[OE-core] [meta-oe,v2] kernel-fitimage: introduce FIT_HASH_ALG

[Alex Kiernan]

On Wed, Jun 19, 2019 at 9:48 AM Luca Boccassi <luca.boccassi at gmail.com> wrote:
>
> On Tue, 2019-06-18 at 17:11 +0100, Richard Purdie wrote:
> > On Tue, 2019-06-18 at 08:53 -0700, Khem Raj wrote:
> > > On Tue, Jun 18, 2019 at 1:26 AM Luca Boccassi <
> > > luca.boccassi at gmail.com
> > > > wrote:
> > > > On Thu, 2017-11-02 at 16:48 +0100, Ayoub Zaki wrote:
> > > > > sanitize fitImage hash algorithm selection with FIT_HASH_ALG
> > > > > switch default hash algorithm from sha1 to sha256
> > > > >
> > > > > Signed-off-by: Ayoub Zaki <
> > > > > ayoub.zaki at embexus.com
> > > > >
> > > > > Acked-by: Denys Dmytriyenko <
> > > > > denys at ti.com
> > > > >
> > > > > ---
> > > > >  meta/classes/kernel-fitimage.bbclass | 13 ++++++++-----
> > > > >  1 file changed, 8 insertions(+), 5 deletions(-)
> > > > >
> > > > > diff --git a/meta/classes/kernel-fitimage.bbclass
> > > > > b/meta/classes/kernel-fitimage.bbclass
> > > > > index 179185b..3cc3a33 100644
> > > > > --- a/meta/classes/kernel-fitimage.bbclass
> > > > > +++ b/meta/classes/kernel-fitimage.bbclass
> > > > > @@ -36,6 +36,9 @@ python __anonymous () {
> > > > >  # Options for the device tree compiler passed to mkimage '-D'
> > > > > feature:
> > > > >  UBOOT_MKIMAGE_DTCOPTS ??= ""
> > > > >
> > > > > +# fitImage Hash Algo
> > > > > +FIT_HASH_ALG ?= "sha256"

Should this be ??=

> > > > > +
> > > > >  #
> > > > >  # Emit the fitImage ITS header
> > > > >  #
> > > > > @@ -95,7 +98,7 @@ EOF
> > > > >  # $4 ... Compression type
> > > > >  fitimage_emit_section_kernel() {
> > > > >
> > > > > -     kernel_csum="sha1"
> > > > > +     kernel_csum="${FIT_HASH_ALG}"
> > > > >
> > > > >       ENTRYPOINT=${UBOOT_ENTRYPOINT}
> > > > >       if [ -n "${UBOOT_ENTRYSYMBOL}" ]; then
> > > > > @@ -128,7 +131,7 @@ EOF
> > > > >  # $3 ... Path to DTB image
> > > > >  fitimage_emit_section_dtb() {
> > > > >
> > > > > -     dtb_csum="sha1"
> > > > > +     dtb_csum="${FIT_HASH_ALG}"
> > > > >
> > > > >       cat << EOF >> ${1}
> > > > >                  fdt@${2} {
> > > > > @@ -152,7 +155,7 @@ EOF
> > > > >  # $3 ... Path to setup image
> > > > >  fitimage_emit_section_setup() {
> > > > >
> > > > > -     setup_csum="sha1"
> > > > > +     setup_csum="${FIT_HASH_ALG}"
> > > > >
> > > > >       cat << EOF >> ${1}
> > > > >                  setup@${2} {
> > > > > @@ -179,7 +182,7 @@ EOF
> > > > >  # $3 ... Path to ramdisk image
> > > > >  fitimage_emit_section_ramdisk() {
> > > > >
> > > > > -     ramdisk_csum="sha1"
> > > > > +     ramdisk_csum="${FIT_HASH_ALG}"
> > > > >       ramdisk_ctype="none"
> > > > >       ramdisk_loadline=""
> > > > >       ramdisk_entryline=""
> > > > > @@ -237,7 +240,7 @@ EOF
> > > > >  # $6 ... default flag
> > > > >  fitimage_emit_section_config() {
> > > > >
> > > > > -     conf_csum="sha1"
> > > > > +     conf_csum="${FIT_HASH_ALG}"
> > > > >       if [ -n "${UBOOT_SIGN_ENABLE}" ] ; then
> > > > >               conf_sign_keyname="${UBOOT_SIGN_KEYNAME}"
> > > > >       fi
> > > >
> > > > Hi,
> > > >
> > > > Any update on this patch? It was acked almost 2 years ago.
> > > >
> > > > It would be great to have a way to change the hashsum algorithm
> > > > when
> > > > building signed images.
> > > >
> > >
> > > I agree, but it would be good to resend this patch on top of
> > > current
> > > master
> >
> > I managed to apply it to master so its in testing now.
> >
> > My concerns about the lack of tests for this class are the main
> > reason
> > patches here get held up.
> >
> > Cheers,
> >
> > Richard
>
> Thanks Richard - in case it helps, we've been using this patch for a
> few months at $work (on top of sumo) and it seems to work fine.
>

I expect that's true for everyone touching stuff in this class - it
works fine for them... the problem is everyone else, since it's
terribly fragile and has no tests.

I'd not be at all surprised if changing the default from sha1 to
sha256 doesn't break someone.

-- 
Alex Kiernan