debian/cloud-tools/hv_set_ifconfig

   1 #!/usr/bin/python3
   2 #
   3 # hv_set_ifconfig <config> -- take the hv_kvp_daemon generated configuration
   4 #                             file and apply it to the Ubuntu configuration.
   5 #
   6
   7 # CONFIG example:
   8 # HWADDR=11:22:33:44:55:66
   9 # DEVICE=foo1
  10 # DHCP=yes
  11
  12 # CONFIG example:
  13 # HWADDR=11:22:33:44:55:66
  14 # DEVICE=foo1
  15 # IPADDR=192.168.99.10
  16 # GATEWAY=192.168.99.1
  17 # DNS1=192.168.88.250
  18 # IPADDR2=192.168.99.11
  19 # IPV6ADDR=2001:DB8:99::10
  20 # IPV6NETMASK=64
  21 # IPV6_DEFAULTGW=2001:DB8:99::10
  22
  23 # set interfaces in hv_kvp_daemon style
  24 import fileinput
  25 import sys
  26 import errno
  27 import os
  28 import shutil
  29 import tempfile
  30 import subprocess
  31
  32 if_filename="/etc/network/interfaces"
  33
  34 # Drop our output (XXX?)
  35 sys.stdout = open(os.devnull, 'w')
  36 sys.stderr = open(os.devnull, 'w')
  37
  38 # Confirm we can open the network configuration.
  39 try:
  40     if_file=open(if_filename,"r+")
  41 except IOError as e:
  42     exit(e.errno)
  43 else:
  44     if_file.close()
  45
  46 # Usage: hv_set_ifconfig <config>
  47 if len(sys.argv) != 2 :
  48     exit(errno.EINVAL)
  49
  50 #
  51 # Here is the format of the ip configuration file:
  52 #
  53 # HWADDR=macaddr
  54 # DEVICE=interface name
  55 # BOOTPROTO=<protocol> (where <protocol> is "dhcp" if DHCP is configured
  56 #                       or "none" if no boot-time protocol should be used)
  57 #
  58 # IPADDR0=ipaddr1
  59 # IPADDR1=ipaddr2
  60 # IPADDRx=ipaddry (where y = x + 1)
  61 #
  62 # NETMASK0=netmask1
  63 # NETMASKx=netmasky (where y = x + 1)
  64 #
  65 # GATEWAY=ipaddr1
  66 # GATEWAYx=ipaddry (where y = x + 1)
  67 #
  68 # DNSx=ipaddrx (where first DNS address is tagged as DNS1 etc)
  69 #
  70 # IPV6 addresses will be tagged as IPV6ADDR, IPV6 gateway will be
  71 # tagged as IPV6_DEFAULTGW and IPV6 NETMASK will be tagged as
  72 # IPV6NETMASK.
  73 #
  74
  75 kvp=dict(line.strip().split("=") for line in fileinput.input())
  76
  77 # Setting the hwaddress to something azure is not expecting is fatal
  78 # to networking.
  79 if not "HWADDR" in kvp :
  80     exit(errno.EPROTO)
  81
  82 # Confirm we have a device specified.
  83 if not "DEVICE" in kvp :
  84     exit(1)
  85
  86 output=[]
  87 basename=kvp["DEVICE"]
  88
  89 # DNS entries will go with the first interface and there can be a max
  90 # of three.  These will be emitted with the first interface.
  91 dns = []
  92 for count in (1, 2, 3):
  93     key = "DNS" + str(count)
  94     if key in kvp:
  95         dns += [kvp[key]]
  96 dns_emitted = False
  97
  98 # IPV4 may either be dhcp or static.
  99 if ("DHCP" in kvp and kvp["DHCP"] == "yes") or \
 100    ("BOOTPROTO" in kvp and kvp["BOOTPROTO"] == "dhcp"):
 101     output += ["auto " + basename]
 102     output += ["iface " + basename  + " inet dhcp"]
 103     output += [""]
 104 else:
 105     autolist = []
 106     # Matchup the interface specific lines
 107
 108     # No real max for the number of interface + aliases ...
 109     # only required is the address (but mate everything up that comes in.
 110
 111     # IPv4 -- ensure we sort by numeric suffixes.
