source3/smbd/smb2_sesssetup.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6    Copyright (C) Jeremy Allison 2010
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "smbd/smbd.h"
  24 #include "smbd/globals.h"
  25 #include "../libcli/smb/smb_common.h"
  26 #include "../auth/gensec/gensec.h"
  27 #include "auth.h"
  28 #include "../lib/tsocket/tsocket.h"
  29 #include "../libcli/security/security.h"
  30
  31 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *smb2req,
  32                                         uint64_t in_session_id,
  33                                         uint8_t in_security_mode,
  34                                         DATA_BLOB in_security_buffer,
  35                                         uint16_t *out_session_flags,
  36                                         DATA_BLOB *out_security_buffer,
  37                                         uint64_t *out_session_id);
  38
  39 NTSTATUS smbd_smb2_request_process_sesssetup(struct smbd_smb2_request *smb2req)
  40 {
  41         const uint8_t *inhdr;
  42         const uint8_t *inbody;
  43         int i = smb2req->current_idx;
  44         uint8_t *outhdr;
  45         DATA_BLOB outbody;
  46         DATA_BLOB outdyn;
  47         uint64_t in_session_id;
  48         uint8_t in_security_mode;
  49         uint16_t in_security_offset;
  50         uint16_t in_security_length;
  51         DATA_BLOB in_security_buffer;
  52         uint16_t out_session_flags;
  53         uint64_t out_session_id;
  54         uint16_t out_security_offset;
  55         DATA_BLOB out_security_buffer = data_blob_null;
  56         NTSTATUS status;
  57
  58         status = smbd_smb2_request_verify_sizes(smb2req, 0x19);
  59         if (!NT_STATUS_IS_OK(status)) {
  60                 return smbd_smb2_request_error(smb2req, status);
  61         }
  62         inhdr = (const uint8_t *)smb2req->in.vector[i+0].iov_base;
  63         inbody = (const uint8_t *)smb2req->in.vector[i+1].iov_base;
  64
  65         in_security_offset = SVAL(inbody, 0x0C);
  66         in_security_length = SVAL(inbody, 0x0E);
  67
  68         if (in_security_offset != (SMB2_HDR_BODY + smb2req->in.vector[i+1].iov_len)) {
  69                 return smbd_smb2_request_error(smb2req, NT_STATUS_INVALID_PARAMETER);
  70         }
  71
  72         if (in_security_length > smb2req->in.vector[i+2].iov_len) {
  73                 return smbd_smb2_request_error(smb2req, NT_STATUS_INVALID_PARAMETER);
  74         }
  75
  76         in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
  77         in_security_mode = CVAL(inbody, 0x03);
  78         in_security_buffer.data = (uint8_t *)smb2req->in.vector[i+2].iov_base;
  79         in_security_buffer.length = in_security_length;
  80
  81         status = smbd_smb2_session_setup(smb2req,
  82                                          in_session_id,
  83                                          in_security_mode,
  84                                          in_security_buffer,
  85                                          &out_session_flags,
  86                                          &out_security_buffer,
  87                                          &out_session_id);
  88         if (!NT_STATUS_IS_OK(status) &&
  89             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  90                 status = nt_status_squash(status);
  91                 return smbd_smb2_request_error(smb2req, status);
  92         }
  93
  94         out_security_offset = SMB2_HDR_BODY + 0x08;
  95
  96         outhdr = (uint8_t *)smb2req->out.vector[i].iov_base;
  97
  98         outbody = data_blob_talloc(smb2req->out.vector, NULL, 0x08);
  99         if (outbody.data == NULL) {
 100                 return smbd_smb2_request_error(smb2req, NT_STATUS_NO_MEMORY);
 101         }
 102
 103         SBVAL(outhdr, SMB2_HDR_SESSION_ID, out_session_id);
 104
 105         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 106         SSVAL(outbody.data, 0x02,
 107               out_session_flags);               /* session flags */
 108         SSVAL(outbody.data, 0x04,
 109               out_security_offset);             /* security buffer offset */
 110         SSVAL(outbody.data, 0x06,
 111               out_security_buffer.length);      /* security buffer length */
 112
 113         outdyn = out_security_buffer;
 114
 115         return smbd_smb2_request_done_ex(smb2req, status, outbody, &outdyn,
 116                                          __location__);
 117 }
 118
 119 static int smbd_smb2_session_destructor(struct smbd_smb2_session *session)
 120 {
 121         if (session->sconn == NULL) {
 122                 return 0;
 123         }
 124
 125         file_close_user(session->sconn, session->vuid);
 126
 127         /* first free all tcons */
 128         while (session->tcons.list) {
 129                 talloc_free(session->tcons.list);
 130         }
 131
 132         idr_remove(session->sconn->smb2.sessions.idtree, session->vuid);
 133         DLIST_REMOVE(session->sconn->smb2.sessions.list, session);
 134         invalidate_vuid(session->sconn, session->vuid);
 135
 136         session->vuid = 0;
 137         session->status = NT_STATUS_USER_SESSION_DELETED;
 138         session->sconn = NULL;
 139
 140         return 0;
