source4/rpc_server/dcesrv_auth.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    server side dcerpc authentication code
   5
   6    Copyright (C) Andrew Tridgell 2003
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24
  25
  26 /*
  27   parse any auth information from a dcerpc bind request
  28   return False if we can't handle the auth request for some
  29   reason (in which case we send a bind_nak)
  30 */
  31 BOOL dcesrv_auth_bind(struct dcesrv_call_state *call)
  32 {
  33         struct dcerpc_packet *pkt = &call->pkt;
  34         struct dcesrv_connection *dce_conn = call->conn;
  35         NTSTATUS status;
  36
  37         if (pkt->u.bind.auth_info.length == 0) {
  38                 dce_conn->auth_state.auth_info = NULL;
  39                 return True;
  40         }
  41
  42         dce_conn->auth_state.auth_info = talloc_p(dce_conn->mem_ctx, struct dcerpc_auth);
  43         if (!dce_conn->auth_state.auth_info) {
  44                 return False;
  45         }
  46
  47         status = ndr_pull_struct_blob(&pkt->u.bind.auth_info,
  48                                       call->mem_ctx,
  49                                       dce_conn->auth_state.auth_info,
  50                                       (ndr_pull_flags_fn_t)ndr_pull_dcerpc_auth);
  51         if (!NT_STATUS_IS_OK(status)) {
  52                 return False;
  53         }
  54
  55         if (dce_conn->auth_state.auth_info->auth_type != DCERPC_AUTH_TYPE_NTLMSSP) {
  56                 /* only do NTLMSSP for now */
  57                 DEBUG(2,("auth_type %d not supported\n", dce_conn->auth_state.auth_info->auth_type));
  58                 return False;
  59         }
  60
  61         if (dce_conn->auth_state.auth_info->auth_level != DCERPC_AUTH_LEVEL_INTEGRITY &&
  62             dce_conn->auth_state.auth_info->auth_level != DCERPC_AUTH_LEVEL_PRIVACY) {
  63                 DEBUG(2,("auth_level %d not supported\n", dce_conn->auth_state.auth_info->auth_level));
  64                 return False;
  65         }
  66
  67         status = auth_ntlmssp_start(&dce_conn->auth_state.ntlmssp_state);
  68         if (!NT_STATUS_IS_OK(status)) {
  69                 DEBUG(2, ("Failed to start NTLMSSP subsystem!\n"));
  70                 return False;
  71         }
  72
  73         return True;
  74 }
  75
  76 /*
  77   add any auth information needed in a bind ack
  78 */
  79 BOOL dcesrv_auth_bind_ack(struct dcesrv_call_state *call, struct dcerpc_packet *pkt)
  80 {
  81         struct dcesrv_connection *dce_conn = call->conn;
  82         NTSTATUS status;
  83
  84         if (!call->conn->auth_state.ntlmssp_state) {
  85                 return True;
  86         }
  87
  88         status = auth_ntlmssp_update(dce_conn->auth_state.ntlmssp_state,
  89                                      call->mem_ctx,
  90                                      dce_conn->auth_state.auth_info->credentials,
  91                                      &dce_conn->auth_state.auth_info->credentials);
  92         if (!NT_STATUS_IS_OK(status) &&
  93             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  94                 DEBUG(2, ("Failed to start NTLMSSP process NTLMSSP negotiate: %s\n", nt_errstr(status)));
  95                 return False;
  96         }
  97
  98         dce_conn->auth_state.auth_info->auth_pad_length = 0;
  99         dce_conn->auth_state.auth_info->auth_reserved = 0;
 100
 101         return True;
 102 }
 103
 104
 105 /*
 106   process the final stage of a NTLMSSP auth request
 107 */
 108 BOOL dcesrv_auth_auth3(struct dcesrv_call_state *call)
 109 {
 110         struct dcerpc_packet *pkt = &call->pkt;
 111         struct dcesrv_connection *dce_conn = call->conn;
 112         NTSTATUS status;
 113
 114         if (!dce_conn->auth_state.auth_info ||
 115             !dce_conn->auth_state.ntlmssp_state ||
 116             pkt->u.auth.auth_info.length == 0) {
 117                 return False;
 118         }
 119
