Line data    Source code

       1             : /*
       2             :    Unix SMB/CIFS implementation.
       3             : 
       4             :    server side dcerpc common code
       5             : 
       6             :    Copyright (C) Andrew Tridgell 2003-2010
       7             :    Copyright (C) Stefan (metze) Metzmacher 2004-2005
       8             : 
       9             :    This program is free software; you can redistribute it and/or modify
      10             :    it under the terms of the GNU General Public License as published by
      11             :    the Free Software Foundation; either version 3 of the License, or
      12             :    (at your option) any later version.
      13             : 
      14             :    This program is distributed in the hope that it will be useful,
      15             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      16             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      17             :    GNU General Public License for more details.
      18             : 
      19             :    You should have received a copy of the GNU General Public License
      20             :    along with this program.  If not, see <http://www.gnu.org/licenses/>.
      21             : */
      22             : 
      23             : #include "includes.h"
      24             : #include "librpc/rpc/dcesrv_core.h"
      25             : #include "librpc/rpc/dcesrv_core_proto.h"
      26             : #include "librpc/rpc/dcerpc_util.h"
      27             : #include "auth/gensec/gensec.h"
      28             : #include "lib/util/dlinklist.h"
      29             : #include "param/param.h"
      30             : 
      31             : /*
      32             :   move a call from an existing linked list to the specified list. This
      33             :   prevents bugs where we forget to remove the call from a previous
      34             :   list when moving it.
      35             :  */
      36      829224 : static void dcesrv_call_set_list(struct dcesrv_call_state *call,
      37             :                                  enum dcesrv_call_list list)
      38             : {
      39      829224 :         switch (call->list) {
      40        2438 :         case DCESRV_LIST_NONE:
      41        2438 :                 break;
      42           0 :         case DCESRV_LIST_CALL_LIST:
      43           0 :                 DLIST_REMOVE(call->conn->call_list, call);
      44           0 :                 break;
      45          46 :         case DCESRV_LIST_FRAGMENTED_CALL_LIST:
      46          46 :                 DLIST_REMOVE(call->conn->incoming_fragmented_call_list, call);
      47          46 :                 break;
      48      826394 :         case DCESRV_LIST_PENDING_CALL_LIST:
      49      826394 :                 DLIST_REMOVE(call->conn->pending_call_list, call);
      50      819298 :                 break;
      51             :         }
      52      829224 :         call->list = list;
      53      829224 :         switch (list) {
      54           0 :         case DCESRV_LIST_NONE:
      55           0 :                 break;
      56      829224 :         case DCESRV_LIST_CALL_LIST:
      57      829224 :                 DLIST_ADD_END(call->conn->call_list, call);
      58      821782 :                 break;
      59           0 :         case DCESRV_LIST_FRAGMENTED_CALL_LIST:
      60           0 :                 DLIST_ADD_END(call->conn->incoming_fragmented_call_list, call);
      61           0 :                 break;
      62           0 :         case DCESRV_LIST_PENDING_CALL_LIST:
      63           0 :                 DLIST_ADD_END(call->conn->pending_call_list, call);
      64           0 :                 break;
      65             :         }
      66      829224 : }
      67             : 
      68             : 
      69     1182154 : void dcesrv_init_hdr(struct ncacn_packet *pkt, bool bigendian)
      70             : {
      71     1182154 :         pkt->rpc_vers = 5;
      72     1182154 :         pkt->rpc_vers_minor = 0;
      73     1182154 :         if (bigendian) {
      74           0 :                 pkt->drep[0] = 0;
      75             :         } else {
      76     1182154 :                 pkt->drep[0] = DCERPC_DREP_LE;
      77             :         }
      78     1182154 :         pkt->drep[1] = 0;
      79     1182154 :         pkt->drep[2] = 0;
      80     1182154 :         pkt->drep[3] = 0;
      81     1182154 : }
      82             : 
      83             : 
      84             : /*
      85             :   return a dcerpc fault
      86             : */
      87        2846 : NTSTATUS dcesrv_fault_with_flags(struct dcesrv_call_state *call,
      88             :                                  uint32_t fault_code,
      89             :                                  uint8_t extra_flags)
      90             : {
      91         346 :         struct ncacn_packet pkt;
      92         346 :         struct data_blob_list_item *rep;
      93         346 :         NTSTATUS status;
      94             : 
      95             :         /* setup a fault */
      96        2846 :         dcesrv_init_hdr(&pkt, lpcfg_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
      97        2846 :         pkt.auth_length = 0;
      98        2846 :         pkt.call_id = call->pkt.call_id;
      99        2846 :         pkt.ptype = DCERPC_PKT_FAULT;
