#!/usr/bin/python3
#
# hv_set_ifconfig <config> -- take the hv_kvp_daemon generated configuration
# file and apply it to the Ubuntu configuration.
#
# CONFIG example:
# HWADDR=11:22:33:44:55:66
# DEVICE=foo1
# DHCP=yes
# CONFIG example:
# HWADDR=11:22:33:44:55:66
# DEVICE=foo1
# IPADDR=192.168.99.10
# GATEWAY=192.168.99.1
# DNS1=192.168.88.250
# IPADDR2=192.168.99.11
# IPV6ADDR=2001:DB8:99::10
# IPV6NETMASK=64
# IPV6_DEFAULTGW=2001:DB8:99::10
# set interfaces in hv_kvp_daemon style
import fileinput
import sys
import errno
import os
import shutil
import tempfile
import subprocess
if_filename="/etc/network/interfaces"
# Drop our output (XXX?)
sys.stdout = open(os.devnull, 'w')
sys.stderr = open(os.devnull, 'w')
# Confirm we can open the network configuration.
try:
if_file=open(if_filename,"r+")
except IOError as e:
exit(e.errno)
else:
if_file.close()
# Usage: hv_set_ifconfig <config>
if len(sys.argv) != 2 :
exit(errno.EINVAL)
#
# Here is the format of the ip configuration file:
#
# HWADDR=macaddr
# DEVICE=interface name
# BOOTPROTO=<protocol> (where <protocol> is "dhcp" if DHCP is configured
# or "none" if no boot-time protocol should be used)
#
# IPADDR0=ipaddr1
# IPADDR1=ipaddr2
# IPADDRx=ipaddry (where y = x + 1)
#
# NETMASK0=netmask1
# NETMASKx=netmasky (where y = x + 1)
#
# GATEWAY=ipaddr1
# GATEWAYx=ipaddry (where y = x + 1)
#
# DNSx=ipaddrx (where first DNS address is tagged as DNS1 etc)
#
# IPV6 addresses will be tagged as IPV6ADDR, IPV6 gateway will be
# tagged as IPV6_DEFAULTGW and IPV6 NETMASK will be tagged as
# IPV6NETMASK.
#
kvp=dict(line.strip().split("=") for line in fileinput.input())
# Setting the hwaddress to something azure is not expecting is fatal
# to networking.
if not "HWADDR" in kvp :
exit(errno.EPROTO)
# Confirm we have a device specified.
if not "DEVICE" in kvp :
exit(1)
autolist = []
output=[]
basename=kvp["DEVICE"]
# DNS entries will go with the first interface and there can be a max
# of three. These will be emitted with the first interface.
dns = []
for count in (1, 2, 3):
key = "DNS" + str(count)
if key in kvp:
dns += [kvp[key]]
dns_emitted = False
# IPV4 may either be dhcp or static.
if ("DHCP" in kvp and kvp["DHCP"] == "yes") or \
("BOOTPROTO" in kvp and kvp["BOOTPROTO"] == "dhcp"):
autolist.append(basename)
output += ["iface " + basename + " inet dhcp"]
output += [""]
else:
