xref: /optee_os/scripts/pem_to_pub_c.py (revision 1bb929836182ecb96d2d9d268daa807c67596396)
1#!/usr/bin/env python
2# SPDX-License-Identifier: BSD-2-Clause
3#
4# Copyright (c) 2015, Linaro Limited
5# All rights reserved.
6#
7# Redistribution and use in source and binary forms, with or without
8# modification, are permitted provided that the following conditions are met:
9#
10# 1. Redistributions of source code must retain the above copyright notice,
11# this list of conditions and the following disclaimer.
12#
13# 2. Redistributions in binary form must reproduce the above copyright notice,
14# this list of conditions and the following disclaimer in the documentation
15# and/or other materials provided with the distribution.
16#
17# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
21# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27# POSSIBILITY OF SUCH DAMAGE.
28#
29
30def get_args():
31	import argparse
32
33	parser = argparse.ArgumentParser()
34	parser.add_argument('--prefix', required=True, \
35		help='Prefix for the public key exponent and modulus in c file')
36
37	parser.add_argument('--out', required=True, \
38		help='Name of c file for the public key')
39
40	parser.add_argument('--key', required=True, help='Name of key file')
41
42	return parser.parse_args()
43
44def main():
45	import array
46	from Crypto.PublicKey import RSA
47	from Crypto.Util.number import long_to_bytes
48
49	args = get_args();
50
51	f = open(args.key, 'r')
52	key = RSA.importKey(f.read())
53	f.close
54
55	f = open(args.out, 'w')
56
57	f.write("#include <stdint.h>\n");
58	f.write("#include <stddef.h>\n\n");
59
60	f.write("const uint32_t " + args.prefix + "_exponent = " +
61		str(key.publickey().e) + ";\n\n")
62
63	f.write("const uint8_t " + args.prefix + "_modulus[] = {\n")
64	i = 0;
65	for x in array.array("B", long_to_bytes(key.publickey().n)):
66		f.write("0x" + '{0:02x}'.format(x) + ",")
67		i = i + 1;
68		if i % 8 == 0:
69			f.write("\n");
70		else:
71			f.write(" ");
72	f.write("};\n");
73
74	f.write("const size_t " + args.prefix + "_modulus_size = sizeof(" + \
75		args.prefix + "_modulus);\n")
76
77	f.close()
78
79if __name__ == "__main__":
80	main()
81