blob: af54c6461d93985d1f6093fd7e05631f12495a27 [file] [log] [blame]
# Copyright 2020 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS-IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""A command-line utility for testing PublicKeySign primitives.
It requires 3 arguments:
keyset-file: name of the file with the keyset to be used for signing
message-file: name of the file that contains message to be signed
output-file: name of the output file for the resulting plaintext
"""
from __future__ import absolute_import
from __future__ import division
# Placeholder for import for type annotations
from __future__ import print_function
# Special imports
from absl import app
from absl import flags
from absl import logging
import tink
from tink import cleartext_keyset_handle
from tink import signature
FLAGS = flags.FLAGS
def read_keyset(keyset_filename):
"""Load a keyset from a file.
Args:
keyset_filename: A path to a keyset file
Returns:
A KeysetHandle of the file's keyset
Raises:
TinkError: if the file is not valid
IOError: if the file does not exist
"""
with open(keyset_filename, 'rb') as keyset_file:
text = keyset_file.read()
keyset = cleartext_keyset_handle.read(tink.BinaryKeysetReader(text))
return keyset
def main(argv):
if len(argv) != 4:
raise app.UsageError(
'Expected 3 arguments, got %d.\n'
'Usage: %s keyset-file message-file output-file' %
(len(argv) - 1, argv[0]))
keyset_filename = argv[1]
message_filename = argv[2]
output_filename = argv[3]
logging.info(
'Using keyset from file %s to sign %s file.\n'
'The signature will be written to file %s\n',
keyset_filename, message_filename, output_filename)
# Initialise Tink
try:
signature.register()
except tink.TinkError as e:
logging.error('Error initialising Tink: %s', e)
return 1
# Read the keyset into keyset_handle
try:
keyset_handle = read_keyset(keyset_filename)
except tink.TinkError as e:
logging.error('Error reading key: %s', e)
return 1
# Get the primitive
try:
sign_primitive = keyset_handle.primitive(signature.PublicKeySign)
except tink.TinkError as e:
logging.error('Error creating primitive: %s', e)
return 1
# Read the message
with open(message_filename, 'rb') as message_file:
message_data = message_file.read()
try:
signature_data = sign_primitive.sign(message_data)
except tink.TinkError as e:
logging.error('Error signing the message: %s', e)
return 1
with open(output_filename, 'wb') as output_file:
output_file.write(signature_data)
logging.info('All done.')
if __name__ == '__main__':
app.run(main)