From 979b94a3f31697fe06f329660f2ea9e48944490a Mon Sep 17 00:00:00 2001 From: Hans Date: Tue, 26 May 2015 19:23:04 +0200 Subject: ssh: Set max num algoritms in msg_kexinit negotiation This is to prevent some dos-attac scenarios. The limit is hard-coded. --- lib/ssh/src/ssh_transport.erl | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (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 8669be570e..34b76f1b08 100644 --- a/lib/ssh/src/ssh_transport.erl +++ b/lib/ssh/src/ssh_transport.erl @@ -519,10 +519,15 @@ alg_final(SSH0) -> {ok,SSH6} = decompress_final(SSH5), SSH6. -select_all(CL, SL) -> +select_all(CL, SL) when length(CL) + length(SL) < 50 -> A = CL -- SL, %% algortihms only used by client %% algorithms used by client and server (client pref) - lists:map(fun(ALG) -> list_to_atom(ALG) end, (CL -- A)). + lists:map(fun(ALG) -> list_to_atom(ALG) end, (CL -- A)); +select_all(_CL, _SL) -> + throw(#ssh_msg_disconnect{code = ?SSH_DISCONNECT_PROTOCOL_ERROR, + description = "Too many algorithms", + language = "en"}). + select([], []) -> none; -- cgit v1.2.3