[util] Improve processing of ROM images in Option::ROM

The Option::ROM module now compares the Code Type in the PCIR header
to 0x00 (PC-AT) in order to check the presence of other header types
(PnP, UNDI, iPXE, etc).  The validity of these headers are checked not
only by offset, but by range and signature checks also.  The image
checksum and initial size also depends on Code Type.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/src/util/disrom.pl b/src/util/disrom.pl
index 920a86b2..71eee590 100755
--- a/src/util/disrom.pl
+++ b/src/util/disrom.pl
@@ -28,8 +28,9 @@ my $romfile = shift || "-";
 my $rom = new Option::ROM;
 $rom->load ( $romfile );
 
-do {
+my $index = 0;
 
+do {
   die "Not an option ROM image\n"
       unless $rom->{signature} == ROM_SIGNATURE;
 
@@ -38,15 +39,16 @@ do {
   die "ROM image truncated (is $filelength, should be $romlength)\n"
       if $filelength < $romlength;
 
+  printf "Index: %d, offset: 0x%08x\n\n", $index++, $rom->file_offset;
   printf "ROM header:\n\n";
   printf "  %-16s 0x%02x (%d)\n", "Length:",
 	 $rom->{length}, ( $rom->{length} * 512 );
   printf "  %-16s 0x%02x (%s0x%02x)\n", "Checksum:", $rom->{checksum},
-	 ( ( $rom->checksum == 0 ) ? "" : "INCORRECT: " ), $rom->checksum;
-  printf "  %-16s 0x%04x\n", "Init:", $rom->{init};
-  printf "  %-16s 0x%04x\n", "UNDI header:", $rom->{undi_header};
+	 ( ( $rom->checksum () == 0 ) ? "" : "INCORRECT: " ), $rom->checksum () if ( exists $rom->{checksum} );
+  printf "  %-16s 0x%04x\n", "Init:", $rom->{init} if ( defined $rom->{init} );
+  printf "  %-16s 0x%04x\n", "UNDI header:", $rom->{undi_header} if ( exists $rom->{undi_header} );
   printf "  %-16s 0x%04x\n", "PCI header:", $rom->{pci_header};
-  printf "  %-16s 0x%04x\n", "PnP header:", $rom->{pnp_header};
+  printf "  %-16s 0x%04x\n", "PnP header:", $rom->{pnp_header} if ( exists $rom->{pnp_header} );
   printf "\n";
 
   my $pci = $rom->pci_header();