[linux.git] / scripts / sign-file

#!/usr/bin/perl -w
#
# Sign a module file using the given key.
#

my $USAGE =
"Usage: scripts/sign-file [-v] <hash algo> <key> <x509> <module> [<dest>]\n" .
"       scripts/sign-file [-v] -s <raw sig> <hash algo> <x509> <module> [<dest>]\n";

use strict;
use FileHandle;
use IPC::Open2;
use Getopt::Std;

my %opts;
getopts('vs:', \%opts) or die $USAGE;
my $verbose = $opts{'v'};
my $signature_file = $opts{'s'};

die $USAGE if ($#ARGV > 4);
die $USAGE if (!$signature_file && $#ARGV < 3 || $signature_file && $#ARGV < 2);

my $dgst = shift @ARGV;
my $private_key;
if (!$signature_file) {
	$private_key = shift @ARGV;
}
my $x509 = shift @ARGV;
my $module = shift @ARGV;
my ($dest, $keep_orig);
if (@ARGV) {
	$dest = $ARGV[0];
	$keep_orig = 1;
} else {
	$dest = $module . "~";
}

die "Can't read private key\n" if (!$signature_file && !-r $private_key);
die "Can't read signature file\n" if ($signature_file && !-r $signature_file);
die "Can't read X.509 certificate\n" unless (-r $x509);
die "Can't read module\n" unless (-r $module);

#
# Function to read the contents of a file into a variable.
#
sub read_file($)
{
    my ($file) = @_;
    my $contents;
    my $len;

    open(FD, "<$file") || die $file;
    binmode FD;
    my @st = stat(FD);
    die $file if (!@st);
    $len = read(FD, $contents, $st[7]) || die $file;
    close(FD) || die $file;
    die "$file: Wanted length ", $st[7], ", got ", $len, "\n"
	if ($len != $st[7]);
    return $contents;
}

###############################################################################
#
# First of all, we have to parse the X.509 certificate to find certain details
# about it.
#
# We read the DER-encoded X509 certificate and parse it to extract the Subject
# name and Subject Key Identifier.  Theis provides the data we need to build
# the certificate identifier.
#
# The signer's name part of the identifier is fabricated from the commonName,
# the organizationName or the emailAddress components of the X.509 subject
# name.
#
# The subject key ID is used to select which of that signer's certificates
# we're intending to use to sign the module.
#
###############################################################################
my $x509_certificate = read_file($x509);

my $UNIV = 0 << 6;
my $APPL = 1 << 6;
my $CONT = 2 << 6;
my $PRIV = 3 << 6;

my $CONS = 0x20;

my $BOOLEAN	= 0x01;
my $INTEGER	= 0x02;
my $BIT_STRING	= 0x03;
my $OCTET_STRING = 0x04;
my $NULL	= 0x05;
my $OBJ_ID	= 0x06;
my $UTF8String	= 0x0c;
my $SEQUENCE	= 0x10;
my $SET		= 0x11;
my $UTCTime	= 0x17;
my $GeneralizedTime = 0x18;

my %OIDs = (
    pack("CCC", 85, 4, 3)	=> "commonName",
    pack("CCC", 85, 4, 6)	=> "countryName",
    pack("CCC", 85, 4, 10)	=> "organizationName",
    pack("CCC", 85, 4, 11)	=> "organizationUnitName",
    pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 1) => "rsaEncryption",
    pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 5) => "sha1WithRSAEncryption",
    pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 9, 1) => "emailAddress",
    pack("CCC", 85, 29, 35)	=> "authorityKeyIdentifier",
    pack("CCC", 85, 29, 14)	=> "subjectKeyIdentifier",
    pack("CCC", 85, 29, 19)	=> "basicConstraints"
);

