wpa_cli_mod.py

from __future__ import print_function
from __future__ import division
from past.utils import old_div
import logging
import time
import subprocess

logger = logging.getLogger("hydrosys4."+__name__)

def db2dbm(quality):
	"""
	Converts the Radio (Received) Signal Strength Indicator (in db) to a dBm
	value.  Please see http://stackoverflow.com/a/15798024/1013960
	"""
	dbm = int((old_div(quality, 2)) - 100)
	return min(max(dbm, -100), -50)

"""
target is to implement the following:

wpa_cli status

wpa_cli scan

wpa_cli scan_results

wpa_cli list_network 
"""


#SUPPLICANT_LOG_FILE = "wpa_supplicant.log"


def run_program(cmd):
	"""
	Runs a program, and it's paramters (e.g. rcmd="ls -lh /var/www")
	Returns output if successful, or None and logs error if not.
	"""

	try:
		#ifup_output = subprocess.check_output(cmd).decode('utf-8')
		result=subprocess.run(cmd, capture_output="True", text="True")
		ifup_output=result.stdout
		#print(ifup_output)
		return ifup_output
	except subprocess.CalledProcessError as e:
		print("Something wrong: ", e)
		return "FAIL"


def wpa_terminate(_iface):
	"""
	Terminates any running wpa_supplicant process, and then starts a new one.
	"""
	cmd=['wpa_cli' , 'terminate']
	run_program(cmd)
	time.sleep(1)


def get_networks_old(iface, retry=1):
	"""
	Grab a list of wireless networks within range, and return a list of dicts describing them.
	"""
	while retry > 0:
		output=run_program(['wpa_cli', '-i' + iface , 'scan'])
		time.sleep(3)		
		if ("OK" in output.upper()):
			networks=[]
			lines = run_program(['wpa_cli', '-i' + iface , 'scan_result']).split("\n")
			time.sleep(1.5)			
			if lines:
				for line in lines[1:-1]:
					#bssid / frequency / signal level / flags / ssid
					if line:
						linevect=line.split('\t')
						if len(linevect)>4:
							b, fr, s, f, ss = line.split('\t')[:5]
							# according to the SSID naming, it is possible to have spaces in the SSID
							# damn it
							# SSID = final part of the line string, as separators "\t" seems to work
							networks.append( {"bssid":b, "freq":fr, "sig":s, "ssid":ss, "flag":f} )												

				if networks:
					return networks
		retry-=1
		logger.debug("Couldn't retrieve networks, retrying")
		time.sleep(0.5)
	logger.warning("Failed to list networks")
	return []

def getbetweenquotes(text):      
	import re
	matches=re.findall(r'\"(.+?)\"',text)
	# matches is now ['String 1', 'String 2', 'String3']
	if matches:
		return matches[0]
	else:
		return ""

def get_networks(iface, retry=1):
	"""
	Grab a list of wireless networks within range
	"""
	cmd = ["sudo" , "iwlist", iface, "scan" ] #"scan | grep 'ESSID'"]  # sudo is necessary
	while retry > 0:
		output=run_program(cmd)		
		if output:
			networks=[]
			for line in output.split("\n"):
				#bssid / frequency / signal level / flags / ssid
				if line:
					if 'ESSID:' in line:
						essid=getbetweenquotes(line)
						networks.append( {"ssid":essid} )												

			if networks:
				return networks
		retry-=1
		logger.debug("Couldn't retrieve networks, retrying")
		time.sleep(0.5)
	logger.warning("Failed to list networks")
	return []


def remove_all(iface):
	"""
	Disconnect all wireless networks.
	"""
	cmd=['sudo','wpa_cli', '-i' + iface , 'list_networks']
	lines = run_program(cmd).split("\n")
	if lines:
		for line in lines[1:-1]:
			net_id=line.split()[0]
			remove_network(iface,net_id) 

def remove_network(iface,net_id):
	cmd=['sudo','wpa_cli', '-i' + iface , 'remove_network' , net_id]
	run_program(cmd)  

def get_saved_networks(iface):
	cmd=['sudo','wpa_cli', '-i' + iface , 'list_networks']
	lines = run_program(cmd).split("\n")
	networks=[]
	if lines:
		for line in lines[1:-1]:
			datavect = line.split("\t") # do not use space as separator, the SSID can have spaces inside
			if len(datavect)>1:
				# network id / ssid / bssid / flags
				networks.append( {"net_id":datavect[0], "ssid":datavect[1]} )
	return networks

