From 995f42028bfbb939572840b7a0a38c1c39ba05fa Mon Sep 17 00:00:00 2001 From: Ingela Anderton Andin Date: Thu, 25 Mar 2010 15:50:24 +0000 Subject: OTP-7046 Support for Diffie-Hellman keyexchange --- lib/ssl/src/ssl_handshake.erl | 159 ++++++++++++++++++++++++------------------ 1 file changed, 90 insertions(+), 69 deletions(-) (limited to 'lib/ssl/src/ssl_handshake.erl') diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl index 4e1c495fda..ff78375b9f 100644 --- a/lib/ssl/src/ssl_handshake.erl +++ b/lib/ssl/src/ssl_handshake.erl @@ -35,7 +35,7 @@ hello_request/0, certify/5, certificate/3, client_certificate_verify/6, certificate_verify/6, certificate_request/2, - key_exchange/2, finished/4, + key_exchange/2, server_key_exchange_hash/2, finished/4, verify_connection/5, get_tls_handshake/4, server_hello_done/0, sig_alg/1, @@ -257,8 +257,10 @@ client_certificate_verify(OwnCert, MasterSecret, Version, Algorithm, %% Description: Checks that the certificate_verify message is valid. %%-------------------------------------------------------------------- certificate_verify(Signature, {_, PublicKey, _}, Version, - MasterSecret, Algorithm, {_, Hashes0}) - when Algorithm =:= rsa; Algorithm =:= dh_rsa; Algorithm =:= dhe_rsa -> + MasterSecret, Algorithm, {_, Hashes0}) + when Algorithm == rsa; + Algorithm == dh_rsa; + Algorithm == dhe_rsa -> Hashes = calc_certificate_verify(Version, MasterSecret, Algorithm, Hashes0), case public_key:decrypt_public(Signature, PublicKey, @@ -305,30 +307,32 @@ key_exchange(client, fixed_diffie_hellman) -> #client_diffie_hellman_public{ dh_public = <<>> }}; -key_exchange(client, {dh, PublicKey}) -> - Len = byte_size(PublicKey), +key_exchange(client, {dh, <>}) -> #client_key_exchange{ - exchange_keys = #client_diffie_hellman_public{ - dh_public = <>} + exchange_keys = #client_diffie_hellman_public{ + dh_public = PublicKey} }; -%% key_exchange(server, {{?'dhpublicnumber', _PublicKey, -%% #'DomainParameters'{p = P, g = G, y = Y}, -%% SignAlgorithm, ClientRandom, ServerRandom}}) -> -%% ServerDHParams = #server_dh_params{dh_p = P, dh_g = G, dh_y = Y}, -%% PLen = byte_size(P), -%% GLen = byte_size(G), -%% YLen = byte_size(Y), -%% Hash = server_key_exchange_hash(SignAlgorithm, <>), -%% Signed = digitally_signed(Hash, PrivateKey), -%% #server_key_exchange{ -%% params = ServerDHParams, -%% signed_params = Signed -%% }; +key_exchange(server, {dh, {<>, _}, + #'DHParameter'{prime = P, base = G}, + KeyAlgo, ClientRandom, ServerRandom, PrivateKey}) -> + <> = crypto:mpint(P), + <> = crypto:mpint(G), + PLen = byte_size(PBin), + GLen = byte_size(GBin), + YLen = byte_size(PublicKey), + ServerDHParams = #server_dh_params{dh_p = PBin, + dh_g = GBin, dh_y = PublicKey}, + + Hash = + server_key_exchange_hash(KeyAlgo, <>), + Signed = digitally_signed(Hash, PrivateKey), + #server_key_exchange{params = ServerDHParams, + signed_params = Signed}; key_exchange(_, _) -> %%TODO : Real imp #server_key_exchange{}. @@ -426,7 +430,8 @@ server_hello_done() -> %% %% encode a handshake packet to binary %%-------------------------------------------------------------------- -encode_handshake(Package, Version, SigAlg) -> +encode_handshake(Package, Version, KeyAlg) -> + SigAlg = sig_alg(KeyAlg), {MsgType, Bin} = enc_hs(Package, Version, SigAlg), Len = byte_size(Bin), [MsgType, ?uint24(Len), Bin]. @@ -446,31 +451,15 @@ get_tls_handshake(Data, Buffer, KeyAlg, Version) -> get_tls_handshake_aux(list_to_binary([Buffer, Data]), KeyAlg, Version, []). -get_tls_handshake_aux(<>, - KeyAlg, Version, Acc) -> +get_tls_handshake_aux(<>, KeyAlg, + Version, Acc) -> Raw = <>, - H = dec_hs(Type, Body, KeyAlg, Version), + H = dec_hs(Type, Body, key_excahange_alg(KeyAlg), Version), get_tls_handshake_aux(Rest, KeyAlg, Version, [{H,Raw} | Acc]); get_tls_handshake_aux(Data, _KeyAlg, _Version, Acc) -> {lists:reverse(Acc), Data}. -%%-------------------------------------------------------------------- -%% Function: sig_alg(atom()) -> integer() -%% -%% Description: Convert from key exchange as atom to signature -%% algorithm as a ?SIGNATURE_... constant -%%-------------------------------------------------------------------- - -sig_alg(dh_anon) -> - ?SIGNATURE_ANONYMOUS; -sig_alg(Alg) when Alg == dhe_rsa; Alg == rsa; Alg == dh_rsa -> - ?SIGNATURE_RSA; -sig_alg(Alg) when Alg == dh_dss; Alg == dhe_dss -> - ?SIGNATURE_DSA; -sig_alg(_) -> - ?NULL. - - %%-------------------------------------------------------------------- %%% Internal functions %%-------------------------------------------------------------------- @@ -658,8 +647,8 @@ dec_hs(?SERVER_HELLO, <>, _, _) -> #certificate{asn1_certificates = certs_to_list(ASN1Certs)}; dec_hs(?SERVER_KEY_EXCHANGE, <>, + ?UINT16(ExpLen), Exp:ExpLen/binary, + ?UINT16(_), Sig/binary>>, ?KEY_EXCHANGE_RSA, _) -> #server_key_exchange{params = #server_rsa_params{rsa_modulus = Mod, rsa_exponent = Exp}, @@ -667,9 +656,10 @@ dec_hs(?SERVER_KEY_EXCHANGE, <>, + ?UINT16(_), Sig/binary>>, ?KEY_EXCHANGE_DIFFIE_HELLMAN, _) -> - #server_key_exchange{params = #server_dh_params{dh_p = P,dh_g = G, dh_y = Y}, + #server_key_exchange{params = #server_dh_params{dh_p = P,dh_g = G, + dh_y = Y}, signed_params = Sig}; dec_hs(?CERTIFICATE_REQUEST, <>, _, _) -> #server_hello_done{}; dec_hs(?CERTIFICATE_VERIFY,<>, _, _)-> #certificate_verify{signature = Signature}; -dec_hs(?CLIENT_KEY_EXCHANGE, PKEPMS, rsa, {3, 0}) -> +dec_hs(?CLIENT_KEY_EXCHANGE, PKEPMS, ?KEY_EXCHANGE_RSA, {3, 0}) -> PreSecret = #encrypted_premaster_secret{premaster_secret = PKEPMS}, #client_key_exchange{exchange_keys = PreSecret}; -dec_hs(?CLIENT_KEY_EXCHANGE, <>, rsa, _) -> +dec_hs(?CLIENT_KEY_EXCHANGE, <>, + ?KEY_EXCHANGE_RSA, _) -> PreSecret = #encrypted_premaster_secret{premaster_secret = PKEPMS}, #client_key_exchange{exchange_keys = PreSecret}; dec_hs(?CLIENT_KEY_EXCHANGE, <<>>, ?KEY_EXCHANGE_DIFFIE_HELLMAN, _) -> %% TODO: