xref: /optee_os/scripts/pem_to_pub_c.py (revision bc420748bfc44a9e09000a3966fc59e9e0219df4)
1#!/usr/bin/env python
2#
3# Copyright (c) 2015, Linaro Limited
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions are met:
8#
9# 1. Redistributions of source code must retain the above copyright notice,
10# this list of conditions and the following disclaimer.
11#
12# 2. Redistributions in binary form must reproduce the above copyright notice,
13# this list of conditions and the following disclaimer in the documentation
14# and/or other materials provided with the distribution.
15#
16# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26# POSSIBILITY OF SUCH DAMAGE.
27#
28
29def get_args():
30	import argparse
31
32	parser = argparse.ArgumentParser()
33	parser.add_argument('--prefix', required=True, \
34		help='Prefix for the public key exponent and modulus in c file')
35
36	parser.add_argument('--out', required=True, \
37		help='Name of c file for the public key')
38
39	parser.add_argument('--key', required=True, help='Name of key file')
40
41	return parser.parse_args()
42
43def main():
44	import array
45	from Crypto.PublicKey import RSA
46	from Crypto.Util.number import long_to_bytes
47
48	args = get_args();
49
50	f = open(args.key, 'r')
51	key = RSA.importKey(f.read())
52	f.close
53
54	f = open(args.out, 'w')
55
56	f.write("#include <stdint.h>\n");
57	f.write("#include <stddef.h>\n\n");
58
59	f.write("const uint32_t " + args.prefix + "_exponent = " +
60		str(key.publickey().e) + ";\n\n")
61
62	f.write("const uint8_t " + args.prefix + "_modulus[] = {\n")
63	i = 0;
64	for x in array.array("B", long_to_bytes(key.publickey().n)):
65		f.write("0x" + '{0:02x}'.format(x) + ",")
66		i = i + 1;
67		if i % 8 == 0:
68			f.write("\n");
69		else:
70			f.write(" ");
71	f.write("};\n");
72
73	f.write("const size_t " + args.prefix + "_modulus_size = sizeof(" + \
74		args.prefix + "_modulus);\n")
75
76	f.close()
77
78if __name__ == "__main__":
79	main()
80