source4/samba/service_named_pipe.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    helper functions for NAMED PIPE servers
   5
   6    Copyright (C) Stefan (metze) Metzmacher      2008
   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 #include "includes.h"
  23 #include <tevent.h>
  24 #include "samba/service.h"
  25 #include "param/param.h"
  26 #include "auth/auth.h"
  27 #include "auth/session.h"
  28 #include "auth/auth_sam_reply.h"
  29 #include "lib/socket/socket.h"
  30 #include "lib/tsocket/tsocket.h"
  31 #include "libcli/util/tstream.h"
  32 #include "librpc/gen_ndr/ndr_named_pipe_auth.h"
  33 #include "system/passwd.h"
  34 #include "system/network.h"
  35 #include "libcli/raw/smb.h"
  36 #include "auth/session.h"
  37 #include "libcli/security/security.h"
  38 #include "libcli/named_pipe_auth/npa_tstream.h"
  39
  40 struct named_pipe_socket {
  41         const char *pipe_name;
  42         const char *pipe_path;
  43         const struct stream_server_ops *ops;
  44         void *private_data;
  45 };
  46
  47 static void named_pipe_accept_done(struct tevent_req *subreq);
  48
  49 static void named_pipe_accept(struct stream_connection *conn)
  50 {
  51         struct tstream_context *plain_tstream;
  52         int fd;
  53         struct tevent_req *subreq;
  54         int ret;
  55
  56         /* Let tstream take over fd operations */
  57
  58         fd = socket_get_fd(conn->socket);
  59         socket_set_flags(conn->socket, SOCKET_FLAG_NOCLOSE);
  60         TALLOC_FREE(conn->event.fde);
  61         TALLOC_FREE(conn->socket);
  62
  63         ret = tstream_bsd_existing_socket(conn, fd, &plain_tstream);
  64         if (ret != 0) {
  65                 stream_terminate_connection(conn,
  66                                 "named_pipe_accept: out of memory");
  67                 return;
  68         }
  69
  70         subreq = tstream_npa_accept_existing_send(conn, conn->event.ctx,
  71                                                   plain_tstream,
  72                                                   FILE_TYPE_MESSAGE_MODE_PIPE,
  73                                                   0xff | 0x0400 | 0x0100,
  74                                                   4096);
  75         if (subreq == NULL) {
  76                 stream_terminate_connection(conn,
  77                         "named_pipe_accept: "
  78                         "no memory for tstream_npa_accept_existing_send");
  79                 return;
  80         }
  81         tevent_req_set_callback(subreq, named_pipe_accept_done, conn);
  82 }
  83
  84 static void named_pipe_accept_done(struct tevent_req *subreq)
  85 {
  86         struct stream_connection *conn = tevent_req_callback_data(subreq,
  87                                                 struct stream_connection);
  88         struct named_pipe_socket *pipe_sock =
  89                                 talloc_get_type(conn->private_data,
  90                                                 struct named_pipe_socket);
  91         enum dcerpc_transport_t transport;
  92         struct tsocket_address *remote_client_addr;
  93         char *remote_client_name;
  94         struct tsocket_address *local_server_addr;
  95         char *local_server_name;
  96         struct auth_session_info_transport *session_info_transport;
  97         const char *reason = NULL;
  98         TALLOC_CTX *tmp_ctx;
  99         int error;
 100         int ret;
 101
 102         tmp_ctx = talloc_new(conn);
 103         if (!tmp_ctx) {
 104                 reason = "Out of memory!\n";
 105                 goto out;
 106         }
 107
 108         ret = tstream_npa_accept_existing_recv(subreq, &error, tmp_ctx,
 109                                                &conn->tstream,
 110                                                NULL,
 111                                                &transport,
 112                                                &remote_client_addr,
 113                                                &remote_client_name,
 114                                                &local_server_addr,
 115                                                &local_server_name,
 116                                                &session_info_transport);
 117         TALLOC_FREE(subreq);
 118         if (ret != 0) {
 119                 reason = talloc_asprintf(conn,
 120                                          "tstream_npa_accept_existing_recv()"
 121                                          " failed: %s", strerror(error));
 122                 goto out;
 123         }
 124
 125         conn->local_address = talloc_move(conn, &local_server_addr);
 126         conn->remote_address = talloc_move(conn, &remote_client_addr);
 127
 128         DBG_DEBUG("Accepted npa connection from %s. "
 129                   "Client: %s (%s). Server: %s (%s)\n",
 130                   tsocket_address_string(conn->remote_address, tmp_ctx),
 131                   local_server_name,
 132                   tsocket_address_string(local_server_addr, tmp_ctx),
 133                   remote_client_name,
 134                   tsocket_address_string(remote_client_addr, tmp_ctx));
 135
 136         conn->session_info = auth_session_info_from_transport(conn, session_info_transport,
 137                                                               conn->lp_ctx,
 138                                                               &reason);
 139         if (!conn->session_info) {
 140                 goto out;
 141         }
 142
 143         if (transport == NCACN_NP) {
 144                 if (security_token_is_system(conn->session_info->security_token)) {
 145                         reason = talloc_asprintf(
 146                                 conn,
 147                                 "System token not allowed on transport %d\n",
 148                                 transport);
 149                         goto out;
 150                 }
 151         } else if (transport == NCALRPC) {
 152                 /*
 153                  * TODO:
 154                  * we should somehow remember the given transport on
 155                  * the connection, but that's a task for another day
 156                  * as it's not trivial to do...
