#!/bin/sh
#
# Sign a module file using the given key.
#
# Format: sign-file <key> <x509> <src-file> <dst-file>
#
scripts=`dirname $0`
CONFIG_MODULE_SIG_SHA512=y
if [ -r .config ]
then
. ./.config
fi
key="$1"
x509="$2"
src="$3"
dst="$4"
if [ ! -r "$key" ]
then
echo "Can't read private key" >&2
exit 2
fi
if [ ! -r "$x509" ]
then
echo "Can't read X.509 certificate" >&2
exit 2
fi
if [ ! -r "$x509.signer" ]
then
echo "Can't read Signer name" >&2
exit 2;
fi
if [ ! -r "$x509.keyid" ]
then
echo "Can't read Key identifier" >&2
exit 2;
fi
#
# Signature parameters
#
algo=1 # Public-key crypto algorithm: RSA
hash= # Digest algorithm
id_type=1 # Identifier type: X.509
#
# Digest the data
#
dgst=
if [ "$CONFIG_MODULE_SIG_SHA1" = "y" ]
then
prologue="0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2B, 0x0E, 0x03, 0x02, 0x1A, 0x05, 0x00, 0x04, 0x14"
dgst=-sha1
hash=2
elif [ "$CONFIG_MODULE_SIG_SHA224" = "y" ]
then
prologue="0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05, 0x00, 0x04, 0x1C"
dgst=-sha224
hash=7
elif [ "$CONFIG_MODULE_SIG_SHA256" = "y" ]
then
prologue="0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20"
dgst=-sha256
hash=4
elif [ "$CONFIG_MODULE_SIG_SHA384" = "y" ]
then
prologue="0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30"
dgst=-sha384
hash=5
elif [ "$CONFIG_MODULE_SIG_SHA512" = "y" ]
then
prologue="0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40"
dgst=-sha512
hash=6
else
echo "$0: Can't determine hash algorithm" >&2
exit 2
fi
(
perl -e "binmode STDOUT; print pack(\"C*\", $prologue)" || exit $?
openssl dgst $dgst -binary $src || exit $?
) >$src.dig || exit $?
#
# Generate the binary signature, which will be just the integer that comprises
# the signature with no metadata attached.
#
openssl rsautl -sign -inkey $key -keyform PEM -in $src.dig -out $src.sig || exit $?
signerlen=`stat -c %s $x509.signer`
keyidlen=`stat -c %s $x509.keyid`
siglen=`stat -c %s $src.sig`
#
# Build the signed binary
#
(
cat $src || exit $?
echo '~Module signature appended~' || exit $?
cat $x509.signer $x509.keyid || exit $?
# Preface each signature integer with a 2-byte BE length
perl -e "binmode STDOUT; print pack(\"n\", $siglen)" || exit $?
cat $src.sig || exit $?
# Generate the information block
perl -e "binmode STDOUT; print pack(\"CCCCCxxxN\", $algo, $hash, $id_type, $signerlen, $keyidlen, $siglen + 2)" || exit $?
) >$dst~ || exit $?
# Permit in-place signing
mv $dst~ $dst || exit $?
