Merge branch 'raimo/diffserv-socket-option/OTP-13582' into maint

* raimo/diffserv-socket-option/OTP-13582:
  Tune 'tclass' semantics
  Implement IPV6_TCLASS

4 files changed, 35 insertions, 6 deletions

diff --git a/lib/kernel/doc/src/inet.xml b/lib/kernel/doc/src/inet.xml
index 3f4e3684f4..d907cef7d3 100644
--- a/lib/kernel/doc/src/inet.xml
+++ b/lib/kernel/doc/src/inet.xml
@@ -1092,6 +1092,15 @@ setcap cap_sys_admin,cap_sys_ptrace,cap_dac_read_search+epi beam.smp</code>
               The option is ignored on platforms where it is not
               implemented. Use with caution.</p>
           </item>
+          <tag><c>{tclass, Integer}</c></tag>
+          <item>
+            <p>
+	      Sets <c>IPV6_TCLASS IP</c> level options on platforms
+	      where this is implemented. The behavior and allowed range
+	      varies between different systems.
+              The option is ignored on platforms where it is not
+              implemented. Use with caution.</p>
+          </item>
         </taglist>
         <p>In addition to these options, <em>raw</em>
           option specifications can be used. The raw options are
diff --git a/lib/kernel/src/inet.erl b/lib/kernel/src/inet.erl
index 75dd800c6b..f5c13ecdd7 100644
--- a/lib/kernel/src/inet.erl
+++ b/lib/kernel/src/inet.erl
@@ -677,7 +677,7 @@ parse_strict_address(Addr) ->
 %% Return a list of available options
 options() ->
     [
-     tos, priority, reuseaddr, keepalive, dontroute, linger,
+     tos, tclass, priority, reuseaddr, keepalive, dontroute, linger,
      broadcast, sndbuf, recbuf, nodelay, ipv6_v6only,
      buffer, header, active, packet, deliver, mode,
      multicast_if, multicast_ttl, multicast_loop,
@@ -698,7 +698,7 @@ stats() ->
 %% Available options for tcp:connect
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 connect_options() ->
-    [tos, priority, reuseaddr, keepalive, linger, sndbuf, recbuf, nodelay,
+    [tos, tclass, priority, reuseaddr, keepalive, linger, sndbuf, recbuf, nodelay,
      header, active, packet, packet_size, buffer, mode, deliver, line_delimiter,
      exit_on_close, high_watermark, low_watermark, high_msgq_watermark,
      low_msgq_watermark, send_timeout, send_timeout_close, delay_send, raw,
@@ -766,7 +766,7 @@ con_add(Name, Val, #connect_opts{} = R, Opts, AllOpts) ->
 %% Available options for tcp:listen
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 listen_options() ->
-    [tos, priority, reuseaddr, keepalive, linger, sndbuf, recbuf, nodelay,
+    [tos, tclass, priority, reuseaddr, keepalive, linger, sndbuf, recbuf, nodelay,
      header, active, packet, buffer, mode, deliver, backlog, ipv6_v6only,
      exit_on_close, high_watermark, low_watermark, high_msgq_watermark,
      low_msgq_watermark, send_timeout, send_timeout_close, delay_send,
@@ -846,7 +846,7 @@ tcp_module_1(Opts, Address) ->
 %% Available options for udp:open
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 udp_options() ->
-    [tos, priority, reuseaddr, sndbuf, recbuf, header, active, buffer, mode, 
+    [tos, tclass, priority, reuseaddr, sndbuf, recbuf, header, active, buffer, mode,
      deliver, ipv6_v6only,
      broadcast, dontroute, multicast_if, multicast_ttl, multicast_loop,
      add_membership, drop_membership, read_packets,raw,
@@ -917,7 +917,7 @@ udp_module(Opts) ->
 %  (*) passing of open FDs ("fdopen") is not supported.
 sctp_options() ->
 [   % The following are generic inet options supported for SCTP sockets:
-    mode, active, buffer, tos, priority, dontroute, reuseaddr, linger, sndbuf,
+    mode, active, buffer, tos, tclass, priority, dontroute, reuseaddr, linger, sndbuf,
     recbuf, ipv6_v6only, high_msgq_watermark, low_msgq_watermark,
 
     % Other options are SCTP-specific (though they may be similar to their
diff --git a/lib/kernel/src/inet_int.hrl b/lib/kernel/src/inet_int.hrl
index c8a8962e78..4e8f59a3b9 100644
--- a/lib/kernel/src/inet_int.hrl
+++ b/lib/kernel/src/inet_int.hrl
@@ -153,6 +153,7 @@
 -define(INET_LOPT_NETNS,          38).
 -define(INET_LOPT_TCP_SHOW_ECONNRESET, 39).
 -define(INET_LOPT_LINE_DELIM,     40).
+-define(INET_OPT_TCLASS,          41).
 % Specific SCTP options: separate range:
 -define(SCTP_OPT_RTOINFO,	 	100).
 -define(SCTP_OPT_ASSOCINFO,	 	101).
diff --git a/lib/kernel/test/gen_tcp_api_SUITE.erl b/lib/kernel/test/gen_tcp_api_SUITE.erl
index 77ec89b4f4..92a74465b7 100644
--- a/lib/kernel/test/gen_tcp_api_SUITE.erl
+++ b/lib/kernel/test/gen_tcp_api_SUITE.erl
@@ -38,7 +38,7 @@
 	 t_local_basic/1, t_local_unbound/1, t_local_fdopen/1,
 	 t_local_fdopen_listen/1, t_local_fdopen_listen_unbound/1,
 	 t_local_fdopen_connect/1, t_local_fdopen_connect_unbound/1,
-	 t_local_abstract/1]).
+	 t_local_abstract/1, t_accept_inet6_tclass/1]).
 
 -export([getsockfd/0,closesockfd/1]).
 
@@ -50,6 +50,7 @@ all() ->
     [{group, t_accept}, {group, t_connect}, {group, t_recv},
      t_shutdown_write, t_shutdown_both, t_shutdown_error,
      t_shutdown_async, t_fdopen, t_fdconnect, t_implicit_inet6,
+     t_accept_inet6_tclass,
      {group, t_local}].
 
 groups() -> 
@@ -521,6 +522,24 @@ local_handshake(S, SAddr, C, CAddr) ->
     SData = ok(gen_tcp:recv(C, length(SData))),
     ok.
 
+t_accept_inet6_tclass(Config) when is_list(Config) ->
+    TClassOpt = {tclass,8#56 bsl 2}, % Expedited forwarding
+    case gen_tcp:listen(0, [inet6,TClassOpt]) of
+	{ok,L} ->
+	    LPort = ok(inet:port(L)),
+	    Loopback = {0,0,0,0,0,0,0,1},
+	    Sa = ok(gen_tcp:connect(Loopback, LPort, [])),
+	    Sb = ok(gen_tcp:accept(L)),
+	    [TClassOpt] = ok(inet:getopts(Sb, [tclass])),
+	    ok = gen_tcp:close(Sb),
+	    ok = gen_tcp:close(Sa),
+	    ok = gen_tcp:close(L),
+	    ok;
+	{error,_} ->
+	    {skip,"IPv6 TCLASS not supported"}
+    end.
+
+
 %%% Utilities
 
 %% Calls M:F/length(A), which should return a timeout error, and complete