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path: root/lib/ssh/test/ssh_to_openssh_SUITE.erl
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%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2008-2016. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%%     http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%

%%
-module(ssh_to_openssh_SUITE).

-include_lib("common_test/include/ct.hrl").
-include("ssh_test_lib.hrl").

%% Note: This directive should only be used in test suites.
-compile(export_all).

-define(TIMEOUT, 50000).
-define(SSH_DEFAULT_PORT, 22).
-define(REKEY_DATA_TMO, 65000).

%%--------------------------------------------------------------------
%% Common Test interface functions -----------------------------------
%%--------------------------------------------------------------------

suite() ->
    [{timetrap,{seconds,60}}].

all() -> 
    case os:find_executable("ssh") of
	false -> 
	    {skip, "openSSH not installed on host"};
	_ ->
	    [{group, erlang_client},
	     {group, erlang_server}
	     ]
    end.

groups() -> 
    [{erlang_client, [], [erlang_shell_client_openssh_server,
			  erlang_client_openssh_server_exec_compressed,
			  erlang_client_openssh_server_setenv,
			  erlang_client_openssh_server_publickey_dsa,
			  erlang_client_openssh_server_publickey_rsa,
			  erlang_client_openssh_server_password,
			  erlang_client_openssh_server_kexs,
			  erlang_client_openssh_server_nonexistent_subsystem,
			  erlang_client_openssh_server_renegotiate
			 ]},
     {erlang_server, [], [erlang_server_openssh_client_public_key_dsa,
			  erlang_server_openssh_client_public_key_rsa,
			  erlang_server_openssh_client_renegotiate
			 ]}
    ].

init_per_suite(Config) ->
    ?CHECK_CRYPTO(
       case gen_tcp:connect("localhost", 22, []) of
	   {error,econnrefused} ->
	       {skip,"No openssh deamon"};
	   _ ->
	       ssh_test_lib:openssh_sanity_check(Config)
       end
      ).

end_per_suite(_Config) ->
    ok.

init_per_group(erlang_server, Config) ->
    DataDir = proplists:get_value(data_dir, Config),
    UserDir = proplists:get_value(priv_dir, Config),
    ssh_test_lib:setup_dsa_known_host(DataDir, UserDir),
    ssh_test_lib:setup_rsa_known_host(DataDir, UserDir),
    Config;
init_per_group(erlang_client, Config) ->
    CommonAlgs = ssh_test_lib:algo_intersection(
		   ssh:default_algorithms(),
		   ssh_test_lib:default_algorithms(sshd)),
    [{common_algs,CommonAlgs} | Config];
init_per_group(_, Config) ->
    Config.

end_per_group(erlang_server, Config) ->
    UserDir = proplists:get_value(priv_dir, Config),
    ssh_test_lib:clean_dsa(UserDir),
    ssh_test_lib:clean_rsa(UserDir),
    Config;
end_per_group(_, Config) ->
    Config.


init_per_testcase(erlang_server_openssh_client_public_key_dsa, Config) ->
    chk_key(sshc, 'ssh-dss', ".ssh/id_dsa", Config);
init_per_testcase(erlang_server_openssh_client_public_key_rsa, Config) ->
    chk_key(sshc, 'ssh-rsa', ".ssh/id_rsa", Config);
init_per_testcase(erlang_client_openssh_server_publickey_dsa, Config) ->
    chk_key(sshd, 'ssh-dss', ".ssh/id_dsa", Config);
init_per_testcase(erlang_server_openssh_client_renegotiate, Config) ->
    case os:type() of
	{unix,_} -> ssh:start(), Config;
	Type -> {skip, io_lib:format("Unsupported test on ~p",[Type])}
    end;
init_per_testcase(_TestCase, Config) ->
    ssh:start(),
    Config.

end_per_testcase(_TestCase, _Config) ->
    ssh:stop(),
    ok.


chk_key(Pgm, Name, File, Config) ->
    case ssh_test_lib:openssh_supports(Pgm, public_key, Name) of
	false ->
	    {skip,lists:concat(["openssh client does not support ",Name])};
	true ->
	    {ok,[[Home]]} = init:get_argument(home),
	    KeyFile =  filename:join(Home, File),
	    case file:read_file(KeyFile) of
		{ok, Pem} ->
		    case public_key:pem_decode(Pem) of
			[{_,_, not_encrypted}] ->
			    init_per_testcase('__default__',Config);
			_ ->
			    {skip, {error, "Has pass phrase can not be used by automated test case"}} 
		    end;
		_ ->
		    {skip, lists:concat(["no ~/",File])}  
	    end
    end.

