%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2004-2015. 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_test_lib).
%% Note: This directive should only be used in test suites.
-compile(export_all).
-include_lib("public_key/include/public_key.hrl").
-include_lib("common_test/include/ct.hrl").
-include_lib("ssh/src/ssh_transport.hrl").
-define(TIMEOUT, 50000).
connect(Options) ->
connect(hostname(), inet_port(), Options).
connect(Port, Options) when is_integer(Port) ->
connect(hostname(), Port, Options);
connect(any, Options) ->
connect(hostname(), inet_port(), Options);
connect(Host, Options) ->
connect(Host, inet_port(), Options).
connect(any, Port, Options) ->
connect(hostname(), Port, Options);
connect(Host, Port, Options) ->
{ok, ConnectionRef} = ssh:connect(Host, Port, Options),
ConnectionRef.
daemon(Options) ->
daemon(any, inet_port(), Options).
daemon(Port, Options) when is_integer(Port) ->
daemon(any, Port, Options);
daemon(Host, Options) ->
daemon(Host, inet_port(), Options).
daemon(Host, Port, Options) ->
case ssh:daemon(Host, Port, Options) of
{ok, Pid} when Host == any ->
{Pid, hostname(), Port};
{ok, Pid} ->
{Pid, Host, Port};
Error ->
Error
end.
std_daemon(Config, ExtraOpts) ->
PrivDir = ?config(priv_dir, Config),
UserDir = filename:join(PrivDir, nopubkey), % to make sure we don't use public-key-auth
file:make_dir(UserDir),
std_daemon1(Config,
ExtraOpts ++
[{user_dir, UserDir},
{user_passwords, [{"usr1","pwd1"}]}]).
std_daemon1(Config, ExtraOpts) ->
SystemDir = ?config(data_dir, Config),
{_Server, _Host, _Port} = ssh_test_lib:daemon([{system_dir, SystemDir},
{failfun, fun ssh_test_lib:failfun/2}
| ExtraOpts]).
std_connect(Config, Host, Port, ExtraOpts) ->
UserDir = ?config(priv_dir, Config),
_ConnectionRef =
ssh_test_lib:connect(Host, Port, [{silently_accept_hosts, true},
{user_dir, UserDir},
{user, "usr1"},
{password, "pwd1"},
{user_interaction, false}
| ExtraOpts]).
std_simple_sftp(Host, Port, Config) ->
std_simple_sftp(Host, Port, Config, []).
std_simple_sftp(Host, Port, Config, Opts) ->
UserDir = ?config(priv_dir, Config),
DataFile = filename:join(UserDir, "test.data"),
ConnectionRef = ssh_test_lib:std_connect(Config, Host, Port, Opts),
{ok, ChannelRef} = ssh_sftp:start_channel(ConnectionRef),
Data = crypto:rand_bytes(proplists:get_value(std_simple_sftp_size,Config,10)),
ok = ssh_sftp:write_file(ChannelRef, DataFile, Data),
{ok,ReadData} = file:read_file(DataFile),
ok = ssh:close(ConnectionRef),
Data == ReadData.
std_simple_exec(Host, Port, Config) ->
std_simple_exec(Host, Port, Config, []).
std_simple_exec(Host, Port, Config, Opts) ->
ConnectionRef = ssh_test_lib:std_connect(Config, Host, Port, Opts),
{ok, ChannelId} = ssh_connection:session_channel(ConnectionRef, infinity),
success = ssh_connection:exec(ConnectionRef, ChannelId, "23+21-2.", infinity),
Data = {ssh_cm, ConnectionRef, {data, ChannelId, 0, <<"42\n">>}},
case ssh_test_lib:receive_exec_result(Data) of
expected ->
ok;
Other ->
ct:fail(Other)
end,
ssh_test_lib:receive_exec_end(ConnectionRef, ChannelId).
start_shell(Port, IOServer, UserDir) ->
start_shell(Port, IOServer, UserDir, []).
start_shell(Port, IOServer, UserDir, Options) ->
spawn_link(?MODULE, init_shell, [Port, IOServer, [{user_dir, UserDir}|Options]]).
start_shell(Port, IOServer) ->
spawn_link(?MODULE, init_shell, [Port, IOServer, []]).
