rpc.c

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{
    const char *end = (char *)msg->Buffer + msg->BufferLength;

    *first_wire_orpc_extent = NULL;

    if (msg->BufferLength < FIELD_OFFSET(ORPCTHIS, extensions) + 4)
    {
        ERR("invalid buffer length\n");
        return RPC_E_INVALID_HEADER;
    }

    memcpy(orpcthis, msg->Buffer, FIELD_OFFSET(ORPCTHIS, extensions));
    msg->Buffer = (char *)msg->Buffer + FIELD_OFFSET(ORPCTHIS, extensions);

    if ((const char *)msg->Buffer + sizeof(DWORD) > end)
        return RPC_E_INVALID_HEADER;

    if (*(DWORD *)msg->Buffer)
        orpcthis->extensions = orpc_ext_array;
    else
        orpcthis->extensions = NULL;

    msg->Buffer = (char *)msg->Buffer + sizeof(DWORD);

    if (orpcthis->extensions)
    {
        HRESULT hr = unmarshal_ORPC_EXTENT_ARRAY(msg, end, orpc_ext_array,
                                                 first_wire_orpc_extent);
        if (FAILED(hr))
            return hr;
    }

    if ((orpcthis->version.MajorVersion != COM_MAJOR_VERSION) ||
        (orpcthis->version.MinorVersion > COM_MINOR_VERSION))
    {
        ERR("COM version {%d, %d} not supported\n",
            orpcthis->version.MajorVersion, orpcthis->version.MinorVersion);
        return RPC_E_VERSION_MISMATCH;
    }

    if (orpcthis->flags & ~(ORPCF_LOCAL|ORPCF_RESERVED1|ORPCF_RESERVED2|ORPCF_RESERVED3|ORPCF_RESERVED4))
    {
        ERR("invalid flags 0x%lx\n", orpcthis->flags & ~(ORPCF_LOCAL|ORPCF_RESERVED1|ORPCF_RESERVED2|ORPCF_RESERVED3|ORPCF_RESERVED4));
        return RPC_E_INVALID_HEADER;
    }

    return S_OK;
}

static HRESULT unmarshal_ORPCTHAT(RPC_MESSAGE *msg, ORPCTHAT *orpcthat,
                                  ORPC_EXTENT_ARRAY *orpc_ext_array, WIRE_ORPC_EXTENT **first_wire_orpc_extent)
{
    const char *end = (char *)msg->Buffer + msg->BufferLength;

    *first_wire_orpc_extent = NULL;

    if (msg->BufferLength < FIELD_OFFSET(ORPCTHAT, extensions) + 4)
    {
        ERR("invalid buffer length\n");
        return RPC_E_INVALID_HEADER;
    }

    memcpy(orpcthat, msg->Buffer, FIELD_OFFSET(ORPCTHAT, extensions));
    msg->Buffer = (char *)msg->Buffer + FIELD_OFFSET(ORPCTHAT, extensions);

    if ((const char *)msg->Buffer + sizeof(DWORD) > end)
        return RPC_E_INVALID_HEADER;

    if (*(DWORD *)msg->Buffer)
        orpcthat->extensions = orpc_ext_array;
    else
        orpcthat->extensions = NULL;

    msg->Buffer = (char *)msg->Buffer + sizeof(DWORD);

    if (orpcthat->extensions)
    {
        HRESULT hr = unmarshal_ORPC_EXTENT_ARRAY(msg, end, orpc_ext_array,
                                                 first_wire_orpc_extent);
        if (FAILED(hr))
            return hr;
    }

    if (orpcthat->flags & ~(ORPCF_LOCAL|ORPCF_RESERVED1|ORPCF_RESERVED2|ORPCF_RESERVED3|ORPCF_RESERVED4))
    {
        ERR("invalid flags 0x%lx\n", orpcthat->flags & ~(ORPCF_LOCAL|ORPCF_RESERVED1|ORPCF_RESERVED2|ORPCF_RESERVED3|ORPCF_RESERVED4));
        return RPC_E_INVALID_HEADER;
    }

    return S_OK;
}

void RPC_ExecuteCall(struct dispatch_params *params)
{
    struct message_state *message_state = NULL;
    RPC_MESSAGE *msg = (RPC_MESSAGE *)params->msg;
    char *original_buffer = msg->Buffer;
    ORPCTHIS orpcthis;
    ORPC_EXTENT_ARRAY orpc_ext_array;
    WIRE_ORPC_EXTENT *first_wire_orpc_extent;
    GUID old_causality_id;