%%--------------------------------------------------------------------
%% Test Cases --------------------------------------------------------
%%--------------------------------------------------------------------

erlang_shell_client_openssh_server() ->
    [{doc, "Test that ssh:shell/2 works"}].

erlang_shell_client_openssh_server(Config) when is_list(Config) ->
    process_flag(trap_exit, true),
    IO = ssh_test_lib:start_io_server(),
    Shell = ssh_test_lib:start_shell(?SSH_DEFAULT_PORT, IO),
    IO ! {input, self(), "echo Hej\n"},
    receive_data("Hej"),
    IO ! {input, self(), "exit\n"},
    receive_logout(),
    receive_normal_exit(Shell).
   
%--------------------------------------------------------------------
erlang_client_openssh_server_exec() ->
    [{doc, "Test api function ssh_connection:exec"}].

erlang_client_openssh_server_exec(Config) when is_list(Config) ->
    ConnectionRef = ssh_test_lib:connect(?SSH_DEFAULT_PORT, [{silently_accept_hosts, true},
							     {user_interaction, false}]),
    {ok, ChannelId0} = ssh_connection:session_channel(ConnectionRef, infinity),
    success = ssh_connection:exec(ConnectionRef, ChannelId0,
				  "echo testing", infinity),
    Data0 = {ssh_cm, ConnectionRef, {data, ChannelId0, 0, <<"testing\n">>}},
    case ssh_test_lib:receive_exec_result(Data0) of
	expected ->
	    ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId0);
	{unexpected_msg,{ssh_cm, ConnectionRef, {exit_status, ChannelId0, 0}}
	 = ExitStatus0} ->
	    ct:log("0: Collected data ~p", [ExitStatus0]),
	    ssh_test_lib:receive_exec_result(Data0,
					     ConnectionRef, ChannelId0);
	Other0 ->
	    ct:fail(Other0)
    end,

    {ok, ChannelId1} = ssh_connection:session_channel(ConnectionRef, infinity),
    success = ssh_connection:exec(ConnectionRef, ChannelId1,
				  "echo testing1", infinity),
    Data1 = {ssh_cm, ConnectionRef, {data, ChannelId1, 0, <<"testing1\n">>}},
    case ssh_test_lib:receive_exec_result(Data1) of
	expected ->
	    ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId1);
	{unexpected_msg,{ssh_cm, ConnectionRef, {exit_status, ChannelId1, 0}}
	 = ExitStatus1} ->
	    ct:log("0: Collected data ~p", [ExitStatus1]),
	    ssh_test_lib:receive_exec_result(Data1,
					     ConnectionRef, ChannelId1);
	Other1 ->
	    ct:fail(Other1)
    end.

%%--------------------------------------------------------------------
erlang_client_openssh_server_exec_compressed() ->
    [{doc, "Test that compression option works"}].

erlang_client_openssh_server_exec_compressed(Config) when is_list(Config) ->
    CompressAlgs = [zlib, '[email protected]',none],
    case ssh_test_lib:ssh_supports(CompressAlgs, compression) of
	{false,L} ->
	    {skip, io_lib:format("~p compression is not supported",[L])};