init_shell(Port, IOServer, UserDir) ->
Host = hostname(),
Options = [{user_interaction, false}, {silently_accept_hosts,
true}] ++ UserDir,
group_leader(IOServer, self()),
loop_shell(Host, Port, Options).
loop_shell(Host, Port, Options) ->
ssh:shell(Host, Port, Options).
start_io_server() ->
spawn_link(?MODULE, init_io_server, [self()]).
init_io_server(TestCase) ->
process_flag(trap_exit, true),
loop_io_server(TestCase, []).
loop_io_server(TestCase, Buff0) ->
receive
{input, TestCase, Line} ->
loop_io_server(TestCase, Buff0 ++ [Line]);
{io_request, From, ReplyAs, Request} ->
%%ct:log("~p",[{io_request, From, ReplyAs, Request}]),
{ok, Reply, Buff} = io_request(Request, TestCase, From,
ReplyAs, Buff0),
%%ct:log("io_request(~p)-->~p",[Request,{ok, Reply, Buff}]),
io_reply(From, ReplyAs, Reply),
loop_io_server(TestCase, Buff);
{'EXIT',_, _} ->
erlang:display('ssh_test_lib:loop_io_server/2 EXIT'),
ok
after
30000 -> ct:fail("timeout ~p:~p",[?MODULE,?LINE])
end.
io_request({put_chars, Chars}, TestCase, _, _, Buff) ->
reply(TestCase, Chars),
{ok, ok, Buff};
io_request({put_chars, unicode, Chars}, TestCase, _, _, Buff) when is_binary(Chars) ->
reply(TestCase, Chars),
{ok, ok, Buff};
io_request({put_chars, unicode, io_lib, format, [Fmt,Args]}, TestCase, _, _, Buff) ->
reply(TestCase, io_lib:format(Fmt,Args)),
{ok, ok, Buff};
io_request({put_chars, Enc, Chars}, TestCase, _, _, Buff) ->
reply(TestCase, unicode:characters_to_binary(Chars,Enc,latin1)),
{ok, ok, Buff};
io_request({get_line, _} = Request, _, From, ReplyAs, [] = Buff) ->
erlang:send_after(1000, self(), {io_request, From, ReplyAs, Request}),
{ok, [], Buff};
io_request({get_line, _Enc, _Prompt} = Request, _, From, ReplyAs, [] = Buff) ->
erlang:send_after(1000, self(), {io_request, From, ReplyAs, Request}),
{ok, [], Buff};
io_request({get_line, _Enc,_}, _, _, _, [Line | Buff]) ->
{ok, Line, Buff}.
io_reply(_, _, []) ->
ok;
io_reply(From, ReplyAs, Reply) ->
%%ct:log("io_reply ~p sending ~p ! ~p",[self(),From, {io_reply, ReplyAs, Reply}]),
From ! {io_reply, ReplyAs, Reply}.
reply(_, []) ->
ok;
reply(TestCase, Result) ->
%%ct:log("reply ~p sending ~p ! ~p",[self(), TestCase, Result]),
TestCase ! Result.
receive_exec_result(Msg) ->
ct:log("Expect data! ~p", [Msg]),
receive
{ssh_cm,_,{data,_,1, Data}} ->
ct:log("StdErr: ~p~n", [Data]),
receive_exec_result(Msg);
Msg ->
ct:log("1: Collected data ~p", [Msg]),
expected;
Other ->
ct:log("Other ~p", [Other]),
{unexpected_msg, Other}
after
30000 -> ct:fail("timeout ~p:~p",[?MODULE,?LINE])
end.
receive_exec_end(ConnectionRef, ChannelId) ->
Eof = {ssh_cm, ConnectionRef, {eof, ChannelId}},
ExitStatus = {ssh_cm, ConnectionRef, {exit_status, ChannelId, 0}},
Closed = {ssh_cm, ConnectionRef,{closed, ChannelId}},
case receive_exec_result(ExitStatus) of
{unexpected_msg, Eof} -> %% Open ssh seems to not allways send these messages
%% in the same order!
