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2017-11-16ssl: Align code of TLS/DTLS record handlingIngela Anderton Andin
2017-05-04Update copyright yearRaimo Niskanen
2017-04-21ssl: TLS-1.2 clients will now always send hello messages on its own format.Ingela Anderton Andin
Note this is a change form how it works for earlier versions that will send the first hello message on the lowest supported version. From RFC 5246 Appendix E. Backward Compatibility E.1. Compatibility with TLS 1.0/1.1 and SSL 3.0 Since there are various versions of TLS (1.0, 1.1, 1.2, and any future versions) and SSL (2.0 and 3.0), means are needed to negotiate the specific protocol version to use. The TLS protocol provides a built-in mechanism for version negotiation so as not to bother other protocol components with the complexities of version selection. TLS versions 1.0, 1.1, and 1.2, and SSL 3.0 are very similar, and use compatible ClientHello messages; thus, supporting all of them is relatively easy. Similarly, servers can easily handle clients trying to use future versions of TLS as long as the ClientHello format remains compatible, and the client supports the highest protocol version available in the server. A TLS 1.2 client who wishes to negotiate with such older servers will send a normal TLS 1.2 ClientHello, containing { 3, 3 } (TLS 1.2) in ClientHello.client_version. If the server does not support this version, it will respond with a ServerHello containing an older version number. If the client agrees to use this version, the negotiation will proceed as appropriate for the negotiated protocol. If the version chosen by the server is not supported by the client (or not acceptable), the client MUST send a "protocol_version" alert message and close the connection. If a TLS server receives a ClientHello containing a version number greater than the highest version supported by the server, it MUST reply according to the highest version supported by the server. A TLS server can also receive a ClientHello containing a version number smaller than the highest supported version. If the server wishes to negotiate with old clients, it will proceed as appropriate for the highest version supported by the server that is not greater than ClientHello.client_version. For example, if the server supports TLS 1.0, 1.1, and 1.2, and client_version is TLS 1.0, the server will proceed with a TLS 1.0 ServerHello. If server supports (or is willing to use) only versions greater than client_version, it MUST send a "protocol_version" alert message and close the connection. Whenever a client already knows the highest protocol version known to a server (for example, when resuming a session), it SHOULD initiate the connection in that native protocol. Note: some server implementations are known to implement version negotiation incorrectly. For example, there are buggy TLS 1.0 servers that simply close the connection when the client offers a version newer than TLS 1.0. Also, it is known that some servers will refuse the connection if any TLS extensions are included in ClientHello. Interoperability with such buggy servers is a complex topic beyond the scope of this document, and may require multiple connection attempts by the client. Earlier versions of the TLS specification were not fully clear on what the record layer version number (TLSPlaintext.version) should contain when sending ClientHello (i.e., before it is known which version of the protocol will be employed). Thus, TLS servers compliant with this specification MUST accept any value {03,XX} as the record layer version number for ClientHello. TLS clients that wish to negotiate with older servers MAY send any value {03,XX} as the record layer version number. Typical values would be {03,00}, the lowest version number supported by the client, and the value of ClientHello.client_version. No single value will guarantee interoperability with all old servers, but this is a complex topic beyond the scope of this document.
2017-04-13ssl, dtls: Refactor so that DTLS records are handled correctly together with ↵Ingela Anderton Andin
AEAD handling
2016-12-07Update copyright-yearErlang/OTP
2016-12-05ssl: Implement DTLS state machineIngela Anderton Andin
Beta DTLS, not production ready. Only very basically tested, and not everything in the SPEC is implemented and some things are hard coded that should not be, so this implementation can not be consider secure. Refactor "TLS connection state" and socket handling, to facilitate DTLS implementation. Create dtls "listner" (multiplexor) process that spawns DTLS connection process handlers. Handle DTLS fragmentation. Framework for handling retransmissions. Replay Detection is not implemented yet. Alerts currently always handled as in TLS.
2016-09-05ssl: Refactor to use maps for the connection statesIngela Anderton Andin
2015-12-08ssl: Correct specIngela Anderton Andin
2015-11-18ssl: Client should send the hello message in the lowest version it is ↵Ingela Anderton Andin
willing to support Refactor highest_protocol_version so that code is symmetrical with lowest_protocol_version. For clarity and possible future use cases of highest_protocol_version/2
2015-06-18Change license text to APLv2Bruce Yinhe
2015-03-05Merge branch 'maint'Ingela Anderton Andin
Conflicts: lib/ssl/src/ssl_cipher.erl lib/ssl/test/ssl_basic_SUITE.erl
2015-03-02ssl: Implement support for TLS_FALLBACK_SCSVIngela Anderton Andin
2015-01-23ssl: Reenable padding check for TLS-1.0 and provide backwards compatibleIngela Anderton Andin
disable option
2015-01-23ssl: Remove sslv3 from the default supported protocol versionsIngela Anderton Andin
2015-01-23ssl: Reenable padding check for TLS-1.0 and provide backwards compatibleIngela Anderton Andin
disable option Conflicts: lib/ssl/src/ssl_cipher.erl lib/ssl/src/ssl_record.erl lib/ssl/src/tls_record.erl lib/ssl/test/ssl_cipher_SUITE.erl
2014-09-03ssl: implement AES128-GCM suitesAndreas Schultz
2014-04-17ssl: Correct decryption error handlingIngela Anderton Andin
2014-03-25ssl: Improve type specsIngela Anderton Andin
Conflicts: lib/ssl/src/dtls_record.erl
2014-02-14Fix edoc usage errorsPierre Fenoll
Errors discovered using `erldocs`: Superfluous @hidden tag would exit edoc application; 'Multiple @spec tag': appended a @clear tag after macro condition; '@spec arity does not match': added missing argument.
2013-12-02ssl: Refactor handshake and record handlingIngela Anderton Andin
2013-09-10ssl: Refactor TLS/DTLS record handlingIngela Anderton Andin
2013-09-10ssl: DTLS record handlingIngela Anderton Andin
Also refactor so that TLS and DTLS can have common functions when possible.
2013-06-04ssl: Structural perarparation to support DTLSIngela Anderton Andin
Also phase in tls module as main API instead of ssl. To make API clearer. As TLS is the new protocol name. Maybe keep some API functions in ssl