# Matchup the interface specific lines
# No real max for the number of interface + aliases ...
# only required is the address (but mate everything up that comes in.
# IPv4 -- ensure we sort by numeric suffixes.
v4names = [ int(name[6:]) for name in kvp.keys() if name.startswith("IPADDR") ]
v4names.sort()
for if_count in v4names:
ifname = basename
which = str(if_count)
if if_count:
ifname += ":" + str(if_count)
which_gw = which
else:
which_gw = ""
if not ifname in autolist:
autolist += [ifname]
output += [ "iface " + ifname + " inet static" ]
output += [ "\t" + "address " + kvp["IPADDR" + which] ]
if "NETMASK" + which in kvp:
output += [ "\tnetmask " + kvp["NETMASK" + which] ]
if "GATEWAY" + which_gw in kvp:
output += ["\tgateway " + kvp["GATEWAY" + which_gw]]
if not dns_emitted:
dns_emitted = True
output += ["\tdns-nameservers " + ' '.join(dns)]
output += [""]
# IPv6 requires a netmask
# If an ipv6 exists, you'll want to turn off /proc/sys/net/ipv6/conf/all/autoconf with
# echo 0 > /proc/sys/net/ipv6/conf/all/autoconf
v6names = [ int(name[8:]) for name in kvp.keys() if name.startswith("IPV6ADDR") ]
v6names.sort()
for if6_count in v6names:
ifname = basename
which = str(if6_count)
if if6_count:
ifname += ":" + str(if6_count)
which_gw = which
else:
which_gw = ""
if not ifname in autolist:
autolist += [ifname]
if "IPV6NETMASK" + which in kvp:
output += [ "iface " + ifname + " inet6 static"]
output += [ "\taddress " + kvp["IPV6ADDR" + which]]
output += [ "\tnetmask " + kvp["IPV6NETMASK" + which]]
if "IPV6_DEFAULTGW" + which_gw in kvp:
output += [ "\tgateway " + kvp["IPV6_DEFAULTGW" + which_gw] ]
if not dns_emitted:
dns_emitted = True
output += ["\tdns-nameservers " + ' '.join(dns)]
output += [""]
# Mark this new interface for automatic up.
if len(autolist):
output = ["auto "+" ".join(autolist)] + output
print("===================================")
print(output)
print("===================================")
# Time to clean out the existing interface file
# Markers.
start_mark = "# The following stanza(s) added by hv_set_ifconfig"
end_mark = "#End of hv_set_ifconfig stanzas"
f=open(if_filename,"r")
flines=f.readlines()
f.close()
newfile=[]
pitchstanza=0
inastanza=0
stanza=[]
prev_line=None
for line in flines:
if line.startswith("auto"):
if inastanza:
if not pitchstanza:
newfile.extend(stanza)
stanza=[]
inastanza=0
newline=""
autoline=line.strip().split(" ")
for word in autoline:
if (not word == basename) and (not word.startswith(basename+":")):
newline+=word + " "
newline = newline.strip()
if not newline == "auto":
newfile += [newline.strip()]
elif line.startswith(("iface","mapping","source")):
'''Read a stanza'''
'''A Stanza can also start with allow- ie allow-hotplug'''
if inastanza:
if not pitchstanza:
newfile.extend(stanza)
stanza=[]
inastanza=1
pitchstanza=0
autoline=line.strip().split(" ")
for word in autoline:
if (word == basename) or (word.startswith(basename+":")):
pitchstanza=1
if not pitchstanza:
stanza+=[line.strip()]
elif line.strip() in (start_mark, end_mark):
if inastanza:
if not pitchstanza:
newfile.extend(stanza)
stanza=[]
inastanza = 0
pitchstanza = 0
# Deduplicate markers.
if line != prev_line:
newfile += [line.strip()]
else:
if inastanza:
if not pitchstanza:
stanza+=[line.strip()]
else:
if not pitchstanza:
newfile += [line.strip()]
prev_line=line
# Include pending stanza if any.
if inastanza and not pitchstanza:
newfile.extend(stanza)
def emit(line):
print(line)
output = line + "\n"
os.write(fd, output.encode('utf-8'))
# Insert the new output at the end and inside the existing markers if found.
emitted = False
fd, path = tempfile.mkstemp()
for line in newfile:
if line == end_mark:
emit("\n".join(output))
emitted = True
emit(line)
if not emitted:
emit(start_mark)
emit("\n".join(output))
emit(end_mark)
os.close(fd)
shutil.copy(path,if_filename)
os.chmod(if_filename,0o644)
#print("TMPFILE is at: " + path)
#print("Copied file is at: " + if_filename)
try:
retcode = subprocess.call("ifdown "+basename , shell=True)
if retcode < 0:
print("Child was terminated by signal", -retcode, file=sys.stderr)
else:
print("Child returned", retcode, file=sys.stderr)
except OSError as e:
print("Execution failed:", e, file=sys.stderr)
try:
retcode = subprocess.call("ifup "+basename , shell=True)
if retcode < 0:
print("Child was terminated by signal", -retcode, file=sys.stderr)
else:
print("Child returned", retcode, file=sys.stderr)
except OSError as e:
print("Execution failed:", e, file=sys.stderr)
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