ct:log("2: Collected data ~p", [Eof]),
case receive_exec_result(ExitStatus) of
expected ->
expected = receive_exec_result(Closed);
{unexpected_msg, Closed} ->
ct:log("3: Collected data ~p", [Closed])
end;
expected ->
ct:log("4: Collected data ~p", [ExitStatus]),
expected = receive_exec_result(Eof),
expected = receive_exec_result(Closed);
Other ->
ct:fail({unexpected_msg, Other})
end.
receive_exec_result(Data, ConnectionRef, ChannelId) ->
Eof = {ssh_cm, ConnectionRef, {eof, ChannelId}},
Closed = {ssh_cm, ConnectionRef,{closed, ChannelId}},
expected = receive_exec_result(Data),
expected = receive_exec_result(Eof),
expected = receive_exec_result(Closed).
inet_port()->
{ok, Socket} = gen_tcp:listen(0, [{reuseaddr, true}]),
{ok, Port} = inet:port(Socket),
gen_tcp:close(Socket),
Port.
setup_ssh_auth_keys(RSAFile, DSAFile, Dir) ->
Entries = ssh_file_entry(RSAFile) ++ ssh_file_entry(DSAFile),
AuthKeys = public_key:ssh_encode(Entries , auth_keys),
AuthKeysFile = filename:join(Dir, "authorized_keys"),
file:write_file(AuthKeysFile, AuthKeys).
ssh_file_entry(PubFile) ->
case file:read_file(PubFile) of
{ok, Ssh} ->
[{Key, _}] = public_key:ssh_decode(Ssh, public_key),
[{Key, [{comment, "Test"}]}];
_ ->
[]
end.
failfun(_User, {authmethod,none}) ->
ok;
failfun(User, Reason) ->
error_logger:format("~p failed XXX to login: ~p~n", [User, Reason]).
hostname() ->
{ok,Host} = inet:gethostname(),
Host.
known_hosts(BR) ->
KnownHosts = ssh_file:file_name(user, "known_hosts", []),
B = KnownHosts ++ "xxx",
case BR of
backup ->
file:rename(KnownHosts, B);
restore ->
file:delete(KnownHosts),
file:rename(B, KnownHosts)
end.
setup_dsa(DataDir, UserDir) ->
file:copy(filename:join(DataDir, "id_dsa"), filename:join(UserDir, "id_dsa")),
System = filename:join(UserDir, "system"),
file:make_dir(System),
file:copy(filename:join(DataDir, "ssh_host_dsa_key"), filename:join(System, "ssh_host_dsa_key")),
file:copy(filename:join(DataDir, "ssh_host_dsa_key.pub"), filename:join(System, "ssh_host_dsa_key.pub")),
ct:pal("DataDir ~p:~n ~p~n~nSystDir ~p:~n ~p~n~nUserDir ~p:~n ~p",[DataDir, file:list_dir(DataDir), System, file:list_dir(System), UserDir, file:list_dir(UserDir)]),
setup_dsa_known_host(DataDir, UserDir),
setup_dsa_auth_keys(DataDir, UserDir).
setup_rsa(DataDir, UserDir) ->
file:copy(filename:join(DataDir, "id_rsa"), filename:join(UserDir, "id_rsa")),
System = filename:join(UserDir, "system"),
file:make_dir(System),
file:copy(filename:join(DataDir, "ssh_host_rsa_key"), filename:join(System, "ssh_host_rsa_key")),
file:copy(filename:join(DataDir, "ssh_host_rsa_key.pub"), filename:join(System, "ssh_host_rsa_key.pub")),
ct:pal("DataDir ~p:~n ~p~n~nSystDir ~p:~n ~p~n~nUserDir ~p:~n ~p",[DataDir, file:list_dir(DataDir), System, file:list_dir(System), UserDir, file:list_dir(UserDir)]),
setup_rsa_known_host(DataDir, UserDir),
setup_rsa_auth_keys(DataDir, UserDir).
