Thrown together script to do a rough analysis of ASA/LINA "show access-list" output to see how it is compiling and find ineffficient rules

parseasa.py

#!/bin/python
#

import re
import argparse

def example(filename):
    items = []
    # P3 with open(filename, newline='') as f:
    try:
        with open(filename, 'r') as f:
            reader = unicodeDictReader(f)
            for row in reader:
                try:
                    items.append(row)
                except:
                    print("Error reading following row in %s : %s" % (filename,row))
        return items
    except IOError:
        print("Error loading file %s. Will not continue. Please check file exists." % filename)
        print("Error:", sys.exc_info())
        sys.exit()
    except TypeError:
        print("Error loading file %s. Will not continue. Please check file is correctly formatted." % filename)
        print("Error:", sys.exc_info())
        sys.exit()


def loadlog(filename):
    items = []
    rules = {}
    try:
        with open(filename,'r') as infile:
            pass
    except:
        print("Can't open file with name: %s. Please specify the file to parse with (for example) parseasa.py --file youfilename.txt" % filename)
        return
    with open(filename,'r') as infile:
        for line in infile:
            if 'access-list' in line:
                splitline = line.split(' ')
                if splitline[2] == "line":
                    # print("Found real ACL, %d elements" % len(splitline))
                    # we are interested
                    if splitline[4] == "remark":
                        ruleId = splitline[6][:-1]
                        rules[ruleId] = { 
                            'ruleId': ruleId,
                            'count': 0,
                            'aggrhitcnt': 0,
                            'nohitElements': 0
                            } 
                        # Get the metadata
                        # pos 7 could be RULE, PREFILTER [POLICY], ACCESS [POLICY], L4 [RULE], L7 [RULE]
                        if splitline[7] == "RULE:":
                            rules[ruleId]['RULE'] = splitline[8:]
                        elif splitline[7] == "PREFILTER":
                            rules[ruleId]['PREFILTER_POLICY'] = splitline[9:]
                        elif splitline[7] == "ACCESS":
                            rules[ruleId]['ACCESS_POLICY'] = splitline[9:]
                        elif splitline[7] == "L4":
                            rules[ruleId]['L4_RULE'] = splitline[9:]
                        elif splitline[7] == "L7":
                            rules[ruleId]['L7_RULE'] = splitline[9:]
                        else:
                            print("Found a remark I don't understand")
                            print(splitline)
                    elif splitline[4] == "advanced":
                        if "object-group" in splitline:
                            # This must be the rule definition
                            pass
                    else:
                        # something unhandled
                        print("unhandled at 01")
                        print(splitline)
                elif splitline[0] == '' and splitline[1] =='':
                    # This must be a component
                    #
                    # print("component")
                    try:
                        indexId = splitline.index('rule-id')
                        ruleId = splitline[indexId+1]
                        rules[ruleId]['count'] += 1
                    except:
                        print("problem" )
                    # Get hitcount of element
                    try:
                        hitcount = splitline[-3:-2]
                        hitcount = int(re.findall(r'\d+', hitcount[0])[0])
                        #print(hitcount)
                        if hitcount == 0:
                            rules[ruleId]['nohitElements'] += 1
                        else:
                            rules[ruleId]['aggrhitcnt'] += hitcount

                    except:
                        print("Problem getting hitcount")
                else:
                    print(splitline)                  
    #print(rules)
    #print()
    # Make a sorting dict
    sdict = []
    total = 0
    for k,v in rules.items():
        sdict.append((k,v['count']))
        total = total + v['count']
    for s in sorted(sdict, key=lambda sdict: sdict[1]):
        percent = int(100 * s[1] / total)
        try:
            percentUnhit = int(100 * rules[s[0]]['nohitElements'] / s[1])
        except:
            percentUnhit = 0
        print("Rule " + s[0] + ", count " + repr(s[1]) + ", percent unused: " + repr(percentUnhit) + "%, percent of mem: " + repr(percent) + "%, info: " + repr(rules[s[0]]))



def main():
    parser = argparse.ArgumentParser(description='What filename should I parse?')
    parser.add_argument('--file', action="store", dest="filename", help='Name of file to parse')
    results = parser.parse_args()
    print("Hi. Loading file: %s" % results.filename)
    loadlog(results.filename)    


if __name__ == "__main__":
   main()