From ca81f1d1602cf994fca9fcd61e892c76e4e2742c Mon Sep 17 00:00:00 2001
From: Micael Karlberg <bmk@erlang.org>
Date: Thu, 12 Jul 2018 11:22:53 +0200
Subject: [socket-nif] Add support for socket (level ip) option recvttl

Added support for the IP option RECVTTL.

OTP-14831
---
 erts/emulator/nifs/common/socket_nif.c |  59 +++++++++++++++++++++++++++++++++
 erts/preloaded/ebin/socket.beam        | Bin 44804 -> 44828 bytes
 erts/preloaded/src/socket.erl          |   9 +++--
 3 files changed, 65 insertions(+), 3 deletions(-)

(limited to 'erts')

diff --git a/erts/emulator/nifs/common/socket_nif.c b/erts/emulator/nifs/common/socket_nif.c
index 0972834cb2..22ac124802 100644
--- a/erts/emulator/nifs/common/socket_nif.c
+++ b/erts/emulator/nifs/common/socket_nif.c
@@ -372,6 +372,7 @@ typedef union {
 #define SOCKET_OPT_IP_MULTICAST_TTL   16
 #define SOCKET_OPT_IP_NODEFRAG        17
 #define SOCKET_OPT_IP_RECVTOS         25
+#define SOCKET_OPT_IP_RECVTTL         26
 #define SOCKET_OPT_IP_ROUTER_ALERT    28
 #define SOCKET_OPT_IP_TOS             30
 #define SOCKET_OPT_IP_TTL             32
@@ -904,6 +905,11 @@ static ERL_NIF_TERM nsetopt_lvl_ip_recvtos(ErlNifEnv*        env,
                                            SocketDescriptor* descP,
                                            ERL_NIF_TERM      eVal);
 #endif
+#if defined(IP_RECVTTL)
+static ERL_NIF_TERM nsetopt_lvl_ip_recvttl(ErlNifEnv*        env,
+                                           SocketDescriptor* descP,
+                                           ERL_NIF_TERM      eVal);
+#endif
 #if defined(IP_ROUTER_ALERT)
 static ERL_NIF_TERM nsetopt_lvl_ip_router_alert(ErlNifEnv*        env,
                                                 SocketDescriptor* descP,
@@ -1099,6 +1105,10 @@ static ERL_NIF_TERM ngetopt_lvl_ip_nodefrag(ErlNifEnv*        env,
 static ERL_NIF_TERM ngetopt_lvl_ip_recvtos(ErlNifEnv*        env,
                                            SocketDescriptor* descP);
 #endif
+#if defined(IP_RECVTTL)
+static ERL_NIF_TERM ngetopt_lvl_ip_recvttl(ErlNifEnv*        env,
+                                           SocketDescriptor* descP);
+#endif
 #if defined(IP_ROUTER_ALERT)
 static ERL_NIF_TERM ngetopt_lvl_ip_router_alert(ErlNifEnv*        env,
                                                 SocketDescriptor* descP);
@@ -4101,6 +4111,12 @@ ERL_NIF_TERM nsetopt_lvl_ip(ErlNifEnv*        env,
         break;
 #endif
 
+#if defined(IP_RECVTTL)
+    case SOCKET_OPT_IP_RECVTTL:
+        result = nsetopt_lvl_ip_recvttl(env, descP, eVal);
+        break;
+#endif
+
 #if defined(IP_ROUTER_ALERT)
     case SOCKET_OPT_IP_ROUTER_ALERT:
         result = nsetopt_lvl_ip_router_alert(env, descP, eVal);
@@ -4398,6 +4414,25 @@ ERL_NIF_TERM nsetopt_lvl_ip_recvtos(ErlNifEnv*        env,
 #endif
 
 
+/* nsetopt_lvl_ip_recvttl - Level IP RECVTTL option
+ */
+#if defined(IP_RECVTTL)
+static
+ERL_NIF_TERM nsetopt_lvl_ip_recvttl(ErlNifEnv*        env,
+                                    SocketDescriptor* descP,
+                                    ERL_NIF_TERM      eVal)
+{
+#if defined(SOL_IP)
+    int level = SOL_IP;
+#else
+    int level = IPPROTO_IP;
+#endif
+
+    return nsetopt_bool_opt(env, descP, level, IP_RECVTTL, eVal);
+}
+#endif
+
+
 /* nsetopt_lvl_ip_router_alert - Level IP ROUTER_ALERT option
  */
 #if defined(IP_ROUTER_ALERT)
@@ -5656,6 +5691,12 @@ ERL_NIF_TERM ngetopt_lvl_ip(ErlNifEnv*        env,
         break;
 #endif
 