setup_ecdsa(Size, DataDir, UserDir) ->
file:copy(filename:join(DataDir, "id_ecdsa"++Size), filename:join(UserDir, "id_ecdsa")),
System = filename:join(UserDir, "system"),
file:make_dir(System),
file:copy(filename:join(DataDir, "ssh_host_ecdsa_key"++Size), filename:join(System, "ssh_host_ecdsa_key")),
file:copy(filename:join(DataDir, "ssh_host_ecdsa_key"++Size++".pub"), filename:join(System, "ssh_host_ecdsa_key.pub")),
ct:pal("DataDir ~p:~n ~p~n~nSystDir ~p:~n ~p~n~nUserDir ~p:~n ~p",[DataDir, file:list_dir(DataDir), System, file:list_dir(System), UserDir, file:list_dir(UserDir)]),
setup_ecdsa_known_host(Size, System, UserDir),
setup_ecdsa_auth_keys(Size, UserDir, UserDir).
clean_dsa(UserDir) ->
del_dirs(filename:join(UserDir, "system")),
file:delete(filename:join(UserDir,"id_dsa")),
file:delete(filename:join(UserDir,"known_hosts")),
file:delete(filename:join(UserDir,"authorized_keys")).
clean_rsa(UserDir) ->
del_dirs(filename:join(UserDir, "system")),
file:delete(filename:join(UserDir,"id_rsa")),
file:delete(filename:join(UserDir,"known_hosts")),
file:delete(filename:join(UserDir,"authorized_keys")).
setup_dsa_pass_pharse(DataDir, UserDir, Phrase) ->
{ok, KeyBin} = file:read_file(filename:join(DataDir, "id_dsa")),
setup_pass_pharse(KeyBin, filename:join(UserDir, "id_dsa"), Phrase),
System = filename:join(UserDir, "system"),
file:make_dir(System),
file:copy(filename:join(DataDir, "ssh_host_dsa_key"), filename:join(System, "ssh_host_dsa_key")),
file:copy(filename:join(DataDir, "ssh_host_dsa_key.pub"), filename:join(System, "ssh_host_dsa_key.pub")),
setup_dsa_known_host(DataDir, UserDir),
setup_dsa_auth_keys(DataDir, UserDir).
setup_rsa_pass_pharse(DataDir, UserDir, Phrase) ->
{ok, KeyBin} = file:read_file(filename:join(DataDir, "id_rsa")),
setup_pass_pharse(KeyBin, filename:join(UserDir, "id_rsa"), Phrase),
System = filename:join(UserDir, "system"),
file:make_dir(System),
file:copy(filename:join(DataDir, "ssh_host_rsa_key"), filename:join(System, "ssh_host_rsa_key")),
file:copy(filename:join(DataDir, "ssh_host_rsa_key.pub"), filename:join(System, "ssh_host_rsa_key.pub")),
setup_rsa_known_host(DataDir, UserDir),
setup_rsa_auth_keys(DataDir, UserDir).
setup_pass_pharse(KeyBin, OutFile, Phrase) ->
[{KeyType, _,_} = Entry0] = public_key:pem_decode(KeyBin),
Key = public_key:pem_entry_decode(Entry0),
Salt = crypto:rand_bytes(8),
Entry = public_key:pem_entry_encode(KeyType, Key,
{{"DES-CBC", Salt}, Phrase}),
Pem = public_key:pem_encode([Entry]),
file:write_file(OutFile, Pem).
setup_dsa_known_host(SystemDir, UserDir) ->
{ok, SshBin} = file:read_file(filename:join(SystemDir, "ssh_host_dsa_key.pub")),
[{Key, _}] = public_key:ssh_decode(SshBin, public_key),
setup_known_hosts(Key, UserDir).
setup_rsa_known_host(SystemDir, UserDir) ->
{ok, SshBin} = file:read_file(filename:join(SystemDir, "ssh_host_rsa_key.pub")),
[{Key, _}] = public_key:ssh_decode(SshBin, public_key),
setup_known_hosts(Key, UserDir).
setup_ecdsa_known_host(_Size, SystemDir, UserDir) ->
{ok, SshBin} = file:read_file(filename:join(SystemDir, "ssh_host_ecdsa_key.pub")),
[{Key, _}] = public_key:ssh_decode(SshBin, public_key),
setup_known_hosts(Key, UserDir).
