This file is indexed.

/usr/sbin/hv_set_ifconfig is in linux-cloud-tools-common 3.13.0-40.69.

This file is owned by root:root, with mode 0o755.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
#! /usr/bin/env python

# 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"

'''Get quiet'''
sys.stdout = open(os.devnull, 'w')
sys.stderr = open(os.devnull, 'w')

try:
	if_file=open(if_filename,"r+")
except IOError as e:
	exit(e.errno)
else:
	if_file.close()


def kvp_dict(file):
	return dict(line.strip().split("=") for line in file)


#setting the hwaddress to something azure is not expecting is fatal networking 

if len(sys.argv) != 2 :
	exit(errno.EINVAL)

kvp=dict(line.strip().split("=") for line in fileinput.input())

if not "HWADDR" in kvp :
	exit(errno.EPROTO)

if not "DEVICE" in kvp :
	exit(1)

output=[]
basename=kvp["DEVICE"]

if "DHCP" in kvp and kvp["DHCP"]=="yes" :
	output += ["auto " + basename]
	output += ["iface " + basename  + " inet dhcp"]
	output += [""]
else:
	''' Matchup the interface specific lines '''

	'''DNS entries will go with the first interface
	and there can be a max of three'''
	autolist=[]
	dns=[]
	if "DNS1" in kvp :
		dns+=[kvp["DNS1"]]
		if "DNS2" in kvp :
			dns+=[kvp["DNS2"]]
			if "DNS3" in kvp :
				dns+=[kvp["DNS3"]]


	'''
	    No real max for the number of interface + aliases ... 
	    only required is the address (but mate everything up that comes in. '''

	'''ipv4 first'''

	v4names=[name for name in kvp.keys() if name.startswith("IPADDR")]
	v4names.sort()

	v6names=[name for name in kvp.keys() if name.startswith("IPV6ADDR")]
	v6names.sort()

	'''IPV6 requires a netmask'''
	'''If an ipv6 exists, you'll want to turn off /proc/sys/net/ipv6/conf/all/autoconf with
	up echo 0 > /proc/sys/net/ipv6/conf/all/autoconf'''

	'''Counter needs to increment as soon as any interface is set.'''


	if_count=0

	for v4 in v4names:
		ifname=basename
		suffix=""
		if if_count :
			ifname+=":" + str(if_count)
			suffix="_"+str(if_count)
		if not ifname in autolist:
			autolist += [ifname]
		output += [ "iface " + ifname + " inet static"]
		output += [ "\t" + "address " + kvp[v4]]
		if "NETMASK"+suffix in kvp.keys():
			output += ["\tnetmask " + kvp["NETMASK"+suffix]]
		if "GATEWAY"+suffix in kvp.keys():
			output += ["\tgateway " + kvp["GATEWAY"+suffix]]
		if not if_count :
			output += ["\tdns-nameservers " + ' '.join(dns)]
		output += [""]
		if_count+=1

	if6_count=0
	if6_used=0
	for v6 in v6names:
		ifname=basename
		suffix=""
		if if6_used :
			ifname+=":" + str(if6_used)
		if if6_count :
			suffix="_" + str(if6_count)
		if not ifname in autolist:
			autolist += [ifname]
		if "IPV6NETMASK"+suffix in kvp.keys():
			output += [ "iface " + ifname + " inet6 static"]
			output += [ "\taddress " + kvp[v6]]
			output += [ "\tnetmask " + kvp["IPV6NETMASK"+suffix]]
			if "IPV6_DEFAULTGW"+suffix in kvp.keys():
				output += [ "\tgateway " + kvp["IPV6_DEFAULTGW"+suffix] ]
			if not if_count :
				output += ["\tdns-nameservers " + ' '.join(dns)]
			output += [""]
			if_count += 1
			if6_used += 1
		if6_count += 1

	output = ["auto "+" ".join(autolist)] + output
output=["# The following stanza(s) added by hv_set_ifconfig"] + output
output+=["#End of hv_set_ifconfig stanzas"]
print "==================================="
print output
print "==================================="


''' Time to clean out the existing interface file'''

f=open(if_filename,"r")
flines=f.readlines()
f.close()
newfile=[]
pitchstanza=0
inastanza=0
stanza=[]
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()]
	else:
		if inastanza:
			if not pitchstanza:
				stanza+=[line.strip()]
		else:
			if not pitchstanza:
				newfile += [line.strip()]


for line in newfile:
	print line
for line in output:
	print line


fd, path = tempfile.mkstemp()
for line in newfile:
	os.write(fd,line)
	os.write(fd,"\n")
for line in output:
	os.write(fd,line)
	os.write(fd,"\n")
os.close(fd)

shutil.copy(path,if_filename)
os.chmod(if_filename,0644)
#print "TMPFILE is at: " + path
#print "Copied file is at: " + if_filename


try:
    retcode = subprocess.call("ifdown "+basename , shell=True)
    if retcode < 0:
        print >>sys.stderr, "Child was terminated by signal", -retcode
    else:
        print >>sys.stderr, "Child returned", retcode
except OSError as e:
    print >>sys.stderr, "Execution failed:", e

try:
    retcode = subprocess.call("ifup "+basename , shell=True)
    if retcode < 0:
        print >>sys.stderr, "Child was terminated by signal", -retcode
    else:
        print >>sys.stderr, "Child returned", retcode
except OSError as e:
    print >>sys.stderr, "Execution failed:", e