###############################################################################
#
# Extract an ASN.1 element from a string and return information about it.
#
###############################################################################
sub asn1_extract($$@)
{
    my ($cursor, $expected_tag, $optional) = @_;

    return [ -1 ]
	if ($cursor->[1] == 0 && $optional);

    die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (elem ", $cursor->[1], ")\n"
	if ($cursor->[1] < 2);

    my ($tag, $len) = unpack("CC", substr(${$cursor->[2]}, $cursor->[0], 2));

    if ($expected_tag != -1 && $tag != $expected_tag) {
	return [ -1 ]
	    if ($optional);
	die $x509, ": ", $cursor->[0], ": ASN.1 unexpected tag (", $tag,
	" not ", $expected_tag, ")\n";
    }

    $cursor->[0] += 2;
    $cursor->[1] -= 2;

    die $x509, ": ", $cursor->[0], ": ASN.1 long tag\n"
	if (($tag & 0x1f) == 0x1f);
    die $x509, ": ", $cursor->[0], ": ASN.1 indefinite length\n"
	if ($len == 0x80);

    if ($len > 0x80) {
	my $l = $len - 0x80;
	die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (len len $l)\n"
	    if ($cursor->[1] < $l);

	if ($l == 0x1) {
	    $len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1));
	} elsif ($l == 0x2) {
	    $len = unpack("n", substr(${$cursor->[2]}, $cursor->[0], 2));
	} elsif ($l == 0x3) {
	    $len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1)) << 16;
	    $len = unpack("n", substr(${$cursor->[2]}, $cursor->[0] + 1, 2));
	} elsif ($l == 0x4) {
	    $len = unpack("N", substr(${$cursor->[2]}, $cursor->[0], 4));
	} else {
	    die $x509, ": ", $cursor->[0], ": ASN.1 element too long (", $l, ")\n";
	}

	$cursor->[0] += $l;
	$cursor->[1] -= $l;
    }

    die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (", $len, ")\n"
	if ($cursor->[1] < $len);

    my $ret = [ $tag, [ $cursor->[0], $len, $cursor->[2] ] ];
    $cursor->[0] += $len;
    $cursor->[1] -= $len;

    return $ret;
}

###############################################################################
#
# Retrieve the data referred to by a cursor
#
###############################################################################
sub asn1_retrieve($)
{
    my ($cursor) = @_;
    my ($offset, $len, $data) = @$cursor;
    return substr($$data, $offset, $len);
}

###############################################################################
#
# Roughly parse the X.509 certificate
#
###############################################################################
my $cursor = [ 0, length($x509_certificate), \$x509_certificate ];

my $cert = asn1_extract($cursor, $UNIV | $CONS | $SEQUENCE);
my $tbs = asn1_extract($cert->[1], $UNIV | $CONS | $SEQUENCE);
my $version = asn1_extract($tbs->[1], $CONT | $CONS | 0, 1);
my $serial_number = asn1_extract($tbs->[1], $UNIV | $INTEGER);
my $sig_type = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
my $issuer = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
my $validity = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
my $subject = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
my $key = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
my $issuer_uid = asn1_extract($tbs->[1], $CONT | $CONS | 1, 1);
my $subject_uid = asn1_extract($tbs->[1], $CONT | $CONS | 2, 1);
my $extension_list = asn1_extract($tbs->[1], $CONT | $CONS | 3, 1);

my $subject_key_id = ();
my $authority_key_id = ();

#
# Parse the extension list
#
if ($extension_list->[0] != -1) {
    my $extensions = asn1_extract($extension_list->[1], $UNIV | $CONS | $SEQUENCE);

    while ($extensions->[1]->[1] > 0) {
	my $ext = asn1_extract($extensions->[1], $UNIV | $CONS | $SEQUENCE);
	my $x_oid = asn1_extract($ext->[1], $UNIV | $OBJ_ID);
	my $x_crit = asn1_extract($ext->[1], $UNIV | $BOOLEAN, 1);
	my $x_val = asn1_extract($ext->[1], $UNIV | $OCTET_STRING);

	my $raw_oid = asn1_retrieve($x_oid->[1]);
	next if (!exists($OIDs{$raw_oid}));
	my $x_type = $OIDs{$raw_oid};

	my $raw_value = asn1_retrieve($x_val->[1]);

	if ($x_type eq "subjectKeyIdentifier") {
	    my $vcursor = [ 0, length($raw_value), \$raw_value ];