setup_known_hosts(Key, UserDir) ->
{ok, Hostname} = inet:gethostname(),
{ok, {A, B, C, D}} = inet:getaddr(Hostname, inet),
IP = lists:concat([A, ".", B, ".", C, ".", D]),
HostNames = [{hostnames,[Hostname, IP]}],
KnownHosts = [{Key, HostNames}],
KnownHostsEnc = public_key:ssh_encode(KnownHosts, known_hosts),
KHFile = filename:join(UserDir, "known_hosts"),
file:write_file(KHFile, KnownHostsEnc).
setup_dsa_auth_keys(Dir, UserDir) ->
{ok, Pem} = file:read_file(filename:join(Dir, "id_dsa")),
DSA = public_key:pem_entry_decode(hd(public_key:pem_decode(Pem))),
PKey = DSA#'DSAPrivateKey'.y,
P = DSA#'DSAPrivateKey'.p,
Q = DSA#'DSAPrivateKey'.q,
G = DSA#'DSAPrivateKey'.g,
Dss = #'Dss-Parms'{p=P, q=Q, g=G},
setup_auth_keys([{{PKey, Dss}, [{comment, "Test"}]}], UserDir).
setup_rsa_auth_keys(Dir, UserDir) ->
{ok, Pem} = file:read_file(filename:join(Dir, "id_rsa")),
RSA = public_key:pem_entry_decode(hd(public_key:pem_decode(Pem))),
#'RSAPrivateKey'{publicExponent = E, modulus = N} = RSA,
PKey = #'RSAPublicKey'{publicExponent = E, modulus = N},
setup_auth_keys([{ PKey, [{comment, "Test"}]}], UserDir).
setup_ecdsa_auth_keys(Size, Dir, UserDir) ->
{ok, Pem} = file:read_file(filename:join(Dir, "id_ecdsa")),
ECDSA = public_key:pem_entry_decode(hd(public_key:pem_decode(Pem))),
#'ECPrivateKey'{publicKey = Q,
parameters = {namedCurve,Id0}} = ECDSA,
PKey = #'ECPoint'{point = Q},
Id = case pubkey_cert_records:namedCurves(Id0) of
secp256r1 when Size=="256" -> <<"nistp256">>;
secp384r1 when Size=="384" -> <<"nistp384">>;
secp521r1 when Size=="521" -> <<"nistp521">>
end,
setup_auth_keys([{ {PKey,Id}, [{comment, "Test"}]}], UserDir).
setup_auth_keys(Keys, Dir) ->
AuthKeys = public_key:ssh_encode(Keys, auth_keys),
AuthKeysFile = filename:join(Dir, "authorized_keys"),
file:write_file(AuthKeysFile, AuthKeys).
del_dirs(Dir) ->
case file:list_dir(Dir) of
{ok, []} ->
file:del_dir(Dir);
{ok, Files} ->
lists:foreach(fun(File) ->
FullPath = filename:join(Dir,File),
case filelib:is_dir(FullPath) of
true ->
del_dirs(FullPath),
file:del_dir(FullPath);
false ->
file:delete(FullPath)
end
end, Files);
_ ->
ok
end.
inet_port(Node) ->
{Port, Socket} = do_inet_port(Node),
rpc:call(Node, gen_tcp, close, [Socket]),
Port.
do_inet_port(Node) ->
{ok, Socket} = rpc:call(Node, gen_tcp, listen, [0, [{reuseaddr, true}]]),
{ok, Port} = rpc:call(Node, inet, port, [Socket]),
{Port, Socket}.
openssh_sanity_check(Config) ->
ssh:start(),
case ssh:connect("localhost", 22, [{password,""}]) of
{ok, Pid} ->
ssh:close(Pid),
ssh:stop(),
Config;
Err ->
Str = lists:append(io_lib:format("~p", [Err])),
ssh:stop(),
{skip, Str}
end.
