From: Matt Kimball <matt.kimball@gmail.com>
Date: Tue, 11 Jul 2017 01:01:25 +0000 (-0700)
Subject: mtr-packet: report ICMP destination unreachable probes as "no route to host"
X-Git-Tag: v0.93~45^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6cc8183d94ca347c0553b8ccb57c04c94f174169;p=thirdparty%2Fmtr.git

mtr-packet: report ICMP destination unreachable probes as "no route to host"

When an ICMP reply of type destination unreachable is received, report
the probe status as "no-route".

The exception is the port unreacable subtype of destination unreachable,
which may occur normally when using a non-ICMP probe type.
---

diff --git a/packet/deconstruct_unix.c b/packet/deconstruct_unix.c
index ce889ca..c09dd64 100644
--- a/packet/deconstruct_unix.c
+++ b/packet/deconstruct_unix.c
@@ -394,6 +394,15 @@ void handle_received_icmp4_packet(
             handle_inner_ip4_packet(net_state, remote_addr,
                                     ICMP_ECHOREPLY, inner_ip, inner_size,
                                     timestamp, mpls_count, mpls);
+        } else {
+            /*
+                ICMP_DEST_UNREACH subtypes other than port unreachable
+                indicate an exceptional condition, and will be reported
+                as a "no route to host" probe response.
+            */
+            handle_inner_ip4_packet(net_state, remote_addr,
+                                    ICMP_DEST_UNREACH, inner_ip, inner_size,
+                                    timestamp, mpls_count, mpls);
         }
     }
 }
@@ -443,6 +452,10 @@ void handle_received_icmp6_packet(
             handle_inner_ip6_packet(net_state, remote_addr,
                                     ICMP_ECHOREPLY, inner_ip, inner_size,
                                     timestamp, mpls_count, mpls);
+        } else {
+            handle_inner_ip6_packet(net_state, remote_addr,
+                                    ICMP_DEST_UNREACH, inner_ip, inner_size,
+                                    timestamp, mpls_count, mpls);
         }
     }
 }
diff --git a/packet/probe.c b/packet/probe.c
index 34ff368..de85b16 100644
--- a/packet/probe.c
+++ b/packet/probe.c
@@ -248,6 +248,8 @@ void respond_to_probe(
 
     if (icmp_type == ICMP_TIME_EXCEEDED) {
         result = "ttl-expired";
+    } else if (icmp_type == ICMP_DEST_UNREACH) {
+        result = "no-route";
     } else {
         assert(icmp_type == ICMP_ECHOREPLY);
         result = "reply";
diff --git a/packet/probe_cygwin.c b/packet/probe_cygwin.c
index a37c5c6..c62cee1 100644
--- a/packet/probe_cygwin.c
+++ b/packet/probe_cygwin.c
@@ -102,14 +102,6 @@ void report_win_error(
     /*  It could be that we got no reply because of timeout  */
     if (err == IP_REQ_TIMED_OUT || err == IP_SOURCE_QUENCH) {
         printf("%d no-reply\n", command_token);
-    } else if (err == IP_DEST_HOST_UNREACHABLE
-               || err == IP_DEST_PORT_UNREACHABLE
-               || err == IP_DEST_PROT_UNREACHABLE
-               || err == IP_DEST_NET_UNREACHABLE
-               || err == IP_DEST_UNREACHABLE
-               || err == IP_DEST_NO_ROUTE
-               || err == IP_BAD_ROUTE || err == IP_BAD_DESTINATION) {
-        printf("%d no-route\n", command_token);
     } else if (err == ERROR_INVALID_NETNAME) {
         printf("%d address-not-available\n", command_token);
     } else if (err == ERROR_INVALID_PARAMETER) {
@@ -186,7 +178,18 @@ void WINAPI on_icmp_reply(
         icmp_type = ICMP_ECHOREPLY;
     } else if (reply_status == IP_TTL_EXPIRED_TRANSIT
                || reply_status == IP_TTL_EXPIRED_REASSEM) {
+
         icmp_type = ICMP_TIME_EXCEEDED;
+    } else if (reply_status == IP_DEST_HOST_UNREACHABLE
+               || reply_status == IP_DEST_PORT_UNREACHABLE
+               || reply_status == IP_DEST_PROT_UNREACHABLE
+               || reply_status == IP_DEST_NET_UNREACHABLE
+               || reply_status == IP_DEST_UNREACHABLE
+               || reply_status == IP_DEST_NO_ROUTE
+               || reply_status == IP_BAD_ROUTE
+               || reply_status == IP_BAD_DESTINATION) {
+
+        icmp_type = ICMP_DEST_UNREACH;
     }
 
     if (icmp_type != -1) {