Add --describe flag to {firmware|kernel}_utility.

src/platform/vboot_reference/utils/kernel_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 kernel images.
 //
 
 #include "kernel_utility.h"
 
 #include <errno.h>
@@ skipping 20 matching lines @@
 namespace vboot_reference {
 
 KernelUtility::KernelUtility(): image_(NULL),
                                 firmware_key_pub_(NULL),
                                 header_version_(1),
                                 firmware_sign_algorithm_(-1),
                                 kernel_sign_algorithm_(-1),
                                 kernel_key_version_(-1),
                                 kernel_version_(-1),
                                 is_generate_(false),
-                                is_verify_(false) {
+                                is_verify_(false),
+                                is_describe_(false){
   // Populate kernel config options with defaults.
   options_.version[0] = 1;
   options_.version[1] = 0;
   options_.kernel_len = 0;
   options_.kernel_load_addr = 0;
   options_.kernel_entry_addr = 0;
 }
 
 KernelUtility::~KernelUtility() {
   RSAPublicKeyFree(firmware_key_pub_);
   KernelImageFree(image_);
 }
 
 void KernelUtility::PrintUsage(void) {
   cerr <<
-      "Utility to generate/verify a verified boot kernel image\n\n"
-      "Usage: kernel_utility <--generate|--verify> [OPTIONS]\n\n"
+      "Utility to generate/verify/describe a verified boot kernel image\n\n"
+      "Usage: kernel_utility <--generate|--verify|--describe> [OPTIONS]\n\n"
       "For \"--verify\",  required OPTIONS are:\n"
       "--in <infile>\t\t\tVerified boot kernel image to verify.\n"
       "--firmware_key_pub <pubkeyfile>\tPre-processed public firmware key "
       "to use for verification.\n\n"
       "For \"--generate\", required OPTIONS are:\n"
       "--firmware_key <privkeyfile>\tPrivate firmware signing key file\n"
       "--kernel_key <privkeyfile>\tPrivate kernel signing key file\n"
       "--kernel_key_pub <pubkeyfile>\tPre-processed public kernel signing"
       " key\n"
       "--firmware_sign_algorithm <algoid>\tSigning algorithm used by "
@@ skipping 25 matching lines @@
     {"kernel_sign_algorithm", 1, 0, 0},
     {"kernel_key_version", 1, 0, 0},
     {"kernel_version", 1, 0, 0},
     {"in", 1, 0, 0},
     {"out", 1, 0, 0},
     {"generate", 0, 0, 0},
     {"verify", 0, 0, 0},
     {"config_version", 1, 0, 0},
     {"kernel_load_addr", 1, 0, 0},
     {"kernel_entry_addr", 1, 0, 0},
+    {"describe", 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 59 matching lines @@
           errno = 0;
           options_.kernel_load_addr =
               strtol(optarg, reinterpret_cast<char**>(NULL), 10);
           if (errno)
             return false;
           break;
         case 14:  // kernel_entry_addr
           errno = 0;
           options_.kernel_entry_addr =
               strtol(optarg, reinterpret_cast<char**>(NULL), 10);
-
           if (errno)
             return false;
           break;
+        case 15:  // describe
+          is_describe_ = true;
+          break;
       }
     }
   }
   return CheckOptions();
 }
 
 void KernelUtility::OutputSignedImage(void) {
   if (image_) {
     if (!WriteKernelImage(out_file_.c_str(), image_)) {
       cerr << "Couldn't write verified boot kernel image to file "
            << out_file_ <<".\n";
     }
   }
 }
 
+void KernelUtility::DescribeSignedImage(void) {
+  image_ = ReadKernelImage(in_file_.c_str());
+  if (!image_) {
+    cerr << "Couldn't read kernel image or malformed image.\n";
+    return;
+  }
+  PrintKernelImage(image_);
+}
+
 bool KernelUtility::GenerateSignedImage(void) {
   uint64_t kernel_key_pub_len;
-  uint8_t* header_checksum;
-  DigestContext ctx;
   image_ = KernelImageNew();
 
   Memcpy(image_->magic, KERNEL_MAGIC, KERNEL_MAGIC_SIZE);
 
   // TODO(gauravsh): make this a command line option.
   image_->header_version = 1;
   image_->firmware_sign_algorithm = (uint16_t) firmware_sign_algorithm_;
   // Copy pre-processed public signing key.
   image_->kernel_sign_algorithm = (uint16_t) kernel_sign_algorithm_;
   image_->kernel_sign_key = BufferFromFile(kernel_key_pub_file_.c_str(),
                                            &kernel_key_pub_len);
   if (!image_->kernel_sign_key)
     return false;
   image_->kernel_key_version = kernel_key_version_;
 