	    $subject_key_id = asn1_extract($vcursor, $UNIV | $OCTET_STRING);
	}
    }
}

###############################################################################
#
# Determine what we're going to use as the signer's name.  In order of
# preference, take one of: commonName, organizationName or emailAddress.
#
###############################################################################
my $org = "";
my $cn = "";
my $email = "";

while ($subject->[1]->[1] > 0) {
    my $rdn = asn1_extract($subject->[1], $UNIV | $CONS | $SET);
    my $attr = asn1_extract($rdn->[1], $UNIV | $CONS | $SEQUENCE);
    my $n_oid = asn1_extract($attr->[1], $UNIV | $OBJ_ID);
    my $n_val = asn1_extract($attr->[1], -1);

    my $raw_oid = asn1_retrieve($n_oid->[1]);
    next if (!exists($OIDs{$raw_oid}));
    my $n_type = $OIDs{$raw_oid};

    my $raw_value = asn1_retrieve($n_val->[1]);

    if ($n_type eq "organizationName") {
	$org = $raw_value;
    } elsif ($n_type eq "commonName") {
	$cn = $raw_value;
    } elsif ($n_type eq "emailAddress") {
	$email = $raw_value;
    }
}

my $signers_name = $email;

if ($org && $cn) {
    # Don't use the organizationName if the commonName repeats it
    if (length($org) <= length($cn) &&
	substr($cn, 0, length($org)) eq $org) {
	$signers_name = $cn;
	goto got_id_name;
    }

    # Or a signifcant chunk of it
    if (length($org) >= 7 &&
	length($cn) >= 7 &&
	substr($cn, 0, 7) eq substr($org, 0, 7)) {
	$signers_name = $cn;
	goto got_id_name;
    }

    $signers_name = $org . ": " . $cn;
} elsif ($org) {
    $signers_name = $org;
} elsif ($cn) {
    $signers_name = $cn;
}

got_id_name:

die $x509, ": ", "X.509: Couldn't find the Subject Key Identifier extension\n"
    if (!$subject_key_id);

my $key_identifier = asn1_retrieve($subject_key_id->[1]);

###############################################################################
#
# Create and attach the module signature
#
###############################################################################

#
# Signature parameters
#
my $algo = 1;		# Public-key crypto algorithm: RSA
my $hash = 0;		# Digest algorithm
my $id_type = 1;	# Identifier type: X.509

#
# Digest the data
#
my $prologue;
if ($dgst eq "sha1") {
    $prologue = pack("C*",
		     0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
		     0x2B, 0x0E, 0x03, 0x02, 0x1A,
		     0x05, 0x00, 0x04, 0x14);
    $hash = 2;
} elsif ($dgst eq "sha224") {
    $prologue = pack("C*",
		     0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
		     0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
		     0x05, 0x00, 0x04, 0x1C);
    $hash = 7;
} elsif ($dgst eq "sha256") {
    $prologue = pack("C*",
		     0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
		     0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
		     0x05, 0x00, 0x04, 0x20);
    $hash = 4;
} elsif ($dgst eq "sha384") {
    $prologue = pack("C*",
		     0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
		     0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
		     0x05, 0x00, 0x04, 0x30);
    $hash = 5;
} elsif ($dgst eq "sha512") {
    $prologue = pack("C*",
		     0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
		     0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
		     0x05, 0x00, 0x04, 0x40);
    $hash = 6;
} else {
    die "Unknown hash algorithm: $dgst\n";
}

my $signature;
if ($signature_file) {
	$signature = read_file($signature_file);
} else {
	#
	# Generate the digest and read from openssl's stdout
	#
	my $digest;
	$digest = readpipe("openssl dgst -$dgst -binary $module") || die "openssl dgst";