	true ->
	    ConnectionRef = ssh_test_lib:connect(?SSH_DEFAULT_PORT, [{silently_accept_hosts, true},
								     {user_interaction, false},
								     {preferred_algorithms,
								      [{compression,CompressAlgs}]}]),
	    {ok, ChannelId} = ssh_connection:session_channel(ConnectionRef, infinity),
	    success = ssh_connection:exec(ConnectionRef, ChannelId,
					  "echo testing", infinity),
	    Data = {ssh_cm, ConnectionRef, {data, ChannelId, 0, <<"testing\n">>}},
	    case ssh_test_lib:receive_exec_result(Data) of
		expected ->
		    ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId);
		{unexpected_msg,{ssh_cm, ConnectionRef,
				 {exit_status, ChannelId, 0}} = ExitStatus} ->
		    ct:log("0: Collected data ~p", [ExitStatus]),
		    ssh_test_lib:receive_exec_result(Data,  ConnectionRef, ChannelId);
		Other ->
		    ct:fail(Other)
	    end
    end.

%%--------------------------------------------------------------------
erlang_client_openssh_server_kexs() ->
    [{doc, "Test that we can connect with different KEXs."}].

erlang_client_openssh_server_kexs(Config) when is_list(Config) ->
    KexAlgos = try proplists:get_value(kex, proplists:get_value(common_algs,Config))
	       catch _:_ -> []
	       end,
    comment(KexAlgos),
    case KexAlgos of
	[] -> {skip, "No common kex algorithms"};
	_ ->
	    Success =
		lists:foldl(
		  fun(Kex, Acc) ->
			  ConnectionRef = 
			      ssh_test_lib:connect(?SSH_DEFAULT_PORT, [{silently_accept_hosts, true},
								       {user_interaction, false},
								       {preferred_algorithms,
									[{kex,[Kex]}]}]),

			  {ok, ChannelId} =
			      ssh_connection:session_channel(ConnectionRef, infinity),
			  success =
			      ssh_connection:exec(ConnectionRef, ChannelId,
						  "echo testing", infinity),

			  ExpectedData = {ssh_cm, ConnectionRef, {data, ChannelId, 0, <<"testing\n">>}},
			  case ssh_test_lib:receive_exec_result(ExpectedData) of
			      expected ->
				  ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId),
				  Acc;
			      {unexpected_msg,{ssh_cm, ConnectionRef,
					       {exit_status, ChannelId, 0}} = ExitStatus} ->
				  ct:log("0: Collected data ~p", [ExitStatus]),
				  ssh_test_lib:receive_exec_result(ExpectedData,  ConnectionRef, ChannelId),
				  Acc;
			      Other ->
				  ct:log("~p failed: ~p",[Kex,Other]),
				  false
			  end
		  end, true, KexAlgos),
	    case Success of
		true ->
		    ok;
		false ->
		    {fail, "Kex failed for one or more algos"}
	    end
    end.

%%--------------------------------------------------------------------
erlang_client_openssh_server_setenv() ->
    [{doc, "Test api function ssh_connection:setenv"}].

erlang_client_openssh_server_setenv(Config) when is_list(Config) ->
    ConnectionRef =
	ssh_test_lib:connect(?SSH_DEFAULT_PORT, [{silently_accept_hosts, true},
						 {user_interaction, false}]),
    {ok, ChannelId} =
	ssh_connection:session_channel(ConnectionRef, infinity),
    Env = case ssh_connection:setenv(ConnectionRef, ChannelId,
				     "ENV_TEST", "testing_setenv",
				     infinity) of
	      success ->
		  <<"tesing_setenv\n">>;
	      failure ->
		  <<"\n">>
	  end,
    success = ssh_connection:exec(ConnectionRef, ChannelId,
				  "echo $ENV_TEST", infinity),
    Data = {ssh_cm, ConnectionRef, {data, ChannelId, 0, Env}},
    case ssh_test_lib:receive_exec_result(Data) of
	expected ->
	    ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId);
	{unexpected_msg,{ssh_cm, ConnectionRef,
			 {data,0,1, UnxpectedData}}} ->
	    %% Some os may return things as
	    %% ENV_TEST: Undefined variable.\n"
	    ct:log("UnxpectedData: ~p", [UnxpectedData]),
	    ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId);
	{unexpected_msg,{ssh_cm, ConnectionRef, {exit_status, ChannelId, 0}}
	 = ExitStatus} ->
	    ct:log("0: Collected data ~p", [ExitStatus]),
	    ssh_test_lib:receive_exec_result(Data,
					     ConnectionRef, ChannelId);
	Other ->
	    ct:fail(Other)
    end.

