source4/smb_server/smb2/sesssetup.c

   1 /*
   2    Unix SMB2 implementation.
   3
   4    Copyright (C) Andrew Bartlett        2001-2005
   5    Copyright (C) Stefan Metzmacher      2005
   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 <tevent.h>
  23 #include "auth/gensec/gensec.h"
  24 #include "auth/auth.h"
  25 #include "libcli/smb2/smb2.h"
  26 #include "libcli/smb2/smb2_calls.h"
  27 #include "smb_server/smb_server.h"
  28 #include "smb_server/smb2/smb2_server.h"
  29 #include "smbd/service_stream.h"
  30 #include "lib/stream/packet.h"
  31
  32 static void smb2srv_sesssetup_send(struct smb2srv_request *req, union smb_sesssetup *io)
  33 {
  34         uint16_t credit;
  35
  36         if (NT_STATUS_IS_OK(req->status)) {
  37                 credit = 0x0003;
  38         } else if (NT_STATUS_EQUAL(req->status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  39                 credit = 0x0002;
  40         } else {
  41                 smb2srv_send_error(req, req->status);
  42                 return;
  43         }
  44
  45         SMB2SRV_CHECK(smb2srv_setup_reply(req, 0x08, true, io->smb2.out.secblob.length));
  46
  47         SSVAL(req->out.hdr, SMB2_HDR_CREDIT,    credit);
  48         SBVAL(req->out.hdr, SMB2_HDR_SESSION_ID,        io->smb2.out.uid);
  49
  50         SSVAL(req->out.body, 0x02, io->smb2.out.session_flags);
  51         SMB2SRV_CHECK(smb2_push_o16s16_blob(&req->out, 0x04, io->smb2.out.secblob));
  52
  53         smb2srv_send_reply(req);
  54 }
  55
  56 struct smb2srv_sesssetup_callback_ctx {
  57         struct smb2srv_request *req;
  58         union smb_sesssetup *io;
  59         struct smbsrv_session *smb_sess;
  60 };
  61
  62 static void smb2srv_sesssetup_callback(struct tevent_req *subreq)
  63 {
  64         struct smb2srv_sesssetup_callback_ctx *ctx = tevent_req_callback_data(subreq,
  65                                                      struct smb2srv_sesssetup_callback_ctx);
  66         struct smb2srv_request *req = ctx->req;
  67         union smb_sesssetup *io = ctx->io;
  68         struct smbsrv_session *smb_sess = ctx->smb_sess;
  69         struct auth_session_info *session_info = NULL;
  70         NTSTATUS status;
  71
  72         packet_recv_enable(req->smb_conn->packet);
  73
  74         status = gensec_update_recv(subreq, req, &io->smb2.out.secblob);
  75         TALLOC_FREE(subreq);
  76         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  77                 goto done;
  78         } else if (!NT_STATUS_IS_OK(status)) {
  79                 goto failed;
  80         }
  81
  82         status = gensec_session_info(smb_sess->gensec_ctx, &session_info);
  83         if (!NT_STATUS_IS_OK(status)) {
  84                 goto failed;
  85         }
  86
  87         /* Ensure this is marked as a 'real' vuid, not one
  88          * simply valid for the session setup leg */
  89         status = smbsrv_session_sesssetup_finished(smb_sess, session_info);
  90         if (!NT_STATUS_IS_OK(status)) {
  91                 goto failed;
  92         }
  93         req->session = smb_sess;
  94
  95         if (smb_sess->smb2_signing.required) {
  96                 /* activate smb2 signing on the session */
  97                 smb_sess->smb2_signing.active = true;
  98         }
  99 done:
 100         io->smb2.out.uid = smb_sess->vuid;
 101 failed:
 102         req->status = nt_status_squash(status);
 103         smb2srv_sesssetup_send(req, io);
 104         if (!NT_STATUS_IS_OK(status) && !
