Add a --vblock option to firmware_utility to only output the verification block.

src/platform/vboot_reference/utility/firmware_utility.cc

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Utility for manipulating verified boot firmware images.
 //
 
 #include "firmware_utility.h"
 
 #include <errno.h>
@@ skipping 44 matching lines @@
       "For \"--generate\", required OPTIONS are:\n"
       "--root_key <privkeyfile>\tPrivate root key file\n"
       "--firmware_sign_key <privkeyfile>\tPrivate signing key file\n"
       "--firmware_sign_key_pub <pubkeyfile>\tPre-processed public signing"
       " key\n"
       "--firmware_sign_algorithm <algoid>\tSigning algorithm to use\n"
       "--firmware_key_version <version#>\tSigning Key Version#\n"
       "--firmware_version <version#>\tFirmware Version#\n"
       "--in <infile>\t\t\tFirmware Image to sign\n"
       "--out <outfile>\t\t\tOutput file for verified boot firmware image\n\n"
+      "Optional:\n"
+      " --vblock\t\t\tJust output the verification block\n\n"
       "<algoid> (for --sign-algorithm) is one of the following:\n";
+
   for (int i = 0; i < kNumAlgorithms; i++) {
     cerr << i << " for " << algo_strings[i] << "\n";
   }
   cerr << "\n\n";
 }
 
 bool FirmwareUtility::ParseCmdLineOptions(int argc, char* argv[]) {
   int option_index;
   static struct option long_options[] = {
     {"root_key", 1, 0, 0},
     {"root_key_pub", 1, 0, 0},
     {"firmware_sign_key", 1, 0, 0},
     {"firmware_sign_key_pub", 1, 0, 0},
     {"firmware_sign_algorithm", 1, 0, 0},
     {"firmware_key_version", 1, 0, 0},
     {"firmware_version", 1, 0, 0},
     {"in", 1, 0, 0},
     {"out", 1, 0, 0},
     {"generate", 0, 0, 0},
     {"verify", 0, 0, 0},
     {"describe", 0, 0, 0},
+    {"vblock", 0, 0, 0},
     {NULL, 0, 0, 0}
   };
   while (1) {
     int i = getopt_long(argc, argv, "", long_options, &option_index);
     if (-1 == i)  // Done with option processing.
       break;
     if ('?' == i)  // Invalid option found.
       return false;
 
     if (0 == i) {
@@ skipping 39 matching lines @@
           break;
         case 9:  // generate
           is_generate_ = true;
           break;
         case 10:  // verify
           is_verify_ = true;
           break;
         case 11:  // describe
           is_describe_ = true;
           break;
+        case 12: // vblock
+          is_only_vblock_ = true;
+          break;
       }
     }
   }
   return CheckOptions();
 }
 
 
 void FirmwareUtility::OutputSignedImage(void) {
   if (image_) {
-    if (!WriteFirmwareImage(out_file_.c_str(), image_)) {
+    if (!WriteFirmwareImage(out_file_.c_str(), image_, is_only_vblock_)) {
         cerr << "Couldn't write verified boot image to file "
                   << out_file_ <<".\n";
     }
   }
 }
 
 void FirmwareUtility::DescribeSignedImage(void) {
   image_ = ReadFirmwareImage(in_file_.c_str());
   if (!image_) {
     cerr << "Couldn't read firmware image or malformed image.\n";
@@ skipping 138 matching lines @@
   }
   if (fu.is_verify()) {
     cerr << "Verification ";
     if (fu.VerifySignedImage())
       cerr << "SUCCESS.\n";
     else
       cerr << "FAILURE.\n";
   }
   return 0;
 }