rsa.py 1.1 KB

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  1. # Copyright 2017 Google LLC
  2. #
  3. # Licensed under the Apache License, Version 2.0 (the "License");
  4. # you may not use this file except in compliance with the License.
  5. # You may obtain a copy of the License at
  6. #
  7. # http://www.apache.org/licenses/LICENSE-2.0
  8. #
  9. # Unless required by applicable law or agreed to in writing, software
  10. # distributed under the License is distributed on an "AS IS" BASIS,
  11. # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. # See the License for the specific language governing permissions and
  13. # limitations under the License.
  14. """RSA cryptography signer and verifier."""
  15. try:
  16. # Prefer cryptograph-based RSA implementation.
  17. from google.auth.crypt import _cryptography_rsa
  18. RSASigner = _cryptography_rsa.RSASigner
  19. RSAVerifier = _cryptography_rsa.RSAVerifier
  20. except ImportError: # pragma: NO COVER
  21. # Fallback to pure-python RSA implementation if cryptography is
  22. # unavailable.
  23. from google.auth.crypt import _python_rsa
  24. RSASigner = _python_rsa.RSASigner # type: ignore
  25. RSAVerifier = _python_rsa.RSAVerifier # type: ignore