	#
	# Generate the binary signature, which will be just the integer that
	# comprises the signature with no metadata attached.
	#
	my $pid;
	$pid = open2(*read_from, *write_to,
		     "openssl rsautl -sign -inkey $private_key -keyform PEM") ||
	    die "openssl rsautl";
	binmode write_to;
	print write_to $prologue . $digest || die "pipe to openssl rsautl";
	close(write_to) || die "pipe to openssl rsautl";

	binmode read_from;
	read(read_from, $signature, 4096) || die "pipe from openssl rsautl";
	close(read_from) || die "pipe from openssl rsautl";
	waitpid($pid, 0) || die;
	die "openssl rsautl died: $?" if ($? >> 8);
}
$signature = pack("n", length($signature)) . $signature,

#
# Build the signed binary
#
my $unsigned_module = read_file($module);

my $magic_number = "~Module signature appended~\n";

my $info = pack("CCCCCxxxN",
		$algo, $hash, $id_type,
		length($signers_name),
		length($key_identifier),
		length($signature));

if ($verbose) {
    print "Size of unsigned module: ", length($unsigned_module), "\n";
    print "Size of signer's name  : ", length($signers_name), "\n";
    print "Size of key identifier : ", length($key_identifier), "\n";
    print "Size of signature      : ", length($signature), "\n";
    print "Size of informaton     : ", length($info), "\n";
    print "Size of magic number   : ", length($magic_number), "\n";
    print "Signer's name          : '", $signers_name, "'\n";
    print "Digest                 : $dgst\n";
}

open(FD, ">$dest") || die $dest;
binmode FD;
print FD
    $unsigned_module,
    $signers_name,
    $key_identifier,
    $signature,
    $info,
    $magic_number
    ;
close FD || die $dest;

