source3/smbd/smb2_sesssetup.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "smbd/globals.h"
  23 #include "../libcli/smb/smb_common.h"
  24 #include "../libcli/auth/spnego.h"
  25 #include "ntlmssp.h"
  26
  27 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *req,
  28                                         uint64_t in_session_id,
  29                                         uint8_t in_security_mode,
  30                                         DATA_BLOB in_security_buffer,
  31                                         uint16_t *out_session_flags,
  32                                         DATA_BLOB *out_security_buffer,
  33                                         uint64_t *out_session_id);
  34
  35 NTSTATUS smbd_smb2_request_process_sesssetup(struct smbd_smb2_request *req)
  36 {
  37         const uint8_t *inhdr;
  38         const uint8_t *inbody;
  39         int i = req->current_idx;
  40         uint8_t *outhdr;
  41         DATA_BLOB outbody;
  42         DATA_BLOB outdyn;
  43         size_t expected_body_size = 0x19;
  44         size_t body_size;
  45         uint64_t in_session_id;
  46         uint8_t in_security_mode;
  47         uint16_t in_security_offset;
  48         uint16_t in_security_length;
  49         DATA_BLOB in_security_buffer;
  50         uint16_t out_session_flags;
  51         uint64_t out_session_id;
  52         uint16_t out_security_offset;
  53         DATA_BLOB out_security_buffer;
  54         NTSTATUS status;
  55
  56         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
  57
  58         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
  59                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  60         }
  61
  62         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  63
  64         body_size = SVAL(inbody, 0x00);
  65         if (body_size != expected_body_size) {
  66                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  67         }
  68
  69         in_security_offset = SVAL(inbody, 0x0C);
  70         in_security_length = SVAL(inbody, 0x0E);
  71
  72         if (in_security_offset != (SMB2_HDR_BODY + (body_size & 0xFFFFFFFE))) {
  73                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  74         }
  75
  76         if (in_security_length > req->in.vector[i+2].iov_len) {
  77                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  78         }
  79
  80         in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
  81         in_security_mode = CVAL(inbody, 0x03);
  82         in_security_buffer.data = (uint8_t *)req->in.vector[i+2].iov_base;
  83         in_security_buffer.length = in_security_length;
  84
  85         status = smbd_smb2_session_setup(req,
  86                                          in_session_id,
  87                                          in_security_mode,
  88                                          in_security_buffer,
  89                                          &out_session_flags,
  90                                          &out_security_buffer,
  91                                          &out_session_id);
  92         if (!NT_STATUS_IS_OK(status) &&
  93             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  94                 status = nt_status_squash(status);
  95                 return smbd_smb2_request_error(req, status);
  96         }
  97
  98         out_security_offset = SMB2_HDR_BODY + 0x08;
  99
 100         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 101
 102         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 103         if (outbody.data == NULL) {
 104                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 105         }
 106
 107         SBVAL(outhdr, SMB2_HDR_SESSION_ID, out_session_id);
 108
 109         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 110         SSVAL(outbody.data, 0x02,
 111               out_session_flags);               /* session flags */
 112         SSVAL(outbody.data, 0x04,
 113               out_security_offset);             /* security buffer offset */
 114         SSVAL(outbody.data, 0x06,
 115               out_security_buffer.length);      /* security buffer length */
 116
 117         outdyn = out_security_buffer;
 118
 119         return smbd_smb2_request_done_ex(req, status, outbody, &outdyn,
 120                                          __location__);
 121 }
 122
 123 static int smbd_smb2_session_destructor(struct smbd_smb2_session *session)
 124 {
 125         if (session->sconn == NULL) {
 126                 return 0;
 127         }
 128
 129         /* first free all tcons */
 130         while (session->tcons.list) {
 131                 talloc_free(session->tcons.list);
 132         }
 133
 134         idr_remove(session->sconn->smb2.sessions.idtree, session->vuid);
 135         DLIST_REMOVE(session->sconn->smb2.sessions.list, session);
 136         invalidate_vuid(session->sconn, session->vuid);
 137
 138         session->vuid = 0;
 139         session->status = NT_STATUS_USER_SESSION_DELETED;
 140         session->sconn = NULL;
 141
 142         return 0;
 143 }
 144
 145 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *req,
 146                                         uint64_t in_session_id,
 147                                         uint8_t in_security_mode,
 148                                         DATA_BLOB in_security_buffer,
 149                                         uint16_t *out_session_flags,
 150                                         DATA_BLOB *out_security_buffer,
 151                                         uint64_t *out_session_id)
