text: ## @file
  # This tool encodes and decodes GUIDed FFS sections for a GUID type of
  # EFI_CERT_TYPE_RSA2048_SHA256_GUID defined in the UEFI 2.4 Specification as
  #   {0xa7717414, 0xc616, 0x4977, {0x94, 0x20, 0x84, 0x47, 0x12, 0xa7, 0x35, 0xbf}}
  # This tool has been tested with OpenSSL 1.0.1e 11 Feb 2013
  #
  # Copyright (c) 2013 - 2014, 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
  #
  # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  #
  
  '''
  Rsa2048Sha256Sign
  '''
  
  import os
  import sys
  import argparse 
  import subprocess
  import uuid
  import struct
  import collections
  from Common.BuildVersion import gBUILD_VERSION
  
  #
  # Globals for help information
  #
  __prog__      = 'Rsa2048Sha256Sign'
  __version__   = '%s Version %s' % (__prog__, '0.9 ' + gBUILD_VERSION)
  __copyright__ = 'Copyright (c) 2013 - 2014, Intel Corporation. All rights reserved.'
  __usage__     = '%s -e|-d [options] <input_file>' % (__prog__)
  
  #
  # GUID for SHA 256 Hash Algorithm from UEFI Specification
  #
  EFI_HASH_ALGORITHM_SHA256_GUID = uuid.UUID('{51aa59de-fdf2-4ea3-bc63-875fb7842ee9}')
  
  #
  # Structure defintion to unpack EFI_CERT_BLOCK_RSA_2048_SHA256 from UEFI 2.4 Specification
  #
  #   typedef struct _EFI_CERT_BLOCK_RSA_2048_SHA256 {
  #     EFI_GUID HashType;
  #     UINT8 PublicKey[256];
  #     UINT8 Signature[256];
  #   } EFI_CERT_BLOCK_RSA_2048_SHA256;
  #
  EFI_CERT_BLOCK_RSA_2048_SHA256        = collections.namedtuple('EFI_CERT_BLOCK_RSA_2048_SHA256', ['HashType','PublicKey','Signature'])
  EFI_CERT_BLOCK_RSA_2048_SHA256_STRUCT = struct.Struct('16s256s256s')
  
  #
  # Filename of test signing private key that is stored in same directory as this tool
  #
  TEST_SIGNING_PRIVATE_KEY_FILENAME = 'TestSigningPrivateKey.pem'
  
  if __name__ == '__main__':
    #
    # Create command line argument parser object
    #  
    parser = argparse.ArgumentParser(prog=__prog__, version=__version__, usage=__usage__, description=__copyright__, conflict_handler='resolve')
    group = parser.add_mutually_exclusive_group(required=True)
    group.add_argument("-e", action="store_true", dest='Encode', help='encode file')
    group.add_argument("-d", action="store_true", dest='Decode', help='decode file')
    parser.add_argument("-o", "--output", dest='OutputFile', type=argparse.FileType('wb'), metavar='filename', help="specify the output filename", required=True)
    parser.add_argument("--private-key", dest='PrivateKeyFile', type=argparse.FileType('rb'), help="specify the private key filename.  If not specified, a test signing key is used.")
    parser.add_argument("-v", "--verbose", dest='Verbose', action="store_true", help="increase output messages")
    parser.add_argument("-q", "--quiet", dest='Quiet', action="store_true", help="reduce output messages")
    parser.add_argument("--debug", dest='Debug', type=int, metavar='[0-9]', choices=range(0,10), default=0, help="set debug level")
    parser.add_argument(metavar="input_file", dest='InputFile', type=argparse.FileType('rb'), help="specify the input filename")
  
    #
    # Parse command line arguments
    #  
    args = parser.parse_args()
  
    #
    # Generate file path to Open SSL command
    #
    OpenSslCommand = 'openssl'
    try:
      OpenSslPath = os.environ['OPENSSL_PATH']
      OpenSslCommand = os.path.join(OpenSslPath, OpenSslCommand)
    except:
      pass
  
    #
    # Verify that Open SSL command is available
    #
    try:
      Process = subprocess.Popen('%s version' % (OpenSslCommand), stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    except:  
      print 'ERROR: Open SSL command not available.  Please verify PATH or set OPENSSL_PATH'
      sys.exit(1)
      
    Version = Process.communicate()
    if Process.returncode <> 0:
      print 'ERROR: Open SSL command not available.  Please verify PATH or set OPENSSL_PATH'
      sys.exit(Process.returncode)
    print Version[0]
    