%%--------------------------------------------------------------------

%% setenv not meaningfull on erlang ssh daemon!

%%--------------------------------------------------------------------
erlang_client_openssh_server_publickey_rsa() ->
    [{doc, "Validate using rsa publickey."}].
erlang_client_openssh_server_publickey_rsa(Config) when is_list(Config) ->
    {ok,[[Home]]} = init:get_argument(home),
    KeyFile =  filename:join(Home, ".ssh/id_rsa"),
    case file:read_file(KeyFile) of
	{ok, Pem} ->
	    case public_key:pem_decode(Pem) of
		[{_,_, not_encrypted}] ->
		    ConnectionRef =
			ssh_test_lib:connect(?SSH_DEFAULT_PORT,
					     [{public_key_alg, ssh_rsa},
					      {user_interaction, false},
					      silently_accept_hosts]),
		    {ok, Channel} =
			ssh_connection:session_channel(ConnectionRef, infinity),
		    ok = ssh_connection:close(ConnectionRef, Channel),
		    ok = ssh:close(ConnectionRef);
		_ ->
		    {skip, {error, "Has pass phrase can not be used by automated test case"}} 
	    end;
	_ ->
	    {skip, "no ~/.ssh/id_rsa"}  
    end.
	

%%--------------------------------------------------------------------
erlang_client_openssh_server_publickey_dsa() ->
    [{doc, "Validate using dsa publickey."}].
erlang_client_openssh_server_publickey_dsa(Config) when is_list(Config) ->
    ConnectionRef =
	ssh_test_lib:connect(?SSH_DEFAULT_PORT,
			     [{public_key_alg, ssh_dsa},
			      {user_interaction, false},
			      silently_accept_hosts]),
    {ok, Channel} =
	ssh_connection:session_channel(ConnectionRef, infinity),
    ok = ssh_connection:close(ConnectionRef, Channel),
    ok = ssh:close(ConnectionRef).

%%--------------------------------------------------------------------
erlang_server_openssh_client_public_key_dsa() ->
    [{timetrap, {seconds,(?TIMEOUT div 1000)+10}},
     {doc, "Validate using dsa publickey."}].
erlang_server_openssh_client_public_key_dsa(Config) when is_list(Config) ->
    erlang_server_openssh_client_public_key_X(Config, ssh_dsa).

erlang_server_openssh_client_public_key_rsa() ->
    [{timetrap, {seconds,(?TIMEOUT div 1000)+10}},
     {doc, "Validate using rsa publickey."}].
erlang_server_openssh_client_public_key_rsa(Config) when is_list(Config) ->
    erlang_server_openssh_client_public_key_X(Config, ssh_rsa).


erlang_server_openssh_client_public_key_X(Config, PubKeyAlg) ->
    SystemDir = proplists:get_value(data_dir, Config),
    PrivDir = proplists:get_value(priv_dir, Config),
    KnownHosts = filename:join(PrivDir, "known_hosts"),
    {Pid, Host, Port} = ssh_test_lib:daemon([{system_dir, SystemDir},
					     {public_key_alg, PubKeyAlg},
					     {failfun, fun ssh_test_lib:failfun/2}]),

    ct:sleep(500),

    Cmd = "ssh -p " ++ integer_to_list(Port) ++
	" -o UserKnownHostsFile=" ++ KnownHosts ++
	" " ++ Host ++ " 1+1.",
    OpenSsh = ssh_test_lib:open_port({spawn, Cmd}),
    ssh_test_lib:rcv_expected({data,<<"2\n">>}, OpenSsh, ?TIMEOUT),
    ssh:stop_daemon(Pid).

