Merge branch 'maint-18' into maint

* maint-18:
  Updated OTP version
  Update release notes
  ssh: vsn.mk updated
  ssh: New test cases for SSH_MSG_KEX_DH_GEX_REQUEST_OLD
  ssh: update existing testcases
  ssh: Improve group selection
  ssh: implemented server side SSH_MSG_KEX_DH_GEX_REQUEST_OLD for putty client

Conflicts:
	lib/ssh/src/ssh_transport.erl
	lib/ssh/test/ssh_protocol_SUITE.erl
	lib/ssh/vsn.mk

5 files changed, 97 insertions, 7 deletions

diff --git a/lib/ssh/doc/src/notes.xml b/lib/ssh/doc/src/notes.xml
index 012d7051eb..010b1b15c7 100644
--- a/lib/ssh/doc/src/notes.xml
+++ b/lib/ssh/doc/src/notes.xml
@@ -30,6 +30,22 @@
     <file>notes.xml</file>
   </header>
 
+<section><title>Ssh 4.1.3</title>
+
+    <section><title>Known Bugs and Problems</title>
+      <list>
+        <item>
+          <p>
+	    SSH_MSG_KEX_DH_GEX_REQUEST_OLD implemented to make PuTTY
+	    work with erl server.</p>
+          <p>
+	    Own Id: OTP-13140</p>
+        </item>
+      </list>
+    </section>
+
+</section>
+
 <section><title>Ssh 4.1.2</title>
 
     <section><title>Fixed Bugs and Malfunctions</title>
diff --git a/lib/ssh/src/ssh_connection_handler.erl b/lib/ssh/src/ssh_connection_handler.erl
index 68062209fc..516a09bf6a 100644
--- a/lib/ssh/src/ssh_connection_handler.erl
+++ b/lib/ssh/src/ssh_connection_handler.erl
@@ -433,6 +433,12 @@ key_exchange(#ssh_msg_kex_dh_gex_request{} = Msg,
     send_msg(GexGroup, State),
     {next_state, key_exchange_dh_gex_init, next_packet(State#state{ssh_params = Ssh})};
 
+key_exchange(#ssh_msg_kex_dh_gex_request_old{} = Msg, 
+	     #state{ssh_params = #ssh{role = server} = Ssh0} = State) ->
+    {ok, GexGroup, Ssh} = ssh_transport:handle_kex_dh_gex_request(Msg, Ssh0),
+    send_msg(GexGroup, State),
+    {next_state, key_exchange_dh_gex_init, next_packet(State#state{ssh_params = Ssh})};
+
 key_exchange(#ssh_msg_kex_dh_gex_group{} = Msg, 
 	     #state{ssh_params = #ssh{role = client} = Ssh0} = State) ->
     {ok, KexGexInit, Ssh} = ssh_transport:handle_kex_dh_gex_group(Msg, Ssh0),
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl
index 041e86bae1..67a0d29bb8 100644
--- a/lib/ssh/src/ssh_transport.erl
+++ b/lib/ssh/src/ssh_transport.erl
@@ -433,6 +433,40 @@ handle_kex_dh_gex_request(#ssh_msg_kex_dh_gex_request{min = Min0,
 		     language = ""})
     end;
 
+handle_kex_dh_gex_request(#ssh_msg_kex_dh_gex_request_old{n = NBits}, 
+			  Ssh0=#ssh{opts=Opts}) ->
+    %% server
+    %%
+    %% This message was in the draft-00 of rfc4419
+    %% (https://tools.ietf.org/html/draft-ietf-secsh-dh-group-exchange-00)
+    %% In later drafts and the rfc is "is used for backward compatibility".
+    %% Unfortunatly the rfc does not specify how to treat the parameter n
+    %% if there is no group of that modulus length :(
+    %% The draft-00 however specifies that n is the "... number of bits
+    %% the subgroup should have at least".
+    %% Further, it says that "Servers and clients SHOULD support groups
+    %% with a modulus length of k bits, where 1024 <= k <= 8192."
+    %%
+    Min0 = NBits,
+    Max0 = 8192,
+    {Min, Max} = adjust_gex_min_max(Min0, Max0, Opts),
+    case public_key:dh_gex_group(Min, NBits, Max,
+				 proplists:get_value(dh_gex_groups,Opts)) of
+	{ok, {_Sz, {G,P}}} ->
+	    {Public, Private} = generate_key(dh, [P,G]),
+	    {SshPacket, Ssh} = 
+		ssh_packet(#ssh_msg_kex_dh_gex_group{p = P, g = G}, Ssh0),
+	    {ok, SshPacket, 
+	     Ssh#ssh{keyex_key = {{Private, Public}, {G, P}},
+		     keyex_info = {-1, -1, NBits} % flag for kex_h hash calc
+		    }};
+	{error,_} ->
+	    throw(#ssh_msg_disconnect{
+		     code = ?SSH_DISCONNECT_PROTOCOL_ERROR,
+		     description = "No possible diffie-hellman-group-exchange group found", 
+		     language = ""})
+    end;
+
 handle_kex_dh_gex_request(_, _) ->
   throw({{error,bad_ssh_msg_kex_dh_gex_request},
 	 #ssh_msg_disconnect{
@@ -1571,8 +1605,11 @@ kex_h(SSH, Curve, Key, Q_c, Q_s, K) ->
     crypto:hash(sha(Curve), L).
 
