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 "../source4/libcli/smb2/smb2_constants.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 }
 119
 120 static int smbd_smb2_session_destructor(struct smbd_smb2_session *session)
 121 {
 122         if (session->conn == NULL) {
 123                 return 0;
 124         }
 125
 126         /* first free all tcons */
 127         while (session->tcons.list) {
 128                 talloc_free(session->tcons.list);
 129         }
 130
 131         idr_remove(session->conn->smb2.sessions.idtree, session->vuid);
 132         DLIST_REMOVE(session->conn->smb2.sessions.list, session);
 133
 134         session->vuid = 0;
 135         session->status = NT_STATUS_USER_SESSION_DELETED;
 136         session->conn = NULL;
 137
 138         return 0;
 139 }
 140
 141 static NTSTATUS smbd_smb2_session_setup(struct smbd_smb2_request *req,
 142                                         uint64_t in_session_id,
 143                                         uint8_t in_security_mode,
 144                                         DATA_BLOB in_security_buffer,
 145                                         uint16_t *out_session_flags,
 146                                         DATA_BLOB *out_security_buffer,
 147                                         uint64_t *out_session_id)
 148 {
 149         struct smbd_smb2_session *session;
 150         NTSTATUS status;
 151
 152         *out_session_flags = 0;
 153         *out_session_id = 0;
 154
 155         if (in_session_id == 0) {
 156                 int id;
 157
 158                 /* create a new session */
 159                 session = talloc_zero(req->conn, struct smbd_smb2_session);
 160                 if (session == NULL) {
 161                         return NT_STATUS_NO_MEMORY;
 162                 }
 163                 session->status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 164                 id = idr_get_new_random(req->conn->smb2.sessions.idtree,
 165                                         session,
 166                                         req->conn->smb2.sessions.limit);
 167                 if (id == -1) {
 168                         return NT_STATUS_INSUFFICIENT_RESOURCES;
 169                 }
 170                 session->vuid = id;
 171
 172                 session->tcons.idtree = idr_init(session);
 173                 if (session->tcons.idtree == NULL) {
 174                         return NT_STATUS_NO_MEMORY;
 175                 }
 176                 session->tcons.limit = 0x0000FFFE;
 177                 session->tcons.list = NULL;
 178
 179                 DLIST_ADD_END(req->conn->smb2.sessions.list, session,
 180                               struct smbd_smb2_session *);
 181                 session->conn = req->conn;
 182                 talloc_set_destructor(session, smbd_smb2_session_destructor);
 183         } else {
 184                 void *p;
 185
 186                 /* lookup an existing session */
 187                 p = idr_find(req->conn->smb2.sessions.idtree, in_session_id);
 188                 if (p == NULL) {
 189                         return NT_STATUS_USER_SESSION_DELETED;
 190                 }
 191                 session = talloc_get_type_abort(p, struct smbd_smb2_session);
 192         }
 193
 194         if (NT_STATUS_IS_OK(session->status)) {
 195                 return NT_STATUS_REQUEST_NOT_ACCEPTED;
 196         }
 197
 198         if (session->auth_ntlmssp_state == NULL) {
 199                 status = auth_ntlmssp_start(&session->auth_ntlmssp_state);
 200                 if (!NT_STATUS_IS_OK(status)) {
 201                         TALLOC_FREE(session);
 202                         return status;
 203                 }
 204         }
 205
 206         if (in_security_buffer.data[0] == ASN1_APPLICATION(0)) {
 207                 DATA_BLOB secblob_in;
 208                 DATA_BLOB chal_out;
 209                 char *kerb_mech = NULL;
 210
 211                 status = parse_spnego_mechanisms(in_security_buffer,
 212                                 &secblob_in, &kerb_mech);
 213                 if (!NT_STATUS_IS_OK(status)) {
 214                         TALLOC_FREE(session);
 215                         return nt_status_squash(status);
 216                 }
 217
 218                 /* For now, just SPNEGO NTLMSSP - krb5 goes here later.. */
 219                 status = auth_ntlmssp_update(session->auth_ntlmssp_state,
 220                                              secblob_in,
 221                                              &chal_out);
 222
 223                 if (!NT_STATUS_IS_OK(status) &&
 224                                 !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 225                         auth_ntlmssp_end(&session->auth_ntlmssp_state);
 226                         TALLOC_FREE(session);
 227                         return nt_status_squash(status);
 228                 }
 229
 230                 *out_security_buffer = spnego_gen_auth_response(&chal_out,
 231                                 status, OID_NTLMSSP);
 232
 233                 *out_session_id = session->vuid;
 234                 return status;
 235         } else if (in_security_buffer.data[0] == ASN1_CONTEXT(1)) {
 236                 DATA_BLOB auth = data_blob_null;
 237                 DATA_BLOB auth_out = data_blob_null;
 238
 239                 /* its an auth packet */
 240                 if (!spnego_parse_auth(in_security_buffer, &auth)) {
 241                         TALLOC_FREE(session);
 242                         return NT_STATUS_LOGON_FAILURE;
 243                 }
 244                 /* For now, just SPNEGO NTLMSSP - krb5 goes here later.. */
 245                 status = auth_ntlmssp_update(session->auth_ntlmssp_state,
 246                                              auth,
 247                                              &auth_out);
 248                 if (!NT_STATUS_IS_OK(status)) {
 249                         auth_ntlmssp_end(&session->auth_ntlmssp_state);
 250                         TALLOC_FREE(session);
 251                         return nt_status_squash(status);
 252                 }
 253
 254                 *out_security_buffer = spnego_gen_auth_response(&auth_out,
 255                                 status, NULL);
