From 2d9a5afcd801837be7637048977982bd9e1330f5 Mon Sep 17 00:00:00 2001 From: Hans Date: Wed, 27 May 2015 16:46:24 +0200 Subject: ssh: Implement keyboard_interactive on server side --- lib/ssh/src/ssh.erl | 9 ++++ lib/ssh/src/ssh_auth.erl | 80 ++++++++++++++++++++++++++++++++++ lib/ssh/src/ssh_connection_handler.erl | 19 ++++++-- 3 files changed, 104 insertions(+), 4 deletions(-) (limited to 'lib/ssh/src') diff --git a/lib/ssh/src/ssh.erl b/lib/ssh/src/ssh.erl index 71e7d77475..7ed17618e7 100644 --- a/lib/ssh/src/ssh.erl +++ b/lib/ssh/src/ssh.erl @@ -331,6 +331,8 @@ handle_option([{exec, _} = Opt | Rest], SocketOptions, SshOptions) -> handle_option(Rest, SocketOptions, [handle_ssh_option(Opt) | SshOptions]); handle_option([{auth_methods, _} = Opt | Rest], SocketOptions, SshOptions) -> handle_option(Rest, SocketOptions, [handle_ssh_option(Opt) | SshOptions]); +handle_option([{auth_method_kb_interactive_data, _} = Opt | Rest], SocketOptions, SshOptions) -> + handle_option(Rest, SocketOptions, [handle_ssh_option(Opt) | SshOptions]); handle_option([{pref_public_key_algs, _} = Opt | Rest], SocketOptions, SshOptions) -> handle_option(Rest, SocketOptions, [handle_ssh_option(Opt) | SshOptions]); handle_option([{quiet_mode, _} = Opt|Rest], SocketOptions, SshOptions) -> @@ -411,6 +413,13 @@ handle_ssh_option({exec, Function} = Opt) when is_function(Function) -> Opt; handle_ssh_option({auth_methods, Value} = Opt) when is_list(Value) -> Opt; +handle_ssh_option({auth_method_kb_interactive_data, {Name,Instruction,Prompt,Echo}} = Opt) when is_list(Name), + is_list(Instruction), + is_list(Prompt), + is_boolean(Echo) -> + Opt; +handle_ssh_option({auth_method_kb_interactive_data, F} = Opt) when is_function(F,3) -> + Opt; handle_ssh_option({infofun, Value} = Opt) when is_function(Value) -> Opt; handle_ssh_option({connectfun, Value} = Opt) when is_function(Value) -> diff --git a/lib/ssh/src/ssh_auth.erl b/lib/ssh/src/ssh_auth.erl index 45c4d52d7e..9d1ab14ce9 100644 --- a/lib/ssh/src/ssh_auth.erl +++ b/lib/ssh/src/ssh_auth.erl @@ -257,6 +257,54 @@ handle_userauth_request(#ssh_msg_userauth_request{user = User, key_blob = KeyBlob}, Ssh)} end; +handle_userauth_request(#ssh_msg_userauth_request{user = User, + service = "ssh-connection", + method = "keyboard-interactive", + data = _}, + _, #ssh{opts = Opts} = Ssh) -> + %% RFC4256 + %% The data field contains: + %% - language tag (deprecated). If =/=[] SHOULD use it however. We skip + %% it for simplicity. + %% - submethods. "... the user can give a hint of which actual methods + %% he wants to use. ...". It's a "MAY use" so we skip + %% it. It also needs an understanding between the client + %% and the server. + %% + %% "The server MUST reply with an SSH_MSG_USERAUTH_SUCCESS, + %% SSH_MSG_USERAUTH_FAILURE, or SSH_MSG_USERAUTH_INFO_REQUEST message." + Default = {"SSH server", + "Enter password for \""++User++"\"", + "pwd: ", + false}, + + {Name, Instruction, Prompt, Echo} = + case proplists:get_value(auth_method_kb_interactive_data, Opts) of + undefined -> + Default; + {_,_,_,_}=V -> + V; + F when is_function(F) -> + {_,PeerName} = Ssh#ssh.peer, + F(PeerName, User, "ssh-connection") + end, + EchoEnc = case Echo of + true -> <>; + false -> <> + end, + Msg = #ssh_msg_userauth_info_request{name = unicode:characters_to_list(Name), + instruction = unicode:characters_to_list(Instruction), + language_tag = "", + num_prompts = 1, + data = <> + }, + {not_authorized, {User, undefined}, + ssh_transport:ssh_packet(Msg, Ssh#ssh{user = User, + opts = [{max_kb_tries,3},{kb_userauth_info_msg,Msg}|Opts] + })}; + handle_userauth_request(#ssh_msg_userauth_request{user = User, service = "ssh-connection", method = Other}, _, @@ -280,6 +328,38 @@ handle_userauth_info_request( #ssh_msg_userauth_info_response{num_responses = NumPrompts, data = Responses}, Ssh)}. +handle_userauth_info_response(#ssh_msg_userauth_info_response{num_responses = 1, + data = <>}, + #ssh{opts = Opts0, + user = User} = Ssh) -> + NumTriesLeft = proplists:get_value(max_kb_tries, Opts0, 0) - 1, + Opts = lists:keydelete(max_kb_tries,1,Opts0), + case check_password(User, unicode:characters_to_list(Password), Opts) of + true -> + {authorized, User, + ssh_transport:ssh_packet(#ssh_msg_userauth_success{}, Ssh)}; + false when NumTriesLeft > 0 -> + UserAuthInfoMsg = + (proplists:get_value(kb_userauth_info_msg,Opts)) + #ssh_msg_userauth_info_request{name = "", + instruction = + lists:concat( + ["Bad user or password, try again. ", + integer_to_list(NumTriesLeft), + " tries left."])}, + {not_authorized, {User, undefined}, + ssh_transport:ssh_packet(UserAuthInfoMsg, + Ssh#ssh{opts = [{max_kb_tries,NumTriesLeft}|Opts]})}; + + false -> + {not_authorized, {User, {error,"Bad user or password"}}, + ssh_transport:ssh_packet(#ssh_msg_userauth_failure{ + authentications = "", + partial_success = false}, + Ssh#ssh{opts = lists:keydelete(kb_userauth_info_msg,1,Opts)} + )} + end; + handle_userauth_info_response(#ssh_msg_userauth_info_response{}, _Auth) -> throw(#ssh_msg_disconnect{code = ?SSH_DISCONNECT_SERVICE_NOT_AVAILABLE, diff --git a/lib/ssh/src/ssh_connection_handler.erl b/lib/ssh/src/ssh_connection_handler.erl index 0f6162db60..3161c1f291 100644 --- a/lib/ssh/src/ssh_connection_handler.erl +++ b/lib/ssh/src/ssh_connection_handler.erl @@ -496,10 +496,21 @@ userauth(#ssh_msg_userauth_info_request{} = Msg, {next_state, userauth, next_packet(State#state{ssh_params = Ssh})}; userauth(#ssh_msg_userauth_info_response{} = Msg, - #state{ssh_params = #ssh{role = server} = Ssh0} = State) -> - {ok, {Reply, Ssh}} = ssh_auth:handle_userauth_info_response(Msg, Ssh0), - send_msg(Reply, State), - {next_state, userauth, next_packet(State#state{ssh_params = Ssh})}; + #state{ssh_params = #ssh{role = server, + peer = {_, Address}} = Ssh0, + opts = Opts, starter = Pid} = State) -> + case ssh_auth:handle_userauth_info_response(Msg, Ssh0) of + {authorized, User, {Reply, Ssh}} -> + send_msg(Reply, State), + Pid ! ssh_connected, + connected_fun(User, Address, "keyboard-interactive", Opts), + {next_state, connected, + next_packet(State#state{auth_user = User, ssh_params = Ssh})}; + {not_authorized, {User, Reason}, {Reply, Ssh}} -> + retry_fun(User, Address, Reason, Opts), + send_msg(Reply, State), + {next_state, userauth, next_packet(State#state{ssh_params = Ssh})} + end; userauth(#ssh_msg_userauth_success{}, #state{ssh_params = #ssh{role = client} = Ssh, starter = Pid} = State) -> -- cgit v1.2.3