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# kpov_util should be imported by add_assignment.py
instructions = {
'si': '''\
<p>
Postavi dva navidezna računalnika: <em>SimpleArbiter</em> in <em>VPNClient1</em>. Poskrbite, da bosta povezana med seboj in v internet. Na <em>VPNClient1</em> namestite OpenVPN in program za nadzor nad virtualnimi napravami (s katerim kreirate napravo <code>tap</code>).
<p>
Na strežniku <em>SimpleArbiter</em> že teče strežnik in uporablja skrivnost, ki jo najdete tudi na <em>VPNClient1</em> v domačem imeniku uporabnika <code>student</code>. Na <em>VPNClient1</em> vzpostavite VPN tako, da napišete primerno datoteko z nastavitvami. Računalniku <em>VPNClient1</em> na navideznem lokalnem omrežju nastavite naslov
<code>{{IP_VPNClient1}}</code>.
<p>
Nato poskrbite, da bo na <em>VPNClient1</em> na navideznem omrežju prek NFS omogočen
dostop do imenika <code>/home/test/{{DIRNAME}}</code>. V ta imenik skopirajte datoteke, ki so prek SMB dostopne na <em>SimpleArbiter</em>.
''',
'en': '''\
<p>
Setup two virtual machines: <em>SimpleArbiter</em> and <em>VPNClient1</em>. Set the client's network up so that it has access to the internal network and the internet. On <em>VPNClient1</em>, install OpenVPN and a program for supervising virtual devices
(which you will use to create a <code>tap</code> device). On the VPN, set the IP for
<em>VPNClient1</em> to <code>{{IP_VPNClient1}}</code>.
<p>
An OpenVPN server is already running on <em>SimpleArbiter</em>. Use the secret
available on <em>VPNClient1</em> in the home directory of user <code>student</code> to connect to the VPN server on <em>SimpleArbiter</em>. To do that, you will have to write your
own OpenVPN configuration file.
<p>
After you have set up the VPN, make the directory <code>/home/test/{{DIRNAME}}</code> on <em>VPNClient1</em> available over NFS from <em>SimpleArbiter</em> over
your VPN. Copy files that are available from <em>SimpleArbiter</em> over SMB to <code>/home/test/{{DIRNAME}}</code>.
'''
}
computers = {
'SimpleArbiter': {
'disks': [
{
'name': 'simpleArbiterDhcpGWVPN',
},
],
'network_interfaces': [
{
'network': 'test-net'
},
{
'network': 'net1'
}
],
'flavor': 'm1.tiny',
'config_drive': False
},
'VPNClient1': {
'disks': [
{ 'name': 'student-VPNClient1',
},
],
'network_interfaces': [
{
'network': 'net1'
}
],
'flavor': 'm1.tiny',
'config_drive': False
},
}
networks = {
'test-net': {
'public': True
},
# Used for the VPN tunnel
'net1': {
'public': False
}
}
#Tukaj sem generiral tri parametre, prosil bi če se upoštevajo pri Tasku.
params_meta = {
'IP_SimpleArbiterVPN': {'descriptions':{'si':'IP za SimpleArbiter na VPN'}, 'w': False, 'public': True, 'type': 'IP', 'generated': True},
'IP_VPNClient1': {'descriptions':{'si':'IP klienta na VPN'}, 'w': False, 'public': True, 'type': 'IP', 'generated': True},
'IP_LANClient1': {'descriptions':{'si':'IP klienta na LAN'}, 'w': True, 'public': True, 'type': 'IP', 'generated': False},
'DIRNAME': {'descriptions':{'si':'Imenik, dostopen prek NFS'}, 'w': False, 'public': True, 'type': 'IP', 'generated': True},
'secret_random_seed': {'descriptions':{'si':'Seme za skrivnost'}, 'w': False, 'public': False, 'type': None, 'generated': True},
}
def task(IP_SimpleArbiterVPN, IP_VPNClient1, IP_LANClient1, DIRNAME):
import collections
from pexpect import pxssh # Used to set up an SSH connection to a remote machine
import pexpect # Allows the script to spawn a child application and control it as if a human were typing commands
# The necessary things we need to check if the task was performed correctly
results = collections.defaultdict(str)
# VPNClient1
sC1 = pxssh.pxssh(encoding='utf-8')
sC1.login(IP_LANClient1, 'student', 'vaje')
# sA
results['SimpleArbiter_ifconfig'] = pexpect.run(
'ifconfig -a', encoding='utf-8', env={'PATH': '/bin:/sbin'})
results['SimpleArbiter_route'] = pexpect.run(
'route -n', encoding='utf-8', env={'PATH': '/bin:/sbin'})
# Pings each of the clients
# 10.8.0.6 and 10.8.0.10 are the first two default addresses distributed by OpenVPN
# Will output everything ping outputs (set to ping 3 times)
results['SimpleArbiter_ping_C1'] = pexpect.run(
'ping -c 3 {}'.format(IP_VPNClient1), encoding='utf-8')
results['SimpleArbiter_traceroute'] = pexpect.run(
'traceroute {}'.format(IP_VPNClient1), encoding='utf-8')
sC1.sendline('cat /etc/exports')
sC1.prompt()
output = sC1.before
results['VPNClient1_nfs_access_control_list'] = output
results['SimpleArbiter_mount'] = pexpect.run(
'sudo mount {}:/home/test/{} /mnt'.format(IP_VPNClient1, DIRNAME), encoding='utf-8')
results['SimpleArbiter_mount_result'] = pexpect.run(
'sudo mount', encoding='utf-8')
results['SimpleArbiter_ls'] = pexpect.run(
'ls /mnt', encoding='utf-8')
pexpect.run(
'sudo umount /mnt', encoding='utf-8')
# Ping the VPN server
sC1.sendline('ping -c 3 {0}'.format( IP_SimpleArbiterVPN ))
sC1.prompt()
results['VPNClient1_ping_VPN_server'] = sC1.before
sC1.sendline('/sbin/ifconfig -a')
sC1.prompt()
results['VPNClient1_ifconfig'] = sC1.before
sC1.sendline('ps xa')
sC1.prompt()
results['VPNClient1_ps'] = sC1.before
sC1.logout()
return results
def gen_params(user_id, params_meta):
params = dict()
#Tukaj sem generiral te tri parametre (ime skupne skrivnosti je heidi )
#(ime imenika kjer naj bo shranjena skupna skrivnost naj bo openvpn)
#(HASH bo naključno generiran niz iz user_id s katerim se bo preverjalo plagiatorstvo)
import random
r = random.Random(user_id)
net = kpov_util.IPv4_subnet_gen(r, '10.168.0.0/16', 24)
params['IP_VPNClient1'], params['IP_SimpleArbiterVPN'] = kpov_util.IPv4_addr_gen(r, net, 2)
params['DIRNAME'] = kpov_util.fname_gen(r, extension=False)
params['secret_random_seed']=str(r.random())
return params
def task_check(results, params):
import re
score = 0
hints = []
IP_SA = params['IP_SimpleArbiterVPN'].replace('.', '\.')
