mcuboot/scripts/imgtool/keys/rsa_test.py

137 lines
4.4 KiB
Python

"""
Tests for RSA keys
"""
# SPDX-License-Identifier: Apache-2.0
import io
import os
import sys
import tempfile
import unittest
from cryptography.exceptions import InvalidSignature
from cryptography.hazmat.primitives.asymmetric.padding import PSS, MGF1
from cryptography.hazmat.primitives.hashes import SHA256
# Setup sys path so 'imgtool' is in it.
sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__),
'../..')))
from imgtool.keys import load, RSA, RSAUsageError
from imgtool.keys.rsa import RSA_KEY_SIZES
class KeyGeneration(unittest.TestCase):
def setUp(self):
self.test_dir = tempfile.TemporaryDirectory()
def tname(self, base):
return os.path.join(self.test_dir.name, base)
def tearDown(self):
self.test_dir.cleanup()
def test_keygen(self):
# Try generating a RSA key with non-supported size
with self.assertRaises(RSAUsageError):
RSA.generate(key_size=1024)
for key_size in RSA_KEY_SIZES:
name1 = self.tname("keygen.pem")
k = RSA.generate(key_size=key_size)
k.export_private(name1, b'secret')
# Try loading the key without a password.
self.assertIsNone(load(name1))
k2 = load(name1, b'secret')
pubname = self.tname('keygen-pub.pem')
k2.export_public(pubname)
pk2 = load(pubname)
# We should be able to export the public key from the loaded
# public key, but not the private key.
pk2.export_public(self.tname('keygen-pub2.pem'))
self.assertRaises(RSAUsageError, pk2.export_private,
self.tname('keygen-priv2.pem'))
def test_emit(self):
"""Basic sanity check on the code emitters."""
for key_size in RSA_KEY_SIZES:
k = RSA.generate(key_size=key_size)
pubpem = io.StringIO()
k.emit_public_pem(pubpem)
self.assertIn("BEGIN PUBLIC KEY", pubpem.getvalue())
self.assertIn("END PUBLIC KEY", pubpem.getvalue())
ccode = io.StringIO()
k.emit_c_public(ccode)
self.assertIn("rsa_pub_key", ccode.getvalue())
self.assertIn("rsa_pub_key_len", ccode.getvalue())
hashccode = io.StringIO()
k.emit_c_public_hash(hashccode)
self.assertIn("rsa_pub_key_hash", hashccode.getvalue())
self.assertIn("rsa_pub_key_hash_len", hashccode.getvalue())
rustcode = io.StringIO()
k.emit_rust_public(rustcode)
self.assertIn("RSA_PUB_KEY", rustcode.getvalue())
# raw data - bytes
pubraw = io.BytesIO()
k.emit_raw_public(pubraw)
self.assertTrue(len(pubraw.getvalue()) > 0)
hashraw = io.BytesIO()
k.emit_raw_public_hash(hashraw)
self.assertTrue(len(hashraw.getvalue()) > 0)
def test_emit_pub(self):
"""Basic sanity check on the code emitters, from public key."""
pubname = self.tname("public.pem")
for key_size in RSA_KEY_SIZES:
k = RSA.generate(key_size=key_size)
k.export_public(pubname)
k2 = load(pubname)
ccode = io.StringIO()
k2.emit_c_public(ccode)
self.assertIn("rsa_pub_key", ccode.getvalue())
self.assertIn("rsa_pub_key_len", ccode.getvalue())
rustcode = io.StringIO()
k2.emit_rust_public(rustcode)
self.assertIn("RSA_PUB_KEY", rustcode.getvalue())
def test_sig(self):
for key_size in RSA_KEY_SIZES:
k = RSA.generate(key_size=key_size)
buf = b'This is the message'
sig = k.sign(buf)
# The code doesn't have any verification, so verify this
# manually.
k.key.public_key().verify(
signature=sig,
data=buf,
padding=PSS(mgf=MGF1(SHA256()), salt_length=32),
algorithm=SHA256())
# Modify the message to make sure the signature fails.
self.assertRaises(InvalidSignature,
k.key.public_key().verify,
signature=sig,
data=b'This is thE message',
padding=PSS(mgf=MGF1(SHA256()), salt_length=32),
algorithm=SHA256())
if __name__ == '__main__':
unittest.main()