 120         status = ndr_pull_struct_blob(&pkt->u.auth.auth_info,
 121                                       call->mem_ctx,
 122                                       dce_conn->auth_state.auth_info,
 123                                       (ndr_pull_flags_fn_t)ndr_pull_dcerpc_auth);
 124         if (!NT_STATUS_IS_OK(status)) {
 125                 return False;
 126         }
 127
 128         if (dce_conn->auth_state.auth_info->auth_type != DCERPC_AUTH_TYPE_NTLMSSP) {
 129                 return False;
 130         }
 131         if (dce_conn->auth_state.auth_info->auth_level != DCERPC_AUTH_LEVEL_INTEGRITY &&
 132             dce_conn->auth_state.auth_info->auth_level != DCERPC_AUTH_LEVEL_PRIVACY) {
 133                 return False;
 134         }
 135
 136         status = auth_ntlmssp_update(dce_conn->auth_state.ntlmssp_state,
 137                                      call->mem_ctx,
 138                                      dce_conn->auth_state.auth_info->credentials,
 139                                      &dce_conn->auth_state.auth_info->credentials);
 140         if (!NT_STATUS_IS_OK(status)) {
 141                 DEBUG(4, ("User failed to authenticated with NTLMSSP: %s\n", nt_errstr(status)));
 142                 return False;
 143         }
 144
 145         return True;
 146 }
 147
 148
 149 /*
 150   check credentials on a request
 151 */
 152 BOOL dcesrv_auth_request(struct dcesrv_call_state *call)
 153 {
 154         struct dcerpc_packet *pkt = &call->pkt;
 155         struct dcesrv_connection *dce_conn = call->conn;
 156         DATA_BLOB auth_blob;
 157         struct dcerpc_auth auth;
 158         struct ndr_pull *ndr;
 159         NTSTATUS status;
 160
 161         if (!dce_conn->auth_state.auth_info ||
 162             !dce_conn->auth_state.ntlmssp_state) {
 163                 return True;
 164         }
 165
 166         auth_blob.length = 8 + pkt->auth_length;
 167
 168         /* check for a valid length */
 169         if (pkt->u.request.stub_and_verifier.length < auth_blob.length) {
 170                 return False;
 171         }
 172
 173         auth_blob.data =
 174                 pkt->u.request.stub_and_verifier.data +
 175                 pkt->u.request.stub_and_verifier.length - auth_blob.length;
 176         pkt->u.request.stub_and_verifier.length -= auth_blob.length;
 177
 178         /* pull the auth structure */
 179         ndr = ndr_pull_init_blob(&auth_blob, call->mem_ctx);
 180         if (!ndr) {
 181                 return False;
 182         }
 183
 184         if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
 185                 ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
 186         }
 187
 188         status = ndr_pull_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, &auth);
 189         if (!NT_STATUS_IS_OK(status)) {
 190                 return False;
 191         }
 192
 193         /* check signature or unseal the packet */
 194         switch (dce_conn->auth_state.auth_info->auth_level) {
 195         case DCERPC_AUTH_LEVEL_PRIVACY:
 196                 status = ntlmssp_unseal_packet(dce_conn->auth_state.ntlmssp_state->ntlmssp_state,
 197                                                call->mem_ctx,
 198                                                pkt->u.request.stub_and_verifier.data,
 199                                                pkt->u.request.stub_and_verifier.length,
 200                                                &auth.credentials);
 201                 break;
 202
 203         case DCERPC_AUTH_LEVEL_INTEGRITY:
 204                 status = ntlmssp_check_packet(dce_conn->auth_state.ntlmssp_state->ntlmssp_state,
 205                                               call->mem_ctx,
 206                                               pkt->u.request.stub_and_verifier.data,
 207                                               pkt->u.request.stub_and_verifier.length,
 208                                               &auth.credentials);