IP_C1 = params['IP_VPNClient1'].replace('.', '\.')
rs = r"tap0: flags=.* mtu 1500\r\n +inet {}".format(IP_SA)
if re.search(rs,
results['SimpleArbiter_ifconfig']):
score += 1
else:
hints.append("ifconfig on SimpleArbiter not OK")
if re.search(
"PING.*\r\n64 bytes from {}: icmp_seq=[0-9]+ ttl=64 time=[0-9.]* ms".format(IP_C1),
results['SimpleArbiter_ping_C1']):
score += 1
else:
hints.append("ping from server not OK")
rs = "1 +{0} \({0}\)".format(IP_C1)
if re.search(rs, results['SimpleArbiter_traceroute']):
score += 1
else:
hints.append("traceroute not OK")
if results['VPNClient1_nfs_access_control_list'].find(
'/home/test/' + params['DIRNAME'] + ' ') >= 0:
score += 1
if results['SimpleArbiter_mount_result'].find(
'{}:/home/test/{} on /mnt type nfs'.format(
params['IP_VPNClient1'], params['DIRNAME'])):
score += 1
else:
hints.append("mount not OK")
# get r into the correct state
r = random.Random(params['secret_random_seed'])
s = "\n".join(["".join([r.choice("0123456789abcdef") for i in range(32)])
for i in range(16)])
keyfile = kpov_util.fname_gen(r, extension=False)
# now check the filenames
fnames_ok = True
for i in range(3):
fname = kpov_util.fname_gen(r, False)
foo = kpov_util.fortune(r, 4096)
pos = results['SimpleArbiter_ls'].find(fname + '.txt')
fnames_ok = fnames_ok and pos >= 0
if fnames_ok:
score += 2
else:
hints.append("shared filenames not OK:")
# Ping the VPN server
if re.search(
"PING.*\r\n64 bytes from {}: icmp_seq=[0-9]+ ttl=64 time=[0-9.]* ms".format(IP_SA),
results['VPNClient1_ping_VPN_server']):
score += 1
else:
hints.append("ping from client not OK")
rs = r"tap0: flags=.* mtu 1500\r\n +inet {}".format(IP_C1)
if re.search(rs, results['VPNClient1_ifconfig']):
score += 1
else:
hints.append("ifconfig on VPNClient1 not OK")
if results['VPNClient1_ps'].find('openvpn') > 0:
score += 1
else:
hints.append("openvpn not found running on VPNClient")
return score, hints
def prepare_disks(templates, task_params, global_params):
#guestmount -a d -m /dev/VG/LV -m /dev/sda1:/boot --ro /mnt
#asistent je pocasnela :)
import random
r = random.Random(task_params['secret_random_seed'])
s = "\n".join([
"".join([r.choice("0123456789abcdef") for i in range(32)])
for i in range(16)])
s = """#
# 2048 bit OpenVPN static key
#
-----BEGIN OpenVPN Static key V1-----
{}
-----END OpenVPN Static key V1-----
""".format(s)
keyfile = kpov_util.fname_gen(r, extension=False) + ".key"
templates['simpleArbiterDhcpGWVPN'].write("/etc/openvpn/secret.key", s)
netaddr_s = """auto tap0
iface tap0 inet static
openvpn server
pre-up tunctl -t tap0
address {}
netmask 255.255.255.0
""".format(task_params['IP_SimpleArbiterVPN'])
templates['simpleArbiterDhcpGWVPN'].write_append("/etc/network/interfaces", netaddr_s)
for i in range(3):
fname = kpov_util.fname_gen(r, False)
templates['simpleArbiterDhcpGWVPN'].write(
"/srv/smb/" + fname + '.txt',
kpov_util.fortune(r, 4096))
write_default_config(templates['simpleArbiterDhcpGWVPN'], global_params)
templates['student-VPNClient1'].write("/home/student/" + keyfile, s)
# uid, gid (student = )
templates['student-VPNClient1'].chown(1000, 1000, "/home/student/" + keyfile)
write_default_config(templates['simpleArbiterDhcpGWVPN'], global_params)
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