scripts/extract-sys-certs.pl

Source file repositories/reference/linux-study-clean/scripts/extract-sys-certs.pl

File Facts

System
Linux kernel
Corpus path
scripts/extract-sys-certs.pl
Extension
.pl
Size
3836 bytes
Lines
160
Domain
Support Tooling And Documentation
Bucket
scripts
Inferred role
Support Tooling And Documentation: scripts
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

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);

Annotation

Implementation Notes