start GENSEC client mode: %s\n", nt_errstr(status)));
 293                 return status;
 294         }
 295
 296         gensec_want_feature(session->gensec, GENSEC_FEATURE_SESSION_KEY);
 297
 298         status = gensec_set_credentials(session->gensec, io->in.credentials);
 299         if (!NT_STATUS_IS_OK(status)) {
 300                 DEBUG(1, ("Failed to start set GENSEC client credentails: %s\n",
 301                           nt_errstr(status)));
 302                 return status;
 303         }
 304
 305         status = gensec_set_target_hostname(session->gensec, session->transport->socket->hostname);
 306         if (!NT_STATUS_IS_OK(status)) {
 307                 DEBUG(1, ("Failed to start set GENSEC target hostname: %s\n",
 308                           nt_errstr(status)));
 309                 return status;
 310         }
 311
 312         status = gensec_set_target_service(session->gensec, "cifs");
 313         if (!NT_STATUS_IS_OK(status)) {
 314                 DEBUG(1, ("Failed to start set GENSEC target service: %s\n",
 315                           nt_errstr(status)));
 316                 return status;
 317         }
 318
 319         if (session->transport->negotiate.secblob.length) {
 320                 chosen_oid = GENSEC_OID_SPNEGO;
 321                 status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 322                 if (!NT_STATUS_IS_OK(status)) {
 323                         DEBUG(1, ("Failed to start set GENSEC client mechanism %s: %s\n",
 324                                   gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 325                         chosen_oid = GENSEC_OID_NTLMSSP;
 326                         status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 327                         if (!NT_STATUS_IS_OK(status)) {
 328                                 DEBUG(1, ("Failed to start set (fallback) GENSEC client mechanism %s: %s\n",
 329                                           gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 330                         return status;
 331                         }
 332                 }
 333         } else {
 334                 /* without a sec blob, means raw NTLMSSP */
 335                 chosen_oid = GENSEC_OID_NTLMSSP;
 336                 status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 337                 if (!NT_STATUS_IS_OK(status)) {
 338                         DEBUG(1, ("Failed to start set GENSEC client mechanism %s: %s\n",
 339                                   gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 340                 }
 341         }
 342
 343         if (chosen_oid == GENSEC_OID_SPNEGO) {
 344                 status = gensec_update(session->gensec, state,
 345                                        session->transport->negotiate.secblob,
 346                                        &state->setup.spnego.in.secblob);
 347         } else {
 348                 status = gensec_update(session->gensec, state,
 349                                        data_blob(NULL, 0),
 350                                        &state->setup.spnego.in.secblob);
 351
 352         }
 353
 354         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 355             !NT_STATUS_IS_OK(status)) {
 356                 DEBUG(1, ("Failed initial gensec_update with mechanism %s: %s\n",
 357                           gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 358                 return status;
 359         }
 360         state->gensec_status = status;
 361
 362         session_key_err = gensec_session_key(session->gensec, &session_key);
 363         if (NT_STATUS_IS_OK(session_key_err)) {
 364                 smbcli_transport_simple_set_signing(session->transport, session_key, null_data_blob);
 365         }
 366
 367         *req = smb_raw_sesssetup_send(session, &state->setup);
 368         if (!*req) {
 369                 return NT_STATUS_NO_MEMORY;
 370         }
 371         return (*req)->status;
 372 }
 373
 374
 375 /*
 376   composite session setup function that hides the details of all the
 377   different session setup varients, including the multi-pass nature of
 378   the spnego varient
 379 */
 380 struct composite_context *smb_composite_sesssetup_send(struct smbcli_session *session,
 381                                                        struct smb_composite_sesssetup *io)
 382 {
 383         struct composite_context *c;
 384         struct sesssetup_state *state;
 385         NTSTATUS status;
 386
 387         c = talloc_zero(session, struct composite_context);
 388         if (c == NULL) return NULL;
 389
 390         state = talloc(c, struct sesssetup_state);
 391         if (state == NULL) {
 392                 talloc_free(c);
 393                 return NULL;
 394         }
 395
 396         state->io = io;
 397
 398         c->state = COMPOSITE_STATE_IN_PROGRESS;
 399         c->private_data = state;
 400         c->event_ctx = session->transport->socket->event.ctx;
 401
 402         /* no session setup at all in earliest protocol varients */
 403         if (session->transport->negotiate.protocol < PROTOCOL_LANMAN1) {
 404                 ZERO_STRUCT(io->out);
 405                 c->state = COMPOSITE_STATE_DONE;
 406                 return c;
 407         }
 408
 409         /* see what session setup interface we will use */
 410         if (session->transport->negotiate.protocol < PROTOCOL_NT1) {
 411                 status = session_setup_old(c, session, io, &state->req);
 412         } else if (!session->transport->options.use_spnego ||
 413                    !(io->in.capabilities & CAP_EXTENDED_SECURITY)) {
 414                 status = session_setup_nt1(c, session, io, &state->req);
 415         } else {
 416                 status = session_setup_spnego(c, session, io, &state->req);
 417         }
 418
 419         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) ||
 420             NT_STATUS_IS_OK(status)) {
 421                 state->req->async.fn = request_handler;
 422                 state->req->async.private = c;
 423                 return c;
 424         }
 425
 426         c->state = COMPOSITE_STATE_ERROR;
 427         c->status = status;
 428         return c;
 429 }
 430
 431
 432 /*
 433   receive a composite session setup reply
 434 */
 435 NTSTATUS smb_composite_sesssetup_recv(struct composite_context *c)
 436 {
 437         NTSTATUS status;
 438         status = composite_wait(c);
 439         talloc_free(c);
 440         return status;
 441 }
 442
 443 /*
 444   sync version of smb_composite_sesssetup
 445 */
 446 NTSTATUS smb_composite_sesssetup(struct smbcli_session *session, struct smb_composite_sesssetup *io)
 447 {
 448         struct composite_context *c = smb_composite_sesssetup_send(session, io);
 449         return smb_composite_sesssetup_recv(c);
 450 }