[dts] [PATCH V1 1/5] dep: add igmp.py to dep

[Nannan Lu <nannan.lu@intel.com>]

Add igmp.py to dep so that dts supports
sending igmp packets.

Signed-off-by: Nannan Lu <nannan.lu@intel.com>
---
 dep/igmp.py | 164 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 164 insertions(+)
 create mode 100644 dep/igmp.py

diff --git a/dep/igmp.py b/dep/igmp.py
new file mode 100644
index 0000000..5cbf9c0
--- /dev/null
+++ b/dep/igmp.py
@@ -0,0 +1,164 @@
+#! /usr/bin/env python
+
+# This file is part of Scapy
+# Scapy is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# any later version.
+#
+# Scapy is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Scapy. If not, see <http://www.gnu.org/licenses/>.
+
+# flake8: noqa: E501
+
+# scapy.contrib.description = Internet Group Management Protocol v1/v2 (IGMP/IGMPv2)
+# scapy.contrib.status = loads
+
+from __future__ import print_function
+from scapy.compat import chb, orb
+from scapy.error import warning
+from scapy.fields import ByteEnumField, ByteField, IPField, XShortField
+from scapy.layers.inet import IP, IPOption_Router_Alert
+from scapy.layers.l2 import Ether, getmacbyip
+from scapy.packet import bind_layers, Packet
+from scapy.utils import atol, checksum
+
+
+def isValidMCAddr(ip):
+    """convert dotted quad string to long and check the first octet"""
+    FirstOct = atol(ip) >> 24 & 0xFF
+    return (FirstOct >= 224) and (FirstOct <= 239)
+
+
+class IGMP(Packet):
+    """IGMP Message Class for v1 and v2.
+
+This class is derived from class Packet. You  need call "igmpize()"
+so the packet is transformed according the RFC when sent.
+a=Ether(src="00:01:02:03:04:05")
+b=IP(src="1.2.3.4")
+c=IGMP(type=0x12, gaddr="224.2.3.4")
+x = a/b/c
+x[IGMP].igmpize()
+sendp(a/b/c, iface="en0")
+
+    Parameters:
+      type    IGMP type field, 0x11, 0x12, 0x16 or 0x17
+      mrcode  Maximum Response time (zero for v1)
+      gaddr   Multicast Group Address 224.x.x.x/4
+
+See RFC2236, Section 2. Introduction for definitions of proper
+IGMPv2 message format   http://www.faqs.org/rfcs/rfc2236.html
+
+  """
+    name = "IGMP"
+
+    igmptypes = {0x11: "Group Membership Query",
+                 0x12: "Version 1 - Membership Report",
+                 0x16: "Version 2 - Membership Report",
+                 0x17: "Leave Group"}
+
+    fields_desc = [ByteEnumField("type", 0x11, igmptypes),
+                   ByteField("mrcode", 20),
+                   XShortField("chksum", None),
+                   IPField("gaddr", "0.0.0.0")]
+
+    def post_build(self, p, pay):
+        """Called implicitly before a packet is sent to compute and place IGMP checksum.
+
+        Parameters:
+          self    The instantiation of an IGMP class
+          p       The IGMP message in hex in network byte order
+          pay     Additional payload for the IGMP message
+        """
+        p += pay
+        if self.chksum is None:
+            ck = checksum(p)
+            p = p[:2] + chb(ck >> 8) + chb(ck & 0xff) + p[4:]
+        return p
+
+    @classmethod
+    def dispatch_hook(cls, _pkt=None, *args, **kargs):
+        if _pkt and len(_pkt) >= 4:
+            from scapy.contrib.igmpv3 import IGMPv3
+            if orb(_pkt[0]) in [0x22, 0x30, 0x31, 0x32]:
+                return IGMPv3
+            if orb(_pkt[0]) == 0x11 and len(_pkt) >= 12:
+                return IGMPv3
+        return IGMP
+
+    def igmpize(self):
+        """Called to explicitly fixup the packet according to the IGMP RFC
+
+        The rules are:
+        General:
+            1.  the Max Response time is meaningful only in Membership Queries and should be zero
+        IP:
+            1. Send General Group Query to 224.0.0.1 (all systems)
+            2. Send Leave Group to 224.0.0.2 (all routers)
+            3a.Otherwise send the packet to the group address
+            3b.Send reports/joins to the group address
+            4. ttl = 1 (RFC 2236, section 2)
+            5. send the packet with the router alert IP option (RFC 2236, section 2)
+        Ether:
+            1. Recalculate destination
+
+        Returns:
+            True    The tuple ether/ip/self passed all check and represents
+                    a proper IGMP packet.
+            False   One of more validation checks failed and no fields
+                    were adjusted.
+
+        The function will examine the IGMP message to assure proper format.
+        Corrections will be attempted if possible. The IP header is then properly
+        adjusted to ensure correct formatting and assignment. The Ethernet header
+        is then adjusted to the proper IGMP packet format.
+        """
+        gaddr = self.gaddr if hasattr(self, "gaddr") and self.gaddr else "0.0.0.0"  # noqa: E501
+        underlayer = self.underlayer
+        if self.type not in [0x11, 0x30]:                               # General Rule 1  # noqa: E501
+            self.mrcode = 0
+        if isinstance(underlayer, IP):
+            if (self.type == 0x11):
+                if (gaddr == "0.0.0.0"):
+                    underlayer.dst = "224.0.0.1"                        # IP rule 1  # noqa: E501
+                elif isValidMCAddr(gaddr):
+                    underlayer.dst = gaddr                              # IP rule 3a  # noqa: E501
+                else:
+                    warning("Invalid IGMP Group Address detected !")
+                    return False
+            elif ((self.type == 0x17) and isValidMCAddr(gaddr)):
+                underlayer.dst = "224.0.0.2"                           # IP rule 2  # noqa: E501
+            elif ((self.type == 0x12) or (self.type == 0x16)) and (isValidMCAddr(gaddr)):  # noqa: E501
+                underlayer.dst = gaddr                                 # IP rule 3b  # noqa: E501
+            else:
+                warning("Invalid IGMP Type detected !")
+                return False
+            if not any(isinstance(x, IPOption_Router_Alert) for x in underlayer.options):  # noqa: E501
+                underlayer.options.append(IPOption_Router_Alert())
+            underlayer.ttl = 1                                         # IP rule 4
+            _root = self.firstlayer()
+            if _root.haslayer(Ether):
+                # Force recalculate Ether dst
+                _root[Ether].dst = getmacbyip(underlayer.dst)          # Ether rule 1  # noqa: E501
+        from scapy.contrib.igmpv3 import IGMPv3
+        if isinstance(self, IGMPv3):
+            self.encode_maxrespcode()
+        return True
+
+    def mysummary(self):
+        """Display a summary of the IGMP object."""
+        if isinstance(self.underlayer, IP):
+            return self.underlayer.sprintf("IGMP: %IP.src% > %IP.dst% %IGMP.type% %IGMP.gaddr%")  # noqa: E501
+        else:
+            return self.sprintf("IGMP %IGMP.type% %IGMP.gaddr%")
+
+
+bind_layers(IP, IGMP, frag=0,
+            proto=2,
+            ttl=1)
-- 
2.17.1