     100        2846 :         pkt.pfc_flags = DCERPC_PFC_FLAG_FIRST | DCERPC_PFC_FLAG_LAST | extra_flags;
     101        2846 :         pkt.u.fault.alloc_hint = 24;
     102        2846 :         if (call->context != NULL) {
     103        2704 :                 pkt.u.fault.context_id = call->context->context_id;
     104             :         } else {
     105         142 :                 pkt.u.fault.context_id = 0;
     106             :         }
     107        2846 :         pkt.u.fault.cancel_count = 0;
     108        2846 :         pkt.u.fault.flags = 0;
     109        2846 :         pkt.u.fault.status = fault_code;
     110        2846 :         pkt.u.fault.reserved = 0;
     111        2846 :         pkt.u.fault.error_and_verifier = data_blob_null;
     112             : 
     113        2846 :         rep = talloc_zero(call, struct data_blob_list_item);
     114        2846 :         if (!rep) {
     115           0 :                 return NT_STATUS_NO_MEMORY;
     116             :         }
     117             : 
     118        2846 :         status = dcerpc_ncacn_push_auth(&rep->blob, call, &pkt, NULL);
     119        2846 :         if (!NT_STATUS_IS_OK(status)) {
     120           0 :                 return status;
     121             :         }
     122             : 
     123        2846 :         dcerpc_set_frag_length(&rep->blob, rep->blob.length);
     124             : 
     125        2846 :         DLIST_ADD_END(call->replies, rep);
     126        2846 :         dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);
     127             : 
     128        2846 :         if (call->conn->call_list && call->conn->call_list->replies) {
     129        2846 :                 if (call->conn->transport.report_output_data) {
     130        2846 :                         call->conn->transport.report_output_data(call->conn);
     131             :                 }
     132             :         }
     133             : 
     134        2846 :         return NT_STATUS_OK;
     135             : }
     136             : 
     137        2504 : NTSTATUS dcesrv_fault(struct dcesrv_call_state *call, uint32_t fault_code)
     138             : {
     139        2504 :         return dcesrv_fault_with_flags(call, fault_code, 0);
     140             : }
     141             : 
     142      826394 : _PUBLIC_ NTSTATUS dcesrv_reply(struct dcesrv_call_state *call)
     143             : {
     144        7096 :         struct ndr_push *push;
     145        7096 :         NTSTATUS status;
     146        7096 :         DATA_BLOB stub;
     147        7096 :         uint32_t total_length, chunk_size;
     148      826394 :         struct dcesrv_connection_context *context = call->context;
     149      826394 :         struct dcesrv_auth *auth = call->auth_state;
     150      826394 :         size_t sig_size = 0;
     151             : 
     152             :         /* call the reply function */
     153      826394 :         status = context->iface->reply(call, call, call->r);
     154      826394 :         if (!NT_STATUS_IS_OK(status)) {
     155          16 :                 return dcesrv_fault(call, call->fault_code);
     156             :         }
     157             : 
     158             :         /* form the reply NDR */
     159      826378 :         push = ndr_push_init_ctx(call);
     160      826378 :         NT_STATUS_HAVE_NO_MEMORY(push);
     161             : 
     162             :         /* carry over the pointer count to the reply in case we are
     163             :            using full pointer. See NDR specification for full
     164             :            pointers */
     165      826378 :         push->ptr_count = call->ndr_pull->ptr_count;
     166             : 
     167      826378 :         if (lpcfg_rpc_big_endian(call->conn->dce_ctx->lp_ctx)) {
     168           0 :                 push->flags |= LIBNDR_FLAG_BIGENDIAN;
     169             :         }
     170             : 
     171      826378 :         if (context->ndr64) {
     172           0 :                 push->flags |= LIBNDR_FLAG_NDR64;
     173             :         }
     174             : 
     175      826378 :         status = context->iface->ndr_push(call, call, push, call->r);
     176      826378 :         if (!NT_STATUS_IS_OK(status)) {
     177           0 :                 return dcesrv_fault(call, call->fault_code);
     178             :         }
     179             : 
     180      826378 :         stub = ndr_push_blob(push);
     181             : 
     182      826378 :         dcesrv_save_ndr_fuzz_seed(stub,
     183             :                                   call,
     184             :                                   NDR_OUT);
     185             : 
     186      826378 :         total_length = stub.length;
     187             : 
     188             :         /* we can write a full max_recv_frag size, minus the dcerpc
     189             :            request header size */
     190      826378 :         chunk_size = call->conn->max_xmit_frag;
     191      826378 :         chunk_size -= DCERPC_REQUEST_LENGTH;
     192      826378 :         if (auth->auth_finished && auth->gensec_security != NULL) {
     193       96057 :                 size_t max_payload = chunk_size;
     194             : 
     195       96057 :                 max_payload -= DCERPC_AUTH_TRAILER_LENGTH;