 152 {
 153         struct smbd_smb2_session *session;
 154         NTSTATUS status;
 155
 156         *out_session_flags = 0;
 157         *out_session_id = 0;
 158
 159         if (in_session_id == 0) {
 160                 int id;
 161
 162                 /* create a new session */
 163                 session = talloc_zero(req->sconn, struct smbd_smb2_session);
 164                 if (session == NULL) {
 165                         return NT_STATUS_NO_MEMORY;
 166                 }
 167                 session->status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 168                 id = idr_get_new_random(req->sconn->smb2.sessions.idtree,
 169                                         session,
 170                                         req->sconn->smb2.sessions.limit);
 171                 if (id == -1) {
 172                         return NT_STATUS_INSUFFICIENT_RESOURCES;
 173                 }
 174                 session->vuid = id;
 175
 176                 session->tcons.idtree = idr_init(session);
 177                 if (session->tcons.idtree == NULL) {
 178                         return NT_STATUS_NO_MEMORY;
 179                 }
 180                 session->tcons.limit = 0x0000FFFE;
 181                 session->tcons.list = NULL;
 182
 183                 DLIST_ADD_END(req->sconn->smb2.sessions.list, session,
 184                               struct smbd_smb2_session *);
 185                 session->sconn = req->sconn;
 186                 talloc_set_destructor(session, smbd_smb2_session_destructor);
 187         } else {
 188                 void *p;
 189
 190                 /* lookup an existing session */
 191                 p = idr_find(req->sconn->smb2.sessions.idtree, in_session_id);
 192                 if (p == NULL) {
 193                         return NT_STATUS_USER_SESSION_DELETED;
 194                 }
 195                 session = talloc_get_type_abort(p, struct smbd_smb2_session);
 196         }
 197
 198         if (NT_STATUS_IS_OK(session->status)) {
 199                 return NT_STATUS_REQUEST_NOT_ACCEPTED;
 200         }
 201
 202         if (session->auth_ntlmssp_state == NULL) {
 203                 status = auth_ntlmssp_start(&session->auth_ntlmssp_state);
 204                 if (!NT_STATUS_IS_OK(status)) {
 205                         TALLOC_FREE(session);
 206                         return status;
 207                 }
 208         }
 209
 210         if (in_security_buffer.data[0] == ASN1_APPLICATION(0)) {
 211                 DATA_BLOB secblob_in;
 212                 DATA_BLOB chal_out;
 213                 char *kerb_mech = NULL;
 214
 215                 status = parse_spnego_mechanisms(in_security_buffer,
 216                                 &secblob_in, &kerb_mech);
 217                 if (!NT_STATUS_IS_OK(status)) {
 218                         TALLOC_FREE(session);
 219                         return nt_status_squash(status);
 220                 }
 221
 222                 /* For now, just SPNEGO NTLMSSP - krb5 goes here later.. */
 223                 status = auth_ntlmssp_update(session->auth_ntlmssp_state,
 224                                              secblob_in,
 225                                              &chal_out);
 226
 227                 if (!NT_STATUS_IS_OK(status) &&
 228                                 !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 229                         auth_ntlmssp_end(&session->auth_ntlmssp_state);
 230                         TALLOC_FREE(session);
 231                         return nt_status_squash(status);
 232                 }
 233
 234                 *out_security_buffer = spnego_gen_auth_response(&chal_out,
 235                                 status, OID_NTLMSSP);
 236
 237                 *out_session_id = session->vuid;
 238                 return status;
 239         } else if (in_security_buffer.data[0] == ASN1_CONTEXT(1)) {
 240                 DATA_BLOB auth = data_blob_null;
 241                 DATA_BLOB auth_out = data_blob_null;
 242
 243                 /* its an auth packet */
 244                 if (!spnego_parse_auth(in_security_buffer, &auth)) {
 245                         TALLOC_FREE(session);
 246                         return NT_STATUS_LOGON_FAILURE;
 247                 }
 248                 /* For now, just SPNEGO NTLMSSP - krb5 goes here later.. */
 249                 status = auth_ntlmssp_update(session->auth_ntlmssp_state,
 250                                              auth,
 251                                              &auth_out);
 252                 if (!NT_STATUS_IS_OK(status)) {
 253                         auth_ntlmssp_end(&session->auth_ntlmssp_state);
 254                         TALLOC_FREE(session);
 255                         return nt_status_squash(status);
 256                 }
 257
 258                 *out_security_buffer = spnego_gen_auth_response(&auth_out,
 259                                 status, NULL);
 260
 261                 *out_session_id = session->vuid;
 262         } else if (strncmp((char *)(in_security_buffer.data), "NTLMSSP", 7) == 0) {
 263
 264                 /* RAW NTLMSSP */
 265                 status = auth_ntlmssp_update(session->auth_ntlmssp_state,
 266                                              in_security_buffer,
 267                                              out_security_buffer);
 268
 269                 if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 270                         *out_session_id = session->vuid;
 271                         return status;
 272                 }
