pyOpenSSL -- A Python wrapper around the OpenSSL library

Note: The Python Cryptographic Authority strongly suggests the use of pyca/cryptography where possible. If you are using pyOpenSSL for anything other than making a TLS connection you should move to cryptography and drop your pyOpenSSL dependency.

High-level wrapper around a subset of the OpenSSL library. Includes

• SSL.Connection objects, wrapping the methods of Python's portable sockets
• Callbacks written in Python
• Extensive error-handling mechanism, mirroring OpenSSL's error codes

... and much more.

You can find more information in the documentation. Development takes place on GitHub.

Discussion

If you run into bugs, you can file them in our issue tracker.

We maintain a cryptography-dev mailing list for both user and development discussions.

You can also join #pyca on irc.libera.chat to ask questions or get involved.

Release Information

23.2.0 (2023-05-30)

Backward-incompatible changes:

• Removed X509StoreFlags.NOTIFY_POLICY. #1213.

Deprecations:

Changes:

• cryptography maximum version has been increased to 41.0.x.
• Invalid versions are now rejected in OpenSSL.crypto.X509Req.set_version.
• Added X509VerificationCodes to OpenSSL.SSL. #1202.

23.1.1 (2023-03-28)

Backward-incompatible changes:

Deprecations:

Changes:

• Worked around an issue in OpenSSL 3.1.0 which caused X509Extension.get_short_name to raise an exception when no short name was known to OpenSSL. #1204.

23.1.0 (2023-03-24)

Backward-incompatible changes:

Deprecations:

Changes:

• cryptography maximum version has been increased to 40.0.x.
• Add OpenSSL.SSL.Connection.DTLSv1_get_timeout and OpenSSL.SSL.Connection.DTLSv1_handle_timeout to support DTLS timeouts #1180.

23.0.0 (2023-01-01)

Backward-incompatible changes:

Deprecations:

Changes:

• Add OpenSSL.SSL.X509StoreFlags.PARTIAL_CHAIN constant to allow for users to perform certificate verification on partial certificate chains. #1166
• cryptography maximum version has been increased to 39.0.x.

22.1.0 (2022-09-25)

Backward-incompatible changes:

• Remove support for SSLv2 and SSLv3.
• The minimum cryptography version is now 38.0.x (and we now pin releases against cryptography major versions to prevent future breakage)
• The OpenSSL.crypto.X509StoreContextError exception has been refactored, changing its internal attributes. #1133

Deprecations:

• OpenSSL.SSL.SSLeay_version is deprecated in favor of OpenSSL.SSL.OpenSSL_version. The constants OpenSSL.SSL.SSLEAY_* are deprecated in favor of OpenSSL.SSL.OPENSSL_*.

Changes:

• Add OpenSSL.SSL.Connection.set_verify and OpenSSL.SSL.Connection.get_verify_mode to override the context object's verification flags. #1073
• Add OpenSSL.SSL.Connection.use_certificate and OpenSSL.SSL.Connection.use_privatekey to set a certificate per connection (and not just per context) #1121.

22.0.0 (2022-01-29)

Backward-incompatible changes:

• Drop support for Python 2.7. #1047
• The minimum cryptography version is now 35.0.

Deprecations:

Changes:

• Expose wrappers for some DTLS primitives. #1026

21.0.0 (2021-09-28)

Backward-incompatible changes:

• The minimum cryptography version is now 3.3.
• Drop support for Python 3.5

Deprecations:

Changes:

• Raise an error when an invalid ALPN value is set. #993
• Added OpenSSL.SSL.Context.set_min_proto_version and OpenSSL.SSL.Context.set_max_proto_version to set the minimum and maximum supported TLS version #985.
• Updated to_cryptography and from_cryptography methods to support an upcoming release of cryptography without raising deprecation warnings. #1030

20.0.1 (2020-12-15)

Backward-incompatible changes:

Deprecations:

Changes:

• Fixed compatibility with OpenSSL 1.1.0.

20.0.0 (2020-11-27)

Backward-incompatible changes:

• The minimum cryptography version is now 3.2.
• Remove deprecated OpenSSL.tsafe module.
• Removed deprecated OpenSSL.SSL.Context.set_npn_advertise_callback, OpenSSL.SSL.Context.set_npn_select_callback, and OpenSSL.SSL.Connection.get_next_proto_negotiated.
• Drop support for Python 3.4
• Drop support for OpenSSL 1.0.1 and 1.0.2

Deprecations:

• Deprecated OpenSSL.crypto.loads_pkcs7 and OpenSSL.crypto.loads_pkcs12.

Changes:

• Added a new optional chain parameter to OpenSSL.crypto.X509StoreContext() where additional untrusted certificates can be specified to help chain building. #948
• Added OpenSSL.crypto.X509Store.load_locations to set trusted certificate file bundles and/or directories for verification. #943
• Added Context.set_keylog_callback to log key material. #910
• Added OpenSSL.SSL.Connection.get_verified_chain to retrieve the verified certificate chain of the peer. #894.
• Make verification callback optional in Context.set_verify. If omitted, OpenSSL's default verification is used. #933
• Fixed a bug that could truncate or cause a zero-length key error due to a null byte in private key passphrase in OpenSSL.crypto.load_privatekey and OpenSSL.crypto.dump_privatekey. #947

19.1.0 (2019-11-18)

Backward-incompatible changes:

• Removed deprecated ContextType, ConnectionType, PKeyType, X509NameType, X509ReqType, X509Type, X509StoreType, CRLType, PKCS7Type, PKCS12Type, and NetscapeSPKIType aliases. Use the classes without the Type suffix instead. #814
• The minimum cryptography version is now 2.8 due to issues on macOS with a transitive dependency. #875

Deprecations:

• Deprecated OpenSSL.SSL.Context.set_npn_advertise_callback, OpenSSL.SSL.Context.set_npn_select_callback, and OpenSSL.SSL.Connection.get_next_proto_negotiated. ALPN should be used instead. #820

Changes:

• Support bytearray in SSL.Connection.send() by using cffi's from_buffer. #852
• The OpenSSL.SSL.Context.set_alpn_select_callback can return a new NO_OVERLAPPING_PROTOCOLS sentinel value to allow a TLS handshake to complete without an application protocol.

Full changelog.