 157                  */
 158         } else {
 159                 reason = talloc_asprintf(
 160                         conn,
 161                         "Only allow NCACN_NP or NCALRPC transport on named pipes, "
 162                         "got %d\n",
 163                         (int)transport);
 164                 goto out;
 165         }
 166
 167         /*
 168          * hand over to the real pipe implementation,
 169          * now that we have setup the transport session_info
 170          */
 171         conn->ops = pipe_sock->ops;
 172         conn->private_data = pipe_sock->private_data;
 173         conn->ops->accept_connection(conn);
 174
 175         DBG_DEBUG("named pipe connection [%s] established\n", conn->ops->name);
 176
 177         talloc_free(tmp_ctx);
 178         return;
 179
 180 out:
 181         talloc_free(tmp_ctx);
 182         if (!reason) {
 183                 reason = "Internal error";
 184         }
 185         stream_terminate_connection(conn, reason);
 186 }
 187
 188 /*
 189   called when a pipe socket becomes readable
 190 */
 191 static void named_pipe_recv(struct stream_connection *conn, uint16_t flags)
 192 {
 193         stream_terminate_connection(conn, "named_pipe_recv: called");
 194 }
 195
 196 /*
 197   called when a pipe socket becomes writable
 198 */
 199 static void named_pipe_send(struct stream_connection *conn, uint16_t flags)
 200 {
 201         stream_terminate_connection(conn, "named_pipe_send: called");
 202 }
 203
 204 static const struct stream_server_ops named_pipe_stream_ops = {
 205         .name                   = "named_pipe",
 206         .accept_connection      = named_pipe_accept,
 207         .recv_handler           = named_pipe_recv,
 208         .send_handler           = named_pipe_send,
 209 };
 210
 211 NTSTATUS tstream_setup_named_pipe(TALLOC_CTX *mem_ctx,
 212                                   struct tevent_context *event_context,
 213                                   struct loadparm_context *lp_ctx,
 214                                   const struct model_ops *model_ops,
 215                                   const struct stream_server_ops *stream_ops,
 216                                   const char *pipe_name,
 217                                   void *private_data,
 218                                   void *process_context)
 219 {
 220         char *dirname;
 221         struct named_pipe_socket *pipe_sock;
 222         NTSTATUS status = NT_STATUS_NO_MEMORY;;
 223
 224         pipe_sock = talloc(mem_ctx, struct named_pipe_socket);
 225         if (pipe_sock == NULL) {
 226                 goto fail;
 227         }
 228
 229         /* remember the details about the pipe */
 230         pipe_sock->pipe_name    = strlower_talloc(pipe_sock, pipe_name);
 231         if (pipe_sock->pipe_name == NULL) {
 232                 goto fail;
 233         }
 234
 235         if (!directory_create_or_exist(lpcfg_ncalrpc_dir(lp_ctx), 0755)) {
 236                 status = map_nt_error_from_unix_common(errno);
 237                 DBG_ERR("Failed to create ncalrpc pipe directory '%s' - %s\n",
 238                         lpcfg_ncalrpc_dir(lp_ctx), nt_errstr(status));
 239                 goto fail;
 240         }
 241
 242         dirname = talloc_asprintf(pipe_sock, "%s/np", lpcfg_ncalrpc_dir(lp_ctx));
 243         if (dirname == NULL) {
 244                 goto fail;
 245         }
 246
 247         if (!directory_create_or_exist_strict(dirname, geteuid(), 0700)) {
 248                 status = map_nt_error_from_unix_common(errno);
 249                 DBG_ERR("Failed to create stream pipe directory '%s' - %s\n",
 250                         dirname, nt_errstr(status));
 251                 goto fail;
 252         }
 253
 254         if (strncmp(pipe_name, "\\pipe\\", 6) == 0) {
 255                 pipe_name += 6;
 256         }
 257
 258         pipe_sock->pipe_path = talloc_asprintf(pipe_sock, "%s/%s", dirname,
 259                                                pipe_name);
 260         if (pipe_sock->pipe_path == NULL) {
 261                 goto fail;
 262         }
 263
 264         talloc_free(dirname);
 265
 266         pipe_sock->ops = stream_ops;
 267         pipe_sock->private_data = private_data;
 268
 269         status = stream_setup_socket(pipe_sock,
 270                                      event_context,
 271                                      lp_ctx,
 272                                      model_ops,
 273                                      &named_pipe_stream_ops,
 274                                      "unix",
 275                                      pipe_sock->pipe_path,
 276                                      NULL,
 277                                      NULL,
 278                                      pipe_sock,
 279                                      process_context);
 280         if (!NT_STATUS_IS_OK(status)) {
 281                 goto fail;
 282         }
 283         return NT_STATUS_OK;
 284
 285  fail:
 286         talloc_free(pipe_sock);
 287         return status;
 288 }