    #
    # Read input file into a buffer and save input filename
    #  
    args.InputFileName   = args.InputFile.name
    args.InputFileBuffer = args.InputFile.read()
    args.InputFile.close()
  
    #
    # Save output filename and close output file
    #
    args.OutputFileName = args.OutputFile.name
    args.OutputFile.close()
  
    #
    # Save private key filename and close private key file
    #
    try:
      args.PrivateKeyFileName = args.PrivateKeyFile.name
      args.PrivateKeyFile.close()
    except:
      try:
        #
        # Get path to currently executing script or executable
        #
        if hasattr(sys, 'frozen'):
            RsaToolPath = sys.executable
        else:
            RsaToolPath = sys.argv[0]
        if RsaToolPath.startswith('"'):
            RsaToolPath = RsaToolPath[1:]
        if RsaToolPath.endswith('"'):
            RsaToolPath = RsaToolPath[:-1]
        args.PrivateKeyFileName = os.path.join(os.path.dirname(os.path.realpath(RsaToolPath)), TEST_SIGNING_PRIVATE_KEY_FILENAME)
        args.PrivateKeyFile = open(args.PrivateKeyFileName, 'rb')
        args.PrivateKeyFile.close()
      except:
        print 'ERROR: test signing private key file %s missing' % (args.PrivateKeyFileName)
        sys.exit(1)
  
    #
    # Extract public key from private key into STDOUT
    #
    Process = subprocess.Popen('%s rsa -in "%s" -modulus -noout' % (OpenSslCommand, args.PrivateKeyFileName), stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    PublicKeyHexString = Process.communicate()[0].split('=')[1].strip()
    PublicKey = ''
    while len(PublicKeyHexString) > 0:
      PublicKey = PublicKey + chr(int(PublicKeyHexString[0:2],16))
      PublicKeyHexString=PublicKeyHexString[2:]
    if Process.returncode <> 0:
      sys.exit(Process.returncode)
    
    if args.Encode:
      # 
      # Sign the input file using the specified private key and capture signature from STDOUT
      #
      Process = subprocess.Popen('%s sha256 -sign "%s"' % (OpenSslCommand, args.PrivateKeyFileName), stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
      Signature = Process.communicate(input=args.InputFileBuffer)[0]
      if Process.returncode <> 0:
        sys.exit(Process.returncode)
        
      #
      # Write output file that contains hash GUID, Public Key, Signature, and Input data
      #    
      args.OutputFile = open(args.OutputFileName, 'wb')
      args.OutputFile.write(EFI_HASH_ALGORITHM_SHA256_GUID.get_bytes_le())
      args.OutputFile.write(PublicKey)
      args.OutputFile.write(Signature)
      args.OutputFile.write(args.InputFileBuffer)
      args.OutputFile.close()
  
    if args.Decode:
      #
      # Parse Hash Type, Public Key, and Signature from the section header
      #
      Header = EFI_CERT_BLOCK_RSA_2048_SHA256._make(EFI_CERT_BLOCK_RSA_2048_SHA256_STRUCT.unpack_from(args.InputFileBuffer))
      args.InputFileBuffer = args.InputFileBuffer[EFI_CERT_BLOCK_RSA_2048_SHA256_STRUCT.size:]
      
      #
      # Verify that the Hash Type matches the expected SHA256 type
      #
      if uuid.UUID(bytes_le = Header.HashType) <> EFI_HASH_ALGORITHM_SHA256_GUID:
        print 'ERROR: unsupport hash GUID'
        sys.exit(1)
  
      #
      # Verify the public key
      #
      if Header.PublicKey <> PublicKey:
        print 'ERROR: Public key in input file does not match public key from private key file'
        sys.exit(1)
  
      #
      # Write Signature to output file
      #
      open(args.OutputFileName, 'wb').write(Header.Signature)
        
      #
      # Verify signature
      #    
      Process = subprocess.Popen('%s sha256 -prverify "%s" -signature %s' % (OpenSslCommand, args.PrivateKeyFileName, args.OutputFileName), stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
      Process.communicate(args.InputFileBuffer)
      if Process.returncode <> 0:
        print 'ERROR: Verification failed'
        os.remove (args.OutputFileName)
        sys.exit(Process.returncode)
  
      #
      # Save output file contents from input file 
      #    
      open(args.OutputFileName, 'wb').write(args.InputFileBuffer)
  