%%--------------------------------------------------------------------
%% Test that the Erlang/OTP server can renegotiate with openSSH
erlang_server_openssh_client_renegotiate(Config) ->
    PubKeyAlg = ssh_rsa,
    SystemDir = proplists:get_value(data_dir, Config),
    PrivDir = proplists:get_value(priv_dir, Config),
    KnownHosts = filename:join(PrivDir, "known_hosts"),

    {Pid, Host, Port} = ssh_test_lib:daemon([{system_dir, SystemDir},
					     {public_key_alg, PubKeyAlg},
					     {failfun, fun ssh_test_lib:failfun/2}]),
    ct:sleep(500),

    RenegLimitK = 3,
    DataFile = filename:join(PrivDir, "renegotiate_openssh_client.data"),
    Data =  lists:duplicate(trunc(1.1*RenegLimitK*1024), $a),
    ok = file:write_file(DataFile, Data),

    Cmd = "ssh -p " ++ integer_to_list(Port) ++
	" -o UserKnownHostsFile=" ++ KnownHosts ++
	" -o RekeyLimit=" ++ integer_to_list(RenegLimitK) ++"K" ++
	" " ++ Host ++ " < " ++ DataFile,
    OpenSsh = ssh_test_lib:open_port({spawn, Cmd}),

    Expect = fun({data,R}) -> 
		     try
			 NonAlphaChars = [C || C<-lists:seq(1,255), 
					       not lists:member(C,lists:seq($a,$z)),
					       not lists:member(C,lists:seq($A,$Z))
					 ],
			 Lines = string:tokens(binary_to_list(R), NonAlphaChars),
			 lists:any(fun(L) -> length(L)>1 andalso lists:prefix(L, Data) end,
				   Lines)
		     catch
			 _:_ -> false
		     end;

		({exit_status,E}) when E=/=0 ->
		     ct:log("exit_status ~p",[E]),
		     throw({skip,"exit status"});

		(_) ->
		     false
	     end,
    
    try 
	ssh_test_lib:rcv_expected(Expect, OpenSsh, ?TIMEOUT)
    of
	_ ->
	    %% Unfortunately we can't check that there has been a renegotiation, just trust OpenSSH.
	    ssh:stop_daemon(Pid)
    catch
	throw:{skip,R} -> {skip,R}
    end.

%%--------------------------------------------------------------------
erlang_client_openssh_server_renegotiate(_Config) ->
    process_flag(trap_exit, true),

    IO = ssh_test_lib:start_io_server(),
    Ref = make_ref(),
    Parent = self(),

    Shell = 
	spawn_link(
	  fun() ->
		  Host = ssh_test_lib:hostname(),
		  Options = [{user_interaction, false},
			     {silently_accept_hosts,true}],
		  group_leader(IO, self()),
		  {ok, ConnRef} = ssh:connect(Host, ?SSH_DEFAULT_PORT, Options),
		  case ssh_connection:session_channel(ConnRef, infinity) of
		      {ok,ChannelId}  ->
			  success = ssh_connection:ptty_alloc(ConnRef, ChannelId, []),
			  Args = [{channel_cb, ssh_shell},
				  {init_args,[ConnRef, ChannelId]},
				  {cm, ConnRef}, {channel_id, ChannelId}],
			  {ok, State} = ssh_channel:init([Args]),
			  Parent ! {ok, Ref, ConnRef},
			  ssh_channel:enter_loop(State);
		      Error ->
			  Parent ! {error, Ref, Error}
		  end,
		  receive
		      nothing -> ok
		  end
	  end),

    receive
	{error, Ref, Error} ->
	    ct:fail("Error=~p",[Error]);
	{ok, Ref, ConnectionRef} ->
	    IO ! {input, self(), "echo Hej1\n"},
	    receive_data("Hej1"),
	    Kex1 = ssh_test_lib:get_kex_init(ConnectionRef),
	    ssh_connection_handler:renegotiate(ConnectionRef),
	    IO ! {input, self(), "echo Hej2\n"},
	    receive_data("Hej2"),
	    Kex2 = ssh_test_lib:get_kex_init(ConnectionRef),
	    IO ! {input, self(), "exit\n"},
	    receive_logout(),
	    receive_normal_exit(Shell),
	    true = (Kex1 =/= Kex2)
    end.

