From 4c3e66d5969e1abe2c8827b756edd860555038a8 Mon Sep 17 00:00:00 2001 From: Hans Nilsson Date: Wed, 31 Oct 2018 15:34:39 +0100 Subject: ssh: Cleaning and polishing of ssh_auth No intentional api changes. Only to make the code less hard to read. --- lib/ssh/src/ssh.hrl | 2 - lib/ssh/src/ssh_auth.erl | 94 +++++++++++++++++++++------------- lib/ssh/src/ssh_connection_handler.erl | 10 ++-- lib/ssh/src/ssh_transport.erl | 5 +- 4 files changed, 66 insertions(+), 45 deletions(-) diff --git a/lib/ssh/src/ssh.hrl b/lib/ssh/src/ssh.hrl index b0a35e0eab..aa4b3ef098 100644 --- a/lib/ssh/src/ssh.hrl +++ b/lib/ssh/src/ssh.hrl @@ -380,8 +380,6 @@ algorithms, %% #alg{} - io_cb, %% Interaction callback module - send_mac = none, %% send MAC algorithm send_mac_key, %% key used in send MAC algorithm send_mac_size = 0, diff --git a/lib/ssh/src/ssh_auth.erl b/lib/ssh/src/ssh_auth.erl index a2f016a837..1972468b8b 100644 --- a/lib/ssh/src/ssh_auth.erl +++ b/lib/ssh/src/ssh_auth.erl @@ -91,8 +91,10 @@ unique(L) -> %%%---- userauth_request_msg "callbacks" -password_msg([#ssh{opts = Opts, io_cb = IoCb, - user = User, service = Service} = Ssh0]) -> +password_msg([#ssh{opts = Opts, + user = User, + service = Service} = Ssh0]) -> + IoCb = ?GET_INTERNAL_OPT(io_cb, Opts), {Password,Ssh} = case ?GET_OPT(password, Opts) of undefined when IoCb == ssh_no_io -> @@ -385,11 +387,9 @@ 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) -> + #ssh{opts=Opts} = Ssh) -> PromptInfos = decode_keyboard_interactive_prompts(NumPrompts,Data), - case keyboard_interact_get_responses(IoCb, Opts, Name, Instr, PromptInfos) of + case keyboard_interact_get_responses(Opts, Name, Instr, PromptInfos) of not_ok -> not_ok; Responses -> @@ -530,56 +530,78 @@ build_sig_data(SessionId, User, Service, KeyBlob, Alg) -> +key_alg('rsa-sha2-256') -> 'ssh-rsa'; +key_alg('rsa-sha2-512') -> 'ssh-rsa'; +key_alg(Alg) -> Alg. + +%%%================================================================ +%%% +%%% Keyboard-interactive +%%% + decode_keyboard_interactive_prompts(_NumPrompts, Data) -> ssh_message:decode_keyboard_interactive_prompts(Data, []). -keyboard_interact_get_responses(IoCb, Opts, Name, Instr, PromptInfos) -> - NumPrompts = length(PromptInfos), +keyboard_interact_get_responses(Opts, Name, Instr, PromptInfos) -> keyboard_interact_get_responses(?GET_OPT(user_interaction, Opts), ?GET_OPT(keyboard_interact_fun, Opts), - ?GET_OPT(password, Opts), IoCb, Name, - Instr, PromptInfos, Opts, NumPrompts). + ?GET_OPT(password, Opts), + Name, + Instr, + PromptInfos, + Opts). -keyboard_interact_get_responses(_, _, not_ok, _, _, _, _, _, _) -> +%% Don't re-try an already rejected password. This could happen if both keyboard-interactive +%% and password methods are tried: +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 -keyboard_interact_get_responses(_, _, _, _, _, _, _, _, 0) -> + +%% Only one password requestedm and we have got one via the 'password' option for the daemon: +keyboard_interact_get_responses(_, undefined, Pwd, _, _, [_], _) when Pwd =/= undefined -> + [Pwd]; %% Password auth implemented with keyboard-interaction and passwd is known + +%% No password requested (keyboard-interactive): +keyboard_interact_get_responses(_, _, _, _, _, [], _) -> []; -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, _) -> - keyboard_interact(IoCb, Name, Instr, PromptInfos, Opts); -keyboard_interact_get_responses(true, Fun, _Pwd, _IoCb, Name, Instr, PromptInfos, _Opts, NumPrompts) -> - keyboard_interact_fun(Fun, Name, Instr, PromptInfos, NumPrompts). - -keyboard_interact(IoCb, Name, Instr, Prompts, Opts) -> + +%% user_interaction