#!/usr/bin/env perl#use warnings;use strict;use Math::BigInt;use Fcntl "SEEK_SET"; die "Format: $0 [-s <systemmap-file>] <vmlinux-file> <keyring-file>\n"    if ($#ARGV != 1 && $#ARGV != 3 ||	$#ARGV == 3 && $ARGV[0] ne "-s"); my $sysmap = "";if ($#ARGV == 3) {    shift;    $sysmap = $ARGV[0];    shift;} my $vmlinux = $ARGV[0];my $keyring = $ARGV[1]; ## Parse the vmlinux section table#open FD, "objdump -h $vmlinux |" || die $vmlinux;my @lines = <FD>;close(FD) || die $vmlinux; my @sections = (); foreach my $line (@lines) {    chomp($line);    if ($line =~ /\s*([0-9]+)\s+(\S+)\s+([0-9a-f]+)\s+([0-9a-f]+)\s+([0-9a-f]+)\s+([0-9a-f]+)\s+2[*][*]([0-9]+)/	) {	my $seg  = $1;	my $name = $2;	my $len  = Math::BigInt->new("0x" . $3);	my $vma  = Math::BigInt->new("0x" . $4);	my $lma  = Math::BigInt->new("0x" . $5);	my $foff = Math::BigInt->new("0x" . $6);	my $align = 2 ** $7; 	push @sections, { name => $name,			  vma => $vma,			  len => $len,			  foff => $foff };    }} print "Have $#sections sections\n"; ## Try and parse the vmlinux symbol table.  If the vmlinux file has been created# from a vmlinuz file with extract-vmlinux then the symbol table will be empty.#open FD, "nm $vmlinux 2>/dev/null |" || die $vmlinux;@lines = <FD>;close(FD) || die $vmlinux; my %symbols = ();my $nr_symbols = 0; sub parse_symbols(@) {    foreach my $line (@_) {	chomp($line);	if ($line =~ /([0-9a-f]+)\s([a-zA-Z])\s(\S+)/	    ) {	    my $addr = "0x" . $1;	    my $type = $2;	    my $name = $3; 	    $symbols{$name} = $addr;	    $nr_symbols++;	}    }}parse_symbols(@lines); if ($nr_symbols == 0 && $sysmap ne "") {    print "No symbols in vmlinux, trying $sysmap\n";     open FD, "<$sysmap" || die $sysmap;    @lines = <FD>;    close(FD) || die $sysmap;    parse_symbols(@lines);} die "No symbols available\n"    if ($nr_symbols == 0); print "Have $nr_symbols symbols\n"; die "Can't find system certificate list"    unless (exists($symbols{"__cert_list_start"}) &&	    exists($symbols{"system_certificate_list_size"})); my $start = Math::BigInt->new($symbols{"__cert_list_start"});my $end;my $size;my $size_sym = Math::BigInt->new($symbols{"system_certificate_list_size"}); open FD, "<$vmlinux" || die $vmlinux;binmode(FD); my $s = undef;foreach my $sec (@sections) {    my $s_name = $sec->{name};    my $s_vma = $sec->{vma};    my $s_len = $sec->{len};    my $s_foff = $sec->{foff};    my $s_vend = $s_vma + $s_len;     next unless ($start >= $s_vma);    next if ($start >= $s_vend);     die "Certificate list size was not found on the same section\n"	if ($size_sym < $s_vma || $size_sym > $s_vend);     die "Cert object in multiple sections: ", $s_name, " and ", $s->{name}, "\n"	if ($s);     my $size_off = $size_sym -$s_vma + $s_foff;    my $packed;    die $vmlinux if (!defined(sysseek(FD, $size_off, SEEK_SET)));    sysread(FD, $packed, 8);    $size = unpack 'L!', $packed;    $end = $start + $size;     printf "Have %u bytes of certs at VMA 0x%x\n", $size, $start;     die "Cert object partially overflows section $s_name\n"	if ($end > $s_vend);     $s = $sec;} die "Cert object not inside a section\n"    unless ($s); print "Certificate list in section ", $s->{name}, "\n"; my $foff = $start - $s->{vma} + $s->{foff}; printf "Certificate list at file offset 0x%x\n", $foff; die $vmlinux if (!defined(sysseek(FD, $foff, SEEK_SET)));my $buf = "";my $len = sysread(FD, $buf, $size);die "$vmlinux" if (!defined($len));die "Short read on $vmlinux\n" if ($len != $size);close(FD) || die $vmlinux; open FD, ">$keyring" || die $keyring;binmode(FD);$len = syswrite(FD, $buf, $size);die "$keyring" if (!defined($len));die "Short write on $keyring\n" if ($len != $size);close(FD) || die $keyring;