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@pletch
Last active September 24, 2023 13:16
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Scrape OpnSense DHCP Leases Status Page and Export Results as List
#!/usr/bin/env python3
#
# This python script provides a function to query the opnSense (v21.3 - v23.1.x) dhcp leases status page and
# return a list of tuples including ip, hostname, and mac address. This script will not work with version 23.7.x+
# due to changes in the DHCP lease page.
# See comment from dheldt on modified version that works using api searchLeases page.
# To use the original script, ensure LXML is installed via package manager or via pip.
#
# 27-Mar-2021 - Original release
# 17-Jul-2022 - Fix url in scrape function. Add error trapping for case where user/pass are not set up correctly.
# 24-Sep-2023 - Add note about 23.7.x incompatibility.
#
import sys
import requests
from lxml import html
import re
url = "http://192.168.1.1/status_dhcp_leases.php" #change url to match your opnSense machine address. Note http or https!
user = 'your_username' #Username for opnSense login (default is 'root')
password = 'your_password' #Password for opnSense login
def scrape_opnsense_dhcp(url, user, password):
ip = []
mac = []
hostname = []
s = requests.session()
r = s.get(url,verify = False)
matchme = '"X-CSRFToken", "(.*)" \);'
csrf = re.search(matchme,str(r.text))
payload = {
'login' : 'Login',
'usernamefld' : user,
'passwordfld' : password
}
r = s.post(url,data=payload,verify = False,headers={"X-CSRFToken":csrf.group(1)})
r = s.get(url,verify = False)
tree = html.fromstring(r.content)
tr_elements = tree.xpath('//tr')
try:
headers = [header.text for header in tr_elements[0]]
except IndexError:
print("Error retrieving lease list. Are you sure username and password were set up in script?")
quit()
ip.extend(tree.xpath('//table[@class="table table-striped"]//tbody//tr//td[' + str(headers.index('IP address') + 1) +']//text()'))
for node in tree.xpath('//table[@class="table table-striped"]//tbody//tr//td['+ str(headers.index('MAC address') + 1) +']'):
if bool(re.search(r'([0-9a-f]{2}(?::[0-9a-f]{2}){5})', node.text)):
mac.append(node.text)
for node in tree.xpath('//table[@class="table table-striped"]//tbody//tr//td['+ str(headers.index('Hostname') + 1) +']'):
if node.text is None:
hostname.append('no_hostname')
else:
hostname.append(node.text)
for i in range(len(mac)):
mac[i] = mac[i].strip()
return(list(zip(ip, mac, hostname)))
if __name__ == "__main__":
dhcp_list = scrape_opnsense_dhcp(url, user, password)
for entry in dhcp_list:
print(entry)
@kellerassel007
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kellerassel007 commented Jun 13, 2023

I updated the code to work with latest OPNSense version 23.1.9. It seems that it required an additional field in POST request.
Also I included the description of each device from DHCP overview.

Usage:
OPNSENSE_USERNAME=root OPNSENSE_PASSWORD='abc' python3 opnsense-dhcp-ip-overview.py

#!/usr/bin/env python3

#
# # This python script provides a function to query the opnSense (+v21.3) dhcp leases status page and return a list of tuples including 
# ip, hostname, and mac address. To use, ensure LXML is installed via package manager or via pip.
#
# 27-Mar-2021 - Original release
# 17-Jul-2022 - Fix url in scrape function. Add error trapping for case where user/pass are not set up correctly.
# 13-Jun-2023 - Fix missing field in POST request for new OPNSense version. Added field Description.
#

# Use:
# OPNSENSE_USERNAME=marcel OPNSENSE_PASSWORD='abc' python3 opnsense-dhcp-ip-overview.py

import os
import sys
import requests
import urllib3
import re
from lxml import html

urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)

url  = "https://192.168.1.1/status_dhcp_leases.php" #change url to match your opnSense machine address. Note http or https!
user = os.getenv('OPNSENSE_USERNAME')
password = os.getenv('OPNSENSE_PASSWORD')

def scrape_opnsense_dhcp(url, user, password):
   ip = []
   mac = []
   hostname = []
   description = []

   s = requests.session()
   r = s.get(url,verify = False)

   matchme = '"X-CSRFToken", "(.*)" \);'
   csrf = re.search(matchme,str(r.text))
   csrf_token = csrf.group(1)
   
   matchme = 'input type="hidden" name="([^"]*)" value="([^"]*)"'
   hidden_field = re.search(matchme,str(r.text))
   hidden_field_id = hidden_field.group(1)
   hidden_field_value = hidden_field.group(2)

