HP workaround as default without define

README.md

@@ -69,10 +69,7 @@ In order to use the TCG-enhanced TrustedGRUB2, you need a computer which has TCG
 
 ### 1.5 Known Bugs / Limitations
 
-* On some HP notebooks and workstations, TrustedGRUB2 is not able to do the kernel measurements due to a buggy BIOS. This means PCR 8,9 can contain bogus values. This seems to be especially the case if the core.img is bigger than 64KB. 
-* For this We probably have found a workaround: HP desktop/laptop BIOS seems to be unable to handle blocks ending on 512 byte boundaries when measuring data. So we increase the number of bytes to read by 1 and also the number of sectors to read, which ensures that all bytes of core.img are read. For this to work correctly the loaded core.img must be padded with zeroes or some other fixed value. grub_mkimage has already been adjusted to pad core.img with zeroes to a 512 byte alignment. The missing zero byte has to be added by yourself. The workaround can be found in diskboot.S . Further uncomment `/* #define TGRUB_HP_WORKAROUND */` in tpm.h
-
-If you find any bugs, create an issue or send a mail to trustedgrub@sirrix.com
+If you find any bugs, create an issue on github
 
 ### 1.6 Configuring TrustedGRUB2 before installation
 

grub-core/boot/i386/pc/diskboot.S

@@ -69,20 +69,19 @@ _start:
 	 * will ever be a core.img larger than that. ;-) */
 	shll	$9, %eax
 
-#ifdef TGRUB_HP_WORKAROUND
 	/* HP workaround
 	 * This is a workaround for HP desktop/laptop BIOS which seem to be
 	 * unable to handle blocks ending on 512 byte boundaries when measuring
 	 * data. So we increase the number of bytes to read by 1 and also the
 	 * number of sectors to read, which ensures that all bytes of core.img
 	 * are read. For this to work correctly the loaded core.img must be
 	 * padded with zeroes or some other fixed value:
-	 * 1) pad core.img with zeroes to 512 byte blocks. Already done by grub_mkimage adjustment
-	 * 2) append 1 extra zero byte to core.img. Has to be done by yourself.
+	 * 1) pad core.img with zeroes to 512 byte blocks.
+	 * 2) append 1 extra zero byte to core.img.
+	 * Step 1 and 2 are already implemented in grub_mkimage
 	 * */
 	inc	%eax   /* add 1 to number_of_bytes_to_measure */
 	incw	8(%di) /* make code below read 1 more sector than specified */
-#endif
 
 	/* write result to number_of_bytes_to_measure var */
 	movl	%eax, number_of_bytes_to_measure

include/grub/i386/pc/tpm.h

@@ -6,8 +6,6 @@
 
 /* #define TGRUB_DEBUG */
 
-/* #define TGRUB_HP_WORKAROUND */
-
 #ifdef TGRUB_DEBUG
 	#define DEBUG_PRINT( x ) grub_printf x
 #else

util/mkimage.c

@@ -1402,9 +1402,10 @@ grub_install_generate_image (const char *dir, const char *prefix,
 	free (boot_path);
 
 /* BEGIN TCG EXTENSION */
-
-	/* To simplify measurement the core.img should be 512 byte aligned  */
+	/* HP workaround */
+	/* core.img size has to be core_size % 512 != 0  */
         size_t newCoreImgSize = ALIGN_UP (core_size, 512);
+	newCoreImgSize++;
 
 	void* newCoreImg = xmalloc (newCoreImgSize);
         memset (newCoreImg, 0, newCoreImgSize);