On 08.11.21 16:28, Roman Kopytin wrote: > Having to use the -K option to mkimage to populate U-Boot's .dtb with the > public key while signing the kernel FIT image is often a little > awkward. In particular, when using a meta-build system such as > bitbake/Yocto, having the tasks of the kernel and U-Boot recipes > intertwined, modifying deployed artifacts and rebuilding U-Boot with > an updated .dtb is quite cumbersome. Also, in some scenarios one may > wish to build U-Boot complete with the public key(s) embedded in the > .dtb without the corresponding private keys being present on the same > build host. > > So this adds a simple tool that allows one to disentangle the kernel > and U-Boot builds, by simply copy-pasting just enough of the mkimage > code to allow one to add a public key to a .dtb. When using mkimage, > some of the information is taken from the .its used to build the > kernel (algorithm and key name), so that of course needs to be > supplied on the command line. > > Signed-off-by: Roman Kopytin <roman.kopy...@kaspersky.com> > Cc: Rasmus Villemoes <rasmus.villem...@prevas.dk> > --- > tools/.gitignore | 1 + > tools/Makefile | 3 ++ > tools/fdt_add_pubkey.c | 97 ++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 101 insertions(+) > create mode 100755 tools/fdt_add_pubkey.c > > diff --git a/tools/.gitignore b/tools/.gitignore > index a88453f64d..f312b760e4 100644 > --- a/tools/.gitignore > +++ b/tools/.gitignore > @@ -6,6 +6,7 @@ > /dumpimage > /easylogo/easylogo > /envcrc > +/fdt_add_pubkey > /fdtgrep > /file2include > /fit_check_sign > diff --git a/tools/Makefile b/tools/Makefile > index 4a86321f64..44f25dda18 100644 > --- a/tools/Makefile > +++ b/tools/Makefile > @@ -73,6 +73,7 @@ mkenvimage-objs := mkenvimage.o os_support.o lib/crc32.o > > hostprogs-y += dumpimage mkimage > hostprogs-$(CONFIG_TOOLS_LIBCRYPTO) += fit_info fit_check_sign > +hostprogs-$(CONFIG_TOOLS_LIBCRYPTO) += fdt_add_pubkey > > hostprogs-$(CONFIG_CMD_BOOTEFI_SELFTEST) += file2include > > @@ -153,6 +154,7 @@ dumpimage-objs := $(dumpimage-mkimage-objs) dumpimage.o > mkimage-objs := $(dumpimage-mkimage-objs) mkimage.o > fit_info-objs := $(dumpimage-mkimage-objs) fit_info.o > fit_check_sign-objs := $(dumpimage-mkimage-objs) fit_check_sign.o > +fdt_add_pubkey-objs := $(dumpimage-mkimage-objs) fdt_add_pubkey.o > file2include-objs := file2include.o > > ifneq ($(CONFIG_MX23)$(CONFIG_MX28)$(CONFIG_TOOLS_LIBCRYPTO),) > @@ -190,6 +192,7 @@ HOSTCFLAGS_fit_image.o += > -DMKIMAGE_DTC=\"$(CONFIG_MKIMAGE_DTC_PATH)\" > HOSTLDLIBS_dumpimage := $(HOSTLDLIBS_mkimage) > HOSTLDLIBS_fit_info := $(HOSTLDLIBS_mkimage) > HOSTLDLIBS_fit_check_sign := $(HOSTLDLIBS_mkimage) > +HOSTLDLIBS_fdt_add_pubkey := $(HOSTLDLIBS_mkimage) > > hostprogs-$(CONFIG_EXYNOS5250) += mkexynosspl > hostprogs-$(CONFIG_EXYNOS5420) += mkexynosspl > diff --git a/tools/fdt_add_pubkey.c b/tools/fdt_add_pubkey.c > new file mode 100755 > index 0000000000..9306ecedd1 > --- /dev/null > +++ b/tools/fdt_add_pubkey.c > @@ -0,0 +1,97 @@ > +#include <image.h> > +#include "fit_common.h" > + > +static const char *cmdname; > + > +static const char *algo_name = "sha1,rsa2048"; /* -a <algo> */ > +static const char *keydir = "."; /* -k <keydir> */ > +static const char *keyname = "key"; /* -n <keyname> */ > +static const char *require_keys; /* -r <conf|image> */ > +static const char *keydest; /* argv[n] */ > + > +static void usage(const char *msg) > +{ > + fprintf(stderr, "Error: %s\n", msg); > + fprintf(stderr, "Usage: %s [-a <algo>] [-k <keydir>] [-n <keyname>] [-r > <conf|image>] <fdt blob>\n", > + cmdname);
The tool should support --help and document the default of these optional parameters that way. Is there an easy way to derive algo from the key? Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux