ssh: Improve 'server-sig-algs' handling in client

1 files changed, 34 insertions, 25 deletions

diff --git a/lib/ssh/src/ssh_auth.erl b/lib/ssh/src/ssh_auth.erl
index 6cf659f830..ac64a7bf14 100644
--- a/lib/ssh/src/ssh_auth.erl
+++ b/lib/ssh/src/ssh_auth.erl
@@ -28,7 +28,8 @@
 -include("ssh_auth.hrl").
 -include("ssh_transport.hrl").
 
--export([publickey_msg/1, password_msg/1, keyboard_interactive_msg/1,
+-export([get_public_key/2,
+         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/2, handle_userauth_info_response/2
@@ -136,41 +137,49 @@ keyboard_interactive_msg([#ssh{user = User,
 	      Ssh)
     end.
 
-publickey_msg([SigAlg, #ssh{user = User,
-		       session_id = SessionId,
-		       service = Service,
-		       opts = Opts} = Ssh]) ->
-    Hash = ssh_transport:sha(SigAlg),
+
+get_public_key(SigAlg, #ssh{opts = Opts}) ->
     KeyAlg = key_alg(SigAlg),
     {KeyCb,KeyCbOpts} = ?GET_OPT(key_cb, Opts),
     UserOpts = ?GET_OPT(user_options, Opts),
     case KeyCb:user_key(KeyAlg, [{key_cb_private,KeyCbOpts}|UserOpts]) of
-	{ok, PrivKey} ->
-	    SigAlgStr = atom_to_list(SigAlg),
+        {ok, PrivKey} ->
             try
                 Key = ssh_transport:extract_public_key(PrivKey),
                 public_key:ssh_encode(Key, ssh2_pubkey)
             of
-		PubKeyBlob ->
-		    SigData = build_sig_data(SessionId, User, Service,
-                                             PubKeyBlob, SigAlgStr),
-		    Sig = ssh_transport:sign(SigData, Hash, PrivKey),
-		    SigBlob = list_to_binary([?string(SigAlgStr),
-                                              ?binary(Sig)]),
-		    ssh_transport:ssh_packet(
-		      #ssh_msg_userauth_request{user = User,
-						service = Service,
-						method = "publickey",
-						data = [?TRUE,
-							?string(SigAlgStr),
-							?binary(PubKeyBlob),
-							?binary(SigBlob)]},
-		      Ssh)
+                PubKeyBlob -> {ok,{PrivKey,PubKeyBlob}}
             catch
                 _:_ -> 
-		    {not_ok, Ssh}
+		    not_ok
             end;
-     	_Error ->
+	_Error ->
+	    not_ok
+    end.
+
+
+publickey_msg([SigAlg, #ssh{user = User,
+		       session_id = SessionId,
+		       service = Service} = Ssh]) ->
+    case get_public_key(SigAlg, Ssh) of
+	{ok, {PrivKey,PubKeyBlob}} ->
+            SigAlgStr = atom_to_list(SigAlg),
+            SigData = build_sig_data(SessionId, User, Service,
+                                     PubKeyBlob, SigAlgStr),
+            Hash = ssh_transport:sha(SigAlg),
+            Sig = ssh_transport:sign(SigData, Hash, PrivKey),
+            SigBlob = list_to_binary([?string(SigAlgStr),
+                                      ?binary(Sig)]),
+            ssh_transport:ssh_packet(
+              #ssh_msg_userauth_request{user = User,
+                                        service = Service,
+                                        method = "publickey",
+                                        data = [?TRUE,
+                                                ?string(SigAlgStr),
+                                                ?binary(PubKeyBlob),
+                                                ?binary(SigBlob)]},
+              Ssh);
+     	_ ->
 	    {not_ok, Ssh}
     end.