From 0538c5261d7db6a5022dce87852ebb6b7ec876f4 Mon Sep 17 00:00:00 2001
From: emanuele-f <black.silver@hotmail.it>
Date: Sat, 21 Sep 2019 19:25:56 +0200
Subject: [PATCH] Disable PMTU in other platforms

---
 edge.c       |  8 +-------
 edge_utils.c | 19 +++++++++----------
 2 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/edge.c b/edge.c
index c0dc098..6d786ef 100644
--- a/edge.c
+++ b/edge.c
@@ -140,9 +140,7 @@ static void help() {
 	 "-l <supernode host:port>\n"
 	 "    "
 	 "[-p <local port>] [-M <mtu>] "
-#ifdef __linux__
 	 "[-D] "
-#endif
 	 "[-r] [-E] [-v] [-i <reg_interval>] [-t <mgmt port>] [-A] [-h]\n\n");
 
 #if defined(N2N_CAN_NAME_IFACE)
@@ -166,10 +164,8 @@ static void help() {
   printf("-m <MAC address>         | Fix MAC address for the TAP interface (otherwise it may be random)\n"
          "                         | eg. -m 01:02:03:04:05:06\n");
   printf("-M <mtu>                 | Specify n2n MTU of edge interface (default %d).\n", DEFAULT_MTU);
-#ifdef __linux__
   printf("-D                       | Enable PMTU discovery. PMTU discovery can reduce fragmentation but\n"
          "                         | causes connections stall when not properly supported.\n");
-#endif
   printf("-r                       | Enable packet forwarding through n2n community.\n");
 #ifdef N2N_HAVE_AES
   printf("-A                       | Use AES CBC for encryption (default=use twofish).\n");
@@ -257,13 +253,11 @@ static int setOption(int optkey, char *optargument, n2n_priv_config_t *ec, n2n_e
       break;
     }
 
-#ifdef __linux__
   case 'D' : /* enable PMTU discovery */
     {
       conf->disable_pmtu_discovery = 0;
       break;
     }
-#endif
 
   case 'k': /* encrypt key */
     {
@@ -393,7 +387,7 @@ static int loadFromCLI(int argc, char *argv[], n2n_edge_conf_t *conf, n2n_priv_c
   u_char c;
 
   while((c = getopt_long(argc, argv,
-			 "k:a:bc:Eu:g:m:M:s:d:l:p:fvhrt:i:S"
+			 "k:a:bc:Eu:g:m:M:s:d:l:p:fvhrt:i:SD"
 #ifdef N2N_HAVE_AES
 			 "A"
 #endif
diff --git a/edge_utils.c b/edge_utils.c
index 585b4a5..b99f91e 100644
--- a/edge_utils.c
+++ b/edge_utils.c
@@ -1799,6 +1799,8 @@ void edge_term(n2n_edge_t * eee) {
 /* ************************************** */
 
 static int edge_init_sockets(n2n_edge_t *eee, int udp_local_port, int mgmt_port, uint8_t tos) {
+  int sockopt;
+
   if(udp_local_port > 0)
     traceEvent(TRACE_NORMAL, "Binding to local port %d", udp_local_port);
 
@@ -1808,10 +1810,9 @@ static int edge_init_sockets(n2n_edge_t *eee, int udp_local_port, int mgmt_port,
     return(-1);
   }
 
-#ifdef __linux__
   if(tos) {
     /* https://www.tucny.com/Home/dscp-tos */
-    int sockopt = tos;
+    sockopt = tos;
 
     if(setsockopt(eee->udp_sock, IPPROTO_IP, IP_TOS, &sockopt, sizeof(sockopt)) == 0)
       traceEvent(TRACE_NORMAL, "TOS set to 0x%x", tos);
@@ -1819,15 +1820,13 @@ static int edge_init_sockets(n2n_edge_t *eee, int udp_local_port, int mgmt_port,
       traceEvent(TRACE_ERROR, "Could not set TOS 0x%x[%d]: %s", tos, errno, strerror(errno));
   }
 
-  if(eee->conf.disable_pmtu_discovery) {
-    int sockopt = 0;
+  sockopt = (eee->conf.disable_pmtu_discovery) ? IP_PMTUDISC_DONT : IP_PMTUDISC_DO;
 
-    if(setsockopt(eee->udp_sock, IPPROTO_IP, IP_MTU_DISCOVER, &sockopt, sizeof(sockopt)) < 0)
-      traceEvent(TRACE_WARNING, "Could not disable PMTU discovery[%d]: %s", errno, strerror(errno));
-    else
-      traceEvent(TRACE_DEBUG, "PMTU discovery disabled");
-  }
-#endif
+  if(setsockopt(eee->udp_sock, IPPROTO_IP, IP_MTU_DISCOVER, &sockopt, sizeof(sockopt)) < 0)
+    traceEvent(TRACE_WARNING, "Could not %s PMTU discovery[%d]: %s",
+      (eee->conf.disable_pmtu_discovery) ? "disable" : "enable", errno, strerror(errno));
+  else
+    traceEvent(TRACE_DEBUG, "PMTU discovery %s", (eee->conf.disable_pmtu_discovery) ? "disabled" : "enabled");
 
   eee->udp_mgmt_sock = open_socket(mgmt_port, 0 /* bind LOOPBACK */);
   if(eee->udp_mgmt_sock < 0) {