   // Update header length.
   image_->header_len = GetKernelHeaderLen(image_);
 
   // Calculate header checksum.
-  DigestInit(&ctx, SHA512_DIGEST_ALGORITHM);
-  DigestUpdate(&ctx, reinterpret_cast<uint8_t*>(&image_->header_version),
-               sizeof(image_->header_version));
-  DigestUpdate(&ctx, reinterpret_cast<uint8_t*>(&image_->header_len),
-               sizeof(image_->header_len));
-  DigestUpdate(&ctx,
-               reinterpret_cast<uint8_t*>(&image_->firmware_sign_algorithm),
-               sizeof(image_->firmware_sign_algorithm));
-  DigestUpdate(&ctx,
-               reinterpret_cast<uint8_t*>(&image_->kernel_sign_algorithm),
-               sizeof(image_->kernel_sign_algorithm));
-  DigestUpdate(&ctx, reinterpret_cast<uint8_t*>(&image_->kernel_key_version),
-               sizeof(image_->kernel_key_version));
-  DigestUpdate(&ctx, image_->kernel_sign_key,
-               RSAProcessedKeySize(image_->kernel_sign_algorithm));
-  header_checksum = DigestFinal(&ctx);
-  Memcpy(image_->header_checksum, header_checksum, SHA512_DIGEST_SIZE);
-  Free(header_checksum);
+  CalculateKernelHeaderChecksum(image_, image_->header_checksum);
 
   image_->kernel_version = kernel_version_;
   image_->options.version[0] = options_.version[0];
   image_->options.version[1] = options_.version[1];
+  // TODO(gauravsh): Add a command line option for this.
+  Memset(image_->options.cmd_line, 0, sizeof(image_->options.cmd_line));
   image_->options.kernel_load_addr = options_.kernel_load_addr;
   image_->options.kernel_entry_addr = options_.kernel_entry_addr;
   image_->kernel_data = BufferFromFile(in_file_.c_str(),
                                        &image_->options.kernel_len);
   if (!image_)
     return false;
   // Generate and add the signatures.
   if (!AddKernelKeySignature(image_, firmware_key_file_.c_str())) {
     cerr << "Couldn't write key signature to verified boot kernel image.\n";
     return false;
@@ skipping 20 matching lines @@
     cerr << "Couldn't read kernel image or malformed image.\n";
     return false;
   }
   if (!(error = VerifyKernelImage(firmware_key_pub_, image_, 0)))
     return true;
   cerr << VerifyKernelErrorString(error) << "\n";
   return false;
 }
 
 bool KernelUtility::CheckOptions(void) {
-  if (is_generate_ == is_verify_) {
-    cerr << "One of --generate or --verify must be specified.\n";
+  // Ensure that only one of --{describe|generate|verify} is set.
+  if (!((is_describe_ && !is_generate_ && !is_verify_) ||
+        (!is_describe_ && is_generate_ && !is_verify_) ||
+        (!is_describe_ && !is_generate_ && is_verify_))) {
+    cerr << "One (and only one) of --describe, --generate or --verify "
+         << "must be specified.\n";
     return false;
   }
   // Common required options.
   if (in_file_.empty()) {
     cerr << "No input file specified.\n";
     return false;
   }
   // Required options for --verify.
   if (is_verify_ && firmware_key_pub_file_.empty()) {
     cerr << "No pre-processed public firmware key file specified.\n";
@@ skipping 35 matching lines @@
       cerr <<"No output file specified.\n";
       return false;
     }
   }
   return true;
 }
 
 }  // namespace vboot_reference
 
 int main(int argc, char* argv[]) {
-  vboot_reference::KernelUtility fu;
-  if (!fu.ParseCmdLineOptions(argc, argv)) {
-    fu.PrintUsage();
+  vboot_reference::KernelUtility ku;
+  if (!ku.ParseCmdLineOptions(argc, argv)) {
+    ku.PrintUsage();
     return -1;
   }
-  if (fu.is_generate()) {
-    if (!fu.GenerateSignedImage())
+  if (ku.is_describe()) {
+    ku.DescribeSignedImage();
+  }
+  else if (ku.is_generate()) {
+    if (!ku.GenerateSignedImage())
       return -1;
-    fu.OutputSignedImage();
+    ku.OutputSignedImage();
   }
-  if (fu.is_verify()) {
+  else if (ku.is_verify()) {
     cerr << "Verification ";
-    if (fu.VerifySignedImage())
+    if (ku.VerifySignedImage())
       cerr << "SUCCESS.\n";
     else
       cerr << "FAILURE.\n";
   }
   return 0;
 }