rpc_message.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

        ((*Header)->common.frag_len - hdr_length < header_auth_len)) {
      WARN("frag_len %d too small for hdr_length %d and auth_len %d\n",
        (*Header)->common.frag_len, hdr_length, header_auth_len);
      status = RPC_S_PROTOCOL_ERROR;
      goto fail;
    }

    if ((*Header)->common.auth_len != auth_length) {
      WARN("auth_len header field changed from %ld to %d\n",
        auth_length, (*Header)->common.auth_len);
      status = RPC_S_PROTOCOL_ERROR;
      goto fail;
    }

    if (((*Header)->common.flags & RPC_FLG_FIRST) != first_flag) {
      TRACE("invalid packet flags\n");
      status = RPC_S_PROTOCOL_ERROR;
      goto fail;
    }

    data_length = (*Header)->common.frag_len - hdr_length - header_auth_len;
    if (data_length + buffer_length > pMsg->BufferLength) {
      TRACE("allocation hint exceeded, new buffer length = %ld\n",
        data_length + buffer_length);
      pMsg->BufferLength = data_length + buffer_length;
      status = I_RpcReAllocateBuffer(pMsg);
      if (status != RPC_S_OK) goto fail;
    }

    if (data_length == 0) dwRead = 0; else
    dwRead = rpcrt4_conn_read(Connection,
        (unsigned char *)pMsg->Buffer + buffer_length, data_length);
    if (dwRead != data_length) {
      WARN("bad data length, %d/%ld\n", dwRead, data_length);
      status = RPC_S_PROTOCOL_ERROR;
      goto fail;
    }

    if (header_auth_len) {
      if (header_auth_len < sizeof(RpcAuthVerifier)) {
        WARN("bad auth verifier length %d\n", header_auth_len);
        status = RPC_S_PROTOCOL_ERROR;
        goto fail;
      }

      /* FIXME: we should accumulate authentication data for the bind,
       * bind_ack, alter_context and alter_context_response if necessary.
       * however, the details of how this is done is very sketchy in the
       * DCE/RPC spec. for all other packet types that have authentication
       * verifier data then it is just duplicated in all the fragments */
      dwRead = rpcrt4_conn_read(Connection, auth_data, header_auth_len);
      if (dwRead != header_auth_len) {
        WARN("bad authentication data length, %d/%d\n", dwRead,
          header_auth_len);
        status = RPC_S_PROTOCOL_ERROR;
        goto fail;
      }

      /* these packets are handled specially, not by the generic SecurePacket
       * function */
      if ((common_hdr.ptype != PKT_BIND) &&
          (common_hdr.ptype != PKT_BIND_ACK) &&
          (common_hdr.ptype != PKT_AUTH3))
        status = RPCRT4_SecurePacket(Connection, SECURE_PACKET_RECEIVE,
            *Header, hdr_length,
            (unsigned char *)pMsg->Buffer + buffer_length, data_length,
            (RpcAuthVerifier *)auth_data,
            (unsigned char *)auth_data + sizeof(RpcAuthVerifier),
            header_auth_len - sizeof(RpcAuthVerifier));
    }

    buffer_length += data_length;
    if (!((*Header)->common.flags & RPC_FLG_LAST)) {
      TRACE("next header\n");

      /* read the header of next packet */
      dwRead = rpcrt4_conn_read(Connection, *Header, hdr_length);
      if (dwRead != hdr_length) {
        WARN("invalid packet header size (%d)\n", dwRead);
        status = RPC_S_PROTOCOL_ERROR;
        goto fail;
      }

      first_flag = 0;
    } else {
      break;
    }
  }
  pMsg->BufferLength = buffer_length;

  /* respond to authorization request */
  if (common_hdr.ptype == PKT_BIND_ACK && auth_length > sizeof(RpcAuthVerifier))
  {
    status = RPCRT_AuthorizeConnection(Connection,
                                       auth_data + sizeof(RpcAuthVerifier),
                                       auth_length);
    if (status)
        goto fail;
  }

  /* success */
  status = RPC_S_OK;

fail:
  if (status != RPC_S_OK) {
    RPCRT4_FreeHeader(*Header);
    *Header = NULL;
  }
  HeapFree(GetProcessHeap(), 0, auth_data);
  return status;
}

