On Mon, Oct 19, 2020 at 06:09:55PM -0500, Glenn Washburn wrote:
> This should improve readability of code by providing clues as to what the
> value represents.
>
> Signed-off-by: Glenn Washburn <developm...@efficientek.com>
> ---
> grub-core/disk/cryptodisk.c | 12 +++++++-----
> include/grub/types.h | 3 +++
> 2 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/grub-core/disk/cryptodisk.c b/grub-core/disk/cryptodisk.c
> index 623f0f396..1a91c2d55 100644
> --- a/grub-core/disk/cryptodisk.c
> +++ b/grub-core/disk/cryptodisk.c
> @@ -297,19 +297,21 @@ grub_cryptodisk_endecrypt (struct grub_cryptodisk *dev,
> }
> break;
> case GRUB_CRYPTODISK_MODE_IV_BYTECOUNT64:
> - iv[1] = grub_cpu_to_le32 (sector >> (32 - log_sector_size));
> + /* The IV is the 64 bit byte offset of the sector. */
> + iv[1] = grub_cpu_to_le32 (sector >> (GRUB_TYPE_BIT(iv[0])
> + - log_sector_size));
> iv[0] = grub_cpu_to_le32 ((sector << log_sector_size)
> - & 0xFFFFFFFF);
> + & GRUB_TYPE_MAX(iv[0]));
> break;
> case GRUB_CRYPTODISK_MODE_IV_BENBI:
> {
> grub_uint64_t num = (sector << dev->benbi_log) + 1;
> - iv[sz - 2] = grub_cpu_to_be32 (num >> 32);
> - iv[sz - 1] = grub_cpu_to_be32 (num & 0xFFFFFFFF);
> + iv[sz - 2] = grub_cpu_to_be32 (num >> GRUB_TYPE_BIT(iv[0]));
> + iv[sz - 1] = grub_cpu_to_be32 (num & GRUB_TYPE_MAX(iv[0]));
> }
> break;
> case GRUB_CRYPTODISK_MODE_IV_ESSIV:
> - iv[0] = grub_cpu_to_le32 (sector & 0xFFFFFFFF);
> + iv[0] = grub_cpu_to_le32 (sector & GRUB_TYPE_MAX(iv[0]));
> err = grub_crypto_ecb_encrypt (dev->essiv_cipher, iv, iv,
> dev->cipher->cipher->blocksize);
> if (err)
> diff --git a/include/grub/types.h b/include/grub/types.h
> index 035a4b528..8b4267ebd 100644
> --- a/include/grub/types.h
> +++ b/include/grub/types.h
> @@ -319,4 +319,7 @@ static inline void grub_set_unaligned64 (void *ptr,
> grub_uint64_t val)
>
> #define GRUB_CHAR_BIT 8
>
> +#define GRUB_TYPE_BIT(type) (sizeof(type) * GRUB_CHAR_BIT)Hum. I'd rather name this `GRUB_TYPE_BITS`, as the current name implies that we only get a single bit. Other than that the change looks good to me and I agree that it helps readability. Patrick > +#define GRUB_TYPE_MAX(type) ((2 * ((1ULL << (GRUB_TYPE_BIT(type) - 1)) - 1)) > + 1) > + > #endif /* ! GRUB_TYPES_HEADER */ > -- > 2.27.0 >
signature.asc
Description: PGP signature
_______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
