1# This file is dual licensed under the terms of the Apache License, Version
2# 2.0, and the BSD License. See the LICENSE file in the root of this repository
3# for complete details.
4
5from __future__ import absolute_import, division, print_function
6
7import binascii
8import itertools
9import os
10
11from cryptography.hazmat.backends.openssl.backend import backend
12from cryptography.hazmat.primitives import hashes
13from cryptography.hazmat.primitives.asymmetric import padding, rsa
14
15from tests.utils import load_pkcs1_vectors, load_vectors_from_file
16
17
18def build_vectors(mgf1alg, hashalg, filename):
19    vectors = load_vectors_from_file(filename, load_pkcs1_vectors)
20
21    output = []
22    for vector in vectors:
23        # RSA keys for this must be long enough to accommodate the length of
24        # the underlying hash function. This means we can't use the keys from
25        # the sha1 test vectors for sha512 tests because 1024-bit keys are too
26        # small. Instead we parse the vectors for the test cases, then
27        # generate our own 2048-bit keys for each.
28        private, _ = vector
29        skey = rsa.generate_private_key(65537, 2048, backend)
30        pn = skey.private_numbers()
31        examples = private["examples"]
32        output.append(b"# =============================================")
33        output.append(b"# Example")
34        output.append(b"# Public key")
35        output.append(b"# Modulus:")
36        output.append(format(pn.public_numbers.n, "x"))
37        output.append(b"# Exponent:")
38        output.append(format(pn.public_numbers.e, "x"))
39        output.append(b"# Private key")
40        output.append(b"# Modulus:")
41        output.append(format(pn.public_numbers.n, "x"))
42        output.append(b"# Public exponent:")
43        output.append(format(pn.public_numbers.e, "x"))
44        output.append(b"# Exponent:")
45        output.append(format(pn.d, "x"))
46        output.append(b"# Prime 1:")
47        output.append(format(pn.p, "x"))
48        output.append(b"# Prime 2:")
49        output.append(format(pn.q, "x"))
50        output.append(b"# Prime exponent 1:")
51        output.append(format(pn.dmp1, "x"))
52        output.append(b"# Prime exponent 2:")
53        output.append(format(pn.dmq1, "x"))
54        output.append(b"# Coefficient:")
55        output.append(format(pn.iqmp, "x"))
56        pkey = skey.public_key()
57        vectorkey = rsa.RSAPrivateNumbers(
58            p=private["p"],
59            q=private["q"],
60            d=private["private_exponent"],
61            dmp1=private["dmp1"],
62            dmq1=private["dmq1"],
63            iqmp=private["iqmp"],
64            public_numbers=rsa.RSAPublicNumbers(
65                e=private["public_exponent"],
66                n=private["modulus"]
67            )
68        ).private_key(backend)
69        count = 1
70
71        for example in examples:
72            message = vectorkey.decrypt(
73                binascii.unhexlify(example["encryption"]),
74                padding.OAEP(
75                    mgf=padding.MGF1(algorithm=hashes.SHA1()),
76                    algorithm=hashes.SHA1(),
77                    label=None
78                )
79            )
80            assert message == binascii.unhexlify(example["message"])
81            ct = pkey.encrypt(
82                message,
83                padding.OAEP(
84                    mgf=padding.MGF1(algorithm=mgf1alg),
85                    algorithm=hashalg,
86                    label=None
87                )
88            )
89            output.append(
90                b"# OAEP Example {0} alg={1} mgf1={2}".format(
91                    count, hashalg.name, mgf1alg.name
92                )
93            )
94            count += 1
95            output.append(b"# Message:")
96            output.append(example["message"])
97            output.append(b"# Encryption:")
98            output.append(binascii.hexlify(ct))
99
100    return b"\n".join(output)
101
102
103def write_file(data, filename):
104    with open(filename, "w") as f:
105        f.write(data)
106
107
108oaep_path = os.path.join(
109    "asymmetric", "RSA", "pkcs-1v2-1d2-vec", "oaep-vect.txt"
110)
111hashalgs = [
112    hashes.SHA1(),
113    hashes.SHA224(),
114    hashes.SHA256(),
115    hashes.SHA384(),
116    hashes.SHA512(),
117]
118for hashtuple in itertools.product(hashalgs, hashalgs):
119    if (
120        isinstance(hashtuple[0], hashes.SHA1) and
121        isinstance(hashtuple[1], hashes.SHA1)
122    ):
123        continue
124
125    write_file(
126        build_vectors(hashtuple[0], hashtuple[1], oaep_path),
127        "oaep-{0}-{1}.txt".format(hashtuple[0].name, hashtuple[1].name)
128    )
129