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-rw-r--r--lib/ssh/doc/src/notes.xml21
-rw-r--r--lib/ssh/doc/src/ssh.xml17
-rw-r--r--lib/ssh/src/ssh.erl6
-rw-r--r--lib/ssh/src/ssh_transport.erl34
-rw-r--r--lib/ssh/test/ssh_basic_SUITE.erl109
-rw-r--r--lib/ssh/vsn.mk2
6 files changed, 182 insertions, 7 deletions
diff --git a/lib/ssh/doc/src/notes.xml b/lib/ssh/doc/src/notes.xml
index acbf3124ef..41885c684c 100644
--- a/lib/ssh/doc/src/notes.xml
+++ b/lib/ssh/doc/src/notes.xml
@@ -29,6 +29,27 @@
<file>notes.xml</file>
</header>
+<section><title>Ssh 3.2.2</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ New option <c>id_string</c> for <c>ssh:daemon</c> and
+ <c>ssh:connect</c> for limiting banner grabbing attempts.</p>
+ <p>
+ The possible values are: <c>{id_string,string()}</c> and
+ <c>{id_string,random}</c>. The latter will make ssh
+ generate a random nonsence id-string for each new
+ connection.</p>
+ <p>
+ Own Id: OTP-12659</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Ssh 3.2.1</title>
<section><title>Fixed Bugs and Malfunctions</title>
diff --git a/lib/ssh/doc/src/ssh.xml b/lib/ssh/doc/src/ssh.xml
index 35b5eb87cb..d49d3ac2a7 100644
--- a/lib/ssh/doc/src/ssh.xml
+++ b/lib/ssh/doc/src/ssh.xml
@@ -205,6 +205,15 @@
<item>
<p>If <c>true</c>, the client does not print anything on authorization.</p>
</item>
+
+ <tag><c><![CDATA[{id_string, random | string()}]]></c></tag>
+ <item>
+ <p>The string that the client presents to a connected server initially. The default value is "Erlang/VSN" where VSN is the ssh application version number.
+ </p>
+ <p>The value <c>random</c> will cause a random string to be created at each connection attempt. This is to make it a bit more difficult for a malicious peer to find the ssh software brand and version.
+ </p>
+ </item>
+
<tag><c><![CDATA[{fd, file_descriptor()}]]></c></tag>
<item>
<p>Allows an existing file descriptor to be used
@@ -385,6 +394,14 @@
</p>
</item>
+ <tag><c><![CDATA[{id_string, random | string()}]]></c></tag>
+ <item>
+ <p>The string the daemon will present to a connecting peer initially. The default value is "Erlang/VSN" where VSN is the ssh application version number.
+ </p>
+ <p>The value <c>random</c> will cause a random string to be created at each connection attempt. This is to make it a bit more difficult for a malicious peer to find the ssh software brand and version.
+ </p>
+ </item>
+
<tag><c><![CDATA[{key_cb, atom()}]]></c></tag>
<item>
<p>Module implementing the behaviour
diff --git a/lib/ssh/src/ssh.erl b/lib/ssh/src/ssh.erl
index 51ad691ba2..d4b02a024e 100644
--- a/lib/ssh/src/ssh.erl
+++ b/lib/ssh/src/ssh.erl
@@ -347,6 +347,8 @@ handle_option([parallel_login|Rest], SocketOptions, SshOptions) ->
handle_option(Rest, SocketOptions, [handle_ssh_option({parallel_login,true}) | SshOptions]);
handle_option([{minimal_remote_max_packet_size, _} = Opt|Rest], SocketOptions, SshOptions) ->
handle_option(Rest, SocketOptions, [handle_ssh_option(Opt) | SshOptions]);
+handle_option([{id_string, _ID} = Opt|Rest], SocketOptions, SshOptions) ->
+ handle_option(Rest, SocketOptions, [handle_ssh_option(Opt) | SshOptions]);
handle_option([Opt | Rest], SocketOptions, SshOptions) ->
handle_option(Rest, [handle_inet_option(Opt) | SocketOptions], SshOptions).
@@ -439,6 +441,10 @@ handle_ssh_option({idle_time, Value} = Opt) when is_integer(Value), Value > 0 ->
Opt;
handle_ssh_option({rekey_limit, Value} = Opt) when is_integer(Value) ->
Opt;
+handle_ssh_option({id_string, random}) ->
+ {id_string, {random,2,5}}; %% 2 - 5 random characters
+handle_ssh_option({id_string, ID} = Opt) when is_list(ID) ->
+ Opt;
handle_ssh_option(Opt) ->
throw({error, {eoptions, Opt}}).
