Merge branch 'hans/ssh/keyboard_interactive0/OTP-13255' into maint-18

* hans/ssh/keyboard_interactive0/OTP-13255:
  ssh: update vsn.mk to 4.2.1
  ssh: handle secondary ssh_msg_userauth_info_request message
  ssh: testcase for abnormal keyboard-interactive authentication

4 files changed, 86 insertions, 5 deletions

diff --git a/lib/ssh/src/ssh_auth.erl b/lib/ssh/src/ssh_auth.erl
index fdbb5c152a..b71bed033a 100644
--- a/lib/ssh/src/ssh_auth.erl
+++ b/lib/ssh/src/ssh_auth.erl
@@ -477,7 +477,7 @@ keyboard_interact_get_responses(_, undefined, Password, _, _, _, _, _,
 				1) when Password =/= undefined ->
     [Password]; %% Password auth implemented with keyboard-interaction and passwd is known
 keyboard_interact_get_responses(_, _, _, _, _, _, _, _, 0)  ->
-    [""];
+    [];
 keyboard_interact_get_responses(false, undefined, undefined, _, _, _, [Prompt|_], Opts, _) ->
     ssh_no_io:read_line(Prompt, Opts); %% Throws error as keyboard interaction is not allowed
 keyboard_interact_get_responses(true, undefined, _,IoCb, Name, Instr, PromptInfos, Opts, _) ->
diff --git a/lib/ssh/src/ssh_connection_handler.erl b/lib/ssh/src/ssh_connection_handler.erl
index f082db136c..ce1931e4f4 100644
--- a/lib/ssh/src/ssh_connection_handler.erl
+++ b/lib/ssh/src/ssh_connection_handler.erl
@@ -648,10 +648,12 @@ userauth_keyboard_interactive(Msg = #ssh_msg_userauth_failure{},
 userauth_keyboard_interactive_info_response(Msg=#ssh_msg_userauth_failure{},
 					    #state{ssh_params = #ssh{role = client}} = State) ->
     userauth(Msg, State);
-
 userauth_keyboard_interactive_info_response(Msg=#ssh_msg_userauth_success{},
 					    #state{ssh_params = #ssh{role = client}} = State) ->
-    userauth(Msg, State).
+    userauth(Msg, State);
+userauth_keyboard_interactive_info_response(Msg=#ssh_msg_userauth_info_request{},
+					    #state{ssh_params = #ssh{role = client}} = State) ->
+    userauth_keyboard_interactive(Msg, State).
 
 %%--------------------------------------------------------------------
 -spec connected({#ssh_msg_kexinit{}, binary()}, %%| %% #ssh_msg_kexdh_init{},
diff --git a/lib/ssh/test/ssh_protocol_SUITE.erl b/lib/ssh/test/ssh_protocol_SUITE.erl
index 5af60adfae..98a196d705 100644
--- a/lib/ssh/test/ssh_protocol_SUITE.erl
+++ b/lib/ssh/test/ssh_protocol_SUITE.erl
@@ -48,6 +48,7 @@ all() ->
     [{group,tool_tests},
      {group,kex},
      {group,service_requests},
+     {group,authentication},
      {group,packet_size_error},
      {group,field_size_error}
     ].
@@ -78,7 +79,9 @@ groups() ->
 			     bad_very_long_service_name,
 			     empty_service_name,
 			     bad_service_name_then_correct
-			    ]}
+			    ]},
+     {authentication, [], [client_handles_keyboard_interactive_0_pwds
+			  ]}
     ].
 
 
@@ -516,6 +519,82 @@ bad_service_name_length(Config, LengthExcess) ->
 	    receive_msg}
 	  ], InitialState).
     
+%%%--------------------------------------------------------------------
+%%% This is due to a fault report (OTP-13255) with OpenSSH-6.6.1
+client_handles_keyboard_interactive_0_pwds(Config) ->
+    {User,_Pwd} = server_user_password(Config),
+
+    %% Create a listening socket as server socket:
+    {ok,InitialState} = ssh_trpt_test_lib:exec(listen),
+    HostPort = ssh_trpt_test_lib:server_host_port(InitialState),
+
+    %% Start a process handling one connection on the server side:
+    spawn_link(
+      fun() ->
+	      {ok,_} =
+		  ssh_trpt_test_lib:exec(
+		    [{set_options, [print_ops, print_messages]},
+		     {accept, [{system_dir, system_dir(Config)},
+			       {user_dir, user_dir(Config)}]},
+		     receive_hello,
+		     {send, hello},
+
+		     {send, ssh_msg_kexinit},
+		     {match, #ssh_msg_kexinit{_='_'}, receive_msg},
+
+		     {match, #ssh_msg_kexdh_init{_='_'}, receive_msg},
+		     {send, ssh_msg_kexdh_reply},
+
+		     {send, #ssh_msg_newkeys{}},
+		     {match,  #ssh_msg_newkeys{_='_'}, receive_msg},
+
+		     {match, #ssh_msg_service_request{name="ssh-userauth"}, receive_msg},
+		     {send, #ssh_msg_service_accept{name="ssh-userauth"}},
+
+		     {match, #ssh_msg_userauth_request{service="ssh-connection",
+						       method="none",
+						       user=User,
+						       _='_'}, receive_msg},
+		     {send, #ssh_msg_userauth_failure{authentications = "keyboard-interactive",
+						      partial_success = false}},
+		     
+		     {match, #ssh_msg_userauth_request{service="ssh-connection",
+						       method="keyboard-interactive",
+						       user=User,
+						       _='_'}, receive_msg},
+		     {send, #ssh_msg_userauth_info_request{name = "",
+							   instruction = "",
+							   language_tag = "",
+							   num_prompts = 1,
+							   data = <<0,0,0,10,80,97,115,115,119,111,114,100,58,32,0>>
+							  }},
+		     {match, #ssh_msg_userauth_info_response{num_responses = 1,
+							     _='_'}, receive_msg},
+		      
+		     %% the next is strange, but openssh 6.6.1 does this and this is what this testcase is about
+		     {send, #ssh_msg_userauth_info_request{name = "",
+							   instruction = "",
+							   language_tag = "",
+							   num_prompts = 0,
+							   data = <<>>
+							  }},
+		     {match, #ssh_msg_userauth_info_response{num_responses = 0,
+							     data = <<>>,
+							     _='_'}, receive_msg},
+		     %% Here we know that the tested fault is fixed
+		     {send, #ssh_msg_userauth_success{}},
+		     close_socket,
+		     print_state
+		    ],
+		    InitialState)
+      end),
+
+    %% and finally connect to it with a regular Erlang SSH client:
+    {ok,_} = std_connect(HostPort, Config, 
+			 [{preferred_algorithms,[{kex,['diffie-hellman-group1-sha1']}]}]
+			).
+
+
 %%%================================================================
 %%%==== Internal functions ========================================
 %%%================================================================
diff --git a/lib/ssh/vsn.mk b/lib/ssh/vsn.mk
index 25b19133b1..55d12abffe 100644
--- a/lib/ssh/vsn.mk
+++ b/lib/ssh/vsn.mk
@@ -1,5 +1,5 @@
 #-*-makefile-*-   ; force emacs to enter makefile-mode
 
-SSH_VSN = 4.2
+SSH_VSN = 4.2.1
 
 APP_VSN    = "ssh-$(SSH_VSN)"