 256
 257                 *out_session_id = session->vuid;
 258         } else if (strncmp((char *)(in_security_buffer.data), "NTLMSSP", 7) == 0) {
 259
 260                 /* RAW NTLMSSP */
 261                 status = auth_ntlmssp_update(session->auth_ntlmssp_state,
 262                                              in_security_buffer,
 263                                              out_security_buffer);
 264
 265                 if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 266                         *out_session_id = session->vuid;
 267                         return status;
 268                 }
 269                 if (!NT_STATUS_IS_OK(status)) {
 270                         auth_ntlmssp_end(&session->auth_ntlmssp_state);
 271                         TALLOC_FREE(session);
 272                         return nt_status_squash(status);
 273                 }
 274                 *out_session_id = session->vuid;
 275         }
 276
 277         /* TODO: setup session key for signing */
 278
 279         if ((in_security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) ||
 280             lp_server_signing() == Required) {
 281                 session->do_signing = true;
 282         }
 283
 284         if (session->auth_ntlmssp_state->server_info->guest) {
 285                 /* we map anonymous to guest internally */
 286                 *out_session_flags |= SMB2_SESSION_FLAG_IS_GUEST;
 287                 *out_session_flags |= SMB2_SESSION_FLAG_IS_NULL;
 288                 /* force no signing */
 289                 session->do_signing = false;
 290         }
 291
 292         session->server_info = session->auth_ntlmssp_state->server_info;
 293         data_blob_free(&session->server_info->user_session_key);
 294         session->server_info->user_session_key =
 295                         data_blob_talloc(
 296                         session->server_info,
 297                         session->auth_ntlmssp_state->ntlmssp_state->session_key.data,
 298                         session->auth_ntlmssp_state->ntlmssp_state->session_key.length);
 299         if (session->auth_ntlmssp_state->ntlmssp_state->session_key.length > 0) {
 300                 if (session->server_info->user_session_key.data == NULL) {
 301                         TALLOC_FREE(session);
 302                         return NT_STATUS_NO_MEMORY;
 303                 }
 304         }
 305         session->session_key = session->server_info->user_session_key;
 306
 307         session->compat_vuser = talloc_zero(session, user_struct);
 308         if (session->compat_vuser == NULL) {
 309                 TALLOC_FREE(session);
 310                 return NT_STATUS_NO_MEMORY;
 311         }
 312         session->compat_vuser->auth_ntlmssp_state = session->auth_ntlmssp_state;
 313         session->compat_vuser->homes_snum = -1;
 314         session->compat_vuser->server_info = session->server_info;
 315         session->compat_vuser->session_keystr = NULL;
 316         session->compat_vuser->vuid = session->vuid;
 317         DLIST_ADD(session->conn->smb1.sessions.validated_users, session->compat_vuser);
 318
 319         session->status = NT_STATUS_OK;
 320
 321         /*
 322          * we attach the session to the request
 323          * so that the response can be signed
 324          */
 325         req->session = session;
 326         if (session->do_signing) {
 327                 req->do_signing = true;
 328         }
 329
 330         *out_session_id = session->vuid;
 331         return status;
 332 }
 333
 334 NTSTATUS smbd_smb2_request_check_session(struct smbd_smb2_request *req)
 335 {
 336         const uint8_t *inhdr;
 337         int i = req->current_idx;
 338         uint64_t in_session_id;
 339         void *p;
 340         struct smbd_smb2_session *session;
 341
 342         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
 343
 344         in_session_id = BVAL(inhdr, SMB2_HDR_SESSION_ID);
 345
 346         /* lookup an existing session */
 347         p = idr_find(req->conn->smb2.sessions.idtree, in_session_id);
 348         if (p == NULL) {
 349                 return NT_STATUS_USER_SESSION_DELETED;
 350         }
 351         session = talloc_get_type_abort(p, struct smbd_smb2_session);
 352
 353         if (!NT_STATUS_IS_OK(session->status)) {
 354                 return NT_STATUS_ACCESS_DENIED;
 355         }
 356
 357         set_current_user_info(session->server_info->sanitized_username,
 358                               session->server_info->unix_name,
 359                               pdb_get_domain(session->server_info->sam_account));
 360
 361         req->session = session;
 362         return NT_STATUS_OK;
 363 }
 364
 365 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req)
 366 {
 367         const uint8_t *inbody;
 368         int i = req->current_idx;
 369         DATA_BLOB outbody;
 370         size_t expected_body_size = 0x04;
 371         size_t body_size;
 372
 373         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
 374                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 375         }
 376
 377         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
 378
 379         body_size = SVAL(inbody, 0x00);
 380         if (body_size != expected_body_size) {
 381                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 382         }
 383
 384         /*
 385          * TODO: cancel all outstanding requests on the session
 386          *       and delete all tree connections.
 387          */
 388         smbd_smb2_session_destructor(req->session);
 389         /*
 390          * we may need to sign the response, so we need to keep
 391          * the session until the response is sent to the wire.
 392          */
 393         talloc_steal(req, req->session);
 394
 395         outbody = data_blob_talloc(req->out.vector, NULL, 0x04);
 396         if (outbody.data == NULL) {
 397                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 398         }
 399
 400         SSVAL(outbody.data, 0x00, 0x04);        /* struct size */
 401         SSVAL(outbody.data, 0x02, 0);           /* reserved */
 402
 403         return smbd_smb2_request_done(req, outbody, NULL);
 404 }