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl
index 76fa776113..8669be570e 100644
--- a/lib/ssh/src/ssh_transport.erl
+++ b/lib/ssh/src/ssh_transport.erl
@@ -44,12 +44,34 @@
versions(client, Options)->
Vsn = proplists:get_value(vsn, Options, ?DEFAULT_CLIENT_VERSION),
- Version = format_version(Vsn),
- {Vsn, Version};
+ {Vsn, format_version(Vsn, software_version(Options))};
versions(server, Options) ->
Vsn = proplists:get_value(vsn, Options, ?DEFAULT_SERVER_VERSION),
- Version = format_version(Vsn),
- {Vsn, Version}.
+ {Vsn, format_version(Vsn, software_version(Options))}.
+
+software_version(Options) ->
+ case proplists:get_value(id_string, Options) of
+ undefined ->
+ "Erlang"++ssh_vsn();
+ {random,Nlo,Nup} ->
+ random_id(Nlo,Nup);
+ ID ->
+ ID
+ end.
+
+ssh_vsn() ->
+ try {ok,L} = application:get_all_key(ssh),
+ proplists:get_value(vsn,L,"")
+ of
+ "" -> "";
+ VSN when is_list(VSN) -> "/" ++ VSN;
+ _ -> ""
+ catch
+ _:_ -> ""
+ end.
+
+random_id(Nlo, Nup) ->
+ [crypto:rand_uniform($a,$z+1) || _<- lists:duplicate(crypto:rand_uniform(Nlo,Nup+1),x) ].
hello_version_msg(Data) ->
[Data,"\r\n"].
@@ -77,9 +99,9 @@ is_valid_mac(Mac, Data, #ssh{recv_mac = Algorithm,
yes_no(Ssh, Prompt) ->
(Ssh#ssh.io_cb):yes_no(Prompt, Ssh).
-format_version({Major,Minor}) ->
+format_version({Major,Minor}, SoftwareVersion) ->
"SSH-" ++ integer_to_list(Major) ++ "." ++
- integer_to_list(Minor) ++ "-Erlang".
+ integer_to_list(Minor) ++ "-" ++ SoftwareVersion.
handle_hello_version(Version) ->
try
diff --git a/lib/ssh/test/ssh_basic_SUITE.erl b/lib/ssh/test/ssh_basic_SUITE.erl
index 3331038450..bd029ad420 100644
--- a/lib/ssh/test/ssh_basic_SUITE.erl
+++ b/lib/ssh/test/ssh_basic_SUITE.erl
@@ -52,6 +52,12 @@ all() ->
ssh_connect_arg4_timeout,
packet_size_zero,
ssh_daemon_minimal_remote_max_packet_size_option,
+ id_string_no_opt_client,
+ id_string_own_string_client,
+ id_string_random_client,
+ id_string_no_opt_server,
+ id_string_own_string_server,
+ id_string_random_server,
{group, hardening_tests}
].
@@ -816,6 +822,66 @@ ssh_daemon_minimal_remote_max_packet_size_option(Config) ->
ssh:stop_daemon(Server).
%%--------------------------------------------------------------------
+id_string_no_opt_client(Config) ->
+ {Server, Host, Port} = fake_daemon(Config),
+ {error,_} = ssh:connect(Host, Port, []),
+ receive
+ {id,Server,"SSH-2.0-Erlang/"++Vsn} ->
+ true = expected_ssh_vsn(Vsn);
+ {id,Server,Other} ->
+ ct:fail("Unexpected id: ~s.",[Other])
+ end.
+
+%%--------------------------------------------------------------------
+id_string_own_string_client(Config) ->
+ {Server, Host, Port} = fake_daemon(Config),
+ {error,_} = ssh:connect(Host, Port, [{id_string,"Pelle"}]),
+ receive
+ {id,Server,"SSH-2.0-Pelle\r\n"} ->
+ ok;
+ {id,Server,Other} ->
+ ct:fail("Unexpected id: ~s.",[Other])
+ end.