/***********************************************************************
 *           I_RpcGetBuffer [RPCRT4.@]
 *
 * Allocates a buffer for use by I_RpcSend or I_RpcSendReceive and binds to the
 * server interface.
 *
 * PARAMS
 *  pMsg [I/O] RPC message information.
 *
 * RETURNS
 *  Success: RPC_S_OK.
 *  Failure: RPC_S_INVALID_BINDING if pMsg->Handle is invalid.
 *           RPC_S_SERVER_UNAVAILABLE if unable to connect to server.
 *           ERROR_OUTOFMEMORY if buffer allocation failed.
 *
 * NOTES
 *  The pMsg->BufferLength field determines the size of the buffer to allocate,
 *  in bytes.
 *
 *  Use I_RpcFreeBuffer() to unbind from the server and free the message buffer.
 *
 * SEE ALSO
 *  I_RpcFreeBuffer(), I_RpcSend(), I_RpcReceive(), I_RpcSendReceive().
 */
RPC_STATUS WINAPI I_RpcGetBuffer(PRPC_MESSAGE pMsg)
{
  TRACE("(%p): BufferLength=%d\n", pMsg, pMsg->BufferLength);
  /* FIXME: pfnAllocate? */
  pMsg->Buffer = HeapAlloc(GetProcessHeap(), 0, pMsg->BufferLength);

  TRACE("Buffer=%p\n", pMsg->Buffer);
  /* FIXME: which errors to return? */
  return pMsg->Buffer ? S_OK : E_OUTOFMEMORY;
}

/***********************************************************************
 *           I_RpcReAllocateBuffer (internal)
 */
static RPC_STATUS I_RpcReAllocateBuffer(PRPC_MESSAGE pMsg)
{
  TRACE("(%p): BufferLength=%d\n", pMsg, pMsg->BufferLength);
  pMsg->Buffer = HeapReAlloc(GetProcessHeap(), 0, pMsg->Buffer, pMsg->BufferLength);

  TRACE("Buffer=%p\n", pMsg->Buffer);
  return pMsg->Buffer ? RPC_S_OK : RPC_S_OUT_OF_RESOURCES;
}

/***********************************************************************
 *           I_RpcFreeBuffer [RPCRT4.@]
 *
 * Frees a buffer allocated by I_RpcGetBuffer or I_RpcReceive and unbinds from
 * the server interface.
 *
 * PARAMS
 *  pMsg [I/O] RPC message information.
 *
 * RETURNS
 *  RPC_S_OK.
 *
 * SEE ALSO
 *  I_RpcGetBuffer(), I_RpcReceive().
 */
RPC_STATUS WINAPI I_RpcFreeBuffer(PRPC_MESSAGE pMsg)
{
  TRACE("(%p) Buffer=%p\n", pMsg, pMsg->Buffer);
  /* FIXME: pfnFree? */
  HeapFree(GetProcessHeap(), 0, pMsg->Buffer);
  pMsg->Buffer = NULL;
  return S_OK;
}

/***********************************************************************
 *           I_RpcSend [RPCRT4.@]
 *
 * Sends a message to the server.
 *
 * PARAMS
 *  pMsg [I/O] RPC message information.
 *
 * RETURNS
 *  Unknown.
 *
 * NOTES
 *  The buffer must have been allocated with I_RpcGetBuffer().
 *
 * SEE ALSO
 *  I_RpcGetBuffer(), I_RpcReceive(), I_RpcSendReceive().
 */
RPC_STATUS WINAPI I_RpcSend(PRPC_MESSAGE pMsg)
{
  RpcBinding* bind = (RpcBinding*)pMsg->Handle;
  RpcConnection* conn;
  RPC_CLIENT_INTERFACE* cif = NULL;
  RPC_STATUS status;
  RpcPktHdr *hdr;

  TRACE("(%p)\n", pMsg);
  if (!bind || bind->server) return RPC_S_INVALID_BINDING;

  cif = pMsg->RpcInterfaceInformation;
  if (!cif) return RPC_S_INTERFACE_NOT_FOUND; /* ? */

  if (!bind->Endpoint || !bind->Endpoint[0])
  {
    TRACE("automatically resolving partially bound binding\n");
    status = RpcEpResolveBinding(bind, cif);
    if (status != RPC_S_OK) return status;
  }

  status = RPCRT4_OpenBinding(bind, &conn, &cif->TransferSyntax,
                              &cif->InterfaceId);
  if (status != RPC_S_OK) return status;

  hdr = RPCRT4_BuildRequestHeader(pMsg->DataRepresentation,
                                  pMsg->BufferLength, pMsg->ProcNum,
                                  &bind->ObjectUuid);
  if (!hdr)
  {
    RPCRT4_CloseBinding(bind, conn);
    return ERROR_OUTOFMEMORY;
  }
  hdr->common.call_id = conn->NextCallId++;

  status = RPCRT4_Send(conn, hdr, pMsg->Buffer, pMsg->BufferLength);

