From 858fffb5cefc8ed4b38996b5ced9d0c1f075e368 Mon Sep 17 00:00:00 2001
From: vbendeb <vbendeb@chromium.org>
Date: Wed, 6 Oct 2010 09:51:44 -0700
Subject: [PATCH] Allow --repack option to change kernel version number.

RFro TPM rollback testing we need to be able to change kernel
version number. This Cl adds this ability to the
vbutil_kernel utility.

Change-Id: I156df9b0d3467043c20a43e1c75e6d0222704f3a

BUG=chromium-os:1976
TEST=manual

1. On a target running off /dev/sda3 (as reported by
'rootdev -s') execute `/usr/bin/dev_debug_vboot' and take
note of the kernel version number in the output section
starting with 'TEST: verify HD kernel A with firmware A key',
under 'Preamble' it should read
'Kernel version:      1'

2. copy the kernel into a file:
dd if=/dev/sda2 of=/tmp/kernel

3.on the desktop (this step requires ssh setup to use the
correct keys to reach the target):

scp tests/devkeys/kernel_data_key.vbprivk <target>:/tmp

3. Modify kernel version
vbutil_kernel --repack /tmp/repacked.k --version 2 --signprivate /tmp/kernel_data_key.vbprivk  --oldblob  /tmp/kernel

4. Install the updated kernel
dd if=/tmp/repacked.k of=/dev/sda2

5. restart the system

6. Observe that it came up using /dev/sda3 as the root
file system

7. run /usr/bin/dev_debug_vboot and observe that the kernel
version is no set to 2

Review URL: http://codereview.chromium.org/3520019
---
 utility/vbutil_kernel.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/utility/vbutil_kernel.c b/utility/vbutil_kernel.c
index acf156f704..391f5ad284 100644
--- a/utility/vbutil_kernel.c
+++ b/utility/vbutil_kernel.c
@@ -91,13 +91,14 @@ static int PrintHelp(char *progname) {
           "\nOR\n\n"
           "Usage:  %s --repack <file> [PARAMETERS]\n"
           "\n"
-          "  Required parameters (of --keyblock and --config at least "
-          "one is required):\n"
+          "  Required parameters (of --keyblock, --config, and --version \n"
+          "    at least one is required):\n"
           "    --keyblock <file>         Key block in .keyblock format\n"
           "    --signprivate <file>"
           "      Private key to sign kernel data, in .vbprivk format\n"
           "    --oldblob <file>          Previously packed kernel blob\n"
           "    --config <file>           New command line file\n"
+          "    --version <number>        Kernel version\n"
           "\n"
           "  Optional:\n"
           "    --pad <number>            Verification padding size in bytes\n"
@@ -846,9 +847,10 @@ int main(int argc, char* argv[]) {
       return r;
 
     case OPT_MODE_REPACK:
-      if (!config_file && !key_block_file) {
+      if (!config_file && !key_block_file && !version) {
         fprintf(stderr,
-                "You must supply at least one of --config and --keyblock\n");
+                "You must supply at least one of "
+                "--config, --keyblock or --version\n");
         return 1;
       }
 
@@ -857,6 +859,9 @@ int main(int argc, char* argv[]) {
         return 1;
       r = ReplaceConfig(bp, config_file);
       if (!r) {
+        if (version) {
+          bp->kernel_version = version;
+        }
         r = Pack(filename, key_block_file, signprivate, bp, pad, vblockonly);
       }
       FreeBlob(bp);