Handle loopback/any as local address in diameter_tcp/sctp

The support is implied by documentation, but wasn't handled in code. Be
consistent in retrieving the address from the sock rather than the
configuration, and in accepting both ip and ifaddr for a local address.

2 files changed, 81 insertions, 62 deletions

diff --git a/lib/diameter/src/transport/diameter_sctp.erl b/lib/diameter/src/transport/diameter_sctp.erl
index c150252b78..91010105a3 100644
--- a/lib/diameter/src/transport/diameter_sctp.erl
+++ b/lib/diameter/src/transport/diameter_sctp.erl
@@ -156,12 +156,7 @@ start(T, Svc, Opts)
         = Svc,
     diameter_sctp_sup:start(),  %% start supervisors on demand
     Addrs = Caps#diameter_caps.host_ip_address,
-    s(T, Addrs, Pid, lists:map(fun ip/1, Opts)).
-
-ip({ifaddr, A}) ->
-    {ip, A};
-ip(T) ->
-    T.
+    s(T, Addrs, Pid, Opts).
 
 %% A listener spawns transports either as a consequence of this call
 %% when there is not yet an association to assign it, or at comm_up on
@@ -354,23 +349,35 @@ l([], Ref, T) ->
 %% open/3
 
 open(Addrs, Opts, PortNr) ->
-    {LAs, Os} = addrs(Addrs, Opts),
-    {LAs, case gen_sctp:open(gen_opts(portnr(Os, PortNr))) of
-              {ok, Sock} ->
-                  Sock;
-              {error, Reason} ->
-                  x({open, Reason})
-          end}.
+    case gen_sctp:open(gen_opts(portnr(addrs(Addrs, Opts), PortNr))) of
+        {ok, Sock} ->
+            {addrs(Sock), Sock};
+        {error, Reason} ->
+            x({open, Reason})
+    end.
 
 addrs(Addrs, Opts) ->
-    case proplists:split(Opts, [ip]) of
-        {[[]], _} ->
-            {Addrs, Opts ++ [{ip, A} || A <- Addrs]};
-        {[As], Os} ->
-            LAs = [diameter_lib:ipaddr(A) || {ip, A} <- As],
-            {LAs, Os ++ [{ip, A} || A <- LAs]}
+    case lists:mapfoldl(fun ipaddr/2, false, Opts) of
+        {Os, true} ->
+            Os;
+        {_, false} ->
+            Opts ++ [{ip, A} || A <- Addrs]
     end.
 
+ipaddr({K,A}, _)
+  when K == ifaddr;
+       K == ip ->
+    {{ip, ipaddr(A)}, true};
+ipaddr(T, B) ->
+    {T, B}.
+
+ipaddr(A)
+  when A == loopback;
+       A == any ->
+    A;
+ipaddr(A) ->
+    diameter_lib:ipaddr(A).
+
 portnr(Opts, PortNr) ->
     case proplists:get_value(port, Opts) of
         undefined ->
@@ -379,6 +386,14 @@ portnr(Opts, PortNr) ->
             Opts
     end.
 
+addrs(Sock) ->
+    case inet:socknames(Sock) of
+        {ok, As} ->
+            [A || {A,_} <- As];
+        {error, Reason} ->
+            x({socknames, Reason})
+    end.
+
 %% x/1
 
 x(Reason) ->
diff --git a/lib/diameter/src/transport/diameter_tcp.erl b/lib/diameter/src/transport/diameter_tcp.erl
index aa09a261a3..f1536f0865 100644
--- a/lib/diameter/src/transport/diameter_tcp.erl
+++ b/lib/diameter/src/transport/diameter_tcp.erl
@@ -143,8 +143,7 @@
    -> {ok, pid(), [inet:ip_address()]}
  when Ref :: diameter:transport_ref();
            ({connect, Ref}, #diameter_service{}, [connect_option()])
-   -> {ok, pid(), [inet:ip_address()]}
-    | {ok, pid()}
+   -> {ok, pid()}
  when Ref :: diameter:transport_ref().
 
 start({T, Ref}, Svc, Opts) ->
@@ -259,22 +258,14 @@ i(#monitor{parent = Pid, transport = TPid} = S) ->
 
 i({listen, Ref, {Mod, Opts, Addrs}}) ->
     [_] = diameter_config:subscribe(Ref, transport), %% assert existence
-    {[LA, LP], Rest} = proplists:split(Opts, [ip, port]),
-    LAddrOpt = get_addr(LA, Addrs),
-    LPort = get_port(LP),
-    {ok, LSock} = Mod:listen(LPort, gen_opts(LAddrOpt, Rest)),
-    LAddr = laddr(LAddrOpt, Mod, LSock),
+    {[LP], Rest} = proplists:split(Opts, [port]),
+    {ok, LSock} = Mod:listen(get_port(LP), gen_opts(Addrs, Rest)),
+    {ok, {LAddr, _}} = sockname(Mod, LSock),
     true = diameter_reg:add_new({?MODULE, listener, {Ref, {LAddr, LSock}}}),
     proc_lib:init_ack({ok, self(), {LAddr, LSock}}),
     #listener{socket = LSock,
               module = Mod}.
 
