Cleaner fix part 1

[bluesky.git] / parsetrace / split-trace.py

diff --git a/parsetrace/split-trace.py b/parsetrace/split-trace.py
index caf77ee..6af8c72 100755 (executable)
--- a/parsetrace/split-trace.py
+++ b/parsetrace/split-trace.py
@@ -8,12 +8,20 @@ import impacket.ImpactDecoder, impacket.ImpactPacket
 
 # Domain names for cloud service providers, whose traces we want to pull out.
 DOMAINS = ['.amazon.com', '.amazonaws.com', '.core.windows.net',
-           '204.246.162.', '87.238.86.']
+           '204.246.', '87.238.']
 
 # The collection of flows we've seen.  The value associated with each flow is a
 # sequence number indicating in what order we saw the flows in the trace.
 flows = {}
 
+def ip_lookup(host, cache={}):
+    if host not in cache:
+        try:
+            cache[host] = socket.gethostbyaddr(dst)[0]
+        except:
+            cache[host] = host
+    return cache[host]
+
 # Step 1: Parse the input file and extract a listing of all the flows that we
 # care about.
 def handler(header, data):
@@ -47,10 +55,7 @@ for file in sys.argv[1:]:
         # another filter on IP address in case there happened to be any other
         # HTTP flows during the trace capture.
         if dport != 80: continue
-        try:
-            name = socket.gethostbyaddr(dst)[0]
-        except:
-            name = dst
+        name = ip_lookup(dst)
         matches = False
         for d in DOMAINS:
             if name.endswith(d): matches = True