11h00 - TP « Encapsulation du parseur DHCP »

dhcpd.conf

 1: #
 2: # DHCP Server Configuration file.
 3: #   see /usr/share/doc/dhcp*/dhcpd.conf.sample
 4: #
 5: ddns-update-style ad-hoc;
 6: not authoritative;
 7: min-lease-time 43200;
 8: max-lease-time 43200;
 9:
10: subnet 172.19.45.0 netmask 255.255.255.0 {
11:         deny unknown-clients ;
12:         range 172.19.45.245 172.19.45.254;
13:         option subnet-mask              255.255.0.0;
14:         option domain-name-servers      172.19.45.18,172.19.45.20;
15:         option routers  172.19.0.254;
16: }
17:
18: host coquil-gw1 { hardware ethernet 00:1d:09:0a:33:db; fixed-address coquil-gw1; }
19: host fpl { hardware ethernet 00:26:b9:5d:32:32; fixed-address fpl; }
20: host roundcube
21: {
22:   hardware ethernet 00:16:36:09:2d:b9; fixed-address roundcube;
23: }
24: host deux { hardware ethernet 00:14:38:63:6E:F3; fixed-address deux; }
25: host visiteur1 { hardware ethernet 00:00:aa:be:93:5d; }
26: host visiteur2 { hardware ethernet 00:60:B0:D5:3B:05; }

main.py

 1: #!/usr/bin/python
 2:
 3: import DHCP.Database as database
 4:
 5: db = database.Database()
 6:
 7: db.addPattern( "mac", 'hardware\s+ethernet\s+(\S+)' )
 8: db.addPattern( "ip",  'fixed-address\s+(\S+)'       )
 9: db.load('dhcpd.conf')
10: db.dump()

DHCP/__init__.py

1: # un fichier vide pour que python sache qu'il s'agit d'un module

DHCP/Host.py

 1: #!/usr/bin/python
 2:
 3: class Host:
 4:     def __init__(self,hostname,attributes):
 5:         self.hostname=hostname
 6:         self.attributes=attributes
 7:
 8:     def __repr__(self):
 9:         return 'DHCP::Host(hostname="%s",attributes=%s)'%(self.hostname,self.attributes)

DHCP/Database.py

 1: #!/usr/bin/python
 2: import pprint
 3: import re
 4: import Host
 5: class Database:
 6:     def __init__(self):
 7:         self.pattern={}
 8:         self.hosts=[]
 9:     def addPattern(self,key,pattern):
10:         self.pattern[key]=pattern
11:     def dump(self):
12:         pprint.pprint(self.hosts)
13:     def load(self,filename):
14:         lines=''
15:         fh=open(filename)
16:         for line in fh.readlines():
17:             lines = lines + re.sub('#.*','',line.rstrip())
18:             hosts = re.findall('host\s[^}]*}',lines)
19:         for host in hosts:
20:             attributes={}
21:             m=re.match('host\s+(\S+)\s*{\s*(.*?)\s*}',host)
22:             if m:
23:                 hostname,context=m.group(1),m.group(2)
24:                 for field in re.split(';\s*',context):
25:                     for key,pattern in self.pattern.iteritems():
26:                         m=re.search(pattern,field)
27:                         if m:
28:                             attributes[key] = m.group(1)
29:                 self.hosts.append(Host.Host(hostname,attributes))

stdout

1: [user@tp-anf2012 python]$ python main.py
2: [DHCP::Host(hostname="coquil-gw1",attributes={'ip': 'coquil-gw1', 'mac': '00:1d:09:0a:33:db'}),
3:  DHCP::Host(hostname="fpl",attributes={'ip': 'fpl', 'mac': '00:26:b9:5d:32:32'}),
4:  DHCP::Host(hostname="roundcube",attributes={'ip': 'roundcube', 'mac': '00:16:36:09:2d:b9'}),
5:  DHCP::Host(hostname="deux",attributes={'ip': 'deux', 'mac': '00:14:38:63:6E:F3'}),
6:  DHCP::Host(hostname="visiteur1",attributes={'mac': '00:00:aa:be:93:5d'}),
7:  DHCP::Host(hostname="visiteur2",attributes={'mac': '00:60:B0:D5:3B:05'})]