Should check whether the cert already contains a suitable DH-key (7.4.7.2) throw(?ALERT_REC(?FATAL, implicit_public_value_encoding)); -dec_hs(?CLIENT_KEY_EXCHANGE, <>, +dec_hs(?CLIENT_KEY_EXCHANGE, <>, ?KEY_EXCHANGE_DIFFIE_HELLMAN, _) -> - #client_diffie_hellman_public{dh_public = DH_YC}; + #client_key_exchange{exchange_keys = + #client_diffie_hellman_public{dh_public = DH_Y}}; dec_hs(?FINISHED, VerifyData, _, _) -> #finished{verify_data = VerifyData}; dec_hs(_, _, _, _) -> @@ -765,12 +757,13 @@ enc_hs(#certificate{asn1_certificates = ASN1CertList}, _Version, _) -> {?CERTIFICATE, <>}; enc_hs(#server_key_exchange{params = #server_rsa_params{rsa_modulus = Mod, rsa_exponent = Exp}, - signed_params = SignedParams}, _Version, _) -> + signed_params = SignedParams}, _Version, _) -> ModLen = byte_size(Mod), ExpLen = byte_size(Exp), - {?SERVER_KEY_EXCHANGE, <> + ?UINT16(SignedLen), SignedParams/binary>> }; enc_hs(#server_key_exchange{params = #server_dh_params{ dh_p = P, dh_g = G, dh_y = Y}, @@ -778,10 +771,11 @@ enc_hs(#server_key_exchange{params = #server_dh_params{ PLen = byte_size(P), GLen = byte_size(G), YLen = byte_size(Y), - {?SERVER_KEY_EXCHANGE, <> + SignedLen = byte_size(SignedParams), + {?SERVER_KEY_EXCHANGE, <> }; enc_hs(#certificate_request{certificate_types = CertTypes, certificate_authorities = CertAuths}, @@ -936,13 +930,40 @@ calc_certificate_verify({3, N}, _, Algorithm, Hashes) when N == 1; N == 2 -> ssl_tls1:certificate_verify(Algorithm, Hashes). -%% server_key_exchange_hash(Algorithm, Value) when Algorithm == rsa; -%% Algorithm == dh_rsa; -%% Algorithm == dhe_rsa -> -%% MD5 = crypto:md5_final(Value), -%% SHA = crypto:sha_final(Value), -%% <>; +server_key_exchange_hash(Algorithm, Value) when Algorithm == rsa; + Algorithm == dh_rsa; + Algorithm == dhe_rsa -> + MD5Context = crypto:md5_init(), + NewMD5Context = crypto:md5_update(MD5Context, Value), + MD5 = crypto:md5_final(NewMD5Context), + + SHAContext = crypto:sha_init(), + NewSHAContext = crypto:sha_update(SHAContext, Value), + SHA = crypto:sha_final(NewSHAContext), + + <>; + +server_key_exchange_hash(Algorithm, Value) when Algorithm == dh_dss; + Algorithm == dhe_dss -> + + SHAContext = crypto:sha_init(), + NewSHAContext = crypto:sha_update(SHAContext, Value), + crypto:sha_final(NewSHAContext). + + +sig_alg(dh_anon) -> + ?SIGNATURE_ANONYMOUS; +sig_alg(Alg) when Alg == dhe_rsa; Alg == rsa; Alg == dh_rsa -> + ?SIGNATURE_RSA; +sig_alg(Alg) when Alg == dh_dss; Alg == dhe_dss -> + ?SIGNATURE_DSA; +sig_alg(_) -> + ?NULL. -%% server_key_exchange_hash(Algorithm, Value) when Algorithm == dh_dss; -%% Algorithm == dhe_dss -> -%% crypto:sha_final(Value). +key_excahange_alg(rsa) -> + ?KEY_EXCHANGE_RSA; +key_excahange_alg(Alg) when Alg == dhe_rsa; Alg == dhe_dss; + Alg == dh_dss; Alg == dh_rsa; Alg == dh_anon -> + ?KEY_EXCHANGE_DIFFIE_HELLMAN; +key_excahange_alg(_) -> + ?NULL. -- cgit v1.2.3