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 autolist = []
  87 output=[]
  88 basename=kvp["DEVICE"]
  89
  90 # DNS entries will go with the first interface and there can be a max
  91 # of three.  These will be emitted with the first interface.
  92 dns = []
  93 for count in (1, 2, 3):
  94     key = "DNS" + str(count)
  95     if key in kvp:
  96         dns += [kvp[key]]
  97 dns_emitted = False
  98
  99 # IPV4 may either be dhcp or static.
 100 if ("DHCP" in kvp and kvp["DHCP"] == "yes") or \
 101    ("BOOTPROTO" in kvp and kvp["BOOTPROTO"] == "dhcp"):
 102     autolist.append(basename)
 103     output += ["iface " + basename  + " inet dhcp"]
 104     output += [""]
 105 else:
 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 if len(autolist):
 172     output = ["auto "+" ".join(autolist)] + output
 173
 174 print("===================================")
 175 print(output)
 176 print("===================================")
 177
 178
 179 # Time to clean out the existing interface file
 180
 181 # Markers.
 182 start_mark = "# The following stanza(s) added by hv_set_ifconfig"
 183 end_mark = "#End of hv_set_ifconfig stanzas"
 184
 185 f=open(if_filename,"r")
 186 flines=f.readlines()
 187 f.close()
 188 newfile=[]
 189 pitchstanza=0
 190 inastanza=0
 191 stanza=[]
 192 prev_line=None
 193 for line in flines:
 194     if line.startswith("auto"):
 195         if inastanza:
 196             if not pitchstanza:
 197                 newfile.extend(stanza)
 198             stanza=[]
 199         inastanza=0
 200         newline=""
 201         autoline=line.strip().split(" ")
 202         for word in autoline:
 203             if (not word == basename) and (not word.startswith(basename+":")):
 204                 newline+=word + " "
 205         newline = newline.strip()
 206         if not newline == "auto":
 207             newfile += [newline.strip()]
 208     elif line.startswith(("iface","mapping","source")):
 209         '''Read a stanza'''
 210         '''A Stanza can also start with allow- ie allow-hotplug'''
 211         if inastanza:
 212             if not pitchstanza:
 213                 newfile.extend(stanza)
 214             stanza=[]
 215         inastanza=1
 216         pitchstanza=0
 217         autoline=line.strip().split(" ")
 218         for word in autoline:
 219             if (word == basename) or (word.startswith(basename+":")):
 220                 pitchstanza=1
 221         if not pitchstanza:
 222             stanza+=[line.strip()]
 223     elif line.strip() in (start_mark, end_mark):
 224         if inastanza:
 225             if not pitchstanza:
 226                 newfile.extend(stanza)
 227             stanza=[]
 228         inastanza = 0
 229         pitchstanza = 0
 230         # Deduplicate markers.
 231         if line != prev_line:
 232             newfile += [line.strip()]
 233     else:
 234         if inastanza:
 235             if not pitchstanza:
 236                 stanza+=[line.strip()]
 237         else:
 238             if not pitchstanza:
 239                 newfile += [line.strip()]
 240     prev_line=line
 241
 242 # Include pending stanza if any.
 243 if inastanza and not pitchstanza:
 244     newfile.extend(stanza)
 245
 246
 247 def emit(line):
 248     print(line)
 249     output = line + "\n"
 250     os.write(fd, output.encode('utf-8'))
 251
 252 # Insert the new output at the end and inside the existing markers if found.
 253 emitted = False
 254 fd, path = tempfile.mkstemp()
 255 for line in newfile:
 256     if line == end_mark:
 257         emit("\n".join(output))
 258         emitted = True
 259     emit(line)
 260 if not emitted:
 261     emit(start_mark)
 262     emit("\n".join(output))
 263     emit(end_mark)
 264 os.close(fd)
 265
 266 shutil.copy(path,if_filename)
 267 os.chmod(if_filename,0o644)
 268
 269 #print("TMPFILE is at: " + path)
 270 #print("Copied file is at: " + if_filename)
 271
 272 try:
 273     retcode = subprocess.call("ifdown "+basename , shell=True)
 274     if retcode < 0:
 275         print("Child was terminated by signal", -retcode, file=sys.stderr)
 276     else:
 277         print("Child returned", retcode, file=sys.stderr)
 278 except OSError as e:
 279     print("Execution failed:", e, file=sys.stderr)
 280
 281 try:
 282     retcode = subprocess.call("ifup "+basename , shell=True)
 283     if retcode < 0:
 284         print("Child was terminated by signal", -retcode, file=sys.stderr)
 285     else:
 286         print("Child returned", retcode, file=sys.stderr)
 287 except OSError as e:
 288     print("Execution failed:", e, file=sys.stderr)