if (!$keep_orig) {
    rename($dest, $module) || die $module;
}
Commit	Line	Data
b37d1bfb	1	#!/usr/bin/perl -w
80d65e58 DH	2	#
	3	# Sign a module file using the given key.
	4	#
1c37c054 MM	5
	6	my $USAGE =
	7	"Usage: scripts/sign-file [-v] <hash algo> <key> <x509> <module> [<dest>]\n" .
	8	" scripts/sign-file [-v] -s <raw sig> <hash algo> <x509> <module> [<dest>]\n";
	9
b37d1bfb DH	10	use strict;
	11	use FileHandle;
	12	use IPC::Open2;
1c37c054	13	use Getopt::Std;
b37d1bfb	14
1c37c054 MM	15	my %opts;
	16	getopts('vs:', \%opts) or die $USAGE;
	17	my $verbose = $opts{'v'};
	18	my $signature_file = $opts{'s'};
b37d1bfb	19
1c37c054 MM	20	die $USAGE if ($#ARGV > 4);
1c37c054 MM	21	die $USAGE if (!$signature_file && $#ARGV < 3 \|\| $signature_file && $#ARGV < 2);
b37d1bfb	22
1c37c054 MM	23	my $dgst = shift @ARGV;
	24	my $private_key;
	25	if (!$signature_file) {
	26	$private_key = shift @ARGV;
	27	}
	28	my $x509 = shift @ARGV;
	29	my $module = shift @ARGV;
	30	my ($dest, $keep_orig);
	31	if (@ARGV) {
	32	$dest = $ARGV[0];
	33	$keep_orig = 1;
	34	} else {
	35	$dest = $module . "~";
	36	}
b37d1bfb	37
1c37c054 MM	38	die "Can't read private key\n" if (!$signature_file && !-r $private_key);
1c37c054 MM	39	die "Can't read signature file\n" if ($signature_file && !-r $signature_file);
b37d1bfb DH	40	die "Can't read X.509 certificate\n" unless (-r $x509);
	41	die "Can't read module\n" unless (-r $module);
	42
b37d1bfb DH	43	#
	44	# Function to read the contents of a file into a variable.
	45	#
	46	sub read_file($)
	47	{
	48	my ($file) = @_;
	49	my $contents;
	50	my $len;
	51
	52	open(FD, "<$file") \|\| die $file;
	53	binmode FD;
	54	my @st = stat(FD);
	55	die $file if (!@st);
	56	$len = read(FD, $contents, $st[7]) \|\| die $file;
	57	close(FD) \|\| die $file;
	58	die "$file: Wanted length ", $st[7], ", got ", $len, "\n"
	59	if ($len != $st[7]);
	60	return $contents;
	61	}
	62
	63	###############################################################################
	64	#
	65	# First of all, we have to parse the X.509 certificate to find certain details
	66	# about it.
	67	#
	68	# We read the DER-encoded X509 certificate and parse it to extract the Subject
	69	# name and Subject Key Identifier. Theis provides the data we need to build
	70	# the certificate identifier.
	71	#
	72	# The signer's name part of the identifier is fabricated from the commonName,
	73	# the organizationName or the emailAddress components of the X.509 subject
	74	# name.
	75	#
	76	# The subject key ID is used to select which of that signer's certificates
	77	# we're intending to use to sign the module.
	78	#
	79	###############################################################################
	80	my $x509_certificate = read_file($x509);
80d65e58	81
b37d1bfb DH	82	my $UNIV = 0 << 6;
	83	my $APPL = 1 << 6;
	84	my $CONT = 2 << 6;
	85	my $PRIV = 3 << 6;
80d65e58	86
b37d1bfb	87	my $CONS = 0x20;
80d65e58	88
b37d1bfb DH	89	my $BOOLEAN = 0x01;
	90	my $INTEGER = 0x02;
	91	my $BIT_STRING = 0x03;
	92	my $OCTET_STRING = 0x04;
	93	my $NULL = 0x05;
	94	my $OBJ_ID = 0x06;
	95	my $UTF8String = 0x0c;
	96	my $SEQUENCE = 0x10;
	97	my $SET = 0x11;
	98	my $UTCTime = 0x17;
	99	my $GeneralizedTime = 0x18;
80d65e58	100
b37d1bfb DH	101	my %OIDs = (
	102	pack("CCC", 85, 4, 3) => "commonName",
	103	pack("CCC", 85, 4, 6) => "countryName",
	104	pack("CCC", 85, 4, 10) => "organizationName",
	105	pack("CCC", 85, 4, 11) => "organizationUnitName",
	106	pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 1) => "rsaEncryption",
	107	pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 5) => "sha1WithRSAEncryption",
	108	pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 9, 1) => "emailAddress",
