From 6d086a110feaa69606c004ad6c2d2128606e7b87 Mon Sep 17 00:00:00 2001
From: Jonathan Claudius <jclaudius@mozilla.com>
Date: Thu, 16 Mar 2017 10:55:50 -0400
Subject: [PATCH] Add PTR lookup on IP-only target

---
 lib/ssh_scan/scan_engine.rb |  2 +-
 lib/string_ext.rb           | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/ssh_scan/scan_engine.rb b/lib/ssh_scan/scan_engine.rb
index 1a4bda2d..ce7bd0c5 100644
--- a/lib/ssh_scan/scan_engine.rb
+++ b/lib/ssh_scan/scan_engine.rb
@@ -47,7 +47,7 @@ def scan_target(socket, opts)
         client = SSHScan::Client.new(target, port, timeout)
         client.connect()
         result = client.get_kex_result()
-        result[:hostname] = ""
+        result[:hostname] = target.resolve_ptr
         return result if result.include?(:error)
       end
 
diff --git a/lib/string_ext.rb b/lib/string_ext.rb
index 4db4022d..6584dbfb 100644
--- a/lib/string_ext.rb
+++ b/lib/string_ext.rb
@@ -55,7 +55,18 @@ def resolve_fqdn_as_ipv4(timeout = 3)
   end
 
   def resolve_fqdn
-    @fqdn ||= TCPSocket.gethostbyname(self)[3]
+    TCPSocket.gethostbyname(self)[3]
+  end
+
+  def resolve_ptr(timeout = 3)
+    begin
+      Timeout::timeout(timeout) {
+        reversed_dns = Resolv.new.getname(self)
+        return reversed_dns
+      }
+    rescue Timeout::Error
+      return ""
+    end
   end
 
   def fqdn?