source3/winbindd/winbindd_dual_ndr.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Provide parent->child communication based on NDR marshalling
   5
   6    Copyright (C) Volker Lendecke 2009
   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 3 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, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 /*
  23  * This file implements an RPC between winbind parent and child processes,
  24  * leveraging the autogenerated marshalling routines for MSRPC. This is not
  25  * MSRPC, as it does not go through the whole DCERPC fragmentation, we just
  26  * leverage much the same infrastructure we already have for it.
  27  */
  28
  29 #include "includes.h"
  30 #include "winbindd/winbindd.h"
  31 #include "winbindd/winbindd_proto.h"
  32 #include "librpc/gen_ndr/srv_wbint.h"
  33
  34 struct wb_ndr_transport_priv {
  35         struct winbindd_child *child;
  36 };
  37
  38 struct wb_ndr_dispatch_state {
  39         const struct ndr_interface_call *call;
  40         void *r;
  41         struct ndr_push *push;
  42         struct winbindd_request request;
  43         struct winbindd_response *response;
  44 };
  45
  46 static void wb_ndr_dispatch_done(struct tevent_req *subreq);
  47
  48 static struct tevent_req *wb_ndr_dispatch_send(TALLOC_CTX *mem_ctx,
  49                                                struct tevent_context *ev,
  50                                                struct rpc_pipe_client *cli,
  51                                                const struct ndr_interface_table *table,
  52                                                uint32_t opnum,
  53                                                void *r)
  54 {
  55         struct tevent_req *req, *subreq;
  56         struct wb_ndr_dispatch_state *state;
  57         struct wb_ndr_transport_priv *transport = talloc_get_type_abort(
  58                 cli->transport->priv, struct wb_ndr_transport_priv);
  59         DATA_BLOB blob;
  60         enum ndr_err_code ndr_err;
  61
  62         req = tevent_req_create(mem_ctx, &state,
  63                                 struct wb_ndr_dispatch_state);
  64         if (req == NULL) {
  65                 return NULL;
  66         }
  67
  68         state->r = r;
  69         state->call = &table->calls[opnum];
  70
  71         state->push = ndr_push_init_ctx(state, NULL);
  72         if (tevent_req_nomem(state->push, req)) {
  73                 return tevent_req_post(req, ev);
  74         }
  75
  76         ndr_err = state->call->ndr_push(state->push, NDR_IN, r);
  77         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  78                 tevent_req_nterror(req, ndr_map_error2ntstatus(ndr_err));
  79                 TALLOC_FREE(state->push);
  80                 return tevent_req_post(req, ev);
  81         }
  82
  83         blob = ndr_push_blob(state->push);
  84
  85         state->request.cmd = WINBINDD_DUAL_NDRCMD;
  86         state->request.data.ndrcmd = opnum;
  87         state->request.extra_data.data = (char *)blob.data;
  88         state->request.extra_len = blob.length;
  89
  90         subreq = wb_child_request_send(state, ev, transport->child,
  91                                        &state->request);
  92         if (tevent_req_nomem(subreq, req)) {
  93                 return tevent_req_post(req, ev);
  94         }
  95         tevent_req_set_callback(subreq, wb_ndr_dispatch_done, req);
  96         return req;
  97 }
  98
  99 static void wb_ndr_dispatch_done(struct tevent_req *subreq)
 100 {
 101         struct tevent_req *req = tevent_req_callback_data(
 102                 subreq, struct tevent_req);
 103         struct wb_ndr_dispatch_state *state = tevent_req_data(
 104                 req, struct wb_ndr_dispatch_state);
 105         int ret, err;
 106
 107         ret = wb_child_request_recv(subreq, state, &state->response, &err);
 108         TALLOC_FREE(subreq);
 109         if (ret == -1) {
 110                 tevent_req_nterror(req, map_nt_error_from_unix(err));
 111                 return;
 112         }
 113         tevent_req_done(req);
 114 }
 115
 116 static NTSTATUS wb_ndr_dispatch_recv(struct tevent_req *req,
 117                                      TALLOC_CTX *mem_ctx)
 118 {
 119         struct wb_ndr_dispatch_state *state = tevent_req_data(
 120                 req, struct wb_ndr_dispatch_state);
 121         NTSTATUS status;
 122         struct ndr_pull *pull;
 123         enum ndr_err_code ndr_err;
 124         DATA_BLOB blob;
 125
 126         if (tevent_req_is_nterror(req, &status)) {
 127                 return status;
 128         }
 129
 130         blob.data = (uint8_t *)state->response->extra_data.data;
 131         blob.length = state->response->length
 132                 - sizeof(struct winbindd_response);
 133
 134         pull = ndr_pull_init_blob(&blob, mem_ctx, NULL);
 135         if (pull == NULL) {
 136                 return NT_STATUS_NO_MEMORY;
 137         }
 138
 139         /* have the ndr parser alloc memory for us */