+#if defined(IP_RECVTTL)
+    case SOCKET_OPT_IP_RECVTTL:
+        result = ngetopt_lvl_ip_recvttl(env, descP);
+        break;
+#endif
+
 #if defined(IP_ROUTER_ALERT)
     case SOCKET_OPT_IP_ROUTER_ALERT:
         result = ngetopt_lvl_ip_router_alert(env, descP);
@@ -5862,6 +5903,24 @@ ERL_NIF_TERM ngetopt_lvl_ip_recvtos(ErlNifEnv*        env,
 #endif
 
 
+/* ngetopt_lvl_ip_recvttl - Level IP RECVTTL option
+ */
+#if defined(IP_RECVTTL)
+static
+ERL_NIF_TERM ngetopt_lvl_ip_recvttl(ErlNifEnv*        env,
+                                    SocketDescriptor* descP)
+{
+#if defined(SOL_IP)
+    int level = SOL_IP;
+#else
+    int level = IPPROTO_IP;
+#endif
+
+    return ngetopt_bool_opt(env, descP, level, IP_RECVTTL);
+}
+#endif
+
+
 /* ngetopt_lvl_ip_router_alert - Level IP ROUTER_ALERT option
  */
 #if defined(IP_ROUTER_ALERT)
diff --git a/erts/preloaded/ebin/socket.beam b/erts/preloaded/ebin/socket.beam
index 359a329287..2f81e4cc29 100644
Binary files a/erts/preloaded/ebin/socket.beam and b/erts/preloaded/ebin/socket.beam differ
diff --git a/erts/preloaded/src/socket.erl b/erts/preloaded/src/socket.erl
index 3077a794a5..d54c8d5f33 100644
--- a/erts/preloaded/src/socket.erl
+++ b/erts/preloaded/src/socket.erl
@@ -540,7 +540,7 @@
 %% -define(SOCKET_OPT_IP_RECVOPTS,              23).
 %% -define(SOCKET_OPT_IP_RECVORIGDSTADDR,       24).
 -define(SOCKET_OPT_IP_RECVTOS,               25).
-%% -define(SOCKET_OPT_IP_RECVTTL,               26).
+-define(SOCKET_OPT_IP_RECVTTL,               26).
 %% -define(SOCKET_OPT_IP_RETOPTS,               27).
 -define(SOCKET_OPT_IP_ROUTER_ALERT,          28).
 %% -define(SOCKET_OPT_IP_SNDSRCADDR,            29).
@@ -2010,6 +2010,9 @@ enc_setopt_value(ip, nodefrag, V, _D, _T, _P)
 enc_setopt_value(ip, recvtos, V, _D, _T, _P)
   when is_boolean(V) ->
     V;
+enc_setopt_value(ip, recvttl, V, _D, _T, _P)
+  when is_boolean(V) ->
+    V;
 enc_setopt_value(ip, router_alert, V, _D, _T, _P)
   when is_integer(V) ->
     V;
@@ -2323,8 +2326,8 @@ enc_sockopt_key(ip = L, recvorigdstaddr = Opt, _Dir, _D, _T, _P) ->
     not_supported({L, Opt});
 enc_sockopt_key(ip, recvtos = _Opt, _Dir, _D, _T, _P) ->
     ?SOCKET_OPT_IP_RECVTOS;
-enc_sockopt_key(ip = L, recvttl = Opt, _Dir, _D, T, _P) when (T =/= stream) ->
-    not_supported({L, Opt});
+enc_sockopt_key(ip = _L, recvttl = _Opt, _Dir, _D, T, _P) when (T =/= stream) ->
+    ?SOCKET_OPT_IP_RECVTTL;
 enc_sockopt_key(ip = L, retopts = Opt, _Dir, _D, _T, _P) ->
     not_supported({L, Opt});
 enc_sockopt_key(ip, router_alert = _Opt, _Dir, _D, raw = _T, _P) ->
-- 
cgit v1.2.3