	109	pack("CCC", 85, 29, 35) => "authorityKeyIdentifier",
	110	pack("CCC", 85, 29, 14) => "subjectKeyIdentifier",
	111	pack("CCC", 85, 29, 19) => "basicConstraints"
	112	);
	113
	114	###############################################################################
	115	#
	116	# Extract an ASN.1 element from a string and return information about it.
	117	#
	118	###############################################################################
	119	sub asn1_extract($$@)
	120	{
	121	my ($cursor, $expected_tag, $optional) = @_;
	122
	123	return [ -1 ]
	124	if ($cursor->[1] == 0 && $optional);
	125
	126	die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (elem ", $cursor->[1], ")\n"
	127	if ($cursor->[1] < 2);
	128
	129	my ($tag, $len) = unpack("CC", substr(${$cursor->[2]}, $cursor->[0], 2));
	130
	131	if ($expected_tag != -1 && $tag != $expected_tag) {
	132	return [ -1 ]
	133	if ($optional);
	134	die $x509, ": ", $cursor->[0], ": ASN.1 unexpected tag (", $tag,
	135	" not ", $expected_tag, ")\n";
	136	}
	137
	138	$cursor->[0] += 2;
	139	$cursor->[1] -= 2;
	140
	141	die $x509, ": ", $cursor->[0], ": ASN.1 long tag\n"
	142	if (($tag & 0x1f) == 0x1f);
	143	die $x509, ": ", $cursor->[0], ": ASN.1 indefinite length\n"
	144	if ($len == 0x80);
	145
	146	if ($len > 0x80) {
	147	my $l = $len - 0x80;
	148	die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (len len $l)\n"
	149	if ($cursor->[1] < $l);
	150
	151	if ($l == 0x1) {
	152	$len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1));
916492b1	153	} elsif ($l == 0x2) {
b37d1bfb	154	$len = unpack("n", substr(${$cursor->[2]}, $cursor->[0], 2));
916492b1	155	} elsif ($l == 0x3) {
b37d1bfb DH	156	$len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1)) << 16;
b37d1bfb DH	157	$len = unpack("n", substr(${$cursor->[2]}, $cursor->[0] + 1, 2));
916492b1	158	} elsif ($l == 0x4) {
b37d1bfb DH	159	$len = unpack("N", substr(${$cursor->[2]}, $cursor->[0], 4));
	160	} else {
	161	die $x509, ": ", $cursor->[0], ": ASN.1 element too long (", $l, ")\n";
	162	}
	163
	164	$cursor->[0] += $l;
	165	$cursor->[1] -= $l;
	166	}
	167
	168	die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (", $len, ")\n"
	169	if ($cursor->[1] < $len);
	170
	171	my $ret = [ $tag, [ $cursor->[0], $len, $cursor->[2] ] ];
	172	$cursor->[0] += $len;
	173	$cursor->[1] -= $len;
	174
	175	return $ret;
	176	}
	177
	178	###############################################################################
	179	#
	180	# Retrieve the data referred to by a cursor
	181	#
	182	###############################################################################
	183	sub asn1_retrieve($)
	184	{
	185	my ($cursor) = @_;
	186	my ($offset, $len, $data) = @$cursor;
	187	return substr($$data, $offset, $len);
	188	}
	189
	190	###############################################################################
	191	#
	192	# Roughly parse the X.509 certificate
	193	#
	194	###############################################################################
	195	my $cursor = [ 0, length($x509_certificate), \$x509_certificate ];
	196
	197	my $cert = asn1_extract($cursor, $UNIV \| $CONS \| $SEQUENCE);
	198	my $tbs = asn1_extract($cert->[1], $UNIV \| $CONS \| $SEQUENCE);
	199	my $version = asn1_extract($tbs->[1], $CONT \| $CONS \| 0, 1);
	200	my $serial_number = asn1_extract($tbs->[1], $UNIV \| $INTEGER);
	201	my $sig_type = asn1_extract($tbs->[1], $UNIV \| $CONS \| $SEQUENCE);
	202	my $issuer = asn1_extract($tbs->[1], $UNIV \| $CONS \| $SEQUENCE);
	203	my $validity = asn1_extract($tbs->[1], $UNIV \| $CONS \| $SEQUENCE);
	204	my $subject = asn1_extract($tbs->[1], $UNIV \| $CONS \| $SEQUENCE);
