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# SPDX-License-Identifier: AGPL-3.0-or-later
# TODO: dokoncaj!
# kpov_util should be imported by add_assignment.py
instructions = {
'si': '''\
<p>
Postavi štiri navidezne računalnike: <em>simpleArbiter</em>, <em>DHCP_server</em>, <em>BootableClientA</em> in <em>BootableClientB</em>.
<p>
Na <em>DHCP_server</em> postavi strežnik DHCP s pomočjo ISC dhcp 3 na naslovu <code>{{IP_DHCP}}</code>. <em>SimpleArbiter</em> naj dobi <code>{{IP_GW}}</code>. <em>DHCP_server</em> naj ga uporabi kot privzeti prehod (angl. <em lang="en">gateway</em>).
<p>
Če se zaganja <em>BootableClientB</em>, naj se sistem zažene v datoteko z imenom <code>{{BOOT_FNAME}}</code>. Če se zaganja katerikoli drug, naj se sistem zažene z živega USB, ki ga predstavlja slika diska <code>bootable_usb</code>, ime datoteke z zagonskim nalagalnikom pa naj bo kakršno koli razen <code>{{BOOT_FNAME}}</code>.
<p>
Živi USB priklopite na na <em>DHCP_server</em> in z njega poberite datoteke, potrebne za zagon. Datoteke z nastavitvami za PXELinux, ki jih najdete na živem USB, <em>morajo</em> biti dostopne na korenskem imeniku strežnika TFTP.
<p>
Tako <em>BootableClientA</em> kot <em>BootableClientB</em> naj bosta brez diskov.
''',
'en': '''\
<p>
Set up four virtual machines: <em>simpleArbiter</em>, <em>DHCP_server</em>, <em>BootableClientA</em> and <em>BootableClientB</em>.
<p>
On <em>DHCP_server</em>, set up a DHCP server using ISC dhcp 3. Set the IP address of this server to <code>{{IP_DHCP}}</code>. If <em>SimpleArbiter</em> requests an IP, have the DHCP server serve it <code>{{IP_GW}}</code>. <em>DHCP_server</em> should use <em>SimpleArbiter</em> as the gateway.
<p>
If <em>BootableClientB</em> tries to boot over the network, have the DHCP server tell it to boot from the file <code>{{BOOT_FNAME}}</code>. If any other system tries to boot over the network, have it boot from a live USB drive represented by the disk image <code>bootable_usb</code> and have the bootloader filename be different from <code>{{BOOT_FNAME}}</code>.
<p>
Connect the live USB to DHCP_server and copy the files neccessarry for it to boot. The PXELinux configuration files must be the same as the ones found on the live USB and <em>must</em> be accessible on the TFTP server root.
<p>
Both <em>BootableCLientA</em> and <em>BootableClientB</em> should be diskless.
''',
}
computers = {
'DHCPServer': {
'disks': [
{ 'name': 'student-DHCPServer',
},
{ 'name': 'bootable_usb',
'options':{'readonly': False},
'parts': [ {'dev': 'sdb1', 'path':'/mnt'} ],
},
],
'network_interfaces': [{'network': 'net1'}],
'flavor': 'm1.tiny',
'config_drive': False
},
'BootableClientA': {
'disks': [
],
'network_interfaces': [{'network': 'net1'}],
'flavor': 'm1.tiny',
'config_drive': False
},
'BootableClientB': {
'disks': [
],
'network_interfaces': [{'network': 'net1'}],
'flavor': 'm1.tiny',
'config_drive': False
},
'SimpleArbiter': {
'disks': [
{ 'name': 'simpleArbiterGW',
},
],
'network_interfaces': [{'network': 'net1'}, {'network': 'test-net'}],
'flavor': 'm1.tiny',
'config_drive': False
}
}
networks = { 'net1': {'public': False}, 'test-net': {'public': True} }
params_meta = {
'IP_DHCP': {'descriptions': {'si': 'IP DHCP streznika'}, 'w': False, 'public': True, 'type':'IP', 'generated': True},
'IP_GW': {'descriptions': {'si': 'IP SimpleArbiterja'}, 'w': False, 'public': True, 'type':'IP', 'generated': True},
'MAC_BOOT': {'descriptions': {'si': 'MAC racunalnika, ki se zazene z ISO'}, 'w': True, 'public': True, 'type':'MAC', 'generated': False},
# 'IP_BOOT': {'descriptions': {'si': 'IP racunalnika, ki se zazene z ISO'}, 'w': True, 'public': True, 'type':'IP', 'generated': False},
'TFTP_STRING': {'descriptions': {'si': 'vsebina'}, 'w': False, 'public': False, 'type':'short', 'generated': True},
'BOOT_FNAME': {'descriptions': {'si': 'Ime datoteke'}, 'w': False, 'public': True, 'type': 'filename', 'generated': True},
}
def task(IP_DHCP, IP_GW, MAC_BOOT, BOOT_FNAME):