-laddr([], Mod, Sock) ->
-    {ok, {Addr, _Port}} = sockname(Mod, Sock),
-    Addr;
-laddr([{ip, Addr}], _, _) ->
-    Addr.
-
 ssl_opts([]) ->
     false;
 ssl_opts([{ssl_options, true}]) ->
@@ -309,24 +300,16 @@ init(accept = T, Ref, Mod, Pid, Opts, Addrs, SvcPid) ->
     Sock;
 
 init(connect = T, Ref, Mod, Pid, Opts, Addrs, _SvcPid) ->
-    {[LA, RA, RP], Rest} = proplists:split(Opts, [ip, raddr, rport]),
-    LAddrOpt = get_addr(LA, Addrs),
+    {[RA, RP], Rest} = proplists:split(Opts, [raddr, rport]),
     RAddr = get_addr(RA),
     RPort = get_port(RP),
-    proc_lib:init_ack(init_rc(LAddrOpt)),
-    Sock = ok(connect(Mod, RAddr, RPort, gen_opts(LAddrOpt, Rest))),
+    proc_lib:init_ack({ok, self()}),
+    Sock = ok(connect(Mod, RAddr, RPort, gen_opts(Addrs, Rest))),
     publish(Mod, T, Ref, Sock),
-    up(Pid, {RAddr, RPort}, LAddrOpt, Mod, Sock),
+    up(Pid, {RAddr, RPort}, Mod, Sock),
     Sock.
 
-init_rc([{ip, Addr}]) ->
-    {ok, self(), [Addr]};
-init_rc([]) ->
-    {ok, self()}.
-
-up(Pid, Remote, [{ip, _Addr}], _, _) ->
-    diameter_peer:up(Pid, Remote);
-up(Pid, Remote, [], Mod, Sock) ->
+up(Pid, Remote, Mod, Sock) ->
     {Addr, _Port} = ok(sockname(Mod, Sock)),
     diameter_peer:up(Pid, Remote, [Addr]).
 
@@ -383,25 +366,41 @@ l([{{?MODULE, listener, {_, AS}}, LPid}], _, _) ->
 l([], Ref, T) ->
     diameter_tcp_sup:start_child({listen, Ref, T}).
 
-%% get_addr/1
+%% addrs/2
+%%
+%% Take the first address from the service if several are specified
+%% and not address is configured.
+
+addrs(Addrs, Opts) ->
+    case lists:mapfoldr(fun ipaddr/2, [], Opts) of
+        {Os, [_]} ->
+            Os;
+        {_, []} ->
+            Opts ++ [{ip, A} || [A|_] <- [Addrs]];
+        {_, As} ->
+            ?ERROR({invalid_addrs, As, Addrs})
+    end.
 
-get_addr(As) ->
-    diameter_lib:ipaddr(addr(As, [])).
+ipaddr({K,A}, As)
+  when K == ifaddr;
+       K == ip ->
+    {{ip, ipaddr(A)}, [A | As]};
+ipaddr(T, B) ->
+    {T, B}.
 
-%% get_addr/2
+ipaddr(A)
+  when A == loopback;
+       A == any ->
+    A;
+ipaddr(A) ->
+    diameter_lib:ipaddr(A).
 
-get_addr([], []) ->
-    [];
-get_addr(As, Def) ->
-    [{ip, diameter_lib:ipaddr(addr(As, Def))}].
+%% get_addr/1
 
-%% Take the first address from the service if several are unspecified.
-addr([], [Addr | _]) ->
-    Addr;
-addr([{_, Addr}], _) ->
-    Addr;
-addr(As, Addrs) ->
-    ?ERROR({invalid_addrs, As, Addrs}).
+get_addr([{_, Addr}]) ->
+    diameter_lib:ipaddr(Addr);
+get_addr(Addrs) ->
+    ?ERROR({invalid_addrs, Addrs}).
 
 %% get_port/1
 
@@ -414,10 +413,15 @@ get_port(Ps) ->
 
 %% gen_opts/2
 
-gen_opts(LAddrOpt, Opts) ->
+gen_opts(Addrs, Opts) ->
+    gen_opts(addrs(Addrs, Opts)).
+
+%% gen_opts/1
+
+gen_opts(Opts) ->
     {L,_} = proplists:split(Opts, [binary, packet, active]),
     [[],[],[]] == L orelse ?ERROR({reserved_options, Opts}),
-    [binary, {packet, 0}, {active, false}] ++ LAddrOpt ++ Opts.
+    [binary, {packet, 0}, {active, false} | Opts].
 
 %% ---------------------------------------------------------------------------
 %% # ports/1