	205	my $key = asn1_extract($tbs->[1], $UNIV \| $CONS \| $SEQUENCE);
	206	my $issuer_uid = asn1_extract($tbs->[1], $CONT \| $CONS \| 1, 1);
	207	my $subject_uid = asn1_extract($tbs->[1], $CONT \| $CONS \| 2, 1);
	208	my $extension_list = asn1_extract($tbs->[1], $CONT \| $CONS \| 3, 1);
	209
	210	my $subject_key_id = ();
	211	my $authority_key_id = ();
	212
	213	#
	214	# Parse the extension list
	215	#
	216	if ($extension_list->[0] != -1) {
	217	my $extensions = asn1_extract($extension_list->[1], $UNIV \| $CONS \| $SEQUENCE);
	218
	219	while ($extensions->[1]->[1] > 0) {
	220	my $ext = asn1_extract($extensions->[1], $UNIV \| $CONS \| $SEQUENCE);
	221	my $x_oid = asn1_extract($ext->[1], $UNIV \| $OBJ_ID);
	222	my $x_crit = asn1_extract($ext->[1], $UNIV \| $BOOLEAN, 1);
223	my $x_val = asn1_extract($ext->[1], $UNIV \| $OCTET_STRING);
224
225	my $raw_oid = asn1_retrieve($x_oid->[1]);
226	next if (!exists($OIDs{$raw_oid}));
227	my $x_type = $OIDs{$raw_oid};
228
229	my $raw_value = asn1_retrieve($x_val->[1]);
230
231	if ($x_type eq "subjectKeyIdentifier") {
232	my $vcursor = [ 0, length($raw_value), \$raw_value ];
233
234	$subject_key_id = asn1_extract($vcursor, $UNIV \| $OCTET_STRING);
235	}
236	}
237	}
238
239	###############################################################################
240	#
241	# Determine what we're going to use as the signer's name. In order of
242	# preference, take one of: commonName, organizationName or emailAddress.
243	#
244	###############################################################################
245	my $org = "";
246	my $cn = "";
247	my $email = "";
248
249	while ($subject->[1]->[1] > 0) {
250	my $rdn = asn1_extract($subject->[1], $UNIV \| $CONS \| $SET);
251	my $attr = asn1_extract($rdn->[1], $UNIV \| $CONS \| $SEQUENCE);
252	my $n_oid = asn1_extract($attr->[1], $UNIV \| $OBJ_ID);
253	my $n_val = asn1_extract($attr->[1], -1);
254
255	my $raw_oid = asn1_retrieve($n_oid->[1]);
256	next if (!exists($OIDs{$raw_oid}));
257	my $n_type = $OIDs{$raw_oid};
258
259	my $raw_value = asn1_retrieve($n_val->[1]);
260
261	if ($n_type eq "organizationName") {
262	$org = $raw_value;
263	} elsif ($n_type eq "commonName") {
264	$cn = $raw_value;
265	} elsif ($n_type eq "emailAddress") {
266	$email = $raw_value;
267	}
268	}
269
270	my $signers_name = $email;
271
272	if ($org && $cn) {
273	# Don't use the organizationName if the commonName repeats it
274	if (length($org) <= length($cn) &&
275	substr($cn, 0, length($org)) eq $org) {
276	$signers_name = $cn;
277	goto got_id_name;
278	}
279
280	# Or a signifcant chunk of it
281	if (length($org) >= 7 &&
282	length($cn) >= 7 &&
283	substr($cn, 0, 7) eq substr($org, 0, 7)) {
284	$signers_name = $cn;
285	goto got_id_name;
286	}
287
288	$signers_name = $org . ": " . $cn;
289	} elsif ($org) {
290	$signers_name = $org;
291	} elsif ($cn) {
292	$signers_name = $cn;
293	}
294
295	got_id_name:
296
297	die $x509, ": ", "X.509: Couldn't find the Subject Key Identifier extension\n"
298	if (!$subject_key_id);
299
300	my $key_identifier = asn1_retrieve($subject_key_id->[1]);
301
302	###############################################################################
303	#
304	# Create and attach the module signature
305	#
306	###############################################################################
80d65e58 DH	307
	308	#
	309	# Signature parameters
	310	#
b37d1bfb DH	311	my $algo = 1; # Public-key crypto algorithm: RSA
	312	my $hash = 0; # Digest algorithm
	313	my $id_type = 1; # Identifier type: X.509
80d65e58 DH	314
	315	#
	316	# Digest the data
	317	#
4bc9410c MM	318	my $prologue;
4bc9410c MM	319	if ($dgst eq "sha1") {
b37d1bfb DH	320	$prologue = pack("C*",
	321	0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