 140         pull->flags |= LIBNDR_FLAG_REF_ALLOC;
 141         ndr_err = state->call->ndr_pull(pull, NDR_OUT, state->r);
 142         TALLOC_FREE(pull);
 143
 144         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 145                 return ndr_map_error2ntstatus(ndr_err);
 146         }
 147
 148         return NT_STATUS_OK;
 149 }
 150
 151 static NTSTATUS wb_ndr_dispatch(struct rpc_pipe_client *cli,
 152                                 TALLOC_CTX *mem_ctx,
 153                                 const struct ndr_interface_table *table,
 154                                 uint32_t opnum, void *r)
 155 {
 156         TALLOC_CTX *frame = talloc_stackframe();
 157         struct event_context *ev;
 158         struct tevent_req *req;
 159         NTSTATUS status = NT_STATUS_OK;
 160
 161         ev = event_context_init(frame);
 162         if (ev == NULL) {
 163                 status = NT_STATUS_NO_MEMORY;
 164                 goto fail;
 165         }
 166
 167         req = wb_ndr_dispatch_send(frame, ev, cli, table, opnum, r);
 168         if (req == NULL) {
 169                 status = NT_STATUS_NO_MEMORY;
 170                 goto fail;
 171         }
 172
 173         if (!tevent_req_poll(req, ev)) {
 174                 status = map_nt_error_from_unix(errno);
 175                 goto fail;
 176         }
 177
 178         status = wb_ndr_dispatch_recv(req, mem_ctx);
 179  fail:
 180         TALLOC_FREE(frame);
 181         return status;
 182 }
 183
 184 struct rpc_pipe_client *wbint_rpccli_create(TALLOC_CTX *mem_ctx,
 185                                             struct winbindd_child *child)
 186 {
 187         struct rpc_pipe_client *result;
 188         struct wb_ndr_transport_priv *transp;
 189
 190         result = talloc(mem_ctx, struct rpc_pipe_client);
 191         if (result == NULL) {
 192                 return NULL;
 193         }
 194         result->abstract_syntax = ndr_table_wbint.syntax_id;
 195         result->transfer_syntax = ndr_transfer_syntax;
 196         result->dispatch = wb_ndr_dispatch;
 197         result->dispatch_send = wb_ndr_dispatch_send;
 198         result->dispatch_recv = wb_ndr_dispatch_recv;
 199         result->max_xmit_frag = RPC_MAX_PDU_FRAG_LEN;
 200         result->max_recv_frag = RPC_MAX_PDU_FRAG_LEN;
 201         result->desthost = NULL;
 202         result->srv_name_slash = NULL;
 203
 204         /*
 205          * Initialize a fake transport. Due to our own wb_ndr_dispatch
 206          * function we don't use all the fragmentation engine in
 207          * cli_pipe, which would use all the _read and _write
 208          * functions in rpc_cli_transport. But we need a place to
 209          * store the child struct in, and we're re-using
 210          * result->transport->priv for that.
 211          */
 212
 213         result->transport = talloc_zero(result, struct rpc_cli_transport);
 214         if (result->transport == NULL) {
 215                 TALLOC_FREE(result);
 216                 return NULL;
 217         }
 218         transp = talloc(result->transport, struct wb_ndr_transport_priv);
 219         if (transp == NULL) {
 220                 TALLOC_FREE(result);
 221                 return NULL;
 222         }
 223         transp->child = child;
 224         result->transport->priv = transp;
 225         return result;
 226 }
 227
 228 enum winbindd_result winbindd_dual_ndrcmd(struct winbindd_domain *domain,
 229                                           struct winbindd_cli_state *state)
 230 {
 231         pipes_struct p;
 232         struct api_struct *fns;
 233         int num_fns;
 234         bool ret;
 235
 236         wbint_get_pipe_fns(&fns, &num_fns);
 237
 238         if (state->request->data.ndrcmd >= num_fns) {
 239                 return WINBINDD_ERROR;
 240         }
 241
 242         ZERO_STRUCT(p);
 243         p.mem_ctx = talloc_stackframe();
 244         p.in_data.data.buffer_size = state->request->extra_len;
 245         p.in_data.data.data_p = state->request->extra_data.data;
 246         prs_init(&p.out_data.rdata, 0, state->mem_ctx, false);
 247
 248         ret = fns[state->request->data.ndrcmd].fn(&p);
 249         TALLOC_FREE(p.mem_ctx);
 250         if (!ret) {
 251                 return WINBINDD_ERROR;
 252         }
 253
 254         state->response->extra_data.data =
 255                 talloc_memdup(state->mem_ctx, p.out_data.rdata.data_p,
 256                               p.out_data.rdata.data_offset);
 257         state->response->length += p.out_data.rdata.data_offset;
 258         prs_mem_free(&p.out_data.rdata);
 259         if (state->response->extra_data.data == NULL) {
 260                 return WINBINDD_ERROR;
 261         }
 262         return WINBINDD_OK;
 263 }
 264
 265 /*
 266  * Just a dummy to make srv_wbint.c happy
 267  */
 268 NTSTATUS rpc_srv_register(int version, const char *clnt, const char *srv,
 269                           const struct ndr_interface_table *iface,
 270                           const struct api_struct *cmds, int size)
 271 {
 272         return NT_STATUS_OK;
 273 }