Re: [Patch] [Patch] MdeModulePkg: Add error handling when IP address is Class E

["Wu, Jiaxin" <jiaxin.wu@intel.com>]

Reviewed-by: Jiaxin Wu <jiaxin.wu@intel.com>

Please update the copyright before commit the patch.

Thanks,
Jiaxin

> -----Original Message-----
> From: Wang, Fan
> Sent: Tuesday, January 2, 2018 10:45 AM
> To: edk2-devel@lists.01.org
> Cc: Wang, Fan <fan.wang@intel.com>; Wu, Jiaxin <jiaxin.wu@intel.com>; Ye,
> Ting <ting.ye@intel.com>; Fu, Siyuan <siyuan.fu@intel.com>
> Subject: [Patch] [Patch] MdeModulePkg: Add error handling when IP
> address is Class E
> 
> From: Wang Fan <fan.wang@intel.com>
> 
> The Dhcp4.TransmitReceive() API should be able to use at any time according
> to UEFI spec. While in classless addressing network, the netmask must be
> explicitly provided together with the station address.
> But if the DHCP instance haven't be configured with a valid netmask, we
> need
> compute it according to the classful addressing rule. In such case, if the
> user configures with class E IP address, ASSERT will happen, we need to
> handle
> this case and return error status code.
> 
> Cc: Jiaxin Wu <jiaxin.wu@intel.com>
> Cc: Ye Ting <ting.ye@intel.com>
> Cc: Fu Siyuan <siyuan.fu@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Wang Fan <fan.wang@intel.com>
> ---
>  MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c | 13
> +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
> b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
> index aad6674..b95aede 100644
> --- a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
> +++ b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
> @@ -1184,12 +1184,14 @@ EfiDhcp4Build (
>    Callback by UdpIoCreatePort() when creating UdpIo for this Dhcp4 instance.
> 
>    @param[in] UdpIo      The UdpIo being created.
>    @param[in] Context    Dhcp4 instance.
> 
> -  @retval EFI_SUCCESS   UdpIo is configured successfully.
> -  @retval other         Other error occurs.
> +  @retval EFI_SUCCESS              UdpIo is configured successfully.
> +  @retval EFI_INVALID_PARAMETER    Class E IP address is not supported or
> other parameters
> +                                   are not valid.
> +  @retval other                    Other error occurs.
>  **/
>  EFI_STATUS
>  EFIAPI
>  Dhcp4InstanceConfigUdpIo (
>    IN UDP_IO       *UdpIo,
> @@ -1227,11 +1229,18 @@ Dhcp4InstanceConfigUdpIo (
>      // provided together with the station address.
>      // If the DHCP instance haven't be configured with a valid netmask, we
> could only
>      // compute it according to the classful addressing rule.
>      //
>      Class = NetGetIpClass (ClientAddr);
> +    //
> +    //  Class E IP address is not supported here!
> +    //
>      ASSERT (Class < IP4_ADDR_CLASSE);
> +    if (Class >= IP4_ADDR_CLASSE) {
> +      return EFI_INVALID_PARAMETER;
> +    }
> +
>      SubnetMask = gIp4AllMasks[Class << 3];
>    } else {
>      SubnetMask = DhcpSb->Netmask;
>    }
> 
> --
> 1.9.5.msysgit.1