   payload = {
'login' : '1',
'usernamefld' : user,
'passwordfld' : password
}

   payload[hidden_field_id] = hidden_field_value

   r = s.post(url,data=payload,verify = False,headers={"X-CSRFToken":csrf_token})
   r = s.get(url,verify = False)
   tree = html.fromstring(r.content)
   tr_elements = tree.xpath('//tr')
   try:
      headers = [header.text for header in tr_elements[0]]
   except IndexError:
      print("Error retrieving lease list. Are you sure username and password were set up in script?")
      quit()

   ip.extend(tree.xpath('//table[@class="table table-striped"]//tbody//tr//td[' + str(headers.index('IP address') + 1) +']//text()'))

   for node in tree.xpath('//table[@class="table table-striped"]//tbody//tr//td['+ str(headers.index('MAC address') + 1) +']'):
      if bool(re.search(r'([0-9a-f]{2}(?::[0-9a-f]{2}){5})', node.text)):
         mac.append(node.text)

   for node in tree.xpath('//table[@class="table table-striped"]//tbody//tr//td['+ str(headers.index('Hostname') + 1) +']'):
      if node.text is None:
         hostname.append('no_hostname')
      else:
         hostname.append(node.text)
         
   for node in tree.xpath('//table[@class="table table-striped"]//tbody//tr//td['+ str(headers.index('Description') + 1) +']'):
      if node.text is None:
         description.append('no_description')
      else:
         description.append(node.text)

   for i in range(len(mac)):
      mac[i] = mac[i].strip()

   return(list(zip(ip, mac, hostname, description)))

if __name__ == "__main__":     
    dhcp_list = scrape_opnsense_dhcp(url, user, password)

    for entry in dhcp_list:
            print(entry)

@dheldt
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dheldt commented Sep 19, 2023

Hi there,

for me, neither version works (having an OPNsense 23.7.3-amd64 running).
First of all because on my system there is no status_dhcp_leases.php present. Instead I get a "Page not found"-Error.

But I stumplet across /api/dhcpv4/leases/searchlease, which does work on my system. A simple get Request there (in a browser where I am logged in) gives a json object of the form:

{"total":18,"rowCount":18,"current":1,"rows":[{"address":"192.168.x.y","type":"static","mac":"SomeMac","starts":"","ends":"","hostname":"firstHost","descr":"","if_descr":"default","if":"opt8","state":"active","status":"offline","man":"manufacturer"},
....

]

so ... maybe this is the right way to go and fix instead of parsing html?

And, thank you a lot for your work and script, which has led me to the get-endpoint in the first place!

@pletch
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Author

pletch commented Sep 19, 2023

Yes, this is broken as of 23.7.x due to changes in the lease page. I haven't dug into trying to fix yet.

I wasn't aware of the searchlease endpoint but it does indeed seem like an opportunity to simplify. Will take a look when I get a little time in the next few days.

@dheldt
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dheldt commented Sep 19, 2023

If you adept as follows, it does (currently) work:

mainUrl = "https://192.168.1.1/"
url  = "https://192.168.1.1/api/dhcpv4/leases/searchlease

   s = requests.session()
   r = s.get(mainUrl,verify = False)

   if not(r == 200):
   	print("failed to connect")

   matchme = '"X-CSRFToken", "(.*)" \);'
   csrf = re.search(matchme,str(r.text))
   csrf_token = csrf.group(1)
   
   matchme = 'input type="hidden" name="([^"]*)" value="([^"]*)"'
   hidden_field = re.search(matchme,str(r.text))
   hidden_field_id = hidden_field.group(1)
   hidden_field_value = hidden_field.group(2)

   payload = {
'login' : '1',
'usernamefld' : user,
'passwordfld' : password
}

   payload[hidden_field_id] = hidden_field_value
   r = s.post(mainUrl,data=payload,verify = False,headers={"X-CSRFToken":csrf_token})
  
   if not(r == 200):
   	print("failed to log in")
   	
   r = s.get(url,verify = False)
   
   return r.json()

Note that you need to use two different urls now, because the log in does not work for the rest endpoint.

regards,

daniel

@pletch
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Author

pletch commented Sep 19, 2023

Thank you for working through this!

It turns out it is simpler to set up an api access key as described here:
https://docs.opnsense.org/development/how-tos/api.html.

The code to retrieve the leases can then simply be reduced to a single GET request.

import json
import requests

# define endpoint and credentials
api_key = '---------'   #use your unique key
api_secret = '-----------------'  #use your unique secret
url = 'http://opnsense.home/api/dhcpv4/leases/searchlease'
r = requests.get(url,
                 verify='OPNsense.pem',
                 auth=(api_key, api_secret))

if r.status_code == 200:
    return r.json()
else:
    print ('Connection / Authentication issue, response received:')

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