Merge branch 'maint'

* maint:
  ssh: Clear remote user_dir in ssh_compat_SUITE
  ssh: Check compatibility with new OpenSSH versions
  ssh: Fix documentation for public key in ext_info
  ssh: Fix ssh_options checking for ext_info
  ssh: Fix SSH_MSG_EXT_INFO bug for OTP SSH as server
  ssh: Fix SSH_MSG_EXT_INFO bug for OTP SSH as client

4 files changed, 14 insertions, 12 deletions

diff --git a/lib/ssh/src/ssh.hrl b/lib/ssh/src/ssh.hrl
index 233f3caa5d..f645201c4f 100644
--- a/lib/ssh/src/ssh.hrl
+++ b/lib/ssh/src/ssh.hrl
@@ -182,6 +182,7 @@
       | ssh_msg_debug_fun_common_option()
       | rekey_limit_common_option()
       | id_string_common_option()
+      | pref_public_key_algs_common_option()
       | preferred_algorithms_common_option()
       | modify_algorithms_common_option()
       | auth_methods_common_option()
@@ -209,6 +210,7 @@
         {ssh_msg_debug_fun, fun((ssh:connection_ref(),AlwaysDisplay::boolean(),Msg::binary(),LanguageTag::binary()) -> any()) } .
 
 -type id_string_common_option()           :: {id_string,  string() | random | {random,Nmin::pos_integer(),Nmax::pos_integer()} }.
+-type pref_public_key_algs_common_option() :: {pref_public_key_algs, [pubkey_alg()] } .
 -type preferred_algorithms_common_option():: {preferred_algorithms, algs_list()}.
 -type modify_algorithms_common_option()   :: {modify_algorithms,    modify_algs_list()}.
 -type auth_methods_common_option()        :: {auth_methods,         string() }.
@@ -227,8 +229,7 @@
 
 
 -type client_option()         ::
-        pref_public_key_algs_client_option()
-      | ssh_file:pubkey_passphrase_client_options()
+        ssh_file:pubkey_passphrase_client_options()
       | host_accepting_client_options()
       | authentication_client_options()
       | diffie_hellman_group_exchange_client_option()
@@ -242,8 +243,6 @@
         {keyboard_interact_fun, fun((term(),term(),term()) -> term())}
         | opaque_common_options().
 
--type pref_public_key_algs_client_option() :: {pref_public_key_algs, [pubkey_alg()] } .
-
 -type host_accepting_client_options() ::
         {silently_accept_hosts, accept_hosts()}
       | {user_interaction,     boolean()}
diff --git a/lib/ssh/src/ssh_connection_handler.erl b/lib/ssh/src/ssh_connection_handler.erl
index 4b41c10cbb..30eafc2f2a 100644
--- a/lib/ssh/src/ssh_connection_handler.erl
+++ b/lib/ssh/src/ssh_connection_handler.erl
@@ -983,6 +983,10 @@ handle_event(_, #ssh_msg_userauth_info_request{}, {userauth_keyboard_interactive
 
 %%% ######## {connected, client|server} ####
 
+%% Skip ext_info messages in connected state (for example from OpenSSH >= 7.7)
+handle_event(_, #ssh_msg_ext_info{}, {connected,_Role}, D) ->
+    {keep_state, D};
+
 handle_event(_, {#ssh_msg_kexinit{},_}, {connected,Role}, D0) ->
     {KeyInitMsg, SshPacket, Ssh} = ssh_transport:key_exchange_init_msg(D0#data.ssh_params),
     D = D0#data{ssh_params = Ssh,
diff --git a/lib/ssh/src/ssh_options.erl b/lib/ssh/src/ssh_options.erl
index bc9f2156bc..bc9b0b6eda 100644
--- a/lib/ssh/src/ssh_options.erl
+++ b/lib/ssh/src/ssh_options.erl
@@ -452,12 +452,6 @@ default(client) ->
             class => user_options
            },
 
-      {pref_public_key_algs, def} =>
-          #{default => ssh_transport:default_algorithms(public_key),
-            chk => fun check_pref_public_key_algs/1,
-            class => user_options
-           },
-
       {dh_gex_limits, def} =>
           #{default => {1024, 6144, 8192},      % FIXME: Is this true nowadays?
             chk => fun({Min,I,Max}) ->
@@ -523,6 +517,12 @@ default(common) ->
              class => user_options
             },
 
+      {pref_public_key_algs, def} =>
+          #{default => ssh_transport:default_algorithms(public_key),
+            chk => fun check_pref_public_key_algs/1,
+            class => user_options
+           },
+
        {preferred_algorithms, def} =>
            #{default => ssh:default_algorithms(),
              chk => fun check_preferred_algorithms/1,
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl
index c5b0704925..7424c9bcaf 100644
--- a/lib/ssh/src/ssh_transport.erl
+++ b/lib/ssh/src/ssh_transport.erl
@@ -759,8 +759,7 @@ ext_info_message(#ssh{role=server,
                       send_ext_info=true,
                       opts = Opts} = Ssh0) ->
     AlgsList = lists:map(fun erlang:atom_to_list/1,
-                         proplists:get_value(public_key,
-                                             ?GET_OPT(preferred_algorithms, Opts))),
+                         ?GET_OPT(pref_public_key_algs, Opts)),
     Msg = #ssh_msg_ext_info{nr_extensions = 1,
                             data = [{"server-sig-algs", string:join(AlgsList,",")}]
                            },