[pacman-dev] [PATCH 3/3] pacman: add file checksum validation against mtree

[Emil Velikov]

On Tue, 29 Dec 2020 at 03:02, Allan McRae <allan at archlinux.org> wrote:
>
> On 24/12/20 8:43 am, Emil Velikov wrote:
> > With libarchive v3.5.0 we have API to fetch the digest from the mtree.
> > Use that to validate if the installed files are modified or not.
> >
> > As always, a modified backup file will trigger a warning but will not
> > result in an actual failure.
> >
> > TODO: localization... no idea how that is even done :-)
>
> Adding the _() around the strings is all that needed done.
>
Perfect thanks.

> > NOTE: indentation is likely all over the place - first time I see ts=2
>
> For line wraps, we generally just use two indents, so really does not
> matter what the tab system is.
>
Was mostly curious about wrapping of multiline function calls. It
seems that "use an extra tab" is common practise - worth adding an
example in the Coding style section in HACKING?

> > Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
> > ---
> >  src/pacman/check.c | 66 +++++++++++++++++++++++++++++++++++++++++-----
> >  1 file changed, 59 insertions(+), 7 deletions(-)
> >
> > diff --git a/src/pacman/check.c b/src/pacman/check.c
> > index 02217d0f..083c547d 100644
> > --- a/src/pacman/check.c
> > +++ b/src/pacman/check.c
> > @@ -176,19 +176,70 @@ static int check_file_size(const char *pkgname, const char *filepath,
> >       return 0;
> >  }
> >
> > -/* placeholders - libarchive currently does not read checksums from mtree files
> > -static int check_file_md5sum(const char *pkgname, const char *filepath,
> > -             struct stat *st, struct archive_entry *entry, int backup)
> > +#if ARCHIVE_VERSION_NUMBER >= 3005000
>
> This does not need wrapped in #if.  There is nothing libarchive specific
> in this function.
>
Without this the compiler will flag it as -Wunused-function. I could
silence that by annotating the function as __attribute__((used)).
Would you prefer that or you have something else in mind?

> > +static int check_file_cksum(const char *pkgname, const char *filepath,
> > +             int backup, const char *cksum_name, const char *cksum_calc, const char *cksum_mtree)
> >  {
> > +     if(!cksum_calc || !cksum_mtree) {
>
> Only one of these failures matches the error message.   Split into
> "checkusm information not available" and "failed to calculate checksum"
>
Ack will do.

Thanks
Emil