Re: [Patch 2/2] NetworkPkg: Read TlsCipherList variable and configure it for HTTPS session.

[Laszlo Ersek <lersek@redhat.com>]

On 02/09/18 04:59, Jiaxin Wu wrote:
> This patch is to read the TlsCipherList variable and configure it for the
> later HTTPS session.
> 
> If the variable is not set by any platform, EFI_NOT_FOUND will be returned
> from GetVariable service. In such a case, the default CipherList created in
> TlsDxe driver will be used.
> 
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Kinney Michael D <michael.d.kinney@intel.com>
> Cc: Zimmer Vincent <vincent.zimmer@intel.com>
> Cc: Yao Jiewen <jiewen.yao@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: Wu Jiaxin <jiaxin.wu@intel.com>
> ---
>  NetworkPkg/HttpDxe/HttpDriver.h   |  3 +-
>  NetworkPkg/HttpDxe/HttpDxe.inf    |  3 +-
>  NetworkPkg/HttpDxe/HttpsSupport.c | 92 ++++++++++++++++++++++++++++++++++++++-
>  3 files changed, 95 insertions(+), 3 deletions(-)
> 
> diff --git a/NetworkPkg/HttpDxe/HttpDriver.h b/NetworkPkg/HttpDxe/HttpDriver.h
> index 93a412a..eba7d32 100644
> --- a/NetworkPkg/HttpDxe/HttpDriver.h
> +++ b/NetworkPkg/HttpDxe/HttpDriver.h
> @@ -1,9 +1,9 @@
>  /** @file
>    The header files of the driver binding and service binding protocol for HttpDxe driver.
>  
> -  Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.<BR>
> +  Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
>    (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
>  
>    This program and the accompanying materials
>    are licensed and made available under the terms and conditions of the BSD License
>    which accompanies this distribution.  The full text of the license may be found at
> @@ -59,10 +59,11 @@
>  // Produced Protocols
>  //
>  #include <Protocol/Http.h>
>  
>  #include <Guid/TlsAuthentication.h>
> +#include <Guid/TlsCipherList.h>
>  
>  #include <IndustryStandard/Tls1.h>
>  
>  //
>  // Driver Version
> diff --git a/NetworkPkg/HttpDxe/HttpDxe.inf b/NetworkPkg/HttpDxe/HttpDxe.inf
> index 20075f5..b1d7bd2 100644
> --- a/NetworkPkg/HttpDxe/HttpDxe.inf
> +++ b/NetworkPkg/HttpDxe/HttpDxe.inf
> @@ -1,9 +1,9 @@
>  ## @file
>  #  Implementation of EFI HTTP protocol interfaces.
>  #
> -#  Copyright (c) 2015 - 2017, Intel Corporation. All rights reserved.<BR>
> +#  Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
>  #
>  #  This program and the accompanying materials
>  #  are licensed and made available under the terms and conditions of the BSD License
>  #  which accompanies this distribution. The full text of the license may be found at
>  #  http://opensource.org/licenses/bsd-license.php.
> @@ -72,10 +72,11 @@
>    gEfiTlsProtocolGuid                              ## SOMETIMES_CONSUMES
>    gEfiTlsConfigurationProtocolGuid                 ## SOMETIMES_CONSUMES
>  
>  [Guids]
>    gEfiTlsCaCertificateGuid                         ## SOMETIMES_CONSUMES  ## Variable:L"TlsCaCertificate"
> +  gTlsCipherListGuid                               ## SOMETIMES_CONSUMES  ## Variable:L"TlsCipherList"
>  
>  [Pcd]
>    gEfiNetworkPkgTokenSpaceGuid.PcdAllowHttpConnections       ## CONSUMES
>    gEfiNetworkPkgTokenSpaceGuid.PcdHttpsAuthenticationMode    ## SOMETIMES_CONSUMES
>    gEfiNetworkPkgTokenSpaceGuid.PcdHttpsHostPublicCert        ## SOMETIMES_CONSUMES
> diff --git a/NetworkPkg/HttpDxe/HttpsSupport.c b/NetworkPkg/HttpDxe/HttpsSupport.c
> index 288082a..62cb867 100644
> --- a/NetworkPkg/HttpDxe/HttpsSupport.c
> +++ b/NetworkPkg/HttpDxe/HttpsSupport.c
> @@ -1,9 +1,9 @@
>  /** @file
>    Miscellaneous routines specific to Https for HttpDxe driver.
>  
> -Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2016 - 2018, Intel Corporation. All rights reserved.<BR>
>  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
>  This program and the accompanying materials
>  are licensed and made available under the terms and conditions of the BSD License
>  which accompanies this distribution.  The full text of the license may be found at
>  http://opensource.org/licenses/bsd-license.php
> @@ -492,10 +492,91 @@ TlsConfigCertificate (
>    
>    return Status;
>  }
>  
>  /**
> +  Read the TlsCipherList variable and configure it for HTTPS session.
> +
> +  @param[in, out]  HttpInstance       The HTTP instance private data.
> +
> +  @retval EFI_SUCCESS            The prefered TLS CipherList is configured.
> +  @retval EFI_NOT_FOUND          Fail to get 'TlsCipherList' variable.
> +  @retval EFI_INVALID_PARAMETER  The contents of variable are invalid.
> +  @retval EFI_OUT_OF_RESOURCES   Can't allocate memory resources.
> +
> +  @retval Others                 Other error as indicated.
> +
> +**/
> +EFI_STATUS
> +TlsConfigCipherList (
> +  IN OUT HTTP_PROTOCOL      *HttpInstance
> +  )
> +{
> +  EFI_STATUS          Status;
> +  UINT8               *CipherList;
> +  UINTN               CipherListSize;
> +
> +  CipherList     = NULL;
> +  CipherListSize = 0;
> +
> +  //
> +  // Try to read the TlsCipherList variable.
> +  //
> +  Status  = gRT->GetVariable (
> +                   EDKII_TLS_CIPHER_LIST_VARIABLE,
> +                   &gTlsCipherListGuid,
> +                   NULL,
> +                   &CipherListSize,
> +                   NULL
> +                   );
> +
> +  if (EFI_ERROR (Status) && Status != EFI_BUFFER_TOO_SMALL) {
> +    return Status;
> +  }