# check the IP
# TODO (polz): Do not use tabs instead of spaces!
import pexpect
import re
import io
import time
results={}
# TODO (polz): Please use pexpect instead of os.system, it's much nicer.
# Also, test your functions. This function was obviously never run.
#
# check whether the fname served by the dhcp server is
# correct
# you should check the DHCP response from the server.
# You can use dhcpdump to get some packets, dhcping to create a
# DHCP Request. You may also use any other tool.
# If you choose to use dhcping, do not forget to set the hw address
# and ip arguments. You can simply feed it MAC_BOOT and IP_BOOT.
# dhcping -h MAC_BOOT -c IP_BOOT -V -r
# could work (but you should test it)
ip_str = pexpect.run('ip addr show', encoding='utf-8')
eth_re_str = r"ether (([0-9a-f]{{2}}:){{5}}[0-9a-f]{{2}})(.*)\r\n(.*){}(.*)\s(\w*)\r\n"
ip_re = re.search(eth_re_str.format(IP_GW), ip_str)
mac_SA = ip_re.group(1)
eth_dev_SA = ip_re.group(6)
dhcpdump = pexpect.spawn("sudo dhcpdump -i {}".format(eth_dev_SA), encoding='utf-8')
time.sleep(2)
results['dhcping_other'] = pexpect.run(
'sudo dhcping -s {} -h {} -c {}'.format(IP_DHCP, MAC_BOOT, IP_GW),
encoding='utf-8')
dhcpdump.expect('---------------------------------------------------------------------------')
results['dhcpdump_other_req'] = dhcpdump.before
dhcpdump.expect('---------------------------------------------------------------------------')
results['dhcpdump_other_reply'] = dhcpdump.before
dhcpdump.expect('---------------------------------------------------------------------------')
results['dhcpdump_other_release'] = dhcpdump.before
results['dhcping_SA'] = pexpect.run(
'sudo dhcping -s {} -h {} -c {}'.format(IP_DHCP, mac_SA, IP_GW),
encoding='utf-8')
dhcpdump.expect('---------------------------------------------------------------------------')
results['dhcpdump_SA_req'] = dhcpdump.before
dhcpdump.expect('---------------------------------------------------------------------------')
results['dhcpdump_SA_reply'] = dhcpdump.before
dhcpdump.expect('---------------------------------------------------------------------------')
results['dhcpdump_SA_release'] = dhcpdump.before
dhcpdump.sendintr()
tftp_client = pexpect.spawn('tftp {}'.format(IP_DHCP), encoding='utf-8')
tftp_client.expect(r'tftp>')
tftp_client.sendline('get pxelinux.cfg/default /dev/stdout')
tftp_client.expect(r'tftp>')
results['tftp_string'] = tftp_client.before
# check whether the fname served by the dhcp server is correct
# connect to the service in the special ISO
# check the MAC of the server on IP_BOOT
return results
def gen_params(user_id, params_meta):
params = dict()
r = random.Random(user_id)
net = kpov_util.IPv4_subnet_gen(r, '10.64.0.0/10', 24)
params['IP_DHCP'], params['IP_GW'] = kpov_util.IPv4_addr_gen(r, net, 2)
params['BOOT_FNAME'] = kpov_util.fname_gen(r)
params['TFTP_STRING'] = kpov_util.alnum_gen(r, 45)
return params
def task_check(results, params):
import re
score = 0
hints = []
#TO FINISH SCORING WE REQUIRE DICT KEYS AND FUNCTIONS gen_params AND task TO BE FINISHED
#POINTS FOR EACH TASK MAY BE ADJUSTED IN THE FUTURE
if results['dhcping_other'].find(params['IP_DHCP']) >= 0:
score += 1
else:
hints += ["DHCP wrong"]
if results['dhcping_SA'].find(params['IP_DHCP']) >= 0:
score += 1
else:
hints += ["DHCP wrong"]
p = re.search(r"FNAME:(.*)\.\r",
results['dhcpdump_other_reply'])
if p is not None:
other_fname = p.group(1).strip()
else:
other_fname = ''
if other_fname == params['BOOT_FNAME']:
score += 3
else:
hints += ["special fname wrong:" + other_fname]
p = re.search(r"FNAME:(.*)\.\r",
results['dhcpdump_SA_reply'])
if p is not None:
sa_fname = p.group(1).strip()
else:
sa_fname = ''
if sa_fname != params['BOOT_FNAME']:
score += 3
else:
hints += ["fname wrong:" + sa_fname]
try:
special_tftp = "# " + params['TFTP_STRING']
tftp_end = results['tftp_string'].split('\r\r\n')[-1]
assert tftp_end[:len(special_tftp)] == special_tftp
score += 2
except:
hints += ["tftp wrong"]
return score, hints
def prepare_disks(templates, task_params, global_params):
d = templates['student-DHCPServer']
s = """# {}""".format(task_params['TFTP_STRING'])
d = templates['bootable_usb']
d.write_append('/mnt/syslinux.cfg', s)
d = templates['simpleArbiterGW']
s = """auto lo
iface lo inet loopback
auto ens3
iface ens3 inet dhcp
auto enp0s3
iface enp0s3 inet dhcp
auto ens4
iface ens4 inet static
address {IP_GW}
netmask 255.192.0.0
auto enp0s8
iface enp0s8 inet static
address {IP_GW}
netmask 255.192.0.0
""".format(IP_GW = task_params['IP_GW'])
d.write("/etc/network/interfaces", s)
write_default_config(templates['simpleArbiterGW'], global_params)
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