  RPCRT4_FreeHeader(hdr);

  /* save the connection, so the response can be read from it */
  pMsg->ReservedForRuntime = conn;
  return status;
}

/* is this status something that the server can't recover from? */
static inline BOOL is_hard_error(RPC_STATUS status)
{
    switch (status)
    {
    case 0: /* user-defined fault */
    case ERROR_ACCESS_DENIED:
    case ERROR_INVALID_PARAMETER:
    case RPC_S_PROTOCOL_ERROR:
    case RPC_S_CALL_FAILED:
    case RPC_S_CALL_FAILED_DNE:
        return TRUE;
    default:
        return FALSE;
    }
}

/***********************************************************************
 *           I_RpcReceive [RPCRT4.@]
 */
RPC_STATUS WINAPI I_RpcReceive(PRPC_MESSAGE pMsg)
{
  RpcBinding* bind = (RpcBinding*)pMsg->Handle;
  RpcConnection* conn;
  RPC_CLIENT_INTERFACE* cif = NULL;
  RPC_SERVER_INTERFACE* sif = NULL;
  RPC_STATUS status;
  RpcPktHdr *hdr = NULL;

  TRACE("(%p)\n", pMsg);
  if (!bind) return RPC_S_INVALID_BINDING;

  if (pMsg->ReservedForRuntime) {
    conn = pMsg->ReservedForRuntime;
    pMsg->ReservedForRuntime = NULL;
  } else {
    if (bind->server) {
      sif = pMsg->RpcInterfaceInformation;
      if (!sif) return RPC_S_INTERFACE_NOT_FOUND; /* ? */
      status = RPCRT4_OpenBinding(bind, &conn, &sif->TransferSyntax,
                                  &sif->InterfaceId);
    } else {
      cif = pMsg->RpcInterfaceInformation;
      if (!cif) return RPC_S_INTERFACE_NOT_FOUND; /* ? */

      if (!bind->Endpoint || !bind->Endpoint[0])
      {
        TRACE("automatically resolving partially bound binding\n");
        status = RpcEpResolveBinding(bind, cif);
        if (status != RPC_S_OK) return status;
      }

      status = RPCRT4_OpenBinding(bind, &conn, &cif->TransferSyntax,
                                  &cif->InterfaceId);
    }
    if (status != RPC_S_OK) return status;
  }

  status = RPCRT4_Receive(conn, &hdr, pMsg);
  if (status != RPC_S_OK) {
    WARN("receive failed with error %lx\n", status);
    goto fail;
  }

  switch (hdr->common.ptype) {
  case PKT_RESPONSE:
    if (bind->server) {
        status = RPC_S_PROTOCOL_ERROR;
        goto fail;
    }
    break;
  case PKT_REQUEST:
    if (!bind->server) {
        status = RPC_S_PROTOCOL_ERROR;
        goto fail;
    }
    break;
  case PKT_FAULT:
    ERR ("we got fault packet with status 0x%lx\n", hdr->fault.status);
    status = NCA2RPC_STATUS(hdr->fault.status);
    if (is_hard_error(status))
        goto fail;
    break;
  default:
    WARN("bad packet type %d\n", hdr->common.ptype);
    status = RPC_S_PROTOCOL_ERROR;
    goto fail;
  }

  /* success */
  RPCRT4_CloseBinding(bind, conn);
  RPCRT4_FreeHeader(hdr);
  return status;

fail:
  RPCRT4_FreeHeader(hdr);
  RPCRT4_DestroyConnection(conn);
  return status;
}

/***********************************************************************
 *           I_RpcSendReceive [RPCRT4.@]
 *
 * Sends a message to the server and receives the response.
 *
 * PARAMS
 *  pMsg [I/O] RPC message information.
 *
 * RETURNS
 *  Success: RPC_S_OK.
 *  Failure: Any error code.
 *
 * NOTES
 *  The buffer must have been allocated with I_RpcGetBuffer().
 *
 * SEE ALSO
 *  I_RpcGetBuffer(), I_RpcSend(), I_RpcReceive().
 */
RPC_STATUS WINAPI I_RpcSendReceive(PRPC_MESSAGE pMsg)
{
  RPC_STATUS status;
  RPC_MESSAGE original_message;

  TRACE("(%p)\n", pMsg);

  original_message = *pMsg;
  status = I_RpcSend(pMsg);
  if (status == RPC_S_OK)
    status = I_RpcReceive(pMsg);
  /* free the buffer replaced by a new buffer in I_RpcReceive */
  if (status == RPC_S_OK)
    I_RpcFreeBuffer(&original_message);
  return status;
}