 kex_h(SSH, Key, Min, NBits, Max, Prime, Gen, E, F, K) ->
+    KeyBin = public_key:ssh_encode(Key, ssh2_pubkey),
     L = if Min==-1; Max==-1 ->
-		KeyBin = public_key:ssh_encode(Key, ssh2_pubkey),
+		%% flag from 'ssh_msg_kex_dh_gex_request_old'
+		%% It was like this before that message was supported,
+		%% why?
 		Ts = [string,string,binary,binary,binary,
 		      uint32,
 		      mpint,mpint,mpint,mpint,mpint],
@@ -1581,7 +1618,6 @@ kex_h(SSH, Key, Min, NBits, Max, Prime, Gen, E, F, K) ->
 				 KeyBin, NBits, Prime, Gen, E,F,K],
 				Ts);
 	   true ->
-		KeyBin = public_key:ssh_encode(Key, ssh2_pubkey),
 		Ts = [string,string,binary,binary,binary,
 		      uint32,uint32,uint32,
 		      mpint,mpint,mpint,mpint,mpint],
diff --git a/lib/ssh/test/ssh_protocol_SUITE.erl b/lib/ssh/test/ssh_protocol_SUITE.erl
index 3a7f47c2dd..4639904061 100644
--- a/lib/ssh/test/ssh_protocol_SUITE.erl
+++ b/lib/ssh/test/ssh_protocol_SUITE.erl
@@ -69,7 +69,9 @@ groups() ->
 		gex_client_init_option_groups,
 		gex_server_gex_limit,
 		gex_client_init_option_groups_moduli_file,
-		gex_client_init_option_groups_file
+		gex_client_init_option_groups_file,
+		gex_client_old_request_exact,
+		gex_client_old_request_noexact
 		]},
      {service_requests, [], [bad_service_name,
 			     bad_long_service_name,
@@ -94,7 +96,9 @@ init_per_testcase(no_common_alg_server_disconnects, Config) ->
 init_per_testcase(TC, Config) when TC == gex_client_init_option_groups ;
 				   TC == gex_client_init_option_groups_moduli_file ;
 				   TC == gex_client_init_option_groups_file ;
-				   TC == gex_server_gex_limit ->
+				   TC == gex_server_gex_limit ;
+				   TC == gex_client_old_request_exact ;
+				   TC == gex_client_old_request_noexact ->
     Opts = case TC of
 	       gex_client_init_option_groups ->
 		   [{dh_gex_groups, [{2345, 3, 41}]}];
@@ -106,8 +110,10 @@ init_per_testcase(TC, Config) when TC == gex_client_init_option_groups ;
 		   DataDir = ?config(data_dir, Config),
 		   F = filename:join(DataDir, "dh_group_test.moduli"),
 		   [{dh_gex_groups, {ssh_moduli_file,F}}];
-	       gex_server_gex_limit ->
-		    [{dh_gex_groups, [{ 500, 3, 18},
+	       _ when TC == gex_server_gex_limit ;
+		      TC == gex_client_old_request_exact ;
+		      TC == gex_client_old_request_noexact ->
+		    [{dh_gex_groups, [{ 500, 3, 17},
 				      {1000, 7, 91},
 				      {3000, 5, 61}]},
 		     {dh_gex_limits,{500,1500}}
@@ -126,7 +132,9 @@ end_per_testcase(no_common_alg_server_disconnects, Config) ->
 end_per_testcase(TC, Config) when TC == gex_client_init_option_groups ;
 				  TC == gex_client_init_option_groups_moduli_file ;
 				  TC == gex_client_init_option_groups_file ;
-				  TC == gex_server_gex_limit ->
+				  TC == gex_server_gex_limit ;
+				  TC == gex_client_old_request_exact ;
+				  TC == gex_client_old_request_noexact ->
     stop_std_daemon(Config);
 end_per_testcase(_TestCase, Config) ->
     check_std_daemon_works(Config, ?LINE).
@@ -381,6 +389,29 @@ do_gex_client_init(Config, {Min,N,Max}, {G,P}) ->
 	  ]
 	 ).
 
+%%%--------------------------------------------------------------------
+gex_client_old_request_exact(Config)  ->  do_gex_client_init_old(Config, 500, {3,17}).
+gex_client_old_request_noexact(Config) -> do_gex_client_init_old(Config, 800, {7,91}).
+    
+do_gex_client_init_old(Config, N, {G,P}) ->
+    {ok,_} =
+	ssh_trpt_test_lib:exec(
+	  [{set_options, [print_ops, print_seqnums, print_messages]},
+	   {connect,
+	    server_host(Config),server_port(Config),
+	    [{silently_accept_hosts, true},
+	     {user_dir, user_dir(Config)},
+	     {user_interaction, false},
+	     {preferred_algorithms,[{kex,['diffie-hellman-group-exchange-sha1']}]}
+	    ]},
+	   receive_hello,
+	   {send, hello},
+	   {send, ssh_msg_kexinit},
+	   {match, #ssh_msg_kexinit{_='_'}, receive_msg},
+	   {send, #ssh_msg_kex_dh_gex_request_old{n = N}},
+	   {match, #ssh_msg_kex_dh_gex_group{p=P, g=G, _='_'},  receive_msg}
+	  ]
+	 ).
 
 %%%--------------------------------------------------------------------
 bad_service_name(Config) -> 
diff --git a/lib/ssh/vsn.mk b/lib/ssh/vsn.mk
index d828bccd29..25b19133b1 100644
--- a/lib/ssh/vsn.mk
+++ b/lib/ssh/vsn.mk
@@ -1,4 +1,5 @@
 #-*-makefile-*-   ; force emacs to enter makefile-mode
 
 SSH_VSN = 4.2
+
 APP_VSN    = "ssh-$(SSH_VSN)"