%%--------------------------------------------------------------------
%% Check if we have a "newer" ssh client that supports these test cases
ssh_client_supports_Q() ->
ErlPort = open_port({spawn, "ssh -Q cipher"}, [exit_status, stderr_to_stdout]),
0 == check_ssh_client_support2(ErlPort).
check_ssh_client_support2(P) ->
receive
{P, {data, _A}} ->
check_ssh_client_support2(P);
{P, {exit_status, E}} ->
E
after 5000 ->
ct:log("Openssh command timed out ~n"),
-1
end.
default_algorithms(Host, Port) ->
KexInitPattern =
#ssh_msg_kexinit{
kex_algorithms = '$kex_algorithms',
server_host_key_algorithms = '$server_host_key_algorithms',
encryption_algorithms_client_to_server = '$encryption_algorithms_client_to_server',
encryption_algorithms_server_to_client = '$encryption_algorithms_server_to_client',
mac_algorithms_client_to_server = '$mac_algorithms_client_to_server',
mac_algorithms_server_to_client = '$mac_algorithms_server_to_client',
compression_algorithms_client_to_server = '$compression_algorithms_client_to_server',
compression_algorithms_server_to_client = '$compression_algorithms_server_to_client',
_ = '_'
},
try ssh_trpt_test_lib:exec(
[{connect,Host,Port, [{silently_accept_hosts, true},
{user_interaction, false}]},
{send,hello},
receive_hello,
{send, ssh_msg_kexinit},
{match, KexInitPattern, receive_msg},
close_socket])
of
{ok,E} ->
[Kex, PubKey, EncC2S, EncS2C, MacC2S, MacS2C, CompC2S, CompS2C] =
ssh_trpt_test_lib:instantiate(['$kex_algorithms',
'$server_host_key_algorithms',
'$encryption_algorithms_client_to_server',
'$encryption_algorithms_server_to_client',
'$mac_algorithms_client_to_server',
'$mac_algorithms_server_to_client',
'$compression_algorithms_client_to_server',
'$compression_algorithms_server_to_client'
], E),
[{kex, to_atoms(Kex)},
{public_key, to_atoms(PubKey)},
{cipher, [{client2server, to_atoms(EncC2S)},
{server2client, to_atoms(EncS2C)}]},
{mac, [{client2server, to_atoms(MacC2S)},
{server2client, to_atoms(MacS2C)}]},
{compression, [{client2server, to_atoms(CompC2S)},
{server2client, to_atoms(CompS2C)}]}];
_ ->
[]
catch
_:_ ->
[]
end.
default_algorithms(sshd) ->
default_algorithms("localhost", 22);
default_algorithms(sshc) ->
case os:find_executable("ssh") of
false ->
[];
_ ->
Cipher = sshc(cipher),
Mac = sshc(mac),
[{kex, sshc(kex)},
{public_key, sshc(key)},
{cipher, [{client2server, Cipher},
{server2client, Cipher}]},
{mac, [{client2server, Mac},
{server2client, Mac}]}
]
end.
sshc(Tag) ->
to_atoms(
string:tokens(os:cmd(lists:concat(["ssh -Q ",Tag])), "\n")
).
ssh_type() ->
case os:find_executable("ssh") of
false -> not_found;
_ ->
case os:cmd("ssh -V") of
"OpenSSH" ++ _ ->
openSSH;
Str ->
ct:log("ssh client ~p is unknown",[Str]),
unknown
end
end.
algo_intersection([], _) -> [];
algo_intersection(_, []) -> [];
algo_intersection(L1=[A1|_], L2=[A2|_]) when is_atom(A1), is_atom(A2) ->
true = lists:all(fun erlang:is_atom/1, L1++L2),
lists:foldr(fun(A,Acc) ->
case lists:member(A,L2) of
true -> [A|Acc];
false -> Acc
end
end, [], L1);
algo_intersection([{K,V1}|T1], L2) ->
case lists:keysearch(K,1,L2) of
{value, {K,V2}} ->
[{K,algo_intersection(V1,V2)} | algo_intersection(T1,L2)];
false ->
algo_intersection(T1,L2)
end;
algo_intersection(_, _) ->
[].
to_atoms(L) -> lists:map(fun erlang:list_to_atom/1, L).
%%%----------------------------------------------------------------
ssh_supports(Alg, SshDefaultAlg_tag) ->
SupAlgs =
case proplists:get_value(SshDefaultAlg_tag,
ssh:default_algorithms()) of
[{_K1,L1}, {_K2,L2}] ->
lists:usort(L1++L2);
L ->
L
end,
if
is_atom(Alg) ->
lists:member(Alg, SupAlgs);
is_list(Alg) ->
case Alg--SupAlgs of
[] ->
true;
UnSup ->
{false,UnSup}
end
end.
