[U-Boot] [PATCH] rpi3: Enable verified boot from FIT image

[Jun Nie]

Matthias Brugger <mbrugger at suse.com> 于2019年7月31日周三 下午4:05写道：
>
>
>
> On 11/07/2019 05:55, Jun Nie wrote:
> > Enable verified boot from FIT image with select configs
> > and specify boot script image node in FIT image, the FIT
> > image is verified before it is run.
> >
> > Code that reusing dtb in firmware is disabled, so that
> > the dtb with pubic key packed in u-boot.bin can be used
> > to verify the signature of next stage FIT image.
> >
> > Signed-off-by: Jun Nie <jun.nie at linaro.org>
> > ---
> >  board/raspberrypi/rpi/rpi.c |  6 ++++++
> >  include/configs/rpi.h       | 15 ++++++++++++++-
> >  2 files changed, 20 insertions(+), 1 deletion(-)
> >
> > diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c
> > index 617c892..950ee84 100644
> > --- a/board/raspberrypi/rpi/rpi.c
> > +++ b/board/raspberrypi/rpi/rpi.c
> > @@ -297,6 +297,7 @@ static void set_fdtfile(void)
> >       env_set("fdtfile", fdtfile);
> >  }
> >
> > +#ifndef CONFIG_FIT_SIGNATURE
> >  /*
> >   * If the firmware provided a valid FDT at boot time, let's expose it in
> >   * ${fdt_addr} so it may be passed unmodified to the kernel.
> > @@ -311,6 +312,7 @@ static void set_fdt_addr(void)
> >
> >       env_set_hex("fdt_addr", fw_dtb_pointer);
> >  }
> > +#endif
> >
> >  /*
> >   * Prevent relocation from stomping on a firmware provided FDT blob.
> > @@ -393,7 +395,9 @@ static void set_serial_number(void)
> >
> >  int misc_init_r(void)
> >  {
> > +#ifndef CONFIG_FIT_SIGNATURE
> >       set_fdt_addr();
> > +#endif
> >       set_fdtfile();
> >       set_usbethaddr();
> >  #ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
> > @@ -470,6 +474,7 @@ int board_init(void)
> >       return bcm2835_power_on_module(BCM2835_MBOX_POWER_DEVID_USB_HCD);
> >  }
> >
> > +#ifndef CONFIG_FIT_SIGNATURE
> >  /*
> >   * If the firmware passed a device tree use it for U-Boot.
> >   */
> > @@ -479,6 +484,7 @@ void *board_fdt_blob_setup(void)
> >               return NULL;
> >       return (void *)fw_dtb_pointer;
> >  }
> > +#endif
>
> Just to get this clear we need this because we want to pass the device tree via
> OF_SEPARATE, correct?

You are right.  U-boot need to read he signature from dtb.

>
> >
> >  int ft_board_setup(void *blob, bd_t *bd)
> >  {
> > diff --git a/include/configs/rpi.h b/include/configs/rpi.h
> > index f76c7d1..ba91205 100644
> > --- a/include/configs/rpi.h
> > +++ b/include/configs/rpi.h
> > @@ -180,11 +180,24 @@
> >
> >  #include <config_distro_bootcmd.h>
> >
> > +#ifdef CONFIG_FIT_SIGNATURE
> > +#define FIT_BOOT_CMD                                                 \
> > +     "boot_a_script="                                                \
> > +             "load ${devtype} ${devnum}:${distro_bootpart} "         \
> > +                     "${scriptaddr} ${prefix}${script}; "            \
> > +             "iminfo ${scriptaddr};"                                 \
> > +             "if test $? -eq 1; then reset; fi;"                     \
> > +             "source ${scriptaddr}:bootscr\0"
> > +#else
> > +#define FIT_BOOT_CMD ""
> > +#endif
> > +
>
> Doesn't this overwrite the boot_a_script in distro_bootcmd?
>
> Would it make sense to add FIT booting to the distro boot command?
>
> Regards,
> Matthias

Yes, it overwrite the boot_a_script in distro_bootcmd. It is make
sense to add this to the distro boot command. I can send another patch
to move these lines to common code later.

>
> >  #define CONFIG_EXTRA_ENV_SETTINGS \
> >       "dhcpuboot=usb start; dhcp u-boot.uimg; bootm\0" \
> >       ENV_DEVICE_SETTINGS \
> >       ENV_MEM_LAYOUT_SETTINGS \
> > -     BOOTENV
> > +     BOOTENV \
> > +     FIT_BOOT_CMD
> >
> >
> >  #endif
> >