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-rw-r--r--lib/ssh/src/ssh_auth.erl214
1 files changed, 126 insertions, 88 deletions
diff --git a/lib/ssh/src/ssh_auth.erl b/lib/ssh/src/ssh_auth.erl
index 49eec8072f..1c6f656913 100644
--- a/lib/ssh/src/ssh_auth.erl
+++ b/lib/ssh/src/ssh_auth.erl
@@ -31,12 +31,107 @@
-export([publickey_msg/1, password_msg/1, keyboard_interactive_msg/1,
service_request_msg/1, init_userauth_request_msg/1,
userauth_request_msg/1, handle_userauth_request/3,
- handle_userauth_info_request/3, handle_userauth_info_response/2
+ handle_userauth_info_request/2, handle_userauth_info_response/2
]).
%%--------------------------------------------------------------------
%%% Internal application API
%%--------------------------------------------------------------------
+%%%----------------------------------------------------------------
+userauth_request_msg(#ssh{userauth_methods = ServerMethods,
+ userauth_supported_methods = UserPrefMethods, % Note: this is not documented as supported for clients
+ userauth_preference = ClientMethods0
+ } = Ssh0) ->
+ case sort_select_mthds(ClientMethods0, UserPrefMethods, ServerMethods) of
+ [] ->
+ Msg = #ssh_msg_disconnect{code = ?SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE,
+ description = "Unable to connect using the available authentication methods",
+ language = "en"},
+ {disconnect, Msg, ssh_transport:ssh_packet(Msg, Ssh0)};
+
+ [{Pref,Module,Function,Args} | Prefs] ->
+ Ssh = case Pref of
+ "keyboard-interactive" -> Ssh0;
+ _ -> Ssh0#ssh{userauth_preference = Prefs}
+ end,
+ case Module:Function(Args ++ [Ssh]) of
+ {not_ok, Ssh1} ->
+ userauth_request_msg(Ssh1#ssh{userauth_preference = Prefs});
+ Result ->
+ {Pref,Result}
+ end
+ end.
+
+
+
+sort_select_mthds(Clients, undefined, Servers) ->
+ %% User has not expressed an opinion via option "auth_methods", use the server's prefs
+ sort_select_mthds(Clients, Servers, Servers);
+
+sort_select_mthds(Clients, Users0, Servers0) ->
+ %% The User has an opinion, use the intersection of that and the Servers whishes but
+ %% in the Users order
+ Servers = unique(Servers0),
+ Users = unique(Users0),
+ [C || Key <- Users,
+ lists:member(Key, Servers),
+ C <- Clients,
+ element(1,C) == Key].
+
+unique(L) ->
+ lists:reverse(
+ lists:foldl(fun(E,Acc) ->
+ case lists:member(E,Acc) of
+ true -> Acc;
+ false -> [E|Acc]
+ end
+ end, [], L)).
+
+
+%%%---- userauth_request_msg "callbacks"
+password_msg([#ssh{opts = Opts, io_cb = IoCb,
+ user = User, service = Service} = Ssh0]) ->
+ {Password,Ssh} =
+ case proplists:get_value(password, Opts) of
+ undefined when IoCb == ssh_no_io ->
+ {not_ok, Ssh0};
+ undefined ->
+ {IoCb:read_password("ssh password: ",Ssh0), Ssh0};
+ PW ->
+ %% If "password" option is given it should not be tried again
+ {PW, Ssh0#ssh{opts = lists:keyreplace(password,1,Opts,{password,not_ok})}}
+ end,
+ case Password of
+ not_ok ->
+ {not_ok, Ssh};
+ _ ->
+ ssh_transport:ssh_packet(
+ #ssh_msg_userauth_request{user = User,
+ service = Service,
+ method = "password",
+ data =
+ <<?BOOLEAN(?FALSE),
+ ?STRING(unicode:characters_to_binary(Password))>>},
+ Ssh)
+ end.
+
+%% See RFC 4256 for info on keyboard-interactive
+keyboard_interactive_msg([#ssh{user = User,
+ opts = Opts,
+ service = Service} = Ssh]) ->
+ case proplists:get_value(password, Opts) of
+ not_ok ->
+ {not_ok,Ssh}; % No need to use a failed pwd once more
+ _ ->
+ ssh_transport:ssh_packet(
+ #ssh_msg_userauth_request{user = User,
+ service = Service,
+ method = "keyboard-interactive",
+ data = << ?STRING(<<"">>),
+ ?STRING(<<>>) >> },
+ Ssh)
+ end.
+
publickey_msg([Alg, #ssh{user = User,
session_id = SessionId,
service = Service,
@@ -48,7 +143,7 @@ publickey_msg([Alg, #ssh{user = User,
StrAlgo = atom_to_list(Alg),
case encode_public_key(StrAlgo, ssh_transport:extract_public_key(PrivKey)) of
not_ok ->
- not_ok;
+ {not_ok, Ssh};
PubKeyBlob ->
SigData = build_sig_data(SessionId,
User, Service, PubKeyBlob, StrAlgo),
@@ -65,52 +160,15 @@ publickey_msg([Alg, #ssh{user = User,
Ssh)
end;
_Error ->
- not_ok
+ {not_ok, Ssh}
end.
-password_msg([#ssh{opts = Opts, io_cb = IoCb,
- user = User, service = Service} = Ssh]) ->
- Password = case proplists:get_value(password, Opts) of
- undefined ->
- user_interaction(IoCb, Ssh);
- PW ->
- PW
- end,
- case Password of
- not_ok ->
- not_ok;
- _ ->
- ssh_transport:ssh_packet(
- #ssh_msg_userauth_request{user = User,
- service = Service,
- method = "password",
- data =
- <<?BOOLEAN(?FALSE),
- ?STRING(unicode:characters_to_binary(Password))>>},
- Ssh)
- end.