    /* handle ORPCTHIS and server extensions */

    params->hr = unmarshal_ORPCTHIS(msg, &orpcthis, &orpc_ext_array, &first_wire_orpc_extent);
    if (params->hr != S_OK)
    {
        msg->Buffer = original_buffer;
        goto exit;
    }

    message_state = HeapAlloc(GetProcessHeap(), 0, sizeof(*message_state));
    if (!message_state)
    {
        params->hr = E_OUTOFMEMORY;
        msg->Buffer = original_buffer;
        goto exit;
    }

    message_state->prefix_data_len = (char *)msg->Buffer - original_buffer;
    message_state->binding_handle = msg->Handle;

    message_state->channel_hook_info.iid = params->iid;
    message_state->channel_hook_info.cbSize = sizeof(message_state->channel_hook_info);
    message_state->channel_hook_info.uCausality = orpcthis.cid;
    message_state->channel_hook_info.dwServerPid = GetCurrentProcessId();
    message_state->channel_hook_info.iMethod = msg->ProcNum;
    message_state->channel_hook_info.pObject = params->iface;

    if (orpcthis.extensions && first_wire_orpc_extent &&
        orpcthis.extensions->size)
        ChannelHooks_ServerNotify(&message_state->channel_hook_info, msg->DataRepresentation, first_wire_orpc_extent, orpcthis.extensions->size);

    msg->Handle = message_state;
    msg->BufferLength -= message_state->prefix_data_len;

    /* call message filter */

    if (COM_CurrentApt()->filter)
    {
        DWORD handlecall;
        INTERFACEINFO interface_info;
        CALLTYPE calltype;

        interface_info.pUnk = params->iface;
        interface_info.iid = params->iid;
        interface_info.wMethod = msg->ProcNum;

        if (IsEqualGUID(&orpcthis.cid, &COM_CurrentInfo()->causality_id))
            calltype = CALLTYPE_NESTED;
        else if (COM_CurrentInfo()->pending_call_count_server == 0)
            calltype = CALLTYPE_TOPLEVEL;
        else
            calltype = CALLTYPE_TOPLEVEL_CALLPENDING;

        handlecall = IMessageFilter_HandleInComingCall(COM_CurrentApt()->filter,
                                                       calltype,
                                                       (HTASK)GetCurrentProcessId(),
                                                       0 /* FIXME */,
                                                       &interface_info);
        TRACE("IMessageFilter_HandleInComingCall returned %d\n", handlecall);
        switch (handlecall)
        {
        case SERVERCALL_REJECTED:
            params->hr = RPC_E_CALL_REJECTED;
            goto exit_reset_state;
        case SERVERCALL_RETRYLATER:
#if 0 /* FIXME: handle retries on the client side before enabling this code */
            params->hr = RPC_E_RETRY;
            goto exit_reset_state;
#else
            FIXME("retry call later not implemented\n");
            break;
#endif
        case SERVERCALL_ISHANDLED:
        default:
            break;
        }
    }

    /* invoke the method */

    /* save the old causality ID - note: any calls executed while processing
     * messages received during the SendReceive will appear to originate from
     * this call - this should be checked with what Windows does */
    old_causality_id = COM_CurrentInfo()->causality_id;
    COM_CurrentInfo()->causality_id = orpcthis.cid;
    COM_CurrentInfo()->pending_call_count_server++;
    params->hr = IRpcStubBuffer_Invoke(params->stub, params->msg, params->chan);
    COM_CurrentInfo()->pending_call_count_server--;
    COM_CurrentInfo()->causality_id = old_causality_id;

exit_reset_state:
    message_state = (struct message_state *)msg->Handle;
    msg->Handle = message_state->binding_handle;
    msg->Buffer = (char *)msg->Buffer - message_state->prefix_data_len;
    msg->BufferLength += message_state->prefix_data_len;

exit:
    HeapFree(GetProcessHeap(), 0, message_state);
    IRpcStubBuffer_Release(params->stub);
    IRpcChannelBuffer_Release(params->chan);
    if (params->handle) SetEvent(params->handle);
}

static void __RPC_STUB dispatch_rpc(RPC_MESSAGE *msg)
{
    struct dispatch_params *params;
    APARTMENT *apt;
    IPID ipid;
    HRESULT hr;

    RpcBindingInqObject(msg->Handle, &ipid);

    TRACE("ipid = %s, iMethod = %d\n", debugstr_guid(&ipid), msg->ProcNum);

    params = HeapAlloc(GetProcessHeap(), 0, sizeof(*params));
    if (!params)
    {
        RpcRaiseException(E_OUTOFMEMORY);
        return;
    }

    hr = ipid_get_dispatch_params(&ipid, &apt, &params->stub, &params->chan,
                                  &params->iid, &params->iface);
    if (hr != S_OK)
    {
        ERR("no apartment found for ipid %s\n", debugstr_guid(&ipid));
        HeapFree(GetProcessHeap(), 0, params);
        RpcRaiseException(hr);
        return;
    }

    params->msg = (RPCOLEMESSAGE *)msg;
    params->status = RPC_S_OK;
    params->hr = S_OK;
    params->handle = NULL;