I think the above GetVariable service call can never succeed. What about:

  ASSERT (EFI_ERROR (Status));
  if (Status != EFI_BUFFER_TOO_SMALL) {
    return Status;
  }

Not very important (the behavior won't change), but I think this is
better for documentation purposes.

The patch looks good to me otherwise.

Thank you!
Laszlo


> +
> +  if (CipherListSize % sizeof (EFI_TLS_CIPHER) != 0) {
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  //
> +  // Allocate buffer and read the config variable.
> +  //
> +  CipherList = AllocatePool (CipherListSize);
> +  if (CipherList == NULL) {
> +    return EFI_OUT_OF_RESOURCES;
> +  }
> +
> +  Status = gRT->GetVariable (
> +                  EDKII_TLS_CIPHER_LIST_VARIABLE,
> +                  &gTlsCipherListGuid,
> +                  NULL,
> +                  &CipherListSize,
> +                  CipherList
> +                  );
> +  if (EFI_ERROR (Status)) {
> +    //
> +    // GetVariable still error or the variable is corrupted.
> +    //
> +    goto ON_EXIT;
> +  }
> +
> +  ASSERT (CipherList != NULL);
> +
> +  Status = HttpInstance->Tls->SetSessionData (
> +                                HttpInstance->Tls,
> +                                EfiTlsCipherList,
> +                                CipherList,
> +                                CipherListSize
> +                                );
> +
> +ON_EXIT:  
> +  FreePool (CipherList);
> +  
> +  return Status;
> +}
> +
> +/**
>    Configure TLS session data.
>  
>    @param[in, out]  HttpInstance       The HTTP instance private data.
>  
>    @retval EFI_SUCCESS            TLS session data is configured.
> @@ -551,10 +632,19 @@ TlsConfigureSession (
>    if (EFI_ERROR (Status)) {
>      return Status;
>    }
>  
>    //
> +  // Tls Cipher List
> +  //
> +  Status = TlsConfigCipherList (HttpInstance);
> +  if (EFI_ERROR (Status) && Status != EFI_NOT_FOUND) {
> +    DEBUG ((EFI_D_ERROR, "TlsConfigCipherList: return %r error.\n", Status));
> +    return Status;
> +  }
> +
> +  //
>    // Tls Config Certificate
>    //
>    Status = TlsConfigCertificate (HttpInstance);
>    if (EFI_ERROR (Status)) {
>      DEBUG ((EFI_D_ERROR, "TlsConfigCertificate: return %r error.\n", Status));
>