X-Git-Url: https://gerrit.fd.io/r/gitweb?p=csit.git;a=blobdiff_plain;f=resources%2Flibraries%2Fpython%2FPacketVerifier.py;h=45fab6a7c6bc6298d54a360feb410e57dc597919;hp=566ea95c254187e7d83809658b6a8d71b8bd84bb;hb=3121b691debad27fcea1c6e2031e4a2544e42fbf;hpb=28bd0048f4ebc05c2706b13baf9ae63cedd58a64

diff --git a/resources/libraries/python/PacketVerifier.py b/resources/libraries/python/PacketVerifier.py
index 566ea95c25..45fab6a7c6 100644
--- a/resources/libraries/python/PacketVerifier.py
+++ b/resources/libraries/python/PacketVerifier.py
@@ -73,7 +73,7 @@ from scapy.all import Ether, ARP, Packet
 from scapy.layers.inet6 import IPv6
 
 __all__ = ['RxQueue', 'TxQueue', 'Interface', 'create_gratuitous_arp_request',
-           'auto_pad']
+           'auto_pad', 'checksum_equal']
 
 # TODO: http://stackoverflow.com/questions/320232/ensuring-subprocesses-are-dead-on-exiting-python-program
 
@@ -232,6 +232,7 @@ class RxQueue(PacketVerifier):
             return None
 
         pkt = self._sock.recv(0x7fff)
+        pkt_pad = auto_pad(pkt)
         print 'Received packet on {0} of len {1}'.format(self._ifname, len(pkt))
         Ether(pkt).show2()
         print
@@ -241,7 +242,7 @@ class RxQueue(PacketVerifier):
                 # Auto pad all packets in ignore list
                 ignore[i] = auto_pad(ig_pkt)
             for ig_pkt in ignore:
-                if ig_pkt == pkt:
+                if ig_pkt == pkt_pad:
                     # Found the packet in ignore list, get another one
                     # TODO: subtract timeout - time_spent in here
                     ignore.remove(ig_pkt)
@@ -290,10 +291,6 @@ class Interface(object):
     def recv_pkt(self, timeout=3):
         return self.rxq.recv(timeout, self.sent_packets)
 
-    def close(self):
-        #self.rxq._proc.terminate()
-        pass
-
 
 def create_gratuitous_arp_request(src_mac, src_ip):
     """Creates scapy representation of gratuitous ARP request"""
@@ -308,3 +305,25 @@ def auto_pad(packet):
         padded += ('\0' * (60 - len(padded)))
     return padded
 
+
+def checksum_equal(chksum1, chksum2):
+    """Compares two checksums in one's complement notation.
+
+    Checksums to be compared are calculated as 16 bit one's complement of the
+    one's complement sum of 16 bit words of some buffer.
+    In one's complement notation 0x0000 (positive zero) and 0xFFFF
+    (negative zero) are equivalent.
+
+    :param chksum1: First checksum.
+    :param chksum2: Second checksum.
+    :type chksum1: uint16
+    :type chksum2: uint16
+
+    :return: True if checksums are equivalent, False otherwise.
+    :rtype: boolean
+    """
+    if chksum1 == 0xFFFF:
+        chksum1 = 0
+    if chksum2 == 0xFFFF:
+        chksum2 = 0
+    return chksum1 == chksum2