 273                 if (!NT_STATUS_IS_OK(status)) {
 274                         auth_ntlmssp_end(&session->auth_ntlmssp_state);
 275                         TALLOC_FREE(session);
 276                         return nt_status_squash(status);
 277                 }
 278                 *out_session_id = session->vuid;
 279         }
 280
 281         /* TODO: setup session key for signing */
 282
 283         if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
 284             lp_server_signing() == Required) {
 285                 session->do_signing = true;
 286         }
 287
 288         if (session->auth_ntlmssp_state->server_info->guest) {
 289                 /* we map anonymous to guest internally */
 290                 *out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
 291                 *out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
 292                 /* force no signing */
 293                 session->do_signing = false;
 294         }
 295
 296         session->server_info = session->auth_ntlmssp_state->server_info;
 297         data_blob_free(&session->server_info->user_session_key);
 298         session->server_info->user_session_key =
 299                         data_blob_talloc(
 300                         session->server_info,
 301                         session->auth_ntlmssp_state->ntlmssp_state->session_key.data,
 302                         session->auth_ntlmssp_state->ntlmssp_state->session_key.length);
 303         if (session->auth_ntlmssp_state->ntlmssp_state->session_key.length > 0) {
 304                 if (session->server_info->user_session_key.data == NULL) {
 305                         TALLOC_FREE(session);
 306                         return NT_STATUS_NO_MEMORY;
 307                 }
 308         }
 309         session->session_key = session->server_info->user_session_key;
 310
 311         session->compat_vuser = talloc_zero(session, user_struct);
 312         if (session->compat_vuser == NULL) {
 313                 TALLOC_FREE(session);
 314                 return NT_STATUS_NO_MEMORY;
 315         }
 316         session->compat_vuser->auth_ntlmssp_state = session->auth_ntlmssp_state;
 317         session->compat_vuser->homes_snum = -1;
 318         session->compat_vuser->server_info = session->server_info;
 319         session->compat_vuser->session_keystr = NULL;
 320         session->compat_vuser->vuid = session->vuid;
 321         DLIST_ADD(session->sconn->smb1.sessions.validated_users, session->compat_vuser);
 322
 323         session->status = NT_STATUS_OK;
 324
 325         /*
 326          * we attach the session to the request
 327          * so that the response can be signed
 328          */
 329         req->session = session;
 330         if (session->do_signing) {
 331                 req->do_signing = true;
 332         }
 333
 334         *out_session_id = session->vuid;
 335         return status;
 336 }
 337
 338 NTSTATUS smbd_smb2_request_check_session(struct smbd_smb2_request *req)
 339 {
 340         const uint8_t *inhdr;
 341         int i = req->current_idx;
 342         uint64_t in_session_id;
 343         void *p;
 344         struct smbd_smb2_session *session;
 345
 346         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
 347
 348         in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
 349
 350         /* lookup an existing session */
 351         p = idr_find(req->sconn->smb2.sessions.idtree, in_session_id);
 352         if (p == NULL) {
 353                 return NT_STATUS_USER_SESSION_DELETED;
 354         }
 355         session = talloc_get_type_abort(p, struct smbd_smb2_session);
 356
 357         if (!NT_STATUS_IS_OK(session->status)) {
 358                 return NT_STATUS_ACCESS_DENIED;
 359         }
 360
 361         set_current_user_info(session->server_info->sanitized_username,
 362                               session->server_info->unix_name,
 363                               pdb_get_domain(session->server_info->sam_account));
 364
 365         req->session = session;
 366         return NT_STATUS_OK;
 367 }
 368
 369 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
 370 {
 371         const uint8_t *inbody;
 372         int i = req->current_idx;
 373         DATA_BLOB outbody;
 374         size_t expected_body_size = 0x04;
 375         size_t body_size;
 376
 377         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
 378                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 379         }
 380
 381         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
 382
 383         body_size = SVAL(inbody, 0x00);
 384         if (body_size != expected_body_size) {
 385                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 386         }
 387
 388         /*
 389          * TODO: cancel all outstanding requests on the session
 390          *       and delete all tree connections.
 391          */
 392         smbd_smb2_session_destructor(req->session);
 393         /*
 394          * we may need to sign the response, so we need to keep
 395          * the session until the response is sent to the wire.
 396          */
 397         talloc_steal(req, req->session);
 398
 399         outbody = data_blob_talloc(req->out.vector, NULL, 0x04);
 400         if (outbody.data == NULL) {
 401                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 402         }
 403
 404         SSVAL(outbody.data, 0x00, 0x04);        /* struct size */
 405         SSVAL(outbody.data, 0x02, 0);           /* reserved */
 406
 407         return smbd_smb2_request_done(req, outbody, NULL);
 408 }