 141 }
 142
 143 static NTSTATUS smbd_smb2_auth_generic_return(struct smbd_smb2_session *session,
 144                                         struct smbd_smb2_request *smb2req,
 145                                         uint8_t in_security_mode,
 146                                         DATA_BLOB in_security_buffer,
 147                                         uint16_t *out_session_flags,
 148                                         uint64_t *out_session_id)
 149 {
 150         bool guest = false;
 151
 152         if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
 153             lp_server_signing() == SMB_SIGNING_REQUIRED) {
 154                 session->do_signing = true;
 155         }
 156
 157         if (security_session_user_level(session->session_info, NULL) < SECURITY_USER) {
 158                 /* we map anonymous to guest internally */
 159                 *out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
 160                 *out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
 161                 /* force no signing */
 162                 session->do_signing = false;
 163                 guest = true;
 164         }
 165
 166         session->session_key = session->session_info->session_key;
 167
 168         session->compat_vuser = talloc_zero(session, user_struct);
 169         if (session->compat_vuser == NULL) {
 170                 TALLOC_FREE(session);
 171                 return NT_STATUS_NO_MEMORY;
 172         }
 173         session->compat_vuser->gensec_security = session->gensec_security;
 174         session->compat_vuser->homes_snum = -1;
 175         session->compat_vuser->session_info = session->session_info;
 176         session->compat_vuser->session_keystr = NULL;
 177         session->compat_vuser->vuid = session->vuid;
 178         DLIST_ADD(session->sconn->users, session->compat_vuser);
 179         session->sconn->num_users++;
 180
 181         if (security_session_user_level(session->session_info, NULL) >= SECURITY_USER) {
 182                 session->compat_vuser->homes_snum =
 183                         register_homes_share(session->session_info->unix_info->unix_name);
 184         }
 185
 186         if (!session_claim(session->sconn, session->compat_vuser)) {
 187                 DEBUG(1, ("smb2: Failed to claim session "
 188                         "for vuid=%d\n",
 189                         session->compat_vuser->vuid));
 190                 TALLOC_FREE(session);
 191                 return NT_STATUS_LOGON_FAILURE;
 192         }
 193
 194         set_current_user_info(session->session_info->unix_info->sanitized_username,
 195                               session->session_info->unix_info->unix_name,
 196                               session->session_info->info->domain_name);
 197
 198         reload_services(smb2req->sconn, conn_snum_used, true);
 199
 200         session->status = NT_STATUS_OK;
 201
 202         /*
 203          * we attach the session to the request
 204          * so that the response can be signed
 205          */
 206         smb2req->session = session;
 207         if (!guest) {
 208                 smb2req->do_signing = true;
 209         }
 210
 211         global_client_caps |= (CAP_LEVEL_II_OPLOCKS|CAP_STATUS32);
 212
 213         *out_session_id = session->vuid;
 214
 215         return NT_STATUS_OK;
 216 }
 217
 218 static NTSTATUS smbd_smb2_auth_generic(struct smbd_smb2_session *session,
 219                                        struct smbd_smb2_request *smb2req,
 220                                        uint8_t in_security_mode,
 221                                        DATA_BLOB in_security_buffer,
 222                                        uint16_t *out_session_flags,
 223                                        DATA_BLOB *out_security_buffer,
 224                                        uint64_t *out_session_id)
 225 {
 226         NTSTATUS status;
 227
 228         *out_security_buffer = data_blob_null;
 229
 230         if (session->gensec_security == NULL) {
 231                 status = auth_generic_prepare(session, session->sconn->remote_address,
 232                                             &session->gensec_security);
 233                 if (!NT_STATUS_IS_OK(status)) {
 234                         TALLOC_FREE(session);
 235                         return status;
 236                 }
 237
 238                 gensec_want_feature(session->gensec_security, GENSEC_FEATURE_SESSION_KEY);
 239                 gensec_want_feature(session->gensec_security, GENSEC_FEATURE_UNIX_TOKEN);
 240
 241                 status = gensec_start_mech_by_oid(session->gensec_security, GENSEC_OID_SPNEGO);
 242                 if (!NT_STATUS_IS_OK(status)) {
 243                         TALLOC_FREE(session);
 244                         return status;
 245                 }
 246         }
 247
 248         become_root();
 249         status = gensec_update(session->gensec_security,
 250                                smb2req, NULL,
 251                                in_security_buffer,
 252                                out_security_buffer);
 253         unbecome_root();
 254         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 255             !NT_STATUS_IS_OK(status)) {