-
-user_interaction(ssh_no_io, _) ->
- not_ok;
-user_interaction(IoCb, Ssh) ->
- IoCb:read_password("ssh password: ", Ssh).
-
-
-%% See RFC 4256 for info on keyboard-interactive
-keyboard_interactive_msg([#ssh{user = User,
- service = Service} = Ssh]) ->
- ssh_transport:ssh_packet(
- #ssh_msg_userauth_request{user = User,
- service = Service,
- method = "keyboard-interactive",
- data = << ?STRING(<<"">>),
- ?STRING(<<>>) >> },
- Ssh).
-
+%%%----------------------------------------------------------------
service_request_msg(Ssh) ->
ssh_transport:ssh_packet(#ssh_msg_service_request{name = "ssh-userauth"},
Ssh#ssh{service = "ssh-userauth"}).
+%%%----------------------------------------------------------------
init_userauth_request_msg(#ssh{opts = Opts} = Ssh) ->
case user_name(Opts) of
{ok, User} ->
@@ -140,34 +198,9 @@ init_userauth_request_msg(#ssh{opts = Opts} = Ssh) ->
description = ErrStr})
end.
-userauth_request_msg(#ssh{userauth_preference = []} = Ssh) ->
- Msg = #ssh_msg_disconnect{code =
- ?SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE,
- description = "Unable to connect using the available"
- " authentication methods",
- language = "en"},
- {disconnect, Msg, ssh_transport:ssh_packet(Msg, Ssh)};
-
-userauth_request_msg(#ssh{userauth_methods = Methods,
- userauth_preference = [{Pref, Module,
- Function, Args} | Prefs]}
- = Ssh0) ->
- Ssh = Ssh0#ssh{userauth_preference = Prefs},
- case lists:member(Pref, Methods) of
- true ->
- case Module:Function(Args ++ [Ssh]) of
- not_ok ->
- userauth_request_msg(Ssh);
- Result ->
- {Pref,Result}
- end;
- false ->
- userauth_request_msg(Ssh)
- end.
-
-
-handle_userauth_request(#ssh_msg_service_request{name =
- Name = "ssh-userauth"},
+%%%----------------------------------------------------------------
+%%% called by server
+handle_userauth_request(#ssh_msg_service_request{name = Name = "ssh-userauth"},
_, Ssh) ->
{ok, ssh_transport:ssh_packet(#ssh_msg_service_accept{name = Name},
Ssh#ssh{service = "ssh-connection"})};
@@ -319,21 +352,28 @@ handle_userauth_request(#ssh_msg_userauth_request{user = User,
partial_success = false}, Ssh)}.
-
-handle_userauth_info_request(
- #ssh_msg_userauth_info_request{name = Name,
- instruction = Instr,
- num_prompts = NumPrompts,
- data = Data}, IoCb,
- #ssh{opts = Opts} = Ssh) ->
+%%%----------------------------------------------------------------
+%%% keyboard-interactive client
+handle_userauth_info_request(#ssh_msg_userauth_info_request{name = Name,
+ instruction = Instr,
+ num_prompts = NumPrompts,
+ data = Data},
+ #ssh{opts = Opts,
+ io_cb = IoCb
+ } = Ssh) ->
PromptInfos = decode_keyboard_interactive_prompts(NumPrompts,Data),
- Responses = keyboard_interact_get_responses(IoCb, Opts,
- Name, Instr, PromptInfos),
- {ok,
- ssh_transport:ssh_packet(
- #ssh_msg_userauth_info_response{num_responses = NumPrompts,
- data = Responses}, Ssh)}.
+ case keyboard_interact_get_responses(IoCb, Opts, Name, Instr, PromptInfos) of
+ not_ok ->
+ not_ok;
+ Responses ->
+ {ok,
+ ssh_transport:ssh_packet(
+ #ssh_msg_userauth_info_response{num_responses = NumPrompts,
+ data = Responses}, Ssh)}
+ end.
+%%%----------------------------------------------------------------
+%%% keyboard-interactive server
handle_userauth_info_response(#ssh_msg_userauth_info_response{num_responses = 1,
data = <<?UINT32(Sz), Password:Sz/binary>>},
#ssh{opts = Opts,
@@ -369,11 +409,6 @@ method_preference(Algs) ->
[{"publickey", ?MODULE, publickey_msg, [A]} | Acc]
end,
[{"password", ?MODULE, password_msg, []},
- {"keyboard-interactive", ?MODULE, keyboard_interactive_msg, []},
- {"keyboard-interactive", ?MODULE, keyboard_interactive_msg, []},
- {"keyboard-interactive", ?MODULE, keyboard_interactive_msg, []},
- {"keyboard-interactive", ?MODULE, keyboard_interactive_msg, []},
- {"keyboard-interactive", ?MODULE, keyboard_interactive_msg, []},
{"keyboard-interactive", ?MODULE, keyboard_interactive_msg, []}
],
Algs).
@@ -473,6 +508,9 @@ keyboard_interact_get_responses(IoCb, Opts, Name, Instr, PromptInfos) ->
proplists:get_value(password, Opts, undefined), IoCb, Name,
Instr, PromptInfos, Opts, NumPrompts).
+
+keyboard_interact_get_responses(_, _, not_ok, _, _, _, _, _, _) ->
+ not_ok;
keyboard_interact_get_responses(_, undefined, Password, _, _, _, _, _,
1) when Password =/= undefined ->
[Password]; %% Password auth implemented with keyboard-interaction and passwd is known
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 21:07:30 +0000