def get_net_id(iface,ssid):
	# find net_id
	networks=get_saved_networks(iface)
	for item in networks:
		if item["ssid"]==ssid:
			net_id=item["net_id"]
			print("Network ID of the SSID = ",ssid, " ID= ", net_id)
			return net_id
	return ""



def remove_network_ssid(iface,ssid):
	# find net_id
	net_id=get_net_id(iface,ssid)
	if net_id:
		print("net id to remove ", net_id)
		remove_network(iface,net_id)
		print("saved ",  saveconfig(iface))
		updateconfig(iface)	
		return True
	return False



def disable_all(iface):
	"""
	Disable all wireless networks.
	"""
	cmd=['sudo','wpa_cli', '-i' + iface , 'list_networks']
	lines = run_program(cmd).split("\n")
	if lines:
		for line in lines[1:-1]:
			net_id=line.split()[0]
			disable_network(iface,net_id)
		return True
	return False

def disable_network_ssid(iface,ssid):
	if ssid=="":
		return disable_all(iface)
	else:
		# find net_id
		net_id=get_net_id(iface,ssid)
		if net_id:
			print("net id to disable ", net_id)
			return disable_network(iface,net_id)
	return False


def disable_network(iface,net_id):
	cmd=['sudo','wpa_cli', '-i' + iface , 'disable_network' , net_id]
	strout=run_program(cmd)
	if not "OK" in strout:
		return False
	return True

def enable_network(iface,net_id):
	cmd=['sudo','wpa_cli', '-i' + iface , 'enable_network' , net_id]
	run_program(cmd)

def updateconfig(iface):
	cmd=['sudo','wpa_cli', '-i' + iface ,'reconfigure']
	run_program(cmd)
	
def saveconfig(iface):	
	cmd=['sudo','wpa_cli', '-i' + iface ,'save_config' ]
	strout=run_program(cmd)
	if not "OK" in strout:
		return False
	return True
	
def save_network(iface,ssid,password):
	# if same SSID already present then remove it before saving
	remove_network_ssid(iface,ssid)
	cmd=['sudo','wpa_cli', '-i' + iface , 'add_network']
	net_id=run_program(cmd)
	print("Net ID to add " , net_id)
	cmd=['sudo','wpa_cli', '-i' + iface , 'set_network', net_id , 'ssid' , '"'+ssid+'"' ]
	strout=run_program(cmd)
	print("ssid set " , strout)
	if not "OK" in strout:
		return False
	cmd=['sudo','wpa_cli', '-i' + iface , 'set_network', net_id , 'psk' , '"'+password+'"' ]
	strout=run_program(cmd)
	print("ssid psk " , strout)
	if not "OK" in strout:
		return False

	# enable network
	#enable_network(iface,net_id)
	
	# save config	
	if not saveconfig(iface):
		return False
	
	updateconfig(iface)
	return True
	


def enable_ssid(iface, ssid):

	cmd=['sudo' , 'wpa_cli', '-i' + iface , 'list_networks']
	lines = run_program(cmd).split("\n")
	if lines:
		for line in lines[1:-1]:
			strlist = line.split("\t")  # do not use space as separator, the SSID can have spaces inside
			if strlist:
				net_id=strlist[0]			
				ssidout=strlist[1]
				if ssid==ssidout:					
					enable_network(iface,net_id)
					return True
	return False

def listsavednetwork(iface):
	#updateconfig(iface)
	cmd=['sudo','wpa_cli', '-i' + iface , 'list_networks']
	lines = run_program(cmd).split("\n")
	data=[]
	if lines:
		for line in lines[1:-1]:
			strlist = line.split("\t") # do not use space as separator, the SSID can have spaces inside
			if len(strlist)>1:
				net_id=strlist[0]			
				ssidout=strlist[1]
				if ssidout!="":
					data.append(ssidout)
	return data


def status(iface):
	"""
	Check if we're associated to a network.
	"""
	cmd=['sudo','wpa_cli', '-i' + iface , 'status']
	lines = run_program(cmd).split("\n")
	if lines:
		data=[]
		for line in lines[1:-1]:
			strlist = line.split("=")
			if len(strlist)>1:
				itemdict={}
				itemdict[strlist[0]]=strlist[1]
				data.append(itemdict)
	return data

def has_ip(_iface):
	"""
	Check if we have an IP address assigned
	"""
	status = run_program("wpa_cli -i %s status" % _iface)
	r = re.search("ip_address=(.*)", status)
	if r:
		return r.group(1)
	return False

def do_dhcp(_iface):
	"""
	Request a DHCP lease.
	"""
	run_program("dhclient %s" % _iface)



if __name__ == "__main__":
	network = get_networks("wlan0")
	print(network)