 256                 TALLOC_FREE(session);
 257                 return nt_status_squash(status);
 258         }
 259
 260         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 261                 *out_session_id = session->vuid;
 262                 return status;
 263         }
 264
 265         status = gensec_session_info(session->gensec_security,
 266                                      session,
 267                                      &session->session_info);
 268
 269         if (!NT_STATUS_IS_OK(status)) {
 270                 TALLOC_FREE(session);
 271                 return status;
 272         }
 273         *out_session_id = session->vuid;
 274
 275         return smbd_smb2_auth_generic_return(session,
 276                                              smb2req,
 277                                              in_security_mode,
 278                                              in_security_buffer,
 279                                              out_session_flags,
 280                                              out_session_id);
 281 }
 282
 283 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *smb2req,
 284                                         uint64_t in_session_id,
 285                                         uint8_t in_security_mode,
 286                                         DATA_BLOB in_security_buffer,
 287                                         uint16_t *out_session_flags,
 288                                         DATA_BLOB *out_security_buffer,
 289                                         uint64_t *out_session_id)
 290 {
 291         struct smbd_smb2_session *session;
 292
 293         *out_session_flags = 0;
 294         *out_session_id = 0;
 295
 296         if (in_session_id == 0) {
 297                 int id;
 298
 299                 /* create a new session */
 300                 session = talloc_zero(smb2req->sconn, struct smbd_smb2_session);
 301                 if (session == NULL) {
 302                         return NT_STATUS_NO_MEMORY;
 303                 }
 304                 session->status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 305                 id = idr_get_new_random(smb2req->sconn->smb2.sessions.idtree,
 306                                         session,
 307                                         smb2req->sconn->smb2.sessions.limit);
 308                 if (id == -1) {
 309                         return NT_STATUS_INSUFFICIENT_RESOURCES;
 310                 }
 311                 session->vuid = id;
 312
 313                 session->tcons.idtree = idr_init(session);
 314                 if (session->tcons.idtree == NULL) {
 315                         return NT_STATUS_NO_MEMORY;
 316                 }
 317                 session->tcons.limit = 0x0000FFFE;
 318                 session->tcons.list = NULL;
 319
 320                 DLIST_ADD_END(smb2req->sconn->smb2.sessions.list, session,
 321                               struct smbd_smb2_session *);
 322                 session->sconn = smb2req->sconn;
 323                 talloc_set_destructor(session, smbd_smb2_session_destructor);
 324         } else {
 325                 void *p;
 326
 327                 /* lookup an existing session */
 328                 p = idr_find(smb2req->sconn->smb2.sessions.idtree, in_session_id);
 329                 if (p == NULL) {
 330                         return NT_STATUS_USER_SESSION_DELETED;
 331                 }
 332                 session = talloc_get_type_abort(p, struct smbd_smb2_session);
 333         }
 334
 335         if (NT_STATUS_IS_OK(session->status)) {
 336                 return NT_STATUS_REQUEST_NOT_ACCEPTED;
 337         }
 338
 339         return smbd_smb2_auth_generic(session,
 340                                       smb2req,
 341                                       in_security_mode,
 342                                       in_security_buffer,
 343                                       out_session_flags,
 344                                       out_security_buffer,
 345                                       out_session_id);
 346 }
 347
 348 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
 349 {
 350         NTSTATUS status;
 351         DATA_BLOB outbody;
 352
 353         status = smbd_smb2_request_verify_sizes(req, 0x04);
 354         if (!NT_STATUS_IS_OK(status)) {
 355                 return smbd_smb2_request_error(req, status);
 356         }
 357
 358         /*
 359          * TODO: cancel all outstanding requests on the session
 360          *       and delete all tree connections.
 361          */
 362         smbd_smb2_session_destructor(req->session);
 363         /*
 364          * we may need to sign the response, so we need to keep
 365          * the session until the response is sent to the wire.
 366          */
 367         talloc_steal(req, req->session);
 368
 369         outbody = data_blob_talloc(req->out.vector, NULL, 0x04);
 370         if (outbody.data == NULL) {
 371                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 372         }
 373
 374         SSVAL(outbody.data, 0x00, 0x04);        /* struct size */
 375         SSVAL(outbody.data, 0x02, 0);           /* reserved */
 376
 377         return smbd_smb2_request_done(req, outbody, NULL);
 378 }