 112     v4names = [ int(name[6:]) for name in kvp.keys() if name.startswith("IPADDR") ]
 113     v4names.sort()
 114
 115     for if_count in v4names:
 116         ifname = basename
 117         which = str(if_count)
 118
 119         if if_count:
 120             ifname += ":" + str(if_count)
 121             which_gw = which
 122         else:
 123             which_gw = ""
 124
 125         if not ifname in autolist:
 126             autolist += [ifname]
 127
 128         output += [ "iface " + ifname + " inet static" ]
 129         output += [ "\t" + "address " + kvp["IPADDR" + which] ]
 130         if "NETMASK" + which in kvp:
 131             output += [ "\tnetmask " + kvp["NETMASK" + which] ]
 132         if "GATEWAY" + which_gw in kvp:
 133             output += ["\tgateway " + kvp["GATEWAY" + which_gw]]
 134
 135         if not dns_emitted:
 136             dns_emitted = True
 137             output += ["\tdns-nameservers " + ' '.join(dns)]
 138         output += [""]
 139
 140 # IPv6 requires a netmask
 141 # If an ipv6 exists, you'll want to turn off /proc/sys/net/ipv6/conf/all/autoconf with
 142 # echo 0 > /proc/sys/net/ipv6/conf/all/autoconf
 143 v6names = [ int(name[8:]) for name in kvp.keys() if name.startswith("IPV6ADDR") ]
 144 v6names.sort()
 145
 146 for if6_count in v6names:
 147     ifname = basename
 148     which = str(if6_count)
 149
 150     if if6_count:
 151         ifname += ":" + str(if6_count)
 152         which_gw = which
 153     else:
 154         which_gw = ""
 155
 156     if not ifname in autolist:
 157         autolist += [ifname]
 158
 159     if "IPV6NETMASK" + which in kvp:
 160         output += [ "iface " + ifname + " inet6 static"]
 161         output += [ "\taddress " + kvp["IPV6ADDR" + which]]
 162         output += [ "\tnetmask " + kvp["IPV6NETMASK" + which]]
 163         if "IPV6_DEFAULTGW" + which_gw in kvp:
 164             output += [ "\tgateway " + kvp["IPV6_DEFAULTGW" + which_gw] ]
 165         if not dns_emitted:
 166             dns_emitted = True
 167             output += ["\tdns-nameservers " + ' '.join(dns)]
 168         output += [""]
 169
 170 # Mark this new interface for automatic up.
 171 output = ["auto "+" ".join(autolist)] + output
 172
 173 print("===================================")
 174 print(output)
 175 print("===================================")
 176
 177
 178 # Time to clean out the existing interface file
 179
 180 # Markers.
 181 start_mark = "# The following stanza(s) added by hv_set_ifconfig"
 182 end_mark = "#End of hv_set_ifconfig stanzas"
 183
 184 f=open(if_filename,"r")
 185 flines=f.readlines()
 186 f.close()
 187 newfile=[]
 188 pitchstanza=0
 189 inastanza=0
 190 stanza=[]
 191 prev_line=None
 192 for line in flines:
 193     if line.startswith("auto"):
 194         if inastanza:
 195             if not pitchstanza:
 196                 newfile.extend(stanza)
 197             stanza=[]
 198         inastanza=0
 199         newline=""
 200         autoline=line.strip().split(" ")
 201         for word in autoline:
 202             if (not word == basename) and (not word.startswith(basename+":")):
 203                 newline+=word + " "
 204         newline = newline.strip()
 205         if not newline == "auto":
 206             newfile += [newline.strip()]
 207     elif line.startswith(("iface","mapping","source")):
 208         '''Read a stanza'''
 209         '''A Stanza can also start with allow- ie allow-hotplug'''
 210         if inastanza:
 211             if not pitchstanza:
 212                 newfile.extend(stanza)
 213             stanza=[]
 214         inastanza=1
 215         pitchstanza=0
 216         autoline=line.strip().split(" ")
 217         for word in autoline:
 218             if (word == basename) or (word.startswith(basename+":")):
 219                 pitchstanza=1
 220         if not pitchstanza:
 221             stanza+=[line.strip()]
 222     elif line.strip() in (start_mark, end_mark):
 223         if inastanza:
 224             if not pitchstanza:
 225                 newfile.extend(stanza)
 226             stanza=[]
 227         inastanza = 0
 228         pitchstanza = 0
 229         # Deduplicate markers.
 230         if line != prev_line:
 231             newfile += [line.strip()]
 232     else:
 233         if inastanza:
 234             if not pitchstanza:
 235                 stanza+=[line.strip()]
 236         else:
 237             if not pitchstanza:
 238                 newfile += [line.strip()]
 239     prev_line=line
 240
 241
 242
 243 def emit(line):
 244     print(line)
 245     output = line + "\n"
 246     os.write(fd, output.encode('utf-8'))
 247
 248 # Insert the new output at the end and inside the existing markers if found.
 249 emitted = False
 250 fd, path = tempfile.mkstemp()
 251 for line in newfile:
 252     if line == end_mark:
 253         emit("\n".join(output))
 254         emitted = True
 255     emit(line)
 256 if not emitted:
 257     emit(start_mark)
 258     emit("\n".join(output))
 259     emit(end_mark)
 260 os.close(fd)
 261
 262 shutil.copy(path,if_filename)
 263 os.chmod(if_filename,0o644)
 264
 265 #print("TMPFILE is at: " + path)
 266 #print("Copied file is at: " + if_filename)
 267
 268 try:
 269     retcode = subprocess.call("ifdown "+basename , shell=True)
 270     if retcode < 0:
 271         print("Child was terminated by signal", -retcode, file=sys.stderr)
 272     else:
 273         print("Child returned", retcode, file=sys.stderr)
 274 except OSError as e:
 275     print("Execution failed:", e, file=sys.stderr)
 276
 277 try:
 278     retcode = subprocess.call("ifup "+basename , shell=True)
 279     if retcode < 0:
 280         print("Child was terminated by signal", -retcode, file=sys.stderr)
 281     else:
 282         print("Child returned", retcode, file=sys.stderr)
 283 except OSError as e:
 284     print("Execution failed:", e, file=sys.stderr)