 209                 break;
 210
 211         default:
 212                 status = NT_STATUS_INVALID_LEVEL;
 213                 break;
 214         }
 215
 216         /* remove the indicated amount of paddiing */
 217         if (pkt->u.request.stub_and_verifier.length < auth.auth_pad_length) {
 218                 return False;
 219         }
 220         pkt->u.request.stub_and_verifier.length -= auth.auth_pad_length;
 221
 222         return NT_STATUS_IS_OK(status);
 223 }
 224
 225
 226 /*
 227    push a signed or sealed dcerpc request packet into a blob
 228 */
 229 BOOL dcesrv_auth_response(struct dcesrv_call_state *call,
 230                           DATA_BLOB *blob, struct dcerpc_packet *pkt)
 231 {
 232         struct dcesrv_connection *dce_conn = call->conn;
 233         NTSTATUS status;
 234         struct ndr_push *ndr;
 235
 236         /* non-signed packets are simple */
 237         if (!dce_conn->auth_state.auth_info || !dce_conn->auth_state.ntlmssp_state) {
 238                 status = dcerpc_push_auth(blob, call->mem_ctx, pkt, NULL);
 239                 return NT_STATUS_IS_OK(status);
 240         }
 241
 242         ndr = ndr_push_init_ctx(call->mem_ctx);
 243         if (!ndr) {
 244                 return False;
 245         }
 246
 247         if (pkt->drep[0] & DCERPC_DREP_LE) {
 248                 ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
 249         }
 250
 251         status = ndr_push_dcerpc_packet(ndr, NDR_SCALARS|NDR_BUFFERS, pkt);
 252         if (!NT_STATUS_IS_OK(status)) {
 253                 return False;
 254         }
 255
 256         /* pad to 8 byte multiple */
 257         dce_conn->auth_state.auth_info->auth_pad_length = NDR_ALIGN(ndr, 8);
 258         ndr_push_zero(ndr, dce_conn->auth_state.auth_info->auth_pad_length);
 259
 260         /* sign or seal the packet */
 261         switch (dce_conn->auth_state.auth_info->auth_level) {
 262         case DCERPC_AUTH_LEVEL_PRIVACY:
 263                 status = ntlmssp_seal_packet(dce_conn->auth_state.ntlmssp_state->ntlmssp_state,
 264                                              call->mem_ctx,
 265                                              ndr->data + DCERPC_REQUEST_LENGTH,
 266                                              ndr->offset - DCERPC_REQUEST_LENGTH,
 267                                              &dce_conn->auth_state.auth_info->credentials);
 268                 break;
 269
 270         case DCERPC_AUTH_LEVEL_INTEGRITY:
 271                 status = ntlmssp_sign_packet(dce_conn->auth_state.ntlmssp_state->ntlmssp_state,
 272                                              call->mem_ctx,
 273                                              ndr->data + DCERPC_REQUEST_LENGTH,
 274                                              ndr->offset - DCERPC_REQUEST_LENGTH,
 275                                              &dce_conn->auth_state.auth_info->credentials);
 276                 break;
 277         default:
 278                 status = NT_STATUS_INVALID_LEVEL;
 279                 break;
 280         }
 281
 282         if (!NT_STATUS_IS_OK(status)) {
 283                 return False;
 284         }
 285
 286         /* add the auth verifier */
 287         status = ndr_push_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, dce_conn->auth_state.auth_info);
 288         if (!NT_STATUS_IS_OK(status)) {
 289                 return False;
 290         }
 291
 292         /* extract the whole packet as a blob */
 293         *blob = ndr_push_blob(ndr);
 294
 295         /* fill in the fragment length and auth_length, we can't fill
 296            in these earlier as we don't know the signature length (it
 297            could be variable length) */
 298         dcerpc_set_frag_length(blob, blob->length);
 299         dcerpc_set_auth_length(blob, dce_conn->auth_state.auth_info->credentials.length);
 300
 301         data_blob_free(&dce_conn->auth_state.auth_info->credentials);
 302
 303         return True;
 304 }