From 2fe9ed0b1171aadc87e2bed6990a9857bee55345 Mon Sep 17 00:00:00 2001 From: Ingela Anderton Andin Date: Thu, 31 Jul 2014 15:21:52 +0200 Subject: ssl: Correct handling of certificate_types in Certificate Requests FROM TLS 1.2 RFC: The interaction of the certificate_types and supported_signature_algorithms fields is somewhat complicated. certificate_types has been present in TLS since SSLv3, but was somewhat underspecified. Much of its functionality is superseded by supported_signature_algorithms. The following rules apply: - Any certificates provided by the client MUST be signed using a hash/signature algorithm pair found in supported_signature_algorithms. - The end-entity certificate provided by the client MUST contain a key that is compatible with certificate_types. If the key is a signature key, it MUST be usable with some hash/signature algorithm pair in supported_signature_algorithms. - For historical reasons, the names of some client certificate types include the algorithm used to sign the certificate. For example, in earlier versions of TLS, rsa_fixed_dh meant a certificate signed with RSA and containing a static DH key. In TLS 1.2, this functionality has been obsoleted by the supported_signature_algorithms, and the certificate type no longer restricts the algorithm used to sign the certificate. For example, if the server sends dss_fixed_dh certificate type and {{sha1, dsa}, {sha1, rsa}} signature types, the client MAY reply with a certificate containing a static DH key, signed with RSA- SHA1. --- lib/ssl/src/ssl_handshake.erl | 34 +++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-) (limited to 'lib/ssl/src') diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl index b018332df1..25bdc5ef93 100644 --- a/lib/ssl/src/ssl_handshake.erl +++ b/lib/ssl/src/ssl_handshake.erl @@ -207,7 +207,7 @@ client_certificate_verify(OwnCert, MasterSecret, Version, %% Description: Creates a certificate_request message, called by the server. %%-------------------------------------------------------------------- certificate_request(CipherSuite, CertDbHandle, CertDbRef, Version) -> - Types = certificate_types(CipherSuite), + Types = certificate_types(ssl_cipher:suite_definition(CipherSuite), Version), HashSigns = advertised_hash_signs(Version), Authorities = certificate_authorities(CertDbHandle, CertDbRef), #certificate_request{ @@ -1098,19 +1098,31 @@ supported_ecc(_) -> %%-------------certificate handling -------------------------------- -certificate_types({KeyExchange, _, _, _}) - when KeyExchange == rsa; - KeyExchange == dhe_dss; - KeyExchange == dhe_rsa; - KeyExchange == ecdhe_rsa -> - <>; +certificate_types(_, {N, M}) when N >= 3 andalso M >= 3 -> + case proplists:get_bool(ecdsa, + proplists:get_value(public_keys, crypto:supports())) of + true -> + <>; + false -> + <> + end; + +certificate_types({KeyExchange, _, _, _}, _) when KeyExchange == rsa; + KeyExchange == dhe_rsa; + KeyExchange == ecdhe_rsa -> + <>; + +certificate_types({KeyExchange, _, _, _}, _) when KeyExchange == dhe_dss, + KeyExchange == srp_dss -> + <>; -certificate_types({KeyExchange, _, _, _}) - when KeyExchange == dh_ecdsa; - KeyExchange == dhe_ecdsa -> +certificate_types({KeyExchange, _, _, _}, _) when KeyExchange == dh_ecdsa; + KeyExchange == dhe_ecdsa; + KeyExchange == ecdh_ecdsa; + KeyExchange == ecdhe_ecdsa -> <>; -certificate_types(_) -> +certificate_types(_, _) -> <>. certificate_authorities(CertDbHandle, CertDbRef) -> -- cgit v1.2.3