T959: XML/Python rewrite of "protocol igmp-proxy" and op-mode commands

Examples:
=========

CFG commands:

  vyos@vyos# set protocols igmp-proxy disable-quickleave
  vyos@vyos# set protocols igmp-proxy interface eth0 alt-subnet '172.16.35.0/24'
  vyos@vyos# set protocols igmp-proxy interface eth0 alt-subnet '172.31.0.0/24'
  vyos@vyos# set protocols igmp-proxy interface eth0 role 'upstream'
  vyos@vyos# set protocols igmp-proxy interface eth1 role 'downstream'

  vyos@vyos# show protocols
   igmp-proxy {
       disable-quickleave
       interface eth0 {
           alt-subnet 172.16.35.0/24
           alt-subnet 172.31.0.0/24
           role upstream
       }
       interface eth1 {
           role downstream
       }
   }

OP mode commands:
-----------------

  vyos@vyos:~$ show ip multicast interface
   Interface  BytesIn      PktsIn       BytesOut     PktsOut      Local
   eth0       0.0b         0            0.0b         0            xxx.xxx.xxx.65
   eth1       0.0b         0            0.0b         0            xxx.xxx.xx.201

  vyos@vyos:~$ show ip multicast mfc
  Group           Origin          Pkts         Bytes        Wrong   In      Out
  xxx.x.xx.1      xxx.xx.0.1      10           9.81KB       0       eth0    eth1
  xxx.x.xx.2      xxx.xx.0.1                                        --

