[PATCH v2 4/6] net: lwip: add support for built-in root certificates

[Ilias Apalodimas]

On Mon, 10 Mar 2025 at 14:13, Jerome Forissier
<jerome.forissier at linaro.org> wrote:
>
>
>
> On 3/10/25 12:52, Ilias Apalodimas wrote:
> > Hi Jerome,
> >
> > [...]
> >
> >
> >>>>
> >>>> +#if CONFIG_IS_ENABLED(WGET_BUILTIN_CACERT)
> >>>> +       cacert_initialized = true;
> >>>> +#endif
> >>>>         return CMD_RET_SUCCESS;
> >>>>  }
> >>>> +
> >>>> +#if CONFIG_IS_ENABLED(WGET_BUILTIN_CACERT)
> >>>> +static int set_cacert_builtin(void)
> >>>> +{
> >>>> +       return _set_cacert(builtin_cacert, builtin_cacert_size);
> >>>> +}
> >>>>  #endif
> >>>>
> >>>> +#if CONFIG_IS_ENABLED(WGET_CACERT)
> >>>> +static int set_cacert(char * const saddr, char * const ssz)
> >>>> +{
> >>>> +       ulong addr, sz;
> >>>> +
> >>>> +       addr = hextoul(saddr, NULL);
> >>>> +       sz = hextoul(ssz, NULL);
> >>>> +
> >>>> +       return _set_cacert((void *)addr, sz);
> >>>> +}
> >>>> +#endif
> >>>> +#endif  /* CONFIG_WGET_CACERT || CONFIG_WGET_BUILTIN_CACERT */
> >>>> +
> >>>>  static int wget_loop(struct udevice *udev, ulong dst_addr, char *uri)
> >>>>  {
> >>>>  #if CONFIG_IS_ENABLED(WGET_HTTPS)
> >>>> @@ -373,8 +401,15 @@ static int wget_loop(struct udevice *udev, ulong dst_addr, char *uri)
> >>>>         memset(&conn, 0, sizeof(conn));
> >>>>  #if CONFIG_IS_ENABLED(WGET_HTTPS)
> >>>>         if (is_https) {
> >>>> -               char *ca = cacert;
> >>>> -               size_t ca_sz = cacert_size;
> >>>> +               char *ca;
> >>>> +               size_t ca_sz;
> >>>> +
> >>>> +#if CONFIG_IS_ENABLED(WGET_BUILTIN_CACERT)
> >>>> +               if (!cacert_initialized)
> >>>> +                       set_cacert_builtin();
> >>>> +#endif
> >>>
> >>> The code and the rest of the patch seems fine, but the builtin vs
> >>> downloaded cert is a bit confusing here.
> >>> Since the built-in cert always gets initialized in the wget loop it
> >>> would overwrite any certificates that are downloaded in memory?
> >>
> >> The built-in certs are enabled only when cacert_initialized is false.
> >> set_cacert_builtin() will set it to true (via _set_cacert()), so it will
> >> happen only once. Note also that any successful "wget cacert" command
> >> will also do the same. So effectively these two lines enable the
> >> built-in certificates by default, that's all they do.
> >
> > Ok, so if you download a cert in memory and have u-boot with a builtin
> > certificate, then the memory one will be overwritten in the first run.
>
> No, because the downloaded cert must have be made active via "wget cacert
> <addr> <size>", which will set cacert_initialized to true, and thus the
> built-in certs won't overwrite them. Or did I miss something?

Nop I did, when reading the patch. But should the command that clears
the downloaded cert set cacert_initialized; to false now?

Thanks
/Ilias
>
> Cheers,
> --
> Jerome
>
> > This is not easy to solve, I was trying to think of ways to make the
> > functionality clearer to users.
> >
> > Cheers
> > /Ilias
> >>
> >> Cheers,
> >> --
> >> Jerome
> >>
> >>>
> >>> [...]
> >>>
> >>> Cheers
> >>> /Ilias