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