From 9b9d1cfa157134d8b14aaa2de5b36db28cb8b17a Mon Sep 17 00:00:00 2001 From: Hans Nilsson Date: Wed, 25 Nov 2015 20:02:36 +0100 Subject: ssh: implemented server side SSH_MSG_KEX_DH_GEX_REQUEST_OLD for putty client --- lib/ssh/src/ssh_transport.erl | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'lib/ssh/src/ssh_transport.erl') diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl index 2b6f0a3cdc..1fbe50e758 100644 --- a/lib/ssh/src/ssh_transport.erl +++ b/lib/ssh/src/ssh_transport.erl @@ -427,6 +427,32 @@ handle_kex_dh_gex_request(#ssh_msg_kex_dh_gex_request{min = Min, Ssh#ssh{keyex_key = {{Private, Public}, {G, P}}, keyex_info = {Min, Max, NBits} }}; + +handle_kex_dh_gex_request(#ssh_msg_kex_dh_gex_request_old{n = NBits}, + Ssh0=#ssh{opts=Opts}) -> + %% server + %% + %% This message was in the draft-00 of rfc4419 + %% (https://tools.ietf.org/html/draft-ietf-secsh-dh-group-exchange-00) + %% In later drafts and the rfc is "is used for backward compatibility". + %% Unfortunatly the rfc does not specify how to treat the parameter n + %% if there is no group of that modulus length :( + %% The draft-00 however specifies that n is the "... number of bits + %% the subgroup should have at least". + %% Further, it says that "Servers and clients SHOULD support groups + %% with a modulus length of k bits, where 1024 <= k <= 8192." + %% + Min = NBits, + Max = 8192, + {G, P} = dh_gex_group(Min, NBits, Max, proplists:get_value(dh_gex_groups,Opts)), + {Public, Private} = generate_key(dh, [P,G]), + {SshPacket, Ssh} = + ssh_packet(#ssh_msg_kex_dh_gex_group{p = P, g = G}, Ssh0), + {ok, SshPacket, + Ssh#ssh{keyex_key = {{Private, Public}, {G, P}}, + keyex_info = {-1, -1, NBits} % flag for kex_h hash calc + }}; + handle_kex_dh_gex_request(_, _) -> throw({{error,bad_ssh_msg_kex_dh_gex_request}, #ssh_msg_disconnect{ @@ -1286,6 +1312,9 @@ kex_h(SSH, Curve, Key, Q_c, Q_s, K) -> kex_h(SSH, Key, Min, NBits, Max, Prime, Gen, E, F, K) -> L = if Min==-1; Max==-1 -> + %% flag from 'ssh_msg_kex_dh_gex_request_old' + %% It was like this before that message was supported, + %% why? Ts = [string,string,binary,binary,binary, uint32, mpint,mpint,mpint,mpint,mpint], -- cgit v1.2.3