	322	0x2B, 0x0E, 0x03, 0x02, 0x1A,
	323	0x05, 0x00, 0x04, 0x14);
b37d1bfb	324	$hash = 2;
4bc9410c	325	} elsif ($dgst eq "sha224") {
b37d1bfb DH	326	$prologue = pack("C*",
	327	0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
	328	0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
	329	0x05, 0x00, 0x04, 0x1C);
b37d1bfb	330	$hash = 7;
4bc9410c	331	} elsif ($dgst eq "sha256") {
b37d1bfb DH	332	$prologue = pack("C*",
	333	0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
	334	0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
	335	0x05, 0x00, 0x04, 0x20);
b37d1bfb	336	$hash = 4;
4bc9410c	337	} elsif ($dgst eq "sha384") {
b37d1bfb DH	338	$prologue = pack("C*",
	339	0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
	340	0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
	341	0x05, 0x00, 0x04, 0x30);
b37d1bfb	342	$hash = 5;
4bc9410c	343	} elsif ($dgst eq "sha512") {
b37d1bfb DH	344	$prologue = pack("C*",
	345	0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
	346	0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
	347	0x05, 0x00, 0x04, 0x40);
b37d1bfb DH	348	$hash = 6;
b37d1bfb DH	349	} else {
4bc9410c	350	die "Unknown hash algorithm: $dgst\n";
b37d1bfb DH	351	}
b37d1bfb DH	352
b37d1bfb	353	my $signature;
1c37c054 MM	354	if ($signature_file) {
	355	$signature = read_file($signature_file);
	356	} else {
	357	#
	358	# Generate the digest and read from openssl's stdout
	359	#
	360	my $digest;
	361	$digest = readpipe("openssl dgst -$dgst -binary $module") \|\| die "openssl dgst";
	362
	363	#
	364	# Generate the binary signature, which will be just the integer that
	365	# comprises the signature with no metadata attached.
	366	#
	367	my $pid;
	368	$pid = open2(read_from, write_to,
	369	"openssl rsautl -sign -inkey $private_key -keyform PEM") \|\|
	370	die "openssl rsautl";
	371	binmode write_to;
	372	print write_to $prologue . $digest \|\| die "pipe to openssl rsautl";
	373	close(write_to) \|\| die "pipe to openssl rsautl";
	374
	375	binmode read_from;
	376	read(read_from, $signature, 4096) \|\| die "pipe from openssl rsautl";
	377	close(read_from) \|\| die "pipe from openssl rsautl";
	378	waitpid($pid, 0) \|\| die;
	379	die "openssl rsautl died: $?" if ($? >> 8);
	380	}
b37d1bfb	381	$signature = pack("n", length($signature)) . $signature,
e2a666d5	382
80d65e58 DH	383	#
	384	# Build the signed binary
	385	#
b37d1bfb DH	386	my $unsigned_module = read_file($module);
	387
	388	my $magic_number = "~Module signature appended~\n";
	389
	390	my $info = pack("CCCCCxxxN",
	391	$algo, $hash, $id_type,
	392	length($signers_name),
	393	length($key_identifier),
	394	length($signature));
80d65e58	395
b37d1bfb DH	396	if ($verbose) {
b37d1bfb DH	397	print "Size of unsigned module: ", length($unsigned_module), "\n";
b37d1bfb DH	398	print "Size of signer's name : ", length($signers_name), "\n";
	399	print "Size of key identifier : ", length($key_identifier), "\n";
	400	print "Size of signature : ", length($signature), "\n";
	401	print "Size of informaton : ", length($info), "\n";
caabe240	402	print "Size of magic number : ", length($magic_number), "\n";
b37d1bfb DH	403	print "Signer's name : '", $signers_name, "'\n";
	404	print "Digest : $dgst\n";
	405	}
80d65e58	406
b37d1bfb DH	407	open(FD, ">$dest") \|\| die $dest;
	408	binmode FD;
	409	print FD
	410	$unsigned_module,
b37d1bfb DH	411	$signers_name,
	412	$key_identifier,
	413	$signature,
caabe240 DH	414	$info,
caabe240 DH	415	$magic_number
b37d1bfb DH	416	;
b37d1bfb DH	417	close FD \|\| die $dest;
80d65e58	418
1c37c054	419	if (!$keep_orig) {
b37d1bfb DH	420	rename($dest, $module) \|\| die $module;
b37d1bfb DH	421	}