is forbidden (by option user_interaction) and we have to ask +%% the user for one or more. +%% Throw an error: +keyboard_interact_get_responses(false, undefined, undefined, _, _, [Prompt|_], Opts) -> + ssh_no_io:read_line(Prompt, Opts); + +%% One or more passwords are requested, we may prompt the user and no fun is used +%% to get the responses: +keyboard_interact_get_responses(true, undefined, _, Name, Instr, PromptInfos, Opts) -> + prompt_user_for_passwords(Name, Instr, PromptInfos, Opts); + +%% The passwords are provided with a fun. Use that one! +keyboard_interact_get_responses(true, Fun, _Pwd, Name, Instr, PromptInfos, _Opts) -> + keyboard_interact_fun(Fun, Name, Instr, PromptInfos). + + + +prompt_user_for_passwords(Name, Instr, PromptInfos, Opts) -> + IoCb = ?GET_INTERNAL_OPT(io_cb, Opts), write_if_nonempty(IoCb, Name), write_if_nonempty(IoCb, Instr), lists:map(fun({Prompt, true}) -> IoCb:read_line(Prompt, Opts); ({Prompt, false}) -> IoCb:read_password(Prompt, Opts) end, - Prompts). - -write_if_nonempty(_, "") -> ok; -write_if_nonempty(_, <<>>) -> ok; -write_if_nonempty(IoCb, Text) -> IoCb:format("~s~n",[Text]). - + PromptInfos). -keyboard_interact_fun(KbdInteractFun, Name, Instr, PromptInfos, NumPrompts) -> - Prompts = lists:map(fun({Prompt, _Echo}) -> Prompt end, - PromptInfos), +keyboard_interact_fun(KbdInteractFun, Name, Instr, PromptInfos) -> + Prompts = lists:map(fun({Prompt,_Echo}) -> Prompt end, PromptInfos), case KbdInteractFun(Name, Instr, Prompts) of - Rs when length(Rs) == NumPrompts -> + Rs when length(Rs) == length(PromptInfos) -> Rs; _Rs -> nok end. -key_alg('rsa-sha2-256') -> 'ssh-rsa'; -key_alg('rsa-sha2-512') -> 'ssh-rsa'; -key_alg(Alg) -> Alg. +write_if_nonempty(_, "") -> ok; +write_if_nonempty(_, <<>>) -> ok; +write_if_nonempty(IoCb, Text) -> IoCb:format("~s~n",[Text]). diff --git a/lib/ssh/src/ssh_connection_handler.erl b/lib/ssh/src/ssh_connection_handler.erl index b64b799327..e23df6ceca 100644 --- a/lib/ssh/src/ssh_connection_handler.erl +++ b/lib/ssh/src/ssh_connection_handler.erl @@ -471,10 +471,11 @@ init_ssh_record(Role, Socket, PeerAddr, Opts) -> S1 = S0#ssh{c_vsn = Vsn, c_version = Version, - io_cb = case ?GET_OPT(user_interaction, Opts) of - true -> ssh_io; - false -> ssh_no_io - end, + opts = ?PUT_INTERNAL_OPT({io_cb, case ?GET_OPT(user_interaction, Opts) of + true -> ssh_io; + false -> ssh_no_io + end}, + Opts), userauth_quiet_mode = ?GET_OPT(quiet_mode, Opts), peer = {PeerName, PeerAddr}, local = LocalName @@ -487,7 +488,6 @@ init_ssh_record(Role, Socket, PeerAddr, Opts) -> server -> S0#ssh{s_vsn = Vsn, s_version = Version, - io_cb = ?GET_INTERNAL_OPT(io_cb, Opts, ssh_io), userauth_methods = string:tokens(AuthMethods, ","), kb_tries_left = 3, peer = {undefined, PeerAddr}, diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl index 96b03abb94..f49b49b2df 100644 --- a/lib/ssh/src/ssh_transport.erl +++ b/lib/ssh/src/ssh_transport.erl @@ -861,8 +861,9 @@ accepted_host(Ssh, PeerName, Public, Opts) -> end. -yes_no(Ssh, Prompt) -> - (Ssh#ssh.io_cb):yes_no(Prompt, Ssh#ssh.opts). +yes_no(#ssh{opts=Opts}, Prompt) -> + IoCb = ?GET_INTERNAL_OPT(io_cb, Opts, ssh_io), + IoCb:yes_no(Prompt, Opts). fmt_hostkey('ssh-rsa') -> "RSA"; -- cgit v1.2.3