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