    /* Note: this is the important difference between STAs and MTAs - we
     * always execute RPCs to STAs in the thread that originally created the
     * apartment (i.e. the one that pumps messages to the window) */
    if (!apt->multi_threaded)
    {
        params->handle = CreateEventW(NULL, FALSE, FALSE, NULL);

        TRACE("Calling apartment thread 0x%08x...\n", apt->tid);

        if (PostMessageW(apartment_getwindow(apt), DM_EXECUTERPC, 0, (LPARAM)params))
            WaitForSingleObject(params->handle, INFINITE);
        else
        {
            ERR("PostMessage failed with error %u\n", GetLastError());
            IRpcChannelBuffer_Release(params->chan);
            IRpcStubBuffer_Release(params->stub);
        }
        CloseHandle(params->handle);
    }
    else
    {
        BOOL joined = FALSE;
        if (!COM_CurrentInfo()->apt)
        {
            apartment_joinmta();
            joined = TRUE;
        }
        RPC_ExecuteCall(params);
        if (joined)
        {
            apartment_release(COM_CurrentInfo()->apt);
            COM_CurrentInfo()->apt = NULL;
        }
    }

    hr = params->hr;
    HeapFree(GetProcessHeap(), 0, params);

    apartment_release(apt);

    /* if IRpcStubBuffer_Invoke fails, we should raise an exception to tell
     * the RPC runtime that the call failed */
    if (hr) RpcRaiseException(hr);
}

/* stub registration */
HRESULT RPC_RegisterInterface(REFIID riid)
{
    struct registered_if *rif;
    BOOL found = FALSE;
    HRESULT hr = S_OK;
    
    TRACE("(%s)\n", debugstr_guid(riid));

    EnterCriticalSection(&csRegIf);
    LIST_FOR_EACH_ENTRY(rif, &registered_interfaces, struct registered_if, entry)
    {
        if (IsEqualGUID(&rif->If.InterfaceId.SyntaxGUID, riid))
        {
            rif->refs++;
            found = TRUE;
            break;
        }
    }
    if (!found)
    {
        TRACE("Creating new interface\n");

        rif = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*rif));
        if (rif)
        {
            RPC_STATUS status;

            rif->refs = 1;
            rif->If.Length = sizeof(RPC_SERVER_INTERFACE);
            /* RPC interface ID = COM interface ID */
            rif->If.InterfaceId.SyntaxGUID = *riid;
            rif->If.DispatchTable = &rpc_dispatch;
            /* all other fields are 0, including the version asCOM objects
             * always have a version of 0.0 */
            status = RpcServerRegisterIfEx(
                (RPC_IF_HANDLE)&rif->If,
                NULL, NULL,
                RPC_IF_OLE | RPC_IF_AUTOLISTEN,
                RPC_C_LISTEN_MAX_CALLS_DEFAULT,
                NULL);
            if (status == RPC_S_OK)
                list_add_tail(&registered_interfaces, &rif->entry);
            else
            {
                ERR("RpcServerRegisterIfEx failed with error %ld\n", status);
                HeapFree(GetProcessHeap(), 0, rif);
                hr = HRESULT_FROM_WIN32(status);
            }
        }
        else
            hr = E_OUTOFMEMORY;
    }
    LeaveCriticalSection(&csRegIf);
    return hr;
}

/* stub unregistration */
void RPC_UnregisterInterface(REFIID riid)
{
    struct registered_if *rif;
    EnterCriticalSection(&csRegIf);
    LIST_FOR_EACH_ENTRY(rif, &registered_interfaces, struct registered_if, entry)
    {
        if (IsEqualGUID(&rif->If.InterfaceId.SyntaxGUID, riid))
        {
            if (!--rif->refs)
            {
                RpcServerUnregisterIf((RPC_IF_HANDLE)&rif->If, NULL, TRUE);
                list_remove(&rif->entry);
                HeapFree(GetProcessHeap(), 0, rif);
            }
            break;
        }
    }
    LeaveCriticalSection(&csRegIf);
}

/* get the info for an OXID, including the IPID for the rem unknown interface
 * and the string binding */
HRESULT RPC_ResolveOxid(OXID oxid, OXID_INFO *oxid_info)
{
    TRACE("%s\n", wine_dbgstr_longlong(oxid));

    oxid_info->dwTid = 0;
    oxid_info->dwPid = 0;
    oxid_info->dwAuthnHint = RPC_C_AUTHN_LEVEL_NONE;
    /* FIXME: this is a hack around not having an OXID resolver yet -
     * this function should contact the machine's OXID resolver and then it
     * should give us the IPID of the IRemUnknown interface */
    oxid_info->ipidRemUnknown.Data1 = 0xffffffff;
    oxid_info->ipidRemUnknown.Data2 = 0xffff;
    oxid_info->ipidRemUnknown.Data3 = 0xffff;
    memcpy(&oxid_info->ipidRemUnknown.Data4, &oxid, sizeof(OXID));
    oxid_info->psa = NULL /* FIXME */;