1 files changed, 241 insertions, 0 deletions

diff --git a/src/op_mode/show-igmpproxy.py b/src/op_mode/show-igmpproxy.py
new file mode 100755
index 000000000..a021fcdde
--- /dev/null
+++ b/src/op_mode/show-igmpproxy.py
@@ -0,0 +1,241 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2018 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# File: show-igmpproxy
+# Purpose:
+#    Display istatistics from IPv4 IGMP proxy.
+#    Used by the "run show ip multicast" command tree.
+
+import sys
+import jinja2
+import argparse
+import ipaddress
+import socket
+
+import vyos.config
+
+# Output Template for "show ip multicast interface" command
+#
+# Example:
+# Interface  BytesIn      PktsIn       BytesOut     PktsOut      Local
+# eth0       0.0b         0            0.0b         0            xxx.xxx.xxx.65
+# eth1       0.0b         0            0.0b         0            xxx.xxx.xx.201
+# eth0.3     0.0b         0            0.0b         0            xxx.xxx.x.7
+# tun1       0.0b         0            0.0b         0            xxx.xxx.xxx.2
+vif_out_tmpl = """
+{%- for r in data %}
+{{ "%-10s"|format(r.interface) }} {{ "%-12s"|format(r.bytes_in) }} {{ "%-12s"|format(r.pkts_in) }} {{ "%-12s"|format(r.bytes_out) }} {{ "%-12s"|format(r.pkts_out) }} {{ "%-15s"|format(r.loc) }}
+{%- endfor %}
+"""
+
+# Output Template for "show ip multicast mfc" command
+#
+# Example:
+# Group             Origin            In    Out           Pkts        Bytes        Wrong
+# xxx.xxx.xxx.250   xxx.xx.xxx.75     --
+# xxx.xxx.xx.124    xx.xxx.xxx.26     --
+mfc_out_tmpl = """
+{%- for r in data %}
+{{ "%-15s"|format(r.group) }} {{ "%-15s"|format(r.origin) }} {{ "%-12s"|format(r.pkts) }} {{ "%-12s"|format(r.bytes) }} {{ "%-12s"|format(r.wrong) }} {{ "%-10s"|format(r.iif) }} {{ "%-20s"|format(r.oifs|join(', ')) }}
+{%- endfor %}
+"""
+
+parser = argparse.ArgumentParser()
+parser.add_argument("--interface", action="store_true", help="Interface Statistics")
+parser.add_argument("--mfc", action="store_true", help="Multicast Forwarding Cache")
+
+def byte_string(size):
+    # convert size to integer
+    size = int(size)
+
+    # One Terrabyte
+    s_TB = 1024 * 1024 * 1024 * 1024
+    # One Gigabyte
+    s_GB = 1024 * 1024 * 1024
+    # One Megabyte
+    s_MB = 1024 * 1024
+    # One Kilobyte
+    s_KB = 1024
+    # One Byte
+    s_B  = 1
+
+    if size > s_TB:
+        return str(round((size/s_TB), 2)) + 'TB'
+    elif size > s_GB:
+        return str(round((size/s_GB), 2)) + 'GB'
+    elif size > s_MB:
+        return str(round((size/s_MB), 2)) + 'MB'
+    elif size > s_KB:
+        return str(round((size/s_KB), 2)) + 'KB'
+    else:
+        return str(round((size/s_B), 2)) + 'b'
+
+    return None
+
+def kernel2ip(addr):
+    """
+    Convert any given addr from Linux Kernel to a proper, IPv4 address
+    using the correct host byte order.
+    """
+
+    # Convert from hex 'FE000A0A' to decimal '4261415434'
+    addr = int(addr, 16)
+    # Kernel ABI _always_ uses network byteorder
+    addr = socket.ntohl(addr)
+
+    return ipaddress.IPv4Address( addr )
+
+def do_mr_vif():
+    """
+    Read contents of file /proc/net/ip_mr_vif and print a more human
+    friendly version to the command line. IPv4 addresses present as
+    32bit integers in hex format are converted to IPv4 notation, too.
+    """
+
+    with open('/proc/net/ip_mr_vif', 'r') as f:
+        lines = len(f.readlines())
+        if lines < 2:
+            return None
+
+    result = {
+        'data': []
+    }
+
+    # Build up table format string
+    table_format = {
+        'interface': 'Interface',
+        'pkts_in'  : 'PktsIn',
+        'pkts_out' : 'PktsOut',
+        'bytes_in' : 'BytesIn',
+        'bytes_out': 'BytesOut',
+        'loc'      : 'Local'
+    }
+    result['data'].append(table_format)
+
+    # read and parse information from /proc filesystema
+    with open('/proc/net/ip_mr_vif', 'r') as f:
+        header_line = next(f)
+        for line in f:
+            data = {
+                'interface': line.split()[1],
+                'pkts_in'  : line.split()[3],
+                'pkts_out' : line.split()[5],
+
+                # convert raw byte number to something more human readable
+                # Note: could be replaced by Python3 hurry.filesize module
+                'bytes_in' : byte_string( line.split()[2] ),
+                'bytes_out': byte_string( line.split()[4] ),
+
+                # convert IP address from hex 'FE000A0A' to decimal '4261415434'
+                'loc'      : kernel2ip( line.split()[7] ),
+            }
+            result['data'].append(data)
+
+    return result
+
+def do_mr_mfc():
+    """
+    Read contents of file /proc/net/ip_mr_cache and print a more human
+    friendly version to the command line. IPv4 addresses present as
+    32bit integers in hex format are converted to IPv4 notation, too.
+    """
+
+    with open('/proc/net/ip_mr_cache', 'r') as f:
+        lines = len(f.readlines())
+        if lines < 2:
+            return None
+
+    # We need this to convert from interface index to a real interface name
+    # Thus we also skip the format identifier on list index 0
+    vif = do_mr_vif()['data'][1:]
+
+    result = {
+        'data': []
+    }
+
+    # Build up table format string
+    table_format = {
+        'group' : 'Group',
+        'origin': 'Origin',
+        'iif'   : 'In',
+        'oifs'  : ['Out'],
+        'pkts'  : 'Pkts',
+        'bytes' : 'Bytes',
+        'wrong' : 'Wrong'
+    }
+    result['data'].append(table_format)
+
+    # read and parse information from /proc filesystem
+    with open('/proc/net/ip_mr_cache', 'r') as f:
+        header_line = next(f)
+        for line in f:
+            data = {
+                # convert IP address from hex 'FE000A0A' to decimal '4261415434'
+                'group' : kernel2ip( line.split()[0] ),
+                'origin': kernel2ip( line.split()[1] ),
+
+                'iif'   : '--',
+                'pkts'  : '',
+                'bytes' : '',
+                'wrong' : '',
+                'oifs'  : []
+            }
+
+            iif = int( line.split()[2] )
+            if not ((iif == -1) or (iif == 65535)):
+                data['pkts']  = line.split()[3]
+                data['bytes'] = byte_string( line.split()[4] )
+                data['wrong'] = line.split()[5]
+
+                # convert index to real interface name
+                data['iif']  = vif[iif]['interface']
+
+                # convert each output interface index to a real interface name
+                for oif in line.split()[6:]:
+                    idx = int( oif.split(':')[0] )
+                    data['oifs'].append( vif[idx]['interface'] )
+
+            result['data'].append(data)
+
+    return result
+
+if __name__ == '__main__':
+    args = parser.parse_args()
+
+    # Do nothing if service is not configured
+    c = vyos.config.Config()
+    if not c.exists_effective('protocols igmp-proxy'):
+        print("IGMP proxy is not configured")
+        sys.exit(0)
+
+    if args.interface:
+        data = do_mr_vif()
+        if data:
+            tmpl = jinja2.Template(vif_out_tmpl)
+            print(tmpl.render(data))
+
+        sys.exit(0)
+    elif args.mfc:
+        data = do_mr_mfc()
+        if data:
+            tmpl = jinja2.Template(mfc_out_tmpl)
+            print(tmpl.render(data))
+
+        sys.exit(0)
+    else:
+        parser.print_help()
+        sys.exit(1)
+