#!/usr/bin/env python3 # # SPDX-License-Identifier: BSD-3-Clause import os import struct import sys PROG_NAME = os.path.basename(sys.argv[0]) def create_header(base, size): """Returns a packed MBN header image with the specified base and size. @arg base: integer, specifies the image load address in RAM @arg size: integer, specifies the size of the image @returns: string, the MBN header """ # SBLs require size to be 4 bytes aligned. size = (size + 3) & 0xfffffffc # We currently do not support appending certificates. Signing GPL # code might violate the GPL. So U-Boot will never be signed. So # this is not required for U-Boot. header = [ 0x5, # Type: APPSBL 0x3, # Version: 3 0x0, # Image source pointer base, # Image destination pointer size, # Code Size + Cert Size + Signature Size size, # Code Size base + size, # Destination + Code Size 0x0, # Signature Size base + size, # Destination + Code Size + Signature Size 0x0, # Cert Size ] header_packed = struct.pack('<10I', *header) return header_packed def mkheader(base_addr, infname, outfname): """Prepends the image with the MBN header. @arg base_addr: integer, specifies the image load address in RAM @arg infname: string, image filename @arg outfname: string, output image with header prepended @raises IOError: if reading/writing input/output file fails """ with open(infname, "rb") as infp: image = infp.read() insize = len(image) if base_addr > 0xFFFFFFFF: raise ValueError("invalid base address") if base_addr + insize > 0xFFFFFFFF: raise ValueError("invalid destination range") header = create_header(base_addr, insize) with open(outfname, "wb") as outfp: outfp.write(header) outfp.write(image) def usage(msg=None): """Print command usage. @arg msg: string, error message if any (default: None) """ if msg != None: sys.stderr.write("%s: %s\n" % (PROG_NAME, msg)) print("Usage: %s <base-addr> <input-file> <output-file>" % PROG_NAME) if msg != None: exit(1) def main(): """Main entry function""" if len(sys.argv) != 4: usage("incorrect number of arguments") try: base_addr = int(sys.argv[1], 0) infname = sys.argv[2] outfname = sys.argv[3] except ValueError as e: sys.stderr.write("mkheader: invalid base address '%s'\n" % sys.argv[1]) exit(1) try: mkheader(base_addr, infname, outfname) except IOError as e: sys.stderr.write("%s: %s\n" % (PROG_NAME, e)) exit(1) except ValueError as e: sys.stderr.write("%s: %s\n" % (PROG_NAME, e)) exit(1) if __name__ == "__main__": main()