+
+%%--------------------------------------------------------------------
+id_string_random_client(Config) ->
+ {Server, Host, Port} = fake_daemon(Config),
+ {error,_} = ssh:connect(Host, Port, [{id_string,random}]),
+ receive
+ {id,Server,Id="SSH-2.0-Erlang"++_} ->
+ ct:fail("Unexpected id: ~s.",[Id]);
+ {id,Server,Rnd="SSH-2.0-"++_} ->
+ ct:log("Got ~s.",[Rnd]);
+ {id,Server,Id} ->
+ ct:fail("Unexpected id: ~s.",[Id])
+ end.
+
+%%--------------------------------------------------------------------
+id_string_no_opt_server(Config) ->
+ {_Server, Host, Port} = std_daemon(Config, []),
+ {ok,S1}=gen_tcp:connect(Host,Port,[{active,false}]),
+ {ok,"SSH-2.0-Erlang/"++Vsn} = gen_tcp:recv(S1, 0, 2000),
+ true = expected_ssh_vsn(Vsn).
+
+%%--------------------------------------------------------------------
+id_string_own_string_server(Config) ->
+ {_Server, Host, Port} = std_daemon(Config, [{id_string,"Olle"}]),
+ {ok,S1}=gen_tcp:connect(Host,Port,[{active,false}]),
+ {ok,"SSH-2.0-Olle\r\n"} = gen_tcp:recv(S1, 0, 2000).
+
+%%--------------------------------------------------------------------
+id_string_random_server(Config) ->
+ {_Server, Host, Port} = std_daemon(Config, [{id_string,random}]),
+ {ok,S1}=gen_tcp:connect(Host,Port,[{active,false}]),
+ {ok,"SSH-2.0-"++Rnd} = gen_tcp:recv(S1, 0, 2000),
+ case Rnd of
+ "Erlang"++_ -> ct:log("Id=~p",[Rnd]),
+ {fail,got_default_id};
+ "Olle\r\n" -> {fail,got_previous_tests_value};
+ _ -> ct:log("Got ~s.",[Rnd])
+ end.
+
+%%--------------------------------------------------------------------
ssh_connect_negtimeout_parallel(Config) -> ssh_connect_negtimeout(Config,true).
ssh_connect_negtimeout_sequential(Config) -> ssh_connect_negtimeout(Config,false).
@@ -1094,3 +1160,46 @@ do_shell(IO, Shell) ->
%% {'EXIT', Shell, killed} ->
%% ok
%% end.
+
+
+std_daemon(Config, ExtraOpts) ->
+ SystemDir = ?config(data_dir, Config),
+ PrivDir = ?config(priv_dir, Config),
+ UserDir = filename:join(PrivDir, nopubkey), % to make sure we don't use public-key-auth
+ file:make_dir(UserDir),
+ {_Server, _Host, _Port} = ssh_test_lib:daemon([{system_dir, SystemDir},
+ {user_dir, UserDir},
+ {failfun, fun ssh_test_lib:failfun/2} | ExtraOpts]).
+
+expected_ssh_vsn(Str) ->
+ try
+ {ok,L} = application:get_all_key(ssh),
+ proplists:get_value(vsn,L,"")++"\r\n"
+ of
+ Str -> true;
+ "\r\n" -> true;
+ _ -> false
+ catch
+ _:_ -> true %% ssh not started so we dont't know
+ end.
+
+
+fake_daemon(_Config) ->
+ Parent = self(),
+ %% start the server
+ Server = spawn(fun() ->
+ {ok,Sl} = gen_tcp:listen(0,[]),
+ {ok,{Host,Port}} = inet:sockname(Sl),
+ Parent ! {sockname,self(),Host,Port},
+ Rsa = gen_tcp:accept(Sl),
+ ct:log("Server gen_tcp:accept got ~p",[Rsa]),
+ {ok,S} = Rsa,
+ receive
+ {tcp, S, Id} -> Parent ! {id,self(),Id}
+ end
+ end),
+ %% Get listening host and port
+ receive
+ {sockname,Server,ServerHost,ServerPort} -> {Server, ServerHost, ServerPort}
+ end.
+
diff --git a/lib/ssh/vsn.mk b/lib/ssh/vsn.mk
index fec8dacab7..b2b85a717f 100644
--- a/lib/ssh/vsn.mk
+++ b/lib/ssh/vsn.mk
@@ -1,4 +1,4 @@
#-*-makefile-*- ; force emacs to enter makefile-mode
-SSH_VSN = 3.2.1
+SSH_VSN = 3.2.2
APP_VSN = "ssh-$(SSH_VSN)"
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-30 13:52:48 +0000