 105             NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 106                 talloc_free(smb_sess);
 107         }
 108 }
 109
 110 static void smb2srv_sesssetup_backend(struct smb2srv_request *req, union smb_sesssetup *io)
 111 {
 112         NTSTATUS status;
 113         struct smb2srv_sesssetup_callback_ctx *callback_ctx;
 114         struct smbsrv_session *smb_sess = NULL;
 115         uint64_t vuid;
 116         struct tevent_req *subreq;
 117
 118         io->smb2.out.session_flags = 0;
 119         io->smb2.out.uid        = 0;
 120         io->smb2.out.secblob = data_blob(NULL, 0);
 121
 122         vuid = BVAL(req->in.hdr, SMB2_HDR_SESSION_ID);
 123
 124         /*
 125          * only when we got '0' we should allocate a new session
 126          */
 127         if (vuid == 0) {
 128                 struct gensec_security *gensec_ctx;
 129
 130                 status = samba_server_gensec_start(req,
 131                                                    req->smb_conn->connection->event.ctx,
 132                                                    req->smb_conn->connection->msg_ctx,
 133                                                    req->smb_conn->lp_ctx,
 134                                                    req->smb_conn->negotiate.server_credentials,
 135                                                    "cifs",
 136                                                    &gensec_ctx);
 137                 if (!NT_STATUS_IS_OK(status)) {
 138                         DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
 139                         goto failed;
 140                 }
 141
 142                 gensec_want_feature(gensec_ctx, GENSEC_FEATURE_SESSION_KEY);
 143
 144                 status = gensec_start_mech_by_oid(gensec_ctx, GENSEC_OID_SPNEGO);
 145                 if (!NT_STATUS_IS_OK(status)) {
 146                         DEBUG(1, ("Failed to start GENSEC SPNEGO server code: %s\n", nt_errstr(status)));
 147                         goto failed;
 148                 }
 149
 150                 /* allocate a new session */
 151                 smb_sess = smbsrv_session_new(req->smb_conn, req->smb_conn, gensec_ctx);
 152                 if (!smb_sess) {
 153                         status = NT_STATUS_INSUFFICIENT_RESOURCES;
 154                         goto failed;
 155                 }
 156                 status = smbsrv_smb2_init_tcons(smb_sess);
 157                 if (!NT_STATUS_IS_OK(status)) {
 158                         goto failed;
 159                 }
 160         } else {
 161                 /* lookup an existing session */
 162                 smb_sess = smbsrv_session_find_sesssetup(req->smb_conn, vuid);
 163         }
 164
 165         if (!smb_sess) {
 166                 /* see WSPP test suite - test 11 */
 167                 status = NT_STATUS_REQUEST_NOT_ACCEPTED;
 168                 goto failed;
 169         }
 170
 171         if (!smb_sess->gensec_ctx) {
 172                 status = NT_STATUS_INTERNAL_ERROR;
 173                 DEBUG(1, ("Internal ERROR: no gensec_ctx on session: %s\n", nt_errstr(status)));
 174                 goto failed;
 175         }
 176
 177         callback_ctx = talloc(req, struct smb2srv_sesssetup_callback_ctx);
 178         if (!callback_ctx) goto nomem;
 179         callback_ctx->req       = req;
 180         callback_ctx->io        = io;
 181         callback_ctx->smb_sess  = smb_sess;
 182
 183         subreq = gensec_update_send(callback_ctx,
 184                                     req->smb_conn->connection->event.ctx,
 185                                     smb_sess->gensec_ctx,
 186                                     io->smb2.in.secblob);
 187         if (!subreq) goto nomem;
 188         tevent_req_set_callback(subreq, smb2srv_sesssetup_callback, callback_ctx);
 189
 190         /* note that we ignore SMB2_NEGOTIATE_SIGNING_ENABLED from the client.