%%--------------------------------------------------------------------
erlang_client_openssh_server_password() ->
    [{doc, "Test client password option"}].
erlang_client_openssh_server_password(Config) when is_list(Config) ->
    %% to make sure we don't public-key-auth
    UserDir = proplists:get_value(data_dir, Config),
    {error, Reason0} =
	ssh:connect(any, ?SSH_DEFAULT_PORT, [{silently_accept_hosts, true},
					     {user, "foo"},
					     {password, "morot"},
					     {user_interaction, false},
					     {user_dir, UserDir}]),
    
    ct:log("Test of user foo that does not exist. "
		       "Error msg: ~p~n", [Reason0]),

    User = string:strip(os:cmd("whoami"), right, $\n),

    case length(string:tokens(User, " ")) of
	1 ->
	    {error, Reason1} =
		ssh:connect(any, ?SSH_DEFAULT_PORT,
			    [{silently_accept_hosts, true},
			     {user, User},
			     {password, "foo"},
			     {user_interaction, false},
			     {user_dir, UserDir}]),
	    ct:log("Test of wrong Pasword.  "
			       "Error msg: ~p~n", [Reason1]);
	_ ->
	    ct:log("Whoami failed reason: ~n", [])
	end.

%%--------------------------------------------------------------------

erlang_client_openssh_server_nonexistent_subsystem() ->
    [{doc, "Test client password option"}].
erlang_client_openssh_server_nonexistent_subsystem(Config) when is_list(Config) ->

    ConnectionRef = ssh_test_lib:connect(?SSH_DEFAULT_PORT,
					 [{user_interaction, false},
					  silently_accept_hosts]),

    {ok, ChannelId} = ssh_connection:session_channel(ConnectionRef, infinity),

    failure = ssh_connection:subsystem(ConnectionRef, ChannelId, "foo", infinity).

%%--------------------------------------------------------------------
%
%% Not possible to send password with openssh without user interaction
%%
%%--------------------------------------------------------------------
%%--------------------------------------------------------------------
%%% Internal functions -----------------------------------------------
%%--------------------------------------------------------------------
receive_data(Data) ->
    receive
	Info when is_binary(Info) ->
	    Lines = string:tokens(binary_to_list(Info), "\r\n "),
	    case lists:member(Data, Lines) of
		true ->
		    ct:log("Expected result found in lines: ~p~n", [Lines]),
		    ok;
		false ->
		    ct:log("Extra info: ~p~n", [Info]),
		    receive_data(Data)
	    end;
	Other ->
	    ct:log("Unexpected: ~p",[Other]),
	    receive_data(Data)
    after 
	30000 -> ct:fail("timeout ~p:~p",[?MODULE,?LINE])
    end.	

receive_logout() ->
    receive
	<<"logout">> ->
	    extra_logout(),
	    receive
		<<"Connection closed">> ->
		    ok
	    after 
		30000 -> ct:fail("timeout ~p:~p",[?MODULE,?LINE])
	    end;
	Info ->
	    ct:log("Extra info when logging out: ~p~n", [Info]),
	    receive_logout()
    after 
	30000 -> ct:fail("timeout ~p:~p",[?MODULE,?LINE])
    end.

receive_normal_exit(Shell) ->
    receive
	{'EXIT', Shell, normal} ->
	    ok;
	<<"\r\n">> ->
	    receive_normal_exit(Shell);
	Other ->
	    ct:fail({unexpected_msg, Other})
    after 
	30000 -> ct:fail("timeout ~p:~p",[?MODULE,?LINE])
    end.

extra_logout() ->
    receive 	
	<<"logout">> ->
	    ok
    after 500 -> 
	    ok
    end.

%%--------------------------------------------------------------------
%% Check if we have a "newer" ssh client that supports these test cases
check_ssh_client_support(Config) ->
    case ssh_test_lib:ssh_client_supports_Q() of
	true ->
	    ssh:start(),
	    Config;
	_ ->
	    {skip, "test case not supported by ssh client"}
    end.

comment(AtomList) ->
    ct:comment(
      string:join(lists:map(fun erlang:atom_to_list/1, AtomList),
		", ")).