1 files changed, 65 insertions, 0 deletions
diff --git a/scripts/external_libs/scapy-2.3.1/python2/scapy/contrib/carp.py b/scripts/external_libs/scapy-2.3.1/python2/scapy/contrib/carp.py
new file mode 100644
index 00000000..e785adef
--- /dev/null
+++ b/scripts/external_libs/scapy-2.3.1/python2/scapy/contrib/carp.py
@@ -0,0 +1,65 @@
+
+# scapy.contrib.description = CARP
+# scapy.contrib.status = loads
+
+from scapy.packet import *
+from scapy.layers.inet import IP
+from scapy.fields import BitField, ByteField, XShortField, IntField, XIntField
+from scapy.utils import checksum
+import struct, hmac, hashlib
+
+class CARP(Packet):
+    name = "CARP"
+    fields_desc = [ BitField("version", 4, 4),
+        BitField("type", 4, 4),
+        ByteField("vhid", 1),
+        ByteField("advskew", 0),
+        ByteField("authlen", 0),
+        ByteField("demotion", 0),
+        ByteField("advbase", 0),
+        XShortField("chksum", 0),
+        XIntField("counter1", 0),
+        XIntField("counter2", 0),
+        XIntField("hmac1", 0),
+        XIntField("hmac2", 0),
+        XIntField("hmac3", 0),
+        XIntField("hmac4", 0),
+        XIntField("hmac5", 0)
+    ]
+
+    def post_build(self, pkt, pay):
+        if self.chksum == None:
+            pkt = pkt[:6] + struct.pack("!H", checksum(pkt)) + pkt[8:]
+
+        return pkt
+
+def build_hmac_sha1(pkt, pw = '\0' * 20, ip4l = [], ip6l = []):
+    if not pkt.haslayer(CARP):
+        return None 
+
+    p = pkt[CARP]
+    h = hmac.new(pw, digestmod = hashlib.sha1)
+    # XXX: this is a dirty hack. it needs to pack version and type into a single 8bit field
+    h.update('\x21')
+    # XXX: mac addy if different from special link layer. comes before vhid
+    h.update(struct.pack('!B', p.vhid))
+
+    sl = []
+    for i in ip4l:
+        # sort ips from smallest to largest
+        sl.append(inet_aton(i))
+    sl.sort()
+
+    for i in sl:
+        h.update(i)
+
+    # XXX: do ip6l sorting
+
+    return h.digest()
+
+"""
+XXX: Usually CARP is multicast to 224.0.0.18 but because of virtual setup, it'll 
+be unicast between nodes. Uncomment the following line for normal use
+bind_layers(IP, CARP, proto=112, dst='224.0.0.18')
+"""
+bind_layers(IP, CARP, proto=112)