 191            This is deliberate as windows does not set it even when it does
 192            set SMB2_NEGOTIATE_SIGNING_REQUIRED */
 193         if (io->smb2.in.security_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) {
 194                 smb_sess->smb2_signing.required = true;
 195         } else if (req->smb_conn->smb2_signing_required) {
 196                 /*
 197                  * if required signing was negotiates in SMB2 Negotiate
 198                  * then the client made an error not using it here
 199                  */
 200                 DEBUG(1, ("SMB2 signing required on the connection but not used on session\n"));
 201                 req->status = NT_STATUS_FOOBAR;
 202                 goto failed;
 203         }
 204
 205         /* disable receipt of more packets on this socket until we've
 206            finished with the session setup. This avoids a problem with
 207            crashes if we get EOF on the socket while processing a session
 208            setup */
 209         packet_recv_disable(req->smb_conn->packet);
 210
 211         return;
 212 nomem:
 213         status = NT_STATUS_NO_MEMORY;
 214 failed:
 215         talloc_free(smb_sess);
 216         req->status = nt_status_squash(status);
 217         smb2srv_sesssetup_send(req, io);
 218 }
 219
 220 void smb2srv_sesssetup_recv(struct smb2srv_request *req)
 221 {
 222         union smb_sesssetup *io;
 223
 224         SMB2SRV_CHECK_BODY_SIZE(req, 0x18, true);
 225         SMB2SRV_TALLOC_IO_PTR(io, union smb_sesssetup);
 226
 227         io->smb2.level                 = RAW_SESSSETUP_SMB2;
 228         io->smb2.in.vc_number          = CVAL(req->in.body, 0x02);
 229         io->smb2.in.security_mode      = CVAL(req->in.body, 0x03);
 230         io->smb2.in.capabilities       = IVAL(req->in.body, 0x04);
 231         io->smb2.in.channel            = IVAL(req->in.body, 0x08);
 232         io->smb2.in.previous_sessionid = BVAL(req->in.body, 0x10);
 233         SMB2SRV_CHECK(smb2_pull_o16s16_blob(&req->in, io, req->in.body+0x0C, &io->smb2.in.secblob));
 234
 235         smb2srv_sesssetup_backend(req, io);
 236 }
 237
 238 static int smb2srv_cleanup_session_destructor(struct smbsrv_session **session)
 239 {
 240         /* TODO: call ntvfs backends to close file of this session */
 241         DEBUG(0,("free session[%p]\n", *session));
 242         talloc_free(*session);
 243         return 0;
 244 }
 245
 246 static NTSTATUS smb2srv_logoff_backend(struct smb2srv_request *req)
 247 {
 248         struct smbsrv_session **session_ptr;
 249
 250         /* we need to destroy the session after sending the reply */
 251         session_ptr = talloc(req, struct smbsrv_session *);
 252         NT_STATUS_HAVE_NO_MEMORY(session_ptr);
 253
 254         *session_ptr = req->session;
 255         talloc_set_destructor(session_ptr, smb2srv_cleanup_session_destructor);
 256
 257         return NT_STATUS_OK;
 258 }
 259
 260 static void smb2srv_logoff_send(struct smb2srv_request *req)
 261 {
 262         if (NT_STATUS_IS_ERR(req->status)) {
 263                 smb2srv_send_error(req, req->status);
 264                 return;
 265         }
 266
 267         SMB2SRV_CHECK(smb2srv_setup_reply(req, 0x04, false, 0));
 268
 269         SSVAL(req->out.body, 0x02, 0);
 270
 271         smb2srv_send_reply(req);
 272 }
 273
 274 void smb2srv_logoff_recv(struct smb2srv_request *req)
 275 {
 276         uint16_t _pad;
 277
 278         SMB2SRV_CHECK_BODY_SIZE(req, 0x04, false);
 279
 280         _pad    = SVAL(req->in.body, 0x02);
 281
 282         req->status = smb2srv_logoff_backend(req);
 283
 284         if (req->control_flags & SMB2SRV_REQ_CTRL_FLAG_NOT_REPLY) {
 285                 talloc_free(req);
 286                 return;
 287         }
 288         smb2srv_logoff_send(req);
 289 }