     196       96057 :                 max_payload -= (max_payload % DCERPC_AUTH_PAD_ALIGNMENT);
     197             : 
     198       96057 :                 sig_size = gensec_sig_size(auth->gensec_security,
     199             :                                            max_payload);
     200       96057 :                 if (sig_size) {
     201       94677 :                         chunk_size -= DCERPC_AUTH_TRAILER_LENGTH;
     202       94677 :                         chunk_size -= sig_size;
     203             :                 }
     204             :         }
     205      826378 :         chunk_size -= (chunk_size % DCERPC_AUTH_PAD_ALIGNMENT);
     206             : 
     207        7178 :         do {
     208        7178 :                 uint32_t length;
     209        7178 :                 struct data_blob_list_item *rep;
     210        7178 :                 struct ncacn_packet pkt;
     211        7178 :                 bool ok;
     212             : 
     213     1117713 :                 rep = talloc_zero(call, struct data_blob_list_item);
     214     1117713 :                 NT_STATUS_HAVE_NO_MEMORY(rep);
     215             : 
     216     1117713 :                 length = MIN(chunk_size, stub.length);
     217             : 
     218             :                 /* form the dcerpc response packet */
     219     1117713 :                 dcesrv_init_hdr(&pkt,
     220     1117713 :                                 lpcfg_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
     221     1117713 :                 pkt.auth_length = 0;
     222     1117713 :                 pkt.call_id = call->pkt.call_id;
     223     1117713 :                 pkt.ptype = DCERPC_PKT_RESPONSE;
     224     1117713 :                 pkt.pfc_flags = 0;
     225     1117713 :                 if (stub.length == total_length) {
     226      826378 :                         pkt.pfc_flags |= DCERPC_PFC_FLAG_FIRST;
     227             :                 }
     228     1117713 :                 if (length == stub.length) {
     229      826378 :                         pkt.pfc_flags |= DCERPC_PFC_FLAG_LAST;
     230             :                 }
     231     1117713 :                 pkt.u.response.alloc_hint = stub.length;
     232             :                 /*
     233             :                  * bug for bug, feature for feature...
     234             :                  *
     235             :                  * Windows truncates the context_id with & 0xFF,
     236             :                  * so we do.
     237             :                  */
     238     1117713 :                 pkt.u.response.context_id = context->context_id & 0xFF;
     239     1117713 :                 pkt.u.response.cancel_count = 0;
     240     1117713 :                 pkt.u.response.stub_and_verifier.data = stub.data;
     241     1117713 :                 pkt.u.response.stub_and_verifier.length = length;
     242             : 
     243     1117713 :                 ok = dcesrv_auth_pkt_push(call, &rep->blob, sig_size,
     244             :                                           DCERPC_RESPONSE_LENGTH,
     245             :                                           &pkt.u.response.stub_and_verifier,
     246             :                                           &pkt);
     247     1117713 :                 if (!ok) {
     248           0 :                         return dcesrv_fault(call, DCERPC_FAULT_OTHER);
     249             :                 }
     250             : 
     251     1117713 :                 dcerpc_set_frag_length(&rep->blob, rep->blob.length);
     252             : 
     253     1117713 :                 DLIST_ADD_END(call->replies, rep);
     254             : 
     255     1117713 :                 stub.data += length;
     256     1117713 :                 stub.length -= length;
     257     1117713 :         } while (stub.length != 0);
     258             : 
     259             :         /* move the call from the pending to the finished calls list */
     260      826378 :         dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);
     261             : 
     262      826378 :         if (call->conn->call_list && call->conn->call_list->replies) {
     263      826378 :                 if (call->conn->transport.report_output_data) {
     264      826378 :                         call->conn->transport.report_output_data(call->conn);
     265             :                 }
     266             :         }
     267             : 
     268      826378 :         return NT_STATUS_OK;
     269             : }
     270             : 
     271       17805 : _PUBLIC_ void _dcesrv_async_reply(struct dcesrv_call_state *call,
     272             :                                   const char *func,
     273             :                                   const char *location)
     274             : {
     275       17805 :         struct dcesrv_connection *conn = call->conn;
     276        1290 :         NTSTATUS status;
     277             : 
     278       17805 :         status = dcesrv_reply(call);
     279       17805 :         if (!NT_STATUS_IS_OK(status)) {
     280           0 :                 D_ERR("%s: %s: dcesrv_async_reply() failed - %s\n",
     281             :                       func, location, nt_errstr(status));
     282           0 :                 dcesrv_terminate_connection(conn, nt_errstr(status));
     283             :         }
     284       17805 : }